An x-ray zone plate was fabricated using the novel approach of focused ion beam (FIB) milling. The FIB technique was developed in recent years, it has been successfully used for transmission electron microscopy (TEM) sample preparation, lithographic mask repair, and failure analysis of semiconductor devices. During FIB milling, material is removed by the physical sputtering action of ion bombardment. The sputter yield is high enough to remove a substantial amount of material, therefore FIB can perform a direct patterning with submicron accuracy. The authors succeeded in fabricating an x-ray phase zone plate using the Micrion 9500HT FIB station, which has a 50 kV Ga{sup +} column. Circular Fresnel zones were milled in a 1.0-{micro}m-thick TaSiN film deposited on a silicon wafer. The outermost zone width of the zone plate is 170 nm at a radius of 60 {micro}m. An ...
Contents: expansion of pc mill application to platemill and tandem cold mill; application of cluster type rolling mill (cr mill) for rolling of special steel (illustration); development of on-line roll grinding system with profile meter; development of new type jet pickling; new technology in continuous annealing furnace (illustration); anti-seismic testing system by 3-dimensional shaking table; development of mitsubishi hybrid desulfurization system; field performance of 500 mw advanced coal fired supercritical pressure operation boiler for unit no. 1 of tsuruga thermal power station, hokuriku electric power co., inc.; development of electronically controlled cylinder liner lubrication system for marine diesel engines; prediction technology on steady-state and transient performance of multi-air conditioners; a knowledge-based system approach to the autonomous ...
Recent Kawasaki Steel's development on size and shape measurement techniques for hot steel rolling processes is reviewed. First, a precision enhancement technique for a laser distance meter is described, then its rugged structure necessary for measurement in such tough environment as hot rolling processes is described in detail. A plate length meters and an inter-stand sensors for a hot strip mill are shown as developed size measurement techniques. Furthermore, plate shape meters and laser profile gauges for H-beams are depicted as specific examples of shape measurement techniques. (author)
This paper describes high speed rolling and gauge control in cold tandem mill for ultra-thin gauge strip at the Chiba Works of Kawasaki Steel Corporation. To improve the plate-out property of rolling oil, cationic polymeric coagulant was prepared. Rolling oil with cohesion independent of inorganic inclusions or phosphatide was developed, to improve the lubrication for cold rolling, remarkably. In addition, a low-cost Ti-enhanced work roll having high wear resistance and excellent grindability was developed. Rolling can be conducted at the optimal rolling roughness and operation can be performed at the highest rolling speed independent of the rolling treatment amount. Rolling speed at 2800 m/min was confirmed by developing the rolling oil with excellent lubrication and the work roll having high wear resistance. For the improvement of strip thickness accuracy at the steady state rolling, use of the backup roll as roller bearing was more effective ...
The eastern oyster (Crassostrea virginica) developed neoplastic disorders when experimentally exposed both in the laboratory and field to chemically contaminated sediment from Black Rock Harbor (BRH),...Full Text Available
as manufacturing plants and laboratories, including the Chemical Laboratory at the House of David in Benton Harbor, Michigan. Built in America: Historic Building Buildings Survey/...
... Harbor Township Vineland Voorhees Pediatric Partner Hospitals AtlantiCare Regional Medical Center- City Campus, Atlantic City AtlantiCare Regional Medical Center - ...
... modules 2 and 3, 45 ft from each end) in a ... The toe of the stone revetment was 2 ft out from the ... in parentheses are for the current meters in layout 2. ...
Beach rocks are observed frequently on the tropical and subtropical sandy beaches where they express thin beds dipping seaward at less than 15 degrees. They consist of beach sediments including fossil shells, fragments of corals, diatoms and other biocarbonates, and are well cemented within the inter-tidal zone with calcium carbonate originated in sea water. Therefore, they are not only good indicators which show the past sea level, but also provide good sample material for radiocarbon dating. The locations of beach rocks give us an optimum condition studying a carbon cycle between land and marine environment by analyzing their isotope fractionations. In order to estimate the origin of calcium carbonate which worked as an adhesive when beach rocks were formed and to estimate the formative ages of beach rocks, a total of 330 fossil corals, fossil shells and calcarenite or calcirdite samples were collected from 128 sites of 16 islands consisting of the Nansei Islands, southwest of Japan. ...
Progress is reported on: radon barrier systems for uranium mill tailings; liner evaluation for uranium mill tailings; revegetation/rock cover for stabilization of inactive U-tailings sites; and application of long-term chemical biobarriers for uranium tailings.
Nanoindentation was performed on a Mo-alloy single crystal to investigate effects of focused ion beam (FIB) milling on mechanical behavior. On a non-FIB-milled surface, pop-ins were observed on all load-displacement curves corresponding to a transition from elastic to plastic deformation. Similar pop-ins were not detected on surfaces subjected to FIB milling. This difference indicates that FIB milling introduces damage that obviates the need for dislocation nucleation during subsequent deformation. A second effect of FIB milling is that it increased the surface hardness. Together, these effects could be the source of the size effects reported in the literature on micropillar tests.
The fungal pathogen Candida albicans is one of the leading causative agents of death in immunocompromised individuals. It harbors an arsenal of cell wall anchored factors that are implicated...Full Text Available
A single large plasmid was isolated from multiplasmid-harboring strains Rhizobium leguminosarum 1001 and R. trifolii 5. These single plasmids, as well as the largest plasmid detectable in R. phaseoli...Full Text Available
Mice harboring a null mutation in Abca4/Abcr serve as a model of autosomal recessive Stargardt disease. Consistent with the human retinal disorder, deficiency...Full Text Available
Hepatocellular carcinoma (HCC) is one of the most critical global health issues. With frequent association of viral liver disease, HCC is highly complex, harboring both cancer and chronic liver disease....Full Text Available
A strong necessary condition is given for the principal stabiliser of the action of a compact Lie group to have a non-zero centre. An application to the monopole problem in Yang-Mills-Higgs models is discussed.
The Yang-Mills equations are formulated in the form of generalized Maurer-Cartan equations, such that the corresponding algebraic operations are shown to satisfy the defining relations of homotopy Lie superalgebra.
The long term goal is to determine the ecological importance of specific toxic metals (copper and zinc) in harbors, through an understanding of their chemistry and biological effects at the base of marine food chains. This work provides information on potential problems with Zn and Cu, which may help to foresee problems in the future. Anthropogenic inputs of both metals are increasing; they are derived from diverse sources and are a simple function of population growth in coastal regions.
This Reference Book contains a current copy of the Clean Water Act (Section 404) and the Rivers and Harbors Act (Sections 9 and 10) and those regulations that implement those sections of the statutes and appear to be most relevant to DOE activities. The document is provided to DOE and contractor staff for informational purposes only and should not be interpreted as legal guidance. Updates that include important new requirements will be provided periodically. Questions concerning this Reference Book may be directed to Mark Petts, IH-231 (FTS 896-2609 or Commercial 202/586-2609).
This Reference Book contains a current copy of the Clean Water Act (Section 404) and the Rivers and Harbors Act (Sections 9 and 10) and those regulations that implement those sections of the statutes and appear to be most relevant to DOE activities. The document is provided to DOE and contractor staff for informational purposes only and should not be interpreted as legal guidance. Updates that include important new requirements will be provided periodically. Questions concerning this Reference Book may be directed to Mark Petts, IH-231 (FTS 896-2609 or Commercial 202/586-2609).
This work is focused on effect of various cooling strategies on surface roughness and tool wear during computer aided milling of soft workpiece materials. These milling operations were selected as dry milling, cool air cooling milling and fluid cooling milling. A cool air cooling system was designed and produced to cool end milling tools. Cool air was produced by a vortex tube. Annealed AISI 1050 was used as the workpiece material and cutting tool material was selected as HSS-Co8 DIN 844/BN. Optimal cutting parameters were selected according to workpiece hardness from reference catalog and kept for all tests. Tool wear and surface quality were measured for three different cooling types changing from ten minute machining time to thirty minute machining time. As a result, the surface roughne...
Medium-density polyethylene/multiwall carbon nanotube (MDPE/MWCNT) nanocomposites were produced by a mechanical milling method using a high-energy ball mill. The MDPE and MWCNTs were added to the ball mill at a constant 20:1 weight ratio of ball/powders and milled for 10 h to obtain polyethylene matrix nanocomposites reinforced with 0.5, 1, 2.5, and 5 weight percent of MWCNTs. To clarify the role of both MWCNT content and milling time on the morphology of MDPE, some nanocomposite samples were investigated by using a scanning electron microscope. To evaluate the role of milling on the microstructure of the nanocomposites, very thin films of MDPE/MWCNTs were prepared and studied by transmission electron microscopy. Thermal behavior of these nanocomposites was investigated by using differenti...
An experimental investigation was conducted to determine the feasibility of machining isogrid structures with abrasive-waterjets (AWJs). The main objective was to mill isogrid patterns in surfaces with accurate depth control using an AWJ. Three different approaches using AWJs were tested: linear cutting of isogrid patterns for diffusion bonding, milling with conventional AWJ nozzles, and milling with a single-angled rotary AWJ nozzle. It was shown that pocket milling with conventional AWJs is the most feasible of those tested. The milling can be done internally on preformed aluminum tubes, and the AWJ can also be used on materials other than aluminum. Accurate depth control can be achieved at high productivity rates. As an example, it is projected that a 48-inch-diameter skirt 12 inches high could be milled with an isogrid pattern in 6.3 hours. ...
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.
Fine-grained BaTiO3-based X7R ceramic materials were prepared and the effects of milling process on the core-shell structures and dielectric properties were investigated using scanning electron microscope, transmission electron microscope, and energy dispersive spectroscopy (EDS). As the milling time extends, the dielectric constant of the ceramics increases, whereas the temperature coefficient of capacitance at 125degreeC drops quickly. The changes in dielectric properties are considered relevant to the microstructure evolution caused by the milling process. Defects on the surface of BaTiO3 particles increase because of the effects of milling process, which will make it easier for additives to diffuse into the interior grains. As the milling time increases, the shell region gets thicker a...
Nineteen fungal strains having an ability to oxidize elemental sulfur in mineral salts medium were isolated from deteriorated sandstones of Angkor monuments. These fungi formed clearing zone on agar medium supplemented with powder sulfur due to the dissolution of sulfur. Representative of the isolates, strain THIF01, was identified as Fusarium solani on the basis of morphological characteristics and phylogenetic analyses. PCR amplification targeting 16S rRNA gene and analyses of full 16S rRNA gene sequence indicated strain THIF01 harbors an endobacterium Bradyrhizobium sp.; however, involvement of the bacterium in the sulfur oxidation is still unclear. Strain THIF01 oxidized elemental sulfur to thiosulfate and then sulfate. Germination of the spores of strain THIF01 was observed in a liqui...
This report presents geologic considerations that are pertinent to the Remedial Action Plan for Slick Rock mill tailings. Topics covered include regional geology, site geology, geologic stability, and geologic suitability.
The authors derive in full details the Hamiltonian formulation of the N = 1D = 10 supergravity coupled to super Yang-Mills theory. In particular, they present the explicit form of the first class constraints and compute the constraints gauge algebra.
Together with an investigation on the deformation behavior of hot and cold rolled strip edge, the edge-drop control was explained in characteristics and result of application to the commercial mill by the tapered-crown work roll (WR) shifting mill. From a cold rolling experiment, three-dimensional material flow was known to be generated in the vicinity of edge also at the time of rolling the strip, and which generation influences that of edge-drop. Almost linearly relative to the flattened deformation of WR, the edge-drop enlarges with enlargement in that deformation. The number of stands to be applied to the tapered-crown WR shifting mill in the tandem cold mill is determined by the location as far as which the strip is to be controlled in edge-drop. In case of improving it to obtain the edge-drop-free strip, all the stands are required to be equipped with tapered-crown WR shifting ...
Bacillus thuringiensis was isolated from 36 of 50 residue samples obtained from an animal feed mill (a stored-product environment). Of 710 selected colonies having Bacillus...Full Text Available
NaCl doped MgCl_2.nEtOH adducts were prepared by ball-milling MgCl_2.2.5EtOH with NaCl. Both the ball-milled MgCl_2.nEtOH/NaCl mixture and pure MgCl_2.2.5EtOH adducts were analyzed by X-ray diffraction (XRD), transmission electron microscope (TEM), thermogravimetry (TG) and differencial scanning calorimetry (DSC). A simple MgCl_2.nEtOH/NaCl mixture without ball-milling treatment was also studied for comparison. Two kinds of mixed crystals, Na_2MgCl_4 and NaMgCl_3, were found to be formed in a ball-milled mixture that contained 16 mol.% NaCl. TG and DSC analysis of the samples also provided indirect evidences supporting the presence of the mixed crystals in the ball-milled mixture. Adding certain amounts of NaCl in MgCl_2.2.5EtOH adduct, either by co-milling or by simple mixing, greatly increased the thermal stability of the adduct, but thermal decomposition ...
A comparative study has been carried out of the growth of two lines of Datura innoxia (Mill.) cells, designated DI-6 and NR1, their resistance to chlorate, and their ability to assimilate...Full Text Available
Noncommutative tori are among historically the oldest and by now the most developed examples of noncommutative spaces. Noncommutative Yang-Mills theory can be obtained from string theory. This connection led to a cross-fertilization of research in physics and mathematics on Yang-Mills theory on noncommutative tori. One important result stemming from that work is the link between T-duality in string theory and Morita equivalence of associative algebras. In this article we give an overview of the basic results in differential geometry of noncommutative tori. Yang-Mills theory on noncommutative tori, the duality induced by Morita equivalence and its link with the T-duality are discussed. Noncommutative Nahm transform for instantons is introduced.
The use of nickel alloys in Flue Gas Desulfurization (FGD) applications is described. Recently, nickel alloys 625 and C-276 have been clad to carbon steel plate. Production and properties of the clad plate are reviewed and a brief discussion is presented on production, fabrication and welding. Laboratory and field corrosion tests in SO/sub 2/ scrubber environments suggest that alloy 625 and C-276 clad steel plates are as corrosion resistant as the solid alloy plate.
This paper reviews the mill flowsheet applied at the SOMAIR (Societe des Mines de l'Air) uranium mill in Niger. It focuses on the yellow cake quality improvements achieved by molybdenum and zirconium elimination through double yellow cake precipitation in tanks at first stage and through size/density control in a fluidized bed precipitator at second stage. Water saving aspects in the plant are also presented. (author)
This paper reviews the mill flowsheet applied at the COMINAK uranium mill (Compagnie Miniere d'Akouta) in Niger. For ore treatment, it focuses on the major improvements to the operations using sulfonitric pugging and solids/liquid separation using belt filter double filtration after leaching. The precipitation circuits have been improved with molybdenum elimination through caustic washing of the yellow cake. (author)
A 269-kilobase conjugative plasmid, pK29, from a Klebsiella pneumoniae strain was sequenced. The plasmid harbors multiple antimicrobial resistance genes, including those encoding CMY-8...Full Text Available
The Bacillus anthracis Sterne plasmid pXO1 was sequenced by random, “shotgun” cloning. A circular sequence of 181,654 bp was generated. One hundred forty-three open...Full Text Available
The effects of sodium ions on the uptake of Hg2+ and induction of the Tn21 mer operon were studied by using Escherichia coli HMS174 harboring the reporter plasmids pRB28 and pOS14. Plasmid pRB28 carries...Full Text Available
...Resort and Convention Center, National Harbor, Maryland, USA September 18-20, 2011 XX HELSINKI DRUG RESEARCH CONGRESS Helsinki, Finland October 23-27, 2011 2011 AAPS Annual Meeting and Exposition Washington Convention Center Washington, DC June 26-29 2012 10th International Symposium on Pharmaceutical Sciences Ankara, Turkey Printer-friendly version Home | Elsevier ...
Staphylococcal cassette chromosome mec (SCCmec) is a mobile genetic element characterized by flanking terminal direct and, in most cases, inverted repeat sequences,...Full Text Available
HEW is operating one of the biggest district heating networks of the Federal Republic of Germany. The paper discusses a number of projects which in recent years have been engaged in extensive air pollution abatement measures to make district heating an environmentally compatible energy source. Emphasis is placed on the hot gas cleanup system of block 2 of the harbor power plant. The system is the first of its kind to have realized an SCR system connected with the desulfurization system for industrial denitrification purposes.
Richmond Harbor is on the eastern shoreline of central San Francisco Bay and its access channels and several of the shipping berths are no longer wide or deep enough to accommodate modem deeper-draft vessels. The Water Resources Development Act of 1986 (PL99-662) authorized the US Army Corps of Engineers (USACE), San Francisco District to deepen and widen the navigation channels in Richmond Harbor. Several options for disposal of the material from this dredging project are under consideration by USACE: disposal within San Francisco Bay, at open-ocean disposal sites, or at uplands disposal sites. Purpose of this study was to conduct comprehensive evaluations, including chemical, biological, and bioaccumulation testing of sediments in selected areas of Richmond Harbor. This information was required by the Environmental Protection Agency (EPA) and USACE. Battelle/Marine Sciences Laboratory collected 20 core samples, both 4-in. ...
The eastern oyster (Crassostrea virginica) developed neoplastic disorders when experimentally exposed both in the laboratory and field to chemically contaminated sediment from Black Rock Harbor (BRH), Bridgeport, Connecticut. Neoplasia was observed in oysters after 30 or 60 days of continuous exposure in a laboratory flow-through system to a 20 mg/L suspension of BRH sediment plus postexposure periods of 3, 30, or 60 days. Composite tumor incidence was 13.6% for both exposures. Tumor occurrence was highest in the renal excretory epithelium, followed in order by gill, gonad, gastrointestinal, heart, and embryonic neural tissue. Regression of experimental neoplasia was not observed when the stimulus was discontinued. In field experiments, gill neoplasms developed in oysters, deployed in cages for 30 days at BRH and 36 days at a BRH dredge material disposal area in Central Long Island Sound, and kidney and gastrointestinal neoplasms developed in caged oysters deployed ...
Four Escherichia coli isolates harboring CTX-M-14, with a single Ala231→Val substitution compared to CTX-M-9, had three different ribotypes. Cefotaxime resistance was plasmid...Full Text Available
In this work, wet ball milling method is used in order to improve hydrogen sorption behaviour due to its improved microstructure of solid hydrogen materials. Compared to traditional ball milling method, wet ball milling has benefits on improvement of MgH{sub 2} microstructure and further influences on its hydrogen sorption behavior. With the help of solvent tetrahydrofuran (THF), wet ball milled MgH{sub 2} powder has much smaller particle size and its specific surface area is 7 times as large as that of dry ball milled MgH{sub 2} powder. Although after ball milling the grain size is decreased a lot compared to as-received MgH{sub 2} powder, the grain size of wet ball milled MgH{sub 2} powder is larger than that of dry ball milled MgH{sub 2} powder due to the lubricant effect of solvent THF during wet ball ...
was to mount Pd-Ag terminated MLCCs onto gold plated mounting pads of a ... to protect against incorrect shipment of pure tin-plated MLCCs when Pd-Ag ...
20 nm thick permalloy elements, with dimensions of 500 x 500 nm"2 and 1000 x 200 nm"2, have been fabricated on 50 nm thick silicon nitride substrate by milling using a focussed ion beam (FIB) microscope. The dose of ion beam used for the milling was varied in order to achieve the best definition for the milled areas. The FIB milled elements were characterised physically by atomic force microscopy (AFM) and bright field transmission electron microscopy (TEM) and magnetically by Fresnel imaging on a TEM modified for magnetic imaging. The FIB milled elements were found to have a more irregular edge and lower magnetic fields for events such as vortex annihilation when compared to elements of the same dimensions fabricated by conventional electron beam microscopy (EBL).
An analytical study of the ice-formation process associated with heat-conducting plates located perpendicularly to isothermally heated and cooled surfaces with some clearance is presented. It is proposed that the onset conditions, which describe whether the ice-volume fraction in a steady state is greater than or less than that without heat-conducting plates, are defined by the dimensionless distances between the heated/cooled walls and the heat-conducting plates. It is shown that the onset conditions are dependent on the pitch and the thickness of the heat-conducting plates and are less dependent on the thermal conductivity of the plates.
Nanocrystalline Fe75Si20M5 (M = Al, B and Cr) powders were synthesized by mechanical alloying in a planetary ball mill from high purity elemental powders. Evolution of non-equilibrium solid solutions of ?-Fe[Si,(Al, B, Cr)] with a nanocrystalline structure was accompanied by the introduction of a large number of dislocation defects in the course of the milling process. Fe sites get substituted by Si and M (M = Al, B, Cr) atoms during the milling process. The structural change and the resulting disorder are reflected in the changes in the lattice parameter and average magnetic moment of the powders milled for various time periods. The effective magnetic anisotropy increases linearly with the milling time. An increase in coercivity with increasing milling time was observed which could be attributed to the introduction of dislocations and the reduction in the ...
MmMg{sub 12}-Ni amorphous or nanocrystalline composites (Mm: Ce-rich mischmetal) were prepared through the ball-milling method, and their electrochemical hydrogen storage performance was investigated and compared with that of ball-milled CeMg{sub 12}-Ni composites. It was found that the ball-milled MmMg{sub 12}-Ni composites had larger initial discharge capacities and better high rate dischargeability. Analysis of electrochemical impedance spectra (EIS) shows that the reaction resistance and hydrogen diffusion resistance of the ball-milled MmMg{sub 12}-Ni composites are lower as a result of the decrease in Ce content, and thus can contribute to the larger discharge capacity and better high rate dischargeability. Additionally, the cycle performance of the ball-milled MmMg{sub 12}-Ni composites is better than those of the ball-milled CeMg{sub 12}-Ni composites. ...
The hydraulic characteristics of flow control multiorifice plate assemblies designed for the FFTF reactor were investigated. The pressure drop flowrate characteristics determined in the test are presented. (JWR)
The divertor collector plate in the INTOR reactor will be subjected to high heat, particle, and neutron fluxes, making it the most severely damaged torus component. The collector plate is composed of a protection plate, which is directly exposed to the particle flux, and a heat sink which provides support for the protection plate and carries the water coolant. The high-Z refractory metals have been considered for use as the protection plate material, and austenitic stainless steels and copper alloys have been considered as the heat sink material. Tungsten and Type 316 stainless steels have been selected for the protection plate and heat sink, respectively. The protection plate has a sputtering lifetime of 1.75 y at a 50% duty factor, while the heat sink is expected to last the lifetime of the reactor.
Reports by U.S. workers on geodetic measurements of recent plate motions or crustal deformation published in 1987-1990 are reviewed. The review begins with global plate motions, proceeds through plate boundaries in California, Alaska, and the Pacific Northwest, and finishes with volcanic phenomena, monument stability and longevity, and GPS relative position measurements. 184 refs.
Wider coal lines and larger power plant units necessitate measures for increasing the capacity of the mills without driving up power consumption and installation costs. The result of this development is the modern ALSTOM bowl mill. This paper indicates the stages of development which were necessary for this and the experience which could be accumulated through these measures. The paper also describes in detail the areas of flow in the mills, of design of milling equipment, of mill power supply and of grading in this development. (orig.) [Deutsch] Breitere Kohlebaender und groessere Kraftwerkseinheiten zwingen zu Massnahmen, um die Leistung der Muehlen zu vergroessern, ohne jedoch den Kraftbedarf und die Installationskosten in die Hoehe zu treiben. Das Ergebnis dieser Entwicklung ist die moderne ALSTOM-Schuesselmuehle. Der Beitrag zeigt, welche Entwicklungsschritte hierzu ...
A transient eddy current measurement method is presented to determine the thickness and conductivity of a conductive plate. The conductive plate is induced by an air-cored coil, the magnetic flux density along the axial is measured and the various signals corresponding to plates with different thickness and conductivity are calculated using a 3D transient eddy current simulator. Characteristic features are obtained from the transient response. A similarity-based modeling method is utilized in this study to estimate the thickness and conductivity of the conductive plate. (author)
An insulated letter drop plate comprises a back plate having an opening for the mail having two hinges at its upper part to attach a cover to; a frame for retaining a first insulation around its perimeter and around the opening; and suitable insulation. This back plate is also provided with an upper curved extension to cover and conceal said hinges. A cover is provided with two complementary hinges to be articulated with the first hinges on the back plate, and with a frame around the perimeter for the retention of a second insulation. A wire joins the first and second hinges, and a coil spring on the wire keeps the cover normally closed.
A fuel plate examination was conducted in the hot cell and canal to determine the possible failure modes for three plates leaking fission products. The plates were irradiated in the Extended Life Aluminide Fuel (ELAF) program in support of university research reactor goals to increase the limits presently allowed. The examination indicated pitting corrosion to be the failure mode. Other failure modes such as: (a) nonbonded swelling, (b) excessive fuel swelling, and (c) overheating of the plates were not observed.
We show that in the Landau gauge of the SU(2) Yang-Mills theory the residual global symmetry supports existence of the topological vortices which resemble disclination defects in the nematic liquid crystals and the Alice (half-quantum) vortices in the superfluid heluim 3 in the A-phase. The theory also possesses half-integer and integer charged monopoles which are analogous to the point-like defects in the nematic crystal and in the liquid helium. We argue that the deconfinement phase transition in the Yang-Mills theory in the Landau gauge is associated with the proliferation of these vortices and/or monopoles. The disorder caused by these defects is suggested to be responsible for the confinement of quarks in the low-temperature phase.
White beam Laue micro-diffraction was performed on directionally solidified, single-crystal Mo pillars in the as-grown state, after focused ion beam (FIB) milling and after pre-straining. The Laue diffraction peaks from the as-grown pillars are very sharp and show no broadening, similar to those from single-crystal Si wafers. Significant broadening and streaking of the peaks occurred after FIB milling and pre-straining, indicative of the damage these treatments induce in the nearly perfect crystal structure of the directionally solidified Mo pillars.
Olive mill effluent (OMW) is an example of a wastewaters containing high concentrations of recalcitrant and toxic compounds which are polyphenolics of different molecular weight. It causes disposal problems because they contain powerful pollutants. Treatment and detoxification of phenolic fraction extracted from olive mill wastewaters as well as a synthetic phenolic mixture was investigated by electro-Fenton method. Results shows that this method is highly efficient in polymerising low molecular mass phenolics and removing a large amount of recalcitrant polyphenolic compounds. This treatment decreased 78% of the toxicity which sustained a good anaerobic post-treatment. (orig.)
Concerning heat transfer augmentation of an axisymmetric impinging jet using a perforated plate set, the bore of the hole in the plate for local and averge heat transfer rate, pitch, and effect of the distance between perforated plate and target plate were examined. Heat transfer augmentation was examined under the condition of 0.063 /ge/d/D /ge/0.200, 1.25 /ge/p/d /ge/4.00, Re is approximately equal to 18000, (where d is the bore of the hole in the plate, D is the axisymmetric nozzle outlet bore, p is the pitch of the perforated plate, and Re is the jet Reynolds number). The findings are as follows; The velocity of the small jet after passing the perforated plate is reduced, and resistance to disturbance is remarkably large. The small jet which is not at the center hole extends to the outside of the plate. The heat ...
... shrouded in secrecy in 2008, Iraq sold its stock of 550 metric tons (in 3,500 barrels) of apparently commercial-grade yellow cake (milled uranium ...
A 206-size hybrid (ceramic/steel) cylindrical roller bearing was tested in MIL-L-23699 C oil at several speeds and loads. Heat-generation data was collected and subsequently correlated with bearing-analysis software. Bearing-cage slip data was also collected at various oil-flow rates, oil temperatures, and with both MIL-L-7808 J and MIL-L-23699 C oils. The hybrid bearing was tested in MIL-L-23699 C oil for for 25 hours at 2220 N radial load and 1.08 MDN shaft speed. The hybrid bearing technology demonstrated in the report is applicable to the Integrated High Performance Turbine Engine Technology Initiative. 15 refs.
The fabrication and characterization of tungsten nanoelectrodes insulated with cathodic electrophoretic paint is described together with their application within the field of neurophysiology....Full Text Available
Off-axis electron holography is used to characterize a linear array of transistors, which was prepared for examination in cross-sectional geometry in the transmission electron microscope (TEM) using focused ion beam (FIB) milling from the substrate side of the semiconductor device. The measured electrostatic potential is compared with results obtained from TEM specimens prepared using the more conventional 'trench' FIB geometry. The use of carbon coating to remove specimen charging effects, which result in electrostatic fringing fields outside 'trench' specimens, is demonstrated. Such fringing fields are not observed after milling from the substrate side of the device. Analysis of the measured holographic phase images suggests that the electrically inactive layer on the surface of each FIB-milled specimen typically has a thickness of 100 nm.
Comparative sequence analysis of the human and the pufferfish Fugu rubripes (fugu) genomes has revealed several novel functional coding and noncoding regions in the human genome. In particular, the fugu genome has been extremely valuable for identifying transcriptional regulatory elements in human loci harboring unusually high levels of evolutionary conservation to rodent genomes. In such regions, the large evolutionary distance between human and fishes provides an additional filter through which functional noncoding elements can be detected with high efficiency.
Tohoku Electric Power Co., Ltd., is now building an LNG-fired No. 4 System (combined cycle of 1.61-million kW) for its Higashi Niigata Thermoelectric Power Station sited in the Niigata East Harbor industrial zone. This is a unit that aims at a thermal efficiency of 50% first in the world by using high-efficiency gas turbines, etc. After the completion of the No. 4 System, the station (No. 1 Machine, No. 2 Machine; No. 3 System, No. 4 System; Harbor No. 1 Machine, Harbor No. 2 Machine) will be generating a total power of 4.6kW, providing the company with its maximum power source which ranks among the largest-grade thermoelectric power stations in this country. Since the construction work was started in April, 1996, approximately 40% had been completed as of March-end, 1997, including foundations for the power station main building, stack, etc. The power station main building uses a raft foundation while the boilers and stack ...
The main purpose of this paper is to explore a numerical algorithm for determining the contact stress when a circular crowned roller is compressed between two plates. To start with, the deformation curve on a plate surface will be derived by using the contact mechanical model. Then, the contact stress distribution along the roller which occurs on the plate surface is divided into three parts: from the center of contact to the edge, the edge and apart from the contact line. The first part is calculated by the elastic contact theorem for the contact subjected to nominal stress between non-crowned parts of roller and plates, the second part is obtained by the classical Hertzian contact solution for the contact between crowned parts of roller and plates, and the third part is simulated as exponential decay. In order to overcome the defect of the half space theorem, in which a ...
An 80 keV, 3.6 MW neutral beam injection system has recently been installed on Doublet III, and the installation of a second system is scheduled within several months. Armor plate consisting of /approximately equals/100 graphite tiles (10 cm x 10 cm) coated with TiC has been plated over portions of the inner vacuum wall lying in the line of sight of the ion sources. In order to monitor the condition of the armor plate an infrared camera and a set of optical pyrometers have been installed alongside the beamline and view the armor plate through a CaF/sub 2/ window. The pyrometers measure the temperature of the armor plate associated with the maximum of the intensity distribution of each ion source.
The present invention concerns a high thermal load heat receiving plate such as a divertor plate of a thermonuclear device. The high thermal load heat receiving plate of the present invention has a cooling performance capable of suppressing the temperature of an armour tile to less than a threshold value of the material against high thermal loads applied from plasmas. Spiral polygonal pipes are inserted in cooling pipes at a portion receiving high thermal loads in the high temperature load heat receiving plate of the present invention. Both ends of the polygonal pipes are sealed by lids. An area of the flow channel in the cooling pipes is thus reduced. Heat conductivity on the cooling surface of the cooling pipes is increased in the high thermal load heat receiving plate having such a structure. Accordingly, temperature elevation of the armour tile can be suppressed. (I.S.).
A description is given of the principal steps involved in `USIMINAS` work roll manufacturing project for its tandem cold mill. The service performance of these rolls was found to be similar to that rolls supplied by traditional manufacturers. (author). 5 refs., 5 figs., 3 tabs.
A new classically stable model of spontaneous compactification is investigated. D=10 dimensional Einstein-Yang-Mills SU(3) x U(1) theory compactifies to CP(3) giving SU(4) x U(1) effective D=4 theory with no tachyons. An effective SU(4) coupling constant is calculated.
In vitro rooting response and indole-3-acetic acid (IAA) levels were examined in two genetically related dwarfing apple (Malus pumila Mill) rootstocks. M.26 and M.9...Full Text Available
Olive oil mill wastewaters (OMW) cause disposal problems because they contain powerful pollutants such as phenolic compounds. Complete biodegradation or removal of these compounds is hardly achieved by a single treatment method. In this work, we investigated 2 integrated technologies for the treatment of the recalcitrant contaminants of OMW, allowing water recovery and reuse for agricultural purposes. (Author)
[1′-14C, 13C6]Indole-3-acetic acid was infiltrated into immature pericarp discs from fruits of tomato (Lycopersicon esculentum Mill., cv Moneymaker)....Full Text Available
... In order to produce organic livestock feed, feed mills must be inspected and certified. If they produce both organic and non-organic feed, they must implement procedures, backed up by records, to prevent the commingling of organic and non-organic feed. This includes steps to clean storage bins and mixing and bagging equipment prior to producing batches of organic feed. Organic feed mills also must prevent ...
The gauge-invariant correlation function for the Yang-Mills field strengths is shown to admit a symmetric decomposition into electric and magnetic components. The spectral weights are seen to obey a sum rule of the superconvergence type, owing to asymptotic freedom. The close relation between the dielectric function, electric-magnetic duality, and the algebra of generalized Chern-Simons charges is illustrated for the linearized Yang-Mills-Higgs system.
Loss of organic matter is one of the main forms of soil degradation in Mediterranean agricultural soils, and external sources of organic matter are required to improve soil properties. the two-phase centrifugation system in the olive-oil extraction industry produces a large amount of olive mill waste sludge (TPOMW) which can be used to add organic C to degraded soils. (Author)
An investigation on the hydrogen generation by reacting ball-milled Mg-based materials in different alcoholic solutions (methanol, ethanol, 2-propanol) was performed. The MgH{sub 2} reactivity in methanol is very low (maximum conversion yield <10%) and no improvement is induced by the ball milling treatment. In contrast, the ball milling affects greatly the Mg reactivity in methanol. The Mg powder milled for 30min displays a maximum conversion yield of 47% compared to 3% for unmilled Mg powder. Its high reactivity is ascribed to the creation of numerous defects and fresh surfaces during the initial stage of the milling process, favoring the corrosion of Mg in methanol. In addition, the presence of water in the methanol solution inhibits drastically the alcoholysis reaction despite its low amount (0.3vol%). The higher hydrogen production is obtained with the composite Mg-10at% ...
We study the high energy behaviour of Yang-Mills theory under the inclusion of gravity. In the weak-gravity limit, the running gauge coupling receives no contribution from the gravitational sector, if all symmetries are preserved. This holds true with and without cosmological constant. We also show that asymptotic freedom persists in general field-theory-based gravity scenarios including gravitational shielding as well as asymptotically safe gravity.
The Co-Si composites with a molar ratio of 2:1 are synthesized by ball-milling method and their potential as negative electrode materials of Ni-MH batteries is investigated. The microstructure, morphology and chemical state of the ball-milled Co-Si composites are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). XRD patterns show that the ball-milled samples for 10 and 20 h contain Co, Si and Co{sub 2}Si phases, and the ball-milled samples for 40 and 60 h are mainly amorphous Co{sub 2}Si alloys. In contrast to the high initial discharge capacity (1012 mAh/g) obtained for the sample ball-milled for 10 h, the discharge capacities of the samples ball-milled for 40 and 60 h are very low. It indicates that the hydrogen storage capacity of pure Co{sub 2}Si alloy is very low. It is found that ...
This thesis consists of three parts. In the first part we review the quantization of Yang-Mills theories and perturbative quantum gravity in curved spacetime. In the second part we calculate the Feynman propagators of the Faddeev-Popov ghosts for Yang-Mills theories and perturbative quantum gravity in the covariant gauge. In the third part we investigate the physical equivalence of covariant Wightman graviton two-point function with the physical graviton two-point function. The Feynman propagators of the Faddeev-Popov ghosts for Yang-Mills theories and perturbative quantum gravity in the covariant gauge are infrared (IR) divergent in de Sitter spacetime. We point out, that if we regularize these divergences by introducing a finite mass and take the zero mass limit at the end, then the modes responsible for these divergences will not contribute to loop diagrams in computations of time-ordered products in either ...
A $200 million paper mill being built in Hagerstown, Md., is expected to produce 150,000 bone-dry short tons per year of de-inked, market-grade pulp for writing and printing paper. The 1st Urban Fibers facility, the largest capital project in Hagerstown's history, is slated for completion in the spring. Landegger Recycled Fiber Corp. will operate and maintain the 200,000-square-foot recycling mill and 60,000-square-foot water reclamation plant. The wastepaper recycling mill plans to minimize waste and pollution by: reclaiming 635 tons per day of 100 percent post-consumer mixed office waste from the solid waste stream; saving more than 16 million cubic feet of landfill area per year; conserving the fiber equivalent of 6,700 trees per day; using no chlorine; saving about 2,000 gallons of water and 4,000 kilowatt hours of electricity per ton of throughput, compared to virgin fiber mills; reusing ...
Described herein are the latest trends in rolling mill facilities toward the 21st. century and new techniques developed by Hitachi Ltd. These cover hot rolling facilities, such as two-stage twin, high crown control-roll cross mill, roll shaping machine and continuous hot rolling systems; cold rolling facilities, such as pickling line-tandem cold mill and other continuous systems; and fine steel rolling facilities, such as roll mill for very small diameter pipes and others to improve productivity and product quality. The other new techniques include systems to pursue reliability and maintainability, in which electric appliances, instruments and computers are integrated, or equipped with built-in large-capacity inverters and drivers. For hot rolling, the above techniques lead to development of a new system named Hi-HOT, which produces high-quality hot coils at a sufficient speed, while keeping rolled ...
This document describes the results of accelerated aging tests to determine the long-term effectiveness of selected impoundment liner materials in a uranium mill tailings environment. The study was sponsored by the US Department of Energy under the Uranium Mill Tailings Remedial Action Project. The study was designed to evaluate the need for, and the performance of, several candidate liners for isolating mill tailings leachate in conformance with proposed Environmental Protection Agency and Nuclear Regulatory Commission requirements. The liners were subjected to conditions known to accelerate the degradation mechanisms of the various liners. Also, a test environment was maintained that modeled the expected conditions at a mill tailings impoundment, including ground subsidence and the weight loading of tailings on the liners. A comparison of installation costs was also performed for the candidate liners. ...
PurposeThe objective of this study is to evaluate the continence rate following reconstruction of the posterior urethral plate in robot-assisted laparoscopic radical prostatectomy...Full Text Available
This frequently-asked-questions feature provides answers about earthquakes, faults, plate tectonics, and earth structure. Maps and diagrams are provided with some answers, and links to additional information and to related topics are included.
This research involves the development of an analysis which yielded recommendations regarding the plate thickness at which the effects of transverse shear become significant enough to be taken into consideration during vibration testing of composite plates. The specimens designed using this analysis are to be used for the {open_quotes}inverse{close_quotes} problem of determining through-the-thickness elastic constants as well as in-plane elastic constants from modal vibration response data. The effects of transverse shear were studied over the range of practical plate aspect ratios (length to thickness ratios) and mode numbers. Behavior of composite plates ranging from isotropic to highly orthotropic was studied in order to investigate the effects of transverse shear. Orthotropic plates having in-plane dimensions of 254 x 254 mm and thicknesses varying from 10 mm to 80 mm, with ...
Tail plates obtained from T4D amber mutants were examined with respect to sedimentation behavior, subunit molecular weights, amino acid composition, isoelectric points, and morphology. Intact plates...Full Text Available
Experimentally it is shown that a movable grounded metallic plate placed inside a multi-dipole magnetic cage can vary the diffused plasma parameters such as density, plasma potential and electron temperature. Plasma is solely produced in the source section of a double plasma device by a dc hot filament discharge and a low-density plasma is produced in the target section by local ionization of neutral gas by the high energetic electrons coming from the source section. A grounded movable stainless steel plate is inserted in the target section of the device. The floating potential of the plate also changes depending on the position of the plate inside the magnetic cage.
We describe a position-sensitive event-counting microchannel plate detector with a quadrant anode readout system that combines the advantages of several centroid-finding readout techniques. The relative amount of charge collected by each quadrant of the anode mounted behind the output side of the microchannel plate is used to localize each event. The position-sensitive area is about 80% of the active microchannel plate surface. By changing a single voltage a remote-controlled image magnification can be achieved. Due to a correction function that minimizes image distortions the imaging characteristics of this low-cost readout system are similar to those of expensive resistive anodes.
... in the design of such devices as fusion reactors, magnetohydrodynamic generators, magnetically levitated vehicles, magnetic forming devices, and ...
We describe a position-sensitive event-counting microchannel plate detector with a quadrant anode readout system that combines the advantages of several centroid-finding readout techniques. The relative amount of charge collected by each quadrant of the anode mounted behind the output side of the microchannel plate is used to localize each event. The position-sensitive area is about 80% of the active microchannel plate surface. By changing a single voltage a remote-controlled image magnification can be achieved. Due to a correction function that minimizes image distortions the imaging characteristics of this low-cost readout system are similar to those of expensive resistive anodes. (orig.).
We describe a position-sensitive event-counting microchannel plate detector with a quadrant anode readout system that combines the advantages of several centroid-finding readout techniques. The relative amount of charge collected by each quadrant of the anode mounted behind the output side of the microchannel plate is used to localize each event. The position-sensitive area is about 80% of the active microchannel plate surface. By changing a single voltage a remote-controlled image magnification can be achieved. Due to a correction function that minimizes image distortions the imaging characteristics of this low-cost readout system are similar to those of expensive resistive anodes.
A flutter-motion equation is presently derived for a 2D composite sandwich panel considering the total lateral displacement of the plate as the sum of the displacement due to bending of the plate, and that which is due to shear deformation at the core. The effects of core thickness and stacking sequence of the faces on the flutter boundary of the plate are discussed; it is shown that the sandwich panel greatly improves the flutter boundary over that of a composite laminate panel, provided it has sufficient core thickness.
After slow progress in the efforts to develop phase plates for electron microscopes, functional phase plate using thin carbon film has been reported recently. It permits collecting high-contrast images...Full Text Available
... The products can be categorised as glazed flat-plate collectors, evacuated glass-tube collectors, and unglazed plastic or low temperature collectors. Glazed flat-plate collectors and vacuum tubes are widely used for solar water heating and space heating systems in all types of buildings. Unglazed plastic collectors are used exclusively for lower temperature applications, such as outdoor swimming pools or the agrarian business. Flat-plate solar collectors are likely to ...
An experimental study was undertaken to determine for the turbulent regime the heat transfer and fluid flow characteristics of a heat exchange array of unperforated, and perforated brass plates with 33% of the plate area open. In both cases, the plates were aligned parallel to the flow direction. For the flow conditions examined, the results showed enhancement of heat transfer and friction factor for the perforated array.
A new dual focal point electro-optic lens that is switchable to focusing and unfocusing is proposed and successfully demonstrated. This electro-optic lens is constructed by coating transparent fine electrodes in the Fresnel-zone plate onto a PLZT ceramic plate. Its focal length changes from 1.25 m to infinity binary at 515 nm with the external voltage of 210 V. PMID:20725208
The purpose of the invention is to improve adaptability of a compression shield to irregularities of a face. This goal is achieved in that a compressible shield is made in the form of a lattice of elastic transverse plates with grooves, elastic vertical elements installed in the grooves, and an elastic plate which is concave toward the face. The plate is located vertically in the middle of the shield. The compressible shield is attached by hinges to a deflector. Telescopic cross pieces are attached by hinges to the covering section of reinforcement, offering the possibility of longitudinal movement at the point of attachment.
Spherical {beta}-Ni(OH){sub 2} was modified by a low-cost method of normal ball milling (NBM), and the physical properties of both ball-milled and un-milled Ni(OH){sub 2} were characterized by transmission electron microscopy, specific surface area, particle size distribution and X-ray diffraction. It was found that NBM could obviously increase the surface area, decrease the particle and crystallite size, and reduce the crystallinity of {beta}-Ni(OH){sub 2}, which were advantageous to the improvement of the electrochemical activity of Ni(OH){sub 2}. NBM also lowered the packing density and flowability of Ni(OH){sub 2}, as revealed by the measurements of tapping density and angle of repose. Electrochemical performances of pasted nickel electrodes with an addition of ball-milled Ni(OH){sub 2} to spherical Ni(OH){sub 2} as the active material were investigated, and were compared with those of the pure ...
A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror thereby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening.
The electroless nickel plating/poly(dl-lactide-co-glycolide) composite coating (EN-plating/PLGA composite coating) was fabricated on the surface of the micro-arc oxidation (MAO) film of the magnesium alloy AZ81 to double control the corrosion and drug release in the hanks' solution. The EN-plating was fabricated on the MAO coating to improve the corrosion resistance by overlaying most pores and micro-cracks on the surface of the MAO film. Meanwhile, a double layered organic poly(dl-lactide-co-glycolide)/paclitaxel (PLGA/PTX) drug releasing coating with a top layered PLGA drug controlled releasing coating on EN plating was prepared to control the drug release rate by adjusting the different lactide: glycolide (LA:GA) ratio of PLGA. Scanning electron microscopy (SEM) and the X-ray powder dif...
We extend a previous result [Phys. Rev. Lett. 105, 090403 (2010)] on Casimir repulsion between a plate with a hole and a cylinder centered above it to geometries in which the central object can no longer be treated as a point dipole. We show through numerical calculations that as the distance between the plate and central object decreases, there is an intermediate regime in which the repulsive force increases dramatically. Beyond this, the force rapidly switches over to attraction as the separation decreases further to zero, in line with the proximity force approximation. We demonstrate that this effect can be understood as a competition between an increased repulsion due to a larger polarizability of the central object interacting with increased fringing fields near the edge of the plate, and attractive forces due primarily to the nonzero thickness of the plate. In comparison with our previous work, we ...
A steadily increasing part of comminution is nowadays carried out by tube ball mills. Our investigations are a first step to a possible tuning of material distribution with mechanical stress characteristic of the grinding media charge, that is essential for a high efficiency of grinding. A BOND mill filled with porcelain balls as grinding media and labelled corundum (Au-198) as grinding material was used to measure the distribution of material over the cross-section. The evaluation was made by linear interpolation between all combinations of adjacent measuring points to calculate all coordinates with equal intensity for each selected level of activity. Two plottings showing the dependence of material distribution on the rotating speed are presented. (author).
A method for systematically including topological degrees of freedom in perturbation theory is developed. This is not bound by the restrictions of semi-classical techniques. The Yang-Mills theory in three Euclidean dimensions is considered here. A well-defined separation of the topological and the ``spin wave'' degrees of freedom is obtained, motivated by a singular gauge. This has ``photons'' distorting the spherically symmetric magnetic fields of Dirac monopoles, and massless charged vector bosons ``W'' scattering off the latter. It is explicitly shown that the Dirac string does not contribute. The mode of the charged vector bosons with total angular momentum J=0 provides precisely the core to give a finite energy to the monopole. The radial equation for W is remarkably simplified and only two polarization states survive exactly for the anomalous magnetic moment required by the Yang-Mills interaction.
Low-porosity #alpha#- and #beta#-SiAlON composite material was prepared when the powder mixture intended for preparation of yttrium #alpha#-SiAlON, with the formula Y_0_._4Si_1_2_-_m_+_nAl_m_+_nO_nN_1_6_- _n, was attritor milled in isopropyl alcohol or contained excess oxygen (n > 0.6). The region of stability of single-phase yttrium #alpha#-SiAlON was smaller at lower temperatures. Wet milling (in isopropyl alcohol) of AlN powder was found to introduce excess oxygen into the milled powder.
The ball-milling method was used to produce Mg-50 wt.% ZrFe{sub 1.4}Cr{sub 0.6} composite. The thermodynamic, kinetic, and cycling properties, as well as the resistance to oxidation were examined. This composite possesses excellent kinetic properties, even at moderate temperature. Scanning electron microscopy, energy-dispersive spectrum, transmission electron microscopy and X-ray diffraction were used to characterize the composite before and after hydriding. The fine ZrFe{sub 1.4}Cr{sub 0.6} particles covering Mg particles acting as a ''catalytic film'', a significant amount of imperfections and some alloy powder in the Mg matrix introduced by ball milling all contributed to the enhanced absorption/desorption rate. (orig.)
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.
The work reported in this paper addresses the problem of structure-borne sound transmission between vibrating sources and ribbed-plate receiver structures. Vibrating sources, such as pumps, motors, fans, etc., transmit vibro-acoustic power, causing noise complaints by occupants in cars, trains, aircraft, buildings and/or material fatigue and damage. The transmission process is complicated in that sources transmit power through several contacts and by up to six components of excitation at each contact. The structure-borne sound power is a function of source activity, source mobility and receiver mobility, and all three quantities must be known to some degree. For non-homogeneous receiver structures, such as thin-plate cavity constructions or lightweight framed constructions, the sheathing plates are typically fastened to the framing members using bolts, screws or spot-welded joints. Hence the resulting system is a ...
The Nilsson Plate High Frequency Adaptation of the Static Electrification Monitor developed by Electric Research and Management, Inc. for EPRI has demonstrated that the Nilsson Plate can be utilized as a practical high frequency antenna to record partial discharge activity within a transformer. Tests in the ABB factory at Muncie, IN on a 650 MVA, 345/20.9 kV, three-phase unit step-up transformer for TU Electric showed the Nilsson plate detecting partial discharge activity. Although this test was the first attempt at using the Nilsson plate in this manner, and in spite of higher than expected electrical noise levels, the data demonstrated that partial discharges can be detected. The tests also demonstrated that corona activity external to the transformer was not recorded by the plate. Some development work needs to be completed to eliminate the noise source from other monitors on the ...
A highly reliable screening method was developed for the determination of lead in tin plated layers and tin-bismuth plated layers. The contents of lead in the layers of the various samples were determined by inductively coupled plasma optical emission spectrometry. The calibration curve for lead in the tin and tin-bismuth plated layers by using WD-XRF exhibited linear correlation from 130 #mu#g/g to 2070 #mu#g/g. Calibration curve of lead normalized with Pb-L#alpha#/Sn-K#alpha# intensity was more linear, and this method was possible to evaluate very small sample. The calibration curve for lead in the tin plated layers by using ED-XRF was good linearly, but it for lead in the tin-bismuth plated layers was affected by Pb-L#alpha# spectrum and Bi-L#alpha# spectrum overlap each other. It was effective for decreasing affect of Bi-L#alpha# spectrum by using curve fitting method. (author)
Lebers hereditary optic neuropathy (LHON), the most frequent mitochondrial disorder, is mostly due to three mitochondrial DNA (mtDNA) mutations in respiratory chain complex I subunit genes: 3460/ND1, 11778/ND4 and 14484/ND6. Despite considerable clinical evidences, a genetic modifying role of the mtDNA haplogroup background in the clinical expression of LHON remains experimentally unproven. We investigated the effect of mtDNA haplogroups on the assembly of oxidative phosphorylation (OXPHOS) complexes in transmitochondrial hybrids (cybrids) harboring the three common LHON mutations. The steady-state levels of respiratory chain complexes appeared normal in mutant cybrids. However, an accumulation of low molecular weight subcomplexes suggested a complex I assembly/stability defect, which was ...
While many attacks are distributed across botnets, investigators and network operators have recently targeted malicious networks through high profile autonomous system (AS) de-peerings and network shut-downs. In this paper, we explore whether some ASes indeed are safe havens for malicious activity. We look for ISPs and ASes that exhibit disproportionately high malicious behavior using 12 popular blacklists. We find that some ASes have over 80% of their routable IP address space blacklisted and others account for large fractions of blacklisted IPs. Overall, we conclude that examining malicious activity at the AS granularity can unearth networks with lax security or those that harbor cybercrime.
Implementation of Title 10 Code of Federal Regulations Part 830, Subpart B Nuclear Safety Management (1) was accomplished at the Waste Isolation Pilot Plant (WIPP) in a timely and efficient manner. The primary reason the transition went smoothly was that the existing safety analysis was relatively new, initially developed in 1995, and written in accordance with the safe harbor document DOE-STD-3009 (2). The WIPP Safety Analysis Report (SAR) (3) is kept up-to-date with the unreviewed safety question (USQ) process and thorough oversight and input provided by DOE-Carlsbad Field Office (CBFO) documented in the annual safety evaluation report (SER) process.
Odontocetes are believed to receive sounds primarily through the pan bone region of the lower jaw although much variation in jaw morphology exists among species. In order to further examine this jaw hearing hypothesis we tested the head receiving sensitivity and directional hearing of a beluga whale, Delphinapterus leucas. Hearing thresholds were measured using auditory evoked potentials (AEPs). The subject proved to have highly directional hearing for far-field click stimuli similar to that of bottlenose dolphins and more directional than the harbor porpoise. For near-field jawphone stimulation, the beluga's lowest thresholds were found when click stimuli were presented at the rostrum tip (76?dB re: 1??Pa) although thresholds from the pan bone region stimulation were only 2?3?dB higher. S...
Prepulse inhibition (PPI) is a measure of sensorimotor gating, a pre-attentional inhibitory brain mechanism that filters extraneous stimuli. Prepulse inhibition is correlated with measures of cognition and executive functioning, and is considered an endophenotype of schizophrenia and other psychiatric illnesses in which patients show PPI impairments. As a first step toward identifying genes that regulate PPI, we performed a quantitative trait locus (QTL) screen of PPI phenotypes in a panel of mouse chromosome substitution strains (CSSs). We identified five CSSs with altered PPI compared with the host C57BL/6J strain: CSS-4 exhibited decreased PPI, whereas CSS-10, -11, -16 and -Y exhibited higher PPI compared with C57BL/6J. These data indicate that A/J chromosomes 4, 10, 11, 16 and Y harbor...
Several lines of evidence are presented that indicate that the level of tetracycline resistance of Esherichia coli strains harboring plasmid pBR322 varies according to whether the SOS system of the host bacteria has been induced. These include use of strains in which the SOS system is expressed constitutively (lexA def.), is thermoinducible (recA441) or noninducible (lexA ind-), or is highly repressed (multiple copies of lexA+). Similar induction was observed with the product of another plasmid gene, beta-lactamase. The amounts of extractable plasmid DNA were also increased by SOS induction, and we propose that the SOS-induced increases in levels of tetracycline resistance and beta-lactamase activity are due to an increased plasmid copy number.
Abstract Alcoa World Alumina Australia mines bauxite under lease agreements with the Government of Western Australia. The leases lie in the Darling Range to the east of Perth, the capital and major population center. In addition to bauxite and other mineral ores, the Darling Range is a major potable water source and harbors a species-rich forest dominated by Jarrah (Eucalyptus marginata), a significant commercial timber. Conservation and recreation are important land uses in the region. Social and political pressures have led to stringent governmental requirements for restoration. In addition, a summer drought period, a soil deficient in most nutrients, water management challenges, an introduced disease, caused by Phytophthora cinnamomi Rands, and a post-mining ecosystem that must be condu...
This study assessed coastal erosion vulnerability along a 90-km sector, which included both erosional and accretionary beaches, and different levels of human occupation. Two aerial photogrammetric flights were used to reconstruct coastal evolution between 1977 and 1999. During this period, extensive accretion was recorded updrift of human structures at harbors and ports, e.g., Scoglitti (105.6?m), Donnalucata (52.8?m), and Pozzallo (94.6?m). Conversely, erosion was recorded in downdrift areas, with maximum values at Modica Stream mouth (63.8?m) and Point Castellazzo (35.2?m). Assessments were subsequently divided into four categories ranging from ?high erosion?? to ?accretion.?? Several sources were examined to assess human activities and land use. The latter was mapped and divided into fo...
Abstract Recent reports showed many patients with chronic fatigue syndrome (CFS) harbor a retrovirus, xenotropic murine leukemia-related virus (XMRV), in blood; other studies could not replicate this finding. A useful next step would be to examine cerebrospinal fluid, because in some patients CFS is thought to be a brain disorder. Finding a microbe in the central nervous system would have greater significance than in blood because of the integrity of the blood-brain barrier. We examined cerebrospinal fluid from 43 CFS patients using polymerase chain reaction techniques, but did not find XMRV or multiple other common viruses, suggesting that exploration of other causes or pathogenetic mechanisms is warranted. Ann Neurol 2011;
Nanocrystalline samples of Fe_8_0Mo_2_0 and Fe_5_0Mo_5_0 alloys were prepared by the mechanical milling method. The structure, lattice parameters, and crystallite size were determined by the X-ray diffraction. The magnetic properties of the milled products were determined by the Moessbauer spectroscopy. It was observed that in the case of the Fe_8_0Mo_2_0 alloy a solid solution of Mo in Fe was formed with the lattice parameters of the Fe increasing from 0.28659 nm to 0.29240 nm and the crystallite size decreasing from 250 nm to 20 nm. In the case of the Fe_5_0Mo_5_0 alloy there were no clear changes in values of the lattice parameters of Fe and Mo during the milling process, but the crystallite size decreased from 200 to 15 nm. Moessbauer spectra revealed different magnetic phases in the machanosynthesized Fe_Mo samples. In the case of the Fe_8_0Mo_2_0 alloy, the spectrum for the milled mixture ...
Thinning specimens to electron transparency for electron microscopy analysis can be done by conventional (2-4 kV) argon ion milling or focused ion beam (FIB) lift-out techniques. Both these methods tend to leave 'mottling' visible on thin specimen areas, and this is believed to be surface damage caused by ion implantation and amorphisation. A low energy (250-500 V) Argon ion polish has been shown to greatly improve specimen quality for crystalline silicon samples. Here we investigate the preparation of technologically important materials for nanoanalysis using conventional and lift-out methods followed by a low energy polish in a GentleMill"T"M low energy ion mill. We use a low energy, low angle (6-8 deg.) ion beam to remove the surface damage from previous processing steps. We assess this method for the preparation of technologically important materials, such as steel, silicon and GaAs. For these materials the ability to ...
An enzyme active against carboxymethyl cellulose (CMC) was purified from the stationary-phase-culture supernatant of Clostridium josui grown in a medium containing ball-milled cellulose. The purification...Full Text Available
Cell suspension cultures of tomato, Lycopersicon esculentum Mill. cv VFNT-Cherry, produce phytochelatins (poly[γ-glutamylcysteinyl]glycines) when exposed to cadmium. The synthesis...Full Text Available
Ultra fine tungsten carbide and cobalt powders were milled by high energy planetary ball mill at different ball to powder weight ratios (BPR) to produce particles of WC-10wt%Co hard metal in nanometer scale size. Microstructural characterizations by TEM show that the particle size of tungsten carbide was achieved to 32nm after milling at 15 BPR during 10h. In order to reduce the WC grain growth during the sintering process, tantalum carbide was added to the hard metal as a WC grain growth inhibitor. The nano hard metal powders were compacted at 200MPa pressure and sintered at 1370-1450degreeC temperatures in a high purity hydrogen atmosphere. The results show that the addition of 0.6wt% of TaC improves the hardness and fracture toughness from 1493 HV30 and 11.8MPam (for TaC free sample) to...
The optimizing criterion is assumed to be the maximum net present value of the project. The following summarizes the significant conclusions. (1) Over a large range of discount rates, mining and milling of the mineral deposit at a constant cutoff grade and a constant production rate consistently results in smaller annual discounted cash flows than the optimal schedule determined by the dynamic programming model (dpm) where the cutoff grade and mining rate are allowed to vary in response to fluctuating product price. (2) With an increasing discount rate, under the dpm the annual discounted cash flows decrease at a slower rate than if the mineral inventory is mined and milled at a constant cutoff grade and a constant production rate. (3) Cuttoff grade increases only where higher equity ore is available. Thus, to maintain the mill feed requirement, the mining rate also increases. (4) Not withstanding an anamolous mineral ...
Recent studies have revealed a number of striking dependence patterns in high frequency stock price dynamics characterizing probabilistic interrelation between two consequent price increments x (push) and y (response) as described by the bivariate probability distribution P(x,y) [1,2,3,4]. There are two properties, the market mill asymmetries of P(x,y) and predictability due to nonzero z-shaped mean conditional response, that are of special importance. Main goal of the present paper is to put together a model reproducing both the z-shaped mean conditional response and the market mill asymmetry of P(x,y) with respect to the axis y=0. We develop a probabilistic model based on a multi-component ansatz for conditional distribution P(y|x) with push-dependent weights and means describing both properties. A relationship between the market mill asymmetry and predictability is discussed. A possible connection of the model to ...
After preparation on self-generated Percoll gradients, avocado (Persea americana Mill, var. Fuerte and Hass) mitochondria retain a high proportion of cyanide-insensitive respiration,...Full Text Available
... on a transgressive surface; examples from the Silurian Whirlpool Sandstone of southern Ontario, Canada. Journal of Sedimentary ... and C. J. Salas. 1991. The Lower Silurian Whirlpool Sandstone. in Cheel, ...
Focused-ion beam (FIB) milling provides rapid fabrication of individual cylindrical submicrometer channels with reproducible dimensions (#+-#5% diameters) through 8-#mu#m thick poly(methylmethacrylate) (PMMA) films. PMMA films are spincast on sacrificial Si carriers and sputter-coated with Au before the 30-kV gallium FIB milling process. By adding a trace amount of poly(ethyleneoxide) and poly(dimethylsiloxane) to the PMMA solution before casting, the films can be released for subsequent mounting in microfluidic devices to create hybrid microfluidic-nanofluidic multilevel architectures. In situ FIB sectioning demonstrates the smooth cylindrical surface within the pore. Placing a milled film in contact with an aqueous fluorescein solution fills the channel by capillary action, as verified by confocal fluorescence microscopy. Confocal fluorescence of dyed films reveals that the pores span the thickness of the PMMA film. Small ...
Workers from cotton mills were exposed to cotton dust during carding in an experimental cardroom. Cotton from different geographical locations with varying amounts of endotoxin were used. Exposure levels...Full Text Available
The following manual chapters are outlined and described: overview, boilers, juice evaporators, feed mills, refrigeration, additional energy savings potentials, emerging technologies, optimization of integrated plant energy systems, and economics. (MHR)
AT AFRICA (O.F.) AIDO1 SYMMES CREEK AT AID ALLO1 MAHONING RIVER AT ALLIANCE ALZO1 ALEXANDRIA AMDO1 AMSTERDAM ARMO1 CAPTINA CREEK AT SR 148 AT ARMSTRONG MILLS ASVO1 WALNUT CREEK...
BackgroundLignocellulosic biomass such as wood is an attractive material for fuel ethanol production. Pretreatment technologies that increase the digestibility of cellulose and hemicellulose...Full Text Available
An extracellular polysaccharide was purified from culture supernatants of Paenibacillus jamilae CP-7, a gram-positive bacillus that was isolated from compost prepared with olive mill...Full Text Available
Gravitropic asymmetry of auxin was observed in hypocotyls of tomato (Lycopersicon esculentum Mill.) soon after horizontal placement: the ratio of apically supplied [3H]IAA...Full Text Available
Hundreds of thousands of people worldwide live or work in close proximity to steel mills. Integrated steel production generates chemical pollution containing compounds that can induce genetic damage...Full Text Available
Lycopersicon esculentum Mill. cv Vedettos and Lycopersicon chmielewskii Rick, LA 1028, were exposed to two CO2 concentrations (330 or 900 microliters per...Full Text Available
In this work, the effects of the focus ion beam (FIB) milling process on the optical properties of semiconductor nanostructures were investigated. With this aim, a sensitive materials system based on InGaAs/GaAs quantum dots with well known and excellent optical properties was selected for the FIB treatment. The FIB technique was used to locally remove a metallic mask deposited on top of the quantum dot sample. The photoluminescence (PL) signal, collected from the circular openings, was used to infer the possible damage effects of the ion beam on the properties of the dots.
Advanced techniques for focused-ion-beam (FIB) device modification have been developed for complex, multistep modifications to circuitry on planar chip technology. Applying gas-assisted etching (GAE) techniques for high-aspect-ratio milling and the selective milling of both conductive and insulating films enhances process latitude. Localized ion-beam-induced deposition of an insulating film provides reconstructive capability in previously modified areas. The application of both techniques for complex device modification on VSLI devices fabricated with CMOS process technology is reviewed. (UK).
By treatment with beta or gamma rays, PTFE waste is converted to high-grade PTFE fine powder. High-molecular weight PTFE is degraded to low-molecular weight PTFE. Due to this the density, the degree of crystallinity, and the melt flow index are increased, which enhances the brittleness of the material. Irradiation of PTFE thus facilitates milling and makes the material pourable and free-flowing. Milled PTFE fine powder, lie PTFE plastic, combines temperature resistance, weather fastness, and chemical stability with good slip behaviour and antiadhesive properties. Areas of application for fine powder include additives for plastics, printing inks, nonstick coatings, and antifriction lacquers. (orig.).
By employing the higher dimensional version of the Wu-Yang Ansatz we obtain magnetically charged new black hole solutions in the Einstein-Yang-Mills-Lovelock (EYML) theory with second ($\\alpha2$) and third ($\\alpha3$)order parameters. These parameters, where $\\alpha2$ is also known as the Gauss-Bonnet parameter, modify the horizons (and the resulting thermodynamical properties) of the black holes. It is shown also that asymptotically, these parameters contribute to an effective cosmological constant -without cosmological constant- so that the solution behaves de-Sitter (Anti de-Sitter) like.
The use of uranium mill tailings in the foundations of dwellings has resulted in indoor radon progeny concentrations and gamma exposures in excess of levels presently allowed for the general public. An account is given of the applications of an epoxy coating on the indoor faces of the concrete foundations of three buildings in Grand Junction, Colorado. Epoxy barriers were shown to be effective for preventing radon influx into structures. Gamma exposure rates must be analyzed to ensure that buildup behind the barrier will not introduce an unacceptable gamma exposure level. The use of a sealant is especially economical in situations where structural integrity may be jeopardized by physical removal of uranium mill tailings. (author).
Five nomographs have been prepared that facilitate the estimation of cover thickness and cover material volume for the Uranium Mill Tailing Remedial Action Program. Key parameters determined include the cover thickness with either a surface radon flux or a boundary radon air concentration criterion and the total volume of cover material required for two different treatments of the edge slopes. Also included in the engineering guide are descriptions and representative values for the radon source term, the diffusion coefficients and the key meteorological parameters. 16 refs., 7 figs., 2 tabs.
The effects of catalytic metal additives on the hydrogen desorption properties of the submicrocrystalline magnesium hydride (#beta#-MgH_2) formed after hydrogenation of the Mg + 10 wt.%X (X = V, Y, Zr) mechanically (ball) milled composites were studied. The composites with catalytic metals were processed by controlled mechanical milling (CMM) in the magneto-mill Uni Ball Mill 5 under protective Ar atmosphere. X-ray diffraction of the milled powders revealed the formation of Mg nanograins (50-60 nm range) interdispersed with the nanograined metal additives within the powder particles. Scanning electron microscopy showed particle size reduction after milling. After activation and hydrogenation in a Sieverts-type apparatus under about 2 MPa pressure of hydrogen, the tetragonal #beta#-MgH_2 hydride co-exists with the small amount of retained unreacted Mg phase and ...
The Prince William Sound Regional Citizen's Advisory Council and the Cook Inlet Regional Citizen's Advisory Council are independent, non profit organizations formed in 1989 following the Exxon Valdez oil spill to promote the concept of community-based oil spill response (COSR) in their respective regions. COSR involves local citizens in responding to oil spilled in waters they rely upon for income, recreation and subsistence. The 2 advisory councils recently held a Community Oil Spill Response Forum to review the status of existing COSR teams and to share information about past and future COSR-related efforts. The meeting served as an information exchange process about regulatory programs, COSR variations in communities and harbors, training, and personnel issues. Key groups attending the forum were harbor masters, Alaska Department of Environmental Conservation, United States Coast Guard, existing COSR teams, oil response ...
Natural convection flow is established in KMRR (Korea Multi-Purpose Research Reactor) reflector tank at the loss of reflector circulator. To simulate the reflector tank natural convection flow with high temperatures at the inner shell and bottom plate due to nuclear heating, experimental and numerical studies in an open cavity with 'L' type heated wall made by the combination of a vertical and horizontal plate were performed. It was confirmed through these studies that the heat transfer rates were highest at the lower region of the vertical plate and the inlet region of horizontal plate and comparatively high at the middle portion of both plates. The heat transfer rate distribution of this trend shows a desirable trend for the effective natural convection cooling of KMRR reflector tank. It was also confirmed that the average Nusselts numbers at the 'L' type heated wall were lower ...
With a pilot electrostatic precipitator having wider plate spacings than usual tests were performed under industrial conditions. In the two-section two-duct pilot precipitator with a precipitation area of 60 m/sup 2/ the plate spacing was increased up to 1,000 mm. As gas velocities values between 0.5 and 2.0 m/s were selected. The precipitator was tested with the flue gases of a coal-fired power station and in the room dedustion of an iron ore sintering plant. Starting with a plate spacing of 250 mm increasing the spacing results initially in a small increase of the precipitation rate. After reaching a maximum the rate decreases and finally with passing a critical spacing it goes below the initial value. Dedusting flue gases the spacing with the maximum and the critical spacing depend on the gas velocity. Cost analyses demonstrate that increasing the up to now used plate spacings may led to considerable ...
An attempt is made to augment the heat transfer efficiency by means of inserting an oscillating thin plate into a tube of the shell and tube heat exchanger. However, the heat transfer augmenting mechanism has not been fully explained. To elucidate this heat transfer augmenting mechanism, an investigation was given on the heat transfer characteristics of a tube inlet at its preliminary run area when a double-hinged oscillating thin plate is inserted in the inlet. As a result of the experiment, the heat transfer augmentation in the tube as a result of inserting the double-hinged oscillating thin plate was found effective when the preliminary inlet run area is treated as the object. However, in comparison of the effect with the heat transfer in a fully developed turbulent region, it was {eta}- 1. The result thus obtained explains that no sufficient turbulence can be obtained when the deflection angle of the first oscillating ...
This paper reports on the detection of optical novae in our neighbour galaxy M31 based on digitized historical Tautenburg Schmidt plates. The accurate positions of the detected novae lead to a much larger database for searches for recurrent novae in M31. We conducted a systematic search for novae on 306 digitized Tautenburg Schmidt plates covering a time span of 36 years from 1960 to 1996. From the database of both ~ 300 000 light curves and about one million detections on only one plate per colour band, nova candidates were efficiently selected by automated algorithms and subsequently individually inspected by eye. We report the detection of 84 nova candidates. In detail we found 55 nova candidates from the automated analysis of the light curves. Among these, 22 were previously unknown, 12 were known but have not been identified on Tautenburg Schmidt plates before and 21 novae have been discovered on ...
The refrigerant two-phase flows in a distributor and a simulated plate heat exchanger with a single passage used in a compression-type refrigerator were visualized by real-time neutron radiography. For a distributor, the liquid fraction in the each tube was measured by some image processing method. On the other hand, for a plate heat exchanger, the two-dimensional distribution of void fraction was measured quantitatively by the umbra method. As a result, it was shown that the dynamic behaviors of refrigerant at the inlet of the section strongly affected on the performance, that is, a distribution performance of a distributor and a liquid distribution in a plate heat exchanger. (author)
Solid-state acoustic sensors for monitoring conditions at a surface immersed in a liquid and for monitoring concentrations of species in a liquid and for monitoring electrical properties of a liquid are formed by placing interdigital input and output transducers on a piezoelectric substrate and propagating acoustic plate modes therebetween. The deposition or removal of material on or from, respectively, a thin film in contact with the surface, or changes in the mechanical properties of a thin film in contact with the surface, or changes in the electrical characteristics of the solution, create perturbations in the velocity and attenuation of the acoustic plate modes as a function of these properties or changes in them.
This paper provides information on activities undertaken in a non- production oriented metal finishing operation to minimize waste and conserve resources. The facility is a 6000 sq foot shop that typically only deals with prototype parts. Utilizing a plan that includes employee awareness, common sense and existing technology, a noticeable reduction in waste volume has been obtained. Initiatives that are covered include: segregation of cyanide plating solutions, elimination of copper cyanide plating, elimination of hexavalent chromium plating, elimination of vapor degreasing, changing of rinsing practices, and changing a process for cleaning of aluminum parts. Some discussion is also presented on the effectiveness of combining the technologies of physical vapor deposition and electrodeposition to help minimize waste. Plans for additional initiatives including water recycling, elimination of cyanide ...
Plate-boundary earthquakes have occurred repeatedly in the past several thousand years at the Cascadia subduction zone, where they are widely recorded ... ...
A photoacoustic (PA) imaging system based on an ultrasonic Fresnel zone plate (FZP) transducer is developed for the purpose of imaging biological tissue. This FZP transducer has a two-zone negative zone plate piezoelectric material pattern, and an optical fibre is integrated with the transducer on the symmetric axis of the zone plates to deliver laser pulses to the sample. The focal characteristic of the FZP transducer is analysed by theoretical prediction and experimental measurement, and the measured results are in good agreement with the predicted results. The limited-field back-projection deconvolution algorithm combined with the coherence-factor weighting technique is used to reconstruct the optical absorption distribution. The experiments were performed with phantoms and the blood vessels of chicken embryo chorioallantoic membrane. The results demonstrate that PA imaging using the FZP transducer has the ability to ...
In the frame of the Primary Wall Module prototype manufacturing for ITER, a consistent R and D phase was conducted in order to identify the industrial allowable tolerances and manufacturing problems which would occur when joining pieces by HIPping process during the PW module manufacturing. The purpose of this development was to give as industrial as possible manufacturing routes for joining together large Stainless Steel or DS-Copper pieces with Stainless Steel tubes and for bonding Beryllium tiles onto a curved component surface. The study concerned surface preparations, allowable gaps and joint geometry, Beryllium tile geometry, Titanium interlayer thickness, etc. This R and D phase also allowed the development and validation of different ultrasonic inspection tools needed for plate-plate, tube-plate, edge to edge plate bonding.
Apr 18, 2008 ... The FSS was produced by point-source filtering the individual detector data ... a 1-sigma noise map; and a coverage map giving the count of ...
The steam generator inspection and maintenance device has an articulated arm formed at least by two rigid segments connected by a pivot and two plates on the ends of the arms by articulated joints which enable them to rotate about two orthogonal axis. One of the axis is parralel to the axis of the pivot between the arm sections while the other is perpendicular to the surface of the corresponding plate. Each of the plates carries coupling elements which are able to engage with the perforations of the heat exchanger tube plates and also a support for a maintenance tool.
PurposeWe objectively quantified the gain in urethral diameter and the effect of stenting after tubularized incised plate urethroplasty in a rabbit hypospadias model. Materials and MethodsWe created a hypospadias model in 12 New Zealand white male rabbits by excising the ventral urethra. A 3 cm tattoo line was made longitudinally in the dorsal urethral plate midline. Two weeks later a 2 cm relaxing incision was made in the middle part of the tattooed line. The stretched incision width between the tattooed edges was measured, followed by urethral plate tubularization. Six rabbits were stented and 6 were nonstented. Two weeks later the animals were sacrificed and the distance separating the tattoo was measured at the midpoint of the tattooed line. Transverse sections at this point were exami...
A numerical analysis is made of the unsteady flow and heat transfer characteristics of mixed convection in a vertical block-heated channel with and without installing an inclined plate above an upstream block. Parameter studies including the inclined plate angle, Reynolds number (ranging from 260 to 530), and Grashof number (in the range of 0--3,200,000) on heat transfer performance have been explored in detail. The results show that the installation of an inclined plate in the vertical block-heated channel can effectively augment the blocks` heat transfer performance in the channel. This can be applied to heat exchangers.
This paper presents the experimental results of heat transfer augmentation in an axisymmetric jet impinging normally on a flat plate surface without the requirement of additional pumping power. The present technique of augmentation utilizes only a punched plate with circular holes arranged in a triangular array, fixed parallel to, just in front of the heated target plate. Near the optimum conditions determined, the heat transfer coefficient at the geometrical stagnation point can be increased 4 times. Additional flow visualization study indicates that this augmentation mechanism creates an improved flow field where the punched plate acts as a detached fin, the conductivity of which may be exploited for further augmentation. Besides augmentation, the present investigation foresees the possibility of manipulating the distribution of local heat transfer rate by varying few parameters.
We present first worldline numerical results for the nontrivial interplay between geometry and temperature dependencies of the Casimir effect. We show that the temperature dependence of the Casimir force can be significantly larger for open geometries (e.g., perpendicular plates) than for closed geometries (e.g., parallel plates). For surface separations in the experimentally relevant range, the thermal correction for the perpendicular-plates configuration exhibits a stronger parameter dependence and exceeds that for parallel plates by more than an order of magnitude at room temperature. This effect can be attributed to the fact that the fluctuation spectrum for closed geometries is gapped, inhibiting the thermal excitation of modes at low temperatures. By contrast, open geometries support a thermal excitation of the low-lying modes in the gapless spectrum already at low temperatures.
... Problem: At a glass ceramic cooktop plant, workers manually lift uncut plates of glass onto a waist-high conveyor belt, where it is then stacked ...
Due to the serovar diversity in Haemophilus (H.) parasuis, it is difficult to develop a universal serological method for detection of this pathogen....Full Text Available
... this correction results In only a email error, since the isothoraal tests wore run at roon tomporcturo, -nd simplifies the reduction of isotherme! ...
Single phase amorphous Al_xHf_1_0_0_-_x alloys with a wide amorphization range (33#<=#x#<=#75) were synthesized by the solid-state interdiffusion of pure polycrystalline Al and Hf powders at room temperature using a rod-milling technique. The mechanisms of metallic glass formation and competing crystallization processes in the mechanically deformed composite powders were investigated by means of X-ray diffraction, differential thermal analysis, scanning electron microscopy and transmission electron microscopy. The numerous intimate layered composite particles of the diffusion couples that formed during the first and intermediate stages of milling (0-173 ks) are intermixed to form amorphous phase(s) upon heating to about 980 K by so-called thermally assisted solid-state amorphization (TASSA). The amorphization heat formation for the binary Al_xHf_1_0_0_-_x system via TASSA, #DELTA#H"T"A"S"S"A_a, was measured directly as a function of the ...
The Maybell uranium mill tailings site is 25 miles (mi) (40 kilometers [km]) west of the town of Craig, Colorado, in Moffat County, in the northwestern part of the state. The unincorporated town of Maybell is 5 road mi (8 km) southwest of the site. The designated site covers approximately 110 acres (ac) (45 hectares [ha]) and consists of a concave-shaped tailings pile and rubble from the demolition of the mill buildings buried in the former mill area. Contaminated materials at the Maybell processing site include the tailings pile, which has an average depth of 20 feet (ft) (6 meters [m]) and contains 2.8 million cubic yards (yd{sup 3}) (2.1 million cubic meters [m{sup 3}]) of tailings. The former mill processing area is on the north side of the site and contains 20,000 yd{sup 3} (15,000 m{sup 3}) of contaminated demolition debris. Off-pile contamination is present and includes areas adjacent to the ...
Three model boilers, manufactured to simulate full-size tube sheet crevices, were tested with various secondary side environments. The first was faulted with organics representative of the decomposition of humic acid. The second was faulted with sodium carbonate and sodium hydroxide, while the third was faulted with sodium sulfate and sodium hydroxide. Each model contained seven tubes, which included Alloy 600 in the mill-annealed (MA) and thermally-treated (TT) conditions and Alloy 690 in the thermally-treated condition. Two models contained Alloy 800 tubes in the mill-annealed condition and one had Alloy 800 in the mill-annealed/cold-worked/glass-bead-peened condition. Two different sizes of tubesheet crevices were used in all model boilers. In the organics-faulted boiler, tubes of Alloy 600MA, Alloy 690TT and Alloy 800MA experienced no significant intergranular attack (IGA); however, the Alloy 600TT had intergranular ...
Three model boilers, manufactured to simulate full-size tube sheet crevices, were tested with various secondary side environments. The first was faulted with organics representative of the decomposition of humic acid. The second was faulted with sodium carbonate and sodium hydroxide, while the third was faulted with sodium sulfate and sodium hydroxide. Each model contained seven tubes, which included Alloy 600 in the mill-annealed (MA) and thermally-treated (TT) conditions and Alloy 690 in the thermally-treated condition. Two models contained Alloy 800 tubes in the mill-annealed condition and one had Alloy 800 in the mill-annealed/cold-worked/glass-bead-peened condition. Two different sizes of tubesheet crevices were used in all model boilers. In the organics-faulted boiler, tubes of Alloy 600MA, Alloy 690TT and Alloy 800MA experienced no significant intergranular attack (IGA); however, the Alloy 600TT had intergranular ...
Amorphous materials in the system xLi{sub 2}S{center_dot}(100-x)SiS{sub 2}, where x ranged from 50 to 70 mol %, and (100-y) (0.6Li{sub 2}S{center_dot}0.4SiS{sub 2}){center_dot}yLi{sub 4}SiO{sub 4}, where y ranged from 0 to 10 mol %, were synthesized by mechanical milling of crystalline starting materials, Li{sub 2}S, SiS{sub 2} and Li{sub 4}SiO{sub 4}. At the compositions with large amounts of Li{sup +} ions, a part of crystalline Li{sub 2}S used as a starting material remained in the milled powder samples. It was found that the milled powder samples in both systems obtained by mechanical milling exhibited high conductivities in the order of 10{sup -4}S{center_dot}cm{sup -1} at room temperature in spite of the presence of small amounts of Li{sub 2}S crystals. The conductivity values of the pelletized samples of xLi{sub 2}S{center_dot}(100-x)SiS{sub 2} powders maximized at the composition of about x=60. ...
Intermetallic compounds based on the Al-Co system were synthesized by solid state method - mechanical alloying and their properties were investigated using XRD, SEM, and DSC. The powder was used to make new targets of irradiation for gamma sources in order to enhance the specific activity and to reduce the consumption of material. The intermetallic compound AlCo was formed in the first 4 hours of milling. After 8 hours of milling the medium size of crystallites were of 5.58 nm. This value decreases with the increase of milling time up to 3 nm, corresponding to the 28 hours of grinding. There was calculated and plotted the Gibbs function, #DELTA#_f"0, for the reaction of formation AlCo and Al_3Co from the Al-Co system. It had negative values over the entire range of temperatures for both investigated compounds. After 28 hours milling a phase composition was obtained as follows: 0.2% Al; 21%Co ; ...
A simple and effective method is presented for the sizing and passage apportionment of multistream plate-fin heat exchangers. Methods for passage arrangement are discussed, and it is shown that a symmetric or mixed passage arrangement is more efficient than a segregated arrangement. A method for assessing the relative merits of various passage arrangements is presented. The use of the methods is illustrated through a worked example.
A nozzle plug for blocking a nozzle in a nuclear steam generator is improved by the addition of hinges which allow the nozzle plug to be inserted into the steam generator through an access port of substantially smaller diameter than the nozzle. A recess is provided in one of the semi-circular plates allowing the plates to nest, further reducing the necessary size of the access port.
A new algorithm for the treatment of sliding interfaces between solids with or without friction in an Eulerian wavecode is described. The algorithm has been implemented in the two-dimensional version of the CTH code. The code was used to simulate penetration and perforation of aluminum plates by rigid, conical-nosed tungsten projectiles. Comparison with experimental data is provided.
Magnetic field, thickness and magnetic forming effect on general mode and quantitative parameters of the domain structure (DS) of ferrite-garnet (EuEr)/sub 3/(FeGa)/sub 5/O/sub 12/ monocrystalline plates (111) is investigated. Field interval of circle (cone) and ring domain stability is determined. It is shown that DS of ferrite-garnet crystals with uniaxial an6sotropy has some peculiarities, that can be explained by cubic anisotropy effect.
We performed biomechanical comparison of a xenograft bone plate-screw (XBPS) system for achieving cadaveric lumbar transpedicular stabilization (TS) in dogs. Twenty dogs' cadaveric L2-4 lumbar...Full Text Available
A zinc-air battery in a case including a zinc particle bed supported adjacent the current feeder and diaphragm on a porous support plate which holds the particles but passes electrolyte solution. Electrolyte is recycled through a conduit between the support plate and top of the bed by convective forces created by a density of differential caused by a higher concentration of high density discharge products in the interstices of the bed than in the electrolyte recycle conduit.
A zinc-air battery in a case is described including a zinc particle bed supported adjacent the current feeder and diaphragm on a porous support plate which holds the particles but passes electrolyte solution. Electrolyte is recycled through a conduit between the support plate and top of the bed by convective forces created by a density of differential caused by a higher concentration of high density discharge products in the interstices of the bed than in the electrolyte recycle conduit. 7 figures.
Velocity field behind a flat plate, placed near the wall in a narrow channel as a simulant of a BWR fuel spacer, was measured by using a hot wire anemometer. It was found that not only the positions where the dead water region behind flat plate disappeared but also the locations where the velocity relaxation completed were almost independent of the width of the clearance, although the local average velocity and velocity fluctuation immediately downstream the flat plate were affected by the difference in the clearance. The transverse flow diversions in the channel cross section were evaluated from the shape of the average velocity profile. The decrease of local flow rate near the channel wall, which may causes the drift flow behind a flat plate, was encouraged as the drag of clearance increased. Attempts have been made to measure spanwise velocity in the narrow channel. A spanwise velocity that occurred ...
The corona wind caused by nonuniform electric fields has been experimentally reported so far to be effectively applicable to heat transfer augmentation. In this paper, first, a theoretical and experimental study has been conducted to make clear such a mechanism of augmentation of heat transfer to a downward-facing flat plate due to a nonuniform electric field caused by a fine wire anode and a plate cathode as that ions produced near the wire electrode move to the plate introducing the bulk convective motion of fluid caused by collision of ions and neutral molecules. Secondly, experiments have been carried out by using twin and multi-wire electrodes and the plate to find the augmentation performance of heat transfer for the number and the arrangement of the wire electrodes, to explain the performance from the electrohydrodynamical standpoint based on the theoretical investigation and to obtain important ...
The purpose of the study is to investigate the heat transfer augmentation method for a wavy channel type heat exchanger. Experimental studies were carried out, by installation of flow guide-plates with simple structure, to clarify the effects on the augmentation whether the effects are brought by the flow acceleration or by the increase of intensity of turbulence due to the flow seperation, and to determine optimum shape of flow guide-plates. The shape and dimensions of the experimental apparatus are as follows; channel width H of 30 mm, rectangular section with breadth of 300 mm, wavy duct with a bend angle of 60/sup 0/ and straight pipe of 2H length. Air stream was flowed through the duct with Reynolds number of 1.7 x 10/sup 4/ only. As the results, following conclusions were obtained. (1) Wavy duct with large bend angle and without inserting flow guide-plates could not be expected large effects on the heat transfer ...
A numerical study of laminar flow and heat transfer in an array of stacked rectangular plates is presented. The array is placed in a uniform stream, and the plates are subjected to a constant surface heat flux. This flow configuration is relevant to a number of practical heat transfer devices with finned surfaces. The computations were performed using a finite volume solution of the steady, two-dimensional Navier-Stokes equations and energy equation. A numerical scheme that reduces numerical diffusion is used to discretize the equations. The dominant feature of the flow is the separation, and subsequent reattachment of, the boundary layer, which takes place at Reynolds numbers greater than about 75. The separation first occurs downstream of the leading edge of the plate; then as Re increases, the separation point moves upstream and remains fixed at the leading edge, and the reattachment length increases linearly with Re. ...
In portal images with high energy X-ray (10 MV), it is sometimes difficult to verify the irradiation field because of the low contrast. Especially, in the abdominal and pelvic region, the deterioration of portal image quality is remarkable. To solve this problem, we took portal images using computed radiography (FCR). Also, we develop a technique in which a copper plate (3 mm) and lead foil (0.3 mm) are closely set in the front and rear of the photostimulable phosphor plate (imaging plate), for increased energy absorption. As a result, image quality was very high and we confirmed image improvement using observer performance experiments. We made a special cassette which can closely set metallic plates to imaging plate and load FCR-7000 directly. Therefore, image process becomes simple, and suitable for routine work. In computed radiography, image processing (tone scale modification ...
In portal images with high energy X-ray (10 MV), it is sometimes difficult to verify the irradiation field because of the low contrast. Especially, in the abdominal and pelvic region, the deterioration of portal image quality is remarkable. To solve this problem, we took portal images using computed radiography (FCR). Also, we develop a technique in which a copper plate (3 mm) and lead foil (0.3 mm) are closely set in the front and rear of the photostimulable phosphor plate (imaging plate), for increased energy absorption. As a result, image quality was very high and we confirmed image improvement using observer performance experiments. We made a special cassette which can closely set metallic plates to imaging plate and load FCR-7000 directly. Therefore, image process becomes simple, and suitable for routine work. In computed radiography, image processing (tone scale modification ...
This study evaluates the degree to which surface impoundments at licensed facilities comply with significant changes in NRC requirements initiated by enactment of EPA's final environmental standards for uranium recovery facilities (40 CFR Part 192). Impoundment liner requirements, ground-water protection standards, ground-water monitoring and corrective action programs, and site closure standards are the most significant regulatory modifications. The compliance status of 30 conventional mills and 31 in-situ mines is determined from a review of Nuclear Regulatory Commission and agreement state docket files through November, 1983. Results of this review show that a majority of conventional uranium mill tailings management systems are deficient with respect to liner requirements for new impoundments or proposed expansions to existing impoundments, as well as with respect to some aspects of ground-water monitoring and compliance programs. ...
Focused Ion Beam (FIB) milling is a powerful tool to produce ordered magnetic nanostructures. However, it is impossible to produce out-of-plane magnetized nanoscale structures from multilayer films by direct FIB writing. Co/Pt multilayers exhibit an out-of-plane easy axis due to strong perpendicular interface anisotropy. The interface contribution is known to be very sensitive to high energy ion irradiation. In case of 30 keV Ga ions it needs less than one ion per 100 surface atoms to destroy the perpendicular interface anisotropy. We demonstrate how this problem can be overcome by milling a Co/Pt multilayer, which has been deposited on a SiN membrane, from the rear side, through the SiN. The effect of the ions is determined as a function of applied dose utilizing the domain structure imaged by soft X-ray holography. When the magnetic material is removed we find only a very narrow range of destruction around the holes in contrast to the ...
Nanocrystalline cemented tungsten carbide has attracted considerable interests for use in cutting tool because of its superior mechanical properties. In this study, nano-sized powders of mixed WC and Co were prepared from attrition-milled oxides by a gas reduction-carburization process. The effects of compacting pressure, heating schedule, additional ball-milling, and the presence of a grain growth inhibitor on the sintering properties of the nano-sized WC-Co powders were examined. The grain size and phases in WC-Co alloy were clearly affected by compacting pressure. Because of the trapped gases and the lower melting point of the cobalt binder, when a compact of nano-sized WC-Co powder was sintered through a heating schedule with holding steps, the sintered alloy maintained the small size of WC grains without any {eta} phase. In addition, the additional ball-milling improved the microstructure and mechanical properties of ...
Nanocrystalline cemented tungsten carbide has attracted considerable interests for use in cutting tool because of its superior mechanical properties. In this study, nano-sized powders of mixed WC and Co were prepared from attrition-milled oxides by a gas reduction-carburization process. The effects of compacting pressure, heating schedule, additional ball-milling, and the presence of a grain growth inhibitor on the sintering properties of the nano-sized WC-Co powders were examined. The grain size and phases in WC-Co alloy were clearly affected by compacting pressure. Because of the trapped gases and the lower melting point of the cobalt binder, when a compact of nano-sized WC-Co powder was sintered through a heating schedule with holding steps, the sintered alloy maintained the small size of WC grains without any #eta# phase. In addition, the additional ball-milling improved the microstructure and mechanical properties of ...
Nanodimensional powders of cubic copper ferrite are synthesized by two-steps procedure of co-precipitation of copper and iron hydroxide carbonates, followed by mechanochemical treatment. X-ray powder diffraction, Moessbauer spectroscopy and temperature-programmed reduction are used for the characterization of the obtained materials. Their catalytic behavior is tested in methanol decomposition to hydrogen and CO and total oxidation of toluene. Formation of nanosized ferrite material is registered even after one hour of milling time. It is established that the prolonging of treatment procedure decreases the dispersion of the obtained product with the appearance of Fe2O3. It is demonstrated that the catalytic behavior of the samples depends not only on their initial phase composition, but on the concomitant ferrite phase transformations by the influence of the reaction medium. -- Graphical abstract: It is demonstrated that the catalytic behavior of the obtained copper ...
Focused ion beam (FIB) milling techniques are presented aiming at the manipulation of both tin dioxide (SnO_2) inverted opals and polystyrene (PS) direct opals. Different SnO_2 opals are considered in order to estimate the regularity of their bulk after the production. A SnO_2 mesoporous monolith is FIB micromachined to make it suitable for optical applications. PS direct opals are structured by FIB milling at different scales. Ordered arrays of PS opals are modified by selectively removing a single sphere. In performing this task, we discuss the effects on the FIB milling due to the gas-assisted enhanced etching and to the binding of the nearest neighbours. Techniques to achieve imaging of PS opals in absence of a conductive coating are also brought up. Furthermore, isolated PS spheres are drilled with or without enhanced etching in order to produce controlled defects on them. The FIB-assisted manipulations we show may ...
The most recently developed control technologies in a hot strip mill are described. Preview AGC has been developed with a preview control synthesis. It controls roll gaps by using the previous information of disturbances. The disturbances which are concerned are derived from the rolling force, the roll gap and the thickness of a previous stand. The thickness accuracy and the availability of mill have been improved by this technology. An on-line roll grinding (ORG) system with an on-line roll profile meter (OPM) has been developed for the purpose of achieving schedule-free rolling. The ORG smooths the worn and roughed surface of a work roll and OPM can measure the profile of a revolving roll without contact. The data obtained by the OPM are given as feedback information to the ORG. As a result, grinding accuracy has been improved and rolling restriction on width has been relaxed widely. (author)
We have researched several new focused ion beam (FIB) micro-fabrication techniques that offer control of feature shape and the ability to accurately define features onto nonplanar substrates. These FIB-based processes are considered useful for prototyping, reverse engineering, and small-lot manufacturing. Ion beam-based techniques have been developed for defining features in miniature, nonplanar substrates. We demonstrate helices in cylindrical substrates having diameters from 100 {micro}m to 3 mm. Ion beam lathe processes sputter-define 10-{micro}m wide features in cylindrical substrates and tubes. For larger substrates, we combine focused ion beam milling with ultra-precision lathe turning techniques to accurately define 25-100 {micro}m features over many meters of path length. In several cases, we combine the feature defining capability of focused ion beam bombardment with additive techniques such as evaporation, sputter deposition and electroplating in order to ...
Cu/YSZ cermet (40 and 60 vol.% Cu powder with balance YSZ) is a more economical cathode material than the conventional Ni/YSZ cermet for high temperature electrolysis (HTE) of water vapor and it was successfully fabricated by high-energy ball-milling of Cu and YSZ powders, pressing into pellets (o 13 mm x 2 mm) and subsequent sintering process at 700 deg. C under flowing 5%-H{sub 2}/Ar gas. The Cu/YSZ composite material thus fabricated was characterized using various analytical tools such as XRD, SEM, and laser diffraction and scattering method. Electrical conductivity of sintered Cu/YSZ cermet pellets thus fabricated was measured by using 4-probe technique for comparison with that of conventional Ni/YSZ cermets. The effect of composite composition on the electrical conductivity was investigated and a marked increase in electrical conductivity for copper contents greater than 40 vol.% in the composite was explained by percolation threshold. Also, Cu/YSZ cermet was ...
This work deals with a study on estimation of energy consumption in eight readily defined unit operations of cashew nut processing. Data for analysis were collected from nine cashew nut mills stratified into small, medium and large categories to represent different mechanization levels. Series of equations were developed to easily compute requirements of electricity, fuel and labour for each of the unit operations. The computation of energy use was done using spreadsheet program on Microsoft Excel. The results of application test of the equations show that the total energy intensity in the cashew nut mills varied between 0.21 and 1.161MJ/kg. Electrical energy intensity varied between 0.0052 and 0.029MJ/kg, while thermal energy intensity varied from 0.085 to 1.064MJ/kg. The two identified energy intensive operations in cashew nut processing are cashew nut drying and cashew nut roasting, altogether accounting for over 85% of the total energy ...
LiFePO{sub 4} cathode materials with distinct particle sizes were prepared by a planetary ball-milling method. The effects of particle size on the morphology, thermal stability and electrochemical performance of LiFePO{sub 4} cathode materials were investigated. The ball-milling method decreased particle size, thereby reducing the length of diffusion and improving the reversibility of the lithium ion intercalation/deintercalation. It is worth noting that the small particle sample prepared using malonic acid as a carbon source achieved a high capacity of 161 mAh g{sup -1} at a 0.1 C rate and had a very flat capacity curve during the early 50 cycles. However, the big particle samples ({proportional_to}400 nm) decayed more dramatically in capacity than the small particle size samples ({proportional_to}200 nm) at high current densities. The improvement in electrode performance was mainly due to the fine particles, the small size distribution, and ...
This regulatory guide describes methods acceptable to the NRC staff for calculating radon fluxes through earthen covers and for calculating the resulting minimum cover thickness needed to meet NRC and EPA standards. The guide also suggests methods for obtaining the various parameters used in calculating the radon fluxes and earthen cover thicknesses and suggests default values for certain parameters. This regulatory guide is applicable to active uranium tailings sites. The NRC staff is using the methods stated in this guide as a basis for review and concurrence of DOE remedial action plans for inactive sites. The guidance is intended to be used for calculating radon flux attenuation by earthen uranium mill tailings covers. The parameter values and examples presented are limited to earthen cover materials, but the diffusion theory and the methods presented are also applicable to man-made materials. Detailed supporting information for calculating minimum cover ...
This regulatory guide describes methods acceptable to the NRC staff for calculating radon fluxes through earthen covers and for calculating the resulting minimum cover thickness needed to meet NRC and EPA standards. The guide also suggests methods for obtaining the various parameters used in calculating the radon fluxes and earthen cover thicknesses and suggests default values for certain parameters. This regulatory guide is applicable to active uranium tailings sites. The NRC staff is using the methods stated in this guide as a basis for review and concurrence of DOE remedial action plans for inactive sites. The guidance is intended to be used for calculating radon flux attenuation by earthen uranium mill tailings covers. The parameter values and examples presented are limited to earthen cover materials, but the diffusion theory and the methods presented are also applicable to man-made materials. Detailed supporting information for calculating minimum cover ...
The objectives of this project were to develop technologies to manufacture self-reducing briquettes out of waste iron oxides and to recycle them in an electric arc furnace or a cupola furnace. CRM has investigated and determined the optimal characteristics (binder, size, grain size, compositions and activator for the reduction reaction) for briquettes containing mixtures of mill scales, mill sludges, electric arc furnace (EAF) dust and coal as reduction agent. The goal of obtaining briquettes, in which iron oxides are totally reduced when these briquettes are loaded with the scrap into an electric arc furnace, was achieved. Trials at ProfilARBED have shown that it is possible to recycle mill and EAF by-products conditioned in self-reducing briquettes in an electric arc furnace without influence on the performance and on the environment. The iron content of the slag does not increase as the iron of the by-product is almost ...
Anaerobic treatment of olive oil mill wastewaters (COD up to 220 kg/cubic m) is feasible, and the most promising results were obtained on UASB reactors, both at laboratory and pilot scale (tank capacity 15 litres and 5 cubic m), fed on diluted waste (COD = 13-18 kg/cubic m). Volumetric loading rates ranging from 16-21.5 kg COD/cubic m/day and 70% removal efficiencies were obtained with these digesters. Start-up of UASB reactors fed on olive oil mill waste is a delicate step which still has to be fully controlled and optimized. The best results were obtained by starting with very diluted waste (COD = 5 kg/cubic m). Granulation of the sludge, as achieved in Dutch UASB digesters fed on sugar beet wastewaters, was not obtained, but, even so, the settleability of the sludge was very good. 22 references.
A biogenic method for the treatment of uranium mill effluents containing toxic amounts of Mn"2 and "2"2"6Ra is described. The acidic tailings from the uranium mills are generally neutralised with lime and the overflow waters from tailing ponds at the discharge point, consisting of Mn"2"+ (>10 mg l"-"1) and "2"2"6Ra (> 3.0 pCi l"-"1), need further treatment before disposing off to the public utility. Arthrobacter sp. has been used for precipitating Mn"2"+ as hydrous oxide of manganes (MnO_2#centre dot#nH_2O) and along with "2"2"6Ra also gets precipitated. The effluent after bacterial treatment consisted of Mn"2"+ and "2"2"6Ra within the range of allowed concentrations as per the I.C.R.P. (International Committee of Radiological Protection) and MPC (maximum permissible concentration) standards (Mn"2"+ 95% of "2"2"6Ra could be precipitated using this method. (author). 11 refs.; 4 figs.; 4 tabs.
Specific {sup 32}P-labeled DNA probes were prepared and used to evaluate the distribution of tetracycline resistance determinants carried by gram-negative enteric bacteria isolated from pigs in 3 swine herds with different histories of antibiotic exposure. Plasmid DNA, ranging in size from 2.1 to 186 Kb, was observed in over 84% of 114 isolates studied. Two of 78 tetracycline resistant strains did not harbor plasmids. The DNA probes were isolated from plasmids pSL18, pRT29/Tn10, pBR322 and pSL106, respectively, and they represented class A, B, C and D tetracycline resistance determinants. Hybridization conditions using 0.5X SSPE at 65{degrees}C minimize cross-hybridization between the different class of tetracycline resistance genes. Cross-hybridization between class A and class C determinants could be distinguished by simultaneous comparison of the intensity of their hybridization signals. Plasmids from over 44% of the tetracycline resistant isolates did not ...
In order to achieve efficient d-lactic acid fermentation from a mixture of xylose and glucose, the xylose-assimilating xylAB operon from Lactobacillus pentosus (PXylAB) was introduced into an l-lactate dehydrogenase gene (ldhL1)-deficient Lactobacillus plantarum (?ldhL1-xpk1::tkt-?xpk2) strain in which the phosphoketolase 1 gene (xpk1) was replaced with the transketolase gene (tkt) from Lactococcus lactis, and the phosphoketolase 2 (xpk2) gene was deleted. Two copies of xylAB introduced into the genome significantly improved the xylose fermentation ability, raising it to the same level as that of ?ldhL1-xpk1::tkt-?xpk2 harboring a xylAB operon-expressing plasmid. Using the two-copy xylAB integrated strain, successful homo-d-lactic acid production was achieved from a mixture of 25?g/l xylos...
Multiplex PCR is practically a reasonable choice for molecular marker-assisted selection in potato breeding. We had developed and were using a multiplex PCR method for selection of resistance genes to cyst nematode (H1), Potato virus X (Rx1) and late blight (R1 and R2). Since then, more reliable and tightly linked markers for H1 and R2, and a new marker for resistance to Potato virus Y (Ry chc ) were developed. In this article, all these superior markers, including a positive marker to eliminate PCR-failed samples, were incorporated into one multiplex PCR assay. Using the newly developed multiplex PCR technique, five plants potentially harboring all five resistance genes were selected from 96 hybrid plants approximately 5?h after DNA extraction, which is a third of the operation time compa...
A collaboration initiated in 1989 between Judy Lachvayder and Chris Cullis in response to an application for a Christa McCauliffe Fellowship has grown into a substantial program. A one week course in biotechnology, using the Cold Spring Harbor Vector van, was run in 1990. A similar one week summer course was run by Cullis for high school freshmen and sophomores. Both programs (teachers and students) have continued with support from the Edison Biotechnology Center (EBTC), U.S. Biochemical, the Howard Hughes Medical Institute and CWRU. A core of teachers from these courses were brought together by the EBTC and the Cleveland Regional Area of Biologists (CRABS) was formed. This group holds regular meetings and develops new classroom exercises. A group of master teachers from the participants have also held their own workshops at local and national meetings. A Science and Society Symposium was held in February 1994 and an equipment loan program for teachers has been ...
The bright star 55 Cancri is known to host five planets, including a transiting super-Earth. The interferometric study presented here yields directly determined values for 55 Cnc's stellar astrophyiscal parameters: $R=0.943 \\pm 0.010 R_{\\odot}$, $T_{\\rm EFF} = 5196 \\pm 24$ K. We use isochrone fitting to determine 55 Cnc's age to be 10.2 $\\pm$ 2.5 Gyr, implying a stellar mass of $0.905 \\pm 0.015 M_{\\odot}$. Our analysis of the location and extent of the system's habitable zone (0.67--1.32 AU) shows that planet f ($M \\sin i = 0.155 M_{Jupiter}$) spends the majority of the duration of its elliptical orbit in the circumstellar habitable zone, where, with moderate greenhouse heating, it could harbor liquid water. Finally, our direct value for 55 Cancri's stellar radius allows for a model-independent calculation of the physical diameter of the transiting super-Earth 55 Cnc e ($\\sim 2.05 \\pm 0.15 R_{\\earth}$), which, depending on the planetary mass assumed, ...
A full scale co-digestion system for sludge and Olive oil mill effluent (OME) and a regional sludge management plan has been set-up to solve urgent environmental problems, modifying an existing cold municipal digester, by means of simple and effective technology. Monitoring of the full scale system demonstrated good compatibility between OME and sludge, up to 20% mixture, and high removal of organics compounds. Coagulant compounds present in OME (mainly Fats), promoted aggregation and settling of anaerobic sludge and also its acetoclastic activity, minimizing the load returned to the wastewater treatment line and improving also the activated sludge system. The co-digestion of OME with sludge agreed the project purposes, and produced large quantity of biogas and electric energy.
Ford, Bacon, Davis Utah Inc. has reevaluated the Spook site in order to revise the December 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings 48 mi northeast of Casper, in Converse County, Wyoming. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 187,000 tons of tailings at the Spook site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors.
To study the effect of CuO on the electrochemical properties of MgNi alloy, the MgNi-xCuO (x = 3, 5 and 10 wt%) composites were prepared by ball-milling method. The X-ray diffraction (XRD) analysis showed that the structures of the composites were amorphous. The cycle stability of the composites was improved compared to pure MgNi alloy due to the enhancement of the anti-corrosion property in the alkaline electrolyte, and the composite with 5 wt% CuO ball-milled for 15 h exhibited the best performance. Electrochemical impedance spectroscopy (EIS) and potential-step measurements indicated that the electrochemical kinetics of the composites was improved.
In this paper, research on pass schedule of tandem cold mill (TCM) is carried out. According to load (reduction, rolling force, motor power) balance, non-linear equations set with variables of inter-stand thickness is constructed. The pass schedule optimization is carried out by solving the non-linear equations set. As the traditional method, the Newton-Raphson method is used for solving the non-linear equations set. In this paper a new simple method is brought up. On basis of the monotone relations between thickness and load, the inter-stands thickness is adjusted dynamically. The solution of non-linear equations set can be converged by iterative calculation. This method can avoid the derivative calculation used by traditional method. So, this method is simple and calculation speed is high. It is suitable for on-line control. (author)
In this paper, research on pass schedule of tandem cold mill (TCM) is carried out. According to load (reduction, rolling force, motor power) balance, non-linear equations set with variables of inter-stand thickness is constructed. The pass schedule optimization is carried out by solving the non-linear equations set. As the traditional method, the Newton-Raphson method is used for solving the non-linear equations set. In this paper a new simple method is brought up. On basis of the monotone relations between thickness and load, the inter-stands thickness is adjusted dynamically. The solution of non-linear equations set can be converged by iterative calculation. This method can avoid the derivative calculation used by traditional method. So, this method is simple and calculation speed is high. It is suitable for on-line control. (author)
A kinetic study of the degradation by ozone of eight phenolic acids present in wastewaters from olive oil mills has been performed by using a competition kinetic method. The selected phenolic acids are: caffeic, p-coumaric, syringic, vanillic, 3,4,5-trimethoxybenzoic, veratric, p-hydroxy-benzoic, and protocatechuic. The influence of the operating variables (temperature, pH, and ozone partial pressure in the gas stream) is established, and the stoichiometric ratios for the individual direct reactions between ozone and each acid are determined. Once the reaction rate constants are evaluated, they are correlated as a function of temperature and pH into kinetic expressions which are provided for every phenolic acid. The global process occurs in the fast and pseudo-first-order kinetic regime of absorption, a condition required by the competition model to be used.
Nomographs that calculate the threshold values of surface fire parameters which lead to crown fire initiation were created by linking two separate fire behavior models: Van Wagner?s crown fire ignition criteria and Byram?s surface fire model. The nomographs were also based on the existing surface (fuel load, fuel heat content) and canopy (foliar moisture content, live crown base height) fuel models of Aleppo (Pinus halepensis Mill.) pine forests of Mediterranean Greece. The most important fire parameters for crown fire initiation that are calculated by the nomographs are the critical flame length and the forward spread rate of the surface fire. These parameters are readily observable in the field during fires. The nomographs provide a judicious way to assess whether a crown fire is likely ...
In this work, we report for the first time on the analysis of genetic diversity within a set of 36 Tunisian Opuntia ficus indica (L.) Mill. ecotypes using RAPD markers.Random decamer primers were screened to assess their ability to detect polymorphisms in this plant crop. Thirty-nine RAPD markers were revealed and used to survey the genetic diversity at the DNA level and to establish relationships.Consequently, considerable genetic diversity was detected and the UPGMA analysis permitted the discrimination of all the genotypes and enabled their sorting into thirteen groups. The accession `R Sbiba inerme' was significantly divergent from all tested genotypes. In addition, as shown by the clustering the tested genotypes did not significantly diverge, though originating from different localiti...
Modeling is performed for focused-ion-beam (FIB) sputtering and redeposition on trench sidewalls in a steady state approximation. Calculations are carried out to demonstrate the sputtered surface profile under known parameters such as sputtering yield as a function of ion incident angle, the FIB current density profile, and the FIB scan speed. It is found that a steplike slope with a gradient angle of {theta}{sub 0} is formed at the FIB bombarding position. Furthermore, the redeposition flux on the sidewalls is calculated as a function of {theta}{sub 0} for the FIB trench milling assuming the cosine law for the angular distribution of the sputtered atom. The redeposition will be more accurately predictable and controllable when more information about these assumptions is obtained.
Modeling is performed for focused-ion-beam (FIB) sputtering and redeposition on trench sidewalls in a steady state approximation. Calculations are carried out to demonstrate the sputtered surface profile under known parameters such as sputtering yield as a function of ion incident angle, the FIB current density profile, and the FIB scan speed. It is found that a steplike slope with a gradient angle of #theta#_0 is formed at the FIB bombarding position. Furthermore, the redeposition flux on the sidewalls is calculated as a function of #theta#_0 for the FIB trench milling assuming the cosine law for the angular distribution of the sputtered atom. The redeposition will be more accurately predictable and controllable when more information about these assumptions is obtained.
Mechanical alloying is an important pre-requisite for the manufacturing of heat resistant oxide-dispersion-strengthened superalloys. Though the microstructure of these materials after hot extrusion and recrystallization treatment is well documented, little is known about the microstructural evolution during ball-milling. A method was tested to prepare electron transparent foils and extraction replica from powder particles for TEM investigations. The microstructure was found to consist of a Ni-Cr-Al solid solution in which submicron particles of refractory metals were embedded. The extremely fine grainize of about 50 nm is the consequence of severe plastic deformation. Yttria particles could not be detected in the powder after ball milling, but after a heat treatment at 1000 C the well-known fine dispersion of oxide particles was evident. (orig.)
A concentric reducer tube, which was a part of the top exit roughing hydraulic descaler in a hot strip mill failed prematurely under working pressure. A detailed metallurgical investigation comprising physical examination, optical microscopy, scanning electron microscopy, and electron probe microanalysis was carried out to find out the genesis of the failure. Physical examination revealed cracks located symmetrically around the circumference of the tube that ran along its full length, up to the weld beads at both ends. Optical microscopy of etched samples revealed a banded ferrite-pearlite structure and the existence of forging folds near the change-in-section(160? fillets). Cracks were found to initiate from these forging folds. No structural abnormalities were found in the weld beads and...
Nd{sub 40}Fe{sub 30}Al{sub 10}Co{sub 15}B{sub 5} alloys were fabricated by high energy ball milling method under various conditions. Microstructure of the alloys was investigated by X-ray diffraction and electron microscopy techniques. Magnetic properties were characterized by hysteresis and thermomagnetic measurements. The high coercive fields up to 2.36 T have been observed on the samples consisting of Nd{sub 2}(Fe,Co,Al){sub 14}B, Nd{sub 6}(Fe,Co,Al){sub 14} and Nd crystallites imbedded in a residual amorphous matrix.
A focused ion beam (FIB) is used to accurately sculpt predetermined micron-scale, curved shapes in a number of solids. Using a digitally scanned ion beam system, various features are sputtered including hemispheres and sine waves having dimensions from 1-50 {micro}m. Ion sculpting is accomplished by changing pixel dwell time within individual boustrophedonic scans. The pixel dwell times used to sculpt a given shape are determined prior to milling and account for the material-specific, angle-dependent sputter yield, Y({theta}), as well as the amount of beam overlap in adjacent pixels. A number of target materials, including C, Au and Si, are accurately sculpted using this method. For several target materials, the curved feature shape closely matches the intended shape with milled feature depths within 5% of intended values.
There is currently great interest in combining focused ion beam (FIB) and scanning electron microscopy technologies for advanced studies of polymeric materials and biological microstructures, as well as for sophisticated nanoscale fabrication and prototyping. Irradiation of electrically insulating materials with a positive ion beam in high vacuum can lead to the accumulation of charge, causing deflection of the ion beam. The resultant image drift has significant consequences upon the accuracy and quality of FIB milling, imaging and chemical vapour deposition. A method is described for suppressing ion beam drift using a defocused, low-energy primary electron beam, leading to the derivation of a mathematical expression to correlate the ion and electron beam energies and currents with other parameters required for electrically stabilizing these challenging materials.
The US NRC, in its Generic Environmental Impact Statement on uranium milling has specified that the radon flux escaping a uranium mill tailings pile will be reduced to pCi/m/sup 2/ s by application of covering layers of soils and clays. These covers present a radon diffusion barrier, which sufficiently increases the time required for radon passage from the tailings to the atmosphere to allow for decay of /sup 222/Rn within the cover. The depth of cover necessary to reduce the escaping radon flux to the prescribed level is to be determined by calculation, and requires precise knowledge of the radon diffusion coefficient in the covering media. A Radon Attenuation Test Facility was developed to determine rates of radon diffusion through candidate cover materials. This paper describes this facility and its application for determining the influence of physical properties of the soil column on the radon diffusion coefficient.
Ford, Bacon and Davis Utah Inc. has reevaluated the Tuba City site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Tuba City, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 0.8 million tons of tailings at the Tuba City site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors.
Ultrafine particles of Co-P were synthesized by direct ball milling of Co and P powders and also investigated as a reversible hydrogen storage electrode material. The electrochemical results demonstrated that the reversible charge-discharge capacity of the Co-P electrode can reach more than 300mAh/g. In addition, the cycling ability and high rate capability of the Co-P electrode are excellent with only 5% capacity decay after 100 cycles at a high rate of 300mA/g. The temperature-programmed desorption measurements (TPD) of the Co-P electrode revealed that the charge and discharge reactions of the Co-P electrode proceeds predominantly through electrochemical hydrogen storage mechanism and the electrooxidation of cobalt contributes only a negligible part to the reversible electrochemical capacity. (author)
Rice husk generated as a by-product of rice processing is an important energy resource. The availability of this resource in India has been assessed and the technologies for exploitation of its energy potential in rice processing industry discussed. Nomographs have been developed for estimation of the husk required to meet the energy demand of parboiling, drying and milling operations. The unit cost of electricity using rice husk gasifier-based power generation systems has been calculated and its financial feasibility assessed in comparison with utility-supplied and diesel-generated electricity. With the cost and efficiency data assumed here, the unit cost of electricity produced by rice husk gasifier-dual fuel engine-generator system varies between Rs 2/kWh and Rs 7/kWh. (author)
Rice husk generated as a by-product of rice processing is an important energy resource. The availability of this resource in India has been assessed and the technologies for exploitation of its energy potential in the rice processing industry discussed. Nomographs have been developed for estimation of the husk required to meet the energy of parboiling, drying and milling operations. The unit cost of electricity using rice husk gasifier-based power generation systems has been calculated and its financial feasibility assessed in comparison with utility-supplied and diesel-generated electricity. With the cost and efficiency data assumed here, the unit cost of electricity produced by rice husk gasifier-dual fuel engine-generator system varies between Rs 2/kWh and Rs 7/kWh. (35 Rs approximates to SUS 1.). (author)
Effect of alcohol solvent in mixing process on process on the microstructure and sintering behavior of ceramic-based composites was inestigated in detail. The mixture of fine ceramic powders was prepared through the conventional ball-milling method with various alcohol media. The particle distributions of fine ceramic powders were strongly dependent on the kind of alcohol employed during ball-milling. Ceramic-based composites were fabricated by hot-pressing the mixture of fine ceramic powders. Their microstructures and some mechanical properties of the ceramic-based composites were evaluated. It was found that the viscosity of alcohol, surface tension and contat angle greatly affect the sinterbility and some of the mechanical properties of ceramic-based somposites. (author)
Starting from the generalized Konishi anomaly equations at the non-perturbative level, we demonstrate that the algebraic consistency of the quantum chiral ring of the N=1 super Yang-Mills theory with gauge group U(N), one adjoint chiral superfield X and N_f<=2N flavours of quarks implies that the periods of the meromorphic one-form Tr dz/(z-X) must be quantized. This shows in particular that identities in the open string description of the theory, that follow from the fact that gauge invariant observables are expressed in terms of gauge variant building blocks, are mapped onto non-trivial dynamical equations in the closed string description.
The high-nickel austenitic alloy 800 (in both the mill-annealed and the solution-treated grades) has several attractive properties that make it a good candidate for service attractive properties that make it a good candidate for service at elevated temperatures in corrosive environments. One such property is creep resistance. This report analyzes the elevated-temperature creep behavior of the mill-annealed grade, generally referred to simply as alloy 800. (The solution-treated grade is known as alloy 800H). Available data over the temperature range from 538 to 760/sup 0/C were collected and evaluated to yield mathematically approximations for creep-rupture and strain-time behavior for use in design calculations. However, the creep behavior of this material is extremely complex, and the analysis presented here contains substantial uncertainties. All results in this report should be considered preliminary because of limited data currently ...
This paper evaluates the performance of asphalt membranes by examining the chemical and permeability changes experienced by the asphalt during aging tests. The aging process was accelerated by exposing the asphalt to elevated temperatures, high oxygen concentrations, and increased strengths of aqueous oxidizing agents. The synergistic effects of the variables are evaluated by using a fractional factorial experimental design. The installation costs for a catalytically airblown asphalt liner are roughly half that of the typical polymeric materials, and also less than the rubberized asphalt membrane. The results of the initial accelerated aging tests of the asphalt membranes indicate that this material will provide stable, long-term leachate isolation in a mill tailings environment.
In this study, wood samples were exposed to light irradiations (direct sunlight, xenon lamp, mercury vapour lamp) and thermal treatments were carried out in dry- and in humid conditions at 90degreeC. One part of the samples was covered by an aluminium plate during light irradiation. The samples under the aluminium plate also suffered considerable chemical changes, monitored by infrared technique and colour measurement. The sunlight produced greater colour change under the aluminium plate than the artificial light sources. During light irradiation, the carbonyl band having two maximum at 1700 and 1746cm-1 increased and the peak of the aromatic skeletal vibration arising from lignin (1510cm-1) decreased together with the guaiacyl vibrations at 1275cm-1. There was absorption decrease at 1174c...
In this article, we studied the effects of variable viscosity and thermal conductivity on an unsteady two-dimensional laminar flow of a viscous incompressible conducting fluid past a semi-infinite vertical porous moving plate taking into account the effect of a magnetic field in the presence of variable suction. The fluid viscosity is assumed to vary as an inverse linear function of temperature but the thermal conductivity is assumed to vary as a linear function of temperature. It is assumed that the porous plate moves with a constant velocity in the direction of fluid flow, and the free stream velocity follows the exponentially increasing small perturbation law. The governing equations for the flow are transformed into a system of nonlinear ordinary differential equations by perturbation ...
New cassettes for 201 mm{times}252 mm (8{double_prime}{times}10{double_prime}) and 201 mm{times}400 mm (8{double_prime}{times}15.75{double_prime}) storage phosphor plates have been developed at the Synchrotron Resource of the Howard Hughes Medical Institute. The purpose for this work was mainly twofold. Firstly, to diminish the number of manual operations when putting the storage phosphor plate into the cassette or when extracting it from the cassette. Secondly, to render such a cassette much lighter than the former metal cassette previously in use. These two goals were achieved by making new cassettes that are operated as one piece instead of two or three independent parts as with the former systems. The cassettes have been extensively tested and found to be very useful.
The impacted armor targets used in testing high density armor-piercing ammunition containing depleted uranium (DU) are subject to disposal as low-level radioactive waste. Because of the costs associated with disposal of the entire armor plate and the limited use of secured commercial sites in the future, the U.S. Army is seeking to identify and evaluate new technologies for decontaminating these armor plates. The objectives of this Phase I SBIR program are two-fold, namely: to develop a selective solvent that can decontaminate impacted armor targets containing DU for disposal or recycle, and to identify and characterize technologies that can remove depleted uranium from the solvent for solvent recycle and uranium recovery for easier hazardous-waste disposal.
A novel system for real-time radiation monitoring in reactor or accelerator facilities has been studied using an imaging plate. The authors made a feasibility study on a new neutron detection system using both photostimulated luminescence (PSL) and prompt luminescence (PL) generated in a neutron imaging plate (NIP) when the NIP is irradiated by neutrons. A readout system consisting of a semiconductor laser and a photomultiplier tube was fabricated for the purpose. It was confirmed that the system can measure both PSL and PL, where Am-Li was used as a neutron source. It may be possible to establish a new wide-range neutron monitoring system using the developed system as a PL mode normally, and as a PSL mode in case of intense neutron dose that cannot be measured in a PL mode because of saturation of the detection system. (author)
A novel system for real-time radiation monitoring in reactor or accelerator facilities has been studied using an imaging plate. The authors made a feasibility study on a new neutron detection system using both photostimulated luminescence (PSL) and prompt luminescence (PL) generated in a neutron imaging plate (NIP) when the NIP is irradiated by neutrons. A readout system consisting of a semiconductor laser and a photomultiplier tube was fabricated for the purpose. It was confirmed that the system can measure both PSL and PL, where Am-Li was used as a neutron source. It may be possible to establish a new wide-range neutron monitoring system using the developed system as a PL mode normally, and as a PSL mode in case of intense neutron dose that cannot be measured in a PL mode because of saturation of the detection system. (author)
Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni-Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitride (CrN and Cr2N) surface layer through nitridation of Fe-base stainless steel alloys. The key to form a protective Cr...
The following method is proposed as a supplement to main patent 2419107, which deals with the filling of tubular plates surrounding the lead cores: the flat materials which are used to produce the jacket tubes are prepared before forming into jacket tubes by a film producing aqueous carboxy-methyl cellulose solution closing the pores. The preparation can be done by coating the flat material with a soluble foil. After pressing the paste in, the tubular plates are dried and after cooling are dipped into sulphuric acid with a specific gravity of 1.24 g/cm/sup 3/. The carboxy-methyl cellulose is dissolved and the permeability of the tube walls for electrolyte is restored after only 15 minutes.
A kind of metastable beta titanium alloy, i.e. Ti-10Mo-8V-1Fe-3.5Al, was aged under elastic compressive stress. Transmission electron microscopy (TEM) investigations revealed that, in the stress-aged samples, precipitated alpha plates were parallel to each other. However, in the conventionally aged samples, alpha plates intersected each other. In other words, variant of alpha plate was selected in the stress-aged samples. Tensile tests showed that, at equivalent tensile strength, the stress-aged samples exhibited higher ductility, compared to the conventionally aged ones.
An analysis is presented for the effects of chemical reaction and thermal radiation on hydromagnetic free convection heat and mass transfer for a micropolar fluid via a porous medium bounded by a semi-infinite vertical porous plate in the presence of heat generation. The plate moves with a constant velocity in the longitudinal direction and the free stream velocity follows an exponentially small perturbation law. A uniform magnetic field acts perpendicularly to the porous surface in which absorbs the micropolar fluid with a suction velocity varying with time. Analytical expressions are computed numerically. Numerical calculations are carried out the purpose of the discussion of the results which are shown on graphs and the effects of the various dimensionless parameters entering into the p...
Nitridation of Cr-bearing alloys can yield low interfacial contact resistance (ICR), electrically conductive and corrosion-resistant CrN or Cr2N base surfaces of interest for a range of electrochemical devices, including fuel cells, batteries, and sensors. This paper presents results of exploratory studies of the nitridation of commercially available, high Cr (30-35wt%) Ni-Cr alloys and a ferritic high Cr (29wt%) stainless steel for proton exchange membrane fuel cell (PEMFC) bipolar plates. A high degree of corrosion resistance in sulfuric acid solutions designed to simulate bipolar plate conditions and low ICR values were achieved. Oxygen impurities in the nitriding environment were observed to play a significant role in the nitrided surface structures that formed, with detrimental effect...
A procedure based on electrophoretic deposition (EPD) was developed to coat metal plates with powder catalysts. The method was tested on stainless-steel plates with three Ni-based catalysts for the steam reforming of ethanol. The catalysts (Ni/La2O3/g-Al2O3) contained 15% Ni and 8% La, and were prepared using three types of g-alumina with different textural properties. The powder catalysts were suspended in isopropanol, and EPD deposition was performed with a voltage of 100V and a distance between electrodes of 2cm. Deposition time was varied between 3 and 7min, which gave a thickness of the catalyst layer from around 30 to 100mm. The morphology of the catalyst layer was dependent on the textural characteristics of the g-Al2O3 used to prepare the catalyst. The activity of the catalyst plat...
The combined process of low temperature plasma nitriding and TiN film deposition was realized on the plasma-assisted vacuum arc plating set. The process of plasma nitriding can be done below 200 degree C. The low temperature plasma nitriding and TiN film deposition was realized on the same device. By the SEM analysis of the plating structure, low hardness grads from the substrate to the film was obtained, and it was found that the mixed nitride plating formed at the interface between the substrate and the film. The quantitative measurement of substrate-film adherence showed that the adherence was improved notably by using the process. The adherence between film and substrate can reach to 59.6 MPa without the bias voltage supplying
The fully developed electrically conducting micropolar fluid flow and heat transfer along a semi-infinite vertical porous moving plate is studied including the effect of viscous heating and in the presence of a magnetic field applied transversely to the direction of the flow. The Darcy-Brinkman-Forchheimer model which includes the effects of boundary and inertia forces is employed. The differential equations governing the problem have been transformed by a similarity transformation into a system of non-dimensional differential equations which are solved numerically by element free Galerkin method. Profiles for velocity, microrotation and temperature are presented for a wide range of plate velocity, viscosity ratio, Darcy number, Forchhimer number, magnetic field parameter, heat absorption ...
This paper presents extensive non-linear finite element (FE) analysis and formulation development work carried out on the ultimate compressive strength of plates and stiffened panels of ship structures. A review of contemporary designs for large ships was carried out. The existing formulae for plate ultimate compressive strength were reviewed and compared with non-linear FE analysis results. A semi-analytical formula for ultimate compressive strength assessments of stiffened panels was proposed and is described. The developed formula was verified against results using ABAQUS non-linear FE software for a series of 61 stiffened panels and a good agreement between the proposed formula and FE results were achieved. The method was verified against a large number of published FE results and was ...
Purpose - This study seeks to explore the aerodynamic performance of wings with different shapes at low Reynolds numbers. Design/methodology/approach - The airfoils of these wings are made from aluminum plates, and the maximum cord length and wingspan are 15?cm. Wings A to D are plates with 6 percent Gottingen camber but different wing planforms. The forward-half sections of wings E and F are dragonfly-like, whereas the rear-half sections of wings E and F are flat and positively cambered, respectively. The aspect ratios of these wings are close to one, and the ratios of plate thickness to the maximum cord length are 1.3 percent. Experimental results indicate that the wings with Gottingen camber have a superior lift and lift-to-drag ratio, whereas the wings with dragonfly-like airfoils perf...
Volume one contains calculations for: embankment design--embankment material properties; Union Carbide site--bedrock contours; vicinity properties--origin of contamination; North Continent and Union Carbide sites contaminated materials--excavation quantities; and demolition debris--quantity estimate.
Volume four contains calculations for: Borrow areas--site evaluation; temporary facilities--material quantities; embankment quantities--excavation and cover materials; Burro Canyon site excavation quantities--rippable and unrippable materials; site restoration--earthwork quantities and seeding; and bid schedule quantities and material balance.
... Although the rest of the country is less affected, if UK annual feeding and milling volumes of wheat are approximately 120,000t the drought will inevitably result in a shortfall. Looking back at the 2010 season the organic arable market performed strongly, with average feed wheat values since Christmas of 𧷐/tonne - 䀆/t higher then the same period last year. This provided a profitable ...
Soil placed over any sealant/barrier system can provide a protective mantle if the soil is not lost by erosion. Vegetation is an attractive choice for controlling erosion because it can provide an economical self-renewing cover that serves to reduce erosion by both wind and water. The objective of this research and development effort is to select and test vegetation strategies, including the choice of species and methods for revegetation that are compatible with sealant/barrier systems and are suited to soils and climates at inactive uranium mill tailings sites.
The Maybell uranium mill tailings site is 25 miles (mi) (40 kilometers [km]) west of the town of Craig, Colorado, in Moffat County, in the northwestern part of the state. The unincorporated town of Maybell is 5 road mi (8 km) southwest of the site. The site is 2.5 mi (4 km) northeast of the Yampa River on relatively flat terrain broken by low, flat-topped mesas. U.S. Highway 40 runs east-west 2 mi (3.2 km) south of the site. The designated site covers approximately 110 acres (ac) (45 hectares [ha]) and consists of a concave-shaped tailings pile and rubble from the demolition of the mill buildings buried in the former mill area. The site is situated between Johnson Wash to the east and Rob Pit Mine to the west. Numerous reclaimed and unreclaimed mines are in the immediate vicinity. Aerial photographs (included at the end of this executive summary) show evidence of mining activity around the Maybell site. Contaminated ...
This volume contains appendices D6 through D8 containing laboratory test data: from MK-F investigation, 1987, Old Rifle and New Rifle sites; on bentonite amended radon barrier material; and from MK-F investigation, 1987, riprap tests.
Reflective diffraction grating. A focused ion beam (FIB) micromilling apparatus is used to store color images in a durable medium by milling away portions of the surface of the medium to produce a reflective diffraction grating with blazed pits. The images are retrieved by exposing the surface of the grating to polychromatic light from a particular incident bearing and observing the light reflected by the surface from specified reception bearing.
It has been shown that mechanical milling of iron in water results in formation of nanocrystalline magnetite Fe3O4 with an average particle size of 0.6 ?m, saturation magnetization of 77 Am2/kg and coercivity of ?150 A/cm. Along with magnetite, an antiferromagnetic Fe-O phase (?10 wt%), which is an aggregate of small iron-oxygen clusters forms.
...org/ (1 vote) defends the native forest ecosystems and communities of the Southeast United States which are threatened by industrial scale clearcutting to feed chip mills Added: Jan. 20, 2001 | Rate It Don't Buy SFI http://www.dontbuysfi.com/home/ (2 votes) campaign to show the \\
The continuous bioprocessing of simulated steam-stripped sulfite pulp mill evaporator condensates using Candida utilis to produce single cell protein has been studied. At 32 degrees C, processing can be conducted at space velocities of up to 0.43 hr/sup -1/ with over 90% removal of acetic acid present at an initial concentration of 2 g/liter. (Refs. 16).
This study analyzes the economic impact that could result from the application of effluent standards and limitations issued under Sections 301, 304, 306, 307 of the Clean Water Act to the pulp, paper, and paperboard industry, including builders' paper and roofing felt manufacturing.
The engineering and economic feasibility of using the geothermal resources in East Mesa, California, in a new corn processing plant is evaluated. Institutional barriers were also identified and evaluated. Several alternative plant designs which used geothermal energy were developed. A capital cost estimate and rate of return type of economic analysis were performed to evaluate each alternative. (MHR)
We examined a catalytic effect of niobium oxide (Nb{sub 2}O{sub 5}) on the hydrogen storage properties of MgH{sub 2} prepared by mechanical ball milling method. The MgH{sub 2} composite doped with 1 mol% Nb{sub 2}O{sub 5} by ball milling for 20 h desorbed hydrogen up to {approx}6 mass% in the temperature range from 200 to 250 {sup o}C at the heating rate of 5 {sup o}C/min under a purified helium flow. After dehydrogenation at 200 {sup o}C, the product showed remarkable hydrogen absorption kinetics. A large amount of gaseous hydrogen up to {approx}4.5 mass% was absorbed even at room temperature under 1 MPa hydrogen pressure within 15 s and finally its capacity reached up to 5 mass%. Furthermore, the valence state of Nb{sub 2}O{sub 5} doped in MgH{sub 2} was examined by X-ray absorption near edge structure (XANES) measurement. The results indicated that additive Nb{sub 2}O{sub 5} was reduced by MgH{sub 2} during mechanical ...
Total and net energies used harvesting 30-cm billets at 8 t/h were 1 and 0.3 kW x h/t, respectively. Harvested crop had 4% leaves, a 70% mass fraction of billets 30-40 cm long, and a 49/sup 0/ angle of repose. A self-unloading forage wagon with beaters and controls metered billets at 1.5 t/h to feed a juice-expression mill.
This paper reports the results of a fine-probe EDS microanalytical study of cellular precipitation in a Cu-Ti binary alloy. Compositional profiles across the solute depleted Cu-rich FCC lamellae and the Cu_4Ti lamellae within isothermally formed cellular colonies were measured in a FEG-TEM from thin-foil specimens prepared by conventional electropolishing and by a technique using a Ga"+ focused ion-beam (FIB). The Cliff-Lorimer ratio method, with an absorption correction, was employed to quantify the compositions. Two FIB samples were prepared with different orientations of the lamellae with respect to the ion-milling direction. The compositional profiles across the Cu-rich FCC lamellae and the Cu_4Ti compound lamellae in both the FIB-prepared samples and the electropolished sample were, within experimental error, numerically equivalent. The composition of the Cu_4Ti compound phase lamellae was very close to the ideal stoichiometric composition of 20 at% Ti. It is ...
Using the manifestly causal gluon propagator in the light-cone gauge, we evaluate two one-loop Feynman integrals which appear in the computation of the three-gluon vertex correction in the two-component formalism of the Yang-Mills gauge fields. We conclude that they both are finite for {omega} -> 2, where {omega} is the dimensional regulator. They belong to a class of finite one-loop light-cone integrals. (author). 7 refs.
The present study has examined for #alpha#/#beta#-Ti alloys the relationship between the morphology and crystallography of Widmanstaetten plates of #alpha#-Ti in colonies within a prior grain of #beta#-Ti. Thus, optical metallography, scanning electron microscopy and transmission electron microscopy have been used to characterize the morphological features of the microstructure, whereas orientation-imaging microscopy (OM) and transmission electron microscopy (TEM) have been employed to reveal crystallographic information. It has been discovered that within a prior #beta#-Ti grain, although the growth direction of the Widmanstaetten plates in given colonies may differ by large angles from #alpha#-plates in other colonies, they may exhibit very close crystallographic relationships. For example, inclined #alpha#-plates may share common basal planes and be related by a rotation of #approx#10.5 deg. about ...
Jun 10, 2011 ... Subsonic flow past a semi-infinite flat plate is modeled at Reynolds number 6 ..... data is taken from Cook, McDonald, and Firmin, AGARD-AR-138, 1979, p. ...... too large a time-averaged separation bubble behind the hump. ...
When chest radiographs are obtained using an anti-scatter grid in a mobile x-ray unit by Fuji Computed Radiography (FCR), right lung densities may differ from left lung densities owing to misalignment caused by an oblique x-ray beam. Such misalignment is considered to be caused by factors such as the shape of the bed and angle of the x-ray tube. Misalignment is especially frequent when exposure is carried out in the sitting position. Although a low-ratio grid has been reported to offer improvement, the misalignment is not completely eliminated. Therefore, we used a copper plate without a lattice feature instead of grid, and examined the results. The copper plate was found to have the ability of a grid to eliminate radiation scatter, and, furthermore, to offer the physical capabilities of a grid as determined by Carlin's new grid assessment method. Image quality was demonstrated through contrast manipulation to be equal to that obtained ...
When chest radiographs are obtained using an anti-scatter grid in a mobile x-ray unit by Fuji Computed Radiography (FCR), right lung densities may differ from left lung densities owing to misalignment caused by an oblique x-ray beam. Such misalignment is considered to be caused by factors such as the shape of the bed and angle of the x-ray tube. Misalignment is especially frequent when exposure is carried out in the sitting position. Although a low-ratio grid has been reported to offer improvement, the misalignment is not completely eliminated. Therefore, we used a copper plate without a lattice feature instead of grid, and examined the results. The copper plate was found to have the ability of a grid to eliminate radiation scatter, and, furthermore, to offer the physical capabilities of a grid as determined by Carlin's new grid assessment method. Image quality was demonstrated through contrast manipulation to be equal to that obtained by grid ...
Cryogenic distillation is the main industrial method for separating hydrogen's isotopes, because it presents the advantage of high separating factors and also the possibility of processing great quantities of gases. In the case of multicomponent mixtures the determination of transport for molecular species between the two phases is very difficult owing to the particularities of physical characteristics of each component from the mixture. The transport of molecular species is also strongly influenced by the hydrodynamics of two phases, in strong connection with the dimension of the interface between the vapor and liquid phase. The characteristics of the interface depend on the type and geometry of the separation area: plates or package. The traditional methods of analysis for exchange processes use the concept 'theoretic plate', a physical entity for which the values of concentrations for vapors and liquid that leaves ...
BackgroundMedian sternotomy infection and bony nonunion are two commonly described complications which occur in 0.4 - 5.1% of cardiac procedures. Although relatively infrequent,...Full Text Available
1. Miniature end-plate potentials (m.e.p.p.s) were intra- and extracellularly recorded from neuromuscular junctions in rat phrenic nerve—diaphragm preparations in vitro....Full Text Available
BackgroundSymptomatic heterotopic ossification (HO) in multiple trauma patients may lead to follow up surgery, furthermore the long-term outcome can be restricted. Knowledge of the...Full Text Available
Randomly amplified polymorphic DNA (RAPD) analysis and the PCR assay were used in combination with dilution plating on a semiselective medium to detect and enumerate propagules of Trichoderma...Full Text Available
Coded imaging techniques using thick, micro-Fresnel zone plates as coded apertures have been used to image x-ray emissions (2-20 keV) and 3.5 MeV Alpha particle emissions from laser driven micro-implosions. Image resolution in these experiments was 3-8 ..mu..m. Extension of this coded imaging capability to higher energy x-rays (approx. 100 keV) and more penetrating charged particles (e.g. approx. 15 MeV protons) requires the fabrication of very thick (50-200 ..mu..m), high aspect ratio (10:1), gold Fresnel zone plates with narrow linewidths (5-25 ..mu..m) for use as coded aperatures. A reactive ion etch technique in oxygen has been used to produce thick zone plate patterns in polymer films. The polymer patterns serve as electroplating molds for the subsequent fabrication of the free-standing gold zone plate structures.
Coded imaging techniques using thick, micro-Fresnel zone plates as coded apertures have been used to image x-ray emission (2--20 keV) and 3.5 MeV Alpha particle emissions from laser driven micro-implosions. Image resolution in these experiments was 3--8 ..mu..m. Extension of this coded imaging capability to higher energy x rays (approx.100 KeV) and more penetrating charged particles (e.g., approx.15 MeV protons) requires the fabrication of very thick (50--200 ..mu..m), high aspect ratio (10:1), gold Fresnel zone plates with narrow linewidths (5--25 ..mu..m) for use as coded apertures. A reactive ion etch technique in oxygen has been used to produce thick zone plate patterns in polymer films. The polymer patterns serve as electroplating molds for the subsequent fabrication of the free-standing gold zone plate structures.
A Staphylococcus strain was inoculated on the top and cut surfaces of freshly baked Southern custard pies which were then packaged in a pasteboard carton and held at 30 C. Daily plate...Full Text Available
Since April, 1985, we have, in co-operation with the Fuji Film Co., Ltd., used Fuji Computed Radiography (FCR) in the diagnosis of spinal disorders. FCR is a new computed radiographic system which uses an energy-storage phosphorus panel called an ''Imaging Plate'' as an image sensor. The ''Imaging Plate'' can be used to obtain radiographs in exactly the same way as the screen-film combination used in conventional radiography; X-rays are exposed on the ''Imaging Plate'' instead of X-ray film in the conventional fashion, and then the ''Imaging Plate'' is calculated. The processed digital data from the scans is transformed into a picture by means of digital-to-analogue conversion. The pictures are always clear and beautiful. Plain films of the spine taken by FCR are even clearer, even in the cervicothoracic region, where it is usually difficult to obtain clear cervicothoracic films in conventional ...
A device for reducing the muzzle blast and flash from large caliber guns is disclosed. A container having a plurality of internal chambers and baffle plates filled with an aqueous foam is mounted to the muzzle of the gun barrel. The foam and chambers co-o...
On agar plates, daughter cells of Escherichia coli mutually slide and align side-by-side in parallel during the first round of binary fission. This phenomenon has been previously attributed...Full Text Available
Three major series of experiments have been conducted with the FELIX facility at ANL. Experiments on the coupling between eddy currents and angular displacements of loops and plates in crossed constant and changing magnetic fields demonstrated that the co...
A test methodology for measuring temperature, impedance, pH, and electrochemical potential distributions within a sludge-packed tube support plate crevice in a laboratory test is described. The method successfully showed that there were large concentration gradients between the tube and tube support plate sides of the crevice. The testing also showed that strong bases concentrated more effectively than strong acids, and that the crevice pH, when exposed to seawater-based solutions, increased with increasing superheat and decreasing bulk concentration. The large variations in the crevice chemistry observed under heat transfer were eliminated upon shutdown. These new test data suggest that it might be beneficial to evaluate the variation in the extent of stress corrosion cracking with tube support plate elevation found in some steam generators in light of local chemistry changes, as well as the variation in tubing ...
The effect of transverse magnetic field parameter (Hartmann number, Ha) Reynolds number (Re) and Prandtl number (Pr) on the mixed convection flow past a semi-infinite vertical porous plate in a non-Darcian porous medium with variable viscosity and porosity, viscous dissipation and fluid-solid thermal conductivity ratio in the presence of plate transpiration (lateral mass flux) is investigated theoretically and numerically using Keller`s implicit finite difference scheme. It is shown that the Harmann number acts as a retarding force and increases the momentum boundary layer thickness, analogous to the flow against a positive pressure gradient, simultaneously decreasing local skin friction (shear stress). The heat transfer rate is however enhanced by the magnetic field (for positive values of the Eckert number) since the fluid is heated and temperature gradients become reduced between the fluid and the plate, with important ...
... ions. MATERIALS AND METHODS Cell Culture Culture of NT2/D1 cells was carried out as described previously (18, 19). NT2 cells were plated at a density of 2. ... ...
U3Si2 Al fuel plate is one of the dispersion fuel structure materials recently developed and widely used in research reactors. The mechanical properties of this structural material, especially the fatigue performance, are strongly dependent on its fabrication process. To investigate the effects of these processing technologies, the fatigue tests for the different specimens were carried out. The S N curves indicate that the fabrication processing technologies of U3Si2 fuel plate, such as the addition of U3Si2 particles into aluminum powder to form the fuel meat, holding and rolling the processes of meat and cladding of 6061-Al alloy, plays an important role in improving the mechanical properties and fatigue performance of this fuel plate. In addition, some factors that influence the crack initiation and propagation are summarized based on the fatigue images that are in situ observations with SEM. The critical criterion for ...
AIMS: To evaluate the sensitivity of the Roche Cobas, Roche Amplicor plate kit, ligase chain reaction (LCR), and an in house polymerase chain reaction (PCR) by titration of purified elementary bodies...Full Text Available
Rapid corrosion of PWR steam generator carbon steel support structures and consequential denting of steam generator tubes led to investigation of alternative support designs and materials. In recent designs of steam generators the carbon steel drilled hole tube support plate has been replaced by one of quatrefoil or trefoil shape to minimize the contact area. These plates are now made of more corrosion resistant chromium steel (approx. 12%Cr) to ensure that they are less vulnerable to attack in the event of adverse boiler water chemistry. This study was initiated to examine the corrosion behavior of a range of chromium steels in the acid chloride environments characteristic of tube/support plate crevices under adverse boiler water conditions. Objectives of the study were to: 1) determine the relative susceptibility of candidate tube support plate steels to acid chloride corrosion; 2) investigate the ...
Mice homozygous for the recessive gene achondroplasia (cn) aged 16 and 17 days and some homozygotes aged 22-34 days have disruptions in the growth of the proximal tibial growth plate which are due solely...Full Text Available
The use of isokinetic equipment and the leg press exercise have been major components of rehabilitation for the past several years when redeveloping muscular strength. Recently, closed kinetic chain...Full Text Available
believe the system is similar to the face-on spiral and companion known as M51, the Whirlpool Galaxy. Tomorrow's picture: plates known < | Archive | Index | Search | Calendar |...
BackgroundThis in vitro study was conducted to compare the accuracy of two digital image receptors in identifying the location of tip of a fine endodontic file and radiographic apex...Full Text Available
Measurements of the rate of heat transfer, enhanced by electroconvection, between two parallel plates have been carried out. Results show that the non-dimensional heat flux, or the Nusselt number, increases when an electric field acts on an injected space charge within the insulating liquid. The motion of the liquid depends on the electrical forces (Coulomb force) and the buoyancy effects have little or no influence. This is evident from steady state and time dependent results which show that for a given voltage, the Nusselt number takes the same value no matter what the flux of heat supplied to the bottom plate.
A line-to-plate reactor was set-up in the experimental study on the application of nanosecond pulsed corona discharge plasma technology in environmental pollution control. Investigation on the attenuation and distortion of the amplitude of the pulse wave front and the discharge image as well as the waveform along the corona wire was conducted. The results show that the wave front decreases sharply during the corona discharge along the corona wire. The higher the amplitude of the applied pulse is, the more the amplitude of the wave front decreased. The wave attenuation responds in a lower corona discharge inversely. To get a higher efficiency of the line-to-plate reactor a sharp attenuation of the corona has to be considered in practical design.
The present process allows to eliminate the corrosion products formed on the tube plates and in the interstices of plate-tube crosspieces of a PWR steam generator in order to avoid a corrosion phenomenon which may cause denting by presence of oxides. The process consists in applying on these oxides at about 50-100 degrees, an aqueous solution containing 6-8% of gluconic acid, 3-5% of citric acid, about 0.5% of a corrosion inhibitor and ammonia until a pH of 3-9.5 is obtained.
Posttraumatic tibia valga is a well-recognized complication following fracture of the upper tibial metaphysis in young children. We present a case of a child who developed a valgus deformity following fracture of the proximal tibia and fibula in which quantitative bone scintigraphy at 5 months after injury demonstrated increased uptake at the proximal tibial growth plate with proportionally greater uptake on the medial side. This finding suggests that the valgus deformity in this patient was due to a relative increase in vascularity and consequent overgrowth of the medial portion of the proximal tibial physis.
Posttraumatic tibia valga is a well-recognized complication following fracture of the upper tibial metaphysis in young children. We present a case of a child who developed a valgus deformity following fracture of the proximal tibia and fibula in which quantitative bone scintigraphy at 5 months after injury demonstrated increased uptake at the proximal tibial growth plate with proportionally greater uptake on the medial side. This finding suggests that the valgus deformity in this patient was due to a relative increase in vascularity and consequent overgrowth of the medial portion of the proximal tibial physis.
Minimum weight design is an important criterion in aircraft and spacecraft because it allows either an increased pay-load or higher performance. As a result, the use of composite sandwich panels has grown due to their light weight and high rigidity. In order to further increase the efficiency of these structures, designers have used different materials in different shapes in the facesheets and in the core. One of the most recent innovations has been the use of a uniform net of carbon fibre/epoxy as the facesheets. In the present study, the optimal design of sandwich plates with heterogeneous, facesheets is treated. The plate mass is minimized, considering the first natural frequency and certain failure loads as constraints. Weight reduction is obtained by defining a nonuniform distribution of composite material in the facesheets. Initially, the facesheets are assumed to be constructed of composite strips in a regular pattern. During the ...
In PWR steam-generators, the crevice between tube and tube-support plate tends to fill with porous deposits during operation and acts as a concentration site for chemicals in the boiler water, which may lead to corrosion of the tube and tube-support-plate. The rate of concentration, the magnitude of the concentration factor and the rate of release of solute when conditions change are important parameters for devising strategies to minimize corrosion. Values of these parameters for salt concentration have therefore been measured in a laboratory simulation of the crevice and are used to formulate a model of the concentrating process.
During a high temperature treatment of the radioactive wastes that contain ruthenium, some ruthenium is volatilized and released to the off gas system. The volatilized ruthenium is removed with a scrubber and an adsorber. It was expected that the scrubber was one of the most effective equipments to remove ruthenium and the decontamination factor of the scrubber was studied. The experimental apparatus was simulated as part of an actual perforated plate column scrubber. The non-radioactive ruthenium which simulated the radioactive ruthenium was volatilized and fed into the scrubber. The decontamination factor of the scrubber was determined by the ratio of the ruthenium concentration at the inlet and outlet of the scrubber off gas stream. The results showed that the scrubber removed the volatile ruthenium effectively as expected.
A 20-cell PEFC stack was designed and built. Resin impregnated graphite was used as bipolar plate material. The air cooling of the stack was optimized by introducing high surface structures into the open space of the cooling plates. At {eta} (H{sub 2} LHV) = 0.5 a power of 880 W was obtained under conditions of low gas-pressures of 1.15 bar{sub a}. The auxiliary power for process air supply and cooling at 880 W power is less than 7% of the power output, indicating that the described system may be operated at a high efficiency. (author) 5 figs., 2 refs.
Electron beam therapy has often been used for radiation therapy of carcinomas of the buccal mucosa, though side effects, including stomatitis and dermatitis, are known to exist. We experimented using the additional back scatter and transit with the phantom under a lead plate within the irradiation field, in order to better focus the dose on the target volume moreover, we fabricated a mouthpiece fitted with a lead plate shaped to the target volume, and with respect to the influence of the mouthpiece on stomatitis and dermatitis, obtained good clinical results. (author).
Electron beam therapy has often been used for radiation therapy of carcinomas of the buccal mucosa, though side effects, including stomatitis and dermatitis, are known to exist. We experimented using the additional back scatter and transit with the phantom under a lead plate within the irradiation field, in order to better focus the dose on the target volume moreover, we fabricated a mouthpiece fitted with a lead plate shaped to the target volume, and with respect to the influence of the mouthpiece on stomatitis and dermatitis, obtained good clinical results. (author).
The present contribution deals with the thermophoresis particle deposition and thermal radiation effects on the flow, heat and mass transfer characteristics in a viscous fluid over a semi-infinite vertical porous plate. The governing boundary layer equations are written into a dimensionless form by similarity transformations. The transformed coupled nonlinear ordinary differential equations are solved numerically by means of the fourth-order Runge?Kutta method with a shooting technique. The effects of different parameters on the dimensionless velocity, temperature, and concentration profiles are shown graphically. In addition, results for the local skin-friction coefficient, the local Nusselt number, and the local Sherwood number are tabulated and discussed.
The present contribution deals with the thermophoresis particle deposition and thermal radiation effects on the flow, heat and mass transfer characteristics in a viscous fluid over a semi-infinite vertical porous plate. The governing boundary layer equations are written into a dimensionless form by similarity transformations. The transformed coupled nonlinear ordinary differential equations are solved numerically by means of the fourth-order Runge-Kutta method with a shooting technique. The effects of different parameters on the dimensionless velocity, temperature, and concentration profiles are shown graphically. In addition, results for the local skin-friction coefficient, the local Nusselt number, and the local Sherwood number are tabulated and discussed.
This paper describes detection of electro-discharged machine (EDM) defects in magnetic steam generator (SG) tubes of Monju fast breeder reactor (FBR). The EDM defects are located under support plate (SP), on the outer tube surface and they are detected by a remote field eddy current probe. Using the experimental measurements and a multi frequency algorithm, the defect signal can be extracted from the SP signal. The parameters of the multi-frequency algorithm were calculated by comparing SP measurements with two-dimensional finite element simulations (FEM). (author)
The problem of denting in steam generators leads to change in the conception of the tube support plates. A new material is now used for this component, a 13% Cr steel, which composition has been adjusted for weldability and mechanical resistance criteria. The geometry of trefoil support plate (TSP) has also been improved, using a broached TSP (quadrifoiled holes) instead of a drilled TSP. Tests have been performed on 13% Cr and C-steel broached TSP, and drilled TSP, to confirm the better resistance to denting of this new configuration.
The chemical reaction effect on an unsteady magnetohydrodynamic (MHD) flow past a semi-infinite vertical porous plate with viscous dissipation is analyzed. The governing equations of motion, energy, and species are transformed into ordinary differential equations (ODEs) using the time dependent similarity parameter. The resultant ODEs are then solved numerically by a finite element method. The effects of various parameters on the velocity, temperature, and concentration profiles are presented graphically, and the values of the skin-friction, Nusselt number, and Sherwood number for various values of physical parameters are presented through tables.
Steam generators in PWR plants have been subject to denting corrosion as a result of nonprotective magnetite forming on the carbon steel support plate causing the voluminous corrosion product that eventually crimps (dents) the heat transfer tube at the support plate interface. This project was designed to determine the causes of denting and the usefulness of water chemistry changes meant to arrest denting. This volume of the final report describes laboratory research on the correlation of water chemistry, superheat, and oxygen ingress with denting in steam generators.
An aspiration cover is proposed for the site of loading a belt conveyer including a housing arranged above the belt conveyer in whose cover there is an aspiration sleeve and a discharge chute from the upper wall and a guide having a cushioning plate on the lower end. It is distinguished by the fact that in order to improve the effectiveness of removing dust by decreasing the volume of aspirated air, the cover between the aspiration sleeve and the upper wall of the loading chute is convex in the inside of the housing and has a smooth connection to the upper wall of the discharge chute turned towards the cushioning plate.
The approach-to-critical measurements reported were for a plate-type fuel element where the height of the water moderator and side and top reflector were increased. Measurements were also performed with each of the two annuli of the fuel element to verify both the presence of boron in the fuel plates and the proper uranium loading prior to assembly of the two annuli for full submersion measurements. Measurements were also performed with detectors external to the reflector (> 15 cm of water on top, bottom, and side) for the assembled, submerged HFIR fuel element.
A new simple multi-well plate-based assay to determine monocyte differentiation-inducing activity was developed. It is based on the increase of macrophage adherence after the induction of monocyte differentiation. The assay was conducted using a human monocytic leukemia cell line, THP-1, treated with either 12-O-tetradecanoylphorbol 13-acetate or cytokines, such as tumor necrosis factor-alpha and interferon-gamma. This method is sensitive and easy to perform, especially in case of analyzing a large number of samples. PMID:17920620
A new simple multi-well plate-based assay to determine monocyte differentiation-inducing activity was developed. It is based on the increase of macrophage adherence after the induction of monocyte differentiation. The assay was conducted using a human monocytic leukemia cell line, THP-1, treated with either 12-O-tetradecanoylphorbol 13-acetate or cytokines, such as tumor necrosis factor-? and interferon-?. This method is sensitive and easy to perform, especially in case of analyzing a large number of samples.
The scenario of the development of a new procedure for cutting out the broken protective wells for thermocouples inside the deep holes in the tube plate in the moisture re-heater (MSR) at Daya Bay nuclear power station is presented. Focused in the innovation and improvement of the self-made tools, the new procedure produced an effective method to cut out swing long inserts stuck inside the deep holes. (authors)
The object of the present study is to develop a high performance evaporator for automotive air conditioner. The experiment has been conducted on evaporative heat transfer coefficient inside a plate type heat exchanger with a sharp 180-degree turn flow. The test plates have different formed surface, cross-ribboned channel and elliptical-ribbed channel. Also experimental study has been performed to determine optimal design in elliptical-ribbed plate heat exchanger with different turn clearance. In addition to the above experiments, refrigerant behavior and surface temperature distribution in the plate heat exchanger were observed using color thermo viewer(infrared thermometer). In this experiment, working fluid was used R-12 and test conditions were as follows : (1) saturation pressure of 2,116 kg/cm{sup 2}, (2) mass fluxes of 40 to 70 kg/m{sup 2} s, (3) heat fluxes of 4,500 to 7,300 W/m{sup 2}, (4) inlet ...
Lithium (Li) plating-stripping reaction properties at the lithium phosphorus oxynitride glass electrolyte (LiPON)/copper thin film (Cu) interface is improved by the insertion of nano-thickness platinum (Pt) layer at the interface. The LiPON films are formed on mirror-polished lithium-ion conductive solid electrolyte sheets, and current collector thin films of Li, Cu-Pt multi layer, and Cu are formed on the LiPON films. The plating-stripping reactions at the LiPON/current collector films interface are carried out by galvanostatic and potential sweep measurements. Galvanostatic measurements reveal that Pt layer insertion reduces the overvoltage of the reaction and improves its coulomb efficiency. Also, cyclic voltammetry measurement suggests formation of Li-Pt alloys at higher voltages than 0 V (vs. Li/Li{sup +}) during the lithium plating process. Scanning electron microscopy observation clarifies that platinum insertion ...
For higher U-loading in low-enriched U-10 wt.%Mo fuels, monolithic fuel plate clad in AA6061 is being developed as a part of Reduced Enrichment for Research and Test Reactor (RERTR) program. This paper reports the first characterization results from a monolithic U-10 wt.%Mo fuel plate with a Zr diffusion barrier that was fabricated as part of a plate fabrication campaign for irradiation testing in the Advanced Test Reactor (ATR). Both scanning and transmission electron microscopy (SEM and TEM) were employed for analysis. At the interface between the Zr barrier and U-10 wt.%Mo, going from Zr to U(Mo), UZr_2, #gamma#-UZr, Zr solid-solution and Mo_2Zr phases were observed. The interface between AA6061 cladding and Zr barrier plate consisted of four layers, going from Al to Zr, (Al, Si)_2Zr, (Al, Si)Zr_3 (Al, Si)_3Zr, and AlSi_4Zr_5. Irradiation behavior of these intermetallic phases is discussed based on ...
Because of questions regarding current density and inductance estimates of the Atlas oil transmission line in the region where the vertical plates connect to the disk line, calculations using the 3D FE program Flux3d were initiated. Flux3d inductance values are nearly that estimated by D. Scudder. Calculations for three base designs of E. Ballard and D. Pierce were completed where several variations for each base design were used to determine the important parameters affecting inductance and to check inductance consistency. Flux3d showed for the first base design a very high current density of 36MA/m at the connection between the vertical and horizontal ground plates resulting in a magnetic pressure of 120 kpsi. The second base design modified this connection to reduce the current density to 20MA/m and 36 kpsi and for design 3 current density is 17MA/m. Maximum current density on the hot plates is 20MA/m for all 3 designs. ...
This work describes the use of volatile halocarbons in a pulp mill effluent, including chloroform, bromodichloromethane, and tri- and tetrachloroethylene, as tracers for the distribution and movements of effluent currents in a receiving water bay (Jackfish Bay) on the northern shore of Lake Superior. The results indicate the simplicity and usefulness of the technique and the significantly improved resolution of effluent plume delineation over the customary use of conductance profiles. Concentration patterns of the effluent volatiles suggest counterclockwise circulation of bay water that mixes with inflowing lake water at the eastern reach of the outer bay. The distribution of volatile contaminants is governed by the thermal regime of the receiving waters. During the summer months, the effluent plume wedges between the thermocline and epilimnion, mixing into the surface waters as the distance from the input source increases. In the fall, the colder effluent plume ...
Annona reticulata L. possesses many traits desirable in other edible annonas, and hybridization is the simplest means to combine desirable features of related species. In this study, A. reticulata was hybridized with atemoya (A. cherimola Mill.??A. squamosa L.), and 250 trispecies hybrids were studied for 28 traits (12 tree traits and 16 fruit traits) with the objective of salvaging useful genes from the three edible annonas and determining the extent of variation in the progeny. The heterozygous nature of Annona spp. and simultaneous segregation of three distant genomes resulted in a tremendous heterogeneity in the progenies. The fitness of the progenies ranged from very vigorous to very weak, with a wide range of values for tree height (1.75?5.9?m), canopy spread (1.15?5.07?m) and trunk...
With the aim of studying the magnetic properties of reduced-dimensionality magnetic systems we have patterned 250 nm- and 500 nm-size square elements on Fe/NiO layers by 30 keV Ga{sup +} focused ion beam (FIB) milling, varying beam current and pixel dwell time. By high resolution scanning electron microscope (SEM) imaging and atomic force microscopy (AFM) analysis we found that island size decreases from the nominal value by increasing the beam current and features sharpness improves on increasing the dwell time. The top surface of the isolated features has a pronounced edge bending which may be as high as 9 nm with respect to the flat inner area of the island and decreases as dwell time grows. By varying the ion fluence we found that such a shape is related to a surface swelling effect occurring at low ion fluence in the irradiated areas. The swelling-related damage at the edges is expected to influence the magnetic properties of the patterned features.
With the aim of studying the magnetic properties of reduced-dimensionality magnetic systems we have patterned 250 nm- and 500 nm-size square elements on Fe/NiO layers by 30 keV Ga"+ focused ion beam (FIB) milling, varying beam current and pixel dwell time. By high resolution scanning electron microscope (SEM) imaging and atomic force microscopy (AFM) analysis we found that island size decreases from the nominal value by increasing the beam current and features sharpness improves on increasing the dwell time. The top surface of the isolated features has a pronounced edge bending which may be as high as 9 nm with respect to the flat inner area of the island and decreases as dwell time grows. By varying the ion fluence we found that such a shape is related to a surface swelling effect occurring at low ion fluence in the irradiated areas. The swelling-related damage at the edges is expected to influence the magnetic properties of the patterned features.
Repassivation behavior and IGA resistance of nickel base alloys containing 0#approx#30 wt% chromium was investigated in high temperature acid sulfate solution. (1) The repassivation rate was increased with increasing chromium content. And so the amounts of charge caused by the metal dissolution were decreased with increasing chromium content. (2) Mill-annealed Alloy 600 suffered IGA at low pH environment below about 3.5 at the fixed potentials above the corrosion potential in 10%Na_2SO_4+H_2SO_4 solution at 598K. On the other hand, thermally-treated Alloy 690 was hard to occur IGA at low pH environments which mill-annealed Alloy 600 occurred IGA. (3) It was considered that the reason, why nickel base alloys containing high chromium content such as Alloy 690 (60%Ni-30%Cr-10%Fe) had high IGA/SCC resistance in high temperature acidic solution containing sulfate ion, is due to both the promotion of the repassivation and the suppression of the film ...
Lutein is a yellow pigment found in common foods that promotes the health of eyes and skin and is associated with reduced risk of age-related macular degeneration and cataracts. In the present study, selected high-lutein wheat and corn were milled into wholegrain flours by two mills to improve flour uniformity. The high-lutein and lutein-fortified wholegrain flours were processed into breads, cookies, and muffins to study lutein stability during baking and subsequent storage. Lutein and its isomers were separated, identified, and quantified by LC-UV/vis and LC-MS following extraction with water-saturated 1-butanol. Baking resulted in a significant reduction in all-trans-lutein and the formation of cis-lutein and cis-zeaxanthin isomers. Subsequent storage at ambient temperature had a slight impact on the content of all-trans-lutein. Effects of processing were more pronounced in lutein-fortified products, and the degradation rate of lutein was ...
The production of the uranium mine Zirovski Vrh ceased in 1990. The main remaining problem of the remadiation are mine and mill tailings. The uranium mine Zirovski Vrh has one mill tailings site Borst and one waste pile Jazbec. According to the Act on protection against ionising radiation and nuclear safety which was adopted by the Parliament in 2002, they are classified as radiation facilities. Slovenian Nuclear Safety Administration (SNSA) is authorised for issuing a mandatory consent to mining work. The SNSA prepared the initial proposal of content of the safety report for the mine waste pile Jazbec. In 2005, according to the detailed content of this document, the public company Zirovski Vrh Ltd prepared the safety report which was examined by an authorised expert for radiation and nuclear safety. After a careful revision of the safety evaluation report, the consensus for mining work shall be issued by the SNSA. After finishing the mining ...
TRACI, a model based on the physical mechanisms governing the radon transport in unsaturated soils, has been developed to evaluate the radon flux density at Uranium Mill Tailings (UMT) covers surface. First, moisture contents in the soil, induced by weather conditions, are calculated. Then, radon concentrations in the air-filled pore space, and radon flux density at the soil surface, are deduced from a transport model which takes account for diffusion and convection in the pore space. To check the hypothesis used in TRACI and the efficiency of cover layers, an in situ study was launched in 1997 with the French uranium mining company, COGEMA. It consists of continuous measurements of moisture contents, suctions, radon concentrations at various depths inside an UMT cover, and flux density at its surface. The first analysis made on in situ observations shows that radon concentrations and flux density, calculated with a steady-state diffusion model using monthly ...
Focused ion beam (FIB) milling is a powerful and versatile tool for the maskless fabrication of structures and devices at micro- and nanometer scales. The approach is based on the milling and deposition capabilities of a focused ion beam, where the latter is achieved by ion-beam-assisted decomposition of a metalorganic gas precursor of the specific material that has to be deposited. The combination of FIB and scanning electron microscopy in the same unit (so-called dual-beam unit) further expands the capabilities of the approach by the possibility of performing electron-beam-assisted deposition and inspection. Permalloy nanowires with electrical contacts patterned by FIB-Pt deposition were prepared in the dual-beam unit. Various types of notches to pin magnetic domain walls were additionally fabricated by means of FIB. The fabrication parameters for a structural modification of the Permalloy structures without too strongly affecting the ...
We consider two-dimensional large N gauge theory with D adjoint scalars on a torus, which is obtained from a D+2 dimensional pure Yang-Mills theory on T^{D+2} with D small radii. The two dimensional model has various phases characterized by the holonomy of the gauge field around non-contractible cycles of the 2-torus. We determine the phase boundaries and derive the order of the phase transitions using a method developed in an earlier work (hep-th/0910.4526), which is nonperturbative in the 'tHooft coupling and uses a 1/D expansion. We embed our phase diagram in the more extensive phase structure of the D+2 dimensional Yang-Mills theory and match with the picture of a cascade of phase transitions found earlier in lattice calculations (hep-lat/0710.0098). We also propose a dual gravity system based on a Scherk-Schwarz compactification of a D2 brane wrapped on a 3-torus and find a phase structure which is similar to the phase diagram found in the ...
In the present work the hydrogen desorption properties of nanostructured magnesium hydride (MgH2) synthesized by controlled reactive mechanical milling (CRMM) of elemental Mg powder under hydrogen are investigated. A profound effect of the particle size of synthesized MgH2 hydride on its hydrogen desorption characteristics measured by differential scanning calorimetery (DSC) has been found. All synthesized MgH2 powders are characterized by a double hydrogen desorption peak. Furthermore, below a certain threshold particle size the DSC desorption temperature of the peak doublet starts decreasing rapidly with decreasing of the mean hydride powder particle size (expressed as equivalent circle diameter-ECD). In contrast, the nanograin (crystallite) size of MgH2 does not seem to have apparent effect on the DSC desorption temperature. It is also observed that for powder particles smaller than some threshold value, X-ray diffraction shows the presence of two polymorphic ...
Pacific Northwest Laboratory (PNL) is investigating the use of a rock armoring blanket (riprap) to mitigate wind and water erosion of an earthen radon suppression cover applied to uranium mill tailings. Because the radon suppression cover and the tailings must remain intact for up to 1000 years or longer, the riprap must withstand natural weathering forces. This report is a review of information on rock weathering and riprap durability. Chemical and physical weathering processes, rock characteristics related to durability, climatic conditions affecting the degree and rate of weathering, and testing procedures used to measure weathering susceptibilities have been reviewed. Sampling and testing techniques, as well as analyses of physical and chemical weathering susceptibilities, are necessary to evaluate rock durability. Many potential riprap materials may not be able to survive 1000 years of weathering. Available techniques for durability testing cannot adequately ...
The plastic displacements around Knoop indentations made in hard titanium/aluminum multilayered films on soft aluminum alloy substrates have been studied. Indentations were cross-sectioned and imaged using the focused-ion-beam (FIB) milling and high-resolution scanning electron microscopy (SEM), respectively. The FIB milling method has the advantage of removing material in a localized region without producing mechanical damage to the specimen. The micrographs of the cross-sectioned indentations indicate that most of the plastic deformation around the indentation is dominated by the soft aluminum substrate. There is a very small change in the multilayered film thickness around the indentation{emdash}less than 10{percent}. The plastic deformation of the thin film resembles a membrane being deflected by a localized pressure gradient across the membrane. Stress-induced voids are also observed in the multilayered film, especially in the area around ...
At tandem cold rolling mills in Kawasaki Steel, by means of applying newly developed strip longitudinal (rolling) and transverse gauge control systems, high accuracy of thickness of within {+-}0.5 % has been achieved over the full length and full width of cold rolled strip, as gauge accuracy in a coil in longitudinal and transverse directions has become an extremely important quality control item in the manufacturing of cold rolled sheets due to the stricter quality requirements of customers, in recent years. The longitudinal gauge accuracy has been improved by the development of a high-response drive system for a mill mair motor, an all-stands gauge control system and a dynamic set-up control system. The transverse gauge accuracy has been improved by applying a one-side tapered work roll shifting method and the development of an edge drop control system in terms of the optimum use of an edge drop sensor. (author)
Reactive milling of NiO + Al powder mixture resulted in the formation of NiAl-Al_2O_3 nanocomposite powders, with a crystallite size of about 20 nm. The Hall-Williamson analysis revealed that NiAl showed an orientation dependent crystallite size after short processing time and orientation dependent internal strain after long milling time. Both anisotropies were removed by heating the powders in the differential scanning calorimetry. Calorimetric studies showed one exothermic effect attributed to the reduction reaction of NiO and endothermic one associated with melting of Al. Two methods were applied for powders compaction: resistance sintering and pulse electric discharge. In both cases the densities of abut 90% of the theoretical value were achieved. A significant increase in average NiAl crystallites size in compacted samples was observed, up to several hundreds of nanometers.(author)
The possibility of oxidizing at a PbO{sub 2} anode the phenols and polyphenols, present in the olive oil mill wastewater, has been studied as a pre-treatment for the submission of such wastewater to the traditional biological treatments. The results obtained operating at current densities ranging 500 to 2000 A/m{sup 2} show that it is possible to reduce the concentration of the phenolic components, which interfere with the biological treatments, down to low values without decreasing too much the total organic content of the wastewater. [Italian] E' stata studiata la possibilita' di ossidare anodicamente i componenti fenolici delle acque reflue di frantoio, quale pretrattamento delle stesse prima del loro invio ai processi di trattamento biologico. I risultati ottenuti impiegando PbO{sub 2} quale materiale anodico e operando con densita' di corrente comprese tra 500 e 2000 A/m{sup 2} mostrano come sia possibile eliminare, o almeno ...
Both the increased complexity of integrated circuits, resulting in six or more levels of integration, and the increasing use of flip-chip packaging have driven the development of integrated circuit (IC) failure analysis tools that can be applied to the backside of the chip. Among these new approaches are focused ion beam (FIB) tools and processes for performing chip edits/repairs from the die backside. This paper describes the use of backside FIB for a failure analysis application rather than for chip repair. Specifically, they used FIB technology to prepare an IC for inspection of voided metal interconnects (lines) and vias. Conventional FIB milling was combined with a super-enhanced gas assisted milling process that uses XeF{sub 2} for rapid removal of large volumes of bulk silicon. This combined approach allowed removal of the TiW underlayer from a large number of Ml lines simultaneously, enabling rapid localization and plan view imaging of ...
Alloy 800 from three different commercial heats have been continuously cycled and cycled with a hold period at 922/sup 0/K. The starting microstructures of these heats reflects an inherently wide spectrum of possibilities for Alloy 800. The amounts and morphologies of the TiC and M/sub 23/C/sub 6/ carbides are different among the heats. During cycling, M/sub 23/C/sub 6/ forms intragranularly in a solution annealed heat. This precipitation contributes to the cyclic hardening. Both mill annealed heats of Alloy 800 are stable to carbide precipitation during cycling. The heat with the lower carbon content formed ..gamma..' during cycling but the volume fraction was too low to contribute to hardening. The inclusion of hold periods caused the dislocation substructure to become more diffuse in the mill annealed heats. The cyclic hardening was enhanced with the inclusion of the hold periods but this was not due to any microstructural change ...
In this letter we present a derivation, from the D0-brane picture, of the background monopole field and in general of the full dynamics of the Yang-Mills theory on the dielectric D2-brane of Myers. To do this we study the large N limit of the fuzzy sphere relevant to the dielectric solution. In contrast to the usual interpretation where the commutative D2-brane picture arises directly from the large N limit of the D0-brane picture, we find that a residual non-commutativity must be preserved in order to make the connection by means of the Seiberg-Witten map.
Defects ~10 nm in size, with number densities ~10^{10} cm^{-2}, form spontaneously beneath ion-milled, etched, or HF-dipped silicon surfaces examined in our Ti-ion getter-pumped transmission electron microscope (TEM) after exposure to air. They appear as weakly-strained non-crystalline intrusions into silicon bulk, that show up best in the TEM under conditions of strong edge or bend contrast. If ambient air exposure is <10 minutes, defect nucleation and growth can be monitored {\\em in situ}. Possible mechanisms of formation are discussed.
The rate at which full-scale technology transfer takes place depends on the quality of the supply companies, i.e. training, organisational development and product infrastructure. These parameters are discussed for the example of a water mill, and a flow diagram is presented. [Deutsch] Wie rasch ein umfassender Transfer in Frage kommt, entscheidet sich mit der Qualitaet und dem Niveau der zuliefernden Betriebe. Hierbei sind Ausbildung, Organisationsentwicklung und Produktionsinfrastruktur besonders angesprochen. Fuer eine Wassermuehle werden diese Parameter konkret eroertert und an Durchlaufdiagrammen erlaeutert. (GL)
The DOE`s clean-up of its nuclear complex require the development of innovative technologies to convert soils contaminated by hazardous and/or radioactive wastes to forms which can be readily disposed in accordance with current waste disposal methods. The unique features of Votec CMS technology should make it particularly cost-effective process for the vitrification of soils, sediments, sludges, and mill tailings containing organic metallic and/or radioactive contaminants. This article describes the technology (Votec`s combustion and melting system), the results of testing, the demonstration plant system, and summarizes the future schedule and the equipment needed. 3 figs., 3 tabs.
Lithium orthosilicate (Li_4SiO_4) powder was synthesized by the solid-state reaction of lithium oxide with amorphous silica, and the effects of fabrication parameters on the structural characteristics of the product were investigated. Processing considerations such as milling media, drying technique, calcination time and temperature, pressing behavior, sintering time and temperatures, and impurity concentration were addressed. The initial powder particle size was observed to be important in achieving high sintered density, with densities as high as 98% TD achieved with a particle size of approximately 1 #mu#m. 9 refs., 6 figs.
Radiological hazard in uranium mining and milling operations are primarily due to exposure to external beta and gamma radiation as well as to airborne radionuclides which consist of radon and its short-lived daughter products. In May 1981 a radiological survey programme was performed in order to make a general assessment of the radiation hazards associated with the uranium mines and the Uranium Pilot Plant operated by the M.T.A. Institute in the Koprubasi district of the Manisa province. In this paper a preliminary radiological risk evaluation attempt is presented based on the radiation and radioactivity measurements performed in this district in May 1981.
This paper reported on a study in which partial discharge (PD) measurements were performed on 6 underground transmission cable circuits to determine the effectiveness of PD measurements on fluid fill cables. The cables were between 37 and 56 years old. PD activity was detected from the terminations of H11L and H3L Cable 2. However, for cables from H3L Basin TS to Mill Street junction, PD activity was detected originating from within the main cable insulation.
Abstract in english Odontopus brevirostris (Hustache, 1936) feeding on Annona squamosa L., A. cherimola Mill., A. glabra L., and A. muricata L. was observed. The last three host plants are recorded for the first time. The endophitic oviposition occurs in the veins of the ventral surface of the young leaves. The larvae, leaf miners, eat the parenchyma and the adults make small holes in the leaves. The pupation occurs in spherical cocoons protected by a sort of nest (pupation chamber) between the two epidermal layers.
A study was conducted to examine the energy consumption in existing and new hog farming facilities and to analyse the potential for increased natural gas use in the Saskatchewan hog industry. Existing heating/cooling, ventilation and feed mill equipment choices offer possibilities for running on electricity, natural gas or propane. Energy costs are lowest when natural gas is used. To put the study in context, an overview of the Saskatchewan hog industry was provided. The potential increase in natural gas use in hog production by year 2005 was estimated. 10 refs., 6 tabs., 8 figs.
Using the [sup 57]Fe Moessbauer spectroscopy, the microscopic behavior of Fe powders has been investigated during and after the mechanical alloying (MA) process for Al-Fe and Ag-Fe systems. A repeated rolling method as well as a conventional ball-milling method are employed in order to understand the microscopic process of the kneading of Al and Fe powders during their MA and the resultant powders show quite similar Moessbauer spectra suggesting that the kneading by an impact between colliding balls is the same process as that of the thickness reduction by cold rolling. Moessbauer spectra show clearly the occurrence of the mutual atomic dispersion for the thermodynamically immiscible Ag-Fe system. (orig.).
A study was made of the variation in strength characteristics of group IV transition metal carbon nitrides alloyed with carbides or group V metal nitrides. A complex solid solution of titanium-niobium carbonitride was preliminarily synthesized to a homogeneous equilibrium state and then crushed. The calculated quantity of binder metal was added as elemental powders, the mixture was vibration ball milled in ethanol and the plasticized charge was used to press experimental specimens for mechanical testing. The studies showed that the high-temperature strength properties of the new cermet are superior to standard type KNT. The material is thus promising for use in the manufacture of tools. 8 references, 3 figures.
This monograph gives a detailed and pedagogical account of the geometry of rigid superspace and supersymmetric Yang-Mills theories. While the core of the text is concerned with the classical theory, the quantization and anomaly problem are briefly discussed following a comprehensive introduction to BRS differential algebras and their field theoretical applications. Among the treated topics are invariant forms and vector fields on superspace, the matrix-representation of the super-Poincare group, invariant connections on reductive homogeneous spaces and the supermetric approach. Various aspects of the subject are discussed for the first time in textbook and are consistently presented in a unified geometric formalism.
The petroleum sector is highly significant for the Norwegian economy. Its share of gross domestic product, exports and total government revenues has been substantial over the past two decades, reaching a particularly high level in 2000 and 2001. The principal reason why revenues were so high in these two years is a combination of high oil prices, a strong USD against the NOK and historically high petroleum production. The share of petroleum investment in total capital spending in the Norwegian economy was at its highest in the early 1990s. Total investment in the petroleum sector has been above NOK 40 bn every year since 1992, and peaked in 1998 at roughly NOK 80 bn. Capital spending declined to around NOK 56.9 bn in 2001. The government's most important revenue sources in recent years have been cash flow from the state's direct financial interest (SDFI) and from taxes. Production of crude oil has averaged around three mill barrels per day since ...
We consider a D-brane probe in the unstable string background associated with flux branes. The twist in the spacetime metric reponsible for supersymmetry breaking is shown to manifest itself in the mixing of open Wilson lines with the phases of some adjoint matter fields, resulting in a nonlocal and nonsupersymmetric form of Yang-Mills theory as the probe dynamics. This provides a setup where one can study the fate of a large class of unstable closed string theories that includes as a limit type 0 theories and various orbifolds of type II and type 0 theories. We discuss the limit of C/Z_n orbifold in some detail and speculate on the couplings with closed string tachyons.
Using near-field optical microscopy, the authors investigate propagation of channel plasmon polaritons excited in the wavelength range of 1425-1640 nm along smoothly bent and split V-shaped grooves milled in a gold film. We find that for 0.6-?m-wide and 1.1-?m-deep grooves bent with the smallest curvature radius of ?0.83 ?m, the double bend (for S bends) and splitting (for Y splitters) losses decrease for longer wavelengths approaching (in the wavelength range of 1600-1640 nm) the levels of ~0 and 0.5 dB, respectively.
The formation mechanism of the cold-rolled strip shape with high tension was studied. An advanced method to calculate the allowable variation of strip transverse profiles was established by the strip buckling criterion, which can be more properly used in cold rolling. With this method, the aim allowable variation of the product strip transverse profile and the required transverse profile range of incoming strips can be reached. Besides, this method has been successfully applied in a domestic tandem cold mill, and the transverse profile range of incoming strips suggested with this method is more practicable and complete. Consequently, the good performance is acquired.
The efficiency of NbC on WC grain coarsening in a WC-10wt.%Co hardmetal alloy was demonstrated by hardness measurement and WC granulation observation. The heterogeneous and overall grain growth were controlled. A low temperature experimentally produced NbC was used and compared to the inhibition potential of a commercial NbC powder. The results were the same in terms of structural fineness and hardness. The dispersion of the experimental NbC was not a problem, in spite of its size. The experimental NbC has very large particles, formed by agglomerates of small crystallites. During milling these agglomerates could be broken down. (orig.)
Crack arrest of fast running cracks is an important issue for the safety of steel structures. Crack arrest design can prevent fatal damage of large structures by restricting the influence of the incidents. Therefore crack arrest design is important especially for very large structure, where accidents may cause huge economical and social losses. Propagating shear fracture, long running ductile crack propagation in pipelines and brittle crack propagation in heavy thick shipbuilding steels have been investigated. For the propagating shear fracture issue, a new HLP simulation model, applicable to various backfill conditions, including underwater backfill, was developed. The proposed backfill model can be applied to the prediction of the crack arrest of propagating shear fracture under various backfill conditions. The new HLP simulation was successful in estimating full-scale burst tests with various backfill depths. The new HLP simulation for underwater pipelines indicated that propagating ...
Thermal (gas) nitridation of stainless steel alloys can yield low interfacial contact resistance (ICR), electrically conductive and corrosion-resistant nitride containing surface layers (Cr{sub 2}N, CrN, TiN, V{sub 2}N, VN, etc.) of interest for fuel cells, batteries, and sensors. This paper presents results of proton exchange membrane (PEM) single-cell fuel cell studies of stamped and pre-oxidized/nitrided developmental Fe-20Cr-4V weight percent (wt.%) and commercial type 2205 stainless steel alloy foils. The single-cell fuel cell behavior of the stamped and pre-oxidized/nitrided material was compared to as-stamped (no surface treatment) 904L, 2205, and Fe-20Cr-4V stainless steel alloy foils and machined graphite of similar flow field design. The best fuel cell behavior among the alloys was exhibited by the pre-oxidized/nitrided Fe-20Cr-4V, which exhibited {proportional_to}5-20% better peak power output than untreated Fe-20Cr-4V, 2205, and 904L metal stampings. Durability was assessed ...
Thermal (gas) nitridation of stainless steel alloys can yield low interfacial contact resistance (ICR), electrically conductive and corrosion-resistant nitride containing surface layers (Cr{sub 2}N, CrN, TiN, V{sub 2}N, VN, etc.) of interest for fuel cells, batteries, and sensors. This paper presents results of proton exchange membrane (PEM) single-cell fuel cell studies of stamped and pre-oxidized/nitrided developmental Fe-20Cr-4V weight percent (wt.%) and commercial type 2205 stainless steel alloy foils. The single-cell fuel cell behavior of the stamped and pre-oxidized/nitrided material was compared to as-stamped (no surface treatment) 904L, 2205, and Fe-20Cr-4V stainless steel alloy foils and machined graphite of similar flow field design. The best fuel cell behavior among the alloys was exhibited by the pre-oxidized/nitrided Fe-20Cr-4V, which exhibited {approx}5-20% better peak power output than untreated Fe-20Cr-4V, 2205, and 904L metal stampings. Durability was assessed for ...
The high cost of proton exchange membrane fuel cells (PEMFCs) poses a significant challenges to their commercial uptake. The bipolar plates connect the anode and cathodes of cells and separate the reactant gases, and are the most expensive components in PEMFCs. Although stainless steel can be used as a low-cost alternative in bipolar plate construction, steel is prone to electrochemical corrosion in the highly acidic PEMFC operation process. This study examined the polarization curves and ICR as a function of compaction force of a high Cr and Ni austenitic stainless steel in an environment simulating the bipolar plate under PEMFC operating conditions. The 3-electrode system consisted of a platinum (Pt) sheet, a saturated calomel electrode with a Luggin capillary contract with the used solution and the work electrode. All polarization curves were measured in a solution of H{sub 2}SO{sub 4} in order to simulate the aggressive ...
A numerical method for studying the flow field of an under-expanded axis-symmetric jet created by a converging-diverging nozzle and impinging on a flat plate is presented. The calculation domain of interest is a region that contains all the features of the jet that leaves the nozzle and impinges onto the plate. Axial symmetry of the domain allows a reduced 2-dimensional model to be used. FLUENT software is utilized to solve the continuity, momentum and energy equations using a coupled implicit scheme. The ideal-gas law is used to determine the gas density along with a k-#epsilon# turbulence model with a special modification to account for compressibility effects. In addition, the temperature dependency of viscosity has been taken into consideration. A number of different modeling techniques are investigated including different approximations to account for the flow inside the nozzle. Performance of non-equilibrium wall functions for near-wall ...
In the present paper we estimate the effect of sodium in the in-service inspection of non-magnetic steam generators tubes using eddy current technique and eddy current probes based on a differential double bobbin coil configuration. Experimental measurements of defects signals in steam generator tubes of fast breeder reactor are compared with simulations results of a two-dimensional axisymmetric finite element code to validate a reliable electromagnetic model of the system (eddy current coils, steam generator tube, defect) when there is no sodium on the outer steam generator tube surface. The electromagnetic code is used to evaluate the sodium band and sodium layer signals when a defect is located under steam generator support plate. Using a multi-frequency algorithm, its parameters are determined in the 'no sodium condition' (there is no sodium on the outer steam generator tube surface), defects signal is enhanced during eddy currents inspection, even when the ...
Once again Brazil faces the possibility of an electricity shortage in the near future. The low level of rain and the consequent reduction of hydroelectric reservoirs (hydroelectric energy represents almost 80% the total Brazilian electricity generation) led to the dispatch of thermal plants based on natural gas and/or fuel oil. However, the recent crisis regarding the Bolivian natural gas supply to Brazil increased the risk of a shortage of this energy source. Hence, the uncertainty of the electricity supply scenario is pushing the electricity prices up in the near future. A possible alternative to increase the electricity supply is the maximization of the electricity surplus in sugarcane mills. Back in 1970's and 1980's, cogeneration plants in sugarcane mills were primarily designed to consume all bagasse, and produce steam and electricity to the process. The plants used medium pressure steam boilers (21 bar and 300 deg C) ...
Crystalline {alpha}-Fe{sub 2}O{sub 3} powder was prepared by the mechanical milling of crystalline {alpha}-FeOOH at room temperature in air. This result means that crystalline {alpha}-FeOOH is dehydrated by mechanical milling at room temperature. The obtained {alpha}-Fe{sub 2}O{sub 3} powder worked as a rechargeable electrode material in lithium ion conductive organic electrolytes. The electrodes exhibited high discharge capacities of over 1000mAhg{sup -1} corresponding to 6 Li per {alpha}-Fe{sub 2}O{sub 3} at potentials ranging from the open circuit potential to 0.5V (versus Li{sup +}/Li) in the first discharging (lithium insertion) process. This suggests that the valence deviation from Fe{sup 3+} in {alpha}-Fe{sub 2}O{sub 3} to Fe{sup 0} may be caused by electrochemical reduction. In contrast, after the first discharge, the electrodes exhibited high charge capacities of more than 700mAhg{sup -1} corresponding to 4.2 Li per {alpha}-Fe{sub ...
In the present paper a procedure is proposed for the determination of traces of Cd, Co, Mn and Cr in petroleum industry produced water by inductively coupled plasma optical emission spectrometry. The procedure is based on cloud point extraction of these metals, as their dithizonate complexes, into the surfactant-rich phase of octylphenoxypolyethoxyethanol surfactant (Triton X-114). Extractions were carried out in solutions with salinities between 10 per mille and 70 per mille. Since residual salinity in the surfactant-rich phase caused differences in its transport to the plasma, yttrium was used as an internal standard to correct for this effect. The simultaneous metal extraction procedure was optimized by response surface methodology using a Doehlert design and desirability function. Enhancement factors of 21, 21, 9 and 19, along with limits of quantification of 0.093, 0.20, 0.73 and 1.2 #mu#g L"-"1, and precision expressed as relative ...
Magnesium-based alloys are among the promising materials for hydrogen storage and fuel cell applications due to their high hydrogen content. In the present work, we investigated the hydrogen release/uptake properties of the Mg-Ti-H system. Samples were prepared from the mixtures of MgH{sub 2} and TiH{sub 2} in molar ratios of 7:1 and 4:1 using a high-energy-high-pressure (HEHP) mechanical ball-milling method under 13.8 MPa hydrogen pressure. Thermogravimetric analysis (TGA) showed that a relatively large amount of hydrogen (5.91 and 4.82 wt.%, respectively, for the above two samples) was released between 126 and 313 C while temperature was increased at a heating rate of 5 C min{sup -1} under an argon flow. The onset dehydrogenation temperature of these mixtures, which is 126 C, is much lower than that of MgH{sub 2} alone, which is 381 C. The activation energy of dehydrogenation was 71 kJ mol{sup -1}, which is much smaller than that of as-received MgH{sub 2} (153 kJ ...
This project, conducted under The United States Department of Energy (DOE) Cooperative Agreement DE-FC36-94GO10002/A002, was part of a multiple-phase effort to develop technologies that improve the energy efficiency and economics of chemical process recovery in the pulp and paper industry. The approach taken was to consider two major alternatives in two phases. Phase I, conducted previously, considered means to improve pulp mill recovery boilers using high-solids advanced combustion of black liquor; while this project, Phase la, considered means to recover kraft pulping mill process chemicals by low-temperature black liquor gasification. The principal steps previously proposed in this program were: (1) Evaluate these two technologies, high-solids advanced combustion and gasification, and then select a path forward using the more promising of these two options for future work. (2) Design and construct a pilot-scale unit based on the selected ...
Computation of effective flow properties of fluids in porous media based on three dimensional (3D) pore structure information has become more successful in the last few years, due to both improvements in the input data and the network models. Computed X-ray microtomography has been successful in 3D pore imaging at micron scale, which is adequate for many sandstones. For other rocks of economic interest, such as chalk and diatomite, submicron resolution is needed in order to resolve the 3D-pore structure. To achieve submicron resolution, a new method of sample serial sectioning and imaging using Focused Ion Beam (FIB) technology has been developed and 3D pore images of the pore system for diatomite and chalk have been obtained. FIB was used in the milling of layers as wide as 50 micrometers and as thin as 100 nanometers by sputtering of atoms from the sample surface. The focused ion beam, consisting of gallium ions (Ga+) accelerated by potentials of up to 30 kV and ...
This paper deals with preparation of PE clay nano composite specimen for transmission electron microscopy (TEM) and studying the difference between dispersion of clay in low density polyethylene using poly(hydrogen methyl siloxane) (PHMS) as coupling agent and untreated one. Argon ion milling is the conventional means by which film sections are thinned to electron transparency for TEM analysis, but this technique exhibits significant problems. In particular, selective thinning and imaging of sub-micrometer inclusions during sample milling are highly problematic. We have achieved successful results using the focused ion beam (FIB) lift-out technique, which utilizes a 30 kV Ga"+ ion beam to extract electron transparent specimens with nanometer scale precision. Using this procedure, we have prepared a number of thin film materials representing a range of structures and compositions for TEM analysis. We believe that FIB milling ...
In this work, a focused ion beam (FIB) milling process has been developed to fabricate 50 nm Bi nanowire and transistor structures using FEI-200 dual beam FIB system. For the fabrication, 50 nm bismuth film was thermally evaporated through EBL patterned PMMA windows onto SiO_2 substrates with pre-defined contact pads. Bi nanowire widths ranging from 30 nm to 100 nm have been successfully fabricated by milling out unwanted areas using 30 KeV Ga+ ion beam. A single-pixel-line ion beam blanking technique has been utilised to fabricate Bi nanowire as small as 30 nm in diameter and few micrometers long. In order to form good ohmic contacts for sub 50 nm bismuth nanowires, a drill-and-fill process has been developed using FIB to sputter away the surface oxide of bismuth after the in-situ platinum nanowire contacts deposition. To our knowledge, this is the first time a focused ion beam process has been used to fabricate bismuth nanowire. The ...
Energy use patterns and utilisation efficiencies in 40 factories producing palm kernel oil (PKO) in southwestern part of Nigeria were studied. The factories were stratified into small, medium and large scale categories based on the mode of operations and production capacities. Questionnaires were administered on the factories to obtain historical data on petrol, diesel and electricity consumption and PKO production outputs for seven years (1998-2004). Energy use efficiency indicators employed include: energy intensity (EI), energy cost per unit product (EC/P), energy ratio (ER), food energy ratio (FER) and percentage oil yield by weight. Results of the study indicated that averagely, 0.58, 0.53 and 0.74 GJ/10{sup 3} l of PKO were needed in the small, medium and large PKO factories, respectively. The average food energy ratios in the small, medium and large mills are 2.48, 2.53 and 2.14, respectively. The corresponding values of PKO conversion ratio are 0.43, 0.50 ...
Composite particles represented as TiV{sub 2.1}Ni{sub 0.3}-Raney Ni(R) were prepared by ball-milling a TiV{sub 2.1}Ni{sub 0.3} alloy with Raney Ni in the presence of 0.01 M sodium hypophosphite (NaH{sub 2}PO{sub 2}) aqueous solution as a reducing agent. The composite particles had different morphology from original TiV{sub 2.1}Ni{sub 0.3} alloy particles and TiV{sub 2.1}Ni{sub 0.3}-Raney Ni composite particles prepared by the ball-milling in the absence of the NaH{sub 2}PO{sub 2} aqueous solution. In charge-discharge cycle tests, the TiV{sub 2.1}Ni{sub 0.3}-Raney Ni(R) composite electrode showed the maximum discharge capacity of 620 mAh g{sup -1}, while its cycle durability was similar to the TiV{sub 2.1}Ni{sub 0.3} alloy electrode, which was explained from depth profiles of constituent elements by Auger electron spectroscopy (AES). In thermogravimetry (TG) and differential thermal analysis (DTA), two steps of dehydriding for hydrided TiV{sub ...
Composite particles represented as TiV_2_._1Ni_0_._3-Raney Ni(R) were prepared by ball-milling a TiV_2_._1Ni_0_._3 alloy with Raney Ni in the presence of 0.01 M sodium hypophosphite (NaH_2PO_2) aqueous solution as a reducing agent. The composite particles had different morphology from original TiV_2_._1Ni_0_._3 alloy particles and TiV_2_._1Ni_0_._3-Raney Ni composite particles prepared by the ball-milling in the absence of the NaH_2PO_2 aqueous solution. In charge-discharge cycle tests, the TiV_2_._1Ni_0_._3-Raney Ni(R) composite electrode showed the maximum discharge capacity of 620 mAh g"-"1, while its cycle durability was similar to the TiV_2_._1Ni_0_._3 alloy electrode, which was explained from depth profiles of constituent elements by Auger electron spectroscopy (AES). In thermogravimetry (TG) and differential thermal analysis (DTA), two steps of dehydriding for hydrided TiV_2_._1Ni_0_._3-Raney Ni(R) composite started from much lower ...
We present deep images of dust continuum emission at 450, 800, and 850 micron of the dark cloud LDN 1689N which harbors the low-mass young stellar objects (YSOs) IRAS 16293-2422A and B (I16293A and I16293B) and the cold prestellar object I16293E. Toward the positions of I16293A and E we also obtained spectra of CO-isotopomers and deep submillimeter observations of chemically related molecules with high critical densities. To I16293A we report the detection of the HDO 1_01 - 0_00 and H2O 1_10 - 1_01 ground-state transitions as broad self-reversed emission profiles with narrow absorption, and a tentative detection of H2D+ 1_10 - 1_11. To I16293E we detect weak emission of subthermally excited HDO 1_01 - 0_00. Based on this set of submillimeter continuum and line data we model the envelopes around I16293A and E. The density and velocity structure of I16293A is fit by an inside-out collapse model, yielding a sound speed of a=0.7 km/s, an age of t=(0.6--2.5)e4 yr, and a ...
Crenarchaea are ubiquitous and abundant microbial constituents of soils, sediments, lakes and ocean waters, yet relatively little is known about their fundamental evolutionary, ecological, and physiological properties. To better describe the ubiquitous nonthermophilic Crenarchaea, we analyzed the genome sequence of one representative, the uncultivated sponge symbiont, Cenarchaeum symbiosum. C. symbiosum genotypes coinhabiting the same host partitioned into two dominant populations, corresponding to previously described a- and b-type ribosomal RNA variants. Although synthetic, overlapping a- and b-type ribotypes harbored significant genetic variability. A single tiling path comprising the dominant a-type genotype was assembled, and used to explore the biological properties of C. symbiosum and its planktonic relatives. Out of a total of 2,066 predicted open reading frames, 36% were more highly conserved with other Archaea. The remainder partitioned between bacteria ...
Nuclear analytical techniques were applied to determine the elemental compositions of suspended and bottom sediments, collected at different sites in Haiphong harbor area (North Viet nam). The study was aimed at: 1/Understanding the origin of the sediment filling up the access channel and causing large expenditures for dredging operations. 2/Determining the background concentrations of trace elements in sediment. This would allow to detect in the future any pollution caused by the discharge of industrial wastes in the water due to the growing industrialization of the area. 3/Identifying the elements, which can be served as activatable tracers in sediment transport studies. The results obtained for the concentrations of nearly 30 elements show rather similar elemental compositions, reflecting a common origin of the sediments taken from different locations in the harbour area. The results could not allow to identify the pathway of the sediment transported to and ...
As part of an ongoing strategic research project to find barrels of radioactive waste off San Francisco, the U.S. Navy (USN), the U.S. Geological Survey (USGS), and the Gulf of the Farallones National Marine Sanctuary (GFNMS) pooled their expertise, resources, and technology to form a partnership to verify new computer enhancement techniques developed for detecting targets the size of 55 gallon barrels on sidescan sonar images. Between 1946 and 1970, approximately 47,800 large barrels and other containers of radioactive waste were dumped in the ocean west of San Francisco; the containers litter an area of the sea floor of at least 1400 km {sup 2} knows as the Farallon Island Radioactive Waste Dump. The exact location of the containers and the potential hazard the containers pose to the environment is unknown. The USGS developed computer techniques and contracted with private industry to enhance sidescan data, collected in cooperation with the GFNMS, to detect objects as small as 55 ...
We have previously shown that budded viruses of Bombyx mori nucleopolyhedrovirus (BmNPV) enter the cell cytoplasm but do not migrate into the nuclei of non-permissive Sf9 cells that support a high titer of Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) multiplication. Here we show, using the syncytium formation assay, that low-pH-triggered membrane fusion of BmNPV GP64 protein (Bm-GP64) is significantly lower than that of AcMNPV GP64 protein (Ac-GP64). Mutational analyses of GP64 proteins revealed that a single amino acid substitution between Ac-GP64 H155 and Bm-GP64 Y153 can have significant positive or negative effects on membrane fusion activity. Studies using bacmid-based GP64 recombinant AcMNPV harboring point-mutated ac-gp64 and bm-gp64 genes showed that Ac-GP64 H155Y and Bm-GP64 Y153H substitutions decreased and increased, respectively, the multiplication and cell-to-cell spread of progeny viruses. These results indicate that Ac-GP64 H155 ...
Fuel assemblies in a reactor pressure vessel are disposed in a reactor core shroud. The own weight of the fuel assembly is supported by a reactor core support plate, and is supported, for the horizontal direction, by an upper lattice plate and the reactor core support plate. A support portion for the upper portion of the fuel assembly is disposed above the fuel assembly, and a support portion for the support portion described above is joined to a shroud head by welding. The support portion for the upper portion of the fuel assembly has a network-like portion which absorbs and disperses rising force which exerted on the fuel assembly when the fuel assembly is risen by seismic forces. The rising force exerted on the fuel assembly absorbed by the network-like portion is effectively transferred to the shroud head by the support portion. With such a constitution, rising of the fuel assembly can be prevented against the seismic ...
A homogeneous turbulent mixing of coolant flows with different temperatures at the fuel assembly inlets is an important requirement to minimize hot spots in a fuel assembly of a High Performance Light Water Reactor (HPLWR). Therefore, the mixing chamber between lower core plate, flow adjuster and the mixing chamber within the cluster foot piece diffuser have been investigated using the Computational Fluid Dynamics (CFD)-code Fluent 6.1 and its implemented k-#epsilon# model. The previously presented 3D-CAD-geometry has been simplified using Gambit 2.1.2 and consists of various inlet and outlet tubes or channels in the foot piece bottom plate, the lower core plate and the flow adjuster establishing the boundaries of two consecutive mixing chambers. The temperature distribution at the inlet of the sub-channels of the cluster fuel assemblies is presented. It reveals temperature variations at the coolant inlet of the nine fuel ...
The third US Naval Observatory (USNO) CCD Astrograph Catalog, UCAC3 was released at the IAU General Assembly on 2009 August 10. It is the first all-sky release in this series and contains just over 100 million objects, about 95 million of them with proper motions, covering about R = 8 to 16 magnitudes. Current epoch positions are obtained from the observations with the 20 cm aperture USNO Astrograph's "red lens", equipped with a 4k by 4k CCD. Proper motions are derived by combining these observations with over 140 ground- and space-based catalogs, including Hipparcos/Tycho and the AC2000.2, as well as unpublished measures of over 5000 plates from other astrographs. For most of the faint stars in the Southern Hemisphere the Yale/San Juan first epoch plates from the SPM program (YSJ1) form the basis for proper motions. These data are supplemented by all-sky Schmidt plate survey astrometry and photometry obtained from the ...
Indirect evaporative air coolers that use air-to-air plate-type heat exchangers show good promise (compared with compression air-conditioning systems) of extending the energy savings from arid, low-humidity areas to more widespread climatic conditions. However, no systematic experiment had been done concerning the effect of the wettability of aluminum plates on the effectiveness of the indirect evaporative cooling system. In this study, a testing apparatus was built where only one secondary channel and two primary channels were used so that different surfaces could be easily tested to determine the system`s effectiveness and the heat transfer coefficient. The advantage of this experimental apparatus is that plates of the heat exchanger can be easily changed in the test section instead of fabricating a complete heat exchanger for each test. A dynamic contact analyzer was used to quantitatively measure the wetting properties ...
We discuss the possibility of extending solid state laser technology to high average power and of improving the efficiency of such lasers sufficiently to make them reasonable candidates for a number of demanding applications. A variety of new design concepts, materials, and techniques have emerged over the past decade that, collectively, suggest that the traditional technical limitations on power (a few hundred watts or less) and efficiency (less than 1%) can be removed. The core idea is configuring the laser medium in relatively thin, large-area plates, rather than using the traditional low-aspect-ratio rods or blocks. This presents a large surface area for cooling, and assures that deposited heat is relatively close to a cooled surface. It also minimizes the laser volume distorted by edge effects. The feasibility of such configurations is supported by recent developments in materials, fabrication processes, and optical pumps. Two types of lasers can, in ...
An ignition device of the plasma jet type is disclosed. The device has a cylindrical cavity formed in insulating material with an electrode at one end. The other end of the cylindrical cavity is closed by a metal plate with a small orifice in the center which plate serves as a second electrode. An arc jumping between the first electrode and the orifice plate causes the formation of a highly-ionized plasma in the cavity which is ejected through the orifice into the engine cylinder area to ignite the main fuel mixture. Two improvements are disclosed to enhance the operation of the device and the length of the plasma plume. One improvement is a metal hydride ring which is inserted in the cavity next to the first electrode. During operation, the high temperature in the cavity and the highly excited nature of the plasma breaks down the metal hydride, liberating hydrogen which acts as an additional fuel to help plasma formation. ...
The main reasons of tube failures in steam generators (SG) are considered. 1.Stress corrosion craining which has 28% of SG (most of them have stainless steel tubes). 2. Corrosion loss of metal, which accounts for 24% of tubes (phosphate corrosion due to addition of PO into water). 3.Denting-peripheral pressing of tubes in the openings of the foundation plates by the corrosive products, which are formed on internal surface of drillings in the foundation plates made of carbon steel. 4.Separation of a plating layer on tube panels. 5.Dratting-corrosion. 6.Metal fatigue. A series of experiments were conducted to study the influence of material selection on tube reliability (stainless steel 304, inconel-600, mone-400, incalloy-800). The problem of increase of SG elements reliability is a complex one and can be solved by direct selection of material, proper control of water-chemical conditions and other measures of corrosion ...
A metallization scheme has been developed which allows selective plating of silicon solar cell surfaces. The system is comprised of three layers. Palladium, through the formation of palladium silicide at 300/sup 0/C in nitrogen, makes ohmic contact to the silicon surface. Nickel, plated on top of the palladium silicide layer, forms a solderable interface. Lead-tin solder on the nickel provides conductivity and allows a convenient means for interconnection of cells. To apply this metallization, three chemical plating baths are employed. Palladium is deposited with an immersion palladium solution and an electroless palladium solution, and nickel is deposited with an electroless nickel solution. Solder is applied with a molten solder dip. Extensive development work has been performed to achieve an effective immersion palladium solution formulation, leading to reproducible formation of the palladium silicide contact layer. This ...
Tarapur Atomic Power Station 3 and 4 is a 540 MWe Pressurized Heavy Water Reactor. It uses 37 - element natural Uranium dioxide (UO_2) fuel pellets encapsulated inside the cylindrical sheath and are welded to the end plate at each end. During an postulated accident in which part of the fuel bundle are exposed to very high temperature (no means of heat removal) and other are at lower temperature (coolant temperature) possibility of failure of end plate weld due of thermal stresses developed by these relative temperature cannot be ruled out. In this report an attempt is made to study behaviour of fuel bundle under different temperature loading. Modelling of 37 element fuel bundle was done in ANSYS FEM. System was analysed for various sets of temperature loading. The system was analysed for plasticity and creep as material nonlinearity. The total strain, creep strain and stress increase as the temperature increases in upper portion of fuel bundle ...
The inspection of PFR evaporator tubing, superheater and reheater tubing, and tube plate examinations, are described. Ferritic steel U tubes in the evaporator have been examined by an eddy current system operating at 400 kHz using flexible rotating probes. Surface defects as shallow as 0.1 mm can be detected and sized in the range 0.1 to 0.5 mm deep. An ultrasonic method is under development for wall thickness. Special test coil probes have been developed for examination of the type 316 stainless steel superheater and reheater tubing. Crack-life defects in the bore are detectable at approximately 10% wall thickness and 20% on the outside diameter. Tube plate examinations from the tube holes, have been conducted using eddy current probes which identify surface breaking cracks in the holes. For detecting curtain cracks between tube plate holes, ultrasonic compression wave probes have been used. (U.K.).
High-performance heat transfer augmentation methods applicable in the forced convection field of heat exchangers include a method which requires no external drive means, such as the insertion of a turbulence augmentation object into the flow passage and the use of a wave-shaped flow passage, but disturbs the main stream of flow to raise the heat transportation effect thereby to augment heat transfer in the flow passage. The heat transfer characteristics and thermal performance ratio achieved when sinusoidal-shape plates are inserted instead of augmentation objects, such as cylinders, with a high shape-induced resistance were studied. As a result, the relationship between the resistance coefficient, average Nusselt number, heat transfer coefficient, and pitch was clarified. It has been revealed that the use of eddies with a large gap flow and recirculation area should be considered in order to get a higher heat transfer coefficient and a higher thermal performance ...
Nitridation of Cr-bearing alloys can yield low interfacial contact resistance (ICR), electrically conductive and corrosion-resistant CrN or Cr{sub 2}N base surfaces of interest for a range of electrochemical devices, including fuel cells, batteries, and sensors. This paper presents results of exploratory studies of the nitridation of commercially available, high Cr (30-35 wt%) Ni-Cr alloys and a ferritic high Cr (29 wt%) stainless steel for proton exchange membrane fuel cell (PEMFC) bipolar plates. A high degree of corrosion resistance in sulfuric acid solutions designed to simulate bipolar plate conditions and low ICR values were achieved. Oxygen impurities in the nitriding environment were observed to play a significant role in the nitrided surface structures that formed, with detrimental effects for the Ni-Cr base alloys, but beneficial effects for the stainless steel alloy. Positive results from single-cell fuel cell testing are also ...
Nitridation of Cr-bearing alloys can yield low interfacial contact resistance (ICR), electrically- conductive and corrosion-resistant CrN or Cr2N base surfaces of interest for a range of electrochemical devices, including fuel cells, batteries, and sensors. This paper presents results of exploratory studies of the nitridation of two high Cr (30-35 wt%) commercially available Ni-Cr alloys and a ferritic high Cr (29 wt.%) stainless steel for proton exchange membrane fuel cell (PEMFC) bipolar plates. A high degree of corrosion resistance in sulfuric acid solutions designed to simulate bipolar plate conditions and low ICR values were achieved via nitridation. Oxygen impurities in the nitriding environment were observed to play a significant role in the nitrided surface structures that formed, with detrimental effects for the Ni-Cr base alloys, but beneficial effects for the stainless steel alloy. Results of single-cell fuel cell testing are also ...
New comparative tests on two different types of solar collectors are presented in this paper. A standard glazed flat plate collector and an evacuated tube collector are installed in parallel and tested at the same working conditions; the evacuated collector is a direct flow through type with external compound parabolic concentrator (CPC) reflectors. Efficiency in steady-state and quasi-dynamic conditions is measured following the standard and it is compared with the input/output curves measured for the whole day. The first purpose of the present work is the comparison of results in steady-state and quasi-dynamic test methods both for flat plate and evacuated tube collectors. Besides this, the objective is to characterize and to compare the daily energy performance of these two types of collectors. An effective mean for describing and analyzing the daily performance is the so called input/output diagram, in which the collected solar energy is ...
The aim of this research is to experimentally study the efficiency of a new-design plate collector used to heat air in a new desalination humidification-dehumidification process. In fact, in such processes, the air solar collectors work at unusual experimental parameters (forced convection, elevated air humidity, high solar irradiation). At these stressed experimental conditions, few published works are available in literature. Furthermore, the comparison of the efficiency of collectors running with normal air humidity content (about 10-20 g kg{sup -1}) and air of elevated humidity (20-50 g kg{sup -1}) have not been published to our knowledge. In the present investigation, a new air solar plate collector was designed and developed for its use in a desalination process. Moreover, a characterization of such collector was performed under different experimental conditions. The effect of different parameters, namely: the solar radiation, the wind ...
Development of a high performance air heater through use of an evacuated tube cover design is described. The cover design utilizes evacuated fluorescent light tubes laid parallel in a close packed array to form an inner transparent glazing over a conventional metal absorber plate with flow behind the plate. A tempered flat glass plate was used as an outer glazing. Both clear and infrared reflective (IR) tubes were investigated. Solar transmittance tests indicate that the clear tube array has a higher transmittance than two flat sheets of low-iron glass. The IR coating produced substantial transmittance loss. Thermal conductance tests indicate that the tubes behave similar to two flat glass sheets with a vacuum in between. The IR reflective coating was only marginally effective at reducing heat conductance. Final prototype designs are presented along with collector performance estimates.
The behavior of silver and lead azides (scaly and threadlike crystals, and compacted powders) in initiation of explosive decomposition by laser pulsed radiation has been investigated. Initiation energy thresholds in irradiation at wavelengths of 1064 nm, 532 nm, 354.7 nm, 266 nm corresponding to four laser radiation harmonics have been measured. Samples both uncovered and covered with a transparent dielectric (a quartz plate) with the compressive force of up to 0.5GPa were initiated. In the transparent spectral region (the first and second laser harmonics) of the heavy metal azide matrix the effect of covering the sample surface with a plate on initiation energy threshold was insignificant, whereas, in the region of bandgap absorption (the fourth harmonic) strong dependence of the initiation threshold on whether the surface under irradiation is uncovered or covered. The results obtained have been considered with the account of the influence of ...
Two types of evacuated tube solar collectors have been operated in space heating, cooling and domestic hot water heating systems in Colorado State University Solar House I. An experimental collector from Corning Glass Works supplied heat to the system from January 1977 through February 1978, and an experimental collector from Philips Research Laboratory, Aachen, which is currently in use, has been operating since August 1978. A flat absorber plate inside a single-walled glass tube is used in the Corning design, whereas heat is conducted through a single glass wall to an external heat exchanger plate in the Philips collector. In comparison with conventional flat-plate collectors, both types show reduced heat losses and improved efficiency. For space heating and hot water supply in winter, the solar delivery efficiency of the Corning collector ranged from 49% to 60% of the incident solar energy. The portion of the space ...
Rapid corrosion of PWR steam generator carbon steel support structures and consequential denting of steam generator tubes led to considerable investigation of the mechanism of corrosion and for palliatives. The basic mechanism is now fairly well understood. Chloride present in the boiler feedwater from condenser leakage is concentrated in the support plate crevice as a result of the superheat present. This leads to the formation of a low pH acid ferrous chloride environment either through the hydrolysis of a weak base chloride such as MgCl_2 or the combined action of a neutral chloride with an oxidizing agent. Rapid attack of the carbon steel ensues with the Fe_3O_4 corrosion product forming at the metal/oxide interface. This oxide has a volume approximately twice that of the steel consumed and thus eventually fills the crevice between the tube and the support plate. Oxide growth continues leading to compression of the Alloy 600 primary tube ...
The flow distribution through a plate-fin heat exchanger is studied by using a computational fluid dynamics (CFD) code, FLUENT. The flow distribution through any heat exchanger affects its performance. In designing a heat exchanger, it is assumed that the fluid is uniformly distributed through the heat exchanger core. In practice, however, it is impossible to distribute fluid uniformly, because of an improper inlet configuration, imperfect design, and a complex heat transfer process. The CFD simulation of the flow distribution in the header of a conventional plate-fin heat exchanger is presented. It is found that the flow maldistribution is very serious in the y-direction of the header. A modified header is proposed and simulated using CFD. The modified header configuration has a more uniform flow distribution than the conventional header configuration. Hence, the efficiency of the modified heat exchanger is seen to be higher than that of the ...
This paper describes Fuji computed radiography (FCR) of Fuji Film for NDT (non-destructive testing). Imaging plate (IP) is a two-dimensional detector of X-ray, and shows higher photographic sensitivity than X-ray film. The output emission of IP provides a good linear relationship to X-ray intensity in a wide intensity range. When this emission can be digitized, the X-ray intensity can be also digitized. IP is applied to NDT as an inspection using X-ray. FCR provides higher photographic sensitivity than the conventional X-ray film method, which results in one-fifth to one-twentieth of irradiation time. Images with stable density can be obtained independent of the intensity. Since IP has a wide dynamic range, the variation of X-ray intensity of 1:500 can be expressed in a single image by single shot. High density record including 1000 images can be done using a 5.25 inch optical disk through the digital image processing and the electrical quantification. The ...
An impinging jet is a widely used technique for realizing high heat-transfer rates between a fluid and a surface. However, the area of enhanced heat transfer is limited to the neighborhood of the stagnation point. In this study, heat transfer is augmented remote from the stagnation point in an impinging plane jet system by a rod array located near the wall. Each square rod in the array was positioned normal to the flow direction and parallel to the flat plate surface. The distance between the nozzle and the flat plate (H) and the spacing between the rods and the flat plate surface (C) were changed to find the optimum values. The largest heat-transfer augmentation was obtained for C = 1 mm, H/B = 10, where the jet nozzle width is B. In this case, the heat-transfer coefficient averaged over an area 2B from the stagnation point is about 1.6 times greater compared to that without a rod array.
Hydrogen storage alloy composites La{sub 0.7}Mg{sub 0.25}Zr{sub 0.05}(Ni{sub 0.85}Co{sub 0.15}){sub 3.5}(x=0,5,10) were prepared by ball milling method. Their structures, morphologies and the hydrogen storage characteristics were intensively studied in the present work. It was found that the bulk of composites maintained the hexagonal C14 Laves phase structure after ball milling with additional La-Mg-based alloy for two hours. Scanning electron microscopy (SEM) observations revealed that the average size of Ti{sub 0.9}Zr{sub 0.2}Mn{sub 1.5}Cr{sub 0.3}V{sub 0.3} and La{sub 0.7}Mg{sub 0.25}Zr{sub 0.05}(Ni{sub 0.85}Co{sub 0.15}){sub 3.5} particles were reduced to several hundred nanometers after ball milling process. Energy dispersive X-ray spectrometer (EDS) patterns of the composites showed that the La{sub 0.7}Mg{sub 0.25}Zr{sub 0.05}(Ni{sub 0.85}Co{sub 0.15}){sub 3.5} phase was uniformly distributed on the surface of Ti{sub ...
Purpose: To enable the use of a vacuum container under a relatively high temperature or a high level radioactive dose. Constitution: Vacuum sealing materials for use in a vacuum container are made of resins such as polyimide and polyamide. The sealing materials are joined to the both surfaces of a plate-like insulator by means of adhesives or sealants, or the sealing materials are joined between two plate-like insulators by means of adhesives or sealants. They are situated within grooves of both of flanges, which are clamped tightly by insulation bolt and nut. Since the vacuum sealing materials are joined to the insulator by means of the adhesives or sealants, the reliability of the vacuum sealing can be improved without impairing the electrical insulation. The resin of the vacuum sealing material can be used for the radiation dose up to 10"8 rad, temperature up to 250"0C or more. (Seki, K.).
The use of primary electron counting techniques as an alternative to the more usual parallel plate avalanche chamber that has been employed in soft x-ray scattering experiments is being investigated at the National Synchrotron Light Source. The theoretical aspects of primary electron counting and motivation behind building a primary electron counting detector are described, as well as characteristics and future improvements of the device constructed at the NSLS. The detector consists of a low electric field drift region and a low pressure multistep avalanche region which can be operated with two or three stages of electron multiplication. The device has worked well in extensive tests as a simple parallel plate avalanche chamber, providing energy resolutions of 58% and 43% at 277 and 500 eV, respectively. Operated as a primary electron counter, preliminary results show an energy resolution of 38% at 500 eV.
The unsteady two-dimensional laminar flow of a viscous incompressible electrically conducting micro polar fluid via a porous medium past a semi-infinite vertical porous moving plate in the presence of a transverse magnetic field is studied. A uniform magnetic field acts perpendicularly to the porous surface in which absorbs the micro polar fluid with a suction velocity varying with time. The effects of material parameters on the velocity and temperature fields across the boundary layer are investigated. The method of solution can be applied for small perturbation approximation. Numerical results of velocity and temperature distributions of micro polar fluids are compared with the corresponding flow problems for a Newtonian fluid. (author)
The studies using phantoms confirmed that the reduction of electron beam energy and minimization of X-ray contamination could be achieved when electron beam was interposed by an acrylic plate placed 20 cm anterior to a patient. Four patients of mycosis fungoides were treated with 8 MeV electron beam of a linear accelerator at UOEH Hospital from October 1981 to December 1986. Two of them were treated with this technique by placing 2 cm thick acrylic plate anterior to the patients and satisfactory results were obtained. Cutaneous lesions subsided remarkably with the dosage of 2000 cGy given in 2 months. Leucopenia due to bone marrow suppression was mild and the patients tolerated the treatment well.
The studies using phantoms confirmed that the reduction of electron beam energy and minimization of X-ray contamination could be achieved when electron beam was interposed by an acrylic plate placed 20 cm anterior to a patient. Four patients of mycosis fungoides were treated with 8 MeV electron beam of a linear accelerator at UOEH Hospital from October 1981 to December 1986. Two of them were treated with this technique by placing 2 cm thick acrylic plate anterior to the patients and satisfactory results were obtained. Cutaneous lesions subsided remarkably with the dosage of 2000 cGy given in 2 months. Leucopenia due to bone marrow suppression was mild and the patients tolerated the treatment well. (author).
The antimicrobial activity of simulated solar disinfection (SODIS) in the presence and absence of riboflavin against various protozoa and helminth organisms was investigated in this study. Assays were conducted in transparent 12 well microtitre plates containing a suspension of test organisms in the presence or absence of 250mM riboflavin. Plates were exposed to simulated sunlight at an optical irradiance of 550Wm^-^2 (watts per square metre) delivered from a SUNTEST(TM) CPS+ solar simulator. Aliquots of the test suspensions were taken at set time points and the viability of the test organisms was determined by either culture, microscopy or flow cytometry where applicable. With Acanthamoeba, Naegleria, Entamoeba and Giardia exposure to SODIS at an optical irradiance of 550Wm^-^2 for up to ...
Abstract in english Numerical solutions for the effects of radiation on a MHD convective heat transfer past a semi-infinite porous plate with a magnetic field are obtained. It is assumed that the porous plate moves with a constant velocity in the direction of fluid flow, and the free stream velocity follows the exponentially increasing small perturbation law. The magnetic field acts perpendicular to the porous surface which absorbs the fluid with a suction velocity varying with time. The gov (more) erning equations for the flow are transformed into a system of nonlinear ordinary differential equations by perturbation technique and then are solved numerically by using the shooting method. The effects of the various parameters on the velocity, temperature profiles as well as the surface skin-friction and surface heat transfer are illustrated graphically.
Until a decade ago, only the differential bobbin type eddy current probe was considered necessary for reliable heat exchanger tube inspection. The introduction of different tube materials, manufacturing processes and a variety of service induced failures has greatly increased the demands of eddy current testing. Optimized probe designs enhanced by improved instrumentation can help satisfy some of these demands. Some of the more difficult inspection problems are detection of circumferential cracks, fretting wear under non-ferromagnetic support plates and shallow internal defects. Reliable detection and sizing of such defects is often made more difficult by the fact they frequently occur in defect prone regions such as under tubesheets or support plates and in transition regions of finned tubes. Probe designs effective in overcoming these difficulties exist. This paper describes a number of such probes and their performance.
The paper discusses the aspects of repair and retrofitting technique adopted for a damaged reinforced concrete beam-column joint specimen under cyclic loading. A specimen designed based on Indian Standard specifications with consideration of seismic load but without adopting ductile detailing (NonDuctile) was investigated under reverse cyclic loading. Then, the damaged nonductile specimen was repaired with epoxy mortar and grouted using low viscous polymer, and retrofitted using fiber reinforced plastic (FRP) wrapping in beam and column components and steel plate jacketing in joint region. The experimental results showed that the retrofitted specimen not only regained its original strength and stiffness but also has overcome the deficiencies of nonductile detailing. The present study shows...
In this paper, a novel type of a corona discharge plasma reactor was designed, which consists of needle-plate-combined electrodes, in which a series of needle electrodes are placed in a glass container filled with flue gas, and a plate electrode is immersed in the water. Based on this model, the removal of NO and SO2 was tested experimentally. In addition, the effect of streamer polarity on the reduction of SO2 and NO was investigated in detail. The experimental results show that the corona wind formed between the high-voltage needle electrode and the water by corona discharge enhances the cleaning efficiency of the flue gas because of the presence of water, and the cleaning efficiency will increase with the increase of applied dc voltage within a definite range. The removal efficiency of SO2 up to 98%, and about 85% of NOx removal under suitable conditions is obtained in our experiments.
We describe a position sensitive photon counting microchannel plate based detector with an improved quadrant anode (QA) readout system. The technique relies on a combination of the four planar elements pattern and an additional fifth electrode. The charge cloud induced by single particle detection is split between the electrodes. The measured charge values uniquely define the position of the initial event. QA has been first published in 1976 by Lampton and Malina. This anode configuration was undeservedly forgotten and its potential has been hardly underestimated. The presented approach extends the operating spatial range to the whole sensitive area of the microchannel plate surface and demonstrates good linearity over the field of view. Therefore, the novel image sensor results in spatial resolution better then 50?m and count rates up to one million events per second.
We describe a position sensitive photon counting microchannel plate based detector with an improved quadrant anode (QA) readout system. The technique relies on a combination of the four planar elements pattern and an additional fifth electrode. The charge cloud induced by single particle detection is split between the electrodes. The measured charge values uniquely define the position of the initial event. QA has been first published in 1976 by Lampton and Malina. This anode configuration was undeservedly forgotten and its potential has been hardly underestimated. The presented approach extends the operating spatial range to the whole sensitive area of the microchannel plate surface and demonstrates good linearity over the field of view. Therefore, the novel image sensor results in spatial...
A position-sensitive event-counting electronic readout system for microchannel plates (MCPs) is described that offers the advantages of high spatial resolution and fast time resolution. The technique relies upon a four-quadrant electron-collecting anode located behind the output face of the microchannel plate, so that the electron cloud from each detected event is partly intercepted by each of the four quadrants. The relative amounts of charge collected by each quadrant depend on event position, permitting each event to be localized with two ratio circuits. A prototype quadrant anode system for ion, electron, and extreme ultraviolet imaging is described. The spatial resolution achieved, approx. =10 ..mu.., allows individual MCP channels to be distinguished. (AIP)
A position-sensitive event-counting electronic readout system for microchannel plates (MCPs) is described that offers the advantages of high spatial resolution and fast time resolution. The technique relies upon a four-quadrant electron-collecting anode located behind the output face of the microchannel plate, so that the electron cloud from each detected event is partly intercepted by each of the four quadrants. The relative amounts of charge collected by each quadrant depend on event position, permitting each event to be localized with two ratio circuits. A prototype quadrant anode system for ion, electron, and extreme ultraviolet imaging is described. The spatial resolution achieved, approx. =10 #mu#, allows individual MCP channels to be distinguished.
Plasma nitriding was applied to improve the surface performance of titanium bipolar plate. XRD and SEM results showed a titanium nitride layer was formed after nitridation. In comparison with pure titanium, the interfacial contact resistance of plasma nitrided titanium was reduced to some extent by the nitridation treatment. However, high corrosion current was observed under electrochemical tests in 0.5 M H{sub 2}SO{sub 4} + 5 ppm HF. Both the electrical conductivity and corrosion resistance of the surface of plasma nitriding titanium did not reach the level of graphite. Some more improvements are expected in the plasma nitriding process or another surface modification on pure titanium. (author)
A time-of-flight (TOF) spectrometer has been constructed at the JAERI 20 MV tandem accelerator facility. A position-sensitive start detector, which consists of a thin carbon foil, microchannel plates and a resistive plate, was developed for the TOF measurements through the spectrometer. The time and position resolutions obtained were 120 ps and 0.3 mm for ..cap alpha.. particles from /sup 241/Am, respectively. A two-dimensional position-sensitive detector was also developed to measure the solid angle of the spectrometer and the maximum solid angle obtained was 9.5 msr. As a particle detector a Bragg curve ionization chamber was developed. From the Bragg curves of heavy ions in the detector, energies, ranges and Bragg curve peaks were measured and used for particle identification. The resolving power Z/..delta..Z of the atomic number was about 50.
A set of nomographs to estimate the levelized energy cost for photovoltaic systems are presented. These are designed to assist system designers, analysts, and planners in estimating the effects of research and development and system-design optimization on the delivered cost of energy. The nomographs are based on a refined version of the energy cost estimation equation that appears in the National Photovoltaics Program Five-Year Research Plan. The nomographs have been prepared to emphasize technologies with the potential of producing low-cost energy (<$0.40/kWh levelized in nominal terms or $0.17/kWh in 1982 dollars), and thus primarily apply to far-term or advanced intermediate photovoltaic technologies. Separate sets of nomographs are presented to encompass both flat-plate and concentrator technologies. To supplement the nomographs, a set of tabular solutions of the energy cost equation are included as an appendix.
The effects of thermal radiation and viscous dissipation on magneto-hydrodynamic (MHD) unsteady free-convection flow over a semi-infinite vertical porous plate are analysed. The fluid considered is non-gray (absorption coefficient dependent on wave length). The Network Simulation Method is used to solve the boundary-layer equations based on the finite-difference formulation; only discretization of the spatial co-ordinates is necessary, while time remains as a real continuous variable. This method provides a solution for both transient and steady-state problems at the same time, and programming does not require manipulation of the sophisticated mathematical software that is inherent in other numerical methods. The velocity, temperature, local skin-friction and local Nusselt number are studi...
A new chemical reactor, the Open Plate Reactor, is being developed by Alfa Laval AB. It combines good mixing with high heat transfer capacity into one operation. With the new concept, highly exothermic reactions can be produced using more concentrated reactants. A nonlinear model of the reactor is derived and a control system is developed. For temperature control a cooling system is designed and experimentally verified, which uses a mid-ranging control structure to increase the operating range of the hydraulic equipment. A Model Predictive Controller is proposed to maximize the conversion under hard input and state constraints. An extended Kalman filter is designed to estimate unmeasured concentrations and parameters. Simulations show that the designed control system gives high conversion ...
In Polymer Electrolyte Fuel Cell (PEFC) technology the reducing of volume and mass of the fuel cell stack and the improvement of catalyst utilization are of great interest. These parameters affect applicability and system cost. In this work we present an alternative way for reducing the stack volume by combining gas distribution and catalytic active area in one plate. Micro machined glassy carbon electrodes serve as support material for the platinum catalyst, as well as gas distributor at the same time. A comparison of these electrodes with conventional platinum-black gas diffusion electrodes under fuel cell conditions shows that the new system is a promising electrode type for enhanced power density and catalyst utilization. (author) 3 figs., 5 refs.
A new luminescent europium probe is presented for the determination of phosphate (P) in microtiter plate format. The assay is based on the quenching of the luminescence of the europium-tetracycline (EuTc) 1:1 complex by phosphate using a reagent concentration of 20.8 {mu}mol/L. The probe is excited at 400 nm and displays a large Stokes' shift of 210 nm. The emission maximum is located at 616 nm. The system works best at neutral pH 7 and is therefore suitable for phosphate determination in biological and biochemical systems. The linear range of the calibration plot is from 5 x 10{sup -6} mol/L to 7.5 x 10{sup -4} mol/L of phosphate, and the limit of detection is 3 {mu}mol/L.
A proposed metallization system for large area silicon solar cells with shallow junctions is outlined, and its desirable features are discussed. A baseline process sequence for the nickel palladium metallization system (NPMS) is delineated. This baseline process sequence is serving as the starting point from which process variations are being performed. The eventual goal is optimization of the NPMS process and determination of the control ranges for NPMS process variables. Initial studies of palladium displacement and electroless chemical plating solutions used in the baseline NPMS have begun and progress is reported. In support of this work, an annotated bibliography (45 citations) dealing primarily with palladium plating and palladium-silicon contact formation has been prepared (and will be subject to updating in the future reports).
A numerical investigation for forced convection in a constant-temperature parallel plate channel with porous cavity and block alternately emplaced on the bottom plate is presented in this work. The Brinkman-Forchheimer-extended Darcy model, which accounts for the effects of impermeable boundary and inertia, is used to characterize the flow field inside the porous region. Solutions of the coupled governing equations are carried out through the stream function-vorticity analysis. The characteristics of fluid flow and forced convection heat transfer have been obtained by the examinations of various governing parameters, such as the Reynolds number, Darcy number, inertial parameter, Prandtl number, and two geometric parameters. Several interesting phenomena such as the heat transfer augmentation in the channel were presented and discussed. The results of this investigation indicate that the size of recirculation caused by porous block will have a ...
As part of Steam Generators Owners Group Project S-146, ''Diffusion and Hideout in Crevices,'' experimental data were obtained on chloride salt hideout and return in a controlled-boiling INCON system containing three electrically heated, thermocouple instrumented tube-to-support-plate intersections. The support plate simulants had first been caused to undergo, in situ, denting-type corrosion to the extent that substantial tube deformation was observed. Then chloride hideout and return measurements were made, using sodium chloride as the impurity additive. Experimental results were fitted to an elementary model for the crevice and its associated transport processes. Details on the experimental work and a description of the data-fitting method are given in the final report, NP-2979, dated March 1983.
In this study we discuss an unsteady free convection MHD flow past semi-infinite vertical porous plate. We have considered the flow in the presence of a strong magnetic field and therefore the electromagnetic force is very large. This brings in the phenomenon of Hall and Ion-slip currents. The effects of these two parameters together with that of viscous dissipation and radiation absorption among others on velocity, temperature and concentration profiles are presented. The profiles are presented graphically. As the partial differential equations governing this problem are highly non-linear they are solved numerically by a finite difference method. It is found that in presence of heating of the plate by free convection current the velocity boundary layer thickness decreases.
In this study we discuss an unsteady free convection MHD flow past semi-infinite vertical porous plate. We have considered the flow in the presence of a strong magnetic field and therefore the electromagnetic force is very large. This brings in the phenomenon of Hall and Ion-slip currents. The effects of these two parameters together with that of viscous dissipation and radiation absorption among others on velocity, temperature and concentration profiles are presented. The profiles are presented graphically. As the partial differential equations governing this problem are highly non-linear they are solved numerically by a finite difference method. It is found that in presence of heating of the plate by free convection current the velocity boundary layer thickness decreases.
The purpose of this paper is to check up a GPS (global positioning system) impact on scientific research activities of the Geodetic Society of Japan. First, it is mentioned that the conventional geoid-based concept of 'gravity anomaly' should be changed to a new definition, according to the GPS-determined ellipsoidal height system. Secondly, the results of many experiments, which have been made to monitor ocean-plate motions relative to the Japanese island-arcs, demonstrate that GPS is a powerful tool for obtaining temporal changes in horizontal displacement induced by the plate motion. Therefore, it is suggested that terrestrial measurements, such as triangulation and long-range leveling, would be replaced by GPS measurements in near future. Moreover, it is pointed out that GPS geodesy should play an important role in monitoring secular sea level trend due to global warming of the atmosphere and ocean. 19 refs., 4 figs.
Fuji computed radiography (FCR) utilizing imaging plates stimulated by a scanning lazer has been developed in Japan and come to be widely available in diagnostic radiology. This system is advantageous because many processed images can be obtained with a single exposure. However, no reports have been published on the exact conditions necessary under which the FCR image processing method will produce improved visibility of pulmonary abnormal shadows on chest radiographs. In this report, chest FCR images obtained from 50 patients were analyzed, and the best practical image processing conditions were determined for each pathological state. Fundamental analysis was also performed for spatial and contrast resolution with FUNK chart and Burger's phantom using various thickness of acryl plate. Ninety processing images per exposure were analyzed, and the best practical conditions were determined. (author).
Fuji computed radiography (FCR) utilizing imaging plates stimulated by a scanning lazer has been developed in Japan and come to be widely available in diagnostic radiology. This system is advantageous because many processed images can be obtained with a single exposure. However, no reports have been published on the exact conditions necessary under which the FCR image processing method will produce improved visibility of pulmonary abnormal shadows on chest radiographs. In this report, chest FCR images obtained from 50 patients were analyzed, and the best practical image processing conditions were determined for each pathological state. Fundamental analysis was also performed for spatial and contrast resolution with FUNK chart and Burger's phantom using various thickness of acryl plate. Ninety processing images per exposure were analyzed, and the best practical conditions were determined. (author).
The CO laser is superior in the absorption characteristic to materials to the CO2 laser due to its shorter wavelength. In consideration of this characteristic Nuclear Power Engineering Corporation is studying this applicability sponsored by the Ministry of International Trade Industry of Japan to cutting of reactor core internals of commercial nuclear power plant. In decommissioning of reactor core internals it is necessary to cut stainless steel plates of 305 mm thick. The authors cut stainless steel plates of up to 310mm thick in air and those of up to 150 mm thick underwater with a 20kW class laser. Further, models simulating key structural elements of PWR core internals were cut and secondary products to clarify the applicability of the CO laser cutting to reactor core internals were evaluated. (author)
A six-axis active vibration isolation system (AVIS) is designed by using the direct driven guide and ball contact mechanisms in order to have no cross-coupling between actuators. The point contact configuration gives an advantage of having an easy assembly of eight voice coil actuators to an upper and a base plate. A voice coil actuator is used since it can provide a large displacement and sufficient bandwidth required for vibration control. The AVIS is controlled considering the effect of flexible vibration mode in the upper plate and velocity sensor dynamics. A loop shaping technique and phase margin condition are applied to design a vibration controller. The performances of the AVIS are investigated in the frequency domain and finally validated by comparing with the passive isolation system. The scanning profiles of the specimen are compared together by using the atomic force microscope. The robustness of the AVIS is verified by showing the ...
Purpose: To prevent structure material meltdown upon rupture of cooling pipeways in a impurity remover by preventing the coolants from flowing into the vacuum vessel while continuing the supply of coolants to other portions to be cooled. Constitution: Dual cooling pipeway systems are disposed to the neutralizing plates of the impurity remover. A rupture detector (pressure gage) is mounted to each of the cooling pipeways and flow rate control valves to be opened and closed by the signal from the detector are disposed to the upstream and downstream of the cooling pipeway. In this constitution if the cooling pipes should be ruptured, the coolant supply is stopped to the ruptured system in which the flow rate valve is closed by the signal from the rupture detector. However, since the coolant is kept to be supplied to the other system of the cooling pipeways, meltdown of the neutralizing plates can be prevented. (Kamimura, M.).
Direct plating, selective enrichment, and cold enrichment followed by secondary selective enrichment procedures were compared for detecting and enumerating Listeria monocytogenes in chopped cabbage stored at 5 degrees C for up to 64 days. Addition of Fe3+ to solid media enhanced detection of the organism. Cold enrichment (5 degrees C) in nutrient broth and brain heart infusion broth followed by secondary enrichment (48 h, 30 degrees C) in Trypticase soy-yeast extract-antibiotic broth and thiocyanate-nalidixic acid broth and plating on selective agar media (Doyle and Schoeni selective enrichment agar [minus acriflavin hydrochloride, supplemented with 5 micrograms of Fe3+/ml] and McBride Listeria agar) resulted in the detection of highest populations. PMID:3111369
By using a charge-sensitive preamplifier and methods of energy spectroscopy we investigated the response of a parallel plate avalanche counter in order to scan the Bragg curve. The detector was operated in butane, pentane and heptane which also served as stopping gases. In this paper, we report on results obtained with fission fragments from a /sup 252/Cf source. We achieved a separation of the light and heavy fragment groups in the interval of gas absorber thickness from about 500 ..mu..g cm/sup 2/ to 1.5 mg cm/sup 2/. The best energy loss resolution was achieved with pentane at E/papprox.=70 V cm/sup 1/ Torr/sup 1/ resulting in delta..delta..E/..delta..Eapprox.=13%. The corresponding shape of the ..delta..E spectrum reproduces correctly the nuclear charge distribution of the fragments. (orig.).
Investigatins into the welding of alloy 800 at the Reactor Fuel Element Laboratories, Springfields, commenced about three years ago following an extended development programme on tube to tube plate welding of low alloy and stainless steels for the Prototype Fast Reactor. The techniques and approach developed for critical fuel element welding applications had proved equally suitable for the precision welding requirements on the much heavier sections of heat exchangers. It had been demonstrated that the same control of weld quality and profile could be achieved with consistency and the permissible range of critical parameters could be readily defined. Because of this, development work was continued to include other materials, such as alloy 800, which might be of potential use. The tungsten inert gas (T.I.G.) arc welding process is used, and the equipment, including the control system, is described. Tube to tube-plate welding, and tube to tube ...
This study is concerned to the perforation phenomena of the oblique dual-plate by projectile. Experiment and simulation related to that was carried out. the variables considered in this phenomena include the electrolytic zinc coated steel sheet and carbon steel rod. In the former, the confirmation and projectile velocity possible phenomena of real phenomena is done, the latter, the effect of parameter such as time-step and grid space length is analyzed by using the three-dimensional Lagrangian explicit time-integration finite element code, HEMP. This code use the eight node hexahedral elements and in this study, Von-Mises Criteria is used as the strength model, Mie-Gruneisen is as the Equation of State. The simulation was performed by contrast with the experiment. Through the calibration of the parameter of Lagrangian code, reasonable result was approached.
In this paper, the unsteady MHD free convection heat and mass transfer of viscous fluid flowing through a Darcian porous regime adjacent to a moving vertical semi-infinite plate under Soret and Dufour effect have been examined. Viscous dissipation effects are included in the energy equation. A uniform magnetic field is applied transversely to the direction of the flow. The differential equations governing the problem have been transformed by a similarity transformation into a system of non-dimensional differential equations which are solved numerically by element free Galerkin method. The influence of Grashof number (Gr), magnetic parameter (M), heat absorption parameter (Q), permeability parameter (K), Schmidt number (Sc), Soret number (Sr), and Dufour number (Du) on the velocity, tempera...
For charged particle irradiations, the response of an imaging plate (IP) changes around the Bragg peak. Therefore, an appropriate compensation is necessary for the evaluation of dose distribution formed by charged particles such as protons. In this paper, the response of IPs to clinical proton beams is investigated. An experimentally-obtained depth-dose distribution (an ordinary Bragg curve) by a silicon semiconductor detector (SSD) is employed to evaluate the compensation factors as a function of proton penetrating depth, i.e. residual range. A typical dose distribution in a water phantom formed by an L-shaped bolus is measured by IPs and corrected by using the information of those compensation factors; the residual proton range is successfully calculated by the pencil beam algorithm at an arbitrary point. The results show a good agreement with the measurements by the SSD within the rms error of 3.0%.
The water and steam circuits of steam generators in pressurized-water nuclear power plants are described together with the mechanism of denting, and the corrosion of spacer plates that leads to cracks in tubes by constriction. The different chemical specifications applicable to the water of the secondary circuit of the generators in normal operation and on first commissioning are listed. The results obtained and the measurements of chemical values taken in operation on the water in the secondary circuits of steam generators at Fessenheim and Bugey are presented.
The water and steam circuits of steam generators in pressurized-water nuclear power plants are described together with the mechanism of denting, and the corrosion of spacer plates that leads to cracks in tubes by constriction. The different chemical specifications applicable to the water of the secondary circuit of the generators in normal operation and on first commissioning are listed. The results obtained and the measurements of chemical values taken in operation on the water in the secondary circuits of steam generators at Fessenheim and Bugey are presented.
Aerobic chemoheterotrophic bacteria were isolated from surface soils and coastal plain subsurface (including deep aquifer) sediments (depths to 265 m) at a study site near Aiken, S.C., by plating on...Full Text Available
We propose a scheme with potential experimental realization to generate 'polarization' entanglement between two atomic ensembles and show one of the applications - a novel secure communication allowing asymptotically key distribution and quasisecure direct communication. The scheme involves laser manipulation of atomic ensembles, adjustable quarter- and half-wave plates, beam splitters, polarizing beam splitters and single-photon detectors, and well fits the status of the current experimental technology.
Esters of dihydric alcohols with alkenylphosphonic or alkenylphosphinic acids which are polymerizable by free radicals are described. They are combined with polymer binders, in particular water-soluble polymers, and photoinitiators forming free radicals to give photopolymerizable mixtures which are suitable for the production of photoresists and printing plates. The mixtures display low heat-sensitivity and have long shelf lives. (author) 1 tab.
Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni-Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitride (CrN and Cr{sub 2}N) surface layer through nitridation of Fe-base stainless steel alloys. The key to form a protective Cr-nitride surface layer was found to be the initial formation of oxide during nitridation, which prevented the internal nitridation typically observed ...
Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni-Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitride (CrN and Cr{sub 2}N) surface layer through nitridation of Fe-base stainless steel alloys. The key to form a protective Cr-nitride surface layer was found to be the initial formation of oxide during nitridation, which prevented the internal nitridation typically observed ...
The observed strength of the carbon dioxide absorption bands recorded on spectrobolograms of the transparency of the earth's atmosphere between wavelengths 300 and 2500 nanometers as part of the Smithsonian Solar Constant Program were used to extract the abundance of carbon dioxide in the atmosphere. The details of the analysis and the sources of error are discussed. 11 references, 5 figures, 1 table. (ACR)
Thermal (gas) nitridation of stainless steel alloys can yield low interfacial contact resistance (ICR), electrically conductive and corrosion-resistant nitride containing surface layers (Cr{sub 2}N, CrN, TiN, V{sub 2}N, VN, etc.) of interest for fuel cells, batteries, and sensors. This paper presents results of scale-up studies to determine the feasibility of extending the nitridation approach to thin 0.1 mm stainless steel alloy foils for proton exchange membrane fuel cell (PEMFC) bipolar plates. Developmental Fe-20Cr-4V alloy and type 2205 stainless steel foils were treated by pre-oxidation and nitridation to form low-ICR, corrosion-resistant surfaces. As-treated Fe-20Cr-4V foil exhibited target (low) ICR values, whereas 2205 foil suffered from run-to-run variation in ICR values, ranging up to 2 x the target value. Pre-oxidized and nitrided surface structure examination revealed surface-through-layer-thickness V-nitride particles for the treated Fe-20Cr-4V, but ...
Thermal (gas) nitridation of stainless steels can yield low interfacial contact resistance (ICR), electrically-conductive and corrosion-resistant nitride containing surfaces (Cr2N, CrN, TiN, V2N, VN, etc) of interest for fuel cells, batteries, and sensors. This paper presents the results of scale up studies to determine the feasibility of extending the nitridation approach to thin 0.1 mm stainless steel alloy foils for proton exchange membrane fuel cell (PEMFC) bipolar plates. A major emphasis was placed on selection of alloy foil composition and nitidation conditions potentially capable of meeting the stringent cost goals for automotive PEMFC applications. Developmental Fe-20Cr-4V alloy and type 2205 stainless steel foils were treated by pre-oxidation and nitridation to form low-ICR, corrosion-resistant surfaces. Promising behavior was observed under simulated aggressive anode- and cathode- side bipolar plate conditions for both materials. ...
Some of the origins of corrosion encountered in the secondary side of pressurized water reactor steam generators are:-sludge accumulation (a mixture of metal oxides, primarily magnetite and copper) on tube sheet and attack of tube support plates by aggressive impurities leading to denting. Although Electricite de France has not suffered from these problems, it has developed a chemical cleaning process to dissolve corrosion products at both locations. (author).
This paper presents a numerical investigation of laminar flows and heat transfer in a horizontal rectangular channel whose top and bottom plates have been punched out in the form of a delta wing. The flow structure with respect to the generation, transport, and stability of vortices in laminar horizontal channel flows with combined forced and free convection are reported. To include free convection, Boussinesq approximation of the buoyancy is used and the flow medium is treated as incompressible.
Magnetic resonance imaging can be used in the trauma setting to detect fractures and associated soft tissue injuries of the musculoskeletal system. Magnetic resonance imaging complements plain radiography and CT for evaluating cancellous bone, cartilage and growth-plate injuries, and intra- and extraarticular supporting soft tissue structures. This review outlines typical applications and imaging consideration for injuries of the pelvis and lower extremity. (orig.) With 12 figs., 78 refs.
Computed radiography (CR) systems use a photostimulable phosphor plate enclosed in a cassette. In CR, image acquisition is a two-stage process wherein image capture and image read out are done separately. Direct digital radiography (DR) systems, on the other hand, use detectors that have a combined image capture and image read out capability. DR systems are also called as DDR or ddR systems by some vendors. This article focuses on DR systems
A three-dimensional steady numerical computation was made for a component model of fin and tube type of compact heat exchangers situated in a uniform flow. In this study, in order to find a clue to design high-efficient heat exchangers, numerical computation was made in the case where two fences are attached on the plate fin surface and their geometrical effects such as their locations, their heights and their attack angles on flow and heat transfer characteristics were investigated especially in the low Reynolds number range. The effect of a hole, open in the plate fin behind the fence, on heat transfer and flow structures was also examined. This hole simulates the hole of the plate fin to be produced in practical application, when a fence is produced by punching from the original plain fin plate. Two fences with holes were found to show several important effects on flow and heat transfer structures ...
Solids are separated from a liquid in a gravity settler provided with inclined solid intercepting surfaces to intercept the solid settling path to coalesce the solids and increase the settling rate. The intercepting surfaces are inverted V-shaped plates, each formed from first and second downwardly inclined upwardly curved intersecting conical sections having their apices at the vessel wall.
A 5 V glassy carbon capacitor stack was built consisting of four bipolar and two end-plate electrodes. More than 100,000 charging/discharging cycles were applied to test the stability of the double-layer capacitor. Low and high frequency resistances were measured as a function of the number of cycles. (author) 2 figs., 1 ref.
The successful installation of the Europipe 16/11E Riser jacket in July 1994 and the coming installation of Sleipner T jacket in spring 1996 proves that suction installed skirted plate foundations (buckets), may not only be a competitive alternative to piles, but also a complementary foundation solution both for noncohesive and cohesive soils. This paper presents the background for the design analyses of the Europipe 16/11E and Sleipner T foundations in terms of the performed field and model tests, as well as the theoretical models and practical analysis tools utilized for design.
This report highlights the significance of the geological sciences to the nation and to society. Discussions include understanding plate tectonics and surface processes, exploring the continental crust, ocean basins and the deep earth, applications of geology to social problems such as mineral resources, waste disposal, siting of critical facilities, geological hazards, water resources management, and coastal zones. The state of health of geological research is also discussed. (ACR)
Since April, 1985, we have, in co-operation with the Fuji Film Co., Ltd., used Fuji Computed Radiography (FCR) in the diagnosis of spinal disorders. FCR is a new computed radiographic system which uses an energy-storage phosphorus panel called an ''Imaging Plate'' as an image sensor. The ''Imaging Plate'' can be used to obtain radiographs in exactly the same way as the screen-film combination used in conventional radiography; X-rays are exposed on the ''Imaging Plate'' instead of X-ray film in the conventional fashion, and then the ''Imaging Plate'' is calculated. The processed digital data from the scans is transformed into a picture by means of digital-to-analogue conversion. The pictures are always clear and beautiful. Plain films of the spine taken by FCR ...
In this report, the quantitative relation between the height equivalent to a theoretical plate (HETP) and the size of ion exchange resin is studied by enriching lithium isotopes with high pressure ion exchange displacement chromatography. The dependence of HETP on the size of the resin can be expressed as H = C x (anti r)sup( ) in which = 2.4 and it is found that Snyder's equation is suitable for such a system of isotope separation as may be explained by the simple displacement mechanism.
The steam generator (SG) is one of the most critical components of the heat transfer system in nuclear generation stations. Testing the structural integrity of SG tubing and SG internals is a key element of the fitness-for-service assessments to assure the safe and continuous operation of nuclear power plants. Recent eddy current (ET) inspections of two nuclear power plants revealed degradation of some of the tube support plate (TSP) structures, which was also confirmed by visual inspection. The phenomena was described as metal loss, caused by flow-accelerated corrosion of the carbon steel trefoil support plate and varying from minor to complete loss of the ligaments. This loss of TSP ligaments results in lack of support for the adjacent tubes making them more susceptible to fretting-wear damage and fatigue cracking. A signal analysis method, based on the responses at low frequency of two types of eddy current probes, has been developed to ...
In the paper, a potential of solar energy for drying of medicinal plants in Polish conditions is estimated and development of solar drying technologies is presented. The results of economic assessment of flat-plate solar collectors applied for drying of medicinal plants on a farm are promising. In some specific conditions, e.g. drying of wild grown medicinal plants in remote areas, even application of photovoltaic modules for driving of a fan of a solar dryer is a profitable option and enables easy control of the drying air temperature.
The Doublet III device is operating with an extensive system of plasma limiters and wall protective armor. Operations with up to 8MW of neutral beam power and 1.5MA plasma current are planned. Design and operational performance of the following systems are discussed: 1. Water-cooled graphite moveable limiter. 2. Water-cooled graphite fixed limiter and neutral beam wall armor. 3. Radiatively cooled Inconel divertor plates.
Results from scanning electron microscopy, Fourier transform infrared spectroscopy and the measurement of thermally stimulated current show that a high density of the physical defects and the chemical defects are introduced into the surface of the silicone rubber plates after they are treated by corona discharge plasma. These defects behave electrically as shallow electron traps, leading to the formation of a uniform discharge in air at higher pressure when the corona-modified silicone rubber is used in dielectric barrier discharge.
The MEX-15 is a conceptual design of a Multipurpose Reactor with thermal power of 15 MW and this reactor is pool type with fuel plates U{sub 3}0{sub 8}-Al of low enrichment uranium. This report presents the static calculation for the MEX-15 reactor using SRAC code system and was developed under the collaboration agreement between ININ-JAERI in Research Reactor Technology Development Division of Department of Research Reactor in Tokai Research Establishment. (Author)
A work on the world of astrophysics primarily for lay readers. The author writes only about the discoveries he ''experienced'' during the past 25 years (before 1979). Illustrated somewhat in color plus a set of superb colar plates. Contents, abridged: The long life of stars. The life story of the sun. The life story of massive stars. The end of stars. How stars are born. Planets and their inhabitants.
Soil placed over any sealant/barrier system can provide a protective mantle if the soil is not lost by erosion. Vegetation is an attractive choice for controlling erosion because it can provide an economic self-renewing cover that serves to reduce erosion by both wind and water. Vegetation alone, however, may not adequately stabilize the surface in extremely arid areas. In those areas, a properly designed surface treatment of rock cover, perhaps in conjunction with vegetation, may be necessary to stabilize the tailings surfaces. The objective of this program is to establish guidelines for surface stabilization that are compatible with sealant/barrier systems and that are suited to soils and climates at inactive uranium mill tailings sites. These guidelines will provide the means to estimate potential vegetation cover, potential erosion, effects of surface treatments on sealant/barrier systems, and costs of vegetation and rock covers. Methods for establishing ...
The methods of superconducting device fabrication by lithography and multilevel processing usually require a number of processing steps with lithographic resolution and alignment adequate for the scale of the device be fabricated. As an alternative, the focused ion beam (FIB) microscope is increasingly being used directly to fabricate devices. A major advantage of using a FIB compared to other lithography methods is its flexibility and high resolution. It allows in-situ, milling (#propor to#5 nm at a beam current of 1 pA) to a variety of depths, and imaging (2 nm) of the sample. In this paper we describe our development of junction fabrication techniques using the FIB and their application in creating a range of potential sensor devices and quantum electronics applications. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)
Focussed ion beam (FIB) processing has been applied to the fabrication of novel InP-based cleaved coupled cavity (CCC) quantum cascade lasers (QCL). Gas assisted etching using XeF{sub 2} has been shown to significantly reduce the redeposition of sputtered material onto the mirror surfaces during final milling. For the unprocessed laser a broad spread of lasing peaks are observed between 9.72{mu}m to 9.78{mu}m at a current of 380mA (1kA/cm{sup -2}). After FIB processing, substantial side mode suppression is observed on applying a current of 20mA (100A/cm{sup -2}) to the short section and the main lasing peak is observed at 9.77{mu}m.
Focussed ion beam (FIB) processing has been applied to the fabrication of novel InP-based cleaved coupled cavity (CCC) quantum cascade lasers (QCL). Gas assisted etching using XeF_2 has been shown to significantly reduce the redeposition of sputtered material onto the mirror surfaces during final milling. For the unprocessed laser a broad spread of lasing peaks are observed between 9.72#mu#m to 9.78#mu#m at a current of 380mA (1kA/cm"-"2). After FIB processing, substantial side mode suppression is observed on applying a current of 20mA (100A/cm"-"2) to the short section and the main lasing peak is observed at 9.77#mu#m.
As a result of nuclear power plant accidents, large areas receive radioactive inputs of Cs-137. This cesium accumulates in herbs growing in such territories. The problem is whether the herbs contaminated by radiocesium may be used as a raw material for medicine. The answer depends on the amount of Cs-137 transfered from the contaminated raw material to the medicine. We have presented new results of the transfer of Cs-137 from contaminated Digitalis grandiflora Mill. and Convallaria majalis L. to medicine. We found that the extraction of Cs-137 depends strongly on the hydrophilicity of the solvent. For example 96.5%(vol.) ethyl alcohol extracts less Cs-137 (11.6%) than 40%(vol.) ethyl alcohol or pure water (66.2%). The solubility of the cardiac glycosides is inverse to the solubility of cesium, which may be of use in the technological processes for manufacturing ecologically pure herbal medicine.
Ionizing radiation has been used to treat poultry to remove harmful microorganisms, mainly Salmonella, which contaminates chicken, goose and other fresh and frozen poultry. This microorganism is sensitive to low dose radiation. Thus, irradiating these foods with doses between 1 to 7 kGy results in a large reduction of bacteria. Since it is necessary to determine whether irradiation has occurred and to what extend, this work studied the signal produced by ionizing radiation within the hard crystalline matrix of chicken`s bone to establish a control method. Chicken`s drumsticks were irradiated and bones separated from flesh were lyophilized and milled. ESR spectrum was then obtained. The ESR signal increased linearly with dose over the range 0.25 to 8.0 kGy. Free radicals evaluated during 30 days after irradiation showed stable in this period. (Author).
Due to the well-establish corrosion problems of Alloy 600 as a steam-generator material and the subsequent focus on thermally treated (TT) Alloy 690 and Alloy 800 as alternative materials, a systematic analysis of the corrosion behavior of these two latter alloys is warranted. Corrosion test results for Alloys 690 TT and 800 were collected and organized in the form of corrosion mode diagrams. Selected data for mill annealed (MA) Alloy 600 were also included for reference. The corrosion mode diagrams correlate the modes of corrosion degradation observed in tests as functions of the environment pH and electrochemical potential (ECP). The diagrams confirm that Alloys 690TT shows some susceptibility in caustic environments, and Alloy 800 shows susceptibility in both caustic and highly acidic environments. (authors). 6 figs., 5 refs.
Due to the well-establish corrosion problems of Alloy 600 as a steam-generator material and the subsequent focus on thermally treated (TT) Alloy 690 and Alloy 800 as alternative materials, a systematic analysis of the corrosion behavior of these two latter alloys is warranted. Corrosion test results for Alloys 690 TT and 800 were collected and organized in the form of corrosion mode diagrams. Selected data for mill annealed (MA) Alloy 600 were also included for reference. The corrosion mode diagrams correlate the modes of corrosion degradation observed in tests as functions of the environment pH and electrochemical potential (ECP). The diagrams confirm that Alloys 690TT shows some susceptibility in caustic environments, and Alloy 800 shows susceptibility in both caustic and highly acidic environments. (authors). 6 figs., 5 refs.
The main sources of energy that might be available in remote low populated areas of Libya are either diesel generating units or wind mills for water pumping. Several problems in the working performance of these two types of energy production may arise due to environmental conditions. Direct conversion of solar energy can replace other ways of energy delivery or production, especially in this country where the solar radiation all year is relatively high. Direct conversion of solar energy is relatively expensive, however the cost of erecting long feeders and supervising them may be much more expensive than the usage of solar systems. This paper investigates the economics associated with either solutions of energy production. A case study is given in detail to supply one of the remote areas with a population of about 250. (author)
Composting of sawdust and paper mill sludge, using a 'Kneer' process reactor, was studied in an attempt to elaborate upon organic matter transformation during the process and to define parameters to measure the compost maturity level. Temperature, electron paramagnetic resonance data, ash and C, H, N and S contents, and a spectroscopic method using ultraviolet-visible (UV-VIS) for alkaline (pH = 8.5) and solid samples was used to study the maturity of the compost samples. These parameters were measured in 6 humic acids extracted from the compost samples during 29 days. The results of this work show that the 'Kneer' process is efficient in transforming ligno-celulitic residues in a short time (29 days), into an organic fertilizer material with application perspectives (author)
Studies of asphalt emulsion sealants conducted by the Pacific Northwest Laboratory have demonstrated that the sealants are effective in containing radon and other potentially hazardous material within uranium tailings. The laboratory and field studies have further demonstrated that radon exhalation from uranium tailings piles can be reduced by greater than 99% to near background levels. Field tests at the tailings pile in Grand Junction, Colorado, confirmed that an 8-cm admix seal containing 22 wt% asphalt could be effectively applied with a cold-mix paver. Other techniques were successfully tested, including a soil stabilizer and a hot, rubberized asphalt seal that was applied with a distributor truck. After the seals were applied and compacted, overburden was applied over the seal to protect the seal from ultraviolet degradation.
Studies of asphalt emulsion sealants have demonstrated that the sealants are effective in containing radon and other potentially hazardous material within uranium tailings. The laboratory and field studies have further demonstrated that radon exhalation from uranium tailings piles can be reduced by greater than 99% to less than background levels. Field tests at the tailings pile in Grand Junction, Colorado confirmed that an 8-cm admix seal containing 22 wt % asphalt could be effectively applied with a cold-mix paver. Other techniques were successfully tested, including a soil stabilizer and a hot, rubberized asphalt seal that was applied with a distributor truck. After the seals were applied and conpacted, overburden was applied over the seal to protect the seal from ultraviolet degradation. 14 figures.