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Sample records for sheet phoenix az

  1. EnviroAtlas - Phoenix, AZ - Block Groups

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Phoenix, AZ EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  2. EnviroAtlas - Phoenix, AZ - BenMAP Results by Block Group

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 2,434 block groups in Phoenix, AZ. The US EPA's...

  3. EnviroAtlas - Phoenix, AZ - Meter-Scale Urban Land Cover (MULC) Data (2010)

    U.S. Environmental Protection Agency — The EnviroAtlas Phoenix, AZ Meter-Scale Urban Land Cover (MULC) data and map were generated from USDA NAIP (National Agricultural Imagery Program) four band (red,...

  4. EnviroAtlas - Phoenix, AZ - Ecosystem Services by Block Group

    U.S. Environmental Protection Agency — This dataset presents environmental benefits of the urban forest in 2,434 block groups in Phoenix, Arizona. Carbon attributes, pollution removal and value, and...

  5. Geologie study off gravels of the Agua Fria River, Phoenix, AZ

    Langer, W.H.; Dewitt, E.; Adams, D.T.; O'Briens, T.

    2010-01-01

    The annual consumption of sand and gravel aggregate in 2006 in the Phoenix, AZ metropolitan area was about 76 Mt (84 million st) (USGS, 2009), or about 18 t (20 st) per capita. Quaternary alluvial deposits in the modern stream channel of the Agua Fria River west of Phoenix are mined and processed to provide some of this aggregate to the greater Phoenix area. The Agua Fria drainage basin (Fig. 1) is characterized by rugged mountains with high elevations and steep stream gradients in the north, and by broad alluvial filled basins separated by elongated faultblock mountain ranges in the south. The Agua Fria River, the basin’s main drainage, flows south from Prescott, AZ and west of Phoenix to the Gila River. The Waddel Dam impounds Lake Pleasant and greatly limits the flow of the Agua Fria River south of the lake. The southern portion of the watershed, south of Lake Pleasant, opens out into a broad valley where the river flows through urban and agricultural lands to its confluence with the Gila River, a tributary of the Colorado River.

  6. Influence of inorganic acid pickling on the corrosion resistance of magnesium alloy AZ31 sheet

    Nwaogu, Ugochukwu Chibuzoh; Blawert, C.; Scharnagl, N.

    2009-01-01

    Surface contaminants as a result of thermo-mechanical processing of magnesium alloys, e.g. sheet rolling, can have a negative effect on the corrosion resistance of magnesium alloys. Especially contaminants such as Fe, Ni and Cu, left on the surface of magnesium alloys result in the formation...... of micro-galvanic couples and can therefore increase corrosion attack on these alloys. Due to this influence they should be removed to obtain good corrosion resistance. In this study, the effect of inorganic acid pickling on the corrosion behaviour of a commercial AZ31 magnesium alloy sheet...... cleaning the AZ31 sheet. However, to obtain reasonable corrosion resistance at least 5 mu m of the surface of AZ31 magnesium alloy sheet have to be removed....

  7. Effects of organic acid pickling on the corrosion resistance of magnesium alloy AZ31 sheet

    Nwaogu, Ugochukwu Chibuzoh; Blawert, C.; Scharnagl, N.

    2010-01-01

    mu m of the contaminated surface was required to reach corrosion rates less than 1 mm/year in salt spray condition. Among the three organic acids examined, acetic acid is the best choice. Oxalic acid can be an alternative while citric acid is not suitable for cleaning AZ31 sheet, because......Organic acids were used to clean AZ31 magnesium alloy sheet and the effect of the cleaning processes on the surface condition and corrosion performance of the alloy was investigated. Organic acid cleanings reduced the surface impurities and enhanced the corrosion resistance. Removal of at least 4...

  8. Development of Rolling Schedules for AZ31 Magnesium Alloy Sheets

    2015-06-01

    Materials 2 2.2 Hot Rolling 3 2.2 Sample Characterization: Microstructure and Tensile Properties 3 3. Rolling Experiments 5 3.1 High-Temperature...material systems for protective and structural applications, especially in ground vehicles. Magnesium (Mg), due to its low density (~25% that of steel ...applications, wrought Mg is difficult to produce in thin sheets because of its inherently low ductility . As a result, Mg sheet is often produced at

  9. Stamping of Thin-Walled Structural Components with Magnesium Alloy AZ31 Sheets

    Chen, F.-K.; Chang, C.-K.

    2005-01-01

    In the present study, the stamping process for manufacturing cell phone cases with magnesium alloy AZ31 sheets was studied using both the experimental approach and the finite element analysis. In order to determine the proper forming temperature and set up a fracture criterion, tensile tests and forming limit tests were first conducted to obtain the mechanical behaviors of AZ31 sheets at various elevated temperatures. The mechanical properties of Z31 sheets obtained from the experiments were then adopted in the finite element analysis to investigate the effects of the process parameters on the formability of the stamping process of cell phone cases. The finite element simulation results revealed that both the fracture and wrinkle defects could not be eliminated at the same time by adjusting blank-holder force or blank size. A drawbead design was then performed using the finite element simulations to determine the size and the location of drawbead required to suppress the wrinkle defect. An optimum stamping process, including die geometry, forming temperature, and blank dimension, was then determined for manufacturing the cell phone cases. The finite element analysis was validated by the good agreement between the simulation results and the experimental data. It confirms that the cell phone cases can be produced with magnesium alloy AZ31 sheet by the stamping process at elevated temperatures

  10. Influence of urban form on landscape pattern and connectivity in metropolitan regions: a comparative case study of Phoenix, AZ, USA, and Izmir, Turkey.

    Park, Sohyun; Hepcan, Çiğdem C; Hepcan, Şerif; Cook, Edward A

    2014-10-01

    Although ecological connectivity conservation in urban areas has recently been recognized as an important issue, less is known about its relationship to urban form and landscape pattern. This study investigates how urban morphology influences regional ecosystem pattern and landscape connectivity. Two metropolitan landscapes, Phoenix, AZ, USA, and Izmir, Turkey, were compared, both of which are fast-growing regions in their national context. A wide range of variables were considered for identifying natural and urban properties. The natural characteristics include typology of urban ecosystems, urban to natural cover ratio, dominant habitat type, urban biodiversity, landscape context, and connectivity conservation efforts. Urban parameters examine urban form, urban extent, urban cover proportion, growth rate, populations, urban gradient, major drivers of urbanization, urban density, and mode/approach of urban development. Twelve landscape metrics were measured and compared across the natural patches. Results show that there is little difference in landscape connectivity in the rural zones of Phoenix and Izmir, although Phoenix has slightly higher connectivity values. The connectivity variance in urbanized areas, however, is significantly dependent on the region. For example, Phoenix urban zones have substantially lower connectivity than either urban or suburban zones in Izmir. Findings demonstrate that small and compact urban settlements with more dense populations are more likely to conserve landscape connectivity compared to multiple-concentric but amalgamated urban form spreading all over the landscape (aka urban sprawl).

  11. EnviroAtlas - Phoenix, AZ - 51m Riparian Buffer Forest Cover

    This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the riparian buffer is less forested. The displayed line represents the center of the analyzed riparian buffer. The water bodies analyzed include hydrologically connected streams, rivers, connectors, reservoirs, lakes/ponds, ice masses, washes, locks, and rapids within the Atlas Area. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

  12. EnviroAtlas - Phoenix, AZ - 51m Riparian Buffer Vegetated Cover

    This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the riparian buffer is less vegetated. The displayed line represents the center of the analyzed riparian buffer. The water bodies analyzed include hydrologically connected streams, rivers, connectors, reservoirs, lakes/ponds, ice masses, washes, locks, and rapids within the Atlas Area. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

  13. Double fillet lap of laser welding of thin sheet AZ31B Mg alloy

    Ishak, Mahadzir; Salleh, M. N. M.

    2018-05-01

    In this paper, we describe the experimental laser welding of thin sheet AZ31B using double fillet lap joint method. Laser welding is capable of producing high quality weld seams especially for small weld bead on thin sheet product. In this experiment, both edges for upper and lower sheets were subjected to the laser beam from the pulse wave (PW) mode of fiber laser. Welded sample were tested their joint strength by tensile-shear strength method and the fracture loads were studied. Strength for all welded samples were investigated and the effect of laser parameters on the joint strength and appearances were studied. Pulsed energy (EP) from laser process give higher effect on joint strength compared to the welding speed (WS) and angle of irradiation (AOI). Highest joint strength was possessed by sample with high EP with the same value of WS and AOI. The strength was low due to the crack defect at the centre of weld region.

  14. Pathogen and nutrient pulsing and attenuation in "accidental" urban wetland networks along the Salt River in Phoenix, AZ

    Palta, M. M.; Grimm, N. B.

    2013-12-01

    Increases in available nutrients and bacteria in urban streams are at the forefront of research concerns within the ecological and medical communities, and both pollutants are expected to become more problematic under projected changes in climate. Season, discharge, instream conditions (oxygen, water velocity), and weather conditions (antecedent moisture) all may influence loading rates to and the retention capabilities of wetlands fed by urban runoff and storm flow. The aim of this research was to examine the effect of these variables on nutrient (nitrogen, phosphorus) and Escherichia coli (E. coli) loading and attenuation along flow paths in urban wetland networks along the Salt River in Phoenix, AZ. Samples were collected for one year along flowpaths through wetlands that formed below six perennially flowing outfalls. Collection took place monthly during baseflow (dry season) conditions, and before and immediately following storm events, in the summer monsoon and winter rainy seasons. Water quality was assessed at the following points: immediately downstream of the outfall, mid-wetland, and downstream of the wetland. For determination of E. coli counts, samples were plated on coliform-selective media (Chromocult) and incubated for 24 hours. Plates were then used to enumerate E. coli. For determination of nutrient concentrations, samples were filtered and frozen until they could be analyzed by ion chromatography and automated wet chemistry. During both summer and winter, total discharge into the wetlands increased during storm events. Concentrations of PO43+, NH4+, and E. coli were significantly higher following storm events than during baseflow conditions, and post-storm peaks in concentration ('pulses') were higher during the summer monsoon than in winter storms. Pulses of pollutants during storms were highest when preceded by hot, dry conditions. NO3- was high in both base and stormflow. E. coli counts and nutrient concentrations dropped along flowpaths

  15. Plastic Deformation Characteristics Of AZ31 Magnesium Alloy Sheets At Elevated Temperature

    Park, Jingee; Lee, Jongshin; You, Bongsun; Choi, Seogou; Kim, Youngsuk

    2007-01-01

    Using lightweight materials is the emerging need in order to reduce the vehicle's energy consumption and pollutant emissions. Being a lightweight material, magnesium alloys are increasingly employed in the fabrication of automotive and electronic parts. Presently, magnesium alloys used in automotive and electronic parts are mainly processed by die casting. The die casting technology allows the manufacturing of parts with complex geometry. However, the mechanical properties of these parts often do not meet the requirements concerning the mechanical properties (e.g. endurance strength and ductility). A promising alternative can be forming process. The parts manufactured by forming could have fine-grained structure without porosity and improved mechanical properties such as endurance strength and ductility. Because magnesium alloy has low formability resulted form its small slip system at room temperature it is usually formed at elevated temperature. Due to a rapid increase of usage of magnesium sheets in automotive and electronic industry it is necessary to assure database for sheet metal formability and plastic yielding properties in order to optimize its usage. Especially, plastic yielding criterion is a critical property to predict plastic deformation of sheet metal parts in optimizing process using CAE simulation. Von-Mises yield criterion generally well predicts plastic deformation of steel sheets and Hill'1979 yield criterion predicts plastic deformation of aluminum sheets. In this study, using biaxial tensile test machine yield loci of AZ31 magnesium alloy sheet were obtained at elevated temperature. The yield loci ensured experimentally were compared with the theoretical predictions based on the Von-Mises, Hill, Logan-Hosford, and Barlat model

  16. Warm Deep Drawing of Rectangular Parts of AZ31 Magnesium Alloy Sheet Adopting Variable Blank Holder Force

    Peng Yinghong; Chang Qunfeng; Li Dayong; Zeng Xiaoqin

    2007-01-01

    AZ31 magnesium alloy sheet with good shape and formability is fabricated by warm cross rolling. Uniaxial tensile tests are conducted using a Gleeble 3500 thermal - mechanical simulator, and the mechanical properties of AZ31 magnesium alloy sheet are analyzed. A warm deep drawing process of square part is also simulated by the finite element method. The influences of blank holder force on the formability are numerically investigated. A double-action hydraulic press that can realize adjustable blank holder forces is developed and its working principle and control system are introduced. Some warm deep drawing experiments of square parts of AZ31 magnesium alloy sheet are also performed. Different variation schemes of the blank holder force with the stroke of the punch are tested, and the experiment results are compared. Results show that the suitable blank holder force variation scheme is a ladder curve with the punch stroke. Adopting the variable blank holder force technique can improve 13.2% of the drawing depth of square parts of AZ31 magnesium alloy sheet

  17. Chitosan coatings crosslinked with genipin for corrosion protection of AZ31 magnesium alloy sheets.

    de Y Pozzo, Ludmila; da Conceição, Thiago F; Spinelli, Almir; Scharnagl, Nico; Pires, Alfredo T N

    2018-02-01

    In this study, coatings of chitosan crosslinked with genipin were prepared on sheets of AZ31 magnesium alloy and their corrosion protection properties were characterized by means of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The coatings were also characterized by means of FTIR and XPS. It was observed that the crosslinking process decreases the corrosion current and shifts the corrosion potential of the alloy to less negative values. The EIS analysis demonstrated that the crosslinking process increases the maximum impedance after short and long exposure times. The superior performance of the crosslinked coatings is related to a lower degree of swelling, as observed in the swelling tests carried out on free-standing films. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Superfund Record of Decision (EPA Region 9): Nineteenth Avenue Landfill, Phoenix, AZ. (First remedial action), September 1989. Final report

    1989-01-01

    The 213-acre Nineteenth Avenue Landfill is in an industrial area of Maricopa County, Phoenix, Arizona. State permitted landfill operations were conducted from 1957 to 1979 during which time approximately nine million cubic yards of municipal refuse, solid and liquid industrial wastes, and some medical wastes and materials containing low levels of radioactivity were deposited in the landfill. The State ordered the landfill closed in 1979 due to the periodic inundation of the landfill by flood waters from the Salt River Channel. Subsequently, the city covered the site with fill, stockpiled soil for final capping, installed ground water monitoring wells, built berms around the landfill, and installed a methane gas collection system. The remedial action is designed to mitigate threats resulting from flooding of the landfill, which has occurred intermittently since 1965. The primary contaminants of concern in the soil/refuse include VOCs such as toluene and xylenes

  19. Influence of pulsed current on deformation mechanism of AZ31B sheets during tension

    Liu, Kai [National Die & Mold CAD Engineering Research Center, Shanghai Jiao Tong University, 1954 Hua Shan Road, Shanghai 200030 (China); Dong, Xianghuai, E-mail: dongxh@sjtu.edu.cn [National Die & Mold CAD Engineering Research Center, Shanghai Jiao Tong University, 1954 Hua Shan Road, Shanghai 200030 (China); Xie, Huanyang [Shanghai Superior Die Technology Co., Ltd, 775 Jinsui Road, Shanghai 201209 (China); Wu, Yunjian; Peng, Fang [National Die & Mold CAD Engineering Research Center, Shanghai Jiao Tong University, 1954 Hua Shan Road, Shanghai 200030 (China)

    2016-08-15

    The tensile tests of AZ31B sheets were carried out under pulsed current (PC) of different frequencies, and then the deformation mechanism at different conditions was analyzed by X-Ray Diffraction. The results show that PC does not change the initial yield stress, but reduces the work hardening rate and induces softening effect. Furthermore, electroplasticity effect is controlled by thermal activation. When Z (Zener-Hollomon parameter) is high, the effect of PC is limited, causing a relatively weak electroplasticity effect. With the increasing of Z, the effect of PC strengthens. When Z reaches the critical condition, the activated slip systems obviously change because of PC, which induces the change of texture evolution and the discontinuous change of the intensity of electroplasticity. When Z is low, electroplasticity effect reaches a saturate condition and does not change with Z. Moreover, higher frequency contributes to the dislocation annihilation at all the slip systems, and then increasing frequency can strengthen the extra softening effect of PC. - Highlights: • Pulsed current does not change the initial yield stress, but reduce the work hardening rate and cause softening effect. • Increasing frequency can strengthen the softening effect. • The rules of the softening effect at different deformation condition are different. • The influence of current on deformation mechanism was analyzed by XRD.

  20. Enhancement of tensile ductility and stretch formability of AZ31 magnesium alloy sheet processed by cross-wavy bending

    Huo, Qinghuan; Yang, Xuyue; Sun, Huan; Li, Bin; Qin, Jia; Wang, Jun; Ma, Jijun

    2013-01-01

    Highlights: •The AZ31 Mg alloy sheet is deformed to 4 passes at 673 K by cross-wavy bending. •A fine-grained microstructure and a weak and random texture are achieved. •Different softening mechanisms significantly affect the microstructure evolution. •The tensile ductility and stretch formability enhance dramatically. -- Abstract: The microstructure and texture evolution in the sheets of AZ31 magnesium alloy was studied by means of cross-wavy bending for 4 passes at 673 K. The bended samples were examined by optical microscopy and electron backscatter diffraction analysis. Finite element analysis suggested an inhomogeneous deformation at each pass. Following cross-wavy bending, a fine-grained microstructure with an average grain size of ∼8 μm and a weak and random basal texture were achieved. Accumulative effective strain was almost equal in the whole sheet at the end. Different work softening mechanisms significantly affected the evolution of the microstructure. Dynamic recovery played an important role during the first three bending passes whereas, in contrast, dynamic recrystallization dominated the evident grain refinement during the last pass. The tensile ductility and stretch formability of the 4-pass sheet at room temperature were distinctly enhanced compared to the initial sheet (1.55 and 2 times larger, respectively). These prominent increases were mainly attributed to texture randomizing rather than texture weakening alone

  1. Application of YAG Laser TIG Arc Hybrid Welding to Thin AZ31B Magnesium Alloy Sheet

    Kim, Taewon; Kim, Jongcheol; Hasegawa, Yu; Suga, Yasuo

    A magnesium alloy is said to be an ecological material with high ability of recycling and lightweight property. Especially, magnesium alloys are in great demand on account of outstanding material property as a structural material. Under these circumstances, research and development of welding process to join magnesium alloy plates are of great significance for wide industrial application of magnesium. In order to use it as a structure material, the welding technology is very important. TIG arc welding process is the most ordinary process to weld magnesium alloy plates. However, since the heat source by the arc welding process affects the magnesium alloy plates, HAZ of welded joint becomes wide and large distortion often occurs. On the other hand, a laser welding process that has small diameter of heat source seems to be one of the possible means to weld magnesium alloy in view of the qualitative improvement. However, the low boiling point of magnesium generates some weld defects, including porosity and solidification cracking. Furthermore, precise edge preparation is very important in butt-welding by the laser welding process, due to the small laser beam diameter. Laser/arc hybrid welding process that combines the laser beam and the arc is an effective welding process in which these two heat sources influence and assist each other. Using the hybrid welding, a synegistic effect is achievable and the disadvantages of the respective processes can be compensated. In this study, YAG laser/TIG arc hybrid welding of thin magnesium alloy (AZ31B) sheets was investigated. First of all, the effect of the irradiation point and the focal position of laser beam on the quality of a weld were discussed in hybrid welding. Then, it was confirmed that a sound weld bead with sufficient penetration is obtained using appropriate welding conditions. Furthermore, it was made clear that the heat absorption efficiency is improved with the hybrid welding process. Finally, the tensile tests

  2. Room Temperature Shear Band Development in Highly Twinned Wrought Magnesium AZ31B Sheet

    Scott, Jon; Miles, Michael; Fullwood, David; Adams, Brent; Khosravani, Ali; Mishra, Raja K.

    2013-01-01

    Failure mechanisms were studied in wrought AZ31B magnesium alloy after forming under different strain paths. Optical micrographs were used to observe the shear band formation and regions of high twin density in samples strained under uniaxial, biaxial, and plane strain conditions. Interrupted testing at 4 pct effective strain increments, until failure, was used to observe the evolution of the microstructure. The results showed that shear bands, with a high percentage of twinned grains, appeared early in the samples strained under biaxial or plane strain tension. These bands are similar to those seen in uniaxial tension specimens just prior to failure where the uniaxial tensile ductility was much greater than that observed for plane strain or biaxial tension conditions. A forming limit diagram for AZ31B, which was developed from the strain data, showed that plane strain and biaxial tension had very similar limit strains; this contrasts with materials like steel or aluminum alloys, which typically have greater ductility in biaxial tension compared to plane strain tension.

  3. Phoenix Production

    US Agency for International Development — Phoenix is a commercial off-the-shelf, web-based financial management system configured for USAID. Phoenix provides information about commitments, obligations, and...

  4. Mechanical Behavior of AZ31B Mg Alloy Sheets under Monotonic and Cyclic Loadings at Room and Moderately Elevated Temperatures

    Ngoc-Trung Nguyen

    2014-02-01

    Full Text Available Large-strain monotonic and cyclic loading tests of AZ31B magnesium alloy sheets were performed with a newly developed testing system, at different temperatures, ranging from room temperature to 250 °C. Behaviors showing significant twinning during initial in-plane compression and untwinning in subsequent tension at and slightly above room temperature were recorded. Strong yielding asymmetry and nonlinear hardening behavior were also revealed. Considerable Bauschinger effects, transient behavior, and variable permanent softening responses were observed near room temperature, but these were reduced and almost disappeared as the temperature increased. Different stress–strain responses were inherent to the activation of twinning at lower temperatures and non-basal slip systems at elevated temperatures. A critical temperature was identified to account for the transition between the twinning-dominant and slip-dominant deformation mechanisms. Accordingly, below the transition point, stress–strain curves of cyclic loading tests exhibited concave-up shapes for compression or compression following tension, and an unusual S-shape for tension following compression. This unusual shape disappeared when the temperature was above the transition point. Shrinkage of the elastic range and variation in Young’s modulus due to plastic strain deformation during stress reversals were also observed. The texture-induced anisotropy of both the elastic and plastic behaviors was characterized experimentally.

  5. Phoenix Study

    U.S. Environmental Protection Agency — Phoenix Traffic and Mobile Data. This dataset is associated with the following publication: Baldauf , R., V. Isakov , P. Deshmukh, and A. Venkatram. Influence of...

  6. Experimental Characterization and Material Modelling of an AZ31 Magnesium Sheet Alloy at Elevated Temperatures under Consideration of the Tension-Compression Asymmetry

    Behrens, B.-A.; Bouguecha, A.; Bonk, C.; Dykiert, M.

    2017-09-01

    Magnesium sheet alloys have a great potential as a construction material in the aerospace and automotive industry. However, the current state of research regarding temperature dependent material parameters for the description of the plastic behaviour of magnesium sheet alloys is scarce in literature and accurate statements concerning yield criteria and appropriate characterization tests to describe the plastic behaviour of a magnesium sheet alloy at elevated temperatures in deep drawing processes are to define. Hence, in this paper the plastic behaviour of the well-established magnesium sheet alloy AZ31 has been characterized by means of convenient mechanical tests (e. g. tension, compression and biaxial tests) at temperatures between 180 and 230 °C. In this manner, anisotropic and hardening behaviour as well as differences between the tension-compression asymmetry of the yield locus have been estimated. Furthermore, using the evaluated data from the above mentioned tests, two different yield criteria have been parametrized; the commonly used Hill’48 and an orthotropic yield criterion, CPB2006, which was developed especially for materials with hexagonal close packed lattice structure and is able to describe an asymmetrical yielding behaviour regarding tensile and compressive stress states. Numerical simulations have been finally carried out with both yield functions in order to assess the accuracy of the material models.

  7. Hydro mechanical deep-drawing and high pressure sheet metal forming as forming technologies for the production of complex parts made of magnesium sheet metal AZ31B-0; Hydromechanisches Tiefziehen und Hochdruckblechumformung als Verfahren zur Herstellung komplexer Bauteile aus Magnesiumfeinblechen des Typs AZ31B-0

    Viehweger, B.; Richter, G.; Duering, M.; Karabet, A. [Lehrstuhlleiter, BTU Cottbus, Lehrstuhl Konstruktion und Fertigung, Konrad-Wachsmann Allee 1, 03046 Cottbus (Germany); Sviridov, A.; Hartmann, H.; Richter, U. [Forschungs- und Qualitaetszentrum Oderbruecke gGmbH Eisenhuettenstadt (Germany)

    2004-07-01

    Semi - finished sheet - metal products made of magnesium alloys such as AZ31B are known as better deformable at temperatures in the range of 175 C - 240 C. By means of hydroforming technologies, as there are hydro mechanical deep-drawing and high pressure sheet metal forming, the influence of different forming parameters on the forming results has been investigated. A more complex experimental geometry was deformed applying forming temperatures of 175 C, 200 C, 225 C and 240 C and accordingly adjusted forces of the blank holder. Concerning the applied forming - methods and experimental parameters the forming results have been evaluated and compared regarding the decrease of sheet thickness and the development of small radii. For some experimental parts, which have been deformed by means of high pressure sheet metal forming at temperatures of 175 C and 225 C, supplementary investigations have been carried out in order to determine the evolution of characteristic surface values in dependence on the forming operation. On the basis of these results practical recommendations for the limits of application of aforementioned forming technologies for AZ31B-0 magnesium sheet metal are given. (Abstract Copyright [2004], Wiley Periodicals, Inc.) [German] Eine gute Umformbarkeit von Blechhalbzeugen aus Magnesiumknetlegierungen stellt sich bekanntlich bei Anwendung von Umformtemperaturen im Bereich von 175 C - 240 C ein. Anhand der wirkmedienbasierten Umformverfahren hydromechanisches Tiefziehen und Hochdruckblechumformung ist an handelsueblichen AZ31B-0 Feinblechen die Einstellung unterschiedlicher Umformparameter erprobt worden. Unter Verwendung von Umformtemperaturen von 175 C, 200 C, 225 C und 240 C und entsprechend angepassten Niederhalterdruecken ist eine praxisnahe Versuchsgeometrie ''Minihood'' ausgeformt worden. Im Hinblick auf angewendete Umformverfahren und Versuchsparameter wurde an den Versuchsbauteilen die Blechdickenabnahme und die

  8. In-process tool rotational speed variation with constant heat input in friction stir welding of AZ31 sheets with variable thickness

    Buffa, Gianluca; Campanella, Davide; Forcellese, Archimede; Fratini, Livan; Simoncini, Michela

    2017-10-01

    In the present work, friction stir welding experiments on AZ31 magnesium alloy sheets, characterized by a variable thickness along the welding line, were carried out. The approach adapted during welding consisted in maintaining constant the heat input to the joint. To this purpose, the rotational speed of the pin tool was increased with decreasing thickness and decreased with increasing thickness in order to obtain the same temperatures during welding. The amount by which the rotational speed was changed as a function of the sheet thickness was defined on the basis of the results given by FEM simulations of the FSW process. Finally, the effect of the in-process variation of the tool rotational speed on the mechanical and microstructural properties of FSWed joints was analysed by comparing both the nominal stress vs. nominal strain curves and microstructure of FSWed joints obtained in different process conditions. It was observed that FSW performed by keeping constant the heat input to the joint leads to almost coincident results both in terms of the curve shape, ultimate tensile strength and ultimate elongation values, and microstructure.

  9. Properties of Rolled AZ31 Magnesium Alloy Sheet Fabricated by Continuous Variable Cross-Section Direct Extrusion

    Liu, Yang; Li, Feng; Li, Xue Wen; Shi, Wen Yong

    2018-03-01

    Rolling is currently a widely used method for manufacturing and processing high-performance magnesium alloy sheets and has received widespread attention in recent years. Here, we combined continuous variable cross-section direct extrusion (CVCDE) and rolling processes. The microstructure and mechanical properties of the resulting sheets rolled at different temperatures from CVCDE extrudate were investigated by optical microscopy, scanning electron microscope, transmission electron microscopy and electron backscatter diffraction. The results showed that a fine-grained microstructure was present with an average grain size of 3.62 μm in sheets rolled from CVCDE extrudate at 623 K. Dynamic recrystallization and a large strain were induced by the multi-pass rolling, which resulted in grain refinement. In the 573-673 K range, the yield strength, tensile strength and elongation initially increased and then declined as the CVCDE temperature increased. The above results provide an important scientific basis of processing, manufacturing and the active control on microstructure and property for high-performance magnesium alloy sheet.

  10. Phoenix Trenches

    2008-01-01

    [figure removed for brevity, see original site] Annotated Version [figure removed for brevity, see original site] Left-eye view of a stereo pair [figure removed for brevity, see original site] Right-eye view of a stereo pair This image is a stereo, panoramic view of various trenches dug by NASA's Phoenix Mars Lander. The images that make up this panorama were taken by Phoenix's Surface Stereo Imager at about 4 p.m., local solar time at the landing site, on the 131st, Martian day, or sol, of the mission (Oct. 7, 2008). In figure 1, the trenches are labeled in orange and other features are labeled in blue. Figures 2 and 3 are the left- and right-eye members of a stereo pair. For scale, the 'Pet Donkey' trench just to the right of center is approximately 38 centimeters (15 inches) long and 31 to 34 centimeters (12 to 13 inches) wide. In addition, the rock in front of it, 'Headless,' is about 11.5 by 8.5 centimeters (4.5 by 3.3 inches), and about 5 centimeters (2 inches) tall. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  11. 76 FR 62144 - Environmental Impact Statement for Implementation of Passenger Rail Service Between Tucson, AZ...

    2011-10-06

    ... impacts to the natural and built environment of those alternatives, and invite public participation in the... will provide programmatic assessment of environmental effects associated with the construction... Environmental Impact Statement for Implementation of Passenger Rail Service Between Tucson, AZ and Phoenix, AZ...

  12. Texture evolution in Nd:YAG-laser welds of AZ31 magnesium alloy hot rolled sheets and its influence on mechanical properties

    Commin, Lorelei; Dumont, Myriam; Rotinat, Rene; Pierron, Fabrice; Masse, Jean-Eric; Barrallier, Laurent

    2011-01-01

    Research highlights: → AZ31 LBW fusion zone results in Mg 17 (Al-Zn) 12 precipitation, twins formation and {0 0 2} texture modification. → The mechanical properties were reduced after LBW but the fracture occurred in the base metal. → The mechanical properties were reduced after LBW but the fracture occurred in the base metal. → A recovery of elongation and UTS can be achieved by a 300 deg. C/1 h heat treatment. The texture evolution is mainly responsible for the yield strength reduction in the fusion zone. - Abstract: AZ31 hot rolled magnesium alloy presents a strong basal texture. Using laser beam welding (LBW) as a joining process induces high temperature gradients leading to major texture changes. Electron back scattered diffraction (EBSD) was used to study the texture evolution, and tensile tests coupled with speckle interferometry were performed to understand its influence on mechanical properties. The random texture obtained in the LBW fusion zone is mainly responsible for the yield strength reduction.

  13. GMAP Phoenix 2013 data

    U.S. Environmental Protection Agency — mobile monitoring data from the 2013 Phoenix study. This dataset is associated with the following publication: Venkatram, A., V. Isakov , P. Deshmukh, and R....

  14. City of Phoenix - Energize Phoenix Program

    Laloudakis, Dimitrios J.

    2014-09-29

    Energize Phoenix (EPHX) was designed as an ambitious, large-scale, three-year pilot program to provide energy efficiency upgrades in buildings, along Phoenix’s new Light Rail Corridor – part of a federal effort to reduce energy consumption and stimulate job growth, while simultaneously reducing the country’s carbon footprint and promoting a shift towards a green economy. The program was created through a 2010 competitive grant awarded to the City of Phoenix who managed the program in partnership with Arizona State University (ASU), the state’s largest university, and Arizona Public Service (APS), the state’s largest electricity provider. The U.S. Department of Energy (DOE) Better Buildings Neighborhood Program (BBNP) and the American Recovery and Reinvestment Act (ARRA) of 2009 provided $25M in funding for the EPHX program. The Light Rail Corridor runs through the heart of downtown Phoenix, making most high-rise and smaller commercial buildings eligible to participate in the EPHX program, along with a diverse mix of single and multi-family residential buildings. To ensure maximum impact and deeper market penetration, Energize Phoenix was subdivided into three unique parts: i. commercial rebate program, ii. commercial financing program, and iii. residential program Each component was managed by the City of Phoenix in partnership with APS. Phoenix was fortunate to partner with APS, which already operated robust commercial and residential rebate programs within its service territory. Phoenix tapped into the existing utility contractor network, provided specific training to over 100 contracting firms, and leveraged the APS rebate program structure (energy efficiency funding) to launch the EPHX commercial and residential rebate programs. The commercial finance program was coordinated and managed through a contract with National Bank of Arizona, NBAZ, which also provided project capital leveraging EPHX finance funds. Working in unison, approved contractors

  15. CARDIOVASCULAR MORTALITY IN PHOENIX: PM1 IS A BETTER INDICATOR THAN PM2.5.

    EPA has obtained a 3-year database of particulate matter (PM) in Phoenix, AZ from 1995 - 1997 that includes elemental analysis by XRF of daily PM2.5. During this time period PM1 and PM2.5 TEOMs were run simultaneously for about 7 months during two periods of the year. Regressio...

  16. EnviroAtlas - Phoenix, AZ - Near Road Tree Buffer

    U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

  17. EnviroAtlas - Phoenix, AZ - Greenspace Proximity Gradient

    U.S. Environmental Protection Agency — In any given 1-square meter point in this EnviroAtlas dataset, the value shown gives the percentage of square meters of greenspace within 1/4 square kilometer...

  18. EnviroAtlas - Phoenix, AZ - Land Cover by Block Group

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, agriculture, and green space. Forest is combination...

  19. EnviroAtlas - Phoenix, AZ - Near Road Block Group Summary

    U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

  20. Phoenix's Workplace Map

    2008-01-01

    This image from NASA's Phoenix Mars Lander shows the spacecraft's recent activity site as of the 23rd Martian day of the mission, or Sol 22 (June 16, 2008), after the spacecraft touched down on the Red Planet's northern polar plains. The mosaic was taken by the lander's Surface Stereo Imager (SSI). Phoenix's solar panels are seen in the foreground. The trench informally called 'Snow White' was dug by Phoenix's Robotic Arm in a patch of Martian soil near the center of a polygonal surface feature, nicknamed 'Cheshire Cat.' The 'dump pile' is located at the top of the trench, and has been dubbed 'Croquet Ground.' The digging site has been nicknamed 'Wonderland.' Snow White, seen here in an SSI image from Sol 22 (June 16, 2008) is about 2 centimeters (.8 inches) deep and 30 centimeters (12 inches) long. As of Sol 24 (June 18, 2008), the trench is 5 centimeters (2 inches deep) and the trench has been renamed 'Snow White 1,' as a second trench has been dug to its right and nicknamed 'Snow White 2.' The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  1. Phoenix's Wet Chemistry Laboratory Units

    2008-01-01

    This image shows four Wet Chemistry Laboratory units, part of the Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) instrument on board NASA's Phoenix Mars Lander. This image was taken before Phoenix's launch on August 4, 2007. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  2. The PHOENIX Concept

    Van Tuyle, G.J.; Takahashi, H.; Todosow, M.; Aronson, A.L.; Slovik, G.C.; Horak, W.C.

    1991-01-01

    A proposed means of transmuting key long-lived radioactive isotopes, primarily the so-called minor actinides (Np, Am, Cm), using a hybrid proton-accelerator-sub-critical lattice, is described. It is argued that by partitioning the components of the light water reactor (LWR) spent fuel and by transmuting key elements, such as the plutonium, the minor actinides, and a few of the long-lived fission products, that some of the most significant challenges in building a waste repository can be substantially reduced. If spent fuel partitioning and transmutation were fully implemented, the time required to reduce the waste stream toxicity below that of uranium ore would be reduced from more than 10,000 years to approximately 30 years. The proposed machine, based on the described PHOENIX Concept, would transmute the minor actinides and much of the iodine produced by 75 LWRs, and would generate usable electricity (beyond that required to run the large accelerator) of 850 MW e . 14 refs., 29 figs

  3. Joining of AZ31 and AZ91 Mg alloys by friction stir welding

    B. Ratna Sunil

    2015-12-01

    Full Text Available Two dissimilar magnesium (Mg alloy sheets, one with low aluminium (AZ31 and another with high aluminium (AZ91 content, were successfully joined by friction stir welding (FSW. The effect of process parameters on the formation of hot cracks was investigated. A sound metallurgical joint was obtained at optimized process parameters (1400 rpm with 25 mm/min feed which contained fine grains and distributed β (Mg17Al12 phase within the nugget zone. An increasing trend in the hardness measurements has also confirmed more amount of dissolution of aluminium within the nugget zone. A sharp interface between nugget zone and thermo mechanical affected zone (TMAZ was clearly noticed at the AZ31 Mg alloy side (advancing but not on the AZ91 Mg alloy side (retreating. From the results it can be concluded that FSW can be effectively used to join dissimilar metals, particularly difficult to process metals such as Mg alloys, and hot cracking can be completely eliminated by choosing appropriate process parameters to achieve sound joint.

  4. Phoenix's Lay of the Land

    2008-01-01

    This image from NASA's Phoenix Mars Lander shows the spacecraft's recent activity site as of the 23rd Martian day of the mission, or Sol 22 (June 16, 2008), after the spacecraft touched down on the Red Planet's northern polar plains. The mosaic was taken by the lander's Surface Stereo Imager (SSI). Parts of Phoenix can be seen in the foreground. The first two trenches dug by the lander's Robotic Arm, called 'Dodo' and 'Goldilocks,' were enlarged on the 19th Martian day of the mission, or Sol 18 (June 12, 2008), to form one trench, dubbed 'Dodo-Goldilocks.' Scoops of material taken from those trenches are informally called 'Baby Bear' and 'Mama Bear.' Baby Bear was carried to Phoenix's Thermal and Evolved-Gas Analyzer, or TEGA, instrument for analysis, while Mama Bear was delivered to Phoenix's Microscopy, Electrochemistry and Conductivity Analyzer instrument suite, or MECA, for a closer look. The color inset picture of the Dodo-Goldilocks trench, also taken with Phoenix's SSI, reveals white material thought to be ice. More recently, on Sol 22 (June 16, 2008), Phoenix's Robotic Arm began digging a trench, dubbed 'Snow White,' in a patch of Martian soil near the center of a polygonal surface feature, nicknamed 'Cheshire Cat.' The 'dump pile' is located at the top of the trench, and has been dubbed 'Croquet Ground.' The digging site has been nicknamed 'Wonderland.' The Snow White trench, seen here in an SSI image from Sol 22 (June 16, 2008) is about 2 centimeters (.8 inches) deep and 30 centimeters (12 inches) long. As of Sol 25 (June 19, 2008), the trench is 5 centimeters (2 inches deep) and the trench has been renamed 'Snow White 1,' as a second trench has been dug to its right and nicknamed 'Snow White 2.' The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  5. Phoenix I energy extraction experiment

    Hoffman, J.M.; Patterson, E.L.; Tisone, G.C.; Moreno, J.B.

    1980-07-01

    Energy extraction experiments are reported for the Phoenix I amplifier driven by a discharge-initiated oscillator-preamplifier system operating on mixtures of either SF 6 -HI or SF 6 -C 2 H 6 and an electron-beam-initiated intermediate amplifer (lambda-3) fueled with H 2 and F 2 mixtures. When the oscillator-preamplifier system operated with mixtures of SF 6 -HI the input spectrum to the Phoenix I amplifier contained approx. 28 P-branch vibrational-rotational lines which were almost identical to the input spectrum from the H 2 -F 2 fueled oscillator. In this case the energy extraction measurements were essentially the same as the results obtained with the spectrum produced using H 2 and F 2 mixtures. For an input intensity of 10 7 W/cm 2 , 170 J were extracted from the amplifier. With the SF 6 -C 2 H 6 spectrum, extraction was only obtained from the first three excited vibrational levels. This result indicates that most of the energy in the amplifier could be extracted on the first three excited vibrational levels. It is shown that the extraction results can be fit with a simple two level model. The radius of curvature of the beam was estimated using a lateral shearing interferometer. It was found that the Phoenix I amplifier altered the radius of curvature

  6. Martian Surface as Seen by Phoenix

    2008-01-01

    This anaglyph, acquired by NASA's Phoenix Lander's Surface Stereo Imager on Sol 36, the 36th Martian day of the mission (July 1, 2008), shows a stereoscopic 3D view of a trench informally called 'Snow White' dug by Phoenix's Robotic Arm. Phoenix's solar panel is seen in the bottom right corner of the image. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  7. Alternative Fuels Data Center: Phoenix Cleans Up with Natural Gas

    Phoenix Cleans Up with Natural Gas to someone by E-mail Share Alternative Fuels Data Center : Phoenix Cleans Up with Natural Gas on Facebook Tweet about Alternative Fuels Data Center: Phoenix Cleans Up with Natural Gas on Twitter Bookmark Alternative Fuels Data Center: Phoenix Cleans Up with Natural

  8. Conformal, planarizing and bridging AZ5214-E layers deposited by a 'draping' technique on non-planar III V substrates

    Eliás, P.; Strichovanec, P.; Kostic, I.; Novák, J.

    2006-12-01

    A draping technique was tested for the deposition of positive-tone AZ5214-E photo-resist layers on non-planar (1 0 0)-oriented III-V substrates, which had a variety of three-dimensional (3D) topographies micromachined in them that consisted, e.g., of mesa ridges confined to side facets with variable tilt, inverted pyramidal holes and stubs confined to perpendicular side facets. All objects were sharp-edged. In each draping experiment, an AZ5214-E sheet was (1) formed floating on the water surface, (2) lowered onto a non-planar substrate and (3) draped over it during drying to form either self-sustained, or conformal, or planarizing layers over the non-planar substrates. The draping process is based on the depression of the glass transition temperature Tg of AZ5214-E material induced by penetrant water molecules that interact with AZ5214-E. During the process, the molecules are initially trapped under an AZ5214-E sheet and then transported out through the sheet via permeation. The water-AZ5214-E interaction modifies the stiffness κ of the sheet. The magnitude of the effect depends on temperature T and on partial water vapour pressure difference p(T, P, κ): the net effect is that Tg = f(C(T, P), p(T, P, κ)) is lowered as the concentration C of water increases with T and p, where P is the permeability of the sheet. The interaction depressed the Tg of the sheets as low as or lower than 53 °C for 6 µm thick sheets. At room temperature T Tg, the sheet becomes rubbery and mouldable by adhesion and capillary forces. As a result, it can either contour or planarize the topography depending on its geometry and thickness of the sheet.

  9. Phoenix v. 1.0-SNAPSHOT

    2016-09-21

    Phoenix is a Java Virtual Machine (JVM) based library for performing mathematical and astrodynamics calculations. It consists of two primary sub-modules, phoenix-math and phoenix-astrodynamics. The mathematics package has a variety of mathematical classes for performing 3D transformations, geometric reasoning, and numerical analysis. The astrodynamics package has various classes and methods for computing locations, attitudes, accesses, and other values useful for general satellite modeling and simulation. Methods for computing celestial locations, such as the location of the Sun and Moon, are also included. Phoenix is meant to be used as a library within the context of a larger application. For example, it could be used for a web service, desktop client, or to compute simple values in a scripting environment.

  10. 'Rosy Red' Soil in Phoenix's Scoop

    2008-01-01

    This image shows fine-grained material inside the Robotic Arm scoop as seen by the Robotic Arm Camera (RAC) aboard NASA's Phoenix Mars Lander on June 25, 2008, the 30th Martian day, or sol, of the mission. The image shows fine, fluffy, red soil particles collected in a sample called 'Rosy Red.' The sample was dug from the trench named 'Snow White' in the area called 'Wonderland.' Some of the Rosy Red sample was delivered to Phoenix's Optical Microscope and Wet Chemistry Laboratory for analysis. The RAC provides its own illumination, so the color seen in RAC images is color as seen on Earth, not color as it would appear on Mars. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  11. EnviroAtlas - Phoenix, AZ - Historic Places by Census Block Group

    U.S. Environmental Protection Agency — This EnviroAtlas dataset portrays the total number of historic places located within each Census Block Group (CBG). The historic places data were compiled from the...

  12. EnviroAtlas - Phoenix, AZ - Estimated Percent Green Space Along Walkable Roads

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates green space along walkable roads. Green space within 25 meters of the road centerline is included and the percentage is based on...

  13. EnviroAtlas - Phoenix, AZ - Estimated Percent Tree Cover Along Walkable Roads

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  14. EnviroAtlas - Phoenix, AZ - Residents with Potential Window Views of Water by Block Group

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  15. EnviroAtlas - Phoenix, AZ - 15m Riparian Buffer Forest Cover

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  16. EnviroAtlas - Phoenix, AZ - 51m Riparian Buffer Vegetated Cover

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  17. EnviroAtlas - Phoenix, AZ - Estimated Intersection Density of Walkable Roads

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...

  18. EnviroAtlas - Phoenix, AZ - Greenspace Around Schools by Block Group

    U.S. Environmental Protection Agency — This EnviroAtlas data set shows the number of schools in each block group in the EnviroAtlas community boundary as well as the number of schools where less than 25%...

  19. Winds at the Phoenix landing site

    Holstein-Rathlou, C.; Gunnlaugsson, H.P.; Merrison, J.P.

    2010-01-01

    Wind speeds and directions were measured on the Phoenix Lander by a mechanical anemometer, the so-called Telltale wind indicator. Analysis of images of the instrument taken with the onboard imager allowed for evaluation of wind speeds and directions. Daily characteristics of the wind data are hig...

  20. Discovery Learning: Zombie, Phoenix, or Elephant?

    Bakker, Arthur

    2018-01-01

    Discovery learning continues to be a topic of heated debate. It has been called a zombie, and this special issue raises the question whether it may be a phoenix arising from the ashes to which the topic was burnt. However, in this commentary I propose it is more like an elephant--a huge topic approached by many people who address different…

  1. Digibaro pressure instrument onboard the Phoenix Lander

    Harri, A.-M.; Polkko, J.; Kahanpää, H. H.; Schmidt, W.; Genzer, M. M.; Haukka, H.; Savijarv1, H.; Kauhanen, J.

    2009-04-01

    The Phoenix Lander landed successfully on the Martian northern polar region. The mission is part of the National Aeronautics and Space Administration's (NASA's) Scout program. Pressure observations onboard the Phoenix lander were performed by an FMI (Finnish Meteorological Institute) instrument, based on a silicon diaphragm sensor head manufactured by Vaisala Inc., combined with MDA data processing electronics. The pressure instrument performed successfully throughout the Phoenix mission. The pressure instrument had 3 pressure sensor heads. One of these was the primary sensor head and the other two were used for monitoring the condition of the primary sensor head during the mission. During the mission the primary sensor was read with a sampling interval of 2 s and the other two were read less frequently as a check of instrument health. The pressure sensor system had a real-time data-processing and calibration algorithm that allowed the removal of temperature dependent calibration effects. In the same manner as the temperature sensor, a total of 256 data records (8.53 min) were buffered and they could either be stored at full resolution, or processed to provide mean, standard deviation, maximum and minimum values for storage on the Phoenix Lander's Meteorological (MET) unit.The time constant was approximately 3s due to locational constraints and dust filtering requirements. Using algorithms compensating for the time constant effect the temporal resolution was good enough to detect pressure drops associated with the passage of nearby dust devils.

  2. Assessing Habitability: Lessons from the Phoenix Mission

    Stoker, Carol R.

    2013-01-01

    The Phoenix mission's key objective was to search for a habitable zone. The Phoenix lander carried a robotic arm with digging scoop to collect soil and icy material for analysis with an instrument payload that included volatile mineral and organic analysis(3) and soil ionic chemistry analysis (4). Results from Phoenix along with theoretical modeling and other previous mission results were used to evaluate the habitability of the landing site by considering four factors that characterize the environments ability to support life as we know it: the presence of liquid water, the presence of an energy source to support metabolism, the presence of nutrients containing the fundamental building blocks of life, and the absence of environmental conditions that are toxic to or preclude life. Phoenix observational evidence for the presence of liquid water (past or present) includes clean segregated ice, chemical etching of soil grains, calcite minerals in the soil and variable concentrations of soluble salts5. The maximum surface temperature measured was 260K so unfrozen water can form only in adsorbed films or saline brines but warmer climates occur cyclically on geologically short time scales due to variations in orbital parameters. During high obliquity periods, temperatures allowing metabolism extend nearly a meter into the subsurface. Phoenix discovered 1%w/w perchlorate salt in the soil, a chemical energy source utilized by a wide range of microbes. Nutrient sources including C, H, N, O, P and S compounds are supplied by known atmospheric sources or global dust. Environmental conditions are within growth tolerance for terrestrial microbes. Summer daytime temperatures are sufficient for metabolic activity, the pH is 7.8 and is well buffered and the projected water activity of a wet soil will allow growth. In summary, martian permafrost in the north polar region is a viable location for modern life. Stoker et al. presented a formalism for comparing the habitability of

  3. Phoenix Robotic Arm's Workspace After 90 Sols

    2008-01-01

    During the first 90 Martian days, or sols, after its May 25, 2008, landing on an arctic plain of Mars, NASA's Phoenix Mars Lander dug several trenches in the workspace reachable with the lander's robotic arm. The lander's Surface Stereo Imager camera recorded this view of the workspace on Sol 90, early afternoon local Mars time (overnight Aug. 25 to Aug. 26, 2008). The shadow of the the camera itself, atop its mast, is just left of the center of the image and roughly a third of a meter (one foot) wide. The workspace is on the north side of the lander. The trench just to the right of center is called 'Neverland.' The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  4. Digging Movie from Phoenix's Sol 18

    2008-01-01

    The Surface Stereo Imager on NASA's Phoenix Mars Lander recorded the images combined into this movie of the lander's Robotic Arm enlarging and combining the two trenches informally named 'Dodo' (left) and 'Goldilocks.' The 21 images in this sequence were taken over a period of about 2 hours during Phoenix's Sol 18 (June 13, 2008), or the 18th Martian day since landing. The main purpose of the Sol 18 dig was to dig deeper for learning the depth of a hard underlying layer. A bright layer, possibly ice, was increasingly exposed as the digging progressed. Further digging and scraping in the combined Dodo-Goldilocks trench was planned for subsequent sols. The combined trench is about 20 centimeters (about 8 inches) wide. The depth at the end of the Sol 18 digging is 5 to 6 centimeters (about 2 inches). The Goldilocks trench was the source of soil samples 'Baby Bear' and 'Mama Bear,' which were collected on earlier sols and delivered to instruments on the lander deck. The Dodo trench was originally dug for practice in collecting and depositing soil samples. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  5. 'Dodo-Goldilocks' Trench Dug by Phoenix

    2008-01-01

    This color image was acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager on the 19th day of the mission, or Sol 19 (June 13, 2008), after the May 25, 2008, landing. This image shows one trench informally called 'Dodo-Goldilocks' after two digs (dug on Sol 18, or June 12, 2008) by Phoenix's Robotic Arm. The trench is 22 centimeters (8.7 inches) wide and 35 centimeters (13.8 inches) long. At its deepest point, the trench is 7 to 8 centimeters (2.7 to 3 inches) deep. White material, possibly ice, is located only at the upper portion of the trench, indicating that it is not continuous throughout the excavated site. According to scientists, the trench might be exposing a ledge, or only a portion of a slab, of the white material. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  6. Correlation between the surface chemistry and the atmospheric corrosion of AZ31, AZ80 and AZ91D magnesium alloys

    Feliu, S.; Pardo, A.; Merino, M.C.; Coy, A.E.; Viejo, F.; Arrabal, R.

    2009-01-01

    X-ray photoelectron spectroscopy (XPS) was used in order to investigate the correlation between the surface chemistry and the atmospheric corrosion of AZ31, AZ80 and AZ91D magnesium alloys exposed to 98% relative humidity at 50 deg. C. Commercially pure magnesium, used as the reference material, revealed MgO, Mg(OH) 2 and tracers of magnesium carbonate in the air-formed film. For the AZ80 and AZ91D alloys, the amount of magnesium carbonate formed on the surface reached similar values to those of MgO and Mg(OH) 2 . A linear relation between the amount of magnesium carbonate formed on the surface and the subsequent corrosion behaviour in the humid environment was found. The AZ80 alloy revealed the highest amount of magnesium carbonate in the air-formed film and the highest atmospheric corrosion resistance, even higher than the AZ91D alloy, indicating that aluminium distribution in the alloy microstructure influenced the amount of magnesium carbonate formed.

  7. Decontamination sheet

    Hirose, Emiko; Kanesaki, Ken.

    1995-01-01

    The decontamination sheet of the present invention is formed by applying an adhesive on one surface of a polymer sheet and releasably appending a plurality of curing sheets. In addition, perforated lines are formed on the sheet, and a decontaminating agent is incorporated in the adhesive. This can reduce the number of curing operation steps when a plurality steps of operations for radiation decontamination equipments are performed, and further, the amount of wastes of the cured sheets, and operator's exposure are reduced, as well as an efficiency of the curing operation can be improved, and propagation of contamination can be prevented. (T.M.)

  8. Nano grained AZ31 alloy achieved by equal channel angular rolling process

    Hassani, F.Z.; Ketabchi, M.

    2011-01-01

    Equal channel angular rolling (ECAR) is a severe plastic deformation process which is carried out on large, thin sheets. The grain size could be significantly decreased by this process. The main purpose of this study is to investigate the possibility of grain refinement of AZ31 magnesium alloy sheet by this process to nanometer. The effect of the number of ECAR passes on texture evolution of AZ31 magnesium alloy was investigated. ECAR temperature was controlled to maximize the grain refinement efficiency along with preventing cracking. The initial microstructure of as-received AZ31 sheet showed an average grain size of about 21 μm. The amount of grain refinement increased with increasing the pass number. After 10 passes of the process, significant grain refinement occurred and the field emission scanning electron microscopic (FESEM) micrographs showed that the size of grains were decreased significantly to about 14-70 nm. These grains were formed at the grain boundaries and inside some of the previous larger micrometer grains. Observation of optical microstructures and X-ray diffraction patterns (XRD) showed the formation of twins after ECAR process. Micro-hardness of material was studied at room temperature. There was a continuous enhancement of hardness by increasing the pass number of ECAR process. At the 8th pass, hardness values increased by 53%. At final passes hardness reduced slightly, which was attributed to saturation of strain in high number of passes.

  9. A Comparative Electrochemical Study of AZ31 and AZ91 Magnesium Alloy

    S. A. Salman

    2010-01-01

    Full Text Available A comparative study has been carried out on AZ31 and AZ91 magnesium alloys in order to understand the electrochemical behavior in both alkaline and chloride containing solutions. The open circuit potential (OCP was examined in 1 M NaOH and 3.5 mass % NaCl solutions. AZ31 magnesium alloy shows several potential drops throughout the immersion in 1 M NaOH solution, though AZ91 does not show this phenomenon. The specimens were anodized at a constant potential of 3 V for 30 minutes at 298 K in 1 M NaOH solution. The anticorrosion behavior of the anodized specimens was better than those of nonanodized specimens. The anodized AZ91 has better corrosion resistance compared to nonanodized specimen and anodized AZ31 magnesium alloy.

  10. Comparison of some Phoenix and gusev soil types

    Walter..[], Goetz; Hviid, S.F.; Madsen, Morten Bo

    2010-01-01

    The comparison of soil particles at the Phoenix landing site and in Gusev Crater provides clues on their origin and global distribution. Some unusual Phoenix particles are possibly of (more) local origin, as they appear to be absent in Gusev dunes....

  11. The A-Z of electronuclear power

    Temmerman, G. de; Chedorge, D.

    1992-01-01

    Both a bilingual translation aid and a reference book, 'The A-Z of Electronuclear Power' covers the full range of electronuclear activities and the English and French terminology relating to the different phases of the modern industrial process

  12. Cold-Sprayed AZ91D Coating and SiC/AZ91D Composite Coatings

    Yingying Wang

    2018-03-01

    Full Text Available As an emerging coating building technique, cold spraying has many advantages to elaborate Mg alloy workpieces. In this study, AZ91D coatings and AZ91D-based composite coatings were deposited using cold spraying. Coatings were prepared using different gas temperatures to obtain the available main gas temperature. Compressed air was used as the accelerating gas, and although magnesium alloy is oxidation-sensitive, AZ91D coatings with good performance were obtained. The results show that dense coatings can be fabricated until the gas temperature is higher than 500 °C. The deposition efficiency increases greatly with the gas temperature, but it is lower than 10% for all coating specimens. To analyze the effects of compressed air on AZ91D powder particles and the effects of gas temperature on coatings, the phase composition, porosity, cross-sectional microstructure, and microhardness of coatings were characterized. X-ray diffraction and oxygen content analysis clarified that no phase transformation or oxidation occurred on AZ91D powder particles during cold spraying processes with compressed air. The porosity of AZ91D coatings remained between 3.6% and 3.9%. Impact melting was found on deformed AZ91D particles when the gas temperature increased to 550 °C. As-sprayed coatings exhibit much higher microhardness than as-casted bulk magnesium, demonstrating the dense structure of cold-sprayed coatings. To study the effects of ceramic particles on cold-sprayed AZ91D coatings, 15 vol % SiC powder particles were added into the feedstock powder. Lower SiC content in the coating than in the feedstock powder means that the deposition efficiency of the SiC powder particles is lower than the deposition efficiency of AZ91D particles. The addition of SiC particles reduces the porosity and increases the microhardness of cold-sprayed AZ91D coatings. The corrosion behavior of AZ91D coating and SiC reinforced AZ91D composite coating were examined. The Si

  13. The Phoenix Mars Lander Robotic Arm

    Bonitz, Robert; Shiraishi, Lori; Robinson, Matthew; Carsten, Joseph; Volpe, Richard; Trebi-Ollennu, Ashitey; Arvidson, Raymond E.; Chu, P. C.; Wilson, J. J.; Davis, K. R.

    2009-01-01

    The Phoenix Mars Lander Robotic Arm (RA) has operated for over 150 sols since the Lander touched down on the north polar region of Mars on May 25, 2008. During its mission it has dug numerous trenches in the Martian regolith, acquired samples of Martian dry and icy soil, and delivered them to the Thermal Evolved Gas Analyzer (TEGA) and the Microscopy, Electrochemistry, and Conductivity Analyzer (MECA). The RA inserted the Thermal and Electrical Conductivity Probe (TECP) into the Martian regolith and positioned it at various heights above the surface for relative humidity measurements. The RA was used to point the Robotic Arm Camera to take images of the surface, trenches, samples within the scoop, and other objects of scientific interest within its workspace. Data from the RA sensors during trenching, scraping, and trench cave-in experiments have been used to infer mechanical properties of the Martian soil. This paper describes the design and operations of the RA as a critical component of the Phoenix Mars Lander necessary to achieve the scientific goals of the mission.

  14. Vertical Distribution of Water at Phoenix

    Tamppari, L. K.; Lemmon, M. T.

    2011-01-01

    Phoenix results, combined with coordinated observations from the Mars Reconnaissance Orbiter of the Phoenix lander site, indicate that the water vapor is nonuniform (i.e., not well mixed) up to a calculated cloud condensation level. It is important to understand the mixing profile of water vapor because (a) the assumption of a well-mixed atmosphere up to a cloud condensation level is common in retrievals of column water abundances which are in turn used to understand the seasonal and interannual behavior of water, (b) there is a long history of observations and modeling that conclude both that water vapor is and is not well-mixed, and some studies indicate that the water vapor vertical mixing profile may, in fact, change with season and location, (c) the water vapor in the lowest part of the atmosphere is the reservoir that can exchange with the regolith and higher amounts may have an impact on the surface chemistry, and (d) greater water vapor abundances close to the surface may enhance surface exchange thereby reducing regional transport, which in turn has implications to the net transport of water vapor over seasonal and annual timescales.

  15. Power lines Phoenix and the making of the modern southwest

    Needham, Andrew

    2014-01-01

    In 1940, Phoenix was a small, agricultural city of sixty-five thousand, and the Navajo Reservation was an open landscape of scattered sheepherders. Forty years later, Phoenix had blossomed into a metropolis of 1.5 million people and the territory of the Navajo Nation was home to two of the largest strip mines in the world. Five coal-burning power plants surrounded the reservation, generating electricity for export to Phoenix, Los Angeles, and other cities. Exploring the postwar developments of these two very different landscapes, Power Lines tells the story of the far-reaching environmental a

  16. Project Phoenix and beyond. Pesek Lecture.

    Tarter, J

    1997-01-01

    Although there are no federally funded projects at this time, SETI (the search for extraterrestrial intelligence) is a vigorous exploratory science. There are currently eight observational programs on telescopes around the world, of which the Phoenix Project is the most comprehensive. Most of these projects are rooted in the conclusions of the pioneering studies of the early 1970's that are summarized in the Cyclops Report. Technology has experienced an exponential growth over the past two and a half decades. It is reasonable to reassess the Cyclops conclusions as SETI enters the next century. Listening for radio signals is still the preferred method of searching, however new technologies are making searches at other wavelengths possible and are modifying the ways in which the radio searches can and should be conducted. It may be economically feasible to undertake the construction of very large telescopes that can simultaneously provide multiple beams on the sky for use by SETI and the radioastronomy community.

  17. Pesek lecture project Phoenix and beyond

    Tarter, Jill

    Although there are no federally funded projects at this time, SETI (the search for extraterrestrial intelligence) is a vigorous exploratory science. There are currently eight observational programs on telescopes around the world, of which the Phoenix Project is the most comprehensive. Most of these projects are rooted in the conclusions of the pioneering studies of the early 1970's that are summarized in the Cyclops Report1. Technology has experienced an exponential growth over the past two and a half decades. It is reasonable to reassess the Cyclops conclusions as SETI enters the next century. Listening for radio signals is still the preferred method of searching, however new technologies are making searches at other wavelengths possible and are modifying the ways in which the radio searches can and should be conducted. It may be economically feasible to undertake the construction of very large telescopes that can simultaneously provide multiple beams on the sky for use by SETI and the radioastronomy community.

  18. CRED REA Coral Population Parameters at Baker, Phoenix Islands, 2004

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 3 sites at Baker in the Phoenix...

  19. Telecommunications Relay Support of the Mars Phoenix Lander Mission

    Edwards, Charles D., Jr.; Erickson, James K.; Gladden, Roy E.; Guinn, Joseph R.; Ilott, Peter A.; Jai, Benhan; Johnston, Martin D.; Kornfeld, Richard P.; Martin-Mur, Tomas J.; McSmith, Gaylon W.; hide

    2010-01-01

    The Phoenix Lander, first of NASA's Mars Scout missions, arrived at the Red Planet on May 25, 2008. From the moment the lander separated from its interplanetary cruise stage shortly before entry, the spacecraft could no longer communicate directly with Earth, and was instead entirely dependent on UHF relay communications via an international network of orbiting Mars spacecraft, including NASA's 2001 Mars Odyssey (ODY) and Mars Reconnaissance Orbiter (MRO) spacecraft, as well as ESA's Mars Express (MEX) spacecraft. All three orbiters captured critical event telemetry and/or tracking data during Phoenix Entry, Descent and Landing. During the Phoenix surface mission, ODY and MRO provided command and telemetry services, far surpassing the original data return requirements. The availability of MEX as a backup relay asset enhanced the robustness of the surface relay plan. In addition to telecommunications services, Doppler tracking observables acquired on the UHF link yielded an accurate position for the Phoenix landing site.

  20. Commissioning of Theratron phoenix telecobalt machine and its performance assessment

    Rajendran, M.; Reddy, K.D.; Reddy, R.M.; Reddy, J.M.; Reddy, B.V.N.; Kumar, K.; Gopi, S.; Rajan, Dharani; Janardhanan

    2002-01-01

    Teletherapy machines like cobalt-60 unit and linear accelerator are extensively used for radiotherapy. Theratron phoenix machines have been installed. A brief report on the performance of this machine is presented

  1. Corrosion behavior of friction stir welded AZ31B Mg alloy - Al6063 alloy joint

    B. Ratna Sunil

    2016-12-01

    Full Text Available In the present work, AZ31B Mg alloy and Al6063 alloy-rolled sheets were successfully joined by friction stir welding. Microstructural studies revealed a sound joint with good mechanical mixing of both the alloys at the nugget zone. Corrosion performance of the joint was assessed by immersing in 3.5% NaCl solution for different intervals of time and the corrosion rate was calculated. The joint has undergone severe corrosion attack compared with both the base materials (AZ31B and Al6063 alloys. The predominant corrosion mechanism behind the high corrosion rate of the joint was found to be high galvanic corrosion. From the results, it can be suggested that the severe corrosion of dissimilar Mg–Al joints must be considered as a valid input while designing structures intended to work in corroding environment.

  2. Manufacturing and Design Engineering Students St. Mary's Hospital, Phoenix Park.

    Mitchell, Leah

    2012-01-01

    Poster with details of project to improve ease of movement for Kirton Stirling chairs in St. Mary's Hospital, Phoenix Park, Dublin. Third year students in the B Eng (Honours) Manufacturing and Design Engineering course at Bolton St. completed a project in conjunction with St. Mary‟s Hospital, Phoenix Park. The staff in St Mary‟s were experiencing difficulty in moving the Kirton Stirling chairs (pictured above). These chairs are used to transport elderly patients from one location to another. ...

  3. 77 FR 10649 - Modification of Class E Airspace; Douglas, AZ

    2012-02-23

    ...-1313; Airspace Docket No. 11-AWP-17] Modification of Class E Airspace; Douglas, AZ AGENCY: Federal... Bisbee Douglas International Airport, Douglas, AZ. Decommissioning of the Cochise VHF Omni-Directional... Federal Register a notice of proposed rulemaking to amend controlled airspace at Douglas, AZ (76 FR 78180...

  4. Tank 241-AZ-101 tank characterization plan

    Schreiber, R.D.

    1995-01-01

    The Defense Nuclear Facilities Safety Board has advised the DOE to concentrate the near-term sampling and analysis activities on identification and resolution of safety issues. The Data Quality Objective (DQO) process was chosen as a tool to be used in the resolution of safety issues. As a result, A revision in the Federal Facilities Agreement and Consent Order (Tri-Party Agreement) milestone M-44 has been made, which states that ''A Tank Characterization Plan (TCP) will also be developed for each double-shell tank (DST) and single-shell tank (SST) using the DQO process. Development of TCPs by the DQO process is intended to allow users to ensure their needs will be met and that resources are devoted to gaining only necessary information''. This document satisfies that requirement for Tank 241-AZ-101 (AZ-101) sampling activities. Tank AZ-101 is currently a non-Watch List tank, so the only DQOs applicable to this tank are the safety screening DQO and the compatibility DQO, as described below. The contents of Tank AZ-101, as of October 31, 1994, consisted of 3,630 kL (960 kgal) of dilute non-complexed waste and aging waste from PUREX (NCAW, neutralized current acid waste). Tank AZ-101 is expected to have two primary layers. The bottom layer is composed of 132 kL of sludge, and the top layer is composed of 3,500 kL of supernatant, with a total tank waste depth of approximately 8.87 meters

  5. Tank 241-AZ-102 tank characterization plan

    Schreiber, R.D.

    1995-01-01

    The Defense Nuclear Facilities Safety Board has advised the DOE to concentrate the near-term sampling and analysis activities on identification and resolution of safety issues. The Data Quality Objective (DQO) process was chosen as a tool to be used in the resolution of safety issues. As a result, a revision in the Federal Facilities Agreement and Consent Order (Tri-Party Agreement) milestone M-44 has been made, which states that ''A Tank Characterization Plan (TCP) will also be developed for each double-shell tank (DST) and single-shell tank (SST) using the DQO process ... Development of TCPs by the DQO process is intended to allow users to ensure their needs will be met and that resources are devoted to gaining only necessary information''. This document satisfies that requirement for tank 241-AZ-102 (AZ-102) sampling activities. Tank AZ-102 is currently a non-Watch List tank, so the only DQOs applicable to this tank are the safety screening DQO and the compatibility DQO, as described below. The current contents of Tank AZ-102, as of October 31, 1994, consisted of 3,600 kL (950 kgal) of dilute non-complexed waste and aging waste from PUREX (NCAW, neutralized current acid waste). Tank AZ-102 is expected to have two primary layers. The bottom layer is composed of 360 kL of sludge, and the top layer is composed of 3,240 kL of supernatant, with a total tank waste depth of approximately 8.9 meters

  6. Structure and Mechanical Properties of Friction Stir Weld Joints of Magnesium Alloy AZ31

    Nagasawa, T.; Otsuka, M.; Yokota, T.; Ueki, T.

    The applicability of friction stir welding to hot rolled sheet of commercial magnesium alloy AZ31 plates has been investigated. Friction stir weld joint showed mechanical strength comparable to that of base material, though the ductility remained at one half of that of the latter. The results are consistent with the microstructure which is characterized by a fine grained bond layer bounded by-intermediate grained base metals. It is found that both anodizing treatment and insertion of aluminum foil between batting faces do not degrade the joint properties at all. The results suggest that friction stir welding can be potentially applied to magnesium alloy.

  7. Troubles continue for the Phoenix VA

    Robbins RA

    2014-10-01

    Full Text Available No abstract available. Article truncated after 150 words. According to the Joint Commission on the Accreditation of Healthcare Organizations (Joint Commission, JCAHO, an independent organization that reviews hospitals, the Phoenix VA does not comply with U.S. standards for safety, patient care and management (1. The hospital was at the epicenter of the national scandal over the quality of care being afforded to the nation's veterans where the now notorious practice of double-booking patient appointments was first exposed. The hospital's indifferent management provoked congressional investigations that uncovered still more system-wide abuses leading to the removal of the hospital director and the resignation of then VA secretary, Eric Shinseki. The hospital maintains its accreditation but with a follow-up survey in 1-6 months where it must show that it has successfully addressed the 13 identified problems (1. Inspectors who conducted the review in July found that VA employees were unable to report concerns "without retaliatory action from the hospital." Other alarming ...

  8. Ovate pontics: Phoenixing the gingival contour

    Medha Vivek Bhuskute

    2017-01-01

    Full Text Available In today's busy world, most patients do not have time for long, drawn-out dental treatment. The time span between extraction and healing after loss of tooth in the anterior esthetic zone can be esthetically and psychologically devastating on the part of the patient. Especially, when a maxillary anterior tooth must be extracted and replaced, immediate tooth replacement with an ovate pontic on a provisional bridge is a good alternative. Ovate pontic helps in preservation of the interdental papilla, which in turn preserves the natural gingival contour that would have otherwise been lost after extraction. An immediate tooth replacement using ovate pontic not only eliminates the psychologically disturbing partially edentulous phase but also results in a much more esthetically pleasing replacement of tooth that is both hygienic and natural in appearance. Another added advantage of the use of ovate pontic is that it rules out the dissatisfaction resulting from an unesthetic ridge lap pontic placed directly over edentulous ridge. Just like the long-lived bird “Phoenix,” arising out of its own ashes, the ovate pontic creates an illusion that the pontic is emerging from the gingiva, even after tooth loss. This case report discusses how an integrated approach of fabricating heat cure provisional bridge with ovate pontics before extractions, benefitted a young patient in whom fractured anterior teeth were proposed for extraction.

  9. EnviroAtlas - Phoenix, AZ - Domestic Water Demand per Day by U.S. Census Block Group

    U.S. Environmental Protection Agency — As included in this EnviroAtlas dataset, community level domestic water demand is calculated using locally available water use data per capita in gallons of water...

  10. Characteristics of AZ31 Mg alloy joint using automatic TIG welding

    Liu, Hong-tao; Zhou, Ji-xue; Zhao, Dong-qing; Liu, Yun-teng; Wu, Jian-hua; Yang, Yuan-sheng; Ma, Bai-chang; Zhuang, Hai-hua

    2017-01-01

    The automatic tungsten-inert gas welding (ATIGW) of AZ31 Mg alloys was performed using a six-axis robot. The evolution of the microstructure and texture of the AZ31 auto-welded joints was studied by optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and electron backscatter diffraction. The ATIGW process resulted in coarse recrystallized grains in the heat affected zone (HAZ) and epitaxial growth of columnar grains in the fusion zone (FZ). Substantial changes of texture between the base material (BM) and the FZ were detected. The {0002} basal plane in the BM was largely parallel to the sheet rolling plane, whereas the c-axis of the crystal lattice in the FZ inclined approximately 25° with respect to the welding direction. The maximum pole density increased from 9.45 in the BM to 12.9 in the FZ. The microhardness distribution, tensile properties, and fracture features of the AZ31 auto-welded joints were also investigated.

  11. 75 FR 17692 - Foreign-Trade Zone 75 -- Phoenix, Arizona, Application for Reorganization under Alternative Site...

    2010-04-07

    ...'' in the context of the Board's standard 2,000-acre activation limit for a general-purpose zone project... terminal at the Phoenix Sky Harbor International Airport, Phoenix; Site 2 (18 acres) CC&F South Valley..., 4747 West Buckeye Road, Phoenix; Site 4 (18 acres) - Santa Fe Business Park, 47th Avenue and Campbell...

  12. Animation of Panorama of Phoenix's Solar Panel and Robotic Arm

    2008-01-01

    [figure removed for brevity, see original site] Click on image for animation This is an animation of panorama images of NASA's Phoenix Mars Lander's solar panel and the lander's Robotic Arm with a sample in the scoop. The image was taken just before the sample was delivered to the Optical Microscope. The images making up this animation were taken by the lander's Surface Stereo Imager looking west during Phoenix's Sol 16 (June 10, 2008), or the 16th Martian day after landing. This view is a part of the 'mission success' panorama that will show the whole landing site in color. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  13. Friction welding of AZ31 magnesium alloy

    Tsujino, R.; Ochi, H. [Osaka Inst. of Tech., Osaka (Japan); Kawai, G. [Osaka Sangyo Univ., Osaka (Japan); Yamaguchi, H.; Ogawa, K. [Osaka Prefecture Univ., Osaka (Japan); Suga, Y. [Keio Univ., Kanagawa (Japan)

    2003-07-01

    In this paper, for an acceleration of utilization of magnesium alloy which is being interested in recent years, friction welding of AZ31 magnesium alloy was carried out, and the joint performance was discussed in relation to the deformation heat input in the upset stage and upset loss as a evaluation factor. Where, the deformation heat input in the upset stage is mechanical work represented by the product of upset speed and axial pressure. As a result, it was made clear that the friction welding of AZ31 magnesium alloy was easy in the atmosphere, and good welded joints without a non- adhesion area at the weld interface could de obtained. Moreover, the evaluation factors discussed were possible to evaluate to joint performance. (orig.)

  14. Mathematical modeling of the Phoenix Rising pathway.

    Chad Liu

    2014-02-01

    Full Text Available Apoptosis is a tightly controlled process in mammalian cells. It is important for embryogenesis, tissue homoeostasis, and cancer treatment. Apoptosis not only induces cell death, but also leads to the release of signals that promote rapid proliferation of surrounding cells through the Phoenix Rising (PR pathway. To quantitatively understand the kinetics of interactions of different molecules in this pathway, we developed a mathematical model to simulate the effects of various changes in the PR pathway on the secretion of prostaglandin E2 (PGE2, a key factor for promoting cell proliferation. These changes include activation of caspase 3 (C3, caspase 7 (C7, and nuclear factor κB (NFκB. In addition, we simulated the effects of cyclooxygenase-2 (COX2 inhibition and C3 knockout on the level of secreted PGE2. The model predictions on PGE2 in MEF and 4T1 cells at 48 hours after 10-Gray radiation were quantitatively consistent with the experimental data in the literature. Compared to C7, the model predicted that C3 activation was more critical for PGE2 production. The model also predicted that PGE2 production could be significantly reduced when COX2 expression was blocked via either NFκB inactivation or treatment of cells with exogenous COX2 inhibitors, which led to a decrease in the rate of conversion from arachidonic acid to prostaglandin H2 in the PR pathway. In conclusion, the mathematical model developed in this study yielded new insights into the process of tissue regrowth stimulated by signals from apoptotic cells. In future studies, the model can be used for experimental data analysis and assisting development of novel strategies/drugs for improving cancer treatment or normal tissue regeneration.

  15. Dinosaur or Phoenix: Nuclear Bombers in the 21st Century

    2010-04-12

    REPORT DATE 02-04-10 2. REPORT TYPE Master’s Thesis 3. DATES COVERED 31-07-09 to 16-06-10 4. TITLE AND SUBTITLE Dinosaur or Phoenix: Nuclear...WARFIGHTING SCHOOL DINOSAUR OR PHOENIX: NUCLEAR BOMBERS IN THE 21ST CENTURY by John W. Morehead Colonel, United States Air Force A paper...can argue Secretary Gates’ decision to halt development of a follow-on bomber indicates the DOD views nuclear bombers as dinosaurs no longer needed as

  16. Microstructure of AZ31 Magnesium Alloy deformed by indentation-flattening compound deformation technology

    Wang, Minghao; Wang, Zhongtang; Yu, Xiaolin

    2018-03-01

    Characteristic of indentation-flattening compound deformation technology (IFCDT) is discussed, and the parameters of IFCDT are defined. Performance of magnesium alloy AZ31 sheet deformed by IFCDT is researched. The effect of IFCDT coefficient, temperature and reduction ratio on the microstructure of magnesium alloy sheet is analyzed. The research results show that the volume fraction of the twin crystal decreases gradually and the average grain size increases with increasing of coefficient of IFCDT. With increase of the reduction ratio, the volume fraction of the twin crystal gradually increases, and the average grain size also increases. With increase of deformation temperature, the volume fraction of the twin crystal decreases gradually, and the twin crystal grain size increases.

  17. Corrosion product layers on magnesium alloys AZ31 and AZ61: Surface chemistry and protective ability

    Feliu, S.; Llorente, I.

    2015-08-01

    This paper studies the chemical composition of the corrosion product layers formed on magnesium alloys AZ31 and AZ61 following immersion in 0.6 M NaCl, with a view to better understanding their protective action. Relative differences in the chemical nature of the layers were quantified by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDX) and low-angle X-ray diffraction (XRD). Corrosion behavior was investigated by Electrochemical Impedance Spectroscopy (EIS) and hydrogen evolution measurement. An inhibitive effect from the corrosion product layers was observed from EIS, principally in the case of AZ31, as confirmed by hydrogen evolution tests. A link was found between carbonate enrichment observed by XPS in the surface of the corrosion product layer, concomitant with the increase in the protective properties observed by EIS.

  18. Study of deformation texture in an AZ31 magnesium alloy rolled at wide range of rolling speed and reductions

    Sanjari, M; Su, J; Kabir, A S; Yue, S; Tamimi, S; Hara, K; Utsunomiya, H; Petrov, R; Kestens, L

    2015-01-01

    The plasticity of Mg is restricted at low temperatures because: (a) only a small number of deformation mechanisms can be activated, and (b) a preferred crystallographic orientation (texture) develops in wrought alloys, especially in flat-rolled sheets. This causes problems in thin sheet processing as well as component manufacturing from the sheet. In this study, different rolling speeds from 15 to 1000 m/min were employed to warm-roll AZ31B magnesium alloy to different reductions. The results show that AZ31B sheets rolled at 15 m/min and 100 °C has fractured for reductions of more than 30% per pass. However, by increasing the rolling speed to 1000 m/min the rollability was improved significantly and the material can be rolled to reductions of more than 70% per pass. The results show that with increasing strain rate at 100°C, the splitting of basal poles was observed, indicating the activation of more contraction twins and secondary twins. (paper)

  19. Thermophysical Properties of the Phoenix Mars Landing Site Study Regions

    Putzig, N. E.; Mellon, M. T.; Golombek, M. P.; Arvidson, R. E.

    2006-03-01

    Analysis of Phoenix Mars study regions places 4 of 5 in a previously-identified duricrust-dominated thermophysical unit which also contains the Viking and Spirit landing sites. Extrapolation of lander-observed properties to the study regions may be complicated by surface heterogeneity.

  20. The Phoenix galaxy as seen by NuSTAR

    Masini, A.; Comastri, A.; Puccetti, S.

    2017-01-01

    Aims. We study the long-term variability of the well-known Seyfert 2 galaxy Mrk 1210 (also known as UGC 4203, or the Phoenix galaxy). Methods. The source was observed by many X-ray facilities in the last 20 yr. Here we present a NuSTAR observation and put the results in the context of previously ...

  1. The Flight of the Phoenix: Interpersonal Aspects of Project Management

    Huffman, Brian J.; Kilian, Claire McCarty

    2012-01-01

    Although many classroom exercises use movies to focus on management and organizational behavior issues, none of those do so in the context of project management. This article presents such an exercise using "The Flight of the Phoenix", an incredibly rich story for any management class, which provides clear examples of organizational behavior…

  2. Assessment of genetic diversity for some Iraqi date palms ( Phoenix ...

    Amplified fragment length polymorphisms (AFLP) were used to evaluate the genetic diversity between 18 date palm (Phoenix dactylifera L.) varieties (11 females and 7 males) collected from the center of Iraq. Six primer pairs were applied to detect polymorphism between varieties. A total of 83 polymorphic AFLP fragments ...

  3. Gender Roles in Chika Unigwe's The Phoenix | Akani | African ...

    This paper examines gender roles in Chika Unigwe's The Phoenix (2007). In examining these gender roles, the paper focuses on the roles of both female and male genders in the novel in order to tease out issues that border on the marriage institution and gender complementarity in a multicultural setting. As we have ...

  4. Telltale wind indicator for the Mars Phoenix lander

    Gunnlaugsson, H.P.; Honstein-Rathlou, C.; Merrison, J.P.

    2008-01-01

    The Telltale wind indicator is a mechanical anemometer designed to operate on the Martian surface as part of the meteorological package on the NASA Phoenix lander. It consists of a lightweight cylinder suspended by Kevlar fibers and is deflected under the action of wind. Imaging of the Telltale...

  5. Ethnobotanical survey of Phoenix dactylifera L. Pollen used for the ...

    Background: The Phoenix dactylifera L. (date palm) is known for its traditional medicinal properties across the history of native population in Algerian Sahara. There is a large trend of consumption of date palm pollen preparations in many human infertility cases in our country. However, the validity has not been scientifically ...

  6. 75 FR 57327 - Environmental Impact Statement; Pinal County, AZ

    2010-09-20

    ...: Kenneth H. Davis, Senior Engineering Manager for Operations, Federal Highway Administration, 4000 N... Conservation Service, Federal Aviation Administration, Federal Transit Administration, U.S. Department of... Engineering Manager for Operations, Federal Highway Administration, Arizona Division Office, Phoenix, Arizona...

  7. Tank 241-AZ-101 and tank 241-AZ-102, airlift circulator operation vapor sampling and analysis plan

    TEMPLETON, A.M.

    1999-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for vapor samples obtained during the operation of the tank 241-AZ-101 and 241-AZ-102 airlift circulators (ALCs). The purpose of the ALC operation is to support portions of the operational test procedure (OTP) for Project W-030 (OTP-W030-001) and to perform functional test in support of Project W-151. Project W-030 is the 241-A-702 ventilation upgrade project (241-AZ-702) and Project W-151 is the 241-AZ-101 Mixer Pump Test. The functional tests will check the operability of the tank 241-AZ-101 ALCs. Process Memo's No.2E98-082 and No.2E99-001 (LMHC 1999a, LMHC 1999b) direct the operation of the ALCs and the Industrial Hygiene monitoring respectively. A series of tests will be conducted in which the ALCs in tanks 241-AZ-101 and 241-AZ-102 will be operated at different air flow rates. Vapor samples will be obtained to determine constituents that may be present in the tank headspace during ALC operation at tanks 241-AZ-101 and 241-AZ-102 as the waste is disturbed. During the testing, vapor samples will be obtained from the headspace of tanks 241-AZ-101 and 241-AZ-102 via the unused port on the standard hydrogen monitoring system (SHMS). Results will be used to provide the waste feed delivery program with environmental air permitting data for tank waste disturbing activities. Because of radiological concerns, the samples will be filtered for particulates. It is recognized that this may remove some organic compounds

  8. Grain refinement of AZ31 magnesium alloy by electromagnetic ...

    Low-frequency electromagnetic field; AZ31 magnesium alloy; Al4C3; grain refinement. Abstract. The effects of electromagnetic stirring and Al4C3 grain refiner on the grain refinement of semicontinuously cast AZ31 magnesium alloy were discussed in this investigation. The results indicate that electromagnetic stirring has an ...

  9. ANALYSIS RESULTS FOR BUILDING 241 702-AZ A TRAIN

    DUNCAN JB; FRYE JM; COOKE CA; LI SW; BROCKMAN FJ

    2006-12-13

    This report presents the analyses results for three samples obtained under RPP-PLAN-28509, Sampling and Analysis Plan for Building 241 702-AZ A Train. The sampling and analysis was done in response to problem evaluation request number PER-2004-6139, 702-AZ Filter Rooms Need Radiological Cleanup Efforts.

  10. 76 FR 18378 - Amendment of Class E Airspace; Taylor, AZ

    2011-04-04

    ...-1189; Airspace Docket No. 10-AWP-19] Amendment of Class E Airspace; Taylor, AZ AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action will amend Class E airspace at Taylor Airport, Taylor, AZ, to accommodate aircraft using the CAMBO One Departure, and the Area Navigation (RNAV...

  11. ANALYSIS RESULTS FOR BUILDING 241 702-AZ A TRAIN

    DUNCAN JB; FRYE JM; COOKE CA; LI SW; BROCKMAN FJ

    2006-01-01

    This report presents the analyses results for three samples obtained under RPP-PLAN-28509, Sampling and Analysis Plan for Building 241 702-AZ A Train. The sampling and analysis was done in response to problem evaluation request number PER-2004-6139, 702-AZ Filter Rooms Need Radiological Cleanup Efforts

  12. 702AZ aging waste ventilation facility year 2000 test procedure

    Winkelman, W.D.

    1998-01-01

    This test procedure was developed to determine if the 702AZ Tank Ventilation Facility system is Year 2000 Compliant. The procedure provides detailed instructions for performing the operations necessary and documenting the results. This verification procedure will document that the 702AZ Facility Systems are year 2000 compliant and will correctly meet the criteria established in this procedure

  13. Census Cities experiment in urban change detection. [mapping of land use changes in San Francisco, Washington D.C., Phoenix, Tucson, Boston, New Haven, Cedar Rapids, and Pontiac

    Wray, J. R. (Principal Investigator); Milazzo, V. A.

    1974-01-01

    The author has identified the following significant results. Mapping of 1970 and 1972 land use from high-flight photography has been completed for all test sites: San Francisco, Washington, Phoenix, Tucson, Boston, New Haven, Cedar Rapids, and Pontiac. Area analysis of 1970 and 1972 land use has been completed for each of the mandatory urban areas. All 44 sections of the 1970 land use maps of the San Francisco test site have been officially released through USGS Open File at 1:62,500. Five thousand copies of the Washington one-sheet color 1970 land use map, census tract map, and point line identification map are being printed by USGS Publication Division. ERTS-1 imagery for each of the eight test sites is being received and analyzed. Color infrared photo enlargements at 1:100,000 of ERTS-1 MSS images of Phoenix taken on October 16, 1972 and May 2, 1973 are being analyzed to determine to what level land use and land use changes can be identified and to what extent the ERTS-1 imagery can be used in updating the 1970 aircraft photo-derived land use data base. Work is proceeding on the analysis of ERTS-1 imagery by computer manipulation of ERTS-1 MSS data in digital format. ERTS-1 CCT maps at 1:24,000 are being analyzed for two dates over Washington and Phoenix. Anniversary tape sets have been received at Purdue LARS for some additional urban test sites.

  14. Chlamydia - CDC Fact Sheet

    ... Archive STDs Home Page Bacterial Vaginosis (BV) Chlamydia Gonorrhea Genital Herpes Hepatitis HIV/AIDS & STDs Human Papillomavirus ( ... sheet Pelvic Inflammatory Disease (PID) – CDC fact sheet Gonorrhea – CDC fact sheet STDs Home Page Bacterial Vaginosis ( ...

  15. GASN sheets

    2013-12-01

    This document gathers around 50 detailed sheets which describe and present various aspects, data and information related to the nuclear sector or, more generally to energy. The following items are addressed: natural and artificial radioactive environment, evolution of energy needs in the world, radioactive wastes, which energy for France tomorrow, the consequences in France of the Chernobyl accident, ammunitions containing depleted uranium, processing and recycling of used nuclear fuel, transport of radioactive materials, seismic risk for the basic nuclear installations, radon, the precautionary principle, the issue of low doses, the EPR, the greenhouse effect, the Oklo nuclear reactors, ITER on the way towards fusion reactors, simulation and nuclear deterrence, crisis management in the nuclear field, does nuclear research put a break on the development of renewable energies by monopolizing funding, nuclear safety and security, the plutonium, generation IV reactors, comparison of different modes of electricity production, medical exposure to ionizing radiations, the control of nuclear activities, food preservation by ionization, photovoltaic solar collectors, the Polonium 210, the dismantling of nuclear installations, wind energy, desalination and nuclear reactors, from non-communication to transparency about nuclear safety, the Jules Horowitz reactor, CO 2 capture and storage, hydrogen, solar energy, the radium, the subcontractors of maintenance of the nuclear fleet, biomass, internal radio-contamination, epidemiological studies, submarine nuclear propulsion, sea energy, the Three Mile Island accident, the Chernobyl accident, the Fukushima accident, the nuclear after Fukushima

  16. Solar Panel Buffeted by Wind at Phoenix Site

    2008-01-01

    Winds were strong enough to cause about a half a centimeter (.19 inch) of motion of a solar panel on NASA's Phoenix Mars lander when the lander's Surface Stereo Imager took this picture on Aug. 31, 2008, during the 96th Martian day since landing. The lander's telltale wind gauge has been indicating wind speeds of about 4 meters per second (9 miles per hour) during late mornings at the site. These conditions were anticipated and the wind is not expected to do any harm to the lander. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  17. Patient deaths blamed on long waits at the Phoenix VA

    Robbins RA

    2014-04-01

    Full Text Available No abstract available. Article truncated at 150 words. This morning the lead article in the Arizona Republic was a report blaming as many as 40 deaths at the Phoenix VA on long waits (1. Yesterday, Rep. Jeff Miller, the chairman of the House Committee on Veterans Affairs, held a hearing titled “A Continued Assessment of Delays in VA Medical Care and Preventable Veteran Deaths.” “It appears as though there could be as many as 40 veterans whose deaths could be related to delays in care,” Miller announced to a stunned audience. The committee has spent months investigating patient-care scandals and allegations at VA facilities in Pittsburgh, Atlanta, Miami and other cities. said that dozens of VA hospital patients in Phoenix may have died while awaiting medical care. He went on to say that staff investigators have evidence that the Phoenix VA Health Care System keeps two sets of records to conceal prolonged waits that patients must endure for ...

  18. Corrosion product layers on magnesium alloys AZ31 and AZ61: Surface chemistry and protective ability

    Feliu, S.; Llorente, I.

    2015-01-01

    Highlights: • Surface chemistry of the corrosion product layers on magnesium alloys. • Influence of the type of alloy on the carbonate surface enrichment. • Relation between surface composition and protection properties. - Abstract: This paper studies the chemical composition of the corrosion product layers formed on magnesium alloys AZ31 and AZ61 following immersion in 0.6 M NaCl, with a view to better understanding their protective action. Relative differences in the chemical nature of the layers were quantified by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDX) and low-angle X-ray diffraction (XRD). Corrosion behavior was investigated by Electrochemical Impedance Spectroscopy (EIS) and hydrogen evolution measurement. An inhibitive effect from the corrosion product layers was observed from EIS, principally in the case of AZ31, as confirmed by hydrogen evolution tests. A link was found between carbonate enrichment observed by XPS in the surface of the corrosion product layer, concomitant with the increase in the protective properties observed by EIS

  19. Corrosion product layers on magnesium alloys AZ31 and AZ61: Surface chemistry and protective ability

    Feliu, S., E-mail: sfeliu@cenim.csic.es; Llorente, I.

    2015-08-30

    Highlights: • Surface chemistry of the corrosion product layers on magnesium alloys. • Influence of the type of alloy on the carbonate surface enrichment. • Relation between surface composition and protection properties. - Abstract: This paper studies the chemical composition of the corrosion product layers formed on magnesium alloys AZ31 and AZ61 following immersion in 0.6 M NaCl, with a view to better understanding their protective action. Relative differences in the chemical nature of the layers were quantified by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDX) and low-angle X-ray diffraction (XRD). Corrosion behavior was investigated by Electrochemical Impedance Spectroscopy (EIS) and hydrogen evolution measurement. An inhibitive effect from the corrosion product layers was observed from EIS, principally in the case of AZ31, as confirmed by hydrogen evolution tests. A link was found between carbonate enrichment observed by XPS in the surface of the corrosion product layer, concomitant with the increase in the protective properties observed by EIS.

  20. Facebook Marketing - Fra A-Z

    Mortensen, Thomas Bøtker

    2009-01-01

    Facebook Marketing – Leverage Social Media to Grow Your Business af Steven Holzner er Facebook Marketing fra A-Z, som kan anbefales til virksomheder, som overvejer at bevæge sig ud i cyber space og afprøve mulighederne for at markedsføre sig dér. Bogen beskriver på hvilke væsentlige punkter...... marketing på Facebook adskiller sig fra traditionel marketing, og gennemgår trin for trin de fundamentale ting, som man skal vide for, at virksomheden kan agere med den tilsigtede effekt i et socialt netværk som Facebook. Og eftersom 34 % af den danske befolkning i dag er hoppet med på Facebook vognen og...... har oprettet en profil på Facebook, er potentialet åbenlyst....

  1. PHOENIX MARS MECA NON-IMAGING EDR V1.0

    National Aeronautics and Space Administration — The Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) experiment on the Mars Phoenix Lander consists of four instrument components plus command...

  2. PHOENIX MARS MECA OPTICAL MICROSCOPE 3 RADIOMETRIC SCI V1.0

    National Aeronautics and Space Administration — The Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) experiment on the Mars Phoenix Lander consists of four instrument components plus command...

  3. PHOENIX MARS MECA OPTICAL MICROSCOPE 2 EDR VERSION 1.0

    National Aeronautics and Space Administration — The Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) experiment on the Mars Phoenix Lander consists of four instrument components plus command...

  4. Photometric Properties of Soils at the Mars Phoenix Landing Site: Preliminary Analysis from CRISM EPF Data

    Cull, S. C.; Arvidson, R. E.; Seelos, F.; Wolff, M. J.

    2010-03-01

    Using data from CRISM's Emission Phase Function observations, we attempt to constrain Phoenix soil scattering properties, including soil grain size, single-scattering albedo, and surface phase function.

  5. Effect of the Strain Rate on the Tensile Properties of the AZ31 Magnesium Alloy

    Jeong, Seunghun; Park, Jiyoun; Choi, Ildong [Korea Maritime University, Busan (Korea, Republic of); Park, Sung Hyuk [Korea Institute of Materials Science, Changwon (Korea, Republic of)

    2013-10-15

    The effect of the strain rate at a range of 10‒4 ⁓ 3 × 10{sup 2}s{sup -}1 on the tensile characteristics of a rolled AZ31 magnesium alloy was studied. The normal tensile specimens were tested using a high rate hydraulic testing machine. Specimens were machined from four sheets with different thicknesses, 1, 1.5, 2 and 3 mm, along three directions, 0°, 45°, and 90° to the rolling direction. The results revealed that all the specimens had a positive strain rate sensitivity of strength, that is, the strength increased with increasing strain rate. This is the same tendency as other automotive steels have. Our results suggest that the AZ31 magnesium alloy has better collision characteristics at high strain rates because of improved strength with an increasing strain rate. Ductility decreased with an increasing strain rate with a strain rate under 1 s{sup -}1, but it increased with an increasing strain rate over 1 s{sup -}1. The mechanical properties of the AZ31 magnesium alloy depend on the different microstructures according to the thickness. Two and 3 mm thickness specimens with a coarse and non-uniform grain structure exhibited worse mechanical properties while the 1.5 mm thickness specimens with a fine and uniform grain structure had better mechanical properties. Specimens machined at 0° and 45° to the rolling direction had higher absorbed energy than that of the 90° specimen. Thus, we demonstrate it is necessary to choose materials with proper thickness and machining direction for use in automotive applications.

  6. Effect of the Strain Rate on the Tensile Properties of the AZ31 Magnesium Alloy

    Jeong, Seunghun; Park, Jiyoun; Choi, Ildong; Park, Sung Hyuk

    2013-01-01

    The effect of the strain rate at a range of 10‒4 ⁓ 3 × 10"2s"-1 on the tensile characteristics of a rolled AZ31 magnesium alloy was studied. The normal tensile specimens were tested using a high rate hydraulic testing machine. Specimens were machined from four sheets with different thicknesses, 1, 1.5, 2 and 3 mm, along three directions, 0°, 45°, and 90° to the rolling direction. The results revealed that all the specimens had a positive strain rate sensitivity of strength, that is, the strength increased with increasing strain rate. This is the same tendency as other automotive steels have. Our results suggest that the AZ31 magnesium alloy has better collision characteristics at high strain rates because of improved strength with an increasing strain rate. Ductility decreased with an increasing strain rate with a strain rate under 1 s"-1, but it increased with an increasing strain rate over 1 s"-1. The mechanical properties of the AZ31 magnesium alloy depend on the different microstructures according to the thickness. Two and 3 mm thickness specimens with a coarse and non-uniform grain structure exhibited worse mechanical properties while the 1.5 mm thickness specimens with a fine and uniform grain structure had better mechanical properties. Specimens machined at 0° and 45° to the rolling direction had higher absorbed energy than that of the 90° specimen. Thus, we demonstrate it is necessary to choose materials with proper thickness and machining direction for use in automotive applications.

  7. A comparative corrosion behavior of Mg, AZ31 and AZ91 alloys in 3.5% NaCl solution

    I.B. Singh

    2015-06-01

    Full Text Available The corrosion behavior of Mg, AZ31 and AZ91 has been evaluated in 3.5% NaCl solution using weight loss, electrochemical polarization and impedance measurements. Corrosion rate derived from the weight losses demonstrated the occurrence of steeply fast corrosion reaction on AZ91 alloy after three hours of immersion, indicating the start of galvanic corrosion. An increase of corrosion rate with immersion time was also observed for AZ31 but with lesser extent than AZ91 alloy. Whereas Mg metals showed a decrease of corrosion rate with immersion time, suggesting the formation of a protective layer on their surfaces. In contrast, the corrosion current density (Icorr derived from the Tafel plots, exhibited their corrosion resistances in order of Mg > AZ91 > AZ31. Electrochemical charge transfer resistance (Rct and double layer capacitance measured by electrochemical impedance spectroscopy (EIS, are well in accordance with the measured Icorr. EIS measurements with time and microstructural examination of the corroded and uncorroded samples are helpful in elucidation of results measured by electrochemical polarization.

  8. Laser assisted self-pierce riveting of AZ31 magnesium alloy strips

    Durandet, Y.; Deam, R.; Beer, A.; Song, W.; Blacket, S.

    2010-01-01

    Laser assisted self-piercing riveting (LSPR) is a new solid state process that enables low ductility materials to be mechanically joined without cracking. A simple but effective thermal analysis of LSPR is presented that enabled both the absorption of the laser radiation and heat transfer between plies to be determined. The approach was applied to experimental data for LSPR joining of AZ31B-H24 magnesium alloy sheets. It is shown that by using this analytical approach, the temperature at the onset of joining could be estimated and related to observations of joint quality. It was found that crack-free joints were produced at strip temperatures above 200 o C at the time of rivet insertion.

  9. Twinning behaviors of a rolled AZ31 magnesium alloy under multidirectional loading

    Hou, Dewen [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Liu, Tianmo, E-mail: tmliu@cqu.edu.cn [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Luo, Longjing [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Lu, Liwei [College of Mechanical and Electrical Engineering, Hunan University of Science and Technology, Xiangtan 411201, Hunan (China); Chen, Huicong; Shi, Dongfeng [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China)

    2017-02-15

    The microstructure and texture evolution of an AZ31 magnesium rolled sheet during quasi-static compression at strain rates of 10{sup −3} s{sup −1} has been investigated by in situ electron backscattered diffraction. The influence of the initial and pre-deformed texture on the predominant deformation mechanisms during compression has been examined. It has been found that extensive grain reorientation due to (10 − 12) tensile twinning appeared when compressed along transverse direction. Tensile twin variants were observed under this loading condition, and different variants will cause an effect to the following deformation. Several twinning modes occurred with continuative loading along rolling direction. - Highlights: •Twinning behaviors were investigated through in situ multidirectional compressive tests. •Deformation behavior was affected by the twin variants. •Four types of twinning behaviors were observed during deformation process.

  10. Investigation on the Effect of Pulsed Energy on Strength of Fillet Lap Laser Welded AZ31B Magnesium Alloys

    Salleh, M. N. M.; Ishak, M.; Aiman, M. H.; Idris, S. R. A.; Romlay, F. R. M.

    2017-09-01

    AZ31B magnesium alloy have been hugely applied in the aerospace, automotive, and electronic industries. However, welding thin sheet AZ31B was challenging due to its properties which is easily to evaporated especially using conventional fusion welding method such as metal inert gas (MIG). Laser could be applied to weld this metal since it produces lower heat input. The application of fiber laser welding has been widely since this type of laser could produce better welding product especially in the automotive sectors. Low power fiber laser was used to weld this non-ferrous metal where pulse wave (PW) mode was used. Double fillet lap joint was applied to weld as thin as 0.6 mm thick of AZ31B and the effect of pulsed energy on the strength was studied. Bond width, throat length, and penetration depth also was studied related to the pulsed energy which effecting the joint. Higher pulsed energy contributes to the higher fracture load with angle of irradiation lower than 3 °

  11. Recommendation Report: EJournals/EBooks A-Z Management System

    Ramli, Rindra M.

    2014-01-01

    This is a recommendation report for KAUST Library on the Ejournals / EBooks AZ Management systems project. It briefly described the issues faced by the ERM Team, project plan overview and the project findings as well as the recommendation(s).

  12. Wood Polymer Composites Technology Supporting the Recovery and Protection of Tropical Forests: The Amazonian Phoenix Project

    Antonio D. Nobre

    2009-12-01

    Full Text Available The Amazon Rain Forest has attracted worldwide attention due its large scale services to climate and also due to the green house gas emissions arising from deforestation. Contributing to the later and detrimental to the former, timber logging in the region has very low efficiency (only 16% in the production chain. Such timber extraction, often referred to as selective logging, has been claimed as a sustainable extractive industry, because the forest is said to restore itself through regenerative growth. But forest regeneration in the Amazon occurs naturally only in a very limited scale, resulting that large scale, low efficiency logging poses a big treat to the functional integrity of the biome, supplying to the market only a fraction of what it could if done differently. So, instead of extracting big centennial logs from the forests, the Amazonian Phoenix project proposes that large expanses of degraded lands be reforested using pioneer plants species from the forest itself. These plants have the capacity to heal gaps in the canopy, being able to grow and produce woody biomass in very extreme conditions. The idea is to mimic the regenerative dynamics of the natural ecosystem in short cycle agrosilvicultural production areas, utilizing a variety of technologies to transform raw fibers from these fast growth native plants into a variety of materials with high aggregated value. This communication presents the research on natural fibers by the Polymeric Composites Group within the Amazonian Phoenix Project. Sustainable technologies employing materials with good and responsible ecological footprints are important and necessary stimulus for a change in the destructive economical activities present in the Amazon frontiers. The relatively well established wood polymer composites technology, for example, is a good candidate solution. Two research and development fields are proposed: the first one considers production systems with simple and cheap

  13. A Statistical Approach for Gain Bandwidth Prediction of Phoenix-Cell Based Reflect arrays

    Hassan Salti

    2018-01-01

    Full Text Available A new statistical approach to predict the gain bandwidth of Phoenix-cell based reflectarrays is proposed. It combines the effects of both main factors that limit the bandwidth of reflectarrays: spatial phase delays and intrinsic bandwidth of radiating cells. As an illustration, the proposed approach is successfully applied to two reflectarrays based on new Phoenix cells.

  14. 241-AZ-101 pump removal trough analysis

    Coverdell, B.L.

    1995-01-01

    As part of the current Hanford mission of environmental cleanup, various long length equipment must be removed from highly radioactive waste tanks. The removal of equipment will utilize portions of the Equipment Removal System for Project W320 (ERS-W320), specifically the 50 ton hydraulic trailer system. Because the ERS-W320 system was designed to accommodate much heavier equipment it is adequate to support the dead weight of the trough, carriage and related equipment for 241AZ101 pump removal project. However, the ERS-W320 components when combined with the trough and its' related components must also be analyzed for overturning due to wind loads. Two troughs were designed, one for the 20 in. diameter carriage and one for the 36 in. diameter carriage. A proposed 52 in. trough was not designed and, therefore is not included in this document. In order to fit in the ERS-W320 strongback the troughs were design with the same widths. Structurally, the only difference between the two troughs is that more material was removed from the stiffener plates on the 36 in trough. The reduction in stiffener plate material reduces the allowable load. Therefore, only the 36 in. trough was analyzed

  15. Neutron radiography at the University of Michigan's Phoenix Memorial Laboratory

    Lindsay, J.T.; Elam, S.; Koblish, T.; Lee, P.; McAuliffe, D.

    1990-01-01

    Real-time neutron radiography (RTNR) is rapidly becoming a valuable tool for nondestructive testing and basic research with a wide variety of applications. The Phoenix Memorial Laboratory (PML) at the University of Michigan has developed an RTNR facility and has been using this facility to study several phenomena of interest to researchers in many areas. These phenomena include imaging of the internal fluid flow in gas turbine engine nozzles and coking and debris deposition in several gas turbine nozzles. This paper presents a summary of the technique and facilities involved in these applications

  16. Phoenix type concepts for transmutation of LWR waste minor actinides

    Segev, M.

    1994-01-01

    A number of variations on the original Phoenix theme were studied. The basic rationale of the Phoenix incinerator is making oxide fuel of the LWR waste minor actinides, loading it in an FFTF-like subcritical core, then bombarding the core with the high current beam accelerated protons to generate considerable energy through spallation and fission reactions. As originally assessed, if the machine is fed with 1600 MeV protons in a 102 mA current, then 8 core modules are driven to transmute the yearly minor actinides waste of 75 1000 MW LWRs into Pu 238 and fission products; in a 2 years cycle the energy extracted is 100000 MW d/T. This performance cannot be substantiated in a rigorous analysis. A calculational consistent methodology, based on a combined execution of the Hermes, NCNP, and Korigen codes, shows, nonetheless that changes in the original Phoenix parameters can upgrade its performance.The original Phoenix contains 26 tons minor actinides in 8 core modules; 1.15 m 3 module is shaped for 40% neutron leakage; with a beam of 102 mA the 8 modules are driven to 100000 MW/T in 10.5 years, burning out the yearly minor actinide waste of 15 LWRs; the operation must be assisted by grid electricity. If the 1.15 m 3 module is shaped to allow only 28% leakage, then a beam of 102 mA will drive the 8 modules to 100000 MW/T in 3.5 years, burning out the yearly minor actinides waste of 45 LWRs. Some net grid electricity will be generated. If 25 tons minor actinides are loaded into 5 modules, each 1.72 m 3 in volume and of 24% leakage, then a 97 mA beam will drive the module to 100000 MW/T in 2.5 years, burning out the yearly minor actinides waste of 70 LWRs. A considerable amount of net grid electricity will be generated. If the lattice is made of metal fuel, and 26 tons minor actinides are loaded into 32 small modules, 0.17 m 3 each, then a 102 mA beam will drive the modules to 100000 MW/T in 2 years, burning out the yearly minor actinides waste of 72 LWRs. A considerable

  17. Caustic leaching of composite AZ-101/AZ-102 Hanford tank sludge

    Rapko, B.M.; Wagner, M.J.

    1997-07-01

    To reduce the quantity (and hence the cost) of glass canisters needed for disposing of high-level radioactive wastes from the Hanford tank farms, pretreatment processes are needed to remove as much nonradioactive material as possible. This report describes the results of a laboratory-scale caustic leaching test performed on a composite derived from a combination of 241-AZ-101 and 241-AZ-102 Hanford Tank sludges. The goals of this FY 1996 test were to evaluate the effectiveness of caustic leaching on removing key components from the sludge and to evaluate the effectiveness of varying the free-hydroxide concentrations by incrementally increasing the free hydroxide concentration of the leach steps up to 3 M free hydroxide. Particle-size analysis of the treated and untreated sludge indicated that the size and range of the sludge particles remained essentially unchanged by the caustic leaching treatment. Both before and after caustic leaching, a particle range of 0.2 microm to 50 microm was observed, with mean particle diameters of 8.5 to 9 microm based on the volume distribution and mean particle diameters of 0.3 to 0.4 microm based on the number distribution

  18. Physics Simulations of fluids - a brief overview of Phoenix FD

    CERN. Geneva; Nikolov, Svetlin

    2014-01-01

    The presentation will briefly describe the simulation and rendering of fluids with Phoenix FD, and then proceed into implementation details. We will present our methods of parallelizing the core simulation algorithms and our utilization of the GPU. We will also show how we take advantage of computational fluid dynamics specifics in order to speed up the preview and final rendering, thus achieving a quick pipeline for the creation of various visual effects. About the speakers Ivaylo Iliev is a Senior Software developer at Chaos Group and is the creator of the Phoenix FD simulator for fluid effects. He has a strong interest in physics and has worked on military simulators before focusing on visual effects. He has a Master?s degree from the Varna Technical University. Svetlin Nikolov is a Senior Software developer at Chaos Group with keen interest in physics and artificial intelligence and 7 years of experience in the software industry. He comes from a game development background with a focu...

  19. Morning Frost in Trench Dug by Phoenix, Sol 113

    2008-01-01

    This image from the Surface Stereo Imager on NASA's Phoenix Mars Lander shows morning frost inside the 'Snow White' trench dug by the lander, in addition to subsurface ice exposed by use of a rasp on the floor of the trench. The camera took this image at about 9 a.m. local solar time during the 113th Martian day of the mission (Sept. 18, 2008). Bright material near and below the four-by-four set of rasp holes in the upper half of the image is water-ice exposed by rasping and scraping in the trench earlier the same morning. Other bright material especially around the edges of the trench, is frost. Earlier in the mission, when the sun stayed above the horizon all night, morning frost was not evident in the trench. This image is presented in approximately true color. The trench is 4 to 5 centimeters (about 2 inches) deep, about 23 centimeters (9 inches) wide. Phoenix landed on a Martian arctic plain on May 25, 2008. The mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.

  20. The Thermal Electrical Conductivity Probe (TECP) for Phoenix

    Zent, Aaron P.; Hecht, Michael H.; Cobos, Doug R.; Campbell, Gaylon S.; Campbell, Colin S.; Cardell, Greg; Foote, Marc C.; Wood, Stephen E.; Mehta, Manish

    2009-01-01

    The Thermal and Electrical Conductivity Probe (TECP) is a component of the Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) payload on the Phoenix Lander. TECP will measure the temperature, thermal conductivity and volumetric heat capacity of the regolith. It will also detect and quantify the population of mobile H2O molecules in the regolith, if any, throughout the polar summer, by measuring the electrical conductivity of the regolith, as well as the dielectric permittivity. In the vapor phase, TECP is capable of measuring the atmospheric H2O vapor abundance, as well as augment the wind velocity measurements from the meteorology instrumentation. TECP is mounted near the end of the 2.3 m Robotic Arm, and can be placed either in the regolith material or held aloft in the atmosphere. This paper describes the development and calibration of the TECP. In addition, substantial characterization of the instrument has been conducted to identify behavioral characteristics that might affect landed surface operations. The greatest potential issue identified in characterization tests is the extraordinary sensitivity of the TECP to placement. Small gaps alter the contact between the TECP and regolith, complicating data interpretation. Testing with the Phoenix Robotic Arm identified mitigation techniques that will be implemented during flight. A flight model of the instrument was also field tested in the Antarctic Dry Valleys during the 2007-2008 International Polar year. 2

  1. Efficacy of Phoenix dactylifera L. (Date Palm Creams on Healthy Skin

    Sidra Meer

    2017-05-01

    Full Text Available The date palm fruit (Phoenix dactylifera L. Arecaceae is used in most of the countries of the world and is an essential part of the diet, especially in many Arabian countries. Phoenix dactylifera L. fruits are a rich source of sugars (glucose and fructose, vitamins (A, C, and B complex, fibers, minerals, and phenolic compounds having antioxidant and anti-inflammatory properties. This study is designed to explore the Phoenix dactylifera L. fruit for skin care. A single-blinded, placebo control trial was conducted, including 11 healthy female volunteers after their informed consent. The efficacy of the Phoenix dactylifera L. extract (4% was evaluated in cream form after one, two, three, four, six, and eight weeks of treatment compared with the baseline. Prior to the study, the composition of the extract was analyzed to understand the underlying mechanisms by which the extract affects skin. Treating facial skin with the Phoenix dactylifera L. extract significantly improved all parameters investigated, such as skin elasticity, pigmentation, redness, brightness, and hydration and led to the improvement of the facial skin. There were no adverse reactions noted during the course of the patch test, demonstrating that the extract could be safe to apply on the skin. The Phoenix dactylifera L. fruit extract serves as a skin care ingredient that significantly improves characteristics important for perception of skin ageing and health. The efficacy of the treatment is possibly due to a combination of numerous active substances found in the Phoenix dactylifera L. extract.

  2. AZ91C magnesium alloy modified by Cd

    Shabadi, R.; Ambat, Rajan; Dwarakadasa, E.S.

    2014-01-01

    In the present work, the effect of Cd on the microstructure, mechanical properties and general corrosion behaviour of AZ91C alloys was investigated. Addition of Cd was found not to be efficient in modifying/refining the microstructure or β-phase. A morphology change in β-phase from fine continuous...... precipitates to discontinuous β-phase upon the addition of Cd was observed. A marginal increment in mechanical properties was observed. General corrosion behaviour was followed with weight loss measurements, potentiostatic polarisation studies and surface studies in 3.5% sodium chloride solution and 3.......5% sodium chloride with 2% potassium dichromate solution. Cd addition deteriorated the corrosion behaviour of AZ91C. This behaviour was attributed to the formation of chunks of β-phase upon the addition of Cd. AZ91C with refined β-phase distribution, performed rather better in the NaCl solutions....

  3. Animated Optical Microscope Zoom in from Phoenix Launch to Martian Surface

    2008-01-01

    [figure removed for brevity, see original site] Click on image for animation This animated camera view zooms in from NASA's Phoenix Mars Lander launch site all the way to Phoenix's Microscopy and Electrochemistry and C Eonductivity Analyzer (MECA) aboard the spacecraft on the Martian surface. The final frame shows the soil sample delivered to MECA as viewed through the Optical Microscope (OM) on Sol 17 (June 11, 2008), or the 17th Martian day. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  4. Results of the Phoenix Relative Humidity Sensor Recalibration

    Martinez, G.; Fischer, E.; Renno, N. O.

    2017-12-01

    We show results of the recalibration of the Thermal and Electrical Conductivity Probe (TECP) relative humidity (RH) sensor of the Phoenix Mars lander [Zent et al., 2009]. Due to uncertainties in its pre-flight calibration, which partially overlapped the environmental conditions found at the Phoenix landing site [Tamppari et al., 2010], only the raw, unprocessed output of the TECP RH sensor is available in NASA's Planetary Data System (PDS). The sensor's calibration was revised in 2016 to correct for inaccuracies at the lowest temperatures [Zent et al., 2016], but the new processed RH values were not posted in the PDS. We have been using a spare engineering unit of the TECP to recalibrate the sensor in the full range of Phoenix landing site conditions in the Michigan Mars Environmental Chamber (MMEC) [Fischer et al., 2016]. We compare raw output data of the engineering unit in the MMEC with that of the flight unit from the preflight calibration. We observed that the engineering unit's RH sensor output was shifted to higher values compared to the flight unit's output at the same conditions of temperature and humidity. Based on this shift, we use a translation function that fits the in-situ measurements of the flight unit into the engineering unit output space. To improve the accuracy of this function, we use additional observations corresponding to saturated conditions when near-surface fog was observed [Whiteway et al., 2009], as well as observations around noon when the RH is expected to be below 5%. The entire range of conditions observed on the Martian surface is covered in our recalibration. The raw output of the sensor is used to obtain a new calibration function. This allows us to obtain high-level RH data at Martian polar conditions. The recalibrated data will be posted in the PDS. REFERENCES: Fischer, E., et al. (2016), Astrobiology, 16, 12, doi: 10.1089/ast.2016.1525. Tamppari, L. K., et al. (2010), J. Geophys. Res., 115, E00E17, doi:10.1029/2009JE003415

  5. Laser-assisted micro sheet forming

    Holtkamp, Jens; Gillner, Arnold

    2008-01-01

    The fast growing market for micro technical products requires parts with increasing complexity. While sheet metal forming enables low cost mass production with short cycle times, it is limited by the maximum degree of deformation and the quality of the cut edge. The technology of warm forming partially eliminates these deficiencies. This operation takes place at elevated temperatures before structural transformation is initiated. It combines characteristic advantages of traditional cold and hot forming processes. Lasers as heat sources provide a high, selective and controllable energy input. The general difficulty of a uniform temperature distribution during the heating process can be reached by using an Axicon which generates an annulus on the sheet metal surface. The temperature of the workpiece, measured by a pyrometer, is tuned by a PI-Controller. A tool incorporating a multistage operation die is used for the manufacturing of up to three parts at the same time. The tool is integrated into a hydraulical press. A gearwheel made of the magnesium alloy AZ31 is chosen as metal demonstrator. The quality of these punched parts could be significantly improved at elevated temperatures

  6. AZ-101 Mixer Pump Test Qualification Test Procedures (QTP)

    THOMAS, W.K.

    2000-01-01

    Describes the Qualification test procedure for the AZ-101 Mixer Pump Data Acquisition System (DAS). The purpose of this Qualification Test Procedure (QTP) is to confirm that the AZ-101 Mixer Pump System has been properly programmed and hardware configured correctly. This QTP will test the software setpoints for the alarms and also check the wiring configuration from the SIMcart to the HMI. An Acceptance Test Procedure (ATP), similar to this QTP will be performed to test field devices and connections from the field

  7. 76 FR 78180 - Proposed Modification of Class E Airspace; Douglas, AZ

    2011-12-16

    ...-1313; Airspace Docket No. 11-AWP-17] Proposed Modification of Class E Airspace; Douglas, AZ AGENCY... action proposes to modify Class E airspace at Bisbee Douglas International Airport, Douglas, AZ... feet above the surface at Douglas, AZ. Additional controlled airspace is necessary to accommodate...

  8. Developing Carbon Budgets for Cities: Phoenix as a Case Study

    McHale, M. R.; Baker, L. A.; Koerner, B. A.; Grimm, N. B.

    2008-12-01

    Studies have shown that cities can alter regional carbon dynamics through changing ecosystem productivity, overall carbon cycling rate, and total carbon storage in vegetation and soils. Furthermore, people in urban regions import a large amount of carbon in food and fuel, as well as release an exceptional amount of CO2 into the atmosphere. Numerous studies have attempted to quantify some sources and sinks of carbon in urban areas, although a complete carbon budget for a city that accounts for total inputs, outputs, and storage within the ecosystem has yet to be fully accomplished. One challenge is associated with attaining the data necessary to accurately account for all carbon dynamics in these heterogeneous and complex ecosystems. Our goal was to estimate a budget for the Phoenix metropolitan area while developing methodology to calculate carbon dynamics in urban systems that can be applied to cities across the US. Only with comparable carbon budgets for multiple cities will we finally begin to understand the influence of urbanization on carbon dynamics. Our analysis shows when calculating certain variables like transportation emissions, results can vary radically (up to 250%) depending on the data source and methodology implemented (i.e. bottom-up vs. top-down). A common assumption is that productivity and carbon storage will increase with urbanization in arid systems due to water and nutrient inputs, as well as changes in vegetation structure; however, our results indicated that this may not actually be the case in Phoenix where a large number of residents design landscapes to conserve water. Even if all urban expansion was dedicated to landscapes designed for carbon sequestration and storage, vegetation and soils will unlikely have a large effect on the C budget without significant changes in transportation and lifestyle choices.

  9. Mechanical characterization and constitutive modeling of Mg alloy sheets

    Mekonen, M. Nebebe; Steglich, D.; Bohlen, J.; Letzig, D.; Mosler, J.

    2012-01-01

    Highlights: ► Material characterization of the Mg alloys AZ31 and ZE10 at elevated temperatures. ► Distortion of the yield locus does not depend on the strain rate. ► Novel constitutive model suitable for the analysis of sheet forming of magnesium. ► Strain-dependent r-values are included within the model. ► The model is thermodynamically consistent and accounts for distortional hardening. - Abstract: In this paper, an experimental mechanical characterization of the magnesium alloys ZE10 and AZ31 is performed and a suitable constitutive model is established. The mechanical characterization is based on uniaxial tensile tests. In order to avoid poor formability at room temperature, the tests were conducted at elevated temperature (200 °C). The uniaxial tensile tests reveal sufficient ductility allowing sheet forming processes at this temperature. The differences in yield stresses and plastic strain ratios (r-values) confirm the anisotropic response of the materials under study. The constitutive model is established so that the characteristic mechanical features observed in magnesium alloys such as anisotropy and compression-tension asymmetry can be accommodated. This model is thermodynamically consistent, incorporates rate effect, is formulated based on finite strain plasticity theory and is applicable in sheet forming simulations of magnesium alloys. More precisely, a model originally proposed by Cazacu and Barlat in 2004 and later modified to account for the evolution of the material anisotropy is rewritten in a thermodynamically consistent framework. The calibrated constitutive model is shown to capture the characteristic mechanical features observed in magnesium alloy sheets.

  10. Effect of fiber laser parameters on laser welded AZ31B Magnesium alloys

    Mat Salleh Naqiuddin

    2017-01-01

    Full Text Available Recently, the usage of Magnesium (Mg alloys has been hugely applied in the industrial application such as in automotive, marine, and electronic due to its advantages of recyclability and lightweight. This alloys required low heat input to be weld since it is easily evaporated due to the Magnesium Oxide (MgO at the surface and it also possesses lower melting point compared to steel. Laser welding is more convenient to weld Mg alloys due to its high power and lower heat input. AZ31B was selected since it has strong mechanical properties among others Mg alloys due to the major alloying elements; Aluminium (Al and Zinc (Zn. Low power fiber laser machine with wavelength of 900 nm was used in this experiment. The intention of this work was to investigate the effect of low power fiber laser parameters and effect of shielding gas on weld penetration and microstructure. Another aim in this work was to produce the joint for this thin sheets metal. Penetration depth and microstructure evaluation were emphasized in the analysis section. Bead-on-Plate (BOP and laser lap welding was conducted on AZ31B with thicknesses of 1.0 mm and 0.6 mm for feasibility study using pulsed wave (PW mode. Defocusing features was used in order to find better focal position, which has less occurrence of evaporation (underfill. The effect of different angle of irradiation was also investigated. Two types of shielding gases, Argon (Ar and Nitrogen (N2 were used in order to study the effect of shielding gas. Lastly, the effect of pulsed energy on penetration types and depth of BOP welded samples was investigated. Focus point was found at focal length of 156 mm with 393.75 μm. For BOP experiment, higher pulsed energy used contributes to melt through defect. Meanwhile, Ns shielding gas proved to be better shielding gas in laser welding the AZ31B. Higher angle of irradiation could reduce the underfill defect. Fillet Lap joint of similar metal was successfully done where 2.0 J of

  11. CRED REA Coral Population Parameters at Howland, Phoenix Islands, Pacific Remote Island Areas in 2008

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 4 sites at Howland, Phoenix...

  12. How Neoliberal Imperialism is Expressed by Programming Strategies of Phoenix TV: A Critical Case Study

    Shuang Xie

    2013-05-01

    Full Text Available This project is a case study of Phoenix Television, which is a Hong Kong-based satellite TV network broadcasting to the global Chinese-speaking community, primarily to the mainland of China. In the theoretical framework of media imperialism and neoliberal imperialism, this study focuses on the programming strategies of Phoenix TV and examines how the global trend of neoliberalism, the Chinese government’s tight control of the media, and the sophisticated ownership of Phoenix TV intertwined to influence on its programming. The analysis of the format, content, naming, and scheduling reveals that US-inspired neoliberalism is expressed in the network’s programming strategies. This expression, in fact, is the balance that Phoenix found between the tension of global and Chinese interests, the tension between revenue making and public service, and the tension between Party-control and profit seeking.

  13. Phoenix light - Heating and cooling with phase-change materials; Phoenix light: Heizen und Kuehlen mit PCM - Schlussbericht

    Haechler, E. [Suiselectra Ingenieurunternehmung AG, Basel (Switzerland); Schneider, B. [Hochschule Esslingen, University of Applied Sciences, Esslingen (Germany)

    2002-12-15

    This final report for the Swiss Federal Office of Energy (SFOE) deals with the use of phase-change materials (PCM) in buildings in order to help provide cooling in summer and heating in winter. General information on PCM and its use in the automotive industry, clothing, heating systems and office materials as well as in the electronics industry is provided. The physical and chemical basics are discussed and examples of PCM use in practice are provided. Also, work done in research institutes is mentioned. PCM systems from various manufacturers are noted. The 'phoenix light' system concept is discussed. The 'comfort cooler' concept is introduced and laboratory measurements made at the University of Applied Sciences in Esslingen, Germany, are discussed. Further, measurements made at an installation in an existing building are presented and discussed. Knowledge gained and the optimisation of the system are discussed. Finally, proposals for further work to be done are noted.

  14. 75 FR 883 - Environmental Impact Statement; Maricopa County, AZ

    2010-01-06

    ...; Maricopa County, AZ AGENCY: Federal Highway Administration (FHWA), DOT. ACTION: Notice of Intent. SUMMARY...: (602) 382-8998, e-mail: [email protected] SUPPLEMENTARY INFORMATION: The FHWA, in cooperation with the... reasonable alternatives will be considered including: (1) Taking no action; (2) using alternate travel modes...

  15. Mixer pump test plan for double shell tank AZ-101

    STAEHR, T.W.

    1999-01-01

    Mixer pump systems have been chosen as the method for retrieval of tank wastes contained in double shell tanks at Hanford. This document describes the plan for testing and demonstrating the ability of two 300 hp mixer pumps to mobilize waste in tank AZ-101. The mixer pumps, equipment and instrumentation to monitor the test were installed by Project W-151

  16. 75 FR 81190 - Television Broadcasting Services; Yuma, AZ

    2010-12-27

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 [DA 10-2365; MB Docket No. 02-151; RM-10453] Television Broadcasting Services; Yuma, AZ AGENCY: Federal Communications Commission. ACTION: Dismissal. SUMMARY: The Commission dismisses the petition for rulemaking filed by Arizona Western College, requesting...

  17. User Manual for the AZ-101 Data Acquisition System (AS-101 DAS)

    BRAYTON, D.D.

    2000-02-17

    User manual for the TK AZ-101 Waste Retrieval System Data Acquisition System. The purpose of this document is to describe use of the AZ-101 Data Acquisition System (AZ-101 DAS). The AZ-101 DAS is provided to fulfill the requirements for data collection and monitoring as defined in Letters of Instruction (LOI) from Numatec Hanford Corporation (NHC) to Fluor Federal Services (FFS). For a complete description of the system, including design, please refer to the AZ-101 DAS System Description document, RPP-5572.

  18. User Manual for the AZ-101 Data Acquisition System (AS-101 DAS)

    BRAYTON, D.D.

    2000-01-01

    User manual for the TK AZ-101 Waste Retrieval System Data Acquisition System. The purpose of this document is to describe use of the AZ-101 Data Acquisition System (AZ-101 DAS). The AZ-101 DAS is provided to fulfill the requirements for data collection and monitoring as defined in Letters of Instruction (LOI) from Numatec Hanford Corporation (NHC) to Fluor Federal Services (FFS). For a complete description of the system, including design, please refer to the AZ-101 DAS System Description document, RPP-5572

  19. Ice sheet in peril

    Hvidberg, Christine Schøtt

    2016-01-01

    Earth's large ice sheets in Greenland and Antarctica are major contributors to sea level change. At present, the Greenland Ice Sheet (see the photo) is losing mass in response to climate warming in Greenland (1), but the present changes also include a long-term response to past climate transitions...

  20. Mobility Balance Sheet 2009

    Jorritsma, P.; Derriks, H.; Francke, J.; Gordijn, H.; Groot, W.; Harms, L.; Van der Loop, H.; Peer, S.; Savelberg, F.; Wouters, P.

    2009-06-01

    The Mobility Balance Sheet provides an overview of the state of the art of mobility in the Netherlands. In addition to describing the development of mobility this report also provides explanations for the growth of passenger and freight transport. Moreover, the Mobility Balance Sheet also focuses on a topical theme: the effects of economic crises on mobility. [nl

  1. Influence of artificial biological fluid composition on the biocorrosion of potential orthopedic Mg-Ca, AZ31, AZ91 alloys

    Gu, X N; Zheng, Y F; Chen, L J

    2009-01-01

    The electrochemical behavior of potential orthopedic Mg-Ca, AZ31 and AZ91 alloys was studied in Hank's solution, Dulbecco's Modified Eagle's Medium (DMEM) and serum-containing medium (DMEM adding 10% fetal bovine serum (DMEM+FBS)) over a 7 day immersion period. The biocorrosion of the above three alloys for various immersion time intervals was investigated by linear polarization and electrochemical impedance spectroscopy (EIS). After 7 day immersion, potentiodynamic polarization tests were carried out and the surface morphologies of experimental samples were examined by scanning electron microscopy (SEM) observation complemented by energy-disperse spectrometer (EDS) analysis. It was shown that the corrosion of magnesium alloys was influenced by the composition of the solution. The results indicated that chloride ion could reduce the corrosion resistance and the hydrocarbonate ions could induce rapid surface passivation. The adsorbed amino acid on the experimental magnesium alloys' surface increased their polarization resistance and reduced current densities. The influence of the serum protein on corrosion was found to be associated with the magnesium alloy compositions. A Mg-Ca alloy exhibited an increased corrosion rate in the presence of serum protein. An AZ31 alloy showed an increased corrosion rate in DMEM+FBS in the initial 3 day immersion and the corrosion rate decreased thereafter. An AZ91 alloy, with high Al content, showed a reduced corrosion rate with the addition of FBS into DMEM.

  2. Influence of artificial biological fluid composition on the biocorrosion of potential orthopedic Mg-Ca, AZ31, AZ91 alloys.

    Gu, X N; Zheng, Y F; Chen, L J

    2009-12-01

    The electrochemical behavior of potential orthopedic Mg-Ca, AZ31 and AZ91 alloys was studied in Hank's solution, Dulbecco's Modified Eagle's Medium (DMEM) and serum-containing medium (DMEM adding 10% fetal bovine serum (DMEM+FBS)) over a 7 day immersion period. The biocorrosion of the above three alloys for various immersion time intervals was investigated by linear polarization and electrochemical impedance spectroscopy (EIS). After 7 day immersion, potentiodynamic polarization tests were carried out and the surface morphologies of experimental samples were examined by scanning electron microscopy (SEM) observation complemented by energy-disperse spectrometer (EDS) analysis. It was shown that the corrosion of magnesium alloys was influenced by the composition of the solution. The results indicated that chloride ion could reduce the corrosion resistance and the hydrocarbonate ions could induce rapid surface passivation. The adsorbed amino acid on the experimental magnesium alloys' surface increased their polarization resistance and reduced current densities. The influence of the serum protein on corrosion was found to be associated with the magnesium alloy compositions. A Mg-Ca alloy exhibited an increased corrosion rate in the presence of serum protein. An AZ31 alloy showed an increased corrosion rate in DMEM+FBS in the initial 3 day immersion and the corrosion rate decreased thereafter. An AZ91 alloy, with high Al content, showed a reduced corrosion rate with the addition of FBS into DMEM.

  3. Influence of artificial biological fluid composition on the biocorrosion of potential orthopedic Mg-Ca, AZ31, AZ91 alloys

    Gu, X N; Zheng, Y F [State Key Laboratory for Turbulence and Complex System and Department of Advanced Materials and Nanotechnology, College of Engineering, Peking University, Beijing 100871 (China); Chen, L J, E-mail: yfzheng@pku.edu.c [School of Material Science and Engineering, Shengyang University of Technology, Shenyang 110023 (China)

    2009-12-15

    The electrochemical behavior of potential orthopedic Mg-Ca, AZ31 and AZ91 alloys was studied in Hank's solution, Dulbecco's Modified Eagle's Medium (DMEM) and serum-containing medium (DMEM adding 10% fetal bovine serum (DMEM+FBS)) over a 7 day immersion period. The biocorrosion of the above three alloys for various immersion time intervals was investigated by linear polarization and electrochemical impedance spectroscopy (EIS). After 7 day immersion, potentiodynamic polarization tests were carried out and the surface morphologies of experimental samples were examined by scanning electron microscopy (SEM) observation complemented by energy-disperse spectrometer (EDS) analysis. It was shown that the corrosion of magnesium alloys was influenced by the composition of the solution. The results indicated that chloride ion could reduce the corrosion resistance and the hydrocarbonate ions could induce rapid surface passivation. The adsorbed amino acid on the experimental magnesium alloys' surface increased their polarization resistance and reduced current densities. The influence of the serum protein on corrosion was found to be associated with the magnesium alloy compositions. A Mg-Ca alloy exhibited an increased corrosion rate in the presence of serum protein. An AZ31 alloy showed an increased corrosion rate in DMEM+FBS in the initial 3 day immersion and the corrosion rate decreased thereafter. An AZ91 alloy, with high Al content, showed a reduced corrosion rate with the addition of FBS into DMEM.

  4. Carbon sheet pumping

    Ohyabu, N.; Sagara, A.; Kawamura, T.; Motojima, O.; Ono, T.

    1993-07-01

    A new hydrogen pumping scheme has been proposed which controls recycling of the particles for significant improvement of the energy confinement in toroidal magnetic fusion devices. In this scheme, a part of the vacuum vessel surface near the divertor is covered with carbon sheets of a large surface area. Before discharge initiation, the sheets are baked up to 700 ∼ 1000degC to remove the previously trapped hydrogen atoms. After being cooled down to below ∼ 200degC, the unsaturated carbon sheets trap high energy charge exchange hydrogen atoms effectively during a discharge and overall pumping efficiency can be as high as ∼ 50 %. (author)

  5. The Phoenix TECP Relative Humidity Sensor: Revised Results

    Zent, Aaron

    2014-01-01

    The original calibration function of the RH sensor on the Phoenix mission's Thermal and Electrical Conductivity Sensor (TECP), has been revised to correct the erroneously-published original calibration equation, to demonstrate the value of this unique data set, and to improve characterization of H2O exchange between the martian regolith and atmosphere. TECP returned two data streams, the temperature of the electronics analog board (Tb) and the digital 12-bit output of the RH sensor (DN), both of which are required to uniquely specify the H2O abundance. Because the original flight instrument calibration was performed against a pair of hygrometers that measured frost point (Tf), the revised calibration equation is also cast in terms of frost point. The choice of functional form for the calibration function is minimally constrained. A series of profiles across the calibration data cloud at constant DN and Tb does not reveal any evidence of a complex functional form. Therefore, a series of polynomials in both DN and Tb was investigated, along with several non-linear functions of DN and Tb.

  6. Knox named Phoenix associate dean of faculty affairs

    Robbins RA

    2016-12-01

    Full Text Available No abstract available. Article truncated after 150 words. The University of Arizona College of Medicine-Phoenix has announced the appointment of nationally recognized physician-scientist Kenneth S. Knox, MD, as the associate dean of faculty affairs. Dr. Knox who has been at the University of Arizona-Tucson since 2008, will oversee the Faculty Affairs Office whose charge is to promote an engaged, diverse community of faculty and scholars that sustain a culture of engagement, professionalism and inclusion. He also will serve as director of research at the Banner Lung Institute. Dr. Knox is a pulmonologist known for his research in sarcoidosis, fungal diagnostics and immunologic lung disease. His work includes developing treatments for HIV, AIDS and valley fever. The division chief of Pulmonary, Allergy, Critical Care and Sleep Medicine in Tucson, Knox was responsible for dramatic growth. His accomplishments include increasing the number of clinical and basic science faculty from five to 30 and fellowship trainings from six to 20, rekindling …

  7. Anther development and microsporogenesis in date palm (phoenix dactylifera l.)

    Jazinizadeh, E.; Majd, A.; Pourpak, Z.

    2017-01-01

    Microsporogenesis and pollen morphology of Phoenix dactylifera L. was studied in this study. Anther, in different developmental stages, was removed, fixed in Formalin-glacial acetic acid-alcohol (FAA), stored in 70% ethanol, embedded in paraffin and then sliced at 8-10mu m by rotary microtome. Staining was carried out with Hematoxylin-Eozin. Scanning electron microscope (SEM) was used to analyze the mature pollen grains. The pollen protein extracts of date palm were obtained from pollen by phosphate buffer saline (PBS). They were separated by 10% SDS-polyacrylamide gel electrophoresis. The anther wall is constituted of five cellular strata: epidermis, monostratified endothecium, middle layer formed by two cellular strata and the secretory tapetum. The microspore mother cells begin meiosis and form tetrads of tetragonal microspores. The mature anther wall consists of an epidermis and an endothecium. Mature pollen grains are two-celled and monosulcate, semitectate -reticulate. SDS- PAGE analysis of mature pollen grains showed protein bands of 10-110 kDa regions. (author)

  8. Propulsive Maneuver Design for the 2007 Mars Phoenix Lander Mission

    Raofi, Behzad; Bhat, Ramachandra S.; Helfrich, Cliff

    2008-01-01

    On May 25, 2008, the Mars Phoenix Lander (PHX) successfully landed in the northern planes of Mars in order to continue and complement NASA's "follow the water" theme as its predecessor Mars missions, such as Mars Odyssey (ODY) and Mars Exploration Rovers, have done in recent years. Instruments on the lander, through a robotic arm able to deliver soil samples to the deck, will perform in-situ and remote-sensing investigations to characterize the chemistry of materials at the local surface, subsurface, and atmosphere. Lander instruments will also identify the potential history of key indicator elements of significance to the biological potential of Mars, including potential organics within any accessible water ice. Precise trajectory control and targeting were necessary in order to achieve the accurate atmospheric entry conditions required for arriving at the desired landing site. The challenge for the trajectory control maneuver design was to meet or exceed these requirements in the presence of spacecraft limitations as well as other mission constraints. This paper describes the strategies used, including the specialized targeting specifically developed for PHX, in order to design and successfully execute the propulsive maneuvers that delivered the spacecraft to its targeted landing site while satisfying the planetary protection requirements in the presence of flight system constraints.

  9. A kinematic hardening constitutive model for the uniaxial cyclic stress-strain response of magnesium sheet alloys at room temperature

    He, Zhitao; Chen, Wufan; Wang, Fenghua; Feng, Miaolin

    2017-11-01

    A kinematic hardening constitutive model is presented, in which a modified form of von Mises yield function is adopted, and the initial asymmetric tension and compression yield stresses of magnesium (Mg) alloys at room temperature (RT) are considered. The hardening behavior was classified into slip, twinning, and untwinning deformation modes, and these were described by two forms of back stress to capture the mechanical response of Mg sheet alloys under cyclic loading tests at RT. Experimental values were obtained for AZ31B-O and AZ31B sheet alloys under both tension-compression-tension (T-C-T) and compression-tension (C-T) loadings to calibrate the parameters of back stresses in the proposed model. The predicted parameters of back stresses in the twinning and untwinning modes were expressed as a cubic polynomial. The predicted curves based on these parameters showed good agreement with the tests.

  10. Characterization of mussel H2A.Z.2: a new H2A.Z variant preferentially expressed in germinal tissues from Mytilus.

    Rivera-Casas, Ciro; González-Romero, Rodrigo; Vizoso-Vazquez, Ángel; Cheema, Manjinder S; Cerdán, M Esperanza; Méndez, Josefina; Ausió, Juan; Eirin-Lopez, Jose M

    2016-10-01

    Histones are the fundamental constituents of the eukaryotic chromatin, facilitating the physical organization of DNA in chromosomes and participating in the regulation of its metabolism. The H2A family displays the largest number of variants among core histones, including the renowned H2A.X, macroH2A, H2A.B (Bbd), and H2A.Z. This latter variant is especially interesting because of its regulatory role and its differentiation into 2 functionally divergent variants (H2A.Z.1 and H2A.Z.2), further specializing the structure and function of vertebrate chromatin. In the present work we describe, for the first time, the presence of a second H2A.Z variant (H2A.Z.2) in the genome of a non-vertebrate animal, the mussel Mytilus. The molecular and evolutionary characterization of mussel H2A.Z.1 and H2A.Z.2 histones is consistent with their functional specialization, supported on sequence divergence at promoter and coding regions as well as on varying gene expression patterns. More precisely, the expression of H2A.Z.2 transcripts in gonadal tissue and its potential upregulation in response to genotoxic stress might be mirroring the specialization of this variant in DNA repair. Overall, the findings presented in this work complement recent reports describing the widespread presence of other histone variants across eukaryotes, supporting an ancestral origin and conserved role for histone variants in chromatin.

  11. Test Excavations at Painted Rock Reservoir: Sites AZ Z:1:7, AZ Z:1:8, and AZ S:16:36.

    1981-11-01

    were dehydrated, trimmed to 12-mm squares, and 77 78 placed in catalyzed (0.05-percent benzoyl peroxide), deinhibited acrylic monomer (50-percent methyl ...refrigeration for 72 hours in partially polymerized ethyl- methyl methacrylate. The methacrylate was polymerized at 50 degrees C and 50 p.s.i. nitrogen...pollen types from fill of Feature 10, AZ Z:l:8 Pollen Type Percent Pinus spp. 0.5 Cheno-Am 92.0 Gramineae 2.0 Ambrosia spp. 0.5 Malvaceae 0.5 Zea spp. 2.0

  12. Anesthesia Fact Sheet

    ... Education About NIGMS NIGMS Home > Science Education > Anesthesia Anesthesia Tagline (Optional) Middle/Main Content Area En español ... Version (464 KB) Other Fact Sheets What is anesthesia? Anesthesia is a medical treatment that prevents patients ...

  13. Structural Biology Fact Sheet

    ... NIGMS NIGMS Home > Science Education > Structural Biology Structural Biology Tagline (Optional) Middle/Main Content Area PDF Version (688 KB) Other Fact Sheets What is structural biology? Structural biology is the study of how biological ...

  14. Radiation protecting sheet

    Makiguchi, Hiroshi.

    1989-01-01

    As protection sheets used in radioactivity administration areas, a thermoplastic polyurethane composition sheet with a thickness of less 0.5 mm, solid content (ash) of less than 5% and a shore D hardness of less than 60 is used. A composite sheet with thickness of less than 0.5 mm laminated or coated with such a thermoplastic polyurethane composition as a surface layer and the thermoplastic polyurethane composition sheet applied with secondary fabrication are used. This can satisfy all of the required properties, such as draping property, abrasion resistance, high breaking strength, necking resistance, endurance strength, as well as chemical resistance and easy burnability in burning furnace. Further, by forming uneveness on the surface by means of embossing, etc. safety problems such as slippage during operation and walking can be overcome. (T.M.)

  15. Global ice sheet modeling

    Hughes, T.J.; Fastook, J.L.

    1994-05-01

    The University of Maine conducted this study for Pacific Northwest Laboratory (PNL) as part of a global climate modeling task for site characterization of the potential nuclear waste respository site at Yucca Mountain, NV. The purpose of the study was to develop a global ice sheet dynamics model that will forecast the three-dimensional configuration of global ice sheets for specific climate change scenarios. The objective of the third (final) year of the work was to produce ice sheet data for glaciation scenarios covering the next 100,000 years. This was accomplished using both the map-plane and flowband solutions of our time-dependent, finite-element gridpoint model. The theory and equations used to develop the ice sheet models are presented. Three future scenarios were simulated by the model and results are discussed

  16. Arizona Libraries: Books to Bytes. Contributed Papers Presented at the AzLA Annual Conference (Phoenix, Arizona, November 17-18, 1995).

    Hammond, Carol, Ed.

    This document contains three papers presented at the 1995 Arizona Library Association conference. Papers include: (1) "ERLs and URLs: ASU Libraries Database Delivery Through Web Technology" (Dennis Brunning & Philip Konomos), which illustrates how and why the libraries at Arizona State University developed a world wide web server and…

  17. The Corrosion Protection of Magnesium Alloy AZ31B

    Danford, M. D.; Mendrek, M. J.; Mitchell, M. L.; Torres, P. D.

    1997-01-01

    Corrosion rates for bare and coated Magnesium alloy AZ31B have been measured. Two coatings, Dow-23(Trademark) and Tagnite(Trademark), have been tested by electrochemical methods and their effectiveness determined. Electrochemical methods employed were the scanning reference electrode technique (SRET), the polarization resistance technique (PR) and the electrochemical impedance spectroscopy technique (EIS). In addition, general corrosion and stress corrosion methods were employed to examine the effectiveness of the above coatings in 90 percent humidity. Results from these studies are presented.

  18. Energy information sheets

    NONE

    1995-07-01

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

  19. High-Speed Rolling of AZ31 Magnesium Alloy Having Different Initial Textures

    Onuki, Yusuke; Hara, Kenichiro; Utsunomiya, Hiroshi; Szpunar, Jerzy A.

    2015-02-01

    It is known that magnesium alloys can be rolled up to a large thickness reduction and develop a unique texture when the rolling speed is high (>1000 m/min). In order to understand the texture formation mechanism during high-strain-rate deformation, high-speed rolling of AZ31 magnesium alloy samples having different initial textures was conducted. The main components of the textures after the rolling were the RD-split basal, which consisted of 10°-20° inclining basal poles from the normal direction toward the rolling direction of the sheet, regardless of the different initial textures. With preheating at 473 K, all the samples were rolled without cracking while all were cracked when preheating was not applied. The optical micrographs and EBSD measurements showed a significant amount of twins and the cracks that developed along the shear bands consisted with laminated twins. Based on the texture simulation using the visco-plastic self-consistent model, it is concluded that the rapid development of the RD-split basal component from the initial basal alignment along the transverse direction was attributable to the tension twinning, The effect of the initial texture on the crack formation can be explained by the activation of the twinning system.

  20. Development of liquid-nitrogen-cooling friction stir spot welding for AZ31 magnesium alloy joints

    Wu, Dong; Shen, Jun; Zhou, Meng-bing; Cheng, Liang; Sang, Jia-xing

    2017-10-01

    A liquid-nitrogen-cooling friction stir spot welding (C-FSSW) technology was developed for welding AZ31 magnesium alloy sheets. The liquid-nitrogen cooling degraded the deformability of the welded materials such that the width of interfacial cracks increased with increasing cooling time. The grain size of the stirred zone (SZ) and the heat-affected zone (HAZ) of the C-FSSW-welded joints decreased, whereas that of the thermomechanically affected zone (TMAZ) increased with increasing cooling time. The maximum tensile shear load of the C-FSSW-welded joints welded with a cooling time of 5 or 7 s was larger than that of the friction stir spot welding (FSSW)-welded joint, and the tensile shear load decreased with increasing cooling time. The microhardness of the C-FSSW-welded joints was greater than that of the FSSW-welded joint. Moreover, the microhardness of the SZ and the HAZ of the C-FSSW-welded joints increased, whereas that of the TMAZ decreased, with increasing cooling time.

  1. 77 FR 74457 - Foreign-Trade Zone 75-Phoenix, Arizona Application for Expansion (New Magnet Site) Under...

    2012-12-14

    ..., Arizona Application for Expansion (New Magnet Site) Under Alternative Site Framework An application has...) adopted by the Board (15 CFR 400.2(c)) to include a new magnet site in Phoenix, Arizona. The application... zone project includes the following magnet sites: Site 1 (338 acres)--within the 550-acre Phoenix Sky...

  2. Enhancing Microstructure and Mechanical Properties of AZ31-MWCNT Nanocomposites through Mechanical Alloying

    J. Jayakumar

    2013-01-01

    Full Text Available Multiwall carbon nanotubes (MWCNTs reinforced Mg alloy AZ31 nanocomposites were fabricated by mechanical alloying and powder metallurgy technique. The reinforcement material MWCNTs were blended in three weight fractions (0.33%, 0.66%, and 1% with the matrix material AZ31 (Al-3%, zinc-1% rest Mg and blended through mechanical alloying using a high energy planetary ball mill. Specimens of monolithic AZ31 and AZ31-MWCNT composites were fabricated through powder metallurgy technique. The microstructure, density, hardness, porosity, ductility, and tensile properties of monolithic AZ31 and AZ31-MWCNT nano composites were characterized and compared. The characterization reveals significant reduction in CNT (carbon nanoTube agglomeration and enhancement in microstructure and mechanical properties due to mechanical alloying through ball milling.

  3. Reorganization of Damaged Chromatin by the Exchange of Histone Variant H2A.Z-2

    Nishibuchi, Ikuno [Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima (Japan); Department of Radiation Oncology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Department of Radiation Oncology, Hiroshima Prefectural Hospital, Hiroshima (Japan); Suzuki, Hidekazu; Kinomura, Aiko; Sun, Jiying; Liu, Ning-Ang [Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima (Japan); Horikoshi, Yasunori [Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima (Japan); Research Center for Mathematics of Chromatin Live Dynamics, Hiroshima University, Hiroshima (Japan); Shima, Hiroki [Department of Biochemistry, Graduate School of Medical Sciences, Tohoku University, Sendai (Japan); Kusakabe, Masayuki; Harata, Masahiko [Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University, Sendai (Japan); Fukagawa, Tatsuo [Department of Molecular Genetics, National Institute of Genetics and The Graduate University for Advanced Studies, Mishima (Japan); Ikura, Tsuyoshi [Laboratory of Chromatin Regulatory Network, Department of Mutagenesis, Radiation Biology Center, Kyoto University, Kyoto (Japan); Ishida, Takafumi [Department of Cardiovascular Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Nagata, Yasushi [Department of Radiation Oncology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Tashiro, Satoshi, E-mail: ktashiro@hiroshima-u.ac.jp [Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima (Japan); Research Center for Mathematics of Chromatin Live Dynamics, Hiroshima University, Hiroshima (Japan)

    2014-07-15

    Purpose: The reorganization of damaged chromatin plays an important role in the regulation of the DNA damage response. A recent study revealed the presence of 2 vertebrate H2A.Z isoforms, H2A.Z-1 and H2A.Z-2. However, the roles of the vertebrate H2A.Z isoforms are still unclear. Thus, in this study we examined the roles of the vertebrate H2A.Z isoforms in chromatin reorganization after the induction of DNA double-strand breaks (DSBs). Methods and Materials: To examine the dynamics of H2A.Z isoforms at damaged sites, we constructed GM0637 cells stably expressing each of the green fluorescent protein (GFP)-labeled H2A.Z isoforms, and performed fluorescence recovery after photobleaching (FRAP) analysis and inverted FRAP analysis in combination with microirradiation. Immunofluorescence staining using an anti-RAD51 antibody was performed to study the kinetics of RAD51 foci formation after 2-Gy irradiation of wild-type (WT), H2A.Z-1- and H2A.Z-2-deficient DT40 cells. Colony-forming assays were also performed to compare the survival rates of WT, H2A.Z-1-, and H2A.Z-2-deficient DT40 cells with control, and H2A.Z-1- and H2A.Z-2-depleted U2OS cells after irradiation. Results: FRAP analysis revealed that H2A.Z-2 was incorporated into damaged chromatin just after the induction of DSBs, whereas H2A.Z-1 remained essentially unchanged. Inverted FRAP analysis showed that H2A.Z-2 was released from damaged chromatin. These findings indicated that H2A.Z-2 was exchanged at DSB sites immediately after the induction of DSBs. RAD51 focus formation after ionizing irradiation was disturbed in H2A.Z-2-deficient DT40 cells but not in H2A.Z-1-deficient cells. The survival rate of H2A.Z-2-deficient cells after irradiation was lower than those of WT and H2A.Z-1- DT40 cells. Similar to DT40 cells, H2A.Z-2-depleted U2OS cells were also radiation-sensitive compared to control and H2A.Z-1-depleted cells. Conclusions: We found that vertebrate H2A.Z-2 is involved in the regulation of the DNA

  4. Reorganization of Damaged Chromatin by the Exchange of Histone Variant H2A.Z-2

    Nishibuchi, Ikuno; Suzuki, Hidekazu; Kinomura, Aiko; Sun, Jiying; Liu, Ning-Ang; Horikoshi, Yasunori; Shima, Hiroki; Kusakabe, Masayuki; Harata, Masahiko; Fukagawa, Tatsuo; Ikura, Tsuyoshi; Ishida, Takafumi; Nagata, Yasushi; Tashiro, Satoshi

    2014-01-01

    Purpose: The reorganization of damaged chromatin plays an important role in the regulation of the DNA damage response. A recent study revealed the presence of 2 vertebrate H2A.Z isoforms, H2A.Z-1 and H2A.Z-2. However, the roles of the vertebrate H2A.Z isoforms are still unclear. Thus, in this study we examined the roles of the vertebrate H2A.Z isoforms in chromatin reorganization after the induction of DNA double-strand breaks (DSBs). Methods and Materials: To examine the dynamics of H2A.Z isoforms at damaged sites, we constructed GM0637 cells stably expressing each of the green fluorescent protein (GFP)-labeled H2A.Z isoforms, and performed fluorescence recovery after photobleaching (FRAP) analysis and inverted FRAP analysis in combination with microirradiation. Immunofluorescence staining using an anti-RAD51 antibody was performed to study the kinetics of RAD51 foci formation after 2-Gy irradiation of wild-type (WT), H2A.Z-1- and H2A.Z-2-deficient DT40 cells. Colony-forming assays were also performed to compare the survival rates of WT, H2A.Z-1-, and H2A.Z-2-deficient DT40 cells with control, and H2A.Z-1- and H2A.Z-2-depleted U2OS cells after irradiation. Results: FRAP analysis revealed that H2A.Z-2 was incorporated into damaged chromatin just after the induction of DSBs, whereas H2A.Z-1 remained essentially unchanged. Inverted FRAP analysis showed that H2A.Z-2 was released from damaged chromatin. These findings indicated that H2A.Z-2 was exchanged at DSB sites immediately after the induction of DSBs. RAD51 focus formation after ionizing irradiation was disturbed in H2A.Z-2-deficient DT40 cells but not in H2A.Z-1-deficient cells. The survival rate of H2A.Z-2-deficient cells after irradiation was lower than those of WT and H2A.Z-1- DT40 cells. Similar to DT40 cells, H2A.Z-2-depleted U2OS cells were also radiation-sensitive compared to control and H2A.Z-1-depleted cells. Conclusions: We found that vertebrate H2A.Z-2 is involved in the regulation of the DNA

  5. Update of PHOENIX-P 42 group library from CENDL-2

    Zhang Baocheng

    1998-01-01

    PHOENIX-P is a lattice physics code system, developed by the Westinghouse Electric Corporation (WEC), which was transplanted and used at Dayabay Nuclear Power Plant (DNPJVC). The associated multi-group (42-group) library was derived from the evaluated nuclear data of ENDF/B-5. Since the original library is from the old evaluated nuclear data, it can not meet all the requirements of reactor physics calculations of the nuclear power plant. So it is necessary to update the library with the latest version of evaluated nuclear data. To do so, based on the investigation of the old library and the information about the library, some programs were developed at China Nuclear Data Center (CNDC) to produce PHOENIX-P format data sets mainly from CENDL-2 and the new data were used to supersede the old ones of the PHOENIX-P library

  6. ALPHA/PHOENIX-P/ANC system validation for Angra-1 neutronic calculations

    Ponzoni Filho, Pedro; Sato, Sadakatu; Santos, Teresinha Ipojuca Cardoso; Fernandes, Vanderlei Borba; Fetterman, R.J.

    1995-01-01

    The ALPHA/PHOENIX-P/ANC (APA) code package is an advanced neutronic calculation system for pressurized water reactor (PWR). PHOENIX-P generates the required cross sections for the fuel, burnable absorbers, control rods and baffle/reflector region. The ALPHA code is used to automate the generation of these cross-sections as well as process the PHOENIX-P results to generate the ANC model input. ANC is a three dimensional advanced nodal code used for the modeling of the, depletion of the fuel in the core, and for the calculation of power distributions, rod worths and other reactivity parameters. This paper provides brief overview of the APA methodology for reload core design of Angra Unit 1 Cycles 1 and 2. Results included are predicted power distributions, control rod worths and other reactivity parameters compared to plant measurements. These results demonstrate that the APA system can be used for the reload core design. (author). 7 refs, 9 figs

  7. First plasma of the A-PHOENIX electron cyclotron resonance ion source

    Thuillier, T.; Lamy, T.; Latrasse, L.; Angot, J.

    2008-01-01

    A-PHOENIX is a new compact hybrid electron cyclotron resonance ion source using a large permanent magnet hexapole (1.92 T at the magnet surface) and high temperature superconducting Solenoids (3 T) to make min-vertical bar B vertical bar structure suitable for 28 GHz cw operation. The final assembly of the source was achieved at the end of June 2007. The first plasma of A-PHOENIX at 18 GHz was done on the 16th of August, 2007. The technological specificities of A-PHOENIX are presented. The large hexapole built is presented and experimental magnetic measurements show that it is nominal with respect to simulation. A fake plasma chamber prototype including thin iron inserts showed that the predicted radial magnetic confinement can be fulfilled up to 2.15 T at the plasma chamber wall. Scheduled planning of experiments until the end of 2008 is presented

  8. ALPHA/PHOENIX-P/ANC system validation for Angra-1 neutronic calculations

    Ponzoni Filho, Pedro; Sato, Sadakatu; Santos, Teresinha Ipojuca Cardoso; Fernandes, Vanderlei Borba [FURNAS, Rio de Janeiro, RJ (Brazil); Fetterman, R.J. [Westinghouse Electric Corp., Pittsburgh, PA (United States)

    1995-12-31

    The ALPHA/PHOENIX-P/ANC (APA) code package is an advanced neutronic calculation system for pressurized water reactor (PWR). PHOENIX-P generates the required cross sections for the fuel, burnable absorbers, control rods and baffle/reflector region. The ALPHA code is used to automate the generation of these cross-sections as well as process the PHOENIX-P results to generate the ANC model input. ANC is a three dimensional advanced nodal code used for the modeling of the, depletion of the fuel in the core, and for the calculation of power distributions, rod worths and other reactivity parameters. This paper provides brief overview of the APA methodology for reload core design of Angra Unit 1 Cycles 1 and 2. Results included are predicted power distributions, control rod worths and other reactivity parameters compared to plant measurements. These results demonstrate that the APA system can be used for the reload core design. (author). 7 refs, 9 figs.

  9. Establishment, management, and maintenance of the phoenix islands protected area.

    Rotjan, Randi; Jamieson, Regen; Carr, Ben; Kaufman, Les; Mangubhai, Sangeeta; Obura, David; Pierce, Ray; Rimon, Betarim; Ris, Bud; Sandin, Stuart; Shelley, Peter; Sumaila, U Rashid; Taei, Sue; Tausig, Heather; Teroroko, Tukabu; Thorrold, Simon; Wikgren, Brooke; Toatu, Teuea; Stone, Greg

    2014-01-01

    The Republic of Kiribati's Phoenix Islands Protected Area (PIPA), located in the equatorial central Pacific, is the largest and deepest UNESCO World Heritage site on earth. Created in 2008, it was the first Marine Protected Area (MPA) of its kind (at the time of inception, the largest in the world) and includes eight low-lying islands, shallow coral reefs, submerged shallow and deep seamounts and extensive open-ocean and ocean floor habitat. Due to their isolation, the shallow reef habitats have been protected de facto from severe exploitation, though the surrounding waters have been continually fished for large pelagics and whales over many decades. PIPA was created under a partnership between the Government of Kiribati and the international non-governmental organizations-Conservation International and the New England Aquarium. PIPA has a unique conservation strategy as the first marine MPA to use a conservation contract mechanism with a corresponding Conservation Trust established to be both a sustainable financing mechanism and a check-and-balance to the oversight and maintenance of the MPA. As PIPA moves forward with its management objectives, it is well positioned to be a global model for large MPA design and implementation in similar contexts. The islands and shallow reefs have already shown benefits from protection, though the pending full closure of PIPA (and assessments thereof) will be critical for determining success of the MPA as a refuge for open-ocean pelagic and deep-sea marine life. As global ocean resources are continually being extracted to support a growing global population, PIPA's closure is both timely and of global significance.

  10. Pyrolysis Characteristics and Kinetics of Phoenix Tree Residues as a Potential Energy

    H. Li

    2015-09-01

    Full Text Available By using a thermogravimetric analyser under argon atmosphere, the pyrolysis process and the kinetic model of phoenix tree residues (the little stem, middle stem, and leaf at a 30 °C min−1 heating rate and the phoenix tree mix at three different heating rates (10 °C min−1, 30 °C min−1, and 50 °C min−1 were examined. The catalyst and the co-pyrolysis samples were at a 30 °C min−1 heating rate. The catalysts were Na2CO3, ZnCl2 and CaO in a mass fraction of 5 %. The experimental results revealed that the phoenix tree residues pyrolysis process consisted of three stages: dehydration stage, main pyrolysis stage, and the slow decomposition of residues. As the heating rate increased, the pyrolysis characteristic temperature of the phoenix tree grew, there was a backward-shift of the pyrolysis rate curve, and the mass loss rate gradually increased. The phoenix tree residues’ activation energy changed throughout the whole pyrolysis process, and the pyrolysis temperature ranges of the three main components (cellulose, hemicellulose, and lignin existed in overlapping phenomenon. As compared to the little stem, middle stem, and leaf, the phoenix tree mix was more likely to be pyrolysed under the same heating rate. Different catalysts had a different impact on the pyrolysis: ZnCl2 moved the start point of the reaction to the lower temperatures, but did not speed up the reaction; Na2CO3 speeded up the reaction without changing the start point of the reaction; CaO speeded up the reaction, moved the start point of the reaction to higher temperatures.

  11. Rhizosphere effects of PAH-contaminated soil phytoremediation using a special plant named Fire Phoenix.

    Liu, Rui; Xiao, Nan; Wei, Shuhe; Zhao, Lixing; An, Jing

    2014-03-01

    The rhizosphere effect of a special phytoremediating species known as Fire Phoenix on the degradation of polycyclic aromatic hydrocarbons (PAHs) was investigated, including changes of the enzymatic activity and microbial communities in rhizosphere soil. The study showed that the degradation rate of Σ8PAHs by Fire Phoenix was up to 99.40% after a 150-day culture. The activity of dehydrogenase (DHO), peroxidase (POD) and catalase (CAT) increased greatly, especially after a 60-day culture, followed by a gradual reduction with an increase in the planting time. The activity of these enzymes was strongly correlated to the higher degradation performance of Fire Phoenix growing in PAH-contaminated soils, although it was also affected by the basic characteristics of the plant species itself, such as the excessive, fibrous root systems, strong disease resistance, drought resistance, heat resistance, and resistance to barren soil. The activity of polyphenoloxidase (PPO) decreased during the whole growing period in this study, and the degradation rate of Σ8PAHs in the rhizosphere soil after having planted Fire Phoenix plants had a significant (R(2)=0.947) negative correlation with the change in the activity of PPO. Using an analysis of the microbial communities, the results indicated that the structure of microorganisms in the rhizosphere soil could be changed by planting Fire Phoenix plants, namely, there was an increase in microbial diversity compared with the unplanted soil. In addition, the primary advantage of Fire Phoenix was to promote the growth of flora genus Gordonia sp. as the major bacteria that can effectively degrade PAHs. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  12. Tank 241-AZ-102 Privatization Push Mode Core Sampling and Analysis Plan

    TEMPLETON, A.M.

    1999-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for samples obtained from tank 241-AZ-102

  13. Tank 241-AZ-102 Privatization Push Mode Core Sampling and Analysis Plan

    RASMUSSEN, J.H.

    2000-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for samples obtained from tank 241-AZ-102

  14. 241-AZ Tank Farm Construction Extent of Condition Review for Tank Integrity

    Barnes, Travis J.; Boomer, Kayle D.; Gunter, Jason R.; Venetz, Theodore J.

    2013-07-30

    This report provides the results of an extent of condition construction history review for tanks 241-AZ-101 and 241-AZ-102. The construction history of the 241-AZ tank farm has been reviewed to identify issues similar to those experienced during tank AY-102 construction. Those issues and others impacting integrity are discussed based on information found in available construction records, using tank AY-102 as the comparison benchmark. In the 241-AZ tank farm, the second DST farm constructed, both refractory quality and tank and liner fabrication were improved.

  15. Microstructural Characteristics and Mechanical Properties of 2205/AZ31B Laminates Fabricated by Explosive Welding

    Yan Li

    2017-04-01

    Full Text Available A bimetal composite of 2205 duplex stainless steel and AZ31B magnesium alloy was cladded successfully through the method of explosive welding. The microstructural characteristics and mechanical properties of 2205/AZ31B bimetal composite are discussed. The interface of 2205/AZ31B bimetallic composite was a less regular wavy morphology with locally melted pockets. Adiabatic shear bands occurred only in the AZ31B side near explosive welding interface. The microstructure observed with EBSD showed a strong refinement near the interface zones. Line scan confirmed that the interface had a short element diffusion zone which would contribute to the metallurgical bonding between 2205 duplex stainless steel and AZ31B magnesium alloy. The value of micro-hardness near the bonding interface of composite plate increased because of work hardening and grain refinement. The tensile shear strength of bonding interface of 2205/AZ31B composite was 105.63 MPa. Tensile strength of 2205/AZ31B composite material was higher than the base AZ31B. There were two abrupt drops in stress in the stress–strain curves of the 2205/AZ31B composite materials.

  16. The chloroplast DNA locus psbZ-trnfM as a potential barcode marker in Phoenix L. (Arecaceae

    Marco Ballardini

    2013-12-01

    Full Text Available The genus Phoenix (Arecaceae comprises 14 species distributed from Cape Verde Islands to SE Asia. It includes the economically important species Phoenix dactylifera. The paucity of differential morphological and anatomical useful characters, and interspecific hybridization, make identification of Phoenix species difficult. In this context, the development of reliable DNA markers for species and hybrid identification would be of great utility. Previous studies identified a 12 bp polymorphic chloroplast minisatellite in the trnG(GCC-trnfM(CAU spacer, and showed its potential for species identification in Phoenix. In this work, in order to develop an efficient DNA barcode marker for Phoenix, a longer cpDNA region (700 bp comprising the mentioned minisatellite, and located between the psbZ and trnfM(CAU genes, was sequenced. One hundred and thirty-six individuals, representing all Phoenix species except P. andamanensis, were analysed. The minisatellite showed 2-7 repetitions of the 12 bp motif, with 1-3 out of seven haplotypes per species. Phoenix reclinata and P. canariensis had species-specific haplotypes. Additional polymorphisms were found in the flanking regions of the minisatellite, including substitutions, indels and homopolymers. All this information allowed us to identify unambiguously eight out of the 13 species, and overall 80% of the individuals sampled. Phoenix rupicola and P. theophrasti had the same haplotype, and so had P. atlantica, P. dactylifera, and P. sylvestris (the “date palm complex” sensu Pintaud et al. 2013. For these species, additional molecular markers will be required for their unambiguous identification. The psbZ-trnfM(CAU region therefore could be considered as a good basis for the establishment of a DNA barcoding system in Phoenix, and is potentially useful for the identification of the female parent in Phoenix hybrids.

  17. Disintegration of liquid sheets

    Mansour, Adel; Chigier, Norman

    1990-01-01

    The development, stability, and disintegration of liquid sheets issuing from a two-dimensional air-assisted nozzle is studied. Detailed measurements of mean drop size and velocity are made using a phase Doppler particle analyzer. Without air flow the liquid sheet converges toward the axis as a result of surface tension forces. With airflow a quasi-two-dimensional expanding spray is formed. The air flow causes small variations in sheet thickness to develop into major disturbances with the result that disruption starts before the formation of the main break-up region. In the two-dimensional variable geometry air-blast atomizer, it is shown that the air flow is responsible for the formation of large, ordered, and small chaotic 'cell' structures.

  18. Safety advice sheets

    HSE Unit

    2013-01-01

    You never know when you might be faced with questions such as: when/how should I dispose of a gas canister? Where can I find an inspection report? How should I handle/store/dispose of a chemical substance…?   The SI section of the DGS/SEE Group is primarily responsible for safety inspections, evaluating the safety conditions of equipment items, premises and facilities. On top of this core task, it also regularly issues “Safety Advice Sheets” on various topics, designed to be of assistance to users but also to recall and reinforce safety rules and procedures. These clear and concise sheets, complete with illustrations, are easy to display in the appropriate areas. The following safety advice sheets have been issued so far: Other sheets will be published shortly. Suggestions are welcome and should be sent to the SI section of the DGS/SEE Group. Please send enquiries to general-safety-visits.service@cern.ch.

  19. Ice Sheets & Ice Cores

    Mikkelsen, Troels Bøgeholm

    Since the discovery of the Ice Ages it has been evident that Earth’s climate is liable to undergo dramatic changes. The previous climatic period known as the Last Glacial saw large oscillations in the extent of ice sheets covering the Northern hemisphere. Understanding these oscillations known....... The first part concerns time series analysis of ice core data obtained from the Greenland Ice Sheet. We analyze parts of the time series where DO-events occur using the so-called transfer operator and compare the results with time series from a simple model capable of switching by either undergoing...

  20. Energy information sheets

    1993-12-02

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the general public. Written for the general public, the EIA publication Energy Information Sheets was developed to provide information on various aspects of fuel production, prices, consumption and capability. The information contained herein pertains to energy data as of December 1991. Additional information on related subject matter can be found in other EIA publications as referenced at the end of each sheet.

  1. (Ca,Mg)-Carbonate and Mg-Carbonate at the Phoenix Landing Site: Evaluation of the Phoenix Lander's Thermal Evolved Gas Analyzer (TEGA) Data Using Laboratory Simulations

    Sutter, B.; Ming, D. W.; Boynton, W. V.; Niles, P. B.; Morris, R. V.

    2011-01-01

    Calcium carbonate (4.5 wt. %) was detected in the soil at the Phoenix Landing site by the Phoenix Lander s The Thermal and Evolved Gas Analyzer [1]. TEGA operated at 12 mbar pressure, yet the detection of calcium carbonate is based on interpretations derived from thermal analysis literature of carbonates measured under ambient (1000 mbar) and vacuum (10(exp -3) mbar) conditions [2,3] as well as at 100 and 30 mbar [4,5] and one analysis at 12 mbar by the TEGA engineering qualification model (TEGA-EQM). Thermodynamics (Te = H/ S) dictate that pressure affects entropy ( S) which causes the temperature (Te) of mineral decomposition at one pressure to differ from Te obtained at another pressure. Thermal decomposition analyses of Fe-, Mg-, and Ca-bearing carbonates at 12 mbar is required to enhance the understanding of the TEGA results at TEGA operating pressures. The objectives of this work are to (1) evaluate the thermal and evolved gas behavior of a suite of Fe-, Mg-, Ca-carbonate minerals at 1000 and 12 mbar and (2) discuss possible emplacement mechanisms for the Phoenix carbonate.

  2. Collisionless current sheet equilibria

    Neukirch, T.; Wilson, F.; Allanson, O.

    2018-01-01

    Current sheets are important for the structure and dynamics of many plasma systems. In space and astrophysical plasmas they play a crucial role in activity processes, for example by facilitating the release of magnetic energy via processes such as magnetic reconnection. In this contribution we will focus on collisionless plasma systems. A sensible first step in any investigation of physical processes involving current sheets is to find appropriate equilibrium solutions. The theory of collisionless plasma equilibria is well established, but over the past few years there has been a renewed interest in finding equilibrium distribution functions for collisionless current sheets with particular properties, for example for cases where the current density is parallel to the magnetic field (force-free current sheets). This interest is due to a combination of scientific curiosity and potential applications to space and astrophysical plasmas. In this paper we will give an overview of some of the recent developments, discuss their potential applications and address a number of open questions.

  3. Cholera Fact Sheet

    ... news-room/fact-sheets/detail/cholera","@context":"http://schema.org","@type":"Article"}; العربية 中文 français русский español ... that includes feedback at the local level and information-sharing at the global level. Cholera cases are ...

  4. Pseudomonas - Fact Sheet

    Public Health Agency

    2012-01-01

    Fact sheet on Pseudomonas, including:What is Pseudomonas?What infections does it cause?Who is susceptible to pseudomonas infection?How will I know if I have pseudomonas infection?How can Pseudomonas be prevented from spreading?How can I protect myself from Pseudomonas?How is Pseudomonas infection treated?

  5. NTPR Fact Sheets

    History Documents US Underground Nuclear Test History Reports NTPR Radiation Exposure Reports Enewetak Atoll Cleanup Documents TRAC About Who We Are Our Values History Locations Our Leadership Director Support Center Contact Us FAQ Sheet Links Success Stories Contracts Business Opportunities Current

  6. Production (information sheets)

    2007-01-01

    Documentation sheets: Geo energy 2 Integrated System Approach Petroleum Production (ISAPP) The value of smartness 4 Reservoir permeability estimation from production data 6 Coupled modeling for reservoir application 8 Toward an integrated near-wellbore model 10 TNO conceptual framework for "E&P

  7. Hibernia fact sheet

    Anon.

    1994-01-01

    This fact sheet gives details of the Hibernia oil field including its location, discovery date, oil company's interests in the project, the recoverable reserves of the two reservoirs, the production system used, capital costs of the project, and overall targets for Canadian benefit. Significant dates for the Hibernia project are listed. (UK)

  8. Ethanol Basics (Fact Sheet)

    2015-01-01

    Ethanol is a widely-used, domestically-produced renewable fuel made from corn and other plant materials. More than 96% of gasoline sold in the United States contains ethanol. Learn more about this alternative fuel in the Ethanol Basics Fact Sheet, produced by the U.S. Department of Energy's Clean Cities program.

  9. Phoenix dactylifera L. spathe essential oil: Chemical composition and repellent activity against the yellow fever mosquito

    Date palm, Phoenix dactylifera L. (Arecaceae), grows commonly in the Arabian Peninsula and is traditionally used to treat various diseases. The aim of the present study was to identify chemical composition of the essential oil and to investigate the repellent activity. The essential oil of P. dacty...

  10. Status of the PHOENIX electron cyclotron resonance charge breeder at ISOLDE, CERN.

    Barton, Charles; Cederkall, Joakim; Delahaye, Pierre; Kester, Oliver; Lamy, Thierry; Marie-Jeanne, Mélanie

    2008-02-01

    We report here on the last progresses made with the PHOENIX electron cyclotron resonance charge breeder test bench at ISOLDE. Recently, an experiment was performed to test the trapping of (61)Fe daughter nuclides from the decay of (61)Mn nuclides. Preliminary results are given.

  11. Industrial Design: A Phoenix Reborn from the Ashes of Technology Education--A Case History

    Greenwald, Martin; Feigler, Denis

    2009-01-01

    Like the "phoenix," technology education (TE) can, under the right circumstances, give life to new programs--curricula with different emphases and directions from technology education, yet sharing a common heritage: the belief that applied technology will continue to shape the world. How that shaping process takes place--and the problems that it…

  12. Tuhast tõusnud Phoenix jõudis Marsile elu võimalikkust uurima / Liisi Poll

    Poll, Liisi, 1980-

    2008-01-01

    Vt. ka Postimees : na russkom jazõke 27. mai, lk. 8. Marsile jõudnud NASA automaatjaam Phoenix maandus naaberplaneedi põhjapoolusele lähemale kui ükski inimese leiutatud masin kunagi varem. Lisa: Marsi uurimiste ajalugu

  13. 78 FR 24158 - Foreign-Trade Zone (FTZ) 75-Phoenix, Arizona; Notification of Proposed Production Activity...

    2013-04-24

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [B-33-2013] Foreign-Trade Zone (FTZ) 75-Phoenix... benefits on such items. Public comment is invited from interested parties. Submissions shall be addressed... Executive Secretary, Foreign-Trade Zones Board, Room 21013, U.S. Department of Commerce, 1401 Constitution...

  14. Historical evidence of the Spanish introduction of date palm (Phoenix dactylifera L., Arecaceae) into the Americas

    America’s date palm (Phoenix dactylifera L.) groves can be found from 36o N Lat. (USA) to 21o S Lat. (Chile) and from 63o W Long. (Venezuela) to 117o W Long. (USA), at elevations from sea level 2000 m (Colombia). However, successful production of ripe dates is possible only in the arid regions of Pe...

  15. Status of the PHOENIX electron cyclotron resonance charge breeder at ISOLDE, CERN

    Barton, Charles; Cederkall, Joakim; Delahaye, Pierre; Kester, Oliver; Lamy, Thierry; Marie-Jeanne, Melanie

    2008-01-01

    We report here on the last progresses made with the PHOENIX electron cyclotron resonance charge breeder test bench at ISOLDE. Recently, an experiment was performed to test the trapping of 61 Fe daughter nuclides from the decay of 61 Mn nuclides. Preliminary results are given

  16. 76 FR 30299 - Proposed Establishment of Class E Airspace; Kayenta, AZ

    2011-05-25

    ...-0393; Airspace Docket No. 11-AWP-2] Proposed Establishment of Class E Airspace; Kayenta, AZ AGENCY... action proposes to establish Class E Airspace at Kayenta Airport, Kayenta, AZ. Controlled airspace is...) standard instrument approach procedures at Kayenta Airport. The FAA is proposing this action to enhance the...

  17. 76 FR 3570 - Proposed Amendment of Class E Airspace; Taylor, AZ

    2011-01-20

    ...-1189; Airspace Docket No. 10-AWP-19] Proposed Amendment of Class E Airspace; Taylor, AZ AGENCY: Federal... proposes to modify Class E airspace at Taylor Airport, Taylor, AZ. Controlled airspace is necessary to accommodate aircraft using the CAMBO One Departure Area Navigation (RNAV) out of Taylor Airport. The FAA is...

  18. Rubella - Fact Sheet for Parents

    ... and 4 through 6 years Fact Sheet for Parents Color [2 pages] Español: Rubéola The best way ... according to the recommended schedule. Fact Sheets for Parents Diseases and the Vaccines that Prevent Them Chickenpox ...

  19. Influence of the Composition of the Hank’s Balanced Salt Solution on the Corrosion Behavior of AZ31 and AZ61 Magnesium Alloys

    Tkacz, J.; Slouková, K.; Minda, J.; Drábiková, J.; Fintová, Stanislava; Doležal, P.; Wasserbauer, J.

    2017-01-01

    Roč. 7, č. 11 (2017), č. článku 465. ISSN 2075-4701 Institutional support: RVO:68081723 Keywords : magnesium alloy * AZ31 * AZ61 * HBSS * HBSS+ * EIS * potentiodynamic test Subject RIV: JK - Corrosion ; Surface Treatment of Materials OBOR OECD: Coating and films Impact factor: 1.984, year: 2016 http://www.mdpi.com/2075-4701/7/11/465

  20. Development of AZS refractories for the glass industry

    Guzman, A.M.; Rodriguez, P.

    2004-01-01

    Refractory materials can support high temperatures, thermal strength and the contact with aggressive environments, for this reason they are widely used in the cement, glass and steel industry. Commercial AZS (alumina-zirconia-silica) refractories are a good alternative in refractory materials for the glass industry' because they can support the aggressive conditions during liquid processing of glass. However, another problem encountered in glass industry is contamination by refractory' material that fall into the molten glass, which can produce a series of defects in the final product. This research was conducted to develop new formulations of AZS refractories with different amounts of ZrO 2 with the purpose of improving the characteristics, properties and the work conditions in the glass melting furnaces and, at the same time, lower the costs this type of refractories. The results obtained indicate that the composition with low content of ZrO 2 can provide better properties than the commercial product, with some modifications in the particle size distribution. Copyright (2004) AD-TECH - International Foundation for the Advancement of Technology Ltd

  1. Influence of the Composition of the Hank’s Balanced Salt Solution on the Corrosion Behavior of AZ31 and AZ61 Magnesium Alloys

    Jakub Tkacz

    2017-11-01

    Full Text Available The electrochemical corrosion characteristics of AZ31 and AZ61 magnesium alloys were analyzed in terms of potentiodynamic tests and electrochemical impedance spectroscopy. The influence of the solution composition and material surface finish was examined also through the analysis of corrosion products created on the samples’ surface after electrochemical measurements in terms of scanning electron microscopy using energy-dispersive spectroscopy. Obtained data revealed the differences in the response of the magnesium alloys to enriched Hank’s Balanced Salt Solution—HBSS+ (with Mg2+ and Ca2+ ions and Hank’s Balanced Salt Solution—HBSS (without Mg2+ and Ca2+ ions. Both examined alloys exhibited better corrosion resistance from the thermodynamic and kinetic point of view in the enriched HBSS+. AZ61 magnesium alloy reached higher values of polarization resistance than AZ31 magnesium alloy in both the used corrosion solutions. Phosphate-based corrosion products were characteristic for the AZ31 and AZ61 alloys tested in the HBSS (without Mg2+ and Ca2+ ions. The combination of phosphate-based corrosion products and clusters of MgO and Mg(OH2 was typical for the surface of samples tested in the enriched HBSS+ (with Mg2+ and Ca2+ ions. Pitting corrosion attack was observed only in the case of enriched HBSS+.

  2. Effect of Hydraulic Pressure on Warm Hydro Mechanical Deep Drawing of Magnesium Alloy Sheet

    Liu, Wei; Wu, Linzhi; Yuan, Shijian

    The uniaxial tensile test and hydraulic bulging test of AZ31 magnesium alloy sheets were applied to study the influence of temperature on the material properties and obtain the forming limit curves at different temperatures. Numerical simulations of warm hydro mechanical deep drawing were carried out to investigate the effect of hydraulic pressure on the formability of a cylindrical cup, and the simplified hydraulic pressure profiles were used to simulate the loading procedure of hydraulic pressure. The optimal hydraulic pressure at different temperatures were given and verified by experimental studies at temperature 100°C and 170V.

  3. In Vitro Studies on the Degradability, Bioactivity, and Cell Differentiation of PRP/AZ31B Mg Alloys Composite Scaffold

    Jian Zou

    2017-01-01

    Full Text Available In recent years, more and more methods have been developed to improve the bioactivity of the biodegradable materials in bone tissue regeneration. In present study, we used rat mesenchymal stem cells (rMSCs to evaluate the outcomes of Mg alloys (AZ31B, Magnesium, and Aluminum and Platelet-rich plasma (PRP/Mg alloys on rMSCs biocompatibility and osteogenic differentiation. Water absorption experiments indicated that both bare AZ31B and PRP/AZ31B were capable of absorbing large amounts of water. But the water absorption ratio for PRP/AZ31B was significantly higher than that for bare AZ31B. The degradability experiments implied that both samples degraded at same speed. rMSCs on the surface of AZ31B distributed more and better than those on the AZ31B scaffold. In ALP activity experiment, the activity of rMSCs on the PRP/AZ31B was markedly higher than that on the AZ31B scaffolds on the 7th day and 14th day. qRT-PCR also showed that OPN and OCN were expressed in both samples. OPN and OCN expression in PRP/AZ31B sample were higher than those in bare AZ31B samples. In summary, the in vitro study implied that AZ31B combined with PRP could remarkably improve cell seeding, attachment, proliferation, and differentiation.

  4. Unravelling the magmatic system beneath a monogenetic volcanic complex (Jagged Rocks Complex, Hopi Buttes, AZ, USA)

    Re, G.; Palin, J. M.; White, J. D. L.; Parolari, M.

    2017-12-01

    The Jagged Rocks complex is the eroded remnant of the plumbing systems of closely spaced monogenetic alkaline volcanic centres in the southern Hopi Buttes Volcanic Field (AZ, USA). It contains different clinopyroxene populations with distinctive textures and geochemical patterns. In the Northwestern part of the complex, which exposes the best developed system of conduits, most of the clinopyroxenes consist of large- to medium-sized resorbed cores overgrown by euhedral rims (type 1), small moderately resorbed greenish cores with the same overgrown rims (type 2), and phlogopite as an accessory phase. By contrast, in the Southern part of the complex the majority of clinopyroxenes are euhedral with oscillatory zonation (type 3) and are accompanied by minor euhedral olivine. The differences between these mineral assemblages indicate a composite history of crystallization and magmatic evolution for the two parts of the complex, governed by different mechanisms and ascent patterns from a single source at 50 km depth (16 kbar). The Northwest system preserves a high-pressure assemblage that cooled rapidly from near-liquidus conditions, suggesting direct ascent from the source to the surface at high-to-moderate transport rates (average 1.25 m/s). By contrast, the Southern system represents magma that advanced upward at much lower overall ascent rates, stalling at times to form small-volume mid-crustal storage zones (e.g., sills or a network of sheeted intrusions); this allowed the re-equilibration of the magma at lower pressure ( 30 km; 8 kbar), and led to nucleation and growth of euhedral clinopyroxene and olivine phenocrysts.

  5. Film sheet cassette

    1981-01-01

    A novel film sheet cassette is described for handling CAT photographic films under daylight conditions and facilitating their imaging. A detailed description of the design and operation of the cassette is given together with appropriate illustrations. The resulting cassette is a low-cost unit which is easily constructed and yet provides a sure light-tight seal for the interior contents of the cassette. The individual resilient fingers on the light-trap permit the ready removal of the slide plate for taking pictures. The stippled, non-electrostatic surface of the pressure plate ensures an air layer and free slidability of the film for removal and withdrawal of the film sheet. The advantage of the daylight system is that a darkroom need not be used for inserting and removing the film in and out of the cassette resulting in a considerable time saving. (U.K.)

  6. Dictionary of engines. The internal combustion engine from A-Z; Lexikon Motorentechnik. Der Verbrennungsmotor von A-Z

    Schaefer, F. (ed.); Basshuysen, R. van

    2004-04-01

    This dictionary describes current engine technology and gives an outlook to the future. Cross-references, broader and narrower terms ensure optimal user guidance. Entries do not stand alone but provide content-oriented information. About 4,500 terms are included from A-Z, providing an outline of subjects like exhaust systems, acoustics, supercharging, combustion chamber, injection systems, control, flame propagation, mixing, catalytic converters, pistons, fuels, cooling, crank casing, stratified charging, lambda control, camshaft, oil, particulate filters, sensors/actuators, pollutants, valves, combustion processes, efficiency, ignition, cylinder head. The dictionary is for development engineers in the motor car industry, in component and system development in the supply industry, university teachers and students, foremen in motor car repair shops, etc. (orig.) [German] Das Lexikon Motorentechnik ist ein Nachschlagewerk, das die aktuelle Motorentechnik umfassend beschreibt und Ausblicke in der Zukunft ermoeglicht. Das ausgefeilte System aus Querverweisen fuehrt alle Unterbegriffe zum Hauptbegriff und ermoeglicht so eine optimale Benutzerfuehrung. Dadurch stehen die Stichwoerter nicht isoliert, sondern es werden inhaltlich zusammenhaengende Betrachtungen moeglich. Der Inhalt umfasst 4 500 Begriffe von A-Z wie z.B.: Abgastechnik, Akustik, Aufladung, Brennraum, Einspritzsysteme, Elektronische Motorsteuerung, Flammenausbreitung, Gemischbildung, Katalysator, Kolben, Kraftstoff, Kuehlung, Kurbelgehaeuse, Kurbeltrieb, Ladungswechsel, Lambda-Regelung, Nockenwelle, Oel, Partikelfilter, Sensoren/Aktuatoren, Schadstoffe, Ventiltrieb, Verbrennungsverfahren, Wirkungsgrad, Zuendung, Zylinderkopf. Die Zielgruppen waeren Ingenieure in Motoren- und Fahrzeugentwicklung der Automobilindustrie, Ingenieure in der Komponenten- und Systementwicklung der Zuliefererindustrie, Professoren und Studenten an Hochschulen mit Schwerpunkt Kraftfahrzeugtechnik, Meister in Kfz-Werkstaetten. (orig.)

  7. Clean Cities Fact Sheet

    2004-01-01

    This fact sheet explains the Clean Cities Program and provides contact information for all coalitions and regional offices. It answers key questions such as: What is the Clean Cities Program? What are alternative fuels? How does the Clean Cities Program work? What sort of assistance does Clean Cities offer? What has Clean Cities accomplished? What is Clean Cities International? and Where can I find more information?

  8. Information sheets on energy

    2004-01-01

    These sheets, presented by the Cea, bring some information, in the energy domain, on the following topics: the world energy demand and the energy policy in France and in Europe, the part of the nuclear power in the energy of the future, the greenhouse gases emissions and the fight against the greenhouse effect, the carbon dioxide storage cost and the hydrogen economy. (A.L.B.)

  9. Biomolecular Science (Fact Sheet)

    2012-04-01

    A brief fact sheet about NREL Photobiology and Biomolecular Science. The research goal of NREL's Biomolecular Science is to enable cost-competitive advanced lignocellulosic biofuels production by understanding the science critical for overcoming biomass recalcitrance and developing new product and product intermediate pathways. NREL's Photobiology focuses on understanding the capture of solar energy in photosynthetic systems and its use in converting carbon dioxide and water directly into hydrogen and advanced biofuels.

  10. Sheet pinch devices

    Anderson, O.A.; Baker, W.R.; Ise, J. Jr.; Kunkel, W.B.; Pyle, R.V.; Stone, J.M.

    1958-01-01

    Three types of sheet-like discharges are being studied at Berkeley. The first of these, which has been given the name 'Triax', consists of a cylindrical plasma sleeve contained between two coaxial conducting cylinders A theoretical analysis of the stability of the cylindrical sheet plasma predicts the existence of a 'sausage-mode' instability which is, however, expected to grow more slowly than in the case of the unstabilized linear pinch (by the ratio of the radial dimensions). The second pinch device employs a disk shaped discharge with radial current guided between flat metal plates, this configuration being identical to that of the flat hydromagnetic capacitor without external magnetic field. A significant feature of these configurations is the absence of a plasma edge, i.e., there are no regions of sharply curved magnetic field lines anywhere in these discharges. The importance of this fact for stability is not yet fully investigated theoretically. As a third configuration a rectangular, flat pinch tube has been constructed, and the behaviour of a flat plasma sheet with edges is being studied experimentally

  11. Martian Multimedia: The Agony and Ecstasy of Communicating Real-Time, Authentic Science During the Phoenix Mars Mission

    Bitter, C.; Buxner, S. R.

    2009-03-01

    The Phoenix Mars Mission faced robust communication challenges requiring real-time solutions. Managing the message from Mars and ensuring the highest quality of science data and news releases were our top priorities during mission surface operations.

  12. 241-AY/AZ waste storage tanks: Supplemental gravity load analysis. Volume 1

    Baliga, R.

    1994-01-01

    An analysis of the 241SY tanks performed by ADVENT(1994b) to resolve dome overload issues indicated that the tank can sustain the dome loads resulting from additional soil overburden depth, increased soil density, and increased concentrated load. Similar issues exist for the 241AY/AZ tanks and therefore, an interim analysis of the 241AY/AZ tanks is presented herein. The scope of this effort is to review and compare all design drawings pertaining to the 241AY and 241AZ tanks with those pertaining to the 241SY tanks; to modify the axisymmetric model of the 241SY tanks to represent the 241AY/AZ tanks; and to evaluate the effect of additional dome load on the 241AY/AZ tanks by performing a structural analysis for gravity loads (dead load + live load). ADVENTS's additional scope of work is to perform a qualitative evaluation of the 241AY/AZ tanks for seismic and thermal loadings (Vollert 1982 and Blume 1971). This qualitative evaluation does not include any detailed finite element analysis of the tanks. The following design-based gravity loading conditions are used in this interim analysis of the 241AY/AZ tanks to determine a baseline for the tank stresses or section loads

  13. Histone H2A.Z is essential for estrogen receptor signaling

    Gévry, Nicolas; Hardy, Sara; Jacques, Pierre-Étienne; Laflamme, Liette; Svotelis, Amy; Robert, François; Gaudreau, Luc

    2009-01-01

    Incorporation of H2A.Z into the chromatin of inactive promoters has been shown to poise genes for their expression. Here we provide strong evidence that H2A.Z is incorporated into the promoter regions of estrogen receptor (ERα) target genes only upon gene induction, and that, in a cyclic pattern. Moreover, members of the human H2A.Z-depositing complex, p400, also follow the same gene recruitment kinetics as H2A.Z. Importantly, cellular depletion of H2A.Z or p400 leads to a severe defect in estrogen signaling, including loss of estrogen-specific cell proliferation. We find that incorporation of H2A.Z within TFF1 promoter chromatin allows nucleosomes to adopt preferential positions along the DNA translational axis. Finally, we provide evidence that H2A.Z is essential to allow estrogen-responsive enhancer function. Taken together, our results provide strong mechanistic insight into how H2A.Z regulates ERα-mediated gene expression and provide a novel link between H2A.Z–p400 and ERα-dependent gene regulation and enhancer function. PMID:19515975

  14. About some corrosion mechanisms of AZ91D magnesium alloy

    Ballerini, Gaia; Bardi, Ugo; Bignucolo, Roberto; Ceraolo, Giuseppe

    2005-01-01

    The present work is dedicated to a study of the corrosion resistance of AZ91D (91% Mg) alloy in wet environments. Three industrial alloys obtained by die-casting or sand casting were subjected to salt spray corrosion tests (ASTM-B117 standard) and immersion tests. Weight loss kinetic curves were measured. Surface analysis was performed by X-ray photoelectron diffraction (XPS). After corrosion the sand cast alloy presents a surface mainly enriched in hydroxides and carbonates while the die-cast alloy presents a surface enriched also in mixed Mg-Al oxides. The quantitative analysis of the rate Mg/Al shows an enrichment in aluminium for the die-cast alloys in comparison to the sand cast alloy

  15. High speed cutting of AZ31 magnesium alloy

    Liwei Lu

    2016-06-01

    Full Text Available Using LBR-370 numerical control lathe, high speed cutting was applied to AZ31 magnesium alloy. The influence of cutting parameters on microstructure, surface roughness and machining hardening were investigated by using the methods of single factor and orthogonal experiment. The results show that the cutting parameters have an important effect on microstructure, surface roughness and machine hardening. The depth of stress layer, roughness and hardening present a declining tendency with the increase of the cutting speed and also increase with the augment of the cutting depth and feed rate. Moreover, we established a prediction model of the roughness, which has an important guidance on actual machining process of magnesium alloy.

  16. commodity: el caso del mercado internacional del azúcar

    Julio César Alonso

    2013-01-01

    Full Text Available Este trabajo estudia el comportamiento estacional de los precios internacionales del azúcar transados en Nueva York y Londres. Para este caso, empleando pruebas de raíces estacionales y una muestra mensual desde enero de 1989 hasta diciembre de 2010, se encuentra la existencia de un comportamiento estacional estocástico no estacionario. Dicha conducta implica que un “verano” se puede convertir en un “invierno”, resultado que no había sido documentado previamente en estos mercados. Por otro lado, empleando dicho hallazgo, los resultados muestran que es posible construir un modelo autorregresivo de media móvil que se comporta relativamente mejor al pronosticar el precio frente a un modelo que no tiene en cuenta dicho tipo de estacionalidad.

  17. Corrosion resistance of titanium ion implanted AZ91 magnesium alloy

    Liu Chenglong; Xin Yunchang; Tian Xiubo; Zhao, J.; Chu, Paul K.

    2007-01-01

    Degradable metal alloys constitute a new class of materials for load-bearing biomedical implants. Owing to their good mechanical properties and biocompatibility, magnesium alloys are promising in degradable prosthetic implants. The objective of this study is to improve the corrosion behavior of surgical AZ91 magnesium alloy by titanium ion implantation. The surface characteristics of the ion implanted layer in the magnesium alloys are examined. The authors' results disclose that an intermixed layer is produced and the surface oxidized films are mainly composed of titanium oxide with a lesser amount of magnesium oxide. X-ray photoelectron spectroscopy reveals that the oxide has three layers. The outer layer which is 10 nm thick is mainly composed of MgO and TiO 2 with some Mg(OH) 2 . The middle layer that is 50 nm thick comprises predominantly TiO 2 and MgO with minor contributions from MgAl 2 O 4 and TiO. The third layer from the surface is rich in metallic Mg, Ti, Al, and Ti 3 Al. The effects of Ti ion implantation on the corrosion resistance and electrochemical behavior of the magnesium alloys are investigated in simulated body fluids at 37±1 deg. C using electrochemical impedance spectroscopy and open circuit potential techniques. Compared to the unimplanted AZ91 alloy, titanium ion implantation significantly shifts the open circuit potential (OCP) to a more positive potential and improves the corrosion resistance at OCP. This phenomenon can be ascribed to the more compact surface oxide film, enhanced reoxidation on the implanted surface, as well as the increased β-Mg 12 Al 17 phase

  18. Dense sheet Z-pinches

    Tetsu, Miyamoto

    1999-01-01

    The steady state and quasi-steady processes of infinite- and finite-width sheet z-pinches are studied. The relations corresponding to the Bennett relation and Pease-Braginskii current of cylindrical fiber z-pinches depend on a geometrical factor in the sheet z-pinches. The finite-width sheet z-pinch is approximated by a segment of infinite-width sheet z-pinch, if it is wide enough, and corresponds to a number of (width/thickness) times fiber z-pinch plasmas of the diameter that equals the sheet thickness. If the sheet current equals this number times the fiber current, the plasma created in the sheet z-pinches is as dense as in the fiber z-pinches. The total energy of plasma and magnetic field per unit mass is approximately equal in both pinches. Quasi-static transient processes are different in several aspects from the fiber z-pinch. No radiation collapse occurs in the sheet z-pinch. The stability is improved in the sheet z-pinches. The fusion criterions and the experimental arrangements to produce the sheet z-pinches are also discussed. (author)

  19. Corrosion properties and corrosion evolution of as-cast AZ91 alloy with rare earth yttrium

    Luo, T.J.; Yang, Y.S.

    2011-01-01

    Highlights: → Minor addition of Y will increase the corrosion resistance of AZ91 alloy, and 0.3 wt.% Y is the optimum addition. → A film composed of Mg(OH) 2 , MgCO 3 , Al(OH) 3 and Al 2 O 3 is formed on the surface of AZ91 alloy with rare earth Y free. → The film of AZ91 alloy with 0.3 wt.% Y is mainly composed of Mg(OH) 2 and MgCO 3 without any Al(OH) 3 and Al 2 O 3 . → The relative quantity of MgCO 3 in the surface film of AZ91 + 0.3 wt.% Y is bigger than that of AZ91 alloy with Y free. → Y 2 O 3 phase is found in the surface film of alloy III, which benefits to stabilize the surface film. -- Abstract: The corrosion resistance property and the corrosion evolution of as-cast AZ91 alloy with rare earth Y addition are investigated by using immersion tests, electrochemical impedance spectroscopy (EIS), and X-ray photoelectron spectroscopy (XPS). The results show that the proper amount of Y in the alloys can improve the corrosion resistance of AZ91 alloys effectively. With the increment of Y, the corrosion rate of the modified AZ91 alloys by Y addition was markedly less than that of AZ91 alloy. The corrosion rate of AZ91 alloy with 0.3 wt.% Y was the slightest, but further addition of Y content over 0.3 wt.% make the corrosion heavier. The XPS analysis suggests that the compound film of AZ91 alloy with 0.3 wt.% Y is mainly composed of Mg(OH) 2 and MgCO 3 without any Al(OH) 3 and Al 2 O 3 , in addition, Y 2 O 3 phase is found in the compound film of AZ91 alloy with 0.3 wt.% Y, which benefits to stabilize the surface film.

  20. Project W-211 Initial Tank Retrieval Systems (ITRS) Description of Operations for 241-AZ-102

    BRIGGS, S.R.

    2000-02-25

    The primary purpose of the Initial Tank Retrieval Systems (ITRS) is to provide systems for retrieval of radioactive wastes stored in underground double-shell tanks (DSTs) for transfer to alternate storage, evaporation, pretreatment or treatment, while concurrently reducing risks associated with safety watch list and other DSTs. This Description of Operation (DOO) defines the control philosophy for the waste retrieval system for Tank 241-AZ-102 (AZ-102). This DOO provides a basis for the detailed design of the Project W-211 Retrieval Control System (RCS) for AZ-102 and also establishes test criteria for the RCS.

  1. Microstructure and Aging Behavior of Nonflammable AZ91D Mg Alloy

    Seok Hong Min; Tae Kwon Ha

    2014-01-01

    Phase equilibria of AZ91D Mg alloys for nonflammable use, containing Ca and Y, were carried out by using FactSage® and FTLite database, which revealed that solid solution treatment could be performed at temperatures from 400 to 450oC. Solid solution treatment of AZ91D Mg alloy without Ca and Y was successfully conducted at 420oC and supersaturated microstructure with all beta phase resolved into matrix was obtained. In the case of AZ91D Mg alloy with some Ca and Y; howeve...

  2. Project W-211 Initial Tank Retrieval Systems (ITRS) Description of Operations for 241-AZ-102

    BRIGGS, S.R.

    2000-01-01

    The primary purpose of the Initial Tank Retrieval Systems (ITRS) is to provide systems for retrieval of radioactive wastes stored in underground double-shell tanks (DSTs) for transfer to alternate storage, evaporation, pretreatment or treatment, while concurrently reducing risks associated with safety watch list and other DSTs. This Description of Operation (DOO) defines the control philosophy for the waste retrieval system for Tank 241-AZ-102 (AZ-102). This DOO provides a basis for the detailed design of the Project W-211 Retrieval Control System (RCS) for AZ-102 and also establishes test criteria for the RCS

  3. Punchless Drawing of Magnesium Alloy Sheet under Cold Condition and its Computation

    Yamashita, Minoru; Hattori, Toshio; Sato, Joji

    2011-01-01

    The punchless drawing with Maslennikov's technique was applied to the circular cup drawing of magnesium alloy AZ31B sheet under cold condition. The elastic rubber ring was used instead of the 'hard' punch, where the compressed ring dragged the sheet inward the die cavity. Attainable circumferential strain of the blank was increased by this technique with repetitive drawing operation. Thickness of the rubber pad affected little the attainable strain. The shape appearance became better when a harder rubber was used. The cup forming by single drawing operation was also tested using a small die shoulder radius. The LDR of 1.250 was obtained with the straight cup wall. Further, the computation of the punchless drawing was also conducted for the single drawing operation. The computed deformation pattern was well consistent with the corresponding experimental result.

  4. The Effects of Plastic Anisotropy in Warm and Hot Forming of Magnesium Sheet Materials

    Taleff, Eric M.; Antoniswamy, Aravindha R.; Carpenter, Alexander J.; Yavuz, Emre

    Mg alloy sheet materials often exhibit plastic anisotropy at room temperature as a result of the limited slip systems available in the HCP lattice combined with a commonly strong basal texture. Less well studied is plastic anisotropy developed at the elevated temperatures associated with warm and hot forming. At these elevated temperatures, particularly above 200°C, the activation of additional slip systems significantly increases ductility. However, plastic anisotropy is also induced at elevated temperatures by a strong crystallographic texture, and it can require an accounting in material constitutive models to achieve accurate forming simulations. The type and degree of anisotropy under these conditions depend on both texture and deformation mechanism. The current understanding of plastic anisotropy in Mg AZ31B and ZEK100 sheet materials at elevated temperatures is reviewed in this article. The recent construction of material forming cases is also reviewed with strategies to account for plastic anisotropy in forming simulations.

  5. Effect of thermal treatment on the interface-correlated mechanical properties of Al-Mg dissimilar metallic sheets

    Lee, Su Eun; Lee, Kwang Seok; Kwon, Yong Nam [Korea Insiute of Materials Science, Changwon (Korea, Republic of); Kim, Min Jung [Korea Clad Tech. Co. Ltd., Daegu (Korea, Republic of)

    2014-01-15

    The influence of annealing treatment on the interface-correlated microstructural evolution and subsequent mechanical properties of an Al1050/AZ31B clad sheet was systematically investigated. A scanning electron microscope with an attached energy dispersive spectroscopy revealed that diffusive layer consisted of γ (Mg{sub 1}7Al{sub 1}2), and β (Mg{sub 2}Al{sub 3}) phases was generated and grown with increasing annealing time and temperature. Mechanical properties were evaluated by uniaxial tensile and peel tests. Improvement of bonding strength between Al1050 and AZ31B by feasible annealing seemed to be strongly related to the generation of metallurgical bonding by a diffusive intermetallic compound layer whose overall thickness was limited to below 1.4 μm.

  6. Perforation of metal sheets

    Steenstrup, Jens Erik

    simulation is focused on the sheet deformation. However, the effect on the tool and press is included. The process model is based on the upper bound analysis in order to predict the force progress and hole characteristics etc. Parameter analyses are divided into two groups, simulation and experimental tests......The main purposes of this project are:1. Development of a dynamic model for the piercing and performation process2. Analyses of the main parameters3. Establishing demands for process improvements4. Expansion of the existing parameter limitsThe literature survey describes the process influence...

  7. Destruction of the Phoenix/Hibiscus and Barringtonia racemosa Communities at Richards Bay, Natal, South Africa

    P. J. Weisser

    1982-10-01

    Full Text Available The destruction of the Phoenix!Hibiscus and Barringtonia racemosa Communities described by Venter in 1972 on the southern shores of Richards Bay is reported. The cause was the artificial openingof a new mouth about 5,5 km south of the original mouth, which increased tidal range and salinity. These swamp communities occupied a narrow band about 6 ha in area behind the Bruguiera gymnorrhiza Community. An estimated 95 % of the communities was affected and only on the landward border were some isolated remnants of species such as Acrostichum aureum, Hibiscus tiliaceus and Phoenix reclinata detected .Young stands of  Phragmites australis, seedlings of  Bruguiera gymnorrhiza and Avicennia marina and epipelic algae are recoIonizing the affected area.

  8. Implementation of a quality management system at the PHOENIX facility (CryoMaK)

    Urbach, Elisabeth; Bagrets, Nadezda; Weiss, Klaus-Peter

    2013-01-01

    Within a variety of mechanical tests in the Cryogenic Material Test Facility Karlsruhe (CryoMaK) at Karlsruhe Institute of Technology (KIT) the PHOENIX facility was prepared for multiple standard tensile tests in liquid helium, liquid nitrogen and at room temperature. With the multiple specimens holder 10 specimens can be tested within one cool down one after another. A quality management system is needed for ensuring reproducible preconditions. For the guarantee of the competence of the laboratory and the measurement equipment, a quality management system was implemented and prepared for accreditation according to DIN EN ISO/IEC 17025 (ISO 17025). The implementation of a quality management system allows high precision test results included the estimation of measurement uncertainty. This paper gives an overview of the management and technical requirements for the accreditation of the PHOENIX testing facility

  9. Implementation of a quality management system at the PHOENIX facility (CryoMaK)

    Urbach, Elisabeth, E-mail: elisabeth.urbach@kit.edu; Bagrets, Nadezda; Weiss, Klaus-Peter

    2013-10-15

    Within a variety of mechanical tests in the Cryogenic Material Test Facility Karlsruhe (CryoMaK) at Karlsruhe Institute of Technology (KIT) the PHOENIX facility was prepared for multiple standard tensile tests in liquid helium, liquid nitrogen and at room temperature. With the multiple specimens holder 10 specimens can be tested within one cool down one after another. A quality management system is needed for ensuring reproducible preconditions. For the guarantee of the competence of the laboratory and the measurement equipment, a quality management system was implemented and prepared for accreditation according to DIN EN ISO/IEC 17025 (ISO 17025). The implementation of a quality management system allows high precision test results included the estimation of measurement uncertainty. This paper gives an overview of the management and technical requirements for the accreditation of the PHOENIX testing facility.

  10. Genetic Diversity of Iraqi Date Palm (Phoenix ‎dactylifera L.) by using RAPD Technique

    Muhanned Abdul Hasan Kareem; Ali Hmood Al-Saadi ‎; Hassan Fadhil Naji

    2018-01-01

    In this study provided all molecular markers of Random amplified polymorphic (RAPD) successfully with the sixty five Iraqi date palm (Phoenix dactylifera L.) cultivars, which collected from Hilla city in Iraq, to determine fingerprinting, polymorphic value, and relationships among varieties of date palm cultivars, and also with the same type of cultivars. Data analysis of ten RAPD has been revealed. Number of amplified DNA fragments were (592) bands, polymorphism per all primers were (%64.2),...

  11. Genetic Diversity of Iraqi Date Palm (Phoenix ‎dactylifera L.) by using RAPD Technique

    Muhanned Abdul Hasan; Ali ‎ Hmood Al-Saadi; Hassan Fadhil Naji

    2017-01-01

    In this study provided all molecular markers of Random amplified polymorphic (RAPD) successfully with the sixty five Iraqi date palm (Phoenix dactylifera L.) cultivars, which collected from Hilla city in Iraq, to determine fingerprinting, polymorphic value, and relationships among varieties of date palm cultivars, and also with the same type of cultivars. Data analysis of ten RAPD has been revealed. Number of amplified DNA fragments were (592) bands, polymorphism per all primers were (%64.2),...

  12. Phoenix Miracles in Emerging Markets: Recovering without Credit from Systemic Financial Crises

    Guillermo A. Calvo; Alejandro Izquierdo; Ernesto Talvi

    2006-01-01

    Using a sample of emerging markets that are integrated into global bond markets, we analyze the collapse and recovery phase of output collapses that coincide with systemic sudden stops, defined as periods of skyrocketing aggregate bond spreads and large capital flow reversals. Our findings indicate the presence of a very similar pattern across different episodes: output recovers with virtually no recovery in either domestic or foreign credit, a phenomenon that we call Phoenix Miracle, where o...

  13. Date palm (Phoenix dactylifera)dispersal to the Americas: Historical evidence of the Spanish introduction

    Date palm (Phoenix dactylifera) groves are found in the Americas from the south-west USA (36°N lat.) to Chile (21°S lat.) and eastward to the Caribbean Islands; from Venezuela, 63°W long. to 117°W long. (USA) and at elevations from 0-2,000 m. However, successful production of ripe dates is possible ...

  14. The ecological importance of mixed-severity fires: Nature's phoenix [Book Review

    Carolyn H. Sieg

    2016-01-01

    The stated goal of a recent book, The Ecological Importance of Mixed-Severity Fires: Nature’s Phoenix, edited by Dominick A. DellaSala and Chad T. Hansen, is to provide a global reference on the benefits of mixed- and high-severity fires. Note that the goal is not to provide an objective reference on the ecological aspects of mixed- and high-severity fires. Rather, the...

  15. Experiments on sheet metal shearing

    Gustafsson, Emil

    2013-01-01

    Within the sheet metal industry, different shear cutting technologies are commonly used in several processing steps, e.g. in cut to length lines, slitting lines, end cropping etc. Shearing has speed and cost advantages over competing cutting methods like laser and plasma cutting, but involves large forces on the equipment and large strains in the sheet material.Numerical models to predict forces and sheared edge geometry for different sheet metal grades and different shear parameter set-ups a...

  16. Visual Analytics for the Food-Water-Energy Nexus in the Phoenix Active Management Area

    Maciejewski, R.; Mascaro, G.; White, D. D.; Ruddell, B. L.; Aggarwal, R.; Sarjoughian, H.

    2016-12-01

    The Phoenix Active Management Area (AMA) is an administrative region of 14,500 km2 identified by the Arizona Department of Water Resources with the aim of reaching and maintaining the safe yield (i.e. balance between annual amount of groundwater withdrawn and recharged) by 2025. The AMA includes the Phoenix metropolitan area, which has experienced a dramatic population growth over the last decades with a progressive conversion of agricultural land into residential land. As a result of these changes, the water and energy demand as well as the food production in the region have significantly evolved over the last 30 years. Given the arid climate, a crucial role to support this growth has been the creation of a complex water supply system based on renewable and non-renewable resources, including the energy-intensive Central Arizona Project. In this talk, we present a preliminary characterization of the evolution in time of the feedbacks between food, water, and energy in the Phoenix AMA by analyzing secondary data (available from water and energy providers, irrigation districts, and municipalities), as well as satellite imagery and primary data collected by the authors. A preliminary visual analytics framework is also discussed describing current design practices and ideas for exploring networked components and cascading impacts within the FEW Nexus. This analysis and framework represent the first steps towards the development of an integrated modeling, visualization, and decision support infrastructure for comprehensive FEW systems decision making at decision-relevant temporal and spatial scales.

  17. In aftermath of financial investigation Phoenix VA employee demoted after her testimony

    Robbins RA

    2013-03-01

    Full Text Available No abstract available. Article truncated after 150 words. A previous Southwest Journal of Pulmonary and Critical Care Journal editorial commented on fiscal mismanagement at the Department of Veterans Affairs (VA Medical Center in Phoenix (1. Now Paula Pedene, the former Phoenix VA public affairs officer, claims she was demoted for testimony she gave to the VA Inspector General’s Office (OIG regarding that investigation (2. In 2011, the OIG investigated the Phoenix VA for excess spending on private care of patients (3. The report blamed systemic failures for controls so weak that $56 million in medical fees were paid during 2010 without adequate review. The report particularly focused on one clinician assigned by the Chief of Staff to review hundreds of requests per week and the intensive care unit physicians for transferring patients to chronic ventilator units (1,3. After the investigation, the director and one of the associate directors left the VA and the chief of staff was promoted …

  18. Benchmarking of the PHOENIX-P/ANC [Advanced Nodal Code] advanced nuclear design system

    Nguyen, T.Q.; Liu, Y.S.; Durston, C.; Casadei, A.L.

    1988-01-01

    At Westinghouse, an advanced neutronic methods program was designed to improve the quality of the predictions, enhance flexibility in designing advanced fuel and related products, and improve design lead time. Extensive benchmarking data is presented to demonstrate the accuracy of the Advanced Nodal Code (ANC) and the PHOENIX-P advanced lattice code. Qualification data to demonstrate the accuracy of ANC include comparison of key physics parameters against a fine-mesh diffusion theory code, TORTISE. Benchmarking data to demonstrate the validity of the PHOENIX-P methodologies include comparison of physics predictions against critical experiments, isotopics measurements and measured power distributions from spatial criticals. The accuracy of the PHOENIX-P/ANC Advanced Design System is demonstrated by comparing predictions of hot zero power physics parameters and hot full power core follow against measured data from operating reactors. The excellent performance of this system for a broad range of comparisons establishes the basis for implementation of these tools for core design, licensing and operational follow of PWR [pressurized water reactor] cores at Westinghouse

  19. McMurdo Dry Valleys, Antarctica - A Mars Phoenix Mission Analog

    Tamppari, L. K.; Anderson, R. M.; Archer, D.; Douglas, S.; Kounaves, S. P.; McKay, C. P.; Ming, Douglas W.; Moore, Q.; Quinn, J. E.; Smith, P. H.; hide

    2010-01-01

    The Phoenix mission (PHX; May 25 - Nov. 2, 2008) studied the north polar region of Mars (68deg N) to understand the history of water and potential for habitability. Phoenix carried with it a wet chemistry lab (WCL) capable of determining the basic solution chemistry of the soil and the pH value, a thermal and evolved-gas analyzer capable of determining the mineralogy of the soil and detecting ice, microscopes capable of seeing soil particle shapes, sizes and colors at very high resolution, and a soil probe (TECP) capable of detecting unfrozen water in the soil. PHX coincided with an international effort to study the Earth s polar regions named the International Polar Year (IPY; 2007-2008). The best known Earth analog to the Martian high-northern plains, where Phoenix landed, are the McMurdo Dry Valleys (MDV), Antarctica (Fig. 1). Thus, the IPY afforded a unique opportunity to study the MDV with the same foci - history of water and habitability - as PHX. In austral summer 2007, our team took engineering models of WCL and TECP into the MDV and performed analgous measurements. We also collected sterile samples and analyzed them in our home laboratories using state-of-the-art tools. While PHX was not designed to perform biologic analyses, we were able to do so with the MDV analog samples collected.

  20. Phoenix : Complex Adaptive System of Systems (CASoS) engineering version 1.0.

    Moore, Thomas W.; Quach, Tu-Thach; Detry, Richard Joseph; Conrad, Stephen Hamilton; Kelic, Andjelka; Starks, Shirley J.; Beyeler, Walter Eugene; Brodsky, Nancy S.; Verzi, Stephen J.; Brown, Theresa Jean; Glass, Robert John, Jr.; Sunderland, Daniel J.; Mitchell, Michael David; Ames, Arlo Leroy; Maffitt, S. Louise; Finley, Patrick D.; Russell, Eric Dean; Zagonel, Aldo A.; Reedy, Geoffrey E.; Mitchell, Roger A.; Corbet, Thomas Frank, Jr.; Linebarger, John Michael

    2011-08-01

    Complex Adaptive Systems of Systems, or CASoS, are vastly complex ecological, sociological, economic and/or technical systems which we must understand to design a secure future for the nation and the world. Perturbations/disruptions in CASoS have the potential for far-reaching effects due to pervasive interdependencies and attendant vulnerabilities to cascades in associated systems. Phoenix was initiated to address this high-impact problem space as engineers. Our overarching goals are maximizing security, maximizing health, and minimizing risk. We design interventions, or problem solutions, that influence CASoS to achieve specific aspirations. Through application to real-world problems, Phoenix is evolving the principles and discipline of CASoS Engineering while growing a community of practice and the CASoS engineers to populate it. Both grounded in reality and working to extend our understanding and control of that reality, Phoenix is at the same time a solution within a CASoS and a CASoS itself.

  1. Effects of the Phoenix Lander descent thruster plume on the Martian surface

    Plemmons, D. H.; Mehta, M.; Clark, B. C.; Kounaves, S. P.; Peach, L. L.; Renno, N. O.; Tamppari, L.; Young, S. M. M.

    2008-08-01

    The exhaust plume of Phoenix's hydrazine monopropellant pulsed descent thrusters will impact the surface of Mars during its descent and landing phase in the northern polar region. Experimental and computational studies have been performed to characterize the chemical compounds in the thruster exhausts. No undecomposed hydrazine is observed above the instrument detection limit of 0.2%. Forty-five percent ammonia is measured in the exhaust at steady state. Water vapor is observed at a level of 0.25%, consistent with fuel purity analysis results. Moreover, the dynamic interactions of the thruster plumes with the ground have been studied. Large pressure overshoots are produced at the ground during the ramp-up and ramp-down phases of the duty cycle of Phoenix's pulsed engines. These pressure overshoots are superimposed on the 10 Hz quasi-steady ground pressure perturbations with amplitude of about 5 kPa (at touchdown altitude) and have a maximum amplitude of about 20-40 kPa. A theoretical explanation for the physics that causes these pressure perturbations is briefly described in this article. The potential for soil erosion and uplifting at the landing site is also discussed. The objectives of the research described in this article are to provide empirical and theoretical data for the Phoenix Science Team to mitigate any potential problem. The data will also be used to ensure proper interpretation of the results from on-board scientific instrumentation when Martian soil samples are analyzed.

  2. Development of a Ballistic Specification for Magnesium Alloy AZ31B

    Jones, Tyrone L; DeLorme, Richard D

    2008-01-01

    The U.S. Army Research Laboratory (ARL) and Magnesium Elektron North America (MENA) have conducted a joint effort to develop and evaluate rolled plate in commercially available magnesium alloy-temper AZ31B-H24...

  3. Operational Test Report for the 241-AZ-101 Suspended Solids Profiler

    STENKAMP, D.M.

    2000-01-01

    This document comprises the Operational Test Report for the 241-AZ-101 Suspended Solids Profiler. This document presents the results of Operational Testing of the 241-AZ-101 Suspended Solids Profiler (SSP). Testing of the SSP was performed in accordance with OTP-260-005, ''SUSPENDED SOLIDS PROFILER OPERATIONAL TEST PROCEDURE''. The objective of the testing was to verify that all equipment and components functioned as designed, following construction completion and turnover to operations

  4. Microstructure and corrosion resistance of Ce–V conversion coating on AZ31 magnesium alloy

    Jiang, Xiao; Guo, Ruiguang; Jiang, Shuqin

    2015-01-01

    Highlights: • Through simple chemical conversion process, a Ce–V conversion coating is prepared on AZ31 magnesium alloy. The coating (∼2 μm thick) has a duplex structure and is composed of Mg, Al, Ce, V and O in the outer layer and Mg, Al, V, F and O in the inner layer. • The Ce–V conversion coating can increase the E corr by 157 mV and decrease the i corr by 80 times compared to AZ31 magnesium alloy substrate. Moreover, the performance of the Ce–V conversion coating excels the chromate conversion coating on AZ31 magnesium alloy. • The EIS results of Ce–V conversion coating indicate an increase of 10× in the corrosion resistance and a delay in the corrosion process kinetics compared to uncoated AZ31 magnesium alloy in 3.5 wt.% NaCl solution. • The ball cratering is a simple and effective technique of thickness measurement for chemical conversion coating. - Abstract: A Ce–V conversion coating was developed to improve the corrosion resistance of AZ31 magnesium alloy. Scanning electronic microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectrometer (XPS), grazing incidence X-ray diffraction (GIXRD) and the ball cratering test were adopted to study the morphology, chemical composition, structure and thickness of the coating. The coating has duplex structure with network and its thickness is about 2 μm. The coating contains high contents of Ce and V, which exhibits amorphous structure. Potentiodynamic polarization shows the coating can increase the corrosion potential and reduce the corrosion current density of AZ31 magnesium alloy. Moreover, the electrochemical impedance spectra exhibit the coating significantly improves the corrosion resistance of AZ31 magnesium alloy. Results indicate that the Ce–V conversion coating can provide effective protection to AZ31 magnesium alloy

  5. Microstructure and corrosion resistance of Ce–V conversion coating on AZ31 magnesium alloy

    Jiang, Xiao, E-mail: xiaoxiao217@126.com; Guo, Ruiguang; Jiang, Shuqin

    2015-06-30

    Highlights: • Through simple chemical conversion process, a Ce–V conversion coating is prepared on AZ31 magnesium alloy. The coating (∼2 μm thick) has a duplex structure and is composed of Mg, Al, Ce, V and O in the outer layer and Mg, Al, V, F and O in the inner layer. • The Ce–V conversion coating can increase the E{sub corr} by 157 mV and decrease the i{sub corr} by 80 times compared to AZ31 magnesium alloy substrate. Moreover, the performance of the Ce–V conversion coating excels the chromate conversion coating on AZ31 magnesium alloy. • The EIS results of Ce–V conversion coating indicate an increase of 10× in the corrosion resistance and a delay in the corrosion process kinetics compared to uncoated AZ31 magnesium alloy in 3.5 wt.% NaCl solution. • The ball cratering is a simple and effective technique of thickness measurement for chemical conversion coating. - Abstract: A Ce–V conversion coating was developed to improve the corrosion resistance of AZ31 magnesium alloy. Scanning electronic microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectrometer (XPS), grazing incidence X-ray diffraction (GIXRD) and the ball cratering test were adopted to study the morphology, chemical composition, structure and thickness of the coating. The coating has duplex structure with network and its thickness is about 2 μm. The coating contains high contents of Ce and V, which exhibits amorphous structure. Potentiodynamic polarization shows the coating can increase the corrosion potential and reduce the corrosion current density of AZ31 magnesium alloy. Moreover, the electrochemical impedance spectra exhibit the coating significantly improves the corrosion resistance of AZ31 magnesium alloy. Results indicate that the Ce–V conversion coating can provide effective protection to AZ31 magnesium alloy.

  6. Final results of double-shell tank 241-AZ-101 ultrasonic inspection

    JENSEN, C.E.

    1999-01-01

    This document presents the results and documentation of the nondestructive ultrasonic examination of tank 241-AZ-101. A tank inspection supplier was retained to provide and use an ultrasonic examination system (equipment, procedures, and inspectors) to scan a limited area of double-shell tank 241-AZ-101 primary tank wall and welds. The inspection found one reportable indication of thinning and no reportable pitting, corrosion, or cracking

  7. System Description for Tank 241-AZ-101 Waste Retrieval Data Acquisition System

    ROMERO, S.G.

    2000-01-01

    The proposed activity provides the description of the Data Acquisition System for Tank 241-AZ-101. This description is documented in HNF-5572, Tank 241-AZ-101 Waste Retrieval Data Acquisition System (DAS). This activity supports the planned mixer pump tests for Tank 241-AZ-101. Tank 241-AZ-101 has been selected for the first full-scale demonstration of a mixer pump system. The tank currently holds over 960,000 gallons of neutralized current acid waste, including approximately 12.7 inches of settling solids (sludge) at the bottom of the tank. As described in Addendum 4 of the FSAR (LMHC 2000a), two 300 HP mixer pumps with associated measurement and monitoring equipment have been installed in Tank 241-AZ-101. The purpose of the Tank 241-AZ-101 retrieval system Data Acquisition System (DAS) is to provide monitoring and data acquisition of key parameters in order to confirm the effectiveness of the mixer pumps utilized for suspending solids in the tank. The suspension of solids in Tank 241-AZ-101 is necessary for pretreatment of the neutralized current acid waste and eventual disposal as glass via the Hanford Waste Vitrification Plant. HNF-5572 provides a basic description of the Tank 241-AZ-101 retrieval system DAS, including the field instrumentation and application software. The DAS is provided to fulfill requirements for data collection and monitoring. This document is not an operations procedure or is it intended to describe the mixing operation. This USQ screening provides evaluation of HNF-5572 (Revision 1) including the changes as documented on ECN 654001. The changes include (1) add information on historical trending and data backup, (2) modify DAS I/O list in Appendix E to reflect actual conditions in the field, and (3) delete IP address in Appendix F per Lockheed Martin Services, Inc. request

  8. Acceptance Test Report for the 241-AZ-101 Ultrasonic Interface Level Analyzer

    ANDREWS, J.E.

    2000-01-01

    This document comprises the Acceptance Test Report for the 241-AZ-101 Ultrasonic Interface Level Analyzer. This document presents the results of Acceptance Testing of the 241-AZ-101 Ultrasonic Interface Level Analyzers (URSILLAs). Testing of the URSILLAs was performed in accordance with ATP-260-001, ''URSILLA Pre-installation Acceptance Test Procedure''. The objective of the testing was to verify that all equipment and components function in accordance with design specifications and original equipment manufacturer's specifications

  9. Influence of boron addition on the grain refinement and mechanical properties of AZ91 Mg alloy

    Suresh, M.; Srinivasan, A.; Ravi, K.R.; Pillai, U.T.S.; Pai, B.C.

    2009-01-01

    This article reports the effect of boron addition on the grain refinement efficiency and mechanical properties of AZ91 magnesium alloy. The results show that the addition of boron in the form of Al-4B master alloy, significantly refines the grain size of AZ91 alloy. This refinement is due to the presence of AlB 2 particles, which act as potential nucleants for Mg grains. Improved mechanical properties are obtained with the addition of boron due to the finer grains.

  10. Electrochemical corrosion behavior of AZ91D alloy in ethylene glycol

    Fekry, A.M.; Fatayerji, M.Z.

    2009-01-01

    The effect of concentration on the corrosion behavior of Mg-based alloy AZ91D was investigated in ethylene glycol-water solutions using electrochemical techniques i.e. potentiodynamic polarization, electrochemical impedance measurements (EIS) and surface examination via scanning electron microscope (SEM) technique. This can provide a basis for developing new coolants for magnesium alloy engine blocks. Corrosion behavior of AZ91D alloy by coolant is important in the automotive industry. It was found that the corrosion rate of AZ91D alloy decreased with increasing concentration of ethylene glycol. For AZ91D alloy in chloride >0.05 M or fluoride 0.05 M for fluoride containing ethylene glycol solution, some inhibition effect has been observed. The corrosion of AZ91D alloy in the blank can be effectively inhibited by addition of 0.05 mM paracetamol that reacts with AZ91D alloy and forms a protective film on the surface at this concentration as confirmed by surface examination.

  11. Effect of mechanical vibrations on the wear behavior of AZ91 Mg alloy

    Chaturvedi, V.; Pandel, U.; Sharma, A.

    2018-02-01

    AZ91 Mg alloy is the most promising alloy used for structural applications. The vibration induced methods are effective and economic viable in term of mechanical properties. Sliding wear tests were performed on AZ91 Mg alloy using a pin-on- disc configuration. Wear rates were measured at 5 N and 10N at a sliding velocity of 1m/s for varied frequency within the range of 5- 25Hz and a constant amplitude of 2mm. Microstructures of worn surfaces and wear debris were characterized by field emission scanning electron microscopy (FESEM). It is observed that wear resistance of vibrated AZ91 alloy at 15Hz frequency ad 2mm amplitude was superior than cast AZ91 Mg alloy. Finer grain size and equiaxed grain shape both are important parameters for better wear resistance in vibrated AZ91 Mg alloys. FESEM analysis revealed that wear is considerably affected due to frictional heat generated by the relative motion between AZ91 Mg alloy and EN31 steel surface. No single mechanism was responsible for material loss.

  12. Effect of aluminum coatings on corrosion properties of AZ31 magnesium alloy

    Chiu Liuho; Lin Hsingan; Chen Chunchin; Yang Chihfu [Dept. of materials engineering, Tatung Univ., Taipei (Taiwan); Chang Chiahua; Wu Jenchin [Physical chemistry section, chemical systems research div., Chung-Shan Inst. of Science and Technology, Tao-Yuan (Taiwan)

    2003-07-01

    This investigation aimed to increase the corrosion resistance of an AZ31 magnesium alloy by an aluminum arc spray coating and a post-treatment consisted of hot pressing and anodizing. It was found that the aluminum arc spraying alone was incapable of protection against corrosion due to the high amount of pores present in the coating layer. In order to solve the problem, densification of the Al arc-sprayed layer was carried out by hot pressing the coated AZ31 Mg alloy plate under an appropriate range of temperature, time and pressure. After hot pressing the Al coated AZ31 Mg alloy plate exhibited a much improved corrosion resistance. A final anodizing treatment applied to the AZ31 alloy with the dense Al coating further improved its resisting to corrosion. The results showed that, by adopting the Al arc spraying, hot pressing and anodizing process, the corrosion current density of the AZ31 alloy in a 3.5 wt% NaCl solution was from 2.1 x 10{sup -6} A/cm{sup 2} (original AZ31) to 3.7 x 10{sup -7} A/cm{sup 2} (after the surface treatment), which value is close to that of an anodized aluminum plate. (orig.)

  13. Electrochemical corrosion behavior of AZ91D alloy in ethylene glycol

    Fekry, A.M. [Chemistry Department, Faculty of Science, Cairo University, Giza 12613 (Egypt)], E-mail: hham4@hotmail.com; Fatayerji, M.Z. [Chemistry Department, Faculty of Science, Cairo University, Giza 12613 (Egypt)

    2009-11-01

    The effect of concentration on the corrosion behavior of Mg-based alloy AZ91D was investigated in ethylene glycol-water solutions using electrochemical techniques i.e. potentiodynamic polarization, electrochemical impedance measurements (EIS) and surface examination via scanning electron microscope (SEM) technique. This can provide a basis for developing new coolants for magnesium alloy engine blocks. Corrosion behavior of AZ91D alloy by coolant is important in the automotive industry. It was found that the corrosion rate of AZ91D alloy decreased with increasing concentration of ethylene glycol. For AZ91D alloy in chloride >0.05 M or fluoride <0.05 M containing 30% ethylene glycol solution, they are more corrosive than the blank (30% ethylene glycol-70% water). However, at concentrations <0.05 for chloride or >0.05 M for fluoride containing ethylene glycol solution, some inhibition effect has been observed. The corrosion of AZ91D alloy in the blank can be effectively inhibited by addition of 0.05 mM paracetamol that reacts with AZ91D alloy and forms a protective film on the surface at this concentration as confirmed by surface examination.

  14. Effect of rare earth elements on high cycle fatigue behavior of AZ91 alloy

    Mokhtarishirazabad, M.; Boutorabi, S.M.A.; Azadi, M.; Nikravan, M.

    2013-01-01

    This article investigates effects of adding rare earth elements (RE) into a magnesium–aluminum–zinc alloy (the AZ91 alloy) on its high cycle fatigue (HCF) behavior. For this purpose, AZ91 and AZ91+1% RE (AZE911) alloys were gravity casted in a metallic die. RE elements were added to the AZ91 alloy in the form of mischmetals. Microscopic evaluations with the scanning electron microscopy (SEM) and mechanical tests include tensile, hardness and HCF behaviors, were performed on prepared samples. Rotary bending fatigue tests were carried out at a stress ratio (R) of −1 and a frequency of 125 Hz, at the room temperature, in the air. The microscopic investigation demonstrates that the addition of 1% RE elements leads to the formation of Al 11 RE 3 intermetallic particles which is associated to the reduction of β-(Mg 17 Al 12 ) phases. Results of mechanical experiments suggest a negligible effect of adding 1% RE elements on mechanical properties of the AZ91 alloy. Curves of stress-life (S–N) shows an increase in the fatigue strength at 10 5 cycles, from 100±10 MPa to 135±10 MPa, when RE elements were added to the AZ91 alloy

  15. Effect of rare earth elements on high cycle fatigue behavior of AZ91 alloy

    Mokhtarishirazabad, M., E-mail: mehdi-mokhtari@hotmail.com [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Boutorabi, S.M.A. [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Azadi, M.; Nikravan, M. [Irankhodro Powertrain Company (IPCO), Tehran (Iran, Islamic Republic of)

    2013-12-10

    This article investigates effects of adding rare earth elements (RE) into a magnesium–aluminum–zinc alloy (the AZ91 alloy) on its high cycle fatigue (HCF) behavior. For this purpose, AZ91 and AZ91+1% RE (AZE911) alloys were gravity casted in a metallic die. RE elements were added to the AZ91 alloy in the form of mischmetals. Microscopic evaluations with the scanning electron microscopy (SEM) and mechanical tests include tensile, hardness and HCF behaviors, were performed on prepared samples. Rotary bending fatigue tests were carried out at a stress ratio (R) of −1 and a frequency of 125 Hz, at the room temperature, in the air. The microscopic investigation demonstrates that the addition of 1% RE elements leads to the formation of Al{sub 11}RE{sub 3} intermetallic particles which is associated to the reduction of β-(Mg{sub 17}Al{sub 12}) phases. Results of mechanical experiments suggest a negligible effect of adding 1% RE elements on mechanical properties of the AZ91 alloy. Curves of stress-life (S–N) shows an increase in the fatigue strength at 10{sup 5} cycles, from 100±10 MPa to 135±10 MPa, when RE elements were added to the AZ91 alloy.

  16. Soft Costs Fact Sheet

    None

    2016-05-01

    This fact sheet is an overview of the systems integration subprogram at the U.S. Department of Energy SunShot Initiative. Soft costs can vary significantly as a result of a fragmented energy marketplace. In the U.S., there are 18,000 jurisdictions and 3,000 utilities with different rules and regulations for how to go solar. The same solar equipment may vary widely in its final installation price due to process and market variations across jurisdictions, creating barriers to rapid industry growth. SunShot supports the development of innovative solutions that enable communities to build their local economies and establish clean energy initiatives that meet their needs, while at the same time creating sustainable solar market conditions.

  17. Photovoltaics Fact Sheet

    None

    2016-02-01

    This fact sheet is an overview of the Photovoltaics (PV) subprogram at the U.S. Department of Energy SunShot Initiative. The U.S. Department of Energy (DOE)’s Solar Energy Technologies Office works with industry, academia, national laboratories, and other government agencies to advance solar PV, which is the direct conversion of sunlight into electricity by a semiconductor, in support of the goals of the SunShot Initiative. SunShot supports research and development to aggressively advance PV technology by improving efficiency and reliability and lowering manufacturing costs. SunShot’s PV portfolio spans work from early-stage solar cell research through technology commercialization, including work on materials, processes, and device structure and characterization techniques.

  18. Systems Integration Fact Sheet

    None

    2016-06-01

    This fact sheet is an overview of the Systems Integration subprogram at the U.S. Department of Energy SunShot Initiative. The Systems Integration subprogram enables the widespread deployment of safe, reliable, and cost-effective solar energy technologies by addressing the associated technical and non-technical challenges. These include timely and cost-effective interconnection procedures, optimal system planning, accurate prediction of solar resources, monitoring and control of solar power, maintaining grid reliability and stability, and many more. To address the challenges associated with interconnecting and integrating hundreds of gigawatts of solar power onto the electricity grid, the Systems Integration program funds research, development, and demonstration projects in four broad, interrelated focus areas: grid performance and reliability, dispatchability, power electronics, and communications.

  19. Hyperspectral light sheet microscopy

    Jahr, Wiebke; Schmid, Benjamin; Schmied, Christopher; Fahrbach, Florian O.; Huisken, Jan

    2015-09-01

    To study the development and interactions of cells and tissues, multiple fluorescent markers need to be imaged efficiently in a single living organism. Instead of acquiring individual colours sequentially with filters, we created a platform based on line-scanning light sheet microscopy to record the entire spectrum for each pixel in a three-dimensional volume. We evaluated data sets with varying spectral sampling and determined the optimal channel width to be around 5 nm. With the help of these data sets, we show that our setup outperforms filter-based approaches with regard to image quality and discrimination of fluorophores. By spectral unmixing we resolved overlapping fluorophores with up to nanometre resolution and removed autofluorescence in zebrafish and fruit fly embryos.

  20. Characterization of high-strain rate mechanical behavior of AZ31 magnesium alloy using 3D digital image correlation

    Wang, Yanli; Xu, Hanbing; Erdman, Donald L.; Starbuck, Michael J.; Simunovic, Srdjan [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    2011-10-15

    Characterization of the material mechanical behavior at sub-Hopkinson regime (0.1 to 1 000 s{sup -1}) is very challenging due to instrumentation limitations and the complexity of data analysis involved in dynamic loading. In this study, AZ31 magnesium alloy sheet specimens are tested using a custom designed servo-hydraulic machine in tension at nominal strain rates up to 1 000 s{sup -1}. In order to resolve strain measurement artifacts, the specimen displacement is measured using 3D Digital Image correlation instead from actuator motion. The total strain is measured up to {approx} 30%, which is far beyond the measurable range of electric resistance strain gages. Stresses are calculated based on the elastic strains in the tab of a standard dog-bone shaped specimen. Using this technique, the stresses measured for strain rates of 100 s{sup -1} and lower show little or no noise comparing to load cell signals. When the strain rates are higher than 250 s{sup -1}, the noises and oscillations in the stress measurements are significantly decreased from {approx} 250 to 50 MPa. Overall, it is found that there are no significant differences in the elongation, although the material exhibits slight work hardening when the strain rate is increased from 1 to 100 s{sup -1}. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Settlement during vibratory sheet piling

    Meijers, P.

    2007-01-01

    During vibratory sheet piling quite often the soil near the sheet pile wall will settle. In many cases this is not a problem. For situations with houses, pipelines, roads or railroads at relative short distance these settlements may not be acceptable. The purpose of the research described in this

  2. Plasma dynamics in current sheets

    Bogdanov, S.Yu.; Drejden, G.V.; Kirij, N.P.; AN SSSR, Leningrad

    1992-01-01

    Plasma dynamics in successive stages of current sheet evolution is investigated on the base of analysis of time-spatial variations of electron density and electrodynamic force fields. Current sheet formation is realized in a two-dimensional magnetic field with zero line under the action of relatively small initial disturbances (linear regimes). It is established that in the limits of the formed sheet is concentrated dense (N e ∼= 10 16 cm -3 ) (T i ≥ 100 eV, bar-Z i ≥ 2) hot pressure of which is balanced by the magnetic action of electrodynamic forces is carried out both plasma compression in the sheet limits and the acceleration along the sheet surface from a middle to narrow side edges

  3. UBV Photometry at the Outside Eclipse Phase of AZ Cassiopeiae

    Il-Seong Nha

    1994-06-01

    Full Text Available VV Cep-type long period spectroscopic-eclipsing binary AZ Cas has been observed for five years, 1985 Oct ~ 1990 Feb, in UBV at the Ilsan Station of Yonsei University Observatory. A total of 431 observations (U=129, B=142 and V=160 are made for 86 nights. Instrumental differential UBV and B-V light curves made with these observations cover phases nearly a half of one period. There is no appreciable light variation in V but in other two passbands a gradual decrease of the brightness is clearly noticed. The loss of light in B resulted in a reddening in △(B-V by +0.06 at phases between 0.4~0.5 as compared with that of at phase ~0.1. This intrinsic reddening arouses a question why at the orbital phase of the transit of a hot star in front of a cool M supergiant the heating of the facing hemisphere of M supergiant by the strong radiation from the B star is absent. With regard to this unusual situation we propose a hypothesis that a large amount of gas stream of low temperature ejected from the surface of M supergiant component towards the B star dominates the brightness of B star and reflection effect.

  4. CYCLIC FATIGUE RESISTANCE OF AZ91 MAGNESIUM ALLOY

    Aneta Němcová

    2009-11-01

    Full Text Available The paper deals with determination of principal mechanical properties and the investigation of fatigue behaviour of AZ91 magnesium alloy. The experimental material was made by squeeze casting technique and heat treated to obtain T4 state (solution annealing, when hard, brittle Mg17Al12 intermetallic phase is dissolved. The basic mechanical properties (Young’s modulus, ultimate tensile strength, yield strength, elongation to fracture and reduction of area were determined by static tensile test. Furthermore, fatigue parameters were investigated. The S-N curve on the basis of smooth test bars tested under symmetrical push-pull loading at room temperature was evaluated. The measured data were subsequently used for fitting with suitable regression functions (Kohout & Věchet and Stromeyer for determination of the fatigue parameters. Fatigue limit sigma-c of the studied alloy for 108 cycles is approaching 50 MPa. In addition, the fracture surfaces were observed by scanning electron microscopy. The failure analysis proved that the striations were observed in fatigue crack propagation area and in the area of static fracture was observed the transgranular ductile fracture. The structure of the studied alloy in the basic state and after heat treatment was observed by light and scanning electron microscopy.

  5. AzTEC on ASTE Survey of Submillimeter Galaxies

    Kohno, K.; Tamura, Y.; Hatsukade, B.; Nakanishi, K.; Iono, D.; Takata, T.; Wilson, G. W.; Yun, M. S.; Perera, T.; Austermann, J. E.; Scott, K. S.; Hughes, H.; Aretxaga, I.; Tanaka, K.; Oshima, T.; Yamaguchi, N.; Matsuo, H.; Ezawa, H.; Kawabe, R.

    2008-10-01

    We have conducted an unprecedented survey of submillimeter galaxies (SMGs) using the 144 pixel bolometer camera AzTEC mounted on the ASTE 10-m dish in Chile. We have already obtained many (>20) wide (typically 12' × 12' or wider) and deep (1 σ sensitivity of 0.5-1.0 mJy) 1.1 mm continuum images of known blank fields and over-density regions/protoclusters across a wide range of redshifts with a spatial resolution of ˜ 30''. It has resulted in the numerous (˜ a few 100, almost equivalent to the total number of the previously known SMGs) new and secure detections of SMGs. In this paper, we present initial results of two selected fields, SSA 22 and AKARI Deep Field South (ADF-S). A significnat clustering of bright SMGs toward the density peak of LAEs is found in SSA 22. We derived the differential and cumulative number counts from the detected sources in ADF-S, which probe the faintest flux densities (down to ˜1 mJy) among 1-mm blank field surveys to date.

  6. The effects of alloying elements on microstructures and mechanical properties of tungsten inert gas welded AZ80 magnesium alloys joint

    Li, Hui; Zhang, Jiansheng; Ding, Rongrong

    2017-11-01

    The effects of alloying elements on the macrostructures, microstructures and tensile strength of AZ80 Mg alloy weldments were studied in the present study. The results indicate that with the decrease of Al element content of filler wire, the welding defects of seam are gradually eliminated and the β-Mg17Al12 phases at α-Mg boundaries are refined and become discontinuous, which are beneficial to the improvement of tensile strength. With AZ31 Mg alloy filler wire, the maximum tensile strength of AZ80 weldment is 220 MPa and fracture occurs at the welding seam of joint. It is experimentally proved that robust AZ80 Mg alloy joints can be obtained by tungsten inert gas (TIG) welding process with AZ31 Mg alloy filler wire. However, further study is required to improve the microstructures and reduce welding defects of joint in order to further improve the joining strength of AZ80 Mg alloy joint.

  7. Vitamin and Mineral Supplement Fact Sheets

    ... website Submit Search NIH Office of Dietary Supplements Vitamin and Mineral Supplement Fact Sheets Search the list ... Supplements: Background Information Botanical Dietary Supplements: Background Information Vitamin and Mineral Fact Sheets Botanical Supplement Fact Sheets ...

  8. A study on the relationships between corrosion properties and chemistry of thermally oxidised surface films formed on polished commercial magnesium alloys AZ31 and AZ61

    Feliu, Sebastián; Samaniego, Alejandro; Barranco, Violeta; El-Hadad, A.A.; Llorente, Irene; Serra, Carmen; Galván, J.C.

    2014-01-01

    Highlights: • Surface chemistry of heat treated magnesium alloys. • Relation between heat treatment and aluminium subsurface enrichment. • Relation between surface composition and corrosion behaviour. - Abstract: This paper studies the changes in chemical composition of the thin oxide surface films induced by heating in air at 200 °C for time intervals from 5 min to 60 min on the freshly polished commercial AZ31 and AZ61 alloys with a view to better understanding their protective properties. This thermal treatment resulted in the formation of layers enriched in metallic aluminium at the interface between the outer MgO surface films and the bulk material. A strong link was found between the degree of metallic Al enrichment in the subsurface layer (from 10 to 15 at.%) observed by XPS (X-ray photoelectron spectroscopy) in the AZ61 treated samples and the increase in protective properties observed by EIS (electrochemical impedance spectroscopy) in the immersion test in 0.6 M NaCl. Heating for 5–60 min in air at 200 °C seems to be an effective, easy to perform and inexpensive method for increasing the corrosion resistance of the AZ61 alloy by approximately two or three times

  9. A study on the relationships between corrosion properties and chemistry of thermally oxidised surface films formed on polished commercial magnesium alloys AZ31 and AZ61

    Feliu, Sebastián, E-mail: sfeliu@cenim.csic.es [Centro Nacional de Investigaciones Metalúrgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Samaniego, Alejandro [Centro Nacional de Investigaciones Metalúrgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Barranco, Violeta [Instituto de Ciencias de Materiales de Madrid, ICMM, Consejo Superior de Investigaciones Científicas, CSIC, Sor Juana Inés de la Cruz, 3, Cantoblanco, 28049, Madrid (Spain); El-Hadad, A.A. [Physics Department, Faculty of Science, Al-Azhar University, Nasr City 11884, Cairo (Egypt); Llorente, Irene [Centro Nacional de Investigaciones Metalúrgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Serra, Carmen [Servicio de Nanotecnologia y Análisis de Superficies, CACTI, Universidade de Vigo, 36310 Vigo (Spain); Galván, J.C. [Centro Nacional de Investigaciones Metalúrgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain)

    2014-03-01

    Highlights: • Surface chemistry of heat treated magnesium alloys. • Relation between heat treatment and aluminium subsurface enrichment. • Relation between surface composition and corrosion behaviour. - Abstract: This paper studies the changes in chemical composition of the thin oxide surface films induced by heating in air at 200 °C for time intervals from 5 min to 60 min on the freshly polished commercial AZ31 and AZ61 alloys with a view to better understanding their protective properties. This thermal treatment resulted in the formation of layers enriched in metallic aluminium at the interface between the outer MgO surface films and the bulk material. A strong link was found between the degree of metallic Al enrichment in the subsurface layer (from 10 to 15 at.%) observed by XPS (X-ray photoelectron spectroscopy) in the AZ61 treated samples and the increase in protective properties observed by EIS (electrochemical impedance spectroscopy) in the immersion test in 0.6 M NaCl. Heating for 5–60 min in air at 200 °C seems to be an effective, easy to perform and inexpensive method for increasing the corrosion resistance of the AZ61 alloy by approximately two or three times.

  10. A study on the relationships between corrosion properties and chemistry of thermally oxidised surface films formed on polished commercial magnesium alloys AZ31 and AZ61

    Feliu, Sebastián; Samaniego, Alejandro; Barranco, Violeta; El-Hadad, A. A.; Llorente, Irene; Serra, Carmen; Galván, J. C.

    2014-03-01

    This paper studies the changes in chemical composition of the thin oxide surface films induced by heating in air at 200 °C for time intervals from 5 min to 60 min on the freshly polished commercial AZ31 and AZ61 alloys with a view to better understanding their protective properties. This thermal treatment resulted in the formation of layers enriched in metallic aluminium at the interface between the outer MgO surface films and the bulk material. A strong link was found between the degree of metallic Al enrichment in the subsurface layer (from 10 to 15 at.%) observed by XPS (X-ray photoelectron spectroscopy) in the AZ61 treated samples and the increase in protective properties observed by EIS (electrochemical impedance spectroscopy) in the immersion test in 0.6 M NaCl. Heating for 5-60 min in air at 200 °C seems to be an effective, easy to perform and inexpensive method for increasing the corrosion resistance of the AZ61 alloy by approximately two or three times.

  11. Study on fused/cast AZS refractories for deployment in vitrification of radioactive waste effluents

    Sengupta, Pranesh, E-mail: praneshsengupta@gmail.com [Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Mishra, R.K.; Soudamini, N. [Waste Management Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Sen, D.; Mazumder, S. [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Kaushik, C.P. [Waste Management Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Ajithkumar, T.G. [Central NMR Facility, National Chemical Laboratory, Pune 411 008 (India); Banerjee, K. [Nuclear Recycle Group, Mumbai 400 085 (India)

    2015-12-15

    ‘Fused/cast Al{sub 2}O{sub 3}–ZrO{sub 2}–SiO{sub 2} (FC-AZS)’ is being considered as ‘glass contact refractory’ within ceramic melters, to be used for nuclear waste immobilization. Microstructural analyses reveal random distributions of baddeleyite (ZrO{sub 2}) within aluminosilicate (Al{sub 2}SiO{sub 5}) matrix. {sup 27}Al and {sup 29}Si NMR data suggest that within aluminosilicate matrix Al occurs in both 4- and 6-fold co-ordinations whereas Si prefers a 4-fold environment. Polydispersity of pores has been studied with small-angle neutron scattering (SANS) technique. Corrosion rates of FC-AZS within 6 M HNO{sub 3}, simulated wastes (500 h exposure), and borosilicate melt (975 °C, 800 h exposure) are found to be 0.38 × 10{sup 3} μmy{sup −1}, 0.13 × 10{sup 3} μmy{sup −1} and 4.75 × 10{sup 3} μmy{sup −1} respectively. A comparison of chemical interaction data clearly suggests that FC-AZS exhibits better chemical durability than AZC refractory (Al{sub 2}O{sub 3}–ZrO{sub 2}–Cr{sub 2}O{sub 3}, also used for similar purpose). Thermal cycling studies indicate that FC-AZS retains structural integrity (including compressive strength and density) even up to 20 cycles. - Highlights: • Vitrification of nuclear waste using AZS refractory within ceramic melter. • Microstructure of AZS refractory. • Interaction of AZS with simulated high level waste and glass.

  12. Rapid coating of AZ31 magnesium alloy with calcium deficient hydroxyapatite using microwave energy

    Ren, Yufu; Zhou, Huan; Nabiyouni, Maryam; Bhaduri, Sarit B.

    2015-01-01

    Due to their unique biodegradability, magnesium alloys have been recognized as suitable metallic implant materials for degradable bone implants and bioresorbable cardiovascular stents. However, the extremely high degradation rate of magnesium alloys in physiological environment has restricted its practical application. This paper reports the use of a novel microwave assisted coating technology to improve the in vitro corrosion resistance and biocompatibility of Mg alloy AZ31. Results indicate that a dense calcium deficient hydroxyapatite (CDHA) layer was uniformly coated on a AZ31 substrate in less than 10 min. Weight loss measurement and SEM were used to evaluate corrosion behaviors in vitro of coated samples and of non-coated samples. It was seen that CDHA coatings remarkably reduced the mass loss of AZ31 alloy after 7 days of immersion in SBF. In addition, the prompt precipitation of bone-like apatite layer on the sample surface during immersion demonstrated a good bioactivity of the CDHA coatings. Proliferation of osteoblast cells was promoted in 5 days of incubation, which indicated that the CDHA coatings could improve the cytocompatibility of the AZ31 alloy. All the results suggest that the CDHA coatings, serving as a protective layer, can enhance the corrosion resistance and biological response of magnesium alloys. Furthermore, this microwave assisted coating technology could be a promising method for rapid surface modification of biomedical materials. - Highlights: • A microwave assisted coating process for biodegradable Mg alloy. • CDHA coatings were successfully developed on AZ31 alloy in minutes. • The as-deposited CDHA coatings significantly reduced the degradation rate of AZ31 alloy. • The CDHA coated AZ31 alloy showed good bioactivity and biocompatibility in vitro. • The microwave assisted coating process can be used as rapid surface modification for bioimplants

  13. Rapid coating of AZ31 magnesium alloy with calcium deficient hydroxyapatite using microwave energy

    Ren, Yufu, E-mail: Yufu.Ren@rockets.utoledo.edu [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Zhou, Huan [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Institute of Biomedical Engineering and Health Sciences, Changzhou University, Changzhou, Jiangsu (China); Nabiyouni, Maryam [Department of Bioengineering, The University of Toledo, Toledo, OH (United States); Bhaduri, Sarit B. [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Division of Dentistry, The University of Toledo, Toledo, OH (United States)

    2015-04-01

    Due to their unique biodegradability, magnesium alloys have been recognized as suitable metallic implant materials for degradable bone implants and bioresorbable cardiovascular stents. However, the extremely high degradation rate of magnesium alloys in physiological environment has restricted its practical application. This paper reports the use of a novel microwave assisted coating technology to improve the in vitro corrosion resistance and biocompatibility of Mg alloy AZ31. Results indicate that a dense calcium deficient hydroxyapatite (CDHA) layer was uniformly coated on a AZ31 substrate in less than 10 min. Weight loss measurement and SEM were used to evaluate corrosion behaviors in vitro of coated samples and of non-coated samples. It was seen that CDHA coatings remarkably reduced the mass loss of AZ31 alloy after 7 days of immersion in SBF. In addition, the prompt precipitation of bone-like apatite layer on the sample surface during immersion demonstrated a good bioactivity of the CDHA coatings. Proliferation of osteoblast cells was promoted in 5 days of incubation, which indicated that the CDHA coatings could improve the cytocompatibility of the AZ31 alloy. All the results suggest that the CDHA coatings, serving as a protective layer, can enhance the corrosion resistance and biological response of magnesium alloys. Furthermore, this microwave assisted coating technology could be a promising method for rapid surface modification of biomedical materials. - Highlights: • A microwave assisted coating process for biodegradable Mg alloy. • CDHA coatings were successfully developed on AZ31 alloy in minutes. • The as-deposited CDHA coatings significantly reduced the degradation rate of AZ31 alloy. • The CDHA coated AZ31 alloy showed good bioactivity and biocompatibility in vitro. • The microwave assisted coating process can be used as rapid surface modification for bioimplants.

  14. Microscopy analysis of soils at the Phoenix landing site, Mars : Classification of soil particles and description of their optical and magnetic properties

    Goetz, W.; Pike, W.T.; Hviid, S.F.; Madsen, M.B.; Morris, R.V.; Hecht, M.H.; Staufer, U.; Leer, K.; Sykulska, H.; Hemmig, E.; Marshall, J.; Morookian, J.M.; Parrat, D.; Vijendran, S.; Bos, B.J.; El Maarry, M.R.; Keller, H.U.; Kramm, R.; Markiewicz, W.J.; Drube, L.; Blaney, D.; Arvidson, R.E.; Bell, J.F.; Reynolds, R.; Smith, P.H.; Woida, P.; Woida, R.; Tanner, R.

    2010-01-01

    The optical microscope onboard the Phoenix spacecraft has returned color images (4 ?m pixel?1) of soils that were delivered to and held on various substrates. A preliminary taxonomy of Phoenix soil particles, based on color, size, and shape, identifies the following particle types [generic names in

  15. Selectively reflective transparent sheets

    Waché, Rémi; Florescu, Marian; Sweeney, Stephen J.; Clowes, Steven K.

    2015-08-01

    We investigate the possibility to selectively reflect certain wavelengths while maintaining the optical properties on other spectral ranges. This is of particular interest for transparent materials, which for specific applications may require high reflectivity at pre-determined frequencies. Although there exist currently techniques such as coatings to produce selective reflection, this work focuses on new approaches for mass production of polyethylene sheets which incorporate either additives or surface patterning for selective reflection between 8 to 13 μ m. Typical additives used to produce a greenhouse effect in plastics include particles such as clays, silica or hydroxide materials. However, the absorption of thermal radiation is less efficient than the decrease of emissivity as it can be compared with the inclusion of Lambertian materials. Photonic band gap engineering by the periodic structuring of metamaterials is known in nature for producing the vivid bright colors in certain organisms via strong wavelength-selective reflection. Research to artificially engineer such structures has mainly focused on wavelengths in the visible and near infrared. However few studies to date have been carried out to investigate the properties of metastructures in the mid infrared range even though the patterning of microstructure is easier to achieve. We present preliminary results on the diffuse reflectivity using FDTD simulations and analyze the technical feasibility of these approaches.

  16. Effect of the chemistry and structure of the native oxide surface film on the corrosion properties of commercial AZ31 and AZ61 alloys

    Feliu, Sebastian, E-mail: sfeliu@cenim.csic.es [Centro Nacional de Investigaciones Metalurgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Maffiotte, C. [CIEMAT-DT edificio 30, Avda. Complutense, 22, 28040 Madrid (Spain); Samaniego, A.; Galvan, Juan Carlos [Centro Nacional de Investigaciones Metalurgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Barranco, Violeta [Centro Nacional de Investigaciones Metalurgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Instituto de Ciencias de Materiales de Madrid, ICMM, Consejo Superior de Investigaciones Cientificas, CSIC, Sor Juana Ines de la Cruz, 3, Cantoblanco, 28049, Madrid (Spain)

    2011-08-01

    The purpose of this study has been to advance in knowledge of the chemical composition, structure and thickness of the thin native oxide film formed spontaneously in contact with the laboratory atmosphere on the surface of freshly polished commercial AZ31 and AZ61 alloys with a view to furthering the understanding of protection mechanisms. For comparative purposes, and to more fully describe the behaviour of the native oxide film, the external oxide films formed as a result of the manufacturing process (as-received condition) have been characterised. The technique applied in this research to study the thin oxide films (thickness of just a few nanometres) present on the surface of the alloys has basically been XPS (X-ray photoelectron spectroscopy) in combination with ion sputtering. Corrosion properties of the alloys were studied in 0.6 M NaCl by measuring charge transfer resistance values, which are deduced from EIS (electrochemical impedance spectroscopy) measurements after 1 h of exposure. Alloy AZ61 generally showed better corrosion resistance than AZ31, and the freshly polished alloys showed better corrosion resistance than the alloys in as-received condition. This is attributed to a combination of (1) higher thickness of the native oxide film on the AZ61 alloy and (2) greater uniformity of the oxide film in the polished condition. The formation of an additional oxide layer composed by a mixture of spinel (MgAl{sub 2}O{sub 4}) and MgO seems to diminish the protective properties of the passive layer on the surface of the alloys in as-received condition.

  17. Effect of the chemistry and structure of the native oxide surface film on the corrosion properties of commercial AZ31 and AZ61 alloys

    Feliu, Sebastian; Maffiotte, C.; Samaniego, A.; Galvan, Juan Carlos; Barranco, Violeta

    2011-01-01

    The purpose of this study has been to advance in knowledge of the chemical composition, structure and thickness of the thin native oxide film formed spontaneously in contact with the laboratory atmosphere on the surface of freshly polished commercial AZ31 and AZ61 alloys with a view to furthering the understanding of protection mechanisms. For comparative purposes, and to more fully describe the behaviour of the native oxide film, the external oxide films formed as a result of the manufacturing process (as-received condition) have been characterised. The technique applied in this research to study the thin oxide films (thickness of just a few nanometres) present on the surface of the alloys has basically been XPS (X-ray photoelectron spectroscopy) in combination with ion sputtering. Corrosion properties of the alloys were studied in 0.6 M NaCl by measuring charge transfer resistance values, which are deduced from EIS (electrochemical impedance spectroscopy) measurements after 1 h of exposure. Alloy AZ61 generally showed better corrosion resistance than AZ31, and the freshly polished alloys showed better corrosion resistance than the alloys in as-received condition. This is attributed to a combination of (1) higher thickness of the native oxide film on the AZ61 alloy and (2) greater uniformity of the oxide film in the polished condition. The formation of an additional oxide layer composed by a mixture of spinel (MgAl 2 O 4 ) and MgO seems to diminish the protective properties of the passive layer on the surface of the alloys in as-received condition.

  18. Superfund fact sheet: The remedial program. Fact sheet

    1992-09-01

    The fact sheet describes what various actions the EPA can take to clean up hazardous wastes sites. Explanations of how the criteria for environmental and public health risk assessment are determined and the role of state and local governments in site remediation are given. The fact sheet is one in a series providing reference information about Superfund issues and is intended for readers with no formal scientific training

  19. Survey of intestinal parasitism in dogs in the Phoenix metropolitan area.

    Cornell, Heather N; O'Neal, Peter R; Wong, Valerie M; Noah, Donald L

    2017-09-01

    OBJECTIVE To determine the prevalence of selected intestinal parasites in pet dogs and recently apprehended free-roaming (AFR) shelter dogs in the Phoenix metropolitan area and compare those prevalences between the 2 groups. DESIGN Cross-sectional study. SAMPLE Convenience samples of fecal specimens from owned pet dogs from the Phoenix metropolitan area (n = 175) and free-roaming dogs apprehended and admitted to Maricopa County Animal Care and Control and Arizona Humane Society facilities from November 2014 through March 2015 (188). PROCEDURES Fresh fecal specimens were collected from all dogs; for AFR shelter dogs, specimens were collected within 72 hours after facility admission. Standard centrifugal flotation tests and an ELISA were performed to detect 5 common intestinal parasites (roundworms, hookworms, whipworms, Giardia spp, and Cystoisospora spp). Group comparisons were performed by means of the χ 2 test and Rogan-Gladen prevalence estimate. RESULTS At least 1 of the 5 evaluated parasites was detected in 85 (45.2%) fecal specimens from AFR shelter dogs and 24 (13.7%) specimens from owned pet dogs. This prevalence differed significantly between the groups. Notably, the prevalence of Giardia spp in AFR shelter dogs (n = 76 [40.4%]) was higher than previously reported in the United States. CONCLUSIONS AND CLINICAL RELEVANCE The prevalence of the evaluated intestinal parasites, particularly of Giardia spp, in AFR shelter dogs was higher than expected. This information is important for veterinarians, animal shelter personnel, pet owners, human health-care providers, and public health officials to consider when devising effective interventions and risk communication efforts against potential zoonotic threats, particularly those relevant to the Phoenix metropolitan area.

  20. Fatigue life of the casting-magnesium alloy AZ91

    Eisenmeier, G.; Mughrabi, H.; Holzwarth, B.; Hoeppel, H.W.; Ding, H.Z.

    2000-01-01

    The cyclic deformation behaviour of the die-casting magnesium alloy AZ91 was investigated at constant total strain amplitudes between 1.4 x 10 -3 and 2 x 10 -2 at room temperature (20 C) and at 130 C. At low total strain amplitudes, a weak cyclic softening at the beginning of the fatigue tests is followed by cyclic hardening, whereas at high total strain amplitudes a strong cyclic hardening occurs throughout. The fatigue lives at 130 C are slightly longer at high strain amplitudes but shorter at low strain amplitudes than at room temperature. The fatigue life data for both temperatures can be described well by the laws of Manson-Coffin and Basquin. The microstructural investigations performed show the strong influence of several microstructural features on the initiation and propagation of fatigue cracks. In order to understand the fatigue crack propagation behaviour, fatigue tests were interrupted at certain numbers of cycles in order to make replicas of the surface of the samples. It could be verified that crack propagation occurs mainly by the coalescence of smaller cracks. Furthermore, unloading tests, performed within a closed cycle, were carried out in order to capture the changes of stiffness (compliance) during a closed cycle with the aim to ascertain the damage evolution occurring during the fatigue tests and to determine the stresses at which the cracks open and close. Finally, two-step fatigue tests were carried out with the objective to quantify deviations from the linear damage rule (LDR) of Palmgren and Miner. The results obtained in this study will be used to formulate a microstructurally based life-prediction concept for single-step as well as for two-step fatigue loading. (orig.)

  1. Dose rate analysis for Tank 101 AZ (Project W151)

    Schwarz, R.A.; Hillesland, K.E.; Carter, L.L.

    1994-11-01

    This document describes the expected dose rates for modification to tank 101 AZ including modifications to the steam coil, mixer pump, and temperature probes. The thrust of the effort is to determine dose rates from: modification of a steam coil and caisson; the installation of mixer pumps; the installation of temperature probes; and estimates of dose rates that will be encountered while making these changes. Because the dose rates for all of these configurations depend upon the photon source within the supernate and sludge, comparisons were also made between measured dose rates within a drywell and the corresponding calculated dose rates. The calculational tool used is a Monte Carlo (MCNP 2 ) code since complicated three dimensional geometries are involved. A summary of the most important results of the entire study is given in Section 2. The basic calculational geometry model of the tank is discussed in Section 3, along with a tabulation of the photon sources that were used within the supernate and the sludge, and a discussion of uncertainties. The calculated dose rates around the steam coil and caisson before and after modification are discussed in Section 4. The configuration for the installation of the mixer pumps and the resulting dose rates are given in Section 5. The predicted changes in dose rates due to a possible dilution of the supernate source are given in Section 6. The calculational configuration used to model the installation of temperature probes and the resulting predicted dose rates are discussed in Section 7. Finally, comparisons of measured to calculated dose rates within a drywell are summarized in Section 8. Extended discussions of calculational models and Monte Carlo optimization techniques used are included in Appendix A

  2. The applicability of ALPHA/PHOENIX/ANC nuclear design code system on Korean standard PWR's

    Lee, Kookjong; Choi, Kie-Yong; Lee, Hae-Chan; Roh, Eun-Rae

    1996-01-01

    For the Korean Standard Nuclear Power Plant (KSNPP) designed based on Combustion Engineering (CE) System 80, the Westinghouse nuclear design code system ALPHA/PHOENIX/ANC was applied to the follow-up design of initial and reload core of KSNPP. The follow-up design results of Yonggwang Unit 3 Cycle 1, 2 and Yonggwang Unit 4 Cycle 1 have shown good agreements with the measured data. The assemblywise power distributions have shown less than 2% average differences and critical boron concentrations have shown less than 20 ppm differences. All the low power physics test parameters are in good agreement. Consequently, APA design code system can be applied to KNSPP cores. (author)

  3. Debris flows from small catchments of the Ma Ha Tuak Range, metropolitan Phoenix, Arizona

    Dorn, Ronald I.

    2010-08-01

    Debris flows debauch from tiny but steep mountain catchments throughout metropolitan Phoenix, Arizona, USA. Urban growth in the past half-decade has led to home construction directly underneath hundreds of debris-flow channels, but debris flows are not recognized as a potential hazard at present. One of the first steps in a hazard assessment is to determine occurrence rates. The north flank of the Ma Ha Tuak Range, just 10 km from downtown Phoenix, was selected to determine the feasibility of using the varnish microlaminations (VML) method to date every debris-flow levee from 127 catchment areas. Only 152 of the 780 debris-flow levees yielded VML ages in a first round of sampling; this high failure rate is due to erosion of VML by microcolonial fungi. The temporal pattern of preserved debris-flow levees indicates anomalously high production of debris flows at about 8.1 ka and about 2.8 ka, corresponding to Northern Hemisphere climatic anomalies. Because many prior debris flows are obliterated by newer events, the minimum overall occurrence rates of 1.3 debris flows per century for the last 60 ka, 2.2 flows/century for the latest Pleistocene, and 5 flows/century for the last 8.1 ka has little meaning in assessment of a contemporary hazard. This is because newer debris flows have obliterated an unknown number of past deposits. More meaningful to a hazards analysis is the estimate that 56 flows have occurred in the last 100 years on the north side of the range, an estimate that is consistent with direct observations of three small debris flows resulting events from a January 18-22, 2010 storm producing 70 mm of precipitation in the Ma Ha Tuak Range, and a 500 m long debris flow in a northern metropolitan Phoenix location that received over 150 mm of precipitation in this same storm. These findings support the need for a more extensive hazard assessment of debris flows in metropolitan Phoenix.

  4. Analysis of Phoenix Anomalies and IV and V Findings Applied to the GRAIL Mission

    Larson, Steve

    2012-01-01

    Analysis of patterns in IV&V findings and their correlation with post-launch anomalies allowed GRAIL to make more efficient use of IV&V services . Fewer issues. . Higher fix rate. . Better communication. . Increased volume of potential issues vetted, at lower cost. . Hard to make predictions of post-launch performance based on IV&V findings . Phoenix made sound fix/use as-is decisions . Things that were fixed eliminated some problems, but hard to quantify. . Broad predictive success in one area, but inverse relationship in others.

  5. Controlling microstructure and texture in magnesium alloy sheet by shear-based deformation processing

    Sagapuram, Dinakar

    Application of lightweight Mg sheet is limited by its low workability, both in production of sheet (typically by multistep hot and cold-rolling) and forming of sheet into components. Large strain extrusion machining (LSEM), a constrained chip formation process, is used to create Mg alloy AZ31B sheet in a single deformation step. The deformation in LSEM is shown to be intense simple shear that is confined to a narrow zone, which results in significant deformation-induced heating up to ~ 200°C and reduces the need for pre-heating to realize continuous sheet forms. This study focuses on the texture and microstructure development in the sheet processed by LSEM. Interestingly, deep, highly twinned steady-state layer develops in the workpiece subsurface due to the compressive field ahead of the shear zone. The shear deformation, in conjunction with this pre-deformed twinned layer, results in tilted-basal textures in the sheet with basal planes tilted well away from the surface. These textures are significantly different from those in rolled sheet, where basal planes are nearly parallel to the surface. By controlling the strain path, the basal plane inclination from the surface could be varied in the range of 32-53°. B-fiber (basal plane parallel to LSEM shear plane), associated with basal slip, is the major texture component in the sheet. An additional minor C2-fiber component appears above 250°C due to the thermal activation of pyramidal slip. Together with these textures, microstructure ranges from severely cold-worked to (dynamically) recrystallized type, with the corresponding grain sizes varying from ultrafine- (~ 200 nm) to fine- (2 mum) grained. Small-scale limiting dome height (LDH) confirmed enhanced formability (~ 50% increase in LDH) of LSEM sheet over the conventional rolled sheet. Premature, twinning-driven shear fractures are observed in the rolled sheet with the basal texture. In contrast, LSEM sheet with a tilted-basal texture favorably oriented for

  6. Influence of cerium on passivity behavior of wrought AZ91 alloy

    Wang Henan; Li Ying; Wang Fuhui

    2008-01-01

    In this paper, more focus had been put on the passivity behavior of wrought AZ91 alloy with 1.5 mass% Ce. The passive current density of wrought AZ91 alloy increased with addition of Ce and the passive film became unstable. Structures and compositions of the passive films formed on wrought AZ91 alloy without and with Ce in 0.01 M NaOH aqueous solution were analyzed by potentiostatic polarization, potentiostatic-galvanostatic (P-G) transient technique and X-ray photoelectron spectroscopy (XPS). The results showed that Ce only accumulated in the inner layer of passive film in the form of CeO 2 . Further analysis revealed that there were two main effects of Ce on the passive process of wrought AZ91 alloy: first, the existence of CeO 2 in inner layer of passive film made mass transport through the passive film follow tangent hyperbolic (T) impedance instead of Warburg impedance (W); second, donor concentration (N d ) of the passive film increased by a factor 10 when 1.5 mass% Ce existed in wrought AZ91 alloy, which led to the higher passivity current density

  7. 2012 Swimming Season Fact Sheets

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  8. State Fact Sheets on COPD

    ... Submit Search The CDC Chronic Obstructive Pulmonary Disease (COPD) Note: Javascript is disabled or is not supported ... message, please visit this page: About CDC.gov . COPD Homepage Data and Statistics Fact Sheets Publications Publications ...

  9. Framing the Tenth Anniversary of 9/11:  A Comparison of CNN and Phoenix TV commemorative websites

    Zhuang, Yuxi

    2013-01-01

    It has been more than ten years since the 9/11 attacks in 2001, but the events related to the attacks are still a focus for the whole world. This study examined the news coverage of the 9/11 tenth anniversary from Phoenix TV and CNN, which are among the most influential news media in China and the U.S., respectively. A systematic content analysis was performed using latest news, opinion articles, photographs, and videos as classified by CNN and Phoenix TV on their commemorative 9/11 tenth ann...

  10. Australian Government Balance Sheet Management

    Wilson Au-Yeung; Jason McDonald; Amanda Sayegh

    2006-01-01

    Since almost eliminating net debt, the Australian Government%u2019s attention has turned to the financing of broader balance sheet liabilities, such as public sector superannuation. Australia will be developing a significant financial asset portfolio in the %u2018Future Fund%u2019 to smooth the financing of expenses through time. This raises the significant policy question of how best to manage the government balance sheet to reduce risk. This paper provides a framework for optimal balance sh...

  11. Energy information sheets, July 1998

    NONE

    1998-07-01

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

  12. Energy information sheets, September 1996

    NONE

    1996-09-01

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

  13. Detection of defects in laser welding of AZ31B magnesium alloy in zero-gap lap joint configuration by a real-time spectroscopic analysis

    Harooni, Masoud; Carlson, Blair; Kovacevic, Radovan

    2014-05-01

    The effect of surface oxide layer existing at the lap-joint faying surface of magnesium sheets is investigated on the keyhole dynamics of the weld pool and weld bead qualities. It is observed that by removing the oxide layer from the faying surface of the lap joint, a high quality weld can be achieved in the laser welding process. However, the presence of an oxide layer deteriorates the quality of the weld by forming pores at the interface of the two overlapped sheets. The purpose of this paper is to identify the correlation between the integrity of the weld and the interaction between the laser and material. A spectroscopy sensor was applied to detect the spectra emitted from a plasma plume during the laser welding of AZ31B magnesium alloy in a zero-gap lap joint configuration. The electron temperature was calculated by applying a Boltzmann plot method based on the detected spectra, and the correlation between the pore formation and the spectral signals was studied. The laser molten pool and the keyhole condition were monitored in real-time by a high speed charge-coupled device (CCD) camera. A green laser was used as an illumination source in order to detect the influence of the oxide layer on the dynamic behavior of the molten pool. Results revealed that the detected spectrum and weld defects had a meaningful correlation for real-time monitoring of the weld quality during laser welding of magnesium alloys.

  14. Korozní odolnost tvářených hořčíkových slitin AZ31 a AZ61 v Hankovì roztoku

    Tkacz, J.; Slouková, K.; Minda, J.; Drábiková, J.; Fintová, Stanislava; Doležal, P.; Wasserbauer, J.

    2016-01-01

    Roč. 60, č. 4 (2016), s. 101-106 ISSN 1804-1213 Institutional support: RVO:68081723 Keywords : corrosion * AZ31 magnesium alloy * AZ61 magnesium alloy Subject RIV: JK - Corrosion ; Surface Treatment of Materials https://www.degruyter.com/view/j/kom.2016.60.issue-4/kom-2016-0016/kom-2016-0016.xml?format=INT

  15. FDTD modeling of thin impedance sheets

    Luebbers, Raymond J.; Kunz, Karl S.

    1991-01-01

    Thin sheets of resistive or dielectric material are commonly encountered in radar cross section calculations. Analysis of such sheets is simplified by using sheet impedances. In this paper it is shown that sheet impedances can be modeled easily and accurately using Finite Difference Time Domain (FDTD) methods.

  16. Microstructures of friction welded joints of AZ31 to AM60 magnesium alloys

    Fukumoto, S.; Ono, T.; Tanaka, S.; Tsubakino, H. [Graduate School of Engineering, Himeji Inst. of Tech., Hyogo (Japan); Tomita, T.; Aritoshi, M. [Hyogo Prefectural Inst. of Industrial Research, Kobe, Hyogo (Japan); Okita, K. [Inst. of Industrial Research, Osaka Sangyo Univ., Osaka (Japan)

    2003-07-01

    AZ31 magnesium alloy was friction-welded to AM60 and the microstructures and the friction welding process were studied. The microstructures changed near the weld interface. The AZ31 was refined to a grain size of several {mu}m near the weld interface. The nucleation occurred in the shear bands that were introduced during the welding process. On the other hand, the eutectic structure was deformed and the lamellar structure which was composed of {alpha}-Mg and Mg{sub 17}Al{sub 12} was formed near the weld interface in AM60 alloy. In the friction process, the adhesion and peel off occurred alternately between AZ31 and AM60. Eventually, bonding was completed during upset process. (orig.)

  17. Diffusion Bonding and Post-Weld Heat Treatment of Extruded AZ91 Magnesium Alloys

    Fei LIN

    2015-11-01

    Full Text Available The grain size of as-extruded AZ91 magnesium alloys was refined to 12.31 μm from 21.41 μm by recrystallization annealing. The vacuum diffusion welding of as-annealed AZ91 magnesium alloys was researched. The results showed that the maximum shear strength of joints reached 64.70 MPa in the situation of 10 MPa bonding pressure, 18 Pa vacuum degree, 470 °C bonding temperature and 90 min bonding time; both bonding temperature and time are the main influence factors on as-extruded AZ91 magnesium alloys diffusion welding. Then the diffusion welded specimens were annealed, and the shear strength of joints was further improved to 76.93 MPa.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9699

  18. Biodegradable behaviors of AZ31 magnesium alloy in simulated body fluid

    Song Yingwei; Shan Dayong; Chen Rongshi; Zhang Fan; Han Enhou

    2009-01-01

    Magnesium alloys have unique advantages to act as biodegradable implants for clinical application. The biodegradable behaviors of AZ31 in simulated body fluid (SBF) for various immersion time intervals were investigated by electrochemical impedance spectroscopy (EIS) tests and scanning electron microscope (SEM) observation, and then the biodegradable mechanisms were discussed. It was found that a protective film layer was formed on the surface of AZ31 in SBF. With increasing of immersion time, the film layer became more compact. If the immersion time was more than 24 h, the film layer began to degenerate and emerge corrosion pits. In the meantime, there was hydroxyapatite particles deposited on the film layer. The hydroxyapatite is the essential component of human bone, which indicates the perfect biocompatibility of AZ31 magnesium alloy.

  19. Tank 241-AZ-102 Privatization Push Mode Core Sampling and Analysis Plan; FINAL

    TEMPLETON, A.M.

    1999-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for samples obtained from tank 241-AZ-102. The purpose of this sampling event is to obtain information about the characteristics of the contents of 241-AZ-102. Push mode core samples will be obtained from risers 15C and 24A to provide sufficient material for the chemical analyses and tests required to satisfy these data quality objectives. The 222-S Laboratory will extrude core samples, composite the liquids and solids, perform chemical analyses, and provide subsamples to the Process Chemistry Laboratory. The Process Chemistry Laboratory will prepare test plans and perform process tests to evaluate the behavior of the 241-AZ-102 waste undergoing the retrieval and treatment scenarios defined in the applicable DQOs. Requirements for analyses of samples originating in the process tests will be documented in the corresponding test plan

  20. Tank 241-AZ-101 Mixer Pump Test Vapor Sampling and Analysis Plan

    TEMPLETON, A.M.

    2000-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for vapor samples obtained during the operation of mixer pumps in tank 241-AZ-101. The primary purpose of the mixer pump test (MPT) is to demonstrate that the two 300 horsepower mixer pumps installed in tank 241-AZ-101 can mobilize the settled sludge so that it can be retrieved for treatment and vitrification. Sampling will be performed in accordance with Tank 241-AZ-101 Mixer Pump Test Data Quality Objective (Banning 1999) and Data Quality Objectives for Regulatory Requirements for Hazardous and Radioactive Air Emissions Sampling and Analysis (Mulkey 1999). The sampling will verify if current air emission estimates used in the permit application are correct and provide information for future air permit applications

  1. Influence of The Arrangement of Materials and Microstructural Analysis During FSW of AZ80A

    Sevvel P.

    2017-09-01

    Full Text Available The main objective of this paper is to produce defect free weldments with improved properties during friction stir welding of dissimilar Mg alloys. The influence of the anisotropic arrangement of materials when AZ80A Mg alloy is taken as advancing side and AZ91C Mg alloy as retreating side and vice versa with respect to their mechanical properties and microstructural characteristics were investigated. The effects of various FSW parameters on the quality of these joints were also analyzed and best optimized FSW parameters were suggested. Defect free sound joints with excellent mechanical properties were produced when AZ80A Mg alloy was positioned at retreating side. At the same time, it seems a little bit difficult to obtain good quality joints with the contrary arrangement of materials. These investigations revealed that materials having inferior plastic deformability must be kept at the advancing side to obtain sound joints during FSW of dissimilar alloys of Magnesium.

  2. Enzymatic production of sterculic acid from the novel Phoenix tree seed oil: Optimization and kinetic study

    Hou, X.; Sun, S.

    2017-01-01

    Phoenix tree (Firmiana simplex) seed oil is a novel oil which is rich in sterculic acid. Sterculic acid, a cyclopropene fatty acid, can be used as the inhibitor of the stearoyl-CoA desaturase system and mammary carcinomas growth. In this work, Lipozyme TLIM-catalyzed hydrolysis of the novel Phoenix tree seed oil was used to prepare sterculic acid. High temperature GC-FID and the degree of hydrolysis (DH) were used to monitor the reaction progress. Effects of reaction variables on the hydrolysis were evaluated and optimized using response surface methodology. Results showed that sterculic acid can be successfully prepared from the novel seed oil, and the effect of reaction variables on the hydrolysis decreased in the order of reaction time > enzyme load > temperature. A high yield of fatty acids (DH, 98.2±0.8%) can be obtained under optimized conditions (45 ºC, mass ratio of water to oil 10:1, enzyme load 10%, and 18 h). The Arrhenius equation for the hydrolysis was LnV0 = 9.12 − 4721/T. The activation energy was 39.25KJ/mol. The kinetic values for Vmax, K/m were 0.232mol/(L∙min) and 0.084 mol/L, respectively. [es

  3. Possible Calcite and Magnesium Perchlorate Interaction in the Mars Phoenix Thermal and Evolved Gas Analyzer (TEGA)

    Cannon, K. M.; Sutter, B.; Ming, D. W.; Boynton, W. V.; Quinn, R. C.

    2012-01-01

    The Mars Phoenix Lander's TEGA instrument detected a calcium carbonate phase decomposing at high temperatures (approx.700 C) from the Wicked Witch soil sample [1]. TEGA also detected a lower temperature CO2 release between 400 C and 680 C [1]. Possible explanations given for this lower temperature CO2 release include thermal decomposition of Mg or Fe carbonates, a zeolitictype desorption reaction, or combustion of organic compounds in the soil [2]. The detection of 0.6 wt % soluble perchlorate by the Wet Chemistry Laboratory (WCL) on Phoenix [3] has implications for the possibility of organic molecules in the soil. Ming et al. [4] demonstrated that perchlorates could have oxidized organic compounds to CO2 in TEGA, preventing detection of their characteristic mass fragments. Here, we propose that a perchlorate salt and calcium carbonate present in martian soil reacted to produce the 400 C - 680 C TEGA CO2 release. The parent salts of the perchlorate on Mars are unknown, but geochemical models using WCL data support the possible dominance of Mg-perchlorate salts [5]. Mg(ClO4)2 6H2O is the stable phase at ambient martian conditions [6], and breaks down at lower temperatures than carbonates giving off Cl2 and HCl gas [7,8]. Devlin and Herley [7] report two exotherms at 410-478 C and 473-533 C which correspond to the decomposition of Mg(ClO4)2.

  4. Ice Lens Formation and Frost Heave at the Phoenix Landing Site

    Zent, A. P.; Sizemore, H. G.; Remple, A. W.

    2011-01-01

    Several lines of evidence indicate that the volume of shallow ground ice in the martian high latitudes exceeds the pore volume of the host regolith. Boynton et al. found an optimal fit to the Mars Odyssey Gamma Ray Spectrometer (GRS) data at the Phoenix landing site by modeling a buried layer of 50-75% ice by mass (up to 90% ice by volume). Thermal and optical observations of recent impact craters in the northern hemisphere have revealed nearly pure ice. Ice deposits containing only 1-2% soil by volume were excavated by Phoenix. The leading hypothesis for the origin of this excess ice is that it developed in situ by a mechanism analogous to the formation of terrestrial ice lenses and needle ice. Problematically, terrestrial soil-ice segregation is driven by freeze/thaw cycling and the movement of bulk water, neither of which are expected to have occurred in the geologically recent past on Mars. If however ice lens formation is possible at temperatures less than 273 K, there are possible implications for the habitability of Mars permafrost, since the same thin films of unfrozen water that lead to ice segregation are used by terrestrial psychrophiles to metabolize and grow down to temperatures of at least 258 K.

  5. Phoenix flagships: Conservation values and guanaco reintroduction in an anthropogenic landscape.

    Lindon, Adrien; Root-Bernstein, Meredith

    2015-09-01

    Multiple forms of valuation contribute to public acceptance of conservation projects. Here, we consider how esthetic, intrinsic, and utilitarian values contribute to public attitudes toward a proposed reintroduction of guanaco (Lama guanicoe) in a silvopastoral system of central Chile. The nexus among landscape perceptions and valuations, support for reintroductions, and management of anthropogenic habitats is of increasing interest due to the proliferation of conservation approaches combining some or all of these elements, including rewilding and reconciliation ecology, for example. We assessed attitudes and values through an online questionnaire for residents of Santiago, Chile, using multiple methods including photo-montages and Likert scale assessments of value-based statements. We also combined the questionnaire approach with key informant interviews. We find strong support for the reintroduction of guanacos into the Chilean silvopastoral system ('espinal') in terms of esthetic and intrinsic values but less in terms of utilitarian values. Respondents preferred a scenario of espinal with guanacos and expressed interest in visiting it, as well as support for the reintroduction project on the basis that guanacos are native to central Chile. We suggest that reintroduced guanacos could serve as a 'phoenix flagship species' for espinal conservation, that is, a flagship species that has gone regionally extinct and is known but not associated with the region in the cultural memory. We consider how the lack of local cultural identity can both help and weaken phoenix flagships, which we expect to become more common.

  6. A biometeorology study of climate and heat-related morbidity in Phoenix from 2001 to 2006

    Golden, Jay S.; Hartz, Donna; Brazel, Anthony; Luber, George; Phelan, Patrick

    2008-07-01

    Heat waves kill more people in the United States than hurricanes, tornadoes, earthquakes, and floods combined. Recently, international attention focused on the linkages and impacts of human health vulnerability to urban climate when Western Europe experienced over 30,000 excess deaths during the heat waves of the summer of 2003—surpassing the 1995 heat wave in Chicago, Illinois, that killed 739. While Europe dealt with heat waves, in the United States, Phoenix, Arizona, established a new all-time high minimum temperature for the region on July 15, 2003. The low temperature of 35.5°C (96°F) was recorded, breaking the previous all-time high minimum temperature record of 33.8°C (93°F). While an extensive literature on heat-related mortality exists, greater understanding of influences of heat-related morbidity is required due to climate change and rapid urbanization influences. We undertook an analysis of 6 years (2001 2006) of heat-related dispatches through the Phoenix Fire Department regional dispatch center to examine temporal, climatic and other non-spatial influences contributing to high-heat-related medical dispatch events. The findings identified that there were no significant variations in day-of-week dispatch events. The greatest incidence of heat-related medical dispatches occurred between the times of peak solar irradiance and maximum diurnal temperature, and during times of elevated human comfort indices (combined temperature and relative humidity).

  7. Analysis of Phoenix Anomalies and IV & V Findings Applied to the GRAIL Mission

    Larson, Steve

    2012-01-01

    NASA IV&V was established in 1993 to improve safety and cost-effectiveness of mission critical software. Since its inception the tools and strategies employed by IV&V have evolved. This paper examines how lessons learned from the Phoenix project were developed and applied to the GRAIL project. Shortly after selection, the GRAIL project initiated a review of the issues documented by IV&V for Phoenix. The motivation was twofold: the learn as much as possible about the types of issues that arose from the flight software product line slated for use on GRAIL, and to identify opportunities for improving the effectiveness of IV&V on GRAIL. The IV&V Facility provided a database dump containing 893 issues. These were categorized into 16 bins, and then analyzed according to whether the project responded by changing the affected artifacts or using as-is. The results of this analysis were compared to a similar assessment of post-launch anomalies documented by the project. Results of the analysis were discussed with the IV&V team assigned to GRAIL. These discussions led to changes in the way both the project and IV&V approached the IV&V task, and improved the efficiency of the activity.

  8. Morning Frost in Trench Dug by Phoenix, Sol 113 (False Color)

    2008-01-01

    This image from the Surface Stereo Imager on NASA's Phoenix Mars Lander shows morning frost inside the 'Snow White' trench dug by the lander, in addition to subsurface ice exposed by use of a rasp on the floor of the trench. The camera took this image at about 9 a.m. local solar time during the 113th Martian day of the mission (Sept. 18, 2008). Bright material near and below the four-by-four set of rasp holes in the upper half of the image is water-ice exposed by rasping and scraping in the trench earlier the same morning. Other bright material especially around the edges of the trench, is frost. Earlier in the mission, when the sun stayed above the horizon all night, morning frost was not evident in the trench. This image is presented in false color that enhances the visibility of the frost. The trench is 4 to 5 centimeters (about 2 inches) deep, about 23 centimeters (9 inches) wide. Phoenix landed on a Martian arctic plain on May 25, 2008. The mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.

  9. Radio variability in the Phoenix Deep Survey at 1.4 GHz

    Hancock, P. J.; Drury, J. A.; Bell, M. E.; Murphy, T.; Gaensler, B. M.

    2016-09-01

    We use archival data from the Phoenix Deep Survey to investigate the variable radio source population above 1 mJy beam-1 at 1.4 GHz. Given the similarity of this survey to other such surveys we take the opportunity to investigate the conflicting results which have appeared in the literature. Two previous surveys for variability conducted with the Very Large Array (VLA) achieved a sensitivity of 1 mJy beam-1. However, one survey found an areal density of radio variables on time-scales of decades that is a factor of ˜4 times greater than a second survey which was conducted on time-scales of less than a few years. In the Phoenix deep field we measure the density of variable radio sources to be ρ = 0.98 deg-2 on time-scales of 6 months to 8 yr. We make use of Wide-field Infrared Survey Explorer infrared cross-ids, and identify all variable sources as an active galactic nucleus of some description. We suggest that the discrepancy between previous VLA results is due to the different time-scales probed by each of the surveys, and that radio variability at 1.4 GHz is greatest on time-scales of 2-5 yr.

  10. Corrosion behaviour and in vitro/in vivo biocompatibility of surface-modified AZ31 alloy; Comportamiento frente a la corrosion y biocompatibilidad in vitrolin vivo de la aleacion AZ31 modificada superficialmente

    Carboneras, M.; Iglesias, C.; Perez-Maceda, B. T.; Valle, J. A. de; Garcia-Alonso, M. C.; Alobera, M. A.; Clemente, C.; Rubio, J. C.; Escudero, M. I.; Lozano, R. M.

    2011-07-01

    The present work evaluates the corrosion behaviour and the in vitro/in vivo biocompatibility of the AZ31 magnesium alloy, which fulfills the mechanical requirements of bone. The corrosion kinetic of as-received AZ31 alloy was not compatible with the cell growth. To improve its performance, the AZ31 alloy was surface modified by a chemical conversion treatment in hydrofluoric acid. The magnesium fluoride layer generated by the surface treatment of AZ31 alloy enhances its corrosion behaviour, allowing the in vitro growth of osteoblastic cells over the surface and the in vivo formation of a highly compact layer of new bone tissue. These results lead to consider the magnesium fluoride coating as necessary for potential use of the AZ31 alloy as biodegradable and absorbable implant for bone repair. (Author) 18 refs.

  11. Microstructure and corrosion behavior of electrodeposited nano-crystalline nickel coating on AZ91 Mg alloy

    Zarebidaki, Arman, E-mail: arman.zare@iauyazd.ac.ir; Mahmoudikohani, Hassan, E-mail: hassanmahmoudi.k@gmail.com; Aboutalebi, Mohammad-Reza

    2014-12-05

    Highlights: • Activation, zincating, and Cu electrodeposition were used as pretreatment processes for electrodeposition of nickel coatings. • Nano-crystalline nickel coatings were successfully electrodeposited onto the AZ91 Mg alloys. • Effect of nickel electrodeposited coating on the corrosion resistance of AZ91 Mg alloy has been studied. - Abstract: In order to enhance the corrosion resistance, nickel coating was electrodeposited onto AZ91 Mg alloy. Activation, zincating, and Cu electrodeposition used as pretreatment processes for better adhesion and corrosion performance of the nickel over layer. The corrosion properties of the AZ91 Mg alloy, nickel electroplated AZ91 Mg alloy, and pure nickel was assessed via polarization and electrochemical impedance spectroscopy (EIS) methods in 3.5 wt% NaCl solution. Moreover, the structure of the coating was investigated by means of X-ray diffraction, whereas specimen’s morphology and elemental composition were analyzed using scanning electron microscope (SEM) equipped with energy dispersive spectrometer (EDS). Measurements revealed that the coating has a nano-crystalline structure with the grain size of 95 nm. Corrosion results showed superior corrosion resistance for the coated AZ91 Mg alloy as the corrosion current density decreased from 2.5 × 10{sup −4} A cm{sup −2}, for the uncoated sample, to 1.5 × 10{sup −5} A cm{sup −2}, for coated specimen and the corrosion potential increased from −1.55 V to −0.98 V (vs. Ag/AgCl) at the same condition.

  12. Corrosion and mechanical performance of AZ91 exposed to simulated inflammatory conditions.

    Brooks, Emily K; Der, Stephanie; Ehrensberger, Mark T

    2016-03-01

    Magnesium (Mg) and its alloys, including Mg-9%Al-1%Zn (AZ91), are biodegradable metals with potential use as temporary orthopedic implants. Invasive orthopedic procedures can provoke an inflammatory response that produces hydrogen peroxide (H2O2) and an acidic environment near the implant. This study assessed the influence of inflammation on both the corrosion and mechanical properties of AZ91. The AZ91 samples in the inflammatory protocol were immersed for three days in a complex biologically relevant electrolyte (AMEM culture media) that contained serum proteins (FBS), 150 mM of H2O2, and was titrated to a pH of 5. The control protocol immersed AZ91 samples in the same biologically relevant electrolyte (AMEM & FBS) but without H2O2 and the acid titration. After 3 days all samples were switched into fresh AMEM & FBS for an additional 3-day immersion. During the initial immersion, inflammatory protocol samples showed increased corrosion rate determined by mass loss testing, increased Mg and Al ion released to solution, and a completely corroded surface morphology as compared to the control protocol. Although corrosion in both protocols slowed once the test electrolyte solution was replaced at 3 days, the samples originally exposed to the simulated inflammatory conditions continued to display enhanced corrosion rates as compared to the control protocol. These lingering effects may indicate the initial inflammatory corrosion processes modified components of the surface oxide and corrosion film or initiated aggressive localized processes that subsequently left the interface more vulnerable to continued enhanced corrosion. The electrochemical properties of the interfaces were also evaluated by EIS, which found that the corrosion characteristics of the AZ91 samples were potentially influenced by the role of intermediate adsorption layer processes. The increased corrosion observed for the inflammatory protocol did not affect the flexural mechanical properties of the AZ91

  13. Blocking spinal CCR2 with AZ889 reversed hyperalgesia in a model of neuropathic pain

    Vaillancourt François

    2010-12-01

    Full Text Available Abstract Background The CCR2/CCL2 system has been identified as a regulator in the pathogenesis of neuropathy-induced pain. However, CCR2 target validation in analgesia and the mechanism underlying antinociception produced by CCR2 antagonists remains poorly understood. In this study, in vitro and in vivo pharmacological approaches using a novel CCR2 antagonist, AZ889, strengthened the hypothesis of a CCR2 contribution to neuropathic pain and provided confidence over the possibilities to treat neuropathic pain with CCR2 antagonists. Results We provided evidence that dorsal root ganglia (DRG cells harvested from CCI animals responded to stimulation by CCL2 with a concentration-dependent calcium rise involving PLC-dependent internal stores. This response was associated with an increase in evoked neuronal action potentials suggesting these cells were sensitive to CCR2 signalling. Importantly, treatment with AZ889 abolished CCL2-evoked excitation confirming that this activity is CCR2-mediated. Neuronal and non-neuronal cells in the spinal cord were also excited by CCL2 applications indicating an important role of spinal CCR2 in neuropathic pain. We next showed that in vivo spinal intrathecal injection of AZ889 produced dose-dependent analgesia in CCI rats. Additionally, application of AZ889 to the exposed spinal cord inhibited evoked neuronal activity and confirmed that CCR2-mediated analgesia involved predominantly the spinal cord. Furthermore, AZ889 abolished NMDA-dependent wind-up of spinal withdrawal reflex pathway in neuropathic animals giving insight into the spinal mechanism underlying the analgesic properties of AZ889. Conclusions Overall, this study strengthens the important role of CCR2 in neuropathic pain and highlights feasibility that interfering on this mechanism at the spinal level with a selective antagonist can provide new analgesia opportunities.

  14. Electrochemical polymerization of pyrrole over AZ31 Mg alloy for biomedical applications

    Srinivasan, A.; Ranjani, P.; Rajendran, N.

    2013-01-01

    Highlights: ► Polymerization of pyrrole over AZ31 Mg was carried out using cyclic voltammetry. ► Pyrrole concentration was optimized to accomplish the adherent and uniform coating. ► Effect of monomer concentration on the surface morphology was discussed. ► Corrosion resistance of AZ31 Mg in SBF was studied as a function of Py concentration. ► PPy coated AZ31 Mg alloy exhibited enhanced corrosion resistance at 0.25 M of Py. -- Abstract: Electrochemical polymerization of pyrrole (Py) from aqueous salicylate solution over AZ31 Mg alloy was carried out using cyclic voltammetry (CV). The effect of monomer concentration on the surface and electrochemical corrosion in simulated body fluid (SBF) were analysed. Attenuated total reflection-infrared (ATR-IR) spectra showed the characteristic ring stretching peaks for polypyrrole (PPy). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) studies exhibited typical cauliflower morphology with rough surface for PPy coated AZ31 Mg alloy. Open circuit potential measurement and potentiodynamic polarization studies revealed that the coating prepared using 0.25 M of Py had positive shift of about 120 mV in corrosion potential and lower corrosion current density (0.03 mA/cm 2 ) compared to other concentrations and uncoated AZ31 Mg alloy (0.25 mA/cm 2 ). Electrochemical impedance spectroscopic (EIS) studies of uncoated and PPy coated Mg alloy in SBF revealed three-time constants behaviour with about one order of increment in impedance value for 0.25 M of Py

  15. Assessing the ecosystem service potential of Tucson AZ's urban forest

    Pavao-Zuckerman, M.

    2011-12-01

    Urbanization is arguably one of the most dramatic forms of landscape change, and an important anthropogenic influence on the structure and function of ecosystems. Cities have obvious impacts on local ecologies and environments, such as shifts in species diversity and alteration of local microclimates. While scientists are now familiar with many of these localized impacts of urbanization, cities and suburban areas contribute to 10-15 % of surface land cover in the conterminous U.S., pointing to the potential, yet poorly understood, contribution of cities to regional, national, and global carbon (C) and energy budgets. As cities continue to expand urban ecologists place more emphasis on understanding the functions of urban ecosystems and the ecosystem services (e.g. habitat, air, and water quality) that cities provide. While studies demonstrate that the urban environment alters the structure and function of remnant patches of native ecosystems relative to their non-urban counterparts, the ability of restoration, planning, and design to improve the provision of ecosystem services is a new approach within ecology. One strategy involves green urban design, or using ecological principles for planning or reinvigorating certain ecological processes, in cities. Increasing the amount of vegetative cover can reduce this effect by reinforcing ecosystem services in cities, including shading of surfaces, promotion of cooling through evapotranspiration, and the sequestration of atmospheric CO2 in plant tissues and soils. However, the on-the-ground reality of such strategies is relatively unknown. A pilot study is being conducted in Tucson, AZ to investigate the impact of increasing the cover of trees in the urban landscape on local microclimates and the urban heat island. Trees (Velvet Mesquite, Chilean Mesquite, and Desert Willow) were planted in two neighborhoods in Tucson in 1990. We are collecting data during the summer 2011 monsoon (DBH, crown volume, and hemispherical

  16. 78 FR 34403 - Notice of Availability of the Record of Decision for the Quartzsite Solar Energy Project, AZ

    2013-06-07

    ...; AZA34666] Notice of Availability of the Record of Decision for the Quartzsite Solar Energy Project, AZ... Solar Energy Project (QSEP). The Acting Assistant Secretary for Land and Minerals Management approved...: http://www.blm.gov/az/st/en/prog/energy/solar/quartzsite_solar_energy.html . FOR FURTHER INFORMATION...

  17. Differential deposition of H2A.Z in rice seedling tissue during the day-night cycle.

    Zhang, Kang; Xu, Wenying; Wang, Chunchao; Yi, Xin; Su, Zhen

    2017-03-04

    Chromatin structure has an important role in modulating gene expression. The incorporation of histone variants into the nucleosome leads to important changes in the chromatin structure. The histone variant H2A.Z is highly conserved between different species of fungi, animals, and plants. However, dynamic changes to H2A.Z in rice have not been reported during the day-night cycle. In this study, we generated genome wide maps of H2A.Z for day and night time in harvested seedling tissues by combining chromatin immunoprecipitation and high-throughput sequencing. The analysis results for the H2A.Z data sets detected 7099 genes with higher depositions of H2A.Z in seedling tissues harvested at night compared with seedling tissues harvested during the day, whereas 4597 genes had higher H2A.Z depositions in seedlings harvested during the day. The gene expression profiles data suggested that H2A.Z probably negatively regulated gene expression during the day-night cycle and was involved in many important biologic processes. In general, our results indicated that H2A.Z may play an important role in plant responses to the diurnal oscillation process.

  18. An exponential material model for prediction of the flow curves of several AZ series magnesium alloys in tension and compression

    Fereshteh-Saniee, F.; Barati, F.; Badnava, H.; Fallah Nejad, Kh.

    2012-01-01

    Highlights: ► The exponential model can represent flow behaviors of AZ series Mg alloys very well. ► Strain rate sensitivities of AZ series Mg alloys in compression are nearly the same. ► Effect of zinc element on tensile activation energy is higher than on compressive one. ► Activation energies of AZ80 and AZ81 in tension were greater than in compression. ► Tensile and compressive rate sensitivities of AZ80 are not close to each other. -- Abstract: This paper is concerned with flow behaviors of several magnesium alloys, such as AZ31, AZ80 and AZ81, in tension and compression. The experiments were performed at elevated temperatures and for various strain rates. In order to eliminate the effect of inhomogeneous deformation in tensile and compression tests, the Bridgeman’s and numerical correction factors were respectively employed. A two-section exponential mathematical model was also utilized for prediction of flow stresses of different magnesium alloys in tension and compression. Moreover, based on the compressive flow model proposed, the peak stress and the relevant true strain could be estimated. The true stress and strain of the necking point can also be predicted using the corresponding relations. It was found that the flow behaviors estimated by the exponential flow model were encouragingly in very good agreement with experimental findings.

  19. Formability analysis of sheet metals by cruciform testing

    Güler, B.; Alkan, K.; Efe, M.

    2017-09-01

    Cruciform biaxial tests are increasingly becoming popular for testing the formability of sheet metals as they achieve frictionless, in-plane, multi-axial stress states with a single sample geometry. However, premature fracture of the samples during testing prevents large strain deformation necessary for the formability analysis. In this work, we introduce a miniature cruciform sample design (few mm test region) and a test setup to achieve centre fracture and large uniform strains. With its excellent surface finish and optimized geometry, the sample deforms with diagonal strain bands intersecting at the test region. These bands prevent local necking and concentrate the strains at the sample centre. Imaging and strain analysis during testing confirm the uniform strain distributions and the centre fracture are possible for various strain paths ranging from plane-strain to equibiaxial tension. Moreover, the sample deforms without deviating from the predetermined strain ratio at all test conditions, allowing formability analysis under large strains. We demonstrate these features of the cruciform test for three sample materials: Aluminium 6061-T6 alloy, DC-04 steel and Magnesium AZ31 alloy, and investigate their formability at both the millimetre scale and the microstructure scale.

  20. On Jovian plasma sheet structure

    Khurana, K.K.; Kivelson, M.G.

    1989-01-01

    The authors evaluate several models of Jovian plasma sheet structure by determining how well they organize several aspects of the observed Voyager 2 magnetic field characteristics as a function of Jovicentric radial distance. It is shown that in the local time sector of the Voyager 2 outbound pass (near 0300 LT) the published hinged-magnetodisc models with wave (i.e., models corrected for finite wave velocity effects) are more successful than the published magnetic anomaly model in predicting locations of current sheet crossings. They also consider the boundary between the plasma sheet and the magnetotail lobe which is expected to vary slowly with radial distance. They use this boundary location as a further test of the models of the magnetotail. They show that the compressional MHD waves have much smaller amplitude in the lobes than in the plasma sheet and use this criterion to refine the identification of the plasma-sheet-lobe boundary. When the locations of crossings into and out of the lobes are examined, it becomes evident that the magnetic-anomaly model yields a flaring plasma sheet with a halfwidth of ∼ 3 R J at a radial distance of 20 R J and ∼ 12 R J at a radial distance of 100 R J . The hinged-magnetodisc models with wave, on the other hand, predict a halfwidth of ∼ 3.5 R J independent of distance beyond 20 R J . New optimized versions of the two models locate both the current sheet crossings and lobe encounters equally successfully. The optimized hinged-magnetodisc model suggests that the wave velocity decreases with increasing radial distance. The optimized magnetic anomaly model yields lower velocity contrast than the model of Vasyliunas and Dessler (1981)

  1. Qualitative Research of AZ31 Magnesium Alloy Aircraft Brackets Produced by a New Forging Method

    Dziubińska A.

    2016-06-01

    Full Text Available The paper reports a selection of numerical and experimental results of a new closed-die forging method for producing AZ31 magnesium alloy aircraft brackets with one rib. The numerical modelling of the new forming process was performed by the finite element method.The distributions of stresses, strains, temperature and forces were examined. The numerical results confirmed that the forgings produced by the new forming method are correct. For this reason, the new forming process was verified experimentally. The experimental results showed good agreement with the numerical results. The produced forgings of AZ31 magnesium alloy aircraft brackets with one rib were then subjected to qualitative tests.

  2. Influence of Zeolite Coating on the Corrosion Resistance of AZ91D Magnesium Alloy.

    Banerjee, P Chakraborty; Woo, Ren Ping; Grayson, Sam Matthew; Majumder, Amrita; Raman, R K Singh

    2014-08-22

    The protective performance of zeolite coating on AZ91D magnesium alloy was evaluated using potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS) in 0.1 M sodium chloride solution (NaCl). Electrical equivalent circuit (EEC) was developed based upon hypothetical corrosion mechanisms and simulated to correspond to the experimental data. The morphology and the chemical nature of the coating were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Post corrosion morphologies of the zeolite coated and the uncoated AZ91D alloy were investigated using SEM. The corrosion resistance of the zeolite coated specimen was at least one order of magnitude higher than the uncoated specimen.

  3. Augmenting the Energy-Saving Impact of IEEE 802.3az via the Control Plane

    Thaenchaikun , Chakadkit; Jakllari , Gentian; Paillassa , Béatrice

    2015-01-01

    International audience; IEEE 802.3az, the recent standard for Energy Efficient Ethernet, is one of the main contributions of the ICT industry to the global quest for energy efficiency. Energy consumption reduction is accomplished by essentially replacing the continuous IDLE of legacy IEEE 802.3 cards with a Low Power Idle. While this is an important step in the right direction, studies have shown that the energy saving with IEEE 802.3az highly depends on the traffic load and stops for link ut...

  4. Anticorrosive magnesium hydroxide coating on AZ31 magnesium alloy by hydrothermal method

    Zhu Yanying; Wu Guangming; Xing Guangjian; Li Donglin; Zhao Qing; Zhang Yunhong

    2009-01-01

    Magnesium alloys are potential biodegradable biomaterials in orthopedic surgery. However, the rapid degradation rate has limited their application in biomedical field. A great deal of studies have been done to improve the resistance of magnesium alloys. In this article, An anticorrosive magnesium hydroxide coating with a thickness of approximately 100μm was formed on an AZ31 magnesium alloy by hydrothermal method. The morphology of the coatings were observed by an optical microscope and SEM. And the samples were soaked in hank's solution (37 deg. C) to investigate the corrosion resistance. Magnesium alloy AZ31 with magnesium hydroxide coatings present superior corrosion resistance than untreated samples.

  5. Structure of the AZ91 alloy pressure castings fabricated of home scrap containing charge

    Z. Konopka

    2011-04-01

    Full Text Available The influence of the AZ91 alloy home scrap addition to the metal charge on both the structure and the selected mechanical propertiesof pressure castings was examined in this article. Two heats were made using different components, the first with only pure AZ91 alloyingots in the charge, and the second containing 30 wt % of home scrap. The hot chamber 3 MN machine was used for casting. Thestructures of the castings and their Brinell hardness were examined for both cases. A strong refinement of crystals was observed in castings made with the contribution of the recycled material. Any significant differences in castings hardness were not observed.

  6. Acceptance Test Report for the 241-AZ-101 Ultrasonic Interface Level Analyzer

    ANDREWS, J.E.

    2000-01-27

    This document comprises the Acceptance Test Report for the 241-AZ-101 Ultrasonic Interface Level Analyzer. This document presents the results of Acceptance Testing of the 241-AZ-101 Ultrasonic Interface Level Analyzers (URSILLAs). Testing of the URSILLAs was performed in accordance with ATP-260-001, ''URSILLA Pre-installation Acceptance Test Procedure''. The objective of the testing was to verify that all equipment and components function in accordance with design specifications and original equipment manufacturer's specifications.

  7. Patrón de consumo e ingestas recomendadas de azúcar

    Joan Quiles i Izquierdo

    2013-01-01

    Los azúcares son hidratos de carbono con sabor dulce que proveen energía al organismo. El cerebro adulto utiliza aproximadamente 140 g de glucosa al día, cantidad que puede representar hasta el 50% del total de hidratos de carbono que se consumen. En nuestro país el patrón de consumo de azúcar en alimentos permanece constante, mientras que el consumo de bebidas refrescantes presenta un aumento en los últimos cuatro años. La Encuesta Nacional de Ingesta Dietética de España (ENIDE, 2010-11) est...

  8. Automobile sheet metal part production with incremental sheet forming

    İsmail DURGUN

    2016-02-01

    Full Text Available Nowadays, effect of global warming is increasing drastically so it leads to increased interest on energy efficiency and sustainable production methods. As a result of adverse conditions, national and international project platforms, OEMs (Original Equipment Manufacturers, SMEs (Small and Mid-size Manufacturers perform many studies or improve existing methodologies in scope of advanced manufacturing techniques. In this study, advanced manufacturing and sustainable production method "Incremental Sheet Metal Forming (ISF" was used for sheet metal forming process. A vehicle fender was manufactured with or without die by using different toolpath strategies and die sets. At the end of the study, Results have been investigated under the influence of method and parameters used.Keywords: Template incremental sheet metal, Metal forming

  9. Magnetic and optical properties of airborne dust and settling rates of dust at the Phoenix landing site

    Drube...[], Line; Leer, Kristoffer; Madsen, Morten Bo

    2010-01-01

    The Magnetic Properties Experiment (referred to as iSweep or Caltarget) onboard the Phoenix lander was executed in the arctic region of Mars during the mission's 152 sols lifetime. The iSweep experiment involved periodic multispectral imaging of a series of permanent ring magnets. It was designed...

  10. A Study of the Physiological Factors Affecting the Nature of the Adult Learner in the Phoenix Air National Guard.

    Torbert, James Brison

    An investigation reviewed current literature in the field of physiological factors affecting the adult learning environment. These findings were compared to the academic learning environment at the Phoenix Air National Guard. The end product was a set of recommendations for management to implement in order to improve the learning climate for the…

  11. Uranium mining sites - Thematic sheets

    2009-01-01

    A first sheet proposes comments, data and key numbers about uranium extraction in France: general overview of uranium mining sites, status of waste rock and tailings after exploitation, site rehabilitation. The second sheet addresses the sources of exposure to ionizing radiations due to ancient uranium mining sites: discussion on the identification of these sources associated with these sites, properly due to mining activities or to tailings, or due to the transfer of radioactive substances towards water and to the contamination of sediments, description of the practice and assessment of radiological control of mining sites. A third sheet addresses the radiological exposure of public to waste rocks, and the dose assessment according to exposure scenarios: main exposure ways to be considered, studied exposure scenarios (passage on backfilled path and grounds, stay in buildings built on waste rocks, keeping mineralogical samples at home). The fourth sheet addresses research programmes of the IRSN on uranium and radon: epidemiological studies (performed on mine workers; on French and on European cohorts, French and European studies on the risk of lung cancer associated with radon in housing), study of the biological effects of chronic exposures. The last sheet addresses studies and expertises performed by the IRSN on ancient uranium mining sites in France: studies commissioned by public authorities, radioactivity control studies performed by the IRSN about mining sites, participation of the IRSN to actions to promote openness to civil society

  12. Comportamiento mecánico de la aleación AZ31 reforzada con nanofibras de carbono

    Adeva, P.

    2010-12-01

    Full Text Available The aim of this study is to investigate the effect of reinforcing AZ31 with carbon nanofibres. The materials AZ31, AZ31-1 % C y AZ31-2 % C were produced by a conventional powder metallurgy route consisting of mechanical mixing of nanofibres and powders of AZ31, cool compactation and extrusion at 350 °C. After extrusion the three materials exhibited a recrystallized microstructure of similar grain size, fine and rather inhomogeneous. Furthermore, they presented a weak fibre texture with basal plane parallel to the extrusion direction. The tensile properties were affected by the nanofibres presence only at 100 °C. At this temperature, yield strength and tensile strength were 30% higher than in the unreinforced alloy.

    En este trabajo se ha estudiado el efecto de la adición de nanofibras de carbono en las propiedades mecánicas de la aleación AZ31 procesada por una ruta pulvimetalúrgica convencional. Se prepararon tres materiales, AZ31, AZ31- 1 % C y AZ31-2 % C. Tras una mezcla mecánica de las nanofibras con los polvos de AZ31, se precompactaron en frío y se extruyeron a 350 °C. Los tres presentan una microestructura recristalizada con un tamaño de grano similar, fino aunque algo heterogéneo. Los tres materiales presentan una débil textura de fibra con el plano basal paralelo a la dirección de extrusión. Las propiedades mecánicas a tracción únicamente se ven afectadas por la presencia de nanofibras a 100 °C superando los materiales reforzados en un 30 % a los valores de límite elástico y resistencia de la aleación sin reforzar.

  13. Semi-solid twin-roll casting process of magnesium alloy sheets

    Watari, H.; Davey, K.; Rasgado, M.T. Alonso; Haga, T.; Koga, N.

    2004-01-01

    An experimental approach has been performed to ascertain the effectiveness of semi-solid strip casting using a horizontal twin roll caster. The demand for light-weight products with high strength has grown recently due to the rapid development of automobile and aircraft technology. One key to such development has been utilization of magnesium alloys, which can potentially reduce the total product weight. However, the problems of utilizing magnesium alloys are still mainly related to high manufacturing cost. One of the solutions to this problem is to develop magnesium casting-rolling technology in order to produce magnesium sheet products at competitive cost for commercial applications. In this experiment, magnesium alloy AZ31B was used to ascertain the effectiveness of semi-solid roll strip casting for producing magnesium alloy sheets. The temperature of the molten magnesium, and the roll speeds of the upper and lower rolls, (which could be changed independently), were varied to find an appropriate manufacturing condition. Rolling and heat treatment conditions were changed to examine which condition would be appropriate for producing wrought magnesium alloys with good formability. Microscopic observation of the crystals of the manufactured wrought magnesium alloys was performed. It has been found that a limiting drawing ratio of 2.7 was possible in a warm deep drawing test of the cast magnesium alloy sheets after being hot rolled

  14. Root-growth-inhibiting sheet

    Burton, F.G.; Cataldo, D.A.; Cline, J.F.; Skiens, W.E.; Van Voris, P.

    1993-01-26

    In accordance with this invention, a porous sheet material is provided at intervals with bodies of a polymer which contain a 2,6-dinitroaniline. The sheet material is made porous to permit free passage of water. It may be either a perforated sheet or a woven or non-woven textile material. A particularly desirable embodiment is a non-woven fabric of non-biodegradable material. This type of material is known as a geotextile'' and is used for weed control, prevention of erosion on slopes, and other landscaping purposes. In order to obtain a root repelling property, a dinitroaniline is blended with a polymer which is attached to the geotextile or other porous material.

  15. Optimal swimming of a sheet.

    Montenegro-Johnson, Thomas D; Lauga, Eric

    2014-06-01

    Propulsion at microscopic scales is often achieved through propagating traveling waves along hairlike organelles called flagella. Taylor's two-dimensional swimming sheet model is frequently used to provide insight into problems of flagellar propulsion. We derive numerically the large-amplitude wave form of the two-dimensional swimming sheet that yields optimum hydrodynamic efficiency: the ratio of the squared swimming speed to the rate-of-working of the sheet against the fluid. Using the boundary element method, we show that the optimal wave form is a front-back symmetric regularized cusp that is 25% more efficient than the optimal sine wave. This optimal two-dimensional shape is smooth, qualitatively different from the kinked form of Lighthill's optimal three-dimensional flagellum, not predicted by small-amplitude theory, and different from the smooth circular-arc-like shape of active elastic filaments.

  16. Root-growth-inhibiting sheet

    Burton, Frederick G.; Cataldo, Dominic A.; Cline, John F.; Skiens, W. Eugene; Van Voris, Peter

    1993-01-01

    In accordance with this invention, a porous sheet material is provided at intervals with bodies of a polymer which contain a 2,6-dinitroaniline. The sheet material is made porous to permit free passage of water. It may be either a perforated sheet or a woven or non-woven textile material. A particularly desirable embodiment is a non-woven fabric of non-biodegradable material. This type of material is known as a "geotextile" and is used for weed control, prevention of erosion on slopes, and other landscaping purposes. In order to obtain a root repelling property, a dinitroaniline is blended with a polymer which is attached to the geotextile or other porous material.

  17. Ice sheet hydrology - a review

    Jansson, Peter; Naeslund, Jens-Ove [Dept. of Physical Geography and Quaternary Geology, Stockholm Univ., Stockholm (Sweden); Rodhe, Lars [Geological Survey of Sweden, Uppsala (Sweden)

    2007-03-15

    This report summarizes the theoretical knowledge on water flow in and beneath glaciers and ice sheets and how these theories are applied in models to simulate the hydrology of ice sheets. The purpose is to present the state of knowledge and, perhaps more importantly, identify the gaps in our understanding of ice sheet hydrology. Many general concepts in hydrology and hydraulics are applicable to water flow in glaciers. However, the unique situation of having the liquid phase flowing in conduits of the solid phase of the same material, water, is not a commonly occurring phenomena. This situation means that the heat exchange between the phases and the resulting phase changes also have to be accounted for in the analysis. The fact that the solidus in the pressure-temperature dependent phase diagram of water has a negative slope provides further complications. Ice can thus melt or freeze from both temperature and pressure variations or variations in both. In order to provide details of the current understanding of water flow in conjunction with deforming ice and to provide understanding for the development of ideas and models, emphasis has been put on the mathematical treatments, which are reproduced in detail. Qualitative results corroborating theory or, perhaps more often, questioning the simplifications made in theory, are also given. The overarching problem with our knowledge of glacier hydrology is the gap between the local theories of processes and the general flow of water in glaciers and ice sheets. Water is often channelized in non-stationary conduits through the ice, features which due to their minute size relative to the size of glaciers and ice sheets are difficult to incorporate in spatially larger models. Since the dynamic response of ice sheets to global warming is becoming a key issue in, e.g. sea-level change studies, the problems of the coupling between the hydrology of an ice sheet and its dynamics is steadily gaining interest. New work is emerging

  18. Modelling the Antarctic Ice Sheet

    Pedersen, Jens Olaf Pepke; Holm, A.

    2015-01-01

    to sea level high stands during past interglacial periods. A number of AIS models have been developed and applied to try to understand the workings of the AIS and to form a robust basis for future projections of the AIS contribution to sea level change. The recent DCESS (Danish Center for Earth System......The Antarctic ice sheet is a major player in the Earth’s climate system and is by far the largest depository of fresh water on the planet. Ice stored in the Antarctic ice sheet (AIS) contains enough water to raise sea level by about 58 m, and ice loss from Antarctica contributed significantly...

  19. Ice sheet hydrology - a review

    Jansson, Peter; Naeslund, Jens-Ove; Rodhe, Lars

    2007-03-01

    This report summarizes the theoretical knowledge on water flow in and beneath glaciers and ice sheets and how these theories are applied in models to simulate the hydrology of ice sheets. The purpose is to present the state of knowledge and, perhaps more importantly, identify the gaps in our understanding of ice sheet hydrology. Many general concepts in hydrology and hydraulics are applicable to water flow in glaciers. However, the unique situation of having the liquid phase flowing in conduits of the solid phase of the same material, water, is not a commonly occurring phenomena. This situation means that the heat exchange between the phases and the resulting phase changes also have to be accounted for in the analysis. The fact that the solidus in the pressure-temperature dependent phase diagram of water has a negative slope provides further complications. Ice can thus melt or freeze from both temperature and pressure variations or variations in both. In order to provide details of the current understanding of water flow in conjunction with deforming ice and to provide understanding for the development of ideas and models, emphasis has been put on the mathematical treatments, which are reproduced in detail. Qualitative results corroborating theory or, perhaps more often, questioning the simplifications made in theory, are also given. The overarching problem with our knowledge of glacier hydrology is the gap between the local theories of processes and the general flow of water in glaciers and ice sheets. Water is often channelized in non-stationary conduits through the ice, features which due to their minute size relative to the size of glaciers and ice sheets are difficult to incorporate in spatially larger models. Since the dynamic response of ice sheets to global warming is becoming a key issue in, e.g. sea-level change studies, the problems of the coupling between the hydrology of an ice sheet and its dynamics is steadily gaining interest. New work is emerging

  20. Sheet Beam Klystron Instability Analysis

    Bane, K.

    2009-01-01

    Using the principle of energy balance we develop a 2D theory for calculating growth rates of instability in a two-cavity model of a sheet beam klystron. An important ingredient is a TE-like mode in the gap that also gives a longitudinal kick to the beam. When compared with a self-consistent particle-in-cell calculation, with sheet beam klystron-type parameters, agreement is quite good up to half the design current, 65 A; at full current, however, other, current-dependent effects come in and the results deviate significantly

  1. The social balance sheet 2004

    Ph. Delhez; P. Heuse

    2005-01-01

    Each year, in the 4th quarter’s Economic Review, the National Bank examines the provisional results of the social balance sheets. As all the social balance sheets are not yet available for 2004, the study is based on a limited population of enterprises, compiled according to the principle of a constant sample. This population is made up of 38,530 enterprises employing around 1,331,000 workers in 2004. The main results of the analysis, in terms of employment, working hours, labour cost and tra...

  2. Cesium Removal From Tanks 241-AN-103 and 241-SX-105 and 241-AZ-101 and 241-AZ-102 Composite For Testing In Bench Scale Steam Reformer

    Duncan, J.B.; Huber, H.J.

    2011-01-01

    This report documents the preparation of three actual Hanford tank waste samples for shipment to the Savannah River National Laboratory (SRNL). Two of the samples were dissolved saltcakes from tank 241-AN-103 (hereafter AN-103) and tank 241-SX-105 (hereafter SX-105); one sample was a supernate composite from tanks 241-AZ-101 and 241-AZ-102 (hereafter AZ-101/102). The preparation of the samples was executed following the test plans LAB-PLAN-10-00006, Test Plan for the Preparation of Samples from Hanford Tanks 241-SX-105, 241-AN-103, 241-AN-107, and LAB-PLN-l0-00014, Test Plan for the Preparation of a Composite Sample from Hanford Tanks 241-AZ-101 and 241-AZ-102 for Steam Reformer Testing at the Savannah River National Laboratory. All procedural steps were recorded in laboratory notebook HNF-N-274 3. Sample breakdown diagrams for AN-103 and SX-105 are presented in Appendix A. The tank samples were prepared in support of a series of treatability studies of the Fluidized Bed Steam Reforming (FBSR) process using a Bench-Scale Reformer (BSR) at SRNL. Tests with simulants have shown that the FBSR mineralized waste form is comparable to low-activity waste glass with respect to environmental durability (WSRC-STI-2008-00268, Mineralization of Radioactive Wastes by Fluidized Bed Steam Reforming (FBSR): Comparisons to Vitreous Waste Forms and Pertinent Durability Testing). However, a rigorous assessment requires long-term performance data from FBSR product formed from actual Hanford tank waste. Washington River Protection Solutions, LLC (WRPS) has initiated a Waste Form Qualification Program (WP-5.2.1-2010-001, Fluidized Bed Steam Reformer Low-level Waste Form Qualification) to gather the data required to demonstrate that an adequate FBSR mineralized waste form can be produced. The documentation of the selection process of the three tank samples has been separately reported in RPP-48824, Sample Selection Process for Bench-Scale Steam Reforming Treatability Studies Using

  3. CESIUM REMOVAL FROM TANKS 241-AN-103 & 241-SX-105 & 241-AZ-101 & 241AZ-102 COMPOSITE FOR TESTING IN BENCH SCALE STEAM REFORMER

    DUNCAN JB; HUBER HJ

    2011-04-21

    This report documents the preparation of three actual Hanford tank waste samples for shipment to the Savannah River National Laboratory (SRNL). Two of the samples were dissolved saltcakes from tank 241-AN-103 (hereafter AN-103) and tank 241-SX-105 (hereafter SX-105); one sample was a supernate composite from tanks 241-AZ-101 and 241-AZ-102 (hereafter AZ-101/102). The preparation of the samples was executed following the test plans LAB-PLAN-10-00006, Test Plan for the Preparation of Samples from Hanford Tanks 241-SX-105, 241-AN-103, 241-AN-107, and LAB-PLN-l0-00014, Test Plan for the Preparation of a Composite Sample from Hanford Tanks 241-AZ-101 and 241-AZ-102 for Steam Reformer Testing at the Savannah River National Laboratory. All procedural steps were recorded in laboratory notebook HNF-N-274 3. Sample breakdown diagrams for AN-103 and SX-105 are presented in Appendix A. The tank samples were prepared in support of a series of treatability studies of the Fluidized Bed Steam Reforming (FBSR) process using a Bench-Scale Reformer (BSR) at SRNL. Tests with simulants have shown that the FBSR mineralized waste form is comparable to low-activity waste glass with respect to environmental durability (WSRC-STI-2008-00268, Mineralization of Radioactive Wastes by Fluidized Bed Steam Reforming (FBSR): Comparisons to Vitreous Waste Forms and Pertinent Durability Testing). However, a rigorous assessment requires long-term performance data from FBSR product formed from actual Hanford tank waste. Washington River Protection Solutions, LLC (WRPS) has initiated a Waste Form Qualification Program (WP-5.2.1-2010-001, Fluidized Bed Steam Reformer Low-level Waste Form Qualification) to gather the data required to demonstrate that an adequate FBSR mineralized waste form can be produced. The documentation of the selection process of the three tank samples has been separately reported in RPP-48824, Sample Selection Process for Bench-Scale Steam Reforming Treatability Studies Using

  4. Expression of P. falciparum var Genes Involves Exchange of the Histone Variant H2A.Z at the Promoter

    Petter, Michaela; Lee, Chin Chin; Byrne, Timothy J.; Boysen, Katja E.; Volz, Jennifer; Ralph, Stuart A.; Cowman, Alan F.; Brown, Graham V.; Duffy, Michael F.

    2011-01-01

    Plasmodium falciparum employs antigenic variation to evade the human immune response by switching the expression of different variant surface antigens encoded by the var gene family. Epigenetic mechanisms including histone modifications and sub-nuclear compartmentalization contribute to transcriptional regulation in the malaria parasite, in particular to control antigenic variation. Another mechanism of epigenetic control is the exchange of canonical histones with alternative variants to generate functionally specialized chromatin domains. Here we demonstrate that the alternative histone PfH2A.Z is associated with the epigenetic regulation of var genes. In many eukaryotic organisms the histone variant H2A.Z mediates an open chromatin structure at promoters and facilitates diverse levels of regulation, including transcriptional activation. Throughout the asexual, intraerythrocytic lifecycle of P. falciparum we found that the P. falciparum ortholog of H2A.Z (PfH2A.Z) colocalizes with histone modifications that are characteristic of transcriptionally-permissive euchromatin, but not with markers of heterochromatin. Consistent with this finding, antibodies to PfH2A.Z co-precipitate the permissive modification H3K4me3. By chromatin-immunoprecipitation we show that PfH2A.Z is enriched in nucleosomes around the transcription start site (TSS) in both transcriptionally active and silent stage-specific genes. In var genes, however, PfH2A.Z is enriched at the TSS only during active transcription in ring stage parasites. Thus, in contrast to other genes, temporal var gene regulation involves histone variant exchange at promoter nucleosomes. Sir2 histone deacetylases are important for var gene silencing and their yeast ortholog antagonises H2A.Z function in subtelomeric yeast genes. In immature P. falciparum parasites lacking Sir2A or Sir2B high var transcription levels correlate with enrichment of PfH2A.Z at the TSS. As Sir2A knock out parasites mature the var genes are

  5. 75 FR 11554 - Notice of Intent to Repatriate Cultural Items: Museum of Northern Arizona, Flagstaff, AZ

    2010-03-11

    ... continue to be used by traditional Navajo religious practitioners. Based on the sacred esoteric knowledge... Northern Arizona, Flagstaff, AZ, that meet the definitions of ``sacred objects'' and ``objects of cultural... the area of Farmington, NM. The 29 cultural items are 4 watercolors of sacred Navajo Yei figures and...

  6. 241-AZ-101 Waste Tank Color Video Camera System Shop Acceptance Test Report

    WERRY, S.M.

    2000-01-01

    This report includes shop acceptance test results. The test was performed prior to installation at tank AZ-101. Both the camera system and camera purge system were originally sought and procured as a part of initial waste retrieval project W-151

  7. Fault-tolerant epoxy-silane coating for corrosion protection of magnesium alloy AZ31

    Lamaka, S.V.; Xue, H.B.; Meis, N.N.A.H.; Esteves, A.C.C.; Ferreira, M.G.S.

    2015-01-01

    In this work, a hybrid epoxy-silane coating was developed for corrosion protection of magnesium alloy AZ31. The average thickness of the film produced by dip-coating procedure was 14 µm. The adhesion strength of the epoxy-silane coating to the Mg substrate was evaluated by pull-off tests and was

  8. 241-AZ-101 Waste Tank Color Video Camera System Shop Acceptance Test Report

    WERRY, S.M.

    2000-03-23

    This report includes shop acceptance test results. The test was performed prior to installation at tank AZ-101. Both the camera system and camera purge system were originally sought and procured as a part of initial waste retrieval project W-151.

  9. Laser cladding of Zr-based coating on AZ91D magnesium alloy for ...

    based coating made of Zr powder was fabricated on AZ91D magnesium alloy by laser cladding. The microstructure of the coating was characterized by XRD, SEM and TEM techniques. The wear resistance of the coating was evaluated under dry ...

  10. Flow mechanisms in creep of a short-fibre AZ91 alloy-based composite

    Pahutová, Marie; Sklenička, Václav; Kuchařová, Květa; Svoboda, Milan; Langdon, T. G.

    43 2005, č. 1 (2005), s. 34-44 ISSN 0023-432X R&D Projects: GA ČR(CZ) GA106/03/0901 Institutional research plan: CEZ:AV0Z20410507 Keywords : AZ91 magnesium alloy * metal matrix composite * short fibre reinforcement Subject RIV: JG - Metallurgy Impact factor: 0.973, year: 2005

  11. Study on fused/cast AZS refractories for deployment in vitrification of radioactive waste effluents

    Sengupta, Pranesh; Mishra, R. K.; Soudamini, N.; Sen, D.; Mazumder, S.; Kaushik, C. P.; Ajithkumar, T. G.; Banerjee, K.

    2015-12-01

    'Fused/cast Al2O3-ZrO2-SiO2 (FC-AZS)' is being considered as 'glass contact refractory' within ceramic melters, to be used for nuclear waste immobilization. Microstructural analyses reveal random distributions of baddeleyite (ZrO2) within aluminosilicate (Al2SiO5) matrix. 27Al and 29Si NMR data suggest that within aluminosilicate matrix Al occurs in both 4- and 6-fold co-ordinations whereas Si prefers a 4-fold environment. Polydispersity of pores has been studied with small-angle neutron scattering (SANS) technique. Corrosion rates of FC-AZS within 6 M HNO3, simulated wastes (500 h exposure), and borosilicate melt (975 °C, 800 h exposure) are found to be 0.38 × 103 μmy-1, 0.13 × 103 μmy-1 and 4.75 × 103 μmy-1 respectively. A comparison of chemical interaction data clearly suggests that FC-AZS exhibits better chemical durability than AZC refractory (Al2O3-ZrO2-Cr2O3, also used for similar purpose). Thermal cycling studies indicate that FC-AZS retains structural integrity (including compressive strength and density) even up to 20 cycles.

  12. 78 FR 23135 - Safety Zone; Blue Water Resort & Casino West Coast Nationals; Parker, AZ

    2013-04-18

    ...-AA00 Safety Zone; Blue Water Resort & Casino West Coast Nationals; Parker, AZ AGENCY: Coast Guard, DHS... Water Resort & Casino West Coast Nationals. This temporary safety zone is necessary to provide for the....). RPM Racing Enterprises is sponsoring the Blue Water Resort & Casino West Coast Nationals, which is...

  13. 75 FR 11939 - DNS Electronics, Chandler, AZ; Notice of Termination of Investigation

    2010-03-12

    ... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-70,654] DNS Electronics, Chandler, AZ; Notice of Termination of Investigation Pursuant to Section 223 of the Trade Act of 1974, as... on behalf of workers of DNS Electronics, Chandler, Arizona. The petitioning group of workers is...

  14. Laser cladding of Zr-based coating on AZ91D magnesium alloy for ...

    3Hubei Key Laboratory of Hydroelectric Machinery Design & Maintenance, ... To improve the wear and corrosion resistance of AZ91D magnesium alloy, Zr-based coating made of ... process that lead to inflammatory cascades which reduce bio- ... tions regarding their application as protective films on load- ... Experimental.

  15. 75 FR 5115 - Temporary Concession Contract for Lake Mead National Recreation Area, AZ/NV

    2010-02-01

    ... National Recreation Area, AZ/NV AGENCY: National Park Service, Department of the Interior. ACTION: Notice of intention to award temporary concession contract for Lake Mead National Recreation Area. SUMMARY: Pursuant to 36 CFR 51.24, public notice is hereby given that the National Park Service intends to award a...

  16. Effect of Pr addition on microstructure and mechanical properties of AZ61 magnesium alloy

    You Zhiyong

    2014-03-01

    Full Text Available To improve the strength, hardness and heat resistance of Mg-6Al-1Zn (AZ61 alloy, the effects of Pr addition on the as-cast microstructure and mechanical properties of AZ61 alloy were investigated at room and elevated temperatures by means of Brinell hardness measurement, optical microscope (OM, scanning electron microscope (SEM, energy dispersive spectroscopy (EDS, X-ray diffractometer (XRD and DNS100 electronic universal testing machine. The results show that the microstructures of Pr-containing AZ61 alloys were refined, with primary β-Mg17Al12 phase distributed homogeneously. When the addition of Pr is up to 1.2wt.%, the β phase becomes finer, and new needle-like or short-rod shaped Al11Pr3 phase and blocky AlPr phase appear. As a result, optimal tensile properties are obtained. However, greater than 1.2wt.% Pr addition leads to poorer mechanical properties due to the aggregation of the needle-like phase and large size of grains. The present research findings provide a new way for strengthening of magnesium alloys at room and elevated temperatures, and a method of producing thermally-stable AZ61 magnesium alloy.

  17. Mechanical properties of plasma-sprayed layers of aluminium and aluminium alloy on AZ 91

    Kubatík, Tomáš František; Ctibor, Pavel; Mušálek, Radek; Janata, Marek

    2017-01-01

    Roč. 51, č. 2 (2017), s. 323-327 ISSN 1580-2949 R&D Projects: GA ČR(CZ) GP14-31538P Institutional support: RVO:61389021 Keywords : plasma spraying of aluminium * adhesion of coating * wear * magnesium alloy AZ91 Subject RIV: JG - Metallurgy OBOR OECD: Materials engineering Impact factor: 0.436, year: 2016

  18. Structural evaluation of thermocouple probes for 241-AZ-101 waste tank

    Kanjilal, S.K.

    1994-01-01

    This document reports on the structural analysis of the thermocouple probe to be installed in 241-AZ-101 waste tank. The thermocouple probe is analyzed for normal pump mixing operation and potential earthquake induced loads required by the Hanford Site Design Criteria SDC-4.1

  19. Structural evaluation of thermocouple probes for 241-AZ-101 waste tank

    Kanjilal, S.K.

    1994-12-06

    This document reports on the structural analysis of the thermocouple probe to be installed in 241-AZ-101 waste tank. The thermocouple probe is analyzed for normal pump mixing operation and potential earthquake induced loads required by the Hanford Site Design Criteria SDC-4.1.

  20. Tank 241-AZ-101 steam bumping and settling Process Test report

    Winkler, C.M.

    1995-01-01

    This report summarizes the process test in which the airlift circulators in Tank 241-AZ-101 were shutdown. The test was successful, in that no extreme temperature excursions occurred. Only general data was obtianed through the use of a gamma energy probe

  1. Fatigue properties of magnesium alloy AZ91 processed by severe plastic deformation

    Fintová, Stanislava; Kunz, Ludvík

    2015-01-01

    Roč. 42, FEB (2015), s. 219-228 ISSN 1751-6161 R&D Projects: GA ČR GAP108/10/2001 Institutional support: RVO:68081723 Keywords : AZ91 magnesium alloy * ECAP * Fatigue * Crack initiation Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 2.876, year: 2015 http://www.sciencedirect.com/science/article/pii/S1751616114003713

  2. 77 FR 20356 - Foreign-Trade Zone 277-Western Maricopa County, AZ; Application for Manufacturing Authority...

    2012-04-04

    ... Maricopa County, AZ; Application for Manufacturing Authority; Suntech Arizona, Inc., (Solar Panel... facility is used for the manufacture of 275 and 290 watt solar panels for industrial use. Components and... to solar panels (duty-free) for the foreign inputs noted above. Suntech would also be exempt from...

  3. Comparison of Electrochemical Methods for the Evaluation of Cast AZ91 Magnesium Alloy

    Tkacz, J.; Minda, J.; Fintová, Stanislava; Wasserbauer, J.

    2016-01-01

    Roč. 9, č. 11 (2016), č. článku 925. ISSN 1996-1944 Institutional support: RVO:68081723 Keywords : AZ91 magnesium alloy * cathodic polarization curve * anodic polarization curve * linear polarization curve Subject RIV: JK - Corrosion ; Surface Treatment of Materials Impact factor: 2.654, year: 2016 http://www.mdpi.com/1996-1944/9/11/925

  4. In vitro corrosion of magnesium alloy AZ31 — a synergetic influence of glucose and Tris

    Li, Ling-Yu; Liu, Bin; Zeng, Rong-Chang; Li, Shuo-Qi; Zhang, Fen; Zou, Yu-Hong; Jiang, Hongwei George; Chen, Xiao-Bo; Guan, Shao-Kang; Liu, Qing-Yun

    2018-05-01

    Biodegradable Mg alloys have generated great interest for biomedical applications. Accurate predictions of in vivo degradation of Mg alloys through cost-effective in vivo evaluations require the latter to be conducted in an environment close to that of physiological scenarios. However, the roles of glucose and buffering agents in regulating the in vivo degradation performance of Mg alloys has not been elucidated. Herein, degradation behavior of AZ31 alloy is investigated by hydrogen evolution measurements, pH monitoring and electrochemical tests. Results indicate that glucose plays a content-dependent role in degradation of AZ31 alloy in buffer-free saline solution. The presence of a low concentration of glucose, i.e. 1.0 g/L, decreases the corrosion rate of Mg alloy AZ31, whereas the presence of 2.0 and 3.0 g/L glucose accelerates the corrosion rate during long term immersion in saline solution. In terms of Tris-buffered saline solution, the addition of glucose increases pH value and promotes pitting corrosion or general corrosion of AZ31 alloy. This study provides a novel perspective to understand the bio-corrosion of Mg alloys in buffering agents and glucose containing solutions.

  5. Selectividad de caña de azúcar en bovinos

    E. M. Aranda

    2009-01-01

    Full Text Available Se condujo este trabajo con el objetivo de conocer la aceptación del forraje de caña de azúcar integral en la dieta con base de pasto para bovinos adultos fistulados en rumen y duodeno estabulados; para ello, se ofreció pasto estrella africana (Cynodon plectostachyus y caña de azúcar (Saccharum officinarum mezclada con 1% de urea a voluntad, por separado. Se midió la composición de los alimentos, consumo de materia seca, pH ruminal y duodenal. Se utilizaron técnicas de la estadística descriptiva, como la media aritmética y error estándar. La proteína, paredes celulares y hemicelulosa fueron mayores para el pasto estrella. El consumo de MS fue de 46.6 y 38.1% para la caña de azúcar y el pasto, respectivamente; el pH ruminal tuvo valores de 7.3, disminuyendo a 6.7 a las 12 h.; y el pH de la digesta duodenal osciló de 3.7 a 4.7. Se concluye que hubo mayor aceptación por la caña de azúcar y el pH ruminal no indica valores que afecten la celulólisis ruminal.

  6. Corrosion behaviour of laser surface melted magnesium alloy AZ91D

    Taltavull, C.; Torres, B.; Lopez, A.J.; Rodrigo, P.; Otero, E.; Atrens, A.; Rams, J.

    2014-01-01

    A high power diode laser (HPDL) was used to produce laser surface melting (LSM) treatments on the surface of the Mg alloy AZ91D. Different treatments with different microstructures were produced by varying the laser-beam power and laser-scanning speed. Corrosion evaluation, using hydrogen evolution and electrochemical measurements, led to a relationship between microstructure and corrosion. Most corrosion rates for LSM treated specimens were within the scatter of the as-received AZ91D, whereas some treatments gave higher corrosion rates and some of the samples had corrosion rates lower than the average of the corrosion rate for AZ91D. There were differences in corroded surface morphology. Nevertheless laser treatments introduced surface discontinuities, which masked the effect of the microstructure. Removing these surface defects decreased the corrosion rate for the laser-treated samples. - Highlights: • Corrosion behavior of AZ91D Mg alloys is intimately related with its microstructure. • Laser surface melting treatments allows surface modification of the microstructure. • Different laser parameters can achieve different microstructures. • Controlling laser parameters can produce different corrosion rates and morphologies. • Increase of surface roughness due to laser treatment is relevant to the corrosion rate

  7. Confirmation of Soluble Sulfate at the Phoenix Landing Site: Implications for Martian Geochemistry and Habitability

    Kounaves, S. P.; Hecht, M. H.; Kapit, J.; Quinn, R. C.; Catling, D. C.; Clark, B. C.; Ming, D. W.; Gospodinova, K.; Hredzak, P.; McElhoney, K.; hide

    2010-01-01

    Over the past several decades, elemental sulfur in martian soils and rocks has been detected by a number of missions using X-ray spectroscopy [1-3]. Optical spectroscopy has also provided evidence for widespread sulfates on Mars [4,5]. The ubiquitous presence of sulfur in soils has been interpreted as a widely distributed sulfate mineralogy [6]. However, direct confirmation as to the identity and solubility of the sulfur species in martian soil has never been obtained. One goal of the Wet Chemistry Laboratory (WCL) [7] on board the 2007 Phoenix Mars Lander [8] was to determine soluble sulfate in the martian soil. The WCL received three primary samples. Each sample was added to 25 mL of leaching solution and analysed for solvated ionic species, pH, and conductivity [9,10]. The analysis also showed a discrepancy between charge balance, ionic strength, and conductivity, suggesting unidentified anionic species.

  8. Heating Water with Solar Energy Costs Less at the Phoenix Federal Correctional Institution

    None

    2004-09-01

    A large solar thermal system installed at the Phoenix Federal Correctional Institution (FCI) in 1998 heats water for the prison and costs less than buying electricity to heat that water. This renewable energy system provides 70% of the facility's annual hot water needs. The Federal Bureau of Prisons did not incur the up-front cost of this system because it was financed through an Energy Savings Performance Contract (ESPC). The ESPC payments are 10% less than the energy savings so that the prison saves an average of $6,700 per year, providing an immediate payback. The solar hot water system produces up to 50,000 gallons of hot water daily, enough to meet the needs of 1,250 inmates and staff who use the kitchen, shower, and laundry facilities. This publication details specifications of the parabolic trough solar system and highlights 5 years of measured performance data.

  9. Heating Water with Solar Energy Costs Less at the Phoenix Federal Correctional Institution

    2004-09-01

    A large solar thermal system installed at the Phoenix Federal Correctional Institution (FCI) in 1998 heats water for the prison and costs less than buying electricity to heat that water. This renewable energy system provides 70% of the facility's annual hot water needs. The Federal Bureau of Prisons did not incur the up-front cost of this system because it was financed through an Energy Savings Performance Contract (ESPC). The ESPC payments are 10% less than the energy savings so that the prison saves an average of$6,700 per year, providing an immediate payback. The solar hot water system produces up to 50,000 gallons of hot water daily, enough to meet the needs of 1,250 inmates and staff who use the kitchen, shower, and laundry facilities.

  10. ESTSS at 20 years: "a phoenix gently rising from a lava flow of European trauma".

    Orner, Roderick J

    2013-01-01

    Roderick J. Ørner, who was President between 1997 and 1999, traces the phoenix-like origins of the European Society for Traumatic Stress Studies (ESTSS) from an informal business meeting called during the 1st European Conference on Traumatic Stress (ECOTS) in 1987 to its emergence into a formally constituted society. He dwells on the challenges of tendering a trauma society within a continent where trauma has been and remains endemic. ESTSS successes are noted along with a number of personal reflections on activities that give rise to concern for the present as well as its future prospects. Denial of survivors' experiences and turning away from survivors' narratives by reframing their experiences to accommodate helpers' theory-driven imperatives are viewed with alarm. Arguments are presented for making human rights, memory, and ethics core elements of a distinctive European psycho traumatology, which will secure current ESTSS viability and future integrity.

  11. Autopsy on a dead spreading center: The Phoenix Ridge, Drake Passage, Antarctica

    Livermore, Roy; Balanyá, Juan Carlos; Maldonado, Andrés; Martínez, José Miguel; Rodríguez-Fernández, José; Sanz de Galdeano, Carlos; Galindo Zaldívar, Jesús; Jabaloy, Antonio; Barnolas, Antonio; Somoza, Luis; Hernández-Molina, Javier; Suriñach, Emma; Viseras, César

    2000-07-01

    New bathymetric and magnetic anomaly data from the Phoenix Ridge, Antarctica, show that extinction of all three remaining segments occurred at the time of magnetic chron C2A (3.3 ± 0.2 Ma), synchronous with a ridge-trench collision south of the Hero Fracture Zone. This implies that the ultimate cause of extinction was a change in plate boundary forces occasioned by this collision. Spreading rates slowed abruptly at the time of chron C4 (7.8 ± 0.3 Ma), probably as a result of extinction of the West Scotia Ridge, which would have led to an increase in slip rate and transpressional stress across the Shackleton Fracture Zone. Spectacular, high-relief ridges flanking the extinct spreading center, mapped for the first time using multibeam swath bathymetry, are interpreted as a consequence of a reduction in spreading rate, involving a temporary magma oversupply immediately prior to extinction.

  12. Phoenix dactylifera L. leaf extract phytosynthesized gold nanoparticles; controlled synthesis and catalytic activity

    Zayed, Mervat F.; Eisa, Wael H.

    2014-03-01

    A green synthesis route was reported to explore the reducing and capping potential of Phoenix dactylifera extract for the synthesis of gold nanoparticles. The processes of nucleation and growth of gold nanoparticles were followed by monitoring the absorption spectra during the reaction. The size and morphology of these nanoparticles was typically imaged using transmission electron microscopy (TEM). The particle size ranged between 32 and 45 nm and are spherical in shape. Fourier transform infrared (FTIR) analysis suggests that the synthesized gold nanoparticles might be stabilized through the interactions of hydroxyl and carbonyl groups in the carbohydrates, flavonoids, tannins and phenolic acids present in P. dactylifera. The as-synthesized Au colloids exhibited good catalytic activity for the degradation of 4-nitrophenol.

  13. Reconciling the Differences between the Measurements of CO2 Isotopes by the Phoenix and MSL Landers

    Niles, P. B.; Mahaffy, P. R.; Atreya, S.; Pavlov, A. A.; Trainer, M.; Webster, C. R.; Wong, M.

    2014-01-01

    Precise stable isotope measurements of the CO2 in the martian atmosphere have the potential to provide important constraints for our understanding of the history of volatiles, the carbon cycle, current atmospheric processes, and the degree of water/rock interaction on Mars. There have been several different measurements by landers and Earth based systems performed in recent years that have not been in agreement. In particular, measurements of the isotopic composition of martian atmospheric CO2 by the Thermal and Evolved Gas Analyzer (TEGA) instrument on the Mars Phoenix Lander and the Sample Analysis at Mars (SAM) instrument on the Mars Science Laboratory (MSL) are in stark disagreement. This work attempts to use measurements of mass 45 and mass 46 of martian atmospheric CO2 by the SAM and TEGA instruments to search for agreement as a first step towards reaching a consensus measurement that might be supported by data from both instruments.

  14. The Phoenix Physician: defining a pathway toward leadership in patient-centered care.

    Good, Robert G; Bulger, John B; Hasty, Robert T; Hubbard, Kevin P; Schwartz, Elliott R; Sutton, John R; Troutman, Monte E; Nelinson, Donald S

    2012-08-01

    Health care delivery has evolved in reaction to scientific and technological discoveries, emergent patient needs, and market forces. A current focus on patient-centered care has pointed to the need for the reallocation of resources to improve access to and delivery of efficient, cost-effective, quality care. In response to this need, primary care physicians will find themselves in a new role as team leader. The American College of Osteopathic Internists has developed the Phoenix Physician, a training program that will prepare primary care residents and practicing physicians for the changes in health care delivery and provide them with skills such as understanding the contributions of all team members (including an empowered and educated patient), evaluating and treating patients, and applying performance metrics and information technology to measure and improve patient care and satisfaction. Through the program, physicians will also develop personal leadership and communication skills.

  15. Friction stir welded AM50 and AZ31 Mg alloys: Microstructural evolution and improved corrosion resistance

    Templeman, Yael [Department of Materials Engineering, Ben Gurion University of the Negev, PO Box 653, Beer Sheva 84105 (Israel); Ben Hamu, Guy [Department of Mechanical Engineering, Sami Shamoon College of Engineering, Ashdod 77245 (Israel); Meshi, Louisa, E-mail: Louisa@bgu.ac.il [Department of Materials Engineering, Ben Gurion University of the Negev, PO Box 653, Beer Sheva 84105 (Israel)

    2017-04-15

    One of the major drawbacks of Mg alloys is poor weldability, caused by porosity formation during conventional fusion welding processes. Friction Stir Welding (FSW) is promising technique in this context since it is a solid state technique. Contradicting results were published in the literature regarding the FSWed Mg alloys joint's properties. Current research was performed in order to investigate the microstructure and corrosion properties of FSWed Mg alloys, studying representatives of two commercial families: wrought AZ31-H24 and die cast AM50. It was found that in both alloys recrystallization occurred during the FSW. In AM50 the mechanism of the recrystallization was continuous, manifested by dislocation rearrangement into sub grain boundaries. In AZ31 discontinuous recrystallization had occurred through grain boundaries migration - twins rotated with respect to the matrix, turning into low angle grain boundaries. Corrosion resistance has improved during the FSW in both alloys to different extents. In the AM50 alloy, the nugget exhibited significantly higher surface potential than the base metal mainly due to the higher Al concentration in the matrix of the nugget, resulting from the dissolution of Al-enrichment and β-Mg{sub 17}Al{sub 12} phase. In the AZ31 alloy, no change in Al concentration had occurred, and the surface potential measured in the nugget was only slightly higher than in the base metal. These results underline the appropriateness of the FSW for Mg alloys since during the conventional welding deterioration of the corrosion resistance occurs. - Highlights: • Following FSW, AZ31-H24 experienced discontinuous recrystallization. • In AZ31 grain boundaries migration occurred, thus twins rotated. • In die cast AM50 continuous recrystallization occurred during the FSW. • In AM50 - dislocations rearranged into sub grain boundaries. • Corrosion resistance has improved during the FSW in both alloys to different extent.

  16. Friction stir welded AM50 and AZ31 Mg alloys: Microstructural evolution and improved corrosion resistance

    Templeman, Yael; Ben Hamu, Guy; Meshi, Louisa

    2017-01-01

    One of the major drawbacks of Mg alloys is poor weldability, caused by porosity formation during conventional fusion welding processes. Friction Stir Welding (FSW) is promising technique in this context since it is a solid state technique. Contradicting results were published in the literature regarding the FSWed Mg alloys joint's properties. Current research was performed in order to investigate the microstructure and corrosion properties of FSWed Mg alloys, studying representatives of two commercial families: wrought AZ31-H24 and die cast AM50. It was found that in both alloys recrystallization occurred during the FSW. In AM50 the mechanism of the recrystallization was continuous, manifested by dislocation rearrangement into sub grain boundaries. In AZ31 discontinuous recrystallization had occurred through grain boundaries migration - twins rotated with respect to the matrix, turning into low angle grain boundaries. Corrosion resistance has improved during the FSW in both alloys to different extents. In the AM50 alloy, the nugget exhibited significantly higher surface potential than the base metal mainly due to the higher Al concentration in the matrix of the nugget, resulting from the dissolution of Al-enrichment and β-Mg 17 Al 12 phase. In the AZ31 alloy, no change in Al concentration had occurred, and the surface potential measured in the nugget was only slightly higher than in the base metal. These results underline the appropriateness of the FSW for Mg alloys since during the conventional welding deterioration of the corrosion resistance occurs. - Highlights: • Following FSW, AZ31-H24 experienced discontinuous recrystallization. • In AZ31 grain boundaries migration occurred, thus twins rotated. • In die cast AM50 continuous recrystallization occurred during the FSW. • In AM50 - dislocations rearranged into sub grain boundaries. • Corrosion resistance has improved during the FSW in both alloys to different extent.

  17. Tank 241-AZ-101 criticality assessment resulting from pump jet mixing: Sludge mixing simulation

    Onishi, Y.; Recknagle, K.

    1997-04-01

    Tank 241-AZ-101 (AZ-101) is one of 28 double-shell tanks located in the AZ farm in the Hanford Site`s 200 East Area. The tank contains a significant quantity of fissile materials, including an estimated 9.782 kg of plutonium. Before beginning jet pump mixing for mitigative purposes, the operations must be evaluated to demonstrate that they will be subcritical under both normal and credible abnormal conditions. The main objective of this study was to address a concern about whether two 300-hp pumps with four rotating 18.3-m/s (60-ft/s) jets can concentrate plutonium in their pump housings during mixer pump operation and cause a criticality. The three-dimensional simulation was performed with the time-varying TEMPEST code to determine how much the pump jet mixing of Tank AZ-101 will concentrate plutonium in the pump housing. The AZ-101 model predicted that the total amount of plutonium within the pump housing peaks at 75 g at 10 simulation seconds and decreases to less than 10 g at four minutes. The plutonium concentration in the entire pump housing peaks at 0.60 g/L at 10 simulation seconds and is reduced to below 0.1 g/L after four minutes. Since the minimum critical concentration of plutonium is 2.6 g/L, and the minimum critical plutonium mass under idealized plutonium-water conditions is 520 g, these predicted maximums in the pump housing are much lower than the minimum plutonium conditions needed to reach a criticality level. The initial plutonium maximum of 1.88 g/L still results in safety factor of 4.3 in the pump housing during the pump jet mixing operation.

  18. Tank 241-AZ-101 criticality assessment resulting from pump jet mixing: Sludge mixing simulation

    Onishi, Y.; Recknagle, K.

    1997-04-01

    Tank 241-AZ-101 (AZ-101) is one of 28 double-shell tanks located in the AZ farm in the Hanford Site's 200 East Area. The tank contains a significant quantity of fissile materials, including an estimated 9.782 kg of plutonium. Before beginning jet pump mixing for mitigative purposes, the operations must be evaluated to demonstrate that they will be subcritical under both normal and credible abnormal conditions. The main objective of this study was to address a concern about whether two 300-hp pumps with four rotating 18.3-m/s (60-ft/s) jets can concentrate plutonium in their pump housings during mixer pump operation and cause a criticality. The three-dimensional simulation was performed with the time-varying TEMPEST code to determine how much the pump jet mixing of Tank AZ-101 will concentrate plutonium in the pump housing. The AZ-101 model predicted that the total amount of plutonium within the pump housing peaks at 75 g at 10 simulation seconds and decreases to less than 10 g at four minutes. The plutonium concentration in the entire pump housing peaks at 0.60 g/L at 10 simulation seconds and is reduced to below 0.1 g/L after four minutes. Since the minimum critical concentration of plutonium is 2.6 g/L, and the minimum critical plutonium mass under idealized plutonium-water conditions is 520 g, these predicted maximums in the pump housing are much lower than the minimum plutonium conditions needed to reach a criticality level. The initial plutonium maximum of 1.88 g/L still results in safety factor of 4.3 in the pump housing during the pump jet mixing operation

  19. Learning from Balance Sheet Visualization

    Tanlamai, Uthai; Soongswang, Oranuj

    2011-01-01

    This exploratory study examines alternative visuals and their effect on the level of learning of balance sheet users. Executive and regular classes of graduate students majoring in information technology in business were asked to evaluate the extent of acceptance and enhanced capability of these alternative visuals toward their learning…

  20. Off-Balance Sheet Financing.

    Adams, Matthew C.

    1998-01-01

    Examines off-balance sheet financing, the facilities use of outsourcing for selected needs, as a means of saving operational costs and using facility assets efficiently. Examples of using outside sources for energy supply and food services, as well as partnering with business for facility expansion are provided. Concluding comments address tax…

  1. Characterization of the first core sample of neutralized current acid waste from double-shell tank 101-AZ

    Peterson, M.E.; Scheele, R.D.; Tingey, J.M.

    1989-09-01

    In FY 1989, Westinghouse Hanford Company (WHC) successfully obtained four core samples (totaling seven segments) of neutralized current acid waste (NCAW) from double-shell tanks (DSTs) 101-AZ and 102-AZ. A segment was a 19-in.-long and 1-in.-diameter cylindrical sample of waste. A core sample consisted of enough 19-in.-long segments to obtain the waste of interest. Three core samples were obtained from DST 101-AZ and one core sample from DST 102-AZ. Two DST 101-AZ core samples consisted of two segments per core, and the third core sample consisted of only one segment. The third core consisted of the solids from the bottom of the tank and was used to determine the relative abrasiveness of this NCAW. The DST 102-AZ core sample consisted of two segments. The core samples were transported to the Pacific Northwest Laboratory (PNL), where the waste was extruded from its sampler and extensively characterized. A characterization plan was followed that simulated the processing of the NCAW samples through retrieval, pretreatment and vitrification process steps. Physical, rheological, chemical and radiochemical properties were measured throughout the process steps. The characterization of the first core sample from DST 101-AZ was completed, and the results are provided in this report. The results for the other core characterizations will be reported in future reports. 3 refs., 13 figs., 10 tabs

  2. An intensive two-week study of an urban CO2 dome in Phoenix, Arizona, USA

    Idso, C.D.; Balling, R.C. Jr.

    2001-01-01

    Atmospheric CO 2 concentrations were measured prior to dawn and in the middle of the afternoon at a height of 2m above the ground along four transects through the metropolitan area of Phoenix, Arizona on 14 consecutive days in January 2000. The data revealed the existence of a strong but variable urban CO 2 dome, which at one time exhibited a peak CO 2 concentration at the center of the city that was 75% greater than that of the surrounding rural area. Mean city-center peak enhancements, however, were considerably lower, averaging 43% on weekdays and 38% on weekends; and averaged over the entire commercial sector of the city, they were lower still, registering 30% on weekdays and 23% on weekends. Over the surrounding residential areas, on the other hand, there are no weekday-weekend differences in boundary-layer CO 2 concentration. Furthermore, because of enhanced vertical mixing during the day, near-surface CO 2 concentrations in the afternoon are typically reduced from what they are prior to sunrise. This situation is additionally perturbed by the prevailing southwest-to-northeast flow of air at that time of day, which lowers afternoon CO 2 concentrations on the southern and western edges of the city still more, as a consequence of the importation of pristine rural air. The southwest-to-northeast flow of air also sometimes totally compensates for the afternoon vertical-mixing-induced loss of CO 2 from areas on the northern and eastern sides of the city, as a consequence of the northeastward advection of CO 2 emanating from the central, southern and western sectors of the city. Hence, although complex, the nature of the urban CO 2 dome of Phoenix, Arizona, is readily understandable in terms of basic meteorological phenomena and their interaction with human activities occurring at the land/air interface. (Author)

  3. Chemical Composition of Date Palm (Phoenix dactylifera L.) Seed Oil from Six Saudi Arabian Cultivars.

    Nehdi, Imeddedine Arbi; Sbihi, Hassen Mohamed; Tan, Chin Ping; Rashid, Umer; Al-Resayes, Saud Ibrahim

    2018-03-01

    This investigation aimed to evaluate the chemical composition and physicochemical properties of seed oils from 6 date palm (Phoenix. dactylifera L.) cultivars (Barhi, Khalas, Manifi, Rezeiz, Sulaj, and Sukkari) growing in Saudi Arabia and to compare them with conventional palm olein. The mean oil content of the seeds was about 7%. Oleic acid (48.67%) was the main fatty acid, followed by lauric acid (17.26%), stearic acid (10.74%), palmitic acid (9.88%), and linolenic acid (8.13%). The mean value for free fatty acids content was 0.5%. The P. dactylifera seed oil also exhibited a mean tocol content of 70.75 mg/100 g. α-Tocotrienol was the most abundant isomer (30.19%), followed by γ-tocopherol (23.61%), γ-tocotrienol (19.07%), and α-tocopherol (17.52%). The oils showed high thermal and oxidative stabilities. The findings indicate that date seed oil has the potential to be used in the food industry as an abundant alternative to palm olein. This study showed that date seed had great nutritional value due to which it can be used for food applications especially as frying or cooking oil. In addition, date oil has also potential to be used in cosmetic and pharmaceutical practices as well. The extraction of oil from Phoenix dactylifera seed on large scale can create positive socioeconomic benefits especially for rural communities and could also assist to resolve the environmental issues generated by excess date production in large scale date-producing countries such as Saudi Arabia. © 2018 Institute of Food Technologists®.

  4. Thermal and Evolved Gas Behavior of Calcite Under Mars Phoenix TEGA Operating Conditions

    Ming, D.W.; Niles, P.B.; Morris, R.V.; Boynton, W.V.; Golden, D.C.; Lauer, H.V.; Sutter, B.

    2009-01-01

    The Mars Phoenix Scout Mission with its diverse instrument suite successfully examined several soils on the Northern plains of Mars. The Thermal and Evolved Gas Analyzer (TEGA) was employed to detect organic and inorganic materials by coupling a differential scanning calorimeter (DSC) with a magnetic-sector mass spectrometer (MS). Martian soil was heated up to 1000 C in the DSC ovens and evolved gases from mineral decomposition products were examined with the MS. TEGA s DSC has the capability to detect endothermic and exothermic reactions during heating that are characteristic of minerals present in the Martian soil. Initial TEGA results indicated the presence of endothermic peaks with onset temperatures that ranged from 675 C to 750 C with corresponding CO2 release. This result suggests the presence of calcite (CaCO3. CaO + CO2). Organic combustion to CO2 is not likely since this mostly occurs at temperatures below 550 C. Fe-carbonate and Mg-carbonate are not likely because their decomposition temperatures are less than 600 C. TEGA enthalpy determinations suggest that calcite, may occur in the Martian soil in concentrations of approx.1 to 5 wt. %. The detection of calcite could be questioned based on previous results that suggest Mars soils are mostly acidic. However, the Phoenix landing site soil pH was measured at pH 8.3 0.5, which is typical of terrestrial soils where pH is controlled by calcite solubility. The range of onset temperatures and calcite concentration as calculated by TEGA is poorly con-strained in part because of limited thermal data of cal-cite at reduced pressures. TEGA operates at calcite literature thermal data was obtained at 1000 mbar or higher pressures.

  5. Outreach Opportunities for Early Career Scientists at the Phoenix ComiCon

    Horodyskyj, L.; Walker, S. I.; Forrester, J. H.

    2014-12-01

    The Phoenix ComiCon (PCC) is a rapidly growing annual four-day pop culture event, featuring guests, costuming, exhibits, and discussion panels for popular sci-fi, fantasy, horror, and anime franchises. In 2013, PCC began experimenting with science discussion panels. The popularity of the science programming resulted in an expansion of the track for 2014, which Horodyskyj was responsible for coordinating. Thirty hours of programming were scheduled, including 25 discussion panels, NASA's FameLab, and a Mars room. Panelists included industry specialists, established scientists, STEM outreach enthusiasts, and early career scientists. The majority of the panelists were early career scientists recruited from planetary sciences and biology departments at ASU and UA. Panel topics included cosmology, biotechnology, artificial intelligence, space exploration, astrobiology, and the cross-linkages of each with pop culture. Formats consisted of Q&A, presentations, and interactive game shows. Although most panels were aimed at the general audience, some panels were more specialized. PCC 2014 attracted 77,818 attendees. The science programming received rave reviews from the audience, the PCC management, and the panelists themselves. Many panel rooms were filled to capacity and required crowd control to limit attendance. We observed the formation of science "groupies" who sought out the science panels exclusively and requested more information on other science public events in the Phoenix area. We distributed surveys to several select sessions to evaluate audience reasons for attending the science panels and their opinion of the scientists they observed. We will present the results of these surveys. As the PCC continues to grow at an exponential rate, the science programming will continue to expand. We will discuss ideas for continued expansion of the PCC science programming both to serve the public and as a unique public outreach opportunity for early career scientists.

  6. Parallel implementation of the PHOENIX generalized stellar atmosphere program. II. Wavelength parallelization

    Baron, E.; Hauschildt, Peter H.

    1998-01-01

    We describe an important addition to the parallel implementation of our generalized nonlocal thermodynamic equilibrium (NLTE) stellar atmosphere and radiative transfer computer program PHOENIX. In a previous paper in this series we described data and task parallel algorithms we have developed for radiative transfer, spectral line opacity, and NLTE opacity and rate calculations. These algorithms divided the work spatially or by spectral lines, that is, distributing the radial zones, individual spectral lines, or characteristic rays among different processors and employ, in addition, task parallelism for logically independent functions (such as atomic and molecular line opacities). For finite, monotonic velocity fields, the radiative transfer equation is an initial value problem in wavelength, and hence each wavelength point depends upon the previous one. However, for sophisticated NLTE models of both static and moving atmospheres needed to accurately describe, e.g., novae and supernovae, the number of wavelength points is very large (200,000 - 300,000) and hence parallelization over wavelength can lead both to considerable speedup in calculation time and the ability to make use of the aggregate memory available on massively parallel supercomputers. Here, we describe an implementation of a pipelined design for the wavelength parallelization of PHOENIX, where the necessary data from the processor working on a previous wavelength point is sent to the processor working on the succeeding wavelength point as soon as it is known. Our implementation uses a MIMD design based on a relatively small number of standard message passing interface (MPI) library calls and is fully portable between serial and parallel computers. copyright 1998 The American Astronomical Society

  7. The Hydro-Economic Interdependency of Cities: Virtual Water Connections of the Phoenix, Arizona Metropolitan Area

    Richard R. Rushforth

    2015-06-01

    Full Text Available Water footprinting has revealed hydro-economic interdependencies between distant global geographies via trade, especially of agricultural and manufactured goods. However, for metropolitan areas, trade not only entails commodity flows at many scales from intra-municipal to global, but also substantial intra-metropolitan flows of the skilled labor that is essential to a city’s high-value economy. Virtual water flows between municipalities are directly relevant for municipal water supply policy and infrastructure investment because they quantify the hydro-economic dependency between neighboring municipalities. These municipalities share a physical water supply and also place demands on their neighbors’ water supplies by outsourcing labor and commodity production outside the municipal and water supply system boundary to the metropolitan area. Metropolitan area communities span dense urban cores to fringe agricultural towns, spanning a wide range of the US hydro-economy. This study quantifies water footprints and virtual water flows of the complete economy of the Phoenix Metropolitan Area’s municipalities. A novel approach utilized journey to work data to estimate virtual water flows embedded in labor. Commodities dominate virtual water flows at all scales of analysis, however labor is shown to be important for intra-metropolitan virtual water flows. This is the first detailed water footprint analysis of Phoenix, an important city in a water-scarce region. This study establishes a hydro-economic typology for communities to define several niche roles and decision making points of view. This study’s findings can be used to classify communities with respect to their relative roles, and to benchmark future improvements in water sustainability for all types of communities. More importantly, these findings motivate cooperative approaches to intra-metropolitan water supply policy that recognize the hydro-economic interdependence of these

  8. Characterization of hydrogen peroxide-resistant Acinetobacter species isolated during the Mars Phoenix spacecraft assembly.

    Derecho, I; McCoy, K B; Vaishampayan, P; Venkateswaran, K; Mogul, R

    2014-10-01

    The microbiological inventory of spacecraft and the associated assembly facility surfaces represent the primary pool of forward contaminants that may impact the integrity of life-detection missions. Herein, we report on the characterization of several strains of hydrogen peroxide-resistant Acinetobacter, which were isolated during the Mars Phoenix lander assembly. All Phoenix-associated Acinetobacter strains possessed very high catalase specific activities, and the specific strain, A. gyllenbergii 2P01AA, displayed a survival against hydrogen peroxide (no loss in 100 mM H2O2 for 1 h) that is perhaps the highest known among Gram-negative and non-spore-forming bacteria. Proteomic characterizations reveal a survival mechanism inclusive of proteins coupled to peroxide degradation (catalase and alkyl hydroperoxide reductase), energy/redox management (dihydrolipoamide dehydrogenase), protein synthesis/folding (EF-G, EF-Ts, peptidyl-tRNA hydrolase, DnaK), membrane functions (OmpA-like protein and ABC transporter-related protein), and nucleotide metabolism (HIT family hydrolase). Together, these survivability and biochemical parameters support the hypothesis that oxidative tolerance and the related biochemical features are the measurable phenotypes or outcomes for microbial survival in the spacecraft assembly facilities, where the low-humidity (desiccation) and clean (low-nutrient) conditions may serve as selective pressures. Hence, the spacecraft-associated Acinetobacter, due to the conferred oxidative tolerances, may ultimately hinder efforts to reduce spacecraft bioburden when using chemical sterilants, thus suggesting that non-spore-forming bacteria may need to be included in the bioburden accounting for future life-detection missions.

  9. Phoenix – A model-based Human Reliability Analysis methodology: Qualitative Analysis Procedure

    Ekanem, Nsimah J.; Mosleh, Ali; Shen, Song-Hua

    2016-01-01

    Phoenix method is an attempt to address various issues in the field of Human Reliability Analysis (HRA). Built on a cognitive human response model, Phoenix incorporates strong elements of current HRA good practices, leverages lessons learned from empirical studies, and takes advantage of the best features of existing and emerging HRA methods. Its original framework was introduced in previous publications. This paper reports on the completed methodology, summarizing the steps and techniques of its qualitative analysis phase. The methodology introduces the “Crew Response Tree” which provides a structure for capturing the context associated with Human Failure Events (HFEs), including errors of omission and commission. It also uses a team-centered version of the Information, Decision and Action cognitive model and “macro-cognitive” abstractions of crew behavior, as well as relevant findings from cognitive psychology literature and operating experience, to identify potential causes of failures and influencing factors during procedure-driven and knowledge-supported crew-plant interactions. The result is the set of identified HFEs and likely scenarios leading to each. The methodology itself is generic in the sense that it is compatible with various quantification methods, and can be adapted for use across different environments including nuclear, oil and gas, aerospace, aviation, and healthcare. - Highlights: • Produces a detailed, consistent, traceable, reproducible and properly documented HRA. • Uses “Crew Response Tree” to capture context associated with Human Failure Events. • Models dependencies between Human Failure Events and influencing factors. • Provides a human performance model for relating context to performance. • Provides a framework for relating Crew Failure Modes to its influencing factors.

  10. Whooping Cough (Pertussis) - Fact Sheet for Parents

    ... months 4 through 6 years Fact Sheet for Parents Color [2 pages] Español: Tosferina (pertussis) The best ... according to the recommended schedule. Fact Sheets for Parents Diseases and the Vaccines that Prevent Them Chickenpox ...

  11. Análisis del perfil de azúcares en la autentificación de zumos de frutas

    Úbeda Gallego, Ana

    2013-01-01

    El objetivo general ha sido estudiar el perfil de azúcares por HPAEC-PAD para la autentificación de zumos de frutas de naranja, manzana y piña. Este objetivo general se ha dividido en los siguientes objetivos parciales: 1. Optimizar el método de análisis de azúcares por HPAEC-PAD. Para ello se han ensayado distintas concentraciones de NaOH en la fase móvil y distinta velocidad de flujo. Se han analizando muestras de azúcares, zumos concentrados y zumos comerciales. 2. Determinar el p...

  12. 21 CFR 880.5180 - Burn sheet.

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Burn sheet. 880.5180 Section 880.5180 Food and... Burn sheet. (a) Identification. A burn sheet is a device made of a porous material that is wrapped aroung a burn victim to retain body heat, to absorb wound exudate, and to serve as a barrier against...

  13. Manifold free multiple sheet superplastic forming

    Elmer, John W.; Bridges, Robert L.

    2004-01-13

    Fluid-forming compositions in a container attached to enclosed adjacent sheets are heated to relatively high temperatures to generate fluids (gases) that effect inflation of the sheets. Fluid rates to the enclosed space between the sheets can be regulated by the canal from the container. Inflated articles can be produced by a continuous, rather than batch-type, process.

  14. On the possible eigenoscillations of neutral sheets

    Almeida, W.A.; Costa, J.M. da; Aruquipa, E.G.; Sudano, J.P.

    1974-12-01

    A neutral sheet model with hyperbolic tangent equilibrium magnetic field and hyperbolic square secant density profiles is considered. It is shown that the equation for small oscillations takes the form of an eigenvalue oscillation problem. Computed eigenfrequencies of the geomagnetic neutral sheet were found to be in the range of the resonant frequencies of the geomagnetic plasma sheet computed by other authors

  15. Bioetanol de la caña de azúcar

    N. Aguilar-Rivera

    2007-01-01

    Full Text Available La búsqueda de la viabilidad y desarrollo de la agroindustria de la caña de azúcar es ya una política imperativa. La producción de caña y azúcar constituyen la principal agroindustria del país, con presencia en 57 ingenios azucareros, localizados en 15 estados de la república. Sin embargo, la actual ineficiencia productiva, altos costos y otras causas —como la entrada de jarabe de maíz de alta fructosa (HFCS de menor costo— han desplazado el consumo interno de azúcar de caña, principalmente en bebidas embotelladas. Todos estos factores han contribuido a la actual y prolongada crisis del sector azucarero. Por lo tanto, la industria debe reestructurarse y reducir la producción de azúcar hacia la competitividad, con la alternativa del etanol combustible en la búsqueda de un futuro para la industria azucarera en México. Con la producción de etanol (EtOH a gran escala, por parte de los ingenios azucareros, es posible visualizar un nuevo y futuro mercado de uso de energías renovables en México, oportunidades para la exportación e incrementar los beneficios ambientales y económicos a través de su uso. La flexibilidad de la producción combinada, de azúcar y etanol en los ingenios, permitirá alcanzar esquemas y objetivos ambientales como nación. Para la industria azucarera, su mayor competidesafío, en este sentido, representa disminuir los costos actuales de producción de etanol a través del uso de la ingeniería genética, uso de diferentes materias primas y la totalidad de la planta de caña de azúcar e introducir mejoras tecnológicas.

  16. Desarrollo de las pequeñas industrias rurales de la caña de azúcar en iberoamerica: Melaza, Panela y Azúcar Moreno

    Da Silva, Fabio César; Cesar, Marco; Hernández Díaz-Ambrona, Carlos Gregorio

    2010-01-01

    Los niveles de producción de azúcar en los últimos años crecen a un ritmo semejante al crecimiento poblacional. El fabricante debe estar atento a las características de calidad del producto que su mercado o comprador/consumidor exige y la facilidad de transporte al centro consumidor. La legislación debe especificar los requisitos mínimos pero el fabricante debe tener como desafío ofrecer un producto de calidad y reducir los riesgos ambientales en sus cultivos en función de la aptitud de la...

  17. Geometry of thin liquid sheet flows

    Chubb, Donald L.; Calfo, Frederick D.; Mcconley, Marc W.; Mcmaster, Matthew S.; Afjeh, Abdollah A.

    1994-01-01

    Incompresible, thin sheet flows have been of research interest for many years. Those studies were mainly concerned with the stability of the flow in a surrounding gas. Squire was the first to carry out a linear, invicid stability analysis of sheet flow in air and compare the results with experiment. Dombrowski and Fraser did an experimental study of the disintegration of sheet flows using several viscous liquids. They also detected the formulation of holes in their sheet flows. Hagerty and Shea carried out an inviscid stability analysis and calculated growth rates with experimental values. They compared their calculated growth rates with experimental values. Taylor studied extensively the stability of thin liquid sheets both theoretically and experimentally. He showed that thin sheets in a vacuum are stable. Brown experimentally investigated thin liquid sheet flows as a method of application of thin films. Clark and Dumbrowski carried out second-order stability analysis for invicid sheet flows. Lin introduced viscosity into the linear stability analysis of thin sheet flows in a vacuum. Mansour and Chigier conducted an experimental study of the breakup of a sheet flow surrounded by high-speed air. Lin et al. did a linear stability analysis that included viscosity and a surrounding gas. Rangel and Sirignano carried out both a linear and nonlinear invisid stability analysis that applies for any density ratio between the sheet liquid and the surrounding gas. Now there is renewed interest in sheet flows because of their possible application as low mass radiating surfaces. The objective of this study is to investigate the fluid dynamics of sheet flows that are of interest for a space radiator system. Analytical expressions that govern the sheet geometry are compared with experimental results. Since a space radiator will operate in a vacuum, the analysis does not include any drag force on the sheet flow.

  18. Ice sheet hydrology from observations

    Jansson, Peter [Dept. of Physical Geography and Quaternary Geology, Stockholm Univ-, Stockholm (Sweden)

    2010-11-15

    The hydrological systems of ice sheets are complex. Our view of the system is split, largely due to the complexity of observing the systems. Our basic knowledge of processes have been obtained from smaller glaciers and although applicable in general to the larger scales of the ice sheets, ice sheets contain features not observable on smaller glaciers due to their size. The generation of water on the ice sheet surface is well understood and can be satisfactorily modeled. The routing of water from the surface down through the ice is not complicated in terms of procat has been problematic is the way in which the couplings between surface and bed has been accomplished through a kilometer of cold ice, but with the studies on crack propagation and lake drainage on Greenland we are beginning to understand also this process and we know water can be routed through thick cold ice. Water generation at the bed is also well understood but the main problem preventing realistic estimates of water generation is lack of detailed information about geothermal heat fluxes and their geographical distribution beneath the ice. Although some average value for geothermal heat flux may suffice, for many purposes it is important that such values are not applied to sub-regions of significantly higher fluxes. Water generated by geothermal heat constitutes a constant supply and will likely maintain a steady system beneath the ice sheet. Such a system may include subglacial lakes as steady features and reconfiguration of the system is tied to time scales on which the ice sheet geometry changes so as to change pressure gradients in the basal system itself. Large scale re-organization of subglacial drainage systems have been observed beneath ice streams. The stability of an entirely subglacially fed drainage system may hence be perturbed by rapid ice flow. In the case of Antarctic ice streams where such behavior has been observed, the ice streams are underlain by deformable sediments. It is

  19. Periodic folding of viscous sheets

    Ribe, Neil M.

    2003-09-01

    The periodic folding of a sheet of viscous fluid falling upon a rigid surface is a common fluid mechanical instability that occurs in contexts ranging from food processing to geophysics. Asymptotic thin-layer equations for the combined stretching-bending deformation of a two-dimensional sheet are solved numerically to determine the folding frequency as a function of the sheet’s initial thickness, the pouring speed, the height of fall, and the fluid properties. As the buoyancy increases, the system bifurcates from “forced” folding driven kinematically by fluid extrusion to “free” folding in which viscous resistance to bending is balanced by buoyancy. The systematics of the numerically predicted folding frequency are in good agreement with laboratory experiments.

  20. Ice sheet hydrology from observations

    Jansson, Peter

    2010-11-01

    The hydrological systems of ice sheets are complex. Our view of the system is split, largely due to the complexity of observing the systems. Our basic knowledge of processes have been obtained from smaller glaciers and although applicable in general to the larger scales of the ice sheets, ice sheets contain features not observable on smaller glaciers due to their size. The generation of water on the ice sheet surface is well understood and can be satisfactorily modeled. The routing of water from the surface down through the ice is not complicated in terms of procat has been problematic is the way in which the couplings between surface and bed has been accomplished through a kilometer of cold ice, but with the studies on crack propagation and lake drainage on Greenland we are beginning to understand also this process and we know water can be routed through thick cold ice. Water generation at the bed is also well understood but the main problem preventing realistic estimates of water generation is lack of detailed information about geothermal heat fluxes and their geographical distribution beneath the ice. Although some average value for geothermal heat flux may suffice, for many purposes it is important that such values are not applied to sub-regions of significantly higher fluxes. Water generated by geothermal heat constitutes a constant supply and will likely maintain a steady system beneath the ice sheet. Such a system may include subglacial lakes as steady features and reconfiguration of the system is tied to time scales on which the ice sheet geometry changes so as to change pressure gradients in the basal system itself. Large scale re-organization of subglacial drainage systems have been observed beneath ice streams. The stability of an entirely subglacially fed drainage system may hence be perturbed by rapid ice flow. In the case of Antarctic ice streams where such behavior has been observed, the ice streams are underlain by deformable sediments. It is

  1. Urban effects on regional climate: a case study in the Phoenix and Tucson ‘sun’ corridor

    Zhao Yang,; Francina Dominguez,; Hoshin Gupta,; Xubin Zeng,; Norman, Laura M.

    2016-01-01

    Land use and land cover change (LULCC) due to urban expansion alter the surface albedo, heat capacity, and thermal conductivity of the surface. Consequently, the energy balance in urban regions is different from that of natural surfaces. To evaluate the changes in regional climate that could arise due to projected urbanization in the Phoenix-Tucson corridor, Arizona, we applied the coupled WRF-NOAH-UCM (which includes a detailed urban radiation scheme) to this region. Land cover changes were represented using land cover data for 2005 and projections to 2050, and historical North American Regional Reanalysis (NARR) data were used to specify the lateral boundary conditions. Results suggest that temperature changes will be well defined, reflecting the urban heat island (UHI) effect within areas experiencing LULCC. Changes in precipitation are less robust, but seem to indicate reductions in precipitation over the mountainous regions northeast of Phoenix and decreased evening precipitation over the newly-urbanized area.

  2. Load Test in Sheet Pile

    Luis Orlando Ibanez

    2016-01-01

    In this work, are discussed experiences in the use of mathematical modeling and testing in hydraulic engineering structures. For this purpose the results of load tests in sheet pile, evaluating horizontal and vertical deformations that occur in the same exposed. Comparisons between theoretical methods for calculating deformations and mathematical models based on the Finite Element Method are established. Finally, the coincidence between the numerical model and the results of the load test ful...

  3. AZ-101 Mixer Pump Demonstration Data Acquisition System and Gamma Cart Data Acquisition Control System Software Configuration Management Plan

    WHITE, D.A.

    1999-01-01

    This Software Configuration Management Plan (SCMP) provides the instructions for change control of the AZ1101 Mixer Pump Demonstration Data Acquisition System (DAS) and the Sludge Mobilization Cart (Gamma Cart) Data Acquisition and Control System (DACS)

  4. A biodegradable AZ91 magnesium alloy coated with a thin nanostructured hydroxyapatite for improving the corrosion resistance.

    Mukhametkaliyev, T M; Surmeneva, M A; Vladescu, A; Cotrut, C M; Braic, M; Dinu, M; Vranceanu, M D; Pana, I; Mueller, M; Surmenev, R A

    2017-06-01

    The main aim of this study was to investigate the properties of an AZ91 alloy coated with nanostructured hydroxyapatite (HA) prepared by radio frequency (RF) magnetron sputtering. The bioactivity and biomineralization of the AZ91 magnesium alloy coated with HA were investigated in simulated body fluid (SBF) via an in vitro test. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) analyses were performed. The samples were immersed in SBF to study the ability of the surface to promote the formation of an apatite layer as well as corrosion resistance and mass change of the HA-coated AZ91 alloy. Electrochemical tests were performed to estimate the corrosion behaviour of HA-coated and uncoated samples. The results revealed the capability of the HA coating to significantly improve the corrosion resistance of the uncoated AZ91 alloy. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Ohm's law for a current sheet

    Lyons, L. R.; Speiser, T. W.

    1985-01-01

    The paper derives an Ohm's law for single-particle motion in a current sheet, where the magnetic field reverses in direction across the sheet. The result is considerably different from the resistive Ohm's law often used in MHD studies of the geomagnetic tail. Single-particle analysis is extended to obtain a self-consistency relation for a current sheet which agrees with previous results. The results are applicable to the concept of reconnection in that the electric field parallel to the current is obtained for a one-dimensional current sheet with constant normal magnetic field. Dissipated energy goes directly into accelerating particles within the current sheet.

  6. Effect of gamma radiation on the morphology and Thermophysical properties of the pollen wall of Phoenix dactylifera L.

    El-Ghazaly, Gamal; Kassem, M.E.

    1994-01-01

    Pollen grains of Phoenix dactylifera were exposed to different doses of gamma radiation (250,500,1000 rad and 1 M rad). To access the effect of radiation on the external morphology of the pollen grains, they were examined with SEM after each treatment. In addition the differential thermal analysis technique was used to elucidate the stability of the chemical composition of the pollen wall to gamma radiation. A portion of the treated pollen was- used to pollinate different inflorescences of tw...

  7. In vitro corrosion of pure magnesium and AZ91 alloy?the influence of thin electrolyte layer thickness

    Zeng, Rong-Chang; Qi, Wei-Chen; Zhang, Fen; Li, Shuo-Qi

    2016-01-01

    In vivo degradation predication faces a huge challenge via in vitro corrosion test due to the difficulty for mimicking the complicated microenvironment with various influencing factors. A thin electrolyte layer (TEL) cell for in vitro corrosion of pure magnesium and AZ91 alloy was presented to stimulate the in vivo corrosion in the micro-environment built by the interface of the implant and its neighboring tissue. The results demonstrated that the in vivo corrosion of pure Mg and the AZ91 all...

  8. Experimental formability analysis of bondal sandwich sheet

    Kami, Abdolvahed; Banabic, Dorel

    2018-05-01

    Metal/polymer/metal sandwich sheets have recently attracted the interests of industries like automotive industry. These sandwich sheets have superior properties over single-layer metallic sheets including good sound and vibration damping and light weight. However, the formability of these sandwich sheets should be enhanced which requires more research. In this paper, the formability of Bondal sheet (DC06/viscoelastic polymer/DC06 sandwich sheet) was studied through different types of experiments. The mechanical properties of Bondal were determined by uniaxial tensile tests. Hemispherical punch stretching and hydraulic bulge tests were carried out to determine the forming limit diagram (FLD) of Bondal. Furthermore, cylindrical and square cup drawing tests were performed in dry and oil lubricated conditions. These tests were conducted at different blank holding forces (BHFs). An interesting observation about Bondal sheet deep drawing was obtaining of higher drawing depths at dry condition in comparison with oil-lubricated condition.

  9. Buckling and stretching of thin viscous sheets

    O'Kiely, Doireann; Breward, Chris; Griffiths, Ian; Howell, Peter; Lange, Ulrich

    2016-11-01

    Thin glass sheets are used in smartphone, battery and semiconductor technology, and may be manufactured by producing a relatively thick glass slab and subsequently redrawing it to a required thickness. The resulting sheets commonly possess undesired centerline ripples and thick edges. We present a mathematical model in which a viscous sheet undergoes redraw in the direction of gravity, and show that, in a sufficiently strong gravitational field, buckling is driven by compression in a region near the bottom of the sheet, and limited by viscous resistance to stretching of the sheet. We use asymptotic analysis in the thin-sheet, low-Reynolds-number limit to determine the centerline profile and growth rate of such a viscous sheet.

  10. Start-up physics test predictions for Indian Point 3, cycle 7, utilized PHOENIX-P/ANC

    Powers, M.A.; Buechel, R.J.

    1989-01-01

    The Westinghouse Advanced In-Core Fuel Management System (PHOENIX-P/ANC) was utilized to predict start-up physics test parameters for Indian Point 3 (IP3) cycle 7. This core utilizes a low-leakage loading pattern implementing VANTAGE-5 fuel, which incorporates axial blankets and integral fuel burnable absorbers. Discrete part-length wet annular burnable absorbers (WABAs) are used in some feed assemblies as well. As a measure to reduce vessel fluence, certain peripheral twice-burned assemblies also contain fresh full-length WABAs. The New York Power Authority (NYPA) is using the Westinghouse code system since the methodology was licensed by the U.S. Nuclear Regulatory Commission and because of the user support supplied by Westinghouse. The IP3 cycle 7 PHOENIX-P/ANC model was developed as a joint effort by NYPA and Westinghouse as part of a technology transfer agreement. The PHOENIX-P/ANC model performed very well in start-up physics test predictions and is expected to agree well through cycle depletion. These results have given NYPA further incentive to use the Westinghouse methodology for core follow, loading pattern design determination, and in the safety analysis area

  11. Evaluation of AY/AZ tank farm ventilation system during aging waste retrieval operations

    Wong, J.J.; Waters, E.D.

    1995-01-01

    Waste Management is currently planning to demonstrate mobilization of radioactive waste sludges in Tank 101-AZ beginning in October 1991. The retrieval system being designed will utilize mixer pumps that generate high-velocity, high-volume submerged liquid jets to mobilize settled solids. There is concern that these jets may also generate radioactive aerosols, some of which may be carried into the tank Ventilation system. The purpose of this study is to determine if the current AY/AZ ventilation system or the proposed ventilation system upgrade (Project W-030) will provide adequate deentrainment of liquid and solid aerosols during mixer pump operations, or if the radioactive aerosols will overload the HEPA filters

  12. Effect of alternating voltage treatment on corrosion resistance of AZ91D magnesium alloy

    Liu, X. [Corrosion and Protection Laboratory, Key Laboratory of Superlight Materials and Surface Technology (Harbin Engineering University), Ministry of Education, Harbin (China); Zhang, T.; Shao, Y.; Meng, G.; Wang, F. [Corrosion and Protection Laboratory, Key Laboratory of Superlight Materials and Surface Technology (Harbin Engineering University), Ministry of Education, Harbin (China); State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, Shenyang (China)

    2012-06-15

    AZ91D magnesium alloy was treated by the alternating voltage (AV) treatment technique. The optimal AV-treatment parameters of the alloy were determined by orthogonal experiments. Polarization curve, electrochemical impedance spectroscopy (EIS), and scanning electrochemical microscopy (SECM) were used to understand the effect of AV-treatment on the corrosion resistance of the alloy. AFM, contact angle, and XPS were employed to investigate further the influence of AV-treatment on the properties of the surface film formed on the alloy after AV-treatment. The results showed that a uniform and stable film was formed and the corrosion resistance of AZ91D magnesium alloy was significantly improved after AV-treatment. This was caused by the noticeable change of the chemical structure and semi-conducting properties of the surface film after AV-treatment. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Influence of Zeolite Coating on the Corrosion Resistance of AZ91D Magnesium Alloy

    P. Chakraborty Banerjee

    2014-08-01

    Full Text Available The protective performance of zeolite coating on AZ91D magnesium alloy was evaluated using potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS in 0.1 M sodium chloride solution (NaCl. Electrical equivalent circuit (EEC was developed based upon hypothetical corrosion mechanisms and simulated to correspond to the experimental data. The morphology and the chemical nature of the coating were characterized by scanning electron microscopy (SEM and X-ray diffraction (XRD analysis. Post corrosion morphologies of the zeolite coated and the uncoated AZ91D alloy were investigated using SEM. The corrosion resistance of the zeolite coated specimen was at least one order of magnitude higher than the uncoated specimen.

  14. Project W-314 specific test and evaluation plan for AZ tank farm upgrades

    Hays, W.H.

    1998-01-01

    The purpose of this Specific Test and Evaluation Plan (STEP) is to provide a detailed written plan for the systematic testing of modifications made by the addition of the SN-631 transfer line from the AZ-O1A pit to the AZ-02A pit by the W-314 Project. The STEP develops the outline for test procedures that verify the system's performance to the established Project design criteria. The STEP is a lower tier document based on the W-314 Test and Evaluation P1 an (TEP). Testing includes Validations and Verifications (e.g., Commercial Grade Item Dedication activities, etc), Factory Tests and Inspections (FTIs), installation tests and inspections, Construction Tests and Inspections (CTIs), Acceptance Test Procedures (ATPs), Pre-Operational Test Procedures (POTPs), and Operational Test Procedures (OTPs). The STEP will be utilized in conjunction with the TEP for verification and validation

  15. Diffusion and solubility of Au implanted into the AZ1350 photoresist

    Soares, M.R.F.; Kaschny, J.R.A.; Santos, J.H.R. dos; Amaral, L.; Behar, M.; Fink, D.

    2000-01-01

    In the present paper we report diffusion and solubility results for Au into the photoresist AZ1350. Au was implanted into AZ1350 films at very low energy (E=20 keV) and fluences (PHI=10 12 and 5x10 12 Au/cm 2 ). In this way the radiation damage introduced by the implantation process was minimized and cluster formation was avoided. Annealing was performed in the 150-300 deg. C temperature range and the as implanted and thermal treated samples were analyzed using the Rutherford backscattering (RBS) technique. For the lowest implantation fluence the results have shown a regular atomic diffusion process characterized by an activation energy of E a =640 meV. Instead, for PHI=5x10 12 Au/cm 2 the diffusional mechanism has revealed the effects of the radiation damage. In addition solubility measurements indicate that the solubility limit at 250 deg. C is of the order 0.3 at.%

  16. Corrosion behavior of biodegradable material AZ31 coated with beeswax-colophony resin

    Gumelar, Muhammad Dikdik; Putri, Nur Ajrina; Anggaravidya, Mahendra; Anawati, Anawati

    2018-05-01

    Magnesium (Mg) and its alloys are potential candidates for biodegradable implant materials owing to their ability to degrade spontaneously in a physiological environment. However, the degradation rate is still considered too fast in human body solution. A coating is typically applied to slowdown corrosion rate of Mg alloys. In this work, an organic coating of mixture beeswax-colophony with ratios of 40-60, 50-50, and 60-40 in wt% was synthesized and applied on commercial magnesium alloyAZ31. The coated specimens were then characterized with SEM and XRF. The corrosion behavior of the coated specimens was evaluated by immersion test in 0.9 wt% NaCl solution at 37°C for 14 days. The results indicated that the coating material improved the corrosion resistance of the AZ31 alloy.

  17. Surface roughness optimization in machining of AZ31 magnesium alloy using ABC algorithm

    Abhijith

    2018-01-01

    Full Text Available Magnesium alloys serve as excellent substitutes for materials traditionally used for engine block heads in automobiles and gear housings in aircraft industries. AZ31 is a magnesium alloy finds its applications in orthopedic implants and cardiovascular stents. Surface roughness is an important parameter in the present manufacturing sector. In this work optimization techniques namely firefly algorithm (FA, particle swarm optimization (PSO and artificial bee colony algorithm (ABC which are based on swarm intelligence techniques, have been implemented to optimize the machining parameters namely cutting speed, feed rate and depth of cut in order to achieve minimum surface roughness. The parameter Ra has been considered for evaluating the surface roughness. Comparing the performance of ABC algorithm with FA and PSO algorithm, which is a widely used optimization algorithm in machining studies, the results conclude that ABC produces better optimization when compared to FA and PSO for optimizing surface roughness of AZ 31.

  18. Surface characterization and cytocompatibility evaluation of silanized magnesium alloy AZ91 for biomedical applications

    Agnieszka Witecka, Akiko Yamamoto, Henryk Dybiec and Wojciech Swieszkowski

    2012-01-01

    Full Text Available Mg alloys with high Al contents have superior corrosion resistance in aqueous environments, but poor cytocompatibility compared to that of pure Mg. We have silanized the cast AZ91 alloy to improve its cytocompatibility using five different silanes: ethyltriethoxysilane (S1, 3-aminopropyltriethoxysilane (S2, 3-isocyanatopyltriethoxysilane (S3, phenyltriethoxysilane (S4 and octadecyltriethoxysilane (S5. The surface hydrophilicity/hydrophobicity was evaluated by water contact angle measurements. X-ray photoelectron analysis was performed to investigate the changes in surface states and chemical composition. All silane reagents increased adsorption of the albumin to the modified surface. In vitro cytocompatibility evaluation revealed that silanization improved cell growth on AZ91 modified by silane S1. Measurement of the concentration of Mg2+ ions released during the cell culture indicated that silanization does not affect substrate degradation.

  19. Evolution of twinning in extruded AZ31 alloy with bimodal grain structure

    Garcés, G., E-mail: ggarces@cenim.csic.es [Department of Physical Metallurgy, National Centre for Metallurgical Research CENIM-CSIC, Av. De Gregorio del Amo 8, 28040 Madrid (Spain); Oñorbe, E. [CIEMAT, Division of Structural Materials, Avenida Complutense, 40, 28040 Madrid (Spain); Gan, W. [German Engineering Materials Science Centre at MLZ, Helmholtz-Zentrum Geesthacht, Lichtebergstr. 1, D-85747 Garching (Germany); Máthis, K. [Department of Physics of Materials, Faculty of Mathematics and Physics, Charles University, KeKarlovu 5, 121 16 Praha 2 (Czech Republic); Tolnai, D. [Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Str. 1, 21502 Geesthacht (Germany); Horváth, K. [Department of Physics of Materials, Faculty of Mathematics and Physics, Charles University, KeKarlovu 5, 121 16 Praha 2 (Czech Republic); Pérez, P.; Adeva, P. [Department of Physical Metallurgy, National Centre for Metallurgical Research CENIM-CSIC, Av. De Gregorio del Amo 8, 28040 Madrid (Spain)

    2017-04-15

    Twinning in extruded AZ31 alloy with a bimodal grain structure is studied under compression along the extrusion direction. This study has combined in-situ measurements during the compression tests by Synchrotron Radiation Diffraction and Acoustic Emission techniques and the evaluation of the microstructure and texture in post-mortem compression samples deformed at different strains. The microstructure of the alloy is characterized by the coexistence of large areas of fine dynamic recrystallized grains and coarse non-recrystallized grains elongated along extrusion direction. Twinning occurs initially in large elongated grains before the macroscopic yield stress which is controlled by the twinning in equiaxed dynamically recrystallized grains. - Highlights: • The AZ31 extruded at low temperature exhibits a bimodal grains structure. • Twinning takes place before macroscopic yielding in coarse non-DRXed grains. • DRXed grains controls the beginning of plasticity in magnesium alloys with bimodal grain structure.

  20. Reactive Sequencing for Autonomous Navigation Evolving from Phoenix Entry, Descent, and Landing

    Grasso, Christopher A.; Riedel, Joseph E.; Vaughan, Andrew T.

    2010-01-01

    Virtual Machine Language (VML) is an award-winning advanced procedural sequencing language in use on NASA deep-space missions since 1997, and was used for the successful entry, descent, and landing (EDL) of the Phoenix spacecraft onto the surface of Mars. Phoenix EDL utilized a state-oriented operations architecture which executed within the constraints of the existing VML 2.0 flight capability, compatible with the linear "land or die" nature of the mission. The intricacies of Phoenix EDL included the planned discarding of portions of the vehicle, the complex communications management for relay through on-orbit assets, the presence of temporally indeterminate physical events, and the need to rapidly catch up four days of sequencing should a reboot of the spacecraft flight computer occur shortly before atmospheric entry. These formidable operational challenges led to new techniques for packaging and coordinating reusable sequences called blocks using one-way synchronization via VML sequencing global variable events. The coordinated blocks acted as an ensemble to land the spacecraft, while individually managing various elements in as simple a fashion as possible. This paper outlines prototype VML 2.1 flight capabilities that have evolved from the one-way synchronization techniques in order to implement even more ambitious autonomous mission capabilities. Target missions for these new capabilities include autonomous touch-and-go sampling of cometary and asteroidal bodies, lunar landing of robotic missions, and ultimately landing of crewed lunar vehicles. Close proximity guidance, navigation, and control operations, on-orbit rendezvous, and descent and landing events featured in these missions require elaborate abort capability, manifesting highly non-linear scenarios that are so complex as to overtax traditional sequencing, or even the sort of one-way coordinated sequencing used during EDL. Foreseeing advanced command and control needs for small body and lunar landing

  1. Effect of Rare Earth on Corrosion Products and Impedance Behavior of AZ91 Magnesium Alloy Under Dry-wet Cycles

    ZHAO Xi

    2017-04-01

    Full Text Available The effect of mischmetal of lanthanum and cerium on the composition and structure of the corrosion products on the surface of AZ91 Mg alloy in deicing salt solution under dry-wet cycles was investigated by scanning electron microscopy (SEM, X-ray diffraction (XRD and energy dispersive spectrometer (EDS. The results show that the corrosion products of AZ91 Mg alloy without mischmetal addition (La,Ce are mainly composed of Mg(OH2, MgO, CaCO3 and Mg6Al2CO3(OH16·4H2O; and (La,CeAlO3 can be found in the products of AZ91 with mischmetal addition, meanwhile dense layer occurs in the corrosion products. Electrochemical impedance spectroscopy (EIS measurements show that the charge transfer resistance of AZ91 alloy with mischmetal addition tested in the same dry-wet cycles is much higher than that of AZ91 alloy, the addition of mischmetal helps to reduce the dispersing effect of impedance spectroscopy, indicating that the corrosion resistance of AZ91 Mg alloy and the stability of corrosion product films can be improved by mischmetal of La and Ce.

  2. TIP48/Reptin and H2A.Z requirement for initiating chromatin remodeling in estrogen-activated transcription.

    Mathieu Dalvai

    2013-04-01

    Full Text Available Histone variants, including histone H2A.Z, are incorporated into specific genomic sites and participate in transcription regulation. The role of H2A.Z at these sites remains poorly characterized. Our study investigates changes in the chromatin environment at the Cyclin D1 gene (CCND1 during transcriptional initiation in response to estradiol in estrogen receptor positive mammary tumour cells. We show that H2A.Z is present at the transcription start-site and downstream enhancer sequences of CCND1 when the gene is poorly transcribed. Stimulation of CCND1 expression required release of H2A.Z concomitantly from both these DNA elements. The AAA+ family members TIP48/reptin and the histone variant H2A.Z are required to remodel the chromatin environment at CCND1 as a prerequisite for binding of the estrogen receptor (ERα in the presence of hormone. TIP48 promotes acetylation and exchange of H2A.Z, which triggers a dissociation of the CCND1 3' enhancer from the promoter, thereby releasing a repressive intragenic loop. This release then enables the estrogen receptor to bind to the CCND1 promoter. Our findings provide new insight into the priming of chromatin required for transcription factor access to their target sequence. Dynamic release of gene loops could be a rapid means to remodel chromatin and to stimulate transcription in response to hormones.

  3. Comparison of simulants to actual neutralized current acid waste: process and product testing of three NCAW core samples from Tanks 101-AZ and 102-AZ

    Morrey, E.V.; Tingey, J.M.; Elliott, M.L.

    1996-10-01

    A vitrification plant is planned to process the high-level waste (HLW) solids from Hanford Site tanks into canistered glass logs for disposal in a national repository. Programs were established within the Pacific Northwest Laboratory Vitrification Technology Development (PVTD) Project to test and model simulated waste to support design, feed processability, operations, permitting, safety, and waste-form qualification. Parallel testing with actual radioactive waste was performed on a laboratory-scale to confirm the validity of using simulants and glass property models developed from simulants. Laboratory-scale testing has been completed on three radioactive core samples from tanks 101-AZ and 102-AZ containing neutralized current acid waste (NCAW), which is one of the first waste types to be processed in the high-level waste vitrification plant under a privatization scenario. Properties of the radioactive waste measured during process and product testing were compared to simulant properties and model predictions to confirm the validity of simulant and glass property ,models work. This report includes results from the three NCAW core samples, comparable results from slurry and glass simulants, and comparisons to glass property model predictions.

  4. Comparison of simulants to actual neutralized current acid waste: Process and product testing of three NCAW core samples from Tanks 101-AZ and 102-AZ

    Morrey, E.V.; Tingey, J.M.

    1996-04-01

    A vitrification plant is planned to process the high-level waste (HLW) solids from Hanford Site tanks into canistered glass logs for disposal in a national repository. Programs have been established within the Pacific Northwest Laboratory Vitrification Technology Development (PVTD) Project to test and model simulated waste to support design, feed processability, operations, permitting, safety, and waste-form qualification. Parallel testing with actual radioactive waste is being performed on a laboratory-scale to confirm the validity of using simulants and glass property models developed from simulants. Laboratory-scale testing has been completed on three radioactive core samples from tanks 101-AZ and 102-AZ containing neutralized current acid waste (NCAW), which is one of the first waste types to be processed in the high-level waste vitrification plant under a privatization scenario. Properties of the radioactive waste measured during process and product testing were compared to simulant properties and model predictions to confirm the validity of simulant and glass property models work. This report includes results from the three NCAW core samples, comparable results from slurry and glass simulants, and comparisons to glass property model predictions.

  5. Mechanical properties of AZ31 alloy processed by a green metallurgy route; Propiedades mecanicas de la aleacion AZ31 procesada por una ruta eco-sostenible

    D' Enrico, F.; Garces, G.; Hofer, M.; Kim, S. K.; Perez, P.; Cabeza, S.; Adeva, P.

    2013-07-01

    Recently it has been proved that molding of defect-free components of various commercial alloys of magnesium can be carried out successfully when small amounts of CaO are added to the melt, making unnecessary the use of SF{sub 6} coverage. In the case of AZ alloys, this process also remarkably improves their mechanical properties not only by the greater cleaning of alloys but also by the formation of CaAl{sub 2} phase. This work, part of the Green project Metallurgy (http://www.green-metallurgy.eu) funded by the European Union (LIFE+2009), studies the influence of different CaO additions on the microstructure and mechanical properties of AZ31 Eco-Mg alloy. The alloy was processed by a conventional route involving extrusion of as-cast rods as well as by a powder metallurgy route (PM) using chips as starting material. The objective was to analyze the viability of recycling machining chips to manufacture components for the automobile industry and transportation in general, because of its low cost and environmental impact. It has been demonstrated that alloys processed from chips exhibit the highest tensile stress values, close to 320 MPa. (Author)

  6. Comparison of simulants to actual neutralized current acid waste: process and product testing of three NCAW core samples from Tanks 101-AZ and 102-AZ

    Morrey, E.V.; Tingey, J.M.; Elliott, M.L.

    1996-10-01

    A vitrification plant is planned to process the high-level waste (HLW) solids from Hanford Site tanks into canistered glass logs for disposal in a national repository. Programs were established within the Pacific Northwest Laboratory Vitrification Technology Development (PVTD) Project to test and model simulated waste to support design, feed processability, operations, permitting, safety, and waste-form qualification. Parallel testing with actual radioactive waste was performed on a laboratory-scale to confirm the validity of using simulants and glass property models developed from simulants. Laboratory-scale testing has been completed on three radioactive core samples from tanks 101-AZ and 102-AZ containing neutralized current acid waste (NCAW), which is one of the first waste types to be processed in the high-level waste vitrification plant under a privatization scenario. Properties of the radioactive waste measured during process and product testing were compared to simulant properties and model predictions to confirm the validity of simulant and glass property ,models work. This report includes results from the three NCAW core samples, comparable results from slurry and glass simulants, and comparisons to glass property model predictions

  7. Comparison of simulants to actual neutralized current acid waste: Process and product testing of three NCAW core samples from Tanks 101-AZ and 102-AZ

    Morrey, E.V.; Tingey, J.M.

    1996-04-01

    A vitrification plant is planned to process the high-level waste (HLW) solids from Hanford Site tanks into canistered glass logs for disposal in a national repository. Programs have been established within the Pacific Northwest Laboratory Vitrification Technology Development (PVTD) Project to test and model simulated waste to support design, feed processability, operations, permitting, safety, and waste-form qualification. Parallel testing with actual radioactive waste is being performed on a laboratory-scale to confirm the validity of using simulants and glass property models developed from simulants. Laboratory-scale testing has been completed on three radioactive core samples from tanks 101-AZ and 102-AZ containing neutralized current acid waste (NCAW), which is one of the first waste types to be processed in the high-level waste vitrification plant under a privatization scenario. Properties of the radioactive waste measured during process and product testing were compared to simulant properties and model predictions to confirm the validity of simulant and glass property models work. This report includes results from the three NCAW core samples, comparable results from slurry and glass simulants, and comparisons to glass property model predictions

  8. Influence of Heat Treatment on the Corrosion Behavior of Purified Magnesium and AZ31 Alloy

    Khalifeh, Sohrab; Burleigh, T. David

    2017-01-01

    Magnesium and its alloys are ideal for biodegradable implants due to their biocompatibility and their low-stress shielding. However, they can corrode too rapidly in the biological environment. The objective of this research was to develop heat treatments to slow the corrosion of high purified magnesium and AZ31 alloy in simulated body fluid at 37{\\deg}C. Heat treatments were performed at different temperatures and times. Hydrogen evolution, weight loss, PDP, and EIS methods were used to measu...

  9. Mechanical behaviour of biodegradable AZ31 magnesium alloy after long term in vitro degradation.

    Adekanmbi, Isaiah; Mosher, Christopher Z; Lu, Helen H; Riehle, Mathis; Kubba, Haytham; Tanner, K Elizabeth

    2017-08-01

    Biodegradable magnesium alloys including AZ31 are exciting candidates for temporary implants as they eliminate the requirement for surgical removal, yet have higher mechanical properties than degradable polymers. However, the very long term mechanical properties and degradation of these alloys have not been fully characterized. The tensile, bending and corrosion behaviour of biodegradable AZ31 Mg alloy specimens have been investigated for up to 9months in vitro in phosphate buffered saline (PBS). Small AZ31 Mg specimens showed a significant drop in bend yield strength and modulus after 3months in vitro degradation and an average mass loss of 6.1%. Larger dumbbell specimens showed significant drops in tensile strength from 251.96±3.53MPa to 73.5±20.2MPa and to 6.43±0.9MPa and in modulus from 47.8±5.6GPa to 25.01±3.4GPa and 2.36±0.89GPa after 3 and 9months respectively. These reductions were accompanied by an average mass loss of 18.3% in 9months. Degradation rate for the small and large specimens followed similar profiles with immersion time, with peak degradation rates of 0.1747gm -2 h - 1 and 0.0881gm -2 h - 1 , and average rates of 0.1038gm -2 h - 1 and 0.0397gm -2 h - 1 respectively. SEM fractography and polished specimen cross-sections revealed corrosion pits, cracks and corrosion induced defects. These data indicate the potential of AZ31 Mg for use in implants that require medium term degradation with load bearing mechanical properties. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Influence of Zeolite Coating on the Corrosion Resistance of AZ91D Magnesium Alloy

    Banerjee, P. Chakraborty; Woo, Ren Ping; Grayson, Sam Matthew; Majumder, Amrita; Raman, R. K. Singh

    2014-01-01

    The protective performance of zeolite coating on AZ91D magnesium alloy was evaluated using potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS) in 0.1 M sodium chloride solution (NaCl). Electrical equivalent circuit (EEC) was developed based upon hypothetical corrosion mechanisms and simulated to correspond to the experimental data. The morphology and the chemical nature of the coating were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD...

  11. Metallurgical bond between magnesium AZ91 alloy and aluminium plasma sprayed coatings

    Kubatík, Tomáš František; Pala, Zdeněk; Neufuss, Karel; Vilémová, Monika; Mušálek, Radek; Stoulil, J.; Slepička, P.; Chráska, Tomáš

    2015-01-01

    Roč. 282, November (2015), s. 163-170 ISSN 0257-8972 R&D Projects: GA ČR(CZ) GP14-31538P Institutional support: RVO:61389021 Keywords : Plasma spraying * AZ91 magnesium alloy * Aluminium * Metallurgical bond * X-ray diffraction Subject RIV: JK - Corrosion ; Surface Treatment of Materials Impact factor: 2.139, year: 2015 http://www.sciencedirect.com/science/article/pii/S0257897215303297

  12. Effect of ECAP on microstructure and mechanical properties of cast AZ91 magnesium alloy

    Chung, C W; Gao, W; Ding, R G; Chiu, Y L

    2010-01-01

    An as-cast AZ91 magnesium alloy was processed by Equal Channel Angular Pressing (ECAP) at 320 0 C. The microstructure and mechanical properties were studied. It has been found that ECAP refines both the grains and precipitates, thus modifies the strength and ductility of the processed alloy. After the first pass of ECAP, the yield stress improves significantly from 71 MPa to 140 MPa.

  13. Hydroxyapatite coating on AZ91 magnesium alloy via sol-gel method

    Albayrak, Sevda; Çinici, Hanifi; Çalın, Recep; Cömert, Canser

    2018-01-01

    Producinga material lighter than available biomaterials, having corrosion-resistance tobiological attacks and histocompatible similar to the bone structure in orderto use in biomedical applications is the purpose of this study. Lightness isextremely important in biomedical applications because stainless steel and manyof the similar heavy metallic alloys can lead to infection by causing harm totissues around the implant when it is used in the body. Although the lightnessof AZ91 Mg alloy is an ...

  14. Ecosystem services and urban heat riskscape moderation: water, green spaces, and social inequality in Phoenix, USA.

    Jenerette, G Darrel; Harlan, Sharon L; Stefanov, William L; Martin, Chris A

    2011-10-01

    Urban ecosystems are subjected to high temperatures--extreme heat events, chronically hot weather, or both-through interactions between local and global climate processes. Urban vegetation may provide a cooling ecosystem service, although many knowledge gaps exist in the biophysical and social dynamics of using this service to reduce climate extremes. To better understand patterns of urban vegetated cooling, the potential water requirements to supply these services, and differential access to these services between residential neighborhoods, we evaluated three decades (1970-2000) of land surface characteristics and residential segregation by income in the Phoenix, Arizona, USA metropolitan region. We developed an ecosystem service trade-offs approach to assess the urban heat riskscape, defined as the spatial variation in risk exposure and potential human vulnerability to extreme heat. In this region, vegetation provided nearly a 25 degrees C surface cooling compared to bare soil on low-humidity summer days; the magnitude of this service was strongly coupled to air temperature and vapor pressure deficits. To estimate the water loss associated with land-surface cooling, we applied a surface energy balance model. Our initial estimates suggest 2.7 mm/d of water may be used in supplying cooling ecosystem services in the Phoenix region on a summer day. The availability and corresponding resource use requirements of these ecosystem services had a strongly positive relationship with neighborhood income in the year 2000. However, economic stratification in access to services is a recent development: no vegetation-income relationship was observed in 1970, and a clear trend of increasing correlation was evident through 2000. To alleviate neighborhood inequality in risks from extreme heat through increased vegetation and evaporative cooling, large increases in regional water use would be required. Together, these results suggest the need for a systems evaluation of the

  15. Corrosion characterization of micro-arc oxidization composite electrophoretic coating on AZ31B magnesium alloy

    Wang, Congjie [School of Materials Science and Engineering, Xi’an University of Technology, Xi’an 710048 (China); Jiang, Bailing [School of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816 (China); Liu, Ming [General Motors China Science Lab, Shanghai 201206 (China); Ge, Yanfeng [School of Materials Science and Engineering, Xi’an University of Technology, Xi’an 710048 (China)

    2015-02-05

    Highlights: • A new protective composite coatings were prepared on AZ31B Mg alloy. • The E-coat locked into MAO coat by discharge channels forming a smoother and compact surface without defects. • Comparing with MAO coat, the MAOE composite coat could provide an excellent barrier for bare Mg against corrosion attack. - Abstract: A two layer composite coating system was applied on the surface of AZ31B magnesium alloy by Micro-arc Oxidation (MAO) plus electrophoretic coat (E-coat) technique. The Mg sample coated with MAO plus E-coat (MAOE) was compared with bare Mg and Mg sample coated by MAO only. The surface microstructure and cross section of bare and coated Mg before and after corrosion were examined by Scanning Electron Microscopy (SEM). The corrosion performance of bare and coated Mg was evaluated using electrochemical measurement and hydrogen evolution test. The results indicated that the corrosion resistance of AZ31B Mg alloy was significantly improved by MAOE composite coating. The corrosion mechanism of bare and coated Mg is discussed.

  16. Formation and mechanism of nanocrystalline AZ91 powders during HDDR processing

    Liu, Yafen; Fan, Jianfeng, E-mail: fanjianfeng@tyut.edu.cn; Zhang, Hua; Zhang, Qiang; Gao, Jing; Dong, Hongbiao, E-mail: hd38@leicester.ac.uk; Xu, Bingshe

    2017-03-15

    Grain sizes of AZ91 alloy powders were markedly refined to about 15 nm from 100 to 160 μm by an optimized hydrogenation-disproportionation-desorption-recombination (HDDR) process. The effect of temperature, hydrogen pressure and processing time on phase and microstructure evolution of AZ91 alloy powders during HDDR process was investigated systematically by X-ray diffraction, optical microscopy, scanning electron microscopy and transmission electron microscopy, respectively. The optimal HDDR process for preparing nanocrystalline Mg alloy powders is hydriding at temperature of 350 °C under 4 MPa hydrogen pressure for 12 h and dehydriding at 350 °C for 3 h in vacuum. A modified unreacted core model was introduced to describe the mechanism of grain refinement of during HDDR process. - Highlights: • Grain size of the AZ91 alloy powders was significantly refined from 100 μm to 15 nm. • The optimal HDDR technology for nano Mg alloy powders is obtained. • A modified unreacted core model of grain refinement mechanism was proposed.

  17. Wire Arc Additive Manufacturing of AZ31 Magnesium Alloy: Grain Refinement by Adjusting Pulse Frequency

    Jing Guo

    2016-10-01

    Full Text Available Wire arc additive manufacturing (WAAM offers a potential approach to fabricate large-scale magnesium alloy components with low cost and high efficiency, although this topic is yet to be reported in literature. In this study, WAAM is preliminarily applied to fabricate AZ31 magnesium. Fully dense AZ31 magnesium alloy components are successfully obtained. Meanwhile, to refine grains and obtain good mechanical properties, the effects of pulse frequency (1, 2, 5, 10, 100, and 500 Hz on the macrostructure, microstructure and tensile properties are investigated. The results indicate that pulse frequency can result in the change of weld pool oscillations and cooling rate. This further leads to the change of the grain size, grain shape, as well as the tensile properties. Meanwhile, due to the resonance of the weld pool at 5 Hz and 10 Hz, the samples have poor geometry accuracy but contain finer equiaxed grains (21 μm and exhibit higher ultimate tensile strength (260 MPa and yield strength (102 MPa, which are similar to those of the forged AZ31 alloy. Moreover, the elongation of all samples is above 23%.

  18. Study on fluidity of squeeze cast AZ91D magnesium alloy with different wall thicknesses

    Chen Yun

    2014-03-01

    Full Text Available Rectangular cross-section specimens with different section thicknesses were prepared to study the influences of pouring temperature, mould temperature and squeeze velocity on the fluidity of squeeze cast AZ91D magnesium alloy by means of orthogonal test design method. The results show that pouring temperature, mould temperature and squeeze velocity can significantly affect the fluidity of magnesium alloy specimens with wall thickness no more than 4 mm, and the pouring temperature is the most influential factor on the fluidity of specimens with wall thickness of 1, 2 and 3 mm, while mould temperature is the one for specimens with wall thickness of 4 mm. Increasing pouring temperature between 700 °C and 750 °C is beneficial to the fluidity of AZ91D magnesium alloy, and increasing mould temperature significantly enhances the filling ability of thick (3 and 4 mm section castings. The fluidity of squeeze cast magnesium alloy increases with the increase of wall thickness. It is not recommended to produce magnesium alloy casting with wall thickness of smaller than 3 mm by squeeze cast process due to the poor fluidity. The software DPS was used to generate the regression model, and linear regression equations of the fluidity of squeeze cast AZ91D with different wall thicknesses are obtained using the test results.

  19. The effect of PVD coatings on the corrosion behaviour of AZ91 magnesium alloy

    Altun, Hikmet; Sen, Sadri

    2006-01-01

    In this study, multilayered AlN (AlN + AlN + AlN) and AlN + TiN were coated on AZ91 magnesium alloy using physical vapour deposition (PVD) technique of DC magnetron sputtering, and the influence of the coatings on the corrosion behaviour of the AZ91 alloy was examined. A PVD system for coating processes, a potentiostat for electrochemical corrosion tests, X-ray difractometer for compositional analysis of the coatings, and scanning electron microscopy for surface examinations were used. It was determined that PVD coatings deposited on AZ91 magnesium alloy increased the corrosion resistance of the alloy, and AlN + AlN + AlN coating increased the corrosion resistance much more than AlN + TiN coating. However, it was observed that, in the coating layers, small structural defects e.g., pores, pinholes, cracks that could arise from the coating process or substrate and get the ability of protection from corrosion worsened were present

  20. Cerium Addition Improved the Dry Sliding Wear Resistance of Surface Welding AZ91 Alloy

    Qingqiang Chen

    2018-02-01

    Full Text Available In this study, the effects of cerium (Ce addition on the friction and wear properties of surface welding AZ91 magnesium alloys were evaluated by pin-on-disk dry sliding friction and wear tests at normal temperature. The results show that both the friction coefficient and wear rate of surfacing magnesium alloys decreased with the decrease in load and increase in sliding speed. The surfacing AZ91 alloy with 1.5% Ce had the lowest friction coefficient and wear rate. The alloy without Ce had the worst wear resistance, mainly because it contained a lot of irregularly shaped and coarse β-Mg17Al12 phases. During friction, the β phase readily caused stress concentration and thus formed cracks at the interface between β phase and α-Mg matrix. The addition of Ce reduced the size and amount of Mg17Al12, while generating Al4Ce phase with a higher thermal stability. The Al-Ce phase could hinder the grain-boundary sliding and migration and reduced the degree of plastic deformation of subsurface metal. Scanning electron microscopy observation showed that the surfacing AZ91 alloy with 1.5% Ce had a total of four types of wear mechanism: abrasion, oxidation, and severe plastic deformation were the primary mechanisms; delamination was the secondary mechanism.

  1. Electrodeposition of Al-Mn alloy on AZ31B magnesium alloy in molten salts

    Zhang Jifu; Yan Chuanwei; Wang Fuhui

    2009-01-01

    The Al-Mn alloy coatings were electrodeposited on AZ31B Mg alloy in AlCl 3 -NaCl-KCl-MnCl 2 molten salts at 170 deg. C aiming to improve the corrosion resistance. However, in order to prevent AZ31B Mg alloy from corrosion during electrodeposition in molten salts and to ensure excellent adhesion of coatings to the substrate, AZ31B Mg alloy should be pre-plated with a thin zinc layer as intermediate layer. Then the microstructure, composition and phase constituents of the coatings were investigated by scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDX), and X-ray diffraction (XRD). It was indicated that, by adjusting the MnCl 2 content in the molten salts from 0.5 wt% to 2 wt%, the Mn content in the alloy coating was increased and the phase constituents were changed from f.c.c Al-Mn solid solution to amorphous phase. The corrosion resistance of the coatings was evaluated by potentiodynamic polarization measurements in 3.5% NaCl solution. It was confirmed that the Al-Mn alloy coatings exhibited good corrosion resistance with a chear passive region and significantly reduced corrosion current density at anodic potentiodynamic polarization. The corrosion resistance of the alloy coatings was also related with the microstructure and Mn content of the coatings.

  2. Precipitation behavior and effect of new precipitated β phase in AZ80 magnesium alloy

    TANG Wei; HAN En-hou; XU Yong-bo; LIU Lu

    2006-01-01

    Granular precipitate that was a new kind of β-Mg17Al12 phase found in aged AZ80 wrought Mg alloy at all aging temperature was studied. The structure and precipitation behavior of this granular β-Mg17Al12 precipitate were studied by environmental scanning electron microscopy (ESEM) and transmission electron microscopy (TEM). The effect of the granular precipitate on mechanical properties of AZ80 alloy was also studied. The new precipitate that was granular and nucleated both on grain boundaries (GBs) and twin boundaries, has the same crystal structure and lattice parameter as those of the continuous or discontinuous precipitated β-Mg17Al12. And the nucleation and growth of the granular precipitate are faster than those of the other two precipitates at higher temperatures (above 583 K), but are suppressed at lower temperatures (below 423 K). At lower temperatures, the discontinuous β-Mg17Al12 precipitates firstly and the granular β-Mg17Al12 precipitates after aged more than 40 h. The crack is easily nucleated on the phase boundaries of granular phase and matrix because of the weak binding force. As a result, the strength and ductility of AZ80 Mg alloy are decreased by the granular β-Mg17Al12 precipitate.

  3. Influence of heat treatment on the machinability and corrosion behavior of AZ91 Mg alloy

    Swetha Chowdary V

    2018-03-01

    Full Text Available In the present study, AZ91 Mg alloy was heat treated at 410 °C for 6, 12 and 24 h to investigate the influence of heat treatment on machinability and corrosion behavior. The effect of soaking time on the amount and distribution of Mg17Al12 (β – phase was analyzed under the optical microscope. Microhardness measurements demonstrated the increased hardness with increased heat treatment soaking time, which can be attributed to the solid solution strengthening. The influence of super saturated α-grains on reducing the cutting force (Fz with respect to increased cutting speed was observed as prominent. The corrosion behavior of the heat treated specimens was studied by conducting electrochemical tests. Surprisingly, corrosion rate of heat treated samples was observed as increased compared with the base material. From the results, it is evident that the machinability of AZ91 Mg alloy can be improved by producing super saturated α-grains through heat treatment but at the cost of losing corrosion resistance. Keywords: AZ91 Mg alloy, Solid solution, Turning, Corrosion, Machinability

  4. Corrosion of AZ91D magnesium alloy with a chemical conversion coating and electroless nickel layer

    Huo Hongwei; Li Ying; Wang Fuhui

    2004-01-01

    A chemical conversion treatment and an electroless nickel plating were applied to AZ91D alloy to improve its corrosion resistance. By conversion treatment in alkaline stannate solution, the corrosion resistance of the alloy was improved to some extent as verified by immersion test and potentiodynamic polarization test in 3.5 wt.% NaCl solution at pH 7.0. X-ray diffraction patterns of the stannate treated AZ91D alloy showed the presence of MgSnO 3 · H 2 O, and SEM images indicated a porous structure, which provided advantage for the adsorption during sensitisation treatment prior to electroless nickel plating. A nickel coating with high phosphorus content was successfully deposited on the chemical conversion coating pre-applied to AZ91D alloy. The presence of the conversion coating between the nickel coating and the substrate reduced the potential difference between them and enhanced the corrosion resistance of the alloy. An obvious passivation occurred for the nickel coating during anodic polarization in 3.5 wt.% NaCl solution

  5. Flow behaviour of magnesium alloy AZ31B processed by equal-channel angular pressing

    Arun, M S; Chakkingal, U

    2014-01-01

    Magnesium alloys are characterised by their low density, high specific strength and stiffness. But, the potential application of Mg is limited by its low room-temperature ductility and formability. Formability can be improved by developing an ultrafine grained (UFG) structure. Equal channel angular pressing (ECAP) is a well known process that can be used to develop an ultrafine grained microstructure. The aim of this study was to investigate the flow behaviour of AZ31B magnesium alloy after ECAP. The specimen was subjected to three passes of ECAP with a die angle of 120° using processing route Bc. The processing temperature was 523 K for the first pass and 423 K for the subsequent two passes. The microstructure characterisation was done. Compression tests of ECAPed and annealed specimens were carried out at strain rates of 0.01 – 1s −1 and deformation temperatures of 200 – 300°C using computer servo-controlled Gleeble-3800 system. The value of activation energy Q and the empirical materials constants of A and n were determined. The equations relating flow stress and Zener-Hollomon parameter were proposed. In the case annealed AZ31, the activation energy was determined to be 154 kJ/mol, which was slightly higher than the activation energy of 144 kJ/mol for ECAPed AZ31

  6. Flow behaviour of magnesium alloy AZ31B processed by equal-channel angular pressing

    Arun, M. S.; Chakkingal, U.

    2014-08-01

    Magnesium alloys are characterised by their low density, high specific strength and stiffness. But, the potential application of Mg is limited by its low room-temperature ductility & formability. Formability can be improved by developing an ultrafine grained (UFG) structure. Equal channel angular pressing (ECAP) is a well known process that can be used to develop an ultrafine grained microstructure. The aim of this study was to investigate the flow behaviour of AZ31B magnesium alloy after ECAP. The specimen was subjected to three passes of ECAP with a die angle of 120° using processing route Bc. The processing temperature was 523 K for the first pass and 423 K for the subsequent two passes. The microstructure characterisation was done. Compression tests of ECAPed and annealed specimens were carried out at strain rates of 0.01 - 1s-1 and deformation temperatures of 200 - 300°C using computer servo-controlled Gleeble-3800 system. The value of activation energy Q and the empirical materials constants of A and n were determined. The equations relating flow stress and Zener-Hollomon parameter were proposed. In the case annealed AZ31, the activation energy was determined to be 154 kJ/mol, which was slightly higher than the activation energy of 144 kJ/mol for ECAPed AZ31.

  7. Dry Sliding Wear Charactristics of Aluminum 6061-T6, Magnesium AZ31 and Rock Dust Composite

    Balachandar, R.; Balasundaram, R.; Rajkumar, G.

    2018-02-01

    In recent years, the use of aluminum composite is gaining popularity in a wide range of applications like automobiles, aerospace and constructions (both interior & exterior) panels etc., due to its high strength, low density characteristics. Various reinforcing materials are used with aluminum 6061-T6 in order to have better mechanical properties. The addition of 0.3% of magnesium AZ31 will increase the ultimate tensile strength by 25 %. The reinforcement of rock dust will decrease the density. Hence, in order to have an advantages of magnesium AZ31 and rock dust, in this work, these two constitutes are varied from 1% to 2% on the base material of Al6061-T6 in stir casting. To evaluate the wear characteristics, Pin on disc is used in these composites. The input parameters are speed, time & load. The output response is wear. To minimize the number of experiments, L9 orthogonal array is used. The test results showed that a composite of 97% of Al (6061-T6), 1% Mg (AZ31) & 2 % of rock dust produced less wear. To find the best value of operating parameter for each sample, ANN-GA is used.

  8. Enrique Díaz and Present Phpotographies (From Graphic Notes to Photo-essays

    Rebeca Monroy Nasr

    1998-10-01

    Full Text Available With "Enrique Díaz and Present Phpotographies (From Graphic Notes to Photo-essays ", the author presents part of our photo­graphic history, as well as some aspects of its development as a form of journalism and of art. She rescues the figure of Enrique Díaz Reyna as representative of the union of graphic journalists, due to his technical, formal and conceptual traits, all of them tools with which he opened important paths and innovative graphical and aesthetic proposals. This essay presents some aspects of the graphic journalist's work in Mexico City, from the twenties to the forties. As a guide to the photographer's extensi­ve work, the author reviews some of the proposals he made as his work became more mature: first, the graphic note, later, recrea­ting the photo-reportage, and finally, exploring with photoessays. Thus, attention is centered particularly on Díaz Reyna's visual language, where the signs of a distinctive modernity appro­priate of his time allow us to understand a substantial part of the transition towards a contemporary and  truly national photo-journalism.

  9. Tank 241-AZ-102 Privatization Push Mode Core Sampling and Analysis Plan

    RASMUSSEN, J.H.

    1999-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for samples obtained from tank 241-AZ-102. The purpose of this sampling event is to obtain information about the characteristics of the contents of 241-AZ-102 required to satisfy the Data Quality Objectives For TWRS Privatization Phase I : Confirm Tank TIS An Appropriate Feed Source For High-Level Waste Feed Batch X(HLW DQO) (Nguyen 1999a), Data Quality Objectives For TWRS Privatization Phase 1: Confirm Tank TIS An Appropriate Feed Source For Low-Activity Waste Feed Batch X (LAW DQO) (Nguyen 1999b), Low Activity Waste and High Level Waste Feed Data Quality Objectives (L and H DQO) (Patello et al. 1999) and Characterization Data Needs for Development, Design, and Operation of Retrieval Equipment Developed through the Data Quality Objective Process (Equipment DQO) (Bloom 1996). The Tank Characterization Technical Sampling Basis document (Brown et al. 1998) indicates that these issues, except the Equipment DQO apply to tank 241-AZ-102 for this sampling event. The Equipment DQO is applied for shear strength measurements of the solids segments only. Poppiti (1999) requires additional americium-241 analyses of the sludge segments. Brown et al. (1998) also identify safety screening, regulatory issues and provision of samples to the Privatization Contractor(s) as applicable issues for this tank. However, these issues will not be addressed via this sampling event. Reynolds et al. (1999) concluded that information from previous sampling events was sufficient to satisfy the safety screening requirements for tank 241-AZ-102. Push mode core samples will be obtained from risers 15C and 24A to provide sufficient material for the chemical analyses and tests required to satisfy these data quality objectives. The 222-S Laboratory will extrude core samples, composite the liquids and solids, perform chemical analyses

  10. Lactancia materna, alimentación artificial y el primer contacto con azúcar

    Fabian Calixto Fraiz

    2013-01-01

    Full Text Available Objetivo: Este estudio evaluó los cambios en el patrón de lactancia materna, alimentación artificial y en la introducción de azúcar en la dieta de niños de 0 a 36 meses, a través de dos estudios, con un intervalo de 13 años en la ciudad de Curitiba, Paraná, Brasil. Material y métodos: Poblaciones semejantes de una misma región geográfica fueron evaluadas a través de un cuestionario, en los años de 1993 y 2006, envolviendo, respectivamente, las madres de 180 y 94 niños. Introducción de azúcar en la dieta fue considerada precoz cuando ocurrió antes del 6º mes completo de vida. Los datos fueron analizados estadísticamente a través del test de qui-cuadrado y test exacto de Fisher (α= 0,05. Resultados: Hubo diferencias en la frecuencia del primer contacto con azúcar (p <0,001, que ocurrió en el primer mes de vida en 61,7% de los niños del primer estudio y en sólo 3,2% de los niños del segundo estudio. Hubo diferencias en el patrón de lactancia materna (p = 0,02, siendo la prevalencia de niños amamantados mayor en el segundo estudio. No fueron encontradas diferencias estadísticamente significativas en la prevalencia de uso de biberón, uso de biberón durante la noche y lactancia materna durante la noche, así como en el uso de biberón conteniendo azúcar. Conclusiones: Estos resultados indican que la lactancia materna puede, además de sus varias ventajas, también promover el aplazamiento de la introducción de azúcar en la dieta infantil. Nuevas investigaciones son necesarias para confirmar esta hipótesis.

  11. Strontium-90 fluoride data sheet

    Fullam, H.T.

    1981-06-01

    This report is a compilation of available data and appropriate literature references on the properties of strontium-90 fluoride and nonradioactive strontium fluoride. The objective of the document is to compile in a single source pertinent data to assist potential users in the development, licensing, and use of /sup 90/SrF/sub 2/-fueled radioisotope heat sources for terrestrial power conversion and thermal applications. The report is an update of the Strontium-90 Fluoride Data Sheet (BNWL-2284) originally issued in April 1977.

  12. Vietnamese Hurricane Response Fact Sheets

    Các tờ dữ kiện được cung cấp nơi đây mô tả vai trò của EPA trong việc đáp ứng với bão và cách các chương trình cụ thể cung cấp sự hỗ trợ. The Vietnamese fact sheets provided here describe EPA's role in a hurricane response.

  13. Genetic Diversity of Iraqi Date Palm (Phoenix ‎dactylifera L. by using RAPD Technique

    Muhanned Abdul Hasan Kareem

    2018-01-01

    Full Text Available In this study provided all molecular markers of Random amplified polymorphic (RAPD successfully with the sixty five Iraqi date palm (Phoenix dactylifera L. cultivars, which collected from Hilla city in Iraq, to determine fingerprinting, polymorphic value, and relationships among varieties of date palm cultivars, and also with the same type of cultivars. Data analysis of ten RAPD has been revealed. Number of amplified DNA fragments were (592 bands, polymorphism per all primers were (%64.2, primer efficiency was 0.1, and discriminatory value was (%0.09, which revealed a high percentage similarity about %67 to %100 between cultivars belong to the same variety. There are relationships with twenty four genotypes, divided in to two clusters, clusterΙ ranged distance from 0.74 to 1.30 represented(Maddany, Ashrasi, Greatli, Smeasmi and sukkary and clusterII ranged distance from 0.25 to 0.60 which divided into three sub group, there are sub group I represented (Sultana, Khestawi, Breem, Sabb Drrah, Hamrawi, Brban, and Khadrawi, sub groupiesII represented (Zahdi, Tebarzal, Maktom, brahi, Chipchab and Fom Alrman, sub groupies III represented (Usta Umran, Nersi, Najdi, Guntar, Shwethi and Ghanami Ahmer.

  14. Genetic Diversity of Iraqi Date Palm (Phoenix ‎dactylifera L. by using RAPD Technique

    Muhanned Abdul Hasan

    2017-12-01

    Full Text Available In this study provided all molecular markers of Random amplified polymorphic (RAPD successfully with the sixty five Iraqi date palm (Phoenix dactylifera L. cultivars, which collected from Hilla city in Iraq, to determine fingerprinting, polymorphic value, and relationships among varieties of date palm cultivars, and also with the same type of cultivars. Data analysis of ten RAPD has been revealed. Number of amplified DNA fragments were (592 bands, polymorphism per all primers were (%64.2, primer efficiency was 0.1, and discriminatory value was (%0.09, which revealed a high percentage similarity about %67 to %100 between cultivars belong to the same variety. There are relationships with twenty four genotypes, divided in to two clusters, clusterΙ ranged distance from 0.74 to 1.30 represented(Maddany, Ashrasi, Greatli, Smeasmi and sukkary and clusterII ranged distance from 0.25 to 0.60 which divided into three sub group, there are sub group I represented (Sultana, Khestawi, Breem, Sabb Drrah, Hamrawi, Brban, and Khadrawi, sub groupiesII represented (Zahdi, Tebarzal, Maktom, brahi, Chipchab and Fom Alrman, sub groupies III represented (Usta Umran, Nersi, Najdi, Guntar, Shwethi and Ghanami Ahmer.  

  15. Biosorption of methylene blue from aqueous solution by fallen phoenix tree's leaves

    Han Runping; Zou Weihua; Yu Weihong; Cheng Shujian; Wang Yuanfeng; Shi Jie

    2007-01-01

    A new adsorbent, the fallen phoenix tree's leaf, has been investigated in order to remove methylene blue (MB) from aqueous solutions. Variables of the system, including contact time, leaf dose, solution pH, salt concentration and initial MB concentration, were adopted to study their effects on MB biosorption. The results showed that as the dose of leaf increased, the percentage of MB sorption increased accordingly. There was no significant difference about the quantity of MB adsorbed onto leaf as the pH was within the range 4.5-10.0. The salt concentration has negative effect on MB removal. The equilibrium data were analyzed using the Langmuir and the Freundlich isotherms. The results of non-linear regressive analysis are that the Langmuir isotherm is better fit than the Freundlich isotherm at different temperature according to the values of determined coefficients (R 2 ) and χ 2 -statistic (SS). The Langmuir monolayer saturation capacities of MB adsorbed onto leaf are 80.9, 83.8, 89.7 mg g -1 at 295, 309 and 323 K, respectively. Using the equilibrium concentration contents obtained at different temperatures, various thermodynamic parameters, such as ΔG o , ΔH o and ΔS o , have been calculated. The thermodynamics parameters of MB/leaf system indicate spontaneous and endothermic process. It was concluded that an increase in temperature be advantage to adsorb MB onto leaf

  16. VA office of inspector general releases scathing report of Phoenix VA

    Robbins RA

    2014-08-01

    Full Text Available No abstract available. Article truncated at 150 words. The long-awaited Office of Inspector General’s (OIG report on the Phoenix VA Health Care System (PVAHCS was released on August 27, 2014 (1. The report was scathing in its evaluation of VA practices and leadership. Five questions were investigated: 1.Were there clinically significant delays in care? 2. Did PVAHCS omit the names of veterans waiting for care from its Electronic Wait List (EWL? 3. Were PVAHCS personnel not following established scheduling procedures? 4. Did the PVAHCS culture emphasize goals at the expense of patient care? 5. Are scheduling deficiencies systemic throughout the VA? In each case, the OIG found that the allegations were true. Despite initial denials, the OIG report showed that former PVAHCS director Sharon Helman, associate director Lance Robinson, hospital administration director Brad Curry, chief of staff Darren Deering and other senior executives were aware of delays in care and unofficial wait lists. Perhaps most disturbing is ...

  17. The Phoenix Project: Shifting to a solar hydrogen economy by 2020

    Braun, H.

    2008-01-01

    The most serious energy, economic and environmental problems are related to the use of fossil and nuclear fuels, which are rapidly diminishing and highly polluting, and many distinguished atmospheric chemists, including Dr. James Hanson at NASA, Dr. Steven Chu, the director of Lawrence Livermore Laboratory, and Professor Ralph Cicerone, president of the National Academy of Sciences have documented that climate changes are now occurring much faster than predicted just a few years ago. The methane hydrates in the oceans and the permafrost in vast areas of the Arctic regions of Siberia, Alaska and Canada are now starting to rapidly melt, and given this could release 50 to 100 times more carbon into the atmosphere than is now generated from the burning of fossil fuels, humanity is rapidly approaching an exponential 'tipping point' of no return. Given this sense of urgency, Hanson and others have warned that fossil fuels need to be phased-out by 2020 if irreversible damage to the earth's climate and food production systems is to be avoided. The Phoenix Project plan seeks to do exactly that by mass-producing wind-powered hydrogen production systems and simply modifying all the existing vehicles and power plants to use the hydrogen made from the sun, wind and water

  18. US Geological Survey National Computer Technology Meeting; Proceedings, Phoenix, Arizona, November 14-18, 1988

    Balthrop, Barbara H.; Terry, J.E.

    1991-01-01

    The U.S. Geological Survey National Computer Technology Meetings (NCTM) are sponsored by the Water Resources Division and provide a forum for the presentation of technical papers and the sharing of ideas or experiences related to computer technology. This report serves as a proceedings of the meeting held in November, 1988 at the Crescent Hotel in Phoenix, Arizona. The meeting was attended by more than 200 technical and managerial people representing all Divisions of the U.S. Geological Survey.Scientists in every Division of the U.S. Geological Survey rely heavily upon state-of-the-art computer technology (both hardware and sofnuare). Today the goals of each Division are pursued in an environment where high speed computers, distributed communications, distributed data bases, high technology input/output devices, and very sophisticated simulation tools are used regularly. Therefore, information transfer and the sharing of advances in technology are very important issues that must be addressed regularly.This report contains complete papers and abstracts of papers that were presented at the 1988 NCTM. The report is divided into topical sections that reflect common areas of interest and application. In each section, papers are presented first followed by abstracts. For these proceedings, the publication of a complete paper or only an abstract was at the discretion of the author, although complete papers were encouraged.Some papers presented at the 1988 NCTM are not published in these proceedings.

  19. THE PHOENIX PROJECT: SHIFTING TO A SOLAR HYDROGEN ECONOMY BY 2020

    HARRY BRAUN

    2008-07-01

    Full Text Available The most serious energy, economic and environmental problems are related to the use of fossil and nuclear fuels, which are rapidly diminishing and highly polluting, and many distinguished atmospheric chemists, including Dr. James Hanson at NASA, Dr. Steven Chu, the director of Lawrence Livermore Laboratory, and Professor Ralph Cicerone, president of the National Academy of Sciences have documented that climate changes are now occurring much faster than predicted just a few years ago. The methane hydrates in the oceans and the permafrost in vast areas of the Artic regions of Siberia, Alaska and Canada are now starting to rapidly melt, and given this could release 50 to 100 times more carbon into the atmosphere than is now generated from the burning of fossil fuels, humanity is rapidly approaching an exponential “tipping point” of no return. Given this sense of urgency, Hanson and others have warned that fossil fuels need to be phased-out by 2020 if irreversible damage to the earth’s climate and food production systems is to be avoided. The Phoenix Project plan seeks to do exactly that by mass-producing wind-powered hydrogen production systems and simply modifying all the existing vehicles and power plants to use the hydrogen made from the sun, wind and water.

  20. Profiling microRNA expression during multi-staged date palm (Phoenix dactylifera L.) fruit development

    Xin, Chengqi; Liu, Wanfei; Lin, Qiang; Zhang, Xiaowei; Cui, Peng; Li, Fusen; Zhang, Guangyu; Pan, Linlin; Al-Amer, Ali; Mei, Hailiang; Al-Mssallem, Ibrahim S.; Hu, Songnian; Al-Johi, Hasan Awad; Yu, Jun

    2015-01-01

    MicroRNAs (miRNAs) play crucial roles in multiple stages of plant development and regulate gene expression at posttranscriptional and translational levels. In this study, we first identified 238 conserved miRNAs in date palm (Phoenix dactylifera) based on a high-quality genome assembly and defined 78 fruit-development-associated (FDA) miRNAs, whose expression profiles are variable at different fruit development stages. Using experimental data, we subsequently detected 276 novel P. dactylifera-specific FDA miRNAs and predicted their targets. We also revealed that FDA miRNAs function mainly in regulating genes involved in starch/sucrose metabolisms and other carbon metabolic pathways; among them, 221 FDA miRNAs exhibit negative correlation with their corresponding targets, which suggests their direct regulatory roles on mRNA targets. Our data define a comprehensive set of conserved and novel FDA miRNAs along with their expression profiles, which provide a basis for further experimentation in assigning discrete functions of these miRNAs in P. dactylifera fruit development.

  1. Regional Landscape System Protection in the Urbanising Desert Southwest: Lessons from the Phoenix Metropolitan Region, USA

    Laura Musacchio

    2004-06-01

    Full Text Available Since the late nineteenth century, landscape protection in the deserts of the Southwest, United States of America, like many places worldwide, has been driven by the conservation of landscape icons, such as unusual geological features in wilderness areas. Yet, in the past two decades, leading conservation scholars worldwide have called for a shift in this paradigm to one that emphasises landscape systems, which is based on holistic landscape ecology. The shift in emphas is to landscape systems opens new opportunities to protect desert landscape systems at the regional scale rather than just remnant patches at the local scale. In this paper, the authors present, for public consideration, a typology of the five major desert landscapes that can be used as the bas is for protecting regional landscape systems in the deserts of the Southwest. As a case study, several representative examples of recent regional open space plans from the Phoenix metropolitan area are analysed and compared with the typology in order to understand how successfully the projects have addressed protection of the regional landscape system in the Sonoran Desert.

  2. Crucible of Creativity: Testing Public Outreach Activities at the Phoenix Comicon

    Horodyskyj, L.

    2015-12-01

    The Phoenix Comicon (PCC) is a growing four-day pop culture event that features guests, costuming, exhibits, and discussion panels for popular sci-fi, fantasy, horror, and anime franchises. The 2014 and 2015 shows (which drew 75,000+ unique attendees each) featured a science programming track coordinated and organized by Horodyskyj. The track consisted of discussion panels, mixers, shows, interactive displays, and signature events (over 30 hours of programming each year). Topics ranged from planetary sciences to biotechnology to artificial intelligence and event staff were recruited from all levels of experience in academia, industry, and STEM outreach. The PCC science programming track for both 2014 and 2015 received very positive feedback from the audience, PCC management, and even scientists who participated in the event. Panelists and staff received frequent unsolicited praise about the content and events, and surveys showed requests for more science content in future years. Demand for good science programming, especially the kind that links the audience to local scientists, is high. The unique organizational structure of PCC, which draws heavily on the fan community rather than industry professionals, provides a rich test bed for public outreach activities generated by scientists themselves. In 2014, we tested science-based game shows, such as the bloody Exoplanet Survivor. In 2015, we ran a science interactivity booth and an interactive stage show about forensics based on the BBC series Sherlock. I will detail some of the successes and failures of these various events and what we're planning for 2016.

  3. Relationship between particulate matter and childhood asthma - basis of a future warning system for central Phoenix

    Dimitrova, R.; Lurponglukana, N.; Fernando, H. J. S.; Runger, G. C.; Hyde, P.; Hedquist, B. C.; Anderson, J.; Bannister, W.; Johnson, W.

    2012-03-01

    Statistically significant correlations between increase of asthma attacks in children and elevated concentrations of particulate matter of diameter 10 microns and less (PM10) were determined for metropolitan Phoenix, Arizona. Interpolated concentrations from a five-site network provided spatial distribution of PM10 that was mapped onto census tracts with population health records. The case-crossover statistical method was applied to determine the relationship between PM10 concentration and asthma attacks. For children ages 5-17, a significant relationship was discovered between the two, while children ages 0-4 exhibited virtually no relationship. The risk of adverse health effects was expressed as a function of the change from the 25th to 75th percentiles of mean level PM10 (36 μg m-3). This increase in concentration was associated with a 12.6% (95% CI: 5.8%, 19.4%) increase in the log odds of asthma attacks among children ages 5-17. Neither gender nor other demographic variables were significant. The results are being used to develop an asthma early warning system for the study area.

  4. Analysis of Spatiotemporal Statistical Properties of Rainfall in the Phoenix Metropolitan Area

    Mascaro, G.

    2016-12-01

    The analysis of the rainfall statistical properties at multiple spatiotemporal scales is a necessary preliminary step to support modeling of urban hydrology, including flood prediction and simulation of impacts of land use changes. In this contribution, the rainfall statistical properties are analyzed in the Phoenix Metropolitan area and its surroundings ( 29600 km2) in Arizona using observations from 310 gauges of the Flood Control District of the Maricopa County network. Different techniques are applied to investigate the rainfall properties at temporal scales from 1 min to years and to quantify the associated spatial variability. Results reveal the following. The rainfall regime is characterized by high interannual variability, which is partially explained by teleconnections with El Niño Southern Oscillation, and marked seasonality, with two maxima in the monsoon season from July to September and in winter from November to March. Elevation has a significant control on seasonal rainfall accumulation, strength of thermal convective activity during the monsoon, and peak occurrence of the rainfall diurnal cycle present in summer. The spatial correlation of wintertime rainfall is high even at short aggregation times (cells).

  5. Quantifying Water and Energy Fluxes Over Different Urban Land Covers in Phoenix, Arizona

    Templeton, Nicole P.; Vivoni, Enrique R.; Wang, Zhi-Hua; Schreiner-McGraw, Adam P.

    2018-02-01

    The impact of urbanization on water and energy fluxes varies according to the characteristics of the urban patch type. Nevertheless, urban flux observations are limited, particularly in arid climates, given the wide variety of land cover present in cities. To help address this need, a mobile eddy covariance tower was deployed at three locations in Phoenix, Arizona, to sample the surface energy balance at a parking lot, a xeric landscaping (irrigated trees with gravel) and a mesic landscaping (irrigated turf grass). These deployments were compared to a stationary eddy covariance tower in a suburban neighborhood. A comparison of the observations revealed key differences between the mobile and reference sites tied to the urban land cover within the measurement footprints. For instance, the net radiation varied substantially among the sites in manners consistent with albedo and shallow soil temperature differences. The partitioning of available energy between sensible and latent heat fluxes was modulated strongly by the presence of outdoor water use, with the irrigated turf grass exhibiting the highest evaporative fraction. At this site, we identified a lack of sensitivity of turbulent flux partitioning to precipitation events, which suggests that frequent outdoor water use removes water limitations in an arid climate, thus leading to mesic conditions. Other urban land covers with less irrigation, however, exhibited sensitivity to the occurrence of precipitation, as expected for an arid climate. As a result, quantifying the frequency and magnitude of outdoor water use is critical for understanding evapotranspiration losses in arid urban areas.

  6. Learning to live on a Mars day: fatigue countermeasures during the Phoenix Mars Lander mission.

    Barger, Laura K; Sullivan, Jason P; Vincent, Andrea S; Fiedler, Edna R; McKenna, Laurence M; Flynn-Evans, Erin E; Gilliland, Kirby; Sipes, Walter E; Smith, Peter H; Brainard, George C; Lockley, Steven W

    2012-10-01

    To interact with the robotic Phoenix Mars Lander (PML) spacecraft, mission personnel were required to work on a Mars day (24.65 h) for 78 days. This alien schedule presents a challenge to Earth-bound circadian physiology and a potential risk to workplace performance and safety. We evaluated the acceptability, feasibility, and effectiveness of a fatigue management program to facilitate synchronization with the Mars day and alleviate circadian misalignment, sleep loss, and fatigue. Operational field study. PML Science Operations Center. Scientific and technical personnel supporting PML mission. Sleep and fatigue education was offered to all support personnel. A subset (n = 19) were offered a short-wavelength (blue) light panel to aid alertness and mitigate/reduce circadian desynchrony. They were assessed using a daily sleep/work diary, continuous wrist actigraphy, and regular performance tests. Subjects also completed 48-h urine collections biweekly for assessment of the circadian 6-sulphatoxymelatonin rhythm. Most participants (87%) exhibited a circadian period consistent with adaptation to a Mars day. When synchronized, main sleep duration was 5.98 ± 0.94 h, but fell to 4.91 ± 1.22 h when misaligned (P Mars day suggests that future missions should utilize a similar circadian rhythm and fatigue management program to reduce the risk of sleepiness-related errors that jeopardize personnel safety and health during critical missions.

  7. Regional Landscape System Protection in the Urbanising Desert Southwest: Lessons from the Phoenix Metropolitan Region, USA

    Laura Musacchio

    2004-12-01

    Full Text Available Through the lens of holistic landscape ecology, the authors present for public consideration a desert landscape typology and plan assessment criteria. As a case study, historical trends in open space planning and two contrasting examples of recent open space plans from the Phoenix metropolitan area were analysed and compared to the typology in order to understand how successfully the open space planning efforts had addressed protection of the regional landscape system in the Sonoran Desert. We also developed an approach for the analysis of the landscape ecological component of plans that was based on Baer's general plan assessment criteria (1997. Our results indicate the desert landscape typology is a valuable step as part of a plan assessment of two regional, open space plans, but more importantly, the assessment criteria presented in this paper could be used as the foundation for a more thorough assessment method of the landscape ecological component of plans. The desert landscape typology and plan assessment criteria presented in this paper can be used to increase understanding about how the decision making of planners and designers has influenced the temporal and spatial dimensions of landscape legacies, trajectories and transformations, such as connectivity and fragmentation of open space.

  8. Profiling microRNA expression during multi-staged date palm (Phoenix dactylifera L.) fruit development

    Xin, Chengqi

    2015-01-29

    MicroRNAs (miRNAs) play crucial roles in multiple stages of plant development and regulate gene expression at posttranscriptional and translational levels. In this study, we first identified 238 conserved miRNAs in date palm (Phoenix dactylifera) based on a high-quality genome assembly and defined 78 fruit-development-associated (FDA) miRNAs, whose expression profiles are variable at different fruit development stages. Using experimental data, we subsequently detected 276 novel P. dactylifera-specific FDA miRNAs and predicted their targets. We also revealed that FDA miRNAs function mainly in regulating genes involved in starch/sucrose metabolisms and other carbon metabolic pathways; among them, 221 FDA miRNAs exhibit negative correlation with their corresponding targets, which suggests their direct regulatory roles on mRNA targets. Our data define a comprehensive set of conserved and novel FDA miRNAs along with their expression profiles, which provide a basis for further experimentation in assigning discrete functions of these miRNAs in P. dactylifera fruit development.

  9. Fine frequency tuning of the PHOENIX charge breeder used as a probe for ECRIS plasmas

    Lamy, T.; Angot, J.; Melanie, M.J.; Medard, J.; Sortais, P.; Thuillier, T.; Galata, A.; Koivisto, Hannu; Tarvainen, Olli

    2012-01-01

    Fine frequency tuning of ECR ion sources is a main issue to optimize the production of multiply charged ion beams. The PHOENIX charge breeder operation has been tested in the range 13.75 - 14.5 GHz with an HF power of about 400 W. The effect of this tuning is analyzed by measuring the multi-ionization efficiency obtained for various characterized injected 1+ ion beams (produced by the 2.45 GHz COMIC source). The 1+/n+ method includes the capture and the multi ionization processes of the 1+ beam and may be considered as a plasma probe. The n+ spectra obtained could be considered, in first approach, as an image of the plasma of the charge breeder. However, in certain conditions it has been observed that the injection of a few hundreds of nA of 1+ ions (i.e.: Xe+) in the plasma of the charge breeder, is able to destroy the charge state distribution of the support gas (i.e.: up to 40 % of O 6+ and O 7+ disappears). The study of this phenomenon will be presented along with plasma potential measurements for various charge states. This study may help to understand the creation (or destruction) of highly charged ions inside an ECRIS. The paper is followed by the slides of the presentation. (authors)

  10. AI applications in sheet metal forming

    Hussein, Hussein

    2017-01-01

    This book comprises chapters on research work done around the globe in the area of artificial intelligence (AI) applications in sheet metal forming. The first chapter offers an introduction to various AI techniques and sheet metal forming, while subsequent chapters describe traditional procedures/methods used in various sheet metal forming processes, and focus on the automation of those processes by means of AI techniques, such as KBS, ANN, GA, CBR, etc. Feature recognition and the manufacturability assessment of sheet metal parts, process planning, strip-layout design, selecting the type and size of die components, die modeling, and predicting die life are some of the most important aspects of sheet metal work. Traditionally, these activities are highly experience-based, tedious and time consuming. In response, researchers in several countries have applied various AI techniques to automate these activities, which are covered in this book. This book will be useful for engineers working in sheet metal industri...

  11. Dynamics of Radially Expanding Liquid Sheets

    Majumdar, Nayanika; Tirumkudulu, Mahesh S.

    2018-04-01

    The process of atomization often involves ejecting thin liquid sheets at high speeds from a nozzle that causes the sheet to flap violently and break up into fine droplets. The flapping of the liquid sheet has long been attributed to the sheet's interaction with the surrounding gas phase. Here, we present experimental evidence to the contrary and show that the flapping is caused by the thinning of the liquid sheet as it spreads out from the nozzle exit. The measured growth rates of the waves agree remarkably well with the predictions of a recent theory that accounts for the sheet's thinning but ignores aerodynamic interactions. We anticipate these results to not only lead to more accurate predictions of the final drop-size distribution but also enable more efficient designs of atomizers.

  12. Shape Optimization of Swimming Sheets

    Wilkening, J.; Hosoi, A.E.

    2005-03-01

    The swimming behavior of a flexible sheet which moves by propagating deformation waves along its body was first studied by G. I. Taylor in 1951. In addition to being of theoretical interest, this problem serves as a useful model of the locomotion of gastropods and various micro-organisms. Although the mechanics of swimming via wave propagation has been studied extensively, relatively little work has been done to define or describe optimal swimming by this mechanism.We carry out this objective for a sheet that is separated from a rigid substrate by a thin film of viscous Newtonian fluid. Using a lubrication approximation to model the dynamics, we derive the relevant Euler-Lagrange equations to optimize swimming speed and efficiency. The optimization equations are solved numerically using two different schemes: a limited memory BFGS method that uses cubic splines to represent the wave profile, and a multi-shooting Runge-Kutta approach that uses the Levenberg-Marquardt method to vary the parameters of the equations until the constraints are satisfied. The former approach is less efficient but generalizes nicely to the non-lubrication setting. For each optimization problem we obtain a one parameter family of solutions that becomes singular in a self-similar fashion as the parameter approaches a critical value. We explore the validity of the lubrication approximation near this singular limit by monitoring higher order corrections to the zeroth order theory and by comparing the results with finite element solutions of the full Stokes equations.

  13. Magnetic properties of sheet silicates

    Ballet, O.; Coey, J.M.D.

    1982-01-01

    Susceptibility, magnetisation and Moessbauer measurements are reported for a representative selection of 2:1 layer phyllosilicates. Eight samples from the mica, vermiculite and smectite groups include examples diluted in iron which are paramagnetic at all temperatures, as well as iron-rich silicates which order magnetically below 10 K. Anisotropic susceptibility of crystals of muscovite, biotite and vermiculite is quantitatively explained with a model where the Fe 2+ ions lie in sites of effective trigonal symmetry, the trigonal axis lying normal to the sheets. The ferrous ground state is an orbital singlet. Ferric iron gives an isotropic contribution to the susceptibility. Fe 2+ -Fe 2+ exchange interactions are ferromagnetic with Gapprox. equal to2 K, whereas Fe 3+ -Fe 3+ coupling is antiferromagnetic in the purely ferric minerals. A positive paramagnetic Curie temperature for glauconite may be attributable to Fe 2+ → Fe 3+ charge transfer. Magnetic order was found to set in inhomogeneously for glauconite at 1-7 K. One biotite sample showed an antiferromagnetic transition at Tsub(N) = 7 K marked by a well-defined susceptibility maximum. Its magnetic structure, consisting of ferromagnetic sheets with moments in their planes coupled antiferromagnetically by other, weak interactions, resembles that found earlier for the 1:1 mineral greenalite. (orig.)

  14. Effectiveness of Ti-micro alloying in relation to cooling rate on corrosion of AZ91 Mg alloy

    Candan, S.; Celik, M.; Candan, E.

    2016-01-01

    In this study, micro Ti-alloyed AZ91 Mg alloys (AZ91 + 0.5wt.%Ti) have been investigated in order to clarify effectiveness of micro alloying and/or cooling rate on their corrosion properties. Molten alloys were solidified under various cooling rates by using four stage step mold. The microstructural investigations were carried out by using scanning electron microscopy (SEM). Corrosion behaviors of the alloys were evaluated by means of immersion and electrochemical polarization tests in 3.5% NaCl solution. Results showed that the Mg 17 Al 12 (β) intermetallic phase in the microstructure of AZ91 Mg alloy formed as a net-like structure. The Ti addition has reduced the distribution and continuity of β intermetallic phase and its morphology has emerged as fully divorced eutectic. Compared to AZ91 alloy, the effect of the cooling rate in Ti-added alloy on the grain size was less pronounced. When AZ91 and its Ti-added alloys were compared under the same cooling conditions, the Ti addition showed notably high corrosion resistance. Electrochemical test results showed that while I corr values of AZ91 decrease with the increase in the cooling rate, the effect of the cooling rate on I corr values was much lower in the Ti-added alloy. The corrosion resistance of AZ91 Mg alloy was sensitive towards the cooling rates while Ti-added alloy was not affected much from the cooling conditions. - Highlights: • Effect the cooling rate on grain size was less pronounced in the Ti-added alloy. • The morphology of the β phase transformed into fully divorced eutectics. • Ti addition exhibited significantly higher corrosion resistance. • Ti micro alloying is more effective than faster cooling of the alloy on corrosion.

  15. The study of a Mg-rich epoxy primer for protection of AZ91D magnesium alloy

    Lu Xiangyu [School of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Zuo Yu, E-mail: zuoy@mail.buct.edu.c [School of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Zhao Xuhui; Tang Yuming; Feng Xingguo [School of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029 (China)

    2011-01-15

    Research highlights: {yields} A Mg-rich epoxy primer was prepared by adding pure magnesium particles in epoxy coating. Cross scratch testing results showed that in 3% NaCl solution the Mg-rich primer showed better protection for AZ91D magnesium alloy than the same epoxy primer without Mg addition. {yields} The open circuit potential of AZ91D alloy in NaCl solution decreased after coated with Mg-rich coating, suggesting that cathodic protection effect of the Mg-rich coating on AZ91D alloy was present. {yields} EIS studies showed that during the immersion tests of AZ91D alloy with Mg-rich coating the magnesium particles in coating dissolved with the charge-transfer resistance R{sub ct} at the magnesium particle/coating interface decreased and the double-layer capacitance Q{sub dl} increased. While the coating resistance remained stable for a long time and corrosion of the AZ91D alloy substrate was obviously delayed. - Abstract: A Mg-rich epoxy primer was prepared by adding pure magnesium particles to an epoxy coating. The coating properties were studied with electrochemical impedance spectroscopy (EIS), scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The Mg-rich primer showed better protection for AZ91D magnesium alloy than the same epoxy primer without Mg addition. The open circuit potential measurements showed cathodic protection effect of the Mg-rich primer on AZ91D alloy. Cross scratch testing showed that the Mg-rich primer provided better protection for the substrate than original epoxy coating. The precipitation of Mg(OH){sub 2} in the coating also provided some degree of barrier protection.

  16. Effects of sintering temperature on the corrosion behavior of AZ31 alloy with Ca–P sol–gel coating

    Niu, Bo [School of Materials Science and Engineering, Liaoning University of Technology, Jinzhou, Liaoning Province, 121001 (China); Shi, Ping, E-mail: p_shi@sohu.com [School of Materials Science and Engineering, Liaoning University of Technology, Jinzhou, Liaoning Province, 121001 (China); Wei, Donghua [School of Materials Science and Engineering, Liaoning University of Technology, Jinzhou, Liaoning Province, 121001 (China); E, Shanshan [School of Mathematics and Physics, Bohai University, Jinzhou, Liaoning Province, 121013 (China); Li, Qiang; Chen, Yang [School of Materials Science and Engineering, Liaoning University of Technology, Jinzhou, Liaoning Province, 121001 (China)

    2016-04-25

    To slow down the initial biodegradation rate of magnesium alloy, calcium phosphate (Ca–P) coatings were prepared on AZ31 magnesium alloy by a sol–gel technique. To study the effects of sintering temperature on microstructure, bonding strength and corrosion behavior of the coatings, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and an adhesive strength test were used to characterize the coatings. The corrosion resistance of the coatings was investigated by immersion test and electrochemical corrosion techniques in simulated body fluid (SBF) solution. It shows that the sol–gel coatings consist of Ca{sub 2}P{sub 2}O{sub 7}, mixture of Ca{sub 2}P{sub 2}O{sub 7}, Ca{sub 3}(PO{sub 4}){sub 2} and hydroxyapatite, and hydroxyapatite, by sintering respectively at 300 °C, 400 °C and 500 °C. There are major cracks on the coatings. The crack area portion on the coating and the bonding strength at the interface between the calcium phosphate coating and the bare AZ31 increases, and the corrosion resistance of the coated AZ31 in SBF decreases with increasing sintering temperatures from 300 °C to 500 °C. Based on our investigations, the corrosion resistance of the coated AZ31 in SBF depends mainly on the crack area portion on the coatings, rather than on the coating phase stability. - Highlights: • Ca–P coating was prepared on AZ31 alloy by a sol–gel technique. • Crack area portion in the coating increases with temperatures. • Bonding strength between Ca–P coating and substrate increases with temperatures. • Corrosion resistance of the coated AZ31 in SBF decreases with temperatures. • Corrosion resistance of the coated AZ31 depends mainly on the crack area portion.

  17. The study of a Mg-rich epoxy primer for protection of AZ91D magnesium alloy

    Lu Xiangyu; Zuo Yu; Zhao Xuhui; Tang Yuming; Feng Xingguo

    2011-01-01

    Research highlights: → A Mg-rich epoxy primer was prepared by adding pure magnesium particles in epoxy coating. Cross scratch testing results showed that in 3% NaCl solution the Mg-rich primer showed better protection for AZ91D magnesium alloy than the same epoxy primer without Mg addition. → The open circuit potential of AZ91D alloy in NaCl solution decreased after coated with Mg-rich coating, suggesting that cathodic protection effect of the Mg-rich coating on AZ91D alloy was present. → EIS studies showed that during the immersion tests of AZ91D alloy with Mg-rich coating the magnesium particles in coating dissolved with the charge-transfer resistance R ct at the magnesium particle/coating interface decreased and the double-layer capacitance Q dl increased. While the coating resistance remained stable for a long time and corrosion of the AZ91D alloy substrate was obviously delayed. - Abstract: A Mg-rich epoxy primer was prepared by adding pure magnesium particles to an epoxy coating. The coating properties were studied with electrochemical impedance spectroscopy (EIS), scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The Mg-rich primer showed better protection for AZ91D magnesium alloy than the same epoxy primer without Mg addition. The open circuit potential measurements showed cathodic protection effect of the Mg-rich primer on AZ91D alloy. Cross scratch testing showed that the Mg-rich primer provided better protection for the substrate than original epoxy coating. The precipitation of Mg(OH) 2 in the coating also provided some degree of barrier protection.

  18. Weld Repair of Thin Aluminum Sheet

    Beuyukian, C. S.; Mitchell, M. J.

    1986-01-01

    Weld repairing of thin aluminum sheets now possible, using niobium shield and copper heat sinks. Refractory niobium shield protects aluminum adjacent to hole, while copper heat sinks help conduct heat away from repair site. Technique limits tungsten/inert-gas (TIG) welding bombardment zone to melt area, leaving surrounding areas around weld unaffected. Used successfully to repair aluminum cold plates on Space Shuttle, Commercial applications, especially in sealing fractures, dents, and holes in thin aluminum face sheets or clad brazing sheet in cold plates, heat exchangers, coolers, and Solar panels. While particularly suited to thin aluminum sheet, this process also used in thicker aluminum material to prevent surface damage near weld area.

  19. Predicting Pulsar Scintillation from Refractive Plasma Sheets

    Simard, Dana; Pen, Ue-Li

    2018-05-01

    The dynamic and secondary spectra of many pulsars show evidence for long-lived, aligned images of the pulsar that are stationary on a thin scattering sheet. One explanation for this phenomenon considers the effects of wave crests along sheets in the ionized interstellar medium, such as those due to Alfvén waves propagating along current sheets. If these sheets are closely aligned to our line-of-sight to the pulsar, high bending angles arise at the wave crests and a selection effect causes alignment of images produced at different crests, similar to grazing reflection off of a lake. Using geometric optics, we develop a simple parameterized model of these corrugated sheets that can be constrained with a single observation and that makes observable predictions for variations in the scintillation of the pulsar over time and frequency. This model reveals qualitative differences between lensing from overdense and underdense corrugated sheets: Only if the sheet is overdense compared to the surrounding interstellar medium can the lensed images be brighter than the line-of-sight image to the pulsar, and the faint lensed images are closer to the pulsar at higher frequencies if the sheet is underdense, but at lower frequencies if the sheet is overdense.

  20. The Effects of Rare Earth Pr and Heat Treatment on the Wear Properties of AZ91 Alloy

    Ning Li

    2018-06-01

    Full Text Available This paper investigated the influences of Pr addition and heat treatment (T6 on the dry sliding wear behavior of AZ91 alloy. The wear rates and friction coefficients were measured by using a pin-on-disc tribometer under loads of 30, 60 and 90 N at dry sliding speeds of 100 rpm, over a sliding time of 15 min. The worn surfaces were examined using a scanning electron microscope and was analyzed with an energy dispersive spectrometer. The experimental results revealed that AZ91-1.0%Pr magnesium alloy exhibited lower wear rate and friction coefficient than the other investigated alloys. As the applied load increased, the wear rate and friction coefficient increased. Compared with the as-cast AZ91-1.0%Pr magnesium alloy, the hardness and wear resistance of the alloy after solution treatment were reduced, and through the subsequent aging, the hardness and wear resistance of the alloy were improved and the hardness was 101.1 HB (compared to as-cast AZ91 magnesium alloy, it increased by 45%. The AZ91-1.0%Pr with T6 magnesium alloy exhibited best wear resistance. Abrasion was dominant at load of 30 N, delamination was dominant at load of 60 N and plastic deformation was dominant at load of 90 N. Oxidation was observed at all loads.