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Sample records for affected zones haz

  1. Effect of Preweld Heat Treatment on the Microstructure of Heat-Affected Zone (HAZ) and Weldability of Inconel 939 Superalloy

    NASA Astrophysics Data System (ADS)

    González Albarrán, M. A.; Martínez, D. I.; Díaz, E.; Díaz, J. C.; Guzman, I.; Saucedo, E.; Guzman, A. Ma.

    2014-04-01

    The effect of two preweld heat treatments on the final microstructure of a heat-affected zone (HAZ) and its effect on the weldability of the superalloy Inconel 939 have been analyzed. The HAZ cracking related to the mechanical driving force criteria during the cooling cycle was directly influenced by the strain state at this zone. Heat treatments result in the formation of (1) irregular γ' precipitates (more negative misfits) which showed higher strain (high density of interfacial dislocations) and (2) spherical precipitates (near-zero misfits) which as a result of their structure improve weldability by reducing weld HAZ cracking considerably.

  2. Estimation of the most influential factors on the laser cutting process heat affected zone (HAZ) by adaptive neuro-fuzzy technique

    NASA Astrophysics Data System (ADS)

    Petković, Dalibor; Nikolić, Vlastimir; Milovančević, Miloš; Lazov, Lyubomir

    2016-07-01

    Heat affected zone (HAZ) of the laser cutting process may be developed on the basis on combination of different factors. In this investigation was analyzed the HAZ forecasting based on the different laser cutting parameters. The main aim in this article was to analyze the influence of three inputs on the HAZ of the laser cutting process. The method of ANFIS (adaptive neuro fuzzy inference system) was applied to the data in order to select the most influential factors for HAZ forecasting. Three inputs are considered: laser power, cutting speed and gas pressure. According the results the cutting speed has the highest influence on the HAZ forecasting (RMSE: 0.0553). Gas pressure has the smallest influence on the HAZ forecasting (RMSE: 0.0801). The results can be used in order to simplify HAZ prediction and analyzing.

  3. Microstructure characterization and weldability evaluation of the weld heat affected zone (HAZ) in 310HCbN tubing

    SciTech Connect

    Lundin, C.D.; Qiao, C.Y.P.

    1995-08-01

    Metallographic evaluation on the Gleeble simulated HAZ samples of 310HCbN tubing material was performed in order to reveal potential degradation in mechanical properties and corrosion resistance. The carbide evolutionary process in the HAZ samples was studied. It is indicated that 310HCbN material showed a weld HAZ sensitization tendency that is associated with the formation of Cr{sub 23}C{sub 6}.

  4. Relationship between crystallographic structure of the Ti{sub 2}O{sub 3}/MnS complex inclusion and microstructure in the heat-affected zone (HAZ) in steel processed by oxide metallurgy route and impact toughness

    SciTech Connect

    Xiong, Zhihui; Liu, Shilong; Wang, Xuemin; Shang, Chengjia; Misra, R.D.K.

    2015-08-15

    A new method based on electron back scattered diffraction (EBSD) is proposed to determine the structure of titanium oxide/MnS complex inclusion which induced the formation of intragranular acicular ferrite (IAF) in heat-affected zone (HAZ) in steel processed by oxide metallurgy route. It was found that the complex inclusion was Ti{sub 2}O{sub 3}/MnS, the orientation relationship between Ti{sub 2}O{sub 3} and MnS was also examined, and the crystallographic orientation relationship among IAF, Ti{sub 2}O{sub 3}/MnS complex inclusion, austenite, bainite formed at lower temperature is researched systematically. It was observed that MnS precipitated on Ti{sub 2}O{sub 3} at specific habit plane and direction and MnS had a specific orientation relationship ((0001) Ti{sub 2}O{sub 3}//(111) MnS), <10–10> Ti{sub 2}O{sub 3}//<110> MnS) with respect to Ti{sub 2}O{sub 3}. Intragranular acicular ferrite (IAF) nucleated on MnS part of the Ti{sub 2}O{sub 3}/MnS complex inclusion had no specific orientation relationship with MnS. IAF and the surrounding bainite had different Bain groups, so that there was an increase in high angle boundaries, which was beneficial for the toughness of HAZ. - Highlights: • The inclusion of TiO{sub x}/MnS that induced IAF formation is identified to be Ti{sub 2}O{sub 3}/MnS. • The inclusion is identified based on electron back scattered diffraction (EBSD). • MnS and Ti{sub 2}O{sub 3} had specific orientation relationship of Ti{sub 2}O{sub 3}/MnS complex inclusion. • The IAFs formed on the same inclusion tend to be in one Bain group. • IAF and the surrounding bainite tend to be in different Bain groups.

  5. Creep deformation and rupture behavior of 2.25Cr-1Mo steel weldments and its constituents (base metal, weld metal and simulated heat affected zones)

    SciTech Connect

    Laha, K.; Chandravathi, K.S.; Rao, K.B.S.; Mannan, S.L.

    1995-12-31

    Microstructure across a weldment base metal through transformed heat-affected zone (HAZ) to cast weld metal. HAZ of 2.25Cr-1Mo weldment consists of coarse-grain bainite, fine-grain bainite and intercritical region. These HAZ microstructures were simulated by isothermal heat-treatments. Creep tests were carried out on base metal, weld metal, weldment and the simulated HAZ structures. Creep deformation and fracture behavior of 2.25Cr-1Mo weldments has been assessed based on the properties of its constituents. Coarse-grain bainite with low ductility and intercritical structure with low strength are the critical components of HAZ determining performance of the weldments.

  6. SCC Initiation in Alloy 600 Heat Affected Zones Exposed to High Temperature Water

    SciTech Connect

    E Richey; DS Morton; RA Etien; GA Young; RB Bucinell

    2006-11-03

    Studies have shown that grain boundary chromium carbides improve the stress corrosion cracking (SCC) resistance of nickel based alloys exposed to high temperature, high purity water. However, thermal cycles from welding can significantly alter the microstructure of the base material near the fusion line. In particular, the heat of welding can solutionize grain boundary carbides and produce locally high residual stresses and strains, reducing the SCC resistance of the Alloy 600 type material in the heat affected zone (HAZ). Testing has shown that the SCC growth rate in Alloy 600 heat affected zone samples can be {approx}30x faster than observed in the Alloy 600 base material under identical testing conditions due to fewer intergranular chromium rich carbides and increased plastic strain in the HAZ [1, 2]. Stress corrosion crack initiation tests were conducted on Alloy 600 HAZ samples at 360 C in hydrogenated, deaerated water to determine if these microstructural differences significantly affect the SCC initiation resistance of Alloy 600 heat affected zones compared to the Alloy 600 base material. Alloy 600 to EN82H to Alloy 600 heat-affected-zone (HAZ) specimens where fabricated from an Alloy 600 to Alloy 600 narrow groove weld with EN82H filler metal. The approximate middle third of the specimen gauge region was EN82H such that each specimen had two HAZ regions. Tests were conducted with in-situ monitored smooth tensile specimens under a constant load, and a direct current electric potential drop was used for in-situ detection of SCC. Test results suggest that the SCC initiation resistance of Alloy 600 and its weld metal follows the following order: EN82H > Alloy 600 HAZ > Alloy 600. The high SCC initiation resistance observed to date in Alloy 600 heat affected zones compared to wrought Alloy 600 is unexpected based on the microstructure of HAZ versus wrought material and based on prior SCC growth rate studies. The observed behavior for the HAZ specimens is likely

  7. Effects of Notch Location on Heat-affected Zone Impact Properties of SA-516 Steels

    NASA Astrophysics Data System (ADS)

    Hong, Jaekeun; Park, Jihong; Kang, Chungyun

    In case of welding for pressure retaining parts on nuclear components, the verifications of heat affected zone (HAZ) impact properties are required according to application codes such as ASME Sec. III, RCC-M, KEPIC (Korea Electric Power Industry Code) MN, and JEA (Japan Electric Association) Code. Especially in case of Charpy V-notch tests of HAZ, the requirements of notch location and specimen direction have greatly impact on the reliability and consistency of the test results. For the establishment of newly adequate impact test requirements, the requirements about the HAZ impact tests of ASME Section III, RCC-M, KEPIC MN and JEA code were researched in this study. And also the HAZ impact test requirements about surveillance tests in nuclear reactor vessels were compared and investigated. For the effects of the notch location and specimen direction on the impact properties, SA-516 Gr.70 materials were investigated. The specimens were fabricated with using shielded metal-arc welding, and maximum heat inputs were controlled within the range of 16˜27 kJ/cm. Especially, this research showed the lateral expansion values and absorbed energies were not compatible and the impact test results were varied depending on notch location and specimen direction. Based on this study, newly adequate impact test requirements of HAZ were proposed.

  8. TEM observation of the heat-affected zone in electron beam welded superalloy Inconel 713C

    SciTech Connect

    Lachowicz, Maciej Dudzinski, Wlodzimierz; Podrez-Radziszewska, Marzena

    2008-05-15

    The paper presents results of microstructural observations and phase analysis of electron-beam-welded fusion zones in superalloy Inconel 713C using transmission electron microscopy. In the fusion zone, a 90% fraction of fine-grained {gamma}' precipitates was found, with sizes up to 30 nm. No dislocations were observed in the precipitates or at the {gamma}-{gamma}' interface. Primary, undissolved inclusions of {gamma}' were found in the heat-affected zone (HAZ). In the HAZ, a very high concentration of dislocations was found at the {gamma}-{gamma}' boundaries, as well as inside the {gamma}' particles and in the {gamma} solid solution. The increased dislocation density indicates loss of coherence of that phase and the creation of a semi-coherent boundary, and is related to dissolution of the particles and intensified diffusion through the interphase {gamma}-{gamma}' boundary. The lattice misfit coefficient {delta}a/a between the {gamma}' particles and {gamma} solution in the HAZ indicates negative values from - 0.20% to - 0.06%. The presence of semi-coherent boundaries and the negative lattice misfit coefficient leads to dislocation locking and can result in cracking in the HAZ.

  9. Characteristics of GTA fusion zones and heat affected zones in superalloy 713C

    NASA Astrophysics Data System (ADS)

    Lachowicz, M. B.; Dudziński, W.

    2012-09-01

    In this paper, metallographic examinations, characterising microstructural changes in the 713C superalloy subjected to remelting by GTA method, are presented. In the fusion zone, precipitation of M23C6 or M6C carbides based on chromium and molybdenum was observed. Eutectic mixtures of ( γ- gg')-M x C y type with highly developed morphology were also perceived. It was found that, in the matrix areas with non-homogeneous chemical composition, the eutectic reaction γ-γ' can occur at the temperature close to that of the precipitation of the M x C y carbides. The presence of silicon in the carbide phases can be conducive to lowering their solidification point by creating low-melting compound NbSi. Both in the fusion zone (FZ) and in the heat-affected zone (HAZ), the secondary precipitates of the Ni3(AlTi)- γ' phase, varying in size from 50 to 100 nm, were found. The lattice mismatch factor of the γ and γ' particles was +0.48 % to +0.71 %, which is characteristic of the coherent precipitates of the Ni3Al phase enriched with titanium. No dislocations or stacking faults were observed in the microstructure of the FZ. In the HAZ, some primary undissolved γ' precipitates, with a part of aluminium probably replaced with niobium were observed, which raised their melting point.

  10. Mechanical Properties and Microstructures of the HAZs of 11Cr F/M Steel for Gen-IV Nuclear Power Station

    NASA Astrophysics Data System (ADS)

    Li, Yongkui; Wang, Jian; Lu, Shanping; Rong, Lijian; Li, Dianzhong

    2015-02-01

    The weldability of a newly developed 11Cr ferritic/martensitic (F/M) steel to be used in Pb-Bi liquid cooled ADS for the fourth generation nuclear power station was studied by experiments and numerical simulation. In this work, an appropriate method for obtaining simulated heat-affected zones (HAZs) was developed. HAZs, including CG-HAZ, FG-HAZ, and IC-HAZ, were successfully simulated by Gleeble at heating rates of 209, 176, and 149 °C/s and peak temperatures of 1314, 1138, and 998 °C, respectively. Results of tension and impact tests indicated that the simulated HAZs had much higher strength and poorer toughness than the base metal. The poor toughness is caused by high carbon, silicon contents, and quenched martensitic microstructures. The tempering treatment is necessary for the developed steel before application in nuclear reactor.

  11. Development of Texture from the HAZ to Weldmetal Across the Fusion Boundary

    NASA Astrophysics Data System (ADS)

    Strangwood, Martin; Davis, Claire L.

    The textures and grain sizes within the heat affected zone (HAZ) and weldmetal regions of single phase bcc (Fe-3 wt% Si; 430 stainless steel) and fcc (AA5182 and 5251) alloys in spot and metal inert gas (MIG) welds have been determined using electron back-scattered diffraction (EBSD); optical and scanning electron microscopy (SEM) techniques. In all the situations studied, the grains that developed into the columnar weldmetal grains from the HAZ had a misorientation of less than 10° between <100> and the maximum thermal gradient (∇Tmax). The initial weldmetal columnar grain width can be related to the HAZ grain diameter at the fusion boundary by a simple relationship involving the proportion of grains with the favourable low misorientation texture in weldmetal and HAZ. This relationship does not hold throughout the whole weldmetal region due to competitive growth between columnar grains (steel) and a columnar-to-equiaxed transition (CET; Al-based alloys).

  12. Precipitate microstructures and resulting properties of Al-Zn-Mg metal inert gas-weld heat-affected zones

    NASA Astrophysics Data System (ADS)

    Nicolas, M.; Deschamps, A.

    2004-05-01

    Using the combination of small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM), the precipitate microstructure is quantitatively investigated in the heat-affected zones (HAZs) of Al-Zn-Mg metal inert gas (MIG)-welds, and the resulting mechanical properties are determined by hardness measurements. Three initial states prior to welding (T4, T6, and T7) are investigated, and the subsequent microstructure evolution during natural aging and postwelding heat treatments (PWHTs) is assessed. The critical part of the HAZ is shown to be the transition region where partial dissolution of the initially present precipitates occurs. In this transition zone, precipitate coarsening is shown to occur for the T6 and T7 initial states, contrarily to the T4 material. After PWHT, the T6 and T7 materials experience a weak region related to this coarsening behavior, whereas the T4 material HAZ is able to recover a homogeneous microstructure after a suitably chosen PWHT. Simple model ramp heat treatments are shown to describe the main phenomena involved in the HAZ. Finally, a precipitation hardening model is successfully applied to the microstructural data to describe the hardness profiles in the various HAZs.

  13. Microstructural response to heat affected zone cracking of prewelding heat-treated Inconel 939 superalloy

    SciTech Connect

    Gonzalez, M.A.; Garza, A.

    2011-12-15

    The microstructural response to cracking in the heat-affected zone (HAZ) of a nickel-based IN 939 superalloy after prewelding heat treatments (PWHT) was investigated. The PWHT specimens showed two different microstructures: 1) spherical ordered {gamma} Prime precipitates (357-442 nm), with blocky MC and discreet M{sub 23}C{sub 6} carbides dispersed within the coarse dendrites and in the interdendritic regions; and 2) ordered {gamma} Prime precipitates in 'ogdoadically' diced cube shapes and coarse MC carbides within the dendrites and in the interdendritic regions. After being tungsten inert gas welded (TIG) applying low heat input, welding speed and using a more ductile filler alloy, specimens with microstructures consisting of spherical {gamma} Prime precipitate particles and dispersed discreet MC carbides along the grain boundaries, displayed a considerably improved weldability due to a strong reduction of the intergranular HAZ cracking associated with the liquation microfissuring phenomena. - Highlights: Black-Right-Pointing-Pointer Homogeneous microstructures of {gamma} Prime spheroids and discreet MC carbides of Ni base superalloys through preweld heat treatments. Black-Right-Pointing-Pointer {gamma} Prime spheroids and discreet MC carbides reduce the intergranular HAZ liquation and microfissuring of Nickel base superalloys. Black-Right-Pointing-Pointer Microstructure {gamma} Prime spheroids and discreet blocky type MC carbides, capable to relax the stress generated during weld cooling. Black-Right-Pointing-Pointer Low welding heat input welding speeds and ductile filler alloys reduce the HAZ cracking susceptibility.

  14. Mechanical Properties of Heat Affected Zone of High Strength Steels

    NASA Astrophysics Data System (ADS)

    Sefcikova, K.; Brtnik, T.; Dolejs, J.; Keltamaki, K.; Topilla, R.

    2015-11-01

    High Strength Steels became more popular as a construction material during last decade because of their increased availability and affordability. On the other hand, even though general use of Advanced High Strength Steels (AHSS) is expanding, the wide utilization is limited because of insufficient information about their behaviour in structures. The most widely used technique for joining steels is fusion welding. The welding process has an influence not only on the welded connection but on the area near this connection, the so-called heat affected zone, as well. For that reason it is very important to be able to determine the properties in the heat affected zone (HAZ). This area of investigation is being continuously developed in dependence on significant progress in material production, especially regarding new types of steels available. There are currently several types of AHSS on the world market. Two most widely used processes for AHSS production are Thermo-Mechanically Controlled Processing (TMCP) and Quenching in connection with Tempering. In the presented study, TMCP and QC steels grade S960 were investigated. The study is focused on the changes of strength, ductility, hardness and impact strength in heat affected zone based on the used amount of heat input.

  15. Initial Evaluation of the Heat-Affected Zone, Local Embrittlement Phenomenon as it Applies to Nuclear Reactor Vessels

    SciTech Connect

    McCabe, D.E.

    1999-09-01

    The objective of this project was to determine if the local brittle zone (LBZ) problem, encountered in the testing of the heat-affected zone (HAZ) part of welds in offshore platform construction, can also be found in reactor pressure vessel (RPV) welds. Both structures have multipass welds and grain coarsening along the fusion line. Literature was obtained that described the metallurgical evidence and the type of research work performed on offshore structure welds.

  16. Cleavage initiation in the intercritically reheated coarse-grained heat affected zone. Part 2: Failure criteria and statistical effects

    SciTech Connect

    Davis, C.L.; King, J.E.

    1996-10-01

    In part 1 of this article, cleavage initiation in the intercritically reheated coarse-grained heat affected zone (IC CG HAZ) of high-strength low-alloy (HSLA) steels was determined to occur between two closely spaced blocky MA particles. Blunt notch, crack tip opening displacement (CTOD), and precracked Charpy testing were used in this investigation to determine the failure criteria required for cleavage initiation to occur by this mechanism in the IC CG HAZ. It was found that the attainment of a critical level of strain was required in addition to a critical level of stress. This does not occur in the case of high strain rate testing, for example, during precracked Charpy testing. A different cleavage initiation mechanism is then found to operate. The precise fracture criteria and microstructural requirements (described in part 1 of this article) result in competition between potential cleavage initiation mechanisms in the IC CG HAZ.

  17. Liquation Microfissuring in the Weld Heat-Affected Zone of an Overaged Precipitation-Hardened Nickel-Base Superalloy

    NASA Astrophysics Data System (ADS)

    Ojo, O. A.; Chaturvedi, M. C.

    2007-02-01

    The effect of preweld overaging heat treatment on the microstructural response in the heat-affected zone (HAZ) of a precipitation-hardened nickel-base superalloy INCONEL 738LC subjected to the welding thermal cycle ( i.e., rapid) was investigated. The overaging heat treatment resulted in the formation of an interfacial microconstituent containing M23X6 particles and coarsening of primary and secondary γ' precipitates. The HAZ microstructures around welds in the overaged alloy were simulated using the Gleeble thermomechanical simulation system. Microstructural examination of simulated HAZs and those present in tungsten inert gas (TIG) welded specimens showed the occurrence of extensive grain boundary liquation involving liquation reaction of the interfacial microconstituents containing M23X6 particles and MC-type carbides. In addition, the coarsened γ' precipitate particles present in the overaged alloy persisted well above their solvus temperature to temperatures where they constitutionally liquated and contributed to considerable liquation of grain boundaries, during continuous rapid heating. Intergranular HAZ microfissuring, with resolidified product formed mostly on one side of the microfissures, was observed in welded specimens. This suggested that the HAZ microfissuring generally occurred by decohesion across one of the solid-liquid interfaces during the grain boundary liquation stage of the weld thermal cycle. Correlation of simulated HAZ microstructures with hot ductility properties of the alloy revealed that the temperature at which the alloy exhibited zero ductility during heating was within the temperature range at which grain boundary liquation was observed. The on-cooling ductility of the alloy was significantly damaged by the on-heating liquation reaction, as reflected by the considerably low ductility recovery temperature (DRT). Important characteristics of the intergranular liquid that could influence HAZ microfissuring of the alloy in overaged

  18. Effect of boron segregation at grain boundaries on heat-affected zone cracking in wrought INCONEL 718

    NASA Astrophysics Data System (ADS)

    Chen, W.; Chaturvedi, M. C.; Richards, N. L.

    2001-04-01

    Susceptibility to heat-affected zone (HAZ) cracking during electron-beam welding was studied in two INCONEL 718-based alloys doped with different levels of boron. By lowering the carbon, sulfur, and phosphorous concentrations to be “as low as possible,” the occurrence of HAZ cracking was related directly to the level of segregation of boron at grain boundaries, which occurred by nonequilibrium segregation during a preweld heat treatment. The study has demonstrated a direct correlation between the amount of boron segregated at grain boundaries and their susceptibility to HAZ cracking, in terms of the total crack length and number of cracks observed in the HAZ. The analysis of results suggests that both the melting and resolidification temperatures of the boron-segregated grain boundaries can be about 100 °C to 200 °C lower than those of the grain boundaries that were susceptible to constitutional liquation of Nb carbides on them, making boron more deleterious in causing HAZ cracking.

  19. Corrosion behavior in high heat input welded heat-affected zone of Ni-free high-nitrogen Fe–18Cr–10Mn–N austenitic stainless steel

    SciTech Connect

    Moon, Joonoh Ha, Heon-Young; Lee, Tae-Ho

    2013-08-15

    The pitting corrosion and interphase corrosion behaviors in high heat input welded heat-affected zone (HAZ) of a metastable high-nitrogen Fe–18Cr–10Mn–N austenitic stainless steel were explored through electrochemical tests. The HAZs were simulated using Gleeble simulator with high heat input welding condition of 300 kJ/cm and the peak temperature of the HAZs was changed from 1200 °C to 1350 °C, aiming to examine the effect of δ-ferrite formation on corrosion behavior. The electrochemical test results show that both pitting corrosion resistance and interphase corrosion resistance were seriously deteriorated by δ-ferrite formation in the HAZ and their aspects were different with increasing δ-ferrite fraction. The pitting corrosion resistance was decreased by the formation of Cr-depleted zone along δ-ferrite/austenite (γ) interphase resulting from δ-ferrite formation; however it didn't depend on δ-ferrite fraction. The interphase corrosion resistance depends on the total amount of Cr-depleted zone as well as ferrite area and thus continuously decreased with increasing δ-ferrite fraction. The different effects of δ-ferrite fraction on pitting corrosion and interphase corrosion were carefully discussed in terms of alloying elements partitioning in the HAZ based on thermodynamic consideration. - Highlights: • Corrosion behavior in the weld HAZ of high-nitrogen austenitic alloy was studied. • Cr{sub 2}N particle was not precipitated in high heat input welded HAZ of tested alloy. • Pitting corrosion and interphase corrosion show a different behavior. • Pitting corrosion resistance was affected by whether or not δ-ferrite forms. • Interphase corrosion resistance was affected by the total amount of δ-ferrite.

  20. Analysis of weldability testing techniques for HAZ liquation cracking

    NASA Astrophysics Data System (ADS)

    Lin, Wangen; Lippold, John C.; Baeslack, William A., III

    A new methodology for quantifying heat-affected zone (HAZ) liquation cracking susceptibility has been developed by considering the temperature-dependent, hot ductility of a material during welding in the context of current liquation cracking theories. This methodology defines a temperature field in the HAZ surrounding the weld pool, termed the thermal crack susceptible region (CSR) in which liquation cracking may occur. The thermal CSR is material-specific and represents a metallurgically-based quantification of weldability. Using this method, weldability test results can be more easily applied to actual welding conditions. This paper describes how this methodology can be utilized in conjunction with three widely used weldability testing techniques, namely, the Gleeble hot ductility test, and the spot and longitudinal type Varestraint tests. The method of data interpretation is addressed for each test technique and correlations among test techniques described.

  1. Crack growth rates of irradiated austenitic stainless steel weld heat affected zone in BWR environments.

    SciTech Connect

    Chopra, O. K.; Alexandreanu, B.; Gruber, E. E.; Daum, R. S.; Shack, W. J.; Energy Technology

    2006-01-31

    Austenitic stainless steels (SSs) are used extensively as structural alloys in the internal components of reactor pressure vessels because of their superior fracture toughness. However, exposure to high levels of neutron irradiation for extended periods can exacerbate the corrosion fatigue and stress corrosion cracking (SCC) behavior of these steels by affecting the material microchemistry, material microstructure, and water chemistry. Experimental data are presented on crack growth rates of the heat affected zone (HAZ) in Types 304L and 304 SS weld specimens before and after they were irradiated to a fluence of 5.0 x 10{sup 20} n/cm{sup 2} (E > 1 MeV) ({approx} 0.75 dpa) at {approx}288 C. Crack growth tests were conducted under cycling loading and long hold time trapezoidal loading in simulated boiling water reactor environments on Type 304L SS HAZ of the H5 weld from the Grand Gulf reactor core shroud and on Type 304 SS HAZ of a laboratory-prepared weld. The effects of material composition, irradiation, and water chemistry on growth rates are discussed.

  2. Effect of welding parameters on the heat-affected zone of AISI409 ferritic stainless steel

    NASA Astrophysics Data System (ADS)

    Ranjbarnodeh, Eslam; Hanke, Stefanie; Weiss, Sabine; Fischer, Alfons

    2012-10-01

    One of the main problems during the welding of ferritic stainless steels is severe grain growth within the heat-affected zone (HAZ). In the present study, the microstructural characteristics of tungsten inert gas (TIG) welded AISI409 ferritic stainless steel were investigated by electron backscattered diffraction (EBSD), and the effects of welding parameters on the grain size, local misorientation, and low-angle grain boundaries were studied. A 3-D finite element model (FEM) was developed to predict the effects of welding parameters on the holding time of the HAZ above the critical temperature of grain growth. It is found that the base metal is not fully recrystallized. During the welding, complete recrystallization is followed by severe grain growth. A decrease in the number of low-angle grain boundaries is observed within the HAZ. FEM results show that the final state of residual strains is caused by competition between welding plastic strains and their release by recrystallization. Still, the decisive factor for grain growth is heat input.

  3. Notch position in the HAZ specimen of reactor pressure vessel steel

    NASA Astrophysics Data System (ADS)

    Kim, J. H.; Yoon, E. P.

    1998-12-01

    Variations in the notch toughness in the heat-affected zone (HAZ) were investigated by positioning the Charpy V-notches along the line normal to the weld fusion line of a SA 508 Cl.3 reactor pressure vessel (RPV) steel. In the notch position for common surveillance HAZ specimens, rather higher toughness values were acquired. The minimum properties were noted in the region of 4-5 mm apart from the fusion boundary, where the values of toughness and strength were both poorer than those of the other regions of the HAZ and the base metal. The causes for these variations were discussed with reference to the microstructures from the actual and the simulated welding processes.

  4. Evaluation of Heat-affected Zone Hydrogen-induced Cracking in High-strength Steels

    NASA Astrophysics Data System (ADS)

    Yue, Xin

    Shipbuilding is heavily reliant on welding as a primary fabrication technique. Any high performance naval steel must also possess good weldability. It is therefore of great practical importance to conduct weldability testing of naval steels. Among various weldability issues of high-strength steels, hydrogen-induced cracking (HIC) in the heat-affected zone (HAZ) following welding is one of the biggest concerns. As a result, in the present work, research was conducted to study the HAZ HIC susceptibility of several naval steels. Since the coarse-grained heat-affected zone (CGHAZ) is generally known to be the most susceptible to HIC in the HAZ region, the continuous cooling transformation (CCT) behavior of the CGHAZ of naval steels HSLA-65, HSLA-100, and HY-100 was investigated. The CGHAZ microstructure over a range of cooling rates was characterized, and corresponding CCT diagrams were constructed. It was found that depending on the cooling rate, martensite, bainite, ferrite and pearlite can form in the CGHAZ of HSLA-65. For HSLA-100 and HY-100, only martensite and bainite formed over the range of cooling rates that were simulated. The constructed CCT diagrams can be used as a reference to select welding parameters to avoid the formation of high-hardness martensite in the CGHAZ, in order to ensure resistance to hydrogen-induced cracking. Implant testing was conducted on the naval steels to evaluate their susceptibility to HAZ HIC. Stress vs. time to failure curves were plotted, and the lower critical stress (LCS), normalized critical stress ratio (NCSR) and embrittlement index (EI) for each steel were determined, which were used to quantitatively compare HIC susceptibility. The CGHAZ microstructure of the naval steels was characterized, and the HIC fracture behavior was studied. Intergranular (IG), quasi-cleavage (QC) and microvoid coalescence (MVC) fracture modes were found to occur in sequence during the crack initiation and propagation process. This was

  5. Effect of microstructures on magnetic Barkhausen noise level in the weld HAZ of an RPV steel

    NASA Astrophysics Data System (ADS)

    Kim, Joo-Hag; Park, Duck-Gun; Ok, Chi-Il; Yoon, Eui-Pak; Hong, Jun-Hwa

    1999-05-01

    Microstructural state and magnetic Barkhausen noise (BN) level have been correlated in the weld heat-affected zone (HAZ) of a pressure vessel steel. The BN level increased with increasing size of carbide, and the tempered bainite structure showed higher BN signal than the tempered martensite. The results indicated that heat-treated materials may result in microstructurally different domain wall pinning obstacles at different thermal cycles.

  6. Microstructure and property examination of the weld HAZ in Grade 100 microalloyed steel

    NASA Astrophysics Data System (ADS)

    Poorhaydari-Anaraki, Kioumars

    The microstructure and mechanical property variations across different regions of the heat-affected zone (HAZ) of a Grade 100 microalloyed steel were examined for a range of heat inputs from 0.5 to 2.5 kJ/mm. Autogenous gas tungsten arc welding was performed on plates of Grade 100 steel to create the HAZ. The weld thermal cycles were recorded by embedding thermocouples at different locations in the plates. Examination of precipitate alterations (dissolution, coarsening and reprecipitation) was carried out theoretically and/or experimentally using transmission electron microscopy (TEM). Iron matrix phase transformations and grain size changes were examined with optical microscopy as well as TEM (both thin foils and carbon replicas). Hardness measurements (macro-, micro- and nano-hardness) were mainly used for examination of mechanical properties across the HAZ. Hardness measurements across the HAZ showed hardening in 0.5 kJ/mm weld samples and softening in the 1.5 and 2.5 kJ/mm weld samples. This was mainly due to the difference in cooling rates, since fast cooling results in microstructures with finer structures (especially grain size) and higher levels of solutes and sub-structure in the matrix. The coarse-grained HAZ (CGHAZ) had a higher hardness relative to the fine-grained HAZ (FGHAZ), regardless of the heat input, due to the formation of bainitic and martensitic fine structures (laths/plates) inside large prior austenite grains. The CGHAZ-0.5 kJ/mm consisted of packets of untempered lath martensite and coarse regions of autotempered martensite or aged massive ferrite. Increasing the heat input to 1.5 and 2.5 kJ/mm resulted in mainly bainitic microstructures (e.g., granular bainite) with some acicular ferrite and grain-boundary ferrite in the CGHAZ. The FGHAZ was mainly made up of polygonal ferrite, with considerable amounts of bainitic ferrite in the case of the 0.5 kJ/mm weld sample. Nb-rich carbides mostly survived the thermal cycles experienced in FGHAZ

  7. Effect of homogenization heat treatment on the microstructure and heat- affected zone microfissuring in welded cast alloy 718

    NASA Astrophysics Data System (ADS)

    Huang, Xiao; Chaturvedi, M. C.; Richards, N. L.

    1996-03-01

    The effect of homogenization temperature on microfissuring in the heat-affected zones of electronwelded cast INCONEL 718 has been studied. The material was homogenized at various temperatures in the range of 1037 ° to 1163 ° and air-cooled. The homogenized material was then electron-beam welded by the bead-on-plate welding technique. The microstructures and microfissuring in the heat-affected zone (HAZ) were evaluated by analytical scanning electron microscopy (SEM). The grain boundary segregation of various elements was evaluated by secondary ion mass spectroscopy (SIMS). It was observed that the total crack length (TCL) of microfissures first decreases with homogenization temperature and then increases, with a minimum occurring in the specimen heat treated at 1163 °. This trend coincides with the variation in segregation of B at grain boundaries with homogenization temperature and has been explained by equilibrium and nonequilibrium segregation of B to grain boundaries during the homogenization heat treatment. No other element was observed to segregate at the grain boundaries. The variation in volume fraction of phases like δ-Ni3Nb, MC carbide, and Laves phases does not follow the same trend as that observed for TCL and B segregation at the grain boundaries. Therefore, microfissuring in HAZ of welded cast INCONEL 718 is attributed to the segregation of B at the grain boundaries.

  8. Effects of Oxides on Tensile and Charpy Impact Properties and Fracture Toughness in Heat Affected Zones of Oxide-Containing API X80 Linepipe Steels

    NASA Astrophysics Data System (ADS)

    Sung, Hyo Kyung; Sohn, Seok Su; Shin, Sang Yong; Oh, Kyung Shik; Lee, Sunghak

    2014-06-01

    This study is concerned with effects of complex oxides on acicular ferrite (AF) formation, tensile and Charpy impact properties, and fracture toughness in heat affected zones (HAZs) of oxide-containing API X80 linepipe steels. Three steels were fabricated by adding Mg and O2 to form oxides, and various HAZ microstructures were obtained by conducting HAZ simulation tests under different heat inputs. The no. of oxides increased with increasing amount of Mg and O2, while the volume fraction of AF present in the steel HAZs increased with increasing the no. of oxides. The strengths of the HAZ specimens were generally higher than those of the base metals because of the formation of hard microstructures of bainitic ferrite and granular bainite. When the total Charpy absorbed energy was divided into the fracture initiation and propagation energies, the fracture initiation energy was maintained constant at about 75 J at room temperature, irrespective of volume fraction of AF. The fracture propagation energy rapidly increased from 75 to 150 J and saturated when the volume fraction of AF exceeded 30 pct. At 253 K (-20 °C), the total absorbed energy increased with increasing volume fraction of AF, as the cleavage fracture was changed to the ductile fracture when the volume fraction of AF exceeded 45 pct. Thus, 45 vol pct of AF at least was needed to improve the Charpy impact energy, which could be achieved by forming a no. of oxides. The fracture toughness increased with increasing the no. of oxides because of the increased volume fraction of AF formed around oxides. The fracture toughness did not show a visible correlation with the Charpy absorbed energy at room temperature, because toughness properties obtained from these two toughness testing methods had different significations in view of fracture mechanics.

  9. In-situ Phase transformation study in fine grained heat affected zone of Grade 91 steels

    SciTech Connect

    Babu, Sudarsanam Suresh; Yamamoto, Yukinori; Santella, Michael L; Yu, Xinghua; Komizo, Prof. Y; Terasaki, Prof. H

    2014-01-01

    Creep strength-enhanced ferritic (CSEF) steels such as the 9 Cr steel [ASTM A387 Grade 91] are widely used as tubing and piping in the new generation of fossil fired power plants. Microstructures in the fine-grained heat affected zone (FGHAZ) may significantly reduce creep strength leading Type IV failures. Current research suggest that reducing pre-weld tempering temperature from 760 C (HTT) to 650 C (LTT) has the potential to double the creep life of these welds. To understand this improvement, time-resolved X-ray diffraction (TRXRD) measurement with synchrotron radiation was used to characterize the microstructure evolution during fine grained heat-affected zone (HAZ) thermal cycling of grade 91 steel. The measurements showed both M23C6 (M=Fe, Cr) and MX (M=Nb, V; X=C,N) are present in the sample after the HTT condition. Near equilibrium fraction of M23C6 was measured in high temperature tempering condition (HTT, 760 C). However, the amount of M23C6 in LTT condition was very low since the diffraction peaks are close to the background. During simulated FGHAZ thermal cycling, the M23C6 partially dissolved in HTT sample. Interestingly, MX did not dissolve in both LTT and HTT samples. Hypothesis for correlation of M23C6 carbide distribution and pre-mature creep failure in FGHAZ will be made.

  10. Low-Temperature Sensitization Behavior of Base, Heat-Affected Zone, and Weld Pool in AISI 304LN

    NASA Astrophysics Data System (ADS)

    Singh, Raghuvir; Das, Gautam; Singh, P. K.; Chattoraj, I.

    2009-05-01

    Present investigations were focused on low-temperature sensitization (LTS) behavior of 304LN stainless steels considered from pipes of two different thicknesses. The specimens for the present study were taken from solution-annealed pipes (of varying thicknesses) and welded pipes (including the heat-affected zone (HAZ)). The specimens were subjected to thermal aging at 400 °C and 450 °C for different durations ranging from 125 to 8000 hours, to evaluate their sensitization susceptibility. The aging durations were worked out to simulate the 30-to-100-year life of the studied stainless steel at 300 °C using the Arrheneous equation and considering the activation energy of 150 kJ/mol. The thermally aged specimens were characterized for their degree of sensitization (DOS) and susceptibility to intergranular corrosion (IGC) by double-loop (DL) electrochemical potentiokinetic reactivation (EPR) and by methods given in the ASTM A262 practices A and E. It has been clearly shown that the weld pool is more sensitive to IGC than are the base and the HAZ at both the aging temperatures (LTS), because they showed IGC cracks during the bending subsequent to the boiling in H2SO4-CuSO4 solution. Both the base and the HAZ of the thicker pipe material showed susceptibility to sensitization, as indicated by the increasing DOS and “dual-type” microstructure during electrolytic oxalic acid (EOA) etching; however, they were found safe from IGC for the studied sensitization times. The susceptibility to sensitization and IGC in the weld pool is related to the presence of copious delta ferrite with chromium diffusivity that is accelerated compared to the austenite phase. The time-temperature-sensitization (TTS) curves were prepared accordingly, based on these results.

  11. The use of supercomputer modelling of high-temperature failure in pipe weldments to optimize weld and heat affected zone materials property selection

    NASA Astrophysics Data System (ADS)

    Wang, Z. P.; Hayhurst, D. R.

    1994-07-01

    The creep deformation and damage evolution in a pipe weldment has been modeled by using the finite-element continuum damage mechanics (CDM) method. The finite-element CDM computer program DAMAGE XX has been adapted to run with increased speed on a Cray XMP/416 supercomputer. Run times are sufficiently short (20 min) to permit many parametric studies to be carried out on vessel lifetimes for different weld and heat affected zone (HAZ) materials. Finite-element mesh sensitivity was studied first in order to select a mesh capable of correctly predicting experimentally observed results using at least possible computer time. A study was then made of the effect on the lifetime of a butt welded vessel of each of the commomly measured material parameters for the weld and HAZ materials. Forty different ferritic steel welded vessels were analyzed for a constant internal pressure of 45.5 MPa at a temperature of 565 C; each vessel having the same parent pipe material but different weld and HAZ materials. A lifetime improvement has been demonstrated of 30% over that obtained for the initial materials property data. A methodology for weldment design has been established which uses supercomputer-based CDM analysis techniques; it is quick to use, provides accurate results, and is a viable design tool.

  12. Effect of welding conditions on transformation and properties of heat-affected zones in LWR (light-water reactor) vessel steels

    SciTech Connect

    Lundin, C.D.; Mohammed, S. . Welding Research and Engineering)

    1990-11-01

    The continuous cooling transformation behavior (CCT) and isothermal transformation (IT) behavior were determined for SA-508 and SA-533 materials for conditions pertaining to standard heat treatment and for the coarse-grained region of the heat-affected zone (HAZ). The resulting diagrams help to select welding conditions that produce the most favorable microconstituent for the development of optimum postweld heat treatment (PWHT) toughness levels. In the case of SA-508 and SA-533, martensite responds more favorably to PWHT than does bainite. Bainite is to be avoided for the optimum toughness characteristics of the HAZ. The reheat cracking tendency for both steels was evaluated by metallographic studies of simulated HAZ structures subjected to PWHT cycles and simultaneous restraint. Both SA-533, Grade B, Class 1, and SA-508, Class 2, cracked intergranularly. The stress rupture parameter (the product of the stress for a rupture life of 10 min and the corresponding reduction of area) calculated for both steels showed that SA-508, Class 2, was more susceptible to reheat cracking than SA-533, Grade B, Class 1. Cold cracking tests (Battelle Test and University of Tennessee modified hydrogen susceptibility test) indicated that a higher preheat temperature is required for SA-508, Class 2, to avoid cracking than is required for SA-533, Grade B, Class 1. Further, the Hydrogen Susceptibility Test showed that SA-508, Class 2, is more susceptible to hydrogen embrittlement than is SA-533, Grade B, Class 1.

  13. Laser cutting of graphite anodes for automotive lithium-ion secondary batteries: investigations in the edge geometry and heat-affected zone

    NASA Astrophysics Data System (ADS)

    Schmieder, Benjamin

    2012-03-01

    To serve the high need of lithium-ion secondary batteries of the automobile industry in the next ten years it is necessary to establish highly reliable, fast and non abrasive machining processes. In previous works [1] it was shown that high cutting speeds with several meters per second are achievable. For this, mainly high power single mode fibre lasers with up to several kilo watts were used. Since lithium-ion batteries are very fragile electro chemical systems, the cutting speed is not the only thing important. To guarantee a high cycling stability and a long calendrical life time the edge quality and the heat affected zone (HAZ) are equally important. Therefore, this paper tries to establish an analytical model for the geometry of the cutting edge based on the ablation thresholds of the different materials. It also deals with the composition of the HAZ in dependence of the pulse length, generated by laser remote cutting with pulsed fibre laser. The characterisation of the HAZ was done by optical microscopy, SEM, EDX and Raman microscopy.

  14. The influence of composition and microstructure on the HAZ toughness of duplex stainless steels at [minus]20 C

    SciTech Connect

    Lippold, J.C. ); Varol, I.; Baeslack, W.A. III )

    1994-04-01

    The toughness of two commercial duplex stainless steels, Ferralium Alloy 255 and Alloy 2205, was evaluated over a range of cooling rates representative of conditions in the weld heat-affected zone (HAZ). Both alloys exhibited a loss in toughness at the cooling rate extremes, 90 and 2 C/s, resulting from high ferrite content and larger prior ferrite grain size, respectively. Alloy 255 also showed a drop in toughness at an intermediate cooling rate of 50 C/s. This intermediate loss in toughness, not observed in Alloy 2205, results from the interrelationship between austenite and Cr-rich precipitate formation along ferrite grain boundaries. The precipitation mechanisms and their subsequent effect on toughness are described. The practical implications of HAZ microstructure control are also discussed.

  15. Evaluation of crack arrest fracture toughness of parent plate, weld metal and heat affected zone of BIS 812 EMA ship plate steel

    NASA Astrophysics Data System (ADS)

    Burch, I. A.

    1993-10-01

    The steel chosen for the pressure hull of the Collins class submarine has undergone evaluation to compare the crack arrest fracture toughness, K(Ia), of the parent plate with that of weld metal and heat affected zone. The tests were conducted over a range of subzero temperatures on specimens slightly outside the ASTM standard test method specimen configuration. Shallow face grooved specimens were used to vary the propagating crack velocity from that of non face grooved specimens and determine if K(Ia), is sensitive to changes in crack velocity. The weld metal, heat affected zone (HAZ), and parent plate were assessed to determine if the welding process had a deleterious effect on the crack arrest properties of this particular steel. Tests on each of these regions revealed that, for the combination of parent plate, welding procedure and consumables, no adverse effect on crack arrest properties was encountered. Crack arrest fracture toughness of the weld metal and HAZ was superior to that of the parent plate at comparable temperatures.

  16. Effect of long-term aging on microstructure and local behavior in the heat-affected zone of a Ni–Cr–Mo–V steel welded joint

    SciTech Connect

    Zhu, Ming-Liang Wang, De-Qiang; Xuan, Fu-Zhen

    2014-01-15

    Evolution of microstructure, micro-hardness and micro-tensile strength behavior was investigated in the heat-affected zone of a Ni–Cr–Mo–V steel welded joint after the artificial aging at 350 °C for 3000 h. After detailed characterization of microstructures in optical microscopy, scanning electron microscopy and transmission electron microscopy, it is revealed that the change of martensite–bainite constituent promotes more homogeneous microstructure distribution. The aging treatment facilitates redistribution of carbon and chromium elements along the welded joint, and the micro-hardness is increased slightly through the welds due to enrichment of carbon. The types of precipitates in the weldment mainly include M{sub 3}C, MC, M{sub 2}C and M{sub 23}C{sub 6}. The carbides in base metal, weld metal and coarse-grained heat-affected zone are prone to change from ellipsoidal to platelet form whereas more uniform spherical carbides are observed in the fine-grained zone. Precipitation and coarsening of M{sub 23}C{sub 6} near the fusion line, and formation of MC and M{sub 2}C, are responsible for the tensile strength decrease and its smooth distribution in the aged heat-affected zone. This implies that the thermal aging can relieve strength mismatch in the weldments. - Highlights: • Microstructure homogeneity improved in HAZ after long-term aging. • Tensile strength decreased in HAZ due to precipitation and coarsening of M{sub 23}C{sub 6}. • Strength mismatch in NiCrMoV steel welds was relieved after aging at 350 °C × 3000 h.

  17. In-Situ Observations of Phase Transformations in the HAZ of 2205 Duplex Stainless Steel Weldments

    SciTech Connect

    Palmer, T A; Elmer, J W; Wong, J

    2001-08-15

    Ferrite ({delta})/austenite ({gamma}) transformations in the heat affected zone (HAZ) of a gas tungsten arc (GTA) weld in 2205 duplex stainless steel are observed in real-time using spatially resolved X-ray diffraction (SRXRD) with high intensity synchrotron radiation. A map showing the locations of the {delta} and {gamma} phases with respect to the calculated weld pool dimensions has been constructed from a series of SRXRD scans. Regions of liquid, completely transformed {gamma}, a combination of partially transformed {gamma} with untransformed {delta}, and untransformed {delta}+{gamma} are identified. Analysis of each SRXRD pattern provides a semi-quantitative definition of both the {delta}/{gamma} phase balance and the extent of annealing which are mapped for the first time with respect to the calculated weld pool size and shape. A combination of these analyses provides a unique real-time description of the progression of phase transformations in the HAZ. Using these real-time observations, important kinetic information about the transformations occurring in duplex stainless steels during heating and cooling cycles typical of welding can be determined.

  18. Effects of alloying elements on fracture toughness in the transition temperature region of base metals and simulated heat-affected zones of Mn-Mo-Ni low-alloy steels

    NASA Astrophysics Data System (ADS)

    Kim, Sangho; Im, Young-Roc; Lee, Sunghak; Lee, Hu-Chul; Kim, Sung-Joon; Hong, Jun Hwa

    2004-07-01

    This study is concerned with the effects of alloying elements on fracture toughness in the transition temperature region of base metals and heat-affected zones (HAZs) of Mn-Mo-Ni low-alloy steels. Three kinds of steels whose compositions were varied from the composition specification of SA 508 steel (grade 3) were fabricated by vacuum-induction melting and heat treatment, and their fracture toughness was examined using an ASTM E1921 standard test method. In the steels that have decreased C and increased Mo and Ni content, the number of fine M2C carbides was greatly increased and the number of coarse M3C carbides was decreased, thereby leading to the simultaneous improvement of tensile properties and fracture toughness. Brittle martensite-austenite (M-A) constituents were also formed in these steels during cooling, but did not deteriorate fracture toughness because they were decomposed to ferrite and fine carbides after tempering. Their simulated HAZs also had sufficient impact toughness after postweld heat treatment. These findings indicated that the reduction in C content to inhibit the formation of coarse cementite and to improve toughness and the increase in Mo and Ni to prevent the reduction in hardenability and to precipitate fine M2C carbides were useful ways to improve simultaneously the tensile and fracture properties of the HAZs as well as the base metals.

  19. Root-Zone Glyphosate Exposure Adversely Affects Two Ditch Species

    PubMed Central

    Saunders, Lyndsay E.; Koontz, Melissa B.; Pezeshki, Reza

    2013-01-01

    Glyphosate, one of the most applied herbicides globally, has been extensively studied for its effects on non-target organisms. In the field, following precipitation, glyphosate runs off into agricultural ditches where it infiltrates into the soil and thus may encounter the roots of vegetation. These edge-of-field ditches share many characteristics with wetlands, including the ability to reduce loads of anthropogenic chemicals through uptake, transformation, and retention. Different species within the ditches may have a differential sensitivity to exposure of the root zone to glyphosate, contributing to patterns of abundance of ruderal species. The present laboratory experiment investigated whether two species commonly found in agricultural ditches in southcentral United States were affected by root zone glyphosate in a dose-dependent manner, with the objective of identifying a sublethal concentration threshold. The root zone of individuals of Polygonum hydropiperoides and Panicum hemitomon were exposed to four concentrations of glyphosate. Leaf chlorophyll content was measured, and the ratio of aboveground biomass to belowground biomass and survival were quantified. The findings from this study showed that root zone glyphosate exposure negatively affected both species including dose-dependent reductions in chlorophyll content. P. hydropiperdoides showed the greatest negative response, with decreased belowground biomass allocation and total mortality at the highest concentrations tested. PMID:24833234

  20. A process model for the heat-affected zone microstructure evolution in duplex stainless steel weldments: Part II. Application to electron beam welding

    NASA Astrophysics Data System (ADS)

    Hemmer, H.; Grong, Ø.; Klokkehaug, S.

    2000-03-01

    In the present investigation, a process model for electron beam (EB) welding of different grades of duplex stainless steels (i.e. SAF 2205 and 2507) has been developed. A number of attractive features are built into the original finite element code, including (1) a separate module for prediction of the penetration depth and distribution of the heat source into the plate, (2) adaptive refinement of the three-dimensional (3-D) element mesh for quick and reliable solution of the differential heat flow equation, and (3) special subroutines for calculation of the heat-affected zone (HAZ) microstructure evolution. The process model has been validated by comparison with experimental data obtained from in situ thermocouple measurements and optical microscope examinations. Subsequently, its aptness to alloy design and optimization of welding conditions for duplex stainless steels is illustrated in different numerical examples and case studies pertaining to EB welding of tubular joints.

  1. Hazardous chemical tracking system (HAZ-TRAC)

    SciTech Connect

    Bramlette, J D; Ewart, S M; Jones, C E

    1990-07-01

    Westinghouse Idaho Nuclear Company, Inc. (WINCO) developed and implemented a computerized hazardous chemical tracking system, referred to as Haz-Trac, for use at the Idaho Chemical Processing Plant (ICPP). Haz-Trac is designed to provide a means to improve the accuracy and reliability of chemical information, which enhances the overall quality and safety of ICPP operations. The system tracks all chemicals and chemical components from the time they enter the ICPP until the chemical changes form, is used, or becomes a waste. The system runs on a Hewlett-Packard (HP) 3000 Series 70 computer. The system is written in COBOL and uses VIEW/3000, TurboIMAGE/DBMS 3000, OMNIDEX, and SPEEDWARE. The HP 3000 may be accessed throughout the ICPP, and from remote locations, using data communication lines. Haz-Trac went into production in October, 1989. Currently, over 1910 chemicals and chemical components are tracked on the system. More than 2500 personnel hours were saved during the first six months of operation. Cost savings have been realized by reducing the time needed to collect and compile reporting information, identifying and disposing of unneeded chemicals, and eliminating duplicate inventories. Haz-Trac maintains information required by the Superfund Amendment Reauthorization Act (SARA), the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) and the Occupational Safety and Health Administration (OSHA).

  2. Characterization of Low Temperature Ferrite/Austenite Transformations in the Heat Affected Zone of 2205 Duplex Stainless Steel Arc Welds

    SciTech Connect

    Palmer, T A; Elmer, J W; Babu, S S; Vitek, J M

    2003-08-20

    Spatially Resolved X-Ray Diffraction (SRXRD) has been used to identify a previously unobserved low temperature ferrite ({delta})/austenite({gamma}) phase transformation in the heat affected zone (HAZ) of 2205 Duplex Stainless Steel (DSS) welds. In this ''ferrite dip'' transformation, the ferrite transforms to austenite during heating to peak temperatures on the order of 750 C, and re-transforms to ferrite during cooling, resulting in a ferrite volume fraction equivalent to that in the base metal. Time Resolved X-Ray Diffraction (TRXRD) and laser dilatometry measurements during Gleeble{reg_sign} thermal simulations are performed in order to verify the existence of this low temperature phase transformation. Thermodynamic and kinetic models for phase transformations, including both local-equilibrium and para-equilibrium diffusion controlled growth, show that diffusion of substitutional alloying elements does not provide a reasonable explanation for the experimental observations. On the other hand, the diffusion of interstitial alloying elements may be rapid enough to explain this behavior. Based on both the experimental and modeling results, two mechanisms for the ''ferrite dip'' transformation, including the formation and decomposition of secondary austenite and an athermal martensitic-type transformation of ferrite to austenite, are considered.

  3. 49 CFR 222.42 - How does this rule affect Intermediate Quiet Zones and Intermediate Partial Quiet Zones?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... LOCOMOTIVE HORNS AT PUBLIC HIGHWAY-RAIL GRADE CROSSINGS Exceptions to the Use of the Locomotive Horn Silenced Horns at Groups of Crossings-Quiet Zones § 222.42 How does this rule affect Intermediate Quiet Zones...

  4. 49 CFR 222.42 - How does this rule affect Intermediate Quiet Zones and Intermediate Partial Quiet Zones?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... LOCOMOTIVE HORNS AT PUBLIC HIGHWAY-RAIL GRADE CROSSINGS Exceptions to the Use of the Locomotive Horn Silenced Horns at Groups of Crossings-Quiet Zones § 222.42 How does this rule affect Intermediate Quiet Zones...

  5. 49 CFR 222.42 - How does this rule affect Intermediate Quiet Zones and Intermediate Partial Quiet Zones?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... LOCOMOTIVE HORNS AT PUBLIC HIGHWAY-RAIL GRADE CROSSINGS Exceptions to the Use of the Locomotive Horn Silenced Horns at Groups of Crossings-Quiet Zones § 222.42 How does this rule affect Intermediate Quiet Zones...

  6. 49 CFR 222.42 - How does this rule affect Intermediate Quiet Zones and Intermediate Partial Quiet Zones?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... LOCOMOTIVE HORNS AT PUBLIC HIGHWAY-RAIL GRADE CROSSINGS Exceptions to the Use of the Locomotive Horn Silenced Horns at Groups of Crossings-Quiet Zones § 222.42 How does this rule affect Intermediate Quiet Zones...

  7. 49 CFR 222.42 - How does this rule affect Intermediate Quiet Zones and Intermediate Partial Quiet Zones?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... LOCOMOTIVE HORNS AT PUBLIC HIGHWAY-RAIL GRADE CROSSINGS Exceptions to the Use of the Locomotive Horn Silenced Horns at Groups of Crossings-Quiet Zones § 222.42 How does this rule affect Intermediate Quiet Zones...

  8. An investigation of reheat cracking in the weld heat affected zone of type 347 stainless steel

    NASA Astrophysics Data System (ADS)

    Phung-On, Isaratat

    2007-12-01

    microvoid corresponds to the size of precipitate that forms. In addition, there was intragranular cracking in some location indicating that another failure mechanism may also be possible. It was believed that failure may occur along a precipitate free zone. However, the distinct PFZ could not be detected. A SS-DTA technique was also implemented in order to determine precipitation temperatures of the material. The results showed the possible precipitation temperatures in the range of 850°C to 650°C. However, the results were not confidently reliable due to the small amount of carbide formed that affects the sensitivity of the SS-DTA. A simple grain boundary sliding model was generated proposing that the sliding is operated by the shear stress resulting from the formation of precipitate in the grain interior. Then, the sliding results in the microvoid formation and coalescence followed by cracking. In addition, a simple finite element model was generated to provide the illustration of the shear stress built up by the formation of precipitate. The model showed that shear stress can cause the grain boundary movement/sliding. Based on the results from this study, the recommendation for the selection of post weld heat treatment schedule as well as welding procedures can be determined for the prevention of the reheat cracking. A residual stress should be kept below the critical value during welding and post weld heat treating. The testing procedures used in this study can be applied as the guidelines to conduct the reheat cracking susceptibility test for material selection.

  9. Evaluation of HAZ liquation cracking susceptibility and HAZ softening behavior in modified 800H

    SciTech Connect

    Lundin, C.D.; Qiao, C.Y.P.

    1992-11-20

    A modified 800H alloy, developed at Oak Ridge National Laboratory (ORNL), is one of the candidate materials designed for high temperature applications. Extensive mechanical and corrosion investigations have been completed and it has been proven that modified 800 has excellent high temperature mechanical and metallurgical behavior. Weldability studies of modified 800H are being carried out at the University of Tennessee, Knoxville. A series of modified 800H alloys and two similar commercial high temperature materials (310Ta and HR3C) were used to conduct this investigation. A preliminary weldability evaluation has been accomplished and the major part of the results (HAZ liquation cracking resistance and HAZ softening behavior in modified 800H) is addressed in this report. The basic conclusion of this investigation is that modified 800H material possesses good resistance to HAZ liquation cracking especially with a grain size control (thermo-mechanical treatment). The information from this study is important to the further modification of the material in order to extend its applications.

  10. Observations of Ferrite/Austenite Transformations in the Heat Affected Zone of 2205 Duplex Stainless Steel Spot Welds Using Time Resolved X-Ray Diffraction

    SciTech Connect

    Palmer, T; Elmer, J; Babu, S

    2003-10-29

    Time Resolved X-Ray Diffraction (TRXRD) measurements are made in the Heat Affected Zone (HAZ) of 2205 Duplex Stainless Steel (DSS) spot welds. Both the {gamma} {yields} {delta} and {delta} {yields} {gamma} transformations are monitored as a function of time during the rapid spot weld heating and cooling cycles. These observations are then correlated with calculated thermal cycles. Where the peak temperatures are highest ({approx}1342 C), the {gamma} {yields} {delta} transformation proceeds to completion, leaving a ferritic microstructure at the end of heating. With lower peak temperatures, the {gamma} {yields} {delta} transformation proceeds to only partial completion, resulting in a microstructure containing both transformed and untransformed austenite. Further analyses of the individual diffraction patterns show shifts in the peak positions and peak widths as a function of both time and temperature. In addition, these changes in the peak characteristics are correlated with measured changes in the ferrite volume fraction. Such changes in the peak positions and widths during the {gamma} {yields} {delta} transformation provide an indication of changes occurring in each phase. These changes in peak properties can be correlated with the diffusion of nitrogen and other substitutional alloying elements, which are recognized as the primary mechanisms for this transformation. Upon cooling, the {delta} {yields} {gamma} transformation is observed to proceed from both the completely and partially transformed microstructural regions in the TRXRD data. An examination of the resulting microstructures confirms the TRXRD observation as the evidence shows that austenite both nucleates and grows from the ferritic microstructure at locations closest to the fusion zone boundary and grows from untransformed austenite grains at locations further from this boundary.

  11. Haz-Safe material handling in hazmat buildings

    SciTech Connect

    Romig, F.W.

    1994-12-31

    Material handling techniques have begun to be utilized in hazmat buildings for maneuvering and stacking of hazardous material containers. Therefore, the efficiencies involved in increased safety and productivity are being realized. In addition, there are savings in HazMat building costs and floor space or real estate inside or outside manufacturing plants. Stacking of containers is being used as structures are beefed up to install crane/hoists or air power mast type stacking machines. The purpose of this paper is to encourage potential HazMat building users and the material handling industry to look for opportunities to project material handling technology into hazmat buildings.

  12. Effect of Heat Treatment on Microstructure and Hot Impact Toughness of Various Zones of P91 Welded Pipes

    NASA Astrophysics Data System (ADS)

    Pandey, C.; Mahapatra, M. M.

    2016-06-01

    The new generation super critical thermal power plants are required to operate at enhanced thermal efficiency of over 50% to reduce the fuel consumption and environmental pollution. Creep strength-enhanced ferritic steels, commonly known as Cr-Mo alloys such as P91 (X10CrMoVNb 9-1) are such material of choice for the next generation power plants. The operating requirement of these next generation power plants is that steam temperature of around 650 °C is maintained. For such high-temperature application, creep strength of material is the primary consideration together with adequate weld heat-affected zone (HAZ) toughness. Present work deals with the effect of high service temperature on impact toughness of P91 (X10CrMoVNb 9-1) base material, weld fusion zone, and HAZ. The impact toughness of HAZ for conventional weld groove design and narrow weld groove design has been evaluated experimentally in as-welded and at different post-weld heat treatment conditions. Fractography of the impact toughness specimens of base metal, weld fusion zone, and HAZ was carried out using scanning electron microscope. The effects of heat treatment schemes on the percentage of element present at the fracture surface were also studied.

  13. 49 CFR 222.41 - How does this rule affect Pre-Rule Quiet Zones and Pre-Rule Partial Quiet Zones?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... AT PUBLIC HIGHWAY-RAIL GRADE CROSSINGS Exceptions to the Use of the Locomotive Horn Silenced Horns at Groups of Crossings-Quiet Zones § 222.41 How does this rule affect Pre-Rule Quiet Zones and Pre-Rule... public highway-rail grade crossing within the quiet zone one or more SSMs identified in appendix A...

  14. 49 CFR 222.41 - How does this rule affect Pre-Rule Quiet Zones and Pre-Rule Partial Quiet Zones?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... AT PUBLIC HIGHWAY-RAIL GRADE CROSSINGS Exceptions to the Use of the Locomotive Horn Silenced Horns at Groups of Crossings-Quiet Zones § 222.41 How does this rule affect Pre-Rule Quiet Zones and Pre-Rule... public highway-rail grade crossing within the quiet zone one or more SSMs identified in appendix A...

  15. 49 CFR 222.41 - How does this rule affect Pre-Rule Quiet Zones and Pre-Rule Partial Quiet Zones?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... AT PUBLIC HIGHWAY-RAIL GRADE CROSSINGS Exceptions to the Use of the Locomotive Horn Silenced Horns at Groups of Crossings-Quiet Zones § 222.41 How does this rule affect Pre-Rule Quiet Zones and Pre-Rule... public highway-rail grade crossing within the quiet zone one or more SSMs identified in appendix A...

  16. 49 CFR 222.41 - How does this rule affect Pre-Rule Quiet Zones and Pre-Rule Partial Quiet Zones?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... AT PUBLIC HIGHWAY-RAIL GRADE CROSSINGS Exceptions to the Use of the Locomotive Horn Silenced Horns at Groups of Crossings-Quiet Zones § 222.41 How does this rule affect Pre-Rule Quiet Zones and Pre-Rule... public highway-rail grade crossing within the quiet zone one or more SSMs identified in appendix A...

  17. 49 CFR 222.41 - How does this rule affect Pre-Rule Quiet Zones and Pre-Rule Partial Quiet Zones?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... AT PUBLIC HIGHWAY-RAIL GRADE CROSSINGS Exceptions to the Use of the Locomotive Horn Silenced Horns at Groups of Crossings-Quiet Zones § 222.41 How does this rule affect Pre-Rule Quiet Zones and Pre-Rule... public highway-rail grade crossing within the quiet zone one or more SSMs identified in appendix A...

  18. HAZ-ED Classroom Activities for Understanding Hazardous Waste.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

    The Federal Superfund Program investigates and cleans up hazardous waste sites throughout the United States. Part of this program is devoted to informing the public and involving people in the process of cleaning up hazardous waste sites from beginning to end. The Haz-Ed program was developed to assist the Environmental Protection Agency's (EPA)…

  19. 30 CFR 47.32 - HazCom program contents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false HazCom program contents. 47.32 Section 47.32 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD... must— (1) Use a chemical identity that permits cross-referencing between the list, a chemical's...

  20. Identification and Characterization of Intercritical Heat-Affected Zone in As-Welded Grade 91 Weldment

    NASA Astrophysics Data System (ADS)

    Wang, Yiyu; Kannan, Rangasayee; Li, Leijun

    2016-09-01

    A metallurgical method is proposed for locating the intercritical heat-affected zone in the as-welded Grade 91 steel. New austenitic grains, preferentially formed along the original prior austenite grain boundaries, are characterized to contain finer M23C6 carbides and higher strain levels than the original prior austenite grains. Kurdjumov-Sachs Group 1 variant pairs, with a low misorientation of 7 deg within a martensitic block, are identified as the dominant variants in the new PAGs.

  1. Characterizing multiple timescales of stream and storage zone interaction that affect solute fate and transport in streams

    USGS Publications Warehouse

    Choi, J.; Harvey, J.W.; Conklin, M.H.

    2000-01-01

    The fate of contaminants in streams and rivers is affected by exchange and biogeochemical transformation in slowly moving or stagnant flow zones that interact with rapid flow in the main channel. In a typical stream, there are multiple types of slowly moving flow zones in which exchange and transformation occur, such as stagnant or recirculating surface water as well as subsurface hyporheic zones. However, most investigators use transport models with just a single storage zone in their modeling studies, which assumes that the effects of multiple storage zones can be lumped together. Our study addressed the following question: Can a single-storage zone model reliably characterize the effects of physical retention and biogeochemical reactions in multiple storage zones? We extended an existing stream transport model with a single storage zone to include a second storage zone. With the extended model we generated 500 data sets representing transport of nonreactive and reactive solutes in stream systems that have two different types of storage zones with variable hydrologic conditions. The one storage zone model was tested by optimizing the lumped storage parameters to achieve a best fit for each of the generated data sets. Multiple storage processes were categorized as possessing I, additive; II, competitive; or III, dominant storage zone characteristics. The classification was based on the goodness of fit of generated data sets, the degree of similarity in mean retention time of the two storage zones, and the relative distributions of exchange flux and storage capacity between the two storage zones. For most cases (> 90%) the one storage zone model described either the effect of the sum of multiple storage processes (category I) or the dominant storage process (category III). Failure of the one storage zone model occurred mainly for category II, that is, when one of the storage zones had a much longer mean retention time (t(s) ratio > 5.0) and when the dominance of

  2. Performance processes within affect-related performance zones: a multi-modal investigation of golf performance.

    PubMed

    van der Lei, Harry; Tenenbaum, Gershon

    2012-12-01

    Individual affect-related performance zones (IAPZs) method utilizing Kamata et al. (J Sport Exerc Psychol 24:189-208, 2002) probabilistic model of determining the individual zone of optimal functioning was utilized as idiosyncratic affective patterns during golf performance. To do so, three male golfers of a varsity golf team were observed during three rounds of golf competition. The investigation implemented a multi-modal assessment approach in which the probabilistic relationship between affective states and both, performance process and performance outcome, measures were determined. More specifically, introspective (i.e., verbal reports) and objective (heart rate and respiration rate) measures of arousal were incorporated to examine the relationships between arousal states and both, process components (i.e., routine consistency, timing), and outcome scores related to golf performance. Results revealed distinguishable and idiosyncratic IAPZs associated with physiological and introspective measures for each golfer. The associations between the IAPZs and decision-making or swing/stroke execution were strong and unique for each golfer. Results are elaborated using cognitive and affect-related concepts, and applications for practitioners are provided.

  3. The problems of weld metal or heat affected zone toughness in offshore structural steels

    SciTech Connect

    Hancock, P.; Spurrier, J.; Chubb, J.P.

    1996-12-01

    An extensive set of fracture toughness results for welded offshore structural steels, gathered from nine separate sponsoring companies, has been entered into a specially constructed database. With over eleven thousand Charpy results and over two thousand CTOD results available, it has been possible to analyze the occurrence of low toughness results with respect to variables such as thickness, PWHT, steel production route etc., even though the individual test programs were not specifically structured to do this. This paper concentrates on the toughness of the weld metal. The data demonstrates that the likelihood of a low toughness result from a CTOD test in weld metal at {minus}10 C is comparable with that from the HAZ region for welded offshore structural steels, and PWHT of the joint is beneficial in reducing the occurrence of low toughness values in the weld metal. It is therefore important that when the HAZ performance is assessed, either through weld procedure tests or plate prequalification procedures, adequate attention is also paid to the weld metal toughness.

  4. The effect of welding line heat-affected-zone on the formability of tube hydroforming process

    NASA Astrophysics Data System (ADS)

    ChiuHuang, Cheng-Kai; Hsu, Cheng-En; Lee, Ping-Kun

    2016-08-01

    Tube hydroforming has been used as a lightweight design approach to reduce CO2 emission for the automotive industry. For the high strength steel tube, the strength and quality of the welding line is very important for a successful tube hydroforming process. This paper aims to investigate the effect of the welding line's strength and the width of the heat-affected zone on the tube thinning during the hydroforming process. The simulation results show that both factors play an important role on the thickness distribution during the tube expansion.

  5. Microstructure characterization of heat affected zone after welding in Mod.9Cr–1Mo steel

    SciTech Connect

    Sawada, K.; Hara, T.; Tabuchi, M.; Kimura, K.; Kubushiro, K.

    2015-03-15

    The microstructure of the heat affected zone after welding was investigated in Mod.9Cr–1Mo steel, using TEM and STEM-EDX. The microstructure of thin foil was observed at the fusion line, and at the positions of 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm and 3.5 mm to the base metal side of the fusion line. Martensite structure with very fine lath and high dislocation density was confirmed at all positions. Twins with a twin plane of (112) were locally observed at all positions. Elemental mapping was obtained for all positions by means of STEM-EDX. Inclusions of mainly Si were formed at the fusion line but not at the other positions. No precipitates could be detected at the fusion line or at the position of 0.5 mm. On the other hand, MX particles were observed at the positions of 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm and 3.5 mm even after welding. M{sub 23}C{sub 6} particles were also confirmed at the positions of 2.0 mm, 2.5 mm, 3.0 mm and 3.5 mm. Very fine equiaxed grains were locally observed at the positions of 2.0 mm and 2.5 mm. The Cr content of the equiaxed grains was about 12 mass%, although the martensite area included about 8 mass% Cr. - Graphical abstract: Display Omitted - Highlights: • Nonequilibrium microstructure of heat affected zone was observed after welding in Mod.9Cr–1Mo steel. • Inclusions containing Si were detected at the fusion line. • Undissolved M{sub 23}C{sub 6} and MX particles were confirmed in heat affected zone. • Twins with a twin plane of (112) were locally observed at all positions. • Very fine ferrite grains with high Cr content were observed in fine grained heat affected zone.

  6. Irradiation effects on weld heat-affected zone and plate materials (series 11)

    SciTech Connect

    Nanstad, R.K.; McCabe, D.E.

    1995-10-01

    The purpose of this task is to examine the effects of neutron irradiation on the fracture toughness (ductile and brittle) of the HAZ of welds and of A 302 grade B (A302B) plate materials typical of those used fabricating older RPVs. The initial plate material of emphasis will be A302B steel, not the A302B modified with nickel additions. This decision was made by the NRC following a survey of the materials of construction for RPBs in operating U.S. nuclear plants. Reference 1 was used for the preliminary survey, and the information from that report was revised by NRC staff based on information contained in the licensee responses to Generic Letter (GL) 92-01, {open_quotes}Reactor Vessel Structural Integrity, 10CFR50.54(f).{close_quotes} The resulting survey showed a total of eight RPVs with A302B, ten with A302B (modified), and one with A302 grade A plate. Table 5.1 in the previous semiannual report provides a summary of that survey. For the HAZ portion of the program, the intent is to examine HAZ material in the A302B (i.e., with low nickel content) and in A302B (modified) or A533B-1 (i.e., with medium nickel content). During this reporting period, two specific plates were identified as being applicable to this task. One plate is A302B and the other is A302B (modified). The A302B plate (43 x 42 x 7 in.) will be prepared for welding, while the A302B (modified) plate already contains a commercially produced weld (heat 33A277, Linde 0091 flux). These plates were identified from a list of ten materials provided by Mr. E. Biemiller of Yankee Atomic Electric Company (YAEC). The materials have been requested from YAEC for use in this irradiation task, and arrangements are being made with YAEC for procurement of the plates mentioned above.

  7. Factors affecting the kinematic interpretation of asymmetric boudinage in shear zones

    NASA Astrophysics Data System (ADS)

    Goldstein, Arthur G.

    Based on work along a major mylonite zone in the northern Appalachians and scale model studies, a new mechanism for the origin of asymmetric boudins in shear zones is proposed. Along the Honey Hill Fault in southern Connecticut, granitic sills intruded into calc-silicate gneisses and schists were oblique to the boundaries of the mylonite zone and experienced the following sequence in the production of sigmoidal boudins: (1) as the calc-silicate schists experienced mylonitization and flow, the more competent, coarse-grained granitic sills deformed by extensional fracturing and quartz veining; (2) continued extension of granitic sills was accommodated by 'normal' shear on early-formed quartz veins; (3) continuing extension of sills and ductile modification of the corners of boudins resulted in granitic 'fish' with tails which stream from the top of the boudin in the 'down-dip' direction and from the bottom in the 'up-dip' direction. Based on a variety of kinematic indicators, the sense of asymmetry of the tails is identical to that expected for recrystallization tails on sheared augen (σ structure). Models composed of silicone putty and Plasticine were created to investigate the effect of pre-shearing geometry on boudin evolution, and were deformed in a simple shear device. The models reproduce the kinematics deduced from field relations and suggest that one of the primary factors in controlling the amount of extension is the angle which early veins make with the shear zone boundary. Varying the angular relationships in the models suggests that other pre-shearing geometric factors may affect the geometry of boudins formed in this way. Boudins formed through this mechanism appear very similar to Hanmer's type II asymmetric boudins. Because the pre-shearing geometry can exert a control on boudin asymmetry, caution should be used when attempting to deduce shear sense or shear strain values from asymmetric boudinage.

  8. 30 CFR 47.31 - Requirement for a HazCom program.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Requirement for a HazCom program. 47.31 Section 47.31 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND... hazardous chemical is known to be at the mine, and (c) Share relevant HazCom information with other...

  9. Bioenhanced DNAPL Dissolution: Understanding how Microbial Competition, Biostimulation, and Bioaugmentation Affect Source Zone Longevity

    NASA Astrophysics Data System (ADS)

    Becker, J. G.; Seagren, E. A.

    2006-12-01

    The presence of dense non-aqueous phase liquids (DNAPLs) at many chlorinated ethene-contaminated sites can greatly extend the time frames needed to reduce dissolved contaminants to regulatory levels using bioremediation. However, it has been demonstrated that mass removal from chlorinated ethene DNAPLs can potentially be enhanced through dehalorespiration of dissolved contaminants near the NAPL-water interface. Although promising, the amount of "bioenhancement" that can be achieved under optimal conditions is currently not known, and the real significance and engineering potential of this phenomenon currently are not well understood, in part because it can be influenced by a complex set of factors, including DNAPL properties, hydrodynamics, substrate concentrations, and microbial competition for growth substrates. In this study it is hypothesized that: (1) different chlorinated ethene-respiring strains may dominate within different zones of a contaminant plume emanating from a DNAPL source zone due to variations in substrate availability, and microbial competition for chlorinated ethenes and/or electron donors; and (2) the outcome of competitive interactions near the DNAPL source zone will affect the longevity of DNAPL source zones by influencing the degree of dissolution bioenhancement, while the outcome of competitive interactions further downgradient will determine the extent of contaminant dechlorination. To demonstrate the validity of the proposed hypothesis, a series of simple, "proof-of-concept," mathematical simulations evaluating the effects of competitive interactions on the distribution of dehalorespirers at the DNAPL-water interface, the dissolution of tetrachloroethene (PCE), and extent of PCE detoxification were performed in a model competition scenario, in which Dehalococcoides ethenogenes and another dehalorespirer (Desulfuromonas michiganensis) compete for the electron acceptor (PCE) and/or electron donor. The model domain for this evaluation

  10. Spatial changes of Extended De Martonne climatic zones affected by climate change in Iran

    NASA Astrophysics Data System (ADS)

    Rahimi, Jaber; Ebrahimpour, Meisam; Khalili, Ali

    2013-05-01

    In order to better understand the effect associated with global climate change on Iran's climate condition, it is important to quantify possible shifts in different climatic types in the future. To this end, monthly mean minimum and maximum temperature, and precipitation from 181 synoptic meteorological stations (average 1970-2005) have been collected from the meteorological organization of Iran. In this paper, to study spatial changes of Iran's climatic zones affected by climate changes, Extended De Martonne's classification (originally formulated by De Martonne and extended by Khalili (1992)) was used. Climate change scenarios were simulated in two future climates (average conditions during the 2050s and the 2080s) under each of the SRES A1B and A2, for the CSIRO-MK3, HadCM3, and CGCM3 climate models. Coarse outputs of GCMs were downscaled by delta method. We produced all maps for three time periods (one for the current and two for the future) according to Extended De Martonne's classification. Finally, for each climatic zone, changes between the current and the future were compared. As the main result, simulated changes indicate shifts to warmer and drier zones. For example, in the current, extra arid-cold ( A1.1m2) climate is covering the largest area of the country (21.4 %), whereas in both A1B and A2 scenarios in the 2050s and the 2080s, extra arid-moderate ( A1.1m3) and extra arid-warm ( A1.1m4) will be the climate and will occupy the largest area of the country, about 21 and 38 %, respectively. This analysis suggests that the global climate change will have a profound effect on the future distribution of severe aridity in Iran.

  11. Zones of impact around icebreakers affecting beluga whales in the Beaufort Sea.

    PubMed

    Erbe, C; Farmer, D M

    2000-09-01

    A software model estimating zones of impact on marine mammals around man-made noise [C. Erbe and D. M. Farmer, J. Acoust. Soc. Am. 108, 1327-1331 (2000)] is applied to the case of icebreakers affecting beluga whales in the Beaufort Sea. Two types of noise emitted by the Canadian Coast Guard icebreaker Henry Larsen are analyzed: bubbler system noise and propeller cavitation noise. Effects on beluga whales are modeled both in a deep-water environment and a near-shore environment. The model estimates that the Henry Larsen is audible to beluga whales over ranges of 35-78 km, depending on location. The zone of behavioral disturbance is only slightly smaller. Masking of beluga communication signals is predicted within 14-71-km range. Temporary hearing damage can occur if a beluga stays within 1-4 km of the Henry Larsen for at least 20 min. Bubbler noise impacts over the short ranges quoted; propeller cavitation noise accounts for all the long-range effects. Serious problems can arise in heavily industrialized areas where animals are exposed to ongoing noise and where anthropogenic noise from a variety of sources adds up.

  12. The role of fault zones in affecting multiphase flow at Yucca Mountain

    SciTech Connect

    Tsang, Y.W.; Pruess, K.; Wang, J.S.Y.

    1993-01-01

    Within Yucca Mountain, the potential High Level Nuclear-Waste Repository site, there are large scale fault zones, most notably the Ghost Dance Fault. The effect of such high-permeability, large scale discontinuities on the flow and transport is a question of concern in assessing the ability of the site to isolate radio-nuclides from the biosphere. In this paper, we present a numerical study to investigate the role of the fault in affecting both the liquid and gas phase flows in the natural state at Yucca Mountain prior to waste emplacement, as well as after the waste emplacement when the fluid flow is strongly heat-driven. Our study shows that if the characteristic curves of the Ghost Dance Fault obey the same relationship between saturated permeability and capillary scaling parameter, as is observed from the measured data of Yucca Mountain welded and nonwelded tuffs. Apache Leap tuffs, and Las Cruces soil, then a large saturated permeability of the Ghost Dance Fault will play little role in channeling water into the fault, or inenhancing the flow of water down the fault. However, the Fault may greatly enhance the upward gas flow after emplacement of waste. This may have implications on the transport of gaseous radio-nuclides such as C{sup 14}. The results of this study also focus attention on the need for field measurements of fluid flow in the fault zones.

  13. Plant hybrid zones affect biodiversity: Tools for a genetic-based understanding of community structure

    SciTech Connect

    Whitham, T.G.; Martinsen, G.D.; Keim, P.; Floate, K.D.; Dungey, H.S. |; Potts, B.M.

    1999-03-01

    Plant hybrid zones are dynamic centers of ecological and evolutionary processes for plants and their associated communities. Studies in the wild and in gardens with synthetic crosses showed that hybrid eucalypts supports the greatest species richness and abundances of insect and fungal taxa. In an updated review of 152 case studies of taxa associated with diverse hybridizing systems, there were 43 (28%) cases of hybrids being more susceptible than their parent species, 7 (5%) resistant, 35 (23%) additive, 35 (23%) dominant, and 32 (21%) showed no response to hybridization. Thus, most taxa respond to hybrids in ways that result in equal or greater abundance, and hybrids tend to accumulate the taxa of their parent species. These studies suggest that genetic-based plant traits affect the distribution of many species and that the variation in hybrids can be used as tools to examine the genetic components of community structure and biodiversity.

  14. Root-zone acidity affects relative uptake of nitrate and ammonium from mixed nitrogen sources

    NASA Technical Reports Server (NTRS)

    Vessey, J. K.; Henry, L. T.; Chaillou, S.; Raper, C. D. Jr; Raper CD, J. r. (Principal Investigator)

    1990-01-01

    Soybean plants (Glycine max [L.] Merr. cv Ransom) were grown for 21 days on 4 sources of N (1.0 mM NO3-, 0.67 mM NO3- plus 0.33 mM NH4+, 0.33 mM NO3- plus 0.67 mM NH4+, and 1.0 mM NH4+) in hydroponic culture with the acidity of the nutrient solution controlled at pH 6.0, 5.5, 5.0, and 4.5. Dry matter and total N accumulation of the plants was not significantly affected by N-source at any of the pH levels except for decreases in these parameters in plants supplied solely with NH4+ at pH 4.5. Shoot-to-root ratios increased in plants which had an increased proportion [correction of proporiton] of NH4(+)-N in their nutrient solutions at all levels of root-zone pH. Uptake of NO3- and NH4+ was monitored daily by ion chromatography as depletion of these ions from the replenished hydroponic solutions. At all pH levels the proportion of either ion that was absorbed increased as the ratio of that ion increased in the nutrient solution. In plants which were supplied with sources of NO3- plus NH4+, NH4+ was absorbed at a ratio of 2:1 over NO3- at pH 6.0. As the pH of the root-zone declined, however, NH4+ uptake decreased and NO3- uptake increased. Thus, the NH4+ to NO3- uptake ratio declined with decreases in root-zone pH. The data indicate a negative effect of declining root-zone pH on NH4+ uptake and supports a hypothesis that the inhibition of growth of plants dependent on NH4(+)-N at low pH is due to a decline in NH4+ uptake and a consequential limitation of growth by N stress.

  15. Flavor of oranges as impacted by abscission zone formation for trees affected by huanglongbing disease and Lasiodiploida infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trees affected by Huanglongbing (HLB) exhibit excessive fruit drop, which is exacerbated by secondary infection of the abscission zone by the fungus Lasiodiplodia. ‘Hamlin’ orange trees, both healthy and affected by HLB, Candidatus Liberibacter asiaticus (CLas, determined by Polymerase chain reactio...

  16. Characterization of microstructure, local deformation and microchemistry in Alloy 690 heat-affected zone and stress corrosion cracking in high temperature water

    NASA Astrophysics Data System (ADS)

    Lu, Zhanpeng; Chen, Junjie; Shoji, Tetsuo; Takeda, Yoichi; Yamazaki, Seiya

    2015-10-01

    With increasing the distance from the weld fusion line in an Alloy 690 heat-affected zone, micro-hardness decreases, kernel average misorientation decreases and the fraction of Σ3 boundaries increases. Chromium depletion at grain boundaries in the Alloy 690 heat-affected zone is less significant than that in an Alloy 600 heat-affected zone. Alloy 690 heat-affected zone exhibits much higher IGSCC resistance than Alloy 600 heat-affected zone in simulated pressurized water reactor primary water. Heavily cold worked Alloy 690 exhibits localized intergranular stress corrosion cracking. The effects of metallurgical and mechanical properties on stress corrosion cracking in Alloy 690 are discussed.

  17. Geochemical Factors Affecting the Behavior of Antimony, Cobalt, Europium, Technetium, and Uranium in Vadose Zone Sediments

    SciTech Connect

    Krupka, Kenneth M.; Serne, R. Jeffrey

    2002-12-15

    In developing the Field Investigation Report (FIR) for the Waste Management Area (WMA) S-SX at the Hanford Site, cesium-137 was the only gamma emitting radionuclide of concern (Knepp 2002). However, in WMA B-BX-BY, the spectral gamma logging data identify seven gamma emitting radionuclides, cesium-137, antimony-125, europium-152 and -154, cobalt-60, uranium-235 and -238 (DOE-GJPO 1998). The geochemical behaviors of several of these radionuclides, antimony-125 and the two europium isotopes, have not been extensively investigated at the Hanford Site. This task was initiated to assure that our understanding of the geochemical properties affecting the environmental behavior of these radionuclides reflects the current state of knowledge. A literature review was conducted to assess the important oxidation/reduction, aqueous speciation, solubility, and adsorption processes affecting the environmental behavior of antimony, cobalt, europium, technetium, and uranium in vadose zone sediments with low-organic matter content in semi-arid environments such as those at the Hanford Site. Technetium-99 was included in this task because of its importance in the long-term risk calculations. This report presents the results of this literature review.

  18. Effect of silicon contents on the microstructures and mechanical properties of heat affected zones for 9Cr2WVTa steels

    NASA Astrophysics Data System (ADS)

    Wang, Jian; Lu, Shanping; Rong, Lijian; Li, Dianzhong

    2016-03-01

    The weldability of 9Cr2WVTa steels with silicon content varying from 0.30 wt.% to 1.36 wt.% was studied to meet the requirement of Generation-Ⅳ nuclear reactor. Samples of enlarged HAZs were fabricated by a thermal-mechanical simulator based on the simulation and measurement of non-equilibrium phase transformation. The content of δ-ferrite in the HAZs increased with the silicon content and the peak temperature of welding thermal cycle. The impact toughness in the HAZs decreased in different degrees when the δ-ferrite exhibits stripe (lower than 4.82%) or blocky types (higher than 4.82%). Post weld heat treatment (PWHT) has a significant role on improving the toughness. Adding silicon content increased the volume of δ-ferrite and therefore, decreased the tensile strength of the HAZs for 9Cr2WVTa steels. Silicon also as solid solution strengthening element increased the tensile strength. The 9Cr2WVTa steel has good weldability when the silicon content is lower than 0.60 wt.%.

  19. Direct Observations of the (Alpha to Gamma) Transformation at Different Input Powers in the Heat Affected Zone of 1045 C-Mn Steel Arc Welds Observed by Spatially Resolved X-Ray Diffraction

    SciTech Connect

    Palmer, T A; Elmer, J W

    2005-03-16

    Spatially Resolved X-Ray Diffraction (SRXRD) experiments have been performed during Gas Tungsten Arc (GTA) welding of AISI 1045 C-Mn steel at input powers ranging from 1000 W to 3750 W. In situ diffraction patterns taken at discreet locations across the width of the heat affected zone (HAZ) near the peak of the heating cycle in each weld show regions containing austenite ({gamma}), ferrite and austenite ({alpha}+{gamma}), and ferrite ({alpha}). Changes in input power have a demonstrated effect on the resulting sizes of these regions. The largest effect is on the {gamma} phase region, which nearly triples in width with increasing input power, while the width of the surrounding two phase {alpha}+{gamma} region remains relatively constant. An analysis of the diffraction patterns obtained across this range of locations allows the formation of austenite from the base metal microstructure to be monitored. After the completion of the {alpha} {yields} {gamma} transformation, a splitting of the austenite peaks is observed at temperatures between approximately 860 C and 1290 C. This splitting in the austenite peaks results from the dissolution of cementite laths originally present in the base metal pearlite, which remain after the completion of the {alpha} {yields} {gamma} transformation, and represents the formation of a second more highly alloyed austenite constituent. With increasing temperatures, carbon, originally present in the cementite laths, diffuses from the second newly formed austenite constituent to the original austenite constituent. Eventually, a homogeneous austenitic microstructure is produced at temperatures of approximately 1300 C and above, depending on the weld input power.

  20. 30 CFR 47.1 - Purpose of a HazCom standard; applicability.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Purpose, Scope, Applicability, and Initial Miner... exposed, and other on-site operators whose miners can be exposed, about chemical hazards and...

  1. Factors Affecting Motivation and Job Satisfaction of Academic Staff of Universities in South-South Geopolitical Zone of Nigeria

    ERIC Educational Resources Information Center

    Osakwe, Regina N.

    2014-01-01

    This study determined the factors affecting motivation and job satisfaction of non-management academic staff of universities in South-South geopolitical zone of Nigeria. It employed an expost-facto research design. Three research questions and two hypotheses were raised for the study. A sample of four hundred and fifty non-management academic…

  2. Effect of acicular ferrite formation on grain refinement in the coarse-grained region of heat-affected zone

    SciTech Connect

    Wan, X.L.; Wei, R.; Wu, K.M.

    2010-07-15

    The microstructure of acicular ferrite and its formation for the grain refinement of coarse-grained region of heat-affected zone of high strength low-alloy bainite steels were studied using three-dimensional reconstruction technique. Crystallographic grain size was analyzed by means of electron backscatter diffraction. It was revealed that the microstructure in the coarse-grained region of the heat-affected zone consisted of predominantly bainite packets and a small proportion of acicular ferrite. Acicular ferrite was of lath or plate-like rather than needle or rod-like morphology. Tempering of the coarse-grained region of heat-affected zone showed that the acicular ferrite was more stable than the bainite, indicating that the acicular ferrite was formed prior to bainite. The acicular ferrite laths or plates divided the prior austenite grains into smaller and separate regions, and confining the bainite transformed at lower temperatures in the smaller regions and hence leading to the grain refinement in the coarse-grained region of the heat-affected zone.

  3. Factors affecting the dynamics of the honeybee (Apis mellifera) hybrid zone of South Africa.

    PubMed

    Beekman, M; Allsopp, M H; Wossler, T C; Oldroyd, B P

    2008-01-01

    Hybrid zones are found wherever two populations distinguishable on the basis of heritable characters overlap spatially and temporally and hybridization occurs. If hybrids have lower fitness than the parental types a tension zone may emerge, in which there is a barrier to gene flow between the two parental populations. Here we discuss a hybrid zone between two honeybee subspecies, Apis mellifera capensis and A. m. scutellata and argue that this zone is an example of a tension zone. This tension zone is particularly interesting because A. m. capensis can be a lethal social parasite of A. m. scutellata. However, despite its parasitic potential, A. m. capensis appears to be unable to increase its natural range unassisted. We propose three interlinked mechanisms that could maintain the South African honeybee hybrid zone: (1) low fitness of intercrossed and genetically mixed colonies arising from inadequate regulation of worker reproduction; (2) higher reproductive success of A. m. scutellata via both high dispersal rates into the hybrid zone and increased competitiveness of males, countered by (3) the parasitic nature of A. m. capensis.

  4. Factors affecting carbon-14 activity of unsaturated zone CO2 and implications for groundwater dating

    NASA Astrophysics Data System (ADS)

    Wood, Cameron; Cook, Peter G.; Harrington, Glenn A.; Meredith, Karina; Kipfer, Rolf

    2014-11-01

    Unsaturated zone processes may influence the carbon-14 (14C) activity of infiltrating groundwater and thus introduce error in derived groundwater residence times. However unsaturated zone 14C activities are rarely measured and there is little understanding of how they may vary spatially in a groundwater basin. In this study we measured 14C activity in unsaturated zone gas at five sites with different watertable depths (8.2-31.5 m) in the arid Ti Tree Basin, central Australia. We observed a relatively uniform decrease in 14C activity of unsaturated zone gas with depth at most sites, with variation in unsaturated zone depths leading to variation in 14C activities directly above the watertable at each site (ranging from 54 to 106 percent Modern Carbon (pMC)). Through modelling we show that the profiles are influenced by CO2 production at different depths from sources with different isotopic ratios, including production of ‘modern' CO2 in the root zone and production of ‘old' CO2 above the watertable. Scenario modelling showed that these processes are independent of recharge when recharge is low (0-10 mm y-1) but that higher recharge rates (>100 mm y-1) result in more advective transport of atmospheric CO2 to the watertable. The variation in 14C above the watertable was more sensitive to watertable depth and shallow and deep CO2 production rates. These findings offer insight into how unsaturated zone 14C activities may vary spatially and provide guidance as to when 14C depletion in unsaturated zone CO2 may become important for groundwater dating, particularly in arid settings.

  5. Mechanisms affecting the infiltration and distribution of ethanol-blended gasoline in the vadose zone.

    PubMed

    McDowell, Cory J; Powers, Susan E

    2003-05-01

    One- and two-dimensional experiments were conducted to examine differences in the behavior of gasoline and gasohol (10% ethanol by volume) as they infiltrate through the unsaturated zone and spread at the capillary fringe. Ethanol in the spilled gasohol quickly partitions into the residual water in the vadose zone and is retained there as the gasoline continues to infiltrate. Under the conditions tested, over 99% of the ethanol was initially retained in the vadose zone. Depending on the volume of gasoline spilled and the depth to the water table, this causes an increase in the aqueous-phase saturation and relative permeability, thus allowing the ethanol-laden water to drain into the gasoline pool. Under the conditions tested, the presence of ethanol does not have a significant impact on the overall size or shape of the resulting gasoline pool at the capillary fringe. Residual gasoline saturations in the vadose zone were significantly reduced however because of reduced surface and interfacial tensions associated with high ethanol concentrations. The flux of ethanol in the effluent of the column ranged from 1.4 x 10(-4) to 4.5 x 10(-7) g/(cm2 min) with the LNAPL and from 6 x 10(-3) to 3.0 x 10(-4) g/(cm2 min) after water was introduced to simulate rain infiltration. The experimental results presented here illustrate that the dynamic effects of ethanol partitioning into the aqueous phase in the vadose zone create an initial condition that is significantly different than previously understood.

  6. Visualization of microcrack anisotropy in granite affected by afault zone, using confocal laser scanning microscope

    SciTech Connect

    Onishi, Celia T.; Shimizu, Ichiko

    2004-01-02

    Brittle deformation in granite can generate a fracture system with different patterns. Detailed fracture analyses at both macroscopic and microscopic scales, together with physical property data from a drill-core, are used to classify the effects of reverse fault deformation in four domains: (1) undeformed granite, (2) fractured granite with cataclastic seams, (3) fractured granite from the damage zone, and (4) foliated cataclasite from the core of the fault. Intact samples from two orthogonal directions, horizontal (H) and vertical (V), from the four domains indicate a developing fracture anisotropy toward the fault, which is highly developed in the damage zone. As a specific illustration of this phenomenon, resin impregnation, using a confocal laser scanning microscope (CLSM) technique is applied to visualize the fracture anisotropy developed in the Toki Granite, Japan. As a result, microcrack networks have been observed to develop in H sections and elongate open cracks in V sections, suggesting that flow pathways can be determined by deformation.

  7. Determination of elastoplastic mechanical properties of the weld and heat affected zone metals in tailor-welded blanks by nanoindentation test

    NASA Astrophysics Data System (ADS)

    Ma, Xiangdong; Guan, Yingping; Yang, Liu

    2015-09-01

    The elastoplastic mechanical properties of the weld and heat affected zone metals have comparatively major impact on the forming process of tailor-welded blanks. A few scholars investigated the elastoplastic mechanical properties of the weld and heat affected zone, but they only simply assumed that it was a uniform distribution elastoplastic material different from the base materials. Four types of tailor-welded blanks which consist of ST12 and 304 stainless steel plates are selected as the research objects, the elastoplastic mechanical properties of the tailor-welded blanks weld and heat affected zone metals are obtained based on the nanoindentation tests, and the Erichsen cupping tests are conducted by combining numerical simulation with physical experiment. The nanoindentation tests results demonstrate that the elastoplastic mechanical properties of the weld and heat affected zone metals are not only different from the base materials, but also varying between the weld metals and the heat affected zone metals. Comparing the Erichsen cupping test resulted from numerical with that from experimental method, it is found that the numerical value of Erichsen cupping test which consider the elastoplastic mechanical properties of the weld and heat affected zone metals have a good agreement with the experimental result, and the relative error is only 4.8%. The proposed research provides good solutions for the inhomogeneous elastoplastic mechanical properties of the tailor-welded blanks weld and heat affected zone metals, and improves the control performance of tailor-welded blanks forming accuracy.

  8. 30 CFR 47.91 - Exemptions from the HazCom standard.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ionizing or non-ionizing radiation, such as alpha or gamma, microwaves, or x-rays. Wood or wood products...—Chemicals and Products Exempt from this HazCom Standard Exemption Conditions for exemption Article If, under..., such as poisonous plants, insects, and micro-organisms. Consumer product or hazardous...

  9. 30 CFR 47.91 - Exemptions from the HazCom standard.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ionizing or non-ionizing radiation, such as alpha or gamma, microwaves, or x-rays. Wood or wood products...—Chemicals and Products Exempt from this HazCom Standard Exemption Conditions for exemption Article If, under..., such as poisonous plants, insects, and micro-organisms. Consumer product or hazardous...

  10. 30 CFR 47.91 - Exemptions from the HazCom standard.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ionizing or non-ionizing radiation, such as alpha or gamma, microwaves, or x-rays. Wood or wood products...—Chemicals and Products Exempt from this HazCom Standard Exemption Conditions for exemption Article If, under..., such as poisonous plants, insects, and micro-organisms. Consumer product or hazardous...

  11. 76 FR 21410 - Proposed Extension of Existing Information Collection; Hazard Communication (HazCom)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-15

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Mine... Communication (HazCom) AGENCY: Mine Safety and Health Administration, Department of Labor. ACTION: Notice of... respondents can be properly assessed. Currently, the Mine Safety and Health Administration (MSHA)...

  12. Enhancement of Heat-Affected Zone Toughness of a Low Carbon Steel by TiN Particle

    NASA Astrophysics Data System (ADS)

    Zhang, Yu; Li, Xiaobao; Ma, Han

    2016-08-01

    Enhancement of heat-affected zone toughness of a weight percentage of 0.014 pct Ti-bearing low carbon steel by TiN particle was investigated. An increase in nitrogen weight percentage from 0.0031 to 0.0083 pct results in increasing of number density of TiN precipitates from 4 × 103 to 3 × 105/mm2, and reduces prior austenite grain size from 850 to 350 μm with a soaking of 1673 K (1400 °C) for 2000 seconds. Effective refinement of austenite grain prohibits formation of ferrite side plate and/or upper bainite, and densely distributed TiN particles promote intra-granular ferrite formation, which is accompanied by an increase of 40 K to 60 K (40 °C to 60 °C) in austenite decomposition temperature during continuous cooling process. The changes in transformed products improved impact toughness of heat-affected zone efficiently, ex., increase absorbed energy of less than 42 J to more than 320 J with a simulated t 8/5 of 550 seconds.

  13. Waste storage in the vadose zone affected by water vapor condensation and leaching

    SciTech Connect

    Cary, J.W.; Gee, G.W.; Whyatt, G.A.

    1990-08-01

    One of the major concerns associated with waste storage in the vadose zone is that toxic materials may somehow be leached and transported by advecting water down to the water table and reach the accessible environment through either a well or discharge to a river. Consequently, care is taken to provide barriers over and around the storage sites to reduce contact between infiltrating water and the buried waste form. In some cases, it is important to consider the intrusion of water vapor as well as water in the liquid phase. Water vapor diffuses through porous material along vapor pressure gradients. A slightly low temperature, or the presence of water-soluble components in the waste, favors water condensation resulting in leaching of the waste form and advection of water-soluble components to the water table. A simple analysis is presented that allows one to estimate the rate of vapor condensation as a function of waste composition and backfill materials. An example using a waste form surrounded by concrete and gravel layers is presented. The use of thermal gradients to offset condensation effects of water-soluble components in the waste form is discussed. Thermal gradients may be controlled by design factors that alter the atmospheric energy exchange across the soil surface or that interrupt the geothermal heat field. 7 refs., 2 figs., 1 tab.

  14. Factors Affecting the Latitudinal Location of the Intertropical Convergence Zone in a GCM

    NASA Technical Reports Server (NTRS)

    Chao, Winston C.; Chen, Baode

    2002-01-01

    The dominant role of the latitudinal peak of the sea surface temperature (SST) in determining the latitudinal location of the intertropical convergence zone (ITCZ) is well-known. However, the roles of the other factors are less well-known and are the topic of this study. These other factors include the inertial stability, the interaction between convection and surface fluxes and the interaction between convection and radiation. Since these interactions involve convection, in a model they involve the cumulus parameterization scheme. These factors are studied with a general circulation model with uniform SST and solar angle. Under the aforementioned model settings, the latitudinal location of the ITCZ is the latitude where the balance of two types of attraction on the ITCZ, both due to earth's rotation, exists. Directly related to the Coriolis parameter, the first type pulls the ITCZ toward the equator and is not sensitive to model design changes. Related to the convective circulation, the second type pulls the ITCZ poleward and is sensitive to model design changes. Due to the shape and the magnitude of the attractors, the balance of the two types of attractions is reached either at the equator or more than 10 degrees away from the equator. The former case results in a single ITCZ over the equator and the latter case a double ITCZ straddling the equator.

  15. Health in the hot zone - How could global warming affect humans?

    SciTech Connect

    Monastersky, R.

    1996-04-06

    A soon-to-be-released report from the World Health Organization examines the health effects of global warming, calling climate change one of the largest public health challenges for the upcoming century. The issue extends beyond tropical illness: deaths caused directly by heat, dwindling agricultural yields etc. could all affect human health. This article looks at the following health related effects and gives an overview of the scientific information available on each: temperature and mortality; tropical trouble, including vecorborne diseases and increase in susceptable populations; and waterborne problems such as cholera, harmful algal bloomes, food shortages.

  16. Statistical analysis of factors affecting landslide distribution in the new Madrid seismic zone, Tennessee and Kentucky

    USGS Publications Warehouse

    Jibson, R.W.; Keefer, D.K.

    1989-01-01

    More than 220 large landslides along the bluffs bordering the Mississippi alluvial plain between Cairo, Ill., and Memphis, Tenn., are analyzed by discriminant analysis and multiple linear regression to determine the relative effects of slope height and steepness, stratigraphic variation, slope aspect, and proximity to the hypocenters of the 1811-12 New Madrid, Mo., earthquakes on the distribution of these landslides. Three types of landslides are analyzed: (1) old, coherent slumps and block slides, which have eroded and revegetated features and no active analogs in the area; (2) old earth flows, which are also eroded and revegetated; and (3) young rotational slumps, which are present only along near-river bluffs, and which are the only young, active landslides in the area. Discriminant analysis shows that only one characteristic differs significantly between bluffs with and without young rotational slumps: failed bluffs tend to have sand and clay at their base, which may render them more susceptible to fluvial erosion. Bluffs having old coherent slides are significantly higher, steeper, and closer to the hypocenters of the 1811-12 earthquakes than bluffs without these slides. Bluffs having old earth flows are likewise higher and closer to the earthquake hypocenters. Multiple regression analysis indicates that the distribution of young rotational slumps is affected most strongly by slope steepness: about one-third of the variation in the distribution is explained by variations in slope steepness. The distribution of old coherent slides and earth flows is affected most strongly by slope height, but the proximity to the hypocenters of the 1811-12 earthquakes also significantly affects the distribution. The results of the statistical analyses indicate that the only recently active landsliding in the area is along actively eroding river banks, where rotational slumps formed as bluffs are undercut by the river. The analyses further indicate that the old coherent slides

  17. Remote sensing for assessing the zone of benefit where deep drains improve productivity of land affected by shallow saline groundwater.

    PubMed

    Kobryn, H T; Lantzke, R; Bell, R; Admiraal, R

    2015-03-01

    The installation of deep drains is an engineering approach to remediate land salinised by the influence of shallow groundwater. It is a costly treatment and its economic viability is, in part, dependent on the lateral extent to which the drain increases biological productivity by lowering water tables and soil salinity (referred to as the drains' zone of benefit). Such zones may be determined by assessing the biological productivity response of adjacent vegetation over time. We tested a multi-temporal satellite remote sensing method to analyse temporal and spatial changes in vegetation condition surrounding deep drainage sites at five locations in the Western Australian wheatbelt affected by dryland salinity-Morawa, Pithara, Beacon, Narembeen and Dumbleyung. Vegetation condition as a surrogate for biological productivity was assessed by Normalised Difference Vegetation Index (NDVI) during the peak growing season. Analysis was at the site scale within a 1000 m buffer zone from the drains. There was clear evidence of NDVI increasing with elevation, slope and distance from the drain. After accounting for elevation, slope and distance from the drain, there was a significant increase in NDVI across the five locations after installation of deep drains. Changes in NDVI after drainage were broadly consistent with measured changes at each site in groundwater levels after installation of the deep drains. However, this study assessed the lateral extent of benefit for biological productivity and gave a measure of the area of benefit along the entire length of the drain. The method demonstrated the utility of spring NDVI images for rapid and relatively simple assessment of the change in site condition after implementation of drainage, but approaches for further improvement of the procedure were identified.

  18. Linking river, floodplain, and vadose zone hydrology to improve restoration of a coastal river affected by saltwater intrusion.

    PubMed

    Kaplan, D; Muñoz-Carpena, R; Wan, Y; Hedgepeth, M; Zheng, F; Roberts, R; Rossmanith, R

    2010-01-01

    Floodplain forests provide unique ecological structure and function, which are often degraded or lost when watershed hydrology is modified. Restoration of damaged ecosystems requires an understanding of surface water, groundwater, and vadose (unsaturated) zone hydrology in the floodplain. Soil moisture and porewater salinity are of particular importance for seed germination and seedling survival in systems affected by saltwater intrusion but are difficult to monitor and often overlooked. This study contributes to the understanding of floodplain hydrology in one of the last bald cypress [Taxodium distichum (L.) Rich.] floodplain swamps in southeast Florida. We investigated soil moisture and porewater salinity dynamics in the floodplain of the Loxahatchee River, where reduced freshwater flow has led to saltwater intrusion and a transition to salt-tolerant, mangrove-dominated communities. Twenty-four dielectric probes measuring soil moisture and porewater salinity every 30 min were installed along two transects-one in an upstream, freshwater location and one in a downstream tidal area. Complemented by surface water, groundwater, and meteorological data, these unique 4-yr datasets quantified the spatial variability and temporal dynamics of vadose zone hydrology. Results showed that soil moisture can be closely predicted based on river stage and topographic elevation (overall Nash-Sutcliffe coefficient of efficiency = 0.83). Porewater salinity rarely exceeded tolerance thresholds (0.3125 S m(-1)) for bald cypress upstream but did so in some downstream areas. This provided an explanation for observed vegetation changes that both surface water and groundwater salinity failed to explain. The results offer a methodological and analytical framework for floodplain monitoring in locations where restoration success depends on vadose zone hydrology and provide relationships for evaluating proposed restoration and management scenarios for the Loxahatchee River.

  19. Modeling phase transformation behavior during thermal cycling in the heat-affected zone of stainless steel welds

    SciTech Connect

    Vitek, J.M.; Iskander, Y.S.; David, S.A.

    1995-12-31

    An implicit finite-difference analysis was used to model the diffusion-controlled transformation behavior in a ternary system. The present analysis extends earlier work by examining the transformation behavior under the influence of multiple thermal cycles. The analysis was applied to the Fe-Cr-Ni ternary system to simulate the microstructural development in austenitic stainless steel welds. The ferrite-to-austenite transformation was studied in an effort to model the response of the heat-affected zone to multiple thermal cycles experienced during multipass welding. Results show that under some conditions, a transformation ``inertia`` exists that delays the system`s response when changing from cooling to heating. Conditions under which this ``inertia`` is most influential were examined. It was also found that under some conditions, the transformation behavior does not follow the equilibrium behavior as a function of temperature. Results also provide some insight into effect of composition distribution on transformation behavior.

  20. Factors affecting the quality of fish caught by Native Americans in the Zone 6 fishery 1991 through 1993

    SciTech Connect

    Abernethy, C.S.

    1994-09-01

    A program to monitor the salmon and steelhead (Oncorhynchus spp.) fishery in the lower Columbia River (Zone 6 fishery) was initiated in 1991 to respond to questions and comments frequently made by Native Americans at public meetings. Native Americans were concerned that the quality of the Columbia River had deteriorated and that the poor environmental conditions had affected the health and quality of fish they relied on for subsistence, ceremonial, religious, and commercial purposes. They also feared that eating contaminated fish might endanger the health of their children and future generations. Operations at the Hanford Site were listed as one of many causes of the deteriorating environment. Fisheries pathologists concluded that most of the external symptoms on fish were related to bacterial infection of gill net abrasions and pre-spawning trauma, and were not caused by pollution or contamination of the Columbia River. The pathologists also stated that consumption of the fish posed no threat to human consumers.

  1. Dissolved barium behavior in Louisiana Shelf waters affected by the Mississippi/Atchafalaya River mixing zone

    NASA Astrophysics Data System (ADS)

    Joung, DongJoo; Shiller, Alan M.

    2014-09-01

    a proxy for paleo-salinity changes. Barium input to bottom waters and the extent to which this is natural or anthropogenically-affected is a particular source of uncertainty. Thus, as is the case with nearly all paleoceanographic proxies, the planktonic foraminiferal Ba/Ca ratio should be used in conjunction with other constraining proxies.

  2. Microstructural studies and crystallographic orientation of different zones and δ-hydrides in resistance welded Zircaloy-4 sheets

    NASA Astrophysics Data System (ADS)

    Kiran Kumar, N. A. P.; Szpunar, Jerzy. A.; He, Zhang

    2011-07-01

    The cold worked stress relieved (CWSR) Zircaloy-4 sheet used as endplate in nuclear fuel bundle is resistance welded with an endcap in argon environment. Later the welded sample is hydrided in a gaseous atmosphere at 400 °C. Optical microscopy (OM), electron backscatter diffraction (EBSD) and X-ray diffraction (XRD) were used to examine the morphology and crystal orientation of the hydrides. The microstructural changes in different areas of the weld zone, heat affected zone (HAZ) and the as-received zone were analyzed using EBSD technique. Optical examination showed complete random morphological orientation of hydrides and predominantly basket-weave structure in the weld zone, with very few colonies of parallel plate structures. Variant selection for α-phase formation inside prior β-grains was identified at the weld centre. As we move from the weld centre to the as-received zone, the variant selection is found to be less probable. The δ-hydride platelets at the weld zone were always found to be growing perpendicular to the α-colonies having angular difference of 60-63° and follow (0 0 0 1) α-Zr//{1 1 1}δ-ZrH 1.5 orientation relationship with the zirconium matrix. Proposed description of complex distribution of hydrides and alloy microstructure at the weld and heat affected zone will contribute to a better understanding of mechanisms of failure of fuel cladding in various types of nuclear reactors.

  3. Neural Network approach to assess the thermal affected zone around the injection well in a groundwater heat pump system

    NASA Astrophysics Data System (ADS)

    Lo Russo, Stefano; Taddia, Glenda; Verda, Vittorio

    2014-05-01

    The common use of well doublets for groundwater-sourced heating or cooling results in a thermal plume of colder or warmer re-injected groundwater known as the Thermal Affected Zone(TAZ). The plumes may be regarded either as a potential anthropogenic geothermal resource or as pollution, depending on downstream aquifer usage. A fundamental aspect in groundwater heat pump (GWHP) plant design is the correct evaluation of the thermally affected zone that develops around the injection well. Temperature anomalies are detected through numerical methods. Crucial elements in the process of thermal impact assessment are the sizes of installations, their position, the heating/cooling load of the building, and the temperature drop/increase imposed on the re-injected water flow. For multiple-well schemes, heterogeneous aquifers, or variable heating and cooling loads, numerical models that simulate groundwater and heat transport are needed. These tools should consider numerous scenarios obtained considering different heating/cooling loads, positions, and operating modes. Computational fluid dynamic (CFD) models are widely used in this field because they offer the opportunity to calculate the time evolution of the thermal plume produced by a heat pump, depending on the characteristics of the subsurface and the heat pump. Nevertheless, these models require large computational efforts, and therefore their use may be limited to a reasonable number of scenarios. Neural networks could represent an alternative to CFD for assessing the TAZ under different scenarios referring to a specific site. The use of neural networks is proposed to determine the time evolution of the groundwater temperature downstream of an installation as a function of the possible utilization profiles of the heat pump. The main advantage of neural network modeling is the possibility of evaluating a large number of scenarios in a very short time, which is very useful for the preliminary analysis of future multiple

  4. A process model for the heat-affected zone microstructure evolution in duplex stainless steel weldments: Part I. The model

    SciTech Connect

    Hemmer, H.; Grong, O.

    1999-11-01

    The present investigation is concerned with modeling of the microstructure evolution in duplex stainless steels under thermal conditions applicable to welding. The important reactions that have been modeled are the dissolution of austenite during heating, subsequent grain growth in the delta ferrite regime, and finally, the decomposition of the delta ferrite to austenite during cooling. As a starting point, a differential formulation of the underlying diffusion problem is presented, based on the internal-state variable approach. These solutions are later manipulated and expressed in terms of the Scheil integral in the cases where the evolution equation is separable or can be made separable by a simple change of variables. The models have then been applied to describe the heat-affected zone microstructure evolution during both thick-plate and thin-plate welding of three commercial duplex stainless steel grades: 2205, 2304, and 2507. The results may conveniently be presented in the form of novel process diagrams, which display contours of constant delta ferrite grain size along with information about dissolution and reprecipitation of austenite for different combinations of weld input energy and peak temperature. These diagrams are well suited for quantitative readings and illustrate, in a condensed manner, the competition between the different variables that lead to structural changes during welding of duplex stainless steels.

  5. Green reconstruction of the tsunami-affected areas in India using the integrated coastal zone management concept.

    PubMed

    Sonak, Sangeeta; Pangam, Prajwala; Giriyan, Asha

    2008-10-01

    A tsunami, triggered by a massive undersea earthquake off Sumatra in Indonesia, greatly devastated the lives, property and infrastructure of coastal communities in the coastal states of India, Andaman and Nicobar Islands, Indonesia, Sri Lanka, Malaysia and Thailand. This event attracted the attention of environmental managers at all levels, local, national, regional and global. It also shifted the focus from the impact of human activities on the environment to the impacts of natural hazards. Recovery/reconstruction of these areas is highly challenging. A clear understanding of the complex dynamics of the coast and the types of challenges faced by the several stakeholders of the coast is required. Issues such as sustainability, equity and community participation assume importance. The concept of ICZM (integrated coastal zone management) has been effectively used in most parts of the world. This concept emphasizes the holistic assessment of the coast and a multidisciplinary analysis using participatory processes. It integrates anthropocentric and eco-centric approaches. This paper documents several issues involved in the recovery of tsunami-affected areas and recommends the application of the ICZM concept to the reconstruction efforts. PMID:17544565

  6. A process model for the heat-affected zone microstructure evolution in duplex stainless steel weldments: Part I. the model

    NASA Astrophysics Data System (ADS)

    Hemmer, H.; Grong, Ø.

    1999-11-01

    The present investigation is concerned with modeling of the microstructure evolution in duplex stainless steels under thermal conditions applicable to welding. The important reactions that have been modeled are the dissolution of austenite during heating, subsequent grain growth in the delta ferrite regime, and finally, the decomposition of the delta ferrite to austenite during cooling. As a starting point, a differential formulation of the underlying diffusion problem is presented, based on the internal-state variable approach. These solutions are later manipulated and expressed in terms of the Scheil integral in the cases where the evolution equation is separable or can be made separable by a simple change of variables. The models have then been applied to describe the heat-affected zone microstructure evolution during both thick-plate and thin-plate welding of three commercial duplex stainless steel grades: 2205, 2304, and 2507. The results may conveniently be presented in the form of novel process diagrams, which display contours of constant delta ferrite grain size along with information about dissolution and reprecipitation of austenite for different combinations of weld input energy and peak temperature. These diagrams are well suited for quantitative readings and illustrate, in a condensed manner, the competition between the different variables that lead to structural changes during welding of duplex stainless steels.

  7. Green reconstruction of the tsunami-affected areas in India using the integrated coastal zone management concept.

    PubMed

    Sonak, Sangeeta; Pangam, Prajwala; Giriyan, Asha

    2008-10-01

    A tsunami, triggered by a massive undersea earthquake off Sumatra in Indonesia, greatly devastated the lives, property and infrastructure of coastal communities in the coastal states of India, Andaman and Nicobar Islands, Indonesia, Sri Lanka, Malaysia and Thailand. This event attracted the attention of environmental managers at all levels, local, national, regional and global. It also shifted the focus from the impact of human activities on the environment to the impacts of natural hazards. Recovery/reconstruction of these areas is highly challenging. A clear understanding of the complex dynamics of the coast and the types of challenges faced by the several stakeholders of the coast is required. Issues such as sustainability, equity and community participation assume importance. The concept of ICZM (integrated coastal zone management) has been effectively used in most parts of the world. This concept emphasizes the holistic assessment of the coast and a multidisciplinary analysis using participatory processes. It integrates anthropocentric and eco-centric approaches. This paper documents several issues involved in the recovery of tsunami-affected areas and recommends the application of the ICZM concept to the reconstruction efforts.

  8. Recovery approach affects soil quality in the water level fluctuation zone of the Three Gorges Reservoir, China: implications for revegetation.

    PubMed

    Ye, Chen; Cheng, Xiaoli; Zhang, Quanfa

    2014-02-01

    Plants in the water level fluctuation zone of the Three Gorges Reservoir Region disappeared due to winter-flooding and prolonged inundation. Revegetation (plantation and natural recovery) have been promoted to restore and protect the riparian ecosystem in recent years. Revegetation may affect soil qualities and have broad important implications both for ecological services and soil recovery. In this study, we investigated soil properties including soil pH values, bulk density, soil organic matter (SOM), soil nutrients and heavy metals, soil microbial community structure, microbial biomass, and soil quality index under plantation and natural recovery in the Three Gorges Reservoir Region. Most soil properties showed significant temporal and spatial variations in both the plantation and natural recovery areas. Higher contents of SOM and NO3-N were found in plantation area, while higher contents of soil pH values, bulk density, and total potassium were observed in the natural recovery area. However, there were no significant differences in plant richness and diversity and soil microbial community structure between the two restoration approaches. A soil quality index derived from SOM, bulk density, Zn, Cd, and Hg indicated that natural recovery areas with larger herbaceous coverage had more effective capacity for soil restoration. PMID:24019143

  9. Recovery approach affects soil quality in the water level fluctuation zone of the Three Gorges Reservoir, China: implications for revegetation.

    PubMed

    Ye, Chen; Cheng, Xiaoli; Zhang, Quanfa

    2014-02-01

    Plants in the water level fluctuation zone of the Three Gorges Reservoir Region disappeared due to winter-flooding and prolonged inundation. Revegetation (plantation and natural recovery) have been promoted to restore and protect the riparian ecosystem in recent years. Revegetation may affect soil qualities and have broad important implications both for ecological services and soil recovery. In this study, we investigated soil properties including soil pH values, bulk density, soil organic matter (SOM), soil nutrients and heavy metals, soil microbial community structure, microbial biomass, and soil quality index under plantation and natural recovery in the Three Gorges Reservoir Region. Most soil properties showed significant temporal and spatial variations in both the plantation and natural recovery areas. Higher contents of SOM and NO3-N were found in plantation area, while higher contents of soil pH values, bulk density, and total potassium were observed in the natural recovery area. However, there were no significant differences in plant richness and diversity and soil microbial community structure between the two restoration approaches. A soil quality index derived from SOM, bulk density, Zn, Cd, and Hg indicated that natural recovery areas with larger herbaceous coverage had more effective capacity for soil restoration.

  10. A SYNCHROTRON DIFFRACTION STUDY OF TRANSFORMATION BEHAVIOUR IN 9 CR STEELS USING SIMULATED WELD HEAT-AFFECTED ZONE CONDITIONS

    SciTech Connect

    Santella, Michael L; Specht, Eliot D; Shingledecker, John P; Abe, Fujio

    2007-01-01

    Synchrotron diffraction experiments were conducted to examine the real-time transformation behaviours of an ex-perimental 9Cr-3W-3Co-NbV steel with high B and low N (N130B), and the commercial P92 steel under simulated weld heat-affected zone thermal cycles. When heated to peak temperatures near 1100 C, both steels rapidly trans-formed from ferrite to 100% austenite. During cooling, both transformed to martensite near 400 C. Both steels also retained untransformed austenite: 1.7% in N130B, and 5.8% in P92. The N130B was also heated to about 60 C above its A3 of 847 C. About 56% of the original ferrite never transformed to austenite. During cooling an additional 21% of ferrite and 23% of martensite formed. It retained no austenite. The P92 was heated to just above its A3 of 889 C. About 15% of the original ferrite never transformed to austenite. During cooling an additional 22% of ferrite and 60% of martensite formed. This steel retained about 2.3% austenite. Metallographic examina-tions indicated that the M23C6 in N130B was much more stable than that in P92 for heating to the lower peak tem-peratures. Analysis using equilibrium thermodynamics suggested that the more stable M23C6 in N130B could raise its apparent A3 by sequestering C. This could cause the ferrite-austenite transformation to appear sluggish. Ther-modynamic analysis also indicated that the M23C6 in N130B contained about 3.9 at% B compared to about 0.08 at% B in that of P92. In contrast, the refractory metal element content of the M23C6 was predicted to be higher in P92.

  11. Contents and toxicity of heavy metals in soils of the zone affected by aerial emissions from the Severonikel Enterprise

    NASA Astrophysics Data System (ADS)

    Evdokimova, G. A.; Kalabin, G. V.; Mozgova, N. P.

    2011-02-01

    In 2009, the zoning of the terrestrial ecosystems in the area exposed to aerial emissions from the Severonikel Enterprise (Murmansk oblast) was performed on the basis of the parameters characterizing the state of the soils, including the contents of the main heavy metal pollutants and exchangeable calcium and magnesium, the soils' pH, the ratio of the organic to mineral soil components, and the state of the soils' microbiota. Three zones differing in the degree of the soil pollution were delimited. These were the zones of heavy, moderate, and weak pollution, which extended for up to 3, 25, and 50 km from the emission source in the prevailing wind direction. The data on the amount of bacterial and fungal biomass provided evidence of the profound degradation of the soils in the heavily polluted zone. In particular, the biomass of the soil microbiota, including its prokaryotic and eukaryotic components, was two to six times lower in this zone than in the background (control) area. The soils of the heavily polluted zone can be classified as strongly toxic for plants, and most of the soils of the moderately polluted zone also fall into the same category.

  12. Calibrated heat flow model for the determination of different heat-affected zones in single-pass laser-cut CFRP using a cw CO2 laser

    NASA Astrophysics Data System (ADS)

    Mucha, P.; Berger, P.; Weber, R.; Speker, N.; Sommer, B.; Graf, T.

    2015-03-01

    Laser machining has great potential for automated manufacturing of parts made of carbon-fiber-reinforced plastic (CFRP) due to the nearly force and tool-wear free processing. The high vaporization temperatures and the large heat conductivity of the carbon fibers, however, lead to unintentional heat conduction into the material causing damage in zones close to the process. In this paper, the matrix damage zone (MDZ) is subdivided into a matrix sublimation zone (MSZ) where the matrix material was sublimated and a zone where the temperature temporarily exceeded a value causing structural damage in the matrix. In order to investigate the extent of these zones, a one-dimensional heat flow model was applied, which was calibrated by cutting experiments using temperature sensors embedded in the CFRP samples. The investigations showed that the extents of the MSZ and MDZ are dominated by a total interaction time, which includes the passage of the laser beam and the continued interaction of the cloud of hot ablation products with the carbon fibers at the kerf wall and that from a practical point of view, the experimentally determined effective heat conductivity is suitable for simple estimations of the heat-affected zones in CFRP.

  13. Isothermal Calorimetric Observations of the Affect of Welding on Compatibility of Stainless Steels with High-Test Hydrogen Peroxide Propellant

    NASA Technical Reports Server (NTRS)

    Gostowski, Rudy C.

    2002-01-01

    Compatibility is determined by the surface area, the chemical constituency and the surface finish of a material. In this investigation exposed area is obviously not a factor as the welded samples had a slightly smaller surface than the unwelded, but were more reactive. The chemical makeup of welded CRES 316L and welded CRES 304L have been observed in the literature to change from the parent material as chromium and iron are segregated in zones. In particular, the ratio of chromium to iron in CRES 316L increased from 0.260 to 0.79 in the heat affected zone (HAZ) of the weld and to 1.52 in the weld bead itself. In CRES 304L the ratio of chromium to iron increased from 0.280 to 0.44 in the HAZ and to 0.33 in the weld bead. It is possible that the increased reactivity of the welded samples and of those welded without purge gas is due to this segregation phenomenon. Likewise the reactivity increased in keeping with the greater roughness of the welded and welded without purge gas samples. Therefore enhanced roughness may also be responsible for the increased reactivity.

  14. Utilization of accident databases and fuzzy sets to estimate frequency of HazMat transport accidents.

    PubMed

    Qiao, Yuanhua; Keren, Nir; Mannan, M Sam

    2009-08-15

    Risk assessment and management of transportation of hazardous materials (HazMat) require the estimation of accident frequency. This paper presents a methodology to estimate hazardous materials transportation accident frequency by utilizing publicly available databases and expert knowledge. The estimation process addresses route-dependent and route-independent variables. Negative binomial regression is applied to an analysis of the Department of Public Safety (DPS) accident database to derive basic accident frequency as a function of route-dependent variables, while the effects of route-independent variables are modeled by fuzzy logic. The integrated methodology provides the basis for an overall transportation risk analysis, which can be used later to develop a decision support system.

  15. Utilization of accident databases and fuzzy sets to estimate frequency of HazMat transport accidents.

    PubMed

    Qiao, Yuanhua; Keren, Nir; Mannan, M Sam

    2009-08-15

    Risk assessment and management of transportation of hazardous materials (HazMat) require the estimation of accident frequency. This paper presents a methodology to estimate hazardous materials transportation accident frequency by utilizing publicly available databases and expert knowledge. The estimation process addresses route-dependent and route-independent variables. Negative binomial regression is applied to an analysis of the Department of Public Safety (DPS) accident database to derive basic accident frequency as a function of route-dependent variables, while the effects of route-independent variables are modeled by fuzzy logic. The integrated methodology provides the basis for an overall transportation risk analysis, which can be used later to develop a decision support system. PMID:19250750

  16. Aggregate-cement paste transition zone properties affecting the salt-frost damage of high-performance concretes

    SciTech Connect

    Cwirzen, Andrzej; Penttala, Vesa

    2005-04-01

    The influence of the cement paste-aggregate interfacial transition zone (ITZ) on the frost durability of high-performance silica fume concrete (HPSFC) has been studied. Investigation was carried out on eight non-air-entrained concretes having water-to-binder (W/B) ratios of 0.3, 0.35 and 0.42 and different additions of condensed silica fume. Studies on the microstructure and composition of the cement paste have been made by means of environmental scanning electron microscope (ESEM)-BSE, ESEM-EDX and mercury intrusion porosimetry (MIP) analysis. The results showed that the transition zone initiates and accelerates damaging mechanisms by enhancing movement of the pore solution within the concrete during freezing and thawing cycles. Cracks filled with ettringite were primarily formed in the ITZ. The test concretes having good frost-deicing salt durability featured a narrow transition zone and a decreased Ca/Si atomic ratio in the transition zone compared to the bulk cement paste. Moderate additions of silica fume seemed to densify the microstructure of the ITZ.

  17. A Thermal Physiological Comparison of Two HazMat Protective Ensembles With and Without Active Convective Cooling

    NASA Technical Reports Server (NTRS)

    Williamson, Rebecca; Carbo, Jorge; Luna, Bernadette; Webbon, Bruce W.

    1998-01-01

    Wearing impermeable garments for hazardous materials clean up can often present a health and safety problem for the wearer. Even short duration clean up activities can produce heat stress injuries in hazardous materials workers. It was hypothesized that an internal cooling system might increase worker productivity and decrease likelihood of heat stress injuries in typical HazMat operations. Two HazMat protective ensembles were compared during treadmill exercise. The different ensembles were created using two different suits: a Trelleborg VPS suit representative of current HazMat suits and a prototype suit developed by NASA engineers. The two life support systems used were a current technology Interspiro Spirolite breathing apparatus and a liquid air breathing system that also provided convective cooling. Twelve local members of a HazMat team served as test subjects. They were fully instrumented to allow a complete physiological comparison of their thermal responses to the different ensembles. Results showed that cooling from the liquid air system significantly decreased thermal stress. The results of the subjective evaluations of new design features in the prototype suit were also highly favorable. Incorporation of these new design features could lead to significant operational advantages in the future.

  18. Tomato growth as affected by root-zone temperature and the addition of gibberellic acid and kinetin to nutrient solutions

    NASA Technical Reports Server (NTRS)

    Bugbee, B.; White, J. W.; Salisbury, F. B. (Principal Investigator)

    1984-01-01

    The effect of root-zone temperature on young tomato plants (Lycopersicon esculentum Mill. cv. Heinz 1350) was evaluated in controlled environments using a recirculating solution culture system. Growth rates were measured at root-zone temperatures of 15 degrees, 20 degrees, 25 degrees, and 30 degrees C in a near optimum foliar environment. Optimum growth occurred at 25 degrees to 30 degrees during the first 4 weeks of growth and 20 degrees to 25 degrees during the 5th and 6th weeks. Growth was severely restricted at 15 degrees. Four concentrations of gibberellic acid (GA3) and kinetin were added to the nutrient solution in a separate trial; root-zone temperature was maintained at 15 degrees and 25 degrees. Addition of 15 micromoles GA3 to solutions increased specific leaf area, total leaf area, and dry weight production of plants in both temperature treatments. GA3-induced growth stimulation was greater at 15 degrees than at 25 degrees. GA3 may promote growth by increasing leaf area, enhancing photosynthesis per unit leaf area, or both. Kinetic was not useful in promoting growth at either temperature.

  19. Colloid formation and metal transport through two mixing zones affected by acid mine drainage near Silverton, Colorado

    USGS Publications Warehouse

    Schemel, L.E.; Kimball, B.A.; Bencala, K.E.

    2000-01-01

    Stream discharges and concentrations of dissolved and colloidal metals (Al, Ca, Cu, Fe, Mg, Mn, Pb, and Zn), SO4, and dissolved silica were measured to identify chemical transformations and determine mass transports through two mixing zones in the Animas River that receive the inflows from Cement and Mineral Creeks. The creeks were the dominant sources of Al, Cu, Fe, and Pb, whereas the upstream Animas River supplied about half of the Zn. With the exception of Fe, which was present in dissolved and colloidal forms, the metals were dissolved in the acidic, high-SO4 waters of Cement Creek (pH 3.8). Mixing of Cement Creek with the Animas River increased pH to near-neutral values and transformed Al and some additional Fe into colloids which also contained Cu and Pb. Aluminium and Fe colloids had already formed in the mildly acidic conditions in Mineral Creek (pH 6.6) upstream of the confluence with the Animas River. Colloidal Fe continued to form downstream of both mixing zones. The Fe- and Al-rich colloids were important for transport of Cu, Pb, and Zn, which appeared to have sorbed to them. Partitioning of Zn between dissolved and colloidal phases was dependent on pH and colloid concentration. Mass balances showed conservative transports for Ca, Mg, Mn, SO4, and dissolved silica through the two mixing zones and small losses (< 10%) of colloidal Al, Fe and Zn from the water column.

  20. High hydrogen peroxide concentration in the feed-zone affects bioreactor cell productivity with liquid phase oxygen supply strategy.

    PubMed

    Sarkar, Pritish; Ghosh, Kaushik; Suraishkumar, G K

    2008-06-01

    Liquid phase oxygen supply strategy (LPOS), in which hydrogen peroxide (H(2)O(2)) is used to supply oxygen to the bioreactor, leads to low cell productivity despite high specific productivities of relevant metabolites. We hypothesized that high H(2)O(2) concentrations in the feed-zone led to local cell death, which in turn, lead to lower cell productivity. To test the hypothesis, a mathematical model was developed. Bacillus subtilis 168 was used as the model system in this study. The model simulations of cell concentrations in the bioreactor-zone were verified with the experimental results. The feed-zone H(2)O(2) concentrations remained 12-14 times higher than bulk bioreactor concentrations. The high local concentrations are expected to cause local cell killing, which explains the decrease in overall cell production by 50% at 300 rpm compared to conventional cultivation. Further, among the four different feed strategies studied using the model, dissolved oxygen (DO) controlled H(2)O(2) feed strategy caused least local cell killing and improved overall cell production by 34%.

  1. A Survey of Food Projects in the English NHS Regions and Health Action Zones in 2001

    ERIC Educational Resources Information Center

    Caraher, Martin; Cowburn, Gill

    2004-01-01

    Background and Objective: This article sets out the findings from an analysis of food projects, with a particular emphasis on fruit and vegetables, from the 26 Health Action Zones (HAZs) in England and those taking place within the former NHS regional areas in 2001. The objective was to gather information on the existing practice to inform future…

  2. Enhancing international earth science competence in natural hazards through 'geoNatHaz

    NASA Astrophysics Data System (ADS)

    Giardino, Marco; Clague, John J.

    2010-05-01

    "geoNatHaz" is a Transatlantic Exchange Partnership project (TEP 2009-2012) within the framework of the EU-Canada programme for co-operation in higher education, training, and youth. The project is structured to improve knowledge and skills required to assess and manage natural hazards in mountain regions. It provides student exchanges between European and Canadian universities in order to enhance international competence in natural hazard research. The university consortium is led by Simon Fraser University (Canada) and Università degli studi di Torino (Italy). Partner universities include the University of British Columbia, Queen's University, Università di Bologna, Université de Savoie, and the University of Athens. Université de Lausanne (Switzerland) supports the geoNatHaz advisory board through its bilateral agreements with Canadian partner universities. The geoNatHaz project promotes cross-cultural understanding and internationalization of university natural hazard curricula through common lectures, laboratory exercises, and field activities. Forty graduate students from the seven Canadian and European partner universities will benefit from the project between 2009 and 2012. Some students enrolled in graduate-level earth science and geologic engineering programs spend up to five months at the partner universities, taking courses and participating in research teams under the direction of project scientists. Other students engage in short-term (four-week) exchanges involving training in classic natural hazard case-studies in mountain regions of Canada and Europe. Joint courses are delivered in English, but complementary cultural activities are offered in the languages of the host countries. Supporting organizations offer internships and technical and scientific support. Students benefit from work-study programs with industry partners. Supporting organizations include government departments and agencies (Geological Survey of Canada; CNR-IRPI National

  3. Absence of functional active zone protein Bassoon affects assembly and transport of ribbon precursors during early steps of photoreceptor synaptogenesis.

    PubMed

    Regus-Leidig, Hanna; tom Dieck, Susanne; Brandstätter, Johann Helmut

    2010-06-01

    The retinal photoreceptor ribbon synapse is a structurally and functionally unique type of chemical synapse, specialized for tonic release of neurotransmitter in the dark. It is characterized by the presynaptic ribbon, an electron-dense organelle at the active zone, which is covered by hundreds of synaptic vesicles. Recently we showed that photoreceptor ribbon complexes are assembled from non-membranous, spherical densities--the precursor spheres--during the first two postnatal weeks of photoreceptor synaptogenesis. A core component of the precursor spheres and a key player in attaching the ribbon to the active zone is the presynaptic cytomatrix protein Bassoon. In this study, we examined in a comprehensive light and electron microscopic analysis whether Bassoon plays a role in the formation of the precursor spheres using Bassoon mutant mice lacking functional Bassoon. We report that developing Bassoon mutant photoreceptors contain fewer and smaller precursor spheres and that transport of precursor spheres to nascent synapses is delayed compared to wild-type controls. Moreover, western blot analyses of homogenates from postnatal day 0 (P0) to P14 Bassoon mutant retinae exhibit lower RIBEYE and Piccolo protein levels compared to the wild type, indicating elevated protein degradation in the absence of Bassoon. Our findings reveal a novel function of Bassoon in the early formation and delivery of precursor spheres to nascent ribbon synaptic sites in addition to its known role in ribbon anchoring during later stages of photoreceptor ribbon synaptogenesis.

  4. Study of Reservoir Heterogencities and Structural Features Affecting Production in the Shallow Oil Zone, Eastern Elk Hills Area, California

    SciTech Connect

    Janice Gillespie

    2004-11-01

    Late Neogene (Plio-Pleistocene) shallow marine strata of the western Bakersfield Arch and Elk Hills produce hydrocarbons from several different reservoirs. This project focuses on the shallow marine deposits of the Gusher and Calitroleum reservoirs in the Lower Shallow Oil Zone (LSOZ). In the eastern part of the study area on the Bakersfield Arch at North and South Coles Levee field and in two wells in easternmost Elk Hills, the LSOZ reservoirs produce dry (predominantly methane) gas. In structurally higher locations in western Elk Hills, the LSOZ produces oil and associated gas. Gas analyses show that gas from the eastern LSOZ is bacterial and formed in place in the reservoirs, whereas gas associated with oil in the western part of the study area is thermogenic and migrated into the sands from deeper in the basin. Regional mapping shows that the gas-bearing LSOZ sands in the Coles Levee and easternmost Elk Hills area are sourced from the Sierra Nevada to the east whereas the oil-bearing sands in western Elk Hills appear to be sourced from the west. The eastern Elk Hills area occupied the basin depocenter, farthest from either source area. As a result, it collected mainly low-permeability offshore shale deposits. This sand-poor depocenter provides an effective barrier to the updip migration of gases from east to west. The role of small, listric normal faults as migration barriers is more ambiguous. Because our gas analyses show that the gas in the eastern LSOZ reservoirs is bacterial, it likely formed in-place near the reservoirs and did not have to migrate far. Therefore, the gas could have been generated after faulting and accumulated within the fault blocks as localized pools. However, bacterial gas is present in both the eastern AND western parts of Elk Hills in the Dry Gas Zone (DGZ) near the top of the stratigraphic section even though the measured fault displacement is greatest in this zone. Bacterial gas is not present in the west in the deeper LSOZ which

  5. Distribution of polychlorinated biphenyls in an urban riparian zone affected by wastewater treatment plant effluent and the transfer to terrestrial compartment by invertebrates.

    PubMed

    Yu, Junchao; Wang, Thanh; Han, Shanlong; Wang, Pu; Zhang, Qinghua; Jiang, Guibin

    2013-10-01

    In this study, we investigated the distribution of polychlorinated biphenyls (PCBs) in a riparian zone affected by the effluent from a wastewater treatment plant (WWTP). River water, sediment, aquatic invertebrates and samples from the surrounding terrestrial compartment such as soil, reed plants and several land based invertebrates were collected. A relatively narrow range of δ(13)C values was found among most invertebrates (except butterflies, grasshoppers), indicating a similar energy source. The highest concentration of total PCBs was observed in zooplankton (151.1 ng/g lipid weight), and soil dwelling invertebrates showed higher concentrations than phytophagous insects at the riparian zone. The endobenthic oligochaete Tubifex tubifex (54.28 ng/g lw) might be a useful bioindicator of WWTP derived PCBs contamination. High bioaccumulation factors (BAFs) were observed in collected aquatic invertebrates, although the biota-sediment/soil accumulation factors (BSAF) remained relatively low. Emerging aquatic insects such as chironomids could carry waterborne PCBs to the terrestrial compartment via their lifecycles. The estimated annual flux of PCBs for chironomids ranged from 0.66 to 265 ng⋅m(-2)⋅y(-1). Although a high prevalence of PCB-11 and PCB-28 was found for most aquatic based samples in this riparian zone, the mid-chlorinated congeners (e.g. PCB-153 and PCB-138) became predominant among chironomids and dragonflies as well as soil dwelling invertebrates, which might suggest a selective biodriven transfer of different PCB congeners.

  6. Mineralogical constraint for metamorphic conditions in a shear zone affecting the Archean Ngoulemakong tonalite, Congo craton (Southern Cameroon) and retentivity of U-Pb SHRIMP zircon dates

    NASA Astrophysics Data System (ADS)

    Tchameni, R.; Lerouge, C.; Penaye, J.; Cocherie, A.; Milesi, J. P.; Toteu, S. F.; Nsifa, N. E.

    2010-08-01

    In the Ngoulemakong region of the Ntem unit (South Cameroon), tonalite crops out as intrusions of various sizes cross-cutting the charnockite suite. Both of these granitoids are affected by NE-SW and WNW-ESE sinistral and dextral shear zones. Tonalite in the WNW-ESE shear zone are deformed and shows metamorphic assemblages represented by quartz-microcline-biotite-garnet-plagioclase-scapolite-fluoro-apatite and chlorite-sulfides-epidote-muscovite-quartz-calcite not recorded by the undeformed rocks outside it. These mineralogical assemblages provide evidence of decreasing pressure-temperature conditions from granulite-amphibolite-facies in the moderate deformed part to greenschist-facies in the central part of the shear plane. The higher fluid (H 2O, CO 2, S, F, Cl, K, and Na) activities and high-grade recrystallizations recorded in the shear zone favour a Pb loss hypothesis in the zircons. U-Pb SHRIMP zircon dating yield an emplacement age of 2865 ± 4 Ma for the tonalite but does not permit the determination of the age of the high-grade event responsible for the Pb loss. These results provide evidence of the retentivity of U-Pb zircon dates under high grade conditions.

  7. Morphological and mechanical characterization of the acid-base resistant zone at the adhesive-dentin interface of intact and caries-affected dentin.

    PubMed

    Inoue, Go; Tsuchiya, Satoko; Nikaido, Toru; Foxton, Richard M; Tagami, Junji

    2006-01-01

    This study examined the ultrastructure of both intact and caries affected dentin-adhesive interface after artificial secondary caries formation, using scanning electron microscopy and nanoindentation testing. Half of the prepared specimens were bonded with Clearfil SE Bond (Kuraray Medical, Japan) and a resin composite (Metafil Flo, Sun Medical, Japan) for the nanoindentation test. The other specimens were stored in a buffered demineralizing solution for 90 minutes, then observed using SEM. An acid-base resistant zone (ABRZ) was observed beneath the hybrid layer, distinguished by argon-ion etching. The ABRZ of caries-affected dentin was thicker than that of normal dentin, while its nanohardess was lower than normal dentin (p<0.05). It is suggested that the monomer of Clearfil SE Bond penetrated deeper than previously reported, creating a so-called "hybrid layer." However, its physical properties depended on the condition of the dentin.

  8. Living in the heart of a volcanic hazard zone and the issues that affect community vulnerability and resilience

    NASA Astrophysics Data System (ADS)

    Bird, Deanne; Gísladóttir, Guőrún; Dominey-Howes, Dale

    2010-05-01

    Volcanic risk mitigation strategies were revised for residents living in the eastern jökulhlaup hazard zone of Mýrdalsjökull, southern Iceland. These plans were trialled during a full-scale evacuation exercise on 25 March 2006. In order to assess residents' perception of and response to the exercise and proposed mitigation strategies a mixed methods survey was applied. This investigation consisted of field observations during the exercise and semi-structured interviews with emergency management officials and residents of a small rural community after the exercise. This community was the focus of this survey because these residents did not consider the previous plan appropriate to their beliefs and needs. The results of the survey revealed that residents are reluctant to evacuate and do not agree with the proposed strategies. Residents believe that the newly devised plans do not address the contextual issues of their community. Factors influencing the residents' perception are inherited knowledge, attachment to place and livelihood connections (i.e. concern for livestock). Residents' requests for alternative plans, in case adverse environmental conditions prevent evacuation, were ignored. Consequently, emergency managers failed to resolve residents' risk mitigation concerns prior to the evacuation exercise. We recommend that emergency managers should incorporate local knowledge and perceptions to ensure reduced vulnerability and enhanced community resilience.

  9. Surface Features Analysis in Salt-Affected Area Using Hyperspectral Data: A Case Study in the Zone of Chotts, Tunisia

    NASA Astrophysics Data System (ADS)

    Bouaziz, Moncef; Liesenberg, Veraldo; Bouaziz, Samir; Gloaguen, Richard

    2010-12-01

    Arid and semi-arid regions are most affected by Salinity. Chotts regions in southern Tunisia are such an area, where the excessive content of salt in the soil is a hard faced problem. Soil salinity in this area enforces several environmental problems such as limiting plant growth, reducing crop productivity, degrading soil quality and leads to accelerated rates rill and gully erosion . Remote sensing analysis by the mean of spectral analysis, geomorphologic aspect from digital elevation models and distribution of rainfall intensity from satellite data are used in this study to discern features and patterns of areas affected by salt. Correlation between these remote sensing indicators is made in order to assess the contribution of each indicator to identify the salt-affected area. The approach followed in this study was applied on Hyperspectral data from EO-1 Mission. Hyperion data are promoted due to their very high spectral resolution and wide enhanced spatial information. The present study highlighted the high correlation between the flat surfaces and the high content of salt in the soil (from soil salinity indices) on one hand and a low correlation between the high intensity of rainfall distribution and indicators of low salt content in the soil on the other hand.

  10. Differences in Water Vapor Radiative Transfer among 1D Models Can Significantly Affect the Inner Edge of the Habitable Zone

    NASA Astrophysics Data System (ADS)

    Yang, Jun; Leconte, Jérémy; Wolf, Eric T.; Goldblatt, Colin; Feldl, Nicole; Merlis, Timothy; Wang, Yuwei; Koll, Daniel D. B.; Ding, Feng; Forget, François; Abbot, Dorian S.

    2016-08-01

    An accurate estimate of the inner edge of the habitable zone is critical for determining which exoplanets are potentially habitable and for designing future telescopes to observe them. Here, we explore differences in estimating the inner edge among seven one-dimensional radiative transfer models: two line-by-line codes (SMART and LBLRTM) as well as five band codes (CAM3, CAM4_Wolf, LMDG, SBDART, and AM2) that are currently being used in global climate models. We compare radiative fluxes and spectra in clear-sky conditions around G and M stars, with fixed moist adiabatic profiles for surface temperatures from 250 to 360 K. We find that divergences among the models arise mainly from large uncertainties in water vapor absorption in the window region (10 μm) and in the region between 0.2 and 1.5 μm. Differences in outgoing longwave radiation increase with surface temperature and reach 10-20 W m-2 differences in shortwave reach up to 60 W m-2, especially at the surface and in the troposphere, and are larger for an M-dwarf spectrum than a solar spectrum. Differences between the two line-by-line models are significant, although smaller than among the band models. Our results imply that the uncertainty in estimating the insolation threshold of the inner edge (the runaway greenhouse limit) due only to clear-sky radiative transfer is ≈10% of modern Earth’s solar constant (i.e., ≈34 W m-2 in global mean) among band models and ≈3% between the two line-by-line models. These comparisons show that future work is needed that focuses on improving water vapor absorption coefficients in both shortwave and longwave, as well as on increasing the resolution of stellar spectra in broadband models.

  11. Differences in Water Vapor Radiative Transfer among 1D Models Can Significantly Affect the Inner Edge of the Habitable Zone

    NASA Astrophysics Data System (ADS)

    Yang, Jun; Leconte, Jérémy; Wolf, Eric T.; Goldblatt, Colin; Feldl, Nicole; Merlis, Timothy; Wang, Yuwei; Koll, Daniel D. B.; Ding, Feng; Forget, François; Abbot, Dorian S.

    2016-08-01

    An accurate estimate of the inner edge of the habitable zone is critical for determining which exoplanets are potentially habitable and for designing future telescopes to observe them. Here, we explore differences in estimating the inner edge among seven one-dimensional radiative transfer models: two line-by-line codes (SMART and LBLRTM) as well as five band codes (CAM3, CAM4_Wolf, LMDG, SBDART, and AM2) that are currently being used in global climate models. We compare radiative fluxes and spectra in clear-sky conditions around G and M stars, with fixed moist adiabatic profiles for surface temperatures from 250 to 360 K. We find that divergences among the models arise mainly from large uncertainties in water vapor absorption in the window region (10 μm) and in the region between 0.2 and 1.5 μm. Differences in outgoing longwave radiation increase with surface temperature and reach 10–20 W m‑2 differences in shortwave reach up to 60 W m‑2, especially at the surface and in the troposphere, and are larger for an M-dwarf spectrum than a solar spectrum. Differences between the two line-by-line models are significant, although smaller than among the band models. Our results imply that the uncertainty in estimating the insolation threshold of the inner edge (the runaway greenhouse limit) due only to clear-sky radiative transfer is ≈10% of modern Earth’s solar constant (i.e., ≈34 W m‑2 in global mean) among band models and ≈3% between the two line-by-line models. These comparisons show that future work is needed that focuses on improving water vapor absorption coefficients in both shortwave and longwave, as well as on increasing the resolution of stellar spectra in broadband models.

  12. Why person affected by leprosy did not look after their plantar ulcer? Experience from Pakokku zone, Myanmar.

    PubMed

    Win, Le Le; Shwe, San; Maw, Win; Ishida, Yutaka; Myint, Kyaw; Mar, Kyi Kyi; Min, Thandar; Oo, Phyo Min; Khine, Aye Win

    2010-09-01

    A cross-sectional study was carried out to identify methods of caring plantar ulcers in leprosy patients and the underlying causes of poor plantar ulcer care during January and February 2008. This was conducted in Pakokku zone as it was one of the "9 selected townships of the Disabilities survey, i.e., Basic Health Staff project 2003/4", which was funded by Japan International Cooperation Agency. After getting consent, all available leprosy cases, i.e., 101 cases with foot disability grade 2 were interviewed with the pre-tested questionnaire. Among 101 cases, 13 cases who took care of their ulcer poorly and 20 who did none of the recommended measures were recruited for in-depth interview (IDI). The subjects were largely old people, males and people with no marriage partner. The majority had earned money by doing sedentary job. Prolongation of ulcers was observed in 78 cases. Most had been suffering from ulcers for years. When asking face-to-face interview, all the recommended care measures were not reported. Among these recommended measures, a large number of respondents reported about soaking measure. However, these reported measures were contradicted to the preventive methods which they disclosed in IDI. Plantar ulcer care seemed to be an individualised practice. The individual ways of performing were related to their view of ulcer, the environment, and occupation, and custom, communication with family and health staff. The findings identified the actual practice of plantar ulcer care in study areas. It is suggested that the current performance of planar ulcer care is inadequate and more attention should be given to achieve the target set by the programme as a recommendation. PMID:20857653

  13. Natural Radiation for Identification and Evaluation of Risk Zones for Affectation of Activated Faults in Aquifer Overexploited.

    NASA Astrophysics Data System (ADS)

    Ramos-Leal, J.; Lopez-Loera, H.; Carbajal-Perez, N.

    2007-05-01

    In basins as Mexico, Michoacán, Guanajuato, Queretaro, Aguascalientes and San Luis Potosi, the existence of faults and fractures have affected the urban infrastructure, lines of conduction of drinkable water, pipelines, etc., that when not being identified and considered, they don't reflect the real impact that these cause also to the aquifer system, modifying the permeability of the means and in occasions they work as preferential conduits that communicate hydraulically potentially to the aquifer with substances pollutants (metals, fertilizers, hydrocarbons, waste waters, etc.) located in the surface. In the Valley of San Luis Potosi, Villa of Reyes, Arista, Ahualulco and recently The Huizache-Matehuala is being strongly affected by faulting and supposedly due cracking to subsidence, however, the regional tectonic could also be the origin of this phenomenon. To know the origin of the faults and affectation to the vulnerability of the aquifer few works they have been carried out in the area. A preliminary analysis indicates that it is possible that a tectonic component is affecting the area and that the vulnerability of the aquifer in that area you this increasing. Before such a situation, it is necessary to carry out the isotopic study of the same one, for this way to know among other things, isotopic characterization, recharge places and addresses of flow of the groundwater; quality of waters and the behavior hydrochemistry with relationship to the faults. High radon values were measured in San Luis Potosi Valley, the natural source of radon could be the riolites and however, these are located to almost a once thousand meters deep for what the migration of the gas is not very probable. The anomalies radiometrics was not correlation with the faults in this case. In some areas like the Valley of Celaya, the origin of the structures and the tectonic activity in the area was confirmed, identifying the structural arrangement of the faulting, the space relationships

  14. Weld solidification and HAZ liquation in a metastable-beta titanium alloy-Beta-21S. [Ti-15wt%Mo-2. 7wt%Nb-3wt%Al-0. 2wt%Si

    SciTech Connect

    Baeslack, W.A. III; Liu, P.S. ); Paskell, T. )

    1993-03-01

    Beta-21S is a new, metastable-beta titanium alloy which exhibits excellent oxidation resistance and mechanical properties at elevated temperatures. From a weld solidification standpoint, this alloy chemistry is of particular interest because its major beta-stabilizing elements (Mo and Nb) both exhibit equilibrium partitioning ratios (k[sub o]) greater than unity, indicating their simultaneous partitioning during weld solidification to the initial solid to form (i.e., dendrite cores), and correspondingly their depletion in the final regions of solidification (i.e., dendrite interstices). Such elemental partitioning, if retained down to room temperature, may be expected to promote local variations in the postweld aging response. The objectives of the present investigation were to characterize Gas Tungsten-Arc weld solidification and HAZ liquation phenomena in Beta-21S and to examine the influence of residual microsegregation in the weld zone on alpha precipitation during postweld heat treatment.

  15. How do changes in the Diurnal Cycle affect Bi-stability and Climate Sensitivity in the Habitable Zone?

    NASA Astrophysics Data System (ADS)

    Boschi, R.; Valerio, L.

    2013-09-01

    fundamental properties of planets in the habitable zone from relatively simple observables.

  16. The longevity of lava dome eruptions: analysis of the global DomeHaz database

    NASA Astrophysics Data System (ADS)

    Ogburn, S. E.; Wolpert, R.; Calder, E.; Pallister, J. S.; Wright, H. M. N.

    2015-12-01

    The likely duration of ongoing volcanic eruptions is a topic of great interest to volcanologists, volcano observatories, and communities near volcanoes. Lava dome forming eruptions can last from days to centuries, and can produce violent, difficult-to-forecast activity including vulcanian to plinian explosions and pyroclastic density currents. Periods of active dome extrusion are often interspersed with periods of relative quiescence, during which extrusion may slow or pause altogether, but persistent volcanic unrest continues. This contribution focuses on the durations of these longer-term unrest phases, hereafter eruptions, that include periods of both lava extrusion and quiescence. A new database of lava dome eruptions, DomeHaz, provides characteristics of 228 eruptions at 127 volcanoes; for which 177 have duration information. We find that while 78% of dome-forming eruptions do not continue for more than 5 years, the remainder can be very long-lived. The probability distributions of eruption durations are shown to be heavy-tailed and vary by magma composition. For this reason, eruption durations are modeled with generalized Pareto distributions whose governing parameters depend on each volcano's composition and eruption duration to date. Bayesian predictive distributions and associated uncertainties are presented for the remaining duration of ongoing eruptions of specified composition and duration to date. Forecasts of such natural events will always have large uncertainties, but the ability to quantify such uncertainty is key to effective communication with stakeholders and to mitigation of hazards. Projections are made for the remaining eruption durations of ongoing eruptions, including those at Soufrière Hills Volcano, Montserrat and Sinabung, Indonesia. This work provides a quantitative, transferable method and rationale on which to base long-term planning decisions for dome forming volcanoes of different compositions, regardless of the quality of an

  17. Towards flash flood disaster prevention: the SciNetNat Haz proposal

    NASA Astrophysics Data System (ADS)

    Konstantinos, Papatheodorou; Elena, Tzanou; Carmen, Maftei; Ozgur, Kirca; Hafzullah, Aksoy

    2015-04-01

    Floods occur with a continuously increasing frequency due to climatic changes and cause serious damage in the wider Black Sea area, endangering human life and property. As societies continuously expand, these phenomena are expected to play an increasingly important role, blocking sustainable development unless properly tackled. Flash flood prevention seems at this point, to be the target of effectively mitigating the potential threat. Since in many cases, there is a cross-border character of the problem, collaborative efforts have to be made involving cooperation between countries. To this end, a variety of problems exist, including the "information gap" related to the unavailability of data and the multitude of methodologies used to assess flood hazard; a fact that renders comparison of hazard assessment results and cross border cooperation ineffective. An effort made within the context of the SciNetNatHaz project, suggests a two step approach to produce reliable the results which can lead to decision making regarding designing preventive measures. The first step aims at defining the flood prone areas on a regional scale, using geomorphometric models and readily available topographic data; thus overcoming the problem of data availability for any region of interest. The second step follows a vulnerability and risk assessment of the flood prone areas of interest and focuses on the calculation of flood parameters on a local scale using hydraulic models. Implementation of the full process is based on Open Source software tools so that it can be implemented with minimal costs by anyone interested. Implementation of the proposed procedure in three different cases in Greece and in Romania shows that it can provide accurate and reliable results to support decision making regarding the design of preventive measures. Keywords: Flash floods, hazard assessment, flood disaster prevention, HEC-RAS, SAGA GIS . Acknowledgements: This work is partially funded by the EU through the

  18. Design requirements for ERD in diffusion-dominated media: how do injection interval, bioactive zones and reaction kinetics affect remediation performance?

    NASA Astrophysics Data System (ADS)

    Chambon, J.; Lemming, G.; Manoli, G.; Broholm, M. M.; Bjerg, P.; Binning, P. J.

    2011-12-01

    Enhanced Reductive Dechlorination (ERD) has been successfully used in high permeability media, such as sand aquifers, and is considered to be a promising technology for low permeability settings. Pilot and full-scale applications of ERD at several sites in Denmark have shown that the main challenge is to get contact between the injected bacteria and electron donor and the contaminants trapped in the low-permeability matrix. Sampling of intact cores from the low-permeability matrix has shown that the bioactive zones (where degradation occurs) are limited in the matrix, due to the slow diffusion transport processes, and this affects the timeframes for the remediation. Due to the limited ERD applications and the complex transport and reactive processes occurring in low-permeability media, design guidelines are currently not available for ERD in such settings, and remediation performance assessments are limited. The objective of this study is to combine existing knowledge from several sites with numerical modeling to assess the effect of the injection interval, development of bioactive zones and reaction kinetics on the remediation efficiency for ERD in diffusion-dominated media. A numerical model is developed to simulate ERD at a contaminated site, where the source area (mainly TCE) is located in a clayey till with fractures and interbedded sand lenses. Such contaminated sites are common in North America and Europe. Hydro-geological characterization provided information on geological heterogeneities and hydraulic parameters, which are relevant for clay till sites in general. The numerical model couples flow and transport in the fracture network and low-permeability matrix. Sequential degradation of TCE to ethene is modeled using Monod kinetics, and the kinetic parameters are obtained from laboratory experiments. The influence of the reaction kinetics on remediation efficiency is assessed by varying the biomass concentration of the specific degraders. The injected

  19. Hydrogeologic factors that affect the flowpath of water in selected zones of the Edwards Aquifer, San Antonio region, Texas

    USGS Publications Warehouse

    Groschen, G.E.

    1996-01-01

    The Edwards aquifer in the San Antonio region supplies drinking water for more than 1 million people. Proper development and protection of the aquifer is a high priority for local and State authorities. To better understand the flow of water in two major flowpaths in the Edwards aquifer, stratigraphic, structural, hydrologic, and geochemical data were analyzed. The western Medina flowpath is in parts of Uvalde, Medina, and Bexar Counties, and the eastern flowpath is in northern Bexar and central Comal Counties. A major hydrogeologic factor that affects the pattern of flow in the Edwards aquifer is the spatial and temporal distribution of recharge. Other hydrogeologic factors that affect flowpaths include internal boundaries and the location and rate of spring discharge. The relative displacement of faults and the high permeability layers have substantial control on the discharge at springs and on the flowpaths in the Edwards aquifer. Analysis of the estimated recharge to the Edwards aquifer during 1982 89 indicated that during years of substantial precipitation, a large part of the net recharge probably is diffuse infiltration of precipitation over large parts of the recharge area. During years with below-normal precipitation, most recharge is leakage from rivers and streams that drain the catchment subbasins. In the western Medina flowpath, concentrations of major ions indicate saturation of calcite and undersaturation of dolomite the two minerals that constitute most of the Edwards aquifer matrix. Concentrations of dissolved calcium, alkalinity, and dissolved chloride in the eastern flowpath are greater than those in the western Medina flowpath. These upward trends in concentrations might result in part from: (1) increased development in the recharge area, (2) mineralized effluent from developed areas, or (3) increased dissolution of aquifer material. Tritium data from wells sampled in and near the western Medina flowpath indicate no vertical stratification of

  20. Factors Affecting Utilization of Maternal Health Care Services in Kombolcha District, Eastern Hararghe Zone, Oromia Regional State, Eastern Ethiopia.

    PubMed

    Zelalem Ayele, Desalew; Belayihun, Bekele; Teji, Kedir; Admassu Ayana, Desalegn

    2014-01-01

    Introduction. World health organization estimates that more than half a million women lose their lives in the process of reproduction worldwide every year and most of these mortalities are avoidable if mothers have access to maternal health care services. Objectives. This study was conducted with objectives of determining the prevalence of utilization of maternal health care services and identifying factors affecting it. Methodology. A community based cross-sectional survey was conducted in six kebeles of Kombolcha district. A total of 495 women of reproductive age participated in the study and their selection was made using simple random sampling technique and data was collected using an interviewer-administered structured questionnaire. The data was analyzed using SPSS version 16. Results. A total of 495 women were included in this study and from these women about 86.1% had at least one ANC visit during their last pregnancy. About 61.7% of mothers had less than four visits which is less than the recommended and 46.2% started it in the second trimester. Only 25.3% of respondents gave birth in health institutions and rural women were less likely to use institutional delivery 20.9% compared to urban women 35.9%. Recommendations. More efforts should be given to educate society in general and mothers in particular, to strengthen community participation and to increase the accessibility of maternal health care services. Moreover, providing accurate information about the services provided in the health institutions is required from the concerned governmental and nongovernmental organizations.

  1. M3B2 and M5B3 Formation in Diffusion-Affected Zone During Transient Liquid Phase Bonding Single-Crystal Superalloys

    NASA Astrophysics Data System (ADS)

    Sheng, Naicheng; Hu, Xiaobing; Liu, Jide; Jin, Tao; Sun, Xiaofeng; Hu, Zhuangqi

    2015-04-01

    Precipitates in the diffusion-affected zone (DAZ) during transient liquid phase bonding (TLP) single-crystal superalloys were observed and investigated. Small size and dendritic-shaped precipitates were identified to be M3B2 borides and intergrowth of M3B2/M5B3 borides. The orientation relationships among M3B2, M5B3, and matrix were determined using transmission electron microscope (TEM). Composition characteristics of these borides were also analyzed by TEM energy-dispersive spectrometer. Because this precipitating phenomenon deviates from the traditional parabolic transient liquid phase bonding model which assumed a precipitates free DAZ during TLP bonding, some correlations between the deviation of the isothermal solidification kinetics and these newly observed precipitating behaviors were discussed and rationalized when bonding the interlayer containing the high diffusivity melting point depressant elements and substrates of low solubility.

  2. The Use of Haz-Flote to Efficiently Remove Mercury from Contaminated Materials

    SciTech Connect

    Terry Brown

    2009-03-03

    There are thousands of known contaminated sites in the United Stated, including Superfund sites (1500 to 2100 sites), RCRA corrective action sites (1500 to 3500 sites), underground storage tanks (295,000 sites), U.S. Department of Defense sites (7300 sites), U.S. Department of Energy sites (4,000 sites), mining refuse piles, and numerous other hazardous metals and organic contamination sites. Only a small percentage of these sites has been cleaned up. The development of innovative technologies to handle the various clean-up problems on a national and international scale is commonplace. Many innovative technologies have been developed that can be used to effectively remediate contaminated materials. Unfortunately, many of these technologies are only effective for materials coarser than approximately 200 mesh. In addition, these technologies usually require considerable investment in equipment, and the clean-up costs of soil material are relatively high - in excess of $100 to $500 per yd{sup 3}. These costs result from the elaborate nature of the processes, the costs for power, and the chemical cost. The fine materials are disposed of or treated at considerable costs. As a result, the costs often associated with amelioration of contaminated sites are high. Western Research institute is in the process of developing an innovative soil washing technology that addresses the removal of contaminants from the fine size-fraction materials located at many of the contaminated sites. This technology has numerous advantages over the other ex-situ soil washing techniques. It requires a low capital investment, low operating costs and results in high levels of re-emplacement of the cleaned material on site. The process has the capability to clean the fine fraction (<200 mesh) of the soil resulting in a replacement of 95+% of the material back on-side, reducing the costs of disposal. The Haz-Flote{trademark} technology would expand the application of soil washing technology to heavy

  3. Inclusions and Microstructure of Ce-Added Weld Metal Coarse Grain Heat-Affected Zone in Twin-Wire Submerged-Arc Welding

    NASA Astrophysics Data System (ADS)

    Yu, S. F.; Yan, N.; Chen, Y.

    2016-06-01

    In high heat-input multi-pass twin-wire submerged-arc welding, weld metal of previous pass will be affected by the heat input of subsequent one and form coarse-grained heat-affected zone (CGHAZ). This study focused on the effects of welding thermal cycle on the inclusions and microstructure of Ce-alloyed weld metal CGHAZ. According to the study of inclusions and microstructure of weld metal CGHAZ, it was found that the composition and type of the inclusions did not change under the effect of welding thermal cycle. Although the inclusions were coarsened slightly, the promoting ability to acicular ferrite (AF) was not deprived after thermal cycling. There are three types of AF in weld metal CGHAZ, which include oxy-sulfides of Ce inclusions-promoted AF, home-position-precipitated AF, and sympathetic AF. Results showed more than 80% of microstructure was AF, which greatly benefited the mechanical properties of weld metal CGHAZ, even though granular bainite and M-A constituents were generated.

  4. Evidence of multi-stage faulting by clay mineral analysis: Example in a normal fault zone affecting arkosic sandstones (Annot sandstones)

    NASA Astrophysics Data System (ADS)

    Buatier, Martine D.; Cavailhes, Thibault; Charpentier, Delphine; Lerat, Jérémy; Sizun, Jean Pierre; Labaume, Pierre; Gout, Claude

    2015-06-01

    Fault affecting silicoclastic sediments are commonly enriched in clay minerals. Clays are sensitive to fluid-rock interactions and deformation mechanisms; in this paper, they are used as proxy for fault activity and behavior. The present study focuses on clay mineral assemblages from the Point Vert normal fault zone located in the Annot sandstones, a Priabonian-Rupelian turbidite succession of the Alpine foredeep in SE France. In this area, the Annot sandstones were buried around 6-8 km below the front of Alpine nappes soon after their deposition and exhumed during the middle-late Miocene. The fault affects arkosic sandstone beds alternating with pelitic layers, and displays throw of about thirty meters. The fault core zone comprises intensely foliated sandstones bounding a corridor of gouge about 20 cm thick. The foliated sandstones display clay concentration along S-C structures characterized by dissolution of K-feldspar and their replacement by mica, associated with quartz pressure solution, intense microfracturation and quartz vein precipitation. The gouge is formed by a clayey matrix containing fragments of foliated sandstones and pelites. However, a detailed petrographical investigation suggests complex polyphase deformation processes. Optical and SEM observations show that the clay minerals fraction of all studied rocks (pelites and sandstones from the damage and core zones of the fault) is dominated by white micas and chlorite. These minerals have two different origins: detrital and newly-formed. Detrital micas are identified by their larger shape and their chemical composition with a lower Fe-Mg content than the newly-formed white micas. In the foliated sandstones, newly-formed white micas are concentrated along S-C structures or replace K-feldspar. Both types of newly formed micas display the same chemical composition confirmed microstructural observations suggesting that they formed in the same conditions. They have the following structural formulas: Na0

  5. Will changes in root-zone temperature in boreal spring affect recovery of photosynthesis in Picea mariana and Populus tremuloides in a future climate?

    PubMed

    Fréchette, Emmanuelle; Ensminger, Ingo; Bergeron, Yves; Gessler, Arthur; Berninger, Frank

    2011-11-01

    Future climate will alter the soil cover of mosses and snow depths in the boreal forests of eastern Canada. In field manipulation experiments, we assessed the effects of varying moss and snow depths on the physiology of black spruce (Picea -mariana (Mill.) B.S.P.) and trembling aspen (Populus tremuloides Michx.) in the boreal black spruce forest of western Québec. For 1 year, naturally regenerated 10-year-old spruce and aspen were grown with one of the following treatments: additional N fertilization, addition of sphagnum moss cover, removal of mosses, delayed soil thawing through snow and hay addition, or accelerated soil thawing through springtime snow removal. Treatments that involved the addition of insulating moss or snow in the spring caused lower soil temperature, while removing moss and snow in the spring caused elevated soil temperature and thus had a warming effect. Soil warming treatments were associated with greater temperature variability. Additional soil cover, whether moss or snow, increased the rate of photosynthetic recovery in the spring. Moss and snow removal, on the other hand, had the opposite effect and lowered photosynthetic activity, especially in spruce. Maximal electron transport rate (ETR(max)) was, for spruce, 39.5% lower after moss removal than with moss addition, and 16.3% lower with accelerated thawing than with delayed thawing. Impaired photosynthetic recovery in the absence of insulating moss or snow covers was associated with lower foliar N concentrations. Both species were affected in that way, but trembling aspen generally reacted less strongly to all treatments. Our results indicate that a clear negative response of black spruce to changes in root-zone temperature should be anticipated in a future climate. Reduced moss cover and snow depth could adversely affect the photosynthetic capacities of black spruce, while having only minor effects on trembling aspen. PMID:22021010

  6. Will changes in root-zone temperature in boreal spring affect recovery of photosynthesis in Picea mariana and Populus tremuloides in a future climate?

    PubMed

    Fréchette, Emmanuelle; Ensminger, Ingo; Bergeron, Yves; Gessler, Arthur; Berninger, Frank

    2011-11-01

    Future climate will alter the soil cover of mosses and snow depths in the boreal forests of eastern Canada. In field manipulation experiments, we assessed the effects of varying moss and snow depths on the physiology of black spruce (Picea -mariana (Mill.) B.S.P.) and trembling aspen (Populus tremuloides Michx.) in the boreal black spruce forest of western Québec. For 1 year, naturally regenerated 10-year-old spruce and aspen were grown with one of the following treatments: additional N fertilization, addition of sphagnum moss cover, removal of mosses, delayed soil thawing through snow and hay addition, or accelerated soil thawing through springtime snow removal. Treatments that involved the addition of insulating moss or snow in the spring caused lower soil temperature, while removing moss and snow in the spring caused elevated soil temperature and thus had a warming effect. Soil warming treatments were associated with greater temperature variability. Additional soil cover, whether moss or snow, increased the rate of photosynthetic recovery in the spring. Moss and snow removal, on the other hand, had the opposite effect and lowered photosynthetic activity, especially in spruce. Maximal electron transport rate (ETR(max)) was, for spruce, 39.5% lower after moss removal than with moss addition, and 16.3% lower with accelerated thawing than with delayed thawing. Impaired photosynthetic recovery in the absence of insulating moss or snow covers was associated with lower foliar N concentrations. Both species were affected in that way, but trembling aspen generally reacted less strongly to all treatments. Our results indicate that a clear negative response of black spruce to changes in root-zone temperature should be anticipated in a future climate. Reduced moss cover and snow depth could adversely affect the photosynthetic capacities of black spruce, while having only minor effects on trembling aspen.

  7. Prediction and characterization of heat-affected zone formation in tin-bismuth alloys due to nickel-aluminum multilayer foil reaction

    SciTech Connect

    Hooper, R. J.; Davis, C. G.; Johns, P. M.; Adams, D. P.; Hirschfeld, D.; Nino, J. C.; Manuel, M. V.

    2015-06-26

    Reactive multilayer foils have the potential to be used as local high intensity heat sources for a variety of applications. In this study, most of the past research effort concerning these materials have focused on understanding the structure-property relationships of the foils that govern the energy released during a reaction. To improve the ability of researchers to more rapidly develop technologies based on reactive multilayer foils, a deeper and more predictive understanding of the relationship between the heat released from the foil and microstructural evolution in the neighboring materials is needed. This work describes the development of a numerical model for the purpose of predicting heat affected zone size in substrate materials. The model is experimentally validated using a commercially available Ni-Al multilayer foils and alloys from the Sn-Bi binary system. To accomplish this, phenomenological models for predicting the variation of physical properties (i.e., thermal conductivity, density, and heat capacity) with temperature and composition in the Sn-Bi system were utilized using literature data.

  8. Prediction and characterization of heat-affected zone formation in tin-bismuth alloys due to nickel-aluminum multilayer foil reaction

    DOE PAGES

    Hooper, R. J.; Davis, C. G.; Johns, P. M.; Adams, D. P.; Hirschfeld, D.; Nino, J. C.; Manuel, M. V.

    2015-06-26

    Reactive multilayer foils have the potential to be used as local high intensity heat sources for a variety of applications. In this study, most of the past research effort concerning these materials have focused on understanding the structure-property relationships of the foils that govern the energy released during a reaction. To improve the ability of researchers to more rapidly develop technologies based on reactive multilayer foils, a deeper and more predictive understanding of the relationship between the heat released from the foil and microstructural evolution in the neighboring materials is needed. This work describes the development of a numerical modelmore » for the purpose of predicting heat affected zone size in substrate materials. The model is experimentally validated using a commercially available Ni-Al multilayer foils and alloys from the Sn-Bi binary system. To accomplish this, phenomenological models for predicting the variation of physical properties (i.e., thermal conductivity, density, and heat capacity) with temperature and composition in the Sn-Bi system were utilized using literature data.« less

  9. The Stress-Relief Cracking Susceptibility of a New Ferritic Steel - Part I: Single-Pass Heat-Affected Zone Simulations

    SciTech Connect

    NAWROCKI,J.G.; DUPONT,J.N.; ROBINO,CHARLES V.; MARDER,A.R.

    1999-12-15

    The stress-relief cracking susceptibility of single-pass welds in a new ferritic steel, HCM2S, has been evaluated and compared to 2.25Cr-1Mo steel using Gleeble techniques. Simulated coarse-grained heat-affected zones (CGHAZ) were produced under a range of energy inputs and tested at various post-weld heat treatment (PWHT) temperatures. Both alloys were tested at a stress of 325 MPa. The 2.25 Cr-1Mo steel was also tested at 270 MPa to normalize for the difference in yield strength between the two materials. Light optical and scanning electron microscopy were used to characterize the CGHAZ microstructure. The ''as-welded'' CGHAZ of each alloy consisted of lath martensite or bainite and had approximately equal prior austenite grain sizes. The as-welded hardness of the 2.25Cr-1Mo steel CGHAZ was significantly higher than that of the HCM2S alloy. Over the range studied energy input had no effect on the as-welded microstructure or hardness of either alloy. The energy input also had no effect on the stress-relief cracking susceptibility of either material. Both alloys failed intergranularly along prior austenite grain boundaries under all test conditions. The 2.25Cr-1Mo steel samples experienced significant macroductility and some microductility when tested at 325 MPa. The ductility decreased significantly when tested at 270 MPa but was still higher that than of HCM2S at each test condition. The time to failure decreased with increasing PWHT Temperature for each material. There was no significant difference in the times to failure between the two materials. Varying energy input and stress had no effect on the time-to failure. The ductility, as measured by reduction in are% increased with increasing PWHT temperature for 2.25 Cr-1Mo steel tested at both stresses. However, PWHT temperature had no effect on the ductility of HCM2S. The hardness of the CGHAZ for 2.25Cr-1Mo steel decreased significantly after PWHT, but remained constant for HCM2S. The differences in stress

  10. Development of a priority list of chemical mixtures occurring at 1188 hazardous waste sites, using the HazDat database.

    PubMed

    Fay, R M; Mumtaz, M M

    1996-01-01

    Under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA or Superfund) section 104 mandate, as amended by the Superfund Amendments and Reauthorization Act (SARA) of 1986 USC 9604 (i)(2), the Agency for Toxic Substances and Disease Registry (ATSDR) is to identify individual substances and combinations of substances that pose the greatest public health hazard at hazardous waste sites. This has led to certain mandated activities of the Agency, including development of toxicological profiles, identification of data gaps, and, ultimately, establishment of a research agenda. The Agency has also developed HazDat, a database that captures pertinent information from public health assessments conducted at hazardous waste sites. As a preliminary step, data from sites have been analysed to identify the combinations of chemicals found in various environmental media. The most frequently found combinations were perchloroethylene (PERC) and trichloroethylene (TCE) in water (23.5% of sites); chromium (Cr) and lead (Pb) in soil (20.5%); benzene and toluene in air (3.5%); PERC, 1,1,1-trichloroethane (1,1,1-TCA) and TCE in water (11.6%); Cr, cadmium (Cd) and Pb in soil (12.0%); and benzene, PERC and TCE in air (2.2%). The findings of this analysis can be enhanced by factoring into the algorithm paramenters such as toxicity, source contribution, and likelihood of human exposure similar to that used for the Agency's priority list of 275 single substances. Assessment of the impact of chemical mixtures on human health is a formidable task, and estimating the toxicity of such mixtures, including the role of chemical interactions, is an equally demanding challenge. Because limited experimental data exist for chemical interactions, alternative methods such as predictive approaches and in vitro techniques are needed to address the many substances and their potential combinations. PMID:9119332

  11. Zones of Peace.

    ERIC Educational Resources Information Center

    Evans, Judith L.; And Others

    1996-01-01

    Children affected by armed violence face a specific set of stressors and challenges which calls for appropriate programming. This Coordinator's Notebook focuses on how to work with children affected by organized violence in order to provide them the best possible early childhood experiences. It is divided into five sections. "Children as Zones of…

  12. Physicochemical characteristics of the hyporheic zone affect redd site selection of chum salmon and fall chinook salmon in the Columbia River

    SciTech Connect

    Geist, David R. ); Hanrahan, Timothy P. ); Arntzen, Evan V. ); McMichael, Geoffrey A. ); Murray, Christopher J. ); Chien, Yi-Ju )

    2002-11-01

    Chum salmon Oncorhynchus keta and fall chinook salmon O. tshawytscha spawned at different locations in the vicinity of Ives Island, Washington, a side channel to the Columbia River downstream of Bonneville Dam. We hypothesized that measurements of water depth, substrate size, and water velocity alone would not explain the separation in spawning areas and began a 2-year investigation of physicochemical characteristics of the hyporheic zone. We found that chum salmon spawned in upwelling water that was significantly warmer than the surrounding river water. In contrast, fall chinook salmon constructed redds at downwelling sites where there was no difference in temperature between the river and its bed. Understanding the specific features that are important for chum salmon and fall chinook salmon redd site selection at Ives Island will be useful to resource managers attempting to maximize available spawning habitat for these species within the constraints imposed by other water resource needs.

  13. Haz-Map Glossary

    MedlinePlus

    ... a cumulative exposure with short latency, e.g., lead poisoning. Surfactant "A detergent compound that promotes lathering." [EPA] ... a cumulative exposure with short latency, e.g., lead poisoning. Surfactant "A detergent compound that promotes lathering." [EPA] ...

  14. Geochemical distribution of arsenic, cadmium, lead and zinc in river sediments affected by tailings in Zimapán, a historical polymetalic mining zone of México

    NASA Astrophysics Data System (ADS)

    Espinosa, Erik; Armienta, María Aurora; Cruz, Olivia; Aguayo, Alejandra; Ceniceros, Nora

    2009-10-01

    In the historical mining zone of Zimapán, México, unprotected tailings deposits are supplying contaminants to the local fluvial system. This research was conducted to assess the environmental hazard of these wastes and river sediments by determining the input, transport and seasonal variability of arsenic, cadmium, lead and zinc, and their speciation by an operationally defined scheme of decreasing lability: F1, fraction soluble in deionized water; F2, associated to carbonates; F3, oxides and hydroxides of iron; F4, sulfides and organic matter; F5, residual. Higher total concentrations of Cd, Pb and Zn were present in sediments in the dry season regarding the rainy season. In the dry season, As and Pb were principally associated with the more stable F3 and F5 fractions, whereas Cd was in F2 and F5, and Zn in F3, F2 and F5. In the rainy season the association was mainly F3 for As, while F2 and F3 contained most Cd, Pb and Zn. This fractionation indicates that the environmental hazard of Cd, Pb and Zn enhances upon a pH decrease due to their proportion in the carbonatic fraction, and shows a mobility increase during the rainy season.

  15. Bioturbation, geochemistry and geotechnics of sediments affected by the oxygen minimum zone on the Oman continental slope and abyssal plain, Arabian Sea

    NASA Astrophysics Data System (ADS)

    Meadows, Azra; Meadows, Peter S.; West, Fraser J. C.; Murray, John M. H.

    2000-01-01

    We investigate the way the oxygen minimum zone (OMZ) alters interactions between bioturbation and sediment geochemistry, and geotechnical properties. Sediments are compared within and below the OMZ on the Oman continental slope and adjacent abyssal plain during the post monsoonal autumn season. Quantitative measurements were made of Eh and pH, of total organic matter (TOM) and carbonate, of water content and shear strength, and of bioturbation structures in vertical profiles of subcores taken from spade-box core samples. The OMZ stations had distinctively low redox conditions and high carbonate content, and different geotechnical properties and different bioturbation structures than stations below the OMZ on the abyssal plain. These differences are related to the degree of anoxia and to water depth. Within the OMZ, Eh, pH and carbonate increased with water depth, and TOM and water content decreased. We also noted the presence of subsurface sediment heterogeneity on the continental slope within the OMZ. In the OMZ, Eh, water content and bioturbation decreased with increasing sediment depth. There was a slight decrease in pH in the top 5 cm at all stations. Shear strength nearly always increased with increasing sediment depth. At each water depth correlations show down-core trends in these parameters, while across all water depths correlations were significant at deeper sediment depths (20-30 cm). An Eh-pH diagram identified two water-depth groupings: 391-1008 and 1265-3396 m. Cluster analysis showed the upper and lower sediment depths form separate clusters, the break occurring at 4-7.5 cm; while there are also distinct clusters related to water depth. We relate our results to bottom-water oxygen concentrations reported by other investigators, and to regional-scale geochemical processes.

  16. Modelling vegetation water-use and groundwater recharge as affected by climate variability in an arid-zone Acacia savanna woodland

    NASA Astrophysics Data System (ADS)

    Chen, Chao; Eamus, Derek; Cleverly, James; Boulain, Nicolas; Cook, Peter; Zhang, Lu; Cheng, Lei; Yu, Qiang

    2014-11-01

    For efficient and sustainable utilisation of limited groundwater resources, improved understanding of how vegetation water-use responds to climate variation and the corresponding controls on recharge is essential. This study investigated these responses using a modelling approach. The biophysically based model WAVES was calibrated and validated with more than two years of field experimental data conducted in Mulga (Acacia aneura) in arid central Australia. The validated model was then applied to simulate vegetation growth (as changes in overstory and understory leaf area index; LAI), vegetation water-use and groundwater recharge using observed climate data for the period 1981-2012. Due to large inter-annual climatic variability, especially precipitation, simulated annual mean LAI ranged from 0.12 to 0.35 for the overstory and 0.07 to 0.21 for the understory. These variations in simulated LAI resulted in vegetation water-use varying greatly from year-to-year, from 64 to 601 mm pa. Simulated vegetation water-use also showed distinct seasonal patterns. Vegetation dynamics affected by climate variability exerted significant controls on simulated annual recharge, which was greatly reduced to 0-48 mm compared to that (58-672 mm) only affected by climate. Understanding how climate variability and land use/land cover change interactively impact on groundwater recharge significantly improves groundwater resources management in arid and semi-arid regions.

  17. Factors affecting women’s intention to use long acting and permanent contraceptive methods in Wolaita Zone, Southern Ethiopia: A cross-sectional study

    PubMed Central

    2014-01-01

    Background The use of long acting and permanent contraceptive methods (LAPMs) has not kept step with that of short-acting methods such as oral pills and injectable in Africa. This study explores the association between women’s awareness, attitude and barriers with their intention to use LAPMs among users of short term methods, in Southern Ethiopia. Methods A cross-sectional study design of mixed methods was conducted in the public health facilities of Wolaita zone, Southern Ethiopia, in January 2013. Women who were using short term contraceptive methods were the study population (n = 416). Moreover, 12 in-depth interviews were conducted among family planning providers and women who have been using short term methods. Data were entered into EPI Info version 3.5.3 and exported to SPSS version 16.0 for analysis. The odds ratios in the binary logistic regression model along with 95% confidence interval were used. Results One hundred fifty six (38%) of women had the intention to use LAPMs while nearly half of them (n = 216) had a negative attitude to use such methods. Moreover, two-third of study participants (n = 276) held myths and misconceptions about such methods. The women who had a positive attitude were found to be 2.5 times more intention to use LAPMs compared to women who had a negative attitude (AOR =2. 47; 95% CI: 1.48- 4.11). Women who had no myths and misconceptions on LAPMs were found to be 1.7 times more intention to use LAPMs compared to women who had myths and misconceptions (AOR = 1.71; 95% CI: 1.08- 2.72). Likewise, women who attained secondary and higher level of education were found to be 2 and 2.8 times more intention to use LAPMs compared to women with no education, respectively (AOR = 2. 10; 95% CI: 1.11- 3.98) and AOR = 2. 80; 95% CI: 1.15- 6.77). Conclusions Intention to use LAPMs was low and nearly half of women had a negative attitude to use such methods. Positive attitude, absence of myths and misconceptions on

  18. Recent (2008-10) water quality in the Barton Springs segment of the Edwards aquifer and its contributing zone, central Texas, with emphasis on factors affecting nutrients and bacteria

    USGS Publications Warehouse

    Mahler, Barbara J.; Musgrove, MaryLynn; Sample, Thomas L.; Wong, Corinne I.

    2011-01-01

    The Barton Springs zone, which comprises the Barton Springs segment of the Edwards aquifer and the watersheds to the west that contribute to its recharge, is in south-central Texas, an area with rapid growth in population and increasing amounts of land area affected by development. During November 2008-March 2010, an investigation of factors affecting the fate and transport of nutrients and bacteria in the Barton Springs zone was conducted by the U.S. Geological Survey (USGS), in cooperation with the Texas Commission on Environmental Quality. The primary objectives of the study were to characterize occurrence of nutrients and bacteria in the Barton Springs zone under a range of flow conditions; to improve understanding of the interaction between surface-water quality and groundwater quality; and to evaluate how factors such as streamflow variability and dilution affect the fate and transport of nutrients and bacteria in the Barton Springs zone. The USGS collected and analyzed water samples from five streams (Barton, Williamson, Slaughter, Bear, and Onion Creeks), two groundwater wells (Marbridge and Buda), and the main orifice of Barton Springs in Austin, Texas. During the period of the study, during which the hydrologic conditions transitioned from exceptional drought to wetter than normal, water samples were collected routinely (every 3 to 4 weeks) from the streams, wells, and spring and, in response to storms, from the streams and spring. All samples were analyzed for major ions, nutrients, the bacterium Escherichia coli, and suspended sediment. During the dry period, the geochemistry of groundwater at the two wells and at Barton Springs was dominated by flow from the aquifer matrix and was relatively similar and unchanging at the three sites. At the onset of the wet period, when the streams began to flow, the geochemistry of groundwater samples from the Marbridge well and Barton Springs changed rapidly, and concentrations of most major ions and nutrients and

  19. Investigation of the Kinetics of the Ferrite/Austenite Phase Transformation in the HAZ of a 2205 Duplex Stainless Steel Weldment

    SciTech Connect

    Palmer, T A; Elmer, J W; Wong, J; Babu, S S; Vitek, J M

    2002-03-14

    A semi-quantitative map based on a series of spatially resolved X-ray diffraction (SRXRD) scans shows the progression of the ferrite ({delta})/austenite ({gamma}) phase balance throughout the HAZ during GTA welding of a 2205 duplex stainless steel (DSS). This map shows an unexpected decrease in the ferrite fraction on heating, followed by a recovery to the original ferrite fraction on cooling at locations within the HAZ. Even though such behavior is supported by thermodynamic calculations, it has not been confirmed by either experimental methods or have the kinetics been evaluated. Both Gleeble thermal simulations and time resolved x-ray diffraction measurements on spot welds in the 2205 DSS provide further evidence for this rather low-temperature transformation. On the other hand, calculations of the diffusion of alloying elements across the 6/y interface under a variety of conditions shed no further light on the driving force for this transformation. Further work on the mechanisms and driving forces for this transformation is on-going.

  20. Hydrogeology, Water Chemistry, and Factors Affecting the Transport of Contaminants in the Zone of Contribution of a Public-Supply Well in Modesto, Eastern San Joaquin Valley, California

    USGS Publications Warehouse

    Jurgens, Bryant C.; Burow, Karen R.; Dalgish, Barbara A.; Shelton, Jennifer L.

    2008-01-01

    Ground-water chemistry in the zone of contribution of a public-supply well in Modesto, California, was studied by the U.S. Geological Survey National Water Quality Assessment (NAWQA) Program's topical team for Transport of Anthropogenic and Natural Contaminants (TANC) to supply wells. Twenty-three monitoring wells were installed in Modesto to record baseline hydraulic information and to collect water-quality samples. The monitoring wells were divided into four categories that represent the chemistry of different depths and volumes of the aquifer: (1) water-table wells were screened between 8.5 and 11.7 m (meter) (28 and 38.5 ft [foot]) below land surface (bls) and were within 5 m (16 ft) of the water table; (2) shallow wells were screened between 29 and 35 m (95 and 115 ft) bls; (3) intermediate wells were screened between 50.6 and 65.5 m (166 and 215 ft) bls; and (4) deep wells are screened between 100 to 106 m (328 and 348 ft) bls. Inorganic, organic, isotope, and age-dating tracers were used to characterize the geochemical conditions in the aquifer and understand the mechanisms of mobilization and movement of selected constituents from source areas to a public-supply well. The ground-water system within the study area has been significantly altered by human activities. Water levels in monitoring wells indicated that horizontal movement of ground water was generally from the agricultural areas in the northeast towards a regional water-level depression within the city in the southwest. However, intensive pumping and irrigation recharge in the study area has caused large quantities of ground water to move vertically downward within the regional and local flow systems. Analysis of age tracers indicated that ground-water age varied from recent recharge at the water table to more than 1,000 years in the deep part of the aquifer. The mean age of shallow ground water was determined to be between 30 and 40 years. Intermediate ground water was determined to be a mixture

  1. Investigations Into the Influence of Weld Zone on Formability of Fiber Laser-Welded Advanced High Strength Steel

    NASA Astrophysics Data System (ADS)

    Bandyopadhyay, K.; Panda, S. K.; Saha, P.

    2014-04-01

    In this study, two different dual phase steel grades DP980 and DP600, and IFHS steel sheets were laser welded by a 2-kW fiber laser. The weld quality of these three different LWBs was assessed with the help of microstructure, micro-hardness and transverse tensile tests. Tensile testing of longitudinal and miniature samples was performed to evaluate the mechanical properties of the weld zone. Formability of parent materials and LWBs were assessed in bi-axial stretch forming condition by Erichsen cupping test. To validate the weld zone properties, 3-D finite element models of Erichsen cupping test of LWBs was developed, and the failures in the deformed cups were predicted using two theoretical forming limit diagrams. It was observed that hardness of the fusion zone and HAZ in laser welded DP600 and IFHS steels was more compared to the respective parent metal. However, 29% reduction in hardness was observed at the outer HAZ of DP980 steel weldments due to tempering of martensite. Reduction of formability was observed for all the LWBs with two distinct failure patterns, and the maximum reduction in formability was observed in the case of DP980 LWBs. The presence of the soft zone is detrimental in forming of welded DP steels.

  2. Fusion zone microstructure and porosity in electron beam welds of an α+β titanium alloy

    NASA Astrophysics Data System (ADS)

    Mohandas, T.; Banerjee, D.; Kutumba Rao, V. V.

    1999-03-01

    The effect of electron beam welding parameters on fusion zone (FZ) microstructure and porosity in a Ti -6.8 Al -3.42 Mo -1.9 Zr -0.21 Si alloy (Russian designation VT 9) has been investigated. It has been observed that the FZ grain width increased continuously with increase in heat input when the base metal was in the β heat-treated condition, while in the α+β heat-treated base metal welds, the FZ grain width increased only after a threshold energy input. The difference is attributed to both the weld thermal cycle and the pinning effect of equiaxed primary alpha on grain growth in the heat-affected zone (HAZ) of α+β heat-treated base metal. Postweld heat treatment (PWHT) in the subtransus and supertransus regions did not alter the columnar grain morphology in the FZ, possibly due to the lack of enough driving force for the formation of new grains by the breaking up of the columnar grains and grain boundary movement for grain growth. As the PWHTs were conducted in a furnace, the role of thermal gradients can be ruled out. Intragranular microstructure in the aswelded condition consisted of hexagonal martensite. The scale of the martensite laths depended on welding speed. The highest porosity was observed at intermediate welding speeds. At low speeds, a majority of pores formed at the fusion boundary, while at high speeds, occurrence of porosity was maximum at the weld center. The trends on porosity can be explained on the basis of solubility of hydrogen in titanium as a function of temperature and the influence of weld thermal cycle on nucleation, growth, and escape of hydrogen gas bubbles. The porosity at slow welding speeds is low because sufficient time exists for the nucleation, growth, and escape of hydrogen gas bubbles, while insufficient time exists for the nucleation of gas bubbles at high welding speeds. The effect of pickling of joint surface, vacuum annealing of the base metal, and successive remelting of the weld metal has also been investigated.

  3. Twin Convergence Zones

    NASA Technical Reports Server (NTRS)

    2002-01-01

    NASA's QuikSCAT satellite has confirmed a 30-year old largely unproven theory that there are two areas near the equator where the winds converge year after year and drive ocean circulation south of the equator. By analyzing winds, QuikSCAT has found a year-round southern and northern Intertropical Convergence Zone. This find is important to climate modelers and weather forecasters because it provides more detail on how the oceans and atmosphere interact near the equator. The Intertropical Convergence Zone (ITCZ) is the region that circles the Earth near the equator, where the trade winds of both the Northern and Southern Hemispheres come together. North of the equator, strong sun and warm water of the equator heats the air in the ITCZ, drawing air in from north and south and causing the air to rise. As the air rises it cools, releasing the accumulated moisture in an almost perpetual series of thunderstorms. Satellite data, however, has confirmed that there is an ITCZ north of the equator and a parallel ITCZ south of the equator. Variation in the location of the ITCZ is important to people around the world because it affects the north-south atmospheric circulation, which redistributes energy. It drastically affects rainfall in many equatorial nations, resulting in the wet and dry seasons of the tropics rather than the cold and warm seasons of higher latitudes. Longer term changes in the ITCZ can result in severe droughts or flooding in nearby areas. 'The double ITCZ is usually only identified in the Pacific and Atlantic Oceans on a limited and seasonal basis,' said Timothy Liu, of NASA's Jet Propulsion Laboratory and California Institute of Technology, Pasadena, Calif., and lead researcher on the project. In the eastern Pacific Ocean, the southern ITCZ is usually seen springtime. In the western Atlantic Ocean, the southern ITCZ was recently clearly identified only in the summertime. However, QuikSCAT's wind data has seen the southern ITCZ in all seasons across the

  4. 49 CFR 1105.9 - Coastal Zone Management Act requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Coastal Zone Management Act requirements. 1105.9... ENVIRONMENTAL LAWS § 1105.9 Coastal Zone Management Act requirements. (a) If the proposed action affects land or water uses within a State coastal zone designated pursuant to the Coastal Zone Management Act (16...

  5. 32 CFR 643.33 - Policy-Coastal zone management.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Policy-Coastal zone management. 643.33 Section... PROPERTY REAL ESTATE Policy § 643.33 Policy—Coastal zone management. (a) The Coastal Zone Management Act of... affecting the coastal zone of a state, to conduct or support those activities in a manner which is, to...

  6. Oil-Ash Corrosion Resistance of Dissimilar T22/T91 Welded Joint of Super Heater Tubes

    NASA Astrophysics Data System (ADS)

    Mittal, Rutash; Sidhu, Buta Singh

    2015-02-01

    The studies on the high temperature corrosion of the dissimilar metal weldment are necessary for longer service of the weldments in corrosive medium. This paper reports the performance of microstructurally different regions, namely heat-affected zone (HAZ), weld metal (WM), and base metal (BM) of dissimilar metal weldment of T22/T91 in the molten salt (Na2SO4-60%V2O5) environment under cyclic studies. The T22 HAZ, WM, and T91 HAZ were observed to oxidize at higher rates and develop more scale thickness than other regions in the weldment. Microstructures and elemental analysis indicate lesser availability of Cr in T22 HAZ and T91 HAZ due to formation of Cr-rich phases, which ultimately causes the difference in oxidation behavior of different regions. The presence of chromium carbides and intermetallics in un-oxidized T22 HAZ region and martensitic structure with the presence of delta ferrites in un-oxidized T91 HAZ region was observed to be the major cause behind the weak corrosion resistance of the respective HAZs. The higher oxidation rate of T22 HAZ may be attributed to the absence of protective scale of Cr2O3 and presence of Fe3O4 phases. Similarly higher oxidation rate of T91 HAZ region can be attributed to lesser availability of Cr due to the propensity of development of delta ferrite in martensitic structure.

  7. 36 CFR 13.430 - Determination of resident zones.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... public hearing in the affected local vicinity, a community or area near a national park or monument may be— (1) Added to a resident zone; or (2) Deleted from a resident zone, when such community or...

  8. Modeling of residual stresses by HY-100 weldments

    SciTech Connect

    Zacharia, T.; Taljat, B.; Radhakrishnan, B.

    1997-02-01

    Residual stress distribution in a HY-100 steel disk, induced by GTA spot welding, was analyzed by finite element (FE) formulations and measured by neutron diffraction (ND). Computations used temperature- dependent thermophysical and mechanical properties. FE model predictions are in good agreement with ND data in far heat affected zone (HAZ) and in base metal. Predicted residual stresses in fusion zone and near HAZ were higher than those measured by ND. This discrepancy was attributed to microstructural changes and associated material properties in the HAZ and fusion zone due to phase transformations during the weld thermal cycle.

  9. Climate change and dead zones.

    PubMed

    Altieri, Andrew H; Gedan, Keryn B

    2015-04-01

    Estuaries and coastal seas provide valuable ecosystem services but are particularly vulnerable to the co-occurring threats of climate change and oxygen-depleted dead zones. We analyzed the severity of climate change predicted for existing dead zones, and found that 94% of dead zones are in regions that will experience at least a 2 °C temperature increase by the end of the century. We then reviewed how climate change will exacerbate hypoxic conditions through oceanographic, ecological, and physiological processes. We found evidence that suggests numerous climate variables including temperature, ocean acidification, sea-level rise, precipitation, wind, and storm patterns will affect dead zones, and that each of those factors has the potential to act through multiple pathways on both oxygen availability and ecological responses to hypoxia. Given the variety and strength of the mechanisms by which climate change exacerbates hypoxia, and the rates at which climate is changing, we posit that climate change variables are contributing to the dead zone epidemic by acting synergistically with one another and with recognized anthropogenic triggers of hypoxia including eutrophication. This suggests that a multidisciplinary, integrated approach that considers the full range of climate variables is needed to track and potentially reverse the spread of dead zones.

  10. Climate change and dead zones.

    PubMed

    Altieri, Andrew H; Gedan, Keryn B

    2015-04-01

    Estuaries and coastal seas provide valuable ecosystem services but are particularly vulnerable to the co-occurring threats of climate change and oxygen-depleted dead zones. We analyzed the severity of climate change predicted for existing dead zones, and found that 94% of dead zones are in regions that will experience at least a 2 °C temperature increase by the end of the century. We then reviewed how climate change will exacerbate hypoxic conditions through oceanographic, ecological, and physiological processes. We found evidence that suggests numerous climate variables including temperature, ocean acidification, sea-level rise, precipitation, wind, and storm patterns will affect dead zones, and that each of those factors has the potential to act through multiple pathways on both oxygen availability and ecological responses to hypoxia. Given the variety and strength of the mechanisms by which climate change exacerbates hypoxia, and the rates at which climate is changing, we posit that climate change variables are contributing to the dead zone epidemic by acting synergistically with one another and with recognized anthropogenic triggers of hypoxia including eutrophication. This suggests that a multidisciplinary, integrated approach that considers the full range of climate variables is needed to track and potentially reverse the spread of dead zones. PMID:25385668

  11. Root apex transition zone as oscillatory zone.

    PubMed

    Baluška, František; Mancuso, Stefano

    2013-01-01

    Root apex of higher plants shows very high sensitivity to environmental stimuli. The root cap acts as the most prominent plant sensory organ; sensing diverse physical parameters such as gravity, light, humidity, oxygen, and critical inorganic nutrients. However, the motoric responses to these stimuli are accomplished in the elongation region. This spatial discrepancy was solved when we have discovered and characterized the transition zone which is interpolated between the apical meristem and the subapical elongation zone. Cells of this zone are very active in the cytoskeletal rearrangements, endocytosis and endocytic vesicle recycling, as well as in electric activities. Here we discuss the oscillatory nature of the transition zone which, together with several other features of this zone, suggest that it acts as some kind of command center. In accordance with the early proposal of Charles and Francis Darwin, cells of this root zone receive sensory information from the root cap and instruct the motoric responses of cells in the elongation zone.

  12. Root Apex Transition Zone As Oscillatory Zone

    PubMed Central

    Baluška, František; Mancuso, Stefano

    2013-01-01

    Root apex of higher plants shows very high sensitivity to environmental stimuli. The root cap acts as the most prominent plant sensory organ; sensing diverse physical parameters such as gravity, light, humidity, oxygen, and critical inorganic nutrients. However, the motoric responses to these stimuli are accomplished in the elongation region. This spatial discrepancy was solved when we have discovered and characterized the transition zone which is interpolated between the apical meristem and the subapical elongation zone. Cells of this zone are very active in the cytoskeletal rearrangements, endocytosis and endocytic vesicle recycling, as well as in electric activities. Here we discuss the oscillatory nature of the transition zone which, together with several other features of this zone, suggest that it acts as some kind of command center. In accordance with the early proposal of Charles and Francis Darwin, cells of this root zone receive sensory information from the root cap and instruct the motoric responses of cells in the elongation zone. PMID:24106493

  13. Vadose zone microbiology

    SciTech Connect

    Kieft, Thomas L.; Brockman, Fred J.

    2001-01-17

    The vadose zone is defined as the portion of the terrestrial subsurface that extends from the land surface downward to the water table. As such, it comprises the surface soil (the rooting zone), the underlying subsoil, and the capillary fringe that directly overlies the water table. The unsaturated zone between the rooting zone and the capillary fringe is termed the "intermediate zone" (Chapelle, 1993). The vadose zone has also been defined as the unsaturated zone, since the sediment pores and/or rock fractures are generally not completely water filled, but instead contain both water and air. The latter characteristic results in the term "zone of aeration" to describe the vadose zone. The terms "vadose zone," "unsaturated zone", and "zone of aeration" are nearly synonymous, except that the vadose zone may contain regions of perched water that are actually saturated. The term "subsoil" has also been used for studies of shallow areas of the subsurface immediately below the rooting zone. This review focuses almost exclusively on the unsaturated region beneath the soil layer since there is already an extensive body of literature on surface soil microbial communities and process, e.g., Paul and Clark (1989), Metting (1993), Richter and Markowitz, (1995), and Sylvia et al. (1998); whereas the deeper strata of the unsaturated zone have only recently come under scrutiny for their microbiological properties.

  14. Deciphering a multistage history affecting U-Cu(-Fe) mineralization in the Singhbhum Shear Zone, eastern India, using pyrite textures and compositions in the Turamdih U-Cu(-Fe) deposit

    NASA Astrophysics Data System (ADS)

    Pal, Dipak C.; Barton, Mark D.; Sarangi, A. K.

    2009-01-01

    The ˜200-km-long intensely deformed Singhbhum Shear Zone (SSZ) in eastern India hosts India’s largest U and Cu deposits and related Fe mineralization. The SSZ separates an Archaean cratonic nucleus to the south from a Mesoproterozoic fold belt in the North and has a complex geologic history that obscures the origin of the contained iron-oxide-rich mineral deposits. This study investigates aspects of the history of mineralization in the SSZ by utilizing new petrographic and electron microprobe observations of pyrite textures and zoning in the Turamdih U-Cu(-Fe) deposit. Mineralization at Turamdih is hosted in intensively deformed quartz-chlorite schist. Sulfides and oxides include, in inferred order of development: (a) magmatic Fe(-Ti-Cr) oxide and Fe-Cu(-Ni) sulfide minerals inferred to be magmatic (?) in origin; followed by (b) uranium, Fe-oxide, and Fe-Cu(-Co) sulfide minerals that predate most or all ductile deformation, and are inferred to be of hydrothermal origin; and (c) Fe-Cu sulfides that were generated during and postdating ductile deformation. These features are associated with the formation of three compositionally and texturally distinct pyrites. Pyrite (type-A), typically in globular-semiglobular composite inclusions of pyrite plus chalcopyrite in magnetite, is characterized by very high Ni content (up to 30,700 ppm) and low Co to Ni ratios (0.01-0.61). The textural and compositional characteristics of associated chalcopyrite and rare pyrrhotite suggest that this pyrite could be linked to the magmatic event via selective replacement of magmatic pyrrhotite. Alternatively, this pyrite and associated sulfide inclusions might be cogenetic with hydrothermal Fe-oxide. Type-B pyrite that forms elongate grains and irregular relics and cores of pyrite with high Co contents (up to 23,630 ppm) and high Co to Ni ratios (7.2-140.9) are interpreted to be related to hydrothermal mineralization predating ductile deformation. A third generation of pyrite (type C

  15. [Dynamics of Radioecological State of the Fresh-Water Ecosystems Affected by a Long-Term Impact from Nuclear Power Plant in the Frontiers of the Zone under Observation].

    PubMed

    Trapeznikov, A V; Trapeznikova, V N; Korjavin, A V

    2015-01-01

    The results of radioecological studies of six small rivers situated in the surveillance zone of the Beloyarskaya NPP (BNPP) and around the cooling pond of the power plant are presented. 21 radionuclides and the total α- and β-activity were studied in the main components of the aquatic ecosystems. It is shown that after the 1st and 2nd BN PP blocks decommissioning the content of 60Co and 137Cs in the Beloyarskoye storage pond water, sediments, fish fauna and macrophytes dropped tens and hundreds of times. The fundamental importance of this fact is that in a large range of time the aquatic ecosystem mechanism of self-purification from radionuclides is working due to radioactive substances decay as well as redistribution of radionuclides from water to other components, primarily to the sediments. Of 6 small rivers the maximum levels of radioactive substances is found in the river Olkhovka, which for several years has been subjected to the low-level radioactive water discharges from Beloyarskaya NPP. The radionuclide content in the main components of the aquatic ecosystems of the other five rivers studied after BNPP 47-year operation period corresponds to the regional background. PMID:26310022

  16. Zone Refining by Laser

    NASA Technical Reports Server (NTRS)

    Griner, D. B.

    1986-01-01

    System developed for studying use of laser beam for zone-refining semiconductors and metals. Specimen scanned with focused CO2 laser beam in such way that thin zone of molten material moves along specimen sweeps impurities with it. Zone-melting system comprises microcomputer, laser, electromechanical and optical components for beam control, vacuum chamber that holds specimen, and sensor for determining specimen temperature.

  17. Conservation of the Red Kite Milvus milvus (Aves: Accipitriformes) Is Not Affected by the Establishment of a Broad Hybrid Zone with the Black Kite Milvus migrans migrans in Central Europe

    PubMed Central

    Matušík, Hynek; Pfeiffer, Thomas; Nachtigall, Winfried; Bizos, Jiří; Šimčíková, Daniela; Literák, Ivan

    2016-01-01

    Among Accipitriformes sensu stricto, only a few species have been reported to form hybrid zones; these include the red kite Milvus milvus and black kite Milvus migrans migrans. M. milvus is endemic to the western Palearctic and has an estimated total population of 20–24,000 breeding pairs. The species was in decline until the 1970s due to persecution and has declined again since the 1990s due to ingestion of rodenticide-treated baits, illegal poisoning and changes in agricultural practices, particularly in its core range. Whereas F1 M. milvus × M. migr. migrans hybrid offspring have been found, F2 and F3 hybrids have only rarely been reported, with low nesting success rates of F1 hybrids and partial hybrid sterility likely playing a role. Here, we analyzed the mitochondrial (CO1 and CytB) and nuclear (Myc) DNA loci of 184 M. milvus, 124 M. migr. migrans and 3 F1 hybrid individuals collected across central Europe. In agreement with previous studies, we found low heterozygosity in M. milvus regardless of locus. We found that populations of both examined species were characterized by a high gene flow within populations, with all of the major haplotypes distributed across the entire examined area. Few haplotypes displayed statistically significant aggregation in one region over another. We did not find mitochondrial DNA of one species in individuals with the plumage of the other species, except in F1 hybrids, which agrees with Haldane´s Rule. It remains to be investigated by genomic methods whether occasional gene flow occurs through the paternal line, as the examined Myc gene displayed only marginal divergence between M. milvus and M. migr. migrans. The central European population of M. milvus is clearly subject to free intraspecific gene flow, which has direct implications when considering the origin of individuals in M. milvus re-introduction programs. PMID:27463515

  18. Conservation of the Red Kite Milvus milvus (Aves: Accipitriformes) Is Not Affected by the Establishment of a Broad Hybrid Zone with the Black Kite Milvus migrans migrans in Central Europe.

    PubMed

    Heneberg, Petr; Dolinay, Matej; Matušík, Hynek; Pfeiffer, Thomas; Nachtigall, Winfried; Bizos, Jiří; Šimčíková, Daniela; Literák, Ivan

    2016-01-01

    Among Accipitriformes sensu stricto, only a few species have been reported to form hybrid zones; these include the red kite Milvus milvus and black kite Milvus migrans migrans. M. milvus is endemic to the western Palearctic and has an estimated total population of 20-24,000 breeding pairs. The species was in decline until the 1970s due to persecution and has declined again since the 1990s due to ingestion of rodenticide-treated baits, illegal poisoning and changes in agricultural practices, particularly in its core range. Whereas F1 M. milvus × M. migr. migrans hybrid offspring have been found, F2 and F3 hybrids have only rarely been reported, with low nesting success rates of F1 hybrids and partial hybrid sterility likely playing a role. Here, we analyzed the mitochondrial (CO1 and CytB) and nuclear (Myc) DNA loci of 184 M. milvus, 124 M. migr. migrans and 3 F1 hybrid individuals collected across central Europe. In agreement with previous studies, we found low heterozygosity in M. milvus regardless of locus. We found that populations of both examined species were characterized by a high gene flow within populations, with all of the major haplotypes distributed across the entire examined area. Few haplotypes displayed statistically significant aggregation in one region over another. We did not find mitochondrial DNA of one species in individuals with the plumage of the other species, except in F1 hybrids, which agrees with Haldane´s Rule. It remains to be investigated by genomic methods whether occasional gene flow occurs through the paternal line, as the examined Myc gene displayed only marginal divergence between M. milvus and M. migr. migrans. The central European population of M. milvus is clearly subject to free intraspecific gene flow, which has direct implications when considering the origin of individuals in M. milvus re-introduction programs. PMID:27463515

  19. Conservation of the Red Kite Milvus milvus (Aves: Accipitriformes) Is Not Affected by the Establishment of a Broad Hybrid Zone with the Black Kite Milvus migrans migrans in Central Europe.

    PubMed

    Heneberg, Petr; Dolinay, Matej; Matušík, Hynek; Pfeiffer, Thomas; Nachtigall, Winfried; Bizos, Jiří; Šimčíková, Daniela; Literák, Ivan

    2016-01-01

    Among Accipitriformes sensu stricto, only a few species have been reported to form hybrid zones; these include the red kite Milvus milvus and black kite Milvus migrans migrans. M. milvus is endemic to the western Palearctic and has an estimated total population of 20-24,000 breeding pairs. The species was in decline until the 1970s due to persecution and has declined again since the 1990s due to ingestion of rodenticide-treated baits, illegal poisoning and changes in agricultural practices, particularly in its core range. Whereas F1 M. milvus × M. migr. migrans hybrid offspring have been found, F2 and F3 hybrids have only rarely been reported, with low nesting success rates of F1 hybrids and partial hybrid sterility likely playing a role. Here, we analyzed the mitochondrial (CO1 and CytB) and nuclear (Myc) DNA loci of 184 M. milvus, 124 M. migr. migrans and 3 F1 hybrid individuals collected across central Europe. In agreement with previous studies, we found low heterozygosity in M. milvus regardless of locus. We found that populations of both examined species were characterized by a high gene flow within populations, with all of the major haplotypes distributed across the entire examined area. Few haplotypes displayed statistically significant aggregation in one region over another. We did not find mitochondrial DNA of one species in individuals with the plumage of the other species, except in F1 hybrids, which agrees with Haldane´s Rule. It remains to be investigated by genomic methods whether occasional gene flow occurs through the paternal line, as the examined Myc gene displayed only marginal divergence between M. milvus and M. migr. migrans. The central European population of M. milvus is clearly subject to free intraspecific gene flow, which has direct implications when considering the origin of individuals in M. milvus re-introduction programs.

  20. Fluid processes in subduction zones.

    PubMed

    Peacock, S A

    1990-04-20

    Fluids play a critical role in subduction zones and arc magmatism. At shallow levels in subduction zones (<40 kilometers depth), expulsion of large volumes of pore waters and CH(4)-H(2)O fluids produced by diagenetic and low-grade metamorphic reactions affect the thermal and rheological evolution of the accretionary prism and provide nutrients for deep-sea biological communities. At greater depths, H(2)O and CO(2) released by metamorphic reactions in the subducting oceanic crust may alter the bulk composition in the overlying mantle wedge and trigger partial melting reactions. The location and conse-quences of fluid production in subduction zones can be constrained by consideration of phase diagrams for relevant bulk compositions in conjunction with fluid and rock pressure-temperature-time paths predicted by numerical heat-transfer models. Partial melting of subducting, amphibole-bearing oceanic crust is predicted only within several tens of million years of the initiation of subduction in young oceanic lithosphere. In cooler subduction zones, partial melting appears to occur primarily in the overlying mantle wedge as a result of fluid infiltration. PMID:17784486

  1. Fluid processes in subduction zones.

    PubMed

    Peacock, S A

    1990-04-20

    Fluids play a critical role in subduction zones and arc magmatism. At shallow levels in subduction zones (<40 kilometers depth), expulsion of large volumes of pore waters and CH(4)-H(2)O fluids produced by diagenetic and low-grade metamorphic reactions affect the thermal and rheological evolution of the accretionary prism and provide nutrients for deep-sea biological communities. At greater depths, H(2)O and CO(2) released by metamorphic reactions in the subducting oceanic crust may alter the bulk composition in the overlying mantle wedge and trigger partial melting reactions. The location and conse-quences of fluid production in subduction zones can be constrained by consideration of phase diagrams for relevant bulk compositions in conjunction with fluid and rock pressure-temperature-time paths predicted by numerical heat-transfer models. Partial melting of subducting, amphibole-bearing oceanic crust is predicted only within several tens of million years of the initiation of subduction in young oceanic lithosphere. In cooler subduction zones, partial melting appears to occur primarily in the overlying mantle wedge as a result of fluid infiltration.

  2. Coastal Zone Color Scanner

    NASA Technical Reports Server (NTRS)

    Johnson, B.

    1988-01-01

    The Coastal Zone Color Scanner (CZCS) spacecraft ocean color instrument is capable of measuring and mapping global ocean surface chlorophyll concentration. It is a scanning radiometer with multiband capability. With new electronics and some mechanical, and optical re-work, it probably can be made flight worthy. Some additional components of a second flight model are also available. An engineering study and further tests are necessary to determine exactly what effort is required to properly prepare the instrument for spaceflight and the nature of interfaces to prospective spacecraft. The CZCS provides operational instrument capability for monitoring of ocean productivity and currents. It could be a simple, low cost alternative to developing new instruments for ocean color imaging. Researchers have determined that with global ocean color data they can: specify quantitatively the role of oceans in the global carbon cycle and other major biogeochemical cycles; determine the magnitude and variability of annual primary production by marine phytoplankton on a global scale; understand the fate of fluvial nutrients and their possible affect on carbon budgets; elucidate the coupling mechanism between upwelling and large scale patterns in ocean basins; answer questions concerning the large scale distribution and timing of spring blooms in the global ocean; acquire a better understanding of the processes associated with mixing along the edge of eddies, coastal currents, western boundary currents, etc., and acquire global data on marine optical properties.

  3. Microgravity silicon zoning investigation

    NASA Technical Reports Server (NTRS)

    Kern, E. L.; Gill, G. L., Jr.

    1983-01-01

    A resistance heated zoner, suitable for early zoning experiments with silicon, was designed and put into operation. The initial power usage and size was designed for an shown to be compatible with payload carriers contemplated for the Shuttle. This equipment will be used in the definition and development of flight experiments and apparatus for float zoning silicon and other materials in microgravity.

  4. Float Zone Workshop

    NASA Technical Reports Server (NTRS)

    Naumann, R. J.

    1980-01-01

    A summary of the Analytical Float Zone Experiment System (AFZES) concept is presented. The types of experiments considered for such a facility are discussed. Reports from various industrial producers and users of float zone material are presented. Special emphasis is placed on state-of-the-art developments in low gravity manufacturing and their applications to space processing.

  5. Investigating Aquatic Dead Zones

    ERIC Educational Resources Information Center

    Testa, Jeremy; Gurbisz, Cassie; Murray, Laura; Gray, William; Bosch, Jennifer; Burrell, Chris; Kemp, Michael

    2010-01-01

    This article features two engaging high school activities that include current scientific information, data, and authentic case studies. The activities address the physical, biological, and chemical processes that are associated with oxygen-depleted areas, or "dead zones," in aquatic systems. Students can explore these dead zones through both…

  6. Coastal zone management

    NASA Technical Reports Server (NTRS)

    Tilton, E. L., III

    1975-01-01

    A panel of federal and state representatives concerned with coastal zone affairs discussed their problems in this area. In addition, several demonstrations of the application of remote sensing technology to coastal zone management were described. These demonstrations were performed by several agencies in a variety of geographical areas.

  7. Subduction of fracture zones

    NASA Astrophysics Data System (ADS)

    Constantin Manea, Vlad; Gerya, Taras; Manea, Marina; Zhu, Guizhi; Leeman, William

    2013-04-01

    Since Wilson proposed in 1965 the existence of a new class of faults on the ocean floor, namely transform faults, the geodynamic effects and importance of fracture zone subduction is still little studied. It is known that oceanic plates are characterized by numerous fracture zones, and some of them have the potential to transport into subduction zones large volumes of water-rich serpentinite, providing a fertile water source for magma generated in subduction-related arc volcanoes. In most previous geodynamic studies, subducting plates are considered to be homogeneous, and there is no clear indication how the subduction of a fracture zone influences the melting pattern in the mantle wedge and the slab-derived fluids distribution in the subarc mantle. Here we show that subduction of serpentinized fracture zones plays a significant role in distribution of melt and fluids in the mantle wedge above the slab. Using high-resolution tree-dimensional coupled petrological-termomechanical simulations of subduction, we show that fluids, including melts and water, vary dramatically in the region where a serpentinized fracture zone enters into subduction. Our models show that substantial hydration and partial melting tend to concentrate where fracture zones are being subducted, creating favorable conditions for partially molten hydrous plumes to develop. These results are consistent with the along-arc variability in magma source compositions and processes in several regions, as the Aleutian Arc, the Cascades, the Southern Mexican Volcanic Arc, and the Andean Southern Volcanic Zone.

  8. The Law of the People (Dine Bibee Haz'Aannii): A Bicultural Approach to Legal Education for Navajo Students, Volume 4.

    ERIC Educational Resources Information Center

    Vicenti, Dan; And Others

    Volume 4 of a 4-volume bilingual bicultural law-related curriculum examines Navajo community life as it is affected by certain laws. Getting a job, obtaining assistance from welfare and other agencies, and preserving one's individual rights as an employee or as a student are all aspects of daily living with important legal ramifications. This unit…

  9. Multi-zone furnace system

    SciTech Connect

    Orbeck, G.A.

    1986-05-06

    A multi-zone furnace is described which consists of: a furnace chamber having at least one heat zone and at least one zone adjacent to the heat zone and disposed along the length of the furnace chamber; the heat zone having a hearth at a level different from the hearth level of the adjacent zone; a walking beam conveyor disposed in the furnace chamber and operative in a short stroke mode to convey a product along the hearth of the heat zone, and in a long stroke mode to convey a product from the heat zone to the adjacent zone.

  10. Fault zone hydrogeology

    NASA Astrophysics Data System (ADS)

    Bense, V. F.; Gleeson, T.; Loveless, S. E.; Bour, O.; Scibek, J.

    2013-12-01

    Deformation along faults in the shallow crust (< 1 km) introduces permeability heterogeneity and anisotropy, which has an important impact on processes such as regional groundwater flow, hydrocarbon migration, and hydrothermal fluid circulation. Fault zones have the capacity to be hydraulic conduits connecting shallow and deep geological environments, but simultaneously the fault cores of many faults often form effective barriers to flow. The direct evaluation of the impact of faults to fluid flow patterns remains a challenge and requires a multidisciplinary research effort of structural geologists and hydrogeologists. However, we find that these disciplines often use different methods with little interaction between them. In this review, we document the current multi-disciplinary understanding of fault zone hydrogeology. We discuss surface- and subsurface observations from diverse rock types from unlithified and lithified clastic sediments through to carbonate, crystalline, and volcanic rocks. For each rock type, we evaluate geological deformation mechanisms, hydrogeologic observations and conceptual models of fault zone hydrogeology. Outcrop observations indicate that fault zones commonly have a permeability structure suggesting they should act as complex conduit-barrier systems in which along-fault flow is encouraged and across-fault flow is impeded. Hydrogeological observations of fault zones reported in the literature show a broad qualitative agreement with outcrop-based conceptual models of fault zone hydrogeology. Nevertheless, the specific impact of a particular fault permeability structure on fault zone hydrogeology can only be assessed when the hydrogeological context of the fault zone is considered and not from outcrop observations alone. To gain a more integrated, comprehensive understanding of fault zone hydrogeology, we foresee numerous synergistic opportunities and challenges for the discipline of structural geology and hydrogeology to co-evolve and

  11. Megacities in the Coastal Zone

    NASA Astrophysics Data System (ADS)

    von Glasow, R.; Jickells, T.; Baklanov, A.; Carmichael, G. R.; Church, T. M.; Gallardo, L.; Hughes, C.; Kanakidou, M.; Liss, P. S.; Mee, L.; Raine, R.; Ramachandran, P.; Ramesh, R.; Sundseth, K.; Tsunogai, U.; Uematsu, M.; Zhu, T.

    2012-04-01

    Megacities have long been recognised as important drivers for socioeconomic development but also as sources of environmental challenges. A large number of megacities are located in the coastal zone where land, atmosphere and ocean meet, posing additional challenges for our understanding of the interactions. The atmospheric flow is complicated not only by urban heat island effects but also topographic flows and sea breezes which also lead to profound changes in clouds and precipitation. Inflow of oceanic air (rich in sea salt) into the polluted city's atmosphere and outflow of polluted air onto a much cleaner ocean lead to very specific interactions, the net effects of which are not well understood. The addition of contaminants to the coastal waters both by atmospheric deposition and fluvial inputs can affect the coastal ecosystems dramatically, limiting their ability to function and provide ecosystem services, e.g. fisheries and aquaculture. Changes to coastal ecosystems also affect fluxes of gases and particles to the atmosphere and can lead to harmful algal blooms. The scale of influence of megacities in the coastal zone is at least hundreds if not thousands of kilometres in the atmosphere and tens to hundreds of kilometres in the ocean, the latter strongly dependent on the hydrographic setting. Coastal megacities are at risk by sea level rise, floods and storms; they are at the forefront of change and scientifically well informed planning can improve livelihoods and ecosystem health but only if we take a holistic approach to study and monitor these regions.

  12. Growth recovery zones.

    PubMed

    Siffert, R S; Katz, J F

    1983-05-01

    Growth arrest lines and zones have been reinvestigated. Sequential studies after dietary deprivation reveal transformations of the physis with diminution in formation of the zone of cell columns, resorption of previously formed bone, and cessation of new bone formation. At 6 weeks post diet restriction, the physis is prominently narrowed with transversely oriented, thin bone plaque sealing it from the subjacent marrow. Initially, restoration of stock diet thickens the bony plaque, creating a growth arrest line. Later the zone of osteogenesis adds new bone as a dense metaphyseal band.

  13. Affective Learning.

    ERIC Educational Resources Information Center

    Brown, Charles T.

    This paper addresses itself to the question, "What does feeling have to do with knowing?" Two movements in affective education are discussed which have come into focus in recent years and which attempt to define the relationship between knowing and feeling. The first, a conscious application of the role of arousal in learning, emphasizes arousal…

  14. The gray zone.

    PubMed

    Kisner, H J

    1998-01-01

    Think for a minute about the terms equivocal and indeterminate. Equivocal is defined as "of uncertain significance", and indeterminate is defined as "indefinite, uncertain". Now think of the context in which laboratory results are reported: either by using the exact words equivocal or indeterminate or cloaked in technical jargon (e.g., cytologic diagnoses "ASCUS" or "AGUS"). Clinicians expect (or at least want) laboratory results to be black or white (i.e., bimodally distributed), whereas laboratorians strive for the perfect shade of gray because of data that often are bimodal but overlapping. A consequence of this color war is "the gray zone" (often confused with the "twilight zone"), a noncommittal zone that leaves laboratorians and clinicians alike plenty of wiggle room, allowing us to interpret results on either side of the fence. This article examines the root causes of the gray zone, with several clinical examples of how it permeates laboratory interpretation.

  15. The Ethical Tipping Points of Evaluators in Conflict Zones

    ERIC Educational Resources Information Center

    Duggan, Colleen; Bush, Kenneth

    2014-01-01

    What is different about the conduct of evaluations in conflict zones compared to nonconflict zones--and how do these differences affect (if at all) the ethical calculations and behavior of evaluators? When are ethical issues too risky, or too uncertain, for evaluators to accept--or to continue--an evaluation? These are the core questions guiding…

  16. Cascadia Subduction Zone

    USGS Publications Warehouse

    Frankel, Arthur D.; Petersen, Mark D.

    2008-01-01

    The geometry and recurrence times of large earthquakes associated with the Cascadia Subduction Zone (CSZ) were discussed and debated at a March 28-29, 2006 Pacific Northwest workshop for the USGS National Seismic Hazard Maps. The CSZ is modeled from Cape Mendocino in California to Vancouver Island in British Columbia. We include the same geometry and weighting scheme as was used in the 2002 model (Frankel and others, 2002) based on thermal constraints (Fig. 1; Fluck and others, 1997 and a reexamination by Wang et al., 2003, Fig. 11, eastern edge of intermediate shading). This scheme includes four possibilities for the lower (eastern) limit of seismic rupture: the base of elastic zone (weight 0.1), the base of transition zone (weight 0.2), the midpoint of the transition zone (weight 0.2), and a model with a long north-south segment at 123.8? W in the southern and central portions of the CSZ, with a dogleg to the northwest in the northern portion of the zone (weight 0.5). The latter model was derived from the approximate average longitude of the contour of the 30 km depth of the CSZ as modeled by Fluck et al. (1997). A global study of the maximum depth of thrust earthquakes on subduction zones by Tichelaar and Ruff (1993) indicated maximum depths of about 40 km for most of the subduction zones studied, although the Mexican subduction zone had a maximum depth of about 25 km (R. LaForge, pers. comm., 2006). The recent inversion of GPS data by McCaffrey et al. (2007) shows a significant amount of coupling (a coupling factor of 0.2-0.3) as far east as 123.8? West in some portions of the CSZ. Both of these lines of evidence lend support to the model with a north-south segment at 123.8? W.

  17. Dentin Caries Zones

    PubMed Central

    Pugach, M.K.; Strother, J.; Darling, C.L.; Fried, D.; Gansky, S.A.; Marshall, S.J.; Marshall, G.W.

    2009-01-01

    Caries Detector staining reveals 4 zones in dentin containing caries lesions, but characteristics of each zone are not well-defined. We therefore investigated the physical and microstructural properties of carious dentin in the 4 different zones to determine important differences revealed by Caries Detector staining. Six arrested dentin caries lesions and 2 normal controls were Caries-Detector-stained, each zone (pink, light pink, transparent, apparently normal) being analyzed by atomic force microscopy (AFM) imaging for microstructure, by AFM nano-indentation for mechanical properties, and by transverse digital microradiography (TMR) for mineral content. Microstructure changes, and nanomechanical properties and mineral content significantly decreased across zones. Hydrated elastic modulus and mineral content from normal dentin to pink Caries-Detector-stained dentin ranged from 19.5 [10.6-25.3] GPa to 1.6 [0.0-5.0] GPa and from 42.9 [39.8-44.6] vol% to 12.4 [9.1-14.2] vol%, respectively. Even the most demineralized pink zone contained considerable residual mineral. PMID:19131321

  18. Investigation of Strength Recovery in Welds of NUCu-140 Steel Through Multipass Welding and Isothermal Post-Weld Heat Treatments

    NASA Astrophysics Data System (ADS)

    Bono, Jason T.; DuPont, John N.; Jain, Divya; Baik, Sung-Il; Seidman, David N.

    2015-11-01

    NUCu-140 is a ferritic copper precipitation-strengthened steel that is a candidate material for use in many naval and structural applications. Previous work has shown that the heat-affected zone (HAZ) and fusion zone (FZ) of NUCu-140 exhibit softening that is due to dissolution of the copper-rich precipitates. This study aims to recover the FZ and HAZ strength by re-precipitation of the copper-rich precipitates through either multiple weld passes or an isothermal post-weld heat treatment (PWHT). The potential use of multiple thermal cycles was investigated with HAZ simulations using a Gleeble thermo-mechanical simulator. The HAZ simulations represented two weld thermal cycles with different combinations of peak temperatures during the initial and secondary weld passes. To investigate the potential for a PWHT for strength recovery, gas tungsten arc weld samples were isothermally heated for various times and temperatures. Microhardness measurements revealed no strength recovery in the multipass HAZ samples. The time-dependent precipitate characteristics were modeled under the HAZ thermal cycle conditions, and the results showed that the lack of strength recovery could be attributed to insufficient time for re-precipitation during the secondary weld pass. Conversely, full strength recovery in the HAZ was observed in the isothermally heat treated samples. Atom probe tomography analysis correlated this strength recovery to re-precipitation of the copper-rich precipitates during the isothermal PWHT.

  19. Dead zones and extrasolar planetary properties

    NASA Astrophysics Data System (ADS)

    Matsumura, Soko; Pudritz, Ralph E.

    2006-01-01

    Most low-mass protostellar discs evolve in clustered environments where they are affected by external radiation fields, while others evolve in more isolated star-forming regions. Assuming that the magnetorotational instability (MRI) is the main source of viscosity, we calculate the size of a poorly ionized, MRI inactive and hence low viscosity region - the `dead zone'- in these protostellar discs. We include disc ionization by X-rays, cosmic rays, radioactive elements and thermal collisions, recombination by molecules, metals and grains, as well as the effect of turbulence stimulation in the dead zone by the active layers lying above it. We also calculate the gap-opening masses of planets, which are determined by a disc's viscosity and a disc aspect ratio, for discs in these environments and compare them with each other. We find that the dead zone is a robust feature of the protostellar discs that is largely independent of their environment, typically stretching out to ~15 au. We analyse the possible effects of dead zones on planet formation, migration and eccentricity evolution. We show that the gap-opening mass inside the dead zone is expected to be of the order of terrestrial and ice giant mass planets while that outside the dead zone is Jovian or super-Jovian mass planets, largely independent of the star-forming environment. We show that dead zones can significantly slow down both type I and type II planetary migration due to their lower viscosity. We also find that the growth of eccentricity of massive extrasolar planets is particularly favourable through the planet-disc interaction inside the dead zones due to the large gaps expected to be opened by planets.

  20. Flow, affect and visual creativity.

    PubMed

    Cseh, Genevieve M; Phillips, Louise H; Pearson, David G

    2015-01-01

    Flow (being in the zone) is purported to have positive consequences in terms of affect and performance; however, there is no empirical evidence about these links in visual creativity. Positive affect often--but inconsistently--facilitates creativity, and both may be linked to experiencing flow. This study aimed to determine relationships between these variables within visual creativity. Participants performed the creative mental synthesis task to simulate the creative process. Affect change (pre- vs. post-task) and flow were measured via questionnaires. The creativity of synthesis drawings was rated objectively and subjectively by judges. Findings empirically demonstrate that flow is related to affect improvement during visual creativity. Affect change was linked to productivity and self-rated creativity, but no other objective or subjective performance measures. Flow was unrelated to all external performance measures but was highly correlated with self-rated creativity; flow may therefore motivate perseverance towards eventual excellence rather than provide direct cognitive enhancement.

  1. Softening Behavior of a New Al-Zn-Mg-Cu Alloy Due to TIG Welding

    NASA Astrophysics Data System (ADS)

    Zhang, Liang; Li, Xiaoyan; Nie, Zuoren; Huang, Hui; Sun, Jiantong

    2016-05-01

    A new Al-Zn-Mg-Cu alloy with T6 temper was welded by TIG welding, and the softening behavior of the joint was evaluated. Results show that the ultimate tensile strength of the joint is 436.2 ± 26.4 MPa which is about 64.5% of that of the base metal (BM). Fusion zone (FZ) is the weakest region even though its microhardness increases from 107.6 to 131.3 HV within 90 days after welding. Microhardness of the heat-affected zone (HAZ) adjacent to FZ increases from 125.2 to 162.3 HV within 90 days. However, a valley value of microhardness appears in the rest of the HAZ that increases from 112.1 to 128.1 HV within 90 days. The variation of grain size and precipitates is regarded as the main cause of softening in both FZ and HAZ. The grain size of FZ is about 33.9 μm, whereas 8.7 and 8.4 μm for HAZ and BM, respectively. A large number of η' phases distribute dispersively in BM, whereas precipitates in FZ identified as GPI zones are finer and fewer. Besides, precipitates in HAZ adjacent to FZ are also GPI zones. Precipitates in HAZ far away from FZ are coarser and fewer than those in BM and η phases begin to emerge.

  2. Semiautomatic fracture zone tracking

    NASA Astrophysics Data System (ADS)

    Wessel, Paul; Matthews, Kara J.; Müller, R. Dietmar; Mazzoni, Aline; Whittaker, Joanne M.; Myhill, Robert; Chandler, Michael T.

    2015-07-01

    Oceanic fracture zone traces are widely used in studies of seafloor morphology and plate kinematics. Satellite altimetry missions have resulted in high-resolution gravity maps in which all major fracture zones and other tectonic fabric can be identified, and numerous scientists have digitized such lineaments. We have initiated a community effort to maintain low-cost infrastructure that allows seafloor fabric lineaments to be stored, accessed, and updated. A key improvement over past efforts is our processing software (released as a GMT5 supplement) that allows for semiautomatic corrections to previously digitized fracture zone traces given improved gridded data sets. Here we report on our seafloor fabric processing tools, which complement our database of seafloor fabric lineations, magnetic anomaly identifications, and plate kinematic models.

  3. Nuclear free zone

    SciTech Connect

    Christoffel, T.

    1987-07-01

    Health professionals have played a leading role in alerting and educating the public regarding the danger of nuclear war which has been described as the last epidemic our civilization will know. Having convinced most people that the use of nuclear weapons would mean intolerable consequences, groups such as Physicians for Social Responsibility have focused on the second critical question how likely is it that these weapons will be used. The oultlook is grim. This article describes the nuclear free zone movement, explores relevant legal questions, and shows how the political potential of nuclear free zones threatens to open a deep rift in the American constitutional system.

  4. [Affective dependency].

    PubMed

    Scantamburlo, G; Pitchot, W; Ansseau, M

    2013-01-01

    Affective dependency is characterized by emotional distress (insecure attachment) and dependency to another person with a low self-esteem and reassurance need. The paper proposes a reflection on the definition of emotional dependency and the confusion caused by various denominations. Overprotective and authoritarian parenting, cultural and socio-environmental factors may contribute to the development of dependent personality. Psychological epigenetic factors, such as early socio-emotional trauma could on neuronal circuits in prefronto-limbic regions that are essential for emotional behaviour.We also focus on the interrelations between dependent personality, domestic violence and addictions. The objective for the clinician is to propose a restoration of self-esteem and therapeutic strategies focused on autonomy.

  5. [Affective dependency].

    PubMed

    Scantamburlo, G; Pitchot, W; Ansseau, M

    2013-01-01

    Affective dependency is characterized by emotional distress (insecure attachment) and dependency to another person with a low self-esteem and reassurance need. The paper proposes a reflection on the definition of emotional dependency and the confusion caused by various denominations. Overprotective and authoritarian parenting, cultural and socio-environmental factors may contribute to the development of dependent personality. Psychological epigenetic factors, such as early socio-emotional trauma could on neuronal circuits in prefronto-limbic regions that are essential for emotional behaviour.We also focus on the interrelations between dependent personality, domestic violence and addictions. The objective for the clinician is to propose a restoration of self-esteem and therapeutic strategies focused on autonomy. PMID:23888587

  6. Fast aurora zone analysis

    NASA Technical Reports Server (NTRS)

    Booker, Mattie

    1992-01-01

    The Flight Dynamics Facility (FDF) of the Flight Dynamics Division (FDD), of the Goddard Space Flight Center provides acquisition data to tracking stations and orbit and attitude services to scientists and mission support personnel. The following paper explains how a method was determined that found spacecraft entry and exit times of the aurora zone.

  7. ON HYDRODYNAMIC MOTIONS IN DEAD ZONES

    SciTech Connect

    Oishi, Jeffrey S.; Mac Low, Mordecai-Mark E-mail: mordecai@amnh.or

    2009-10-20

    We investigate fluid motions near the midplane of vertically stratified accretion disks with highly resistive midplanes. In such disks, the magnetorotational instability drives turbulence in thin layers surrounding a resistive, stable dead zone. The turbulent layers in turn drive motions in the dead zone. We examine the properties of these motions using three-dimensional, stratified, local, shearing-box, non-ideal, magnetohydrodynamical simulations. Although the turbulence in the active zones provides a source of vorticity to the midplane, no evidence for coherent vortices is found in our simulations. It appears that this is because of strong vertical oscillations in the dead zone. By analyzing time series of azimuthally averaged flow quantities, we identify an axisymmetric wave mode particular to models with dead zones. This mode is reduced in amplitude, but not suppressed entirely, by changing the equation of state from isothermal to ideal. These waves are too low frequency to affect sedimentation of dust to the midplane, but may have significance for the gravitational stability of the resulting midplane dust layers.

  8. Can Supersaturation Affect Protein Crystal Quality?

    NASA Technical Reports Server (NTRS)

    Gorti, Sridhar

    2013-01-01

    In quiescent environments (microgravity, capillary tubes, gels) formation of a depletion zone is to be expected, due either to limited sedimentation, density driven convection or a combination of both. The formation of a depletion zone can: Modify solution supersaturation near crystal; Give rise to impurity partitioning. It is conjectured that both supersaturation and impurity partitioning affect protein crystal quality and size. Further detailed investigations on various proteins are needed to assess above hypothesis.

  9. Vadose zone water fluxmeter

    DOEpatents

    Faybishenko, Boris A.

    2005-10-25

    A Vadose Zone Water Fluxmeter (WFM) or Direct Measurement WFM provides direct measurement of unsaturated water flow in the vadose zone. The fluxmeter is a cylindrical device that fits in a borehole or can be installed near the surface, or in pits, or in pile structures. The fluxmeter is primarily a combination of tensiometers and a porous element or plate in a water cell that is used for water injection or extraction under field conditions. The same water pressure measured outside and inside of the soil sheltered by the lower cylinder of the fluxmeter indicates that the water flux through the lower cylinder is similar to the water flux in the surrounding soil. The fluxmeter provides direct measurement of the water flow rate in the unsaturated soils and then determines the water flux, i.e. the water flow rate per unit area.

  10. Trojans in habitable zones.

    PubMed

    Schwarz, Richard; Pilat-Lohinger, Elke; Dvorak, Rudolf; Erdi, Balint; Sándor, Zsolt

    2005-10-01

    With the aid of numerical experiments we examined the dynamical stability of fictitious terrestrial planets in 1:1 mean motion resonance with Jovian-like planets of extrasolar planetary systems. In our stability study of the so-called "Trojan" planets in the habitable zone, we used the restricted three-body problem with different mass ratios of the primary bodies. The application of the three-body problem showed that even massive Trojan planets can be stable in the 1:1 mean motion resonance. From the 117 extrasolar planetary systems only 11 systems were found with one giant planet in the habitable zone. Out of this sample set we chose four planetary systems--HD17051, HD27442, HD28185, and HD108874--for further investigation. To study the orbital behavior of the stable zone in the different systems, we used direct numerical computations (Lie Integration Method) that allowed us to determine the escape times and the maximum eccentricity of the fictitious "Trojan planets." PMID:16225431

  11. Radiant zone heated particulate filter

    DOEpatents

    Gonze, Eugene V [Pinckney, MI

    2011-12-27

    A system includes a particulate matter (PM) filter including an upstream end for receiving exhaust gas and a downstream end. A radiant zoned heater includes N zones, where N is an integer greater than one, wherein each of the N zones includes M sub-zones, where M is an integer greater than or equal to one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones, restricts exhaust gas flow in a portion of the PM filter that corresponds to the selected one of the N zones, and deactivates non-selected ones of the N zones.

  12. 33 CFR 110.230 - Anchorages, Captain of the Port Puget Sound Zone, WA.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... citations affecting § 110.230, see the List of CFR Sections Affected, which appears in the Finding Aids... Puget Sound Zone, WA. 110.230 Section 110.230 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Port Puget Sound Zone, WA. (a) Anchorage grounds. All coordinates are expressed in North American...

  13. 33 CFR 110.230 - Anchorages, Captain of the Port Puget Sound Zone, WA.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... citations affecting § 110.230, see the List of CFR Sections Affected, which appears in the Finding Aids... Puget Sound Zone, WA. 110.230 Section 110.230 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Port Puget Sound Zone, WA. (a) Anchorage grounds. All coordinates are expressed in North American...

  14. Haz-Mat Refresher: Chemical Precautions

    ERIC Educational Resources Information Center

    Caliendo, Louis A.

    2012-01-01

    It is important that first responders remain aware of the possible hazards resulting from chemical accidents or the intentional use of chemicals in destructive devices. Chemical components can be utilized in the manufacturing of improvised explosive devices (IEDs), can enhance the effect of a more conventional device, or can pose hazards based on…

  15. High-power picosecond laser drilling/machining of carbon fibre-reinforced polymer (CFRP) composites

    NASA Astrophysics Data System (ADS)

    Salama, A.; Li, L.; Mativenga, P.; Sabli, A.

    2016-02-01

    The large differences in physical and thermal properties of the carbon fibre-reinforced polymer (CFRP) composite constituents make laser machining of this material challenging. An extended heat-affected zone (HAZ) often occurs. The availability of ultrashort laser pulse sources such as picosecond lasers makes it possible to improve the laser machining quality of these materials. This paper reports an investigation on the drilling and machining of CFRP composites using a state-of-the-art 400 W picosecond laser system. Small HAZs (<25 µm) were obtained on the entry side of 6-mm-diameter hole drilled on sample of 6 mm thickness, whereas no HAZ was seen below the top surface on the cut surfaces. Multiple ring material removal strategy was used. Furthermore, the effect of laser processing parameters such as laser power, scanning speed and repetition rate on HAZ sizes and ablation depth was investigated.

  16. On post-weld heat treatment cracking in tig welded superalloy ATI 718Plus

    NASA Astrophysics Data System (ADS)

    Asala, G.; Ojo, O. A.

    The susceptibility of heat affected zone (HAZ) to cracking in Tungsten Inert Gas (TIG) welded Allvac 718Plus superalloy during post-weld heat treatment (PWHT) was studied. Contrary to the previously reported case of low heat input electron beam welded Allvac 718Plus, where HAZ cracking occurred during PWHT, the TIG welded alloy is crack-free after PWHT, notwithstanding the presence of similar micro-constituents that caused cracking in the low input weld. Accordingly, the formation of brittle HAZ intergranular micro-constituents may not be a sufficient factor to determine cracking propensity, the extent of heat input during welding may be another major factor that influences HAZ cracking during PWHT of the aerospace superalloy Allvac 718Plus.

  17. Smartphones and Time Zones

    NASA Astrophysics Data System (ADS)

    Baird, William; Secrest, Jeffery; Padgett, Clifford; Johnson, Wayne; Hagrelius, Claire

    2016-09-01

    Using the Sun to tell time is an ancient idea, but we can take advantage of modern technology to bring it into the 21st century for students in astronomy, physics, or physical science classes. We have employed smartphones, Google Earth, and 3D printing to find the moment of local noon at two widely separated locations. By reviewing GPS time-stamped photos from each place, we are able to illustrate that local noon is longitude-dependent and therefore explain the need for time zones.

  18. Saturated Zone Colloid Transport

    SciTech Connect

    H. S. Viswanathan

    2004-10-07

    This scientific analysis provides retardation factors for colloids transporting in the saturated zone (SZ) and the unsaturated zone (UZ). These retardation factors represent the reversible chemical and physical filtration of colloids in the SZ. The value of the colloid retardation factor, R{sub col} is dependent on several factors, such as colloid size, colloid type, and geochemical conditions (e.g., pH, Eh, and ionic strength). These factors are folded into the distributions of R{sub col} that have been developed from field and experimental data collected under varying geochemical conditions with different colloid types and sizes. Attachment rate constants, k{sub att}, and detachment rate constants, k{sub det}, of colloids to the fracture surface have been measured for the fractured volcanics, and separate R{sub col} uncertainty distributions have been developed for attachment and detachment to clastic material and mineral grains in the alluvium. Radionuclides such as plutonium and americium sorb mostly (90 to 99 percent) irreversibly to colloids (BSC 2004 [DIRS 170025], Section 6.3.3.2). The colloid retardation factors developed in this analysis are needed to simulate the transport of radionuclides that are irreversibly sorbed onto colloids; this transport is discussed in the model report ''Site-Scale Saturated Zone Transport'' (BSC 2004 [DIRS 170036]). Although it is not exclusive to any particular radionuclide release scenario, this scientific analysis especially addresses those scenarios pertaining to evidence from waste-degradation experiments, which indicate that plutonium and americium may be irreversibly attached to colloids for the time scales of interest. A section of this report will also discuss the validity of using microspheres as analogs to colloids in some of the lab and field experiments used to obtain the colloid retardation factors. In addition, a small fraction of colloids travels with the groundwater without any significant retardation

  19. Liquid zone seal

    DOEpatents

    Klebanoff, Leonard E.

    2001-01-01

    A seal assembly that provides a means for establishing multiple pressure zones within a system. The seal assembly combines a plate extending from the inner wall of a housing or inner enclosure that intersects with and is immersed in the fluid contained in a well formed in a tray contained within the enclosure. The fluid is a low vapor pressure oil, chemically inert and oxidation resistant. The use of a fluid as the sealing component provides a seal that is self-healing and mechanically robust not subject to normal mechanical wear, breakage, and formation of cracks or pinholes and decouples external mechanical vibrations from internal structural members.

  20. Spreading dead zones and consequences for marine ecosystems.

    PubMed

    Diaz, Robert J; Rosenberg, Rutger

    2008-08-15

    Dead zones in the coastal oceans have spread exponentially since the 1960s and have serious consequences for ecosystem functioning. The formation of dead zones has been exacerbated by the increase in primary production and consequent worldwide coastal eutrophication fueled by riverine runoff of fertilizers and the burning of fossil fuels. Enhanced primary production results in an accumulation of particulate organic matter, which encourages microbial activity and the consumption of dissolved oxygen in bottom waters. Dead zones have now been reported from more than 400 systems, affecting a total area of more than 245,000 square kilometers, and are probably a key stressor on marine ecosystems.

  1. Impact of contact lens zone geometry and ocular optics on bifocal retinal image quality

    PubMed Central

    Bradley, Arthur; Nam, Jayoung; Xu, Renfeng; Harman, Leslie; Thibos, Larry

    2014-01-01

    Purpose To examine the separate and combined influences of zone geometry, pupil size, diffraction, apodisation and spherical aberration on the optical performance of concentric zonal bifocals. Methods Zonal bifocal pupil functions representing eye + ophthalmic correction were defined by interleaving wavefronts from separate optical zones of the bifocal. A two-zone design (a central circular inner zone surrounded by an annular outer-zone which is bounded by the pupil) and a five-zone design (a central small circular zone surrounded by four concentric annuli) were configured with programmable zone geometry, wavefront phase and pupil transmission characteristics. Using computational methods, we examined the effects of diffraction, Stiles Crawford apodisation, pupil size and spherical aberration on optical transfer functions for different target distances. Results Apodisation alters the relative weighting of each zone, and thus the balance of near and distance optical quality. When spherical aberration is included, the effective distance correction, add power and image quality depend on zone-geometry and Stiles Crawford Effect apodisation. When the outer zone width is narrow, diffraction limits the available image contrast when focused, but as pupil dilates and outer zone width increases, aberrations will limit the best achievable image quality. With two-zone designs, balancing near and distance image quality is not achieved with equal area inner and outer zones. With significant levels of spherical aberration, multi-zone designs effectively become multifocals. Conclusion Wave optics and pupil varying ocular optics significantly affect the imaging capabilities of different optical zones of concentric bifocals. With two-zone bifocal designs, diffraction, pupil apodisation spherical aberration, and zone size influence both the effective add power and the pupil size required to balance near and distance image quality. Five-zone bifocal designs achieve a high degree of

  2. Earthquake ruptures modulated by waves in damaged fault zones

    NASA Astrophysics Data System (ADS)

    Huang, Yihe; Ampuero, Jean-Paul; Helmberger, Don V.

    2014-04-01

    Faults are usually surrounded by damaged zones of lower elastic moduli and seismic wave velocities than their host rocks. If the interface between the damaged rocks and host rocks is sharp enough, earthquakes happening inside the fault zone generate reflected waves and head waves, which can interact with earthquake ruptures and modulate rupture properties such as rupture speed, slip rate, and rise time. We find through 2-D dynamic rupture simulations the following: (1) Reflected waves can induce multiple slip pulses. The rise time of the primary pulse is controlled by fault zone properties, rather than by frictional properties. (2) Head waves can cause oscillations of rupture speed and, in a certain range of fault zone widths, a permanent transition to supershear rupture with speeds that would be unstable in homogeneous media. (3) Large attenuation smears the slip rate function and delays the initial acceleration of rupture speed but does not affect significantly the rise time or the period of rupture speed oscillations. (4) Fault zones cause a rotation of the background stress field and can induce plastic deformations on both extensional and compressional sides of the fault. The plastic deformations are accumulated both inside and outside the fault zone, which indicates a correlation between fault zone development and repeating ruptures. Spatially periodic patterns of plastic deformations are formed due to oscillating rupture speed, which may leave a permanent signature in the geological record. Our results indicate that damaged fault zones with sharp boundaries promote multiple slip pulses and supershear ruptures.

  3. Breathing zone air sampler

    DOEpatents

    Tobin, John

    1989-01-01

    A sampling apparatus is provided which comprises a sampler for sampling air in the breathing zone of a wearer of the apparatus and a support for the sampler preferably in the form of a pair of eyeglasses. The sampler comprises a sampling assembly supported on the frame of the eyeglasses and including a pair of sample transport tubes which are suspended, in use, centrally of the frame so as to be disposed on opposite sides of the nose of the wearer and which each include an inlet therein that, in use, is disposed adjacent to a respective nostril of the nose of the wearer. A filter holder connected to sample transport tubes supports a removable filter for filtering out particulate material in the air sampled by the apparatus. The sample apparatus is connected to a pump for drawing air into the apparatus through the tube inlets so that the air passes through the filter.

  4. The zone diet and athletic performance.

    PubMed

    Cheuvront, S N

    1999-04-01

    The Zone diet is the latest eating regimen marketed to improve athletic performance by opposing traditional high carbohydrate sports diets. The 40/30/30 diet is centred primarily on protein intake (1.8 to 2.2 g/kg fat free mass; i.e. total bodyweight-fat weight) and promises a change in the body's insulin to glucagon ratio through its macronutrient alterations. Changes in the existing hormonal milieu are said to result in the production of more vasoactive eicosanoids, thus allowing greater oxygen delivery to exercising muscle. This favourable condition, known as the Zone, is anecdotally reported to benefit even the most elite endurance athletes. Applying the Zone's suggested protein needs and macronutrient distributions in practice, it is clear that it is a low carbohydrate diet by both relative and absolute standards, as well as calorie deficient by any standard. Reliable and abundant peer reviewed literature is in opposition to the suggestion that such a diet can support competitive athletic endeavours, much less improve them. The notion that a 40/30/30 diet can alter the pancreatic hormone response in favour of glucagon is also unfounded. The Zone is a mixed diet and not likely to affect pancreatic hormone release in the same way individual nutrients can. Although the postprandial insulin response is reduced when comparing a 40% with a 60% carbohydrate diet, it is still a sufficient stimulus to offset the lipolytic effects of glucagon. Many of the promised benefits of the Zone are based on selective information regarding hormonal influences on eicosanoid biology. Contradictory information is conveniently left out. The principle of vasodilating muscle arterioles by altering eicosanoid production is notably correct in theory. However, what little human evidence is available does not support any significant contribution of eicosanoids to active muscle vasodilation. In fact, the key eicosanoid reportedly produced in the Zone and responsible for improved muscle

  5. 15 CFR 921.4 - Relationship to other provisions of the Coastal Zone Management Act, and to the Marine Protection...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the Coastal Zone Management Act, and to the Marine Protection, Research and Sanctuaries Act. 921.4... provisions of the Coastal Zone Management Act, and to the Marine Protection, Research and Sanctuaries Act. (a... affecting the state's coastal zone, must be undertaken in a manner consistent to the maximum...

  6. 15 CFR 921.4 - Relationship to other provisions of the Coastal Zone Management Act, and to the Marine Protection...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the Coastal Zone Management Act, and to the Marine Protection, Research and Sanctuaries Act. 921.4... provisions of the Coastal Zone Management Act, and to the Marine Protection, Research and Sanctuaries Act. (a... affecting the state's coastal zone, must be undertaken in a manner consistent to the maximum...

  7. 15 CFR 921.4 - Relationship to other provisions of the Coastal Zone Management Act, and to the Marine Protection...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... the Coastal Zone Management Act, and to the Marine Protection, Research and Sanctuaries Act. 921.4... provisions of the Coastal Zone Management Act, and to the Marine Protection, Research and Sanctuaries Act. (a... affecting the state's coastal zone, must be undertaken in a manner consistent to the maximum...

  8. 15 CFR 921.4 - Relationship to other provisions of the Coastal Zone Management Act, and to the Marine Protection...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the Coastal Zone Management Act, and to the Marine Protection, Research and Sanctuaries Act. 921.4... provisions of the Coastal Zone Management Act, and to the Marine Protection, Research and Sanctuaries Act. (a... affecting the state's coastal zone, must be undertaken in a manner consistent to the maximum...

  9. 15 CFR 921.4 - Relationship to other provisions of the Coastal Zone Management Act, and to the Marine Protection...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the Coastal Zone Management Act, and to the Marine Protection, Research and Sanctuaries Act. 921.4... provisions of the Coastal Zone Management Act, and to the Marine Protection, Research and Sanctuaries Act. (a... affecting the state's coastal zone, must be undertaken in a manner consistent to the maximum...

  10. Zone refining of plutonium metal

    SciTech Connect

    Blau, M.S.

    1994-08-01

    The zone refining process was applied to Pu metal containing known amounts of impurities. Rod specimens of plutonium metal were melted into and contained in tantalum boats, each of which was passed horizontally through a three-turn, high-frequency coil in such a manner as to cause a narrow molten zone to pass through the Pu metal rod 10 times. The impurity elements Co, Cr, Fe, Ni, Np, U were found to move in the same direction as the molten zone as predicted by binary phase diagrams. The elements Al, Am, and Ga moved in the opposite direction of the molten zone as predicted by binary phase diagrams. As the impurity alloy was zone refined, {delta}-phase plutonium metal crystals were produced. The first few zone refining passes were more effective than each later pass because an oxide layer formed on the rod surface. There was no clear evidence of better impurity movement at the slower zone refining speed. Also, constant or variable coil power appeared to have no effect on impurity movement during a single run (10 passes). This experiment was the first step to developing a zone refining process for plutonium metal.

  11. Detecting livestock production zones.

    PubMed

    Grisi-Filho, J H H; Amaku, M; Ferreira, F; Dias, R A; Neto, J S Ferreira; Negreiros, R L; Ossada, R

    2013-07-01

    Communities are sets of nodes that are related in an important way, most likely sharing common properties and/or playing similar roles within a network. Unraveling a network structure, and hence the trade preferences and pathways, could be useful to a researcher or a decision maker. We implemented a community detection algorithm to find livestock communities, which is consistent with the definition of a livestock production zone, assuming that a community is a group of farm premises in which an animal is more likely to stay during its lifetime than expected by chance. We applied this algorithm to the network of animal movements within the state of Mato Grosso for 2007. This database holds information concerning 87,899 premises and 521,431 movements throughout the year, totaling 15,844,779 animals moved. The community detection algorithm achieved a network partition that shows a clear geographical and commercial pattern, two crucial features for preventive veterinary medicine applications; this algorithm provides also a meaningful interpretation to trade networks where links emerge based on trader node choices.

  12. Capillary zone electrophoresis

    SciTech Connect

    Jorgenson, J.W.; Lukacs, K.D.

    1983-10-21

    Zone electrophoresis in capillaries is a technique complementary to electrophoresis in supporting media, and each approach has its own particular advantages. Efficient heat transfer from small-diameter capillaries permits use of unusually high voltages, resulting in both high resolution and rapid analysis. Capillaries also seem well suited for automation. Our present electromigration injection technique is relatively straightforward and should be simple to automate. Capillaries are reusable, which is an advantage over gels. On-line electronic detection permits good quantification, further enhancing possibilities for fully automatic operation. The greatest obstacle to further development and utilization of capillaries is the requirement of extremely sensitive detectors, and more types of detectors with higher sensitivity are greatly needed. A better understanding of capillary surface modification will also be important, both for improved capillary surface deactivation and for better control over electroosmotic flow. Capillaries should provide an ideal system in which to explore nonaqueous separation media. The prospects for nonaqueous media in electrophoresis are similar to those in electrochemistry, and capillaries should prove an excellent system in which to begin their study. 18 refs., 8 figs.

  13. Influence of the Amlia fracture zone on the evolution of the Aleutian Terrace forearc basin, central Aleutian subduction zone

    USGS Publications Warehouse

    Ryan, Holly F.; Draut, Amy E.; Keranen, Katie M.; Scholl, David W.

    2012-01-01

    During Pliocene to Quaternary time, the central Aleutian forearc basin evolved in response to a combination of tectonic and climatic factors. Initially, along-trench transport of sediment and accretion of a frontal prism created the accommodation space to allow forearc basin deposition. Transport of sufficient sediment to overtop the bathymetrically high Amlia fracture zone and reach the central Aleutian arc began with glaciation of continental Alaska in the Pliocene. As the obliquely subducting Amlia fracture zone swept along the central Aleutian arc, it further affected the structural evolution of the forearc basins. The subduction of the Amlia fracture zone resulted in basin inversion and loss of accommodation space east of the migrating fracture zone. Conversely, west of Amlia fracture zone, accommodation space increased arcward of a large outer-arc high that formed, in part, by a thickening of arc basement. This difference in deformation is interpreted to be the result of a variation in interplate coupling across the Amlia fracture zone that was facilitated by increasing subduction obliquity, a change in orientation of the subducting Amlia fracture zone, and late Quaternary intensification of glaciation. The change in coupling is manifested by a possible tear in the subducting slab along the Amlia fracture zone. Differences in coupling across the Amlia fracture zone have important implications for the location of maximum slip during future great earthquakes. In addition, shaking during a great earthquake could trigger large mass failures of the summit platform, as evidenced by the presence of thick mass transport deposits of primarily Quaternary age that are found in the forearc basin west of the Amlia fracture zone.

  14. 49 CFR 71.8 - Mountain zone.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  15. 49 CFR 71.8 - Mountain zone.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  16. 49 CFR 71.8 - Mountain zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  17. 49 CFR 71.8 - Mountain zone.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  18. 49 CFR 71.8 - Mountain zone.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  19. Utilization of management zones for reniform nematodes in cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability to record measurements of soil electrical conductivity (EC) and field elevation at precise and closely-spaced GPS coordinates allows us to define nematode management zones based on field physical characteristics which may affect reniform nematode (Rotylenchulus reniformis) population lev...

  20. 50 CFR 20.108 - Nontoxic shot zones.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Annual Seasons, Limits, and Shooting Hours Schedules § 20.108... United States, are designated for the purpose of § 20.21(j) as nontoxic shot zones for hunting waterfowl... or coots, that are affected by reason of being included in aggregate bags and concurrent seasons....

  1. 50 CFR 20.108 - Nontoxic shot zones.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Annual Seasons, Limits, and Shooting Hours Schedules § 20.108... United States, are designated for the purpose of § 20.21(j) as nontoxic shot zones for hunting waterfowl... or coots, that are affected by reason of being included in aggregate bags and concurrent seasons....

  2. 50 CFR 20.108 - Nontoxic shot zones.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Annual Seasons, Limits, and Shooting Hours Schedules § 20.108... United States, are designated for the purpose of § 20.21(j) as nontoxic shot zones for hunting waterfowl... or coots, that are affected by reason of being included in aggregate bags and concurrent seasons....

  3. 50 CFR 20.108 - Nontoxic shot zones.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Annual Seasons, Limits, and Shooting Hours Schedules § 20.108... United States, are designated for the purpose of § 20.21(j) as nontoxic shot zones for hunting waterfowl... or coots, that are affected by reason of being included in aggregate bags and concurrent seasons....

  4. 50 CFR 20.108 - Nontoxic shot zones.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Annual Seasons, Limits, and Shooting Hours Schedules § 20.108... United States, are designated for the purpose of § 20.21(j) as nontoxic shot zones for hunting waterfowl... or coots, that are affected by reason of being included in aggregate bags and concurrent seasons....

  5. Capture zones for simple aquifers

    USGS Publications Warehouse

    McElwee, Carl D.

    1991-01-01

    Capture zones showing the area influenced by a well within a certain time are useful for both aquifer protection and cleanup. If hydrodynamic dispersion is neglected, a deterministic curve defines the capture zone. Analytical expressions for the capture zones can be derived for simple aquifers. However, the capture zone equations are transcendental and cannot be explicitly solved for the coordinates of the capture zone boundary. Fortunately, an iterative scheme allows the solution to proceed quickly and efficiently even on a modest personal computer. Three forms of the analytical solution must be used in an iterative scheme to cover the entire region of interest, after the extreme values of the x coordinate are determined by an iterative solution. The resulting solution is a discrete one, and usually 100-1000 intervals along the x-axis are necessary for a smooth definition of the capture zone. The presented program is written in FORTRAN and has been used in a variety of computing environments. No graphics capability is included with the program; it is assumed the user has access to a commercial package. The superposition of capture zones for multiple wells is expected to be satisfactory if the spacing is not too close. Because this program deals with simple aquifers, the results rarely will be the final word in a real application.

  6. Nutrient cycling in bedform induced hyporheic zones

    NASA Astrophysics Data System (ADS)

    Bardini, L.; Boano, F.; Cardenas, M. B.; Revelli, R.; Ridolfi, L.

    2012-05-01

    The hyporheic zone is an ecotone connecting the stream and groundwater ecosystem that plays a significant role for stream biogeochemistry. Water exchange across the stream-sediment interface and biogeochemical reactions in the streambed concur to affect subsurface solute concentrations and eventually nutrient cycling in the fluvial corridor. In this paper we investigate the interplay of hydrological and biogeochemical processes in a duned streambed and their effect on spatial distribution of solutes. We employ a numerical model to simulate the turbulent water flow and the pressure distribution over the dunes, and then to evaluate the flow field and the biogeochemical reactions in the hyporheic sediments. Sensitivity analyses are performed to analyze the influence of hydrological and chemical properties of the system on solute reaction rates. The results demonstrate the effect of stream velocity and sediment permeability on the chemical zonation. Changing sediment permeability as well as stream velocity directly affects the nutrient supply and the residence times in the streambed, thus controlling the reaction rates under the dune. Stream-water quality is also shown to influence the reactive behavior of the sediments. In particular, the availability of dissolved organic carbon determines whether the streambed acts as a net sink or source of nitrate. This study represents a step towards a better understanding of the complex interactions between hydrodynamical and biogeochemical processes in the hyporheic zone.

  7. Improvement in Laser Weldability of INCONEL 738 Superalloy through Microstructural Modification

    NASA Astrophysics Data System (ADS)

    Egbewande, A. T.; Zhang, H. R.; Sidhu, R. K.; Ojo, O. A.

    2009-11-01

    Microstructural study of laser-beam-welded IN 738 superalloy was carefully performed to better understand the causes of heat-affected zone (HAZ) cracking and to determine an improved approach of alleviating the weldability problem. The HAZ cracks in the alloy were intergranular liquation cracks that resulted from the liquation reaction of both secondary solidification products (MC carbides and γ- γ' eutectic) and solid-state reaction products ( γ' particles) present in the preweld material. In contrast to the expectation based on Chadwick’s equation, a reduction of grain boundary liquid film thickness did not produce a decrease in HAZ cracking owing to increased base alloy hardness that accompanied a preweld heat treatment designed to reduce the intergranular liquation. Moreover, a major factor limiting the effectiveness of an existing preweld heat treatment with low base alloy hardness in reducing HAZ cracking was found to be the formation of intergranular M5B3 boride particles during the heat treatment. These borides can widen the HAZ brittle temperature range (BTR) during weld cooling and increase the propensity for cracking. Based on the results, a new preweld heat treatment that induces a moderate hardness and precludes grain boundary boride formation was found and was shown to produce a significant reduction in HAZ cracking in the welded alloy compared to the most effective pre-existing preweld heat treatment.

  8. CHAOTIC ZONES AROUND GRAVITATING BINARIES

    SciTech Connect

    Shevchenko, Ivan I.

    2015-01-20

    The extent of the continuous zone of chaotic orbits of a small-mass tertiary around a system of two gravitationally bound primaries of comparable masses (a binary star, a binary black hole, a binary asteroid, etc.) is estimated analytically, as a function of the tertiary's orbital eccentricity. The separatrix map theory is used to demonstrate that the central continuous chaos zone emerges (above a threshold in the primaries' mass ratio) due to overlapping of the orbital resonances corresponding to the integer ratios p:1 between the tertiary and the central binary periods. In this zone, the unlimited chaotic orbital diffusion of the tertiary takes place, up to its ejection from the system. The primaries' mass ratio, above which such a chaotic zone is universally present at all initial eccentricities of the tertiary, is estimated. The diversity of the observed orbital configurations of biplanetary and circumbinary exosystems is shown to be in accord with the existence of the primaries' mass parameter threshold.

  9. In situ vadose zone bioremediation.

    PubMed

    Höhener, Patrick; Ponsin, Violaine

    2014-06-01

    Contamination of the vadose zone with various pollutants is a world-wide problem, and often technical or economic constraints impose remediation without excavation. In situ bioremediation in the vadose zone by bioventing has become a standard remediation technology for light spilled petroleum products. In this review, focus is given on new in situ bioremediation strategies in the vadose zone targeting a variety of other pollutants such as perchlorate, nitrate, uranium, chromium, halogenated solvents, explosives and pesticides. The techniques for biostimulation of either oxidative or reductive degradation pathways are presented, and biotransformations to immobile pollutants are discussed in cases of non-degradable pollutants. Furthermore, research on natural attenuation in the vadose zone is presented.

  10. Cohesive Zone Model User Element

    2007-04-17

    Cohesive Zone Model User Element (CZM UEL) is an implementation of a Cohesive Zone Model as an element for use in finite element simulations. CZM UEL computes a nodal force vector and stiffness matrix from a vector of nodal displacements. It is designed for structural analysts using finite element software to predict crack initiation, crack propagation, and the effect of a crack on the rest of a structure.

  11. 78 FR 27032 - Safety Zones; Annual Events in the Captain of the Port Detroit Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-09

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zones; Annual Events in the Captain of the Port Detroit Zone... enforce various safety zones for annual marine events in the Captain of the Port Detroit zone from May 24... 165.941, Safety Zones; Annual Events in the Captain of the Port Detroit Zone, at the following...

  12. 76 FR 22033 - Safety Zone; Red River Safety Zone, Red River, MN

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AAOO Safety Zone; Red River Safety Zone, Red River, MN AGENCY... Safety Unit Duluth, MN is establishing a temporary safety zone on the Red River, MN. This safety zone is...-0263 to read as follows: Sec. 165.T09-0263 Safety zone; Red River Safety Zone, Red River, MN....

  13. Zoning, equity, and public health.

    PubMed Central

    Maantay, J

    2001-01-01

    Zoning, the most prevalent land use planning tool in the United States, has substantial implications for equity and public health. Zoning determines where various categories of land use may go, thereby influencing the location of resulting environmental and health impacts. Industrially zoned areas permit noxious land uses and typically carry higher environmental burdens than other areas. Using New York City as a case study, the author shows that industrial zones have large residential populations within them or nearby. Noxious uses tend to be concentrated in poor and minority industrial neighborhoods because more affluent industrial areas and those with lower minority populations are rezoned for other uses, and industrial zones in poorer neighborhoods are expanded. Zoning policies, therefore, can have adverse impacts on public health and equity. The location of noxious uses and the pollution they generate have ramifications for global public health and equity; these uses have been concentrated in the world's poorer places as well as in poorer places within more affluent countries. Planners, policymakers, and public health professionals must collaborate on a worldwide basis to address these equity, health, and land use planning problems. PMID:11441726

  14. The global aftershock zone

    USGS Publications Warehouse

    Parsons, Thomas E.; Margaret Segou,; Warner Marzocchi,

    2014-01-01

    The aftershock zone of each large (M ≥ 7) earthquake extends throughout the shallows of planet Earth. Most aftershocks cluster near the mainshock rupture, but earthquakes send out shivers in the form of seismic waves, and these temporary distortions are large enough to trigger other earthquakes at global range. The aftershocks that happen at great distance from their mainshock are often superposed onto already seismically active regions, making them difficult to detect and understand. From a hazard perspective we are concerned that this dynamic process might encourage other high magnitude earthquakes, and wonder if a global alarm state is warranted after every large mainshock. From an earthquake process perspective we are curious about the physics of earthquake triggering across the magnitude spectrum. In this review we build upon past studies that examined the combined global response to mainshocks. Such compilations demonstrate significant rate increases during, and immediately after (~ 45 min) M > 7.0 mainshocks in all tectonic settings and ranges. However, it is difficult to find strong evidence for M > 5 rate increases during the passage of surface waves in combined global catalogs. On the other hand, recently published studies of individual large mainshocks associate M > 5 triggering at global range that is delayed by hours to days after surface wave arrivals. The longer the delay between mainshock and global aftershock, the more difficult it is to establish causation. To address these questions, we review the response to 260 M ≥ 7.0 shallow (Z ≤ 50 km) mainshocks in 21 global regions with local seismograph networks. In this way we can examine the detailed temporal and spatial response, or lack thereof, during passing seismic waves, and over the 24 h period after their passing. We see an array of responses that can involve immediate and widespread seismicity outbreaks, delayed and localized earthquake clusters, to no response at all. About 50% of the

  15. Robotic comfort zones

    NASA Astrophysics Data System (ADS)

    Likhachev, Maxim; Arkin, Ronald C.

    2000-10-01

    The paper investigates how the psychological notion of comfort can be useful in the design of robotic systems. A review of the existing study of human comfort, especially regarding its presence in infants, is conducted with the goal being to determine the relevant characteristics for mapping it onto the robotics domain. Focus is place on the identification of the salient features in the environment that affect the comfort level. Factors involved include current state familiarity, working conditions, the amount and location of available resources, etc. As part of our newly developed comfort function theory, the notion of an object as a psychological attachment for a robot is also introduced, as espoused in Bowlby's theory of attachment. The output space of the comfort function and its dependency on the comfort level are analyzed. The results of the derivation of this comfort function are then presented in terms of the impact they have on robotic behavior. Justification for the use of the comfort function are then presented in terms of the impact they have on robotic behavior. Justification for the use of the comfort function in the domain of robotics is presented with relevance for real-world operations. Also, a transformation of the theoretical discussion into a mathematical framework suitable for implementation within a behavior-based control system is presented. The paper concludes with results of simulation studies and real robot experiments using the derived comfort function.

  16. Fracture process zone in granite

    USGS Publications Warehouse

    Zang, A.; Wagner, F.C.; Stanchits, S.; Janssen, C.; Dresen, G.

    2000-01-01

    In uniaxial compression tests performed on Aue granite cores (diameter 50 mm, length 100 mm), a steel loading plate was used to induce the formation of a discrete shear fracture. A zone of distributed microcracks surrounds the tip of the propagating fracture. This process zone is imaged by locating acoustic emission events using 12 piezoceramic sensors attached to the samples. Propagation velocity of the process zone is varied by using the rate of acoustic emissions to control the applied axial force. The resulting velocities range from 2 mm/s in displacement-controlled tests to 2 ??m/s in tests controlled by acoustic emission rate. Wave velocities and amplitudes are monitored during fault formation. P waves transmitted through the approaching process zone show a drop in amplitude of 26 dB, and ultrasonic velocities are reduced by 10%. The width of the process zone is ???9 times the grain diameter inferred from acoustic data but is only 2 times the grain size from optical crack inspection. The process zone of fast propagating fractures is wider than for slow ones. The density of microcracks and acoustic emissions increases approaching the main fracture. Shear displacement scales linearly with fracture length. Fault plane solutions from acoustic events show similar orientation of nodal planes on both sides of the shear fracture. The ratio of the process zone width to the fault length in Aue granite ranges from 0.01 to 0.1 inferred from crack data and acoustic emissions, respectively. The fracture surface energy is estimated from microstructure analysis to be ???2 J. A lower bound estimate for the energy dissipated by acoustic events is 0.1 J. Copyright 2000 by the American Geophysical Union.

  17. X-ray Microdiffraction and EBSD Study of FSP Induced Structural/Phase Transitions in a Ni-based Superalloy

    SciTech Connect

    Barabash, Oleg M; Barabash, Rozaliya; Ice, Gene E; Feng, Zhili; Gandy, Dr. David

    2009-01-01

    Severe plastic deformation during Friction Stir Processing (FSP) of an IN738 Ni-based superalloy was studied by means of X-ray polychromatic microdiffraction, EBSD, scanning electron and optical microscopies. Modeling of the physical properties and phase composition was also performed. Several distinct zones are formed during FSP including a stir zone (SZ), a thermal-mechanical affected zone (TMAZ) and a heat affected zone (HAZ). Each zone has distinct microstructure after FSP. The initial dendrite structure is preserved in the HAZ, while strengthening ??-phase particles partially dissolve and coagulate. Plastic deformation of the base material dendrites takes place in the TMAZ and a large number of geometrically necessary dislocations are formed. The extent of deformation increases toward the SZ and the dendrite structure is completely destroyed in the SZ and replaced by a fine submicrocrystalline microstructure.

  18. 33 CFR 165.20 - Safety zones.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Safety zones. 165.20 Section 165... WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Safety Zones § 165.20 Safety zones. A Safety Zone is a water area, shore area, or water and shore area to which, for safety or...

  19. 33 CFR 165.20 - Safety zones.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Safety zones. 165.20 Section 165... WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Safety Zones § 165.20 Safety zones. A Safety Zone is a water area, shore area, or water and shore area to which, for safety or...

  20. 33 CFR 165.20 - Safety zones.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Safety zones. 165.20 Section 165... WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Safety Zones § 165.20 Safety zones. A Safety Zone is a water area, shore area, or water and shore area to which, for safety or...

  1. 33 CFR 165.20 - Safety zones.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety zones. 165.20 Section 165... WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Safety Zones § 165.20 Safety zones. A Safety Zone is a water area, shore area, or water and shore area to which, for safety or...

  2. 33 CFR 165.20 - Safety zones.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Safety zones. 165.20 Section 165... WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Safety Zones § 165.20 Safety zones. A Safety Zone is a water area, shore area, or water and shore area to which, for safety or...

  3. State Enterprise Zone Programs: Have They Worked?

    ERIC Educational Resources Information Center

    Peters, Alan H.; Fisher, Peter S.

    The effectiveness of state enterprise zone programs was examined by using a hypothetical-firm model called the Tax and Incentives Model-Enterprise Zones (TAIM-ez) model to analyze the value of enterprise zone incentives to businesses across the United States and especially in the 13 states that had substantial enterprise zone programs by 1990. The…

  4. 47 CFR 5.313 - Innovation zones.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Innovation zones. 5.313 Section 5.313... Licenses § 5.313 Innovation zones. (a) An innovation zone is a specified geographic location with pre... own motion or in response to a request from the public. Innovation zones will be announced via...

  5. 47 CFR 5.313 - Innovation zones.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Innovation zones. 5.313 Section 5.313... Licenses § 5.313 Innovation zones. (a) An innovation zone is a specified geographic location with pre... own motion or in response to a request from the public. Innovation zones will be announced via...

  6. 47 CFR 73.205 - Zones.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Zones. 73.205 Section 73.205 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES FM Broadcast Stations § 73.205 Zones. For the purpose of allotments and assignments, the United States is divided into three zones as follows: (a) Zone...

  7. 19 CFR 146.7 - Zone changes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Zone changes. 146.7 Section 146.7 Customs Duties U... (CONTINUED) FOREIGN TRADE ZONES General Provisions § 146.7 Zone changes. (a) Alteration of an activated area... operations performed in the zone are substantially changed; (3) the existing bond lacks good and...

  8. 19 CFR 146.7 - Zone changes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Zone changes. 146.7 Section 146.7 Customs Duties U... (CONTINUED) FOREIGN TRADE ZONES General Provisions § 146.7 Zone changes. (a) Alteration of an activated area... operations performed in the zone are substantially changed; (3) the existing bond lacks good and...

  9. 47 CFR 73.205 - Zones.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 4 2011-10-01 2011-10-01 false Zones. 73.205 Section 73.205 Telecommunication... Broadcast Stations § 73.205 Zones. For the purpose of allotments and assignments, the United States is divided into three zones as follows: (a) Zone I consists of that portion of the United States...

  10. 47 CFR 73.609 - Zones.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 4 2011-10-01 2011-10-01 false Zones. 73.609 Section 73.609 Telecommunication... Broadcast Stations § 73.609 Zones. (a) For the purpose of allotment and assignment, the United States is divided into three zones as follows: (1) Zone I consists of that portion of the United States...

  11. 47 CFR 73.205 - Zones.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Zones. 73.205 Section 73.205 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES FM Broadcast Stations § 73.205 Zones. For the purpose of allotments and assignments, the United States is divided into three zones as follows: (a) Zone...

  12. The genetics of nodal marginal zone lymphoma.

    PubMed

    Spina, Valeria; Khiabanian, Hossein; Messina, Monica; Monti, Sara; Cascione, Luciano; Bruscaggin, Alessio; Spaccarotella, Elisa; Holmes, Antony B; Arcaini, Luca; Lucioni, Marco; Tabbò, Fabrizio; Zairis, Sakellarios; Diop, Fary; Cerri, Michaela; Chiaretti, Sabina; Marasca, Roberto; Ponzoni, Maurilio; Deaglio, Silvia; Ramponi, Antonio; Tiacci, Enrico; Pasqualucci, Laura; Paulli, Marco; Falini, Brunangelo; Inghirami, Giorgio; Bertoni, Francesco; Foà, Robin; Rabadan, Raul; Gaidano, Gianluca; Rossi, Davide

    2016-09-01

    Nodal marginal zone lymphoma (NMZL) is a rare, indolent B-cell tumor that is distinguished from splenic marginal zone lymphoma (SMZL) by the different pattern of dissemination. NMZL still lacks distinct markers and remains orphan of specific cancer gene lesions. By combining whole-exome sequencing, targeted sequencing of tumor-related genes, whole-transcriptome sequencing, and high-resolution single nucleotide polymorphism array analysis, we aimed at disclosing the pathways that are molecularly deregulated in NMZL and we compare the molecular profile of NMZL with that of SMZL. These analyses identified a distinctive pattern of nonsilent somatic lesions in NMZL. In 35 NMZL patients, 41 genes were found recurrently affected in ≥3 (9%) cases, including highly prevalent molecular lesions of MLL2 (also known as KMT2D; 34%), PTPRD (20%), NOTCH2 (20%), and KLF2 (17%). Mutations of PTPRD, a receptor-type protein tyrosine phosphatase regulating cell growth, were enriched in NMZL across mature B-cell tumors, functionally caused the loss of the phosphatase activity of PTPRD, and were associated with cell-cycle transcriptional program deregulation and increased proliferation index in NMZL. Although NMZL shared with SMZL a common mutation profile, NMZL harbored PTPRD lesions that were otherwise absent in SMZL. Collectively, these findings provide new insights into the genetics of NMZL, identify PTPRD lesions as a novel marker for this lymphoma across mature B-cell tumors, and support the distinction of NMZL as an independent clinicopathologic entity within the current lymphoma classification.

  13. The genetics of nodal marginal zone lymphoma

    PubMed Central

    Spina, Valeria; Khiabanian, Hossein; Messina, Monica; Monti, Sara; Cascione, Luciano; Bruscaggin, Alessio; Spaccarotella, Elisa; Holmes, Antony B.; Arcaini, Luca; Lucioni, Marco; Tabbò, Fabrizio; Zairis, Sakellarios; Diop, Fary; Cerri, Michaela; Chiaretti, Sabina; Marasca, Roberto; Ponzoni, Maurilio; Deaglio, Silvia; Ramponi, Antonio; Tiacci, Enrico; Pasqualucci, Laura; Paulli, Marco; Falini, Brunangelo; Inghirami, Giorgio; Bertoni, Francesco; Foà, Robin; Rabadan, Raul; Gaidano, Gianluca

    2016-01-01

    Nodal marginal zone lymphoma (NMZL) is a rare, indolent B-cell tumor that is distinguished from splenic marginal zone lymphoma (SMZL) by the different pattern of dissemination. NMZL still lacks distinct markers and remains orphan of specific cancer gene lesions. By combining whole-exome sequencing, targeted sequencing of tumor-related genes, whole-transcriptome sequencing, and high-resolution single nucleotide polymorphism array analysis, we aimed at disclosing the pathways that are molecularly deregulated in NMZL and we compare the molecular profile of NMZL with that of SMZL. These analyses identified a distinctive pattern of nonsilent somatic lesions in NMZL. In 35 NMZL patients, 41 genes were found recurrently affected in ≥3 (9%) cases, including highly prevalent molecular lesions of MLL2 (also known as KMT2D; 34%), PTPRD (20%), NOTCH2 (20%), and KLF2 (17%). Mutations of PTPRD, a receptor-type protein tyrosine phosphatase regulating cell growth, were enriched in NMZL across mature B-cell tumors, functionally caused the loss of the phosphatase activity of PTPRD, and were associated with cell-cycle transcriptional program deregulation and increased proliferation index in NMZL. Although NMZL shared with SMZL a common mutation profile, NMZL harbored PTPRD lesions that were otherwise absent in SMZL. Collectively, these findings provide new insights into the genetics of NMZL, identify PTPRD lesions as a novel marker for this lymphoma across mature B-cell tumors, and support the distinction of NMZL as an independent clinicopathologic entity within the current lymphoma classification. PMID:27335277

  14. The genetics of nodal marginal zone lymphoma.

    PubMed

    Spina, Valeria; Khiabanian, Hossein; Messina, Monica; Monti, Sara; Cascione, Luciano; Bruscaggin, Alessio; Spaccarotella, Elisa; Holmes, Antony B; Arcaini, Luca; Lucioni, Marco; Tabbò, Fabrizio; Zairis, Sakellarios; Diop, Fary; Cerri, Michaela; Chiaretti, Sabina; Marasca, Roberto; Ponzoni, Maurilio; Deaglio, Silvia; Ramponi, Antonio; Tiacci, Enrico; Pasqualucci, Laura; Paulli, Marco; Falini, Brunangelo; Inghirami, Giorgio; Bertoni, Francesco; Foà, Robin; Rabadan, Raul; Gaidano, Gianluca; Rossi, Davide

    2016-09-01

    Nodal marginal zone lymphoma (NMZL) is a rare, indolent B-cell tumor that is distinguished from splenic marginal zone lymphoma (SMZL) by the different pattern of dissemination. NMZL still lacks distinct markers and remains orphan of specific cancer gene lesions. By combining whole-exome sequencing, targeted sequencing of tumor-related genes, whole-transcriptome sequencing, and high-resolution single nucleotide polymorphism array analysis, we aimed at disclosing the pathways that are molecularly deregulated in NMZL and we compare the molecular profile of NMZL with that of SMZL. These analyses identified a distinctive pattern of nonsilent somatic lesions in NMZL. In 35 NMZL patients, 41 genes were found recurrently affected in ≥3 (9%) cases, including highly prevalent molecular lesions of MLL2 (also known as KMT2D; 34%), PTPRD (20%), NOTCH2 (20%), and KLF2 (17%). Mutations of PTPRD, a receptor-type protein tyrosine phosphatase regulating cell growth, were enriched in NMZL across mature B-cell tumors, functionally caused the loss of the phosphatase activity of PTPRD, and were associated with cell-cycle transcriptional program deregulation and increased proliferation index in NMZL. Although NMZL shared with SMZL a common mutation profile, NMZL harbored PTPRD lesions that were otherwise absent in SMZL. Collectively, these findings provide new insights into the genetics of NMZL, identify PTPRD lesions as a novel marker for this lymphoma across mature B-cell tumors, and support the distinction of NMZL as an independent clinicopathologic entity within the current lymphoma classification. PMID:27335277

  15. Beyond the classic thermoneutral zone

    PubMed Central

    Kingma, Boris RM; Frijns, Arjan JH; Schellen, Lisje; van Marken Lichtenbelt, Wouter D

    2014-01-01

    The thermoneutral zone is defined as the range of ambient temperatures where the body can maintain its core temperature solely through regulating dry heat loss, i.e., skin blood flow. A living body can only maintain its core temperature when heat production and heat loss are balanced. That means that heat transport from body core to skin must equal heat transport from skin to the environment. This study focuses on what combinations of core and skin temperature satisfy the biophysical requirements of being in the thermoneutral zone for humans. Moreover, consequences are considered of changes in insulation and adding restrictions such as thermal comfort (i.e. driver for thermal behavior). A biophysical model was developed that calculates heat transport within a body, taking into account metabolic heat production, tissue insulation, and heat distribution by blood flow and equates that to heat loss to the environment, considering skin temperature, ambient temperature and other physical parameters. The biophysical analysis shows that the steady-state ambient temperature range associated with the thermoneutral zone does not guarantee that the body is in thermal balance at basal metabolic rate per se. Instead, depending on the combination of core temperature, mean skin temperature and ambient temperature, the body may require significant increases in heat production or heat loss to maintain stable core temperature. Therefore, the definition of the thermoneutral zone might need to be reformulated. Furthermore, after adding restrictions on skin temperature for thermal comfort, the ambient temperature range associated with thermal comfort is smaller than the thermoneutral zone. This, assuming animals seek thermal comfort, suggests that thermal behavior may be initiated already before the boundaries of the thermoneutral zone are reached. PMID:27583296

  16. Beyond the classic thermoneutral zone

    PubMed Central

    Kingma, Boris RM; Frijns, Arjan JH; Schellen, Lisje; van Marken Lichtenbelt, Wouter D

    2014-01-01

    The thermoneutral zone is defined as the range of ambient temperatures where the body can maintain its core temperature solely through regulating dry heat loss, i.e., skin blood flow. A living body can only maintain its core temperature when heat production and heat loss are balanced. That means that heat transport from body core to skin must equal heat transport from skin to the environment. This study focuses on what combinations of core and skin temperature satisfy the biophysical requirements of being in the thermoneutral zone for humans. Moreover, consequences are considered of changes in insulation and adding restrictions such as thermal comfort (i.e. driver for thermal behavior). A biophysical model was developed that calculates heat transport within a body, taking into account metabolic heat production, tissue insulation, and heat distribution by blood flow and equates that to heat loss to the environment, considering skin temperature, ambient temperature and other physical parameters. The biophysical analysis shows that the steady-state ambient temperature range associated with the thermoneutral zone does not guarantee that the body is in thermal balance at basal metabolic rate per se. Instead, depending on the combination of core temperature, mean skin temperature and ambient temperature, the body may require significant increases in heat production or heat loss to maintain stable core temperature. Therefore, the definition of the thermoneutral zone might need to be reformulated. Furthermore, after adding restrictions on skin temperature for thermal comfort, the ambient temperature range associated with thermal comfort is smaller than the thermoneutral zone. This, assuming animals seek thermal comfort, suggests that thermal behavior may be initiated already before the boundaries of the thermoneutral zone are reached.

  17. Metagenome of a versatile chemolithoautotroph from expanding oceanic dead zones.

    PubMed

    Walsh, David A; Zaikova, Elena; Howes, Charles G; Song, Young C; Wright, Jody J; Tringe, Susannah G; Tortell, Philippe D; Hallam, Steven J

    2009-10-23

    Oxygen minimum zones, also known as oceanic "dead zones," are widespread oceanographic features currently expanding because of global warming. Although inhospitable to metazoan life, they support a cryptic microbiota whose metabolic activities affect nutrient and trace gas cycling within the global ocean. Here, we report metagenomic analyses of a ubiquitous and abundant but uncultivated oxygen minimum zone microbe (SUP05) related to chemoautotrophic gill symbionts of deep-sea clams and mussels. The SUP05 metagenome harbors a versatile repertoire of genes mediating autotrophic carbon assimilation, sulfur oxidation, and nitrate respiration responsive to a wide range of water-column redox states. Our analysis provides a genomic foundation for understanding the ecological and biogeochemical role of pelagic SUP05 in oxygen-deficient oceanic waters and its potential sensitivity to environmental changes.

  18. Metagenome of a versatile chemolithoautotroph from expanding oceanic dead zones.

    PubMed

    Walsh, David A; Zaikova, Elena; Howes, Charles G; Song, Young C; Wright, Jody J; Tringe, Susannah G; Tortell, Philippe D; Hallam, Steven J

    2009-10-23

    Oxygen minimum zones, also known as oceanic "dead zones," are widespread oceanographic features currently expanding because of global warming. Although inhospitable to metazoan life, they support a cryptic microbiota whose metabolic activities affect nutrient and trace gas cycling within the global ocean. Here, we report metagenomic analyses of a ubiquitous and abundant but uncultivated oxygen minimum zone microbe (SUP05) related to chemoautotrophic gill symbionts of deep-sea clams and mussels. The SUP05 metagenome harbors a versatile repertoire of genes mediating autotrophic carbon assimilation, sulfur oxidation, and nitrate respiration responsive to a wide range of water-column redox states. Our analysis provides a genomic foundation for understanding the ecological and biogeochemical role of pelagic SUP05 in oxygen-deficient oceanic waters and its potential sensitivity to environmental changes. PMID:19900896

  19. Spin transition zone in Earth's lower mantle

    SciTech Connect

    Lin, J.-F.; Vanko, G.; Jacobsen, S.D.; Iota, V.; Struzhkin, V.V.; Prakapenka, V.B.; Kuznetsov, A.; Yoo, C.-S.

    2008-06-16

    Mineral properties in Earth's lower mantle are affected by iron electronic states, but representative pressures and temperatures have not yet been probed. Spin states of iron in lower-mantle ferropericlase have been measured up to 95 gigapascals and 2000 kelvin with x-ray emission in a laser-heated diamond cell. A gradual spin transition of iron occurs over a pressure-temperature range extending from about 1000 kilometers in depth and 1900 kelvin to 2200 kilometers and 2300 kelvin in the lower mantle. Because low-spin ferropericlase exhibits higher density and faster sound velocities relative to the high-spin ferropericlase, the observed increase in low-spin (Mg,Fe)O at mid-lower mantle conditions would manifest seismically as a lower-mantle spin transition zone characterized by a steeper-than-normal density gradient.

  20. Analytical model for radionuclide transport in the buffer zone of the deep geological disposal

    NASA Astrophysics Data System (ADS)

    Tsao, L. D.; Chen, J. S.; Li, M. H.

    2015-12-01

    Radioactive nuclear waste poses long-term threat to human beings and the environment because that remains radioactive after millions of years. Therefore, radioactive wastes must be isolated from the living environment for millennia. A deep geological disposal entails a combination of four parts: vitrified waste form, imaginary zone, buffer zone and excavation-affected zone. The buffer zone constituted by bentonite clay provides a high level of containment of the radioactivity in the wastes over a very long time period. Analytical solution is an efficient tool for the performance evaluation of the buffer zone. This study develops a new analytical model to diffusion equation in cylindrical coordinate for describing radionuclide transport in the buffer zone. The derived solution is compared against the previous solution to illustrate the validity of previous solution which was derived using a diffusion equation in Cartesian coordinates.

  1. A method for generating volumetric fault zone grids for pillar gridded reservoir models

    NASA Astrophysics Data System (ADS)

    Qu, Dongfang; Røe, Per; Tveranger, Jan

    2015-08-01

    The internal structure and petrophysical property distribution of fault zones are commonly exceedingly complex compared to the surrounding host rock from which they are derived. This in turn produces highly complex fluid flow patterns which affect petroleum migration and trapping as well as reservoir behavior during production and injection. Detailed rendering and forecasting of fluid flow inside fault zones require high-resolution, explicit models of fault zone structure and properties. A fundamental requirement for achieving this is the ability to create volumetric grids in which modeling of fault zone structures and properties can be performed. Answering this need, a method for generating volumetric fault zone grids which can be seamlessly integrated into existing standard reservoir modeling tools is presented. The algorithm has been tested on a wide range of fault configurations of varying complexity, providing flexible modeling grids which in turn can be populated with fault zone structures and properties.

  2. 76 FR 44803 - Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-27

    ...-2010-0079 Port Arthur, TX Safety Zone (Part 165)..... 2/2/2010 USCG-2010-0080 Sabine, TX Security Zone...-0107 Sabine, TX Security Zone (Part 165)... 2/11/2010 USCG-2010-0108 Charleston, WV Safety Zone (Part...). USCG-2010-0218 Sabine, TX Security Zone (Part 165)... 4/1/2010 USCG-2010-0219 Waterway, TX...

  3. Evaluation of flow properties in the weldments of vanadium alloys using a novel indentation technique

    SciTech Connect

    Gubbi, A.N.; Rowcliffe, A.F.; Lee, E.H.; King, J.F.; Goodwin, G.M.

    1996-10-01

    Automated Ball Indentation (ABI) testing, was successfully employed to determine the flow properties of the fusion zone, heat affected zone (HAZ), and base metal of the gas tungsten arc (GTA) and electron beam (EB) welds of the V-4Cr-4Ti (large heat no. 832665) and the V-5Cr-5Ti (heat 832394) alloys. ABI test results showed a clear distinction among the properties of the fusion zone, HAZ, and base metal in both GTA and EB welds of the two alloys. GTA and EB welds of both V-4Cr-4Ti and V-5Cr-5Ti alloys show strengthening of both the fusion zone and the HAZ (compared to base metal) with the fusion zone having higher strength than the HAZ. These data correlate well with the Brinell hardness. On the other hand, GTA welds of both alloys, after a post-weld heat treatment of 950{degrees}C for 2 h, show a recovery of the properties to base metal values with V-5Cr-5Ti showing a higher degree of recovery compared to V-4Cr-4Ti. These measurements correlate with the reported recovery of the Charpy impact properties.

  4. Tectonics and the photosynthetic habitable zone (Invited)

    NASA Astrophysics Data System (ADS)

    Sleep, N. H.

    2009-12-01

    The traditional habitable zone lies between an inner stellar radius where the surface of the planet becomes too hot for liquid water carbon-based life and on outer radius, where the surface freezes. It is effectively the zone where photosynthesis is feasible. The concept extends to putative life on objects with liquid methane at the surface, like Titan. As a practical matter, photosynthesis leaves detectable biosignatures in the geological record; black shale on the Earth indicates that sulfide and probably FeO based photosynthesis existed by 3.8 Ga. The hard crustal rocks and the mantle sequester numerous photosynthetic biosignatures. Photosynthesis can produce detectable free oxygen with ozone in the atmosphere of extrasolar planets. In contrast, there is no outer limit for subsurface life in large silicate objects. Pre-photosynthetic niches are dependable but meager and not very detectable at great antiquity or great distance, with global productivity less than 1e-3 of the photosynthetic ones. Photosynthetic organisms have bountiful energy that modifies their surface environment and even tectonics. For example, metamorphic rocks formed at the expense of thick black shale are highly radioactive and hence self-fluxing. Active tectonics with volcanism and metamorphism prevents volatiles from being sequestered in the subsurface as on Mars. A heat-pipe object, like a larger Io, differs from the Earth in that the volatiles return to the deep interior distributed within massive volcanic deposits rather than concentrated in the shallow oceanic crust. One the Earth, the return of water to the surface by arc volcanoes controls its mantle abundance at the transition between behaving as a trace element and behaving as a major element that affects melting. The ocean accumulates the water that the mantle and crust do not take. The Earth has the “right” amount of water that erosion/deposition and tectonics both tend to maintain near sea level surfaces. The mantle contains

  5. Effect of vadose zone on the steady-state leakage rates from landfill barrier systems

    SciTech Connect

    Celik, B. Rowe, R.K. Unlue, K.

    2009-01-15

    Leakage rates are evaluated for a landfill barrier system having a compacted clay liner (CCL) underlain by a vadose zone of variable thickness. A numerical unsaturated flow model SEEP/W is used to simulate the moisture flow regime and steady-state leakage rates for the cases of unsaturated zones with different soil types and thicknesses. The results of the simulations demonstrate that harmonic mean hydraulic conductivity of coarse textured vadose zones is 3-4 orders of magnitude less than saturated hydraulic conductivity; whereas, the difference is only one order of magnitude for fine textured vadose zones. For both coarse and fine textured vadose zones, the effective hydraulic conductivity of the barrier system and the leakage rate to an underlying aquifer increases with increasing thickness of the vadose zone and ultimately reaches an asymptotic value for a coarse textured vadose zone thickness of about 10 m and a fine textured vadose zone thickness of about 5 m. Therefore, the fine and coarse textured vadose zones thicker than about 5 m and 10 m, respectively, act as an effective part of the barrier systems examined. Although the thickness of vadose zone affects the effective hydraulic conductivity of the overall barrier system, the results demonstrated that the hydraulic conductivity of the CCL is the dominant factor controlling the steady-state leakage rates through barrier systems having single low permeability clay layers.

  6. Float zone experiments in space

    NASA Technical Reports Server (NTRS)

    Verhoeven, J. D.; Noack, M. A.; Gill, W. N.; Hau, C. C.

    1984-01-01

    The molten zone/freezing crystal interface system and all the mechanisms were examined. If Marangoni convection produces oscillatory flows in the float zone of semiconductor materials, such as silicon, then it is unlikely that superior quality crystals can be grown in space using this process. The major goals were: (1) to determine the conditions for the onset of Marangoni flows in molten tin, a model system for low Prandtl number molten semiconductor materials; (2) to determine whether the flows can be suppressed by a thin oxide layer; and (3) based on experimental and mathematical analysis, to predict whether oscillatory flows will occur in the float zone silicon geometry in space, and if so, could it be suppressed by thin oxide or nitride films. Techniques were developed to analyze molten tin surfaces in a UHV system in a disk float zone geometry to minimize buoyancy flows. The critical Marangoni number for onset of oscillatory flows was determined to be greater than 4300 on atomically clean molten tin surfaces.

  7. Building a Subduction Zone Observatory

    USGS Publications Warehouse

    Gomberg, Joan S.; Bodin, Paul; Bourgeois, Jody; Cashman, Susan; Cowan, Darrel; Creager, Kenneth C.; Crowell, Brendan; Duvall, Alison; Frankel, Arthur; Gonzalez, Frank; Houston, Heidi; Johnson, Paul; Kelsey, Harvey; Miller, Una; Roland, Emily C.; Schmidt, David; Staisch, Lydia; Vidale, John; Wilcock, William; Wirth, Erin

    2016-01-01

    Subduction zones contain many of Earth’s most remarkable geologic structures, from the deepest oceanic trenches to glacier-covered mountains and steaming volcanoes. These environments formed through spectacular events: Nature’s largest earthquakes, tsunamis, and volcanic eruptions are born here.

  8. Comfort Zone: Model or Metaphor

    ERIC Educational Resources Information Center

    Brown, Mike

    2008-01-01

    The comfort zone model is widespread within adventure education literature. It is based on the belief that when placed in a stressful situation people will respond by overcoming their fear and therefore grow as individuals. This model is often presented to participants prior to activities with a highly perceived sense of risk and challenge which…

  9. Issues in Coastal Zone Management.

    ERIC Educational Resources Information Center

    Davis, Derrin

    1992-01-01

    Addresses the following issues relevant to coastal zone management: overcrowding, resource exploitation, pollution, agriculture, fisheries, industrial, and other uses. Describes conflicts and trade-offs in management typified by fragmented agency decision making. Discusses implications of the greenhouse effect, sustainable development, and the…

  10. Zone refining of plutonium metal

    SciTech Connect

    1997-05-01

    The purpose of this study was to investigate zone refining techniques for the purification of plutonium metal. The redistribution of 10 impurity elements from zone melting was examined. Four tantalum boats were loaded with plutonium impurity alloy, placed in a vacuum furnace, heated to 700{degrees}C, and held at temperature for one hour. Ten passes were made with each boat. Metallographic and chemical analyses performed on the plutonium rods showed that, after 10 passes, moderate movement of certain elements were achieved. Molten zone speeds of 1 or 2 inches per hour had no effect on impurity element movement. Likewise, the application of constant or variable power had no effect on impurity movement. The study implies that development of a zone refining process to purify plutonium is feasible. Development of a process will be hampered by two factors: (1) the effect on impurity element redistribution of the oxide layer formed on the exposed surface of the material is not understood, and (2) the tantalum container material is not inert in the presence of plutonium. Cold boat studies are planned, with higher temperature and vacuum levels, to determine the effect on these factors. 5 refs., 1 tab., 5 figs.

  11. Comparable Habitable Zones of Stars

    NASA Video Gallery

    The habitable zone is the distance from a star where one can have liquid water on the surface of a planet. If a planet is too close to its parent star, it will be too hot and water would have evapo...

  12. Method and apparatus for welding precipitation hardenable materials

    DOEpatents

    Murray, Jr., Holt; Harris, Ian D.; Ratka, John O.; Spiegelberg, William D.

    1994-01-01

    A method for welding together members consisting of precipitation age hardened materials includes the steps of selecting a weld filler material that has substantially the same composition as the materials being joined, and an age hardening characteristic temperature age threshold below that of the aging kinetic temperature range of the materials being joined, whereby after welding the members together, the resulting weld and heat affected zone (HAZ) are heat treated at a temperature below that of the kinetic temperature range of the materials joined, for obtaining substantially the same mechanical characteristics for the weld and HAZ, as for the parent material of the members joined.

  13. Method and apparatus for welding precipitation hardenable materials

    DOEpatents

    Murray, H. Jr.; Harris, I.D.; Ratka, J.O.; Spiegelberg, W.D.

    1994-06-28

    A method for welding together members consisting of precipitation age hardened materials includes the steps of selecting a weld filler material that has substantially the same composition as the materials being joined, and an age hardening characteristic temperature age threshold below that of the aging kinetic temperature range of the materials being joined, whereby after welding the members together, the resulting weld and heat affected zone (HAZ) are heat treated at a temperature below that of the kinetic temperature range of the materials joined, for obtaining substantially the same mechanical characteristics for the weld and HAZ, as for the parent material of the members joined. 5 figures.

  14. Analysis of the Influence of Laser Welding on Fatigue Crack Growth Behavior in a Newly Developed Nickel-Base Superalloy

    NASA Astrophysics Data System (ADS)

    Buckson, R. A.; Ojo, O. A.

    2015-01-01

    The influence of laser welding on fatigue crack growth (FCG) behavior of a newly developed nickel-base superalloy, Haynes 282 was studied. Laser welding resulted in cracking in the heat affected zone (HAZ) of the alloy during welding and FCG test results show that this produces deleterious effect on the fatigue crack growth behavior of Haynes 282. However, two post weld heat treatments, including a new thermal treatment schedule developed in this work, are used to significantly improve the resistance of the Haynes 282 fatigue crack growth after laser welding. The effects of laser welding and thermal treatments are discussed in terms of HAZ cracking and heterogeneity of slip, respectively.

  15. Review on symmetric structures in ductile shear zones

    NASA Astrophysics Data System (ADS)

    Mukherjee, Soumyajit

    2016-07-01

    Symmetric structures in ductile shear zones range widely in shapes and geneses. Matrix rheology, its flow pattern, its competency contrast with the clast, degree of slip of the clast, shear intensity and its variation across shear zone and deformation temperature, and degree of confinement of clast in shear zones affects (independently) the degree of symmetry of objects. Kinematic vorticity number is one of the parameters that govern tail geometry across clasts. For example, symmetric and nearly straight tails develop if the clast-matrix system underwent dominantly a pure shear/compression. Prolonged deformation and concomitant recrystallization can significantly change the degree of symmetry of clasts. Angular relation between two shear zones or between a shear zone and anisotropy determines fundamentally the degree of symmetry of lozenges. Symmetry of boudinaged clasts too depends on competency contrast between the matrix and clast in some cases, and on the degrees of slip of inter-boudin surfaces and pure shear. Parasitic folds and post-tectonic veins are usually symmetric.

  16. 'One physical system': Tansley's ecosystem as Earth's critical zone.

    PubMed

    Richter, Daniel deB; Billings, Sharon A

    2015-05-01

    Integrative concepts of the biosphere, ecosystem, biogeocenosis and, recently, Earth's critical zone embrace scientific disciplines that link matter, energy and organisms in a systems-level understanding of our remarkable planet. Here, we assert the congruence of Tansley's (1935) venerable ecosystem concept of 'one physical system' with Earth science's critical zone. Ecosystems and critical zones are congruent across spatial-temporal scales from vegetation-clad weathering profiles and hillslopes, small catchments, landscapes, river basins, continents, to Earth's whole terrestrial surface. What may be less obvious is congruence in the vertical dimension. We use ecosystem metabolism to argue that full accounting of photosynthetically fixed carbon includes respiratory CO₂ and carbonic acid that propagate to the base of the critical zone itself. Although a small fraction of respiration, the downward diffusion of CO₂ helps determine rates of soil formation and, ultimately, ecosystem evolution and resilience. Because life in the upper portions of terrestrial ecosystems significantly affects biogeochemistry throughout weathering profiles, the lower boundaries of most terrestrial ecosystems have been demarcated at depths too shallow to permit a complete understanding of ecosystem structure and function. Opportunities abound to explore connections between upper and lower components of critical-zone ecosystems, between soils and streams in watersheds, and between plant-derived CO₂ and deep microbial communities and mineral weathering.

  17. 'One physical system': Tansley's ecosystem as Earth's critical zone.

    PubMed

    Richter, Daniel deB; Billings, Sharon A

    2015-05-01

    Integrative concepts of the biosphere, ecosystem, biogeocenosis and, recently, Earth's critical zone embrace scientific disciplines that link matter, energy and organisms in a systems-level understanding of our remarkable planet. Here, we assert the congruence of Tansley's (1935) venerable ecosystem concept of 'one physical system' with Earth science's critical zone. Ecosystems and critical zones are congruent across spatial-temporal scales from vegetation-clad weathering profiles and hillslopes, small catchments, landscapes, river basins, continents, to Earth's whole terrestrial surface. What may be less obvious is congruence in the vertical dimension. We use ecosystem metabolism to argue that full accounting of photosynthetically fixed carbon includes respiratory CO₂ and carbonic acid that propagate to the base of the critical zone itself. Although a small fraction of respiration, the downward diffusion of CO₂ helps determine rates of soil formation and, ultimately, ecosystem evolution and resilience. Because life in the upper portions of terrestrial ecosystems significantly affects biogeochemistry throughout weathering profiles, the lower boundaries of most terrestrial ecosystems have been demarcated at depths too shallow to permit a complete understanding of ecosystem structure and function. Opportunities abound to explore connections between upper and lower components of critical-zone ecosystems, between soils and streams in watersheds, and between plant-derived CO₂ and deep microbial communities and mineral weathering. PMID:25731586

  18. Pollution of water resources due to industrialization in arid zone of Rajasthan, India.

    PubMed

    Khan, M A

    2001-04-01

    In arid zone of Rajasthan, India, nearly 21,900 hm2 area along Bandi River has been affected by industrial effluent discharge into the river bed. Analysis of groundwater samples collected from these sites revealed that area at the vicinity of the river is most affected. The effluent water in the river is the main source of contamination of ground water. Concentration of sodium and chloride has been higher with proportional increase in TDS and EC value in the area within zone A (river water), zone B (0-100 m), zone C (101-250 m), zone D (251-500 m) and zone E (501-1000 m). There is decreasing trend in ion concentration from zone A to zone E and F, reflecting reduced effect of effluents. The pollution of water resources has resulted in the degradation of other natural resources such as land, soil and vegetation. Nearly 4463 hm2 (20.38%) area has been very severely affected. EC value at places exceeds 20 dS/m. Soil and land have become hard, compact and saline. Cropping intensity has declined. In the area (3633 hm2) affected severely, the EC value of water varies from 10-20 dS/m. Irrigation with such water has created problem of salinity, sodicity in soils. Herbal biomass declined considerably. Double cropping has almost stopped. Almost 8494 hm2 area is affected moderately. EC of ground water varies from 5 to 10 dS/m. Fragile surface crust, declining trend of phosphorous and potassium in the soil, poor density of natural vegetation are significant manifestations. Apart from this, 5305 hm2 area is slightly affected.

  19. Floating zone melting of cadmium telluride

    NASA Technical Reports Server (NTRS)

    Chang, Wen-Ming; Regel, L. L.; Wilcox, W. R.

    1992-01-01

    To produce superior crystals of cadmium telluride, floating zone melting in space has been proposed. Techniques required for floating zone melting of cadmium telluride are being developed. We have successfully float-zoned cadmium telluride on earth using square rods. A resistance heater was constructed for forming the molten zone. Evaporation of the molten zone was controlled by adding excess cadmium to the growth ampoule combined with heating of the entire ampoule. An effective method to hold the feed rod was developed. Slow rotation of the growth ampoule was proven experimentally to be necessary to achieve a complete symmetric molten zone. Most of the resultant cylindrical rods were single crystals with twins. Still needed is a suitable automatic method to control the zone length. We tried a fiber optical technique to control the zone length, but experiments showed that application of this technique to automate zone length control is unlikely to be successful.

  20. Overlap zoned electrically heated particulate filter

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Chapman, Mark R [Brighton, MI

    2011-07-19

    A system includes a particulate matter (PM) filter that includes an upstream end for receiving exhaust gas and a downstream end. A zoned heater is arranged spaced from the upstream end and comprises N zones, where N is an integer greater than one, wherein each of the N zones comprises M sub-zones, where M is an integer greater than or equal to one, and wherein the N zones and the M sub-zones are arranged in P layers, where P is an integer greater than one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones and deactivates non-selected ones of the N zones.

  1. Affective Dynamics in Psychopathology

    PubMed Central

    Trull, Timothy J.; Lane, Sean P.; Koval, Peter; Ebner-Priemer, Ulrich W.

    2016-01-01

    We discuss three varieties of affective dynamics (affective instability, emotional inertia, and emotional differentiation). In each case, we suggest how these affective dynamics should be operationalized and measured in daily life using time-intensive methods, like ecological momentary assessment or ambulatory assessment, and recommend time-sensitive analyses that take into account not only the variability but also the temporal dependency of reports. Studies that explore how these affective dynamics are associated with psychological disorders and symptoms are reviewed, and we emphasize that these affective processes are within a nexus of other components of emotion regulation.

  2. The Galicia-Ossa-Morena Zone: Proposal for a new zone of the Iberian Massif. Variscan implications

    NASA Astrophysics Data System (ADS)

    Arenas, Ricardo; Díez Fernández, Rubén; Rubio Pascual, Francisco J.; Sánchez Martínez, Sonia; Martín Parra, Luis Miguel; Matas, Jerónimo; González del Tánago, José; Jiménez-Díaz, Alberto; Fuenlabrada, Jose M.; Andonaegui, Pilar; Garcia-Casco, Antonio

    2016-06-01

    Correlation of a group of allochthonous terranes (referred to as basal, ophiolitic and upper units) exposed in the NW and SW of the Iberian Massif, is used to propose a new geotectonic zone in the southern branch of the Variscan Orogen: the Galicia-Ossa-Morena Zone. Recent advances in SW Iberia identify most of the former Ossa-Morena Zone as another allochthonous complex of the Iberian Massif, the Ossa-Morena Complex, equivalent to the Cabo Ortegal, Órdenes, Malpica-Tui, Bragança and Morais complexes described in NW Iberia. The new geotectonic zone and its counterparts along the rest of the Variscan Orogen constitute an Internal Variscan Zone with ophiolites and units affected by high-P metamorphism. The Galicia-Ossa-Morena Zone includes a Variscan suture and pieces of continental crust bearing the imprint of Ediacaran-Cambrian events related to the activity of peri-Gondwanan magmatic arcs (Cadomian orogenesis). In the Iberian Massif, the general structure of this geotectonic zone represents a duplication of the Gondwanan platform, the outboard sections being juxtaposed on top of domains located closer to the mainland before amalgamation. This interpretation offers an explanation that overcomes some issues regarding the differences between the stratigraphic and paleontological record of the central and southern sections of the Iberian Massif. Also, equivalent structural relationships between other major geotectonic domains of the rest of the Variscan Orogen are consistent with our interpretation and allow suspecting similar configurations along strike of the orogen. A number of issues may be put forward in this respect that potentially open new lines of thinking about the architecture of the Variscan Orogen.

  3. Unsaturated Zone and Saturated Zone Transport Properties (U0100)

    SciTech Connect

    J. Conca

    2000-12-20

    This Analysis/Model Report (AMR) summarizes transport properties for the lower unsaturated zone hydrogeologic units and the saturated zone at Yucca Mountain and provides a summary of data from the Busted Butte Unsaturated Zone Transport Test (UZTT). The purpose of this report is to summarize the sorption and transport knowledge relevant to flow and transport in the units below Yucca Mountain and to provide backup documentation for the sorption parameters decided upon for each rock type. Because of the complexity of processes such as sorption, and because of the lack of direct data for many conditions that may be relevant for Yucca Mountain, data from systems outside of Yucca Mountain are also included. The data reported in this AMR will be used in Total System Performance Assessment (TSPA) calculations and as general scientific support for various Process Model Reports (PMRs) requiring knowledge of the transport properties of different materials. This report provides, but is not limited to, sorption coefficients and other relevant thermodynamic and transport properties for the radioisotopes of concern, especially neptunium (Np), plutonium (Pu), Uranium (U), technetium (Tc), iodine (I), and selenium (Se). The unsaturated-zone (UZ) transport properties in the vitric Calico Hills (CHv) are discussed, as are colloidal transport data based on the Busted Butte UZTT, the saturated tuff, and alluvium. These values were determined through expert elicitation, direct measurements, and data analysis. The transport parameters include information on interactions of the fractures and matrix. In addition, core matrix permeability data from the Busted Butte UZTT are summarized by both percent alteration and dispersion.

  4. Tensile properties of vanadium-base alloys with a tungsten/inert-gas weld zone

    SciTech Connect

    Loomis, B.A.; Konicek, C.F.; Nowicki, L.J.; Smith, D.L.

    1992-12-31

    The tensile properties of V-(0-20)Ti and V-(O-15)Cr-5Ti alloys after butt-joining by tungsten/inert-gas (TIG) welding were determined from tests at 25{degrees}C. Tensile tests were conducted on both annealed and cold-worked materials with a TIG weld zone. The tensile properties of these materials were strongly influenced by the microstructure in the heat-affected zone adjacent to the weld zone and by the intrinsic fracture toughness of the alloys. TIG weld zones in these vanadium-base alloys had tensile properties comparable to those of recrystallized alloys without a weld zone. Least affected by the TIG welding were tensile properties of the V-5Ti and V-5Cr-5Ti alloys. Although the tensile properties of the V-5Ti and V- 5Cr-5Ti alloys with a TIG weld zone were acceptable for structural material, these properties would be improved by optimization of the welding parameters for minimum grain size in the heat-affected zone.

  5. 9 CFR 77.9 - Modified accredited advanced States or zones.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Register citations affecting § 77.9, see the List of CFR Sections Affected, which appears in the Finding... TUBERCULOSIS Cattle and Bison § 77.9 Modified accredited advanced States or zones. (a) The following are... “Uniform Methods and Rules—Bovine Tuberculosis Eradication” (January 22, 1999), which is incorporated...

  6. Concepts of the Habitable Zone

    NASA Astrophysics Data System (ADS)

    Kaltenegger, L.

    2012-04-01

    The HZ around a single star has been calculated by several authors. Two concepts are commonly used throughout the literature for cloud free (see Kasting et al.1993, Underwood et al.2003) and cloudy atmospheres (Selsis et al.2007) which have been derived from the same model originally proposed by Kasting et al.(1993). The main differences among studies of the HZ are the imposed climatic constraints such as a CO2/H2O/N2 atmosphere with varying CO2/H2O/N2 concentrations (e.g., Earth's), or model atmospheres with high H2 concentrations (Gaidos&Pierrehumbert 2010) or limited water supply (Abe et al.2011). We discuss the implication of these constraints on the Habitable Zone and its resulting limits as well as detectable spectral features in a planet's rocky atmosphere that could be used to test our concept of the Habitable Zone.

  7. Satellite-Derived Management Zones

    NASA Technical Reports Server (NTRS)

    Lepoutre, Damien; Layrol, Laurent

    2005-01-01

    The term "satellite-derived management zones" (SAMZ) denotes agricultural management zones that are subdivisions of large fields and that are derived from images of the fields acquired by instruments aboard Earth-orbiting satellites during approximately the past 15 years. "SAMZ" also denotes the methodology and the software that implements the methodology for creating such zones. The SAMZ approach is one of several products of continuing efforts to realize a concept of precision agriculture, which involves optimal variations in seeding, in application of chemicals, and in irrigation, plus decisions to farm or not to farm certain portions of fields, all in an effort to maximize profitability in view of spatial and temporal variations in the growth and health of crops, and in the chemical and physical conditions of soils. As used here, "management zone" signifies, more precisely, a subdivision of a field within which the crop-production behavior is regarded as homogeneous. From the perspective of precision agriculture, management zones are the smallest subdivisions between which the seeding, application of chemicals, and other management parameters are to be varied. In the SAMZ approach, the main sources of data are the archives of satellite imagery that have been collected over the years for diverse purposes. One of the main advantages afforded by the SAMZ approach is that the data in these archives can be reused for purposes of precision agriculture at low cost. De facto, these archives contain information on all sources of variability within a field, including weather, crop types, crop management, soil types, and water drainage patterns. The SAMZ methodology involves the establishment of a Web-based interface based on an algorithm that generates management zones automatically and quickly from archival satellite image data in response to requests from farmers. A farmer can make a request by either uploading data describing a field boundary to the Web site or else

  8. Topography of Human Erogenous Zones.

    PubMed

    Nummenmaa, Lauri; Suvilehto, Juulia T; Glerean, Enrico; Santtila, Pekka; Hietanen, Jari K

    2016-07-01

    Touching is a powerful means for eliciting sexual arousal. Here, we establish the topographical organization of bodily regions triggering sexual arousal in humans. A total of 704 participants were shown images of same and opposite sex bodies and asked to color the bodily regions whose touching they or members of the opposite sex would experience as sexually arousing while masturbating or having sex with a partner. Resulting erogenous zone maps (EZMs) revealed that the whole body was sensitive to sexual touching, with erogenous hotspots consisting of genitals, breasts, and anus. The EZM area was larger while having sex with a partner versus while masturbating, and was also dependent on sexual desire and heterosexual and homosexual interest levels. We conclude that tactile stimulation of practically all bodily regions may trigger sexual arousal. Extension of the erogenous zones while having sex with a partner may reflect the role of touching in maintenance of reproductive pair bonds.

  9. Definition of Management Zones for Enhancing Cultivated Land Conservation Using Combined Spatial Data

    NASA Astrophysics Data System (ADS)

    Li, Yan; Shi, Zhou; Wu, Hao-Xiang; Li, Feng; Li, Hong-Yi

    2013-10-01

    The loss of cultivated land has increasingly become an issue of regional and national concern in China. Definition of management zones is an important measure to protect limited cultivated land resource. In this study, combined spatial data were applied to define management zones in Fuyang city, China. The yield of cultivated land was first calculated and evaluated and the spatial distribution pattern mapped; the limiting factors affecting the yield were then explored; and their maps of the spatial variability were presented using geostatistics analysis. Data were jointly analyzed for management zone definition using a combination of principal component analysis with a fuzzy clustering method, two cluster validity functions were used to determine the optimal number of cluster. Finally one-way variance analysis was performed on 3,620 soil sampling points to assess how well the defined management zones reflected the soil properties and productivity level. It was shown that there existed great potential for increasing grain production, and the amount of cultivated land played a key role in maintaining security in grain production. Organic matter, total nitrogen, available phosphorus, elevation, thickness of the plow layer, and probability of irrigation guarantee were the main limiting factors affecting the yield. The optimal number of management zones was three, and there existed significantly statistical differences between the crop yield and field parameters in each defined management zone. Management zone I presented the highest potential crop yield, fertility level, and best agricultural production condition, whereas management zone III lowest. The study showed that the procedures used may be effective in automatically defining management zones; by the development of different management zones, different strategies of cultivated land management and practice in each zone could be determined, which is of great importance to enhance cultivated land conservation

  10. Definition of management zones for enhancing cultivated land conservation using combined spatial data.

    PubMed

    Li, Yan; Shi, Zhou; Wu, Hao-Xiang; Li, Feng; Li, Hong-Yi

    2013-10-01

    The loss of cultivated land has increasingly become an issue of regional and national concern in China. Definition of management zones is an important measure to protect limited cultivated land resource. In this study, combined spatial data were applied to define management zones in Fuyang city, China. The yield of cultivated land was first calculated and evaluated and the spatial distribution pattern mapped; the limiting factors affecting the yield were then explored; and their maps of the spatial variability were presented using geostatistics analysis. Data were jointly analyzed for management zone definition using a combination of principal component analysis with a fuzzy clustering method, two cluster validity functions were used to determine the optimal number of cluster. Finally one-way variance analysis was performed on 3,620 soil sampling points to assess how well the defined management zones reflected the soil properties and productivity level. It was shown that there existed great potential for increasing grain production, and the amount of cultivated land played a key role in maintaining security in grain production. Organic matter, total nitrogen, available phosphorus, elevation, thickness of the plow layer, and probability of irrigation guarantee were the main limiting factors affecting the yield. The optimal number of management zones was three, and there existed significantly statistical differences between the crop yield and field parameters in each defined management zone. Management zone I presented the highest potential crop yield, fertility level, and best agricultural production condition, whereas management zone III lowest. The study showed that the procedures used may be effective in automatically defining management zones; by the development of different management zones, different strategies of cultivated land management and practice in each zone could be determined, which is of great importance to enhance cultivated land conservation

  11. TASK 2: QUENCH ZONE SIMULATION

    SciTech Connect

    Fusselman, Steve

    2015-09-30

    Aerojet Rocketdyne (AR) has developed an innovative gasifier concept incorporating advanced technologies in ultra-dense phase dry feed system, rapid mix injector, and advanced component cooling to significantly improve gasifier performance, life, and cost compared to commercially available state-of-the-art systems. A key feature of the AR gasifier design is the transition from the gasifier outlet into the quench zone, where the raw syngas is cooled to ~ 400°C by injection and vaporization of atomized water. Earlier pilot plant testing revealed a propensity for the original gasifier outlet design to accumulate slag in the outlet, leading to erratic syngas flow from the outlet. Subsequent design modifications successfully resolved this issue in the pilot plant gasifier. In order to gain greater insight into the physical phenomena occurring within this zone, AR developed a cold flow simulation apparatus with Coanda Research & Development with a high degree of similitude to hot fire conditions with the pilot scale gasifier design, and capable of accommodating a scaled-down quench zone for a demonstration-scale gasifier. The objective of this task was to validate similitude of the cold flow simulation model by comparison of pilot-scale outlet design performance, and to assess demonstration scale gasifier design feasibility from testing of a scaled-down outlet design. Test results did exhibit a strong correspondence with the two pilot scale outlet designs, indicating credible similitude for the cold flow simulation device. Testing of the scaled-down outlet revealed important considerations in the design and operation of the demonstration scale gasifier, in particular pertaining to the relative momentum between the downcoming raw syngas and the sprayed quench water and associated impacts on flow patterns within the quench zone. This report describes key findings from the test program, including assessment of pilot plant configuration simulations relative to actual

  12. Geological factors affecting CO2 plume distribution

    USGS Publications Warehouse

    Frailey, S.M.; Leetaru, H.

    2009-01-01

    Understanding the lateral extent of a CO2 plume has important implications with regards to buying/leasing pore volume rights, defining the area of review for an injection permit, determining the extent of an MMV plan, and managing basin-scale sequestration from multiple injection sites. The vertical and lateral distribution of CO2 has implications with regards to estimating CO2 storage volume at a specific site and the pore pressure below the caprock. Geologic and flow characteristics such as effective permeability and porosity, capillary pressure, lateral and vertical permeability anisotropy, geologic structure, and thickness all influence and affect the plume distribution to varying degrees. Depending on the variations in these parameters one may dominate the shape and size of the plume. Additionally, these parameters do not necessarily act independently. A comparison of viscous and gravity forces will determine the degree of vertical and lateral flow. However, this is dependent on formation thickness. For example in a thick zone with injection near the base, the CO2 moves radially from the well but will slow at greater radii and vertical movement will dominate. Generally the CO2 plume will not appreciably move laterally until the caprock or a relatively low permeability interval is contacted by the CO2. Conversely, in a relatively thin zone with the injection interval over nearly the entire zone, near the wellbore the CO2 will be distributed over the entire vertical component and will move laterally much further with minimal vertical movement. Assuming no geologic structure, injecting into a thin zone or into a thick zone immediately under a caprock will result in a larger plume size. With a geologic structure such as an anticline, CO2 plume size may be restricted and injection immediately below the caprock may have less lateral plume growth because the structure will induce downward vertical movement of the CO2 until the outer edge of the plume reaches a spill

  13. Is there an Unhabitable Zone?

    NASA Astrophysics Data System (ADS)

    Leconte, Jeremy

    2015-07-01

    The universe is a vast place, and a blind search for life out there is short of impossible. Therefore, it is only natural to try and reduce the area to explore by putting in some additional assumptions based on a few educated guesses and a lot of "a priori" experience from what is life here on Earth. On our way along this appealing path, we have come up with a working definition of where life should be looked for: the so-called Traditional Habitable Zone (THZ). But as this concept has taken what seems to be an ever increasing significance in mission design and selection, it is important to understand the limitations to its definition and usefulness. To do so, I will thus try to address the following questions: Is a planet inside the THZ habitable? Is a planet outside this zone necessarily unhabitable? In fact, is there anything like an Unhabitable Zone, and don't we risk to miss the unexpected if we try too hard to find another version of ourselves among the stars?

  14. PLANT INVASIONS IN RHODE ISLAND RIPARIAN ZONES

    EPA Science Inventory

    The vegetation in riparian zones provides valuable wildlife habitat while enhancing instream habitat and water quality. Forest fragmentation, sunlit edges, and nutrient additions from adjacent development may be sources of stress on riparian zones. Landscape plants may include no...

  15. Oblique sinistral transpression in the Arabian shield: The timing and kinematics of a Neoproterozoic suture zone

    USGS Publications Warehouse

    Johnson, P.R.; Kattan, F.

    2001-01-01

    The Hulayfah-Ad Dafinah-Ruwah fault zone is a belt of highly strained rocks that extends in a broad curve across the northeastern Arabian shield. It is a subvertical shear zone, 5-30 km wide and over 600 km long, and is interpreted as a zone of oblique sinistral transpression that forms the suture between the Afif terrane and the Asir-Jiddah-Hijaz-Hulayfah superterrane. Available data suggest that the terranes began to converge sometime after 720 Ma, were in active contact at about 680 Ma, and were in place, with suturing complete, by 630 Ma, The fault zone was affected by sinistral horizontal and local vertical shear, and simultaneous flattening and fault-zone-parallel extension. Structures include sinistral sense-of-shear indicators, L-S tectonite, and coaxial stretching lineations and fold axes. The stretching lineations switch from subhorizontal to subvertical along the fault zone indicating significant variation in finite strain consistent with an origin by oblique transpression. The sense of shear on the fault zone suggests sinistral trajectories for the converging terranes, although extrapolating the shear sense of the suture zone to infer far-field motion must be done with caution. The amalgamation model derived from the chronologic and structural data for the fault zone modifies an existing model of terrane amalgamation and clarifies the definitions of two deformational events (the Nabitah orogeny and the Najd fault system) that are widely represented in the Arabian shield. ?? 2001 Elsevier Science B.V.

  16. Zone heating for fluidized bed silane pyrolysis

    NASA Technical Reports Server (NTRS)

    Iya, Sridhar K. (Inventor)

    1987-01-01

    An improved heated fluidized bed reactor and method for the production of high purity polycrystalline silicon by silane pyrolysis wherein silicon seed particles are heated in an upper heating zone of the reactor and admixed with particles in a lower reaction zone, in which zone a silane-containing gas stream, having passed through a lower cooled gas distribution zone not conducive to silane pyrolysis, contacts the heated seed particles whereon the silane is heterogeneously reduced to silicon.

  17. INEEL Vadose Zone Research Park

    NASA Astrophysics Data System (ADS)

    Heath, G.; Hull, L.; Ansley, S.; Versteeg, R.; Scott, C.; Street, L.

    2003-12-01

    The Vadose Zone Research Park was developed to address mission critical issues related to operations, waste management, and environmental restoration at U. S. Department of Energy (DOE) sites that are located over thick vadose zones. The research park provides instrumentation and facilities for scientists to address vadose zone processes that are important in assessing operational activities, remedial measures, and long-term stewardship of DOE lands. The park, at the Idaho National Engineering and Environmental Laboratory (INEEL), is strategically located along the Big Lost River, an intermittent river, and around two new percolation ponds. This location provides the opportunity to study variable recharge from the river, continuous recharge from the ponds, and the interactions between the two sources. Drilling began in September 2000 and was completed in June 2001. Thirty one wells and instrumented boreholes have been installed at the park to monitor perched water, measure moisture movement, collect water and gas samples, and study intra-well geophysical properties. Nine of the boreholes, ranging in depth from 150 ft to 504 ft below land surface (bls), are instrumented to monitor moisture in the vadose zone. Instruments include: tensiometers, moisture content sensors, suction lysimeters, temperature sensors, gas ports and electrodes for electrical resistance tomography. Electrodes are evenly spaced throughout the borehole with hydrologic instruments concentrated in and near the sedimentary interbeds-discontinuous layers of silts and clays that occur between some basalt flows. Eighteen monitoring wells, ranging in depth from 60 ft to 250 ft bls, are completed with 4 or 6 inch PVC casing, and generally include an electrical resistivity electrode array attached to the casing. Three bore holes are constructed for testing cross-hole ground penetrating radar as well as for testing new nuclear logging tools being designed at the INEEL. The remaining borehole contains only

  18. Microbial oceanography of anoxic oxygen minimum zones.

    PubMed

    Ulloa, Osvaldo; Canfield, Donald E; DeLong, Edward F; Letelier, Ricardo M; Stewart, Frank J

    2012-10-01

    Vast expanses of oxygen-deficient and nitrite-rich water define the major oxygen minimum zones (OMZs) of the global ocean. They support diverse microbial communities that influence the nitrogen economy of the oceans, contributing to major losses of fixed nitrogen as dinitrogen (N(2)) and nitrous oxide (N(2)O) gases. Anaerobic microbial processes, including the two pathways of N(2) production, denitrification and anaerobic ammonium oxidation, are oxygen-sensitive, with some occurring only under strictly anoxic conditions. The detection limit of the usual method (Winkler titrations) for measuring dissolved oxygen in seawater, however, is much too high to distinguish low oxygen conditions from true anoxia. However, new analytical technologies are revealing vanishingly low oxygen concentrations in nitrite-rich OMZs, indicating that these OMZs are essentially anoxic marine zones (AMZs). Autonomous monitoring platforms also reveal previously unrecognized episodic intrusions of oxygen into the AMZ core, which could periodically support aerobic metabolisms in a typically anoxic environment. Although nitrogen cycling is considered to dominate the microbial ecology and biogeochemistry of AMZs, recent environmental genomics and geochemical studies show the presence of other relevant processes, particularly those associated with the sulfur and carbon cycles. AMZs correspond to an intermediate state between two "end points" represented by fully oxic systems and fully sulfidic systems. Modern and ancient AMZs and sulfidic basins are chemically and functionally related. Global change is affecting the magnitude of biogeochemical fluxes and ocean chemical inventories, leading to shifts in AMZ chemistry and biology that are likely to continue well into the future.

  19. Mantle Transition Zone Discontinuities Beneath Alaska

    NASA Astrophysics Data System (ADS)

    Dahm, H. H.; Gao, S. S.; Liu, K. H.; Yang, B.

    2015-12-01

    The 410 and 660 km discontinuities (d410 and d660) beneath Alaska and adjacent areas are imaged by stacking radial receiver functions recorded by about 400 broadband seismic stations with up to 30 years of recording period, using the 1D IASP91 earth model. Significant and spatially systematic variations in the apparent depths of the d410 and d660 are observed. The mean apparent depth of d410 and d660 for the entire study area is 416±1.87 km and 664±1.83 km, respectively. The variations of the apparent depths of d410 and d660 result in a complex mantle transition zone (MTZ) structure. Central and south-central Alaska are characterized by a normal MTZ thickness, suggesting that the subducting Pacific slab does not thermally affect the upper MTZ. Beneath the Yakutat microplate, a complex MTZ structure is observed with an overall thin MTZ thickness, coinciding with a low velocity zone and thin lithospheric thickness revealed by previous seismic tomography and receiver function studies. Two large regions with hot MTZ are mapped beneath NNW and NNE Alaska with abnormal temperature ranges between +360 and +390 °K. Despite of the complexity of the MTZ structure beneath Alaska, the mean MTZ thickness for the entire Alaskan orocline is 247 ±2.76 km, suggesting normal MTZ temperature on average. For the majority of the areas, our study shows that lateral upper mantle velocity variations contribute the bulk of the observed apparent undulations of the MTZ discontinuities.

  20. Evolution of a Subduction Zone

    NASA Astrophysics Data System (ADS)

    Noack, Lena; Van Hoolst, Tim; Dehant, Veronique

    2014-05-01

    The purpose of this study is to understand how Earth's surface might have evolved with time and to examine in a more general way the initiation and continuance of subduction zones and the possible formation of continents on an Earth-like planet. Plate tectonics and continents seem to influence the likelihood of a planet to harbour life, and both are strongly influenced by the planetary interior (e.g. mantle temperature and rheology) and surface conditions (e.g. stabilizing effect of continents, atmospheric temperature), but may also depend on the biosphere. Employing the Fortran convection code CHIC (developed at the Royal Observatory of Belgium), we simulate a subduction zone with a pre-defined weak zone (between oceanic and continental crust) and a fixed plate velocity for the subducting oceanic plate (Quinquis et al. in preparation). In our study we first investigate the main factors that influence the subduction process. We simulate the subduction of an oceanic plate beneath a continental plate (Noack et al., 2013). The crust is separated into an upper crust and a lower crust. We apply mixed Newtonian/non-Newtonian rheology and vary the parameters that are most likely to influence the subduction of the ocanic plate, as for example density of the crust/mantle, surface temperature, plate velocity and subduction angle. The second part of our study concentrates on the long-term evolution of a subduction zone. Even though we model only the upper mantle (until a depth of 670km), the subducted crust is allowed to flow into the lower mantle, where it is no longer subject to our investigation. This way we can model the subduction zone over long time spans, for which we assume a continuous inflow of the oceanic plate into the investigated domain. We include variations in mantle temperatures (via secular cooling and decay of radioactive heat sources) and dehydration of silicates (leading to stiffening of the material). We investigate how the mantle environment influences

  1. Coastal-zone biogeochemical dynamics under global warming

    SciTech Connect

    Mackenzie, F.T.; Ver, L.M.; Lerman, A.

    2000-03-01

    The coastal zone, consisting of the continental shelves to a depth of 200 meters, including bays, lagoons, estuaries, and near-shore banks, is an environment that is strongly affected by its biogeochemical and physical interactions with reservoirs in the adjacent domains of land, atmosphere, open ocean, and marine sediments. Because the coastal zone is smaller in volume and area coverage relative to the open ocean, it traditionally has been studied as an integral part of the global oceans. In this paper, the authors show by numerical modeling that it is important to consider the coastal zone as an entity separate from the open ocean in any assessment of future Earth-system response under human perturbation. Model analyses for the early part of the 21st century suggest that the coastal zone plays a significant modifying role in the biogeochemical dynamics of the carbon cycle and the nutrient cycles coupled to it. This role is manifested in changes in primary production, storage, and/or export of organic matter, its remineralization, and calcium carbonate precipitation--all of which determine the state of the coastal zone with respect to exchange of CO{sub 2} with the atmosphere. Under a scenario of future reduced or complete cessation of the thermohaline circulation (THC) of the global oceans, coastal waters become an important sink for atmospheric CO{sub 2}, as opposed to the conditions in the past and present, when coastal waters are believed to be a source of CO{sub 2} to the atmosphere. Profound changes in coastal-zone primary productivity underscore the important role of phosphorus as a limiting nutrient. In addition, calculations indicate that the saturation state of coastal waters with respect to carbonate minerals will decline by {approximately}15% by the year 2030. Any future slowdown in the THC of the oceans will increase slightly the rate of decline in saturation state.

  2. Lithification facilitates frictional instability in argillaceous subduction zone sediments

    NASA Astrophysics Data System (ADS)

    Trütner, Sebastian; Hüpers, Andre; Ikari, Matt J.; Yamaguchi, Asuka; Kopf, Achim J.

    2015-12-01

    Previous work suggests that in subduction zones, the onset of large earthquake nucleation at depths > ~ 5-10 km is likely driven by a combination of factors associated with the process of lithification. At these depths, lithification processes affect the entire fault system by modifying the mechanical properties of both the plate boundary fault zone and the wall-rock. To test the hypothesis that lithification of subduction zone sediments produces rocks capable of earthquake nucleation via diagenesis and low-grade metamorphism, we conducted friction experiments on fossil subduction zone sediments recovered from exposures in the Shimanto Belt in SW Japan. These meta-sediments represent accreted and subducted material which has experienced maximum temperatures of 125 to 225 °C, which are representative of seismogenic depths along the active Nankai subduction megathrust in the foreland of the Shimanto Belt. We find that intact Shimanto rock samples, which preserve the influence of diagenetic and metamorphic processes, exhibit the potential for unstable slip under in-situ pressure conditions. Powdered versions of the same samples tested under the same conditions exhibit only velocity-strengthening friction, thus demonstrating that destroying the lithification state also removes the potential for unstable slip. Using advanced porosity loss to quantify the lithification process, we demonstrate that increased velocity weakening correlates with increasingly advanced lithification. In combination with documented frictionally stable behavior of subduction zone sediments from shallower depths, our results provide evidence that the sediment lithification hypothesis can explain the depth-dependent onset of large earthquake nucleation along subduction zone megathrusts.

  3. 46 CFR 76.33-5 - Zoning.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Smoke Detecting System, Details § 76.33-5 Zoning. (a) The smoke detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) The smoke detecting zone shall not...

  4. 46 CFR 76.33-5 - Zoning.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Smoke Detecting System, Details § 76.33-5 Zoning. (a) The smoke detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) The smoke detecting zone shall not...

  5. 46 CFR 76.33-5 - Zoning.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Smoke Detecting System, Details § 76.33-5 Zoning. (a) The smoke detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) The smoke detecting zone shall not...

  6. 46 CFR 76.33-5 - Zoning.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Smoke Detecting System, Details § 76.33-5 Zoning. (a) The smoke detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) The smoke detecting zone shall not...

  7. 46 CFR 76.33-5 - Zoning.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Smoke Detecting System, Details § 76.33-5 Zoning. (a) The smoke detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) The smoke detecting zone shall not...

  8. 49 CFR 71.10 - Pacific zone.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Time Act of 1966 and Pub. L. 97-449, 15 U.S.C. 260-264; 49 CFR 1.59(a)). ... 49 Transportation 1 2014-10-01 2014-10-01 false Pacific zone. 71.10 Section 71.10 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.10 Pacific zone. The...

  9. 49 CFR 71.10 - Pacific zone.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Time Act of 1966 and Pub. L. 97-449, 15 U.S.C. 260-264; 49 CFR 1.59(a)). ... 49 Transportation 1 2012-10-01 2012-10-01 false Pacific zone. 71.10 Section 71.10 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.10 Pacific zone. The...

  10. 49 CFR 71.10 - Pacific zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Time Act of 1966 and Pub. L. 97-449, 15 U.S.C. 260-264; 49 CFR 1.59(a)). ... 49 Transportation 1 2010-10-01 2010-10-01 false Pacific zone. 71.10 Section 71.10 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.10 Pacific zone. The...

  11. 47 CFR 73.609 - Zones.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Zones. 73.609 Section 73.609 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Television Broadcast Stations § 73.609 Zones. (a) For the purpose of allotment and assignment, the United States is divided into three zones as follows:...

  12. Technical Education in the Enterprise Zone.

    ERIC Educational Resources Information Center

    Friedman, Howard

    Support is growing for the concept of the enterprise zone. Congress has before it a bill, the Enterprise Zone Tax Act of 1982, that would provide incentives and create a climate in which entrepreneurs and business executives would locate businesses in areas of pervasive poverty and unemployment. A potential urban enterprise zone in New York City…

  13. 47 CFR 73.609 - Zones.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Zones. 73.609 Section 73.609 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Television Broadcast Stations § 73.609 Zones. (a) For the purpose of allotment and assignment, the United States is divided into three zones as follows:...

  14. Do "Some" Enterprise Zones Create Jobs?

    ERIC Educational Resources Information Center

    Kolko, Jed; Neumark, David

    2010-01-01

    We study how the employment effects of enterprise zones vary with their location, implementation, and administration, based on evidence from California. We use new establishment-level data and geographic mapping methods, coupled with a survey of enterprise zone administrators. Overall, the evidence indicates that enterprise zones do not increase…

  15. Affectional Patterns of Adolescents.

    ERIC Educational Resources Information Center

    O'Donnell, William J.

    1979-01-01

    This study sought to determine if there is a shift with age in affection (1) from parents to friends, (2) from one parent to the other, and (3) from same-sex to opposite-sex friends. Subjects, eighth graders and eleventh graders, completed the Measurement of Family Affective Structure. (Author)

  16. Affective Involvement Instrument.

    ERIC Educational Resources Information Center

    Lemlech, Johanna K.

    1970-01-01

    The Affective Involvement Instrument (AII) describes and classifies affective involvement in the process of decision-making as it occurs during classroom activities such as role-playing or group discussions. The thirty-celled instrument behaviorizes the six processes involved in decision-making and combines them with the taxonomic levels of the…

  17. Analysis of laser beam weldability of Inconel 738 superalloy

    SciTech Connect

    Egbewande, A.T.; Buckson, R.A.; Ojo, O.A.

    2010-05-15

    The susceptibility of pre-weld heat treated laser beam welded IN 738 superalloy to heat affected zone (HAZ) cracking was studied. A pre-weld heat treatment that produced the minimal grain boundary liquation resulted in a higher level of cracking compared to those with more intergranular liquation. This deviation from the general expectation of influence of intergranular liquation extent on HAZ microfissuring is attributable to the reduction in the ability of the base alloy to accommodate welding tensile stress that accompanied a pre-weld heat treatment condition designed to minimize intergranular liquation. Furthermore, in contrast to what has been generally reported in other nickel-based superalloys, a decrease in laser welding speed resulted in increased HAZ cracking in the IN 738, which can be attributed to exacerbated process instability at lower welding speeds.

  18. Characterization of a Friction Stir Weld in Aluminum Alloy 7055 Using Microhardness, Electrical Conductivity, and Differential Scanning Calorimetry (DSC)

    NASA Astrophysics Data System (ADS)

    Bush, Ralph; Kiyota, Michelle; Kiyota, Catherine

    2016-07-01

    Optical microscopy, microhardness, electrical conductivity, and differential scanning calorimetry (DSC) were used to characterize the microstructure, hardness, and precipitate structure as a function of position in a friction stir weld, naturally aged for 10 years, in aluminum alloy 7055. Results are shown for the as-welded/naturally aged condition and for a weld that was post-aged using a -T76 regimen. The grain structure and microhardness results reveal the expected central recrystallized region, a thermo-mechanical affected zone (TMAZ), and heat-affected zone (HAZ) with typical changes in microhardness. DSC scans for the as-welded/naturally aged condition indicate a precipitate structure similar to that of a naturally aged condition in the central recrystallized region. Maximum precipitate coarsening and overaging occurs near the TMAZ/HAZ boundary with reduced precipitate dissolution and coarsening as the distance from the weld increases. The post-weld aging resulted in the transformation of GP zones to more stable precipitates plus coarsening of the more stable η' and η precipitates. A combination of DSC testing and CALPHAD calculations allowed calculation of precipitate volume fraction in the HAZ. The precipitate volume fraction decreased monotonically from 0.052 in the baseline material to 0.044 at the TMAZ/HAZ interface.

  19. An Algorithm for Evaluating Fresnel-Zone Textural Roughness for Seismic Facies Interpretation

    NASA Astrophysics Data System (ADS)

    Di, H.; Gao, D.

    2014-12-01

    In reflection seismic interpretation, a 1-D convolutional model is commonly used to interpret amplitude variations based on the geometric ray theory assuming seismic wave to reflect at a reflection point; however, the propagation of seismic waves actually occurs in a finite zone around the geometric ray path and gets reflected from a zone known as Fresnel zone. The collected signal at the surface turns out to be the superposition of reflections from within the Fresnel zone, which is a function of texture. Generally, for a rough texture such as sandstone, the dominant reflection is from the zone margin, while for a smooth texture such as marine shale, the dominant reflection is from the zone center. Based on this concept, Fresnel-zone texture directly affects amplitude variations with offset (AVO), azimuth (AVAZ), and frequency (AVF). Here we develop a computer algorithm for evaluating Fresnel-zone textural roughness. The algorithm starts with dividing the Fresnel zone into a set of micro-zones. It then builds an initial texture model to be convolved with an extracted wavelet. By comparing the synthetic signal from a Fresnel zone to the real seismic signal within an analysis window at a target location, the model is adjusted and updated until both synthetic and real signals match best. The roughness is evaluated as the correlation coefficient between the generated texture model within the Fresnel zone and the ideal model for a rough texture medium. Our new algorithm is applied to a deep-water 3D seismic volume over offshore Angola, west Africa. The results show that a rough texture is associated with channel sands, whereas a smooth texture with marine shale.

  20. 30 CFR 250.235 - If a State objects to the EP's coastal zone consistency certification, what can I do?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false If a State objects to the EP's coastal zone... SHELF Plans and Information Review and Decision Process for the Ep § 250.235 If a State objects to the EP's coastal zone consistency certification, what can I do? If an affected State objects to...

  1. Pinot noir wine volatile and anthocyanin composition under different levels of vine fruit zone leaf removal.

    PubMed

    Feng, Hui; Skinkis, Patricia A; Qian, Michael C

    2017-01-01

    The impacts of fruit zone leaf removal on volatile and anthocyanin compositions of Pinot noir wine were investigated over two growing seasons. Wine volatiles were analyzed by multiple techniques, including headspace solid phase microextraction-GC-MS (HS-SPME-GC-MS), headspace-GC-FID (HS-GC-FID) and stir bar sorptive extraction-GC-MS (SBSE-GC-MS). Fruit zone leaf removal affected the concentration of many grape-derived volatile compounds such as terpene alcohols and C13-norisoprenoids in wine, although the degree of impact depended on the vintage year and severity of leaf removal. Fruit zone leaf removal resulted in greater concentrations of linalool, α-terpineol and β-damascenone but had no impact on other terpene alcohols or β-ionone. Fruit zone leaf removal had no consistent impact on C6 alcohols, volatile phenols, lactones, fermentation-derived alcohols, acids, or most esters. Fruit zone leaf removal increased anthocyanins in final wine.

  2. 77 FR 29898 - Safety Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ... Detroit Zone AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce the safety zones for annual fireworks events in the Captain of the Port Detroit zone... the Port Detroit Zone, at the following times for the following events: (1) Put-In-Bay Fourth of...

  3. 76 FR 70342 - Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-14

    .../2011 USCG-2011-0213 Erie Basin, NY Safety Zone (Part 165)... 6/11/2011 USCG-2011-0217 Knoxville, TN... Safety Zone (Part 165)... 4/12/2011 USCG-2011-0273 Lake Michigan Safety and Security Zone 4/14/2011 (Part.../28/2011 USCG-2011-0282 Lake Michigan Safety and Security Zone 4/27/2011 (Part 165). ]...

  4. 33 CFR 165.T09-0263 - Safety zone; Red River Safety Zone, Red River, MN.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Safety zone; Red River Safety Zone, Red River, MN. 165.T09-0263 Section 165.T09-0263 Navigation and Navigable Waters COAST GUARD... § 165.T09-0263 Safety zone; Red River Safety Zone, Red River, MN. (a) Location. The following area is...

  5. Vadose zone monitoring for hazardous waste sites

    SciTech Connect

    Everett, L.G.; Wilson, L.G.; Hoylman, E.W.

    1983-10-01

    This book describes the applicability of vadose zone monitoring techniques to hazardous waste site investigations. More than 70 different sampling and nonsampling vadose zone monitoring techniques are described in terms of their advantages and disadvantages. Physical, chemical, geologic, topographic, geohydrologic, and climatic constraints for vadose zone monitoring are quantitatively determined. Vadose zone monitoring techniques are categorized for premonitoring, active, and postclosure site assessments. Waste disposal methods are categorized for piles, landfills, impoundments, and land treatment. Conceptual vadose zone monitoring approaches are developed for specific waste disposal method categories.

  6. In-Situ Phase Mapping and Direct Observations of Phase Transformations During Arc Welding of 1045 Steel

    SciTech Connect

    Elmer, J; Palmer, T

    2005-09-13

    In-situ Spatially Resolved X-Ray Diffraction (SRXRD) experiments were performed during gas tungsten arc (GTA) welding of AISI 1045 C-Mn steel. Ferrite ({alpha}) and austenite ({gamma}) phases were identified and quantified in the weld heat-affected zone (HAZ) from the real time x-ray diffraction data. The results were compiled along with weld temperatures calculated using a coupled thermal fluids weld model to create a phase map of the HAZ. This map shows the {alpha} {yields} {gamma} transformation taking place during weld heating and the reverse {gamma} {yields} {alpha} transformation taking place during weld cooling. Superheating is required to complete the {alpha} {yields} {gamma} phase transformation, and the amount of superheat above the A3 temperature was shown to vary with distance from the centerline of the weld. Superheat values as high as 250 C above the A3 temperature were observed at heating rates of 80 C/s. The SRXRD experiments also revealed details about the {gamma} phase not observable by conventional techniques, showing that {gamma} is present with two distinct lattice parameters as a result of inhomogeneous distribution of carbon and manganese in the starting pearlitic/ferritic microstructure. During cooling, the reverse {gamma} {yields} {alpha} phase transformation was shown to depend on the HAZ location. In the fine grained region of the HAZ, at distances greater than 2 mm from the fusion line, the {gamma} {yields} {alpha} transformation begins near the A3 temperature and ends near the A1 temperature. In this region of the HAZ where the cooling rates are below 40 C/s, the transformation occurs by nucleation and growth of pearlite. For HAZ locations closer to the fusion line, undercoolings of 200 C or more below the A1 temperature are required to complete the {gamma} {yields} {alpha} transformation. In this region of the HAZ, grain growth coupled with cooling rates in excess of 50 C/s causes the transformation to occur by a bainitic mechanism.

  7. [Affect and mimetic behavior].

    PubMed

    Zepf, S; Ullrich, B; Hartmann, S

    1998-05-01

    The relationship between facial expression and experienced affect presents many problems. The two diametrically opposed positions proposing solutions to this problem are exemplified using the conceptions of Mandler u. Izard. The underlying premises of both conceptions still prevail in various forms. The authors reject the concepts according to which facial expression is merely correlated to the affects (see Mandler 1975) as well as the view that facial expression controls the affects (see Izard 1977). The relationship between affect and facial expression is reexamined, subjecting it to a semiotic, essentially semantic analysis similar to the Ogden and Richards' language and meaning approach. This analysis involves a critical discussion of Scherer's attempt of a purely communicational interpretation using Bühler's organon model. In the author's approach, facial expression is seen not simply as a system of signals, but as a system of representative signs which signify the affects and refer to the emotive meaning of things for the subject. The authors develop the thesis that human beings are not born simply with the ability to speak, but also with the abstract possibility of performing facial expressions. This ability develops by way of coordinating patterns of expressions, which are presumably phylogenetically determined, with affects that take on a socially determined individual form, similar to language acquisition during socialisation. The authors discuss the methodological implications arising for studies investigating the affective meaning of facial expressions. PMID:9632951

  8. Holdridge life zone physical inconsistency

    NASA Astrophysics Data System (ADS)

    Martínez, A., Sr.; Ochoa, A.

    2015-12-01

    Life zones is a very used classification system, developed by L.R. Holdridge in 1967, used to discern why plants have different adaptation mechanism to their surrounding environment. In this paper, the relation between potential evapotranspiration rate (ETr ), anual precipitation (P ) and biotemperature (Tb ) in the Holdridge triangle, is parametrized (P = (500/9)*ETr) to evaluate if the rain process is conserved in Colombia. Further, an adiabatic ascent of air with diurnal and interannual variability, and cluster analysis is view as a classification example of the advantage of using physical process to evaluate the plants adaptation mechanisms . The most inconsistency life zones are situated in the rainiest places of Colombian pacific costs in tropical latitudinal region, are non-exist places in holdridge triangle with annual biotemperature higher than 26◦ C, annual precipitation about 10.000mm and annual potential evapotranspiration rate about 0.1. The difference between Holdridge predicted precipitation and the precipitation measured with TRMM are about 5.000mm in these places. Classification systems based on an annual average, do not stablish adaptation as a function of diurnal variability, for example, the difference between valley sides vegetation could not being determined. This kind of limitations, added to a validation procces and the auscence of a physic procces in the variable interaction, make the Holdridge Life Zones a very useful tool, but physically inconsistent for caracterice vegetation as a function of precipitation. The rain process is very complex, depend of mass and energy exchanges and is still a controversial topic in atmospheric modeling, as a biotic pump.

  9. Architecture of small-scale fault zones in the context of the Leinetalgraben Fault System

    NASA Astrophysics Data System (ADS)

    Reyer, Dorothea; Philipp, Sonja L.

    2010-05-01

    Understanding fault zone properties in different geological settings is important to better assess the development and propagation of faults. In addition this allows better evaluation and permeability estimates of potential fault-related geothermal reservoirs. The Leinetalgraben fault system provides an outcrop analogue for many fault zones in the subsurface of the North German Basin. The Leinetalgraben is a N-S-trending graben structure, initiated in the Jurassic, in the south of Lower Saxony and as such part of the North German Basin. The fault system was reactivated and inverted during Alpine compression in the Tertiary. This complex geological situation was further affected by halotectonics. Therefore we can find different types of fault zones, that is normal, reverse, strike-slip an oblique-slip faults, surrounding the major Leinetalgraben boundary faults. Here we present first results of structural geological field studies on the geometry and architecture of fault zones in the Leinetalgraben Fault System in outcrop-scale. We measured the orientations and displacements of 17 m-scale fault zones in limestone (Muschelkalk) outcrops, the thicknesses of their fault cores and damage zones, as well as the fracture densities and geometric parameters of the fracture systems therein. We also analysed the effects of rock heterogeneities, particularly stiffness variations between layers (mechanical layering) on the propagation of natural fractures and fault zones. The analysed fault zones predominantly show similar orientations as the major fault zones they surround. Other faults are conjugate or perpendicular to the major fault zones. The direction of predominant joint strike corresponds to the orientation of the fault zones in the majority of cases. The mechanical layering of the limestone and marlstone stratification obviously has great effects on fracture propagation. Already thin layers (mm- to cm-scale) of low stiffness - here marl - seem to suffice to change the

  10. Effects of Terrestrial Buffer Zones on Amphibians on Golf Courses

    PubMed Central

    Puglis, Holly J.; Boone, Michelle D.

    2012-01-01

    A major cause of amphibian declines worldwide is habitat destruction or alteration. Public green spaces, such as golf courses and parks, could serve as safe havens to curb the effects of habitat loss if managed in ways to bolster local amphibian communities. We reared larval Blanchard's cricket frogs (Acris blanchardi) and green frogs (Rana clamitans) in golf course ponds with and without 1 m terrestrial buffer zones, and released marked cricket frog metamorphs at the golf course ponds they were reared in. Larval survival of both species was affected by the presence of a buffer zone, with increased survival for cricket frogs and decreased survival for green frogs when reared in ponds with buffer zones. No marked cricket frog juveniles were recovered at any golf course pond in the following year, suggesting that most animals died or migrated. In a separate study, we released cricket frogs in a terrestrial pen and allowed them to choose between mown and unmown grass. Cricket frogs had a greater probability of using unmown versus mown grass. Our results suggest that incorporating buffer zones around ponds can offer suitable habitat for some amphibian species and can improve the quality of the aquatic environment for some sensitive local amphibians. PMID:22761833

  11. Origin of a major cross-element zone: Moroccan Rif

    SciTech Connect

    Morley, C.K.

    1987-08-01

    Alpine age (Oligocene-Miocene) deformation in the western Mediterranean formed the Rif mountain belt of northern Morocco. A linear east-northeast-west-southwest trend of cross elements from Jebah (Mediterranean coast) to Arbaoua (near the Atlantic coast) extends through several thrust sheets in the western Rif. The cross elements are manifest as a lateral ramp, the northern limit of a large culmination, and they affect syntectonic turbidite sandstone distribution. Gravity anomalies indicate that the cross-element zone is coincident with a transition zone from normal thickness to thinner continental crust. It is suggested that an early Mesozoic strike-slip fault system related to rifting of North America from North Africa caused a strong east-northeast-west-southwest, basement block-fault trend to form on the normal thickness side of the thick-to-thin continental crustal transition zone. This trend later influenced the position of the Alpine age cross-element zone that traverses several different Mesozoic and Tertiary basins, inverted during the Alpine deformation.

  12. Effects of terrestrial buffer zones on amphibians on golf courses.

    PubMed

    Puglis, Holly J; Boone, Michelle D

    2012-01-01

    A major cause of amphibian declines worldwide is habitat destruction or alteration. Public green spaces, such as golf courses and parks, could serve as safe havens to curb the effects of habitat loss if managed in ways to bolster local amphibian communities. We reared larval Blanchard's cricket frogs (Acris blanchardi) and green frogs (Rana clamitans) in golf course ponds with and without 1 m terrestrial buffer zones, and released marked cricket frog metamorphs at the golf course ponds they were reared in. Larval survival of both species was affected by the presence of a buffer zone, with increased survival for cricket frogs and decreased survival for green frogs when reared in ponds with buffer zones. No marked cricket frog juveniles were recovered at any golf course pond in the following year, suggesting that most animals died or migrated. In a separate study, we released cricket frogs in a terrestrial pen and allowed them to choose between mown and unmown grass. Cricket frogs had a greater probability of using unmown versus mown grass. Our results suggest that incorporating buffer zones around ponds can offer suitable habitat for some amphibian species and can improve the quality of the aquatic environment for some sensitive local amphibians.

  13. Prioritising coastal zone management issues through fuzzy cognitive mapping approach.

    PubMed

    Meliadou, Aleka; Santoro, Francesca; Nader, Manal R; Dagher, Manale Abou; Al Indary, Shadi; Salloum, Bachir Abi

    2012-04-30

    Effective public participation is an essential component of Integrated Coastal Zone Management implementation. To promote such participation, a shared understanding of stakeholders' objectives has to be built to ultimately result in common coastal management strategies. The application of quantitative and semi-quantitative methods involving tools such as Fuzzy Cognitive Mapping is presently proposed for reaching such understanding. In this paper we apply the Fuzzy Cognitive Mapping tool to elucidate the objectives and priorities of North Lebanon's coastal productive sectors, and to formalize their coastal zone perceptions and knowledge. Then, we investigate the potential of Fuzzy Cognitive Mapping as tool for support coastal zone management. Five round table discussions were organized; one for the municipalities of the area and one for each of the main coastal productive sectors (tourism, industry, fisheries, agriculture), where the participants drew cognitive maps depicting their views. The analysis of the cognitive maps showed a large number of factors perceived as affecting the current situation of the North Lebanon coastal zone that were classified into five major categories: governance, infrastructure, environment, intersectoral interactions and sectoral initiatives. Furthermore, common problems, expectations and management objectives for all sectors were exposed. Within this context, Fuzzy Cognitive Mapping proved to be an essential tool for revealing stakeholder knowledge and perception and understanding complex relationships. PMID:22325583

  14. Effects of remediation amendments on vadose zone microorganisms

    SciTech Connect

    Miller, Hannah M.; Tilton, Fred A.

    2012-08-10

    Surfactant-based foam delivery technology has been studied to remediate Hanford 200 area deep vadose zone sediment. However, the surfactants and remediation amendments have an unknown effect on indigenous subsurface microorganisms. Microbial populations are important factors to consider in remediation efforts due to their potential to alter soil geochemistry. This project focuses on measuring microbial metabolic responses to remediation amendments in batch and column studies using Deep Vadose Zone Sediments. Initial studies of the microbes from Hanford 200 area deep vadose zone sediment showed surfactants sodium dodecyl sulfate (SDS) and cocamidopropyl betaine (CAPB) and remediation amendment calcium polysulfide (CPS) had no affect on microbial growth using BiologTM Ecoplates. To move towards a more realistic field analog, soil columns were packed with Hanford 200 Area sediment. Once microbial growth in the column was verified by observing growth of the effluent solution on tryptic soy agar plates, remedial surfactants were injected into the columns, and the resulting metabolic diversity was measured. Results suggest surfactant sodium dodecyl sulfate (SDS) stimulates microbial growth. The soil columns were also visualized using X-ray microtomography to inspect soil packing and possibly probe for evidence of biofilms. Overall, BiologTM Ecoplates provide a rapid assay to predict effects of remediation amendments on Hanford 200 area deep vadose zone microorganisms.

  15. Coastal zone color scanner retrospective

    NASA Astrophysics Data System (ADS)

    Mitchell, B. Greg

    1994-04-01

    The following special section of the Journal of Geophysical Research is dedicated to a retrospective of scientific studies using the coastal zone color scanner (CZCS) instrument. The CZCS was launched in late 1978 aboard the Nimbus 7 satellite as a "proof-of-concept" instrument to demonstrate the feasibility of using satellite platforms to monitor the distribution of oceanic phytoplankton in the world's oceans. It provided data until the middle of 1986. Phytoplankton primary production contributes approximately one half of the global biospheric fixation of organic matter by photosynthesis, thereby forming the base of the oceanic food web and providing a major sink for atmospheric CO2.

  16. Contrasting origins of breached relay zone geometries

    NASA Astrophysics Data System (ADS)

    Conneally, J.; Childs, C.; Walsh, J. J.

    2014-01-01

    Relay zones accommodate transfer of displacement between pairs of adjacent segments of a fault array that become linked to form a through-going fault as displacement increases. 3D geometric and kinematic analysis of two vertically aligned relay zones, that form a complex boundary between two fault segments, generally support this model of relay zone growth but they also highlight some departures from this scheme. The two seismically mapped relay zones, although separated vertically by 100 m, were synchronously active over most of their development history. A causal relationship between them is proposed with the geometric complexity arising from the formation of the lower relay zone triggering the formation of the upper. The lower relay zone is now breached but originally formed a hole within the fault surface up to throws of ca. 50 m. The upper relay zone displays both breached and intact relay zone geometries at different structural levels demonstrating that relay zone breaching is a protracted rather than geologically instantaneous process. Geometrically the lower part of this structure resembles a breached relay zone, but it formed by propagation of a splay fault from a pre-existing bend to enclose an intervening and steepening ramp, a growth scheme which is the opposite of conventional relay zone models.

  17. Zoned heating and air conditioning system

    SciTech Connect

    Beachboard, S.A.

    1987-06-16

    This patent describes a zoned heating and air conditioning system comprising: a central air handling system with an air heating means and an air cooling means and a blower connected to an air duct system; thermostats each have heating and cooling set points, respectively associated with and located in different zones of a building; dampers respectively associated with each building zone positioned in the air duct system. Each damper has an open position allowing air into the respective zone from the duct system and a closed position; relay means for connecting one thermostat to the air handling system upon a call for heating or cooling by one thermostat and disconnecting all other thermostats by connecting one thermostat's connections between the thermostat and air handling system. Only one thermostat is connected to the air handling system at a time and the relay means disconnects one thermostat from the air handling system after one thermostat is satisified; and damper actuating means for unlocking each damper in one building zone responsive actuated by a respective zone thermostat connected to the air handling system by the relay means. The damper actuates means including a damper solenoid for each damper located adjacent each damper and connected to a respective zone thermostat. It unlocks each damper in one building zone responsive to being actuated by the respective zone thermostat and unlocks the dampers in one building zone when one thermostat is actuated while preventing the dampers in another thermostat's building zone from unlocking.

  18. FOAM: NOVEL DELIVERY TECHNOLOGY FOR REMEDIATION OF VADOSE ZONE ENVIRONMENTS

    SciTech Connect

    Jansik, Danielle P.; Wellman, Dawn M.; Mattigod, Shas V.; Zhong, Lirong; Wu, Yuxin; Foote, Martin; Zhang, Z. F.; Hubbard, Susan

    2011-07-05

    Deep vadose zone environments can be a primary source and pathway for contaminant migration to groundwater. These environments present unique characterization and remediation challenges that necessitate scrutiny and research. The thickness, depth, and intricacies of the deep vadose zone, combined with a lack of understanding of the key subsurface processes (e.g., biogeochemical and hydrologic) affecting contaminant migration, make it difficult to create validated conceptual and predictive models of subsurface flow dynamics and contaminant behavior across multiple scales. These factors also make it difficult to design and deploy sustainable remedial approaches and monitor long-term contaminant behavior after remedial actions. Functionally, the methods for addressing contamination must remove and/or reduce transport of contaminants. This problem is particularly challenging in the arid western United States where the vadose zone is hundreds of feet thick, rendering transitional excavation methods exceedingly costly and ineffective. Delivery of remedial amendments is one of the most challenging and critical aspects for all remedy-based approaches. The conventional approach for delivery is through injection of aqueous remedial solutions. However, heterogeneous deep vadose zone environments present hydrologic and geochemical challenges which limit the effectiveness. Because the flow of solution infiltration is dominantly controlled by gravity and suction, injected liquid preferentially percolates through highly permeable pathways, by-passing low-permeability zones which frequently contain the majority of contamination. Moreover, the wetting front can readily mobilize and enhance contaminant transport to the underlying aquifer prior to stabilization. Development of innovative, in-situ technologies may be the only way to meet remedial action objectives and long-term stewardship goals. Surfactants can be used to lower the liquid surface tension and create stabile foams

  19. Compounds affecting cholesterol absorption

    NASA Technical Reports Server (NTRS)

    Hua, Duy H. (Inventor); Koo, Sung I. (Inventor); Noh, Sang K. (Inventor)

    2004-01-01

    A class of novel compounds is described for use in affecting lymphatic absorption of cholesterol. Compounds of particular interest are defined by Formula I: ##STR1## or a pharmaceutically acceptable salt thereof.

  20. Euphotic Zone Study moves forward

    NASA Astrophysics Data System (ADS)

    Denman, Kenneth

    The Global Ocean Euphotic Zone Study (GOEZS), a potential core program of the International Geosphere-Biosphere Programme (IGBP) being planned jointly with the Scientific Committee on Oceanic Research (SCOR), was recently given the go-ahead by IGBP's Scientific Committee to move on to the next level of developing its scientific program.The GOEZS program will focus on the coupled physical, biological, and chemical processes operating in the euphotic zone, which is the ocean surface layer where sufficient light penetrates for photosynthesis by phytoplankton to exceed their metabolic energy losses. The upper ocean is extremely important to understanding the atmosphereocean system because it mediates exchanges of heat, momentum, carbon dioxide, sulphur, and nitrogen between the atmosphere and the ocean interior. For the major greenhouse gas carbon dioxide for example, there is more carbon in the upper ocean than in the whole atmosphere. Essentially all carbon dioxide from the atmosphere that passes from the upper ocean to the ocean interior has been transformed chemically or biologically in the upper ocean. Moreover, the upper ocean is the site of all marine shipping and most recreation and industrial activity and contains the planktonic food chain and most fish stocks.

  1. The Structural Architecture and Tectonic Inheritance of the Vlora-Elbasan Transfer Zone in Albanides-Albania

    NASA Astrophysics Data System (ADS)

    Abus, E. D.; Dilek, Y.

    2014-12-01

    The Albanides in the Balkan Peninsula are part of the Alpine orogenic belt and host one of the most significant oil fields in SE Europe. The late Mesozoic-Cenozoic evolution of the Albanides has been strongly controlled by the relative movements of Adria or Apulia, a microcontinent with a West Gondwana affinity with respect to Eurasia. In northeastern Albania, the Internal Albanides consist of Paleozoic - Jurassic basement rocks, which involved subduction zone tectonics of the Pindos-Mirdita ocean basin. The External Albanides, on the other hand, represent a fold-and-thrust belt with deformation in a broad zone of oblique convergence. This tectonic domain is divided, from east to west, into five major structural zones: the Krasta-Cukali Zone, the Kruja Zone, the Peri-Adriatic Depression, the Ionian Zone, and the Sazani Zone, which is represented by the Apulian platform carbonates. The zone is characterized by NW-SE-running and SW-verging thrust fault systems that involve a thick series of Mesozoic - Tertiary passive margin carbonates, unconformably overlain by Oligocene clastic units. These two tectonic zones are dissected by the NE-SW-striking Vlora-Elbasan Transfer Zone, which extends eastwards into the Internal Albanides, affecting the structural architecture and the tectonic evolution of the entire mountain belt. This fault zone that has been tectonically active from the Triassic to recent have display diapiric structures along it.

  2. Laser Surface Hardening of AISI 1045 Steel

    NASA Astrophysics Data System (ADS)

    Li, Ruifeng; Jin, Yajuan; Li, Zhuguo; Qi, Kai

    2014-09-01

    The study investigates laser surface hardening in the AISI 1045 steel using two different types of industrial laser: a high-power diode laser (HPDL) and a CO2 laser, respectively. The effect of process parameters such as beam power, travel speed on structure, case depth, and microhardness was examined. In most cases, a heat-affected zone (HAZ) formed below the surface; a substantial increase in surface hardness was achieved. In addition, big differences were found between the hardened specimens after HPDL surface hardening and CO2 laser surface hardening. For HPDL, depths of the HAZ were almost equal in total HAZ o, without surface melting. For CO2 laser, the depths changed a lot in the HAZ, with surface melting in the center. To better understand the difference of laser hardening results when use these two types of laser, numerical (ANSYS) analysis of the heat conduction involved in the process was also studied. For HPDL method, a rectangular beam spot and uniform energy distribution across the spot were assumed, while for CO2 laser, a circular beam spot and Gaussian energy distribution were assumed. The results showed that the energy distribution variety altered the thermal cycles of the HAZ dramatically. The rectangular HPDL laser beam spot with uniform energy distribution is much more feasible for laser surface hardening.

  3. The Himalayan Seismogenic Zone: A New Frontier for Earthquake Research

    NASA Astrophysics Data System (ADS)

    Brown, Larry; Hubbard, Judith; Karplus, Marianne; Klemperer, Simon; Sato, Hiroshi

    2016-04-01

    The Mw 7.8 Gorkha, Nepal, earthquake that occurred on April 25 of this year was a dramatic reminder that great earthquakes are not restricted to the large seismogenic zones associated with subduction of oceanic lithosphere. Not only does Himalayan seismogenesis represents important scientific and societal issues in its own right, it constitutes a reference for evaluating general models of the earthquake cycle derived from the studies of the oceanic subduction systems. This presentation reports results of a Mini-Workshop sponsored by the GeoPrisms project that was held in conjunction with the American Geophysical Union on December 15, 2015, designed to organize a new initiative to study the great Himalaya earthquake machine. The Himalayan seismogenic zone shares with its oceanic counterparts a number of fundamental questions, including: a) What controls the updip and downdip limits of rupture? b) What controls the lateral segmentation of rupture zones (and hence magnitude)? c) What is the role of fluids in facilitating slip and or rupture? d) What nucleates rupture (e..g. asperities?)? e) What physical properties can be monitored as precursors to future events? f) How effectively can the radiation pattern of future events be modeled? g) How can a better understanding of Himalayan rupture be translated into more cost effective preparations for the next major event in this region? However the underthrusting of continental, as opposed to oceanic, lithosphere in the Himalayas frames these questions in a very different context: h) How does the greater thickness and weaker rheology of continental crust/lithosphere affect locking of the seismogenic zone? i) How does the different thermal structure of continental vs oceanic crust affect earthquake geodynamics? j) Are fluids a significant factor in intercontinental thrusting? k) How does the basement morphology of underthrust continental crust affect locking/creep, and how does it differ from the oceanic case? l) What is the

  4. Control of climate and litter quality on leaf litter decomposition in different climatic zones.

    PubMed

    Zhang, Xinyue; Wang, Wei

    2015-09-01

    Climate and initial litter quality are the major factors influencing decomposition rates on large scales. We established a comprehensive database of terrestrial leaf litter decomposition, including 785 datasets, to examine the relationship between climate and litter quality and evaluate the factors controlling decomposition on a global scale, the arid and semi-arid (AS) zone, the humid middle and humid low (HL) latitude zones. Initial litter nitrogen (N) and phosphorus (P) concentration only increased with mean annual temperature (MAT) in the AS zone and decreased with mean annual precipitation (MAP) in the HL zone. Compared with nutrient content, MAT imposed less effect on initial litter lignin content than MAP. MAT were the most important decomposition driving factors on a global scale as well as in different climatic zones. MAP only significantly affected decomposition constants in AS zone. Although litter quality parameters also showed significant influence on decomposition, their importance was less than the climatic factors. Besides, different litter quality parameters exerted significant influence on decomposition in different climatic zones. Our results emphasized that climate consistently exerted important effects on decomposition constants across different climatic zones.

  5. Assessment of Spatial Distribution of Growth in the Elongation Zone of Grass Leaf Blades 1

    PubMed Central

    Schnyder, Hans; Nelson, Curtis J.; Coutts, John H.

    1987-01-01

    Knowledge about the spatial distribution of growth is essential for understanding the leaf growth process. In grasses the elongation zone is located at the base of the leaf blade and is enclosed by sheaths of older leaves. Assessment of spatial growth distribution, therefore, necessitates use of a destructive method. We used a fine needle to make holes through bases of tillers at the location of the leaf elongation zone of tall fescue (Festuca arundinacea Schreb.), then measured the displacement of the holes after a 6 or 24 h interval. Needle holes caused a 22 to 41% decrease in daily leaf elongation so experiments were conducted to investigate if the spatial distribution of growth in the elongation zone was altered. Leaf elongation rate was reduced similarly when needle holes were made within or above the zone where cell elongation occurs. Distribution of elongation within the zone was the same when estimated by displacement of needle holes or ink marks placed on the epidermis of the elongation zone after surrounding tissue had been removed. Making holes at different locations within the elongation zone did not differentially affect the relative contribution of the damaged or undamaged parts to leaf elongation. These findings demonstrate that needle holes or ink marks in paired leaves can be used to estimate the relative distribution of growth in the elongation zone of undamaged tall fescue leaf blades. PMID:16665672

  6. Affective responses to dance.

    PubMed

    Christensen, Julia F; Pollick, Frank E; Lambrechts, Anna; Gomila, Antoni

    2016-07-01

    The objective of the present work was the characterization of mechanisms by which affective experiences are elicited in observers when watching dance movements. A total of 203 dance stimuli from a normed stimuli library were used in a series of independent experiments. The following measures were obtained: (i) subjective measures of 97 dance-naïve participants' affective responses (Likert scale ratings, interviews); and (ii) objective measures of the physical parameters of the stimuli (motion energy, luminance), and of the movements represented in the stimuli (roundedness, impressiveness). Results showed that (i) participants' ratings of felt and perceived affect differed, (ii) felt and perceived valence but not arousal ratings correlated with physical parameters of the stimuli (motion energy and luminance), (iii) roundedness in posture shape was related to the experience of more positive emotion than edgy shapes (1 of 3 assessed rounded shapes showed a clear effect on positiveness ratings while a second reached trend level significance), (iv) more impressive movements resulted in more positive affective responses, (v) dance triggered affective experiences through the imagery and autobiographical memories it elicited in some people, and (vi) the physical parameters of the video stimuli correlated only weakly and negatively with the aesthetics ratings of beauty, liking and interest. The novelty of the present approach was twofold; (i) the assessment of multiple affect-inducing mechanisms, and (ii) the use of one single normed stimulus set. The results from this approach lend support to both previous and present findings. Results are discussed with regards to current literature in the field of empirical aesthetics and affective neuroscience.

  7. Affective responses to dance.

    PubMed

    Christensen, Julia F; Pollick, Frank E; Lambrechts, Anna; Gomila, Antoni

    2016-07-01

    The objective of the present work was the characterization of mechanisms by which affective experiences are elicited in observers when watching dance movements. A total of 203 dance stimuli from a normed stimuli library were used in a series of independent experiments. The following measures were obtained: (i) subjective measures of 97 dance-naïve participants' affective responses (Likert scale ratings, interviews); and (ii) objective measures of the physical parameters of the stimuli (motion energy, luminance), and of the movements represented in the stimuli (roundedness, impressiveness). Results showed that (i) participants' ratings of felt and perceived affect differed, (ii) felt and perceived valence but not arousal ratings correlated with physical parameters of the stimuli (motion energy and luminance), (iii) roundedness in posture shape was related to the experience of more positive emotion than edgy shapes (1 of 3 assessed rounded shapes showed a clear effect on positiveness ratings while a second reached trend level significance), (iv) more impressive movements resulted in more positive affective responses, (v) dance triggered affective experiences through the imagery and autobiographical memories it elicited in some people, and (vi) the physical parameters of the video stimuli correlated only weakly and negatively with the aesthetics ratings of beauty, liking and interest. The novelty of the present approach was twofold; (i) the assessment of multiple affect-inducing mechanisms, and (ii) the use of one single normed stimulus set. The results from this approach lend support to both previous and present findings. Results are discussed with regards to current literature in the field of empirical aesthetics and affective neuroscience. PMID:27235953

  8. Functional clustering for Italian climate zones identification

    NASA Astrophysics Data System (ADS)

    Di Giuseppe, E.; Jona Lasinio, G.; Esposito, S.; Pasqui, M.

    2013-10-01

    This work presents a functional clustering procedure applied to meteorological time series. Our proposal combines time series interpolation with smoothing penalized B-spline and the partitioning around medoids clustering algorithm. Our final goal is to obtain homogeneous climate zones of Italy. We compare this approach to standard methods based on a combination of principal component analysis and Cluster Analysis (CA) and we discuss it in relation to other functional clustering approaches based on Fourier analysis and CA. We show that a functional approach is simpler than the standard methods from a methodological and interpretability point of view. Indeed, it becomes natural to find a clear connection between mathematical results and physical variability mechanisms. We discuss how the choice of the basis expansion (splines, Fourier) affects the analysis and propose some comments on their use. The basis for classification is formed by monthly values of temperature and precipitation recorded during the period 1971-2000 over 95 and 94 Italian monitoring stations, respectively. An assessment based on climatic patterns is presented to prove the consistency of the clustering and a comparison of results obtained with different methods is used to judge the functional data approach.

  9. Cell migration in the postnatal subventricular zone.

    PubMed

    Menezes, J R L; Marins, M; Alves, J A J; Froes, M M; Hedin-Pereira, C

    2002-12-01

    New neurons are constantly added to the olfactory bulb of rodents from birth to adulthood. This accretion is not only dependent on sustained neurogenesis, but also on the migration of neuroblasts and immature neurons from the cortical and striatal subventricular zone (SVZ) to the olfactory bulb. Migration along this long tangential pathway, known as the rostral migratory stream (RMS), is in many ways opposite to the classical radial migration of immature neurons: it is faster, spans a longer distance, does not require radial glial guidance, and is not limited to postmitotic neurons. In recent years many molecules have been found to be expressed specifically in this pathway and to directly affect this migration. Soluble factors with inhibitory, attractive and inductive roles in migration have been described, as well as molecules mediating cell-to-cell and cell-substrate interactions. However, it is still unclear how the various molecules and cells interact to account for the special migratory behavior in the RMS. Here we will propose some candidate mechanisms for roles in initiating and stopping SVZ/RMS migration.

  10. Pan-European Chikungunya surveillance: designing risk stratified surveillance zones

    PubMed Central

    Tilston, Natasha; Skelly, Chris; Weinstein, Phil

    2009-01-01

    The first documented transmission of Chikungunya within Europe took place in Italy during the summer of 2007. Chikungunya, a viral infection affecting millions of people across Africa and Asia, can be debilitating and no prophylactic treatment exists. Although imported cases are reported frequently across Europe, 2007 was the first confirmed European outbreak and available evidence suggests that Aedes albopictus was the vector responsible and the index case was a visitor from India. This paper proposed pan-European surveillance zones for Chikungunya, based on the climatic conditions necessary for vector activity and viral transmission. Pan-European surveillance provides the best hope for an early-warning of outbreaks, because national boundaries do not play a role in defining the risk of this new vector borne disease threat. A review of climates, where Chikungunya has been active, was used to inform the delineation of three pan-European surveillance zones. These vary in size each month across the June-September period of greatest risk. The zones stretch across southern Europe from Portugal to Turkey. Although the focus of this study was to define the geography of potential surveillance zones based on the climatic limits on the vector and virus, a preliminary examination of inward bound airline passengers was also undertaken. This indicated that France and Italy are likely to be at greater risk due to the number of visitors they receive from Chikungunya active regions, principally viraemic visitors from India. Therefore this study represents a first attempt at creating risk stratified surveillance zones, which we believe could be usefully refined with the use of higher resolution climate data and more complete air travel data. PMID:19878588

  11. A Lagrangian stochastic model of surf zone drifter dispersion

    NASA Astrophysics Data System (ADS)

    Spydell, Matthew S.; Feddersen, Falk

    2012-03-01

    Drifter-derived cross-shore and alongshore surf zone diffusivities were previously estimated on an alongshore uniform beach over 1000 s for five Huntington Beach, California, 2006 (HB06) experiment release days. The cross-shore diffusivity Kx had a nonmonotonic time dependence, potentially due to the shoreline or to weaker diffusivity seaward of the surf zone. The alongshore diffusivities Ky were qualitatively consistent with shear dispersion but differed from the classic Taylor laminar theory. Here, modeled and analytic diffusivities for the five release days are derived from a Lagrangian stochastic model (LSM) that uses the drifter-derived bulk (cross-shore averaged) velocity variance and cross-shore-dependent mean alongshore current. The LSM modeled and analytic cross-shore diffusivities are nonmonotonic due to the shoreline and strongly suggest that the observed cross-shore diffusivity is shoreline affected. The LSM typically reproduce well the observed Kx with Lagrangian time scale between 75 and 200 s, consistent with surf zone eddy time scales. HB06 drifter trajectories were too short to observe the analytic long-time Kx limit, and weaker diffusivity seaward of the surf zone may be important at longer times (>1000 s). On all release days, the LSM model and analytic alongshore diffusivity reproduce well the observed Ky with alongshore Lagrangian time scales between 95 and 155 s. The isolated shear-induced diffusivity is very well represented by an analytic theory which incorporates a nonzero Lagrangian time scale. Many of the stochastic model parameters can be specified a priori with reasonable assumptions to predict surf zone dispersion of an initial value problem pollution spill.

  12. A Geophysical Study of the Carcavai Fault Zone, Portugal

    NASA Astrophysics Data System (ADS)

    Carvalho, J.; Ramalho, E.; Dias, R.; Pinto, C.; Ressurreição, R.

    2012-01-01

    The Algarve province is located a few hundred kilometres north of the crossing of the E-W Eurasia-Africa plate boundary in an area of diffuse seismicity and broad deformation. It is characterised by a moderate seismicity, with some important historical and instrumental earthquakes causing loss of lives and significant material damages. The area is affected not only by plate boundary earthquakes but also by moderate to large events generated by local sources. The assessment of onshore local sources is, therefore, of vital importance for an evaluation of the regional seismic hazard. This paper discusses the application of geophysical data to the study of the Carcavai fault zone, an outcropping structure more than 20 km long which is seen to deform sediments of the Plio-Quaternary age. The location of some sectors of the fault zone, as well as the vertical offsets of the structure, are still to be confirmed. In order to estimate these and to study the geometry of the fault zone at depth, geophysical data were acquired together with new geological data. Where the location of the fault was less certain, EM and seismic reflection profiles with coarse spatial sampling were carried out. After the detailed location of the fault zone, seismic reflection profiles with a more dense spatial resolution were acquired. The integrated interpretation of the geological and geophysical data confirmed the presence of a large fault zone. The total fault length is still unknown as its extension offshore is still being studied. Together with estimated values of the throw obtained, this data set has improved understanding the seismic hazard in the area by providing more refined estimates of co-seismic rupture, maximum expected earthquake and return periods.

  13. Zipper and freeway shear zone junctions

    NASA Astrophysics Data System (ADS)

    Passchier, Cees; Platt, John

    2016-04-01

    Ductile shear zones are usually presented as isolated planar high-strain domains in a less deformed wall rock, characterised by shear sense indicators such as characteristic deflected foliation traces. Many shear zones, however, form branched systems and if movement on such branches is contemporaneous, the resulting geometry can be complicated and lead to unusual fabric geometries in the wall rock. For Y-shaped shear zone junctions with three simultaneously operating branches, and with slip directions at a high angle to the branch line, eight basic types of shear zone triple junctions are possible, divided into three groups. The simplest type, called freeway junctions, have similar shear sense on all three branches. If shear sense is different on the three branches, this can lead to space problems. Some of these junctions have shear zone branches that join to form a single branch, named zipper junctions, or a single shear zone which splits to form two, known as wedge junctions. Closing zipper junctions are most unusual, since they form a non-active high-strain zone with opposite deflection of foliations. Shear zipper and shear wedge junctions have two shear zones with similar shear sense, and one with the opposite sense. All categories of shear zone junctions show characteristic flow patterns in the shear zone and its wall rock. Shear zone junctions with slip directions normal to the branch line can easily be studied, since ideal sections of shear sense indicators lie in the plane normal to the shear zone branches and the branch line. Expanding the model to allow slip oblique and parallel to the branch line in a full 3D setting gives rise to a large number of geometries in three main groups. Slip directions can be parallel on all branches but oblique to the branch line: two slip directions can be parallel and a third oblique, or all three branches can have slip in different directions. Such more complex shear zone junctions cannot be studied to advantage in a

  14. Gestational protein restriction affects trophoblast differentiation.

    PubMed

    Gao, Haijun; Yallampalli, Uma; Yallampalli, Chandra

    2013-01-01

    Whether and how gestational protein restriction (PR) affects placental development and function remain unknown. To test the hypothesis that PR can affect trophoblast differentiation in mid-and late pregnancy, rats were fed a 20% or an isocaloric 6% protein diet from Day 1 to 14 or 18 of pregnancy and effects of PR on trophoblast differentiation were determined by changes in expressions of marker gene(s) for trophoblast lineages. At Day 18 of pregnancy, PR increased expressions of Esrrb, Id1 andId2 (trophoblast stem cell markers), decreased expressions of Ascl2 (spongiotrophblast cell marker) and Prl2c1 (trophoblast giant cell marker), but did not alter expressions of Gjb3 and Pcdh12(glycogen cell markers) in the junctional zone (JZ). In the labyrinth zone (LZ), PR did not change expressions of Prl2b1 (trophoblast giant cell marker), Gcm1 and Syna (syncytiotrophoblast cell markers), but decrease expression of Ctsq (sinusoidal trophoblast giant cell marker). These results indicate that PR impairs the differentiation of trophoblast stem cell into spongiotrophoblast and trophoblast giant cells in JZ, and formation of sinusoidal trophoblast giant cells in LZ.

  15. Crustal growth in subduction zones

    NASA Astrophysics Data System (ADS)

    Vogt, Katharina; Castro, Antonio; Gerya, Taras

    2015-04-01

    There is a broad interest in understanding the physical principles leading to arc magmatisim at active continental margins and different mechanisms have been proposed to account for the composition and evolution of the continental crust. It is widely accepted that water released from the subducting plate lowers the melting temperature of the overlying mantle allowing for "flux melting" of the hydrated mantle. However, relamination of subducted crustal material to the base of the continental crust has been recently suggested to account for the growth and composition of the continental crust. We use petrological-thermo-mechanical models of active subduction zones to demonstrate that subduction of crustal material to sublithospheric depth may result in the formation of a tectonic rock mélange composed of basalt, sediment and hydrated /serpentinized mantle. This rock mélange may evolve into a partially molten diapir at asthenospheric depth and rise through the mantle because of its intrinsic buoyancy prior to emplacement at crustal levels (relamination). This process can be episodic and long-lived, forming successive diapirs that represent multiple magma pulses. Recent laboratory experiments of Castro et al. (2013) have demonstrated that reactions between these crustal components (i.e. basalt and sediment) produce andesitic melt typical for rocks of the continental crust. However, melt derived from a composite diapir will inherit the geochemical characteristics of its source and show distinct temporal variations of radiogenic isotopes based on the proportions of basalt and sediment in the source (Vogt et al., 2013). Hence, partial melting of a composite diapir is expected to produce melt with a constant major element composition, but substantial changes in terms of radiogenic isotopes. However, crustal growth at active continental margins may also involve accretionary processes by which new material is added to the continental crust. Oceanic plateaus and other

  16. Saltwater upconing zone of influence

    NASA Astrophysics Data System (ADS)

    Jakovovic, Danica; Werner, Adrian D.; de Louw, Perry G. B.; Post, Vincent E. A.; Morgan, Leanne K.

    2016-08-01

    In this study, we define and characterize the saltwater upconing zone of influence (SUZI). The SUZI is the region around a pumping well within which significant rise in the saltwater-freshwater interface occurs. While the zone of influence of a pumping well can be clearly defined in terms of hydraulics (e.g., drawdown), the SUZI has not been recognised and characterised, despite its importance for groundwater decision-making in coastal regions. We explore the SUZI under various conditions and compare common methods of investigation using both axisymmetric (1D and 2D vertical cross-section) and 3D simulations of saltwater upconing at the field scale, based on a combination of numerical and analytical approaches. The SUZI was found to be dependent on the relative magnitudes of pumping, regional flow, distance of the well from the coast, and position of the well above the interface, as expected. The three-dimensional coastal setting simulations revealed an asymmetric shape of the lateral extent of the SUZI, which is largest in the direction parallel to the coast. This occurs because the ocean and the inland extent of the seawater wedge limit the propagation of the SUZI perpendicular to the coast. Predictions of the SUZI using the Ghyben-Herzberg approximation, including cases where sloping interfaces occur (i.e., in contrast to the artificiality of horizontal interfaces used in axisymmetric approaches), provide reasonable first approximations of the SUZI. Numerical modelling of dispersive upconing in the 3D inclined interface case is influenced by practical limits to the model domain size and grid resolution. For example, the no-flow boundary condition at 1500 m from the pumping well elongates the SUZI in the direction parallel to the coast. This study extends previous concepts of well interference, which have previously been based on hydraulics only, by introducing the SUZI and characterising its extent, with consideration given to differences in commonly adopted

  17. Vadose zone monitoring for hazardous waste sites

    SciTech Connect

    Everett, L.G.

    1984-01-01

    This book is a review and evaluation of vadose (unsaturated) zone monitoring. It describes the applicability of selected monitoring methods to hazardous waste disposal sites. Topics covered include: geohydrologic framework of the vadose zone; premonitoring of storage at disposal sites; premonitoring of water movement at disposal sites; active and abandoned site monitoring methods; waste source pollutant characterization; geohydrologic settings for waste disposals and conceptual vadose zone monitoring descriptions.

  18. Automated zone correction in bitmapped document images

    NASA Astrophysics Data System (ADS)

    Hauser, Susan E.; Le, Daniel X.; Thoma, George R.

    1999-12-01

    The optical character recognition system (OCR) selected by the National Library of Medicine (NLM) as part of its system for automating the production of MEDLINER records frequently segments the scanned page images into zones which are inappropriate for NLM's application. Software has been created in-house to correct the zones using character coordinate and character attribute information provided as part of the OCR output data. The software correctly delineates over 97% of the zones of interest tested to date.

  19. Seismic Investigations of the Zagros-Bitlis Thrust Zone

    NASA Astrophysics Data System (ADS)

    Gritto, R.; Sibol, M.; Caron, P.; Quigley, K.; Ghalib, H.; Chen, Y.

    2009-05-01

    We present results of crustal studies obtained with seismic data from the Northern Iraq Seismic Network (NISN). NISN has operated 10 broadband stations in north-eastern Iraq since late 2005. At present, over 800 GB of seismic waveform data have been analyzed. The aim of the present study is to derive models of the local and regional crustal structure of north and north-eastern Iraq, including the northern extension of the Zagros collision zone. This goal is, in part, achieved by estimating local and regional seismic velocity models using receiver function- and surface wave dispersion analyses and to use these velocity models to obtain accurate hypocenter locations and event focal mechanisms. Our analysis of hypocenter locations produces a clear picture of the seismicity associated with the tectonics of the region. The largest seismicity rate is confined to the active northern section of the Zagros thrust zone, while it decreases towards the southern end, before the intensity increases in the Bandar Abbas region again. Additionally, the rift zones in the Read Sea and the Gulf of Aden are clearly demarked by high seismicity rates. Our analysis of waveform data indicates clear propagation paths from the west or south-west across the Arabian shield as well as from the north and east into NISN. Phases including Pn, Pg, Sn, Lg, as well as LR are clearly observed on these seismograms. In contrast, blockage or attenuation of Pg and Sg-wave energy is observed for propagation paths across the Zagros-Bitlis zone from the south, while Pn and Sn phases are not affected. These findings are in support of earlier tectonic models that suggested the existence of multiple parallel listric faults splitting off the main Zagros fault zone in east-west direction. These faults appear to attenuate the crustal phases while the refracted phases, propagating across the mantle lid, remain unaffected. We will present surface wave analysis in support of these findings, indicating multi

  20. The habitable zone and extreme planetary orbits.

    PubMed

    Kane, Stephen R; Gelino, Dawn M

    2012-10-01

    The habitable zone for a given star describes the range of circumstellar distances from the star within which a planet could have liquid water on its surface, which depends upon the stellar properties. Here we describe the development of the habitable zone concept, its application to our own solar system, and its subsequent application to exoplanetary systems. We further apply this to planets in extreme eccentric orbits and show how they may still retain life-bearing properties depending upon the percentage of the total orbit which is spent within the habitable zone. Key Words: Extrasolar planets-Habitable zone-Astrobiology.

  1. Personal audio with a planar bright zone.

    PubMed

    Coleman, Philip; Jackson, Philip J B; Olik, Marek; Pedersen, Jan Abildgaard

    2014-10-01

    Reproduction of multiple sound zones, in which personal audio programs may be consumed without the need for headphones, is an active topic in acoustical signal processing. Many approaches to sound zone reproduction do not consider control of the bright zone phase, which may lead to self-cancellation problems if the loudspeakers surround the zones. Conversely, control of the phase in a least-squares sense comes at a cost of decreased level difference between the zones and frequency range of cancellation. Single-zone approaches have considered plane wave reproduction by focusing the sound energy in to a point in the wavenumber domain. In this article, a planar bright zone is reproduced via planarity control, which constrains the bright zone energy to impinge from a narrow range of angles via projection in to a spatial domain. Simulation results using a circular array surrounding two zones show the method to produce superior contrast to the least-squares approach, and superior planarity to the contrast maximization approach. Practical performance measurements obtained in an acoustically treated room verify the conclusions drawn under free-field conditions. PMID:25324075

  2. The habitable zone and extreme planetary orbits.

    PubMed

    Kane, Stephen R; Gelino, Dawn M

    2012-10-01

    The habitable zone for a given star describes the range of circumstellar distances from the star within which a planet could have liquid water on its surface, which depends upon the stellar properties. Here we describe the development of the habitable zone concept, its application to our own solar system, and its subsequent application to exoplanetary systems. We further apply this to planets in extreme eccentric orbits and show how they may still retain life-bearing properties depending upon the percentage of the total orbit which is spent within the habitable zone. Key Words: Extrasolar planets-Habitable zone-Astrobiology. PMID:23035897

  3. Environmental conditions of boreal springs explained by capture zone characteristics

    NASA Astrophysics Data System (ADS)

    Rossi, Pekka M.; Marttila, Hannu; Jyväsjärvi, Jussi; Ala-aho, Pertti; Isokangas, Elina; Muotka, Timo; Kløve, Bjørn

    2015-12-01

    Springs are unique ecosystems, but in many cases they are severely threatened and there is an urgent need for better spring management and conservation. To this end, we studied water quality and quantity in springs in Oulanka National Park, north-east Finland. Multivariate statistical methods were employed to relate spring water quality and quantity to hydrogeology and land use of the spring capture zone. This revealed that most springs studied were affected by locally atypical dolostone-limestone bedrock, resulting in high calcium, pH, and alkalinity values. Using Ward's hierarchical clustering, the springs were grouped into four clusters based on their water chemistry. One cluster consisted of springs affected by past small-scale agriculture, whereas other clusters were affected by the variable bedrock, e.g., springs only 1 km from the dolostone-limestone bedrock area were beyond its calcium-rich impact zone. According to a random forest model, the best predictors of spring water chemistry were spring altitude and the stable hydrogen isotope ratio of the water (δ2H). Thus stable water isotopes could be widely applicable for boreal spring management. They may also provide a rough estimate of groundwater flow route (i.e., whether it is mainly local or regional), which largely determines the chemical characteristics of spring water. Our approach could be applied in other boreal regions and at larger spatial scales for improved classification of springs and for better targeted spring management.

  4. Elements affecting runway traction

    NASA Technical Reports Server (NTRS)

    Horne, W. B.

    1974-01-01

    The five basic elements affecting runway traction for jet transport aircraft operation are identified and described in terms of pilot, aircraft system, atmospheric, tire, and pavement performance factors or parameters. Where possible, research results are summarized, and means for restoring or improving runway traction for these different conditions are discussed.

  5. What Variables Affect Solubility?

    ERIC Educational Resources Information Center

    Baker, William P.; Leyva, Kathryn

    2003-01-01

    Helps middle school students understand the concept of solubility through hands-on experience with a variety of liquids and solids. As they explore factors that affect solubility and saturation, students gain content mastery and an understanding of the inquiry process. Also enables teachers to authentically assess student performance on several…

  6. How Body Affects Brain.

    PubMed

    Suzuki, Wendy A

    2016-08-01

    Studies show that physical exercise can affect a range of brain and cognitive functions. However, little is known about the peripheral signals that initiate these central changes. Moon et al. (2016) provide exciting new evidence that a novel myokine, cathepsin B (CTSB), released with exercise is associated with improved memory. PMID:27508865

  7. Food Affects Human Behavior.

    ERIC Educational Resources Information Center

    Kolata, Gina

    1982-01-01

    A conference on whether food and nutrients affect human behavior was held on November 9, 1982 at the Massachusetts Institute of Technology. Various research studies on this topic are reviewed, including the effects of food on brain biochemistry (particularly sleep) and effects of tryptophane as a pain reducer. (JN)

  8. Factors affecting soil cohesion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil erodibility is a measure of a soil’s resistance against erosive forces and is affected by both intrinsic (or inherent) soil property and the extrinsic condition at the time erodibility measurement is made. Since soil erodibility is usually calculated from results obtained from erosion experimen...

  9. Affective antecedents of revenge.

    PubMed

    O'Connor, Kieran; Adams, Gabrielle S

    2013-02-01

    We propose that revenge responses are often influenced more by affective reactions than by deliberate decision making as McCullough et al. suggest. We review social psychological evidence suggesting that justice judgments and reactions may be determined more by emotions than by cognitions.

  10. 76 FR 41065 - Safety Zones; Annual Events Requiring Safety Zones in the Captain of the Port Lake Michigan Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-13

    ... Register (76 FR 30072). We received no comments on the proposed rule. No public meeting was requested, and... the Port Lake Michigan zone in the Federal Register (76 FR 12374). The Coast Guard received 0 public... Michigan zone in the Federal Register (76 FR 12374). The Coast Guard received 0 public...

  11. Burdur-Fethiye Shear Zone (Eastern Mediterranean, SW Turkey)

    NASA Astrophysics Data System (ADS)

    Elitez, İrem; Yaltırak, Cenk

    2014-05-01

    Burdur-Fethiye Shear Zone (BFSZ), which was named as Burdur-Fethiye Fault Zone (BFFZ) in the previous studies, is located in the southwestern Anatolia between the eastern Aegean extensional province, the Hellenic Arc and the Isparta Angle. This tectonic line is characterized by Middle Miocene-Quaternary NE-SW-trending faults and basins and its length is about 310 km from north to south while its width ranges from about 15 km in the west of Afyon-Çay to about 90 km in between Patara and Dalaman-İztuzu. The Burdur-Fethiye Shear Zone (BFSZ) has been affected by three-phase tectonic evolution since Miocene. The uplift of the region began with a compressional regime in the Early Miocene and the alluvial fan sediments settled in the subsidence area between the mountains formed as a result of this uplift. During Middle-Late Miocene, the compression of the region inverted to a left-lateral oblique shear associated with the Isparta Angle and the fluvial sedimentation started in the inner part of the basins. In Late Miocene, the fluvial sedimentation gave way to lacustrine sedimentation. These lacustrine environments disappeared during Messinian salinity crisis. In the Pliocene, the erosion regime dominated the region and the uplifted Miocene-aged series started to erode. The red fluvial and alluvial fan deposits sedimented in the valleys and in front of the faults during this period. At the same period, the fault system inverted to a still-continuing left-lateral extensional shear system associated with the Hellenic Arc. The mechanism of the Burdur-Fethiye Shear Zone can be explained by the relative movement of the blocks formed by several parallel faults. The width of the BFSZ is approximately 50 km. In consideration of the counterclockwise rotation of the structures along this zone and the effects of shear tectonism, it is seen that this is a wide fault zone being controlled by normal faults in a wide region instead of a narrow region like North Anatolian and East

  12. [Air negative charge ion concentration and its relationships with meteorological factors in different ecological functional zones of Hefei City].

    PubMed

    Wei, Chaoling; Wang, Jingtao; Jiang, Yuelin; Zhang, Qingguo

    2006-11-01

    Air negative charge ion concentration (ANCIC) has a close relationship with air quality. The observations on the ANCIC, sunlight intensity, air temperature, and air relative humidity in different ecological functional zones of Hefei City from 2003 to 2004 showed that the diurnal change pattern of ANCIC was of single peak in sightseeing and habitation zones, dual peak in industrial zone, and complicated in commercial zone. Different ecological functional zones had different appearance time of their daily ANCIC extremum. The diurnal fluctuation of ANCIC was in the order of commercial zone > industrial zone > habitation zone and sightseeing zone. The annual change pattern of ANCIC in these zones was similar, being the highest in summer and lowest in winter, and the mean annual ANCIC was 819, 340, 149 and 126 ions x cm(-3), respectively. The most important meteorological factor affecting the ANCIC in Hefei City was air relative humidity, followed by sunlight intensity and air temperature. There was an exponential relationship between ANCIC and air relative humidity.

  13. Subduction zone guided waves: 3D modelling and attenuation effects

    NASA Astrophysics Data System (ADS)

    Garth, T.; Rietbrock, A.

    2013-12-01

    Waveform modelling is an important tool for understanding complex seismic structures such as subduction zone waveguides. These structures are often simplified to 2D structures for modelling purposes to reduce computational costs. In the case of subduction zone waveguide affects, 2D models have shown that dispersed arrivals are caused by a low velocity waveguide, inferred to be subducted oceanic crust and/or hydrated outer rise normal faults. However, due to the 2D modelling limitations the inferred seismic properties such as velocity contrast and waveguide thickness are still debated. Here we test these limitations with full 3D waveform modelling. For waveguide effects to be observable the waveform must be accurately modelled to relatively high frequencies (> 2 Hz). This requires a small grid spacing due to the high seismic velocities present in subduction zones. A large area must be modelled as well due to the long propagation distances (400 - 600 km) of waves interacting with subduction zone waveguides. The combination of the large model area and small grid spacing required means that these simulations require a large amount of computational resources, only available at high performance computational centres like the UK National super computer HECTOR (used in this study). To minimize the cost of modelling for such a large area, the width of the model area perpendicular to the subduction trench (the y-direction) is made as small as possible. This reduces the overall volume of the 3D model domain. Therefore the wave field is simulated in a model ';corridor' of the subduction zone velocity structure. This introduces new potential sources of error particularly from grazing wave side reflections in the y-direction. Various dampening methods are explored to reduce these grazing side reflections, including perfectly matched layers (PML) and more traditional exponential dampening layers. Defining a corridor model allows waveguide affects to be modelled up to at least 2

  14. Mid-crustal shear zone development under retrograde conditions: pressure-temperature-fluid constraints from the Kuckaus Mylonite Zone, Namibia

    NASA Astrophysics Data System (ADS)

    Diener, Johann F. A.; Fagereng, Åke; Thomas, Sukey A. J.

    2016-09-01

    The Kuckaus Mylonite Zone (KMZ) forms part of the larger Marshall Rocks-Pofadder shear zone system, a 550 km-long, crustal-scale strike-slip shear zone system that is localized in high-grade granitoid gneisses and migmatites of the Namaqua Metamorphic Complex. Shearing along the KMZ occurred ca. 40 Ma after peak granulite-facies metamorphism during a discrete tectonic event and affected the granulites that had remained at depth since peak metamorphism. Isolated lenses of metamafic rocks within the shear zone allow the P-T-fluid conditions under which shearing occurred to be quantified. These lenses consist of an unsheared core that preserves relict granulite-facies textures and is mantled by a schistose collar and mylonitic envelope that formed during shearing. All three metamafic textural varieties contain the same amphibolite-facies mineral assemblage, from which calculated pseudosections constrain the P-T conditions of deformation at 2.7-4.2 kbar and 450-480 °C, indicating that deformation occurred at mid-crustal depths through predominantly viscous flow. Calculated T-MH2O diagrams show that the mineral assemblages were fluid saturated and that lithologies within the KMZ must have been rehydrated from an external source and retrogressed during shearing. Given that the KMZ is localized in strongly dehydrated granulites, the fluid must have been derived from an external source, with fluid flow allowed by local dilation and increased permeability within the shear zone. The absence of pervasive hydrothermal fractures or precipitates indicates that, even though the KMZ was fluid bearing, the fluid/rock ratio and fluid pressure remained low. In addition, the fluid could not have contributed to shear zone initiation, as an existing zone of enhanced permeability is required for fluid infiltration. We propose that, following initiation, fluid infiltration caused a positive feedback that allowed weakening and continued strain localization. Therefore, the main

  15. The historical trend in float zone crystal diameters and power requirements for float zoned silicon crystals

    NASA Technical Reports Server (NTRS)

    Kramer, H. G.

    1981-01-01

    The power needed to zone silicon crystals by radio frequency heating was analyzed. The heat loss mechanisms are examined. Curves are presented for power as a function of crystal diameter for commercial silicon zoning.

  16. Dynamic Synchronization of Teacher-Students Affection in Affective Instruction

    ERIC Educational Resources Information Center

    Zhang, Wenhai; Lu, Jiamei

    2011-01-01

    Based on Bower's affective network theory, the article links the dynamic analysis of affective factors in affective instruction, and presents affective instruction strategic of dynamic synchronization between teacher and students to implement the best ideal mood that promotes students' cognition and affection together. In the process of teaching,…

  17. Origin of zoned fine-grained inclusions in the Allende meteorite

    SciTech Connect

    McGuire, A.V.; Hashimoto, Akihiko )

    1989-05-01

    Many fine-grained Ca-Al-rich inclusions in the Allende meteorite show a consistent pattern of mineralogic and textural zonation. The center, zone A, consists mostly of spinel, nepheline, Al-diopside and salite, with minor amounts of olivine, sodalite, grossular, anorthite, perovskite, and ilmenite. In most inclusions, these minerals occur as loosely packed, discrete anhedral to subhedral grains with only minor intergrowth between phases. The textural and mineralogical similarity of zone A, except for the rimmed spinel objects, to altered areas of coarse-grained melilite-rich CaIs suggests that a similar open system alteration affected the fine-grained inclusions and that zone A's contained melilite before being completely altered to anorthite, grossular, nepheline and sodalite. Under conditions of low temperatures (< 1,000 K) and/or at H/O ratios lower than the cosmic abundance, Ca is more volatile than Si due to the formation of gaseous Ca-hydroxides. The thermodynamic stability of minerals in zones A and B also indicates alteration at temperatures less than 1,000 K. The mode of occurrence of hedenbergite and andradite in zone B implies that they are condensates deposited on the edge of zone A. It is likely that the Ca migrating out of the center of the inclusions and the Si and Fe migrating inward from the surrounding nebular gas coprecipitated according to the thermodynamic stability of these minerals. Zone C, on the other hand most likely existed even before alteration, surrounding what is now zone A. However, the mineralogy of zone C appears to have changed by alteration: the zone C consisting of olivine, nepheline and ilmenite was probably a spinel-rich belt mantling the illusion.

  18. Nitrogen fluxes through unsaturated zones in five agricultural settings across the USA

    NASA Astrophysics Data System (ADS)

    Green, C. T.; Fisher, L. H.; Bekins, B. A.

    2006-12-01

    The main controls on nitrogen (N) fluxes between the root zone and the water table were determined for agricultural sites in California, Washington, Nebraska, Indiana, and Maryland in 2004 and 2005. Sites included irrigated and non-irrigated fields; soil textures ranging from clay to sand; crops including corn, soybeans, almonds, and pasture; and unsaturated zone thicknesses ranging from 0.5 to 20 m. Chemical analyses of water from lysimeters, shallow wells, and sediment cores indicate that advective transport of nitrate is the dominant process affecting the rate of N transport below the root zone. Vertical profiles of (1) N species, (2) stable N and O isotopes, and (3) oxygen gas in unsaturated zone air and shallow ground water, and correlations between N and other agricultural chemicals indicate that reactions do not greatly affect N concentrations between the root zone and the capillary fringe. Relatively stable concentrations at depths greater than a few meters allow calculation of nitrogen fluxes to the saturated zone. These fluxes are equivalent to 14 - 64% of the N application rates. At the same locations, median vertical fluxes of N in ground water are generally lower, ranging from 4 - 37% of N application rates. The lower nitrate fluxes in ground water reflect processes including lateral flow to tile drains and denitrification in the capillary fringe, as well as historical changes in N inputs.

  19. 78 FR 40961 - Safety Zones; Annual Events in the Captain of the Port Detroit Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-09

    ..., OH. The safety zone listed in 33 CFR 165.941(a)(22) will be enforced from 10:15 p.m. until 10:30 p.m... enforce various safety zones for annual marine events in the Captain of the Port Detroit zone from 9:30 p.m. on June 20, 2013 through 11:59 p.m. on August 31, 2013. Enforcement of these zones is...

  20. RADIATION ACCESS ZONE AND VENTILATION CONFINEMENT ZONE CRITERIA FOR THE MGR SURFACE FACILITIES

    SciTech Connect

    D. A. Padula

    2000-09-13

    The objectives of this technical report are to: (1) Establish the criteria for Radiation Access Zone (RAZ) designation. (2) Establish the criteria for the Ventilation Confinement Zone (VCZ) designation. The scope will be to formulate the RAZ and VCZ zoning designation for the Monitored Geologic Repository (MGR) surface facilities and to apply the zoning designations to the current Waste Handling Building (WHB), Waste Treatment Building (WTB), and Carrier Preparation Building (CPB) configurations.

  1. 77 FR 48856 - Safety Zones; Annual Fireworks Event in the Captain of the Port Detroit Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-15

    ... Detroit Zone AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce a safety zone for an annual fireworks event in the Captain of the Port Detroit zone... email LT Adrian Palomeque, Prevention, U.S. Coast Guard Sector Detroit, 110 Mount Elliot Ave.,...

  2. 76 FR 33154 - Safety Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-08

    ... Detroit Zone AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce various safety zones for annual fireworks events in the Captain of the Port Detroit... Fireworks Events in the Captain of the Port Detroit Zone, at the following time for the following...

  3. 77 FR 6007 - Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-07

    .... Regulated Navigation Areas are water areas within a defined boundary for which regulations for vessels.../2011 USCG-2011-0596 Grande Isle, LA Safety Zone (Part 165).... 7/2/2011 USCG-2011-0609 Buffalo, NY Safety Zone (Part 165).... 7/4/2011 USCG-2011-0609 Buffalo, NY Safety Zone (Part 165).... 7/24/2011...

  4. Nature, Humans, and the Coastal Zone.

    ERIC Educational Resources Information Center

    Walker, H. Jesse

    1990-01-01

    Considers the interface of humans and seacoasts over time. Explains how coastal zones are formed and human attempts to defend against sea level changes. Charts the percentage of major world cities that also are ports. Postulates how the greenhouse effect could influence sea level, examining potential human responses to changes in coastal zones.…

  5. Future float zone development in industry

    NASA Technical Reports Server (NTRS)

    Sandfort, R. M.

    1980-01-01

    The present industrial requirements for float zone silicon are summarized. Developments desired by the industry in the future are reported. The five most significant problems faced today by the float zone crystal growth method in industry are discussed. They are economic, large diameter, resistivity uniformity, control of carbon, and swirl defects.

  6. 78 FR 15883 - Standard Time Zone Boundaries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-13

    ... Office of the Secretary 49 CFR Part 71 RIN 2105-AE20 Standard Time Zone Boundaries AGENCY: Office of the... and amends the Department's standard time zone boundaries regulations to reflect changes that Congress made to the Uniform Time Act. The purpose of this update is to ensure that the Department's...

  7. Treating tar sands formations with karsted zones

    SciTech Connect

    Vinegar, Harold J.; Karanikas, John Michael

    2010-03-09

    Methods for treating a tar sands formation are described herein. The tar sands formation may have one or more karsted zones. Methods may include providing heat from one or more heaters to one or more karsted zones of the tar sands formation to mobilize fluids in the formation. At least some of the mobilized fluids may be produced from the formation.

  8. 33 CFR 165.30 - Security zones.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Security zones. 165.30 Section 165.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Security Zones §...

  9. 47 CFR 73.609 - Zones.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 4 2012-10-01 2012-10-01 false Zones. 73.609 Section 73.609 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Television Broadcast Stations § 73.609 Zones. (a) For the purpose of allotment and assignment, the United States...

  10. 46 CFR 76.27-5 - Zoning.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Electric Fire Detecting System, Details § 76.27-5 Zoning. (a) The fire detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) All spaces in a fire...

  11. 46 CFR 76.30-5 - Zoning.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Pneumatic Fire Detecting System, Details § 76.30-5 Zoning. (a) The fire detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) All spaces in a fire...

  12. 46 CFR 76.30-5 - Zoning.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Pneumatic Fire Detecting System, Details § 76.30-5 Zoning. (a) The fire detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) All spaces in a fire...

  13. 46 CFR 76.27-5 - Zoning.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Electric Fire Detecting System, Details § 76.27-5 Zoning. (a) The fire detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) All spaces in a fire...

  14. 46 CFR 76.27-5 - Zoning.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Electric Fire Detecting System, Details § 76.27-5 Zoning. (a) The fire detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) All spaces in a fire...

  15. 46 CFR 76.27-5 - Zoning.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Electric Fire Detecting System, Details § 76.27-5 Zoning. (a) The fire detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) All spaces in a fire...

  16. 46 CFR 76.30-5 - Zoning.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Pneumatic Fire Detecting System, Details § 76.30-5 Zoning. (a) The fire detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) All spaces in a fire...

  17. 46 CFR 76.30-5 - Zoning.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Pneumatic Fire Detecting System, Details § 76.30-5 Zoning. (a) The fire detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) All spaces in a fire...

  18. 46 CFR 76.30-5 - Zoning.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Pneumatic Fire Detecting System, Details § 76.30-5 Zoning. (a) The fire detecting system shall be divided into separate zones to restrict the area covered by any particular alarm signal. (b) All spaces in a fire...

  19. 40 CFR 227.28 - Release zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Release zone. 227.28 Section 227.28 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Definitions § 227.28 Release zone....

  20. 40 CFR 227.28 - Release zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Release zone. 227.28 Section 227.28 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Definitions § 227.28 Release zone....

  1. 40 CFR 227.28 - Release zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Release zone. 227.28 Section 227.28 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Definitions § 227.28 Release zone....

  2. 40 CFR 227.28 - Release zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Release zone. 227.28 Section 227.28 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Definitions § 227.28 Release zone....

  3. Laser furnace technology for zone refining

    NASA Technical Reports Server (NTRS)

    Griner, D. B.

    1984-01-01

    A carbon dioxide laser experiment facility is constructed to investigate the problems in using a laser beam to zone refine semiconductor and metal crystals. The hardware includes a computer to control scan mirrors and stepper motors to provide a variety of melt zone patterns. The equipment and its operating procedures are described.

  4. 33 CFR 165.30 - Security zones.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Security zones. 165.30 Section 165.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Security Zones §...

  5. 33 CFR 165.30 - Security zones.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Security zones. 165.30 Section 165.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Security Zones §...

  6. 33 CFR 165.30 - Security zones.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Security zones. 165.30 Section 165.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Security Zones §...

  7. Arabian peninsula: zone of ferment

    SciTech Connect

    Stookey, R.W.

    1984-01-01

    The Arabian Peninsula is an area which must be approached in terms of its own values and traditions. The different states, however, present difficulties for even the most well-informed policymaker because the region is not homogeneous. Some of the states are tenuous congeries of tribal and sectarian communities that do not necessarily share the aims of the ruling group. The authors of these six essays consider (1) the economic position of the states, (2) how oil exports affect the economies of the exporting states, (3) how traditional tribal and religious societies react to change, (4) whether their social values are conducive to modernization, and (5) what factors lead to the development of dissent, and how they affect the expression of dissent. Separate abstracts were prepared for two of the essays selected for the Energy Data Base (EDB) and Energy Abstracts for Policy Analysis (EAPA). 23 tables.

  8. Influence of the Hyporheic Zone on Supersaturated Gas Exposure to Incubating Chum Salmon

    SciTech Connect

    Arntzen, Evan V.; Geist, David R.; Murray, Katherine J.; Vavrinec, John; Dawley, Earl M.; Schwartz, Dennis E.

    2009-12-01

    Supersaturated total dissolved gas (TDG) is elevated seasonally in the lower Columbia River, with surface water concentrations approaching 120% saturation of TDG. Chum salmon (Oncorhynchus keta) embryos incubating in nearby spawning areas could be affected if depth-compensated TDG concentrations within the hyporheic zone exceed 103% TDG. The objective of this study was to determine if TDG of the hyporheic zone in two chum salmon spawning areas -- one in a side channel near Ives Island, Washington, and another on the mainstem Columbia River near Multnomah Falls, Oregon -- was affected by the elevated TDG of the surface water. Depth-compensated hyporheic TDG did not exceed 103% at the Multnomah Falls site. However, in the Ives Island area, chum salmon redds were exposed to TDG greater than 103% for more than 600 hours. In response to river depth fluctuations, TDG varied significantly in the Ives Island area, suggesting increased interaction between the hyporheic zone and surface water at that site. We conclude from this study that the interaction between surface water and the hyporheic zone affects the concentration of TDG within the hyporheic zone directly via physical mixing as well as indirectly by altering water chemistry and thus dissolved gas solubility. These interactions are important considerations when estimating TDG exposure within egg pocket environments, facilitating improved exposure estimates, and enabling managers to optimize recovery strategies.

  9. Frontiers in Critical Zone Science: Science Advances for the Next 10 Years

    NASA Astrophysics Data System (ADS)

    Silver, W. L.

    2014-12-01

    The Critical Zone Network is uniquely poised to help society devise innovative solutions to mounting environmental problems. By linking geologic, ecologic, hydrologic, and atmospheric sciences, research in the critical zone has the potential to transform our understanding of natural and managed ecosystems and their responses to environmental change. Emerging research questions include augmenting carbon sequestration by using the connectivity of key processes in the carbon cycle from bedrock to the atmosphere, determining the uses and limits of water as the conduit for materials and energy in the critical zone, and managing minerals as drivers of carbon storage and greenhouse gas dynamics. Future and continued collaborations with other large research networks with complementary expertise will not only strengthen the Critical Zone Network, but also expand the breadth and depth of understanding of the role of the critical zone in global-scale phenomena. Two examples of key networks include the US National Ecological Observatory Network (NEON) and the US and International Long Term Ecological Research Network (LTER). Networks such as these provide value added by broadening the range of climate, rock and soil type, vegetation characteristics, and human land use affecting the critical zone that should help us determine patterns and processes of critical zone function.

  10. Quantifying the spatiotemporal dynamics in a chorus frog (Pseudacris) hybrid zone over 30 years.

    PubMed

    Engebretsen, Kristin N; Barrow, Lisa N; Rittmeyer, Eric N; Brown, Jeremy M; Moriarty Lemmon, Emily

    2016-07-01

    Although theory suggests that hybrid zones can move or change structure over time, studies supported by direct empirical evidence for these changes are relatively limited. We present a spatiotemporal genetic study of a hybrid zone between Pseudacris nigrita and P. fouquettei across the Pearl River between Louisiana and Mississippi. This hybrid zone was initially characterized in 1980 as a narrow and steep "tension zone," in which hybrid populations were inferior to parentals and were maintained through a balance between selection and dispersal. We reanalyzed historical tissue samples and compared them to samples of recently collected individuals using microsatellites. Clinal analyses indicate that the cline has not shifted in roughly 30 years but has widened significantly. Anthropogenic and natural changes may have affected selective pressure or dispersal, and our results suggest that the zone may no longer best be described as a tension zone. To the best of our knowledge, this study provides the first evidence of significant widening of a hybrid cline but stasis of its center. Continued empirical study of dynamic hybrid zones will provide insight into the forces shaping their structure and the evolutionary potential they possess for the elimination or generation of species.

  11. Quantifying the spatiotemporal dynamics in a chorus frog (Pseudacris) hybrid zone over 30 years.

    PubMed

    Engebretsen, Kristin N; Barrow, Lisa N; Rittmeyer, Eric N; Brown, Jeremy M; Moriarty Lemmon, Emily

    2016-07-01

    Although theory suggests that hybrid zones can move or change structure over time, studies supported by direct empirical evidence for these changes are relatively limited. We present a spatiotemporal genetic study of a hybrid zone between Pseudacris nigrita and P. fouquettei across the Pearl River between Louisiana and Mississippi. This hybrid zone was initially characterized in 1980 as a narrow and steep "tension zone," in which hybrid populations were inferior to parentals and were maintained through a balance between selection and dispersal. We reanalyzed historical tissue samples and compared them to samples of recently collected individuals using microsatellites. Clinal analyses indicate that the cline has not shifted in roughly 30 years but has widened significantly. Anthropogenic and natural changes may have affected selective pressure or dispersal, and our results suggest that the zone may no longer best be described as a tension zone. To the best of our knowledge, this study provides the first evidence of significant widening of a hybrid cline but stasis of its center. Continued empirical study of dynamic hybrid zones will provide insight into the forces shaping their structure and the evolutionary potential they possess for the elimination or generation of species. PMID:27547330

  12. Trading Zones in Early Modern Europe.

    PubMed

    Long, Pamela O

    2015-12-01

    This essay adopts the concept of trading zones first developed for the history of science by Peter Galison and redefines it for the early modern period. The term "trading zones" is used to mean arenas in which substantive and reciprocal communication occurred between individuals who were artisanally trained and learned (university-trained) individuals. Such trading zones proliferated in the sixteenth century. They tended to arise in certain kinds of places and not in others, but their existence must be determined empirically. The author's work on trading zones differs from the ideas of Edgar Zilsel, who emphasized the influence of artisans on the scientific revolution. In contrast, in this essay, the mutual influence of artisans and the learned on each other is stressed, and translation is used as a modality that was important to communication within trading zones. PMID:27024940

  13. Managing speed at school and playground zones.

    PubMed

    Kattan, Lina; Tay, Richard; Acharjee, Shanti

    2011-09-01

    Since speeding is one of the major causes of frequent and severe traffic accidents around school and playground areas, many jurisdictions have reduced the speed limits in these areas to protect children who may be at risk. This paper investigated the speed compliance, mean speed and 85th percentile speed at selected school and playground zones in the City of Calgary in Alberta. Our results showed that the mean speed was lower and the rate of compliance was higher in the school zone compared to the playground zone, 2 lane roads relative to 4 lane roads, roads with fencing, traffic control devices and the presence of speed display device or children, and zones that were longer (> 200 m). Accordingly, this study provided recommendations to improve the effectiveness of school and playground zone speed limits. PMID:21658518

  14. Pollinators and Other Flying Insects inside and outside the Fukushima Evacuation Zone.

    PubMed

    Yoshioka, Akira; Mishima, Yoshio; Fukasawa, Keita

    2015-01-01

    Following the accident at the Fukushima Daiichi nuclear power plants in 2011, a large evacuation zone was imposed in an area where residents had historically managed forests and farmlands. Thus, the human activities that had maintained biodiversity and ecosystem services in the zone were discontinued. Such change can affect insects, a biodiversity component that is relatively tolerant to radiation exposure. In this study, we investigated flying insects, including pollinators, important ecosystem providers inside and outside the zone, using Malaise traps. The results showed that the number of individuals of Xylocopa appendiculata, the largest Apidae species in the region, was significantly lower inside the evacuation zone than outside it, whereas those of other insects were not lower significantly. Although we suggest that flying insects and their ecosystem services (i.e., benefits from them such as pollination) 3 years after the disaster were not critically impacted, it is important to monitor the long-term effects of the evacuation in the future.

  15. Nitrogen processing in the hyporheic zone and its response to stream-groundwater interactions

    NASA Astrophysics Data System (ADS)

    Grant, Stanley; Azizian, Morvarid; Boano, Fulvio

    2016-04-01

    Modeling and experimental studies have shown that stream-groundwater interactions reduce hyporheic exchange, but the implications of this observation for hyporheic zone function are not yet clear. In this study we develop and test a simple process-based model for nitrate cycling in the hyporheic zone of a gaining or losing stream. Our model reproduces field measurements of nitrate uptake velocity and predicts that stream-groundwater interactions: (1) reduce hyporheic exchange; (2) reduce the residence time of water in the hyporheic zone; (3) slow denitrification; and (4) can cause stream sediments to switch from a net sink to source of nitrate. Stream-groundwater interactions attenuate denitrification across at least two scales of hyporheic exchange (fluvial dunes and riffle-pool bedforms). These results suggest that changes in regional groundwater hydrology (e.g., brought on by climate change) can indirectly affect stream nitrogen budgets by altering the form and function of the hyporheic zone.

  16. Pollinators and Other Flying Insects inside and outside the Fukushima Evacuation Zone

    PubMed Central

    Yoshioka, Akira; Mishima, Yoshio; Fukasawa, Keita

    2015-01-01

    Following the accident at the Fukushima Daiichi nuclear power plants in 2011, a large evacuation zone was imposed in an area where residents had historically managed forests and farmlands. Thus, the human activities that had maintained biodiversity and ecosystem services in the zone were discontinued. Such change can affect insects, a biodiversity component that is relatively tolerant to radiation exposure. In this study, we investigated flying insects, including pollinators, important ecosystem providers inside and outside the zone, using Malaise traps. The results showed that the number of individuals of Xylocopa appendiculata, the largest Apidae species in the region, was significantly lower inside the evacuation zone than outside it, whereas those of other insects were not lower significantly. Although we suggest that flying insects and their ecosystem services (i.e., benefits from them such as pollination) 3 years after the disaster were not critically impacted, it is important to monitor the long-term effects of the evacuation in the future. PMID:26561045

  17. Pollinators and Other Flying Insects inside and outside the Fukushima Evacuation Zone.

    PubMed

    Yoshioka, Akira; Mishima, Yoshio; Fukasawa, Keita

    2015-01-01

    Following the accident at the Fukushima Daiichi nuclear power plants in 2011, a large evacuation zone was imposed in an area where residents had historically managed forests and farmlands. Thus, the human activities that had maintained biodiversity and ecosystem services in the zone were discontinued. Such change can affect insects, a biodiversity component that is relatively tolerant to radiation exposure. In this study, we investigated flying insects, including pollinators, important ecosystem providers inside and outside the zone, using Malaise traps. The results showed that the number of individuals of Xylocopa appendiculata, the largest Apidae species in the region, was significantly lower inside the evacuation zone than outside it, whereas those of other insects were not lower significantly. Although we suggest that flying insects and their ecosystem services (i.e., benefits from them such as pollination) 3 years after the disaster were not critically impacted, it is important to monitor the long-term effects of the evacuation in the future. PMID:26561045

  18. Capillary zone electrophoresis-mass spectrometry of peptides and proteins

    SciTech Connect

    Loo, J.A.; Udseth, H.R.; Smith, R.D.

    1989-05-01

    Capillary zone electrophoresis (CZE) is attracting extensive attention as a fast, high resolution analytical and micro-preparative separations technique for systems of biological interest. In zone electrophoresis, a column is filled with a single electrolyte having a specific conductivity. The mixture of substances to be separated is applied as a narrow band to the head of a buffer filled column in a band whose width is much less than the length of the column and at a concentration too low to affect the buffer conductivity. An electric field is then applied across the length of the column and the individual substances migrate and separate according to their net electrophoretic velocities. Zone electrophoresis carried out in small diameter (<100 ..mu..m) fused silica capillaries is a relatively new approach to the high resolution separation of aqueous samples. Very small volume samples (picoliter range) with separation efficiencies on the order of 10/sup 6/ theoretical plates for amino acids have been achieved. The method can be further enhanced by the dynamic combination of detection sensitivity and selectivity offered by mass spectrometry (MS). The on-line marriage of mass spectrometry to CZE is accomplished by an atmospheric pressure electrospray ionization source interface. Our research efforts have demonstrated that proteins with MW's greater than 100 kDa can be analyzed using a conventional quadrupole mass spectrometer with an upper m/z limit of only 1700. 6 refs.

  19. Tungsten Inert Gas and Friction Stir Welding Characteristics of 4-mm-Thick 2219-T87 Plates at Room Temperature and -196 °C

    NASA Astrophysics Data System (ADS)

    Lei, Xuefeng; Deng, Ying; Yin, Zhimin; Xu, Guofu

    2014-06-01

    2219-T87 aluminum alloy is widely used for fabricating liquid rocket propellant storage tank, due to its admirable cryogenic property. Welding is the dominant joining method in the manufacturing process of aerospace components. In this study, the tungsten inert gas welding and friction stir welding (FSW) characteristics of 4-mm-thick 2219-T87 alloy plate at room temperature (25 °C) and deep cryogenic temperature (-196 °C) were investigated by property measurements and microscopy methods. The studied 2219 base alloy exhibits a low strength plane anisotropy and excellent room temperature and cryogenic mechanical properties. The ultimate tensile strength values of TIG and FSW welding joints can reach 265 and 353 MPa at room temperature, and 342 and 438 MPa at -196 °C, respectively. The base metal consists of elongated deformed grains and many nano-scaled θ (Al2Cu) aging precipitates. Fusion zone and heat-affected zone (HAZ) of the TIG joint are characterized by coarsening dendritic grains and equiaxed recrystallized grains, respectively. The FSW-welded joint consists of the weld nugget zone, thermo-mechanically affected zone (TMAZ), and HAZ. In the weld nugget zone, a micro-scaled sub-grain structure is the main microstructure characteristic. The TMAZ and HAZ are both characterized by coarsened aging precipitates and elongated deformed grains. The excellent FSW welding properties are attributed to the preservation of the working structures and homogenous chemical compositions.

  20. Microstructure and Properties of TIG/FSW Welded Joints of a New Al-Zn-Mg-Sc-Zr Alloy

    NASA Astrophysics Data System (ADS)

    Lei, Xuefeng; Deng, Ying; Peng, Yongyi; Yin, Zhimin; Xu, Guofu

    2013-09-01

    A new Al-Zn-Mg-Sc-Zr alloy with low Sc content was welded by tungsten inert gas (TIG) and friction stir welding (FSW) techniques. The microstructure and properties of those two welded joints were investigated by property tests and microstructural observations. The results show that the new Al-Zn-Mg-Sc-Zr alloy has desirable welding property. The ultimate tensile strength and welding coefficient of the TIG joint reach 405 MPa and 76.7%, respectively, and in FSW joint those property values reach 490 MPa and 92.6%, respectively. The studied base metal has a deformed fibrous subgrains structure, many nano-scaled Al3(Sc,Zr) particles, and very fine aging precipitates. In the TIG joint, the fusion zone consists of coarsened dendritic grains and the heat-affected zone (HAZ) has fibrous micro-scaled subgrains. The FSW welded joint is characterized by a weld nugget zone, thermo-mechanically affected zone (TMAZ), and HAZ. Due to plastic deformation around the rotating pin and anti-recrystallized effectiveness of Al3(Sc,Zr) particles, the weld nugget zone has a very fine subgrain structure. The TMAZ experiences some dissolution of aging precipitates. Coarsening of aging precipitates was observed in the HAZ. The better mechanical properties of the FSW joint are derived from a fine subgrain structure and homogeneous chemical compositions.

  1. Using patterns of debris flow erosion and deposition in the Icelandic Westfjords to delineate hazard zones.

    NASA Astrophysics Data System (ADS)

    Conway, S. J.; Decaulne, A.; Balme, M. R.; Murray, J. B.; Towner, M. C.

    2009-04-01

    function of the slopes (calculated from digital elevation models) along the path of the flow. Using this relationship along potential flow paths identified with standard flow routing algorithms (e.g. [7]), we have highlighted several zones in the upper parts of the town that are at significant risk from debris flows. Most at risk are those areas of the town that have higher slope-angles and are without the protection of drainage ditches or small tree plantations, which would be reached by even a small flow. However in the worst case there are several areas below the ditches or trees that would be at risk if the flow was large, as the flow would reach a depth great enough to overcome these obstacles. The flows that we studied are composed of different source materials and are located in different geological settings, so we suggest that this method could be applied to any debris flow. Testing its applicability to other areas is an ideal avenue for future research. Acknowledgments: Support for this work was provided by NERC, the Geological Society, British Society for Geomorphology, the Dudley Stamp Memorial Fund and the Earth and Space Awards. Devrim Akca is gratefully acknowledged for software to analyse LiDAR data. References cited: [1] Arnalds, Þ. et al (2002) Hazard zoning for Ísafjörður and Hnífsdalur Technical report, Veðurstofa Íslands. [2] Decaulne, A. et al (2005) Geogr. Ann., 87A(4), 487-500. [3] Larsson, S. (1982) Geogr. Ann., 64A(3-4), 105-125. [4] Lorente, A. et al (2003) Nat. Haz. & Earth Sys. Sci., 3(6), 683-692. [5] Rapp, A. and Nyberg, R. (1981) Geogr. Ann., 63(3-4), 183-196. [6] Rickenmann, D. (1999) Nat. Haz., 19(1), 47-77. [7] Marcello, R. (2008) GeoInformatica, 13(2), 1-9

  2. Preliminary investigation of factors affecting the seismic potential of the Bartlett Springs fault zone, northern California

    NASA Astrophysics Data System (ADS)

    Lienkaemper, J. J.; Brown, J.

    2009-12-01

    The Bartlett Springs fault (BFS) extends 170 km from its south end, a large releasing bend in the Hunting Creek fault, to its north end, another large releasing bend in the Lake Mountain fault. The seismic potential of BFS is poorly known because of incomplete mapping, poorly constrained geologic slip rate and creep rates. Before our study only part of BFS was mapped as Holocene-active for a variety of reasons including the heavy rainfall and steep slopes causing extreme erosional conditions (many landslides), heavy vegetation and lack of detailed aerial photography. We acquired new 1:12,000-scale aerial photography of the entire BFS, from which we interpreted geomorphic features that indicate Holocene faulting extends along the entire BFS. The new mapping, formatted for use in geographic information systems, clarifies possible geometric constraints on fault segmentation. To better constrain the spatial variation of creep rate along BFS, we increased creep monitoring sites from two to four, presenting the latest results in our poster. The 4-yr average creep rate for our Lake Pillsbury site is 2.8 ± 0.4 mm/yr (1-SD), comparable to a creep rate estimated from a step in the velocity field (3.4 ± 0.8 mm/yr) using all USGS GPS array points across the central BSF. Lacking a geologic slip rate for BSF, we estimate an average velocity across the fault using a rigid block model of the GPS site velocities. This yields ~6.5 mm/yr, which is comparable to the 6 mm/yr long-term rate observed on the Northern Calaveras fault (NCF). Much NCF slip and probably additional slip from the Greenville fault transfers indirectly to the BSF via the Concord-Green Valley fault (CGVF). The NCF and CGVF have long-term creep rates ranging from 1.8-4.4 mm/yr, comparable to our estimates for BSF. For seismic hazard estimation, the segmentation of the BSF may depend on many factors, including the spatial variation in aseismic moment release, the size and 3D structure of the largest geometric discontinuities, the state of stress relative to the failure stress of each section and the timing and extent of previous ruptures. Microseismicity distribution is also relevant to seismic potential, because it tends to correlate with fault creep. The central third of the BSF has high microseismicity and with respect to with the plate boundary its strike ranges from transtensional to parallel, thus favoring stable sliding and unclamping. Our mapping indicates the largest BSF discontinuities are a 2.5-km left stepover at the Middle Fork of the Eel River and a 2.5-km right stepover at Wilson Valley. Some previous hazard models have assumed the BFS is likely to have a complete 170-km rupture of Mw~7.2, however, shorter rupture scenarios may be much more likely. For example, one more plausible rupture, for the ~70-km central section having high microseismicity, yields Mw~6.8, because its rupture would tend to terminate in the adjacent sections oriented favorably to locking. Many other plausible scenarios for segments of varying length can be posed, each needing to be weighted inversely to the likely difficulty of each rupture to occur.

  3. Superconducting accelerator cavity with a heat affected zone having a higher RRR

    DOEpatents

    Brawley, John; Phillips, H. Lawrence

    2000-01-01

    An improved method for welding accelerator cavities without the need for time consuming and expensive faying surface treatments comprising electron beam welding such cavities in a vacuum welding chamber within a vacuum envelope and using the following welding parameters: a beam voltage of between about 45 KV and 55 KV; a beam current between about 38 ma and 47 ma; a weld speed of about 15 cm/min; and a sharp focus and a rhombic raster of between about 9 KHz and 10 Khz. A welded cavity made according to the method of the present invention is also described.

  4. Hurricane Wilma's impact on overall soil elevation and zones within the soil profile in a mangrove forest

    USGS Publications Warehouse

    Whelan, K.R.T.; Smith, T. J.; Anderson, G.H.; Ouellette, M.L.

    2009-01-01

    Soil elevation affects tidal inundation period, inundation frequency, and overall hydroperiod, all of which are important ecological factors affecting species recruitment, composition, and survival in wetlands. Hurricanes can dramatically affect a site's soil elevation. We assessed the impact of Hurricane Wilma (2005) on soil elevation at a mangrove forest location along the Shark River in Everglades National Park, Florida, USA. Using multiple depth surface elevation tables (SETs) and marker horizons we measured soil accretion, erosion, and soil elevation. We partitioned the effect of Hurricane Wilma's storm deposit into four constituent soil zones: surface (accretion) zone, shallow zone (0–0.35 m), middle zone (0.35–4 m), and deep zone (4–6 m). We report expansion and contraction of each soil zone. Hurricane Wilma deposited 37.0 (± 3.0 SE) mm of material; however, the absolute soil elevation change was + 42.8 mm due to expansion in the shallow soil zone. One year post-hurricane, the soil profile had lost 10.0 mm in soil elevation, with 8.5 mm of the loss due to erosion. The remaining soil elevation loss was due to compaction from shallow subsidence. We found prolific growth of new fine rootlets (209 ± 34 SE g m−2) in the storm deposited material suggesting that deposits may become more stable in the near future (i.e., erosion rate will decrease). Surficial erosion and belowground processes both played an important role in determining the overall soil elevation. Expansion and contraction in the shallow soil zone may be due to hydrology, and in the middle and bottom soil zones due to shallow subsidence. Findings thus far indicate that soil elevation has made substantial gains compared to site specific relative sea-level rise, but data trends suggest that belowground processes, which differ by soil zone, may come to dominate the long term ecological impact of storm deposit.

  5. TUM Critical Zone Observatory, Germany

    NASA Astrophysics Data System (ADS)

    Völkel, Jörg; Eden, Marie

    2014-05-01

    Founded 2011 the TUM Critical Zone Observatory run by the Technische Universität München and partners abroad is the first CZO within Germany. TUM CZO is both, a scientific as well as an education project. It is a watershed based observatory, but moving behind this focus. In fact, two mountainous areas are integrated: (1) The Ammer Catchment area as an alpine and pre alpine research area in the northern limestone Alps and forelands south of Munich; (2) the Otter Creek Catchment in the Bavarian Forest with a crystalline setting (Granite, Gneiss) as a mid mountainous area near Regensburg; and partly the mountainous Bavarian Forest National Park. The Ammer Catchment is a high energy system as well as a sensitive climate system with past glacial elements. The lithology shows mostly carbonates from Tertiary and Mesozoic times (e.g. Flysch). Source-to-sink processes are characteristic for the Ammer Catchment down to the last glacial Ammer Lake as the regional erosion and deposition base. The consideration of distal depositional environments, the integration of upstream and downstream landscape effects are characteristic for the Ammer Catchment as well. Long term datasets exist in many regards. The Otter Creek catchment area is developed in a granitic environment, rich in saprolites. As a mid mountainous catchment the energy system is facing lower stage. Hence, it is ideal comparing both of them. Both TUM CZO Catchments: The selected catchments capture the depositional environment. Both catchment areas include historical impacts and rapid land use change. Crosscutting themes across both sites are inbuilt. Questions of ability to capture such gradients along climosequence, chronosequence, anthroposequence are essential.

  6. Factors Affecting Internal Blast

    NASA Astrophysics Data System (ADS)

    Granholm, R. H.; Sandusky, H. W.; Felts, J. E.

    2007-12-01

    Internal blast refers to explosion effects in confined spaces, which are dominated by the heat output of the explosive. Theoretical temperatures and pressures may not be reached due to heat losses and incomplete gas mixing. Gas mixing can have the largest effect, potentially reducing peak quasi-static pressure by a factor of two due to lack of thermal equilibrium between products and atmosphere in the space, separate from the effect of incomplete combustion of excess fuel when that atmosphere is air. Chamber and test geometry affect gas mixing, which has been inferred through temperature and pressure measurements and compared to calculations. Late-time combustion is observed for TNT compared to HMX.

  7. War zone paediatrics in Rwanda.

    PubMed

    Pearn, J

    1996-08-01

    Children are particularly vulnerable to injury and death in two types of 20th century conflicts; terrorist attack and civil war. This account describes some first-hand experiences of the aftermath of the Rwandan Civil War of 1994. Events leading to the conflict are described, eye witness accounts of child trauma during the war are recorded and the medical problems (currently ongoing) affecting children are described. Over a period of 3 months from April to June 1994, between half and one million Rwandese, a significant proportion of them women and children, were murdered in brutal hand-to-hand killing, dying from close-quarter gunshot and machete slaughter. Nearly half of the population became refugees in neighbouring countries or displaced persons in their own land. UNAMIR II, the United Nations Emergency Humanitarian Response, grew to some 7000 persons by May 1995. Medical aid was provided by emergency medical contingents from the United Kingdom, Canada and Australia, the latter through its Australian Medical Support Force, providing the definitive emergency medical infrastructure from August 1994. In the consequent post-war civil and social disruption, children suffered from burns, cholera and from motor vehicle trauma. Ongoing landmine blasts continue to affect children and adolescents especially. A new International humanitarian code to build a time-expiry device into landmines and other similar ordinance is urgently required as the post-conflict ongoing disasters in Rwanda, Afghanistan and Cambodia illustrate. Current problems affecting children include an increasing risk of HIV infection, trauma and the special humanitarian needs of thousands of orphans.

  8. War zone paediatrics in Rwanda.

    PubMed

    Pearn, J

    1996-08-01

    Children are particularly vulnerable to injury and death in two types of 20th century conflicts; terrorist attack and civil war. This account describes some first-hand experiences of the aftermath of the Rwandan Civil War of 1994. Events leading to the conflict are described, eye witness accounts of child trauma during the war are recorded and the medical problems (currently ongoing) affecting children are described. Over a period of 3 months from April to June 1994, between half and one million Rwandese, a significant proportion of them women and children, were murdered in brutal hand-to-hand killing, dying from close-quarter gunshot and machete slaughter. Nearly half of the population became refugees in neighbouring countries or displaced persons in their own land. UNAMIR II, the United Nations Emergency Humanitarian Response, grew to some 7000 persons by May 1995. Medical aid was provided by emergency medical contingents from the United Kingdom, Canada and Australia, the latter through its Australian Medical Support Force, providing the definitive emergency medical infrastructure from August 1994. In the consequent post-war civil and social disruption, children suffered from burns, cholera and from motor vehicle trauma. Ongoing landmine blasts continue to affect children and adolescents especially. A new International humanitarian code to build a time-expiry device into landmines and other similar ordinance is urgently required as the post-conflict ongoing disasters in Rwanda, Afghanistan and Cambodia illustrate. Current problems affecting children include an increasing risk of HIV infection, trauma and the special humanitarian needs of thousands of orphans. PMID:8844531

  9. Complex strain patterns developed at the frontal and lateral tips to shear zones and thrust zones

    NASA Astrophysics Data System (ADS)

    Coward, M. P.; Potts, G. J.

    Many of the complex strain patterns seen in shear zones and thrust zones, such as variable fabric orientations, refolded folds and fabrics, together with folds with hinges almost parallel to the main transport direction, can be explained in terms of differential movement within the shear zones. These strains are developed at the frontal and lateral tips of the zones as they propagate. Examples are taken from the Moine thrust zone of Scotland which show variations in strains particularly at the lateral tips. The form of differential movement described here may lead to complex strain paths and non-plane strain ellipsoids and the spatial variations in finite strain may be used to delineate zones of extensional and compressional flow and differential movement in the shear zones or thrusts.

  10. Formulating a coastal zone health metric for landuse impact management in urban coastal zones.

    PubMed

    Anilkumar, P P; Varghese, Koshy; Ganesh, L S

    2010-11-01

    The need for ICZM arises often due to inadequate or inappropriate landuse planning practices and policies, especially in urban coastal zones which are more complex due to the larger number of components, their critical dimensions, attributes and interactions. A survey of literature shows that there is no holistic metric for assessing the impacts of landuse planning on the health of a coastal zone. Thus there is a need to define such a metric. The proposed metric, CHI (Coastal zone Health Indicator), developed on the basis of coastal system sustainability, attempts to gauge the health status of any coastal zone. It is formulated and modeled through an expert survey and pertains to the characteristic components of coastal zones, their critical dimensions, and relevant attributes. The proposed metric is applied to two urban coastal zones and validated. It can be used for more coast friendly and sustainable landuse planning/masterplan preparation and thereby for the better management of landuse impacts on coastal zones.

  11. Teleseismic Tomography of the Eastern Tennessee Seismic Zone

    NASA Astrophysics Data System (ADS)

    Olasanmi, O. T.; Arroucau, P.; Vlahovic, G.

    2014-12-01

    In this work we perform a tomographic inversion of teleseismic data to investigate the properties of the crust and the uppermost mantle beneath the eastern Tennessee seismic zone (ETSZ). The ETSZ is a major seismic feature located in the southeastern United States. The zone spans portions of eastern Tennessee, North Carolina, Virginia, Georgia and Alabama and is, after the New Madrid seismic zone, the second most active seismic region of the North America east of the Rocky Mountains. Earthquakes in the ETSZ appear to align along a sharp, linear magnetic feature, called the New York-Alabama Lineament (NYAL), which acts as the northwest edge of the seismic zone and is attributed to a strike-slip fault affecting the Precambrian basement. A total of 2652 relative P-wave arrival time residuals from 201 teleseismic events recorded at 28 regional seismic station have been extracted from the continuous records using the adaptive stacking code. The three-dimensional model was computed down to 300km. The tomographic images show significant velocity anomalies, confirming complex tectonic evolution and revealing basement features that can be correlated with regional gravity and magnetic anomalies. One of the main features of the three-dimensional model is a significant velocity contrast across the NYAL that extends through the crust and the uppermost mantle, with high velocity anomalies northwest of the NYAL and lower velocities southwest of the NYAL. Our results support the hypothesis that the lineament is a major basement fault associated with a tectonic boundary produced by merging of the southern Appalachian basement with the Granite-Rhyolite basement during the Grenville orogeny.

  12. Growth dynamics of the seagrass Zostera japonica at its upper and lower distributional limits in the intertidal zone

    NASA Astrophysics Data System (ADS)

    Kim, Jong-Hyeob; Kim, Seung Hyeon; Kim, Young Kyun; Park, Jung-Im; Lee, Kun-Seop

    2016-06-01

    The seagrass Zostera japonica occurs mainly in the intertidal zone and is thus exposed to widely varying environmental conditions affecting its growth and distribution compared to subtidal seagrasses. The growth dynamics of Z. japonica at its upper and lower distributional limits in the intertidal zone were investigated in Koje Bay on the southern coast of Korea to examine the environmental stresses and limiting factors on the growth of intertidal seagrasses. The shoot density and morphology, biomass, and leaf productivity of Z. japonica were measured in relation to coincident measurements of environmental factors at its upper and lower distributional limits and in an intermediate zone of the intertidal area. The mean exposure time to the atmosphere during low tide in the upper intertidal zone was approximately 1.5- and 1.9-fold longer than that in the intermediate and lower intertidal zones, respectively. Shoot density and biomass were significantly higher in the intermediate zone than at the upper and lower distributional limits. Longer emersion leading to a various of environmental stresses appeared to reduce Z. japonica growth in the upper intertidal zone, whereas interspecific competitive interactions related to irradiance seemed to affect Z. japonica growth in the lower intertidal zone. Shoot size, density, biomass, and leaf productivity were lower in the upper than in the lower zone, implying that emersion-associated stresses in the upper zone had a greater detrimental effect on Z. japonica growth than did stresses occurring in the lower zone. The productivity of Z. japonica showed strong positive correlations with air and water temperature, suggesting enhancement of Z. japonica production at higher temperatures. Thus, the predicted increases in air and water temperature associated with global climate change might have positive effects on the growth and extension in distributional range of this species.

  13. Zones of Interaction: Differential Access to Elementary Science Discourse

    ERIC Educational Resources Information Center

    Shepardson, Daniel P.; Britsch, Susan Jane

    2006-01-01

    This study investigated teacher-child interaction within small-group science activities in a fourth-grade classroom. This qualitative study revealed three "zones of interaction," or teacher-child interaction categories: Individual Zones of Interaction, Multiple Zones of Interaction, and a Collective Zone of Interaction. Each zone was further…

  14. 9 CFR 77.22 - Accredited-free States or zones.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS Captive... tuberculosis, the State or zone may retain its accredited-free status. If two or more affected herds are... requirements contained in the “Uniform Methods and Rules—Bovine Tuberculosis Eradication” (January 22,...

  15. 9 CFR 77.9 - Modified accredited advanced States or zones.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at... TUBERCULOSIS Cattle and Bison § 77.9 Modified accredited advanced States or zones. (a) The following are... requirements contained in the “Uniform Methods and Rules—Bovine Tuberculosis Eradication” (January 22,...

  16. 9 CFR 77.9 - Modified accredited advanced States or zones.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at... TUBERCULOSIS Cattle and Bison § 77.9 Modified accredited advanced States or zones. (a) The following are... herd test requirements contained in the “Uniform Methods and Rules—Bovine Tuberculosis...

  17. 9 CFR 77.9 - Modified accredited advanced States or zones.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at... TUBERCULOSIS Cattle and Bison § 77.9 Modified accredited advanced States or zones. (a) The following are... herd test requirements contained in the “Uniform Methods and Rules—Bovine Tuberculosis...

  18. 9 CFR 77.9 - Modified accredited advanced States or zones.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at... TUBERCULOSIS Cattle and Bison § 77.9 Modified accredited advanced States or zones. (a) The following are... test requirements contained in the “Uniform Methods and Rules—Bovine Tuberculosis Eradication”...

  19. 9 CFR 77.22 - Accredited-free States or zones.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS Captive... tuberculosis, the State or zone may retain its accredited-free status. If two or more affected herds are... requirements contained in the “Uniform Methods and Rules—Bovine Tuberculosis Eradication” (January 22,...

  20. 9 CFR 77.22 - Accredited-free States or zones.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS Captive... tuberculosis, the State or zone may retain its accredited-free status. If two or more affected herds are... requirements contained in the “Uniform Methods and Rules—Bovine Tuberculosis Eradication” (January 22,...

  1. 9 CFR 77.22 - Accredited-free States or zones.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS Captive... tuberculosis, the State or zone may retain its accredited-free status. If two or more affected herds are... requirements contained in the “Uniform Methods and Rules—Bovine Tuberculosis Eradication” (January 22,...

  2. 9 CFR 77.22 - Accredited-free States or zones.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS Captive... tuberculosis, the State or zone may retain its accredited-free status. If two or more affected herds are... requirements contained in the “Uniform Methods and Rules—Bovine Tuberculosis Eradication” (January 22,...

  3. The Use of Radar Methods to Determine Moisture Content in the Vadose Zone

    SciTech Connect

    Knight, Rosemary

    2002-06-01

    Moisture content is a critical parameter affecting both liquid-phase and vapor-phase contaminant transport in the vadose zone. The objective of our three-year research project is to determine the optimal way to use radar methods as a non-invasive means of determining in situ moisture content.

  4. The Use of Radar Methods to Determine Moisture Content in the Vadose Zone

    SciTech Connect

    Knight, Rosemary

    2003-06-01

    Moisture content is a critical parameter affecting both liquid-phase and vapor-phase contaminant transport in the vadose zone. The objective of our three-year research project is to determine the optimal way to use radar methods as a non-invasive means of determining in situ moisture content.

  5. Influence of riparian seepage zones on nitrate variability in two agricultural headwater streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riparian seepage zones are one of the primary pathways of groundwater transport to headwater streams. While seeps have been recognized for their contributions to streamflow, there is little information on how seeps affect stream water quality. The objective of this study was to examine the influence...

  6. Factors controlling depth of continental rift zones

    NASA Astrophysics Data System (ADS)

    Elesin, Y.; Artemieva, I.; Thybo, H.

    2012-04-01

    Subsidence of continental rift basins is caused by thinning of the crust and lithospheric mantle together with isostatic compensation for the extra load of sediments and thermal relaxation. It is generally believed that the final depth of rift basins is primarily controlled by the amount of stretching and that other processes, such as rheology and sedimentation, only have secondary influence. However, we show that the relative rheological strength of faults inside and outside rift zones exerts substantial control on the volume of the final rift basin (by more than a factor of 3) even for the same amount of extension (total or inside the rift zone). This surprising result is mainly caused by irreversible deepening of the rift graben during stretching due to lower crustal flow when the faults in the rift zone are weak, whereas the effect is negligible for strong faults. Relatively strong faults inside the rift zone lead to substantial stretching of adjacent crust, and we find that long term stretching outside the main rift zone may explain the formation of wide continental margins, which are now below sea level. We also demonstrate that fast syn-rift erosion/sedimentation rates can increase the final volume of rift basins by up to a factor of 1.7 for weak crustal faults, whereas this effect is insignificant for strong faults inside the rift zone. These findings have significant implications for estimation of stretching factors, tectonic forces, and geodynamic evolution of sedimentary basins around failed rift zones.

  7. Seasonal affective disorder.

    PubMed

    Kurlansik, Stuart L; Ibay, Annamarie D

    2012-12-01

    Seasonal affective disorder is a combination of biologic and mood disturbances with a seasonal pattern, typically occurring in the autumn and winter with remission in the spring or summer. In a given year, about 5 percent of the U.S. population experiences seasonal affective disorder, with symptoms present for about 40 percent of the year. Although the condition is seasonally limited, patients may have significant impairment from the associated depressive symptoms. Treatment can improve these symptoms and also may be used as prophylaxis before the subsequent autumn and winter seasons. Light therapy is generally well tolerated, with most patients experiencing clinical improvement within one to two weeks after the start of treatment. To avoid relapse, light therapy should continue through the end of the winter season until spontaneous remission of symptoms in the spring or summer. Pharmacotherapy with antidepressants and cognitive behavior therapy are also appropriate treatment options and have been shown to be as effective as light therapy. Because of the comparable effectiveness of treatment options, first-line management should be guided by patient preference.

  8. Determining long time-scale hyporheic zone flow paths in Antarctic streams

    USGS Publications Warehouse

    Gooseff, M.N.; McKnight, Diane M.; Runkel, R.L.; Vaughn, B.H.

    2003-01-01

    hyporheic zones, in which slower biogeochemical reaction rates may affect stream-water chemistry at longer time-scales. Copyright ?? 2003 John Wiley & Sons, Ltd.

  9. Secondary porosity in a transient vadose zone

    SciTech Connect

    Frederick, W.T.; Grasso, T.X. Jr. )

    1993-03-01

    The Western New York Nuclear Service Center is the site of low and high level radioactive waster buried in a series of trenches excavated in a 28 m thick, Lavery-age silty clay diamicton that exhibits a 6 meter thick transient vadoes zone where exposed at the surface. Hydrostratigraphy of this till includes a 0.25 m thick poorly developed macroporous soil, a 3.5 m thick weathered zone of densely spaced and randomly orientated horizontal and vertical fractures, a 2 m thick unweathered zone of intermittently spaced fractures exhibiting east-west orientations, and a massive 23 m thick unweathered till zone that exhibits isolated, east-west orientated fractures. Bulk hydraulic conductivity of this active flow zone decreases with depth from 10[sup [minus]5] to 10[sup [minus]8] cm/s. The specific discharge of vertically flowing groundwater in the massive till zone is 1.25 cm/yr. A water surplus in the recharge season saturates the fractured zone to grade with up to 7.37 cm/yr of net infiltration. Tritium and radionuclides from the waste trenches and surrounding soil matrix hydrodynamically disperse into the field-saturated fracture network that contains meteoric recharge water. A soil moisture deficit in discharge season produces a vadose zone of widened fractures that via capillarity enhances the diffusion of contaminants into the soil matrix. These enlarged connecting conduits laterally channel the excess infiltration from the recharge season and diffused contaminants to local lowlands and incised streams that truncate the unweathered till. The current vadose and phreatic zone flow study will be used in numeric simulations that will delineate the areal extend and temporal duration of these seepage faces and the time frame of possible surfaces water contamination.

  10. Effect of aortic constriction on the functional border zone

    SciTech Connect

    Gallagher, K.P.; Ning, X.H.; Gerren, R.A.; Drake, D.H.; Dunham, W.R.

    1987-04-01

    To evaluate how aortic constriction affects nonischemic myocardium adjacent to the perfusion boundary (the functional border zone) the authors measured systolic wall thickening (dWT) with sonomicrometers in eight anesthetized, open-chest dogs. The locations of the wall thickening measurements relative to the perfusion boundary (PB) were determined with myocardial blood flow (radioactivity-labelled microspheres) maps constructed from multiple, small tissue samples. In nonischemic myocardium more than 10 mm from the PB produced by circumflex coronary occlusion, dWT increased significantly from 2.57 +/- 0.62 to 3.24 +/- 0.73 mm. Within 10 mm of the PB, however, dWT did not change significantly. When the aorta was mechanically constricted, peak systolic pressure increased approx.50%. Wall thickening decreased to the same relative degree in nonischemic muscle less than 10 mm and more than 10 mm from the perfusion boundary. By fitting sigmoid curves to the data, they estimated the extent of nonischemic dysfunction. It averaged 26 +/- 6/sup 0/ (6-8 mm of endocardial circumference) during coronary occlusion alone and it was not significantly different (29 +/- 11/sup 0/) after aortic constriction. Thus elevated afterload affects nonischemic myocardium uniformly and does not increase the size ore relative severity of the functional border zone.

  11. Can Solution Supersaturation Affect Protein Crystal Quality?

    NASA Technical Reports Server (NTRS)

    Gorti, Sridhar

    2013-01-01

    The formation of large protein crystals of "high quality" is considered a characteristic manifestation of microgravity. The physical processes that predict the formation of large, high quality protein crystals in the microgravity environment of space are considered rooted in the existence of a "depletion zone" in the vicinity of crystal. Namely, it is considered reasonable that crystal quality suffers in earth-grown crystals as a result of the incorporation of large aggregates, micro-crystals and/or large molecular weight "impurities", processes which are aided by density driven convective flow or mixing at the crystal-liquid interface. Sedimentation and density driven convection produce unfavorable solution conditions in the vicinity of the crystal surface, which promotes rapid crystal growth to the detriment of crystal size and quality. In this effort, we shall further present the hypothesis that the solution supersaturatoin at the crystal surface determines the growth mechanism, or mode, by which protein crystals grow. It is further hypothesized that protein crystal quality is affected by the mechanism or mode of crystal growth. Hence the formation of a depletion zone in microgravity environment is beneficial due to inhibition of impurity incorporatoin as well as preventing a kinetic roughening transition. It should be noted that for many proteins the magnitude of neither protein crystal growth rates nor solution supersaturation are predictors of a kinetic roughening transition. That is, the kinetic roughening transition supersaturation must be dtermined for each individual protein.

  12. 77 FR 21439 - Safety Zones; Annual Events Requiring Safety Zones in the Captain of the Port Lake Michigan Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-10

    ... Captain of the Port Lake Michigan Zone in the Federal Register (77 FR 11426). We received 0 letters... Thursday of November; 6 p.m. to 8 p.m. (66) New Years Eve Fireworks; Chicago, IL. (i) Location. All...

  13. Intergranular Corrosion Behavior of 304LN Stainless Steel Heat Treated at 623 K (350 °C)

    NASA Astrophysics Data System (ADS)

    Singh, Raghuvir; Kumar, Mukesh; Ghosh, Mainak; Das, Gautam; Singh, P. K.; Chattoraj, I.

    2013-01-01

    Low temperature sensitization of 304LN stainless steel from the two pipes, differing slightly in chemical composition, has been investigated; specimens were aged at 623 K (350 °C) for 20,000 hours and evaluated for intergranular corrosion and degree of sensitization. The base and heat-affected zone (HAZ) of the 304LN-1 appear resistant to sensitization, while 304LN-2 revealed a "dual" type microstructure at the transverse section and HAZ. The microstructure at 5.0-mm distance from the fusion line indicates qualitatively less sensitization as compared to that at 2.0 mm. The 304LN-2 base alloy shows overall lower degree of sensitization values as compared to the 304LN-1. A similar trend of degree of sensitization was observed in the HAZ where it was higher in the 304LN-1 as compared to the 304LN-2. The weld zone of both the stainless steels suffered from cracking during ASTM A262 practice E, while the parent metals and HAZs did not show such fissures. A mottled image within the ferrite lamella showed spinodal decomposition. The practice E test and transmission electron microscopy results indicate that the interdendritic regions may suffer from failure due to carbide precipitation and due to the evolution of brittle phase from spinodal decomposition.

  14. Mobile machine hazardous working zone warning system

    DOEpatents

    Schiffbauer, William H.; Ganoe, Carl W.

    1999-01-01

    A warning system is provided for a mobile working machine to alert an individual of a potentially dangerous condition in the event the individual strays into a hazardous working zone of the machine. The warning system includes a transmitter mounted on the machine and operable to generate a uniform magnetic field projecting beyond an outer periphery of the machine in defining a hazardous working zone around the machine during operation thereof. A receiver, carried by the individual and activated by the magnetic field, provides an alarm signal to alert the individual when he enters the hazardous working zone of the machine.

  15. Mobile machine hazardous working zone warning system

    DOEpatents

    Schiffbauer, W.H.; Ganoe, C.W.

    1999-08-17

    A warning system is provided for a mobile working machine to alert an individual of a potentially dangerous condition in the event the individual strays into a hazardous working zone of the machine. The warning system includes a transmitter mounted on the machine and operable to generate a uniform magnetic field projecting beyond an outer periphery of the machine in defining a hazardous working zone around the machine during operation. A receiver, carried by the individual and activated by the magnetic field, provides an alarm signal to alert the individual when he enters the hazardous working zone of the machine. 3 figs.

  16. Knowledge-based flow field zoning

    NASA Technical Reports Server (NTRS)

    Andrews, Alison E.

    1988-01-01

    Automation flow field zoning in two dimensions is an important step towards easing the three-dimensional grid generation bottleneck in computational fluid dynamics. A knowledge based approach works well, but certain aspects of flow field zoning make the use of such an approach challenging. A knowledge based flow field zoner, called EZGrid, was implemented and tested on representative two-dimensional aerodynamic configurations. Results are shown which illustrate the way in which EZGrid incorporates the effects of physics, shape description, position, and user bias in a flow field zoning.

  17. Magnetic Fields in the Solar Convection Zone

    NASA Astrophysics Data System (ADS)

    Fan, Yuhong

    2009-12-01

    Active regions on the solar surface are generally thought to originate from a strong toroidal magnetic field generated by a deep seated solar dynamo mechanism operating at the base of the solar convection zone. Thus the magnetic fields need to traverse the entire convection zone before they reach the photosphere to form the observed solar active regions. Understanding this process of active region flux emergence is therefore a crucial component for the study of the solar cycle dynamo. This article reviews studies with regard to the formation and rise of active region scale magnetic flux tubes in the solar convection zone and their emergence into the solar atmosphere as active regions.

  18. Making SPC easier with zone control charts

    SciTech Connect

    Lanning, B.

    1995-12-31

    The zone control chart is a simple, easy to learn statistical process control (SPC) tool that can be applied to any process where the data are normally distributed. Several Shewhart runs rules are incorporated into a simple scoring system, with a single rule to determine when a process is out of control. Zone charts have average run lengths (ARLs) for detecting shifts in the process mean which, for most cases, are uniformly better than the standard control charts. This paper presents the simplified methodology behind the zone control chart.

  19. Zone plate tilt study in transmission x-ray microscope system at 8-11 keV

    NASA Astrophysics Data System (ADS)

    Chao, Fu-Han; Yin, Gung-Chian; Liang, Keng S.; Lai, Yin-Chieh

    2009-08-01

    Zone plate [1] has been used as a focal lens in transmission X-ray microscope (TXM) optical system in recent decades [2, 3]. In TXM of NSRRC[4,5], the thickness of zone plate is about 900nm and the width of its out most zones is 50nm, which has a high aspect ratio 18. When zone plate is tilted, the image quality will be affected by aberration. Since the aspect ratio of zone plate is large, for incident beam, the shape of zone plate's transmission function will look different when zone plate is tilted. The both experimental and simulation result will be shown in this present. A five axes stage is designed and manufactured for the zone plate holder for three dimensional movement, tip and tilt. According to Fourier theory, we can calculate the wave distribution on image plane, if we know the original wave function, the distances between each element, and the transparencies of the sample and zone plate. A parallel simulation process code in MATLAB is developed in workstation cluster with up to 128Gbytes memory. The effects of aberration generated by tilt effect are compared from the experimental data and simulation result. A maximum tilt angle within the acceptable image quality is calculated by simulation and will be verified by experiment.

  20. En-face imaging of the ellipsoid zone in the retina from optical coherence tomography B-scans

    NASA Astrophysics Data System (ADS)

    Holmes, T.; Larkin, S.; Downing, M.; Csaky, K.

    2015-03-01

    It is generally believed that photoreceptor integrity is related to the ellipsoid zone appearance in optical coherence tomography (OCT) B-scans. Algorithms and software were developed for viewing and analyzing the ellipsoid zone. The software performs the following: (a), automated ellipsoid zone isolation in the B-scans, (b), en-face view of the ellipsoid-zone reflectance, (c), alignment and overlay of (b) onto reflectance images of the retina, and (d), alignment and overlay of (c) with microperimetry sensitivity points. Dataset groups were compared from normal and dry age related macular degeneration (DAMD) subjects. Scalar measurements for correlation against condition included the mean and standard deviation of the ellipsoid zone's reflectance. The imageprocessing techniques for automatically finding the ellipsoid zone are based upon a calculation of optical flow which tracks the edges of laminated structures across an image. Statistical significance was shown in T-tests of these measurements with the population pools separated as normal and DAMD subjects. A display of en-face ellipsoid-zone reflectance shows a clear and recognizable difference between any of the normal and DAMD subjects in that they show generally uniform and nonuniform reflectance, respectively, over the region near the macula. Regions surrounding points of low microperimetry (μP) sensitivity have nonregular and lower levels of ellipsoid-zone reflectance nearby. These findings support the idea that the photoreceptor integrity could be affecting both the ellipsoid-zone reflectance and the sensitivity measurements.

  1. Fracturing and rock pulverization along an exhumed seismogenic fault zone in dolostones: The Foiana Fault Zone (Southern Alps, Italy)

    NASA Astrophysics Data System (ADS)

    Fondriest, Michele; Aretusini, Stefano; Di Toro, Giulio; Smith, Steven A. F.

    2015-07-01

    The Foiana Fault Zone (FFZ) is a major sinistral transpressive fault zone exhumed from < 2 km depth in the Italian Southern Alps. The fault zone crosscuts thick sequences of sedimentary dolostones and shows increasing cumulative throw (0.3-1.8 km) moving from south to north along fault strike. The FFZ consists of variably fractured and fragmented dolostones locally cut by small-displacement (< 0.5 m) faults containing discrete, highly-reflective (so-called "mirror-like") slip surfaces. The mirror-like slip surfaces are typically embedded within fine-grained cataclasite layers up to a few centimeters thick. Preservation of bedding planes in the fragmented dolostones indicates a lack of significant shear strain. Instead, the fragmented dolostones are affected by in-situ shattering from the centimeter down to the micrometer scale, resembling pulverized rocks in crystalline lithologies. Detailed field and aerial structural mapping reveals significant changes in the structure of the FFZ along strike. In particular, the fault zone exhibits large variations in thickness (from c. 100 m in the north to more than 300 m in the south) and changes in mean fault orientation and fault kinematics (from dominant oblique- and strike-slip in the north to dip-slip reverse in the south), together with the reactivation of preexisting anisotropies (i.e. bedding). Overall, the structure of the FFZ, when considered together with possible variable exhumation levels along strike, compares favorably to the predicted damage distribution in three-dimensional earthquake rupture simulations on strike-slip faults, as well as to the characteristics of active seismic sources hosted in carbonate rocks as illuminated by recent seismological studies.

  2. The London low emission zone baseline study.

    PubMed

    Kelly, Frank; Armstrong, Ben; Atkinson, Richard; Anderson, H Ross; Barratt, Ben; Beevers, Sean; Cook, Derek; Green, Dave; Derwent, Dick; Mudway, Ian; Wilkinson, Paul

    2011-11-01

    On February 4, 2008, the world's largest low emission zone (LEZ) was established. At 2644 km2, the zone encompasses most of Greater London. It restricts the entry of the oldest and most polluting diesel vehicles, including heavy-goods vehicles (haulage trucks), buses and coaches, larger vans, and minibuses. It does not apply to cars or motorcycles. The LEZ scheme will introduce increasingly stringent Euro emissions standards over time. The creation of this zone presented a unique opportunity to estimate the effects of a stepwise reduction in vehicle emissions on air quality and health. Before undertaking such an investigation, robust baseline data were gathered on air quality and the oxidative activity and metal content of particulate matter (PM) from air pollution monitors located in Greater London. In addition, methods were developed for using databases of electronic primary-care records in order to evaluate the zone's health effects. Our study began in 2007, using information about the planned restrictions in an agreed-upon LEZ scenario and year-on-year changes in the vehicle fleet in models to predict air pollution concentrations in London for the years 2005, 2008, and 2010. Based on this detailed emissions and air pollution modeling, the areas in London were then identified that were expected to show the greatest changes in air pollution concentrations and population exposures after the implementation of the LEZ. Using these predictions, the best placement of a pollution monitoring network was determined and the feasibility of evaluating the health effects using electronic primary-care records was assessed. To measure baseline pollutant concentrations before the implementation of the LEZ, a comprehensive monitoring network was established close to major roadways and intersections. Output-difference plots from statistical modeling for 2010 indicated seven key areas likely to experience the greatest change in concentrations of nitrogen dioxide (NO2) (at least 3

  3. 'No Organics' Zone Circles Pinwheel

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Pinwheel galaxy, otherwise known as Messier 101, sports bright reddish edges in this new infrared image from NASA's Spitzer Space Telescope. Research from Spitzer has revealed that this outer red zone lacks organic molecules present in the rest of the galaxy. The red and blue spots outside of the spiral galaxy are either foreground stars or more distant galaxies.

    The organics, called polycyclic aromatic hydrocarbons, are dusty, carbon-containing molecules that help in the formation of stars. On Earth, they are found anywhere combustion reactions take place, such as barbeque pits and exhaust pipes. Scientists also believe this space dust has the potential to be converted into the stuff of life.

    Spitzer found that the polycyclic aromatic hydrocarbons decrease in concentration toward the outer portion of the Pinwheel galaxy, then quickly drop off and are no longer detected at its very outer rim. According to astronomers, there's a threshold at the rim where the organic material is being destroyed by harsh radiation from stars. Radiation is more damaging at the far reaches of a galaxy because the stars there have less heavy metals, and metals dampen the radiation.

    The findings help researchers understand how stars can form in these harsh environments, where polycyclic aromatic hydrocarbons are lacking. Under normal circumstances, the polycyclic aromatic hydrocarbons help cool down star-forming clouds, allowing them to collapse into stars. In regions like the rim of the Pinwheel as well as the very early universe stars form without the organic dust. Astronomers don't know precisely how this works, so the rim of the Pinwheel provides them with a laboratory for examining the process relatively close up.

    In this image, infrared light with a wavelength of 3.6 microns is colored blue; 8-micron light is green; and 24-micron light is red. All three of Spitzer's instruments were used in the study: the infrared array camera, the

  4. You can transform your HazMat policy.

    PubMed

    1999-11-01

    In addition to a protocol for everyday hazardous materials incidents, you need one for weapons of mass destruction, which include nuclear, chemical, or biologic agents. Direct minimally injured patients to a holding area. Have a plan for decontaminating hundreds or perhaps thousands of people. Have reference tables that list agents, symptoms, and the antidotes and decontamination supplies or various exposures.

  5. The changing world of HazMat transportation regulations

    SciTech Connect

    Ziebell, T. )

    1993-02-01

    The Hazardous Materials Regulations (HMR) have undergone considerable change since DOT's Research and Special Programs Administration (RSPA) issued its first rule for performance-oriented packaging standards (HM-181) on Dec. 21, 1990. Rules issued Dec. 20, 1991, and Oct. 1, 1992, corrected and modified amendments in the 1990 rule. Because the 1990 HM-181 amendments were so extensive -- and changes and corrections have been almost as extensive -- it is easy to understand why many people are confused by the new regulations. To complicate matters further, several HMR rules released in 1992 add requirements and compliance dates. While many employers are trying to learn the HM-181 amendments and train their employees, they must be aware of changes and requirements authorized by the 1992 rules.

  6. Advance assessment for movement of Haz Cat 3 radioactive materials.

    SciTech Connect

    Vosburg, Susan K.

    2010-04-01

    The current packaging of most HC-3 radioactive materials at SNL/NM do not meet DOT requirements for offsite shipment. SNL/NM is transporting HC-3 quantities of radioactive materials from their storage locations in the Manzano Nuclear Facilities bunkers to facilities in TA-5 to be repackaged for offsite shipment. All transportation of HC-3 rad material by SNL/NM is onsite (performed within the confines of KAFB). Transport is performed only by the Regulated Waste/Nuclear Material Disposition Department. Part of the HC3T process is to provide the CAT with the following information at least three days prior to the move: (1) RFt-Request for transfer; (2) HC3T movement report; (3) Radiological survey; and (4) Transportation Route Map.

  7. Haz-Map: Information on Hazardous Chemicals and Occupational Diseases

    MedlinePlus

    ... Occupational Diseases High Risk Jobs Non-Occupational Activities Industries Job Tasks Processes Symptoms/Findings Customer Service: tehip@teh.nlm.nih.gov Specialized Information Services U.S.National Library of Medicine, 8600 Rockville Pike, Bethesda, MD 20894 ...

  8. 33 CFR 165.154 - Safety and Security Zones; Captain of the Port Long Island Sound Zone Safety and Security Zones.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...; Captain of the Port Long Island Sound Zone Safety and Security Zones. 165.154 Section 165.154 Navigation... Long Island Sound Zone Safety and Security Zones. The following areas are designated safety and... navigable waters of Long Island Sound, from surface to bottom, North and Northeast of a line running...

  9. 33 CFR 165.154 - Safety and Security Zones: Long Island Sound Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Island Sound Marine Inspection Zone and Captain of the Port Zone. 165.154 Section 165.154 Navigation and... Areas First Coast Guard District § 165.154 Safety and Security Zones: Long Island Sound Marine... this zone is prohibited unless authorized by the Captain of the Port Long, Island Sound. (3)...

  10. 33 CFR 165.154 - Safety and Security Zones: Long Island Sound Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Island Sound Marine Inspection Zone and Captain of the Port Zone. 165.154 Section 165.154 Navigation and... Areas First Coast Guard District § 165.154 Safety and Security Zones: Long Island Sound Marine... this zone is prohibited unless authorized by the Captain of the Port Long, Island Sound. (3)...

  11. 33 CFR 165.154 - Safety and Security Zones; Captain of the Port Long Island Sound Zone Safety and Security Zones.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...; Captain of the Port Long Island Sound Zone Safety and Security Zones. 165.154 Section 165.154 Navigation... Long Island Sound Zone Safety and Security Zones. The following areas are designated safety and... navigable waters of Long Island Sound, from surface to bottom, North and Northeast of a line running...

  12. Vadose Zone Transport Field Study: Status Report

    SciTech Connect

    Gee, Glendon W.; Ward, Anderson L.

    2001-11-30

    Studies were initiated at the Hanford Site to evaluate the process controlling the transport of fluids in the vadose zone and to develop a reliable database upon which vadose-zone transport models can be calibrated. These models are needed to evaluate contaminant migration through the vadose zone to underlying groundwaters at Hanford. A study site that had previously been extensively characterized using geophysical monitoring techniques was selected in the 200 E Area. Techniques used previously included neutron probe for water content, spectral gamma logging for radionuclide tracers, and gamma scattering for wet bulk density. Building on the characterization efforts of the past 20 years, the site was instrumented to facilitate the comparison of nine vadose-zone characterization methods: advanced tensiometers, neutron probe, electrical resistance tomography (ERT), high-resolution resistivity (HRR), electromagnetic induction imaging (EMI), cross-borehole radar (XBR), and cross-borehole seismic (XBS). Soil coring was used to obtain soil samples for analyzing ionic and isotopic tracers.

  13. Strain accumulation along the Cascadia subduction zone

    USGS Publications Warehouse

    Murray, M.H.; Lisowski, M.

    2000-01-01

    We combine triangulation, trilateration, and GPS observations to determine horizontal strain rates along the Cascadia subduction zone from Cape Mendocino to the Strait of Juan de Fuca. Shear-strain rates are significantly greater than zero (95% confidence) in all forearc regions (26-167 nanoradians/yr), and are not significant in the arc and backarc regions. The deformation is primarily uniaxial contraction nearly parallel to Juan de Fuca-North America plate convergence (N55??-80??E). The strain rates are consistent with an elastic dislocation model for interseismic slip with a shallow 100-km wide locked zone and a deeper 75-km transition zone along the entire megathrust, except along the central Oregon coast where relatively lower strain rates are consistent with 30-40 km wide locked and transition zones.

  14. Strategic metal deposits of the Arctic Zone

    NASA Astrophysics Data System (ADS)

    Bortnikov, N. S.; Lobanov, K. V.; Volkov, A. V.; Galyamov, A. L.; Vikent'ev, I. V.; Tarasov, N. N.; Distler, V. V.; Lalomov, A. V.; Aristov, V. V.; Murashov, K. Yu.; Chizhova, I. A.; Chefranov, R. M.

    2015-11-01

    Mineral commodities rank high in the economies of Arctic countries, and the status of mineral resources and the dynamics of their development are of great importance. The growing tendency to develop strategic metal resources in the Circumarctic Zone is outlined in a global perspective. The Russian Arctic Zone is the leading purveyor of these metals to domestic and foreign markets. The comparative analysis of tendencies in development of strategic metal resources of the Arctic Zone in Russia and other countries is crucial for the elaboration of trends of geological exploration and research engineering. This paper provides insight into the development of Arctic strategic metal resources in global perspective. It is shown that the mineral resource potential of the Arctic circumpolar metallogenic belt is primarily controlled by large and unique deposits of nonferrous, noble, and rare metals. The prospective types of economic strategic metal deposits in the Russian Arctic Zone are shown.

  15. Density model of the Cascadia subduction zone

    USGS Publications Warehouse

    Romanyuk, T.V.; Mooney, W.D.; Blakely, R.J.

    2001-01-01

    The main goal of this work is to construct self-consistent density models along two profiles crossing the northern and central Cascadia subduction zone that have been comprehensively studied on the basis of geological, geophysical, etc. data.

  16. An interactive method for digitizing zone maps

    NASA Technical Reports Server (NTRS)

    Giddings, L. E.; Thompson, E. J.

    1975-01-01

    A method is presented for digitizing maps that consist of zones, such as contour or climatic zone maps. A color-coded map is prepared by any convenient process. The map is then read into memory of an Image 100 computer by means of its table scanner, using colored filters. Zones are separated and stored in themes, using standard classification procedures. Thematic data are written on magnetic tape and these data, appropriately coded, are combined to make a digitized image on tape. Step-by-step procedures are given for digitization of crop moisture index maps with this procedure. In addition, a complete example of the digitization of a climatic zone map is given.

  17. Advanced Vadose Zone Simulations Using TOUGH

    SciTech Connect

    Finsterle, S.; Doughty, C.; Kowalsky, M.B.; Moridis, G.J.; Pan,L.; Xu, T.; Zhang, Y.; Pruess, K.

    2007-02-01

    The vadose zone can be characterized as a complex subsurfacesystem in which intricate physical and biogeochemical processes occur inresponse to a variety of natural forcings and human activities. Thismakes it difficult to describe, understand, and predict the behavior ofthis specific subsurface system. The TOUGH nonisothermal multiphase flowsimulators are well-suited to perform advanced vadose zone studies. Theconceptual models underlying the TOUGH simulators are capable ofrepresenting features specific to the vadose zone, and of addressing avariety of coupled phenomena. Moreover, the simulators are integratedinto software tools that enable advanced data analysis, optimization, andsystem-level modeling. We discuss fundamental and computationalchallenges in simulating vadose zone processes, review recent advances inmodeling such systems, and demonstrate some capabilities of the TOUGHsuite of codes using illustrative examples.

  18. Pyroclastic passage zones in glaciovolcanic sequences.

    PubMed

    Russell, James K; Edwards, Benjamin R; Porritt, Lucy A

    2013-01-01

    Volcanoes are increasingly recognized as agents and recorders of global climate variability, although deciphering the linkages between planetary climate and volcanism is still in its infancy. The growth and emergence of subaqueous volcanoes produce passage zones, which are stratigraphic surfaces marking major transitions in depositional environments. In glaciovolcanic settings, they record the elevations of syn-eruptive englacial lakes. Thus, they allow for forensic recovery of minimum ice thicknesses. Here we present the first description of a passage zone preserved entirely within pyroclastic deposits, marking the growth of a tephra cone above the englacial lake level. Our discovery requires extension of the passage-zone concept to accommodate explosive volcanism and guides future studies of hundreds of glaciovolcanic edifices on Earth and Mars. Our recognition of pyroclastic passage zones increases the potential for recovering transient paleolake levels, improving estimates of paleo-ice thicknesses and providing new constraints on paleoclimate models that consider the extents and timing of planetary glaciations.

  19. Monitoring Vadose Zone Desiccation with Geophysical Methods

    SciTech Connect

    Truex, Michael J.; Johnson, Timothy C.; Strickland, Christopher E.; Peterson, John E.; Hubbard, Susan S.

    2013-05-01

    Soil desiccation was recently field tested as a potential vadose zone remediation technology. Desiccation removes water from the vadose zone and significantly decreases the aqueous-phase permeability of the desiccated zone, thereby decreasing movement of moisture and contaminants. The 2-D and 3-D distribution of moisture content reduction over time provides valuable information for desiccation operations and for determining when treatment goals have been reached. This type of information can be obtained through use of geophysical methods. Neutron moisture logging, cross-hole electrical resistivity tomography, and cross-hole ground penetrating radar approaches were evaluated with respect to their ability to provide effective spatial and temporal monitoring of desiccation during a treatability study conducted in the vadose zone of the DOE Hanford Site in WA.

  20. 30 CFR 250.272 - If a State objects to the DPP's or DOCD's coastal zone consistency certification, what can I do?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false If a State objects to the DPP's or DOCD's... objects to the DPP's or DOCD's coastal zone consistency certification, what can I do? If an affected State objects to the coastal zone consistency certification accompanying your proposed or disapproved DPP...