Science.gov

Sample records for age temperature burial

  1. Soil temperature calculation for burial site analysis.

    PubMed

    Prangnell, Jonathan; McGowan, Glenys

    2009-10-30

    The effect of air and water temperature upon the decomposition of human remains and upon biological activity has been extensively studied. However, less attention has been devoted to the temperature of the soil surrounding burials, despite its potential influence upon chemical reactions involved in the decomposition of human remains, drugs and toxins, as well as upon microbial and insect activity. A soil temperature calculation equation usually employed in civil engineering was used to calculate soil temperature at various depths in a cemetery located in Brisbane, Australia, in order to explain the extensive degradation of human remains and funerary objects observed at exhumation. The results showed that for the 160 years of the site's history, ground temperature at burial level had been sufficiently high for biological activity and chemical degradation reactions to continue right up until the time of exhumation. The equation used has potential in the analysis of both cemetery and clandestine burials, since it allows ground temperature to be calculated from ambient air temperature figures, for a variety of depths, soil types and vegetation conditions. PMID:19656646

  2. Distribution of maximum burial temperatures across northern Appalachian Basin and implications for Carboniferous sedimentation patterns

    SciTech Connect

    Johnsson, M.J.

    1986-05-01

    Clay-mineral diagenesis and apatite fission-track age data indicate that the maximum burial temperatures to which the Middle Devonian Tioga metabentonite was exposed rise abruptly from low values in western New York State to higher values in the east. The highest temperatures, which approach 175/sup 0/C, were reached just west of Syracuse. Neither the pattern nor the magnitude of burial temperatures can be explained solely by burial of the metabentonite beneath Upper Devonian sediments. Although spatial variations in the geothermal gradient could have produced the observed pattern of burial temperatures, it is more likely that Carboniferous sediments, no longer preserved in the area, were responsible for the indicated burial. The inferred presence of thick Carboniferous sequences in western New York State suggests that the Allegheny orogeny had a stronger influence on sedimentation in the northern Appalachian Basin than has been previously recognized. 25 references, 2 figures, 2 tables.

  3. Hypercapnia increases core temperature cooling rate during snow burial.

    PubMed

    Grissom, Colin K; Radwin, Martin I; Scholand, Mary Beth; Harmston, Chris H; Muetterties, Mark C; Bywater, Tim J

    2004-04-01

    Previous retrospective studies report a core body temperature cooling rate of 3 degrees C/h during avalanche burial. Hypercapnia occurs during avalanche burial secondary to rebreathing expired air, and the effect of hypercapnia on hypothermia during avalanche burial is unknown. The objective of this study was to determine the core temperature cooling rate during snow burial under normocapnic and hypercapnic conditions. We measured rectal core body temperature (T(re)) in 12 subjects buried in compacted snow dressed in a lightweight clothing insulation system during two different study burials. In one burial, subjects breathed with a device (AvaLung 2, Black Diamond Equipment) that resulted in hypercapnia over 30-60 min. In a control burial, subjects were buried under identical conditions with a modified breathing device that maintained normocapnia. Mean snow temperature was -2.5 +/- 2.0 degrees C. Burial time was 49 +/- 14 min in the hypercapnic study and 60 min in the normocapnic study (P = 0.02). Rate of decrease in T(re) was greater with hypercapnia (1.2 degrees C/h by multiple regression analysis, 95% confidence limits of 1.1-1.3 degrees C/h) than with normocapnia (0.7 degrees C/h, 95% confidence limit of 0.6-0.8 degrees C/h). In the hypercapnic study, the fraction of inspired carbon dioxide increased from 1.4 +/- 1.0 to 7.0 +/- 1.4%, minute ventilation increased from 15 +/- 7 to 40 +/- 12 l/min, and oxygen saturation decreased from 97 +/- 1 to 90 +/- 6% (P < 0.01). During the normocapnic study, these parameters remained unchanged. In this study, T(re) cooling rate during snow burial was less than previously reported and was increased by hypercapnia. This may have important implications for prehospital treatment of avalanche burial victims. PMID:14660514

  4. Diversity of burial rates in convergent settings decreased as Earth aged

    PubMed Central

    Nicoli, Gautier; Moyen, Jean-François; Stevens, Gary

    2016-01-01

    The evolution and the growth of the continental crust is inextricably linked to the evolution of Earth’s geodynamic processes. The detrital zircon record within the continental crust, as well as the isotopic composition of this crust, indicates that the amount of juvenile felsic material decreased with time and that in geologically recent times, the generation of new crust is balanced by recycling of the crust back into the mantle within subduction zones. However it cannot always have been so; yet the nature of the crust and the processes of crustal reworking in the Precambrian Earth are not well constrained. Here we use both detrital zircon ages and metamorphic pressure-temperature-time (P-T-t) information from metasedimentary units deposited in proposed convergent settings from Archaean, Proterozoic and Phanerozoic terrains to characterize the evolution of minimum estimates of burial rate (km.Ma−1) as a function of the age of the rocks. The demonstrated decrease in burial rate correlates positively with a progressive decrease in the production of juvenile felsic crust in the Archaean and Proterozoic. Burial rates are also more diverse in the Archaean than in modern times. We interpret these features to reflect a progressive decrease in the diversity of tectonic processes from Archaean to present, coupled with the emergence of the uniquely Phanerozoic modern-style collision. PMID:27216133

  5. Diversity of burial rates in convergent settings decreased as Earth aged

    NASA Astrophysics Data System (ADS)

    Nicoli, Gautier; Moyen, Jean-François; Stevens, Gary

    2016-05-01

    The evolution and the growth of the continental crust is inextricably linked to the evolution of Earth’s geodynamic processes. The detrital zircon record within the continental crust, as well as the isotopic composition of this crust, indicates that the amount of juvenile felsic material decreased with time and that in geologically recent times, the generation of new crust is balanced by recycling of the crust back into the mantle within subduction zones. However it cannot always have been so; yet the nature of the crust and the processes of crustal reworking in the Precambrian Earth are not well constrained. Here we use both detrital zircon ages and metamorphic pressure-temperature-time (P-T-t) information from metasedimentary units deposited in proposed convergent settings from Archaean, Proterozoic and Phanerozoic terrains to characterize the evolution of minimum estimates of burial rate (km.Ma‑1) as a function of the age of the rocks. The demonstrated decrease in burial rate correlates positively with a progressive decrease in the production of juvenile felsic crust in the Archaean and Proterozoic. Burial rates are also more diverse in the Archaean than in modern times. We interpret these features to reflect a progressive decrease in the diversity of tectonic processes from Archaean to present, coupled with the emergence of the uniquely Phanerozoic modern-style collision.

  6. Diversity of burial rates in convergent settings decreased as Earth aged.

    PubMed

    Nicoli, Gautier; Moyen, Jean-François; Stevens, Gary

    2016-01-01

    The evolution and the growth of the continental crust is inextricably linked to the evolution of Earth's geodynamic processes. The detrital zircon record within the continental crust, as well as the isotopic composition of this crust, indicates that the amount of juvenile felsic material decreased with time and that in geologically recent times, the generation of new crust is balanced by recycling of the crust back into the mantle within subduction zones. However it cannot always have been so; yet the nature of the crust and the processes of crustal reworking in the Precambrian Earth are not well constrained. Here we use both detrital zircon ages and metamorphic pressure-temperature-time (P-T-t) information from metasedimentary units deposited in proposed convergent settings from Archaean, Proterozoic and Phanerozoic terrains to characterize the evolution of minimum estimates of burial rate (km.Ma(-1)) as a function of the age of the rocks. The demonstrated decrease in burial rate correlates positively with a progressive decrease in the production of juvenile felsic crust in the Archaean and Proterozoic. Burial rates are also more diverse in the Archaean than in modern times. We interpret these features to reflect a progressive decrease in the diversity of tectonic processes from Archaean to present, coupled with the emergence of the uniquely Phanerozoic modern-style collision. PMID:27216133

  7. Time-temperature-burial significance of Devonian anthracite implies former great (approx. 6. 5 km) depth of burial of Catskill Mountains, New York

    SciTech Connect

    Friedman, G.M.; Sanders, J.E.

    1982-02-01

    Specimens of coalified plant debris in Tully-correlative strata of the Gilboa Formation (uppermost Middle Devonian) within the eastern Catskill Mountains of New York State have been converted to anthracite having a vitrinite reflectance of 2.5%. This implies a level of organic metamorphism (LOM) of 16. The specimens are about 350 m.y. old; if 200 m.y. is taken as the duration of the time of exposure to the maximum geothermal temperature, then the LOM of 16 and other thermal indicators imply a maximum temperature of 190/sup 0/C. Using a geothermal gradient of 26/sup 0/C.km/sup -1/ (17/sup 0/F.1,000 ft/sup -1/), a former depth of burial of 6.5 km is implied. Such former deep burial is not usually inferred for the Catskills, but it is consistent with the idea that the thick (about 6.4 km or 21,000 ft) Carboniferous strata of northeastern Pennsylvania formerly extended northeast far enough to bury the Catskills. The lack of metamorphism of the Paleozoic strata lying about 4.5 km beneath the Tully-correlative rocks and exposed in the adjacent Hudson Valley places low limits on the former geothermal gradient; this supports the concept of great depth of former burial of the Catskills. For example, 6.5 km of former burial and a geothermal gradient of 26/sup 0/C.km/sup -1/ imply a temperature of 307/sup 0/C for the base of the Paleozoic. By contrast, only 1 km of former burial requires a geothermal gradient of 170/sup 0/C.km/sup -1/, which would have subjected the base of the Paleozoic to a temperature of 955/sup 0/GAMMA, which is far higher than the 600 to 650/sup 0/C recently inferred for the Acadian-age metamorphism of the Taconic allochthon in southwestern Massachusetts and adjoining areas.

  8. Time-temperature-burial significance of Devonian anthracite implies former great (˜6.5 km) depth of burial of Catskill Mountains, New York

    NASA Astrophysics Data System (ADS)

    Friedman, Gerald M.; Sanders, John E.

    1982-02-01

    Specimens of coalified plant debris in Tully-correlative strata of the Gilboa Formation (uppermost Middle Devonian) within the eastern Cat-skill Mountains of New York State have been converted to anthracite having a vitrinite reflectance of 2.5%. This implies a level of organic metamorphism (LOM) of 16. A similar degree of thermal activity is implied by the black color (Staplin kerogen-alteration index of 4) of the associated (possibly recycled) carbonized kerogen, a conodont-alteration index of 4, and authigenic chlorite and local sericite fillings of the former interparticle pores of interbedded sandstones. The specimens are about 350 m.y. old; if 200 m.y. is taken as the duration of the time of exposure to the maximum geothermal temperature, then the LOM of 16 and other thermal indicators imply a maximum temperature of 190 °C. Using a geothermal gradient of 26 °C · km-1 (17 °F · 1,000 ft-1), a former depth of burial of 6.5 km is implied. Such former deep burial is not usually inferred for the Catskills, but it is consistent with the idea that the thick (about 6.4 km or 21,000 ft) Carboniferous strata of northeastern Pennsylvania formerly extended northeast far enough to bury the Catskills. The lack of metamorphism of the Paleozoic strata lying about 4.5 km beneath the Tully-correlative rocks and exposed in the adjacent Hudson Valley places low limits on the former geothermal gradient; this supports the concept of great depth of former burial of the Catskills. For example, 6.5 km of former burial and a geothermal gradient of 26 °C · km-1 imply a temperature of 307 °C for the base of the Paleozoic. By contrast, only 1 km of former burial requires a geothermal gradient of 170 °C · km-1, which would have subjected the base of the Paleozoic to a temperature of 955 °C, which is far higher than the 600 to 650 °C recently inferred for the Acadian-age metamorphism of the Taconic allochthon in southwestern Massachusetts and adjoining areas.

  9. Holocene age of the Yuha burial: Direct radiocarbon determinations by accelerator mass spectrometry

    USGS Publications Warehouse

    Stafford, Thomas W., Jr.; Jull, A.J.T.; Zabel, T.H.; Donahue, D.J.; Duhamel, R.C.; Brendel, K.; Haynes, C.V., Jr.; Bischoff, J.L.; Payen, L.A.; Taylor, R.E.

    1984-01-01

    The view that human populations may not have arrived in the Western Hemisphere before about 12,000 radiocarbon yr BP1,2 has been challenged by claims of much greater antiquity for a small number of archaeological sites and human skeleton samples. One such site is the Homo sapiens sapiens cairn burial excavated in 1971 from the Yuha desert, Imperial County, California3-5. Radiocarbon analysis of caliche coating one of the bones of the skeleton yielded a radiocarbon age of 21,500??1,000 yr BP4, while radiocarbon and uranium series analyses of caliche coating a cairn boulder yielded ages of 22,125??400 and 19,000??3,000 yr BP, respectively5. The late Pleistocene age assignment to the Yuha burial has been challenged by comparing the cultural context of the burial with other cairn burials in the same region6, on the basis of the site's geomorphological context and from radiocarbon analyses of soil caliches. 7,8 In rebuttal, arguments in defence of the original age assignment have been presented9,10 as well as an amino acid racemization analysis on the Yuha skeleton indicating an age of 23,600??2,600 yr BP11. The tandem accelerator mass spectrometer at the University of Arizona has now been used to measure the ratio of 14C/13C in several organic and inorganic fractions of post-cranial bone from the Yuha H. sapiens sapiens skeleton. Isotope ratios from six chemical fractions all yielded radiocarbon ages for the skeleton of less than 4,000 yr BP. These results indicate that the Yuha skeleton is of Holocene age, in agreement with the cultural context of the burial, and in disagreement with the previously assigned Pleistocene age of 19,000-23,000 yr. ?? 1984 Nature Publishing Group.

  10. A revised burial dose estimation procedure for optical dating of youngand modern-age sediments

    USGS Publications Warehouse

    Arnold, L.J.; Roberts, R.G.; Galbraith, R.F.; DeLong, S.B.

    2009-01-01

    The presence of genuinely zero-age or near-zero-age grains in modern-age and very young samples poses a problem for many existing burial dose estimation procedures used in optical (optically stimulated luminescence, OSL) dating. This difficulty currently necessitates consideration of relatively simplistic and statistically inferior age models. In this study, we investigate the potential for using modified versions of the statistical age models of Galbraith et??al. [Galbraith, R.F., Roberts, R.G., Laslett, G.M., Yoshida, H., Olley, J.M., 1999. Optical dating of single and multiple grains of quartz from Jinmium rock shelter, northern Australia: Part I, experimental design and statistical models. Archaeometry 41, 339-364.] to provide reliable equivalent dose (De) estimates for young and modern-age samples that display negative, zero or near-zero De estimates. For this purpose, we have revised the original versions of the central and minimum age models, which are based on log-transformed De values, so that they can be applied to un-logged De estimates and their associated absolute standard errors. The suitability of these 'un-logged' age models is tested using a series of known-age fluvial samples deposited within two arroyo systems from the American Southwest. The un-logged age models provide accurate burial doses and final OSL ages for roughly three-quarters of the total number of samples considered in this study. Sensitivity tests reveal that the un-logged versions of the central and minimum age models are capable of producing accurate burial dose estimates for modern-age and very young (<350??yr) fluvial samples that contain (i) more than 20% of well-bleached grains in their De distributions, or (ii) smaller sub-populations of well-bleached grains for which the De values are known with high precision. Our results indicate that the original (log-transformed) versions of the central and minimum age models are still preferable for most routine dating applications

  11. Resetting of RbSr ages of volcanic rocks by low-grade burial metamorphism

    USGS Publications Warehouse

    Asmeroma, Y.; Damon, P.; Shafiqullah, M.; Dickinson, W.R.; Zartman, R.E.

    1991-01-01

    We report a nine-point RbSr whole-rock isochron age of 70??3 Ma (MSWD 3.97) for Mid-Jurassic volcanic rocks. The same rocks have also been dated by the UThPb method on zircon, giving a crystallization age of 166 ?? 11 Ma, over twice as old as the RbSr age. The data demonstrate that whole-rock RbSr ages of volcanic rocks, even lava flows with SiO2 content as low as 57 wt.%, are susceptible to complete resetting. The rocks range in composition from rhyodacite tuffs to andesite lavas. The complete breakdown of all major minerals that contain Rb and Sr resulted in an alteration mineral assemblage consisting of phengite, albite, secondary quartz, and minor amounts of chlorite and epidote. Phengite is the K-bearing product of the breakdown of biotite and K-feldspar. Pressure during low-grade metamorphism of the volcanic rocks, estimated from phengite composition to have been in the range of 4 to 6 kbar, points to thrust-related burial as the main cause of resetting. Consequently, such reset isochrons may date large-scale events such as regional thrusting and metamorphism. The coherent resetting of the RbSr isochron suggests large-scale pervasive fluid movement during thrust-related burial metamorphism. ?? 1991.

  12. A paleolatitude approach to assessing surface temperature history for use in burial heating models

    USGS Publications Warehouse

    Barker, Charles E.

    2000-01-01

    Calculations using heat flow theory as well as case histories show that over geologic time scales (106 years), changes in mean annual surface temperature (Ts) on the order of 10°C penetrate kilometers deep into the crust. Thus, burial heating models of sedimentary basins, which typically span kilometers in depth and persist over geological time frames, should consider Ts history to increase their accuracy. In any case, Ts history becomes important when it changes enough to be detected by a thermal maturation index like vitrinite reflectance, a parameter widely used to constrain burial heating models. Assessment of the general temperature conditions leading to petroleum generation indicates that changes in Ts as small as 6°C can be detected by vitrinite reflectance measurements. This low temperature threshold indicates that oil and gas windows can be significantly influenced by Ts history. A review of paleoclimatic factors suggests the significant and geologically resolvable factors affecting Ts history are paleolatitude, long-term changes between cool and warm geological periods (climate mode), the degree to which a basin is removed from the sea (geographic isolation), and elevation or depth relative to sea level. Case studies using geologically realistic data ranges or different methods of estimating Ts in a burial heating model indicate a significant impact of Ts when: (1) continental drift, subduction, tectonism and erosion significantly change paleolatitude, paleoaltitude, or paleogeography; (2) strata are at, or near, maximum burial, and changes in Ts directly influence maximum burial temperature; and (3), when a significant change in Ts occurs near the opening or closing of the oil or gas windows causing petroleum generation to begin or cease. Case studies show that during the burial heating and petroleum generation phase of basin development changes in climate mode alone can influence Ts by about 15°C. At present, Ts changes from the poles to the equator

  13. The presence of nuclear families in prehistoric collective burials revisited: the bronze age burial of Montanissell Cave (Spain) in the light of aDNA.

    PubMed

    Simón, Marc; Jordana, Xavier; Armentano, Nuria; Santos, Cristina; Díaz, Nancy; Solórzano, Eduvigis; López, Joan B; González-Ruiz, Mercedes; Malgosa, Assumpció

    2011-11-01

    Ancient populations have commonly been thought to have lived in small groups where extreme endogamy was the norm. To contribute to this debate, a genetic analysis has been carried out on a collective burial with eight primary inhumations from Montanissell Cave in the Catalan pre-Pyrenees. Radiocarbon dating clearly placed the burial in the Bronze Age, around 3200 BP. The composition of the group-two adults (one male, one female), one young woman, and five children from both sexes-seemed to represent the structure of a typical nuclear family. The genetic evidence proves this assumption to be wrong. In fact, at least five out of the eight mitochondrial haplotypes were different, denying the possibility of a common maternal ancestor for all of them. Nevertheless, 50% of the inhumations shared haplogroup J, so the possibility of a maternal relationship cannot be ruled out. Actually, combining different analyses performed using ancient and living populations, the probability of having four related J individuals in Montanissell Cave would range from 0.9884 to 0.9999. Owing to the particularities of this singular collective burial (small number of bodies placed altogether in a hidden cave, the evidence of non-simultaneous interments, close dating and unusual grave goods), we suggest that it might represent a small group with a patrilocal mating system. PMID:21959902

  14. 26 Al - 10 Be burial ages of a Pleistocene Terrace in the Vienna Basin

    NASA Astrophysics Data System (ADS)

    Neuhuber, Stephanie; Braumann, Sandra; Lüthgens, Christopher; Schäfter, Jörg; Häuselmann, Philipp; Fiebig, Markus

    2015-04-01

    The Vienna Basin is a pull-apart basin located between the Eastern Alps and the Western Carpathians. Its main subsidence started in the Miocene and resulted in a maximum of 6 km sedimentary infill. Up to five Pleistocene terraces formed by the Danube river and its tributaries and are separated by their geometic cross cutting and topographic relationships. The ongoing tectonic displacement results in tilting of terrace levels and prevents the correlation of similar levels to one sedimentation event. For this reason absolute age dating is essential in this setting. This research applies 26Al/10Be isochrone dating of one selected Pleistocene Terrace, the Gänserndorf terrace at two different sampling sites. This terrace has already a numerical age determined by OSL age of 250 +/- 50 kyr. Isochrone age dating may be used for samples with different transport histories and exposition duration that share the same last burial event and is ideal for the sedimentary setting of the terrace gravels of the Gänserndorf terrace. The source area of the terrace consists mainly of metamorphic rocks that contain large quartz pebbles that are suitable for cosmogenic 26Al and 10Be extraction.

  15. 26Al/10Be burial ages for a Pleistocene terrace in the Vienna Basin, Austria

    NASA Astrophysics Data System (ADS)

    Braumann, S.; Fiebig, M.; Neuhuber, S.; Schaefer, J. M.; Haeuselmann, P.; Schwartz, R.; Finkel, R. C.

    2014-12-01

    The Vienna Basin in the northeastern part of Austria between the Eastern Alps and the West Carpathians is a pull-apart basin crossed by the Danube river. The structure is filled with marine and terrestrial sediments showing thicknesses of up to 6 km. An increase in glacial melt water discharges, typically linked to high productivity of Alpine glaciers, had an essential impact on the formation of the investigated terrace. The scale of erosion and sediment transport translates to deposition rates in the foreland and is influenced by the magnitude of melt water discharges in Alpine catchment areas. Variations in layer characteristics (i.e. grain size, sorting, thickness) are an indicator for glacial pulses. Burial dates of ten quartz pebbles originating from the Gaenserndorfer terrace, situated in the northeastern part of the basin, set time dependent constraints on the required hydrological regime for mobilization, transport and sedimentation of bedloads and allow relating the deposition of glacial sediments to past glacial periods. But the geomorphic evolution of the Vienna Basin was not only determined by sedimentation processes. A number of irregularities manifest that tectonics affected the area as well: Terrace tilts are dipping against the slope of the Danube and offsets of some decameters between sediment layers showing the same facies, but located several kilometers apart from each other, could be identified. An extensive Miocene fault system was partly reactivated during the Middle Pleistocene and could have caused the formation of these discontinuities. It is of great interest to discriminate impacts on the area due to deposition from morphological elements formed by seismic events. The preliminary burial ages afford for putting the sampled terrace segment into a coherent geochronological context and provide a dataset to compare ages of the Gaenserndofer terrace to ages of sediment layers at other locations within the basin in order to either validate or

  16. Dating the incision of the Yangtze River gorge at the First Bend using three-nuclide burial ages

    NASA Astrophysics Data System (ADS)

    McPhillips, Devin; Hoke, Gregory D.; Liu-Zeng, Jing; Bierman, Paul R.; Rood, Dylan H.; Niedermann, Samuel

    2016-01-01

    Incision of the Yangtze River gorge is widely interpreted as evidence for lower crustal flow beneath the southeast margin of the Tibetan Plateau. Previous work focused on the onset of incision, but the duration of incision remains unknown. Here we present cosmogenic nuclide burial ages of sediments collected from caves on the walls of the gorge that show the gorge was incised ~1 km sometime between 18 and 9 Ma. Thereafter, incision slowed substantially. We resolve middle Miocene burial ages by using three nuclides and accounting for in situ muogenic production. This approach explains the absolute concentrations of 10Be, 26Al, and 21Ne, as well as 26Al/10Be and 21Ne/10Be ratios. A declining incision rate challenges existing geodynamic interpretations by suggesting that either (1) surface uplift has ceased immediately south of the plateau margin or (2) gorge incision is not a useful proxy for the timing of surface uplift.

  17. LIDAR-based coastal landscape reconstruction and harbour location: The Viking-age royal burial site of Borre (Norway)

    NASA Astrophysics Data System (ADS)

    Draganits, Erich; Doneus, Michael; Gansum, Terje

    2013-04-01

    Airborne light detection and ranging (LIDAR) has found wide application in archaeological research for the detection and documentation of archaeological and palaeo-environmental features. In this study we demonstrate the analysis of an LIDAR derived 1x1 m digital elevation model (DTM) combined with geoarchaeological research of the coastal Viking-age burial site in Borre, Olso Fjord (Norway). Borre is an exceptional burial site in Scandinavia, containing burial mounds up to 40 m in diameter and 6 m height, mentioned in Nordic Sagas, especially in the skaldic poem Ynglingatal, as the burial place of one or two kings of the Ynglinga dynasty. Archaeological findings and radiocarbon ages indicate that the Borre burial ground had been in use broadly between 600-1000 AD. Despite the reasonable expectation that a coastal site connected with the Viking kings of Vestfold, with hall buildings and ship graves demands a harbour, up to now no harbour has not been found with traditional archaeological surveys. Since the area of Borre is affected by a continuous land uplift related to glacial rebound of Scandinavia, any former harbour site is expected to be exposed to the land surface today. The present day vertical crustal uplift is calculated around 2.5 mm/yr in the area of Borre. Burial mounds and surrounding borrow pits as well as geomorphological features of the uplifted coast of Borre have been analysed by the 1x1 m LIDAR-DTM, using hillshade, slope and local relief model for visualisation. Altogether, 41 burial mounds and further 6 potential mounds are visible in the high-resolution DTM. A succession of more than 14 beach ridges, cross-cut by the burial mounds, is visible from the present shore line up to 18 m asl. They are more or less parallel and similar in size, except between at ca. 4-6 m asl, where the most prominent ridge is located, which probably has been enforced artificially. Using published shoreline displacement curves from nearby areas, the shore-line at

  18. [Skeleton or mummy: practices and structures for secondary burial in southern Italy in modern and contemporary age].

    PubMed

    Fornaciari, Antonio

    2013-01-01

    The ancient concepts of death as duration and the practices of secondary burial,first analysed by Robert Hertz, still survive in many areas of southern Italy. According to these beliefs death was perceived not as a sudden event, but as a long-lasting process, during which the deceased person had to go through a transitory phase, passing from one state of existence to another. Recent archeological research documents the persistence of secondary burial rites in Southern Italy during the Modern Age. A survey conducted in the province of Messina in Eastern Sicily has identified two surviving architectural structures appointed for the treatment of the bodies: the 'sitting colatoio' aimed at favoring the skeletonisation and the 'horizontal colatoio' used to obtain mummification by dehydration. Both these structures controlled the corpse's decay and transformed the body in a stable and durable simulacra of the dead. PMID:25807706

  19. 40Ar/39Ar incremental heating experiments on celadonite from the Skessa Tuff, eastern Iceland: Thermochronology of low-temperature alteration of a flood basalt pile during burial metamorphism

    NASA Astrophysics Data System (ADS)

    Riishuus, M. S.; Miggins, D. P.; Koppers, A. A. P.; Duncan, R. A.

    2014-12-01

    Celadonite is a low-temperature (<~50 °C) alteration mineral that fills voids and fractures within buried and metasomatized volcanic rocks. The common occurrence, mineral chemistry and structural properties of celadonite (a K2O-rich and Ar retentive phyllosilicate) make it attractive as a monitor of not only spatial and temporal variability of low-temperature hydrothermal fluid circulation and alteration, but also potentially of burial rates of lava piles. The Neogene lava pile in E Iceland underwent burial metamorphism, tectonic tilting and subsequent glacial exhumation, and is today exposed with superimposed sub-horizontal regional zeolite facies mineral zones. From a single sample of the Skessa Tuff, a prominent welded pyroclastic flow, we present new 40Ar/39Ar incremental heating age determinations using the ARGUS-VI multi-collector mass spectrometer at OSU: plagioclase (10.26 ± 0.12 Ma), groundmass (10.15 ± 0.10 Ma), early-forming light green celadonite (9.73 ± 0.03 Ma) and later-forming dark blue-green celadonite (9.67 ± 0.03). The sample was collected at ~500 m above sea level (masl), beneath volcanic material from the Thingmuli dyke swarm and central volcano. The cooling ages of plagioclase and groundmass separates are in close agreement and represent the eruption age of this pyroclastic flow. The geochronologic data and petrographic observations suggest homogeneous and relatively rapid crystallization of celadonite. The inferred original top of the lava pile is ~650 m (1400 masl, and lost to erosion) above the top of the analcime zone (~750 masl). Celadonite is predominantly found as early-stage lining of primary pore space, but overgrown by chlorite/smectite clays and zeolites at higher grades. Above ~750 mals vesicles are void of celadonite, and hence, celadonite precipitates in a narrow zone at ~650 m depth. The pyroclastic flow and its subsequent burial to ~650 m depth is separated by ~600 ky, which suggests a burial rate of ~1100 m/m.y. This

  20. New cosmogenic burial ages for Sterkfontein Member 2 Australopithecus and Member 5 Oldowan.

    PubMed

    Granger, Darryl E; Gibbon, Ryan J; Kuman, Kathleen; Clarke, Ronald J; Bruxelles, Laurent; Caffee, Marc W

    2015-06-01

    The cave infills at Sterkfontein contain one of the richest assemblages of Australopithecus fossils in the world, including the nearly complete skeleton StW 573 ('Little Foot') in its lower section, as well as early stone tools in higher sections. However, the chronology of the site remains controversial owing to the complex history of cave infilling. Much of the existing chronology based on uranium-lead dating and palaeomagnetic stratigraphy has recently been called into question by the recognition that dated flowstones fill cavities formed within previously cemented breccias and therefore do not form a stratigraphic sequence. Earlier dating with cosmogenic nuclides suffered a high degree of uncertainty and has been questioned on grounds of sediment reworking. Here we use isochron burial dating with cosmogenic aluminium-26 and beryllium-10 to show that the breccia containing StW 573 did not undergo significant reworking, and that it was deposited 3.67 ± 0.16 million years ago, far earlier than the 2.2 million year flowstones found within it. The skeleton is thus coeval with early Australopithecus afarensis in eastern Africa. We also date the earliest stone tools at Sterkfontein to 2.18 ± 0.21 million years ago, placing them in the Oldowan at a time similar to that found elsewhere in South Africa at Swartkans and Wonderwerk. PMID:25830884

  1. New cosmogenic burial ages for Sterkfontein Member 2 Australopithecus and Member 5 Oldowan

    NASA Astrophysics Data System (ADS)

    Granger, Darryl E.; Gibbon, Ryan J.; Kuman, Kathleen; Clarke, Ronald J.; Bruxelles, Laurent; Caffee, Marc W.

    2015-06-01

    The cave infills at Sterkfontein contain one of the richest assemblages of Australopithecus fossils in the world, including the nearly complete skeleton StW 573 (`Little Foot') in its lower section, as well as early stone tools in higher sections. However, the chronology of the site remains controversial owing to the complex history of cave infilling. Much of the existing chronology based on uranium-lead dating and palaeomagnetic stratigraphy has recently been called into question by the recognition that dated flowstones fill cavities formed within previously cemented breccias and therefore do not form a stratigraphic sequence. Earlier dating with cosmogenic nuclides suffered a high degree of uncertainty and has been questioned on grounds of sediment reworking. Here we use isochron burial dating with cosmogenic aluminium-26 and beryllium-10 to show that the breccia containing StW 573 did not undergo significant reworking, and that it was deposited 3.67 +/- 0.16 million years ago, far earlier than the 2.2 million year flowstones found within it. The skeleton is thus coeval with early Australopithecus afarensis in eastern Africa. We also date the earliest stone tools at Sterkfontein to 2.18 +/- 0.21 million years ago, placing them in the Oldowan at a time similar to that found elsewhere in South Africa at Swartkans and Wonderwerk.

  2. 21Ne, 10Be and 26Al cosmogenic burial ages of near-surface eolian sand from the Packard Dune field, McMurdo Dry Valleys, Antarctica.

    NASA Astrophysics Data System (ADS)

    Fink, David; Augustinus, Paul; Rhodes, Ed; Bristow, Charles; Balco, Greg

    2015-04-01

    The McMurdo Dry Valleys, Antarctica, have been ice-free for at least 10 Ma. In Victoria Valley, the largest of the Dry Valleys, permafrosted yet still actively migrating dune-fields, occupy an area of ~8 km2 with dune thicknesses varying from ~5 to 70 meters. High-resolution ground penetrating radar (GPR) imaging of selected dunes reveal numerous unconformities and complex stratigraphy inferring cycles of sand accretion and deflation from westerly katabatic winter winds sourced from the East Antarctic Ice Sheet and anabatic summer winds sourced from the Ross Sea. Samples above permafrost depth were taken for OSL and cosmogenic 26Al/10Be burial ages. OSL ages from shallow (<1m) pits range from modern to ~1.3ka suggesting that deposition/reworking of the dunes is on-going and their present configuration is a late Holocene feature. The same 7 samples gave a mean 26Al/10Be = 4.53 +/- 5% with an average apparent continuous 10Be surface exposure age of 525 +/- 25 ka surprisingly indicating a common pre-history independent of depth. Correcting for minor post-burial production based on OSL ages, the minimum (integrated) burial period for these sand grains is 0.51+/- 0.12 Ma which represents the burial age at the time of arrival at the dune. A possible explanation is that this common burial signal reflects recycling episodes of exposure, deposition, burial and deflation, sufficiently frequent to move all grains towards a common pre-dune deposition history. However, it is unclear over what length of time this processes has been active and fraction of time the sand has been buried. Consequently we also analysed purified quartz aliquots of the same samples for a third and stable nuclide, 21Ne, to determine the total surface and burial exposure periods. Using the 21Ne/10Be system we obtain burial ages of 1.10 +/- 0.10 Ma. Further coring below permafrost is planned for austral summer 2015.

  3. Symbolic Metal Bit and Saddlebag Fastenings in a Middle Bronze Age Donkey Burial

    PubMed Central

    Bar-Oz, Guy; Nahshoni, Pirhiya; Motro, Hadas; Oren, Eliezer D.

    2013-01-01

    Here we report the unprecedented discovery of the skeleton of a ritually interred donkey with a metal horse bit in association with its teeth and saddlebag fastenings on its back. This discovery in the Middle Bronze Age III sacred precinct (1700/1650-1550 BCE) at Tel Haror, Israel, presents a unique combination of evidence for the early employment of equid harnessing equipment, both for chariot bridling (horse bit) and pack animals (saddlebags). The ritually deposited donkey with its unique accoutrements advances our understanding of the broad social and religious significance of equids in the Levantine Bronze Age, previously known mainly from textual and iconographical sources. PMID:23484046

  4. A practical approach to reconstructing burial and temperature histories: An example from the Mobil O`Connel well, Piceance Basin, Colorado

    SciTech Connect

    Laughland, M.M.

    1996-12-31

    The O`Connell well was drilled about five years ago as part of a deep basin, tight gas play. The well penetrates a Devonian through Paleocene age section of carbonate and clastic lithologies. Fifty-five m.y. old strata of the Wasatch Formation are exposed at the surface. A multidisciplinary empirical approach was used to determine the magnitude and timing of maximum temperature and paleogeothermal gradient, as well as uplift and erosion, independent of numerical basin modeling. Apatite fission track analysis (AFTA) indicates that 1.36 km. (4,460 ft.) of section were eroded beginning at {approx}5 Ma., which was synchronous with the timing of uplift of the Colorado Plateau. The timing of maximum temperature at {approximately}27 Ma. was determined using {sup 40}Ar/{sup 39}Ar thermochronology and was synchronous with the timing of local igneous activity and mineralization of the Colorado Mineral Belt. Maximum paleotemperatures based on %R{sub o} and pressure corrected homogenization temperatures from fluid inclusions in quartz veins are as high as 340{degrees}C (644{degrees}F), or about 100{degrees}C higher than present-day maximum temperature. Calculations of maximum paleogeothermal gradient equal {approx}52{degrees}C/km. (3.03{degrees}C/100ft.) This multiple thermal indicator approach to the analysis of cuttings and core limits the number of possible burial and thermal history scenarios, thereby reducing much of the uncertainty in basin history reconstructions.

  5. The Influence of Organic Material and Temperature on the Burial Tolerance of the Blue Mussel, Mytilus edulis: Considerations for the Management of Marine Aggregate Dredging

    PubMed Central

    Cottrell, Richard S.; Black, Kenny D.; Hutchison, Zoë L.; Last, Kim S.

    2016-01-01

    Rationale and Experimental Approach Aggregate dredging is a growing source of anthropogenic disturbance in coastal UK waters and has the potential to impact marine systems through the smothering of benthic fauna with organically loaded screening discards. This study investigates the tolerance of the blue mussel, Mytilus edulis to such episodic smothering events using a multi-factorial design, including organic matter concentration, temperature, sediment fraction size and duration of burial as important predictor variables. Results and Discussion Mussel mortality was significantly higher in organically loaded burials when compared to control sediments after just 2 days. Particularly, M. edulis specimens under burial in fine sediment with high (1%) concentrations of organic matter experienced a significantly higher mortality rate (p<0.01) than those under coarse control aggregates. Additionally, mussels exposed to the summer maximum temperature treatment (20°C) exhibited significantly increased mortality (p<0.01) compared to those in the ambient treatment group (15°C). Total Oxygen Uptake rates of experimental aggregates were greatest (112.7 mmol m-2 day-1) with 1% organic loadings in coarse sediment at 20°C. Elevated oxygen flux rates in porous coarse sediments are likely to be a function of increased vertical migration of anaerobically liberated sulphides to the sediment-water interface. However, survival of M. edulis under bacterial mats of Beggiatoa spp. indicates the species’ resilience to sulphides and so we propose that the presence of reactive organic matter within the burial medium may facilitate bacterial growth and increase mortality through pathogenic infection. This may be exacerbated under the stable interstitial conditions in fine sediment and increased bacterial metabolism under high temperatures. Furthermore, increased temperature may impose metabolic demands upon the mussel that cannot be met during burial-induced anaerobiosis. Summary Lack of

  6. An Early Cretaceous garnet pressure-temperature path recording synconvergent burial and exhumation from the hinterland of the Sevier orogenic belt, Albion Mountains, Idaho

    NASA Astrophysics Data System (ADS)

    Kelly, Eric D.; Hoisch, Thomas D.; Wells, Michael L.; Vervoort, Jeffrey D.; Beyene, Mengesha A.

    2015-08-01

    Rocks may undergo complex pressure-temperature ( P- T) histories during orogenesis in response to alternating episodes of synconvergent burial and exhumation. In this study, chemical zoning in garnets combined with textural and chemical evidence from the schist of Willow Creek in the Albion Mountains of south-central Idaho (USA), reveals a complex P- T path during the early stages of Sevier orogenesis. The distribution of quartz inclusions combined with internal resorption features establishes a hiatus in garnet growth. Chemical zoning was simulated using a G-minimization approach to yield a P- T path consisting of three distinct pressure changes during increasing temperature, defining an "N" shape. Lu-Hf isochron ages from multiple garnet fractions and whole-rock analyses in two samples are 132.1 ± 2.4 and 138.7 ± 3.5 Ma. The samples were collected from the hanging wall of the Basin-Elba thrust fault and yielded results similar to those previously obtained from the footwall. This leads to several conclusions: (1) Both the hanging wall and footwall experienced the same metamorphic event, (2) the paths document a previously unrecognized crustal thickening and synorogenic extension cycle that fills an important time gap in the shortening history of the Sevier retroarc, suggesting progressive eastward growth of the orogen rather than a two-stage history, and (3) episodes of extensional exhumation during protracted convergent orogenesis are increasingly well recognized and highlight the dynamic behavior of orogenic belts.

  7. Predicted temperature/time histories resulting from the burial of nuclear waste canisters in bedded salt

    SciTech Connect

    George, O.L. Jr.

    1980-07-01

    This report provides computed thermal mappings for bedded salt surrounding canisters containing nuclear waste. This information can be used to study the possible migration of fluids within bedded salt under the influence of thermal gradients created by the heat-generating nuclear waste. The results presented were obtained from CINDA thermal models. Three different drift/canister configurations were modeled. The thermal conductivity of the salt was assumed to be temperature dependent while both the density and specific heat were assumed to be constant. Thermal power densities of 30, 75, and 150 kW/acre were examined with canister powers of 0.581 kW (51.6 canisters/acre), 3.5 kW (21.4 canisters/acre), and 3.5 kW (42.9 canisters/acre) at emplacement, respectively. These three cases resulted in maximum salt temperatures of 55/sup 0/C, 117/sup 0/C, and 176/sup 0/C, respectively; and maximum thermal gradients of -15/sup 0/C/m, -63/sup 0/C/m, and -101/sup 0/C/m, respectively. Computer-generated plots of temperature versus distance in horizontal planes at the top, midpoint, and bottom of the canister were made for several times after emplacement. Logarithmic or linear equations (whichever provided the better fit) were used to describe these curves. Derivatives of temperature with respect to distance were then taken and results of the form x(dT/dx) and dT/dx for the logarithmic and linear equations, respectively, were plotted against time. For the two cases where the waste thermal outputs decayed exponentially, it was found that x(dT/dx) and dT/dx were linear functions of time over a large period of years.

  8. Temperature calibration of amino acid racemization: age implications for the Yuha skeleton

    USGS Publications Warehouse

    Bischoff, J.L.; Childers, W.M.

    1979-01-01

    D/L of aspartic acid ranged from 0.52 to 0.56 for femur samples of the Yuha skeleton. Subsurface temperature measurements made at the burial site indicate average annual temperature is 18??C and diagenetic temperature is 21.6??C. These data and a relation derived for the dependence of the aspartic acid rate constant on diagenetic temperature indicate an age of 23,600. The result is consistent with 14C and 230Th dating of calcrete found coating the bones. ?? 1979.

  9. Considerations on Temperature, Longevity and Aging

    PubMed Central

    Conti, Bruno

    2008-01-01

    A modest reduction in body temperature prolongs longevity and possibly retards aging in both poikilotherm and homeotherm animals. Some of the possible mechanisms mediating these effects are considered here with respect to major aging models and theories. PMID:18425417

  10. Temperature, Humidity, And Polymer Aging

    NASA Technical Reports Server (NTRS)

    Cuddihy, Edward F.

    1988-01-01

    Report presents analysis of experimental data on electrical resistivity of polymer (polyvinyl butyral) as function of temperature and relative humidity. Resulting theoretical expression for electrical resistivity resembles generally accepted empirical law for the corrosion rate.

  11. Invited review: aging and human temperature regulation.

    PubMed

    Kenney, W Larry; Munce, Thayne A

    2003-12-01

    This mini-review focuses on the effects of aging on human temperature regulation. Although comprehensive reviews have been published on this topic (Kenney WL. Exercise and Sport Sciences Reviews, Baltimore: Williams & Wilkins, 1997, p. 41-76; Pandolf KB. Exp Aging Res 17: 189-204, 1991; Van Someren EJ, Raymann RJ, Scherder EJ, Daanen HA, and Swaab DF. Ageing Res Rev 1: 721-778, 2002; and Young AJ. Exp Aging Res 17: 205-213, 1991), this mini-review concisely summarizes the present state of knowledge about human temperature regulation and aging in thermoneutral conditions, as well as during hypo- and hyperthermic challenges. First, we discuss age-related effects on baseline body core temperature and phasing rhythms of the circadian temperature cycle. We then examine the altered physiological responses to cold stress that result from aging, including attenuated peripheral vasoconstriction and reduced cold-induced metabolic heat production. Finally, we present the age-related changes in sweating and cardiovascular function associated with heat stress. Although epidemiological evidence of increased mortality among older adults from hypo- and hyperthermia exists, this outcome does not reflect an inability to thermoregulate with advanced age. In fact, studies that have attempted to separate the effects of chronological age from concurrent factors, such as fitness level, body composition, and the effects of chronic disease, have shown that thermal tolerance appears to be minimally compromised by age. PMID:14600165

  12. Shallow burial dolomitisation of Middle-Upper Permian paleosols in an extensional tectonic context (SE Iberian Basin, Spain): Controls on temperature of precipitation and source of fluids

    NASA Astrophysics Data System (ADS)

    Benito, M. Isabel; De la Horra, Raúl; López-Gómez, José; Barrenechea, José F.; Luque, Javier; Arche, Alfredo

    2011-06-01

    This work is focused on carbonate paleosols developed in three stratigraphic sections (Landete, Talayuelas and Henarejos) of the Middle-Late Permian Alcotas Formation in the SE Iberian Basin. The Alcotas Formation, of alluvial origin, was deposited in semi-connected half-grabens developed during the early stages of the Permian-Triassic rifting stage that affected the Iberian Basin. The studied sections were located in two of these half-grabens, the Henarejos section being much closer to the basin boundary fault than the other two sections. The mineralogy and texture of the carbonate precursor of paleosols in the three studied sections are not preserved because original carbonate is replaced by coarse crystals of dolomite and/or magnesite. Dolomite crystals are typically euhedral, displaying rhombohedral shapes and reddish luminescence, although in the Henarejos section dolomite displays non-planar boundaries and frequently saddle habit. Micas are deformed and adapted to dolomite crystals, which, in turn, are affected by stylolites, suggesting that dolomite precipitated before mechanical and chemical compaction. Carbon and oxygen isotopic compositions of dolomite from the three sections show different values (δ 13C VPDB mean values = - 6.7‰, - 5.5‰ and - 7.5‰; δ 18O VPDB mean values = - 4.0‰; -5.6‰ and - 8.2‰, at Landete, Talayuelas and Henarejos sections, respectively). The 87Sr/ 86Sr ratios are similar in the three sections yielding values between 0.71391 and 0.72213. The petrographic and geochemical features of dolomite in the three studied sections suggest precipitation from similar fluids and during shallow burial diagenesis. Assuming that the minimum temperature for dolomite precipitation in the Henarejos section was 60 °C (as suggested by the presence of non-planar saddle habit), and that the dolomitizing fluid had similar δ 18O values at the three localities, then dolomite in the Talayuelas and Landete sections precipitated at temperatures

  13. Low-temperature formation of pyrrhotite from magnetite sup + pyrite: Evidence from low-grade metamorphism and implications for magnetite preservation during deep burial

    SciTech Connect

    Gillett, S.L. )

    1991-03-01

    Early magnetite in sedimentary rocks must be preserved to retain a paleomagnetic signature; however, reactions such as Fe{sub 3}O{sub 4} + 3 FeS{sub 2} + CH{sub 4}' = (organic matter) = 6 FeS' (pyrr.) + CO{sub 2} + 2 H{sub 2}O tend to the right for temperatures less than {approximately}200C. Such low temperatures strongly imply that magnetite can be destroyed merely by deep burial. Such pyrrhotite formation is illustrated by very low-grade metamorphism in a contact aureole surrounding the Jurassic Notch Peak stock in the central House Range of western Utah. The stock invades a Cambrian sedimentary sequence containing miogeoclinal limestones with intercalated siltstones. Limestones in the aureole yield a scattered, two-polarity remagnetization, residing in pyrrhotite, which extends into rocks that appear unmetamorphosed (temperatures {approximately}250C). The pyrrhotite could not have been precipitated from externally derived fluids because oxygen isotopic data from the limestones show no influence of magmatic or phreatic water; hence, it must have formed in situ, as in the above equation. Outside the aureole, a characteristic magnetization is preserved that apparently reflects late Paleozoic remagnetization and that probably resides in authigenic magnetite. Hence, it appears that this relatively late magnetite was in turn destroyed by modest reheating from the pluton. In general, thermal remagnetization of sedimentary rocks is probably rare: chemical changes probably have a much more profound effect on the paleomagnetic signatures.

  14. Alternations in burial and exhumation along the Selimiye (Kayabükü) shear zone in the Menderes Massif from detailed garnet pressure-temperature paths

    NASA Astrophysics Data System (ADS)

    Kelly, E. D.; Atakturk, K. R.; Catlos, E. J.; Lizzadro-McPherson, D. J.; Cemen, I.; Lovera, O. M.

    2015-12-01

    Pressure-temperature (P-T) paths derived from garnet chemical zoning and supported by thermal modeling record alternating burial and exhumation during Main Menderes Metamorphism in western Turkey. We studied six rocks along the Selimiye (Kayabükü) shear zone, three from the footwall (Çine nappe) and three from the hanging wall (Selimiye nappe). The shear zone bounds the southern Menderes Massif metamorphic core complex and has been suggested to record compression followed by extension. The rocks are lower-amphibolite facies garnet-bearing metapelites with nearly identical mineral suites. Retrograde overprinting hinders classical thermobarometry; to overcome this, preserved chemical zoning in garnet combined with a G-minimization approach was used to construct detailed P-T paths (e.g., 50 points in some paths). During continuous temperature increase, the Çine nappe paths show increasing, decreasing, and then increasing pressure (an N-shaped path) ending at 7-8 kbar and ~565-590 °C. The Selimiye nappe paths show a single increase in P-T ending at ~7.3 kbar and ~580 °C. Similar bulk-rock compositions in all samples and the separation by the shear zone suggest that garnets grew during distinct events in each nappe. The timing of garnet growth, and thus the P-T paths, is currently undetermined, as monazite inclusions in garnet appear secondary and complicated by excess common Pb. The Çine nappe N-shaped path describes alternations in burial and exhumation, possibly due to thrust motion along the shear zone. To demonstrate the physical plausibility of the P-T paths, a 2-D finite difference solution to the diffusion-advection equation was applied. The results of the thermal modeling suggest that thrusting, denudation, and renewed thrusting would produce similar changes in P-T to the N-shaped path. Thus, the Çine nappe N-shaped P-T path appears to record a gap in thrust motion along the Selimiye (Kayabükü) shear zone prior to ultimate unroofing of the massif.

  15. Numerical simulations of complex temperature, burial, and erosion histories for sedimentary basins and their calibration: Examples from western Germany

    SciTech Connect

    Buker, C.; Littke, R.; Welte, D.H.

    1995-08-01

    The detailed and reliable reconstruction of the geological and thermal evolution of sedimentary basins forms the indispensable basis of any simulation of generation, migration and accumulation of hydrocarbons. For this purpose - although often not taken into account - analysing and quantifying the uplift and erosion history is as important as the subsidence and temperature history. The reconstruction of the timing of hydrocarbon generation, petroleum expulsion and migration and the changing reservoir characteristics is only possible based on such an integrated approach. Applying this technique on the Carboniferous Ruhr Basin and the Lower Saxony Basin (western Germany) by utilising 1-D and 2-D forward modeling approaches resulted in important and new quantitative information on their temperature, subsidence and erosion histories which are of fundamental geological interest. The basin evolution models were calibrated using vitrinite reflectance data, fluid inclusion temperatures, and apatite and zircon fission track data. The detailed knowledge of the geological and thermal basin evolution then allowed in combination with a new kinetic model for gas generation from coals the modeling of generation, migration and accumulation of methane from Carboniferous coal seams.

  16. Difference of brightness temperatures between 19.35 GHz and 37.0 GHz in CHANG'E-1 MRM: implications for the burial of shallow bedrock at lunar low latitude

    NASA Astrophysics Data System (ADS)

    Yu, Wen; Li, Xiongyao; Wei, Guangfei; Wang, Shijie

    2016-03-01

    Indications of buried lunar bedrock may help us to understand the tectonic evolution of the Moon and provide some clues for formation of lunar regolith. So far, the information on distribution and burial depth of lunar bedrock is far from sufficient. Due to good penetration ability, microwave radiation can be a potential tool to ameliorate this problem. Here, a novel method to estimate the burial depth of lunar bedrock is presented using microwave data from Chang'E-1 (CE-1) lunar satellite. The method is based on the spatial variation of differences in brightness temperatures between 19.35 GHz and 37.0 GHz (ΔTB). Large differences are found in some regions, such as the southwest edge of Oceanus Procellarum, the area between Mare Tranquillitatis and Mare Nectaris, and the highland east of Mare Smythii. Interestingly, a large change of elevation is found in the corresponding region, which might imply a shallow burial depth of lunar bedrock. To verify this deduction, a theoretical model is derived to calculate the ΔTB. Results show that ΔTB varies from 12.7 K to 15 K when the burial depth of bedrock changes from 1 m to 0.5 m in the equatorial region. Based on the available data at low lunar latitude (30°N-30°S), it is thus inferred that the southwest edge of Oceanus Procellarum, the area between Mare Tranquillitatis and Mare Nectaris, the highland located east of Mare Smythii, the edge of Pasteur and Chaplygin are the areas with shallow bedrock, the burial depth is estimated between 0.5 m and 1 m.

  17. Passive absolute age and temperature history sensor

    SciTech Connect

    Robinson, Alex; Vianco, Paul T.

    2015-11-10

    A passive sensor for historic age and temperature sensing, including a first member formed of a first material, the first material being either a metal or a semiconductor material and a second member formed of a second material, the second material being either a metal or a semiconductor material. A surface of the second member is in contact with a surface of the first member such that, over time, the second material of the second member diffuses into the first material of the first member. The rate of diffusion for the second material to diffuse into the first material depends on a temperature of the passive sensor. One of the electrical conductance, the electrical capacitance, the electrical inductance, the optical transmission, the optical reflectance, or the crystalline structure of the passive sensor depends on the amount of the second material that has diffused into the first member.

  18. Relationship of clay-mineral diagenesis to temperature, age, and hydrocarbon generation–an example from the Anadarko Basin, Oklahoma

    USGS Publications Warehouse

    Pollastro, Richard M.; Schmoker, James W.

    1989-01-01

    Randomly interstratified illite/smectite (I/S) is present in Springeran and Morrowan rocks (Late Mississippian and Early Pennsylvanian) of the Anadarko basin, Oklahoma, at present-day depths <2,750 m, but disappears at depths of 2,750-3,050 m. Only ordered I/S is found in samples below 3,050 m. The work reported here relates the diagenesis of I/S to burial history and oil generation in the Anadarko basin and tests the dependence of the smectite-to-illite reaction on temperature and time. Published temperature models of clay diagenesis suggest that, for Tertiary and Cretaceous rocks, the transition from randomly interstratified I/S to ordered I/S occurs at 100-110°C. Burial reconstructions for the Anadarko basin indicate that maximum temperatures of 100-110°C correspond to present-day burial depths between 2,700 and 3,100 m. These independently calculated depths for the 100-110°C isotherm match the depths at which randomly interstratified I/S is observed to disappear in Morrowan-Springeran rocks. Thus, random I/S disappears at the same temperature in rocks that differ in age by some 300 m.y. Although the extent of the smectite-to-illite reaction is controlled by kinetics, and effects of time are apparent in laboratory experiments and short-lived geologic systems, the results of this study suggest that time plays a secondary role in long-term diagenetic settings.

  19. Large increases in carbon burial in northern lakes during the Anthropocene.

    PubMed

    Heathcote, Adam J; Anderson, N John; Prairie, Yves T; Engstrom, Daniel R; del Giorgio, Paul A

    2015-01-01

    Northern forests are important ecosystems for carbon (C) cycling and lakes within them process and bury large amounts of organic-C. Current burial estimates are poorly constrained and may discount other shifts in organic-C burial driven by global change. Here we analyse a suite of northern lakes to determine trends in organic-C burial throughout the Anthropocene. We found burial rates increased significantly over the last century and are up to five times greater than previous estimates. Despite a correlation with temperature, warming alone did not explain the increase in burial, suggesting the importance of other drivers including atmospherically deposited reactive nitrogen. Upscaling mean lake burial rates for each time period to global northern forests yields up to 4.5 Pg C accumulated in the last 100 years--20% of the total burial over the Holocene. Our results indicate that lakes will become increasingly important for C burial under future global change scenarios. PMID:26607672

  20. Large increases in carbon burial in northern lakes during the Anthropocene

    NASA Astrophysics Data System (ADS)

    Heathcote, Adam J.; Anderson, N. John; Prairie, Yves T.; Engstrom, Daniel R.; Del Giorgio, Paul A.

    2015-11-01

    Northern forests are important ecosystems for carbon (C) cycling and lakes within them process and bury large amounts of organic-C. Current burial estimates are poorly constrained and may discount other shifts in organic-C burial driven by global change. Here we analyse a suite of northern lakes to determine trends in organic-C burial throughout the Anthropocene. We found burial rates increased significantly over the last century and are up to five times greater than previous estimates. Despite a correlation with temperature, warming alone did not explain the increase in burial, suggesting the importance of other drivers including atmospherically deposited reactive nitrogen. Upscaling mean lake burial rates for each time period to global northern forests yields up to 4.5 Pg C accumulated in the last 100 years--20% of the total burial over the Holocene. Our results indicate that lakes will become increasingly important for C burial under future global change scenarios.

  1. Large increases in carbon burial in northern lakes during the Anthropocene

    PubMed Central

    Heathcote, Adam J.; Anderson, N. John; Prairie, Yves T.; Engstrom, Daniel R.; del Giorgio, Paul A.

    2015-01-01

    Northern forests are important ecosystems for carbon (C) cycling and lakes within them process and bury large amounts of organic-C. Current burial estimates are poorly constrained and may discount other shifts in organic-C burial driven by global change. Here we analyse a suite of northern lakes to determine trends in organic-C burial throughout the Anthropocene. We found burial rates increased significantly over the last century and are up to five times greater than previous estimates. Despite a correlation with temperature, warming alone did not explain the increase in burial, suggesting the importance of other drivers including atmospherically deposited reactive nitrogen. Upscaling mean lake burial rates for each time period to global northern forests yields up to 4.5 Pg C accumulated in the last 100 years—20% of the total burial over the Holocene. Our results indicate that lakes will become increasingly important for C burial under future global change scenarios. PMID:26607672

  2. Paleomagnetic dating of burial diagenesis in Mississippian carbonates, Utah

    NASA Astrophysics Data System (ADS)

    Blumstein, Angela M.; Elmore, R. Douglas; Engel, Michael H.; Elliot, Crawford; Basu, Ankan

    2004-04-01

    The objective of this study is to test models for the origin of widespread secondary magnetizations in the Mississippian Deseret Limestone. The Delle Phosphatic Member of the Deseret Limestone is a source rock for hydrocarbons, and modeling studies indicate that it entered the oil window in the Early Cretaceous during the Sevier orogeny. Paleomagnetic and rock magnetic results from the Deseret Limestone and the stratigraphically equivalent Chainman Shale in central and western Utah indicate that the units contain two ancient magnetizations residing in magnetite. Burial temperatures are too low for the magnetizations to be thermoviscous in origin, and they are interpreted to be chemical remanent magnetizations (CRMs). Fold tests from western Utah indicate the presence of a prefolding Triassic to Jurassic CRM. Geochemical (87Sr/86Sr, δ13C, and δ18O) and petrographic analyses suggest that externally derived fluids did not alter these rocks. This CRM was acquired at the beginning of the oil window and is interpreted to be the result of burial diagenesis of organic matter. A second younger CRM in western central Utah is apparently postfolding and is probably Late Cretaceous to early Tertiary in age. On the basis of the thermal modeling, the timing overlaps with the oil window. These results are consistent with a connection between organic matter maturation and remagnetization. Modeling of the smectite-to-illite transformation in the Deseret Limestone suggests a mean age prior to acquisition of both CRMs, although the range for illitization overlaps with the Triassic to Jurassic CRM. The results of this study support the hypothesis that pervasive CRMs can be related to burial diagenetic processes. In addition, paleomagnetism can be used to determine the timing of such processes, which can benefit hydrocarbon exploration efforts.

  3. Burial Ground Expansion Hydrogeologic Characterization

    SciTech Connect

    Gaughan , T.F.

    1999-02-26

    Sirrine Environmental Consultants provided technical oversight of the installation of eighteen groundwater monitoring wells and six exploratory borings around the location of the Burial Ground Expansion.

  4. Age specific fecundity of Lygus hesperus in high, fluctuating temperatures.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have simulated hourly temperatures to examine Lygus response to hot summers in the San Joaquin Valley. Constant temperature of 33C quickly killed Lygus and SJV temperatures routinely surpass this level. Average hourly temperatures were tested for the months May, July, and September. Age specific ...

  5. 78 FR 76574 - Burial Benefits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-18

    ... rewrite in plain language its regulations that govern entitlement to monetary burial benefits, which... published in the Federal Register on April 8, 2008 (73 FR 19,021), VA proposed to reorganize and rewrite in plain language provisions applicable to burial benefits. This proposed rule would build upon...

  6. Indien Personhood III: Water Burial

    ERIC Educational Resources Information Center

    Miller, Jay

    2005-01-01

    Water burial is a way to return a body to its key primal element. It revives and transforms both the soul and the person. Sometimes water burial leads to a new life floating in a womb. Sometimes it disperses to provide a moist and nutrient-rich medium for a vast variety of other lives, making a contribution to the much larger whole. In this…

  7. Parallel circuits control temperature preference in Drosophila during ageing

    PubMed Central

    Shih, Hsiang-Wen; Wu, Chia-Lin; Chang, Sue-Wei; Liu, Tsung-Ho; Sih-Yu Lai, Jason; Fu, Tsai-Feng; Fu, Chien-Chung; Chiang, Ann-Shyn

    2015-01-01

    The detection of environmental temperature and regulation of body temperature are integral determinants of behaviour for all animals. These functions become less efficient in aged animals, particularly during exposure to cold environments, yet the cellular and molecular mechanisms are not well understood. Here, we identify an age-related change in the temperature preference of adult fruit flies that results from a shift in the relative contributions of two parallel mushroom body (MB) circuits—the β′- and β-systems. The β′-circuit primarily controls cold avoidance through dopamine signalling in young flies, whereas the β-circuit increasingly contributes to cold avoidance as adult flies age. Elevating dopamine levels in β′-afferent neurons of aged flies restores cold sensitivity, suggesting that the alteration of cold avoidance behaviour with ageing is functionally reversible. These results provide a framework for investigating how molecules and individual neural circuits modulate homeostatic alterations during the course of senescence. PMID:26178754

  8. Parallel circuits control temperature preference in Drosophila during ageing.

    PubMed

    Shih, Hsiang-Wen; Wu, Chia-Lin; Chang, Sue-Wei; Liu, Tsung-Ho; Lai, Jason Sih-Yu; Fu, Tsai-Feng; Fu, Chien-Chung; Chiang, Ann-Shyn

    2015-01-01

    The detection of environmental temperature and regulation of body temperature are integral determinants of behaviour for all animals. These functions become less efficient in aged animals, particularly during exposure to cold environments, yet the cellular and molecular mechanisms are not well understood. Here, we identify an age-related change in the temperature preference of adult fruit flies that results from a shift in the relative contributions of two parallel mushroom body (MB) circuits—the β'- and β-systems. The β'-circuit primarily controls cold avoidance through dopamine signalling in young flies, whereas the β-circuit increasingly contributes to cold avoidance as adult flies age. Elevating dopamine levels in β'-afferent neurons of aged flies restores cold sensitivity, suggesting that the alteration of cold avoidance behaviour with ageing is functionally reversible. These results provide a framework for investigating how molecules and individual neural circuits modulate homeostatic alterations during the course of senescence. PMID:26178754

  9. Being cool: how body temperature influences ageing and longevity.

    PubMed

    Keil, Gerald; Cummings, Elizabeth; de Magalhães, João Pedro

    2015-08-01

    Temperature is a basic and essential property of any physical system, including living systems. Even modest variations in temperature can have profound effects on organisms, and it has long been thought that as metabolism increases at higher temperatures so should rates of ageing. Here, we review the literature on how temperature affects longevity, ageing and life history traits. From poikilotherms to homeotherms, there is a clear trend for lower temperature being associated with longer lifespans both in wild populations and in laboratory conditions. Many life-extending manipulations in rodents, such as caloric restriction, also decrease core body temperature. Nonetheless, an inverse relationship between temperature and lifespan can be obscured or reversed, especially when the range of body temperatures is small as in homeotherms. An example is observed in humans: women appear to have a slightly higher body temperature and yet live longer than men. The mechanisms involved in the relationship between temperature and longevity also appear to be less direct than once thought with neuroendocrine processes possibly mediating complex physiological responses to temperature changes. Lastly, we discuss species differences in longevity in mammals and how this relates to body temperature and argue that the low temperature of the long-lived naked mole-rat possibly contributes to its exceptional longevity. PMID:25832892

  10. Low-Temperature Aging Mechanisms in U-6wt% Nb

    SciTech Connect

    Hsiung, L L

    2004-12-07

    Phase stability and aging mechanisms in a water-quenched (WQ) U-6wt% Nb (U-14at% Nb) alloy artificially aged at 200 C and naturally aged at ambient temperature for 15 years have been investigated and studied using Vickers-hardness measurement, X-ray diffraction (XRD) analysis, and transmission electron microscopy (TEM) techniques. Age hardening/softening phenomenon is recorded from the artificially aged samples based upon the microhardness measurement. The age hardening can be readily rationalized by the occurrence of fine-scaled Nb segregation, or spinodal decomposition, within the {alpha}'' domains, which results in the formation of a modulated structure containing nano-scaled Nb-rich and Nb-lean domains. Prolonged aging leads to age softening of the alloy by coarsening of the modulated structure. Chemical ordering, or disorder-order phase transformation, is found within the naturally aged alloy according to TEM observations of antiphase domain boundaries (APBs) and superlattice diffraction patterns. A possible superlattice structure for the ordered {alpha}'' phase observed in the naturally aged sample and underlying low-temperature aging mechanisms are proposed.

  11. TEMPERATURE AND MOISTURE CONTROL OF SEED AGING IN RYE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The interactions between temperature and moisture that regulate seed aging were measured using rye seeds. Experiments include a number of long term storage studies under conditions of varying relative humidity (RH), water content and temperature. Decrease in germination percentage and radicle leng...

  12. Ageing under Shear: Effect of Stress and Temperature Field

    NASA Astrophysics Data System (ADS)

    Shukla, Asheesh; Joshi, Yogesh M.

    2008-07-01

    In this work we studied the effect of oscillatory stress and temperature on the ageing dynamics of aqueous suspension of laponite. At the higher magnitude of stress, elastic and viscous moduli of the system underwent a sharp rise with the ageing time. The age at the onset of rise and the sharpness of the same increased with the magnitude of stress. We propose that at the beginning of ageing, the strain associated with the oscillatory stress field affects the lower modes in the relaxation time distribution. The higher modes, which are not significantly affected by the deformation field, continue to grow increasing the viscosity of the system thereby lowering the magnitude of the deformation field. Progressive decrease in the later reduces the range of relaxation modes affected by it. This dynamics eventually leads to an auto-catalytic increase in the elastic and viscous moduli. An increase in temperature accelerates the ageing process by shifting the ageing dynamics to a lower ageing time. This is due the microscopic relaxation dynamics, which causes ageing, becomes faster with increase in the temperature.

  13. Organic carbon burial efficiency in a large tropical hydroelectric reservoir

    NASA Astrophysics Data System (ADS)

    Mendonça, Raquel; Sobek, Sebastian; Kosten, Sarian; Cole, Jonathan; Cardoso, Simone; Roland, Fábio

    2014-05-01

    temperature. Among hydroelectric reservoirs, OC burial efficiency will probably be higher in more eutrophic and in colder systems and lower in warm systems receiving relatively low terrestrial OC inputs.

  14. Dating Pliocene lacustrine sediments in the central Jordan Valley, Israel — Implications for cosmogenic burial dating

    NASA Astrophysics Data System (ADS)

    Davis, M.; Matmon, A.; Fink, D.; Ron, H.; Niedermann, S.

    2011-05-01

    Cosmogenic burial dating of sediments is usually used at sites with relatively simple or known exposure-burial histories, such as in caves. In an attempt to extend the applicability of the method to other common geological settings (i.e. the dating of late Neogene sedimentary formations), where much less is known about the exposure-burial history, we apply the cosmogenic burial method on Pliocene-early Pleistocene (1.5-4.5 Ma) lacustrine sediments in the central Jordan Valley, Israel. 26Al, 10Be, and 21Ne concentrations in quartz were obtained from a 170 m tectonically-tilted section. Assuming fast burial and no post-burial production we obtained burial ages which range between 3.5 and 5.3 Ma. Integrating simple geological reasoning and the cosmogenic nuclide data, post burial production is found to be insignificant. We also found that the samples contain two distinct populations of grains (chert and quartz) from two different sources which experienced different pre-burial exposure histories. The cosmogenic nuclide concentrations in the samples are in accordance with those expected for the mixing of two sources, and the burial ages computed for both end members agree. Theoretical calculations of two-source mixing show that initial 26Al/10Be ratios are depressed relative to the expected surface ratios and may result in burial ages overestimated by as much as 500 ka. Using ages derived from cosmogenic nuclides, independent age constraints, and magnetostratigraphy we correlate the bottom of the section to the Cochiti Normal magnetic subchron (4.19-4.30 Ma) within the Reverse Gilbert chron, and the top of the section to the Reverse subchron at the top of the Gilbert chron (3.60-4.19 Ma).

  15. Investigation of temperature dependence of development and aging

    NASA Technical Reports Server (NTRS)

    Sacher, G. A.

    1969-01-01

    Temperature dependence of maturation and metabolic rates in insects, and the failure of vital processes during development were investigated. The paper presented advances the general hypothesis that aging in biological systems is a consequence of the production of entropy concomitant with metabolic activity.

  16. Modeling sugarcane growth in response to age, insolation, and temperature

    SciTech Connect

    How, K.T.S.

    1986-01-01

    Modeling sugarcane growth in response to age of cane, insolation and air temperature using first-order multiple regression analysis and a nonlinear approach is investigated. Data are restricted to one variety from irrigated fields to eliminate the impact of varietal response and rainfall. Ten first-order models are investigated. The predictant is cane yield from 600 field tests. The predictors are cumulative values of insolation, maximum temperature, and minimum temperature for 3, 6, 12, and 18 months, or for each crop period derived from weather observations near the test plots. The low R-square values indicate that the selected predictor variables could not account for a substantial proportion of the variations of cane yield and the models have limited predictive values. The nonlinear model is based on known functional relationships between growth and age, growth and insolation, and growth and maximum temperature. A mathematical expression that integrates the effect of age, insolation and maximum temperature is developed. The constant terms and coefficients of the equation are determined from the requirement that the model must produce results that are reasonable when compared with observed monthly elongation data. The nonlinear model is validated and tested using another set of data.

  17. Heart Rates in Hospitalized Children by Age and Body Temperature

    PubMed Central

    Bonafide, Christopher P.; Brady, Patrick W.

    2015-01-01

    BACKGROUND AND OBJECTIVES: Heart rate (HR) is frequently used by clinicians in the hospital to assess a patient’s severity of illness and make treatment decisions. We sought to develop percentiles that characterize the relationship of expected HR by age and body temperature in hospitalized children and to compare these percentiles with published references in both primary care and emergency department (ED) settings. METHODS: Vital sign data were extracted from electronic health records of inpatients <18 years of age at 2 large freestanding children’s hospitals from July 2011 to June 2012. We selected up to 10 HR-temperature measurement pairs from each admission. Measurements from 60% of patients were used to derive the percentile curves, with the remainder used for validation. We compared our upper percentiles with published references in primary care and ED settings. RESULTS: We used 60 863 observations to derive the percentiles. Overall, an increase in body temperature of 1°C was associated with an increase of ∼10 beats per minute in HR, although there were variations across age and temperature ranges. For infants and young children, our upper percentiles were lower than in primary care and ED settings. For school-age children, our upper percentiles were higher. CONCLUSIONS: We characterized expected HR by age and body temperature in hospitalized children. These percentiles differed from references in primary care and ED settings. Additional research is needed to evaluate the performance of these percentiles for the identification of children who would benefit from further evaluation or intervention for tachycardia. PMID:25917984

  18. Carbon dioxide and organic acids: origin and role in burial diagenesis (Texas Gulf Coast Tertiary)

    SciTech Connect

    Lundegard, P.D.

    1985-01-01

    Carbon dioxide produced by decarboxylation of organic matter is not a dominant factor in secondary porosity development. Material balance calculations indicate the amount of feldspar and carbonate dissolution that has taken place in Tertiary sandstones of the Texas Gulf Coast far exceeds that which is explainable by decarboxylation. Other potential sources of acid for dissolution reactions include reverse weathering reactions in shales, an hydrous pyrolysis reactions between organic carbon and oxygen in H/sub 2/O to yield CO/sub 2/ or organic acids. Considerations of CO/sub 2/ solubility and the temperature distribution of organic acids imply that these species must be generated locally to cause significant dissolution. The CO/sub 2/ content of gas from Gulf Coast Tertiary sandstones is proportional to reservoir age, and increases with depth and temperature at a rate that is approximately exponential. In the Wilcox Formation the increase in CO/sub 2/ content continues beyond depths where dissolved organic acids are abundant and where kerogen has lost its oxygen from functional groups that are readily liberated as CO/sub 2/. In this formation the /sup 13/C of CO/sub 2/ and CH/sub 4/ are proportional to temperature and to each other. Either mixing with fluids derived from the Mesozoic carbonate section of deep CO/sub 2/ generation by kinetically controlled organic reactions may explain these data. Organic acid concentration with depth and temperature indicates a non-biological origin by thermal cracking of kerogen during burial. Continued burial leads to their thermal decomposition. Cessation of burial may lead to meteoric water invasion and organic acid destruction by biological processes. The effect of time on organic acid production is minor compared to temperature.

  19. The aging correlation (RH + t): Relative humidity (%) + temperature (deg C)

    NASA Technical Reports Server (NTRS)

    Cuddihy, E. F.

    1986-01-01

    An aging correlation between corrosion lifetime, and relative humidity RH (%) and temperature t (C) has been reported in the literature. This aging correlation is a semi-log plot of corrosion lifetime on the log scale versus the interesting summation term RH(%) + t(C) on the linear scale. This empirical correlation was derived from observation of experimental data trends and has been referred to as an experimental law. Using electrical resistivity data of polyvinyl butyral (PVB) measured as a function of relative humidity and temperature, it was found that the electrical resistivity could be expressed as a function of the term RH(%) t(C). Thus, if corrosion is related to leakage current through an organic insulator, which, in turn, is a function of RH and t, then some partial theoretical validity for the correlation is indicated. This article describes the derivation of the term RH(%) t(C) from PVB electrical resistivity data.

  20. Effects of Age on Temperature Responses During Exposure to Hypergravity

    NASA Technical Reports Server (NTRS)

    Fung, C.K.; Baer, L. A.; Moran, M. M.; Wang, T. J.; Yuan, F.; Daunton, N. G.; Corcoran, M. L.; Wade, C. E.; Dalfan, Bonnie P. (Technical Monitor)

    2001-01-01

    Rats subjected to centrifugation show a marked decrease in body temperature relating to gravity level. Several studies have indicated, that an initial response to centrifugation is followed by acclimation. To test for differences between young (Y; 2 months) and mature (M; 8 months) rats in their response in temperature, both groups were exposed to hypergravity induced by centrifugation. Thirty-six male rats were divided into four groups according to age and G-load (control (1.0G-Y and 1.0G-M), 2.0G-Y or 2.0G-M) and were housed in pairs in standard vivarium cages. During the 7-day period of centrifugation, temperature was measured every five minutes by surgically implanted telemeters. Body mass was measured daily. We found that initial body temperature in 2.0G-M was less than that of 2.0G-Y. Both hypergravity groups (2.0G-Y and 2.0G-M) showed a decrease in temperature at the onset of centrifugation, and the change in temperature (Delta = 0.5 C) remained the same between the groups. Significant differences persisted with 2.0G-Y recovering to control values in four days and 2.0G-M recovering in five days. These results indicate that the mature animals have a similar response as the younger animals, but take longer to acclimate.

  1. Effect of Temperature on the Aging rate of Li Ion Battery Operating above Room Temperature

    NASA Astrophysics Data System (ADS)

    Leng, Feng; Tan, Cher Ming; Pecht, Michael

    2015-08-01

    Temperature is known to have a significant impact on the performance, safety, and cycle lifetime of lithium-ion batteries (LiB). However, the comprehensive effects of temperature on the cyclic aging rate of LiB have yet to be found. We use an electrochemistry-based model (ECBE) here to measure the effects on the aging behavior of cycled LiB operating within the temperature range of 25 °C to 55 °C. The increasing degradation rate of the maximum charge storage of LiB during cycling at elevated temperature is found to relate mainly to the degradations at the electrodes, and that the degradation of LCO cathode is larger than graphite anode at elevated temperature. In particular, the formation and modification of the surface films on the electrodes as well as structural/phase changes of the LCO electrode, as reported in the literatures, are found to be the main contributors to the increasing degradation rate of the maximum charge storage of LiB with temperature for the specific operating temperature range. Larger increases in the Warburg elements and cell impedance are also found with cycling at higher temperature, but they do not seriously affect the state of health (SoH) of LiB as shown in this work.

  2. Effect of Temperature on the Aging rate of Li Ion Battery Operating above Room Temperature

    PubMed Central

    Leng, Feng; Tan, Cher Ming; Pecht, Michael

    2015-01-01

    Temperature is known to have a significant impact on the performance, safety, and cycle lifetime of lithium-ion batteries (LiB). However, the comprehensive effects of temperature on the cyclic aging rate of LiB have yet to be found. We use an electrochemistry-based model (ECBE) here to measure the effects on the aging behavior of cycled LiB operating within the temperature range of 25 °C to 55 °C. The increasing degradation rate of the maximum charge storage of LiB during cycling at elevated temperature is found to relate mainly to the degradations at the electrodes, and that the degradation of LCO cathode is larger than graphite anode at elevated temperature. In particular, the formation and modification of the surface films on the electrodes as well as structural/phase changes of the LCO electrode, as reported in the literatures, are found to be the main contributors to the increasing degradation rate of the maximum charge storage of LiB with temperature for the specific operating temperature range. Larger increases in the Warburg elements and cell impedance are also found with cycling at higher temperature, but they do not seriously affect the state of health (SoH) of LiB as shown in this work. PMID:26245922

  3. Interface degradation in CAS/Nicalon during elevated temperature aging

    SciTech Connect

    Plucknett, K.P.; Cain, R.L.; Lewis, M.H.

    1995-03-01

    A CaO-Al{sub 2}O{sub 3}-SiO{sub 2} (CAS)/Nicalon glass-ceramic matrix composite has been subjected to elevated temperature oxidation heat-treatments between 375 and 1200{degrees}C, for up to 100 hours. Micro- and macro-mechanical properties have been determined by fiber push-down, using a mechanical properties microprobe, and flexure testing, respectively. Aging between 450 and 800{degrees}C results in significant property degradation, with reduced bending modulus and flexure strength, increased fiber sliding stress, and a transition to a purely brittle failure mode. Aging degradation is due to oxidative removal of the carbon interlayer, with the subsequent formation of a silica bond between fiber and matrix. At higher temperatures, carbon is retained due to the formation of a protective silica plug at exposed fiber ends, with the subsequent retention of composite properties. Short duration pre-treatment schedules, at 1000 or 1100{degrees}C, were developed to prevent intermediate temperature property degradation.

  4. Incision of the Yangtze River at the First Bend Determined by Three-Nuclide Burial Dating

    NASA Astrophysics Data System (ADS)

    McPhillips, D. F.; Hoke, G. D.; Rood, D. H.; Bierman, P. R.

    2015-12-01

    On the southeast margin of the Tibetan Plateau, the evolution of the Yangtze River and its major tributaries has become an important source of data for investigating geodynamics. In particular, the timing of river incision is frequently interpreted as a proxy for the timing of surface uplift in the absence of structural evidence. We investigate the timing of the incision of the gorge at the First Bend using cosmogenic nuclide burial dating of coarse, quartz sediments from caves. Sediments were deposited when the caves were near river level and subsequently abandoned as the river incised. To resolve burial ages >5 Ma, we measured the radionuclides 10Be and 26Al, and the stable nuclide 21Ne. Results from 4 caves show that 26Al and 10Be concentrations are an order of magnitude lower in abandoned cave samples than in a river-level cave sample where deposition is active (10Be: 1.3x104 and 3.4x105 at/g). In contrast, 26Al/10Be ratios in all caves are ≥6.2 and indistinguishable within error. 21Ne concentrations range from 2.1x106 to 7.8x106 at/g. The results are consistent with an old age for the abandoned cave deposits, such that most of the radionuclides initially present have decayed and the concentrations that we measure today are the result of millions of years of exposure to muons. We solve for burial ages, taking into account in situ muogenic production, and find that the majority of the gorge (1 km) was likely incised between ~12 and 9 Ma. The results also require that the rate of river incision declined after the gorge was cut below the lowest elevation cave at 9 Ma. Inverse modeling of published low-temperature thermochronology (Ouimet et al., 2010) supports our burial age results. River capture near the First Bend, which likely integrated the modern Yangtze, likely occurred prior to the mid-Miocene incision of the gorge. In view of the geographic position of the First Bend—just downslope from the southeast margin of the Plateau—it is difficult to explain

  5. Carbon sequestration via wood burial

    PubMed Central

    Zeng, Ning

    2008-01-01

    To mitigate global climate change, a portfolio of strategies will be needed to keep the atmospheric CO2 concentration below a dangerous level. Here a carbon sequestration strategy is proposed in which certain dead or live trees are harvested via collection or selective cutting, then buried in trenches or stowed away in above-ground shelters. The largely anaerobic condition under a sufficiently thick layer of soil will prevent the decomposition of the buried wood. Because a large flux of CO2 is constantly being assimilated into the world's forests via photosynthesis, cutting off its return pathway to the atmosphere forms an effective carbon sink. It is estimated that a sustainable long-term carbon sequestration potential for wood burial is 10 ± 5 GtC y-1, and currently about 65 GtC is on the world's forest floors in the form of coarse woody debris suitable for burial. The potential is largest in tropical forests (4.2 GtC y-1), followed by temperate (3.7 GtC y-1) and boreal forests (2.1 GtC y-1). Burying wood has other benefits including minimizing CO2 source from deforestation, extending the lifetime of reforestation carbon sink, and reducing fire danger. There are possible environmental impacts such as nutrient lock-up which nevertheless appears manageable, but other concerns and factors will likely set a limit so that only part of the full potential can be realized. Based on data from North American logging industry, the cost for wood burial is estimated to be $14/tCO2($50/tC), lower than the typical cost for power plant CO2 capture with geological storage. The cost for carbon sequestration with wood burial is low because CO2 is removed from the atmosphere by the natural process of photosynthesis at little cost. The technique is low tech, distributed, easy to monitor, safe, and reversible, thus an attractive option for large-scale implementation in a world-wide carbon market. PMID:18173850

  6. Statistical analysis of accelerated temperature aging of semiconductor devices

    NASA Astrophysics Data System (ADS)

    Johnson, W. A.; Milles, M. F.

    1981-05-01

    A number of semiconductor devices taken from a distribution were operated at several elevated temperatures to induce failure in all devices within a reasonable time. Assuming general characteristics of the device failure probability density function (pdf) and its temperature dependence, the expected cumulative failure function (cff) for devices in normal operation were estimated based on statistical inference, taking the average probability of a random device (from the same distribution but operated at a normal temperature) failing as a function of time. A review of the mathematical formalism employed in semiconductor reliability discussions is included. Three failure pdf's at particular usefulness to this analysis--exponential, normal, and lognormal - are discussed. The cff, at times orders of magnitude loss then, at times comparable to the desired system useful, life (*10 to the 4th power to 10 to the 5th power hr) is considered. A review of accelerated temperature aging is presented, and the assumption concerning the general characteristics of the failure pdf, which are fundamental to this analysis, are emphasized.

  7. Ocular Surface Temperature in Age-Related Macular Degeneration

    PubMed Central

    Sodi, Andrea; Giacomelli, Giovanni; Corvi, Andrea; Menchini, Ugo

    2014-01-01

    Background. The aim of this study is to investigate the ocular thermographic profiles in age-related macular degeneration (AMD) eyes and age-matched controls to detect possible hemodynamic abnormalities, which could be involved in the pathogenesis of the disease. Methods. 32 eyes with early AMD, 37 eyes with atrophic AMD, 30 eyes affected by untreated neovascular AMD, and 43 eyes with fibrotic AMD were included. The control group consisted of 44 healthy eyes. Exclusion criteria were represented by any other ocular diseases other than AMD, tear film abnormalities, systemic cardiovascular abnormalities, diabetes mellitus, and a body temperature higher than 37.5°C. A total of 186 eyes without pupil dilation were investigated by infrared thermography (FLIR A320). The ocular surface temperature (OST) of three ocular points was calculated by means of an image processing technique from the infrared images. Two-sample t-test and one-way analysis of variance (ANOVA) test were used for statistical analyses. Results. ANOVA analyses showed no significant differences among AMD groups (P value >0.272). OST in AMD patients was significantly lower than in controls (P > 0.05). Conclusions. Considering the possible relationship between ocular blood flow and OST, these findings might support the central role of ischemia in the pathogenesis of AMD. PMID:25436140

  8. Ocular surface temperature in age-related macular degeneration.

    PubMed

    Sodi, Andrea; Matteoli, Sara; Giacomelli, Giovanni; Finocchio, Lucia; Corvi, Andrea; Menchini, Ugo

    2014-01-01

    Background. The aim of this study is to investigate the ocular thermographic profiles in age-related macular degeneration (AMD) eyes and age-matched controls to detect possible hemodynamic abnormalities, which could be involved in the pathogenesis of the disease. Methods. 32 eyes with early AMD, 37 eyes with atrophic AMD, 30 eyes affected by untreated neovascular AMD, and 43 eyes with fibrotic AMD were included. The control group consisted of 44 healthy eyes. Exclusion criteria were represented by any other ocular diseases other than AMD, tear film abnormalities, systemic cardiovascular abnormalities, diabetes mellitus, and a body temperature higher than 37.5°C. A total of 186 eyes without pupil dilation were investigated by infrared thermography (FLIR A320). The ocular surface temperature (OST) of three ocular points was calculated by means of an image processing technique from the infrared images. Two-sample t-test and one-way analysis of variance (ANOVA) test were used for statistical analyses. Results. ANOVA analyses showed no significant differences among AMD groups (P value >0.272). OST in AMD patients was significantly lower than in controls (P > 0.05). Conclusions. Considering the possible relationship between ocular blood flow and OST, these findings might support the central role of ischemia in the pathogenesis of AMD. PMID:25436140

  9. 38 CFR 3.1703 - Claims for burial benefits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... benefits. 3.1703 Section 3.1703 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Burial Benefits Burial Benefits: General § 3.1703 Claims for burial benefits. Pt. 3, Subpt. B, Nt... after the burial of the veteran. There are no other time limitations to file claims for burial...

  10. 38 CFR 3.1610 - Burial in national cemeteries; burial of unclaimed bodies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... cemeteries; burial of unclaimed bodies. 3.1610 Section 3.1610 Pensions, Bonuses, and Veterans' Relief... unclaimed bodies. The statutory burial allowance and permissible transportation charges as provided in §§ 3... from the officers having jurisdiction over burials in national cemeteries; or (b) Where the body of...

  11. 38 CFR 3.1610 - Burial in national cemeteries; burial of unclaimed bodies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... cemeteries; burial of unclaimed bodies. 3.1610 Section 3.1610 Pensions, Bonuses, and Veterans' Relief... unclaimed bodies. The statutory burial allowance and permissible transportation charges as provided in §§ 3... from the officers having jurisdiction over burials in national cemeteries; or (b) Where the body of...

  12. 38 CFR 3.1610 - Burial in national cemeteries; burial of unclaimed bodies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... cemeteries; burial of unclaimed bodies. 3.1610 Section 3.1610 Pensions, Bonuses, and Veterans' Relief... unclaimed bodies. The statutory burial allowance and permissible transportation charges as provided in §§ 3... from the officers having jurisdiction over burials in national cemeteries; or (b) Where the body of...

  13. 38 CFR 3.1610 - Burial in national cemeteries; burial of unclaimed bodies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... cemeteries; burial of unclaimed bodies. 3.1610 Section 3.1610 Pensions, Bonuses, and Veterans' Relief... unclaimed bodies. The statutory burial allowance and permissible transportation charges as provided in §§ 3... from the officers having jurisdiction over burials in national cemeteries; or (b) Where the body of...

  14. 38 CFR 3.1610 - Burial in national cemeteries; burial of unclaimed bodies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... cemeteries; burial of unclaimed bodies. 3.1610 Section 3.1610 Pensions, Bonuses, and Veterans' Relief... unclaimed bodies. The statutory burial allowance and permissible transportation charges as provided in §§ 3... from the officers having jurisdiction over burials in national cemeteries; or (b) Where the body of...

  15. Land-use change, not climate, controls organic carbon burial in lakes

    PubMed Central

    Anderson, N. J.; Dietz, R. D.; Engstrom, D. R.

    2013-01-01

    Lakes are a central component of the carbon cycle, both mineralizing terrestrially derived organic matter and storing substantial amounts of organic carbon (OC) in their sediments. However, the rates and controls on OC burial by lakes remain uncertain, as do the possible effects of future global change processes. To address these issues, we derived OC burial rates in 210Pb-dated sediment cores from 116 small Minnesota lakes that cover major climate and land-use gradients. Rates for individual lakes presently range from 7 to 127 g C m–2 yr–1 and have increased by up to a factor of 8 since Euro-American settlement (mean increase: 2.8×). Mean pre-disturbance OC burial rates were similar (14–22 g C m–2 yr–1) across all land-cover categories (prairie, mixed deciduous and boreal forest), indicating minimal effect of the regional temperature gradient (approx. 4°C) on background carbon burial. The relationship between modern OC burial rates and temperature was also not significant after removal of the effect of total phosphorus. Contemporary burial rates were strongly correlated with lake-water nutrients and the extent of agricultural land cover in the catchment. Increased OC burial, documented even in relatively undisturbed boreal lake ecosystems, indicates a possible role for atmospheric nitrogen deposition. Our results suggest that globally, future land-cover change, intensification of agriculture and associated nutrient loading together with atmospheric N-deposition will enhance OC sequestration by lakes. PMID:23966637

  16. Isochron-burial dating of glacially-driven sediments: first results from the Alps

    NASA Astrophysics Data System (ADS)

    Akçar, Naki; Ivy-Ochs, Susan; Alfimov, Vasily; Claude, Anne; Reber, Regina; Christl, Marcus; Vockenhuber, Christof; Schlunegger, Fritz; Dehnert, Andreas; Rahn, Meinert; Schlüchter, Christian

    2016-04-01

    The recently introduced method of isochron-burial dating, employs the fact that the samples from a well-defined single bed in a deposit would have the same post-burial but different pre-burial histories. The analysis of cosmogenic 10Be and 26Al in such samples enables the modeling of the post-burial component and the determination of the 26Al/10Be at the time of burial. The isochron-burial age can then be calculated from the initial and the measured ratios. In this study, we focus on the isochron-burial dating of the oldest Quaternary deposits of the Alpine Foreland. These are called Swiss Deckenschotter (cover gravels) as they build mesa-type hill tops on the Mesozoic or Cenozoic bedrock of the Swiss Alpine forelands. Deckenschotter consists of glaciofluvial gravel layers intercalated with glacial and/or overbank deposits. Although previously morphostratigraphically correlated with Günz and Mindel glaciations of Penck and Brückner, the Swiss Deckenschotter is likely much older, and their chronostratigraphy is not well constrained. In order to reconstruct the chronology of these deposits, we collected more than 30 clasts of different lithology, shape and size from a single stratigraphic horizon in an abandoned gravel pit in Siglistorf (canton Zurich). We processed 19 clasts for cosmogenic 10Be and 26Al. Four samples did not yield successful 26Al measurements and two were unsuccessful for 10Be. Most of the samples have low nuclide concentrations, i.e. <20000 10Be at/g and <150000 26Al at/g. Finally, using the 26Al/10Be ratio of the samples we calculated an isochron-burial age of around 1.5 Ma. Our results from this study indicate that glaciofluvial sediments can well be time-calibrated with isochron-burial dating despite the low cosmogenic nuclide concentrations.

  17. Micromorphology of two prehistoric ritual burials from Yemen, and considerations on methodological aspects of sampling the burial matrix - work in progress

    NASA Astrophysics Data System (ADS)

    Usai, Maria-Raimonda; Brothwell, Don; Buckley, Stephen; Ai-Thour, Kalid; Canti, Matthew

    2010-05-01

    Introduction In the central area of Yemen, two burial sites placed high in the crevices of vertical cliff face of Cretaceous sandstone (Tawilah Group) provided evidence of human remains and yielded burial soils. Radiocarbon dating indicated c.2500-2900 years BP for the burials. In other local comparable sites the deep horizontal crevices yielded Bronze Age human remains, in exceptional state of preservation Questions: What was the nature of the burial matrix? Are other human influences superimposed on the soils derived from it? Is it simply decomposed crevice rock, scraped together at the time of burial, or the result of a more complex burial practice? Such questions are also relevant to a variety of other burials of different periods and world regions. Methods Seven matrix samples from Cliff Burials (A) Talan (Layers 4,10,12,14,18,20 and 22, from top to bottom) and (B) Shiban Kawkaban (Layer 1 and 9) were analysed with micromorphology, supplemented by SEM microprobe, X-ray diffraction, gas chromatography/mass spectrometry. Results Cliff Burial Site Talan. The presence of cholesterol was confirmed in the lower sample. The second layer contained darker earth with fibrous plant material. A hard calcareous upper capping contrasted with the other levels of matrix, and it displayed a highly birefingent material with a significant component of uric acid. The other levels had variable organic content and plant inclusions, and possibly pollen. In Layer 10, aromatic acids indicative of balsam and sugar markers suggested plant gum. Cholesterol was the major sterol in Layers 10 and 22, but whilst in Layer 10 its oxidation products were present and cholestanol was abundant as normally in soils, it was only a minor component of Layer 22 where, rather, a significant amount of coprostanol indicated faecal input, and cholesterol oxidation products were absent. Cliff Burial Site Shiban Kawkaban. Although no stratification was visible to the naked eye, variation was observed at a

  18. A Time-Temperature Transistor - An Application of Aging Dynamics

    NASA Astrophysics Data System (ADS)

    Kenning, Gregory

    Aging dynamics occur as systems far from thermodynamic equilibrium evolve towards equilibrium. We have produced a magnetic nanoparticle system composed of Co nanoparticles, which self-assemble during Co deposition on Sb. At a particular time in the formation of the nanoparticles, they are encased in a layer of Sb producing a system far from equilibrium. Magnetization vs. temperature measurements as well as Magnetic Force Microscopy (MFM) indicates that the nanoparticles initially have a large magnetic moment. We observe, as a function of time, an approximately 80% decay in the sample magnetization and an approximately 50% decay in the DC electrical resistivity. MFM suggests that the magnetization decay proceeds from the magnetic nanoparticles losing their net moments possibly due to spin rearrangement. Evidence also suggests that the initial magnetic moments, drive the Sb layer semiconducting. As the net moments of the magnetic nanoparticles decrease, the Sb reverts back to its semi-metal behavior with the accompanying decrease in the electrical resistivity. The magnetization and resistance decays follow the same Arrhenius type behavior. By varying the Co layer thickness, the Arrhenius parameters can be tuned. We have been able to tune the parameters making these materials excellent candidates for sensors for electronically monitoring the age and lifetime of perishable foods.

  19. Shallow land burial technology: Humid

    NASA Astrophysics Data System (ADS)

    Davis, E. C.; Yeh, G. T.

    Trench lining and grouting, are being demonstrated and evaluated experimental trenches containing compacted low-level waste. Two finite-element hydrologic models were developed to model water movement and solute transport at a waste disposal site. Though the economic analysis of the two trench treatments favored Hypalon lining, results of field experiments examining waste hydrologic isolation favored the cement-bentonite grout treatment. Data from water pump-out and water pump-in tests suggest that the original goal of constructing watertight liners in three experimental trenches was not achieved. Trench-cover subsidence measured over two of the three lined trenches did not occur over any of the three grouted or three control (untreated) trenches. Results indicate that the cement-bentonite treatment provides a degree of waste isolation not afforded by the lined and control trenches and should be considered for use at shallow land burial (SLB) sites with water-related problems.

  20. View southwest toward Eldred Avenue from within Friend's Burial Ground, ...

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

    View southwest toward Eldred Avenue from within Friend's Burial Ground, Benjamin Carr Farm in distance through the trees - Friends' Burial Ground, Eldred & Beacon Avenues, Jamestown, Newport County, RI

  1. Sediment Burial Intolerance of Marine Macroinvertebrates.

    PubMed

    Hendrick, Vicki J; Hutchison, Zoë L; Last, Kim S

    2016-01-01

    The marine environment contains suspended particulate matter which originates from natural and anthropogenic sources. Settlement of this material can leave benthic organisms susceptible to smothering, especially if burial is sudden i.e. following storms or activities such as dredging. Their survival will depend on their tolerance to, and their ability to escape from burial. Here we present data from a multi-factorial experiment measuring burial responses incorporating duration, sediment fraction and depth. Six macroinvertebrates commonly found in sediment rich environments were selected for their commercial and/or conservation importance. Assessments revealed that the brittle star (Ophiura ophiura), the queen scallop (Aequipecten opercularis) and the sea squirt (Ciona intestinalis) were all highly intolerant to burial whilst the green urchin (Psammichinus miliaris) and the anemone (Sagartiogeton laceratus), showed intermediate and low intolerance respectively, to burial. The least intolerant, with very high survival was the Ross worm (Sabellaria spinulosa). With the exception of C. intestinalis, increasing duration and depth of burial with finer sediment fractions resulted in increased mortality for all species assessed. For C. intestinalis depth of burial and sediment fraction were found to be inconsequential since there was complete mortality of all specimens buried for more than one day. When burial emergence was assessed O. ophiura emerged most frequently, followed by P. miliaris. The former emerged most frequently from the medium and fine sediments whereas P. miliaris emerged more frequently from coarse sediment. Both A. opercularis and S. laceratus showed similar emergence responses over time, with A. opercularis emerging more frequently under coarse sediments. The frequency of emergence of S. laceratus increased with progressively finer sediment and C. intestinalis did not emerge from burial irrespective of sediment fraction or depth. Finally, and perhaps

  2. Sediment Burial Intolerance of Marine Macroinvertebrates

    PubMed Central

    Hendrick, Vicki J.; Hutchison, Zoë L.; Last, Kim S.

    2016-01-01

    The marine environment contains suspended particulate matter which originates from natural and anthropogenic sources. Settlement of this material can leave benthic organisms susceptible to smothering, especially if burial is sudden i.e. following storms or activities such as dredging. Their survival will depend on their tolerance to, and their ability to escape from burial. Here we present data from a multi-factorial experiment measuring burial responses incorporating duration, sediment fraction and depth. Six macroinvertebrates commonly found in sediment rich environments were selected for their commercial and/or conservation importance. Assessments revealed that the brittle star (Ophiura ophiura), the queen scallop (Aequipecten opercularis) and the sea squirt (Ciona intestinalis) were all highly intolerant to burial whilst the green urchin (Psammichinus miliaris) and the anemone (Sagartiogeton laceratus), showed intermediate and low intolerance respectively, to burial. The least intolerant, with very high survival was the Ross worm (Sabellaria spinulosa). With the exception of C. intestinalis, increasing duration and depth of burial with finer sediment fractions resulted in increased mortality for all species assessed. For C. intestinalis depth of burial and sediment fraction were found to be inconsequential since there was complete mortality of all specimens buried for more than one day. When burial emergence was assessed O. ophiura emerged most frequently, followed by P. miliaris. The former emerged most frequently from the medium and fine sediments whereas P. miliaris emerged more frequently from coarse sediment. Both A. opercularis and S. laceratus showed similar emergence responses over time, with A. opercularis emerging more frequently under coarse sediments. The frequency of emergence of S. laceratus increased with progressively finer sediment and C. intestinalis did not emerge from burial irrespective of sediment fraction or depth. Finally, and perhaps

  3. U-Th Burial Dates on Ostrich Eggshell

    NASA Astrophysics Data System (ADS)

    Sharp, W. D.; Fylstra, N. D.; Tryon, C. A.; Faith, J. T.; Peppe, D. J.

    2015-12-01

    Obtaining precise and accurate dates at archaeological sites beyond the range of radiocarbon dating is challenging but essential for understanding human origins. Eggshells of ratites (large flightless birds including ostrich, emu and others) are common in many archaeological sequences in Africa, Australia and elsewhere. Ancient eggshells are geochemically suitable for the U-Th technique (1), which has about ten times the range of radiocarbon dating (>500 rather than 50 ka), making eggshells attractive dating targets. Moreover, C and N isotopic studies of eggshell provide insights into paleovegetation and paleoprecipitation central to assessing past human-environment interactions (2,3). But until now, U-Th dates on ratite eggshell have not accounted for the secondary origin of essentially all of their U. We report a novel approach to U-Th dating of eggshell that explicitly accounts for secondary U uptake that begins with burial. Using ostrich eggshell (OES) from Pleistocene-Holocene east African sites, we have measured U and 232Th concentration profiles across OES by laser ablation ICP-MS. U commonly peaks at 10s to 100s of ppb and varies 10-fold or more across the ~2 mm thickness of OES, with gradients modulated by the layered structure of the eggshell. Common Th is high near the shell surfaces, but low in the middle "pallisade" layer of OES, making it optimal for U-Th dating. We determine U-Th ages along the U concentration gradient by solution ICP-MS analyses of two or more fractions of the pallisade layer. We then estimate OES burial dates using a simple model for diffusive uptake of uranium. Comparing such "U-Th burial dates" with radiocarbon dates for OES calcite from the same shells, we find good agreement in 7 out of 9 cases, consistent with rapid burial and confirming the accuracy of the approach. The remaining 2 eggshells have anomalous patterns of apparent ages that reveal they are unsuitable for U-Th dating, thereby providing reliability criteria innate

  4. Two contemporaneous mitogenomes from terminal Pleistocene burials in eastern Beringia

    PubMed Central

    Tackney, Justin C.; Potter, Ben A.; Raff, Jennifer; Powers, Michael; Watkins, W. Scott; Warner, Derek; Reuther, Joshua D.; Irish, Joel D.; O’Rourke, Dennis H.

    2015-01-01

    Pleistocene residential sites with multiple contemporaneous human burials are extremely rare in the Americas. We report mitochondrial genomic variation in the first multiple mitochondrial genomes from a single prehistoric population: two infant burials (USR1 and USR2) from a common interment at the Upward Sun River Site in central Alaska dating to ∼11,500 cal B.P. Using a targeted capture method and next-generation sequencing, we determined that the USR1 infant possessed variants that define mitochondrial lineage C1b, whereas the USR2 genome falls at the root of lineage B2, allowing us to refine younger coalescence age estimates for these two clades. C1b and B2 are rare to absent in modern populations of northern North America. Documentation of these lineages at this location in the Late Pleistocene provides evidence for the extent of mitochondrial diversity in early Beringian populations, which supports the expectations of the Beringian Standstill Model. PMID:26504230

  5. Buried Alive: The Behavioural Response of the Mussels, Modiolus modiolus and Mytilus edulis to Sudden Burial by Sediment.

    PubMed

    Hutchison, Zoë L; Hendrick, Vicki J; Burrows, Michael T; Wilson, Ben; Last, Kim S

    2016-01-01

    Sedimentation in the sea occurs through natural processes, such as wave and tidal action, which can be exacerbated during storms and floods. Changes in terrestrial land use, marine aggregate extraction, dredging, drilling and mining are known to result in substantial sediment deposition. Research suggests that deposition will also occur due to the modern development of marine renewable energy. The response to individual burial under three depths of sediment, three sediment fractions and five burial durations was investigated in two mussel species, Modiolus modiolus and Mytilus edulis in specialist mesocosms. Both mussel species showed substantial mortality, which increased with duration of burial and burial by finer sediment fractions. M. modiolus was better able to survive short periods of burial than M. edulis, but at longer durations mortality was more pronounced. No mortality was observed in M. modiolus in burial durations of eight days or less but by 16 days of burial, over 50% cumulative mortality occurred. Under variable temperature regimes, M. edulis mortality increased from 20% at 8°C to over 60% at 14.5 and 20°C. Only M. edulis was able to emerge from burial, facilitated by increased byssus production, laid mostly on vertical surfaces but also on sediment particles. Emergence was higher from coarse sediment and shallow burials. Byssus production in M. edulis was not related to the condition index of the mussels. Results suggest that even marginal burial would result in mortality and be more pronounced in warm summer periods. Our results suggest that in the event of burial, adult M. modiolus would not be able to emerge from burial unless local hydrodynamics assist, whereas a small proportion of M. edulis may regain contact with the sediment water interface. The physiological stress resulting in mortality, contribution of local hydrodynamics to survival and other ecological pressures such as mussels existing in aggregations, are discussed. PMID:26982582

  6. Buried Alive: The Behavioural Response of the Mussels, Modiolus modiolus and Mytilus edulis to Sudden Burial by Sediment

    PubMed Central

    Hutchison, Zoë L.; Hendrick, Vicki J.; Burrows, Michael T.; Wilson, Ben; Last, Kim S.

    2016-01-01

    Sedimentation in the sea occurs through natural processes, such as wave and tidal action, which can be exacerbated during storms and floods. Changes in terrestrial land use, marine aggregate extraction, dredging, drilling and mining are known to result in substantial sediment deposition. Research suggests that deposition will also occur due to the modern development of marine renewable energy. The response to individual burial under three depths of sediment, three sediment fractions and five burial durations was investigated in two mussel species, Modiolus modiolus and Mytilus edulis in specialist mesocosms. Both mussel species showed substantial mortality, which increased with duration of burial and burial by finer sediment fractions. M. modiolus was better able to survive short periods of burial than M. edulis, but at longer durations mortality was more pronounced. No mortality was observed in M. modiolus in burial durations of eight days or less but by 16 days of burial, over 50% cumulative mortality occurred. Under variable temperature regimes, M. edulis mortality increased from 20% at 8°C to over 60% at 14.5 and 20°C. Only M. edulis was able to emerge from burial, facilitated by increased byssus production, laid mostly on vertical surfaces but also on sediment particles. Emergence was higher from coarse sediment and shallow burials. Byssus production in M. edulis was not related to the condition index of the mussels. Results suggest that even marginal burial would result in mortality and be more pronounced in warm summer periods. Our results suggest that in the event of burial, adult M. modiolus would not be able to emerge from burial unless local hydrodynamics assist, whereas a small proportion of M. edulis may regain contact with the sediment water interface. The physiological stress resulting in mortality, contribution of local hydrodynamics to survival and other ecological pressures such as mussels existing in aggregations, are discussed. PMID:26982582

  7. Preliminary report on a glass burial experiment in granite

    SciTech Connect

    Clark, D.E.; Zhu, B.F.; Robinson, R.S.; Wicks, G.G.

    1983-01-01

    Preliminary results of a two-year burial experiment in granite are discussed. Three compositions of simulated alkali borosilicate waste glasses were placed in boreholes approximately 350 meters deep. The glass sample configurations include mini-cans (stainless steel rings into which glass has been cast) and pineapple slices (thin sections from cylindrical blocks). Assemblies of these glass samples were prepared by stacking them together with granite, compacted bentonite and metal rings to provide several types of interfaces that are expected to occur in the repository. The assemblies were maintained at either ambient mine temperature (8 to 10/sup 0/C) or 90/sup 0/C. The glasses were analyzed before burial and after one month storage at 90/sup 0/C. The most extensive surface degradation occurred on the glasses interfaced with bentonite. In general, very little attack was observed on glass surfaces in contact with the other materials. The limited field and laboratory data are compared.

  8. The effect of temperature on organic carbon degradation in marine sediments

    NASA Astrophysics Data System (ADS)

    Malinverno, Alberto; Martinez, Ernesto A.

    2015-12-01

    The degradation of sedimentary particulate organic carbon (POC) is a key carbon cycle process that fuels the deep subseafloor biosphere. The reactivity of POC is expected to decrease with increasing sediment age, severely restricting the energy available to microorganisms. Conversely, increasing temperatures during burial have been proposed to stimulate POC degradation, possibly supplying significant energy to the deep biosphere. To test the importance of temperature, we assembled POC measurements in two global sets of drill sites where sediments underwent either relatively low or high temperatures during burial, which should have resulted in different rates of POC degradation. For ages 5-10 Ma, the decrease of the average POC content with burial is clearly more pronounced in the sites with high temperature histories. Our results support the hypothesis that temperature is one of the fundamental controls on the rate of POC degradation within deeply buried marine sediments.

  9. The effect of temperature on organic carbon degradation in marine sediments

    PubMed Central

    Malinverno, Alberto; Martinez, Ernesto A.

    2015-01-01

    The degradation of sedimentary particulate organic carbon (POC) is a key carbon cycle process that fuels the deep subseafloor biosphere. The reactivity of POC is expected to decrease with increasing sediment age, severely restricting the energy available to microorganisms. Conversely, increasing temperatures during burial have been proposed to stimulate POC degradation, possibly supplying significant energy to the deep biosphere. To test the importance of temperature, we assembled POC measurements in two global sets of drill sites where sediments underwent either relatively low or high temperatures during burial, which should have resulted in different rates of POC degradation. For ages 5–10 Ma, the decrease of the average POC content with burial is clearly more pronounced in the sites with high temperature histories. Our results support the hypothesis that temperature is one of the fundamental controls on the rate of POC degradation within deeply buried marine sediments. PMID:26640172

  10. Solid waste burial grounds interim safety analysis

    SciTech Connect

    Saito, G.H.

    1994-10-01

    This Interim Safety Analysis document supports the authorization basis for the interim operation and restrictions on interim operations for the near-surface land disposal of solid waste in the Solid Waste Burial Grounds. The Solid Waste Burial Grounds Interim Safety Basis supports the upgrade progress for the safety analysis report and the technical safety requirements for the operations in the Solid Waste Burial Grounds. Accident safety analysis scenarios have been analyzed based on the significant events identified in the preliminary hazards analysis. The interim safety analysis provides an evaluation of the operations in the Solid Waste Burial Grounds to determine if the radiological and hazardous material exposures will be acceptable from an overall health and safety standpoint to the worker, the onsite personnel, the public, and the environment.

  11. Cleanup Verification Package for the 618-2 Burial Ground

    SciTech Connect

    W. S. Thompson

    2006-12-28

    This cleanup verification package documents completion of remedial action for the 618-2 Burial Ground, also referred to as Solid Waste Burial Ground No. 2; Burial Ground No. 2; 318-2; and Dry Waste Burial Site No. 2. This waste site was used primarily for the disposal of contaminated equipment, materials and laboratory waste from the 300 Area Facilities.

  12. Impact of temperature on the aging mechanisms of arsenic in soils: fractionation and bioaccessibility.

    PubMed

    Huang, Guanxing; Chen, Zongyu; Wang, Jia; Hou, Qinxuan; Zhang, Ying

    2016-03-01

    The present study focused on the influence of temperature variation on the aging mechanisms of arsenic in soils. The results showed that higher temperature aggravated the decrease of more mobilizable fractions and the increase of less mobilizable or immobilizable fractions in soils over time. During the aging process, the redistribution of both carbonate-bound fraction and specifically sorbed and organic-bound fraction in soils occurred at various temperatures, and the higher temperature accelerated the redistribution of specifically sorbed and organic-bound fraction. The aging processes of arsenic in soils at different temperatures were characterized by several stages, and the aging processes were not complete within 180 days. Arsenic bioaccessibility in soils decreased significantly by the aging, and the decrease was intensified by the higher temperature. In terms of arsenic bioaccessibility, higher temperature accelerated the aging process of arsenic in soils remarkably. PMID:26520097

  13. Plant Sensitivity to Burial and Coastal Foredune Morphology

    NASA Astrophysics Data System (ADS)

    Goldstein, E. B.; Moore, L. J.; deVries, E.; Jass, T. L.; Duran Vinent, O.

    2015-12-01

    Coastal dunes arise from a feedback between plant growth and aeolian sediment transport. Dune plants are uniquely adapted to the harsh coastal environment, and are able to tolerate high temperature, drought, salt spray, and burial by sand. Accurate modeling of coastal dunes relies on understanding how coastal plants respond to these stresses, and how the dune building feedback is modified as a result. We use two years of data from an experimental planting on Hog Island, VA, USA to parameterize a logistic growth model that explicitly includes the effects of plant burial on three species of common dune plants on the US East Coast: Spartina patens, Ammophila breviligulata, and Uniola paniculata. We couple this new plant growth model to the Coastal Dune Model of Durán and Moore (2013). Using this enhanced model we explore the consequences of plant sensitivity to burial on coastal dune growth. These results will add to the growing literature on coupled vegetation and sand transport models, specifically the modeling of coastal dunes.

  14. Effect of Blade Tenderization, Aging Time and Aging Temperature on Tenderness of Beef Longissimus Lumborum and Gluteus Medius

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to evaluate the effects of blade tenderization, aging time, and aging temperature on the tenderness of longissimus lumborum (LL) and gluteus medius (GM) steaks. Beef strip loins (n = 300) and top sirloin butts (n = 300) were selected from a large beef processor and transported...

  15. Stabilization of Fe-C Martensitic Phase by Low-Temperature Ageing

    SciTech Connect

    Dabrowski, L.; Winek, T.; Neov, S.

    2007-04-23

    Martensite containing 0.87 wt.% carbon was aged at liquid nitrogen temperature during 30 days. X-ray diffraction measurements showed that ageing does not lead to the phase transition {alpha} {yields} {kappa} up to 800 K.

  16. Stabilization of Fe-C Martensitic Phase by Low-Temperature Ageing

    NASA Astrophysics Data System (ADS)

    Dabrowski, L.; Neov, S.; Winek, T.

    2007-04-01

    Martensite containing 0.87 wt.% carbon was aged at liquid nitrogen temperature during 30 days. X-ray diffraction measurements showed that ageing does not lead to the phase transition α ==> κ up to 800 K.

  17. General description of the hydrology and burial trenches at the low-level radioactive waste burial facility near Barnwell, South Carolina

    USGS Publications Warehouse

    McDonald, B.B.

    1984-01-01

    The Barnwell low-level radioactive solid waste burial site is located in Barnwell County, South Carolina, 5 miles west of the city of Barnwell. Approximately 1,050 feet of stratified gravel, sand, silt, clay, and limestone, ranging in age from Late Cretaceous to Holocene, underlie the burial site. Ground water within the study area occurs under water table, semi-confined, and artesian conditions. Overland flow and most precipitation that recharges the ground-water system at the burial site is discharged to Marys Branch Creek. This creek originates as a spring about 3,000 feet south of the burial site and flows to the southwest into lower Three Runs. Lower Three Runs discharges into the Savannah River. Waste shipments to the site were reduced from 200,000 cubic feet per month for the period 1971 to 1979 to 100,000 cubic feet per month by October 1981. The wastes consist of both nonfuel cycle and nuclear fuel-cycle wastes. The standard trench dimensions at the burial site are 100 feet wide by 1,000 feet long and 22 feet deep. Trench bottoms are a minimum of 5 feet above the water table. Seven soil mapping units occur at the waste disposal facility. The three major soil types are all well drained and cover approximately 84 percent of the study area. (USGS)

  18. Burial diagenesis of upper Mississippian Greenbrier limestone in central Appalachian basin

    SciTech Connect

    Carney, C.

    1987-09-01

    As carbonate sediments undergo progressive burial under conditions of increasing temperature and pressure, they go through a variety of changes. Burial diagenesis includes processes such as mechanical and chemical compaction, mineralogic change, cementation, dolomitization, and various types of neomorphic fabric change. Identifying the products of burial diagenesis may be useful in predicting porosity and reservoir quality in the subsurface. The Upper Mississippian Greenbrier Limestone and equivalents are exposed throughout the central Appalachians. Important textural and mineralogical changes have been recognized in these shallow shelf limestones, which indicate burial to different depths. Variations in trace- and minor-element concentrations occur with increasing diagenesis. Textural alterations include increased matrix (micrite) crystal size and increased twinning of echinoderm fragments. The Greenbrier Limestone can be divided into three diagenetic provinces. Zone 1, located on the extreme western side of the basin, is characterized by little evidence of compaction, mineralogic variation, or textural change. In this area, the limestones were never buried to any great depth. Zone 3, on the eastern side of the basin, is characterized by significant mechanical and chemical compaction, and mineralogic and textural change. Limestones of this diagenetic province have been subjected to relatively high paleotemperatures during deep burial. Zone 2 is of intermediate burial depth and diagenesis and is present between zones 1 and 3.

  19. An application of Petrochronology: U/Th-Pb geochronologic rates of burial and exhumation in the Cordilleran hinterland, northern Nevada, USA

    NASA Astrophysics Data System (ADS)

    Hallett, B. W.

    2014-12-01

    Monazite and zircon U/Th-Pb dating and yttrium thermometry results from metapelitic rocks of the northern East Humboldt Range, Nevada provide insight into the tectonic evolution of the North American Cordillera. Combining a petrologic approach with in situ U/Th-Pb SHRIMP geochronology gives constraints on the timing and rates of burial and exhumation. When integrated with the results from studies of the intrusive igneous and structural evolution of a complexly deformed crustal block, a broad picture of the behavior of the thickened middle crust in an orogenic wedge begins to emerge. In samples from the upper limb of the south verging Winchell Lake nappe, monazite cores giving moderate YPO4 components yield a mean U-Pb age of 82.8 ± 1.3 Ma representing initial growth near garnet zone conditions. A cycle of burial and heating giving way to decompression and melting, followed by zircon growth accompanied by low YPO4 monazite growth giving a wide range of ages (77.1-62.4 Ma) apparently documents cooling and melt crystallization. Monazite core and zircon ages from these samples bracket the time frame for this cycle through peak pressure and then temperature. Rates of burial therefore are ~1.0­-4.5 mm/year for the Winchell Lake nappe. Migmatitic pelites from the Lizzies Basin area, structurally beneath the Winchell Lake nappe give U-Pb monazite age brackets of 96.5-79.4 Ma, yielding a narrower range of burial rates, ~0.5-2.0 mm/year. Calculated exhumation rates for the same rocks from both the upper limb of the Winchell Lake nappe and the Lizzies Basin area fall between ~0.4 and 1.7 mm/year. Rapid burial followed by rapid exhumation is consistent with thickening by an overthrust mechanism followed by vertical ductile thinning, underplating, erosion, and/or normal faulting. Exhumation is generally slower than estimates for exhumation of metamorphic core complexes north of the Snake River Plain calculated by Bendick and Baldwin (2009). This may represent a difference in

  20. 500,000-year temperature record challenges ice age theory

    USGS Publications Warehouse

    Snow, K. Mitchell

    1994-01-01

    Just outside the searing heat of Death Valley lies Devils Hole (fig. 1), a fault-created cave that harbors two remnants of the Earth's great ice ages. The endangered desert pupfish (Cyprinodon diabolis) has long made its home in the cave. A 500,000-year record of the planet's climate that challenges a widely accepted theory explaining the ice ages also has been preserved in Devils Hole.

  1. Dating of Pliocene Colorado River sediments: implications for cosmogenic burial dating and the evolution of the lower Colorado River

    USGS Publications Warehouse

    Matmon, Ari; Stock, Greg M.; Granger, Darryl E.; Howard, Keith A.

    2011-01-01

    We applied cosmogenic 26Al/10Be burial dating to sedimentary deposits of the ancestral Colorado River. We compared cosmogenic burial ages of sediments to the age of an independently well-dated overlying basalt flow at one site, and also applied cosmogenic burial dating to sediments with less precise independent age constraints. All dated gravels yielded old ages that suggest several episodes of sediment burial over the past ∼5.3 m.y. Comparison of burial ages to the overlying 4.4 Ma basalt yielded good agreement and suggests that under the most favorable conditions, cosmogenic burial dating can extend back 4–5 m.y. In contrast, results from other sites with more broadly independent age constraints highlight the complexities inherent in burial dating; these complexities arise from unknown and complicated burial histories, insufficient shielding, postburial production of cosmogenic isotopes by muons, and unknown initial 26Al/10Be ratios. Nevertheless, and in spite of the large range of burial ages and large uncertainties, we identify samples that provide reasonable burial age constraints on the depositional history of sediment along the lower ancestral Colorado River. These samples suggest possible sediment deposition and burial at ca. 5.3, 4.7, and 3.6 Ma. Our calculated basinwide erosion rate for sediment transported by the modern Colorado River (∼187 mm k.y.−1) is higher than the modern erosion rates inferred from the historic sediment load (80–100 mm k.y.−1). In contrast, basinwide paleo-erosion rates calculated from Pliocene sediments are all under 40 mm k.y.−1 The comparatively lower denudation rates calculated for the Pliocene sediment samples are surprising given that the sampled time intervals include significant Pliocene aggradation and may include much incision of the Grand Canyon and its tributaries. This conflict may arise from extensive storage of sediment along the route of the Colorado River, slower paleobedrock erosion, or the inclusion

  2. Late Quaternary strata and carbon burial records in the Yellow River delta, China

    NASA Astrophysics Data System (ADS)

    Zhao, Guangming; Ye, Siyuan; Li, Guangxue; Ding, Xigui; Yuan, Hongming

    2015-06-01

    Sediment carbon sequestration plays an essential role in mitigating atmospheric CO2 increases and the subsequently global greenhouse effect. To clarify the late Quaternary strata and carbon burial records in Yellow River delta (YRD), detailed analysis of benthic foraminifera, total carbon (TC), organic carbon (Corg), sedimentary characteristics and moisture contents of sediments, was performed on core ZK3, 30.3 m in length and obtained from YRD in 2007. Eight depositional units (designated U1-U8 in ascending order) were identified. A comprehensive analysis method of historical geography and sedimentary geology was used to determine the precise depositional ages of the modern Yellow River delta (MYRD), from which pre-MYRD ages were deduced. The results indicates that the maximum burial rates of TC, inorganic carbon (IC) and Corg occurred in the delta front (U5), and the minimum in the shallow sea (U3). Remarkable high sedimentation rates in the MYRD are responsible for burial efficiency of carbon, with an average rate of Corg burial reaching 2087±251 g (m2 yr)-1, and that of IC reaching 13741±808 g (m2 yr)-1, which are much higher than those of other regions with high contents of Corg. Therefore, YRD has a significant burial efficiency for carbon sequestration.

  3. New Hydroxyproline Radiocarbon Dates from Sungir, Russia, Confirm Early Mid Upper Palaeolithic Burials in Eurasia

    PubMed Central

    Nalawade-Chavan, Shweta; McCullagh, James; Hedges, Robert

    2014-01-01

    Sungir (Russia) is a key Mid-Upper Palaeolithic site in Eurasia, containing several spectacular burials that disclose early evidence for complex burial rites in the form of a range of grave goods deposited along with the dead. Dating has been particularly challenging, with multiple radiocarbon dates ranging from 19,160±270 to 28,800±240 BP for burials that are believed to be closely similar in age. There are disparities in the radiocarbon dates of human bones, faunal remains and charcoal found on the floor of burials [1], [2], [3]. Our approach has been to develop compound-specific methods using High Performance Liquid Chromatography (HPLC) to separate single amino acids, such as hydroxyproline, and thereby avoid the known human contamination on the bones themselves. Previously, we applied this technique to obtain radiocarbon dates of ∼30,000 BP for Sungir 2, Sungir 3 and a mammoth bone from the occupation levels of the site [4]. The single amino acid radiocarbon dates were in good agreement with each other compared to all the dates previously reported, supporting their reliability. Here we report new hydroxyproline dates for two more human burials from the same site, Sungir 1 and Sungir 4. All five hydroxyproline dates reported are statistically indistinguishable and support an identical age for the group. The results suggest that compound-specific radiocarbon analysis should be considered seriously as the method of choice when precious archaeological remains are to be dated because they give a demonstrably contaminant-free radiocarbon age. The new ages are, together with the previously dated ‘Red Lady of Paviland’ human in the British Isles, the earliest for Mid Upper Palaeolithic burial behaviour in Eurasia, and point to the precocious appearance of this form of rite in Europe Russia. PMID:24416120

  4. WATER CONTENT-TEMPERATURE INTERACTIONS REGULATE SEED AGING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water content and temperature are important factors that influence the duration of seed survival in storage. The interacting effect of these two factors and the consequences on seed longevity is rarely recognized. An experiment to quantify the interaction was begun in 1994, using lettuce (Lactuca s...

  5. Effects of sediment burial on grass carp, Ctenopharyngodon idella (Valenciennes,1844), eggs

    USGS Publications Warehouse

    George, Amy E.; Chapman, Duane C.; Deters, Joseph E.; Erwin, Susannah O.; Hayer, Cari-Ann

    2015-01-01

    It is thought that grass carp (Ctenopharyngodon idella) eggs must remain suspended in the water column in order to hatch successfully. Using sand, the effects of varying sediment levels on grass carp eggs were tested at different developmental states and temperatures. Survival was high (15–35%, depending on temperature and trial) in the unburied treatment where eggs rested on a sand bed but were not covered by sediment. Survival was lower in the partial burial (5–10%) and very low (0–4%) in the full burial treatment. In all treatments, delayed hatching (organisms remaining in membranes past the stage of hatching competence) was noted. Deformities such as missing heads and pericardial edema occurred at high rates in the partial and full burials. Eggs that come in contact with the benthos and are resuspended in the water column should be considered in embryonic drift models.

  6. 20 CFR 416.1231 - Burial spaces and certain funds set aside for burial expenses.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... parental deeming situations. If an individual is an eligible child, the burial funds (up to $1,500) that... separation; i.e., a circumstance beyond an individual's control which makes conversion/separation...

  7. Deep-burial diagenesis in carbonates. Final report, January 16, 1984-March 31, 1985

    SciTech Connect

    Friedman, G.M.

    1985-03-01

    The objectives were to gain an understanding of what makes or breaks porosity in carbonate rocks as a result of deep-burial, to develop criteria for deep-burial diagenesis in carbonate rocks, and to apply these criteria for interpretation of carbonate rocks now at shallow depth. Compaction tests reveal that ooid samples show substantial reductions of bulk-volume and porosity when squeezed at temperatures and pressures comparable to overburden of 3.5 to 6.5 km. Particle breakage and deformed particle contacts developed that are comparable to those reported from oolites from the rock record. Reproducibility of pressure solution by compaction supports the conclusion that initial pore-volume reduction through mechanical grain adjustments and ultimate pressure solution are major processes in the diagenetic evolution of limestone. In the deep Analdarko Basin of Oklahoma and Texas, the Hunton Group carbonate rocks of Upper Ordovician to Lower Devonian show that dolostones alone provide porosity. Studies reveal that corrected measurement of bulk densities yield improved estimates of true porosity and water saturation. The mechanism of burial dolomitization was suggested to be the underlying marine Sylvan Shale which provided necessary Mg+2 and Fe+2 during smectite-to-illite transition. Also detailed studies of core samples and thin sections from the Lower Ordovician Ellenberger carbonate rocks in the Permian Basin demonstrated that carbonate rocks below 10,000 ft are exclusively dolostone showing some evidence of deep-burial dolomitization. Lower Ordovician carbonate strata in undeformed belts of the northern Appalachian Basin yield depth of burial and paleotemperature data implying a former depth of burial which has not been usually inferred for this area. Fluid-inclusion suggests burial depth of several kilometers. 41 refs., 12 figs., 2 tabs.

  8. Understanding and controlling low-temperature aging of nanocrystalline materials.

    SciTech Connect

    Battaile, Corbett Chandler; Boyce, Brad Lee; Brons, Justin G.; Foiles, Stephen Martin; Hattar, Khalid Mikhiel; Holm, Elizabeth Ann; Padilla, Henry A.,; Sharon, John Anthony; Thompson, Gregory B.

    2013-10-01

    Nanocrystalline copper lms were created by both repetitive high-energy pulsed power, to produce material without internal nanotwins; and pulsed laser deposition, to produce nan- otwins. Samples of these lms were indented at ambient (298K) and cryogenic temperatures by immersion in liquid nitrogen (77K) and helium (4K). The indented samples were sectioned through the indented regions and imaged in a scanning electron microscope. Extensive grain growth was observed in the lms that contained nanotwins and were indented cryogenically. The lms that either lacked twins, or were indented under ambient conditions, were found to exhibit no substantial grain growth by visual inspection. Precession transmission elec- tron microscopy was used to con rm these ndings quantitatively, and show that 3 and 7 boundaries proliferate during grain growth, implying that these interface types play a key role in governing the extensive grain growth observed here. Molecular dynamics sim- ulations of the motion of individual grain boundaries demonstrate that speci c classes of boundaries - notably 3 and 7 - exhibit anti- or a-thermal migration, meaning that their mobilities either increase or do not change signi cantly with decreasing temperature. An in-situ cryogenic indentation capability was developed and implemented in a transmission electron microscope. Preliminary results do not show extensive cryogenic grain growth in indented copper lms. This discrepancy could arise from the signi cant di erences in con g- uration and loading of the specimen between the two approaches, and further research and development of this capability is needed.

  9. Effect of Blade Tenderization, Aging Time, and Aging Temperature on Tenderness of Beef Longissimus Lumborum and Gluteus Medius

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Purveyors are concerned about the food safety risk of non-intact meat products and are seeking strategies to ensure adequate meat tenderness without blade tenderization. This study was conducted to determine the effects of blade tenderization and time and temperature of aging on beef longissimus lu...

  10. Porosity formation in deep-burial environment: overview, with examples, from Permian basin

    SciTech Connect

    Mazzullo, S.J.; Harris, P.M.

    1989-03-01

    Porosity formation accompanying deep burial is ubiquitous and widespread in the Permian basin, particularly but not exclusively in offshore platform and resedimented basinal carbonates of Pennsylvanian and Permian age. Hydrocarbon reservoirs in such platform carbonate examples locally contain evidence of subaerial exposure and meteoric diagenesis. Commonly, much of the porosity formed during exposure is ultimately reduced by compaction and cementation during early burial. By contrast, no evidence of meteoric diagenesis is observed in associated basinal carbonates, although compaction and cementation accompanying progressive burial are readily evident. In both cases, however, such early diagenesis is overprinted by late burial dissolution, sometimes coincident with hydrocarbon emplacement, creating rocks of high porosity. The formation of porosity by cement dissolution may exhume occluded pores or enhance relict pores that formed in the eogenetic zone, the result being a preponderance of interparticle and moldic pores and residual cements that mimic vadose and phreatic products. In other cases, nonfabric selective dissolution, locally associated with fractures or stylolites, creates vuggy porosity which may resemble that formed during eodiagenesis. Multiple phases of deep-burial dissolution and partial cementation or replacement (by calcite or dolomite) are indicated for many of these diagenetic systems and result in a complex suite of different pore types.

  11. Room Temperature Aging Study of Butyl O-rings

    SciTech Connect

    Mark Wilson

    2009-08-07

    During testing under the Enhanced Surveillance Campaign in 2001, preliminary data detected a previously unknown and potentially serious concern with recently procured butyl o-rings. All butyl o-rings molded from a proprietary formulation throughout the period circa 1999 through 2001 had less than a full cure. Tests showed that sealing force values for these suspect o-rings were much lower than expected and their physical properties were very sensitive to further post curing at elevated temperatures. Further testing confirmed that these o-rings were approximately 50% cured versus the typical industry standard of > 90% cured. Despite this condition, all suspect o-rings fully conformed to their QC acceptance requirements, including their individual product drawing requirements.

  12. Effects of high temperature aging in an impure helium environment on low temperature embrittlement of Alloy 617 and Haynes 230

    NASA Astrophysics Data System (ADS)

    Kim, Daejong; Sah, Injin; Jang, Changheui

    2010-10-01

    The effects of high temperature environmental damage on low temperature embrittlement of wrought nickel-base superalloys, Alloy 617 and Haynes 230 were evaluated. They were aged in an impure helium environment at 1000 °C for up to 500 h before tensile tested at room temperature. The tensile test results showed that the loss of ductility was associated with the increase in the inter-granular fracture with aging time. For Alloy 617, inter-granular oxidation and coarsening of grain boundary carbides contributed to the embrittlement. The significant loss of ductility in Haynes 230 was only observed after 500 h of aging when the globular intermetallic precipitates were extensively formed and brittle inter-granular cracking began to occur.

  13. Burial history influence on the generation of some Italian oils

    SciTech Connect

    Mattavelli, L.; Novelli, L. )

    1990-05-01

    Many Italian oils were sourced by Triassic source rock; evidence of this exists in the Po Plain. In the Adriatic Sea, and offshore southern Sicily. Bulk and geochemical characteristics of these oils are quite dissimilar: heavy oils as well as gasolines were discovered. Such differences are partly attributable to the organic matter type and to environmental conditions, but the role of the source rock's burial histories is fundamental in determining oil characteristics. The different burial histories in these two areas definitely account for these differences. In the Po Plain, the Raethian Argilliti di Riva di Solto Formation, source rock of condensates of the Malossa area, started to generate very early as a consequence of the noticeable Rhaetian-Liassic subsidence. The generation of oil continued for a long geological time, but probably hydrocarbons were lost for the lack of traps. Only condensates, generated by the further Pliocene-Quaternary burial, were accumulated in the Neogene traps. In the western part of the Po Plain, Gaggiano and Villafortuna oils (34 and 40{degree} API), sourced by the Ladinian Meride Formation, were generated only during the sizeable Neogene-Quaternary subsidence. The high heating rate in this case probably enhanced expulsion efficiency, allowing secondary migration toward shallower depths and, consequently, preventing hydrocarbons from secondary cracking. Offshore in southern Sicily (Gela field), the recent subsidence (Pliocene-Pleistocene) is responsible for Triassic source rock maturation. In this case the shallower depth reached by the source rock and, consequently, the lower temperatures at which maturity occurred are partly responsible for the generation of heavy oils, even if other factors such as early expulsion due to tectonics and organic matter type probably play a more important role.

  14. Effect of blade tenderization, aging time, and aging temperature on tenderness of beef longissimus lumborum and gluteus medius.

    PubMed

    King, D A; Wheeler, T L; Shackelford, S D; Pfeiffer, K D; Nickelson, R; Koohmaraie, M

    2009-09-01

    Purveyors are concerned about the potential food safety risk of nonintact meat products and are seeking strategies to ensure adequate meat tenderness without blade tenderization. This study was conducted to determine the effects of blade tenderization and time and temperature of aging on beef longissimus lumborum (LL) and gluteus medius (GM) tenderness. Beef strip loins (n = 300) and top sirloin butts (n = 300) were assigned to storage at -0.5 or 3.3 degrees C for 12, 26, or 40 d. Cuts were blade tenderized (BT) or not blade tenderized (NBT) before steak cutting. One 2.54-cm steak from each subprimal was used for slice shear force determination and Western blotting of desmin. Desmin degradation was less (P < 0.05) in LL stored at -0.5 degrees C than LL stored at 3.3 degrees C (57 and 65%, respectively). Aging from 12 to 26 d increased (P < 0.05) proteolysis (50 to 65%) in LL. Regardless of aging time, BT reduced (P < 0.05) LL slice shear force values. Aging time did not affect (P > 0.05) slice shear force values of BT LL steaks (10.4, 9.9, and 9.4 kg for 12, 26, and 40 d aging, respectively), but reduced (P < 0.05) NBT steak slice shear force values (15.1, 13.8, and 12.3 kg for 12, 26, and 40 d aging, respectively). Greater temperature did not affect (P > 0.05) slice shear force values of BT LL steaks (10.2 and 9.6 kg for steaks aged at -0.5 and 3.3 degrees C, respectively), but improved (P < 0.05) slice shear force of NBT LL steaks (15.1 and 12.4, respectively). Aging at 3.3 degrees C increased (P < 0.05) proteolysis in GM steaks (43 and 54% for -0.5 and 3.3 degrees C, respectively). Longer aging times increased (P < 0.05) proteolysis (40, 46, and 60% for 12, 26, and 40 d aging, respectively) in GM steaks. Blade-tenderized GM steaks had dramatically less (P < 0.05) slice shear force values than NBT steaks (13.7 and 19.9 kg, respectively). Raising aging temperature from -0.5 to 3.3 degrees C reduced (17.6 vs. 16.0 kg; P < 0.05) and increasing aging time from 12 d

  15. Diachronous burial and exhumation of a single tectonic unit during collision orogenesis (Sulitjelma, central Scandinavian Caledonides)

    NASA Astrophysics Data System (ADS)

    Boyle, Alan P.; Burton, Kevin W.; Westhead, R. Keith

    1994-11-01

    The Sulitjelma fold nappe represents part of a Caledonian marginal basin obducted during the closure of the Iapetus Ocean and collision between Laurentia and Baltica. Metamorphic pressure-temperature (P-T) paths indicate that various parts of the Sulitjelma fold nappe followed characteristic clockwise P-T paths involving prograde burial followed by prograde exhumation and then near-isothermal exhumation prior to cooling. Geochronological results indicate that foreland rocks followed this general P-T path before more hinterlandward rocks, such that foreland rocks underwent exhumation while hinterlandward rocks were still being buried. This is consistent with the fold nappe passing through a collisional orogen; burial and ultimately prograde metamorphism were terminated sequentially by exhumation as a given part of the fold nappe came into contact with the lower plate, basement ramp (Baltica) and was driven upward. Burial, heating, exhumation, and cooling were thus diachronous within a single tectonic unit.

  16. Burial at Srebrenica: linking place and trauma.

    PubMed

    Pollack, Craig Evan

    2003-02-01

    Five years after the massacre at Srebrenica in Bosnia-Herzegovina, survivors were faced with the decision: where did they want their loved ones buried? This report explores the reasons for their choice in qualitative interviews with 37 survivors of the massacre and 22 key informants performed over the summer 2000. Survivors wanted the loved ones buried at Potocari, a site just outside of Srebrenica, because it represented the site of ultimate horror, was connected to their sense of home, and underscored the various power relationships. The data points to the importance of place for health. Trauma, as it occurs in particular locations, breaks the sense of attachment to a particular place. Restoring the physical and social environment through burial and memorials mitigates the consequences of the trauma. The burial at Potocari provides a window into the mourning, politics, and recovery after mass violence. PMID:12560012

  17. Lattice Changes in Shape Memory CuZnAl Alloys on Aging at Room Temperature

    NASA Astrophysics Data System (ADS)

    Çakmak, Seyfettýn; Artunç, Ekrem; Kayali, Nejdet; Adigüzel, Osman

    2001-09-01

    The aging behavior of CuZnAl martensites (Cu-21.62 wt.% Zn-5.68 wt.% Al and Cu-24.98 wt.% Zn-4.43 wt.% Al) at about 297 K was studied by analyzing diffraction line profiles obtained by X-ray diffractometry. For the alloys, the change of the lattice parameters and the tetragonality associated with the aging time at room temperature were investigated. The habit planes versus the aging time at room temperature were calculated using the De Vos-Aernoundt-Delaey model, based on the crystallographic theory of Wechsler-Lieberman-Read(WLR), and from the DO3→ 18R martensite transformation theory.

  18. Evidence for a little ice age and recent warming from a borehole temperature data inversion procedure

    SciTech Connect

    Fivez, J.; Thoen, J.

    2004-11-15

    In this article, we apply our analytical theory, published earlier in this journal, to obtain information on the earth surface temperature history from some borehole temperature data. Compared to the results of the five different methods applied to the same temperature data, our method seems to be easier, assumption-free, and yields internally consistent results. The results suggest a cooling a few centuries ago, followed by a continuing warming up to these days, in agreement with a little ice age scenario.

  19. Evaluation of oxidative behavior of polyolefin geosynthetics utilizing accelerated aging tests based on temperature and pressure

    NASA Astrophysics Data System (ADS)

    Li, Mengjia

    Polyolefin geosynthetics are susceptible to oxidation, which eventually leads to the reduction in their engineering properties. In the application of polyolefin geosynthetics, a major issue is an estimate of the materials durability (i.e. service lifetime) under various aging conditions. Antioxidant packages are added to the polyolefin products to extend the induction time, during which antioxidants are gradually depleted and polymer oxidation reactions are prevented. In this PhD study, an improved laboratory accelerating aging method under elevated and high pressure environments was applied to evaluate the combined effect of temperature and pressure on the depletion of the antioxidants and the oxidation of polymers. Four types of commercial polyolefn geosynthetic materials selected for aging tests included HDPE geogrid, polypropylene woven and nonwoven geotextiles. A total of 33 different temperature/pressure aging conditions were used, with the incubation duration up to 24 months. The applied oven temperature ranged from 35°C to 105°C and the partial oxygen pressure ranged from 0.005 MPa to 6.3 MPa. Using the Oxidative Induction Time (OIT) test, the antioxidant depletion, which is correlated to the decrease of the OIT value, was found to follow apparent first-order decay. The OIT data also showed that, the antioxidant depletion rate increased with temperature according to the Arrhenius equation, while under constant temperatures, the rate increased exponentially with the partial pressure of oxygen. A modified Arrhenius model was developed to fit the antioxidant depletion rate as a function of temperature and pressure and to predict the antioxidant lifetime under various field conditions. This study has developed new temperature/pressure incubation aging test method with lifetime prediction models. Using this new technique, the antioxidant lifetime prediction results are close to regular temperature aging data while the aging duration can be reduced considerably

  20. Low-Temperature Aging and Phase Stability of U6Nb

    SciTech Connect

    Hsiung, L M; Briant, C L; Chasse, K R

    2003-11-21

    Aging behavior and phase stability of a water-quenched U-6wt%Nb (U-14at%Nb) alloy artificially aged at 200 C and naturally aged at ambient temperature for 15 years have been investigated using Vickers hardness test, X-ray diffraction analysis, and transmission electron microscopy techniques. Age hardening/softening phenomenon is observed from the artificially aged samples according to microhardness measurement. The age hardening can be rationalized by the occurrence of spinodal decomposition, or fine scale of Nb segregation, which results in the formation of a nano-scale modulated structure within the artificially aged samples. Coarsening of the modulated structure after prolonged aging leads to the age softening. The occurrence of chemical ordering (disorder-order transformation) is found in the naturally aged sample based upon the observations of antiphase domain boundaries (APB's) and superlattice diffraction patterns. A possible superlattice structure is accordingly proposed for the chemically ordered phase observed in the naturally aged alloy sample.

  1. Growth of the Tuolumne Batholith: Zircon Crystallization Temperature, Age and Trace Element Data

    NASA Astrophysics Data System (ADS)

    Matzel, J.; Miller, J.; Mundil, R.; Wooden, J.; Mazdab, F.; Burgess, S.; Paterson, S.; Memeti, V.

    2007-12-01

    Deciphering the intrusive record of magma systems is essential to understanding the links between surface volcanism and the long-term storage and evolution of magma reservoirs. Here we use age and geochemical data from zircon crystals to track mixing between different parts of the Tuolumne Batholith (Sierra Nevada, California). U-Pb zircon TIMS analyses from all locations examined in the batholith exhibit appreciable dispersion of single crystal or crystal fragment ages (several 105 yrs to 1x106 yrs) and, in addition, display distinctly older ages that likely represent zircon crystals entrained from older parts of the Tuolumne magmatic system. Since techniques aimed at eliminating Pb loss (and thus age scatter) have been employed prior to analysis, we interpret the age dispersion to reflect real variation in the timing of zircon crystallization. Two samples that show a high degree of age dispersion (> 1 Myr) were selected for trace element analysis and Ti- in zircon geothermometry by SHRIMP-RG. Crystallization temperatures ranged from 780-640°C and averaged 695°C (aTiO2 0.75 based on presence of titanite). No clear correlation exists between crystal age and temperature, and in most cases, the temperatures from crystal centers are within uncertainty of the temperatures at the rims. Trace element ratios vary systematically with temperature (e.g. decreasing Th/U ratio with decreasing T) and are attributed to fractionation, although neither sample represents strongly fractionated melt. Low total Zr indicates that the magmas were initially undersaturated in zircon when emplaced, which is also consistent with late zircon crystallization. Combined evidence from TIMS age analyses, geothermometry and trace element data suggests that entrainment of zircon from older parts of the magmatic system occurred late in the history of the batholith, and recycling of zircon crystals during successive magmatic injections is compatible with progressive growth of a large, long

  2. Effect of low-temperature aging on the mechanical behavior of ground Y-TZP.

    PubMed

    Pereira, Gkr; Amaral, M; Cesar, P F; Bottino, M C; Kleverlaan, C J; Valandro, L F

    2015-05-01

    This study evaluated the effects of low-temperature aging on the surface topography, phase transformation, biaxial flexural strength, and structural reliability of a ground Y-TZP ceramic. Disc-shaped specimens were manufactured and divided according to two factors: "grinding" - without grinding (as-sintered, Ctrl), grinding with an extra-fine diamond bur (25 µm Xfine) and coarse diamond bur (181 µm Coarse); and "low-temperature-aging" (absence or presence). Grinding was performed using a contra-angle handpiece under water-cooling. Aging was performed in an autoclave at 134 °C, under 2 bar, over a period of 20 h. Surface topography analysis showed an increase in roughness based on grit-size (Coarse>Xfine>Ctrl), and aging promoted different effects on roughness (Ctrl AgCoarse). Grinding and aging promoted an increase in the amount of m-phase, although different susceptibilities to degradation were observed. Weibull analysis showed an increase in characteristic strength after grinding (Coarse=Xfine>Ctrl); however, distinct effects were observed for aging (CtrlCoarse Ag). Weibull moduli were statistically similar. Grinding promoted an increase in characteristic strength as a result of an increase in m-phase content; when the Y-TZP surface was ground by coarse diamond burs followed by aging, characteristic strength was reduced, meaning the low-temperature degradation appeared to intensify for rougher Y-TZP surfaces. PMID:25746851

  3. Possible Origin of Improved High Temperature Performance of Hydrothermally Aged Cu/Beta Zeolite Catalysts

    SciTech Connect

    Peden, Charles HF; Kwak, Ja Hun; Burton, Sarah D.; Tonkyn, Russell G.; Kim, Do Heui; Lee, Jong H.; Jen, H. W.; Cavattaio, Giovanni; Cheng, Yisun; Lambert, Christine

    2012-04-30

    The hydrothermal stability of Cu/beta NH3 SCR catalysts are explored here. In particular, this paper focuses on the interesting ability of this catalyst to maintain and even enhance high-temperature performance for the "standard" SCR reaction after modest (900 °C, 2 hours) hydrothermal aging. Characterization of the fresh and aged catalysts was performed with an aim to identify possible catalytic phases responsible for the enhanced high temperature performance. XRD, TEM and 27Al NMR all showed that the hydrothermally aging conditions used here resulted in almost complete loss of the beta zeolite structure between 1 and 2 hours aging. While the 27Al NMR spectra of 2 and 10 hour hydrothermally-aged catalysts showed significant loss of a peak associated with tetrahedrally-coordinated Al species, no new spectral features were evident. Two model catalysts, suggested by these characterization data as possible mimics of the catalytic phase formed during hydrothermal aging of Cu/beta, were prepared and tested for their performance in the "standard" SCR and NH3 oxidation reactions. The similarity in their reactivity compared to the 2 hour hydrothermally-aged Cu/beta catalyst suggests possible routes for preparing multi-component catalysts that may have wider temperature windows for optimum performance than those provided by current Cu/zeolite catalysts.

  4. Luminescence dating at the archaeological and human burial site at Roonka, South Australia

    NASA Astrophysics Data System (ADS)

    Robertson, G. B.; Prescott, J. R.

    2006-10-01

    Roonka, the Aboriginal habitation and burial site on the River Murray, South Australia, was excavated from 1968 to 1983. In 1983, thermoluminescence (TL) ages were obtained for several fireplaces at the East Bank site. Sandy dune sediments collected from East Bank were also analysed using traditional TL methods and ages were found at depths down to the base at 2.6 m. Now, 20 years on, with optical dating methods well established, it seemed instructive to repeat the measurements using new techniques, specifically the single aliquot regeneration dose protocol. This has provided confirmation of the TL ages and provided an age framework for both the archaeological and geological aspects of Roonka. The ages confirm the archaeological description of the structure of the dune and show that only the top 20% is the Holocene Bunyip formation. The lower part is assigned to the Woorinen Formation, formed during and after the last glacial maximum. Burials at East Bank took place between about 16 and 20 ka, substantially earlier than those on the Roonka Flat, but consistent with the earliest evidence of occupation on the Flat. They are one of the very few securely dated Pleistocene burials in Australia. Whether the individuals were gracile or robust is not known.

  5. Pesticide burial grounds in Poland: a review.

    PubMed

    Gałuszka, Agnieszka; Migaszewski, Zdzisław M; Manecki, Piotr

    2011-10-01

    Obsolete pesticides were stored in Poland from the middle sixties until the late eighties of the 20th century mostly in underground disposal sites, called "pesticide burial grounds" or "pesticide tombs". The total amount of pesticide waste and packaging materials disposed of in these landfills exceeded 20000 Mg. Typically, the content of a pesticide tomb was dominated by organochlorine pesticides (comprising 10-100% of the total waste volume) with DDT as the prevailing compound. Other pesticide types, such as phosphoroorganic, carbamate insecticides, dinitrophenols, phenoxyacids, and inorganic compounds were stored in smaller quantities, usually not exceeding 10-20% of the total waste volume. With the growing awareness of the threats that these landfills posed to the environment, the first inventory for the whole country was made in 1993 and remediation was initiated in 1999. The total amount of waste, which had to be removed from the known pesticide tombs (hazardous substances, contaminated soils, construction materials etc.) was about 100000 Mg. According to the National Waste Management Plan, the reclamation of pesticide tombs was assumed to have been finished by the end of 2010, however, this goal has not been achieved. The aim of this review is to present a historical perspective of pesticide burial grounds in Poland with an emphasis on their creation, function, inventory, and remediation. Based on unpublished reports, and other published materials of limited availability written in Polish, this review may serve as a source of information for representatives of other countries, where remediation of pesticide burial grounds is still in progress. The experience gained over a ten-year period, when restoration of pesticide tombs was implemented in Poland, reveals that there are many obstacles to this action arising not only from technical, but also from economic and social issues. PMID:21531026

  6. Constitutive Modeling and Testing of Polymer Matrix Composites Incorporating Physical Aging at Elevated Temperatures

    NASA Technical Reports Server (NTRS)

    Veazie, David R.

    1998-01-01

    Advanced polymer matrix composites (PMC's) are desirable for structural materials in diverse applications such as aircraft, civil infrastructure and biomedical implants because of their improved strength-to-weight and stiffness-to-weight ratios. For example, the next generation military and commercial aircraft requires applications for high strength, low weight structural components subjected to elevated temperatures. A possible disadvantage of polymer-based composites is that the physical and mechanical properties of the matrix often change significantly over time due to the exposure of elevated temperatures and environmental factors. For design, long term exposure (i.e. aging) of PMC's must be accounted for through constitutive models in order to accurately assess the effects of aging on performance, crack initiation and remaining life. One particular aspect of this aging process, physical aging, is considered in this research.

  7. Cleanup Verification Package for the 118-F-1 Burial Ground

    SciTech Connect

    E. J. Farris and H. M. Sulloway

    2008-01-10

    This cleanup verification package documents completion of remedial action for the 118-F-1 Burial Ground on the Hanford Site. This burial ground is a combination of two locations formerly called Minor Construction Burial Ground No. 2 and Solid Waste Burial Ground No. 2. This waste site received radioactive equipment and other miscellaneous waste from 105-F Reactor operations, including dummy elements and irradiated process tubing; gun barrel tips, steel sleeves, and metal chips removed from the reactor; filter boxes containing reactor graphite chips; and miscellaneous construction solid waste.

  8. Spent fuel temperature and age determination from the analysis of uranium and plutonium isotopics

    SciTech Connect

    Scott, Mark R; Eccleston, George W; Bedell, Jeffrey J; Lockard, Chanelle M

    2009-01-01

    The capability to determine the age (time since irradiation) of spent fuel can be useful for verification and safeguards. While the age of spent fuel can be determined based on measurements of short-lived fission products, these measurements are not routinely done nor generally reported. As an alternative, age can also be determined if the uranium (U) and plutonium (Pu) isotopic values are available. Uranium isotopics are not strongly affected by fuel temperature, and bumup is determined from the {sup 235}U and {sup 236}U isotopic values. Age is calculated after estimating the {sup 241}Pu at the end of irradiation while accounting for the fuel temperature, which is determined from {sup 239}Pu or {sup 240}Pu. Burnup and age determinations are calibrated to reactor models that provide uranium and plutonium isotopics over the range of fuel irradiation. The reactor model must contain sufficient fidelity on details of the reactor type, fuel burnup, irradiation history, initial fuel enrichment and fuel temperature to obtain accurate isotopic calculations. If the latter four are unknown, they can be derived from the uranium and plutonium isotopics. Fuel temperature has a significant affect on the production of plutonium isotopics; therefore, one group cross section reactor models, such as ORIGEN, cannot be used for these calculations. Multi-group cross section set codes, such as Oak Ridge National Laboratory's TRITON code, must be used.

  9. The effect of aging temperature on structure characteristics of ordered mesoporous silicas

    NASA Astrophysics Data System (ADS)

    Deryło-Marczewska, A.; Marczewski, A. W.; Skrzypek, I.; Pikus, S.; Kozak, M.

    2005-10-01

    A series of mesoporous silica materials were synthesized by applying Pluronic type polymers as pore creating agents. In order to differentiate the characteristics of porous structure of the obtained sorbents the temperature of aging process was changed in the synthesis. The parameters characterizing the pore structure were estimated from nitrogen adsorption/desorption isotherms. The changes of pore arrangement of the obtained materials being a result of different synthesis conditions were investigated by using a small angle X-ray scattering method. Correlations between the values of structure parameters and aging temperature were found.

  10. Tectonic significance of precambrian apatite fission-track ages from the midcontinent United States

    USGS Publications Warehouse

    Crowley, K.D.; Naeser, C.W.; Babel, C.A.

    1986-01-01

    Apparent apatite fission-track ages from drill core penetrating basement on the flank of the Transcontinental Arch in northwestern Iowa range from 934 ?? 86 to 641 ?? 90 Ma. These ages, the oldest reported in North America, record at least two thermal events. The 934 Ma age, which is synchronous with KAr ages in the Grenville Province and many KAr whole-rock and RbSr isochron ages from the Lake Superior region, may document basement cooling caused by regional uplift and erosion of the crust. The remaining fission-track ages are products of a more recent thermal event, relative to the age of the samples, which raised temperatures into the zone of partial annealing. Heating may have occurred between the Middle Ordovician and Middle Cretaceous by burial of the basement with additional sediment. It is estimated that burial raised temperatures in the part of the basement sampled by the core to between 50 and 75??C. These temperature estimates imply paleogeothermal gradients of about 20??C/km, approximately two and one-half times present-day values, and burial of the basement by an additional 2-3 km of sediment. ?? 1986.

  11. Burial Diagenesis Effects on Clumped Isotope Signatures of Coexisting Dolomites and Calcites

    NASA Astrophysics Data System (ADS)

    Winkelstern, I. Z.; Lohmann, K. C.

    2014-12-01

    Carbonate clumped isotope paleothermometry is a promising method for diagenetic and deep time paleoclimate studies, but original clumped isotope (Δ47) compositions can be altered by fluid and thermal diagenetic processes. Previous work shows Δ47 resetting of calcite occurs at temperatures exceeding 100°C over time periods of millions of years, but such thermally-driven effects have not been considered for dolomite. Differences between calcite and dolomite temperature calibrations are also largely unquantified, and the effect of burial diagenesis on dolomite Δ47 has not been measured. Coexisting calcites and dolomites in a ~4500 meter core from Andros Island, Bahamas, offer a unique opportunity to address these questions. These dolomites and calcites formed over a time span from the Cretaceous to Pleistocene under near-surface temperature conditions. Clumped isotope analysis of this material reveals that where these carbonate phases are buried to depths greater than ~3000 meters, realistic surface temperatures (~25 °C) are not preserved. Moreover, these phases do not record reasonable geothermal conditions (> 80 °C), but rather record temperatures between 40 and 60°C. Here we evaluate whether this Δ47 "error" is due to solid-state resetting of clumped isotopes, emplacement of minor burial cements, fabric retentive recrystallization, or some combination thereof. Our results show that clumped isotope compositions of both calcite and dolomite respond similarly to diagenetic resetting of primary values under conditions of burial. These data further emphasize the need to constrain the diagenetic history of samples used for clumped isotope work. The similar Δ47 temperatures recorded by each carbonate type suggest that dolomites and calcites are equally viable temperature proxy sources under shallow burial conditions, yet both seem equally susceptible to "resetting" of their primary clumped isotope abundances.

  12. Telomeric attrition with age and temperature in Eastern mosquitofish ( Gambusia holbrooki)

    NASA Astrophysics Data System (ADS)

    Rollings, Nicky; Miller, Emily; Olsson, Mats

    2014-03-01

    Telomeric attrition has repeatedly been found to correlate with the ageing of organisms; however, recent research is increasingly showing that the determinants of attrition dynamics are not well understood. This study examined the relative telomere lengths in Eastern mosquitofish, Gambusia holbrooki, kept at different temperatures and at different ages. Newly born fry were randomly selected for one of four treatment groups: 20, 30, 20-30, and 30-20 °C, where the third and fourth treatment groups were gradually changed from their starting temperature to their final temperature between days 10 and 14. Telomere length was measured, and it was found that length decreased with age and that fish exposed to the 20 °C treatment had significantly shorter telomeres than those that received the 30-20 °C treatment. Telomeric attrition with age agrees with results previously found in studies of telomeres; however, the variation in attrition with temperature was not simply predictable and may be the synergistic effects of temperature and some other factor.

  13. Zonal temperature-anomaly maps of Indian ocean surface waters: modern and ice-age patterns.

    PubMed

    Prell, W L; Hutson, W H

    1979-10-26

    Maps of sea surface temperature anomalies in the Indian Ocean in modern and ice-age times reveal striking changes in its surface circulation. During the last glacial maximum (18,000 years before the present), the Indian Ocean had colder average zonal surface temperatures, a cooler and less extensive Agulhas Current, a distinct eastern boundary current, and decreased upwelling and a weaker southwest monsoon in its northwestern region. PMID:17809371

  14. On the Use of Accelerated Aging Methods for Screening High Temperature Polymeric Composite Materials

    NASA Technical Reports Server (NTRS)

    Gates, Thomas S.; Grayson, Michael A.

    1999-01-01

    A rational approach to the problem of accelerated testing of high temperature polymeric composites is discussed. The methods provided are considered tools useful in the screening of new materials systems for long-term application to extreme environments that include elevated temperature, moisture, oxygen, and mechanical load. The need for reproducible mechanisms, indicator properties, and real-time data are outlined as well as the methodologies for specific aging mechanisms.

  15. Mesozoic burial, Mesozoic and Cenozoic exhumation of the Funeral Mountains core complex, Death Valley, Southeastern California

    NASA Astrophysics Data System (ADS)

    Beyene, Mengesha Assefa

    2011-12-01

    The Funeral Mountains of Death Valley National Park, CA, provide an opportunity to date metamorphism resulting from crustal shortening and subsequent episodic extensional events in the Sevier hinterland. It was not clear whether crustal shortening and thus peak temperature metamorphism in the hinterland of the Sevier-Laramide orogenic wedge have occurred whether in Late Jurassic, Early Cretaceous, Late Cretaceous or somewhere between. Particularly ambiguous is the timing of crustal shortening in the deep levels of the hinterland of the Sevier belt, now manifest in the metamorphic core complexes, and how and when these middle-to-lower crustal rocks were exhumed. A 6-point garnet and a whole rock Savillax isochron from middle greenschist facies pelitic schist of the southeastern Funeral Mountains core complex yields an age of 162.1 +/- 5.8 Ma (2sigma). Composite PT paths determined from growth-zoned garnets from the same samples show a nearly isothermal pressure increase of ˜2 kbar at ˜490°C, suggesting thrust burial at 162.1 +/- 5.8 Ma. A second sample of Johnnie Formation from the comparatively higher metamorphic grade area to the northwest (East of Chloride Cliff) yielded an age of 172.9 +/- 4.9 Ma (2sigma) suggesting an increase of thrust burial age towards the higher grade rocks (northwest part of the core complex), consistent with paleo-depth interpretation and metamorphic grade. 40Ar/ 39Ar muscovite ages along footwall of the Boundary Canyon detachment fault and intra-core Chloride Cliff shear zone exhibit significant 40Ar/39Ar muscovite age differences. For samples from the immediate footwall of BCD, the pattern of ages decreasing toward the northwest is consistent with differences in depth of metamorphism, and for Late Cretaceous, top-to-northwest exhumation by motion along the precursor BCD; consistent with mesoscopic and microscopic kinematic studies. Samples from the footwall of the structurally-lower Chloride Cliff shear zone yield Tertiary 40Ar/39Ar

  16. Structural transition in sputter-deposited amorphous germanium films by aging at ambient temperature

    NASA Astrophysics Data System (ADS)

    Okugawa, M.; Nakamura, R.; Ishimaru, M.; Watanabe, K.; Yasuda, H.; Numakura, H.

    2016-06-01

    The structure of amorphous Ge (a-Ge) films prepared by sputter-deposition and the effects of aging at ambient temperature and pressure were studied by pair-distribution-function (PDF) analysis from electron scattering and molecular dynamics simulations. The PDFs of the as-deposited and aged samples for 3-13 months showed that the major peaks for Ge-Ge bonds decrease in intensity and broaden with aging for up to 7 months. In the PDFs of a-Ge of molecular dynamics simulation obtained by quenching liquid at different rates, the major peak intensities of a slowly cooled model are higher than those of a rapidly cooled model. Analyses on short- and medium-range configurations show that the slowly cooled model includes a certain amount of medium-range ordered (MRO) clusters, while the rapidly cooled model includes liquid-like configurations rather than MRO clusters. The similarity between experimental and computational PDFs implies that as-deposited films are similar in structure to the slowly cooled model, whereas the fully aged films are similar to the rapidly cooled model. It is assumed that as they undergo room-temperature aging, the MRO clusters disintegrate and transform into liquid-like regions in the same matrix. This transition in local configurations is discussed in terms of instability and the non-equilibrium of nanoclusters produced by a vapor-deposition process.

  17. Radioactive Waste Burial Grounds. Environmental Information Document

    SciTech Connect

    Jaegge, W.J.; Kolb, N.L.; Looney, B.B.; Marine, I.W.; Towler, O.A.; Cook, J.R.

    1987-03-01

    This document provides environmental information on postulated closure options for the Radioactive Waste Burial Grounds at the Savannah River Plant and was developed as background technical documentation for the Department of Energy`s proposed Environmental Impact Statement (EIS) on waste management activities for groundwater protection at the plant. The results of groundwater and atmospheric pathway analyses, accident analysis, and other environmental assessments discussed in this document are based upon a conservative analysis of all foreseeable scenarios as defined by the National Environmental Policy Act (CFR, 1986). The scenarios do not necessarily represent actual environmental conditions. This document is not meant to be used as a closure plan or other regulatory document to comply with required federal or state environmental regulations. The closure options considered for the Radioactive Waste Burial Grounds are waste removal and closure, no waste removal and closure, and no action. The predominant pathways for human exposure to chemical and/or radioactive constituents are through surface, subsurface, and atmospheric transport. Modeling calculations were made to determine the risks to human population via these general pathways for the three postulated closure options. An ecological assessment was conducted to predict the environmental impacts on aquatic and terrestrial biota. The relative costs for each of the closure options were estimated.

  18. Relative Burial Depths of Nakhlites: An Update

    NASA Technical Reports Server (NTRS)

    Mikouchi, T.; Miyamoto, M.; Koizumi, E.; Makishima, J.; McKay, G.

    2006-01-01

    Nakhlites are augite-rich cumulate rocks with variable amounts of olivine and groundmass plus minor Fe, Ti oxides [e.g., 1]. Our previous studies revealed that nakhlites showed correlated petrography and mineralogy that could be explained by different locations (burial depths) in a common cooling cumulate pile [e.g., 2]. We so far analyzed six of the seven currently known nakhlites, Nakhla (Nak), Governador Valadares (GV), Lafayette (Laf), NWA817, Y000593 (Y) and MIL03346 (MIL) [e.g., 2,3] and calculated cooling rates of four nakhlites (Nak, GV, Laf, and NWA817) by using chemical zoning of olivine [e.g., 4]. In this abstract, we complete our examination of petrographic and mineralogical variation of all currently known nakhlites by adding petrology and mineralogy of NWA998. We also report results of cooling calculations for Y, MIL and NWA998. Then, we update our model of the nakhlite igneous body in terms of relative burial depth of each sample.

  19. Age-related changes of serum mitochondrial uncoupling 1, rumen and rectal temperature in goats.

    PubMed

    Arfuso, Francesca; Rizzo, Maria; Giannetto, Claudia; Giudice, Elisabetta; Fazio, Francesco; Piccione, Giuseppe

    2016-07-01

    Thermoregulatory processes are induced not only by exposure to cold or heat but also by a variety of physiological situations including age, fasting and food intake that result in changes in body temperature. The aim of the present study was to evaluate the differences in serum mitochondrial uncoupling protein 1 (UCP1), rumen temperature (TRUMEN) and rectal temperature (TRECTAL) values between adult and kids goats. Ten adult male Maltese goats aged 3-5 years old (Group A) and 30 male kids, raised for meat, were enrolled in this study. The kids were equally divided into 3 groups according to their age: Group B included kids aged 3 months, Group C included kids aged 4 months and Group D included kids aged 5 months. Blood samples and measurements of TRUMEN and TRECTAL were obtained from each animal. One-way repeated measures analysis of variance (ANOVA) was applied to evaluate the effect of age on the studied parameters. Statistically significant higher serum UCP1 levels (P<0.001) were found in Group A as compared to Groups B, C and D. Higher TRUMEN values (P<0.001) were found in Group A than in Groups B, C and D, and in Group B than in Groups C and D. Group A showed lower TRECTAL values (P<0.001) than Groups B, C and D. The Pearson's Correlation test was applied to assess significant relationship among studied parameters showing a statistically significant negative correlation between the values of TRECTAL and serum UCP1 in all studied Groups (P<0.001). These results indicate that goats have good control of body temperature suggesting that further details about the thermogenic capacity and the function of UCP1 in kids and adult goats are worth exploring. PMID:27264887

  20. Climate change decouples oceanic primary and export productivity and organic carbon burial

    PubMed Central

    Lopes, Cristina; Kucera, Michal; Mix, Alan C.

    2015-01-01

    Understanding responses of oceanic primary productivity, carbon export, and burial to climate change is essential for model-based projection of biological feedbacks in a high-CO2 world. Here we compare estimates of productivity based on the composition of fossil diatom floras with organic carbon burial off Oregon in the Northeast Pacific across a large climatic transition at the last glacial termination. Although estimated primary productivity was highest during the Last Glacial Maximum, carbon burial was lowest, reflecting reduced preservation linked to low sedimentation rates. A diatom size index further points to a glacial decrease (and deglacial increase) in the fraction of fixed carbon that was exported, inferred to reflect expansion, and contraction, of subpolar ecosystems that today favor smaller plankton. Thus, in contrast to models that link remineralization of carbon to temperature, in the Northeast Pacific, we find dominant ecosystem and sea floor control such that intervals of warming climate had more efficient carbon export and higher carbon burial despite falling primary productivity. PMID:25453073

  1. Climate change decouples oceanic primary and export productivity and organic carbon burial.

    PubMed

    Lopes, Cristina; Kucera, Michal; Mix, Alan C

    2015-01-13

    Understanding responses of oceanic primary productivity, carbon export, and burial to climate change is essential for model-based projection of biological feedbacks in a high-CO2 world. Here we compare estimates of productivity based on the composition of fossil diatom floras with organic carbon burial off Oregon in the Northeast Pacific across a large climatic transition at the last glacial termination. Although estimated primary productivity was highest during the Last Glacial Maximum, carbon burial was lowest, reflecting reduced preservation linked to low sedimentation rates. A diatom size index further points to a glacial decrease (and deglacial increase) in the fraction of fixed carbon that was exported, inferred to reflect expansion, and contraction, of subpolar ecosystems that today favor smaller plankton. Thus, in contrast to models that link remineralization of carbon to temperature, in the Northeast Pacific, we find dominant ecosystem and sea floor control such that intervals of warming climate had more efficient carbon export and higher carbon burial despite falling primary productivity. PMID:25453073

  2. Microstructural Evolution in 2101 Lean Duplex Stainless Steel During Low- and Intermediate-Temperature Aging.

    PubMed

    Maetz, Jean-Yves; Cazottes, Sophie; Verdu, Catherine; Danoix, Frédéric; Kléber, Xavier

    2016-04-01

    The microstructural evolution of a 2101 lean duplex stainless steel (DSS) during isothermal aging from room temperature to 470 °C was investigated using thermoelectric power (TEP) measurements to follow the kinetics, atom probe tomography, and transmission electron microscopy. Despite the low Ni, Cr, and Mo contents, the lean DSS was sensitive to α-α' phase separation and Ni-Mn-Si-Al-Cu clustering at intermediate temperatures. The time-temperature pairs characteristic of the early stages of ferrite decomposition were determined from the TEP kinetics. Considering their composition and locations, the clusters are most likely G phase precursors. PMID:26940550

  3. Asphalt Pavement Aging and Temperature Dependent Properties Using Functionally Graded Viscoelastic Model

    ERIC Educational Resources Information Center

    Dave, Eshan V.

    2009-01-01

    Asphalt concrete pavements are inherently graded viscoelastic structures. Oxidative aging of asphalt binder and temperature cycling due to climatic conditions being the major cause of non-homogeneity. Current pavement analysis and simulation procedures dwell on the use of layered approach to account for these non-homogeneities. The conventional…

  4. Rapid Discoloration of Aged Beef Muscles after Short-Term/Extreme Temperature Abuse during Retail Display

    PubMed Central

    Choi, Yun-Sang

    2016-01-01

    The objective of this study was to evaluate the effects of a short-term/extreme temperature abuse (STA) on color characteristics and oxidative stability of aged beef muscles during simulated retail display. Two beef muscles (longissimus lumborum, LL and semitendinosus, ST) were aged for 7 (A7), 14 (A14), 21 (A21), and 28 d (A28), and further displayed at 2℃ for 7 d. The STA was induced by placing steak samples at 20℃ for 1 h on the 4th d of display. Instrumental and visual color evaluations, ferric ion reducing capacity (FRC) and 2-thiobarbituric acid reactive substances (TBARS) assay were performed. Initially, redness, yellowness and hue angle of all beef muscles were similar, regardless of aging time before display (p>0.05). An increase in postmortem aging time increased lipid oxidation and caused a rapid discoloration after STA during display (p<0.05). ST muscle was more sharply discolored and oxidized after STA, when compared to LL muscle (p<0.05). The FRC value of beef muscles was decreased after 7 d of display (p<0.05). The results from the current study indicate adverse impacts of postmortem aging on color and oxidative stabilities of beef muscles, particularly under temperature abusing conditions during retail display. Thus, developing a specific post-harvest strategy to control quality attributes in retail levels for different muscle types and aging conditions would be required. PMID:27433105

  5. Rapid Discoloration of Aged Beef Muscles after Short-Term/Extreme Temperature Abuse during Retail Display.

    PubMed

    Kim, Hyun-Wook; Setyabrata, Derico; Choi, Yun-Sang; Kim, Yuan H Brad

    2016-01-01

    The objective of this study was to evaluate the effects of a short-term/extreme temperature abuse (STA) on color characteristics and oxidative stability of aged beef muscles during simulated retail display. Two beef muscles (longissimus lumborum, LL and semitendinosus, ST) were aged for 7 (A7), 14 (A14), 21 (A21), and 28 d (A28), and further displayed at 2℃ for 7 d. The STA was induced by placing steak samples at 20℃ for 1 h on the 4th d of display. Instrumental and visual color evaluations, ferric ion reducing capacity (FRC) and 2-thiobarbituric acid reactive substances (TBARS) assay were performed. Initially, redness, yellowness and hue angle of all beef muscles were similar, regardless of aging time before display (p>0.05). An increase in postmortem aging time increased lipid oxidation and caused a rapid discoloration after STA during display (p<0.05). ST muscle was more sharply discolored and oxidized after STA, when compared to LL muscle (p<0.05). The FRC value of beef muscles was decreased after 7 d of display (p<0.05). The results from the current study indicate adverse impacts of postmortem aging on color and oxidative stabilities of beef muscles, particularly under temperature abusing conditions during retail display. Thus, developing a specific post-harvest strategy to control quality attributes in retail levels for different muscle types and aging conditions would be required. PMID:27433105

  6. Temperature dependent ageing mechanisms in Lithium-ion batteries - A Post-Mortem study

    NASA Astrophysics Data System (ADS)

    Waldmann, Thomas; Wilka, Marcel; Kasper, Michael; Fleischhammer, Meike; Wohlfahrt-Mehrens, Margret

    2014-09-01

    The effects of temperatures in the range of -20 °C to 70 °C on the ageing behaviour of cycled Lithium-ion batteries are investigated quantitatively by electrochemical methods and Post-Mortem analysis. Commercial 18650-type high-power cells with a LixNi1/3Mn1/3Co1/3O2/LiyMn2O4 blend cathode and graphite/carbon anode were used as test system. The cells were cycled at a rate of 1 C until the discharge capacity falls below 80% of the initial capacity. Interestingly, an Arrhenius plot indicates two different ageing mechanisms for the ranges of -20 °C to 25 °C and 25 °C to 70 °C. Below 25 °C, the ageing rates increase with decreasing temperature, while above 25 °C ageing is accelerated with increasing temperature. The aged 18650 cells are inspected via scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), inductively coupled plasma (ICP), measurements of electrode thickness and X-ray diffraction (XRD) after disassembly to learn more about the chemical reasons of the degradation. The effect of different temperatures on the electrode polarizations are evaluated by assembling electrodes in pouch cells with reference electrode as a model system. We find that the dominating ageing mechanism for T < 25 °C is Lithium plating, while for T > 25 °C the cathodes show degeneration and the anodes will be increasingly covered by SEI layers.

  7. Effects of aging temperature on microstructural evolution at dissimilar metal weld interfaces

    NASA Astrophysics Data System (ADS)

    Choi, Kyoung Joon; Yoo, Seung Chang; Kim, Taeho; Bahn, Chi Bum; Kim, Ji Hyun

    2015-07-01

    From the earlier study which characterized the region of a fusion boundary between a low-alloy steel (LAS) and a Ni-based weld metal of as-welded and aged samples at 450 °C for a 30-y-equivalent time, it was observed in the microstructure that the aging treatment induced the formation and growth of Cr precipitates in the fusion boundary region because of the thermodynamic driving force. Now, this research extends the text matrix and continues the previous study by compiling all the test data, with an additional aging heat treatment conducted at 400 °C for 15- and 30-y-equivalent times (6450 and 12,911 h, respectively). The results for the extended test matrix primarily represent the common features of and disparities in the effects of thermal aging on the aged samples at two different heat-treatment temperatures (400 and 450 °C). Although no difference was expected between the samples, because the heat treatment conditions simulate thermal aging effects during the same service time of 30 y, the sample aged at 450 °C exhibited slightly more severe effects of thermal aging than the sample aged at 400 °C. Nevertheless, the trends for these effects are similar and the simulation of thermal aging effects for a light-water reactor appears to be reliable. However, according to a simulation of the same degree of thermal aging effects, it appears that the activation energy for Cr diffusion should be larger than the numerical value used in this study.

  8. Low-temperature solute segregation and crack age studies. Final report. [BWR

    SciTech Connect

    Lumsden, J.B.

    1981-06-01

    This work led to a better understanding of the composition changes that occur in grain boundaries which lead to low-temperature sensitization (LTS) of type-304 stainless steel (T304SS) and explored analytic techniques for determining the age of stress corrosion cracks in components removed from BWRs. Grain boundary compositions of the weld-heat-affected zones in several LTS conditions were determined using Auger electron spectroscopy. It was found that chromium depletion and phosphorous segregation progressed with aging time until equilibrium concentrations were reached. The equilibrium phosphorous concentration increased as the sensitizing temperature was decreased. Chromium concentrations as low as 8 at% and phosphorous coverages as high as 26 at% were measured. These results suggest further investigations for determining susceptible grain boundary compositions as a function of temperature and time.

  9. Urban Stream Burial Increases Watershed-Scale Nitrate Export.

    PubMed

    Beaulieu, Jake J; Golden, Heather E; Knightes, Christopher D; Mayer, Paul M; Kaushal, Sujay S; Pennino, Michael J; Arango, Clay P; Balz, David A; Elonen, Colleen M; Fritz, Ken M; Hill, Brian H

    2015-01-01

    Nitrogen (N) uptake in streams is an important ecosystem service that reduces nutrient loading to downstream ecosystems. Here we synthesize studies that investigated the effects of urban stream burial on N-uptake in two metropolitan areas and use simulation modeling to scale our measurements to the broader watershed scale. We report that nitrate travels on average 18 times farther downstream in buried than in open streams before being removed from the water column, indicating that burial substantially reduces N uptake in streams. Simulation modeling suggests that as burial expands throughout a river network, N uptake rates increase in the remaining open reaches which somewhat offsets reduced N uptake in buried reaches. This is particularly true at low levels of stream burial. At higher levels of stream burial, however, open reaches become rare and cumulative N uptake across all open reaches in the watershed rapidly declines. As a result, watershed-scale N export increases slowly at low levels of stream burial, after which increases in export become more pronounced. Stream burial in the lower, more urbanized portions of the watershed had a greater effect on N export than an equivalent amount of stream burial in the upper watershed. We suggest that stream daylighting (i.e., uncovering buried streams) can increase watershed-scale N retention. PMID:26186731

  10. URBAN STREAM BURIAL INCREASES WATERSHED-SCALE NITRATE EXPORT

    EPA Science Inventory

    Nitrogen (N) uptake in streams is an important ecosystem service that may be affected by the widespread burial of streams in stormwater pipes in urban watersheds. We predicted that stream burial reduces the capacity of streams to remove nitrate (NO3-) from the water column by in...

  11. 40 CFR 229.1 - Burial at sea.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Burial at sea. 229.1 Section 229.1 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING GENERAL PERMITS § 229.1 Burial at sea. (a) All persons subject to title I of the Act are hereby granted a general permit...

  12. 40 CFR 229.1 - Burial at sea.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Burial at sea. 229.1 Section 229.1 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING GENERAL PERMITS § 229.1 Burial at sea. (a) All persons subject to title I of the Act are hereby granted a general permit to transport human remains from the...

  13. Fire hazards analysis for solid waste burial grounds

    SciTech Connect

    McDonald, K.M.

    1995-09-28

    This document comprises the fire hazards analysis for the solid waste burial grounds, including TRU trenches, low-level burial grounds, radioactive mixed waste trenches, etc. It analyzes fire potential, and fire damage potential for these facilities. Fire scenarios may be utilized in future safety analysis work, or for increasing the understanding of where hazards may exist in the present operation.

  14. Long-length contaminated equipment burial containers fabrication process procedures

    SciTech Connect

    McCormick, W.A., Fluor Daniel Hanford

    1997-03-11

    These special process procedures cover the detailed step-by-step procedures required by the supplier who will manufacture the Long-Length Contaminated Equipment (LLCE) Burial Container design. Also included are detailed step-by-step procedures required by the disposal process for completion of the LLCE Burial Containers at Hanford.

  15. Urban Stream Burial Increases Watershed-Scale Nitrate Export

    PubMed Central

    Beaulieu, Jake J.; Golden, Heather E.; Knightes, Christopher D.; Mayer, Paul M.; Kaushal, Sujay S.; Pennino, Michael J.; Arango, Clay P.; Balz, David A.; Elonen, Colleen M.; Fritz, Ken M.; Hill, Brian H.

    2015-01-01

    Nitrogen (N) uptake in streams is an important ecosystem service that reduces nutrient loading to downstream ecosystems. Here we synthesize studies that investigated the effects of urban stream burial on N-uptake in two metropolitan areas and use simulation modeling to scale our measurements to the broader watershed scale. We report that nitrate travels on average 18 times farther downstream in buried than in open streams before being removed from the water column, indicating that burial substantially reduces N uptake in streams. Simulation modeling suggests that as burial expands throughout a river network, N uptake rates increase in the remaining open reaches which somewhat offsets reduced N uptake in buried reaches. This is particularly true at low levels of stream burial. At higher levels of stream burial, however, open reaches become rare and cumulative N uptake across all open reaches in the watershed rapidly declines. As a result, watershed-scale N export increases slowly at low levels of stream burial, after which increases in export become more pronounced. Stream burial in the lower, more urbanized portions of the watershed had a greater effect on N export than an equivalent amount of stream burial in the upper watershed. We suggest that stream daylighting (i.e., uncovering buried streams) can increase watershed-scale N retention. PMID:26186731

  16. Circadian and age-related modulation of thermoreception and temperature regulation: mechanisms and functional implications.

    PubMed

    Van Someren, Eus J W; Raymann, Roy J E M; Scherder, Erik J A; Daanen, Hein A M; Swaab, Dick F

    2002-09-01

    At older ages, the circadian rhythm of body temperature shows a decreased amplitude, an advanced phase, and decreased stability. The present review evaluates to what extent these changes may result from age-related deficiencies at several levels of the thermoregulatory system, including thermoreception, thermogenesis and conservation, heat loss, and central regulation. Whereas some changes are related to the aging process per se, others appear to be secondary to other factors, for which the risk increases with aging, notably a decreased level of fitness and physical activity. Moreover, functional implications of the body temperature rhythm are discussed. For example, the relation between circadian rhythm and thermoregulation has hardly been investigated, while evidence showed that sleep quality is dependent on both aspects. It is proposed that the circadian rhythm in temperature in homeotherms should not be regarded as a leftover of ectothermy in early evolution, but appears to be of functional significance for physiology from the level of molecules to cognition. A new view on the functional significance of the circadian rhythm in peripheral vasodilation and the consequent out-of-phase rhythms in skin and core temperature is presented. It is unlikely that the strong, daily occurring, peripheral vasodilation primarily represents heat loss in response to a lowering of set point, since behavioral measures are simultaneously taken in order to prevent heat loss. Several indications rather point towards a supportive role in immunological host defense mechanisms. Given the functional significance of the temperature rhythm, research should focus on the feasibility and effectiveness of methods that can in principle be applied in order to enhance the weakened circadian temperature rhythm in the elderly. PMID:12208240

  17. Role of environmental temperature in aging and longevity: insights from neurolipofuscin.

    PubMed

    Sheehy, M R J

    2002-01-01

    The available evidence for thermal modulation of neurolipofuscin deposition in poikilotherms is reviewed here and additional data are contributed. Mainly decapod crustacean models are employed and neurolipofuscin is treated as an index of physiological aging. In all cases, neurolipofuscin accumulation rate is positively correlated with environmental temperature but there appears to be lowered sensitivity in the thermal mid-range, an 'optimum' temperature for neurolipofuscin accumulation and possibly age-associated variation. The geographical position of the population within the species' thermal range may determine sensitivity of the response. There is seasonal oscillation of neurolipofuscin accumulation rate, providing preliminary evidence for neurolipofuscin turnover with net loss in winter. Spatial and temporal thermal variations of similar magnitude appear to have comparable effects on neurolipofuscin accumulation rate. Such effects may be extreme, suggesting important implications for physiological aging even in homeotherms. Inter-specific comparisons indicate that species-specific neurolipofuscin accumulation rates are positively correlated with habitat temperature and inversely correlated with maximum lifespan and age at maturity. These findings help explain some well-known bioclimatic trends in maturation- and maximum body size, such as Bergmann's rule. They also highlight the fact that global warming is likely to cause significant changes in life history parameters, population dynamics and responses to exploitation for many species. PMID:14764331

  18. Temperature affects longevity and age-related locomotor and cognitive decay in the short-lived fish Nothobranchius furzeri.

    PubMed

    Valenzano, Dario R; Terzibasi, Eva; Cattaneo, Antonino; Domenici, Luciano; Cellerino, Alessandro

    2006-06-01

    Temperature variations are known to modulate aging and life-history traits in poikilotherms as different as worms, flies and fish. In invertebrates, temperature affects lifespan by modulating the slope of age-dependent acceleration in death rate, which is thought to reflect the rate of age-related damage accumulation. Here, we studied the effects of temperature on aging kinetics, aging-related behavioural deficits, and age-associated histological markers of senescence in the short-lived fish Nothobranchius furzeri. This species shows a maximum captive lifespan of only 3 months, which is tied with acceleration in growth and expression of aging biomarkers. These biological peculiarities make it a very convenient animal model for testing the effects of experimental manipulations on life-history traits in vertebrates. Here, we show that (i) lowering temperature from 25 degrees C to 22 degrees C increases both median and maximum lifespan; (ii) life extension is due to reduction in the slope of the age-dependent acceleration in death rate; (iii) lowering temperature from 25 degrees C to 22 degrees C retards the onset of age-related locomotor and learning deficits; and (iv) lowering temperature from 25 degrees C to 22 degrees C reduces the accumulation of the age-related marker lipofuscin. We conclude that lowering water temperature is a simple experimental manipulation which retards the rate of age-related damage accumulation in this short-lived species. PMID:16842500

  19. Mechanical properties improvement of silica aerogel through aging: Role of solvent type, time and temperature

    NASA Astrophysics Data System (ADS)

    Omranpour, H.; Dourbash, A.; Motahari, S.

    2014-05-01

    Effective parameters that enhance mechanical properties during aging were investigated in the present study. Silica aerogels were made from tetraethyl orthosilicate (TEOS), water, methanol and NH4F in molar ratio 1:4:8:2×10-3 using a one-step method. Different time, temperature and aging solvents in aging stage were studied. Subsequently, solvent exchange with n-hexane, modification under TMCS solution and ambient pressure drying (APD) were performed for all samples. The aerogels had densities within the range of 0.1 and 0.6 g/cm3. The FTIR, mechanical properties, density and BET results, porosity, pore volume, pore diameter and surface area of the samples, were discussed. The compression properties of the gel increased with the increase in the time and temperature of aging. It was observed that solvents with more polarity improved polymerization, which enhanced the mechanical properties of the related samples. However, the stresses and capillary forces of water during drying were so large that inhibited "spring-back effect" during APD, and consequently a collapsed silica network with higher density was fabricated. In other words, the specific compression strength and modulus declined drastically. For methanol, alcohols inhibit the reactions inconveniently causing more shrinkage. In aging by n-hexane, capillary pressure declined significantly and thereby shrinkage was eliminated and silica aerogels with low bulk densities (0.095 g/cm3), high specific surface areas (600 m2/g), and large pore volumes (2.6 cm3/g) were synthesized.

  20. High ambient temperature and mortality in California: exploring the roles of age, disease, and mortality displacement.

    PubMed

    Basu, Rupa; Malig, Brian

    2011-11-01

    Investigators have consistently demonstrated associations between elevated temperatures and mortality worldwide. Few have recently focused on identifying vulnerable subgroups, and far fewer have determined whether at least some of the observed effect may be a manifestation of mortality displacement. We examined mean daily apparent temperature and mortality in 13 counties in California during the warm season from 1999 to 2006 to identify age and disease subgroups that are at increased risk, and to evaluate the potential effect of mortality displacement. The time-series method using the Poisson regression was applied for data analysis for single lag days of 0-20 days, and for cumulative average lag days of five and ten days. Significant associations were observed for the same-day (excess risk=4.3% per 5.6 °C increase in apparent temperature, 95% confidence interval: 3.4, 5.2) continuing up to a maximum of three days following apparent temperature exposure for non-accidental mortality. Similar risks were found for mortality from cardiovascular diseases, respiratory diseases, and among children zero to 18 years of age, and adults and the elderly 50 years and older. Since no significant negative effects were observed in the following single or cumulative days, evidence of mortality displacement was not found. Thus, the effect of temperature on mortality appears to be an event that occurs within three days following exposure, and requires immediate attention for prevention. PMID:21981982

  1. Low temperature ageing of silicas Gasil-I and TK800

    NASA Astrophysics Data System (ADS)

    Collins, K. E.; Gonçalves, M. C.; Romero, R. B.; Conz, R. F.; de Camargo, V. R.; Collins, C. H.

    2008-04-01

    Gasil-I (a mesoporous silica) and TK800 (a non-porous pyrogenic silica) were investigated in the early 1970s as standard reference materials. Since then the specific surface areas of both silicas have decreased to ˜85% of their initial values, suggesting that the surface character and the ageing mechanism may be the same for both. Comparisons of the shapes of nitrogen-adsorption isotherms, confirmed by comparisons of the shape ratios for Gasil-I and TK800, indicate that Gasil-I has greater microbore character and a higher absorption at p/ p0 > 0.5 than TK800 and that the isotherm shapes have changed little since 1974. The specific volume of Gasil-I has remained nearly constant during the ageing period but the pore size distribution (PSD) has shifted markedly to higher values. Electron micrographs show that low (room) temperature gas-solid ageing results in similar enlargement at the point of contact between attached secondary particles as that which occurs in hydrothermal ageing. In the gas-solid case, this change, which accounts for the decrease in overall surface area, is attributed to the surface transport of silica material in the presence of near monolayer quantities of adsorbed water. Ageing in this manner is geometry-limited so that the rate of ageing is expected to approach zero, resulting in time-stable silicas.

  2. Tripartite associations among bacteriophage WO, Wolbachia, and host affected by temperature and age in Tetranychus urticae.

    PubMed

    Lu, Ming-Hong; Zhang, Kai-Jun; Hong, Xiao-Yue

    2012-11-01

    A phage density model of cytoplasmic incompatibility (CI), which means lytic phages reduce bacterial density associated with CI, significantly enhances our understanding of the tripartite associations among bacteriophage WO, Wolbachia and host. However, WO may alternate between lytic and lysogenic life cycles or change phage production under certain conditions including temperature, host age and host species background. Here, extreme temperatures can induce an alteration in the life cycle of WO and change the tripartite associations among WO, Wolbachia and CI. Based on the accumulation of the WO load, WO can transform into the lytic life cycle with increasing age. These findings confirmed that the environment plays an important role in the associations among WO, Wolbachia and host. PMID:22669278

  3. Fatigue limit of polycrystalline zirconium oxide ceramics: Effect of grinding and low-temperature aging.

    PubMed

    Pereira, G K R; Silvestri, T; Amaral, M; Rippe, M P; Kleverlaan, C J; Valandro, L F

    2016-08-01

    The following study aimed to evaluate the effect of grinding and low-temperature aging on the fatigue limit of Y-TZP ceramics for frameworks and monolithic restorations. Disc specimens from each ceramic material, Lava Frame (3M ESPE) and Zirlux FC (Ivoclar Vivadent) were manufactured according to ISO:6872-2008 and assigned in accordance with two factors: (1) "surface treatment"-without treatment (as-sintered, Ctrl), grinding with coarse diamond bur (181µm; Grinding); and (2) "low-temperature aging (LTD)" - presence and absence. Grinding was performed using a contra-angle handpiece under constant water-cooling. LTD was simulated in an autoclave at 134°C under 2-bar pressure for 20h. Mean flexural fatigue limits (20,000 cycles) were determined under sinusoidal loading using stair case approach. For Lava ceramic, it was observed a statistical increase after grinding procedure and different behavior after LTD stimuli (Ctrltemperature aging promoted a statistical increase in the fatigue limit (Ctrltemperature aging did not damage the fatigue limit values significantly for both materials evaluated, even though those conditions promoted increase in m-phase. PMID:26828768

  4. Evaluation method of leachate leaking from carcass burial site

    NASA Astrophysics Data System (ADS)

    Park, S.; Kim, H.; Lee, M.; Lee, K.; Kim, S.; Kim, M.; Kim, H.; Kim, T.; Han, J.

    2012-12-01

    More than 150,000 cattle carcasses and 3,140,000 pig carcasses were buried all over the nation in Korea because of 2010 outbreak of foot and mouth disease (FMD). Various disposal Techniques such as incineration, composting, rendering, and burial have been developed and applied to effectively dispose an animal carcass. Since a large number of carcasses should be disposed for a short-term period to prevent the spread of FMD virus, most of the carcasses were disposed by mass burial technique. However, a long-term management and monitoring of leachate discharges are required because mass burial can cause soil and groundwater contamination. In this study, we used key parameters related to major components of leachate such as NH4-N, NO3-N, Cl-, E.coli and electrical conductivity as potential leachate contamination indicator to determine leachate leakage from the site. We monitored 300 monitoring wells in both burial site and the monitoring well 5m away from burial sites to identify leachate leaking from burial site. Average concentration of NH3-N in 300 monitoring wells, both burial site and the well 5m away from burial sites, were 2,593 mg/L and 733 mg/L, respectively. 24% out of 300 monitoring wells showed higher than 10 mg/L NH4-N, 100 mg/L Cl- and than 800 μS/cm electrical conductivity. From this study, we set up 4 steps guidelines to evaluate leachate leakage like; step 1 : High potential step of leachate leakage, step 2 : Middle potential step of leachate leakage, step 3 : Low potential step of leachate leakage, step 4 : No leachate leakage. On the basis of this result, we moved 34 leachate leaking burial sites to other places safely and it is necessary to monitor continuously the monitoring wells for environmental protection and human health.

  5. Investigation of elevated temperature aging effects on lithium-ion cells

    SciTech Connect

    JUNGST,RUDOLPH G.; NAGASUBRAMANIAN,GANESAN; INGERSOLL,DAVID

    2000-04-17

    Electrical and chemical measurements have been made on 18650-size lithium-ion cells that have been exposed to calendar and cycle life aging at temperatures up to 70 C. Aging times ranged from 2 weeks at the highest temperature to several months under more moderate conditions. After aging, the impedance behavior of the cells was reversed from that found originally, with lower impedance at low state of charge and the total impedance was significantly increased. Investigations using a reference electrode showed that these changes are primarily due to the behavior of the cathode. Measurements of cell impedance as a function of cell voltage reveal a pronounced minimum in the total impedance at approximately 40--50% state-of-charge (SOC). Chemical analysis data are presented to support the SOC assignments for aged and unaged cells. Electrochemical impedance spectroscopy (EIS) data have been recorded at several intermediate states of charge to construct the impedance vs. open circuit voltage curve for the cell. This information has not previously been available for the LiNi{sub 0.85}Co{sub 0.15}O{sub 2} cathode material. Structural and chemical analysis information obtained from cell components removed during postmortems will also be discussed in order to reveal the true state of charge of the cathode and to develop a more complete lithium inventory for the cell.

  6. Identification and Tracing Groundwater Contamination by Livestock Burial Sites

    NASA Astrophysics Data System (ADS)

    Ko, K.; Ha, K.; Park, S.; Kim, Y.; Lee, K.

    2011-12-01

    Foot-and-mouth disease (FMD) or hoof-and-mouth disease is a severe plague for animal farming that affects cloven-hoofed animals such as cattle, pigs, sheep, and goats. Since it is highly infectious and can be easily proliferated by infected animals, contaminated equipments, vehicles, clothing, people, and predators. It is widely known that the virus responsible for FMD is a picornavirus, the prototypic member of the genus Aphthovirus. A serious outbreak of foot-and-mouth disease, leading to the stamping out of 3.53 millions of pigs and cattle and the construction of 4,538 burial sites until 15th March, 2011. The build-up of carcass burial should inevitably produce leachate by the decomposition of buried livestock affecting the surround environment such as air, soil, groundwater, and surface water. The most important issues which are currently raised by scientists are groundwater contamination by leachate from the livestock burial sites. This study examined the current status of FMD outbreak occurred in 2010-2011 and the issues of groundwater contamination by leachate from livestock burial sites. The hydrogeochemical, geophysical, and hydrogeological studies were executed to identify and trace groundwater contamination by leachate from livestock burial sites. Generally livestock mortality leachate contains high concentrations of NH3-N, HCO3-, Cl-, SO42-, K+, Na+, P along with relative lesser amounts of iron, calcium, and magnesium. The groundwater chemical data around four burial sites showed high NH3-N, HCO3-, and K+ suggesting the leachate leakage from burial sites. This is also proved by resistivity monitoring survey and tracer tests. The simulation results of leachate dispersion showed the persistent detrimental impacts for groundwater environment for a long time (~50 years). It is need to remove the leachate of burial sites to prevent the dispersion of leachate from livestock burial to groundwater and to monitor the groundwater quality. The most important

  7. Temperature and Pomaceous Flower Age Related to Colonization by Erwinia amylovora and Antagonists.

    PubMed

    Pusey, P L; Curry, E A

    2004-08-01

    ABSTRACT Fire blight of apple and pear is initiated by epiphytic populations of Erwinia amylovora on flower stigmas. Predicting this disease and managing it with microbial antagonists depends on an understanding of bacterial colonization on stigmas. Detached 'Manchurian' crab apple flowers were inoculated with E. amylovora and subjected to a range of constant temperatures or various fluctuating temperature regimes. Results may have application to disease risk assessment systems such as the Cougarblight model, which now are based on in vitro growth of the pathogen. In other experiments, detached crab apple flowers and attached 'Gala' apple flowers were maintained at different temperatures for various periods before inoculation with E. amylovora or antagonists (Pseudomonas fluorescens strain A506 and Pantoea agglomerans strains C9-1 and E325). Maximum stigma age supporting bacterial multiplication decreased as temperature increased, and was reduced by pollination. Stigmas were receptive to bacteria at ages older than previously reported, probably due to less interference from indigenous organisms. The study revealed antagonist limitations that possibly affect field performance (e.g., the inability of strain A506 to grow on relatively old stigmas conducive to the pathogen). Such deficiencies could be overcome by selecting other antagonists or using antagonist mixtures in the orchard. PMID:18943112

  8. Temperature, age and crust thickness distributions of Loki Patera on Io: implications for resurfacing mechanism

    NASA Technical Reports Server (NTRS)

    Davies, A. G.

    2003-01-01

    A high-spatial-resolution, multi-wavelength observation by the Galileo NIMS instrument has been analysed to determine the temperature and area distribution of a large portion of the ionian volcano Loki Patera. The temperatures of the cooler components from a two-temperature fit to the data can be used to determine ages of the surface. The age of the floor along a profile across the floor of the caldera ranges from 10 to 80 days. This puts the start of the resurfacing in July/early August 2001, yielding a resurfacing rate of approximately 1 km/day, with the new lava spreading from the SW corner of the caldera in a NE direction. This rate is consistent with resurfacing by foundering of the crust on a lava lake. However,the temperature distribution may also result from the emplacement of flows. Implied crust thicknesses (derived using a lava cooling model) range from 2.6 to 0.9 m.

  9. Temperature dependence of the transverse piezoelectric coefficient of thin films and aging effects

    SciTech Connect

    Rossel, C. Sousa, M.; Abel, S.; Caimi, D.; Suhm, A.; Abergel, J.; Le Rhun, G.; Defay, E.

    2014-01-21

    We present a technique to measure the temperature dependence of the transverse piezoelectric coefficient e{sub 31,f} of thin films of lead zirconate titanate (PZT), aluminum nitride, and BaTiO{sub 3} deposited on Si wafers. It is based on the collection of electric charges induced by the deflection of a Si cantilever coated with the piezoelectric film. The aim of this work is to assess the role of temperature in the decay of the remnant polarization of these materials, in particular, in optimized gradient-free PZT with composition PbZr{sub 0.52}Ti{sub 0.48}O{sub 3}. It is found that in contrast to theoretical predictions, e{sub 31,f} decreases with temperature because of the dominance of relaxation effects. The observation of steps in the logarithmic aging decay law is reminiscent of memory effects seen in frustrated spin glasses.

  10. Medieval Warm Period, Little Ice Age and 20th century temperature variability from Chesapeake Bay

    USGS Publications Warehouse

    Cronin, T. M.; Dwyer, G.S.; Kamiya, T.; Schwede, S.; Willard, D.A.

    2003-01-01

    We present paleoclimate evidence for rapid (< 100 years) shifts of ??? 2-4??C in Chesapeake Bay (CB) temperature ???2100, 1600, 950, 650, 400 and 150 years before present (years BP) reconstructed from magnesium/calcium (Mg/Ca) paleothermometry. These include large temperature excursions during the Little Ice Age (???1400-1900 AD) and the Medieval Warm Period (???800-1300 AD) possibly related to changes in the strength of North Atlantic thermohaline circulation (THC). Evidence is presented for a long period of sustained regional and North Atlantic-wide warmth with low-amplitude temperature variability between ???450 and 1000 AD. In addition to centennial-scale temperature shifts, the existence of numerous temperature maxima between 2200 and 250 years BP (average ???70 years) suggests that multi-decadal processes typical of the North Atlantic Oscillation (NAO) are an inherent feature of late Holocene climate. However, late 19th and 20th century temperature extremes in Chesapeake Bay associated with NAO climate variability exceeded those of the prior 2000 years, including the interval 450-1000 AD, by 2-3??C, suggesting anomalous recent behavior of the climate system. ?? 2002 Elsevier Science B.V. All rights reserved.

  11. Modelling Anopheles gambiae s.s. Population Dynamics with Temperature- and Age-Dependent Survival.

    PubMed

    Christiansen-Jucht, Céline; Erguler, Kamil; Shek, Chee Yan; Basáñez, María-Gloria; Parham, Paul E

    2015-06-01

    Climate change and global warming are emerging as important threats to human health, particularly through the potential increase in vector- and water-borne diseases. Environmental variables are known to affect substantially the population dynamics and abundance of the poikilothermic vectors of disease, but the exact extent of this sensitivity is not well established. Focusing on malaria and its main vector in Africa, Anopheles gambiae sensu stricto, we present a set of novel mathematical models of climate-driven mosquito population dynamics motivated by experimental data suggesting that in An. gambiae, mortality is temperature and age dependent. We compared the performance of these models to that of a "standard" model ignoring age dependence. We used a longitudinal dataset of vector abundance over 36 months in sub-Saharan Africa for comparison between models that incorporate age dependence and one that does not, and observe that age-dependent models consistently fitted the data better than the reference model. This highlights that including age dependence in the vector component of mosquito-borne disease models may be important to predict more reliably disease transmission dynamics. Further data and studies are needed to enable improved fitting, leading to more accurate and informative model predictions for the An. gambiae malaria vector as well as for other disease vectors. PMID:26030468

  12. Age, temperature and pressure of metamorphism in the Tasriwine Ophiolite Complex, Sirwa, Morocco

    NASA Astrophysics Data System (ADS)

    Samson, S. D.; Inglis, J.; Hefferan, K. P.; Admou, H.; Saquaque, A.

    2013-12-01

    Sm-Nd garnet-whole rock geochronology and phase equilbria modeling have been used to determine the age and conditions of regional metamorphism within the Tasriwine ophiolite complex,Sirwa, Morocco. Pressure and temperature estimates obtained using a NaCaKFMASHT phase diagram (pseudosection) and garnet core and rim compositions predict that garnet growth began at ~0.72GPa and ~615°C and ended at ~0.8GPa and ~640°C. A bulk garnet Sm-Nd age of 645.6 × 1.6 Ma, calculated from a four point isochron that combines whole rock, garnet full dissolution and two successively more aggressive partial dissolutions, provides a precise date for garnet formation and regional metamorphism. The age is nearly 20 million years younger than a previous age estimate of regional metamorphism of 663 × 14 Ma based upon a SHRIMP U-Pb date from rims on zircon from the Irri migmatite. The new data provide further constraints on the age and nature of regional metamorphism in the Anti-Atlas mountains and emphasizes that garnet growth during regional metamorphism may not necessarily coincide with magmatism/anatexis which predominate the signature witnessed by previous U-Pb studies. The ability to couple PT estimates for garnet formation with high precision Sm- Nd geochronology highlights the utility of garnet studies for uncovering the detailed metamorphic history of the Anti-Atlas mountain belt.

  13. Modelling Anopheles gambiae s.s. Population Dynamics with Temperature- and Age-Dependent Survival

    PubMed Central

    Christiansen-Jucht, Céline; Erguler, Kamil; Shek, Chee Yan; Basáñez, María-Gloria; Parham, Paul E.

    2015-01-01

    Climate change and global warming are emerging as important threats to human health, particularly through the potential increase in vector- and water-borne diseases. Environmental variables are known to affect substantially the population dynamics and abundance of the poikilothermic vectors of disease, but the exact extent of this sensitivity is not well established. Focusing on malaria and its main vector in Africa, Anopheles gambiae sensu stricto, we present a set of novel mathematical models of climate-driven mosquito population dynamics motivated by experimental data suggesting that in An. gambiae, mortality is temperature and age dependent. We compared the performance of these models to that of a “standard” model ignoring age dependence. We used a longitudinal dataset of vector abundance over 36 months in sub-Saharan Africa for comparison between models that incorporate age dependence and one that does not, and observe that age-dependent models consistently fitted the data better than the reference model. This highlights that including age dependence in the vector component of mosquito-borne disease models may be important to predict more reliably disease transmission dynamics. Further data and studies are needed to enable improved fitting, leading to more accurate and informative model predictions for the An. gambiae malaria vector as well as for other disease vectors. PMID:26030468

  14. Criticality assessment of TRU burial ground culverts

    SciTech Connect

    Winn, W.G.

    1990-09-26

    An effort to assess the criticality risks of {sup 239}Pu in TRU Burial Ground Culverts has been underway for several years. The concern arose from discrepancies in two types of monitors that have been used to assay the {sup 239}Pu waste prior to storage in 55-gallon drums that are placed in the culverts. One type is the solid waste monitor (SWM), which is based on gamma-ray measurements; the other is the neutron coincidence monitor, which is based on neutron measurements. The NCC was put into routine service after 1985 and has generally yielded higher 239 Pu assays than the SWM. Culverts with pre-1986 waste only had SWM assays of {sup 239}Pu; thus, it was questioned whether their actual {sup 239}Pu loadings could be high enough to pose criticality concerns. Studies to characterize the culvert criticality potential have included appraisal of NCC vs SWM, neutron measurements atop the culverts, gamma-ray measurements atop the culverts, and probabilistic risk analyses. Overall, these studies have implied that the culverts are critically safe; however, their results have not been examined collectively. The present report uses the collective information of the preceding studies to arrive at a more complete assessment of the culvert criticality aspects. A conservative k{sub eff} is estimated for an individual suspicious culvert and a PRA is evaluated for its {open_quotes}worst{close_quotes} drum. These two pieces of information form the basis of the appraisal, but other evidence is also included as support.

  15. Depth of burial experiments at Balapan

    SciTech Connect

    Glenn, L.A.; Myers, S.C.

    1997-11-01

    We report of a series of experiments designed to discriminate underground explosion sources at various depths by means of their seismic signatures at regional distances. This series was a joint effort of the US Department of Energy (DOE), the US Defense Special Weapons Agency (DSWA), and the National Nuclear Center of the Republic of Kazakhstan (NNC). The series consisted of three 25-ton explosions, at depths of 55 m, 300 m, and 50 m. In addition, a 5-ton checkout explosion was fired at a depth of 630 m, and small-scale explosions at each site were carried out so that the empirical Green`s functions could be derived. Broadband and short-period seismic data were recorded at an eight-station network within Kazakhstan, at nominal ranges varying from 100-1500 km, and with good azimuthal coverage for regional phases. In addition, seismic measurements were made at former NRDC sites (BAY and KKL), infrasound recordings were made at the cross array at Kurchatov, and close-in seismic measurements were also made at ranges from ground zero to 20 km. Although the main objective of this series was to study depth-of- burial (DOB) effects on the excitation of regional phases such as LG and RG, and to determine whether peaks in the coda spectral shape correlate well with DOB, a secondary objective was to help calibrate the site of the Kazakhstan seismic network, especially the primary IMS station at MAKanchi, and the auxiliary IMS stations at KURchatov and AKTyubinsk.

  16. Age-related maintenance of eccentric strength: a study of temperature dependence.

    PubMed

    Power, Geoffrey A; Flaaten, Nordan; Dalton, Brian H; Herzog, Walter

    2016-04-01

    With adult aging, eccentric strength is maintained better than isometric strength leading to a higher ratio of eccentric/isometric force production (ECC/ISO) in older than younger adults. The purpose was to investigate the ECC/ISO during electrical activation of the adductor pollicis during lengthening (20-320° s(-1)) contractions in 24 young (n = 12, ∼24 years) and old (n = 12, ∼72 years) males across muscle temperatures (cold ∼19 °C; normal ∼30 °C; warm ∼35 °C). For isometric force, the old were 20-30 % weaker in the normal and cold conditions (P < 0.05) with no difference for the warm condition compared to young (P > 0.05). Half-relaxation time (HRT) did not differ across age for the normal and warm temperatures (P > 0.05), but it slowed significantly for old in the cold condition compared with young (∼15 %; P < 0.05), as well, there was a 20 and 40 % increase in muscle stiffness for the young and old, respectively. ECC/ISO was 50-60 % greater for the cold condition than the normal and warm conditions. There was no age difference in ECC/ISO across ages for the normal and warm conditions (P > 0.05), but for the cold, the old exhibited a 20-35 % higher ECC/ISO than did the young for velocities above 60° s(-1) (P < 0.05). A contributing factor to the elevated ECC/ISO is an increased proportion of weakly compared to strongly bound crossbridges. These findings highlight the relationship (r = 0.70) between intrinsic muscle contractile speed (HRT) and eccentric strength in old age. PMID:27028894

  17. Osteology of a slave burial population from Barbados, West Indies.

    PubMed

    Corruccini, R S; Handler, J S; Mutaw, R J; Lange, F W

    1982-12-01

    A unique seventeenth-nineteenth century slave cemetery population from Newton plantation, Barbados, allows examination of craniodental characters in relation to ethnohistorical data. Age-at-death estimates suggest life expectancy at birth of 29 years and low infant mortality; historical demography, however, suggests life expectancy of 20 years and very high infant mortality. Tooth decay, bilateral tooth loss, periodontal disease, root hypercementosis, and severe enamel hypoplasia are high in frequency. The teeth yield evidence of such cultural practices as pipe-smoking and incisor mutilation. Several skeletal features reflect periodic near-starvation. Directional and fluctuating dental asymmetry, relative tooth size, and hypoplasia distribution suggest slaves experienced considerable weaning trauma; metabolic stress at this time exceeded that of prenatal and immediate postnatal periods. Odontometrics and dental and cranial nonmetric traits indicate that modern Blacks are intermediate between the ancestral slaves and modern Whites but more similar to the latter, suggesting effects of environmental covariance exceed those of genetic admixture. Nonmetric trait distributions show nonrandom patterns according to area of burial in the cemetery, a possible result of family segregation. PMID:6762099

  18. SECTION D, WITH FLAT GROUP BURIAL MARKER AT RIGHT FOREGROUND. ...

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

    SECTION D, WITH FLAT GROUP BURIAL MARKER AT RIGHT FOREGROUND. VIEW TO NORTHWEST. - Rock Island National Cemetery, Rock Island Arsenal, 0.25 mile north of southern tip of Rock Island, Rock Island, Rock Island County, IL

  19. Effects of ration and temperature on growth of age-0 Atlantic sturgeon

    USGS Publications Warehouse

    Kelly, J.L.; Arnold, D.E.

    1999-01-01

    Our objective was to gain insight into the optimum temperature and ration for growth of age-0 Atlantic sturgeon Acipenser oxyrinchus in culture. We conducted two trials, each for 8 weeks. Trial 1 started with 60-g fish, trial 2 started with 0 3-g fish. Water temperatures of 15, 17, and 19??C were used separately in each trial. Rations (dry food, wet weight of fish) for 60-g fish were 0.5, 1.0, and 1.5% of biomass per day, for 0.3-g fish, rations were 3, 5, and 7% of biomass per day. We set up three tank replicates, of equal fish biomass, at each combination of temperature and ration. The highest growth rate in trial 1 (for 60-g fish) was 0.014/d at 15??C and the 1.5% ration, although this growth rate was not significantly different from the growth rate at 17??C and 1.5% ration or at 17??C and 1.0% ration. The highest growth rate in trial 2 (for 0.3-g fish) was 0.067/d at 19??C and the 7.0% ration. Instantaneous growth at these conditions was significantly different from all other combinations of temperature and ration. Although these results may not completely define the temperature and ration under which fish could achieve maximum growth rate, they provide a solid starting point for further development of Atlantic sturgeon culture.

  20. The Hydrologic Characteristics of an Orogenic Wedge During Burial of Pelites

    NASA Astrophysics Data System (ADS)

    Nabelek, P. I.

    2014-12-01

    The burial and exhumation of oceanic sediments in orogenic wedges is one of the most important processes that occur during continental collisions. During progressive burial, pelites lose porosity and permeability, and eventually pass into the lithostatic pressure regime where the porosity and permeability are thought to be very small. However, prograde metamorphic reactions produce fluids that must ascent though the pore space or fractures. The hydrologic characteristics of schists undergoing burial were modeled using the program SUTRAMET, which is a modified version of the program SUTRA (Voss & Provost, 2002) that allows modeling of metamorphic reactions at high pressures and temperatures and incorporates transient porosity and permeability changes due to overpressure and changing volume of the metamorphic assemblage. The initial model crustal section includes a hydrostatic pressure regime to the depth of 5 km with φ ≥ 0.007 and k ≥ 10-17 m2. Within the lithostatic pressure domain, schists have φ ≤ 0.003 and k ≤ 10-18 m2. Below the schists that are undergoing burial (3 or 6 mm/y) is an impermeable substrate with φ = 0. P and T are maintained at the top and the bottom boundaries and P is also maintained at the top of the lithostatic domain. T-dependent thermal diffusivity and heat capacity were applied. The initial T gradient is ~30°/km. The only heat sink is endothermic metamorphic reactions and the only heat source is a small amount of radioactivity. The initial schist was assumed to have 17.9 wt.% qtz, 13.2% ab, 28.7% ksp, 9.0% ms, 22.8% chl, and 8.5% law. By the time it reaches the bottom of the crustal section, metamorphic reactions produce the anhydrous assemblage 14.5% qtz, 7.8% an, 13.7% ab, 36% ksp, 0.2% sil, and 27.5% grt. Results show that fluid pressure remains slightly above lithostatic within the initially lithostatic pressure regime as metamorphic fluids are released, even at the slow burial rate of 3 mm/y, because the fluids pass to the

  1. 25 CFR 20.326 - Does Burial Assistance cover transportation costs?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Does Burial Assistance cover transportation costs? 20.326... cover transportation costs? Transportation costs directly associated with burials are normally a part of the established burial rate. If a provider adds an additional transportation charge to the burial...

  2. Cerebrolysin Accelerates Metamorphosis and Attenuates Aging-Accelerating Effect of High Temperature in Drosophila Melanogaster

    PubMed Central

    Navrotskaya, V.; Vorobyova, L.; Sharma, H.; Muresanu, D.; Summergrad, P.

    2015-01-01

    Cerebrolysin® (CBL) is a neuroprotective drug used for the treatment of neurodegenerative diseases. CBL’s mechanisms of action remain unclear. Involvement of tryptophan (TRP)–kynurenine (KYN) pathway in neuroprotective effect of CBL might be suggested considering that modulation of KYN pathway of TRP metabolism by CBL, and protection against eclosion defect and prolongation of life span of Drosophila melanogaster with pharmacologically or genetically-induced down-regulation of TRP conversion into KYN. To investigate possible involvement of TRP–KYN pathway in mechanisms of neuroprotective effect of CBL, we evaluated CBL effects on metamorphosis and life span of Drosophila melanogaster maintained at 23 °C and 28 °C ambient temperature. CBL accelerated metamorphosis, exerted strong tendency (p = 0.04) to prolong life span in female but not in male flies, and attenuated aging-accelerating effect of high (28 °C) ambient temperature in both female and male flies. Further research of CBL effects on metamorphosis and resistance to aging-accelerating effect of high temperature might offer new insights in mechanisms of its neuroprotective action and expand its clinical applications. PMID:25798213

  3. Changes in CaCO3 Burial Trump the Biological Pump

    NASA Astrophysics Data System (ADS)

    Toggweiler, J.; Dunne, J. P.

    2008-12-01

    The dramatic increases in atmospheric CO2 at the ends of ice ages are usually attributed to a one-two punch coming from the ocean. First, a weakened biological pump vents organically cycled CO2 from the deep ocean via changes in the ventilation of the deep ocean around Antarctica. The initial CO2 increase is then augmented by an enhancement of CaCO3 burial due to a process called CaCO3 compensation (after Broecker, W. S and T.-H. Peng, Global Biogeochem. Cycles, 1, 15-29, 1987). Here, we argue that the importance of the biological pump has been exaggerated. The main effect comes from circulation-induced changes in the burial of CaCO3. As shown in a recent paper by Andreas Schmittner and co-authors (Schmittner, A., E. Brook and J. Ahn, Impact of the ocean's overturning circulation on atmospheric CO2, in Ocean Circulation: Mechanisms and Impacts, Geophys. Monogr. 173, A. Schmittner, J. Chiang, and S. Hemming, eds., pp. 209-246, AGU, 2007) changes in the ventilation of the deep ocean around Antarctica gave rise to 20-30 ppm increases in atmospheric CO2 every 5,000-7,000 years during isotope stages 3 and 4 (30,000 to 70,000 years ago). None of these venting events gave rise to a compensation response. Meanwhile, Jaccard et al. (Science, 308, 1003-1006, 2005) show that all the big CO2 increases during terminations through stage 11 were accompanied by huge increases in CaCO3 burial. This suggests that the enhanced burial of CaCO3 is obligatory rather than compensatory with respect to the dramatic CO2 increases. Broecker and Peng's compensation idea is based on an assumption that the rain of CaCO3 to the sea floor is the same everywhere. More specifically, it assumes that there is no spatial correlation between the production of CaCO3 at the surface and the burial on the sea floor. We find instead that the production and burial of CaCO3 tend to be co-located in regional "hot spots" and that burial in the hot spots balances the input of Ca++ and HCO3- ions in rivers. The

  4. High rates of organic carbon burial in fjord sediments globally

    NASA Astrophysics Data System (ADS)

    Smith, Richard W.; Bianchi, Thomas S.; Allison, Mead; Savage, Candida; Galy, Valier

    2015-06-01

    The deposition and long-term burial of organic carbon in marine sediments has played a key role in controlling atmospheric O2 and CO2 concentrations over the past 500 million years. Marine carbon burial represents the dominant natural mechanism of long-term organic carbon sequestration. Fjords--deep, glacially carved estuaries at high latitudes--have been hypothesized to be hotspots of organic carbon burial, because they receive high rates of organic material fluxes from the watershed. Here we compile organic carbon concentrations from 573 fjord surface sediment samples and 124 sediment cores from nearly all fjord systems globally. We use sediment organic carbon content and sediment delivery rates to calculate rates of organic carbon burial in fjord systems across the globe. We estimate that about 18 Mt of organic carbon are buried in fjord sediments each year, equivalent to 11% of annual marine carbon burial globally. Per unit area, fjord organic carbon burial rates are one hundred times as large as the global ocean average, and fjord sediments contain twice as much organic carbon as biogenous sediments underlying the upwelling regions of the ocean. We conclude that fjords may play an important role in climate regulation on glacial-interglacial timescales.

  5. Tritium in the burial ground of the Savannah River Site

    SciTech Connect

    Hyder, M.L.

    1993-06-01

    This memorandum reviews the available information on tritium-contaminated material discarded to burial grounds. Tritium was the first isotope studied because it represents the most immediate concern with regard to release to the environment. Substantial amounts of tritium are known to be present in the ground water underneath the area, and outcropping of this ground water in springs and seeps has been observed. The response to this release of tritium from the burial ground is a current concern. The amount of tritium emplaced in the burial ground facilities is very uncertain, however, some general conclusions can be made. In particular, most of the tritium buried is associated with spent equipment and other waste, rather than spent melts. Correspondingly, most of the tritium in the ground water seems to be associated with burials of this type, rather than the spent melts. Maps are presented showing the location of burials of tritiated waste by type, and the location of the largest individual burials according to COBRA records.

  6. Source of silicate and carbonate cements during deep burial diagenesis

    SciTech Connect

    Dutta, P.K.

    1986-05-01

    Detrital silicate minerals and silicate cements (formed during shallow burial) of siliciclastic sandstones commonly dissolve during deep burial diagenesis. Quartz, feldspars, mica, and garnet among detrital silicate minerals, and quartz and kaolinite among authigenic silicate minerals show extensive dissolution features during deep burial diagenesis of siliciclastic sandstones of the Gondwana Supergroup, India. No dissolution features were observed in zircon, tourmalene, and rutile among detrital minerals or in chlorite and smectite among early formed authigenic minerals. Dissolution enriched the pore fluids in silica, potassium, sodium, calcium, magnesium, iron, and aluminum. Authigenic cements formed during this stage are illite, quartz, feldspar, iron oxide, and carbonates of calcium, magnesium, and iron. Mass-balance calculations show that the source of all silicate cements formed during deep burial diagenesis was internally derived from the dissolution of both detrital and early formed authigenic cements. However, a considerable gap exists between the amounts of cations (calcium, magnesium, and iron) derived internally and the respective amounts of these cations needed to form the various carbonate cements at this stage. Therefore, an outside source for these cations is needed to explain the formation of carbonate cements. A large mass transfer of cations from outside the sediment source seems remote since ground-water movement, which probably carried cement from an external source, is extremely restricted at great burial depths. Therefore, carbonate cements may have been major constituents during shallow burial diagenesis in Gondwana sandstones. Subsequently, these early formed carbonates were completely dissolved and remobilized as late-stage carbonate cement.

  7. Hydrology of the Melton Valley radioactive-waste burial grounds at Oak Ridge National Laboratory, Tennessee

    SciTech Connect

    Webster, D.A.; Bradley, M.W.

    1988-12-31

    Burial grounds 4, 5, and 6 were used sequentially from 1951 to the present for the disposal of solid, low-level radioactive waste by burial in shallow trenches and auger holes. Abundant rainfall, a generally thin unsaturated zone, geologic media of inherently low permeability, and the operational practices employed have contributed to partial saturation of the buried waste, leaching of radionuclides, and transport of dissolved matter from the burial areas. Two primary methods of transport from these sites are by dissolution in circulating ground water, and the overflow of fluids in trenches and subsequent flow across land surface. The waste-disposal areas are underlain by the Conasauga Group (Cambrian age), a complex sequence of mudstone, siltstone, and limestone interbeds grading from one lithotype to the other, both laterally and vertically. Compressional forces that caused regional thrust faulting also caused much internal deformation of the beds. Folds, bedding-plane faults, and joints are widespread. Small solution openings have developed in some areas where the structurally-related openings have provided ingress to ground water.

  8. Long-term stabilization of deep soil carbon by fire and burial during early Holocene climate change

    NASA Astrophysics Data System (ADS)

    Marin-Spiotta, Erika; Chaopricha, Nina T.; Plante, Alain F.; Diefendorf, Aaron F.; Mueller, Carsten W.; Grandy, A. Stuart; Mason, Joseph A.

    2014-06-01

    Buried soils contain large reservoirs of organic carbon at depths that are not typically included in regional and global soil carbon inventories. One such palaeosol, the Brady soil of southwestern Nebraska, USA, is buried under six metres of loess. The Brady soil developed at the land surface on the late-Pleistocene-aged Peoria Loess in a period of warmth and wetness during which dunefields and dust sources across the region were stabilized. Abrupt climate change in the early Holocene led to increased loess deposition that buried the soil. Here, we used spectroscopic and isotopic analyses to determine the composition and stability of organic carbon in the Brady soil. We identify high levels of black carbon, indicating extensive biomass burning. In addition, we found intact vascular plant lipids in soil organic matter with radiocarbon ages ranging from 10,500 to 12,400 cal yr BP, indicating decomposition was slowed by rapid burial at the start of the Holocene. We conclude that landscape disturbance caused by abrupt climate change, fire and the loss of vegetative cover contributed to deep carbon sequestration as the soil was quickly buried under accumulating loess. We suggest that terrestrial soil carbon storage in arid and semi-arid environments could undergo landscape-scale shifts in response to rising temperatures, increased fire activity or drought.

  9. Manure source and age affect survival of zoonotic pathogens during aerobic composting at sublethal temperatures.

    PubMed

    Erickson, Marilyn C; Smith, Chris; Jiang, Xiuping; Flitcroft, Ian D; Doyle, Michael P

    2015-02-01

    Heat is the primary mechanism by which aerobic composting inactivates zoonotic bacterial pathogens residing within animal manures, but at sublethal temperatures, the time necessary to hold the compost materials to ensure pathogen inactivation is uncertain. To determine the influence of the type of nitrogen amendment on inactivation of Salmonella, Listeria monocytogenes, and Escherichia coli O157:H7 in compost mixtures stored at sublethal temperatures, specific variables investigated in these studies included the animal source of the manure, the initial carbon/nitrogen (C:N) ratio of the compost mixture, and the age of the manure. Salmonella and L. monocytogenes were both inactivated more rapidly in chicken and swine compost mixtures stored at 20°C when formulated to an initial C:N ratio of 20:1 compared with 40:1, whereas a C:N ratio did not have an effect on inactivation of these pathogens in cow compost mixtures. Pathogen inactivation was related to the elevated pH of the samples that likely arises from ammonia produced by the indigenous microflora in the compost mixtures. Indigenous microbial activity was reduced when compost mixtures were stored at 30°C and drier conditions (<10% moisture level) were prevalent. Furthermore, under these drier conditions, Salmonella persisted to a greater extent than L. monocytogenes, and the desiccation resistance of Salmonella appeared to convey cross-protection to ammonia. Salmonella persisted longer in compost mixtures prepared with aged chicken litter compared with fresh chicken litter, whereas E. coli O157:H7 survived to similar extents in compost mixtures prepared with either fresh or aged cow manure. The different responses observed when different sources of manure were used in compost mixtures reveal that guidelines with times required for pathogen inactivation in compost mixtures stored at sublethal temperatures should be dependent on the source of nitrogen, i.e., type of animal manure, present. PMID:25710145

  10. Effect of Burial Depth on the Clumped Isotope Thermometer: An Example from the Green River and Washakie Basins (WY)

    NASA Astrophysics Data System (ADS)

    Lacroix, B.; Niemi, N. A.

    2014-12-01

    The mass-47 clumped isotope thermometer allows one to elucidate the temperature of carbonate formation and avoids speculation about the composition of precipitating water and/or oxygen composition of another mineral phase, as is required for conventional stable isotope thermometry. Recent studies have tried to reconstruct surface paleotemperatures to resolve paleoclimate or paleoelevation using this technique. Mass-47 measured from carbonates preserved in the geologic record; however, are potentially affected by burial and/or diagenetic alteration. These effects are poorly understood. Here we investigate the effect of burial on the ∆-47 composition of lacustrine carbonates. We collected samples, on the surface and recovered from drill cores, from two regions in the greater Green River Basin (Wyoming), the Washakie Basin and the Pinedale Anticline. Both basins were filled with thick, continuous Cretaceous - Eocene lacustrine strata. From these two sections, lacustrine carbonates were sampled over a paleodepth range of 1-6 km. The ∆-47 compositions of the carbonates have been measured over the first two kilometers of depth and the clumped temperatures compared with peak temperatures estimated from vitrinite reflectance, fluid inclusion thermometry and basin thermal models. Although slightly warmer than MAT estimates from Eocene paleosol geochemistry (~24°C), clumped isotope temperatures are consistently ~40°C across this depth range, similar to clumped-isotope paleotemperature estimates for the Eocene Bighorn Basin. Peak temperatures of the carbonate samples reached 120°C, while modern downhole temperatures of the deepest samples are 50°C. These results suggest that the ∆-47 thermometer preserves a record of surficial temperatures during Eocene time and that the ∆-47 thermometry is not apparently affected by burial to temperatures of at least 120°C. Effects of burial to greater depths (~6 km) and higher temperatures (~200°C) is in progress to evaluate

  11. Characterization of polymers in the glass transition range: Time-temperature and time-aging time superposition in polycarbonate

    SciTech Connect

    Pesce, J.J.; Niemiec, J.M.; Chiang, M.Y.

    1995-12-31

    Here we present time-temperature and time-aging time superposition data for a commercial grade polycarbonate. The data reduction is performed for dynamic-mechanical data obtained in torsion over a range of temperatures from 103.6 to 144.5{degrees}C and aging times to 16 h. For time-temperature superposition the results show the deviation of the sub-T{sub g} response from the WTF equation. Two response regimes are observed: at temperatures far below T{sub g} the log(a{sub T}) is linear in T, followed by a transition towards the WLF behavior as T{sub g} is approached. The temperature at which the behavior changes from a linear dependence of log(aT) on T to the transition-type behavior is found to depend on the aging time. This temperature decreases as aging time increases. The time-aging time response is found to behave in a normal way. At temperatures far below T{sub g} the log(a{sub te}) vs log(t{sub e}) is constant and has a slope somewhat less than unity. However, nearer to T{sub g} the slope decreases and there is a second regime in which the aging virtually ceases. In this polycarbonate, above 136.9{degrees}C, no aging is observed.

  12. Multiple Palaeoproterozoic carbon burial episodes and excursions

    NASA Astrophysics Data System (ADS)

    Martin, A. P.; Prave, A. R.; Condon, D. J.; Lepland, A.; Fallick, A. E.; Romashkin, A. E.; Medvedev, P. V.; Rychanchik, D. V.

    2015-08-01

    Organic-rich rocks (averaging 2-5% total organic carbon) and positive carbonate-carbon isotope excursions (δ13C > + 5 ‰ and locally much higher, i.e. the Lomagundi-Jatuli Event) are hallmark features of Palaeoproterozoic successions and are assumed to archive a global event of unique environmental conditions following the c. 2.3 Ga Great Oxidation Event. Here we combine new and published geochronology that shows that the main Palaeoproterozoic carbon burial episodes (CBEs) preserved in Russia, Gabon and Australia were temporally discrete depositional events between c. 2.10 and 1.85 Ga. In northwest Russia we can also show that timing of the termination of the Lomagundi-Jatuli Event may have differed by up to 50 Ma between localities, and that Ni mineralisation occurred at c. 1920 Ma. Further, CBEs have traits in common with Mesozoic Oceanic Anoxic Events (OAEs); both are exceptionally organic-rich relative to encasing strata, associated with contemporaneous igneous activity and marked by organic carbon isotope profiles that exhibit a stepped decrease followed by a stabilisation period and recovery. Although CBE strata are thicker and of greater duration than OAEs (100 s of metres versus metres, ∼106 years versus ∼105 years), their shared characteristics hint at a commonality of cause(s) and feedbacks. This suggests that CBEs represent processes that can be either basin-specific or global in nature and a combination of circumstances that are not unique to the Palaeoproterozoic. Our findings urge circumspection and re-consideration of models that assume CBEs are a Deep Time singularity.

  13. Fission-track analysis of apatite and zircon defines a burial depth of 4 to 7 km for lowermost Upper Devonian, Catskill Mountains, New York

    NASA Astrophysics Data System (ADS)

    Lakatos, Stephen; Miller, Donald S.

    1983-02-01

    Apatite and zircon grains separated from a sandstone layer of earliest Late Devonian age, Catskill Mountains, have been subjected to fission-track analysis. A 125-m.y. age, obtained on the apatite grains, requires a temperature for the sediment of less than 120 °C during the past 125 m.y. At some time prior to 125 m.y. ago, temperatures were above 120 °C long enough to cause complete fading of tracks. Analysis of zircon grains resulted in a fission-track age of 320 m.y. Zircon data indicate that the temperature of the sediment layer enclosing the grains did not exceed 175 to 200 °C over a 235-rn.y. period (time between sedimentation and 125 m.y. ago). If one assumes a typical geothermal gradient of 25 °C/km, a burial depth of between 4 and 7 km is indicated for the lowermost Upper Devonian, atskill Mountains. *Present address: Rensselaer Polytechnic Institute, Troy, New York 12181

  14. Effect of different aging temperatures prior to freezing on meat quality attributes of frozen/thawed lamb loins.

    PubMed

    Choe, Ju-Hui; Stuart, Adam; Kim, Yuan H Brad

    2016-06-01

    The objective of this study was to determine the effect of different aging temperatures prior to freezing on quality attributes of frozen/thawed lamb loins. The loins (M. longissimus lumborum; n=32) were randomly allocated to one of the four different aging/freezing treatments: aged only (-1.5°C for 14days) and aged (-1.5°C for 14days, 3°C for 8days, or 7°C for 8days) then frozen/thawed loins. The loins aged at elevated temperatures (3°C or 7°C) for 8days had equivalent shear force, protein degradation and purge loss values compared to the loins aged at -1.5°C for 14days (P>0.05). However, significantly higher drip loss and less color stability were observed in the loins with increasing aging temperatures compared to the loins aged at -1.5°C. These results suggest that application of elevated aging temperatures could shorten required aging periods prior to freezing, while not adversely affecting tenderness and purge loss of frozen/thawed meat. PMID:26890391

  15. A comparison of the effect of temperature and moisture on the solid dispersions: aging and crystallization.

    PubMed

    Tian, Bin; Zhang, Ling; Pan, Zhendong; Gou, Jingxin; Zhang, Yu; Tang, Xing

    2014-11-20

    The purpose of this work was to compare the effect of temperature and relative humidity (RH) on the physical stability and dissolution of solid dispersions. Cinnarizine-Soluplus(®) solid dispersions (SDs) at three different drug loadings (10, 20 and 35 wt%) were prepared by hot melt extrusion and exposed to stress conditions: high temperatures (40 and 60 °C), high relative humidities (75% and 94% RH) and accelerated conditions (40 °C/75% RH) for 30 days, or stored at 25 °C for up to 5 months. Changes in solid state and dissolution of SDs were investigated by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and dissolution testing. For samples under stress conditions, the results showed a reduced dissolution and a recrystallization of the drug with an increased crystallinity in the order of 40 °C/75% RH, >60 °C/0% RH, >25 °C/94% RH, >40 °C/0% RH, >25 °C/75% RH. For samples stored at 25 °C, nonlinear physical aging was observed and the dissolution also decreased although the SDs were still amorphous. The results indicated that temperature and humidity seemed to have comparable effects on the crystallization of cinnarizine-Soluplus(®) SDs. It is not reasonable to regard recrystallization as a sign of reduced dissolution, and glass transition temperature (Tg) may be a good indicator of the changes in dissolution. PMID:25218489

  16. Improving tribological performance of gray cast iron by laser peening in dynamic strain aging temperature regime

    NASA Astrophysics Data System (ADS)

    Feng, Xu; Zhou, Jianzhong; Mei, Yufen; Huang, Shu; Sheng, Jie; Zhu, Weili

    2015-09-01

    A high and stable brake disc friction coefficient is needed for automobile safety, while the coefficient degrades due to elevated temperature during the braking process. There is no better solution except changes in material composition and shape design optimization. In the dynamic strain aging(DSA) temperature regime of gray cast iron, micro-dimples with different dimple depth over diameter and surface area density are fabricated on the material surface by laser peening(LP) which is an LST method. Friction behavior and wear mechanism are investigated to evaluate the effects of surface texturing on the tribological performance of specimens under dry conditions. Through LP impacts assisted by DSA, the friction coefficients of the LPed specimens increase noticeably both at room temperature and elevated temperature in comparison to untreated specimens. Moreover, the coefficient of specimen with dimple depth over diameter of 0.03 and surface area density of 30% is up to 0.351 at room temperature, which dramatically rises up to 1.33 times that of untextured specimen and the value is still up to 0.3305 at 400°C with an increasing ratio of 35% compared to that of untreated specimen. The surface of textured specimen shows better wear resistance compared to untreated specimen. Wear mechanism includes adhesive wear, abrasive wear and oxidation wear. It is demonstrated that LP assisted by DSA can substantially improve wear resistance, raise the friction coefficient as well as its stability of gray cast iron under elevated temperatures. Heat fade and premature wear can be effectively relieved by this surface modification method.

  17. Organic carbon burial in a mangrove forest, margin and intertidal mud flat

    NASA Astrophysics Data System (ADS)

    Sanders, Christian J.; Smoak, Joseph M.; Naidu, A. Sathy; Sanders, Luciana M.; Patchineelam, Sambasiva R.

    2010-12-01

    The flux of total organic carbon (TOC) to depositional facies (intertidal mud flat, margin and forest) was quantified for a tropical mangrove forest in Brazil. Results indicate that these mangrove margins and intertidal mudflats are sites of large TOC accumulation, almost four times greater than the global averages for mangrove forests. The TOC burial rates were determined from organic carbon content in sediment cores which were dated using 210Pb. Burial rates were calculated to be 1129, 949, and 353 (g m -2 yr -1), for the mud flat, margin and forest, respectively. Sediment accumulation rates (SAR) were estimated to be 7.3, 5.0 and 2.8 mm yr -1. Sediment characterization (δ 13C, δ 15N, TOC/TN and mud fraction) indicated a representative mangrove system with a record of consistent organic matter flux of up to 100 years. Because of substantial burial of organic carbon in mangrove ecosystems, their role in the global carbon budget must be considered. More importantly, as climate change influences temperature and sea level, mangrove ecosystems will respond to specific climatic conditions.

  18. Early-age cold conditioning of broilers: effects of timing and temperature.

    PubMed

    Shahir, M H; Dilmagani, S; Tzschentke, B

    2012-01-01

    1. The aim of the present study was to determine the effects of early-age cold conditioning (CC) on performance, ascites mortality, thyroid hormones status and immune response (leucocytes count) of broiler chickens. 2. A total of 336 chicks at 2 and 3 d of age were exposed to 20 or 25°C (for 3 or 6 h) in a 2 × 2 × 2 factorial experiment, while a control group was kept under normal temperature conditions (30°C). Thereafter, both control and cold conditioned birds were reared under standard conditions until 42 d of age. 3. The results showed that performance (weight gain and feed efficiency) was improved by CC at the end of the rearing period. Carcase traits (breast, thigh and abdominal fat percentage) were not affected by different treatments. Heart weight was lower in cold conditioned birds accompanied with lower ascites mortality. Total leucocyte count was higher in CC birds. Higher concentrations of thyroxin (T(4)) were found in plasma of treated groups, while triiodothyronine (T(3)) to T(4) ratio was decreased. 4. In conclusion, it seems that early age CC improves performance and reduces ascites mortality of broilers through altered thyroid hormones metabolism and leucocyte function. According to the results, the best timing for CC of broilers was 20°C for 6 h at the age of 2 d, and no significant benefit was observed by repeated CC. PMID:23130589

  19. Design and evaluation of a bioreactor with application to forensic burial environments.

    PubMed

    Dunphy, Melissa A; Weisensee, Katherine E; Mikhailova, Elena A; Harman, Melinda K

    2015-12-01

    Existing forensic taphonomic methods lack specificity in estimating the postmortem interval (PMI) in the period following active decomposition. New methods, such as the use of citrate concentration in bone, are currently being considered; however, determining the applicability of these methods in differing environmental contexts is challenging. This research aims to design a forensic bioreactor that can account for environmental factors known to impact decomposition, specifically temperature, moisture, physical damage from animals, burial depth, soil pH, and organic matter content. These forensically relevant environmental variables were characterized in a soil science context. The resulting metrics were soil temperature regime, soil moisture regime, slope, texture, soil horizon, cation exchange capacity, soil pH, and organic matter content. Bioreactor chambers were constructed using sterilized thin-walled polystyrene boxes housed in calibrated temperature units. Gravesoil was represented using mineral soil (Ultisols), and organic soil proxy for Histosols, horticulture mix. Gravesoil depth was determined using mineral soil horizons A and Bt2 to simulate surface scatter and shallow grave burial respectively. A total of fourteen different environmental conditions were created and controlled successfully over a 90-day experiment. These results demonstrate successful implementation and control of forensic bioreactor simulating precise environments in a single research location, rather than site-specific testing occurring in different geographic regions. Bone sections were grossly assessed for weathering characteristics, which revealed notable differences related to exposure to different temperature regimes and soil types. Over the short 90-day duration of this experiment, changes in weathering characteristics were more evident across the different temperature regimes rather than the soil types. Using this methodology, bioreactor systems can be created to replicate many

  20. Thallium isotope a new tool for tracking the global marine ferromanganese burial

    NASA Astrophysics Data System (ADS)

    Owens, J. D.; Nielsen, S.

    2014-12-01

    Thallium (Tl) isotopes are an emerging proxy with the potential to track surficial redox processes. To date Tl isotopes have not been extensively explored for the entire range of redox condition in the modern ocean. Thallium has a relatively short residence time, ~20 thousand years, however new and existing seawater data shows that the modern, dominantly oxic, ocean remains conservative with respect to concentration and isotopes. Past studies have shown that there are only two geologic processes that impart a large isotopic fractionation (1) adsorption onto manganese oxides and (2) low temperature oceanic crust alteration. However, for relatively short term redox events it is reasonable to assume that the dominate isotope fractionation process is associated with manganese oxide precipitation. We present new water column and sediment, authigenic and detrital, Tl isotope data from the Black Sea and Cariaco Basins - the largest permanently anoxic basins in the modern ocean. Preliminary authigenic sediment data from these anoxic basins suggest these settings effectively capture the seawater value. Combining new and existing oxic open ocean data along with calculated fluxes constrain the mass balance of Tl, which shows the ability to fingerprint the global extent of manganese oxide burial and thus infer the extent of oxic seafloor burial. Combining thallium isotopes with other reliable paleoredox proxies such as molybdenum (Mo) isotopes and can help to elucidate global redox events. We have employed a quantitative model to explore the possible utility of multiple isotope systems such as the links between Mo and Tl isotopes. As a case study, we have modeled Tl and Mo isotopes during the Toarcian oceanic anoxic event where thallium isotopes in early diagenetic pyrite and have shown the potential to record excursions in the local and/or possibly global burial of manganese oxides. This modeling exercise has shown that Tl isotopes lend insight into the global marine oxic

  1. "Interred with their bones" - linking soil micromorphology and chemistry to unlock the hidden archive of archaeological human burials

    NASA Astrophysics Data System (ADS)

    Brothwell, Don; Usai, Maria-Raimonda; Keely, Brendan; Pickering, Matt; Wilson, Clare

    2010-05-01

    "Interred with their bones" Acronym: InterArChive - an ERC-funded project *** " Friends, Romans, countrymen, lend me your ears; " I come to bury Caesar, not to praise him. " The evil that men do lives after them; " The good is oft 'interred with their bones'; " So let it be with Caesar. William Shakespeare, Julius Caesar, Act III, Scene 2. *** Background The state of decay within soils in archaeological graves is often such that degradable objects are not preserved in a condition that can be visually recognised. However, microscopic soil features, inorganic element distributions and organic residues can be measured. Thus, archaeological burial soils have the potential to reveal signatures of decay; pre-burial treatment; presence and nature of associated clothing and perishable artefacts; diet of the individual; cause of death; evidence of morbidity and drug-use. Aims • To develop and test a multidisciplinary approach linking soil micromorphology and chemistry to recover environmental and cultural information; • Revealing the hidden archaeological archive within the burial soil • Developing soil sampling and analysis recommendations for archaeological human burials Methods 1: Sampling and soil field description from archaeological sites contrasting in soil, geology, age, and culture and from experimental piglet burials 2: Microscopic/micromorphological analysis (micro-scale observations) of remains and features in burial soils. We will establish the order of occurrence, spatial patterns, displacement, mode of formation and decay of micromorphological features including exotic components, parasites, hair and remnants of footwear and clothing [cf. pilot study of soils from Yemen]; microfabrics and textural pedofeatures, also to facilitate resolution of body decay products from other accumulations. 3: Microprobe analysis (nano-scale) will generate elemental maps of soil thin sections, allowing identification of features with distinct chemical signatures

  2. Asphalt pavement aging and temperature dependent properties using functionally graded viscoelastic model

    NASA Astrophysics Data System (ADS)

    Dave, Eshan V.

    Asphalt concrete pavements are inherently graded viscoelastic structures. Oxidative aging of asphalt binder and temperature cycling due to climatic conditions being the major cause of non-homogeneity. Current pavement analysis and simulation procedures dwell on the use of layered approach to account for these non-homogeneities. The conventional finite-element modeling (FEM) technique discretizes the problem domain into smaller elements, each with a unique constitutive property. However the assignment of unique material property description to an element in the FEM approach makes it an unattractive choice for simulation of problems with material non-homogeneities. Specialized elements such as "graded elements" allow for non-homogenous material property definitions within an element. This dissertation describes the development of graded viscoelastic finite element analysis method and its application for analysis of asphalt concrete pavements. Results show that the present research improves efficiency and accuracy of simulations for asphalt pavement systems. Some of the practical implications of this work include the new technique's capability for accurate analysis and design of asphalt pavements and overlay systems and for the determination of pavement performance with varying climatic conditions and amount of in-service age. Other application areas include simulation of functionally graded fiber-reinforced concrete, geotechnical materials, metal and metal composites at high temperatures, polymers, and several other naturally existing and engineered materials.

  3. The (RH+t) aging correlation. Electrical resistivity of PVB at various temperatures and relative humidities

    NASA Technical Reports Server (NTRS)

    Cuddihy, E. F.

    1985-01-01

    Electrical products having organic materials functioning as pottants, encapsulants, and insulation coatings are commonly exposed to elevated conditions of temperature and humidity. In order to assess service life potential from this method of accelerated aging, it was empirically observed that service life seems proportional to an aging correlation which is the sum of temperature in degrees Celsius (t), and the relative humidity (RH) expressed in percent. Specifically, the correlation involves a plot of time-to-failure on a log scale versus the variable RH + T plotted on a linear scale. A theoretical foundation is provided for this empirically observed correlation by pointing out that the correlation actually involves a relationship between the electrical resistivity (or conductivity) of the organic material, and the variable RH + t. If time-to-failure is a result of total number of coulombs conducted through the organic material, then the correlation of resistivity versus RH + t is synonymous with the empirical correlation of time-to-failure versus RH + t.

  4. Evidence that Arrhenius high-temperature aging behavior for an EPDM o-ring does not extrapolate to lower temperatures

    SciTech Connect

    Gillen, K.T.; Wise, J.; Celina, M.; Clough, R.L.

    1997-09-01

    Because of the need to significantly extend the lifetimes of weapons, and because of potential implications of environmental O-ring failure on degradation of critical internal weapon components, the authors have been working on improved methods of predicting and verifying O-ring lifetimes. In this report, they highlight the successful testing of a new predictive method for deriving more confident lifetime extrapolations. This method involves ultrasensitive oxygen consumption measurements. The material studied is an EPDM formulation use for the environmental O-ring the W88. Conventional oven aging (155 C to 111 C) was done on compression molded sheet material; periodically, samples were removed from the ovens and subjected to various measurements, including ultimate tensile elongation, density and modulus profiles. Compression stress relaxation (CSR) measurements were made at 125 C and 111 C on disc shaped samples (12.7 mm diameter by 6 mm thick) using a Shawbury Wallace Compression Stress Relaxometer MK 2. Oxygen consumption measurements were made versus time, at temperatures ranging from 160 C to 52 C, using chromatographic quantification of the change in oxygen content caused by reaction with the EPDM material in sealed containers.

  5. Role of initial state and final quench temperature on aging properties in phase-ordering kinetics

    NASA Astrophysics Data System (ADS)

    Corberi, Federico; Villavicencio-Sanchez, Rodrigo

    2016-05-01

    We study numerically the two-dimensional Ising model with nonconserved dynamics quenched from an initial equilibrium state at the temperature Ti≥Tc to a final temperature Tf below the critical one. By considering processes initiating both from a disordered state at infinite temperature Ti=∞ and from the critical configurations at Ti=Tc and spanning the range of final temperatures Tf∈[0 ,Tc[ we elucidate the role played by Ti and Tf on the aging properties and, in particular, on the behavior of the autocorrelation C and of the integrated response function χ . Our results show that for any choice of Tf, while the autocorrelation function exponent λC takes a markedly different value for Ti=∞ [λC(Ti=∞ ) ≃5 /4 ] or Ti=Tc [λC(Ti=Tc) ≃1 /8 ] the response function exponents are unchanged. Supported by the outcome of the analytical solution of the solvable spherical model we interpret this fact as due to the different contributions provided to autocorrelation and response by the large-scale properties of the system. As changing Tf is considered, although this is expected to play no role in the large-scale and long-time properties of the system, we show important effects on the quantitative behavior of χ . In particular, data for quenches to Tf=0 are consistent with a value of the response function exponent λχ=1/2 λC(Ti=∞ ) =5 /8 different from the one [λχ∈(0.5 -0.56 ) ] found in a wealth of previous numerical determinations in quenches to finite final temperatures. This is interpreted as due to important preasymptotic corrections associated to Tf>0 .

  6. Burial and thermal history of the central Appalachian basin, based on three 2-D models of Ohio, Pennsylvania, and West Virginia

    USGS Publications Warehouse

    Rowan, Elisabeth L.

    2006-01-01

    Introduction: Three regional-scale, cross sectional (2-D) burial and thermal history models are presented for the central Appalachian basin based on the detailed geologic cross sections of Ryder and others (2004), Crangle and others (2005), and Ryder, R.T., written communication. The models integrate the available thermal and geologic information to constrain the burial, uplift, and erosion history of the region. The models are restricted to the relatively undeformed part of the basin and extend from the Rome trough in West Virginia and Pennsylvania northwestward to the Findlay arch in Ohio. This study expands the scope of previous work by Rowan and others (2004) which presented a preliminary burial/thermal history model for a cross section (E-E') through West Virginia and Ohio. In the current study, the burial/thermal history model for E-E' is revised, and integrated with results of two additional cross sectional models (D-D' and C-C'). The burial/thermal history models provide calculated thermal maturity (Ro%) values for the entire stratigraphic sequence, including hydrocarbon source rocks, along each of the three cross sections. In contrast, the Ro and conodont CAI data available in the literature are sparse and limited to specific stratigraphic intervals. The burial/thermal history models also provide the regional temperature and pressure framework that is needed to model hydrocarbon migration.

  7. Effects of Finish Cooling Temperature on Tensile Properties After Thermal Aging of Strain-Based API X60 Linepipe Steels

    NASA Astrophysics Data System (ADS)

    Sung, Hyo Kyung; Lee, Dong Ho; Shin, Sang Yong; Lee, Sunghak; Ro, Yunjo; Lee, Chang Sun; Hwang, Byoungchul

    2015-09-01

    Two types of strain-based American Petroleum Institute (API) X60 linepipe steels were fabricated at two finish cooling temperatures, 673 K and 723 K (400 °C and 450 °C), and the effects of the finish cooling temperatures on the tensile properties after thermal aging were investigated. The strain-based API X60 linepipe steels consisted mainly of polygonal ferrite (PF) or quasi-polygonal ferrite and the volume fraction of acicular ferrite increased with the increasing finish cooling temperature. In contrast, the volume fractions of bainitic ferrite (BF) and secondary phases decreased. The tensile properties before and after thermal aging at 473 K and 523 K (200 °C and 250 °C) were measured. The yield strength, ultimate tensile strength, and yield ratio increased with the increasing thermal aging temperature. The strain hardening rate in the steel fabricated at the higher finish cooling temperature decreased rapidly after thermal aging, probably due to the Cottrell atmosphere, whereas the strain hardening rate in the steel fabricated at the lower finish cooling temperature changed slightly after thermal aging. The uniform elongation and total elongation decreased with increasing thermal aging temperature, probably due to the interactions between carbon atoms and dislocations. The uniform elongation decreased rapidly with the decreasing volume fractions of BF and martensite and secondary phases. The yield ratio increased with the increasing thermal aging temperature, whereas the strain hardening exponent decreased. The strain hardening exponent of PL steel decreased rapidly after thermal aging because of the large number of mobile dislocations between PF and BF or martensite or secondary phases.

  8. Aging.

    PubMed

    Park, Dong Choon; Yeo, Seung Geun

    2013-09-01

    Aging is initiated based on genetic and environmental factors that operate from the time of birth of organisms. Aging induces physiological phenomena such as reduction of cell counts, deterioration of tissue proteins, tissue atrophy, a decrease of the metabolic rate, reduction of body fluids, and calcium metabolism abnormalities, with final progression onto pathological aging. Despite the efforts from many researchers, the progression and the mechanisms of aging are not clearly understood yet. Therefore, the authors would like to introduce several theories which have gained attentions among the published theories up to date; genetic program theory, wear-and-tear theory, telomere theory, endocrine theory, DNA damage hypothesis, error catastrophe theory, the rate of living theory, mitochondrial theory, and free radical theory. Although there have been many studies that have tried to prevent aging and prolong life, here we introduce a couple of theories which have been proven more or less; food, exercise, and diet restriction. PMID:24653904

  9. Aging

    PubMed Central

    Park, Dong Choon

    2013-01-01

    Aging is initiated based on genetic and environmental factors that operate from the time of birth of organisms. Aging induces physiological phenomena such as reduction of cell counts, deterioration of tissue proteins, tissue atrophy, a decrease of the metabolic rate, reduction of body fluids, and calcium metabolism abnormalities, with final progression onto pathological aging. Despite the efforts from many researchers, the progression and the mechanisms of aging are not clearly understood yet. Therefore, the authors would like to introduce several theories which have gained attentions among the published theories up to date; genetic program theory, wear-and-tear theory, telomere theory, endocrine theory, DNA damage hypothesis, error catastrophe theory, the rate of living theory, mitochondrial theory, and free radical theory. Although there have been many studies that have tried to prevent aging and prolong life, here we introduce a couple of theories which have been proven more or less; food, exercise, and diet restriction. PMID:24653904

  10. Effects of aging temperature on G-phase precipitation and ferrite-phase decomposition in duplex stainless steel

    NASA Astrophysics Data System (ADS)

    Hamaoka, T.; Nomoto, A.; Nishida, K.; Dohi, K.; Soneda, N.

    2012-12-01

    G-phase precipitation and ferrite-phase decomposition in a cast duplex stainless steel (DSS) aged at 623-723 K for up to 8000 h were investigated using atom probe tomography (APT). Large sample volume was observed in every APT experiment, which yielded significantly statistical results. The number density of G-phase precipitates tended to be high and their sizes were small at lower aging temperatures. G-phase precipitates grew during prolonged isothermal aging. The concentrations of nickel, silicon, manganese and molybdenum in G-phase precipitates tended to increase as the precipitates grew. Heterogeneous distributions of alloying elements within G-phase precipitates were observed. An interesting positional relationship of G-phase precipitates with dislocations was revealed. Regarding the ferrite-phase decomposition, local chromium concentrations in the ferrite phase varied fast at higher aging temperatures. Good correlation between the variation of local chromium concentrations and aging conditions was revealed, which indicates that the variation can be estimated for arbitrary aging conditions. Representative distances between chromium-enriched and chromium-diluted regions were long at higher aging temperatures. Time exponent of the representative distances of ferrite-phase decomposition as well as the size of G-phase precipitates increased with aging temperatures.

  11. New insights into Eastern Beringian mortuary behavior: A terminal Pleistocene double infant burial at Upward Sun River

    PubMed Central

    Potter, Ben A.; Irish, Joel D.; Reuther, Joshua D.; McKinney, Holly J.

    2014-01-01

    Here we report on the discovery of two infant burials dating to ∼11,500 calibrated years (cal) B.P. at the Upward Sun River site in central Alaska. The infants were interred in a pit feature with associated organic and lithic grave goods, including the earliest known North American hafted bifaces with decorated antler foreshafts. Skeletal and dental analyses indicate that Individual 1 died shortly after birth and Individual 2 was a late-term fetus, making these the youngest-aged late Pleistocene individuals known for the Americas and the only known prenate, offering, to our knowledge, the first opportunity to explore mortuary treatment of the youngest members of a terminal Pleistocene North American population. This burial was situated ∼40 cm directly below a cremated 3-y-old child previously discovered in association with a central hearth of a residential feature. The burial and cremation are contemporaneous, and differences in body orientation, treatment, and associated grave goods within a single feature and evidence for residential occupation between burial episodes indicate novel mortuary behaviors. The human remains, grave goods, and associated fauna provide rare direct data on organic technology, economy, seasonality of residential occupations, and infant/child mortality of terminal Pleistocene Beringians. PMID:25385599

  12. New insights into Eastern Beringian mortuary behavior: a terminal Pleistocene double infant burial at Upward Sun River.

    PubMed

    Potter, Ben A; Irish, Joel D; Reuther, Joshua D; McKinney, Holly J

    2014-12-01

    Here we report on the discovery of two infant burials dating to ∼11,500 calibrated years (cal) B.P. at the Upward Sun River site in central Alaska. The infants were interred in a pit feature with associated organic and lithic grave goods, including the earliest known North American hafted bifaces with decorated antler foreshafts. Skeletal and dental analyses indicate that Individual 1 died shortly after birth and Individual 2 was a late-term fetus, making these the youngest-aged late Pleistocene individuals known for the Americas and the only known prenate, offering, to our knowledge, the first opportunity to explore mortuary treatment of the youngest members of a terminal Pleistocene North American population. This burial was situated ∼40 cm directly below a cremated 3-y-old child previously discovered in association with a central hearth of a residential feature. The burial and cremation are contemporaneous, and differences in body orientation, treatment, and associated grave goods within a single feature and evidence for residential occupation between burial episodes indicate novel mortuary behaviors. The human remains, grave goods, and associated fauna provide rare direct data on organic technology, economy, seasonality of residential occupations, and infant/child mortality of terminal Pleistocene Beringians. PMID:25385599

  13. Influence of Anchoring on Burial Depth of Submarine Pipelines

    PubMed Central

    Zhuang, Yuan; Li, Yang; Su, Wei

    2016-01-01

    Since the beginning of the twenty-first century, there has been widespread construction of submarine oil-gas transmission pipelines due to an increase in offshore oil exploration. Vessel anchoring operations are causing more damage to submarine pipelines due to shipping transportation also increasing. Therefore, it is essential that the influence of anchoring on the required burial depth of submarine pipelines is determined. In this paper, mathematical models for ordinary anchoring and emergency anchoring have been established to derive an anchor impact energy equation for each condition. The required effective burial depth for submarine pipelines has then been calculated via an energy absorption equation for the protection layer covering the submarine pipelines. Finally, the results of the model calculation have been verified by accident case analysis, and the impact of the anchoring height, anchoring water depth and the anchor weight on the required burial depth of submarine pipelines has been further analyzed. PMID:27166952

  14. Influence of Anchoring on Burial Depth of Submarine Pipelines.

    PubMed

    Zhuang, Yuan; Li, Yang; Su, Wei

    2016-01-01

    Since the beginning of the twenty-first century, there has been widespread construction of submarine oil-gas transmission pipelines due to an increase in offshore oil exploration. Vessel anchoring operations are causing more damage to submarine pipelines due to shipping transportation also increasing. Therefore, it is essential that the influence of anchoring on the required burial depth of submarine pipelines is determined. In this paper, mathematical models for ordinary anchoring and emergency anchoring have been established to derive an anchor impact energy equation for each condition. The required effective burial depth for submarine pipelines has then been calculated via an energy absorption equation for the protection layer covering the submarine pipelines. Finally, the results of the model calculation have been verified by accident case analysis, and the impact of the anchoring height, anchoring water depth and the anchor weight on the required burial depth of submarine pipelines has been further analyzed. PMID:27166952

  15. Effects of Resveratrol on Daily Rhythms of Locomotor Activity and Body Temperature in Young and Aged Grey Mouse Lemurs

    PubMed Central

    Dal-Pan, Alexandre; Languille, Solène; Aujard, Fabienne

    2013-01-01

    In several species, resveratrol, a polyphenolic compound, activates sirtuin proteins implicated in the regulation of energy balance and biological clock processes. To demonstrate the effect of resveratrol on clock function in an aged primate, young and aged mouse lemurs (Microcebus murinus) were studied over a 4-week dietary supplementation with resveratrol. Spontaneous locomotor activity and daily variations in body temperature were continuously recorded. Reduction in locomotor activity onset and changes in body temperature rhythm in resveratrol-supplemented aged animals suggest an improved synchronisation on the light-dark cycle. Resveratrol could be a good candidate to restore the circadian rhythms in the elderly. PMID:23983895

  16. Room temperature aging of Narmco 5208 carbon-epoxy prepreg. I. Physicochemical characterization

    SciTech Connect

    Cole, K.C.; Noel, D.; Hechler, J.J.; Chouliotis, A.; Overbury, K.C. )

    1989-06-01

    Data are presented on physicochemical tests carried out on room-temperature aged samples of a commercially available carbon-epoxy composite prepreg system. The analytical methods used included Fourier transform IR (FTIR) spectroscopy, reverse-phase liquid chromatography (RPLC), high-speed RPLC, high-performance size-exclusion chromatography, differential scanning calorimetry and thermogravimetry, and pyrolysis/gas chromatography. All data indicated significant changes in these samples due to aging, with the most sensitive indices being those of FTIR and RPLC procedures. Results indicate that the number of unreacted epoxy groups decreased steadily at a rate of 0.34 percent per day, based on the initial amount, and the number of free amine-hardener molecules decreased at a rate of 1.05 percent per day. The amount of initial epoxy-amine reaction product increased significantly over the first 30 days, but then declined, due to further reactions of these to give higher-molecular-weight products. 23 refs.

  17. Lithium plating in a commercial lithium-ion battery - A low-temperature aging study

    NASA Astrophysics Data System (ADS)

    Petzl, Mathias; Kasper, Michael; Danzer, Michael A.

    2015-02-01

    The formation of metallic lithium on the negative graphite electrode in a lithium-ion (Li-ion) battery, also known as lithium plating, leads to severe performance degradation and may also affect the cell safety. This study is focused on the nondestructive characterization of the aging behavior during long-term cycling at plating conditions, i.e. low temperature and high charge rate. A commercial graphite/LiFePO4 Li-ion battery is investigated in order to elucidate the aging effects of lithium plating for real-world purposes. It is shown that lithium plating can be observed as a loss of cyclable lithium which affects the capacity balance of the electrodes. In this way, lithium plating counteracts its own occurrence during prolonged cycling. The capacity losses due to lithium plating are therefore decreasing at higher cycle numbers and the capacity retention curve exhibits an inflection point. It is further shown that the observed capacity fade is partly reversible. Electrochemical impedance spectroscopy (EIS) reveals a significant increase of the ohmic cell resistance due to electrolyte consumption during surface film formation on the plated lithium. Additional cell opening provides important quantitative information regarding the thickness of the lithium layer and the corresponding mass of the plated lithium.

  18. Controls on biogenic silica burial in the Southern Ocean

    NASA Astrophysics Data System (ADS)

    Chase, Zanna; Kohfeld, Karen E.; Matsumoto, Katsumi

    2015-10-01

    Understanding the controls on opal export in the Southern Ocean can inform both the prediction of how the leakage of silicic acid from the Southern Ocean responds to climate and the interpretation of paleo-proxies. We have compiled a database of 185 230Thorium-normalized opal burial rates and 493 opal concentration measurements in Southern Ocean sediments and matched these with environmental climatologies. By subdividing the Southern Ocean on the basis of oceanographic regions and interpolating the opal burial rates, we estimate a total biogenic Si burial south of 40°S of 2.3 ± 1.0 Tmol Si yr-1. In both the seasonally ice-covered and permanently ice-free regions we can explain 73% of opal burial variability from surface ocean properties. Where sea ice is present for at least part of the year, the length of the ice-free season determines the upper limit of opal burial in the underlying sediments. In the ice-free regions of the Southern Ocean, the supply of silicic acid through winter mixing is the most important factor. Our results do not support a strong role of iron in controlling opal burial. We do however find that satellite-derived net primary production increases with increasing (modeled) dust delivery. These findings support the decoupling between carbon and opal fluxes in the Southern Ocean. When corrected for opal dissolution, the observed opal fluxes are in reasonable agreement with fluxes simulated using an ocean biogeochemical model. However, the results suggest current preservation algorithms for opal could be improved by incorporating the composition of particle flux, not only its magnitude.

  19. Evolution of stocks and massifs from burial of salt sheets, continental slope, northern Gulf of Mexico

    SciTech Connect

    Seni, S.J. )

    1991-03-01

    Salt structures in a 4000-km{sup 2} region of the continental slope, the northeast Green Canyon area, include stocks, massifs, remnant structures, and an allochthonous sheet. Salt-withdrawal basins include typical semicircular basins and an extensive linear trough that is largely salt-free. Counterregional growth faults truncate the landward margin of salt sheets that extend 30-50 km to the Sigsbee Escarpment. The withdrawal basins, stocks, and massifs occur within a large graben between an east-northeast-trending landward zone of shelf-margin growth faults and a parallel trend of counterregional growth faults located 48-64 km basinward. The graben formed by extension and subsidence as burial of the updip portion of a thick salt sheet produced massifs and stocks by downbuilding. Differential loading segmented the updip margin of the salt sheet into stocks and massifs separated by salt-withdrawal basins. Initially, low-relief structures evolved by trap-door growth as half-graben basins buried the salt sheet. Remnant-salt structures and a turtle-structure anticline overlay a salt-weld disconformity in sediments formerly separated by a salt sheet. Age of sediments below the weld is inferred to be be late Miocene to early Pliocene (4.6-5.3 Ma); age of sediments above the weld is late Pliocene (2.8-3.5 Ma). The missing interval of time (1-2.5 Ma) is the duration between emplacement of the salt sheet and burial of the sheet. Sheet extrusion began in the late Miocene to early Pliocene, and sheet burial began in the late Pliocene in the area of the submarine trough to early Pleistocene in the area of the massifs.

  20. Alternatives to the burial of low-level radioactive waste

    SciTech Connect

    Price, J. Mark

    2007-07-01

    Available in abstract form only. Full text of publication follows: The approach for management of LLRW in different countries has evolved differently due to many factors such as culture and public sentiment, systems of government, public policy, and geography. There are also various methods to disposition LLRW including but not limited to: - Long term statutes and unconditional or conditional release of material, - Direct Burial, - Treatment (Processing) {yields} Burial, - Treatment {yields} Unconditional Release, - Recycle for Unconditional Release or Reuse Within Any Industry, - Controlled Recycle within Nuclear Industry. (author)

  1. Grief and burial in the American Southwest: the role of evolutionary theory in the interpretation of mortuary remains.

    PubMed

    MacDonald, D H

    2001-10-01

    Evolutionary theory, in consort with Marxism and processualism, provides new insights into the interpretation of grave-good variation. Processual interpretations of burial sites in the American Southwest cite age, sex, or social rank as the main determinants of burial-good variation. Marxist theorists suggest that mortuary ritual mediates social tension between an egalitarian mindset and an existing social inequality. Evolutionary theory provides a supplementary explanatory framework. Recent studies guided by kin-selection theory suggest that humans grieve more for individuals of high reproductive value and genetic relatedness. Ethnographic examples also show that individuals mourn more intensively and, thus, place more social emphasis on burials of individuals of highest reproductive value (young adults). Analysis of grave goods from La Ciudad, a Hohokam site in the American Southwest, supports the hypothesis that labor value, reproductive value, and grief contributed to grave-good differentiation. At La Ciudad, individuals between the ages of 10 and 20 possessed more and higher-quality grave goods on average than any other age group. Grief at the loss of a young adult of high reproductive and labor value may facilitate explanation of mortuary variation at La Ciudad, as well as other sites in the greater Southwest and beyond. PMID:20043376

  2. A 150 year record of inter-annual climate variability and organic carbon burial in Santa Monica and Santa Barbara Basins

    SciTech Connect

    Hagadorn, J.W.; Stott, L.D.; Sinha, A.; Rincon, M. . Dept. of Geological Sciences); Schimmelmann, A. . Scripps Inst. of Oceanography)

    1992-01-01

    Stable isotopic measurements were conducted on total organic carbon (TOC) and fossil planktonic foraminifera in laminated sediments collected from Santa Monica and Santa Barbara Basins, California Borderland, in order to investigate relationships between climatic variability and organic carbon burial. These data currently provide biannual sample resolution back to 1750 AD. During the past 150 years, there has been a positive covariance between the carbon isotopic composition of fossil planktonic foraminifera and of TOC. Periods of increased delta C-13 of TOC and foraminifera correspond to higher organic carbon burial in Santa Monica and Santa Barbara Basins. When combined, these patterns are interpreted as variation in productivity within the basins. Isotopic variability in TOC and planktonic foraminifera is significantly higher prior to 1900 AD. Although spring sea surface temperatures were also significantly more variable during this period, the authors do not recognize a systematic relationship between temperature and organic carbon burial. Spectral analysis of isotopic compositions of fossil foraminifera calcite, TOC, organic carbon burial and lamination frequency in the sediments reveal distinct spectral peaks at 5 and 7.7 years, corresponding to ENSO/El Nino frequencies. Additional spectral peaks occur at 19 and 20 years. Previous time series analyses of tree ring width records indicate similar decadal-scale frequencies and suggest a possible link to solar and/or lunar nodal tidal cycles. While these initial results suggest a relationship between climate-cyclicity, primary productivity and organic carbon burial, the phase relationship cannot be deciphered from this preliminary data set.

  3. The Combined Influence of Molecular Weight and Temperature on the Aging and Viscoelastic Response of a Glassy Thermoplastic Polyimide

    NASA Technical Reports Server (NTRS)

    Nicholson, Lee M.; Whitley, Karen S.; Gates, Thomas S.

    2000-01-01

    The effect of molecular weight on the viscoelastic performance of an advanced polymer (LaRC-SI) was investigated through the use of creep compliance tests. Testing consisted of short-term isothermal creep and recovery with the creep segments performed under constant load. The tests were conducted at three temperatures below the glass transition temperature of five materials of different molecular weight. Through the use of time-aging-time superposition procedures, the material constants, material master curves and aging-related parameters were evaluated at each temperature for a given molecular weight. The time-temperature superposition technique helped to describe the effect of temperature on the timescale of the viscoelastic response of each molecular weight. It was shown that the low molecular weight materials have higher creep compliance and creep rate, and are more sensitive to temperature than the high molecular weight materials. Furthermore, a critical molecular weight transition was observed to occur at a weight-average molecular weight of M (bar) (sub w) 25000 g/mol below which, the temperature sensitivity of the time-temperature superposition shift factor increases rapidly. The short-term creep compliance data were used in association with Struik's effective time theory to predict the long-term creep compliance behavior for the different molecular weights. At long timescales, physical aging serves to significantly decrease the creep compliance and creep rate of all the materials tested.

  4. Low temperature aging mechanism identification and lithium deposition in a large format lithium iron phosphate battery for different charge profiles

    NASA Astrophysics Data System (ADS)

    Ouyang, Minggao; Chu, Zhengyu; Lu, Languang; Li, Jianqiu; Han, Xuebing; Feng, Xuning; Liu, Guangming

    2015-07-01

    Charging procedures at low temperatures severely shorten the cycle life of lithium ion batteries due to lithium deposition on the negative electrode. In this paper, cycle life tests are conducted to reveal the influence of the charging current rate and the cut-off voltage limit on the aging mechanisms of a large format LiFePO4 battery at a low temperature (-10 °C). The capacity degradation rates accelerate rapidly after the charging current reaches 0.25 C or the cut-off voltage reaches 3.55 V. Therefore the scheduled current and voltage during low-temperature charging should be reconsidered to avoid capacity degradation. Lithium deposition contributes to low-temperature aging mechanisms, as something needle-like which might be deposited lithium is observed on the surface of the negative electrode after disassembling the aged battery cell. To confirm our explanation, incremental capacity analysis (ICA) is performed to identify the characteristics of the lithium deposition induced battery aging mechanisms. Furthermore, the aging mechanism is quantified using a mechanistic model, whose parameters are estimated with the particle swarm optimization algorithm (PSO). The loss of reversible lithium originating from secondary SEI formation and dead lithium is confirmed as the cause of the aging.

  5. Calorie restriction lowers body temperature in rhesus monkeys, consistent with a postulated anti-aging mechanism in rodents.

    PubMed Central

    Lane, M A; Baer, D J; Rumpler, W V; Weindruch, R; Ingram, D K; Tilmont, E M; Cutler, R G; Roth, G S

    1996-01-01

    Many studies of caloric restriction (CR) in rodents and lower animals indicate that this nutritional manipulation retards aging processes, as evidenced by increased longevity, reduced pathology, and maintenance of physiological function in a more youthful state. The anti-aging effects of CR are believed to relate, at least in part, to changes in energy metabolism. We are attempting to determine whether similar effects occur in response to CR in nonhuman primates. Core (rectal) body temperature decreased progressively with age from 2 to 30 years in rhesus monkeys fed ad lib (controls) and is reduced by approximately 0.5 degrees C in age-matched monkeys subjected to 6 years of a 30% reduction in caloric intake. A short-term (1 month) 30% restriction of 2.5-year-old monkeys lowered subcutaneous body temperature by 1.0 degrees C. Indirect calorimetry showed that 24-hr energy expenditure was reduced by approximately 24% during short-term CR. The temporal association between reduced body temperature and energy expenditure suggests that reductions in body temperature relate to the induction of an energy conservation mechanism during CR. These reductions in body temperature and energy expenditure are consistent with findings in rodent studies in which aging rate was retarded by CR, now strengthening the possibility that CR may exert beneficial effects in primates analogous to those observed in rodents. PMID:8633033

  6. 38 CFR 3.1704 - Burial allowance based on service-connected death.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... under § 3.1709, Transportation expenses for burial in a national cemetery; and (2) VA may pay the plot or interment allowance for burial in a State veterans cemetery under § 3.1707(a), Plot or...

  7. Organic carbon burial efficiency in a large tropical hydroelectric reservoir

    NASA Astrophysics Data System (ADS)

    Mendonça, R.; Kosten, S.; Sobek, S.; Cardoso, S. J.; Figueiredo-Barros, M. P.; Estrada, C. H. D.; Roland, F.

    2015-11-01

    Hydroelectric reservoirs bury significant amounts of organic carbon (OC) in their sediments. Many reservoirs are characterized by high sedimentation rates, low oxygen concentrations in bottom water, and a high share of terrestrially derived OC, and all of these factors have been linked to a high efficiency of OC burial. However, investigations of OC burial efficiency (OCBE, i.e. the ratio between OC buried and deposited) in reservoirs is limited to a few studies, none of which include spatially resolved analyses. In this study we determined the spatial variation in OCBE in a large tropical reservoir and related it to sediment characteristics. Our results show that the sediment accumulation rate explains up to 92 % of the spatial variability in OCBE, outweighing the effect of other variables, such as OC source and oxygen exposure time. OCBE at the pelagic sites varied from 48 to 86 % (mean 67 %) and decreased towards the dam. At the margins, OCBE was lower (9 to 17 %) due to the low sediment accumulation in shallow areas. Our data show that the variability in OCBE both along the rivers-dam and the margin-pelagic axes must be considered in whole-reservoir assessments. Combining these results with a spatially resolved assessment of sediment accumulation and OC burial in the studied reservoir, we estimated a whole-basin OC burial efficiency of 57 %. Being the first whole-basin assessment of OCBE in a reservoir, these results suggest that reservoirs may bury OC more efficiently than natural lakes.

  8. 40 CFR 229.1 - Burial at sea.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Burial at sea. 229.1 Section 229.1 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING GENERAL PERMITS § 229.1... materials which are readily de-com-pos-a-ble in the marine environment may be disposed of under the...

  9. Organic carbon burial efficiency in a subtropical hydroelectric reservoir

    NASA Astrophysics Data System (ADS)

    Mendonça, Raquel; Kosten, Sarian; Sobek, Sebastian; Jaqueline Cardoso, Simone; Figueiredo-Barros, Marcos Paulo; Henrique Duque Estrada, Carlos; Roland, Fábio

    2016-06-01

    Hydroelectric reservoirs bury significant amounts of organic carbon (OC) in their sediments. Many reservoirs are characterized by high sedimentation rates, low oxygen concentrations in bottom water and a high share of terrestrially derived OC, and all of these factors have been linked to a high efficiency of OC burial. However, investigations of OC burial efficiency (OCBE, i.e., the ratio between buried and deposited OC) in reservoirs are limited to a few studies, none of which include spatially resolved analyses. In this study we determined the spatial variation in OCBE in a large subtropical reservoir and related it to sediment characteristics. Our results show that the sediment accumulation rate explains up to 92 % of the spatial variability in OCBE, outweighing the effect of other variables, such as OC source and oxygen exposure time. OCBE at the pelagic sites varied from 48 to 86 % (mean 67 %) and decreased towards the dam. At the margins, OCBE was lower (9-17 %) due to the low sediment accumulation in shallow areas. Our data show that the variability in OCBE both along the rivers-dam and the margin-pelagic axes must be considered in whole-reservoir assessments. Combining these results with a spatially resolved assessment of sediment accumulation and OC burial in the studied reservoir, we estimated a spatially resolved mean OC burial efficiency of 57 %. Being the first assessment of OCBE with such a high spatial resolution in a reservoir, these results suggest that reservoirs may bury OC more efficiently than natural lakes.

  10. Cleanup Verification Package for the 118-F-6 Burial Ground

    SciTech Connect

    H. M. Sulloway

    2008-10-02

    This cleanup verification package documents completion of remedial action for the 118-F-6 Burial Ground located in the 100-FR-2 Operable Unit of the 100-F Area on the Hanford Site. The trenches received waste from the 100-F Experimental Animal Farm, including animal manure, animal carcasses, laboratory waste, plastic, cardboard, metal, and concrete debris as well as a railroad tank car.

  11. Interactive effects of biochar ageing in soils related to feedstock, pyrolysis temperature, and historic charcoal production.

    NASA Astrophysics Data System (ADS)

    Heitkötter, Julian; Marschner, Bernd

    2015-04-01

    Biochar is suggested for soil amelioration and carbon sequestration, based on its assumed role as the key factor for the long-term fertility of Terra preta soils. Several studies have shown that certain biochar properties can undergo changes through ageing processes, especially regarding charge characteristics. However, only a few studies determined the changes of different biochars under the same incubation conditions and in different soils. The objective of this study was to characterize the changes of pine chip (PC)- and corn digestate (CD)-derived biochars pyrolyzed at 400 or 600 °C during 100 days of laboratory incubation in a historical kiln soil and an adjacent control soil. Separation between soil and biochar was ensured by using mesh bags. Especially, changes in charge characteristics depended on initial biochar properties affected by feedstock and pyrolysis temperature and on soil properties affected by historic charcoal production. While the cation exchange capacity (CEC) markedly increased for both CD biochars during incubation, PC biochars showed no or only slight increases in CEC. Corresponding to the changes in CEC, ageing of biochars also increased the amount of acid functional groups with increases being in average about 2-fold higher in CD biochars than in PC biochars. Further and in contrast to other studies, the surface areas of biochars increased during ageing, likely due to ash leaching and degradation of tar residues. Changes in CEC and surface acidity of CD biochars were more pronounced after incubation in the control soil, while surface area increase was higher in the kiln soil. Since the two acidic forest soils used in this this study did not greatly differ in physical or chemical properties, the main process for inducing these differences in the buried biochar most likely is related to the differences in dissolved organic carbon (DOC). Although the kiln soil contained about 50% more soil organic carbon due to the presence of charcoal

  12. Deep-burial diagenesis: Its implications for vertical movements of the crust, uplift of the lithosphere and isostatic unroofing—A review

    NASA Astrophysics Data System (ADS)

    Friedman, Gerald M.

    1987-03-01

    Various techniques of study of strata exposed at the surface in undeformed areas of the Appalachian Basin and Ozark Done, imply that these strata have been heated to temperatures that suggest a former great depth of burial. The data reveal that the strata have been much more deeply buried than previously thought. If such former deep burial has taken place, then subsequent uplift and erosion must also have taken place to bring these formerly deeply buried strata to the present land surface. Unexpectedly large amounts of uplift and erosion, ranging from 4.3 to 7 km, have re-exposed these formerly deeply buried rocks. This leads to the surprising conclusion that isostatic unroofing has stripped off thick sections of strata whose presence was previously unsuspected. Therefore, the lithosphere, in its isostatic unroofing of thick sequences of sedimentary strata, has undergone much larger vertical motions than many geologists had previously estimated. Case histories in this review include strata of the Silurian of the Northern Appalachian Basin and of the Ordovician of the Ozark Dome, which reached interpreted maximum burial depths of 5 and 4.3 km, respectively; Devonian strata in the Catskill Mountains of New York imply a former depth of burial of ˜ 6.5 km. Lower Ordovician carbonate sequences of the Northern Appalachian Basin imply a depth of burial in excess of 7 km; Middle Ordovician strata from the same basin signify a depth of burial of approximately 5 km; and Devonian strata, a paleodepth of 4.5-5 km. Such former great depths of burial of undeformed strata, which are now exposed at the surface, reflect large-scale vertical movements of the crust and uplift of the lithosphere. These drastic changes represent isostatic unroofing with widespread implications for paleogeography of a kind unrecognized at present.

  13. Effect of Thermal Aging on Ductile-Brittle Transition Temperature of Modified 9Cr-1Mo Steel Evaluated with Reference Temperature Approach Under Dynamic Loading Condition

    NASA Astrophysics Data System (ADS)

    Sathyanarayanan, S.; Basu, Joysurya; Moitra, A.; Sasikala, G.; Singh, V.

    2013-05-01

    The effect of thermal aging on the ductile-brittle transition behavior has been assessed for a modified 9Cr-1Mo steel (P91) using the reference temperature approach under dynamic loading condition ( T {0/dy}). The steel in normalized and tempered (NT) condition and in different levels of subsequent cold work (CW) was subjected to thermal aging at temperatures of 873 K and 923 K (600 °C and 650 °C) for 5000 and 10,000 hours. For the NT and all the cold work conditions of the starting material, a drastic increase in T {0/dy} has been noticed after aging at 923 K (650 °C) for 10,000 h. A moderate increase was observed for the NT steel aged at 873 K (600 °C) for 5000 hours and for the 10 pct CW steel aged at 873 K (600 °C) for 10,000 h. A detailed transmission electron microscope (TEM) study of the embrittled materials aged at 923 K (650 °C)/10,000 hours and 873 K (600 °C)/10,000 hours has indicated presence of hexagonal Laves phase of Fe2(Mo,Nb) type with different size and spatial distributions. The increase in the T {0/dy} is attributed to the embrittling effect of a network of Laves phase precipitates along the grain boundaries.

  14. Mechanical properties and microstructure of 6061 aluminum alloy severely deformed by ARB process and subsequently aged at low temperatures

    NASA Astrophysics Data System (ADS)

    Terada, Daisuke; Kaneda, Yoma; Horita, Zenji; Matsuda, Kenji; Hirosawa, Shoichi; Tsuji, Nobuhiro

    2014-08-01

    In order to clarify the aging behavior in ultrafine grained (UFG) Al alloys, a commercial Al-Mg-Si alloy was severely deformed by accumulative roll-bonding (ARB) process and subsequently aged at 100°C or 170°C. The age-hardening behavior and microstructure change during aging were investigated. At 170 °C, age-hardening was observed in solution treated (ST) specimens, but solution-treated and ARB-processed specimens were not hardened by aging. On the other hand, the hardness of the both ST specimen and ARB-processed specimen increased by aging at 100°C. From TEM observation, it was found that the ARB- processed specimen had an ultrafine lamellar boundary structure and the structure was kept during aging at 170°C and 100°C. In the ST specimen aged at 170°C, fine precipitates were observed within coarse grains. In the specimen ARB-processed and subsequently aged at 170°C, coarser precipitates were observed within ultrafine grains and on grain boundaries. It was considered that the reason why the hardness of the specimens ARB-processed and subsequently aged did not increase was coarsening of precipitates. In the specimens aged at 100°C, obvious precipitates were not observed, but clusters Mg and Si seemed to form during the aging, leading to the increase in the hardness of the specimen. From the results, it was suggested that aging at low temperatures could improve mechanical properties of Al alloys through combining grain refinement and precipitation hardening.

  15. C-14 and temperature variation around and after AD 775 - after the Dark Age Grand Minimum

    NASA Astrophysics Data System (ADS)

    Neuhäuser, Ralph; Neuhäuser, Dagmar L.

    2016-04-01

    We have compiled an extensive catalog of aurora observations from the Far and Near East as well as Europe for the time from AD 550 to 845. From historic observations of aurorae and sunspots as well as the C-14 and Be-10 data, we can date the end of the Dark Age grand minimum to about AD 690; we see strong activity after this period. We can fix the solar activity Schwabe cycle maxima and minima in the 7th and 8th centuries.. The strong 14-C increase in data with 1-yr time resolution in the AD 770s (e.g. Miyake et al. 2012) is still a matter of debate, e.g. a solar super-flare. In the last three millennia, there were two more strong rapid rises in 14-C - around BC 671 and AD 1795. All three 14-C variations are embedded in similar evolution of solar activity, as we can show with various solar activity proxies; secular evolution of solar wind plays an important role. The rises of 14-C - within a few years each - can be explained by a sudden strong decrease in solar modulation potential leading to increased radioisotope production. The strong rises around AD 775 and 1795 are due to three effects: (i) very strong activity in the previous cycles (i.e. very low 14-C level), (ii) the declining phase of a very strong Schwabe cycle, and (iii) a phase of very weak activity after the strong 14-C rise - very short and/or weak cycle(s) like the suddenly starting Dalton minimum. In addition to arXiv:1503.01581 and arXiv:1508.06745, we also discuss the temperature depression and new quasi-annual 10-Be data. If a temperature depression right after AD 775 for a few decades can be confirmed, this would be fully consistent with our suggestion: reduced solar activity since AD 775 (for a few decades like in the Dalton minimum). Otherwise, one would not expect such a temperature depression after a solar super-flare.

  16. 76 FR 61148 - Proposed Information Collection (Application for United States Flag for Burial Purposes) Activity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-03

    ... AFFAIRS Proposed Information Collection (Application for United States Flag for Burial Purposes) Activity... comments on the information needed to determine eligibility for issuance of a burial flag for a deceased... information technology. Title: Application for United States Flag for Burial Purposes, VA Form 21-2008....

  17. 38 CFR 3.1600 - Payment of burial expenses of deceased veterans.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Payment of burial expenses of deceased veterans. 3.1600 Section 3.1600 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Burial Benefits § 3.1600 Payment of burial expenses of deceased veterans....

  18. Associations between Changes in City and Address Specific Temperature and QT Interval - The VA Normative Aging Study

    PubMed Central

    Mehta, Amar J.; Kloog, Itai; Zanobetti, Antonella; Coull, Brent A.; Sparrow, David; Vokonas, Pantel; Schwartz, Joel

    2014-01-01

    Background The underlying mechanisms of the association between ambient temperature and cardiovascular morbidity and mortality are not well understood, particularly for daily temperature variability. We evaluated if daily mean temperature and standard deviation of temperature was associated with heart rate-corrected QT interval (QTc) duration, a marker of ventricular repolarization in a prospective cohort of older men. Methods This longitudinal analysis included 487 older men participating in the VA Normative Aging Study with up to three visits between 2000–2008 (n = 743). We analyzed associations between QTc and moving averages (1–7, 14, 21, and 28 days) of the 24-hour mean and standard deviation of temperature as measured from a local weather monitor, and the 24-hour mean temperature estimated from a spatiotemporal prediction model, in time-varying linear mixed-effect regression. Effect modification by season, diabetes, coronary heart disease, obesity, and age was also evaluated. Results Higher mean temperature as measured from the local monitor, and estimated from the prediction model, was associated with longer QTc at moving averages of 21 and 28 days. Increased 24-hr standard deviation of temperature was associated with longer QTc at moving averages from 4 and up to 28 days; a 1.9°C interquartile range increase in 4-day moving average standard deviation of temperature was associated with a 2.8 msec (95%CI: 0.4, 5.2) longer QTc. Associations between 24-hr standard deviation of temperature and QTc were stronger in colder months, and in participants with diabetes and coronary heart disease. Conclusion/Significance In this sample of older men, elevated mean temperature was associated with longer QTc, and increased variability of temperature was associated with longer QTc, particularly during colder months and among individuals with diabetes and coronary heart disease. These findings may offer insight of an important underlying mechanism of temperature

  19. Emplacement, rapid burial, and exhumation of 90-Ma plutons in southeastern Alaska

    USGS Publications Warehouse

    Himmelberg, G.R.; Haeussler, P.J.; Brew, D.A.

    2004-01-01

    In southeastern Alaska, granodiorite-tonalite plutons of the Admiralty-Revillagigedo belt intruded the Jurassic-Cretaceous Gravina belt along the eastern side of the Alexander terrane around 90 Ma. These plutons postdate some deformation related to a major contractional event between the previously amalgamated Wrangellia and Alexander terranes and the previously accreted terranes of the North American margin. We studied the aureole mineral assemblages of these plutons near Petersburg, Alaska, determined pressure and temperature of equilibration, and examined structures that developed within and adjacent to these plutons. Parallelism of magmatic and submagmatic fabrics with fabrics in the country rock indicates synchroneity of pluton emplacement with regional deformation and suggests that magma transport to higher crustal levels was assisted by regional deformation. Replacement of andalusite by kyanite or sillimanite indicates crustal thickening soon after pluton emplacement. Regional structural analysis indicates the crustal thickening was accomplished by thrust burial. Thermobarometric analyses indicate the aureoles reached near-peak temperatures of 525 to 635 ??C at pressures of 570 to 630 MPa. Consideration of the rate of thermal decay of the aureoles suggests that burial was rapid and occurred at rates around 5 to 8 mm/year. Structural observations indicate there was contractional deformation before, during, and after emplacement of the 90-Ma plutons. Initial exhumation of the Admiralty-Revillagedo belt in the Petersburg area may have occurred along a thrust west of the pluton belt within the Gravina belt. ?? 2004 NRC Canada.

  20. Hydrology of the low-level radioactive solid waste burial site and vicinity near Barnwell, South Carolina

    USGS Publications Warehouse

    Cahill, James M.

    1982-01-01

    Geologic and hydrologic conditions at a burial site for low-level radioactive waste were studied, and migration of leachates from the buried waste into surrounding unconsolidated sediments were evaluated. The burial site and vicinity are underlain by a sequence of unconsolidated sediments of Late Cretaceous, Tertiary, and Quaternary age. These sediments are deposited over a graben which has been filled with sedimentary rocks of Triassic age. Hydraulic properties of the sediments beneath the burial site were determined by laboratory and field tests. Laboratory hydraulic conductivity values ranged from about 10^-7 to 10^-1 feet per day for the clayey sediments to nearly 22 feet per day for aquifer sands. Field aquifer tests indicate a transmissivity of about 22,000 feet squared per day for Cretaceous sediments and about 6,000 feet squared per day for Tertiary sediments. Aquifer tests indicate heterogeneity in the upper 200 feet of the Tertiary sediments. Water samples were analyzed from 51 wells, 5 streams, a Carolina bay, and rainfall at the burial site. The total dissolved solids of the ground water ranged from about 7 to 40 milligrams per liter in the upper clayey sediments to about 150 milligrams per liter in the water in the deeper calcareous sediments. The pH of the ground water ranges from 4.8 to 6.5. This slightly acidic water is corrosive to buried metal. Tritium activity greater than background was detected in sediment cores taken from drill holes adjacent to the burial trenches. High tritium activity occurred at depths above the trench floor. This indicates upward movement of water or vapor to the land surface. Tritium and organic constituents greater than background concentrations were observed in a monitoring well about 10 feet from a trench, indicating lateral migration of radionuclides from the buried waste. Traces of cobalt-60 and tritium greater than background activity were observed in sediment cores collected 5.8 feet beneath the trench floor at

  1. Clay mineral burial diagenesis: A case study from the Calabar flank of the Niger Delta

    NASA Astrophysics Data System (ADS)

    Braide, Sokari P.

    Detailed clay mineralogic and chemical analyses of Tertiary subsurface sediments of the Agbada and Akata Formations, from two wells on the Calabar Flank of the Niger Delta, have been systematically studied with a view to understanding clay mineral burial diagenesis. Five principal clay minerals, smectite, illite, kaolinite, chlorite and various proportions of mixed-layer illite/smectite were identified. Seven major oxides (SiO 2, Al 2O 3, MgO, Fe 2O 3, CaO, Na 2O, K 2O) were analysed for with an atomic absorption spectrophotometer, with a view to ascertain any depth related variations. The geothermal gradient of the two wells (Uruan-1 and Uda-1) was also calculated. The results appear to suggest a transformation from smectite to a mixed-layer illite/smectite (I/S) phase. The transformation first goes to a random I/S phase, and then to ordered I/S and back to random I/S, even though postulated conditions for a complete transformation to illite did exist. It would therefore seem, from this case study, that neither temperature nor the availability of potassium is the principal factor controlling the transformation. Kaolinite and chlorite distribution does not exhibit any systematic trend that could be related to burial diagenesis. These results provoked an extensive literature review on the subject, and key ideas discerned are summarized here. The prognosis? In the author's opinion, we still have a lot to learn about the factors that control the mechanics and reaction extent of clay mineral burial diagenesis.

  2. Antiquity of man in America indicated by radiometric dates on the Yuha burial site

    USGS Publications Warehouse

    Bischoff, J.L.; Merriam, R.; Childers, W.M.; Protsch, R.

    1976-01-01

    MUCH evidence suggests that man was present in the Western Hemisphere before 12,000 yr ago, but the case has remained less than conclusive 1. In some situations, the geological age of the site is reasonably well established but the association or nature of the artefacts is questionable2,3. In other cases, museum specimens of human bones dated by radiocarbon analysis of collagen lack desirable information concerning site location, geology, and stratigraphy even though the accuracy of their absolute ages seems valid4-6. We report here the results of radiometric dates of the Yuha burial site from Imperial County, California, for which the geology and stratigraphy have been documented and reported in detail7. ?? 1976 Nature Publishing Group.

  3. A Comprehensive Database for the Most Commonly Measured Paleoceanographic Proxies: Evaluating Global Carbon Burial Variations over the Last Deglaciation

    NASA Astrophysics Data System (ADS)

    Cartapanis, O. A.; Galbraith, E. D.; Bianchi, D.

    2014-12-01

    The paleoceanographic community has measured physical and chemical properties of thousands of sediment cores, in order to reconstruct past oceanic conditions across a wide range of timescales. Most of these datasets were archived in online data repositories in order to facilitate later analysis. However, the diversity of proxy types and heterogeneous reporting standards have hindered the analysis of globally distributed paleoceanographic time series, despite the tremendous potential utility of large datasets. In order for the existing archives of paleoceanographic data to contribute towards important unanswered issues, the datasets must be readily accessible in an organized structure, with an appropriate unified age model for each sediment site. Here we present a comprehensive database, built using MATLAB structure, for the most commonly measured proxies in marine sediment cores and surface sediment. These include the concentrations of carbonate, organic matter and opal, density of the sediment, the oxygen and carbon isotopic composition of benthic and planktonic foraminifera, sea surface temperature estimates, as well as chronological constrains. The records were downloaded from PANGAEA and NOAA databases and multiple records from the same sediment core were regrouped, allowing age models to be shared between records. The resulting database consists of more than 30,000 sites, facilitating rapid and accurate mapping of sediment composition for selected time periods, and retrieving and plotting time series. The greatest hurdle identified in building a unifi­ed dataproduct of this type is inconsistency in the reporting of depth measurements and chronological information. In our view, standardized reporting practices would greatly assist in developing global quantitative analysis, and requires community-wide action. We propose the development of a unified global sediment core registry, including metadata and chronological information for all marine sediment cores

  4. In situ spectroscopic detection of SMSI effect in a Ni/CeO2 system: hydrogen-induced burial and dig out of metallic nickel

    SciTech Connect

    Caballero, Alfonso; Holgado, Juan P.; Gonzalez-delaCruz, Victor M.; Habas, Susan e.; Herranz, Tirma; Salmeron, Miquel

    2010-06-29

    In situ APPES technique demonstrates that the strong metal support interaction effect (SMSI) in the Ni-ceria system is associated with the decoration and burial of metallic particles by the partially reduced support, a phenomenon reversible by evacuation at high temperature of the previously absorbed hydrogen.

  5. A re-evaluation of geological timescale benchmarks and temperature sensitivity of fission-track annealing in apatites

    NASA Astrophysics Data System (ADS)

    Luijendijk, Elco; Andriessen, Paul

    2016-04-01

    Current models of the temperature sensitivity of fission track annealing in apatites have been calibrated using fission track data from boreholes, with the assumption that these samples are currently at maximum burial depth and temperatures. The most detailed data-set comes from boreholes located in the Otway basin, Australia. However, several lines of evidence suggest that these samples are not at their maximum burial depth and temperature and consequently the cooling temperature of the apatite fission track thermochronometer would then be higher than previously assumed. Significant late Cenozoic exhumation in the Otway Basin was suggested by earlier studies that document a major late-Miocene erosional unconformity, folding and trusting of underlying sediments and elevated strandlines along the coast. In addition, anomalously young apatite (U-Th)/He ages in several boreholes in the basin suggest that the basin's sediments have been exhumed and cooled in the late Cenozoic. We explore the effects of late Cenozoic exhumation on fission track data in the Otway basin using a 1D model of burial and thermal history. We show that simulating several 100s of meters of exhumation in the basin results in significant misfit between current annealing models and observed fission track data. The additional exhumation reconciles the Otway basin data with a second detailed fission track dataset from boreholes in Southern Texas with a well-constrained thermal and burial history. We combine vitrinite reflectance data and U-Th/He data from the Otway basin to recalibrate the burial history of the Otway basin. Subsequently we combine the new thermal history of the Otway basin with the Southern Texas dataset to recalibrate the fission track annealing algorithm. The results suggest that fission-track annealing in apatites is underestimated by approximately 20°C by current annealing models, with significant implications for studies that use apatite fission track thermochronology to

  6. Single-grain optical dating of grave-infill associated with human burials at Lake Mungo, Australia

    NASA Astrophysics Data System (ADS)

    Olley, Jon M.; Roberts, Richard G.; Yoshida, Hiroyuki; Bowler, James M.

    2006-10-01

    Recent age constraints on Australia's oldest human remains (Mungo I and III), found at Lake Mungo in western New South Wales, relied on optical dating of sands from the same stratigraphic units as those into which the remains had been inserted (42±3 ka) and those that overlay the graves (38±2 ka), giving a burial age of 40±2 ka. This indirect means of dating the burials was necessary because the original site from which the remains had been excavated had been completely eroded away. At the time of the original excavation of the Mungo III grave, blocks of sediment from the grave-infill were collected for sediment fabric analysis. These sediment blocks were impregnated with polyester resin, sectioned for analysis and the remaining resin-impregnated sediment blocks were then stored in a cupboard, where they have lain for the last 30 years. Here we report on optical dating of single grains of quartz extracted from one of these sediment blocks. Grains extracted from the centre of the block show a wide distribution of equivalent doses (0.0±0.3 to 43.7±8.3 Gy), indicating that not all of the grains have remained hidden from light (light-safe) following excavation. We show that the population of grains with the maximum equivalent dose produces an age consistent with that of the previous study, indicating that some of the grains have remained light-safe. We also use linearly modulated optically stimulated luminescence to identify light-safe grains. These yield an age of 41±4 ka, which represents a direct optical age for the grave-infill and which is consistent with the age obtained in the previous study for sands from the same stratigraphic unit as that containing the burial. The results reported here demonstrate the potential of applying optical dating to archived sediment samples that have not been stored in a light-safe environment.

  7. Littoral assessment of mine burial signatures (LAMBS): buried-landmine hyperspectral data collections

    NASA Astrophysics Data System (ADS)

    Kenton, Arthur C.; Geci, Duane M.; McDonald, James A.; Ray, Kristofer J.; Thomas, Clayton M.; Holloway, John H., Jr.; Petee, Danny A.; Witherspoon, Ned H.

    2003-09-01

    The objective of the Office of Naval Research (ONR) Rapid Overt Reconnaissance (ROR) program and the Airborne Littoral Reconnaissance Technologies project's Littoral Assessment of Mine Burial Signatures (LAMBS) contract is to determine if electro-optical spectral discriminants exist that are useful for the detection of land mines located in littoral regions. Statistically significant buried mine overburden and background signature data were collected over a wide spectral range (0.35 to 14 μm) to identify robust spectral features that might serve as discriminants for new airborne sensor concepts. The LAMBS program further expands the hyperspectral database previously collected and analyzed on the U.S. Army's Hyperspectral Mine Detection Phenomenology program [see "Detection of Land Mines with Hyperspectral Data," and "Hyperspectral Mine Detection Phenomenology Program," Proc. SPIE Vol. 3710, pp 917-928 and 819-829, AeroSense April 1999] to littoral areas where tidal, surf, and wind action can additionally modify spectral signatures. This work summarizes the LAMBS buried mine collections conducted at three beach sites - an inland bay beach site (Eglin AFB, FL, Site A-22), an Atlantic beach site (Duck, NC), and a Gulf beach site (Eglin AFB, FL, Site A-15). Characteristics of the spectral signatures of the various dry and damp beach sands are presented. These are then compared to buried land mine signatures observed for the tested background types, burial ages, and environmental conditions experienced.

  8. Re-evaluating luminescence burial doses and bleaching of fluvial deposits using Bayesian computational statistics

    NASA Astrophysics Data System (ADS)

    Cunningham, A. C.; Wallinga, J.; Hobo, N.; Versendaal, A. J.; Makaske, B.; Middelkoop, H.

    2015-01-01

    The optically stimulated luminescence (OSL) signal from fluvial sediment often contains a remnant from the previous deposition cycle, leading to a partially bleached equivalent-dose distribution. Although identification of the burial dose is of primary concern, the degree of bleaching could potentially provide insights into sediment transport processes. However, comparison of bleaching between samples is complicated by sample-to-sample variation in aliquot size and luminescence sensitivity. Here we begin development of an age model to account for these effects. With measurement data from multi-grain aliquots, we use Bayesian computational statistics to estimate the burial dose and bleaching parameters of the single-grain dose distribution. We apply the model to 46 samples taken from fluvial sediment of Rhine branches in the Netherlands, and compare the results with environmental predictor variables (depositional environment, texture, sample depth, depth relative to mean water level, dose rate). Although obvious correlations with predictor variables are absent, there is some suggestion that the best-bleached samples are found close to the modern mean water level, and that the extent of bleaching has changed over the recent past. We hypothesise that sediment deposited near the transition of channel to overbank deposits receives the most sunlight exposure, due to local reworking after deposition. However, nearly all samples are inferred to have at least some well-bleached grains, suggesting that bleaching also occurs during fluvial transport.

  9. Direct burial and vault emplacement data quality comparison at Dotson Ranch, New Mexico

    NASA Astrophysics Data System (ADS)

    Beaudoin, B. C.; Aderhold, K.; Anderson, K.; Pfeifer, M.; Parker, T.; Miller, P. E.; Slad, G. W.; Reusch, A.

    2013-12-01

    noise levels are similar at all sensors and are likely due to cultural activity and temperature fluctuations. The conclusion from this study is that the shallow vault emplacement method does not provide significant improvement in data quality compared to direct burial emplacement method. Further experiments are underway in a less noisy environment at Poker Flat Research Range in Alaska.

  10. Low-temperature atmospheric plasma increases the expression of anti-aging genes of skin cells without causing cellular damages.

    PubMed

    Choi, Jeong-Hae; Lee, Hyun-Wook; Lee, Jae-Koo; Hong, Jin-woo; Kim, Gyoo-cheon

    2013-03-01

    Efforts to employ various types of plasma in the field of skin care have increased consistently because it can regulate many biochemical reactions that are normally unaffected by light-based therapy. One method for skin rejuvenation adopted a high-temperature plasma generator to remove skin epithelial cells. In this case, the catalyzing effects of the plasma were rarely used due to the high temperature. Hence, the benefits of the plasma were not magnified. Recently, many types of low-temperature plasma devices have been developed for medical applications but their detailed functions and working mechanisms are unclear. The present study examined the effect of low-temperature microwave plasma on skin cells. Treatment with low-temperature plasma increased the expression of anti-aging genes in skin cells, including collagen, fibronectin and vascular endothelial growth factor. Furthermore, the plasma treatment did not cause cell death, but only induced slight cell growth arrest at the G2 phase. Although the cells treated with low-temperature plasma showed moderate growth arrest, there were no signs of thermal or genetic damage of skin cells. Overall, this low-temperature microwave plasma device induces the expressions of some anti-aging-related genes in skin cells without causing damage. PMID:22773133

  11. Evolution of magnetic phase at low aging temperature in a heavily cold-drawn stainless steel fiber

    NASA Astrophysics Data System (ADS)

    Yang, Shun-Tung; Hwang, Weng-Sing; Shyr, Tien-Wei; Cheng, I.-Lin

    2012-08-01

    The evolution of the magnetic phase upon aging at 300-520 °C in a heavily cold-drawn AISI 316L austenitic stainless steel fiber was studied using thermomagnetic analysis (TMA) and magnetic force microscopy with a heating stage. An increasing trend of magnetization from 50 °C to around 470 °C in the heating curves of TMA in austenitic stainless steels after a cold-drawing process was observed. No significant Ms temperature signal in the TMA curve at cooling indicated an increase in magnetization upon cooling period without significant phase transformation. A series of in situ magnetic force microscopy observations reveal a growth of the magnetic domain structure after aging at 300 °C for 2.5 h. Results show that the ferromagnetic increase during aging at lower annealing temperature resulted from the growth of martensite.

  12. (U-Th)/He Ages from Martian Meteorites Zagami and ALHA77005: Their Implications to Shock Temperatures

    NASA Astrophysics Data System (ADS)

    Min, K. K.; Farah, A.

    2011-12-01

    Thermal histories of Martian meteorites provide important clues regarding the surface conditions of Mars, ejection dynamics of meteorites from Mars, and their delivery process to Earth. To investigate the peak shock temperatures of Zagami and ALHA77005 Martian meteorites during their ejection from Mars, we applied (U-Th)/He thermochronometry to multiple phosphate aggregates. A total of 248 phosphate aggregates (merrillite crystals with other attached phases) were identified using Scanning Electron Microscopy (SEM), and then grouped together in samples of five to twenty aggregates in order to measure U, Th, Sm and He abundances. The resulting (U-Th)/He ages are widely distributed in the range of 19.8 Ma - 202.4 Ma for Zagami. The ages from large aggregates (150-250 μm: 147 ± 35 Ma) are generally older than the ages from the smaller groups (75-250 μm, 51 ± 31 Ma). The textural relationships of the phosphates with neighboring phases in the aggregates were investigated using SEM and BSE (Back-Scattered Electron) imaging to understand the age distribution. Among the most contrasting features is that the larger aggregates contain thicker (>20 μm) layers of attached phases, whereas the smaller aggregates exhibit much thinner (<20 μm) corresponding layers. These observations imply that the large aggregates, with thick exotic layers, experienced least alpha-recoil loss, thus generating reliable (U-Th)/He ages. In contrast, the smaller aggregates' external layers lack sufficient thickness to shield recoiled alphas, and subsequently yielding apparently younger (U-Th)/He ages. For ALHA77005, the (U-Th)/He ages are relatively well constrained in the range of 5.9 Ma - 17.9 Ma (11.4 ± 5.8 Ma) with one outlier of 78.2 Ma. The limited amount of sample for ALHA77005 preempted us from testing any size effects on the ages. The peak shock temperatures of these two meteorites were estimated using a simple volume diffusion model with an assumption that all He loss occurred during

  13. Evaluation of local structure alphabets based on residue burial.

    PubMed

    Karchin, Rachel; Cline, Melissa; Karplus, Kevin

    2004-05-15

    Residue burial, which describes a protein residue's exposure to solvent and neighboring atoms, is key to protein structure prediction, modeling, and analysis. We assessed 21 alphabets representing residue burial, according to their predictability from amino acid sequence, conservation in structural alignments, and utility in one fold-recognition scenario. This follows upon our previous work in assessing nine representations of backbone geometry.1 The alphabet found to be most effective overall has seven states and is based on a count of C(beta) atoms within a 14 A-radius sphere centered at the C(beta) of a residue of interest. When incorporated into a hidden Markov model (HMM), this alphabet gave us a 38% performance boost in fold recognition and 23% in alignment quality. PMID:15103615

  14. The effects of physical aging at elevated temperatures on the viscoelastic creep on IM7/K3B

    NASA Technical Reports Server (NTRS)

    Gates, Thomas S.; Feldman, Mark

    1994-01-01

    Physical aging at elevated temperature of the advanced composite IM7/K3B was investigated through the use of creep compliance tests. Testing consisted of short term isothermal, creep/recovery with the creep segments performed at constant load. The matrix dominated transverse tensile and in-plane shear behavior were measured at temperatures ranging from 200 to 230 C. Through the use of time based shifting procedures, the aging shift factors, shift rates and momentary master curve parameters were found at each temperature. These material parameters were used as input to a predictive methodology, which was based upon effective time theory and linear viscoelasticity combined with classical lamination theory. Long term creep compliance test data was compared to predictions to verify the method. The model was then used to predict the long term creep behavior for several general laminates.

  15. Tympanic Membrane Temperature and Emotional Dispositions in Preschool-Aged Children: A Methodological Study

    ERIC Educational Resources Information Center

    Gunnar, Megan R.; Donzella, Bonny

    2004-01-01

    Tympanic membrane (TM) temperature asymmetry has been proposed as a phenotypic marker of vulnerability to negative emotionality in children. Little is known about the stability of TM temperatures or how readily one can obtain a reliable index of the phenotype. TM temperatures were collected from 3- to 5-year-old children (N=73) over 5 months…

  16. Solid Waste Burial Grounds/Central Waste Complex hazards assessment

    SciTech Connect

    Broz, R.E.

    1994-09-30

    This document establishes the technical basis in support of Emergency Planning Activities for Solid Waste Burial Grounds/Central Waste Complex on the Hanford Site. The document represents an acceptable interpretation of the implementing guidance document for DOE Order 5500.3A. Through this document, the technical basis for the development of facility specific Emergency Action Levels and the Emergency Planning Zone is documented.

  17. Enhanced Site Characterization of the 618-4 Burial Ground

    SciTech Connect

    Murray, Christopher J.; Last, George V.; Chien, Yi-Ju

    2001-09-25

    This report describes the results obtained from deployment of the Enhanced Site Characterization System (ESCS) at the Hanford Site's 618-4 Burial Ground. The objective of this deployment was to use advanced geostatistical methods to integrate and interpret geophysical and ground truth data, to map the physical types of waste materials present in unexcavated portions of the burial ground. One issue of particularly interest was the number of drums (containing depleted uranium metal shavings or uranium-oxide powder) remaining in the burial ground and still requiring removal.Fuzzy adaptive resonance theory (ART), a neural network classification method, was used to cluster the study area into 3 classes based on their geophysical signatures. Multivariate statistical analyses and discriminant function analysis (DFA) indicated that the drum area as well as a second area (the SW anomaly) had similar geophysical signatures that were different from the rest of the burial ground. Further analysis of the drum area suggested that as many as 770 drums to 850 drums may remain in that area. Similarities between the geophysical signatures of the drum area and the SW anomaly suggested that excavation of the SW anomaly area also proceed with caution.Deployment of the ESCS technology was successful in integrating multiple geophysical variables and grouping these observations into clusters that are relevant for planning further excavation of the buried ground. However, the success of the technology could not be fully evaluated because reliable ground truth data were not available to enable calibration of the different geophysical signatures against actual waste types.

  18. Constraining multi-stage exposure-burial scenarios for boulders preserved beneath cold-based glacial ice in Thule, northwest Greenland

    NASA Astrophysics Data System (ADS)

    Corbett, Lee B.; Bierman, Paul R.; Rood, Dylan H.

    2016-04-01

    Boulders and landscapes preserved beneath cold-based, non-erosive glacial ice violate assumptions associated with simple cosmogenic exposure dating. In such a setting, simple single isotope exposure ages over-estimate the latest period of surface exposure; hence, alternate approaches are required to constrain the multi-stage exposure/burial histories of such samples. Here, we report 28 paired analyses of 10Be and 26Al in boulder samples from Thule, northwest Greenland. We use numerical models of exposure and burial as well as Monte Carlo simulations to constrain glacial chronology and infer process in this Arctic region dominated by cold-based ice. We investigate three specific cases that can arise with paired nuclide data: (1) exposure ages that are coeval with deglaciation and 26Al/10Be ratios consistent with constant exposure; (2) exposure ages that pre-date deglaciation and 26Al/10Be ratios consistent with burial following initial exposure; and (3) exposure ages that pre-date deglaciation and 26Al/10Be ratios consistent with constant exposure. Most glacially-transported boulders in Thule have complex histories; some were exposed for tens of thousands of years and buried for at least hundreds of thousands of years, while others underwent only limited burial. These boulders were probably recycled through different generations of till over multiple glacial/interglacial cycles, likely experiencing partial or complete shielding during interglacial periods due to rotation or shallow burial by sediments. Our work demonstrates that the landscape in Thule, like many high-latitude landscapes, was shaped over long time durations and multiple glacial and interglacial periods throughout the Quaternary.

  19. Burial diagenesis and geochemical alterations and their relationship to high fluid pressures, Frio and Vicksburg shales

    SciTech Connect

    Bott, W.F. Jr.; Tieh, T.T.

    1987-09-01

    Depth-related mineralogic changes in Frio and Vicksburg shales from Ann-Mag field, Brooks County, Texas, were studied to assess the nature and extent of burial diagenesis and geochemical alterations, and to determine their relationship to development of high fluid pressures. Mixed-layer illite-smectite and illite dominate the mineralogy of the shales. Burial diagenesis has transformed randomly interstratified illite/smectite to regularly interstratified illite/smectite and to illite, over a depth range of 6000-10,400 ft (1828-3170 m). The quantity of expandable smectite layers in the fine clay fraction decreases from 70% in the shallowest sample to 22% in the deepest sample, whereas illite increases from 27 to 61%. Alteration of feldspar in the fine silt fraction probably provided the potassium required in this reaction. An abrupt increase of smectite to illite alteration occurs at a depth of approximately 8900 ft (2713 m), corresponding to a temperature of 224/sup 0/F (107/sup 0/C). Fluid pressures estimated from conductivity data and measured pressures show that, at this depth, a significant increase in fluid pressure takes place. Associated with this increase is a decrease in shale density. These relationships suggest that high fluid pressures in this field are caused by clay transformation reactions that expel interlayer water into the pore spaces. Upward movement of pore fluids in thick shales is also suggested by extractable cation determinations.

  20. Leaf-age effects on temperature responses of photosynthesis and respiration of an alpine oak, Quercus aquifolioides, in southwestern China.

    PubMed

    Zhou, Haoran; Xu, Ming; Pan, Hongli; Yu, Xiubo

    2015-11-01

    Temperature responses and sensitivity of photosynthesis (A(n_)T) and respiration for leaves at different ages are crucial to modeling ecosystem carbon (C) cycles and productivity of evergreen forests. Understanding the mechanisms and processes of temperature sensitivity may further shed lights on temperature acclimation of photosynthesis and respiration with leaf aging. The current study examined temperature responses of photosynthesis and respiration of young leaves (YLs) (fully expanded in current growth season) and old leaves (OLs) (fully expanded in last growth season) of Quercus aquifolioides Rehder and E.H. Wilson in an alpine oak forest, southwestern China. Temperature responses of dark respiration (R(dark)), net assimilation (A(n)), maximal velocity of carboxylation (V(cmax)) and maximum rate of electron transport (J(max)) were significantly different between the two leaf ages. Those differences implied different temperature response parameters should be used for leaves of different ages in modeling vegetation productivity and ecosystem C cycles in Q. aquifolioides forests and other evergreen forests. We found that RuBP carboxylation determined the downward shift of A(n_)T in OLs, while RuBP regeneration and the balance between Rubisco carboxylation and RuBP regeneration made little contribution. Sensitivity of stomatal conductance to vapor pressure deficit changed in OLs and compensated part of the downward shift. We also found that OLs of Q. aquifolioides had lower An due to lower stomatal conductance, higher stomatal conductance limitation and deactivation of the biochemical processes. In addition, the balance between R(dark) and A(n) changed between OLs and YLs, which was represented by a higher R(dark)/A(n) ratio for OLs. PMID:26452765

  1. A rift-related origin for regional medium-pressure, high-temperature metamorphism

    NASA Astrophysics Data System (ADS)

    Tucker, Naomi M.; Hand, Martin; Payne, Justin L.

    2015-07-01

    Crustal-scale exhumation during the Alice Springs Orogeny (c. 450-320 Ma) in central Australia has exposed a region of medium-pressure, high-temperature metasedimentary and metabasic rocks that comprise the Harts Range Group (HRG). Similarities in the detrital zircon age spectra between the HRG and surrounding unmetamorphosed, intraplate late Neoproterozoic-Cambrian basin sequences suggest that the HRG is a highly metamorphosed equivalent of these successions. Calculated phase equilibria modelling and thermobarometry constrain peak metamorphic conditions to ˜ 880 °C and 10.5 kbar, and ˜ 680 °C and 5.5-8.0 kbar, in the structurally lowest and highest parts of the HRG, respectively. Metamorphic conditions also indicate that burial occurred along a near-linear moderately-high apparent thermal gradient, recorded by the prograde development of andalusite-bearing mineral assemblages at shallower structural levels. Prograde and peak metamorphism was associated with voluminous intrusive and extrusive mafic magmatism, the development of a coarse layer-parallel fabric and north-directed normal shear-sense kinematics. Collectively, these point to an extensional regime. Furthermore, burial and metamorphism at c. 480-460 Ma was concurrent with a shallow epicontinental marine environment and ongoing sedimentation in central Australia. Accordingly, the deep burial, metamorphism and deformation of the HRG to mid-lower crustal depths (˜ 20- 35 km) must be justified in the context of the broader intraplate basin evolution at this time. It is difficult to reconcile medium-pressure, high-temperature metamorphism of the HRG with deep burial by tectonic overthickening which is commonly assumed to be the case. In contrast, metamorphism of the HRG seems more compatible with burial within a deep rift-style basin driven by high heat flow and mafic magmatism, suggesting that regional medium-pressure metamorphic terranes are not necessarily reflective of compressional thickening of the

  2. Undulation frequency affects burial performance in living and model flatfishes.

    PubMed

    McKee, Amberle; MacDonald, Ian; Farina, Stacy C; Summers, Adam P

    2016-04-01

    Flatfishes bury themselves under a thin layer of sand to hide from predators or to ambush prey. We investigated the role of undulation frequency of the body in burial in five species of flatfishes (Isopsetta isolepis, Lepidopsetta bilineata, Hippoglossoides elassodon, Parophrys vetulus, and Psettichthys melanostictus). High-speed videos show that undulations begin cranially and pass caudally while burying, as in forward swimming in many other fishes. The flatfishes also flick the posterior edge of their dorsal and anal fins during burial, which may increase the total surface area covered by substrate. We built a simple physical model - a flexible, oval silicone plate with a motorized, variable-speed actuator - to isolate the effect of undulation frequency on burial. In both the model and actuated dead flatfish, increased undulation frequency resulted in an increase in the area of sand coverage. Complete coverage required an undulation frequency of no more than 10Hz for our models, and that was also sufficient for live flatfishes. The model shows that undulation is sufficient to bury the animal, but live flatfishes showed a superior ability to bury, which we attribute to the action of the median fins. PMID:26763759

  3. Self-burial mechanics of hygroscopically responsive awns.

    PubMed

    Jung, Wonjong; Kim, Wonjung; Kim, Ho-Young

    2014-12-01

    We present the results of a combined experimental and theoretical investigation of the mechanics of self-burial of some plant seeds whose morphologies respond to environmental changes in humidity. The seeds of Erodium and Pelargonium have hygroscopically responsive awns that play a critical role in their self-burial into soil. The awn, coiled in a dry state, uncoils to stretch linearly under highly humid condition because of a tilted arrangement of cellulose microfibrils in one of the layers of the awn's bilayered structure. By measuring the mechanical characteristics of the awns of Pelargonium carnosum, we find that the extensional force of the awn can be aptly modeled by the theory of elasticity for a coiled spring. We further show that although the resistance to the seed-head penetrating relatively coarse soils without spinning is large enough to block the digging seed, the rotation of the seed greatly reduces the soil's resistance down to a level the awn can easily overcome. Our mechanical analysis reveals that the self-burial of the seed is a sophisticated outcome of the helically coiled configuration of the awn. PMID:24760793

  4. Self-burial mechanics of hygroscopically active awns

    NASA Astrophysics Data System (ADS)

    Jung, Wonjong; Kim, Wonjung; Kim, Ho-Young

    2013-11-01

    We present the results of a combined experimental and theoretical investigation of the mechanics of self-burial of some plant seeds whose morphologies respond to humidity change of the surroundings. The seeds of Pelargonium species have hygroscopically active awns that play a critical role in the dispersal from the parent plant and burial in soil. While the awn uncoils to a linear shape in a highly humid condition, it recoils to a helical shape when dry. The rotation is driven by the structure of the cell walls that are comprised of cellulose microfibers aligned in a tilted helix. During uncoiling of the awn, the revolving tail generates thrust to burrow into soil, so that the seed is self-buried. We present the direct observation of the self-burial of the seed with the thrust into a soft substrate being measured at the same time. The elastica theory allows us to rationalize this botanical digging mechanics using the structural deformations of the hygroexpansive tissues. This work was supported by the Sogang University Research Grant of 2013 (201310009.01) and the National Research Foundation of Korea (grant no. 2012-008023).

  5. Ground resistance influences lizard burial in dry and wet sand

    NASA Astrophysics Data System (ADS)

    Sharpe, Sarah; Kuckuk, Robyn; Goldman, Daniel

    2012-11-01

    Many terrestrial animals move within soil in which water content can vary, and little is known about how water content affects locomotor performance. To investigate the effect of water content on burial, we created controlled dry and wet substrates. We used 0.3 mm glass particles and varied water content W, the mass of water to mass of dry loosely packed sand. Drag force on a submerged 1.6 cm diameter rod increased by a factor of 4 as W increased from 0 to 0.03, after which force increases were small. Drag force in wet media periodically fluctuated with time and corresponded with surface fracturing. We characterized how W affected burial performance and strategy of a generalist burrower, the ocellated skink lizard (Chalcides ocellatus). High speed x-ray imaging was used to measure head, body and limb kinematics in substrates with W= 0 and W= 0.03. In both states during burial the body was maintained in a curved posture and the animal moved using a start-stop motion. During movement, the head oscillated and the forelimb on the convex side of the body was used to push the animal forward. Both speed and angular excursion of the head oscillation decreased in the W= 0.03 state. The differences in locomotion were attributed to the changing resistance force within the media.

  6. Interaction of cyclic ageing at high-rate and low temperatures and safety in lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Fleischhammer, Meike; Waldmann, Thomas; Bisle, Gunther; Hogg, Björn-Ingo; Wohlfahrt-Mehrens, Margret

    2015-01-01

    The differences in the safety behaviour between un-aged and aged high-power 18650 lithium-ion cells were investigated at the cell and material level by Accelerating Rate Calorimetry (ARC) and Simultaneous Thermal Analysis (STA). Commercial cells containing a LixNi1/3Mn1/3Co1/3O2/LiyMn2O4 blend cathode, a carbon/graphite anode and a PP/PE/PP trilayer separator were aged by high-rate and low temperature cycling, leading to (i) mechanical deformation of the jelly roll and (ii) lithium plating on the anode. The results show a strong influence of the ageing history on the safety behaviour. While cycling at high current does not have a strong influence on the cell safety, lithium plating leads to a significant increase of heat formation during thermal runaway and thus to a higher hazard of safety.

  7. NEUROTOXICITY OF CARBARYL IN THE AGING BROWN NORWAY RAT: EFFECTS ON CORE TEMPERATURE AND MOTOR ACTIVITY.

    EPA Science Inventory

    The US EPA is pursuing a variety of research efforts to assess the susceptibility of the aged to neurotoxicants. The BN strain is a popular animal model for aging studies but there is a need for improved methods of monitoring their physiological responses to neurotoxicants over t...

  8. Low-Temperature Aging Characteristics of Type 316L Stainless Steel Welds: Dependence on Solidification Mode

    NASA Astrophysics Data System (ADS)

    Abe, Hiroshi; Watanabe, Yutaka

    2008-06-01

    Thermal aging embrittlement of light water reactor (LWR) components made of stainless steel cast has been recognized as a potential degradation issue, and careful attention has been paid to it. Although welds of austenitic stainless steels have γ-δ duplex microstructure, which is similar to that of the stainless steel cast, examination of the thermal aging characteristics of the stainless steel welds is very limited. In this investigation, two types of type 316L stainless steel weld metal with different solidification modes were prepared using two kinds of filler metals having tailored Ni equivalent and Cr equivalent. Differences between the two weld metals in the morphology of microstructure, in the composition of δ-ferrite, and in hardening behaviors with isothermal aging at 335 °C have been investigated. The hardness of the ferrite phase has increased with aging time, while the hardness of austenite phase has stayed the same. The mottled aspect has been observed in δ-ferrite of aged samples by transmission electron microscopy (TEM) observation. These characteristics suggest that spinodal decomposition has occurred in δ-ferrite by aging at 335 °C. The age-hardening rate of δ-ferrite was faster for the primary austenite solidification mode (AF mode) sample than the primary ferrite solidification mode (FA mode) sample in the initial stage of the aging up to 2000 hours. It has been suggested that the solidification mode can affect the kinetics of spinodal decomposition.

  9. Early-type galaxy archeology: Ages, abundance ratios, and effective temperatures from full-spectrum fitting

    SciTech Connect

    Conroy, Charlie; Graves, Genevieve J.; Van Dokkum, Pieter G.

    2014-01-01

    The stellar populations of galaxies hold vital clues to their formation histories. In this paper we present results based on modeling stacked spectra of early-type galaxies drawn from the Sloan Digital Sky Survey as a function of velocity dispersion, σ, from 90 km s{sup –1} to 300 km s{sup –1}. The spectra are of extremely high quality, with typical signal-to-noise ratio of 1000 Å{sup –1}, and a wavelength coverage of 4000 Å –8800 Å. Our population synthesis model includes variation in 16 elements from C to Ba, a two-component star formation history, the shift in effective temperature, Δ T {sub eff}, of the stars with respect to a solar metallicity isochrone, and the stellar initial mass function, among other parameters. In our approach we fit the full optical spectra rather than a select number of spectral indices and are able to, for the first time, measure the abundances of the elements V, Cr, Mn, Co, and Ni from the integrated light of distant galaxies. Our main results are as follows: (1) light-weighted stellar ages range from 6-12 Gyr from low to high σ; (2) [Fe/H] varies by less than 0.1 dex across the entire sample; (3) Mg closely tracks O, and both increase from ≈0.0 at low σ to ∼0.25 at high σ; Si and Ti show a shallower rise with σ, and Ca tracks Fe rather than O; (4) the iron peak elements V, Cr, Mn, and Ni track Fe, while Co tracks O, suggesting that Co forms primarily in massive stars; (5) C and N track O over the full sample and [C/Fe] and [N/Fe] exceed 0.2 at high σ; and (6) the variation in Δ T {sub eff} with total metallicity closely follows theoretical predictions based on stellar evolution theory. This last result is significant because it implies that we are robustly solving not only for the detailed abundance patterns but also the detailed temperature distributions (i.e., isochrones) of the stars in these galaxies. A variety of tests reveal that the systematic uncertainties in our measurements are probably 0.05 dex or

  10. Early-type Galaxy Archeology: Ages, Abundance Ratios, and Effective Temperatures from Full-spectrum Fitting

    NASA Astrophysics Data System (ADS)

    Conroy, Charlie; Graves, Genevieve J.; van Dokkum, Pieter G.

    2014-01-01

    The stellar populations of galaxies hold vital clues to their formation histories. In this paper we present results based on modeling stacked spectra of early-type galaxies drawn from the Sloan Digital Sky Survey as a function of velocity dispersion, σ, from 90 km s-1 to 300 km s-1. The spectra are of extremely high quality, with typical signal-to-noise ratio of 1000 Å-1, and a wavelength coverage of 4000 Å -8800 Å. Our population synthesis model includes variation in 16 elements from C to Ba, a two-component star formation history, the shift in effective temperature, Δ T eff, of the stars with respect to a solar metallicity isochrone, and the stellar initial mass function, among other parameters. In our approach we fit the full optical spectra rather than a select number of spectral indices and are able to, for the first time, measure the abundances of the elements V, Cr, Mn, Co, and Ni from the integrated light of distant galaxies. Our main results are as follows: (1) light-weighted stellar ages range from 6-12 Gyr from low to high σ (2) [Fe/H] varies by less than 0.1 dex across the entire sample; (3) Mg closely tracks O, and both increase from ≈0.0 at low σ to ~0.25 at high σ Si and Ti show a shallower rise with σ, and Ca tracks Fe rather than O; (4) the iron peak elements V, Cr, Mn, and Ni track Fe, while Co tracks O, suggesting that Co forms primarily in massive stars; (5) C and N track O over the full sample and [C/Fe] and [N/Fe] exceed 0.2 at high σ and (6) the variation in Δ T eff with total metallicity closely follows theoretical predictions based on stellar evolution theory. This last result is significant because it implies that we are robustly solving not only for the detailed abundance patterns but also the detailed temperature distributions (i.e., isochrones) of the stars in these galaxies. A variety of tests reveal that the systematic uncertainties in our measurements are probably 0.05 dex or less. Our derived [Mg/Fe] and [O

  11. Multibeam observations of mine burial near Clearwater, FL, including comparisons to predictions of wave-induced burial

    USGS Publications Warehouse

    Wolfson, M.L.; Naar, D.F.; Howd, P.A.; Locker, S.D.; Donahue, B.T.; Friedrichs, Carl T.; Trembanis, A.C.; Richardson, M.D.; Wever, T.F.

    2007-01-01

    A Kongsberg Simrad EM 3000 multibeam sonar (Kongsberg Simrad, Kongsberg, Norway) was used to conduct a set of six repeat high-resolution bathymetric surveys west of Indian Rocks Beach (IRB), just to the south of Clearwater, FL, between January and March 2003, to observe in situ scour and burial of instrumented inert mines and mine-like cylinders. Three closely located study sites were chosen: two fine-sand sites, a shallow one located in ??? 13 m of water depth and a deep site located in ???14 m of water depth; and a coarse-sand site in ???13 m. Results from these surveys indicate that mines deployed in fine sand are nearly buried within two months of deployment (i.e., they sunk 74.5% or more below the ambient seafloor depth). Mines deployed in coarse sand showed a lesser amount of scour, burying until they present roughly the same hydrodynamic roughness as the surrounding rippled bedforms. These data were also used to test the validity of the Virginia Institute of Marine Science (VIMS, Gloucester Point, VA) 2-D burial model. The model worked well in areas of fine sand, sufficiently predicting burial over the course of the experiment. In the area of coarse sand, the model greatly overpredicted the amount of burial. This is believed to be due to the presence of rippled bedforms around the mines, which affect local bottom morphodynamics and are not accounted for in the model, an issue currently being addressed by the modelers. This paper focuses specifically on two instrumented mines: an acoustic mine located in fine sand and an optical instrumented mine located in coarse sand. ?? 2007 IEEE.

  12. Circadian rhythms of body temperature and locomotor activity in aging BALB/c mice: early and late life span predictors.

    PubMed

    Basso, Andrea; Del Bello, Giovanna; Piacenza, Francesco; Giacconi, Robertina; Costarelli, Laura; Malavolta, Marco

    2016-08-01

    Impairment of one or more parameters of circadian rhythms (CR) of body temperature (BT) and locomotor activity (LMA) are considered among the hallmarks of mammalian aging. These alterations are frequently used as markers for imminent death in laboratory mice. However, there are still contradictory data for particular strains and it is also uncertain which changes might predict senescence changes later in life, including the force of mortality. In the present paper we use telemetry to study LMA and CR of BT during aging of BALB/c mice. At our knowledge this is the first time that CR of BT and LMA are investigated in this strain in a range of age covering the whole lifespan, from young adult up to very old age. CR of BT was analyzed with a cosine model using a cross sectional approach and follow-up measurements. The results show that BT, LMA, amplitude, goodness-of-fit (GoF) to circadian cycle of temperature decrease with different shapes during chronological age. Moreover, we found that the % change of amplitude and BT in early life (5-19 months) can predict the remaining lifespan of the mice. Later in life (22-32 months), best predictors are single measurements of LMA and GoF. The results of this study also offer potential measures to rapidly identifying freely unrestrained mice with the worst longitudinal outcome and against which existing or novel biomarkers and treatments may be assessed. PMID:26820297

  13. Influence of temperature, environment, and thermal aging on the continuous cycle fatigue behavior of Hastelloy X and Inconel 617

    SciTech Connect

    Strizak, J.P.; Brinkman, C.R.; Booker, M.K.; Rittenhouse, P.L.

    1982-04-01

    Results are presented for strain-controlled fatigue and tensile tests for two nickel-base, solution-hardened reference structural alloys for use in several High-Temperature Gas-Cooled Reactor (HTGR) concepts. These alloys, Hastelloy X and Inconel 617, were tested from room temperature to 871/sup 0/C in air and impure helium. Materials were tested in both the solution-annealed and the preaged conditios, in which aging consisted of isothermal exposure at one of several temperatures for periods of up to 20,000 h. Comparisons are given between the strain-controlled fatigue lives of these and several other commonly used alloys, all tested at 538/sup 0/C. An analysis is also presented of the continuous cycle fatigue data obtained from room temperature to 427/sup 0/C for Hastelloy G, Hastelloy X, Hastelloy C-276, and Hastelloy C-4, an effort undertaken in support of ASME code development.

  14. Burial Duration and Frequency Influences Resilience of Differing Propagule Types in a Subtidal Seagrass, Posidonia australis

    PubMed Central

    2016-01-01

    Sedimentation that leads to periodic, and often prolonged, burial events is becoming more common on the world’s coastlines as human populations expand and create urbanised marine environments. Different seagrass species react differently to sediment burial but many species in the southern hemisphere are yet to be examined. How seagrasses react to burial has restoration implications. There is a need to critically assess seagrass transplant propagule responses to periodic (pulse) and prolonged (press) burial events before selecting the most appropriate species, transplant propagule, and transplant site. In my study, mesocosm experiments, coupled with field measurements were used to assess how sexual (seedlings) and vegetative (sprigs) propagules of Posidonia australis responded to pulse and press burial events. Seedlings were highly susceptible to burial (both pulse and press), with no survival at the end of the experimental period. In contrast, rhizome growth in vegetative propagules was stimulated by pulse burial, although press burial events resulted in mortality. The implication for Posidonia australis restoration efforts in areas where burial is periodic, was that vegetative propagules are optimal transplant units, in comparison to seedlings. Press burial however, renders a transplant site sub-optimal for both seedling and sprig transplants. PMID:27526020

  15. Room-temperature aging of Narmco 5208 carbon-epoxy prepreg. II - Physical, mechanical, and nondestructive characterization

    SciTech Connect

    Cole, K.C.; Noel, D.; Hechler, J.-J.; Cielo, P.; Krapez, J.-C. )

    1991-06-01

    Samples of Narmco Rigidite 5208/WC3000 carbon-epoxy composite prepreg were exposed to ambient temperature and 50 percent relative humidity for different periods up to 66 days. The aging has a significant effect on prepreg physical properties such as tack, volatiles content, and gel time. A set of four-ply laminates made from aged prepreg was subjected to tensile testing, ultrasonic inspection, and optothermal inspection. No relationship could be discerned between laminate properties and prepreg aging time. However, variations in panel homogeneity were observed, and these correlated with thermal diffusivity and tensile modulus measurements, but not with ultimate tensile strength or elongation. A set of six-ply laminates was used to measure compressive properties, interlaminar shear strength, and physical properties. These panels also showed variations in porosity, again unrelated to aging, but in addition, the fiber-resin ratio was observed to decrease with aging time. Both factors were found to affect mechanical properties. The implications concerning the importance of monitoring the aging by physicochemical methods are discussed. 30 refs.

  16. Effect of fiber-matrix adhesion on the creep behavior of CF/PPS composites: temperature and physical aging characterization

    NASA Astrophysics Data System (ADS)

    Motta Dias, M. H.; Jansen, K. M. B.; Luinge, J. W.; Bersee, H. E. N.; Benedictus, R.

    2016-06-01

    The influence of fiber-matrix adhesion on the linear viscoelastic creep behavior of `as received' and `surface modified' carbon fibers (AR-CF and SM-CF, respectively) reinforced polyphenylene sulfide (PPS) composite materials was investigated. Short-term tensile creep tests were performed on ±45° specimens under six different isothermal conditions, 40, 50, 60, 65, 70 and 75 °C. Physical aging effects were evaluated on both systems using the short-term test method established by Struik. The results showed that the shapes of the curves were affected neither by physical aging nor by the test temperature, allowing then superposition to be made. A unified model was proposed with a single physical aging and temperature-dependent shift factor, a_{T,te}. It was suggested that the surface treatment carried out in SM-CF/PPS had two major effects on the creep response of CF/PPS composites at a reference temperature of 40 °C: a lowering of the initial compliance of about 25 % and a slowing down of the creep response of about 1.1 decade.

  17. Effect of fiber-matrix adhesion on the creep behavior of CF/PPS composites: temperature and physical aging characterization

    NASA Astrophysics Data System (ADS)

    Motta Dias, M. H.; Jansen, K. M. B.; Luinge, J. W.; Bersee, H. E. N.; Benedictus, R.

    2016-02-01

    The influence of fiber-matrix adhesion on the linear viscoelastic creep behavior of `as received' and `surface modified' carbon fibers (AR-CF and SM-CF, respectively) reinforced polyphenylene sulfide (PPS) composite materials was investigated. Short-term tensile creep tests were performed on ±45° specimens under six different isothermal conditions, 40, 50, 60, 65, 70 and 75 °C. Physical aging effects were evaluated on both systems using the short-term test method established by Struik. The results showed that the shapes of the curves were affected neither by physical aging nor by the test temperature, allowing then superposition to be made. A unified model was proposed with a single physical aging and temperature-dependent shift factor, a_{T,te}. It was suggested that the surface treatment carried out in SM-CF/PPS had two major effects on the creep response of CF/PPS composites at a reference temperature of 40 °C: a lowering of the initial compliance of about 25 % and a slowing down of the creep response of about 1.1 decade.

  18. The Temperature and Cooling Age of the White Dwarf Companion to the Millisecond Pulsar PSR B1855+09.

    PubMed

    van Kerkwijk MH; Bell; Kaspi; Kulkarni

    2000-02-10

    We report on Keck and Hubble Space Telescope observations of the binary millisecond pulsar PSR B1855+09. We detect its white dwarf companion and measure mF555W=25.90+/-0.12 and mF814W=24.19+/-0.11 (Vega system). From the reddening-corrected color, (mF555W-mF814W&parr0;0=1.06+/-0.21, we infer a temperature Teff=4800+/-800 K. The white dwarf mass is known accurately from measurements of the Shapiro delay of the pulsar signal, MC=0.258+0.028-0.016 M middle dot in circle. Hence, given a cooling model, one can use the measured temperature to determine the cooling age. The main uncertainty in the cooling models for such low-mass white dwarfs is the amount of residual nuclear burning, which is set by the thickness of the hydrogen layer surrounding the helium core. From the properties of similar systems, it has been inferred that helium white dwarfs form with thick hydrogen layers, with mass greater, similar3x10-3 M middle dot in circle, which leads to significant additional heating. This is consistent with expectations from simple evolutionary models of the preceding binary evolution. For PSR B1855+09, though, such models lead to a cooling age of approximately 10 Gyr, which is twice the spin-down age of the pulsar. It could be that the spin-down age were incorrect, which would call the standard vacuum dipole braking model into question. For two other pulsar companions, however, ages well over 10 Gyr are inferred, indicating that the problem may lie with the cooling models. There is no age discrepancy for models in which the white dwarfs are formed with thinner hydrogen layers ( less, similar3x10-4 M middle dot in circle). PMID:10642200

  19. Experimental assessment of critical anthropogenic sediment burial in eelgrass Zostera marina.

    PubMed

    Munkes, Britta; Schubert, Philipp R; Karez, Rolf; Reusch, Thorsten B H

    2015-11-15

    Seagrass meadows, one of the world's most important and productive coastal habitats, are threatened by a range of anthropogenic actions. Burial of seagrass plants due to coastal activities is one important anthropogenic pressure leading to the decline of local populations. In our study, we assessed the response of eelgrass Zostera marina to sediment burial from physiological, morphological, and population parameters. In a full factorial field experiment, burial level (5-20cm) and burial duration (4-16weeks) were manipulated. Negative effects were visible even at the lowest burial level (5cm) and shortest duration (4weeks), with increasing effects over time and burial level. Buried seagrasses showed higher shoot mortality, delayed growth and flowering and lower carbohydrate storage. The observed effects will likely have an impact on next year's survival of buried plants. Our results have implications for the management of this important coastal plant. PMID:26388446

  20. Ambient temperature, air pollution, and heart rate variability in an aging population.

    PubMed

    Ren, Cizao; O'Neill, Marie S; Park, Sung Kyun; Sparrow, David; Vokonas, Pantel; Schwartz, Joel

    2011-05-01

    Studies show that ambient temperature and air pollution are associated with cardiovascular disease and that they may interact to affect cardiovascular events. However, few epidemiologic studies have examined mechanisms through which ambient temperature may influence cardiovascular function. The authors examined whether temperature was associated with heart rate variability (HRV) in a Boston, Massachusetts, study population and whether such associations were modified by ambient air pollution concentrations. The population was a cohort of 694 older men examined between 2000 and 2008. The authors fitted a mixed model to examine associations between temperature and air pollution and their interactions with repeated HRV measurements, adjusting for covariates selected a priori on the basis of their previous studies. Results showed that higher ambient temperature was associated with decreases in HRV measures (standard deviation of normal-to-normal intervals, low-frequency power, and high-frequency power) during the warm season but not during the cold season. These warm-season associations were significantly greater when ambient ozone levels were higher (>22.3 ppb) but did not differ according to levels of ambient fine (≤2.5 μm) particulate matter. The authors conclude that temperature and ozone, exposures to both of which are expected to increase with climate change, might act together to worsen cardiovascular health and/or precipitate cardiovascular events via autonomic nervous system dysfunction. PMID:21385834

  1. Temperature and age affect the life history characteristics and fatty acid profiles of Moina macrocopa (Cladocera).

    PubMed

    Gama-Flores, José Luis; Huidobro-Salas, María Elena; Sarma, S S S; Nandini, S; Zepeda-Mejia, Ricardo; Gulati, Ramesh D

    2015-10-01

    Demographic responses and fatty acid profiles of Moina macrocopa were quantified under different temperature regimes (20°C, 25°C and 30°C and diurnally variable 20-30°C) and at fixed ration (10.65µgDWml(-1)) of Chlorella. Highest constant temperature (30°C) reduced the density of M. macrocopa. The cladocerans under the fluctuating temperature regime too had lower population growth (about 50% lower than that at constant 25°C). The survivorship of M. macrocopa was higher at 20°C than that at 25°C and 30°C or at variable temperature regime. Gross and net reproductive rates were higher at 25°C. At 20°C, neonates had the highest proportion (67%) of myristic, palmitic and stearic acids while the adults had the lowest (26%) proportion. For both adults and neonates, palmitoleic, linoleic and linolenic comprised of 15-35% of the total fatty acids. Higher percentage (19%) of linoleic acid was present in adults than neonates (7%). Adults had linolenic acid level which was 3-times higher than in neonates. Linoleic and linolenic fatty acids decreased with increasing temperature for neonates and adults from 20°C to 30°C. The demographic responses and fatty acid profiles of M. macrocopa were discussed in relation to level and mode of temperature exposure. PMID:26590466

  2. Late burial diagenesis of Niagaran (Middle Silurian) pinnacle reefs in Michigan basin

    SciTech Connect

    Cercone, K.R.; Lohmann, K.C. )

    1987-02-01

    Core samples from Middle Silurian pinnacle reefs in northern Michigan exhibit a regionally consistent assemblage of late diagenetic phases including geopetal diagenetic sediment, disseminated pyrite, pyrobitumen, rhombic dolomite cement, and equant calcite spar. High (> 80{degree}C) fluid inclusion homogenization temperatures and inclusions of Silurian-sourced oil in these diagenetic phases indicate that they formed between the Mississippian and Jurassic, when pinnacle reefs resided in the deep subsurface. Fluid inclusion salinities and stable carbon/oxygen isotopic ratios suggest that late diagenetic carbonates did not precipitate from connate fluids but from basinal brines that were conducted to pinnacle reefs by two regional carbonate aquifers. These data confirm that late burial diagenesis can affect carbonate rocks residing in high-salinity, low-permeability fluid environments. 8 figs., 1 tab.

  3. Biomass burial and storage to reduce atmospheric CO2

    NASA Astrophysics Data System (ADS)

    Zeng, N.

    2012-04-01

    To mitigate global climate change, a portfolio of strategies will be needed to keep the atmospheric CO2 concentration below a dangerous level. Here a carbon sequestration strategy is proposed in which certain dead or live trees are harvested via collection or selective cutting, then buried in trenches or stowed away in above-ground shelters. The largely anaerobic condition under a sufficiently thick layer of soil will prevent the decomposition of the buried wood. Because a large flux of CO2 is constantly being assimilated into the world's forests via photosynthesis, cutting off its return pathway to the atmosphere forms an effective carbon sink. It is estimated that a theoretical carbon sequestration potential for wood burial is 10 ± 5 GtC/y, but probably 1-3 GtC/y can be realized in practice. Burying wood has other benefits including minimizing CO2 source from deforestation, extending the lifetime of reforestation carbon sink, and reducing fire danger. There are possible environmental impacts such as nutrient lock-up which nevertheless appears manageable, but other environmental concerns and factors will likely set a limit so that only part of the full potential can be realized. Based on data from forest industry, the cost for wood burial is estimated to be 14/tCO2 (50/tC), lower than the typical cost for power plant CO2 capture with geological storage. The low cost for carbon sequestration with wood burial is possible because the technique uses the natural process of photosynthesis to remove carbon from the atmosphere. The technique is low tech, distributed, safe, and can be stopped at any time, thus an attractive option for large-scale implementation in a world-wide carbon market.

  4. The influence of burial heating on the (U-Th)/He system in apatite: Grand Canyon case study

    NASA Astrophysics Data System (ADS)

    Fox, Matthew; Shuster, David L.

    2014-07-01

    Thermochronological data can constrain the cooling paths of rocks exhumed through the uppermost 1-2 km of earth's crust, and have thus been pivotal in illuminating topographic development over timescales >0.1 Ma. However, in some cases, different methods have led to conflicting conclusions about timing of valley-scale exhumation. Here, we investigate the case of Western Grand Canyon, USA, where different thermochronological datasets have been interpreted to record very different timings of canyon incision (∼70 Ma versus ∼5 Ma). We present a method to assess key assumptions in these constraints and demonstrate that burial heating conditions of basement rocks in the Mesozoic can result in incomplete annealing of radiation damage in apatite. In turn, this has a dramatic effect on the temperature sensitivity of the apatite (U-Th)/He system and its ability to record post-burial exhumation. The possibility of incomplete annealing resolves the apparent conflict in time-temperature paths inferred over the last 70 Ma, although it requires temperatures during burial that are lower than predicted by apatite fission track data. A refinement of parameters that prescribe the kinetics of damage annealing and related control on 4He diffusivity in apatite would account for this discrepancy, specifically if alpha recoil damage anneals at a lower rate than fission tracks at a given temperature. These effects will be important for any application of the apatite (U-Th)/He system in geologic settings that experienced prolonged residence (>10 Ma) between 50-150 °C; the approaches developed here provide means to assess these effects.

  5. Precipitation data for Burial Grounds 5 and 6, Oak Ridge National Laboratory, Tennessee, 1976-1980

    SciTech Connect

    Webster, D A; Beatty, J S; Benjamin, P M; Tranum, W M

    1982-01-01

    As part of a hydrogeologic investigation, precipitation data were collected at two stations, one each in Burial Grounds 5 and 6 at the Oak Ridge National Laboratory, Tennessee. Daily, monthly, and annual values are reported herein for the period from January 1976 through December 1980. During this period, annual values ranged from about 25% above to about 25% below the calculated mean of 51.96 inches at Burial Ground 5 and 49.60 inches at Burial Ground 6.

  6. Geologic setting of the low-level burial grounds

    SciTech Connect

    Lindsey, K.A.; Jaeger, G.K.; Slate, J.L.; Swett, K.J.; Mercer, R.B.

    1994-10-13

    This report describes the regional and site specific geology of the Hanford Sites low-level burial grounds in the 200 East and West Areas. The report incorporates data from boreholes across the entire 200 Areas, integrating the geology of this area into a single framework. Geologic cross-sections, isopach maps, and structure contour maps of all major geological units from the top of the Columbia River Basalt Group to the surface are included. The physical properties and characteristics of the major suprabasalt sedimentary units also are discussed.

  7. Closure Plan for Active Low Level Burial Grounds

    SciTech Connect

    SKELLY, W.A.

    2000-11-16

    This plan has been prepared in response to direction from the U.S. Department of Energy. The purpose of the plan is to define approaches that will be implemented to ensure protection of the public and the environment when active Low-Level Burial Grounds (LLBGs) at the Hanford Site are closed. Performance assessments for active burial grounds in the 200 East and West 200 Areas provide current estimates of potential environmental contamination and doses to the ''maximum exposed individual'' from burial ground operation and closure and compare dose estimates to performance objective dose limits for the facilities. This is an Operational Closure Plan. The intent of the guidance in DOE Order 435.1 is that this plan will be a living document, like the facility performance assessments, and will be revised periodically through the operational life of the LLBGs to reflect updated information on waste inventory. management practices, facility transition planning, schedule dates, assessments of post-closure performance, and environmental consequences. Out year dates identified in this plan are tentative. A Final Closure Plan will be prepared in the future when the timing and extent of closure-related activities for LLBGs can be established with greater certainty. After current operations at the LLBGs are concluded, this plan proposes transitioning of these facilities to the Environmental Restoration Program. This action will enable the Environmental Restoration Program to design and implement consistent and coordinated final remedial actions for active and inactive LLBGs. Active and inactive burial grounds in the 200 West and 200 East Areas are commingled. This plan describes approaches that will be implemented during Interim Closure, Final Closure, and Institutional Control Periods to prepare LLBGs for surface barriers, and the construction of barriers, as well as the scope of inspection, monitoring and maintenance practices that will be performed during and after closure

  8. Neutron Diffraction of Aqueous Tetramethylammonium Chloride (TMA) Solutions and TMA Intercalated Swelling Clays Under Burial Conditions

    NASA Astrophysics Data System (ADS)

    Patel, R.; Howard, C. A.; Greenwell, C.; Youngs, T.; Soper, A. K.; Skipper, N. T.

    2014-12-01

    There is a need for the improvement and optimisation of clay swelling inhibitors for the enhancement of oil and gas exploration. The hydration region of both ions and the possibility of ion pairing in 1 molar aqueous solution of clay swelling inhibitor, tetramethylammonium chloride (TMACl), in D2O, under elevated hydrostatic-pressures and temperatures has been determined with unprecedented detail using a combination of neutron diffraction and small-angle scattering in conjunction with hydrogen/deuterium isotopic labeling. The O-H correlation function (H-bonds) for the water in the 1.0M solution is measured and compared with that for pure D2O. Also investigated is the effect of burial conditions on the d-spacing of TMA-intercalated vermiculite. Contrary to expectations, no aggregation of TMA ions due to hydrophobic interactions is observed, nor are any ionic pairs of TMA+ and Cl- at these burial conditions. The data revealed a more ordered water-water structure with the addition of TMACl from bulk D2O. There is no change in the hydration structure measured at the applied elevated conditions. This is in remarkable contrast to pure water at the same conditions which is well known to be compressible. The dry d-spacing of the TMA-exchanged Eucatex vermiculite is measured at 13.66 Å which increases to 14.03 Å with the addition of D2O. Beyond this, there is no change in d-spacing with increasing pressure and temperature indicating the strength of the TMA ions binding to the clay interlayers and therefore its performance as a clay-swelling inhibitor.

  9. Burial Level Change Defines a High Energetic Relevance for Protein Binding Interfaces.

    PubMed

    Li, Zhenhua; He, Ying; Wong, Limsoon; Li, Jinyan

    2015-01-01

    Protein-protein interfaces defined through atomic contact or solvent accessibility change are widely adopted in structural biology studies. But, these definitions cannot precisely capture energetically important regions at protein interfaces. The burial depth of an atom in a protein is related to the atom's energy. This work investigates how closely the change in burial level of an atom/residue upon complexation is related to the binding. Burial level change is different from burial level itself. An atom deeply buried in a monomer with a high burial level may not change its burial level after an interaction and it may have little burial level change. We hypothesize that an interface is a region of residues all undergoing burial level changes after interaction. By this definition, an interface can be decomposed into an onion-like structure according to the burial level change extent. We found that our defined interfaces cover energetically important residues more precisely, and that the binding free energy of an interface is distributed progressively from the outermost layer to the core. These observations are used to predict binding hot spots. Our approach's F-measure performance on a benchmark dataset of alanine mutagenesis residues is much superior or similar to those by complicated energy modeling or machine learning approaches. PMID:26357227

  10. Age-Associated Induction of Cell Membrane CD47 Limits Basal and Temperature-Induced Changes in Cutaneous Blood Flow

    PubMed Central

    Rogers, Natasha M.; Roberts, David D.; Isenberg, Jeffrey S.

    2012-01-01

    Objective We tested the hypothesis that the matricellular protein thrombospondin-1 (TSP1), through binding to and activation of the cell receptor CD47, inhibits basal and thermal-mediated cutaneous blood flow. Background Data Abnormal and decreased cutaneous blood flow in response to temperature changes or vasoactive agents is a feature of cardiovascular disease and aging. The reasons for decreased cutaneous blood flow remain incompletely understood. Further, a role for matricellular proteins in the regulation skin blood flow has never been proposed. Methods C57BL/6 wild type, TSP1- and CD47-null 12 and 72 week old male mice underwent analysis of skin blood flow (SkBF) via laser Doppler in response to thermal stress and vasoactive challenge. Results Young and aged TSP1- and CD47-null mice displayed enhanced basal and thermal sensitive SkFB changes compared to age matched wild type controls. Nitric oxide-mediated increases in SkBF were also greater in null mice. TSP1 and CD47 were expressed in skin from young wild type mice, and both were significantly upregulated in aged animals. Tissue 3',5'-cyclic guanosine monophosphate (cGMP), a potent vasodilator, was greater in skin samples from null mice compared to wild type regardless of age. Finally, treating wild type animals with a CD47 monoclonal antibody, that inhibits TSP1 activation of CD47, enhanced SkBF in both young and aged animals. Conclusions The above results suggest that secreted TSP1, via its cognate receptor CD47, acutely modulates SkBF. These data further support therapeutically targeting CD47 to mitigate age-associated loss of SkBF and maximize wound healing. PMID:23275312

  11. Morphogenetic evolution of the Têt river valley (eastern Pyrenees) using 10Be/21Ne cosmogenic burial dating

    NASA Astrophysics Data System (ADS)

    Sartégou, Amandine; Blard, Pierre-Henri; Braucher, Régis; Bourlès, Didier L.; Calvet, Marc; Zimmermann, Laurent; Tibari, Bouchaïb; Hez, Gabriel; Gunnell, Yanni; Aumaitre, Georges; Keddadouche, Karim

    2016-04-01

    The rates and chronologies of valley incision are closely modulated by the tectonic uplift of active mountain ranges and were controlled by repeated climate changes during the Quaternary. The continental collision between the Iberian and Eurasian plates induced a double vergence orogen, the Pyrenees, which has been considered as a mature mountain range in spite of significant seismicity (e.g. Chevrot et al., 2011) and evidence of neotectonics (e.g. Goula et al., 1999). Nevertheless, recent studies indicate that the range may have never reached a steady state (Ford et al., in press). One option for resolving this controversy is to quantify the incision rates since the Miocene by reconstructing the vertical movement of geometric markers such as fluvial terraces. However, the few available ages from the Pyrenean terrace systems do not exceed the middle Pleistocene. Thus, to enlarge the time span of this dataset, we studied alluvium-filled horizontal epiphreatic passages in limestone karstic networks. Such landforms are used as substitutes of fluvial terraces because they represent former valley floors (e.g. Palmer, 2007; Audra et al., 2013). They record the transient position of former local base levels during the process of valley deepening. The Têt river valley (southern Pyrenees) was studied near the Villefranche-de-Conflent limestone gorge where 8 cave levels have been recognized over a vertical height of 600 meters. Given that 26Al/10Be cosmogenic burial dating in this setting was limited to the last ~5 Ma (Calvet et al., 2015), here we used the cosmogenic 10Be/21Ne method in order to restore a more complete chronology of valley incision (e.g. Balco & Shuster, 2009; McPhilipps et al., 2016). Burial age results for alluvial deposits from 12 caves document incision rates since the Langhian (~14 Ma). Preliminary results indicate a history of valley deepening in successive stages. The data show a regular incision rate of 70-80 mm/a from the Langhian to the Messinian

  12. Comparison of different low-temperature aging protocols: its effects on the mechanical behavior of Y-TZP ceramics.

    PubMed

    Pereira, G K R; Muller, C; Wandscher, V F; Rippe, M P; Kleverlaan, C J; Valandro, L F

    2016-07-01

    This study evaluated the effect of different protocols of low-temperature degradation simulation on the mechanical behavior (structural reliability and flexural strength), the surface topography (roughness), and phase transformation of a Y-TZP ceramic. Disc-shaped specimens (1.2mm×12mm, Lava Frame, 3M ESPE, Seefeld, Germany) were manufactured according to ISO:6872-2008 and divided (n=30) according to the aging protocol executed: "Ctrl" - as-sintered - without any treatment; "Dist Water" - stored at distilled water at 37°C for 365 days; "MC" mechanical cycling into two steps: First - 200N, 2.2Hz for 2.000.000 cycles, Second - 450N, 10Hz for 1.000.000 cycles; "Aut" - steam autoclave at 134°C, 2bar (200kPa) for 20h; "Aut+MC"- Aut and MC methods. Roughness analysis (μm) showed, for Ra parameter, higher statistically significant values for Ctrl 0.68 (0.27), while for Rz parameter, the highest values were observed for Ctrl 4.43(1.53) and Aut 2.24 (0.62). Surface topography analysis showed that none aging method promoted surface alterations when compared to control group. Phase transformation analysis showed that all aging methods promoted an increase in m-phase content (Ctrl: 0.94%, Dist Water: 20.73%, MC: 9.47%, Aut: 53.33% and Aut+MC: 61.91%). Weibull Analysis showed higher statistical characteristic strength values for Aut (1033.36MPa) and Dist Water (1053.76MPa). No aging method promoted deleterious impact either on the biaxial flexural strengths or on the structural reliabilities (Weibull moduli). Also, none of the aging methods promoted reduction of Y-TZP mechanical properties; thus the development of new methodologies and the association between mechanical stimuli and hydrothermal degradation should be considered to better understand the mechanism of low-temperature degradation. PMID:26921592

  13. The microstructure and hydriding characteristics of high temperature aged U-13 at.%Nb alloy

    NASA Astrophysics Data System (ADS)

    Ji, Hefei; Shi, Peng; Li, Ruiwen; Jiang, Chunli; Yang, Jiangrong; Hu, Guichao

    2015-09-01

    Niobium as alloying element significantly improves physical and chemical properties of metallic uranium, exhibiting great application potential in uranium alloy materials. The corrosion resistance performance as well as the internal alloy phase structure of uranium-niobium alloy is closely related to aging processes. Microstructure and hydriding characteristics of the 400 °C/9 h + 500 °C/2 h aged uranium-13 at.% niobium alloys (U-13 at.%Nb) were investigated from the point of view of relationship between the microstructure and growth of the hydriding areas. The microstructure, morphology and composition of the alloy phases before and after the hydriding were well characterized by the laser scanning confocal microscopy (LSCM), scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. Experimental results indicated that the hydrogen preferentially reacted with the Nb-depleted phase α-like-U to form monolithic β-UH3Nbx, and the alloy microstructure played an important role in hydride growth.

  14. Recrystallization and aging effects associated with the high temperature deformation of waspaloy and inconel 718

    NASA Astrophysics Data System (ADS)

    Guimaraes, A. A.; Jonas, J. J.

    1981-09-01

    Cylindrical samples of Waspaloy and Inconel 718 were hot compressed, using a computerized Instron machine. The test program covered strain rates from 10•4 s•1 to 1 s•1 temperatures ranging from 875 °C to 1220 °C and deformations up to strains of 0.7. Interrupted tests were also carried out to determine the nature of the static softening and hardening processes. Dynamic recrystallization, partial or complete, was observed at temperatures above 950 °C. At 950 °C and below, dynamic recovery was the process controlling the deformation. Static softening was found to take place both by recovery and by recrystallization. Yield points were detected in Waspaloy under certain conditions as well as in Inconel 718. For Waspaloy the yield drops occurred in the vicinity of 1100 °C, and a deviation from the normal behavior in the stress-temperature curve was seen in the same temperature range. The mechanism responsible for the occurrence of the yield drops, which in turn is related to the deviation in the σ vsT curve, is believed to be short range ordering of the γ’ forming elements. For Inconel 718, elements such as Co, Cr and Fe may be causing short range ordering, but the locking mechanism may also be associated with the precipitation of carbides or other intermetallic phases on the dislocations.

  15. A burial cave in the western Aleutian Islands, Alaska.

    PubMed

    West, Dixie; Lefèvre, Christine; Corbett, Debra; Crockford, Susan

    2003-01-01

    During the 1998 field season, the Western Aleutians Archaeological and Paleobiological Project (WAAPP) team located a cave in the Near Islands, Alaska. Near the entrance of the cave, the team identified work areas and sleeping/sitting areas surrounded by cultural debris and animal bones. Human burials were found in the cave interior. In 2000, with permission from The Aleut Corporation, archaeologists revisited the site. Current research suggests three distinct occupations or uses for this cave. Aleuts buried their dead in shallow graves at the rear of the cave circa 1,200 to 800 years ago. Aleuts used the front of the cave as a temporary hunting camp as early as 390 years ago. Finally, Japanese and American military debris and graffiti reveal that the cave was visited during and after World War II. Russian trappers may have also taken shelter there 150 to 200 years ago. This is the first report of Aleut cave burials west of the Delarof Islands in the central Aleutians. PMID:21755641

  16. The Application of GPR in Florida for Detecting Forensic Burials

    SciTech Connect

    S. K. Koppenjan; J. J. Schultz; S. Ono; H. Lee

    2003-01-01

    A study was performed at the University of Florida to measure ground penetrating radar(GPR) performance for detecting forensic burials. In controlled scenarios, 24 burials were constructed with pig cadavers. Two soils were utilized to represent two of the most common soil orders in Florida: an Entisol and an Ultisol. Graves were monitored on a monthly basis for time periods up to 21 months with grid data acquired with pulsed and swept-frequency GPR systems incorporating several different frequency antennas. A small subset of the graves was excavated to assess decomposition and relate to the GPR images during the test. The grave anomalies in the GPR depth profiles became less distinctive over time due to body decomposition and settling of the disturbed soil (backfill) as it compacted. Soil type was a major factor. Grave anomalies became more difficult to recognize over time for deep targets that were within clay. Forensic targets that were in sandy soil were recognized for the duration of this study. Time elapsed imagery will be presented to elucidate the changes, or lack thereof, of grave anomalies over the duration of this study. Further analysis was performed using Synthetic Aperture Radar (SAR) reconstruction of images in 2-D and 3-D.

  17. Burial dolomitization of Lower Cambrian platform margin, Virginia

    SciTech Connect

    Barnaby, R.J.; Read, J.F.

    1989-03-01

    Shady Dolomite platform carbonates (Lower Cambrian) record several episodes of dolomite replacement and cementation during deep burial. Rare relict nonluminescent dolomite cores (zone 1) were replaced and overgrown by dark orange-red cathodoluminescent (CL) dolomite (zone 2A), the dominant replacement phase. Zone 2A dolomite was corroded, fractured, brecciated, and overgrown by Mississippi-Valley-type or lead-zinc minerals. Dark orange-red CL saddle dolomite (zone 2B) precipitated after mineralization and was fractured, corroded, and overgrown by bright orange-red CL saddle dolomite (zone 3). Cementation by later dark orange-red CL saddle dolomite (zone 4) was followed by quartz, calcite, and dedolomite. Only late-stage dolomite (zones 3 and 4) and calcite cement have elevated /sup 87/Sr//sup 86/Sr values (0.7103-0.7111) relative to marine carbonate and earlier dolomites (0.7090-0.7097), recording influx of radiogenic strontium-enriched fluids during late Paleozoic thrusting. Although the replacement dolomites are buried, it is unclear whether they replaced limestone or an unstable near-surface precursor dolomite. If a precursor dolomite were present, it was completely overprinted during burial diagenesis, preserving no trace of its initial composition.

  18. Genetic research at a fivefold children's burial from medieval Berlin.

    PubMed

    Rothe, Jessica; Melisch, Claudia; Powers, Natasha; Geppert, Maria; Zander, Judith; Purps, Josephine; Spors, Birgit; Nagy, Marion

    2015-03-01

    Berlin originated from the two twin cities Berlin and Cölln, which both were founded at the beginning of the 13th century. However the real date of their foundation as well as the origin of the first settlers is still unknown. On the Berlin site the historic city center is still visible in the Nikolaiviertel, but the medieval origin of Cölln disappeared almost completely. In 2007 a large scale excavation, which comprised an area of about 1700m(2) of the historical center of the St. Peters church, recovers the remains of Cölln's first citizens and span a period of 500 years of medieval population. Here we present the first genetic analysis of a fivefold children's burial from excavations in Berlin. The genetic data unveiled next to ancestry and eye color data also the kinship and the gender of the five individuals. Together with the archeological context the new gained information help to shed more light on the possible reasons for this burial. PMID:25466970

  19. Burial increases seed longevity of two Artemisia tridentata (Asteraceae) subspecies

    USGS Publications Warehouse

    Wijayratne, Upekala C.; Pyke, David A.

    2012-01-01

    Premise of the study: Seed longevity and persistence in soil seed banks may be especially important for population persistence in ecosystems where opportunities for seedling establishment and disturbance are unpredictable. The fire regime, an important driver of population dynamics in sagebrush steppe ecosystems, has been altered by exotic annual grass invasion. Soil seed banks may play an active role in postfire recovery of the foundation shrub Artemisia tridentata, yet conditions under which seeds persist are largely unknown. Methods: We investigated seed longevity of two Artemisia tridentata subspecies in situ by retrieving seed bags that were placed at varying depths over a 2 yr period. We also sampled naturally dispersed seeds in litter and soil immediately after seed dispersal and before flowering in subsequent seasons to estimate seed persistence. Key results: After 24 mo, seeds buried at least 3 cm below the soil surface retained 30–40% viability whereas viability of seeds on the surface and under litter declined to 0 and Artemisia tridentata has the potential to form a short-term soil seed bank that persists longer than has been commonly assumed, and that burial is necessary for seed longevity. Use of seeding techniques that promote burial of some seeds to aid in formation of a soil seed bank may increase restoration potential.

  20. Development and Application of a Paleomagnetic/Geochemical Method for Constraining the Timing of Burial Diagenetic and Fluid

    SciTech Connect

    Elmore, Richard D.; Engel, Michael H.

    2005-03-10

    Studies of diagenesis caused by fluid migration or other events are commonly hindered by a lack of temporal control. Our results to date demonstrate that a paleomagnetic/geochemical approach can be used to date fluid migration as well as burial diagenetic events. Our principal working hypothesis is that burial diagenetic processes (e.g., maturation of organic-rich sediments and clay diagenesis) and the migration of fluids can trigger the authigenesis of magnetic mineral phases. The ages of these events can be constrained by comparing chemical remanent magnetizations (CRMs) to independently established Apparent Polar Wander Paths. While geochemical (e.g. stable isotope and organic analyses) and petrographic studies provide important clues for establishing these relationships, the ultimate test of this hypothesis requires the application of independent dating methods to verify the paleomagnetic ages. Towards this end, we have used K-Ar dating of illitization as an alternative method for constraining the ages of magnetic mineral phases in our field areas.

  1. Evolution of stress and deformations in high-temperature polymer matrix composites during thermo-oxidative aging

    NASA Astrophysics Data System (ADS)

    Pochiraju, K. V.; Tandon, G. P.; Schoeppner, G. A.

    2008-03-01

    This paper presents a model-based analysis of thermo-oxidative behavior in high-temperature polymer matrix composite (HTPMC) materials. The thermo-oxidative behavior of the composite differs from that of the constituents as the composite microstructure, the fiber/matrix interphase/interface behavior and damage mechanisms introduce anisotropy in the diffusion and oxidation behavior. Three-dimensional Galerkin finite element methods (GFEM) that model the thermo-oxidative layer growth with time are used together with homogenization techniques to analyze lamina-scale behavior using representative volume elements (RVEs). Thermo-oxidation-induced shrinkage is characterized from dimensional changes observed during aging in inert (argon) and oxidative (air) environments. Temperature-dependent macro-scale (bulk) mechanical testing and nano-indentation techniques are used for characterizing the effect of oxidative aging on modulus evolution. The stress and deformation fields in a single ply unidirectional lamina are studied using coupled oxidation evolution and non-linear elastic deformation analyses. Deformation and stress states are shown as a function of the aging time. While the thermo-oxidative processes are controlled by diffusion phenomenon in neat resin, the onset and propagation of damage determines the oxidative response of an HTPMC.

  2. Influence of ageing on the quasistatic fracture toughness of an SS 316(N) weld at ambient and elevated temperatures

    NASA Astrophysics Data System (ADS)

    Sasikala, G.; Ray, S. K.

    2011-01-01

    The leak before break analysis of SS 316L(N) components of the prototype fast breeder reactor requires the elastic plastic fracture toughness parameter J for 0.2 mm crack extension, J0.2, especially for the welds, at the operating temperatures. The J- R curves for the welds produced using the consumable developed by Indira Gandhi Centre for Atomic Research, were determined in the as-welded condition as well as after thermal ageing (923 K/4200 h) conditions at 298 K and 643 K, using unloading compliance method for 298 K and normalization method for 643 K. The aged material exhibited pop-in crack extensions of magnitudes that, according to ASTM E1820 standard, could be ignored for multi-specimen data analysis for determining J0.2. Therefore, for this condition, J nom- Δ a curves were established using the multiple specimen method and also single specimen normalization method; for the latter, a modification earlier developed by the authors for accounting for small pop-in crack extensions was used. The value of J0.2 from both methods showed excellent reproducibility. Ageing is seen to reduce the toughness of this material considerably at both the testing temperatures.

  3. Groundwater noble gas, age, and temperature signatures in an Alpine watershed: Valuable tools in conceptual model development

    USGS Publications Warehouse

    Manning, A.H.; Caine, J.S.

    2007-01-01

    [1] Bedrock groundwater in alpine watersheds is poorly understood, mainly because of a scarcity of wells in alpine settings. Groundwater noble gas, age, and temperature data were collected from springs and wells with depths of 3-342 m in Handcart Gulch, an alpine watershed in Colorado. Temperature profiles indicate active groundwater circulation to a maximum depth (aquifer thickness) of about 200 m, or about 150 m below the water table. Dissolved noble gas data show unusually high excess air concentrations (>0.02 cm3 STP/g, ??Ne > 170%) in the bedrock, consistent with unusually large seasonal water table fluctuations (up to 50 m) observed in the upper part of the watershed. Apparent 3H/3He ages are positively correlated with sample depth and excess air concentrations. Integrated samples were collected from artesian bedrock wells near the trunk stream and are assumed to approximate flow-weighted samples reflecting bedrock aquifer mean residence times. Exponential mean ages for these integrated samples are remarkably consistent along the stream, four of five being from 8 to 11 years. The tracer data in combination with other hydrologic and geologic data support a relatively simple conceptual model of groundwater flow in the watershed in which (1) permeability is primarily a function of depth; (2) water table fluctuations increase with distance from the stream; and (3) recharge, aquifer thickness, and porosity are relatively uniform throughout the watershed in spite of the geological complexity of the Proterozoic crystalline rocks that underlie it. Copyright 2007 by the American Geophysical Union.

  4. Groundwater noble gas, age, and temperature signatures in an Alpine watershed: Valuable tools in conceptual model development

    NASA Astrophysics Data System (ADS)

    Manning, Andrew H.; Caine, Jonathan Saul

    2007-04-01

    Bedrock groundwater in alpine watersheds is poorly understood, mainly because of a scarcity of wells in alpine settings. Groundwater noble gas, age, and temperature data were collected from springs and wells with depths of 3-342 m in Handcart Gulch, an alpine watershed in Colorado. Temperature profiles indicate active groundwater circulation to a maximum depth (aquifer thickness) of about 200 m, or about 150 m below the water table. Dissolved noble gas data show unusually high excess air concentrations (>0.02 cm3 STP/g, ΔNe > 170%) in the bedrock, consistent with unusually large seasonal water table fluctuations (up to 50 m) observed in the upper part of the watershed. Apparent 3H/3He ages are positively correlated with sample depth and excess air concentrations. Integrated samples were collected from artesian bedrock wells near the trunk stream and are assumed to approximate flow-weighted samples reflecting bedrock aquifer mean residence times. Exponential mean ages for these integrated samples are remarkably consistent along the stream, four of five being from 8 to 11 years. The tracer data in combination with other hydrologic and geologic data support a relatively simple conceptual model of groundwater flow in the watershed in which (1) permeability is primarily a function of depth; (2) water table fluctuations increase with distance from the stream; and (3) recharge, aquifer thickness, and porosity are relatively uniform throughout the watershed in spite of the geological complexity of the Proterozoic crystalline rocks that underlie it.

  5. A multi-proxy reconstruction of environmental change spanning the last 37,000 years from Burial Lake, Arctic Alaska

    NASA Astrophysics Data System (ADS)

    Finkenbinder, M. S.; Abbott, M. B.; Finney, B. P.; Stoner, J. S.; Dorfman, J. M.

    2015-10-01

    Dryas from Burial Lake sediments contrasts with some paleorecords showing cooler temperatures and/or dry conditions in northern Alaska at this time. Peak levels of sediment organic content and terrestrial productivity at Burial Lake between 10,500 and 9900 cal yr BP coincide with the early Holocene summer insolation maxima, which likely represents summertime warming and an enhanced flux of watershed derived organic matter from permafrost degradation. The remainder of the Holocene (since 8800 cal yr BP) at Burial Lake is characterized by relatively high and stable lake levels, landscape stabilization, and relatively high and variable levels of aquatic productivity.

  6. Impact of extreme temperatures on daily mortality in Madrid (Spain) among the 45-64 age-group

    NASA Astrophysics Data System (ADS)

    Díaz, Julio; Linares, Cristina; Tobías, Aurelio

    2006-07-01

    This paper analyses the relationship between extreme temperatures and mortality among persons aged 45-64 years. Daily mortality in Madrid was analysed by sex and cause, from January 1986 to December 1997. Quantitative analyses were performed using generalised additive models, with other covariables, such as influenza, air pollution and seasonality, included as controls. Our results showed that impact on mortality was limited for temperatures ranging from the 5th to the 95th percentiles, and increased sharply thereafter. During the summer period, the effect of heat was detected solely among males in the target age group, with an attributable risk (AR) of 13.3% for circulatory causes. Similarly, NO2 concentrations registered the main statistically significant associations in females, with an AR of 15% when circulatory causes were considered. During winter, the impact of cold was exclusively observed among females having an AR of 7.7%. The magnitude of the AR indicates that the impact of extreme temperature is by no means negligible.

  7. Aggravated efficiency droop in vertical-structured gallium nitride light-emitting diodes induced by high temperature aging

    NASA Astrophysics Data System (ADS)

    Liu, Lilin; Yang, Jianfu; Ling, Minjie; Zhong, Jianwei; Teng, Dongdong; Wang, Gang

    2013-02-01

    The present work demonstrates that aging at higher temperatures significantly aggravates "efficiency droop" in the n-side-up vertical-structured GaN-based light-emitting diodes (LEDs). The observed luminous efficiency droop is over 40% at the measuring current of 350 mA. This phenomenon closely relates with creeping of Au80Sn20 eutectic bonds. On one hand, the plastic deformation accumulated during creeping at higher aging temperatures will make the LED epilayers tensile strained at room temperature. The tensile strain induces a change of the internal quantum efficiency (IQE). The maximum variation of IQE related with strain states was around 20%. On the other hand, creeping under the thermal-mismatching induced tensile stress activates voids' nucleation and growth in the solder bonds. The distribution profile of voids in solder bonds will be mapped on the multiple quantum-well structure in vertical-structured LED chips. Local current densities can be much higher than the average current density used in the calculation of LED's efficiencies. Therefore, the efficiency roll-off value will shift toward the smaller bias direction and the total internal quantum efficiency will decrease as current increases.

  8. Impact of extreme temperatures on daily mortality in Madrid (Spain) among the 45-64 age-group.

    PubMed

    Díaz, Julio; Linares, Cristina; Tobías, Aurelio

    2006-07-01

    This paper analyses the relationship between extreme temperatures and mortality among persons aged 45-64 years. Daily mortality in Madrid was analysed by sex and cause, from January 1986 to December 1997. Quantitative analyses were performed using generalised additive models, with other covariables, such as influenza, air pollution and seasonality, included as controls. Our results showed that impact on mortality was limited for temperatures ranging from the 5th to the 95th percentiles, and increased sharply thereafter. During the summer period, the effect of heat was detected solely among males in the target age group, with an attributable risk (AR) of 13.3% for circulatory causes. Similarly, NO(2) concentrations registered the main statistically significant associations in females, with an AR of 15% when circulatory causes were considered. During winter, the impact of cold was exclusively observed among females having an AR of 7.7%. The magnitude of the AR indicates that the impact of extreme temperature is by no means negligible. PMID:16718468

  9. Effect of High Temperature Aging on the Corrosion Resistance of Iron Based Amorphous Alloys

    SciTech Connect

    Day, S D; Haslam, J J; Farmer, J C; Rebak, R B

    2007-08-10

    Iron-based amorphous alloys can be more resistant to corrosion than polycrystalline materials of similar compositions. However, when the amorphous alloys are exposed to high temperatures they may recrystallize (or devitrify) thus losing their resistance to corrosion. Four different types of amorphous alloys melt spun ribbon specimens were exposed to several temperatures for short periods of time. The resulting corrosion resistance was evaluated in seawater at 90 C and compared with the as-prepared ribbons. Results show that the amorphous alloys can be exposed to 600 C for 1-hr. without losing the corrosion resistance; however, when the ribbons were exposed at 800 C for 1-hr. their localized corrosion resistance decreased significantly.

  10. Effects of aging time and temperature of Fe-1wt.%Cu on magnetic Barkhausen noise and FORC

    NASA Astrophysics Data System (ADS)

    Saleh, Muad; Cao, Yue; Edwards, Danny J.; Ramuhalli, Pradeep; Johnson, Bradley R.; McCloy, John S.

    2016-05-01

    Magnetic Barkhausen noise (MBN), hysteresis measurements, first order reversal curves (FORC), Vickers microhardness, and Transmission Electron Microscopy (TEM) analyses were performed on Fe-1wt.%Cu (Fe-Cu) samples isothermally aged at 700°C for 0.5 - 25 hours to obtain samples with different sized Cu precipitates and dislocation structures. Fe-Cu is used to simulate the thermal and irradiation-induced defects in copper-containing nuclear reactor materials such as cooling system pipes and pressure vessel materials. The sample series showed an initial increase followed by a decrease in hardness and coercivity with aging time, which is explained by Cu precipitates formation and growth as observed by TEM measurements. Further, the MBN envelope showed a continuous decrease in its magnitude and the appearance of a second peak with aging. Also, FORC diagrams showed multiple peaks whose intensity and location changed for different aging time. The changes in FORC diagrams are attributed to combined changes of the magnetic behavior due to Cu precipitate characteristics and dislocation structure. A second series of samples aged at 850°C, which is above the solid solution temperature of Fe-Cu, was studied to isolate the effects of dislocations. These samples showed a continuous decrease in MBN amplitude with aging time although the coercivity and hardness did not change significantly. The decrease of MBN amplitude and the appearance of the second MBN envelope peak are attributed to the changes in dislocation density and structure. This study shows that the effect of dislocations on MBN and FORC of Fe-Cu materials can vary significantly and should be considered in interpreting magnetic signatures.

  11. Effect of the severe plastic deformation and aging temperature on the strengthening, structure, and wear resistance of a beryllium bronze

    NASA Astrophysics Data System (ADS)

    Korshunov, L. G.; Korznikov, A. V.; Chernenko, N. L.

    2011-04-01

    The effect of the aging temperature, severe plastic deformation by equal-channel angular (ECA) pressing at 400°C, and subsequent aging on the rate of wear, friction coefficient, and microhardness of a commercial beryllium bronze Br.B2 quenched from 800°C has been investigated. The bronze structure before and after tribological tests has been studied with the help of metallographic and electron-microscopic methods of analysis. It has been shown that tempering (aging) of the bronze at 250-400°C for 3 h leading to a sharp growth of the hardness substantially increases the wear rate of the bronze in pair with the steel 45 under the conditions of both dry and boundary sliding friction. The cause of this is a decrease in the toughness of the surface layer of the bronze due to the precipitation of particles of the strengthening γ' phase (CuBe) from the α solid solution. Severe plastic deformation (ECA pressing) markedly enhances the wear resistance of the bronze subjected to subsequent aging at 250-400°C. This is because ECA pressing favors the formation of an extremely dispersed nanocrystalline structure with α-phase crystals 40-50 nm in size at the wear surface of the bronze; whereas in the friction zone of the quenched bronze or the quenched and aged bronze, there arises a significantly less dispersed structure with matrix crystals to 300 nm in size. It has been assumed that under conditions of the rotational mechanism of plastic deformation operating upon sliding friction in the near-surface layer of the bronze, the increase in dispersity of its structure attained by using ECA pressing enhances the toughness and, correspondingly, wear resistance of the aged bronze.

  12. Minimal impact of age and housing temperature on the metabolic phenotype of Acc2-/- mice.

    PubMed

    Brandon, Amanda E; Stuart, Ella; Leslie, Simon J; Hoehn, Kyle L; James, David E; Kraegen, Edward W; Turner, Nigel; Cooney, Gregory J

    2016-03-01

    An important regulator of fatty acid oxidation (FAO) is the allosteric inhibition of CPT-1 by malonyl-CoA produced by the enzyme acetyl-CoA carboxylase 2 (ACC2). Initial studies suggested that deletion of Acc2 (Acacb) increased fat oxidation and reduced adipose tissue mass but in an independently generated strain of Acc2 knockout mice we observed increased whole-body and skeletal muscle FAO and a compensatory increase in muscle glycogen stores without changes in glucose tolerance, energy expenditure or fat mass in young mice (12-16 weeks). The aim of the present study was to determine whether there was any effect of age or housing at thermoneutrality (29 °C; which reduces total energy expenditure) on the phenotype of Acc2 knockout mice. At 42-54 weeks of age, male WT and Acc2(-/-) mice had similar body weight, fat mass, muscle triglyceride content and glucose tolerance. Consistent with younger Acc2(-/-) mice, aged Acc2(-/-) mice showed increased whole-body FAO (24 h average respiratory exchange ratio=0.95±0.02 and 0.92±0.02 for WT and Acc2(-/-) mice respectively, P<0.05) and skeletal muscle glycogen content (+60%, P<0.05) without any detectable change in whole-body energy expenditure. Hyperinsulinaemic-euglycaemic clamp studies revealed no difference in insulin action between groups with similar glucose infusion rates and tissue glucose uptake. Housing Acc2(-/-) mice at 29 °C did not alter body composition, glucose tolerance or the effects of fat feeding compared with WT mice. These results confirm that manipulation of Acc2 may alter FAO in mice, but this has little impact on body composition or insulin action. PMID:26668208

  13. Effect of Relative Humidity and Temperature on Photochemical Aging of Secondary Organic Aerosols

    NASA Astrophysics Data System (ADS)

    Nizkorodov, S.; Brady, M. V.; Hinks, M. L.; Lignell, H.; Bertram, A. K.; Song, M.; Laskin, A.; Laskin, J.; Lin, P.

    2014-12-01

    The viscosity of secondary organic aerosol material (SOM) is known to depend sensitively on both temperature and relative humidity (RH). This work investigates the effect of these two important environmental variables on photochemical processes occurring inside model SOM. The experiments are designed to test the hypothesis that an increased SOM viscosity, resulting from either lower temperatures or decreased RH, should slow down the rates of photochemical processes in the organic matrix by constraining molecular motion inside the matrix. Photolysis of a probe molecule, 2,4-dinitrophenol, dispersed in SOM made produced through oxidation of alpha-pinene and limonene by ozone is investigated with absorption spectroscopy methods under controlled humidity and temperature. Viscosity of SOM is directly measured using "bead-mobility" technique and "poke-flow" techniques. Finally, the products of 2,4-dinitrophenol are analyzed by liquid chromatography high resolution mass spectrometry methods. The experiments suggest that the presence of water strongly affects photodegradation rates of organic compounds contained in the SOM matrix. Given the paramount role of photochemistry in driving the chemical reactions in the environment, these results will have significant implications for predicting lifetimes of photolabile atmospheric organic compounds trapped in organic particles.

  14. Dynamics of Carbon Burial in the Coastal Oceans through the Paleocene-Eocene Thermal Maximum

    NASA Astrophysics Data System (ADS)

    Schneider-Mor, A.; Bowen, G. J.

    2008-12-01

    Climatic recovery from the Paleocene-Eocene boundary thermal maximum (PETM) involved the rapid burial of thousands of petagrams of carbon, a significant fraction of which may have been sequestered in marginal marine sediments. This burial flux may have been modulated by changes in climate, biology, sea level, and sediment flux, but the primary pathways and controls on excess carbon burial have remained speculative to this point. Using the global PETM carbon isotope excursion and C/N ratios as tracer of organic carbon source, we investigated preservation of organic carbon through the PETM as particulate organic carbon (POC) and mineral-bound carbon (MBC) at three coastal ocean sites (Tawanui, New Zealand; IODP leg 302, Arctic Ocean; and Wilson Lake, NJ, USA). We show that an increase in total organic carbon burial during the PETM is dominated by burial of young (<10,000 year old), land-derived POC, but that elevated POC burial was limited to sites with high sedimentation rates through the event (ca. 5 cm/kyr). In contrast, MBC sources were more variable, both among sites and through the PETM, and although there was no conclusive evidence for reburial of kerogen-derived MBC at the study sites the carbon isotope data suggest that a fraction of the MBC at each site may have had a long (>10,000 years) residence time prior to burial. MBC dominated the organic burial flux only at the low sedimentation-rate site (Tawanui), but also contributed significantly to changes in total burial at the Arctic site where bottom water anoxia or suboxia has been inferred during the PETM. Our results demonstrate that changes in total carbon burial rates in marginal marine sediments were determined by decoupled responses of the POC and MBC burial pathways that varied substantially among locations, and that the strongest feedbacks on PETM climate involved changes in the transfer of sediment and particulate organic carbon from the continents to the coastal oceans.

  15. Microstructural behavior of iron and bismuth added Sn-1Ag-Cu solder under elevated temperature aging

    NASA Astrophysics Data System (ADS)

    Ali, Bakhtiar; Sabri, Mohd Faizul Mohd; Jauhari, Iswadi

    2016-07-01

    An extensive study was done to investigate the microstructural behavior of iron (Fe) and bismuth (Bi) added Sn-1Ag-0.5Cu (SAC105) under severe thermal aging conditions. The isothermal aging was done at 200 °C for 100 h, 200 h, and 300 h. Optical microscopy with cross-polarized light revealed that the grain size significantly reduces with Fe/Bi addition to the base alloy SAC105 and remains literally the same after thermal aging. The micrographs of field emission scanning electron microscopy (FESEM) with backscattered electron detector and their further analysis via imageJ software indicated that Fe/Bi added SAC105 showed a significant reduction in the IMCs size (Ag3Sn and Cu6Sn5), especially the Cu6Sn5 IMCs, as well as β-Sn matrix and a refinement in the microstructure, which is due to the presence of Bi in the alloys. Moreover, their microstructure remains much more stable under severe thermal aging conditions, which is because of the presence of both Fe and Bi in the alloy. The microstructural behavior suggests that Fe/Bi modified SAC105 would have much improved reliability under severe thermal environments. These modified alloys also have relatively low melting temperature and low cost.

  16. Thawing of permafrost may disturb historic cattle burial grounds in East Siberia.

    PubMed

    Revich, Boris A; Podolnaya, Marina A

    2011-01-01

    Climate warming in the Arctic may increase the risk of zoonoses due to expansion of vector habitats, improved chances of vector survival during winter, and permafrost degradation. Monitoring of soil temperatures at Siberian cryology control stations since 1970 showed correlations between air temperatures and the depth of permafrost layer that thawed during summer season. Between 1900s and 1980s, the temperature of surface layer of permafrost increased by 2-4°C; and a further increase of 3°C is expected. Frequent outbreaks of anthrax caused death of 1.5 million deer in Russian North between 1897 and 1925. Anthrax among people or cattle has been reported in 29,000 settlements of the Russian North, including more than 200 Yakutia settlements, which are located near the burial grounds of cattle that died from anthrax. Statistically significant positive trends in annual average temperatures were established in 8 out of 17 administrative districts of Yakutia for which sufficient meteorological data were available. At present, it is not known whether further warming of the permafrost will lead to the release of viable anthrax organisms. Nevertheless, we suggest that it would be prudent to undertake careful monitoring of permafrost conditions in all areas where an anthrax outbreak had occurred in the past. PMID:22114567

  17. Thawing of permafrost may disturb historic cattle burial grounds in East Siberia

    PubMed Central

    Revich, Boris A.; Podolnaya, Marina A.

    2011-01-01

    Climate warming in the Arctic may increase the risk of zoonoses due to expansion of vector habitats, improved chances of vector survival during winter, and permafrost degradation. Monitoring of soil temperatures at Siberian cryology control stations since 1970 showed correlations between air temperatures and the depth of permafrost layer that thawed during summer season. Between 1900s and 1980s, the temperature of surface layer of permafrost increased by 2–4°C; and a further increase of 3°C is expected. Frequent outbreaks of anthrax caused death of 1.5 million deer in Russian North between 1897 and 1925. Anthrax among people or cattle has been reported in 29,000 settlements of the Russian North, including more than 200 Yakutia settlements, which are located near the burial grounds of cattle that died from anthrax. Statistically significant positive trends in annual average temperatures were established in 8 out of 17 administrative districts of Yakutia for which sufficient meteorological data were available. At present, it is not known whether further warming of the permafrost will lead to the release of viable anthrax organisms. Nevertheless, we suggest that it would be prudent to undertake careful monitoring of permafrost conditions in all areas where an anthrax outbreak had occurred in the past. PMID:22114567

  18. A new model for the estimation of time of death from vitreous potassium levels corrected for age and temperature.

    PubMed

    Zilg, B; Bernard, S; Alkass, K; Berg, S; Druid, H

    2015-09-01

    Analysis of potassium concentration in the vitreous fluid of the eye is frequently used by forensic pathologists to estimate the postmortem interval (PMI), particularly when other methods commonly used in the early phase of an investigation can no longer be applied. The postmortem rise in vitreous potassium has been recognized for several decades and is readily explained by a diffusion of potassium from surrounding cells into the vitreous fluid. However, there is no consensus regarding the mathematical equation that best describes this increase. The existing models assume a linear increase, but different slopes and starting points have been proposed. In this study, vitreous potassium levels, and a number of factors that may influence these levels, were examined in 462 cases with known postmortem intervals that ranged from 2h to 17 days. We found that the postmortem rise in potassium followed a non-linear curve and that decedent age and ambient temperature influenced the variability by 16% and 5%, respectively. A long duration of agony and a high alcohol level at the time of death contributed less than 1% variability, and evaluation of additional possible factors revealed no detectable impact on the rise of vitreous potassium. Two equations were subsequently generated, one that represents the best fit of the potassium concentrations alone, and a second that represents potassium concentrations with correction for decedent age and/or ambient temperature. The former was associated with narrow confidence intervals in the early postmortem phase, but the intervals gradually increased with longer PMIs. For the latter equation, the confidence intervals were reduced at all PMIs. Therefore, the model that best describes the observed postmortem rise in vitreous potassium levels includes potassium concentration, decedent age, and ambient temperature. Furthermore, the precision of these equations, particularly for long PMIs, is expected to gradually improve by adjusting the

  19. 26Al/10Be burial dating of Xujiayao-Houjiayao site in Nihewan Basin, northern China.

    PubMed

    Tu, Hua; Shen, Guanjun; Li, Haixu; Xie, Fei; Granger, Darryl E

    2015-01-01

    The Xujiayao-Houjiayao site in Nihewan Basin is among the most important Paleolithic sites in China for having provided a rich collection of hominin and mammalian fossils and lithic artifacts. Based on biostratigraphical correlation and exploratory results from a variety of dating methods, the site has been widely accepted as early Upper Pleistocene in time. However, more recent paleomagnetic analyses assigned a much older age of ∼500 ka (thousand years). This paper reports the application of 26Al/10Be burial dating as an independent check. Two quartz samples from a lower cultural horizon give a weighted mean age of 0.24 ± 0.05 Ma (million years, 1σ). The site is thus younger than 340 ka at 95% confidence, which is at variance with the previous paleomagnetic results. On the other hand, our result suggests an age of older than 140 ka for the site's lower cultural deposits, which is consistent with recent post-infrared infrared stimulated luminescence (pIR-IRSL) dating at 160-220 ka. PMID:25706272

  20. 26Al/10Be Burial Dating of Xujiayao-Houjiayao Site in Nihewan Basin, Northern China

    PubMed Central

    Tu, Hua; Shen, Guanjun; Li, Haixu; Xie, Fei; Granger, Darryl E.

    2015-01-01

    The Xujiayao-Houjiayao site in Nihewan Basin is among the most important Paleolithic sites in China for having provided a rich collection of hominin and mammalian fossils and lithic artifacts. Based on biostratigraphical correlation and exploratory results from a variety of dating methods, the site has been widely accepted as early Upper Pleistocene in time. However, more recent paleomagnetic analyses assigned a much older age of ∼500 ka (thousand years). This paper reports the application of 26Al/10Be burial dating as an independent check. Two quartz samples from a lower cultural horizon give a weighted mean age of 0.24 ± 0.05 Ma (million years, 1σ). The site is thus younger than 340 ka at 95% confidence, which is at variance with the previous paleomagnetic results. On the other hand, our result suggests an age of older than 140 ka for the site’s lower cultural deposits, which is consistent with recent post-infrared infrared stimulated luminescence (pIR-IRSL) dating at 160–220 ka. PMID:25706272

  1. In Situ GISAXS investigation of low-temperature aging in oriented surfactant-mesostructured titania thin films

    DOE PAGESBeta

    Nagpure, Suraj; Das, Saikat; Garlapalli, Ravinder K.; Strzalka, Joseph; Rankin, Stephen E.

    2015-09-11

    In this study, the mechanism of forming orthogonally oriented hexagonal close packed (o-HCP) mesostructures during aging of surfactant-templated titania thin films is elucidated using in situ grazing incidence small-angle x-ray scattering (GISAXS) in a controlled-environment chamber. To promote orthogonal orientation, glass slides are modified with crosslinked Pluronic P123, to provide surfaces chemically neutral towards both blocks of mesophase template P123. At 4 °C and 80% RH, the o-HCP mesophase emerges in thin (~60 nm) films by a direct disorder-to-order transition, with no intermediate ordered mesophase. The Pluronic/titania o-HCP GISAXS intensity emerges only after ~10-12 minutes, much slower than previously reportedmore » for smallmolecule surfactants. The Avrami model applied to the data suggests 2D growth with nucleation at the start of the process with a half-life of 39.7 minutes for the aging time just after the induction period of 7 minutes followed by a period consistent with 1D growth kinetics. Surprisingly, films that are thicker (~250 nm) or cast on unmodified slides form o-HCP mesophase domains, but by a different mechanism (2D growth with continuous nucleation) with faster and less complete orthogonal alignment. Thus, the o-HCP mesophase is favored not only 2 by modifying the substrate, but also by aging at 4 °C, which is below the lower consolute temperature (LCST) of the poly(propylene oxide) block of P123. Consistent with this, in situ GISAXS shows that films aged at room temperature (above the LCST of the PPO block) have randomly oriented HCP mesostructure.« less

  2. Time-capsule concretions: Unlocking burial diagenetic processes in the Mancos Shale using carbonate clumped isotopes

    NASA Astrophysics Data System (ADS)

    Dale, Annabel; John, Cédric M.; Mozley, Peter S.; Smalley, P. C.; Muggeridge, Ann H.

    2014-05-01

    Septarian carbonate concretions contain carbonate precipitated during progressive growth of the concretion and subsequent fracture-filling. As such, they have been used to track variations in δ13C and δ18O of pore waters during diagenesis and to define diagenetic zones in clastic rocks. However, the δ18O value of the carbonate is dependent on precipitation temperature and the δ18O value of the pore fluid from which it precipitated. Interpretations must assume one of these parameters, both of which are highly variable through time in diagenetic settings. Carbonate clumped isotopes of the cement can provide independent estimates of temperature of precipitation, allowing the pore-water δ18O to be back-calculated. Here, we use this technique on carbonate concretions and fracture fills of the Upper Cretaceous Prairie Canyon Member, Mancos Shale, Colorado. We sampled concretions from two permeable horizons separated by a 5 m shale layer, with one permeable horizon containing concretions with septarian fractures. We show cores precipitated at cooler temperatures (31 °C, ˜660 m burial depth) than the rims (68 °C (˜1980 m burial depth) and relate that to the δ13Ccarbonate values to suggest the concretion core precipitated in the methanogenic zone, with increasing input from thermogenically produced CO2. The two concretion-bearing horizons have different back-calculated δ18Oporewater values (mean -2.65‰ and 1.13‰ VSMOW) for cements formed at the same temperature and similar δ13C values, suggesting the shale layer present between the two horizons acted as a barrier to fluid mixing. Additionally, the δ18Ocarbonate of the septarian fractures (-13.8‰ VPBD) are due to precipitation at high temperatures (102 to 115 °C) from a fluid with a mean δ18Oporewater of 0.32‰ (VSMOW). Therefore, we can tie in the cementation history of the formation to temporal and spatial variations in δ18Oporewater.

  3. Literature Review of the Effects of Radiation and Temperature on the Aging of Concrete

    SciTech Connect

    D. L. Fillmore

    2004-09-01

    The open literature and accessible United States Department of Energy-sponsored reports were reviewed for the effects of radiation and temperature on concrete. No effects of radiation were found for exposures less than 1010 neutron/cm2 or 1010 Gy gamma for periods less than 50 years. Reductions in compressive and tensile strength and a marked increase in volume are reported for exposures greater than 1020 neutron/cm2 or 1010 rads of gamma. There are conflicting reports of damage for doses in the middle ranges.

  4. 618-10 Burial Ground Trench Remediation and 618-10 and 618-11 Burial Ground Nonintrusive Characterization of Vertical Pipe Units Lessons Learned

    SciTech Connect

    Darby, J. W.

    2012-06-28

    A “lessons learned” is a noteworthy practice or innovative approach that is captured and shared to promote repeat application, or an adverse work practice/experience that is captured and shared to avoid reoccurrence. This document provides the lessons learned identified by the 618-10 Burial Ground trench remediation and the 618-10 and 618-11 Burial Ground nonintrusive characterization of the vertical pipe units (VPUs).

  5. 40Ar/39Ar impact ages and time-temperature argon diffusion history of the Bunburra Rockhole anomalous basaltic achondrite

    NASA Astrophysics Data System (ADS)

    Jourdan, Fred; Benedix, Gretchen; Eroglu, Ela.; Bland, Phil. A.; Bouvier, Audrey.

    2014-09-01

    The Bunburra Rockhole meteorite is a brecciated anomalous basaltic achondrite containing coarse-, medium- and fine-grained lithologies. Petrographic observations constrain the limited shock pressure to between ca. 10 GPa and 20 GPa. In this study, we carried out nine 40Ar/39Ar step-heating experiments on distinct single-grain fragments extracted from the coarse and fine lithologies. We obtained six plateau ages and three mini-plateau ages. These ages fall into two internally concordant populations with mean ages of 3640 ± 21 Ma (n = 7; P = 0.53) and 3544 ± 26 Ma (n = 2; P = 0.54), respectively. Based on these results, additional 40Ar/39Ar data of fusion crust fragments, argon diffusion modelling, and petrographic observations, we conclude that the principal components of the Bunburra Rockhole basaltic achondrite are from a melt rock formed at ∼3.64 Ga by a medium to large impact event. The data imply that this impact generated high enough energy to completely melt the basaltic target rock and reset the Ar systematics, but only partially reset the Pb-Pb age. We also conclude that a complete 40Ar∗ resetting of pyroxene and plagioclase at this time could not have been achieved at solid-state conditions. Comparison with a terrestrial analog (Lonar crater) shows that the time-temperature conditions required to melt basaltic target rocks upon impact are relatively easy to achieve. Ar data also suggest that a second medium-size impact event occurred on a neighbouring part of the same target rock at ∼3.54 Ga. Concordant low-temperature step ages of the nine aliquots suggest that, at ∼3.42 Ga, a third smaller impact excavated parts of the ∼3.64 Ga and ∼3.54 Ga melt rocks and brought the fragments together. The lack of significant impact activity after 3.5 Ga, as recorded by the Bunburra Rockhole suggests that (1) either the meteorite was ejected in a small secondary parent body where it resided untouched by large impacts, or (2) it was covered by a porous heat

  6. 38 CFR 3.1603 - Authority for burial of certain unclaimed bodies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... certain unclaimed bodies. 3.1603 Section 3.1603 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Burial Benefits § 3.1603 Authority for burial of certain unclaimed bodies. If the body of a deceased veteran is unclaimed, there being no relatives or friends to claim the...

  7. 38 CFR 3.1603 - Authority for burial of certain unclaimed bodies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... certain unclaimed bodies. 3.1603 Section 3.1603 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Burial Benefits § 3.1603 Authority for burial of certain unclaimed bodies. If the body of a deceased veteran is unclaimed, there being no relatives or friends to claim the...

  8. 38 CFR 3.1603 - Authority for burial of certain unclaimed bodies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... certain unclaimed bodies. 3.1603 Section 3.1603 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Burial Benefits § 3.1603 Authority for burial of certain unclaimed bodies. If the body of a deceased veteran is unclaimed, there being no relatives or friends to claim the...

  9. 38 CFR 3.1603 - Authority for burial of certain unclaimed bodies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... certain unclaimed bodies. 3.1603 Section 3.1603 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Burial Benefits § 3.1603 Authority for burial of certain unclaimed bodies. If the body of a deceased veteran is unclaimed, there being no relatives or friends to claim the...

  10. Burial affects the biogeochemistry of headwater streams in a midwestern US metropolitan area - slides

    EPA Science Inventory

    Nitrogen (N) retention in stream networks is an important ecosystem service that may be affected by the widespread burial of headwater streams in urban basins. Urban stream burial has only recently been recognized by ecologists as a regional environmental impact and little resea...

  11. Burial affects the biogeochemistry of headwater streams in a midwestern US metropolitan area

    EPA Science Inventory

    Nitrogen (N) retention in stream networks is an important ecosystem service that may be affected by the widespread burial of headwater streams in urban basins. Urban stream burial has only recently been recognized by ecologists and little research has addressed the extent to whi...

  12. Cleanup Verification Package for the 118-C-1, 105-C Solid Waste Burial Ground

    SciTech Connect

    M. J. Appel and J. M. Capron

    2007-07-25

    This cleanup verification package documents completion of remedial action for the 118-C-1, 105-C Solid Waste Burial Ground. This waste site was the primary burial ground for general wastes from the operation of the 105-C Reactor and received process tubes, aluminum fuel spacers, control rods, reactor hardware, spent nuclear fuel and soft wastes.

  13. 78 FR 40738 - Proposed CERCLA Administrative Cost Recovery Settlement; Double H Pesticide Burial Site

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-08

    ... AGENCY Proposed CERCLA Administrative Cost Recovery Settlement; Double H Pesticide Burial Site AGENCY... incurred for the Double H Pesticide Burial Site in Grandview, Yakima County, Washington. Under this proposed settlement, the settling parties are Double H, L.P.; James T. Hansen; Linda L. Hansen; George...

  14. 32 CFR 553.17 - Persons ineligible for burial in an Army national cemetery.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Persons ineligible for burial in an Army national cemetery. 553.17 Section 553.17 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES ARMY NATIONAL CEMETERIES § 553.17 Persons ineligible for burial in an Army national cemetery....

  15. Effects of Urban Stream Burial on Organic Matter Dynamics and Reach Scale Nitrate Retention

    EPA Science Inventory

    Nitrogen (N) retention in streams is an important ecosystem service that may be affected by the widespread burial of streams in stormwater pipes in urban watersheds. We predicted that stream burial suppresses the capacity of streams to retain nitrate (NO3-) by eliminating primar...

  16. The formation of the patterns of desert shrub communities on the Western Ordos Plateau, China: the roles of seed dispersal and sand burial.

    PubMed

    Wang, Yange; Yang, Xiaohui; Shi, Zhongjie

    2013-01-01

    The western Ordos Plateau is a key area of shrub diversity and a National Nature Reserve of endangered shrub species in north-west China. Desert expansion is becoming the most important threat to these endangered species. However, little is known about the effects of sand burial on the dynamics of the shrub community. This study aims to investigate how the shrubs as a community and as different individual shrubs respond to the disturbances caused by the desert expansion. The approach used by this study is to separate the seed-dispersal strategy from the sand-burial forces that are involved in structuring the shrub communities at different disturbance stages. Four communities for different disturbance stages were surveyed by using 50×50 m plots. The individual shrubs were classified into coloniser and successor groups at the seed-dispersal stage and strong and weak sand-burial tolerance groups at the sand-expansion stage. We employed spatial point pattern analysis with null models for each community to examine the seed-dispersal strategy and sand-burial forces affecting community distribution patterns. At the seed-dispersal stage, the interactions between the colonisers and the successors showed significant positive correlation at a scale of 0-1 m and significant negative correlation at a scale of 2 m; significant negative correlations between the groups with strong and weak sand-burial tolerance in the early stage of sand expansion at scales of 3-6 m, and significant positive correlation in the later stage of sand expansion at a scale of 13 m, were found. Seed-dispersal strategy is a reasonable mechanism to explain the shrub community pattern formation in the earlier stages, whereas sand burial is the primary reason for the disappearance of shrubs with weak sand-burial tolerance, this irreversible disturbance causes homogenisation of the community structure and produces aging populations of shrub species. This has an important influence on the succession direction

  17. The Formation of the Patterns of Desert Shrub Communities on the Western Ordos Plateau, China: The Roles of Seed Dispersal and Sand Burial

    PubMed Central

    Wang, Yange; Yang, Xiaohui; Shi, Zhongjie

    2013-01-01

    The western Ordos Plateau is a key area of shrub diversity and a National Nature Reserve of endangered shrub species in north-west China. Desert expansion is becoming the most important threat to these endangered species. However, little is known about the effects of sand burial on the dynamics of the shrub community. This study aims to investigate how the shrubs as a community and as different individual shrubs respond to the disturbances caused by the desert expansion. The approach used by this study is to separate the seed-dispersal strategy from the sand-burial forces that are involved in structuring the shrub communities at different disturbance stages. Four communities for different disturbance stages were surveyed by using 50×50 m plots. The individual shrubs were classified into coloniser and successor groups at the seed-dispersal stage and strong and weak sand-burial tolerance groups at the sand-expansion stage. We employed spatial point pattern analysis with null models for each community to examine the seed-dispersal strategy and sand-burial forces affecting community distribution patterns. At the seed-dispersal stage, the interactions between the colonisers and the successors showed significant positive correlation at a scale of 0–1 m and significant negative correlation at a scale of 2 m; significant negative correlations between the groups with strong and weak sand-burial tolerance in the early stage of sand expansion at scales of 3–6 m, and significant positive correlation in the later stage of sand expansion at a scale of 13 m, were found. Seed-dispersal strategy is a reasonable mechanism to explain the shrub community pattern formation in the earlier stages, whereas sand burial is the primary reason for the disappearance of shrubs with weak sand-burial tolerance, this irreversible disturbance causes homogenisation of the community structure and produces aging populations of shrub species. This has an important influence on the succession

  18. Evidence supporting an intentional Neandertal burial at La Chapelle-aux-Saints

    PubMed Central

    Rendu, William; Beauval, Cédric; Crevecoeur, Isabelle; Bayle, Priscilla; Balzeau, Antoine; Bismuth, Thierry; Bourguignon, Laurence; Delfour, Géraldine; Faivre, Jean-Philippe; Lacrampe-Cuyaubère, François; Tavormina, Carlotta; Todisco, Dominique; Turq, Alain; Maureille, Bruno

    2014-01-01

    The bouffia Bonneval at La Chapelle-aux-Saints is well known for the discovery of the first secure Neandertal burial in the early 20th century. However, the intentionality of the burial remains an issue of some debate. Here, we present the results of a 12-y fieldwork project, along with a taphonomic analysis of the human remains, designed to assess the funerary context of the La Chapelle-aux-Saints Neandertal. We have established the anthropogenic nature of the burial pit and underlined the taphonomic evidence of a rapid burial of the body. These multiple lines of evidence support the hypothesis of an intentional burial. Finally, the discovery of skeletal elements belonging to the original La Chapelle aux Saints 1 individual, two additional young individuals, and a second adult in the bouffia Bonneval highlights a more complex site-formation history than previously proposed. PMID:24344286

  19. Analysis of the Effect of Time, Temperature, and Fuel Age on Helium Release from 238-Plutonium Dioxide Fuel

    NASA Astrophysics Data System (ADS)

    Barklay, Chadwick D.; Kramer, Daniel P.; Ruhkamp, Joseph D.

    2005-02-01

    The compound 238-plutonium dioxide has been employed over the last several decades as the fuel of choice in fabricating nuclear powered thermal to electrical converters. The alpha decay of 238-plutonium results in the generation of helium ions as a function of time. While the quantity of helium formed within the fuel can be easily calculated, its diffusion and/or release mechanism as a function of time, temperature, fuel quantity and age needs to be characterized. Within the scope of this paper the principle interest centers on determining the expected quantity of helium that will be released from solid 238-plutonium dioxide fuel forms enclosed within a primary containment vessel (PCV) under Hypothetical Accident Conditions (HAC) as described in 10 CFR 71.73(4). Once the quantity of helium released during HAC has been determined, the partial pressure increase due to the helium release can be calculated for a given shipping configuration. This partial pressure increase due to helium release during HAC for a selected shipping configuration can then be used to determine if the structural integrity of the package will be maintained or compromised during HAC. However, it is important to recognize that helium release is not a function of a particular shipping package, but as shall be demonstrated is a function of time, temperature, and fuel quantity and age.

  20. Analysis of the Effect of Time, Temperature, and Fuel Age on Helium Release from 238-Plutonium Dioxide Fuel

    SciTech Connect

    Barklay, Chadwick D.; Kramer, Daniel P.; Ruhkamp, Joseph D.

    2005-02-06

    The compound 238-plutonium dioxide has been employed over the last several decades as the fuel of choice in fabricating nuclear powered thermal to electrical converters. The alpha decay of 238-plutonium results in the generation of helium ions as a function of time. While the quantity of helium formed within the fuel can be easily calculated, its diffusion and/or release mechanism as a function of time, temperature, fuel quantity and age needs to be characterized. Within the scope of this paper the principle interest centers on determining the expected quantity of helium that will be released from solid 238-plutonium dioxide fuel forms enclosed within a primary containment vessel (PCV) under Hypothetical Accident Conditions (HAC) as described in 10 CFR 71.73(4). Once the quantity of helium released during HAC has been determined, the partial pressure increase due to the helium release can be calculated for a given shipping configuration. This partial pressure increase due to helium release during HAC for a selected shipping configuration can then be used to determine if the structural integrity of the package will be maintained or compromised during HAC. However, it is important to recognize that helium release is not a function of a particular shipping package, but as shall be demonstrated is a function of time, temperature, and fuel quantity and age.

  1. Stress-induced chemical waves in sediment burial diagenesis.

    PubMed

    Wang, Yifeng; Budd, David A

    2012-01-01

    Lateral metre-scale periodic variations in porosity and composition are found in many dolomite strata. Such variations may embed important information about dolomite formation and transformation. Here we show that these variations could be fossilized chemical waves emerging from stress-mediated mineral-water interaction during sediment burial diagenesis. Under the overlying loading, crystals in higher porosity domains are subjected to a higher effective stress, causing pressure solution. The dissolved species diffuse to and precipitate in neighbouring lower porosity domains, further reducing the porosity. This positive feedback leads to lateral porosity and compositional patterning in dolomite. The pattern geometry depends on fluid flow regimes. In a diffusion-dominated case, the low- and high-porosity domains alternate spatially with no directional preference, while, in the presence of an advective flow, this alternation occurs only along the flow direction, propagating like a chemical wave. Our work provides a new perspective for interpreting diagenetic signatures in sedimentary rocks. PMID:22353716

  2. Determination of post-burial interval using entomology: A review.

    PubMed

    Singh, Rajinder; Sharma, Sahil; Sharma, Arun

    2016-08-01

    Insects and other arthropods are used in different matters pertinent to the criminal justice system as they play very important role in the decomposition of cadavers. They are used as evidence in a criminal investigation to determine post mortem interval (PMI). Various researches and review articles are available on forensic entomology to determine PMI in the terrestrial environment but very less work has been reported in context to buried bodies. Burring the carcass, is one of the methods used by criminals to conceal the crime. So, to drive the attention of researchers toward this growing field and to help various investigating agencies, the present paper reviews the studies done on determination of post-burial interval (PBI), its importance and future prospective. PMID:27235895

  3. 77 FR 58591 - Report on Waste Burial Charges: Changes in Decommissioning Waste Disposal Costs at Low-Level...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-21

    ... Burial Facilities AGENCY: Nuclear Regulatory Commission. ACTION: Draft NUREG; request for comment... document entitled: NUREG-1307 Revision 15, ``Report on Waste Burial Charges: Changes in Decommissioning... a document is referenced. The NUREG-1307, Revision 15 is available electronically under...

  4. Effects of urban stream burial on nitrogen uptake and ecosystem metabolism: implications for watershed nitrogen and carbon fluxes

    EPA Science Inventory

    Urbanization has resulted in extensive burial and channelization of headwater streams, yet little is known about impacts on stream ecosystem functions critical for reducing downstream nitrogen pollution. To characterize the biogeochemical impact of stream burial, we measured NO3...

  5. Investigation and simulation on fate and transport of leachate from a livestock mortality burial site

    NASA Astrophysics Data System (ADS)

    Lim, J.-W.; Lee, S.; Kaown, D.; Lee, K.-K.

    2012-04-01

    Leachate released from livestock mortality burial during decomposition of carcasses can be a threat to groundwater quality. Monitoring study of groundwater quality in the vicinity of livestock burial reported that a caution is needed to prevent contamination of both groundwater and soil, especially in case of mortality burial (Glanville, 2000; Ritter and Chirnside, 1995). The average concentration of ammonium-N and chloride is reported to be 12,600 mg/l and 2,600 mg/l respectively, which is 2-4 times higher than leachate from earthen manure storages and landfills (Pratt, 2009). To assess the potential threat of burial leachate to groundwater quality, simulation of leachate transport is performed based on a hydrogeologic model of an actual mortality burial site. At the burial site of this study located at a hill slope, two mortality pits have been constructed along the slope to bury swine during the outbreak of nationwide foot and mouth disease(FMD) in 2011. Though the pits were partially lined with impermeable material, potential threat of leachate leakage is still in concern. Electrical resistivity survey has been performed several times at the burial site and abnormal resistivity zones have been detected which are supposed as leachate leakage from the burial. Subsurface model including unsaturated zone is built since the leakage is supposed to occur mainly in lateral of the burial pits which is in unsaturated zone. When examining leachate transport, main focus is given to a nitrogenous compound and colloidal character of FMD virus. Nitrifying of denitrifying characters of nitrogenous compound and transport of colloidal particles are affected mainly by soil water content in unsaturated zone. Thus, the fate and transport of burial leachate affected by seasonal variation in recharge pattern is investigated.

  6. Low-Temperature Aging Kinetics of a 15-Year Old Water-Quenched U-6wt.% Nb Alloy

    SciTech Connect

    Hsiung, L; Zhou, J

    2007-10-30

    It is well known that U-6wt.% Nb (U-14at.% Nb) alloy has a microstructure containing martensitic phases supersaturated with Nb that can be obtained by rapid quenching the alloy from {gamma} (bcc)-field solid solution to room temperature. The high cooling rate forces the {gamma}-phase solid solution to transform to variants of the low-temperature {alpha} (orthorhombic) phase in which Nb is forced to retain in the supersaturated solid solution. However, the crystal lattice of supersaturated solution formed by rapid quenching is in unstable conditions and is severely distorted since the solubility of Nb in the {alpha} phase at room temperature is nearly zero under an equilibrium condition. Two variant phases, a monoclinic distortion of {alpha} phase that is designated as {alpha}{double_prime} martensite and a tetragonal distortion of {gamma} phase that is designated as {gamma}{sup o} phase, can form in the as-quenched alloy, as shown in Fig. 1. We have learned from our previous TEM studies on the low-temperature aging of a water-quenched U6Nb (WQ-U6Nb) alloy that there are two possible transformation pathways for phase decomposition of the alloy supersaturated with 14 at.% of Nb upon aging at temperatures below 200 C, i.e., (1) supersaturated solid solution {alpha}{double_prime} {yields} spinodal decomposition {yields} {alpha}{sub 1} (Nb-lean) + {alpha}{sub 2} (Nb-rich) at 200 C and (2) supersaturated solid solution {alpha}{double_prime} {yields} spinodal ordering {yields}{alpha}{double_prime}{sub po} (partially ordered phase) {yields} phase decomposition and precipitation {yields} {alpha} (U) + {alpha}{sub o} (U{sub 3}Nb) at ambient temperatures [1]. The mechanisms for the spinodal transformation occurred at 200 C and the spinodal ordering occurred at ambient temperatures are quite similar; both are caused by the composition modulation of Nb except that the wavelength ({lambda} {approx} 3 nm) of modulation for spinodal decomposition is larger than that ({lambda

  7. Burial trench dynamic compaction demonstration at a humid site

    SciTech Connect

    Spalding, B.P.

    1985-01-01

    This task has the objective of determining the degree of consolidation which can be achieved by dynamic compaction of a closed burial trench within a cohesive soil formation. A seven-year-old burial trench in Solid Waste Storage Area (SWSA) 6 of Oak Ridge National Laboratory (ORNL) was selected for this demonstration. This 251 m/sup 3/ trench contained about 80 Ci of mixed radionuclides, mostly /sup 90/Sr, in 25 m/sup 3/ of waste consisting of contaminated equipment, dry solids, and demolition debris. Prior to compaction, a total trench void space of 79 m/sup 3/ was measured by pumping the trench full of water with corrections for seepage. Additional pre-compaction characterization included trench cap bulk density (1.68 kg/L), trench cap permeability (3 x 10/sup -7/ m/s), and subsurface waste/backfill hydraulic conductivity (>0.01 m/s). Compaction was achieved by repeatedly dropping a 4-ton steel-reinforced concrete cylinder from heights of 4 to 8 m using the whipline of a 70-ton crane. The average trench ground surface was depressed 0.79 m, with some sections over 2 m, yielding a surveyed volumetric depression which totaled to 64% of the measured trench void space. Trench cap (0 to 60 cm) bulk density and permeability were not affected by compaction indicating that the consolidation was largely subsurface. Neither surface nor airborne radioactive contamination were observed during repeated monitoring during the demonstration. Dynamic compaction was shown to be an excellent and inexpensive (i.e., about $20/m/sup 2/) method to collapse trench void space, thereby hastening subsidence and stabilizing the land surface. 15 refs., 10 figs., 3 tabs.

  8. CHALLENGES WITH RETRIEVING TRANSURANIC WASTE FROM THE HANFORD BURIAL GROUNDS

    SciTech Connect

    SWAN, R.J.; LAKES, M.E.

    2007-08-06

    The U.S. DOE's Hanford Reservation produced plutonium and other nuclear materials for the nation's defense starting in World War II. The defense mission generated wastes that were either retrievably stored (i.e. retrievably stored waste) and/or disposed of in burial grounds. Challenges have emerged from retrieving suspect TRU waste including adequacy of records, radiological concerns, container integrity, industrial hygiene and safety issues, the lack of processing/treatment facilities, and the integration of regulatory requirements. All retrievably stored waste is managed as mixed waste and assumed to be TRU waste, unless documented otherwise. Mixed waste is defined as radioactive waste that contains hazardous constituents. The Atomic Energy Act governs waste with radionuclides, and the Resource Conservation and Recovery Act (RCRA) governs waste with hazardous constituents. Waste may also be governed by the Toxic Substances Control Act (TSCA), and a portion may be managed under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). In 1970, TRU waste was required to be placed in 20-year retrievable storage and segregated from other Waste. Prior to that date, segregation did not occur. Because of the changing definition of TRU over the years, and the limitations of early assay equipment, all retrievably stored waste in the burial grounds is managed as suspect TRU. Experience has shown that some of this waste will be characterized as low-level (non-TRU) waste after assay. The majority of the retrieved waste is not amenable to sampling due to waste type and/or radiological issues. Key to waste retrieval and disposition are characterization, historical investigation and research, knowledge of past handling and packaging, as well as a broad understanding and application of the regulations.

  9. Recovery Strategy and Mechanism of Aged Lithium Ion Batteries after Shallow Depth of Discharge at Elevated Temperature.

    PubMed

    Cui, Yingzhi; Du, Chunyu; Gao, Yunzhi; Yang, Jie; Zhang, Lingling; Guan, Ting; Yang, Lijie; Cheng, Xinqun; Zuo, Pengjian; Ma, Yulin; Yin, Geping

    2016-03-01

    Performance degradation of prismatic lithium ion batteries (LIBs) with LiCoO2 and mesocarbon microbead as active materials is investigated at an elevated temperature for shallow depth of discharge. Aged LIBs are disassembled to characterize the interface morphology, bulk structure, and reversible capacity of an individual electrode. It is found that the formation of interfacial blocking layer (IBL) on the anode results in the cathode state of charge (SOC) offset, which is the primary reason for the cathode degradation. The main capacity degradation of the anode is attributed to the IBL on the anode surface that impedes the intercalation and deintercalation of lithium ions. Because the full battery capacity is limited by the cathode during aging, the cathode SOC offset is the most important reason for the full battery capacity loss. Interestingly, the capacity of aged LIBs can be recovered to a relative high level after adding the electrolyte, rather than the solvent. This recovery is attributed to the relief of the cathode SOC offset and the dissolution of the anode IBL, which reopens the intercalation and deintercalation paths of lithium ions on the anode. Moreover, it is revealed that the relief of cathode SOC offset and the dissolution of anode IBL trigger and promote mutually to drive the recovery of LIBs. PMID:26848629

  10. Burial and exhumation history of the Polish Outer Carpathians: Discriminating the role of thrusting and post-thrusting extension

    NASA Astrophysics Data System (ADS)

    Andreucci, B.; Castelluccio, A.; Jankowski, L.; Mazzoli, S.; Szaniawski, R.; Zattin, M.

    2013-11-01

    Several tectonic processes have been proposed to be important in the Alpine to the recent evolution of the Polish Outer Carpathians, i.e., Paleogene-Neogene thrusting, post-thrusting extension, Quaternary reactivation of compression. This work tests the effect of these processes on exhumation of the wedge, in order to verify their timing and relative role in shaping the Polish Outer Carpathians. AFT, AHe and ZHe analyses were performed on samples collected along the study region. This allowed the reconstruction of their post-depositional minimum heating, depth of burial and timing of cooling and exhumation. After deposition samples from the innermost units were heated up to temperatures of ca. 60-120 °C (ca. 4-9 km), whereas samples from the outer units were heated to temperatures lower than 60 °C (ca. 4 km). Cooling and exhumation occurred progressively later from west to east (between ca. 25 and 10 Ma in the western sector, between ca. 15 and 5 Ma in the eastern sector). These results have been put in relationship with single structural features to understand the relative role of thrusts and normal faults. In the eastern sector of the study region samples at the footwall of significant normal faults show a higher degree of reset and younger ages than samples located at the hangingwall. This implies that, in this sector, extensional tectonics played an important role in exhumation. However, proper tectonic exhumation only had a minor role, the major exhumation mechanism being erosion, which is enhanced in the footwalls and reduced in the hangingwalls. In the western sector of the Polish Outer Carpathians only in few cases evidence of enhanced erosion to the footwall of major normal faults could be observed based on the present data. In this region the wedge exhumed mainly as a response to thrusting and normal faulting only played a minor role, locally modifying the pattern of erosion. Finally no major exhumation events occurred after Miocene, pointing to a minor

  11. The effects of solution treatment on the mechanical properties of age-hardened A-286 bar stock at elevated and cryogenic temperature

    NASA Technical Reports Server (NTRS)

    Montano, J. W.

    1972-01-01

    The mechanical properties are presented of solution treated and age hardened A-286 corrosion resistant steel bar stock. Material solution treated at 899 C or 982 C, each followed by an age hardening treatment of 718 C, was evaluated. Test specimens manufactured from 1.50 inch (3.81 cm) diameter bar stock were tested at temperatures from +649 C to -253 C. The test data indicated excellent tensile, yield, elongation and reduction-in-area properties at all testing temperatures for both solution treated and aged materials. Cryogenic temperature notched tensile, impact, and shear tests indicated excellent notch strength, ductility, and shear values. There was very little difference in the mechanical properties of the two solution treated and aged materials. The only exception was that the 962 C solution treated and aged material had superior stress rupture properties at 649 C.

  12. Colloid-associated plutonium aged at room temperature: evaluating its transport velocity in saturated coarse-grained granites.

    PubMed

    Xie, Jinchuan; Lin, Jianfeng; Wang, Yu; Li, Mei; Zhang, Jihong; Zhou, Xiaohua; He, Yifeng

    2015-01-01

    The fate and transport of colloidal contaminants in natural media are complicated by physicochemical properties of the contaminants and heterogeneous characteristics of the media. Size and charge exclusion are two key microscopic mechanisms dominating macroscopic transport velocities. Faster velocities of colloid-associated actinides than that of (3)H2O were consistently indicated in many studies. However, dissociation/dissolution of these sorbed actinides (e.g., Pu and Np), caused by their redox reactions on mineral surfaces, possibly occurred under certain chemical conditions. How this dissolution is related to transport velocities remains unanswered. In this study, aging of the colloid-associated Pu (pseudo-colloid) at room temperature and transport through the saturated coarse-grained granites were performed to study whether Pu could exhibit slower velocity than that of (3)H2O (UPu/UT <1). The results show that oxidative dissolution of Pu(IV) associated with the surfaces of colloidal granite particles took place during the aging period. The relative velocity of UPu/UT declined from 1.06 (unaged) to 0.745 (135 d) over time. Size exclusion limited to the uncharged nano-sized particles could not explain such observed UPu/UT <1. Therefore, the decline in UPu/UT was ascribed to the presence of electrostatic attraction between the negatively charged wall of granite pore channels and the Pu(V)O2(+), as evidenced by increasing Pu(V)O2(+) concentrations in the suspensions aged in sealed vessels. As a result of this attraction, Pu(V)O2(+) was excluded from the domain closer to the centerline of pore channels. This reveals that charge exclusion played a more important role in dominating UPu than the size exclusion under the specific conditions, where oxidative dissolution of colloid-associated Pu(IV) was observed in the aged suspensions. PMID:25462640

  13. Colloid-associated plutonium aged at room temperature: evaluating its transport velocity in saturated coarse-grained granites

    NASA Astrophysics Data System (ADS)

    Xie, Jinchuan; Lin, Jianfeng; Wang, Yu; Li, Mei; Zhang, Jihong; Zhou, Xiaohua; He, Yifeng

    2015-01-01

    The fate and transport of colloidal contaminants in natural media are complicated by physicochemical properties of the contaminants and heterogeneous characteristics of the media. Size and charge exclusion are two key microscopic mechanisms dominating macroscopic transport velocities. Faster velocities of colloid-associated actinides than that of 3H2O were consistently indicated in many studies. However, dissociation/dissolution of these sorbed actinides (e.g., Pu and Np), caused by their redox reactions on mineral surfaces, possibly occurred under certain chemical conditions. How this dissolution is related to transport velocities remains unanswered. In this study, aging of the colloid-associated Pu (pseudo-colloid) at room temperature and transport through the saturated coarse-grained granites were performed to study whether Pu could exhibit slower velocity than that of 3H2O (UPu/UT < 1). The results show that oxidative dissolution of Pu(IV) associated with the surfaces of colloidal granite particles took place during the aging period. The relative velocity of UPu/UT declined from 1.06 (unaged) to 0.745 (135 d) over time. Size exclusion limited to the uncharged nano-sized particles could not explain such observed UPu/UT < 1. Therefore, the decline in UPu/UT was ascribed to the presence of electrostatic attraction between the negatively charged wall of granite pore channels and the Pu(V)O2+, as evidenced by increasing Pu(V)O2+ concentrations in the suspensions aged in sealed vessels. As a result of this attraction, Pu(V)O2+ was excluded from the domain closer to the centerline of pore channels. This reveals that charge exclusion played a more important role in dominating UPu than the size exclusion under the specific conditions, where oxidative dissolution of colloid-associated Pu(IV) was observed in the aged suspensions.

  14. Neonatal stress affects the aging trajectory of female rats on the endocrine, temperature, and ventilatory responses to hypoxia.

    PubMed

    Fournier, Sébastien; Gulemetova, Roumiana; Baldy, Cécile; Joseph, Vincent; Kinkead, Richard

    2015-04-01

    Human and animal studies on sleep-disordered breathing and respiratory regulation show that the effects of sex hormones are heterogeneous. Because neonatal stress results in sex-specific disruption of the respiratory control in adult rats, we postulate that it might affect respiratory control modulation induced by ovarian steroids in female rats. The hypoxic ventilatory response (HVR) of adult female rats exposed to neonatal maternal separation (NMS) is ∼30% smaller than controls (24), but consequences of NMS on respiratory control in aging female rats are unknown. To address this issue, whole body plethysmography was used to evaluate the impact of NMS on the HVR (12% O2, 20 min) of middle-aged (MA; ∼57 wk old) female rats. Pups subjected to NMS were placed in an incubator 3 h/day for 10 consecutive days (P3 to P12). Controls were undisturbed. To determine whether the effects were related to sexual hormone decline or aging per se, experiments were repeated on bilaterally ovariectomized (OVX) young (∼12 wk old) adult female rats. OVX and MA both reduced the HVR significantly in control rats but had little effect on the HVR of NMS females. OVX (but not aging) reduced the anapyrexic response in both control and NMS animals. These results show that hormonal decline decreases the HVR of control animals, while leaving that of NMS female animals unaffected. This suggests that neonatal stress alters the interaction between sex hormone regulation and the development of body temperature, hormonal, and ventilatory responses to hypoxia. PMID:25652536

  15. 38 CFR 1.10 - Eligibility for and disposition of the United States flag for burial purposes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... disposition of the United States flag for burial purposes. 1.10 Section 1.10 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS GENERAL PROVISIONS The United States Flag for Burial Purposes § 1.10 Eligibility for and disposition of the United States flag for burial purposes. (a) Eligibility...

  16. 38 CFR 1.10 - Eligibility for and disposition of the United States flag for burial purposes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... disposition of the United States flag for burial purposes. 1.10 Section 1.10 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS GENERAL PROVISIONS The United States Flag for Burial Purposes § 1.10 Eligibility for and disposition of the United States flag for burial purposes. (a) Eligibility...

  17. 38 CFR 1.10 - Eligibility for and disposition of the United States flag for burial purposes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... disposition of the United States flag for burial purposes. 1.10 Section 1.10 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS GENERAL PROVISIONS The United States Flag for Burial Purposes § 1.10 Eligibility for and disposition of the United States flag for burial purposes. (a) Eligibility...

  18. 38 CFR 1.10 - Eligibility for and disposition of the United States flag for burial purposes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... disposition of the United States flag for burial purposes. 1.10 Section 1.10 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS GENERAL PROVISIONS The United States Flag for Burial Purposes § 1.10 Eligibility for and disposition of the United States flag for burial purposes. (a) Eligibility...

  19. 31 CFR 538.535 - Importation and exportation of human remains for burial, cremation, or interment authorized.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... remains for burial, cremation, or interment authorized. 538.535 Section 538.535 Money and Finance... Policy § 538.535 Importation and exportation of human remains for burial, cremation, or interment authorized. (a) The importation into the United States of human remains for burial, cremation, or...

  20. 31 CFR 538.535 - Importation and exportation of human remains for burial, cremation, or interment authorized.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... remains for burial, cremation, or interment authorized. 538.535 Section 538.535 Money and Finance... Policy § 538.535 Importation and exportation of human remains for burial, cremation, or interment authorized. (a) The importation into the United States of human remains for burial, cremation, or...

  1. 31 CFR 538.535 - Importation and exportation of human remains for burial, cremation, or interment authorized.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... remains for burial, cremation, or interment authorized. 538.535 Section 538.535 Money and Finance... Policy § 538.535 Importation and exportation of human remains for burial, cremation, or interment authorized. (a) The importation into the United States of human remains for burial, cremation, or...

  2. Effects of breeder age, broiler strain, and eggshell temperature on development and physiological status of embryos and hatchlings.

    PubMed

    Nangsuay, A; Meijerhof, R; van den Anker, I; Heetkamp, M J W; Morita, V De Souza; Kemp, B; van den Brand, H

    2016-07-01

    Breeder age and broiler strain can influence the availability of nutrients and oxygen, particularly through differences in yolk size and shell conductance. We hypothesized that these egg characteristics might affect embryonic responses to changes in eggshell temperature (EST). This study aimed to investigate the effect of breeder age, broiler strain, and EST on development and physiological status of embryos. A study was designed as a 2 × 2 × 2 factorial arrangement using 4 batches of 1,116 hatching eggs of 2 flock ages at 29 to 30 wk (young) and 54 to 55 wk (old) of Ross 308 and Cobb 500. EST of 37.8 (normal) or 38.9°C (high) was applied from incubation d 7 (E7) until hatching. The results showed that breeder age rather than broiler strain had an influence on yolk size (P = 0.043). The shell conductance was higher in Ross 308 than in Cobb 500 (P < 0.001). A high EST resulted in a higher yolk free body mass (YFBM) compared to the normal EST at E14 and E16, but at 3 h after hatch YFBM was lower when eggs were incubated at high EST compared to normal EST (all P < 0.001). Cobb 500 eggs yielded embryos with a lower YFBM at E14, E18, and 3 h after hatch (all P < 0.05) than Ross 308 eggs. Breeder age had no effect on YFBM, but the RSY weight was higher in embryos from the old flock compared to the young flock embryos at E14 and E16 (both P < 0.05). A 3-way interaction among breeder age, strain, and EST was found, especially for incubation duration, navel quality, and relative heart and stomach weights at 3 h after hatch (all P < 0.05). Based on the results obtained, we conclude that oxygen availability rather than nutrient availability determines embryonic development, and the egg characteristics affected embryonic responses to changes of EST, especially for variables related to chick quality. PMID:26957632

  3. Effect of high-temperature aging on electrical properties of HipercoxAE 27, HipercoxAE 50, and HipercoxAE 50 HS alloys

    NASA Astrophysics Data System (ADS)

    Geist, B.; Peterson, T.; Horwath, J. C.; Turgut, Z.; Huang, M. Q.; Snyder, R. A.; Fingers, R. T.

    2003-05-01

    Some more electric aircraft concepts require soft magnetic FeCo materials to be stable at temperatures as high as 773 K for long periods of time. At this high operating temperature, aging related processes may occur that result in changes in material properties. The material supplier typically specifies only room-temperature properties, and only limited reports are available on properties at elevated temperatures. The change in properties as a function of time at 773 K will give information on the lifetime of the material to assist designers when selecting materials for high-temperature applications. We have conducted a study on the effects of long-term aging on the magnetic, mechanical, and electrical properties of Hiperco® 27, Hiperco® 50, and Hiperco® 50 HS FeCo soft magnetic alloys. Samples of each material were aged in argon for 100, 1000, 2000, and 5000 h at 773 K. Here, we report the changes in electrical resistivity after aging. Of the three alloys, high-temperature aging has the greatest effect on the resistivity of Hiperco® 50. The electrical resistivities for each sample are compared and conclusions are drawn on the relative thermal stability of each alloy. The changes in electrical resistivities for each alloy are also related to changes in other properties, such as total power loss and coercivity, that were observed during this study on aging.

  4. Sorption Characteristic of Phenanthrene on Biochar-Amended Soils: Effect of feedstock, pyrolysis temperature, and aging duration

    NASA Astrophysics Data System (ADS)

    Hyun, S.; Kim, C.; Kim, Y. S.; Kim, J.

    2015-12-01

    The high sorption capacity of biochar is widely known in environmental studies. Especially, biochar is effective for removal of hydrophobic organic compounds (HOCs) due to high surface area and porosity. In this study, the sorption characteristic of biochar-amended soil was evaluated by sorption kinetic experiment of phenanthrene (PHE). For PHE sorption test, the effect of biochar feedstock (sludge waste char (SWC), municipal waste char (MWC) and wood char (WC), Giant Miscanthus (GM)), pyrolysis temperature (400°C, 500°C and 700°C,), and duration of amending period (0, 3, 6, and 12 months) was assessed. Field Emission-Scanning Electron Microscopy (FE-SEM) and Fourier Transform-Infrared Spectroscopy (FT-IR) techniques were used to detect pore structure and the surface functional group of biochar amended soils. For all kinetic tests, apparent sorption equilibrium was attained in 24 hr. The result showed that sorption capacity of biochar amended soils was greatly influenced by biochar feedstock and pyrolysis temperature. For all samples, the sorption capacity of PHE by biochar amended soils decreased with aging period. This observation is due to the fact that the aromatic characters of biochar are different by feedstock and pyrolysis temperature and the amount of O-containing hydrophilic functional groups increased surfaces of biochar by natural oxidation (e.g. carboxyl groups) as confirmed by the result of FT-IR and FE-SEM. In addition, biochar pore blockage by inorganic minerals, which tended to increase with aging period, might attenuate the sorption capacity of samples. In conclusion, biochar derived from various feed stocks are all effective for PHE sorption. But the sorption capacity of biochar amended soils decreased with increasing aging duration most likely due to increasing hydrophilic functional groups of biochar surfaces and pore blockage by inorganic minerals in the weathering processes. Therefore, for the design of biochar amendment to attenuate

  5. High-precision abundances of elements in solar twin stars. Trends with stellar age and elemental condensation temperature

    NASA Astrophysics Data System (ADS)

    Nissen, P. E.

    2015-07-01

    Context. High-precision determinations of abundances of elements in the atmospheres of the Sun and solar twin stars indicate that the Sun has an unusually low ratio between refractory and volatile elements. This has led to the suggestion that the relation between abundance ratios, [X/Fe], and elemental condensation temperature, TC, can be used as a signature of the existence of terrestrial planets around a star. Aims: HARPS spectra with S/N ≳ 600 for 21 solar twin stars in the solar neighborhood and the Sun (observed via reflected light from asteroids) are used to determine very precise (σ ~ 0.01 dex) differential abundances of elements in order to see how well [X/Fe] is correlated with TC and other parameters such as stellar age. Methods: Abundances of C, O, Na, Mg, Al, Si, S, Ca, Ti, Cr, Fe, Ni, Zn, and Y are derived from equivalent widths of weak and medium-strong spectral lines using MARCS model atmospheres with parameters determined from the excitation and ionization balance of Fe lines. Non-LTE effects are considered and taken into account for some of the elements. In addition, precise (σ ≲ 0.8 Gyr) stellar ages are obtained by interpolating between Yonsei-Yale isochrones in the log g - Teff diagram. Results: It is confirmed that the ratio between refractory and volatile elements is lower in the Sun than in most of the solar twins (only one star has the same [X/Fe]-TC distribution as the Sun), but for many stars, the relation between [X/Fe] and TC is not well defined. For several elements there is an astonishingly tight correlation between [X/Fe] and stellar age with amplitudes up to ~0.20 dex over an age interval of eight Gyr in contrast to the lack of correlation between [Fe/H] and age. While [Mg/Fe] increases with age, the s-process element yttrium shows the opposite behavior meaning that [Y/Mg] can be used as a sensitive chronometer for Galactic evolution. The Na/Fe and Ni/Fe ratios are not well correlated with stellar age, but define a tight Ni

  6. Geology and hydrology of radioactive solid-waste burial grounds at the Hanford Reservation, Washington

    USGS Publications Warehouse

    LaSala, Albert Mario; Doty, Gene C.

    1976-01-01

    The geology and hydrology of radioactive solid waste burial grounds at the Hanford Reservation were investigated, using existing data, by the U.S. Geological Survey as part of the waste management plan of the Richland Operations Office of the Energy Research and Development Administration. The purpose of the investigation was to assist the operations office in characterizing the burial sites as to present environmental safety and as to their suitability for long-term storage (several thousand to tens of thousands of years) of radioactive sol id wastes. The burial ground sites fall into two classifications: (1) those on the low stream terraces adjacent to the Columbia River, mainly in the 100 Areas and 300 Area, and (2) those lying on the high terraces south of Gable Mountain in the 200 Areas. Evaluation of the suitability of the burial grounds for long-term storage was made almost entirely on hydrologic, geologic, and topographic criteria. Of greatest concern was the possibility that radionuclides might be leached from the buried wastes by infiltrating water and carried downward to the water table. The climate is semi-arid and the average annual precipitation is 6.4 inches at the Hanford Meteorological Station. However, the precipitation is seasonally distributed with about 50 percent occurring during the months of November, December, January, and February when evapotranspiration is negligible and conditions for infiltration are most favorable. None of the burial grounds are instrumented with monitoring devices that could be used to determine if radionuclides derived from them are reaching the water table. Burial grounds on the low stream terraces are mainly underlain by permeable materials and the water table lies at relatively shallow depths. Radionuclides conceivably could be leached from these burial grounds by percolating soil water, and radionuclides might reach the Columbia River in a relatively short time. These sites could also be inundated by erosion

  7. Organic Carbon Burial in Lakes and Reservoirs of the Conterminous United States.

    PubMed

    Clow, David W; Stackpoole, Sarah M; Verdin, Kristine L; Butman, David E; Zhu, Zhiliang; Krabbenhoft, David P; Striegl, Robert G

    2015-07-01

    Organic carbon (OC) burial in lacustrine sediments represents an important sink in the global carbon cycle; however, large-scale OC burial rates are poorly constrained, primarily because of the sparseness of available data sets. Here we present an analysis of OC burial rates in water bodies of the conterminous U.S. (CONUS) that takes advantage of recently developed national-scale data sets on reservoir sedimentation rates, sediment OC concentrations, lake OC burial rates, and water body distributions. We relate these data to basin characteristics and land use in a geostatistical analysis to develop an empirical model of OC burial in water bodies of the CONUS. Our results indicate that CONUS water bodies sequester 20.8 (95% CI: 9.4-65.8) Tg C yr(-1), and spatial patterns in OC burial are strongly influenced by water body type, size, and abundance; land use; and soil and vegetation characteristics in surrounding areas. Carbon burial is greatest in the central and southeastern regions of the CONUS, where cultivation and an abundance of small water bodies enhance accumulation of sediment and OC in aquatic environments. PMID:26061185

  8. Accelerated step-temperature aging of Al/x/Ga/1-x/As heterojunction laser diodes

    NASA Technical Reports Server (NTRS)

    Kressel, H.; Ettenberg, M.; Ladany, I.

    1978-01-01

    Double-heterojunction A2(0.3)Ga(0.7)As/Al(0.08)Ga(0.92)As lasers (oxide-striped and Al2O3 facet coated) were subjected to step-temperature aging from 60 to 100 C. The change in threshold current and spontaneous output was monitored at 22 C. The average time required for a 20% pulsed threshold current increase ranges from about 500 h, when operating at 100 C, to about 5000 h at a 70 C ambience. At 22 C, the extrapolated time is about 1 million h. The time needed for a 50% spontaneous emission reduction is of the same order of magnitude. The resulting activation energies are approximately 0.95 eV for laser degradation and approximately 1.1 eV for the spontaneous output decrease

  9. Influence of temperature on carbon and nitrogen dynamics during in situ aeration of aged waste in simulated landfill bioreactors.

    PubMed

    Tong, Huanhuan; Yin, Ke; Giannis, Apostolos; Ge, Liya; Wang, Jing-Yuan

    2015-09-01

    The effect of temperature on carbon and nitrogen compounds during in situ aeration of aged waste was investigated in lab-scale simulated landfill bioreactors at 35, 45 and 55 °C, respectively. The bioreactor operated at 55 °C presented the highest carbon mineralization rate in the initial stage, suggesting accelerated biodegradation rates under thermophilic conditions. The nitrogen speciation study indicated that organic nitrogen was the dominant species of total N in aerobic bioreactors due to ammonia removal. Leachate organic nitrogen was further fractionated to elucidate the fate of individual constituent. Detailed investigation revealed the higher bioconversion rates of N-humic and N-fulvic compounds compared to hydrophilic compounds in thermophilic conditions. At the end, waste material in 55 °C bioreactor was richer in highly matured humic substances (HS) verifying the high bioconversion rates. PMID:26026292

  10. On problem of burial of solid tritium-containing high radioactive wastes

    SciTech Connect

    Voitenko, V.A.; Kolomiets, N.F.

    1993-12-31

    Within the range of realization of national programs of treatment with radioactive wastes the problems of localization and burial of solid tritium-containing wastes is of great importance. This problem is characterized by a number of peculiarities connected with the localization of tritium-containing wastes on one side and on the other hand, it requires the specific approach connected with the diversity of ways of tritium migration into the environment with its genetic significant, and as a rule, with extremely high waste activity. As a metal-sorbent in given products, titanium is used in a form of thin films sprayed on various metal backings. Mainly, the corrosion-resistant materials are chosen for backing materials such as, molybdenum, copper or stainless steel, made in a form of discs or rectangle plates with thickness from 0.1 to 2 mm and area of 20 cm{sup 2}. The activity of one article may be attained to 100 Ci. Tritium is well sorbed by titanium at the temperature approximately 400 C (its solubility reaches 467 cm per 1 g of titanium) and is relatively well kept by it up to this temperature.

  11. Epigenetic dolomitization of the Přaídolí formation (Upper Silurian), the Barrandian basin, Czech Republic: implications for burial history of Lower Paleozoic strata

    NASA Astrophysics Data System (ADS)

    Suchý, V.; Rozkošný, I.; Žák, K.; Franců, J.

    1996-06-01

    Stratabound epigenetic dolomite occurs in carbonate facies of the Barrandian basin (Silurian and Devonian), Czech Republic. The most intense dolomitization is developed in bioclastic calcarenites within the transition between micritic limestone and shaledominated Přídolí and Lochkov formations deposited on a carbonate slope. Medium-crystalline (100-400 µm), inclusion-rich, xenotopic matrix dolomite ( δ 18O=-4.64 to -3.40‰ PDB; δ 13C=+1.05 to +1.85‰ PDB) which selectively replaced most of the bioclastic precursor is volumetrically the most important dolomite type. Coarse crystalline saddle dolomite ( δ 18O=-8.04 to -5.14‰ PDB; δ 18C=+0.49 to +1.49 PDB) which precipitated in fractures and vugs within the matrix dolomite represents a later diagenetic dolomitization event. In some vugs, saddle dolomite coprecipitated with petroleum inclusion-rich authigenic quartz crystals and minor sulfides which, in turn, were post-dated by semisolid asphaltic bitumen. The interpretation of the dolomitization remains equivocal. Massive xenotopic dolomite, although generally characteristic of a deeper burial setting, may have been formed by a recrystallization of an earlier, possibly shallow burial dolomite. Deeper burial recrystallization by reactive basinal pore fluids that presumably migrated through the more permeable upper portion of the Přídolí sequence appears as a viable explanation for this dolomitization overprint. Saddle dolomite cement of the matrix dolomite is interpreted as the last dolomitization event that occurred during deep burial at the depth of the oil window zone. The presence of saddle dolomite, the fluid inclusion composition of associated quartz crystals, and vitrinite paleogeothermometry of adjacent sediments imply diagenetic burial temperatures as high as 160°C. Although high geothermal gradients in the past or the involvement of hydrothermally influenced basinal fluids can account for these elevated temperatures, burial heating beneath

  12. Epigenetic dolomitization of the Přídolí formation (Upper Silurian), the Barrandian basin, Czech Republic: implications for burial history of Lower Paleozoic strata

    NASA Astrophysics Data System (ADS)

    Suchý, V.; Rozkošný, I.; Žák, K.; Franců, J.

    Stratabound epigenetic dolomite occurs in carbonate facies of the Barrandian basin (Silurian and Devonian), Czech Republic. The most intense dolomitization is developed in bioclastic calcarenites within the transition between micritic limestone and shale-dominated Přídolí and Lochkov formations deposited on a carbonate slope. Medium-crystalline (100-400μm), inclusion-rich, xenotopic matrix dolomite (δ18O=-4.64 to -3.40ö PDBδ13C=+1.05 to +1.85ö PDB) which selectively replaced most of the bioclastic precursor is volumetrically the most important dolomite type. Coarse crystalline saddle dolomite (δ18O=-8.04 to -5.14ö PDBδ18C=+0.49 to +1.49 PDB) which precipitated in fractures and vugs within the matrix dolomite represents a later diagenetic dolomitization event. In some vugs, saddle dolomite coprecipitated with petroleum inclusion-rich authigenic quartz crystals and minor sulfides which, in turn, were postdated by semisolid asphaltic bitumen. The interpretation of the dolomitization remains equivocal. Massive xenotopic dolomite, although generally characteristic of a deeper burial setting, may have been formed by a recrystallization of an earlier, possibly shallow burial dolomite. Deeper burial recrystallization by reactive basinal pore fluids that presumably migrated through the more permeable upper portion of the Přídolí sequence appears as a viable explanation for this dolomitization overprint. Saddle dolomite cement of the matrix dolomite is interpreted as the last dolomitization event that occurred during deep burial at the depth of the oil window zone. The presence of saddle dolomite, the fluid inclusion composition of associated quartz crystals, and vitrinite paleogeothermometry of adjacent sediments imply diagenetic burial temperatures as high as 160 °C. Although high geothermal gradients in the past or the involvement of hydrothermally influenced basinal fluids can account for these elevated temperatures, burial heating beneath approximately 3

  13. Hydrologic and micrometeorologic data from an unsaturated zone study at a low-level radioactive waste burial site near Barnwell, South Carolina

    USGS Publications Warehouse

    Dennehy, K.F.; McMahon, P.B.

    1985-01-01

    Two years of selected hydrologic and micrometeorologic data collected at a low-level radioactive waste burial site near Barnwell, South Carolina are available on magnetic tape in card-image format. Hydrologic data include daily measurements of soil-moisture tension, soil-moisture specific conductance, and soil temperature at four monitoring site locations. Micrometeorlogic data include hourly measurements for the following parameters: dry- and wet-bulb temperatures, soil temperatures, soil heat flux, wind speeds and direction, incoming and reflected short-wave solar radiation, incoming and emitted long-wave radiation, net radiation and precipitation. (USGS)

  14. Age and thinning effects on the temperature sensitivities of respiration in loblolly pine plantations in eastern North Carolina

    NASA Astrophysics Data System (ADS)

    Miao, G.; Noormets, A.

    2014-12-01

    Age and silvicultural interventions are two important factors to characterize the development of commercial plantations. Effects of the two factors are of importance in quantifying the carbon dynamics in these artificial systems, but remain unclear. From 9 years (2005-2013) of carbon exchange observations in a mature (13 years old in 2005) and a young (2 years old in 2005) loblolly pine plantations located on the lower coastal plain in eastern North Carolina, we investigated the difference in temperature sensitivities (Q10) of ecosystem respiration (ER) of the two plantations of different ages. The mature plantation was thinned in August 2009, therefore, we compared the ER before and after thinning to estimate the potential response of Q10 to thinning in the mature plantation. Before thinning (years of 2005 - early half year of 2009), Q10 of ER in the mature plantation was similar across years. Even during a severe drought (e.g. 2007), Q10 did not differ from other years (p = 0.2 - 0.8 between years). The mean Q10 before harvesting was 2.33±0.05 (mean±SE). After thinning (years of 2010-2013), there was significant inter-annual variation in Q10 with an overall estimate at 2.23±0.05. The young plantation also exhibited significant inter-annual variations in Q10, and the overall Q10 was 2.99±0.11, higher than that of the mature plantation. The increased variability of temperature sensitivity after thinning in the mature plantation might be associated with the altered physical environment by thinning such as soil bulk density and soil water content, whereas the similar pattern in the young plantation might result from the primary contribution of heterotrophic respiration and also be confounded with the fast growth of young seedlings.

  15. Technology, Safety and Costs of Decommissioning a Reference Low-Level Waste Burial Ground. Appendices

    SciTech Connect

    1980-06-01

    Safety and cost information are developed for the conceptual decommissioning of commercial low-level waste (LLW) burial grounds. Two generic burial grounds, one located on an arid western site and the other located on a humid eastern site, are used as reference facilities for the study. The two burial grounds are assumed to have the same site capacity for waste, the same radioactive waste inventory, and similar trench characteristics and operating procedures. The climate, geology. and hydrology of the two sites are chosen to be typical of real western and eastern sites. Volume 2 (Appendices) contains the detailed analyses and data needed to support the results given in Volume 1.

  16. Hydrogeological influences on radionuclide migration from the major radioactive waste burial sites at Chernobyl (A review)

    SciTech Connect

    Dgepo, S.P.; Skalsky, A.S.; Bugai, D.A.; Marchuk, V.V.; Waters, R.D.

    1994-03-01

    This paper summarizes the recent hydrogeological investigations of several research organizations on waste confinement at the major radioactive waste (RW) burial sites immediately adjacent to the Chernobyl Nuclear Power Plant (Ch. NPP). Hydrogeological conditions and radiologic ground-water contamination levels are described. Ongoing ground-water monitoring practices are evaluated. The chemical and physical characteristics of the radionuclides within the burial sites are considered. Ground water and radionuclide transport modeling studies related to problems of the RW disposal sites are also reviewed. Current concerns on future impacts of the RW burial sites on the hydrological environment and water resources of the Ch.NPP area are discussed.

  17. Technology, Safety and Costs of Decommissioning a Reference Low-Level Waste Burial Ground. Main Report

    SciTech Connect

    Murphy, E. S.; Holter, G. M.

    1980-06-01

    Safety and cost information are developed for the conceptual decommissioning of commercial low-level waste (LLW) burial grounds. Two generic burial grounds, one located on an arid western site and the other located on a humid eastern site, are used as reference facilities for the study. The two burial grounds are assumed to have the same site capacity for waste, the same radioactive waste inventory, and similar trench characteristics and operating procedures. The climate, geology. and hydrology of the two sites are chosen to be typical of real western and eastern sites. Volume 1 (Main Report) contains background information and study results in summary form.

  18. Earliest evidence of personal ornaments associated with burial: the Conus shells from Border Cave.

    PubMed

    d'Errico, Francesco; Backwell, Lucinda

    2016-04-01

    The four to six month old infant from Border Cave, found with a perforated Conus shell in a pit excavated in Howiesons Poort (HP) layers dated to 74 ± 4 BP, is considered the oldest instance of modern human burial from Africa, and the earliest example of a deceased human interred with a personal ornament. In this article we present new data retrieved from unpublished archives on the burial excavation, and conduct an in-depth analysis of the Conus found with the infant, and a second similar Conus that probably originates from the same layer. Based on morphological, morphometric and ecological evidence we assign these two shells to Conus ebraeus Linnaeus 1758, a tropical species still living on the nearest coastline to Border Cave, in northern KwaZulu-Natal. This attribution changes the paleoclimatic setting inferred from the previous ascription of these shells to Conus bairstowi, a species endemic to the Eastern Cape and adapted to colder sea surface temperatures. Reconstructions of 74 ka sea surface temperatures along the southern African east coast are consistent with our reassignment. Analysis of shell thanatocoenoses and biocoenosis from the KwaZulu-Natal coast, including microscopic study of their surfaces, reveals that complete, well preserved living or dead Conus, such as those found at Border Cave, are rare on beaches, can be collected at low tide at a depth of c. 0.5-2 m among the rocks, and that the archeological shells were dead when collected. We demonstrate that the perforations at the apex were produced by humans, and that traces of wear due to prolonged utilization as an ornament are present. SEM-EDX analysis of patches of red residue on the Conus found in the pit with the infant indicates that it is composed of iron, phosphorus, silicon, aluminium, and magnesium. Results indicate that, at least in some areas of southern Africa, the use of marine gastropods as ornaments, already attested in Still Bay, extended to the first phases of the HP. PMID

  19. Effects of dry, vacuum, and special bag aging; USDA quality grade; and end-point temperature on yields and eating quality of beef Longissimus lumborum steaks.

    PubMed

    Dikeman, Michael E; Obuz, Ersel; Gök, Veli; Akkaya, Levent; Stroda, Sally

    2013-06-01

    This study evaluated the effects of three aging methods: (dry (D), wet (W), and special bag (SB)); two quality grades [USDA Choice((≥Small(50) marbling) and Select); and two cooked end-point temperatures (62.8 °C and 71.1 °C) on physico-chemical traits of instrumental tenderness, color, and sensory properties of Longissimus lumborum beef muscle. Dry-aged loins had higher (P<0.0001) weight loss than W or SB aged loins. However, D and SB aged loins had similar (P>0.05) combined losses. W aged loins had higher (P<0.01) L* values than D or SB aged loins. Warner-Bratzler shear force of steaks was not affected (P>0.05) by aging method or quality grade but increased (P<0.0001) as end-point temperature increased. Sensory panel evaluation also showed no effect (P>0.05) of aging method or quality grade on myofibrillar tenderness, juiciness, connective tissue amount, overall tenderness or off flavor intensity. Steaks cooked to 62.8 °C were juicier (P<0.05) than those cooked to 71.1 °C. Neither D nor SB aging had advantages over W aging. PMID:23501255

  20. Deep burial dolomitization driven by plate collision: Evidence from strontium-isotopes of Jurassic Arab IV dolomites from offshore Qatar

    SciTech Connect

    Vahrenkamp, V.C.; Taylor, S.R. )

    1991-03-01

    The use of strontium-isotope ratios of dolomites to constrain timing and mechanism of diagenesis has been investigated on Jurassic Arab IV dolomites from offshore Qatar. Reservoir quality is determined by two types of dolomites, which were differentiated geochemically (cathodoluminescence, fluid inclusions, and carbon and oxygen stable isotopes): (1) stratigraphically concordant sucrosic dolomites with high porosity formed during early near-surface diagenesis (Jurassic) and (2) stratigraphically discordant cylindrical bodies of massive, porosity-destroying dolomites formed late during deep burial diagenesis (Eocene-Pliocene). Detailed Sr-isotope analysis of dolomites from the Arab IV confirms an Early Jurassic age of the sucrosic, high porosity dolomites ({sup 87}Sr/{sup 86}SR = 0.70707 for NBS 987 = 0.71024) with magnesium and strontium being derived from Jurassic seawater. Late Tertiary compressional orogeny of the Zagros belt to the north is proposed to have caused large-scale squeezing of fluids from the pore system of sedimentary rocks. A regional deep fluid flow system developed dissolving infra-Cambrian evaporites upflow and causing large-scale deep burial dolomitization downflow.

  1. Unraveling burial heating and sediment recycling in retroarc foreland basins: Detrital thermochronologic insights from the northern Magallanes Basin, Patagonian Andes

    NASA Astrophysics Data System (ADS)

    Fosdick, J. C.; Grove, M. J.; Graham, S. A.; Hourigan, J. K.; Lovera, O. M.; Romans, B.

    2014-12-01

    Sediment recycling is expected in many tectonic settings, such as foreland basins, where the path followed by grains initially derived from erosion of a basement source region typically involves significant intermediate stages of crustal evolution before the detritus is finally incorporated into tectonically stable basin strata. The shallow-crustal thermal histories experienced by eroded sediment may go undetected by traditional provenance methods but are potentially recoverable by thermochronologic methods. The Patagonian Magallanes retroarc foreland basin affords an excellent case study of sediment burial and recycling within a thrust belt setting. Combined detrital zircon U-Pb geochronology and (U-Th)/He thermochronology data and thermal modeling results confirm delivery of both rapidly cooled, first-cycle volcanogenic sediments from the Patagonian magmatic arc and recycled sediment from deeply buried and exhumed Cretaceous foredeep strata to the Cenozoic Magallanes basin depocenter. Numerical models of temperature-time histories indicate that ca. 54-45 Ma burial of the Maastrichtian Dorotea Formation produced 164-180°C conditions and heating to within the zircon He partial retention zone. Such deep burial is unusual for Andean foreland basins and may have resulted from combined effects of high basal heat flow and high sediment accumulation within a rapidly subsiding foredeep that was floored by basement weakened by previous Late Jurassic rifting. In this interpretation, Cenozoic thrust-related deformation deeply eroded the Dorotea Formation and underlying strata from ~5 km burial depths and may be associated with the development of a regionally extensive Paleogene unconformity. Results from the Cenozoic Río Turbio and Santa Cruz formations confirm that they contain both Cenozoic first-cycle zircon from the Patagonian magmatic arc and highly outgassed recycled zircon. This work suggests that Middle Miocene sediments were most likely derived from recycling of

  2. Temperature- and Age-Dependent Survival, Development, and Oviposition Rates of the Pupal Parasitoid Spalangia cameroni (Hymenoptera: Pteromalidae).

    PubMed

    Skovgård, Henrik; Nachman, Gösta

    2016-08-01

    The combined effect of temperature and age on development, survival, attack rate, and oviposition of the parasitoid Spalangia cameroni (Perkins) (Hymenoptera: Pteromalidae) exploiting house fly pupae was investigated by conducting life-table experiments at 15, 20, 25, 30 and 35°C. Temperature had a pronounced effect on survival and development of the immature stages. Survival was highest at 25°C, where 88.5% of the parasitized host pupae resulted in adult parasitoids, and lowest at 35°C when only 3.78% emerged. Females constituted between 50% (at 20°C) and 100% (at 35°C) of the surviving immatures. Males developed faster than females, with the shortest developmental times at 30°C (18.18 d for males and 19.41 d for females). Longevity of adult females decreased with temperature from 80 d at 15°C to 18 d at 35°C. Total attack rate of female parasitoids was highest at 20°C (106 hosts per female), and life-time reproduction highest at 20°C and 25°C (about 60 offspring per female). Sex ratio was female biased (65% females). A generic model was used to estimate and predict the temperature effect on the intrinsic rate of increase (rm), the net reproduction rate (R0), and the generation time (G). The model predicted that rm peaks at 33.5°C (rm = 0.182 d(-1)), that maximum R0 is reached at 27.2°C (R0 = 50.2), and that the shortest generation time occurs at 34.5°C (G = 21.1 d). Doubling time was 4.19 d at 33°C. In the temperature range between 20°C and 30°C, S. cameroni has the potential to be an efficient control agent against nuisance flies. PMID:27298392

  3. Effect of soil erosion on the long-term stability of FUSRAP near-surface waste-burial sites

    SciTech Connect

    Knight, M.J.

    1983-04-01

    Decontamination of FUSRAP sites could result in the generation of large volumes (in excess of 400,000 m/sup 3/) of low-activity radioactive wastes (primarily contaminated soil and building materials) requiring subsequent disposal. It is likely that near-surface burial will be seriously considered as an option for disposal of these materials. A number of factors - including soil erosion - could adversely affect the long-term stability of a near-surface waste-burial site. The majority of FUSRAP sites are located in the humid eastern United States, where the principal cause of erosion is the action of water. This report examines the effect of soil erosion by water on burial-site stability based on analysis of four hypothetical near-surface burial sites. The Universal Soil Loss Equation was employed to estimate average annual soil loss from burial sites and the 1000-year effects of soil loss on the soil barrier (burial trench cap) placed over low-activity wastes. Results suggest that the land use of the burial site and the slope gradient of the burial trench cap significantly affect the rate of soil erosion. The development of measures limiting the potential land use of a burial site (e.g., mixing large rocks into the burial trench cap) may be required to preserve the integrity of a burial trench for long periods of time.

  4. Effects of Temperature on the Age-Stage, Two-Sex Life Table of Bradysia odoriphaga (Diptera: Sciaridae).

    PubMed

    Li, Wenxiang; Yang, Yuting; Xie, Wen; Wu, Qingjun; Xu, Baoyun; Wang, Shaoli; Zhu, Xun; Wang, Shijun; Zhang, Youjun

    2015-02-01

    The demographics of Bradysia odoriphaga were examined with an age-stage, two-sex life table that was developed at 15, 20, 25, and 30°C under controlled conditions. The intrinsic rate of increase and mean generation time were 0.0574 and 48.08 d at 15°C, 0.1175 and 30.09 d at 20°C, 0.1369 and 26.31 d at 25°C, and 0.1247 and 26.55 d at 30°C, respectively. The gross reproductive rate (GRR), the net reproductive rate (R0), and the pre-adult survivorship (la) were consistent with the relationship R0temperatures. The mean duration of the total pre-adult stages was 38.01, 27.62, 23.74, and 24.10 d at 15, 20, 25, and 30°C, respectively. The highest values for the intrinsic rate of increase, finite rate of increase, and fecundity (0.1369 d(-1), 1.147 d(-1), and 50.53 eggs, respectively) and the shortest mean generation time were at 25°C. Still, B. odoriphaga was able to develop, survive, and reproduce across the entire temperature range (15-30°C). This study provides insight into the temperature-dependent phenology of B. odoriphaga and will contribute to the modeling of its population dynamics and to its management in the field. PMID:26470112

  5. Comparison of Graphite Fabric Reinforced PMR-15 and Avimid N Composites After Long Term Isothermal Aging at Various Temperatures

    NASA Technical Reports Server (NTRS)

    Bowles, Kenneth J.; McCorkle, Linda; Ingrahm, Linda

    1998-01-01

    Extensive effort is currently being expended to demonstrate the feasibility of using high-performance, polymer-matrix composites as engine structural materials over the expected operating lifetime of the aircraft, which can extend from 18,000 to 30,000 hr. The goal is to develop light-weight, high-strength, and high-modulus materials for use in higher temperature sections of advanced 21 st century aircraft propulsion systems. To accomplish this goal, it is necessary to pursue the development of thermal and mechanical durability models for graphite-fiber-reinforced, polymer-matrix composites. Numerous investigations have been reported regarding the thermo-oxidative stability (TOS) of the polyimide PMR-15 (1-5). A significant amount of this work has been directed at edge and geometry effects, reinforcement fiber influences, and empirical modeling of high-temperature weight loss behavior. It is yet to be determined if the information obtained from the PMR-15 composite tests is applicable to other polyimide-matrix composites. The condensation-curing polymer Avimid N is another advanced composite material often considered for structural applications at high temperatures. Avimid N has better thermo-oxidative stability than PMR-15 (6), but the latter is more easily processed. The most comprehensive study of the thermo-oxidative stability of Avimid N neat resin and composites at 371 (infinity)C is found in Salin and Seferis (7). The purposes of the work described herein were to compare the thermal aging behavior of these two matrix polymers and to determine the reasons for and the consequences of the difference in thermal durability. These results might be of some use in improving future polymer development through the incorporation of the desirable characteristics of both polyimides.

  6. A multi-proxy geochemical investigation of late-Quaternary paleoenvironmental change from Burial Lake, Noatak National Preserve, Alaska

    NASA Astrophysics Data System (ADS)

    Finkenbinder, M. S.; Abbott, M.; Stoner, J. S.; Dorfman, J. M.

    2012-12-01

    Here we present a new multi-proxy geochemical analysis of paleoenvironmental change inferred from sediment cores recovered from Burial Lake (68.434° N, 159.174° W; 430 m ASL) in northwest Alaska. Previous work on cores from 7.9 m water depth sampled at comparatively low resolution revealed basal sediments date to ~ 40,000 cal yr BP and an unconformity during a period of aridity around the Last Glacial Maximum (LGM). We therefore collected multiple overlapping Livingston cores from the lake depocenter (21.5 m water depth) in the summer of 2010 in an effort to develop a temporally continuous, high resolution record spanning prior to the LGM to the present. We focus our interpretations on a 6.51 m core developed through wiggle matching proxy data from core sites A10 and C10. We use traditional laboratory methods and investigate new approaches to assess changes in sedimentation and productivity. We are measuring dry bulk density, organic matter via Loss-on-ignition at 550° C, biogenic silica, magnetic susceptibility, grain size via laser diffractometry, and elemental abundances via scanning x-ray fluorescence (XRF). Future research seeks to test the reliability of two commonly used XRF proxies, for organic matter (incoherence/coherence ratios) and aquatic productivity (Si/Ti ratios). Age control is provided by 12 Accelerator Mass Spectrometry radiocarbon dates of discrete terrestrial macrofossils. Results from these analyses indicate that the depocenter core is continuous and the sediment record spans the last ~ 38,000 cal yr BP and most importantly contains sediments spanning the LGM. Preliminary geochemical results demonstrate substantial cyclicity in organic matter and aquatic productivity beginning in the late-glacial. We seek to analyze the periodicity of these proxies through spectral analysis, although initial observations suggest multi-century to millennial scale variability. In addition, we note the presence of two abrupt, non-linear transitions in organic

  7. A Protein Solvation Model Based on Residue Burial.

    PubMed

    Ceres, Nicoletta; Pasi, Marco; Lavery, Richard

    2012-06-12

    The influence of solvent on the individual amino acids of a protein depends not simply on their surface exposure but rather on the degree of their burial within the structure. This property can be related to a simple geometrical measure termed circular variance. Circular variance depends on the spatial distribution of neighboring residues and varies from zero to one as a residue becomes buried. Its only adjustable parameter is a cutoff distance for selecting neighbors. Here, we show that circular variance can be used to build a fast and effective model of protein solvation energies. For this, we combine a coarse-grain protein representation with statistical potentials derived by Boltzmann inversion of circular variance probability distributions for different classes of pseudoatom within a large protein structure database. The method is shown to work well for distinguishing native protein structures from decoy structures generated in a variety of ways. It can also be used to detect specific residues in unfavorable solvent environments. Compared to surface accessibility, circular variance calculations are faster, less sensitive to small conformational changes, and able to account for the longer-range interactions that characterize the electrostatic component of solvent effects. The resulting solvation energies can be used alone or as part of a more general coarse-grain protein model. PMID:26593844

  8. Carbon cycling and burial in New Zealand's fjords

    NASA Astrophysics Data System (ADS)

    Hinojosa, Jessica L.; Moy, Christopher M.; Stirling, Claudine H.; Wilson, Gary S.; Eglinton, Timothy I.

    2014-10-01

    carbon cycling in continental margin settings is critical for constraining the global carbon cycle. Here we apply a multiproxy geochemical approach to evaluate regional carbon cycle dynamics in six New Zealand fjords. Using carbon and nitrogen concentrations and isotopes, lipid biomarkers, and redox-sensitive element concentrations, we show that the New Zealand fjords have carbon-rich surface sediments in basins that promote long-term storage (i.e., semirestricted basins with sediment accumulation rates of up to 4 mm yr-1). Using δ13C distributions to develop a mixing model, we find that organic carbon in fjord sediments is well-mixed from marine and terrestrial sources in down-fjord gradients. This is driven by high regional precipitation rates of >6 m yr-1, which promote carbon accumulation in fjord basins through terrestrial runoff. In addition, we have identified at least two euxinic subbasins, based on uranium, molybdenum, iron, and cadmium enrichment, that contain >7% organic carbon. Because the strength and position of the Southern Hemisphere westerly winds control precipitation and fjord circulation, carbon delivery and storage in the region are intimately linked to westerly wind variability. We estimate that the fjord region (759 km2) may be exporting up to 1.4 × 107 kgC yr-1, outpacing other types of continental margins in rates of carbon burial by up to 3 orders of magnitude.

  9. The Dispersion and Burial of Well-Mixed Gravels

    NASA Astrophysics Data System (ADS)

    Haschenburger, J. K.

    2012-12-01

    Over the last two decades, results from numerous tracing experiments have shed light on grain kinematics in gravel-bed channels, including the distance of grain displacement and the depth of vertical mixing. However, most of these studies report results for relatively short temporal and spatial scales, when the behavior of tagged gravels may not reflect the overall streambed dynamics. The purpose of this talk is to highlight the grain kinematics of well-mixed gravels. Field observations come from a tracing experiment operated for nearly 20 years in Carnation Creek, which is located on the west coast of Vancouver Island, Canada. The small gravel-bed river with pool-riffle-bar morphology and large woody debris experiences an average of 15 ± 5 floods per year, which facilitates frequent streambed activity and relatively high bed material transport rates typically under partial sediment transport conditions. The magnetically tagged gravels, which range in size from 16 to 180 mm, have been recovered more than 10 times over the study period. Evaluation of the spatial distribution of tagged gravels over time documents the complex evolution of streamwise dispersion. Once tracers are well mixed vertically, the displacement of mobile gravels is only partly influenced by the tracer starting position in the bed morphology and its depth of burial before a given flooding period.

  10. Adventitious Root Production and Plastic Resource Allocation to Biomass Determine Burial Tolerance in Woody Plants from Central Canadian Coastal Dunes

    PubMed Central

    DECH, JEFFERY P.; MAUN, M. ANWAR

    2006-01-01

    • Background and Aims Burial is a recurrent stress imposed upon plants of coastal dunes. Woody plants are buried on open coastal dunes and in forested areas behind active blowouts; however, little is known about the burial responses and adaptive traits of these species. The objectives of this study were: (a) to determine the growth and morphological responses to burial in sand of seven woody plant species native to central Canadian coastal dunes; and (b) to identify traits that determine burial tolerance in these species. • Methods Field experiments were conducted to determine the responses of each species to burial. Saplings were exposed to burial treatments of 0, 10, 25, 50 and 75 % of their height. Burial responses were evaluated based on regressions of total biomass, height, adventitious root production and percentage allocation to shoot, root and adventitious root biomass on percentage burial. • Key Results Pinus strobus and Picea glauca lacked burial tolerance. In response to the burial gradient, these species showed a strong linear decline in total biomass, minimal adventitious root production that peaked at moderate levels (25–50 % burial) and no change in allocation to shoots vs. roots. The tolerant species Juniperus virginiana, Thuja occidentalis and Picea mariana showed a quadratic response to burial, with little change in biomass up to 50 % burial, but a large decline at 75 %. These species produced abundant adventitious roots up to 50 % burial, but did not alter allocation patterns over the range of burial levels. Populus balsamifera and Salix cordata were stimulated by burial. These species showed linear increases in biomass with increasing burial, produced copious adventitious roots across the gradient and showed a clear shift in allocation to vertical shoot growth and adventitious root production at the expense of the original roots under high burial conditions. • Conclusions Adventitious root production and plastic resource

  11. Littoral assessment of mine burial signatures (LAMBS): buried landmine/background spectral-signature analyses

    NASA Astrophysics Data System (ADS)

    Kenton, Arthur C.; Geci, Duane M.; Ray, Kristofer J.; Thomas, Clayton M.; Salisbury, John W.; Mars, John C.; Crowley, James K.; Witherspoon, Ned H.; Holloway, John H., Jr.

    2004-09-01

    The objective of the Office of Naval Research (ONR) Rapid Overt Reconnaissance (ROR) program and the Airborne Littoral Reconnaissance Technologies (ALRT) project's LAMBS effort is to determine if electro-optical spectral discriminants exist that are useful for the detection of land mines in littoral regions. Statistically significant buried mine overburden and background signature data were collected over a wide spectral range (0.35 to 14 μm) to identify robust spectral features that might serve as discriminants for new airborne sensor concepts. LAMBS has expanded previously collected databases to littoral areas - primarily dry and wet sandy soils - where tidal, surf, and wind conditions can severely modify spectral signatures. At AeroSense 2003, we reported completion of three buried mine collections at an inland bay, Atlantic and Gulf of Mexico beach sites. We now report LAMBS spectral database analyses results using metrics which characterize the detection performance of general types of spectral detection algorithms. These metrics include mean contrast, spectral signal-to-clutter, covariance, information content, and spectral matched filter analyses. Detection performance of the buried land mines was analyzed with regard to burial age, background type, and environmental conditions. These analyses considered features observed due to particle size differences, surface roughness, surface moisture, and compositional differences.

  12. Widespread mixing and burial of Earth's Hadean crust by asteroid impacts.

    PubMed

    Marchi, S; Bottke, W F; Elkins-Tanton, L T; Bierhaus, M; Wuennemann, K; Morbidelli, A; Kring, D A

    2014-07-31

    The history of the Hadean Earth (∼4.0-4.5 billion years ago) is poorly understood because few known rocks are older than ∼3.8 billion years old. The main constraints from this era come from ancient submillimetre zircon grains. Some of these zircons date back to ∼4.4 billion years ago when the Moon, and presumably the Earth, was being pummelled by an enormous flux of extraterrestrial bodies. The magnitude and exact timing of these early terrestrial impacts, and their effects on crustal growth and evolution, are unknown. Here we provide a new bombardment model of the Hadean Earth that has been calibrated using existing lunar and terrestrial data. We find that the surface of the Hadean Earth was widely reprocessed by impacts through mixing and burial by impact-generated melt. This model may explain the age distribution of Hadean zircons and the absence of early terrestrial rocks. Existing oceans would have repeatedly boiled away into steam atmospheres as a result of large collisions as late as about 4 billion years ago. PMID:25079556

  13. Littoral Assessment of Mine Burial Signatures (LAMBS) buried land mine/background spectral signature analyses

    USGS Publications Warehouse

    Kenton, A.C.; Geci, D.M.; Ray, K.J.; Thomas, C.M.; Salisbury, J.W.; Mars, J.C.; Crowley, J.K.; Witherspoon, N.H.; Holloway, J.H., Jr.

    2004-01-01

    The objective of the Office of Naval Research (ONR) Rapid Overt Reconnaissance (ROR) program and the Airborne Littoral Reconnaissance Technologies (ALRT) project's LAMBS effort is to determine if electro-optical spectral discriminants exist that are useful for the detection of land mines in littoral regions. Statistically significant buried mine overburden and background signature data were collected over a wide spectral range (0.35 to 14 ??m) to identify robust spectral features that might serve as discriminants for new airborne sensor concepts. LAMBS has expanded previously collected databases to littoral areas - primarily dry and wet sandy soils - where tidal, surf, and wind conditions can severely modify spectral signatures. At AeroSense 2003, we reported completion of three buried mine collections at an inland bay, Atlantic and Gulf of Mexico beach sites.1 We now report LAMBS spectral database analyses results using metrics which characterize the detection performance of general types of spectral detection algorithms. These metrics include mean contrast, spectral signal-to-clutter, covariance, information content, and spectral matched filter analyses. Detection performance of the buried land mines was analyzed with regard to burial age, background type, and environmental conditions. These analyses considered features observed due to particle size differences, surface roughness, surface moisture, and compositional differences.

  14. Fission-track ages from the Precambrian of Shropshire.

    USGS Publications Warehouse

    Naeser, C.W.; Toghill, P.; Ross, R.J., Jr.

    1982-01-01

    Four samples of Longmyndian and Uriconian strata from S of Shrewsbury, England have been processed for apatite and/or zircon fission-track ages. The resultant ages illustrate how depth of burial may affect fission-track ages. The analytical procedures followed were as described in Naeser (1979).-from Authors

  15. Miscellaneous information regarding operation and inventory of 618-11 Burial Ground

    SciTech Connect

    Webb, C.R.

    1993-06-01

    This report is a compilation of inventories and radiation surveys taken for the 618-11 Burial Ground at Hanford. This report deals with waste management activities at the facility during the early to mid-1960s.

  16. 38 CFR 3.1706 - Burial allowance for a veteran who died while hospitalized by VA.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... within a State, or to the border limits of the United States. (2) VA may pay the plot or interment allowance for burial in a veterans cemetery under § 3.1707, Plot or interment allowance. (Authority: 38...

  17. 38 CFR - § 3.1705 Burial allowance based on non-service-connected death.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... claim for, or award of, pension; and (2) VA may pay the plot or interment allowance for burial in a State veterans cemetery under § 3.1707(a), Plot or interment allowance. (Authority: 38 U.S.C. 2302,...

  18. 32 CFR 553.16 - Persons eligible for burial in Soldiers' Home National Cemetery.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES ARMY NATIONAL CEMETERIES § 553.16 Persons eligible for burial in Soldiers' Home National Cemetery. The Board of Commissioners of the US Soldiers'...

  19. 32 CFR 553.16 - Persons eligible for burial in Soldiers' Home National Cemetery.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES ARMY NATIONAL CEMETERIES § 553.16 Persons eligible for burial in Soldiers' Home National Cemetery. The Board of Commissioners of the US Soldiers'...

  20. 76 FR 31683 - Proposed Information Collection (NCA PreNeed Burial Evaluation) Activity: Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-01

    ...: National Cemetery Administration, Department of Veterans Affairs. ACTION: Notice. SUMMARY: The National Cemetery Administration (NCA), Department of Veterans Affairs (VA), is announcing an opportunity for public... claimant's eligibility for burial at a National Cemetery. DATES: Written comments and recommendations...

  1. Development and Application of a Paleomagnetic/Geochemical Method for Constraining the Timing of Burial Diagenetic Events

    SciTech Connect

    Elmore, Richard D.; Engel, Michael H.

    2006-01-05

    Studies of diagenesis caused by fluid migration or other events are commonly hindered by a lack of temporal control. Our results to date demonstrate that a paleomagnetic/geochemical approach can be used to date fluid migration as well as burial diagenetic events. Our principal working hypothesis is that burial diagenetic processes (e.g., maturation of organic-rich sediments and clay diagenesis) and the migration of fluids can trigger the authigenesis of magnetic mineral phases. The ages of these events can be constrained by comparing chemical remanent magnetizations (CRMs) to independently established Apparent Polar Wander Paths. Whilst geochemical (e.g. stable isotope and organic analyses) and petrographic studies provide important clues for establishing these relationships, the ultimate test of this hypothesis requires the application of independent dating methods to verify the paleomagnetic ages. Towards this end, we have used K-Ar dating of illitization as an alternative method for constraining the ages of magnetic mineral phases in our field areas. We have made significant progress toward understanding the origin and timing of chemical remagnetization related to burial diagenetic processes. For example, a recently completed field study documents a relationship between remagnetization and the maturation of organic matter (Blumstein et al., 2004). We have tested the hypothesized connection between clay diagenesis and remagnetization by conducting K-Ar dating of authigenic illites in units in Scotland and Montana with CRMs (e.g., Elliott et al., 2006a; Elliott et al., 2006b). We have also developed a fluid related model for alteration and remagnetization of Appalachian red beds that involves reduction and mobilization of iron phases by hydrocarbons and precipitation of authigenic hematite as a result of the introduction of meteoric fluid recharge (Cox et al., 2005). In addition, our recent studies of fluid-related CRMs along faults in Scotland provide information

  2. Improving burial practices and cemetery management during an Ebola virus disease epidemic - Sierra Leone, 2014.

    PubMed

    Nielsen, Carrie F; Kidd, Sarah; Sillah, Ansumana R M; Davis, Edward; Mermin, Jonathan; Kilmarx, Peter H

    2015-01-16

    As of January 3, 2015, Ebola virus disease (Ebola) has killed more than 2,500 persons in Sierra Leone since the epidemic began there in May 2014. Ebola virus is transmitted principally by direct physical contact with an infected person or their body fluids during the later stages of illness or after death. Contact with the bodies and fluids of persons who have died of Ebola is especially common in West Africa, where family and community members often touch and wash the body of the deceased in preparation for funerals. These cultural practices have been a route of Ebola transmission. In September 2014, CDC, in collaboration with the Sierra Leone Ministry of Health and Sanitation (MOH), assessed burial practices, cemetery management, and adherence to practices recommended to reduce the risk for Ebola virus transmission. The assessment was conducted by directly observing burials and cemetery operations in three high-incidence districts. In addition, a community assessment was conducted to assess the acceptability to the population of safe, nontraditional burial practices and cemetery management intended to reduce the risk for Ebola virus transmission. This report summarizes the results of these assessments, which found that 1) there were not enough burial teams to manage the number of reported deaths, 2) Ebola surveillance, swab collection, and burial team responses to a dead body alert were not coordinated, 3) systematic procedures for testing and reporting of Ebola laboratory results for dead bodies were lacking, 4) cemetery space and management were inadequate, and 5) safe burial practices, as initially implemented, were not well accepted by communities. These findings were used to inform the development of a national standard operating procedure (SOP) for safe, dignified medical burials, released on October 1. A second, national-level, assessment was conducted during October 10-15 to assess burial team practices and training and resource needs for SOP

  3. 3D GPR Modeling and Imaging of Burials: Mueschke Historic Cemetery, Houston, Texas

    NASA Astrophysics Data System (ADS)

    Abdul Aziz, A.; Stewart, R.; Green, S. L.

    2014-12-01

    3D ground-penetrating radar (GPR) surveys consisting of 6 grids were conducted from October 2013 until April 2014 to delineate burials at the historic Mueschke Cemetery in Houston, Texas. The surveys were primarily to assist historians and archeologists from the Mueschke Cemetery Association and Lone Star College in locating some 13 postulated unmarked burials. Antenna with three frequencies were used: 100 MHz, 250 MHz and 1000 MHz. Most surveys were conducted with the 250 MHz Sensors and Software NOGGIN System which has a maximum penetration of about 3 m. Three methods were used to estimate the soil velocity for time-to-depth conversion: Common mid-point (CMP) surveys, time-to-known depth matching, and hyperbola fitting. All three methods gave an average velocity of 0.06 m/ns in the upper 2 m of the soil. The time-to-known depth method was accomplished by digging a trench (1.5 m deep by 1.5 m wide by 3 m long) about 10 m from the cemetery entrance using a back-hoe. Rebar was hammered horizontally into the trench wall at 0.25 m increments from depths of 1.5 m to 0.25 m. The excavation also allowed us to observe soil strata which transitions from loam, to silty clay to mostly clay with increasing depth. We used finite-difference, time-domain computer modeling to synthesize the response of two types of burials: vaulted or concrete enclosed (post-1940) and non-vaulted or casket only (pre-1940). Modeling results indicate that vaulted burials have a flattened apex signature while non-vaulted burials have signatures that are more hyperbolic. The data were processed using gain, dewow, background removal, filtering, and migration. Survey data over known burials show distinct diffractions and a rectangular shape-correspondent to the computer modeling results. Burials before 1940 have weaker diffractions which complicates their detection. Tree roots, clay patches, and rocks can also present anomalies that must be carefully investigated. Nonetheless, several strong burial

  4. Particulate Organic Carbon Transport and Burial in the Colville River Delta, Beaufort Sea, Alaska

    NASA Astrophysics Data System (ADS)

    Bianchi, T. S.; Schreiner, K. M.; Rosenheim, B. E.; Allison, M.

    2013-12-01

    Terrestrial particulate organic carbon (tPOC) delivery to nearshore deltaic regions is an important mechanism of OC storage and burial, and river deltas and continental margins worldwide account for approximately 90% of the carbon burial in the ocean. The Arctic Ocean has the greatest percentage of continental shelf area as a proportion of total ocean basin area of any of the world's oceans, and receives freshwater and sediment from numerous large river systems. Increasing warming in the Arctic is leading to an acceleration of the hydrologic cycle, warming and breakdown of permafrost, and broad shifts in vegetation. All of these changes are likely to affect the delivery and burial of tPOC in nearshore regions. However, to date, most studies of tPOC delivery from North America to the Arctic Ocean have focused on large Arctic rivers like the Mackenzie and Yukon, and a significant portion of the watersheds of those rivers lie in sub-Arctic latitudes, indicating that their tPOC delivery is likely not representative of the high Arctic tundra. This study focuses on tPOC delivery by the Colville River, the largest North American river (in terms of both freshwater delivery and sediment load) with a watershed that does not include sub-Arctic latitudes. Sediment samples from the river delta and nearby Simpson's Lagoon were taken in August of 2010 and subsequently fractionated by density, in order to study the delivery of both discrete and sediment-sorbed tPOC. Samples were analyzed for stable carbon isotopes, bulk radiocarbon, terrestrial biomarkers (including lignin-phenols and non-lignin phenols, specifically those that are indicative of peat input), and aquatic biomarkers (algal pigments), and additionally a subset of the samples were analyzed by ramped pyrolysis-14C. Results show that tPOC delivery is concentrated near the river mouth sourced from coastal plain tundra, with additional delivery of tPOC from peat released into the lagoon from the seaward limit of the

  5. Electrical Resistivity Monitoring for Leachate Distribution at Two Foot-and-Mouth- Disease (FMD) Burial Sites

    NASA Astrophysics Data System (ADS)

    Lee, S.; Kaown, D.; Lee, K.; Leem, K.; Ko, K.

    2011-12-01

    The main objective of this study was to provide the basic information on leachate distribution with time changes through the electrical resistivity monitoring for a certain period of time in the Foot-and-Mouth-Disease (FMD) burial facilities which is needed to prevent further soil and groundwater contamination and to build an effective plan for stabilization of the burial site. In this study, dipole-dipoles surveys were carried out around two FMD burial sites in Iceon-si, Gyeonggi-do. The FMD burial facility installed at Daewall-myeon is consists of one block but, at Yul-myeon, it is divided into 2 blocks named A and B blocks. Dipole-Dipole surveys with 8 lines at Yul-myeon and 3 lines at Daewall-myeon were carried out. The observed leachate distribution along survey lines was not clearly evident as time passes at Daewall-myeon site, but, at Yul-myeon site, the leachate distribution around the survey lines showed a decrease of resistivity around the burial facility. At and around A and B blocks of Yul-myeon site, interpretations of the survey data show low resistivity zones below 10 Ωm from a depth 3 m to 10 m and such low resistivity zones of the A block are thicker than the B block by about 5~10 m. From the geochemical data and resistivity survey at two FMD burial sites, it is inferred that the groundwater within a 50-meter radius around burial facilities of the Yul-myeon site are contaminated by leachate. The general resistivity distribution around the burial site is seemed affected by the leachate with high electrical conductivity. The detail distribution patterns can be explained by local distributions of soil and weathered rocks and associated leachate flow. This subject is supported by Brain Korea 21 and Korea Ministry of Environment as 'The GAIA Project (173-092-009)'.

  6. Trend in groundwater quality near FMD burials in agricultural region, South Korea

    NASA Astrophysics Data System (ADS)

    Lim, Jeong-Won; Lee, Kang-Kun

    2015-04-01

    After the nation-wide outbreak of Foot and Mouth Disease (FMD) in winter of 2010-2011, thousands of mass burial site had been built all over the country in Korea. Though the burial pits were partially lined with impermeable material, potential threat of leachate leakage was still in concern. In worry of leachate release from those livestock burials during decomposition of carcasses, groundwater samples from wells near the burials were collected and analyzed in between 2011 and 2013. Among the sample locations, 250 wells with monitoring priorities were chosen and had been watched continuously through the years. For trend analysis of groundwater quality, relations between land use types, distances to burial and nitrate concentrations are studied. Types of land use within 300 m radius of each well were investigated. Nitrate concentrations show proportional relations to the area of agricultural activity and inversely proportional to the area of forest. The proportionality decreased with both agricultural and forest area since 2011. When seasonal variation is concerned, slightly stronger proportionality is shown in dry season for both agricultural and forested area. For a qualitative analysis of the trend, non-parametric Kendall test is applied. Especially, regional Kendall test is implemented to find out spatial feature of nitrate concentration. Nitrate concentrations show slow but statistically significant deceasing trend for every well. When the wells are group according to their distances from the nearest burial pit, decreasing trend of nitrate concentration is shown in all groups. However, there was no consistency in significant factor among the groups. Considering the above mentioned results, the groundwater wells near the burials seem to be influence more from agricultural activities near the wells than from the burial leachate. The slow but significant decreasing trend in nitrate concentration is supposed as the result of an increasing governmental interest in

  7. Cover integrity in shallow land burial of low-level wastes: hydrology and erosion

    SciTech Connect

    Lane, L.J.; Nyhan, J.W.

    1981-01-01

    Applications of a state-of-the-art technology for simulating hydrologic processes and erosion affecting cover integrity at shallow land waste burial sites are described. A nonpoint source pollution model developed for agricultural systems has been adapted for application to waste burial sites in semiarid and arid regions. Applications include designs for field experiments, evaluation of slope length and steepness, evaluation of various soil types, and evaluation of vegetative cover influencing erosion rates and the water balance within the soil profile.

  8. 133. ARAII SL1 burial ground. Shows gravel path from ARAII ...

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

    133. ARA-II SL-1 burial ground. Shows gravel path from ARA-II compound to the burial ground, detail of security fence and entry gate, and sign "Danger radiation hazard." F. C. Torkelson Company 842-area-101-1. Date: October 1961. Ineel index code no. 059-0101-00-851-150723. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

  9. Interactive effects of temperature and exo-enzyme age on substrate decay vary between C- and N-acquiring enzymes (Invited)

    NASA Astrophysics Data System (ADS)

    Billings, S. A.; Min, K.; Chen, Y.; Sellers, M.; Ballantyne, F.; Lehmeier, C.

    2013-12-01

    Decomposition of soil organic matter (SOM) is catalyzed by a vast array of exo-enzymes (EEs) produced by microorganisms and secreted into the soil matrix. The catalytic rate, i.e. the specific activity of an enzyme, typically declines with time after release, reducing the potential yield of assimilable resources from the enzyme. The rates at which EEs catalyze SOM decay is also influenced by the temperature at which the reactions proceed. The catalytic rates of functionally distinct enzymes (like carbon (C) or nitrogen (N) acquiring enzymes) show different responses to warming, leading to temperature-induced changes in relative liberation rates of C and N, and thus, in their relative availability for microbial acquisition. This effect might be amplified or mitigated by age-related decreases in catalytic rates, depending on how temperature affects the aging process of each enzyme. Although independent effects of temperature and age on enzyme kinetics have been established, how EE age interacts with temperature to influence the release of assimilable C and N is unknown. Because C vs. N limitation can influence microbial C economies, any interactive effects between temperature and EE age on substrate decay may be important determinants of microbial CO2 losses in a warming climate. Furthermore, quantifying effects of temperature on EE catalytic decline can provide insight into patterns of microbial decomposition strategies in changing temperature regimes. We determined specific activity rates of C-acquiring (β-glucosidase, BGase) and N-acquiring (N-acetyl-glucosaminidase, NAGase) enzymes immediately after EE reconstitution and at multiple time points thereafter (up to 2.5 d for NAGase, and up to 22 d for BGase), at multiple temperatures (5, 15, and 25°C), using fluorescently labeled substrates. We assume the moment of EE reconstitution represents the time of microbial EE exudation into the soil solution. Temperature influenced the catalytic decline of NAGase and

  10. Mechanical behavior of a Y-TZP ceramic for monolithic restorations: effect of grinding and low-temperature aging.

    PubMed

    Pereira, G K R; Silvestri, T; Camargo, R; Rippe, M P; Amaral, M; Kleverlaan, C J; Valandro, L F

    2016-06-01

    This study aimed to investigate the effects of grinding with diamond burs and low-temperature aging on the mechanical behavior (biaxial flexural strength and structural reliability), surface topography, and phase transformation of a Y-TZP ceramic for monolithic dental restorations. Disc-shaped specimens (Zirlux FC, Ivoclar Vivadent) were manufactured according to ISO 6872 (2008) and divided in accordance with two factors: "grinding - 3 levels" and "LTD - 2 levels". Grinding was performed using a contra-angle handpiece under constant water-cooling with different grit-sizes (extra-fine and coarse diamond burs). LTD was simulated in an autoclave at 134°C, under a pressure of 2 bar, over a period of 20h. Surface topography analysis showed an increase in roughness based on surface treatment grit-size (Coarse>Xfine>Ctrl), LTD did not influence roughness values. Both grinding and LTD promoted an increase in the amount of m-phase, although different susceptibilities to degradation were observed. According to existing literature the increase of m-phase content is a direct indicative of Y-TZP degradation. Weibull analysis showed an increase in characteristic strength after grinding (Coarse=Xfine>Ctrl), while for LTD, distinct effects were observed (Ctrlaging in autoclave for 20h (LTD) and grinding showed not to be detrimental to the mechanical properties of Zirlux FC Y-TZP ceramic. PMID:27040197

  11. Hydrology of the Melton Valley radioactive-waste burial grounds at Oak Ridge National Laboratory, Tennessee

    USGS Publications Warehouse

    Webster, D.A.; Bradley, Michael W.

    1988-01-01

    Burial grounds 4, 5, and 6 of the Melton Valley Radioactive-waste Burial Grounds, Oak Ridge, TN, were used sequentially from 1951 to the present for the disposal of solid, low level radioactive waste by burial in shallow trenches and auger holes. Abundant rainfall, a generally thin unsaturated zone, geologic media of inherently low permeability, and the operational practices employed have contributed to partial saturation of the buried waste, leaching of radionuclides, and transport of dissolved matter from the burial areas. Two primary methods of movement of wastes from these sites are transport in groundwater, and the overflow of fluid in trenches and subsequent flow across land surface. Whiteoak Creek and its tributaries receive all overland flow from trench spillage, surface runoff from each site, and discharge of groundwater from the regolith of each site. Potentiometric data, locally, indicate that this drainage system also receives groundwater discharges from the bedrock of burial ground 5. By projection of the bedrock flow patterns characteristic of this site to other areas of Melton Valley, it is inferred that discharges from the bedrock underlying burial grounds 4 and 6 also is to the Whiteoak Creek drainage system. The differences in potentiometric heads and a comparatively thin saturated zone in bedrock do not favor the development of deep flow through bedrock from one river system to another. (USGS)

  12. The cyclic deformation and fatigue behaviour of the low carbon steel SAE 1045 in the temperature regime of dynamic strain aging

    SciTech Connect

    Weisse, M.; Wamukwamba, C.K.; Christ, H.J.; Mughrabi, H. . Inst. fuer Werkstoffwissenschaften)

    1993-07-01

    The cyclic deformation behaviour of normalized SAE 1045 steel (german steel grade Ck 45) had been investigated over a range of temperatures between 20 and 375C. Special attention has been paid to the effects of dynamic strain aging, which are most pronounced around 300C. Different types of deformation tests (tension tests, incremental step tests, and constant amplitude cyclic deformation tests under stress control with a stress amplitude of 400 MPa as well as under plastic strain control with a plastic strain amplitude of 0.5%) were carried out to observe the influence of temperature on the macroscopic mechanical behaviour. These tests were followed by TEM studies on microstructural features. In the temperature range of maximum dynamic strain aging, the material was found to show maximum strength in unidirectional as well as in cyclic deformation tests. While the fatigue life is maximum at the temperature of maximum dynamic strain aging in stress-controlled tests, it is minimum in plastic strain controlled tests. At the temperature of maximum dynamic strain aging around 300C, the dislocations are arranged in dense dislocation tangles and parallel dislocation walls, whereas at room and at higher temperatures (375C) mainly dislocation cell structures are observed.

  13. Evidence of paleokarstic phenomena and burial diagenesis in Ordovician Arbuckle group of Oklahoma

    SciTech Connect

    Lynch, M.; Al-Shaieb, Z. )

    1989-08-01

    Cores from various localities in south-central and north-central Oklahoma display surprisingly similar suites of karstic and diagenetic phenomena. Vadose dissolution tubes, solution-enlarged fractures, collapse breccias, and vugular porosity, where present are considered evidence of karstification. Primary speleothemic precipitates were not readily observed; either they were not present or were obscured by later hydrothermal dolomitization. A complex history of exposure and subsidence is recorded in these rocks. Immature karst profiles may have subsided at rapid rates under conditions that prevented low-temperature phreatic cementation, thus preserving the open pore network of the karst profile. Deep burial diagenesis is evidenced by the appearance of highly ferroan baroque dolomite cement partially or entirely occluding vugular and fracture porosity. In addition, host-rock carbonates were extensively replaced by typical thermal xenomorphic dolomite. Cathodoluminescent microscopy indicates that the hydrothermal dolomite is uniform in composition and was precipitated under highly reducing conditions. Dolomite cementation was arrested when oil migrated into the remaining pore space. A complex multistage fracture network is present in cores from the Healdton oil field. Early fracture systems are healed by highly ferroan, dull luminescent baroque dolomite, and later fractures are cemented with nonferroan, brightly luminescent cement.

  14. Nonlinear geochemical dynamics and petrography: Burial dolomitization (Invited)

    NASA Astrophysics Data System (ADS)

    Merino, E.

    2010-12-01

    Many geochemical self-patterned structures exist in nature [1]: pisolitic, liesegang, orbicular, and agate bandings [2]; igneous and metamorphic bandings [3]; displacive dolomitic and serpentine “zebra” veins [4]; sets of stylolites [5]; oscillatory zoning in single crystals [6]. Large-scale examples: weathering profiles [7], banded iron formations [8], burial dolomitization [9], karst sinkholes [7]; etc. All involve disequilibrium and feedback, the two necessary conditions for self-patterning, but each case is unique. A good model should incorporate force(s), feedbacks, reactions, and boundary and initial conditions that are likely to apply to the genesis of the phenomenon under study. Problems: to confuse mass balances for local mineral reactions; whether the mineral pattern is made at a moving reaction front (as in agates [2]) or throughout the system at once (as in stylolitization [5] and zebra veins [4]). Self-consistent scaling of variables and linear instability analysis may tell us for what ranges of dynamic parameter values the system oscillates. A model may seem to work well - yet this does not prove that the initial choices of forcing, feedback and reactions were correct. Model predictions should be tested against petrographic and field evidence not used in constructing the model in the first place [2]. Recent models of dolomitization [10] and weathering are inconsistent with field and petrographic evidence. (P. K. Weyl, the first geochemical modeler: “We are not interested in what [a rock] is now but in how it became that way … Instead of looking at a rock and asking for an explanation of its past …”, J. Geophys. Res. 1959, p. 2001). A new dynamic model of dolomitization [9] correctly predicts a multitude of petrographic and other properties of burial dolostones. According to the model, the self-accelerating dolomite-for-calcite replacement forces a seamless rheological transition from replacive to displacive dolomite growth which predicts

  15. Use of controlled release herbicides in waste burial sites

    SciTech Connect

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

    1981-07-01

    Controlled-release formulations of herbicides have been applied to the soil in the manner traditional for herbicides: on the surface or mixed into the top few inches of soil. The controlled-release formulation allows another option that we propose to use: to place herbicides, contained in controlled-release formulations, in a layer at least a foot below the surface of the soil, in order to prevent root penetration below that level. Ideally, the herbicide will prevent root tip cell division but will not translocate within the plant, thus assuring that the plant will survive, preserving the ground cover. Trifluralin is one of the herbicides which does not translocate and was chosen for use in this study. A number of applications for this technology are possible; particularly in waste management. In the present studies, we used two different forms of polymeric carrier/delivery (PCD) systems to investigate the controlled release of herbicides. In the initial study, a sheet was made of homogeneous mixtures of an individual polymer and trifluralin. We made several of these sheets, using a different polymer each time (with trifluralin) to compare release rates from the various polymers. We also fabricated cylindrical pellets in two sizes from mixtures of Profax/sup a/ PS-1600 polypropylene and trifluralin, formulated to determine the interaction of PCD systems with soil. Also developed is a trifluralin-releasing device with a theoretical effective lifetime approaching 100 years. The system was designed specifically to protect the asphalt layer or clay/aggregate barriers on uranium mill tailings piles. PCD devices composed of pellets could also be implanted over burial sites for radioactive and/or toxic materials, preventing translocation of those materials to plant shoots, and thence into the biosphere.

  16. Dating floodplain sediments using tree-ring response to burial

    USGS Publications Warehouse

    Friedman, J.M.; Vincent, K.R.; Shafroth, P.B.

    2005-01-01

    Floodplain sediments can be dated precisely based on the change in anatomy of tree rings upon burial. When a stem of tamarisk (Tamarix ramosissima) or sandbar willow (Salix exigua) is buried, subsequent annual rings in the buried section resemble the rings of roots: rings become narrower, vessels within the rings become larger, and transitions between rings become less distinct. We combined observations of these changes with tree-ring counts to determine the year of deposition of sedimentary beds exposed in a 150-m-long trench across the floodplain of the Rio Puerco, a rapidly filling arroyo in New Mexico. This method reliably dated most beds thicker than about 30 cm to within a year of deposition. Floodplain aggradation rates varied dramatically through time and space. Sediment deposition was mostly limited to brief overbank flows occurring every few years. The most rapid deposition occurred on channel-margin levees, which migrated laterally during channel narrowing. At the decadal timescale, the cross-section-average sediment deposition rate was steady, but there was a shift in the spatial pattern of deposition in the 1980s. From 1936 to 1986, sediment deposition occurred by channel narrowing, with little change in elevation of the thalweg. After 1986 sediment deposition occurred by vertical aggradation. From 1936 to 2000 about 27 per cent of the arroyo cross-section filled with sediment. The rate of filling from 1962 to 2000 was 0-8 vertical m/decade or 85 m2/decade. Published in 2005 by John Wiley & Sons, Ltd.

  17. Vegetation uptake from burial ground alpha waste trenches

    SciTech Connect

    Murphy, C.E. Jr.; Tuckfield, R.C.

    1989-01-01

    This study was conducted as part of an evaluation of the potential radiological consequences of reinhabiting the SRS burial ground. The objective was to determine the uptake of buried, low-level, transuranic waste from unlined earthen trenches by forest vegetation. Two tree plots were established in 1979. One plot was put over a trench containing alpha waste and the other in an area without trenches. When the tree seedlings were sampled during 1979 and 1980, and analysized for {sup 239}Pu and {sup 238}Pu, there was only a small difference in radionuclude concentration between trees planted over the trench and those planted on the control plot because of the limited root intrusion into the trench by the seedlings. However, when trees were sample in 1986, 1987, and 1988 and analyzed for {sup 241}Am, {sup 238}Pu, {sup 239}Pu, and {sup 237}Np activity, the average activity of all of these isotopes was significantly higher over the trenches than in the control plot. These measurements indicate that tree roots will extract transuranic isotopes from buried, low-level waste. The amount of radioisotopes moved from the trenches to the surface is small and the level in the trees is low enough that dose from exposure will be small. The long term effects of transport of radioisotopes from the trenches to the surface soil was evaluated by estimating the accumulation in the surface soil. Transuranic activity in selected food crops was calculated using the soil activity and the literature derived concentration factors. In all cases, the activity of the transuranic isotopes in the edible portion of the plants was quite low. The activity in the leaf tissue was much higher than in the seed. However, it should be noted that in only one case was the activity higher than the naturally occurring activity of {sup 40}K in the pine foliage.

  18. Effect of rigor temperature, ageing and display time on the meat quality and lipid oxidative stability of hot boned beef Semimembranosus muscle.

    PubMed

    Mungure, Tanyaradzwa E; Bekhit, Alaa El-Din A; Birch, E John; Stewart, Ian

    2016-04-01

    The effects of rigor temperature (5, 15, 20 and 25°C), ageing (3, 7, 14, and 21 days) and display time on meat quality and lipid oxidative stability of hot boned beef M. Semimembranosus (SM) muscle were investigated. Ultimate pH (pH(u)) was rapidly attained at higher rigor temperatures. Electrical conductivity increased with rigor temperature (p<0.001). Tenderness, purge and cooking losses were not affected by rigor temperature; however purge loss and tenderness increased with ageing (p<0.01). Lightness (L*) and redness (a*) of the SM increased as rigor temperature increased (p<0.01). Lipid oxidation was assessed using (1)H NMR where changes in aliphatic to olefinic (R(ao)) and diallylmethylene (R(ad)) proton ratios can be rapidly monitored. R(ad), R(ao), PUFA and TBARS were not affected by rigor temperature, however ageing and display increased lipid oxidation (p<0.05). This study shows that rigor temperature manipulation of hot boned beef SM muscle does not have adverse effects on lipid oxidation. PMID:26773972

  19. Highly retentive core domains in K-feldspar preserve argon ages from high temperature stages of granite exhumation

    NASA Astrophysics Data System (ADS)

    Forster, Marnie; Lister, Gordon

    2016-04-01

    Retentive core domains are characterized by diffusion parameters that imply K-feldspar should be able to retain argon even at temperatures near or above the granite solidus. In this case it should be possible to date granite emplacement using argon geochronology, and the same answer should be obtained as by using other methods. We present one case study where this is the case, from the elevated Capoas granite stock on Palawan, in the Philippines, and another where it is not, from the South Cyclades Shear Zone, on Ios, Greece. We attempt to determine the factors such as the role of fluid ingress in triggering the in situ recrystallization that can eliminate and/or modify the core domains, leading to relatively youthful ages. Thermochronology is still possible, because less retentive diffusion domains exist, but different methods need to be applied to interpret the data. The work also demonstrates that K-feldspar can be sufficiently retentive as to allow direct dating of processes that reduce the dimensions of diffusion domains, e.g., cataclased and/or recrystallized K-feldspar in fault rock and/or mylonite. These are important developments in the methodology of 40Ar/39Ar geochronology, but to further advance we need to clarify the nature of these highly retentive core domains. In particular, we need better understand how they are modified by microstructural processes during deformation and metamorphism. We need also to assess the role of any crystal structural changes during step-heating in vacuo.

  20. Coal as a source rock of petroleum: A comparison between the petrology of the Mesaverde Group coals, in burial and hydrous pyrolysis

    SciTech Connect

    Garcia-Gonzalez, M.; Surdam, R.C. . Dept. of Geology and Geophysics)

    1992-01-01

    Almond Formation coal samples from the Upper Cretaceous Mesaverde Group, Greater Green River Basin, Wyoming, were studied to investigate the textural characteristics and maceral composition at different levels of maturation as observed through burial and hydrous pyrolysis experiments. The textural changes observed in these scenarios (burial and hydrous pyrolysis) are very similar and show a textural evolution that starts with the loss of the original laminated texture on desmocollinite, followed by the formation of a porous texture that evolves to a vesicular texture due to the generation of increasing quantities of exsudatinite, which can be considered as the precursor of petroleum. The maceral transformation starts with the formation of micrinite from liptinite, and at the same time desmocollinite becomes homogenized and the content of semifusinite and fusinite increases with increasing temperature in both burial and hydrous pyrolysis. The sources of exsudatinite in the Almond coal are the liptinite macerals and desmocollinite, which both contribute to the formation of vesicles filled by exsudatinite. When these vesicles are broken, the expulsion of oil from coal takes place. The recovery of liquid petroleum (as much as 27 mg oil/g coal) demonstrates that the Almond coal may be a significant source for oil in the Greater Green River Basin.

  1. Preferential burial of permafrost-derived organic carbon in Siberian-Arctic shelf waters

    NASA Astrophysics Data System (ADS)

    Vonk, Jorien E.; Semiletov, Igor P.; Dudarev, Oleg V.; Eglinton, Timothy I.; Andersson, August; Shakhova, Natalia; Charkin, Alexander; Heim, Birgit; Gustafsson, Örjan

    2014-12-01

    The rapidly changing East Siberian Arctic Shelf (ESAS) receives large amounts of terrestrial organic carbon (OC) from coastal erosion and Russian-Arctic rivers. Climate warming increases thawing of coastal Ice Complex Deposits (ICD) and can change both the amount of released OC, as well as its propensity to be converted to greenhouse gases (fueling further global warming) or to be buried in coastal sediments. This study aimed to unravel the susceptibility to degradation, and transport and dispersal patterns of OC delivered to the ESAS. Bulk and molecular radiocarbon analyses on surface particulate matter (PM), sinking PM and underlying surface sediments illustrate the active release of old OC from coastal permafrost. Molecular tracers for recalcitrant soil OC showed ages of 3.4-13 14C-ky in surface PM and 5.5-18 14C-ky in surface sediments. The age difference of these markers between surface PM and surface sediments is larger (i) in regions with low OC accumulation rates, suggesting a weaker exchange between water column and sediments, and (ii) with increasing distance from the Lena River, suggesting preferential settling of fluvially derived old OC nearshore. A dual-carbon end-member mixing model showed that (i) contemporary terrestrial OC is dispersed mainly by horizontal transport while being subject to active degradation, (ii) marine OC is most affected by vertical transport and also actively degraded in the water column, and (iii) OC from ICD settles rapidly and dominates surface sediments. Preferential burial of ICD-OC released into ESAS coastal waters might therefore lower the suggested carbon cycle climate feedback from thawing ICD permafrost.

  2. Subducted sedimentary serpentinite mélanges: Record of multiple burial-exhumation cycles and subduction erosion

    NASA Astrophysics Data System (ADS)

    Wakabayashi, John

    2012-09-01

    erosion may have facilitated reworking of forearc sedimentary serpentinite deposits into the trench. Evidence of multiple-burial exhumation cycles indicates reworking of subduction complex material, consistent with existence of clastic units that have fossils indicative of significantly older ages than detrital zircon ages.

  3. Evolution of the microstructure and hardness of a rapidly solidified/melt-spun AZ91 alloy upon aging at different temperatures

    SciTech Connect

    Wang Baishu; Liu Yongbing; An Jian; Li Rongguang; Su Zhenguo; Su Guihua; Lu You; Cao Zhanyi

    2009-04-15

    The effect of aging at different temperatures on a rapidly solidified/melt-spun AZ91 alloy has been investigated in depth. The microstructures of as-spun and aged ribbons with a thickness of approximately 60 {mu}m were characterized using X-ray diffraction, transmission electron microscopy and laser optical microscopy; microhardness measurements were also conducted. It was found that the commercial AZ91 alloy undergoes a cellular/dendritic transition during melt-spinning at a speed of 34 m/s. A strengthening effect due to aging was observed: a maximum hardness of 110 HV/0.05 and an age-hardenability of 50% were obtained when the ribbon was aged at 200 deg. C for 20 min. The {beta}-Mg{sub 17}Al{sub 12} phase exhibits net and dispersion types of distribution during precipitation. The dispersion of precipitates in dendritic grains or cells is the main source of strengthening.

  4. The effect of burial depth on removal of seeds of Phytolacca americana.

    SciTech Connect

    Orrock, John, L.: Damschen, Ellen, I.

    2007-04-01

    Abstract - Although burial is known to have important effects on seed predation in a variety of habitats, the role of burial depth in affecting the removal of seeds in early successional systems is poorly known. Phytolacca American (pokeweed) is a model species to examine the role of burial depth in affecting seed removal because it is common in early-successional habitats, studies suggest that seed removal is indicative of seed predation, and seed predation is related to the recruitment of mature plants. To determine how burial depth affects P. americana seed removal, 20 seeds of P. americana were buried at depths of 0, 1, or 3 cm in early-successional habitats at the Savannah River Site in South Carolina for over 6 weeks. The frequency with which seeds were encountered (as measured by the removal of at least one seed) and the proportion of seeds removed was significantly greater when seeds were on the soil surface (0 cm depth) compared to seeds that were buried 1 cm or 3 cm; there was no difference in encounter or removal between seeds at 1 cm or 3 cm. Our findings suggest that burial may have important consequences for P. americana population dynamics, because seed survival depends upon whether or not the seed is buried, and relatively shallow burial can yield large increases in seed survival. Because seed limitation is known to be an important determinant of plant community composition in early successional systems, our work suggests that burial may play an unappreciated role in the dynamics of these communities by reducing predator-mediated seed limitation.

  5. Field demonstration of in situ grouting of radioactive solid waste burial trenches with polyacrylamide. [Polyacrylamide

    SciTech Connect

    Spalding, B.P.; Fontaine, T.A.

    1990-01-01

    Demonstrations of in situ grouting with polyacrylamide were carried out on two undisturbed burial trenches and one dynamically compacted burial trench in Solid Waste Storage Area (SWSA) 6 at Oak Ridge National Laboratory (ORNL). The injection of polyacrylamide was achieved quite facilely for the two undisturbed burial trenches which were filled with grout, at typical pumping rates of 95 L/min, in several batches injected over several days. The compacted burial trench, however, failed to accept grout at more than 1.9 L/min even when pressure was applied. Thus, it appears that burial trenches, stabilized by dynamic compaction, have a permeability too low to be considered groutable. The water table beneath the burial trenches did not respond to grout injections indicating a lack of hydrologic connection between fluid grout and the water table which would have been observed if the grout failed to set. Because grout set times were adjusted to less than 60 min, the lack of hydrologic connection was not surprising. Postgrouting penetration testing revealed that the stability of the burial trenches was increased from 26% to 79% that measured in the undisturbed soil surrounding the trenches. In situ permeation tests on the grouted trenches indicated a significant reduction in hydraulic conductivity of the trench contents from a mean of 2.1 {times} 10{sup {minus}3} to 1.85 {times} 10{sup {minus}5} cm/s. Preliminary observations indicated that grouting with polyacrylamide is an excellent method for both improved stability and hydrologic isolation of radioactive waste and its incidental hazardous constituents.

  6. Molybdenum isotope signatures from the Yangtze block continental margin and its indication to organic burial rate

    NASA Astrophysics Data System (ADS)

    Zhou, L.; Zhou, H. B.; Huang, J. H.

    2007-12-01

    The paper presents the molybdenum isotope data, along with the trace element content, to investigate the geochemical behavior of authigenic Mo during long-term burial in sediments in continental margin settings of the Yangtze block, as well as their indication to the burial of original organic carbon. The burial rate of original organic carbon were estimated on the basis of the amount of sedimentary sulfur (TS content), whilst the carbon loss by aerobic degradation was estimated according to calculated Mn contents. On these points, the original organic carbon flux was calculated, exhibiting a large range of variation (2.54-15.82 mmol/m2/day). The strong correlation between sedimentary Mo isotope values and organic carbon burial rates previously proposed on the basis of the investigations on modern ocean sediments was also used here to estimate the organic carbon burial rate. The data gained through this model showed that organic carbon burial rates have large variations, ranging from 0.43- 2.87mmol/m2/day. Although the two sets of data gained through different geochemical records in the Yangtze block show a deviation of one order of magnitude, they do display a strong correlation. It is thus tempting to speculate that the Mo isotope signature of sediments may serve as a tracer for the accumulation rate of original organic carbon in the continental margin sediments. Keywords: Molybdenum isotopes; organic carbon burial rate; ancient continental margin setting ACKNOWLEDGMENTS We thank Professor Xie Shucheng for his constructive review comments. This research is co-supported by the Program for Changjiang Scholars and Innovative Research Team in University (grants IRT0441), the SinoPec project (grant no. G0800-06-ZS-319) and the National Nature Science Foundation of China (grants 40673020).

  7. Evaluation of Elevated Tritium Levels in Groundwater Downgradient from the 618-11 Burial Ground Phase I Investigations

    SciTech Connect

    Dresel, P.E.; Smith, R.M.; Williams, B.A.; Thompson, C.J.; Evans, J.C.; Hulstrom, L.C.

    2000-05-01

    This report describes the results of the preliminary investigation of elevated tritium in groundwater discovered near the 618-11 burial ground, located in the eastern part of the Hanford Site. Tritium in one well downgradient of the burial ground was detected at levels up to 8,140,000 pCi/L. The 618-11 burial ground received a variety of radioactive waste from the 300 Area between 1962 and 1967. The burial ground covers 3.5 hectare (8.6 acre) and contains trenches, large diameter caissons, and vertical pipe storage units. The burial ground was stabilized with a native sediment covering. The Energy Northwest reactor complex was constructed immediately east of the burial ground.

  8. Effects of aging temperature and time on the corrosion protection provided by trivalent chromium process coatings on AA2024-T3.

    PubMed

    Li, Liangliang; Swain, Greg M

    2013-08-28

    The effects of aging temperature and time on the physical structure of and corrosion protection provided by trivalent chromium process (TCP) coatings on AA2024-T3 are reported. The TCP coating forms a partially blocking barrier layer on the alloy surface that consists of hydrated channels and or defects. It is through these channels and defects that ions and dissolved O2 can be transported to small areas of the underlying alloy. Reactions initiate at these sites, which can ultimately lead to undercutting of the coating and localized corrosion. We tested the hypothesis that collapsing the channels and or reducing the number of defects in the coating might be possible through post-deposition heat treatment, and that this would enhance the corrosion protection provided by the coating. This was tested by aging the TCP-coated AA2024 alloys in air overnight at room temperature (RT), 55, 100, or 150 °C. The TCP coating became dehydrated and thinner at the high temperatures (55 and 100 °C). This improved the corrosion protection as evidenced by a 2× increase in the charge transfer resistance. Aging at 150 °C caused excessive coating dehydration and shrinkage. This led to severe cracking and detachment of the coating from the surface. The TCP-coated AA2024 samples were also aged in air at RT from 1 to 7 days. There was no thinning of the coating, but the corrosion protection was enhanced with a longer aging period as evidenced by a 4× increase in the charge transfer resistance. The coating became more hydrophobic after aging at elevated temperature (up to 100 °C) and with aging time at RT as evidenced by an increased water contact angle from 7 to 100 °C. PMID:23845106

  9. Development and Applications of Thallium isotopes: a new proxy tracking the extent of manganese oxide burial

    NASA Astrophysics Data System (ADS)

    Owens, J. D.; Nielsen, S.; Ostrander, C.; Peterson, L. C.; Anbar, A. D.

    2015-12-01

    Thallium (Tl) isotopes are a new and potential powerful paleoredox proxy with the possibility to track bottom water oxygen conditions based on the burial flux of manganese oxides. Thallium has a residence time of ~20 thousand years, which is long enough to render modern oxic seawater conservative with respect to concentration and isotopes. The isotopic signature of Tl in the global ocean is driven mainly by two outputs (1) adsorption onto manganese oxides and (2) low temperature oceanic crust alteration. Importantly, the isotopic inputs of Tl are all nearly the same value; thus, the isotopic composition and flux of the outputs almost exclusively set the seawater signature. For relatively short term redox events it is reasonable to assume that the dominant isotope fractionation process is associated with manganese oxide precipitation because low temperature alteration is controlled by long-term average ocean crust production rates. We present a broad range of modern samples that span several open ocean profiles combined with water column and sediment profiles from the permanently anoxic basins of the Black Sea and Cariaco Basins. The open ocean shows no variation in depth profiles that encompass most of the major water masses in the Atlantic and Southern Oceans. The anoxic basins, however, reveal Tl isotope signatures closer to their inputs, which is likely due to basinal restriction. The authigenic fraction of organic-rich sediments from the Black Sea and Cariaco Basin capture the Tl isotope value of the overlying water column, which shows that Tl isotopes could be applied as a faithful deep time redox proxy. For the first time, we will present new data showing that Tl isotopes is tracking bottom water ocean oxygenation. We are applying this isotope system to ancient samples, testing the spatial and temporal variability of ocean oxygenation coinciding with major biogeochemical events.

  10. Capture and sequestration of CO2 in the interlayer space of hydrated calcium Montmorillonite clay under various geological burial depth

    NASA Astrophysics Data System (ADS)

    Yang, W.; Zaoui, A.

    2016-05-01

    We perform, at nanoscale level, the structure and dynamics of carbon dioxide molecules in hydrated Ca-montmorillonite clays. The swelling behaviour of hydrated Wyoming-type Montmorillonite including CO2 molecules and counterions is presented and analysed. In addition, the atom density profile, diffusion behaviours and radial distribution functions of CO2, interlayer water molecules and Calcium ions have been investigated at different geological burial depth of 0 km, 3 km and 6 km, which correspond to various temperature and pressure of simulation conditions. Furthermore, the influence of different hydration state on the dynamical behaviours of carbon dioxide is also explained. The calculated self-diffusion coefficient shows that the carbon dioxide species diffuse more freely with the increase of depth and water content. We also found that the presence of interlayer CO2 inhibits the diffusion of all the mobile species. These results mainly show that the hydrated clay system is an appropriate space capable of absorbing CO2 molecules.

  11. Age-related changes in core body temperature and activity in triple-transgenic Alzheimer’s disease (3xTgAD) mice

    PubMed Central

    Knight, Elysse M.; Brown, Timothy M.; Gümüsgöz, Sarah; Smith, Jennifer C. M.; Waters, Elizabeth J.; Allan, Stuart M.; Lawrence, Catherine B.

    2013-01-01

    SUMMARY Alzheimer’s disease (AD) is characterised, not only by cognitive deficits and neuropathological changes, but also by several non-cognitive behavioural symptoms that can lead to a poorer quality of life. Circadian disturbances in core body temperature and physical activity are reported in AD patients, although the cause and consequences of these changes are unknown. We therefore characterised circadian patterns of body temperature and activity in male triple transgenic AD mice (3xTgAD) and non-transgenic (Non-Tg) control mice by remote radiotelemetry. At 4 months of age, daily temperature rhythms were phase advanced and by 6 months of age an increase in mean core body temperature and amplitude of temperature rhythms were observed in 3xTgAD mice. No differences in daily activity rhythms were seen in 4- to 9-month-old 3xTgAD mice, but by 10 months of age an increase in mean daily activity and the amplitude of activity profiles for 3xTgAD mice were detected. At all ages (4–10 months), 3xTgAD mice exhibited greater food intake compared with Non-Tg mice. The changes in temperature did not appear to be solely due to increased food intake and were not cyclooxygenase dependent because the temperature rise was not abolished by chronic ibuprofen treatment. No β-amyloid (Aβ) plaques or neurofibrillary tangles were noted in the hypothalamus of 3xTgAD mice, a key area involved in temperature regulation, although these pathological features were observed in the hippocampus and amygdala of 3xTgAD mice from 10 months of age. These data demonstrate age-dependent changes in core body temperature and activity in 3xTgAD mice that are present before significant AD-related neuropathology and are analogous to those observed in AD patients. The 3xTgAD mouse might therefore be an appropriate model for studying the underlying mechanisms involved in non-cognitive behavioural changes in AD. PMID:22864021

  12. Investigating the Impact of Temperature Changes, Material Aging, and Service Load on the Strain of a Reinforced Concrete Construction

    NASA Astrophysics Data System (ADS)

    Kanciruk, Adam

    2014-12-01

    Intensive exploitation of coal beds in the Upper Silesia Coal Basin led to the degradation of the Katowice-Muchowiec civilian/military airport. As a result, it became necessary to adapt the Pyrzowice military airport for use as a public transport facility. This involved reconstruction of a hangar located at the airport. As part of this process, a new hangar slab was constructed, designed in such a way as to bear the load of passenger aircraft. In the area of the greatest wheel load to the slab, three strain rosettes were installed for the purpose of monitoring the slab strain. The mointoring process - which has been automatically conducted for almost three years now - revealed deformations resulting from service load, the aging of reinforced concrete, and changes of its temperature. Intensywna eksploatacja górnośląskich złóż węgla doprowadziła do degradacji cywilno-wojskowego lotniska Katowice-Muchowiec. W związku z tym, wynikła konieczność przystosowania do celów komunikacyjnych lotniska wojskowego w Pyrzowicach, w tym przebudowy znajdującego się na jego terenie hangaru. W ramach przebudowy wykonano nową posadzkę, zdolną przenosić ciężar samolotów pasażerskich. W posadzce tej, w rejonie występowania największych nacisków zainstalowano 3 rozety tensometryczne w celu monitorowania jej odkształceń. Monitorowanie to, prowadzone w sposób automatyczny już niemal 3 lata, wykazało występowanie odkształceń będących skutkiem obciążeń eksploatacyjnych, starzenia się żelbetu oraz zmian jego temperatury.

  13. Water Intake by Outdoor Temperature Among Children Aged 1–10 Years: Implications for Community Water Fluoridation in the U.S.

    PubMed Central

    Beltrán-Aguilar, Eugenio D.; Sohn, Woosung; Wei, Liang

    2015-01-01

    Objective The U.S. water fluoridation recommendations, which have been in place since 1962, were based in part on findings from the 1950s that children's water intake increased with outdoor temperature. We examined whether or not water intake is associated with outdoor temperature. Methods Using linked data from the National Health and Nutrition Examination Survey (NHANES) 1999–2004 and the National Oceanic and Atmospheric Administration, we examined reported 24-hour total and plain water intake in milliliters per kilogram of body weight per day of children aged 1–10 years by maximum outdoor temperature on the day of reported water intake, unadjusted and adjusted for age, sex, race/ethnicity, and poverty status. We applied linear regression methods that were used in previously reported analyses of data from NHANES 1988–1994 and from the 1950s. Results We found that total water intake was not associated with temperature. Plain water intake was weakly associated with temperature in unadjusted (coefficient 5 0.2, p=0.015) and adjusted (coefficient 5 0.2, p=0.013) linear regression models. However, these models explained little of the individual variation in plain water intake (unadjusted: R2=0.005; adjusted: R2=0.023). Conclusion Optimal fluoride concentration in drinking water to prevent caries need not be based on outdoor temperature, given the lack of association between total water intake and outdoor temperature, the weak association between plain water intake and outdoor temperature, and the minimal amount of individual variance in plain water intake explained by outdoor temperature. These findings support the change in the U.S. Public Health Service recommendation for fluoride concentration in drinking water for the prevention of dental caries from temperature-related concentrations to a single concentration that is not related to outdoor temperature. PMID:26346578

  14. Unbalanced discharging and aging due to temperature differences among the cells in a lithium-ion battery pack with parallel combination

    NASA Astrophysics Data System (ADS)

    Yang, Naixing; Zhang, Xiongwen; Shang, BinBin; Li, Guojun

    2016-02-01

    This paper presents an investigation on the unbalanced discharging and aging due to temperature difference between the parallel-connected cells. A thermal-electrochemical model is developed for the parallel-connected battery pack. The effects of temperature difference on the unbalanced discharging performances are studied by simulations and experiments. For the parallel-connected cells, the cell at higher temperature experiences a larger current in the early discharging process before approximately 75% of depth of discharge (DOD). When the discharge process approaches the voltage turn point of the battery pack, the discharge current through the cell at higher temperature begins to decrease significantly. After the DOD reaches approximately 90%, the discharge current of the cell at higher temperature rises again. Correspondingly, the changes in the discharging current through the cell at lower temperature are opposite to that of the cell at higher temperature. Simulations also show that the temperature difference between the parallel-connected cells greatly aggravates the imbalance discharge phenomenon between the cells, which accelerates the losses of the battery pack capacity. For the parallel-connected battery pack, the capacity loss rate approximately increases linearly as the temperature difference between the cells increases. This trend is magnified with the increase of operating temperature.

  15. Awn length variation and its effect on dispersal unit burial of Trachypogon spicatus (Poaceae).

    PubMed

    Johnson, Erica E; Baruch, Zdravko

    2014-03-01

    Trachypogon spicatus, formerly known as Trachypogon plumosus, is a dominant grass in some savannas of Northern South America. Its dispersal unit, like many other species of the Andropogoneae tribe, bears a hygroscopic awn which facilitates its establishment in favorable microsites. Some authors have previously proposed that there is a positive correlation between awn length and dispersal unit burial, and that this relationship increases the probability of seed survival in the event of a fire, since soil acts as insulator. In this study we experimentally tested this relationship for T. spicatus. A total of 192 diaspores were placed in randomized blocks, in aluminum trays filled with soil under greenhouse conditions. Diaspores were sprayed with water daily for a month to guarantee awn movement; on the last day of the experiment, they were sprayed with red aerosol paint to determine burial depth. The effects of awn length, presence of caryopses, and presence of a pivot for the passive segment of the awn on diaspore burial were evaluated. Germination viability was tested using a tetrazolium salt test for 35 caryopses. No significant differences in diaspore burial were observed between diaspores with and without caryopses (F(2,126) = 0.034, p=0.853). A positive correlation between awn length and diaspore burial was observed only if the passive awn lacked a pivot (r(66)=0.394, p<0.05). Diaspores whose awns had a pivot point achieved significantly deeper burial distances than their counterparts (F(2,126)=7.063, p=0.005). Viability test found that 0% of caryopses tested were able to germinate; this is possibly due to the time difference between sampling and testing. We considered the presence or absence of caryopsis as an important factor, since previous studies have not yet considered it and the high production of sterile diaspores in grasses. These results suggest that the physical mechanism behind T. spicatus diaspore burial is awn torque. This would explain why our

  16. Measurement of Helium-3/Helium-4 Ratios in Soil Gas at the 618-11 Burial Ground

    SciTech Connect

    Olsen, Khris B.; Dresel, P Evan; Evans, John C.

    2001-10-31

    Seventy soil gas-sampling points were installed around the perimeter of the 618-11 Burial Ground, approximately 400 feet downgradient of well 699-13-3A, and in four transects downgradient of the burial ground to a maximum distance of 3,100 feet. Soil gas samples were collected and analyzed for helium-3/helium-4 ratios from these 70 points. Helium-3/helium-4 ratios determined from the soil gas sampling points showed significant enrichments, relative to ambient air helium-3 concentrations. The highest concentrations were located along the northern perimeter of the burial ground. Helium-3/helium-4 ratios (normalized to the abundances in ambient air) ranged from 1.0 to 62 around the burial ground. The helium-3/helium-4 ratios from the 4 transect downgradient of the burial ground ranged from 0.988 to 1.68. The helium-3/helium-4 ratios from around the burial ground suggest there is a vadose zone source of tritium along the north side of the burial ground. This vadose zone source is likely the source of tritium in the groundwater. The helium-3/helium-4 ratios also suggest the groundwater plume is traveling east-northeast from the burial ground and the highest groundwater tritium value may be to the north of well 699-13-3A. Finally, there appears to be no immediately upgradient sources of tritium impacting the burial ground since all the upgradient helium-3/helium-4 ratios are approximately 1.0.

  17. Controlled preparation of wet granular media reveals limits to lizard burial ability.

    PubMed

    Sharpe, Sarah S; Kuckuk, Robyn; Goldman, Daniel I

    2015-07-01

    Many animals move within ground composed of granular media (GM); the resistive properties of such substrates can depend on water content and compaction, but little is known about how such parameters affect locomotion or the physics of drag and penetration. Using apparatus to control compaction of GM, our recent studies of movement in dry GM have revealed locomotion strategies of specialized dry-sand-swimming reptiles. However, these animals represent a small fraction of the diversity and presumed burial strategies of fossorial reptilian fauna. Here we develop a system to create states of wet GM of varying moisture content and compaction in quantities sufficient to study the burial and subsurface locomotion of the Ocellated skink (C. ocellatus), a generalist lizard. X-ray imaging revealed that in wet and dry GM the lizard slowly buried (≈30 s) propagating a wave from head to tail, while moving in a start-stop motion. During forward movement, the head oscillated, and the forelimb on the convex side of the body propelled the animal. Although body kinematics and 'slip' were similar in both substrates, the burial depth was smaller in wet GM. Penetration and drag force experiments on smooth cylinders revealed that wet GM was ≈4× more resistive than dry GM. In total, our measurements indicate that while the rheology of the dry and wet GM differ substantially, the lizard's burial motor pattern is conserved across substrates, while its burial depth is largely constrained by environmental resistance. PMID:26109565

  18. Controlled preparation of wet granular media reveals limits to lizard burial ability

    NASA Astrophysics Data System (ADS)

    Sharpe, Sarah S.; Kuckuk, Robyn; Goldman, Daniel I.

    2015-07-01

    Many animals move within ground composed of granular media (GM); the resistive properties of such substrates can depend on water content and compaction, but little is known about how such parameters affect locomotion or the physics of drag and penetration. Using apparatus to control compaction of GM, our recent studies of movement in dry GM have revealed locomotion strategies of specialized dry-sand-swimming reptiles. However, these animals represent a small fraction of the diversity and presumed burial strategies of fossorial reptilian fauna. Here we develop a system to create states of wet GM of varying moisture content and compaction in quantities sufficient to study the burial and subsurface locomotion of the Ocellated skink (C. ocellatus), a generalist lizard. X-ray imaging revealed that in wet and dry GM the lizard slowly buried (≈ 30 s) propagating a wave from head to tail, while moving in a start-stop motion. During forward movement, the head oscillated, and the forelimb on the convex side of the body propelled the animal. Although body kinematics and ‘slip’ were similar in both substrates, the burial depth was smaller in wet GM. Penetration and drag force experiments on smooth cylinders revealed that wet GM was ≈ 4× more resistive than dry GM. In total, our measurements indicate that while the rheology of the dry and wet GM differ substantially, the lizard's burial motor pattern is conserved across substrates, while its burial depth is largely constrained by environmental resistance.

  19. Age-related changes in amino acid pool sizes in the adult silkmoth, Bombyx mori, reared at low and high temperature; a biochemical examination of the rate-of-living theory and urea accumulation when reared at high temperature.

    PubMed

    Osanai, M; Yonezawa, Y

    1984-01-01

    To examine the rate-of-living theory, age-related changes in amino acid pool sizes were investigated in the adult silkmoth, Bombyx mori, reared at low and high temperature. At either temperature concentrations of free amino acids contained in silkmoths revealed a great sexual difference. Those in females were generally much higher than in males and the former changed much more dynamically than the latter. Major amino acids or ninhydrin-positive compounds inclusive of some essential amino acids such as Leu, Ile, Val, Thr, Arg, Phe, Met, Ala, Tyr, Gln, Aspn , Lan , Cysta , GABA and PEA accumulated in 4 degrees C-moths. However, the levels of these amino changed irregularly with advanced age. Inhibition of protein synthesis may occur generally at low temperature, while protein degradation may be promoted at high temperature. High concentrations of MSO and Tau in the moths reared at high temperature than in the normal moths suggested also catabolism of amino acids proceeding together with protein degradation at high temperature. Amino acid metabolism seems to be complicated under various temperature conditions. When reared at the optimal temperature of 25 degrees C, urea is not present in the body of the silkmoth except for a slight amount in the secreted meconium. In silkmoths reared at the higher temperature of 35 degrees C, however, an extraordinary accumulation of urea occurs accompanied by a reduction in lifespan by one half. Undoubtedly, urea is produced in this terrestrial insect, although the accumulation mechanism is not clear: in silkmoths reared at various temperatures, arginase is found, but urease is not detected. Arginase activity was found to be higher in male moths than in female moths regardless of the rearing temperature. High temperature rearing also did not induce activity and female activity never exceeded that in males at either 25 degrees C or 35 degrees C rearing. Protein degradation accelerated by rearing at high temperatures may result in

  20. Daily rhythms of core temperature and locomotor activity indicate different adaptive strategies to cold exposure in adult and aged mouse lemurs acclimated to a summer-like photoperiod.

    PubMed

    Terrien, Jeremy; Zizzari, Philippe; Epelbaum, Jacques; Perret, Martine; Aujard, Fabienne

    2009-07-01

    Daily variations in core temperature (Tc) within the normothermic range imply thermoregulatory processes that are essential for optimal function and survival. Higher susceptibility towards cold exposure in older animals suggests that these processes are disturbed with age. In the mouse lemur, a long-day breeder, we tested whether aging affected circadian rhythmicity of Tc, locomotor activity (LA), and energy balance under long-day conditions when exposed to cold. Adult (N = 7) and aged (N = 5) mouse lemurs acclimated to LD14/10 were exposed to 10-day periods at 25 and 12 degrees C. Tc and LA rhythms were recorded by telemetry, and caloric intake (CI), body mass changes, and plasma IGF-1 were measured. During exposure to 25 degrees C, both adult and aged mouse lemurs exhibited strong daily variations in Tc. Aged animals exhibited lower levels of nocturnal LA and nocturnal and diurnal Tc levels in comparison to adults. Body mass and IGF-1 levels remained unchanged with aging. Under cold exposure, torpor bout occurrence was never observed whatever the age category. Adult and aged mouse lemurs maintained their Tc in the normothermic range and a positive energy balance. All animals exhibited increase in CI and decrease in IGF-1 in response to cold. The decrease in IGF-1 was delayed in aged mouse lemurs compared to adults. Moreover, both adult and aged animals responded to cold exposure by increasing their diurnal LA compared to those under Ta = 25 degrees C. However, aged animals exhibited a strong decrease in nocturnal LA and Tc, whereas cold effects were only slight in adults. The temporal organization and amplitude of the daily phase of low Tc were particularly well preserved under cold exposure in both age groups. Sexually active mouse lemurs exposed to cold thus seemed to prevent torpor exhibition and temporal disorganization of daily rhythms of Tc, even during aging. However, although energy balance was not impaired with age in mouse lemurs after cold exposure

  1. Effect of pre-oxidation and environmental aging on the seal strength of a novel high-temperature solid oxide fuel cell (SOFC) sealing glass with metallic interconnect

    SciTech Connect

    Chou, Y. S.; Stevenson, Jeffry W.; Singh, Prabhakar

    2008-09-15

    A novel high-temperature alkaline-earth silicate sealing glass was developed for solid oxide fuel cell (SOFC) applications. The glass was used to join two ferritic stainless steel coupons for strength evaluation. The steel coupons were pre-oxidized at elevated temperatures to promote thick oxide layers to simulate long-term exposure conditions. In addition, seals to as-received metal coupons were also tested after aging in oxidizing or reducing environments to simulate the actual SOFC environment. Room temperature tensile testing showed strength degradation when using pre-oxidized coupons, and more extensive degradation after aging in air. Fracture surface and microstructural analysis confirmed that the cause of degradation was formation of SrCrO4 at the outer sealing edges exposed to air.

  2. Effect of pre-oxidation and environmental aging on the seal strength of a novel high-temperature solid oxide fuel cell (SOFC) sealing glass with metallic interconnect

    NASA Astrophysics Data System (ADS)

    Chou, Yeong-Shyung; Stevenson, Jeffry W.; Singh, Prabhakar

    A novel high-temperature alkaline-earth silicate sealing glass was developed for solid oxide fuel cell (SOFC) applications. The glass was used to join two ferritic stainless steel coupons for strength evaluation. The steel coupons were pre-oxidized at elevated temperatures to promote thick oxide layers to simulate long-term exposure conditions. In addition, seals to as-received metal coupons were also tested after aging in oxidizing or reducing environments to simulate the actual SOFC environment. Room temperature tensile testing showed strength degradation when using pre-oxidized coupons, and more extensive degradation after aging in air. Fracture surface and microstructural analysis confirmed that the cause of degradation was formation of SrCrO 4 at the outer sealing edges exposed to air.

  3. Deep burial diagenesis in Rotliegende reservoirs of the NW German Basin

    SciTech Connect

    Ramseyer, K. ); Gaupp, R.; Matter, A.

    1990-05-01

    A deeply buried Permian continental sequence forms the major gas reservoir in northwest Germany. Deposits of fluvial, eolian, and playa lake shoreline facies show the most favorable reservoir properties. Burial diagenesis is greatly influenced by primary depositional textures and eogenetic processes. However, growth of authigenic clay minerals (illite, kaolinite/dickite, chlorite) relates to changes in the chemistry and flow rate of formation waters. Three different mesogenetic fluid types can be recognized: (1) Alkaline fluids from basin center red beds: The presence of pore-lining chlorite in porous subarkoses of the playa shoreline facies probably is related to a compaction-driven influx of alkaline waters from the shaly, red bed sequences of the basin center. (2) Acidic fluids from coal-bearing Late Carboniferous sediments: An aureole of dickite/kaolinite, several hundred meters wide, is developed in Rotliegende arkosic sands where they are juxtaposed against Carboniferous horsts. In this zone, almost all feldspars were destroyed and the formation of dickite/kaolinite was followed by illite growth and bitumen impregnation. In an outer aureole with less extensive feldspar destruction, kandite minerals are not present, but a dense meshwork of well-crystallized, platy illite fills the pores. The intensity of illitization diminishes away from the Carboniferous sediments (i.e., with increasing distance of fluid migration). K-Ar ages reveal that this illite precipitated within a period when organic maturation products were expelled from the coal measures into Rotliegende sediments and when Paleozoic faults were reactivated. (3) Brines from overlying Zechstein evaporites: During late mesogenetic uplift local influxes of these brines resulted in the formation of pore-plugging carbonate and sulfate cements.

  4. Timing of compaction and quartz cementation from integrated petrographic and burial-history analyses, Lower Cretaceous Fall River Formation, Wyoming and South Dakota

    SciTech Connect

    Dutton, S.P.

    1997-01-01

    Integrated petrographic and burial-history studies of Fall River sandstones from outcrop and the subsurface provide insight into the timing of compaction and quartz cementation, the two main porosity-reducing processes in quartzose sandstones. Petrographic study of 95 thin sections of Fall River fluvial valley-fill sandstones from outcrop, Donkey Creek field at 2 km burial depth, and Buck Draw field at 3.8 km indicates that reservoir quality differs significantly in these three areas. Fall River sandstones at the surface contain an average of 31% intergranular volume (IGV) and 2% quartz cement. In both Donkey Creek and Buck Draw fields, the sandstones average 22% IGV, but quartz-cement volume averages 8% in the shallower field and 12% in the deeper. Geometric mean permeability at the surface is 4,700 md, compared with 42 md at 2 km and 2 md at 3.8 km. Burial history of the Fall River sandstone differs greatly in the three areas. The outcropping sandstones were buried to 2 km and had reached 80 C by the end of the Cretaceous. They were then uplifted and have remained at near-surface temperatures since the Paleocene; the calculated time-temperature index (TTI) of these sandstones is 1. Fall River sandstones at Donkey Creek were also buried to 2 km and had reached 80 C by the end of the Cretaceous but remained at that depth during the Tertiary; TTI is 14. In Buck Draw field, Fall River sandstones were buried to 2.5 km during the Cretaceous and then continued to subside during the Tertiary, reaching depths of 4 km and temperatures of 140 C; TTI is 512.

  5. Global pulses of organic carbon burial in deep-sea sediments during glacial maxima.

    PubMed

    Cartapanis, Olivier; Bianchi, Daniele; Jaccard, Samuel L; Galbraith, Eric D

    2016-01-01

    The burial of organic carbon in marine sediments removes carbon dioxide from the ocean-atmosphere pool, provides energy to the deep biosphere, and on geological timescales drives the oxygenation of the atmosphere. Here we quantify natural variations in the burial of organic carbon in deep-sea sediments over the last glacial cycle. Using a new data compilation of hundreds of sediment cores, we show that the accumulation rate of organic carbon in the deep sea was consistently higher (50%) during glacial maxima than during interglacials. The spatial pattern and temporal progression of the changes suggest that enhanced nutrient supply to parts of the surface ocean contributed to the glacial burial pulses, with likely additional contributions from more efficient transfer of organic matter to the deep sea and better preservation of organic matter due to reduced oxygen exposure. These results demonstrate a pronounced climate sensitivity for this global carbon cycle sink. PMID:26923945

  6. Global pulses of organic carbon burial in deep-sea sediments during glacial maxima

    PubMed Central

    Cartapanis, Olivier; Bianchi, Daniele; Jaccard, Samuel L.; Galbraith, Eric D.

    2016-01-01

    The burial of organic carbon in marine sediments removes carbon dioxide from the ocean–atmosphere pool, provides energy to the deep biosphere, and on geological timescales drives the oxygenation of the atmosphere. Here we quantify natural variations in the burial of organic carbon in deep-sea sediments over the last glacial cycle. Using a new data compilation of hundreds of sediment cores, we show that the accumulation rate of organic carbon in the deep sea was consistently higher (50%) during glacial maxima than during interglacials. The spatial pattern and temporal progression of the changes suggest that enhanced nutrient supply to parts of the surface ocean contributed to the glacial burial pulses, with likely additional contributions from more efficient transfer of organic matter to the deep sea and better preservation of organic matter due to reduced oxygen exposure. These results demonstrate a pronounced climate sensitivity for this global carbon cycle sink. PMID:26923945

  7. Social workers' final act of service: respectful burial arrangements for indigent, unclaimed, and unidentified people.

    PubMed

    Castex, Graciela M

    2007-10-01

    Social workers have long been involved in identifying resources and making final arrangements for clients who die without an estate or have no heirs, who may be institutionalized or unknown to the community, or whose body may be unclaimed for burial. Absent quick intervention, these individuals are often at risk for an anonymous potter's field burial, sometimes in coffins stacked eight deep, with no respectful ceremony of interment. This article provides an overview of societal responses to the need for a final disposition of all people; discusses demographic and social trends that, if realized, may result in a significant increase in indigent burials; and provides information on social work interventions and the identification of resources available for a respectful and dignified final disposition for a client. PMID:18232243

  8. Global pulses of organic carbon burial in deep-sea sediments during glacial maxima

    NASA Astrophysics Data System (ADS)

    Cartapanis, Olivier; Bianchi, Daniele; Jaccard, Samuel L.; Galbraith, Eric D.

    2016-02-01

    The burial of organic carbon in marine sediments removes carbon dioxide from the ocean-atmosphere pool, provides energy to the deep biosphere, and on geological timescales drives the oxygenation of the atmosphere. Here we quantify natural variations in the burial of organic carbon in deep-sea sediments over the last glacial cycle. Using a new data compilation of hundreds of sediment cores, we show that the accumulation rate of organic carbon in the deep sea was consistently higher (50%) during glacial maxima than during interglacials. The spatial pattern and temporal progression of the changes suggest that enhanced nutrient supply to parts of the surface ocean contributed to the glacial burial pulses, with likely additional contributions from more efficient transfer of organic matter to the deep sea and better preservation of organic matter due to reduced oxygen exposure. These results demonstrate a pronounced climate sensitivity for this global carbon cycle sink.

  9. Geohydrology of the unsaturated zone at the burial site for low-level radioactive waste near Beatty, Nye County, Nevada

    USGS Publications Warehouse

    Nichols, W.D.

    1986-01-01

    Low-level radioactive solid waste has been buried in trenches at a site near Beatty, Nevada, since 1962. In 1976, as part of a national program, the U.S. Geological Survey began a study of the geohydrology of the waste burial site to provide a basis for estimating the potential for radionuclide migration in the unsaturated zone beneath the waste burial trenches. Data collected include meteorological information for calibration of a long-term water budget analysis, soil moisture profiles, soil water potentials, and hydraulic properties of representative unsaturated sediment samples to a depth of about 10 m. The waste burial facility is in the northern Amargosa Desert about 170 km northwest of Las Vegas, NV. The region is arid; mean annual precipitation at Lathrop Wells, 30 km south of the site, is only 7.4 cm. The mean daily maximum temperature at Lathrop Wells in July, the hottest month, is 37 C. The site is underlain by poorly stratified deposits of gravelly or silty sand and sandy gravel, and thick beds of clayey sediments. The total thickness of valley fill deposits beneath the site is about 175 m; the unsaturated zone is about 85 m thick. Volumetric soil moisture to depths of 4 m ranges from 4% to 10%, but commonly is in the range from 6% to 8%. Soil water potential, measured to depths of 3 to 10 m, ranged from -10 to -70 bars. Unsaturated hydraulic conductivity computed from laboratory analyses of representative samples ranges from 10 to the -13th power to 10 to the -4th power cm/day. Evaporation studies over a 2-yr period were used to calibrate a numerical procedure for analyzing long-term precipitation data and estimating annual water budgets during the 15-yr period 1962-76. This analysis (1) demonstrated that a potential exists for deep percolation (> 2 m), despite high annual evaporation demands, and (2) provided predictions of the time of yr and the antecedent conditions which enhance the probability of deep percolation. Soil moisture profiles obtained

  10. Influence of aging temperature on the structure and mechanical properties of titanium alloy VT22 subjected to helical rolling

    NASA Astrophysics Data System (ADS)

    Mishin, I. P.; Naydenkin, E. V.; Ratochka, I. V.; Lykova, O. N.; Balushkina, M. A.

    2015-10-01

    The structure and mechanical properties of titanium alloy VT22 after helical rolling and subsequent aging was investigated. It is shown that the treatment leads to the formation of ultra-fine grain/subgrain structure in the alloy. The subsequent aging increases the ultimate strength and yield strength to 1640 and 1590 MPa respectively, while saving satisfactory plasticity (δ > 5%).

  11. Burial dolomitisation in a non-tropical carbonate petroleum reservoir: the Oligocene Tikorangi Formation, Taranaki Basin, New Zealand

    NASA Astrophysics Data System (ADS)

    Hood, Steven D.; Nelson, Campbell S.; Kamp, Peter J. J.

    2004-11-01

    The Oligocene Tikorangi Formation is a subsurface, non-tropical, limestone-rich, fracture-producing oil reservoir in Taranaki Basin, New Zealand. The formation is distinct from uplifted and exposed age-equivalent New Zealand limestones due to partial dolomitisation by modest quantities of silt-sized, scattered, inclusion-rich, euhedral dolomite rhombs, occasionally displaying idiotopic fabrics. Rhombs commonly have dull luminescent Fe-rich cores, and oscillatory bright and dull concentric outers. The dolomites are non-stoichiometric, high calcian and highly ferroan varieties. Dolomite 18O and 13C values are moderately depleted, while associated precursor calcite phases are less depleted. Petrographic, geochemical and geohistory evidence suggest that the dolomite formed during and following the later stages of pressure-dissolution cementation in a relatively closed, moderately deep burial environment (ca. 0.85-1.9 km burial depth, ca. 33-65 °C) in the early Miocene (ca. 24-18 Ma) from warm, saline-enriched pore fluids by mainly mimic fabric-selective replacement of interparticle, and rarely intraparticle, micrite/matrix. Dolomitisation did not affect skeletal grains or calcite cements or develop any secondary porosity. Mg supply was restricted and was likely sourced internally from micritic inter- and intraparticle precursor material, and from the pressure-dissolution of calcitic skeletons. Importantly, dolomitisation occurred prior to compression-related brittle fracturing of the carbonates, responsible for creating extensive hydrocarbon-bearing fracture networks. Because of the greater susceptibility of the dolomitised limestones to brittle fracturing, their location and distribution may have important implications for hydrocarbon prospectivity and production within the Tikorangi Formation.

  12. Recovery of topsoil physicochemical properties in revegetated sites in the sand-burial ecosystems of the Tengger Desert, northern China

    NASA Astrophysics Data System (ADS)

    Li, X. R.; He, M. Z.; Duan, Z. H.; Xiao, H. L.; Jia, X. H.

    2007-08-01

    Recovery in soil properties and processes after sand burial in the Tengger Desert, northern China, was documented at five different-aged revegetated sites (1956, 1964, 1973, 1982, and 1991) and at a reference site with native vegetation, which had never been damaged by sand burial and was enclosed for grazing. The proportions of silt and clay, depth of topsoil and biological soil crusts, and concentrations of soil organic C, K, total N and total P increased with years since revegetation. Most characteristics of topsoil (0-5 cm) characteristics had recovered to 60% of those measured at the reference site by 50 years after sand-binding vegetation had been established. Exceptions were electrical conductivity and contents of sand, silt, CaCO 3 and organic C, which recovered to 20-40% of the values at the reference site. The difference in annual recovery rates of soil properties between the two most recently revegetated sites (0-14 years) was greater than the difference between the two oldest revegetated sites (43-50 years). Best-fit asymptote models showed that the estimated times for the soil properties in the 50-year-old site to reach the same levels as in the reference site (i.e. an undisturbed, native steppified desert ecosystem) would be between 23 and 245 years, but for some properties even maximum recovery after > 50 years still fell significantly short of the level at the reference site. These results suggest that soil recovery is a slow process in an extremely arid desert environment, and therefore the conservation of soil habitat is a crucial issue for land managers.

  13. Germination and emergence of annual species and burial depth: Implications for restoration ecology

    NASA Astrophysics Data System (ADS)

    Limón, Ángeles; Peco, Begoña

    2016-02-01

    Due to the high content of viable seeds, topsoil is usually spread on ground left bare during railway and motorway construction to facilitate the regeneration of vegetation cover. However, during handling of the topsoil, seeds are often buried deeply and they cannot germinate or the seedlings cannot emerge from depth. This study experimentally explores the predictive value of seed mass for seed germination, mortality and seedling emergence at different burial depths for 13 common annual species in semiarid Mediterranean environments. We separate the effect of burial depth on germination and emergence by means of two experiments. In the germination experiment, five replicates of 20 seeds for each species were buried at depths ranging from 0 to 4 cm under greenhouse conditions. Germinated and empty or rotten seeds were counted after 8 weeks. In the emergence experiment, five replicates of four newly-germinated seeds per species were buried at the same depths under controlled conditions and emergence was recorded after 3 weeks. The effect of burial depth on percentage of germination and seedling emergence was dependent on seed size. Although all species showed a decrease in germination with burial depth, this decrease was greater for small-than large-seeded species. Percentage of emergence was positively related to seed mass but negatively related to burial depth. Seed mortality was higher for small-than large-seeded species, but there was no general effect of burial depth on this variable. Thus, the current practice of spreading 30 cm deep layers of topsoil in post-construction restoration projects is unadvisable. In this restoration scenario, thinner layers of topsoil should be used to achieve the maximum potential of the topsoil for germination and seedling establishment.

  14. Phosphorus burial in the ocean over glacial-interglacial time scales

    NASA Astrophysics Data System (ADS)

    Tamburini, F.; Föllmi, K. B.

    2008-12-01

    The role of nutrients and their impact on primary productivity and the fluctuations in atmospheric CO2 over glacial-interglacial periods are intensely debated. One of the cornerstones is the role of phosphorus (P; in the form of phosphate). Suggestions as to the importance of P evolved from an earlier proposal that P actively participated in changing productivity rates and therefore climate change, to the most recent one that changes in the glacial ocean inventory of phosphorus were small and not influential if compared to other macronutrients, such as nitrogen. Using new data coming from a selection of ODP sites, we illustrate oceanic P sedimentary phases distribution and reactive P burial fluxes, and we show how P burial fluxes changed over the last glacial-interglacial period. Concentrations of reactive P are generally lower during glacial times, while mass accumulation rates (MAR) show higher variability. On a global scale, glacial burial fluxes of reactive P are lower than those during interglacial periods by 7-10%, because lack of burial of reactive P on the glacial reduced shelf was apparently not compensated by burial in other regions of the ocean. Using the calculated changes in P burial, we try to infer their possible impact on the phosphate inventory in the world oceans. Using a simple mathematical approach, we find that these changes alone could have increased the phosphate inventory of glacial ocean waters by 20-40% compared to interglacial stages. Variations in the C/P reactive ratios and in the P sedimentary phases distribution at the investigated sites seem to indicate that at the onset of interglacial stages, shallower sites experienced an increase in reactive P concentrations. This seems to point to P-richer waters at glacial terminations, supporting the shelf-nutrient hypothesis and giving phosphorus a role as a potential player in climate change.

  15. Phosphorus burial in the ocean over glacial-interglacial time scales

    NASA Astrophysics Data System (ADS)

    Tamburini, F.; Föllmi, K. B.

    2009-04-01

    The role of nutrients, such as phosphorus (P), and their impact on primary productivity and the fluctuations in atmospheric CO2 over glacial-interglacial periods are intensely debated. Suggestions as to the importance of P evolved from an earlier proposal that P actively participated in changing productivity rates and therefore climate change, to most recent ones that changes in the glacial ocean inventory of phosphorus were important but not influential if compared to other macronutrients, such as nitrate. Using new data coming from a selection of ODP sites, we analyzed the distribution of oceanic P sedimentary phases and calculate reactive P burial fluxes, and we show how P burial fluxes changed over the last glacial-interglacial period at these sites. Concentrations of reactive P are generally lower during glacial times, while mass accumulation rates (MAR) of reactive P show higher variability. If we extrapolate for the analyzed sites, we may assume that in general glacial burial fluxes of reactive P are lower than those during interglacial periods by about 8%, because the lack of burial of reactive P on the glacial shelf reduced in size, was apparently not compensated by burial in other regions of the ocean. Using the calculated changes in P burial, we evaluate their possible impact on the phosphate inventory in the world oceans. Using a simple mathematical approach, we find that these changes alone could have increased the phosphate inventory of glacial ocean waters by 17-40% compared to interglacial stages. Variations in the distribution of sedimentary P phases at the investigated sites seem to indicate that at the onset of interglacial stages, shallower sites experienced an increase in reactive P concentrations, which seems to point to P-richer waters at glacial terminations. All these findings would support the Shelf-Nutrient Hypothesis, which assumes that during glacial low stands nutrients are transferred from shallow sites to deep sea with possible

  16. Intra-crystalline protein diagenesis (IcPD) in Patella vulgata. Part II: Breakdown and temperature sensitivity

    PubMed Central

    Demarchi, B.; Collins, M.J.; Tomiak, P.J.; Davies, B.J.; Penkman, K.E.H.

    2013-01-01

    Artificial diagenesis of the intra-crystalline proteins isolated from Patella vulgata was induced by isothermal heating at 140 °C, 110 °C and 80 °C. Protein breakdown was quantified for multiple amino acids, measuring the extent of peptide bond hydrolysis, amino acid racemisation and decomposition. The patterns of diagenesis are complex; therefore the kinetic parameters of the main reactions were estimated by two different methods: 1) a well-established approach based on fitting mathematical expressions to the experimental data, e.g. first-order rate equations for hydrolysis and power-transformed first-order rate equations for racemisation; and 2) an alternative model-free approach, which was developed by estimating a “scaling” factor for the independent variable (time) which produces the best alignment of the experimental data. This method allows the calculation of the relative reaction rates for the different temperatures of isothermal heating. High-temperature data were compared with the extent of degradation detected in sub-fossil Patella specimens of known age, and we evaluated the ability of kinetic experiments to mimic diagenesis at burial temperature. The results highlighted a difference between patterns of degradation at low and high temperature and therefore we recommend caution for the extrapolation of protein breakdown rates to low burial temperatures for geochronological purposes when relying solely on kinetic data. PMID:23956808

  17. Effects of Burial in Sand and Water Supply Regime on Seedling Emergence of Six Species

    PubMed Central

    ZHENG, YUANRUN; XIE, ZHIXIAO; YU, YI; JIANG, LIANHE; SHIMIZU, HIDEYUKI; RIMMINGTON, GLYN M.

    2005-01-01

    • Background and Aims Air seeding has long been regarded as a quick and successful measure for vegetation rehabilitation in China. However, seedling emergence of often-used species including Agriophyllum squarrosum, Artemisia sphaerocephala, Artemisia ordosica, Hedysarum fruticosum, Caragana korshinskii and Medicago sativa is low. Experiments were conducted under controlled conditions to study the effects of sowing depth and water supply on seedling emergence, in order to understand the requirements for increasing seedling emergence. • Methods Seeds were exposed to different environments of burial and water supply regimes in PVC pots (7 cm in diameter and 11 cm in height) under the same light intensity and alternating temperature regimes in a growth chamber. • Key Results Seedlings of three species (Agriophyllum squarrosum, Artemisia sphaerocephala, Artemisia ordosica) with relatively light seeds emerged well at a 0·5 cm sowing depth under a 7·5 and 10 mm water supply regime. However, few seedlings of these species emerged when the sowing depth was over 1 cm or when water supply was 5 mm. Seedlings of Caragana korshinskii, Hedysarum fruticosum and Medicago sativa emerged from sowing depths of 0·5–4 cm, 0·5–3 cm, and 0·5–4 cm, respectively, under both 7·5 and 10 mm water supply regimes. Under a 5 mm water supply regime, seedlings of these species also emerged at over 1 cm sowing depth. Seeds of all six species sown on the surface of sand did not germinate, and seedlings did not emerge when they were sown at depths greater than 6 cm. • Conclusions Based on these experiments, a 0·5 cm sowing depth resulted in the highest seedling emergence and it is concluded that this is the optimal sowing depth for seedling emergence of all six species. PMID:15820988

  18. Detection of Marked and Unmarked Burial Sites in Louisiana Using Ground Penetrating Radar

    NASA Astrophysics Data System (ADS)

    Smith, M.; Nunn, J. A.

    2008-12-01

    Ground penetrating radar has been used in both north and south Louisiana, to locate marked and unmarked graves. Burials in Oak Ridge, Louisiana, which is in the northern part of the state, were in a church cemetery. Dates of burial ranged from the late 1800s to the present. The survey was conducted to determine the location of empty plots within the cemetery that could be used for future burials and to locate any unmarked burials. Burials in St. Gabriel, Louisiana, which is in the southern portion of the state, consisted of three marked graves on private property. Date of burials occurred in the 1970s. This survey was performed to confirm that the headstones were correctly placed over the bodies. A large surface depression was observed near the presumed location of the graves. Information regarding the exact location of the bodies was not known and one or more bodies were possibly buried in the area beneath the observed large surface depression. A Sensors and Software SmartCart bistatic ground penetrating radar unit equipped with 200-megahertz antennas with 0.5 meters of separation was used at both locations. Penetration was to a sufficient depth in order to determine locations of the burials at both sites. Longer wavelength antennas were available but not used because the 200-megahertz antennas adequately characterized the near subsurface. Sediments in the Oak Ridge site consisted of silty loams and a comparatively deeper depth of penetration was achieved. Sediment in the St. Gabriel site consisted of clays with less depth of penetration than in the Oak Ridge site. Previous studies by others in Baton Rouge, Louisiana just to the north of St. Gabriel have had poor results due to limited depth of penetration except in areas where the soil is covered by concrete or asphalt and thus remains dry year round. Both grave sites were surveyed while the soil was dry in order to ensure maximum depth of penetration. Data interpretation was completed on site during each survey

  19. Sampling and Analysis Instruction for Borehole Sampling at 118-B-1 Burial Ground

    SciTech Connect

    W. S. Thompson

    2007-04-02

    The Washington Closure Hanford (WCH) Field Remediation Project has removed all of the disposed materials and contaminated soil from the 118-B-1 Burial Ground with the exception of tritium-contaminated soil that is believed to extend from the bottom of the present excavation to groundwater and is believed to contribute to tritium contamination observed at down-gradient monitoring Well 199-B8-6. This sampling and analysis instruction (SAI) provides the requirements for sample collection and laboratory analysis for characterization of the vertical distribution of tritium contamination in the vadose zone soil below the 118-B-1 Burial Ground remedial action excavation.

  20. The Sulfur Isotope Composition of the Pyrite Burial Flux in the Modern Ocean

    NASA Astrophysics Data System (ADS)

    Turchyn, A. V.; Antler, G.; Byrne, D. J.; Sun, X.

    2014-12-01

    Microbial sulfate reduction followed by sulfide mineral burial, typically as pyrite, represents the largest removal pathway for sulfur from the exogenic sulfur reservoir. During microbial sulfate reduction, sulfur isotopes are partitioned such that the lighter 32S isotope is preferentially reduced; the magnitude of this partitioning has a large range (0 to 72‰), and therefore the average sulfur isotope composition of the global pyrite burial flux remains enigmatic. Recent work has mapped the global spatial distribution of microbial sulfate reduction rates in the modern ocean, which allows conclusions to be drawn concerning the conditions and controls on where sulfate respiration occurs (Bowles et al., 2014). The local rate of sulfate reduction in a particular sediment column can be calculated by the change in sulfate concentrations in pore fluids below the surface, which yields the net flux of sulfate into marine sediments. A flux of sulfate into the sediment is assumed to be due to diffusion along a concentration gradient set up by the consumption of sulfate at depth. We have calculated the deep-sea rates of microbial sulfate reduction using over 700 drilling sites and arrive at a similar estimate of the global modern rate of sulfate respiration. Rates of sulfate reduction are not, however, the same as the rates of pyrite burial, which is likely limited to the uppermost sediments where reactive iron may be available, or in the most nearshore environments where the terrestrial supply of iron is high and rates of sulfate reduction are orders of magnitude higher than those in the deep-sea. Sulfur isotope fractionation during microbial sulfate reduction is a function of several environmental factors, including the rate of sulfate reduction. We use a new compilation of the link between sulfate reduction rate and sulfur isotope fractionation with a model of pyrite burial in a range of modern marine sediments to derive an estimate of the global pyrite burial flux and

  1. Tillage energy savings from zone burial of shredded and whole cotton stalks

    SciTech Connect

    Carter, L.; Chesson, J.; Thacker, G.; Penner, V.

    1996-04-01

    Two prototypes of a stalk burial implement were tested for energy requirements at the University of California, Shafter Research Station. Both versions of the implement are designed to bury the cotton stalks in a concentrated Zone and reform the bed in the same location. To plow under shredded stalks, both versions of the implement required less energy than a conventional tillage systems typical of the San Joaquin Valley of California. Both stalk burial implements were also used to plow under whole cotton stalks. This offers additional energy savings by eliminating the stalk shredding operation.

  2. New aspects about reduced LCF-life time of spherical ductile cast iron due to dynamic strain aging at intermediate temperatures

    NASA Astrophysics Data System (ADS)

    Mouri, Hayato; Wunderlich, Wilfried; Hayashi, Morihito

    2009-06-01

    Spherical ductile cast iron (FCD400) is widely used as container material in nuclear energy processing line due to its superior mechanical properties and low price. Fatigue properties in low cycle fatigue (LCF) can be described well by the Manson-Coffin-Basquin's rule. However, at intermediate temperature range between 453 and 723 K the elongation-temperature-diagram shows a significantly 20-10% reduced elongation and an increase in yield stress in tensile test experiments. These non-linear deviations and the phenomenon of less ductility at intermediate temperatures are known for a long time [1] [K. Chijiiwa, M. Hayashi, Mechanical properties of ductile cast iron at temperature in the region of room temperature to liquid, Imono 51 (7) (2004) 395-400]. But the following explanation is presented for the first time. In the same temperature range as the reduced fatigue life time dynamic strain ageing (DSA) also known as Portevin-le-Chartelier effect with the formation of visible serrations occurs. Both phenomena are explained by interaction effects between carbon diffusion and dislocation velocity which have at this temperature the same order of magnitude. However, this phenomenon shows interesting behavior at intermediate temperature range. During the low cycle fatigue test, DSA phenomenon disappeared, but mechanical properties show clear evidence of DSA phenomenon. Therefore, the purpose of this paper is to study the correlation of DSA occurrence, LCF and mechanical properties.

  3. Mineralogical, chemical and K-Ar isotopic changes in Kreyenhagen Shale whole rocks and <2 μm clay fractions during natural burial and hydrous-pyrolysis experimental maturation

    NASA Astrophysics Data System (ADS)

    Clauer, N.; Lewan, M. D.; Dolan, M. P.; Chaudhuri, S.; Curtis, J. B.

    2014-04-01

    Progressive maturation of the Eocene Kreyenhagen Shale from the San Joaquin Basin of California was studied by combining mineralogical and chemical analyses with K-Ar dating of whole rocks and <2 μm clay fractions from naturally buried samples and laboratory induced maturation by hydrous pyrolysis of an immature outcrop sample. The K-Ar age decreases from 89.9 ± 3.9 and 72.4 ± 4.2 Ma for the outcrop whole rock and its <2 μm fraction, respectively, to 29.7 ± 1.5 and 21.0 ± 0.7 Ma for the equivalent materials buried to 5167 m. The natural maturation does not produce K-Ar ages in the historical sense, but rather K/Ar ratios of relative K and radiogenic 40Ar amounts resulting from a combined crystallization of authigenic and alteration of initial detrital K-bearing minerals of the rocks. The Al/K ratio of the naturally matured rocks is essentially constant for the entire depth sequence, indicating that there is no detectable variation in the crystallo-chemical organization of the K-bearing alumino-silicates with depth. No supply of K from outside of the rock volumes occurred, which indicates a closed-system behavior for it. Conversely, the content of the total organic carbon (TOC) content decreases significantly with burial, based on the progressive increasing Al/TOC ratio of the whole rocks. The initial varied mineralogy and chemistry of the rocks and their <2 μm fractions resulting from differences in detrital sources and depositional settings give scattered results that homogenize progressively during burial due to increased authigenesis, and concomitant increased alteration of the detrital material. Hydrous pyrolysis was intended to alleviate the problem of mineral and chemical variations in initially deposited rocks of naturally matured sequences. However, experiments on aliquots from thermally immature Kreyenhagen Shale outcrop sample did not mimic the results from naturally buried samples. Experiments conducted for 72 h at temperatures from 270 to 365

  4. The burial of headwater streams in drainage pipes reduces in-stream nitrate retention: results from two US metropolitan areas

    EPA Science Inventory

    Urbanization causes stream degradation in various ways, but perhaps the most extreme example is the burial of streams in underground storm drains to facilitate above ground development or to promote the rapid conveyance of stormwater. Stream burial is extensive in urban basins (...

  5. The burial of headwater streams in drainage pipes reduces in-stream nitrate retention: results from two US metropolitan areas

    EPA Science Inventory

    Nitrogen (N) retention in stream networks is an important ecosystem service that may be affected by the widespread burial of headwater streams in urban watersheds. Stream burial occurs when segments of a channel are encased in drainage pipe and buried beneath the land surface to...

  6. 76 FR 77327 - Allowance for Private Purchase of an Outer Burial Receptacle in Lieu of a Government-Furnished...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-12

    ... AFFAIRS Allowance for Private Purchase of an Outer Burial Receptacle in Lieu of a Government-Furnished.... SUMMARY: Public Law 104-275 was enacted on October 9, 1996. It allows the Department of Veterans Affairs (VA) to provide a monetary allowance towards the private purchase of an outer burial receptacle...

  7. 78 FR 76712 - Allowance for Private Purchase of an Outer Burial Receptacle in Lieu of a Government-Furnished...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-18

    ... AFFAIRS Allowance for Private Purchase of an Outer Burial Receptacle in Lieu of a Government-Furnished.... SUMMARY: Public Law 104-275 was enacted on October 9, 1996. It allows the Department of Veterans Affairs (VA) to provide a monetary allowance towards the private purchase of an outer burial receptacle...

  8. 77 FR 74743 - Allowance for Private Purchase of an Outer Burial Receptacle in Lieu of a Government-Furnished...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-17

    ... AFFAIRS Allowance for Private Purchase of an Outer Burial Receptacle in Lieu of a Government-Furnished.... SUMMARY: Public Law 104-275 was enacted on October 9, 1996. It allows ] the Department of Veterans Affairs (VA) to provide a monetary allowance towards the private purchase of an outer burial receptacle...

  9. 75 FR 67454 - Allowance for Private Purchase of an Outer Burial Receptacle in Lieu of a Government-Furnished...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-02

    ... AFFAIRS Allowance for Private Purchase of an Outer Burial Receptacle in Lieu of a Government-Furnished.... SUMMARY: Public Law 104-275 was enacted on October 9, 1996. It allows the Department of Veterans Affairs (VA) to provide a monetary allowance towards the private purchase of an outer burial receptacle...

  10. 20 CFR 10.412 - Will OWCP pay the costs of burial and transportation of the remains?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Will OWCP pay the costs of burial and transportation of the remains? 10.412 Section 10.412 Employees' Benefits OFFICE OF WORKERS' COMPENSATION PROGRAMS... the costs of burial and transportation of the remains? In a case accepted for death benefits,...

  11. 31 CFR 560.542 - Importation and exportation of human remains for burial, cremation, or interment authorized.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... remains for burial, cremation, or interment authorized. 560.542 Section 560.542 Money and Finance... Statements of Licensing Policy § 560.542 Importation and exportation of human remains for burial, cremation..., cremation, or interment, as well as of coffins or other receptacles containing such human remains, from...

  12. 38 CFR 3.1707 - Plot or interment allowances for burial in a State veterans cemetery or other cemetery.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Plot or interment...: Allowances & Expenses Paid by Va A08se3. § 3.1707 Plot or interment allowances for burial in a State veterans... met. (b) Plot or interment allowance for burial in a State veterans cemetery. VA will pay the plot...

  13. 38 CFR 1.10 - Eligibility for and disposition of the United States flag for burial purposes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Eligibility for and disposition of the United States flag for burial purposes. 1.10 Section 1.10 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS GENERAL PROVISIONS The United States Flag for Burial Purposes § 1.10 Eligibility for and disposition of...

  14. Low-Temperature Aging of Delta-Ferrite in 316L SS Welds; Changes in Mechanical Properties and Etching Properties

    NASA Astrophysics Data System (ADS)

    Abe, Hiroshi; Shimizu, Keita; Watanabe, Yutaka

    Thermal aging embrittlement of LWR components made of stainless cast (e.g. CF-8 and CF-8M) is a potential degradation issue, and careful attention has been paid on it. Although welds of austenitic stainless steels (SSs) have γ-δ duplex microstructure, which is similar to that of the stainless cast, examination on thermal aging characteristics of the SS welds is very limited. In order to evaluate thermal aging behavior of weld metal of austenitic stainless steel, the 316L SS weld metal has been prepared and changes in mechanical properties and in etching properties at isothermal aging at 335°C have been investigated. The hardness of the ferrite phase has increased with aging, while the hardness of austenite phase has stayed same. It has been suggested that spinodal decomposition has occurred in δ-ferrite by the 335°C aging. The etching rates of δ-ferrite at immersion test in 5wt% hydrochloric acid solution have been also investigated using an AFM technique. The etching rate of ferrite phase has decreased consistently with the increase in hardness of ferrite phase. It has been thought that this characteristic is also caused by spinodal decomposition of ferrite into chromium-rich (α') and iron-rich (α).

  15. Phanerozoic burial and exhumation history of southernmost Norway estimated from apatite fission-track analysis data and geological observations

    NASA Astrophysics Data System (ADS)

    Japsen, Peter; Green, Paul F.; Bonow, Johan M.; Chalmers, James A.; Rasmussen, Erik S.

    2016-04-01

    fourth event that is not detected by the AFTA data. Fossen, Mangerud, Hesthammer, Bugge, Gabrielsen 1997: The Bjorøy Formation: a newly discovered occurrence of Jurassic sediments in the Bergen Arc System. Norsk Geologisk Tidsskrift 77. Fredin, Zwingmann, Knies, Sørlie, Gandal, Lie, Müller, Vogt, 2014: Saprolites on- and offshore Norway: New constraints on formation processes and age. Nordic Geological Winter Meeting, Lund, Sweden. Japsen, Green, Bonow, Erlström 2015: Episodic burial and exhumation of the southern Baltic Shield: Epeirogenic uplifts during and after break-up of Pangea. Gondwana Research, in press. Lidmar-Bergström, Bonow, Japsen 2013: Stratigraphic landscape analysis and geomorphological paradigms: Scandinavia as an example of Phanerozoic uplift and subsidence. Global and Planetary Change 100. Rohrman, van der Beek, Andriessen, Cloetingh 1995: Meso-Cenozoic morphotectonic evolution of southern Norway: Neogene domal uplift inferred from apatite fission track thermochronology. Tectonics 14.

  16. STEM/AEM evidence for preservation of burial diagenetic fabrics in Devonian shales: Implications for fluid/rock interaction in cratonic basins (U.S.A.)

    SciTech Connect

    Hover, V.C.; Peacor, D.R.; Walter, L.M.

    1996-05-01

    Fabrics, microstructures, and compositions of authigenic illite-rich clays in Devonian intracratonic basin shales were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), and scanning transmission electron/analytical electron microscopy (STEM/AEM) methods in order to relate the extent of clay diagenesis to the timing of mudstone-system closure and to reconcile conflicting radiogenic and paleomagnetic ages obtained from these shales and associated limestones and bentonites. Authigenic illite in these Devonian shales is similar to post-transition illite-rich mixed-layer illite/smectite (I/S) in Gulf Coast and other young basin mudstones that have formed through replacement of detrital smectite or smectite-rich I/S without subsequent diagenetic modification. Preservation of burial diagenetic, authigenic, mixed-layer I/S microstructures in these Devonian shales implies that they have remained effectively closed systems following the smectite-to-illite transformation. Later Alleghenian (ca. 300 Ma) tectonic or fluid-flow events recorded by authigenic minerals in bentonites and carbonate lithologies throughout the US. Midcontinent are apparently not recorded in these Devonian shales. Preservation of diagenetic fabrics indicates that radiogenic isotope dating of cratonic basin shales should yield syndepositional to early burial diagenetic ages corresponding to the timing of I/S authigenesis.

  17. Geohydrology of the unsaturated zone at the burial site for low-level radioactive waste near Beatty, Nye County, Nevada

    USGS Publications Warehouse

    Nichols, William D.

    1987-01-01

    Low-level radioactive solid waste has been buried in trenches at a site near Beatty, Nev., since 1962. In 1976, as part of a national program, the U.S. Geological Survey began a study of the geohydrology of the waste-burial site to provide a basis for estimating the potential for radionuclide migration in the unsaturated zone beneath the waste-burial trenches. Data collected include meteorological information for calibration of a long-term water-budget analysis, soil-moisture profiles, soil-water potentials, and hydraulic properties of representative unsaturated sediment samples to a depth of about 10 meters (m). The waste-burial facility is in the northern Amargosa Desert about 170 kilometers (km) northwest of Las Vegas, Nevo The region is arid; mean annual precipitation at Lathrop Wells, 30 km south of the site, is only 7.4 centimeters (cm). The mean daily maximum temperature at Lathrop Wells in July, the hottest month, is 37 ?C. The site is underlain by poorly stratified deposits of gravelly or silty sand and sandy gravel, and thick beds of clayey sediments. The total thickness of valley-fill deposits beneath the site is about 175 m; the unsaturated zone is about 85 m thick. Volumetric soil moisture to depths of 4 m ranges from 4 to 10 percent but commonly is in the range of 6 to 8 percent. Soil-water potential, measured to depths of 3 to 10 m, ranged from -10 to -70 bars. Unsaturated hydraulic conductivity computed from laboratory analyses of representative samples ranges from 10 -13 to 10 -14 centimeters per day (cm/d). Evaporation studies over a 2-year (yr) period were used to calibrate a numerical procedure for analyzing long-term precipitation data and estimating annual water budgets during the 15-yr period 1962-76. This analysis (1) demonstrated that a potential exists for deep percolation (greater than 2 m), despite high annual evaporation demands, and (2) provided predictions of the time of year and the antecedent conditions that enhance the probability

  18. Aging gauge

    DOEpatents

    Betts, Robert E.; Crawford, John F.

    1989-04-04

    An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.

  19. Aging gauge

    DOEpatents

    Betts, Robert E.; Crawford, John F.

    1989-01-01

    An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.

  20. Identification of leachate from livestock mortality burial using electrical resistivity and small-loop EM survey: case history

    NASA Astrophysics Data System (ADS)

    Song, Sung-Ho; Cho, In-Ky; Choi, Kwang-Jun

    2015-01-01

    Leachate from livestock mortality burial is harmful to the soil and groundwater environment and adequate assessment approaches are necessary to manage burial sites. Among the methods used to detect leachate, geophysical surveys, including electrical resistivity and electromagnetic (EM) techniques, are used in many engineering approaches to environmental problems, such as identifying contaminant plumes and evaluating hydrogeological conditions. Electrical resistivity, with a small-loop EM survey, was used in this study as a reconnaissance technique to identify the burial shape and distribution of leachate from livestock mortality burial in five small separate zones. We conducted a multi-frequency small-loop EM survey using lattice nets and acquired apparent conductivity values along several parallel and perpendicular lines over a burial site. We also compared geophysical results to the geochemical analysis of samples from both a leachate collection well and a downstream observation well within the study area. Depth slices of apparent conductivities at each frequency (obtained from the small-loop EM survey data) clearly identified the subsurface structure of the burial shape and the extent of leachate transport. Low-resistivity zones, identified from two-dimensional (2D) electrical resistivity imaging results, were matched to the five burial zones (within a depth of 5 m), as well as high electrical conductivity of the leachate obtained from leachate collection wells, and depth slices of the apparent conductivity distribution obtained from the small-loop EM survey. A three-dimensional (3D) inversion of resistivity data provided a detailed 3D structure of the overall burial site and leachate pathways. Moreover, these zones were widely spread over the burial site, indicating that leachate potentially extended through damaged regions of the composite liner to a depth of 10 m along the downstream groundwater flow. Both the small-loop EM method and the electrical

  1. WINTER FLOUNDER PSUEDOPLEURONECTES AMERICANUS HATCHING SUCCESS AS A FUNCTION OF BURIAL DEPTH IN THE LABORATORY

    EPA Science Inventory

    Previous experiments have shown that viable hatch of winter flounder eggs is reduced when the eggs are buried by as little as one half of one egg diameter (approximately 0.5 mm of sediment). This sensitivity to burial has resulted in seasonal banning of dredging in several north...

  2. 77 FR 35755 - Agency Information Collection (Application for Burial Benefits) Activities Under OMB Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-14

    ... AFFAIRS Agency Information Collection (Application for Burial Benefits) Activities Under OMB Review AGENCY... abstracted below to the Office of Management and Budget (OMB) for review and comment. The PRA submission... Benefits (Under 38 U.S.C. Chapter 23), VA Form 21-530. OMB Control Number: 2900-0003. Type of...

  3. Cleanup Verification Package for the 118-B-6, 108-B Solid Waste Burial Ground

    SciTech Connect

    M. L. Proctor

    2006-06-13

    This cleanup verification package documents completion of remedial action for the 118-B-6, 108-B Solid Waste Burial Ground. The 118-B-6 site consisted of 2 concrete pipes buried vertically in the ground and capped by a concrete pad with steel lids. The site was used for the disposal of wastes from the "metal line" of the P-10 Tritium Separation Project.

  4. Mixed Waste Management Facility (MWMF) Old Burial Ground (OBG) source control technology and inventory study

    SciTech Connect

    Flach, G.P.; Rehder, T.E.; Kanzleiter, J.P.

    1996-10-02

    This report has been developed to support information needs for wastes buried in the Burial Ground Complex. Information discussed is presented in a total of four individual attachments. The general focus of this report is to collect information on estimated source inventories, leaching studies, source control technologies, and to provide information on modeling parameters and associated data deficiencies.

  5. Geologic Descriptions for the Solid-Waste Low Level Burial Grounds

    SciTech Connect

    Bjornstad, Bruce N.; Lanigan, David C.

    2007-09-23

    This document provides the stratigraphic framework and six hydrogeologic cross sections and interpretations for the solid-waste Low Level Burial Grounds on the Hanford Site. Four of the new cross sections are located in the 200 West Area while the other two are located within the 200 East Area. The cross sections display sediments of the vadose zone and uppermost unconfined aquifer.

  6. Social Workers' Final Act of Service: Respectful Burial Arrangements for Indigent, Unclaimed, and Unidentified People

    ERIC Educational Resources Information Center

    Castex, Graciela M.

    2007-01-01

    Social workers have long been involved in identifying resources and making final arrangements for clients who die without an estate or have no heirs, who may be institutionalized or unknown to the community, or whose body may be unclaimed for burial. Absent quick intervention, these individuals are often at risk for an anonymous potter's field…

  7. Passive Neutron Non-Destructive Assay for Remediation of Radiological Waste at Hanford Burial Grounds- 13189

    SciTech Connect

    Simpson, A.; Pitts, M.; Ludowise, J.D.; Valentinelli, P.; Grando, C.J.; Haggard, D.L.

    2013-07-01

    The Hanford burial grounds contains a broad spectrum of low activity radioactive wastes, transuranic (TRU) wastes, and hazardous wastes including fission products, byproduct material (thorium and uranium), plutonium and laboratory chemicals. A passive neutron non-destructive assay technique has been developed for characterization of shielded concreted drums exhumed from the burial grounds. This method facilitates the separation of low activity radiological waste containers from TRU waste containers exhumed from the burial grounds. Two identical total neutron counting systems have been deployed, each consisting of He-3 detectors surrounded by a polyethylene moderator. The counts are processed through a statistical filter that removes outliers in order to suppress cosmic spallation events and electronic noise. Upon completion of processing, a 'GO / NO GO' signal is provided to the operator based on a threshold level equivalent to 0.5 grams of weapons grade plutonium in the container being evaluated. This approach allows instantaneous decisions to be made on how to proceed with the waste. The counting systems have been set up using initial on-site measurements (neutron emitting standards loaded into surrogate waste containers) combined with Monte Carlo modeling techniques. The benefit of this approach is to allow the systems to extend their measurement ranges, in terms of applicable matrix types and container sizes, with minimal interruption to the operations at the burial grounds. (authors)

  8. Preliminary fire hazard analysis for the PUTDR and TRU trenches in the Solid Waste Burial Ground

    SciTech Connect

    Gaschott, L.J.

    1995-06-16

    This document represents the Preliminary Fire Hazards Analysis for the Pilot Unvented TRU Drum Retrieval effort and for the Transuranic drum trenches in the low level burial grounds. The FHA was developed in accordance with DOE Order 5480.7A to address major hazards inherent in the facility.

  9. 32 CFR 553.15 - Persons eligible for burial in Arlington National Cemetery.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... individual concerned was disabled or died from a disease or injury incurred or aggravated in line of duty... collusion. (2) An unmarried adult child may be interred in the same grave in which the parent has been or... a group burial may be interred in the same cemetery but not in the same grave. (i) The...

  10. 32 CFR 553.15 - Persons eligible for burial in Arlington National Cemetery.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... individual concerned was disabled or died from a disease or injury incurred or aggravated in line of duty... collusion. (2) An unmarried adult child may be interred in the same grave in which the parent has been or... a group burial may be interred in the same cemetery but not in the same grave. (i) The...

  11. 618-10 Burial Ground VPU Nonintrusive Characterization Process and Data Collection Workshop

    SciTech Connect

    S. Khabir

    2010-12-21

    This report presents the nonintrusive characterization measurement results for the 618-10 Burial Ground and provides a general assessment of the estimated dose, isotopic concentrations, and bounding transuranic radionuclide inventories for the 618-10 vertical pipe units and trenches, based on interpretation of data from a system of in situ radiological multi-detector probes.

  12. Palmer amaranth seed mortality in response to burial depth and time

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glyphosate resistant Palmer amaranth infests millions of arable acres in the SE US. One proposed method of reducing population numbers is to bury surface seeds deeply, below their optimal emergence zone. The objective of this study was to determine how burial longevity and depth impact Palmer amaran...

  13. Draft Genome Sequence of an Oceanobacillus sp. Strain Isolated from Soil in a Burial Crypt

    PubMed Central

    Arizaga, Ylenia; Bikandi, Joseba; Garaizar, Javier; Ganau, Giulia; Paglietti, Bianca; Deligios, Massimo; Rubino, Salvatore

    2016-01-01

    We present the draft genome of an Oceanobacillus sp. strain isolated from spores found in soil samples from a burial crypt of the Cathedral of Sant'Antonio Abate in Castelsardo, Italy. The data obtained indicated the closest relation of the strain with Oceanobacillus caeni. PMID:27469952

  14. 38 CFR 3.1702 - Persons who may receive burial benefits; priority of payments.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... VA may grant additional burial benefits, including the plot or interment allowance, reimbursement for... an agency or political subdivision of a State, files under § 3.1707, Plot or interment allowance for... for the plot or interment allowance (except for claims filed by a State or an agency or...

  15. Hydrogeologic investigation of the Maxey Flats radioactive waste burial site, Fleming County, Kentucky

    USGS Publications Warehouse

    Zehner, H.H.

    1983-01-01

    Burial trenches at the Maxey Flats radioactive waste burial site cover an area of about 20 acres, and are located on a plateau, about 300 to 400 feet above surrounding valleys. All waste is buried in the Nancy Member of the Borden Formation, and most is in the weathered shale (regolith) part of this member. Recharge to the rocks is probably by infiltration of rainfall through regolith at the top of the hill. At least two water tables are present: near the base of the regolith, at a depth of about 25 feet and; in the Ohio Shale, at a depth of about 300 feet. About 95 percent of ground-water discharge to streams is from colluvium on hillsides and valley alluvium. The remaining 5 percent is discharge from bedrock, of which about 0.5 percent is from rocks underlying the burial area. Waste radionuclides in the subsurface, other than tritium, were observed only in the regolith of the Nancy Member. Only tritium was observed with certainty in deeper rocks and in the adjacent valley alluvium. Other waste radionuclides were in streamwater and stream sediment, and may have been transported with overland runoff from the surface of the burial site. (USGS)

  16. The Influence of Ni and V Trace Elements on High-Temperature Tensile Properties and Aging of A356 Aluminum Foundry Alloy

    NASA Astrophysics Data System (ADS)

    di Giovanni, Maria Teresa; Cerri, Emanuela; Casari, Daniele; Merlin, Mattia; Arnberg, Lars; Garagnani, Gian Luca

    2016-05-01

    High-temperature tensile properties of unmodified A356 alloy with and without the addition of Ni or V in traces (600 and 1000 ppm of Ni and V, respectively) were investigated by analyzing samples obtained from sand and permanent mold castings in the as-cast and T6 heat-treated conditions. Tensile tests were performed at 508 K (235 °C) at a crosshead speed of 1 mm/min. In addition, samples were subjected to artificial aging at 508 K (235 °C) for different times, and corresponding hardness curves were plotted. Microstructures and fracture surfaces, analyzed by FEG-SEM equipped with energy dispersive X-ray spectroscopy, showed that neither Ni nor V addition had a detrimental effect on high-temperature tensile properties. Aging curves showed a strong loss of hardness affecting the T6 class between 30-min and 1-h exposure time. After 6-h aging, no evidence of aging treatment persisted on hardness of the tested material. Hardness values did not reveal any significant difference between the reference alloy and the Ni- and V-containing alloys in both casting conditions, in complete analogy with the tensile properties. Unmodified eutectic silicon particles provided inhomogeneity in the α-Al matrix and acted as the principal source of stress concentration leading to fracture.

  17. Limits on the Abundance and Burial Depth of Lunar Polar Ice

    NASA Technical Reports Server (NTRS)

    Elphic, Richard C.; Paige, David A.; Siegler, Matthew A.; Vasavada, Ashwin R.; Teodoro, Luis A.; Eke, Vincent R.

    2012-01-01

    The Diviner imaging radiometer experiment aboard the Lunar Reconnaissance Orbiter has revealed that surface temperatures in parts of the lunar polar regions are among the lowest in the solar system. Moreover, modeling of these Diviner data using realistic thermal conductivity profiles for lunar regolith and topography-based illumination has been done, with surprising results. Large expanses of circum-polar terrain appear to have near-subsurface temperatures well below 110K, despite receiving episodic low-angle solar illumination [Paige et al., 2010]. These subsurface cold traps could provide areally extensive reservoirs of volatiles. Here we examine the limits to abundance and burial depth of putative volatiles, based on the signature they would create for orbital thermal and epithermal neutrons. Epithermals alone are not sufficient to break the abundance-depth ambiguity, while thermal neutrons provide an independent constraint on the problem. The subsurface cold traps are so large that even modest abundances, well below that inferred from LCROSS observations, would produce readily detectable signatures in the Lunar Prospector neutron spectrometer data [Colaprete et al., 2010]. Specifically, we forward-model the thermal and epithermal neutron leakage flux that would be observed for various ice concentrations, given the depth at which ice stability begins. The LCROSS results point to a water-equivalent hydrogen abundance (WEH) in excess of 10 wt%, when all hydrogenous species are added together (except for H2, detected by LAMP on LRO [Gladstone et al., 2010]). When such an ice abundance is placed in a layer below the stability depth of Paige et al., the epithermal and thermal neutron leakage fluxes are vastly reduced and very much at odds with orbital observations. So clearly an environment that is conducive to cold trapping is necessary but not sufficient for the presence of volatiles such as water. We present the limits on the abundances that are indeed consistent

  18. Limits on the Abundance and Burial Depth of Lunar Polar Ice

    NASA Astrophysics Data System (ADS)

    Elphic, R. C.; Paige, D. A.; Siegler, M. A.; Vasavada, A. R.; Teodoro, L. A.; Eke, V. R.

    2011-12-01

    The Diviner imaging radiometer experiment aboard the Lunar Reconnaissance Orbiter has revealed that surface temperatures in parts of the lunar polar regions are among the lowest in the solar system. Moreover, modeling of these Diviner data using realistic thermal conductivity profiles for lunar regolith and topography-based illumination has been done, with surprising results. Large expanses of circum-polar terrain appear to have near-subsurface temperatures well below 110K, despite receiving episodic low-angle solar illumination [Paige et al., 2010]. These subsurface cold traps could provide areally extensive reservoirs of volatiles. Here we examine the limits to abundance and burial depth of putative volatiles, based on the signature they would create for orbital thermal and epithermal neutrons. Epithermals alone are not sufficient to break the abundance-depth ambiguity, while thermal neutrons provide an independent constraint on the problem. The subsurface cold traps are so large that even modest abundances, well below that inferred from LCROSS observations, would produce readily detectable signatures in the Lunar Prospector neutron spectrometer data [Colaprete et al., 2010]. Specifically, we forward-model the thermal and epithermal neutron leakage flux that would be observed for various ice concentrations, given the depth at which ice stability begins. The LCROSS results point to a water-equivalent hydrogen abundance (WEH) in excess of 10 wt%, when all hydrogenous species are added together (except for H2, detected by LAMP on LRO [Gladstone et al., 2010]). When such an ice abundance is placed in a layer below the stability depth of Paige et al., the epithermal and thermal neutron leakage fluxes are vastly reduced and very much at odds with orbital observations. So clearly an environment that is conducive to cold trapping is necessary but not sufficient for the presence of volatiles such as water. We present the limits on the abundances that are indeed consistent

  19. Organic carbon burial rates in mangrove sediments: strengthening the global budget

    USGS Publications Warehouse

    Breithaupt, J.; Smoak, Joseph M.; Smith, Thomas J., III; Sanders, Christian J.; Hoare, Armando

    2012-01-01

    Mangrove wetlands exist in the transition zone between terrestrial and marine environments and as such were historically overlooked in discussions of terrestrial and marine carbon cycling. In recent decades, mangroves have increasingly been credited with producing and burying large quantities of organic carbon (OC). The amount of available data regarding OC burial in mangrove soils has more than doubled since the last primary literature review (2003). This includes data from some of the largest, most developed mangrove forests in the world, providing an opportunity to strengthen the global estimate. First-time representation is now included for mangroves in Brazil, Colombia, Malaysia, Indonesia, China, Japan, Vietnam, and Thailand, along with additional data from Mexico and the United States. Our objective is to recalculate the centennial-scale burial rate of OC at both the local and global scales. Quantification of this rate enables better understanding of the current carbon sink capacity of mangroves as well as helps to quantify and/or validate the other aspects of the mangrove carbon budget such as import, export, and remineralization. Statistical analysis of the data supports use of the geometric mean as the most reliable central tendency measurement. Our estimate is that mangrove systems bury 163 (+40; -31) g OC m-2 yr-1 (95% C.I.). Globally, the 95% confidence interval for the annual burial rate is 26.1 (+6.3; -5.1) Tg OC. This equates to a burial fraction that is 42% larger than that of the most recent mangrove carbon budget (2008), and represents 10–15% of estimated annual mangrove production. This global rate supports previous conclusions that, on a centennial time scale, 8–15% of all OC burial in marine settings occurs in mangrove systems.

  20. Nationwide Surveillance for Pathogenic Microorganisms in Groundwater near Carcass Burials Constructed in South Korea in 2010

    PubMed Central

    Joung, Ha Kyung; Han, Sang Ha; Park, Su-Jung; Jheong, Weon-Hwa; Ahn, Tae Seok; Lee, Joong-Bok; Jeong, Yong-Seok; Jang, Kyung Lib; Lee, Gyu-Cheol; Rhee, Ok-Jae; Park, Jeong-Woong; Paik, Soon Young

    2013-01-01

    Widespread outbreaks of foot-and-mouth disease and avian influenza occurred in South Korea during 2010. In response to the culling of many animals to attenuate the spread of disease, South Korea used mass burial sites to dispose of the large number of carcasses; consequently, concerns about groundwater contamination by leachate from these burial sites are increasing. Groundwater is one of the main sources of drinking water, and its cleanliness is directly related to public health. Thus, this study aimed to evaluate the safety of groundwater around the burial sites (total of 600 sites). A total of 1,200 groundwater samples were collected though the country, and microbial analysis was conducted during two time periods: during the spring (n = 600; April to June 2012) and after rainfall (n = 600; August to October, 2012; fall). Fecal coliform and Escherichia coli were detected in 173 (14.4%) and 85 (7.1%) of the 1,200 samples, respectively. Salmonella spp. and Shigella spp. each were detected only once (0.083%). Clostridium perfringens was detected from 7 groundwater samples (0.583%), and E. coli O157:H7 was not detected. With respect to norovirus, only the GII type was detected from six groundwater samples (0.5%), and enterovirus was detected in 15 groundwater samples (1.25%). The frequency of E. coli that we detected was lower than that found in previous studies conducted in South Korea, but we detected higher frequency of fecal coliform than that observed in a previous report. The contamination frequencies of Salmonella spp. and Shigella spp. were very low, but C. perfringens, which could be an indicator of fecal pollution, was detected in seven regions. Overall, the results of the present study indicate a low possibility of contamination from burial sites. However, consistent monitoring is required to prevent microbial contamination of groundwater near the burial sites. PMID:24351737