Science.gov

Sample records for air temperatures ranging

  1. Thermodynamic and Transport Properties of Real Air Plasma in Wide Range of Temperature and Pressure

    NASA Astrophysics Data System (ADS)

    Wang, Chunlin; Wu, Yi; Chen, Zhexin; Yang, Fei; Feng, Ying; Rong, Mingzhe; Zhang, Hantian

    2016-07-01

    Air plasma has been widely applied in industrial manufacture. In this paper, both dry and humid air plasmas' thermodynamic and transport properties are calculated in temperature 300-100000 K and pressure 0.1-100 atm. To build a more precise model of real air plasma, over 70 species are considered for composition. Two different methods, the Gibbs free energy minimization method and the mass action law method, are used to determinate the composition of the air plasma in a different temperature range. For the transport coefficients, the simplified Chapman-Enskog method developed by Devoto has been applied using the most recent collision integrals. It is found that the presence of CO2 has almost no effect on the properties of air plasma. The influence of H2O can be ignored except in low pressure air plasma, in which the saturated vapor pressure is relatively high. The results will serve as credible inputs for computational simulation of air plasma. supported by the National Key Basic Research Program of China (973 Program)(No. 2015CB251002), National Natural Science Foundation of China (Nos. 51521065, 51577145), the Science and Technology Project Funds of the Grid State Corporation (SGTYHT/13-JS-177), the Fundamental Research Funds for the Central Universities, and State Grid Corporation Project (GY71-14-004)

  2. Equatorial range limits of an intertidal ectotherm are more linked to water than air temperature.

    PubMed

    Seabra, Rui; Wethey, David S; Santos, António M; Gomes, Filipa; Lima, Fernando P

    2016-10-01

    As climate change is expected to impose increasing thermal stress on intertidal organisms, understanding the mechanisms by which body temperatures translate into major biogeographic patterns is of paramount importance. We exposed individuals of the limpet Patella vulgata Linnaeus, 1758, to realistic experimental treatments aimed at disentangling the contribution of water and air temperature for the buildup of thermal stress. Treatments were designed based on temperature data collected at the microhabitat level, from 15 shores along the Atlantic European coast spanning nearly 20° of latitude. Cardiac activity data indicated that thermal stress levels in P. vulgata are directly linked to elevated water temperature, while high air temperature is only stressful if water temperature is also high. In addition, the analysis of the link between population densities and thermal regimes at the studied locations suggests that the occurrence of elevated water temperature may represent a threshold P. vulgata is unable to tolerate. By combining projected temperatures with the temperature threshold identified, we show that climate change will likely result in the westward expansion of the historical distribution gap in the Bay of Biscay (southwest France), and northward contraction of the southern range limit in south Portugal. These findings suggest that even a minor relaxing of the upwelling off northwest Iberia could lead to a dramatic increase in thermal stress, with major consequences for the structure and functioning of the intertidal communities along Iberian rocky shores.

  3. Optical Measurement of the Speed of Sound in Air Over the Temperature Range 300-650 K

    NASA Technical Reports Server (NTRS)

    Hart, Roger C.; Balla, R. Jeffrey; Herring, G. C.

    2000-01-01

    Using laser-induced thermal acoustics (LITA), the speed of sound in room air (1 atm) is measured over the temperature range 300-650 K. Since the LITA apparatus maintains a fixed sound wavelength as temperature is varied, this temperature range simultaneously corresponds to a sound frequency range of 10-15 MHz. The data are compared to a published model and typically agree within 0.1%-0.4% at each of 21 temperatures.

  4. Physical activity profile of 2014 FIFA World Cup players, with regard to different ranges of air temperature and relative humidity

    NASA Astrophysics Data System (ADS)

    Chmura, Paweł; Konefał, Marek; Andrzejewski, Marcin; Kosowski, Jakub; Rokita, Andrzej; Chmura, Jan

    2016-09-01

    The present study attempts to assess changes in soccer players' physical activity profiles under the simultaneous influence of the different combinations of ambient temperature and relative humidity characterising matches of the 2014 FIFA World Cup hosted by Brazil. The study material consisted of observations of 340 players representing 32 national teams taking part in the tournament. The measured indices included total distances covered; distances covered with low, moderate, or high intensity; numbers of sprints performed, and peak running speeds achieved. The analysis was carried out using FIFA official match data from the Castrol Performance Index system. Ultimately, consideration was given to a combination of three air temperature ranges, i.e. below 22 °C, 22-28 °C, and above 28 °C; and two relative humidity ranges below 60 % and above 60 %. The greatest average distance recorded (10.54 ± 0.91 km) covered by players at an air temperature below 22 °C and a relative humidity below 60 %, while the shortest (9.83 ± 1.08 km) characterised the same air temperature range, but conditions of relative humidity above 60 % (p ≤ 0.001). Two-way ANOVA revealed significant differences (p ≤ 0.001) in numbers of sprints performed by players, depending on whether the air temperature range was below 22 °C (40.48 ± 11.17) or above 28 °C (30.72 ± 9.40), but only where the relative humidity was at the same time below 60 %. Results presented indicate that the conditions most comfortable for physical activity on the part of players occur at 22 °C, and with relative humidity under 60 %.

  5. Physical activity profile of 2014 FIFA World Cup players, with regard to different ranges of air temperature and relative humidity.

    PubMed

    Chmura, Paweł; Konefał, Marek; Andrzejewski, Marcin; Kosowski, Jakub; Rokita, Andrzej; Chmura, Jan

    2017-04-01

    The present study attempts to assess changes in soccer players' physical activity profiles under the simultaneous influence of the different combinations of ambient temperature and relative humidity characterising matches of the 2014 FIFA World Cup hosted by Brazil. The study material consisted of observations of 340 players representing 32 national teams taking part in the tournament. The measured indices included total distances covered; distances covered with low, moderate, or high intensity; numbers of sprints performed, and peak running speeds achieved. The analysis was carried out using FIFA official match data from the Castrol Performance Index system. Ultimately, consideration was given to a combination of three air temperature ranges, i.e. below 22 °C, 22-28 °C, and above 28 °C; and two relative humidity ranges below 60 % and above 60 %. The greatest average distance recorded (10.54 ± 0.91 km) covered by players at an air temperature below 22 °C and a relative humidity below 60 %, while the shortest (9.83 ± 1.08 km) characterised the same air temperature range, but conditions of relative humidity above 60 % (p ≤ 0.001). Two-way ANOVA revealed significant differences (p ≤ 0.001) in numbers of sprints performed by players, depending on whether the air temperature range was below 22 °C (40.48 ± 11.17) or above 28 °C (30.72 ± 9.40), but only where the relative humidity was at the same time below 60 %. Results presented indicate that the conditions most comfortable for physical activity on the part of players occur at 22 °C, and with relative humidity under 60 %.

  6. Oxidation characteristics of Beta-21S in air in the temperature range 600 to 800 C

    NASA Technical Reports Server (NTRS)

    Wallace, Terryl A.; Clark, Ronald K.; Wiedemann, Karl E.

    1992-01-01

    The metastable beta-Ti alloy Beta-21S, Ti-15Mo-2.7Nb-3Al-0.2Si (weight percent), has been proposed as a candidate for use in metal matrix composites in future hypersonic vehicles. The present study investigated the oxidation behavior of Beta-21S over the temperature range 600 C to 800 C. Oxidation weight gain was evaluated using thermogravimetric analysis. Oxidized specimens were evaluated using x ray diffraction techniques, scanning electron microscopy, energy dispersive x ray analysis, and electron microprobe analysis to identify oxidation products and evaluate oxidation damage to the alloy.

  7. Long-Range Forecasting of Surface Air Temperature and Precipitation for the Korean Peninsula

    DTIC Science & Technology

    2013-03-01

    Murphree David Meyer THIS PAGE INTENTIONALLY LEFT BLANK i REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704–0188 Public reporting burden for this...ABSTRACT Unclassified 20. LIMITATION OF ABSTRACT UU NSN 7540–01–280–5500 Standard Form 298 (Rev. 2–89) Prescribed by ANSI Std. 239–18 ii THIS...the Heidke Skill Scores ( HSS ) at a 1.5 month lead for Jan–Mar temperature forecasts. In this example, the HSS for the Korean region is between 0.0

  8. Impact of Solar Control PVB Glass on Vehicle Interior Temperatures, Air-Conditioning Capacity, Fuel Consumption, and Vehicle Range

    SciTech Connect

    Rugh, J.; Chaney, L.; Venson, T.; Ramroth, L.; Rose, M.

    2013-04-01

    The objective of the study was to assess the impact of Saflex1 S-series Solar Control PVB (polyvinyl butyral) configurations on conventional vehicle fuel economy and electric vehicle (EV) range. The approach included outdoor vehicle thermal soak testing, RadTherm cool-down analysis, and vehicle simulations. Thermal soak tests were conducted at the National Renewable Energy Laboratory's Vehicle Testing and Integration Facility in Golden, Colorado. The test results quantified interior temperature reductions and were used to generate initial conditions for the RadTherm cool-down analysis. The RadTherm model determined the potential reduction in air-conditioning (A/C) capacity, which was used to calculate the A/C load for the vehicle simulations. The vehicle simulation tool identified the potential reduction in fuel consumption or improvement in EV range between a baseline and modified configurations for the city and highway drive cycles. The thermal analysis determined a potential 4.0% reduction in A/C power for the Saflex Solar PVB solar control configuration. The reduction in A/C power improved the vehicle range of EVs and fuel economy of conventional vehicles and plug-in hybrid electric vehicles.

  9. Long-term patterns of air temperatures, daily temperature range, precipitation, grass-reference evapotranspiration and aridity index in the USA Great Plains: Part I. Spatial trends

    NASA Astrophysics Data System (ADS)

    Kukal, M.; Irmak, S.

    2016-11-01

    Due to their substantial spatio-temporal behavior, long-term quantification and analyses of important hydrological variables are essential for practical applications in water resources planning, evaluating the water use of agricultural crop production and quantifying crop evapotranspiration patterns and irrigation management vs. hydrologic balance relationships. Observed data at over 800 sites across the Great Plains of USA, comprising of 9 states and 2,307,410 km2 of surface area, which is about 30% of the terrestrial area of the USA, were used to quantify and map large-scale and long-term (1968-2013) spatial trends of air temperatures, daily temperature range (DTR), precipitation, grass-reference evapotranspiration (ETo) and aridity index (AI) at monthly, growing season and annual time steps. Air temperatures had a strong north to south increasing trend, with annual average varying from -1 to 24 °C, and growing season average temperature varying from 8 to 30 °C. DTR gradually decreased from western to eastern parts of the region, with a regional annual and growing season averages of 14.25 °C and 14.79 °C, respectively. Precipitation had a gradual shift towards higher magnitudes from west to east, with the average annual and growing season (May-September) precipitation ranging from 163 to 1486 mm and from 98 to 746 mm, respectively. ETo had a southwest-northeast decreasing trend, with regional annual and growing season averages of 1297 mm and 823 mm, respectively. AI increased from west to east, indicating higher humidity (less arid) towards the east, with regional annual and growing season averages of 0.49 and 0.44, respectively. The spatial datasets and maps for these important climate variables can serve as valuable background for climate change and hydrologic studies in the Great Plains region. Through identification of priority areas from the developed maps, efforts of the concerned personnel and agencies and resources can be diverted towards development

  10. Bearings Only Air-to-Air Ranging

    DTIC Science & Technology

    1988-07-25

    sensor, observer and target parameters still remain. In order to reduce the number of cases to a manageable one, while preserving the geometric...perforance of variotu. ulro-air passive ranging tecnique has been examined as a fimn- tiam of uarget location andi motiom, observer motion. and length

  11. Long-term patterns of air temperatures, daily temperature range, precipitation, grass-reference evapotranspiration and aridity index in the USA great plains: Part II. Temporal trends

    NASA Astrophysics Data System (ADS)

    Kukal, M.; Irmak, S.

    2016-11-01

    Detection of long-term changes in climate variables over large spatial scales is a very important prerequisite to the development of effective mitigation and adaptation measures for the future potential climate change and for developing strategies for future hydrologic balance analyses under changing climate. Moreover, there is a need for effective approaches of providing information about these changes to decision makers, water managers and stakeholders to aid in efficient implementation of the developed strategies. This study involves computation, mapping and analyses of long-term (1968-2013) county-specific trends in annual, growing-season (1st May-30th September) and monthly air temperatures [(maximum (Tmax), minimum (Tmin) and average (Tavg)], daily temperature range (DTR), precipitation, grass reference evapotranspiration (ETo) and aridity index (AI) over the USA Great Plains region using datasets from over 800 weather station sites. Positive trends in annual Tavg, Tmax and Tmin, DTR, precipitation, ETo and AI were observed in 71%, 89%, 85%, 31%, 61%, 38% and 66% of the counties in the region, respectively, whereas these proportions were 48%, 89%, 62%, 20%, 57%, 28%, and 63%, respectively, for the growing-season averages of the same variables. On a regional average basis, the positive trends in growing-season Tavg, Tmax and Tmin, DTR, precipitation, ETo and AI were 0.18 °C decade-1, 0.19 °C decade-1, 0.17 °C decade-1, 0.09 °C decade-1, 1.12 mm yr-1, 0.4 mm yr-1 and 0.02 decade-1, respectively, and the negative trends were 0.21 °C decade-1, 0.06 °C decade-1, 0.09 °C decade-1, 0.22 °C decade-1, 1.16 mm yr-1, 0.76 mm yr-1 and 0.02 decade-1, respectively. The temporal trends were highly variable in space and were appropriately represented using monthly, annual and growing-season maps developed using Geographic Information System (GIS) techniques. The long-term and spatial and temporal information and data for a large region provided in this study can be

  12. Provide a suitable range to include the thermal creeping effect on slip velocity and temperature jump of an air flow in a nanochannel by lattice Boltzmann method

    NASA Astrophysics Data System (ADS)

    Karimipour, Arash

    2017-01-01

    The thermal creeping effect on slip velocity of air forced convection through a nanochannel is studied for the first time by using a lattice Boltzmann method. The nanochannel side walls are kept hot while the cold inlet air streams along them. The computations are presented for the wide range of Reynolds number, Knudsen number and Eckert number while slip velocity and temperature jump effects are involved. Moreover appropriate validations are performed versus previous works concerned the micro-nanoflows. The achieved results are shown as the velocity and temperature profiles at different cross sections, streamlines and isotherms and also the values of slip velocity and temperature jump along the nanochannel walls. The ability of the lattice Boltzmann method to simulate the thermal creeping effects on hydrodynamic and thermal domains of flow is shown at this study; so that its effects should be involved at lower values of Eckert number and higher values of Reynolds number especially at entrance region where the most temperature gradient exists.

  13. Contrails reduce daily temperature range.

    PubMed

    Travis, David J; Carleton, Andrew M; Lauritsen, Ryan G

    2002-08-08

    The potential of condensation trails (contrails) from jet aircraft to affect regional-scale surface temperatures has been debated for years, but was difficult to verify until an opportunity arose as a result of the three-day grounding of all commercial aircraft in the United States in the aftermath of the terrorist attacks on 11 September 2001. Here we show that there was an anomalous increase in the average diurnal temperature range (that is, the difference between the daytime maximum and night-time minimum temperatures) for the period 11-14 September 2001. Because persisting contrails can reduce the transfer of both incoming solar and outgoing infrared radiation and so reduce the daily temperature range, we attribute at least a portion of this anomaly to the absence of contrails over this period.

  14. Minimization of temperature ranges between the top and bottom of an air flow controlling device through hybrid control in a plant factory.

    PubMed

    Moon, Seung-Mi; Kwon, Sook-Youn; Lim, Jae-Hyun

    2014-01-01

    To maintain the production timing, productivity, and product quality of plant factories, it is necessary to keep the growth environment uniform. A vertical multistage type of plant factory involves different levels of growing trays, which results in the problem of difference in temperature among vertically different locations. To address it, it is necessary to install air flow devices such as air flow fan and cooling/heating device at the proper locations in order to facilitate air circulation in the facility as well as develop a controlling technology for efficient operation. Accordingly, this study compares the temperature and air distribution within the space of a vertical multistage closed-type plant factory by controlling cooling/heating devices and air flow fans harmoniously by means of the specially designed testbed. The experiment results indicate that in the hybrid control of cooling and heating devices and air flow fans, the difference in temperature decreased by as much as 78.9% compared to that when only cooling and heating devices were operated; the air distribution was improved by as much as 63.4%.

  15. Minimization of Temperature Ranges between the Top and Bottom of an Air Flow Controlling Device through Hybrid Control in a Plant Factory

    PubMed Central

    2014-01-01

    To maintain the production timing, productivity, and product quality of plant factories, it is necessary to keep the growth environment uniform. A vertical multistage type of plant factory involves different levels of growing trays, which results in the problem of difference in temperature among vertically different locations. To address it, it is necessary to install air flow devices such as air flow fan and cooling/heating device at the proper locations in order to facilitate air circulation in the facility as well as develop a controlling technology for efficient operation. Accordingly, this study compares the temperature and air distribution within the space of a vertical multistage closed-type plant factory by controlling cooling/heating devices and air flow fans harmoniously by means of the specially designed testbed. The experiment results indicate that in the hybrid control of cooling and heating devices and air flow fans, the difference in temperature decreased by as much as 78.9% compared to that when only cooling and heating devices were operated; the air distribution was improved by as much as 63.4%. PMID:25013867

  16. Ice core evidence of rapid air temperature increases since 1960 in alpine areas of the Wind River Range, Wyoming, United States

    USGS Publications Warehouse

    Naftz, D.L.; Susong, D.D.; Schuster, P.F.; Cecil, L.D.; Dettinger, M.D.; Michel, R.L.; Kendall, C.

    2002-01-01

    Site-specific transfer functions relating delta oxygen 18 (δ18O) values in snow to the average air temperature (TA) during storms on Upper Fremont Glacier (UFG) were used in conjunction with δ18O records from UFG ice cores to reconstruct long-term trends in air temperature from alpine areas in the Wind River Range, Wyoming. Transfer functions were determined by using data collected from four seasonal snowpacks (1989-1990, 1997-1998, 1998-1999, and 1999-2000). The timing and amount of each storm was determined from an automated snowpack telemetry (SNOTEL) site, 22 km northeast of UFG, and ~1060 m in elevation below UFG. Statistically significant and positive correlations between δ18O values in the snow and TA were consistently found in three of the four seasonal snowpacks. The snowpack with the poor correlation was deposited in 1997-1998 during the 1997-1998 El Nino Southern Oscillation (ENSO). An ultrasonic snow-depth sensor installed on UFG provided valuable insights into site-specific storms and postdepositional processes that occur on UFG. The timing of storms recorded at the UFG and Cold Springs SNOTEL sites were similar; however, selected storms did not correlate. Snow from storms occurring after mid-October and followed by high winds was most susceptible to redeposition of snow. This removal of lower temperature snowfall could potentially bias the δ18O values preserved in ice core records to environmental conditions reflecting higher air temperatures and lower wind speeds. Transfer functions derived from seasonal snow cover on UFG were used to reconstruct TA values from δ18O values determined from two ice cores collected from UFG. Reconstructed air temperatures from the ice core data indicate an increase in TA of ~3.5oC from the mid-1960s to the early 1990s in the alpine areas of northwestern Wyoming. Reconstructed TA from the ice core records between the end of the Little Ice Age (LIA), mid-1800s, and the early 1990s indicate a TA increase of ~55oC. The

  17. The Relationship Between Air Temperature and Stream Temperature

    NASA Astrophysics Data System (ADS)

    Morrill, J. C.; Bales, R. C.; Conklin, M. H.

    2001-05-01

    This study examined the relationship, both linear and non-linear, between air temperature and stream temperature in order to determine if air temperature can be used as an accurate predictor of stream temperature, if general relationships could be developed that apply to a large number of streams, and how changes in stream temperature associated with climate variability or climate warming might affect the dissolved oxygen level, and thus the quality of life, in some of these streams. Understanding the relationship between air temperature and water temperature is important if we want to predict how stream temperatures are likely to respond to the increase in surface air temperature that is occurring. Data from over 50 streams in 13 countries, mostly gathered by K-12 students in the GLOBE program (Global Learning and Observations to Benefit the Environment), are examined. Only a few streams display a linear 1:1 air/water temperature trend. The majority of streams instead show an increase in water temperature of about 0.6 to 0.8 degrees for every 1-degree increase in air temperature. At some of these sites, where dissolved oxygen content is already low, an increase in summer stream temperatures of 2-3 degrees could cause the dissolved oxygen levels to fall into a critically low range. At some locations, such as near the source of a stream, water temperature does not change much despite wide ranges in air temperatures. The temperatures at these sites are likely to be least affected by surface warming. More data are needed in warmer climates, where the water temperature already gets above 25oC, in order to better examine the air/water temperature relationship under warmer conditions. Global average surface air temperature is expected to increase by 3-5oC by the middle of this century. Surface water temperature in streams, lakes and wetlands will likely increase as air temperature increases, although the change in water temperature may not be as large as the change in

  18. Temperature Tunable Air-Gap Etalon Filter

    NASA Technical Reports Server (NTRS)

    Krainak, Michael A.; Stephen, Mark A.; Lunt, David L.

    1998-01-01

    We report on experimental measurements of a temperature tuned air-gap etalon filter. The filter exhibits temperature dependent wavelength tuning of 54 pm/C. It has a nominal center wavelength of 532 nm. The etalon filter has a 27 pm optical bandpass and 600 pm free spectral range (finesse approximately 22). The experimental results are in close agreement with etalon theory.

  19. Tracking far-range volcanogenic air pollution

    NASA Astrophysics Data System (ADS)

    Boichu, Marie; Chiapello, Isabelle; Goloub, Phillipe; Péré, Jean-Christophe; Thieuleux, François; Blarel, Luc; Podvin, Thierry; Mortier, Augustin; Brogniez, Colette; Sohne, Nathalie; Theys, Nicolas; Van Roozendael, Michel; Clarisse, Lieven; Bauduin, Sophie; Tanré, Didier

    2016-04-01

    The 2014-15 Holuhraun lava-flood eruption of Bárdarbunga volcano (Iceland) emitted prodigious amounts of sulfur dioxide to the atmosphere. This eruption triggered a long-distance episode of air pollution in September 2014, the first event of this magnitude recorded in the modern era. We gathered a wealth of complementary observations from satellite sensors (OMI, IASI), ground-based remote sensing (lidar, sunphotometry, differential optical absorption spectroscopy) and ground-level air quality monitoring networks to characterize both the spatial distribution of volcanic SO2 and aerosols as well as the dynamics of the planetary boundary layer. We take advantage of this exceptional panel of observations to quantitatively test our modeling ability to retrospectively simulate this event of far-range air pollution. Although the model captures the correct temporal dynamics, it fails to reproduce the intensity of the pollution. Paths worth exploring to get prepared to accurately forecast a future large-scale event of volcanogenic air pollution are discussed.

  20. Undulator Hall Air Temperature Fault Scenarios

    SciTech Connect

    Sevilla, J.; Welch, J.; /SLAC

    2010-11-17

    Recent experience indicates that the LCLS undulator segments must not, at any time following tuning, be allowed to change temperature by more than about {+-}2.5 C or the magnetic center will irreversibly shift outside of acceptable tolerances. This vulnerability raises a concern that under fault conditions the ambient temperature in the Undulator Hall might go outside of the safe range and potentially could require removal and retuning of all the segments. In this note we estimate changes that can be expected in the Undulator Hall air temperature for three fault scenarios: (1) System-wide power failure; (2) Heating Ventilation and Air Conditioning (HVAC) system shutdown; and (3) HVAC system temperature regulation fault. We find that for either a system-wide power failure or an HVAC system shutdown (with the technical equipment left on), the short-term temperature changes of the air would be modest due to the ability of the walls and floor to act as a heat ballast. No action would be needed to protect the undulator system in the event of a system-wide power failure. Some action to adjust the heat balance, in the case of the HVAC power failure with the equipment left on, might be desirable but is not required. On the other hand, a temperature regulation failure of the HVAC system can quickly cause large excursions in air temperature and prompt action would be required to avoid damage to the undulator system.

  1. Air sampler performance at Ford's farm range

    SciTech Connect

    Glissmeyer, J.A.; Johnston, J.W.

    1984-07-01

    An air-sampling system for a large-caliber depleted uranium (DU) penetrator firing range was tested. The objectives of the test were: to determine the bias between the monitoring readings and DU concentrations; and to determine if the target bay real-time monitor (RTM) tracks the decaying dust concentration. The test procedure was to operate total and respirable airborne particle samplers adjacent to the target bay monitors. A series of air samples was also taken after the test firings adjacent to the target bay RTM. Exhaust particle samples were analyzed for gross alpha, gross beta and uranium content. The target bay RTM correlated well (0.977) with the sequential samples. Average concentration from the RTM did not correlate with either the long-term total or respirable sampler DU concentrations. The monitor used to confirm a low dust concentration when the door is open correlated well (0.810) with the RTM; the other bay monitor did not. In the ventilation discharge, the long-term average monitor readings did not correlate with DU concentrations, probably due to levels near lower detection limits. Smearable surface-contamination samples showed highest contamination on the equipment, gravel floor and exhaust intake. The location air-intake contamination increased over the first 3 rounds. Contamination was reduced by a low-pressure water spray washdown to about the same concentration as often the second round, then remained at about twice the level. 2 references, 18 figures, 16 tables. (MF)

  2. Wide temperature range seal for demountable joints

    DOEpatents

    Sixsmith, Herbert; Valenzuela, Javier A.; Nutt, William E.

    1991-07-23

    The present invention is directed to a seal for demountable joints operating over a wide temperature range down to liquid helium temperatures. The seal has anti-extrusion guards which prevent extrusion of the soft ductile sealant material, which may be indium or an alloy thereof.

  3. Wide temperature range seal for demountable joints

    DOEpatents

    Sixsmith, H.; Valenzuela, J.A.; Nutt, W.E.

    1991-07-23

    The present invention is directed to a seal for demountable joints operating over a wide temperature range down to liquid helium temperatures. The seal has anti-extrusion guards which prevent extrusion of the soft ductile sealant material, which may be indium or an alloy thereof. 6 figures.

  4. Solid oxide fuel cell operable over wide temperature range

    DOEpatents

    Baozhen, Li; Ruka, Roswell J.; Singhal, Subhash C.

    2001-01-01

    Solid oxide fuel cells having improved low-temperature operation are disclosed. In one embodiment, an interfacial layer of terbia-stabilized zirconia is located between the air electrode and electrolyte of the solid oxide fuel cell. The interfacial layer provides a barrier which controls interaction between the air electrode and electrolyte. The interfacial layer also reduces polarization loss through the reduction of the air electrode/electrolyte interfacial electrical resistance. In another embodiment, the solid oxide fuel cell comprises a scandia-stabilized zirconia electrolyte having high electrical conductivity. The scandia-stabilized zirconia electrolyte may be provided as a very thin layer in order to reduce resistance. The scandia-stabilized electrolyte is preferably used in combination with the terbia-stabilized interfacial layer. The solid oxide fuel cells are operable over wider temperature ranges and wider temperature gradients in comparison with conventional fuel cells.

  5. Surface Temperature variability from AIRS.

    NASA Astrophysics Data System (ADS)

    Ruzmaikin, A.; Dang, V. T.; Aumann, H. H.

    2015-12-01

    To address the existence and possible causes of the climate hiatus in the Earth's global temperature we investigate the trends and variability in the surface temperature using retrievals obtained from the measurements by the Atmospheric Infrared Sounder (AIRS) and its companion instrument, the Advanced Microwave Sounding Unit (AMSU), onboard of Aqua spacecraft in 2002-2014for the day and night conditions. The data used are L3 monthly means on a 1x1degree spatial grid. We separate the land and ocean temperatures, as well as temperatures in Artic, Antarctic and desert regions. We compare the satellite data with the new surface data produced by Karl et al. (2015) who denies the reality of the climate hiatus. The difference in the regional trends can help to explain why the global surface temperature remains almost unchanged but the frequency of occurrence of the extreme events increases under rising anthropogenic forcing. The day-night difference is an indicator of the anthropogenic trend. This work was supported by the Jet Propulsion Laboratory of the California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

  6. Wide-Temperature-Range Integrated Operational Amplifier

    NASA Technical Reports Server (NTRS)

    Mojarradi, Mohammad; Levanas, Greg; Chen, Yuan; Kolawa, Elizabeth; Cozy, Raymond; Blalock, Benjamin; Greenwell, Robert; Terry, Stephen

    2007-01-01

    A document discusses a silicon-on-insulator (SOI) complementary metal oxide/semiconductor (CMOS) integrated- circuit operational amplifier to be replicated and incorporated into sensor and actuator systems of Mars-explorer robots. This amplifier is designed to function at a supply potential less than or equal to 5.5 V, at any temperature from -180 to +120 C. The design is implemented on a commercial radiation-hard SOI CMOS process rated for a supply potential of less than or equal to 3.6 V and temperatures from -55 to +110 C. The design incorporates several innovations to achieve this, the main ones being the following: NMOS transistor channel lengths below 1 m are generally not used because research showed that this change could reduce the adverse effect of hot carrier injection on the lifetimes of transistors at low temperatures. To enable the amplifier to withstand the 5.5-V supply potential, a circuit topology including cascade devices, clamping devices, and dynamic voltage biasing was adopted so that no individual transistor would be exposed to more than 3.6 V. To minimize undesired variations in performance over the temperature range, the transistors in the amplifier are biased by circuitry that maintains a constant inversion coefficient over the temperature range.

  7. The expectation of applying IR guidance in medium range air-to-air missiles

    NASA Astrophysics Data System (ADS)

    Li, Lijuan; Liu, Ke

    2016-10-01

    IR guidance has been widely used in near range dogfight air-to-air missiles while radar guidance is dominant in medium and long range air-to-air missiles. With the development of stealth airplanes and advanced electronic countermeasures, radar missiles have met with great challenges. In this article, the advantages and potential problems of applying IR guidance in medium range air-to-air missiles are analyzed. Approaches are put forward to solve the key technologies including depressing aerodynamic heating, increasing missiles' sensitivity and acquiring target after launch. IR medium range air-to-air missiles are predicted to play important role in modern battle field.

  8. Crowdsourcing urban air temperatures from smartphone battery temperatures

    NASA Astrophysics Data System (ADS)

    Overeem, Aart; Robinson, James C. R.; Leijnse, Hidde; Steeneveld, Gert-Jan; Horn, Berthold K. P.; Uijlenhoet, Remko

    2014-05-01

    Accurate air temperature observations in urban areas are important for meteorology and energy demand planning. They are indispensable to study the urban heat island effect and the adverse effects of high temperatures on human health. However, the availability of temperature observations in cities is often limited. Here we show that relatively accurate air temperature information for the urban canopy layer can be obtained from an alternative, nowadays omnipresent source: smartphones. In this study, battery temperatures were collected by an Android application for smartphones. It has been shown that a straightforward heat transfer model can be employed to estimate daily mean air temperatures from smartphone battery temperatures for eight major cities around the world. The results demonstrate the enormous potential of this crowdsourcing application for real-time temperature monitoring in densely populated areas. Battery temperature data were collected by users of an Android application for cell phones (opensignal.com). The application automatically sends battery temperature data to a server for storage. In this study, battery temperatures are averaged in space and time to obtain daily averaged battery temperatures for each city separately. A regression model, which can be related to a physical model, is employed to retrieve daily air temperatures from battery temperatures. The model is calibrated with observed air temperatures from a meteorological station of an airport located in or near the city. Time series of air temperatures are obtained for each city for a period of several months, where 50% of the data is for independent verification. The methodology has been applied to Buenos Aires, London, Los Angeles, Paris, Mexico City, Moscow, Rome, and Sao Paulo. The evolution of the retrieved air temperatures often correspond well with the observed ones. The mean absolute error of daily air temperatures is less than 2 degrees Celsius, and the bias is within 1 degree

  9. Active Behavior Recognition in Beyond Visual Range Air Combat

    DTIC Science & Technology

    2015-05-01

    Active Behavior Recognition in Beyond Visual Range Air Combat Ron Alford RONALD.ALFORD.CTR@NRL.NAVY.MIL ASEE Postdoctoral Fellow; Naval Research...planning and recognition, as well as its im- plementation in a beyond visual range air combat simulator. We found that it yields better behavior recognition...SUBTITLE Active Behavior Recognition in Beyond Visual Range Air Combat 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR

  10. 33 CFR 334.1280 - Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force. 334.1280 Section 334.1280 Navigation and Navigable... REGULATIONS § 334.1280 Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force....

  11. 33 CFR 334.1280 - Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force. 334.1280 Section 334.1280 Navigation and Navigable... REGULATIONS § 334.1280 Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force....

  12. 33 CFR 334.1280 - Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force. 334.1280 Section 334.1280 Navigation and Navigable... REGULATIONS § 334.1280 Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force....

  13. 33 CFR 334.1280 - Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force. 334.1280 Section 334.1280 Navigation and Navigable... REGULATIONS § 334.1280 Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force....

  14. 33 CFR 334.1280 - Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force. 334.1280 Section 334.1280 Navigation and Navigable... REGULATIONS § 334.1280 Bristol Bay, Alaska; air-to-air weapon range, Alaskan Air Command, U.S. Air Force....

  15. Honeybee flight metabolic rate: does it depend upon air temperature?

    PubMed

    Woods, William A; Heinrich, Bernd; Stevenson, Robert D

    2005-03-01

    Differing conclusions have been reached as to how or whether varying heat production has a thermoregulatory function in flying honeybees Apis mellifera. We investigated the effects of air temperature on flight metabolic rate, water loss, wingbeat frequency, body segment temperatures and behavior of honeybees flying in transparent containment outdoors. For periods of voluntary, uninterrupted, self-sustaining flight, metabolic rate was independent of air temperature between 19 and 37 degrees C. Thorax temperatures (T(th)) were very stable, with a slope of thorax temperature on air temperature of 0.18. Evaporative heat loss increased from 51 mW g(-1) at 25 degrees C to 158 mW g(-1) at 37 degrees C and appeared to account for head and abdomen temperature excess falling sharply over the same air temperature range. As air temperature increased from 19 to 37 degrees C, wingbeat frequency showed a slight but significant increase, and metabolic expenditure per wingbeat showed a corresponding slight but significant decrease. Bees spent an average of 52% of the measurement period in flight, with 19 of 78 bees sustaining uninterrupted voluntary flight for periods of >1 min. The fraction of time spent flying declined as air temperature increased. As the fraction of time spent flying decreased, the slope of metabolic rate on air temperature became more steeply negative, and was significant for bees flying less than 80% of the time. In a separate experiment, there was a significant inverse relationship of metabolic rate and air temperature for bees requiring frequent or constant agitation to remain airborne, but no dependence for bees that flew with little or no agitation; bees were less likely to require agitation during outdoor than indoor measurements. A recent hypothesis explaining differences between studies in the slope of flight metabolic rate on air temperature in terms of differences in metabolic capacity and thorax temperature is supported for honeybees in voluntary

  16. Effect of Initial Mixture Temperature on Flame Speed of Methane-Air, Propane-Air, and Ethylene-Air Mixtures

    NASA Technical Reports Server (NTRS)

    Dugger, Gordon L

    1952-01-01

    Flame speeds based on the outer edge of the shadow cast by the laminar Bunsen cone were determined as functions of composition for methane-air mixtures at initial mixture temperatures ranging from -132 degrees to 342 degrees c and for propane-air and ethylene-air mixtures at initial mixture temperatures ranging from -73 degrees to 344 degrees c. The data showed that maximum flame speed increased with temperature at an increasing rate. The percentage change in flame speed with change in initial temperature for the three fuels followed the decreasing order, methane, propane, and ethylene. Empirical equations were determined for maximum flame speed as a function of initial temperature over the temperature range covered for each fuel. The observed effect of temperature on flame speed for each of the fuels was reasonably well predicted by either the thermal theory as presented by Semenov or the square-root law of Tanford and Pease.

  17. Extended temperature range ACPS thruster investigation

    NASA Technical Reports Server (NTRS)

    Blubaugh, A. L.; Schoenman, L.

    1974-01-01

    The successful hot fire demonstration of a pulsing liquid hydrogen/liquid oxygen and gaseous hydrogen/liquid oxygen attitude control propulsion system thruster is described. The test was the result of research to develop a simple, lightweight, and high performance reaction control system without the traditional requirements for extensive periods of engine thermal conditioning, or the use of complex equipment to convert both liquid propellants to gas prior to delivery to the engine. Significant departures from conventional injector design practice were employed to achieve an operable design. The work discussed includes thermal and injector manifold priming analyses, subscale injector chilldown tests, and 168 full scale and 550 N (1250 lbF) rocket engine tests. Ignition experiments, at propellant temperatures ranging from cryogenic to ambient, led to the generation of a universal spark ignition system which can reliably ignite an engine when supplied with liquid, two phase, or gaseous propellants. Electrical power requirements for spark igniter are very low.

  18. Crowdsourcing urban air temperatures from smartphone battery temperatures

    NASA Astrophysics Data System (ADS)

    Overeem, A.; Robinson, J. C. R.; Leijnse, H.; Steeneveld, G. J.; Horn, B. K. P.; Uijlenhoet, R.

    2013-08-01

    Accurate air temperature observations in urban areas are important for meteorology and energy demand planning. They are indispensable to study the urban heat island effect and the adverse effects of high temperatures on human health. However, the availability of temperature observations in cities is often limited. Here we show that relatively accurate air temperature information for the urban canopy layer can be obtained from an alternative, nowadays omnipresent source: smartphones. In this study, battery temperatures were collected by an Android application for smartphones. A straightforward heat transfer model is employed to estimate daily mean air temperatures from smartphone battery temperatures for eight major cities around the world. The results demonstrate the enormous potential of this crowdsourcing application for real-time temperature monitoring in densely populated areas.

  19. Controlled-Temperature Hot-Air Gun

    NASA Technical Reports Server (NTRS)

    Munoz, M. C.

    1986-01-01

    Materials that find applications in wind tunnels first tested in laboratory. Hot-Air Gun differs from commercial units in that flow rate and temperature monitored and controlled. With typical compressed-airsupply pressure of 25 to 38 psi (170 to 260 kPa), flow rate and maximum temperature are 34 stdft3/min (0.96 stdm3/min) and 1,090 degrees F (590 degrees C), respectively. Resembling elaborate but carefully regulated hot-air gun, setup used to apply blasts of air temperatures above 1,500 degrees F (815 degrees C) to test specimens.

  20. Ambient air temperature effects on the temperature of sewage sludge composting process.

    PubMed

    Huang, Qi-fei; Chen, Tong-bin; Gao, Ding; Huang, Ze-chun

    2005-01-01

    Using data obtained with a full-scale sewage sludge composting facility, this paper studied the effects of ambient air temperature on the composting temperature with varying volume ratios of sewage sludge and recycled compost to bulking agent. Two volume ratios were examined experimentally, 1: 0: 1 and 3: 1: 2. The results show that composting temperature was influenced by ambient air temperature and the influence was more significant when composting was in the temperature rising process: composting temperature changed 2.4-6.5 degrees C when ambient air temperature changed 13 degrees C. On the other hand, the influence was not significant when composting was in the high-temperature and/or temperature falling process: composting temperature changed 0.75-1.3 degrees C when ambient air temperature changed 8-15 degrees C. Hysteresis effect was observed in composting temperature's responses to ambient air temperature. When the ventilation capability of pile was excellent (at a volume ratio of 1:0:1), the hysteresis time was short and ranging 1.1-1.2 h. On the contrary, when the proportion of added bulking agent was low, therefore less porosity in the substrate (at a volume ratio of 3:1:2), the hysteresis time was long and ranging 1.9-3.1 h.

  1. Air separation with temperature and pressure swing

    DOEpatents

    Cassano, Anthony A.

    1986-01-01

    A chemical absorbent air separation process is set forth which uses a temperature swing absorption-desorption cycle in combination with a pressure swing wherein the pressure is elevated in the desorption stage of the process.

  2. Air Temperature in the Undulator Hall

    SciTech Connect

    Not Available

    2010-12-07

    Various analyses have been performed recently to estimate the performance of the air conditioning (HVAC) system planned for the Undulator Hall. This reports summarizes the results and provides an upgrade plan to be used if new requirements are needed in the future. The estimates predict that with the planned loads the tunnel air temperature will be well within the allowed tolerance during normal operation.

  3. Variation in the urban vegetation, surface temperature, air temperature nexus.

    PubMed

    Shiflett, Sheri A; Liang, Liyin L; Crum, Steven M; Feyisa, Gudina L; Wang, Jun; Jenerette, G Darrel

    2017-02-01

    Our study examines the urban vegetation - air temperature (Ta) - land surface temperature (LST) nexus at micro- and regional-scales to better understand urban climate dynamics and the uncertainty in using satellite-based LST for characterizing Ta. While vegetated cooling has been repeatedly linked to reductions in urban LST, the effects of vegetation on Ta, the quantity often used to characterize urban heat islands and global warming, and on the interactions between LST and Ta are less well characterized. To address this need we quantified summer temporal and spatial variation in Ta through a network of 300 air temperature sensors in three sub-regions of greater Los Angeles, CA, which spans a coastal to desert climate gradient. Additional sensors were placed within the inland sub-region at two heights (0.1m and 2m) within three groundcover types: bare soil, irrigated grass, and underneath citrus canopy. For the entire study region, we acquired new imagery data, which allowed calculation of the normalized difference vegetation index (NDVI) and LST. At the microscale, daytime Ta measured along a vertical gradient, ranged from 6 to 3°C cooler at 0.1 and 2m, underneath tall canopy compared to bare ground respectively. At the regional scale NDVI and LST were negatively correlated (p<0.001). Relationships between diel variation in Ta and daytime LST at the regional scale were progressively weaker moving away from the coast and were generally limited to evening and nighttime hours. Relationships between NDVI and Ta were stronger during nighttime hours, yet effectiveness of mid-day vegetated cooling increased substantially at the most arid region. The effectiveness of vegetated Ta cooling increased during heat waves throughout the region. Our findings suggest an important but complex role of vegetation on LST and Ta and that vegetation may provide a negative feedback to urban climate warming.

  4. Nowcasting daily minimum air and grass temperature.

    PubMed

    Savage, M J

    2016-02-01

    Site-specific and accurate prediction of daily minimum air and grass temperatures, made available online several hours before their occurrence, would be of significant benefit to several economic sectors and for planning human activities. Site-specific and reasonably accurate nowcasts of daily minimum temperature several hours before its occurrence, using measured sub-hourly temperatures hours earlier in the morning as model inputs, was investigated. Various temperature models were tested for their ability to accurately nowcast daily minimum temperatures 2 or 4 h before sunrise. Temperature datasets used for the model nowcasts included sub-hourly grass and grass-surface (infrared) temperatures from one location in South Africa and air temperature from four subtropical sites varying in altitude (USA and South Africa) and from one site in central sub-Saharan Africa. Nowcast models used employed either exponential or square root functions to describe the rate of nighttime temperature decrease but inverted so as to determine the minimum temperature. The models were also applied in near real-time using an open web-based system to display the nowcasts. Extrapolation algorithms for the site-specific nowcasts were also implemented in a datalogger in an innovative and mathematically consistent manner. Comparison of model 1 (exponential) nowcasts vs measured daily minima air temperatures yielded root mean square errors (RMSEs) <1 °C for the 2-h ahead nowcasts. Model 2 (also exponential), for which a constant model coefficient (b = 2.2) was used, was usually slightly less accurate but still with RMSEs <1 °C. Use of model 3 (square root) yielded increased RMSEs for the 2-h ahead comparisons between nowcasted and measured daily minima air temperature, increasing to 1.4 °C for some sites. For all sites for all models, the comparisons for the 4-h ahead air temperature nowcasts generally yielded increased RMSEs, <2.1 °C. Comparisons for all model nowcasts of the daily grass

  5. Nowcasting daily minimum air and grass temperature

    NASA Astrophysics Data System (ADS)

    Savage, M. J.

    2016-02-01

    Site-specific and accurate prediction of daily minimum air and grass temperatures, made available online several hours before their occurrence, would be of significant benefit to several economic sectors and for planning human activities. Site-specific and reasonably accurate nowcasts of daily minimum temperature several hours before its occurrence, using measured sub-hourly temperatures hours earlier in the morning as model inputs, was investigated. Various temperature models were tested for their ability to accurately nowcast daily minimum temperatures 2 or 4 h before sunrise. Temperature datasets used for the model nowcasts included sub-hourly grass and grass-surface (infrared) temperatures from one location in South Africa and air temperature from four subtropical sites varying in altitude (USA and South Africa) and from one site in central sub-Saharan Africa. Nowcast models used employed either exponential or square root functions to describe the rate of nighttime temperature decrease but inverted so as to determine the minimum temperature. The models were also applied in near real-time using an open web-based system to display the nowcasts. Extrapolation algorithms for the site-specific nowcasts were also implemented in a datalogger in an innovative and mathematically consistent manner. Comparison of model 1 (exponential) nowcasts vs measured daily minima air temperatures yielded root mean square errors (RMSEs) <1 °C for the 2-h ahead nowcasts. Model 2 (also exponential), for which a constant model coefficient ( b = 2.2) was used, was usually slightly less accurate but still with RMSEs <1 °C. Use of model 3 (square root) yielded increased RMSEs for the 2-h ahead comparisons between nowcasted and measured daily minima air temperature, increasing to 1.4 °C for some sites. For all sites for all models, the comparisons for the 4-h ahead air temperature nowcasts generally yielded increased RMSEs, <2.1 °C. Comparisons for all model nowcasts of the daily grass

  6. Modeling monthly mean air temperature for Brazil

    NASA Astrophysics Data System (ADS)

    Alvares, Clayton Alcarde; Stape, José Luiz; Sentelhas, Paulo Cesar; de Moraes Gonçalves, José Leonardo

    2013-08-01

    Air temperature is one of the main weather variables influencing agriculture around the world. Its availability, however, is a concern, mainly in Brazil where the weather stations are more concentrated on the coastal regions of the country. Therefore, the present study had as an objective to develop models for estimating monthly and annual mean air temperature for the Brazilian territory using multiple regression and geographic information system techniques. Temperature data from 2,400 stations distributed across the Brazilian territory were used, 1,800 to develop the equations and 600 for validating them, as well as their geographical coordinates and altitude as independent variables for the models. A total of 39 models were developed, relating the dependent variables maximum, mean, and minimum air temperatures (monthly and annual) to the independent variables latitude, longitude, altitude, and their combinations. All regression models were statistically significant ( α ≤ 0.01). The monthly and annual temperature models presented determination coefficients between 0.54 and 0.96. We obtained an overall spatial correlation higher than 0.9 between the models proposed and the 16 major models already published for some Brazilian regions, considering a total of 3.67 × 108 pixels evaluated. Our national temperature models are recommended to predict air temperature in all Brazilian territories.

  7. Modeling of global surface air temperature

    NASA Astrophysics Data System (ADS)

    Gusakova, M. A.; Karlin, L. N.

    2012-04-01

    A model to assess a number of factors, such as total solar irradiance, albedo, greenhouse gases and water vapor, affecting climate change has been developed on the basis of Earth's radiation balance principle. To develop the model solar energy transformation in the atmosphere was investigated. It's a common knowledge, that part of the incoming radiation is reflected into space from the atmosphere, land and water surfaces, and another part is absorbed by the Earth's surface. Some part of outdoing terrestrial radiation is retained in the atmosphere by greenhouse gases (carbon dioxide, methane, nitrous oxide) and water vapor. Making use of the regression analysis a correlation between concentration of greenhouse gases, water vapor and global surface air temperature was obtained which, it is turn, made it possible to develop the proposed model. The model showed that even smallest fluctuations of total solar irradiance intensify both positive and negative feedback which give rise to considerable changes in global surface air temperature. The model was used both to reconstruct the global surface air temperature for the 1981-2005 period and to predict global surface air temperature until 2030. The reconstructions of global surface air temperature for 1981-2005 showed the models validity. The model makes it possible to assess contribution of the factors listed above in climate change.

  8. 33 CFR 334.700 - Choctawhatchee Bay, aerial gunnery ranges, Air Proving Ground Center, Air Research and...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... gunnery ranges, Air Proving Ground Center, Air Research and Development Command, Eglin Air Force Base, Fla... gunnery ranges, Air Proving Ground Center, Air Research and Development Command, Eglin Air Force Base, Fla... regulations in this section shall be enforced by the Commander, Air Proving Ground Center, Eglin AFB, and...

  9. 33 CFR 334.700 - Choctawhatchee Bay, aerial gunnery ranges, Air Proving Ground Center, Air Research and...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... gunnery ranges, Air Proving Ground Center, Air Research and Development Command, Eglin Air Force Base, Fla... gunnery ranges, Air Proving Ground Center, Air Research and Development Command, Eglin Air Force Base, Fla... regulations in this section shall be enforced by the Commander, Air Proving Ground Center, Eglin AFB, and...

  10. AIRS Retrieved Temperature Isotherms over Southern Europe

    NASA Technical Reports Server (NTRS)

    2002-01-01

    AIRS Retrieved Temperature Isotherms over Southern Europe viewed from the west, September 8, 2002. The isotherms in this map made from AIRS data show regions of the same temperature in the atmosphere.

    The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena.

  11. Modeling daily average stream temperature from air temperature and watershed area

    NASA Astrophysics Data System (ADS)

    Butler, N. L.; Hunt, J. R.

    2012-12-01

    Habitat restoration efforts within watersheds require spatial and temporal estimates of water temperature for aquatic species especially species that migrate within watersheds at different life stages. Monitoring programs are not able to fully sample all aquatic environments within watersheds under the extreme conditions that determine long-term habitat viability. Under these circumstances a combination of selective monitoring and modeling are required for predicting future geospatial and temporal conditions. This study describes a model that is broadly applicable to different watersheds while using readily available regional air temperature data. Daily water temperature data from thirty-eight gauges with drainage areas from 2 km2 to 2000 km2 in the Sonoma Valley, Napa Valley, and Russian River Valley in California were used to develop, calibrate, and test a stream temperature model. Air temperature data from seven NOAA gauges provided the daily maximum and minimum air temperatures. The model was developed and calibrated using five years of data from the Sonoma Valley at ten water temperature gauges and a NOAA air temperature gauge. The daily average stream temperatures within this watershed were bounded by the preceding maximum and minimum air temperatures with smaller upstream watersheds being more dependent on the minimum air temperature than maximum air temperature. The model assumed a linear dependence on maximum and minimum air temperature with a weighting factor dependent on upstream area determined by error minimization using observed data. Fitted minimum air temperature weighting factors were consistent over all five years of data for each gauge, and they ranged from 0.75 for upstream drainage areas less than 2 km2 to 0.45 for upstream drainage areas greater than 100 km2. For the calibration data sets within the Sonoma Valley, the average error between the model estimated daily water temperature and the observed water temperature data ranged from 0.7

  12. 40 CFR 91.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air temperature... Provisions § 91.309 Engine intake air temperature measurement. (a) Engine intake air temperature measurement... the supply system or in the air stream entering the engine. (b) The temperature measurements must...

  13. 40 CFR 91.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air temperature... Provisions § 91.309 Engine intake air temperature measurement. (a) Engine intake air temperature measurement... the supply system or in the air stream entering the engine. (b) The temperature measurements must...

  14. 40 CFR 91.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air temperature... Provisions § 91.309 Engine intake air temperature measurement. (a) Engine intake air temperature measurement... the supply system or in the air stream entering the engine. (b) The temperature measurements must...

  15. 33 CFR 159.119 - Operability test; temperature range.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Operability test; temperature... Operability test; temperature range. The device must operate in an ambient temperature of 5 °C with inlet operating fluid temperature varying from 2 °C to 32 °C and in an ambient temperature of 50 °C with...

  16. 33 CFR 159.119 - Operability test; temperature range.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Operability test; temperature... Operability test; temperature range. The device must operate in an ambient temperature of 5 °C with inlet operating fluid temperature varying from 2 °C to 32 °C and in an ambient temperature of 50 °C with...

  17. 33 CFR 159.119 - Operability test; temperature range.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Operability test; temperature... Operability test; temperature range. The device must operate in an ambient temperature of 5 °C with inlet operating fluid temperature varying from 2 °C to 32 °C and in an ambient temperature of 50 °C with...

  18. 33 CFR 159.119 - Operability test; temperature range.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Operability test; temperature... Operability test; temperature range. The device must operate in an ambient temperature of 5 °C with inlet operating fluid temperature varying from 2 °C to 32 °C and in an ambient temperature of 50 °C with...

  19. 33 CFR 159.119 - Operability test; temperature range.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Operability test; temperature... Operability test; temperature range. The device must operate in an ambient temperature of 5 °C with inlet operating fluid temperature varying from 2 °C to 32 °C and in an ambient temperature of 50 °C with...

  20. Prototype air cleaning system for a firing range

    SciTech Connect

    Glissmeyer, J.A.; Mishima, J.; Bamberger, J.A.

    1985-01-01

    This report recommends air cleaning system components for the US Army Ballistics Research Laboratory's new large-caliber firing range, which is used for testing depleted uranium (DU) penetrators. The new air cleaning system has lower operating costs during the life of the system compared to that anticipated for the existing air cleaning system. The existing system consists of three banks of filters in series; the first two banks are prefilters and the last are high-efficiency particulate air (HEPA) filters. The principal disadvantage of the existing filters is that they are not cleanable and reusable. Pacific Northwest Laboratory focused the search for alternate air cleaning equipment on devices that do not employ liquids as part of the particle collection mechanism. Collected dry particles were assumed preferable to a liquid waste stream. The dry particle collection devices identified included electrostatic precipitators; inertial separators using turning vanes or cyclones; and several devices employing a filter medium such as baghouses, cartridge houses, cleanable filters, and noncleanable filters similar to those in the existing system. The economics of practical air cleaning systems employing the dry particle collection devices were evaluated in 294 different combinations. 7 references, 21 figures, 78 tables.

  1. 33 CFR 159.115 - Temperature range test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Temperature range test. 159.115...) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.115 Temperature range test. (a) The device must be held at a temperature of 60 °C or higher for a period of 16 hours. (b) The...

  2. 33 CFR 159.115 - Temperature range test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Temperature range test. 159.115...) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.115 Temperature range test. (a) The device must be held at a temperature of 60 °C or higher for a period of 16 hours. (b) The...

  3. 33 CFR 159.115 - Temperature range test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Temperature range test. 159.115...) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.115 Temperature range test. (a) The device must be held at a temperature of 60 °C or higher for a period of 16 hours. (b) The...

  4. 33 CFR 159.115 - Temperature range test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Temperature range test. 159.115...) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.115 Temperature range test. (a) The device must be held at a temperature of 60 °C or higher for a period of 16 hours. (b) The...

  5. 33 CFR 159.115 - Temperature range test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Temperature range test. 159.115...) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.115 Temperature range test. (a) The device must be held at a temperature of 60 °C or higher for a period of 16 hours. (b) The...

  6. Modeling air temperature changes in Northern Asia

    NASA Astrophysics Data System (ADS)

    Onuchin, A.; Korets, M.; Shvidenko, A.; Burenina, T.; Musokhranova, A.

    2014-11-01

    Based on time series (1950-2005) of monthly temperatures from 73 weather stations in Northern Asia (limited by 70-180° EL and 48-75° NL), it is shown that there are statistically significant spatial differences in character and intensity of the monthly and yearly temperature trends. These differences are defined by geomorphological and geographical parameters of the area including exposure of the territory to Arctic and Pacific air mass, geographic coordinates, elevation, and distances to Arctic and Pacific oceans. Study area has been divided into six domains with unique groupings of the temperature trends based on cluster analysis. An original methodology for mapping of temperature trends has been developed and applied to the region. The assessment of spatial patterns of temperature trends at the regional level requires consideration of specific regional features in the complex of factors operating in the atmosphere-hydrosphere-lithosphere-biosphere system.

  7. AIM-120 Advanced Medium Range Air-to-Air Missile (AMRAAM)

    DTIC Science & Technology

    2015-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-185 AIM-120 Advanced Medium Range Air-to-Air Missile (AMRAAM) As of FY 2017 President’s...Program Office Estimate RDT&E - Research, Development, Test, and Evaluation SAR - Selected Acquisition Report SCP - Service Cost Position TBD - To Be

  8. Orthogonal design on range hood with air curtain and its effects on kitchen environment.

    PubMed

    Liu, Xiaomin; Wang, Xing; Xi, Guang

    2014-01-01

    Conventional range hoods cannot effectively prevent the oil fumes containing cooking-induced harmful material from escaping into the kitchen Air curtains and guide plates have been used in range hoods to reduce the escape of airborne emissions and heat, thereby improving the kitchen environment and the cook's degree of comfort. In this article, numerical simulations are used to study the effects of the jet velocity of an air curtain, the jet angle of the air curtain, the width of the jet slot, the area of the guide plate, and the exhaust rate of the range hood on the perceived temperature, the perceived concentration of oil fumes, the release temperature of oil fumes, and the concentration of escaped oil fumes in a kitchen. The orthogonal experiment results show that the exhaust rate of the range hood is the main factor influencing the fumes concentration and the temperature distribution in the kitchen. For the range hood examined in the present study, the optimum values of the exhaust rate, the jet velocity of the air curtain, the jet angle of the air curtain, the width of the jet slot, and the area of the guide plate are 10.5 m(3)/min, 1.5 m/s, -5°, 4 mm, and 0.22 m(2), respectively, based on the results of the parametric study. In addition, the velocity field, temperature field, and oil fumes concentration field in the kitchen using the proposed range hood with the air curtain and guide plate are analyzed for those parameters. The study's results provide significant information needed for improving the kitchen environment.

  9. Operating manual for Ford's Farm Range air samplers

    SciTech Connect

    Glissmeyer, J.A.; Halverson, M.A.

    1980-10-01

    An air-sampling program was designed for a target enclosure at the Ford's Farm Range, Aberdeen Proving Ground, Maryland, where the Army test-fires tungsten and depleted-uranium armor penetrators. The primary potential particle inhalation hazard is depleted uranium. The sampling program includes workplace and filtered exhaust air sampling. Conventional isokinetic stack sampling was employed for the filtered exhaust air. Because of the need for rapid monitor response to concentration increases and decreases, conventional radioactive particle monitors were not used. Instead, real-time aerosol monitors employing a light-scattering technique were used for monitors requiring a fast response. For other monitoring functions, piezoelectric and beta-attenuation respirable-particle sampling techniques were used. The application of these technologies to the monitoring of airborne radioactive contaminants is addressed. Sampler installation and operation are detailed.

  10. Pulsed positive streamer discharges in air at high temperatures

    NASA Astrophysics Data System (ADS)

    Ono, Ryo; Kamakura, Taku

    2016-08-01

    Atmospheric-pressure air pulsed positive streamer discharges are generated in a 13 mm point-plane gap in the temperature range of 293 K-1136 K, and the effect of temperature on the streamer discharges is studied. When the temperature is increased, the product of applied voltage and temperature VT proportional to the reduced electric field can be used as a primary parameter that determines some discharge parameters regardless of temperature. For a given VT, the transferred charge per pulse, streamer diameter, product of discharge energy and temperature, and length of secondary streamer are almost constant regardless of T, whereas the streamer velocity decreases with increasing T and the decay rate of the discharge current is proportional to 1/T. The N2(C) emission intensity is approximately determined by the discharge energy independent of T. These results are useful to predict the streamer discharge and its reactive species production when the ambient temperature is increased.

  11. Variability of Winter Air Temperature in Mid-Latitude Europe

    NASA Technical Reports Server (NTRS)

    Otterman, J.; Ardizzone, J.; Atlas, R.; Bungato, D.; Cierniewski, J.; Jusem, J. C.; Przybylak, R.; Schubert, S.; Starr, D.; Walczewski, J.

    2002-01-01

    The aim of this paper is to report extreme winter/early-spring air temperature (hereinafter temperature) anomalies in mid-latitude Europe, and to discuss the underlying forcing to these interannual fluctuations. Warm advection from the North Atlantic in late winter controls the surface-air temperature, as indicated by the substantial correlation between the speed of the surface southwesterlies over the eastern North Atlantic (quantified by a specific Index Ina) and the 2-meter level air temperatures (hereinafter Ts) over Europe, 45-60 deg N, in winter. In mid-March and subsequently, the correlation drops drastically (quite often it is negative). This change in the relationship between Ts and Ina marks a transition in the control of the surface-air temperature: absorption of insolation replaces the warm advection as the dominant control. This forcing by maritime-air advection in winter was demonstrated in a previous publication, and is re-examined here in conjunction with extreme fluctuations of temperatures in Europe. We analyze here the interannual variability at its extreme by comparing warm-winter/early-spring of 1989/90 with the opposite scenario in 1995/96. For these two December-to-March periods the differences in the monthly mean temperature in Warsaw and Torun, Poland, range above 10 C. Short-term (shorter than a month) fluctuations of the temperature are likewise very strong. We conduct pentad-by-pentad analysis of the surface-maximum air temperature (hereinafter Tmax), in a selected location, examining the dependence on Ina. The increased cloudiness and higher amounts of total precipitable water, corollary effects to the warm low-level advection. in the 1989/90 winter, enhance the positive temperature anomalies. The analysis of the ocean surface winds is based on the Special Sensor Microwave/Imager (SSM/I) dataset; ascent rates, and over land wind data are from the European Centre for Medium-Range Weather Forecasts (ECMWF); maps of 2-m temperature, cloud

  12. Global surface air temperatures - Update through 1987

    NASA Technical Reports Server (NTRS)

    Hansen, James; Lebedeff, Sergej

    1988-01-01

    Data from meteorological stations show that surface air temperatures in the 1980s are the warmest in the history of instrumental records. The four warmest years on record are all in the 1980s, with the warmest years in the analysis being 1981 and 1987. The rate of warming between the mid-1960s and the present is higher than that which occurrred in the previous period of rapid warming between the 1880s and 1940.

  13. Global trends of measured surface air temperature

    NASA Technical Reports Server (NTRS)

    Hansen, James; Lebedeff, Sergej

    1987-01-01

    The paper presents the results of surface air temperature measurements from available meteorological stations for the period of 1880-1985. It is shown that the network of meteorological stations is sufficient to yield reliable long-term, decadal, and interannual temperature changes for both the Northern Hemisphere and the Southern Hemisphere, despite the fact that most stations are located on the continents. The results indicate a global warming of about 0.5-0.7 C in the past century, with warming of similar magnitude in both hemispheres. A strong warming trend between 1965 and 1980 raised the global mean temperature in 1980 and 1981 to the highest level in the period of instrumental records. Selected graphs of the temperature change in each of the eight latitude zones are included.

  14. Temperature Dependence of Lithium Reactions with Air

    NASA Astrophysics Data System (ADS)

    Sherrod, Roman; Skinner, C. H.; Koel, Bruce

    2016-10-01

    Liquid lithium plasma facing components (PFCs) are being developed to handle long pulse, high heat loads in tokamaks. Wetting by lithium of its container is essential for this application, but can be hindered by lithium oxidation by residual gases or during tokamak maintenance. Lithium PFCs will experience elevated temperatures due to plasma heat flux. This work presents measurements of lithium reactions at elevated temperatures (298-373 K) when exposed to natural air. Cylindrical TZM wells 300 microns deep with 1 cm2 surface area were filled with metallic lithium in a glovebox containing argon with less than 1.6 ppm H20, O2, and N2. The wells were transferred to a hot plate in air, and then removed periodically for mass gain measurements. Changes in the surface topography were recorded with a microscope. The mass gain of the samples at elevated temperatures followed a markedly different behavior to that at room temperature. One sample at 373 K began turning red indicative of lithium nitride, while a second turned white indicative of lithium carbonate formation. Data on the mass gain vs. temperature and associated topographic changes of the surface will be presented. Science Undergraduate Laboratory Internship funded by Department of Energy.

  15. Assessment of two-temperature kinetic model for ionizing air

    NASA Technical Reports Server (NTRS)

    Park, Chul

    1987-01-01

    A two-temperature chemical-kinetic model for air is assessed by comparing theoretical results with existing experimental data obtained in shock-tubes, ballistic ranges, and flight experiments. In the model, named the TTv model, one temperature (T) is assumed to characterize the heavy-particle translational and molecular rotational energies, and another temperature (Tv) to characterize the molecular vibrational, electron translational, and electronic excitation energies. The theoretical results for nonequilibrium air flow in shock tubes are obtained using the computer code STRAP (Shock-Tube Radiation Program), and for flow along the stagnation streamline in the shock layer over spherical bodies using the newly developed code STRAP (Stagnation-Point Radiation Program). Substantial agreement is shown between the theoretical and experimental results for relaxation times and radiative heat fluxes. At very high temperatures the spectral calculations need further improvement. The present agreement provides strong evidence that the two-temperature model characterizes principal features of nonequilibrium air flow. New theoretical results using the model are presented for the radiative heat fluxes at the stagnation point of a 6-m-radius sphere, representing an aeroassisted orbital transfer vehicle, over a range of free-stream conditions. Assumptions, approximations, and limitations of the model are discussed.

  16. Flame Speeds of Methane-Air, Propane-Air, and Ethylene-Air Mixtures at Low Initial Temperatures

    NASA Technical Reports Server (NTRS)

    Dugger, Gordon L; Heimel, Sheldon

    1952-01-01

    Flame speeds were determined for methane-air, propane-air, and ethylene-air mixtures at -73 C and for methane-air mixtures at -132 C. The data extend the curves of maximum flame speed against initial mixture temperature previously established for the range from room temperature to 344 C. Empirical equations for maximum flame speed u(cm/ sec) as a function of initial mixture temperature T(sub O) were determined to be as follows: for methane, for T(sub O) from 141 to 615 K, u = 8 + 0.000160 T(sub O)(exp 2.11); for propane, for T(sub O) from 200 to 616 K, u = 10 + 0.000342 T(sub O)(exp 2.00); for ethylene, for T(sub O) from 200 to 617 K, u = 10 + 0.00259 T(sub O)(exp 1.74). Relative flame speeds at low initial temperatures were predicted within approximately 20 percent by either the thermal theory as presented by Semenov or by the diffusion theory of Tanford and Pease. The same order was found previously for high initial temperatures. The low-temperature data were also found to extend the linear correlations between maximum flame speed and calculated equilibrium active-radical concentrations, which were established by the previously reported high-temperature data.

  17. 33 CFR 334.700 - Choctawhatchee Bay, aerial gunnery ranges, Air Armament Center, Eglin Air Force Base, Fla.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... gunnery ranges, Air Armament Center, Eglin Air Force Base, Fla. 334.700 Section 334.700 Navigation and... RESTRICTED AREA REGULATIONS § 334.700 Choctawhatchee Bay, aerial gunnery ranges, Air Armament Center, Eglin Air Force Base, Fla. (a) The danger zones—(1) Aerial gunnery range in west part of Choctawhatchee...

  18. 33 CFR 334.700 - Choctawhatchee Bay, aerial gunnery ranges, Air Armament Center, Eglin Air Force Base, Fla.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... gunnery ranges, Air Armament Center, Eglin Air Force Base, Fla. 334.700 Section 334.700 Navigation and... RESTRICTED AREA REGULATIONS § 334.700 Choctawhatchee Bay, aerial gunnery ranges, Air Armament Center, Eglin Air Force Base, Fla. (a) The danger zones—(1) Aerial gunnery range in west part of Choctawhatchee...

  19. 33 CFR 334.700 - Choctawhatchee Bay, aerial gunnery ranges, Air Armament Center, Eglin Air Force Base, Fla.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... gunnery ranges, Air Armament Center, Eglin Air Force Base, Fla. 334.700 Section 334.700 Navigation and... RESTRICTED AREA REGULATIONS § 334.700 Choctawhatchee Bay, aerial gunnery ranges, Air Armament Center, Eglin Air Force Base, Fla. (a) The danger zones—(1) Aerial gunnery range in west part of Choctawhatchee...

  20. Advances in Fast Response Acoustically Derived Air Temperature Measurements

    NASA Astrophysics Data System (ADS)

    Bogoev, Ivan; Jacobsen, Larry; Horst, Thomas; Conrad, Benjamin

    2016-04-01

    Fast-response accurate air-temperature measurements are required when estimating turbulent fluxes of heat, water and carbon dioxide by open-path eddy-covariance technique. In comparison with contact thermometers like thermocouples, ultra-sonic thermometers do not suffer from solar radiation loading, water vapor condensation and evaporative cooling effects. Consequently they have the potential to provide more accurate true air temperature measurements. The absolute accuracy of the ultrasonic thermometer is limited by the following parameters: the distance between the transducer pairs, transducer delays associated with the electrical-acoustic signal conversion that vary with temperature, components of the wind vector that are normal to the ultrasonic paths, and humidity. The distance between the transducer pairs is commonly obtained by coordinate measuring machine. Improved accuracy demonstrated in this study results from increased stiffness in the anemometer head to better maintain the ultrasonic path-length distances. To further improve accuracy and account for changes in transducer delays and distance as a function of temperature, these parameters are characterized in a zero-wind chamber over the entire operating temperature range. When the sonic anemometer is combined with a co-located fast-response water vapor analyzer, like in the IRGASON instrument, speed of sound can be compensated for humidity effects on a point-by-point basis resulting in a true fast-response air temperature measurement. Laboratory test results show that when the above steps are implemented in the calibration of the ultrasonic thermometer air-temperature accuracy better than ±0.5 degrees Celsius can be achieved over the entire operating range. The approach is also validated in a field inter-comparison with an aspirated thermistor probe mounted in a radiation shield.

  1. Trends in Surface Temperature from AIRS.

    NASA Astrophysics Data System (ADS)

    Ruzmaikin, A.; Aumann, H. H.

    2014-12-01

    To address possible causes of the current hiatus in the Earth's global temperature we investigate the trends and variability in the surface temperature using retrievals obtained from the measurements by the Atmospheric Infrared Sounder (AIRS) and its companion instrument, the Advanced Microwave Sounding Unit (AMSU), onboard of Aqua spacecraft in 2002-2014. The data used are L3 monthly means on a 1x1degree spatial grid. We separate the land and ocean temperatures, as well as temperatures in Artic, Antarctic and desert regions. We find a monotonic positive trend for the land temperature but not for the ocean temperature. The difference in the regional trends can help to explain why the global surface temperature remains almost unchanged but the frequency of occurrence of the extreme events increases under rising anthropogenic forcing. The results are compared with the model studies. This work was supported by the Jet Propulsion Laboratory of the California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

  2. Requirements for high-temperature air-cooled central receivers

    NASA Astrophysics Data System (ADS)

    Wright, J. D.; Copeland, R. J.

    1983-12-01

    The design of solar thermal central receivers will be shaped by the end user's need for energy. This paper identifies the requirements for receivers supplying heat for industrial processes or electric power generation in the temperature range 540 to 1000(0)C and evaluates the effects of the requirements on air cooled central receivers. Potential IPH applications are identified as large baseload users that are located some distance from the receiver. In the electric power application, the receiver must supply heat to a pressurized gas power cycle. The difficulty in providing cost effective thermal transport and thermal storage for air cooled receivers is a critical problem.

  3. Can air temperature be used to project influences of climate change on stream temperature?

    USGS Publications Warehouse

    Arismendi, Ivan; Safeeq, Mohammad; Dunham, Jason B.; Johnson, Sherri L.

    2014-01-01

    Worldwide, lack of data on stream temperature has motivated the use of regression-based statistical models to predict stream temperatures based on more widely available data on air temperatures. Such models have been widely applied to project responses of stream temperatures under climate change, but the performance of these models has not been fully evaluated. To address this knowledge gap, we examined the performance of two widely used linear and nonlinear regression models that predict stream temperatures based on air temperatures. We evaluated model performance and temporal stability of model parameters in a suite of regulated and unregulated streams with 11–44 years of stream temperature data. Although such models may have validity when predicting stream temperatures within the span of time that corresponds to the data used to develop them, model predictions did not transfer well to other time periods. Validation of model predictions of most recent stream temperatures, based on air temperature–stream temperature relationships from previous time periods often showed poor performance when compared with observed stream temperatures. Overall, model predictions were less robust in regulated streams and they frequently failed in detecting the coldest and warmest temperatures within all sites. In many cases, the magnitude of errors in these predictions falls within a range that equals or exceeds the magnitude of future projections of climate-related changes in stream temperatures reported for the region we studied (between 0.5 and 3.0 °C by 2080). The limited ability of regression-based statistical models to accurately project stream temperatures over time likely stems from the fact that underlying processes at play, namely the heat budgets of air and water, are distinctive in each medium and vary among localities and through time.

  4. Is Air Temperature Enough to Predict Lake Surface Temperature?

    NASA Astrophysics Data System (ADS)

    Piccolroaz, S.; Toffolon, M.; Majone, B.

    2014-12-01

    Lake surface water (LST) is a key factor that controls most of the physical and ecological processes occurring in lakes. Reliable estimates are especially important in the light of recent studies, which revealed that inland water bodies are highly sensitive to climate, and are rapidly warming throughout the world. However, an accurate estimation of LST usually requires a significant amount of information that is not always available. In this work, we present an application of air2water, a lumped model that simulates LST as a function of air temperature only. In addition, air2water allows for a qualitative evaluation of the depth of the epilimnion during the annual stratification cycle. The model consists in a simplification of the complete heat budget of the well-mixed surface layer, and has a few parameters (from 4 to 8 depending on the version) that summarize the role of the different heat flux components. Model calibration requires only air and water temperature data, possibly covering sufficiently long historical periods in order to capture inter-annual variability and long-term trends. During the calibration procedure, the information included in input data is retrieved to directly inform model parameters, which can be used to classify the thermal behavior of the lake. In order to investigate how thermal dynamics are related to morphological features, the model has been applied to 14 temperate lakes characterized by different morphological and hydrological conditions, by different sources of temperature data (buoys, satellite), and by variable frequency of acquisition. A good agreement between observed and simulated LST has been achieved, with a RMSE in the order of 1°C, which is fully comparable to the performances of more complex process-based models. This application allowed for a deeper understanding of the thermal response of lakes as a function of their morphology, as well as for specific analyses as for example the investigation of the exceptional

  5. Impacts of the Convention on Long-range Transboundary Air Pollution on air quality in Europe.

    PubMed

    Bull, Keith; Johansson, Matti; Krzyzanowski, Michal

    2008-01-01

    The Convention on Long-range Transboundary Air Pollution has been one of the main ways of protecting the environment in Europe from air pollution. This convention has successfully bridged different political systems even through times of political change, and is a prime example of what can be achieved through intergovernmental cooperation. Through creating an effective framework for controlling and reducing the damage to human health and the environment from transboundary air pollution, this convention has proved successful. This article considers the development of the convention and its work on adverse air pollution effects, in particular on activities related to quantifying effects on human health as carried out by the convention's joint (with WHO) Task Force on the Health Effects of Air Pollution (Task Force on Health), and concludes with some indications of the convention's future priorities.

  6. The complex kinetics of protein folding in wide temperature ranges.

    PubMed

    Wang, Jin

    2004-10-01

    The complex protein folding kinetics in wide temperature ranges is studied through diffusive dynamics on the underlying energy landscape. The well-known kinetic chevron rollover behavior is recovered from the mean first passage time, with the U-shape dependence on temperature. The fastest folding temperature T0 is found to be smaller than the folding transition temperature Tf. We found that the fluctuations of the kinetics through the distribution of first passage time show rather universal behavior, from high-temperature exponential Poissonian kinetics to the relatively low-temperature highly non-exponential kinetics. The transition temperature is at Tk and T0 < Tk < Tf. In certain low-temperature regimes, a power law behavior at long time emerges. At very low temperatures (lower than trapping transition temperature T < T0/(4 approximately 6)), the kinetics is an exponential Poissonian process again.

  7. 14 CFR 23.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Carburetor air temperature controls. 23... Powerplant Powerplant Controls and Accessories § 23.1157 Carburetor air temperature controls. There must be a separate carburetor air temperature control for each engine....

  8. 14 CFR 23.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Carburetor air temperature controls. 23... Powerplant Powerplant Controls and Accessories § 23.1157 Carburetor air temperature controls. There must be a separate carburetor air temperature control for each engine....

  9. 40 CFR 89.325 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made...

  10. 40 CFR 89.325 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made...

  11. 14 CFR 23.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Carburetor air temperature controls. 23... Powerplant Powerplant Controls and Accessories § 23.1157 Carburetor air temperature controls. There must be a separate carburetor air temperature control for each engine....

  12. 40 CFR 89.325 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made...

  13. 14 CFR 23.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Carburetor air temperature controls. 23... Powerplant Powerplant Controls and Accessories § 23.1157 Carburetor air temperature controls. There must be a separate carburetor air temperature control for each engine....

  14. 14 CFR 23.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Carburetor air temperature controls. 23... Powerplant Powerplant Controls and Accessories § 23.1157 Carburetor air temperature controls. There must be a separate carburetor air temperature control for each engine....

  15. 40 CFR 89.325 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made...

  16. Historical Air Temperatures Across the Hawaiian Islands

    NASA Astrophysics Data System (ADS)

    Kagawa-Viviani, A.; Giambelluca, T. W.

    2015-12-01

    This study focuses on an analysis of daily temperature from over 290 ground-based stations across the Hawaiian Islands from 1905-2015. Data from multiple stations were used to model environmental lapse rates by fitting linear regressions of mean daily Tmax and Tmin on altitude; piecewise regressions were also used to model the discontinuity introduced by the trade wind inversion near 2150m. Resulting time series of both model coefficients and lapse rates indicate increasing air temperatures near sea level (Tmax: 0.09°C·decade-1 and Tmin: 0.23°C·decade-1 over the most recent 65 years). Evaluation of lapse rates during this period suggest Tmax lapse rates (~0.6°C·100m-1) are decreasing by 0.006°C·100m-1decade-1 due to rapid high elevation warming while Tmin lapse rates (~0.8°C·100m-1) are increasing by 0.002°C·100m-1decade-1 due to the stronger increase in Tmin at sea level versus at high elevation. Over the 110 year period, temperatures tend to vary coherently with the PDO index. Our analysis verifies warming trends and temperature variability identified earlier by analysis of selected index stations. This method also provides temperature time series we propose are more robust to station inhomogeneities.

  17. The mass and speed dependence of meteor air plasma temperatures

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Laux, Christophe O.; Wilson, Michael A.; Schaller, Emily L.

    2004-01-01

    The speed and mass dependence of meteor air plasma temperatures is perhaps the most important data needed to understand how small meteoroids chemically change the ambient atmosphere in their path and enrich the ablated meteoric organic matter with oxygen. Such chemistry can play an important role in creating prebiotic compounds. The excitation conditions in various air plasma emissions were measured from high-resolution optical spectra of Leonid storm meteors during NASA's Leonid Multi-Instrument Aircraft Campaign. This was the first time a sufficient number and range of temperature measurements were obtained to search for meteoroid mass and speed dependencies. We found slight increases in temperature with decreasing altitude, but otherwise nearly constant values for meteoroids with speeds between 35 and 72 km/s and masses between 10(-5) g and 1 g. We conclude that faster and more massive meteoroids produce a larger emission volume, but not a higher air plasma temperature. We speculate that the meteoric plasma may be in multiphase equilibrium with the ambient atmosphere, which could mean lower plasma temperatures in a CO(2)-rich early Earth atmosphere.

  18. The mass and speed dependence of meteor air plasma temperatures.

    PubMed

    Jenniskens, Peter; Laux, Christophe O; Wilson, Michael A; Schaller, Emily L

    2004-01-01

    The speed and mass dependence of meteor air plasma temperatures is perhaps the most important data needed to understand how small meteoroids chemically change the ambient atmosphere in their path and enrich the ablated meteoric organic matter with oxygen. Such chemistry can play an important role in creating prebiotic compounds. The excitation conditions in various air plasma emissions were measured from high-resolution optical spectra of Leonid storm meteors during NASA's Leonid Multi-Instrument Aircraft Campaign. This was the first time a sufficient number and range of temperature measurements were obtained to search for meteoroid mass and speed dependencies. We found slight increases in temperature with decreasing altitude, but otherwise nearly constant values for meteoroids with speeds between 35 and 72 km/s and masses between 10(-5) g and 1 g. We conclude that faster and more massive meteoroids produce a larger emission volume, but not a higher air plasma temperature. We speculate that the meteoric plasma may be in multiphase equilibrium with the ambient atmosphere, which could mean lower plasma temperatures in a CO(2)-rich early Earth atmosphere.

  19. Soil moisture sensing with aircraft observations of the diurnal range of surface temperature

    NASA Technical Reports Server (NTRS)

    Schmugge, T. J.; Blanchard, B.; Anderson, A.; Wang, V.

    1977-01-01

    Aircraft observations of the surface temperature were made by measurements of the thermal emission in the 8-14 micrometers band over agricultural fields around Phoenix, Arizona. The diurnal range of these surface temperature measurements were well correlated with the ground measurement of soil moisture in the 0-2 cm layer. The surface temperature observations for vegetated fields were found to be within 1 or 2 C of the ambient air temperature indicating no moisture stress. These results indicate that for clear atmospheric conditions remotely sensed surface temperatures are a reliable indicator of soil moisture conditions and crop status.

  20. Temperature inversion in long-range interacting systems.

    PubMed

    Teles, Tarcísio N; Gupta, Shamik; Di Cintio, Pierfrancesco; Casetti, Lapo

    2015-08-01

    Temperature inversions occur in nature, e.g., in the solar corona and in interstellar molecular clouds: Somewhat counterintuitively, denser parts of the system are colder than dilute ones. We propose a simple and appealing way to spontaneously generate temperature inversions in systems with long-range interactions, by preparing them in inhomogeneous thermal equilibrium states and then applying an impulsive perturbation. In similar situations, short-range systems would typically relax to another thermal equilibrium, with a uniform temperature profile. By contrast, in long-range systems, the interplay between wave-particle interaction and spatial inhomogeneity drives the system to nonequilibrium stationary states that generically exhibit temperature inversion. We demonstrate this mechanism in a simple mean-field model and in a two-dimensional self-gravitating system. Our work underlines the crucial role the range of interparticle interaction plays in determining the nature of steady states out of thermal equilibrium.

  1. Diel Surface Temperature Range Scales with Lake Size

    PubMed Central

    Woolway, R. Iestyn; Jones, Ian D.; Maberly, Stephen C.; French, Jon R.; Livingstone, David M.; Monteith, Donald T.; Simpson, Gavin L.; Thackeray, Stephen J.; Andersen, Mikkel R.; Battarbee, Richard W.; DeGasperi, Curtis L.; Evans, Christopher D.; de Eyto, Elvira; Feuchtmayr, Heidrun; Hamilton, David P.; Kernan, Martin; Krokowski, Jan; Rimmer, Alon; Rose, Kevin C.; Rusak, James A.; Ryves, David B.; Scott, Daniel R.; Shilland, Ewan M.; Smyth, Robyn L.; Staehr, Peter A.; Thomas, Rhian; Waldron, Susan; Weyhenmeyer, Gesa A.

    2016-01-01

    Ecological and biogeochemical processes in lakes are strongly dependent upon water temperature. Long-term surface warming of many lakes is unequivocal, but little is known about the comparative magnitude of temperature variation at diel timescales, due to a lack of appropriately resolved data. Here we quantify the pattern and magnitude of diel temperature variability of surface waters using high-frequency data from 100 lakes. We show that the near-surface diel temperature range can be substantial in summer relative to long-term change and, for lakes smaller than 3 km2, increases sharply and predictably with decreasing lake area. Most small lakes included in this study experience average summer diel ranges in their near-surface temperatures of between 4 and 7°C. Large diel temperature fluctuations in the majority of lakes undoubtedly influence their structure, function and role in biogeochemical cycles, but the full implications remain largely unexplored. PMID:27023200

  2. Diel Surface Temperature Range Scales with Lake Size.

    PubMed

    Woolway, R Iestyn; Jones, Ian D; Maberly, Stephen C; French, Jon R; Livingstone, David M; Monteith, Donald T; Simpson, Gavin L; Thackeray, Stephen J; Andersen, Mikkel R; Battarbee, Richard W; DeGasperi, Curtis L; Evans, Christopher D; de Eyto, Elvira; Feuchtmayr, Heidrun; Hamilton, David P; Kernan, Martin; Krokowski, Jan; Rimmer, Alon; Rose, Kevin C; Rusak, James A; Ryves, David B; Scott, Daniel R; Shilland, Ewan M; Smyth, Robyn L; Staehr, Peter A; Thomas, Rhian; Waldron, Susan; Weyhenmeyer, Gesa A

    2016-01-01

    Ecological and biogeochemical processes in lakes are strongly dependent upon water temperature. Long-term surface warming of many lakes is unequivocal, but little is known about the comparative magnitude of temperature variation at diel timescales, due to a lack of appropriately resolved data. Here we quantify the pattern and magnitude of diel temperature variability of surface waters using high-frequency data from 100 lakes. We show that the near-surface diel temperature range can be substantial in summer relative to long-term change and, for lakes smaller than 3 km2, increases sharply and predictably with decreasing lake area. Most small lakes included in this study experience average summer diel ranges in their near-surface temperatures of between 4 and 7°C. Large diel temperature fluctuations in the majority of lakes undoubtedly influence their structure, function and role in biogeochemical cycles, but the full implications remain largely unexplored.

  3. Braze alloy holds bonding strength over wide temperature range

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Copper-based quaternary alloys of the solid solution type is used for vacuum furnace brazing of large stainless steel components at a maximum temperature of 1975 deg F. The alloy has high bonding strength and good ductility over a temperature range extending from the cryogenic region to approximately 800 deg F.

  4. Thermodynamics of Quantum Gases for the Entire Range of Temperature

    ERIC Educational Resources Information Center

    Biswas, Shyamal; Jana, Debnarayan

    2012-01-01

    We have analytically explored the thermodynamics of free Bose and Fermi gases for the entire range of temperature, and have extended the same for harmonically trapped cases. We have obtained approximate chemical potentials for the quantum gases in closed forms of temperature so that the thermodynamic properties of the quantum gases become…

  5. Study of Ram-air Heat Exchangers for Reducing Turbine Cooling-air Temperature of a Supersonic Aircraft Turbojet Engine

    NASA Technical Reports Server (NTRS)

    Diaguila, Anthony J; Livingood, John N B; Eckert, Ernst R G

    1956-01-01

    The sizes and weights of the cores of heat exchangers were determined analytically for possible application for reducing turbine cooling-air temperatures of an engine designed for a Mach number of 2.5 and an altitude The sizes and weights of the cores of heat exchangers were determined analytically for possible application for reducing turbine cooling-air temperatures of an engine designed for a Mach number of 2.5 and an altitude of 70,000 feet. A compressor-bleed-air weight flow of 2.7 pounds per second was assumed for the coolant; ram air was considered as the other fluid. Pressure drops and inlet states of both fluids were prescribed, and ranges of compressor-bleed-air temperature reductions and of the ratio of compressor-bleed to ram-air weight flows were considered.

  6. Evidence of Lunar Phase Influence on Global Surface Air Temperatures

    NASA Technical Reports Server (NTRS)

    Anyamba, Ebby; Susskind, Joel

    2000-01-01

    Intraseasonal oscillations appearing in a newly available 20-year record of satellite-derived surface air temperature are composited with respect to the lunar phase. Polar regions exhibit strong lunar phase modulation with higher temperatures occurs near full moon and lower temperatures at new moon, in agreement with previous studies. The polar response to the apparent lunar forcing is shown to be most robust in the winter months when solar influence is minimum. In addition, the response appears to be influenced by ENSO events. The highest mean temperature range between full moon and new moon in the polar region between 60 deg and 90 deg latitude was recorded in 1983, 1986/87, and 1990/91. Although the largest lunar phase signal is in the polar regions, there is a tendency for meridional equatorward progression of anomalies in both hemispheres so that the warning in the tropics occurs at the time of the new moon.

  7. Measuring Systems for Thermometer Calibration in Low-Temperature Range

    NASA Astrophysics Data System (ADS)

    Szmyrka-Grzebyk, A.; Lipiński, L.; Manuszkiewicz, H.; Kowal, A.; Grykałowska, A.; Jancewicz, D.

    2011-12-01

    The national temperature standard for the low-temperature range between 13.8033 K and 273.16 K has been established in Poland at the Institute of Low Temperature and Structure Research (INTiBS). The standard consists of sealed cells for realization of six fixed points of the International Temperature Scale of 1990 (ITS-90) in the low-temperature range, an adiabatic cryostat and Isotech water and mercury triple-point baths, capsule standard resistance thermometers (CSPRT), and AC and DC bridges with standard resistors for thermometers resistance measurements. INTiBS calibrates CSPRTs at the low-temperature fixed points with uncertainties less than 1 mK. In lower temperature range—between 2.5 K and about 25 K — rhodium-iron (RhFe) resistance thermometers are calibrated by comparison with a standard which participated in the EURAMET.T-K1.1 comparison. INTiBS offers a calibration service for industrial platinum resistance thermometers and for digital thermometers between 77 K and 273 K. These types of thermometers may be calibrated at INTiBS also in a higher temperature range up to 550°C. The Laboratory of Temperature Standard at INTiBS acquired an accreditation from the Polish Centre for Accreditation. A management system according to EN ISO/IEC 17025:2005 was established at the Laboratory and presented on EURAMET QSM Forum.

  8. Silicon device performance measurements to support temperature range enhancement

    NASA Technical Reports Server (NTRS)

    Bromstead, James; Weir, Bennett; Johnson, R. Wayne; Askew, Ray

    1991-01-01

    Semiconductor power devices are typically rated for operation below 150 C. Little data is known for power semiconductors over 150 C. In most cases, the device is derated to zero operating power at 175 C. At the high temperature end of the temperature range, the intrinsic carrier concentration increases to equal the doping concentration level and the silicon behaves as an intrinsic semiconductor. The increase in intrinsic carrier concentration results in a shift of the Fermi level toward mid-bandgap at elevated temperatures. This produces a shift in devices characteristics as a function of temperature. By increasing the doping concentration higher operating temperatures can be achieved. This technique was used to fabricate low power analog and digital devices in silicon with junction operating temperatures in excess of 300 C. Additional temperature effects include increased p-n junction leakage with increasing temperature, resulting in increased resistivity. The temperature dependency of physical properties results in variations in device characteristics. These must be quantified and understood in order to develop extended temperature range operation.

  9. 14 CFR 25.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Carburetor air temperature controls. 25.1157 Section 25.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 25.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  10. 14 CFR 29.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Carburetor air temperature controls. 29.1157 Section 29.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 29.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  11. 14 CFR 29.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Carburetor air temperature controls. 29.1157 Section 29.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 29.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  12. 14 CFR 25.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Carburetor air temperature controls. 25.1157 Section 25.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 25.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  13. 14 CFR 25.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Carburetor air temperature controls. 25.1157 Section 25.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 25.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  14. 14 CFR 25.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Carburetor air temperature controls. 25.1157 Section 25.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 25.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  15. 14 CFR 29.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Carburetor air temperature controls. 29.1157 Section 29.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 29.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  16. 14 CFR 29.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Carburetor air temperature controls. 29.1157 Section 29.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 29.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  17. 14 CFR 29.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Carburetor air temperature controls. 29.1157 Section 29.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 29.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  18. 14 CFR 25.1157 - Carburetor air temperature controls.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Carburetor air temperature controls. 25.1157 Section 25.1157 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Accessories § 25.1157 Carburetor air temperature controls. There must be a separate carburetor air...

  19. Air temperature variation across the seed cotton dryer mixpoint

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eighteen tests were conducted in six gins in the fall of 2008 to measure air temperature variation within various heated air seed cotton drying systems with the purpose of: checking validation of recommendations by a professional engineering society and measuring air temperature variation across the...

  20. AIR TEMPERATURE DISTRIBUTION IN SEED COTTON DRYING SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ten tests were conducted in the fall of 2007 to measure air temperature variation within various heated air seed cotton drying systems with the purpose of: checking validation of recommendations by a professional engineering society and measuring air temperature variation across the airflow ductwork...

  1. Possible Economies in Air-Conditioning by Accepting Temperature Swings.

    ERIC Educational Resources Information Center

    Loudon, A. G.; Petherbridge, P.

    Public building air conditioning systems, which use constant and varying heat and cooling loads, are compared and investigated. Experiments indicated that constant temperature controls based on outside air temperature alone were inefficient. Ventilating a building with outside air and the methods of doing so are cited as being the most economical…

  2. Compression-ignition Engine Performance at Altitudes and at Various Air Pressures and Temperatures

    NASA Technical Reports Server (NTRS)

    Moore, Charles S; Collins, John H

    1937-01-01

    Engine test results are presented for simulated altitude conditions. A displaced-piston combustion chamber on a 5- by 7-inch single cylinder compression-ignition engine operating at 2,000 r.p.m. was used. Inlet air temperature equivalent to standard altitudes up to 14,000 feet were obtained. Comparison between performance at altitude of the unsupercharged compression-ignition engine compared favorably with the carburetor engine. Analysis of the results for which the inlet air temperature, inlet air pressure, and inlet and exhaust pressure were varied indicates that engine performance cannot be reliably corrected on the basis of inlet air density or weight of air charge. Engine power increases with inlet air pressure and decreases with inlet air temperatures very nearly as straight line relations over a wide range of air-fuel ratios. Correction factors are given.

  3. Faraday isolator stably operating in a wide temperature range

    NASA Astrophysics Data System (ADS)

    Mironov, E. A.; Voitovich, A. V.; Palashov, O. V.

    2016-03-01

    A method of stabilizing Faraday isolator characteristics at varying temperatures is proposed in this letter. The method is based on the use of a magnetic system with an inhomogeneous magnetic field and a magneto-optical element holder made of a material with a high value of thermal expansion coefficient. Changing the rotation angle of the polarization plane of radiation caused by the temperature variation of the magneto-optical element and the temperature dependence of its Verdet constant is compensated by its shifting in the magnetic field. The developed device demonstrates an isolation ratio of more than 40 dB at a temperature range of 25 °C. Estimates show the possibility of providing an isolation ratio of more than 45 dB in a temperature range of 60 °C.

  4. [Temperature range for growth of the Antarctic microorganisms].

    PubMed

    Romanovaskaia, V A; Tashirev, A B; Gladka, G B; Tashireva, A A

    2012-01-01

    The assessment of a temperature range for growth of microorganisms isolated at various temperatures (1-5 degrees C or 30 degrees C) from biotopes of the Antarctic region (soil, grass Deschampcia antarctica, grass Colobanthus, a green moss, crustose black lichens and encrustation biofilm on vertical rocks) is made. From 40 to 70% of the investigated Antarctic microorganisms, irrespective of temperature conditions of their isolation, were capable of growing in a wide temperature range (from 1 degrees C to 30 degrees C), i.e. they are psychrotolerant. In selective conditions (1 degrees C or 5 degrees C) the psychrophilic Antarctic bacteria and yeast are isolated which grew in the range from 1 degrees C to 20 degrees C and did not grow at 30 degrees C. At the same time, among the Antarctic microorganisms isolated in nonselective conditions (at 30 degrees C), almost 50% are capable of growing at the lowest temperature (5 degrees C), and a smaller number of strains--at 1 degrees C. However with a decrease of cultivation temperature the growth lag-phase of the Antarctic bacteria increased. Thus the level of the final biomass of the investigated strains did not depend on cultivation temperature. When comparing the temperature range of growth of the mesophilic Antarctic bacteria and collection strains of the same species isolated more than 10 years ago from the region with a temperate climate, the psychrotolerant forms were also revealed among the latter. So, it is shown that the investigated Antarctic bacteria can exist in the temperature range characteristic of terrestrial biotopes of the Antarctic Region (from 1 degrees C to 10 degrees C).

  5. Improved Wide Operating Temperature Range of Li-Ion Cells

    NASA Technical Reports Server (NTRS)

    Smart, Marshall C.; Bugga, Ratnakumar V.

    2013-01-01

    Future NASA missions aimed at exploring the Moon, Mars, and the outer planets require rechargeable batteries that can operate over a wide temperature range (-60 to +60 C) to satisfy the requirements of various applications including landers, rovers, penetrators, CEV, CLV, etc. This work addresses the need for robust rechargeable batteries that can operate well over a wide temperature range. The Department of Energy (DoE) has identified a number of technical barriers associated with the development of Liion rechargeable batteries for PHEVs. For this reason, DoE has interest in the development of advanced electrolytes that will improve performance over a wide range of temperatures, and lead to long life characteristics (5,000 cycles over a 10-year life span). There is also interest in improving the high-voltage stability of these candidate electrolyte systems to enable the operation of up to 5 V with high specific energy cathode materials. Currently, the state-of-the-art lithium-ion system has been demonstrated to operate over a wide range of temperatures (-40 to +40 C); however, the rate capability at the lower temperatures is very poor. In addition, the low-temperature performance typically deteriorates rapidly upon being exposed to high temperatures. A number of electrolyte formulations were developed that incorporate the use of electrolyte additives to improve the high-temperature resilience, low-temperature power capability, and life characteristics of methyl propionate (MP)-based electrolyte solutions. These electrolyte additives include mono-fluoroethylene carbonate (FEC), lithium oxalate, vinylene carbonate (VC), and lithium bis(oxalate borate) (LiBOB), which have previously been shown to result in improved high-temperature resilience of all carbonate-based electrolytes. These MP-based electrolytes with additives have been shown to have improved performance in experiments with MCMB-LiNiCoAlO2 cells.

  6. Sensitivity of New England Stream Temperatures to Air Temperature and Precipitation Under Projected Climate

    NASA Astrophysics Data System (ADS)

    Huang, T.; Samal, N. R.; Wollheim, W. M.; Stewart, R. J.; Zuidema, S.; Prousevitch, A.; Glidden, S.

    2015-12-01

    The thermal response of streams and rivers to changing climate will influence aquatic habitat. This study examines the impact that changing climate has on stream temperatures in the Merrimack River, NH/MA USA using the Framework for Aquatic Modeling in the Earth System (FrAMES), a spatially distributed river network model driven by air temperature, air humidity, wind speed, precipitation, and solar radiation. Streamflow and water temperatures are simulated at a 45-second (latitude x longitude) river grid resolution for 135 years under historical and projected climate variability. Contemporary streamflow (Nash-Sutcliffe Coefficient = 0.77) and river temperatures (Nash-Sutcliffe Coefficient = 0.89) matched at downstream USGS gauge data well. A suite of model runs were made in combination with uniformly increased daily summer air temperatures by 2oC, 4 oC and 6 oC as well as adjusted precipitation by -40%, -30%, -20%, -10% and +10% as a sensitivity analysis to explore a broad range of potential future climates. We analyzed the summer stream temperatures and the percent of river length unsuitable for cold to warm water fish habitats. Impacts are greatest in large rivers due to the accumulation of river temperature warming throughout the entire river network. Cold water fish (i.e. brook trout) are most strongly affected while, warm water fish (i.e. largemouth bass) aren't expected to be impacted. The changes in stream temperatures under various potential climate scenarios will provide a better understanding of the specific impact that air temperature and precipitation have on aquatic thermal regimes and habitat.

  7. Transport properties of high-temperature air in a magnetic field

    SciTech Connect

    Bruno, D.; Capitelli, M.; Catalfamo, C.; Giordano, D.

    2011-01-15

    Transport properties of equilibrium air plasmas in a magnetic field are calculated with the Chapman-Enskog method. The range considered for the temperature is [50-50 000] K and for the magnetic induction is [0-300] T.

  8. Nylon coil actuator operating temperature range and stiffness

    NASA Astrophysics Data System (ADS)

    Kianzad, Soheil; Pandit, Milind; Bahi, Addie; Rafie Ravandi, Ali; Ko, Frank; Spinks, Geoffrey M.; Madden, John D. W.

    2015-04-01

    Components in automotive and aerospace applications require a wide temperature range of operation. Newly discovered thermally active Baughman muscle potentially provides affordable and viable solutions for driving mechanical devices by heating them from room temperature, but little is known about their operation below room temperature. We study the mechanical behavior of nylon coil actuators by testing elastic modulus and by investigating tensile stroke as a function of temperature. Loads that range from 35 MPa to 155 MPa were applied. For the nylon used and the coiling conditions, active thermal contraction totals 19.5 % when the temperature is raised from -40 °C to 160 °C. The thermal contraction observed from -40 °C to 20°C is only ~2 %, whereas between 100 and 160 °C the contraction is 10 %. A marked increase in thermal contraction is occurs in the vicinity of the glass transition temperature (~ 45°C). The elastic modulus drops as temperature increases, from ~155 MPa at - 40 °C to 35 MPa at 200 °C. Interestingly the drop in active contraction with increasing load is small and much less than might be expected given the temperature dependence of modulus.

  9. 40 CFR 90.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C....

  10. 40 CFR 90.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C....

  11. 40 CFR 90.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C....

  12. 40 CFR 90.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C....

  13. 33 CFR 334.490 - Atlantic Ocean off Georgia Coast; air-to-air and air-to-water gunnery and bombing ranges for...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., U.S. Air Force. (a) The danger zones—(1) For fighter aircraft. An area approximately 30 miles... Officer, 2d Bombardment Wing, Hunter Air Force Base, Savannah, Georgia, and such agencies as he may...; air-to-air and air-to-water gunnery and bombing ranges for fighter and bombardment aircraft, U.S....

  14. 33 CFR 334.490 - Atlantic Ocean off Georgia Coast; air-to-air and air-to-water gunnery and bombing ranges for...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., U.S. Air Force. (a) The danger zones—(1) For fighter aircraft. An area approximately 30 miles... Officer, 2d Bombardment Wing, Hunter Air Force Base, Savannah, Georgia, and such agencies as he may...; air-to-air and air-to-water gunnery and bombing ranges for fighter and bombardment aircraft, U.S....

  15. 33 CFR 334.490 - Atlantic Ocean off Georgia Coast; air-to-air and air-to-water gunnery and bombing ranges for...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., U.S. Air Force. (a) The danger zones—(1) For fighter aircraft. An area approximately 30 miles... Officer, 2d Bombardment Wing, Hunter Air Force Base, Savannah, Georgia, and such agencies as he may...; air-to-air and air-to-water gunnery and bombing ranges for fighter and bombardment aircraft, U.S....

  16. Silicon device performance measurements to support temperature range enhancement

    NASA Technical Reports Server (NTRS)

    Bromstead, James; Weir, Bennett; Nelms, R. Mark; Johnson, R. Wayne; Askew, Ray

    1994-01-01

    Silicon based power devices can be used at 200 C. The device measurements made during this program show a predictable shift in device parameters with increasing temperature. No catastrophic or abrupt changes occurred in the parameters over the temperature range. As expected, the most dramatic change was the increase in leakage currents with increasing temperature. At 200 C the leakage current was in the milliAmp range but was still several orders of magnitude lower than the on-state current capabilities of the devices under test. This increase must be considered in the design of circuits using power transistors at elevated temperature. Three circuit topologies have been prototyped using MOSFET's and IGBT's. The circuits were designed using zero current or zero voltage switching techniques to eliminate or minimize hard switching of the power transistors. These circuits have functioned properly over the temperature range. One thousand hour life data have been collected for two power supplies with no failures and no significant change in operating efficiency. While additional reliability testing should be conducted, the feasibility of designing soft switched circuits for operation at 200 C has been successfully demonstrated.

  17. Pd-modified Reactive Air Braze for Increased Melting Temperature

    SciTech Connect

    Hardy, John S.; Weil, K. Scott; Kim, Jin Yong Y.; Darsell, Jens T.

    2005-03-01

    Complex high temperature devices such as planar solid oxide fuel cell (pSOFC) stacks often require a two-step sealing process. For example, in pSOFC stacks the oxide ceramic fuel cell plates might be sealed into metallic support frames in one step. Then the frames with the fuel plates sealed to them would be joined together in a separate sealing step to form the fuel cell stack. In this case, the initial seal should have a sufficiently high solidus temperature that it will not begin to remelt at the sealing temperature of the material used for the subsequent sealing step. Previous experience has indicated that, when heated at a rate of 10°C/min, Ag-CuO reactive air braze (RAB) compositions have solidus and liquidus temperatures in the approximate range of 925 to 955°C. Therefore, compositionally modifying the original Ag-CuO braze with Pd-additions such that the solidus temperature of the new braze is between 1025 and 1050°C would provide two RAB compositions with a difference in melting points large enough to allow reactive air brazing of both sets of seals in the fuel cell stack. This study determines the appropriate ratio of Pd to Ag in RAB required to achieve a solidus in the desired range and discusses the wettability of the resulting Pd-Ag-CuO brazes on YSZ substrates. The interfacial microstructures and flexural strengths of Pd-Ag-CuO joints in YSZ will also be presented.

  18. Amplifier circuit operable over a wide temperature range

    DOEpatents

    Kelly, Ronald D.; Cannon, William L.

    1979-01-01

    An amplifier circuit having stable performance characteristics over a wide temperature range from approximately 0.degree. C up to as high as approximately 500.degree. C, such as might be encountered in a geothermal borehole. The amplifier utilizes ceramic vacuum tubes connected in directly coupled differential amplifier pairs having a common power supply and a cathode follower output stage. In an alternate embodiment, for operation up to 500.degree. C, positive and negative power supplies are utilized to provide improved gain characteristics, and all electrical connections are made by welding. Resistor elements in this version of the invention are specially heat treated to improve their stability with temperature.

  19. High accuracy magnetic field sensors with wide operation temperature range

    NASA Astrophysics Data System (ADS)

    Vasil'evskii, I. S.; Vinichenko, A. N.; Rubakin, D. I.; Bolshakova, I. A.; Kargin, N. I.

    2016-10-01

    n+InAs(Si) epitaxial thin films heavily doped by silicon and Hall effect magnetic field sensors based on this structures have been fabricated and studied. We have demonstrated the successful formation of highly doped InAs thin films (∼100 nm) with the different intermediate layer arrangement and appropriate electron mobility values. Hall sensors performance parameters have been measured in wide temperature range. Obtained sensitivity varied from 1 to 40 Ω/T, while the best linearity and lower temperature coefficient have been found in the higher doped samples with lower electron mobility. We attribute this to the electron system degeneracy and decreased phonon contribution to electron mobility and resistance.

  20. Increased risk of muscle tears below physiological temperature ranges

    PubMed Central

    Scott, E. E. F.; Hamilton, D. F.; Wallace, R. J.; Muir, A. Y.

    2016-01-01

    Objectives Temperature is known to influence muscle physiology, with the velocity of shortening, relaxation and propagation all increasing with temperature. Scant data are available, however, regarding thermal influences on energy required to induce muscle damage. Methods Gastrocnemius and soleus muscles were harvested from 36 male rat limbs and exposed to increasing impact energy in a mechanical test rig. Muscle temperature was varied in 5°C increments, from 17°C to 42°C (to encompass the in vivo range). The energy causing non-recoverable deformation was recorded for each temperature. A measure of tissue elasticity was determined via accelerometer data, smoothed by low-pass fifth order Butterworth filter (10 kHz). Data were analysed using one-way analysis of variance (ANOVA) and significance was accepted at p = 0.05. Results The energy required to induce muscle failure was significantly lower at muscle temperatures of 17°C to 32°C compared with muscle at core temperature, i.e., 37°C (p < 0.01). During low-energy impacts there were no differences in muscle elasticity between cold and warm muscles (p = 0.18). Differences in elasticity were, however, seen at higher impact energies (p < 0.02). Conclusion Our findings are of particular clinical relevance, as when muscle temperature drops below 32°C, less energy is required to cause muscle tears. Muscle temperatures of 32°C are reported in ambient conditions, suggesting that it would be beneficial, particularly in colder environments, to ensure that peripheral muscle temperature is raised close to core levels prior to high-velocity exercise. Thus, this work stresses the importance of not only ensuring that the muscle groups are well stretched, but also that all muscle groups are warmed to core temperature in pre-exercise routines. Cite this article: Professor A. H. R. W. Simpson. Increased risk of muscle tears below physiological temperature ranges. Bone Joint Res 2016;5:61–65. DOI: 10

  1. Correction of Temperatures of Air-Cooled Engine Cylinders for Variation in Engine and Cooling Conditions

    NASA Technical Reports Server (NTRS)

    Schey, Oscar W; Pinkel, Benjamin; Ellerbrock, Herman H , Jr

    1939-01-01

    Factors are obtained from semiempirical equations for correcting engine-cylinder temperatures for variation in important engine and cooling conditions. The variation of engine temperatures with atmospheric temperature is treated in detail, and correction factors are obtained for various flight and test conditions, such as climb at constant indicated air speed, level flight, ground running, take-off, constant speed of cooling air, and constant mass flow of cooling air. Seven conventional air-cooled engine cylinders enclosed in jackets and cooled by a blower were tested to determine the effect of cooling-air temperature and carburetor-air temperature on cylinder temperatures. The cooling air temperature was varied from approximately 80 degrees F. to 230 degrees F. and the carburetor-air temperature from approximately 40 degrees F. to 160 degrees F. Tests were made over a large range of engine speeds, brake mean effective pressures, and pressure drops across the cylinder. The correction factors obtained experimentally are compared with those obtained from the semiempirical equations and a fair agreement is noted.

  2. Wide temperature range electronic device with lead attachment

    NASA Technical Reports Server (NTRS)

    Farrell, R. (Inventor)

    1973-01-01

    A electronic device including lead attachment structure which permits operation of the devices over a wide temperature range is reported. The device comprises a core conductor having a thin coating of metal thereon whereby only a limited amount of coating material is available to form an alloy which bonds the core conductor to the device electrode, the electrode composition thus being affected only in the region adjacent to the lead.

  3. Estimation of Surface Air Temperature from MODIS 1km Resolution Land Surface Temperature Over Northern China

    NASA Technical Reports Server (NTRS)

    Shen, Suhung; Leptoukh, Gregory G.; Gerasimov, Irina

    2010-01-01

    Surface air temperature is a critical variable to describe the energy and water cycle of the Earth-atmosphere system and is a key input element for hydrology and land surface models. It is a very important variable in agricultural applications and climate change studies. This is a preliminary study to examine statistical relationships between ground meteorological station measured surface daily maximum/minimum air temperature and satellite remotely sensed land surface temperature from MODIS over the dry and semiarid regions of northern China. Studies were conducted for both MODIS-Terra and MODIS-Aqua by using year 2009 data. Results indicate that the relationships between surface air temperature and remotely sensed land surface temperature are statistically significant. The relationships between the maximum air temperature and daytime land surface temperature depends significantly on land surface types and vegetation index, but the minimum air temperature and nighttime land surface temperature has little dependence on the surface conditions. Based on linear regression relationship between surface air temperature and MODIS land surface temperature, surface maximum and minimum air temperatures are estimated from 1km MODIS land surface temperature under clear sky conditions. The statistical errors (sigma) of the estimated daily maximum (minimum) air temperature is about 3.8 C(3.7 C).

  4. Temperature range of the liquid-glass transition

    NASA Astrophysics Data System (ADS)

    Sanditov, D. S.; Darmaev, M. V.; Sanditov, B. D.

    2016-02-01

    It has been shown that the currently used method for calculating the temperature range of δ T g in the glass transition equation qτ g = δ T g as the difference δ T g = ( T 12- T 13) results in overestimated values, which is explained by the assumption of a constant activation energy of glass transition in deriving the calculation equation ( T 12 and T 13 are the temperatures corresponding to the logarithmic viscosity values of logη = 12 and logη = 13). The methods for the evaluation of δ T g using the Williams-Landel-Ferry equation and the model of delocalized atoms are considered, the results of which are in satisfactory agreement with the product qτ g ( q is the cooling rate of the melt and τ g is the structural relaxation time at the glass transition temperature). The calculation of τ g for inorganic glasses and amorphous organic polymers is proposed.

  5. On extreme rainfall intensity increases with air temperature

    NASA Astrophysics Data System (ADS)

    Molnar, Peter; Fatichi, Simone; Paschalis, Athanasios; Gaal, Ladislav; Szolgay, Jan; Burlando, Paolo

    2016-04-01

    The water vapour holding capacity of air increases at about 7% per degree C according to the Clausius-Clapeyron (CC) relation. This is one of the arguments why a warmer future atmosphere, being able to hold more moisture, will generate higher extreme precipitation intensities. However, several empirical studies have recently demonstrated an increase in extreme rain intensities with air temperature above CC rates, in the range 7-14% per degree C worldwide (called super-CC rates). This was observed especially for shorter duration rainfall, i.e. in hourly and finer resolution data (e.g. review in Westra et al., 2014). The super-CC rate was attributed to positive feedbacks between water vapour and the updraft dynamics in convective clouds and lateral supply (convergence) of moisture. In addition, mixing of storm types was shown to be potentially responsible for super-CC rates in empirical studies. Assuming that convective events are accompanied by lightning, we will show on a large rainfall dataset in Switzerland (30 year records of 10-min and 1-hr data from 59 stations) that while the average rate of increase in extreme rainfall intensity (95th percentile) is 6-7% in no-lightning events and 8-9% in lightning events, it is 11-13% per degree C when all events are combined (Molnar et al., 2015). These results are relevant for climate change studies which predict shifts in storm types in a warmer climate in some parts of the world. The observation that extreme rain intensity and air temperature are positively correlated has consequences for the stochastic modelling of rainfall. Most current stochastic models do not explicitly include a direct rain intensity-air temperature dependency beyond applying factors of change predicted by climate models to basic statistics of precipitation. Including this dependency explicitly in stochastic models will allow, for example in the nested modelling approach of Paschalis et al. (2014), the random cascade disaggregation routine to be

  6. Air Surface Temperature Correlation with Greenhouse Gases by Using Airs Data Over Peninsular Malaysia

    NASA Astrophysics Data System (ADS)

    Rajab, Jasim Mohammed; MatJafri, M. Z.; Lim, H. S.

    2014-08-01

    The main objective of this study is to develop algorithms for calculating the air surface temperature (AST). This study also aims to analyze and investigate the effects of greenhouse gases (GHGs) on the AST value in Peninsular Malaysia. Multiple linear regression is used to achieve the objectives of the study. Peninsular Malaysia has been selected as the research area because it is among the regions of tropical Southeast Asia with the greatest humidity, pockets of heavy pollution, rapid economic growth, and industrialization. The predicted AST was highly correlated ( R = 0.783) with GHGs for the 6-year data (2003-2008). Comparisons of five stations in 2009 showed close agreement between the predicted AST and the observed AST from AIRS, especially in the wet season (within 1.3 K). The in situ data ranged from 1 to 2 K. Validation results showed that AST ( R = 0.776-0.878) has values nearly the same as the observed AST from AIRS. We found that O3 during the wet season was indicated by a strongly positive beta coefficient (0.264-0.992) with AST. The CO2 yields a reasonable relationship with temperature with low to moderate beta coefficient (-0.065 to 0.238). The O3, CO2, and environmental variables experienced different seasonal fluctuations that depend on weather conditions and topography. The concentration of gases and pollution were the highest over industrial zones and overcrowded cities, and the dry season was more polluted compared with the wet season. These results indicate the advantage of using the satellite AIRS data and a correlation analysis to investigate the effect of atmospheric GHGs on AST over Peninsular Malaysia. An algorithm that is capable of retrieving Peninsular Malaysian AST in all weather conditions with total uncertainties ranging from 1 to 2 K was developed.

  7. Large diurnal temperature range increases bird sensitivity to climate change.

    PubMed

    Briga, Michael; Verhulst, Simon

    2015-11-13

    Climate variability is changing on multiple temporal scales, and little is known of the consequences of increases in short-term variability, particularly in endotherms. Using mortality data with high temporal resolution of zebra finches living in large outdoor aviaries (5 years, 359.220 bird-days), we show that mortality rate increases almost two-fold per 1°C increase in diurnal temperature range (DTR). Interestingly, the DTR effect differed between two groups with low versus high experimentally manipulated foraging costs, reflecting a typical laboratory 'easy' foraging environment and a 'hard' semi-natural environment respectively. DTR increased mortality on days with low minimum temperature in the easy foraging environment, but on days with high minimum temperature in the semi-natural environment. Thus, in a natural environment DTR effects will become increasingly important in a warming world, something not detectable in an 'easy' laboratory environment. These effects were particularly apparent at young ages. Critical time window analyses showed that the effect of DTR on mortality is delayed up to three months, while effects of minimum temperature occurred within a week. These results show that daily temperature variability can substantially impact the population viability of endothermic species.

  8. Short-range optical air data measurements for aircraft control using rotational Raman backscatter.

    PubMed

    Fraczek, Michael; Behrendt, Andreas; Schmitt, Nikolaus

    2013-07-15

    A first laboratory prototype of a novel concept for a short-range optical air data system for aircraft control and safety was built. The measurement methodology was introduced in [Appl. Opt. 51, 148 (2012)] and is based on techniques known from lidar detecting elastic and Raman backscatter from air. A wide range of flight-critical parameters, such as air temperature, molecular number density and pressure can be measured as well as data on atmospheric particles and humidity can be collected. In this paper, the experimental measurement performance achieved with the first laboratory prototype using 532 nm laser radiation of a pulse energy of 118 mJ is presented. Systematic measurement errors and statistical measurement uncertainties are quantified separately. The typical systematic temperature, density and pressure measurement errors obtained from the mean of 1000 averaged signal pulses are small amounting to < 0.22 K, < 0.36% and < 0.31%, respectively, for measurements at air pressures varying from 200 hPa to 950 hPa but constant air temperature of 298.95 K. The systematic measurement errors at air temperatures varying from 238 K to 308 K but constant air pressure of 946 hPa are even smaller and < 0.05 K, < 0.07% and < 0.06%, respectively. A focus is put on the system performance at different virtual flight altitudes as a function of the laser pulse energy. The virtual flight altitudes are precisely generated with a custom-made atmospheric simulation chamber system. In this context, minimum laser pulse energies and pulse numbers are experimentally determined, which are required using the measurement system, in order to meet measurement error demands for temperature and pressure specified in aviation standards. The aviation error margins limit the allowable temperature errors to 1.5 K for all measurement altitudes and the pressure errors to 0.1% for 0 m and 0.5% for 13000 m. With regard to 100-pulse-averaged temperature measurements, the pulse energy using 532 nm

  9. Effectiveness of an air-cooled vest using selected air temperature and humidity combinations.

    PubMed

    Pimental, N A; Cosimini, H M; Sawka, M N; Wenger, C B

    1987-02-01

    We evaluated the effectiveness of an air-cooled vest in reducing thermal strain of subjects exercising in the heat (49 degrees C dry bulb (db), 20 degrees C dew point (dp] in chemical protective clothing. Four male subjects attempted 300-min heat exposures at two metabolic rates (175 and 315 W) with six cooling combinations--control (no vest) and five different db and dp combinations. Air supplied to the vest at 15 scfm ranged from 20-27 degrees C db, 7-18 degrees C dp; theoretical cooling capacities were 498-687 W. Without the vest, endurance times were 118 min (175 W) and 73 min (315 W). Endurance times with the vest were 300 min (175 W) and 242-300 min (315 W). The five cooling combinations were similarly effective in reducing thermal strain and extending endurance time, although there was a trend for the vest to be more effective when supplied with air at the lower dry bulb temperature. At 175 W, subjects maintained a constant body temperature; at 315 W, the vest's ability to extend endurance is limited to about 5 hours.

  10. A wide-frequency-range air-jet shaker

    NASA Technical Reports Server (NTRS)

    Herr, Robert W

    1957-01-01

    This paper presents a description of a simple air-jet shaker. Its force can be calibrated statically and appears to be constant with frequency. It is relatively easy to use, and it has essentially massless characteristics. This shaker is applied to define the unstable branch of a frequency-response curve obtained for a nonlinear spring with a single degree of freedom.

  11. Assessing surface air temperature variability using quantile regression

    NASA Astrophysics Data System (ADS)

    Timofeev, A. A.; Sterin, A. M.

    2014-12-01

    Many researches in climate change currently involve linear trends, based on measured variables. And many of them only consider trends in mean values, whereas it is clear, that not only means, but also whole shape of distribution changes over time and requires careful assessment. For example extreme values including outliers may get bigger, while median has zero slope.Quantile regression provides a convenient tool, that enables detailed analysis of changes in full range of distribution by producing a vector of quantile trends for any given set of quantiles.We have applied quantile regression to surface air temperature observations made at over 600 weather stations across Russian Federation during last four decades. The results demonstrate well pronounced regions with similar values of significant trends in different parts of temperature value distribution (left tail, middle part, right tail). The uncertainties of quantile trend estimations for several spatial patterns of trends over Russia are estimated and analyzed for each of four seasons.For temperature trend estimation over vast territories, quantile regression is an effort consuming approach, but is more informative than traditional instrument, to assess decadal evolution of temperature values, including evolution of extremes.Partial support of ERA NET RUS ACPCA joint project between EU and RBRF 12-05-91656-ЭРА-А is highly appreciated.

  12. Short-Range Correlations in Magnetite above the Verwey Temperature

    NASA Astrophysics Data System (ADS)

    Bosak, Alexey; Chernyshov, Dmitry; Hoesch, Moritz; Piekarz, Przemysław; Le Tacon, Mathieu; Krisch, Michael; Kozłowski, Andrzej; Oleś, Andrzej M.; Parlinski, Krzysztof

    2014-01-01

    Magnetite, Fe3O4, is the first magnetic material discovered and utilized by mankind in Ancient Greece, yet it still attracts attention due to its puzzling properties. This is largely due to the quest for a full and coherent understanding of the Verwey transition that occurs at TV=124 K and is associated with a drop of electric conductivity and a complex structural phase transition. A recent detailed analysis of the structure, based on single crystal diffraction, suggests that the electron localization pattern contains linear three-Fe-site units, the so-called trimerons. Here, we show that whatever the electron localization pattern is, it partially survives up to room temperature as short-range correlations in the high-temperature cubic phase, easily discernible by diffuse scattering. Additionally, ab initio electronic structure calculations reveal that characteristic features in these diffuse scattering patterns can be correlated with the Fermi surface topology.

  13. Comparison of MODIS Land Surface Temperature and Air Temperature over the Continental USA Meteorological Stations

    NASA Technical Reports Server (NTRS)

    Zhang, Ping; Bounoua, Lahouari; Imhoff, Marc L.; Wolfe, Robert E.; Thome, Kurtis

    2014-01-01

    The National Land Cover Database (NLCD) Impervious Surface Area (ISA) and MODIS Land Surface Temperature (LST) are used in a spatial analysis to assess the surface-temperature-based urban heat island's (UHIS) signature on LST amplitude over the continental USA and to make comparisons to local air temperatures. Air-temperature-based UHIs (UHIA), calculated using the Global Historical Climatology Network (GHCN) daily air temperatures, are compared with UHIS for urban areas in different biomes during different seasons. NLCD ISA is used to define urban and rural temperatures and to stratify the sampling for LST and air temperatures. We find that the MODIS LST agrees well with observed air temperature during the nighttime, but tends to overestimate it during the daytime, especially during summer and in nonforested areas. The minimum air temperature analyses show that UHIs in forests have an average UHIA of 1 C during the summer. The UHIS, calculated from nighttime LST, has similar magnitude of 1-2 C. By contrast, the LSTs show a midday summer UHIS of 3-4 C for cities in forests, whereas the average summer UHIA calculated from maximum air temperature is close to 0 C. In addition, the LSTs and air temperatures difference between 2006 and 2011 are in agreement, albeit with different magnitude.

  14. Retrieval of air temperatures from crowd-sourced battery temperatures of cell phones

    NASA Astrophysics Data System (ADS)

    Overeem, Aart; Robinson, James; Leijnse, Hidde; Uijlenhoet, Remko; Steeneveld, Gert-Jan; Horn, Berthold K. P.

    2013-04-01

    Accurate air temperature observations are important for urban meteorology, for example to study the urban heat island and adverse effects of high temperatures on human health. The number of available temperature observations is often relatively limited. A new development is presented to derive temperature information for the urban canopy from an alternative source: cell phones. Battery temperature data were collected by users of an Android application for cell phones (opensignal.com). The application automatically sends battery temperature data to a server for storage. In this study, battery temperatures are averaged in space and time to obtain daily averaged battery temperatures for each city separately. A regression model, which can be related to a physical model, is employed to retrieve daily air temperatures from battery temperatures. The model is calibrated with observed air temperatures from a meteorological station of an airport located in or near the city. Time series of air temperatures are obtained for each city for a period of several months, where 50% of the data is for independent verification. Results are presented for Buenos Aires, London, Los Angeles, Paris, Mexico City, Moscow, Rome, and Sao Paulo. The evolution of the retrieved air temperatures often correspond well with the observed ones. The mean absolute error of daily air temperatures is less than 2 degrees Celsius, and the bias is within 1 degree Celsius. This shows that monitoring air temperatures employing an Android application holds great promise. Since 75% of the world's population has a cell phone, 20% of the land surface of the earth has cellular telephone coverage, and 500 million devices use the Android operating system, there is a huge potential for measuring air temperatures employing cell phones. This could eventually lead to real-time world-wide temperature maps.

  15. The association between diurnal temperature range and childhood bacillary dysentery

    NASA Astrophysics Data System (ADS)

    Wen, Li-ying; Zhao, Ke-fu; Cheng, Jian; Wang, Xu; Yang, Hui-hui; Li, Ke-sheng; Xu, Zhi-wei; Su, Hong

    2016-02-01

    Previous studies have found that mean, maximum, and minimum temperatures were associated with bacillary dysentery (BD). However, little is known about whether the within-day variation of temperature has any impact on bacillary dysentery. The current study aimed to identify the relationship between diurnal temperature range (DTR) and BD in Hefei, China. Daily data on BD counts among children aged 0-14 years from 1 January 2006 to 31 December 2012 were retrieved from Hefei Center for Disease Control and Prevention. Daily data on ambient temperature and relative humidity covering the same period were collected from the Hefei Bureau of Meteorology. A Poisson generalized linear regression model combined with a distributed lag non-linear model (DLNM) was used in the analysis after controlling the effects of season, long-term trends, mean temperature, and relative humidity. The results showed that there existed a statistically significant relationship between DTR and childhood BD. The DTR effect on childhood bacillary dysentery increased when DTR was over 8 °C. And it was greatest at 1-day lag, with an 8 % (95 % CI = 2.9-13.4 %) increase of BD cases per 5 °C increment of DTR. Male children and children aged 0-5 years appeared to be more vulnerable to the DTR effect. The data indicate that large DTR may increase the incidence of childhood BD. Caregivers and health practitioners should be made aware of the potential threat posed by large DTR. Therefore, DTR should be taken into consideration when making targeted health policies and programs to protect children from being harmed by climate impacts.

  16. The association between diurnal temperature range and childhood bacillary dysentery.

    PubMed

    Wen, Li-ying; Zhao, Ke-fu; Cheng, Jian; Wang, Xu; Yang, Hui-hui; Li, Ke-sheng; Xu, Zhi-wei; Su, Hong

    2016-02-01

    Previous studies have found that mean, maximum, and minimum temperatures were associated with bacillary dysentery (BD). However, little is known about whether the within-day variation of temperature has any impact on bacillary dysentery. The current study aimed to identify the relationship between diurnal temperature range (DTR) and BD in Hefei, China. Daily data on BD counts among children aged 0-14 years from 1 January 2006 to 31 December 2012 were retrieved from Hefei Center for Disease Control and Prevention. Daily data on ambient temperature and relative humidity covering the same period were collected from the Hefei Bureau of Meteorology. A Poisson generalized linear regression model combined with a distributed lag non-linear model (DLNM) was used in the analysis after controlling the effects of season, long-term trends, mean temperature, and relative humidity. The results showed that there existed a statistically significant relationship between DTR and childhood BD. The DTR effect on childhood bacillary dysentery increased when DTR was over 8 °C. And it was greatest at 1-day lag, with an 8% (95% CI = 2.9-13.4%) increase of BD cases per 5 °C increment of DTR. Male children and children aged 0-5 years appeared to be more vulnerable to the DTR effect. The data indicate that large DTR may increase the incidence of childhood BD. Caregivers and health practitioners should be made aware of the potential threat posed by large DTR. Therefore, DTR should be taken into consideration when making targeted health policies and programs to protect children from being harmed by climate impacts.

  17. Solar Eclipse Effect on Shelter Air Temperature

    NASA Technical Reports Server (NTRS)

    Segal, M.; Turner, R. W.; Prusa, J.; Bitzer, R. J.; Finley, S. V.

    1996-01-01

    Decreases in shelter temperature during eclipse events were quantified on the basis of observations, numerical model simulations, and complementary conceptual evaluations. Observations for the annular eclipse on 10 May 1994 over the United States are presented, and these provide insights into the temporal and spatial changes in the shelter temperature. The observations indicated near-surface temperature drops of as much as 6 C. Numerical model simulations for this eclipse event, which provide a complementary evaluation of the spatial and temporal patterns of the temperature drops, predict similar decreases. Interrelationships between the temperature drop, degree of solar irradiance reduction, and timing of the peak eclipse are also evaluated for late spring, summer, and winter sun conditions. These simulations suggest that for total eclipses the drops in shelter temperature in midlatitudes can be as high as 7 C for a spring morning eclipse.

  18. Monitored summer peak attic air temperatures in Florida residences

    SciTech Connect

    Parker, D.S.; Sherwin, J.R.

    1998-12-31

    The Florida Solar Energy Center (FSEC) has analyzed measured summer attic air temperature data taken for some 21 houses (three with two different roof configurations) over the last several years. The analysis is in support of the calculation within ASHRAE Special Project 152P, which will be used to estimate duct system conductance gains that are exposed to the attic space. Knowledge of prevailing attic thermal conditions are critical to the duct heat transfer calculations for estimation of impacts on residential cooling system sizing. The field data were from a variety of residential monitoring projects that were classified according to intrinsic differences in roofing configurations and characteristics. The sites were occupied homes spread around the state of Florida. There were a variety of different roofing construction types, roof colors, and ventilation configurations. Data at each site were obtained from June 1 to September 30 according to the ASHRAE definition of summer. The attic air temperature and ambient air temperature were used for the data analysis. The attic air temperature was measured with a shielded type-T thermocouple at mid-attic height, halfway between the decking and insulation surface. The ambient air temperature was obtained at each site by thermocouples located inside a shielded exterior enclosure at a 3 to 4 m (10--12 ft) height. The summer 15-minute data from each site were sorted by the average ambient air temperature into the top 2.5% of the observations of the highest temperature. Within this limited group of observations, the average outside air temperature, attic air temperature, and coincident difference were reported.

  19. Solar activity influence on air temperature regimes in caves

    NASA Astrophysics Data System (ADS)

    Stoeva, Penka; Mikhalev, Alexander; Stoev, Alexey

    Cave atmospheres are generally included in the processes that happen in the external atmosphere as circulation of the cave air is connected with the most general circulation of the air in the earth’s atmosphere. Such isolated volumes as the air of caves are also influenced by the variations of solar activity. We discuss cave air temperature response to climate and solar and geomagnetic activity for four show caves in Bulgaria studied for a period of 46 years (1968 - 2013). Everyday noon measurements in Ledenika, Saeva dupka, Snezhanka and Uhlovitsa cave have been used. Temperatures of the air in the zone of constant temperatures (ZCT) are compared with surface temperatures recorded at meteorological stations situated near about the caves - in the towns of Vratsa, Lovech, Peshtera and Smolyan, respectively. For comparison, The Hansen cave, Middle cave and Timpanogos cave from the Timpanogos Cave National Monument, Utah, USA situated nearly at the same latitude have also been examined. Our study shows that the correlation between cave air temperature time series and sunspot number is better than that between the cave air temperature and Apmax indices; that t°ZCT is rather connected with the first peak in geomagnetic activity, which is associated with transient solar activity (CMEs) than with the second one, which is higher and connected with the recurrent high speed streams from coronal holes. Air temperatures of all examined show caves, except the Ledenika cave, which is ice cave show decreasing trends. On the contrary, measurements at the meteorological stations show increasing trends in the surface air temperatures. The trend is decreasing for the Timpanogos cave system, USA. The conclusion is that surface temperature trends depend on the climatic zone, in which the cave is situated, and there is no apparent relation between temperatures inside and outside the caves. We consider possible mechanism of solar cosmic rays influence on the air temperatures in caves

  20. Changes in diurnal temperature range and national cereal yields

    SciTech Connect

    Lobell, D

    2007-04-26

    Models of yield responses to temperature change have often considered only changes in average temperature (Tavg), with the implicit assumption that changes in the diurnal temperature range (DTR) can safely be ignored. The goal of this study was to evaluate this assumption using a combination of historical datasets and climate model projections. Data on national crop yields for 1961-2002 in the 10 leading producers of wheat, rice, and maize were combined with datasets on climate and crop locations to evaluate the empirical relationships between Tavg, DTR, and crop yields. In several rice and maize growing regions, including the two major nations for each crop, there was a clear negative response of yields to increased DTR. This finding reflects a nonlinear response of yields to temperature, which likely results from greater water and heat stress during hot days. In many other cases, the effects of DTR were not statistically significant, in part because correlations of DTR with other climate variables and the relatively short length of the time series resulted in wide confidence intervals for the estimates. To evaluate whether future changes in DTR are relevant to crop impact assessments, yield responses to projected changes in Tavg and DTR by 2046-2065 from 11 climate models were estimated. The mean climate model projections indicated an increase in DTR in most seasons and locations where wheat is grown, mixed projections for maize, and a general decrease in DTR for rice. These mean projections were associated with wide ranges that included zero in nearly all cases. The estimated impacts of DTR changes on yields were generally small (<5% change in yields) relative to the consistently negative impact of projected warming of Tavg. However, DTR changes did significantly affect yield responses in several cases, such as in reducing US maize yields and increasing India rice yields. Because DTR projections tend to be positively correlated with Tavg, estimates of yields

  1. Associations of endothelial function and air temperature in diabetic subjects

    EPA Science Inventory

    Background and Objective: Epidemiological studies consistently show that air temperature is associated with changes in cardiovascular morbidity and mortality. However, the biological mechanisms underlying the association remain largely unknown. As one index of endothelial functio...

  2. 40 CFR 91.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... must be made within 100 cm of the air-intake of the engine. The measurement location must be either in... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air temperature... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test...

  3. 40 CFR 91.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... must be made within 100 cm of the air-intake of the engine. The measurement location must be either in... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test...

  4. 40 CFR 90.309 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... location must be within 10 cm of the engine intake system (i.e., the air cleaner, for most engines.) (b... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19...

  5. High Lapse Rates in AIRS Retrieved Temperatures in Cold Air Outbreaks

    NASA Technical Reports Server (NTRS)

    Fetzer, Eric J.; Kahn, Brian; Olsen, Edward T.; Fishbein, Evan

    2004-01-01

    The Atmospheric Infrared Sounder (AIRS) experiment, on NASA's Aqua spacecraft, uses a combination of infrared and microwave observations to retrieve cloud and surface properties, plus temperature and water vapor profiles comparable to radiosondes throughout the troposphere, for cloud cover up to 70%. The high spectral resolution of AIRS provides sensitivity to important information about the near-surface atmosphere and underlying surface. A preliminary analysis of AIRS temperature retrievals taken during January 2003 reveals extensive areas of superadiabatic lapse rates in the lowest kilometer of the atmosphere. These areas are found predominantly east of North America over the Gulf Stream, and, off East Asia over the Kuroshio Current. Accompanying the high lapse rates are low air temperatures, large sea-air temperature differences, and low relative humidities. Imagery from a Visible / Near Infrared instrument on the AIRS experiment shows accompanying clouds. These lines of evidence all point to shallow convection in the bottom layer of a cold air mass overlying warm water, with overturning driven by heat flow from ocean to atmosphere. An examination of operational radiosondes at six coastal stations in Japan shows AIRS to be oversensitive to lower tropospheric lapse rates due to systematically warm near-surface air temperatures. The bias in near-surface air temperature is seen to be independent of sea surface temperature, however. AIRS is therefore sensitive to air-sea temperature difference, but with a warm atmospheric bias. A regression fit to radiosondes is used to correct AIRS near-surface retrieved temperatures, and thereby obtain an estimate of the true atmosphere-ocean thermal contrast in five subtropical regions across the north Pacific. Moving eastward, we show a systematic shift in this air-sea temperature differences toward more isothermal conditions. These results, while preliminary, have implications for our understanding of heat flow from ocean to

  6. Environmental Assessment: Black-Tailed Prairie Dog Management Cannon Air Force Base and Melrose Air Force Range, New Mexico

    DTIC Science & Technology

    2005-12-01

    1997). Domestic dogs and cats passing through prairie dog towns are susceptible to infection and may carry fleas to residential areas where humans...the Proposed Action is to manage the prairie dog population to ensure ecosystem stability, population control, genetic diversity, and successful...Environmental Assessment for Black-Tailed Prairie Dog Management for Cannon Air Force Base and Melrose Air Force Range, New Mexico United States Air

  7. A methodology for long-range prediction of air transportation

    NASA Technical Reports Server (NTRS)

    Ayati, M. B.; English, J. M.

    1980-01-01

    A framework and methodology for long term projection of demand for aviation fuels is presented. The approach taken includes two basic components. The first was a new technique for establishing the socio-economic environment within which the future aviation industry is embedded. The concept utilized was a definition of an overall societal objective for the very long run future. Within a framework so defined, a set of scenarios by which the future will unfold are then written. These scenarios provide the determinants of the air transport industry operations and accordingly provide an assessment of future fuel requirements. The second part was the modeling of the industry in terms of an abstracted set of variables to represent the overall industry performance on a macro scale. The model was validated by testing the desired output variables from the model with historical data over the past decades.

  8. Microcalorimetry: Wide Temperature Range, High Field, Small Sample Measurements

    NASA Astrophysics Data System (ADS)

    Hellman, Frances

    2000-03-01

    We have used Si micromachining techniques to fabricate devices for measuring specific heat or other calorimetric signals from microgram-quantity samples over a temperature range from 1 to 900K in magnetic fields to date up to 8T. The devices are based on a relatively robust silicon nitride membrane with thin film heaters and thermometers. Different types of thermometers are used for different purposes and in different temperature ranges. These devices are particularly useful for thin film samples (typically 200-400 nm thick at present) deposited directly onto the membrane through a Si micromachined evaporation mask. They have also been used for small single crystal samples attached by conducting grease or solder, and for powder samples dissolved in a solvent and dropped onto devices. The measurement technique used (relaxation method) is particularly suited to high field measurements because the thermal conductance can be measured once in zero field and is field independent, while the time constant of the relaxation does not depend on thermometer calibration. Present development efforts include designs which show promise for time-resolved calorimetry measurements of biological samples in small amounts of water. Samples measured to date include amorphous magnetic thin films (a-TbFe2 and giant negative magnetoresistance a-Gd-Si alloys), empty and filled fullerenes (C_60, K_3C_60, C_82, La@C_82, C_84, and Sc_2@C_84), single crystal manganites (La_1-xSr_xMnO_3), antiferromagnetic multilayers (NiO/CoO, NiO/MgO, and CoO/MgO), and nanoparticle magnetic materials (CoO in a Ag matrix).

  9. Geographical and Geomorphological Effects on Air Temperatures in the Columbia Basin's Signature Vineyards

    NASA Astrophysics Data System (ADS)

    Olson, L.; Pogue, K. R.; Bader, N.

    2012-12-01

    controlled by elevation. In some AVAs, such as Walla Walla Valley and Red Mountain, average air temperatures increased with elevation because of the effect of cold air pooling on valley floors. In other AVAs, such as Horse Heaven Hills, Lake Chelan and Columbia Gorge, average temperatures decreased with elevation due to the moderating influences of the Columbia River and Lake Chelan. Other temperature statistics, including average diurnal range and maximum and minimum temperature, were influenced by relative topography, including local topography and slope. Vineyards with flat slopes that had low elevations relative to their surroundings had larger diurnal variations and lower maximum and minimum temperatures than vineyards with steeper slopes that were high relative to their surroundings.

  10. Observations of a "weekend effect" in diurnal temperature range.

    PubMed

    Forster, Piers M de F; Solomon, Susan

    2003-09-30

    Using surface measurements of maximum and minimum temperatures from the Global Daily Climatological Network data set, we find evidence of a weekly cycle in diurnal temperature range (DTR) for many stations in the United States, Mexico, Japan, and China. The "weekend effect," which we define as the average DTR for Saturday through Monday minus the average DTR for Wednesday through Friday, can be as large as 0.5 K, similar to the magnitude of observed long-term trends in DTR. This weekend effect has a distinct large-scale pattern that has changed only slightly over time, but its sign is not the same in all locations. The station procedures and the statistical robustness of both the individual station data and the patterns of DTR differences are thoroughly examined. We conclude that the weekend effect is a real short time scale and large spatial scale geophysical phenomenon, which is necessarily human in origin. We thus provide strong evidence of an anthropogenic link to DTR, an important climate indicator. Several possible anthropogenic mechanisms are discussed; we speculate that aerosol-cloud interactions are the most likely cause of this weekend effect, but we do not rule out others.

  11. Strategic Long Range Planning for Universities. AIR Forum 1980 Paper.

    ERIC Educational Resources Information Center

    Baker, Michael E.

    The use of strategic long-range planning at Carnegie-Mellon University (CMU) is discussed. A structure for strategic planning analysis that integrates existing techniques is presented, and examples of planning activities at CMU are included. The key concept in strategic planning is competitive advantage: if a university has a competitive…

  12. Proposed Continental Operations Range. United States Air Force.

    DTIC Science & Technology

    1974-06-01

    See footnote. page 2-120) 2-122 I. NORTH RANGE 6, CALENTE figure 2.28. WotthsrU D)emert Shrub (See foottiote. Pago 2-120) 2-123 pine and Utah...specialist suggested any potential impact on ATC. He felt that ATC controller workload, and communications frequency con- gestion , would be increased

  13. Flow characteristics of an inclined air-curtain range hood in a draft

    PubMed Central

    CHEN, Jia-Kun

    2015-01-01

    The inclined air-curtain technology was applied to build an inclined air-curtain range hood. A draft generator was applied to affect the inclined air-curtain range hood in three directions: lateral (θ=0°), oblique (θ=45°), and front (θ=90°). The three suction flow rates provided by the inclined air-curtain range hood were 10.1, 10.9, and 12.6 m3/min. The laser-assisted flow visualization technique and the tracer-gas test method were used to investigate the performance of the range hood under the influence of a draft. The results show that the inclined air-curtain range hood has a strong ability to resist the negative effect of a front draft until the draft velocity is greater than 0.5 m/s. The oblique draft affected the containment ability of the inclined air-curtain range hood when the draft velocity was larger than 0.3 m/s. When the lateral draft effect was applied, the capture efficiency of the inclined air-curtain range hood decreased quickly in the draft velocity from 0.2 m/s to 0.3 m/s. However, the capture efficiencies of the inclined air-curtain range hood under the influence of the front draft were higher than those under the influence of the oblique draft from 0.3 m/s to 0.5 m/s. PMID:25810445

  14. 40 CFR 89.325 - Engine intake air temperature measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... temperature measurement must be made within 122 cm of the engine. The measurement location must be made either... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES...

  15. Temperature distribution of air source heat pump barn with different air flow

    NASA Astrophysics Data System (ADS)

    He, X.; Li, J. C.; Zhao, G. Q.

    2016-08-01

    There are two type of airflow form in tobacco barn, one is air rising, the other is air falling. They are different in the structure layout and working principle, which affect the tobacco barn in the distribution of temperature field and velocity distribution. In order to compare the temperature and air distribution of the two, thereby obtain a tobacco barn whose temperature field and velocity distribution are more uniform. Taking the air source heat pump tobacco barn as the investigated subject and establishing relevant mathematical model, the thermodynamics of the two type of curing barn was analysed and compared based on Fluent. Provide a reasonable evidence for chamber arrangement and selection of outlet for air source heat pump tobacco barn.

  16. Improving Forecast Skill by Assimilation of AIRS Temperature Soundings

    NASA Technical Reports Server (NTRS)

    Susskind, Joel; Reale, Oreste

    2010-01-01

    AIRS was launched on EOS Aqua on May 4, 2002, together with AMSU-A and HSB, to form a next generation polar orbiting infrared and microwave atmospheric sounding system. The primary products of AIRS/AMSU-A are twice daily global fields of atmospheric temperature-humidity profiles, ozone profiles, sea/land surface skin temperature, and cloud related parameters including OLR. The AIRS Version 5 retrieval algorithm, is now being used operationally at the Goddard DISC in the routine generation of geophysical parameters derived from AIRS/AMSU data. A major innovation in Version 5 is the ability to generate case-by-case level-by-level error estimates delta T(p) for retrieved quantities and the use of these error estimates for Quality Control. We conducted a number of data assimilation experiments using the NASA GEOS-5 Data Assimilation System as a step toward finding an optimum balance of spatial coverage and sounding accuracy with regard to improving forecast skill. The model was run at a horizontal resolution of 0.5 deg. latitude X 0.67 deg longitude with 72 vertical levels. These experiments were run during four different seasons, each using a different year. The AIRS temperature profiles were presented to the GEOS-5 analysis as rawinsonde profiles, and the profile error estimates delta (p) were used as the uncertainty for each measurement in the data assimilation process. We compared forecasts analyses generated from the analyses done by assimilation of AIRS temperature profiles with three different sets of thresholds; Standard, Medium, and Tight. Assimilation of Quality Controlled AIRS temperature profiles significantly improve 5-7 day forecast skill compared to that obtained without the benefit of AIRS data in all of the cases studied. In addition, assimilation of Quality Controlled AIRS temperature soundings performs better than assimilation of AIRS observed radiances. Based on the experiments shown, Tight Quality Control of AIRS temperature profile performs best

  17. Topographic and spatial impacts of temperature inversions on air quality using mobile air pollution surveys.

    PubMed

    Wallace, Julie; Corr, Denis; Kanaroglou, Pavlos

    2010-10-01

    We investigated the spatial and topographic effects of temperature inversions on air quality in the industrial city of Hamilton, located at the western tip of Lake Ontario, Canada. The city is divided by a 90-m high topographic scarp, the Niagara Escarpment, and dissected by valleys which open towards Lake Ontario. Temperature inversions occur frequently in the cooler seasons, exacerbating the impact of emissions from industry and traffic. This study used pollution data gathered from mobile monitoring surveys conducted over a 3-year period, to investigate whether the effects of the inversions varied across the city. Temperature inversions were identified with vertical temperature data from a meteorological tower located within the study area. We divided the study area into an upper and lower zone separated by the Escarpment and further into six zones, based on location with respect to the Escarpment and industrial and residential areas, to explore variations across the city. The results identified clear differences in the responses of nitrogen dioxide (NO(2)) and fine particulate matter (PM2.5) to temperature inversions, based on the topographic and spatial criteria. We found that pollution levels increased as the inversion strengthened, in the lower city. However, the results also suggested that temperature inversions identified in the lower city were not necessarily experienced in the upper city with the same intensity. Further, pollution levels in the upper city appeared to decrease as the inversion deepened in the lower city, probably because of an associated change in prevailing wind direction and lower wind speeds, leading to decreased long-range transport of pollutants.

  18. Equipment for Measuring Air Flow, Air Temperature, Relative Humidity, and Carbon Dioxide in Schools. Technical Bulletin.

    ERIC Educational Resources Information Center

    Jacobs, Bruce W.

    Information on equipment and techniques that school facility personnel may use to evaluate IAQ conditions are discussed. Focus is placed on the IAQ parameters of air flow, air temperature, relative humidity, as well as carbon dioxide and the equipment used to measure these factors. Reasons for measurement and for when the measurement of these…

  19. Temperature effect on titanium nitride nanometer thin film in air

    NASA Astrophysics Data System (ADS)

    Cen, Z. H.; Xu, B. X.; Hu, J. F.; Ji, R.; Toh, Y. T.; Ye, K. D.; Hu, Y. F.

    2017-02-01

    Titanium nitride (TiN) is a promising alternative plasmonic material to conventional novel metals. For practical plasmonic applications under the influence of air, the temperature-dependent optical properties of TiN thin films in air and its volume variation are essential. Ellipsometric characterizations on a TiN thin film at different increasing temperatures in ambient air were conducted, and optical constants along with film thickness were retrieved. Below 200 °C, the optical properties varied linearly with temperature, in good agreement with other temperature dependent studies of TiN films in vacuum. The thermal expansion coefficient of the TiN thin film was determined to be 10.27  ×  10‑6 °C‑1. At higher temperatures, the TiN thin film gradually loses its metallic characteristics and has weaker optical absorption, impairing its plasmonic performance. In addition, a sharp increase in film thickness was observed at the same time. Changes in the optical properties and film thickness with temperatures above 200 °C were revealed to result from TiN oxidation in air. For the stability of TiN-based plasmonic devices, operation temperatures of lower than 200 °C, or measures to prevent oxidation, are required. The present study is important to fundamental physics and technological applications of TiN thin films.

  20. Long-Range Correlations of Global Sea Surface Temperature

    PubMed Central

    Jiang, Lei; Zhao, Xia; Wang, Lu

    2016-01-01

    Scaling behaviors of the global monthly sea surface temperature (SST) derived from 1870–2009 average monthly data sets of Hadley Centre Sea Ice and SST (HadISST) are investigated employing detrended fluctuation analysis (DFA). The global SST fluctuations are found to be strong positively long-range correlated at all pertinent time-intervals. The value of scaling exponent is larger in the tropics than those in the intermediate latitudes of the northern and southern hemispheres. DFA leads to the scaling exponent α = 0.87 over the globe (60°S~60°N), northern hemisphere (0°N~60°N), and southern hemisphere (0°S~60°S), α = 0.84 over the intermediate latitude of southern hemisphere (30°S~60°S), α = 0.81 over the intermediate latitude of northern hemisphere (30°N~60°N) and α = 0.90 over the tropics 30°S~30°N [fluctuation F(s) ~ sα], which the fluctuations of monthly SST anomaly display long-term correlated behaviors. Furthermore, the larger the standard deviation is, the smaller long-range correlations (LRCs) of SST in the corresponding regions, especially in three distinct upwelling areas. After the standard deviation is taken into account, an index χ = α * σ is introduced to obtain the spatial distributions of χ. There exists an obvious change of global SST in central east and northern Pacific and the northwest Atlantic. This may be as a clue on predictability of climate and ocean variabilities. PMID:27100397

  1. Long-Range Correlations of Global Sea Surface Temperature.

    PubMed

    Jiang, Lei; Zhao, Xia; Wang, Lu

    2016-01-01

    Scaling behaviors of the global monthly sea surface temperature (SST) derived from 1870-2009 average monthly data sets of Hadley Centre Sea Ice and SST (HadISST) are investigated employing detrended fluctuation analysis (DFA). The global SST fluctuations are found to be strong positively long-range correlated at all pertinent time-intervals. The value of scaling exponent is larger in the tropics than those in the intermediate latitudes of the northern and southern hemispheres. DFA leads to the scaling exponent α = 0.87 over the globe (60°S~60°N), northern hemisphere (0°N~60°N), and southern hemisphere (0°S~60°S), α = 0.84 over the intermediate latitude of southern hemisphere (30°S~60°S), α = 0.81 over the intermediate latitude of northern hemisphere (30°N~60°N) and α = 0.90 over the tropics 30°S~30°N [fluctuation F(s) ~ sα], which the fluctuations of monthly SST anomaly display long-term correlated behaviors. Furthermore, the larger the standard deviation is, the smaller long-range correlations (LRCs) of SST in the corresponding regions, especially in three distinct upwelling areas. After the standard deviation is taken into account, an index χ = α * σ is introduced to obtain the spatial distributions of χ. There exists an obvious change of global SST in central east and northern Pacific and the northwest Atlantic. This may be as a clue on predictability of climate and ocean variabilities.

  2. Opportunities to Reduce Air-Conditioning Loads Through Lower Cabin Soak Temperatures

    SciTech Connect

    Farrington, R.; Cuddy, M.; Keyser, M.; Rugh, J.

    1999-07-12

    Air-conditioning loads can significantly reduce electric vehicle (EV) range and hybrid electric vehicle (HEV) fuel economy. In addition, a new U. S. emissions procedure, called the Supplemental Federal Test Procedure (SFTP), has provided the motivation for reducing the size of vehicle air-conditioning systems in the United States. The SFTP will measure tailpipe emissions with the air-conditioning system operating. If the size of the air-conditioning system is reduced, the cabin soak temperature must also be reduced, with no penalty in terms of passenger thermal comfort. This paper presents the impact of air-conditioning on EV range and HEV fuel economy, and compares the effectiveness of advanced glazing and cabin ventilation. Experimental and modeled results are presented.

  3. Soil temperature prediction from air temperature for alluvial soils in lower Indo-Gangetic plain

    NASA Astrophysics Data System (ADS)

    Barman, D.; Kundu, D. K.; Pal, Soumen; Pal, Susanto; Chakraborty, A. K.; Jha, A. K.; Mazumdar, S. P.; Saha, R.; Bhattacharyya, P.

    2017-01-01

    Soil temperature is an important factor in biogeochemical processes. On-site monitoring of soil temperature is limited in spatiotemporal scale as compared to air temperature data inventories due to various management difficulties. Therefore, empirical models were developed by taking 30-year long-term (1985-2014) air and soil temperature data for prediction of soil temperatures at three depths (5, 15, 30 cm) in morning (0636 Indian standard time) and afternoon (1336 Indian standard time) for alluvial soils in lower Indo-Gangetic plain. At 5 cm depth, power and exponential regression models were best fitted for daily data in morning and afternoon, respectively, but it was reverse at 15 cm. However, at 30 cm, exponential models were best fitted for both the times. Regression analysis revealed that in morning for all three depths and in afternoon for 30 cm depth, soil temperatures (daily, weekly, and monthly) could be predicted more efficiently with the help of corresponding mean air temperature than that of maximum and minimum. However, in afternoon, prediction of soil temperature at 5 and 15 cm depths were more precised for all the time intervals when maximum air temperature was used, except for weekly soil temperature at 15 cm, where the use of mean air temperature gave better prediction.

  4. The upper explosion limit of lower alkanes and alkenes in air at elevated pressures and temperatures.

    PubMed

    Van den Schoor, F; Verplaetsen, F

    2006-01-16

    The upper explosion limit (UEL) of ethane-air, propane-air, n-butane-air, ethylene-air and propylene-air mixtures is determined experimentally at initial pressures up to 30 bar and temperatures up to 250 degrees C. The experiments are performed in a closed spherical vessel with an internal diameter of 200 mm. The mixtures are ignited by fusing a coiled tungsten wire, placed at the centre of the vessel, by electric current. Flame propagation is said to have taken place if there is a pressure rise of at least 1% of the initial pressure after ignition of the mixture. In the pressure-temperature range investigated, a linear dependence of UEL on temperature and a bilinear dependence on pressure are found except in the vicinity of the auto-ignition range. A comparison of the UEL data of the lower alkanes shows that the UEL expressed as equivalence ratio (the actual fuel/air ratio divided by the stoichiometric fuel/air ratio) increases with increasing carbon number in the homologous series of alkanes.

  5. On the Trend of the Annual Mean, Maximum, and Minimum Temperature and the Diurnal Temperature Range in the Armagh Observatory, Northern Ireland, Dataset, 1844 -2012

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    2013-01-01

    Examined are the annual averages, 10-year moving averages, decadal averages, and sunspot cycle (SC) length averages of the mean, maximum, and minimum surface air temperatures and the diurnal temperature range (DTR) for the Armagh Observatory, Northern Ireland, during the interval 1844-2012. Strong upward trends are apparent in the Armagh surface-air temperatures (ASAT), while a strong downward trend is apparent in the DTR, especially when the ASAT data are averaged by decade or over individual SC lengths. The long-term decrease in the decadaland SC-averaged annual DTR occurs because the annual minimum temperatures have risen more quickly than the annual maximum temperatures. Estimates are given for the Armagh annual mean, maximum, and minimum temperatures and the DTR for the current decade (2010-2019) and SC24.

  6. Carbon nanotube dry adhesives with temperature-enhanced adhesion over a large temperature range

    NASA Astrophysics Data System (ADS)

    Xu, Ming; Du, Feng; Ganguli, Sabyasachi; Roy, Ajit; Dai, Liming

    2016-11-01

    Conventional adhesives show a decrease in the adhesion force with increasing temperature due to thermally induced viscoelastic thinning and/or structural decomposition. Here, we report the counter-intuitive behaviour of carbon nanotube (CNT) dry adhesives that show a temperature-enhanced adhesion strength by over six-fold up to 143 N cm-2 (4 mm × 4 mm), among the strongest pure CNT dry adhesives, over a temperature range from -196 to 1,000 °C. This unusual adhesion behaviour leads to temperature-enhanced electrical and thermal transports, enabling the CNT dry adhesive for efficient electrical and thermal management when being used as a conductive double-sided sticky tape. With its intrinsic thermal stability, our CNT adhesive sustains many temperature transition cycles over a wide operation temperature range. We discover that a `nano-interlock' adhesion mechanism is responsible for the adhesion behaviour, which could be applied to the development of various dry CNT adhesives with novel features.

  7. Carbon nanotube dry adhesives with temperature-enhanced adhesion over a large temperature range

    PubMed Central

    Xu, Ming; Du, Feng; Ganguli, Sabyasachi; Roy, Ajit; Dai, Liming

    2016-01-01

    Conventional adhesives show a decrease in the adhesion force with increasing temperature due to thermally induced viscoelastic thinning and/or structural decomposition. Here, we report the counter-intuitive behaviour of carbon nanotube (CNT) dry adhesives that show a temperature-enhanced adhesion strength by over six-fold up to 143 N cm−2 (4 mm × 4 mm), among the strongest pure CNT dry adhesives, over a temperature range from −196 to 1,000 °C. This unusual adhesion behaviour leads to temperature-enhanced electrical and thermal transports, enabling the CNT dry adhesive for efficient electrical and thermal management when being used as a conductive double-sided sticky tape. With its intrinsic thermal stability, our CNT adhesive sustains many temperature transition cycles over a wide operation temperature range. We discover that a ‘nano-interlock' adhesion mechanism is responsible for the adhesion behaviour, which could be applied to the development of various dry CNT adhesives with novel features. PMID:27849052

  8. Correlation of air temperature above water-air sections with the forecasted low level clouds

    NASA Astrophysics Data System (ADS)

    Huseynov, N. Sh.; Malikov, B. M.

    2009-04-01

    As a case study approach the development of low clouds forecasting methods in correlation with air temperature transformational variations on the sections "water-air" is surveyed. It was evident, that transformational variations of air temperature mainly depend on peculiarities and value of advective variations of temperature. DT is the differences of initial temperature on section water-air in started area, from contrast temperature of water surface along a trajectory of movement of air masses and from the temperature above water surface in a final point of a trajectory. Main values of transformational variations of air temperature at advection of a cold masses is 0.530C•h, and at advection of warm masses is -0.370C•h. There was dimensionless quantity K determined and implemented into practice which was characterized with difference of water temperature in forecasting point and air temperature in an initial point in the ratio of dew-points deficiency at the forecasting area. It follows, that the appropriate increasing or decreasing of K under conditions of cold and warm air masses advection, contributes decreasing of low clouds level. References: Abramovich K.G.: Conditions of development and forecasting of low level clouds. vol. #78, 124 pp., Hydrometcenter USSR 1973. Abramovich K.G.: Variations of low clouds level // Meteorology and Hydrology, vol. # 5, 30-41, Moscow, 1968. Budiko M.I.: Empirical assessment of climatic changes toward the end of XX century // Meteorology and Hydrology, vol. #12, 5-13, Moscow, 1999. Buykov M.V.: Computational modeling of daily evolutions of boundary layer of atmosphere at the presence of clouds and fog // Meteorology and Hydrology, vol. # 4, 35-44, Moscow, 1981. Huseynov N.Sh. Transformational variations of air temperature above Caspian Sea / Proceedings of Conference On Climate And Protection of Environment, 118-120, Baku, 1999. Huseynov N.Sh.: Consideration of advective and transformational variations of air temperature in

  9. Dependence of radon levels in Postojna Cave on outside air temperature

    NASA Astrophysics Data System (ADS)

    Gregorič, A.; Zidanšek, A.; Vaupotič, J.

    2011-05-01

    Postojna Cave is the largest of 21 show caves in Slovenia. The radon concentration there was measured continuously in the Great Mountain hall from July 2005 to October 2009 and ranged from about 200 Bq m-3 in winter to about 3 kBq m-3 in summer. The observed seasonal pattern of radon concentration is governed by air movement due to the difference in external and internal air densities, controlled mainly by air temperature. The cave behaves as a large chimney and in the cold period, the warmer cave air is released vertically through cracks and fissures to the colder outside atmosphere, enabling the inflow of fresh air with low radon levels. In summer the ventilation is minimal or reversed and the air flows from the higher to the lower openings of the cave. Our calculations have shown that the effect of the difference between outside and cave air temperatures on radon concentration is delayed for four days, presumably because of the distance of the measurement point from the lower entrance (ca. 2 km). A model developed for predicting radon concentration on the basis of outside air temperature has been checked and found to be successful.

  10. Heat tolerance of higher plants cenosis to damaging air temperatures

    NASA Astrophysics Data System (ADS)

    Ushakova, Sofya; Shklavtsova, Ekaterina

    Designing sustained biological-technical life support systems (BTLSS) including higher plants as a part of a photosynthesizing unit, it is important to foresee the multi species cenosis reaction on either stress-factors. Air temperature changing in BTLSS (because of failure of a thermoregulation system) up to the values leading to irreversible damages of photosynthetic processes is one of those factors. However, it is possible to increase, within the certain limits, the plant cenosis tolerance to the unfavorable temperatures’ effect due to the choice of the higher plants possessing resistance both to elevated and to lowered air temperatures. Besides, the plants heat tolerance can be increased when subjecting them during their growing to the hardening off temperatures’ effect. Thus, we have come to the conclusion that it is possible to increase heat tolerance of multi species cenosis under the damaging effect of air temperature of 45 (°) СC.

  11. Hydrogen-atmosphere induction furnace has increased temperature range

    NASA Technical Reports Server (NTRS)

    Caves, R. M.; Gresslin, C. H.

    1966-01-01

    Improved hydrogen-atmosphere induction furnace operates at temperatures up to 5,350 deg F. The furnace heats up from room temperature to 4,750 deg F in 30 seconds and cools down to room temperature in 2 minutes.

  12. AIRS Sea Surface Temperature and Pacific Decadal Oscillation

    NASA Astrophysics Data System (ADS)

    Chen, L. L.

    2015-12-01

    Atmospheric Infrared Sounder (AIRS) has been providing necessary measurements for long term atmospheric and surface processes aboard NASA' s Aqua polar orbiter since May 2002. Here, we use time series of AIRS sea surface temperature (SST) anomalies to show the time evolution of Pacific Decadal Oscillation (PDO) in the Gulf of Alaska (lon:-144.5, lat:54.5) from 2003 to 2014. PDO is connected to the first mode of North Pacific SST variability and is tele-connected to ENSO in the tropics. Further analysis of AIRS data can provide clarification of Pacific climate variability.

  13. Passive radiative cooling below ambient air temperature under direct sunlight.

    PubMed

    Raman, Aaswath P; Anoma, Marc Abou; Zhu, Linxiao; Rephaeli, Eden; Fan, Shanhui

    2014-11-27

    Cooling is a significant end-use of energy globally and a major driver of peak electricity demand. Air conditioning, for example, accounts for nearly fifteen per cent of the primary energy used by buildings in the United States. A passive cooling strategy that cools without any electricity input could therefore have a significant impact on global energy consumption. To achieve cooling one needs to be able to reach and maintain a temperature below that of the ambient air. At night, passive cooling below ambient air temperature has been demonstrated using a technique known as radiative cooling, in which a device exposed to the sky is used to radiate heat to outer space through a transparency window in the atmosphere between 8 and 13 micrometres. Peak cooling demand, however, occurs during the daytime. Daytime radiative cooling to a temperature below ambient of a surface under direct sunlight has not been achieved because sky access during the day results in heating of the radiative cooler by the Sun. Here, we experimentally demonstrate radiative cooling to nearly 5 degrees Celsius below the ambient air temperature under direct sunlight. Using a thermal photonic approach, we introduce an integrated photonic solar reflector and thermal emitter consisting of seven layers of HfO2 and SiO2 that reflects 97 per cent of incident sunlight while emitting strongly and selectively in the atmospheric transparency window. When exposed to direct sunlight exceeding 850 watts per square metre on a rooftop, the photonic radiative cooler cools to 4.9 degrees Celsius below ambient air temperature, and has a cooling power of 40.1 watts per square metre at ambient air temperature. These results demonstrate that a tailored, photonic approach can fundamentally enable new technological possibilities for energy efficiency. Further, the cold darkness of the Universe can be used as a renewable thermodynamic resource, even during the hottest hours of the day.

  14. Range Environmental Assessment Overland Air Operations, Eglin Air Force Base, Florida

    DTIC Science & Technology

    2014-11-12

    600 Tampa, FL 33607 November 2014 Printed on recycled paper Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the...and Rocket/Jet Assisted Takeoff (RATO/JATO) bottles . The Air Force proposes to authorize and implement a new level of activity for Eglin overland...powered portions (propellants) of missiles, bombs, flares, and RATO/JATO bottles . Eglin overland air operations do not involve bombs, missiles, ordnance

  15. Thermodynamic and transport combustion properties of hydrocarbons with air. Part 4: Compositions corresponding to Rankine temperature schedules in part 3

    NASA Technical Reports Server (NTRS)

    Gordon, S.

    1982-01-01

    The equilibrium compositions corresponding to the thermodynamic and transport combustion properties for a wide range of conditions for the reaction of hydrocarbons with air are presented. The compositions presented correspond to Rankine temperature schedules.

  16. Preserving Range and Airspace Access for the Air Force Mission: Striving for a Strategic Vantage Point

    DTIC Science & Technology

    2011-01-01

    turbines on land now set aside for Air Force use, and the increasing demand for airspace to accom- modate the growth in civilian air traffic. • next...to ranges, energy development that seeks to place wind turbines on land now set aside for Air Force use, and increasing demand for sufficient... turbine towers may create a hazard to low-flying aircraft and thus preclude low-level training. Wind turbines tend to be located in gaps with higher

  17. High temperature transport properties of air

    NASA Technical Reports Server (NTRS)

    Levin, E.; Partridge, Harry; Stallcop, J. R.

    1987-01-01

    A general computer code was developed to allow calculation of atom-atom and ion-atom transport collision integrals from accurate potential energy curves described by a set of discrete data points for a broad range of scattering conditions. This code is based upon semiclassical approximations that properly account for quantum mechanical behavior such as tunneling effects near a barrier maximum, resonance charge exchange, and nuclear symmetry effects. Transport collision integrals were determined for N-N, O-O, N(+)-N, and O(+)-O interactions from complete sets of accurate potential functions derived from combined experimental and ab initio structure calculations. For the O-O case, this includes results for excited states. The calculated values of the N(+)-N and O(+)-O resonance charge exchange cross section Q(ex) agree well with measurements from beam experiment that are available at high energies where the diffusion cross section Q(d) satisfies Q(d) approximately equal to 2Q(ex).

  18. Effects of air flow directions on composting process temperature profile

    SciTech Connect

    Kulcu, Recep; Yaldiz, Osman

    2008-07-01

    In this study, chicken manure mixed with carnation wastes was composted by using three different air flow directions: R1-sucking (downward), R2-blowing (upward) and R3-mixed. The aim was to find out the most appropriate air flow direction type for composting to provide more homogenous temperature distribution in the reactors. The efficiency of each aeration method was evaluated by monitoring the evolution of parameters such as temperature, moisture content, CO{sub 2} and O{sub 2} ratio in the material and dry material losses. Aeration of the reactors was managed by radial fans. The results showed that R3 resulted in a more homogenous temperature distribution and high dry material loss throughout the composting process. The most heterogeneous temperature distribution and the lowest dry material loss were obtained in R2.

  19. The comparative performance of an aviation engine at normal and high inlet air temperatures

    NASA Technical Reports Server (NTRS)

    Gardiner, Arthur W; Schey, Oscar W

    1928-01-01

    This report presents some results obtained during an investigation to determine the effect of high inlet air temperature on the performance of a Liberty 12 aviation engine. The purpose of this investigation was to ascertain, for normal service carburetor adjustments and a fixed ignition advance, the relation between power and temperature for the range of carburetor air temperatures that may be encountered when supercharging to sea level pressure at altitudes of over 20,000 feet and without intercooling when using plain aviation gasoline and mixtures of benzol and gasoline. The results show that for the conditions of test, both the brake and indicated power decrease with increase in air temperature at a faster rate than given by the theoretical assumption that power varies inversely as the square root of the absolute temperature. On a brake basis, the order of the difference in power for a temperature difference of 120 degrees F. Is 3 to 5 per cent. The observed relation between power and temperature when using the 30-70 blend was found to be linear. But, although these differences are noted, the above theoretical assumption may be considered as generally applicable except where greater precision over a wide range of temperatures is desired, in which case it appears necessary to test the particular engine under the given conditions. (author)

  20. An Optimization Approach to Analyzing the Effect of Supply Water and Air Temperatures in Planning an Air Conditioning System

    NASA Astrophysics Data System (ADS)

    Karino, Naoki; Shiba, Takashi; Yokoyama, Ryohei; Ito, Koichi

    In planning an air conditioning system, supply water and air temperatures are important factors from the viewpoint of cost reduction. For example, lower temperature supply water and air reduce the coefficient of performance of a refrigeration machine, and increase the thickness of heat insulation material. However, they enable larger temperature differences, and reduce equipment sizes and power demand. The purposes of this paper are to propose an optimal planning method for a cold air distribution system, and to analyze the effect of supply water and air temperatures on the long-term economics through a numerical study for an office building. As a result, it is shown that the proposed method effectively determines supply water and air temperatures for a cold air distribution system, and that the influence of supply air temperature is larger than that of supply water temperature on the long-term economics.

  1. Arctic air may become cleaner as temperatures rise

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2011-10-01

    The air in the Arctic is cleaner during summer than during winter. Previous studies have shown that for light-scattering pollutants, this seasonal cycle is due mainly to summer precipitation removing pollutants from the air during atmospheric transport from midlatitude industrial and agricultural sources. With new measurements from Barrow, Alaska, and Alert, Nunavut, Canada, Garrett et al. extended previous research to show that light-absorbing aerosols such as black carbon are also efficiently removed by seasonal precipitation. Precipitation removes these particles from the air most efficiently at high humidities and relatively warm temperatures, suggesting that as the Arctic gets warmer and wetter in the future, the air and snow might also become cleaner.

  2. The Temperature Dependence of a Large Dynamic Range Photodetector Structure

    DTIC Science & Technology

    1991-12-01

    to achieve a logarithmic steady state response. This paper analyzes the temperature dependence of the circuit operation and presents experimental results demonstrating the capabilities and limitations of the model.

  3. Dynamic Stiffness and Damping Characteristics of a High-Temperature Air Foil Journal Bearing

    NASA Technical Reports Server (NTRS)

    Howard, Samuel A.; DellaCorte, Christopher; Valco, Mark J.; Prahl, Joseph M.; Heshmat, Hooshang

    2001-01-01

    Using a high-temperature optically based displacement measurement system, a foil air bearing's stiffness and damping characteristics were experimentally determined. Results were obtained over a range of modified Sommerfeld Number from 1.5E6 to 1.5E7, and at temperatures from 25 to 538 C. An Experimental procedure was developed comparing the error in two curve fitting functions to reveal different modes of physical behavior throughout the operating domain. The maximum change in dimensionless stiffness was 3.0E-2 to 6.5E-2 over the Sommerfeld Number range tested. Stiffness decreased with temperature by as much as a factor of two from 25 to 538 C. Dimensionless damping was a stronger function of Sommerfeld Number ranging from 20 to 300. The temperature effect on damping being more qualitative, showed the damping mechanism shifted from viscous type damping to frictional type as temperature increased.

  4. Influence of ambient temperature and diurnal temperature range on incidence of cardiac arrhythmias

    NASA Astrophysics Data System (ADS)

    Kim, Jayeun; Kim, Ho

    2017-03-01

    We investigated the association between ambient temperature and diurnal temperature range (DTR) and the exacerbation of arrhythmia symptoms, using data from 31,629 arrhythmia-related emergency department (ED) visits in Seoul, Korea. Linear regression analyses with allowances for over-dispersion were applied to temperature variables and ED visits, adjusted for various environmental factors. The effects were expressed as percentage changes in the risk of arrhythmia-related ED visits up to 5 days later, with 95 % confidence intervals (CI), per 1 °C increase in DTR and 1 °C decrease in mean temperature. The overall risk of ED visits increased by 1.06 % (95 % CI 0.39 %, 1.73 %) for temperature and by 1.84 % (0.34, 3.37 %) for DTR. A season-specific effect was detected for temperature during both fall (1.18 % [0.01, 2.37 %]) and winter (0.87 % [0.07, 1.67 %]), and for DTR during spring (3.76 % [0.34, 7.29 %]). Females were more vulnerable, with 1.57 % [0.56, 2.59 %] and 3.84 % [1.53, 6.20 %] for the changes in temperature and DTR, respectively. An age-specific effect was detected for DTR, with 3.13 % [0.95, 5.36 %] for age ≥ 65 years, while a greater increased risk with temperature decrease was observed among those aged <65 (1.08 % [0.17, 2.00 %]) than among those aged ≥65 (1.02 % [0.06, 1.99 %]). Cardiac arrest was inversely related with temperature (1.61 % [0.46, 2.79 %]), while other cardiac arrhythmias depended more on the change in DTR (4.72 % [0.37, 9.26 %]). These findings provide evidence that low-temperature and elevated DTR influence the occurrence of arrhythmia exacerbations or symptoms, suggesting a possible strategy for reducing risk by encouraging vulnerable populations to minimize exposure.

  5. Influence of ambient temperature and diurnal temperature range on incidence of cardiac arrhythmias

    NASA Astrophysics Data System (ADS)

    Kim, Jayeun; Kim, Ho

    2016-08-01

    We investigated the association between ambient temperature and diurnal temperature range (DTR) and the exacerbation of arrhythmia symptoms, using data from 31,629 arrhythmia-related emergency department (ED) visits in Seoul, Korea. Linear regression analyses with allowances for over-dispersion were applied to temperature variables and ED visits, adjusted for various environmental factors. The effects were expressed as percentage changes in the risk of arrhythmia-related ED visits up to 5 days later, with 95 % confidence intervals (CI), per 1 °C increase in DTR and 1 °C decrease in mean temperature. The overall risk of ED visits increased by 1.06 % (95 % CI 0.39 %, 1.73 %) for temperature and by 1.84 % (0.34, 3.37 %) for DTR. A season-specific effect was detected for temperature during both fall (1.18 % [0.01, 2.37 %]) and winter (0.87 % [0.07, 1.67 %]), and for DTR during spring (3.76 % [0.34, 7.29 %]). Females were more vulnerable, with 1.57 % [0.56, 2.59 %] and 3.84 % [1.53, 6.20 %] for the changes in temperature and DTR, respectively. An age-specific effect was detected for DTR, with 3.13 % [0.95, 5.36 %] for age ≥ 65 years, while a greater increased risk with temperature decrease was observed among those aged <65 (1.08 % [0.17, 2.00 %]) than among those aged ≥65 (1.02 % [0.06, 1.99 %]). Cardiac arrest was inversely related with temperature (1.61 % [0.46, 2.79 %]), while other cardiac arrhythmias depended more on the change in DTR (4.72 % [0.37, 9.26 %]). These findings provide evidence that low-temperature and elevated DTR influence the occurrence of arrhythmia exacerbations or symptoms, suggesting a possible strategy for reducing risk by encouraging vulnerable populations to minimize exposure.

  6. Local air temperature tolerance: a sensible basis for estimating climate variability

    NASA Astrophysics Data System (ADS)

    Kärner, Olavi; Post, Piia

    2016-11-01

    The customary representation of climate using sample moments is generally biased due to the noticeably nonstationary behaviour of many climate series. In this study, we introduce a moment-free climate representation based on a statistical model fitted to a long-term daily air temperature anomaly series. This model allows us to separate the climate and weather scale variability in the series. As a result, the climate scale can be characterized using the mean annual cycle of series and local air temperature tolerance, where the latter is computed using the fitted model. The representation of weather scale variability is specified using the frequency and the range of outliers based on the tolerance. The scheme is illustrated using five long-term air temperature records observed by different European meteorological stations.

  7. The effect of air temperature on the sappan wood extract drying

    NASA Astrophysics Data System (ADS)

    Djaeni, M.; Triyastuti, M. S.; Asiah, N.; Annisa, A. N.; Novita, D. A.

    2015-12-01

    The sappan wood extract contain natural colour called brazilin that can be used as a food colouring and antioxidant. The product is commonly found as a dry extract powder for consummer convenience. The spray dryer with air dehumidification can be an option to retain the colour and antioxidant agent. This paper discusses the effect of air temperature on sappan wood extract drying that was mixed with maltodextrin. As responses, the particle size, final moisture content, and extract solubility degradation were observed. In all cases, the process conducted in temperature ranging 90 - 110°C can retain the brazilin quality as seen in solubility and particle size. In addition, the sappan wood extract can be fully dried with moisture content below 2%. Moreover, with the increase of air temperature, the particle size of dry extract can be smaller.

  8. Environmental Assessment for Nellis Air Force Range Complex Fiber Optic Line Route from Indian Springs AFAF, Clark County to Cedar Pass Facility, NAFR North Range Nye County, Nevada

    DTIC Science & Technology

    1998-01-01

    Nevada Test Site and Nellis Air Force Range. Dr. Pippin was responsible for the cultural/ historical survey and cultural/ historical resources materials...transmits data generated by Air Force train ing, testing and evaluation programs related to air- and ground-based systems. A FOL network already...transmit data generated by Air Force training, testing and evaluation programs related to air- and ground-based systems. The proposed action would provide

  9. Discovery about temperature fluctuations in turbulent air flows

    NASA Astrophysics Data System (ADS)

    1985-02-01

    The law of spatial fluctuations of temperature in a turbulent flow in the atmosphere was studied. The turbulent movement of air in the atmosphere manifests itself in random changes in wind velocity and in the dispersal of smoke. If a miniature thermometer with sufficient sensitivity and speed of response were placed in a air flow, its readings would fluctuate chaotically against the background of average temperature. This is Characteristic of practically every point of the flow. The temperature field forms as a result of the mixing of the air. A method using the relation of the mean square of the difference in temperatures of two points to the distance between these points as the structural characteristic of this field was proposed. It was found that the dissipation of energy in a flow and the equalization of temperatures are connected with the breaking up of eddies in a turbulent flow into smaller ones. Their energy in turn is converted into heat due to the viscosity of the medium. The law that has been discovered makes for a much broader field of application of physical methods of analyzing atmospheric phenomena.

  10. Microwave temperature profiler for clear air turbulence prediction

    NASA Technical Reports Server (NTRS)

    Gary, Bruce L. (Inventor)

    1992-01-01

    A method is disclosed for determining Richardson Number, Ri, or its reciprocal, RRi, for clear air prediction using measured potential temperature and determining the vertical gradient of potential temperature, d(theta)/dz. Wind vector from the aircraft instrumentation versus potential temperature, dW/D(theta), is determined and multiplies by d(theta)/dz to obtain dW/dz. Richardson number or its reciprocal is then determined from the relationship Ri = K(d theta)/dz divided by (dW/dz squared) for use in detecting a trend toward a threshold value for the purpose of predicting clear air turbulence. Other equations for this basic relationship are disclosed together with the combination of other atmospheric observables using multiple regression techniques.

  11. CARS Temperature and Species Measurements For Air Vehicle Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Danehy, Paul M.; Gord, James R.; Grisch, Frederic; Klimenko, Dmitry; Clauss, Walter

    2005-01-01

    The coherent anti-Stokes Raman spectroscopy (CARS) method has recently been used in the United States and Europe to probe several different types of propulsion systems for air vehicles. At NASA Langley Research Center in the United States, CARS has been used to simultaneously measure temperature and the mole fractions of N2, O2 and H2 in a supersonic combustor, representative of a scramjet engine. At Wright- Patterson Air Force Base in the United States, CARS has been used to simultaneously measure temperature and mole fractions of N2, O2 and CO2, in the exhaust stream of a liquid-fueled, gas-turbine combustor. At ONERA in France and the DLR in Germany researchers have used CARS to measure temperature and species concentrations in cryogenic LOX-H2 rocket combustion chambers. The primary aim of these measurements has been to provide detailed flowfield information for computational fluid dynamics (CFD) code validation.

  12. AIM-120 Advanced Medium Range Air-to-Air Missile (AMRAAM)

    DTIC Science & Technology

    2013-12-01

    Cost BA - Budget Authority/Budget Activity BY - Base Year DAMIR - Defense Acquisition Management Information Retrieval Dev Est - Development Estimate...lilA (DAB) DAE Program Review Start Production Deliveries Complete DAOT&E (Air Force) Complete IOT &E!Captive Ca ... Initial EQuipage Milestone... IOT &E OCT 1983 N/A N/A OCT 1983 Certification FEB 1986 FEB 1986 AUG 1986 FEB 1986 Milestone IIIA (DAB) JUN 1987 JUN 1987 DEC 1987 JUN 1987 DAE

  13. Peroxy radicals and ozone photochemistry in air masses undergoing long-range transport

    NASA Astrophysics Data System (ADS)

    Parker, A. E.; Monks, P. S.; Jacob, M. J.; Penkett, S. A.; Lewis, A. C.; Stewart, D. J.; Whalley, L. K.; Methven, J.; Stohl, A.

    2009-09-01

    Concentrations of peroxy radicals (HO2+ΣiRiO2) in addition to other trace gases were measured onboard the UK Meteorological Office/Natural Environment Research Council British Aerospace 146-300 atmospheric research aircraft during the Intercontinental Transport of Ozone and Precursors (ITOP) campaign based at Horta Airport, Faial, Azores (38.58° N, 28.72° W) in July/August 2004. The overall peroxy radical altitude profile displays an increase with altitude that is likely to have been impacted by the effects of long-range transport. The peroxy radical altitude profile for air classified as of marine origin shows no discernable altitude profile. A range of air-masses were intercepted with varying source signatures, including those with aged American and Asian signatures, air-masses of biomass burning origin, and those that originated from the east coast of the United States. Enhanced peroxy radical concentrations have been observed within this range of air-masses indicating that long-range transported air-masses traversing the Atlantic show significant photochemical activity. The net ozone production at clear sky limit is in general negative, and as such the summer mid-Atlantic troposphere is at limit net ozone destructive. However, there is clear evidence of positive ozone production even at clear sky limit within air masses undergoing long-range transport, and during ITOP especially between 5 and 5.5 km, which in the main corresponds to a flight that extensively sampled air with a biomass burning signature. Ozone production was NOx limited throughout ITOP, as evidenced by a good correlation (r2=0.72) between P(O3) and NO. Strong positive net ozone production has also been seen in varying source signature air-masses undergoing long-range transport, including but not limited to low-level export events, and export from the east coast of the United States.

  14. Impacts of Lowered Urban Air Temperatures on Precursor Emission and Ozone Air Quality.

    PubMed

    Taha, Haider; Konopacki, Steven; Akbari, Hashem

    1998-09-01

    Meteorological, photochemical, building-energy, and power plant simulations were performed to assess the possible precursor emission and ozone air quality impacts of decreased air temperatures that could result from implementing the "cool communities" concept in California's South Coast Air Basin (SoCAB). Two pathways are considered. In the direct pathway, a reduction in cooling energy use translates into reduced demand for generation capacity and, thus, reduced precursor emissions from electric utility power plants. In the indirect pathway, reduced air temperatures can slow the atmospheric production of ozone as well as precursor emission from anthropogenic and biogenic sources. The simulations suggest small impacts on emissions following implementation of cool communities in the SoCAB. In summer, for example, there can be reductions of up to 3% in NOx emissions from in-basin power plants. The photochemical simulations suggest that the air quality impacts of these direct emission reductions are small. However, the indirect atmospheric effects of cool communities can be significant. For example, ozone peak concentrations can decrease by up to 11% in summer and population-weighted exceedance exposure to ozone above the California and National Ambient Air Quality Standards can decrease by up to 11 and 17%, respectively. The modeling suggests that if these strategies are combined with others, such as mobile-source emission control, the improvements in ozone air quality can be substantial.

  15. The Effects of Air Pollution and Temperature on COPD

    PubMed Central

    Hansel, Nadia N.; McCormack, Meredith C.; Kim, Victor

    2016-01-01

    Chronic Obstructive Pulmonary Disease (COPD) affects 12–16 million people in the United States and is the third-leading cause of death. In developed countries, smoking is the greatest risk factor for the development of COPD, but other exposures also contribute to the development and progression of the disease. Several studies suggest, though are not definitive, that outdoor air pollution exposure is linked to the prevalence and incidence of COPD. Among individuals with COPD, outdoor air pollutants are associated with loss of lung function and increased respiratory symptoms. In addition, outdoor air pollutants are also associated with COPD exacerbations and mortality. There is much less evidence for the impact of indoor air on COPD, especially in developed countries in residences without biomass exposure. The limited existing data suggests that indoor particulate matter and nitrogen dioxide concentrations are linked to increased respiratory symptoms among patients with COPD. In addition, with the projected increases in temperature and extreme weather events in the context of climate change there has been increased attention to the effects of heat exposure. Extremes of temperature—both heat and cold—have been associated with increased respiratory morbidity in COPD. Some studies also suggest that temperature may modify the effect of pollution exposure and though results are not conclusive, understanding factors that may modify susceptibility to air pollution in patients with COPD is of utmost importance. PMID:26683097

  16. Wide temperature range testing with ROTEM coagulation analyses.

    PubMed

    Kander, Thomas; Brokopp, Jens; Friberg, Hans; Schött, Ulf

    2014-09-01

    Mild induced hypothermia is used for neuroprotection in patients successfully resuscitated after cardiac arrest. Temperature-dependent effects on rotational thromboelastometry (ROTEM(®)) assays with EXTEM(®), FIBTEM(®), or APTEM(®) in cardiac arrest patients have not previously been studied. Ten patients with out-of-hospital cardiac arrest who underwent induced hypothermia were studied during stable hypothermia at 33°C. ROTEM temperature effects on EXTEM, FIBTEM, and APTEM assays were studied at temperatures set between 30°C and 42°C. Citrated whole blood test tubes were incubated in temperature-adjusted heating blocks and then investigated at respective temperature in the temperature-adjusted ROTEM. The following variables were determined: clotting time (CT), clot formation time (CFT), α-angle, and maximum clot firmness (MCF). The results from hypo- and hyperthermia samples were compared with the samples incubated at 37°C using the Wilcoxon matched-pairs signed-rank test. A p-value of <0.05 was considered significant. CT-EXTEM(®) and CT-APTEM(®) were prolonged by hypothermia at 30°C (p<0.01 for both) and 33°C (p<0.05 for both). Hyperthermia at 42°C shortened CT-EXTEM (p<0.05) and CT-APTEM (p<0.01). CFT-EXTEM(®) and CFT-APTEM(®) were markedly prolonged by hypothermia at 30°C, 33°C, and 35°C (p<0.01 for all except CFT-EXTEM, 35°C [p<0.05]). The α-angle-EXTEM was markedly decreased at 30°C, 33°C, and 35°C (p<0.01) but increased at 40°C (p<0.05) and 42°C (p<0.01); α-angle-APTEM showed similar results. MCF was unchanged at different temperatures for all tests. ROTEM (EXTEM, FIBTEM, and APTEM assays) revealed a hypocoagulative response to in vitro-applied hypothermia in the blood of cardiac arrest patients reflected in the prolonged clot initiation and decreased clot propagation. Hyperthermia showed the opposite effects. Clot firmness was not affected by temperature.

  17. Influence of metallic vapours on thermodynamic and transport properties of two-temperature air plasma

    NASA Astrophysics Data System (ADS)

    Zhong, Linlin; Wang, Xiaohua; Cressault, Yann; Teulet, Philippe; Rong, Mingzhe

    2016-09-01

    The metallic vapours (i.e., copper, iron, and silver in this paper) resulting from walls and/or electrode surfaces can significantly affect the characteristics of air plasma. Different from the previous works assuming local thermodynamic equilibrium, this paper investigates the influence of metallic vapours on two-temperature (2 T) air plasma. The 2 T compositions of air contaminated by Cu, Fe, and Ag are first determined based on Saha's and Guldberg-Waage's laws. The thermodynamic properties (including mass density, specific enthalpy, and specific heat) are then calculated according to their definitions. After determining the collision integrals for each pair of species in air-metal mixtures using the newly published methods and source data, the transport coefficients (including electrical conductivity, viscosity, and thermal conductivity) are calculated for air-Cu, air-Fe, and air-Ag plasmas with different non-equilibrium degree θ (Te/Th). The influences of metallic contamination as well as non-equilibrium degree are discussed. It is found that copper, iron, and silver exist mainly in the form of Cu2, FeO, and AgO at low temperatures. Generally, the metallic vapours increase mass density at most temperatures, reduce the specific enthalpy and specific heat in the whole temperature range, and affect the transport properties remarkably from 5000 K to 20 000 K. The effect arising from the type of metals is little except for silver at certain temperatures. Besides, the departure from thermal equilibrium results in the delay of dissociation and ionization reactions, leading to the shift of thermodynamic and transport properties towards a higher temperature.

  18. Gap/silicon Tandem Solar Cell with Extended Temperature Range

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A. (Inventor)

    2006-01-01

    A two-junction solar cell has a bottom solar cell junction of crystalline silicon, and a top solar cell junction of gallium phosphide. A three (or more) junction solar cell has bottom solar cell junctions of silicon, and a top solar cell junction of gallium phosphide. The resulting solar cells exhibit improved extended temperature operation.

  19. Water temperature impacts water consumption by range cattle in winter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water consumption and DMI have been found to be positively correlated, which may interact with ingestion of cold water or grazed frozen forage due to transitory reductions in temperature of ruminal contents. The hypothesis underpinning the study explores the potential that cows provided warm drinkin...

  20. Climate change and river temperature sensitivity to warmer nighttime vs. warmer daytime air temperatures

    NASA Astrophysics Data System (ADS)

    Diabat, M.; Haggerty, R.; Wondzell, S. M.

    2011-12-01

    We investigated the July river temperature response to atmospheric warming over the diurnal cycle in a 36 km reach of the upper Middle Fork John Day River of Oregon, USA. The physical model Heat Source was calibrated and used to run 3 different cases of increased air temperature during July: 1) uniform increase over the whole day ("delta method"), 2) warmer daytime, and 3) warmer nighttime. All 3 cases had the same mean daily air temperatures - a 4 °C increase relative to 2002. Results show that the timing of air temperature increases has a significant effect on the magnitude, timing and duration of changes in water temperatures relative to current conditions. In all cases, river temperatures in the lower reach increased by at least 1.1 °C . For the delta case, water temperature increases never exceeded 2.3 °C. In contrast, under the warmer daytime case, water temperature increases exceeded 2.3 °C for 6.6 hours/day on average, with the largest increases occurring during mid-day. In the warmer night case the river temperature increases exceeded 2.3 °C for 4.3 hours/day on average with the largest increases occurring around midnight. In addition, an average increase of 4 °C in air temperature under the delta case increased the water temperature by an average of 1.9 °C uniformly during daytime and nighttime. Still, an average increase of 4 °C in air temperature under the warmer daytime case increased water temperature by an average of at least 1.6 °C during the daytime and by an average of up to 2.5 °C during the nighttime, while an average increase of 4 °C in air temperature under the warmer nighttime case increased the water temperature by an average of at least 1.4 °C during the nighttime and by an average of up to 2.4 °C during the daytime. The spatial response of temperature was different for each case. The lower 13 rkm warmed by at least 1.1 °C with the delta case, while only the lower 6 rkm warmed by at least 1.1 °C with the warmer daytime case

  1. Evaluating CMIP5 models using AIRS tropospheric air temperature and specific humidity climatology

    NASA Astrophysics Data System (ADS)

    Tian, Baijun; Fetzer, Eric J.; Kahn, Brian H.; Teixeira, Joao; Manning, Evan; Hearty, Thomas

    2013-01-01

    This paper documents the climatological mean features of the Atmospheric Infrared Sounder (AIRS) monthly mean tropospheric air temperature (ta, K) and specific humidity (hus, kg/kg) products as part of the Obs4MIPs project and compares them to those from NASA's Modern Era Retrospective analysis for Research and Applications (MERRA) for validation and 16 models from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) for CMIP5 model evaluation. MERRA is warmer than AIRS in the free troposphere but colder in the boundary layer with differences typically less than 1 K. MERRA is also drier (~10%) than AIRS in the tropical boundary layer but wetter (~30%) in the tropical free troposphere and the extratropical troposphere. In particular, the large MERRA-AIRS specific humidity differences are mainly located in the deep convective cloudy regions indicating that the low sampling of AIRS in the cloudy regions may be the main reason for these differences. In comparison to AIRS and MERRA, the sixteen CMIP5 models can generally reproduce the climatological features of tropospheric air temperature and specific humidity well, but several noticeable biases exist. The models have a tropospheric cold bias (around 2 K), especially in the extratropical upper troposphere, and a double-ITCZ problem in the troposphere from 1000 hPa to 300 hPa, especially in the tropical Pacific. The upper-tropospheric cold bias exists in the most (13 of 16) models, and the double-ITCZ bias is found in all 16 CMIP5 models. Both biases are independent of the reference dataset used (AIRS or MERRA).

  2. Record low surface air temperature at Vostok station, Antarctica

    NASA Astrophysics Data System (ADS)

    Turner, John; Anderson, Phil; Lachlan-Cope, Tom; Colwell, Steve; Phillips, Tony; Kirchgaessner, AméLie; Marshall, Gareth J.; King, John C.; Bracegirdle, Tom; Vaughan, David G.; Lagun, Victor; Orr, Andrew

    2009-12-01

    The lowest recorded air temperature at the surface of the Earth was a measurement of -89.2°C made at Vostok station, Antarctica, at 0245 UT on 21 July 1983. Here we present the first detailed analysis of this event using meteorological reanalysis fields, in situ observations and satellite imagery. Surface temperatures at Vostok station in winter are highly variable on daily to interannual timescales as a result of the great sensitivity to intrusions of maritime air masses as Rossby wave activity changes around the continent. The record low temperature was measured following a near-linear cooling of over 30 K over a 10 day period from close to mean July temperatures. The event occurred because of five specific conditions that arose: (1) the temperature at the core of the midtropospheric vortex was at a near-record low value; (2) the center of the vortex moved close to the station; (3) an almost circular flow regime persisted around the station for a week resulting in very little warm air advection from lower latitudes; (4) surface wind speeds were low for the location; and (5) no cloud or diamond dust was reported above the station for a week, promoting the loss of heat to space via the emission of longwave radiation. We estimate that should a longer period of isolation occur the surface temperature at Vostok could drop to around -96°C. The higher site of Dome Argus is typically 5-6 K colder than Vostok so has the potential to record an even lower temperature.

  3. Silicon device performance measurements to support temperature range enhancement

    NASA Technical Reports Server (NTRS)

    Bromstead, James; Weir, Bennett; Cosby, Melvin; Johnson, R. Wayne; Nelms, R. Mark; Askew, Ray

    1992-01-01

    Characterization results of a MOS controlled thyristor (MCTA60P60) are presented. This device is rated for 60A and for an anode to cathode voltage of -600 V. As discussed in the last report, the MCT failed during 500 V leakage tests at 200 C. In contrast to the BJT (bipolar junction transistor), MOSFET, and IGBT (insulated gate bipolar transistor) devices tested, the breakdown voltage of the MCT decreases significantly with increasing temperature.

  4. Silicon device performance measurements to support temperature range enhancement

    NASA Technical Reports Server (NTRS)

    Bromstead, James; Weir, Bennett; Johnson, R. Wayne; Askew, Ray

    1992-01-01

    Testing of the metal oxide semiconductor (MOS)-controlled thyristor (MCT) has uncovered a failure mechanism at elevated temperature. The failure appears to be due to breakdown of the gate oxide. Further testing is underway to verify the failure mode. Higher current level inverters were built to demonstrate 200 C operation of the N-MOSFET's and insulated-gate-bipolar transistors (IGBT's) and for life testing. One MOSFET failed early in testing. The origin of this failure is being studied. No IGBT's have failed. A prototype 28-to-42 V converter was built and is being tested at room temperature. The control loop is being finalized. Temperature stable, high value (10 micro-F) capacitors appear to be the limiting factor in the design at this time. In this application, the efficiency will be lower for the IGBT version due to the large V sub(cesat) (3.5-4 V) compared to the input voltage of 28 V. The MOSFET version should have higher efficiency; however, the MOSFET does not appear to be as robust at 200 C. Both versions are built for comparison.

  5. Effects of light intensity and air velocity on air temperature, water vapor pressure, and CO2 concentration inside a plant canopy under an artificial lighting condition.

    PubMed

    Kitaya, Y; Shibuya, T; Kozai, T; Kubota, C

    1998-01-01

    In order to characterize environmental variables inside a plant canopy under artificial lighting in the CELSS, we investigated the effects of light intensity and air velocity on air temperature, water vapor pressure, and CO2 concentration inside a plant canopy. Under a PPF of 500 micromoles m-2 s-1, air temperature was 2-3 degrees C higher, water vapor pressure was 0.6 kPa higher, and CO2 concentration was 25-35 micromoles mol-1 lower at heights ranging from 0 to 30 mm below the canopy than at a height 60 mm above the canopy. Increasing the PPF increased air temperature and water vapor pressure and decreased CO2 concentration inside the canopy. The air temperature was lower and the CO2 concentration was higher inside the canopy at an air velocity of 0.3 m s-1 than at an air velocity of 0.1 m s-1. The environmental variables inside the canopy under a high light intensity were characterized by higher air temperature, higher vapor pressure, and lower CO2 concentration than those outside the canopy.

  6. Temperature and Transpiration Resistances of Xanthium Leaves as Affected by Air Temperature, Humidity, and Wind Speed 1

    PubMed Central

    Drake, B. G.; Raschke, K.; Salisbury, F. B.

    1970-01-01

    Transpiration and temperatures of single, attached leaves of Xanthium strumarium L. were measured in high intensity white light (1.2 calories per square centimeter per minute on a surface normal to the radiation), with abundant water supply, at wind speeds of 90, 225, and 450 centimeters per second, and during exposure to moist and dry air. Partitioning of absorbed radiation between transpiration and convection was determined, and transpiration resistances were computed. Leaf resistances decreased with increasing temperature (down to a minimum of 0.36 seconds per centimeter). Silicone rubber replicas of leaf surfaces proved that the decrease was due to increased stomatal apertures. At constant air temperature, leaf resistances were higher in dry than in moist air with the result that transpiration varied less than would have been predicted on the basis of the water-vapor pressure difference between leaf and air. The dependence of stomatal conductance on temperature and moisture content of the air caused the following effects. At air temperatures below 35 C, average leaf temperatures were above air temperature by an amount dependent on wind velocity; increasing wind diminished transpiration. At air temperatures above 35 C, leaf temperatures were below air temperatures, and increasing wind markedly increased transpiration. Leaf temperatures equaled air temperature near 35 C at all wind speeds and in moist as well as in dry air. PMID:16657458

  7. Final Environmental Assessment for the Target Enhancement Railway At Avon Park Air Force Range, Florida

    DTIC Science & Technology

    2008-02-01

    dominated by various herbaceous wetland plants (Panicum tenerum, Xyris elliottii, Rhychospora tracyi, etc.) and St . Johns wort (Hypericum fasciculatum...Florida 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7...PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) Air Combat Command,Environmental Flight,Avon Park Air Force Range,FL,33825 8. PERFORMING ORGANIZATION

  8. Quantitative reconstruction of paleoclimate - Air and ground temperature tracking from Emigrant Pass Observatory

    NASA Astrophysics Data System (ADS)

    Chapman, D. S.; Bartlett, M. G.; Harris, R. N.

    2004-12-01

    Borehole temperature-depth profiles contain information about surface ground temperatures histories and provide a useful complement to proxy indicators of climate change. An inherent assumption in borehole temperature reconstructions is that air and ground temperatures are coupled through heat diffusion track each other at annual and longer periods. The Emigrant Pass Observatory (EPO), located in the Grouse Creek Mountains of northwestern Utah, is designed to test ground-air temperature tracking. Analyses of 10 years of observations at EPO demonstrate the following: 1) Ground temperatures track air temperatures at annual and longer periods exceptionally well at the site. Divergence between the observed temperatures at 1 m in the subsurface and air temperatures modeled as a boundary layer forcing is less than 0.04 K per annum. 2) Seasonal variations in incident solar radiation are ~200 Wm-2 leading to an average annual difference between ground and air temperatures, Δ Tg-a, of 2.55 K (±0.01) from 1993-2003. The temperature difference varies from -5 K to +10 K when averaged over a diurnal cycle, and from 2.50 K to 2.60 K over an annual cycle. However, inter-annual variations in insulation are less than 1 Wm-2; consequently, solar radiation is not observed to affect the inter-annual tracking at the site. 3) Model studies snow-ground thermal interactions at EPO demonstrate that seasonal snow cover can either warm or cool the ground relative to the annual mean air temperature and that the winter snow effect is an order of magnitude smaller than the summer radiation effect at the site. 4) Temperature observations at various depths within the granite and soils at the site allow us to make estimates of in-situ thermal diffusivity and its changes with time. The "apparent" thermal diffusivity of the upper meter of granite at EPO ranges from 0.88-0.98 x 10-6 m2s-1 while the soil varies from 0.57-0.68 x 10-6 m2s-1. The accumulation of data at EPO leads to a quantitative

  9. Air Cooling for High Temperature Power Electronics (Presentation)

    SciTech Connect

    Waye, S.; Musselman, M.; King, C.

    2014-09-01

    Current emphasis on developing high-temperature power electronics, including wide-bandgap materials such as silicon carbide and gallium nitride, increases the opportunity for a completely air-cooled inverter at higher powers. This removes the liquid cooling system for the inverter, saving weight and volume on the liquid-to-air heat exchanger, coolant lines, pumps, and coolant, replacing them with just a fan and air supply ducting. We investigate the potential for an air-cooled heat exchanger from a component and systems-level approach to meet specific power and power density targets. A proposed baseline air-cooled heat exchanger design that does not meet those targets was optimized using a parametric computational fluid dynamics analysis, examining the effects of heat exchanger geometry and device location, fixing the device heat dissipation and maximum junction temperature. The CFD results were extrapolated to a full inverter, including casing, capacitor, bus bar, gate driver, and control board component weights and volumes. Surrogate ducting was tested to understand the pressure drop and subsequent system parasitic load. Geometries that met targets with acceptable loads on the system were down-selected for experimentation. Nine baseline configuration modules dissipated the target heat dissipation, but fell below specific power and power density targets. Six optimized configuration modules dissipated the target heat load, exceeding the specific power and power density targets. By maintaining the same 175 degrees C maximum junction temperature, an optimized heat exchanger design and higher device heat fluxes allowed a reduction in the number of modules required, increasing specific power and power density while still maintaining the inverter power.

  10. Temperature Variations Recorded During Interinstitutional Air Shipments of Laboratory Mice

    PubMed Central

    Syversen, Eric; Pineda, Fernando J; Watson, Julie

    2008-01-01

    Despite extensive guidelines and regulations that govern most aspects of rodent shipping, few data are available on the physical environment experienced by rodents during shipment. To document the thermal environment experienced by mice during air shipments, we recorded temperatures at 1-min intervals throughout 103 routine interinstitutional shipments originating at our institution. We found that 49.5% of shipments were exposed to high temperatures (greater than 29.4 °C), 14.6% to low temperatures (less than 7.2 °C), and 61% to temperature variations of 11 °C or more. International shipments were more likely than domestic shipments to experience temperature extremes and large variations in temperature. Freight forwarders using passenger airlines rather than their own airplanes were more likely to have shipments that experienced temperature extremes or variations. Temperature variations were most common during stopovers. Some airlines were more likely than others to experience inflight temperature extremes or swings. Most domestic shipments lasted at least 24 h, whereas international shipments lasted 48 to 72 h. Despite exposure to high and low temperatures, animals in all but 1 shipment arrived alive. We suggest that simple measures, such as shipping at night during hot weather, provision of nesting material in shipping crates, and specifying aircraft cargo-hold temperatures that are suitable for rodents, could reduce temperature-induced stress. Measures such as additional training for airport ground crews, as previously recommended by the American Veterinary Medical Association, could further reduce exposure of rodents to extreme ambient temperatures during airport stopovers. PMID:18210996

  11. Zero-Temperature Fluctuations in Short-Range Spin Glasses

    NASA Astrophysics Data System (ADS)

    Arguin, L.-P.; Newman, C. M.; Stein, D. L.; Wehr, J.

    2016-06-01

    We consider the energy difference restricted to a finite volume for certain pairs of incongruent ground states (if they exist) in the d-dimensional Edwards-Anderson Ising spin glass at zero temperature. We prove that the variance of this quantity with respect to the couplings grows proportionally to the volume in any d ≥ 2. An essential aspect of our result is the use of the excitation metastate. As an illustration of potential applications, we use this result to restrict the possible structure of spin glass ground states in two dimensions.

  12. Global surface air temperature variations: 1851-1984

    SciTech Connect

    Jones, P.D.; Raper, S.C.B.; Kelly, P.M.

    1986-11-01

    Many attempts have been made to combine station surface air temperature data into an average for the Northern Hemisphere. Fewer attempts have been made for the Southern Hemisphere because of the unavailability of data from the Antarctic mainland before the 1950s and the uncertainty of making a hemispheric estimate based solely on land-based analyses for a hemisphere that is 80% ocean. Past estimates have been based largely on data from the World Weather Records (Smithsonian Institution, 1927, 1935, 1947, and U.S. Weather Bureau, 1959-82) and have been made without considerable effort to detect and correct station inhomogeneities. Better estimates for the Southern Hemisphere are now possible because of the availability of 30 years of climatological data from Antarctica. The mean monthly surface air temperature anomalies presented in this package for the than those previously published because of the incorporation of data previously hidden away in archives and the analysis of station homogeneity before estimation.

  13. Neutral air density and temperature measurements by the TOTAL instrument aboard the ROSE payloads

    NASA Astrophysics Data System (ADS)

    Friker, A.; Luebken, F.-J.

    1992-06-01

    Four ROSE payloads, launched from November 1988 to February 1989 from northern Scandinavia, carried ionization gauges ('TOTAL' instruments) for neutral air density measurements in the altitude range 90-105 km. Temperature profiles are derived by integrating the number density profiles. Density and temperature data are presented. The limitations of the measurement technique as well as instrumental errors are discussed. In one of the flights (F1) a significant temperature enhancement was observed at an altitude where plasma instabilities were detected by independent measurements.

  14. Antarctic Sea ice variations and seasonal air temperature relationships

    NASA Technical Reports Server (NTRS)

    Weatherly, John W.; Walsh, John E.; Zwally, H. J.

    1991-01-01

    Data through 1987 are used to determine the regional and seasonal dependencies of recent trends of Antarctic temperature and sea ice. Lead-lag relationships involving regional sea ice and air temperature are systematically evaluated, with an eye toward the ice-temperature feedbacks that may influence climatic change. Over the 1958-1087 period the temperature trends are positive in all seasons. For the 15 years (l973-l987) for which ice data are available, the trends are predominantly positive only in winter and summer, and are most strongly positive over the Antarctic Peninsula. The spatially aggregated trend of temperature for this latter period is small but positive, while the corresponding trend of ice coverage is small but negative. Lag correlations between seasonal anomalies of the two variables are generally stronger with ice lagging the summer temperatures and with ice leading the winter temperatures. The implication is that summer temperatures predispose the near-surface waters to above-or below-normal ice coverage in the following fall and winter.

  15. Development of a high-temperature air-blown gasification system.

    PubMed

    Pian, C C; Yoshikawa, K

    2001-09-01

    Current status of high-temperature air-blown gasification technology development is reviewed. This advanced gasification system utilizes preheated air to convert coal and waste-derived fuels into synthetic fuel gas and value-added byproducts. A series of demonstrated, independent technologies are combined to form the core of this gasification system. A high-temperature, rapid devolatilization process is used to enhance the volatile yields from the fuel and to improve the gasification efficiency. A high-temperature pebble bed filter is used to remove to the slag and particulates from the synthetic fuel gas. Finally, a novel regenerative heater is used to supply the high-temperature air for the gasifier. Component development tests have shown that higher gasification efficiencies can be obtained at more fuel-rich operating conditions when high-temperature air is used as the gasification agent. Test results also demonstrated the flex-fuel capabilities of the gasifier design. Potential uses of this technology range from large-scale integrated gasification power plants to small-scale waste-to-energy applications.

  16. Increasing EDV Range through Intelligent Cabin Air Handling Strategies: Annual Progress Report

    SciTech Connect

    Leighton, Daniel; Rugh, John

    2016-08-01

    Computational fluid dynamics (CFD) simulations of a Ford Focus Electric demonstrated that a split flow heating, ventilating and air conditioning (HVAC) system with rear recirculation ducts can reduce cabin heating loads by up to 57.4% relative to full fresh air usage under some conditions (steady state, four passengers, ambient temperature of -5 deg C). Simulations also showed that implementing a continuous recirculation fraction control system into the original equipment manufacturer (OEM) HVAC system can reduce cabin heating loads by up to 50.0% relative to full fresh air usage under some conditions (steady state, four passengers, ambient temperature of -5 deg C). Identified that continuous fractional recirculation control of the OEM system can provide significant energy savings for EVs at minimal additional cost, while a split flow HVAC system with rear recirculation ducts only provides minimal additional improvement at significant additional cost.

  17. Daily Air Temperature and Electricity Load in Spain.

    NASA Astrophysics Data System (ADS)

    Valor, Enric; Meneu, Vicente; Caselles, Vicente

    2001-08-01

    Weather has a significant impact on different sectors of the economy. One of the most sensitive is the electricity market, because power demand is linked to several weather variables, mainly the air temperature. This work analyzes the relationship between electricity load and daily air temperature in Spain, using a population-weighted temperature index. The electricity demand shows a significant trend due to socioeconomic factors, in addition to daily and monthly seasonal effects that have been taken into account to isolate the weather influence on electricity load. The results indicate that the relationship is nonlinear, showing a `comfort interval' of ±3°C around 18°C and two saturation points beyond which the electricity load no longer increases. The analysis has also revealed that the sensitivity of electricity load to daily air temperature has increased along time, in a higher degree for summer than for winter, although the sensitivity in the cold season is always more significant than in the warm season. Two different temperature-derived variables that allow a better characterization of the observed relationship have been used: the heating and cooling degree-days. The regression of electricity data on them defines the heating and cooling demand functions, which show correlation coefficients of 0.79 and 0.87, and predicts electricity load with standard errors of estimate of ±4% and ±2%, respectively. The maximum elasticity of electricity demand is observed at 7 cooling degree-days and 9 heating degree-days, and the saturation points are reached at 11 cooling degree-days and 13 heating degree-days, respectively. These results are helpful in modeling electricity load behavior for predictive purposes.

  18. Advances in Fast-response Acoustically Derived Air-temperature Measurements

    NASA Astrophysics Data System (ADS)

    Bogoev, I.; Jacobsen, L.; Horst, T. W.; Conrad, B.

    2015-12-01

    Fast-response accurate air-temperature measurements are required when estimating turbulent fluxes of heat, water and carbon dioxide by open-path eddy-covariance technique. In comparison with contact thermometers like thermocouples, ultra-sonic thermometers do not suffer from solar radiation loading, water vapor condensation and evaporative cooling effects. Consequently they have the potential to provide more accurate true air temperature measurements. The absolute accuracy of the ultrasonic thermometer is limited by the following parameters: the distance between the transducer pairs, transducer delays associated with the electrical-acoustic signal conversion that vary with temperature, components of the wind vector that are normal to the ultrasonic paths, and humidity.The distance between the transducer pairs is commonly obtained by coordinate measuring machine. Improved accuracy demonstrated in this study results from increased stiffness in the anemometer head to better maintain the ultrasonic path-length distances. To further improve accuracy and account for changes in transducer delays and distance as a function of temperature, these parameters are characterized in a zero-wind chamber over the entire operating temperature range. When the sonic anemometer is combined with a co-located fast-response water vapor analyzer, like in the IRGASON instrument, speed of sound can be compensated for humidity effects on a point-by-point basis resulting in a true fast-response air temperature measurement. Laboratory test results show that when the above steps are implemented in the calibration of the ultrasonic thermometer air-temperature accuracy better than ±0.5 degrees Celsius can be achieved over the entire operating range. The approach is also validated in a field inter-comparison with an aspirated thermistor probe mounted in a radiation shield.

  19. Validation of zero-order feedback strategies for medium range air-to-air interception in a horizontal plane

    NASA Technical Reports Server (NTRS)

    Shinar, J.

    1982-01-01

    A zero order feedback solution of a variable speed interception game between two aircraft in the horizontal plane, obtained by using the method of forced singular perturbation (FSP), is compared with the exact open loop solution. The comparison indicates that for initial distances of separation larger than eight turning radii of the evader, the accuracy of the feedback approximation is better than one percent. The result validates the zero order FSP approximation for medium range air combat analysis.

  20. An Experimental Investigation Into the Temperature Profile of a Compliant Foil Air Bearing

    NASA Technical Reports Server (NTRS)

    Radil, Kevin; Zeszotek, Michelle

    2004-01-01

    A series of tests was performed to determine the internal temperature profile in a compliant bump-type foil journal air bearing operating at room temperature under various speeds and load conditions. The temperature profile was collected by instrumenting a foil bearing with nine, type K thermocouples arranged in the center and along the bearing s edges in order to measure local temperatures and estimate thermal gradients in the axial and circumferential directions. To facilitate the measurement of maximum temperatures from viscous shearing in the air film, the thermocouples were tack welded to the backside of the bumps that were in direct contact with the top foil. The mating journal was coated with a high temperature solid lubricant that, together with the bearing, underwent high temperature start-stop cycles to produce a smooth, steady-state run-in surface. Tests were conducted at speeds from 20 to 50 krpm and loads ranging from 9 to 222 N. The results indicate that, over the conditions tested, both journal rotational speed and radial load are responsible for heat generation with speed playing a more significant role in the magnitude of the temperatures. The temperature distribution was nearly symmetric about the bearing center at 20 and 30 krpm but became slightly skewed toward one side at 40 and 50 krpm. Surprisingly, the maximum temperatures did not occur at the bearing edge where the minimum film thickness is expected but rather in the middle of the bearing where analytical investigations have predicted the air film to be much thicker. Thermal gradients were common during testing and were strongest in the axial direction from the middle of the bearing to its edges, reaching 3.78 8C/mm. The temperature profile indicated the circumferential thermal gradients were negligible.

  1. Air-sea interactions in sea surface temperature frontal region

    NASA Astrophysics Data System (ADS)

    Pianezze, Joris; Redelsperger, Jean-Luc; Ardhuin, Fabrice; Reynaud, Thierry; Marié, Louis; Bouin, Marie-Noelle; Garnier, Valerie

    2015-04-01

    Representation of air-sea exchanges in coastal, regional and global models represent a challenge firstly due to the small scale of acting turbulent processes comparatively to the resolved scales of these models. Beyond this subgrid parameterization issue, a comprehensive understanding of air-sea interactions at the turbulent process scales is still lacking. Many successful efforts are dedicated to measure the energy and mass exchanges between atmosphere and ocean, including the effect of surface waves. In comparison less efforts are brought to understand the interactions between the atmospheric boundary layer and the oceanic mixing layer. In this regard, we are developing research mainly based on ideal and realistic numerical simulations which resolve very small scales (horizontal resolutions from 1 to 100 meters) in using grid nesting technics and coupled ocean-wave-atmosphere models. As a first step, the impact of marked gradients in sea surface temperatures (SST) on air-sea exchanges has been explored through realistic numerical simulations at 100m horizontal resolution. Results from simulations of a case observed during the FROMVAR experiment will be shown. The talk will mainly focus on the marked impact of SST front on the atmospheric boundary layer (stability and winds), the air-sea exchanges and surface parameters (rugosity, drag coefficient) Results will be also shown on the strong impact on the simulated atmosphere of small scale variability of SST field.

  2. Unique, clean-air, continuous-flow, high-stagnation-temperature facility for supersonic combustion research

    NASA Technical Reports Server (NTRS)

    Krauss, R. H.; Mcdaniel, J. C., Jr.; Scott, J. E., Jr.; Whitehurst, R. B., III; Segal, C.

    1988-01-01

    Accurate, spatially-resolved measurements can be conducted of a model supersonic combustor in a clean air/continuous flow supersonic combustion facility whose long run times will allow not only the point-by-point mapping of flow field variables with laser diagnostics but facilitate the simulation of steady-state combustor conditions. The facility will provide a Mach 2 freestream with static pressures in the 1 to 1/6 atm range, and stagnation temperatures of up to 2000 K.

  3. Optical refractive index of air: dependence on pressure, temperature and composition.

    PubMed

    Owens, J C

    1967-01-01

    The theoretical background and present status of formulas for the refractive index of air are reviewed. In supplement to Edlén's recently revised formula for relative refractivity, the density dependence of refractive index is reanalyzed. New formulas are presented for both phase and group refractive index which are more useful over a wide range of pressure, temperature, and composition than any presently available. The application of the new formulas to optical distance measuring is briefly discussed.

  4. 33 CFR 334.640 - Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Bay, Fla.; Air Force rocket firing range. 334.640 Section 334.640 Navigation and Navigable Waters... REGULATIONS § 334.640 Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range. (a) The... enforced by the Commander, Moody Air Force Base, Valdosta, Georgia, and such agencies as he may designate....

  5. 33 CFR 334.640 - Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Bay, Fla.; Air Force rocket firing range. 334.640 Section 334.640 Navigation and Navigable Waters... REGULATIONS § 334.640 Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range. (a) The... enforced by the Commander, Moody Air Force Base, Valdosta, Georgia, and such agencies as he may designate....

  6. 33 CFR 334.640 - Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Bay, Fla.; Air Force rocket firing range. 334.640 Section 334.640 Navigation and Navigable Waters... REGULATIONS § 334.640 Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range. (a) The... enforced by the Commander, Moody Air Force Base, Valdosta, Georgia, and such agencies as he may designate....

  7. 33 CFR 334.640 - Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Bay, Fla.; Air Force rocket firing range. 334.640 Section 334.640 Navigation and Navigable Waters... REGULATIONS § 334.640 Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range. (a) The... enforced by the Commander, Moody Air Force Base, Valdosta, Georgia, and such agencies as he may designate....

  8. 33 CFR 334.640 - Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Bay, Fla.; Air Force rocket firing range. 334.640 Section 334.640 Navigation and Navigable Waters... REGULATIONS § 334.640 Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range. (a) The... enforced by the Commander, Moody Air Force Base, Valdosta, Georgia, and such agencies as he may designate....

  9. Application of 3-D Urbanization Index to Assess Impact of Urbanization on Air Temperature

    PubMed Central

    Wu, Chih-Da; Lung, Shih-Chun Candice

    2016-01-01

    The lack of appropriate methodologies and indicators to quantify three-dimensional (3-D) building constructions poses challenges to authorities and urban planners when formulating polices to reduce health risks due to heat stress. This study evaluated the applicability of an innovative three-dimensional Urbanization Index (3DUI), based on remote sensing database, with a 5 m spatial resolution of 3-D man-made constructions to representing intra-urban variability of air temperature by assessing correlation of 3DUI with air temperature from a 3-D perspective. The results showed robust high correlation coefficients, ranging from 0.83 to 0.85, obtained within the 1,000 m circular buffer around weather stations regardless of season, year, or spatial location. Our findings demonstrated not only the strength of 3DUI in representing intra-urban air-temperature variability, but also its great potential for heat stress assessment within cities. In view of the maximum correlation between building volumes within the 1,000 m circular buffer and ambient air temperature, urban planning should consider setting ceilings for man-made construction volume in each 2 × 2 km2 residential community for thermal environment regulation, especially in Asian metropolis with high population density in city centers. PMID:27079537

  10. Application of 3-D Urbanization Index to Assess Impact of Urbanization on Air Temperature

    NASA Astrophysics Data System (ADS)

    Wu, Chih-Da; Lung, Shih-Chun Candice

    2016-04-01

    The lack of appropriate methodologies and indicators to quantify three-dimensional (3-D) building constructions poses challenges to authorities and urban planners when formulating polices to reduce health risks due to heat stress. This study evaluated the applicability of an innovative three-dimensional Urbanization Index (3DUI), based on remote sensing database, with a 5 m spatial resolution of 3-D man-made constructions to representing intra-urban variability of air temperature by assessing correlation of 3DUI with air temperature from a 3-D perspective. The results showed robust high correlation coefficients, ranging from 0.83 to 0.85, obtained within the 1,000 m circular buffer around weather stations regardless of season, year, or spatial location. Our findings demonstrated not only the strength of 3DUI in representing intra-urban air-temperature variability, but also its great potential for heat stress assessment within cities. In view of the maximum correlation between building volumes within the 1,000 m circular buffer and ambient air temperature, urban planning should consider setting ceilings for man-made construction volume in each 2 × 2 km2 residential community for thermal environment regulation, especially in Asian metropolis with high population density in city centers.

  11. Spatial distribution of air temperature in Toruń (Central Poland) and its causes

    NASA Astrophysics Data System (ADS)

    Przybylak, Rajmund; Uscka-Kowalkowska, Joanna; Araźny, Andrzej; Kejna, Marek; Kunz, Mieczysław; Maszewski, Rafał

    2017-01-01

    In this article, the results of an investigation into the air temperature pattern and development (including the urban heat island (UHI)) in Toruń (central Poland) are presented. For the analysis, daily mean temperature (Ti) as well as daily maximum (Tmax) and minimum (Tmin) temperatures for 2012 gathered for 20 sites, evenly distributed in the area of city, have been taken as source data. Additionally, in order to provide more extensive characteristics of the diversity of the air temperature in the study area, the diurnal temperature range (DTR) and the number of the so-called characteristic days were calculated as well. The impact of weather conditions (cloudiness and wind speed), atmospheric circulation, urban morphological parameters and land cover on the UHI in the study area was investigated. In Toruń, according to the present study, the average UHI intensity in 2012 was equal to 1.0 °C. The rise of cloudiness and wind speed led to a decrease of the magnitude of the UHI. Generally, in most cases, anticyclonic situations favour increased thermal contrast between rural and city areas, particularly in summer. Warm western circulation types significantly reduced temperature differences in the western side of the city and enlarged them in the eastern side of the city. Eastern cold types also have a similar influence on air temperature differences. Positive and statistically significant correlations have been found between the percentage of built-up areas (sealing factor) and air temperature. Conversely, sky view factor (SVF) reveals negative correlations which are statistically significant only for Tmin.

  12. Generation of low-temperature air plasma for food processing

    NASA Astrophysics Data System (ADS)

    Stepanova, Olga; Demidova, Maria; Astafiev, Alexander; Pinchuk, Mikhail; Balkir, Pinar; Turantas, Fulya

    2015-11-01

    The project is aimed at developing a physical and technical foundation of generating plasma with low gas temperature at atmospheric pressure for food industry needs. As known, plasma has an antimicrobial effect on the numerous types of microorganisms, including those that cause food spoilage. In this work an original experimental setup has been developed for the treatment of different foods. It is based on initiating corona or dielectric-barrier discharge in a chamber filled with ambient air in combination with a certain helium admixture. The experimental setup provides various conditions of discharge generation (including discharge gap geometry, supply voltage, velocity of gas flow, content of helium admixture in air and working pressure) and allows for the measurement of the electrical discharge parameters. Some recommendations on choosing optimal conditions of discharge generation for experiments on plasma food processing are developed.

  13. Variable air temperature response of gas-phase atmospheric polychlorinated biphenyls near a former manufacturing facility.

    PubMed

    Hermanson, Mark H; Scholten, Cheryl A; Compher, Kevin

    2003-09-15

    Many investigations of gas-phase atmospheric PCB show a strong relationship between concentration and air temperature, especially near PCB sources. Comparative gas-phase atmospheric PCB trends during an annual temperature regime at two sites near a former PCB manufacturing plant and nearby PCB landfills in Anniston, AL, indicate a departure from this trend. The Mars Hill sampling site, located closest to the plant and landfills, shows an annual average sigmaPCB concentration of 27 ng m(-3) (ranging from 8.7 to 82 ng m(-3)) three times the average at Carter, 1.5 km away (9 ng m(-3), ranging from 1.1 to 39). However, total PCB and congener concentrations vary more with air temperature at Carter where PCB are evaporating from surfaces during warmer weather. The slopes of the Clausius-Clapeyron plots of 18 of the most concentrated congeners representing dichloro- through heptachlorobiphenyl homologues are significantly higher at the Carter site. While some of the atmospheric PCB at Mars Hill is derived from ground surface evaporation, the source of much of it apparently is the material buried in the landfills, which has different thermal properties than surface materials and is not in equilibrium with air temperature.

  14. 14 CFR 25.1527 - Ambient air temperature and operating altitude.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Ambient air temperature and operating... Information Operating Limitations § 25.1527 Ambient air temperature and operating altitude. The extremes of the ambient air temperature and operating altitude for which operation is allowed, as limited...

  15. 14 CFR 25.1527 - Ambient air temperature and operating altitude.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Ambient air temperature and operating... Information Operating Limitations § 25.1527 Ambient air temperature and operating altitude. The extremes of the ambient air temperature and operating altitude for which operation is allowed, as limited...

  16. 14 CFR 25.1527 - Ambient air temperature and operating altitude.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Ambient air temperature and operating... Information Operating Limitations § 25.1527 Ambient air temperature and operating altitude. The extremes of the ambient air temperature and operating altitude for which operation is allowed, as limited...

  17. 14 CFR 25.1527 - Ambient air temperature and operating altitude.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ambient air temperature and operating... Information Operating Limitations § 25.1527 Ambient air temperature and operating altitude. The extremes of the ambient air temperature and operating altitude for which operation is allowed, as limited...

  18. 14 CFR 25.1527 - Ambient air temperature and operating altitude.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ambient air temperature and operating... Information Operating Limitations § 25.1527 Ambient air temperature and operating altitude. The extremes of the ambient air temperature and operating altitude for which operation is allowed, as limited...

  19. The impact of humidity on evaporative cooling in small desert birds exposed to high air temperatures.

    PubMed

    Gerson, Alexander R; Smith, Eric Krabbe; Smit, Ben; McKechnie, Andrew E; Wolf, Blair O

    2014-01-01

    Environmental temperatures that exceed body temperature (Tb) force endothermic animals to rely solely on evaporative cooling to dissipate heat. However, evaporative heat dissipation can be drastically reduced by environmental humidity, imposing a thermoregulatory challenge. The goal of this study was to investigate the effects of humidity on the thermoregulation of desert birds and to compare the sensitivity of cutaneous and respiratory evaporation to reduced vapor density gradients. Rates of evaporative water loss, metabolic rate, and Tb were measured in birds exposed to humidities ranging from ∼2 to 30 g H2O m(-3) (0%-100% relative humidity at 30°C) at air temperatures between 44° and 56°C. In sociable weavers, a species that dissipates heat primarily through panting, rates of evaporative water loss were inhibited by as much as 36% by high humidity at 48°C, and these birds showed a high degree of hyperthermia. At lower temperatures (40°-44°C), evaporative water loss was largely unaffected by humidity in this species. In Namaqua doves, which primarily use cutaneous evaporation, increasing humidity reduced rates of evaporative water loss, but overall rates of water loss were lower than those observed in sociable weavers. Our data suggest that cutaneous evaporation is more efficient than panting, requiring less water to maintain Tb at a given temperature, but panting appears less sensitive to humidity over the air temperature range investigated here.

  20. Low-cycle fatigue of two austenitic alloys in hydrogen gas and air at elevated temperatures

    NASA Technical Reports Server (NTRS)

    Jaske, C. E.; Rice, R. C.

    1976-01-01

    The low-cycle fatigue resistance of type 347 stainless steel and Hastelloy Alloy X was evaluated in constant-amplitude, strain-controlled fatigue tests conducted under continuous negative strain cycling at a constant strain rate of 0.001 per sec and at total axial strain ranges of 1.5, 3.0, and 5.0 percent in both hydrogen gas and laboratory air environments in the temperature range 538-871 C. Elevated-temperature, compressive-strain hold-time experiments were also conducted. In hydrogen, the cyclic stress-strain behavior of both materials at 538 C was characterized by appreciable cyclic hardening at all strain ranges. At 871 C neither material hardened significantly; in fact, at 5% strain range 347 steel showed continuous cyclic softening until failure. The fatigue resistance of 347 steel was slightly higher than that of Alloy X at all temperatures and strain ranges. Ten-minute compressive hold time experiments at 760 and 871 C resulted in increased fatigue lives for 347 steel and decreased fatigue lives for Alloy X. Both alloys showed slightly lower fatigue resistance in air than in hydrogen. Some fractographic and metallographic results are also given.

  1. Global climate change: impact of diurnal temperature range on mortality in Guangzhou, China.

    PubMed

    Yang, Jun; Liu, Hua-Zhang; Ou, Chun-Quan; Lin, Guo-Zhen; Zhou, Qin; Shen, Gi-Chuan; Chen, Ping-Yan; Guo, Yuming

    2013-04-01

    Diurnal temperature range (DTR) is an important meteorological indicator associated with global climate change, but little is known about the effects of DTR on mortality. We examined the effects of DTR on cause-/age-/education-specific mortality in Guangzhou, a subtropical city in China during 2003-2010. A quasi-Poisson regression model combined with distributed lag non-linear model was used to examine the effects of DTR, after controlling for daily mean temperature, air pollutants, season and day of the week. A 1 °C increase in DTR at lag 0-4 days was associated with a 0.47% (95% confidence interval: 0.01%-0.93%) increase in non-accidental mortality. Stroke mortality was most sensitive to DTR. Female, the elderly and those with low education were more susceptible to DTR than male, the youth and those with high education, respectively. Our findings suggest that vulnerable subpopulations should pay more attention to protect themselves from unstable daily weather.

  2. Cascaded optical isolator configuration having high-isolation characteristics over a wide temperature and wavelength range.

    PubMed

    Shiraishi, K; Kawakami, S

    1987-07-01

    A new configuration of a cascaded optical isolator with high isolation over a wide range of temperature and wavelength is proposed. The configuration consists of two unit isolators, each of which is optimized for a different temperature and wavelength.

  3. Model-based estimation of changes in air temperature seasonality

    NASA Astrophysics Data System (ADS)

    Barbosa, Susana; Trigo, Ricardo

    2010-05-01

    Seasonality is a ubiquitous feature in climate time series. Climate change is expected to involve not only changes in the mean of climate parameters but also changes in the characteristics of the corresponding seasonal cycle. Therefore the identification and quantification of changes in seasonality is a highly relevant topic in climate analysis, particularly in a global warming context. However, the analysis of seasonality is far from a trivial task. A key challenge is the discrimination between long-term changes in the mean and long-term changes in the seasonal pattern itself, which requires the use of appropriate statistical approaches in order to be able to distinguish between overall trends in the mean and trends in the seasons. Model based approaches are particularly suitable for the analysis of seasonality, enabling to assess uncertainties in the amplitude and phase of seasonal patterns within a well defined statistical framework. This work addresses the changes in the seasonality of air temperature over the 20th century. The analysed data are global air temperature values close to surface (2m above ground) and mid-troposphere (500 hPa geopotential height) from the recently developed 20th century reanalysis. This new 3-D Reanalysis dataset is available since 1891, considerably extending all other Reanalyses currently in use (e.g. NCAR, ECWMF), and was obtained with the Ensemble Filter (Compo et al., 2006) by assimilation of pressure observations into a state-of-the-art atmospheric general circulation model that includes the radiative effects of historical time-varying CO2 concentrations, volcanic aerosol emissions and solar output variations. A modeling approach based on autoregression (Barbosa et al, 2008; Barbosa, 2009) is applied within a Bayesian framework for the estimation of a time varying seasonal pattern and further quantification of changes in the amplitude and phase of air temperature over the 20th century. Barbosa, SM, Silva, ME, Fernandes, MJ

  4. Heart rate, multiple body temperature, long-range and long-life telemetry system for free-ranging animals

    NASA Technical Reports Server (NTRS)

    Lund, G. F.; Westbrook, R. M.; Fryer, T. B.

    1980-01-01

    The design details and rationale for a versatile, long-range, long-life telemetry data acquisition system for heart rates and body temperatures at multiple locations from free-ranging animals are presented. The design comprises an implantable transmitter for short to medium range transmission, a receiver retransmitter collar to be worn for long-range transmission, and a signal conditioner interface circuit to assist in signal discrimination and demodulation of receiver or tape-recorded audio outputs. Implanted electrodes are used to obtain an ECG, from which R-wave characteristics are selected to trigger a short RF pulse. Pulses carrying heart rate information are interrupted periodically by a series of pulse interval modulated RF pulses conveying temperature information sensed at desired locations by thermistors. Pulse duration and pulse sequencing are used to discriminate between heart rate and temperature pulses as well as radio frequency interference. The implanted transmitter may be used alone for medium and short-range tracking, or with a receiver-transmitter collar that employs commercial tracking equipment for transmissions of up to 12 km. A system prototype has been tested on a dog.

  5. Emissions of an AVCO Lycoming 0-320-DIAD air cooled light aircraft engine as a function of fuel-air ratio, timing, and air temperature and humidity

    NASA Technical Reports Server (NTRS)

    Meng, P. R.; Skorobatckyi, M.; Cosgrove, D. V.; Kempke, E. E., Jr.

    1976-01-01

    A carbureted aircraft engine was operated over a range of test conditions to establish the exhaust levels over the EPA seven-mode emissions cycle. Baseline (full rich production limit) exhaust emissions at an induction air temperature of 59 F and near zero relative humidity were 90 percent of the EPA standard for HC, 35 percent for NOx, and 161 percent for CO. Changes in ignition timing around the standard 25 deg BTDC from 30 deg BTDC to 20 deg BTDC had little effect on the exhaust emissions. Retarding the timing to 15 deg BTDC increased both the HC and CO emissions and decreased NOx emissions. HC and CO emissions decreased as the carburetor was leaned out, while NOx emissions increased. The EPA emission standards were marginally achieved at two leanout conditions. Variations in the quantity of cooling air flow over the engine had no effect on exhaust emissions. Temperature-humidity effects at the higher values of air temperature and relative humidity tested indicated that the HC and CO emissions increased significantly, while the NOx emissions decreased.

  6. Effect of Ambient Design Temperature on Air-Cooled Binary Plant Output

    SciTech Connect

    Dan Wendt; Greg Mines

    2011-10-01

    Air-cooled binary plants are designed to provide a specified level of power production at a particular air temperature. Nominally this air temperature is the annual mean or average air temperature for the plant location. This study investigates the effect that changing the design air temperature has on power generation for an air-cooled binary plant producing power from a resource with a declining production fluid temperature and fluctuating ambient temperatures. This analysis was performed for plants operating both with and without a geothermal fluid outlet temperature limit. Aspen Plus process simulation software was used to develop optimal air-cooled binary plant designs for specific ambient temperatures as well as to rate the performance of the plant designs at off-design operating conditions. Results include calculation of annual and plant lifetime power generation as well as evaluation of plant operating characteristics, such as improved power generation capabilities during summer months when electric power prices are at peak levels.

  7. High-temperature hydrogen-air-steam detonation experiments in the BNL small-scale development apparatus

    SciTech Connect

    Ciccarelli, G.; Ginsburg, T.; Boccio, J.; Economos, C.; Finfrock, C.; Gerlach, L.; Sato, K.; Kinoshita, M.

    1994-08-01

    The Small-Scale Development Apparatus (SSDA) was constructed to provide a preliminary set of experimental data to characterize the effect of temperature on the ability of hydrogen-air-steam mixtures to undergo detonations and, equally important, to support design of the larger scale High-Temperature Combustion Facility (HTCF) by providing a test bed for solution of a number of high-temperature design and operational problems. The SSDA, the central element of which is a 10-cm inside diameter, 6.1-m long tubular test vessel designed to permit detonation experiments at temperatures up to 700K, was employed to study self-sustained detonations in gaseous mixtures of hydrogen, air, and steam at temperatures between 300K and 650K at a fixed initial pressure of 0.1 MPa. Hydrogen-air mixtures with hydrogen composition from 9 to 60 percent by volume and steam fractions up to 35 percent by volume were studied for stoichiometric hydrogen-air-steam mixtures. Detonation cell size measurements provide clear evidence that the effect of hydrogen-air gas mixture temperature, in the range 300K-650K, is to decrease cell size and, hence, to increase the sensitivity of the mixture to undergo detonations. The effect of steam content, at any given temperature, is to increase the cell size and, thereby, to decrease the sensitivity of stoichiometric hydrogen-air mixtures. The hydrogen-air detonability limits for the 10-cm inside diameter SSDA test vessel, based upon the onset of single-head spin, decreased from 15 percent hydrogen at 300K down to between 9 and 10 percent hydrogen at 650K. The one-dimensional ZND model does a very good job at predicting the overall trends in the cell size data over the range of hydrogen-air-steam mixture compositions and temperature studied in the experiments.

  8. DDT in fuel air mixtures at elevated temperatures and pressures

    NASA Astrophysics Data System (ADS)

    Card, J.; Rival, D.; Ciccarelli, G.

    2005-11-01

    An experimental study was carried out to investigate flame acceleration and deflagration-to-detonation transition (DDT) in fuel air mixtures at initial temperatures up to 573 K and pressures up to 2 atm. The fuels investigated include hydrogen, ethylene, acetylene and JP-10 aviation fuel. The experiments were performed in a 3.1-m long, 10-cm inner-diameter heated detonation tube equipped with equally spaced orifice plates. Ionization probes were used to measure the flame time-of-arrival from which the average flame velocity versus propagation distance could be obtained. The DDT composition limits and the distance required for the flame to transition to detonation were obtained from this flame velocity data. The correlation developed by Veser et al. (run-up distance to supersonic flames in obstacle-laden tubes. In the proceedings of the 4th International Symposium on Hazards, Prevention and Mitigation of Industrial Explosions, France (2002)) for the flame choking distance proved to work very well for correlating the detonation run-up distance measured in the present study. The only exception was for the hydrogen air data at elevated initial temperatures which tended to fall outside the scatter of the hydrocarbon mixture data. The DDT limits obtained at room temperature were found to follow the classical d/λ = 1 correlation, where d is the orifice plate diameter and λ is the detonation cell size. Deviations found for the high-temperature data could be attributed to the one-dimensional ZND detonation structure model used to predict the detonation cell size for the DDT limit mixtures. This simple model was used in place of actual experimental data not currently available.

  9. Cloud-induced uncertainties in AIRS and ECMWF temperature and specific humidity

    NASA Astrophysics Data System (ADS)

    Wong, Sun; Fetzer, Eric J.; Schreier, Mathias; Manipon, Gerald; Fishbein, Evan F.; Kahn, Brian H.; Yue, Qing; Irion, Fredrick W.

    2015-03-01

    The uncertainties of the Atmospheric Infrared Sounder (AIRS) Level 2 version 6 specific humidity (q) and temperature (T) retrievals are quantified as functions of cloud types by comparison against Integrated Global Radiosonde Archive radiosonde measurements. The cloud types contained in an AIRS/Advanced Microwave Sounding Unit footprint are identified by collocated Moderate Resolution Imaging Spectroradiometer retrieved cloud optical depth (COD) and cloud top pressure. We also report results of similar validation of q and T from European Centre for Medium-Range Weather Forecasts (ECMWF) forecasts (EC) and retrievals from the AIRS Neural Network (NNW), which are used as the initial state for AIRS V6 physical retrievals. Differences caused by the variation in the measurement locations and times are estimated using EC, and all the comparisons of data sets against radiosonde measurements are corrected by these estimated differences. We report in detail the validation results for AIRS GOOD quality control, which is used for the AIRS Level 3 climate products. AIRS GOOD quality q reduces the dry biases inherited from the NNW in the middle troposphere under thin clouds but enhances dry biases in thick clouds throughout the troposphere (reaching -30% at 850 hPa near deep convective clouds), likely because the information contained in AIRS retrievals is obtained in cloud-cleared areas or above clouds within the field of regard. EC has small moist biases (~5-10%), which are within the uncertainty of radiosonde measurements, in thin and high clouds. Temperature biases of all data are within ±1 K at altitudes above the 700 hPa level but increase with decreasing altitude. Cloud-cleared retrievals lead to large AIRS cold biases (reaching about -2 K) in the lower troposphere for large COD, enhancing the cold biases inherited from the NNW. Consequently, AIRS GOOD quality T root-mean-squared errors (RMSEs) are slightly smaller than the NNW errors in thin clouds (1.5-2.5 K) but

  10. Medium-Range Air Quality Forecast During the Beijing Olympic Games

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Smith, J.; Wang, Z.; Luo, L.; Wu, Q.

    2008-12-01

    Prior to the XXIX Olympiad in Beijing, air quality was a major concern for many athletes and visitors to the Games. In response to the need for enhanced air quality forecasts, we explored and tested the capability of medium-range air quality forecasting in a multimodel ensemble system. The system consists of the Weather Research and Forecasting Model with Chemistry module (WRF-Chem), the Fifth-Generation NCAR/PennState Mesoscale Model (MM5), and the Nested Air Quality Prediction Modeling System (NAQPMS) developed at the Institute of Atmospheric Physics (IAP). Both MM5 and NAQPMS have been in operational use to produce short-term air quality forecasts. WRFChem is the major addition to the multimodel system. Forced with the forecast from the NCEP Global Ensemble Forecast System (GENS) at the lateral boundary, the multimodel system makes ensemble air quality forecasts out to 16 days with emission scenarios that reflect measures for the Olympics, including the closing down of factories around the city and beyond, a traffic control program that reduced the number of automobiles around the city by about half and elimination of all construction activities. Analyses of two forecasts are presented in this study. They were made on 5 August 2008 and 8 August 2008, both covering the entire Olympic period. Each forecast consists of three ensemble members that were produced with the same regional model but were forced by the control and two 'extremes' of the GENS forecast. The two extreme members were hand-picked to represent the best and worst case scenarios. The forecasts are evaluated with observations taken during the Olympic Games that include satellite observations, in-situ meteorological stations, LIDAR and air quality observations at the IAP tower site, 1 km away from the 'Bird Nest'. The analyses show good model skill in the first 3 days and generally satisfactory after 96 hours, with a successful forecast of potential pollution episode on 20 August 2008. The challenge

  11. Impact of Atlantic sea surface temperatures on the warmest global surface air temperature of 1998

    NASA Astrophysics Data System (ADS)

    Lu, Riyu

    2005-03-01

    The year 1998 is the warmest year in the record of instrumental measurements. In this study, an atmospheric general circulation model is used to investigate the role of sea surface temperatures (SSTs) in this warmth, with a focus on the role of the Atlantic Ocean. The model forced with the observed global SSTs captures the main features of land surface air temperature anomalies in 1998. A sensitivity experiment shows that in comparison with the global SST anomalies, the Atlantic SST anomalies can explain 35% of the global mean surface air temperature (GMAT) anomaly, and 57% of the land surface air temperature anomaly in 1998. The mechanisms through which the Atlantic Ocean influences the GMAT are likely different from season to season. Possible detailed mechanisms involve the impact of SST anomalies on local convection in the tropical Atlantic region, the consequent excitation of a Rossby wave response that propagates into the North Atlantic and the Eurasian continent in winter and spring, and the consequent changes in tropical Walker circulation in summer and autumn that induce changes in convection over the tropical Pacific. This in turn affects climate in Asia and Australia. The important role of the Atlantic Ocean suggests that attention should be paid not only to the tropical Pacific Ocean, but also to the tropical Atlantic Ocean in understanding the GMAT variability and its predictability.

  12. Meristem temperature substantially deviates from air temperature even in moderate environments: is the magnitude of this deviation species-specific?

    PubMed

    Savvides, Andreas; van Ieperen, Wim; Dieleman, Janneke A; Marcelis, Leo F M

    2013-11-01

    Meristem temperature (Tmeristem ) drives plant development but is hardly ever quantified. Instead, air temperature (Tair ) is usually used as its approximation. Meristems are enclosed within apical buds. Bud structure and function may differ across species. Therefore, Tmeristem may deviate from Tair in a species-specific way. Environmental variables (air temperature, vapour pressure deficit, radiation, and wind speed) were systematically varied to quantify the response of Tmeristem . This response was related to observations of bud structure and transpiration. Tomato and cucumber plants were used as model plants as they are morphologically distinct and usually growing in similar environments. Tmeristem substantially deviated from Tair in a species-specific manner under moderate environments. This deviation ranged between -2.6 and 3.8 °C in tomato and between -4.1 and 3.0 °C in cucumber. The lower Tmeristem observed in cucumber was linked with the higher transpiration of the bud foliage sheltering the meristem when compared with tomato plants. We here indicate that for properly linking growth and development of plants to temperature in future applications, for instance in climate change scenarios studies, Tmeristem should be used instead of Tair , as a species-specific trait highly reliant on various environmental factors.

  13. Case-Based Behavior Recognition in Beyond Visual Range Air Combat

    DTIC Science & Technology

    2015-05-01

    Case-Based Behavior Recognition in Beyond Visual Range Air Combat Hayley Borck 1 , Justin Karneeb 1 , Ron Alford 2 & David W. Aha 3 1Knexus...understanding the behaviors of hostile agents, which is challenging in partially observable environments such as the one we study. In particular, unobserved...hostile behaviors in our domain may alter the world state. To effectively counter hostile behaviors , they need to be recognized and predicted. We

  14. Daily Cycle of Air Temperature and Surface Temperature in Stone Forest

    NASA Astrophysics Data System (ADS)

    Wang, K.; Li, Y.; Wang, X.; Yuan, M.

    2013-12-01

    Urbanization is one of the most profound human activities that impact on climate change. In cities, where are highly artificial areas, the conflict between human activity and natural climate is particularly prominent. Urban areas always have the larger area of impervious land, the higher consumption of greenhouse gases, more emissions of anthropogenic heat and air pollution, all contribute to the urban warming phenomena. Understanding the mechanisms causing a variety of phenomena involved in the urban warming is critical to distinguish the anthropogenic effect and natural variation in the climate change. However, the exact dynamics of urban warming were poorly understood, and effective control strategies are not available. Here we present a study of the daily cycle of air temperature and surface temperature in Stone Forest. The specific heat of the stones in the Stone Forest and concrete of the man-made structures within the cities are approximate. Besides, the height of the Stone Forest and the height of buildings within the city are also similar. As a scenic area, the Stone Forest is being preserved and only opened for sightseeing. There is no anthropogenic heat, as well air pollution within the Stone Forest. The thermal environment in Stone Forest can be considered to be a simulation of thermal environment in the city, which can reveal the effect of man-made structures on urban thermal environment. We conducted the field studies and numerical analysis in the Stone Forest for 4 typical urban morphology and environment scenarios, including high-rise compact cities, low-rise sparse cities, garden cities and isolated single stone. Air temperature and relative humidity were measured every half an hour in 15 different locations, which within different spatial distribution of stones and can represent the four urban scenarios respectively. At the same time, an infrared camera was used to take thermal images and get the hourly surface temperatures of stones and

  15. Temperature profile and producer gas composition of high temperature air gasification of oil palm fronds

    NASA Astrophysics Data System (ADS)

    Guangul, F. M.; Sulaiman, S. A.; Ramli, A.

    2013-06-01

    Environmental pollution and scarcity of reliable energy source are the current pressing global problems which need a sustainable solution. Conversion of biomass to a producer gas through gasification process is one option to alleviate the aforementioned problems. In the current research the temperature profile and composition of the producer gas obtained from the gasification of oil palm fronds by using high temperature air were investigated and compared with unheated air. By preheating the gasifying air at 500°C the process temperature were improved and as a result the concentration of combustible gases and performance of the process were improved. The volumetric percentage of CO, CH4 and H2 were improved from 22.49, 1.98, and 9.67% to 24.98, to 2.48% and 13.58%, respectively. In addition, HHV, carbon conversion efficiency and cold gas efficiency were improver from 4.88 MJ/Nm3, 83.8% and 56.1% to 5.90 MJ/Nm3, 87.3% and 62.4%, respectively.

  16. Cyclic Oxidation of High-Temperature Alloy Wires in Air

    NASA Technical Reports Server (NTRS)

    Reigel, Marissa M.

    2004-01-01

    High-temperature alloy wires are proposed for use in seal applications for future re-useable space vehicles. These alloys offer the potential for improved wear resistance of the seals. The wires must withstand the high temperature environments the seals are subjected to as well as maintain their oxidation resistance during the heating and cooling cycles of vehicle re-entry. To model this, the wires were subjected to cyclic oxidation in stagnant air. of this layer formation is dependent on temperature. Slow growing oxides such as chromia and alumina are desirable. Once the oxide is formed it can prevent the metal from further reacting with its environment. Cyclic oxidation models the changes in temperature these wires will undergo in application. Cycling the temperature introduces thermal stresses which can cause the oxide layer to break off. Re-growth of the oxide layer consumes more metal and therefore reduces the properties and durability of the material. were used for cyclic oxidation testing. The baseline material, Haynes 188, has a Co base and is a chromia former while the other two alloys, Kanthal A1 and PM2000, both have a Fe base and are alumina formers. Haynes 188 and Kanthal A1 wires are 250 pm in diameter and PM2000 wires are 150 pm in diameter. The coiled wire has a total surface area of 3 to 5 sq cm. The wires were oxidized for 11 cycles at 1204 C, each cycle containing a 1 hour heating time and a minimum 20 minute cooling time. Weights were taken between cycles. After 11 cycles, one wire of each composition was removed for analysis. The other wire continued testing for 70 cycles. Post-test analysis includes X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) for phase identification and morphology.

  17. Effect of production microclimate on female thermal state with increased temperature and air humidity

    NASA Technical Reports Server (NTRS)

    Machablishvili, O. G.

    1980-01-01

    The thermal state of women during the effect of high air temperature and relative humidity with a varying degree of physical loads was studied. Parameters for air temperature, relative humidity, and air movement were established. It was established that in women the thermo-regulatory stress occurs at lower air temperatures and with lower physical loads than in men. The accumulation of heat in women was revealed with lower air temperature than in men. It is concluded that to preserve the normal physiological state of the female organism it is necessary to create more favorable microclimate conditions and decrease the physical loads.

  18. Diurnal temperature range trend over North Carolina and the associated mechanisms

    NASA Astrophysics Data System (ADS)

    Sayemuzzaman, Mohammad; Mekonnen, Ademe; Jha, Manoj K.

    2015-06-01

    This study seeks to investigate the variability and presence of trend in the diurnal surface air temperature range (DTR) over North Carolina (NC) for the period 1950-2009. The significance trend test and the magnitude of trends were determined using the non-parametric Mann-Kendall test and the Theil-Sen approach, respectively. Statewide significant trends (p < 0.05) of decreasing DTR were found in all seasons and annually during the analysis period. Highest (lowest) temporal DTR trends of magnitude - 0.19 (- 0.031) °C/decade were found in summer (winter). Potential mechanisms for the presence/absence of trend in DTR have been highlighted. Historical data sets of the three main moisture components (precipitation, total cloud cover (TCC), and soil moisture) and the two major atmospheric circulation modes (North Atlantic Oscillation and Southern Oscillation) were used for correlation analysis. The DTRs were found to be negatively correlated with the precipitation, TCC and soil moisture across the state for all the seasons and annual basis. It appears that the moisture components related better to the DTR than to the atmospheric circulation modes.

  19. Using Satellite-Based Spatiotemporal Resolved Air Temperature Exposure to Study the Association between Ambient Air Temperature and Birth Outcomes in Massachusetts

    PubMed Central

    Melly, Steven J.; Coull, Brent A.; Nordio, Francesco; Schwartz, Joel D.

    2015-01-01

    Background Studies looking at air temperature (Ta) and birth outcomes are rare. Objectives We investigated the association between birth outcomes and daily Ta during various prenatal exposure periods in Massachusetts (USA) using both traditional Ta stations and modeled addresses. Methods We evaluated birth outcomes and average daily Ta during various prenatal exposure periods in Massachusetts (USA) using both traditional Ta stations and modeled address Ta. We used linear and logistic mixed models and accelerated failure time models to estimate associations between Ta and the following outcomes among live births > 22 weeks: term birth weight (≥ 37 weeks), low birth weight (LBW; < 2,500 g at term), gestational age, and preterm delivery (PT; < 37 weeks). Models were adjusted for individual-level socioeconomic status, traffic density, particulate matter ≤ 2.5 μm (PM2.5), random intercept for census tract, and mother’s health. Results Predicted Ta during multiple time windows before birth was negatively associated with birth weight: Average birth weight was 16.7 g lower (95% CI: –29.7, –3.7) in association with an interquartile range increase (8.4°C) in Ta during the last trimester. Ta over the entire pregnancy was positively associated with PT [odds ratio (OR) = 1.02; 95% CI: 1.00, 1.05] and LBW (OR = 1.04; 95% CI: 0.96, 1.13). Conclusions Ta during pregnancy was associated with lower birth weight and shorter gestational age in our study population. Citation Kloog I, Melly SJ, Coull BA, Nordio F, Schwartz JD. 2015. Using satellite-based spatiotemporal resolved air temperature exposure to study the association between ambient air temperature and birth outcomes in Massachusetts. Environ Health Perspect 123:1053–1058; http://dx.doi.org/10.1289/ehp.1308075 PMID:25850104

  20. Impacts of wind farms on surface air temperatures

    PubMed Central

    Baidya Roy, Somnath; Traiteur, Justin J.

    2010-01-01

    Utility-scale large wind farms are rapidly growing in size and numbers all over the world. Data from a meteorological field campaign show that such wind farms can significantly affect near-surface air temperatures. These effects result from enhanced vertical mixing due to turbulence generated by wind turbine rotors. The impacts of wind farms on local weather can be minimized by changing rotor design or by siting wind farms in regions with high natural turbulence. Using a 25-y-long climate dataset, we identified such regions in the world. Many of these regions, such as the Midwest and Great Plains in the United States, are also rich in wind resources, making them ideal candidates for low-impact wind farms. PMID:20921371

  1. Impacts of wind farms on surface air temperatures.

    PubMed

    Baidya Roy, Somnath; Traiteur, Justin J

    2010-10-19

    Utility-scale large wind farms are rapidly growing in size and numbers all over the world. Data from a meteorological field campaign show that such wind farms can significantly affect near-surface air temperatures. These effects result from enhanced vertical mixing due to turbulence generated by wind turbine rotors. The impacts of wind farms on local weather can be minimized by changing rotor design or by siting wind farms in regions with high natural turbulence. Using a 25-y-long climate dataset, we identified such regions in the world. Many of these regions, such as the Midwest and Great Plains in the United States, are also rich in wind resources, making them ideal candidates for low-impact wind farms.

  2. Temperature coefficients of crystalline-quartz elastic constants over the cryogenic range [4 K, 15 K

    NASA Astrophysics Data System (ADS)

    Bon, Jérémy; Galliou, Serge; Bourquin, Roger

    2016-12-01

    This paper brings out the temperature coefficients of synthetic-quartz elastic constants at liquid helium temperature. The method is based on the relationship between the resonance frequencies of a quartz acoustic cavity and the elastic constants of the material. The temperature coefficients of the elastic constants are extracted from experimental frequency-temperature data collected within the very useful cryogenic range [4 K-15 K] from a set of resonators of various cut angles, because of the anisotropy of quartz.

  3. Alternate method for achieving temperature control in the -160 to +90 Celcius range

    NASA Technical Reports Server (NTRS)

    Johnson, Kenneth R. (Inventor)

    1995-01-01

    A single-pass method for accurate and precise temperature control in the -160 to +90 C range is discussed. The method exhibited minimal set-point overshoot during temperature transitions. Control to +/-2 C with transitions between set-points of 7 C per minute were achieved. The method uses commercially available temperature controllers and a gaseous nitrogen/liquid nitrogen mixer to dampen the amplitude of cold temperature spikes caused by liquid nitrogen pulsing.

  4. Bias Correction for Assimilation of Retrieved AIRS Profiles of Temperature and Humidity

    NASA Technical Reports Server (NTRS)

    Blankenship, Clay; Zavodsky, Brad; Blackwell, William

    2014-01-01

    Atmospheric Infrared Sounder (AIRS) is a hyperspectral radiometer aboard NASA's Aqua satellite designed to measure atmospheric profiles of temperature and humidity. AIRS retrievals are assimilated into the Weather Research and Forecasting (WRF) model over the North Pacific for some cases involving "atmospheric rivers". These events bring a large flux of water vapor to the west coast of North America and often lead to extreme precipitation in the coastal mountain ranges. An advantage of assimilating retrievals rather than radiances is that information in partly cloudy fields of view can be used. Two different Level 2 AIRS retrieval products are compared: the Version 6 AIRS Science Team standard retrievals and a neural net retrieval from MIT. Before assimilation, a bias correction is applied to adjust each layer of retrieved temperature and humidity so the layer mean values agree with a short-term model climatology. WRF runs assimilating each of the products are compared against each other and against a control run with no assimilation. This paper will describe the bias correction technique and results from forecasts evaluated by validation against a Total Precipitable Water (TPW) product from CIRA and against Global Forecast System (GFS) analyses.

  5. Bias Correction for Assimilation of Retrieved AIRS Profiles of Temperature and Humidity

    NASA Technical Reports Server (NTRS)

    Blakenship, Clay; Zavodsky, Bradley; Blackwell, William

    2014-01-01

    The Atmospheric Infrared Sounder (AIRS) is a hyperspectral radiometer aboard NASA's Aqua satellite designed to measure atmospheric profiles of temperature and humidity. AIRS retrievals are assimilated into the Weather Research and Forecasting (WRF) model over the North Pacific for some cases involving "atmospheric rivers". These events bring a large flux of water vapor to the west coast of North America and often lead to extreme precipitation in the coastal mountain ranges. An advantage of assimilating retrievals rather than radiances is that information in partly cloudy fields of view can be used. Two different Level 2 AIRS retrieval products are compared: the Version 6 AIRS Science Team standard retrievals and a neural net retrieval from MIT. Before assimilation, a bias correction is applied to adjust each layer of retrieved temperature and humidity so the layer mean values agree with a short-term model climatology. WRF runs assimilating each of the products are compared against each other and against a control run with no assimilation. Forecasts are against ERA reanalyses.

  6. Performance of Wide Operating Temperature Range Electrolytes in Quallion Prototype Li-Ion Cells

    NASA Technical Reports Server (NTRS)

    Smart, M. C.; Ratnakumar, B. V.; Tomcsi, M. R.; Nagata, M.; Visco, V.; Tsukamoto, H.

    2010-01-01

    For a number of applications, there is a continued interest in the development of rechargeable lithium-based batteries that can effectively operate over a wide temperature range (i.e., -40 to +70 deg C). These applications include powering future planetary rovers for NASA, enabling the next generation of automotive batteries for DOE, and supporting many DOD applications. Li-ion technology has been demonstrated to have good performance over a reasonably wide temperature range with many systems; however, there is still a desire to improve the low temperature rate capacity as well as the high temperature resilience. In the current study, we would like to present recent results obtained with prototype Li-Ion cells (manufactured by Quallion, LLC) which include various wide operating temperature range electrolytes developed by both JPL and Quallion. To demonstrate the viability of the technology, a number of performance tests were carried out, including: (a) discharge rate characterization over a wide temperature range (down to -60 deg C) using various rates (up to 20C rates), (b) discharge rate characterization at low temperatures with low temperature charging, (c) variable temperature cycling over a wide temperature range (-40 to +70 deg C), and (d) cycling at high temperature (50 deg C). As will be discussed, impressive rate capability was observed at low temperatures with many systems, as well as good resilience to high temperature cycling. To augment the performance testing on the prototype cells, a number of experimental three electrodes cells were fabricated (including Li reference electrodes) to allow the determination of the lithium kinetics of the respective electrodes and interfacial properties as a function of temperatures.

  7. Wide-Range Temperature Sensors with High-Level Pulse Train Output

    NASA Technical Reports Server (NTRS)

    Hammoud, Ahmad; Patterson, Richard L.

    2009-01-01

    Two types of temperature sensors have been developed for wide-range temperature applications. The two sensors measure temperature in the range of -190 to +200 C and utilize a thin-film platinum RTD (resistance temperature detector) as the temperature-sensing element. Other parts used in the fabrication of these sensors include NPO (negative-positive- zero) type ceramic capacitors for timing, thermally-stable film or wirewound resistors, and high-temperature circuit boards and solder. The first type of temperature sensor is a relaxation oscillator circuit using an SOI (silicon-on-insulator) operational amplifier as a comparator. The output is a pulse train with a period that is roughly proportional to the temperature being measured. The voltage level of the pulse train is high-level, for example 10 V. The high-level output makes the sensor less sensitive to noise or electromagnetic interference. The output can be read by a frequency or period meter and then converted into a temperature reading. The second type of temperature sensor is made up of various types of multivibrator circuits using an SOI type 555 timer and the passive components mentioned above. Three configurations have been developed that were based on the technique of charging and discharging a capacitor through a resistive element to create a train of pulses governed by the capacitor-resistor time constant. Both types of sensors, which operated successfully over the wide temperature range, have potential use in extreme temperature environments including jet engines and space exploration missions.

  8. The impact of seasonality in temperature on thermal tolerance and elevational range size.

    PubMed

    Sheldon, Kimberly S; Tewksbury, Joshua J

    2014-08-01

    Environmental temperature variation can influence physiology, biogeography, and life history, with large consequences for ecology, evolution, and the impacts of climate change. Based on the seasonality hypothesis, greater annual temperature variation at high latitudes should result in greater thermal tolerance and, consequently, larger elevational ranges in temperate compared to tropical species. Despite the mechanistic nature of this hypothesis, most research has used latitude as a proxy for seasonality, failing to directly examine the impact of temperature variation on physiology and range size. We used phylogenetically matched beetles from locations spanning 60 degrees of latitude to explore links between seasonality, physiology and elevational range. Thermal tolerance increased with seasonality across all beetle groups, but realized seasonality (temperature variation restricted to the months species are active) was a better predictor of thermal tolerance than was annual seasonality. Additionally, beetles with greater thermal tolerance had larger elevational ranges. Our results support a mechanistic framework linking variation in realized temperature to physiology and distributions.

  9. 'Optimal thermal range' in ectotherms: Defining criteria for tests of the temperature-size-rule.

    PubMed

    Walczyńska, Aleksandra; Kiełbasa, Anna; Sobczyk, Mateusz

    2016-08-01

    Thermal performance curves for population growth rate r (a measure of fitness) were estimated over a wide range of temperature for three species: Coleps hirtus (Protista), Lecane inermis (Rotifera) and Aeolosoma hemprichi (Oligochaeta). We measured individual body size and examined if predictions for the temperature-size rule (TSR) were valid for different temperatures. All three organisms investigated follow the TSR, but only over a specific range between minimal and optimal temperatures, while maintenance at temperatures beyond this range showed the opposite pattern in these taxa. We consider minimal and optimal temperatures to be species-specific, and moreover delineate a physiological range outside of which an ectotherm is constrained against displaying size plasticity in response to temperature. This thermal range concept has important implications for general size-temperature studies. Furthermore, the concept of 'operating thermal conditions' may provide a new approach to (i) defining criteria required for investigating and interpreting temperature effects, and (ii) providing a novel interpretation for many cases in which species do not conform to the TSR.

  10. Regression analysis in modeling of air surface temperature and factors affecting its value in Peninsular Malaysia

    NASA Astrophysics Data System (ADS)

    Rajab, Jasim Mohammed; Jafri, Mohd. Zubir Mat; Lim, Hwee San; Abdullah, Khiruddin

    2012-10-01

    This study encompasses air surface temperature (AST) modeling in the lower atmosphere. Data of four atmosphere pollutant gases (CO, O3, CH4, and H2O) dataset, retrieved from the National Aeronautics and Space Administration Atmospheric Infrared Sounder (AIRS), from 2003 to 2008 was employed to develop a model to predict AST value in the Malaysian peninsula using the multiple regression method. For the entire period, the pollutants were highly correlated (R=0.821) with predicted AST. Comparisons among five stations in 2009 showed close agreement between the predicted AST and the observed AST from AIRS, especially in the southwest monsoon (SWM) season, within 1.3 K, and for in situ data, within 1 to 2 K. The validation results of AST with AST from AIRS showed high correlation coefficient (R=0.845 to 0.918), indicating the model's efficiency and accuracy. Statistical analysis in terms of β showed that H2O (0.565 to 1.746) tended to contribute significantly to high AST values during the northeast monsoon season. Generally, these results clearly indicate the advantage of using the satellite AIRS data and a correlation analysis study to investigate the impact of atmospheric greenhouse gases on AST over the Malaysian peninsula. A model was developed that is capable of retrieving the Malaysian peninsulan AST in all weather conditions, with total uncertainties ranging between 1 and 2 K.

  11. 33 CFR 334.1180 - Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. 334.1180 Section 334.1180 Navigation and Navigable... REGULATIONS § 334.1180 Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. (a)...

  12. 33 CFR 334.1180 - Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. 334.1180 Section 334.1180 Navigation and Navigable... REGULATIONS § 334.1180 Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. (a)...

  13. 33 CFR 334.1180 - Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. 334.1180 Section 334.1180 Navigation and Navigable... REGULATIONS § 334.1180 Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. (a)...

  14. 33 CFR 334.1180 - Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. 334.1180 Section 334.1180 Navigation and Navigable... REGULATIONS § 334.1180 Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. (a)...

  15. 33 CFR 334.1180 - Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. 334.1180 Section 334.1180 Navigation and Navigable... REGULATIONS § 334.1180 Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. (a)...

  16. The Front Range Air Pollution and Photochemistry Experiment (FRAPPE) - an overview

    NASA Astrophysics Data System (ADS)

    Flocke, F. M.; Science Teams, F A D A

    2015-12-01

    The Front Range Air Pollution and Photochemistry Experiment (FRAPPÉ) was designed to quantify the factors controlling surface ozone in the Northern Front Range Metropolitan Area (NFRMA) and determine whether current and planned emission controls are sufficient to reduce ozone levels below standards. The experiment was conducted simultaneously with the 2014 DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) intensive, and employed a coordinated set of ground-based, aircraft-based and satellite measurements. The NFRMA is subject to emissions from a wide variety of very diverse sources such as transportation, power generation, agriculture and livestock operations, oil and gas extraction activities, and natural emissions from vegetation. Inflow into the state can contain elevated ozone brought about from emissions originating from other Western states, Canada or Asia. Terrain-induced, complex mountain-valley circulation patterns, can, to some extent, recirculate polluted air and exacerbate high ozone events. This transport also contributes to high ozone, visibility degradation, and deposition of pollution into Rocky Mountain National Park and other pristine areas. Fifteen flights were performed between July 26 and August 17, 2014, on board the NCAR/NSF C-130 research aircraft, which was equipped with a comprehensive gas phase photochemistry and aerosol payload. The C-130 flights covered much of the State of Colorado. Numerous ground sites and mobile labs were taking measurements simultaneously, and the NASA P3, B-200, and Falcon aircraft flight operations were concentrated on the NFRMA itself. This presentation will summarize the FRAPPÉ activities and present first results with respect to emission characterization of the area and comparison with inventories, contributions of emission source types to ozone production and particle composition, transport and chemical evolution of air masses

  17. Combustion and gasification characteristics of pulverized coal using high-temperature air

    SciTech Connect

    Hanaoka, R.; Nakamura, M.; Kiga, T.; Kosaka, H.; Iwahashi, T.; Yoshikawa, K.; Sakai, M.; Muramatsu, K.; Mochida, S.

    1998-07-01

    In order to confirm performance of high-temperature-air combusting of pulverized coal, laboratory-scale combustion and gasification tests of coal were conducted changing air temperature and oxygen concentration in the air. Theses were conducted in a drop tube furnace of 200mm in inside diameter and 2,000mm in length. The furnace was heated by ceramic heater up to 1,300 C. A high-temperature air preheater utilizing the HRS (High Cycle Regenerative Combustion System) was used to obtain high-temperature combustion air. As the results, NOx emission was reduced when pulverized coal was fired with high-temperature-air. On the other hand, by lower oxygen concentration in combustion air diluted by nitrogen, NOx emission slightly decreased while became higher under staging condition.

  18. Experimental study of the decrease in the temperature of an air/water-cooled turbine blade

    NASA Astrophysics Data System (ADS)

    Ryzhov, A. A.; Sereda, A. V.; Shaiakberov, V. F.; Iskakov, K. M.; Shatalov, Iu. S.

    Results of the full-scale testing of an air/water-cooled deflector-type turbine blade are reported. Data on the decrease in the temperature of the cooling air and of the blade are presented and compared with the calculated values. An analysis of the results indicates that the use of air/water cooling makes it possible to significantly reduce the temperature of the cooling air and of the blade with practically no increase in the engine weight and dimensions.

  19. How the Plant Temperature Links to the Air Temperature in the Desert Plant Artemisia ordosica.

    PubMed

    Yu, Ming-Han; Ding, Guo-Dong; Gao, Guang-Lei; Sun, Bao-Ping; Zhao, Yuan-Yuan; Wan, Li; Wang, De-Ying; Gui, Zi-Yang

    2015-01-01

    Plant temperature (Tp) is an important indicator of plant health. To determine the dynamics of plant temperature and self-cooling ability of the plant, we measured Tp in Artemisia ordosica in July, in the Mu Us Desert of Northwest China. Related factors were also monitored to investigate their effects on Tp, including environmental factors, such as air temperature (Ta), relative humidity, wind speed; and physiological factors, such as leaf water potential, sap flow, and water content. The results indicate that: 1) Tp generally changes in conjunction with Ta mainly, and varies with height and among the plant organs. Tp in the young branches is most constant, while it is the most sensitive in the leaves. 2) Correlations between Tp and environmental factors show that Tp is affected mainly by Ta. 3) The self-cooling ability of the plant was effective by midday, with Tp being lower than Ta. 4) Increasing sap flow and leaf water potential showed that transpiration formed part of the mechanism that supported self-cooling. Increased in water conductance and specific heat at midday may be additional factors that contribute to plant cooling ability. Therefore, our results confirmed plant self-cooling ability. The response to high temperatures is regulated by both transpiration speed and an increase in stem water conductance. This study provides quantitative data for plant management in terms of temperature control. Moreover, our findings will assist species selection with taking plant temperature as an index.

  20. Dynamics of Air Temperature, Velocity and Ammonia Emissions in Enclosed and Conventional Pig Housing Systems

    PubMed Central

    Song, J. I.; Park, K.-H.; Jeon, J. H.; Choi, H. L.; Barroga, A. J.

    2013-01-01

    This study aimed to compare the dynamics of air temperature and velocity under two different ventilation and housing systems during summer and winter in Korea. The NH3 concentration of both housing systems was also investigated in relation to the pig’s growth. The ventilation systems used were; negative pressure type for the enclosed pig house (EPH) and natural airflow for the conventional pig house (CPH). Against a highly fluctuating outdoor temperature, the EPH was able to maintain a stable temperature at 24.8 to 29.1°C during summer and 17.9 to 23.1°C during winter whilst the CPH had a wider temperature variance during summer at 24.7 to 32.3°C. However, the temperature fluctuation of the CPH during winter was almost the same with that of EPH at 14.5 to 18.2°C. The NH3 levels in the CPH ranged from 9.31 to 16.9 mg/L during summer and 5.1 to 19.7 mg/L during winter whilst that of the EPH pig house was 7.9 to 16.1 mg/L and 3.7 to 9.6 mg/L during summer and winter, respectively. These values were less than the critical ammonia level for pigs with the EPH maintaining a lower level than the CPH in both winter and summer. The air velocity at pig nose level in the EPH during summer was 0.23 m/s, enough to provide comfort because of the unique design of the inlet feature. However, no air movement was observed in almost all the lower portions of the CPH during winter because of the absence of an inlet feature. There was a significant improvement in weight gain and feed intake of pigs reared in the EPH compared to the CPH (p<0.05). These findings proved that despite the difference in the housing systems, a stable indoor temperature was necessary to minimize the impact of an avoidable and highly fluctuating outdoor temperature. The EPH consistently maintained an effective indoor airspeed irrespective of season; however the CPH had defective and stagnant air at pig nose level during winter. Characteristics of airflow direction and pattern were consistent relative to

  1. Measured Performance of a Low Temperature Air Source Heat Pump

    SciTech Connect

    Johnson, R. K.

    2013-09-01

    A 4-ton Low Temperature Heat Pump (LTHP) manufactured by Hallowell International was installed in a residence near New Haven, Connecticut and monitored over two winters of operation. After attending to some significant service issues, the heat pump operated as designed. This report should be considered a review of the dual compressor 'boosted heat pump' technology. The Low Temperature Heat Pumpsystem operates with four increasing levels of capacity (heat output) as the outdoor temperature drops. The system was shown to select capacity correctly, supplying the appropriate amount of heat to the house across the full range of outdoor temperatures. The system's Coefficient of Performance (Seasonal COP, or SCOP) over two entire winters was calculated, based on measured data, to be 3.29over the first winter and 2.68 over the second winter. A second seasonal efficiency calculation by a different method yielded a SCOP of 2.78 for the first winter and 2.83 for the second winter. This second seasonal efficiency calculation was determined by comparing measured heat pump energy use to the in situ energy use with resistance heat alone. This method is the ratio of the slopes of thedaily energy use load lines.

  2. The solubility of hydrogen in plutonium in the temperature range 475 to 825 degrees centigrade

    SciTech Connect

    Allen, T.H.

    1991-01-01

    The solubility of hydrogen (H) in plutonium metal (Pu) was measured in the temperature range of 475 to 825{degree}C for unalloyed Pu (UA) and in the temperature range of 475 to 625{degree}C for Pu containing two-weight-percent gallium (TWP). For TWP metal, in the temperature range 475 to 600{degree}C, the saturated solution has a maximum hydrogen to plutonium ration (H/Pu) of 0.00998 and the standard enthalpy of formation ({Delta}H{degree}{sub f(s)}) is (-0.128 {plus minus} 0.0123) kcal/mol. The phase boundary of the solid solution in equilibrium with plutonium dihydride (PuH{sub 2}) is temperature independent. In the temperature range 475 to 625{degree}C, UA metal has a maximum solubility at H/Pu = 0.011. The phase boundary between the solid solution region and the metal+PuH{sub 2} two-phase region is temperature dependent. The solubility of hydrogen in UA metal was also measured in the temperature range 650 to 825{degree}C with {Delta}H{degree}{sub f(s)} = (-0.104 {plus minus} 0.0143) kcal/mol and {Delta}S{degree}{sub f(s)} = 0. The phase boundary is temperature dependent and the maximum hydrogen solubility has H/Pu = 0.0674 at 825{degree}C. 52 refs., 28 figs., 9 tabs.

  3. Environmentally sound thermal energy extraction from coal and wastes using high temperature air combustion technology

    SciTech Connect

    Yoshikawa, Kunio

    1999-07-01

    High temperature air combustion is one of promising ways of burning relatively low BTU gas obtained from gasification of low grade coal or wastes. In this report, the author proposes a new power generation system coupled with high temperature air gasification of coal/wastes and high temperature air combustion of the syngas from coal/wastes. This system is realized by employing Multi-staged Enthalpy Extraction Technology (MEET). The basic idea of the MEET system is that coal or wastes are gasified with high temperature air of about 1,000 C, then the generated syngas is cooled in a heat recovery boiler to be cleaned-up in a gas cleanup system (desulfurization, desalinization and dust removal). Part of thermal energy contained in this cleaned-up syngas is used for high temperature air preheating, and the complete combustion of the fuel gas is done using also high temperature air for driving gas turbines or steam generation in a boiler.

  4. Temporal and spatial assessments of minimum air temperature using satellite surface temperature measurements in Massachusetts, USA

    PubMed Central

    Kloog, Itai; Chudnovsky, Alexandra; Koutrakis, Petros; Schwartz, Joel

    2015-01-01

    Although meteorological stations provide accurate air temperature observations, their spatial coverage is limited and thus often insufficient for epidemiological studies. Satellite data expand spatial coverage, enhancing our ability to estimate near surface air temperature (Ta). However, the derivation of Ta from surface temperature (Ts) measured by satellites is far from being straightforward. In this study, we present a novel approach that incorporates land use regression, meteorological variables and spatial smoothing to first calibrate between Ts and Ta on a daily basis and then predict Ta for days when satellite Ts data were not available. We applied mixed regression models with daily random slopes to calibrate Moderate Resolution Imaging Spectroradiometer (MODIS) Ts data with monitored Ta measurements for 2003. Then, we used a generalized additive mixed model with spatial smoothing to estimate Ta in days with missing Ts. Out-of-sample tenfold cross-validation was used to quantify the accuracy of our predictions. Our model performance was excellent for both days with available Ts and days without Ts observations (mean out-of-sample R2=0.946 and R2=0.941 respectively). Furthermore, based on the high quality predictions we investigated the spatial patterns of Ta within the study domain as they relate to urban vs. non-urban land uses. PMID:22721687

  5. Temporal and spatial assessments of minimum air temperature using satellite surface temperature measurements in Massachusetts, USA.

    PubMed

    Kloog, Itai; Chudnovsky, Alexandra; Koutrakis, Petros; Schwartz, Joel

    2012-08-15

    Although meteorological stations provide accurate air temperature observations, their spatial coverage is limited and thus often insufficient for epidemiological studies. Satellite data expand spatial coverage, enhancing our ability to estimate near surface air temperature (Ta). However, the derivation of Ta from surface temperature (Ts) measured by satellites is far from being straightforward. In this study, we present a novel approach that incorporates land use regression, meteorological variables and spatial smoothing to first calibrate between Ts and Ta on a daily basis and then predict Ta for days when satellite Ts data were not available. We applied mixed regression models with daily random slopes to calibrate Moderate Resolution Imaging Spectroradiometer (MODIS) Ts data with monitored Ta measurements for 2003. Then, we used a generalized additive mixed model with spatial smoothing to estimate Ta in days with missing Ts. Out-of-sample tenfold cross-validation was used to quantify the accuracy of our predictions. Our model performance was excellent for both days with available Ts and days without Ts observations (mean out-of-sample R(2)=0.946 and R(2)=0.941 respectively). Furthermore, based on the high quality predictions we investigated the spatial patterns of Ta within the study domain as they relate to urban vs. non-urban land uses.

  6. Increases in air temperature can promote wind-driven dispersal and spread of plants.

    PubMed

    Kuparinen, Anna; Katul, Gabriel; Nathan, Ran; Schurr, Frank M

    2009-09-07

    Long-distance dispersal (LDD) of seeds and pollen shapes the spatial dynamics of plant genotypes, populations and communities. Quantifying LDD is thus important for predicting the future dynamics of plants exposed to environmental changes. However, environmental changes can also alter the behaviour of LDD vectors: for instance, increasing air temperature may enhance atmospheric instability, thereby altering the turbulent airflow that transports seed and pollen. Here, we investigate temperature effects on wind dispersal in a boreal forest using a 10-year time series of micrometeorological measurements and a Lagrangian stochastic model for particle transport. For a wide range of dispersal and life history types, we found positive relations between air temperature and LDD. This translates into a largely consistent positive effect of +3 degrees C warming on predicted LDD frequencies and spread rates of plants. Relative increases in LDD frequency tend to be higher for heavy-seeded plants, whereas absolute increases in LDD and spread rates are higher for light-seeded plants for which wind is often an important dispersal vector. While these predicted increases are not sufficient to compensate forecasted range losses and environmental changes can alter plant spread in various ways, our results generally suggest that warming can promote wind-driven movements of plant genotypes and populations in boreal forests.

  7. Temperature Dependence of Thin Film Spiral Inductors on Alumina Over a Temperature Range of 25 to 475 C

    NASA Technical Reports Server (NTRS)

    Ponchak, George E.; Jordan, Jennifer L.; Scardelletti, Maximilian C.

    2010-01-01

    In this paper, we present an analysis of inductors on an Alumina substrate over the temperature range of 25 to 475 C. Five sets of inductors, each set consisting of a 1.5, 2.5, 3.5, and a 4.5 turn inductor with different line width and spacing, were measured on a high temperature probe station from 10 MHz to 30 GHz. From these measured characteristics, it is shown that the inductance is nearly independent of temperature for low frequencies compared to the self resonant frequency, the parasitic capacitances are independent of temperature, and the resistance varies nearly linearly with temperature. These characteristics result in the self resonant frequency decreasing by only a few percent as the temperature is increased from 25 to 475 C, but the maximum quality factor decreases by a factor of 2 to 3. These observations based on measured data are confirmed through 2D simulations using Sonnet software.

  8. The direction and range of ambient temperature change influences yawning in budgerigars (Melopsittacus undulatus).

    PubMed

    Gallup, Andrew C; Miller, Michael L; Clark, Anne B

    2010-05-01

    Comparative research suggests that yawning is a thermoregulatory behavior in homeotherms. Our previous experiments revealed that yawning increased in budgerigars (Melopsittacus undulatus) as ambient temperature was raised toward body temperature (22-->34 degrees C). In this study, we identify the range of temperatures that triggers yawning to rule out the possible effect of changing temperature in any range. To corroborate its thermoregulatory function, we also related the incidence of yawning to other avian thermoregulatory behaviors in budgerigars (e.g., panting, wing venting). In a repeated measures design, 16 budgerigars were exposed to 4 separate 10-min periods of changing temperatures: (a) low-increasing (23-->27 degrees C), (b) high-increasing (27-->33 degrees C), (c) high-decreasing (34-->28 degrees C), and (d) low-decreasing (28-->24 degrees C). Birds yawned significantly more during the high-increasing temperature range, and yawning was positively correlated with ambient temperature across trials. Yawning was also positively correlated with other thermoregulatory behaviors. This research clarifies the previously demonstrated relationship between yawning rate and temperature by providing evidence that the physiological trigger for yawning is related to increasing body temperatures rather than the detection of changing external temperatures.

  9. Simultaneous Measurement of Air Temperature and Humidity Based on Sound Velocity and Attenuation Using Ultrasonic Probe

    NASA Astrophysics Data System (ADS)

    Motegi, Takahiro; Mizutani, Koichi; Wakatsuki, Naoto

    2013-07-01

    In this paper, an acoustic technique for air temperature and humidity measurement in moist air is described. The previous ultrasonic probe can enable the estimation of temperature from sound velocity in dry air by making use of the relationship between sound velocity and temperature. However, temperature measurement using the previous ultrasonic probe is not suitable in moist air because sound velocity also depends on humidity, and the temperature estimated from the sound velocity measured in moist air must be adjusted. Moreover, a method of humidity measurement by using only an ultrasonic probe has not been established. Thus, we focus on sound attenuation, which depends on temperature and humidity. Our proposed technique utilizes two parameters, sound velocity and attenuation, and can measure both temperature and humidity simultaneously. The acoustic technique for temperature and humidity measurement has the advantages that instantaneous temperature and humidity can be measured, and the measurement is not affected by thermal radiation because air itself is used as a sensing element. As an experiment, temperature and humidity are measured in a chamber, and compared with the reference values. The experimental results indicate the achievement of a practical temperature measurement accuracy of within +/-0.5 K in moist air, of which the temperature is 293-308 K and relative humidity (RH) is 50-90% RH, and the simultaneous measurement of temperature and humidity.

  10. The impact of AIRS atmospheric temperature and moisture profiles on hurricane forecasts: Ike (2008) and Irene (2011)

    NASA Astrophysics Data System (ADS)

    Zheng, Jing; Li, Jun; Schmit, Timothy J.; Li, Jinlong; Liu, Zhiquan

    2015-03-01

    Atmospheric InfraRed Sounder (AIRS) measurements are a valuable supplement to current observational data, especially over the oceans where conventional data are sparse. In this study, two types of AIRS-retrieved temperature and moisture profiles, the AIRS Science Team product (SciSup) and the single field-of-view (SFOV) research product, were evaluated with European Centre for Medium-Range Weather Forecasts (ECMWF) analysis data over the Atlantic Ocean during Hurricane Ike (2008) and Hurricane Irene (2011). The evaluation results showed that both types of AIRS profiles agreed well with the ECMWF analysis, especially between 200 hPa and 700 hPa. The average standard deviation of both temperature profiles was approximately 1 K under 200 hPa, where the mean AIRS temperature profile from the AIRS SciSup retrievals was slightly colder than that from the AIRS SFOV retrievals. The mean SciSup moisture profile was slightly drier than that from the SFOV in the mid troposphere. A series of data assimilation and forecast experiments was then conducted with the Advanced Research version of the Weather Research and Forecasting (WRF) model and its three-dimensional variational (3DVAR) data assimilation system for hurricanes Ike and Irene. The results showed an improvement in the hurricane track due to the assimilation of AIRS clear-sky temperature profiles in the hurricane environment. In terms of total precipitable water and rainfall forecasts, the hurricane moisture environment was found to be affected by the AIRS sounding assimilation. Meanwhile, improving hurricane intensity forecasts through assimilating AIRS profiles remains a challenge for further study.

  11. Impacts of the Denver Cyclone on Regional Air Quality and Aerosol Formation in the Colorado Front Range during the Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ) 2014

    NASA Astrophysics Data System (ADS)

    Vu, K. K. T.; Dingle, J. H.; Bahreini, R.; Apel, E. C.; Campos, T. L.; Cantrell, C. A.; Flocke, F. M.; Fried, A.; Herndon, S. C.; Hills, A. J.; Hornbrook, R. S.; Huey, L. G.; Kaser, L.; Mauldin, L.; Montzka, D. D.; Nowak, J. B.; Richter, D.; Roscioli, J. R.; Shertz, S.; Stell, M. H.; Tanner, D.; Tyndall, G. S.; Walega, J.; Weibring, P.; Weinheimer, A. J.

    2015-12-01

    The northern Colorado Front Range continues to face challenges related to air quality, specifically ozone, and has been classified as a marginal non-attainment area by the U.S EPA. The highly complex topography and meteorology in the Colorado Front Range provide flow patterns that are driven by mountain-valley circulation, resulting in formation of the Denver Cyclone, strongly influencing concentrations of ozone and aerosol particles. However, the impact of the Denver Cyclone on aerosol formation has not been previously explored. In this study, airborne measurements were made during July 16 - August 18, 2014 aboard the NSF C-130 aircraft during the 2014 Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ) project. We carried out fast time resolved measurements of ambient aerosol chemical constituents (organics, sulfate, nitrate, ammonium, and chloride) of non-refractory sub-micrometer particles using an Aerodyne compact time-of-flight aerosol mass spectrometer (mAMS). Pronounced increased mass concentrations of organics, nitrate, and sulfate in two distinct regions in the Front Range were observed during the cyclone episodes, in contrast to the non-cyclonic days. Organics dominated the mass concentrations on all days evaluated. The average mass concentration of organics during a cyclone event was 5.79 ± 1.48 μg·m-3 and were lower during the two non-cyclonic measurement days, 3.09 ± 1.18 μg·m-3. Average sulfate mass concentrations were 1.25 ± 0.41 μg·m-3 vs. 0.58 ± 0.20 μg·m-3 followed by nitrate with an average of 1.66 ± 0.92 μg·m-3 vs. 0.32 ± 0.41 μg·m-3 on cyclone vs. non-cyclonic days, respectively. Correlations between trace gas markers (carbon monoxide, nitrogen oxides, ozone, ammonia, and ethane), meteorological variables (relative humidity, temperature), and the extent of aerosol aging are evaluated and used to assess the Front Range aerosol formation and air quality impacts in the region during these events.

  12. Research Update: Direct conversion of amorphous carbon into diamond at ambient pressures and temperatures in air

    SciTech Connect

    Narayan, Jagdish Bhaumik, Anagh

    2015-10-01

    We report on fundamental discovery of conversion of amorphous carbon into diamond by irradiating amorphous carbon films with nanosecond lasers at room-temperature in air at atmospheric pressure. We can create diamond in the form of nanodiamond (size range <100 nm) and microdiamond (>100 nm). Nanosecond laser pulses are used to melt amorphous diamondlike carbon and create a highly undercooled state, from which various forms of diamond can be formed upon cooling. The quenching from the super undercooled state results in nucleation of nanodiamond. It is found that microdiamonds grow out of highly undercooled state of carbon, with nanodiamond acting as seed crystals.

  13. Origin of reverse-graded bedding in air-fall pumice, Coso Range, California

    USGS Publications Warehouse

    Duffield, W.A.; Bacon, C.R.; Roquemore, G.R.

    1979-01-01

    The origin of reverse grading in air-fall pyroclastic deposits has been ascribed to: (1) changing conditions at an erupting vent; (2) deposition in water; or (3) rolling of large clasts over smaller clasts on the surface of a steep slope. Structural features in a deposit of air-fall pumice lapilli in the Coso Range, California, indicate that reverse grading there formed by a fourth mechanism during flow of pumice. Reverse-graded beds in this deposit occur where pumice lapilli fell on slopes at or near the angle of repose and formed as parts of the blanket of accumulating pumice became unstable and flowed downslope. The process of size sorting during such flow is probably analogous to that which sorts sand grains in a reverse fashion during avalanching on the slip faces of sand dunes, attributed by Bagnold (1954a) to a grain-dispersive pressure acting on particles subjected to a shear stress. In view of the several ways in which air-fall pyroclastic debris may become reverse graded, caution is advised in interpretation of the origin of this structure both in modern and in ancient deposits. ?? 1979.

  14. Diurnal temperature range compression hastens berry development and modifies flavonoid partitioning in grapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Temperatures during the day and night are known to influence grape berry metabolism and resulting composition. In this study, the flavonoid composition of field-grown Vitis vinifera L. cv. Merlot berries was investigated as a function of diurnal temperature range (DTR). The DTR was compressed by c...

  15. Serial temperature monitoring and comparison of rectal and muscle temperatures in immobilized free-ranging black rhinoceros (Diceros bicornis).

    PubMed

    vdB Morkel, Peter; Miller, Michele; Jago, Mark; Radcliffe, Robin W; du Preez, Pierre; Olea-Popelka, Francisco; Sefton, Jennifer; Taft, Arthur; Nydam, Daryl; Gleed, Robin D

    2012-03-01

    Control of body temperature is critical to a successful anesthetic outcome, particularly during field immobilization of wild animals. Hyperthermia associated with exertion can lead to serious and potentially life-threatening complications such as organ damage (including myopathy) and death. Methods for monitoring core body temperature must accurately reflect the physiologic status of the animal in order for interventions to be effective. The goal of this preliminary study was to compare serial rectal and muscle temperatures in field-immobilized black rhinoceros (Diceros bicornis) and evaluate a possible association. Twenty-four free-ranging black rhinoceros were immobilized between February and March of 2010 in Ethosha National Park, Namibia. Pairwise comparisons showed a correlation of 0.73 (95% CI; 0.70-0.75) between rectal and muscle temperature measurements. Results from a multivariable model indicate that muscle temperature readings were, on average, 0.46 degrees C (95% CI; 0.36-0.57 degrees C) higher than rectal temperatures while adjusting for repeated measurements on the same rhinoceros, effect of duration of immobilization, and effect of ambient temperature on rhinoceroses' temperature readings. As immobilization time increased, muscle and rectal temperature values within an individual rhinoceros tended to equilibrate. The overall temperatures decreased by an average of 0.00059 degrees C/min (95% CI; -0.0047 to -0.0035 degrees C/min; P = 0.779). As the ambient temperature at time of immobilization increased by 1 degree C, the average rhinoceros temperature increased by 0.09 degrees C (95% CI; 0.06-0.11 degrees C, P < 0.0001). Higher body temperature creates a potential for cellular damage leading to complications that include myopathy. Methods for monitoring rectal, muscle, and ambient temperatures should be incorporated into anesthetic monitoring protocols for large ungulates, particularly under field conditions.

  16. Experimental study and improved modeling of high-temperature air radiation

    NASA Technical Reports Server (NTRS)

    Laux, Christophe O.; Moreau, Stephane; Kruger, Charles H.

    1992-01-01

    Spectral emission measurements were conducted in an atmospheric pressure air plasma. The thermodynamic state of the plasma was determined to be close to local thermodynamic equilibrium (LTE), and the temperature profile was measured. The spectrum emitted by the plasma over the range 2,000 to 8,000 A was recorded and calibrated. This spectrum comprises the major radiating molecular bands and atomic lines in air, and is therefore proposed as a benchmark to test radiative calculations. A comparison of these results with the predictions of the NEQAIR code induced several modeling improvements in the code. In particular, radiative transition probabilities and spectroscopic constants were updated, and additional band systems of NO (NO Delta, Epsilon, Beta prime and Gamma prime) were included. Since the C state from which the NO Delta transition originates is predissociated, a simplified collision-predissociation model for this state was added to the code. These changes are presented, and their effect discussed.

  17. Mangrove expansion and contraction at a poleward range limit: Climate extremes and land-ocean temperature gradients

    USGS Publications Warehouse

    Osland, Michael J.; Day, Richard H.; Hall, Courtney T.; Brumfield, Marisa D; Dugas, Jason; Jones, William R.

    2017-01-01

    Within the context of climate change, there is a pressing need to better understand the ecological implications of changes in the frequency and intensity of climate extremes. Along subtropical coasts, less frequent and warmer freeze events are expected to permit freeze-sensitive mangrove forests to expand poleward and displace freeze-tolerant salt marshes. Here, our aim was to better understand the drivers of poleward mangrove migration by quantifying spatiotemporal patterns in mangrove range expansion and contraction across land-ocean temperature gradients. Our work was conducted in a freeze-sensitive mangrove-marsh transition zone that spans a land-ocean temperature gradient in one of the world's most wetland-rich regions (Mississippi River Deltaic Plain; Louisiana, USA). We used historical air temperature data (1893-2014), alternative future climate scenarios, and coastal wetland coverage data (1978-2011) to investigate spatiotemporal fluctuations and climate-wetland linkages. Our analyses indicate that changes in mangrove coverage have been controlled primarily by extreme freeze events (i.e., air temperatures below a threshold zone of -6.3 to -7.6 °C). We expect that in the past 121 years, mangrove range expansion and contraction has occurred across land-ocean temperature gradients. Mangrove resistance, resilience, and dominance were all highest in areas closer to the ocean where temperature extremes were buffered by large expanses of water and saturated soil. Under climate change, these areas will likely serve as local hotspots for mangrove dispersal, growth, range expansion, and displacement of salt marsh. Collectively, our results show that the frequency and intensity of freeze events across land-ocean temperature gradients greatly influences spatiotemporal patterns of range expansion and contraction of freeze-sensitive mangroves. We expect that, along subtropical coasts, similar processes govern the distribution and abundance of other freeze

  18. Mangrove expansion and contraction at a poleward range limit: climate extremes and land-ocean temperature gradients.

    PubMed

    Osland, Michael J; Day, Richard H; Hall, Courtney T; Brumfield, Marisa D; Dugas, Jason L; Jones, William R

    2017-01-01

    Within the context of climate change, there is a pressing need to better understand the ecological implications of changes in the frequency and intensity of climate extremes. Along subtropical coasts, less frequent and warmer freeze events are expected to permit freeze-sensitive mangrove forests to expand poleward and displace freeze-tolerant salt marshes. Here, our aim was to better understand the drivers of poleward mangrove migration by quantifying spatiotemporal patterns in mangrove range expansion and contraction across land-ocean temperature gradients. Our work was conducted in a freeze-sensitive mangrove-marsh transition zone that spans a land-ocean temperature gradient in one of the world's most wetland-rich regions (Mississippi River Deltaic Plain; Louisiana, USA). We used historical air temperature data (1893-2014), alternative future climate scenarios, and coastal wetland coverage data (1978-2011) to investigate spatiotemporal fluctuations and climate-wetland linkages. Our analyses indicate that changes in mangrove coverage have been controlled primarily by extreme freeze events (i.e., air temperatures below a threshold zone of -6.3 to -7.6°C). We expect that in the past 121 yr, mangrove range expansion and contraction has occurred across land-ocean temperature gradients. Mangrove resistance, resilience, and dominance were all highest in areas closer to the ocean where temperature extremes were buffered by large expanses of water and saturated soil. Under climate change, these areas will likely serve as local hotspots for mangrove dispersal, growth, range expansion, and displacement of salt marsh. Collectively, our results show that the frequency and intensity of freeze events across land-ocean temperature gradients greatly influences spatiotemporal patterns of range expansion and contraction of freeze-sensitive mangroves. We expect that, along subtropical coasts, similar processes govern the distribution and abundance of other freeze

  19. Final Environmental Assessment for the Installation of a Range Safety Lighting System at Avon Park Air Force Range, Florida

    DTIC Science & Technology

    2010-08-01

    Sterna antillarum N T Mammals Florida panther Puma concolor coryi E E Florida black bear Ursus americanus floridans N T Reptiles and Amphibians ...Casuarina glauca Australian pine Dioscorea bulbifera Air potato Eichhornia crassipes Water hyacinth Eugenia uniflora Surinam cherry Hydrilla...Cuban treefrog (Osteophilus septentrionalis), Cuban brown anole (Anole sagrei) and the Indo-Pacific gecko (Hemidactylus garnoti) are some amphibian and

  20. Analytical evaluation of effect of equivalence ratio inlet-air temperature and combustion pressure on performance of several possible ram-jet fuels

    NASA Technical Reports Server (NTRS)

    Tower, Leonard K; Gammon, Benson E

    1953-01-01

    The results of an analytical investigation of the theoretical air specific impulse performance and adiabatic combustion temperatures of several possible ram-jet fuels over a range of equivalence ratios, inlet-air temperatures, and combustion pressures, is presented herein. The fuels include octane-1, 50-percent-magnesium slurry, boron, pentaborane, diborane, hydrogen, carbon, and aluminum. Thermal effects from high combustion temperatures were found to effect considerably the combustion performance of all the fuels. An increase in combustion pressure was beneficial to air specific impulse at high combustion temperatures. The use of these theoretical data in engine operation and in the evaluation of experimental data is described.

  1. Effects of animal activity and air temperature on methane and ammonia emissions from a naturally ventilated building for dairy cows

    NASA Astrophysics Data System (ADS)

    Ngwabie, N. M.; Jeppsson, K.-H.; Gustafsson, G.; Nimmermark, S.

    2011-12-01

    Knowledge of how different factors affect gas emissions from animal buildings can be useful for emission prediction purposes and for the improvement of emission abatement techniques. In this study, the effects of dairy cow activity and indoor air temperature on gas emissions were examined. The concentrations of CH 4, NH 3, CO 2 and N 2O inside and outside a dairy cow building were measured continuously between February and May together with animal activity and air temperature. The building was naturally ventilated and had a solid concrete floor which sloped towards a central urine gutter. Manure was scraped from the floor once every hour in the daytime and once every second hour at night into a partly covered indoor pit which was emptied daily at 6 a.m. and at 5 p.m. Gas emissions were calculated from the measured gas concentrations and ventilation rates estimated by the CO 2 balance method. The animal activity and emission rates of CH 4 and NH 3 showed significant diurnal variations with two peaks which were probably related to the feeding routine. On an average day, CH 4 emissions ranged from 7 to 15 g LU -1 h -1 and NH 3 emissions ranged from 0.4 to 1.5 g LU -1 h -1 (1 LU = 500 kg animal weight). Mean emissions of CH 4 and NH 3 were 10.8 g LU -1 h -1 and 0.81 g LU -1 h -1, respectively. The NH 3 emissions were comparable to emissions from tied stall buildings and represented a 4% loss in manure nitrogen. At moderate levels, temperature seems to affect the behaviour of dairy cows and in this study where the daily indoor air temperature ranged from about 5 up to about 20 °C, the daily activity of the cows decreased with increasing indoor air temperature ( r = -0.78). Results suggest that enteric fermentation is the main source of CH 4 emissions from systems of the type in this study, while NH 3 is mainly emitted from the manure. Daily CH 4 emissions increased significantly with the activity of the cows ( r = 0.61) while daily NH 3 emissions increased

  2. Meteorology (Temperature)

    Atmospheric Science Data Center

    2014-09-25

    Air Temperature (° C)   Daily Temperature Range (° C) Difference between the average daily maximum ... The monthly accumulation of degrees when the daily mean temperature is above 18° C.   Heating Degree Days below 18° C ...

  3. Using Machine learning method to estimate Air Temperature from MODIS over Berlin

    NASA Astrophysics Data System (ADS)

    Marzban, F.; Preusker, R.; Sodoudi, S.; Taheri, H.; Allahbakhshi, M.

    2015-12-01

    Land Surface Temperature (LST) is defined as the temperature of the interface between the Earth's surface and its atmosphere and thus it is a critical variable to understand land-atmosphere interactions and a key parameter in meteorological and hydrological studies, which is involved in energy fluxes. Air temperature (Tair) is one of the most important input variables in different spatially distributed hydrological, ecological models. The estimation of near surface air temperature is useful for a wide range of applications. Some applications from traffic or energy management, require Tair data in high spatial and temporal resolution at two meters height above the ground (T2m), sometimes in near-real-time. Thus, a parameterization based on boundary layer physical principles was developed that determines the air temperature from remote sensing data (MODIS). Tair is commonly obtained from synoptic measurements in weather stations. However, the derivation of near surface air temperature from the LST derived from satellite is far from straight forward. T2m is not driven directly by the sun, but indirectly by LST, thus T2m can be parameterized from the LST and other variables such as Albedo, NDVI, Water vapor and etc. Most of the previous studies have focused on estimating T2m based on simple and advanced statistical approaches, Temperature-Vegetation index and energy-balance approaches but the main objective of this research is to explore the relationships between T2m and LST in Berlin by using Artificial intelligence method with the aim of studying key variables to allow us establishing suitable techniques to obtain Tair from satellite Products and ground data. Secondly, an attempt was explored to identify an individual mix of attributes that reveals a particular pattern to better understanding variation of T2m during day and nighttime over the different area of Berlin. For this reason, a three layer Feedforward neural networks is considered with LMA algorithm

  4. CMOS Amperometric ADC With High Sensitivity, Dynamic Range and Power Efficiency for Air Quality Monitoring.

    PubMed

    Li, Haitao; Boling, C Sam; Mason, Andrew J

    2016-08-01

    Airborne pollutants are a leading cause of illness and mortality globally. Electrochemical gas sensors show great promise for personal air quality monitoring to address this worldwide health crisis. However, implementing miniaturized arrays of such sensors demands high performance instrumentation circuits that simultaneously meet challenging power, area, sensitivity, noise and dynamic range goals. This paper presents a new multi-channel CMOS amperometric ADC featuring pixel-level architecture for gas sensor arrays. The circuit combines digital modulation of input currents and an incremental Σ∆ ADC to achieve wide dynamic range and high sensitivity with very high power efficiency and compact size. Fabricated in 0.5 [Formula: see text] CMOS, the circuit was measured to have 164 dB cross-scale dynamic range, 100 fA sensitivity while consuming only 241 [Formula: see text] and 0.157 [Formula: see text] active area per channel. Electrochemical experiments with liquid and gas targets demonstrate the circuit's real-time response to a wide range of analyte concentrations.

  5. Tonopah Test Range Air Monitoring: CY2015 Meteorological, Radiological, and Airborne Particulate Observations

    SciTech Connect

    Nikolich, George; Shadel, Craig; Chapman, Jenny; McCurdy, Greg; Etyemezian, Vicken; Miller, Julianne J.; Mizell, Steve

    2016-09-01

    In 1963, the U.S. Department of Energy (DOE) (formerly the Atomic Energy Commission [AEC]), implemented Operation Roller Coaster on the Tonopah Test Range (TTR) and an adjacent area of the Nevada Test and Training Range (NTTR) (formerly the Nellis Air Force Range). The operation resulted in radionuclide-contaminated soils at the Clean Slate I, II, and III sites. This report documents observations made during ongoing monitoring of radiological, meteorological, and dust conditions at stations installed adjacent to Clean Slate I and Clean Slate III, and at the TTR Sandia National Laboratories (SNL) Range Operations Control (ROC) center. The primary objective of the monitoring effort is to determine if winds blowing across the Clean Slate sites are transporting particles of radionuclide-contaminated soil beyond the physical and administrative boundaries of the sites. Radionuclide assessment of airborne particulates in 2015 found the gross alpha and gross beta values of dust collected from the filters at the monitoring stations are consistent with background conditions. The meteorological and particle monitoring indicate that conditions for wind-borne contaminant movement exist at the Clean Slate sites and that, although the transport of radionuclide-contaminated soil by suspension has not been detected, movement by saltation is occurring.

  6. Short-term effects of air temperature on plasma metabolite concentrations in patients undergoing cardiac cattheterization.

    EPA Science Inventory

    BACKGROUND: Epidemiological studies have shown associations between air temperature and cardiovascular health outcomes. Metabolic dysregulation might also play a role in the development of cardiovascular disease.OBJECTIVES: To investigate short-term temperature effects on metabol...

  7. Associations of day-to-day temperature change and diurnal temperature range with out-of-hospital cardiac arrest.

    PubMed

    Onozuka, Daisuke; Hagihara, Akihito

    2017-01-01

    Background Although the impacts of temperature on mortality and morbidity have been documented, few studies have investigated whether day-to-day temperature change and diurnal temperature range (DTR) are independent risk factors for out-of-hospital cardiac arrest (OHCA). Design This was a prospective, population-based, observational study. Methods We obtained all OHCA data from 2005-2013 from six major prefectures in Japan: Hokkaido, Tokyo, Kanagawa, Aichi, Kyoto, and Osaka. We used a quasi-Poisson regression analysis with a distributed-lag non-linear model to assess the associations of day-to-day temperature change and DTR with OHCA for each prefecture. Results In total, 271,698 OHCAs of presumed cardiac origin were reported during the study period. There was a significant increase in the risk of OHCA associated with cold temperature in five prefectures, with relative risks (RRs) ranging from 1.298 (95% confidence interval (CI) 1.022-1.649) in Hokkaido to 3.893 (95% CI 1.713-8.845) in Kyoto. DTR was adversely associated with OHCA on hot days in Aichi (RR 1.158; 95% CI 1.028-1.304) and on cold days in Tokyo (RR 1.030; 95% CI 1.000-1.060), Kanagawa (RR 1.042; 95% CI 1.005-1.082), Kyoto (RR 1.060; 95% CI 1.001-1.122), and Osaka (RR 1.050; 95% CI 1.014-1.088), whereas there was no significant association between day-to-day temperature change and OHCA. Conclusion We found that associations between day-to-day temperature change and DTR and OHCA were generally small compared with the association with mean temperature. Our findings suggest that preventative measures for temperature-related OHCA may be more effective when focused on mean temperature and DTR.

  8. Stream air temperature relations to classify stream ground water interactions in a karst setting, central Pennsylvania, USA

    NASA Astrophysics Data System (ADS)

    O'Driscoll, Michael A.; DeWalle, David R.

    2006-09-01

    SummaryStream-ground water interactions in karst vary from complete losses through swallow holes, to reemergences from springs. Our study objective was to compare stream-air temperature and energy exchange relationships across various stream-ground water relationships in a carbonate watershed. It was hypothesized that ground water-fed stream segments could be distinguished from perched/losing segments using stream-air temperature relationships. Two types of computations were conducted: (1) comparisons of stream-air temperature relationships for the period of October 1999-September 2002 at 12 sites in the Spring Creek drainage and (2) detailed energy budget computations for the same period for ground water-dominated Thompson Run and Lower Buffalo Run, a stream with negligible ground water inputs. Weekly average air temperatures and stream temperatures were highly correlated, but slopes and intercepts of the relationship varied for the 12 sites. Slopes ranged from 0.19 to 0.67 and intercepts ranged from 3.23 to 9.07 °C. A two-component mixing model with end members of ground water and actual stream temperatures indicated that the slope and intercept of the stream-air temperature relationship was controlled by ground water inputs. Streams with large ground water inputs had greater intercepts and lesser slopes than streams that were seasonally losing, perched, and/or distant from ground water inputs. Energy fluxes across the air-water interface were greatest for the ground water-fed stream due to increased longwave, latent, and sensible heat losses from the stream in winter when large temperature and vapor pressure differences existed between the stream and air. Advection of ground water was an important source and sink for heat in the ground water-fed stream, depending on season. In contrast, along the seasonally losing stream reach, advection was of minimal importance and stream temperatures were dominated by energy exchange across the air- water interface. Overall

  9. Brain and arterial blood temperatures of free-ranging oryx ( Oryx gazella).

    PubMed

    Maloney, Shane K; Fuller, Andrea; Mitchell, Graham; Mitchell, Duncan

    2002-01-01

    We used implanted miniature data loggers to measure brain and arterial blood temperatures every 5 min for up to 15 days in four free-ranging oryx ( Oryx gazella) in their natural habitat. Globe temperatures exceeded 45 degrees C and average peak radiant heat load was 800 W.m(-2). Arterial blood temperature exhibited a moderate amplitude nychthemeral rhythm of 1.8+/-0.3 degrees C (mean +/-SD). The amplitude of the nychthemeral rhythm was not influenced by variations in ambient heat load. Average brain temperature exceeded carotid arterial blood temperature by 0.29 degrees C but there was a range of body temperatures over which the brain could be up to 0.4 degrees C cooler or 0.5 degrees C warmer than arterial blood. At high body temperatures (>39.5 degrees C) at rest, three of the animals tended to maintain the brain cooler than arterial blood. During exercise the brain was always warmer than arterial blood. The slope of the regression line relating brain temperature to carotid blood temperature was less than one. At short time scales of 5-20 min, brain temperature varied significantly more than did carotid blood temperature. We attribute part of the variability in brain temperature to transient stress responses and the influence of sympathetic activation attenuating selective brain cooling. We conclude that, contrary to the widely cited postulate, the carotid rete does not protect the brain during hyperthermia. Oryx also do not show adaptive heterothermy and, over short time intervals, have a brain temperature more variable than carotid blood temperature.

  10. Rainfall Prediction using Soil and Air Temperature in a Tropical Station

    NASA Astrophysics Data System (ADS)

    Chacko, Tessy P.; Renuka, G.

    2007-07-01

    An attempt is made to establish a linkage between soil and air temperature and south-west monsoon rainfall at Pillicode (12°12'N,75°10'E) a tropical station in north Kerala. The dependence of monsoon rainfall on pre-monsoon soil temperature decreases as the depth of the soil increases. A regression equation has been developed for the estimation of monsoon rainfall using pre-monsoon soil and air temperature. The results show that sub soil temperature along with air temperature can be used for forecasting the monsoon level.

  11. AirSTAR Hardware and Software Design for Beyond Visual Range Flight Research

    NASA Technical Reports Server (NTRS)

    Laughter, Sean; Cox, David

    2016-01-01

    The National Aeronautics and Space Administration (NASA) Airborne Subscale Transport Aircraft Research (AirSTAR) Unmanned Aerial System (UAS) is a facility developed to study the flight dynamics of vehicles in emergency conditions, in support of aviation safety research. The system was upgraded to have its operational range significantly expanded, going beyond the line of sight of a ground-based pilot. A redesign of the airborne flight hardware was undertaken, as well as significant changes to the software base, in order to provide appropriate autonomous behavior in response to a number of potential failures and hazards. Ground hardware and system monitors were also upgraded to include redundant communication links, including ADS-B based position displays and an independent flight termination system. The design included both custom and commercially available avionics, combined to allow flexibility in flight experiment design while still benefiting from tested configurations in reversionary flight modes. A similar hierarchy was employed in the software architecture, to allow research codes to be tested, with a fallback to more thoroughly validated flight controls. As a remotely piloted facility, ground systems were also developed to ensure the flight modes and system state were communicated to ground operations personnel in real-time. Presented in this paper is a general overview of the concept of operations for beyond visual range flight, and a detailed review of the airborne hardware and software design. This discussion is held in the context of the safety and procedural requirements that drove many of the design decisions for the AirSTAR UAS Beyond Visual Range capability.

  12. Electrolytes for Use in High Energy Lithium-Ion Batteries with Wide Operating Temperature Range

    NASA Technical Reports Server (NTRS)

    Smart, Marshall C.; Ratnakumar, B. V.; West, W. C.; Whitcanack, L. D.; Huang, C.; Soler, J.; Krause, F. C.

    2011-01-01

    Objectives of this work are: (1) Develop advanced Li -ion electrolytes that enable cell operation over a wide temperature range (i.e., -30 to +60C). (2) Improve the high temperature stability and lifetime characteristics of wide operating temperature electrolytes. (3) Improve the high voltage stability of these candidate electrolytes systems to enable operation up to 5V with high specific energy cathode materials. (4) Define the performance limitations at low and high temperature extremes, as well as, life limiting processes. (5) Demonstrate the performance of advanced electrolytes in large capacity prototype cells.

  13. 40 CFR 1065.670 - NOX intake-air humidity and temperature corrections.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.670 NOX intake-air humidity and temperature corrections. See the standard-setting part to determine if you... 40 Protection of Environment 34 2013-07-01 2013-07-01 false NOX intake-air humidity...

  14. 40 CFR 1065.670 - NOX intake-air humidity and temperature corrections.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.670 NOX intake-air humidity and temperature corrections. See the standard-setting part to determine if you... 40 Protection of Environment 32 2010-07-01 2010-07-01 false NOX intake-air humidity...

  15. 40 CFR 1065.670 - NOX intake-air humidity and temperature corrections.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.670 NOX intake-air humidity and temperature corrections. See the standard-setting part to determine if you... 40 Protection of Environment 33 2014-07-01 2014-07-01 false NOX intake-air humidity...

  16. 40 CFR 1065.670 - NOX intake-air humidity and temperature corrections.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.670 NOX intake-air humidity and temperature corrections. See the standard-setting part to determine if you... 40 Protection of Environment 33 2011-07-01 2011-07-01 false NOX intake-air humidity...

  17. 40 CFR 1065.670 - NOX intake-air humidity and temperature corrections.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.670 NOX intake-air humidity and temperature corrections. See the standard-setting part to determine if you... 40 Protection of Environment 34 2012-07-01 2012-07-01 false NOX intake-air humidity...

  18. One-Component Pressure-Temperature Phase Diagrams in the Presence of Air

    ERIC Educational Resources Information Center

    Andrade-Gamboa, Julio; Martire, Daniel O.; Donati, Edgardo R.

    2010-01-01

    One-component phase diagrams are good approximations to predict pressure-temperature ("P-T") behavior of a substance in the presence of air, provided air pressure is not much higher than the vapor pressure. However, at any air pressure, and from the conceptual point of view, the use of a traditional "P-T" phase diagram is not strictly correct. In…

  19. Dual fluorescence sensor for trace oxygen and temperature with unmatched range and sensitivity.

    PubMed

    Baleizão, Carlos; Nagl, Stefan; Schäferling, Michael; Berberan-Santos, Mário N; Wolfbeis, Otto S

    2008-08-15

    An optical dual sensor for oxygen and temperature is presented that is highly oxygen sensitive and covers a broad temperature range. Dual sensing is based on luminescence lifetime measurements. The novel sensor contains two luminescent compounds incorporated into polymer films. The temperature-sensitive dye (ruthenium tris-1,10-phenanthroline) has a highly temperature-dependent luminescence and is incorporated in poly(acrylonitrile) to avoid cross-sensitivity to oxygen. Fullerene C70 was used as the oxygen-sensitive probe owing to its strong thermally activated delayed fluorescence at elevated temperatures that is extremely oxygen sensitive. The cross-sensitivity of C70 to temperature is accounted for by means of the temperature sensor. C70 is incorporated into a highly oxygen-permeable polymer, either ethyl cellulose or organosilica. The two luminescent probes have different emission spectra and decay times, and their emissions can be discriminated using both parameters. Spatially resolved sensing is achieved by means of fluorescence lifetime imaging. The response times of the sensor to oxygen are short. The dual sensor exhibits a temperature operation range between at least 0 and 120 degrees C, and detection limits for oxygen in the ppbv range, operating for oxygen concentrations up to at least 50 ppmv. These ranges outperform all dual oxygen and temperature sensors reported so far. The dual sensor presented in this study is especially appropriate for measurements under extreme conditions such as high temperatures and ultralow oxygen levels. This dual sensor is a key step forward in a number of scientifically or commercially important applications including food packaging, for monitoring of hyperthermophilic microorganisms, in space technology, and safety and security applications in terms of detection of oxygen leaks.

  20. Observations of acyl peroxy nitrates during the front range air pollution and photochemistry experiment (FRAPPE)

    NASA Astrophysics Data System (ADS)

    Zaragoza, Jake

    The Colorado Front Range is an ozone (O3) nonattainment region. The photochemistry of the region is influenced by emissions from the urban and oil and gas sectors, the complex terrain, and the meteorology. The Front Range Air Pollution and Photochemistry Experiment (FRAPPE) was a field intensive carried out in the Colorado Front Range during summer 2014 to characterize the regional chemical environment. Acyl peroxy nitrates (PANs) play important roles in atmospheric chemistry, acting as either sinks or sources for nitrogen oxides (NOx) depending on conditions. PANs and other trace gas species were measured at the Boulder Atmospheric Observatory (BAO) during FRAPPE. Situated at the southwestern edge of the Denver-Julesburg Basin and 35 km north of Denver, BAO has been the site of multiple field studies aiming to characterize the influence of emissions from the oil and gas sector. Here we focus on an analysis of the PANs measurements from BAO during FRAPPE. In particular, we focus on peroxyacetic nitric anhydride (PAN, CH3C(O)O2NO2), peroxymethacrylic nitric anhydride (MPAN, CH2C(CH3)C(O)O2NO2) and peroxypropionic nitric anhydride (PPN, CH3CH2C(O)O 2NO2). Mean and maximum PAN mixing ratios (5-minute point) were 275 and 1519 pptv respectively. There were four days during FRAPPE where the observed PAN abundance exceeded 1 ppbv. These days were examined using FLEXible PARTicle dispersion model (FLEXPART) back trajectories in order to determine air mass origin. The high PAN days occurred when air masses were recirculating in the region, often under Denver Cyclones. However, a visual inspection of FLEXPART trajectories throughout FRAPPE showed that recirculation events in the region occurred on days with high (>1 ppbv), moderate (500 pptv - 1 ppbv), and low (<500 pptv) afternoon PAN mixing ratios. The PPN/PAN ratio observed at the BAO tower during the summer of 2014 was 21%, which suggests anthropogenically enhanced photochemical activity. The ratio was very consistent (R

  1. Startup of air-cooled condensers and dry cooling towers at low temperatures of the cooling air

    NASA Astrophysics Data System (ADS)

    Milman, O. O.; Ptakhin, A. V.; Kondratev, A. V.; Shifrin, B. A.; Yankov, G. G.

    2016-05-01

    The problems of startup and performance of air-cooled condensers (ACC) and dry cooling towers (DCT) at low cooling air temperatures are considered. Effects of the startup of the ACC at sub-zero temperatures are described. Different options of the ACC heating up are analyzed, and examples of existing technologies are presented (electric heating, heating up with hot air or steam, and internal and external heating). The use of additional heat exchanging sections, steam tracers, in the DCT design is described. The need for high power in cases of electric heating and heating up with hot air is noted. An experimental stand for research and testing of the ACC startup at low temperatures is described. The design of the three-pass ACC unit is given, and its advantages over classical single-pass design at low temperatures are listed. The formation of ice plugs inside the heat exchanging tubes during the start-up of ACC and DCT at low cooling air temperatures is analyzed. Experimental data on the effect of the steam flow rate, steam nozzle distance from the heat-exchange surface, and their orientation in space on the metal temperature were collected, and test results are analyzed. It is noted that the surface temperature at the end of the heat up is almost independent from its initial temperature. Recommendations for the safe start-up of ACCs and DCTs are given. The heating flow necessary to sufficiently heat up heat-exchange surfaces of ACCs and DCTs for the safe startup is estimated. The technology and the process of the heat up of the ACC with the heating steam external supply are described by the example of the startup of the full-scale section of the ACC at sub-zero temperatures of the cooling air, and the advantages of the proposed start-up technology are confirmed.

  2. Measurement of effective temperature range of fire service thermal imaging cameras

    NASA Astrophysics Data System (ADS)

    Amon, Francine; Bryner, Nelson

    2008-04-01

    The use of thermal imaging cameras (TIC) by the fire service is increasing as fire fighters become more aware of the value of these tools. The National Fire Protection Association (NFPA) is currently developing a consensus standard for design and performance requirements of TIC as used by the fire service. The National Institute of Standards and Technology facilitates this process by providing recommendations for science-based performance metrics and test methods to the NFPA technical committee charged with the development of this standard. A suite of imaging performance metrics and test methods, based on the harsh operating environment and limitations of use particular to the fire service, has been proposed for inclusion in the standard. The Effective Temperature Range (ETR) measures the range of temperatures that a TIC can view while still providing useful information to the user. Specifically, extreme heat in the field of view tends to inhibit a TIC's ability to discern surfaces having intermediate temperatures, such as victims and fire fighters. The ETR measures the contrast of a target having alternating 25 °C and 30 °C bars while an increasing temperature range is imposed on other surfaces in the field of view. The ETR also indicates the thermal conditions that trigger a shift in integration time common to TIC employing microbolometer sensors. The reported values for this imaging performance metric are the hot surface temperature range within which the TIC provides adequate bar contrast, and the hot surface temperature at which the TIC shifts integration time.

  3. Effects of Outside Air Temperature on Movement of Phosphine Gas in Concrete Elevator Bins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies that measured the movement and concentration of phosphine gas in upright concrete bins over time indicated that fumigant movement was dictated by air currents, which in turn, were a function of the difference between the average grain temperature and the average outside air temperature durin...

  4. Predicting seed cotton moisture content from changes in drying air temperature - second year

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A mathematical model was used to predict seed cotton moisture content in the overhead section of a cotton gin. The model took into account the temperature, mass flow, and specific heat of both the air and seed cotton. Air temperatures and mass flows were measured for a second year at a commercial g...

  5. Temperature modifies the association between particulate air pollution and mortality: A multi-city study in South Korea.

    PubMed

    Kim, Satbyul Estella; Lim, Youn-Hee; Kim, Ho

    2015-08-15

    Substantial epidemiologic literature has demonstrated the effects of air pollution and temperature on mortality. However, there is inconsistent evidence regarding the temperature modification effect on acute mortality due to air pollution. Herein, we investigated the effects of temperature on the relationship between air pollution and mortality due to non-accidental, cardiovascular, and respiratory death in seven cities in South Korea. We applied stratified time-series models to the data sets in order to examine whether the effects of particulate matter <10 μm (PM10) on mortality were modified by temperature. The effect of PM10 on daily mortality was first quantified within different ranges of temperatures at each location using a time-series model, and then the estimates were pooled through a random-effects meta-analysis using the maximum likelihood method. From all the data sets, 828,787 non-accidental deaths were registered from 2000-2009. The highest overall risk between PM10 and non-accidental or cardiovascular mortality was observed on extremely hot days (daily mean temperature: >99th percentile) in individuals aged <65 years. In those aged ≥65 years, the highest overall risk between PM10 and non-accidental or cardiovascular mortality was observed on very hot days and not on extremely hot days (daily mean temperature: 95-99th percentile). There were strong harmful effects from PM10 on non-accidental mortality with the highest temperature range (>99th percentile) in men, with a very high temperature range (95-99th percentile) in women. Our findings showed that temperature can affect the relationship between the PM10 levels and cause-specific mortality. Moreover, the differences were apparent after considering the age and sex groups.

  6. The design of an air-cooled metallic high temperature radial turbine

    NASA Technical Reports Server (NTRS)

    Snyder, Philip H.; Roelke, Richard J.

    1988-01-01

    Recent trends in small advanced gas turbine engines call for higher turbine inlet temperatures. Advances in radial turbine technology have opened the way for a cooled metallic radial turbine capable of withstanding turbine inlet temperatures of 2500 F while meeting the challenge of high efficiency in this small flow size range. In response to this need, a small air-cooled radial turbine has been designed utilizing internal blade coolant passages. The coolant flow passage design is uniquely tailored to simultaneously meet rotor cooling needs and rotor fabrication constraints. The rotor flow-path design seeks to realize improved aerodynamic blade loading characteristics and high efficiency while satisfying rotor life requirements. An up-scaled version of the final engine rotor is currently under fabrication and, after instrumentation, will be tested in the warm turbine test facility at the NASA Lewis Research Center.

  7. Increasing sea surface temperature and range shifts of intertidal gastropods along the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Rubal, Marcos; Veiga, Puri; Cacabelos, Eva; Moreira, Juan; Sousa-Pinto, Isabel

    2013-03-01

    There are well-documented changes in abundance and geographical range of intertidal invertebrates related to climate change at north Europe. However, the effect of sea surface warming on intertidal invertebrates has been poorly studied at lower latitudes. Here we analyze potential changes in the abundance patterns and distribution range of rocky intertidal gastropods related to climate change along the Iberian Peninsula. To achieve this aim, the spatial distribution and range of sub-tropical, warm- and cold-water species of intertidal gastropods was explored by a fully hierarchical sampling design considering four different spatial scales, i.e. from region (100 s of km apart) to quadrats (ms apart). Variability on their patterns of abundance was explored by analysis of variance, changes on their distribution ranges were detected by comparing with previous records and their relationship with sea water temperature was explored by rank correlation analyses. Mean values of sea surface temperature along the Iberian coast, between 1949 and 2010, were obtained from in situ data compiled for three different grid squares: south Portugal, north Portugal, and Galicia. Lusitanian species did not show significant correlation with sea water temperature or changes on their distributional range or abundance, along the temperature gradient considered. The sub-tropical species Siphonaria pectinata has, however, increased its distribution range while boreal cold-water species showed the opposite pattern. The latter was more evident for Littorina littorea that was almost absent from the studied rocky shores of the Iberian Peninsula. Sub-tropical and boreal species showed significant but opposite correlation with sea water temperature. We hypothesized that the energetic cost of frequent exposures to sub-lethal temperatures might be responsible for these shifts. Therefore, intertidal gastropods at the Atlantic Iberian Peninsula coast are responding to the effect of global warming as it

  8. Prediction of air temperature in the aircraft cabin under different operational conditions

    NASA Astrophysics Data System (ADS)

    Volavý, F.; Fišer, J.; Nöske, I.

    2013-04-01

    This paper deals with the prediction of the air temperature in the aircraft cabin by means of Computational Fluid Dynamics. The simulations are performed on the CFD model which is based on geometry and cabin interior arrangement of the Flight Test Facility (FTF) located at Fraunhofer IBP, Germany. The experimental test flights under three different cabin temperatures were done in FTF and the various data were gathered during these flights. Air temperature in the cabin was measured on probes located near feet, torso and head of each passenger and also surface temperature and air temperature distributed from inlets were measured. The data were firstly analysed in order to obtain boundary conditions for cabin surfaces and inlets. Then the results of air temperature from the simulations were compared with measured data. The suitability and accuracy of the CFD approach for temperature prediction is discussed.

  9. Seasonal variation of air temperature at the Mendel Station, James Ross Island in the period of 2006-2009

    NASA Astrophysics Data System (ADS)

    Laska, Kamil; Prošek, Pavel; Budík, Ladislav

    2010-05-01

    Key words: air temperature, seasonal variation, James Ross Island, Antarctic Peninsula Recently, significant role of the atmospheric and oceanic circulation variation on positive trend of near surface air temperature along the Antarctic Peninsula has been reported by many authors. However, small number of the permanent meteorological stations located on the Peninsula coast embarrasses a detail analysis. It comprises analysis of spatiotemporal variability of climatic conditions and validation of regional atmospheric climate models. However, geographical location of the Czech Johann Gregor Mendel Station (hereafter Mendel Station) newly established on the northern ice-free part of the James Ross Island provides an opportunity to fill the gap. There are recorded important meteorological characteristics which allow to evaluate specific climatic regime of the region and their impact on the ice-shelf disintegration and glacier retreat. Mendel Station (63°48'S, 57°53'W) is located on marine terrace at the altitude of 7 m. In 2006, a monitoring network of several automatic weather stations was installed at different altitudes ranging from the seashore level up to mesas and tops of glaciers (514 m a.s.l.). In this contribution, a seasonal variation of near surface air temperature at the Mendel Station in the period of 2006-2009 is presented. Annual mean air temperature was -7.2 °C. Seasonal mean temperature ranged from +1.4 °C (December-February) to -17.7 °C (June-August). Frequently, the highest temperature occurred in the second half of January. It reached maximum of +8.1 °C. Sudden changes of atmospheric circulation pattern during winter caused a large interdiurnal variability of air temperature with the amplitude of 30 °C.

  10. System and method for air temperature control in an oxygen transport membrane based reactor

    DOEpatents

    Kelly, Sean M

    2016-09-27

    A system and method for air temperature control in an oxygen transport membrane based reactor is provided. The system and method involves introducing a specific quantity of cooling air or trim air in between stages in a multistage oxygen transport membrane based reactor or furnace to maintain generally consistent surface temperatures of the oxygen transport membrane elements and associated reactors. The associated reactors may include reforming reactors, boilers or process gas heaters.

  11. Metabolic response to air temperature and wind in day-old mallards and a standard operative temperature scale.

    PubMed

    Bakken, G S; Reynolds, P S; Kenow, K P; Korschgen, C E; Boysen, A F

    1999-01-01

    Most duckling mortality occurs during the week following hatching and is often associated with cold, windy, wet weather and scattering of the brood. We estimated the thermoregulatory demands imposed by cold, windy weather on isolated 1-d-old mallard (Anas platyrhynchos) ducklings resting in cover. We measured O2 consumption and evaporative water loss at air temperatures from 5 degrees to 25 degrees C and wind speeds of 0.1, 0.2, 0.5, and 1.0 m/s. Metabolic heat production increased as wind increased or temperature decreased but was less sensitive to wind than that of either adult passerines or small mammals. Evaporative heat loss ranged from 5% to 17% of heat production. Evaporative heat loss and the ratio of evaporative heat loss to metabolic heat production was significantly lower in rest phase. These data were used to define a standard operative temperature (Tes) scale for night or heavy overcast conditions. An increase of wind speed from 0.1 to 1 m/s decreased Tes by 3 degrees -5 degrees C.

  12. Metabolic response to air temperature and wind in day-old mallards and a standard operative temperature scale

    USGS Publications Warehouse

    Bakken, G.S.; Reynolds, P.S.; Kenow, K.P.; Korschgen, C.E.; Boysen, A.F.

    1999-01-01

    Most duckling mortality occurs during the week following hatching and is often associated with cold, windy, wet weather and scattering of the brood. We estimated the thermoregulatory demands imposed by cold, windy weather on isolated 1-d-old mallard (Anas platyrhynchos) ducklings resting in cover. We measured O-2 consumption and evaporative water loss at air temperatures from 5 degrees to 25 degrees C and wind speeds of 0.1, 0.2, 0.5, and 1.0 mis. Metabolic heat production increased as wind increased or temperature decreased but was less sensitive to wind than that of either adult passerines or small mammals. Evaporative heat loss ranged from 5% to 17% of heat production. Evaporative heal loss and the ratio of evaporative heat loss to metabolic heat production was significantly lower in rest phase. These data were used to define a standard operative temperature (T-es) scale for night or heavy overcast conditions. An increase of wind speed from 0.1 to 1 mis decreased T-es by 3 degrees-5 degrees C.

  13. Analysis of the Dryden Wet Bulb GLobe Temperature Algorithm for White Sands Missile Range

    NASA Technical Reports Server (NTRS)

    LaQuay, Ryan Matthew

    2011-01-01

    In locations where workforce is exposed to high relative humidity and light winds, heat stress is a significant concern. Such is the case at the White Sands Missile Range in New Mexico. Heat stress is depicted by the wet bulb globe temperature, which is the official measurement used by the American Conference of Governmental Industrial Hygienists. The wet bulb globe temperature is measured by an instrument which was designed to be portable and needing routine maintenance. As an alternative form for measuring the wet bulb globe temperature, algorithms have been created to calculate the wet bulb globe temperature from basic meteorological observations. The algorithms are location dependent; therefore a specific algorithm is usually not suitable for multiple locations. Due to climatology similarities, the algorithm developed for use at the Dryden Flight Research Center was applied to data from the White Sands Missile Range. A study was performed that compared a wet bulb globe instrument to data from two Surface Atmospheric Measurement Systems that was applied to the Dryden wet bulb globe temperature algorithm. The period of study was from June to September of2009, with focus being applied from 0900 to 1800, local time. Analysis showed that the algorithm worked well, with a few exceptions. The algorithm becomes less accurate to the measurement when the dew point temperature is over 10 Celsius. Cloud cover also has a significant effect on the measured wet bulb globe temperature. The algorithm does not show red and black heat stress flags well due to shorter time scales of such events. The results of this study show that it is plausible that the Dryden Flight Research wet bulb globe temperature algorithm is compatible with the White Sands Missile Range, except for when there are increased dew point temperatures and cloud cover or precipitation. During such occasions, the wet bulb globe temperature instrument would be the preferred method of measurement. Out of the 30

  14. Air temperature "singularities" as a tool for the comprehension of the climate diversity in Europe

    NASA Astrophysics Data System (ADS)

    Jarzyna, Krzysztof

    2014-05-01

    Air temperature "singularities" were used to study climate diversity in Europe. The basis of analysis were data of mean daily air temperature for 50-years period (1951-2000) from 66 European meteorological stations. Multiyear mean air temperature values were counted for the each day of the year at first (29th February was omitted). Next a theoretical sine curve of annual air temperature course was created with help of the Fourier's analysis for the each station. Differences between theoretical and observed mean vales of daily air temperatures were counted in the next step. The biggest of these differences (below the lower quartile and above the upper quartile) lasting at least 3 days can be treated as thermal "singularities". A cluster analysis was used to find similarities of the singularities occurrence in analyzed stations. As a result 8 clusters were distinguished representing regions with different thermal "singularities" occurrence pattern.

  15. Detonation cell size measurements in high-temperature hydrogen-air-steam mixtures at the BNL high-temperature combustion facility

    SciTech Connect

    Ciccarelli, G.; Ginsberg, T.; Boccio, J.L.

    1997-11-01

    The High-Temperature Combustion Facility (HTCF) was designed and constructed with the objective of studying detonation phenomena in mixtures of hydrogen-air-steam at initially high temperatures. The central element of the HTCF is a 27-cm inner-diameter, 21.3-m long cylindrical test vessel capable of being heating to 700K {+-} 14K. A unique feature of the HTCF is the {open_quotes}diaphragmless{close_quotes} acetylene-oxygen gas driver which is used to initiate the detonation in the test gas. Cell size measurements have shown that for any hydrogen-air-steam mixture, increasing the initial mixture temperature, in the range of 300K to 650K, while maintaining the initial pressure of 0.1 MPa, decreases the cell size and thus makes the mixture more detonable. The effect of steam dilution on cell size was tested in stoichiometric and off-stoichiometric (e.g., equivalence ratio of 0.5) hydrogen-air mixtures. Increasing the steam dilution in hydrogen-air mixtures at 0.1 MPa initial pressure increases the cell size, irrespective of initial temperature. It is also observed that the desensitizing effect of steam diminished with increased initial temperature. A 1-dimensional, steady-state Zel`dovich, von Neumann, Doring (ZND) model, with full chemical kinetics, has been used to predict cell size for hydrogen-air-steam mixtures at different initial conditions. Qualitatively the model predicts the overall trends observed in the measured cell size versus mixture composition and initial temperature and pressure. It was found that the proportionality constant used to predict detonation cell size from the calculated ZND model reaction zone varies between 10 and 100 depending on the mixture composition and initial temperature. 32 refs., 35 figs.

  16. Measurements of average heat-transfer and friction coefficients for subsonic flow of air in smooth tubes at high surface and fluid temperatures

    NASA Technical Reports Server (NTRS)

    Humble, Leroy V; Lowdermilk, Warren H; Desmon, Leland G

    1951-01-01

    An investigation of forced-convection heat transfer and associated pressure drops was conducted with air flowing through smooth tubes for an over-all range of surface temperature from 535 degrees to 3050 degrees r, inlet-air temperature from 535 degrees to 1500 degrees r, Reynolds number up to 500,000, exit Mach number up to 1, heat flux up to 150,000 btu per hour per square foot, length-diameter ratio from 30 to 120, and three entrance configurations. Most of the data are for heat addition to the air; a few results are included for cooling of the air. The over-all range of surface-to-air temperature ratio was from 0.46 to 3.5.

  17. Modeling subcanopy incoming longwave radiation to seasonal snow using air and tree trunk temperatures

    NASA Astrophysics Data System (ADS)

    Webster, Clare; Rutter, Nick; Zahner, Franziska; Jonas, Tobias

    2016-02-01

    Data collected at three Swiss alpine forested sites over a combined 11 year period were used to evaluate the role of air temperature in modeling subcanopy incoming longwave radiation to the snow surface. Simulated subcanopy incoming longwave radiation is traditionally partitioned into that from the sky and that from the canopy, i.e., a two-part model. Initial uncertainties in predicting longwave radiation using the two-part model resulted from vertical differences in measured air temperature. Above-canopy (35 m) air temperatures were higher than those within (10 m) and below (2 m) canopy throughout four snow seasons (December-April), demonstrating how the forest canopy can act as a cold sink for air. Lowest model root-mean-square error (RMSE) was using above-canopy air temperature. Further investigation of modeling subcanopy longwave radiation using above-canopy air temperature showed underestimations, particularly during periods of high insolation. In order to explicitly account for canopy temperatures in modeling longwave radiation, the two-part model was improved by incorporating a measured trunk view component and trunk temperature. Trunk temperature measurements were up to 25°C higher than locally measured air temperatures. This three-part model reduced the RMSE by up to 7.7 W m-2 from the two-part air temperature model at all sensor positions across the 2014 snowmelt season and performed particularly well during periods of high insolation when errors from the two-part model were up to 40 W m-2. A parameterization predicting tree trunk temperatures using measured air temperature and incoming shortwave radiation demonstrate a simple method that can be applied to provide input to the three-part model across midlatitude coniferous forests.

  18. Electrolytes for Use in High Energy Lithium-ion Batteries with Wide Operating Temperature Range

    NASA Technical Reports Server (NTRS)

    Smart, Marshall C.; Ratnakumar, B. V.; West, W. C.; Whitcanack, L. D.; Huang, C.; Soler, J.; Krause, F. C.

    2012-01-01

    Met programmatic milestones for program. Demonstrated improved performance with wide operating temperature electrolytes containing ester co-solvents (i.e., methyl butyrate) containing electrolyte additives in A123 prototype cells: Previously demonstrated excellent low temperature performance, including 11C rates at -30 C and the ability to perform well down to -60 C. Excellent cycle life at room temperature has been displayed, with over 5,000 cycles being demonstrated. Good high temperature cycle life performance has also been achieved. Demonstrated improved performance with methyl propionate-containing electrolytes in large capacity prototype cells: Demonstrated the wide operating temperature range capability in large cells (12 Ah), successfully scaling up technology from 0.25 Ah size cells. Demonstrated improved performance at low temperature and good cycle life at 40 C with methyl propionate-based electrolyte containing increasing FEC content and the use of LiBOB as an additive. Utilized three-electrode cells to investigate the electrochemical characteristics of high voltage systems coupled with wide operating temperature range electrolytes: From Tafel polarization measurements on each electrode, it is evident the NMC-based cathode displays poor lithium kinetics (being the limiting electrode). The MB-based formulations containing LiBOB delivered the best rate capability at low temperature, which is attributed to improved cathode kinetics. Whereas, the use of lithium oxalate as an additive lead to the highest reversible capacity and lower irreversible losses.

  19. Impact of Surface Air Temperature and Snow Cover Depth on the Upper Soil Temperature Variations in Russia

    NASA Astrophysics Data System (ADS)

    Sherstyukov, A. B.; Sherstyukov, B. G.; Groisman, P. Y.

    2007-12-01

    A study of the impact of climate changes during for the last four decades on soil temperatures at depths up to 3.2 meters has been conducted for the territory of Russia. For the 1965-2004 period, we compiled and analyzed data from all Russian meteorological stations with long-term soil temperature observations at depths 80, 160 and 320 cm. Traditionally, these stations also observe a complete set of standard meteorological variables (that include surface air temperature and extensive monitoring of snow cover characteristics). This allowed us to investigate the impact of surface air temperatures and snow depth variations on soil temperatures in the upper soil layer, to quantify it using statistical analyses of multi-dimensional 40-year-long time series at 164 locations throughout the country, and assess the representativeness of the obtained results. Three-dimensional spatial distributions of regression and correlation coefficients were mapped for warm and cold seasons separately as well as for the entire year, and thereafter analyzed. In the permafrost zone we found special features in these fields that distinctively separate the permafrost zone from the remaining territory. In this zone, soil temperatures are practically uncorrelated with surface air temperatures and variations of the snow depth controls soil temperature variations (with R2 up to 0.5) Quantitative estimates of the contribution of mid-annual air temperature and snow cover depth in the long-term changes of mid-annual soil temperatures across the Russia territory were received. We found that the prevailing influence on soil temperature variations in the European part was surface air temperatures and in the Asian part of Russia was snow cover depth. Furthermore, increase of the winter snow depth in the permafrost zone (by preserving the heat accumulated in the warm season) promotes annual soil temperature increase and therefore may foster the further permafrost degradation associated with ongoing

  20. Broadening of mesophase temperature range induced by doping calamitic mesogen with banana-shaped mesogen

    NASA Astrophysics Data System (ADS)

    Cvetinov, Miroslav; Stojanović, Maja; Obadović, Dušanka; Vajda, Aniko; Fodor-Csorba, Katalin; Eber, Nandor

    2016-03-01

    We have investigated three binary mixtures composed of selected banana-shaped dopant in low concentrations and calamitic mesogen in high. Banana-shaped dopant forms a B7 phase, while the calamitic mesogen exhibit nematic and smectic SmA and SmC phases. The occurring mesophases have been identified by their optical textures. At dopant concentrations of 2.2 and 3.1 mol%, there is evident broadening of nematic and smectic SmA temperature ranges in respect to the pure calamitic compound. Yet, the mixture with dopant concentration of 7 mol% exhibits narrower temperature ranges of mesophases. Increasing dopant concentration caused lowering of all phase transitions temperatures (TI-N, TN-SmA, TSmA-SmC) in all investigated mixtures. Therefore, mixing classic calamitic compounds with novel banana-shaped compound in low concentrations is viable way to attain useful mesophase range for application in industry.

  1. Implications of the corneal temperature range in the prediction of laser thermal damage. [Monkeys

    SciTech Connect

    Mikesell, G.W. Jr.; Schepler, K.L.

    1980-04-01

    Corneal temperatures of the rhesus monkeys have been measured under conditions that may exist during laser experiments. The minimum and maximum temperatures found for all experimental conditions were 29.54/sup 0/C and 39.16/sup 0/C, respectively, a range of 9.62/sup 0/C. A computer model of thermal damage due to laser irradiation was used to determine the effect varying initial temperature could have on corneal damage thresholds (ED50's). The range of 9.62/sup 0/C found in monkeys for all experimental conditions corresponded to a 39% difference in threshold power. The dependence of damage thresholds on initial temperature could be an important factor to consider when basing laser safety standards on damage threshold data.

  2. Estimating the Urban Bias of Surface Shelter Temperatures Using Upper-Air and Satellite Data

    NASA Astrophysics Data System (ADS)

    Epperson, David Lee

    An alternative method is presented for estimating the urban bias of surface shelter temperatures due to the effect of the urban heat island Multivariate regression techniques were utilized to predict surface shelter temperatures for the time period 1986-89 using upper-air data from the European Centre for Medium-Range Weather Forecasting (ECMWF) to represent the background climate, site-specific data to represent the local landscape, and satellite-derived data--the Normalized Difference Vegetation Index (NDVI) and the Defense Meteorological Satellite Program (DMSP) nighttime brightness data--to represent the urban landscape. Models for the United States (US) were developed for mean monthly maximum, mean, and minimum temperatures using data from over 1000 stations in the US Co-operative (COOP) Network and over 1150 stations in the Global Historical Climate Network (GHCN, mean temperatures only). Urban biases for the US and for individual stations were calculated and compared with the results of other research. The urban bias of US temperatures, as derived from all US stations (urban and rural) used in the models, averaged near 0.40 ^circC for minimum temperatures, near 0.25^circC for mean temperatures, and near 0.10^circC for maximum temperatures. On an annual basis, the urban biases of minimum temperatures for individual stations ranged from near -1.1^circC for rural stations to 2.4^circC for stations from the largest urban areas. The urban bias of US mean temperatures in this study (0.25^ circC) was shown to be larger than the US (0.05-0.15^circC) and global (0.01-0.10^circC) urban biases from other studies, where the confidence in the estimated urban biases was less. Thus, there is a need to assess the urban bias that is present in the global temperature record using the methodology presented in this study. The results of this study indicate minimal problems for global application, once the global NDVI and DMSP data become available, as opposed to other studies

  3. [Hazard assessment of the impact of high temperature and air pollution on public health in Moscow].

    PubMed

    Revich, B A; Shaposhnikov, D A; Avaliani, S L; Rubinshtein, K G; Emelina, S V; Shiriaev, M V; Semutnikova, E G; Zakharova, P V; Kislova, O Iu

    2015-01-01

    In the article there are considered the main problems of assessing public health risks of the combined effects of high temperatures and air pollution with the account taken of the consequences of abnormally hot weather observed in summer 2010 in Moscow and without equals in the history of meteorological measurements in the city. The daily average concentrations of fine suspended particles matter (PM10) in the city during peatland fires from 4 to 9 August are emphasized to be within the range of 431-906 μ/m3, being 7.2-15.1 times the Russian maximum permissible concentration (MPCs) (60 μ/m3). The anomalous heat and high levels of air pollution in this period were shown to cause a significant increase in excess mortality among the population of Moscow. There was established the relative gain in mortality from all natural causes per 10 μg/m3 increase in daily average concentrations of PM10 and ozone, which was respectively: 0.47% (95%; CI: 0.31-0.63) and 0.41% (95%; CI: 0.31-1.13). On the base of the statistical analysis of daily mortality rates, meteorological indices, the concentrations of PM10 and ozone there was developed marking scale for the risk assessment of these indices accordingly to 4 gradings--low (permissible), warning, alert, and a hazard level. There has been substantiated the importance of the introduction of the system for the early alert for hazard weather events and the unified rating scale for the hazard of high air temperatures and high levels of air pollution with PM10 and ozone, which allows to take timely measures for the protection of the public health.

  4. Tonopah Test Range Air Monitoring. CY2014 Meteorological, Radiological, and Airborne Particulate Observations

    SciTech Connect

    Nikoloch, George; Shadel, Craig; Chapman, Jenny; Mizell, Steve A.; McCurdy, Greg; Etyemezian, Vicken; Miller, Julianne J.

    2015-10-01

    In 1963, the U.S. Department of Energy (DOE) (formerly the Atomic Energy Commission [AEC]), implemented Operation Roller Coaster on the Tonopah Test Range (TTR) and an adjacent area of the Nevada Test and Training Range (NTTR) (formerly the Nellis Air Force Range). This test resulted in radionuclide-contaminated soils at Clean Slate I, II, and III. This report documents observations made during ongoing monitoring of radiological, meteorological, and dust conditions at stations installed adjacent to Clean Slate I and Clean Slate III and at the TTR Range Operations Control center. The primary objective of the monitoring effort is to determine if winds blowing across the Clean Slate sites are transporting particles of radionuclide-contaminated soils beyond both the physical and administrative boundaries of the sites. Results for the calendar year (CY) 2014 monitoring are: (1) the gross alpha and gross beta values from the monitoring stations are approximately equivalent to the highest values observed during the CY2014 reporting at the surrounding Community Environmental Monitoring Program (CEMP) stations; (2) only naturally occurring radionuclides were identified in the gamma spectral analyses; (3) the ambient gamma radiation measurements indicate that the average annual gamma exposure is similar at all three monitoring stations and periodic intervals of increased gamma values appear to be associated with storm fronts passing through the area; and (4) the concentrations of both resuspended dust and saltated sand particles generally increase with increasing wind speed. Differences in the observed dust concentrations are likely the result of differences in the soil characteristics immediately adjacent to the monitoring stations. Neither the resuspended particulate radiological analyses nor the ambient gamma radiation measurements suggest wind transport of radionuclide-contaminated soils.

  5. Tonopah Test Range Air Monitoring: CY2013 Meteorological, Radiological, and Airborne Particulate Observations

    SciTech Connect

    Mizell, Steve A; Nikolich, George; Shadel, Craig; McCurdy, Greg; Etyemezian, Vicken; Miller, Julianne J

    2014-10-01

    In 1963, the U.S. Department of Energy (DOE) (formerly the Atomic Energy Commission [AEC]), implemented Operation Roller Coaster on the Tonopah Test Range (TTR) and an adjacent area of the Nevada Test and Training Range (NTTR) (formerly the Nellis Air Force Range). This test resulted in radionuclide-contaminated soils at Clean Slate I, II, and III. This report documents observations made during on-going monitoring of radiological, meteorological, and dust conditions at stations installed adjacent to Clean Slate I and Clean Slate III and at the TTR Range Operations Control center. The primary objective of the monitoring effort is to determine if winds blowing across the Clean Slate sites are transporting particles of radionuclide-contaminated soils beyond both the physical and administrative boundaries of the sites. Results for the calendar year (CY) 2013 monitoring include: (1) the gross alpha and gross beta values from the monitoring stations are approximately equivalent to the highest values observed during the CY2012 reporting at the surrounding Community Environmental Monitoring Program (CEMP) stations (this was the latest documented data available at the time of this writing); (2) only naturally occurring radionuclides were identified in the gamma spectral analyses; (3) the ambient gamma radiation measurements indicate that the average annual gamma exposure is similar at all three monitoring stations and periodic intervals of increased gamma values appear to be associated with storm fronts passing through the area; and (4) the concentrations of both resuspended dust and saltated sand particles generally increase with increasing wind speed. However, differences in the observed dust concentrations are likely due to differences in the soil characteristics immediately adjacent to the monitoring stations. Neither the resuspended particulate radiological analyses nor the ambient gamma radiation measurements suggest wind transport of radionuclide-contaminated soils.

  6. Surprises from quenches in long-range-interacting systems: temperature inversion and cooling

    NASA Astrophysics Data System (ADS)

    Gupta, Shamik; Casetti, Lapo

    2016-10-01

    What happens when one of the parameters governing the dynamics of a long-range interacting system of particles in thermal equilibrium is abruptly changed (quenched) to a different value? While a short-range system, under the same conditions, will relax in time to a new thermal equilibrium with a uniform temperature across the system, a long-range system shows a fast relaxation to a non-equilibrium quasistationary state (QSS). The lifetime of such an off-equilibrium state diverges with the system size, and the temperature is non-uniform across the system. Quite surprisingly, the density profile in the QSS obtained after the quench is anticorrelated with the temperature profile in space, thus exhibiting the phenomenon of temperature inversion: denser regions are colder than sparser ones. We illustrate with extensive molecular dynamics simulations the ubiquity of this scenario in a prototypical long-range interacting system subject to a variety of quenching protocols, and in a model that mimics an experimental setup of atoms interacting with light in an optical cavity. We further demonstrate how a procedure of iterative quenching combined with filtering out the high-energy particles in the system may be employed to cool the system. Temperature inversion is observed in nature in some astrophysical settings; our results imply that such a phenomenon should be observable, and could even be exploitable to advantage, also in controlled laboratory experiments.

  7. Complexity analysis of the air temperature and the precipitation time series in Serbia

    NASA Astrophysics Data System (ADS)

    Mimić, G.; Mihailović, D. T.; Kapor, D.

    2017-02-01

    In this paper, we have analyzed the time series of daily values for three meteorological elements, two continuous and a discontinuous one, i.e., the maximum and minimum air temperature and the precipitation. The analysis was done based on the observations from seven stations in Serbia from the period 1951-2010. The main aim of this paper was to quantify the complexity of the annual values for the mentioned time series and to calculate the rate of its change. For that purpose, we have used the sample entropy and the Kolmogorov complexity as the measures which can indicate the variability and irregularity of a given time series. Results obtained show that the maximum temperature has increasing trends in the given period which points out a warming, ranged in the interval 1-2 °C. The increasing temperature indicates the higher internal energy of the atmosphere, changing the weather patterns, manifested in the time series. The Kolmogorov complexity of the maximum temperature time series has statistically significant increasing trends, while the sample entropy has increasing but statistically insignificant trend. The trends of complexity measures for the minimum temperature depend on the location. Both complexity measures for the precipitation time series have decreasing trends.

  8. OXIDATION OF INCONEL 718 IN AIR AT TEMPERATURES FROM 973K TO 1620K.

    SciTech Connect

    GREENE,G.A.; FINFROCK,C.C.

    2000-10-01

    As part of the APT project, it was necessary to quantify the release of tungsten from the APT spallation target during postulated accident conditions in order to develop accident source terms for accident consequence characterization. Experiments with tungsten rods at high temperatures in a flowing steam environment characteristic of postulated accidents revealed that considerable vaporization of the tungsten occurred as a result of reactions with the steam and that the aerosols which formed were readily transported away from the tungsten surfaces, thus exposing fresh tungsten to react with more steam. The resulting tungsten release fractions and source terms were undesirable and it was decided to clad the tungsten target with Inconel 718 in order to protect it from contact with steam during an accident and mitigate the accident source term and the consequences. As part of the material selection criteria, experiments were conducted with Inconel 718 at high temperatures to evaluate the rate of oxidation of the proposed clad material over as wide a temperature range as possible, as well as to determine the high-temperature failure limit of the material. Samples of Inconel 718 were inserted into a preheated furnace at temperatures ranging from 973 K to 1620 K and oxidized in air for varying periods of time. After oxidizing in air at a constant temperature for the prescribed time and then being allowed to cool, the samples would be reweighed to determine their weight gain due to the uptake of oxygen. From these weight gain measurements, it was possible to identify three regimes of oxidation for Inconel 718: a low-temperature regime in which the samples became passivated after the initial oxidation, an intermediate-temperature regime in which the rate of oxidation was limited by diffusion and exhibited a constant parabolic rate dependence, and a high-temperature regime in which material deformation and damage accompanied an accelerated oxidation rate above the parabolic

  9. Uncertainties of satellite-derived surface skin temperatures in the polar oceans: MODIS, AIRS/AMSU, and AIRS only

    NASA Astrophysics Data System (ADS)

    Kang, H.-J.; Yoo, J.-M.; Jeong, M.-J.; Won, Y.-I.

    2015-05-01

    Uncertainties in the satellite-derived Surface Skin Temperature (SST) data in the polar oceans during two periods (16-24 April and 15-23 September) of 2003-2014 were investigated and the three datasets were intercompared as follows: MODerate Resolution Imaging Spectroradiometer Ice Surface Temperature (MODIS IST), the SST of the Atmospheric Infrared Sounder/Advanced Microwave Sounding Unit-A (AIRS/AMSU), and AIRS only. AIRS only algorithm was developed in preparation for the degradation of the AMSU-A. MODIS IST was systematically up to 1.65 K warmer at the sea ice boundary and up to 2.04 K colder in the polar sea ice regions of both the Arctic and Antarctic than that of the AIRS/AMSU. This difference in the results could have been caused by the surface classification method. The spatial correlation coefficient of the AIRS only to the AIRS/AMSU (0.992-0.999) method was greater than that of the MODIS IST to the AIRS/AMSU (0.968-0.994). The SST of the AIRS only compared to that of the AIRS/AMSU had a bias of 0.168 K with a RMSE of 0.590 K over the Northern Hemisphere high latitudes and a bias of -0.109 K with a RMSE of 0.852 K over the Southern Hemisphere high latitudes. There was a systematic disagreement between the AIRS retrievals at the boundary of the sea ice, because the AIRS only algorithm utilized a~less accurate GCM forecast over the seasonally-varying frozen oceans than the microwave data. The three datasets (MODIS, AIRS/AMSU and AIRS only) showed significant warming rates (2.3 ± 1.7 ~2.8 ± 1.9 K decade-1) in the northern high latitude regions (70-80° N) as expected from the ice-albedo feedback. The systematic temperature disagreement associated with surface type classification had an impact on the resulting temperature trends.

  10. Uncertainties of satellite-derived surface skin temperatures in the polar oceans: MODIS, AIRS/AMSU, and AIRS only

    NASA Astrophysics Data System (ADS)

    Kang, H.-J.; Yoo, J.-M.; Jeong, M.-J.; Won, Y.-I.

    2015-10-01

    Uncertainties in the satellite-derived surface skin temperature (SST) data in the polar oceans during two periods (16-24 April and 15-23 September) 2003-2014 were investigated and the three data sets were intercompared as follows: MODerate Resolution Imaging Spectroradiometer Ice Surface Temperature (MODIS IST), the SST of the Atmospheric Infrared Sounder/Advanced Microwave Sounding Unit-A (AIRS/AMSU), and AIRS only. The AIRS only algorithm was developed in preparation for the degradation of the AMSU-A. MODIS IST was systematically warmer up to 1.65 K at the sea ice boundary and colder down to -2.04 K in the polar sea ice regions of both the Arctic and Antarctic than that of the AIRS/AMSU. This difference in the results could have been caused by the surface classification method. The spatial correlation coefficient of the AIRS only to the AIRS/AMSU (0.992-0.999) method was greater than that of the MODIS IST to the AIRS/AMSU (0.968-0.994). The SST of the AIRS only compared to that of the AIRS/AMSU had a bias of 0.168 K with a RMSE of 0.590 K over the Northern Hemisphere high latitudes and a bias of -0.109 K with a RMSE of 0.852 K over the Southern Hemisphere high latitudes. There was a systematic disagreement between the AIRS retrievals at the boundary of the sea ice, because the AIRS only algorithm utilized a less accurate GCM forecast over the seasonally varying frozen oceans than the microwave data. The three data sets (MODIS, AIRS/AMSU and AIRS only) showed significant warming rates (2.3 ± 1.7 ~ 2.8 ± 1.9 K decade-1) in the northern high regions (70-80° N) as expected from the ice-albedo feedback. The systematic temperature disagreement associated with surface type classification had an impact on the resulting temperature trends.

  11. Temperature Range Shifts for Three European Tree Species over the Last 10,000 Years

    PubMed Central

    Cheddadi, Rachid; Araújo, Miguel B.; Maiorano, Luigi; Edwards, Mary; Guisan, Antoine; Carré, Matthieu; Chevalier, Manuel; Pearman, Peter B.

    2016-01-01

    We quantified the degree to which the relationship between the geographic distribution of three major European tree species, Abies alba, Fagus sylvatica and Picea abies and January temperature (Tjan) has remained stable over the past 10,000 years. We used an extended data-set of fossil pollen records over Europe to reconstruct spatial variation in Tjan values for each 1000-year time slice between 10,000 and 3000 years BP (before present). We evaluated the relationships between the occurrences of the three species at each time slice and the spatially interpolated Tjan values, and compared these to their modern temperature ranges. Our results reveal that F. sylvatica and P. abies experienced Tjan ranges during the Holocene that differ from those of the present, while A. alba occurred over a Tjan range that is comparable to its modern one. Our data suggest the need for re-evaluation of the assumption of stable climate tolerances at a scale of several thousand years. The temperature range instability in our observed data independently validates similar results based exclusively on modeled Holocene temperatures. Our study complements previous studies that used modeled data by identifying variation in frequencies of occurrence of populations within the limits of suitable climate. However, substantial changes that were observed in the realized thermal niches over the Holocene tend to suggest that predicting future species distributions should not solely be based on modern realized niches, and needs to account for the past variation in the climate variables that drive species ranges. PMID:27826308

  12. Atomic oxygen recombination on the ODS PM 1000 at high temperature under air plasma

    NASA Astrophysics Data System (ADS)

    Balat-Pichelin, M.; Bêche, E.

    2010-06-01

    High temperature materials are necessary for the design of primary heat shields for future reusable space vehicles re-entering atmospheric planet at hypersonic velocity. During the re-entry phase on earth, one of the most important phenomena occurring on the heat shield is the recombination of atomic oxygen and this phenomenon is more or less catalyzed by the material of the heat shield. PM 1000 is planned to be use on the EXPERT capsule to study in real conditions its catalycity. Before the flight, it is necessary to perform measurements on ground test facility. Experimental data of the recombination coefficient of atomic oxygen under air plasma flow were obtained in the diffusion reactor MESOX on pre-oxidized PM 1000, for two total pressures 300 and 1000 Pa in the temperature range (850-1650 K) using actinometry and optical emission spectroscopy. In this investigation, the evolution of the recombination coefficient is dependent of temperature, pressure level and also of the chemical composition of the surface leading to one order of magnitude for a given temperature. The recombination coefficient is increasing with temperature and also dependent on the static pressure. The surface change due to the plasma exposure is inspected with SEM, XRD and XPS. As chromium oxide is the main part of the oxide layer formed during the oxidation in air plasma conditions, a sintered Cr 2O 3 sample was elaborated from powders to compare the data of the recombination coefficient obtained on PM 1000. Pre- and post-test analyses on the several materials were carried out using SEM, WDS, XRD and XPS.

  13. Micromechanical properties of C70 single crystals in the temperature range 77-350 K

    NASA Astrophysics Data System (ADS)

    Lubenets, S. V.; Natsik, V. D.; Fomenko, L. S.; Rusakova, A. V.; Osipyan, Yu. A.; Orlov, V. I.; Sidorov, N. S.; Izotov, A. N.

    2012-03-01

    Hexagonal single crystals of C70 down to 1-2 mm in size were grown, which allowed the investigation of their low-temperature mechanical properties for the first time. Morphology, microplasticity anisotropy, and the temperature dependence of Vickers microhardness HV (T) of the C70 crystals involving all known phase transitions were studied with the aid of optical microscopy and microindentation in the temperature range 77-350 K. The association of the features of HV (T) dependence with orientation phase transformations was analyzed. It is suggested that microplasticity anisotropy of the C70 crystals correlates with the active slip systems.

  14. A miniaturized piezoelectric turbine with self-regulation for increased air speed range

    SciTech Connect

    Fu, Hailing Yeatman, Eric M.

    2015-12-14

    This paper presents the design and demonstration of a piezoelectric turbine with self-regulation for increased air speed range. The turbine's transduction is achieved by magnetic “plucking” of a piezoelectric beam by the passing rotor. The increased speed range is achieved by the self-regulating mechanism which can dynamically adjust the magnetic coupling between the magnets on the turbine rotor and the piezoelectric beam using a micro-spring. The spring is controlled passively by the centrifugal force of the magnet on the rotor. This mechanism automatically changes the relative position of the magnets at different rotational speeds, making the coupling weak at low airflow speeds and strong at high speeds. Hence, the device can start up with a low airflow speed, and the output power can be ensured when the airflow speed is high. A theoretical model was established to analyse the turbine's performance, advantages, and to optimize its design parameters. A prototype was fabricated and tested in a wind tunnel. The start-up airflow speed was 2.34 m/s, showing a 30% improvement against a harvester without the mechanism.

  15. A miniaturized piezoelectric turbine with self-regulation for increased air speed range

    NASA Astrophysics Data System (ADS)

    Fu, Hailing; Yeatman, Eric M.

    2015-12-01

    This paper presents the design and demonstration of a piezoelectric turbine with self-regulation for increased air speed range. The turbine's transduction is achieved by magnetic "plucking" of a piezoelectric beam by the passing rotor. The increased speed range is achieved by the self-regulating mechanism which can dynamically adjust the magnetic coupling between the magnets on the turbine rotor and the piezoelectric beam using a micro-spring. The spring is controlled passively by the centrifugal force of the magnet on the rotor. This mechanism automatically changes the relative position of the magnets at different rotational speeds, making the coupling weak at low airflow speeds and strong at high speeds. Hence, the device can start up with a low airflow speed, and the output power can be ensured when the airflow speed is high. A theoretical model was established to analyse the turbine's performance, advantages, and to optimize its design parameters. A prototype was fabricated and tested in a wind tunnel. The start-up airflow speed was 2.34 m/s, showing a 30% improvement against a harvester without the mechanism.

  16. High Temperature Extends the Range of Size Discrimination of Nonionic Polymers by a Biological Nanopore

    PubMed Central

    Piguet, Fabien; Ouldali, Hadjer; Discala, Françoise; Breton, Marie-France; Behrends, Jan C.; Pelta, Juan; Oukhaled, Abdelghani

    2016-01-01

    We explore the effect of temperature on the interaction of polydisperse mixtures of nonionic poly(ethylene glycol) (PEG) polymers of different average molar masses with the biological nanopore α-hemolysin. In contrast with what has been previously observed with various nanopores and analytes, we find that, for PEGs larger than a threshold molar mass (2000 g/mol, PEG 2000), increasing temperature increases the duration of the PEG/nanopore interaction. In the case of PEG 3400 the duration increases by up to a factor of 100 when the temperature increases from 5 °C to 45 °C. Importantly, we find that increasing temperature extends the polymer size range of application of nanopore-based single-molecule mass spectrometry (Np-SMMS)-type size discrimination. Indeed, in the case of PEG 3400, discrimination of individual molecular species of different monomer number is impossible at room temperature but is achieved when the temperature is raised to 45 °C. We interpret our observations as the consequence of a decrease of PEG solubility and a collapse of PEG molecules with higher temperatures. In addition to expanding the range of application of Np-SMMS to larger nonionic polymers, our findings highlight the crucial role of the polymer solubility for the nanopore detection. PMID:27924860

  17. High Temperature Extends the Range of Size Discrimination of Nonionic Polymers by a Biological Nanopore

    NASA Astrophysics Data System (ADS)

    Piguet, Fabien; Ouldali, Hadjer; Discala, Françoise; Breton, Marie-France; Behrends, Jan C.; Pelta, Juan; Oukhaled, Abdelghani

    2016-12-01

    We explore the effect of temperature on the interaction of polydisperse mixtures of nonionic poly(ethylene glycol) (PEG) polymers of different average molar masses with the biological nanopore α-hemolysin. In contrast with what has been previously observed with various nanopores and analytes, we find that, for PEGs larger than a threshold molar mass (2000 g/mol, PEG 2000), increasing temperature increases the duration of the PEG/nanopore interaction. In the case of PEG 3400 the duration increases by up to a factor of 100 when the temperature increases from 5 °C to 45 °C. Importantly, we find that increasing temperature extends the polymer size range of application of nanopore-based single-molecule mass spectrometry (Np-SMMS)-type size discrimination. Indeed, in the case of PEG 3400, discrimination of individual molecular species of different monomer number is impossible at room temperature but is achieved when the temperature is raised to 45 °C. We interpret our observations as the consequence of a decrease of PEG solubility and a collapse of PEG molecules with higher temperatures. In addition to expanding the range of application of Np-SMMS to larger nonionic polymers, our findings highlight the crucial role of the polymer solubility for the nanopore detection.

  18. Comparison of AIRS and IASI Surface Observations of DomeC in Antarctica with Surface Temperatures Reported by AWS8989

    NASA Astrophysics Data System (ADS)

    Elliott, D. A.; Aumann, H. H.

    2008-12-01

    The decrease of the ice in the Antarctic indicates that the land and the ocean along the coastline are warming up. Representative numbers for warming at the surface further inland are much more complicated due to the vast size of the continent. The Automated Weather Station AWS8989 has been reporting temperatures from Concordia Station on DomeC in Antarctica every 10 minutes since 1996. AWS8989 is located about 1 mile from the power plant at Concordia Station. We compare the surface temperatures at DomeC deduced from Atmospheric Infrared Sounder (AIRS) and Infrared Atmospheric Sounding Interferometer (IASI) data to the surface temperature reported by Automated Weather Station AWS8989 for the year between May 1, 2007 and April 30, 2008. AIRS and IASI measure the mean skin brightness temperature in a 50-km-radius circle from DomeC, while the AWS reports the temperature of the air at 3 meters above the surface. The AIRS and IASI measurements agree within 50 mK over the entire temperature range from 190 K in the winter to 245 K in the summer, but consistently report a colder temperature than the AWS8989. The warm bias of AWS8989 is season dependent, changing from 1.5 K warm in the winter to 5.5 K warm in the summer. Comparison of AIRS data in 2005 with a temporary Italian AWS (Aumann et al. 2006) and located several miles upwind from the power station, showed no significant temperature bias throughout the year 2005. The warm readings of AWS8989 are likely due the combination of a season-independent 1.5 K warm calibration bias in the AWS8989 sensor plus thermal contamination of the AWS8989 site. This heat island effect ranges from near zero during the low-activity winter months to about 4 K during the summer months with the highest activity at Concordia Station. The fact that activities at DomeC are increasing makes surface temperature trends from AWS8989 suspect. AIRS and IASI are hyperspectral infrared sounders designed in support of weather forecasting and climate

  19. Rapid poleward range expansion of tropical reef corals in response to rising sea surface temperatures

    NASA Astrophysics Data System (ADS)

    Yamano, Hiroya; Sugihara, Kaoru; Nomura, Keiichi

    2011-02-01

    Rising temperatures caused by climatic warming may cause poleward range shifts and/or expansions in species distribution. Tropical reef corals (hereafter corals) are some of the world's most important species, being not only primary producers, but also habitat-forming species, and thus fundamental ecosystem modification is expected according to changes in their distribution. Although most studies of climate change effects on corals have focused on temperature-induced coral bleaching in tropical areas, poleward range shifts and/or expansions may also occur in temperate areas. We show the first large-scale evidence of the poleward range expansion of modern corals, based on 80 years of national records from the temperate areas of Japan, where century-long measurements of in situ sea-surface temperatures have shown statistically significant rises. Four major coral species categories, including two key species for reef formation in tropical areas, showed poleward range expansions since the 1930s, whereas no species demonstrated southward range shrinkage or local extinction. The speed of these expansions reached up to 14 km/year, which is far greater than that for other species. Our results, in combination with recent findings suggesting range expansions of tropical coral-reef associated organisms, strongly suggest that rapid, fundamental modifications of temperate coastal ecosystems could be in progress.

  20. A comparison of urban heat islands mapped using skin temperature, air temperature, and apparent temperature (Humidex), for the greater Vancouver area.

    PubMed

    Ho, Hung Chak; Knudby, Anders; Xu, Yongming; Hodul, Matus; Aminipouri, Mehdi

    2016-02-15

    Apparent temperature is more closely related to mortality during extreme heat events than other temperature variables, yet spatial epidemiology studies typically use skin temperature (also known as land surface temperature) to quantify heat exposure because it is relatively easy to map from satellite data. An empirical approach to map apparent temperature at the neighborhood scale, which relies on publicly available weather station observations and spatial data layers combined in a random forest regression model, was demonstrated for greater Vancouver, Canada. Model errors were acceptable (cross-validated RMSE=2.04 °C) and the resulting map of apparent temperature, calibrated for a typical hot summer day, corresponded well with past temperature research in the area. A comparison with field measurements as well as similar maps of skin temperature and air temperature revealed that skin temperature was poorly correlated with both air temperature (R(2)=0.38) and apparent temperature (R(2)=0.39). While the latter two were more similar (R(2)=0.87), apparent temperature was predicted to exceed air temperature by more than 5 °C in several urban areas as well as around the confluence of the Pitt and Fraser rivers. We conclude that skin temperature is not a suitable proxy for human heat exposure, and that spatial epidemiology studies could benefit from mapping apparent temperature, using an approach similar to the one reported here, to better quantify differences in heat exposure that exist across an urban landscape.

  1. Creep performance of oxide ceramic fiber materials at elevated temperature in air and in steam

    NASA Astrophysics Data System (ADS)

    Armani, Clinton J.

    Structural aerospace components that operate in severe conditions, such as extreme temperatures and detrimental environments, require structural materials that have superior long-term mechanical properties and that are thermochemically stable over a broad range of service temperatures and environments. Ceramic matrix composites (CMCs) capable of excellent mechanical performance in harsh environments are prime candidates for such applications. Oxide ceramic materials have been used as constituents in CMCs. However, recent studies have shown that high-temperature mechanical performance of oxide-oxide CMCs deteriorate in a steam-rich environment. The degradation of strength at elevated temperature in steam has been attributed to the environmentally assisted subcritical crack growth in the oxide fibers. Furthermore, oxide-oxide CMCs have shown significant increases in steady-state creep rates in steam. The present research investigated the effects of steam on the high-temperature creep and monotonic tension performance of several oxide ceramic materials. Experimental facilities were designed and configured, and experimental methods were developed to explore the influence of steam on the mechanical behaviors of ceramic fiber tows and of ceramic bulk materials under temperatures in the 1100--1300°C range. The effects of steam on creep behavior of Nextel(TM)610 and Nextel(TM)720 fiber tows were examined. Creep rates at elevated temperatures in air and in steam were obtained for both types of fibers. Relationships between creep rates and applied stresses were modeled and underlying creep mechanisms were identified. For both types of fiber tows, a creep life prediction analysis was performed using linear elastic fracture mechanics and a power-law crack velocity model. These results have not been previously reported and have critical design implications for CMC components operating in steam or near the recommended design limits. Predictions were assessed and validated via

  2. High temperature range recuperator. Phase II. Prototype demonstration and material and analytical studies. Final report

    SciTech Connect

    1980-04-01

    A summary of the work performed to fully evaluate the commercial potential of a unique ceramic recuperator for use in recovering waste heat from high temperature furnace exhaust gases is presented. The recuperator concept being developed consists of a vertical cylindrical heat exchange column formed from modular sections. Within the column, the gasketed modules form two helical flow passages - one for high temperature exhaust gases and one for pre-heating combustion air. The column is operated in a counterflow mode, with the exhaust gas entering at the bottom and the combustion air entering at the top of the column. Activities included design and procurement of prototype recuperator modules, construction and testing of two prototype recuperator assemblies, exposure and mechanical properties testing of candidate materials, structural analysis of the modules, and assessment of the economic viability of the concept. The results of the project indicated that the proposed recuperator concept was feasible from a technical standpoint. Economic analysis based upon recuperator performance characteristics and module manufacturing costs defined during the program indicated that 3 to 10 years (depending upon pre-heat temperature) would be required to recover the capital cost of the system in combustion air preheat applications. At this stage in the development of the recuperator, many factors in the analysis had to be assumed. Significant changes in some of the assumptions could dramatically affect the economics. For example, utilizing $2.85 per mcf for the natural gas price (as opposed to $2.00 per mcf) could reduce the payback period by more than half in certain cases. In addition, future commercial application will depend upon ceramic component manufacturing technique advances and cost reduction.

  3. The EUSTACE project: delivering global, daily information on surface air temperature

    NASA Astrophysics Data System (ADS)

    Morice, C. P.; Rayner, N. A.; Auchmann, R.; Bessembinder, J.; Bronnimann, S.; Brugnara, Y.; Conway, E. A.; Ghent, D.; Good, E.; Herring, K.; Kennedy, J.; Lindgren, F.; Madsen, K. S.; Merchant, C. J.; van der Schrier, G.; Stephens, A.; Tonboe, R. T.; Waterfall, A. M.; Mitchelson, J.; Woolway, I.

    2015-12-01

    Day-to-day variations in surface air temperature affect society in many ways; however, daily surface air temperature measurements are not available everywhere. A global daily analysis cannot be achieved with measurements made in situ alone, so incorporation of satellite retrievals is needed. To achieve this, we must develop an understanding of the relationships between traditional (land and marine) surface air temperature measurements and retrievals of surface skin temperature from satellite measurements, i.e. Land Surface Temperature, Ice Surface Temperature, Sea Surface Temperature and Lake Surface Water Temperature. These relationships can be derived either empirically or with the help of a physical model.Here we discuss the science needed to produce a fully-global daily analysis (or ensemble of analyses) of surface air temperature on the centennial scale, integrating different ground-based and satellite-borne data types. Information contained in the satellite retrievals would be used to create globally-complete fields in the past, using statistical models of how surface air temperature varies in a connected way from place to place. As the data volumes involved are considerable, such work needs to include development of new "Big Data" analysis methods.We will present plans and progress along this road in the EUSTACE project (2015-June 2018), i.e.: • providing new, consistent, multi-component estimates of uncertainty in surface skin temperature retrievals from satellites; • identifying inhomogeneities in daily surface air temperature measurement series from weather stations and correcting for these over Europe; • estimating surface air temperature over all surfaces of Earth from surface skin temperature retrievals; • using new statistical techniques to provide information on higher spatial and temporal scales than currently available, making optimum use of information in data-rich eras.Information will also be given on how interested users can become

  4. Use of remotely sensed land surface temperature as a proxy for air temperatures at high elevations: Findings from a 5000 m elevational transect across Kilimanjaro

    NASA Astrophysics Data System (ADS)

    Pepin, N. C.; Maeda, E. E.; Williams, R.

    2016-09-01

    High elevations are thought to be warming more rapidly than lower elevations, but there is a lack of air temperature observations in high mountains. This study compares instantaneous values of land surface temperature (10:30/22:30 and 01:30/13:30 local solar time) as measured by Moderate Resolution Imaging Spectroradiometer MOD11A2/MYD11A2 at 1 km resolution from the Terra and Aqua platforms, respectively, with equivalent screen-level air temperatures (in the same pixel). We use a transect of 22 in situ weather stations across Kilimanjaro ranging in elevation from 990 to 5803 m, one of the biggest elevational ranges in the world. There are substantial differences between LST and Tair, sometimes up to 20°C. During the day/night land surface temperature tends to be higher/lower than Tair. LST-Tair differences (ΔT) show large variance, particularly during the daytime, and tend to increase with elevation, particularly on the NE slope which faces the morning Sun. Differences are larger in the dry seasons (JF and JJAS) and reduce in cloudy seasons. Healthier vegetation (as measured by normalized difference vegetation index) and increased humidity lead to reduced daytime surface heating above air temperature and lower ΔT, but these relationships weaken with elevation. At high elevations transient snow cover cools LST more than Tair. The predictability of ΔT therefore reduces. It will therefore be challenging to use satellite data at high elevations as a proxy for in situ air temperatures in climate change assessments, especially for daytime Tmax. ΔT is smaller and more consistent at night, so it will be easier to use LST to monitor changes in Tmin.

  5. Calibrating a new proxy for Pleistocene climate change in southern Africa: the Mutual Ostracod Temperature Range method

    NASA Astrophysics Data System (ADS)

    Horne, David; Martens, Koen

    2010-05-01

    The Mutual Ostracod Temperature Range (MOTR) method has so far been applied only in the European Pleistocene, where it is proving effective in producing past air temperature range estimates that compare well with those obtained by other proxy methods (Horne, 2007; Horne & Mezquita, 2008; Holmes et al., in press). As an essential preliminary step towards applying the method in southern Africa, we have calibrated a training set of living ostracod species' distributions against a modern climate dataset and other available environmental data. The modern ostracod dataset is based on material held by the Royal Belgian Institute of Natural Sciences in Brussels, which constitutes the most diverse and comprehensive collection of southern African nonmarine ostracods available anywhere in the world. To date, c. 150 nominal species have been described from southern Africa (Martens, 2001) out of c. 450 species in the total Afrotropical area (Martens et al., 2008). We used an edited dataset comprising a total of 2,118 records of ostracod species from 748 localities in southern Africa, ranging in latitude from approximately 17 degrees S to 35 degrees S. We have explored the potential value and limitations of this training set for the estimation of past climatic parameters including mean July, January and annual air temperatures, precipitation, water conductivity and pH. Holmes, J. A., Atkinson, T., Darbyshire, D. P. F., Horne, D. J., Joordens, J., Roberts, M. B., Sinka, K. J. & Whittaker, J. E. (accepted, in press). Middle Pleistocene climate and hydrological environment at the Boxgrove hominin site (West Sussex, UK) from ostracod records. Quaternary Science Reviews, doi:10.1016/j.quascirev.2009.02.024, 1-13. Horne, D. J. 2007. A Mutual Temperature Range method for Quaternary palaeoclimatic analysis using European nonmarine Ostracoda. Quaternary Science Reviews, 26, 1398-1415. Horne, D. J. & Mezquita, F. 2008. Palaeoclimatic applications of large databases: developing and testing

  6. Air-Cooled Design of a Temperature-Swing Adsorption Compressor for Closed-Loop Air Revitalization Systems

    NASA Technical Reports Server (NTRS)

    Mulloth, Lila M.; Affleck, Dave L.; Rosen, Micha; LeVan, M. Douglas; Wang, Yuan; Cavalcante, Celio L.

    2004-01-01

    The air revitalization system of the International Space Station (ISS) operates in an open loop mode and relies on the resupply of oxygen and other consumables from earth for the life support of astronauts. A compressor is required for delivering the carbon dioxide from a removal assembly to a reduction unit to recover oxygen and thereby closing the air-loop. We have a developed a temperature-swing adsorption compressor (TSAC) for performing these tasks that is energy efficient, quiet, and has no rapidly moving parts. This paper discusses the mechanical design and the results of thermal model validation tests of a TSAC that uses air as the cooling medium.

  7. Some Effects of Air and Fuel Oil Temperatures on Spray Penetration and Dispersion

    NASA Technical Reports Server (NTRS)

    Gelalles, A G

    1930-01-01

    Presented here are experimental results obtained from a brief investigation of the appearance, penetration, and dispersion of oil sprays injected into a chamber of highly heated air at atmospheric pressure. The development of single sprays injected into a chamber containing air at room temperature and at high temperature was recorded by spray photography equipment. A comparison of spray records showed that with the air at the higher temperature, the spray assumed the appearance of thin, transparent cloud, the greatest part of which rapidly disappeared from view. With the chamber air at room temperature, a compact spray with an opaque core was obtained. Measurements of the records showed a decrease in penetration and an increase in the dispersion of the spray injected into the heated air. No ignition of the fuel injected was observed or recorded until the spray particles came in contact with the much hotter walls of the chamber about 0.3 second after the start of injection.

  8. Effects of the air pressure on the wave-packet dynamics of gaseous iodine molecules at room temperature

    NASA Astrophysics Data System (ADS)

    Fan, Rongwei; He, Ping; Chen, Deying; Xia, Yuanqin; Yu, Xin; Wang, Jialing; Jiang, Yugang

    2013-02-01

    Based on ultrafast laser pulses, time-resolved resonance enhancement coherent anti-Stokes Raman scattering (RE-CARS) is applied to investigate wave-packet dynamics in gaseous iodine. The effects of air pressure on the wave-packet dynamics of iodine molecules are studied at pressures ranging from 1.5 Torr to 750 Torr. The RE-CARS signals are recorded in a gas cell filled with a mixture of about 0.3 Torr iodine in air buffer gas at room temperature. The revivals and fractional revival structures in the wave-packet signal are found to gradually disappear with rising air pressure up to 750 Torr, and the decay behaviors of the excited B-state and ground X-state become faster with increasing air pressure, which is due to the collision effects of the molecules and the growing complexity of the spectra at high pressures.

  9. Multi-fractal scaling comparison of the Air Temperature and the Surface Temperature over China

    NASA Astrophysics Data System (ADS)

    Jiang, Lei; Zhang, Jiping; Liu, Xinwei; Li, Fei

    2016-11-01

    The spatial and temporal multi-scaling behaviors between the daily Air Temperature (AT) and the Surface Temperature (ST) over China are compared in about 60-yr observations by Multi-fractal Detrended Fluctuation Analysis (MF-DFA) method. The different fractal phenomena and diversity features in the geographic distribution are found for the AT and ST series using MF-DFA. There are more multi-fractal features for the AT records but less for ST. The respective geographic sites show important scaling differences when compared to the multi-fractal signatures of AT with ST. An interval threshold for 95% confidence level is obtained by shuffling the AT records and the ST records. For the AT records, 93% of all observed stations shows the strong multi-fractal behaviors. In addition, the multi-fractal characteristics decrease with increasing latitude in South China and are obviously strong along the coast. The multi-fractal behaviors of the AT records between the Yangtze River and Yellow River basin and in most regions of Northwest China seem to be weak and not significant, even single mono-fractal features. However, for the ST records, the geographical distributions of multi-fractal phenomenon seem to be in disorder which account for 81% of the stations. The weak multi-fractal behaviors of the ST records are concentrated in North China, most regions of Northeast China.

  10. Impact of aerosol on air temperature in Kuwait

    NASA Astrophysics Data System (ADS)

    Sabbah, I.

    2010-08-01

    This work uses MODIS aerosol optical thickness (AOT) data observed over Kuwait during the 7-year interval 2000-2007. The values of AOT and the Ångström wavelength exponent ( α) show a clear annual cycle. These data are categorized into two catalogues in terms of the values of the AOT of the 870 nm channel ( τ870). One catalogue (71 days) includes days with high values of AOT ( τ870 ≥ 0.75). The most probable "modal" value of α for these days is 0.52. The other catalogue (1162 days) consists of the background days with a modal value ~ 1.1 for the exponent α. This analysis is extended to include water vapor content (WVC), surface wind speed (V), visibility (Vis) and the diurnal temperature range (DTR). Chree's method of superposed-epoch analysis is applied to these parameters in order to compare the variation in the daily averages during days with high AOT values with respect to background days. The high values of AOT during the 71 days are positively correlated with aerosol size, near-surface winds and poor visibility. This concludes that the aerosol particles during these days were mostly dust. The mean daily value of the DTR (Δ T) and visibility reduced significantly during these days. This reduction on DTR is a direct result of increasing the atmospheric opacity due to the presence of dust.

  11. Attribution of precipitation changes on ground-air temperature offset: Granger causality analysis

    NASA Astrophysics Data System (ADS)

    Cermak, Vladimir; Bodri, Louise

    2016-06-01

    This work examines the causal relationship between the value of the ground-air temperature offset and the precipitation changes for monitored 5-min data series together with their hourly and daily averages obtained at the Sporilov Geophysical Observatory (Prague). Shallow subsurface soil temperatures were monitored under four different land cover types (bare soil, sand, short-cut grass and asphalt). The ground surface temperature (GST) and surface air temperature (SAT) offset, ΔT(GST-SAT), is defined as the difference between the temperature measured at the depth of 2 cm below the surface and the air temperature measured at 5 cm above the surface. The results of the Granger causality test did not reveal any evidence of Granger causality for precipitation to ground-air temperature offsets on the daily scale of aggregation except for the asphalt pavement. On the contrary, a strong evidence of Granger causality for precipitation to the ground-air temperature offsets was found on the hourly scale of aggregation for all land cover types except for the sand surface cover. All results are sensitive to the lag choice of the autoregressive model. On the whole, obtained results contain valuable information on the delay time of ΔT(GST-SAT) caused by the rainfall events and confirmed the importance of using autoregressive models to understand the ground-air temperature relationship.

  12. Validation of AIRS V6 Surface Temperature over Greenland with GCN and NOAA Stations

    NASA Technical Reports Server (NTRS)

    Lee, Jae N.; Hearty, Thomas; Cullather, Richard; Nowicki, Sophie; Susskind, Joel

    2016-01-01

    This work compares the temporal and spatial characteristics of the AIRSAMSU (Atmospheric Infrared Sounder Advanced Microwave Sounding Unit A) Version 6 and MODIS (Moderate resolution Imaging Spectroradiometer) Collection 5 derived surface temperatures over Greenland. To estimate uncertainties in space-based surface temperature measurements, we re-projected the MODIS Ice Surface Temperature (IST) to 0.5 by 0.5 degree spatial resolution. We also re-gridded AIRS Skin Temperature (Ts) into the same grid but classified with different cloud conditions and surface types. These co-located data sets make intercomparison between the two instruments relatively straightforward. Using this approach, the spatial comparison between the monthly mean AIRS Ts and MODIS IST is in good agreement with RMS 2K for May 2012. This approach also allows the detection of any long-term calibration drift and the careful examination of calibration consistency in the MODIS and AIRS temperature data record. The temporal correlations between temperature data are also compared with those from in-situ measurements from GC-Net (GCN) and NOAA stations. The coherent time series of surface temperature evident in the correlation between AIRS Ts and GCN temperatures suggest that at monthly time scales both observations capture the same climate signal over Greenland. It is also suggested that AIRS surface air temperature (Ta) can be used to estimate the boundary layer inversion.

  13. Investigation of the impact of extreme air temperature on river water temperature: case study of the heat episode 2013.

    NASA Astrophysics Data System (ADS)

    Weihs, Philipp; Trimmel, Heidelinde; Goler, Robert; Formayer, Herbert; Holzapfel, Gerda; Rauch, Hans Peter

    2014-05-01

    Water stream temperature is a relevant factor for water quality since it is an important driver of water oxygen content and in turn also reduces or increases stress on the aquatic fauna. The water temperature of streams is determined by the source and inflow water temperature, by the energy balance at the stream surface and by the hydrological regime of the stream. Main factors driving the energy balance of streams are radiation balance and air temperature which influences the sensitive and latent heat flux. The present study investigates the impact of the heat episode of summer 2013 on water temperature of two lowland rivers in south eastern Austria. Within the scope of the project BIO_CLIC routine measurements of water temperature at 33 locations alongside the rivers Pinka and Lafnitz have been performed since spring 2012. In addition meteorological measurements of global shortwave and longwave radiation, air temperature, wind and air humidity have been carried out during this time. For the same time period, data of discharge and water levels of both rivers were provided by the public hydrological office. The heat episode of summer 2013 started, according to the Kysely- definition, on 18 July and lasted until 14 August. The highest air temperature ever recorded in Austria was reported on 8 August at 40.5°C. In Güssing, which is located within the project area, 40.0 °C were recorded. In the lower reaches of the river Pinka, at the station Burg the monthly mean water temperature of August 2013 was with more than 22°C, 1°C higher than the mean water temperature of the same period of the previous years. At the same station, the maximum water temperature of 27.1°C was recorded on 29 July, 9 days prior to the air temperature record. Analysis shows that at the downstream stations the main driving parameter is solar radiation whereas at the upstream stations a better correlation between air temperature and water temperature is obtained. Using the extensive data set

  14. Comparison of Near-Surface Air Temperatures and MODIS Ice-Surface Temperatures at Summit, Greenland (2008-2013)

    NASA Technical Reports Server (NTRS)

    Shuman, Christopher A.; Hall, Dorothy K.; DiGirolamo, Nicolo E.; Mefford, Thomas K.; Schnaubelt, Michael J.

    2014-01-01

    We have investigated the stability of the MODerate resolution Imaging Spectroradiometer (MODIS) infrared-derived ice surface temperature (IST) data from Terra for use as a climate quality data record. The availability of climate quality air temperature data (TA) from a NOAA Global Monitoring Division observatory at Greenlands Summit station has enabled this high temporal resolution study of MODIS ISTs. During a 5 year period (July 2008 to August 2013), more than 2500 IST values were compared with 3-minute average TA values derived from the 1-minute data from NOAAs primary 2 m air temperature sensor. These data enabled an expected small offset between air and surface temperatures at this the ice sheet location to be investigated over multiple annual cycles.

  15. Wide Pressure Range Measurement due to the Exchange of Heater Driving of the Temperature Difference Sensor

    NASA Astrophysics Data System (ADS)

    Takashima, Noriaki; Kimura, Mitsuteru

    We have extended measurable pressure range of the thin film Pirani vacuum sensor that is still sensitive above 1×105 Pa (1 atmosphere). In our thin film Pirani vacuum sensor, our proposed temperature difference sensor of the short circuit Seebeck-current detection type thermocouple is used in order to get extremely high sensitivity, especially both in very low pressure range and in higher pressure range than 1×104 Pa. In our new pressure sensor the cantilever type sensing region, in which a microheater and two thermocouples are formed to measure the temperature difference, is adopted. Therefore, we can use the null method to measure very small pressure accurately in the high vacuum range (low pressure range). On the other hand in the higher pressure than 1×104 Pa., we could expand the pressure range by adoption of the vibration of the sensing cantilever based on the sudden heating due to the exchange of heater driving. We have achieved much wider measurable pressure range over 8 digits by use of our new simple thin film Pirani vacuum sensor than that of the traditional one.

  16. Tonopah Test Range Air Monitoring: CY2012 Meteorological, Radiological, and Airborne Particulate Observations

    SciTech Connect

    Mizell, Steve A; Nikolich, George; Shadel, Craig; McCurdy, Greg; Miller, Julianne J

    2013-07-01

    In 1963, the Atomic Energy Commission (AEC), predecessor to the US Department of Energy (DOE), implemented Operation Roller Coaster on the Tonopah Test Range (TTR) and an adjacent area of the Nevada Test and Training Range (NTTR) (formerly the Nellis Air Force Range (NAFR)). Operation Roller Coaster consisted of four tests in which chemical explosions were detonated in the presence of nuclear devices to assess the dispersal of radionuclides and evaluate the effectiveness of storage structures to contain the ejected radionuclides. These tests resulted in dispersal of plutonium over the ground surface downwind of the test ground zero. Three tests, Clean Slate 1, 2, and 3, were conducted on the TTR in Cactus Flat; the fourth, Double Tracks, was conducted in Stonewall Flat on the NTTR. DOE is working to clean up and close all four sites. Substantial cleaned up has been accomplished at Double Tracks and Clean Slate 1. Cleanup of Clean Slate 2 and 3 is on the DOE planning horizon for some time in the next several years. The Desert Research Institute installed two monitoring stations, number 400 at the Sandia National Laboratories Range Operations Center and number 401 at Clean Slate 3, in 2008 and a third monitoring station, number 402 at Clean Slate 1, in 2011 to measure radiological, meteorological, and dust conditions. The primary objectives of the data collection and analysis effort are to (1) monitor the concentration of radiological parameters in dust particles suspended in air, (2) determine whether winds are re-distributing radionuclides or contaminated soil material, (3) evaluate the controlling meteorological conditions if wind transport is occurring, and (4) measure ancillary radiological, meteorological, and environmental parameters that might provide insight to the above assessments. The following observations are based on data collected during CY2012. The mean annual concentration of gross alpha and gross beta is highest at Station 400 and lowest at Station

  17. Development of ceramic lithium-electrolyte based carbon dioxide sensors for temperatures ranging from ambient to high temperature

    NASA Astrophysics Data System (ADS)

    Lee, Inhee

    Solid-state electrochemical CO2 gas sensors composed of an electrolyte and two porous electrodes have been used extensively in the automobile and bio-chemical industry. Based on the field of application, the working temperature of the sensor ranges from room temperature to 600°C. Two potentiometric CO2 sensors that work at different temperature ranges were developed in this work. A potentiometric CO2 gas sensor with Li3PO 4 electrolyte and BaCO3 coated Li2CO3 sensing electrode was developed and the sensing electrode was characterized in order to understand its sensing mechanism under humid conditions. This potentiometric CO2 sensor showed humidity-interference-free sensing response for high CO2 concentrations (5˜25%) at high temperatures (T > 400°C). In addition, the sensor showed good reproducibility and long-term stability under humid conditions. In the sensing electrode, the BaCO 3 layer improved the resistance against humidity as a chemical barrier, while the inner Li2CO3 layer was responsible for the CO2 sensing. However, the sensor in which the eutectic layer covered the entire sensing electrode showed good sensing behavior under dry and humid conditions. Lately, low-temperature CO2 sensors have been attracting attention due to their low power consumption and easy sensor miniaturization, since a heater is unnecessary. We have developed a low-temperature CO2 sensor based on lithium lanthanum titanate (LLT) electrolyte in dry conditions that requires further improvement. Lithium lanthanum titanate (LLT) electrolytes were prepared by a conventional solid-state method. The impedance of the LLT electrolyte was measured over the temperature range of 300 to 473 K and the frequency range of 5 Hz and 13 MHz. Activation energies for the Li ionic conduction for grain boundary and grain were estimated to be 0.47 and 0.31 eV, respectively. It was found that LLT is a good ionic conductor at low temperatures and a good candidate as an electrolyte for low-temperature

  18. Wide-temperature range operation supercapacitors from nanostructured activated carbon fabric

    NASA Astrophysics Data System (ADS)

    Hung, Kaihsuan; Masarapu, Charan; Ko, Tsehao; Wei, Bingqing

    Electrochemical power sources that offer high energy and power densities and, can also withstand a harsh temperature range have become extremely desirable in applications ranging from civilian portable electronic devices to military weapons. In this report, we demonstrated a wide temperature withstanding supercapacitor which can be operated from 100 °C to -40 °C within a voltage window from -2 V to 2 V. The performance of the supercapacitor coin cells, assembled with nanostructured activated carbon fabric (ACF) as the electrode material and 1 M tetraethylammonium tetrafluoroborate (TEABF 4) in polypropylene carbonate (PC) solution as the electrolyte, was systematically studied within the set temperature window. The ACF supercapacitor yielded ideal rectangular shapes in cyclic voltammograms within 0-100 °C with an average mass capacitance of 90 F g -1 and, 60 F g -1 at -25 °C. The capacitance was still over 20 F g -1 at the extremely low temperature of -40 °C. Another exciting feature of the ACF supercapacitors was that they resumed their room temperature capacitance when cooled from 100 °C and defrosted from -40 °C, demonstrating an excellent repeatability and stability. The charge-discharge behavior of the ACF supercapacitors showed long-cycle stability at extreme temperatures. These high electrochemical performances make this type of supercapacitors very promising in many practical applications.

  19. Simultaneous measurement of temperature and velocity of air flow over 1000°C using two color phosphor thermometry

    NASA Astrophysics Data System (ADS)

    Fukuta, Masatoshi; Someya, Satoshi; Munakata, Tetsuo; LCS Team

    2016-11-01

    Thermal barrier coatings were applied to the gas turbines and the internal combustion engines for the high thermal efficiency. The evaluation and the improvement of coatings require to measure transient gaseous flow near the wall with coatings. An aim of this study is to combine a two color phosphor thermometry with the PIV to measure simultaneously temperature and velocity of the gas over 1000°C. The temperature and velocity distribution of an impinging jet of high temperature air was simultaneously visualized in experiments. The temperature was estimated from an intensity ratio of luminescent in different ranges of wavelength, 500 600 nm and 400 480 nm. Uncertainty of measured temperature was less than 10°C. Temperatures measured by the developed method and by thermocouples were agreed well. The measured velocity by the PIV with phosphor particles were also agreed well with the velocity measured by a Laser Doppler Velocimeter.

  20. Dissociation and ionization equilibria of deuterium fluid over a wide range of temperatures and densities

    SciTech Connect

    Zaghloul, Mofreh R.

    2015-06-15

    We investigate the dissociation and ionization equilibria of deuterium fluid over a wide range of temperatures and densities. The partition functions for molecular and atomic species are evaluated, in a statistical-mechanically consistent way, implementing recent developments in the literature and taking high-density effects into account. A new chemical model (free energy function) is introduced in which the fluid is considered as a mixture of diatomic molecules, atoms, ions, and free electrons. Intensive short range hard core repulsion is taken into account together with partial degeneracy of free electrons and Coulomb interactions among charged particles. Samples of computational results are presented as a set of isotherms for the degree of ionization, dissociated fraction of molecules, pressure, and specific internal energy for a wide range of densities and temperatures. Predictions from the present model calculations show an improved and sensible physical behavior compared to other results in the literature.

  1. Modeling Validation and Control Analysis for Controlled Temperature and Humidity of Air Conditioning System

    PubMed Central

    Lee, Jing-Nang; Lin, Tsung-Min

    2014-01-01

    This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for controlling the air mass flow rate, humidifying capacity, and heating, capacity. The simulation results show that the temperature and humidity are stable at 541 sec, the disturbance of temperature is only 0.14°C, 0006 kgw/kgda in steady-state error of humidity ratio, and the error rate is only 7.5%. The results prove that the proposed system is an effective controlled temperature and humidity of an air conditioning system. PMID:25250390

  2. Modeling validation and control analysis for controlled temperature and humidity of air conditioning system.

    PubMed

    Lee, Jing-Nang; Lin, Tsung-Min; Chen, Chien-Chih

    2014-01-01

    This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for controlling the air mass flow rate, humidifying capacity, and heating, capacity. The simulation results show that the temperature and humidity are stable at 541 sec, the disturbance of temperature is only 0.14 °C, 0006 kg(w)/kg(da) in steady-state error of humidity ratio, and the error rate is only 7.5%. The results prove that the proposed system is an effective controlled temperature and humidity of an air conditioning system.

  3. Temperature and frequency characteristics of low-loss MnZn ferrite in a wide temperature range

    NASA Astrophysics Data System (ADS)

    Sun, Ke; Lan, Zhongwen; Yu, Zhong; Xu, Zhiyong; Jiang, Xiaona; Wang, Zihui; Liu, Zhi; Luo, Ming

    2011-05-01

    A low-loss Mn0.7Zn0.24Fe2.06O4 ferrite has been prepared by a solid-state reaction method. The MnZn ferrite has a high initial permeability, μi (3097), a high saturation induction, Bs (526 mT), a high Curie temperature, Tc (220 °C), and a low core loss, PL (≤ 415 kW/m3) in a wide temperature (25-120 °C) and frequency (10-100 kHz) range. As the temperature increases, an initial decrease followed by a subsequent increase of hysteresis loss, Ph, and eddy current loss, Pe is observed. Both Ph and Pe increase with increasing frequency. When f ≥ 300 kHz, a residual loss, Pr, appears. Pe increases with increasing temperature and frequency. The temperature and frequency dependence of Ph can be explained by irreversible domain wall movements, Pe by the skin effect, and Pr by domain wall resonance, respectively.

  4. An alternate method for achieving temperature control in the -130 C to 75 C range

    NASA Technical Reports Server (NTRS)

    Johnson, Kenneth R.; Anderson, Mark R.; Lane, Robert W.; Cortez, Maximo G.

    1992-01-01

    Thermal vacuum testing often requires temperature control of chamber shrouds and heat exchangers within the -130 C to 75 C range. There are two conventional methods which are normally employed to achieve control through this intermediate temperature range: (1) single-pass flow where control is achieved by alternately pulsing hot gaseous nitrogen (GN2) and cold LN2 into the feed line to yield the setpoint temperature; and (2) closed-loop circulation where control is achieved by either electrically heating or LN2 cooling the circulating GN2 to yield the setpoint temperature. A third method, using a mass flow ratio controller along with modulating control valves on GN2 and LN2 lines, provides excellent control but equipment for this method is expensive and cost-prohibitive for all but long-term continuous processes. The single-pass method provides marginal control and can result in unexpected overcooling of the test article from even a short pulse of LN2. The closed-loop circulation method provides excellent control but requires an expensive blower capable of operating at elevated pressures and cryogenic temperatures. Where precise control is needed (plus or minus 2 C), single-pass flow systems typically have not provided the precision required, primarily because of overcooling temperature excursions. Where several individual circuits are to be controlled at different temperatures, the use of expensive cryogenic blowers for each circuit is also cost-prohibitive, especially for short duration of one-of-a-kind tests. At JPL, a variant of the single-pass method was developed that was shown to provide precise temperature control in the -130 C to 75 C range while exhibiting minimal setpoint overshoot during temperature transitions. This alternate method uses a commercially available temperature controller along with a GN2/LN2 mixer to dampen the amplitude of cold temperature spikes caused by LN2 pulsing. The design of the GN2/LN2 mixer, the overall control system

  5. Auto-ignitions of a methane/air mixture at high and intermediate temperatures

    NASA Astrophysics Data System (ADS)

    Leschevich, V. V.; Martynenko, V. V.; Penyazkov, O. G.; Sevrouk, K. L.; Shabunya, S. I.

    2016-09-01

    A rapid compression machine (RCM) and a shock tube (ST) have been employed to study ignition delay times of homogeneous methane/air mixtures at intermediate-to-high temperatures. Both facilities allow measurements to be made at temperatures of 900-2000 K, at pressures of 0.38-2.23 MPa, and at equivalence ratios of 0.5, 1.0, and 2.0. In ST experiments, nitrogen served as a diluent gas, whereas in RCM runs the diluent gas composition ranged from pure nitrogen to pure argon. Recording pressure, UV, and visible emissions identified the evolution of chemical reactions. Correlations of ignition delay time were generated from the data for each facility. At temperatures below 1300 K, a significant reduction of average activation energy from 53 to 15.3 kcal/mol was obtained. Moreover, the RCM data showed significant scatter that dramatically increased with decreasing temperature. An explanation for the abnormal scatter in the data was proposed based on the high-speed visualization of auto-ignition phenomena and experiments performed with oxygen-free and fuel-free mixtures. It is proposed that the main reason for such a significant reduction of average activation energy is attributable to the premature ignition of ultrafine particles in the reactive mixture.

  6. A temperature inversion-induced air pollution process as analyzed from Mie LiDAR data.

    PubMed

    Wu, Wanning; Zha, Yong; Zhang, Jiahua; Gao, Jay; He, Junliang

    2014-05-01

    A severe air pollution event in the Xianlin District of Nanjing City, China during 23-24 December 2012 was analyzed in terms of aerosol extinction coefficient and AOT retrieved from Mie scattering LiDAR data, in conjunction with in situ particulate concentrations measured near the Earth's surface, and the Weather Research Forecast-derived meteorological conditions. Comprehensive analyses of temperature, humidity, wind direction and velocity, and barometric pressure led to the conclusion that this pollution event was caused by advection inversion. In the absence of temperature inversion, the atmosphere at a height of 0.15 km has a relatively large extinction coefficient. In situ measured particulates exhibited a very large diurnal range. However, under the influence of turbulences, AOT was rather stable with a value <0.2 at an altitude below 0.8 km. Advection inversion appeared at 9:00 AM on 24 December, and did not dissipate until 22:00 PM. This temperature inversion, to some degree, inhibited the dispersion of near-surface particulates. Affected by this temperature inversion, the atmospheric extinction coefficient near the surface became noticeably larger. Near-surface particulates hardly varied at a concentration around 0.2mg/m(3). AOT at an altitude below 0.8 km rose to 0.31.

  7. Perceiving nasal patency through mucosal cooling rather than air temperature or nasal resistance.

    PubMed

    Zhao, Kai; Blacker, Kara; Luo, Yuehao; Bryant, Bruce; Jiang, Jianbo

    2011-01-01

    Adequate perception of nasal airflow (i.e., nasal patency) is an important consideration for patients with nasal sinus diseases. The perception of a lack of nasal patency becomes the primary symptom that drives these patients to seek medical treatment. However, clinical assessment of nasal patency remains a challenge because we lack objective measurements that correlate well with what patients perceive. The current study examined factors that may influence perceived patency, including air temperature, humidity, mucosal cooling, nasal resistance, and trigeminal sensitivity. Forty-four healthy subjects rated nasal patency while sampling air from three facial exposure boxes that were ventilated with untreated room air, cold air, and dry air, respectively. In all conditions, air temperature and relative humidity inside each box were recorded with sensors connected to a computer. Nasal resistance and minimum airway cross-sectional area (MCA) were measured using rhinomanometry and acoustic rhinometry, respectively. General trigeminal sensitivity was assessed through lateralization thresholds to butanol. No significant correlation was found between perceived patency and nasal resistance or MCA. In contrast, air temperature, humidity, and butanol threshold combined significantly contributed to the ratings of patency, with mucosal cooling (heat loss) being the most heavily weighted predictor. Air humidity significantly influences perceived patency, suggesting that mucosal cooling rather than air temperature alone provides the trigeminal sensation that results in perception of patency. The dynamic cooling between the airstream and the mucosal wall may be quantified experimentally or computationally and could potentially lead to a new clinical evaluation tool.

  8. Analysis of surface air temperature variations and local urbanization effects on central Yunnan Plateau, SW China

    NASA Astrophysics Data System (ADS)

    He, Yunling; Wu, Zhijie; Liu, Xuelian; Deng, Fuying

    2016-10-01

    With the surface air temperature (SAT) data at 37 stations on Central Yunnan Plateau (CYP) for 1961-2010 and the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime light data, the temporal-spatial patterns of the SAT trends are detected using Sen's Nonparametric Estimator of Slope approach and MK test, and the impact of urbanization on surface warming is analyzed by comparing the differences between the air temperature change trends of urban stations and their corresponding rural stations. Results indicated that annual mean air temperature showed a significant warming trend, which is equivalent to a rate of 0.17 °C/decade during the past 50 years. Seasonal mean air temperature presents a rising trend, and the trend was more significant in winter (0.31 °C/decade) than in other seasons. Annual/seasonal mean air temperature tends to increase in most areas, and higher warming trend appeared in urban areas, notably in Kunming city. The regional mean air temperature series was significantly impacted by urban warming, and the urbanization-induced warming contributed to approximately 32.3-62.9 % of the total regional warming during the past 50 years. Meantime, the urbanization-induced warming trend in winter and spring was more significant than that in summer and autumn. Since 1985, the urban heat island (UHI) intensity has gradually increased. And the urban temperatures always rise faster than rural temperatures on the CYP.

  9. Comparison of Vertical Soundings and Sidewall Air Temperature Measurements in a Small Alpine Basin.

    NASA Astrophysics Data System (ADS)

    Whiteman, C. David; Eisenbach, Stefan; Pospichal, Bernhard; Steinacker, Reinhold

    2004-11-01

    Tethered balloon soundings from two sites on the floor of a 1-km-diameter limestone sinkhole in the eastern Alps are compared with pseudovertical temperature “soundings” from three lines of temperature dataloggers on the basin's northwest, southwest, and southeast sidewalls. Under stable nighttime conditions with low background winds, the pseudovertical profiles from all three lines were good proxies for free air temperature soundings over the basin center, with a mean nighttime cold temperature bias of about 0.4°C and a standard deviation of 0.4°C. Cold biases were highest in the upper basin where relatively warm air subsides to replace air that spills out of the basin through the lowest-altitude saddle. On a windy night, standard deviations increased to 1° 2°C. After sunrise, the varying exposures of the dataloggers to sunlight made the pseudovertical profiles less useful as proxies for free air soundings. The good correspondence between sidewall and free air temperatures during high-static-stability conditions suggests that sidewall soundings can be used to monitor temperatures, temperature gradients, and temperature inversion evolution in the sinkhole. Sidewall soundings can produce more frequent profiles at lower cost than can tethersondes or rawinsondes, and extension of these findings to other enclosed or semienclosed topographies may enhance future basic meteorological research or support applications studies in agriculture, forestry, air pollution, and land use planning.


  10. Temperature-dependent Goos-Hänchen shift in the terahertz range

    NASA Astrophysics Data System (ADS)

    Zang, Mengdi; He, Ting; Zhang, Bo; Zhong, Liang; Shen, Jingling

    2016-07-01

    In this work, an observation of Goos-Hänchen shift in the terahertz range on a metal surface with a change in temperature is reported. A s-polarized terahertz wave incident at 45° onto an aluminum surface produces a positive GH shift that increases with temperature. We used an interference method by observing the change of interference fringes of two THz beams to verify the existence of the GH shift and indirectly measured the quantity of it. Based on experimental data and theoretical analysis, the increase of GH shift on the aluminum surface as a function of temperature between 23 °C and 101 °C has been obtained. Considering the effect of the thermal expansion, the maximum variation of GH shift is 267.2 μm with the temperature changing 78 °C.

  11. Communication: Anomalous temperature dependence of the intermediate range order in phosphonium ionic liquids

    SciTech Connect

    Hettige, Jeevapani J.; Kashyap, Hemant K.; Margulis, Claudio J.

    2014-03-21

    In a recent article by the Castner and Margulis groups [Faraday Discuss. 154, 133 (2012)], we described in detail the structure of the tetradecyltrihexylphosphonium bis(trifluoromethylsulfonyl)-amide ionic liquid as a function of temperature using X-ray scattering, and theoretical partitions of the computationally derived structure function. Interestingly, and as opposed to the case in most other ionic-liquids, the first sharp diffraction peak or prepeak appears to increase in intensity as temperature is increased. This phenomenon is counter intuitive as one would expect that intermediate range order fades as temperature increases. This Communication shows that a loss of hydrophobic tail organization at higher temperatures is counterbalanced by better organization of polar components giving rise to the increase in intensity of the prepeak.

  12. Combustion of Gaseous Fuels with High Temperature Air in Normal- and Micro-gravity Conditions

    NASA Technical Reports Server (NTRS)

    Wang, Y.; Gupta, A. K.

    2001-01-01

    The objective of this study is determine the effect of air preheat temperature on flame characteristics in normal and microgravity conditions. We have obtained qualitative (global flame features) and some quantitative information on the features of flames using high temperature combustion air under normal gravity conditions with propane and methane as the fuels. This data will be compared with the data under microgravity conditions. The specific focus under normal gravity conditions has been on determining the global flame features as well as the spatial distribution of OH, CH, and C2 from flames using high temperature combustion air at different equivalence ratio.

  13. Conducting thermomechanical fatigue test in air at light water reactor relevant temperature intervals

    NASA Astrophysics Data System (ADS)

    Ramesh, Mageshwaran; Leber, Hans J.; Diener, Markus; Spolenak, Ralph

    2011-08-01

    In Light Water Reactors (LWR), many structural components are made of austenitic stainless steels (SS). These components are subject to extreme conditions, such as large temperature gradients and pressure loads during service. Hence, the fatigue and fracture behavior of austenitic SS under these conditions has evoked consistent interest over the years. Most studies dealing with this problem in the past, investigated the isothermal fatigue (IF) condition, which is not the case in the service, and less attention has been paid to thermomechanical fatigue (TMF). Moreover, the existing codes of practice and standards for TMF testing are mainly derived from the high temperature TMF tests ( T mean > 400 °C). This work presents the development of a facility to perform TMF tests under LWR relevant temperature interval in air. The realized testing parameters and tolerances are compared with the recommendations of existing codes of practice and standards from high temperature tests. The effectiveness of the testing facility was verified with series of TMF and IF tests performed on specimens made out of a commercial austenitic SS TP347 pipe material. The results revealed that the existing tolerances in standards are quite strict for the application of lower temperature ranges TMF tests. It was found that the synchronous, in-phase (IP) TMF tested specimens possess a higher lifetime than those subjected to the asynchronous, out-of-phase (OP) TMF and IF at T max in the investigated strain range for austenitic SS. Nevertheless, the fatigue lifetime of all the test conditions was similar in the engineering scale.

  14. Thermal Coupling Between Air and Ground Temperatures in the CMIP5 Historical and Future Simulations

    NASA Astrophysics Data System (ADS)

    García-García, A.; Cuesta-Valero, F. J.; Smerdon, J. E.; Beltrami, H.

    2015-12-01

    The thermal coupling between air and ground temperatures is investigated herein for General Circulation Models (GCMs) that participated in the fifth phase of the Coupled Model Intercomparison Project (CMIP5). For each simulation, we evaluate the regional relationship between air and ground temperatures to study surface energy fluxes and the attenuation of the annual temperature signal across the air-ground interface and into the shallow subsurface for North America. Our results show that the transport of energy across the air-ground interface and into the shallow subsurface is different across GCMs and is dependent on the land surface models that each employs. The variability of the difference between air and ground temperatures is high among simulations and is not dependent on the depth of the bottom boundary of the subsurface soil model. The difference between air and ground temperatures differs significantly from observations. Additionally, while the variability among GCMs can be explained by the physics of the land surface models, the regional variability of the air-ground coupling is associated with the model treatment of soil properties as well as snow and vegetation processes within GCMs. The difference between air and ground temperatures at high latitudes within the majority of the CMIP5 models is directly proportional to the amount of snow on the ground, due to the insulating effect of snow cover. On the other hand, the difference between air and ground temperatures at low latitudes within some of the CMIP5 models is inversely proportional to the vegetation cover (leaf area index), due to changes in latent and sensible heat fluxes. The large variability among GCMs and the marked dependency of the results on the choice of the land-surface model illustrates the need for improving the simulation of air-ground coupling in land-surface models towards a robust simulation of near-surface processes, such as permafrost and soil carbon stability within GCMs.

  15. All-solid-state lithium-oxygen battery with high safety in wide ambient temperature range.

    PubMed

    Kitaura, Hirokazu; Zhou, Haoshen

    2015-08-21

    There is need to develop high energy storage devices with high safety to satisfy the growing industrial demands. Here, we show the potential to realize such batteries by assembling a lithium-oxygen cell using an inorganic solid electrolyte without any flammable liquid or polymer materials. The lithium-oxygen battery using Li1.575Al0.5Ge1.5(PO4)3 solid electrolyte was examined in the pure oxygen atmosphere from room temperature to 120 °C. The cell works at room temperature and first full discharge capacity of 1420 mAh g(-1) at 10 mA g(-1) (based on the mass of carbon material in the air electrode) was obtained. The charge curve started from 3.0 V, and that the majority of it lay below 4.2 V. The cell also safely works at high temperature over 80 °C with the improved battery performance. Furthermore, fundamental data of the electrochemical performance, such as cyclic voltammogram, cycle performance and rate performance was obtained and this work demonstrated the potential of the all-solid-state lithium-oxygen battery for wide temperature application as a first step.

  16. Coherent-interference-induced transparency based on long-range air-hole assisted subwavelength waveguides

    NASA Astrophysics Data System (ADS)

    Zhou, Wen; Huang, Xu Guang; Tan, Qilong; Liang, Yao; Lao, Jieer; Chen, Zanhui

    2014-11-01

    A novel coherent-interference-induced transparency (CIT) system consisting of two coupled and detuned double-sided-branch (DSB) filters in a long-range air-hole assisted subwavelength (LR-AHAS) waveguide has been proposed and numerically demonstrated. The resonant wavelength, maximum transmittance, full width at half maximum (FWHM) and phase dispersion of the transparent window can be effectively tuned by adjusting the detuning and phase-shift between two coupled DSB filters, and FWHM can be suppressed to as small as 1.6 nm, which is much narrower than that of an individual resonator in an LR-AHAS waveguide. The FWHMs of 3.2 nm and 5.2 nm with the corresponding group refractive indices ng of 73 and 45 have been respectively demonstrated. In addition, multiple transparent peaks with an average bandwidth of 3.6 nm and high transmittance of 0.74 can be achieved by cascading more detuned DSB filters into the system. It provides a new approach to develop tunable high-channel-count bandpass filters and optical buffers based on the LR-AHAS waveguide platform for large-scale photonic integrations.

  17. Air Quality Impacts of Oil and Gas Operations in the Northern Colorado Front Range

    NASA Astrophysics Data System (ADS)

    Helmig, D.; Thompson, C. R.; Jacques, H.; Smith, K. R.; Terrell, R. M.

    2014-12-01

    Exceedences of the US EPA National Ambient Air Quality Standard (NAAQS) for surface ozone have been reported from monitoring sites in the Northern Colorado Front Range (NCFR) for more than fifteen years during summer. Comparison of ozone records from the NCFR clearly show that ozone primarily results from regional photochemical daytime production. Recent trend analyses do not show an improvement of surface ozone despite efforts by the State of Colorado to curb ozone precursor emissions. Our review of atmospheric volatile organic compound (VOC) measurements from historic and recent monitoring shows significant spatial increases of atmospheric VOC towards the oil and gas development area in Weld County, NW of the Denver-Boulder metropolitan region. Secondly, analyses of VOC trends and VOC signatures show an overall increase of oil and gas associated VOC relative to other VOC sources. These analyses suggest that oil and gas emissions are playing and increasing role in ozone production in the NCFR and that reductions of oil and gas emissions would be beneficial for lowering surface ozone and attainment of the ozone NAAQS.

  18. In situ radiological surveying at the Double Tracks site, Nellis Air Force Range, Tonopah, Nevada

    SciTech Connect

    Riedhauser, S.R.; Tipton, W.J.

    1996-04-01

    A team from the Remote Sensing Laboratory conducted a series of in situ radiological measurements at the Double Tracks site on the Nellis Air Force Range just east of Goldfield, Nevada, during the periods of April 10-13 and June 5-9, 1995. The survey team measured the terrestrial gamma radiation at the site to determine the levels of natural and man-made radiation. This site includes the areas covered by previous surveys conducted from 1962 through 1993. The main purpose of the first expedition was to assess several new techniques for characterizing sites with dispersed plutonium. The two purposes of the second expedition were to characterize the distribution of transuranic contamination (primarily plutonium) at the site by measuring the gamma rays from americium-241 and to assess the performance of the two new detector platforms. Both of the new platforms performed well, and the characterization of the americium-241 activity at the site was completed. Several plots compare these ground-based system measurements and the 1993 aerial data. The agreement is good considering the systems are characterized and calibrated through independent means. During the April expedition, several methods for measuring the depth distribution of americium-241 in the field were conducted as a way of quickly and reliably obtaining depth profiles without the need to wait for laboratory analysis. Two of the methods were not very effective, but the results of the third method appear very promising.

  19. Preliminary development of a VTOL unmanned air vehicle for the close-range mission

    NASA Astrophysics Data System (ADS)

    Kress, Gregory A.

    1992-09-01

    The preliminary development of a full-scale Vertical Takeoff and Landing (VTOL) Unmanned Air Vehicle (UAV) for the Close-Range mission was completed at the Naval Postgraduate School (NPS). The vehicle was based on half-scale ducted-fan investigations performed at the UAV Flight Research Lab. The resulting design is a fixed-duct, tail-sitter UAV with a canard-configured horizontal stabilizer. Major airframe components are used from previous UAV's and include the wings from a U.S. Army Aquila and the ducted fan from the U.S. Marine Corps AROD. Accomplishments include: (1) the design and fabrication of a carry-through spar, and (2) the design and construction of an engine test stand. The through spar was designed using finite element analysis and constructed from composite materials. The purpose of the test stand is to measure torque, horsepower, and thrust of an entire ducted fan or an individual engine. Completion of this thesis will pave the way for future NPS research into the growing interest in VTOL UAV technology.

  20. Groundwater flow and contaminant transport modelling at an air weapons range

    NASA Astrophysics Data System (ADS)

    Bordeleau, Geneviève; Martel, Richard; Schäfer, Dirk; Ampleman, Guy; Thiboutot, Sonia

    2008-07-01

    Numerical modelling was done at the Cold Lake Air Weapons Range, Canada, to test whether the dissolved RDX and nitrate detected in groundwater come from the same sources, and to predict whether contamination poses a threat to the surface water receptors near the site. Military live fire training activities may indeed pose a risk of contamination to groundwater resources, however field investigations on military bases are quite recent, and little information is available on the long-term behaviour of munition residues related contaminants. Very limited information was available about the contaminant source zones, which were assigned based on our knowledge of current training activities. The RDX plume was well represented with the model, but the heterogeneous distribution of nitrate concentrations was more difficult to reproduce. It was nonetheless determined that both contaminants originate from the same areas. According to the model, both contaminants should reach the nearby river, but concentrations in the river should remain very low if the source zone concentration does not change. Finally, the model allowed the recommendation of a new location for the main bombing target, which would offer added protection to the river and the lake into which it flows.

  1. Multichannel temperature controller for hot air solar house

    NASA Technical Reports Server (NTRS)

    Currie, J. R.

    1979-01-01

    This paper describes an electronic controller that is optimized to operate a hot air solar system. Thermal information is obtained from copper constantan thermocouples and a wall-type thermostat. The signals from the thermocouples are processed through a single amplifier using a multiplexing scheme. The multiplexing reduces the component count and automatically calibrates the thermocouple amplifier. The processed signals connect to some simple logic that selects one of the four operating modes. This simple, inexpensive, and reliable scheme is well suited to control hot air solar systems.

  2. High-precision diode-laser-based temperature measurement for air refractive index compensation

    SciTech Connect

    Hieta, Tuomas; Merimaa, Mikko; Vainio, Markku; Seppae, Jeremias; Lassila, Antti

    2011-11-01

    We present a laser-based system to measure the refractive index of air over a long path length. In optical distance measurements, it is essential to know the refractive index of air with high accuracy. Commonly, the refractive index of air is calculated from the properties of the ambient air using either Ciddor or Edlen equations, where the dominant uncertainty component is in most cases the air temperature. The method developed in this work utilizes direct absorption spectroscopy of oxygen to measure the average temperature of air and of water vapor to measure relative humidity. The method allows measurement of temperature and humidity over the same beam path as in optical distance measurement, providing spatially well-matching data. Indoor and outdoor measurements demonstrate the effectiveness of the method. In particular, we demonstrate an effective compensation of the refractive index of air in an interferometric length measurement at a time-variant and spatially nonhomogeneous temperature over a long time period. Further, we were able to demonstrate 7 mK RMS noise over a 67 m path length using a 120 s sample time. To our knowledge, this is the best temperature precision reported for a spectroscopic temperature measurement.

  3. Temperature variability in the Iberian Range since 1602 inferred from tree-ring records

    NASA Astrophysics Data System (ADS)

    Tejedor, Ernesto; Ángel Saz, Miguel; María Cuadrat, José; Esper, Jan; de Luis, Martín

    2017-02-01

    Tree rings are an important proxy to understand the natural drivers of climate variability in the Mediterranean Basin and hence to improve future climate scenarios in a vulnerable region. Here, we compile 316 tree-ring width series from 11 conifer sites in the western Iberian Range. We apply a new standardization method based on the trunk basal area instead of the tree cambial age to develop a regional chronology which preserves high- to low-frequency variability. A new reconstruction for the 1602-2012 period correlates at -0.78 with observational September temperatures with a cumulative mean of the 21 previous months over the 1945-2012 calibration period. The new IR2Tmax reconstruction is spatially representative for the Iberian Peninsula and captures the full range of past Iberian Range temperature variability. Reconstructed long-term temperature variations match reasonably well with solar irradiance changes since warm and cold phases correspond with high and low solar activity, respectively. In addition, some annual temperature downturns coincide with volcanic eruptions with a 3-year lag.

  4. Effects of regional temperature on electric vehicle efficiency, range, and emissions in the United States.

    PubMed

    Yuksel, Tugce; Michalek, Jeremy J

    2015-03-17

    We characterize the effect of regional temperature differences on battery electric vehicle (BEV) efficiency, range, and use-phase power plant CO2 emissions in the U.S. The efficiency of a BEV varies with ambient temperature due to battery efficiency and cabin climate control. We find that annual energy consumption of BEVs can increase by an average of 15% in the Upper Midwest or in the Southwest compared to the Pacific Coast due to temperature differences. Greenhouse gas (GHG) emissions from BEVs vary primarily with marginal regional grid mix, which has three times the GHG intensity in the Upper Midwest as on the Pacific Coast. However, even within a grid region, BEV emissions vary by up to 22% due to spatial and temporal ambient temperature variation and its implications for vehicle efficiency and charging duration and timing. Cold climate regions also encounter days with substantial reduction in EV range: the average range of a Nissan Leaf on the coldest day of the year drops from 70 miles on the Pacific Coast to less than 45 miles in the Upper Midwest. These regional differences are large enough to affect adoption patterns and energy and environmental implications of BEVs relative to alternatives.

  5. Effect of diurnal temperature range on cardiovascular markers in the elderly in Seoul, Korea

    NASA Astrophysics Data System (ADS)

    Lim, Youn-Hee; Kim, Ho; Kim, Jin Hee; Bae, Sanghyuk; Hong, Yun-Chul

    2013-07-01

    While diurnal temperature range (DTR) has been found to be a risk factor for mortality, evaluation of the underlying mechanisms involved in this association are lacking. To explain the association between DTR and health effects, we investigated how cardiovascular markers responded to DTR. Data was obtained from 560 participants who regularly attended a community elderly welfare center located in Seoul, Korea. Data collection was conducted a total of five times over a 3-year period beginning in August, 2008. We examined systolic and diastolic blood pressure (BP), heart rate (HR), and heart rate variability (HRV). Mixed-effects models and generalized additive mixed models were used to assess the relationship of DTR with BP, HR, and HRV. BP was not associated significantly with rapid temperature changes during the day. While HR was associated linearly with increments of DTR, the relationship between DTR and HRV showed nonlinear associations, or the presence of a cutoff around median DTR. At the cutoff level of DTR determined by an inflection point in the graph, standard deviation of normal-to-normal intervals (SDNN) and root mean square successive difference (RMSSD) were peaked, whereas the low frequency:high frequency (LF:HF) ratio was elevated with decreasing DTR below the cutoff level. The study demonstrated that HR increases with increasing temperature range during the day, and that HRV is reduced at small or large DTR, which suggests minimal cardiovascular stress around the median level of temperature range during the day.

  6. Stability of a Crystal Oscillator, Type Si530, Inside and Beyond its Specified Operating Temperature Range

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad

    2011-01-01

    Data acquisition and control systems depend on timing signals for proper operation and required accuracy. These clocked signals are typically provided by some form of an oscillator set to produce a repetitive, defined signal at a given frequency. Crystal oscillators are commonly used because they are less expensive, smaller, and more reliable than other types of oscillators. Because of the inherent characteristics of the crystal, the oscillators exhibit excellent frequency stability within the specified range of operational temperature. In some cases, however, some compensation techniques are adopted to further improve the thermal stability of a crystal oscillator. Very limited data exist on the performance and reliability of commercial-off-the-shelf (COTS) crystal oscillators at temperatures beyond the manufacturer's specified operating temperature range. This information is very crucial if any of these parts were to be used in circuits designed for use in space exploration missions where extreme temperature swings and thermal cycling are encountered. This report presents the results of the work obtained on the operation of Silicon Laboratories crystal oscillator, type Si530, under specified and extreme ambient temperatures.

  7. An improved approach for measuring immersion freezing in large droplets over a wide temperature range

    PubMed Central

    Tobo, Yutaka

    2016-01-01

    Immersion freezing (ice nucleation by particles immersed in supercooled water) is a key process for forming ice in mixed-phase clouds. Immersion freezing experiments with particles in microliter-sized (millimeter-sized) water droplets are often applied to detecting very small numbers of ice nucleating particles (INPs). However, the application of such large droplets remains confined to the detection of INPs active at temperatures much higher than the homogeneous freezing limit, because of artifacts related to freezing of water droplets without added INPs at temperatures of −25 °C or higher on a supporting substrate. Here I report a method for measuring immersion freezing in super-microliter-sized droplets over a wide temperature range. To reduce possible artifacts, droplets are pipetted onto a thin layer of Vaseline and cooled in a clean booth. In the Cryogenic Refrigerator Applied to Freezing Test (CRAFT) system, freezing of pure (Milli-Q) water droplets are limited at temperatures above −30 °C. An intercomparison of various techniques for immersion freezing experiments with reference particles (Snomax and illite NX) demonstrates that despite the use of relatively large droplets, the CRAFT setup allows for evaluating the immersion freezing activity of the particles over almost the entire temperature range (about −30 °C to 0 °C) relevant for mixed-phase cloud formation. PMID:27596247

  8. Experimental Investigation of Soil Thermal Conductivity Over a Wide Temperature Range

    NASA Astrophysics Data System (ADS)

    Nikolaev, Ivan V.; Leong, Wey H.; Rosen, Marc A.

    2013-06-01

    The results are reported of an experimental investigation of the soil thermal conductivity over a wide temperature range, for various water contents and two soil types. The results are particularly important in predictions of underground heat transfer, which require a quantitative understanding of the coupled dependence of the soil thermal conductivity on texture, temperature, and water content. In the research, comprehensive sets of thermal conductivity for Ottawa sand (coarse soil) and Richmond Hill fine sandy loam (medium soil) are experimentally obtained using the guarded hot-plate method, for temperatures ranging from 2° C to 92° C and water contents varying from complete dryness to full saturation. For both soils, the thermal conductivity is observed to vary in three stages with respect to increasing water content: a very minor increase as water content increases to the permanent wilting point, a steep increase as water content further increases to field capacity, and a minor increase (for temperatures less than 72° C) or decrease for (temperatures greater than 72° C) when the field capacity is exceeded. Then, on the basis of gathered datasets, a similar Ke(Sr,T) form of the soil thermal conductivity model by Tarnawski et al. is used to empirically fit the data. The resulted correlations fit the data well with their overall root-relative-mean-square percentage errors of 4.7 % and 6.1 % for Ottawa sand and Richmond Hill fine sandy loam, respectively, and are suitable for most engineering applications.

  9. Thermal stimulated current response in cupric oxide single crystal thin films over a wide temperature range

    NASA Astrophysics Data System (ADS)

    Yang, Kungan; Wu, Shuxiang; Yu, Fengmei; Zhou, Wenqi; Wang, Yunjia; Meng, Meng; Wang, Gaili; Zhang, Yueli; Li, Shuwei

    2017-01-01

    Cupric oxide single crystal thin films (~26 nm) were grown by plasma-assisted molecular beam epitaxy. X-ray diffraction, Raman spectra and in situ reflection high-energy electron diffraction show that the thin films are 2  ×  2 reconstructed with an in-plane compression and out-of-plane stretching. A thermal stimulated current measurement indicates that the electric polarization response is shown in the special 2D cupric oxide single crystal thin film over a wide temperature range from 130 K to near-room temperature. We infer that the abnormal electric response involves the changing of phase transition temperature induced by structure distortion, the spin frustration and the magnetic fluctuation effect of a short-range magnetic order, or the combined action of both of the two factors mentioned above. This work suggests a promising clue for finding new room temperature single phase multiferroics or tuning phase transition temperatures.

  10. Effect of optimizing supply water temperature and air volume on a VAV system

    SciTech Connect

    Karino, Naoki; Shiba, Takashi; Ito, Koichi; Yokoyama, Ryohei

    1999-07-01

    An optimal planning method is proposed for an air conditioning system composed of heat pump chillers and variable air volume (VAV) units. Supply water temperature, supply air volume, and thickness of heat insulation material are determined optimally so as to minimize the annual total cost of the system in consideration of equipment capacities and annual operation for the cooling load varying through a year. Through a numerical study on the system planned for an office building, influences of supply water/air temperatures and air volume on the system are investigated from the viewpoint of long-term economics. As a result, it is shown that the annual energy charge of the optimal VAV system can be reduced considerably in comparison with that of the optimal constant air volume (CAV) system, and that the effect of the energy conservation of the former system is large enough.

  11. Unusually high soil nitrogen oxide emissions influence air quality in a high-temperature agricultural region

    PubMed Central

    Oikawa, P. Y.; Ge, C.; Wang, J.; Eberwein, J. R.; Liang, L. L.; Allsman, L. A.; Grantz, D. A.; Jenerette, G. D.

    2015-01-01

    Fertilized soils have large potential for production of soil nitrogen oxide (NOx=NO+NO2), however these emissions are difficult to predict in high-temperature environments. Understanding these emissions may improve air quality modelling as NOx contributes to formation of tropospheric ozone (O3), a powerful air pollutant. Here we identify the environmental and management factors that regulate soil NOx emissions in a high-temperature agricultural region of California. We also investigate whether soil NOx emissions are capable of influencing regional air quality. We report some of the highest soil NOx emissions ever observed. Emissions vary nonlinearly with fertilization, temperature and soil moisture. We find that a regional air chemistry model often underestimates soil NOx emissions and NOx at the surface and in the troposphere. Adjusting the model to match NOx observations leads to elevated tropospheric O3. Our results suggest management can greatly reduce soil NOx emissions, thereby improving air quality. PMID:26556236

  12. Unusually high soil nitrogen oxide emissions influence air quality in a high-temperature agricultural region.

    PubMed

    Oikawa, P Y; Ge, C; Wang, J; Eberwein, J R; Liang, L L; Allsman, L A; Grantz, D A; Jenerette, G D

    2015-11-10

    Fertilized soils have large potential for production of soil nitrogen oxide (NOx=NO+NO2), however these emissions are difficult to predict in high-temperature environments. Understanding these emissions may improve air quality modelling as NOx contributes to formation of tropospheric ozone (O3), a powerful air pollutant. Here we identify the environmental and management factors that regulate soil NOx emissions in a high-temperature agricultural region of California. We also investigate whether soil NOx emissions are capable of influencing regional air quality. We report some of the highest soil NOx emissions ever observed. Emissions vary nonlinearly with fertilization, temperature and soil moisture. We find that a regional air chemistry model often underestimates soil NOx emissions and NOx at the surface and in the troposphere. Adjusting the model to match NOx observations leads to elevated tropospheric O3. Our results suggest management can greatly reduce soil NOx emissions, thereby improving air quality.

  13. Oxide modified air electrode surface for high temperature electrochemical cells

    DOEpatents

    Singh, Prabhakar; Ruka, Roswell J.

    1992-01-01

    An electrochemical cell is made having a porous cermet electrode (16) and a porous lanthanum manganite electrode (14), with solid oxide electrolyte (15) between them, where the lanthanum manganite surface next to the electrolyte contains a thin discontinuous layer of high surface area cerium oxide and/or praseodymium oxide, preferably as discrete particles (30) in contact with the air electrode and electrolyte.

  14. Measured Performance of a Low Temperature Air Source Heat Pump

    SciTech Connect

    R.K. Johnson

    2013-09-01

    A 4-ton Low Temperature Heat Pump (LTHP) manufactured by Hallowell International was installed in a residence near New Haven, Connecticut and monitored over two winters of operation. After attending to some significant service issues, the heat pump operated as designed. This report should be considered a review of the dual compressor “boosted heat pump” technology. The Low Temperature Heat Pump system operates with four increasing levels of capacity (heat output) as the outdoor temperature drops.

  15. A compound carbon thermometer for the temperature range 0.3-100 K.

    PubMed

    Adolf, A; Djerassi, H; Leszczyszyn, J

    1979-09-01

    A compound carbon thermometer consisting of an abreast connection of a carbon Speer resistor and a carbon Allen-Bradley resistor was tested in the temperature interval 0.3-100 K, an interval which generally requires two independent resistors to be covered. The characteristics, sensitivity, and analytical handling of the resistance versus temperature data are discussed and compared with the corresponding behavior of other thermometers. The satisfactory performance of the compound carbon device contributes to the extension of wide-range thermometry to 0.3 K.

  16. Improved Temperature Sounding and Quality Control Methodology Using AIRS/AMSU Data: The AIRS Science Team Version 5 Retrieval Algorithm

    NASA Technical Reports Server (NTRS)

    Susskind, Joel; Blaisdell, John M.; Iredell, Lena; Keita, Fricky

    2009-01-01

    This paper describes the AIRS Science Team Version 5 retrieval algorithm in terms of its three most significant improvements over the methodology used in the AIRS Science Team Version 4 retrieval algorithm. Improved physics in Version 5 allows for use of AIRS clear column radiances in the entire 4.3 micron CO2 absorption band in the retrieval of temperature profiles T(p) during both day and night. Tropospheric sounding 15 micron CO2 observations are now used primarily in the generation of clear column radiances .R(sub i) for all channels. This new approach allows for the generation of more accurate values of .R(sub i) and T(p) under most cloud conditions. Secondly, Version 5 contains a new methodology to provide accurate case-by-case error estimates for retrieved geophysical parameters and for channel-by-channel clear column radiances. Thresholds of these error estimates are used in a new approach for Quality Control. Finally, Version 5 also contains for the first time an approach to provide AIRS soundings in partially cloudy conditions that does not require use of any microwave data. This new AIRS Only sounding methodology, referred to as AIRS Version 5 AO, was developed as a backup to AIRS Version 5 should the AMSU-A instrument fail. Results are shown comparing the relative performance of the AIRS Version 4, Version 5, and Version 5 AO for the single day, January 25, 2003. The Goddard DISC is now generating and distributing products derived using the AIRS Science Team Version 5 retrieval algorithm. This paper also described the Quality Control flags contained in the DISC AIRS/AMSU retrieval products and their intended use for scientific research purposes.

  17. Estimation of Surface Air Temperature Over Central and Eastern Eurasia from MODIS Land Surface Temperature

    NASA Technical Reports Server (NTRS)

    Shen, Suhung; Leptoukh, Gregory G.

    2011-01-01

    Surface air temperature (T(sub a)) is a critical variable in the energy and water cycle of the Earth.atmosphere system and is a key input element for hydrology and land surface models. This is a preliminary study to evaluate estimation of T(sub a) from satellite remotely sensed land surface temperature (T(sub s)) by using MODIS-Terra data over two Eurasia regions: northern China and fUSSR. High correlations are observed in both regions between station-measured T(sub a) and MODIS T(sub s). The relationships between the maximum T(sub a) and daytime T(sub s) depend significantly on land cover types, but the minimum T(sub a) and nighttime T(sub s) have little dependence on the land cover types. The largest difference between maximum T(sub a) and daytime T(sub s) appears over the barren and sparsely vegetated area during the summer time. Using a linear regression method, the daily maximum T(sub a) were estimated from 1 km resolution MODIS T(sub s) under clear-sky conditions with coefficients calculated based on land cover types, while the minimum T(sub a) were estimated without considering land cover types. The uncertainty, mean absolute error (MAE), of the estimated maximum T(sub a) varies from 2.4 C over closed shrublands to 3.2 C over grasslands, and the MAE of the estimated minimum Ta is about 3.0 C.

  18. Preliminary verification of instantaneous air temperature estimation for clear sky conditions based on SEBAL

    NASA Astrophysics Data System (ADS)

    Zhu, Shanyou; Zhou, Chuxuan; Zhang, Guixin; Zhang, Hailong; Hua, Junwei

    2017-02-01

    Spatially distributed near surface air temperature at the height of 2 m is an important input parameter for the land surface models. It is of great significance in both theoretical research and practical applications to retrieve instantaneous air temperature data from remote sensing observations. An approach based on Surface Energy Balance Algorithm for Land (SEBAL) to retrieve air temperature under clear sky conditions is presented. Taking the meteorological measurement data at one station as the reference and remotely sensed data as the model input, the research estimates the air temperature by using an iterative computation. The method was applied to the area of Jiangsu province for nine scenes by using MODIS data products, as well as part of Fujian province, China based on four scenes of Landsat 8 imagery. Comparing the air temperature estimated from the proposed method with that of the meteorological station measurement, results show that the root mean square error is 1.7 and 2.6 °C at 1000 and 30 m spatial resolution respectively. Sensitivity analysis of influencing factors reveals that land surface temperature is the most sensitive to the estimation precision. Research results indicate that the method has great potentiality to be used to estimate instantaneous air temperature distribution under clear sky conditions.

  19. A Review of the Thermodynamic, Transport, and Chemical Reaction Rate Properties of High-temperature Air

    NASA Technical Reports Server (NTRS)

    Hansen, C Frederick; Heims, Steve P

    1958-01-01

    Thermodynamic and transport properties of high temperature air, and the reaction rates for the important chemical processes which occur in air, are reviewed. Semiempirical, analytic expressions are presented for thermodynamic and transport properties of air. Examples are given illustrating the use of these properties to evaluate (1) equilibrium conditions following shock waves, (2) stagnation region heat flux to a blunt high-speed body, and (3) some chemical relaxation lengths in stagnation region flow.

  20. Assessing the Potential of the AIRS Retrieved Surface Temperature for 6-Hour Average Temperature Forecast in River Forecast Centers

    NASA Astrophysics Data System (ADS)

    Ding, F.; Theobald, M.; Vollmer, B.; Savtchenko, A. K.; Hearty, T. J.; Esfandiari, A. E.

    2012-12-01

    Producing timely and accurate water forecast and information is the mission of National Weather Service River Forecast Centers (NWS RFCs) of National Oceanic and Atmospheric Administration (NOAA). The river forecast system in RFCs requires average surface temperature in the fixed 6-hour period 000-0600, 0600-1200, 1200-1800, and 1200-0000 UTC. The current logic of RFC temperature forecast relies on ingest of point values of daytime maximum and nighttime minimum temperature. Meanwhile, the mean temperature for the 6-hour period is estimated from a weighted average of daytime maximum and nighttime minimum temperature. The Atmospheric Infrared Sounder (AIRS) in the first high spectral resolution infrared sounder on board the Aqua satellite which was launched in May 2002 and follows a Sun-synchronous polar orbit. It is aimed to produce high resolution atmospheric profile and surface atmospheric parameters. As Aqua crosses the equator at about 1330 and 0130 local time, the AIRS retrieved surface temperature may represent daytime maximum and nighttime minimum value. Comparing to point observation from surface weather stations which are often sparse over the less-populated area and are unevenly distributed, satellite may obtain better area averaged observation. This test study assesses the potential of using AIRS retrieved surface temperature to forecast 6-hour average temperature for NWS RFCs. The California Nevada RFC is selected due to the poor coverage of surface observation in the mountainous region and spring snow melting. The study focuses on the March to May spring season when water from snowpack melting often plays important role in flood. AIRS retrieved temperature and surface weather station data set will be used to derive statistical weighting coefficient for 6-hour average temperature forecast. The resulting forecast biases and errors will be the main indicators of the potential usage. All study results will be presented in the meeting.

  1. Biodiesel and Cold Temperature Effects on Speciated Mobile Source Air Toxics from Modern Diesel Trucks

    EPA Science Inventory

    Speciated volatile organic compounds (VOCs) with a particular focus on mobile source air toxics (MSATs) were measured in diesel exhaust from three heavy-duty trucks equipped with modern aftertreatment technologies. Emissions testing was conducted on a temperature controlled chass...

  2. Biodiesel and Cold Temperature Effect on Speciated Mobile Source Air Toxics from Modern Diesel Trucks

    EPA Science Inventory

    Speciated volatile organic compounds (VOCs) with a particular focus on mobile source air toxics (MSATs) were measured in diesel exhaust from three heavy-duty trucks equipped with modern aftertreatment technologies. Emissions testing was conducted on a temperature controlled chass...

  3. High-temperature stabilization by air of a pyrophoric catalyst for the synthesis of ammonia

    SciTech Connect

    Krylova, A.V.; Ustimenko, G.A.

    1982-12-01

    The reaction of a catalyst for the synthesis of ammonia with air at 480 to 520/sup 0/C leads to the formation on the surface of a thin protective oxide structure that eliminates its pyrophoric character. High-temperature stabilization by air is a considerably faster process than passivation and leads to the production of catalysts with increased resistance to oxidation.

  4. Temperature and Humidity Independent Control Research on Ground Source Heat Pump Air Conditioning System

    NASA Astrophysics Data System (ADS)

    Chen, G.; Wang, L. L.

    Taking green demonstration center building air conditioning system as an example, this paper presents the temperature and humidity independent control system combined with ground source heat pump system, emphasis on the design of dry terminal device system, fresh air system and ground source heat pump system.

  5. Improving Forecast Skill by Assimilation of Quality-controlled AIRS Temperature Retrievals under Partially Cloudy Conditions

    NASA Technical Reports Server (NTRS)

    Reale, O.; Susskind, J.; Rosenberg, R.; Brin, E.; Riishojgaard, L.; Liu, E.; Terry, J.; Jusem, J. C.

    2007-01-01

    The National Aeronautics and Space Administration (NASA) Atmospheric Infrared Sounder (AIRS) on board the Aqua satellite has been long recognized as an important contributor towards the improvement of weather forecasts. At this time only a small fraction of the total data produced by AIRS is being used by operational weather systems. In fact, in addition to effects of thinning and quality control, the only AIRS data assimilated are radiance observations of channels unaffected by clouds. Observations in mid-lower tropospheric sounding AIRS channels are assimilated primarily under completely clear-sky conditions, thus imposing a very severe limitation on the horizontal distribution of the AIRS-derived information. In this work it is shown that the ability to derive accurate temperature profiles from AIRS observations in partially cloud-contaminated areas can be utilized to further improve the impact of AIRS observations in a global model and forecasting system. The analyses produced by assimilating AIRS temperature profiles obtained under partial cloud cover result in a substantially colder representation of the northern hemisphere lower midtroposphere at higher latitudes. This temperature difference has a strong impact, through hydrostatic adjustment, in the midtropospheric geopotential heights, which causes a different representation of the polar vortex especially over northeastern Siberia and Alaska. The AIRS-induced anomaly propagates through the model's dynamics producing improved 5-day forecasts.

  6. Improving forecast skill by assimilation of quality-controlled AIRS temperature retrievals under partially cloudy conditions

    NASA Astrophysics Data System (ADS)

    Reale, O.; Susskind, J.; Rosenberg, R.; Brin, E.; Liu, E.; Riishojgaard, L. P.; Terry, J.; Jusem, J. C.

    2008-04-01

    The National Aeronautics and Space Administration (NASA) Atmospheric Infrared Sounder (AIRS) on board the Aqua satellite is now recognized as an important contributor towards the improvement of weather forecasts. At this time only a small fraction of the total data produced by AIRS is being used by operational weather systems. In fact, in addition to effects of thinning and quality control, the only AIRS data assimilated are radiance observations of channels unaffected by clouds. Observations in mid-lower tropospheric sounding AIRS channels are assimilated primarily under completely clear-sky conditions, thus imposing a very severe limitation on the horizontal distribution of the AIRS-derived information. In this work it is shown that the ability to derive accurate temperature profiles from AIRS observations in partially cloud-contaminated areas can be utilized to further improve the impact of AIRS observations in a global model and forecasting system. The analyses produced by assimilating AIRS temperature profiles obtained under partial cloud cover result in a substantially colder representation of the northern hemisphere lower midtroposphere at higher latitudes. This temperature difference has a strong impact, through hydrostatic adjustment, in the midtropospheric geopotential heights, which causes a different representation of the polar vortex especially over northeastern Siberia and Alaska. The AIRS-induced anomaly propagates through the model's dynamics producing improved 5-day forecasts.

  7. Modelling the impact of room temperature on concentrations of polychlorinated biphenyls (PCBs) in indoor air.

    PubMed

    Lyng, Nadja Lynge; Clausen, Per Axel; Lundsgaard, Claus; Andersen, Helle Vibeke

    2016-02-01

    Buildings contaminated with polychlorinated biphenyls (PCBs) are a health concern for the building occupants. Inhalation exposure is linked to indoor air concentrations of PCBs, which are known to be affected by indoor temperatures. In this study, a highly PCB contaminated room was heated to six temperature levels between 20 and 30 C, i.e. within the normal fluctuation of indoor temperatures, while the air exchange rate was constant. The steady-state air concentrations of seven PCBs were determined at each temperature level. A model based on Clausius-Clapeyron equation, ln(P) = -ΔH/RT + a(0), where changes in steady-state air concentrations in relation to temperature, was tested. The model was valid for PCB-28, PCB-52 and PCB-101; the four other congeners were sporadic or non-detected. For each congener, the model described a large proportion (R(2)>94%) of the variation in indoor air PCB levels. The results showed that one measured concentration of PCB at a known steady-state temperature can be used to predict the steady-state concentrations at other temperatures under circumstances where e.g. direct sunlight does not influence temperatures and the air exchange rate is constant. The model was also tested on field data from a PCB remediation case in an apartment in another contaminated building complex where PCB concentrations and temperature were measured simultaneously and regularly throughout one year. The model fitted relatively well with the regression of measured PCB air concentrations, ln(P) vs. 1/T, at varying temperature between 16.3 and 28.2 °C, even though the measurements were carried out under uncontrolled environmental condition.

  8. Factors affecting temperature variation and habitat use in free-ranging diamondback terrapins.

    PubMed

    Akins, C D; Ruder, C D; Price, S J; Harden, L A; Gibbons, J W; Dorcas, M E

    2014-08-01

    Measuring the thermal conditions of aquatic reptiles with temperature dataloggers is a cost-effective way to study their behavior and habitat use. Temperature dataloggers are a particularly useful and informative approach to studying organisms such as the estuarine diamondback terrapin (Malaclemys terrapin) that inhabits a dynamic environment often inaccessible to researchers. We used carapace-mounted dataloggers to measure hourly carapace temperature (Tc) of free-ranging terrapins in South Carolina from October 2007 to 2008 to examine the effects of month, sex, creek site, and tide on Tc and to determine the effects of month, sex, and time of day on terrapin basking frequency. Simultaneous measurements of environmental temperatures (Te; shallow mud, deep mud, water) allowed us to make inferences about terrapin microhabitat use. Terrapin Tc differed significantly among months and creek and between sexes. Terrapin microhabitat use also varied monthly, with shallow mud temperature being the best predictor of Tc November-March and water temperature being the best predictor of Tc April-October. Terrapins basked most frequently in spring and fall and males basked more frequently than females. Our study contributes to a fuller understanding of terrapin thermal biology and provides support for using dataloggers to investigate behavior and habitat use of aquatic ectotherms inhabiting dynamic environments.

  9. Feeding behaviour of free-ranging penguins determined by oesophageal temperature.

    PubMed

    Charrassin, J B; Kato, A; Handrich, Y; Sato, K; Naito, Y; Ancel, A; Bost, C A; Gauthier-Clerc, M; Ropert-Coudert, Y; Le Maho, Y

    2001-01-22

    Sea birds play a major role in marine food webs, and it is important to determine when and how much they feed at sea. A major advance has been made by using the drop in stomach temperature after ingestion of ectothermic prey. This method is less sensitive when birds eat small prey or when the stomach is full. Moreover, in diving birds, independently of food ingestion, there are fluctuations in the lower abdominal temperature during the dives. Using oesophageal temperature, we present here a new method for detecting the timing of prey ingestion in free-ranging sea birds, and, to our knowledge, report the first data obtained on king penguins (Aptenodytes patagonicus). In birds ashore, which were hand-fed 2-15 g pieces of fish, all meal ingestions were detected with a sensor in the upper oesophagus. Detection was poorer with sensors at increasing distances from the beak. At sea, slow temperature drops in the upper oesophagus and stomach characterized a diving effect per se. For the upper oesophagus only, abrupt temperature variations were superimposed, therefore indicating prey ingestions. We determined the depths at which these occurred. Combining the changes in oesophageal temperatures of marine predators with their diving pattern opens new perspectives for understanding their foraging strategy, and, after validation with concurrent applications of classical techniques of prey survey, for assessing the distribution of their prey.

  10. Computer prediction of human thermoregulatory and temperature responses to a wide range of environmental conditions

    NASA Astrophysics Data System (ADS)

    Fiala, D.; Lomas, K. J.; Stohrer, M.

    A mathematical model for predicting human thermal and regulatory responses in cold, cool, neutral, warm, and hot environments has been developed and validated. The multi-segmental passive system, which models the dynamic heat transport within the body and the heat exchange between body parts and the environment, is discussed elsewhere. This paper is concerned with the development of the active system, which simulates the regulatory responses of shivering, sweating, and peripheral vasomotion of unacclimatised subjects. Following a comprehensive literature review, 26 independent experiments were selected that were designed to provoke each of these responses in different circumstances. Regression analysis revealed that skin and head core temperature affect regulatory responses in a non-linear fashion. A further signal, i.e. the rate of change of the mean skin temperature weighted by the skin temperature error signal, was identified as governing the dynamics of thermoregulatory processes in the cold. Verification and validation work was carried out using experimental data obtained from 90 exposures covering a range of steady and transient ambient temperatures between 5°C and 50°C and exercise intensities between 46 W/m2 and 600 W/m2. Good general agreement with measured data was obtained for regulatory responses, internal temperatures, and the mean and local skin temperatures of unacclimatised humans for the whole spectrum of climatic conditions and for different activity levels.

  11. A lithium-ion capacitor model working on a wide temperature range

    NASA Astrophysics Data System (ADS)

    Barcellona, S.; Piegari, L.

    2017-02-01

    Energy storage systems are spreading both in stationary and transport applications. Among innovative storage devices, lithium ion capacitors (LiCs) are very interesting. They combine the advantages of both traditional electric double layer capacitors (EDLCs) and lithium ion batteries (LiBs). The behavior of this device is much more similar to ELDCs than to batteries. For this reason, several models developed for traditional ELDCs were extended to LiCs. Anyway, at low temperatures LiCs behavior is quite different from ELDCs and it is more similar to a LiB. Consequently, EDLC models works fine at room temperature but give worse results at low temperatures. This paper proposes a new electric model that, overcoming this issue, is a valid solution in a wide temperature range. Based on only five parameters, depending on polarization voltage and temperature, the proposed model is very simple to be implemented. Its accuracy is verified through experimental tests. From the reported results, it is also shown that, at very low temperatures, the dependence of the resistance from the current has to be taken into account.

  12. 33 CFR 334.630 - Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base...″, longitude 82°33′02.44″; and thence to a point on the shore line of MacDill Air Force Base at......

  13. 33 CFR 334.630 - Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base...″, longitude 82°33′02.44″; and thence to a point on the shore line of MacDill Air Force Base at......

  14. 33 CFR 334.630 - Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base...″, longitude 82°33′02.44″; and thence to a point on the shore line of MacDill Air Force Base at......

  15. 33 CFR 334.630 - Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base...″, longitude 82°33′02.44″; and thence to a point on the shore line of MacDill Air Force Base at......

  16. 33 CFR 334.630 - Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base...″, longitude 82°33′02.44″; and thence to a point on the shore line of MacDill Air Force Base at......

  17. Increasing influence of air temperature on upper Colorado River streamflow

    USGS Publications Warehouse

    Woodhouse, Connie A.; Pederson, Gregory T.; Morino, Kiyomi; McAfee, Stephanie A.; McCabe, Gregory

    2016-01-01

    This empirical study examines the influence of precipitation, temperature, and antecedent soil moisture on upper Colorado River basin (UCRB) water year streamflow over the past century. While cool season precipitation explains most of the variability in annual flows, temperature appears to be highly influential under certain conditions, with the role of antecedent fall soil moisture less clear. In both wet and dry years, when flow is substantially different than expected given precipitation, these factors can modulate the dominant precipitation influence on streamflow. Different combinations of temperature, precipitation, and soil moisture can result in flow deficits of similar magnitude, but recent droughts have been amplified by warmer temperatures that exacerbate the effects of relatively modest precipitation deficits. Since 1988, a marked increase in the frequency of warm years with lower flows than expected, given precipitation, suggests continued warming temperatures will be an increasingly important influence in reducing future UCRB water supplies.

  18. Increasing influence of air temperature on upper Colorado River streamflow

    NASA Astrophysics Data System (ADS)

    Woodhouse, Connie A.; Pederson, Gregory T.; Morino, Kiyomi; McAfee, Stephanie A.; McCabe, Gregory J.

    2016-03-01

    This empirical study examines the influence of precipitation, temperature, and antecedent soil moisture on upper Colorado River basin (UCRB) water year streamflow over the past century. While cool season precipitation explains most of the variability in annual flows, temperature appears to be highly influential under certain conditions, with the role of antecedent fall soil moisture less clear. In both wet and dry years, when flow is substantially different than expected given precipitation, these factors can modulate the dominant precipitation influence on streamflow. Different combinations of temperature, precipitation, and soil moisture can result in flow deficits of similar magnitude, but recent droughts have been amplified by warmer temperatures that exacerbate the effects of relatively modest precipitation deficits. Since 1988, a marked increase in the frequency of warm years with lower flows than expected, given precipitation, suggests continued warming temperatures will be an increasingly important influence in reducing future UCRB water supplies.

  19. Two-phase working fluids for the temperature range of 50 to 350 deg, phase 2

    NASA Technical Reports Server (NTRS)

    Saaski, E. W.; Hartl, J. H.

    1980-01-01

    Several two phase heat transfer fluids were tested in aluminum and carbon steel reflux capsules for over 25,000 hours at temperatures up to 300 C. Several fluids showed very good stability and would be useful for long duration heat transfer applications over the range 100 to 350 C. Instrumentation for the measurement of surface tension and viscosity were constructed for use with heat transfer fluids over the temperature range 0 to 300 C and with pressures from 0 to 10 atmospheres. The surface tension measuring device constructed requires less than a 1.0 cc sample and displays an accuracy of about 5 percent in preliminary tests, while the viscometer constructed for this program requires a 0.05 cc sample and shows an accuracy of about 5 percent in initial tests.

  20. Temperature-dependent alterations in host use drive rapid range expansion in a butterfly.

    PubMed

    Pateman, Rachel M; Hill, Jane K; Roy, David B; Fox, Richard; Thomas, Chris D

    2012-05-25

    Responses of species to climate change are extremely variable, perhaps because of climate-related changes to interactions among species. We show that temperature-related changes in the dependence of the butterfly Aricia agestis on different larval host plants have facilitated rapid range expansion. Historically, the butterfly was largely restricted to a single plant species, Helianthemum nummularium, but recent warmer conditions have enabled the butterfly to increasingly use the more widespread plant species Geranium molle. This has resulted in a substantial increase in available habitat and rapid range expansion by the butterfly (79 kilometers northward in Britain in 20 years). Interactions among species are often seen as constraints on species' responses to climate change, but we show that temperature-dependent changes to interspecific interactions can also facilitate change.

  1. V-structures of ethylene glycol and monoethanolamine in the temperature range of the liquid phase

    NASA Astrophysics Data System (ADS)

    Balabaev, N. K.; Rodnikova, M. N.; Solonina, I. A.; Shirokova, E. V.; Sirotkin, D. A.

    2017-01-01

    Vibration-averaged V-structures for liquid ethylene glycol (EG) and monoethanolamine (MEA) are found in the temperature range of the solvents' liquid phase by means of molecular dynamics. The obtained V-structures' characteristics are compared to X-ray diffraction data on the crystalline phases of these compounds. Good agreement between theoretical and experimental data is observed. The V-structures are compared to that of water.

  2. Artificial Temperature Anisotropy of Crystals in X-Ray Frequency Range

    SciTech Connect

    Mkrtchyan, Vahram P.; Gasparyan, Laura G.; Balyan, Minas K.

    2010-04-06

    The effect of artificial temperature anisotropy of crystals in X-ray frequency range was observed for the first time and an effort to theoretically interpret this effect in Bragg-Laue diffraction case was made. It was established that an isotropic crystal optically turns into an artificially anisotropic one with optical axis along the direction of applied external influence as a symmetry axis, giving rise to the double refraction.

  3. Two-Phase Working Fluids for the Temperature Range 50 to 350 C

    NASA Technical Reports Server (NTRS)

    Saaski, E. W.; Owzarski, P. C.

    1977-01-01

    The decomposition and corrosion of two-phase heat transfer liquids and metal envelopes have been investigated on the basis of molecular bond strengths and chemical thermodynamics. Potentially stable heat transfer fluids for the temperature range 100 C to 350 C have been identified, and reflux heat pipes tests initiated with 10 fluids and carbon steel and aluminum envelopes to experimentally establish corrosion behavior and noncondensable gas generation rates.

  4. Rate constants for chemical reactions in high-temperature nonequilibrium air

    NASA Technical Reports Server (NTRS)

    Jaffe, R. L.

    1986-01-01

    In the nonequilibrium atmospheric chemistry regime that will be encountered by the proposed Aeroassisted Orbital Transfer Vehicle in the upper atmosphere, where air density is too low for thermal and chemical equilibrium to be maintained, the detailed high temperature air chemistry plays a critical role in defining radiative and convective heating loads. Although vibrational and electronic temperatures remain low (less than 15,000 K), rotational and translational temperatures may reach 50,000 K. Attention is presently given to the effects of multiple temperatures on the magnitudes of various chemical reaction rate constants, for the cases of both bimolecular exchange reactions and collisional excitation and dissociation reactions.

  5. Emperor penguin body surfaces cool below air temperature

    PubMed Central

    McCafferty, D. J.; Gilbert, C.; Thierry, A.-M.; Currie, J.; Le Maho, Y.; Ancel, A.

    2013-01-01

    Emperor penguins Aptenodytes forsteri are able to survive the harsh Antarctic climate because of specialized anatomical, physiological and behavioural adaptations for minimizing heat loss. Heat transfer theory predicts that metabolic heat loss in this species will mostly depend on radiative and convective cooling. To examine this, thermal imaging of emperor penguins was undertaken at the breeding colony of Pointe Géologie in Terre Adélie (66°40′ S 140° 01′ E), Antarctica in June 2008. During clear sky conditions, most outer surfaces of the body were colder than surrounding sub-zero air owing to radiative cooling. In these conditions, the feather surface will paradoxically gain heat by convection from surrounding air. However, owing to the low thermal conductivity of plumage any heat transfer to the skin surface will be negligible. Future thermal imaging studies are likely to yield further insights into the adaptations of this species to the Antarctic climate. PMID:23466479

  6. Study of special ceramics with a dilatometer in the temperature range 25 2000°C

    NASA Astrophysics Data System (ADS)

    Kaisersberger, E.; Kelly, J.

    1989-03-01

    Many properties of special ceramic materials, often closely related, such as sintering temperature, shrinkage in firing, mineral reaction, and strength can be studied with thermal analysis. Also the influence of type, structure, and preparation of raw materials and, of plasticizers and binding materials for forming and compressing, as well as the compatibility with protective coatings (glazes, varnishes, metal films), are investigated by thermal analysis. The development of a new dilatometer for the temperature range 25 2000°C with maximum heating rates of 20 K·min-1 and sample sizes 25 50 mm in length and 6 12 mm in diameter for measurements in an argon atmosphere and vacuum has opened up new horizons. Sintering studies at high temperatures are described.

  7. Assessing recent air-sea freshwater flux changes using a surface temperature-salinity space framework

    NASA Astrophysics Data System (ADS)

    Grist, Jeremy P.; Josey, Simon A.; Zika, Jan D.; Evans, Dafydd Gwyn; Skliris, Nikolaos

    2016-12-01

    A novel assessment of recent changes in air-sea freshwater fluxes has been conducted using a surface temperature-salinity framework applied to four atmospheric reanalyses. Viewed in the T-S space of the ocean surface, the complex pattern of the longitude-latitude space mean global Precipitation minus Evaporation (PME) reduces to three distinct regions. The analysis is conducted for the period 1979-2007 for which there is most evidence for a broadening of the (atmospheric) tropical belt. All four of the reanalyses display an increase in strength of the water cycle. The range of increase is between 2% and 30% over the period analyzed, with an average of 14%. Considering the average across the reanalyses, the water cycle changes are dominated by changes in tropical as opposed to mid-high latitude precipitation. The increases in the water cycle strength, are consistent in sign, but larger than in a 1% greenhouse gas run of the HadGEM3 climate model. In the model a shift of the precipitation/evaporation cells to higher temperatures is more evident, due to the much stronger global warming signal. The observed changes in freshwater fluxes appear to be reflected in changes in the T-S distribution of the Global Ocean. Specifically, across the diverse range of atmospheric reanalyses considered here, there was an acceleration of the hydrological cycle during 1979-2007 which led to a broadening of the ocean's salinity distribution. Finally, although the reanalyses indicate that the warm temperature tropical precipitation dominated water cycle change, ocean observations suggest that ocean processes redistributed the freshening to lower ocean temperatures.

  8. Reassessing changes in diurnal temperature range: A new data set and characterization of data biases

    NASA Astrophysics Data System (ADS)

    Thorne, P. W.; Menne, M. J.; Williams, C. N.; Rennie, J. J.; Lawrimore, J. H.; Vose, R. S.; Peterson, T. C.; Durre, I.; Davy, R.; Esau, I.; Klein-Tank, A. M. G.; Merlone, A.

    2016-05-01

    It has been a decade since changes in diurnal temperature range (DTR) globally have been assessed in a stand-alone data analysis. The present study takes advantage of substantively improved basic data holdings arising from the International Surface Temperature Initiative's databank effort and applies the National Centers for Environmental Information's automated pairwise homogeneity assessment algorithm to reassess DTR records. It is found that breakpoints are more prevalent in DTR than other temperature elements and that the resulting adjustments have a broader distribution. This strongly implies that there is an overarching tendency, across the global meteorological networks, for nonclimatic artifacts to impart either random or anticorrelated rather than correlated biases in maximum and minimum temperature series. Future homogenization efforts would likely benefit from simultaneous consideration of DTR and maximum and minimum temperatures, in addition to average temperatures. Estimates of change in DTR are relatively insensitive to whether adjustments are calculated directly or inferred from adjustments returned for the maximum and minimum temperature series. The homogenized series exhibit a reduction in DTR since the midtwentieth century globally (-0.044 K/decade). Adjustments serve to approximately halve the long-term global reduction in DTR in the basic "raw" data. Most of the estimated DTR reduction occurred over 1960-1980. In several regions DTR has apparently increased over 1979-2012, while globally it has exhibited very little change (-0.016 K/decade). Estimated changes in DTR are an order of magnitude smaller than in maximum and minimum temperatures, which have both been increasing rapidly on multidecadal timescales (0.186 K/decade and 0.236 K/decade, respectively, since the midtwentieth century).

  9. SiC JFET Transistor Circuit Model for Extreme Temperature Range

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G.

    2008-01-01

    A technique for simulating extreme-temperature operation of integrated circuits that incorporate silicon carbide (SiC) junction field-effect transistors (JFETs) has been developed. The technique involves modification of NGSPICE, which is an open-source version of the popular Simulation Program with Integrated Circuit Emphasis (SPICE) general-purpose analog-integrated-circuit-simulating software. NGSPICE in its unmodified form is used for simulating and designing circuits made from silicon-based transistors that operate at or near room temperature. Two rapid modifications of NGSPICE source code enable SiC JFETs to be simulated to 500 C using the well-known Level 1 model for silicon metal oxide semiconductor field-effect transistors (MOSFETs). First, the default value of the MOSFET surface potential must be changed. In the unmodified source code, this parameter has a value of 0.6, which corresponds to slightly more than half the bandgap of silicon. In NGSPICE modified to simulate SiC JFETs, this parameter is changed to a value of 1.6, corresponding to slightly more than half the bandgap of SiC. The second modification consists of changing the temperature dependence of MOSFET transconductance and saturation parameters. The unmodified NGSPICE source code implements a T(sup -1.5) temperature dependence for these parameters. In order to mimic the temperature behavior of experimental SiC JFETs, a T(sup -1.3) temperature dependence must be implemented in the NGSPICE source code. Following these two simple modifications, the Level 1 MOSFET model of the NGSPICE circuit simulation program reasonably approximates the measured high-temperature behavior of experimental SiC JFETs properly operated with zero or reverse bias applied to the gate terminal. Modification of additional silicon parameters in the NGSPICE source code was not necessary to model experimental SiC JFET current-voltage performance across the entire temperature range from 25 to 500 C.

  10. Cavity Ring Down Absorption of Oxygen in Air as a Temperature Sensor

    NASA Astrophysics Data System (ADS)

    Manzanares, Carlos; Nyaupane, Parashu R.

    2016-06-01

    The A-band of oxygen has been measured at low resolution at temperatures between 90 K and 373 K using the phase shift cavity ring down (PS-CRD) technique. For temperatures between 90 K and 295 K, the PS-CRD technique presented here involves an optical cavity attached to a cryostat. The static cell and mirrors of the optical cavity are all inside a vacuum chamber at the same temperature of the cryostat. The temperature of the cell can be changed between 77 K and 295 K. For temperatures above 295 K, a hollow glass cylindrical tube without windows has been inserted inside an optical cavity to measure the temperature of air flowing through the tube. The cavity consists of two highly reflective mirrors which are mounted parallel to each other and separated by a distance of 93 cm. In this experiment, air is passed through a heated tube. The temperature of the air flowing through the tube is determined by measuring the intensity of the oxygen absorption as a function of the wavenumber. The A-band of oxygen is measured between 298 K and 373 K, with several air flow rates. Accuracy of the temperature measurement is determined by comparing the calculated temperature from the spectra with the temperature obtained from a calibrated thermocouple inserted at the center of the tube.

  11. Long-range energy transport in single supramolecular nanofibres at room temperature

    NASA Astrophysics Data System (ADS)

    Haedler, Andreas T.; Kreger, Klaus; Issac, Abey; Wittmann, Bernd; Kivala, Milan; Hammer, Natalie; Köhler, Jürgen; Schmidt, Hans-Werner; Hildner, Richard

    2015-07-01

    Efficient transport of excitation energy over long distances is a key process in light-harvesting systems, as well as in molecular electronics. However, in synthetic disordered organic materials, the exciton diffusion length is typically only around 10 nanometres (refs 4, 5), or about 50 nanometres in exceptional cases, a distance that is largely determined by the probability laws of incoherent exciton hopping. Only for highly ordered organic systems has the transport of excitation energy over macroscopic distances been reported--for example, for triplet excitons in anthracene single crystals at room temperature, as well as along single polydiacetylene chains embedded in their monomer crystalline matrix at cryogenic temperatures (at 10 kelvin, or -263 degrees Celsius). For supramolecular nanostructures, uniaxial long-range transport has not been demonstrated at room temperature. Here we show that individual self-assembled nanofibres with molecular-scale diameter efficiently transport singlet excitons at ambient conditions over more than four micrometres, a distance that is limited only by the fibre length. Our data suggest that this remarkable long-range transport is predominantly coherent. Such coherent long-range transport is achieved by one-dimensional self-assembly of supramolecular building blocks, based on carbonyl-bridged triarylamines, into well defined H-type aggregates (in which individual monomers are aligned cofacially) with substantial electronic interactions. These findings may facilitate the development of organic nanophotonic devices and quantum information technology.

  12. Long-range energy transport in single supramolecular nanofibres at room temperature.

    PubMed

    Haedler, Andreas T; Kreger, Klaus; Issac, Abey; Wittmann, Bernd; Kivala, Milan; Hammer, Natalie; Köhler, Jürgen; Schmidt, Hans-Werner; Hildner, Richard

    2015-07-09

    Efficient transport of excitation energy over long distances is a key process in light-harvesting systems, as well as in molecular electronics. However, in synthetic disordered organic materials, the exciton diffusion length is typically only around 10 nanometres (refs 4, 5), or about 50 nanometres in exceptional cases, a distance that is largely determined by the probability laws of incoherent exciton hopping. Only for highly ordered organic systems has the transport of excitation energy over macroscopic distances been reported--for example, for triplet excitons in anthracene single crystals at room temperature, as well as along single polydiacetylene chains embedded in their monomer crystalline matrix at cryogenic temperatures (at 10 kelvin, or -263 degrees Celsius). For supramolecular nanostructures, uniaxial long-range transport has not been demonstrated at room temperature. Here we show that individual self-assembled nanofibres with molecular-scale diameter efficiently transport singlet excitons at ambient conditions over more than four micrometres, a distance that is limited only by the fibre length. Our data suggest that this remarkable long-range transport is predominantly coherent. Such coherent long-range transport is achieved by one-dimensional self-assembly of supramolecular building blocks, based on carbonyl-bridged triarylamines, into well defined H-type aggregates (in which individual monomers are aligned cofacially) with substantial electronic interactions. These findings may facilitate the development of organic nanophotonic devices and quantum information technology.

  13. VCSEL based transmitter module for automotive temperature range between -55° C and +125° C

    NASA Astrophysics Data System (ADS)

    Poferl, Stefan G.; Krieg, Marcel; Hocky, Oliver; Zeeb, Eberhard

    2003-04-01

    Robust, high speed optical data bus systems are increasingly required in automobiles, not only for entertainment applications within the passenger compartment but also for engine management systems and safety sensor networks. Optoelectronic components and modules intended to be used in cars have to withstand harsh environmental conditions, e.g. they have to be operational within a wide temperature range of up to - 55 °C to +1 25 °C for several thousand hours and at the same time they have to be of very low-cost. In this paper we describe a 500 MBit/s transmitter module based on a commercial available 850 nm vertical-cavity surface-emitting laser and a bias-T driving circuit. The optical output power of the module varies only by -0.5 dBm +/- 1dB in the required temperature range without active temperature control. In addition we describe a packaging solution for the VCSEL transmitters allowing the operation of the module even in an extreme engine compartment environment, where short term temperature peaks above 125 °C appear.

  14. Elevational Ranges of Birds on a Tropical Montane Gradient Lag behind Warming Temperatures

    PubMed Central

    Forero-Medina, German; Terborgh, John; Socolar, S. Jacob; Pimm, Stuart L.

    2011-01-01

    Background Species may respond to a warming climate by moving to higher latitudes or elevations. Shifts in geographic ranges are common responses in temperate regions. For the tropics, latitudinal temperature gradients are shallow; the only escape for species may be to move to higher elevations. There are few data to suggest that they do. Yet, the greatest loss of species from climate disruption may be for tropical montane species. Methodology/Principal Findings We repeat a historical transect in Peru and find an average upward shift of 49 m for 55 bird species over a 41 year interval. This shift is significantly upward, but also significantly smaller than the 152 m one expects from warming in the region. To estimate the expected shift in elevation we first determined the magnitude of warming in the locality from historical data. Then we used the temperature lapse rate to infer the required shift in altitude to compensate for warming. The range shifts in elevation were similar across different trophic guilds. Conclusions Endothermy may provide birds with some flexibility to temperature changes and allow them to move less than expected. Instead of being directly dependent on temperature, birds may be responding to gradual changes in the nature of the habitat or availability of food resources, and presence of competitors. If so, this has important implications for estimates of mountaintop extinctions from climate change. PMID:22163309

  15. Modelling the effect of temperature on the range expansion of species by reaction-diffusion equations.

    PubMed

    Richter, Otto; Moenickes, Sylvia; Suhling, Frank

    2012-02-01

    The spatial dynamics of range expansion is studied in dependence of temperature. The main elements population dynamics, competition and dispersal are combined in a coherent approach based on a system of coupled partial differential equations of the reaction-diffusion type. The nonlinear reaction terms comprise population dynamic models with temperature dependent reproduction rates subject to an Allee effect and mutual competition. The effect of temperature on travelling wave solutions is investigated for a one dimensional model version. One main result is the importance of the Allee effect for the crossing of regions with unsuitable habitats. The nonlinearities of the interaction terms give rise to a richness of spatio-temporal dynamic patterns. In two dimensions, the resulting non-linear initial boundary value problems are solved over geometries of heterogeneous landscapes. Geo referenced model parameters such as mean temperature and elevation are imported into the finite element tool COMSOL Multiphysics from a geographical information system. The model is applied to the range expansion of species at the scale of middle Europe.

  16. Determining particle size distributions in the inhalable size range for wood dust collected by air samplers.

    PubMed

    Harper, Martin; Muller, Brian S; Bartolucci, Al

    2002-10-01

    In the absence of methods for determining particle size distributions in the inhalable size range with good discrimination, the samples collected by personal air sampling devices can only be characterized by their total mass. This parameter gives no information regarding the size distribution of the aerosol or the size-selection characteristics of different samplers in field use conditions. A method is described where the particles collected by a sampler are removed, suspended, and re-deposited on a mixed cellulose-ester filter, and examined by optical microscopy to determine particle aerodynamic diameters. This method is particularly appropriate to wood dust particles which are generally large and close to rectangular prisms in shape. Over 200 wood dust samples have been collected in three different wood-products industries, using the traditional closed-face polystyrene/acrylonitrile cassette, the Institute of Occupational Medicine inhalable sampler, and the Button sampler developed by the University of Cincinnati. A portion of these samples has been analyzed to determine the limitations of this method. Extensive quality control measures are being developed to improve the robustness of the procedure, and preliminary results suggest the method has an accuracy similar to that required of National Institute for Occupational Safety and Health (NIOSH) methods. The results should provide valuable insights into the collection characteristics of the samplers and the impact of these characteristics on comparison of sampler results to present and potential future limit values. The NIOSH Deep South Education and Research Center has a focus on research into hazards of the forestry and associated wood-products industry, and it is hoped to expand this activity in the future.

  17. Performance and Durability of High Temperature Foil Air Bearing for Oil-Free Turbomachinery

    NASA Technical Reports Server (NTRS)

    DellaCorte, C.; Valco, M. J.; Radil, K. C.; Heshmat, H.

    1999-01-01

    The performance and durability of advanced, high temperature foil air bearings are evaluated under a wide range (10-50 kPa) of loads at temperatures from 25 to 650 C. The bearings are made from uncoated nickel based superalloy foils. The foil surface experiences sliding contact with the shaft during initial start/stop operation. To reduce friction and wear, the solid lubricant coating, PS304, is applied to the shaft by plasma spraying. PS304, is a NiCr based Cr2O3 coating with silver and barium fluoride/calcium fluoride solid lubricant additions. The results show that the bearings provide lives well in excess of 30,000 cycles under all of the conditions tested. Several bearings exhibited lives in excess of 100,000 cycles. Wear is a linear function of the bearing load. The excellent performance measured in this study suggests that these bearings and the PS304 coating are well suited for advanced high temperature, oil-free turbomachinery applications.

  18. Performance and Durability of High Temperature Foil Air Bearings for Oil-Free Turbomachinery

    NASA Technical Reports Server (NTRS)

    DellaCorte, C.; Lukaszewicz, V.; Valco, M. J.; Radil, K. C.; Heshmat, H.

    2000-01-01

    The performance and durability of advanced, high temperature foil air bearings are evaluated under a wide range (10-50 kPa) of loads at temperatures from 25 to 650 C. The bearings are made from uncoated nickel based superalloy foils. The foil surface experiences sliding contact with the shaft during initial start/stop operation. To reduce friction and wear, the solid lubricant coating, PS304, is applied to the shaft by plasma spraying. PS304 is a NiCr based Cr2O3 coating with silver and barium fluoride/calcium fluoride solid lubricant additions. The results show that the bearings provide lives well in excess of 30,000 cycles under all of the conditions tested. Several bearings exhibited lives in excess of 100,000 cycles. Wear is a linear function of the bearing load. The excellent performance measured in this study suggests that these bearings and the PS304 coating are well suited for advanced high temperature, oil-free turbomachinery applications.

  19. Statistical temperature profile retrievals in clear-air using passive 118-GHz O2 observations

    NASA Technical Reports Server (NTRS)

    Gasiewski, A. J.; Johnson, J. T.

    1993-01-01

    The clean-air temperature profile accuracy yielded by a localized linear statistical retrieval operator applied to passive aircraft-based 118-GHz spectra is demonstrated. A comparison of the statistically and physically derived correlation coefficients of antenna temperature and kinetic temperature furnishes a physical justification of the statistical retrieval technique. The atmospheric temperature mean and covariance significantly depend on such geophysical parameters as latitude, longitude, local season, and time, as well as the prevailing meteorological state and orographic effects.

  20. An Air Temperature Cloud Height Precipitation Phase Determination Scheme for Surface Based Modeling

    NASA Astrophysics Data System (ADS)

    Feiccabrino, J. M.

    2015-12-01

    Many hydrological and ecological models use simple surface temperature threshold equations rather than coupling with a complex meteorological model to determine if precipitation is rain or snow. Some comparative studies have found, the most common rain/snow threshold variable, air temperature to have more precipitation phase error than dew-point or wet-bulb temperature, which account for the important secondary role of humidity in the melting and sublimation processes. However, just like surface air temperature, surface humidity is often effected by soil conditions and vegetation and is therefore not always representative of the atmospheric humidity precipitation falls through. A viable alternative to using surface humidity as a proxy for atmospheric moisture would be to adjust the rain snow threshold for changes in cloud height. The height of a cloud base above the ground gives the depth of an unsaturated layer. An unsaturated atmospheric layer should have much different melting and sublimation rates than a saturated cloud layer. Therefore, rain and snow percentages at a given surface air temperature should change with the height of the lowest cloud base. This study uses hourly observations from 12 U.S. manually augmented meteorological stations located in the Great Plains and Midwest upwind or away from major water bodies in relatively flat areas in an attempt to limit geographical influences. The surface air temperature threshold for the ground to 200 feet (under 100m) was 0.0°C, 0.6°C for 300-600 feet (100-200m), 1.1°C for 700-1200 feet (300-400m), 1.7°C for 1300-2000 feet (500-600m), and 2.2°C for 2100-3300 feet (700-1000m). Total precipitation error for these cloud height air temperature thresholds reduced the error from the single air temperature threshold 1.1°C by 15% from 14% to 12% total error between -2.2°C and 3.9°C. These air temperature cloud height thresholds resulted in 1.5% less total error than the dew-point temperature threshold 0.0

  1. Low-temperature ignition delay for hydrogen-air mixtures in light of a reaction mechanism with quantum correction

    NASA Astrophysics Data System (ADS)

    Medvedev, S. P.; Agafonov, G. L.; Khomik, S. V.

    2016-09-01

    A reaction mechanism with quantum correction is used to model low-temperature/high-pressure autoignition of lean hydrogen-air mixtures. This approach provides a good approximation for experimental data on autoignition delay and the low activation energy observed in experiments. Calculated results demonstrate that ignition delay time is inversely proportional to pressure, squared. The proposed scaling reduces spread in experimental data. The application of a quantum correction to hydrogen oxidation provides a basis for developing a general reaction mechanism that can be used to predict the autoignition behavior of hydrogen over an entire temperature/pressure range relevant to rocket engine conditions.

  2. Data Assimilation Experiments Using Quality Controlled AIRS Version 5 Temperature Soundings

    NASA Technical Reports Server (NTRS)

    Susskind, Joel

    2009-01-01

    The AIRS Science Team Version 5 retrieval algorithm has been finalized and is now operational at the Goddard DAAC in the processing (and reprocessing) of all AIRS data. The AIRS Science Team Version 5 retrieval algorithm contains a number of significant improvements over Version 4. Two very significant improvements are described briefly below. 1) The AIRS Science Team Radiative Transfer Algorithm (RTA) has now been upgraded to accurately account for effects of non-local thermodynamic equilibrium on the AIRS observations. This allows for use of AIRS observations in the entire 4.3 micron CO2 absorption band in the retrieval algorithm during both day and night. Following theoretical considerations, tropospheric temperature profile information is obtained almost exclusively from clear column radiances in the 4.3 micron CO2 band in the AIRS Version 5 temperature profile retrieval step. These clear column radiances are a derived product that are indicative of radiances AIRS channels would have seen if the field of view were completely clear. Clear column radiances for all channels are determined using tropospheric sounding 15 micron CO2 observations. This approach allows for the generation of accurate values of clear column radiances and T(p) under most cloud conditions. 2) Another very significant improvement in Version 5 is the ability to generate accurate case-by-case, level-by-level error estimates for the atmospheric temperature profile, as well as for channel-by-channel clear column radiances. These error estimates are used for quality control of the retrieved products. Based on error estimate thresholds, each temperature profiles is assigned a characteristic pressure, pg, down to which the profile is characterized as good for use for data assimilation purposes. We have conducted forecast impact experiments assimilating AIRS quality controlled temperature profiles using the NASA GEOS-5 data assimilation system, consisting of the NCEP GSI analysis coupled with the

  3. Two major volcanic cooling episodes derived from global marine air temperature, AD 1807-1827

    NASA Astrophysics Data System (ADS)

    Chenoweth, Michael

    A new data set of global marine air temperature data for the years 1807-1827 is used to show the impact of volcanic eruptions in ˜ 1809 (unlocated) and 1815 (Tambora, Indonesia). Both eruptions produced cooling exceeding that after Krakatoa, Indonesia (1883) and Pinatubo, Philippines (1991). The ˜1809 eruption is dated to March-June 1808 based on a sudden cooling in Malaysian temperature data and maximum cooling of marine air temperature in 1809. Two large-scale calibrated proxy temperature records, one from tree-ring-density data, the other using multi-proxy sources are compared to the marine air temperature data. Correlation is highest with maximum latewood density data and lowest with the multi-proxy data.

  4. Effects of reproductive status and high ambient temperatures on the body temperature of a free-ranging basoendotherm.

    PubMed

    Levesque, Danielle L; Lobban, Kerileigh D; Lovegrove, Barry G

    2014-12-01

    Tenrecs (Order Afrosoricida) exhibit some of the lowest body temperatures (T b) of any eutherian mammal. They also have a high level of variability in both active and resting T bs and, at least in cool temperatures in captivity, frequently employ both short- and long-term torpor. The use of heterothermy by captive animals is, however, generally reduced during gestation and lactation. We present data long-term T b recordings collected from free-ranging S. setosus over the course of two reproductive seasons. In general, reproductive females had slightly higher (~32 °C) and less variable T b, whereas non-reproductive females and males showed both a higher propensity for torpor as well as lower (~30.5 °C) and more variable rest-phase T bs. Torpor expression defined using traditional means (using a threshold or cut-off T b) was much lower than predicted based on the high degree of heterothermy in captive tenrecs. However, torpor defined in this manner is likely to be underestimated in habitats where ambient temperature is close to T b. Our results caution against inferring metabolic states from T b alone and lend support to the recent call to define torpor in free-ranging animals based on mechanistic and not descriptive variables. In addition, lower variability in T b observed during gestation and lactation confirms that homeothermy is essential for reproduction in this species and probably for basoendothermic mammals in general. The relatively low costs of maintaining homeothermy in a sub-tropical environment might help shed light on how homeothermy could have evolved incrementally from an ancestral heterothermic condition.

  5. Implications of a temperature increase for host plant range: predictions for a butterfly

    PubMed Central

    Audusseau, Hélène; Nylin, Sören; Janz, Niklas

    2013-01-01

    Although changes in phenology and species associations are relatively well-documented responses to global warming, the potential interactions between these phenomena are less well understood. In this study, we investigate the interactions between temperature, phenology (in terms of seasonal timing of larval growth) and host plant use in the polyphagous butterfly Polygonia c-album. We found that the hierarchy of larval performance on three natural host plants was not modified by a temperature increase as such. However, larval performance on each host plant and temperature treatment was affected by rearing season. Even though larvae performed better at the higher temperature regardless of the time of the rearing, relative differences between host plants changed with the season. For larvae reared late in the season, performance was always better on the herbaceous plant than on the woody plants. In this species, it is likely that a prolonged warming will lead to a shift from univoltinism to bivoltinism. The demonstrated interaction between host plant suitability and season means that such a shift is likely to lead to a shift in selective regime, favoring specialization on the herbaceous host. Based on our result, we suggest that host range evolution in response to temperature increase would in this species be highly contingent on whether the population undergoes a predicted shift from one to two generations. We discuss the effect of global warming on species associations and the outcome of asynchrony in rates of phenological change. PMID:24101991

  6. A Study on Flow Behavior of AA5086 Over a Wide Range of Temperatures

    NASA Astrophysics Data System (ADS)

    Asgharzadeh, A.; Jamshidi Aval, H.; Serajzadeh, S.

    2016-03-01

    Flow stress behavior of AA5086 was determined using tensile testing at different temperatures from room temperature to 500 °C and strain rates varying between 0.002 and 1 s-1. The strain rate sensitivity parameter and occurrence of dynamic strain aging were then investigated in which an Arrhenius-type model was employed to study the serrated flow. Additionally, hot deformation behavior at temperatures higher than 320 °C was evaluated utilizing hyperbolic-sine constitutive equation. Finally, a feed forward artificial neural network model with back propagation learning algorithm was proposed to predict flow stress for all deformation conditions. The results demonstrated that the strain rate sensitivity at temperature range of 25-270 °C was negative due to occurrence of dynamic strain aging leading to significant reduction in fracture strain. The serrated yielding activation energy was found to be 46.1 kJ/mol. It indicated that the migration of Mg-atoms could be the main reason for this phenomenon. The hot deformation activation energy of AA5086 was also calculated about 202.3 kJ/mol while the dynamic recovery was the main softening process. Moreover, the ANN model having two hidden layers was shown to be an efficient structure for determining flow stress of the examined alloy for all temperatures and strain rates.

  7. Future Arctic temperature change resulting from a range of aerosol emissions scenarios

    NASA Astrophysics Data System (ADS)

    Wobus, Cameron; Flanner, Mark; Sarofim, Marcus C.; Moura, Maria Cecilia P.; Smith, Steven J.

    2016-06-01

    The Arctic temperature response to emissions of aerosols -- specifically black carbon (BC), organic carbon (OC), and sulfate -- depends on both the sector and the region where these emissions originate. Thus, the net Arctic temperature response to global aerosol emissions reductions will depend strongly on the blend of emissions sources being targeted. We use recently published equilibrium Arctic temperature response factors for BC, OC, and sulfate to estimate the range of present-day and future Arctic temperature changes from seven different aerosol emissions scenarios. Globally, Arctic temperature changes calculated from all of these emissions scenarios indicate that present-day emissions from the domestic and transportation sectors generate the majority of present-day Arctic warming from BC. However, in all of these scenarios, this warming is more than offset by cooling resulting from SO2 emissions from the energy sector. Thus, long-term climate mitigation strategies that are focused on reducing carbon dioxide (CO2) emissions from the energy sector could generate short-term, aerosol-induced Arctic warming. A properly phased approach that targets BC-rich emissions from the transportation sector as well as the domestic sectors in key regions -- while simultaneously working toward longer-term goals of CO2 mitigation -- could potentially avoid some amount of short-term Arctic warming.

  8. FTIR study of carbonate loss from carbonated apatites in the wide temperature range.

    PubMed

    Rau, J V; Cesaro, S Nunziante; Ferro, D; Barinov, S M; Fadeeva, I V

    2004-11-15

    The mineral constituent of bone tissue is a carbonate-substituted apatite (CHA). The thermal stability of the CHA has been revealed to depend on the substitution type and degree, although relatively little is known about this behavior. The aim of this study was to investigate the carbonate loss from synthetic CHAs in equilibrium conditions in a wide temperature range. An approach based on FTIR spectroscopy of condensed gas phase was applied to evaluate the CO and CO2 release with increasing temperature. Four different CHAs were studied, which were prepared by either precipitation from solution or the solid-state interaction. The samples differ from each other by the substitution degree. In one of the samples calcium was partially substituted by magnesium. Decomposition was shown to start at surprisingly low temperature, about 400 degrees C, and the CO content increases monotonously with the increase of temperature. The CO2 content goes through a maximum due to its decomposition into carbon monoxide and oxygen, the temperature of this maximum being strongly dependent on the chemical synthesis route. Therefore, control of the sintering atmosphere with respect to the CO2/CO ratio is needed when preparing the carbonated apatite bioceramics.

  9. Implications of a temperature increase for host plant range: predictions for a butterfly.

    PubMed

    Audusseau, Hélène; Nylin, Sören; Janz, Niklas

    2013-09-01

    Although changes in phenology and species associations are relatively well-documented responses to global warming, the potential interactions between these phenomena are less well understood. In this study, we investigate the interactions between temperature, phenology (in terms of seasonal timing of larval growth) and host plant use in the polyphagous butterfly Polygonia c-album. We found that the hierarchy of larval performance on three natural host plants was not modified by a temperature increase as such. However, larval performance on each host plant and temperature treatment was affected by rearing season. Even though larvae performed better at the higher temperature regardless of the time of the rearing, relative differences between host plants changed with the season. For larvae reared late in the season, performance was always better on the herbaceous plant than on the woody plants. In this species, it is likely that a prolonged warming will lead to a shift from univoltinism to bivoltinism. The demonstrated interaction between host plant suitability and season means that such a shift is likely to lead to a shift in selective regime, favoring specialization on the herbaceous host. Based on our result, we suggest that host range evolution in response to temperature increase would in this species be highly contingent on whether the population undergoes a predicted shift from one to two generations. We discuss the effect of global warming on species associations and the outcome of asynchrony in rates of phenological change.

  10. The long-range transport of Asian air pollution: Its variability and impacts on western North America

    NASA Astrophysics Data System (ADS)

    Reidmiller, David R.

    This dissertation uses measurements from the Mt. Bachelor Observatory (MBO: 43.98° N, 121.69° W; 2.7 km above sea level) in the Cascade Range of central Oregon and elsewhere to investigate the impacts and causes of variability in the Asian long-range transport of air pollution (ALRT) on multiple spatiotemporal scales. Carbon monoxide (CO) observations from MBO, satellite retrievals, a global chemical transport model (CTM) and a backtrajectory index revealed that significant declines (2-21%) in springtime CO at MBO and elsewhere from spring 2005 to spring 2006 were attributable to: (a) strong wildfires in SE Asia during winter 2004 through spring 2005, and (b) the transport pattern in March and April 2006 which limited the inflow of East Asian industrial pollution to the lower free troposphere (FT) over western North America (NA). Ozone (O3) results from 16 CTMs were compared to Clean Air Status and Trends Network (CASTNet) observations in the U.S. for 2001. While the impact of foreign emissions on surface O3 in the U.S. is not negligible (decline of 0.3-0.9 ppbv for a 20% reduction in anthropogenic emissions abroad) - and is of increasing concern given the recent growth in Asian emissions - the effect of NA emissions reductions (decline of 5-6 ppbv for a 20% reduction in anthropogenic O3 precursors) was found to be substantially greater. Chairlift sounding data from MBO revealed that a boundary layer influence at the summit begins ˜10:00 PDT during spring. Using these data, I isolated FT nitrogen oxide (NOX = NO + NO2) observations from 1 autumn and 3 spring campaigns. Significant interannual variability was detected and attributed to changes in FT synoptic conditions. Substantially lower NO X levels were observed during spring 2009 when there were: (1) higher geopotential heights (Z) and warmer temperatures ( T) over the Gulf of Alaska and (2) much weaker winds throughout the North Pacific. A characterization of the top 20 FT NOX events revealed that half (n=10

  11. Comparison of Vertical Soundings and Sidewall Air Temperature Measurements in a Small Alpine Basin

    SciTech Connect

    Whiteman, Charles D.; Eisenbach, Stefan; Pospichal, Bernhard; Steinacker, Reinhold

    2004-11-01

    Tethered balloon soundings from two sites on the floor of a 1-km diameter limestone sinkhole in the Eastern Alps are compared with pseudo-vertical temperature ‘soundings’ from three lines of temperature data loggers on the basin’s northwest, southwest and southeast sidewalls. Under stable nighttime conditions with low background winds, the pseudo-vertical profiles from all three lines were good proxies for free air temperature soundings over the basin center, with a mean nighttime cold temperature bias of about 0.4°C and a standard deviation of 0.4°C. Cold biases were highest in the upper basin where relatively warm air subsides to replace air that spills out of the basin through the lowest altitude saddle. On a windy night, standard deviations increased to 1 - 2°C. After sunrise, the varying exposures of the data loggers to sunlight made the pseudo-vertical profiles less useful as proxies for free air soundings. The good correspondence between sidewall and free air temperatures during high static stability conditions suggests that sidewall soundings will prove useful in monitoring temperatures and vertical temperature gradients in the sinkhole. The sidewall soundings can produce more frequent profiles at less cost than tethersondes or rawinsondes, and provide valuable advantages for some types of meteorological analyses.

  12. TSDC study of XLPE recrystallization effects in the melting range of temperatures

    NASA Astrophysics Data System (ADS)

    Diego, J. A.; Belana, J.; Òrrit, J.; Sellarès, J.; Mudarra, M.; Cañadas, J. C.

    2006-05-01

    The electrical properties of crosslinked polyethylene (XLPE), employed in mid-voltage cable insulation are studied using thermally stimulated depolarization currents (TSDC), differential scanning calorimetry (DSC) and x-ray diffraction. A complex heteropolar peak appears by TSDC between 50 and 110 °C, with a maximum at 105 °C. These measurements reveal that there is an optimal polarization temperature (Tpo) around 90 °C. For this polarization temperature, the measured discharge peak area is maximum. Although the presence of a Tpo is common in the study of relaxations by TSDC, in this case one would expect a monotonic decrease in the TSDC response with increasing polarization temperatures due to the decrease in the total crystalline fraction. In this paper, TSDC curves obtained under several conditions are interpreted in terms of recrystallization processes in XLPE during the polarization stage, if the sample is polarized in the melting temperature range. In this case, the recrystallization of a fraction of the material molten at this temperature promotes the formation of more stable and defect-free crystals. The presence of recrystallization processes is detected by DSC and confirmed by x-ray diffractometry. TSDC measurements have been performed with samples polarized at several temperatures (Tp) cooling from the melt or heating from room temperature. Also, TSDC results are obtained with previous annealing or with several cooling rates. These results allow us to infer that crystalline material grown from recrystallization processes that take place in the polarization stage attains a particularly stable polarization. Possible microscopical causes of this effect are discussed.

  13. Air temperature distribution over a debris covered glacier in the Nepalese Himalayas

    NASA Astrophysics Data System (ADS)

    Pellicciotti, Francesca; Petersen, Lene; Wicki, Simon; Carenzo, Marco; Immerzeel, Walter

    2013-04-01

    Air temperature is a key control in the exchange of energy fluxes at the glacier-atmosphere interface and also the main input variable in many of the melt models (both energy balance or temperature-index type of models) currently used to predict glacier melt across a variety of scales. The commonly used approach to derive distributed temperature inputs is extrapolation from point measurements, often located outside the glacier surface, with a lapse rate that is assumed to be constant in time and uniform in space. Previous work for debris free glaciers has shown that lapse rates depend on several factors such as katabatic wind, humidity and the presence of clouds and that they vary in space and time. A dominant control however seems to be the presence of katabatic wind. For debris covered glaciers, the driving forces of air temperature are likely to be different but little is known because of the scarcity of field observations. Few preliminary studies have suggested that there is a strong coupling between surface and 2 m air temperature, while strong katabatic wind does not develop on debris covered tongues. In this study, we examine the variability in air temperature and lapse rates, as well as its atmospheric controls under different meteorological settings for the debris covered Lirung Glacier in the Nepalese Himalayas. We use a recently collected data set of air and surface temperature at a network of locations on the glacier tongue during the pre-monsoon season and the entire monsoon season of 2012. Additionally an AWS was installed on the glacier allowing the collection of meteorological observations. We investigate differences in air temperature during different climatic conditions (monsoon vs. dry period, upvalley vs. downvalley wind, cloudy vs. clear-sky, etc.). We identify the main controls on temperature and discuss how appropriate the application of a temperature lapse rate is over a debris covered glacier by investigating the correlation between

  14. Application of high temperature air heaters to advanced power generation cycles

    SciTech Connect

    Thompson, T R; Boss, W H; Chapman, J N

    1992-03-01

    Recent developments in ceramic composite materials open up the possibility of recuperative air heaters heating air to temperatures well above the feasible with metal tubes. A high temperature air heater (HTAH) has long been recognized as a requirement for the most efficient MHD plants in order to reach high combustor flame temperatures. The application of gas turbines in coal-fired plants of all types has been impeded because of the problems in cleaning exhaust gas sufficiently to avoid damage to the turbine. With a possibility of a HTAH, such plants may become feasible on the basis of air turbine cycles, in which air is compressed and heated in the HTAH before being applied to turbine. The heat exchanger eliminates the need for the hot gas cleanup system. The performance improvement potential of advanced cycles with HTAH application including the air turbine cycle in several variations such as the DOE program on ``Coal-Fired Air Furnace Combined Cycle...,`` variations originated by the authors, and the MHD combined cycle are presented. The status of development of ceramic air heater technology is included.

  15. Size effect on high temperature variable range hopping in Al+ implanted 4H-SiC

    NASA Astrophysics Data System (ADS)

    Parisini, Antonella; Parisini, Andrea; Nipoti, Roberta

    2017-01-01

    The hole transport properties of heavily doped 4H-SiC (Al) layers with Al implanted concentrations of 3  ×  1020 and 5  ×  1020 cm-3 and annealed in the temperature range 1950-2100 °C, have been analyzed to determine the main transport mechanisms. This study shows that the temperature dependence of the resistivity (conductivity) may be accounted for by a variable range hopping (VRH) transport into an impurity band. Depending on the concentration of the implanted impurities and the post-implantation annealing treatment, this VRH mechanism persists over different temperature ranges that may extend up to room temperature. In this framework, two different transport regimes are identified, having the characteristic of an isotropic 3D VRH and an anisotropic nearly 2D VRH. The latter conduction mechanism appears to take place in a rather thick layer (about 400 nm) that is too large to induce a confinement effect of the carrier hops. The possibility that an anisotropic transport may be induced by a structural modification of the implanted layer because of a high density of basal plane stacking faults (SF) in the implanted layers is considered. The interpretation of the conduction in the heaviest doped samples in terms of nearly 2D VRH is supported by the results of the transmission electron microscopy (TEM) investigation on one of the 5  ×  1020 cm-3 Al implanted samples of this study. In this context, the average separation between basal plane SFs, measured along the c-axis, which is orthogonal to the carrier transport during electrical characterization, appears to be in keeping with the estimated value of the optimal hopping length of the VRH theory. Conversely, no SFs are detected by TEM in a sample with an Al concentration of 1  ×  1019 cm-3 where a 3D nearest neighbor hopping (NNH) transport is observed.

  16. Evaluation of simulated climatological diurnal temperature range in CMIP5 models from the perspective of planetary boundary layer turbulent mixing

    NASA Astrophysics Data System (ADS)

    Wei, Nan; Zhou, Liming; Dai, Yongjiu

    2016-08-01

    This study examines the effects of modeled planetary boundary layer (PBL) mixing on the simulated temperature diurnal cycle climatology over land in 20 CMIP5 models with AMIP simulations. When compared with observations, the magnitude of diurnal temperature range (DTR) is systematically underestimated over almost all land areas due to a widespread warm bias of daily minimum temperature (Tmin) and mostly a cold bias of daily maximum temperature (Tmax). Analyses of the CMIP5 multi-model ensemble means suggest that the biases of the simulated PBL mixing could very likely contribute to the temperature biases. For the regions with the cold bias in Tmax, the daytime PBL mixing is generally underestimated. The consequent more dry air entrainment from the free atmosphere could help maintain the surface humidity gradient, and thus produce more surface evaporation and potentially lower the Tmax. The opposite situation holds true for the regions with the warm bias of Tmax. This mechanism could be particularly applicable to the regions with moderate and wet climate conditions where surface evaporation depends more on the surface humidity gradient, but less on the available soil moisture. For the widespread warm bias of Tmin, the widely-recognized overestimated PBL mixing at nighttime should play a dominant role by transferring more heat from the atmosphere to the near-surface to warm the Tmin. Further analyses using the high resolution CFMIP2 output also support the CMIP5 results about the connections of the biases between the simulated turbulent mixing and the temperature diurnal cycle. The large inter-model variations of the simulated temperature diurnal cycle primarily appear over the arid and semi-arid regions and boreal arctic regions where the model differences in the PBL turbulence mixing could make equally significant contributions to the inter-model variations of DTR, Tmax and Tmin compared to the model differences in surface radiative processes. These results

  17. Thermal Coupling between Air and Ground Temperatures in the CMIP5 Historical and Future Simulations

    NASA Astrophysics Data System (ADS)

    García-García, Almudena; José Cuesta-Valero, Francisco; Beltrami, Hugo; Smerdon, Jason

    2016-04-01

    The decadal-scale thermal coupling between air and ground temperatures across North America is examined for 32 General Circulation Models (GCMs) from the fifth phase of the Coupled Model Intercomparison Project (CMIP5). For each simulation, we evaluate the relationship between air and ground temperatures. Our results show that the transport of energy across the air-ground interface differs from observations, and among GCMs depending on each model's land-surface component. While the decadal variability among GCMs can be explained by the physics and parameterizations of each land-surface model, the spatial variability of the air-ground coupling for the historical and future simulations is associated with model treatment of the soil thermal properties as well as with processes associated with snow and vegetation cover within GCMs. The difference between air and ground temperatures at high latitudes within the majority of the CMIP5 models is related to the insulating effect of snow cover. On the other hand, the difference between air and ground temperatures at low latitudes within some of the CMIP5 models is inversely proportional to the leaf area index, due to changes in latent and sensible heat fluxes. The large variability among GCMs and the marked dependency of the results on the choice of the land-surface model illustrates the need for improving the simulation of air-ground coupling in land-surface models towards a robust simulation of near-surface processes, such as permafrost and soil carbon stability within GCMs.

  18. Characteristics of Gaseous Diffusion Flames with High Temperature Combustion Air in Microgravity

    NASA Technical Reports Server (NTRS)

    Ghaderi, M.; Gupta, A. K.

    2003-01-01

    The characteristics of gaseous diffusion flames have been obtained using high temperature combustion air under microgravity conditions. The time resolved flame images under free fall microgravity conditions were obtained from the video images obtained. The tests results reported here were conducted using propane as the fuel and about 1000 C combustion air. The burner included a 0.686 mm diameter central fuel jet injected into the surrounding high temperature combustion air. The fuel jet exit Reynolds number was 63. Several measurements were taken at different air preheats and fuel jet exit Reynolds number. The resulting hybrid color flame was found to be blue at the base of the flame followed by a yellow color flame. The length and width of flame during the entire free fall conditions has been examined. Also the relative flame length and width for blue and yellow portion of the flame has been examined under microgravity conditions. The results show that the flame length decreases and width increases with high air preheats in microgravity condition. In microgravity conditions the flame length is larger with normal temperature combustion air than high temperature air.

  19. Influence of intake air temperature on internal combustion engine operation

    NASA Astrophysics Data System (ADS)

    Birtok-Băneasă, C.; Raţiu, S.; Hepuţ, T.

    2017-01-01

    This paper presents three methods for reduce thermal losses in the intake system with improvement of airflow and thermal protection. In the experiment are involved two patented devices conceived by the author and one PhD theme device: 1- Dynamic device for air transfer, 2-Integrated thermal deflector, and, 3-Advanced thermal protection. The tests were carried on different vehicle running in real traffic and in the Internal Combustion Engines Laboratory, within the specialization “Road vehicle” belonging to the Faculty of Engineering Hunedoara, component of Politehnica University of Timişoara. The results have been processed and compared whit the ones obtained without these devices.

  20. Improved Determination of Surface and Atmospheric Temperatures Using Only Shortwave AIRS Channels: The AIRS Version 6 Retrieval Algorithm

    NASA Technical Reports Server (NTRS)

    Susskind, Joel; Blaisdell, John; Iredell, Lena

    2010-01-01

    AIRS was launched on EOS Aqua on May 4, 2002 together with ASMU-A and HSB to form a next generation polar orbiting infrared and microwave atmosphere sounding system (Pagano et al 2003). The theoretical approach used to analyze AIRS/AMSU/HSB data in the presence of clouds in the AIRS Science Team Version 3 at-launch algorithm, and that used in the Version 4 post-launch algorithm, have been published previously. Significant theoretical and practical improvements have been made in the analysis of AIRS/AMSU data since the Version 4 algorithm. Most of these have already been incorporated in the AIRS Science Team Version 5 algorithm (Susskind et al 2010), now being used operationally at the Goddard DISC. The AIRS Version 5 retrieval algorithm contains three significant improvements over Version 4. Improved physics in Version 5 allowed for use of AIRS clear column radiances (R(sub i)) in the entire 4.3 micron CO2 absorption band in the retrieval of temperature profiles T(p) during both day and night. Tropospheric sounding 15 micron CO2 observations were used primarily in the generation of clear column radiances (R(sub i)) for all channels. This new approach allowed for the generation of accurate Quality Controlled values of R(sub i) and T(p) under more stressing cloud conditions. Secondly, Version 5 contained a new methodology to provide accurate case-by-case error estimates for retrieved geophysical parameters and for channel-by-channel clear column radiances. Thresholds of these error estimates are used in a new approach for Quality Control. Finally, Version 5 contained for the first time an approach to provide AIRS soundings in partially cloudy conditions that does not require use of any microwave data. This new AIRS Only sounding methodology was developed as a backup to AIRS Version 5 should the AMSU-A instrument fail. Susskind et al 2010 shows that Version 5 AIRS Only sounding are only slightly degraded from the AIRS/AMSU soundings, even at large fractional cloud