Science.gov

Sample records for measures mitigating heat

  1. Heat Island Mitigation Measures in Response to Climate Change Impacts

    NASA Technical Reports Server (NTRS)

    Quattrochi, Dale a.; Estes, Maurice, Jr.; Crosson, William; Al-Hamdan, Mohammad

    2010-01-01

    This slide presentation examines the effect of cities, the accompanying heat island effect, and other impacts that urbanization has had on the environment. Various satellite views of several urban areas are shown.

  2. Secondary effects of urban heat island mitigation measures on air quality

    NASA Astrophysics Data System (ADS)

    Fallmann, Joachim; Forkel, Renate; Emeis, Stefan

    2016-01-01

    This study presents numerical simulations analysing the effect of urban heat island (UHI) mitigation measures on the chemical composition of the urban atmosphere. The mesoscale chemical transport model WRF-Chem is used to investigate the impact of urban greening and highly reflective surfaces on the concentrations of primary (CO, NO) as well as secondary pollutants (O3) inside the urban canopy. In order to account for the sub-grid scale heterogeneity of urban areas, a multi-layer urban canopy model is coupled to WRF-Chem. Using this canopy model at its full extend requires the introduction of several urban land use classes in WRF-Chem. The urban area of Stuttgart serves as a test bed for the modelling of a case scenario of the 2003 European Heat Wave. The selected mitigation measures are able to reduce the urban temperature by about 1 K and the mean ozone concentration by 5-8%. Model results however document also negative secondary effects on urban air quality, which are closely related to a decrease of vertical mixing in the urban boundary layer. An increase of primary pollutants NO and CO by 5-25% can be observed. In addition, highly reflective surfaces can increase peak ozone concentration by up to 12% due to a high intensity of reflected shortwave radiation accelerating photochemical reactions.

  3. Composition and sources of PM2.5 around the heating periods of 2013 and 2014 in Beijing: Implications for efficient mitigation measures

    NASA Astrophysics Data System (ADS)

    Yang, Hainan; Chen, Jing; Wen, Jiaojiao; Tian, Hezhong; Liu, Xingang

    2016-01-01

    The diurnal variations of the water soluble organic and inorganic components as well as six selected metals in PM2.5 around the heating periods of 2013 and 2014 in Beijing were analyzed in this study to investigate the contributions of secondary aerosols and primary pollutants to PM2.5 and the effects of domestic heating and mitigation measures. The before-heating sampling period in 2014 (from Nov. 1st to Nov. 15th) was characterized with reinforced short-term mitigation measures for the 2014 Asia-Pacific Economic Cooperation (APEC) meeting. As a result, the average mass concentrations of PM2.5 and most of the measured species except for Cu, Al, and Ca2+ were greatly reduced during the APEC meeting period. The domestic heating activity alone resulted in a 17.7% increase of PM2.5 in 2013, exerting lesser effects on the increase of PM2.5 than before. Water soluble organic carbon was the most abundant water soluble species in PM2.5, followed by NO3-, SO42-, and NH4+ . According to the PMF model calculation, secondary aerosols, coal combustion, biomass/waste burning, traffic related pollution, long-range transport, and fugitive soil and sand dust were identified as the main sources of PM2.5 in Beijing, among which secondary formation of aerosols was the dominant source of PM2.5 during the non-APEC period while biomass/waste burning dominated during the APEC period. As a timely feedback on the effects of the mitigation measures adopted by the government, the results of this study provide knowledge necessary for a sustainable urban management.

  4. Pre-heating mitigates composite degradation

    PubMed Central

    da SILVA, Jessika Calixto; Rogério Vieira, REGES; REGE, Inara Carneiro Costa; CRUZ, Carlos Alberto dos Santos; VAZ, Luís Geraldo; ESTRELA, Carlos; de CASTRO, Fabrício Luscino Alves

    2015-01-01

    ABSTRACT Dental composites cured at high temperatures show improved properties and higher degrees of conversion; however, there is no information available about the effect of pre-heating on material degradation. Objectives This study evaluated the effect of pre-heating on the degradation of composites, based on the analysis of radiopacity and silver penetration using scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS). Material and Methods Thirty specimens were fabricated using a metallic matrix (2x8 mm) and the composites Durafill VS (Heraeus Kulzer), Z-250 (3M/ESPE), and Z-350 (3M/ESPE), cured at 25°C (no pre-heating) or 60°C (pre-heating). Specimens were stored sequentially in the following solutions: 1) water for 7 days (60°C), plus 0.1 N sodium hydroxide (NaOH) for 14 days (60°C); 2) 50% silver nitrate (AgNO3) for 10 days (60°C). Specimens were radiographed at baseline and after each storage time, and the images were evaluated in gray scale. After the storage protocol, samples were analyzed using SEM/EDS to check the depth of silver penetration. Radiopacity and silver penetration data were analyzed using ANOVA and Tukey’s tests (α=5%). Results Radiopacity levels were as follows: Durafill VSZ-350>Z-250 (p<0.05). After storage in water/NaOH, pre-heated specimens presented higher radiopacity values than non-pre-heated specimens (p<0.05). There was a lower penetration of silver in pre-heated specimens (p<0.05). Conclusions Pre-heating at 60°C mitigated the degradation of composites based on analysis of radiopacity and silver penetration depth. PMID:26814459

  5. Pre-heating mitigates composite degradation.

    PubMed

    Silva, Jessika Calixto da; Rogério Vieira, Reges; Rege, Inara Carneiro Costa; Cruz, Carlos Alberto dos Santos; Vaz, Luís Geraldo; Estrela, Carlos; Castro, Fabrício Luscino Alves de

    2015-01-01

    Dental composites cured at high temperatures show improved properties and higher degrees of conversion; however, there is no information available about the effect of pre-heating on material degradation. Objectives This study evaluated the effect of pre-heating on the degradation of composites, based on the analysis of radiopacity and silver penetration using scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS). Material and Methods Thirty specimens were fabricated using a metallic matrix (2x8 mm) and the composites Durafill VS (Heraeus Kulzer), Z-250 (3M/ESPE), and Z-350 (3M/ESPE), cured at 25°C (no pre-heating) or 60°C (pre-heating). Specimens were stored sequentially in the following solutions: 1) water for 7 days (60°C), plus 0.1 N sodium hydroxide (NaOH) for 14 days (60°C); 2) 50% silver nitrate (AgNO3) for 10 days (60°C). Specimens were radiographed at baseline and after each storage time, and the images were evaluated in gray scale. After the storage protocol, samples were analyzed using SEM/EDS to check the depth of silver penetration. Radiopacity and silver penetration data were analyzed using ANOVA and Tukey's tests (α=5%). Results Radiopacity levels were as follows: Durafill VSZ-350>Z-250 (p<0.05). After storage in water/NaOH, pre-heated specimens presented higher radiopacity values than non-pre-heated specimens (p<0.05). There was a lower penetration of silver in pre-heated specimens (p<0.05). Conclusions Pre-heating at 60°C mitigated the degradation of composites based on analysis of radiopacity and silver penetration depth.

  6. Heat waves in urban heat islands: interactions, impacts, and mitigation

    NASA Astrophysics Data System (ADS)

    Bou-Zeid, E.; Li, D.

    2013-12-01

    Urbanization rates and the intensity of anthropogenic global warming are both on the rise. By the middle of this century, climate change impacts on humans will be largely manifested in urban regions and will result from a combination of global to regional impacts related to greenhouse gas emissions, as well as regional to local impacts related to land-cover changes associated with urbanization. Alarmingly, our understanding of how these two distinct impacts will interact remains very poor. One example, which is the focus of this study, is the interaction of urban heat islands and heat waves. Urban heat islands (UHIs) are spatial anomalies consisting of higher temperatures over built terrain; while their intensity varies with many factors, it consistently increases with city size. UHIs will hence intensify in the future as cities expand. Heat waves are temporal anomalies in the regional temperatures that affect both urban and rural areas; there is high certainty that the frequency and intensity of such waves will increase as a result global warming. However, whether urban and rural temperatures respond in the same way to heat waves remains a critical unanswered question. In this study, a combination of observational and modeling analyses of a heat wave event over the Baltimore-Washington urban corridor reveals synergistic interactions between urban heat islands and heat waves. Not only do heat waves increase the regional temperatures, but they also intensify the difference between urban and rural temperatures. That is, their impact is stronger in cities and the urban heat stress during such waves is larger than the sum of the background urban heat island effect and the heat wave effect. We also develop a simple analytical model of this interaction that suggests that this exacerbated impact in urban areas is primarily to the lack of surface moisture, with low wind speeds also playing a smaller role. Finally, the effectiveness of cool and green roofs as UHI mitigation

  7. The Urban Heat Island Phenomenon and Potential Mitigation Strategies

    NASA Technical Reports Server (NTRS)

    Estes, Maurice G., Jr.; Gorsevski, Virginia; Russell, Camille; Quattrochi, Dale; Luvall, Jeffrey

    1999-01-01

    A survey of urban heat island research is provided to describe how heat islands develop, urban landscape and meteorological characteristics that facilitate development, use of aircraft remote sensing data, and why heat islands are of interest to planners, elected officials, and the public. The roles of the National Aeronautics and Space Administration (NASA), the Environmental Protection Agency (EPA), other federal agencies, national laboratories and universities, state and local governments, and non-governmental organizations (NGOS) in studying the urban heat island effect and developing mitigation strategies are explored. Barriers that hamper mitigation efforts and case studies in Atlanta and Salt Lake City are discussed.

  8. Debris mitigation measures of Russian launchers

    NASA Astrophysics Data System (ADS)

    Utkin, V. F.; Chekalin, S. V.; Lukiyashchenko, V. I.

    1995-08-01

    The paper contains the statistics of SLV launches by the former USSR briefly characterising them as space pollution sources. The major principles of forming the Russian launch capability system and measures undertaken to improve SLV ecological indices, in particular, the measures to mitigate near-earth space pollution with separated elements and to prevent in-orbit used rocket stage explosions are spoken about. In conclusion, recommendations as regards novel developments and concrete proposals to arrange international cooperation in this area are given.

  9. Paving materials for heat island mitigation

    SciTech Connect

    Pomerantz, M.; Akbari, H.; Chen, A.; Taha, H.; Rosenfeld, A.H.

    1997-11-01

    This report summarizes paving materials suitable for urban streets, driveways, parking lots and walkways. The authors evaluate materials for their abilities to reflect sunlight, which will reduce their temperatures. This in turn reduces the excess air temperature of cities (the heat island effect). The report presents the compositions of the materials, their suitability for particular applications, and their approximate costs (in 1996). Both new and resurfacing are described. They conclude that, although light-colored materials may be more expensive than conventional black materials, a thin layer of light-colored pavement may produce energy savings and smog reductions whose long-term worth is greater than the extra cost.

  10. Space debris mitigation measures in India

    NASA Astrophysics Data System (ADS)

    Adimurthy, V.; Ganeshan, A. S.

    2006-02-01

    The Indian Space Research Organization (ISRO) recognizes the importance of the current space debris scenario, and the impact it has on the effective utilization of space technology for the improvement in the quality of life on the Earth. ISRO is committed to effective management of the threats due to space debris. Towards this commitment ISRO works on different aspects of space debris, including the debris mitigation measures. This paper highlights the activities and achievements in the implementation of the mitigation measures. ISRO successfully designed and developed a propellant venting system for implementation in the existing upper stage of India's Polar Satellite Launch Vehicle (PSLV), which uses Earth-storable liquid propellants. GSLV also employs passivation of the Cryogenic Upper Stage at the end of its useful mission. ISRO's communication satellites in GSO are designed with adequate propellant margins for re-orbiting at the end of their useful life to a higher graveyard orbit. A typical successful operation in connection with INSAT-2C is described. ISRO developed its debris environmental models and software to predict the close approach of any of the debris to the functional satellites. The software are regularly used for the debris risk management of the orbiting spacecraft and launch vehicles. ISRO recognizes the role of international cooperation in the debris mitigation measures and actively contributes to the efforts of the Inter-Agency Space Debris Coordination Committee (IADC) and United Nations Committee on the Peaceful Uses of Outer Space (UNCOPUOS).

  11. Mitigation measures and programs in Hungary

    SciTech Connect

    Molnar, S.

    1996-12-31

    In Hungary there are four main governmental programs, which may result in a decrease of emissions of anthropogenic greenhouse gases (GHGs): (1) National program of energy efficiency improvement and energy conservation, (2) Afforestation program, (3) Volatile organic compounds (VOC) emission reduction program, and (4) Program to reduce the use of ozone depleting substances. These ambitious programs were launched in the beginning of the 90`s, but they have been slowed down because of budgetary problems. The comprehensive action plan for mitigation of GHG emissions should be based on these ongoing programs. These programs should be expanded by further measures and programs in order to fulfill the requirements of the FCCC. In the next sections the results and prospects of the above mentioned programs will be summarized. Also the results of the mitigation study supported by the U.S. Country Studies Program are included.

  12. Radon measurement and mitigation activity in Finland.

    PubMed

    Valmari, T; Arvela, H; Reisbacka, H; Holmgren, O

    2014-07-01

    Radon prevention, measurement and mitigation activities have been increasing in Finland during the 2000s. Nowadays, many municipal authorities, especially those located in high-radon areas, require radon prevention measures. This has activated radon measurements. Owners of new houses having radon piping installed under the floor slab are the most active group to measure and reduce the found high-radon values. Their radon awareness is apparently better than on the average, and the existing piping makes it easier and cheaper to reduce the radon levels. Local campaigns involving invitation flyers mailed to the residents have been a cost-effective means to activate measurements of older houses. So far 116,611 dwellings in low-rise residential buildings have been measured. At least 15% of the 16,860 dwellings found to exceed the reference level of 400 Bq m(-3) had their indoor radon level reduced below that.

  13. Heat Flow Measurement

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Heat gauges are used to measure heat flow in industrial activities. They must periodically be certified by instruments designed to provide a heat flux measurement standard. CSTAR, a NASA CCDS, and REMTECH have developed a portable heat flux checker/calibrator. The Q-CHEC can be carried to the heat gauge for certification, reducing out of service time for the gauge and eliminating the need for a replacement gauge during certification. It can provide an "end-to-end" check of the instrumentation measurement system or be used as a standalone calibrator. Because Q-CHEC offers on-site capability to detect and eliminate measurement errors, measurements do not have to be repeated, and money is saved.

  14. Heat flux measurements

    NASA Technical Reports Server (NTRS)

    Liebert, Curt H.; Weikle, Donald H.

    1989-01-01

    A new automated, computer controlled heat flux measurement facility is described. Continuous transient and steady-state surface heat flux values varying from about 0.3 to 6 MW/sq m over a temperature range of 100 to 1200 K can be obtained in the facility. An application of this facility is the development of heat flux gauges for continuous fast transient surface heat flux measurement on turbine blades operating in space shuttle main engine turbopumps. The facility is useful for durability testing at fast temperature transients.

  15. 13 CFR 123.21 - What is a mitigation measure?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false What is a mitigation measure? 123.21 Section 123.21 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Overview § 123.21 What is a mitigation measure? A mitigation measure is something done for the purpose...

  16. 13 CFR 123.21 - What is a mitigation measure?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false What is a mitigation measure? 123.21 Section 123.21 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Overview § 123.21 What is a mitigation measure? A mitigation measure is something done for the purpose...

  17. 13 CFR 123.21 - What is a mitigation measure?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false What is a mitigation measure? 123.21 Section 123.21 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Overview § 123.21 What is a mitigation measure? A mitigation measure is something done for the purpose...

  18. 13 CFR 123.21 - What is a mitigation measure?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false What is a mitigation measure? 123.21 Section 123.21 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Overview § 123.21 What is a mitigation measure? A mitigation measure is something done for the purpose...

  19. 13 CFR 123.21 - What is a mitigation measure?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false What is a mitigation measure? 123.21 Section 123.21 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Overview § 123.21 What is a mitigation measure? A mitigation measure is something done for the purpose...

  20. Numerical simulations of urban heat island mitigation strategies in Vienna

    NASA Astrophysics Data System (ADS)

    Koch, Roland; Zuvela-Aloise, Maja

    2013-04-01

    Effects of change in land use on daytime urban heat island (UHI) of Vienna is investigated using the local-scale atmospheric model MUKLIMO3 developed at the German Weather Service (DWD). Assuming that the observed trend towards urbanization negatively impacts the heat stress of urban areas, it becomes increasingly important to develop UHI mitigation strategies that aims to reduce the urban heat stress. The purpose of this study is to gain a further understanding of the structure of the daytime UHI in Vienna and to investigate the question to what degree changes in the urban land use affect the near-surface climate and heat stress in the city. The qualitative and quantitative characterization of the UHI is obtained by the computation of the mean annual number of summer days (Tmax × 25° C) of the 1981-2010 period using the so-called cuboid method (DWD). A set of mitigation strategies is developed and applied to MUKLIMO3 simulation experiments. The strategies take into account the change in urban land use as well as the modification of land use features. Results confirm the importance of green areas, water ways and pervious surfaces in the city. In addition, the size, location and distribution of new vegetated areas, i.e. parks, can crucially alter the urban heat stress. In view of the unique character of the city, the realization of adequate mitigation strategies is mainly limited to the existing urban land use. The obtained model results are intended to provide additional information for the city planners.

  1. Planetary heat flow measurements.

    PubMed

    Hagermann, Axel

    2005-12-15

    The year 2005 marks the 35th anniversary of the Apollo 13 mission, probably the most successful failure in the history of manned spaceflight. Naturally, Apollo 13's scientific payload is far less known than the spectacular accident and subsequent rescue of its crew. Among other instruments, it carried the first instrument designed to measure the flux of heat on a planetary body other than Earth. The year 2005 also should have marked the launch of the Japanese LUNAR-A mission, and ESA's Rosetta mission is slowly approaching comet Churyumov-Gerasimenko. Both missions carry penetrators to study the heat flow from their target bodies. What is so interesting about planetary heat flow? What can we learn from it and how do we measure it?Not only the Sun, but all planets in the Solar System are essentially heat engines. Various heat sources or heat reservoirs drive intrinsic and surface processes, causing 'dead balls of rock, ice or gas' to evolve dynamically over time, driving convection that powers tectonic processes and spawns magnetic fields. The heat flow constrains models of the thermal evolution of a planet and also its composition because it provides an upper limit for the bulk abundance of radioactive elements. On Earth, the global variation of heat flow also reflects the tectonic activity: heat flow increases towards the young ocean ridges, whereas it is rather low on the old continental shields. It is not surprising that surface heat flow measurements, or even estimates, where performed, contributed greatly to our understanding of what happens inside the planets. In this article, I will review the results and the methods used in past heat flow measurements and speculate on the targets and design of future experiments.

  2. Characterization of heat loads from mitigated and unmitigated vertical displacement events in DIII-D

    SciTech Connect

    Hollmann, E. M.; Moyer, R. A.; Commaux, N.; Jernigan, T. J.; Eidietis, N. W.; Humphreys, D. A.; Strait, E. J.; Wesley, J. C.; Lasnier, C. J.; Pitts, R. A.; Sugihara, M.; Watkins, J.

    2013-06-15

    Experiments have been conducted on the DIII-D tokamak to study the distribution and repeatability of heat loads and vessel currents resulting from vertical displacement events (VDEs). For unmitigated VDEs, the radiated power fraction appears to be of order 50%, with the remaining power dominantly conducted to the vessel walls. Shot-to-shot scatter in heat loads measured at one toroidal location is not large (<±50%), suggesting that toroidal asymmetries in conducted heat loads are not large. Conducted heat loads are clearly observed during the current quench (CQ) of both mitigated and unmitigated disruptions. Significant poloidal asymmetries in heat loads and radiated power are often observed in the experiments but are not yet understood. Energy dissipated resistively in the conducting walls during the CQ appears to be small (<5%). The mitigating effect of neon massive gas injection (MGI) as a function of MGI trigger delay has also been studied. Improved mitigation is observed as the MGI trigger delay is decreased. For sufficiently early MGI mitigation, close to 100% radiated energy and a reduction of roughly a factor 2 in vessel forces is achieved.

  3. Latent Heat in Soil Heat Flux Measurements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The surface energy balance includes a term for soil heat flux. Soil heat flux is difficult to measure because it includes conduction and convection heat transfer processes. Accurate representation of soil heat flux is an important consideration in many modeling and measurement applications. Yet, the...

  4. Heat island mitigation using water retentive pavement sprinkled with reclaimed wastewater.

    PubMed

    Yamagata, H; Nasu, M; Yoshizawa, M; Miyamoto, A; Minamiyama, M

    2008-01-01

    In Japan, reclaimed wastewater has been recycled widely for non-potable urban applications and it is to be used for sprinkling roads to mitigate heat island in urban areas. To assess the heat island mitigation effects of the sprinkling reclaimed wastewater on water retentive pavement, we carried out a survey at Shiodome-District, Tokyo. The temperatures of air and roads, humidity, and WBGT (Wet-bulb globe temperature) were measured and heat flux was estimated to compare the condition of the areas with/without sprinkling. The following results were obtained. 1) Sprinkling reclaimed wastewater decreased the road surface temperature by 8 degrees during the daytime and by 3 degrees at night: temperatures equal to those on planting zones. Nevertheless sprinkling was done only in the daytime, the temperature decrease effect was not only obtained during the daytime: it continued through the night, due to the water retentive pavement. 2) Sprinkling reclaimed wastewater reduced the amount of sensible heat flux and increased that of latent heat flux. These results suggest that sprinkling reclaimed wastewater on water retentive pavement can effectively mitigate the heat island phenomenon.

  5. Structural master plan of flood mitigation measures

    NASA Astrophysics Data System (ADS)

    Heidari, A.

    2009-01-01

    Flood protection is one of the practical methods in damage reduction. Although it not possible to be completely protected from flood disaster but major part of damages can be reduced by mitigation plans. In this paper, the optimum flood mitigation master plan is determined by economic evaluation in trading off between the construction costs and expected value of damage reduction as the benefits. Size of the certain mitigation alternative is also be obtained by risk analysis by accepting possibility of flood overtopping. Different flood mitigation alternatives are investigated from various aspects in the Dez and Karun river floodplain areas as a case study in south west of IRAN. The results show that detention dam and flood diversion are the best alternatives of flood mitigation methods as well as enforcing the flood control purpose of upstream multipurpose reservoirs. Dyke and levees are not mostly justifiable because of negative impact on down stream by enhancing routed flood peak discharge magnitude and flood damages as well.

  6. 50 CFR 665.812 - Sea turtle take mitigation measures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Sea turtle take mitigation measures. 665... Pacific Pelagic Fisheries § 665.812 Sea turtle take mitigation measures. (a) Possession and use of... sea turtle handling requirements set forth in paragraph (b) of this section. (1) Hawaii...

  7. 50 CFR 665.812 - Sea turtle take mitigation measures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 13 2012-10-01 2012-10-01 false Sea turtle take mitigation measures. 665... Pacific Pelagic Fisheries § 665.812 Sea turtle take mitigation measures. (a) Possession and use of... sea turtle handling requirements set forth in paragraph (b) of this section. (1) Hawaii...

  8. 50 CFR 665.812 - Sea turtle take mitigation measures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Sea turtle take mitigation measures. 665... Pacific Pelagic Fisheries § 665.812 Sea turtle take mitigation measures. (a) Possession and use of... sea turtle handling requirements set forth in paragraph (b) of this section. (1) Hawaii...

  9. 50 CFR 665.812 - Sea turtle take mitigation measures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Sea turtle take mitigation measures. 665... Pacific Pelagic Fisheries § 665.812 Sea turtle take mitigation measures. (a) Possession and use of... sea turtle handling requirements set forth in paragraph (b) of this section. (1) Hawaii...

  10. 50 CFR 665.812 - Sea turtle take mitigation measures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 13 2013-10-01 2013-10-01 false Sea turtle take mitigation measures. 665... Pacific Pelagic Fisheries § 665.812 Sea turtle take mitigation measures. (a) Possession and use of... sea turtle handling requirements set forth in paragraph (b) of this section. (1) Hawaii...

  11. FOLLOW-UP RADON MEASUREMENTS IN 14 MITIGATED SCHOOLS

    EPA Science Inventory

    The report gives results of a determination of the long-term performance of radon mitigation systems installed in U. S. EPA research schools: radon measurements were conducted in 14 schools that had been mitigated between 1988 and 1991. The measurements were made between Februar...

  12. 43 CFR 46.130 - Mitigation measures in analyses.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Mitigation measures in analyses. 46.130... Mitigation measures in analyses. (a) Bureau proposed action. The analysis of the proposed action and any alternatives must include an analysis of the effects of the proposed action or alternative as well as...

  13. 43 CFR 46.130 - Mitigation measures in analyses.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Mitigation measures in analyses. 46.130... Mitigation measures in analyses. (a) Bureau proposed action. The analysis of the proposed action and any alternatives must include an analysis of the effects of the proposed action or alternative as well as...

  14. Measuring the Heats of Water.

    ERIC Educational Resources Information Center

    Hunt, James L.; Tegart, Tracy L.

    1994-01-01

    Uses common equipment (tea kettle and vacuum bottles) to precisely measure the specific heat, latent heat of fusion, and latent heat of vaporization of water. Provides descriptions for all three experiments. (MVL)

  15. Fundamentals of heat measurement. [heat flux transducers

    NASA Technical Reports Server (NTRS)

    Gerashchenko, O. A.

    1979-01-01

    Various methods and devices for obtaining experimental data on heat flux density over wide ranges of temperature and pressure are examined. Laboratory tests and device fabrication details are supplemented by theoretical analyses of heat-conduction and thermoelectric effects, providing design guidelines and information relevant to further research and development. A theory defining the measure of correspondence between transducer signal and the measured heat flux is established for individual (isolated) heat flux transducers subject to space and time-dependent loading. An analysis of the properties of stacked (series-connected) transducers of various types (sandwich-type, plane, and spiral) is used to derive a similarity theory providing general governing relationships. The transducers examined are used in 36 types of derivative devices involving direct heat loss measurements, heat conduction studies, radiation pyrometry, calorimetry in medicine and industry and nuclear reactor dosimetry.

  16. Air pollution prevention through urban heat island mitigation: An update on the urban heat island pilot project

    SciTech Connect

    Gorsevski, V.; Taha, H.; Quattrochi, D.; Luvall, J.

    1998-07-01

    Urban heat islands increase the demand for cooling energy and accelerate the formation of smog. They are created when natural vegetation is replaced by heat-absorbing surfaces such as building roofs and walls, parking lots, and streets. Through the implementation of measures designed to mitigate the urban heat island, communities can decrease their demand for energy and effectively cool the metropolitan landscape. In addition to the economic benefits, using less energy leads to reductions in emission of CO{sub 2}--a greenhouse gas--as well as ozone (smog) precursors such as NOx and VOCs. Because ozone is created when NOx and VOCs photochemically combine with heat and solar radiation, actions taken to lower ambient air temperature can significantly reduce ozone concentrations in certain areas. Measures to reverse the urban heat island include afforestation and the widespread use of highly reflective surfaces. To demonstrate the potential benefits of implementing these measures, EPA has teamed up with NASA and LBNL to initiate a pilot project with three US cities. As part of the pilot, NASA will use remotely-sensed data to quantify surface temperature, albedo, the thermal response number and NDVI vegetation of each city. This information will be used by scientists at Lawrence Berkeley National Laboratory (LBNL) along with other data as inputs to model various scenarios that will help quantify the potential benefits of urban heat island mitigation measures in terms of reduced energy use and pollution. This paper will briefly describe this pilot project and provide an update on the progress to date.

  17. Electrostatic particle-in-cell simulation of heat flux mitigation using magnetic fields

    NASA Astrophysics Data System (ADS)

    Lüskow, Karl Felix; Kemnitz, S.; Bandelow, G.; Duras, J.; Kahnfeld, D.; Matthias, P.; Schneider, R.; Konigorski, D.

    2016-10-01

    The particle-in-cell (PIC) method was used to simulate heat flux mitigation experiments with partially ionised argon. The experiments demonstrate the possibility of reducing heat flux towards a target using magnetic fields. Modelling using the PIC method is able to reproduce the heat flux mitigation qualitatively. This is driven by modified electron transport. Electrons are magnetised and react directly to the external magnetic field. In addition, an increase of radial turbulent transport is also needed to explain the experimental observations in the model. Close to the target an increase of electron density is created. Due to quasi-neutrality, ions follow the electrons. Charge exchange collisions couple the dynamics of the neutrals to the ions and reduce the flow velocity of neutrals by radial momentum transport and subsequent losses. By this, the dominant heat-transport channel by neutrals gets reduced and a reduction of the heat deposition, similar to the experiment, is observed. Using the simulation a diagnostic module for optical emission is developed and its results are compared with spectroscopic measurements and photos from the experiment. The results of this study are in good agreement with the experiment. Experimental observations such as a shrank bright emission region close to the nozzle exit, an additional emission in front of the target and an overall change in colour to red are reproduced by the simulation.

  18. Mitigation technologies and measures in energy sector of Kazakstan

    SciTech Connect

    Pilifosova, O.; Danchuk, D.; Temertekov, T.

    1996-12-31

    An important commitment in the UN Framework Convention on Climate Change is to conduct mitigation analysis and to communicate climate change measures and policies. In major part reducing CO{sub 2} as well as the other greenhouse gas emissions in Kazakstan, can be a side-product of measures addressed to increasing energy efficiency. Since such measures are very important for the national economy, mitigation strategies in the energy sector of Kazakstan are directly connected with the general national strategy of the energy sector development. This paper outlines the main measures and technologies in energy sector of Kazakstan which can lead to GHG emissions reduction and presents the results of current mitigation assessment. The mitigation analysis is addressed to energy production sector. A baseline and six mitigation scenarios were developed to evaluate the most attractive mitigation options, focusing on specific technologies which have been already included in sustainable energy programs. According to the baseline projection, Kazakstan`s CO{sub 2} emissions will not exceed their 1990 level until 2005. The potential for CO{sub 2} emission reduction is estimated to be about 11 % of the base line emission level by the end of considered period (in 2020). The main mitigation options in the energy production sector in terms of mitigation potential and technical and economical feasibility include rehabilitation of thermal power plants aimed to increasing efficiency, use of nuclear energy and further expansion in the use of hydro energy based on small hydroelectric power plants.

  19. Particle-In-Cell simulation concerning heat-flux mitigation using electromagnetic fields

    NASA Astrophysics Data System (ADS)

    Lüskow, Karl Felix; Duras, Julia; Kemnitz, Stefan; Kahnfeld, Daniel; Matthias, Paul; Bandelow, Gunnas; Schneider, Ralf; Konigorski, Detlev

    2016-10-01

    In space missions enormous amount of money is spent for the thermal protection system for re-entry. To avoid complex materials and save money one idea is to reduce the heat-flux towards the spacecraft. The partially-ionized gas can be controlled by electromagnetic fields. For first-principle tests partially ionized argon flow from an arc-jet was used to measure the heat-flux mitigation created by an external magnetic field. In the successful experiment a reduction of 85% was measured. In this work the Particle-in-Cell (PIC) method was used to simulate this experiment. PIC is able to reproduce the heat flux mitigation qualitatively. The main mechanism is identified as a changed electron transport and by this, modified electron density due to the reaction to the applied magnetic field. Ions follow due to quasi-neutrality and influence then strongly by charge exchange collisions the neutrals dynamics and heat deposition. This work was supported by the German Space Agency DLR through Project 50RS1508.

  20. Utilising green and bluespace to mitigate urban heat island intensity.

    PubMed

    Gunawardena, K R; Wells, M J; Kershaw, T

    2017-04-15

    It has long been recognised that cities exhibit their own microclimate and are typically warmer than the surrounding rural areas. This 'mesoscale' influence is known as the urban heat island (UHI) effect and results largely from modification of surface properties leading to greater absorption of solar radiation, reduced convective cooling and lower water evaporation rates. Cities typically contain less vegetation and bodies of water than rural areas, and existing green and bluespace is often under threat from increasing population densities. This paper presents a meta-analysis of the key ways in which green and bluespace affect both urban canopy- and boundary-layer temperatures, examined from the perspectives of city-planning, urban climatology and climate science. The analysis suggests that the evapotranspiration-based cooling influence of both green and bluespace is primarily relevant for urban canopy-layer conditions, and that tree-dominated greenspace offers the greatest heat stress relief when it is most needed. However, the magnitude and transport of cooling experienced depends on size, spread, and geometry of greenspaces, with some solitary large parks found to offer minimal boundary-layer cooling. Contribution to cooling at the scale of the urban boundary-layer climate is attributed mainly to greenspace increasing surface roughness and thereby improving convection efficiency rather than evaporation. Although bluespace cooling and transport during the day can be substantial, nocturnal warming is highlighted as likely when conditions are most oppressive. However, when both features are employed together they can offer many synergistic ecosystem benefits including cooling. The ways in which green and bluespace infrastructure is applied in future urban growth strategies, particularly in countries expected to experience rapid urbanisation, warrants greater consideration in urban planning policy to mitigate the adverse effects of the UHI and enhance climate

  1. Divertor Heat Flux Mitigation in the National Spherical Torus Experiment

    SciTech Connect

    Soukhanovskii, V A; Maingi, R; Gates, D A; Menard, J E; Paul, S F; Raman, R; Roquemore, A L; Bell, M G; Bell, R E; Boedo, J A; Bush, C E; Kaita, R; Kugel, H W; LeBlanc, B P; Mueller, D

    2008-08-04

    Steady-state handling of divertor heat flux is a critical issue for both ITER and spherical torus-based devices with compact high power density divertors. Significant reduction of heat flux to the divertor plate has been achieved simultaneously with favorable core and pedestal confinement and stability properties in a highly-shaped lower single null configuration in the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40, 557 2000] using high magnetic flux expansion at the divertor strike point and the radiative divertor technique. A partial detachment of the outer strike point was achieved with divertor deuterium injection leading to peak flux reduction from 4-6 MW m{sup -2} to 0.5-2 MW m{sup -2} in small-ELM 0.8-1.0 MA, 4-6 MW neutral beam injection-heated H-mode discharges. A self-consistent picture of outer strike point partial detachment was evident from divertor heat flux profiles and recombination, particle flux and neutral pressure measurements. Analytic scrape-off layer parallel transport models were used for interpretation of NSTX detachment experiments. The modeling showed that the observed peak heat flux reduction and detachment are possible with high radiated power and momentum loss fractions, achievable with divertor gas injection, and nearly impossible to achieve with main electron density, divertor neutral density or recombination increases alone.

  2. Social and ethical perspectives of landslide risk mitigation measures

    NASA Astrophysics Data System (ADS)

    Kalsnes, Bjørn; Vangelsten, Bjørn V.

    2015-04-01

    Landslide risk may be mitigated by use of a wide range of measures. Mitigation and prevention options may include (1) structural measures to reduce the frequency, severity or exposure to the hazard, (2) non-structural measures, such as land-use planning and early warning systems, to reduce the hazard frequency and consequences, and (3) measures to pool and transfer the risks. In a given situation the appropriate system of mitigation measures may be a combination of various types of measures, both structural and non-structural. In the process of choosing mitigation measures for a given landslide risk situation, the role of the geoscientist is normally to propose possible mitigation measures on basis of the risk level and technical feasibility. Social and ethical perspectives are often neglected in this process. However, awareness of the need to consider social as well as ethical issues in the design and management of mitigating landslide risk is rising. There is a growing understanding that technical experts acting alone cannot determine what will be considered the appropriate set of mitigation and prevention measures. Issues such as environment versus development, questions of acceptable risk, who bears the risks and benefits, and who makes the decisions, also need to be addressed. Policymakers and stakeholders engaged in solving environmental risk problems are increasingly recognising that traditional expert-based decision-making processes are insufficient. This paper analyse the process of choosing appropriate mitigation measures to mitigate landslide risk from a social and ethical perspective, considering technical, cultural, economical, environmental and political elements. The paper focus on stakeholder involvement in the decision making process, and shows how making strategies for risk communication is a key for a successful process. The study is supported by case study examples from Norway and Italy. In the Italian case study, three different risk mitigation

  3. Orbiting space debris: Dangers, measurement and mitigation

    NASA Astrophysics Data System (ADS)

    McNutt, Ross T.

    1992-06-01

    Space debris is a growing environmental problem. Accumulation of objects in earth orbit threatens space systems through the possibility of collisions and runaway debris multiplication. The amount of debris in orbit is uncertain due to the lack of information on the population of debris between 1 and 10 centimeters diameter. Collisions with debris even smaller than 1 cm can be catastrophic due to the high orbital velocities involved. Research efforts are under way at NASA, United States Space Command and the Air Force Phillips Laboratory to detect and catalog the debris population in near-earth space. Current international and national laws are inadequate to control the proliferation of space debris. Space debris is a serious problem with large economic, military, technical and diplomatic components. Actions need to be taken now to: determine the full extent of the orbital debris problem; accurately predict the future evolution of the debris population; decide the extent of the debris mitigation procedures required; implement these policies on a global basis via an international treaty. Action must be initiated now, before the loss of critical space systems such as the space shuttle or the space station.

  4. Orbiting space debris: Dangers, measurement, and mitigation

    NASA Astrophysics Data System (ADS)

    McNutt, Ross T.

    1992-01-01

    Space debris is a growing environmental problem. Accumulation of objects in Earth orbit threatens space systems through the possibility of collisions and runaway debris multiplication. The amount of debris in orbit is uncertain due to the lack of information on the population of debris between 1 and 10 centimeters diameter. Collisions with debris even smaller than 1 cm can be catastrophic due to the high orbital velocities involved. Research efforts are under way at NASA, Unites States Space Command and the Air Force Phillips Laboratory to detect and catalog the debris population in near-Earth space. Current international and national laws are inadequate to control the proliferation of space debris. Space debris is a serious problem with large economic, military, technical, and diplomatic components. Actions need to be taken now for the following reasons: determine the full extent of the orbital debris problem; accurately predict the future evolution of the debris population; decide the extent of the debris mitigation procedures required; implement these policies on a global basis via an international treaty. Action must be initiated now, before the the loss of critical space systems such as the Space Shuttle or the Space Station.

  5. A web-based tool for ranking landslide mitigation measures

    NASA Astrophysics Data System (ADS)

    Lacasse, S.; Vaciago, G.; Choi, Y. J.; Kalsnes, B.

    2012-04-01

    As part of the research done in the European project SafeLand "Living with landslide risk in Europe: Assessment, effects of global change, and risk management strategies", a compendium of structural and non-structural mitigation measures for different landslide types in Europe was prepared, and the measures were assembled into a web-based "toolbox". Emphasis was placed on providing a rational and flexible framework applicable to existing and future mitigation measures. The purpose of web-based toolbox is to assist decision-making and to guide the user in the choice of the most appropriate mitigation measures. The mitigation measures were classified into three categories, describing whether the mitigation measures addressed the landslide hazard, the vulnerability or the elements at risk themselves. The measures considered include structural measures reducing hazard and non-structural mitigation measures, reducing either the hazard or the consequences (or vulnerability and exposure of elements at risk). The structural measures include surface protection and control of surface erosion; measures modifying the slope geometry and/or mass distribution; measures modifying surface water regime - surface drainage; measures mo¬difying groundwater regime - deep drainage; measured modifying the mechanical charac¬teristics of unstable mass; transfer of loads to more competent strata; retaining structures (to modify slope geometry and/or to transfer stress to compe¬tent layer); deviating the path of landslide debris; dissipating the energy of debris flows; and arresting and containing landslide debris or rock fall. The non-structural mitigation measures, reducing either the hazard or the consequences: early warning systems; restricting or discouraging construction activities; increasing resistance or coping capacity of elements at risk; relocation of elements at risk; sharing of risk through insurance. The measures are described in the toolbox with fact sheets providing a

  6. An observational urban heat island study: A primary step in heat event mitigation planning in Detroit, MI

    NASA Astrophysics Data System (ADS)

    Oswald, E.; Rood, R. B.; O'Neill, M.; Zhang, K.

    2010-12-01

    Knowledge of the structure and characteristics of urban heat islands (UHIs) is becoming evermore important to public health practitioners and city planners as they attempt to better identify parts of the city that are especially vulnerable and to plan strategies to mitigate heat-related health threats. The spatial structure of UHIs can be investigated in many different manners, but investigation of raw observations can be problematic. From a meteorological point of view, one goal is to map the structure of the urban heat island from routinely-made standard weather observations to a complex urban environment - in effect, a highly localized downscaling. In order to accomplish such a goal, we conducted analysis using a dense network of temporary observation stations, in concert with established observing networks, inside the city of Detroit. In this talk we correlate point-source temperature measurements with relevant spatial attributes (surface imperviousness, proximity to water, etc.) to model the observed temperature patterns. Future work towards mapping heat vulnerability includes co-analysis with spatial data of population adaptive capacity and sensitivity to heat stress.

  7. WEEE flow and mitigating measures in China.

    PubMed

    Yang, Jianxin; Lu, Bin; Xu, Cheng

    2008-01-01

    The research presented in this paper shows that Waste Electrical and Electronic Equipment (WEEE) issues associated with home appliances, such as TV sets, refrigerators, washing machines, air conditioners, and personal computers, are linked in the WEEE flow and recycling systems and are important to matters of public policy and regulation. In this paper, the sources and generation of WEEE in China are identified, and WEEE volumes are calculated. The results show that recycling capacity must increase if the rising quantity of domestic WEEE is to be handled properly. Simultaneously, suitable WEEE treatment will generate large volumes of secondary resources. Environmental problems caused by the existing recycling processes have been investigated in a case study. Problems mainly stem from open burning of plastic-metal parts and from precious metals leaching techniques that utilize acids. The existing WEEE flow at the national level was investigated and described. It became obvious that a considerable amount of obsolete items are stored in homes and offices and have not yet entered the recycling system. The reuse of used appliances has become a high priority for WEEE collectors and dealers because reuse generates higher economic profits than simple material recovery. The results of a cost analysis of WEEE flow shows that management and collection costs significantly influence current WEEE management. Heated discussions are ongoing in political and administrative bodies as to whether extended producer responsibilities policies are promoting WEEE recycling and management. This paper also discusses future challenges and strategies for WEEE management in China.

  8. Orbiting Space Debris: Dangers, Measurement and Mitigation

    DTIC Science & Technology

    1992-06-01

    sure how many undetectable particles the fragmentation of a satellite creates. Actual ground-based tesis have been conducted in an attempt to...conducted by the Jet Propulsion Laboratory lo measure the presence of 0.2 lo 0.5 cm and 0.5 to 2 cm sized debris. The Areclbo radar in Puerto Rico

  9. Modeling effects of urban heat island mitigation strategies on heat-related morbidity: a case study for Phoenix, Arizona, USA.

    PubMed

    Silva, Humberto R; Phelan, Patrick E; Golden, Jay S

    2010-01-01

    A zero-dimensional energy balance model was previously developed to serve as a user-friendly mitigation tool for practitioners seeking to study the urban heat island (UHI) effect. Accordingly, this established model is applied here to show the relative effects of four common mitigation strategies: increasing the overall (1) emissivity, (2) percentage of vegetated area, (3) thermal conductivity, and (4) albedo of the urban environment in a series of percentage increases by 5, 10, 15, and 20% from baseline values. In addition to modeling mitigation strategies, we present how the model can be utilized to evaluate human health vulnerability from excessive heat-related events, based on heat-related emergency service data from 2002 to 2006. The 24-h average heat index is shown to have the greatest correlation to heat-related emergency calls in the Phoenix (Arizona, USA) metropolitan region. The four modeled UHI mitigation strategies, taken in combination, would lead to a 48% reduction in annual heat-related emergency service calls, where increasing the albedo is the single most effective UHI mitigation strategy.

  10. Modeling effects of urban heat island mitigation strategies on heat-related morbidity: a case study for Phoenix, Arizona, USA

    NASA Astrophysics Data System (ADS)

    Silva, Humberto R.; Phelan, Patrick E.; Golden, Jay S.

    2010-01-01

    A zero-dimensional energy balance model was previously developed to serve as a user-friendly mitigation tool for practitioners seeking to study the urban heat island (UHI) effect. Accordingly, this established model is applied here to show the relative effects of four common mitigation strategies: increasing the overall (1) emissivity, (2) percentage of vegetated area, (3) thermal conductivity, and (4) albedo of the urban environment in a series of percentage increases by 5, 10, 15, and 20% from baseline values. In addition to modeling mitigation strategies, we present how the model can be utilized to evaluate human health vulnerability from excessive heat-related events, based on heat-related emergency service data from 2002 to 2006. The 24-h average heat index is shown to have the greatest correlation to heat-related emergency calls in the Phoenix (Arizona, USA) metropolitan region. The four modeled UHI mitigation strategies, taken in combination, would lead to a 48% reduction in annual heat-related emergency service calls, where increasing the albedo is the single most effective UHI mitigation strategy.

  11. Public Response to Community Mitigation Measures for Pandemic Influenza

    PubMed Central

    Koonin, Lisa M.; Benson, John M.; Cetron, Martin S.; Pollard, William E.; Mitchell, Elizabeth W.; Weldon, Kathleen J.; Herrmann, Melissa J.

    2008-01-01

    We report the results of a national survey conducted to help public health officials understand the public’s response to community mitigation interventions for a severe outbreak of pandemic influenza. Survey results suggest that if community mitigation measures are instituted, most respondents would comply with recommendations but would be challenged to do so if their income or job were severely compromised. The results also indicate that community mitigation measures could cause problems for persons with lower incomes and for racial and ethnic minorities. Twenty-four percent of respondents said that they would not have anyone available to take care of them if they became sick with pandemic influenza. Given these results, planning and public engagement will be needed to encourage the public to be prepared. PMID:18439361

  12. What land covers are effective in mitigating a heat island in urban building rooftop?

    NASA Astrophysics Data System (ADS)

    Lee, S.; Ryu, Y.

    2014-12-01

    Since the 20th century, due to the rapid urbanization many urban environment problems have got blossomed and above all heat island has been recognized as an important issue. There are several causes of urban heat island, but land cover change occupies the largest portion of them. Owing to urban expansion, vegetation is changed into asphalt pavements and concrete buildings, which reduces latent heat flux. To mitigate the problems, people enlarge vegetation covers such as planting street trees, making rooftop gardens and constructing parks or install white roofs that feature high albedo on a building. While the white roofs reflect about 70% of solar radiation and absorb less radiation, vegetation has low albedo but cools the air through transpiration and fixes carbon dioxide through photosynthesis. There are some studies concerning which one is more effective to mitigate heat island between the green roof and white roof. This study compares the green roof and white roof and additionally considers carbon fixation that has not been treated in other studies. Furthermore, this study ascertains an efficiency of solar-cell panel that is used for building roof recently. The panel produces electric power but has low albedo which could warm the air. The experiment is conducted at the rooftop in Seoul, Korea and compares green roof (grass), white roof (painted cover), black roof (solar panel) and normal painted roof. Surface temperature and albedo are observed for the four roof types and incoming shortwave, outgoing longwave and carbon flux are measured in green roof solely. In the case of solar panels, the electricity generation is calculated from the incoming radiation. We compute global warming potentials for the four roof types and test which roof type is most effective in reducing global warming potential.

  13. Can stock rotation effectively mitigate EMS medication exposure to excessive heat and cold?

    PubMed

    Brown, Lawrence H; Wojcik, Susan M; Bailey, Leonard C; Tran, Calvin D

    2006-01-01

    The United States Pharmacopeia recently published a general chapter specifically addressing on-ambulance storage of medications, including a suggestion for stock rotation. This study describes the effectiveness of a simple stock rotation strategy in mitigating EMS medication exposure to excessive heat and cold. Previously collected on-ambulance temperature data from 5 US cities were randomly resampled to generate model exposures of 2 days to 6 months duration. The temperature measurements for every other 24-hour period were then set at 20 degrees C to model the rotation of medications into a controlled environment. For each model, we then determined consistency with the official United States Pharmacopeia definition of controlled room temperature. Without stock rotation, excessive heat occurred in 39.9% of the model exposures. With stock rotation, exposures to excessive heat occurred in less than 1% of northern city models and in 2.9% of the central US models. Stock rotation did not reduce heat exposures in the models for southern cities.

  14. 43 CFR 46.130 - Mitigation measures in analyses.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Section 46.130 Public Lands: Interior Office of the Secretary of the Interior IMPLEMENTATION OF THE... ameliorative design elements (including stipulations, conditions, or best management practices), required to... design element(s). The effects of any mitigation measures other than the ameliorative design...

  15. GHG emission mitigation measures and technologies in the Czech Republic

    SciTech Connect

    Tichy, M.

    1996-12-31

    The paper presents a short overview of main results in two fields: projection of GHG emission from energy sector in the Czech Republic and assessment of technologies and options for GHG mitigation. The last part presents an overview of measures that were prepared for potential inclusion to the Czech Climate Change Action Plan.

  16. Priority mitigation measures in non-energy sector in Kazakstan

    SciTech Connect

    Mizina, S.V.; Pilifosova, O.V.; Gossen, E.F.

    1996-12-31

    Fulfilling the Commitments on UN FCCC through the U.S. Country Studies Program, Kazakstan has developed the national GHG Inventory, vulnerability and adaptation assessment and estimated the possibility of mitigation measures in certain sectors. Next step is developing National Climate Change Action Plan. That process includes such major steps as setting priorities in mitigation measures and technologies, their comprehensive evaluation, preparation implementation strategies, developing the procedure of incorporation of the National Action Plan into other development plans and programs. This paper presents programs and measures that can reduce GHG emissions in non-energy sector. Measures in land-use change and forestry, agriculture and coal mining are considered. Current situation in non-energy sector of Kazakstan is discussed. The amount of GHG emissions reduction and cost analysis presented in this paper was developed with the use of IPCC recommendations.

  17. Calculations and Mitigation of THz Mirror Heating at the Jefferson Lab FEL

    SciTech Connect

    G.P. Williams; S.V. Benson; G.H. Biallas; D. Douglas; J.G. Gubeli; G. Neil; Michelle D. Shinn; S. Zhang; O.V. Chubar; P. D. Dumas

    2005-08-21

    Short bunches of electrons in the Jefferson Lab FEL emit multiparticle coherent edge radiation as they enter the dipole prior to the outcoupler mirror. This light is more collimated than synchrotron light and furthermore is modified by interference from the last chicane magnet after the high reflector. This light provides an additional heat load on the outcoupler in a wavelength range it was not designed to handle. We have performed calculations of this effect using a new extension of the Synchrotron Radiation Workshop code which, importantly, takes into account both acceleration and velocity (or Coulomb) terms of the emitted electric field. We have also measured THz properties of some of the mirrors. We show how the addition of a decompression chicane mitigates these problems.

  18. Pulse Mitigation and Heat Transfer Enhancement Techniques. Volume 5. Transient Liquid Movement in Heat Pipe Wicks

    DTIC Science & Technology

    1992-08-01

    pipe wall. This is not likely to be the case in the thin wicks used in most heat pipes unless severe dryout occurs. Eninger [7] studied the capillary...balance on a randomly oriented fibecr. The theoretical model required an empirical constant obtained from the experimental results. Eninger also 6...structure was utilized for this experimpnt. The two-component wick structure was utilized previously by Eninger [7], who was able to measure slight

  19. Conception of Russian launchers buildup and foremost mitigation measures

    NASA Astrophysics Data System (ADS)

    Chekalin, S. V.; Yakovlev, M. V.; Blagun, V. P.; Kulik, S. V.

    2001-10-01

    The report is devoted to the problems of building up the space launch capabilities during the transfer period of forming the Russian space launch capability system (SLCS). While developing the SLCS concept a special attention is being paid to the measures of mitigating man-made space debris population. Russian launch vehicle launches under the federal and commercial programs up to 2015 have been predicted. The measures undertaken in comparison with the obsolete technology of operating SLCS would reduce by more than two times the accumulation of SLV upper stages and boost engines in orbits and basically prevent their in-orbit breakups.

  20. Yeast probiotic supplementation mitigates some of the negative effects of heat stress in feedlot heifers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heat stress (HS) in feedlot cattle can be detrimental to performance, health and profitability; however, utilization of feed additives has the potential to mitigate some of these negative effects. Therefore, this study was designed to determine if supplementation of a combination live yeast and ye...

  1. Cooler paving materials for heat-island mitigation

    SciTech Connect

    Pomerantz, M.; Akbari, H.

    1998-07-01

    Many cities suffer summer daytime temperatures greater than their suburban or rural surroundings. One of the causes of this heat island phenomenon is the absorption of sunlight by dark pavements. In warm climates, the urban heating damages the environment by adding to air-conditioning demand and creating smog. If urban roads, driveways and walkways were paved with light colored, and consequently cooler, materials these penalties would be diminished. However, lighter materials may cost more than the usual asphalt materials, In this report, the dollar value of potential air conditioning and smog savings from lighter pavements is estimated, and compared to the extra cost of such roads. The extra cost is minimized if the lighter-colored coating is applied as a thin layer when normal maintenance is performed. The authors find that, in Los Angeles, increasing the albedo from 0.1 to 0.35, could produce an air-conditioning saving of $0.012/m{sub 2}-yr. and smog savings of about $0.06/m{sub 2}-yr. The present value of these savings, for the 5 year lifetime of the resurfacing, is about 5 times the annual saving, or about $0.36/m{sub 2}. (The particular climate and smog problem clearly influence this result.) Thus one could purchase a cooler material whose extra cost is this amount, with no net expense. If roads are cooler they may also last longer and thus save money.

  2. Mitigation potential of horizontal ground coupled heat pumps for current and future climatic conditions: UK environmental modelling and monitoring studies

    NASA Astrophysics Data System (ADS)

    García González, Raquel; Verhoef, Anne; Vidale, Pier Luigi; Gan, Guohui; Wu, Yupeng; Hughes, Andrew; Mansour, Majdi; Blyth, Eleanor; Finch, Jon; Main, Bruce

    2010-05-01

    model predictions of soil moisture content and soil temperature with measurements at different GCHP locations over the UK. The combined effect of environment dynamics and horizontal GCHP technical properties on long-term GCHP performance will be assessed using a detailed land surface model (JULES: Joint UK Land Environment Simulator, Meteorological Office, UK) with additional equations embedded describing the interaction between GCHP heat exchangers and the surrounding soil. However, a number of key soil physical processes are currently not incorporated in JULES, such as groundwater flow, which, especially in lowland areas, can have an important effect on the heat flow between soil and HE. Furthermore, the interaction between HE and soil may also cause soil vapour and moisture fluxes. These will affect soil thermal conductivity and hence heat flow between the HE and the surrounding soil, which will in turn influence system performance. The project will address these issues. We propose to drive an improved version of JULES (with equations to simulate GCHP exchange embedded), with long-term gridded (1 km) atmospheric, soil and vegetation data (reflecting current and future environmental conditions) to reliably assess the mitigation potential of GCHPs over the entire domain of the UK, where uptake of GCHPs has been low traditionally. In this way we can identify areas that are most suitable for the installation of GCHPs. Only then recommendations can be made to local and regional governments, for example, on how to improve the mitigation potential in less suitable areas by adjusting GCHP configurations or design.

  3. Latent heat sink in soil heat flux measurements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The surface energy balance includes a term for soil heat flux. Soil heat flux is difficult to measure because it includes conduction and convection heat transfer processes. Accurate representation of soil heat flux is an important consideration in many modeling and measurement applications. Yet, the...

  4. The role of one large greenspace in mitigating London's nocturnal urban heat island.

    PubMed

    Doick, Kieron J; Peace, Andrew; Hutchings, Tony R

    2014-09-15

    The term urban heat island (UHI) describes a phenomenon where cities are on average warmer than the surrounding rural area. Trees and greenspaces are recognised for their strong potential to regulate urban air temperatures and combat the UHI. Empirical data is required in the UK to inform predictions on cooling by urban greenspaces and guide planning to maximise cooling of urban populations. We describe a 5-month study to measure the temperature profile of one of central London's large greenspaces and also in an adjacent street to determine the extent to which the greenspace reduced night-time UHI intensity. Statistical modelling displayed an exponential decay in the extent of cooling with increased distance from the greenspace. The extent of cooling ranged from an estimated 20 m on some nights to 440 m on other nights. The mean temperature reduction over these distances was 1.1 °C in the summer months, with a maximum of 4 °C cooling observed on some nights. Results suggest that calculation of London's UHI using Met Stations close to urban greenspace can underestimate 'urban' heat island intensity due to the cooling effect of the greenspace and values could be in the region of 45% higher. Our results lend support to claims that urban greenspace is an important component of UHI mitigation strategies. Lack of certainty over the variables that govern the extent of the greenspace cooling influence indicates that the multifaceted roles of trees and greenspaces in the UK's urban environment merit further consideration.

  5. Mitigation of the tracer impurity accumulation by EC heating in the LHD

    NASA Astrophysics Data System (ADS)

    Tamura, N.; Sudo, S.; Suzuki, C.; Funaba, H.; Nakamura, Y.; Tanaka, K.; Yoshinuma, M.; Ida, K.; The LHD Experiment Group

    2016-11-01

    The mitigation of a tracer impurity accumulation in the core region of high-temperature helical plasma was clearly observed by applying electron cyclotron heating (ECH) in the large helical device (LHD). In the LHD, the accumulation of impurities toward the centre of the plasma has been observed in a high-density regime. In this study, for observing clearly the behaviour of impurity ions in the plasma core, the extrinsic ‘tracer’ impurity was injected into that region by means of a tracer-encapsulated solid pellet (TESPEL). The high-density LHD plasma without ECH definitely shows the strong impurity accumulation, and then it causes the reduction in electron and ion temperatures in the core region. When ECH was applied just after the TESPEL injection, the accumulation of the tracer impurity ions was mitigated. Even after ECH was switched-off, the intensities of the line emissions from the highly-ionized tracer impurity were increased very slightly. The micro-turbulence measurement with a 2-dimensional phase contrast imaging diagnostic during ECH does not support the view that the change in the micro-turbulence would enhance the outward flow (an increase in a diffusive flux, a decrease in an inward convective flux and/or a change the direction of the convective flux from inward to outward) of the impurity ions. Moreover, at this moment, there is no conclusive data regarding a radial electric field measured with a charge exchange spectroscopy diagnostic to support the view that the change in the radial electric field would be attributed to the increment in the outward flow of the impurity ions from the core region of the LHD plasma.

  6. Validation of a Fast-Response Urban Micrometeorological Model to Assess the Performance of Urban Heat Island Mitigation Strategies

    NASA Astrophysics Data System (ADS)

    Nadeau, D.; Girard, P.; Overby, M.; Pardyjak, E.; Stoll, R., II; Willemsen, P.; Bailey, B.; Parlange, M. B.

    2015-12-01

    Urban heat islands (UHI) are a real threat in many cities worldwide and mitigation measures have become a central component of urban planning strategies. Even within a city, causes of UHI vary from one neighborhood to another, mostly due the spatial variability in surface thermal properties, building geometry, anthropogenic heat flux releases and vegetation cover. As a result, the performance of UHI mitigation measures also varies in space. Hence, there is a need to develop a tool to quantify the efficiency of UHI mitigation measures at the neighborhood scale. The objective of this ongoing study is to validate the fast-response micrometeorological model QUIC EnvSim (QES). This model can provide all information required for UHI studies with a fine spatial resolution (up to 0.5m) and short computation time. QES combines QUIC, a CFD-based wind solver and dispersion model, and EnvSim, composed of a radiation model, a land-surface model and a turbulent transport model. Here, high-resolution (1 m) simulations are run over a subset of the École Polytechnique Fédérale de Lausanne (EPFL) campus including complex buildings, various surfaces properties and vegetation. For nearly five months in 2006-07, a dense network of meteorological observations (92 weather stations over 0.1 km2) was deployed over the campus and these unique data are used here as a validation dataset. We present validation results for different test cases (e.g., sunny vs cloudy days, different incoming wind speeds and directions) and explore the effect of a few UHI mitigation strategies on the spatial distribution of near-surface air temperatures. Preliminary results suggest that QES may be a valuable tool in decision-making regarding adaptation of urban planning to UHI.

  7. Assessment of GHG mitigation technology measures in Ukraine

    SciTech Connect

    Raptsoun, N.; Parasiouk, N.

    1996-12-31

    In June 1992 the representatives of 176 countries including Ukraine met in Rio de Janeiro at the UN Conference to coordinate its efforts in protecting and guarding the environment. Signature of the UN Framework Convention on Climate Change by around 150 countries indicates that climate change is potentially a major threat to the world`s environment and economic development. The project {open_quotes}Country Study on Climate Change in Ukraine{close_quotes} coordinated by the Agency for Rational Energy Use and Ecology (ARENIA-ECO) and supported by the US Country Studies Program Support for Climate Change Studies. The aim of the project is to make the information related to climate change in Ukraine available for the world community by using the potential of Ukrainian research institutes for further concerted actions to solve the problem of climate change on the global scale. The project consists of four elements: (1) the development of the GHG Inventory in Ukraine; (2) assessments of ecosystems-vulnerability to climate change and adaptation options; and (3) mitigation options analysis; (4) public education and outreach activities. This paper contains the main results of the third element for the energy and non-energy sectors. Main tasks of the third element were: (1) to select, test and describe or develop the methodology for mitigation options assessment; (2) to analyze the main sources of GHG emissions in Ukraine; (3) to give the macro economic analysis of Ukrainian development and the development of main economical sectors industry, energy, transport, residential, forestry and agriculture; (4) to forecast GHG emissions for different scenarios of the economic development; and (5) to analyze the main measures to mitigate climate change.

  8. Mitigating the effects of measurement noise on Granger causality

    SciTech Connect

    Nalatore, Hariharan; Ding Mingzhou; Rangarajan, Govindan

    2007-03-15

    Computing Granger causal relations among bivariate experimentally observed time series has received increasing attention over the past few years. Such causal relations, if correctly estimated, can yield significant insights into the dynamical organization of the system being investigated. Since experimental measurements are inevitably contaminated by noise, it is thus important to understand the effects of such noise on Granger causality estimation. The first goal of this paper is to provide an analytical and numerical analysis of this problem. Specifically, we show that, due to noise contamination (1) spurious causality between two measured variables can arise and (2) true causality can be suppressed. The second goal of the paper is to provide a denoising strategy to mitigate this problem. Specifically, we propose a denoising algorithm based on the combined use of the Kalman filter theory and the expectation-maximization algorithm. Numerical examples are used to demonstrate the effectiveness of the denoising approach.

  9. Kinematic analysis for the implementation of landslide mitigation measures

    NASA Astrophysics Data System (ADS)

    Delmonaco, Giuseppe; Margottini, Claudio; Spizzichino, Daniele

    2010-05-01

    The present work is finalised at the implementation of a landslide risk mitigation master plan of the ancient citadel of Machu Picchu. After the warning launched in March 2001, by the scientific community on potential collapse of the citadel from a near-disastrous landslide event different studies have been promoted to reconstruct landslide activity and suggest landslide risk mitigation measures for the protection and conservation of Machu Picchu cultural heritage. A site-scale analysis has been implemented following the application and integration of geomechanical classifications, ambient noise measurements and structural and kinematical analysis. The geology of the area is characterized by granitoid bodies that had been emplaced in the axial zones of the main rift system that are now exposed at the highest altitudes, together with country rocks (Precambrian and Lower Paleozoic metamorphics) originally constituting the rift ‘roots'. The bedrock of the Inca citadel of Machu Picchu is mainly composed by granite and subordinately granodiorite. This is mainly located in the lower part of the slopes. Superficially, the granite is jointed in blocks with variable dimensions, promoted by local structural setting. Single blocks vary from 10-1 to about 200 m3. Soil cover, widely outcropping in the area, is mainly composed by individual blocks and subordinately by coarse materials originated by chemical and physical weathering of minerals. Regional tectonic uplift and structural setting rule the general morphological features of the area and as a consequence, landslide type and evolution. Rock falls, rock slides, debris flows and debris slides are the main landslide typologies affecting the citadel slopes. In the last mission in May 2009, elastic and deformation rock parameters have been collected using a passive seismic innovative technique based on natural microtremor measurements and geostructural scan lines elaboration. A landslide zoning of the citadel has been

  10. Atmospheric Effects on InSAR Measurements and Their Mitigation

    PubMed Central

    Ding, Xiao-li; Li, Zhi-wei; Zhu, Jian-jun; Feng, Guang-cai; Long, Jiang-ping

    2008-01-01

    Interferometric Synthetic Aperture Radar (InSAR) is a powerful technology for observing the Earth surface, especially for mapping the Earth's topography and deformations. InSAR measurements are however often significantly affected by the atmosphere as the radar signals propagate through the atmosphere whose state varies both in space and in time. Great efforts have been made in recent years to better understand the properties of the atmospheric effects and to develop methods for mitigating the effects. This paper provides a systematic review of the work carried out in this area. The basic principles of atmospheric effects on repeat-pass InSAR are first introduced. The studies on the properties of the atmospheric effects, including the magnitudes of the effects determined in the various parts of the world, the spectra of the atmospheric effects, the isotropic properties and the statistical distributions of the effects, are then discussed. The various methods developed for mitigating the atmospheric effects are then reviewed, including the methods that are based on PSInSAR processing, the methods that are based on interferogram modeling, and those that are based on external data such as GPS observations, ground meteorological data, and satellite data including those from the MODIS and MERIS. Two examples that use MODIS and MERIS data respectively to calibrate atmospheric effects on InSAR are also given. PMID:27873822

  11. Atmospheric Effects on InSAR Measurements and Their Mitigation.

    PubMed

    Ding, Xiao-Li; Li, Zhi-Wei; Zhu, Jian-Jun; Feng, Guang-Cai; Long, Jiang-Ping

    2008-09-03

    Interferometric Synthetic Aperture Radar (InSAR) is a powerful technology for observing the Earth surface, especially for mapping the Earth's topography and deformations. InSAR measurements are however often significantly affected by the atmosphere as the radar signals propagate through the atmosphere whose state varies both in space and in time. Great efforts have been made in recent years to better understand the properties of the atmospheric effects and to develop methods for mitigating the effects. This paper provides a systematic review of the work carried out in this area. The basic principles of atmospheric effects on repeat-pass InSAR are first introduced. The studies on the properties of the atmospheric effects, including the magnitudes of the effects determined in the various parts of the world, the spectra of the atmospheric effects, the isotropic properties and the statistical distributions of the effects, are then discussed. The various methods developed for mitigating the atmospheric effects are then reviewed, including the methods that are based on PSInSAR processing, the methods that are based on interferogram modeling, and those that are based on external data such as GPS observations, ground meteorological data, and satellite data including those from the MODIS and MERIS. Two examples that use MODIS and MERIS data respectively to calibrate atmospheric effects on InSAR are also given.

  12. Urban heat mitigation by roof surface materials during the East Asian summer monsoon

    NASA Astrophysics Data System (ADS)

    Lee, Seungjoon; Ryu, Youngryel; Jiang, Chongya

    2015-12-01

    Roof surface materials, such as green and white roofs, have attracted attention in their role in urban heat mitigation, and various studies have assessed the cooling performance of roof surface materials during hot and sunny summer seasons. However, summers in the East Asian monsoon climate region are characterized by significant fluctuations in weather events, such as dry periods, heatwaves, and rainy and cloudy days. This study investigated the efficacy of different roof surface materials for heat mitigation, considering the temperatures both at and beneath the surface of the roof covering materials during a summer monsoon in Seoul, Korea. We performed continuous observations of temperature at and beneath the surface of the roof covering materials, and manual observation of albedo and the normalized difference vegetation index for a white roof, two green roofs (grass (Poa pratensis) and sedum (Sedum sarmentosum)), and a reference surface. Overall, the surface temperature of the white roof was significantly lower than that of the grass and sedum roofs (1.1 °C and 1.3 °C), whereas the temperature beneath the surface of the white roof did not differ significantly from that of the grass and sedum roofs during the summer. The degree of cloudiness significantly modified the surface temperature of the white roof compared with that of the grass and sedum roofs, which depended on plant metabolisms. It was difficult for the grass to maintain its cooling ability without adequate watering management. After considering the cooling performance and maintenance efforts for different environmental conditions, we concluded that white roof performed better in urban heat mitigation than grass and sedum during the East Asian summer monsoon. Our findings will be useful in urban heat mitigation in the region.

  13. The Urban Tree as a Tool to Mitigate the Urban Heat Island in Mexico City: A Simple Phenomenological Model.

    PubMed

    Ballinas, Mónica; Barradas, Víctor L

    2016-01-01

    The urban heat island (UHI) is mainly a nocturnal phenomenon, but it also appears during the day in Mexico City. The UHI may affect human thermal comfort, which can influence human productivity and morbidity in the spring/summer period. A simple phenomenological model based on the energy balance was developed to generate theoretical support of UHI mitigation in Mexico City focused on the latent heat flux change by increasing tree coverage to reduce sensible heat flux and air temperature. Half-hourly data of the urban energy balance components were generated in a typical residential/commercial neighborhood of Mexico City and then parameterized using easily measured variables (air temperature, humidity, pressure, and visibility). Canopy conductance was estimated every hour in four tree species, and transpiration was estimated using sap flow technique and parameterized by the envelope function method. Averaged values of net radiation, energy storage, and sensible and latent heat flux were around 449, 224, 153, and 72 W m, respectively. Daily tree transpiration ranged from 3.64 to 4.35 Ld. To reduce air temperature by 1°C in the studied area, 63 large would be required per hectare, whereas to reduce the air temperature by 2°C only 24 large trees would be required. This study suggests increasing tree canopy cover in the city cannot mitigate UHI adequately but requires choosing the most appropriate tree species to solve this problem. It is imperative to include these types of studies in tree selection and urban development planning to adequately mitigate UHI.

  14. Effects of road mortality and mitigation measures on amphibian populations.

    PubMed

    Beebee, Trevor J C

    2013-08-01

    Road mortality is a widely recognized but rarely quantified threat to the viability of amphibian populations. The global extent of the problem is substantial and factors affecting the number of animals killed on highways include life-history traits and landscape features. Secondary effects include genetic isolation due to roads acting as barriers to migration. Long-term effects of roads on population dynamics are often severe and mitigation methods include volunteer rescues and under-road tunnels. Despite the development of methods that reduce road kill in specific locations, especially under-road tunnels and culverts, there is scant evidence that such measures will protect populations over the long term. There also seems little likelihood that funding will be forthcoming to ameliorate the problem at the scale necessary to prevent further population declines.

  15. Uncertainty of Mitigation Measures to Floods in Jeddah, Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Al Saud, M.

    2011-12-01

    As an aspect of the changing climatic conditions and anthropogenic impact; however, floods and torrents have been recently existed in Jeddah, the coastal Saudi city along the Red Sea. Distributed over 28 surface water basins, totaling an area of more than 2500km2, floods cover more than 15% of the area. This is well pronounced in 2009 and 2011, and it was attributed mainly to the torrential rainfall peaks the area witnesses lately. In addition, there is a chaotic urban distribution from the coastal zone to the adjacent mountain chains to the east, where torrential water runs towards the coast. A detailed assessment has been obtained using advanced space tools (e.g. high-resolution satellite images), and the application was carried out on several aspects of these images and at different dates. This was accomplished in combination the applications of geo-spatial systems to induce the mechanism of water flow regime and to identify the major reasons behind the high risk magnitude. Consequently, the geomorphologic and hydrologic parameters for flood occurrence were recognized. In the light of this catastrophic status; however, mitigation measures are rare enough to protect the area under risk. Recently, and after the 2009 and the recurrent 2011 disasters, which were resulted from floods, some mitigation measures have been undertaken and others were proposed. However, there is still uncertainty for an integrated flood control system. This can be viewed from the unsuitability of the selected sites and erroneous applications for flood controls. Besides, there is a lack to: 1) a giant channeling system for the risk area, 2) check dams, 3) ponds for water collection, 4) sediments-fixing controls, 5) traced watercourses. This is in addition to absence of proper legislation to prevent chaotic urban activities along valleys' pathways.

  16. 49 CFR 192.935 - What additional preventive and mitigative measures must an operator take?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false What additional preventive and mitigative measures... STANDARDS Gas Transmission Pipeline Integrity Management § 192.935 What additional preventive and mitigative... those already required by Part 192 to prevent a pipeline failure and to mitigate the consequences of...

  17. Mitigation of heat stress-related complications by a yeast fermentate product.

    PubMed

    Giblot Ducray, Henri Alexandre; Globa, Ludmila; Pustovyy, Oleg; Reeves, Stuart; Robinson, Larry; Vodyanoy, Vitaly; Sorokulova, Iryna

    2016-08-01

    Heat stress results in a multitude of biological and physiological responses which can become lethal if not properly managed. It has been shown that heat stress causes significant adverse effects in both human and animals. Different approaches have been proposed to mitigate the adverse effects caused by heat stress, among which are special diet and probiotics. We characterized the effect of the yeast fermentate EpiCor (EH) on the prevention of heat stress-related complications in rats. We found that increasing the body temperature of animals from 37.1±0.2 to 40.6±0.2°C by exposure to heat (45°C for 25min) resulted in significant morphological changes in the intestine. Villi height and total mucosal thickness decreased in heat-stressed rats pre-treated with PBS in comparison with control animals not exposed to the heat. Oral treatment of rats with EH before heat stress prevented the traumatic effects of heat on the intestine. Changes in intestinal morphology of heat-stressed rats, pre-treated with PBS resulted in significant elevation of lipopolysaccharides (LPS) level in the serum of these animals. Pre-treatment with EH was effective in the prevention of LPS release into the bloodstream of heat-stressed rats. Our study revealed that elevation of body temperature also resulted in a significant increase of the concentration of vesicles released by erythrocytes in rats, pre-treated with PBS. This is an indication of a pathological impact of heat on the erythrocyte structure. Treatment of rats with EH completely protected their erythrocytes from this heat-induced pathology. Finally, exposure to heat stress conditions resulted in a significant increase of white blood cells in rats. In the group of animals pre-treated with EH before heat stress, the white blood cell count remained the same as in non-heated controls. These results showed the protective effect of the EH product in the prevention of complications, caused by heat stress.

  18. Mitigation of biofouling using electromagnetic fields in tubular heat exchangers-condensers cooled by seawater.

    PubMed

    Trueba, Alfredo; García, Sergio; Otero, Félix M

    2014-01-01

    Electromagnetic field (EMF) treatment is presented as an alternative physical treatment for the mitigation of biofouling adhered to the tubes of a heat exchanger-condenser cooled by seawater. During an experimental phase, a fouling biofilm was allowed to grow until experimental variables indicated that its growth had stabilised. Subsequently, EMF treatment was applied to seawater to eliminate the biofilm and to maintain the achieved cleanliness. The results showed that EMFs precipitated ions dissolved in the seawater. As a consequence of the application of EMFs, erosion altered the intermolecular bonding of extracellular polymers, causing the destruction of the biofilm matrix and its detachment from the inner surface of the heat exchanger-condenser tubes. This detachment led to the partial removal of a mature biofilm and a partial recovery of the efficiency lost in the heat transfer process by using a physical treatment that is harmless to the marine environment.

  19. Overview of mitigation policies and measures in the forestry sector

    SciTech Connect

    Sathaye, J.

    1996-12-31

    In this paper the author addresses questions on how the forestry sector can make a contribution to the general problem of greenhouse gases in the environment. Primarily this is in the form of carbon conservation and sequestering. There is a potential land area for conservation and sequestration estimated to be 700 Mha. The total carbon that could be sequestered and conserved globally by 2050 on this land is 60 - 87 GtC. Slowing deforestation, assisting regeneration, forestation and agroforestry are the primary mitigation measures for carbon conservation and sequestration. For long term success, enforcement to halt deforestation has to be accompained by economic and/or other benefits to the deforesters that equal or exceed their current remuneration. Making plantations a significant fuel for utility electricity generation will require higher biomass yields and thermal efficiency matching that of conventional plants. Significant reduction of global carbon emissions requires national governments to institute measures that provide local, national, economic and other benefits while conserving and sequestering carbon.

  20. Human Factors Research for Space Exploration: Measurement, Modeling, and Mitigation

    NASA Technical Reports Server (NTRS)

    Kaiser, Mary K.; Allen, Christopher S.; Barshi, Immanuel; Billman, Dorrit; Holden, Kritina L.

    2010-01-01

    As part of NASA's Human Research Program, the Space Human Factors Engineering Project serves as the bridge between Human Factors research and Human Spaceflight applications. Our goal is to be responsive to the operational community while addressing issues at a sufficient level of abstraction to ensure that our tools and solutions generalize beyond the point design. In this panel, representatives from four of our research domains will discuss the challenges they face in solving current problems while also enabling future capabilities. Historically, engineering-dominated organizations have tended to view good Human Factors (HF) as a desire rather than a requirement in system design and development. Our field has made significant gains in the past decade, however; the Department of Defense, for example, now recognizes Human-System Integration (HSI), of which HF is a component, as an integral part of their divisions hardware acquisition processes. And our own agency was far more accepting of HF/HSI requirements during the most recent vehicle systems definition than in any prior cycle. Nonetheless, HF subject matter experts at NASA often find themselves in catch up mode... coping with legacy systems (hardware and software) and procedures that were designed with little regard for the human element, and too often with an attitude of we can deal with any operator issues during training. Our challenge, then, is to segregate the true knowledge gaps in Space Human Factors from the prior failures to incorporate best (or even good) HF design principles. Further, we strive to extract the overarching core HF issues from the point-design-specific concerns that capture the operators (and managers) attention. Generally, our approach embraces a 3M approach to Human Factors: Measurement, Modeling, and Mitigation. Our first step is to measure human performance, to move from subjective anecdotes to objective, quantified data. Next we model the phenomenon, using appropriate methods in

  1. The impact of green areas in mitigation of urban heat island

    NASA Astrophysics Data System (ADS)

    Zaninovic, Ksenija

    2016-04-01

    In the framework of the project REPUBLICMED (REtroffiting PUBLic spaces in Intelligent MEDiterranean Cities) co-financed by the European Union, the changes in urban structure have to be proposed in order to mitigate the urban heat island in Zadar, Croatia. The intention is to compare thermal perception for selected locations in Zadar in the present situation and after proposed changes in different parts of the year. For that purpose, four days in different seasons were selected. For winter and summer, the days with extreme minimum and maximum temperatures were selected, whilst for spring and autumn the days in the middle of seasons (April and October) with mean temperatures similar to the corresponding mean seasonal temperatures were selected. All selected days were mainly clear or with small cloudiness resulting with maximum solar radiation. The thermal perception was calculated by means of biometeorological index based on energy equilibrium between human body and environment - physiologically equivalent temperature (PET). In the first analysis, daily courses of biometeorological index for selected situations based on hourly data were compared. During warmest parts of the day in summer the thermal perception differs up to 5°C under the tree shadow, while the differences in other seasons are smaller. The second analysis included the differences in the distribution of frequencies of thermal perception in the warmest part of the day (2 p.m.) throughout the year for selected locations. It is performed using meteorological data measured at the meteorological station Zadar in the 30-year climate period 1981-2010. The results have revealed the reduction in the frequency of sensations of hot and very hot (PET > 35°C or 41°C) under the shadow of the trees during summer, at the rate of up to 25% comparing to the situation before modification (without trees).

  2. Probe Measures Fouling As In Heat Exchangers

    NASA Technical Reports Server (NTRS)

    Marner, Wilbur J.; Macdavid, Kenton S.

    1990-01-01

    Combustion deposits reduce transfer of heat. Instrument measures fouling like that on gas side of heat exchanger in direct-fired boiler or heat-recovery system. Heat-flux probe includes tube with embedded meter in outer shell. Combustion gases flow over probe, and fouling accumulates on it, just as fouling would on heat exchanger. Embedded heat-flow meter is sandwich structure in which thin Chromel layers and middle alloy form thermopile. Users determine when fouling approaches unacceptable levels so they schedule cleaning and avoid decreased transfer of heat and increased drop in pressure fouling causes. Avoids cost of premature, unnecessary maintenance.

  3. Mitigating the Urban Heat Island under Climate Change through Urban Management

    NASA Astrophysics Data System (ADS)

    Zhao, L.; Lee, X.; Oleson, K. W.; Schultz, N. M.; Smith, R. B.

    2015-12-01

    The urban heat island (UHI) represents ubiquitous urban warmth compared to surrounding rural areas. This phenomenon, when compounded with future climate warming, will exacerbate heat stress on urban residents who will comprise 70% of the world's population by 2070. At the same time, urban climate adaptation plans have shown great potential for reducing the impacts of global change. In this study, we assess three mitigation strategies, including reflective roofs, green roofs, and street trees, to ameliorate the warming under climate change through both "online" and "offline" methods. The "online" method compares modeling results from a modified urban roof albedo configuration (ALB-MOD) where the roof albedo is raised to a high reflective value to the modeling results from the default configuration (CTRL), both using the Community Earth System Model (CESM). Three pairs of simulations under current climate forcing and two future scenarios (RCP4.5 and RCP8.5) are conducted. The "offline" method uses a surface temperature attribution solution derived previously for partitioning the UHI intensity to assess the efficacy of the mitigation strategies. The "offline" method supplements the "online" method in assessing green roof and street tree strategies, because the current design of CESM does not have explicit vegetation in the urban canopy configuration. The excellent agreement between the "online" and "offline" results confirms the validity of the offline scheme, supporting that the "offline" method can be used to predict the impacts of various urban adaptation strategies for development planning. Results show that albedo management is the most effective and viable way to mitigate UHIs, whereas although green roof and street trees strategies have evaporative cooling effects, the cooling is compensated by vegetation's lower albedo, showing much less effectiveness on UHI mitigation. Although convection efficiency associated with the surface roughness is an important

  4. Climate benefits of changes in agricultural practices in the context of heat wave mitigation

    NASA Astrophysics Data System (ADS)

    Davin, E.; Seneviratne, S. I.; Ciais, P.; Olioso, A.; Wang, T.

    2014-12-01

    About half of the terrestrial biosphere is under direct human influence through land management (i.e., agricultural areas and managed forests). Changing management practices is therefore a promising avenue for climate change mitigation. The mitigation potential arising from changes in land management practices has been mainly evaluated in terms of carbon storage and GHG emissions [2]. On the other hand, these practices can also influence climate by altering the physical properties of the land surface, but these effects have received less attention so far. Here we show that peak temperatures during heat heaves can be attenuated through cropland albedo management [2]. We first present observational evidence that a substantial summer albedo increase can be obtained by switching from conventional to no-till agriculture. Then, using a regional climate model, we investigate the biogeophysical effect of a full conversion to no-till management over Europe. The cooling effect owing to albedo increase under no-till farming appears to be strongly amplified during warm events. This is due to the low cloud cover during these events, thus leading to a more efficient radiative cooling from albedo change. This implies a strong potential of no-till farming to mitigate heat wave impacts. The reduced evaporation associated with the crop residue cover tends to counteract the albedo-induced cooling, but during hot days the albedo effect remains the dominating factor. For heatwave summer days the local cooling effect gained from no-till practice is of the order of 2 degrees. These findings strongly suggest that the biogeophysical effect of management practices should be considered in the design of climate mitigation policies involving land management. References:[1] Smith, P. et al. (2014): Agriculture, Forestry and Other Land Use (AFOLU). In Climate Change 2014: Mitigation of Climate Change. Contribution of Working Group III to the Fifth Assessment Report of the Intergovernmental Panel

  5. Hydraulic analysis of measures for flood mitigation in floodplain

    NASA Astrophysics Data System (ADS)

    Valentova, J.; Valenta, P.; Weyskrabova, L.; Dostal, T.

    2012-04-01

    The question of possible flood control and flood mitigation measures and their effects is still challenging. While the effect of purely technical flood control measures such as dams or levees is sufficiently described by using any of widely spread or more specific models, the effectiveness of close-to-nature ones (river restoration, appropriate land use, landscape structure regeneration, etc.) is not adequately verified and quantified. On that account, the benefits and feasibility of integration of the natural potential of floodplains to absorb and transform flood wave is being discussed. In addition, there are many side benefits of close-to-nature measures which are hard to evaluate and include into decision making processes. This contribution presents a part of the study related to river and floodplain restoration and revitalization measures in catchments and their flood-control effect. In the study the possibilities of using one-dimensional (HEC-RAS) and two-dimensional hydraulic mathematical models (FAST2D, DIFEM2D) of steady and unsteady flow for estimation of transformation effects of a floodplain were compared. The comparison of used models was made with respect to computed results and also to the availability of input data, mathematical stability, processes and accuracy demands and time requirements. The above mentioned methods of hydraulic modelling were applied to three case study localities in the Czech Republic. The parts of river channels and their floodplain differ in terms of morphology, river channel form and training situation and land-use. Case study areas were selected to represent the main types of floodplains within the Czech Republic for their further classification related to flood wave transformation potential. The transformation effect is compared not only for the natural state of the floodplain, but also for various theoretical scenarios in each locality. Keywords Hydraulic modelling, flood control, floodplain, storage capacity, river

  6. 30 CFR 250.223 - What mitigation measures information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What mitigation measures information must accompany the EP? 250.223 Section 250.223 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE... Contents of Exploration Plans (ep) § 250.223 What mitigation measures information must accompany the EP?...

  7. The effectiveness of cool and green roofs as urban heat island mitigation strategies

    NASA Astrophysics Data System (ADS)

    Li, Dan; Bou-Zeid, Elie; Oppenheimer, Michael

    2014-05-01

    Mitigation of the urban heat island (UHI) effect at the city-scale is investigated using the Weather Research and Forecasting (WRF) model in conjunction with the Princeton Urban Canopy Model (PUCM). Specifically, the cooling impacts of green roof and cool (white/high-albedo) roof strategies over the Baltimore-Washington metropolitan area during a heat wave period (7 June-10 June 2008) are assessed using the optimal set-up of WRF-PUCM described in the companion paper by Li and Bou-Zeid (2014). Results indicate that the surface UHI effect (defined based on the urban-rural surface temperature difference) is reduced significantly more than the near-surface UHI effect (defined based on urban-rural 2 m air temperature difference) when these mitigation strategies are adopted. In addition, as the green and cool roof fractions increase, the surface and near-surface UHIs are reduced almost linearly. Green roofs with relatively abundant soil moisture have comparable effect in reducing the surface and near-surface UHIs to cool roofs with an albedo value of 0.7. Significant indirect effects are also observed for both green and cool roof strategies; mainly, the low-level advection of atmospheric moisture from rural areas into urban terrain is enhanced when the fraction of these roofs increases, thus increasing the humidity in urban areas. The additional benefits or penalties associated with modifications of the main physical determinants of green or cool roof performance are also investigated. For green roofs, when the soil moisture is increased by irrigation, additional cooling effect is obtained, especially when the ‘unmanaged’ soil moisture is low. The effects of changing the albedo of cool roofs are also substantial. These results also underline the capabilities of the WRF-PUCM framework to support detailed analysis and diagnosis of the UHI phenomenon, and of its different mitigation strategies.

  8. 'Heat from Above' Heat Capacity Measurements in Liquid He-4

    NASA Technical Reports Server (NTRS)

    Lee, R. A. M.; Chatto, A.; Sergatskov, D. A.; Babkin, A. V.; Boyd, S. T. P.; Churilov, A. M.; McCarson, T. D.; Chui, T. C. P.; Day, P. K.; Dunca, R. V.

    2003-01-01

    We have made heat capacity measurements of superfluid He-4 at temperatures very close to the lambda point, T(sub lambda) , in a constant heat flux, Q, when the helium sample is heated from above. In this configuration the helium enters a self-organized (SOC) heat transport state at a temperature T(sub SOC)(Q), which for Q greater than or = 100 nW/sq cm lies below T(sub lambda). At low Q we observe little or no deviation from the bulk Q = 0 heat capacity up to T(sub SOC)(Q); beyond this temperature the heat capacity appears to be sharply depressed, deviating dramatically from its bulk behaviour. This marks the formation and propagation of a SOC/superfluid two phase state, which we confirm with a simple model. The excellent agreement between data and model serves as an independent confirmation of the existence of the SOC state. As Q is increased (up to 6 micron W/sq cm) we observe a Q dependant depression in the heat capacity that occurs just below T(sub SOC)(Q), when the entire sample is still superfluid. This is due to the emergence of a large thermal resistance in the sample, which we have measured and used to model the observed heat capacity depression. Our measurements of the superfluid thermal resistivity are a factor of ten larger than previous measurements by Baddar et al.

  9. Assessment of human thermal comfort and mitigation measures in different urban climatotopes

    NASA Astrophysics Data System (ADS)

    Müller, N.; Kuttler, W.

    2012-04-01

    This study analyses thermal comfort in the model city of Oberhausen as an example for the densely populated metropolitan region Ruhr, Germany. As thermal loads increase due to climate change negative impacts especially for city dwellers will arise. Therefore mitigation strategies should be developed and considered in urban planning today to prevent future thermal stress. The method consists of the combination of in-situ measurements and numerical model simulations. So in a first step the actual thermal situation is determined and then possible mitigation strategies are derived. A measuring network was installed in eight climatotopes for a one year period recording air temperature, relative humidity, wind speed and wind direction. Based on these parameters the human thermal comfort in terms of physiological equivalent temperature (PET) was calculated by RayMan Pro software. Thus the human comfort of different climatotopes was determined. Heat stress in different land uses varies, so excess thermal loads in urban areas could be detected. Based on the measuring results mitigation strategies were developed, such as increasing areas with high evaporation capacity (green areas and water bodies). These strategies were implemented as different plan scenarios in the microscale urban climate model ENVI-met. The best measure should be identified by comparing the range and effect of these scenarios. Simulations were run in three of the eight climatotopes (city center, suburban and open land site) to analyse the effectiveness of the mitigation strategies in several land use structures. These cover the range of values of all eight climatotopes and therefore provide representative results. In the model area of 21 ha total, the modified section in the different plan scenarios was 1 ha. Thus the effect of small-scale changes could be analysed. Such areas can arise due to population decline and structural changes and hold conversion potential. Emphasis was also laid on analysing the

  10. Modeling of the Urban Heat Island (UHI) using WRF - Assessment of adaptation and mitigation strategies for the city of Stuttgart.

    NASA Astrophysics Data System (ADS)

    Fallmann, Joachim; Suppan, Peter; Emeis, Stefan

    2013-04-01

    Cities are warmer than their surroundings (called urban heat island, UHI). UHI influence urban atmospheric circulation, air quality, and ecological conditions. UHI leads to upward motion and compensating near-surface inflow from the surroundings which import rural trace substances. Chemical and aerosol formation processes are modified due to increased temperature, reduced humidity and modified urban-rural trace substance mixtures. UHIs produce enhanced heat stress for humans, animals and plants, less water availability and modified air quality. Growing cities and Climate Change will aggravate the UHI and its effects and urgently require adaptation and mitigation strategies. Prior to this, UHI properties must be assessed by surface observations, ground- and satellite-based vertical remote sensing and numerical modelling. The Weather Research and Forecasting Model (WRF) is an instrument to simulate and assess this phenomenon based on boundary conditions from observations and global climate models. Three urbanization schemes are available with WRF, which are tested during this study for different weather conditions in central Europe and will be enhanced if necessary. High resolution land use maps are used for this modeling effort. In situ measurements and Landsat thermal images are employed for validation of the results. The study will focus on the city of Stuttgart located in the south western part of Germany that is situated in a caldera-like orographic feature. This municipality has a long tradition in urban climate research and thus is well equipped with climatologic measurement stations. By using Geographical Information Systems (GIS), it is possible to simulate several scenarios for different surface properties. By increasing the albedo of roof and wall layers in the urban canopy model or by replacing urban land use by natural vegetation, simple urban planning strategies can be tested and the effect on urban heat island formation and air quality can be

  11. Using Remote Sensing Data and Research Results for Urban Heat Island Mitigation

    NASA Technical Reports Server (NTRS)

    Estes, Maury; Luvall, Jeffrey

    1999-01-01

    This paper provides information on the characteristics of the urban heat island, research designed to provide the data needed to develop effective urban heat island reduction strategies, and the development of local working groups to develop implementation plans. As background, an overview of research results on the urban heat island phenomenon and the resultant effect on energy usage and air quality will be explored. The use of more reflective roofing materials, paving materials, tree planting, and other initiatives will be explored as a basis for strategies to mitigate urban heat islands and improve the urban environment. Current efforts to use aircraft remote sensing data in Atlanta, Baton Rouge, Sacramento, and Salt Lake City and our work with non-profit organizations designated to lead public education and strategic development efforts will be presented. Efforts to organize working groups comprised of key stakeholders, the process followed in communicating research results, and methodology for soliciting feedback and incorporating ideas into local plans, policies and decision-making will be discussed. Challenges in developing and transferring data products and research results to stakeholders will be presented. It is our ultimate goal that such efforts be integrated into plans and/or decision models that encourage sustainable development.

  12. Find a Radon Test Kit or Measurement and Mitigation Professional

    EPA Pesticide Factsheets

    Find a qualified radon service professional to fix or mitigate your home. If you have questions about a radon, you should contact your state radon contact and/or contact one or both of the two privately-run National Radon Proficiency Programs

  13. Measuring Specific Heats at High Temperatures

    NASA Technical Reports Server (NTRS)

    Vandersande, Jan W.; Zoltan, Andrew; Wood, Charles

    1987-01-01

    Flash apparatus for measuring thermal diffusivities at temperatures from 300 to 1,000 degrees C modified; measures specific heats of samples to accuracy of 4 to 5 percent. Specific heat and thermal diffusivity of sample measured. Xenon flash emits pulse of radiation, absorbed by sputtered graphite coating on sample. Sample temperature measured with thermocouple, and temperature rise due to pulse measured by InSb detector.

  14. Evaluating the effectiveness of flood damage mitigation measures by the application of propensity score matching

    NASA Astrophysics Data System (ADS)

    Hudson, P.; Botzen, W. J. W.; Kreibich, H.; Bubeck, P.; Aerts, J. C. J. H.

    2014-07-01

    The employment of damage mitigation measures (DMMs) by individuals is an important component of integrated flood risk management. In order to promote efficient damage mitigation measures, accurate estimates of their damage mitigation potential are required. That is, for correctly assessing the damage mitigation measures' effectiveness from survey data, one needs to control for sources of bias. A biased estimate can occur if risk characteristics differ between individuals who have, or have not, implemented mitigation measures. This study removed this bias by applying an econometric evaluation technique called propensity score matching (PSM) to a survey of German households along three major rivers that were flooded in 2002, 2005, and 2006. The application of this method detected substantial overestimates of mitigation measures' effectiveness if bias is not controlled for, ranging from nearly EUR 1700 to 15 000 per measure. Bias-corrected effectiveness estimates of several mitigation measures show that these measures are still very effective since they prevent between EUR 6700 and 14 000 of flood damage per flood event. This study concludes with four main recommendations regarding how to better apply propensity score matching in future studies, and makes several policy recommendations.

  15. Evaluating the effectiveness of flood damage mitigation measures by the application of Propensity Score Matching

    NASA Astrophysics Data System (ADS)

    Hudson, P.; Botzen, W. J. W.; Kreibich, H.; Bubeck, P.; Aerts, J. C. J. H.

    2014-01-01

    The employment of damage mitigation measures by individuals is an important component of integrated flood risk management. In order to promote efficient damage mitigation measures, accurate estimates of their damage mitigation potential are required. That is, for correctly assessing the damage mitigation measures' effectiveness from survey data, one needs to control for sources of bias. A biased estimate can occur if risk characteristics differ between individuals who have, or have not, implemented mitigation measures. This study removed this bias by applying an econometric evaluation technique called Propensity Score Matching to a survey of German households along along two major rivers major rivers that were flooded in 2002, 2005 and 2006. The application of this method detected substantial overestimates of mitigation measures' effectiveness if bias is not controlled for, ranging from nearly € 1700 to € 15 000 per measure. Bias-corrected effectiveness estimates of several mitigation measures show that these measures are still very effective since they prevent between € 6700-14 000 of flood damage. This study concludes with four main recommendations regarding how to better apply Propensity Score Matching in future studies, and makes several policy recommendations.

  16. Seebeck Coefficient Measured With Differential Heat Pulses

    NASA Technical Reports Server (NTRS)

    Zoltan, L.; Wood, C.; Stapfer, G.

    1986-01-01

    Common experimental errors reduced because pulse technique suppresses drifts in thermoelectric measurements. Differential-heat-pulse apparatus measures Seebeck coefficient in semiconductors at temperatures up to 1,900 K. Sample heated to measuring temperature in furnace. Ends of sample then differentially heated a few degrees more by lamps. Differential temperature rise and consequent Seebeck voltage measured via thermocouple leads. Because pulse technique used, errors that often arise from long-term drifts in thermoelectric measurements suppressed. Apparatus works with temperature differences of only few degrees, further increasing accuracy of coefficients obtained.

  17. Latent Heating from TRMM Satellite Measurements

    NASA Astrophysics Data System (ADS)

    Tao, W.; Takayabu, Y. N.; Shige, S.; Lang, S. E.; Olson, W. S.

    2012-12-01

    Rainfall production is a fundamental process within the Earth's hydrological cycle because it represents both a principal forcing term in surface water budgets, and its energetics corollary, latent heating, is the principal source of atmospheric diabatic heating. Latent heat release itself is a consequence of phase changes between the vapor, liquid, and frozen states of water. The properties of the vertical distribution of latent heat release modulate large-scale meridional and zonal circulations within the Tropics - as well as modify the energetic efficiencies of mid-latitude weather systems. This paper highlights the retrieval of latent heat release from satellite measurements generated by the Tropical Rainfall Measuring Mission (TRMM) satellite observatory, which was launched in November 1997 as a joint American-Japanese space endeavor. Since then, TRMM measurements have been providing an accurate four-dimensional account of rainfall over the global Tropics and sub-tropics - information which can be used to estimate the space-time structure of latent heating across the Earth's low latitudes. A set of algorithm methodologies has been developed to estimate latent heating based on rain rate profile retrievals obtained from TRMM measurements. These algorithms are briefly described followed by a discussion of the foremost latent heating products that can be generated from them. The investigation then provides an overview of how TRMM-derived latent heating information is currently being used in conjunction with global weather and climate models, concluding with remarks intended to stimulate further research on latent heating retrieval from satellites.

  18. Experimental study designs to improve the evaluation of road mitigation measures for wildlife.

    PubMed

    Rytwinski, Trina; van der Ree, Rodney; Cunnington, Glenn M; Fahrig, Lenore; Findlay, C Scott; Houlahan, Jeff; Jaeger, Jochen A G; Soanes, Kylie; van der Grift, Edgar A

    2015-05-01

    An experimental approach to road mitigation that maximizes inferential power is essential to ensure that mitigation is both ecologically-effective and cost-effective. Here, we set out the need for and standards of using an experimental approach to road mitigation, in order to improve knowledge of the influence of mitigation measures on wildlife populations. We point out two key areas that need to be considered when conducting mitigation experiments. First, researchers need to get involved at the earliest stage of the road or mitigation project to ensure the necessary planning and funds are available for conducting a high quality experiment. Second, experimentation will generate new knowledge about the parameters that influence mitigation effectiveness, which ultimately allows better prediction for future road mitigation projects. We identify seven key questions about mitigation structures (i.e., wildlife crossing structures and fencing) that remain largely or entirely unanswered at the population-level: (1) Does a given crossing structure work? What type and size of crossing structures should we use? (2) How many crossing structures should we build? (3) Is it more effective to install a small number of large-sized crossing structures or a large number of small-sized crossing structures? (4) How much barrier fencing is needed for a given length of road? (5) Do we need funnel fencing to lead animals to crossing structures, and how long does such fencing have to be? (6) How should we manage/manipulate the environment in the area around the crossing structures and fencing? (7) Where should we place crossing structures and barrier fencing? We provide experimental approaches to answering each of them using example Before-After-Control-Impact (BACI) study designs for two stages in the road/mitigation project where researchers may become involved: (1) at the beginning of a road/mitigation project, and (2) after the mitigation has been constructed; highlighting real case

  19. 30 CFR 550.223 - What mitigation measures information must accompany the EP?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... protected species may be incidentally taken by planned exploration activities, you must include mitigation measures designed to avoid or minimize the incidental take of: (1) Threatened and endangered species...

  20. 30 CFR 550.223 - What mitigation measures information must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... protected species may be incidentally taken by planned exploration activities, you must include mitigation measures designed to avoid or minimize the incidental take of: (1) Threatened and endangered species...

  1. Latent Heating from TRMM Satellite Measurements

    NASA Technical Reports Server (NTRS)

    Tao, Wei-Kuo; Smith, E. A.; Adler, R.; Haddad, Z.; Hou, A.; Iguchi, T.; Kakar, R.; Krishnamurti, T.; Kummerow, C.; Lang, S.

    2004-01-01

    Rainfall production is the fundamental variable within the Earth's hydrological cycle because it is both the principal forcing term in surface water budgets and its energetics corollary, latent heating, is the principal source of atmospheric diabatic heating. Latent heat release itself is a consequence of phase changes between the vapor, liquid, and frozen states of water. The properties of the vertical distribution of latent heat release modulate large-scale meridional and zonal circulations within the tropics - as well as modifying the energetic efficiencies of midlatitude weather systems. This paper focuses on the retrieval of latent heat release from satellite measurements generated by the Tropical Rainfall Measuring Mission (TRMM) satellite observatory, which was launched in November 1997 as a joint American-Japanese space endeavor. Since then, TRMM measurements have been providing an accurate four-dimensional account of rainfall over the global tropics and sub-tropics, information which can be used to estimate the space-time structure of latent heating across the Earth's low latitudes. The paper examines how the observed TRMM distribution of rainfall has advanced an understanding of the global water and energy cycle and its consequent relationship to the atmospheric general circulation and climate via latent heat release. A set of algorithm methodologies that are being used to estimate latent heating based on rain rate retrievals from the TRMM observations are described. The characteristics of these algorithms and the latent heating products that can be generated from them are also described, along with validation analyses of the heating products themselves. Finally, the investigation provides an overview of how TRMM-derived latent heating information is currently being used in conjunction with global weather and climate models, concluding with remarks intended to stimulate further research on latent heating retrieval from satellites.

  2. Latent Heating from TRMM Satellite Measurements

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Smith, E.; Olson, W.

    2005-01-01

    Rainfall production is a fundamental process within the Earth;s hydrological cycle because it represents both a principal forcing term in surface water budgets, and its energetics corollary, latent heating, is the principal source of atmospheric diabatic heating. Latent heat release itself is a consequence of phase changes between the vapor, liquid, and frozen states of water. The properties of the vertical distribution of latent heat release modulate large-scale meridional and zonal circulations with the Tropics - as well as modify the energetic efficiencies of mid-latitude weather systems. This paper highlights the retrieval of observatory, which was launched in November 1997 as a joint American-Japanese space endeavor. Since then, TRMM measurements have been providing an accurate four-dimensional amount of rainfall over the global Tropics and sub-tropics - information which can be used to estimate the spacetime structure of latent heating across the Earth's low latitudes. A set of algorithm methodologies has and continues to be developed to estimate latent heating based on rain rate profile retrievals obtained from TRMM measurements. These algorithms are briefly described followed by a discussion of the foremost latent heating products that can be generate from them. The investigation then provides an overview of how TRMM-derived latent heating information is currently being used in conjunction with global weather and climate models, concluding with remarks intended to stimulate further research on latent heating retrieval from satellites.

  3. Identifiability in biobanks: models, measures, and mitigation strategies

    PubMed Central

    Loukides, Grigorios; Benitez, Kathleen; Clayton, Ellen Wright

    2013-01-01

    The collection and sharing of person-specific biospecimens has raised significant questions regarding privacy. In particular, the question of identifiability, or the degree to which materials stored in biobanks can be linked to the name of the individuals from which they were derived, is under scrutiny. The goal of this paper is to review the extent to which biospecimens and affiliated data can be designated as identifiable. To achieve this goal, we summarize recent research in identifiability assessment for DNA sequence data, as well as associated demographic and clinical data, shared via biobanks. We demonstrate the variability of the degree of risk, the factors that contribute to this variation, and potential ways to mitigate and manage such risk. Finally, we discuss the policy implications of these findings, particularly as they pertain to biobank security and access policies. We situate our review in the context of real data sharing scenarios and biorepositories. PMID:21739176

  4. Pyrolytic graphite gauge for measuring heat flux

    NASA Technical Reports Server (NTRS)

    Bunker, Robert C. (Inventor); Ewing, Mark E. (Inventor); Shipley, John L. (Inventor)

    2002-01-01

    A gauge for measuring heat flux, especially heat flux encountered in a high temperature environment, is provided. The gauge includes at least one thermocouple and an anisotropic pyrolytic graphite body that covers at least part of, and optionally encases the thermocouple. Heat flux is incident on the anisotropic pyrolytic graphite body by arranging the gauge so that the gauge surface on which convective and radiative fluxes are incident is perpendicular to the basal planes of the pyrolytic graphite. The conductivity of the pyrolytic graphite permits energy, transferred into the pyrolytic graphite body in the form of heat flux on the incident (or facing) surface, to be quickly distributed through the entire pyrolytic graphite body, resulting in small substantially instantaneous temperature gradients. Temperature changes to the body can thereby be measured by the thermocouple, and reduced to quantify the heat flux incident to the body.

  5. Compact Instruments Measure Heat Potential

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Based in Huntsville, Alabama, AZ Technology Inc. is a woman- and veteran-owned business that offers expertise in electromechanical-optical design and advanced coatings. AZ Technology has received eight Small Business Innovation Research (SBIR) contracts with Marshall Space Flight Center for the development of spectral reflectometers and the measurement of surface thermal properties. The company uses a variety of measurement services and instruments, including the Spectrafire, a portable spectral emissometer it used to assist General Electric with the design of its award-winning Giraffe Warmer for neonatal intensive care units.

  6. Closing the Gap on Measuring Heat Waves

    NASA Astrophysics Data System (ADS)

    Perkins, S. E.; Alexander, L.

    2012-12-01

    Since the 4th IPCC assessment report, the scientific literature has established that anthropogenic climate change encompasses adverse changes in both mean climate conditions and extreme events, such as heat waves. Indeed, the affects of heat waves are felt across many different sectors, and have high economic, human, and physical impacts over many global regions. The spatial and monetary scale of heat wave impacts emphasizes the necessity of measuring and studying such events in an informative manner, which gives justice to the geographical region affected, the communities impacted, and the climatic fields involved. However, due to such wide interest in heat waves, their definition remains broad in describing a period of consecutive days where conditions are excessively hotter than normal. This has allowed for the employment of a plethora of metrics, which are usually unique to a given sector, or do not appropriately describe some of the important features of heat wave events. As such, it is difficult to ascertain a clear message regarding changes in heat waves, both in the observed record and in projections of future climate. This study addresses this issue by developing a multi-index, multi-aspect framework in which to measure heat waves. The methodology was constructed by assessing a wide range of heat wave and heat wave-related indices, both proposed and employed in the scientific literature. The broad implications of the occurrences, frequency and duration of heat waves and respective changes were also highly considered. The resulting indices measure three or more consecutive days where 1) maximum temperature exceeds the 90th percentile (TX90pct); 2) minimum temperature exceeds the 90th percentile (TN90pct); and 3) daily average temperature has a positive excess heat factor (EHF). The 90th percentiles from which TX90pct and TN90pct are calculated are based on 15-day windows for each calendar day, whereas the EHF is based upon two pre-calculated indices that

  7. Effectiveness of mitigation measures with constructed forested wetlands in Maryland

    USGS Publications Warehouse

    Perry, M.C.

    1997-01-01

    Intensive research on six constructed forested wetlands in Central Maryland was conducted in 1993-1996 to determine success of these habitats as functional forested wetlands for wildlife. Areas studied ranged in size from 2 to 35 acres and were constructed by private companies under contract with three mitigation agencies. Adjacent natural forested wetlands were used as reference sites where similar data were collected. Based on data from the first four years of this study it appears that it will take 35-50 years before these areas have forested wetland vegetation and wildlife similar to that found on mature forested wetlands. This long-time period is based on the high mortality and slow growth of nursery-stock trees and shrubs transplanted on the areas. Mortality and slow growth resulted mostly from excessive surface water on the sites. The level of ground water did not appear to be a factor in regard to transplant mortality. Green ash was the woody transplant species that had the least mortality. Sampling of vegetative ground cover with one-meter square quadrats showed the predominance of grasses and herbs. [abridged abstract

  8. Recent Advances in Measurement and Dietary Mitigation of Enteric Methane Emissions in Ruminants

    PubMed Central

    Patra, Amlan K.

    2016-01-01

    Methane (CH4) emission, which is mainly produced during normal fermentation of feeds by the rumen microorganisms, represents a major contributor to the greenhouse gas (GHG) emissions. Several enteric CH4 mitigation technologies have been explored recently. A number of new techniques have also been developed and existing techniques have been improved in order to evaluate CH4 mitigation technologies and prepare an inventory of GHG emissions precisely. The aim of this review is to discuss different CH4 measuring and mitigation technologies, which have been recently developed. Respiration chamber technique is still considered as a gold standard technique due to its greater precision and reproducibility in CH4 measurements. With the adoption of recent recommendations for improving the technique, the SF6 method can be used with a high level of precision similar to the chamber technique. Short-term measurement techniques of CH4 measurements generally invite considerable within- and between-animal variations. Among the short-term measuring techniques, Greenfeed and methane hood systems are likely more suitable for evaluation of CH4 mitigation studies, if measurements could be obtained at different times of the day relative to the diurnal cycle of the CH4 production. Carbon dioxide and CH4 ratio, sniffer, and other short-term breath analysis techniques are more suitable for on farm screening of large number of animals to generate the data of low CH4-producing animals for genetic selection purposes. Different indirect measuring techniques are also investigated in recent years. Several new dietary CH4 mitigation technologies have been explored, but only a few of them are practical and cost-effective. Future research should be directed toward both the medium- and long-term mitigation strategies, which could be utilized on farms to accomplish substantial reductions of CH4 emissions and to profitably reduce carbon footprint of livestock production systems. This review presents

  9. Energy Saving Potentials and Air Quality Benefits of Urban Heat Island Mitigation

    SciTech Connect

    Akbari, Hashem

    2005-08-23

    Urban areas tend to have higher air temperatures than their rural surroundings as a result of gradual surface modifications that include replacing the natural vegetation with buildings and roads. The term ''Urban Heat Island'' describes this phenomenon. The surfaces of buildings and pavements absorb solar radiation and become extremely hot, which in turn warm the surrounding air. Cities that have been ''paved over'' do not receive the benefit of the natural cooling effect of vegetation. As the air temperature rises, so does the demand for air-conditioning (a/c). This leads to higher emissions from power plants, as well as increased smog formation as a result of warmer temperatures. In the United States, we have found that this increase in air temperature is responsible for 5-10% of urban peak electric demand for a/c use, and as much as 20% of population-weighted smog concentrations in urban areas. Simple ways to cool the cities are the use of reflective surfaces (rooftops and pavements) and planting of urban vegetation. On a large scale, the evapotranspiration from vegetation and increased reflection of incoming solar radiation by reflective surfaces will cool a community a few degrees in the summer. As an example, computer simulations for Los Angeles, CA show that resurfacing about two-third of the pavements and rooftops with reflective surfaces and planting three trees per house can cool down LA by an average of 2-3K. This reduction in air temperature will reduce urban smog exposure in the LA basin by roughly the same amount as removing the basin entire onroad vehicle exhaust. Heat island mitigation is an effective air pollution control strategy, more than paying for itself in cooling energy cost savings. We estimate that the cooling energy savings in U.S. from cool surfaces and shade trees, when fully implemented, is about $5 billion per year (about $100 per air-conditioned house).

  10. Are heat waves susceptible to mitigate the expansion of a species progressing with global warming?

    PubMed Central

    Robinet, Christelle; Rousselet, Jérôme; Pineau, Patrick; Miard, Florie; Roques, Alain

    2013-01-01

    A number of organisms, especially insects, are extending their range in response of the increasing trend of warmer temperatures. However, the effects of more frequent climatic anomalies on these species are not clearly known. The pine processionary moth, Thaumetopoea pityocampa, is a forest pest that is currently extending its geographical distribution in Europe in response to climate warming. However, its population density largely decreased in its northern expansion range (near Paris, France) the year following the 2003 heat wave. In this study, we tested whether the 2003 heat wave could have killed a large part of egg masses. First, the local heat wave intensity was determined. Then, an outdoor experiment was conducted to measure the deviation between the temperatures recorded by weather stations and those observed within sun-exposed egg masses. A second experiment was conducted under laboratory conditions to simulate heat wave conditions (with night/day temperatures of 20/32°C and 20/40°C compared to the control treatment 13/20°C) and measure the potential effects of this heat wave on egg masses. No effects were noticed on egg development. Then, larvae hatched from these egg masses were reared under mild conditions until the third instar and no delayed effects on the development of larvae were found. Instead of eggs, the 2003 heat wave had probably affected directly or indirectly the young larvae that were already hatched when it occurred. Our results suggest that the effects of extreme climatic anomalies occurring over narrow time windows are difficult to determine because they strongly depend on the life stage of the species exposed to these anomalies. However, these effects could potentially reduce or enhance the average warming effects. As extreme weather conditions are predicted to become more frequent in the future, it is necessary to disentangle the effects of the warming trend from the effects of climatic anomalies when predicting the response of a

  11. Are heat waves susceptible to mitigate the expansion of a species progressing with global warming?

    PubMed

    Robinet, Christelle; Rousselet, Jérôme; Pineau, Patrick; Miard, Florie; Roques, Alain

    2013-09-01

    A number of organisms, especially insects, are extending their range in response of the increasing trend of warmer temperatures. However, the effects of more frequent climatic anomalies on these species are not clearly known. The pine processionary moth, Thaumetopoea pityocampa, is a forest pest that is currently extending its geographical distribution in Europe in response to climate warming. However, its population density largely decreased in its northern expansion range (near Paris, France) the year following the 2003 heat wave. In this study, we tested whether the 2003 heat wave could have killed a large part of egg masses. First, the local heat wave intensity was determined. Then, an outdoor experiment was conducted to measure the deviation between the temperatures recorded by weather stations and those observed within sun-exposed egg masses. A second experiment was conducted under laboratory conditions to simulate heat wave conditions (with night/day temperatures of 20/32°C and 20/40°C compared to the control treatment 13/20°C) and measure the potential effects of this heat wave on egg masses. No effects were noticed on egg development. Then, larvae hatched from these egg masses were reared under mild conditions until the third instar and no delayed effects on the development of larvae were found. Instead of eggs, the 2003 heat wave had probably affected directly or indirectly the young larvae that were already hatched when it occurred. Our results suggest that the effects of extreme climatic anomalies occurring over narrow time windows are difficult to determine because they strongly depend on the life stage of the species exposed to these anomalies. However, these effects could potentially reduce or enhance the average warming effects. As extreme weather conditions are predicted to become more frequent in the future, it is necessary to disentangle the effects of the warming trend from the effects of climatic anomalies when predicting the response of a

  12. Heat transfer measurements for Stirling machine cylinders

    NASA Technical Reports Server (NTRS)

    Kornhauser, Alan A.; Kafka, B. C.; Finkbeiner, D. L.; Cantelmi, F. C.

    1994-01-01

    The primary purpose of this study was to measure the effects of inflow-produced heat turbulence on heat transfer in Stirling machine cylinders. A secondary purpose was to provide new experimental information on heat transfer in gas springs without inflow. The apparatus for the experiment consisted of a varying-volume piston-cylinder space connected to a fixed volume space by an orifice. The orifice size could be varied to adjust the level of inflow-produced turbulence, or the orifice plate could be removed completely so as to merge the two spaces into a single gas spring space. Speed, cycle mean pressure, overall volume ratio, and varying volume space clearance ratio could also be adjusted. Volume, pressure in both spaces, and local heat flux at two locations were measured. The pressure and volume measurements were used to calculate area averaged heat flux, heat transfer hysteresis loss, and other heat transfer-related effects. Experiments in the one space arrangement extended the range of previous gas spring tests to lower volume ratio and higher nondimensional speed. The tests corroborated previous results and showed that analytic models for heat transfer and loss based on volume ratio approaching 1 were valid for volume ratios ranging from 1 to 2, a range covering most gas springs in Stirling machines. Data from experiments in the two space arrangement were first analyzed based on lumping the two spaces together and examining total loss and averaged heat transfer as a function of overall nondimensional parameter. Heat transfer and loss were found to be significantly increased by inflow-produced turbulence. These increases could be modeled by appropriate adjustment of empirical coefficients in an existing semi-analytic model. An attempt was made to use an inverse, parameter optimization procedure to find the heat transfer in each of the two spaces. This procedure was successful in retrieving this information from simulated pressure-volume data with artificially

  13. Nuclear reactor melt-retention structure to mitigate direct containment heating

    DOEpatents

    Tutu, Narinder K.; Ginsberg, Theodore; Klages, John R.

    1991-01-01

    A light water nuclear reactor melt-retention structure to mitigate the extent of direct containment heating of the reactor containment building. The structure includes a retention chamber for retaining molten core material away from the upper regions of the reactor containment building when a severe accident causes the bottom of the pressure vessel of the reactor to fail and discharge such molten material under high pressure through the reactor cavity into the retention chamber. In combination with the melt-retention chamber there is provided a passageway that includes molten core droplet deflector vanes and has gas vent means in its upper surface, which means are operable to deflect molten core droplets into the retention chamber while allowing high pressure steam and gases to be vented into the upper regions of the containment building. A plurality of platforms are mounted within the passageway and the melt-retention structure to direct the flow of molten core material and help retain it within the melt-retention chamber. In addition, ribs are mounted at spaced positions on the floor of the melt-retention chamber, and grid means are positioned at the entrance side of the retention chamber. The grid means develop gas back pressure that helps separate the molten core droplets from discharged high pressure steam and gases, thereby forcing the steam and gases to vent into the upper regions of the reactor containment building.

  14. CO₂ mitigation measures of power sector and its integrated optimization in China.

    PubMed

    Dai, Pan; Chen, Guang; Zhou, Hao; Su, Meirong; Bao, Haixia

    2012-01-01

    Power sector is responsible for about 40% of the total CO₂ emissions in the world and plays a leading role in climate change mitigation. In this study, measures that lower CO₂ emissions from the supply side, demand side, and power grid are discussed, based on which, an integrated optimization model of CO₂ mitigation (IOCM) is proposed. Virtual energy, referring to energy saving capacity in both demand side and the power grid, together with conventional energy in supply side, is unified planning for IOCM. Consequently, the optimal plan of energy distribution, considering both economic benefits and mitigation benefits, is figured out through the application of IOCM. The results indicate that development of demand side management (DSM) and smart grid can make great contributions to CO₂ mitigation of power sector in China by reducing the CO₂ emissions by 10.02% and 12.59%, respectively, in 2015, and in 2020.

  15. CO2 Mitigation Measures of Power Sector and Its Integrated Optimization in China

    PubMed Central

    Dai, Pan; Chen, Guang; Zhou, Hao; Su, Meirong; Bao, Haixia

    2012-01-01

    Power sector is responsible for about 40% of the total CO2 emissions in the world and plays a leading role in climate change mitigation. In this study, measures that lower CO2 emissions from the supply side, demand side, and power grid are discussed, based on which, an integrated optimization model of CO2 mitigation (IOCM) is proposed. Virtual energy, referring to energy saving capacity in both demand side and the power grid, together with conventional energy in supply side, is unified planning for IOCM. Consequently, the optimal plan of energy distribution, considering both economic benefits and mitigation benefits, is figured out through the application of IOCM. The results indicate that development of demand side management (DSM) and smart grid can make great contributions to CO2 mitigation of power sector in China by reducing the CO2 emissions by 10.02% and 12.59%, respectively, in 2015, and in 2020. PMID:23213305

  16. Modeled and Measured Underwater Sound Isopleths and Implications for Marine Mammal Mitigation in Alaska.

    PubMed

    Aerts, Lisanne A M; Streever, Bill

    2016-01-01

    Before operating air guns in Alaska, industry is usually required to model underwater sound isopleths, some of which have implications for the mitigation and monitoring of potential marine mammal impacts. Field measurements are often required to confirm or revise model predictions. We compared modeled and measured air gun sound isopleths from 2006 to 2012 and found poor agreement. Natural variability in the marine environment, application of precautionary correction factors, and data interpretation in the generation of circular isopleths all contributed to the observed poor agreement. A broader understanding of the realities of modeled and measured underwater sound isopleths will contribute to improved mitigation practices.

  17. Practical issues for using solar-reflective materials to mitigate urban heat islands

    NASA Astrophysics Data System (ADS)

    Bretz, Sarah; Akbari, Hashem; Rosenfeld, Arthur

    Solar-reflective or high-albedo, alternatives to traditionally absorptive urban surfaces such as rooftops and roadways can reduce cooling energy use and improve urban air quality at almost no cost. This paper presents information to support programs that mitigate urban heat islands with solar-reflective surfaces: estimates of the achievable increase in albedo for a variety of surfaces, issues related to the selection of materials and costs and benefits of using them. As an example, we present data for Sacramento, California. In Sacramento, we estimate that 20% of the 96 square mile area is dark roofing and 10% is dark pavement. Based on the change in albedo that is achievable for these surfaces, the overall albedo of Sacramento could be increased by 18%, a change that would produce significant energy savings and increase comfort within the city. Roofing market data indicate which roofing materials should be targeted for incentive programs. In 1995, asphalt shingle was used for over 65% of residential roofing area in the U.S. and 6% of commercial. Built-up roofing was used for about 5% of residential roofing and about 30% of commercial roofing. Single-ply membranes covered about 9% of the residential roofing area and over 30% of the commercial area. White, solar-reflective alternatives are presently available for these roofing materials but a low- first-cost, solar-reflective alternative to asphalt shingles is needed to capture the sloped-roof market. Since incoming solar radiation has a large non-visible component, solar-reflective materials can also be produced in a variety of colors.

  18. MEASUREMENT OF SPECIFIC HEAT CAPACITY OF SALTSTONE

    SciTech Connect

    Harbour, J; Vickie Williams, V

    2008-09-29

    One of the goals of the Saltstone variability study is to identify (and quantify the impact of) the operational and compositional variables that control or influence the important processing and performance properties of Saltstone grout mixtures. The heat capacity of the Saltstone waste form is one of the important properties of Saltstone mixes that was last measured at SRNL in 1997. It is therefore important to develop a core competency for rapid and accurate analysis of the specific heat capacity of the Saltstone mixes in order to quantify the impact of compositional and operational variations on this property as part of the variability study. The heat capacity, coupled with the heat of hydration data obtained from isothermal calorimetry for a given Saltstone mix, can be used to predict the maximum temperature increase in the cells within the vaults of the Saltstone Disposal Facility (SDF). The temperature increase controls the processing rate and the pour schedule. The maximum temperature is also important to the performance properties of the Saltstone. For example, in mass pours of concrete or grout of which Saltstone is an example, the maximum temperature increase and the maximum temperature difference (between the surface and the hottest location) are controlled to ensure durability of the product and prevent or limit the cracking caused by the thermal gradients produced during curing. This report details the development and implementation of a method for the measurement of the heat capacities of Saltstone mixes as well as the heat capacities of the cementitious materials of the premix and the simulated salt solutions used to batch the mixes. The developed method utilizes the TAM Air isothermal calorimeter and takes advantage of the sophisticated heat flow measurement capabilities of the instrument. Standards and reference materials were identified and used to validate the procedure and ensure accuracy of testing. Heat capacities of Saltstone mixes were

  19. The use of reflective and permeable pavements as a potential practice for heat island mitigation and stormwater management

    NASA Astrophysics Data System (ADS)

    Li, H.; Harvey, J. T.; Holland, T. J.; Kayhanian, M.

    2013-03-01

    To help address the built environmental issues of both heat island and stormwater runoff, strategies that make pavements cooler and permeable have been investigated through measurements and modeling of a set of pavement test sections. The investigation included the hydraulic and thermal performance of the pavements. The permeability results showed that permeable interlocking concrete pavers have the highest permeability (or infiltration rate, ˜0.5 cm s-1). The two permeable asphalt pavements showed the lowest permeability, but still had an infiltration rate of ˜0.1 cm s-1, which is adequate to drain rainwater without generating surface runoff during most typical rain events in central California. An increase in albedo can significantly reduce the daytime high surface temperature in summer. Permeable pavements under wet conditions could give lower surface temperatures than impermeable pavements. The cooling effect highly depends on the availability of moisture near the surface layer and the evaporation rate. The peak cooling effect of watering for the test sections was approximately 15-35 °C on the pavement surface temperature in the early afternoon during summer in central California. The evaporative cooling effect on the pavement surface temperature at 4:00 pm on the third day (25 h after watering) was still 2-7 °C lower compared to that on the second day, without considering the higher air temperature on the third day. A separate and related simulation study performed by UCPRC showed that full depth permeable pavements, if designed properly, can carry both light-duty traffic and certain heavy-duty vehicles while retaining the runoff volume captured from an average California storm event. These preliminarily results indicated the technical feasibility of combined reflective and permeable pavements for addressing the built environment issues related to both heat island mitigation and stormwater runoff management.

  20. Measurement-based auralization methodology for the assessment of noise mitigation measures

    NASA Astrophysics Data System (ADS)

    Thomas, Pieter; Wei, Weigang; Van Renterghem, Timothy; Botteldooren, Dick

    2016-09-01

    The effect of noise mitigation measures is generally expressed by noise levels only, neglecting the listener's perception. In this study, an auralization methodology is proposed that enables an auditive preview of noise abatement measures for road traffic noise, based on the direction dependent attenuation of a priori recordings made with a dedicated 32-channel spherical microphone array. This measurement-based auralization has the advantage that all non-road traffic sounds that create the listening context are present. The potential of this auralization methodology is evaluated through the assessment of the effect of an L-shaped mound. The angular insertion loss of the mound is estimated by using the ISO 9613-2 propagation model, the Pierce barrier diffraction model and the Harmonoise point-to-point model. The realism of the auralization technique is evaluated by listening tests, indicating that listeners had great difficulty in differentiating between a posteriori recordings and auralized samples, which shows the validity of the followed approaches.

  1. Mitigating wildland fire hazard using complex network centrality measures

    NASA Astrophysics Data System (ADS)

    Russo, Lucia; Russo, Paola; Siettos, Constantinos I.

    2016-12-01

    We show how to distribute firebreaks in heterogeneous forest landscapes in the presence of strong wind using complex network centrality measures. The proposed framework is essentially a two-tire one: at the inner part a state-of- the-art Cellular Automata model is used to compute the weights of the underlying lattice network while at the outer part the allocation of the fire breaks is scheduled in terms of a hierarchy of centralities which influence the most the spread of fire. For illustration purposes we applied the proposed framework to a real-case wildfire that broke up in Spetses Island, Greece in 1990. We evaluate the scheme against the benchmark of random allocation of firebreaks under the weather conditions of the real incident i.e. in the presence of relatively strong winds.

  2. Cooperative measures to mitigate Asia-Pacific maritime conflicts.

    SciTech Connect

    Chai, Wen-Chung

    2003-05-01

    The economies of East Asia are predominantly export based and, therefore, place special emphasis on the security of the sea lines of communication (SLOCs). Due to economic globalization, the United States shares these concerns. Cooperative measures by the concerned parties could reduce the potential for disruption by maritime conflicts. Primary threats against the SLOCs are disputes over the resources under the seas, disputes over some small island groups, disputes between particular parties (China-Taiwan and North-South Korea), or illegal activities like smuggling, piracy, or terrorism. This paper provides an overview on these threats, issue by issue, to identify common elements and needed cooperation. Cooperation on other topics such as search and rescue, fisheries protection, and oil spill response may help support improved relations to prevent maritime conflicts. Many technologies can help support maritime cooperation, including improved communications links, tracking and emergency beacon devices, and satellite imaging. Appropriate technical and political means are suggested for each threat to the SLOCs.

  3. Measurement of heat and moisture exchanger efficiency.

    PubMed

    Chandler, M

    2013-09-01

    Deciding between a passive heat and moisture exchanger or active humidification depends upon the level of humidification that either will deliver. Published international standards dictate that active humidifiers should deliver a minimum humidity of 33 mg.l(-1); however, no such requirement exists, for heat and moisture exchangers. Anaesthetists instead have to rely on information provided by manufacturers, which may not allow comparison of different devices and their clinical effectiveness. I suggest that measurement of humidification efficiency, being the percentage moisture returned and determined by measuring the temperature of the respired gases, should be mandated, and report a modification of the standard method that will allow this to be easily measured. In this study, different types of heat and moisture exchangers for adults, children and patients with a tracheostomy were tested. Adult and paediatric models lost between 6.5 mg.l(-1) and 8.5 mg.l(-1) moisture (corresponding to an efficiency of around 80%); however, the models designed for patients with a tracheostomy lost between 16 mg.l(-1) and 18 mg.l(-1) (60% efficiency). I propose that all heat and moisture exchangers should be tested in this manner and percentage efficiency reported to allow an informed choice between different types and models.

  4. Modeling, measuring, and mitigating instability growth in liner implosions on Z

    NASA Astrophysics Data System (ADS)

    Peterson, Kyle

    2015-11-01

    Electro-thermal instabilities result from non-uniform heating due to temperature dependence in the conductivity of a material. In this talk, we will discuss the role of electro-thermal instabilities on the dynamics of magnetically accelerated implosion systems. We present simulations that show electro-thermal instabilities form immediately after the surface material of a conductor melts and can act as a significant seed to subsequent magneto-Rayleigh-Taylor (MRT) instability growth. We discuss measurement results from experiments performed on Sandia National Laboratories Z accelerator to investigate signatures of electro-thermal instability growth on well-characterized initially solid aluminum or beryllium rods driven with a 20 MA, 100 ns risetime current pulse. These measurements show good agreement with electro-thermal instability simulations and exhibit larger instability growth than can be explained by MRT theory alone. Recent experiments have confirmed simulation predictions of dramatically reduced instability growth in solid metallic rods when thick dielectric coatings are used to mitigate density perturbations arising from the electro-thermal instability. These results provide further evidence that the inherent surface roughness of the target is not the dominant seed for the MRT instability, in contrast with most inertial confinement fusion approaches. These results suggest a new technique for substantially reducing the integral MRT growth in magnetically driven implosions. Indeed, recent results on the Z facility with 100 km/s Al and Be liner implosions show substantially reduced growth. These new results include axially magnetized, CH-coated beryllium liner radiographs in which the inner liner surface is observed to be remarkably straight and uniform at a radius of about 120 microns (convergence ratio ~20). Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under

  5. Biogeophysical benefits of no-till agriculture for mitigating heat wave impacts

    NASA Astrophysics Data System (ADS)

    Davin, Edouard; Seneviratne, Sonia; Ciais, Philippe; Olioso, Albert; Wang, Tao

    2014-05-01

    Changes in agricultural practices are considered a possible option to mitigate climate change[1]. In particular, reducing or suppressing tillage (no-till) may have the potential to sequester carbon in soils, which could help slow global warming[1]. On the other hand, such practices also have a direct effect on regional climate by altering the physical properties of the land surface[2]. These biogeophysical effects, however, are still poorly known. Here we show that no-till management increases the surface albedo of croplands in summer and that the resulting cooling effect is amplified during hot extremes, thus attenuating peak temperatures reached during heatwaves. Using a regional climate model accounting for the observed effects of no-till farming on surface albedo, as well as possible reductions in soil evaporation, we investigate the potential consequences of a full conversion to no-till agriculture in Europe. We find that the summer cooling from cropland albedo increase is strongly amplified during hot summer days, when surface albedo has more impact on the Earth's radiative balance due to clear-sky conditions. The reduced evaporation associated with the crop residue cover tends to counteract the albedo-induced cooling, but during hot days the albedo effect is the dominating factor. For heatwave summer days the local cooling effect gained from no-till practice is of the order of 2 degrees. The identified asymmetric impact of surface albedo change on summer temperature opens new avenues for climate engineering measures targeting high impact events rather than mean climate properties. References: [1] Smith, P., D. Martino, Z. Cai, D. Gwary, H. Janzen, P. Kumar, B. McCarl, S. Ogle, F. O'Mara, C. Rice, B. Scholes, O. Sirotenko (2007): Agriculture. In Climate Change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [B. Metz, O.R. Davidson, P.R. Bosch, R. Dave, L.A. Meyer (eds

  6. 30 CFR 250.254 - What mitigation measures information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What mitigation measures information must accompany the DPP or DOCD? 250.254 Section 250.254 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT... Information Contents of Development and Production Plans (dpp) and Development Operations...

  7. 30 CFR 550.254 - What mitigation measures information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... that protected species may be incidentally taken by planned development and production activities, you must include mitigation measures designed to avoid or minimize that incidental take of: (1) Threatened and endangered species listed under the ESA; and (2) Marine mammals, as appropriate, if you have...

  8. 30 CFR 550.254 - What mitigation measures information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... that protected species may be incidentally taken by planned development and production activities, you must include mitigation measures designed to avoid or minimize that incidental take of: (1) Threatened and endangered species listed under the ESA; and (2) Marine mammals, as appropriate, if you have...

  9. 40 CFR 93.125 - Enforceability of design concept and scope and project-level mitigation and control measures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... written commitments to mitigation measures must be obtained prior to a positive conformity determination... scope and project-level mitigation and control measures. 93.125 Section 93.125 Protection of Environment... measures. (a) Prior to determining that a transportation project is in conformity, the MPO, other...

  10. Measurement of heat conduction through stacked screens.

    PubMed

    Lewis, M A; Kuriyama, T; Kuriyama, F; Radebaugh, R

    1998-01-01

    This paper describes the experimental apparatus for the measurement of heat conduction through stacked screens as well as some experimental results taken with the apparatus. Screens are stacked in a fiberglass-epoxy cylinder, which is 24.4 mm in diameter and 55 mm in length. The cold end of the stacked screens is cooled by a Gifford-McMahon (GM) cryocooler at cryogenic temperature, and the hot end is maintained at room temperature. Heat conduction through the screens is determined from the temperature gradient in a calibrated heat flow sensor mounted between the cold end of the stacked screens and the GM cryocooler. The samples used for these experiments consisted of 400-mesh stainless steel screens, 400-mesh phosphor bronze screens, and two different porosities of 325-mesh stainless steel screens. The wire diameter of the 400-mesh stainless steel and phosphor bronze screens was 25.4 micrometers and the 325-mesh stainless steel screen wire diameters were 22.9 micrometers and 27.9 micrometers. Standard porosity values were used for the experimental data with additional porosity values used on selected experiments. The experimental results showed that the helium gas between each screen enhanced the heat conduction through the stacked screens by several orders of magnitude compared to that in vacuum. The conduction degradation factor is the ratio of actual heat conduction to the heat conduction where the regenerator material is assumed to be a solid rod of the same cross sectional area as the metal fraction of the screen. This factor was about 0.1 for the stainless steel and 0.022 for the phosphor bronze, and almost constant for the temperature range of 40 to 80 K at the cold end.

  11. Measurement of heat conduction through stacked screens

    NASA Technical Reports Server (NTRS)

    Lewis, M. A.; Kuriyama, T.; Kuriyama, F.; Radebaugh, R.

    1998-01-01

    This paper describes the experimental apparatus for the measurement of heat conduction through stacked screens as well as some experimental results taken with the apparatus. Screens are stacked in a fiberglass-epoxy cylinder, which is 24.4 mm in diameter and 55 mm in length. The cold end of the stacked screens is cooled by a Gifford-McMahon (GM) cryocooler at cryogenic temperature, and the hot end is maintained at room temperature. Heat conduction through the screens is determined from the temperature gradient in a calibrated heat flow sensor mounted between the cold end of the stacked screens and the GM cryocooler. The samples used for these experiments consisted of 400-mesh stainless steel screens, 400-mesh phosphor bronze screens, and two different porosities of 325-mesh stainless steel screens. The wire diameter of the 400-mesh stainless steel and phosphor bronze screens was 25.4 micrometers and the 325-mesh stainless steel screen wire diameters were 22.9 micrometers and 27.9 micrometers. Standard porosity values were used for the experimental data with additional porosity values used on selected experiments. The experimental results showed that the helium gas between each screen enhanced the heat conduction through the stacked screens by several orders of magnitude compared to that in vacuum. The conduction degradation factor is the ratio of actual heat conduction to the heat conduction where the regenerator material is assumed to be a solid rod of the same cross sectional area as the metal fraction of the screen. This factor was about 0.1 for the stainless steel and 0.022 for the phosphor bronze, and almost constant for the temperature range of 40 to 80 K at the cold end.

  12. [Emergency measures on drinking water sanitation for mitigation of flood and waterlogging disasters].

    PubMed

    Li, S; Pan, S; Sun, F; Gu, L

    1998-01-01

    This article reports the emergency measures for mitigation during flood and waterlogging disasters to ensure drinking water sanitation and to prevent infectious disease outbreaks. Five preparatory and preventive measures for flood and waterlogging disasters include the construction of dual-purpose water supply installation for ordinary and disaster use, the storage of qualified technicians and materials (or their inventories), and the formulation of predetermination programme for disaster relief, ect.

  13. Nutrient pollution mitigation measures across Europe are resilient under future climate

    NASA Astrophysics Data System (ADS)

    Wade, Andrew; Skeffington, Richard; Couture, Raoul; Erlandsson, Martin; Groot, Simon; Halliday, Sarah; Harezlak, Valesca; Hejzlar, Joseph; Jackson-Blake, Leah; Lepistö, Ahti; Papastergiadou, Eva; Psaltopoulos, Demetrios; Riera, Joan; Rankinen, Katri; Skuras, Dimitris; Trolle, Dennis; Whitehead, Paul; Dunn, Sarah; Bucak, Tuba

    2016-04-01

    The key results from the application of catchment-scale biophysical models to assess the likely effectiveness of nutrient pollution mitigation measures set in the context of projected land management and climate change are presented. The assessment is based on the synthesis of modelled outputs of daily river flow, river and lake nitrogen and phosphorus concentrations, and lake chlorophyll-a, for baseline (1981-2010) and scenario (2031-2060) periods for nine study sites across Europe. Together the nine sites represent a sample of key climate and land management types. The robustness and uncertainty in the daily, seasonal and long-term modelled outputs was assessed prior to the scenario runs. Credible scenarios of land-management changes were provided by social scientists and economists familiar with each study site, whilst likely mitigation measures were derived from local stakeholder consultations and cost-effectiveness assessments. Modelled mitigation options were able to reduce nutrient concentrations, and there was no evidence here that they were less effective under future climate. With less certainty, mitigation options could affect the ecological status of waters at these sites in a positive manner, leading to improvement in Water Framework Directive status at some sites. However, modelled outcomes for sites in southern Europe highlighted that increased evaporation and decreased precipitation will cause much lower flows leading to adverse impacts of river and lake ecology. Uncertainties in the climate models, as represented by three GCM-RCM combinations, did not affect this overall picture much.

  14. Acquisition systems for heat transfer measurement

    SciTech Connect

    De Witt, R.J.

    1983-01-01

    Practical heat transfer data acquisition systems are normally characterized by the need for high-resolution, low-drift, low-speed recording devices. Analog devices such as strip chart or circular recorders and FM analog magnetic tape have excellent resolution and work well when data will be presented in temperature versus time format only and need not be processed further. Digital systems are more complex and require an understanding of the following components: digitizing devices, interface bus types, processor requirements, and software design. This paper discusses all the above components of analog and digital data acquisition, as they are used in current practice. Additional information on thermocouple system analysis will aid the user in developing accurate heat transfer measuring systems.

  15. Mitigation of upward and downward vertical displacement event heat loads with upper or lower massive gas injection in DIII-D

    DOE PAGES

    Hollmann, E. M.; Commaux, N.; Eidietis, N. W.; ...

    2015-10-12

    Intentionally triggered upward and downward vertical displacement events (VDEs) leading to disruptions were pre-emptively mitigated with neon massive gas injection (MGI) coming from either above or below the plasma. Global indicators of disruption mitigation effectiveness (conducted heat loads, radiated power, and vessel motion) do not show a clear improvement when mitigating with the gas jet located closer to the VDE impact area. A clear trend of improved mitigation is observed for earlier MGI timing relative to the VDE impact time. The plasma current channel is seen to lock to a preferential phase during the VDE thermal quench, but this phasemore » is not clearly matched by preliminary attempts to fit to the conducted heat load phase. Finally, clear indications of plasma infra-red emission are observed both before and during the disruptions; this infrared emission can affect calculation of disruption heat loads.« less

  16. Mitigation of upward and downward vertical displacement event heat loads with upper or lower massive gas injection in DIII-D

    SciTech Connect

    Hollmann, E. M.; Commaux, N.; Eidietis, N. W.; Lasnier, C. J.; Moyer, R. A.; Parks, P. B.; Shiraki, D.

    2015-10-12

    Intentionally triggered upward and downward vertical displacement events (VDEs) leading to disruptions were pre-emptively mitigated with neon massive gas injection (MGI) coming from either above or below the plasma. Global indicators of disruption mitigation effectiveness (conducted heat loads, radiated power, and vessel motion) do not show a clear improvement when mitigating with the gas jet located closer to the VDE impact area. A clear trend of improved mitigation is observed for earlier MGI timing relative to the VDE impact time. The plasma current channel is seen to lock to a preferential phase during the VDE thermal quench, but this phase is not clearly matched by preliminary attempts to fit to the conducted heat load phase. Finally, clear indications of plasma infra-red emission are observed both before and during the disruptions; this infrared emission can affect calculation of disruption heat loads.

  17. Mitigation of upward and downward vertical displacement event heat loads with upper or lower massive gas injection in DIII-D

    SciTech Connect

    Hollmann, E. M.; Moyer, R. A.; Commaux, N.; Shiraki, D.; Eidietis, N. W.; Parks, P. B.; Lasnier, C. J.

    2015-10-15

    Intentionally triggered upward and downward vertical displacement events (VDEs) leading to disruptions were pre-emptively mitigated with neon massive gas injection (MGI) coming from either above or below the plasma. Global indicators of disruption mitigation effectiveness (conducted heat loads, radiated power, and vessel motion) do not show a clear improvement when mitigating with the gas jet located closer to the VDE impact area. A clear trend of improved mitigation is observed for earlier MGI timing relative to the VDE impact time. The plasma edge magnetic perturbation is seen to lock to a preferential phase during the VDE thermal quench, but this phase is not clearly matched by preliminary attempts to fit to the conducted heat load phase. Clear indications of plasma infra-red (IR) emission are observed both before and during the disruptions. This IR emission can affect calculation of disruption heat loads; here, the time decay of post-disruption IR signals is used to correct for this effect.

  18. Cost-benefit analysis of alternative LNG vapor-mitigation measures. Topical report, September 14, 1987-January 15, 1991

    SciTech Connect

    Atallah, S.

    1992-06-25

    A generalized methodology is presented for comparing the costs and safety benefits of alternative hazard mitigation measures for a large LNG vapor release. The procedure involves the quantification of the risk to the public before and after the application of LNG vapor mitigation measures. In the study, risk was defined as the product of the annual accident frequency, estimated from a fault tree analysis, and the severity of the accident. Severity was measured in terms of the number of people who may be exposed to 2.5% or higher concentration. The ratios of the annual costs of the various mitigation measures to their safety benefits (as determined by the differences between the risk before and after mitigation measure implementation), were then used to identify the most cost-effective approaches to vapor cloud mitigation.

  19. Understanding Coronal Heating with Emission Measure Distributions

    NASA Technical Reports Server (NTRS)

    Klimchik, James A.; Tripathi, Durgesh; Bradshaw, Stephen J.; Mason, Helen E.

    2011-01-01

    It is widely believed that the cross-field spatial scale of coronal heating is small, so that the fundamental plasma structures (loop strands) are spatially unresolved. We therefore must appeal to diagnostic techniques that are not strongly affected by spatial averaging. One valuable observable is the emission measure distribution, EM(T), which indicates how much material is present at each temperature. Using data from the Extreme-ultraviolet Imaging Spectrograph on the Hinode mission, we have determined emission measure distributions in the cores of two active regions. The distributions have power law slopes of approximately 2.4 coolward of the peak. We compare these slopes, as well as the amount of emission measure at very high temperature, with the predictions of a series of models. The models assume impulsive heating (nanoflares) in unresolved strands and take full account of non equilibrium ionization. A variety of nanoflare properties and initial conditions are considered. We also comment on the selection of spectral lines for upcoming missions like Solar Orbiter.

  20. Work measurement in a quantum heat engine

    NASA Astrophysics Data System (ADS)

    Bariani, Francesco; Zhang, Keye; Dong, Ying; Meystre, Pierre

    2015-05-01

    We consider an optomechanical quantum heat engine operating on an Otto cycle for photon-phonon polaritons, the working substance of the engine. We discuss both the average value and quantum fluctuations of its work output, concentrating in particular on the effects of quantum non-adiabaticity due to the finite duration of the cycle. We also determine the quantum back-action of both absorptive and dispersive continuous measurements of the work, and quantify their impact on the Curzon-Ahlborn engine efficiency at maximum power and its fluctuations. We ackowledge financial support from National Basic Research Program of China, NSF, ARO and the DARPA QuaSAR programs

  1. Methane mitigation in cities: how new measurements and partnerships can contribute to emissions reduction strategies

    NASA Astrophysics Data System (ADS)

    Hopkins, F. M.; Bush, S. E.; Ehleringer, J. R.; Lai, C. T.; Rambo, J. P.; Wiggins, E. B.; Miu, J. C. L.; Carranza, V.; Randerson, J. T.

    2014-12-01

    Cities generate a large fraction of anthropogenic methane emissions that are increasing with urbanization and greater reliance on natural gas as fuel. New measurements of methane in cities suggest an as-yet unrealized potential for city-scale methane mitigation. We present high-resolution methane observations from four cities in North America to demonstrate the utility of methane surveys for identifying urban methane sources. We used portable, continuous on-road measurements to determine the spatial distribution of methane in Fairbanks, Los Angeles, Salt Lake City, and San Diego. Across cities, methane tended to be highly concentrated in space, suggesting discrete, point emission sources. Elevated methane levels were found near known emission sources, such as landfills, wastewater treatment facilities, and natural gas-fueled power plants, and revealed the location of fugitive leaks in natural gas infrastructure. The mix of sources and sizes of methane leaks varied among cities, highlighting a need for locally adaptive emissions regulation. Urban methane observations can inform anthropogenic processes in development of methane mitigation strategies. We discuss specific examples of how continuous atmospheric measurements can enhance the design of mitigation strategies in these cities, and potential contributions of these approaches to cross-sectoral efforts to reduce methane emissions at the city level.

  2. Retrieval of Latent Heating from TRMM Measurements

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Smith, E. A.; Adler, R. F.; Hou, A. Y.; Meneghini, R.; Simpson, J.; Haddad, Z. S.; Iguchi, T.; Satoh, S.; Kakar, R.; Krishnamurti, T. N.; Kummerow, C. D.; Lang, S.; Nakamura, K.; Nakazawa, T.; Okamoto, K.; Shige, S.; Olson, W. S.; Takayabu, Y.; Tripoli, G. J.; Yang, S.

    2006-01-01

    Precipitation, in driving the global hydrological cycle, strongly influences the behavior of the Earth's weather and climate systems and is central to their variability. Two-thirds of the global rainfall occurs over the Tropics, which leads to its profound effect on the general circulation of the atmosphere. This is because its energetic equivalent, latent heating (LH), is the tropical convective heat engine's primary fuel source as originally emphasized by Riehl and Malkus (1958). At low latitudes, LH stemming from extended bands of rainfall modulates large-scale zonal and meridional circulations and their consequent mass overturnings (e.g., Hartmann et al. 1984; Hack and Schubert 1990). Also, LH is the principal energy source in the creation, growth, vertical structure, and propagation of long-lived tropical waves (e.g., Puri 1987; Lau and Chan 1988). Moreover, the distinct vertical distribution properties of convective and stratiform LH profiles help influence climatic outcomes via their tight control on large-scale circulations (Lau and Peng 1987; Nakazawa 1988; Sui and Lau 1988; Emanuel et al. 1994; Yanai et al. 2000; Sumi and Nakazawa 2002; Schumacher et al. 2004). The purpose of this paper is to describe how LH profiles are being derived from satellite precipitation rate retrievals, focusing on those being made with Tropical Rainfall Measuring Mission (TRMM) satellite measurements.

  3. Meteorological insights from planetary heat flow measurements

    NASA Astrophysics Data System (ADS)

    Lorenz, Ralph D.

    2015-04-01

    Planetary heat flow measurements are made with a series of high-precision temperature sensors deployed in a column of regolith to determine the geothermal gradient. Such sensors may, however, be susceptible to other influences, especially on worlds with atmospheres. First, pressure fluctuations at the surface may pump air in and out of pore space leading to observable, and otherwise unexpected, temperature fluctuations at depth. Such pumping is important in subsurface radon and methane transport on Earth: evidence of such pumping may inform understanding of methane or water vapor transport on Mars. Second, the subsurface profile contains a muted record of surface temperature history, and such measurements on other worlds may help constrain the extent to which Earth's Little Ice Age was directly solar-forced, versus volcanic-driven and/or amplified by climate feedbacks.

  4. Heat flow calorimeter. [measures output of Ni-Cd batteries

    NASA Technical Reports Server (NTRS)

    Fletcher, J. C.; Johnston, W. V. (Inventor)

    1974-01-01

    Heat flow calorimeter devices are used to measure heat liberated from or absorbed by an object. This device is capable of measuring the thermal output of sealed nickel-cadmium batteries or cells during charge-discharge cycles. An elongated metal heat conducting rod is coupled between the calorimeter vessel and a heat sink, thus providing the only heat exchange path from the calorimeter vessel itself.

  5. Heat Transfer Measurements of Internally Finned Rotating Heat Pipes.

    DTIC Science & Technology

    1983-12-01

    Noncondensable Gases, Rotating Heat Pipe , Performance, Helical and Straight Pin, Internal Heat Transfer Coefficient. AS"RACY (40115111111141 WH ide of* 0686...improvement over the smooth condenser. By helically finning the tube wall in addition to increasing the internal area, the counter-clockwise spiral ... spirally -finned condenser then on the straight-finned condenser. Apparently, during fabrication of the helically -finned condenser, a series of

  6. Micrometeorological simulations to predict the impacts of heat mitigation strategies on pedestrian thermal comfort in a Los Angeles neighborhood

    NASA Astrophysics Data System (ADS)

    Taleghani, Mohammad; Sailor, David; Ban-Weiss, George A.

    2016-02-01

    The urban heat island impacts the thermal comfort of pedestrians in cities. In this paper, the effects of four heat mitigation strategies on micrometeorology and the thermal comfort of pedestrians were simulated for a neighborhood in eastern Los Angeles County. The strategies investigated include solar reflective ‘cool roofs’, vegetative ‘green roofs’, solar reflective ‘cool pavements’, and increased street-level trees. A series of micrometeorological simulations for an extreme heat day were carried out assuming widespread adoption of each mitigation strategy. Comparing each simulation to the control simulation assuming current land cover for the neighborhood showed that additional street-trees and cool pavements reduced 1.5 m air temperature, while cool and green roofs mostly provided cooling at heights above pedestrian level. However, cool pavements increased reflected sunlight from the ground to pedestrians at a set of unshaded receptor locations. This reflected radiation intensified the mean radiant temperature and consequently increased physiological equivalent temperature (PET) by 2.2 °C during the day, reducing the thermal comfort of pedestrians. At another set of receptor locations that were on average 5 m from roadways and underneath preexisting tree cover, cool pavements caused significant reductions in surface air temperatures and small changes in mean radiant temperature during the day, leading to decreases in PET of 1.1 °C, and consequent improvements in thermal comfort. For improving thermal comfort of pedestrians during the afternoon in unshaded locations, adding street trees was found to be the most effective strategy. However, afternoon thermal comfort improvements in already shaded locations adjacent to streets were most significant for cool pavements. Green and cool roofs showed the lowest impact on the thermal comfort of pedestrians since they modify the energy balance at roof level, above the height of pedestrians.

  7. Convex optimization of MRI exposure for mitigation of RF-heating from active medical implants

    NASA Astrophysics Data System (ADS)

    Córcoles, Juan; Zastrow, Earl; Kuster, Niels

    2015-09-01

    Local RF-heating of elongated medical implants during magnetic resonance imaging (MRI) may pose a significant health risk to patients. The actual patient risk depends on various parameters including RF magnetic field strength and frequency, MR coil design, patient’s anatomy, posture, and imaging position, implant location, RF coupling efficiency of the implant, and the bio-physiological responses associated with the induced local heating. We present three constrained convex optimization strategies that incorporate the implant’s RF-heating characteristics, for the reduction of local heating of medical implants during MRI. The study emphasizes the complementary performances of the different formulations. The analysis demonstrates that RF-induced heating of elongated metallic medical implants can be carefully controlled and balanced against MRI quality. A reduction of heating of up to 25 dB can be achieved at the cost of reduced uniformity in the magnitude of the B1+ field of less than 5%. The current formulations incorporate a priori knowledge of clinically-specific parameters, which is assumed to be available. Before these techniques can be applied practically in the broader clinical context, further investigations are needed to determine whether reduced access to a priori knowledge regarding, e.g. the patient’s anatomy, implant routing, RF-transmitter, and RF-implant coupling, can be accepted within reasonable levels of uncertainty.

  8. Convex optimization of MRI exposure for mitigation of RF-heating from active medical implants.

    PubMed

    Córcoles, Juan; Zastrow, Earl; Kuster, Niels

    2015-09-21

    Local RF-heating of elongated medical implants during magnetic resonance imaging (MRI) may pose a significant health risk to patients. The actual patient risk depends on various parameters including RF magnetic field strength and frequency, MR coil design, patient's anatomy, posture, and imaging position, implant location, RF coupling efficiency of the implant, and the bio-physiological responses associated with the induced local heating. We present three constrained convex optimization strategies that incorporate the implant's RF-heating characteristics, for the reduction of local heating of medical implants during MRI. The study emphasizes the complementary performances of the different formulations. The analysis demonstrates that RF-induced heating of elongated metallic medical implants can be carefully controlled and balanced against MRI quality. A reduction of heating of up to 25 dB can be achieved at the cost of reduced uniformity in the magnitude of the B(1)(+) field of less than 5%. The current formulations incorporate a priori knowledge of clinically-specific parameters, which is assumed to be available. Before these techniques can be applied practically in the broader clinical context, further investigations are needed to determine whether reduced access to a priori knowledge regarding, e.g. the patient's anatomy, implant routing, RF-transmitter, and RF-implant coupling, can be accepted within reasonable levels of uncertainty.

  9. Measurement and mitigation of nitrous oxide emissions from a high nitrogen input vegetable system

    NASA Astrophysics Data System (ADS)

    Lam, Shu Kee; Suter, Helen; Davies, Rohan; Bai, Mei; Sun, Jianlei; Chen, Deli

    2015-02-01

    The emission and mitigation of nitrous oxide (N2O) from high nitrogen (N) vegetable systems is not well understood. Nitrification inhibitors are widely used to decrease N2O emissions in many cropping systems. However, most N2O flux measurements and inhibitor impacts have been made with small chambers and have not been investigated at a paddock-scale using micrometeorological techniques. We quantified N2O fluxes over a four ha celery paddock using open-path Fourier Transform Infrared spectroscopy in conjunction with a backward Lagrangian stochastic model, in addition to using a closed chamber technique. The celery crop was grown on a sandy soil in southern Victoria, Australia. The emission of N2O was measured following the application of chicken manure and N fertilizer with and without the application of a nitrification inhibitor 3, 4-dimethyl pyrazole phosphate (DMPP). The two techniques consistently demonstrated that DMPP application reduced N2O emission by 37-44%, even though the N2O fluxes measured by a micrometeorological technique were more than 10 times higher than the small chamber measurements. The results suggest that nitrification inhibitors have the potential to mitigate N2O emission from intensive vegetable production systems, and that the national soil N2O emission inventory assessments and modelling predictions may vary with gas measurement techniques.

  10. Heat transfer measurements of the 1983 kilauea lava flow.

    PubMed

    Hardee, H C

    1983-10-07

    Convective heat flow measurements of a basaltic lava flow were made during the 1983 eruption of Kilauea volcano in Hawaii. Eight field measurements of induced natural convection were made, giving heat flux values that ranged from 1.78 to 8.09 kilowatts per square meter at lava temperatures of 1088 and 1128 degrees Celsius, respectively. These field measurements of convective heat flux at subliquidus temperatures agree with previous laboratory measurements in furnace-melted samples of molten lava, and are useful for predicting heat transfer in magma bodies and for estimating heat extraction rates for magma energy.

  11. Heat-transfer measurements of the 1983 Kilauea lava flow

    SciTech Connect

    Hardee, H.C.

    1983-10-07

    Convective heat flow measurements of a basaltic lava flow were made during the 1983 eruption of Kilauea volcano in Hawaii. Eight field measurements of induced natural convection were made, giving heat flux values that ranged from 1.78 to 8.09 kilowatts per square meter at lava temperatures of 1088 and 1128 degrees Celsius, respectively. These field measurements of convective heat flux at subliquidus temperatures agree with previous laboratory measurements in furnace-melted samples of molten lava, and are useful for predicting heat transfer in magma bodies and for estimating heat extraction rates for magma energy.

  12. Best Practices in Grid Integration of Variable Wind Power: Summary of Recent US Case Study Results and Mitigation Measures

    SciTech Connect

    Smith, J. Charles; Parsons, Brian; Acker, Thomas; Milligan, Michael; Zavidil, Robert; Schuerger, Matthew; DeMeo, Edgar

    2010-01-22

    This paper will summarize results from a number of utility wind integration case studies conducted recently in the US, and outline a number of mitigation measures based on insights from those studies.

  13. Phosphorus losses from agricultural areas in river basins: effects and uncertainties of targeted mitigation measures.

    PubMed

    Kronvang, B; Bechmann, M; Lundekvam, H; Behrendt, H; Rubaek, G H; Schoumans, O F; Syversen, N; Andersen, H E; Hoffmann, C C

    2005-01-01

    In this paper we show the quantitative and relative importance of phosphorus (P) losses from agricultural areas within European river basins and demonstrate the importance of P pathways, linking agricultural source areas to surface water at different scales. Agricultural P losses are increasingly important for the P concentration in most European rivers, lakes, and estuaries, even though the quantity of P lost from agricultural areas in European catchments varies at least one order of magnitude (<0.2 kg P ha(-1) to >2.1 kg P ha(-1)). We focus on the importance of P for the implementation of the EU Water Framework Directive and discuss the benefits, uncertainties, and side effects of the different targeted mitigation measures that can be adopted to combat P losses from agricultural areas in river basins. Experimental evidence of the effects of some of the main targeted mitigation measures hitherto implemented is demonstrated, including: (i) soil tillage changes, (ii) treatment of soils near ditches and streams with iron to reduce P transport from source areas to surface waters, (iii) establishment of buffer zones for retaining P from surface runoff, (iv) restoration of river-floodplain systems to allow natural inundation of riparian areas and deposition of P, and (v) inundation of riparian areas with tile drainage water for P retention. Furthermore, we show how river basin managers can map and analyze the extent and importance of P risk areas, exemplified by four catchments differing in size in Norway, Denmark, and the Netherlands. Finally, we discuss the factors and mechanisms that may delay and/or counteract the responses of mitigation measures for combating P losses from agricultural areas when monitored at the catchment scale.

  14. Zoning and compartmentalisation as risk mitigation measures: an example from poultry production.

    PubMed

    Ratananakorn, L; Wilson, D

    2011-04-01

    This paper discusses the application of compartmentalisation in the Thai commercial poultry industry. The concept was adopted to address Thailand's inability to export fresh poultry meat because of endemic avian influenza. Owing to the nature of compartmentalisation, implementation required a strong partnership between government and the private sector (the Thai poultry exporters). The paper describes the processes implemented to ensure that appropriate risk mitigation measures were in place and to guarantee the continued biosecurity of the compartments. Other Members of the World Organisation for Animal Health may be able to adapt the compartment system used in Thailand to their own similar situations and the formal international recognition of such systems would be beneficial.

  15. Computation, measurement and mitigation of neutral-to-earth potentials on electrical distribution systems

    SciTech Connect

    Dick, W.K.; Winter, D.F.

    1987-04-01

    This paper presents computer generated profiles of primary-neutral-to-earth potentials of electrical distribution systems which incorporate a variety of techniques used to mitigate neutral-to-earth potential (''stray voltage'') at dairy farm facilities. Techniques available to the power supplier and power user include an Electronic Grounding System which provides voltage reduction factors of as much as 200 to 1. A new method of measuring these voltages using a computer data acquisition system which monitors every cycle of the power-frequency voltages on eight totally independent channels for extended periods is described.

  16. Surge Pressure Mitigation in the Global Precipitation Measurement Mission Core Propulsion System

    NASA Technical Reports Server (NTRS)

    Scroggins, Ashley R.; Fiebig, Mark D.

    2014-01-01

    The Global Precipitation Measurement (GPM) mission is an international partnership between NASA and JAXA whose Core spacecraft performs cutting-edge measurements of rainfall and snowfall worldwide and unifies data gathered by a network of precipitation measurement satellites. The Core spacecraft's propulsion system is a blowdown monopropellant system with an initial hydrazine load of 545 kg in a single composite overwrapped propellant tank. At launch, the propulsion system contained propellant in the tank and manifold tubes upstream of the latch valves, with low-pressure helium gas in the manifold tubes downstream of the latch valves. The system had a relatively high beginning-of- life pressure and long downstream manifold lines; these factors created conditions that were conducive to high surge pressures. This paper discusses the GPM project's approach to surge mitigation in the propulsion system design. The paper describes the surge testing program and results, with discussions of specific difficulties encountered. Based on the results of surge testing and pressure drop analyses, a unique configuration of cavitating venturis was chosen to mitigate surge while minimizing pressure losses during thruster maneuvers. This paper concludes with a discussion of overall lessons learned with surge pressure testing for NASA Goddard spacecraft programs.

  17. New debris flow mitigation measures in southern Gansu, China: a case study of the Zhouqu Region

    NASA Astrophysics Data System (ADS)

    Xiong, Muqi; Meng, Xingmin; Li, Yajun

    2014-05-01

    A devastating debris flow occurred in Zhouqu of Gansu Province, China, on 8th August 2010, resulting in a catastrophic disaster, with 1463 people being perished. The debris flow valleys, as other numerous debris valleys in the mountainous region, had preventive engineering constructions, such as check dames, properly designed based on common engineering practices for safe guiding the town located right on the debris flow fan. However, failures of such preventive measures often cause even heavier disasters than those that have no human interactions, as the mitigations give a false safety impression. Given such a weird situation and in order to explore a much more effective disaster prevention strategy against debris flows in the mountainous region, this paper makes a comparative study based on two cases in the area of which one had preventive structures and one hasn't. The result shows that inappropriate mitigation measures that have commonly been applying in the disaster reduction practices in the region are of questionable. It is concluded that going with the nature and following with the natural rules are the best strategy for disaster reduction in the region. Key words: debris flow disasters, disaster reduction strategy, preventive measures

  18. Marine and Hydrokinetic Renewable Energy Devices, Potential Navigational Hazards and Mitigation Measures

    SciTech Connect

    Cool, Richard, M.; Hudon, Thomas, J.; Basco, David, R.; Rondorf, Neil, E.

    2009-12-01

    On April 15, 2008, the Department of Energy (DOE) issued a Funding Opportunity Announcement for Advanced Water Power Projects which included a Topic Area for Marine and Hydrokinetic Renewable Energy Market Acceleration Projects. Within this Topic Area, DOE identified potential navigational impacts of marine and hydrokinetic renewable energy technologies and measures to prevent adverse impacts on navigation as a sub-topic area. DOE defines marine and hydrokinetic technologies as those capable of utilizing one or more of the following resource categories for energy generation: ocean waves; tides or ocean currents; free flowing water in rivers or streams; and energy generation from the differentials in ocean temperature. PCCI was awarded Cooperative Agreement DE-FC36-08GO18177 from the DOE to identify the potential navigational impacts and mitigation measures for marine hydrokinetic technologies. A technical report addressing our findings is available on this Science and Technology Information site under the Product Title, "Marine and Hydrokinetic Renewable Energy Technologies: Potential Navigational Impacts and Mitigation Measures". This product is a brochure, primarily for project developers, that summarizes important issues in that more comprehensive report, identifies locations where that report can be downloaded, and identifies points of contact for more information.

  19. Benthic community recovery from brine impact after the implementation of mitigation measures.

    PubMed

    Del-Pilar-Ruso, Yoana; Martinez-Garcia, Elena; Giménez-Casalduero, Francisca; Loya-Fernández, Angel; Ferrero-Vicente, Luis Miguel; Marco-Méndez, Candela; de-la-Ossa-Carretero, Jose Antonio; Sánchez-Lizaso, José Luis

    2015-03-01

    In many regions, seawater desalination is a growing industry that has its impact on benthic communities. This study analyses the effect on benthic communities of a mitigation measure applied to a brine discharge, using polychaete assemblages as indicator. An eight-year study was conducted at San Pedro del Pinatar (SE Spain) establishing a grid of 12 sites at a depth range of 29-38 m during autumn. Brine discharge started in 2006 and produced a significant decrease in abundance, richness and diversity of polychaete families at the location closest to the discharge, where salinity reached 49. In 2010, a diffuser was deployed at the end of the pipeline in order to increase the mixing, to reduce the impact on benthic communities. After implementation of this mitigation measure, the salinity measured close to discharge was less than 38.5 and a significant recovery in polychaete richness and diversity was detected, to levels similar to those before the discharge. A less evident recovery in abundance was also observed, probably due to different recovery rates of polychaete families. Some families like Paraonidae and Magelonidae were more tolerant to this impact. Others like Syllidae and Capitellidae recovered quickly, although still affected by the discharge, while some families such as Sabellidae and Cirratulidae appeared to recover more slowly.

  20. Mitigating environmental impacts through the energetic use of wood: Regional displacement factors generated by means of substituting non-wood heating systems.

    PubMed

    Wolf, Christian; Klein, Daniel; Richter, Klaus; Weber-Blaschke, Gabriele

    2016-11-01

    Wood biomass, especially when applied for heating, plays an important role for mitigating environmental impacts such as climate change and the transition towards higher shares of renewable energy in today's energy mix. However, the magnitude of mitigation benefits and burdens associated with wood use can vary greatly depending on regional parameters such as the displaced fossil reference or heating mix. Therefore, regionalized displacement factors, considering region-specific production conditions and substituted products are required when assessing the precise contribution of wood biomass towards the mitigation of environmental impacts. We carried out Life Cycle Assessments of wood heating systems for typical Bavarian conditions and substitute energy carriers with a focus on climate change and particulate matter emissions. In order to showcase regional effects, we created weighted displacement factors for the region of Bavaria, based on installed capacities of individual wood heating systems and the harvested tree species distribution. The study reveals that GHG displacements between -57gCO2-eq.∗MJ(-1) of useful energy through the substitution of natural gas with a 15kW spruce pellets heating system and -165gCO2-eq.∗MJ(-1) through the substitution of power utilized for heating with a modern 6kW beech split log heating system can be achieved. It was shown that the GHG mitigation potentials of wood utilization are overestimated through the common use of light fuel oil as the only reference system. We further propose a methodology for the calculation of displacement factors which is adaptable to other regions worldwide. Based on our approach it is possible to generate displacement factors for wood heating systems which enable accurate decision-making for project planning in households, heating plants, communities and also for entire regions.

  1. Green and cool roofs to mitigate urban heat island effects in the Chicago metropolitan area: evaluation with a regional climate model

    NASA Astrophysics Data System (ADS)

    Sharma, A.; Conry, P.; Fernando, H. J. S.; Hamlet, Alan F.; Hellmann, J. J.; Chen, F.

    2016-06-01

    The effects of urban heat islands (UHIs) have a substantial bearing on the sustainability of cities and environs. This paper examines the efficacy of green and cool roofs as potential UHI mitigation strategies to make cities more resilient against UHI. We have employed the urbanized version of the Weather Research and Forecasting (uWRF) model at high (1 km) resolution with physically-based rooftop parameterization schemes (conventional, green and cool), a first-time application to the Chicago metropolitan area. We simulated a hot summer period (16-18 August 2013) and assessed (i) UHI reductions for different urban landuse with green/cool roofs, (ii) the interaction of lake breeze and UHI, and (iii) diurnal boundary layer dynamics. The performance of uWRF was evaluated using sensible heat flux and air temperature measurements from an urban mini-field campaign. The simulated roof surface energy balance captured the energy distribution with respective rooftop algorithms. Results showed that daytime roof temperature reduced and varied linearly with increasing green roof fractions, from less than 1 °C for the case of 25% green roof to ˜3 °C during peak daytime for 100% green roof. Diurnal transitions from land to lake breeze and vice versa had a substantial impact on the daytime cycle of roof surface UHI, which had a 3-4 hour lag in comparison to 2 m UHI. Green and cool roofs reduced horizontal and vertical wind speeds and affected lower atmosphere dynamics, including reduced vertical mixing, lower boundary layer depth, and weaker convective rolls. The lowered wind speeds and vertical mixing during daytime led to stagnation of air near the surface, potentially causing air quality issues. The selection of green and cool roofs for UHI mitigation should therefore carefully consider the competing feedbacks. The new results for regional land-lake circulations and boundary layer dynamics from this study may be extended to other urbanized areas, particularly to coastal

  2. In situ mitigation of subsurface and peripheral focused ion beam damage via simultaneous pulsed laser heating

    SciTech Connect

    Stanford, Michael G.; Lewis, Brett B.; Iberi, Vighter O.; Fowlkes, Jason Davidson; Tan, Shida; Livengood, Rick; Rack, Philip D.

    2016-02-16

    Focused helium and neon ion (He(+)/Ne(+) ) beam processing has recently been used to push resolution limits of direct-write nanoscale synthesis. The ubiquitous insertion of focused He(+) /Ne(+) beams as the next-generation nanofabrication tool-of-choice is currently limited by deleterious subsurface and peripheral damage induced by the energetic ions in the underlying substrate. The in situ mitigation of subsurface damage induced by He(+)/Ne(+) ion exposures in silicon via a synchronized infrared pulsed laser-assisted process is demonstrated. The pulsed laser assist provides highly localized in situ photothermal energy which reduces the implantation and defect concentration by greater than 90%. The laser-assisted exposure process is also shown to reduce peripheral defects in He(+) patterned graphene, which makes this process an attractive candidate for direct-write patterning of 2D materials. In conclusion, these results offer a necessary solution for the applicability of high-resolution direct-write nanoscale material processing via focused ion beams.

  3. In situ mitigation of subsurface and peripheral focused ion beam damage via simultaneous pulsed laser heating

    DOE PAGES

    Stanford, Michael G.; Lewis, Brett B.; Iberi, Vighter O.; ...

    2016-02-16

    Focused helium and neon ion (He(+)/Ne(+) ) beam processing has recently been used to push resolution limits of direct-write nanoscale synthesis. The ubiquitous insertion of focused He(+) /Ne(+) beams as the next-generation nanofabrication tool-of-choice is currently limited by deleterious subsurface and peripheral damage induced by the energetic ions in the underlying substrate. The in situ mitigation of subsurface damage induced by He(+)/Ne(+) ion exposures in silicon via a synchronized infrared pulsed laser-assisted process is demonstrated. The pulsed laser assist provides highly localized in situ photothermal energy which reduces the implantation and defect concentration by greater than 90%. The laser-assisted exposuremore » process is also shown to reduce peripheral defects in He(+) patterned graphene, which makes this process an attractive candidate for direct-write patterning of 2D materials. In conclusion, these results offer a necessary solution for the applicability of high-resolution direct-write nanoscale material processing via focused ion beams.« less

  4. A new modelling framework and mitigation measures for increased resilience to flooding

    NASA Astrophysics Data System (ADS)

    Valyrakis, Manousos; Alexakis, Athanasios; Solley, Mark

    2015-04-01

    Flooding in rivers and estuaries is amongst the most significant challenges our society has yet to tackle effectively. Use of floodwall systems is one of the potential measures that can be used to mitigate the detrimental socio-economical and ecological impacts and alleviate the associated costs of flooding. This work demonstrates the utility of such systems for a case study via appropriate numerical simulations, in addition to conducting scaled flume experiments towards obtaining a better understanding of the performance and efficiency of the flood-wall systems. At first, the results of several characteristic inundation modeling scenarios and flood mitigation options, for a flood-prone region in Scotland. In particular, the history and hydrology of the area are discussed and the assumptions and hydraulic model input (model geometry including instream hydraulic structures -such as bridges and weirs- river and floodplain roughness, initial and boundary conditions) are presented, followed by the model results. Emphasis is given on the potential improvements brought about by mitigating flood risk using flood-wall systems. Further, the implementation of the floodwall in mitigating flood risk is demonstrated via appropriate numerical modeling, utilizing HEC-RAS to simulate the effect of a river's rising stage during a flood event, for a specific area. The later part of this work involves the design, building and utilization of a scaled physical model of a flood-wall system. These experiments are carried out at one of the research flumes in the Water Engineering laboratory of the University of Glasgow. These involve an experimental investigation where the increase of force applied on the floodwall is measured for different degrees of deflection of the water in the stream, under the maximum flow discharge that can be carried through without exceeding the floodwall height (and accounting for the effect of super-elevation). These results can be considered upon the

  5. Heat flux mitigation by impurity seeding in high-field tokamaks

    NASA Astrophysics Data System (ADS)

    Reinke, M. L.

    2017-03-01

    The ability for tokamaks to exhaust power in the boundary via impurity radiation is explored using empirical scalings and a simple 0D exhaust model, focusing on the scaling with toroidal field and major radius. By combining a scaling for the heat flux width and the L-H threshold power, the parallel heat flux in the SOL is shown to scale strongly with magnetic field, {{q}\\parallel}∼ B\\text{T}2.52 while having little to no scaling with machine size, {{q}\\parallel}∼ {{R}0.16} . Despite the increased heat flux at high field, it is shown that target temperatures relevant to detachment can be reached with finite main-ion dilution for a variety of impurity seeding gases, although non-equilibrium ionization balance is required in most cases. The necessary impurity fractions are estimated to scale like {{f}Z}∼ B\\text{T}0.88{{R}1.33} , a result that is facilitated by an increase in upstream temperature at high {{q}\\parallel} relative to peaks in the impurity cooling-curves. This scaling indicates that for optimizing reactors, minimizing device size while maximizing toroidal field, an approach shown to be consistent with energy confinement scaling, will also maximize the feasibility of reaching detachment at the lowest dilution. Despite this, analysis suggests an increase in the impurity fractions relative to existing devices will be required to exhaust power in a reactor-scale tokamak, with validation of impurity radiation physics required before both simple and detailed models can make reliable predictions of absolute f Z .

  6. Laser Measurement Of Convective-Heat-Transfer Coefficient

    NASA Technical Reports Server (NTRS)

    Porro, A. Robert; Hingst, Warren R.; Chriss, Randall M.; Seablom, Kirk D.; Keith, Theo G., Jr.

    1994-01-01

    Coefficient of convective transfer of heat at spot on surface of wind-tunnel model computed from measurements acquired by developmental laser-induced-heat-flux technique. Enables non-intrusive measurements of convective-heat-transfer coefficients at many points across surfaces of models in complicated, three-dimensional, high-speed flows. Measurement spot scanned across surface of model. Apparatus includes argon-ion laser, attenuator/beam splitter electronic shutter infrared camera, and subsystem.

  7. Chemistry control and corrosion mitigation of heat transfer salts for the fluoride salt reactor (FHR)

    SciTech Connect

    Kelleher, B. C.; Sellers, S. R.; Anderson, M. H.; Sridharan, K.; Scheele, R. D.

    2012-07-01

    The Molten Salt Reactor Experiment (MSRE) was a prototype nuclear reactor which operated from 1965 to 1969 at Oak Ridge National Laboratory. The MSRE used liquid fluoride salts as a heat transfer fluid and solvent for fluoride based {sup 235}U and {sup 233}U fuel. Extensive research was performed in order to optimize the removal of oxide and metal impurities from the reactor's heat transfer salt, 2LiF-BeF{sub 2} (FLiBe). This was done by sparging a mixture of anhydrous hydrofluoric acid and hydrogen gas through the FLiBe at elevated temperatures. The hydrofluoric acid reacted with oxides and hydroxides, fluorinating them while simultaneously releasing water vapor. Metal impurities such as iron and chromium were reduced by hydrogen gas and filtered out of the salt. By removing these impurities, the corrosion of reactor components was minimized. The Univ. of Wisconsin - Madison is currently researching a new chemical purification process for fluoride salts that make use of a less dangerous cleaning gas, nitrogen trifluoride. Nitrogen trifluoride has been predicted as a superior fluorinating agent for fluoride salts. These purified salts will subsequently be used for static and loop corrosion tests on a variety of reactor materials to ensure materials compatibility for the new FHR designs. Demonstration of chemistry control methodologies along with potential reduction in corrosion is essential for the use of a fluoride salts in a next generator nuclear reactor system. (authors)

  8. Measurement and Mitigation of the Ionosphere in L-Band Interferometric SAR Data

    NASA Technical Reports Server (NTRS)

    Rosen, Paul A.; Hensley, Scott; Chen, Curtis

    2010-01-01

    Satellite-based repeat-pass Interferometric Synthetic Aperture Radar (InSAR) provides a synoptic high spatial resolution perspective of Earth's changing surface, permitting one to view large areas quickly and efficiently. By measuring relative phase change from one observation to the next on a pixel-by-pixel basis, maps of deformation and change can be derived. Variability of the atmosphere and the ionosphere leads to phase/time delays that are present in the data that can mask many of the subtle deformation signatures of interest, so methods for mitigation of these effects are important. Many of these effects have been observed in existing ALOS PALSAR data, and studies are underway to characterize and mitigate the ionosphere using these data. Since the ionosphere is a dispersive medium, it is possible in principle distinguish the ionospheric signatures from the non-dispersive effects of deformation and the atmosphere. In this paper, we describe a method for mapping the ionosphere in InSAR data based on a multi-frequency split-spectrum processing technique.

  9. Investigation of the impact of climate change on river water temperature: possible mitigation measures using riparian vegetation

    NASA Astrophysics Data System (ADS)

    Weihs, Philipp; Trimmel, Heidelinde; Formayer, Herbert; Kalny, Gerda; Rauch, Hans Peter; Leidinger, David

    2016-04-01

    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 influence the sensitive and latent heat flux. The present study investigates the influence of climate change on water temperature of streams and the potential of riparian vegetation to mitigate its effects. Within the scope of the project BIO_CLIC routine measurements of water temperature at 33 locations alongside the rivers Pinka and Lafnitz were performed from spring 2012 until autumn 2014. In addition meteorological measurements of global shortwave and longwave radiation, air temperature, wind and air humidity were 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. This time period also includes the heat episode of summer 2013 during which the highest air temperature ever recorded in Austria was reported on 8 August at 40.5°C. 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. The influence of riparian vegetation on water temperature, leading to lower water temperature by shading, is also detectable

  10. Marine and Hydrokinetic Renewable Energy Technologies: Potential Navigational Impacts and Mitigation Measures

    SciTech Connect

    Cool, Richard, M.; Hudon, Thomas, J.; Basco, David, R.; Rondorf, Neil, E.

    2009-12-10

    On April 15, 2008, the Department of Energy (DOE) issued a Funding Opportunity Announcement for Advanced Water Power Projects which included a Topic Area for Marine and Hydrokinetic Renewable Energy Market Acceleration Projects. Within this Topic Area, DOE identified potential navigational impacts of marine and hydrokinetic renewable energy technologies and measures to prevent adverse impacts on navigation as a sub-topic area. DOE defines marine and hydrokinetic technologies as those capable of utilizing one or more of the following resource categories for energy generation: ocean waves; tides or ocean currents; free flowing water in rivers or streams; and energy generation from the differentials in ocean temperature. PCCI was awarded Cooperative Agreement DE-FC36-08GO18177 from the DOE to identify the potential navigational impacts and mitigation measures for marine hydrokinetic technologies, as summarized herein. The contract also required cooperation with the U.S. Coast Guard (USCG) and two recipients of awards (Pacific Energy Ventures and reVision) in a sub-topic area to develop a protocol to identify streamlined, best-siting practices. Over the period of this contract, PCCI and our sub-consultants, David Basco, Ph.D., and Neil Rondorf of Science Applications International Corporation, met with USCG headquarters personnel, with U.S. Army Corps of Engineers headquarters and regional personnel, with U.S. Navy regional personnel and other ocean users in order to develop an understanding of existing practices for the identification of navigational impacts that might occur during construction, operation, maintenance, and decommissioning. At these same meetings, “standard” and potential mitigation measures were discussed so that guidance could be prepared for project developers. Concurrently, PCCI reviewed navigation guidance published by the USCG and international community. This report summarizes the results of this effort, provides guidance in the form of a

  11. Measurements of thermophysical properties by a stepwise heating method

    NASA Astrophysics Data System (ADS)

    Araki, N.

    1984-03-01

    An outline of the stepwise heating method for measuring thermal diffusivity and specific heat capacity of samples in both solid and liquid phases is described. The method is based on the measurement of temperature response at the surface of a solid sample when the other surface is heated in step-function. By making the best use of the characteristic points of this method, applications to samples in the liquid state, especially to high temperature melts such as molten salts, have been tried. As examples of measurement results, the thermal diffusivity, specific heat capacity, and thermal conductivity of zirconia brick and the thermal diffusivity of molten salts are shown in graphic form.

  12. A Survey of Measurement, Mitigation, and Verification Field Technologies for Carbon Sequestration Geologic Storage

    NASA Astrophysics Data System (ADS)

    Cohen, K. K.; Klara, S. M.; Srivastava, R. D.

    2004-12-01

    The U.S. Department of Energy's (U.S. DOE's) Carbon Sequestration Program is developing state-of-the-science technologies for measurement, mitigation, and verification (MM&V) in field operations of geologic sequestration. MM&V of geologic carbon sequestration operations will play an integral role in the pre-injection, injection, and post-injection phases of carbon capture and storage projects to reduce anthropogenic greenhouse gas emissions. Effective MM&V is critical to the success of CO2 storage projects and will be used by operators, regulators, and stakeholders to ensure safe and permanent storage of CO2. In the U.S. DOE's Program, Carbon sequestration MM&V has numerous instrumental roles: Measurement of a site's characteristics and capability for sequestration; Monitoring of the site to ensure the storage integrity; Verification that the CO2 is safely stored; and Protection of ecosystems. Other drivers for MM&V technology development include cost-effectiveness, measurement precision, and frequency of measurements required. As sequestration operations are implemented in the future, it is anticipated that measurements over long time periods and at different scales will be required; this will present a significant challenge. MM&V sequestration technologies generally utilize one of the following approaches: below ground measurements; surface/near-surface measurements; aerial and satellite imagery; and modeling/simulations. Advanced subsurface geophysical technologies will play a primary role for MM&V. It is likely that successful MM&V programs will incorporate multiple technologies including but not limited to: reservoir modeling and simulations; geophysical techniques (a wide variety of seismic methods, microgravity, electrical, and electromagnetic techniques); subsurface fluid movement monitoring methods such as injection of tracers, borehole and wellhead pressure sensors, and tiltmeters; surface/near surface methods such as soil gas monitoring and infrared

  13. Upwellings mitigated Plio-Pleistocene heat stress for reef corals on the Florida platform (USA)

    NASA Astrophysics Data System (ADS)

    Brachert, Thomas C.; Reuter, Markus; Krüger, Stefan; Kirkerowicz, Julia; Klaus, James S.

    2016-03-01

    The fast growing calcareous skeletons of zooxanthellate reef corals (z corals) represent unique environmental proxy archives through their oxygen and carbon stable isotope composition (δ18O, δ13C). In addition, the accretion of the skeleton itself is ultimately linked to the environment and responds with variable growth rates (extension rate) and density to environmental changes. Here we present classical proxy data (δ18O, δ13C) in combination with calcification records from 15 massive z corals. The z corals were sampled from four interglacial units of the Florida carbonate platform (USA) dated approximately 3.2, 2.9, 1.8 and 1.2 Ma (middle Pliocene to early Pleistocene). The z corals (Solenastrea, Orbicella, Porites) derive from unlithified shallow marine carbonates and were carefully screened for primary preservation suited for proxy analysis. We show that skeletal accretion responded with decreasing overall calcification rates (decreasing extension rate but increasing density) to warmer water temperatures. Under high annual water temperatures, inferred from sub-annually resolved δ18O data, skeletal bulk density was high, but extension rates and overall calcification rates were at a minimum (endmember scenario 1). Maximum skeletal density was reached during the summer season giving rise to a growth band of high density within the annually banded skeletons ("high density band", HDB). With low mean annual water temperatures (endmember scenario 2), bulk skeletal density was low but extension rates and calcification rates reached a maximum, and under these conditions the HDB formed during winter. Although surface water temperatures in the Western Atlantic warm pool during the interglacials of the late Neogene were ˜ 2 °C higher than they are in the present day, intermittent upwelling of cool, nutrient-rich water mitigated water temperatures off south-western Florida and created temporary refuges for z coral growth. Based on the sub-annually resolved δ18O and

  14. Upwellings mitigated Plio-Pleistocene heat stress for reef corals on the Florida platform (USA)

    NASA Astrophysics Data System (ADS)

    Brachert, T. C.; Reuter, M.; Krüger, S.; Kirkerowicz, J.; Klaus, J. S.

    2015-10-01

    The fast growing calcareous skeletons of zooxanthellate reef corals (z-corals) represent unique environmental proxy archives through their oxygen and carbon stable isotope composition (δ18O, δ13C). In addition, the accretion of the skeleton itself is ultimately linked to the environment and responds with variable growth rates (extension rate) and density to environmental changes. Here we present classical proxy data (δ18O, δ13C) in combination with calcification records from 15 massive z-corals. The z-corals were sampled from four interglacial units of the Florida carbonate platform (USA) dated approximately 3.2, 2.9, 1.8 and 1.2 Ma (middle Pliocene to early Pleistocene). The z-corals (Solenastrea, Orbicella, Porites) derive from unlithified shallow marine carbonates and were carefully screened for primary preservation suited for proxy analysis. We show that skeletal accretion was non-linear and responded with decreasing overall calcification rates (decreasing extension rate but increasing density) to warmer water temperatures. Under high annual water temperatures, inferred from subannually resolved δ18O data, skeletal bulk density was high, but extension rates and overall calcification rates were at a minimum (endmember scenario 1). Maximum skeletal density was reached during the summer season giving rise to a growth band of high density within the annually banded skeletons ("high density band", HDB). With low mean annual water temperatures (endmember scenario 2), bulk skeletal density was low but extension rates and calcification rates reached a maximum, and under these conditions the HDB formed during winter. Although surface water temperatures in the Western Atlantic warm pool during the interglacials of the late Neogene where ∼ 2 °C higher than they are in the present-day, intermittent upwelling of cool, nutrient rich water mitigated water temperatures off southwestern Florida in the middle of the Atlantic warm pool and created temporary refuges for

  15. Targeting Heat Shock Proteins Mitigates Ventilator Induced Diaphragm Muscle Dysfunction in an Age-Dependent Manner

    PubMed Central

    Ogilvie, Hannah; Cacciani, Nicola; Akkad, Hazem; Larsson, Lars

    2016-01-01

    Intensive care unit (ICU) patients are often overtly subjected to mechanical ventilation and immobilization, which leads to impaired limb and respiratory muscle function. The latter, termed ventilator-induced diaphragm dysfunction (VIDD) has recently been related to compromised heat shock protein (Hsp) activation. The administration of a pharmacological drug BGP-15 acting as a Hsp chaperone co-inducer has been found to partially alleviate VIDD in young rats. Considering that the mean age in the ICU is increasing, we aimed to explore whether the beneficial functional effects are also present in old rats. For that, we exposed young (7–8 months) and old (28–32 months) rats to 5-day controlled mechanical ventilation and immobilization with or without systemic BGP-15 administration. We then dissected diaphragm muscles, membrane–permeabilized bundles and evaluated the contractile function at single fiber level. Results confirmed that administration of BGP-15 restored the force-generating capacity of isolated muscle cells from young rats in conjunction with an increased expression of Hsp72. On the other hand, our results highlighted that old rats did not positively respond to the BGP-15 treatment. Therefore, it is of crucial importance to comprehend in more depth the effect of VIDD on diaphragm function and ascertain any further age-related differences. PMID:27729867

  16. Pulse Mitigation and Heat Transfer Enhancement Techniques. Volume 4. Transient Behavior of Heat Pipe With Thermal Energy Storage Under Pulse Heat Loads

    DTIC Science & Technology

    1992-08-01

    the remarkable properties of the heat pipe have become appreciated, and serious developmental work is still taking place. A heat pipe consists of a...transient liquid flow model requires knowledge of the saturation dependence of the capillary flow properties , which can only be determined by experiment...their discretization equations which are physically unrealistic. In light of the above observation, an improved ADI method is proposed. The

  17. Heat flux measurements on ceramics with thin film thermocouples

    NASA Technical Reports Server (NTRS)

    Holanda, Raymond; Anderson, Robert C.; Liebert, Curt H.

    1993-01-01

    Two methods were devised to measure heat flux through a thick ceramic using thin film thermocouples. The thermocouples were deposited on the front and back face of a flat ceramic substrate. The heat flux was applied to the front surface of the ceramic using an arc lamp Heat Flux Calibration Facility. Silicon nitride and mullite ceramics were used; two thicknesses of each material was tested, with ceramic temperatures to 1500 C. Heat flux ranged from 0.05-2.5 MW/m2(sup 2). One method for heat flux determination used an approximation technique to calculate instantaneous values of heat flux vs time; the other method used an extrapolation technique to determine the steady state heat flux from a record of transient data. Neither method measures heat flux in real time but the techniques may easily be adapted for quasi-real time measurement. In cases where a significant portion of the transient heat flux data is available, the calculated transient heat flux is seen to approach the extrapolated steady state heat flux value as expected.

  18. Modeling nexus of urban heat island mitigation strategies with electricity/power usage and consumer costs: a case study for Phoenix, Arizona, USA

    NASA Astrophysics Data System (ADS)

    Silva, Humberto; Fillpot, Baron S.

    2016-11-01

    A reduction in both power and electricity usage was determined using a previously validated zero-dimensional energy balance model that implements mitigation strategies used to reduce the urban heat island (UHI) effect. The established model has been applied to show the change in urban characteristic temperature when executing four common mitigation strategies: increasing the overall (1) emissivity, (2) vegetated area, (3) thermal conductivity, and (4) albedo of the urban environment in a series of increases by 5, 10, 15, and 20% from baseline values. Separately, a correlation analysis was performed involving meteorological data and total daily energy (TDE) consumption where the 24-h average temperature was shown to have the greatest correlation to electricity service data in the Phoenix, Arizona, USA, metropolitan region. A methodology was then developed for using the model to predict TDE consumption reduction and corresponding cost-saving analysis when implementing the four mitigation strategies. The four modeled UHI mitigation strategies, taken in combination, would lead to the largest percent reduction in annual energy usage, where increasing the thermal conductivity is the single most effective mitigation strategy. The single least effective mitigation strategy, increasing the emissivity by 5% from the baseline value, resulted in an average calculated reduction of about 1570 GWh in yearly energy usage with a corresponding 157 million dollar cost savings. When the four parameters were increased in unison by 20% from baseline values, an average calculated reduction of about 2050 GWh in yearly energy usage was predicted with a corresponding 205 million dollar cost savings.

  19. Pulse Mitigation and Heat Transfer Enhancement Techniques. Volume 1. Spray Cooling.

    DTIC Science & Technology

    1992-08-01

    Temperature 32 S 4.4 Contact Angle Measurements 33 4.5 Contact Angle Effects 35 4.6 Surface Roughness Measurements 36 4.7 Surface Roughness Effects 37...Effect of Coolant Temperature - 3 71 4.9 Contact Angles 72 V 0 0 0 0 0 0 0 0 0 0 4.10 Effect of S--face Contact Angle - 1 73 4.11 Effect of Surface... Contact Angle - 2 74 4.12 Effect of Surface Contact Angle 3 75 4.13 Roughness Profile - 14-pm-grit polish 76 4.14 Roughness Profile - 0.3-pm-grit polish 77

  20. Using a Cold Radiometer to Measure Heat Loads and Survey Heat Leaks

    NASA Technical Reports Server (NTRS)

    DiPirro, M.; Tuttle, J.; Hait, T.; Shirron, P.

    2013-01-01

    We have developed an inexpensive cold radiometer for use in thermal/vacuum chambers to measure heat loads, characterize emissivity and specularity of surfaces and to survey areas to evaluate stray heat loads. We report here the results of two such tests for the James Webb Space Telescope to measure heat loads and effective emissivities of2 major pieces of optical ground support equipment that will be used in upcoming thermal vacuum testing of the Telescope.

  1. Using a Cold Radiometer to Measure Heat Loads and Survey Heat Leaks

    NASA Technical Reports Server (NTRS)

    Dipirro, M.; Tuttle, J.; Hait, T.; Shirron, P.

    2014-01-01

    We have developed an inexpensive cold radiometer for use in thermal/vacuum chambers to measure heat loads, characterize emissivity and specularity of surfaces and to survey areas to evaluate stray heat loads. We report here the results of two such tests for the James Webb Space Telescope to measure heat loads and effective emissivities of 2 major pieces of optical ground support equipment that will be used in upcoming thermal vacuum testing of the Telescope.

  2. Heat flux measurement in SSME turbine blade tester

    NASA Astrophysics Data System (ADS)

    Liebert, Curt H.

    1990-11-01

    Surface heat flux values were measured in the turbine blade thermal cycling tester located at NASA-Marshall. This is the first time heat flux has been measured in a space shuttle main engine turbopump environment. Plots of transient and quasi-steady state heat flux data over a range of about 0 to 15 MW/sq m are presented. Data were obtained with a miniature heat flux gage device developed at NASA-Lewis. The results from these tests are being incorporated into turbine design models. Also, these gages are being considered for airfoil surface heat flux measurement on turbine vanes mounted in SSME turbopump test bed engine nozzles at Marshall. Heat flux effects that might be observed on degraded vanes are discussed.

  3. Heat flux measurement in SSME turbine blade tester

    NASA Astrophysics Data System (ADS)

    Liebert, Curt H.

    Surface heat flux values were measured in the turbine blade thermal cycling tester located at NASA-Marshall. This is the first time heat flux has been measured in a space shuttle main engine turbopump environment. Plots of transient and quasi-steady state heat flux data over a range of about 0 to 15 MW/sq m are presented. Data were obtained with a miniature heat flux gage device developed at NASA-Lewis. The results from these tests are being incorporated into turbine design models. Also, these gages are being considered for airfoil surface heat flux measurement on turbine vanes mounted in SSME turbopump test bed engine nozzles at Marshall. Heat flux effects that might be observed on degraded vanes are discussed.

  4. Heat flux measurement in SSME turbine blade tester

    NASA Technical Reports Server (NTRS)

    Liebert, Curt H.

    1990-01-01

    Surface heat flux values were measured in the turbine blade thermal cycling tester located at NASA-Marshall. This is the first time heat flux has been measured in a space shuttle main engine turbopump environment. Plots of transient and quasi-steady state heat flux data over a range of about 0 to 15 MW/sq m are presented. Data were obtained with a miniature heat flux gage device developed at NASA-Lewis. The results from these tests are being incorporated into turbine design models. Also, these gages are being considered for airfoil surface heat flux measurement on turbine vanes mounted in SSME turbopump test bed engine nozzles at Marshall. Heat flux effects that might be observed on degraded vanes are discussed.

  5. Mitigation of the impact of terrestrial contamination on organic measurements from the Mars Science Laboratory.

    PubMed

    ten Kate, Inge L; Canham, John S; Conrad, Pamela G; Errigo, Therese; Katz, Ira; Mahaffy, Paul R

    2008-06-01

    The objective of the 2009 Mars Science Laboratory (MSL), which is planned to follow the Mars Exploration Rovers and the Phoenix lander to the surface of Mars, is to explore and assess quantitatively a site on Mars as a potential habitat for present or past life. Specific goals include an assessment of the past or present biological potential of the target environment and a characterization of its geology and geochemistry. Included in the 10 investigations of the MSL rover is the Sample Analysis at Mars (SAM) instrument suite, which is designed to obtain trace organic measurements, measure water and other volatiles, and measure several light isotopes with experiment sequences designed for both atmospheric and solid-phase samples. SAM integrates a gas chromatograph, a mass spectrometer, and a tunable laser spectrometer supported by sample manipulation tools both within and external to the suite. The sub-part-per-billion sensitivity of the suite for trace species, particularly organic molecules, along with a mobile platform that will contain many kilograms of organic materials, presents a considerable challenge due to the potential for terrestrial contamination to mask the signal of martian organics. We describe the effort presently underway to understand and mitigate, wherever possible within the resource constraints of the mission, terrestrial contamination in MSL and SAM measurements.

  6. Measurement requirements for a Near-Earth Asteroid impact mitigation demonstration mission

    NASA Astrophysics Data System (ADS)

    Wolters, Stephen D.; Ball, Andrew J.; Wells, Nigel; Saunders, Christopher; McBride, Neil

    2011-10-01

    A concept for an Impact Mitigation Preparation Mission, called Don Quijote, is to send two spacecrafts to a Near-Earth Asteroid (NEA): an Orbiter and an Impactor. The Impactor collides with the asteroid while the Orbiter measures the resulting change in the asteroid's orbit, by means of a Radio Science Experiment (RSE) carried out before and after the impact. Three parallel Phase A studies on Don Quijote were carried out for the European Space Agency: the research presented here reflects the outcomes of the study by QinetiQ. We discuss the mission objectives with regard to the prioritisation of payload instruments, with emphasis on the interpretation of the impact. The Radio Science Experiment is described and it is examined how solar radiation pressure may increase the uncertainty in measuring the orbit of the target asteroid. It is determined that to measure the change in orbit accurately a thermal IR spectrometer is mandatory, to measure the Yarkovsky effect. The advantages of having a laser altimeter are discussed. The advantages of a dedicated wide-angle impact camera are discussed and the field-of-view is initially sized through a simple model of the impact.

  7. Device for Measuring Heat Capacities of Microcalorimeter Absorber Materials

    NASA Astrophysics Data System (ADS)

    Kotsubo, Vincent; Beall, James; Ullom, Joel

    2009-12-01

    We are developing a device for measuring the heat capacity of candidate absorber materials for gamma-ray microcalorimeters with the goal of finding materials with low heat capacity and high stopping power to improve detector efficiency. To date, only Sn has been effective as an absorber, and speculation is that other materials suffer from anomalously high heat capacities at low temperatures. The key component of the measurement device is a 17 mm×17 mm low heat capacity silicon platform suspended by Kevlar fibers designed for accepting 1 g to 2 g samples, and whose heat capacity can be characterized prior to attaching a sample. The platform has a thin film Pd/Au heater deposited directly on the silicon, and a semiconducting thermometer bonded to the surface. The heat capacity is determined from C = Gτ, where G is the in-situ measured conductance and x is the measured temperature decay time from a step change in applied heat. For a platform without samples, decay periods on the order of 0.3 to 0.05 seconds were measured. With samples, decay periods of several seconds are projected, allowing good resolution of the heat capacities. Several thermometers were tested in an effort to find one with the optimum characteristics for measuring platform temperatures. These included a commercial thick-film Ruthenium-oxide surface-mount resistor, a germanium NTD, and a zirconium oxy-nitride thin-film thermometer.

  8. Nanomanufacturing concerns about measurements made in the SEM part IV: charging and its mitigation

    NASA Astrophysics Data System (ADS)

    Postek, Michael T.; Vladár, András. E.

    2015-08-01

    This is the fourth part of a series of tutorial papers discussing various causes of measurement uncertainty in scanned particle beam instruments, and some of the solutions researched and developed at NIST and other research institutions. Scanned particle beam instruments especially the scanning electron microscope (SEM) have gone through tremendous evolution to become indispensable tools for many and diverse scientifi c and industrial applications. These improvements have signifi cantly enhanced their performance and made them far easier to operate. But, the ease of operation has also fostered operator complacency. In addition, the user-friendliness has reduced the apparent need for extensive operator training. Unfortunately, this has led to the idea that the SEM is just another expensive "digital camera" or another peripheral device connected to a computer and that all of the problems in obtaining good quality images and data have been solved. Hence, one using these instruments may be lulled into thinking that all of the potential pitfalls have been fully eliminated and believing that, everything one sees on the micrograph is always correct. But, as described in this and the earlier papers, this may not be the case. Care must always be taken when reliable quantitative data are being sought. The fi rst paper in this series discussed some of the issues related to signal generation in the SEM, including instrument calibration, electron beam-sample interactions and the need for physics-based modeling to understand the actual image formation mechanisms to properly interpret SEM images. The second paper has discussed another major issue confronting the microscopist: specimen contamination and methods to eliminate it. The third paper discussed mechanical vibration and stage drift and some useful solutions to mitigate the problems caused by them, and here, in this the fourth contribution, the issues related to specimen "charging" and its mitigation are discussed relative

  9. Atmospheric particulate mercury in the megacity Beijing: Efficiency of mitigation measures and assessment of health effects

    NASA Astrophysics Data System (ADS)

    Schleicher, N. J.; Schäfer, J.; Chen, Y.; Blanc, G.; Chen, Y.; Chai, F.; Cen, K.; Norra, S.

    2016-01-01

    Atmospheric particulate mercury (HgP) was studied before, during, and after the Olympic Summer Games in Beijing, China, in August 2008 in order to investigate the efficiency of the emission control measures implemented by the Chinese Government. These source control measures comprised traffic reductions, increase in public transportation, planting of vegetation, establishment of parks, building freeze at construction sites, cleaner production techniques for industries and industry closures in Beijing and also in the surrounding areas. Strictest measures including the "odd-even ban" to halve the vehicle volume were enforced from the 20th of July to the 20th of September 2008. The Olympic period provided the unique opportunity to investigate the efficiency of these comprehensive actions implemented in order to reduce air pollution on a large scale. Therefore, the sampling period covered summer (August, September) and winter (December and January) samples over several years from December 2005 to September 2013. Average HgP concentrations in total suspended particulates (TSP) sampled in August 2008 were 81 ± 39 pg/m3 while TSP mass concentrations were 93 ± 49 μg/m3. This equals a reduction by about 63% for TSP mass and 65% for HgP, respectively, compared to the previous two years demonstrating the short-term success of the measures. However, after the Olympic Games, HgP concentrations increased again to pre-Olympic levels in August 2009 while values in August 2010 decreased again by 30%. Moreover, winter samples, which were 2- to 11-fold higher than corresponding August values, showed decreasing concentrations over the years indicating a long-term improvement of HgP pollution in Beijing. However, regarding adverse health effects, comparisons with soil guideline values and studies from other cities highlighted that HgP concentrations in TSP remained high in Beijing despite respective control measures. Consequently, future mitigation measures need to be tailored more

  10. Evaluation of mitigation measures to reduce hydropeaking impacts on river ecosystems - a case study from the Swiss Alps.

    PubMed

    Tonolla, Diego; Bruder, Andreas; Schweizer, Steffen

    2017-01-01

    New Swiss legislation obligates hydropower plant owners to reduce detrimental impacts on rivers ecosystems caused by hydropeaking. We used a case study in the Swiss Alps (hydropower company Kraftwerke Oberhasli AG) to develop an efficient and successful procedure for the ecological evaluation of such impacts, and to predict the effects of possible mitigation measures. We evaluated the following scenarios using 12 biotic and abiotic indicators: the pre-mitigation scenario (i.e. current state), the future scenario with increased turbine capacity but without mitigation measures, and future scenarios with increased turbine capacity and four alternative mitigation measures. The evaluation was based on representative hydrographs and quantitative or qualitative prediction of the indicators. Despite uncertainties in the ecological responses and the future operation mode of the hydropower plant, the procedure allowed the most appropriate mitigation measure to be identified. This measure combines a basin and a cavern at a total retention volume of 80,000m(3), allowing for substantial dampening in the flow falling and ramping rates and in turn considerable reduction in stranding risk for juvenile trout and in macroinvertebrate drift. In general, this retention volume had the greatest predicted ecological benefit and can also, to some extent, compensate for possible modifications in the hydropower operation regime in the future, e.g. due to climate change, changes in the energy market, and changes in river morphology. Furthermore, it also allows for more specific seasonal regulations of retention volume during ecologically sensitive periods (e.g. fish spawning seasons). Overall experience gained from our case study is expected to support other hydropeaking mitigation projects.

  11. Debris mitigation measures by satellite design and operational methods - Findings from the DLR space debris End-to-End Service

    NASA Astrophysics Data System (ADS)

    Sdunnus, H.; Beltrami, P.; Janovsky, R.; Koppenwallner, G.; Krag, H.; Reimerdes, H.; Schäfer, F.

    Debris Mitigation has been recognised as an issue to be addressed by the space faring nations around the world. Currently, there are various activities going on, aiming at the establishment of debris mitigation guidelines on various levels, reaching from the UN down to national space agencies. Though guidelines established on the national level already provide concrete information how things should be done (rather that specifying what should be done or providing fundamental principles) potential users of the guidelines will still have the need to explore the technical, management, and financial implications of the guidelines for their projects. Those questions are addressed by the so called "Space Debris End-to-End Service" project, which has been initiated as a national initiative of the German Aerospace Centre (DLR). Based on a review of already existing mitigation guidelines or guidelines under development and following an identification of needs from a circle of industrial users the "End-to-End Service Gu idelines" have been established for designer and operators of spacecraft. The End-to-End Service Guidelines are based on requirements addressed by the mitigation guidelines and provide recommendations how and when the technical consideration of the mitigation guidelines should take place. By referencing requirements from the mitigation guidelines, the End-to-End Service Guidelines address the consideration of debris mitigation measures by spacecraft design and operational measures. This paper will give an introduction to the End-to-End Service Guidelines. It will focus on the proposals made for mitigation measures by the S/C system design, i.e. on protective design measures inside the spacecraft and on design measures, e.g. innovative protective (shielding) systems. Furthermore, approaches on the analytical optimisation of protective systems will be presented, aiming at the minimisation of shield mass under conservation of the protective effects. On the

  12. An optimization model for regional air pollutants mitigation based on the economic structure adjustment and multiple measures: A case study in Urumqi city, China.

    PubMed

    Sun, Xiaowei; Li, Wei; Xie, Yulei; Huang, Guohe; Dong, Changjuan; Yin, Jianguang

    2016-11-01

    A model based on economic structure adjustment and pollutants mitigation was proposed and applied in Urumqi. Best-worst case analysis and scenarios analysis were performed in the model to guarantee the parameters accuracy, and to analyze the effect of changes of emission reduction styles. Results indicated that pollutant-mitigations of electric power industry, iron and steel industry, and traffic relied mainly on technological transformation measures, engineering transformation measures and structure emission reduction measures, respectively; Pollutant-mitigations of cement industry relied mainly on structure emission reduction measures and technological transformation measures; Pollutant-mitigations of thermal industry relied mainly on the four mitigation measures. They also indicated that structure emission reduction was a better measure for pollutants mitigation of Urumqi. Iron and steel industry contributed greatly in SO2, NOx and PM (particulate matters) emission reduction and should be given special attention in pollutants emission reduction. In addition, the scales of iron and steel industry should be reduced with the decrease of SO2 mitigation amounts. The scales of traffic and electric power industry should be reduced with the decrease of NOx mitigation amounts, and the scales of cement industry and iron and steel industry should be reduced with the decrease of PM mitigation amounts. The study can provide references of pollutants mitigation schemes to decision-makers for regional economic and environmental development in the 12th Five-Year Plan on National Economic and Social Development of Urumqi.

  13. Heat Island Compendium

    EPA Pesticide Factsheets

    Heat islands can be mitigated through measures like planting trees and vegetation, installing green roofs and cool roofs, and using cool pavements. The compendium describes all of these strategies and shows how communities around the country are being used

  14. Heat flux measurement in a high enthalpy plasma flow

    NASA Astrophysics Data System (ADS)

    Löhle, Stefan; Battaglia, Jean-Luc; Gardarein, Jean-Laurent; Jullien, Pierre; van Ootegem, Bruno

    2008-11-01

    It is a widely used approach to measure heat flux in harsh environments like high enthalpy plasma flows, fusion plasma and rocket motor combustion chambers based on solving the inverse heat conduction problem in a semi-infinite environment. This approach strongly depends on model parameters and geometrical aspects of the sensor design. In this work the surface heat flux is determined by solving the inverse heat conduction problem using an identified system as a direct model. The identification of the system is performed using calibration measurements with modern laser technique and advanced data handling. The results of the identified thermo-physical system show that a non-integer model appears most adapted to this particular problem. It is concluded that the new method improves the heat flux sensor significantly and furthermore extend its application to very short measurement times.

  15. A laser-induced heat flux technique for convective heat transfer measurements in high speed flows

    NASA Technical Reports Server (NTRS)

    Porro, A. R.; Keith, T. G., Jr.; Hingst, W. R.

    1991-01-01

    A technique is developed to measure the local convective heat transfer coefficient on a model surface in a supersonic flow field. The technique uses a laser to apply a discrete local heat flux at the model test surface, and an infrared camera system determines the local temperature distribution due to the heating. From this temperature distribution and an analysis of the heating process, a local convective heat transfer coefficient is determined. The technique was used to measure the local surface convective heat transfer coefficient distribution on a flat plate at nominal Mach numbers of 2.5, 3.0, 3.5, and 4.0. The flat plate boundary layer initially was laminar and became transitional in the measurement region. The experimentally determined convective heat transfer coefficients were generally higher than the theoretical predictions for flat plate laminar boundary layers. However, the results indicate that this nonintrusive optical measurement technique has the potential to measure surface convective heat transfer coefficients in high-speed flowfields.

  16. A laser-induced heat flux technique for convective heat transfer measurements in high speed flows

    NASA Technical Reports Server (NTRS)

    Porro, A. R.; Keith, T. G., Jr.; Hingst, W. R.

    1991-01-01

    A technique is developed to measure the local convective heat transfer coefficient on a model surface in a supersonic flow field. The technique uses a laser to apply a discrete local heat flux at the model test surface, and an infrared camera system determines the local temperature distribution due to the heating. From this temperature distribution and an analysis of the heating process, a local convective heat transfer coefficient is determined. The technique was used to measure the local surface convective heat transfer coefficient distribution on a flat plate at nominal Mach numbers of 2.5, 3.0, 3.5, and 4.0. The flat plate boundary layer initially was laminar and became transitional in the measurement region. The experimentally determined convective heat transfer coefficients were generally higher than the theoretical predictions for flat plate laminar boundary layers. However, the results indicate that this nonintrusive optical measurement technique has the potential to measure surface convective heat transfer coefficients in high speed flow fields.

  17. Heat Transfer Salts for Nuclear Reactor Systems - Chemistry Control, Corrosion Mitigation, and Modeling

    SciTech Connect

    Anderson, Mark; Sridharan, Kumar; Morgan, Dane; Peterson, Per; Calderoni, Pattrick; Scheele, Randall; Casekka, Andrew; McNamara, Bruce

    2015-01-22

    The concept of a molten salt reactor has existed for nearly sixty years. Previously all work was done during a large collaborative effort at Oak Ridge National Laboratory, culminating in a research reactor which operated for 15,000 hours without major error. This technical success has garnished interest in modern, high temperature, reactor schemes. Research using molten fluoride salts for nuclear applications requires a steady supply of high grade molten salts. There is no bulk supplier of research grade fluoride salts in the world, so a facility which could provide all the salt needed for testing at the University of Wisconsin had to be produced. Two salt purification devices were made for this purpose, a large scale purifier, and a small scale purifier, each designed to clean the salts from impurities and reduce their corrosion potential. As of now, the small scale has performed with flibe salt, hydrogen, and hydrogen fluoride, yielding clean salt. This salt is currently being used in corrosion testing facilities at the Massachusetts Institute of Technology and the University of Wisconsin. Working with the beryllium based salts requires extensive safety measures and health monitoring to prevent the development of acute or chronic beryllium disease, two pulmonary diseases created by an allergic reaction to beryllium in the lungs. Extensive health monitoring, engineering controls, and environment monitoring had to be set up with the University of Wisconsin department of Environment, Health and Safety. The hydrogen fluoride required for purification was also an extreme health hazard requiring thoughtful planning and execution. These dangers have made research a slow and tedious process. Simple processes, such as chemical handling and clean-up, can take large amounts of ingenuity and time. Other work has complemented the experimental research at Wisconsin to advance high temperature reactor goals. Modeling work has been performed in house to re

  18. Long term performance of radon mitigation systems

    SciTech Connect

    Prill, R.; Fisk, W.J.

    2002-03-01

    Researchers installed radon mitigation systems in 12 houses in Spokane, Washington and Coeur d'Alene, Idaho during the heating season 1985--1986 and continued to monitor indoor radon quarterly and annually for ten years. The mitigation systems included active sub-slab ventilation, basement over-pressurization, and crawlspace isolation and ventilation. The occupants reported various operational problems with these early mitigation systems. The long-term radon measurements were essential to track the effectiveness of the mitigation systems over time. All 12 homes were visited during the second year of the study, while a second set 5 homes was visited during the fifth year to determine the cause(s) of increased radon in the homes. During these visits, the mitigation systems were inspected and measurements of system performance were made. Maintenance and modifications were performed to improve system performance in these homes.

  19. Planetary heat flow from shallow subsurface measurements: Mars

    NASA Astrophysics Data System (ADS)

    Cornwall, Marc; Hagermann, Axel

    2016-10-01

    Planetary heat flow probes measure heat flow (depth-resolved temperature and thermal conductivity) to provide insight into the internal state of a planet. The probes have been utilized extensively on Earth, twice on the Moon, and once on the Surface of comet 67P-CG. Mars is an important target for heat flow measurement as heat flow is a critical parameter in Martian thermal history models. Earlier studies indicate that Martian planetary heat flow can be accessed at 5 m below the surface in dry regolith monitored over at least one Martian year. A one Martian year monitoring period is necessary because, in the shallow subsurface, heat flow from the interior is superposed with time varying heat flow contributions, primarily due to insolation. Given that a heat flow probe may not achieve its target depth or monitoring period, this study investigates how the depth (2-5 m), duration (0-1 Martian year) and quality of measurements influence the accuracy of planetary heat flow. An inverse model is used to show that, in the preceding scenarios, the accuracy of planetary heat flow directly estimated from depth-dependent thermal conductivity with 10-20% precision errors, temperatures with 50-100 mK precision errors and modelling uncertainties up to 500 mK, can, on average, be improved by a factor of 27 with optimization to 13%. Accuracies increase with sensor penetration depth and regolith monitoring period. Heat flow optimized from instantaneous measurements or those with the shortest regolith monitoring periods have increased accuracy where the frequency and amplitude of the temperature variation are lowest. The inverse model is based on the Function Specification Inversion method. This study demonstrates that a solution subspace can be identified within a space of uncertainties modelled for the temperature measurements and planetary heat flow: the subspace is defined by a constant log-ratio of their respective standard deviations. Optimized heat flow estimates display

  20. UNDERSTANDING METHANE EMISSIONS SOURCES AND VIABLE MITIGATION MEASURES IN THE NATURAL GAS TRANSMISSION SYSTEMS: RUSSIAN AND U.S. EXPERIENCE

    SciTech Connect

    Ishkov, A.; Akopova, Gretta; Evans, Meredydd; Yulkin, Grigory; Roshchanka, Volha; Waltzer, Suzie; Romanov, K.; Picard, David; Stepanenko, O.; Neretin, D.

    2011-10-01

    This article will compare the natural gas transmission systems in the U.S. and Russia and review experience with methane mitigation technologies in the two countries. Russia and the United States (U.S.) are the world's largest consumers and producers of natural gas, and consequently, have some of the largest natural gas infrastructure. This paper compares the natural gas transmission systems in Russia and the U.S., their methane emissions and experiences in implementing methane mitigation technologies. Given the scale of the two systems, many international oil and natural gas companies have expressed interest in better understanding the methane emission volumes and trends as well as the methane mitigation options. This paper compares the two transmission systems and documents experiences in Russia and the U.S. in implementing technologies and programs for methane mitigation. The systems are inherently different. For instance, while the U.S. natural gas transmission system is represented by many companies, which operate pipelines with various characteristics, in Russia predominately one company, Gazprom, operates the gas transmission system. However, companies in both countries found that reducing methane emissions can be feasible and profitable. Examples of technologies in use include replacing wet seals with dry seals, implementing Directed Inspection and Maintenance (DI&M) programs, performing pipeline pump-down, applying composite wrap for non-leaking pipeline defects and installing low-bleed pneumatics. The research methodology for this paper involved a review of information on methane emissions trends and mitigation measures, analytical and statistical data collection; accumulation and analysis of operational data on compressor seals and other emission sources; and analysis of technologies used in both countries to mitigate methane emissions in the transmission sector. Operators of natural gas transmission systems have many options to reduce natural gas losses

  1. Voluntary suppression of hyperthermia-induced hyperventilation mitigates the reduction in cerebral blood flow velocity during exercise in the heat.

    PubMed

    Tsuji, Bun; Honda, Yasushi; Ikebe, Yusuke; Fujii, Naoto; Kondo, Narihiko; Nishiyasu, Takeshi

    2015-04-15

    Hyperthermia during prolonged exercise leads to hyperventilation, which can reduce arterial CO2 pressure (PaCO2 ) and, in turn, cerebral blood flow (CBF) and thermoregulatory response. We investigated 1) whether humans can voluntarily suppress hyperthermic hyperventilation during prolonged exercise and 2) the effects of voluntary breathing control on PaCO2 , CBF, sweating, and skin blood flow. Twelve male subjects performed two exercise trials at 50% of peak oxygen uptake in the heat (37°C, 50% relative humidity) for up to 60 min. Throughout the exercise, subjects breathed normally (normal-breathing trial) or they tried to control their minute ventilation (respiratory frequency was timed with a metronome, and target tidal volumes were displayed on a monitor) to the level reached after 5 min of exercise (controlled-breathing trial). Plotting ventilatory and cerebrovascular responses against esophageal temperature (Tes) showed that minute ventilation increased linearly with rising Tes during normal breathing, whereas controlled breathing attenuated the increased ventilation (increase in minute ventilation from the onset of controlled breathing: 7.4 vs. 1.6 l/min at +1.1°C Tes; P < 0.001). Normal breathing led to decreases in estimated PaCO2 and middle cerebral artery blood flow velocity (MCAV) with rising Tes, but controlled breathing attenuated those reductions (estimated PaCO2 -3.4 vs. -0.8 mmHg; MCAV -10.4 vs. -3.9 cm/s at +1.1°C Tes; P = 0.002 and 0.011, respectively). Controlled breathing had no significant effect on chest sweating or forearm vascular conductance (P = 0.67 and 0.91, respectively). Our results indicate that humans can voluntarily suppress hyperthermic hyperventilation during prolonged exercise, and this suppression mitigates changes in PaCO2 and CBF.

  2. Mitigation measures to reduce losses of phosphorus during the non-cropping period - a northern European perspective

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Degradation of natural waters by phosphorus (P) due to agricultural activities has been a problem in several countries for many years. Accordingly, mitigation measures to minimize this issue have been developed and used with varying success. Non-point source P from agricultural fields is one of the ...

  3. 40 CFR 93.125 - Enforceability of design concept and scope and project-level mitigation and control measures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Enforceability of design concept and... Transit Laws § 93.125 Enforceability of design concept and scope and project-level mitigation and control... measures which are identified as conditions for NEPA process completion with respect to local CO, PM10,...

  4. 40 CFR 93.125 - Enforceability of design concept and scope and project-level mitigation and control measures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Enforceability of design concept and... Transit Laws § 93.125 Enforceability of design concept and scope and project-level mitigation and control... measures which are identified as conditions for NEPA process completion with respect to local CO, PM10,...

  5. 40 CFR 93.125 - Enforceability of design concept and scope and project-level mitigation and control measures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Enforceability of design concept and... Transit Laws § 93.125 Enforceability of design concept and scope and project-level mitigation and control... measures which are identified as conditions for NEPA process completion with respect to local CO, PM10,...

  6. 40 CFR 93.125 - Enforceability of design concept and scope and project-level mitigation and control measures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Enforceability of design concept and... Transit Laws § 93.125 Enforceability of design concept and scope and project-level mitigation and control... measures which are identified as conditions for NEPA process completion with respect to local CO, PM10,...

  7. Agricultural non-point source pollution in China: causes and mitigation measures.

    PubMed

    Sun, Bo; Zhang, Linxiu; Yang, Linzhang; Zhang, Fusuo; Norse, David; Zhu, Zhaoliang

    2012-06-01

    Non-point source (NPS) pollution has been increasingly serious in China since the 1990s. The increases of agricultural NPS pollution in China is evaluated for the period 2000-2008 by surveying the literature on water and soil pollution from fertilizers and pesticides, and assessing the surplus nitrogen balance within provinces. The main causes for NPS pollution were excessive inputs of nitrogen fertilizer and pesticides, which were partly the result of the inadequate agricultural extension services and the rapid expansion of intensive livestock production with little of waste management. The annual application of synthetic nitrogen fertilizers and pesticides in China increased by 50.7 and 119.7%, respectively, during 1991-2008. The mitigation measures to reduce NPS pollution include: correct distortion in fertilizer prices; improve incentives for the recycling of organic manure; provide farmers with better information on the sound use of agro-chemicals; and tighten the regulations and national standards on organic waste disposal and pesticides use.

  8. Method of measuring heat influx of a cryogenic transfer system

    DOEpatents

    Niemann, Ralph C.; Zelipsky, Steven A.; Rezmer, Ronald R.; Smelser, Peter

    1981-01-01

    A method is provided for measuring the heat influx of a cryogenic transfer system. A gaseous phase of the cryogen used during normal operation of the system is passed through the system. The gaseous cryogen at the inlet to the system is tempered to duplicate the normal operating temperature of the system inlet. The temperature and mass flow rate of the gaseous cryogen is measured at the outlet of the system, and the heat capacity of the cryogen is determined. The heat influx of the system is then determined from known thermodynamic relationships.

  9. Risk mitigation measures for diffuse pesticide entry into aquatic ecosystems: proposal of a guide to identify appropriate measures on a catchment scale.

    PubMed

    Bereswill, Renja; Streloke, Martin; Schulz, Ralf

    2014-04-01

    Measures to mitigate the risk of pesticide entry into aquatic ecosystems are becoming increasingly more important in the management of hot spots of pesticide transfer; such management, for example, is required by the European Union's directive for the sustainable use of pesticides (2009/128/EC). Measures beyond those currently stipulated for pesticide product authorization may be needed. A concise compilation of the appropriate measures for users (that are primarily farmers but also, e.g., regulators and farm extension services) and a guide for practically identifying these measures at the catchment scale is currently not available. Therefore, a proposal was developed for a guide focusing on the most important diffuse entry pathways (spray drift and runoff). Based on a survey of exposure-relevant landscape parameters (i.e., the riparian buffer strip width, riparian vegetation type, density of ground vegetation cover, coverage of the water body with aquatic macrophytes, field slope, and existence of concentrated flow paths), a set of risk mitigation measures focusing on the specific situation of pollution of a water body catchment can be identified. The user can then choose risk mitigation measures to implement, assisted by evaluations of their efficiency in reducing pesticide entry, feasibility, and expected acceptability to farmers. Currently, 12 landscape-related measures and 6 application-related measures are included. The present guide presents a step toward the practical implementation of risk mitigation measures for reducing pesticide entry in aquatic ecosystems.

  10. Modelling of agricultural diffuse pollution and mitigation measures effectiveness in Wallonia (Belgium)

    NASA Astrophysics Data System (ADS)

    Sohier, C.; Deraedt, D.; Degré, A.

    2012-04-01

    Implementation of European directives in the environmental field and, specially, in the water management field, generates a request from policy-makers for news tools able to evaluate impact of management measures aiming at reducing pressures on ecosystems. In Wallonia (Southern Region of Belgium), the Nitrate Directive (EEC/676/91) was transposed into the "Walloon action plan for nitrogen sustainable management in agriculture" (PGDA1) in 2002. In 2007, a second plan was launched to reinforce some topics (PGDA2). Furthermore, the goal of "good quality" of surface waters and groundwater imposed by the Water Framework Directive poses new challenges in water management. In this context, a "soil and vadose" hydrological model is used in order to evaluate diffuse pollutions and efficiency of mitigation measures. This model, called EPICgrid, has been developed at catchment scale with an original modular concept on the basis of the field scale "water-soil-plant" EPIC model (Williams J.R., Jones C.A., Dyke P.T. (1984). A modelling approach to determining the relationship between erosion and soil productivity. Transactions of the ASAE. 27, 129-144). The model estimates, for each HRU identified into a 1km2 grid, water and nutrients flows into the plant-soil-vadose zone system (Sohier C., Degré A., Dautrebande S. (2009). From root zone modelling to regional forecasting of nitrate concentration in recharge flows - The case of the Walloon Region (Belgium). Journal of Hydrology, Volume 369, Issues 3-4, 15 May 2009, Pages 350-359). The model is used to make prospective simulations in order to evaluate the impact of measures currently performed to reduce the effect of diffuse pollution on water surface quality and groundwater quality, at regional scale. Response of the soil-vadose zone to agricultural practices modification is analyzed for the deadlines of the Water Framework Directive: 2015, 2021 and 2027, taking into account two climatic scenarios. Simulations results showed

  11. Heat flux measurements for use in physiological and clothing research.

    PubMed

    Niedermann, R; Psikuta, A; Rossi, R M

    2014-08-01

    Scientists use passive heat flow meters to measure body heat exchanges with the environment. In recent years, several such sensors have been developed and concerns about their proper calibration have been addressed. However, calibration methods have differed in the geometry of the heated device as well as in the heat transfer mechanism. Therefore, a comparison of calibration methods is needed in order to understand the obtained differences in calibration lines. We chose three commercially available heat flux sensors and placed them on four different heated devices: a hot plate, double hot plate, nude cylinder and a cylinder covered with a spacer material. We found differences between the calibration line of the manufacturer and our own measurements, especially when forced convection was involved as the main heat transfer mechanism. The results showed clearly that the calibration method should be chosen according to the intended purpose of use. In addition, we recommend use a thin, light heat flux sensor with good thermal conduction in human subject studies.

  12. Heat flux measurements for use in physiological and clothing research

    NASA Astrophysics Data System (ADS)

    Niedermann, R.; Psikuta, A.; Rossi, R. M.

    2014-08-01

    Scientists use passive heat flow meters to measure body heat exchanges with the environment. In recent years, several such sensors have been developed and concerns about their proper calibration have been addressed. However, calibration methods have differed in the geometry of the heated device as well as in the heat transfer mechanism. Therefore, a comparison of calibration methods is needed in order to understand the obtained differences in calibration lines. We chose three commercially available heat flux sensors and placed them on four different heated devices: a hot plate, double hot plate, nude cylinder and a cylinder covered with a spacer material. We found differences between the calibration line of the manufacturer and our own measurements, especially when forced convection was involved as the main heat transfer mechanism. The results showed clearly that the calibration method should be chosen according to the intended purpose of use. In addition, we recommend use a thin, light heat flux sensor with good thermal conduction in human subject studies.

  13. 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.

  14. Making the Handoff from Earthquake Hazard Assessments to Effective Mitigation Measures (Invited)

    NASA Astrophysics Data System (ADS)

    Applegate, D.

    2010-12-01

    This year has witnessed a barrage of large earthquakes worldwide with the resulting damages ranging from inconsequential to truly catastrophic. We cannot predict when earthquakes will strike, but we can build communities that are resilient to strong shaking as well as to secondary hazards such as landslides and liquefaction. The contrasting impacts of the magnitude-7 earthquake that struck Haiti in January and the magnitude-8.8 event that struck Chile in April underscore the difference that mitigation and preparedness can make. In both cases, millions of people were exposed to severe shaking, but deaths in Chile were measured in the hundreds rather than the hundreds of thousands that perished in Haiti. Numerous factors contributed to these disparate outcomes, but the most significant is the presence of strong building codes in Chile and their total absence in Haiti. The financial cost of the Chilean earthquake still represents an unacceptably high percentage of that nation’s gross domestic product, a reminder that life safety is the paramount, but not the only, goal of disaster risk reduction measures. For building codes to be effective, both in terms of lives saved and economic cost, they need to reflect the hazard as accurately as possible. As one of four federal agencies that make up the congressionally mandated National Earthquake Hazards Reduction Program (NEHRP), the U.S. Geological Survey (USGS) develops national seismic hazard maps that form the basis for seismic provisions in model building codes through the Federal Emergency Management Agency and private-sector practitioners. This cooperation is central to NEHRP, which both fosters earthquake research and establishes pathways to translate research results into implementation measures. That translation depends on the ability of hazard-focused scientists to interact and develop mutual trust with risk-focused engineers and planners. Strengthening that interaction is an opportunity for the next generation

  15. Gamma heating measurements with proportional counters

    SciTech Connect

    Chiu, H.; Bennett, E.F.; Micklich, B.J.

    1990-05-01

    A new data acquisition technique (the Continuously-varied Bias- voltage Acquisition mode) has been developed and tested for the low-flux broad-energy regime characteristic of existing fusion blanket mock-ups. This method of analysis allows for the acquisition of data spanning several orders of magnitude in energy with a single proportional counter. Utilizing this method, the gamma energy deposition in a mixed neutron and gamma field was measured. 7 refs., 5 figs.

  16. Heat transfer measurements and CFD simulations of an impinging jet

    NASA Astrophysics Data System (ADS)

    Petera, Karel; Dostál, Martin

    2016-03-01

    Heat transport in impinging jets makes a part of many experimental and numerical studies because some similarities can be identified between a pure impingement jet and industrial processes like, for example, the heat transfer at the bottom of an agitated vessel. In this paper, experimental results based on measuring the response to heat flux oscillations applied to the heat transfer surface are compared with CFD simulations. The computational cost of a LES-based approach is usually too high therefore a comparison with less computationally expensive RANS-based turbulence models is made in this paper and a possible improvement of implementing an anisotropic explicit algebraic model for the turbulent heat flux model is evaluated.

  17. Mitigation of divertor heat flux by high-frequency ELM pacing with non-fuel pellet injection in DIII-D

    DOE PAGES

    Bortolon, A.; Maingi, R.; Mansfield, D. K.; ...

    2017-03-23

    Experiments have been conducted on DIII-D investigating high repetition rate injection of non-fuel pellets as a tool for pacing Edge Localized Modes (ELMs) and mitigating their transient divertor heat loads. Effective ELM pacing was obtained with injection of Li granules in different H-mode scenarios, at frequencies 3–5 times larger than the natural ELM frequency, with subsequent reduction of strike-point heat flux. However, in scenarios with high pedestal density (~6 × 1019 m–3), the magnitude of granule triggered ELMs shows a broad distribution, in terms of stored energy loss and peak heat flux, challenging the effectiveness of ELM mitigation. Furthermore, transientmore » heat-flux deposition correlated with granule injections was observed far from the strike-points. As a result, field line tracing suggest this phenomenon to be consistent with particle loss into the mid-plane far scrape-off layer, at toroidal location of the granule injection.« less

  18. Corrections for heat flux measurements taken on launch vehicles

    NASA Astrophysics Data System (ADS)

    Reinarts, Thomas R.; Matson, Monique L.; Walls, Laurie K.

    2002-01-01

    Knowledge of aerothermally induced convective heat transfer and plume induced radiative heat transfer loads is essential to the design of thermal protection systems for launch vehicles. Aerothermal and radiative models are typically calibrated via the data from cylindrical, in-flight, flush-mounted surface heat flux gauges that are exposed to the external thermal and velocity boundary layers as well as thermal radiation. Typically, Schmidt-Boelter gauges, taking advantage of the 1-Dimensional Fourier's law, measure the incident heat flux. This instrumentation, when surrounded by low-conductivity insulation, has an exposed surface temperature significantly lower than the insulation. As a result of this substantial disturbance to the thermal boundary layer, the heat flux incident on the gauge tends to be considerably higher (potentially by factors of 2 or more) than it would have been on the insulation had the calorimeter not been there. In addition, the gauge can receive energy radially from the hotter insulation, contributing to the increase of the indicated heat flux. This paper will present an overview of an effort to model the heat flux gauge under typical flight conditions that includes an installation surrounded by high temperature insulation. The goal is to correct the measurements to reflect the local heat flux on the insulation had the instrument not been present. The three major components of this effort include: 1) a 3-Dimensional computational thermal math model including the internal conduction heat transfer details of a Schmidt-Boelter gauge. 2) a CFD analysis to determine the effects on measurement of the rapidly changing thermal boundary layer over the near step changes in wall temperature, and 3) testing performed on flat plates exposed to an aerothermal environment in the Marshall Space Flight Center (MSFC) Improved Hot Gas Facility (IHGF). A summary of the analytical efforts will be presented, as well as early testing results and preliminary model

  19. Time and Space Resolved Heat Flux Measurements During Nucleate Boiling with Constant Heat Flux Boundary Conditions

    NASA Technical Reports Server (NTRS)

    Yerramilli, Vamsee K.; Myers, Jerry G.; Hussey, Sam W.; Yee, Glenda F.; Kim, Jungho

    2005-01-01

    The lack of temporally and spatially resolved measurements under nucleate bubbles has complicated efforts to fully explain pool-boiling phenomena. The objective of this current work was to acquire time and space resolved temperature distributions under nucleating bubbles on a constant heat flux surface using a microheater array with 100x 100 square microns resolution, then numerically determine the wall to liquid heat flux. This data was then correlated with high speed (greater than l000Hz) visual recordings of The bubble growth and departure from the heater surface acquired from below and from the side of the heater. The data indicate that microlayer evaporation and contact line heat transfer are not major heat transfer mechanisms for bubble growth. The dominant heat transfer mechanism appears to be transient conduction into the liquid as the liquid rewets the wall during the bubble departure process.

  20. Severe accident approach - final report. Evaluation of design measures for severe accident prevention and consequence mitigation.

    SciTech Connect

    Tentner, A. M.; Parma, E.; Wei, T.; Wigeland, R.; Nuclear Engineering Division; SNL; INL

    2010-03-01

    An important goal of the US DOE reactor development program is to conceptualize advanced safety design features for a demonstration Sodium Fast Reactor (SFR). The treatment of severe accidents is one of the key safety issues in the design approach for advanced SFR systems. It is necessary to develop an in-depth understanding of the risk of severe accidents for the SFR so that appropriate risk management measures can be implemented early in the design process. This report presents the results of a review of the SFR features and phenomena that directly influence the sequence of events during a postulated severe accident. The report identifies the safety features used or proposed for various SFR designs in the US and worldwide for the prevention and/or mitigation of Core Disruptive Accidents (CDA). The report provides an overview of the current SFR safety approaches and the role of severe accidents. Mutual understanding of these design features and safety approaches is necessary for future collaborations between the US and its international partners as part of the GEN IV program. The report also reviews the basis for an integrated safety approach to severe accidents for the SFR that reflects the safety design knowledge gained in the US during the Advanced Liquid Metal Reactor (ALMR) and Integral Fast Reactor (IFR) programs. This approach relies on inherent reactor and plant safety performance characteristics to provide additional safety margins. The goal of this approach is to prevent development of severe accident conditions, even in the event of initiators with safety system failures previously recognized to lead directly to reactor damage.

  1. On-line measurement of heat of combustion

    NASA Technical Reports Server (NTRS)

    Chaturvedi, S. K.; Chegini, H.

    1988-01-01

    An experimental method for an on-line measurement of heat of combustion of a gaseous hydrocarbon fuel mixture of unknown composition is developed. It involves combustion of a test gas with a known quantity of air to achieve a predetermined oxygen concentration level in the combustion products. This is accomplished by a feedback controller which maintains the gas volumetric flow rate at a level consistent with the desired oxygen concentration in the products. The heat of combustion is determined from a known correlation with the gas volumetric flow rate. An on-line microcomputer accesses the gas volumetric flow data, and displays the heat of combustion values at desired time intervals.

  2. The nitrogen fate beyond the current nutrient mitigation measures: sustainability of an integrated agriculture

    NASA Astrophysics Data System (ADS)

    Thieu, V.; Billen, G. F.; Garnier, J.; Lancelot, C.; Gypens, N.

    2010-12-01

    Located in the North-Western Europe the terrestrial continuum that includes the Seine, Somme, and Scheldt River basins offers an interesting example of a transborder territory (France, Belgium, and Netherlands) with high-intensity anthropogenic pressures. It well-illustrates the rapid development of modern agriculture in industrialised countries and the resulting severe alteration of water resources and jeopardising the capacity of rural territories to produce drinking water. The corresponding nutrient loads delivered then into the Southern Bight of the North Sea, strongly affect the ecological functioning of the coastal zone. An integrated ‘river-ocean’ assessment, coupling two deterministic models - the SENEQUE RIVESTRAHLER model simulating nutrient dynamic in the drainage network and the MIRO model describing the ecological functioning coastal ecosystem - points out the relevance of current policy based measures (improvement of waste water treatment) to mitigate phosphorous emissions, while the nitrogen pollution related to agriculture will remain critical despite the implementation of classical management measure (good agricultural practices). Therefore and irrespectively of the current political agenda, a more radical alternative is established, consisting of a generalised shift to an integrated agriculture of all agricultural areas in the three basins, excluding the use of synthetically compounded fertilisers and the importation of livestock feed. Such scenario aims at evaluating whether agriculture, by essence, can conciliate (i) the demand for food and feed by local populations, (ii) a good ecological functioning of aquatic ecosystems and (iii) a balanced nutrient status for the adjacent coastal area. This scenario involves an increased livestock density in the Seine and Somme and a decrease in livestock in the Scheldt basin. It leads to a significant reduction of agricultural production that finally brings the three basins closer to autotrophy

  3. Accurate Measurement of Heat Capacity by Differential Scanning Calorimetry

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Experience with high quality heat capacity measurement by differential scanning calorimetry is summarized and illustrated, pointing out three major causes of error: (1) incompatible thermal histories of the sample, reference and blank runs; (2) unstable initial and final isotherms; (3) incompatible differences between initial and final isotherm amplitudes for sample, reference and blank runs. Considering these problems, it is shown for the case of polyoxymethylene that accuracies in heat capacity of 0.1 percent may be possible.

  4. A deterministic evaluation of heat stress mitigation and feed cost under climate change within the smallholder dairy sector.

    PubMed

    York, L; Heffernan, C; Rymer, C; Panda, N

    2016-12-28

    In the global South, dairying is often promoted as a means of poverty alleviation. Yet, under conditions of climate warming, little is known regarding the ability of small-scale dairy producers to maintain production and/or the robustness of possible adaptation options in meeting the challenges presented, particularly heat stress. The authors created a simple, deterministic model to explore the influence of breed and heat stress relief options on smallholder dairy farmers in Odisha, India. Breeds included indigenous Indian (non-descript), low-grade Jersey crossbreed and high-grade Jersey crossbreed. Relief strategies included providing shade, fanning and bathing. The impact of predicted critical global climate parameters, a 2°C and 4°C temperature rise were explored. A feed price scenario was modelled to illustrate the importance of feed in impact estimation. Feed costs were increased by 10% to 30%. Across the simulations, high-grade Jersey crossbreeds maintained higher milk yields, despite being the most sensitive to the negative effects of temperature. Low-capital relief strategies were the most effective at reducing heat stress impacts on household income. However, as feed costs increased the lower-grade Jersey crossbreed became the most profitable breed. The high-grade Jersey crossbreed was only marginally (4.64%) more profitable than the indigenous breed. The results demonstrate the importance of understanding the factors and practical trade-offs that underpin adaptation. The model also highlights the need for hot-climate dairying projects and programmes to consider animal genetic resources alongside environmentally sustainable adaptation measures for greatest poverty impact.

  5. 49 CFR 192.935 - What additional preventive and mitigative measures must an operator take?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... STANDARDS Gas Transmission Pipeline Integrity Management § 192.935 What additional preventive and mitigative... detection systems, replacing pipe segments with pipe of heavier wall thickness, providing additional... supervision of known excavation work. (ii) Collecting in a central database information that is...

  6. Evaporation Measured In Situ by Sensible Heat Balance

    NASA Astrophysics Data System (ADS)

    Heitman, Josh; Xiao, Xinhua; Sauer, Thomas; Ren, Tusheng; Horton, Robert

    2016-04-01

    Measurement of evaporation independent from evapotranspiration remains a major challenge for quantifying water fluxes in the soil-plant-atmosphere system. Methodology based on soil sensible heat balance (SHB) has been developed to measure in situ, sub-surface soil water evaporation with heat-pulse sensors. Soil sensible heat flux and change in heat storage are measured at multiple depths near the soil surface, and a simple energy balance calculation is applied to determine latent heat flux (i.e., evaporation) as a residual. For bare surface conditions, comparison of SHB to micrometerological (Bowen ratio) and micro-lysimeter approaches indicates strong correlation (r2 = 0.96) with near 1:1 relationship and root mean square error of 0.2 mm/d. Recent efforts to apply SHB methodology in row-crop (maize) and vineyard systems demonstrate the potential for quantifying evaporation separate from evapotranspiration. For the maize system, SHB evaporation estimates differed from micro-lysimeters by < 0.2 mm/d. The SHB approach is one of very few measurement approaches that may be applied to partition evaporation from evapotranspiration.

  7. Corrections of Heat Flux Measurements on Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Reinarts, Thomas R.; Matson, Monique L.; Walls, Laurie K.

    2002-01-01

    Knowledge of aerothermally induced convective heat transfer is important in the design of thermal protection systems for launch vehicles. Aerothermal models are typically calibrated via the data from circular, in-flight, flush-mounted surface heat flux gauges exposed to the thermal and velocity boundary layers of the external flow. Typically, copper or aluminum Schmidt- Boelter gauges, which take advantage of the one-dimensional Fourier's law of heat conduction, are used to measure the incident heat flux. This instrumentation, when surrounded by low-conductivity insulation, has a wall temperature significantly lower than the insulation. As a result of this substantial disturbance to the thermal boundary layer, the heat flux incident on the gauge tends to be considerably higher than it would have been on the insulation had the calorimeter not been there. In addition, radial conductive heat transfer from the hotter insulation can cause the calorimeter to indicate heat fluxes higher than actual. An overview of an effort to develop and calibrate gauge correction techniques for both of these effects will be presented.

  8. Basic data for some recent Australian heat-flow measurements

    USGS Publications Warehouse

    Munroe, Robert J.; Sass, J.H.; Milburn, G.T.; Jaeger, J.C.; Tammemagi, H.Y.

    1975-01-01

    This report has been compiled to provide background information and detailed temperature and thermal conductivity data for the heat-flow values reported in Sass, Jaeger, and Munroe (in press). The data were collected as part of a joint heat-flow study by the Australian National University (ANU) and the U.S. Geological Survey (USGS) under the direction of J. C. Jaeger (ANU) and J. H. Sass (USGS). The format is similar to that used for basic data from United States heat-flow determinations (Sass and Munroe, 1974). Each section contains a state map showing the geographic distribution of heat-flow data followed by tables which list individual temperatures, thermal conductivities, and radiogenic heat production values. A companion volume (Bunker and others, 1975) gives details of the heat-production measurements together with individual radioelement concentrations. Localities are arranged in alphabetical order within each state. The methods and techniques of measurements have been described by Sass and others (1971a, b). Unusual methods or procedures which differ markedly from these techniques are noted and described in the comments sections of the tables.

  9. Specific Heat and Second Sound Measurements with the DYNAMIX Instrument

    NASA Technical Reports Server (NTRS)

    Nissen, Joel

    2003-01-01

    In addition to its primary role of studying non-linear heat transport effects near the lambda transition of He-4, the DYNAMX apparatus is suitable for measurements of the specific heat and the velocity of second sound. We plan to take advantage of available time on orbit to make measurements in these areas near to the lambda transition. The specific heat work would be similar to LPE, aimed at improving our knowledge of the singularity in the bulk heat capacity at the transition, but would provide more accurate results close to the transition. It would focus roughly equally on each side of the transition and would be synergistic with the CQ experiment, providing wider-range data at Q = 0. The second sound measurements are made possible by the fast time constant and high resolution of the DYNAMX thermometers, which allow accurate time-of-flight measurements of second sound pulses. It appears possible to measure the second sound velocity to about 1% at a reduced temperature of t = 5x10(exp -8) by averaging over a moderate number of pulses. The data would complement and extend earlier ground-based measurements, leading to improved tests of the theory of static critical phenomena at the lambda transition.

  10. Alternative economic evaluation measures for solar industrial process heat

    SciTech Connect

    Not Available

    1980-07-30

    The measures most commonly used to assist decision-makers in evaluating the economic merits of solar energy projects are described and compared. An example is given to illustrate the economic evaluation measures and the results are applied to a solar industrial process heat project. Four widely used economic measures are: net present value, benefit-cost ratio, internal rate of return, and payback period. (MHR)

  11. Heat Islands

    EPA Pesticide Factsheets

    EPA's Heat Island Effect Site provides information on heat islands, their impacts, mitigation strategies, related research, a directory of heat island reduction initiatives in U.S. communities, and EPA's Heat Island Reduction Program.

  12. Heat flow measurements on the southeast coast of Australia

    USGS Publications Warehouse

    Hyndman, R.D.; Jaeger, J.C.; Sass, J.H.

    1969-01-01

    Three boreholes have been drilled for the Australian National University near the southeast coast of New South Wales, Australia. The heat flows found are 1.1, 1.0, and 1.3 ??cal/cm2sec. The errors resulting from the proximity of the sea and a lake, surface temperature change, conductivity structure and water flow have been examined. The radioactive heat production in some of the intrusive rocks of the area have also been measured. The heat flows are much lower than the values of about 2.0 found elsewhere in south eastern Australia. The lower values appear to be part of a distinct heat flow province in eastern Australia. ?? 1969.

  13. Direct electronic measurement of Peltier cooling and heating in graphene.

    PubMed

    Vera-Marun, I J; van den Berg, J J; Dejene, F K; van Wees, B J

    2016-05-10

    Thermoelectric effects allow the generation of electrical power from waste heat and the electrical control of cooling and heating. Remarkably, these effects are also highly sensitive to the asymmetry in the density of states around the Fermi energy and can therefore be exploited as probes of distortions in the electronic structure at the nanoscale. Here we consider two-dimensional graphene as an excellent nanoscale carbon material for exploring the interaction between electronic and thermal transport phenomena, by presenting a direct and quantitative measurement of the Peltier component to electronic cooling and heating in graphene. Thanks to an architecture including nanoscale thermometers, we detected Peltier component modulation of up to 15 mK for currents of 20 μA at room temperature and observed a full reversal between Peltier cooling and heating for electron and hole regimes. This fundamental thermodynamic property is a complementary tool for the study of nanoscale thermoelectric transport in two-dimensional materials.

  14. Direct electronic measurement of Peltier cooling and heating in graphene

    NASA Astrophysics Data System (ADS)

    Vera-Marun, I. J.; van den Berg, J. J.; Dejene, F. K.; van Wees, B. J.

    2016-05-01

    Thermoelectric effects allow the generation of electrical power from waste heat and the electrical control of cooling and heating. Remarkably, these effects are also highly sensitive to the asymmetry in the density of states around the Fermi energy and can therefore be exploited as probes of distortions in the electronic structure at the nanoscale. Here we consider two-dimensional graphene as an excellent nanoscale carbon material for exploring the interaction between electronic and thermal transport phenomena, by presenting a direct and quantitative measurement of the Peltier component to electronic cooling and heating in graphene. Thanks to an architecture including nanoscale thermometers, we detected Peltier component modulation of up to 15 mK for currents of 20 μA at room temperature and observed a full reversal between Peltier cooling and heating for electron and hole regimes. This fundamental thermodynamic property is a complementary tool for the study of nanoscale thermoelectric transport in two-dimensional materials.

  15. Direct electronic measurement of Peltier cooling and heating in graphene

    PubMed Central

    Vera-Marun, I. J.; van den Berg, J. J.; Dejene, F. K.; van Wees, B. J.

    2016-01-01

    Thermoelectric effects allow the generation of electrical power from waste heat and the electrical control of cooling and heating. Remarkably, these effects are also highly sensitive to the asymmetry in the density of states around the Fermi energy and can therefore be exploited as probes of distortions in the electronic structure at the nanoscale. Here we consider two-dimensional graphene as an excellent nanoscale carbon material for exploring the interaction between electronic and thermal transport phenomena, by presenting a direct and quantitative measurement of the Peltier component to electronic cooling and heating in graphene. Thanks to an architecture including nanoscale thermometers, we detected Peltier component modulation of up to 15 mK for currents of 20 μA at room temperature and observed a full reversal between Peltier cooling and heating for electron and hole regimes. This fundamental thermodynamic property is a complementary tool for the study of nanoscale thermoelectric transport in two-dimensional materials. PMID:27161186

  16. Time and Space Resolved Heat Transfer Measurements Under Nucleate Bubbles with Constant Heat Flux Boundary Conditions

    NASA Technical Reports Server (NTRS)

    Myers, Jerry G.; Hussey, Sam W.; Yee, Glenda F.; Kim, Jungho

    2003-01-01

    Investigations into single bubble pool boiling phenomena are often complicated by the difficulties in obtaining time and space resolved information in the bubble region. This usually occurs because the heaters and diagnostics used to measure heat transfer data are often on the order of, or larger than, the bubble characteristic length or region of influence. This has contributed to the development of many different and sometimes contradictory models of pool boiling phenomena and dominant heat transfer mechanisms. Recent investigations by Yaddanapyddi and Kim and Demiray and Kim have obtained time and space resolved heat transfer information at the bubble/heater interface under constant temperature conditions using a novel micro-heater array (10x10 array, each heater 100 microns on a side) that is semi-transparent and doubles as a measurement sensor. By using active feedback to maintain a state of constant temperature at the heater surface, they showed that the area of influence of bubbles generated in FC-72 was much smaller than predicted by standard models and that micro-conduction/micro-convection due to re-wetting dominated heat transfer effects. This study seeks to expand on the previous work by making time and space resolved measurements under bubbles nucleating on a micro-heater array operated under constant heat flux conditions. In the planned investigation, wall temperature measurements made under a single bubble nucleation site will be synchronized with high-speed video to allow analysis of the bubble energy removal from the wall.

  17. Examples of cooler reflective streets for urban heat-island mitigation : Portland cement concrete and chip seals

    SciTech Connect

    Pomerantz, M.; Akbari, H.; Chang, S.-C.; Levinson, R.; Pon, B.

    2003-04-30

    Part of the urban heat island effect can be attributed to dark pavements that are commonly used on streets and parking lots. In this paper we consider two light colored, hence cooler, alternative paving materials that are in actual use in cities today. These are Portland cement concrete (PCC) pavements and chip seals. We report measurements of the albedos of some PCC and chip sealed pavements in the San Francisco Bay Area. The albedos of the PCC pavements ranged from about 0.18 to 0.35. The temperatures of some PCC pavements are also measured and calculated. We then consider how the albedos of the constituent materials of the PCC (stone, sand and cement) contribute to the albedos of the resulting finished concrete. The albedos of a set of chip sealed pavements in San Jose, CA, were measured and correlated with the times of their placement. It is found that the albedos decrease with age (and use) but remain higher than that of standard asphalt concrete (AC) for about five years. After t hat, the albedos of the chip seals are about 0.12, similar to aged AC. The fact that many PCC pavements have albedos at least twice as high as aged AC suggests that it is possible to have pavement albedos that remain high for many years.

  18. Are changes in weather masking the efficacy of measures aimed at mitigating diffuse pollution?

    NASA Astrophysics Data System (ADS)

    Mellander, Per-Erik; Jordan, Phil; Shore, Mairead; McDonald, Noeleen; Shortle, Ger

    2016-04-01

    Interpretations of the efficacy of mitigation measures for reducing nitrogen (N) and phosphorus (P) losses from agricultural sources to water bodies are challenged by the temporal variability of air temperature and rainfall. Influences are different depending on flow controls, associated time lags and nutrient transformations that may occur along the pathways. In Europe weather patterns and trends are influenced by large-scale weather systems over the North Atlantic. One of the most prominent teleconnection patterns that affect the weather across all seasons is the North Atlantic Oscillation (NAO). In northwestern Europe a positive phase in the NAO index over the winter period is often associated with elevated air temperatures in summer and more frequent large rain events in winter than normal. The objective of this study was to investigate the catchment-scale influences and relationships of naturally altered hydro-meteorological processes on the diffuse N and P losses to waters, in order to distinguish natural climate effects from those caused by adaptive management (increased agricultural intensity, decreased nutrient use etc.). Here we present six years of monthly nitrate-N and total reactive P concentrations in stream water (aggregated from sub-hourly monitoring) in six, ca. 10 km2, Irish agricultural catchments with different hydrological flow controls and land use. The locations of the catchments make them susceptible to sudden and/or seasonal shifts in weather. Changes in long term air temperatures and rainfall were investigated and annual N and P concentrations were compared to the NAO. During the monitored period (2009-2015) there was a steady increase in wintertime NAO index, reaching positive values in recent years, resulting in higher air temperatures and more frequent large rain events in winter. In some settings annual N and/or P concentrations were positively correlated to the three-year moving average NAO index (R2 > 0.90). Catchments with free

  19. Measuring personal heat exposure in an urban and rural environment

    PubMed Central

    Bernhard, Molly C; Kent, Shia T; Sloan, Meagan E; Evans, Mary B; McClure, Leslie A; Gohlke, Julia M

    2014-01-01

    Previous studies have linked heat waves to adverse health outcomes using ambient temperature as a proxy for estimating exposure. The goal of the present study was to test a method for determining personal heat exposure. An occupationally exposed group (urban groundskeepers in Birmingham, AL, USA N=21), as well as urban and rural community members from Birmingham, AL (N=30) or west central AL (N=30) wore data logging temperature and light monitors clipped to the shoe for 7 days during the summer of 2012. We found that a temperature monitor clipped to the shoe provided a comfortable and feasible method for recording personal heat exposure. Ambient temperature (°C) recorded at the nearest weather station was significantly associated with personal heat exposure [β 0.37, 95%CI (0.35, 0.39)], particularly in groundskeepers who spent more of their total time outdoors [β 0.42, 95%CI (0.39, 0.46)]. Factors significantly associated with lower personal heat exposure include reported time indoors [β −2.02, 95%CI (−2.15, −1.89)], reported income > 20K [β −1.05, 95%CI (−1.79, −0.30)], and measured % body fat [β −0.07, 95%CI (−0.12, −0.02)]. There were significant associations between income and % body fat with lower indoor and nighttime exposures, but not with outdoor heat exposure, suggesting modifications of the home thermal environment play an important role in determining overall heat exposure. Further delineation of the effect of personal characteristics on heat exposure may help to develop targeted strategies for preventing heat-related illness. PMID:25617601

  20. Measuring personal heat exposure in an urban and rural environment.

    PubMed

    Bernhard, Molly C; Kent, Shia T; Sloan, Meagan E; Evans, Mary B; McClure, Leslie A; Gohlke, Julia M

    2015-02-01

    Previous studies have linked heat waves to adverse health outcomes using ambient temperature as a proxy for estimating exposure. The goal of the present study was to test a method for determining personal heat exposure. An occupationally exposed group (urban groundskeepers in Birmingham, AL, USA N=21), as well as urban and rural community members from Birmingham, AL (N=30) or west central AL (N=30) wore data logging temperature and light monitors clipped to the shoe for 7 days during the summer of 2012. We found that a temperature monitor clipped to the shoe provided a comfortable and feasible method for recording personal heat exposure. Ambient temperature (°C) recorded at the nearest weather station was significantly associated with personal heat exposure [β 0.37, 95%CI (0.35, 0.39)], particularly in groundskeepers who spent more of their total time outdoors [β 0.42, 95%CI (0.39, 0.46)]. Factors significantly associated with lower personal heat exposure include reported time indoors [β -2.02, 95%CI (-2.15, -1.89)], reported income>20K [β -1.05, 95%CI (-1.79, -0.30)], and measured % body fat [β -0.07, 95%CI (-0.12, -0.02)]. There were significant associations between income and % body fat with lower indoor and nighttime exposures, but not with outdoor heat exposure, suggesting modifications of the home thermal environment play an important role in determining overall heat exposure. Further delineation of the effect of personal characteristics on heat exposure may help to develop targeted strategies for preventing heat-related illness.

  1. Measurement of heat pump processes induced by laser radiation

    NASA Technical Reports Server (NTRS)

    Garbuny, M.; Henningsen, T.

    1983-01-01

    A series of experiments was performed in which a suitably tuned CO2 laser, frequency doubled by a Tl3AsSe37 crystal, was brought into resonance with a P-line or two R-lines in the fundamental vibration spectrum of CO. Cooling or heating produced by absorption in CO was measured in a gas-thermometer arrangement. P-line cooling and R-line heating could be demonstrated, measured, and compared. The experiments were continued with CO mixed with N2 added in partial pressures from 9 to 200 Torr. It was found that an efficient collisional resonance energy transfer from CO to N2 existed which increased the cooling effects by one to two orders of magnitude over those in pure CO. Temperature reductions in the order of tens of degrees Kelvin were obtained by a single pulse in the core of the irradiated volume. These measurements followed predicted values rather closely, and it is expected that increase of pulse energies and durations will enhance the heat pump effects. The experiments confirm the feasibility of quasi-isentropic engines which convert laser power into work without the need for heat rejection. Of more immediate potential interest is the possibility of remotely powered heat pumps for cryogenic use, such applications are discussed to the extent possible at the present stage.

  2. Simultaneous specific heat and thermal conductivity measurement of individual nanostructures

    NASA Astrophysics Data System (ADS)

    Zheng, Jianlin; Wingert, Matthew C.; Moon, Jaeyun; Chen, Renkun

    2016-08-01

    Fundamental phonon transport properties in semiconductor nanostructures are important for their applications in energy conversion and storage, such as thermoelectrics and photovoltaics. Thermal conductivity measurements of semiconductor nanostructures have been extensively pursued and have enhanced our understanding of phonon transport physics. Specific heat of individual nanostructures, despite being an important thermophysical parameter that reflects the thermodynamics of solids, has remained difficult to characterize. Prior measurements were limited to ensembles of nanostructures in which coupling and sample inhomogeneity could play a role. Herein we report the first simultaneous specific heat and thermal conductivity measurements of individual rod-like nanostructures such as nanowires and nanofibers. This technique is demonstrated by measuring the specific heat and thermal conductivity of single ˜600-700 nm diameter Nylon-11 nanofibers (NFs). The results show that the thermal conductivity of the NF is increased by 50% over the bulk value, while the specific heat of the NFs exhibits bulk-like behavior. We find that the thermal diffusivity obtained from the measurement, which is related to the phonon mean free path (MFP), decreases with temperature, indicating that the intrinsic phonon Umklapp scattering plays a role in the NFs. This platform can also be applied to one- and two- dimensional semiconductor nanostructures to probe size effects on the phonon spectra and other transport physics.

  3. The contribution of urbanization to recent extreme heat events and white roof mitigation strategy in the Beijing-Tianjin-Hebei metropolitan area

    NASA Astrophysics Data System (ADS)

    Wang, Mingna

    2015-04-01

    The UHI effect can aggravate summertime heat waves and strongly influence human comfort and health, leading to greater mortality in metropolitan areas. Many geo-engineering technological strategies have been proposed to mitigate climate warming, and for the UHI, increasing the albedo of artificial urban surfaces (rooftops or pavements) has been considered a lucrative and effective way to cool cities. The objective of this work is to quantify the contribution of urbanization to recent extreme heat events of the early 21st century in the Beijing-Tianjin-Hebei metropolitan area, using the mesoscale WRF model coupled with a single urban canopy model and actual urban land cover datasets. This work also investigates a simulation of the regional effects of white roof technology by increasing the albedo of urban areas in the urban canopy model to mitigate the urban heat island, especially in extreme heat waves. The results show that urban land use characteristics that have evolved over the past ~20 years in the Beijing-Tianjin-Hebei metropolitan area have had a significant impact on the extreme temperatures occurring during extreme heat events. Simulations show that new urban development has caused an intensification and expansion of the areas experiencing extreme heat waves with an average increase in temperature of approximately 0.60°C. This change is most obvious at night with an increase up to 0.95°C, for which the total contribution of anthropogenic heat is 34%. We also simulate the effects of geo-engineering strategies increasing the albedo of urban roofs. White roofs reflect a large fraction of incoming sunlight in the daytime, which reduced the net radiation so that the roof surface keep at a lower temperature than regular solar-absorptive roofs. Urban net radiation decreases by approximately 200 W m-2 at local noon because of high solar reflectance of white roofs, which cools the daytime urban temperature afer sunrise, with the largest decrease of almost -0.80

  4. A review of monitoring approaches and outcomes of surface water quality mitigation measures in meso-scale agricultural catchments

    NASA Astrophysics Data System (ADS)

    Melland, Alice; Jordan, Phil; Murphy, Paul; Mellander, Per-Erik; Shortle, Ger

    2013-04-01

    Critical for an informative feedback loop from scientific monitoring of biophysical change, to making and implementing suitable policy to effect the desired change, are both accurate measurement of biophysical change, and measurement or modelling of the causes of change. For example the European Environment Agency uses the DPSIR framework to assess change in the state (S) of natural resources due to changes in specific drivers (D) and pressures (P) that can have an impact (I) and are the focus of policy responses (R). This paper provides a review of meso-catchment scale studies worldwide that have measured the impacts of agricultural land management practice on surface water quality. Approaches for measuring water quality impacts of agricultural mitigation practices in meso-catchments (1-100 km2) ranged from measuring water quality over a time series, such as before and after a land management change, or over a spatial series such as in paired catchments with and without agricultural practice change (or over a gradient of practices or catchment types), and by cause and effect studies that measure sources, pathways and impacts of practices. Agricultural mitigation measures had no measurable effect, or positive, or negative effects on water quality over periods of 3 to 20 years. In most catchments where beneficial effects of mitigation measures were successfully measured, combinations of measures that address nutrient or pollutant sources, pathways, delivery and impact have been implemented. Successful farm measures included substantial reductions in the intensity of the farming systems, improved engineering and crop management to reduce runoff and drainage transport of nutrients and sediment, as well as high rates of implementation of measures across the catchments. In many cases, the potential to measure improvement in one or more water quality indicators was limited by the impact of a few management or weather events. Reasons that water quality did not improve in

  5. Construction and measurements of an improved vacuum-swing-adsorption radon-mitigation system

    SciTech Connect

    Street, J. Bunker, R.; Dunagan, C.; Loose, X.; Schnee, R. W.; Stark, M.; Sundarnath, K.; Tronstad, D.

    2015-08-17

    In order to reduce backgrounds from radon-daughter plate-out onto detector surfaces, an ultra-low-radon cleanroom is being commissioned at the South Dakota School of Mines and Technology. An improved vacuum-swing-adsorption radon mitigation system and cleanroom build upon a previous design implemented at Syracuse University that achieved radon levels of ∼0.2 Bq m{sup −3}. This improved system will employ a better pump and larger carbon beds feeding a redesigned cleanroom with an internal HVAC unit and aged water for humidification. With the rebuilt (original) radon mitigation system, the new low-radon cleanroom has already achieved a > 300× reduction from an input activity of 58.6 ± 0.7 Bq m{sup −3} to a cleanroom activity of 0.13 ± 0.06 Bq m{sup −3}.

  6. Heat Fluxes and Evaporation Measurements by Multi-Function Heat Pulse Probe: a Laboratory Experiment

    NASA Astrophysics Data System (ADS)

    Sharma, V.; Ciocca, F.; Hopmans, J. W.; Kamai, T.; Lunati, I.; Parlange, M. B.

    2012-04-01

    Multi Functional Heat Pulse Probes (MFHPP) are multi-needles probes developed in the last years able to measure temperature, thermal properties such as thermal diffusivity and volumetric heat capacity, from which soil moisture is directly retrieved, and electric conductivity (through a Wenner array). They allow the simultaneous measurement of coupled heat, water and solute transport in porous media, then. The use of only one instrument to estimate different quantities in the same volume and almost at the same time significantly reduces the need to interpolate different measurement types in space and time, increasing the ability to study the interdependencies characterizing the coupled transports, especially of water and heat, and water and solute. A three steps laboratory experiment is realized at EPFL to investigate the effectiveness and reliability of the MFHPP responses in a loamy soil from Conthey, Switzerland. In the first step specific calibration curves of volumetric heat capacity and thermal conductivity as function of known volumetric water content are obtained placing the MFHPP in small samplers filled with the soil homogeneously packed at different saturation degrees. The results are compared with literature values. In the second stage the ability of the MFHPP to measure heat fluxes is tested within a homemade thermally insulated calibration box and results are matched with those by two self-calibrating Heatflux plates (from Huxseflux), placed in the same box. In the last step the MFHPP are used to estimate the cumulative subsurface evaporation inside a small column (30 centimeters height per 8 centimeters inner diameter), placed on a scale, filled with the same loamy soil (homogeneously packed and then saturated) and equipped with a vertical array of four MFHPP inserted close to the surface. The subsurface evaporation is calculated from the difference between the net sensible heat and the net heat storage in the volume scanned by the probes, and the

  7. Measurements of ocean surface kinematics and heat flux

    NASA Astrophysics Data System (ADS)

    Veron, Fabrice; Melville, Ken

    2003-11-01

    The top few meters of the oceanic boundary layer play a critical role in the transfers of momentum, gas, mass and heat between the atmosphere and the ocean. These exchanges must necessarily transfer through the surface, and presumably, the rates at which they do are influence by the dynamics of the surface layer. Heat flux in particular is regulated by the thin surface thermal layer which, at most, is only a few millimeter thick. We are specifically interested in the structure of the thermal layer and the influence of the surface turbulence on the flux of heat through the air-sea boundary. Using active and passive infrared imaging, we were able to collect high temporal and spatial resolution images, yielding the Lagrangian surface velocity and temperature fields over small areas of a few square meters. We have applied cross-correlation techniques (typically used for Particle Image Velocimetry) on the passive infrared images and obtained high-resolution surface velocity fields. Using the displacement and the distortion of the actively laid down heat pattern, we also have been able to recover the surface velocity, shear strain, vorticity, and divergence. In addition, the data show that the heat flux appears to be correlated the surface vorticity. With the penetration depth of infrared radiation at these wavelengths being a few microns, these techniques appear to be extremely promising for measuring ocean surface turbulence confined within the thermal boundary layer. We will discuss the results in the context of air sea heat flux and ocean surface turbulence.

  8. Commercial Instrument for Automated Specific Heat Measurements at Millikelvin Temperatures

    NASA Astrophysics Data System (ADS)

    Neils, W. K.; Martien, Dinesh; Bauer, E. D.; Mixson, D.; Hur, N.; Thompson, J. D.; Sarrao, J. L.

    2006-09-01

    The specific heat of CeRhIn5-xSnx was measured down to 55 mK using a novel, fully automated measurement system. The system consists of a dilution refrigerator designed to operate in a Quantum Design Physical Property Measurement System, a calorimeter optimized for millikelvin temperatures and very low addenda heat capacity, electronics to perform the measurement, and software to automate the measurement. The compound CeRhIn5 exhibits antiferromagnetism at a Neel temperature of TN = 3.8 K which is suppressed at a critical pressure Pc ˜ 25 kbar, indicating a quantum critical point (QCP). At pressures above ˜ 15 kbar, CeRhIn5 exhibits antiferromagnetism and superconductivity simultaneously. Measurement of the specific heat of CeRhIn5-xSnx in magnetic field offers an additional tool to probe the antiferromagnetic QCP. Preliminary measurements up to H = 3 T for CeRhIn4.77Sn0.23 are reported.

  9. Measurement of the Convective Heat-Transfer Coefficient

    ERIC Educational Resources Information Center

    Conti, Rosaria; Gallitto, Aurelio Agliolo; Fiordilino, Emilio

    2014-01-01

    We propose an experiment for investigating how objects cool down toward the thermal equilibrium with their surroundings. We describe the time dependence of the temperature difference of the cooling objects and the environment with an exponential decay function. By measuring the thermal constant t, we determine the convective heat-transfer…

  10. Heat transport measurements in turbulent rotating Rayleigh-Benard convection

    SciTech Connect

    Ecke, Robert E; Liu, Yuanming

    2008-01-01

    We present experimental heat transport measurements of turbulent Rayleigh-Benard convection with rotation about a vertical axis. The fluid, water with Prandtl number ({sigma}) about 6, was confined in a cell which had a square cross section of 7.3 cm x 7.3 cm and a height of 9.4 cm. Heat transport was measured for Rayleigh numbers 2 x 10{sup 5} < Ra < 5 x 10{sup 8} and Taylor numbers 0 < Ta < 5 x 10{sup 9}. We show the variation of normalized heat transport, the Nusselt number, at fixed dimensional rotation rate {Omega}{sub D}, at fixed Ra varying Ta, at fixed Ta varying Ra, and at fixed Rossby number Ro. The scaling of heat transport in the range 10{sup 7} to about 10{sup 9} is roughly 0.29 with a Ro dependent coefficient or equivalently is also well fit by a combination of power laws of the form a Ra{sup 1/5} + b Ra{sup 1/3} . The range of Ra is not sufficient to differentiate single power law or combined power law scaling. The overall impact of rotation on heat transport in turbulent convection is assessed.

  11. Scanning measurement of Seebeck coefficient of a heated sample

    DOEpatents

    Snyder, G. Jeffrey; Iwanaga, Shiho

    2016-04-19

    A novel scanning Seebeck coefficient measurement technique is disclosed utilizing a cold scanning thermocouple probe tip on heated bulk and thin film samples. The system measures variations in the Seebeck coefficient within the samples. The apparatus may be used for two dimensional mapping of the Seebeck coefficient on the bulk and thin film samples. This technique can be utilized for detection of defective regions, as well as phase separations in the sub-mm range of various thermoelectric materials.

  12. Corrections for Heat Flux Measurements Taken on Launch Vehicles

    NASA Astrophysics Data System (ADS)

    Reinarts, Thomas R.; Ford, Danielle M.

    2004-02-01

    Knowledge of aerothermally induced convective heat transfer and plume induced radiative heat transfer loads is essential to the design of thermal protection systems (TPS) for launch vehicles. Aerothermal and radiative models are typically calibrated via the data from cylindrical, in-flight, flush-mounted surface heat flux gauges that are exposed to the external thermal and velocity boundary layers as well as thermal radiation. Typically, Schmidt-Boelter gauges, taking advantage of the 1-Dimensional Fourier's law, measure the incident heat flux. This instrumentation, when surrounded by low-conductivity insulation, has an exposed surface temperature significantly lower than the insulation. As a result of this substantial disturbance to the thermal boundary layer, the heat flux incident on the gauge tends to be considerably higher (potentially by factors of 2 or more) than it would have been on the insulation had the calorimeter not been there. In addition, the gauge can receive energy radially from the hotter insulation, contributing to the increase of the indicated heat flux. This paper will present an overview of an effort to model the heat flux gauge under typical flight conditions that includes an installation surrounded by high temperature insulation. The goal is to correct the measurements to reflect the local heat flux on the insulation had the instrument not been present. The three major components of this effort include: 1) a three-dimensional computational thermal math model including the internal conduction heat transfer details of a Schmidt-Boelter gauge, 2) a two-dimensional Navier-Stokes computational fluid dynamics (CFD) analysis to determine the effects on measurement of the rapidly changing thermal boundary layer over the near step changes in wall temperature, and 3) testing performed on flat plates exposed to an aerothermal environment in the Marshall Space Flight Center (MSFC) Improved Hot Gas Facility (IHGF). A brief summary of calibration issues

  13. Measurement of a surface heat flux and temperature

    NASA Technical Reports Server (NTRS)

    Davis, R. M.; Antoine, G. J.; Diller, T. E.; Wicks, A. L.

    1994-01-01

    The Heat Flux Microsensor is a new sensor which was recently patented by Virginia Tech and is just starting to be marketed by Vatell Corp. The sensor is made using the thin-film microfabrication techniques directly on the material that is to be measured. It consists of several thin-film layers forming a differential thermopile across a thermal resistance layer. The measured heat flux q is proportional to the temperature difference across the resistance layer q= k(sub g)/delta(sub g) x (t(sub 1) - T(sub 2)), where k(sub g) is the thermal conductivity and delta (sub g) is the thickness of the thermal resistance layer. Because the gages are sputter coated directly onto the surface, their total thickness is less than 2 micrometers, which is two orders of magnitude thinner than previous gages. The resulting temperature difference across the thermal resistance layer (delta is less than 1 micrometer) is very small even at high heat fluxes. To generate a measurable signal many thermocouple pairs are put in series to form a differential thermopile. The combination of series thermocouple junctions and thin-film design creates a gage with very attractive characteristics. It is not only physically non-intrusive to the flow, but also causes minimal disruption of the surface temperature. Because it is so thin, the response time is less than 20 microsec. Consequently, the frequency response is flat from 0 to over 50 kHz. Moreover, the signal of the Heat Flux Microsensor is directly proportional to the heat flux. Therefore, it can easily be used in both steady and transient flows, and it measures both the steady and unsteady components of the surface heat flux. A version of the Heat Flux Microsensor has been developed to meet the harsh demands of combustion environments. These gages use platinum and platinum-10 percent rhodium as the thermoelectric materials. The thermal resistance layer is silicon monoxide and a protective coating of Al2O3 is deposited on top of the sensor. The

  14. Measurements of Ocean surface kinematics and heat transfer

    NASA Astrophysics Data System (ADS)

    Veron, Fabrice; Melville, Ken

    2002-11-01

    The top few meters of the oceanic boundary layer play a critical role in the transfers of momentum, gas, mass and heat between the atmosphere and the ocean. These exchanges must necessarily transfer through the surface, and presumably, the rates at which they do are influence by the dynamics of the surface layer. Heat flux in particular is regulated by the thin surface thermal layer which, at most, is only a few millimeter thick. We are specifically interested in the influence of small coherent structures of the surface turbulence on the heat flux. Using active and passive infrared imaging, we were able to measure the evolution the surface velocity and temperature fields over small areas of a few square meters. Preliminary data show that it is possible to apply cross-correlation techniques (typically used for Particle Image Velocimetry) on the passive infrared images. This yields high-resolution surface velocity fields. Using active marking of the surface with an infrared CO2 laser, we have shown that it is possible to also directly recover the surface velocity, but also, by marking appropriate patterns on the surface we have been able to measure the shear strain, vorticity, and surface divergence. With the penetration depth of infrared radiation at these wavelengths being a few microns, these techniques appear to be extremely promising for measuring ocean surface turbulence confined within the thermal boundary layer. We will discuss the results in the context of air sea heat flux and ocean surface turbulence.

  15. Directly Measured Heating Rates of a Tropical Subvisible Cirrus Cloud

    NASA Technical Reports Server (NTRS)

    Bucholtz, Anthongy; Hlavka, Dennis L.; McGill, Matthew J.; Schmidt, K. Sebastian; Pilewskie, Peter; Davis, Sean M.; Reid, Elizabeth A.; Walker, Annette L.

    2010-01-01

    We present the first direct measurements of the infrared and solar heating rates of a tropical subvisible cirrus (SVC) cloud sampled off the east coast of Nicaragua on 25 July 2007 by the NASA ER-2 aircraft during the Tropical Composition, Cloud and Climate Coupling Experiment (TC4). On this day a persistent thin cirrus layer, with mostly clear skies underneath, was detected in real time by the cloud lidar on the ER-2, and the aircraft was directed to profile down through the SVC. Measurements of the net broadband infrared irradiance and spectrally integrated solar irradiance above, below, and through the SVC are used to determine the infrared and solar heating rates of the cloud. The lidar measurements show that the variable SVC layer was located between approximately 13 and 15 km. Its midvisible optical depth varied from 0.01 to 0.10 with a mean of 0.034 +/- 0.033. Its depolarization ratio was approximately 0.4, indicative of ice clouds. From the divergence of the measured net irradiances the infrared heating rate of the SVC was determined to be approximately 2.50 - 3.24 K/d and the solar heating rate was found to be negligible. These values are consistent with previous indirect observations of other SVC and with model-generated heating rates of SVC with similar optical depths. This study illustrates the utility and potential of the profiling sampling strategy employed here. A more fully instrumented high-altitude aircraft that also included in situ cloud and aerosol probes would provide a comprehensive data set for characterizing both the radiative and microphysical properties of these ubiquitous tropical clouds

  16. Erasure temperature measurements of heat assisted magnetic recording media

    NASA Astrophysics Data System (ADS)

    Chen, Y. J.; Yang, H. Z.; Leong, S. H.; Cher, K. M.; Hu, J. F.; Sethi, P.; Lew, W. S.

    2015-05-01

    For heat assisted magnetic recording (HAMR) media development, measurement of erasure temperature (Te) is interesting and important for practical HAMR testing and applications. Here, we present an investigation on Te measurements of L10 ordered FePt granular HAMR media made using a Laser Heating (LH) method on a home-built HAMR write test system versus that from a bulk heating approach. The HAMR write test system provides HAMR writing, micro-MOKE (magneto-optical Kerr effect) signal detection, and MOKE imaging functions at the same testing spot in one single system. Magnetic force microscopy (MFM) and magnetic Kerr microscopy observations of the scanning laser induced degradation/erasure/demagnetization of the pre-recorded magnetic patterns on disk media (over a wide area of a few hundreds of μm2) show that the magnetic (MFM and Kerr signal) amplitude of the pre-recorded magnetic patterns decreases slowly with increasing laser power (Pw) (/temperature rise) for Pw ≲ 66 mW and then drops sharply to nearly zero for Pw ≥ ˜72 mW (the laser power corresponding to complete thermal erasure when the media temperature is ˜Te). It was further found that this trend of magnetic amplitude reduction with increased Pw is similar to that from magnetic amplitude decrease of pre-recorded magnetic patterns with increased bulk heating temperature. The temperature for complete erasure at laser power, Pw = 72 mW for the LH method, corresponds therefore to ˜650 K (≈Te) for the bulk heating methods. Besides fast measurement, LH (as a comparable and viable approach for erasure measurement) is dynamic, localized, and has time scales closer to practical HAMR situation.

  17. Coupling Vector-host Dynamics with Weather Geography and Mitigation Measures to Model Rift Valley Fever in Africa

    PubMed Central

    McMahon, B.H.; Manore, C.A.; Hyman, J.M.; LaBute, M.X.; Fair, J.M.

    2015-01-01

    We present and characterize a multi-host epidemic model of Rift Valley fever (RVF) virus in East Africa with geographic spread on a network, rule-based mitigation measures, and mosquito infection and population dynamics. Susceptible populations are depleted by disease and vaccination and are replenished with the birth of new animals. We observe that the severity of the epidemics is strongly correlated with the duration of the rainy season and that even severe epidemics are abruptly terminated when the rain stops. Because naturally acquired herd immunity is established, total mortality across 25 years is relatively insensitive to many mitigation approaches. Strong reductions in cattle mortality are expected, however, with sufficient reduction in population densities of either vectors or susceptible (ie. unvaccinated) hosts. A better understanding of RVF epidemiology would result from serology surveys to quantify the importance of herd immunity in epidemic control, and sequencing of virus from representative animals to quantify the realative importance of transportation and local reservoirs in nucleating yearly epidemics. Our results suggest that an effective multi-layered mitigation strategy would include vector control, movement control, and vaccination of young animals yearly, even in the absence of expected rainfall. PMID:25892858

  18. Method for Accurate Surface Temperature Measurements During Fast Induction Heating

    NASA Astrophysics Data System (ADS)

    Larregain, Benjamin; Vanderesse, Nicolas; Bridier, Florent; Bocher, Philippe; Arkinson, Patrick

    2013-07-01

    A robust method is proposed for the measurement of surface temperature fields during induction heating. It is based on the original coupling of temperature-indicating lacquers and a high-speed camera system. Image analysis tools have been implemented to automatically extract the temporal evolution of isotherms. This method was applied to the fast induction treatment of a 4340 steel spur gear, allowing the full history of surface isotherms to be accurately documented for a sequential heating, i.e., a medium frequency preheating followed by a high frequency final heating. Three isotherms, i.e., 704, 816, and 927°C, were acquired every 0.3 ms with a spatial resolution of 0.04 mm per pixel. The information provided by the method is described and discussed. Finally, the transformation temperature Ac1 is linked to the temperature on specific locations of the gear tooth.

  19. Temperature measurements using multicolor pyrometry in thermal radiation heating environments

    SciTech Connect

    Fu, Tairan; Liu, Jiangfan; Duan, Minghao; Zong, Anzhou

    2014-04-15

    Temperature measurements are important for thermal-structural experiments in the thermal radiation heating environments such as used for thermal-structural stress analyses. This paper describes the use of multicolor pyrometry for the measurements of diffuse surfaces in thermal radiation environments that eliminates the effects of background radiation reflections and unknown emissivities based on a least-squares algorithm. The near-infrared multicolor pyrometer had a spectral range of 1100–2400 nm, spectrum resolution of 6 nm, maximum sampling frequency of 2 kHz, working distance of 0.6 m to infinity, temperature range of 700–1700 K. The pyrometer wavelength response, nonlinear intensity response, and spectral response were all calibrated. The temperature of a graphite sample irradiated by quartz lamps was then measured during heating and cooling using the least-squares algorithm based on the calibrated irradiation data. The experiments show that higher temperatures and longer wavelengths are more suitable for the thermal measurements in the quartz lamp radiation heating system. This analysis provides a valuable method for temperature measurements of diffuse surfaces in thermal radiation environments.

  20. Tomato yellow leaf curl virus infection mitigates the heat stress response of plants grown at high temperatures.

    PubMed

    Ghandi, Anfoka; Adi, Moshe; Lilia, Fridman; Linoy, Amrani; Or, Rotem; Mikhail, Kolot; Mouhammad, Zeidan; Henryk, Czosnek; Rena, Gorovits

    2016-01-21

    Cultured tomatoes are often exposed to a combination of extreme heat and infection with Tomato yellow leaf curl virus (TYLCV). This stress combination leads to intense disease symptoms and yield losses. The response of TYLCV-susceptible and resistant tomatoes to heat stress together with viral infection was compared. The plant heat-stress response was undermined in TYLCV infected plants. The decline correlated with the down-regulation of heat shock transcription factors (HSFs) HSFA2 and HSFB1, and consequently, of HSF-regulated genes Hsp17, Apx1, Apx2 and Hsp90. We proposed that the weakened heat stress response was due to the decreased capacity of HSFA2 to translocate into the nuclei of infected cells. All the six TYLCV proteins were able to interact with tomato HSFA2 in vitro, moreover, coat protein developed complexes with HSFA2 in nuclei. Capturing of HSFA2 by viral proteins could suppress the transcriptional activation of heat stress response genes. Application of both heat and TYLCV stresses was accompanied by the development of intracellular large protein aggregates containing TYLCV proteins and DNA. The maintenance of cellular chaperones in the aggregated state, even after recovery from heat stress, prevents the circulation of free soluble chaperones, causing an additional decrease in stress response efficiency.

  1. Measurement of the Specific Heat Using a Gravity Cancellation Approach

    NASA Technical Reports Server (NTRS)

    Zhong, Fang

    2003-01-01

    The specific heat at constant volume C(sob V) of a simple fluid diverges near its liquid-vapor critical point. However, gravity-induced density stratification due to the divergence of isothermal susceptibility hinders the direct comparison of the experimental data with the predictions of renormalization group theory. In the past, a microgravity environment has been considered essential to eliminate the density stratification. We propose to perform specific heat measurements of He-3 on the ground using a method to cancel the density stratification. A He-3 fluid layer will be heated from below, using the thermal expansion of the fluid to cancel the hydrostatic compression. A 6% density stratification at a reduced temperature of 10(exp -5) can be cancelled to better than 0.1% with a steady 1.7 micro K temperature difference across a 0.05 cm thick fluid layer. A conventional AC calorimetry technique will be used to determine the heat capacity. The minimized bulk density stratification with a relaxation time 6500 sec at a reduced temperature of 10(exp -5) will stay unchanged during 1 Hz AC heating. The smear of the specific heat divergence due to the temperature difference across the cell is about 0.1% at a reduced temperature of 10(exp -6). The combination of using High Resolution Thermometry with a 0.5 n K temperature resolution in the AC technique and the cancellation of the density stratification will enable C(sub V) to be measured down to a reduced temperature of 10(exp -6) with less than a 1% systematic error.

  2. Measuring fluid flow and heat output in seafloor hydrothermal environments

    NASA Astrophysics Data System (ADS)

    Germanovich, Leonid N.; Hurt, Robert S.; Smith, Joshua E.; Genc, Gence; Lowell, Robert P.

    2015-12-01

    We review techniques for measuring fluid flow and advective heat output from seafloor hydrothermal systems and describe new anemometer and turbine flowmeter devices we have designed, built, calibrated, and tested. These devices allow measuring fluid velocity at high- and low-temperature focused and diffuse discharge sites at oceanic spreading centers. The devices perform at ocean floor depths and black smoker temperatures and can be used to measure flow rates ranging over 2 orders of magnitude. Flow velocity is determined from the rotation rate of the rotor blades or paddle assembly. These devices have an open bearing design that eliminates clogging by particles or chemical precipitates as the fluid passes by the rotors. The devices are compact and lightweight enough for deployment from either an occupied or remotely operated submersible. The measured flow rates can be used in conjunction with vent temperature or geochemical measurements to obtain heat outputs or geochemical fluxes from both vent chimneys and diffuse flow regions. The devices have been tested on 30 Alvin dives on the Juan de Fuca Ridge and 3 Jason dives on the East Pacific Rise (EPR). We measured an anomalously low entrainment coefficient (0.064) and report 104 new measurements over a wide range of discharge temperatures (5°-363°C), velocities (2-199 cm/s), and depths (1517-2511 m). These include the first advective heat output measurements at the High Rise vent field and the first direct fluid flow measurement at Middle Valley. Our data suggest that black smoker heat output at the Main Endeavour vent field may have declined since 1994 and that after the 2005-2006 eruption, the high-temperature advective flow at the EPR 9°50'N field may have become more channelized, predominately discharging through the Bio 9 structure. We also report 16 measurements on 10 Alvin dives and 2 Jason dives with flow meters that predate devices described in this work and were used in the process of their development

  3. Adiabatic Heat of Hydration Calorimetric Measurements for Reference Saltstone Waste

    SciTech Connect

    Bollinger, James

    2006-01-12

    The production of nuclear materials for weapons, medical, and space applications from the mid-1950's through the late-1980's at the Savannah River Site (SRS) generated approximately 35 million gallons of liquid high-level radioactive waste, which is currently being processed into vitrified glass for long-term storage. Upstream of the vitrification process, the waste is separated into three components: high activity insoluble sludge, high activity insoluble salt, and very low activity soluble salts. The soluble salt represents 90% of the 35 million gallons of overall waste and is processed at the SRS Saltstone Facility, where it mixed with cement, blast furnace slag, and flyash, creating a grout-like mixture. The resulting grout is pumped into aboveground storage vaults, where it hydrates into concrete monoliths, called saltstone, thus immobilizing the low-level radioactive salt waste. As the saltstone hydrates, it generates heat that slowly diffuses out of the poured material. To ensure acceptable grout properties for disposal and immobilization of the salt waste, the grout temperature must not exceed 95 C during hydration. Adiabatic calorimetric measurements of the heat generated for a representative sample of saltstone were made to determine the time-dependent heat source term. These measurements subsequently were utilized as input to a numerical conjugate heat transfer model to determine the expected peak temperatures for the saltstone vaults.

  4. High temperature thermographic measurements of laser heated silica

    SciTech Connect

    Elhadj, S; Yang, S T; Matthews, M J; Cooke, D J; Bude, J D; Johnson, M; Feit, M; Draggoo, V; Bisson, S E

    2009-11-02

    In situ spatial and temporal surface temperature profiles of CO{sub 2} laser-heated silica were obtained using a long wave infrared (LWIR) HgCdTe camera. Solutions to the linear diffusion equation with volumetric and surface heating are shown to describe the temperature evolution for a range of beam powers, over which the peak surface temperature scales linearly with power. These solutions were used with on-axis steady state and transient experimental temperatures to extract thermal diffusivity and conductivity for a variety of materials, including silica, spinel, sapphire, and lithium fluoride. Experimentally-derived thermal properties agreed well with reported values and, for silica, thermal conductivity and diffusivity are shown to be approximately independent of temperature between 300 and 2800K. While for silica our analysis based on a temperature independent thermal conductivity is shown to be accurate, for other materials studied this treatment yields effective thermal properties that represent reasonable approximations for laser heating. Implementation of a single-wavelength radiation measurement in the semi-transparent regime is generally discussed, and estimates of the apparent temperature deviation from the actual outer surface temperature are also presented. The experimental approach and the simple analysis presented yield surface temperature measurements that can be used to validate more complex physical models, help discriminate dominant heat transport mechanisms, and to predict temperature distribution and evolution during laser-based material processing.

  5. Modeling the relative roles of the foehn wind and urban expansion in the 2002 Beijing heat wave and possible mitigation by high reflective roofs

    NASA Astrophysics Data System (ADS)

    Ma, Hongyun; Shao, Haiyan; Song, Jie

    2014-02-01

    Rapid urbanization has intensified summer heat waves in recent decades in Beijing, China. In this study, effectiveness of applying high-reflectance roofs on mitigating the warming effects caused by urban expansion and foehn wind was simulated for a record-breaking heat wave occurred in Beijing during July 13-15, 2002. Simulation experiments were performed using the Weather Research and Forecast (WRF version 3.0) model coupled with an urban canopy model. The modeled diurnal air temperatures were compared well with station observations in the city and the wind convergence caused by urban heat island (UHI) effect could be simulated clearly. By increasing urban roof albedo, the simulated UHI effect was reduced due to decreased net radiation, and the simulated wind convergence in the urban area was weakened. Using WRF3.0 model, the warming effects caused by urban expansion and foehn wind were quantified separately, and were compared with the cooling effect due to the increased roof albedo. Results illustrated that the foehn warming effect under the northwesterly wind contributed greatly to this heat wave event in Beijing, while contribution from urban expansion accompanied by anthropogenic heating was secondary, and was mostly evident at night. Increasing roof albedo could reduce air temperature both in the day and at night, and could more than offset the urban expansion effect. The combined warming caused by the urban expansion and the foehn wind could be potentially offset with high-reflectance roofs by 58.8 % or cooled by 1.4 °C in the early afternoon on July 14, 2002, the hottest day during the heat wave.

  6. Remote Sensing of the Urban Heat Island Effect: Assessment of Risks to Human Health and Development of Mitigation Strategies for Sustainable Cities

    NASA Technical Reports Server (NTRS)

    Quattrochi, Dale A.; Luvall, Jeffrey C.; Rickman, Douglas L.; Estes, Maurice G., Jr.; Laymon, Charles A.; Crosson, William; Howell, Burgess F.; Gillani, Noor V.; Arnold, James E. (Technical Monitor)

    2001-01-01

    The growth of cities, both in population and in areal extent, appears as an inexorable process. Urbanization continues at a rapid rate, and it is estimated that by the year 2025, 80% of the world's population will live in cities. One of the more egregious side effects of urbanization is the deterioration in air quality as a result of increased vehicular traffic, industrialization and related activities. In the United States alone, under the more stringent air quality guidelines established by the U.S. Environmental Protection Agency (EPA) in 1997, nearly 300 counties in 34 states will not meet the new air quality standards for ground level ozone. The mitigation of one the physical/environmental characteristics of urbanization known as the urban heat island (UHI) effect, is now being looked at more closely as a possible way to bring down ground level ozone levels in cities and assist states in improving air quality. The UHI results from the replacement of "natural" land covers (e.g., trees, grass) with urban land surface types, such as pavement and buildings. Heat stored in these surfaces is released into the air and results in a "dome" of elevated air temperatures that presides over cities. The effect of this dome of elevated air temperatures is known as the UHI, which is most prevalent about 2-3 hours after sunset on days with intense solar radiation and calm winds. Given the local and regional impacts of the UHI, there are significant potential affects on human health, particularly as related to heat stress and ozone on body temperature regulation and on the cardiovascular and respiratory systems. In this study we are using airborne and satellite remote sensing data to analyze how differences in the urban landscape influence or drive the development of the UHI over four U.S. cities. Additionally, we are assessing what the potential impact is on risks to human health, and developing mitigation strategies to make urban areas more environmentally sustainable.

  7. High Spatial Resolution Thermal Remote Sensing of the Urban Heat Island Effect: Assessment of Risks to Human Health and Development of Mitigation Strategies for Sustainable Cities

    NASA Technical Reports Server (NTRS)

    Quattrochi, Dale A.; Luvall, Jeffrey C.; Rickman, Douglas L.; Estes, Maurice G., Jr.; Laymon, Charles A.; Crosson, William; Howell, Burgess F.; Gillani, Noor V.; Arnold, James E. (Technical Monitor)

    2002-01-01

    The growth of cities, both in population and in areal extent, appears as an inexorable process. Urbanization continues at a rapid rate, and it is estimated that by the year 2025, 80% of the world's population will live in cities. One of the more egregious side effects of urbanization is the deterioration in air quality as a result of increased vehicular traffic, industrialization and related activities. In the United States alone, under the more stringent air quality guidelines established by the U.S. Environmental Protection Agency (EPA) in 1997, nearly 300 counties in 34 states will not meet the new air quality standards for ground level ozone. The mitigation of one the physical/environmental characteristics of urbanization known as the urban heat island (UHI) effect, is now being looked at more closely as a possible way to bring down ground level ozone levels in cities and assist states in improving air quality. The UHI results from the replacement of "natural" land covers (e.g., trees, grass) with urban land surface types, such as pavement and buildings. Heat stored in these surfaces is released into the air and results in a "dome" of elevated air temperatures that presides over cities. The effect of this dome of elevated air temperatures is known as the UHI, which is most prevalent about 2-3 hours after sunset on days with intense solar radiation and calm winds. Given the local and regional impacts of the UHI, there are significant potential affects on human health, particularly as related to heat stress and ozone on body temperature regulation and on the cardiovascular and respiratory systems. In this study we are using airborne and satellite remote sensing data to analyze how differences in the urban landscape influence or drive the development of the UHI over four U.S. cities. Additionally, we are assessing what the potential impact is on risks to human health, and developing mitigation strategies to make urban areas more environmentally sustainable.

  8. Infrared Low Temperature Turbine Vane Rough Surface Heat Transfer Measurements

    NASA Technical Reports Server (NTRS)

    Boyle, R. J.; Spuckler, C. M.; Lucci, B. L.; Camperchioli, W. P.

    2000-01-01

    Turbine vane heat transfer distributions obtained using an infrared camera technique are described. Infrared thermography was used because noncontact surface temperature measurements were desired. Surface temperatures were 80 C or less. Tests were conducted in a three vane linear cascade, with inlet pressures between 0.14 and 1.02 atm., and exit Mach numbers of 0.3, 0.7, and 0.9, for turbulence intensities of approximately 1 and 10%. Measurements were taken on the vane suction side, and on the pressure side leading edge region. The designs for both the vane and test facility are discussed. The approach used to account for conduction within the vane is described. Midspan heat transfer distributions are given for the range of test conditions.

  9. Global surface temperature/heat transfer measurements using infrared imaging

    NASA Technical Reports Server (NTRS)

    Daryabeigi, Kamran

    1992-01-01

    A series of studies were conducted to evaluate the use of scanning radiometric infrared imaging systems for providing global surface temperature/heat transfer measurements in support of hypersonic wind tunnel testing. The in situ precision of the technique with narrow temperature span setting over the temperature range of 20 to 200 C was investigated. The precision of the technique over wider temperature span settings was also determined. The accuracy of technique for providing aerodynamic heating rates was investigated by performing measurements on a 10.2-centimeter hemisphere model in the Langley 31-inch Mach 10 tunnel, and comparing the results with theoretical predictions. Data from tests conducted on a generic orbiter model in this tunnel are also presented.

  10. Heat of reaction measurements for hydrothermal carbonization of biomass.

    PubMed

    Funke, Axel; Ziegler, Felix

    2011-08-01

    This paper presents a set of calorimetric measurements with the aim of better understanding the calorific nature of hydrothermal carbonization. Presented values so far show an inadequately high scatter to do so, preventing a well funded assessment of the energetic feasibility of this process. The heat released during hydrothermal carbonization at 240°C measured with the applied differential calorimetry setup is -1.06MJ/kg(glucose,daf) with a standard deviation of 14%, -1.07MJ/kg(cellulose,daf) with a standard deviation of 9%, and -0.76MJ/kg(wood,daf) with a standard deviation of 32%. These results are in good agreement with the theoretically derived maximum heat release. Despite the comparably high experimental standard deviation of these results, their accuracy is considerably higher than previously published results.

  11. Preliminary measurements on heat balance in pneumatic tires

    NASA Technical Reports Server (NTRS)

    Nybakken, G. H.; Collart, D. Y.; Staples, R. J.; Lackey, J. I.; Clark, S. K.; Dodge, R. N.

    1973-01-01

    A variety of tests was undertaken to determine the nature of heat generation associated with a pneumatic tire operating under various conditions. Tests were conducted to determine the magnitude and distribution of internally generated heat caused by hysteresis in the rubber and ply fabric in an automobile tire operating under conditions of load, pressure, and velocity representative of normal operating conditions. These included tests at various yaw angles and tests with braking applied. In other tests, temperature sensors were mounted on a road to measure the effect of a tire rolling over and an attempt was made to deduce the magnitude and nature of interfacial friction from the resulting information. In addition, tests were performed using the scratch plate technique to determine the nature of the motion between the tire and road. Finally, a model tire was tested on a roadwheel, the surface covering which could be changed, and an optical pyrometer was used to measure rubber surface temperatures.

  12. Laser-heated X-ray flashlamp brightness measurements

    SciTech Connect

    Matthews, D.L.; Campbell, E.M.; Hagelstein, P.; Halsey, W.; Kauffman, R.L.; Koppel, L.; Phillion, D.; Price, R.; Toor, A.

    1983-12-01

    The authors present measurements of the X-ray emission characteristics of laser-irradiated flashlamp foils which are candidates to produce by resonant photoexcitation a population inversion in either a neon or fluorine lasant gas. Using the Shiva 1.06 ..mu.. laser, the authors heated Fe, Cr, and Ni foils to study the brightness and centroid energies of X-ray lines stemming from L-M transitions. Results indicate that appropriately bright and uniform sources can be produced.

  13. Mitigation measures to contain the environmental impact of urban areas: a bibliographic review moving from the life cycle approach.

    PubMed

    Belussi, Lorenzo; Barozzi, Benedetta

    2015-12-01

    The global environmental impact of urban areas has greatly increased over the years, due to the growth of urbanisation and the associated increase in management costs. There are several measures aimed at mitigating this impact that affect in different ways the environmental, economic and societal spheres. This article has analysed a selection of different mitigation measures, related to the built environment, according to the life cycle approach, aimed at identifying the procedural features chosen by the different authors and defining a common way to deal with this issue. In particular, all the individual single steps of a Life Cycle Assessment/Life Cycle Costing of the different studies are analysed and the results of the individual measures are highlighted. The analysis has shown how the scientific literature is mainly focused on the evaluation of the impact of technological solutions related to individual buildings (cool/green roof). Less interest is shown in the solutions for urban areas, while, as far as the impact on greenhouse gas emissions is concerned, some studies are shifting the target to a global scale. Due to the accuracy whereby the calculation of the impact indicators deals with and structures the life cycle methods, opportunities to compare studies developed by different authors are quite rare and hard to find. Hence the need to find a simple, intuitive and flexible scheme to combine some of the most useful results of the bibliographical studies, in a comparative outline of different technological solutions, which can support the decision-making phase through a rough assessment.

  14. Investigation of radon entry and effectiveness of mitigation measures in seven houses in New Jersey: Midproject report

    SciTech Connect

    Matthews, T.G.; Dudney, C.S.; Monar, K.P.; Landguth, D.C.; Wilson, D.L.; Hawthorne, A.R.; Hubbard, L.M.; Gadsby, K.J.; Bohac, D.L.; Decker, C.A.

    1987-12-01

    A detailed radon mitigation study is in progress in 14 homes in the New Jersey Piedmont area. The principal goals are the refinement of diagnostic measurements for selection and implementation of mitigation systems, and the reduction of radon concentrations to acceptable levels inside the study houses. Monitoring stations were installed in each home in October, 1986. Instrumented measurements included: basement and upstairs radon; differential pressures across the basement/subslag, basement/upstairs and basement/outdoor interfaces; temperatures at basement, upstairs and outdoor locations; and central air handler usage. A weather station was located at one house, monitoring wind speed and direction; barometric pressure; precipitation; soil temperature; and outdoor temperature and relative humidity. A time-averaged value of all of the above parameters was recorded every 30 min. Several additional parameters were monitored on an intermittent basis in all or selected homes. These include multizone air infiltration rates which have been measured in all homes using passive perfluorocarbon tracers (PFT) and in two homes using a constant concentration tracer gas system (CCTG). Total radon progeny, soil gas radon concentration and permeability characteristics, and gamma radiation levels were also monitored periodically in all study homes. 10 refs., 53 figs.

  15. Distributed Sensible Heat Flux Measurements for Wireless Sensor Networks

    NASA Astrophysics Data System (ADS)

    Huwald, H.; Brauchli, T.; Lehning, M.; Higgins, C. W.

    2015-12-01

    The sensible heat flux component of the surface energy balance is typically computed using eddy covariance or two point profile measurements while alternative approaches such as the flux variance method based on convective scaling has been much less explored and applied. Flux variance (FV) certainly has a few limitations and constraints but may be an interesting and competitive method in low-cost and power limited wireless sensor networks (WSN) with the advantage of providing spatio-temporal sensible heat flux over the domain of the network. In a first step, parameters such as sampling frequency, sensor response time, and averaging interval are investigated. Then we explore the applicability and the potential of the FV method for use in WSN in a field experiment. Low-cost sensor systems are tested and compared against reference instruments (3D sonic anemometers) to evaluate the performance and limitations of the sensors as well as the method with respect to the standard calculations. Comparison experiments were carried out at several sites to gauge the flux measurements over different surface types (gravel, grass, water) from the low-cost systems. This study should also serve as an example of spatially distributed sensible heat flux measurements.

  16. Construction and measurements of a vacuum-swing-adsorption radon-mitigation system

    SciTech Connect

    Schnee, R. W.; Bunker, R.; Ghulam, G.; Jardin, D.; Kos, M.; Tenney, A. S.

    2013-08-08

    Long-lived alpha and beta emitters in the {sup 222}Rn decay chain on (and near) detector surfaces may be the limiting background in many experiments attempting to detect dark matter or neutrinoless double beta decay, and in screening detectors. In order to reduce backgrounds from radon-daughter plate-out onto the wires of the Beta Cage during its assembly, an ultra-low-radon cleanroom is being commissioned at Syracuse University using a vacuum-swing-adsorption radon-mitigation system. The radon filter shows ∼20× reduction at its output, from 7.47±0.56 to 0.37±0.12 Bq/m{sup 3}, and the cleanroom radon activity meets project requirements, with a lowest achieved value consistent with that of the filter, and levels consistently < 2 Bq/m{sup 3}.

  17. Measurement of the SOC State Specific Heat in 4He

    NASA Astrophysics Data System (ADS)

    Chatto, A. R.; Lee, R. A. M.; Duncan, R. V.; Day, P. K.; Goodstein, D. L.

    2006-09-01

    When a heat flux Q is applied downward through a sample of liquid 4He near the lambda transition, the helium self organizes such that the gradient in temperature matches the gravity induced gradient in Tλ. All the helium in the sample is then at the same reduced temperature tSOC = TSOC-Tλ/Tλ and the helium is said to be in the Self-Organized Critical (SOC) state. We have made preliminary measurements of the 4He SOC state specific heat, C∇T(T(Q)). Despite having a cell height of 2.54 cm, our results show no difference between C∇T and the zero-gravity 4He specific heat results of the Lambda Point Experiment (LPE) [J.A. Lipa et al., Phys. Rev. B, 68, 174518 (2003)] over the range 250 to 450 nK below the transition. There is no gravity rounding because the entire sample is at the same reduced temperature tSOC(Q). Closer to Tλ the SOC specific heat falls slightly below LPE, reaching a maximum at approximately 50 nK below Tλ, in agreement with theoretical predictions [R. Haussmann, Phys. Rev. B, 60, 12349 (1999)].

  18. Heat Transfer Measurements for a Film Cooled Turbine Vane Cascade

    NASA Technical Reports Server (NTRS)

    Poinsatte, Philip E.; Heidmann, James D.; Thurman, Douglas R.

    2008-01-01

    Experimental heat transfer and pressure measurements were obtained on a large scale film cooled turbine vane cascade. The objective was to investigate heat transfer on a commercial high pressure first stage turbine vane at near engine Mach and Reynolds number conditions. Additionally blowing ratios and coolant density were also matched. Numerical computations were made with the Glenn-HT code of the same geometry and compared with the experimental results. A transient thermochromic liquid crystal technique was used to obtain steady state heat transfer data on the mid-span geometry of an instrumented vane with 12 rows of circular and shaped film cooling holes. A mixture of SF6 and Argon gases was used for film coolant to match the coolant-to-gas density ratio of a real engine. The exit Mach number and Reynolds number were 0.725 and 2.7 million respectively. Trends from the experimental heat transfer data matched well with the computational prediction, particularly for the film cooled case.

  19. Soil heat flux measurements in an open forest

    NASA Astrophysics Data System (ADS)

    van der Meulen, M. W. J.; Klaassen, W.

    1996-05-01

    The soil surface heat flux in an open oak forest was determined at four locations to account for the heterogeneity of the forest. Soil temperatures and soil water content were measured at several depths and an integration method with three layers was used. The thickness of the bottom layer was determined with a spectral method. The soil surface heat flux was compared with the net radiation above the canopy for four typical days in 1995. These data were fitted linearly. The slope of this parameterisation was 0.092, with a leaf area index of 2.5 (fully-leafed canopy). This result was compared with four other studies. To produce an exponential fit of the slope against the leaf area index the Beer-Bouguer law for radiation extinction in canopies and a soil surface heat flux proportional to the net radiation at the forest floor was used. An extinction coefficient of 0.36 was found. This result is recommended for future studies, if soil surface heat flux is requested and net radiation data above the canopy as well as leaf area index are available.

  20. Recovery Temperature, Transition, and Heat Transfer Measurements at Mach 5

    NASA Technical Reports Server (NTRS)

    Brinich, Paul F.

    1961-01-01

    Schlieren, recovery temperature, and heat-transfer measurements were made on a hollow cylinder and a cone with axes alined parallel to the stream. Both the cone and cylinder were equipped with various bluntnesses, and the tests covered a Reynolds number range up to 20 x 10(exp 6) at a free-stream Mach number of 4.95 and wall to free-stream temperature ratios from 1.8 to 5.2 (adiabatic). A substantial transition delay due to bluntness was found for both the cylinder and the cone. For the present tests (Mach 4.95), transition was delayed by a factor of 3 on the cylinder and about 2 on the cone, these delays being somewhat larger than those observed in earlier tests at Mach 3.1. Heat-transfer tests on the cylinder showed only slight effects of wall temperature level on transition location; this is to be contrasted to the large transition delays observed on conical-type bodies at low surface temperatures at Mach 3.1. The schlieren and the peak-recovery-temperature methods of detecting transition were compared with the heat-transfer results. The comparison showed that the first two methods identified a transition point which occurred just beyond the end of the laminar run as seen in the heat-transfer data.

  1. Economic aspects of hydro geological risk mitigation measures management in Italy: the ReNDiS project experience

    NASA Astrophysics Data System (ADS)

    Spizzichino, D.; Campobasso, C.; Gallozzi, P. L.; Dessi', B.; Traversa, F.

    2009-04-01

    ReNDiS project is a useful tool for monitoring, analysis and management of information data on mitigation measures and restoration works of soil protection at national scale. The main scope of the project, and related monitoring activities, is to improve the knowledge about the use of national funds and efforts against floods and landslides risk and, as a consequence, to better address the preventive policies in future. Since 1999 after the disastrous mudflow event occurred in Sarno in 1998, which caused the loss of 160 human lives, an extraordinary effort was conducted by the Italian Government in order to promote preventive measures against the hydro geological risk over the entire Italian territory. The Italian Ministry for the Environment promoted several and annual soil protection programmes. The ReNDiS project (Repertory of mitigation measures for National Soil Protection) is carried out by ISPRA - Institute for Environmental protection and Research, with the aim of improving the knowledge about the results of preventive policies against floods and landslides in order to better address national funds as requested by the Minister itself. The repertory is composed by a main archive and two secondary interface, the first for direct data management (ReNDiS-ist) and the latter (ReNDiS-web) for the on-line access and public consultation. At present, ReNDiS database contains about 3000 records concerning those programmes, focused on restoration works but including also information on landslide typologies and processes. The monitoring project is developed taking into account all the information about each step of every mitigation measure from the initial funding phase until the end of the work. During present work, we have statistically analyzed the ReNDiS database in order to highlight the conformity between the characteristic and type of the hazard (identified in a specific area) and the corresponding mitigation measures adopted for risk reduction. Through specific

  2. In vivo measurement of swine endocardial convective heat transfer coefficient.

    PubMed

    Tangwongsan, Chanchana; Will, James A; Webster, John G; Meredith, Kenneth L; Mahvi, David M

    2004-08-01

    We measured the endocardial convective heat transfer coefficient h at 22 locations in the cardiac chambers of 15 pigs in vivo. A thin-film Pt catheter tip sensor in a Wheatstone-bridge circuit, similar to a hot wire/film anemometer, measured h. Using fluoroscopy, we could precisely locate the steerable catheter sensor tip and sensor orientation in pigs' cardiac chambers. With flows, h varies from 2500 to 9500 W/m2 x K. With zero flow, h is approximately 2400 W/m2 x K. These values of h can be used for the finite element method modeling of radiofrequency cardiac catheter ablation.

  3. Simulation of Urban Heat Island Mitigation Strategies in Atlanta, GA Using High-Resolution Land Use/Land Cover Data Set to Enhance Meteorological Modeling

    NASA Technical Reports Server (NTRS)

    Crosson, William L.; Dembek, Scott; Estes, Maurice G., Jr.; Limaye, Ashutosh S.; Lapenta, William; Quattrochi, Dale A.; Johnson, Hoyt; Khan, Maudood

    2006-01-01

    The specification of land use/land cover (LULC) and associated land surface parameters in meteorological models at all scales has a major influence on modeled surface energy fluxes and boundary layer states. In urban areas, accurate representation of the land surface may be even more important than in undeveloped regions due to the large heterogeneity within the urban area. Deficiencies in the characterization of the land surface related to the spatial or temporal resolution of the data, the number of LULC classes defined, the accuracy with which they are defined, or the degree of heterogeneity of the land surface properties within each class may degrade the performance of the models. In this study, an experiment was conducted to test a new high-resolution LULC data set for meteorological simulations for the Atlanta, Georgia metropolitan area using a mesoscale meteorological model and to evaluate the effects of urban heat island (UHI) mitigation strategies on modeled meteorology for 2030. Simulation results showed that use of the new LULC data set reduced a major deficiency of the land use data used previously, specifically the poor representation of urban and suburban land use. Performance of the meteorological model improved substantially, with the overall daytime cold bias reduced by over 30%. UHI mitigation strategies were projected to offset much of a predicted urban warming between 2000 and 2030. In fact, for the urban core, the cooling due to UHI mitigation strategies was slightly greater than the warming associated with urbanization over this period. For the larger metropolitan area, cooling only partially offset the projected warming trend.

  4. Current status of decay heat measurements, evaluations, and needs

    SciTech Connect

    Dickens, J.K.

    1986-07-01

    Over a decade ago serious concern over possible consequences of a loss-of-coolant accident in a commercial light-water reactor prompted support of several experiments designed specifically to measure the latent energy of beta-ray and gamma-ray emanations from fission products for thermal reactors. This latent energy was termed Decay Heat. At about the same time the American Nuclear Society convened a working group to develop a standard for use in computing decay heat in real reactor environs primarily for regulatory requirements. This working group combined the new experimental results and best evaluated data into a standard which was approved by the ANS and by the ANSI. The primary work since then has been: (a) on improvements to computational efforts and (b) experimental measurements for fast reactors. In addition, the need for decay-heat data has been extended well beyond the time regime of a loss-of-coolant accident; new concerns involve, for example, away-from-reactor shipments and storage. The efficacy of the ANS standard for these longer time regimes has been a subject of study with generally positive results. However, a specific problem, namely, the consequences of fission-product neutron capture, remains contentious. Satisfactory resolution of this problem merits a high priority. 31 refs., 4 figs., 1 tab.

  5. Local Heat Flux Measurements with Single Element Coaxial Injectors

    NASA Technical Reports Server (NTRS)

    Jones, Gregg; Protz, Christopher; Bullard, Brad; Hulka, James

    2006-01-01

    To support the mission for the NASA Vision for Space Exploration, the NASA Marshall Space Flight Center conducted a program in 2005 to improve the capability to predict local thermal compatibility and heat transfer in liquid propellant rocket engine combustion devices. The ultimate objective was to predict and hence reduce the local peak heat flux due to injector design, resulting in a significant improvement in overall engine reliability and durability. Such analyses are applicable to combustion devices in booster, upper stage, and in-space engines, as well as for small thrusters with few elements in the injector. In this program, single element and three-element injectors were hot-fire tested with liquid oxygen and ambient temperature gaseous hydrogen propellants at The Pennsylvania State University Cryogenic Combustor Laboratory from May to August 2005. Local heat fluxes were measured in a 1-inch internal diameter heat sink combustion chamber using Medtherm coaxial thermocouples and Gardon heat flux gauges. Injectors were tested with shear coaxial and swirl coaxial elements, including recessed, flush and scarfed oxidizer post configurations, and concentric and non-concentric fuel annuli. This paper includes general descriptions of the experimental hardware, instrumentation, and results of the hot-fire testing for three of the single element injectors - recessed-post shear coaxial with concentric fuel, flush-post swirl coaxial with concentric fuel, and scarfed-post swirl coaxial with concentric fuel. Detailed geometry and test results will be published elsewhere to provide well-defined data sets for injector development and model validatation.

  6. Heat conduction nanocalorimeter for pl-scale single cell measurements

    NASA Astrophysics Data System (ADS)

    Johannessen, E. A.; Weaver, J. M. R.; Cobbold, P. H.; Cooper, J. M.

    2002-03-01

    An ultrasensitive nanocalorimeter for use with pl-scale biological samples using silicon microfabrication technology has been developed in which a 720 pl reaction vessel, a calibration heater, and a thermoelectric transducer of 125 μK sensitivity were integrated into a single multilayer thin-film configuration. The resolution of the system ranged from 10 to 25 nW depending on the heat capacity, conductance and power density of the samples studied. The device has been used in heat conduction measurements of the energy released from the enzyme catalyzed hydrolysis of hydrogen peroxide using purified catalase, and for the determination of the catalase activity within a single mouse hepatocyte. The nanocalorimeter has the potential for integration in a high-density array format, where the change in temperature from ultralow volume cellular assays could be used as a generic analytical tool for high throughput screening of bioactive compounds.

  7. CARS Temperature Measurements in a Combustion-Heated Supersonic Jet

    NASA Technical Reports Server (NTRS)

    Tedder, S. A.; Danehy, P. M.; Magnotti, G.; Cutler, A. D.

    2009-01-01

    Measurements were made in a combustion-heated supersonic axi-symmetric free jet from a nozzle with a diameter of 6.35 cm using dual-pump Coherent Anti-Stokes Raman Spectroscopy (CARS). The resulting mean and standard deviation temperature maps are presented. The temperature results show that the gas temperature on the centerline remains constant for approximately 5 nozzle diameters. As the heated gas mixes with the ambient air further downstream the mean temperature decreases. The standard deviation map shows evidence of the increase of turbulence in the shear layer as the jet proceeds downstream and mixes with the ambient air. The challenges of collecting data in a harsh environment are discussed along with influences to the data. The yield of the data collected is presented and possible improvements to the yield is presented are discussed.

  8. CO{sub 2}-mitigation measures through reduction of fossil fuel burning in power utilities. Which road to go?

    SciTech Connect

    Kaupp, A.

    1996-12-31

    Five conditions, at minimum, should be examined in the comparative analysis of CO{sub 2}-mitigation options for the power sector. Under the continuing constraint of scarce financial resources for any private or public investment in the power sector, the following combination of requirements characterise a successful CO{sub 2}-mitigation project: (1) Financial attractiveness for private or public investors. (2) Low, or even negative, long range marginal costs per ton of `CO{sub 2} saved`. (3) High impact on CO{sub 2}-mitigation, which indicates a large market potential for the measure. (4) The number of individual investments required to achieve the impact is relatively small. In other words, logistical difficulties in project implementation are minimised. (5) The projects are `socially fair` and have minimal negative impact on any segment of the society. This paper deals with options to reduce carbonaceous fuel burning in the power sector. Part I explains how projects should be selected and classified. Part II describes the technical options. Since reduction of carbonaceous fuel burning may be achieved through Demand Side Management (DSM) and Supply Side Management (SSM) both are treated. Within the context of this paper SSM does not mean to expand power supply as demand grows. It means to economically generate and distribute power as efficiently as possible. In too many instances DSM has degenerated into efficient lighting programs and utility managed incentives and rebate programs. To what extent this is a desirable situation for utilities in Developing Countries that face totally different problems as their counterparts in highly industrialised countries remains to be seen. Which road to go is the topic of this paper.

  9. Heat generation rate measurement in a Li-ion cell at large C-rates through temperature and heat flux measurements

    NASA Astrophysics Data System (ADS)

    Drake, S. J.; Martin, M.; Wetz, D. A.; Ostanek, J. K.; Miller, S. P.; Heinzel, J. M.; Jain, A.

    2015-07-01

    Understanding the rate of heat generation in a Li-ion cell is critical for safety and performance of Li-ion cells and systems. Cell performance, cycle life, and system safety all depend on temperature distribution in the cell, which, in turn, depends on heat generation rate within the cell and on heat removal rate at the cell surface. Despite the existence of a number of theoretical models to predict heat generation rate, there is not much literature on experimental measurement at high C-rates. This paper reports measurement of heat generation rate from a Li-ion cell at high discharge rates, up to 9.6C, using measurements of cell temperature and surface heat flux. As opposed to calorimetry-based approaches, this method can be applied in situ to yield measurements of heat generation rate in laboratory or field use provided that at least one a priori test is performed to measure the temperature gradient within a cell in the same ambient condition. This method is based on simultaneous determination of heat stored and heat lost from the cell through heat flux and temperature measurements. A novel method is established for measurement of the internal temperature of the cell. Heat generation measurements are shown to agree with well-established theoretical models. The effect of actively cooling the cell is briefly discussed.

  10. Measuring and mitigating agricultural greenhouse gas production in the US Great Plains, 1870-2000.

    PubMed

    Parton, William J; Gutmann, Myron P; Merchant, Emily R; Hartman, Melannie D; Adler, Paul R; McNeal, Frederick M; Lutz, Susan M

    2015-08-25

    The Great Plains region of the United States is an agricultural production center for the global market and, as such, an important source of greenhouse gas (GHG) emissions. This article uses historical agricultural census data and ecosystem models to estimate the magnitude of annual GHG fluxes from all agricultural sources (e.g., cropping, livestock raising, irrigation, fertilizer production, tractor use) in the Great Plains from 1870 to 2000. Here, we show that carbon (C) released during the plow-out of native grasslands was the largest source of GHG emissions before 1930, whereas livestock production, direct energy use, and soil nitrous oxide emissions are currently the largest sources. Climatic factors mediate these emissions, with cool and wet weather promoting C sequestration and hot and dry weather increasing GHG release. This analysis demonstrates the long-term ecosystem consequences of both historical and current agricultural activities, but also indicates that adoption of available alternative management practices could substantially mitigate agricultural GHG fluxes, ranging from a 34% reduction with a 25% adoption rate to as much as complete elimination with possible net sequestration of C when a greater proportion of farmers adopt new agricultural practices.

  11. Measuring and mitigating agricultural greenhouse gas production in the US Great Plains, 1870–2000

    PubMed Central

    Parton, William J.; Gutmann, Myron P.; Merchant, Emily R.; Hartman, Melannie D.; Adler, Paul R.; McNeal, Frederick M.; Lutz, Susan M.

    2015-01-01

    The Great Plains region of the United States is an agricultural production center for the global market and, as such, an important source of greenhouse gas (GHG) emissions. This article uses historical agricultural census data and ecosystem models to estimate the magnitude of annual GHG fluxes from all agricultural sources (e.g., cropping, livestock raising, irrigation, fertilizer production, tractor use) in the Great Plains from 1870 to 2000. Here, we show that carbon (C) released during the plow-out of native grasslands was the largest source of GHG emissions before 1930, whereas livestock production, direct energy use, and soil nitrous oxide emissions are currently the largest sources. Climatic factors mediate these emissions, with cool and wet weather promoting C sequestration and hot and dry weather increasing GHG release. This analysis demonstrates the long-term ecosystem consequences of both historical and current agricultural activities, but also indicates that adoption of available alternative management practices could substantially mitigate agricultural GHG fluxes, ranging from a 34% reduction with a 25% adoption rate to as much as complete elimination with possible net sequestration of C when a greater proportion of farmers adopt new agricultural practices. PMID:26240366

  12. Zebra mussel mitigation; overview

    SciTech Connect

    Claudi, R.

    1995-06-01

    Zebra mussels cause a number of problems to industrial raw water users as well as having serious impact on civil structures exposed to mussel infested waters. The largest volume of water (up to 90% of the total) drawn into most industrial and power generating plants, is for cooling and heat transfer. The rest of the volume is used for other plant processes, such as make-up in steam systems, and service systems used for cleaning, air conditions, fire protection and human consumption. All raw water systems are vulnerable to zebra mussel infestation to greater or lesser degree. To-date, many different chemical and non-chemical techniques for zebra mussel control have been investigated. However, the treatment of choice for most facilities is based on chemical control. This has been the common practice in Europe and so far it has been the case in North America. This is likely to change as the environmental constraints on release of chemicals into natural water bodies continue to increase. This paper deals with the different steps raw water users should take when deciding on a mitigation strategy, the mitigation measures available to-date and those that have been proposed for the control of zebra mussels in industrial systems.

  13. Assessing the effect of nutrient mitigation measures in the watersheds of the Southern Bight of the North Sea.

    PubMed

    Thieu, Vincent; Garnier, Josette; Billen, Gilles

    2010-02-15

    The Seine, Somme, and Scheldt Rivers (France, Belgium, and Netherlands) are the major delivering rivers flowing into the continental coastal zone of the Southern Bight of the North Sea, an area regularly affected by eutrophication problems. In the present work, the Seneque-Riverstrahler model was implemented in a multi-regional case study in order to test several planned mitigation measures aimed at limiting stream nutrient contamination and restoring balanced nutrient ratios at the coastal zone. This modeling approach, which is spatially distributed at the basin scale, allows assessing the impact of any change in human activities, which widely differ over the three basins. Here, we define realistic scenarios based on currently proposed measures to reduce point and non-point sources, such as the upgrading of wastewater treatment, the introduction of catch crops, and the development of extensive farming. An analysis of the current situation showed that a 47-72% reduction in P point-source emissions within the three basins could be reached if the intended P treatment was generalized to the largest treatment plants. However, only an overall 14-23% reduction in N could be achieved at the outlet of the three basins, by combining improved wastewater treatment and land use with management measures aimed at regulating agricultural practices. Nonetheless, in spite of these efforts, N will still be exported in large excess with respect to the equilibrium defined by the Redfield ratios, even in the most optimistic hypothesis describing the long-term response of groundwater nitrate concentrations. A comprehensive assessment of these mitigation measures supports the need for additional reductions of nutrient losses from agriculture to control harmful algae development. It also stresses the relevance of this mechanistic approach, in which nutrient transfers from land to sea can be calculated, as an integrated strategy to test policy recommendations.

  14. How to mitigate impacts of wind farms on bats? A review of potential conservation measures in the European context

    SciTech Connect

    Peste, Filipa; Paula, Anabela; Silva, Luís P. da; Bernardino, Joana; Pereira, Pedro; Mascarenhas, Miguel; Costa, Hugo; Vieira, José; Bastos, Carlos; Pereira, Maria João Ramos

    2015-02-15

    Wind energy is growing worldwide as a source of power generation. Bat assemblages may be negatively affected by wind farms due to the fatality of a significant number of individuals after colliding with the moving turbines or experiencing barotrauma. The implementation of wind farms should follow standard procedures to prevent such negative impacts: avoid, reduce and offset, in what is known as the mitigation hierarchy. According to this approach avoiding impacts is the priority, followed by the minimisation of the identified impacts, and finally, when residual negative impacts still remain, those must be offset or at least compensated. This paper presents a review on conservation measures for bats and presents some guidelines within the compensation scenario, focusing on negative impacts that remain after avoidance and minimisation measures. The conservation strategies presented aim at the improvement of the ecological conditions for the bat assemblage as a whole. While developed under the European context, the proposed measures are potentially applicable elsewhere, taking into consideration the specificity of each region in terms of bat assemblages present, landscape features and policy context regarding nature and biodiversity conservation and management. An analysis of potential opportunities and constraints arising from the implementation of offset/compensation programmes and gaps in the current knowledge is also considered. - Highlights: • Wind energy impacts bat populations in ways not yet fully understood. • As the use of windfarms is growing worldwide greater impacts on bat populations are also expected. • Mitigation hierarchy provides a way to reduce impacts from new wind farm facilities. • Compensation measures may be used to reduce the residual effects on bat populations. • Identify bats ecological needs and compensate according to the existing surroundings.

  15. Evaluation of the varying Naturally Occurring Asbestos mitigation measures at School and Commercial construction projects in California

    NASA Astrophysics Data System (ADS)

    Kalika, S.

    2012-12-01

    In commercial development or K-12 school construction, project sites are often purchased and much of the planning process completed prior to an assessment of the soils proposed for excavation or potential offhaul. Geologic maps, while initially helpful for identifying potential hazards such as landslides and earthquake faults, are less helpful in the identification of naturally occurring hazardous minerals, such as the seven regulated minerals currently classified as asbestos. Geologic maps identify mafic and ultramafic bedrock zones; however, a skilled geologist with knowledge of asbestos hazards will further visualize the earth-shaping processes that may have resulted in the deposition of naturally occurring asbestos in locations outside mapped ultramafic zones including the base of an alluvial fan or within streambed channels. When sampled as an afterthought prior to disposal, property owners are surprised by the budget-crippling costs of waste handling and disposal of NOA, as well as mitigations required to protect the health of construction workers, the public, and future site occupants. The California Air Resources Board (CARB) continues to lead the way in evaluation and regulation of NOA, through development of the CARB 435 preparation and laboratory analytical method, local enforcement of the Asbestos Airborne Toxic Control Measure for Construction, Grading, Quarrying, and Surface Mining Operations (ATCM), and implementation of dust control measures to protect public health. A thorough site evaluation and construction design includes utilization of the sampling methods developed by the California Geological Survey, laboratory analytical methods within CARB 435, and mitigation measures required by CARB, DTSC, and OSHA for the protection of worker and public health after NOA is discovered. The site evaluation should additionally include an assessment of the future site usage, as regulations differ based on potential health affects to future occupants

  16. The biophysical and physiological basis for mitigated elevations in heart rate with electric fan use in extreme heat and humidity

    NASA Astrophysics Data System (ADS)

    Ravanelli, Nicholas M.; Gagnon, Daniel; Hodder, Simon G.; Havenith, George; Jay, Ollie

    2016-07-01

    Electric fan use in extreme heat wave conditions has been thought to be disadvantageous because it might accelerate heat gain to the body via convection. However, it has been recently shown that fan use delays increases in heart rate even at high temperatures (42 °C) in young adults. We here assess the biophysical and physiological mechanisms underlying the apparently beneficial effects of fan use. Eight males (24 ± 3 y; 80.7 ± 11.7 kg; 2.0 ± 0.1 m2) rested at either 36 °C or 42 °C, with (F) or without (NF) electric fan use (4.2 m/s) for 120 min while humidity increased every 7.5 min by 0.3 kPa from a baseline value of 1.6 kPa. Heart rate (HR), local sweat rate (LSR), cutaneous vascular conductance (CVC), core and mean skin temperatures, and the combined convective/radiative heat loss (C+R), evaporative heat balance requirements (Ereq) and maximum evaporative potential (Emax) were assessed. C+R was greater with fan use at 36 °C (F 8 ± 6, NF 2 ± 2 W/m2; P = 0.04) and more negative (greater dry heat gain) with fan use at 42 °C (F -78 ± 4, NF -27 ± 2 W/m2; P < 0.01). Consequently, Ereq was lower at 36 °C (F 38 ± 16, NF 45 ± 3 W/m2; P = 0.04) and greater at 42 °C (F 125 ± 1, NF 74 ± 3 W/m2; P < 0.01) with fan use. However, fan use resulted in a greater Emax at baseline humidity at both 36 °C (F 343 ± 10, NF 153 ± 5 W/m2; P < 0.01) and 42 °C (F 376 ± 13, NF 161 ± 4 W/m2; P < 0.01) and throughout the incremental increases in humidity. Within the humidity range that a rise in HR was prevented by fan use but not without a fan, LSR was higher in NF at both 36 °C (P = 0.04) and 42 °C (P = 0.05), and skin temperature was higher in NF at 42 °C (P = 0.05), but no differences in CVC or core temperatures were observed (all P > 0.05). These results suggest that the delayed increase in heart rate with fan use during extreme heat and humidity is associated with improved evaporative efficiency.

  17. The biophysical and physiological basis for mitigated elevations in heart rate with electric fan use in extreme heat and humidity

    NASA Astrophysics Data System (ADS)

    Ravanelli, Nicholas M.; Gagnon, Daniel; Hodder, Simon G.; Havenith, George; Jay, Ollie

    2017-02-01

    Electric fan use in extreme heat wave conditions has been thought to be disadvantageous because it might accelerate heat gain to the body via convection. However, it has been recently shown that fan use delays increases in heart rate even at high temperatures (42 °C) in young adults. We here assess the biophysical and physiological mechanisms underlying the apparently beneficial effects of fan use. Eight males (24 ± 3 y; 80.7 ± 11.7 kg; 2.0 ± 0.1 m2) rested at either 36 °C or 42 °C, with (F) or without (NF) electric fan use (4.2 m/s) for 120 min while humidity increased every 7.5 min by 0.3 kPa from a baseline value of 1.6 kPa. Heart rate (HR), local sweat rate (LSR), cutaneous vascular conductance (CVC), core and mean skin temperatures, and the combined convective/radiative heat loss (C+R), evaporative heat balance requirements (Ereq) and maximum evaporative potential (Emax) were assessed. C+R was greater with fan use at 36 °C (F 8 ± 6, NF 2 ± 2 W/m2; P = 0.04) and more negative (greater dry heat gain) with fan use at 42 °C (F -78 ± 4, NF -27 ± 2 W/m2; P < 0.01). Consequently, Ereq was lower at 36 °C (F 38 ± 16, NF 45 ± 3 W/m2; P = 0.04) and greater at 42 °C (F 125 ± 1, NF 74 ± 3 W/m2; P < 0.01) with fan use. However, fan use resulted in a greater Emax at baseline humidity at both 36 °C (F 343 ± 10, NF 153 ± 5 W/m2; P < 0.01) and 42 °C (F 376 ± 13, NF 161 ± 4 W/m2; P < 0.01) and throughout the incremental increases in humidity. Within the humidity range that a rise in HR was prevented by fan use but not without a fan, LSR was higher in NF at both 36 °C ( P = 0.04) and 42 °C ( P = 0.05), and skin temperature was higher in NF at 42 °C ( P = 0.05), but no differences in CVC or core temperatures were observed (all P > 0.05). These results suggest that the delayed increase in heart rate with fan use during extreme heat and humidity is associated with improved evaporative efficiency.

  18. Measuring the heat exchange of a quantum process.

    PubMed

    Goold, John; Poschinger, Ulrich; Modi, Kavan

    2014-08-01

    Very recently, interferometric methods have been proposed to measure the full statistics of work performed on a driven quantum system [Dorner et al., Phys. Rev. Lett. 110, 230601 (2013) and Mazzola et al., Phys. Rev. Lett. 110, 230602 (2013)]. The advantage of such schemes is that they replace the necessity to make projective measurements by performing phase estimation on an appropriately coupled ancilla qubit. These proposals are one possible route to the tangible experimental exploration of quantum thermodynamics, a subject which is the center of much current attention due to the current control of mesoscopic quantum systems. In this Rapid Communication we demonstrate that a modification of the phase estimation protocols can be used in order to measure the heat distribution of a quantum process. In addition, we demonstrate how our scheme maybe implemented using ion trap technology. Our scheme should pave the way for experimental explorations of the Landauer principle and hence the intricate energy to information conversion in mesoscopic quantum systems.

  19. A methodological frame for assessing benzene induced leukemia risk mitigation due to policy measures.

    PubMed

    Karakitsios, Spyros P; Sarigiannis, Dimosthenis Α; Gotti, Alberto; Kassomenos, Pavlos A; Pilidis, Georgios A

    2013-01-15

    The study relies on the development of a methodology for assessing the determinants that comprise the overall leukemia risk due to benzene exposure and how these are affected by outdoor and indoor air quality regulation. An integrated modeling environment was constructed comprising traffic emissions, dispersion models, human exposure models and a coupled internal dose/biology-based dose-response risk assessment model, in order to assess the benzene imposed leukemia risk, as much as the impact of traffic fleet renewal and smoking banning to these levels. Regarding traffic fleet renewal, several "what if" scenarios were tested. The detailed full-chain methodology was applied in a South-Eastern European urban setting in Greece and a limited version of the methodology in Helsinki. Non-smoking population runs an average risk equal to 4.1·10(-5) compared to 23.4·10(-5) for smokers. The estimated lifetime risk for the examined occupational groups was higher than the one estimated for the general public by 10-20%. Active smoking constitutes a dominant parameter for benzene-attributable leukemia risk, much stronger than any related activity, occupational or not. From the assessment of mitigation policies it was found that the associated leukemia risk in the optimum traffic fleet scenario could be reduced by up to 85% for non-smokers and up to 8% for smokers. On the contrary, smoking banning provided smaller gains for (7% for non-smokers, 1% for smokers), while for Helsinki, smoking policies were found to be more efficient than traffic fleet renewal. The methodology proposed above provides a general framework for assessing aggregated exposure and the consequent leukemia risk from benzene (incorporating mechanistic data), capturing exposure and internal dosimetry dynamics, translating changes in exposure determinants to actual changes in population risk, providing a valuable tool for risk management evaluation and consequently to policy support.

  20. The Pepcon Disaster-Causative Factors and potential Preventive and Mitigative Measures

    SciTech Connect

    Lambert, H E; Alvares, N J

    2003-07-25

    On May 4, 1988, the PEPCON plant experienced three major and several smaller explosions that caused over $70 million in property damage and caused two deaths. The PEPCON plant produced Ammonium Perchlorate (AP), a major ingredient for rocket fuel. The PEPCON plant and the nearby Kidd Marshmallow plant were totally destroyed by the detonations. The initiating event for the explosions was a fire that originated in the Batch Dryer Building and spread to adjacent storage. Several factors combined to cause the AP in the major storage fields to detonate, the most important being lack of adequate separation between storage units. Welding and flame cutting procedure with poor fire watch protocol was the prime candidate for fire ignition. There were no automatic fire suppression systems at the plant. Buildings including the Batch Dryer Building were made of combustible building material (fiberglass). There was poor housekeeping and no control of AP dust generation. AP was stored in combustible polyethylene drums, aluminum tote bins, 30-gallon steel storage drums and fiber reinforced tote bags. There were high-density storage practices. In addition, a contributing factor to the rapid fire-spread was that the wind that day was blowing directly from the batch dryer building to the storage areas. This paper claims that if codes, standards, and well-known hazard identification safety techniques were implemented at PEPCON, then the disaster would have been averted. A limited scope probabilistic risk assessment was conducted to establish the effectiveness of various preventive and mitigative features that could have been deployed to avert the disaster. The major hazard at the PEPCON site was fire and explosion involving the processing, production and storage of AP, which was then and is currently stored as a class 4 oxidizer. Since minute quantities of contamination can cause AP to be detonable by shock, there has been an ongoing debate concerning its reclassification to a class

  1. An anatomically realistic temperature phantom for radiofrequency heating measurements

    PubMed Central

    Graedel, Nadine N.; Polimeni, Jonathan R.; Guerin, Bastien; Gagoski, Borjan; Wald, Lawrence L.

    2014-01-01

    Purpose An anthropomorphic phantom with realistic electrical properties allows for a more accurate reproduction of tissue current patterns during excitation. A temperature map can then probe the worst-case heating expected in the un-perfused case. We describe an anatomically realistic human head phantom that allows rapid 3D temperature mapping at 7 T. Methods The phantom was based on hand-labeled anatomical imaging data and consists of four compartments matching the corresponding human tissues in geometry and electrical properties. The increases in temperature resulting from radiofrequency excitation were measured with MR thermometry using a temperature sensitive contrast agent (TmDOTMA−) validated by direct fiber optic temperature measurements. Results Acquisition of 3D temperature maps of the full phantom with a temperature accuracy better than 0.1°C was achieved with an isotropic resolution of 5 mm and acquisition times of 2–4 minutes. Conclusion Our results demonstrate the feasibility of constructing anatomically realistic phantoms with complex geometries incorporating the ability to measure accurate temperature maps in the phantom. The anthropomorphic temperature phantom is expected to provide a useful tool for the evaluation of the heating effects of both conventional and parallel transmit pulses and help validate electromagnetic and temperature simulations. PMID:24549755

  2. Emission Measure Distribution and Heating of Two Active Region Cores

    NASA Technical Reports Server (NTRS)

    Tripathi, Durgesh; Klimchuk, James A.; Mason, Helen E.

    2011-01-01

    Using data from the Extreme-ultraviolet Imaging Spectrometer aboard Hinode, we have studied the coronal plasma in the core of two active regions. Concentrating on the area between opposite polarity moss, we found emission measure distributions having an approximate power-law form EM/T(exp 2.4) from log T = 5.55 up to a peak at log T = 6.57. The observations are explained extremely well by a simple nanoflare model. However, in the absence of additional constraints, the observations could possibly also be explained by steady heating.

  3. Importation of beef from countries infected with foot and mouth disease: a review of risk mitigation measures.

    PubMed

    Sutmoller, P

    2001-12-01

    Risk mitigation measures to reduce the risks associated with importing beef from countries affected by foot and mouth disease (FMD) consist of controls at the farm of origin, inspection of slaughterhouses and maturation and deboning of carcasses. This assessment evaluates the effect of these measures on the mitigation of the risks presented by meat from cattle with FMD, for each of the different stages of the disease. The four disease stages considered are the incubation period, the period of clinical signs, convalescence and the carrier stage. Efficient animal health systems, disease surveillance, and ante-mortem and post-mortem inspection of all cattle effectively reduce the risk of FMD transmission from cattle slaughtered during the period of clinical signs or convalescence. These measures fail if the cattle are slaughtered during the incubation period, because of the absence of clinical signs. Cattle in this stage of the infection are likely to be viraemic, with FMD virus present in the skeletal muscles. Maturation of the carcasses of viraemic cattle reduces the risk of virus presence in the beef. In addition, deboning and removal of the principal lymph nodes and large blood vessels eliminate a source of FMD contamination of the beef. However, the slaughter of viraemic cattle creates an additional hazard of gross environmental viral contamination of the slaughterhouse facilities. Therefore, the maturation process may create a false sense of security, and the emphasis should instead be placed on disease surveillance within the infected zone and on the farms of origin, to prevent the slaughter of herds that are incubating FMD. Cattle slaughtered during the carrier stage do not pose a risk for the international beef trade.

  4. The biophysical and physiological basis for mitigated elevations in heart rate with electric fan use in extreme heat and humidity.

    PubMed

    Ravanelli, Nicholas M; Gagnon, Daniel; Hodder, Simon G; Havenith, George; Jay, Ollie

    2017-02-01

    Electric fan use in extreme heat wave conditions has been thought to be disadvantageous because it might accelerate heat gain to the body via convection. However, it has been recently shown that fan use delays increases in heart rate even at high temperatures (42 °C) in young adults. We here assess the biophysical and physiological mechanisms underlying the apparently beneficial effects of fan use. Eight males (24 ± 3 y; 80.7 ± 11.7 kg; 2.0 ± 0.1 m(2)) rested at either 36 °C or 42 °C, with (F) or without (NF) electric fan use (4.2 m/s) for 120 min while humidity increased every 7.5 min by 0.3 kPa from a baseline value of 1.6 kPa. Heart rate (HR), local sweat rate (LSR), cutaneous vascular conductance (CVC), core and mean skin temperatures, and the combined convective/radiative heat loss (C+R), evaporative heat balance requirements (Ereq) and maximum evaporative potential (Emax) were assessed. C+R was greater with fan use at 36 °C (F 8 ± 6, NF 2 ± 2 W/m(2); P = 0.04) and more negative (greater dry heat gain) with fan use at 42 °C (F -78 ± 4, NF -27 ± 2 W/m(2); P < 0.01). Consequently, Ereq was lower at 36 °C (F 38 ± 16, NF 45 ± 3 W/m(2); P = 0.04) and greater at 42 °C (F 125 ± 1, NF 74 ± 3 W/m(2); P < 0.01) with fan use. However, fan use resulted in a greater Emax at baseline humidity at both 36 °C (F 343 ± 10, NF 153 ± 5 W/m(2); P < 0.01) and 42 °C (F 376 ± 13, NF 161 ± 4 W/m(2); P < 0.01) and throughout the incremental increases in humidity. Within the humidity range that a rise in HR was prevented by fan use but not without a fan, LSR was higher in NF at both 36 °C (P = 0.04) and 42 °C (P = 0.05), and skin temperature was higher in NF at 42 °C (P = 0.05), but no differences in CVC or core temperatures were observed (all P > 0.05). These results suggest that the delayed increase in heart rate with fan use during extreme heat and humidity is associated with improved

  5. Endwall Heat Transfer Measurements in a Transonic Turbine Cascade

    NASA Technical Reports Server (NTRS)

    Giel, P. W.; Thurman, D. R.; VanFossen, G. J.; Hippensteele, S. A.; Boyle, R. J.

    1996-01-01

    Turbine blade endwall heat transfer measurements are given for a range of Reynolds and Mach numbers. Data were obtained for Reynolds numbers based on inlet conditions of 0.5 and 1.0 x 106, for isentropic exit Mach numbers of 1.0 and 1.3, and for freestream turbulence intensities of 0.25% and 7.0%. Tests were conducted in a linear cascade at the NASA Lewis Transonic Turbine Blade Cascade Facility. The test article was a turbine rotor with 136' of turning and an axial chord of 12.7 cm. The large scale allowed for very detailed measurements of both flow field and surface phenomena. The intent of the work is to provide benchmark quality data for computational fluid dynamics (CFD) code and model verification. The flow field in the cascade is highly three-dimensional as a result of thick boundary layers at the test section inlet. Endwall heat transfer data were obtained using a steady-state liquid crystal technique.

  6. Imaging Thomson scattering measurements of radiatively heated Xe

    SciTech Connect

    Pollock, B; Meinecke, J; Kuschel, S; Ross, J S; Divol, L; Glenzer, S H; Tynan, G R

    2012-05-01

    Uniform density and temperature Xe plasmas have been produced over >4 mm scale-lengths using x-rays generated in a cylindrical Pb cavity. The cavity is 750 {micro}m in depth and diameter, and is heated by a 300 J, 2 ns square, 1054 nm laser pulse focused to a spot size of 200 {micro}m at the cavity entrance. The plasma is characterized by simultaneous imaging Thomson scattering measurements from both the electron and ion scattering features. The electron feature measurement determines the spatial electron density and temperature profile, and using these parameters as constraints in the ion feature analysis allows an accurate determination of the charge state of the Xe ions. The Thomson scattering probe beam is 40 J, 200 ps, and 527 nm, and is focused to a 100 {micro}m spot size at the entrance of the Pb cavity. Each system has a spatial resolution of 25 {micro}m, a temporal resolution of 200 ps (as determined by the probe duration), and a spectral resolution of 2 nm for the electron feature system and 0.025 nm for the ion feature system. The experiment is performed in a Xe filled target chamber at a neutral pressure of 3-10 Torr, and the x-rays produced in the Pb ionize and heat the Xe to a charge state of 20 {+-} 4 at up to 200 eV electron temperatures.

  7. Thermal conductivity measurements of proton-heated warm dense matter

    NASA Astrophysics Data System (ADS)

    McKelvey, A.; Fernandez-Panella, A.; Hua, R.; Kim, J.; King, J.; Sio, H.; McGuffey, C.; Kemp, G. E.; Freeman, R. R.; Beg, F. N.; Shepherd, R.; Ping, Y.

    2015-06-01

    Accurate knowledge of conductivity characteristics in the strongly coupled plasma regime is extremely important for ICF processes such as the onset of hydrodynamic instabilities, thermonuclear burn propagation waves, shell mixing, and efficient x-ray conversion of indirect drive schemes. Recently, an experiment was performed on the Titan laser platform at the Jupiter Laser Facility to measure the thermal conductivity of proton-heated warm dense matter. In the experiment, proton beams generated via target normal sheath acceleration were used to heat bi-layer targets with high-Z front layers and lower-Z back layers. The stopping power of a material is approximately proportional to Z2 so a sharp temperature gradient is established between the two materials. The subsequent thermal conduction from the higher-Z material to the lower-Z was measured with time resolved streaked optical pyrometry (SOP) and Fourier domain interferometry (FDI) of the rear surface. Results will be used to compare predictions from the thermal conduction equation and the Wiedemann-Franz Law in the warm dense matter regime. Data from the time resolved diagnostics for Au/Al and Au/C Targets of 20-200 nm thickness will be presented.

  8. Effects of heat stress on some reproductive parameters of male cavie (Cavia porcellus) and mitigation strategies using guava (Psidium guajava) leaves essential oil.

    PubMed

    Ngoula, Ferdinand; Guemdjo Tekam, Maryvonne; Kenfack, Augustave; Tadondjou Tchingo, Cyrille D'Alex; Nouboudem, Sandrine; Ngoumtsop, Herman; Tsafack, Borice; Teguia, Alexis; Kamtchouing, Pierre; Galeotti, Marco; Tchoumboue, Joseph

    2017-02-01

    Climate changes, particularly the increase of temperature are among the main causes behind the decline of fertility in humans as well as animals. In this study, the effects of heat stress on some reproductive parameters of male cavies and mitigation strategies using guava leaves essential oil (GLEO) were studied. For this purpose, 40 male cavies aged 2.5-3 months and weighing between 348 and 446g were divided into 4 groups of 10 animals each and subjected to the following temperatures: Ambient temperature (20-25°C) for the control group, 35°C for group 1, 45°C for group 2 and 45°C+100µl GLEO/kg body weight, administered by gavage to animals for group 3. Exposure time of heat was 7h per day for 60 days. Results reveal that the relative weights of testes, epididymis, vas deferens and seminal vesicles were hardly affected by the temperature levels considered (P>0.05). The mass and individual sperm motility was significantly lower (P<0.05) in cavies exposed to the temperature of 35 and 45°C as compared with those which received GLEO and controls. The percentages of abnormal sperm and altered sperm DNA were higher in animals exposed to temperature of 35 and 45°C as compared with the controls. The activity of superoxide dismutase significantly increased (P<0.05) in animals exposed to temperature of 45°C and in those of 45°C and orally treated with GLEO, compared with cavies exposed to temperature of 45°C without receiving GLEO. The level of malondialdehyde was significantly increased (P<0.05) in animals exposed to temperature of 35 and 45°C, whereas the level of nitric oxide was significantly lower (P<0.05) in exposed animals as compared with controls. It was concluded that the exposure of male cavies at 35 and 45°C for 60 days induce heat stress that causes deterioration of sperm characteristics. These effects that can be mitigated by the administration of guava leaves essential oil.

  9. Bubbly flow velocity measurements near a heated cylindrical conductor

    SciTech Connect

    Canaan, R.E.; Hassan, Y.A. )

    1990-01-01

    The objective of this study is to apply recent advances and improvements in the digital pulsed laser velocimetry (DPLV) technique to the analysis of two-phase bubbly flow about a cylindrical conductor emitting a constant heat flux within a transparent rectangular enclosure. Pulsed laser velocimetry is a rapidly advancing fluid flow visualization technique that determines full-field instantaneous velocity vectors of a quantitative nature such that the flow field remains undisturbed by the measurement. The DPLV method offers several significant advantages over more traditional fluid velocity measurement techniques such as hot wire/film anemometry and laser Doppler anemometry because reliable instantaneous velocity data may be acquired over substantial flow areas in a single experiment.

  10. Analysis of a heat transfer device for measuring film coefficients

    NASA Technical Reports Server (NTRS)

    Medrow, R. A.; Johnson, R. L.; Loomis, W. R.; Wedeven, L. D.

    1975-01-01

    A heat transfer device consisting of a heated rotating cylinder in a bath was analyzed for its effectiveness to determine heat transfer coefficient of fluids. A time dependent analysis shows that the performance is insensitive to the value of heat transfer coefficient with the given rig configuration.

  11. Measurement and mitigation of methane emissions from beef cattle in tropical grazing systems: a perspective from Australia and Brazil.

    PubMed

    Berndt, A; Tomkins, N W

    2013-06-01

    The growing global demand for food of animal origin will be the incentive for countries such as Australia and Brazil to increase their beef production and international exports. This increased supply of beef is expected to occur primarily through on-farm productivity increases. The strategies for reducing resultant greenhouse gas (GHG) emissions should be evaluated in the context of the production system and should encompass a broader analysis, which would include the emissions of methane (CH4) and nitrous oxide (N2O) and carbon sequestration. This paper provides an insight into CH4 measurement techniques applicable to grazing environments and proposed mitigation strategies, with relevance to the production systems that are predominant in grazing systems of Australia and Brazil. Research and technology investment in both Australia and Brazil is aimed at developing measurement techniques and increasing the efficiency of cattle production by improving herd genetics, utilization of the seasonal feed-base and reducing the proportion of metabolizable energy lost as CH4. Concerted efforts in these areas can be expected to reduce the number of unproductive animals, reduce age at slaughter and inevitably reduce emission intensity (EI) from beef production systems. Improving efficiency of livestock production systems in tropical grazing systems for Australia and Brazil will be based on cultivated and existing native pastures and the use of additives and by-products from other agricultural sectors. This approach spares grain-based feed reserves typically used for human consumption, but potentially incurs a heavier EI than current intensive feeding systems. The determination of GHG emissions and the value of mitigation outcomes for entire beef production systems in the extensive grazing systems is complex and require a multidisciplinary approach. It is fortunate that governments in both Australia and Brazil are supporting ongoing research activities. Nevertheless, to achieve

  12. Heterogeneity in individually experienced temperatures (IETs) within an urban neighborhood: insights from a new approach to measuring heat exposure

    NASA Astrophysics Data System (ADS)

    Kuras, E. R.; Hondula, D. M.; Brown-Saracino, J.

    2015-10-01

    Urban environmental health hazards, including exposure to extreme heat, have become increasingly important to understand in light of ongoing climate change and urbanization. In cities, neighborhoods are often considered a homogenous and appropriate unit with which to assess heat risk. This manuscript presents results from a pilot study examining the variability of individually experienced temperatures (IETs) within a single urban neighborhood. In July 2013, 23 research participants were recruited from the South End neighborhood of Boston and equipped with Thermochron iButtons that measured the air temperatures surrounding individuals as they went about their daily lives. IETs were measured during a heat wave period (July 17-20), which included 2 days with excessive heat warnings and 1 day with a heat advisory, as well as a reference period (July 20-23) in which temperatures were below seasonal averages. IETs were not homogeneous during the heat wave period; mean IETs were significantly different between participants ( p < 0.001). The majority of participants recorded IETs significantly lower than outdoor ambient temperatures (OATs), and on average, the mean IET was 3.7 °C below the mean OAT. Compared with IETs during the reference period, IETs during the heat wave period were 1.0 °C higher. More than half of participants did not experience statistically different temperatures between the two test periods, despite the fact that the mean OAT was 6.5 °C higher during the heat wave period. The IET data collected for this sample and study period suggest that (1) heterogeneity in individual heat exposure exists within this neighborhood and that (2) outdoor temperatures misrepresent the mean experienced temperatures during a heat wave period. Individual differences in attributes (gender, race, socioeconomic status, etc.), behaviors (schedules, preferences, lifestyle, etc.), and access to resources are overlooked determinants of heat exposure and should be better

  13. 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.

  14. Mitigation Action Plan

    SciTech Connect

    Not Available

    1994-02-01

    This Mitigation Action Plan (MAP) focuses on mitigation commitments stated in the Supplemental Environmental Impact Statement (SEIS) and the Record of Decision (ROD) for the Naval Petroleum Reserve No. 1 (NPR-1). Specific commitments and mitigation implementation actions are listed in Appendix A-Mitigation Actions, and form the central focus of this MAP. They will be updated as needed to allow for organizational, regulatory, or policy changes. It is the intent of DOE to comply with all applicable federal, state, and local environmental, safety, and health laws and regulations. Eighty-six specific commitments were identified in the SEIS and associated ROD which pertain to continued operation of NPR-1 with petroleum production at the Maximum Efficient Rate (MER). The mitigation measures proposed are expected to reduce impacts as much as feasible, however, as experience is gained in actual implementation of these measures, some changes may be warranted.

  15. PRECISE MEASUREMENT OF THE REIONIZATION OPTICAL DEPTH FROM THE GLOBAL 21 cm SIGNAL ACCOUNTING FOR COSMIC HEATING

    SciTech Connect

    Fialkov, Anastasia; Loeb, Abraham E-mail: aloeb@cfa.harvard.edu

    2016-04-10

    As a result of our limited data on reionization, the total optical depth for electron scattering, τ, limits precision measurements of cosmological parameters from the Cosmic Microwave Background (CMB). It was recently shown that the predicted 21 cm signal of neutral hydrogen contains enough information to reconstruct τ with sub-percent accuracy, assuming that the neutral gas was much hotter than the CMB throughout the entire epoch of reionization (EoR). Here we relax this assumption and use the global 21 cm signal alone to extract τ for realistic X-ray heating scenarios. We test our model-independent approach using mock data for a wide range of ionization and heating histories and show that an accurate measurement of the reionization optical depth at a sub-percent level is possible in most of the considered scenarios even when heating is not saturated during the EoR, assuming that the foregrounds are mitigated. However, we find that in cases where heating sources had hard X-ray spectra and their luminosity was close to or lower than what is predicted based on low-redshift observations, the global 21 cm signal alone is not a good tracer of the reionization history.

  16. Precise Measurement of the Reionization Optical Depth from the Global 21 cm Signal Accounting for Cosmic Heating

    NASA Astrophysics Data System (ADS)

    Fialkov, Anastasia; Loeb, Abraham

    2016-04-01

    As a result of our limited data on reionization, the total optical depth for electron scattering, τ, limits precision measurements of cosmological parameters from the Cosmic Microwave Background (CMB). It was recently shown that the predicted 21 cm signal of neutral hydrogen contains enough information to reconstruct τ with sub-percent accuracy, assuming that the neutral gas was much hotter than the CMB throughout the entire epoch of reionization (EoR). Here we relax this assumption and use the global 21 cm signal alone to extract τ for realistic X-ray heating scenarios. We test our model-independent approach using mock data for a wide range of ionization and heating histories and show that an accurate measurement of the reionization optical depth at a sub-percent level is possible in most of the considered scenarios even when heating is not saturated during the EoR, assuming that the foregrounds are mitigated. However, we find that in cases where heating sources had hard X-ray spectra and their luminosity was close to or lower than what is predicted based on low-redshift observations, the global 21 cm signal alone is not a good tracer of the reionization history.

  17. The measurement of heat flux from initiators in solid propellant rocket igniters

    NASA Astrophysics Data System (ADS)

    Subba Rao, S. V.; Ramesh, N.; Pillai, B. C.

    The use of ribbon thermocouples to measure the heat flux from the initiator jet of a solid propellant rocket igniter and received by the booster charge is reported. Heat flux histories are given. All the heat flux curves showed a sharp peak within a short operation of 1 ms. Peak heat flux values extended up to 16,000 W/sq cm.

  18. Development of a laser-induced heat flux technique for measurement of convective heat transfer coefficients in a supersonic flowfield

    NASA Technical Reports Server (NTRS)

    Porro, A. Robert; Keith, Theo G., Jr.; Hingst, Warren R.; Chriss, Randall M.; Seablom, Kirk D.

    1991-01-01

    A technique is developed to measure the local convective heat transfer coefficient on a model surface in a supersonic flow field. The technique uses a laser to apply a discrete local heat flux at the model test surface, and an infrared camera system determines the local temperature distribution due to heating. From this temperature distribution and an analysis of the heating process, a local convective heat transfer coefficient is determined. The technique was used to measure the load surface convective heat transfer coefficient distribution on a flat plate at nominal Mach numbers of 2.5, 3.0, 3.5, and 4.0. The flat plate boundary layer initially was laminar and became transitional in the measurement region. The experimental results agreed reasonably well with theoretical predictions of convective heat transfer of flat plate laminar boundary layers. The results indicate that this non-intrusive optical measurement technique has the potential to obtain high quality surface convective heat transfer measurements in high speed flowfields.

  19. 49 CFR 192.935 - What additional preventive and mitigative measures must an operator take?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... accordance with one of the risk assessment approaches in ASME/ANSI B31.8S (incorporated by reference, see § 192.7), section 5, a risk analysis of its pipeline to identify additional measures to protect the high.... (2) Outside force damage. If an operator determines that outside force (e.g., earth movement,...

  20. 49 CFR 192.935 - What additional preventive and mitigative measures must an operator take?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... accordance with one of the risk assessment approaches in ASME/ANSI B31.8S (incorporated by reference, see § 192.7), section 5, a risk analysis of its pipeline to identify additional measures to protect the high.... (2) Outside force damage. If an operator determines that outside force (e.g., earth movement,...

  1. Dynamical properties measurements for asteroid, comet and meteorite material applicable to impact modeling and mitigation calculations

    SciTech Connect

    Furnish, M.D.; Boslough, M.B.; Gray, G.T. III; Remo, J.L.

    1994-07-01

    We describe methods for measuring dynamical properties for two material categories of interest in understanding large-scale extraterrestrial impacts: iron-nickel and underdense materials (e.g. snow). Particular material properties measured by the present methods include Hugoniot release paths and constitutive properties (stress vs. strain). The iron-nickel materials lend themselves well to conventional shock and quasi-static experiments. As examples, a suite of experiments is described including six impact tests (wave profile compression/release) over the stress range 2--20 GPa, metallography, quasi-static and split Hopkinson pressure bar (SHPB) mechanical testing, and ultrasonic mapping and sound velocity measurements. Temperature sensitivity of the dynamic behavior was measured at high and low strain rates. Among the iron-nickel materials tested, an octahedrite was found to have behavior close to that of Armco iron under shock and quasi-static conditions, while an ataxite exhibited a significantly larger quasi-static yield strength than did the octahedrite or a hexahedrite. The underdense materials pose three primary experimental difficulties. First, the samples are friable; they can melt or sublimate during storage, preparation and testing. Second, they are brittle and crushable; they cannot withstand such treatment as traditional machining or launch in a gun system. Third, with increasing porosity the calculated Hugoniot density becomes rapidly more sensitive to errors in wave time-of-arrival measurements. Carefully chosen simulants eliminate preservation (friability) difficulties, but the other difficulties remain. A family of 36 impact tests was conducted on snow and snow simulants at Sandia, yielding reliable Hugoniot and reshock states, but limited release property information. Other methods for characterizing these materials are discussed.

  2. Remote Measurement of Heat Flux from Power Plant Cooling Lakes

    SciTech Connect

    Garrett, Alfred J.; Kurzeja, Robert J.; Villa-Aleman, Eliel; Bollinger, James S.; Pendergast, Malcolm M.

    2013-06-01

    Laboratory experiments have demonstrated a correlation between the rate of heat loss q" from an experimental fluid to the air above and the standard deviation σ of the thermal variability in images of the fluid surface. These experimental results imply that q" can be derived directly from thermal imagery by computing σ. This paper analyses thermal imagery collected over two power plant cooling lakes to determine if the same relationship exists. Turbulent boundary layer theory predicts a linear relationship between q" and σ when both forced (wind driven) and free (buoyancy driven) convection are present. Datasets derived from ground- and helicopter-based imagery collections had correlation coefficients between σ and q" of 0.45 and 0.76, respectively. Values of q" computed from a function of σ and friction velocity u* derived from turbulent boundary layer theory had higher correlations with measured values of q" (0.84 and 0.89). Finally, this research may be applicable to the problem of calculating losses of heat from the ocean to the atmosphere during high-latitude cold-air outbreaks because it does not require the information typically needed to compute sensible, evaporative, and thermal radiation energy losses to the atmosphere.

  3. Measuring the clustering of photometric quasars through blind mitigation of systematics

    NASA Astrophysics Data System (ADS)

    Leistedt, Boris; Peiris, Hiranya V.; Roth, Nina

    2014-05-01

    We present accurate measurements of the large-scale clustering of photometric quasars from the Sloan Digital Sky Survey. These results, detailed in Leistedt & Peiris (2014), rely on a novel technique to identify and treat systematics when measuring angular power spectra, using null-tests and analytical marginalisation. This approach can be used to maximise the extraction of information from current and future galaxy or quasar surveys. For example, it enables to robustly constrain primordial non-Gaussianity (PNG), which modifies the bias of galaxies and quasars on large scales - the most sensitive to observational systematics. The constraints on PNG obtained with the quasar power spectra are detailed in Leistedt, Peiris & Roth (2014); these are the most stringent constraints to date obtained with a single tracer of the large-scale structure.

  4. Differential heating: A versatile method for thermal conductivity measurements in high-energy-density matter

    NASA Astrophysics Data System (ADS)

    Ping, Y.; Fernandez-Panella, A.; Sio, H.; Correa, A.; Shepherd, R.; Landen, O.; London, R. A.; Sterne, P. A.; Whitley, H. D.; Fratanduono, D.; Boehly, T. R.; Collins, G. W.

    2015-09-01

    We propose a method for thermal conductivity measurements of high energy density matter based on differential heating. A temperature gradient is created either by surface heating of one material or at an interface between two materials by different energy deposition. The subsequent heat conduction across the temperature gradient is observed by various time-resolved probing techniques. Conceptual designs of such measurements using laser heating, proton heating, and x-ray heating are presented. The sensitivity of the measurements to thermal conductivity is confirmed by simulations.

  5. Differential heating: A versatile method for thermal conductivity measurements in high-energy-density matter

    DOE PAGES

    Ping, Y.; Fernandez-Panella, A.; Sio, H.; ...

    2015-09-04

    We propose a method for thermal conductivity measurements of high energy density matter based on differential heating. A temperature gradient is created either by surface heating of one material or at an interface between two materials by different energy deposition. The subsequent heat conduction across the temperature gradient is observed by various time-resolved probing techniques. Conceptual designs of such measurements using laser heating, proton heating, and x-ray heating are presented. As a result, the sensitivity of the measurements to thermal conductivity is confirmed by simulations.

  6. Differential heating: A versatile method for thermal conductivity measurements in high-energy-density matter

    SciTech Connect

    Ping, Y.; Fernandez-Panella, A.; Correa, A.; Shepherd, R.; Landen, O.; London, R. A.; Sterne, P. A.; Whitley, H. D.; Fratanduono, D.; Collins, G. W.; Sio, H.; Boehly, T. R.

    2015-09-15

    We propose a method for thermal conductivity measurements of high energy density matter based on differential heating. A temperature gradient is created either by surface heating of one material or at an interface between two materials by different energy deposition. The subsequent heat conduction across the temperature gradient is observed by various time-resolved probing techniques. Conceptual designs of such measurements using laser heating, proton heating, and x-ray heating are presented. The sensitivity of the measurements to thermal conductivity is confirmed by simulations.

  7. Formaldehyde and acetaldehyde exposure mitigation in US residences: In-home measurements of ventilation control and source control

    SciTech Connect

    Hult, Erin L.; Willem, Henry; Price, Phillip N.; Hotchi, Toshifumi; Russell, Marion L.; Singer, Brett C.

    2014-10-01

    Measurements were taken in new US residences to assess the extent to which ventilation and source control can mitigate formaldehyde exposure. Increasing ventilation consistently lowered indoor formaldehyde concentrations. However, at a reference air exchange rate of 0.35 h-1, increasing ventilation was up to 60% less effective than would be predicted if the emission rate were constant. This is consistent with formaldehyde emission rates decreasing as air concentrations increase, as observed in chamber studies. In contrast, measurements suggest acetaldehyde emission was independent of ventilation rate. To evaluate the effectiveness of source control, formaldehyde concentrations were measured in Leadership in Energy and Environmental Design (LEED) certified/Indoor airPLUS homes constructed with materials certified to have low emission rates of volatile organic compounds (VOC). At a reference air exchange rate of 0.35 h-1, and adjusting for home age, temperature and relative humidity, formaldehyde concentrations in homes built with low-VOC materials were 42% lower on average than in reference new homes with conventional building materials. Without adjustment, concentrations were 27% lower in the low-VOC homes. The mean and standard deviation of formaldehyde concentration were 33 μg m-3 and 22 μg m-3 for low-VOC homes and 45 μg m-3 and 30 μg m-3 for conventional.

  8. Formaldehyde and acetaldehyde exposure mitigation in US residences: in-home measurements of ventilation control and source control.

    PubMed

    Hult, E L; Willem, H; Price, P N; Hotchi, T; Russell, M L; Singer, B C

    2015-10-01

    Measurements were taken in new US residences to assess the extent to which ventilation and source control can mitigate formaldehyde exposure. Increasing ventilation consistently lowered indoor formaldehyde concentrations. However, at a reference air exchange rate of 0.35 h(-1), increasing ventilation was up to 60% less effective than would be predicted if the emission rate were constant. This is consistent with formaldehyde emission rates decreasing as air concentrations increase, as observed in chamber studies. In contrast, measurements suggest acetaldehyde emission was independent of ventilation rate. To evaluate the effectiveness of source control, formaldehyde concentrations were measured in Leadership in Energy and Environmental Design (LEED)-certified/Indoor airPLUS homes constructed with materials certified to have low emission rates of volatile organic compounds (VOC). At a reference air exchange rate of 0.35 h(-1), and adjusting for home age, temperature and relative humidity, formaldehyde concentrations in homes built with low-VOC materials were 42% lower on average than in reference new homes with conventional building materials. Without adjustment, concentrations were 27% lower in the low-VOC homes. The mean and standard deviation of formaldehyde concentration was 33 μg/m(3) and 22 μg/m(3) for low-VOC homes and 45 μg/m(3) and 30 μg/m(3) for conventional.

  9. Measurement of natural convective heat transfer coefficient along the surface of a heated wire using digital holographic interferometry.

    PubMed

    Kumar, Varun; Kumar, Manoj; Shakher, Chandra

    2014-09-20

    In this paper, the local convective heat transfer coefficient (h) is measured along the surface of an electrically heated vertical wire using digital holographic interferometry (DHI). Experiments are conducted on wires of different diameters. The experimentally measured values are within the range as given in the literature. DHI is expected to provide a more accurate local convective heat transfer coefficient (h) as the value of the temperature gradient required for the calculation of "h" can be obtained more accurately than by other existing optical interferometric techniques without the use of a phase shifting technique. This is because in digital holography phase measurement accuracy is expected to be higher.

  10. Mitigation Monitoring Plan

    SciTech Connect

    Not Available

    1992-09-01

    The Final Supplemental Environmental Impact Report (SEIR) (September 1992) for the Proposed Renewal of the Contract between the United States Department of Energy and The Regents of the University of California for the Operation and Management of the Lawrence Berkeley Laboratory identifies the environmental impacts associated with renewing the contract and specifies a series of measures designed to mitigate adverse impacts to the environment. This Mitigation Monitoring Plan describes the procedures the University will use to implement the mitigation measures adopted in connection with the approval of the Contract.

  11. Resonance Frequency of Optical Microbubble Resonators: Direct Measurements and Mitigation of Fluctuations

    PubMed Central

    Cosci, Alessandro; Berneschi, Simone; Giannetti, Ambra; Farnesi, Daniele; Cosi, Franco; Baldini, Francesco; Nunzi Conti, Gualtiero; Soria, Silvia; Barucci, Andrea; Righini, Giancarlo; Pelli, Stefano

    2016-01-01

    This work shows the improvements in the sensing capabilities and precision of an Optical Microbubble Resonator due to the introduction of an encaging poly(methyl methacrylate) (PMMA) box. A frequency fluctuation parameter σ was defined as a score of resonance stability and was evaluated in the presence and absence of the encaging system and in the case of air- or water-filling of the cavity. Furthermore, the noise interference introduced by the peristaltic and the syringe pumping system was studied. The measurements showed a reduction of σ in the presence of the encaging PMMA box and when the syringe pump was used as flowing system. PMID:27589761

  12. Correlation of Nonlinear Distortion in Digital Phased Arrays: Measurement and Mitigation

    DTIC Science & Technology

    2010-08-26

    c o CD CD CD « 8 & co a: .2 1 1 o o o c gp -1 0 E 0 E CO a) CÜ 75 𔃿> Q ^ ps < CO l-Q Q ^ a: <>- «§ hi < CO...M ^te CM a> co F= b 3 ’ a- CM *-• 0) X o U- CM E "" 4P " CO 3 o J F— c...describes the results of recent experiments involving a four -channel digital receiver system. The system was used to measure the correlation (between

  13. Film-Cooling Heat-Transfer Measurements Using Liquid Crystals

    NASA Technical Reports Server (NTRS)

    Hippensteele, Steven A.

    1997-01-01

    The following topics are discussed: (1) The Transient Liquid-Crystal Heat-Transfer Technique; (2) 2-D Film-Cooling Heat-Transfer on an AlliedSignal Vane; and (3) Effects of Tab Vortex Generators on Surface Heat Transfer. Downstream of a Jet in Crossflow.

  14. Major transport mechanisms of pyrethroids in residential settings and effects of mitigation measures.

    PubMed

    Davidson, Paul C; Jones, Russell L; Harbourt, Christopher M; Hendley, Paul; Goodwin, Gregory E; Slizy, Bradley A

    2014-01-01

    The major pathways for transport of pyrethroids were determined in runoff studies conducted at a full-scale test facility in central California, USA. The 6 replicate house lots were typical of front lawns and house fronts of California residential developments and consisted of stucco walls, garage doors, driveways, and residential lawn irrigation sprinkler systems. Each of the 6 lots also included a rainfall simulator to generate artificial rainfall events. Different pyrethroids were applied to 5 surfaces—driveway, garage door and adjacent walls, lawn, lawn perimeter (grass near the house walls), and house walls above grass. The volume of runoff water from each house lot was measured, sampled, and analyzed to determine the amount of pyrethroid mass lost from each surface. Applications to 3 of the house lots were made using the application practices typically used prior to recent label changes, and applications were made to the other 3 house lots according to the revised application procedures. Results from the house lots using the historic application procedures showed that losses of the compounds applied to the driveway and garage door (including the adjacent walls) were 99.75% of total measured runoff losses. The greatest losses were associated with significant rainfall events rather than lawn irrigation events. However, runoff losses were 40 times less using the revised application procedures recently specified on pyrethroid labels.

  15. Mitigation measures for chromium-VI contaminated groundwater - The role of endophytic bacteria in rhizofiltration.

    PubMed

    Dimitroula, Helen; Syranidou, Evdokia; Manousaki, Eleni; Nikolaidis, Nikolaos P; Karatzas, George P; Kalogerakis, Nicolas

    2015-01-08

    A constructed wetland pilot with Juncus acutus L. plants was investigated for its rhizofiltration efficiency in treating Cr(VI)-contaminated groundwater. Measurements of Cr(VI) and total Cr were performed to estimate the rate of removal. In addition, Cr concentration in plant tissues was measured and the role of endophytic bacteria on plant's tolerance to Cr(VI) toxicity was investigated. The results support that J. acutus is able to rhizofiltrate Cr(VI) from contaminated water with up to 140μg/L while Cr content analysis in plant tissues revealed that the majority of Cr was accumulated by the plants. Moreover, two leaf (Acidovorax sp. strain U3 and Ralstonia sp. strain U36) isolated endophytic bacteria were found to tolerated 100mg/L Cr(VI) while nine root isolates showed resistance to 500mg/L Cr(VI). The endophytic bacteria Pseudomonas sp. strain R16 and Ochrobactrum sp. strain R24 were chosen for Cr(VI) reduction assays. All four strains exhibited a strong potential to reduce Cr(VI) to Cr(III) aerobically. Among them Pseudomonas sp. strain R16 was found able to completely reduced 100mg/L Cr(VI) after 150h of incubation. These results suggest that J. acutus is an excellent choice for CWs whose function is the removal of Cr(VI) from contaminated groundwater for subsequent use in crop irrigation.

  16. MAJOR TRANSPORT MECHANISMS OF PYRETHROIDS IN RESIDENTIAL SETTINGS AND EFFECTS OF MITIGATION MEASURES

    PubMed Central

    Davidson, Paul C; Jones, Russell L; Harbourt, Christopher M; Hendley, Paul; Goodwin, Gregory E; Sliz, Bradley A

    2014-01-01

    The major pathways for transport of pyrethroids were determined in runoff studies conducted at a full-scale test facility in central California, USA. The 6 replicate house lots were typical of front lawns and house fronts of California residential developments and consisted of stucco walls, garage doors, driveways, and residential lawn irrigation sprinkler systems. Each of the 6 lots also included a rainfall simulator to generate artificial rainfall events. Different pyrethroids were applied to 5 surfaces—driveway, garage door and adjacent walls, lawn, lawn perimeter (grass near the house walls), and house walls above grass. The volume of runoff water from each house lot was measured, sampled, and analyzed to determine the amount of pyrethroid mass lost from each surface. Applications to 3 of the house lots were made using the application practices typically used prior to recent label changes, and applications were made to the other 3 house lots according to the revised application procedures. Results from the house lots using the historic application procedures showed that losses of the compounds applied to the driveway and garage door (including the adjacent walls) were 99.75% of total measured runoff losses. The greatest losses were associated with significant rainfall events rather than lawn irrigation events. However, runoff losses were 40 times less using the revised application procedures recently specified on pyrethroid labels. Environ Toxicol Chem 2014;33:52–60. © 2013 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited. PMID:24105831

  17. Comparison of measured and predicted sensible heating and cooling loads for six test buildings

    SciTech Connect

    Burch, D.M.; Walton, G.N.; Licitra, B.A.; Cavanaugh, K.

    1986-06-01

    Hourly sensible heating and cooling loads for six test buildings were predicted using two computer programs, called TARP and EMPS. The predicted loads were compared to corresponding measured loads for winter heating, spring heating, and summer cooling periods. Both computer programs predicted the general trends of the measured data.

  18. Haze, public health and mitigation measures in China: A review of the current evidence for further policy response.

    PubMed

    Gao, Jinghong; Woodward, Alistair; Vardoulakis, Sotiris; Kovats, Sari; Wilkinson, Paul; Li, Liping; Xu, Lei; Li, Jing; Yang, Jun; Li, Jing; Cao, Lina; Liu, Xiaobo; Wu, Haixia; Liu, Qiyong

    2017-02-01

    With rapid economic development, China has been plagued by choking air pollution in recent years, and the frequent occurrence of haze episodes has caused widespread public concern. The purpose of this study is to describe the sources and formation of haze, summarize the mitigation measures in force, review the relationship between haze pollution and public health, and to discuss the challenges, potential research directions and policy options. Haze pollution has both natural and man-made causes, though it is anthropogenic sources that are the major contributors. Accumulation of air pollutants, secondary formation of aerosols, stagnant meteorological conditions, and trans-boundary transportation of pollutants are the principal causes driving the formation and evolution of haze. In China, haze includes gaseous pollutants and fine particles, of which PM2.5 is the dominant component. Short and long-term exposure to haze pollution are associated with a range of negative health outcomes, including respiratory diseases, cardiovascular and cerebrovascular diseases, mental health problems, lung cancer and premature death. China has paid increasing attention to the improvement of air quality, and has introduced action plans and policies to tackle pollution, but many interventions have only temporary effects. There may be fierce resistance from industry groups and some government agencies, and often it is challenging to enforce relevant control measures and laws. We discuss the potential policy options for prevention, the need for wider public dialogue and the implications for scientific research.

  19. Applying quality status criteria to a temperate estuary before and after the mitigation measures to reduce eutrophication symptoms

    NASA Astrophysics Data System (ADS)

    Lillebø, A. I.; Teixeira, H.; Pardal, M. A.; Marques, J. C.

    2007-03-01

    The Mondego estuary is a well-described polyhaline type of transitional water located at the North Atlantic Ocean Ecoregion, where cultural eutrophication progressed over the last decades of the 20th century. Consequently, and due to huge productivity of Ulva spp. Zostera noltii meadows were severely reduced causing the whole ecosystem to become impoverished in terms of macrofaunal abundance, biomass and species richness with a concomitant lowering of secondary production. In 1998, experimental mitigation measures were implemented, via changes in hydrology to increase circulation and diversion of nutrient rich freshwater inflow, to reverse the process in the most affected area of the estuary - its south arm. Thus, the system quality status was assessed before and after 1998, over a ten year period. The OSPAR comprehensive procedure, the first phase of the US-NEEA procedure and the proposed EU-WFD physicochemical status criteria were applied to the data before and after the modifications and all show that the system health has improved. Nonetheless, the annual means of the oxidised forms of nitrogen and of phosphate were not reduced. In fact, applying criteria used in classifying the nutrient levels in transitional waters and the Baltic sea trophic condition, the system has not improved. Meaning that, to look forward to a "higher" quality status, future measures should also consider longer term solutions such as improved agriculture practices in the Mondego River valley through environmental friendly technological solutions that will reduce the nutrient loads to this system.

  20. Soil erosion and mitigation measures on rented and owned fields in Uruguay: the impact of transgenic soya and foreign investors

    NASA Astrophysics Data System (ADS)

    Caon, Lucrezia; Kessler, Aad; Keesstra, Saskia; Cruze, Rick

    2014-05-01

    Governments, companies and individuals with financial capital to invest, are worldwide buying or renting land in developing or third world countries. Uruguay is a developing country whose economy is mainly based on agriculture. Since 2000 many foreigners started to invest in the Uruguayan agricultural sector and to practice intensive large-scale agriculture. The significant presence of foreigners in the country is proven by the fact that almost 360 000 ha out of the 500 000 ha forming the study area were managed by foreigners in 2012. Nowadays farmers have abandoned the traditional crop rotation plan that included pasture to produce grain for export, and transgenic soya (soya RR) became the main crop planted by both foreigners and locals. Besides the high soil erosion rates related to having soya as main crop, planting soya implies the use of glyphosate, a broad-spectrum systemic herbicide leading to important environmental impacts. It is commonly said that foreigners investing in poor countries are exploiting the local natural resources aiming to get the highest possible profit from them. Is this a valid assumption in Uruguay? The purpose of this study was to compare the land management style of foreign and local farmers and to relate it to the soil erosion occurring in the study area. The land tenure (rented or owned fields) and the type of farmer interviewed ("individual farmer" equivalent to L.L.C. or "anonymous society" equivalent to P.L.C.) were taken into consideration during the analysis. Based on what stated by the farmers interviewed, the soil erosion simulations considered the seven most popular crop rotation plans on rented and owned fields, three ideals crop rotation plans, the application of no mitigation measures, and the construction of terraces and conservation buffers. Depending on the crop rotation plan, soils characterized by slope gradients higher than 2 resulted in soil erosion rates higher than the 7 ton/ha/year allowed by law. The highest

  1. A transient liquid crystal thermography technique for gas turbine heat transfer measurements

    NASA Astrophysics Data System (ADS)

    Ekkad, Srinath V.; Han, Je-Chin

    2000-07-01

    This paper presents in detail the transient liquid crystal technique for convective heat transfer measurements. A historical perspective on the active development of liquid crystal techniques for convective heat transfer measurement is also presented. The experimental technique involves using a thermochromic liquid crystal coating on the test surface. The colour change time of the coating at every pixel location on the heat transfer surface during a transient test is measured using an image processing system. The heat transfer coefficients are calculated from the measured time responses of these thermochromic coatings. This technique has been used for turbine blade internal coolant passage heat transfer measurements as well as turbine blade film cooling heat transfer measurements. Results can be obtained on complex geometry surfaces if visually accessible. Some heat transfer results for experiments with jet impingement, internal cooling channels with ribs, flow over simulated TBC spallation, flat plate film cooling, cylindrical leading edge and turbine blade film cooling are presented for demonstration.

  2. Isothermal heat measurements of TBP-nitric acid solutions

    SciTech Connect

    Smith, J.R.; Cavin, W.S.

    1994-12-16

    Net heats of reaction were measured in an isothermal calorimeter for both single phase (organic) and two phase (organic and aqueous) TBP/HNO{sub 3} reacting solutions at temperatures above 100 C. The oxidation rate constant was determined to be 5.4E-4 min{sup {minus}1} at 110 C for an open ``vented`` system as compared to 1.33 E-3 min{sup {minus}1} in the closed system. The heat released per unit material oxidized was also reduced. The oxidation in both phases was found to be first order in nitric acid and pseudo-zero order in butylnitrate and water. The hydrolysis (esterification) rate constant determined by Nichols` (1.33E-3 min{sup {minus}1}) fit the experimental data from this work well. Forced evaporation of the volatile components by the product gases from oxidation resulted in a cooling mechanism which more than balanced the heat from the oxidation reaction in the two-phased systems. Rate expressions were derived and rate constants determined for both the single and two phase systems. An approximating mathematical model was developed to fit the experimental data and to extrapolate beyond the experimental conditions. This model shows that one foot of ``reacting`` 14.3M HNO{sub 3} aqueous phase solution at 121 C will transport sufficient water to the organic phase to replace evaporative losses, maintaining endothermicity, for organic layers up to 12.2 + 6.0 feet deep. If the pressure in a reacting system is allowed to increase due to insufficient venting the temperature of the organic phase would increase in temperature to reach a new equilibrium. The rate of oxidation would increase not only due to the increase in temperature but also from the increased concentration of dissolved HNO{sub 3} reduction products. Another important factor is that the cooling system described in this work becomes less effective as the total pressure increases. These factors probably contributed to the explosion at Tomsk.

  3. Wide-angle sensor measures radiant heat energy in corrosive atmospheres

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Ellipsoidal cavity device measures radiant heat energy over wide incident angles in corrosive atmospheres. The instrument consists of a cavity in copper heat sink sealed with sapphire window to protect thermocouple.

  4. Address to the international workshop on greenhouse gas mitigation, technologies and measures

    SciTech Connect

    Kant, A.

    1996-12-31

    The Netherlands has a long history in combatting natural forces for it`s mere survival and even creation. Around half of the country was not Yet existent around 2000 years ago: it was still below sea level that time. Building dikes and the discovery of eolic energy applied in windmills, allowing to pump water from one side of the dike to the other, are technologies that gradually shaped the country into its current form, a process that continues to materialize till the present day. Water has not always been an enemy of the country. In the Hundred Year War with Spain, during which the country was occupied territory for most of the time, the water was used to drive the Spanish armies from the country. As large parts are well below sea level breaking the dikes resulted in flooding the country which made the armoury of the Spanish army useless. In this way they had to give up the siege of several major Dutch cities that time. These events marked the gradual liberation of the Dutch territory. Consequently, in the discussion on adaption and prevention of the greenhouse effect the Netherlands has a clear stand. The greenhouse effect will occur anyway, even if countries deploy all possible counter measures at once. So their aim is to prevent the occurrence of the greenhouse effect to the highest extent possible, and to protect the most vulnerable areas meanwhile, especially the coastal zones. In order to reach these goals the Dutch government has established a Joint Implementation Experimental Programme in accordance with the provisions made by the Conference of Parties in Berlin (1995).

  5. Feedback system for divertor impurity seeding based on real-time measurements of surface heat flux in the Alcator C-Mod tokamak

    NASA Astrophysics Data System (ADS)

    Brunner, D.; Burke, W.; Kuang, A. Q.; LaBombard, B.; Lipschultz, B.; Wolfe, S.

    2016-02-01

    Mitigation of the intense heat flux to the divertor is one of the outstanding problems in fusion energy. One technique that has shown promise is impurity seeding, i.e., the injection of low-Z gaseous impurities (typically N2 or Ne) to radiate and dissipate the power before it arrives to the divertor target plate. To this end, the Alcator C-Mod team has created a first-of-its-kind feedback system to control the injection of seed gas based on real-time surface heat flux measurements. Surface thermocouples provide real-time measurements of the surface temperature response to the plasma heat flux. The surface temperature measurements are inputted into an analog computer that "solves" the 1-D heat transport equation to deliver accurate, real-time signals of the surface heat flux. The surface heat flux signals are sent to the C-Mod digital plasma control system, which uses a proportional-integral-derivative (PID) algorithm to control the duty cycle demand to a pulse width modulated piezo valve, which in turn controls the injection of gas into the private flux region of the C-Mod divertor. This paper presents the design and implementation of this new feedback system as well as initial results using it to control divertor heat flux.

  6. Feedback system for divertor impurity seeding based on real-time measurements of surface heat flux in the Alcator C-Mod tokamak.

    PubMed

    Brunner, D; Burke, W; Kuang, A Q; LaBombard, B; Lipschultz, B; Wolfe, S

    2016-02-01

    Mitigation of the intense heat flux to the divertor is one of the outstanding problems in fusion energy. One technique that has shown promise is impurity seeding, i.e., the injection of low-Z gaseous impurities (typically N2 or Ne) to radiate and dissipate the power before it arrives to the divertor target plate. To this end, the Alcator C-Mod team has created a first-of-its-kind feedback system to control the injection of seed gas based on real-time surface heat flux measurements. Surface thermocouples provide real-time measurements of the surface temperature response to the plasma heat flux. The surface temperature measurements are inputted into an analog computer that "solves" the 1-D heat transport equation to deliver accurate, real-time signals of the surface heat flux. The surface heat flux signals are sent to the C-Mod digital plasma control system, which uses a proportional-integral-derivative (PID) algorithm to control the duty cycle demand to a pulse width modulated piezo valve, which in turn controls the injection of gas into the private flux region of the C-Mod divertor. This paper presents the design and implementation of this new feedback system as well as initial results using it to control divertor heat flux.

  7. Active region emission measure distributions and implications for nanoflare heating

    SciTech Connect

    Cargill, P. J.

    2014-03-20

    The temperature dependence of the emission measure (EM) in the core of active regions coronal loops is an important diagnostic of heating processes. Observations indicate that EM(T) ∼ T{sup a} below approximately 4 MK, with 2 < a < 5. Zero-dimensional hydrodynamic simulations of nanoflare trains are used to demonstrate the dependence of a on the time between individual nanoflares (T{sub N} ) and the distribution of nanoflare energies. If T{sub N} is greater than a few thousand seconds, a < 3. For smaller values, trains of equally spaced nanoflares cannot account for the observed range of a if the distribution of nanoflare energies is either constant, randomly distributed, or a power law. Power law distributions where there is a delay between consecutive nanoflares proportional to the energy of the second nanoflare do lead to the observed range of a. However, T{sub N} must then be of the order of hundreds to no more than a few thousand seconds. If a nanoflare leads to the relaxation of a stressed coronal field to a near-potential state, the time taken to build up the required magnetic energy is thus too long to account for the EM measurements. Instead, it is suggested that a nanoflare involves the relaxation from one stressed coronal state to another, dissipating only a small fraction of the available magnetic energy. A consequence is that nanoflare energies may be smaller than previously envisioned.

  8. Active Region Emission Measure Distributions and Implications for Nanoflare Heating

    NASA Astrophysics Data System (ADS)

    Cargill, P. J.

    2014-03-01

    The temperature dependence of the emission measure (EM) in the core of active regions coronal loops is an important diagnostic of heating processes. Observations indicate that EM(T) ~ Ta below approximately 4 MK, with 2 < a < 5. Zero-dimensional hydrodynamic simulations of nanoflare trains are used to demonstrate the dependence of a on the time between individual nanoflares (TN ) and the distribution of nanoflare energies. If TN is greater than a few thousand seconds, a < 3. For smaller values, trains of equally spaced nanoflares cannot account for the observed range of a if the distribution of nanoflare energies is either constant, randomly distributed, or a power law. Power law distributions where there is a delay between consecutive nanoflares proportional to the energy of the second nanoflare do lead to the observed range of a. However, TN must then be of the order of hundreds to no more than a few thousand seconds. If a nanoflare leads to the relaxation of a stressed coronal field to a near-potential state, the time taken to build up the required magnetic energy is thus too long to account for the EM measurements. Instead, it is suggested that a nanoflare involves the relaxation from one stressed coronal state to another, dissipating only a small fraction of the available magnetic energy. A consequence is that nanoflare energies may be smaller than previously envisioned.

  9. Estimation of Surface Temperature and Heat Flux by Inverse Heat Transfer Methods Using Internal Temperatures Measured While Radiantly Heating a Carbon/Carbon Specimen up to 1920 F

    NASA Technical Reports Server (NTRS)

    Pizzo, Michelle; Daryabeigi, Kamran; Glass, David

    2015-01-01

    The ability to solve the heat conduction equation is needed when designing materials to be used on vehicles exposed to extremely high temperatures; e.g. vehicles used for atmospheric entry or hypersonic flight. When using test and flight data, computational methods such as finite difference schemes may be used to solve for both the direct heat conduction problem, i.e., solving between internal temperature measurements, and the inverse heat conduction problem, i.e., using the direct solution to march forward in space to the surface of the material to estimate both surface temperature and heat flux. The completed research first discusses the methods used in developing a computational code to solve both the direct and inverse heat transfer problems using one dimensional, centered, implicit finite volume schemes and one dimensional, centered, explicit space marching techniques. The developed code assumed the boundary conditions to be specified time varying temperatures and also considered temperature dependent thermal properties. The completed research then discusses the results of analyzing temperature data measured while radiantly heating a carbon/carbon specimen up to 1920 F. The temperature was measured using thermocouple (TC) plugs (small carbon/carbon material specimens) with four embedded TC plugs inserted into the larger carbon/carbon specimen. The purpose of analyzing the test data was to estimate the surface heat flux and temperature values from the internal temperature measurements using direct and inverse heat transfer methods, thus aiding in the thermal and structural design and analysis of high temperature vehicles.

  10. Ecosystem carbon stock influenced by plantation practice: implications for planting forests as a measure of climate change mitigation.

    PubMed

    Liao, Chengzhang; Luo, Yiqi; Fang, Changming; Li, Bo

    2010-05-27

    Uncertainties remain in the potential of forest plantations to sequestrate carbon (C). We synthesized 86 experimental studies with paired-site design, using a meta-analysis approach, to quantify the differences in ecosystem C pools between plantations and their corresponding adjacent primary and secondary forests (natural forests). Totaled ecosystem C stock in plant and soil pools was 284 Mg C ha(-1) in natural forests and decreased by 28% in plantations. In comparison with natural forests, plantations decreased aboveground net primary production, litterfall, and rate of soil respiration by 11, 34, and 32%, respectively. Fine root biomass, soil C concentration, and soil microbial C concentration decreased respectively by 66, 32, and 29% in plantations relative to natural forests. Soil available N, P and K concentrations were lower by 22, 20 and 26%, respectively, in plantations than in natural forests. The general pattern of decreased ecosystem C pools did not change between two different groups in relation to various factors: stand age (< 25 years vs. > or = 25 years), stand types (broadleaved vs. coniferous and deciduous vs. evergreen), tree species origin (native vs. exotic) of plantations, land-use history (afforestation vs. reforestation) and site preparation for plantations (unburnt vs. burnt), and study regions (tropic vs. temperate). The pattern also held true across geographic regions. Our findings argued against the replacement of natural forests by the plantations as a measure of climate change mitigation.

  11. Ecosystem Carbon Stock Influenced by Plantation Practice: Implications for Planting Forests as a Measure of Climate Change Mitigation

    PubMed Central

    Liao, Chengzhang; Luo, Yiqi; Fang, Changming; Li, Bo

    2010-01-01

    Uncertainties remain in the potential of forest plantations to sequestrate carbon (C). We synthesized 86 experimental studies with paired-site design, using a meta-analysis approach, to quantify the differences in ecosystem C pools between plantations and their corresponding adjacent primary and secondary forests (natural forests). Totaled ecosystem C stock in plant and soil pools was 284 Mg C ha−1 in natural forests and decreased by 28% in plantations. In comparison with natural forests, plantations decreased aboveground net primary production, litterfall, and rate of soil respiration by 11, 34, and 32%, respectively. Fine root biomass, soil C concentration, and soil microbial C concentration decreased respectively by 66, 32, and 29% in plantations relative to natural forests. Soil available N, P and K concentrations were lower by 22, 20 and 26%, respectively, in plantations than in natural forests. The general pattern of decreased ecosystem C pools did not change between two different groups in relation to various factors: stand age (<25 years vs. ≥25 years), stand types (broadleaved vs. coniferous and deciduous vs. evergreen), tree species origin (native vs. exotic) of plantations, land-use history (afforestation vs. reforestation) and site preparation for plantations (unburnt vs. burnt), and study regions (tropic vs. temperate). The pattern also held true across geographic regions. Our findings argued against the replacement of natural forests by the plantations as a measure of climate change mitigation. PMID:20523733

  12. Soil bioengineering measures for disaster mitigation and environmental restoration in Central America: authochtonal cuttings suitability and economic efficiency

    NASA Astrophysics Data System (ADS)

    Petrone, A.; Preti, F.

    2009-04-01

    The use of Soil Bio-Engineering techniques in Developing countries is a relevant issue for Disaster mitigation, environmental restoration and poverty reduction. Research on authochtonal plants suitable for this kind of works and on economic efficiency is essential for the divulgation of this Discipline. The present paper is focused on this two issues related to the realization of various typologies of Soil Bio-engineering works in the Humid tropic of Nicaragua. In the area of Río Blanco, located in the Department of Matagalpa, Soil bio-engineering installations were built in several sites. The particular structures built were: drainages with live fascine mattress, a live palisade, a vegetated live crib wall for riverbank protection, a vegetative covering made of a metallic net and biotextile coupled with a live palisade made of bamboo. In order to evaluate the suitability of the various plants used in the works, monitorings were performed, one in the live palisade alongside an unpaved road and the other on the live crib wall along a riverbank, collecting survival rate and morphological parameters data. Concerning the economic efficiency we proceed to a financial analysis of the works and once the unit price was obtained, we converted the amount in EPP Dollars (Equal Purchasing Power) in order to compare the Nicaraguan context with the Italian one. Among the used species we found that Madero negro (Gliricidia sepium) and Roble macuelizo (Tabebuia rosea) are adequate for Soil-bioengineering measure on slopes while Helequeme (Erythrina fusca) reported a successful behaviour only in the crib wall for riverbank protection. In the comparison of the costs in Nicaragua and in Italy, the unit price reduction for the central American country ranges between 1.5 times (for the vegetative covering) and almost 4 times (for the fascine mattress) if it's used the EPP dollar exchange rate. Thus, a conclusion can be reached with regard to hydrological-risk mitigating actions

  13. Temperature and heat flux measurement techniques for aeroengine fire test: a review

    NASA Astrophysics Data System (ADS)

    Mohammed, I.; Abu Talib, A. R.; Sultan, M. T. H.; Saadon, S.

    2016-10-01

    This review is made of studies whereby some types of fire test measuring instrument were compared based on their mode of operation, sensing ability, temperature resistance and their calibration mode used for aero-engine applications. The study discusses issues affecting temperature and heat flux measurement, methods of measurement, calibration and uncertainties that occur in the fire test. It is found that the temperature and heat flux measurements of the flame from the standard burner need to be corrected and taken into account for radiation heat loss. Methods for temperature and heat flux measurements, as well as uncertainties analysis, were also discussed.

  14. qEMF3, a novel QTL for the early-morning flowering trait from wild rice, Oryza officinalis, to mitigate heat stress damage at flowering in rice, O. sativa.

    PubMed

    Hirabayashi, Hideyuki; Sasaki, Kazuhiro; Kambe, Takashi; Gannaban, Ritchel B; Miras, Monaliza A; Mendioro, Merlyn S; Simon, Eliza V; Lumanglas, Patrick D; Fujita, Daisuke; Takemoto-Kuno, Yoko; Takeuchi, Yoshinobu; Kaji, Ryota; Kondo, Motohiko; Kobayashi, Nobuya; Ogawa, Tsugufumi; Ando, Ikuo; Jagadish, Krishna S V; Ishimaru, Tsutomu

    2015-03-01

    A decline in rice (Oryza sativa L.) production caused by heat stress is one of the biggest concerns resulting from future climate change. Rice spikelets are most susceptible to heat stress at flowering. The early-morning flowering (EMF) trait mitigates heat-induced spikelet sterility at the flowering stage by escaping heat stress during the daytime. We attempted to develop near-isogenic lines (NILs) for EMF in the indica-type genetic background by exploiting the EMF locus from wild rice, O. officinalis (CC genome). A stable quantitative trait locus (QTL) for flower opening time (FOT) was detected on chromosome 3. A QTL was designated as qEMF3 and it shifted FOT by 1.5-2.0 h earlier for cv. Nanjing 11 in temperate Japan and cv. IR64 in the Philippine tropics. NILs for EMF mitigated heat-induced spikelet sterility under elevated temperature conditions completing flower opening before reaching 35°C, a general threshold value leading to spikelet sterility. Quantification of FOT of cultivars popular in the tropics and subtropics did not reveal the EMF trait in any of the cultivars tested, suggesting that qEMF3 has the potential to advance FOT of currently popular cultivars to escape heat stress at flowering under future hotter climates. This is the first report to examine rice with the EMF trait through marker-assisted breeding using wild rice as a genetic resource.

  15. qEMF3, a novel QTL for the early-morning flowering trait from wild rice, Oryza officinalis, to mitigate heat stress damage at flowering in rice, O. sativa

    PubMed Central

    Hirabayashi, Hideyuki; Sasaki, Kazuhiro; Kambe, Takashi; Gannaban, Ritchel B.; Miras, Monaliza A.; Mendioro, Merlyn S.; Simon, Eliza V.; Lumanglas, Patrick D.; Fujita, Daisuke; Takemoto-Kuno, Yoko; Takeuchi, Yoshinobu; Kaji, Ryota; Kondo, Motohiko; Kobayashi, Nobuya; Ogawa, Tsugufumi; Ando, Ikuo; Jagadish, Krishna S. V.; Ishimaru, Tsutomu

    2015-01-01

    A decline in rice (Oryza sativa L.) production caused by heat stress is one of the biggest concerns resulting from future climate change. Rice spikelets are most susceptible to heat stress at flowering. The early-morning flowering (EMF) trait mitigates heat-induced spikelet sterility at the flowering stage by escaping heat stress during the daytime. We attempted to develop near-isogenic lines (NILs) for EMF in the indica-type genetic background by exploiting the EMF locus from wild rice, O. officinalis (CC genome). A stable quantitative trait locus (QTL) for flower opening time (FOT) was detected on chromosome 3. A QTL was designated as qEMF3 and it shifted FOT by 1.5–2.0h earlier for cv. Nanjing 11 in temperate Japan and cv. IR64 in the Philippine tropics. NILs for EMF mitigated heat-induced spikelet sterility under elevated temperature conditions completing flower opening before reaching 35°C, a general threshold value leading to spikelet sterility. Quantification of FOT of cultivars popular in the tropics and subtropics did not reveal the EMF trait in any of the cultivars tested, suggesting that qEMF3 has the potential to advance FOT of currently popular cultivars to escape heat stress at flowering under future hotter climates. This is the first report to examine rice with the EMF trait through marker-assisted breeding using wild rice as a genetic resource. PMID:25534925

  16. Temperature Profile Measurements During Heat Treatment of BSCCO 2212 Coils

    SciTech Connect

    Tollestrup, Alvin; /Fermilab

    2011-04-14

    The temperature profile of two different BSCCO 2212 coils has been analyzed. The profiles are obtained from thermocouples imbedded in the windings during the heat treatment that activates the 2212. The melting and freezing of the 2212 is clearly observed. A model that describes the data and can be used to guide the processing of new coils has been developed. We have obtained the thermal history of two BSCCO coils, one from NHMFL (1) that had 10 layers of 1 mm diameter wire with 0.15 mm insulation and a second coil from OST that had 24 layers with similar insulation and conductor size. Both coils had thermocouples imbedded in the windings and excellent recordings of the temperature over the whole reaction cycle were available for analysis. There are several features that we will address in this note. Measurements have shown that the I{sub c} of the conductor is a sensitive function of its thermal history. This brings up the question of the absolute accuracy of the thermometry in the range around 882 C, the MP of 2212. The reference for the treatment profile is really related to this MP and to small deviations around it. Since the heat of fusion of 2212 is rather large, it generates a clear signal during the melting and cooling transition that automatically generates the relative temperature markers. The physics is the same as the way ice in water maintains an isothermal environment until it is all melted. A related question is the thermal response time of the coil package. The temperature cycles that are being used to optimize strand and small coils can have rapid changes easily implemented whereas a large coil may have such a large thermal time constant that the optimum cycle may not be attainable. A simple analytical model that works well for small solenoids has been developed and an ANSYS (5) program that works for larger coils with more complicated geometry has been set up but will not be discussed in this note.

  17. In situ technique for measuring heat transfer from a power transistor to a boiling liquid

    NASA Astrophysics Data System (ADS)

    Struble, C. L.; Witte, L. C.

    1994-05-01

    A technique for in situ measurement of temperature and heat flux in boiling heat transfer from electronic chips is described. The method was used to obtain accurate partial boiling curves for jet impingement and pool boiling in R-113. While the characteristics of the heat transfer behavior agree with previous data, the data in general lie below data obtained with specialized test chips.

  18. Non-invasive Measures of Core Temperature versus Ingestible Thermistor during Exercise in the Heat

    PubMed Central

    FOGT, DONOVAN L.; HENNING, ANDREA L.; VENABLE, ADAM S.; MCFARLIN, BRIAN K.

    2017-01-01

    The accuracy of core temperature (Tc) thermometry from temporal, tympanic, and oral thermometry devices has been variable during exercise in a hot, humid environment. The purpose of the present study was to cross-validate temporal, two tympanic devices, and oral devices compared to an ingestible thermistor during exercise in a hot, humid environment. Fourteen young, active adults (6 women) completed a graded exercise test until voluntary exhaustion in an environmental chamber (35.5 ± 0.6 °C, 53.9 ± 5.8 % RH). There was no statistical difference in mean temperature between tympanic device 1 and pill-based core temperature (PBTc) measurements across all time points and were positively correlated (0.357; P<0.001). Temperatures of tympanic device 2 were statistically higher than PBTc (37.8 ± 0.7 ºC vs. 37.6 ± 1.0 ºC; respectfully) (P=0.008). At all time points, temperatures for the second tympanic device and PBTc were positively correlated (0.192; P=0.043). Temporal and PBTc values did not differ across time points and were positively correlated (0.262; P=0.005) across all time points. Mean oral temperature was significantly less than mean PBTc across all time points. (37.0 ± 0.4 ºC vs. 37.6 ± 1.0 ºC, respectively) (P<0.001). Across all time points, oral and PBTc were positively correlated (0.262; P=0.010). Tympanic and temporal devices can reflect Tc while exercising in a hot, humid environment. However, care should be taken when selecting the tympanic or temporal measurement device and validation is advised prior to heat illness mitigation in the field. PMID:28344737

  19. Non-invasive Measures of Core Temperature versus Ingestible Thermistor during Exercise in the Heat.

    PubMed

    Fogt, Donovan L; Henning, Andrea L; Venable, Adam S; McFarlin, Brian K

    2017-01-01

    The accuracy of core temperature (Tc) thermometry from temporal, tympanic, and oral thermometry devices has been variable during exercise in a hot, humid environment. The purpose of the present study was to cross-validate temporal, two tympanic devices, and oral devices compared to an ingestible thermistor during exercise in a hot, humid environment. Fourteen young, active adults (6 women) completed a graded exercise test until voluntary exhaustion in an environmental chamber (35.5 ± 0.6 °C, 53.9 ± 5.8 % RH). There was no statistical difference in mean temperature between tympanic device 1 and pill-based core temperature (PBTc) measurements across all time points and were positively correlated (0.357; P<0.001). Temperatures of tympanic device 2 were statistically higher than PBTc (37.8 ± 0.7 ºC vs. 37.6 ± 1.0 ºC; respectfully) (P=0.008). At all time points, temperatures for the second tympanic device and PBTc were positively correlated (0.192; P=0.043). Temporal and PBTc values did not differ across time points and were positively correlated (0.262; P=0.005) across all time points. Mean oral temperature was significantly less than mean PBTc across all time points. (37.0 ± 0.4 ºC vs. 37.6 ± 1.0 ºC, respectively) (P<0.001). Across all time points, oral and PBTc were positively correlated (0.262; P=0.010). Tympanic and temporal devices can reflect Tc while exercising in a hot, humid environment. However, care should be taken when selecting the tympanic or temporal measurement device and validation is advised prior to heat illness mitigation in the field.

  20. Evaluation of Heat Flux Measurement as a New Process Analytical Technology Monitoring Tool in Freeze Drying.

    PubMed

    Vollrath, Ilona; Pauli, Victoria; Friess, Wolfgang; Freitag, Angelika; Hawe, Andrea; Winter, Gerhard

    2017-01-04

    This study investigates the suitability of heat flux measurement as a new technique for monitoring product temperature and critical end points during freeze drying. The heat flux sensor is tightly mounted on the shelf and measures non-invasively (no contact with the product) the heat transferred from shelf to vial. Heat flux data were compared to comparative pressure measurement, thermocouple readings, and Karl Fischer titration as current state of the art monitoring techniques. The whole freeze drying process including freezing (both by ramp freezing and controlled nucleation) and primary and secondary drying was considered. We found that direct measurement of the transferred heat enables more insights into thermodynamics of the freezing process. Furthermore, a vial heat transfer coefficient can be calculated from heat flux data, which ultimately provides a non-invasive method to monitor product temperature throughout primary drying. The end point of primary drying determined by heat flux measurements was in accordance with the one defined by thermocouples. During secondary drying, heat flux measurements could not indicate the progress of drying as monitoring the residual moisture content. In conclusion, heat flux measurements are a promising new non-invasive tool for lyophilization process monitoring and development using energy transfer as a control parameter.

  1. New technique of the local heat flux measurement in combustion chambers of steam boilers

    NASA Astrophysics Data System (ADS)

    Taler, Jan; Taler, Dawid; Sobota, Tomasz; Dzierwa, Piotr

    2011-12-01

    A new method for measurement of local heat flux to water-walls of steam boilers was developed. A flux meter tube was made from an eccentric tube of short length to which two longitudinal fins were attached. These two fins prevent the boiler setting from heating by a thermal radiation from the combustion chamber. The fins are not welded to the adjacent water-wall tubes, so that the temperature distribution in the heat flux meter is not influenced by neighbouring water-wall tubes. The thickness of the heat flux tube wall is larger on the fireside to obtain a greater distance between the thermocouples located inside the wall which increases the accuracy of heat flux determination. Based on the temperature measurements at selected points inside the heat flux meter, the heat flux absorbed by the water-wall, heat transfer coefficient on the inner tube surface and temperature of the water-steam mixture was determined.

  2. Local Measurement of Fuel Energy Deposition and Heat Transfer Environment During Fuel Lifetime Using Controlled Calorimetry

    SciTech Connect

    Don W. Miller; Andrew Kauffmann; Eric Kreidler; Dongxu Li; Hanying Liu; Daniel Mills; Thomas D. Radcliff; Joseph Talnagi

    2001-12-31

    A comprehensive description of the accomplishments of the DOE grant titled, ''Local Measurement of Fuel Energy Deposition and Heat Transfer Environment During Fuel Lifetime using Controlled Calorimetry''.

  3. A novel thin-film temperature and heat-flux microsensor for heat transfer measurements in microchannels.

    PubMed

    Hamadi, David; Garnier, Bertrand; Willaime, Herve; Monti, Fabrice; Peerhossaini, Hassan

    2012-02-07

    Temperature and heat-flux measurement at the microscale for convective heat-transfer studies requires highly precise, minimally intrusive sensors. For this purpose, a new generic temperature and heat-flux sensor was designed, calibrated and tested. The sensor allows measurement of temperature and heat flux distributions along the direction of flow. It is composed of forty gold thermoresistances, 85 nm thick, deposited on both sides of a borosilicate substrate. Their sensitivities are about 37.8 μV K(-1), close to those of a K-type wire thermocouple. Using a thermoelectrical model, temperature biases due to the Joule effect were calculated using the current crossing each thermoresistance and the heat-transfer coefficient. Finally, heat-transfer measurements were performed with deionized water flowing in a straight PDMS microchannel for various Reynolds numbers. The Nusselt number was obtained for microchannels of 50 to 10 μm span. The results were found to be in good agreement with classical Nu-Re macroscopic correlations.

  4. External Heat Transfer Coefficient Measurements on a Surrogate Indirect Inertial Confinement Fusion Target

    DOE PAGES

    Miles, Robin; Havstad, Mark; LeBlanc, Mary; ...

    2015-09-15

    External heat transfer coefficients were measured around a surrogate Indirect inertial confinement fusion (ICF) based on the Laser Inertial Fusion Energy (LIFE) design target to validate thermal models of the LIFE target during flight through a fusion chamber. Results indicate that heat transfer coefficients for this target 25-50 W/m2∙K are consistent with theoretically derived heat transfer coefficients and valid for use in calculation of target heating during flight through a fusion chamber.

  5. External Heat Transfer Coefficient Measurements on a Surrogate Indirect Inertial Confinement Fusion Target

    SciTech Connect

    Miles, Robin; Havstad, Mark; LeBlanc, Mary; Golosker, Ilya; Chang, Allan; Rosso, Paul

    2015-09-15

    External heat transfer coefficients were measured around a surrogate Indirect inertial confinement fusion (ICF) based on the Laser Inertial Fusion Energy (LIFE) design target to validate thermal models of the LIFE target during flight through a fusion chamber. Results indicate that heat transfer coefficients for this target 25-50 W/m2∙K are consistent with theoretically derived heat transfer coefficients and valid for use in calculation of target heating during flight through a fusion chamber.

  6. Measured Heat Transfer in a Transonic Fan Rig at Casing with Implications on Performance

    DTIC Science & Technology

    2015-06-15

    ric grid with cyclic boundary conditions has 201,187 nodes and 28,158 elements which is high resolution for a heat conduction problem with convection ...to data, the probe (see the combination probe in Figure 4) heat transfer effect was modeled as an axisymmetric bump with a different convective heat...On the outside, in three separate regions, a constant convective heat transfer coeffi- cient has been applied using the outside temperature measured by

  7. Measurement-induced operation of two-ion quantum heat machines

    NASA Astrophysics Data System (ADS)

    Chand, Suman; Biswas, Asoka

    2017-03-01

    We show how one can implement a quantum heat machine by using two interacting trapped ions, in presence of a thermal bath. The electronic states of the ions act like a working substance, while the vibrational mode is modelled as the cold bath. The heat exchange with the cold bath is mimicked by the projective measurement of the electronic states. We show how such measurement in a suitable basis can lead to either a quantum heat engine or a refrigerator, which undergoes a quantum Otto cycle. The local magnetic field is adiabatically changed during the heat cycle. The performance of the heat machine depends upon the interaction strength between the ions, the magnetic fields, and the measurement cost. In our model, the coupling to the hot and the cold baths is never switched off in an alternative fashion during the heat cycle, unlike other existing proposals of quantum heat engines. This makes our proposal experimentally realizable using current tapped-ion technology.

  8. Heat Transfer Measurements for a Film Cooled Turbine Vane Cascade

    DTIC Science & Technology

    2008-05-01

    experimental results. We used a transient thermochromic liquid crystal technique to obtain steady state heat transfer data on the mid-span geometry of an... liquid crystal , film cooling, turbine vane 16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE PERSON Douglas R. Thurman a. REPORT U b...used a transient liquid crystal technique to obtain the heat transfer data. Mach number and Reynolds 2 number nearly match real engine

  9. The role of PIXE in the AIRUSE project "testing and development of air quality mitigation measures in Southern Europe"

    NASA Astrophysics Data System (ADS)

    Lucarelli, F.; Chiari, M.; Calzolai, G.; Giannoni, M.; Nava, S.; Udisti, R.; Severi, M.; Querol, X.; Amato, F.; Alves, C.; Eleftheriadis, K.

    2015-11-01

    The European AIRUSE LIFE+ project aims at testing existing and future mitigation measures and developing new strategies for the improvement of air quality in Southern European countries. The project involves public and private institutions of Spain, UK, Portugal, Italy and Greece. PM10 and PM2.5 daily samplings have been scheduled for one year (from January 2013) in four urban sites, Barcelona (Spain), Porto (Portugal), Athens (Greece), and Florence (Italy). The daily data set gives an overall representative picture of the PM composition in these urban sites. The project includes also samplings with hourly resolution for limited periods. Hourly samples give an easier identification of the different aerosol sources due to the capability of tracking rapid changes as the ones occurring in many particulate emissions as well as in atmospheric transport and dilution processes. The role of PIXE technique within the project has been described in this paper. The comparison of data obtained by different techniques (e.g. PIXE, IC and ICP) assured a quality assurance control on the huge quantity of data obtained in the project. PIXE data together with those obtained by other analytical techniques have been used to reconstruct the average aerosol chemical composition and in Positive Matrix Factorization (PMF) analysis to determine the aerosol sources and their impact on PM10 and PM2.5 mass. In particular the high sensitivity of PIXE for all the crustal elements (including Si which is not easily detected by ICP) allows the direct determination of the Saharan dust contribution. Finally, the 1-h resolution data, which can be obtained only by PIXE, confirmed and reinforced the identification of the aerosol sources obtained by the daily concentrations.

  10. Participatory assessment of soil erosion severity and performance of mitigation measured using stakeholders' workshops in Koga catchment, Ethiopia

    NASA Astrophysics Data System (ADS)

    Lakew, Walle; Baartman, Jantiene; Ritsema, Coen

    2016-04-01

    There has been little effort to systematically document the experiences and perceptions of farmers on soil erosion and soil and water conservation (SWC) even though a wealth of SWC knowledge and information exists, and there is a great demand to access it. Sustainable Land Management (SLM) has largely evolved through local traditional practices than being adopted on basis of scientific evidence. This research aimed to document the experiences of farmers on soil erosion and conservation, and to increase awareness and participation of the local community in SWC. Participatory stakeholders' workshops were undertaken at local level focused on experiences and perceptions of farmers. The workshops included group discussion and field monitoring of sheet erosion indicators, profiles of rills and gullies and impacts of SWC strategies. Systematic descriptions of the status of soil erosion, soil fertility and yield were used to assess the performances of SWC strategies. Results show that farmers were aware of the harmful effects of ongoing soil erosion and impacts of mitigation strategies on their farms. Sheet erosion was found to be the most damaging form of erosion while rill damage was critical on cereal cultivated farms on steep slopes. Farmers perceived that the desired impacts of SWC practices were attained in general: runoff and soil loss rates decreased, while soil fertility and production increased. The performance of SWC measures were found to be highly affected by the design quality and management strategies on the farm. Comparatively graded stone-faced soil bunds revealed maximum desired impacts and were liked by farmers whereas all level bunds caused water logging and traditional ditches begun incising and affected production of cereals. Bund maintenance practices were low and also distracted the stability of bunds. This calls for further improvement of design of SWC technologies and their maintenance. Further research should integrate the local knowledge for

  11. Measurement of the Heat Capacity of He-II Under a Heat Current Near the Lambda Transition

    NASA Technical Reports Server (NTRS)

    Harter, Alexa W.; Lee, Richard A. M.; Chui, Talso C. P.; Goodstein, David L.

    2000-01-01

    We present preliminary measurements of the heat capacity of superfluid helium-4 under an applied heat current near the lambda transition. The calorimeter is a standard cylindrical thermal conductivity cell with a 0.6 mm gap between two copper endplates. The sidewall is made of stainless steel. A heat current density in the range of 1 to 4 microW/sq cm is applied through the helium sample while a pulse method is used to measure the heat capacity. Temperature changes are recorded with high-resolution thermometers (HRTs) located on the top and bottom endplates. Corrections are made to the readings of the HRTs to account for the Kapitza boundary resistance and the anomalous Kapitza boundary resistance. After the corrections, both the top and the bottom HRTs. give the same heat capacity values. The heat capacity is found to be much larger than the prediction of recent theories. We also plotted our data on a scaled plot to test the prediction of scaling by the theories. The result and its interpretation will be presented. The cell height was deliberately made to be thin to reduce the effects of gravity. Nonetheless, gravity is expected to have significant effects on the heat capacity data in the temperature range of our measurement. A space experiment would remove this unwanted gravity effect and allow the true physics to be examined. Moreover, in the absence of gravity, a deeper cell can be used allowing HRTs to be mounted on to the sidewall providing direct measurements of the helium temperature, unaffected by the anomalous Kapitza boundary resistance.

  12. Urban population vulnerability to climate extremes: mitigating urban heat through technology and water-sensitive urban design in Australian cities (Invited)

    NASA Astrophysics Data System (ADS)

    Tapper, N. J.

    2013-12-01

    Australia recently endured what was arguably its worst drought in 200 years. The 'Millennium Drought' lasted from 1999 until 2009, producing acute water shortages for several major Australian cities. Towards the end of the drought an extreme heat wave with temperatures approaching 50 C claimed the lives of several hundred people in Melbourne and Adelaide. One outcome of the extreme conditions was that the spectre of climate change and its impacts became very real for most Australians and contributed to the 2007 signing of the Kyoto Protocol by the Australian Government. Issues of extreme heat and water security also led to increased interest in adapting Australian cities to climate change. These concerns ultimately led to the establishment of the Australian Cooperative Research Centre (CRC) for Water Sensitive Cities, a $110 million research initiative to utilise storm water in Australian cities to create cooler and more liveable environments with increased levels of water security. This paper provides an overview of the work being undertaken within the urban climate program of the CRC to identify heat-health vulnerability in our cities and to evaluate the efficacy of irrigated green infrastructure to produce more liveable environments. This papers discusses some of the early research outputs that involve measurement, modelling and remote sensing at a range of scales in Australian cities.

  13. Heat transfer measurements on biconics at incidence in hypersonic high enthalpy air and nitrogen flows

    NASA Technical Reports Server (NTRS)

    Gai, S. L.; Cain, T.; Joe, W. S.; Sandeman, R. J.; Miller, C. G.

    1988-01-01

    Heat transfer rate measurements have been obtained at 0, 5, 15, and 21 deg angles-of-attack for a straight biconic scale model of an aeroassisted orbital vehicle proposed for planetary probe missions. Heat-transfer distributions were measured using palladium thin-film resistance gauges deposited on a glass-ceramic substrate. The windward heat transfer correlations were based on equilibrium flow in the shock layer of the model, although the flow may depart from equilibrium in the flow-field.

  14. Modelling site-specific N2O emission factors from Austrian agricultural soils for targeted mitigation measures (NitroAustria)

    NASA Astrophysics Data System (ADS)

    Amon, Barbara; Zechmeister-Boltenstern, Sophie; Kasper, Martina; Foldal, Cecilie; Schiefer, Jasmin; Kitzler, Barbara; Schwarzl, Bettina; Zethner, Gerhard; Anderl, Michael; Sedy, Katrin; Gaugitsch, Helmut; Dersch, Georg; Baumgarten, Andreas; Haas, Edwin; Kiese, Ralf

    2016-04-01

    community can only profit from NitroAustria, if model developments and results are integrated into the national emission inventory. Trade-offs between different greenhouse gas emissions and other nitrogen losses have to be discussed. The derivation of suitable mitigation options by optimization of common and evaluation of potential management practices for current and future climatic conditions is crucial to minimize threats to the environment while ensuring the long-term productivity and sustainability of agro-ecosystems. From the results gained in NitroAustria we will be able to show potential environmental impacts and propose measures for a policy framework towards climate friendly farming.

  15. Nitrous oxide and nitrate concentration in under-drainage from arable fields subject to diffuse pollution mitigation measures

    NASA Astrophysics Data System (ADS)

    Hama-Aziz, Zanist; Hiscock, Kevin; Adams, Christopher; Reid, Brian

    2016-04-01

    mitigation measure in an agricultural area where high nitrate losses from fields into groundwater or surface water is excessively occurring.

  16. Description of heat flux measurement methods used in hydrocarbon and propellant fuel fires at Sandia.

    SciTech Connect

    Nakos, James Thomas

    2010-12-01

    The purpose of this report is to describe the methods commonly used to measure heat flux in fire applications at Sandia National Laboratories in both hydrocarbon (JP-8 jet fuel, diesel fuel, etc.) and propellant fires. Because these environments are very severe, many commercially available heat flux gauges do not survive the test, so alternative methods had to be developed. Specially built sensors include 'calorimeters' that use a temperature measurement to infer heat flux by use of a model (heat balance on the sensing surface) or by using an inverse heat conduction method. These specialty-built sensors are made rugged so they will survive the environment, so are not optimally designed for ease of use or accuracy. Other methods include radiometers, co-axial thermocouples, directional flame thermometers (DFTs), Sandia 'heat flux gauges', transpiration radiometers, and transverse Seebeck coefficient heat flux gauges. Typical applications are described and pros and cons of each method are listed.

  17. Calorimeter measures high nuclear heating rates and their gradients across a reactor test hole

    NASA Technical Reports Server (NTRS)

    Burwell, D.; Coombe, J. R.; Mc Bride, J.

    1970-01-01

    Pedestal-type calorimeter measures gamma-ray heating rates from 0.5 to 7.0 watts per gram of aluminum. Nuclear heating rate is a function of cylinder temperature change, measured by four chromel-alumel thermocouples attached to the calorimeter, and known thermoconductivity of the tested material.

  18. FOLLOW-UP DURABILITY MEASUREMENTS AND MITIGATION PERFORMANCE IMPROVEMENT TESTS IN 38 EASTERN PENNSYL- VANIA HOUSES HAVING INDOOR REDUCTION SYSTEMS

    EPA Science Inventory

    The report gives results of follow-up tests in 38 difficult- to-mitigate Pennsylvania houses where indoor radon reduction systems had been installed 2 to 4 years earlier. bjectives were to assess system durability, methods for improving performance, and methods for reducing insta...

  19. Heat transfer monitor for measurements of fouling of industrial heat exchangers

    NASA Astrophysics Data System (ADS)

    Panchal, C. B.

    1985-01-01

    A Heat Transfer Monitor (HTM) is a sensitive device that quantifies development of fouling on heat exchanger surfaces in terms of degradation in the heat transfer coefficient as fouling progresses. The Argonne HTM was originally developed by Carnegie-Mellon University for Ocean Thermal Energy Conversion (OTEC) applications and later modified by Argonne National Laboratory. The HTM has been used for the OTEC biofouling and corrosion studies at the Natural Energy Laboratory of Hawaii for the last four years. The major findings from the experimental investigation are: (1) periodic low level of 50 to 70 ppB of chlorination can remove and prevent biofouling; (2) biofouling for deep cold water is negligible; and (3) biofouling control methods for moderately enhanced surfaces are comparable to those for smooth surfaces.

  20. Heat transfer monitor for measurements of fouling of industrial heat exchangers

    SciTech Connect

    Panchal, C.B.

    1985-01-01

    A Heat Transfer Monitor (HTM) is a sensitive device that quantifies development of fouling on heat exchanger surfaces in terms of degradation in the heat transfer coefficient as fouling progresses. The Argonne HTM was originally developed by Carnegie-Mellon University for Ocean Thermal Energy Conversion (OTEC) applications and later modified by Argonne National Laboratory. The HTM has been used for the OTEC biofouling and corrosion studies at the Natural Energy Laboratory of Hawaii for the last four years. The monitor has produced consistent results with an accuracy of about 0.0035 K m/sup 2//kW (0.00002/sup 0/F.h.ft/sup 2//Btu). The major findings from the experimental investigation are: (a) periodic low level of 50 to 70 ppB of chlorination can remove and prevent biofouling, (b) biofouling for deep cold water is negligible, and (c) biofouling control methods for moderately enhanced surfaces are comparable to those for smooth surfaces.

  1. Procedures for measuring the properties of heat-pipe wick materials

    SciTech Connect

    Adkins, D.R.; Dykhuizen, R.C.

    1993-07-01

    Accurate measurements of wick properties must be available to design high-performance beat pipes and to properly interpret results from heat pipe tests. In a program that is aimed at developing heat-pipe receivers for solar-Stirling electric systems, we have recently explored procedures to measure the effective pore radius and permeability of wick materials in their final ``as fabricated`` condition. Measurement techniques are compared in this paper and problems that are frequently encountered in measuring wick properties are discussed.

  2. Measuring the effects of heat wave episodes on the human body's thermal balance

    NASA Astrophysics Data System (ADS)

    Katavoutas, George; Theoharatos, George; Flocas, Helena A.; Asimakopoulos, Dimosthenis N.

    2009-03-01

    During the peak of an extensive heat wave episode on 23-25 July 2007, simultaneous thermophysiological measurements were made in two non-acclimated healthy adults of different sex in a suburban area of Greater Athens, Greece. Based on experimental measurements of mean skin temperature and metabolic heat production, heat fluxes to and from the human body were calculated, and the biometeorological index heat load (HL) produced was determined according to the heat balance equation. Comparing experimental values with those derived from theoretical estimates revealed a great heat stress for both individuals, especially the male, while theoretical values underestimated heat stress. The study also revealed that thermophysiological factors, such as mean skin temperature and metabolic heat production, play an important role in determining heat fluxes patterns in the heat balance equation. The theoretical values of mean skin temperature as derived from an empirical equation may not be appropriate to describe the changes that take place in a non-acclimated individual. Furthermore, the changes in metabolic heat production were significant even for standard activity.

  3. A novel setup for wafer curvature measurement at very high heating rates

    NASA Astrophysics Data System (ADS)

    Islam, T.; Zechner, J.; Bernardoni, M.; Nelhiebel, M.; Pippan, R.

    2017-02-01

    The curvature evolution of a thin film layer stack containing a top Al layer is measured during temperature cycles with very high heating rates. The temperature cycles are generated by means of programmable electrical power pulses applied to miniaturized polysilicon heater systems embedded inside a semiconductor chip and the curvature is measured by a fast wafer curvature measurement setup. Fast temperature cycles with heating duration of 100 ms are created to heat the specimen up to 270 °C providing an average heating rate of 2500 K/s. As a second approach, curvature measurement utilizing laser scanning Doppler vibrometry is also demonstrated which verifies the results obtained from the fast wafer curvature measurement setup. Film stresses calculated from the measured curvature values compare well to literature results, indicating that the new method can be used to measure curvature during fast temperature cycling.

  4. MICRO- AND NANOSCALE MEASUREMENT METHODS FOR PHASE CHANGE HEAT TRANSFER ON PLANAR AND STRUCTURED SURFACES

    SciTech Connect

    Buongiorno, J; Cahill, DG; Hidrovo, CH; Moghaddam, S; Schmidt, AJ; Shi, L

    2014-07-23

    In this opinion piece, we discuss recent advances in experimental methods for characterizing phase change heat transfer. We begin with a survey of techniques for high-resolution measurements of temperature and heat flux at the solid surface and in the working fluid. Next, we focus on diagnostic tools for boiling heat transfer and describe techniques for visualizing the temperature and velocity fields, as well as measurements at the single bubble level. Finally, we discuss techniques to probe the kinetics of vapor formation within a few molecular layers of the interface. We conclude with our outlook for future progress in experimental methods for phase change heat transfer.

  5. Heating of solid earthen material, measuring moisture and resistivity

    DOEpatents

    Heath, William O.; Richardson, Richard L.; Goheen, Steven C.

    1994-01-01

    The present invention includes a method of treating solid earthen material having volatile, semi-volatile, and non-volatile contaminants. Six electrodes are inserted into a region of earthen material to be treated in a substantially equilateral hexagonal arrangement. Six phases of voltages are applied to corresponding electrodes. The voltages are adjusted within a first range of voltages to create multiple current paths between pairs of the electrodes. The current paths are evenly distributed throughout the region defined by the electrodes and therefore uniformly heat the region. The region of earthen material is heated to a temperature sufficient to substantially remove volatile and semi-volatile contaminants by promoting microbial action. This temperature is less than a melting temperature of the earthen material.

  6. Heating of solid earthen material, measuring moisture and resistivity

    DOEpatents

    Heath, W.O.; Richardson, R.L.; Goheen, S.C.

    1994-07-19

    The present invention includes a method of treating solid earthen material having volatile, semi-volatile, and non-volatile contaminants. Six electrodes are inserted into a region of earthen material to be treated in a substantially equilateral hexagonal arrangement. Six phases of voltages are applied to corresponding electrodes. The voltages are adjusted within a first range of voltages to create multiple current paths between pairs of the electrodes. The current paths are evenly distributed throughout the region defined by the electrodes and therefore uniformly heat the region. The region of earthen material is heated to a temperature sufficient to substantially remove volatile and semi-volatile contaminants by promoting microbial action. This temperature is less than a melting temperature of the earthen material. 13 figs.

  7. Wave speed propagation measurements on highly attenuative heated materials

    SciTech Connect

    Moore, David G.; Ober, Curtis C.; Rodacy, Phil J.; Nelson, Ciji L.

    2015-09-19

    Ultrasonic wave propagation decreases as a material is heated. Two factors that can characterize material properties are changes in wave speed and energy loss from interactions within the media. Relatively small variations in velocity and attenuation can detect significant differences in microstructures. This paper discusses an overview of experimental techniques that document the changes within a highly attenuative material as it is either being heated or cooled from 25°C to 90°C. The experimental set-up utilizes ultrasonic probes in a through-transmission configuration. The waveforms are recorded and analyzed during thermal experiments. To complement the ultrasonic data, a Discontinuous-Galerkin Model (DGM) was also created which uses unstructured meshes and documents how waves travel in these anisotropic media. This numerical method solves particle motion travel using partial differential equations and outputs a wave trace per unit time. As a result, both experimental and analytical data are compared and presented.

  8. Quantitative method for measuring heat flux emitted from a cryogenic object

    DOEpatents

    Duncan, R.V.

    1993-03-16

    The present invention is a quantitative method for measuring the total heat flux, and of deriving the total power dissipation, of a heat-fluxing object which includes the steps of placing an electrical noise-emitting heat-fluxing object in a liquid helium bath and measuring the superfluid transition temperature of the bath. The temperature of the liquid helium bath is thereafter reduced until some measurable parameter, such as the electrical noise, exhibited by the heat-fluxing object or a temperature-dependent resistive thin film in intimate contact with the heat-fluxing object, becomes greatly reduced. The temperature of the liquid helum bath is measured at this point. The difference between the superfluid transition temperature of the liquid helium bath surrounding the heat-fluxing object, and the temperature of the liquid helium bath when the electrical noise emitted by the heat-fluxing object becomes greatly reduced, is determined. The total heat flux from the heat-fluxing object is determined as a function of this difference between these temperatures. In certain applications, the technique can be used to optimize thermal design parameters of cryogenic electronics, for example, Josephson junction and infrared sensing devices.

  9. Quantitative method for measuring heat flux emitted from a cryogenic object

    DOEpatents

    Duncan, Robert V.

    1993-01-01

    The present invention is a quantitative method for measuring the total heat flux, and of deriving the total power dissipation, of a heat-fluxing object which includes the steps of placing an electrical noise-emitting heat-fluxing object in a liquid helium bath and measuring the superfluid transition temperature of the bath. The temperature of the liquid helium bath is thereafter reduced until some measurable parameter, such as the electrical noise, exhibited by the heat-fluxing object or a temperature-dependent resistive thin film in intimate contact with the heat-fluxing object, becomes greatly reduced. The temperature of the liquid helum bath is measured at this point. The difference between the superfluid transition temperature of the liquid helium bath surrounding the heat-fluxing object, and the temperature of the liquid helium bath when the electrical noise emitted by the heat-fluxing object becomes greatly reduced, is determined. The total heat flux from the heat-fluxing object is determined as a function of this difference between these temperatures. In certain applications, the technique can be used to optimize thermal design parameters of cryogenic electronics, for example, Josephson junction and infra-red sensing devices.

  10. Measurement and control of heat transfer in steady and unsteady turbulent separated flow

    NASA Astrophysics Data System (ADS)

    Lewis, Douglas J.; Simpson, Roger L.

    1995-06-01

    The turbulence structure of convective heat transfer was studied experimentally in complex three- dimensional and separated turbulent boundary layers. Three test cases whose fluid dynamics have been well documented were examined. In case 1, time resolved surface heat transfer was measured in the nose region of a wing-body junction formed by a wing and a flat plate. Mean, statistical and spectral characteristics of the surface heat transfer are reported. The effects of wing shape were investigated by measuring the surface heat transfer in the nose region of a modified NACA 0020, a streamlined cylinder shape and NACA 0015. The effectiveness of a flow control device to reduce surface heat transfer is reported. In case 2, simultaneous surface heat flux and temperature profiles were measured at 11 locations in the spatially-developing pressure-driven three-dimensional turbulent boundary layer upstream of the wing-body junction. In case 3, simultaneous surface heat flux and temperature profiles were measured at 18 stream-wise locations in a mean 2-dimensional adverse-pressure gradient separating turbulent boundary layer. Mean, statistical and spectral heat flux and temperature data are reported. Mean ejection frequencies, turbulence length scales, inclination angles of the turbulence structure. and coherency between the inner and outer regions of the flow were examined from these results. Several useful correlations between surface heat transfer and velocity are reported.

  11. Aerial measurements of convection cell elements in heated lakes

    NASA Astrophysics Data System (ADS)

    Villa-Aleman, E.; Salaymeh, S. R.; Brown, T. B.; Garrett, A. J.; Nichols, L. S.; Pendergast, M. M.

    2008-03-01

    Power plant-heated lakes are characterized by a temperature gradient in the thermal plume originating at the discharge of the power plant and terminating at the water intake. The maximum water temperature discharged by the power plant into the lake depends on the power generated at the facility and environmental regulations on the temperature of the lake. Besides the observed thermal plume, cloud-like thermal cells (convection cell elements) are also observed on the water surface. The size, shape and temperature of the convection cell elements depends on several parameters such as the lake water temperature, wind speed, surfactants and the depth of the thermocline. The Savannah River National Laboratory (SRNL) and Clemson University are collaborating to determine the applicability of laboratory empirical correlations between surface heat flux and thermal convection intensity. Laboratory experiments at Clemson University have demonstrated a simple relationship between the surface heat flux and the standard deviation of temperature fluctuations. Similar results were observed in the aerial thermal imagery SRNL collected at different locations along the thermal plume and at different elevations. SRNL will present evidence that the results at Clemson University are applicable to cooling lakes.

  12. AERIAL MEASUREMENTS OF CONVECTION CELL ELEMENTS IN HEATED LAKES

    SciTech Connect

    Villa-Aleman, E; Saleem Salaymeh, S; Timothy Brown, T; Alfred Garrett, A; Malcolm Pendergast, M; Linda Nichols, L

    2007-12-19

    Power plant-heated lakes are characterized by a temperature gradient in the thermal plume originating at the discharge of the power plant and terminating at the water intake. The maximum water temperature discharged by the power plant into the lake depends on the power generated at the facility and environmental regulations on the temperature of the lake. Besides the observed thermal plume, cloud-like thermal cells (convection cell elements) are also observed on the water surface. The size, shape and temperature of the convection cell elements depends on several parameters such as the lake water temperature, wind speed, surfactants and the depth of the thermocline. The Savannah River National Laboratory (SRNL) and Clemson University are collaborating to determine the applicability of laboratory empirical correlations between surface heat flux and thermal convection intensity. Laboratory experiments at Clemson University have demonstrated a simple relationship between the surface heat flux and the standard deviation of temperature fluctuations. Similar results were observed in the aerial thermal imagery SRNL collected at different locations along the thermal plume and at different elevations. SRNL will present evidence that the results at Clemson University are applicable to cooling lakes.

  13. Measuring and mitigating inhibition during quantitative real time PCR analysis of viral nucleic acid extracts from large-volume environmental water samples.

    PubMed

    Gibson, K E; Schwab, K J; Spencer, S K; Borchardt, M A

    2012-09-01

    Naturally-occurring inhibitory compounds are a major concern during qPCR and RT-qPCR analysis of environmental samples, particularly large volume water samples. Here, a standardized method for measuring and mitigating sample inhibition in environmental water concentrates is described. Specifically, the method 1) employs a commercially available standard RNA control; 2) defines inhibition by the change in the quantification cycle (C(q)) of the standard RNA control when added to the sample concentrate; and 3) calculates a dilution factor using a mathematical formula applied to the change in C(q) to indicate the specific volume of nuclease-free water necessary to dilute the effect of inhibitors. The standardized inhibition method was applied to 3,193 large-volume water (surface, groundwater, drinking water, agricultural runoff, sewage) concentrates of which 1,074 (34%) were inhibited. Inhibition level was not related to sample volume. Samples collected from the same locations over a one to two year period had widely variable inhibition levels. The proportion of samples that could have been reported as false negatives if inhibition had not been mitigated was between 0.3% and 71%, depending on water source. These findings emphasize the importance of measuring and mitigating inhibition when reporting qPCR results for viral pathogens in environmental waters to minimize the likelihood of reporting false negatives and under-quantifying virus concentration.

  14. The Zebrafish- Danio rerio – Is a Useful Model for Measuring the Effects of Small-molecule Mitigators of Late Effects of Ionizing Irradiation

    PubMed Central

    EPPERLY, MICHAEL W.; BAHARY, NATHAN; QUADER, MUBINA; DEWALD, VALERIE; GREENBERGER, JOEL S.

    2013-01-01

    Background/Aim Use of zebrafish models may decrease the cost of screening new irradiation protectors and mitigators. Materials and Methods Zebrafish (Danio rerio) models were tested for screening water-soluble radiation protectors and mitigators. Irradiation of embryos and monitoring survival, and measuring fibrosis of the caudal musculature of adults allowed for testing of acute and late effects, respectively. Results Incubation of zebrafish embryos either before or after irradiation in ethyl pyruvate (1 mM) increased survival. Irradiation of adults to 15 to 75 Gy, delivered in single-fraction at 13 Gy/min, showed dose-dependent fibrosis at 30 days, quantitated as physiological decrease in swimming tail movement, and histopathological detection of collagen deposition in the dorsal musculature. Continuous administration of small-molecule radioprotector drugs in the water after irradiation reduced both acute and chronic injuries. Conclusion The zebrafish is cost-effective for screening new radiation countermeasures. PMID:23160669

  15. Progress in the measurement of SSME turbine heat flux with plug-type sensors

    NASA Technical Reports Server (NTRS)

    Liebert, Curt H.

    1991-01-01

    Data reduction was completed for tests of plug-type heat flux sensors (gauges) in a turbine blade thermal cycling tester (TBT) that is located at NASA/Marshall Space Flight Center, and a typical gauge is illustrated. This is the first time that heat flux has been measured in a Space Shuttle Main Engine (SSME) Turbopump Turbine environment. The development of the concept for the gauge was performed in a heat flux measurement facility at Lewis. In this facility, transient and steady state absorbed surface heat flux information was obtained from transient temperature measurements taken at points within the gauge. A schematic of the TBT is presented, and plots of the absorbed surface heat flux measured on the three blades tested in the TBT are presented. High quality heat flux values were measured on all three blades. The experiments demonstrated that reliable and durable gauges can be repeatedly fabricated into the airfoils. The experiment heat flux data are being used for verification of SSME analytical stress, boundary layer, and heat transfer design models. Other experimental results and future plans are also presented.

  16. Measuring Heat Flow on the Moon and Mars- The Heat Flow and Physical Properties Package HP-cubed

    NASA Astrophysics Data System (ADS)

    Spohn, T.; Grott, M.; Ho, T.; van Zoest, T.; Kargl, G.; Smrekar, S. E.; Hudson, T. L.

    2010-12-01

    With only two successful heat flow measurements performed on the surface of the Moon to date, the thermal state of the Moon remains poorly constrained. Furthermore, measurements were taken close to the boundary of the Procellarum KREEP terraine, and the obtained values may not be representative for the bulk of the planet. For Mars, no heat flow measurement is yet available. Here we will present the Heat Flow and Physical Properties Package HP-cubed a self-penetrating, robotic heat flow probe. The instrument consists of electrical and temperature sensors that will be emplaced into the lunar subsurface by means of an electro-mechanical hammering mechanism. The instruement is foreseen to penetrate 3-5 m into the planet’s soil and will perform depth resolved measurements, from which the surface planetary heat flow can be directly deduced. The instrument has been pre-developed in two ESA funded precursor studies and has been further developed in the framework of ESA’s ExoMars mission. The current readiness level of the instrument is TRL 5.62 (ESA PDR Apr. 2009) which has been achieved with several Breadboards developed and tested between 2004 and 2009. As no drilling is required to achieve soil penetration, HP-cubed is a relatively lightweight heat flow probe, weighting less than 1800 g. It has been further studied as parts of the discovery proposals Lunette and GEMS and for the proposed Japanese lunar mission SELENE 2 The instrument consists of an electro-mechanic mole, a pay-load compartment, and a tether equipped with temperature sensors. The latter can be actively heated for thermal conductivity measurements. A tiltmeter and acceleraometer will help to track the path of the mole. The payload compartment has room for sensors such as a permittivity probe, a bore-hole camera, and/or a masspectrometer. Following deployment of the instrument, instrument operations will be split into two phases: During the penetration phase soil intrusion is achieved by means of the

  17. Heating of solid earthen material, measuring moisture and resistivity

    DOEpatents

    Heath, William O.; Gauglitz, Phillip A.; Pillay, Gautam; Bergsman, Theresa M.; Eschbach, Eugene A.; Goheen, Steven C.; Richardson, Richard L.; Roberts, Janet S.; Schalla, Ronald

    1996-01-01

    The present invention includes a method of treating solid earthen material having volatile, semi-volatile, and non-volatile contaminants that utilizes electrical energy. A plurality of electrodes are inserted into a region of earthen material to be treated in a selected geometric pattern. Varying phase and voltages configurations are applied to corresponding electrodes to achieve heating, physical phase changes, and the placement of substances within the treatment region. Additionally, treatment mediums can be added to either treat the contamination within the soil or to restrict their mobility.

  18. Heating of solid earthen material, measuring moisture and resistivity

    DOEpatents

    Heath, W.O.; Gauglitz, P.A.; Pillay, G.; Bergsman, T.M.; Eschbach, E.A.; Goheen, S.C.; Richardson, R.L.; Roberts, J.S.; Schalla, R.

    1996-08-13

    The present invention includes a method of treating solid earthen material having volatile, semi-volatile, and non-volatile contaminants that utilizes electrical energy. A plurality of electrodes are inserted into a region of earthen material to be treated in a selected geometric pattern. Varying phase and voltages configurations are applied to corresponding electrodes to achieve heating, physical phase changes, and the placement of substances within the treatment region. Additionally, treatment mediums can be added to either treat the contamination within the soil or to restrict their mobility. 29 figs.

  19. Measurement of Heat Flux and Heat Transfer Coefficient Due to Spray Application for the Die Casting Process

    SciTech Connect

    Sabau, Adrian S

    2007-01-01

    Lubricant spray application experiments were conducted for the die casting process. The heat flux was measured in situ using a differential thermopile sensor for three application techniques. First, the lubricant was applied under a constant flowrate while the nozzle was held in the same position. Second, the lubricant was applied in a pulsed, static manner, in which the nozzle was held over the same surface while it was turned on and off several times. Third, the lubricant was applied in a sweeping manner, in which the nozzle was moved along the die surface while it was held open. The experiments were conducted at several die temperatures and at sweep speeds of 20, 23, and 68 cm/s. The heat flux data, which were obtained with a sensor that was located in the centre of the test plate, were presented and discussed. The sensor can be used to evaluate lubricants, monitor the consistency of die lubrication process, and obtain useful process data, such as surface temperature, heat flux, and heat transfer coefficients. The heat removed from the die surface during lubricant application is necessary for (a) designing the cooling channels in the die, i.e. their size and placement, and (b) performing accurate numerical simulations of the die casting process.

  20. Surface Catalysis and Oxidation on Stagnation Point Heat Flux Measurements in High Enthalpy Arc Jets

    NASA Technical Reports Server (NTRS)

    Nawaz, Anuscheh; Driver, David M.; Terrazas-Salinas

    2013-01-01

    Heat flux sensors are routinely used in arc jet facilities to determine heat transfer rates from plasma plume. The goal of this study is to assess the impact of surface composition changes on these heat flux sensors. Surface compositions can change due to oxidation and material deposition from the arc jet. Systematic surface analyses of the sensors were conducted before and after exposure to plasma. Currently copper is commonly used as surface material. Other surface materials were studied including nickel, constantan gold, platinum and silicon dioxide. The surfaces were exposed to plasma between 0.3 seconds and 3 seconds. Surface changes due to oxidation as well as copper deposition from the arc jets were observed. Results from changes in measured heat flux as a function of surface catalycity is given, along with a first assessment of enthalpy for these measurements. The use of cupric oxide is recommended for future heat flux measurements, due to its consistent surface composition arc jets.

  1. Decay Heat Measurements Using Total Absorption Gamma-ray Spectroscopy

    NASA Astrophysics Data System (ADS)

    Rice, S.; Valencia, E.; Algora, A.; Taín, J. L.; Regan, P. H.; Podolyák, Z.; Agramunt, J.; Gelletly, W.; Nichols, A. L.

    2012-09-01

    A knowledge of the decay heat emitted by thermal neutron-irradiated nuclear fuel is an important factor in ensuring safe reactor design and operation, spent fuel removal from the core, and subsequent storage prior to and after reprocessing, and waste disposal. Decay heat can be readily calculated from the nuclear decay properties of the fission products, actinides and their decay products as generated within the irradiated fuel. Much of the information comes from experiments performed with HPGe detectors, which often underestimate the beta feeding to states at high excitation energies. This inability to detect high-energy gamma emissions effectively results in the derivation of decay schemes that suffer from the pandemonium effect, although such a serious problem can be avoided through application of total absorption γ-ray spectroscopy (TAS). The beta decay of key radionuclei produced as a consequence of the neutron-induced fission of 235U and 239Pu are being re-assessed by means of this spectroscopic technique. A brief synopsis is given of the Valencia-Surrey (BaF2) TAS detector, and their method of operation, calibration and spectral analysis.

  2. Wave speed propagation measurements on highly attenuative heated materials

    DOE PAGES

    Moore, David G.; Ober, Curtis C.; Rodacy, Phil J.; ...

    2015-09-19

    Ultrasonic wave propagation decreases as a material is heated. Two factors that can characterize material properties are changes in wave speed and energy loss from interactions within the media. Relatively small variations in velocity and attenuation can detect significant differences in microstructures. This paper discusses an overview of experimental techniques that document the changes within a highly attenuative material as it is either being heated or cooled from 25°C to 90°C. The experimental set-up utilizes ultrasonic probes in a through-transmission configuration. The waveforms are recorded and analyzed during thermal experiments. To complement the ultrasonic data, a Discontinuous-Galerkin Model (DGM) wasmore » also created which uses unstructured meshes and documents how waves travel in these anisotropic media. This numerical method solves particle motion travel using partial differential equations and outputs a wave trace per unit time. As a result, both experimental and analytical data are compared and presented.« less

  3. Controlled heat flux measurement across a closing nanoscale gap and its comparison to theory

    NASA Astrophysics Data System (ADS)

    Ma, Y.; Ghafari, A.; Budaev, B. V.; Bogy, D. B.

    2016-05-01

    We present here a controlled measurement of heat flux across a closing gap that is initially less than 10 nm wide between two solid surfaces at different temperatures. The measured heat transfer is compared with our published theoretical analyses of this phenomenon that show thermal radiation dominates the heat transfer for gaps wider than about 1-2 nm, but phonon conduction dominates between 1 and 2 nm and contact. The experiments employ a thermal actuator mounted on a rocking base block for coarse positioning that supplies Joule heating to an embedded element to cause thermal expansion of a localized region for less than 10 nm spacing control, together with an embedded near-surface resistive temperature sensor to measure its temperature change due to the heat flux across the gap. The measured results are in general agreement with the theoretical predictions, and they also agree with common sense expectations. This paper not only shows nano-scale heat transfer measurement across a closing gap, it also lends additional strong support to the validity of the referenced theoretical developments. The proposed experimental approach can provide support to design of future devices for nano-scale heat transfer measurement.

  4. Identifiability of electrical and heat transfer parameters using coupled boundary measurements

    NASA Astrophysics Data System (ADS)

    Chang, Yifan

    2017-02-01

    In this paper, we show that a hybrid method using coupled boundary measurements can determine anisotropic electrical conductivity, anisotropic thermal conductivity, and the product of heat capacity and heat density within a bounded domain on the plane uniquely up to a boundary-fixing diffeomorphism.

  5. Sensible Heat Measurements Indicating Depth and Magnitude of Subsurface Soil Water Evaporation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil water evaporation is typically determined by techniques that assume the latent heat flux originates from the soil surface. Here, we describe a new technique for determining in situ soil water evaporation dynamics from fine-scale measurements of soil temperature and thermal properties with heat ...

  6. Heat pulse probe measurements of soil water evaporation in a corn field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Latent heat fluxes from cropped fields consist of soil water evaporation and plant transpiration. It is difficult to accurately separate evapotranspiration into evaporation and transpiration. Heat pulse probes have been used to measure bare field subsurface soil water evaporation, however, the appl...

  7. HEAT OF HYDRATION OF SALTSTONE MIXES-MEASUREMENT BY ISOTHERMAL CALORIMETRY

    SciTech Connect

    Harbour, J; Vickie Williams, V; Tommy Edwards, T

    2007-07-02

    This report provides initial results on the measurement of heat of hydration of Saltstone mixes using isothermal calorimetry. The results were obtained using a recently purchased TAM Air Model 3116 Isothermal Conduction Calorimeter. Heat of hydration is an important property of Saltstone mixes. Greater amounts of heat will increase the temperature of the curing mix in the vaults and limit the processing rate. The heat of hydration also reflects the extent of the hydraulic reactions that turn the fluid mixture into a ''stone like'' solid and consequently impacts performance properties such as permeability. Determining which factors control these reactions, as monitored by the heat of hydration, is an important goal of the variability study. Experiments with mixes of portland cement in water demonstrated that the heats measured by this technique over a seven day period match very well with the literature values of (1) seven day heats of hydration using the standard test method for heat of hydration of hydraulic cement, ASTM C 186-05 and (2) heats of hydration measured using isothermal calorimetry. The heats of hydration of portland cement or blast furnace slag in a Modular Caustic Side Solvent Extraction Unit (MCU) simulant revealed that if the cure temperature is maintained at 25 C, the amount of heat released over a seven day period is roughly 62% less than the heat released by portland cement in water. Furthermore, both the blast furnace slag and the portland cement were found to be equivalent in heat production over the seven day period in MCU. This equivalency is due to the activation of the slag by the greater than 1 Molar free hydroxide ion concentration in the simulant. Results using premix (a blend of 10% cement, 45% blast furnace slag, and 45% fly ash) in MCU, Deliquification, Dissolution and Adjustment (DDA) and Salt Waste Processing Facility (SWPF) simulants reveal that the fly ash had not significantly reacted (undergone hydration reactions) after seven

  8. Inverse estimation of near-field temperature and surface heat flux via single point temperature measurement

    NASA Astrophysics Data System (ADS)

    Wu, Chen-Wu; Shu, Yong-Hua; Xie, Ji-Jia; Jiang, Jian-Zheng; Fan, Jing

    2017-02-01

    A concept was developed to inversely estimate the near-field temperature as well as the surface heat flux for the transient heat conduction problem with boundary condition of the unknown heat flux. The mathematical formula was derived for the inverse estimation of the near-field temperature and surface heat flux via a single point temperature measurement. The experiments were carried out in a vacuum chamber and the theoretically predicted temperatures were justified in specific positions. The inverse estimation principle was validated and the estimation deviation was evaluated for the present configuration.

  9. Testing and Measurement Techniques in Heat Transfer and Combustion.

    DTIC Science & Technology

    1980-09-01

    TURBULENT FLAMES USING THE L2F TECHNIQUE by H.Eickboff and R.Schodl II VELOCITY MEASUREMENT TECHNIQUES IN LIQUID SPRAYS USING LASER DOPPLER VELOCIMETRY by...developed a pyrometer capable of measuring the mean and variance of the fluctuation temperatures in a hot gas stream. Laser -Optical-Velocimetry The...combustion system a temperature P.D.P. has to be built up from a number of measurements . The turbulent environments also dictate the use of broadband laser

  10. Thermodynamics of micellization from heat-capacity measurements.

    PubMed

    Šarac, Bojan; Bešter-Rogač, Marija; Lah, Jurij

    2014-06-23

    Differential scanning calorimetry (DSC), the most important technique for studying the thermodynamics of structural transitions of biological macromolecules, is seldom used in quantitative thermodynamic studies of surfactant micellization/demicellization. The reason for this could be ascribed to an insufficient understanding of the temperature dependence of the heat capacity of surfactant solutions (DSC data) in terms of thermodynamics, which leads to problems with the design of experiments and interpretation of the output signals. We address these issues by careful design of DSC experiments performed with solutions of ionic and nonionic surfactants at various surfactant concentrations, and individual and global mass-action model analysis of the obtained DSC data. Our approach leads to reliable thermodynamic parameters of micellization for all types of surfactants, comparable with those obtained by using isothermal titration calorimetry (ITC). In summary, we demonstrate that DSC can be successfully used as an independent method to obtain temperature-dependent thermodynamic parameters for micellization.

  11. An apparatus for the specific heat measurement of undercooled liquids

    NASA Technical Reports Server (NTRS)

    Ohsaka, K.; Gatewood, J. R.; Trinh, E. H.

    1991-01-01

    This paper describes a drop calorimeter with an electromagnetic levitator that was specifically built for enthalpy measurements of undercooled liquids, including high-melting-point metals. Design diagrams of this device and of a furnace for making a suspended drop are presented together with results of measurements on an aluminum sample.

  12. Thermal conductivity and diffusivity of biomaterials measured with self-heated thermistors

    NASA Astrophysics Data System (ADS)

    Valvano, J. W.; Cochran, J. R.; Diller, K. R.

    1985-05-01

    This paper presents an experimental method to measure the thermal conductivity and thermal diffusivity of biomaterials. Self-heated thermistor probes, inserted into the tissue of interest, are used to deliver heat as well as to monitor the rate of heat removal. An empirical calibration procedure allows accurate thermal-property measurements over a wide range of tissue temperatures. Operation of the instrument in three media with known thermal properties shows the uncertainty of measurements to be about 2%. The reproducibility is 0.5% for the thermal-conductivity measurements and 2% for the thermal-diffusivity measurements. Thermal properties were measured in dog, pig, rabbit, and human tissues. The tissues included kidney, spleen, liver, brain, heart, lung, pancreas, colon cancer, and breast cancer. Thermal properties were measured for 65 separate tissue samples at 3, 10, 17, 23, 30, 37, and 45°C. The results show that the temperature coefficient of biomaterials approximates that of water.

  13. Using a Differential Emission Measure and Density Measurements in an Active Region Core to Test a Steady Heating Model

    NASA Astrophysics Data System (ADS)

    Winebarger, Amy R.; Schmelz, Joan T.; Warren, Harry P.; Saar, Steve H.; Kashyap, Vinay L.

    2011-10-01

    The frequency of heating events in the corona is an important constraint on the coronal heating mechanisms. Observations indicate that the intensities and velocities measured in active region cores are effectively steady, suggesting that heating events occur rapidly enough to keep high-temperature active region loops close to equilibrium. In this paper, we couple observations of active region (AR) 10955 made with the X-Ray Telescope and the EUV Imaging Spectrometer on board Hinode to test a simple steady heating model. First we calculate the differential emission measure (DEM) of the apex region of the loops in the active region core. We find the DEM to be broad and peaked around 3 MK. We then determine the densities in the corresponding footpoint regions. Using potential field extrapolations to approximate the loop lengths and the density-sensitive line ratios to infer the magnitude of the heating, we build a steady heating model for the active region core and find that we can match the general properties of the observed DEM for the temperature range of 6.3 < log T < 6.7. This model, for the first time, accounts for the base pressure, loop length, and distribution of apex temperatures of the core loops. We find that the density-sensitive spectral line intensities and the bulk of the hot emission in the active region core are consistent with steady heating. We also find, however, that the steady heating model cannot address the emission observed at lower temperatures. This emission may be due to foreground or background structures, or may indicate that the heating in the core is more complicated. Different heating scenarios must be tested to determine if they have the same level of agreement.

  14. Investigation on heat transfer between two coaxial cylinders for measurement of thermal accommodation coefficient

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Hiroki; Kanazawa, Kazuaki; Matsuda, Yu; Niimi, Tomohide; Polikarpov, Alexey; Graur, Irina

    2012-06-01

    The heat flux between two coaxial cylinders was measured in the range from the free molecular to the early transitional flow regimes for extraction of the thermal accommodation coefficient using an approximate relation on the pressure dependence of the heat flux. The experimental coaxial cylinders' geometry has been traditionally implemented for the measurement of the thermal accommodation coefficient using the low-pressure method; however, the actual experimental setup was characterized by large temperature difference and large cylinders' radius ratio. Compared to the original low-pressure method, much higher pressure range was applied. In order to verify assumptions in the accommodation coefficient extraction, the heat flux under measurement conditions was simulated numerically by the nonlinear S-model kinetic equation. Very good agreement was found between the measured and the simulated heat flux. The proposed procedure of the thermal accommodation coefficient extraction was discussed in detail and verified. The temperature dependence of the thermal accommodation coefficient was also found.

  15. The Thermal Conductivity Measurements of Solid Samples by Heat Flux Differantial Scanning Calorimetry

    NASA Astrophysics Data System (ADS)

    Kök, M.; Aydoǧdu, Y.

    2007-04-01

    The thermal conductivity of polyvinylchloride (PVC), polysytrene (PS) and polypropylene (PP) were measured by heat flux DSC. Our results are in good agreement with the results observed by different methods.

  16. On-Line Measurement of Heat of Combustion of Gaseous Hydrocarbon Fuel Mixtures

    NASA Technical Reports Server (NTRS)

    Sprinkle, Danny R.; Chaturvedi, Sushil K.; Kheireddine, Ali

    1996-01-01

    A method for the on-line measurement of the heat of combustion of gaseous hydrocarbon fuel mixtures has been developed and tested. The method involves combustion of a test gas with a measured quantity of air to achieve a preset concentration of oxygen in the combustion products. This method involves using a controller which maintains the fuel (gas) volumetric flow rate at a level consistent with the desired oxygen concentration in the combustion products. The heat of combustion is determined form a known correlation with the fuel flow rate. An on-line computer accesses the fuel flow data and displays the heat of combustion measurement at desired time intervals. This technique appears to be especially applicable for measuring heats of combustion of hydrocarbon mixtures of unknown composition such as natural gas.

  17. Comparison of measured and modeled radiation, heat and water vapor fluxes: FIFE pilot study

    NASA Technical Reports Server (NTRS)

    Blad, Blaine L.; Hubbard, Kenneth G.; Verma, Shashi B.; Starks, Patrick; Norman, John M.; Walter-Shea, Elizabeth

    1987-01-01

    The feasibility of using radio frequency receivers to collect data from automated weather stations to model fluxes of latent heat, sensible heat, and radiation using routine weather data collected by automated weather stations was tested and the estimated fluxes were compared with fluxes measured over wheat. The model Cupid was used to model the fluxes. Two or more automated weather stations, interrogated by radio frequency and other means, were utilized to examine some of the climatic variability of the First ISLSCP (International Satellite Land-Surface Climatology Project) Field Experiment (FIFE) site, to measure and model reflected and emitted radiation streams from various locations at the site and to compare modeled latent and sensible heat fluxes with measured values. Some bidirectional reflected and emitted radiation data were collected from 23 locations throughout the FIFE site. Analysis of these data along with analysis of the measured sensible and latent heat fluxes is just beginning.

  18. Influence of stem temperature changes on heat pulse sap flux density measurements.

    PubMed

    Vandegehuchte, Maurits W; Burgess, Stephen S O; Downey, Alec; Steppe, Kathy

    2015-04-01

    While natural spatial temperature gradients between measurement needles have been thoroughly investigated for continuous heat-based sap flow methods, little attention has been given to how natural changes in stem temperature impact heat pulse-based methods through temporal rather than spatial effects. By modelling the theoretical equation for both an ideal instantaneous pulse and a step pulse and applying a finite element model which included actual needle dimensions and wound effects, the influence of a varying stem temperature on heat pulse-based methods was investigated. It was shown that the heat ratio (HR) method was influenced, while for the compensation heat pulse and Tmax methods changes in stem temperatures of up to 0.002 °C s(-1) did not lead to significantly different results. For the HR method, rising stem temperatures during measurements led to lower heat pulse velocity values, while decreasing stem temperatures led to both higher and lower heat pulse velocities, and to imaginary results for high flows. These errors of up to 40% can easily be prevented by including a temperature correction in the data analysis procedure, calculating the slope of the natural temperature change based on the measured temperatures before application of the heat pulse. Results of a greenhouse and outdoor experiment on Pinus pinea L. show the influence of this correction on low and average sap flux densities.

  19. Apparatus development for measuring heat flux in a direct coal-liquefaction preheater

    NASA Astrophysics Data System (ADS)

    Kornosky, R. M.; Perlmutter, M.; Fuchs, W.; Ruether, J. A.

    1982-04-01

    A device is evaluated for determining heat flux in a direct coal liquefaction preheater. The heat fluxmeter determines heat flux from measurements of temperature difference across the preheater tube wall at a given plane perpendicular to the tube axis. Six fluxmeters were installed in a 5.08 m length of nominal 1 1/2 inch diameter, schedule XX pipe enclosed in stacked electric furnaces. Heat flux to a heat transfer fluid flowing through the pipe was measured and compared to values predicted by the fluxmeters. Fair agreement was observed, and the method can be used as an empirical calibration procedure for fluxmeters. A number of apparatus improvements were identified that will be incorporated in the planned experimental program.

  20. Measurements of mixed convective heat transfer to low temperature helium in a horizontal channel

    NASA Technical Reports Server (NTRS)

    Yeroshenko, V. M.; Kuznetsov, Y. V.; Shevchenko, O. A.; Hendricks, R. C.; Daney, D. E.

    1979-01-01

    A horizontal 2.85 m long, 19 mm i.d. stainless steel heated circular channel was employed to measure coefficients of heat transfer to low temperature helium flow. Experimental parameters range from 6.5 to 15 K, from 0.12 to 0.3 MPa at heat fluxes up to 1000 W/m square and Reynolds numbers from 9,000 to 20,000. A significantly nonuniform distribution of heat transfer coefficients over the tube periphery is observed. Difference between temperatures on the upper and lower surfaces of the stainless steel channel wall was found to reach 9 K. It was noted that the highest temperature on the wall outer surface is displaced from its uppermost point. Measurements of local flow temperatures revealed vortical structure of the flow. The displacement of the point with the highest temperature is attributable to the effect of vortices. The relationships for calculating local and averaged coefficients of heat transfer are proposed.

  1. The Atlanta Urban Heat Island Mitigation and Air Quality Modeling Project: How High-Resoution Remote Sensing Data Can Improve Air Quality Models

    NASA Technical Reports Server (NTRS)

    Quattrochi, Dale A.; Estes, Maurice G., Jr.; Crosson, William L.; Khan, Maudood N.

    2006-01-01

    The Atlanta Urban Heat Island and Air Quality Project had its genesis in Project ATLANTA (ATlanta Land use Analysis: Temperature and Air quality) that began in 1996. Project ATLANTA examined how high-spatial resolution thermal remote sensing data could be used to derive better measurements of the Urban Heat Island effect over Atlanta. We have explored how these thermal remote sensing, as well as other imaged datasets, can be used to better characterize the urban landscape for improved air quality modeling over the Atlanta area. For the air quality modeling project, the National Land Cover Dataset and the local scale Landpro99 dataset at 30m spatial resolutions have been used to derive land use/land cover characteristics for input into the MM5 mesoscale meteorological model that is one of the foundations for the Community Multiscale Air Quality (CMAQ) model to assess how these data can improve output from CMAQ. Additionally, land use changes to 2030 have been predicted using a Spatial Growth Model (SGM). SGM simulates growth around a region using population, employment and travel demand forecasts. Air quality modeling simulations were conducted using both current and future land cover. Meteorological modeling simulations indicate a 0.5 C increase in daily maximum air temperatures by 2030. Air quality modeling simulations show substantial differences in relative contributions of individual atmospheric pollutant constituents as a result of land cover change. Enhanced boundary layer mixing over the city tends to offset the increase in ozone concentration expected due to higher surface temperatures as a result of urbanization.

  2. Thin-Film Thermocouple Technology Demonstrated for Reliable Heat Transfer Measurements

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Exploratory work is in progress to apply thin-film thermocouples to localized heat transfer measurements on turbine engine vanes and blades. The emerging thin-film thermocouple technology shows great potential to improve the accuracy of local heat transfer measurements. To verify and master the experimental methodology of thin-film thermocouples, the NASA Lewis Research Center conducted a proof-of-concept experiment in a controlled environment before applying the thin-film sensors to turbine tests.

  3. Laser flash method for measurement of liquid metals heat transfer coefficients

    NASA Astrophysics Data System (ADS)

    Stankus, S. V.; Savchenko, I. V.

    2009-12-01

    New laser flash technique for the measurement of heat transfer coefficients of liquid metals is presented. The thermal diffusivity of the liquid mercury has been studied experimentally over the room temperature range. The thermal conductivity coefficient has been calculated with the use of the reference data on density and heat capacity. Analysis of systematic errors of the measurements has shown that the data error is about 3%. Comparison of the obtained results with data available in publications has proved their reliability.

  4. Compensation of self-heating in the measurement of the dynamic response of a thermoresistive sensor

    SciTech Connect

    Neto, J.S.R.; Deep, G.S.; Freire, R.C.S.; Lima, A.M.N.; Lobo, P.C.

    1997-08-01

    In the experimental determination of the response time of a thermoresistive sensor to a radiation step, one needs to monitor the variation of the ohmic resistance of the sensor with time. This requires passing electrical current through the sensor, which introduces error in the measured response time due to the additional self-heating of the sensor by the electrical current. A theoretical method to eliminate this error is formulated and experimental results are presented. The proposed method also permits experimental determination of the heat capacity (mc) and heat transfer coefficient (UA). The sensitivity analysis of {tau} = mc/UA permits the optimal choice for the resistance measurement currents.

  5. Boiling Heat Transfer Measurements on Highly Conductive Surfaces Using Microscale Heater and Temperature Arrays

    NASA Technical Reports Server (NTRS)

    Kim, J.; Bae, S. W.; Whitten, M. W.; Mullen, J. D.; Quine, R. W.; Kalkur, T. S.

    1999-01-01

    Two systems have been developed to study boiling heat transfer on the microscale. The first system utilizes a 32 x 32 array of diodes to measure the local temperature fluctuations during boiling on a silicon wafer heated from below. The second system utilizes an array of 96 microscale heaters each maintained at constant surface temperature using electronic feedback loops. The power required to keep each heater at constant temperature is measured, enabling the local heat transfer coefficient to be determined. Both of these systems as well as some preliminary results are discussed.

  6. Method of measuring heat influx of a cryogenic transfer system. [Patent application

    DOEpatents

    Niemann, R.C.; Zelipsky, S.A.; Rezmer, R.R.; Smelser, P.

    1980-10-29

    A method is provided for measuring the heat influx of a cryogenic transfer system. A gaseous phase of the cryogen used during normal operation of the system is passed through the system. The gaseous cryogen at the inlet to the system is tempered to duplicate the normal operating temperature of the system inlet. The temperature and mass flow rate of the gaseous cryogen is measured at the outlet of the system, and the heat capacity of the cryogen is determined. The heat influx of the system is then determined from known thermodynamic relationships.

  7. Minimising mortality in endangered raptors due to power lines: the importance of spatial aggregation to optimize the application of mitigation measures.

    PubMed

    Guil, Francisco; Fernández-Olalla, Mariana; Moreno-Opo, Rubén; Mosqueda, Ignacio; Gómez, María Elena; Aranda, Antonio; Arredondo, Angel; Guzmán, José; Oria, Javier; González, Luis Mariano; Margalida, Antoni

    2011-01-01

    Electrocution by power lines is one of the main causes of non-natural mortality in birds of prey. In an area in central Spain, we surveyed 6304 pylons from 333 power lines to determine electrocution rates, environmental and design factors that may influence electrocution and the efficacy of mitigation measures used to minimise electrocution cases. A total of 952 electrocuted raptors, representing 14 different species, were observed. Electrocuted raptors were concentrated in certain areas and the environmental factors associated with increased electrocution events were: greater numbers of prey animals; greater vegetation cover; and shorter distance to roads. The structural elements associated with electrocutions were shorter strings of insulators, one or more phases over the crossarm, cross-shaped design and pylon function. Of the 952 carcasses found, 148 were eagles, including golden eagle (Aquila chrysaetos), Spanish imperial eagle (Aquila adalberti) and Bonelli's eagle (Aquila fasciata). Electrocuted eagles were clustered in smaller areas than other electrocuted raptors. The factors associated with increased eagle electrocution events were: pylons function, shorter strings of insulators, higher slopes surrounding the pylon, and more numerous potential prey animals. Pylons with increased string of insulators had lower raptor electrocution rates than unimproved pylons, although this technique was unsuccessful for eagles. Pylons with cable insulation showed higher electrocution rates than unimproved pylons, both for raptors and eagles, despite this is the most widely used and recommended mitigation measure in several countries. To optimize the application of mitigation measures, our results recommend the substitution of pin-type insulators to suspended ones and elongating the strings of insulators.

  8. Minimising Mortality in Endangered Raptors Due to Power Lines: The Importance of Spatial Aggregation to Optimize the Application of Mitigation Measures

    PubMed Central

    Guil, Francisco; Fernández-Olalla, Mariana; Moreno-Opo, Rubén; Mosqueda, Ignacio; Gómez, María Elena; Aranda, Antonio; Arredondo, Ángel; Guzmán, José; Oria, Javier; González, Luis Mariano; Margalida, Antoni

    2011-01-01

    Electrocution by power lines is one of the main causes of non-natural mortality in birds of prey. In an area in central Spain, we surveyed 6304 pylons from 333 power lines to determine electrocution rates, environmental and design factors that may influence electrocution and the efficacy of mitigation measures used to minimise electrocution cases. A total of 952 electrocuted raptors, representing 14 different species, were observed. Electrocuted raptors were concentrated in certain areas and the environmental factors associated with increased electrocution events were: greater numbers of prey animals; greater vegetation cover; and shorter distance to roads. The structural elements associated with electrocutions were shorter strings of insulators, one or more phases over the crossarm, cross-shaped design and pylon function. Of the 952 carcasses found, 148 were eagles, including golden eagle (Aquila chrysaetos), Spanish imperial eagle (Aquila adalberti) and Bonelli's eagle (Aquila fasciata). Electrocuted eagles were clustered in smaller areas than other electrocuted raptors. The factors associated with increased eagle electrocution events were: pylons function, shorter strings of insulators, higher slopes surrounding the pylon, and more numerous potential prey animals. Pylons with increased string of insulators had lower raptor electrocution rates than unimproved pylons, although this technique was unsuccessful for eagles. Pylons with cable insulation showed higher electrocution rates than unimproved pylons, both for raptors and eagles, despite this is the most widely used and recommended mitigation measure in several countries. To optimize the application of mitigation measures, our results recommend the substitution of pin-type insulators to suspended ones and elongating the strings of insulators. PMID:22140549

  9. Sensitive thermal microsensor with pn junction for heat measurement of a single cell

    NASA Astrophysics Data System (ADS)

    Yamada, Taito; Inomata, Naoki; Ono, Takahito

    2016-02-01

    A sensitive thermal microsensor based on a pn junction diode for heat measurements of biological single cells is developed and evaluated. Using a fabricated device, we demonstrated the heat measurement of a single brown fat cell. The principle of the sensor relies on the temperature dependence of the pn junction diode resistance. This method has a capability of the highly thermal sensitivity by downsizing and the advantage of a simple experimental setup using electrical circuits without any special equipment. To achieve highly sensitive heat measurement of single cells, downsizing of the sensor is necessary to reduce the heat capacity of the sensor itself. The sensor with the pn junction diode can be downsized by microfabrication. A bridge beam structure with the pn junction diode as a thermal sensor is placed in vacuum using a microfludic chip to decrease the heat loss to the surroundings. A temperature coefficient of resistance of 1.4%/K was achieved. The temperature and thermal resolutions of the fabricated device are 1.1 mK and 73.6 nW, respectively. The heat measurements of norepinephrine stimulated and nonstimulated single brown fat cells were demonstrated, and different behaviors in heat generation were observed.

  10. Measuring the Heat Load on the Flight ASTRO-H Soft Xray Spectrometer Dewar

    NASA Technical Reports Server (NTRS)

    DiPirro, M.; Shirron, P.; Yoshida, S.; Kanao, K.; Tsunematsu, S.; Fujimoto, R.; Sneiderman, G.; Kimball, M.; Ezoe, Y.; Ishikawa, K.; Takei, Y.; Mitsuda, K.; Kelley, R.

    2015-01-01

    The Soft Xray Spectrometer (SXS) instrument on-board the ASTRO-H X-ray mission is based on microcalorimeters operating at 50 mK. Low temperature is achieved by use of an adiabatic demagnetization refrigerator (ADR) cyclically operating up to a heat sink at either 1.2 K or 4.5 K. The 1.2 K heat sink is provided by a 40 liter superfluid helium dewar. The parasitic heat to the helium from supports, plumbing, wires, and radiation, and the cyclic heat dumped by the ADR operation determine the liquid helium lifetime. To measure this lifetime we have used various techniques to rapidly achieve thermal equilibrium and then measure the boil-off rate of the helium. We have measured a parasitic heat of 650 microwatts and a cyclic heat of 100 microwatts for a total of 750 microwatts. This closely matches the predicted heat load. Starting with a fill level at launch of more than 33 liters results in a lifetime of greater than 4 years for the liquid helium. The techniques and accuracy for this measurement will be explained in this paper.

  11. Heat transfer and pressure drop measurements in an air/molten salt direct-contact heat exchanger

    SciTech Connect

    Bohn, M.S.

    1988-11-01

    This paper presents a comparison of experimental data with a recently published model of heat exchange in irrigated packed beds. Heat transfer and pressure drop were measured in a 150 mm (ID) column with a 610-mm bed of metal Pall rings. Molten nitrate salt and preheated air were the working fluids with a salt inlet temperature of approximately 440{degree}C and air inlet temperatures of approximately 230{degree}C. A comparison between the experimental data and the heat transfer model is made on the basis of heat transfer from the salt. For the range of air and salt flow rates tested, 0.3 to 1.2 kg/m{sup 2} s air flow and 6 to 18 kg/m{sup 2} s salt flow, the data agree with the model within 22% standard deviation. In addition, a model for the column pressure drop was validated, agreeing with the experimental data within 18% standard deviation over the range of column pressure drop from 40 to 1250 Pa/m. 25 refs., 7 figs., 2 tabs.

  12. The role of the connectivity in the implementation of mitigation measures to reduce the impact of pesticides in the environment under Mediterranean conditions

    NASA Astrophysics Data System (ADS)

    Fernández-Getino García, Ana Patricia; Alonso Prados, Elena; Alonso Prados, José Luis

    2014-05-01

    Regulation 1107/2009 of the European Commission, establishes the procedure and criteria for approval of active substances and authorization of plant protection products in Europe. One of the aspects to be considered is the assessment of the fate and behavior in the environment of pesticides In this assessment a tiered modeling approach is followed according to the models and scenarios developed by the FOrum for the Co-ordination of pesticide fate models and Their USe, (named as FOCUS models/scenarios). They consider different European scenarios to determine the predicted environmental concentration (PEC) in soil, ground water, surface water and sediment at in-field or edge-of-field scales. During the evaluation process, it is frequent to establish different mitigation measures to reduce the impact of pesticides and to ensure an acceptable risk to non-target species. Parallel to this regulatory process, the directive of sustainable use of pesticides (Directive 2009/128/EC) establishes a framework to reduce the impact of use of pesticides where the implementation of mitigation measures to protect aquatic systems and vulnerable areas will play a main role. Therefore, there is a main need to assess how the risk mitigation measures established at field level under regulation 1107/2009 are acting at landscape/catchment level. The characteristics of the climate, relief and soils in Mediterranean region provoke that soil erosion by water is common at different scales. In arable lands soil rates due to inter-rill, rill and gully erosion may exceed 10 ton/ha/year. This process may be modified by human actions. In this scheme, connectivity concept emerges as essential to understand the transfer process of surface water, sediment and micropollutants throughout catchments and the success of the implemented measures for the sustainable management of pesticides at different scales (field, landscape and catchment levels). In this work a review of published monitoring programs of

  13. Measurement and infrared image prediction of a heated exhaust flow

    NASA Astrophysics Data System (ADS)

    Nelson, Edward L.; Mahan, J. Robert; Turk, Jeffrey A.; Birckelbaw, Larry D.; Wardwell, Douglas A.; Hange, Craig E.

    1994-06-01

    The focus of the current research is to numerically predict an infrared image of a jet engine exhaust plume, given field variables such as temperature, pressure, and exhaust plume constituents as a function of spatial position within the plume, and to compare this predicted image directly with measured data. This work is motivated by the need to validate CFD codes through infrared imaging. The technique of reducing the 3D field-variable domain to a 2D infrared image invokes the use of an inverse Monte-Carlo ray trace algorithm and an infrared band model for exhaust gases. This paper describes an experiment in which the above- mentioned field variables were carefully measured. Data from this experiment in the form of velocity plots are shown. The inverse Monte-Carlo ray trace technique is described. Finally, an experimentally obtained infrared image is directly compared to an infrared image predicted from the measured field variables.

  14. Periods found in heat measurements obtained by calorimetry

    SciTech Connect

    Jordan, K.C.

    1984-02-28

    During a span of 640 days, a periodicity of 1.5158 +- 0.0008 days was discovered in successive heater equilibria on Calorimeter No. 127. Measurements were taken at 12-h intervals, with occasional changes of exactly 3 or 6 h in the schedule of measurements. This schedule eliminated all other possible periods except a period of 0.150156 days. Periods of 1.519125 and 1.511283 days were discovered in data on the excess length of day as obtained by the US Naval Observatory over a period of 24 y. These two periods could equally well represent periods of 0.150189 and 0.150112 days, since measurements were obtained only once every 24 h. It is suggested that periods observed in sensitive calorimeters and in length of day data may be related. 1 reference, 6 figures, 5 tables.

  15. Heat Measurements in Electrolytic Metal-Deuteride Experiments

    DTIC Science & Technology

    2015-10-16

    loadings were seen, the excess energy measured was less than the measurement uncertainty. Using Pd in various catalysts (silica, yttria stabilized...we have found that D2 exposure to Pd-filled zeolites and PdNiZrOx catalysts leads to higher temperatures than does H2 exposure. However, we have not...PTFE) structures. At the top, there is a 24.5-mm tall Pd basket for the Pt on Al2O3 recombining catalysts . A leak-free flanged fitting on top

  16. Controlling and measuring quantum transport of heat in trapped-ion crystals.

    PubMed

    Bermudez, A; Bruderer, M; Plenio, M B

    2013-07-26

    Measuring heat flow through nanoscale devices poses formidable practical difficulties as there is no "ampere meter" for heat. We propose to overcome this problem in a chain of trapped ions, where laser cooling the chain edges to different temperatures induces a heat current of local vibrations (vibrons). We show how to efficiently control and measure this current, including fluctuations, by coupling vibrons to internal ion states. This demonstrates that ion crystals provide an ideal platform for studying quantum transport, e.g., through thermal analogues of quantum wires and quantum dots. Notably, ion crystals may give access to measurements of the elusive bosonic fluctuations in heat currents and the onset of Fourier's law. Our results are strongly supported by numerical simulations for a realistic implementation with specific ions and system parameters.

  17. Comparison of measured and modeled radiation, heat and water vapor fluxes: FIFE pilot study

    NASA Technical Reports Server (NTRS)

    Blad, Blaine L.; Verma, Shashi B.; Hubbard, Kenneth G.; Starks, Patrick; Hays, Cynthia; Norman, John M.; Waltershea, Elizabeth

    1988-01-01

    The primary objectives of the 1985 study were to test the feasibility of using radio frequency receivers to collect data from automated weather stations and to evaluate the use of the data collected by the automated weather stations for modeling the fluxes of latent heat, sensible heat, and radiation over wheat. The model Cupid was used to calculate these fluxes which were compared with fluxes of these entities measured using micrometeorological techniques. The primary objectives of the 1986 study were to measure and model reflected and emitted radiation streams at a few locations within the First International Satellite Land-Surface Climatology Project Field Experiment (FIFE) site and to compare modeled and measured latent heat and sensible heat fluxes from the prairie vegetation.

  18. Measurement of Heat Stress: Kiowa and Musketeer Cockpits

    DTIC Science & Technology

    1977-07-01

    aircraft was taken on an operational flight in which 5 "the effect of two configurations, doors closed and doors off,’ on the thermal comfort of the...on the thermal comfort of the pilot could be measured as previously in- dicated by an onboard observer-with pertinent portable equipment. E 5I l

  19. Measuring the Specific Heat of Metals by Cooling

    ERIC Educational Resources Information Center

    Dittrich, William; Minkin, Leonid; Shapovalov, Alexander S.

    2010-01-01

    Three in one? Yes, three standard undergraduate thermodynamics experiments in one, not an oval can of lubricating oil. Previously it has been shown that the PASCO scientific apparatus for measuring coefficients of thermal expansion of metals can also be used to illustrate Newton's law of cooling in the same experiment. Now it will be shown that by…

  20. A new method for simultaneous measurement of convective and radiative heat flux in car underhood applications

    NASA Astrophysics Data System (ADS)

    Khaled, M.; Garnier, B.; Harambat, F.; Peerhossaini, H.

    2010-02-01

    A new experimental technique is presented that allows simultaneous measurement of convective and radiative heat flux in the underhood. The goal is to devise an easily implemented and accurate experimental method for application in the vehicle underhood compartment. The new method is based on a technique for heat-flux measurement developed by the authors (Heat flow (flux) sensors for measurement of convection, conduction and radiation heat flow 27036-2, © Rhopoint Components Ltd, Hurst Green, Oxted, RH8 9AX, UK) that uses several thermocouples in the thickness of a thermal resistive layer (foil heat-flux sensor). The method proposed here uses a pair of these thermocouples with different radiative properties. Measurements validating this novel technique are carried out on a flat plate with a prescribed constant temperature in both natural- and forced-convection flow regimes. The test flat plate is instrumented by this new technique, and also with a different technique that is intrusive but very accurate, used as reference here (Bardon J P and Jarny Y 1994 Procédé et dispositif de mesure transitoire de température et flux surfacique Brevet n°94.011996, 22 February). Discrepancies between the measurements by the two techniques are less than 10% for both convective and radiative heat flux. Error identification and sensitivity analysis of the new method are also presented.

  1. Method and apparatus for real-time measurement of fuel gas compositions and heating values

    DOEpatents

    Zelepouga, Serguei; Pratapas, John M.; Saveliev, Alexei V.; Jangale, Vilas V.

    2016-03-22

    An exemplary embodiment can be an apparatus for real-time, in situ measurement of gas compositions and heating values. The apparatus includes a near infrared sensor for measuring concentrations of hydrocarbons and carbon dioxide, a mid infrared sensor for measuring concentrations of carbon monoxide and a semiconductor based sensor for measuring concentrations of hydrogen gas. A data processor having a computer program for reducing the effects of cross-sensitivities of the sensors to components other than target components of the sensors is also included. Also provided are corresponding or associated methods for real-time, in situ determination of a composition and heating value of a fuel gas.

  2. Flow and heat transfer measurements in a swirl chamber with different outlet geometries

    NASA Astrophysics Data System (ADS)

    Biegger, Christoph; Weigand, Bernhard

    2015-04-01

    In technical applications, an efficient cooling is necessary for high thermal load components such as turbine blades. One potential and promising technique is a swirling tube flow in comparison with an axial flow. The additional circumferential velocity and enhanced turbulent mixing increase the heat transfer. But the complex flow field and heat transfer mechanisms are still under research. Furthermore, the reliability of a swirl chamber regarding different outlet conditions is of great interest for a robust cooling design. Therefore, we investigated the influence of a straight, a tangential and a bend outlet. To gain understanding of the flow phenomena, we measured the velocity field by means of stereo-PIV (particle image velocimetry). We experimentally studied the cooling capability measuring the heat transfer coefficients using thermochromic liquid crystals. For an accurate cooling design, we used the local adiabatic wall temperature as the correct reference temperature for calculating the heat transfer coefficients. We will show the velocity field, the pressure loss and the heat transfer results for realistic Reynolds numbers from 10,000 to 40,000 and for swirl numbers between and . The obtained heat transfer is more than four times higher compared to an axial tube flow. Our measurements indicate that the here investigated outlet redirection has no significant influence on the flow field and the heat transfer coefficients.

  3. Modified Laser Flash Method for Thermal Properties Measurements and the Influence of Heat Convection

    NASA Technical Reports Server (NTRS)

    Lin, Bochuan; Zhu, Shen; Ban, Heng; Li, Chao; Scripa, Rosalia N.; Su, Ching-Hua; Lehoczky, Sandor L.

    2003-01-01

    The study examined the effect of natural convection in applying the modified laser flash method to measure thermal properties of semiconductor melts. Common laser flash method uses a laser pulse to heat one side of a thin circular sample and measures the temperature response of the other side. Thermal diffusivity can be calculations based on a heat conduction analysis. For semiconductor melt, the sample is contained in a specially designed quartz cell with optical windows on both sides. When laser heats the vertical melt surface, the resulting natural convection can introduce errors in calculation based on heat conduction model alone. The effect of natural convection was studied by CFD simulations with experimental verification by temperature measurement. The CFD results indicated that natural convection would decrease the time needed for the rear side to reach its peak temperature, and also decrease the peak temperature slightly in our experimental configuration. Using the experimental data, the calculation using only heat conduction model resulted in a thermal diffusivity value is about 7.7% lower than that from the model with natural convection. Specific heat capacity was about the same, and the difference is within 1.6%, regardless of heat transfer models.

  4. A low-computational-cost inverse heat transfer technique for convective heat transfer measurements in hypersonic flows

    NASA Astrophysics Data System (ADS)

    Avallone, F.; Greco, C. S.; Schrijer, F. F. J.; Cardone, G.

    2015-04-01

    The measurement of the convective wall heat flux in hypersonic flows may be particularly challenging in the presence of high-temperature gradients and when using high-thermal-conductivity materials. In this case, the solution of multidimensional problems is necessary, but it considerably increases the computational cost. In this paper, a low-computational-cost inverse data reduction technique is presented. It uses a recursive least-squares approach in combination with the trust-region-reflective algorithm as optimization procedure. The computational cost is reduced by performing the discrete Fourier transform on the discrete convective heat flux function and by identifying the most relevant coefficients as objects of the optimization algorithm. In the paper, the technique is validated by means of both synthetic data, built in order to reproduce physical conditions, and experimental data, carried out in the Hypersonic Test Facility Delft at Mach 7.5 on two wind tunnel models having different thermal properties.

  5. Development of drought and/or heat tolerant crop varieties, an adaptation approach to mitigate impact of climate change on agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As global climate change becomes inevitable, the sustainability of agricultural production in US and worldwide faces serious threat from extreme weather conditions, such as drought and high temperature (heat wave). Development of drought and/or heat tolerant crop varieties is one of the most effecti...

  6. Space Shuttle Orbiter flight heating rate measurement sensitivity to thermal protection system uncertainties

    NASA Technical Reports Server (NTRS)

    Bradley, P. F.; Throckmorton, D. A.

    1981-01-01

    A study was completed to determine the sensitivity of computed convective heating rates to uncertainties in the thermal protection system thermal model. Those parameters considered were: density, thermal conductivity, and specific heat of both the reusable surface insulation and its coating; coating thickness and emittance; and temperature measurement uncertainty. The assessment used a modified version of the computer program to calculate heating rates from temperature time histories. The original version of the program solves the direct one dimensional heating problem and this modified version of The program is set up to solve the inverse problem. The modified program was used in thermocouple data reduction for shuttle flight data. Both nominal thermal models and altered thermal models were used to determine the necessity for accurate knowledge of thermal protection system's material thermal properties. For many thermal properties, the sensitivity (inaccuracies created in the calculation of convective heating rate by an altered property) was very low.

  7. In vitro measurements of temperature-dependent specific heat of liver tissue.

    PubMed

    Haemmerich, Dieter; dos Santos, Icaro; Schutt, David J; Webster, John G; Mahvi, David M

    2006-03-01

    We measured the specific heat of liver tissue in vitro by uniformly heating liver samples between two electrodes. We insulated the samples by expanded polystyrene, and corrected for heat loss and water loss. The specific heat of the liver is temperature-dependent, and increases by 17% at 83.5 degrees C (p < 0.05), compared to temperatures below 65 degrees C. The average specific heat was 3411 J kg(-1)K(-1) at 25 degrees C, and 4187 J kg(-1)K(-1) at 83.5 degrees C. Water loss from the samples was significant above 70 degrees C, with approximately 20% of reduction in sample mass at 90 degrees C.

  8. Simultaneous Temperature and Velocity Measurements in a Large-Scale, Supersonic, Heated Jet

    NASA Technical Reports Server (NTRS)

    Danehy, P. M.; Magnotti, G.; Bivolaru, D.; Tedder, S.; Cutler, A. D.

    2008-01-01

    Two laser-based measurement techniques have been used to characterize an axisymmetric, combustion-heated supersonic jet issuing into static room air. The dual-pump coherent anti-Stokes Raman spectroscopy (CARS) measurement technique measured temperature and concentration while the interferometric Rayleigh scattering (IRS) method simultaneously measured two components of velocity. This paper reports a preliminary analysis of CARS-IRS temperature and velocity measurements from selected measurement locations. The temperature measurements show that the temperature along the jet axis remains constant while dropping off radially. The velocity measurements show that the nozzle exit velocity fluctuations are about 3% of the maximum velocity in the flow.

  9. Surface heat flow measurements from the East Siberian continental slope and southern Lomonosov Ridge, Arctic Ocean

    NASA Astrophysics Data System (ADS)

    O'Regan, Matt; Preto, Pedro; Stranne, Christian; Jakobsson, Martin; Koshurnikov, Andrey

    2016-05-01

    Surface heat flow data in the Arctic Ocean are needed to assess hydrocarbon and methane hydrate distributions, and provide constraints into the tectonic origins and nature of underlying crust. However, across broad areas of the Arctic, few published measurements exist. This is true for the outer continental shelf and slope of the East Siberian Sea, and the adjoining deep water ridges and basins. Here we present 21 new surface heat flow measurements from this region of the Arctic Ocean. On the Southern Lomonosov Ridge, the average measured heat flow, uncorrected for effects of sedimentation and topography, is 57 ± 4 mW/m2 (n = 4). On the outer continental shelf and slope of the East Siberian Sea (ESS), the average is 57 ± 10 mW/m2 (n = 16). An anomalously high heat flow of 203 ± 28 mW/m2 was measured at a single station in the Herald Canyon. With the exception of this high heat flow, the new data from the ESS are consistent with predictions for thermally equilibrated lithosphere of continental origin that was last affected by thermotectonic processes in the Cretaceous to early Cenozoic. Variability within the data likely arises from differences in radiogenic heat production within the continental crust and overlying sediments. This can be further explored by comparing the data with geophysical constraints on sediment and crustal thicknesses.

  10. Preliminary Results of Heat flow Measurements across the Eastern Flank of the Adare Trough, Antarctica

    NASA Astrophysics Data System (ADS)

    Hong, J. K.; Kim, Y. G.; Jin, Y. K.

    2015-12-01

    Marine heat flow measurement on the ridge is a direct and useful approach to know the current state of thermal regime below the lithosphere. Measurements in ridges located in the Antarctica are practically challenged by harsh conditions such as extensive and moving sea ice cover and stiff seafloor composed of diatomaceous sediments. We planned heat flow measurements across the Adare Trough, north of the Ross Sea, during the recent Korean icebreaker R/V Araon's Antarctic expedition (ANA05B; Dec 12th 2014-Feb 25th 2015) to get thermal information which is a missing piece in terms of geophysical data in this region to describe its asymmetric activity in spreading rate. Finally, we collected information only at three stations across the eastern flank of the Adare Trough over 70 km along with NBP9702 seismic line because of various limitations above. It is a preliminary result that observed heat flow seems significantly higher than estimated one from known magnetic anomaly age using a global age-heat flow curve. In order to conclude some suggestion, we need further studies regarding identification of 'real' heat flow from lithosphere, and increase of the number of data. More heat flow measurements will be carried out again on the eastern flank in the next Araon's Antarctic expedition (tentatively ANA06C; March 2016) to supplement the small number of data.

  11. An instrument for the heat flux measurement from a contour of a surface with uniform temperature

    NASA Astrophysics Data System (ADS)

    Baughn, J. W.; Hoffman, M. A.; Lee, Daehee

    1994-03-01

    An instrument for the measurement of the heat flux distribution along an internal or external contour of a surface with a uniform temperature is described. The main element in this instrument is an electrically heated narrow nickel/chromium ribbon which is mounted flush with, but thermally and electrically insulated from, walls on all sides. The walls are separately heated and are made of a highly conducting material (e.g., aluminum) to ensure a uniform temperature. Differential thermocouples are used to measure the temperature difference between the walls and Ni/Cr ribbon at various positions along the ribbon. The ribbon power is adjusted until the differential temperature is nulled at a particular position on the ribbon. Since conduction along the ribbon is small, the electrical power divided by the sensor area is a direct measure of the surface heat flux at the nulled position. This makes it possible to measure the local time-average heat flux at various positions along a contour of a surface inside a circular duct. The time constant in this application was 13 s. An uncertainty analysis shows that this instrument has an uncertainty of ±3.84% for a convective heat flux on the order of 900 W/m2.

  12. Preliminary results of new surface heat flow measurements in the northern East China Sea

    NASA Astrophysics Data System (ADS)

    Kim, Young-Gyun

    2013-04-01

    Conventional heat flow measurements using a marine heat probe have been rarely carried out in the shallow seas. This is generally because 1) strong bottom-water temperature variation (BTV) which significantly affects temperature distribution in the top few meters of sediments hides the background geothermal gradient generated by conductive heat from deep in Earth, and 2) coarse surficial lithology which prevents the heat probe from being penetrated enough into the sediments is prevalent. In the northern East China Sea, there is few surface heat flow data due to such harsh conditions. The sea experiences seasonal flux change of Kuroshio and Taiwan Warm currents and large amount of sediment discharge from Yangtze River. New heat flow measurements using a Ewing-type heat probe were made at 11 sites with water depths of 57-120 mbsl in December 2012. For the successive penetration of the probe, areas of the finer surficial lithology were carefully chosen as target sites based on core samples using a gravity corer as well as Chirp survey results. Also, length and weight of the heat probe were adjusted to 3 meter with 7 thermistors and ~450 kg, respectively. As a result, the heat probe nearly vertically penetrated up to its full length into the sediments. Observed temperatures at depths are not fitted into a linear line, and show overall inversion with local maximum value at the middle depths. These are clear evidences of temperature disturbance by BTV. Due to lack of information, BTV is roughly approximated based on available bottom-water temperature data in the vicinity of the study area. After removal of BTV effects, the observed temperatures are nearly aligned into a line, indicating that conductive cooling is dominant heat transfer process in this region. Accordingly, the background geothermal gradient is estimated as 20-30 mK/m comparable with results from wells around the study area.

  13. Metallized Gelled Propellants: Oxygen/RP-1/Aluminum Rocket Engine Calorimeter Heat Transfer Measurements and Analysis

    NASA Technical Reports Server (NTRS)

    Palaszewski, Bryan

    1997-01-01

    A set of analyses was conducted to determine the heat transfer characteristics of metallized gelled liquid propellants in a rocket engine. The analyses used the data from experiments conducted with a small 30- to 40-lbf thrust engine composed of a modular injector, igniter, chamber and nozzle. The fuels used were traditional liquid RP-1 and gelled RP-1 with 0-wt %, 5-wt%, and 55-wt% loadings of aluminum with silicon dioxide gellant, and gaseous oxygen as the oxidizer. Heat transfer was computed based on measurements using calorimeter rocket chamber and nozzle hardware with a total of 31 cooling channels. A gelled fuel coating formed in the 0-, 5- and 55-wt% engines, and the coating was composed of unburned gelled fuel and partially combusted RP-1. The coating caused a large decrease in calorimeter engine heat flux in the last half of the chamber for the 0- and 5-wt% RP-1/Al. This heat flux reduction effect was analyzed by comparing engine runs and the changes in the heat flux during a run as well as from run to run. Heat transfer and time-dependent heat flux analyses and interpretations are provided. The 5- and 55-wt% RP-1/Al fueled engines had the highest chamber heat fluxes, with the 5-wt% fuel having the highest throat flux. This result is counter to the predicted result, where the 55 wt% fuel has the highest combustion and throat temperature, and therefore implies that it would deliver the highest throat heat flux. The 5-wt% RP-1/Al produced the most influence on the engine heat transfer and the heat flux reduction was caused by the formation of a gelled propellant layer in the chamber and nozzle.

  14. Measurements of heat transfer coefficients and friction factors in passages rib-roughened on all walls

    SciTech Connect

    Taslim, M.E.; Li, T.; Spring, S.D.

    1998-07-01

    A liquid crystal technique was used to measure heat transfer coefficients in twelve test sections with square and trapezoidal cross-sectional areas representing blade midchord cooling cavities in a modern gas turbine. Full-length ribs were configured on suction side as well as pressure side walls while half-length ribs were mounted on partition walls between adjacent cooling cavities. Ribs were in staggered arrangements with a nominal blockage ratio of 22% and an angle of attack to the mainstream flow, {alpha}, of 90 deg. Heat transfer measurements were performed on the roughened walls with full-length as well as half-length ribs. Nusselt numbers, friction factors, and thermal performances of all geometries are compared. The most important conclusion of this study is that the roughening of the partition walls enhances the heat transfer coefficients on those walls but, more importantly, enhances heat transfer coefficients on the primary walls considerably.

  15. The direct heat measurement of mechanical energy storage metal-organic frameworks.

    PubMed

    Rodriguez, Julien; Beurroies, Isabelle; Loiseau, Thierry; Denoyel, Renaud; Llewellyn, Philip L

    2015-04-07

    In any process, the heat exchanged is an essential property required in its development. Whilst the work related to structural transitions of some flexible metal-organic frameworks (MOFs) has been quantified and linked with potential applications such as molecular springs or shock absorbers, the heat related to such transitions has never been directly measured. This has now been carried out with MIL-53(Al) using specifically devised calorimetry experiments. We project the importance of these heats in devices such as molecular springs or dampers.

  16. Measurement of convective heat transfer coefficient for a horizontal cylinder rotating in quiescent air

    SciTech Connect

    Oezerdem, B.

    2000-04-01

    Heat transfer from a rotating cylinder is one of the problems, which is drawing attention due to its wide range of engineering applications. The present paper deals with convective heat transfer from a horizontal cylinder rotating in quiescent air, experimentally. The average convective heat transfer coefficients have been measured by using radiation pyrometer, which offers a new method. According to the experimental results, a correlation in terms of the average Nusselt number and rotating Reynolds number has been established. The average Nusselt number increased with an increase in the rotating speed. Comparison of the results, with previous studies, have been showed a good agreement with each other.

  17. Development of a new device to measure local heat exchange by evaporation and convection.

    PubMed

    Kakitsuba, N; Katsuura, T

    1992-06-01

    According to the principles of heat and mass transfer, the rate of local heat exchange by convection (C) and local heat loss by evaporation (E) can be estimated if temperature and vapor concentration profiles in the boundary layer are measured. In addition, temperature (Ts) and vapor concentration (rho s) at the surface may be predicted from the measured profiles. On this basis, a new device was developed to measure parabolic profiles by incorporating three relative humidity sensors coupled with thermistors into its probe. It has been evaluated from various tests including human experiments. The results showed that the device, with humidity sensors arranged perpendicular to the surface, could estimate C, E, Ts, and rho s in closer agreement with direct measurements when compared with the conventional gradient method. This confirmed that our method had clear advantages over the conventional gradient method under laminar air flow conditions.

  18. Specific Heat Capacity Measurement of Single-Crystalline Silicon as New Reference Material

    NASA Astrophysics Data System (ADS)

    Abe, Haruka; Kato, Hideyuki; Baba, Tetsuya

    2011-11-01

    We started to develop a new certified reference material for specific heat capacity measurement using a new type of cryogenic adiabatic calorimeter, applying a pulse-tube cryocooler in the temperature range from 50 to 350 K. A candidate certified reference material is single-crystalline silicon. To check the performance of the equipment, we measured the specific heat capacity of NIST SRM720, a type of synthetic sapphire. The relative expanded uncertainty of the measurement was estimated to be 0.65% at 350 K and 8.2% at 50 K, and the certified value of SRM720 was within the limits of uncertainty. In the next step, we measured the temperature dependence of the specific heat capacity of single-crystalline silicon. The result was compared with some reference data, and good agreement within 0.6% residual was found.

  19. An optical fiber sensing technique for temperature distribution measurements in microwave heating

    NASA Astrophysics Data System (ADS)

    Wada, Daichi; Sugiyama, Jun-ichi; Zushi, Hiroaki; Murayama, Hideaki

    2015-08-01

    We introduce an optical fiber sensing technique that can measure the temperature distributions along a fiber during microwave heating. We used a long-length fiber Bragg grating (FBG) as an electromagnetic-immune sensor and interrogated temperature distributions along the FBG by an optical frequency domain reflectometry. Water in a glass tube with a length of 820 mm was heated in a microwave oven, and its temperature distribution along the glass tube was measured using the sensing system. The temperature distribution was obtained in 5 mm intervals. Infrared radiometry was also used to compare the temperature measurement results. Time and spatial variations of the temperature distribution profiles were monitored for several microwave input powers. The results clearly depict inhomogeneous temperature profiles. The applicability and effectiveness of the optical fiber distributed measurement technique in microwave heating are demonstrated.

  20. Measuring Joule heating and strain induced by electrical current with Moire interferometry

    SciTech Connect

    Chen Bicheng; Basaran, Cemal

    2011-04-01

    This study proposes a new method to locate and measure the temperature of the hot spots caused by Joule Heating by measuring the free thermal expansion in-plane strain. It is demonstrated that the hotspot caused by the Joule heating in a thin metal film/plate structure can be measured by Phase shifting Moire interferometry with continuous wavelet transform (PSMI/CWT) at the microscopic scale. A demonstration on a copper film is conducted to verify the theory under different current densities. A correlation between the current density and strain in two orthogonal directions (one in the direction of the current flow) is proposed. The method can also be used for the measurement of the Joule heating in the microscopic solid structures in the electronic packaging devices. It is shown that a linear relationship exists between current density squared and normal strains.

  1. Equation of State Measurements of Dense Plasmas Heated by Laser Accelerated MeV Protons

    NASA Astrophysics Data System (ADS)

    Dyer, Gilliss; Bernstein, Aaron; Cho, Byoung-Ick; Grigsby, Will; Dalton, Allen; Shepherd, Ronnie; Ping, Yuan; Chen, Hui; Widmann, Klaus; Ozterhoz, Jens; Ditmire, Todd

    2008-04-01

    Using a fast proton beam generated with an ultra intense laser we have generated and measured the equation of state of solid density plasma at temperatures near 20 eV, a regime in which there have been few previous experimental measurements. The laser accelerated a directional, short pulse of MeV protons, which isochorically heated a solid slab of aluminum. Using two simultaneous, temporally resolved measurements we observed the thermal emission and expansion of the heated foil with picosecond time resolution. With these data we were able to confirm, to within 10%, the SESAME equation-of-state table in this dense plasma region.

  2. Adaptation to high temperature mitigates the impact of water deficit during combined heat and drought stress in C3 sunflower and C4 maize varieties with contrasting drought tolerance.

    PubMed

    Killi, Dilek; Bussotti, Filippo; Raschi, Antonio; Haworth, Matthew

    2017-02-01

    Heat and drought stress frequently occur together, however, their impact on plant growth and photosynthesis (PN ) is unclear. The frequency, duration and severity of heat and drought stress events are predicted to increase in the future, having severe implications for agricultural productivity and food security. To assess the impact on plant gas exchange, physiology and morphology we grew drought tolerant and sensitive varieties of C3 sunflower (Helianthus annuus) and C4 maize (Zea mays) under conditions of elevated temperature for 4 weeks prior to the imposition of water deficit. The negative impact of temperature on PN was most apparent in sunflower. The drought tolerant sunflower retained ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) activity under heat stress to a greater extent than its drought sensitive counterpart. Maize exhibited no varietal difference in response to increased temperature. In contrast to previous studies, where a sudden rise in temperature induced an increase in stomatal conductance (Gs ), we observed no change or a reduction in Gs with elevated temperature, which alongside lower leaf area mitigated the impact of drought at the higher temperature. The drought tolerant sunflower and maize varieties exhibited greater investment in root-systems, allowing greater uptake of the available soil water. Elevated temperatures associated with heat-waves will have profound negative impacts on crop growth in both sunflower and maize, but the deleterious effect on PN was less apparent in the drought tolerant sunflower and both maize varieties. As C4 plants generally exhibit water use efficiency (WUE) and resistance to heat stress, selection on the basis of tolerance to heat and drought stress would be more beneficial to the yields of C3 crops cultivated in drought prone semi-arid regions.

  3. Measurement of frost characteristics on heat exchanger fins. Part 2: Data and analysis

    SciTech Connect

    Chen, H.; Thomas, L.; Besant, R.W.

    1999-07-01

    Part 1 of this paper described the frost growth test facility and instrumentation. In Part 2, results are presented for typical operating conditions with frost growth on heat exchanger fins. Typical data are presented for frost height distributions on fins, increase in pressure loss for airflow through a finned test section, frost mass accumulation on fins, and heat rate. Special attention is given to the uncertainty in each of these measurements and calculations.

  4. The Measurement of the Specific Latent Heat of Fusion of Ice: Two Improved Methods.

    ERIC Educational Resources Information Center

    Mak, S. Y.; Chun, C. K. W.

    2000-01-01

    Suggests two methods for measuring the specific latent heat of ice fusion for high school physics laboratories. The first method is an ice calorimeter which is made from simple materials. The second method improves the thermal contact and allows for a more accurate measurement. Lists instructions for both methods. (Author/YDS)

  5. Soil-water evaporation dynamics determined with measurement of sensible heat transfer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil-water evaporation is important in both the hydrologic cycle and the surface energy balance. Yet, routine measurements are unable to capture rapidly shifting near-surface soil heat and water processes involved in evaporation. Recent improvements for fine-scale measurement of soil thermal propert...

  6. Alternative energy balances for Bulgaria to mitigate climate change

    SciTech Connect

    Christov, C.

    1996-09-01

    Alternative energy balances aimed to mitigate greenhouse gas (GHG) emissions are developed as alternatives to the baseline energy balance. The section of mitigation options is based on the results of the GHG emission inventory for the 1987-1992 period. The energy sector is the main contributor to the total CO{sub 2} emissions of Bulgaria. Stationary combustion for heat and electricity production as well as direct end-use combustion amounts to 80% of the total emissions. The parts of the energy network that could have the biggest influence on GHG emission reduction are identified. The potential effects of the following mitigation measures are discussed: rehabilitation of the combustion facilities currently in operation; repowering to natural gas; reduction of losses in thermal and electrical transmission and distribution networks; penetration of new combustion technologies; tariff structure improvement; renewable sources for electricity and heat production; waste-heat utilization; and supply of households with natural gas to substitute for electricity in space heating and cooking. The total available and the achievable potentials are estimated and the implementation barriers are discussed. 3 refs.

  7. High geothermal heat flux measured below the West Antarctic Ice Sheet

    PubMed Central

    Fisher, Andrew T.; Mankoff, Kenneth D.; Tulaczyk, Slawek M.; Tyler, Scott W.; Foley, Neil

    2015-01-01

    The geothermal heat flux is a critical thermal boundary condition that influences the melting, flow, and mass balance of ice sheets, but measurements of this parameter are difficult to make in ice-covered regions. We report the first direct measurement of geothermal heat flux into the base of the West Antarctic Ice Sheet (WAIS), below Subglacial Lake Whillans, determined from the thermal gradient and the thermal conductivity of sediment under the lake. The heat flux at this site is 285 ± 80 mW/m2, significantly higher than the continental and regional averages estimated for this site using regional geophysical and glaciological models. Independent temperature measurements in the ice indicate an upward heat flux through the WAIS of 105 ± 13 mW/m2. The difference between these heat flux values could contribute to basal melting and/or be advected from Subglacial Lake Whillans by flowing water. The high geothermal heat flux may help to explain why ice streams and subglacial lakes are so abundant and dynamic in this region. PMID:26601210

  8. Heat transport measurements in turbulent rotating Rayleigh-Bénard convection.

    PubMed

    Liu, Yuanming; Ecke, Robert E

    2009-09-01

    We present experimental heat transport measurements of turbulent Rayleigh-Bénard convection with rotation about a vertical axis. The fluid, water with a Prandtl number (sigma) of about 6, was confined in a cell with a square cross section of 7.3 x 7.3 cm2 and a height of 9.4 cm. Heat transport was measured for Rayleigh numbers 2 x 10(5)heat transport, the Nusselt number, at fixed dimensional rotation rate OmegaD, at fixed Ra varying Ta, at fixed Ta varying Ra, and at fixed Rossby number Ro. The scaling of heat transport in the range of 10(7) to about 10(9) is roughly 0.29 with a Ro-dependent coefficient or equivalently is also well fit by a combination of power laws of the form a Ra1/5+b Ra1/3. The range of Ra is not sufficient to differentiate single power law or combined power-law scaling. The data are roughly consistent with an assumption that the enhancement of heat transport owing to rotation is proportional to the number of vortical structures penetrating the boundary layer. We also compare indirect measures of thermal and Ekman boundary layer thicknesses to assess their potential role in controlling heat transport in different regimes of Ra and Ta.

  9. High geothermal heat flux measured below the West Antarctic Ice Sheet.

    PubMed

    Fisher, Andrew T; Mankoff, Kenneth D; Tulaczyk, Slawek M; Tyler, Scott W; Foley, Neil

    2015-07-01

    The geothermal heat flux is a critical thermal boundary condition that influences the melting, flow, and mass balance of ice sheets, but measurements of this parameter are difficult to make in ice-covered regions. We report the first direct measurement of geothermal heat flux into the base of the West Antarctic Ice Sheet (WAIS), below Subglacial Lake Whillans, determined from the thermal gradient and the thermal conductivity of sediment under the lake. The heat flux at this site is 285 ± 80 mW/m(2), significantly higher than the continental and regional averages estimated for this site using regional geophysical and glaciological models. Independent temperature measurements in the ice indicate an upward heat flux through the WAIS of 105 ± 13 mW/m(2). The difference between these heat flux values could contribute to basal melting and/or be advected from Subglacial Lake Whillans by flowing water. The high geothermal heat flux may help to explain why ice streams and subglacial lakes are so abundant and dynamic in this region.

  10. Measurement of Latent Heat of Melting of Thermal Storage Materials for Dynamic Type Ice Thermal Storage

    NASA Astrophysics Data System (ADS)

    Sawada, Hisashi; Okada, Masashi; Nakagawa, Shinji

    In order to measure the latent heat of melting of ice slurries with various solute concentrations, an adiabatic calorimeter was constructed. Ice slurries were made from each aqueous solution of ethanol, ethylene glycol and silane coupling agent. The latent heat of melting of ice made from tap water was measured with the present calorimeter and the uncertainty of the result was one percent. Ice slurries were made both by mixing ice particles made from water with each aqueous solution and by freezing each aqueous solution with stirring in a vessel. The latent heat of melting of these ice slurries was measured with various concentrations of solution. The latent heat of melting decreased as the solute concentration or the freezing point depression increased. The latent heat of ice slurries made from ethanol or ethylene glycol aqueous solution agreed with that of ice made from pure water known already. The latent heat of melting of ice slurries made from silane coupling agent aqueous solution got smaller than that of ice made from pure water as the freezing point depression increased.

  11. Artificial Neural Networks-Based Software for Measuring Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters.

    PubMed

    Liu, Zhijian; Liu, Kejun; Li, Hao; Zhang, Xinyu; Jin, Guangya; Cheng, Kewei

    2015-01-01

    Measurements of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, conventional measurement requires expensive detection devices and undergoes a series of complicated procedures. To simplify the measurement and reduce the cost, software based on artificial neural networks for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters was developed. Using multilayer feed-forward neural networks with back-propagation algorithm, we developed and tested our program on the basis of 915 measured samples of water-in-glass evacuated tube solar water heaters. This artificial neural networks-based software program automatically obtained accurate heat collection rate and heat loss coefficient using simply "portable test instruments" acquired parameters, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, angle between tubes and ground and final temperature. Our results show that this software (on both personal computer and Android platforms) is efficient and convenient to predict the heat collection rate and heat loss coefficient due to it slow root mean square errors in prediction. The software now can be downloaded from http://t.cn/RLPKF08.

  12. DIAGNOSING THE TIME DEPENDENCE OF ACTIVE REGION CORE HEATING FROM THE EMISSION MEASURE. II. NANOFLARE TRAINS

    SciTech Connect

    Reep, J. W.; Bradshaw, S. J.; Klimchuk, J. A. E-mail: stephen.bradshaw@rice.edu

    2013-02-20

    The time dependence of heating in solar active regions can be studied by analyzing the slope of the emission measure distribution coolward of the peak. In a previous study we showed that low-frequency heating can account for 0% to 77% of active region core emission measures. We now turn our attention to heating by a finite succession of impulsive events for which the timescale between events on a single magnetic strand is shorter than the cooling timescale. We refer to this scenario as a 'nanoflare train' and explore a parameter space of heating and coronal loop properties with a hydrodynamic model. Our conclusions are (1) nanoflare trains are consistent with 86% to 100% of observed active region cores when uncertainties in the atomic data are properly accounted for; (2) steeper slopes are found for larger values of the ratio of the train duration {Delta} {sub H} to the post-train cooling and draining timescale {Delta} {sub C}, where {Delta} {sub H} depends on the number of heating events, the event duration and the time interval between successive events ({tau} {sub C}); (3) {tau} {sub C} may be diagnosed from the width of the hot component of the emission measure provided that the temperature bins are much smaller than 0.1 dex; (4) the slope of the emission measure alone is not sufficient to provide information about any timescale associated with heating-the length and density of the heated structure must be measured for {Delta} {sub H} to be uniquely extracted from the ratio {Delta} {sub H}/{Delta} {sub C}.

  13. Combining Natural Attenuation Capacity and use of Targeted Technological Mitigation Measures for Reducing Diffuse Nutrient Emissions to Surface Waters: The Danish Way

    NASA Astrophysics Data System (ADS)

    Kronvang, B.; Højberg, A. L.; Hoffmann, C. C.; Windolf, J.; Blicher-Mathiesen, G.

    2015-12-01

    Excess nitrogen (N) and phosphorus (P) emissions to surface waters are a high priority environmental problem worldwide for protection of water resources in times of population growth and climate change. As clean water is a scarce resource the struggle for reducing nutrient emissions are an ongoing issue for many countries and regions. Since the mid1980s a wide range of national regulatory general measures have been implemented to reduce land based nitrogen (N) and phosphorus (P) loadings of the Danish aquatic environment. These measures have addressed both point source emissions and emissions from diffuse sources especially from agricultural production. Following nearly 4 decades of combating nutrient pollution our surface waters such as lakes and estuaries are only slowly responding on the 50% reduction in N and 56% reduction in P. Therefore, the implementation of the EU Water Framework Directive in Danish surface waters still call for further reductions of N and P loadings. Therefore, a new era of targeted implemented measures was the outcome of a Commission on Nature and Agriculture established by the Danish Government in 2013. Their White Book points to the need of increased growth and better environment through more targeted and efficient regulation using advanced technological mitigation methods that are implemented intelligently according to the local natural attenuation capacity for nutrients in the landscape. As a follow up a national consensus model for N was established chaining existing leaching, 3D groundwater and surface water models that enable a calculation of the N dynamics and attenuation capacity within a scale of 15 km2. Moreover, several research projects have been conducted to investigate the effect of a suite of targeted mitigation measures such as restored natural wetlands, constructed wetlands, controlled drainage, buffer strips and constructed buffer strips. The results of these studies will be shared in this presentation.

  14. Calorimetry Minisensor for the Localised Measurement of Surface Heat Dissipated from the Human Body

    PubMed Central

    Socorro, Fabiola; Rodríguez de Rivera, Pedro Jesús; Rodríguez de Rivera, Manuel

    2016-01-01

    We have developed a calorimetry sensor that can perform a local measurement of the surface heat dissipated from the human body. The operating principle is based on the law of conductive heat transfer: heat dissipated by the human body passes across a thermopile located between the individual and a thermostat. Body heat power is calculated from the signals measured by the thermopile and the amount of power dissipated across the thermostat in order to maintain a constant temperature. The first prototype we built had a detection area measuring 6 × 6 cm2, while the second prototype, which is described herein, had a 2 × 2 cm2 detection area. This new design offers three advantages over the initial one: (1) greater resolution and three times greater thermal sensitivity; (2) a twice as fast response; and (3) it can take measurements from smaller areas of the body. The sensor has a 5 mW resolution, but the uncertainty is greater, up to 15 mW, due to the measurement and calculation procedure. The order of magnitude of measurements made in healthy subjects ranged from 60 to 300 mW at a thermostat temperature of 28 °C and an ambient room temperature of 21 °C. The values measured by the sensor depend on the ambient temperature and the thermostat’s temperature, while the power dissipated depends on the individual’s metabolism and any physical and/or emotional activity. PMID:27827977

  15. Measurement of frost characteristics on heat exchanger fins. Part 1: Test facility and instrumentation

    SciTech Connect

    Thomas, L.; Chen, H.; Besant, R.W.

    1999-07-01

    A special test facility was developed to characterize frost growing on heat exchanger fins where the cold surfaces and the air supply conditions were similar to those experienced in freezers, i.e., cold surface temperatures ranging from {minus}35 C to {minus}40 C, air supply temperatures from {minus}10 C to {minus}20 C, and 80% to 100% relative humidity (RH). This test facility included a test section with removable fins to measure the frost height and mass concentration. Frost height on heat exchanger fins was measured using a new automated laser scanning system to measure the height of frost and its distribution on selected fins. The increase in air pressure loss resulting from frost growth on the fins was measured directly in the test loop. The frost mass accumulation distribution was measured for each test using special pre-etched fins that could be easily subdivided and weighed. The total heat rate was measured using a heat flux meter. These frost-measuring instruments were calibrated and the uncertainty of each is stated.

  16. Calorimetry Minisensor for the Localised Measurement of Surface Heat Dissipated from the Human Body.

    PubMed

    Socorro, Fabiola; Rodríguez de Rivera, Pedro Jesús; Rodríguez de Rivera, Manuel

    2016-11-06

    We have developed a calorimetry sensor that can perform a local measurement of the surface heat dissipated from the human body. The operating principle is based on the law of conductive heat transfer: heat dissipated by the human body passes across a thermopile located between the individual and a thermostat. Body heat power is calculated from the signals measured by the thermopile and the amount of power dissipated across the thermostat in order to maintain a constant temperature. The first prototype we built had a detection area measuring 6 × 6 cm², while the second prototype, which is described herein, had a 2 × 2 cm² detection area. This new design offers three advantages over the initial one: (1) greater resolution and three times greater thermal sensitivity; (2) a twice as fast response; and (3) it can take measurements from smaller areas of the body. The sensor has a 5 mW resolution, but the uncertainty is greater, up to 15 mW, due to the measurement and calculation procedure. The order of magnitude of measurements made in healthy subjects ranged from 60 to 300 mW at a thermostat temperature of 28 °C and an ambient room temperature of 21 °C. The values measured by the sensor depend on the ambient temperature and the thermostat's temperature, while the power dissipated depends on the individual's metabolism and any physical and/or emotional activity.

  17. Measurements of the Influence of Integral Length Scale on Stagnation Region Heat Transfer

    NASA Technical Reports Server (NTRS)

    Vanfossen, G. James; Ching, Chang Y.

    1994-01-01

    The purpose was twofold: first, to determine if a length scale existed that would cause the greatest augmentation in stagnation region heat transfer for a given turbulence intensity and second, to develop a prediction tool for stagnation heat transfer in the presence of free stream turbulence. Toward this end, a model with a circular leading edge was fabricated with heat transfer gages in the stagnation region. The model was qualified in a low turbulence wind tunnel by comparing measurements with Frossling's solution for stagnation region heat transfer in a laminar free stream. Five turbulence generating grids were fabricated; four were square mesh, biplane grids made from square bars. Each had identical mesh to bar width ratio but different bar widths. The fifth grid was an array of fine parallel wires that were perpendicular to the axis of the cylindrical leading edge. Turbulence intensity and integral length scale were measured as a function of distance from the grids. Stagnation region heat transfer was measured at various distances downstream of each grid. Data were taken at cylinder Reynolds numbers ranging from 42,000 to 193,000. Turbulence intensities were in the range 1.1 to 15.9 percent while the ratio of integral length scale to cylinder diameter ranged from 0.05 to 0.30. Stagnation region heat transfer augmentation increased with decreasing length scale. An optimum scale was not found. A correlation was developed that fit heat transfer data for the square bar grids to within +4 percent. The data from the array of wires were not predicted by the correlation; augmentation was higher for this case indicating that the degree of isotropy in the turbulent flow field has a large effect on stagnation heat transfer. The data of other researchers are also compared with the correlation.

  18. Application of Thin-Film Thermocouples to Localized Heat Transfer Measurements

    NASA Technical Reports Server (NTRS)

    Lepicovsky, J.; Bruckner, R. J.; Smith, F. A.

    1995-01-01

    The paper describes a proof-of-concept experiment on thin-film thermocouples used for localized heat transfer measurements applicable to experiments on hot parts of turbine engines. The paper has three main parts. The first part describes the thin-film sensors and manufacturing procedures. Attention is paid to connections between thin-film thermocouples and lead wires, which has been a source of problems in the past. The second part addresses the test arrangement and facility used for the heat transfer measurements modeling the conditions for upcoming warm turbine tests at NASA LeRC. The paper stresses the advantages of a modular approach to the test rig design. Finally, we present the results of bulk and local heat flow rate measurements, as well as overall heat transfer coefficients obtained from measurements in a narrow passage with an aspect ratio of 11.8. The comparison of bulk and local heat flow rates confirms applicability of thin-film thermocouples to upcoming warm turbine tests.

  19. Heat transfer coefficient measurements on the pressure surface of a transonic airfoil

    NASA Astrophysics Data System (ADS)

    Kodzwa, Paul M.; Eaton, John K.

    2010-02-01

    This paper presents steady-state recovery temperature and heat transfer coefficient measurements on the pressure surface of a modern, highly cambered transonic airfoil. These measurements were collected with a peak Mach number of 1.5 and a maximum turbulence intensity of 30%. We used a single passage model to simulate the idealized two-dimensional flow path between rotor blades in a modern transonic turbine. This set up offered a simpler construction than a linear cascade, yet produced an equivalent flow condition. We performed validated high accuracy (±0.2°C) surface temperature measurements using wide-band thermochromic liquid crystals allowing separate measurements of the previously listed parameters with the same heat transfer surface. We achieved maximum heat transfer coefficient uncertainties that were equivalent to similar investigations (±10%). Two key observations are the heat transfer coefficient along the aft portion of the airfoil is sensitive to the surface heat flux and is highly insensitive to the level of freestream turbulence. Possible explanations for these observations are discussed.

  20. Residual Stress Measurements with Laser Speckle Correlation Interferometry and Local Heat Treating

    SciTech Connect

    Pechersky, M.J.; Miller, R.F.; Vikram, C.S.

    1994-01-06

    A new experimental technique has been devised to measure residual stresses in ductile materials with a combination of laser speckle pattern interferometry and spot heating. The speckle pattern interferometer measures in-plane deformations while the heating provides for very localized stress relief. The residual stresses are determined by the amount of strain that is measured subsequent to the heating and cool-down of the region being interrogated. A simple lumped parameter model is presented to provide a description of the method. This description is followed by presentations of the results of finite element analyses and experimental results with uniaxial test specimens. Excellent agreement between the experiments and the computer analyses were obtained.

  1. Development of a thermal test object for the measurement of ultrasound intracavity transducer self-heating.

    PubMed

    Killingback, Alban L T; Newey, Valentine R; El-Brawany, Mohamed A; Nassiri, Dariush K

    2008-12-01

    The elevated surface temperature of diagnostic ultrasound transducers imposes an important limitation to their safe use in clinical situations. Moreover, particular care should be taken if transvaginal transducers are to be used during routine scans in the first few weeks of pregnancy as the transducer surface can be very close to embryonic/fetal tissues. Published results have shown that the heating of tissue due to transducer self-heating can equal and often exceed the acoustic heating contribution. In this article, we report the development of a portable self contained thermal test object (TTO) capable of assessing the self-heating of intracavity diagnostic ultrasound transducers. The thermal conductivity and volumetric heat capacity of the tissue mimicking material (TMM) used in the TTO were measured, yielding values of (0.56 +/- 0.01) W m(-1) K(-1) and (3.5 +/- 0.8) MJ m(-3) K(-1). The speed of sound of the TMM was measured as 1540 m s(-1) and the attenuation over a frequency range of 2 to 10 MHz was found to be (0.50 +/- 0.01) dB cm(-1) MHz(-1). These results are in excellent agreement with the International Electrotechnical Commission (IEC 60601-2-37) requirements and the previously published properties of biological soft tissue. The temperature stability and uniformity, and suitability of the TTO for the measurement of transducer self-heating were tested and found to be satisfactory. The TTO reached a stable temperature of 37 degrees C in 3 h and the spatial variation in temperature was less than +/- 0.2 degrees C. Lastly, transducer self-heating measurements from a transvaginal transducer exceeded the IEC temperature limit of 43 degrees C in less than 5 min and the temperature reached after 30 min was 47.3 degrees C.

  2. Artificial Neural Networks-Based Software for Measuring Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters

    PubMed Central

    Liu, Zhijian; Liu, Kejun; Li, Hao; Zhang, Xinyu; Jin, Guangya; Cheng, Kewei

    2015-01-01

    Measurements of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, conventional measurement requires expensive detection devices and undergoes a series of complicated procedures. To simplify the measurement and reduce the cost, software based on artificial neural networks for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters was developed. Using multilayer feed-forward neural networks with back-propagation algorithm, we developed and tested our program on the basis of 915measuredsamples of water-in-glass evacuated tube solar water heaters. This artificial neural networks-based software program automatically obtained accurate heat collection rateand heat loss coefficient using simply "portable test instruments" acquired parameters, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, angle between tubes and ground and final temperature. Our results show that this software (on both personal computer and Android platforms) is efficient and convenient to predict the heat collection rate and heat loss coefficient due to it slow root mean square errors in prediction. The software now can be downloaded from http://t.cn/RLPKF08. PMID:26624613

  3. Field Measurement of Fracture/Matrix Heat Exchange using Fiber Optic Distributed Temperature Sensing

    NASA Astrophysics Data System (ADS)

    Hawkins, A.; Becker, M. W.; Tsoflias, G. P.

    2012-12-01

    Highly channelized flow in fractured geologic systems has been blamed for early thermal breakthrough and poor performance of geothermal circulation systems. An experiment is presented in which the effect of channelized flow on fluid/rock heat transfer is measured. Hot water was circulated between two wells (7-14 m separation) completed in a single bedding plane fracture. The elevation of rock matrix temperature was measured using Fiber Optic Distributed Temperature Sensing (DTS). Between wells with good hydraulic connection, heat transfer followed a classic dipole sweep pattern. Between wells with poor hydraulic connection, heat transfer was skewed toward apparent regions of higher transmissivity (or larger aperture). Heat transfer between fracture and matrix was compared with saline tracer circulated between the same wells. Saline distribution was imaged using surface Ground Penetrating Radar. The results suggest that flow channeling can have a significant impact on heat transfer efficiency even in single bedding plane fractures. Temperature rise in the rock matrix above a fracture as a function of time Map view comparison of heat exchange to ground penetrating radar reflection amplitude (a function of fracture aperture). Red is warmer rock, yellow is cooler.

  4. Calorimetric measurement of heat load in full non-inductive LHCD plasmas on TRIAM-1M

    NASA Astrophysics Data System (ADS)

    Hanada, K.; Shinoda, N.; Sugata, T.; Sasaki, K.; Zushi, H.; Nakamura, K.; Sato, K. N.; Sakamoto, M.; Idei, H.; Hasegawa, M.; Kawasaki, S.; Nakashima, H.; Higashijima, A.; Triam Group

    2007-06-01

    Calorimetric measurements using the temperature increment of cooling-water were carried out to estimate the heat load distribution on the plasma facing components (PFCs) in the limiter discharges on TRIAM-1M. Line averaged electron density, ne, and LH power, PLH, dependences of the heat load on PFCs were measured. The heat load on the limiters was proportional to ne1.5 in the range of ne = 0.2-1.0 × 1019 m-3 and PLH1 in the range of PLH = 0.005-0.09 MW. For PLH > 0.1 MW, the plasma transition to an enhanced current drive (ECD) mode appeared and the ne dependences on the heat load on the limiter moderated. This indicates that the heat flux to scrape-off layer (SOL) region was reduced due to the improvement of the plasma confinement. The up-down asymmetry of the heat load on the vacuum vessel was enhanced in the ECD mode, which may be caused by the increasing of the direct loss of energetic electrons.

  5. Time-Resolved Single-State Measurements of the Electronic Structure of Isochoric Heated Copper

    SciTech Connect

    Nelson, A J; Dunn, J; Widmann, K; Ao, T; Ping, Y; Hunter, J; Ng, A

    2004-10-22

    Time-resolved x-ray photoelectron spectroscopy is used to probe the non-steady-state evolution of the valence band electronic structure of laser heated ultra-thin (50 nm) Cu. Single-shot x-ray laser induced time-of-flight photoelectron spectroscopy with picosecond time resolution is used in conjunction with optical measurements of the disassembly dynamics that have shown the existence of a metastable liquid phase in fs-laser heated Cu foils persisting 4-5 ps. This metastable phase is studied using a 527 nm wavelength 400 fs laser pulse containing 0.1-2.5 mJ laser energy focused in a large 500 x 700 {micro}m{sup 2} spot to create heated conditions of 0.07-1.8 x 10{sup 12} W cm{sup -2} intensity. Valence band photoemission spectra showing the changing occupancy of the Cu 3d level with heating are presented. These are the first picosecond x-ray laser time-resolved photoemission spectra of laser-heated ultra-thin Cu foil showing changes in electronic structure. The ultrafast nature of this technique lends itself to true single-state measurements of shocked and heated materials.

  6. Thermal substitution and aerobic efficiency: measuring and predicting effects of heat balance on endotherm diving energetics.

    PubMed

    Lovvorn, J R

    2007-11-29

    For diving endotherms, modelling costs of locomotion as a function of prey dispersion requires estimates of the costs of diving to different depths. One approach is to estimate the physical costs of locomotion (Pmech) with biomechanical models and to convert those estimates to chemical energy needs by an aerobic efficiency (eta=Pmech/Vo2) based on oxygen consumption (Vo2) in captive animals. Variations in eta with temperature depend partly on thermal substitution, whereby heat from the inefficiency of exercising muscles or the heat increment of feeding (HIF) can substitute for thermogenesis. However, measurements of substitution have ranged from lack of detection to nearly complete use of exercise heat or HIF. This inconsistency may reflect (i) problems in methods of calculating substitution, (ii) confounding mechanisms of thermoregulatory control, or (iii) varying conditions that affect heat balance and allow substitution to be expressed. At present, understanding of how heat generation is regulated, and how heat is transported among tissues during exercise, digestion, thermal challenge and breath holding, is inadequate for predicting substitution and aerobic efficiencies without direct measurements for conditions of interest. Confirming that work rates during exercise are generally conserved, and identifying temperatures at those work rates below which shivering begins, may allow better prediction of aerobic efficiencies for ecological models.

  7. When evidence of heat-related vulnerability depends on the contrast measure

    NASA Astrophysics Data System (ADS)

    Benmarhnia, Tarik; Kaufman, Jay S.

    2017-02-01

    Many studies assessing which population subgroups are more vulnerable to heat-related mortality and morbidity have been conducted in recent years. However, given the non-linear (U or J shaped) relationship of temperature with mortality and morbidity, they generally consider only a single contrast measure to report evidence of heat-related vulnerability, despite the possibility that vulnerability depends on the selected contrast measure. In this manuscript, we highlight the importance of considering such issue in further studies by providing evidence for and against heat-related vulnerability using two different temperature contrast measures. We conducted time series analyses to characterize the association between mortality and mean daily temperature in Montreal, Canada (1990-2010). We used age (≥65 vs. 0-64 years) as the effect modifier in stratified analyses. We assessed the presence of effect modification using Cochran Q tests. As contrast measures, we used (1) the percentage change in the outcome above 25 °C, obtained through spline functions showing a linear relationship after this threshold and (2) a comparison of two percentiles (26 vs. 20 °C) of the temperature. We found that evidence of effect modification depended on the contrast measure used. We encourage researchers aiming to identify populations more vulnerable to heat to perform sensitivity analyses using different contrast measures.

  8. Design of a dual chamber heat conduction calorimeter for ultrasonic beam measurement

    NASA Astrophysics Data System (ADS)

    Ong, Hang See

    1997-12-01

    The recent emergence of medical ultrasound dosimetry in terms of Thermal and Mechanical Indices gives rise to the need for a device that is capable of measuring ultrasonic output power quickly and accurately. In the research project described in this dissertation, a dual chamber heat conduction calorimeter (HCC) is designed, built, and tested for the purpose of measuring ultrasonic output power of clinical diagnostic ultrasound devices. The HCC is composed of two identical water filled Aluminum wells housed in two separated compartments of an insulated box. The two compartments form the measuring and reference chambers of the calorimeter. The wells are sealed with plastic membranes that constitute the entrance window for the ultrasound. The bottom of each well is stuffed with a 4cm layer of 0.5cm thick rubber pads. These pads serve as a sonic-to-heat energy exchanger. A small resistive heater is embedded in both rubber pads for calibration purposes. Heat is measured with a series of Seebeck effect thermoelectric devices (thermopiles) sandwiched between the well and the heat sink surrounding the wells. The output voltage signal from the thermopiles is amplified, digitized, then analyzed and displayed in term of Thermal Index with a PC-based system. An optimum measurement technique is derived from an electric circuit model that is representative of the HCC. The performance and sensitivity of the HCC is tested and measured, initially with the embedded resistive heaters, then with an experimental transducer, and lastly with transducers from clinical ultrasound scanners.

  9. Extreme Drought, Fire and Harvest Impacts on Pacific Northwest Forests, and the Effects of Future Climate and Mitigation Measures on the Carbon Balance

    NASA Astrophysics Data System (ADS)

    Law, B. E.; Hudiburg, T. W.; Luyssaert, S.; Coops, N.

    2012-12-01

    Climate change is affecting the odds of extreme weather events, including increased frequency of drought events. Under past and current climate and land management conditions in the Pacific Northwest, natural (drought, fire) and anthropogenic (harvest) disturbances interact across landscapes to affect the carbon balance of forests. Biomass and productivity are high (Hudiburg et al. 2009, 2011), harvest and wildfire are the major disturbances, and harvest removals dominate the net ecosystem carbon balance. We used AmeriFlux observations, inventories, remote sensing data, and models to understand current and future effects on forest distributions and the carbon balance, and the effects of mitigation measures. The region is divided into the mild coastal climate and inland continental conditions with colder winters and drier forests in the rain shadow of the Cascade Mountains. In semi-arid ponderosa pine forests of the East Cascades ecoregion, NEP was reduced by ~44% during a series of extreme drought years compared with a seven year average, consistent with western region average impacts, and there were carry-over effects the following year. Reduction in GPP was proportionately larger than reduction in ecosystem respiration during drought. In the mild climate of the Coast Range, Douglas-fir NEP was reduced ~40% in a single drought year, but recovered quickly in subsequent 'normal' years. Douglas-fir tends to be very plastic and can take up carbon during the winter months when temperature is above freezing, but this isn't seen in ponderosa pine due to colder winter temperatures. Model projections of impacts of future climate on PNW forests suggest larger changes in the eastern dry part of the region, while predicted impacts on Coast Range forests are more variable. Modeling and observations suggest the Pacific Ocean may moderate climate and buffer the coastal forests. With projected increases in extreme drought events, particularly where dry systems are expected to

  10. Comparison of heat transfer measurements with computations for turbulent flow around a 180 deg bend

    NASA Astrophysics Data System (ADS)

    Besserman, D. L.; Tanrikut, S.

    1992-10-01

    Detailed heat transfer measurements for all four walls of a 180-deg 1:1 aspect ratio duct are reported. Experiments using a transient heat transfer technique with liquid crystal thermography were conducted for turbulent flow over a Reynolds number range of 12,500-50,000. Computational results using a Navier-Stokes code are also presented to complement the experiments. Two near-wall shear-stress treatments are evaluated in conjunction with k-epsilon formulation of turbulence to assess their ability to predict high local gradients in heat transfer. Results show that heat transfer on the convex and concave walls is a manifestation of the complex flow field created by the 180-deg bend. For the flat walls, the streamwise average Nusselt number increases approximately two times the fully developed turbulent flow value. The numerical predictions with the two-layer wall integration k-epsilon turbulence model show very good agreement with the experimental data.

  11. Measured performance results: low-cost solar water heating systems in the San Luis Valley

    SciTech Connect

    Swisher, J.

    1983-01-01

    The measured performance of seven low-cost solar water heating systems in the San Luis Valley of southern Colorado is summarized. During the summer and fall of 1981, SERI monitored a variety of low-cost solar water heating system designs and components. Five systems had site-built collectors, and four included low-cost tank-in-jacket heat exchanger/storage tank components. Two were air-to-water systems. The five liquid-based systems included a drain-down design, a propylene glycol-charged thermosiphon system, and three pumped-glycol systems. The pumped-liquid systems performed the best, with system efficiencies greater than 20% and solar fractions between 40% and 70%. Tjhe air-to-water systems did not perform as well because of leakage in the collectors and heat exchangers. The thermosiphon system performed at lower efficiency because the collector flows were low.

  12. Radiation Heat Measurement on Thermally-Isolated Double-Pipe for DC Superconducting Power Transmission

    NASA Astrophysics Data System (ADS)

    Hamabe, M.; Nasu, Y.; Ninomiya, A.; Ishiguro, Y.; Kusaka, S.; Yamaguchi, S.

    2008-03-01

    Multilayer insulator (MLI) is a strong tool for use as a radiation heat shield, though the use of MLI has disadvantages in construction and evacuation for a long superconducting power cable. We have proposed the "MLI-free" radiation heat shielding for DC superconducting power cable and have measured the radiation heat transfer for thermally-isolated double-pipes with different surfaces. Here, Zn coating, MLI, and Al-foil sheet were tested. Consequently, from the radiation heat of 9.7 W/m for bare stainless-steel pipe, Zn-coated stainless-steel surface reduced to 2.6 W/m, whereas the use of MLI reduced to 0.2 W/m. It is expected that the simultaneous use of Zn coating and MLI can reduce the number of total MLI sheets to reduce the evacuation time.

  13. High accuracy heat capacity measurements through the lambda transition of helium with very high temperature resolution

    NASA Technical Reports Server (NTRS)

    Fairbanks, W. M.; Lipa, J. A.

    1984-01-01

    A measurement of the heat capacity singularity of helium at the lambda transition was performed with the aim of improving tests of the Renormalization Group (RG) predictions for the static thermodynamic behavior near the singularity. The goal was to approach as closely as possible to the lambda-point while making heat capacity measurements of high accuracy. To do this, a new temperature sensor capable of unprecedented resolution near the lambda-point, and two thermal control systems were used. A short description of the theoretical background and motivation is given. The initial apparatus and results are also described.

  14. Equation-of-state measurement of dense plasmas heated with fast protons.

    PubMed

    Dyer, G M; Bernstein, A C; Cho, B I; Osterholz, J; Grigsby, W; Dalton, A; Shepherd, R; Ping, Y; Chen, H; Widmann, K; Ditmire, T

    2008-07-04

    Using an ultrafast pulse of mega-electron-volt energy protons accelerated from a laser-irradiated foil, we have heated solid density aluminum plasmas to temperatures in excess of 15 eV. By measuring the temperature and the expansion rate of the heated Al plasma simultaneously and with picosecond time resolution we have found the predictions of the SESAME Livermore equation-of-state (LEOS) tables to be accurate to within 18%, in this dense plasma regime, where there have been few previous experimental measurements.

  15. Equation-of-State Measurement of Dense Plasmas Heated With Fast Protons

    SciTech Connect

    Dyer, G. M.; Bernstein, A. C.; Cho, B. I.; Osterholz, J.; Grigsby, W.; Dalton, A.; Ditmire, T.; Shepherd, R.; Ping, Y.; Chen, H.; Widmann, K.

    2008-07-04

    Using an ultrafast pulse of mega-electron-volt energy protons accelerated from a laser-irradiated foil, we have heated solid density aluminum plasmas to temperatures in excess of 15 eV. By measuring the temperature and the expansion rate of the heated Al plasma simultaneously and with picosecond time resolution we have found the predictions of the SESAME Livermore equation-of-state (LEOS) tables to be accurate to within 18%, in this dense plasma regime, where there have been few previous experimental measurements.

  16. Equation-of-State Measurement of Dense Plasmas Heated With Fast Protons

    NASA Astrophysics Data System (ADS)

    Dyer, G. M.; Bernstein, A. C.; Cho, B. I.; Osterholz, J.; Grigsby, W.; Dalton, A.; Shepherd, R.; Ping, Y.; Chen, H.; Widmann, K.; Ditmire, T.

    2008-07-01

    Using an ultrafast pulse of mega-electron-volt energy protons accelerated from a laser-irradiated foil, we have heated solid density aluminum plasmas to temperatures in excess of 15 eV. By measuring the temperature and the expansion rate of the heated Al plasma simultaneously and with picosecond time resolution we have found the predictions of the SESAME Livermore equation-of-state (LEOS) tables to be accurate to within 18%, in this dense plasma regime, where there have been few previous experimental measurements.

  17. Performance assessment of thermal sensors during short-duration convective surface heating measurements

    NASA Astrophysics Data System (ADS)

    Sahoo, Niranjan; Kumar, Rakesh

    2016-09-01

    The determination of convective surface heating is a very crucial parameter in high speed flow environment. Most of the ground based facilities in this domain have short duration experimental time scale (~milliseconds) of measurements. In these facilities, the calorimetric heat transfer sensors such as thin film gauges (TFGs) and coaxial surface junction thermocouple (CSJT) are quite effective temperature detectors. They have thickness in the range of few microns and have capability of responding in microsecond time scale. The temperature coefficient of resistance (TCR) and the sensitivity are calibration parameter indicators that show the linear change in the resistance of the gauge as a function of temperature. In the present investigation, three of types of heat transfer gauges are fabricated in the laboratory namely, TFG made out of platinum, TFG made out of platinum mixed with CNT and chromel-alumel surface junction coaxial thermocouple (K-type). The calibration parameters of the gauges are determined though oil-bath experiments. The average value TCR and sensitivity of platinum TFG is found to be 0.0024 K-1 and 465 μV/K, while similar values of CSJT are obtained as, 0.064 K-1 and 40.5 μV/K, respectively. The TFG made out of platinum mixed with CNT (5 % by mass) shows the enhancement of TCR as well as sensitivity and the corresponding values are 0.0034 K-1 and 735 μV/K, respectively. The relative performances of heat transfer gauges are compared in a simple laboratory scale experiment in which the gauges are exposed to a sudden step heat load in convection mode for the time duration of 200 ms. The surface heat fluxes are predicted from the temperature history through one dimensional heat conduction modeling. While comparing the experimental results, it is seen that prediction of surface heat flux from all the heat transfer gauges are within the range of ±4 %.