WorldWideScience

Sample records for temperature range rt-3500c

  1. Asymetric change of daily temperature range: Proceedings

    International Nuclear Information System (INIS)

    Kukla, G.; Riches, M.R.

    1994-04-01

    This report is a compilation of abstracts of papers presented at the MINIMAX workshop. Topics include; temperature fluxes, influence of clouds on temperature, anthropogenic influences on temperature flux, and carbon dioxide and aerosol induced greenhouse effect

  2. Variability of Diurnal Temperature Range During Winter Over Western Himalaya: Range- and Altitude-Wise Study

    Science.gov (United States)

    Shekhar, M. S.; Devi, Usha; Dash, S. K.; Singh, G. P.; Singh, Amreek

    2018-04-01

    The current trends in diurnal temperature range, maximum temperature, minimum temperature, mean temperature, and sun shine hours over different ranges and altitudes of Western Himalaya during winter have been studied. Analysis of 25 years of data shows an increasing trend in diurnal temperature range over all the ranges and altitudes of Western Himalaya during winter, thereby confirming regional warming of the region due to present climate change and global warming. Statistical studies show significant increasing trend in maximum temperature over all the ranges and altitudes of Western Himalaya. Minimum temperature shows significant decreasing trend over Pir Panjal and Shamshawari range and significant increasing trend over higher altitude of Western Himalaya. Similarly, sunshine hours show significant decreasing trend over Karakoram range. There exists strong positive correlation between diurnal temperature range and maximum temperature for all the ranges and altitudes of Western Himalaya. Strong negative correlation exists between diurnal temperature range and minimum temperature over Shamshawari and Great Himalaya range and lower altitude of Western Himalaya. Sunshine hours show strong positive correlation with diurnal temperature range over Pir Panjal and Great Himalaya range and lower and higher altitudes.

  3. 33 CFR 159.119 - Operability test; temperature range.

    Science.gov (United States)

    2010-07-01

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

  4. Passive Wireless Temperature Sensors with Enhanced Sensitivity and Range Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal describes the development of passive surface acoustic wave (SAW) temperature sensors with enhanced sensitivity and detection range for NASA application...

  5. The Complex Kinetics of Protein Folding in Wide Temperature Ranges

    OpenAIRE

    Wang, Jin

    2004-01-01

    The complex protein folding kinetics in wide temperature ranges is studied through diffusive dynamics on the underlying energy landscape. The well-known kinetic chevron rollover behavior is recovered from the mean first passage time, with the U-shape dependence on temperature. The fastest folding temperature T0 is found to be smaller than the folding transition temperature Tf. We found that the fluctuations of the kinetics through the distribution of first passage time show rather universal b...

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

    Science.gov (United States)

    Biswas, Shyamal; Jana, Debnarayan

    2012-01-01

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

  7. Nylon coil actuator operating temperature range and stiffness

    Science.gov (United States)

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

    2015-04-01

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

  8. High-temperature absorbed dose measurements in the megagray range

    International Nuclear Information System (INIS)

    Balian, P.; Ardonceau, J.; Zuppiroli, L.

    1988-01-01

    Organic conductors of the tetraselenotetracene family have been tested as ''high-temperature'' absorbed dose dosimeters. They were heated up to 120 0 C and irradiated at this temperature with 1-MeV electrons in order to simulate, in a short time, a much longer γ-ray irradiation. The electric resistance increase of the crystal can be considered a good measurement of the absorbed dose in the range 10 6 Gy to a few 10 8 Gy and presumably one order of magnitude more. This dosimeter also permits on-line (in-situ) measurements of the absorbed dose without removing the sensor from the irradiation site. The respective advantages of organic and inorganic dosimeters at these temperature and dose ranges are also discussed. In this connection, we outline new, but negative, results concerning the possible use of silica as a high-temperature, high-dose dosimeter. (author)

  9. Wide-range temperature controller for use in criogenics

    International Nuclear Information System (INIS)

    Velichkov, L.; Apostolov, A.

    1989-01-01

    A wide range temperature controller capable of working within the 3-300 K range is described. From 3 K to 100 K the controller offers stability from + - 3 0 m u K .h -1 to + - 1 mK.h -1 , correspondingly. It uses a DC resistance bridge with a carbon resistor as a temperature-sensing element. Proportional and integral (PI) type of control is implemented. Special precautions are taken against the transients inherent to the integral control. The adjustments of the PI-regulator for optimum perfomance are straightfoward and convenient. The electronic circuit is built up from available components. 3 figs., 8 refs

  10. Dielectric relaxation in solid collagen over a wide temperature range

    International Nuclear Information System (INIS)

    Khan, Muhammad Abdullah; Rizvi, Tasneem Zahra; Janjua, Khalid Mehmood; Zaheer, Muhammad Yar

    2001-07-01

    Dielectric constant ε' and loss factor ε'' have been measured in bovine tendon collagen in the frequency range 30 Hz - 3 MHz and temperature range 30 deg. C to 200 deg. C. Frequency dependence curve of ε'' shows a low frequency strong α-dispersion attributed to phonon assisted proton hopping between localized sites and a weak high frequency. α 2 - dispersion attributed to reorientation of polar components of collagen molecules. Temperature dependence of the dielectric data show release of bound moisture as a three step process with discrete peaks at 50 deg. C, 90 deg. C and 125 deg. C. These peaks have been attributed to release of adsorbed surface water, water bound to exposed polar sites and strongly bound internal moisture respectively. A peak observed at 160 deg. C has been attributed to thermally induced helix-coil transition of collagen molecules. (author)

  11. Temperature range for critical scaling behavior in YBCO thin films

    Science.gov (United States)

    Deak, J.; Darwin, M. J.; McElfresh, M.

    1993-11-01

    The magnetic and transport properties of thin films and single crystals of YBa 2Cu 3O 7-δ are compared. For measurements on thin films, the apparent critical scaling behavior is observed to exist over a temperature range from 87 K down to the vortex-glass transition Tg = 84.2 K at 2.5 kOE and from 83 K to Tg = 70.4 K at 50 kOe. The inflection point ( Tinf) in temperature dependent resistivity measurements R( T) coincides with the highest temperature at which current-voltage ( I-V) characteristics are found to scale. The region between Tg and Tinf shows a behavior characteristics of thermally activated flux motion, while above TinfI-V curves show ohmic behavior. No similar scaling region is observed in some single crystal results, supporting recent claims that the phase transition in some single crystals may not be critical in nature (of order greater than one).

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

    Science.gov (United States)

    Briga, Michael; Verhulst, Simon

    2015-11-13

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

  13. Changes in diurnal temperature range and national cereal yields

    Energy Technology Data Exchange (ETDEWEB)

    Lobell, D

    2007-04-26

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

  14. MTF measurement of IR optics in different temperature ranges

    Science.gov (United States)

    Bai, Alexander; Duncker, Hannes; Dumitrescu, Eugen

    2017-10-01

    Infrared (IR) optical systems are at the core of many military, civilian and manufacturing applications and perform mission critical functions. To reliably fulfill the demanding requirements imposed on today's high performance IR optics, highly accurate, reproducible and fast lens testing is of crucial importance. Testing the optical performance within different temperature ranges becomes key in many military applications. Due to highly complex IR-Applications in the fields of aerospace, military and automotive industries, MTF Measurement under realistic environmental conditions become more and more relevant. A Modulation Transfer Function (MTF) test bench with an integrated thermal chamber allows measuring several sample sizes in a temperature range from -40 °C to +120°C. To reach reliable measurement results under these difficult conditions, a specially developed temperature stable design including an insulating vacuum are used. The main function of this instrument is the measurement of the MTF both on- and off-axis at up to +/-70° field angle, as well as measurement of effective focal length, flange focal length and distortion. The vertical configuration of the system guarantees a small overall footprint. By integrating a high-resolution IR camera with focal plane array (FPA) in the detection unit, time consuming measurement procedures such as scanning slit with liquid nitrogen cooled detectors can be avoided. The specified absolute accuracy of +/- 3% MTF is validated using internationally traceable reference optics. Together with a complete and intuitive software solution, this makes the instrument a turn-key device for today's state-of- the-art optical testing.

  15. Combining 2-m temperature nowcasting and short range ensemble forecasting

    Directory of Open Access Journals (Sweden)

    A. Kann

    2011-12-01

    Full Text Available During recent years, numerical ensemble prediction systems have become an important tool for estimating the uncertainties of dynamical and physical processes as represented in numerical weather models. The latest generation of limited area ensemble prediction systems (LAM-EPSs allows for probabilistic forecasts at high resolution in both space and time. However, these systems still suffer from systematic deficiencies. Especially for nowcasting (0–6 h applications the ensemble spread is smaller than the actual forecast error. This paper tries to generate probabilistic short range 2-m temperature forecasts by combining a state-of-the-art nowcasting method and a limited area ensemble system, and compares the results with statistical methods. The Integrated Nowcasting Through Comprehensive Analysis (INCA system, which has been in operation at the Central Institute for Meteorology and Geodynamics (ZAMG since 2006 (Haiden et al., 2011, provides short range deterministic forecasts at high temporal (15 min–60 min and spatial (1 km resolution. An INCA Ensemble (INCA-EPS of 2-m temperature forecasts is constructed by applying a dynamical approach, a statistical approach, and a combined dynamic-statistical method. The dynamical method takes uncertainty information (i.e. ensemble variance from the operational limited area ensemble system ALADIN-LAEF (Aire Limitée Adaptation Dynamique Développement InterNational Limited Area Ensemble Forecasting which is running operationally at ZAMG (Wang et al., 2011. The purely statistical method assumes a well-calibrated spread-skill relation and applies ensemble spread according to the skill of the INCA forecast of the most recent past. The combined dynamic-statistical approach adapts the ensemble variance gained from ALADIN-LAEF with non-homogeneous Gaussian regression (NGR which yields a statistical mbox{correction} of the first and second moment (mean bias and dispersion for Gaussian distributed continuous

  16. A combined stochastic analysis of mean daily temperature and diurnal temperature range

    Science.gov (United States)

    Sirangelo, B.; Caloiero, T.; Coscarelli, R.; Ferrari, E.

    2018-03-01

    In this paper, a stochastic model, previously proposed for the maximum daily temperature, has been improved for the combined analysis of mean daily temperature and diurnal temperature range. In particular, the procedure applied to each variable sequentially performs the deseasonalization, by means of truncated Fourier series expansions, and the normalization of the temperature data, with the use of proper transformation functions. Then, a joint stochastic analysis of both the climatic variables has been performed by means of a FARIMA model, taking into account the stochastic dependency between the variables, namely introducing a cross-correlation between the standardized noises. The model has been applied to five daily temperature series of southern Italy. After the application of a Monte Carlo simulation procedure, the return periods of the joint behavior of the mean daily temperature and the diurnal temperature range have been evaluated. Moreover, the annual maxima of the temperature excursions in consecutive days have been analyzed for the synthetic series. The results obtained showed different behaviors probably linked to the distance from the sea and to the latitude of the station.

  17. Diurnal temperature range over Europe between 1950 and 2005

    Directory of Open Access Journals (Sweden)

    K. Makowski

    2008-11-01

    Full Text Available It has been widely accepted that diurnal temperature range (DTR decreased on a global scale during the second half of the twentieth century. Here we show however, that the long-term trend of annual DTR has reversed from a decrease to an increase during the 1970s in Western Europe and during the 1980s in Eastern Europe. The analysis is based on the high-quality dataset of the European Climate Assessment and Dataset Project, from which we selected approximately 200 stations covering the area bordered by Iceland, Algeria, Turkey and Russia for the period 1950 to 2005. We investigate national and regional annual means as well as the pan-European mean with respect to trends and reversal periods. 17 of the 24 investigated regions including the pan-European mean show a statistical significant increase of DTR since 1990 at the latest. Of the remaining 7 regions, two show a non-significant increase, three a significant decrease and two no significant trend. Changes in DTR are affected by both surface shortwave and longwave radiation, the former of which has undergone a change from dimming to brightening in the period considered. Consequently, we discuss the connections between DTR, shortwave radiation and sulfur emissions which are thought to be amongst the most important factors influencing the incoming solar radiation through the primary and secondary aerosol effect. We find reasonable agreement between trends in SO2 emissions, radiation and DTR in areas affected by high pollution. Consequently, we conclude that the trends in DTR could be mostly determined by changes in emissions and the associated changes in incoming solar radiation.

  18. Temperature dependence of thermal expansion of cadmium sulfide in the temperature range 20 - 820 K

    International Nuclear Information System (INIS)

    Oskotskij, V.S.; Kobyakov, I.B.; Solodukhin, A.V.

    1980-01-01

    The linear thermal expansion of cadmium sulfide is measured perpendicularly (α 1 ) and parallelly (α 2 ) to the hexagonal axis in the temperature range from 20 to 820 K. Anisotropy is low at up to 80 K; rises at higher temperatures; at 3OO K α 1 /α 3 ratio is 1.8; at 820 K, 2.4. Heat expansion is negative at temperatures lower than 104.5 K(α 1 ) and 126.0 K(α 2 ). It achieves the minimum at 43.6 K (α 1 ) and 52.5K (α 3 ). The theory of heat expansion is plotted in the Debue, approximation and cadmium sulfide is considered as an isotope crystal with average elastic constants. Two parameters of the theory are determined by the position and value of the minimum of volumetric thermal expansion of the model isotope crystal. The theoretic curve agrees well with the experimental one at temperatures up to 160 K, i.e in the range of applicability of the Debue approximation and the isotropic model

  19. High temperature creep behavior in the (α + β) phase temperature range of M5 alloy

    International Nuclear Information System (INIS)

    Trego, G.

    2011-01-01

    The isothermal steady-state creep behavior of a M5 thin sheet alloy in a vacuum environment was investigated in the (α + β) temperature, low-stress (1-10 MPa) range. To this aim, the simplest approach consists in identifying α and β creep flow rules in their respective single-phase temperature ranges and extrapolating them in the two-phase domain. However, the (α + β) experimental behavior may fall outside any bounds calculated using such creep flow data. Here, the model was improved for each phase by considering two microstructural effects: (i) Grain size: Thermo-mechanical treatments applied on the material yielded various controlled grain size distributions. Creep tests in near-α and near-β ranges evidenced a strong grain-size effect, especially in the diffusional creep regime. (ii) Chemical contrast between the two phases in the (α + β) range: From thermodynamic calculations and microstructural investigations, the β phase is enriched in Nb and depleted in O (the reverse being true for the α phase). Thus, creep tests were performed on model Zr-Nb-O thin sheets with Nb and O concentrations representative of each phase in the considered temperature range. New α and β creep flow equations were developed from this extended experimental database and used to compute, via a finite element model, the creep rates of the two-phase material. The 3D morphology of phases (β grains nucleated at α grain boundaries) was explicitly introduced in the computations. The effect of phase morphology on the macroscopic creep flow was shown using this specific morphology, compared to other typical morphologies and to experimental data. (author) [fr

  20. On the diurnal ranges of Sea Surface Temperature (SST)

    Indian Academy of Sciences (India)

    This paper describes the variability in the diurnal range of SST in the north Indian Ocean using in situ measurements and tests the suitability of simple regression models in estimating the diurnal range.SST measurements obtained from 1556 drifting and 25 moored buoys were used to determine the diurnal range of SSTs.

  1. Low Friction and Wear Surface for Application over a Wide Range of Temperature

    National Research Council Canada - National Science Library

    Bhattacharya, Rabi

    1997-01-01

    ...) and Transmission electron microscopy (TEM), both before and after exposure to high temperatures (up to 700 deg C) in air. Friction measurements were performed at temperatures in the range of room temperature to 700 deg C in air...

  2. A short-range objective nocturnal temperature forecasting model

    Science.gov (United States)

    Sutherland, R. A.

    1980-01-01

    A relatively simple, objective, nocturnal temperature forecasting model suitable for freezing and near-freezing conditions has been designed so that a user, presumably a weather forecaster, can put in standard meteorological data at a particular location and receive an hour-by-hour prediction of surface and air temperatures for that location for an entire night. The user has the option of putting in his own estimates of wind speeds and background sky radiation which are treated as independent variables. An analysis of 141 test runs show that 57.4% of the time the model predicts to within 1 C for the best cases and to within 3 C for 98.0% of all cases.

  3. Thermotaxis of human sperm cells in extraordinarily shallow temperature gradients over a wide range.

    Directory of Open Access Journals (Sweden)

    Anat Bahat

    Full Text Available On the basis of the finding that capacitated (ready to fertilize rabbit and human spermatozoa swim towards warmer temperatures by directing their movement along a temperature gradient, sperm thermotaxis has been proposed to be one of the processes guiding these spermatozoa to the fertilization site. Although the molecular mechanism underlying sperm thermotaxis is gradually being revealed, basic questions related to this process are still open. Here, employing human spermatozoa, we addressed the questions of how wide the temperature range of thermotaxis is, whether this range includes an optimal temperature or whether spermatozoa generally prefer swimming towards warmer temperatures, whether or not they can sense and respond to descending temperature gradients, and what the minimal temperature gradient is to which they can thermotactically respond. We found that human spermatozoa can respond thermotactically within a wide temperature range (at least 29-41°C, that within this range they preferentially accumulate in warmer temperatures rather than at a single specific, preferred temperature, that they can respond to both ascending and descending temperature gradients, and that they can sense and thermotactically respond to temperature gradients as low as <0.014°C/mm. This temperature gradient is astonishingly low because it means that as a spermatozoon swims through its entire body length (46 µm it can sense and respond to a temperature difference of <0.0006°C. The significance of this surprisingly high temperature sensitivity is discussed.

  4. Passive Wireless Temperature Sensors with Enhanced Sensitivity and Range, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal describes the development of passive surface acoustic wave (SAW) temperature sensors with enhanced sensitivity and detection range for NASA application...

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

    Science.gov (United States)

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

    1980-01-01

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

  6. Wide-range temperature dependences of Brillouin scattering properties in polymer optical fiber

    Science.gov (United States)

    Minakawa, Kazunari; Hayashi, Neisei; Shinohara, Yuri; Tahara, Masaki; Hosoda, Hideki; Mizuno, Yosuke; Nakamura, Kentaro

    2014-04-01

    We investigate the temperature dependences of the Brillouin scattering properties in a perfluorinated graded-index (PFGI-) polymer optical fiber (POF) in a wide temperature range from -160 to 125 °C. The temperature dependences of the Brillouin frequency shift, linewidth, and Stokes power are almost linear at lower temperature down to -160 °C while they show nonlinear dependences at higher temperature. These behaviors appear to originate from the partial glass transition of the polymer material.

  7. Determination of plant growth rate and growth temperature range from measurement of physiological parameters

    Science.gov (United States)

    R. S. Criddle; B. N. Smith; L. D. Hansen; J. N. Church

    2001-01-01

    Many factors influence species range and diversity, but temperature and temperature variability are always major global determinants, irrespective of local constraints. On a global scale, the ranges of many taxa have been observed to increase and their diversity decrease with increasing latitude. On a local scale, gradients in species distribution are observable with...

  8. Methanol adsorption by amorphous silica alumina in the critical temperature range

    NARCIS (Netherlands)

    Kuczynski, M.; van Ooteghem, A.; Westerterp, K.R.

    1986-01-01

    The methanol adsorption capacity of an amorphous silica-alumina was measured using an equilibrium technique. The experimental temperature range was of 140 to 260°C and the pure methanol pressure range was 0.1 to 1.2 MPa. A multilayer adsorption was found, also for temperatures above the critical

  9. Investigations of Temperatures of Phase Transformations of Low-Alloyed Reinforcing Steel within the Heat Treatment Temperature Range

    Directory of Open Access Journals (Sweden)

    Kargul T.

    2017-06-01

    Full Text Available The paper presents the results of DSC analysis of steel B500SP produced in the process of continuous casting, which is intended for the production reinforcement rods with high ductility. Studies were carried out in the temperature range below 1000°C in a protective atmosphere of helium during samples heating program. The main objective of the study was to determine the temperature range of austenite structure formation during heating. As a result of performed experiments: Ac1s, Ac1f – temperatures of the beginning and finish of the eutectoid transformation, Ac2 – Curie temperature of the ferrite magnetic transformation and the temperature Ac3 of transformation of proeutectoid ferrite into austenite were elaborated. Experimental determination of phase transformations temperatures of steel B500SP has great importance for production technology of reinforcement rods, because good mechanical properties of rods are formed by the special thermal treatment in Tempcore process.

  10. Transducer-based fiber Bragg grating high-temperature sensor with enhanced range and stability

    Science.gov (United States)

    Mamidi, Venkata Reddy; Kamineni, Srimannarayana; Ravinuthala, Lakshmi Narayana Sai Prasad; Tumu, Venkatappa Rao

    2017-09-01

    Fiber Bragg grating (FBG)-based high-temperature sensor with enhanced-temperature range and stability has been developed and tested. The sensor consists of an FBG and a mechanical transducer, which furnishes a linear temperature-dependent tensile strain on FBG by means of differential linear thermal expansion of two different ceramic materials. The designed sensor is tested over a range: 20°C to 1160°C and is expected to measure up to 1500°C.

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

    Science.gov (United States)

    Johnson, Kenneth R. (Inventor)

    1995-01-01

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

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

    Science.gov (United States)

    Hammoud, Ahmad; Patterson, Richard L.

    2009-01-01

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

  13. Damage of high-chromium steels under deformation in a wide temperature range

    Science.gov (United States)

    Skripnyak, N. V.; Emelyanova, E. S.; Skripnyak, V. A.; Skripnyak, E. G.

    2017-12-01

    High-chromium steels have high strength properties, corrosion properties and resistance to neutron irradiation, thereby are considered as promising steels for nuclear reactors of generation IV. The deformation and damage of high chromium steels in a wide temperature range was studied by numerical simulation method. A model was proposed to predict the deformation and damage of high chromium steels under quasi-static loading within the temperature range from 295 to 1100 K. It is shown that the ductility of high-chromium steels increases proportionally to temperature in the range from 750 to 1100 K due to the growth of α'-phase precipitates.

  14. A passively aligned VCSEL transmitter operating at fixed current over a wide temperature range.

    Science.gov (United States)

    Park, Jonghyun; Kim, Taeyong; Kim, Sung-Han; Kim, Sang-Bae

    2009-03-30

    We have investigated low-current operation characteristics of a passively aligned VCSEL transmitter driven at fixed "on" and "off" current over a wide temperature range. GaAs/AlGaAs-based 850-nm oxide VCSELs with the minimum threshold current of 0.79 mA at 50 masculineC and small temperature dependence of the threshold current, d(2)I(th)/dT(2), as low as 0.114 muA/ masculineC(2) have been fabricated and used for the transmitter module. The superior temperature characteristics enable fixed-current operation of the VCSEL transmitter that complies with Gigabit Ethernet standard over a wide temperature range from -20 to 120 masculineC. This result paves the way to a VCSEL transmitter featured by low-power consumption, low-cost with a simple driving circuit and passive alignment, and a wide operation temperature range.

  15. New England observed and predicted August stream/river temperature daily range points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted August stream/river temperature daily ranges in New England based on a spatial statistical...

  16. New England observed and predicted July stream/river temperature daily range points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted July stream/river temperature daily ranges in New England based on a spatial statistical network...

  17. Wide Temperature Range DC-DC Boost Converters for Command/Control/Drive Electronics, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We shall develop wide temperature range DC-DC boost converters that can be fabricated using commercial CMOS foundries. The boost converters will increase the low...

  18. Reaction rate constants of HO2 + O3 in the temperature range 233-400 K

    Science.gov (United States)

    Wang, Xiuyan; Suto, Masako; Lee, L. C.

    1988-01-01

    The reaction rate constants of HO2 + O3 were measured in the temperature range 233-400 K using a discharge flow system with photofragment emission detection. In the range 233-253 K, the constants are approximately a constant value, and then increase with increasing temperature. This result suggests that the reaction may have two different channels. An expression representing the reaction rate constants is presented.

  19. Short-range order above the Curie temperature in the dynamic spin-fluctuation theory

    International Nuclear Information System (INIS)

    Melnikov, N.B.; Reser, B.I.

    2016-01-01

    Based on the dynamic spin-fluctuation theory, we study the spin-density correlations in the ferromagnetic metals. We obtain computational formulae for the correlation function and correlation radius in different approximations of the theory. Using these formulae, we calculate the magnetic short-range order above the Curie temperature in bcc Fe. Results of the calculation confirm our theoretical prediction that the inverse correlation radius increases linearly with temperature for T sufficiently large. The calculated short-range order is small but sufficient to correctly describe neutron scattering experiments. A considerable amount of the short-range order is shown to persist up to temperatures much higher than the Curie temperature. - Highlights: • We study the spin correlations in ferromagnetic metals above the Curie temperature. • We derive computational formulae for the spin correlator and correlation radius. • The correlation radius decreases inversely with temperature over a wide interval. • The calculated short-range order in Fe is small, in agreement with experiment. • A considerable amount of short-range order in Fe persists up to high temperatures.

  20. The reactions of OH radicals with chloroalkanes in the temperature range 295-360 K

    DEFF Research Database (Denmark)

    Markert, F.; Nielsen, O.J.

    1992-01-01

    The temperature dependency of the rate constants for the gas phase reaction of OH radicals with a series of chloroalkanes was measured in the temperature range from 295 to 360 K at a total pressure of 1 atm. The rate constants were obtained by using the absolute technique of pulse radiolysis comb...

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

    Science.gov (United States)

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

    2002-01-01

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

  2. The variability of atmospheric equivalent temperature for radar altimeter range correction

    Science.gov (United States)

    Liu, W. Timothy; Mock, Donald

    1990-01-01

    Two sets of data were used to test the validity of the presently used approximation for radar altimeter range correction due to atmospheric water vapor. The approximation includes an assumption of constant atmospheric equivalent temperature. The first data set includes monthly, three-dimensional, gridded temperature and humidity fields over global oceans for a 10-year period, and the second is comprised of daily or semidaily rawinsonde data at 17 island stations for a 7-year period. It is found that the standard method underestimates the variability of the equivalent temperature, and the approximation could introduce errors of 2 cm for monthly means. The equivalent temperature is found to have a strong meridional gradient, and the highest temporal variabilities are found over western boundary currents. The study affirms that the atmospheric water vapor is a good predictor for both the equivalent temperature and the range correction. A relation is proposed to reduce the error.

  3. Ultra-sensitive wide dynamic range temperature sensor based on in-fiber Lyot interferometer

    Science.gov (United States)

    Nikbakht, Hamed; Poorghdiri Isfahani, Mohamad Hosein; Latifi, Hamid

    2017-04-01

    An in-fiber Lyot interferometer for temperature measurement is presented. The sensor utilizes high temperature-dependence of the birefringence in Panda polarization maintaining fibers to achieve high resolution in temperature measurements. Temperature variation modulates the phase difference between the polarization modes propagating in different modes of the Panda fiber. The Lyot interferometer produces a spectrum which varies with the phase difference. Therefore, by monitoring this spectrum a high resolution of 0.003°C was achieved. A fiber Bragg grating is added to the setup to expand its dynamic range. This sensor does not need complicated fabrication process and can be implemented in many applications.

  4. Interaction processes between vacancies and dislocations in molybdenum in the temperature range around 0.3 of the melting temperature

    Energy Technology Data Exchange (ETDEWEB)

    Zelada-Lambri, G.I. [Facultad de Ciencias Exactas, Ingenieria y Agrimensura, Universidad Nacional de Rosario, Laboratorio de Materiales, Escuela de Ingenieria Electrica, Avenida Pellegrini 250, 2000 Rosario (Argentina); Lambri, O.A. [Facultad de Ciencias Exactas, Ingenieria y Agrimensura, Universidad Nacional de Rosario, Laboratorio de Materiales, Escuela de Ingenieria Electrica, Avenida Pellegrini 250, 2000 Rosario (Argentina); Instituto de Fisica Rosario, Member of the CONICET' s Research Staff (Argentina)], E-mail: olambri@fceia.unr.edu.ar; Bozzano, P.B. [Laboratorio de Microscopia Electronica, Unidad de Actividad Materiales, Centro Atomico Constituyentes, Comision Nacional de Energia Atomica, Avenida General Paz 1499, 1650 San Martin (Argentina); Garcia, J.A. [Departamento de Fisica Aplicada II, Facultad de Ciencias y Tecnologia, Universidad del Pais Vasco, Apartado 644, 48080 Bilbao, Pais Vasco (Spain); Celauro, C.A. [Reactor Nuclear RA-4, Facultad de Ciencias Exactas, Ingenieria y Agrimensura, Universidad Nacional de Rosario, Riobamba y Berruti, 2000 Rosario (Argentina)

    2008-10-15

    Mechanical spectroscopy, electrical resistivity and transmission electron microscopy studies have been performed on pre-strained neutron irradiated single crystalline molybdenum in order to check the interaction processes between vacancies and dislocations in the temperature range between room temperature and 1273 K. The anelastic relaxation in molybdenum which appears between 800 K and 1273 K has been separated in two different physical mechanisms depending on the temperature of appearance of the relaxation peak. The physical mechanism which controls the damping peak appearing at around 800 K was related with the dragging of jogs by the dislocation under movement assisted by vacancy diffusion. The damping peak which appears at higher temperatures of about 1000 K was more consistent with the formation and diffusion of vacancies assisted by the dislocation movement.

  5. Critical current measurements of high-temperature superconducting short samples at a wide range of temperatures and magnetic fields

    Science.gov (United States)

    Ma, Hongjun; Liu, Huajun; Liu, Fang; Zhang, Huahui; Ci, Lu; Shi, Yi; Lei, Lei

    2018-01-01

    High-Temperature Superconductors (HTS) are potential materials for high-field magnets, low-loss transmission cables, and Superconducting Magnetic Energy Storage (SMES) due to their high upper critical magnetic field (Hc2) and critical temperature (Tc). The critical current (Ic) of HTS, which is one of the most important parameters for superconductor application, depends strongly on the magnetic fields and temperatures. A new Ic measurement system that can carry out accurate Ic measurement for HTS short samples with various temperatures (4.2-80 K), magnetic fields (0-14 T), and angles of the magnetic field (0°-90°) has been developed. The Ic measurement system mainly consists of a measurement holder, temperature-control system, background magnet, test cryostat, data acquisition system, and DC power supply. The accuracy of temperature control is better than ±0.1 K over the 20-80 K range and ±0.05 K when measured below 20 K. The maximum current is over 1000 A with a measurement uncertainty of 1%. The system had been successfully used for YBa2Cu3O7-x(YBCO) tapes Ic determination with different temperatures and magnetic fields.

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

    Science.gov (United States)

    LaQuay, Ryan Matthew

    2011-01-01

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

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

    Science.gov (United States)

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

    2012-01-01

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

  8. The range of medication storage temperatures in aeromedical emergency medical services.

    Science.gov (United States)

    Madden, J F; O'Connor, R E; Evans, J

    1999-01-01

    The United States Pharmacopoeia (USP) recommends that medication storage temperatures should be maintained between 15 degrees C and 30 degrees C (59 degrees F to 86 degrees F). Concerns have been raised that storage temperatures in EMS may deviate from this optimal range, predisposing drugs to degradation. This study was conducted to determine whether temperatures inside the drug box carried by paramedics aboard a helicopter remained within the range. The Aviation Section, with a paramedic on board, utilizes two helicopters and conducts approximately 80 patient care flights per month. A dual-display indoor/outdoor thermometer with memory was used to measure the highest and lowest temperatures during each shift. The thermometer was kept with medications in a nylon drug bag, which remained on the helicopter except when needed for patient care. Ambient temperature measurements at the location of the helicopter base were obtained from the National Climatic Data Center. Temperature ranges were recorded during day shift (8 AM to 4 PM) and night shift (4 PM to 12 AM) during the winter from December 1, 1995, to March 13, 1996, and summer from June 17, 1996, to September 14, 1996. Statistical analysis was performed using chi-square and the Bonferroni-adjusted t-test. Compared with the winter day period, the winter night period had lower minimum (13.2 degrees C vs 14.7 degrees C, p = 0.003) and maximum (20.3 degrees C vs 21.2 degrees C, p = 0.02) temperatures. Both were below the USP minimum. The summer day period had higher maximum temperatures than the summer night period (31.2 degrees C vs 27.6 degrees C, p = 5 x 10(-9)). The mean daytime summer maximum exceeded the USP upper limit. Storage temperatures outside of the USP range were observed during 49% of winter days, 62% of winter nights, 56% of summer days, and 27% of summer nights. There was a significant tendency for summer days (p = 8 x 10(-8)) and winter nights (p = 0.009) to be outside of the acceptable range

  9. Thermal Stability of Austempered Ductile Iron Evaluated in a Temperature Range of 20-300K

    Directory of Open Access Journals (Sweden)

    Dawid MYSZKA

    2016-05-01

    Full Text Available The aim of this article was to determine through changes in magnetic properties the stability of the austempered ductile iron (ADI microstructure during temperature changes in a range of 20 – 300 K. The measurements were taken in a vibrating sample magnetometer (VSM using Fe27Ni2TiMoAlNb austenitic stainless steel and four types of austempered ductile iron obtained under various heat treatment conditions. The plotted curves showing changes in the magnetisation degree as a function of temperature had a number of characteristic points illustrating changes taking place in the microstructure. For each of the materials examined, the martensite start temperature Ms and the temperature range within which the martensitic transformation takes place were identified.

  10. Thermal conductivity and thermal diffusivity of tantalum in the temperature range from 293 to 1800 K

    Science.gov (United States)

    Savchenko, I. V.; Stankus, S. V.

    2008-12-01

    Thermal diffusivity of polycrystalline tantalum at the temperature range from 293 to 1800 K has been measured by the laser flash method with the error of 2-4 %. Thermal conductivity has been calculated with the use of reference data on density and heat capacity. Approximating equations and tables of reference data for the temperature dependence of heat transfer coefficients have been obtained; comparison with the published data has been carried out.

  11. Lattice Parameter of Polycrystalline Diamond in the Low-Temperature Range

    International Nuclear Information System (INIS)

    Paszkowicz, W.; Piszora, P.; Lasocha, W.; Margiolaki, I.; Brunelli, M.; Fitch, A.

    2010-01-01

    The lattice parameter for polycrystalline diamond is determined as a function of temperature in the 4-300 K temperature range. In the range studied, the lattice parameter, expressed in angstrom units, of the studied sample increases according to the equation a = 3.566810(12) + 6.37(41) x 10 -14 T 4 (approximately, from 3.5668 to 3.5673 A). This increase is larger than that earlier reported for pure single crystals. The observed dependence and the resulting thermal expansion coefficient are discussed on the basis of literature data reported for diamond single crystals and polycrystals. (authors)

  12. Temperature Range Shifts for Three European Tree Species over the Last 10,000 Years.

    Science.gov (United States)

    Cheddadi, Rachid; Araújo, Miguel B; Maiorano, Luigi; Edwards, Mary; Guisan, Antoine; Carré, Matthieu; Chevalier, Manuel; Pearman, Peter B

    2016-01-01

    We quantified the degree to which the relationship between the geographic distribution of three major European tree species, Abies alba, Fagus sylvatica and Picea abies and January temperature (Tjan) has remained stable over the past 10,000 years. We used an extended data-set of fossil pollen records over Europe to reconstruct spatial variation in Tjan values for each 1000-year time slice between 10,000 and 3000 years BP (before present). We evaluated the relationships between the occurrences of the three species at each time slice and the spatially interpolated Tjan values, and compared these to their modern temperature ranges. Our results reveal that F. sylvatica and P. abies experienced Tjan ranges during the Holocene that differ from those of the present, while A. alba occurred over a Tjan range that is comparable to its modern one. Our data suggest the need for re-evaluation of the assumption of stable climate tolerances at a scale of several thousand years. The temperature range instability in our observed data independently validates similar results based exclusively on modeled Holocene temperatures. Our study complements previous studies that used modeled data by identifying variation in frequencies of occurrence of populations within the limits of suitable climate. However, substantial changes that were observed in the realized thermal niches over the Holocene tend to suggest that predicting future species distributions should not solely be based on modern realized niches, and needs to account for the past variation in the climate variables that drive species ranges.

  13. An Explosive Range Model Based on the Gas Composition, Temperature, and Pressure during Air Drilling

    Directory of Open Access Journals (Sweden)

    Xiangyu Fan

    2016-01-01

    Full Text Available Air drilling is low cost and effectively improves the penetration rate and causes minimal damage to liquid-sensitive pay zones. However, there is a potential downhole explosion when combustible gas mixed with drilling fluid reaches the combustible condition. In this paper, based on the underground combustion mechanism, an explosive range calculation model is established. This model couples the state equation and the empirical formula method, which considers the inert gas content, pressure, mixed gas component, and temperature. The result shows that increase of the inert gas content narrows the explosive range, while increase of the gas temperature and pressure improves the explosive range. A case in Chongqing, China, is used to validate the explosive range calculation model.

  14. A wide temperature range irradiation cryostat for reasearch on solid state targets

    Energy Technology Data Exchange (ETDEWEB)

    Reeve, Scott; Dutz, Hartmut; Goertz, Stefan; Runkel, Stefan; Voge, Thomas [Physikalisches Institut, Universitaet Bonn (Germany)

    2012-07-01

    To qualitatively improve the data obtained in asymmetry measurements of scattering experiments the figure of merit (FOM) plays a major role and can reduce the data acquisition time when a certain precision in the measurement is needed. One of the defining factors for the improvement of the polarised experiment lies in the target choice and preparation, in particular the method employed to introduce the paramagnetic defects for the use of dynamic nuclear polarisation (DNP). To this end the Polarized Target Group in Bonn has developed a wide range temperature cryostat for the irradiation of potential target materials in which materials can be irradiated to varying doses at specified temperatures. The stable irradiation temperature of the materials can be controlled to within {+-}1 K over a range of 90 K

  15. An alternate method for achieving temperature control in the -130 C to 75 C range

    Science.gov (United States)

    Johnson, Kenneth R.; Anderson, Mark R.; Lane, Robert W.; Cortez, Maximo G.

    1992-01-01

    Thermal vacuum testing often requires temperature control of chamber shrouds and heat exchangers within the -130 C to 75 C range. There are two conventional methods which are normally employed to achieve control through this intermediate temperature range: (1) single-pass flow where control is achieved by alternately pulsing hot gaseous nitrogen (GN2) and cold LN2 into the feed line to yield the setpoint temperature; and (2) closed-loop circulation where control is achieved by either electrically heating or LN2 cooling the circulating GN2 to yield the setpoint temperature. A third method, using a mass flow ratio controller along with modulating control valves on GN2 and LN2 lines, provides excellent control but equipment for this method is expensive and cost-prohibitive for all but long-term continuous processes. The single-pass method provides marginal control and can result in unexpected overcooling of the test article from even a short pulse of LN2. The closed-loop circulation method provides excellent control but requires an expensive blower capable of operating at elevated pressures and cryogenic temperatures. Where precise control is needed (plus or minus 2 C), single-pass flow systems typically have not provided the precision required, primarily because of overcooling temperature excursions. Where several individual circuits are to be controlled at different temperatures, the use of expensive cryogenic blowers for each circuit is also cost-prohibitive, especially for short duration of one-of-a-kind tests. At JPL, a variant of the single-pass method was developed that was shown to provide precise temperature control in the -130 C to 75 C range while exhibiting minimal setpoint overshoot during temperature transitions. This alternate method uses a commercially available temperature controller along with a GN2/LN2 mixer to dampen the amplitude of cold temperature spikes caused by LN2 pulsing. The design of the GN2/LN2 mixer, the overall control system

  16. A luminescent Lanthanide-free MOF nanohybrid for highly sensitive ratiometric temperature sensing in physiological range.

    Science.gov (United States)

    Zhou, You; Zhang, Denan; Zeng, Jin; Gan, Ning; Cuan, Jing

    2018-05-01

    Luminescent MOF materials with tunable emissions and energy/charge transfer processes have been extensively explored as ratiometric temperature sensors. However, most of the ratiometric MOF thermometers reported thus far are based on the MOFs containing photoactive lanthanides, which are potentially facing cost issue and serious supply shortage. Here, we present a ratiometric luminescent thermometer based on a dual-emitting lanthanide-free MOF hybrid, which is developed by encapsulation of a fluorescent dye into a robust nanocrystalline zirconium-based MOF through a one-pot synthesis approach. The structure and morphology of the hybrid product was characterized by Powder X-ray diffraction (PXRD), N 2 adsorption-desorption measurement and Scanning electron microscopy (SEM). The pore confinement effect well isolates the guest dye molecules and therefore suppresses the nonradiative energy transfer process between dye molecules. The incorporated dye emission is mainly sensitized by the organic linkers within MOF through fluorescence resonance energy transfer. The ratiometric luminescence of the MOF hybrid shows a significant response to temperature due to the thermal-related back energy transfer process from dye molecules and organic linkers, thus can be exploited for self-calibrated temperature sensing. The maximum thermometric sensitivity is 1.19% °C -1 in the physiological temperature range, which is among the highest for the ratiomtric MOF thermometers that operating in 25-45°C. The temperature resolution is better than 0.1°C over the entire operative range (20-60°C). By integrating the advantages of excellent stability, nanoscale nature, and high sensitivity and precision in the physiological temperature range, this dye@MOF hybrid might have potential application in biomedical diagnosis. What' more, this work has expanded the possibility of non-lanthanide luminescent MOF materials for the development of ratiometric temperature sensors. Copyright © 2018

  17. Tensile properties and fracture mechanism of IN-100 superalloy in high temperature range

    Directory of Open Access Journals (Sweden)

    Milan T. Jovanović

    2017-06-01

    Full Text Available Tensile properties and fracture mechanism of a polycrystalline IN-100 superalloy have been investigated in the range from room temperature to 900°C. Optical microscopy (OM and transmission electron microscopy (TEM applying replica technique were used for microstructural investigation, whereas scanning electron microscopy (SEM was utilized for fracture study. High temperature tensile tests were carried out in vacuumed chamber. Results show that strength increases up to 700°C, and then sharply decreases with further increase in temperature. Elongation increases very slowly (6-7.5% till 500°C, then decreases to 4.5% at 900°C. Change in elongation may be ascribed to a change of fracture mechanism. Appearance of a great number of microvoids prevails up to 500°C resulting in a slow increase of elongation, whereas above this temperature elongation decrease is correlated with intergranular crystallographic fracture and fracture of carbides.

  18. Long-range correlations in rectal temperature fluctuations of healthy infants during maturation.

    Directory of Open Access Journals (Sweden)

    Georgette Stern

    Full Text Available BACKGROUND: Control of breathing, heart rate, and body temperature are interdependent in infants, where instabilities in thermoregulation can contribute to apneas or even life-threatening events. Identifying abnormalities in thermoregulation is particularly important in the first 6 months of life, where autonomic regulation undergoes critical development. Fluctuations in body temperature have been shown to be sensitive to maturational stage as well as system failure in critically ill patients. We thus aimed to investigate the existence of fractal-like long-range correlations, indicative of temperature control, in night time rectal temperature (T(rec patterns in maturing infants. METHODOLOGY/PRINCIPAL FINDINGS: We measured T(rec fluctuations in infants every 4 weeks from 4 to 20 weeks of age and before and after immunization. Long-range correlations in the temperature series were quantified by the correlation exponent, alpha using detrended fluctuation analysis. The effects of maturation, room temperature, and immunization on the strength of correlation were investigated. We found that T(rec fluctuations exhibit fractal long-range correlations with a mean (SD alpha of 1.51 (0.11, indicating that T(rec is regulated in a highly correlated and hence deterministic manner. A significant increase in alpha with age from 1.42 (0.07 at 4 weeks to 1.58 (0.04 at 20 weeks reflects a change in long-range correlation behavior with maturation towards a smoother and more deterministic temperature regulation, potentially due to the decrease in surface area to body weight ratio in the maturing infant. alpha was not associated with mean room temperature or influenced by immunization CONCLUSIONS: This study shows that the quantification of long-range correlations using alpha derived from detrended fluctuation analysis is an observer-independent tool which can distinguish developmental stages of night time T(rec pattern in young infants, reflective of maturation of

  19. Predicting the thermal conductivity of aluminium alloys in the cryogenic to room temperature range

    Science.gov (United States)

    Woodcraft, Adam L.

    2005-06-01

    Aluminium alloys are being used increasingly in cryogenic systems. However, cryogenic thermal conductivity measurements have been made on only a few of the many types in general use. This paper describes a method of predicting the thermal conductivity of any aluminium alloy between the superconducting transition temperature (approximately 1 K) and room temperature, based on a measurement of the thermal conductivity or electrical resistivity at a single temperature. Where predictions are based on low temperature measurements (approximately 4 K and below), the accuracy is generally better than 10%. Useful predictions can also be made from room temperature measurements for most alloys, but with reduced accuracy. This method permits aluminium alloys to be used in situations where the thermal conductivity is important without having to make (or find) direct measurements over the entire temperature range of interest. There is therefore greater scope to choose alloys based on mechanical properties and availability, rather than on whether cryogenic thermal conductivity measurements have been made. Recommended thermal conductivity values are presented for aluminium 6082 (based on a new measurement), and for 1000 series, and types 2014, 2024, 2219, 3003, 5052, 5083, 5086, 5154, 6061, 6063, 6082, 7039 and 7075 (based on low temperature measurements in the literature).

  20. Effects of regional temperature on electric vehicle efficiency, range, and emissions in the United States.

    Science.gov (United States)

    Yuksel, Tugce; Michalek, Jeremy J

    2015-03-17

    We characterize the effect of regional temperature differences on battery electric vehicle (BEV) efficiency, range, and use-phase power plant CO2 emissions in the U.S. The efficiency of a BEV varies with ambient temperature due to battery efficiency and cabin climate control. We find that annual energy consumption of BEVs can increase by an average of 15% in the Upper Midwest or in the Southwest compared to the Pacific Coast due to temperature differences. Greenhouse gas (GHG) emissions from BEVs vary primarily with marginal regional grid mix, which has three times the GHG intensity in the Upper Midwest as on the Pacific Coast. However, even within a grid region, BEV emissions vary by up to 22% due to spatial and temporal ambient temperature variation and its implications for vehicle efficiency and charging duration and timing. Cold climate regions also encounter days with substantial reduction in EV range: the average range of a Nissan Leaf on the coldest day of the year drops from 70 miles on the Pacific Coast to less than 45 miles in the Upper Midwest. These regional differences are large enough to affect adoption patterns and energy and environmental implications of BEVs relative to alternatives.

  1. Effect of diurnal temperature range on cardiovascular markers in the elderly in Seoul, Korea

    Science.gov (United States)

    Lim, Youn-Hee; Kim, Ho; Kim, Jin Hee; Bae, Sanghyuk; Hong, Yun-Chul

    2013-07-01

    While diurnal temperature range (DTR) has been found to be a risk factor for mortality, evaluation of the underlying mechanisms involved in this association are lacking. To explain the association between DTR and health effects, we investigated how cardiovascular markers responded to DTR. Data was obtained from 560 participants who regularly attended a community elderly welfare center located in Seoul, Korea. Data collection was conducted a total of five times over a 3-year period beginning in August, 2008. We examined systolic and diastolic blood pressure (BP), heart rate (HR), and heart rate variability (HRV). Mixed-effects models and generalized additive mixed models were used to assess the relationship of DTR with BP, HR, and HRV. BP was not associated significantly with rapid temperature changes during the day. While HR was associated linearly with increments of DTR, the relationship between DTR and HRV showed nonlinear associations, or the presence of a cutoff around median DTR. At the cutoff level of DTR determined by an inflection point in the graph, standard deviation of normal-to-normal intervals (SDNN) and root mean square successive difference (RMSSD) were peaked, whereas the low frequency:high frequency (LF:HF) ratio was elevated with decreasing DTR below the cutoff level. The study demonstrated that HR increases with increasing temperature range during the day, and that HRV is reduced at small or large DTR, which suggests minimal cardiovascular stress around the median level of temperature range during the day.

  2. [Study and analysis of light infrared detection system with dual spectrum and wide temperature range].

    Science.gov (United States)

    Shen, Man-De; Jiang, Qing-Xiu; Ren, Huan-Huan; Li, Cheng

    2014-05-01

    Because harmonic diffractive optics elements has special achromatism, athermalization and arbitrary phase modulation characteristics, an infrared detection system method with dual spectrum and wide temperature range was presented based on the most advanced infrared dual color detector which had a format of 320 X 240 and the pixel pitch of 30 microm. A hybrid refractive/ harmonic diffractive infrared detection system with dual spectrum and wide temperature range was designed. The working wavelength range was 3. 8 - 4. 2 and 8. 8 -11. 2 microm. The system was only consisted of three lenses, including one aspheric surfaces and a harmonic diffraction surface, which made the system have compact structure and light weight. In the temperature range -120 -200 degreesC, the RMS radius of spot diagram in 3. 8 approximately 4. 2 and 8. 8-11. 2 pm was 19. 07 and 17. 75 microm respectively, which is less than the pixel size of infrared detector with 30 m, the enclosed energy in 30 microm, the enclosed energy in 3. 8-4. 2 and 8. 8-11. 2 microm is 88. 7% and 82. 4% in two pixel size. The method and structure was convenient and predominant. It was proved that the design was feasible.

  3. Temperature range shifts for three European tree species over the last 10,000 years

    Directory of Open Access Journals (Sweden)

    Rachid Cheddadi

    2016-10-01

    Full Text Available We quantified the degree to which the relationship between the geographic distribution of three major European tree species, Abies alba, Fagus sylvatica and Picea abies and January temperature (Tjan has remained stable over the past 10,000 years.We used an extended data-set of fossil pollen records over Europe to reconstruct spatial variation in Tjan values for each 1,000-year time slice between 10,000 and 3,000 years BP (before present.We evaluated the relationships between the occurrences of the three species at each time slice and the spatially interpolated Tjan values, and compared these to their modern temperature ranges.Our results reveal that Fagus sylvatica and Picea abies experienced Tjan ranges during the Holocene that differ from those of the present, while Abies alba occurred over a Tjan range that is comparable to its modern one.Our data suggest the need for re-evaluation of the assumption of stable climate tolerances at a scale of several thousand years. The temperature range instability in our observed data independently validates similar results based exclusively on modelled Holocene temperatures. Our study complements previous studies that used modelled data by identifying variation in frequencies of occurrence of populations within the limits of suitable climate. However, substantial changes that were observed in the realized thermal niches over the Holocene tend to suggest that predicting future species distributions should not solely be based on modern realized niches, and needs to account for the past variation in the climate variables that drive species ranges.

  4. The temperature dependence of intermediate range oxygen-oxygen correlations in liquid water

    International Nuclear Information System (INIS)

    Schlesinger, Daniel; Pettersson, Lars G. M.; Wikfeldt, K. Thor; Skinner, Lawrie B.; Benmore, Chris J.; Nilsson, Anders

    2016-01-01

    We analyze the recent temperature dependent oxygen-oxygen pair-distribution functions from experimental high-precision x-ray diffraction data of bulk water by Skinner et al. [J. Chem. Phys. 141, 214507 (2014)] with particular focus on the intermediate range where small, but significant, correlations are found out to 17 Å. The second peak in the pair-distribution function at 4.5 Å is connected to tetrahedral coordination and was shown by Skinner et al. to change behavior with temperature below the temperature of minimum isothermal compressibility. Here we show that this is associated also with a peak growing at 11 Å which strongly indicates a collective character of fluctuations leading to the enhanced compressibility at lower temperatures. We note that the peak at ∼13.2 Å exhibits a temperature dependence similar to that of the density with a maximum close to 277 K or 4 °C. We analyze simulations of the TIP4P/2005 water model in the same manner and find excellent agreement between simulations and experiment albeit with a temperature shift of ∼20 K.

  5. Wide-range vortex shedding flowmeter for high-temperature helium gas

    Energy Technology Data Exchange (ETDEWEB)

    Baker, S.P.; Herndon, P.G.; Ennis, R.M. Jr.

    1983-01-01

    The existing design of a commercially available vortex shedding flowmeter (VSFM) was modified and optimized to produce three 4-in. and one 6-in. high-performance VSFMs for measuring helium flow in a gas-cooled fast reactor (GCFR) test loop. The project was undertaken because of the significant economic and performance advantages to be realized by using a single flowmeter capable of covering the 166:1 flow range (at 350/sup 0/C and 45:1 pressure range) of the tests. A detailed calibration in air and helium at the Colorado Engineering Experiment Station showed an accuracy of +-1% of reading for a 100:1 helium flow range and +-1.75% of reading for a 288:1 flow range in both helium and air. At an extended gas temperature of 450/sup 0/C, water cooling was necessary for reliable flowmeter operation.

  6. Reassessing changes in diurnal temperature range: A new data set and characterization of data biases

    Science.gov (United States)

    Thorne, P. W.; Menne, M. J.; Williams, C. N.; Rennie, J. J.; Lawrimore, J. H.; Vose, R. S.; Peterson, T. C.; Durre, I.; Davy, R.; Esau, I.; Klein-Tank, A. M. G.; Merlone, A.

    2016-05-01

    It has been a decade since changes in diurnal temperature range (DTR) globally have been assessed in a stand-alone data analysis. The present study takes advantage of substantively improved basic data holdings arising from the International Surface Temperature Initiative's databank effort and applies the National Centers for Environmental Information's automated pairwise homogeneity assessment algorithm to reassess DTR records. It is found that breakpoints are more prevalent in DTR than other temperature elements and that the resulting adjustments have a broader distribution. This strongly implies that there is an overarching tendency, across the global meteorological networks, for nonclimatic artifacts to impart either random or anticorrelated rather than correlated biases in maximum and minimum temperature series. Future homogenization efforts would likely benefit from simultaneous consideration of DTR and maximum and minimum temperatures, in addition to average temperatures. Estimates of change in DTR are relatively insensitive to whether adjustments are calculated directly or inferred from adjustments returned for the maximum and minimum temperature series. The homogenized series exhibit a reduction in DTR since the midtwentieth century globally (-0.044 K/decade). Adjustments serve to approximately halve the long-term global reduction in DTR in the basic "raw" data. Most of the estimated DTR reduction occurred over 1960-1980. In several regions DTR has apparently increased over 1979-2012, while globally it has exhibited very little change (-0.016 K/decade). Estimated changes in DTR are an order of magnitude smaller than in maximum and minimum temperatures, which have both been increasing rapidly on multidecadal timescales (0.186 K/decade and 0.236 K/decade, respectively, since the midtwentieth century).

  7. Construction of stess-strain curves for brittle materials by indentation in a wide temperature range

    Directory of Open Access Journals (Sweden)

    Milman Yu.V.

    2007-01-01

    Full Text Available A test method procedure for constructing stress-strain curves by indentation of brittle and low plastic materials under temperature ranging from 20 to 900°C was developed recently by Yu. Milman, B. Galanov et al. According to this test method procedure stress-strain curves σ - Є for Si, Ge, SiC, TiB2 and WC/Co hard alloy were constructed in the above temperature region and mechanical parameters such as elastic point, σe, yield stress, σs, etc. were extracted by using the measurement results obtained by a set of trihedral pyramid indenters with different angles at the tip, γ1, ranging from 45 to 85°C.

  8. Memory effects, two color percolation, and the temperature dependence of Mott variable-range hopping

    Science.gov (United States)

    Agam, Oded; Aleiner, Igor L.

    2014-06-01

    There are three basic processes that determine hopping transport: (a) hopping between normally empty sites (i.e., having exponentially small occupation numbers at equilibrium), (b) hopping between normally occupied sites, and (c) transitions between normally occupied and unoccupied sites. In conventional theories all these processes are considered Markovian and the correlations of occupation numbers of different sites are believed to be small (i.e., not exponential in temperature). We show that, contrary to this belief, memory effects suppress the processes of type (c) and manifest themselves in a subleading exponential temperature dependence of the variable-range hopping conductivity. This temperature dependence originates from the property that sites of type (a) and (b) form two independent resistor networks that are weakly coupled to each other by processes of type (c). This leads to a two-color percolation problem which we solve in the critical region.

  9. Elevational ranges of birds on a tropical montane gradient lag behind warming temperatures.

    Directory of Open Access Journals (Sweden)

    German Forero-Medina

    Full Text Available BACKGROUND: Species may respond to a warming climate by moving to higher latitudes or elevations. Shifts in geographic ranges are common responses in temperate regions. For the tropics, latitudinal temperature gradients are shallow; the only escape for species may be to move to higher elevations. There are few data to suggest that they do. Yet, the greatest loss of species from climate disruption may be for tropical montane species. METHODOLOGY/PRINCIPAL FINDINGS: We repeat a historical transect in Peru and find an average upward shift of 49 m for 55 bird species over a 41 year interval. This shift is significantly upward, but also significantly smaller than the 152 m one expects from warming in the region. To estimate the expected shift in elevation we first determined the magnitude of warming in the locality from historical data. Then we used the temperature lapse rate to infer the required shift in altitude to compensate for warming. The range shifts in elevation were similar across different trophic guilds. CONCLUSIONS: Endothermy may provide birds with some flexibility to temperature changes and allow them to move less than expected. Instead of being directly dependent on temperature, birds may be responding to gradual changes in the nature of the habitat or availability of food resources, and presence of competitors. If so, this has important implications for estimates of mountaintop extinctions from climate change.

  10. The temperature dependence of the BK channel activity - kinetics, thermodynamics, and long-range correlations.

    Science.gov (United States)

    Wawrzkiewicz-Jałowiecka, Agata; Dworakowska, Beata; Grzywna, Zbigniew J

    2017-10-01

    Large-conductance, voltage dependent, Ca 2+ -activated potassium channels (BK) are transmembrane proteins that regulate many biological processes by controlling potassium flow across cell membranes. Here, we investigate to what extent temperature (in the range of 17-37°C with ΔT=5°C step) is a regulating parameter of kinetic properties of the channel gating and memory effect in the series of dwell-time series of subsequent channel's states, at membrane depolarization and hyperpolarization. The obtained results indicate that temperature affects strongly the BK channels' gating, but, counterintuitively, it exerts no effect on the long-range correlations, as measured by the Hurst coefficient. Quantitative differences between dependencies of appropriate channel's characteristics on temperature are evident for different regimes of voltage. Examining the characteristics of BK channel activity as a function of temperature allows to estimate the net activation energy (E act ) and changes of thermodynamic parameters (ΔH, ΔS, ΔG) by channel opening. Larger E act corresponds to the channel activity at membrane hyperpolarization. The analysis of entropy and enthalpy changes of closed to open channel's transition suggest the entropy-driven nature of the increase of open state probability during voltage activation and supports the hypothesis about the voltage-dependent geometry of the channel vestibule. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Modelling the effect of temperature on the range expansion of species by reaction-diffusion equations.

    Science.gov (United States)

    Richter, Otto; Moenickes, Sylvia; Suhling, Frank

    2012-02-01

    The spatial dynamics of range expansion is studied in dependence of temperature. The main elements population dynamics, competition and dispersal are combined in a coherent approach based on a system of coupled partial differential equations of the reaction-diffusion type. The nonlinear reaction terms comprise population dynamic models with temperature dependent reproduction rates subject to an Allee effect and mutual competition. The effect of temperature on travelling wave solutions is investigated for a one dimensional model version. One main result is the importance of the Allee effect for the crossing of regions with unsuitable habitats. The nonlinearities of the interaction terms give rise to a richness of spatio-temporal dynamic patterns. In two dimensions, the resulting non-linear initial boundary value problems are solved over geometries of heterogeneous landscapes. Geo referenced model parameters such as mean temperature and elevation are imported into the finite element tool COMSOL Multiphysics from a geographical information system. The model is applied to the range expansion of species at the scale of middle Europe. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Effects of reproductive status and high ambient temperatures on the body temperature of a free-ranging basoendotherm.

    Science.gov (United States)

    Levesque, Danielle L; Lobban, Kerileigh D; Lovegrove, Barry G

    2014-12-01

    Tenrecs (Order Afrosoricida) exhibit some of the lowest body temperatures (T b) of any eutherian mammal. They also have a high level of variability in both active and resting T bs and, at least in cool temperatures in captivity, frequently employ both short- and long-term torpor. The use of heterothermy by captive animals is, however, generally reduced during gestation and lactation. We present data long-term T b recordings collected from free-ranging S. setosus over the course of two reproductive seasons. In general, reproductive females had slightly higher (~32 °C) and less variable T b, whereas non-reproductive females and males showed both a higher propensity for torpor as well as lower (~30.5 °C) and more variable rest-phase T bs. Torpor expression defined using traditional means (using a threshold or cut-off T b) was much lower than predicted based on the high degree of heterothermy in captive tenrecs. However, torpor defined in this manner is likely to be underestimated in habitats where ambient temperature is close to T b. Our results caution against inferring metabolic states from T b alone and lend support to the recent call to define torpor in free-ranging animals based on mechanistic and not descriptive variables. In addition, lower variability in T b observed during gestation and lactation confirms that homeothermy is essential for reproduction in this species and probably for basoendothermic mammals in general. The relatively low costs of maintaining homeothermy in a sub-tropical environment might help shed light on how homeothermy could have evolved incrementally from an ancestral heterothermic condition.

  13. Investigation of Breakpoint and Trend of Daily Air Temperature Range for Mashhad, Iran

    Directory of Open Access Journals (Sweden)

    shideh shams

    2017-01-01

    Full Text Available Introduction: Air temperature as an important climatic factor can influence variability and distribution of other climatic parameters. Therefore, tracking the changes in air temperature is a popular procedure in climate change studies.. According to the national academy in the last decade, global temperature has raised 0.4 to 0.8⁰C. Instrumental records show that, with the exception of 1998, the 10 warmest year (during the last 150 years, occurred since 2000, and 2014 was the warmest year. Investigation of maximum and minimum air temperature temporal trend indicates that these two parameters behave differently over time. It has been shown that the minimum air temperature raises noticeably more than the maximum air temperature, which causes a reduction in the difference of maximum and minimum daily air temperature (daily temperature range, DTR. There are several factors that have an influence on reducing DTR such as: Urban development, farms’ irrigation and desertification. It has been shown that DTR reduction occurs mostly during winter and is less frequent during summer, which shows the season’s effect on the temperature trend. Considering the significant effects of the climatological factors on economic and agricultural management issues, the aim of this study is to investigate daily air temperature range for yearly, seasonal and monthly time scales, using available statistical methods. Materials and Methods: Daily maximum and minimum air temperature records (from 1950 to 2010 were obtained from Mashhad Meteorological Organization. In order to control the quality of daily Tmax and Tmin data, four different types of quality controls were applied. First of all, gross errors were checked. In this step maximum and minimum air temperature data exceeding unlikely air temperature values, were eliminated from data series. Second, data tolerance was checked by searching for periods longer than a certain number of consecutive days with exactly the

  14. Spring leaf phenology and the diurnal temperature range in a temperate maple forest.

    Science.gov (United States)

    Hanes, Jonathan M

    2014-03-01

    Spring leaf phenology in temperate climates is intricately related to numerous aspects of the lower atmosphere [e.g., surface energy balance, carbon flux, humidity, the diurnal temperature range (DTR)]. To further develop and improve the accuracy of ecosystem and climate models, additional investigations of the specific nature of the relationships between spring leaf phenology and various ecosystem and climate processes are required in different environments. This study used visual observations of maple leaf phenology, below-canopy light intensities, and micrometeorological data collected during the spring seasons of 2008, 2009, and 2010 to examine the potential influence of leaf phenology on a seasonal transition in the trend of the DTR. The timing of a reversal in the DTR trend occurred near the time when the leaves were unfolding and expanding. The results suggest that the spring decline in the DTR can be attributed primarily to the effect of canopy closure on daily maximum temperature. These findings improve our understanding of the relationship between leaf phenology and the diurnal temperature range in temperate maple forests during the spring. They also demonstrate the necessity of incorporating accurate phenological data into ecosystem and climate models and warrant a careful examination of the extent to which canopy phenology is currently incorporated into existing models.

  15. A low-noise wide dynamic range CMOS image sensor with low and high temperatures resistance

    Science.gov (United States)

    Mizobuchi, Koichi; Adachi, Satoru; Tejada, Jose; Oshikubo, Hiromichi; Akahane, Nana; Sugawa, Shigetoshi

    2008-02-01

    A temperature-resistant 1/3 inch SVGA (800×600 pixels) 5.6 μm pixel pitch wide-dynamic-range (WDR) CMOS image sensor has been developed using a lateral-over-flow-integration-capacitor (LOFIC) in a pixel. The sensor chips are fabricated through 0.18 μm 2P3M process with totally optimized front-end-of-line (FEOL) & back-end-of-line (BEOL) for a lower dark current. By implementing a low electrical field potential design for photodiodes, reducing damages, recovering crystal defects and terminating interface states in the FEOL+BEOL, the dark current is improved to 12 e - /pixel-sec at 60 deg.C with 50% reduction from the previous very-low-dark-current (VLDC) FEOL and its contribution to the temporal noise is improved. Furthermore, design optimizations of the readout circuits, especially a signal-and noise-hold circuit and a programmable-gain-amplifier (PGA) are also implemented. The measured temporal noise is 2.4 e -rms at 60 fps (:36 MHz operation). The dynamic-range (DR) is extended to 100 dB with 237 ke - full well capacity. In order to secure the temperature-resistance, the sensor chip also receives both an inorganic cap onto micro lens and a metal hermetic seal package assembly. Image samples at low & high temperatures show significant improvement in image qualities.

  16. Defining the temperature range for cooking with extra virgin olive oil using Raman spectroscopy

    Science.gov (United States)

    Ahmad, Naveed; Saleem, M.; Ali, H.; Bilal, M.; Khan, Saranjam; Ullah, Rahat; Ahmed, M.; Mahmood, S.

    2017-09-01

    Using the potential of Raman spectroscopy, new findings regarding the effects of heating on extra virgin olive oil (EVOO) during frying/cooking are presented. A temperature range from 140 to 150 °C has been defined within which EVOO can be used for cooking/frying without much loss of its natural molecular composition. Raman spectra from the EVOO samples were recorded using an excitation laser at 785 nm in the range from 540 to 1800 cm-1. Due to heating, prominent variations in intensity are observed at Raman bands from 540 to 770 cm-1, 790 to 1170 cm-1 and 1267 and 1302 cm-1. The Raman bands at 1267 and 1302 cm-1 represent cis unsaturated fats and their ratio is used to investigate the effects of temperature on the molecular composition of EVOO. In addition, principal component analysis has been applied on all the groups of data to classify the heated EVOO samples at different temperatures and for different times. In addition, it has been found that use of EVOO for frying twice does not have any prominent effect on its molecular composition.

  17. Downstream changes in spring-fed stream invertebrate communities: the effect of increased temperature range?

    Directory of Open Access Journals (Sweden)

    Russell G. DEATH

    2011-09-01

    Full Text Available Reduced thermal amplitude has been highlighted as a limiting factor for aquatic invertebrate diversity in springs. Moving downstream water temperature range increases and invertebrate richness is expected to change accordingly. In the present study temperature patterns were investigated in seven spring-fed streams, between April 2001 and November 2002, and compared to five run-off-fed streams to assess the degree of crenic temperature constancy. Temperature and physico-chemical characteristics of the water, and food resource levels were measured, and the invertebrate fauna collected at 4 distances (0, 100, 500 m and 1 km from seven springs in the North and South Islands of New Zealand. Temperature variability was greater for run-off-fed streams than for springs, and increased in the spring-fed streams with distance from the source. Periphyton and physico-chemical characteristics of the water did not change markedly over the 1 km studied, with the exception of water velocity and organic matter biomass, which increased and decreased, respectively. The rate of increase in temperature amplitude differed greatly for the studied springs, probably being affected by flow, altitude, and the number and type of tributaries (i.e., spring- or run-off-fed joining the spring-fed stream channel. Longitudinal changes in the number and evenness of invertebrate taxa were positively correlated to thermal amplitude (rs = 0.8. Moving downstream, invertebrate communities progressively incorporated taxa with higher mobility and taxa more common in nearby run-off-fed streams. Chironomids and non-insect taxa were denser at the sources. Chironomid larvae also numerically dominated communities 100 and 500 m downstream from the sources, together with Pycnocentria spp. and Zelolessica spp., while taxa such as Hydora sp. and Hydraenidae beetles, the mayflies Deleatidium spp. and Coloburiscus humeralis, and the Trichoptera Pycnocentrodes spp., all had greater abundances 1 km

  18. Modifiers of diurnal temperature range and mortality association in six Korean cities

    Science.gov (United States)

    Lim, Youn-Hee; Park, Ae Kyung; Kim, Ho

    2012-01-01

    Rapid temperature changes within a single day may be critical for populations vulnerable to thermal stress who have difficulty adjusting themselves behaviorally and physiologically. We hypothesized that diurnal temperature range (DTR) is associated with mortality, and that this association is modified by season and socioeconomic status (SES). We evaluated meteorological and mortality data from six metropolitan areas in Korea from 1992 to 2007. We applied generalized linear models (GLM) for quantifying the estimated effects of DTR on mortality after adjusting for mean temperature, dew point temperature, day of the week, and seasonal and long-term trends. Most areas showed a linear DTR-mortality relationship, with evidence of increasing mortality with increasing DTR. Deaths among the elderly (75 years or older), females, the less educated, and the non-hospital population were associated more strongly with DTR than with the corresponding categories. DTR was the greatest threat to vulnerable study populations, with greater influence in the fall season. DTR was found to be a predictor of mortality, and this relationship was modified by season and SES.

  19. Temperature Range for Metasomatism at the Bakalskoe Siderite Deposits with Use of Geochemical Data

    Directory of Open Access Journals (Sweden)

    M. T. Krupenin

    2017-06-01

    Full Text Available The data obtained with the quantitative microprobe ankerite–siderite composition analysis of seven samples from the different parts of Bakalskoe field showed that the wallrock ankerites in the western and central parts of the ore field differ in average concentrations of FeCO 3 (respectively 14.21 and 20.84 wt.%. However, there is no significant difference in composition of siderites. The calculation of the Mg-Fe metasomatism temperatures based on ankerite-siderite and ankerite-breinerite geothermometers showed the close agreement of the values of both methods at temperatures of 250 °C and above. The average temperatures of siderite metasomatism in the central part of the Bakalskoe ore field are in range 250-270 ° C, and, in the peripheral part, the determined temperature does not exceed 190-220 ° C. These values do not depend on the position of the siderite deposits in stratigraphic level of the Bakalskaya Suite.

  20. Host range of Phytophthora parsiana: a new high temperature pathogen of woody plants

    Directory of Open Access Journals (Sweden)

    Somieh HAJEBRAHIMI

    2011-05-01

    Full Text Available Normal 0 14 false false false IT ZH-TW X-NONE MicrosoftInternetExplorer4 Among several Phytophthora spp. reported previously from Pistacia vera in Iran, a high temperature species recently identified as P. parsiana (formerly known as high temperature P. cryptogea is becoming important in woody plants, including P. vera. The host range of this newly recognised species, including both annual and perennial plants, is reported here. The pathogen infected 4–5 month-old glasshouse grown seedlings of P. vera, Ficus carica, Malus pumila and Prunus dulcis, and detached stems of 23 woody plants collected during dormant and growing seasons. Nineteen field and vegetable crops and 17 weed species were not infected by  P. parsiana in these pathogenicity assays.

  1. The enthalpy of solid scandium in the temperature range 406 - 1812 K

    International Nuclear Information System (INIS)

    Lyapunov, K.M.; Baginskij, A.V.; Stankus, S.V.

    2001-01-01

    Enthalpy of pure scandium was measured on massive calorimeter in the range from 406 to 1812 K by mixing method. The enthalpy of face centered close cubic lattice - body centered cubic lattice transformation is equal to ΔH t 4068 J/mol. Obtained value within the limits of error is compatible with the results given earlier (4009 J/mol). The dependence of the middle specific heat of scandium C p (T) on the temperature was shown in correlation with the results of other works. The results of the conducted experiments reinforce the conclusion made earlier about an absence (or a little) in the decomposition of an anharmonic component of the oscillation specific heat of scandium C p a (T) members proportional to the first or the second degrees of temperature [ru

  2. A new method for achieving enhanced dielectric response over a wide temperature range.

    Science.gov (United States)

    Maurya, Deepam; Sun, Fu-Chang; Alpay, S Pamir; Priya, Shashank

    2015-10-19

    We report a novel approach for achieving high dielectric response over a wide temperature range. In this approach, multilayer ceramic heterostructures with constituent compositions having strategically tuned Curie points (T(C)) were designed and integrated with varying electrical connectivity. Interestingly, these multilayer structures exhibited different dielectric behavior in series and parallel configuration due to variations in electrical boundary conditions resulting in the differences in the strength of the electrostatic coupling. The results are explained using nonlinear thermodynamic model taking into account electrostatic interlayer interaction. We believe that present work will have huge significance in design of high performance ceramic capacitors.

  3. Biaxial creep deformation of Zircaloy-4 in the high alpha phase temperature range

    International Nuclear Information System (INIS)

    Donaldson, A.T.; Horwood, R.A.; Healey, T.

    1983-01-01

    The ballooning response of Zircaloy-4 fuel tubes during a postulated loss-of-coolant accident may be calculated from a knowledge of the thermal environment of the rods and the creep deformation characteristics of the cladding. In support of such calculations biaxial creep studies have been performed on fuel tubes supplied by Westinghouse, Wolverine and Sandvik of temperatures in the alpha phase range. This paper presents the results of an investigation of their respective creep behaviour which has resulted in the formulation of equations for use in LOCA fuel ballooning codes. (author)

  4. Retrieval and Mapping of Soil Texture Based on Land Surface Diurnal Temperature Range Data from MODIS.

    Science.gov (United States)

    Wang, De-Cai; Zhang, Gan-Lin; Zhao, Ming-Song; Pan, Xian-Zhang; Zhao, Yu-Guo; Li, De-Cheng; Macmillan, Bob

    2015-01-01

    Numerous studies have investigated the direct retrieval of soil properties, including soil texture, using remotely sensed images. However, few have considered how soil properties influence dynamic changes in remote images or how soil processes affect the characteristics of the spectrum. This study investigated a new method for mapping regional soil texture based on the hypothesis that the rate of change of land surface temperature is related to soil texture, given the assumption of similar starting soil moisture conditions. The study area was a typical flat area in the Yangtze-Huai River Plain, East China. We used the widely available land surface temperature product of MODIS as the main data source. We analyzed the relationships between the content of different particle soil size fractions at the soil surface and land surface day temperature, night temperature and diurnal temperature range (DTR) during three selected time periods. These periods occurred after rainfalls and between the previous harvest and the subsequent autumn sowing in 2004, 2007 and 2008. Then, linear regression models were developed between the land surface DTR and sand (> 0.05 mm), clay (soil texture. The spatial distribution of soil texture from the studied area was mapped based on the model with the minimum RMSE. A validation dataset produced error estimates for the predicted maps of sand, clay and physical clay, expressed as RMSE of 10.69%, 4.57%, and 12.99%, respectively. The absolute error of the predictions is largely influenced by variations in land cover. Additionally, the maps produced by the models illustrate the natural spatial continuity of soil texture. This study demonstrates the potential for digitally mapping regional soil texture variations in flat areas using readily available MODIS data.

  5. Retrieval and Mapping of Soil Texture Based on Land Surface Diurnal Temperature Range Data from MODIS

    Science.gov (United States)

    Wang, De-Cai; Zhang, Gan-Lin; Zhao, Ming-Song; Pan, Xian-Zhang; Zhao, Yu-Guo; Li, De-Cheng; Macmillan, Bob

    2015-01-01

    Numerous studies have investigated the direct retrieval of soil properties, including soil texture, using remotely sensed images. However, few have considered how soil properties influence dynamic changes in remote images or how soil processes affect the characteristics of the spectrum. This study investigated a new method for mapping regional soil texture based on the hypothesis that the rate of change of land surface temperature is related to soil texture, given the assumption of similar starting soil moisture conditions. The study area was a typical flat area in the Yangtze-Huai River Plain, East China. We used the widely available land surface temperature product of MODIS as the main data source. We analyzed the relationships between the content of different particle soil size fractions at the soil surface and land surface day temperature, night temperature and diurnal temperature range (DTR) during three selected time periods. These periods occurred after rainfalls and between the previous harvest and the subsequent autumn sowing in 2004, 2007 and 2008. Then, linear regression models were developed between the land surface DTR and sand (> 0.05 mm), clay (estimate soil texture. The spatial distribution of soil texture from the studied area was mapped based on the model with the minimum RMSE. A validation dataset produced error estimates for the predicted maps of sand, clay and physical clay, expressed as RMSE of 10.69%, 4.57%, and 12.99%, respectively. The absolute error of the predictions is largely influenced by variations in land cover. Additionally, the maps produced by the models illustrate the natural spatial continuity of soil texture. This study demonstrates the potential for digitally mapping regional soil texture variations in flat areas using readily available MODIS data. PMID:26090852

  6. Standard test method for determination of reference temperature, to, for ferritic steels in the transition range

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2011-01-01

    1.1 This test method covers the determination of a reference temperature, To, which characterizes the fracture toughness of ferritic steels that experience onset of cleavage cracking at elastic, or elastic-plastic KJc instabilities, or both. The specific types of ferritic steels (3.2.1) covered are those with yield strengths ranging from 275 to 825 MPa (40 to 120 ksi) and weld metals, after stress-relief annealing, that have 10 % or less strength mismatch relative to that of the base metal. 1.2 The specimens covered are fatigue precracked single-edge notched bend bars, SE(B), and standard or disk-shaped compact tension specimens, C(T) or DC(T). A range of specimen sizes with proportional dimensions is recommended. The dimension on which the proportionality is based is specimen thickness. 1.3 Median KJc values tend to vary with the specimen type at a given test temperature, presumably due to constraint differences among the allowable test specimens in 1.2. The degree of KJc variability among specimen types i...

  7. Features of austenite formation in low-carbon steel upon heating in the intercritical temperature range

    Science.gov (United States)

    Panov, D. O.; Smirnov, A. I.

    2017-11-01

    The features of austenite formation upon continuous heating of low-carbon steel at the rates of 90-0.15 K/s in the intercritical temperature range (ICTR) have been studied. It has been found that, in the initially high-tempered, initially quenched, and initially cold-deformed steel, the α → γ transition in the ICTR consists of three stages. The thermokinetic diagrams of the austenite formation with the indication of the positions of the critical points Ac 1 and Ac 3 and also of the temperature ranges of the development of each identified stage of the α → γ transformation have been constructed. A complex of structural studies has been carried out, and a scheme of the austenite formation upon continuous heating at a rate of 90 K/s in the ICTR for the initially high-tempered steel, initially quenched steel, and initially cold-deformed low-carbon steel has been suggested, which reflects all stages of this process.

  8. Influence of the atomic structure of crystal surfaces on the surface diffusion in medium temperature range

    International Nuclear Information System (INIS)

    Cousty, J.P.

    1981-12-01

    In this work, we have studied the influence of atomic structure of crystal surface on surface self-diffusion in the medium temperature range. Two ways are followed. First, we have measured, using a radiotracer method, the self-diffusion coefficient at 820 K (0.6 T melting) on copper surfaces both the structure and the cleanliness of which were stable during the experiment. We have shown that the interaction between mobile surface defects and steps can be studied through measurements of the anisotropy of surface self diffusion. Second, the behavior of an adatom and a surface vacancy is simulated via a molecular dynamics method, on several surfaces of a Lennard Jones crystal. An inventory of possible migration mechanisms of these surface defects has been drawn between 0.35 and 0.45 Tsub(m). The results obtained with both the methods point out the influence of the surface atomic structure in surface self-diffusion in the medium temperature range [fr

  9. Thermodynamic Properties of He Gas in the Temperature Range 4.2-10 K

    Science.gov (United States)

    Mosameh, S. M.; Sandouqa, A. S.; Ghassib, H. B.; Joudeh, B. R.

    2014-05-01

    The thermodynamic properties of He gas are investigated in the temperature-range 4.2-10 K, with special emphasis on the second virial coefficient in both the classical and quantum regimes. The main input in computing the quantum coefficient is the `effective' phase shifts. These are calculated within the framework of the Galitskii-Migdal-Feynman (GMF) formalism, using the HFDHE2 and Sposito potentials. The virial equation of state is constructed. Extensive calculations are carried out for the pressure-volume-temperature (P-V-T) behavior, as well as chemical potential, and nonideality of the system. The following results are obtained. First, the validity of the GMF formalism for the present system is demonstrated beyond any doubt. Second, the boiling point (phase-transition point) of He gas is determined from the P-V behavior using the virial equation of state, its value being closest than all previous results to the experimental value. Third, the chemical potential is evaluated from the quantum second virial coefficient. It is found that increases (becomes less negative) as the temperature decreases or the number density n increases. Further, shows no sensitivity to the differences between the potentials used up to n = 10 m. Finally, the compressibility Z is computed and discussed as a measure of the nonideality of the system.

  10. Direct measurement high resolution wide range extreme temperature optical sensor using an all-silicon carbide probe.

    Science.gov (United States)

    Sheikh, Mumtaz; Riza, Nabeel A

    2009-05-01

    We propose and demonstrate a temperature sensing method using an all-silicon carbide probe that combines wavelength-tuned signal processing for coarse measurements and classical Fabry-Perot etalon peak shift for fine measurements. This method gives direct unambiguous temperature measurements with a high temperature resolution over a wide temperature range. Specifically, temperature measurements from room temperature to 1000 degrees C are experimentally demonstrated with an estimated resolution varying from 0.66 degrees C at room temperature to 0.12 degrees C at 1000 degrees C. The proposed sensor has applications in next-generation greener gas turbines for power production.

  11. Neutral temperature range in incubators: performance of equipment in current use and new developments.

    Science.gov (United States)

    Libert, J P; Bach, V; Farges, G

    1997-01-01

    Low-birth-weight neonates should be nursed at thermoneutrality inside incubators. Thermoneutrality control is essential to enhance body growth and to reduce neonatal illnesses and mortality. Guidelines have been published to provide the thermoneutral range, but the recommendations did not always take into account all ambient and physiological parameters influencing thermoneutrality. In most marketed incubators, the heat supply is controlled through convective air flow (closed incubators) or through radiant power density (radiant warmer beds). The heating unit (on/off cycling or adjustable proportional control) is activated by an error signal calculated from the difference between a controlled temperature and a reference value preset by the clinician. The controlled variable can be either the incubator air or the skin temperature of the anterior abdominal region of the neonate. The neonate's size, thermal properties of the mattress and of incubator walls, air temperature and humidity, air velocity, incubator wall temperatures all influence the heat exchanges between the neonate and the surroundings, and, consequently, modify the obtention of thermoneutrality. Moreover, studies of the physiological mechanisms by which the neonate regulates body heat storage suggest that metabolic rate, behavior, vigilance level, nursing care, and heater control processes should also be taken into account. Little attention has been paid to these factors, and incubator performances are often disappointing. This article reviews the different factors that modify thermoneutral condition. An attempt is made to suggest new ways to design equipment incorporating these factors in algorithms controlling heater processes in order to reach the optimal thermal environment in which the neonate should be nursed.

  12. Evidence of both phenological and range shifts in birds in response to increasing temperature in Ireland

    Science.gov (United States)

    Donnelly, Alison; Cooney, Tom; Stirnemann, Rebecca; O'Halloran, John

    2010-05-01

    It is well established that the timing of arrival of long-distance migrant birds in spring is advancing throughout Europe and that this response is, at least in part, due to an increase in temperature in line with current global warming. In Ireland, we have seen a number of sub-Saharan species, such as, barn swallow (Hirundo rustica), northern wheatear (Oenanthe oenanthe) and sand martin (Riparia riparia) advance their arrival time over a 31-year period. In addition, a medium-distance winter migrant, the whooper swan (Cygnus cygnus), has significantly advanced its spring departure time from its wintering ground in Ireland. Furthermore, a number of species, such as the little egret (Egretta garzetta), more typically associated with a warmer climate than Ireland, was considered to be a ‘rare visitor' up to 1990 and has now begun to breed and to establish a population on the island. All of these phenological and range shifts have been correlated with various temperature variables. The consequences of early arrival at wintering and breeding grounds could result in increased fitness but only if an appropriate food resource is in adequate supply at the new earlier time. If temperatures continue to rise as predicted, the status of some bird species in Ireland may change from ‘rare' to ‘common' or from ‘visitor' to ‘resident' with a possible concurrent increase in population size. Equally, the opposite trend may occur, for birds that prefer cold temperatures, whereby we may see a decrease in population size followed by the loss of certain species.

  13. Laser parameters of a Fe : ZnSe crystal in the 85-255-K temperature range

    NARCIS (Netherlands)

    Voronov, AA; Kozlovskii, [No Value; Korostelin, YV; Podmar'kov, YP; Frolov, MP

    The temperature dependence of the efficiency of a laser based on a Fe:ZnSe crystal grown from the vapour phase by the free-growth method is studied in the 85-255-K temperature range. As the temperature was increased, the slope efficiency of the laser with respect to absorbed energy decreased from

  14. Effect of cutoff radius, long range interaction and temperature controller on thermodynamic properties of fluids: Methanol as an example

    Science.gov (United States)

    Obeidat, Abdalla; Jaradat, Adnan; Hamdan, Bushra; Abu-Ghazleh, Hind

    2018-04-01

    The best spherical cutoff radius, long range interaction and temperature controller were determined using surface tension, density, and diffusion coefficients of van Leeuwen and Smit methanol. A quite good range of cutoff radii from 0.75 to 1.45 nm has been studied on Coulomb cut-off and particle mesh Ewald (PME) long range interaction to determine the best cutoff radius and best long range interaction as well for four sets of temperature: 200, 230, 270 and 300 K. To determine the best temperature controller, the cutoff radius of 1.25 nm was fixed using PME long range interaction on calculating the above properties at low temperature range: 200-300 K.

  15. GlidCop {sup trademark} DSC properties in the temperature range of 20-350 C

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, R.R. [SCM Metal Products, Inc., Research Triangle Park, NC (United States); Troxell, J.D. [SCM Metal Products, Inc., Research Triangle Park, NC (United States); Nadkarni, A.V. [SCM Metal Products, Inc., Research Triangle Park, NC (United States)

    1996-10-01

    GlidCop {sup trademark} AL-25 LOX-80 grade plates manufactured by processes relevant to ITER first wall copper alloy requirements were tested in the temperature range of 20-350 C. Plate manufacturing methods included hot isostatic pressing (HIP), extrusion (EXT), and extrusion followed by cross-rolling (EXT+XROLL). Tests that were performed included tensile, fracture toughness, impact toughness, and creep. The EXT+XROLL plate was found to have higher total elongation, reduction of area, and fracture toughness values than the EXT and HIP plates. All three processes had similar ultimate tensile and 0.2% yield strengths. The HIP material exhibited a lower creep rate than EXT+XROLL. The EXT and the EXT+XROLL plates had similar impact toughness values, which were higher than the HIP plate. Overall, the EXT+XROLL plate had the best combination of properties of the three processes examined. (orig.).

  16. Oxidation kinetics of zircaloy-4 in the temperature range correspondent to alpha phase

    International Nuclear Information System (INIS)

    Medeiros, L.F.

    1975-12-01

    Oxidation kinetics of Zry-4 in the alpha phase is isothermally studied in the temperature range from 600 0 C to 800 0 C, by continuous and discontinuous gravimetric methods. The total mass gain during the oxidation takes place by two distinct ways: oxide formation and solid solution formation. The first one has been studied by microscopy: the latter by microhardness. The oxygen diffusion coefficients in the zirconium are experimentally determined by microhardness measurements and are compared with those obtained by the oxide layer thickness and by oxygen mass in the oxide. The oxygen diffusion coefficients in the oxide are obtained too by oxide layer thickness and by oxygen diffusivities in the alpha phase and compared with literature. (author)

  17. Diurnal temperature range and short-term mortality in large US communities

    Science.gov (United States)

    Lim, Youn-Hee; Reid, Colleen E.; Mann, Jennifer K.; Jerrett, Michael; Kim, Ho

    2015-09-01

    Research has shown that diurnal temperature range (DTR) is significantly associated with mortality and morbidity in regions of Asia; however, few studies have been conducted in other regions such as North America. Thus, we examined DTR effects on mortality in the USA. We used mortality and environmental data from the National Morbidity Mortality Air Pollution Study (NMMAPS). The data are daily mortality, air pollution, and temperature statistics from 95 large US communities collected between 1987 and 2000. To assess community-specific DTR effects on mortality, we used Poisson generalized linear models allowing for over-dispersion. After assessing community-specific DTR effects on mortality, we estimated region- and age-specific effects of DTR using two-level normal independent sampling estimation. We found a significant increase of 0.27 % [95 % confidence intervals (CI), 0.24-0.30 %] in nonaccidental mortality across 95 communities in the USA associated with a 1 °C increase in DTR, controlling for apparent temperature, day of the week, and time trend. This overall effect was driven mainly by effects of DTR on cardiovascular and respiratory mortality in the elderly: Mortality in the above 65 age group increased by 0.39 % (95 % CI, 0.33-0.44 %) and 0.33 % (95 % CI, 0.22-0.44 %), respectively. We found some evidence of regional differences in the effects of DTR on nonaccidental mortality with the highest effects in Southern California [0.31 % (95 % CI, 0.21-0.42 %)] and smallest effects in the Northwest and Upper Midwest regions [0.22 % (95 % CI, 0.11-0.33 %) and 0.22 % (95 % CI, 0.07-0.37 %), respectively]. These results indicate a statistically significant association between DTR and mortality on average for 95 large US communities. The findings indicate that DTR impacts on nonaccidental and cardiovascular-related mortality in most US regions and the elderly population was most vulnerable to the effects of DTR.

  18. Interlot variations of transition temperature range and force delivery in copper-nickel-titanium orthodontic wires.

    Science.gov (United States)

    Pompei-Reynolds, Renée C; Kanavakis, Georgios

    2014-08-01

    The manufacturing process for copper-nickel-titanium archwires is technique sensitive. The primary aim of this investigation was to examine the interlot consistency of the mechanical properties of copper-nickel-titanium wires from 2 manufacturers. Wires of 2 sizes (0.016 and 0.016 × 0.022 in) and 3 advertised austenite finish temperatures (27°C, 35°C, and 40°C) from 2 manufacturers were tested for transition temperature ranges and force delivery using differential scanning calorimetry and the 3-point bend test, respectively. Variations of these properties were analyzed for statistical significance by calculating the F statistic for equality of variances for transition temperature and force delivery in each group of wires. All statistical analyses were performed at the 0.05 level of significance. Statistically significant interlot variations in austenite finish were found for the 0.016 in/27°C (P = 0.041) and 0.016 × 0.022 in/35°C (P = 0.048) wire categories, and in austenite start for the 0.016 × 0.022 in/35°C wire category (P = 0.01). In addition, significant variations in force delivery were found between the 2 manufacturers for the 0.016 in/27°C (P = 0.002), 0.016 in/35.0°C (P = 0.049), and 0.016 × 0.022 in/35°C (P = 0.031) wires. Orthodontic wires of the same material, dimension, and manufacturer but from different production lots do not always have similar mechanical properties. Clinicians should be aware that copper-nickel-titanium wires might not always deliver the expected force, even when they come from the same manufacturer, because of interlot variations in the performance of the material. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  19. Acute effects of diurnal temperature range on mortality in 8 Chinese cities.

    Science.gov (United States)

    Zhou, Xiaodan; Zhao, Ang; Meng, Xia; Chen, Renjie; Kuang, Xingya; Duan, Xiaoli; Kan, Haidong

    2014-09-15

    Diurnal temperature range (DTR) is a meteorological indicator closely associated with global climate change. There have been no multicity studies in China addressing the DTR-related health impact. We hypothesized that an increase of DTR is associated with higher daily mortality with a potential lag of effect, and investigated the acute effects of DTR on total, cardiovascular, and respiratory mortality in 8 large Chinese cities from 2001 to 2010. We first calculated city-specific effect of DTR in the full year, the cool season (November to the next April) and the warm season (May to October) separately using a semi-parametric generalized additive model; then we pooled the city-specific estimates with meta analysis. After adjusting for long-term and seasonal trends, temperature, relative humidity and air pollution levels, we found statistically significant associations between DTR and daily mortality, especially in cool seasons. A 1 °C increment of DTR on lag-day 1 corresponded to a 0.42% (95% CI, 0.14 to 0.70) increase in total non-accidental mortality, 0.45% (95% CI, 0.26 to 0.65) increase in cardiovascular mortality, and a 0.76% (95% CI, 0.24 to 1.29) increase in respiratory mortality in cool seasons. Deaths among females and elderly (≥ 65 years) were more strongly associated with DTR than among males and younger people (climate policies in the country. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Solubility of hydrogen in water in a broad temperature and pressure range

    International Nuclear Information System (INIS)

    Baranenko, V.I.; Kirov, V.S.

    1989-01-01

    In the coolant of water-water reactors, as a result of radiolytic decomposition of water and chemical additives (hydrazine and ammonia) and saturation of the make-up water of the first loop with free hydrogen in order to suppress radiolysis, 30-60 ml/kg of hydrogen is present in normal conditions. On being released from the water, it is free to accumulate in micropores of the metals, resulting in hydrogen embrittlement; gas accumulates in stagnant zones, with deterioration in heat transfer in the first loop and corresponding difficulty in the use of the reactor and the whole reactor loop. To determine the amount of free hydrogen and hydrogen dissolved in water in different elements of the first loop, it is necessary to know the limiting solubility of hydrogen in water at different temperatures and pressures, and also to have the corresponding theoretical dependences. The experimental data on the solubility of hydrogen in water are nonsystematic and do not cover the parameter ranges of modern nuclear power plants (P = 10-30 MPa, T = 260-370C). Therefore, the aim of the present work is to establish a well-founded method of calculating the limiting solubility of hydrogen in water and, on this basis, to compile tables of the limiting solubility of hydrogen in water at pressures 0.1-50 MPa and temperatures 0-370C

  1. Does a weekend effect in diurnal temperature range exist in the eastern and central Tibetan Plateau?

    International Nuclear Information System (INIS)

    You Qinglong; Kang Shichang; Xu Yanwei; Huang Jie; Fluegel, Wolfgang-Albert; Sanchez-Lorenzo, Arturo; Yan Yuping

    2009-01-01

    The 'weekend effect' method (defined here as the average for Saturday through Monday minus the average for Wednesday through Friday) has been used to identify fingerprints of anthropogenic emissions. Based on daily maximum and minimum temperature series from the China Meteorological Administration homogenized dataset, the weekend effect in diurnal temperature range (DTR) at 71 stations with elevations above 2000 m asl in the eastern and central Tibetan Plateau (TP) during 1961-2004 is examined, and principal component analysis (PCA) is performed to cluster series into four subregions with similar weekend effect variability. The DTR demonstrates a much stronger negative weekend effect in autumn and shows larger positive values in winter, which provides a strong evidence of anthropogenic activity in this region, especially in the central TP. Analysis by topographic type and degree of urbanization shows a clear weekly cycle which cannot be explained by a microclimate effect. We hypothesize that the interaction with anthropogenic aerosols from local emissions and transported by atmospheric circulation may account for the weekly cycle in the TP. More caution should be paid to the driving mechanism of the weekend effect in the most remote and clear regions in the world.

  2. Assessment of Operation of EMK21 MEMS Silicon Oscillator Over Wide Temperature Range

    Science.gov (United States)

    Patterson, Richard L.; Hammoud, Ahmad

    2009-01-01

    Electronic control systems, data-acquisition instrumentation, and microprocessors require accurate timing signals for proper operation. Traditionally, ceramic resonators and crystal oscillators provided this clock function for the majority of these systems. Over the last few years, MEMS (Micro-Electro-Mechanical Systems) resonator-based oscillators began to surface as commercial-off-the-shelf (COTS) parts by a few companies. These quartz-free, miniature silicon devices could easily replace the traditional crystal oscillators in providing the timing/clock function for many digital and analog circuits. They are reported to provide stable output frequency, offer great tolerance to shock and vibration, and are immune to electro-static discharge [ 1-2]. In addition, they are encapsulated in compact lead-free packages and cover a wide frequency range (1 MHz to 125 MHz). The small size of the MEMS oscillators along with their thermal stability make them ideal candidates for use in space exploration missions. Limited data, however, exist on the performance and reliability of these devices under operation in applications where extreme temperatures or thermal cycling swings, which are typical of space missions, are encountered. This report presents the results of the work obtained on the evaluation of an Ecliptek Corporation MEMS silicon oscillator chip under extreme temperatures.

  3. Reliability and Analysis of Changes in Bite Marks at Different Time Intervals and Temperature Ranges

    Directory of Open Access Journals (Sweden)

    Parul Khare Sinha

    2017-04-01

    Full Text Available Objectives: The purpose of this study is to assess time-dependent changes in the morphology of bitemarks and to investigate the utility of matching bitemarks on both perishable and non-perishable objects with the passage of time at different temperatures. Subjects and Methods: The study was conducted at Maharana Pratap College of Dentistry and Research Centre, Gwalior, India. 20 volunteers were asked to bite 6 items each. These included perishable and nonperishable items. Perishable items were apple, banana and Burfi, (a milk-based popular sweet confectionary while non-perishable items included wax, clay, and rubber. Photographs were taken with a digital camera at 0-hours and 24-hours after biting these objects at temperature ranges of 24 ºC to 28 ºC and 36 ºC to 40 ºC, respectively. Life-size photographs of these bitten objects were printed on transparent overlays and compared to hand drawn transparencies prepared from suspect dentition using an X-ray viewer. The comparison of all the 960 transparencies was done by two researchers, independently. Results: All objects gave a positive identification of the biter on matching just after biting. After24-hours, all items also showed positive matching except banana and apples. Conclusion: This proposed method is simple, reliable and less technique sensitive. It narrows down the subjectivity of interpretation. It highlights that due to decomposition changes occur in perishable food items and more so in apples and bananas, making bitemarks less reliable evidence.

  4. Comparison of physically based constitutive models characterizing armor steel over wide temperature and strain rate ranges

    International Nuclear Information System (INIS)

    Xu, Zejian; Huang, Fenglei

    2012-01-01

    Both descriptive and predictive capabilities of five physically based constitutive models (PB, NNL, ZA, VA, and RK) are investigated and compared systematically, in characterizing plastic behavior of the 603 steel at temperatures ranging from 288 to 873 K, and strain rates ranging from 0.001 to 4500 s −1 . Determination of the constitutive parameters is introduced in detail for each model. Validities of the established models are checked by strain rate jump tests performed under different loading conditions. The results show that the RK and NNL models have better performance in the description of material behavior, especially the work-hardening effect, while the PB and VA models predict better. The inconsistency that is observed between the capabilities of description and prediction of the models indicates the existence of the minimum number of required fitting data, reflecting the degree of a model's requirement for basic data in parameter calibration. It is also found that the description capability of a model is dependent to a large extent on both its form and the number of its constitutive parameters, while the precision of prediction relies largely on the performance of description. In the selection of constitutive models, the experimental data and the constitutive models should be considered synthetically to obtain a better efficiency in material behavior characterization

  5. Comparison of physically based constitutive models characterizing armor steel over wide temperature and strain rate ranges

    Science.gov (United States)

    Xu, Zejian; Huang, Fenglei

    2012-01-01

    Both descriptive and predictive capabilities of five physically based constitutive models (PB, NNL, ZA, VA, and RK) are investigated and compared systematically, in characterizing plastic behavior of the 603 steel at temperatures ranging from 288 to 873 K, and strain rates ranging from 0.001 to 4500 s-1. Determination of the constitutive parameters is introduced in detail for each model. Validities of the established models are checked by strain rate jump tests performed under different loading conditions. The results show that the RK and NNL models have better performance in the description of material behavior, especially the work-hardening effect, while the PB and VA models predict better. The inconsistency that is observed between the capabilities of description and prediction of the models indicates the existence of the minimum number of required fitting data, reflecting the degree of a model's requirement for basic data in parameter calibration. It is also found that the description capability of a model is dependent to a large extent on both its form and the number of its constitutive parameters, while the precision of prediction relies largely on the performance of description. In the selection of constitutive models, the experimental data and the constitutive models should be considered synthetically to obtain a better efficiency in material behavior characterization.

  6. The Effect of a Pre-Lens Aperture on the Temperature Range and Image Uniformity of Microbolometer Infrared Cameras

    Energy Technology Data Exchange (ETDEWEB)

    Dinwiddie, Ralph Barton [ORNL; Parris, Larkin S. [Wichita State University; Lindal, John M. [Oak Ridge National Laboratory (ORNL); Kunc, Vlastimil [ORNL

    2016-01-01

    This paper explores the temperature range extension of long-wavelength infrared (LWIR) cameras by placing an aperture in front of the lens. An aperture smaller than the lens will reduce the radiance to the sensor, allowing the camera to image targets much hotter than typically allowable. These higher temperatures were accurately determined after developing a correction factor which was applied to the built-in temperature calibration. The relationship between aperture diameter and temperature range is linear. The effect of pre-lens apertures on the image uniformity is a form of anti-vignetting, meaning the corners appear brighter (hotter) than the rest of the image. An example of using this technique to measure temperatures of high melting point polymers during 3D printing provide valuable information of the time required for the weld-line temperature to fall below the glass transition temperature.

  7. Lagged effect of diurnal temperature range on mortality in a subtropical megacity of China.

    Directory of Open Access Journals (Sweden)

    Yuan Luo

    Full Text Available BACKGROUND: Many studies have found extreme temperature can increase the risk of mortality. However, it is not clear whether extreme diurnal temperature range (DTR is associated with daily disease-specific mortality, and how season might modify any association. OBJECTIVES: To better understand the acute effect of DTR on mortality and identify whether season is a modifier of the DTR effect. METHODS: The distributed lag nonlinear model (DLNM was applied to assess the non-linear and delayed effects of DTR on deaths (non-accidental mortality (NAD, cardiovascular disease (CVD, respiratory disease (RD and cerebrovascular disease (CBD in the full year, the cold season and the warm season. RESULTS: A non-linear relationship was consistently found between extreme DTR and mortality. Immediate effects of extreme low DTR on all types of mortality were stronger than those of extreme high DTR in the full year. The cumulative effects of extreme DTRs increased with the increment of lag days for all types of mortality in cold season, and they were greater for extreme high DTRs than those of extreme low DTRs. In hot season, the cumulative effects for extreme low DTRs increased with the increment of lag days, but for extreme high DTR they reached maxima at a lag of 13 days for all types of mortality except for CBD(at lag6 days, and then decreased. CONCLUSIONS: Our findings suggest that extreme DTR is an independent risk factor of daily mortality, and season is a modifier of the association of DTR with daily mortality.

  8. Differential responses of invasive and native plants to warming with simulated changes in diurnal temperature ranges

    Science.gov (United States)

    Chen, Bao-Ming; Gao, Yang; Liao, Hui-Xuan

    2017-01-01

    Abstract Although many studies have documented the effects of global warming on invasive plants, little is known about whether the effects of warming on plant invasion differ depending on the imposed change in different diurnal temperature ranges (DTR). We tested the impact of warming with DTR change on seed germination and seedling growth of eight species in the family Asteraceae. Four of these are invasive (Eupatorium catarium, Mikania micrantha, Biodens pilosa var. radiate, Ageratum conyzoides) in China, and four are native (Sonchus arvensis, Senecios candens, Pterocypsela indica, Eupatorium fortunei). Four temperature treatments were set in growth chambers (three warming by 3 °C with different DTRs and control), and experiments were run to mimic wintertime and summertime conditions. The control treatment (Tc) was set to the mean temperature for the corresponding time of year, and the three warming treatments were symmetric (i.e. equal night-and-day) (DTRsym), asymmetric warming with increased (DTRinc) and decreased (DTRdec) DTR. The warming treatments did not affect seed germination of invasive species under any of the conditions, but DTRsym and DTRinc increased seed germination of natives relative to the control, suggesting that warming may not increase success of these invasive plant species via effects on seed germination of invasive plants relative to native plants. The invasive plants had higher biomass and greater stem allocation than the native ones under all of the warming treatments. Wintertime warming increased the biomass of the invasive and wintertime DTRsym and DTRinc increased that of the native plants, whereas summertime asymmetric warming decreased the biomass of the invasives but not the natives. Therefore, warming may not facilitate invasion of these invasive species due to the suppressive effects of summertime warming (particularly the asymmetric warming) on growth. Compared with DTRsym, DTRdec decreased the biomass of both the invasive

  9. Extended-range forecasting of Chinese summer surface air temperature and heat waves

    Science.gov (United States)

    Zhu, Zhiwei; Li, Tim

    2018-03-01

    Because of growing demand from agricultural planning, power management and activity scheduling, extended-range (5-30-day lead) forecasting of summer surface air temperature (SAT) and heat waves over China is carried out in the present study via spatial-temporal projection models (STPMs). Based on the training data during 1960-1999, the predictability sources are found to propagate from Europe, Northeast Asia, and the tropical Pacific, to influence the intraseasonal 10-80 day SAT over China. STPMs are therefore constructed using the projection domains, which are determined by these previous predictability sources. For the independent forecast period (2000-2013), the STPMs can reproduce EOF-filtered 30-80 day SAT at all lead times of 5-30 days over most part of China, and observed 30-80 and 10-80 day SAT at 25-30 days over eastern China. Significant pattern correlation coefficients account for more than 50% of total forecasts at all 5-30-day lead times against EOF-filtered and observed 30-80 day SAT, and at a 20-day lead time against observed 10-80 day SAT. The STPMs perform poorly in reproducing 10-30 day SAT. Forecasting for the first two modes of 10-30 day SAT only shows useful skill within a 15-day lead time. Forecasting for the third mode of 10-30 day SAT is useless after a 10-day lead time. The forecasted heat waves over China are determined by the reconstructed SAT which is the summation of the forecasted 10-80 day SAT and the lower frequency (longer than 80-day) climatological SAT. Over a large part of China, the STPMs can forecast more than 30% of heat waves within a 15-day lead time. In general, the STPMs demonstrate the promising skill for extended-range forecasting of Chinese summer SAT and heat waves.

  10. Improved Models and Tools for Prediction of Radiation Effects on Space Electronics in Wide Temperature Range, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — All NASA exploration systems operate in the extreme environments of space and require reliable electronics capable of handling a wide temperature range (-180ºC to...

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

    Science.gov (United States)

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

    2015-06-01

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

  12. Diurnal Temperature Range in Relation to Daily Mortality and Years of Life Lost in Wuhan, China.

    Science.gov (United States)

    Zhang, Yunquan; Yu, Chuanhua; Yang, Jin; Zhang, Lan; Cui, Fangfang

    2017-08-08

    Diurnal temperature range (DTR) is an important meteorological indicator associated with global climate change, and has been linked with mortality and morbidity in previous studies. To date, however, little evidence has been available regarding the association of DTR with years of life lost (YLL). This study aimed to evaluate the DTR-related burden on both YLL and mortality. We collected individual records of all registered deaths and daily meteorological data in Wuhan, central China, between 2009 and 2012. For the whole population, every 1 °C increase in DTR at a lag of 0-1 days was associated with an increase of 0.65% (95% CI: 0.08-1.23) and 1.42 years (-0.88-3.72) for mortality and YLL due to non-accidental deaths, respectively. Relatively stronger DTR-mortality/YLL associations were found for cardiovascular deaths. Subgroup analyses (stratified by gender, age, and education level) showed that females, the elderly (75+ years old), and those with higher education attainment (7+ years) suffered more significantly from both increased YLL and mortality due to large DTR. Our study added additional evidence that short-term exposure to large DTR was associated with increased burden of premature death using both mortality incidence and YLL.

  13. Mortality burden of diurnal temperature range and its temporal changes: A multi-country study.

    Science.gov (United States)

    Lee, Whanhee; Bell, Michelle L; Gasparrini, Antonio; Armstrong, Ben G; Sera, Francesco; Hwang, Sunghee; Lavigne, Eric; Zanobetti, Antonella; Coelho, Micheline de Sousa Zanotti Stagliorio; Saldiva, Paulo Hilario Nascimento; Osorio, Samuel; Tobias, Aurelio; Zeka, Ariana; Goodman, Patrick G; Forsberg, Bertil; Rocklöv, Joacim; Hashizume, Masahiro; Honda, Yasushi; Guo, Yue-Liang Leon; Seposo, Xerxes; Van Dung, Do; Dang, Tran Ngoc; Tong, Shilu; Guo, Yuming; Kim, Ho

    2018-01-01

    Although diurnal temperature range (DTR) is a key index of climate change, few studies have reported the health burden of DTR and its temporal changes at a multi-country scale. Therefore, we assessed the attributable risk fraction of DTR on mortality and its temporal variations in a multi-country data set. We collected time-series data covering mortality and weather variables from 308 cities in 10 countries from 1972 to 2013. The temporal change in DTR-related mortality was estimated for each city with a time-varying distributed lag model. Estimates for each city were pooled using a multivariate meta-analysis. The results showed that the attributable fraction of total mortality to DTR was 2.5% (95% eCI: 2.3-2.7%) over the entire study period. In all countries, the attributable fraction increased from 2.4% (2.1-2.7%) to 2.7% (2.4-2.9%) between the first and last study years. This study found that DTR has significantly contributed to mortality in all the countries studied, and this attributable fraction has significantly increased over time in the USA, the UK, Spain, and South Korea. Therefore, because the health burden of DTR is not likely to reduce in the near future, countermeasures are needed to alleviate its impact on human health. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Effect of holding time in the ({alpha} + {gamma}) temperature range on toughness of specially austempered ductile iron

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, T.; Yamada, S. [Toyohashi Univ. of Technology (Japan). Dept. of Production Systems Engineering

    1996-07-01

    Austempered ductile iron (ADI) finds wide application in the industry because of its high strength and toughness. The QB{prime} process has been developed to produce a fine microstructure with high fracture toughness in ADI. This process involves reaustenitizing a prequenched ductile iron in the ({alpha} + {gamma}) temperature range followed by an isothermal treatment in the bainitic transformation temperature range. In the present work, the effect of holding time in the ({alpha} + {gamma}) temperature range on the structure and un-notched toughness of ADI has been studied. Prior to the austempering treatment, the as-cast ductile iron was heat treated to obtain martensitic, ferritic, and pearlitic matrix structures. In the case of prequenched material (martensitic matrix), the un-notched impact toughness increased as a function of holding time in the ({alpha} + {gamma}) temperature range. The reaustenitization heat treatment also resulted in the precipitation of fine carbide particles, identified as (Fe,Cr,Mn){sub 3}C. It was shown that the increase in holding time in the ({alpha} + {gamma}) temperature range leads to a reduction in the number of carbide particles. In the case of a ferritic prior structure, a long duration hold in the ({alpha} + {gamma}) temperature range resulted in the coarsening of the structure with a marginal increase in the toughness. In the case of a pearlitic prior structure, the toughness increased with holding time. This was attributed to the decomposition of the relatively stable carbide around the eutectic cell boundary with longer holding times.

  15. Temperature dependence of muonium spin exchange with O2 in the range 88 K to 478 K

    International Nuclear Information System (INIS)

    Senba, M.; Garner, D.M.; Arseneau, D.J.; Fleming, D.G.

    1984-01-01

    The authors have extended an earlier study of the spin exchange reactions of Mu with O 2 in the range 295 K to 478 K, to a low temperature region down to 88 K. From 135 K to 296 K, the spin depolarization rate constant was found to vary according to the relative velocity of the colliding species, which indicates that the spin exchange cross section of Mu-O 2 is temperature independent in this range. However, it was found that below 105 K and above 400 K, the spin depolarization rate constant tends to have stronger temperature dependences. (Auth.)

  16. Differential responses of invasive and native plants to warming with simulated changes in diurnal temperature ranges.

    Science.gov (United States)

    Chen, Bao-Ming; Gao, Yang; Liao, Hui-Xuan; Peng, Shao-Lin

    2017-07-01

    Although many studies have documented the effects of global warming on invasive plants, little is known about whether the effects of warming on plant invasion differ depending on the imposed change in different diurnal temperature ranges (DTR). We tested the impact of warming with DTR change on seed germination and seedling growth of eight species in the family Asteraceae. Four of these are invasive ( Eupatorium catarium , Mikania micrantha , Biodens pilosa var. radiate , Ageratum conyzoides ) in China, and four are native ( Sonchus arvensis , Senecios candens , Pterocypsela indica , Eupatorium fortunei ). Four temperature treatments were set in growth chambers (three warming by 3 °C with different DTRs and control), and experiments were run to mimic wintertime and summertime conditions. The control treatment ( T c ) was set to the mean temperature for the corresponding time of year, and the three warming treatments were symmetric (i.e. equal night-and-day) (DTR sym ), asymmetric warming with increased (DTR inc ) and decreased (DTR dec ) DTR. The warming treatments did not affect seed germination of invasive species under any of the conditions, but DTR sym and DTR inc increased seed germination of natives relative to the control, suggesting that warming may not increase success of these invasive plant species via effects on seed germination of invasive plants relative to native plants. The invasive plants had higher biomass and greater stem allocation than the native ones under all of the warming treatments. Wintertime warming increased the biomass of the invasive and wintertime DTR sym and DTR inc increased that of the native plants, whereas summertime asymmetric warming decreased the biomass of the invasives but not the natives. Therefore, warming may not facilitate invasion of these invasive species due to the suppressive effects of summertime warming (particularly the asymmetric warming) on growth. Compared with DTR sym , DTR dec decreased the biomass of

  17. Effects of diurnal temperature range on mortality in Hefei city, China

    Science.gov (United States)

    Tang, Jing; Xiao, Chang-chun; Li, Yu-rong; Zhang, Jun-qing; Zhai, Hao-yuan; Geng, Xi-ya; Ding, Rui; Zhai, Jin-xia

    2017-12-01

    Although several studies indicated an association between diurnal temperature range (DTR) and mortality, the results about modifiers are inconsistent, and few studies were conducted in developing inland country. This study aims to evaluate the effects of DTR on cause-specific mortality and whether season, gender, or age might modify any association in Hefei city, China, during 2007-2016. Quasi-Poisson generalized linear regression models combined with a distributed lag non-linear model (DLNM) were applied to evaluate the relationships between DTR and non-accidental, cardiovascular, and respiratory mortality. We observed a J-shaped relationship between DTR and cause-specific mortality. With a DTR of 8.3 °C as the reference, the cumulative effects of extremely high DTR were significantly higher for all types of mortality than effects of lower or moderate DTR in full year. When stratified by season, extremely high DTR in spring had a greater impact on all cause-specific mortality than other three seasons. Male and the elderly (≥ 65 years) were consistently more susceptible to extremely high DTR effect than female and the youth (< 65 years) for non-accidental and cardiovascular mortality. To the contrary, female and the youth were more susceptible to extremely high DTR effect than male and the elderly for respiratory morality. The study suggests that extremely high DTR is a potential trigger for non-accidental mortality in Hefei city, China. Our findings also highlight the importance of protecting susceptible groups from extremely high DTR especially in the spring.

  18. Biaxial creep deformation of Zircaloy-4 PWR fuel cladding in the alpha,(alpha + beta) and beta phase temperature ranges

    International Nuclear Information System (INIS)

    Donaldson, A.T.; Healey, T.; Horwood, R.A.L.

    1985-01-01

    The biaxial creep behaviour of Zircaloy-4 fuel cladding has been determined at temperatures between 973 - 1073 K in the alpha phase range, in the duplex (alpha + beta) region between 1098 - 1223 K and in the beta phase range between 1323 - 1473 K. This paper presents the creep data together with empirical equations which describe the creep deformation response within each phase region. (author)

  19. Comparison of the radiation temperature scales of the PTB and the NPL in the temperature range from −57 °C to 50 °C

    International Nuclear Information System (INIS)

    Gutschwager, B; Monte, C; Adibekyan, A; Reiniger, M; Hollandt, J; Theocharous, E; Fox, N P

    2013-01-01

    Blackbody sources at near-ambient temperature are routinely used to calibrate infrared instruments used in remote sensing and thermal imaging applications to measure radiance and radiation temperature. The measured temperature of the blackbody and its calculated effective emissivity determine its radiance and radiation temperature according to Planck's law. The temperature measurement is generally accomplished with a contact thermometer which is calibrated against the International Temperature Scale (ITS-90). The ammonia heat-pipe blackbody of the Physikalisch-Technische Bundesanstalt (PTB) in Germany is a primary source standard working over a wide spectral range with low uncertainties, i.e. less than 33 mK at 10 µm in the temperature range from –60 °C to 50 °C. A more direct method of absolute radiance measurement is to use an absolutely calibrated radiometer, calibrated against a primary detector standard, the cryogenic radiometer. AMBER (Absolute Measurements of Blackbody Emitted Radiance) is an absolutely calibrated radiometer of the Optical Measurement Group of the National Physical Laboratory (NPL) in the UK which was specially designed to determine the radiance and hence the radiation temperature of near-ambient-temperature blackbodies. When AMBER is operated at short wavelengths, where photodetectors offering good long-term stability exist, it derives its traceability through the cryogenic radiometer. However, available photodetectors operating in the 8 µm to 12 µm wavelength range offer poor long-term stability so when AMBER is used in this wavelength range, the NPL radiance temperature scale is based on a gallium fixed-point blackbody operating at 29.7646 °C (ITS-90). At other radiance temperatures, the NPL scale also relies on the gallium fixed-point blackbody but requires the calibration of the relative spectral irradiance responsivity of the AMBER radiometer (done against NPL spectral responsivity standards), measurement of the radiometric

  20. Kinetic Testing of Nitrate-Based Sodalite Formation Over the Temperature Range of 40 to 100 Degrees Centigrade (Final Report)

    Energy Technology Data Exchange (ETDEWEB)

    Mattus, A.J.

    2001-09-07

    The focus of this study was the desilication kinetics of a Savannah River Site (SRS) tank farm 2H simulant over the temperature range of 40 to 100 C. Results showed that the formation of nitrate-nitrite-based sodalite over aluminum-to-silicon (Al:Si) molar ratios ranging from 1:1 to 20:1 exhibited overall-second order kinetics. The Arrhenius apparent activation energy associated with the crystal growth process of the sodalite was determined to be 35 kJ/mol over the temperature range investigated. Second-order rate constants were extrapolated to the 2H evaporator working temperature of {approx} 130 C and were found to be 0.012 L mol{sup -1} s{sup -1}. At this operating temperature, the half-life of a limiting reactant with a 0.1 M feed would be 14 min.

  1. Wide Temperature Range Kinetics of Elementary Combustion Reactions for Army Models

    National Research Council Canada - National Science Library

    Fontijn, Arthur

    2002-01-01

    The goals of this program are to provide accurate kinetic data on isolated elementary reactions at temperatures relevant to Army combustion models, particularly for propellant combustion dark zones...

  2. Passive Wireless Temperature Sensors with Enhanced Sensitivity and Range, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal describes the development of a wireless multisensor system for NASA application to remote wireless sensing of temperature distributions in composite...

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

    Science.gov (United States)

    Wilson, Robert M.

    2013-01-01

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

  4. Dust Radiative Forcing Impacts on Diurnal Temperature Range: Indirect Impacts of Land Cover and Land Use Change in Sahel

    Science.gov (United States)

    Phillips, C. E.; Nair, U.; Xian, P.

    2017-12-01

    Surface temperature observations in the Sahel region show trends of maximum (Tmax), minimum (Tmin) temperatures and the diurnal temperature range (DTR) that have been attributed to climate variability and land use and land cover change (LULC). However, the contributions of dust radiative forcing to surface temperature trends are not well understood. These contributions could also vary depending upon climate and LULC changes. We utilized a one-dimensional numerical model that incorporates radiative forcing from mineral dust and biomass burning aerosols to develop a conceptual framework for analyzing the radiative forcing impact on surface temperatures in Sahel. For the observed ranges of dust and aerosol loading, shortwave and longwave radiative forcing at the surface are -84.7 Wm-2 and 11.2 Wm-2 respectively, leading to a decrease in the DTR of between 0.81 K and 1.11 K. Aerosol radiative forcing in this region also leads to consistent increase in nocturnal minimum temperature. Interannual variability of dust radiative forcing can account for up to 2.6 degrees in DTR and 2.4 degrees in nocturnal minimum temperature. Our analysis also shows that changes in dust loading resulting from LULC change can lead to significant changes in the DTR and nocturnal minimum temperature and thus should be considered in the analysis of temperature trends in regions such as Sahel.

  5. Temperature dependence of the electrical resistivity of R6(Fesub(1-x)Mnsub(x))23 compounds in the temperature range 4.2 to 300 K

    International Nuclear Information System (INIS)

    Gratz, E.; Kirchmayr, H.R.

    1976-01-01

    The temperature dependence of the electrical resistivity rho of binary R 6 Mn 23 , R 6 Fe 23 (R=Y,Dy,Ho,Er,Tm) and pseudobinary R 6 (Fesub(1-x)Mnsub(x)) 23 (R=Y,Er,Ho) compounds has been determined by a four-probe measuring technique in the temperature range 4 to 300 K. The binary compounds exhibit a rho prop. T 2 dependence at low temperatures, while above 100 K a negative curvature of the rho-T-curves is observed. These experimental results are discussed on the basis of electron-spin wave scattering in the low temperature range and on the basis of s-d scattering in the high temperature range, taking explicitly into account the temperature dependence of the chemical potentials. The pseudobinary compounds generally exhibit a decreasing resistivity with increasing temperature, combined with a high residual resistivity. These facts are explained by the so-called strong scattering mechanism and the appearance of 'quasilocalized' states. (Auth.)

  6. Normal range and lateral symmetry in the skin temperature profile of pregnant women

    Science.gov (United States)

    Pereira, Tânia; Nogueira-Silva, Cristina; Simoes, Ricardo

    2016-09-01

    Body skin temperature is a useful parameter for diagnosing diseases and infrared thermography can be a powerful tool in providing important information to detect body temperature changes in a noninvasive way. The aim of this work was to study the pattern of skin temperature during pregnancy, to establish skin temperature reference values and to find correlations between these and the pregnant population characteristics. Sixty-one healthy pregnant women (mean age 30.6 ± 5.1 years) in the 8th-40th gestational week with normal pregnancies were examined in 31 regions of interest (ROI). The ROIs were defined all over the body in order to determine the most influenced by factors such as age or body mass index (BMI). The results obtained in this work highlight that in normal pregnant women the skin temperature is symmetrically distributed, with the symmetrical areas differing less than 0.5 °C , with a mean value of 0.25 ± 0.23 °C . This study identified a significant negative correlation between the BMI and temperature. Age has been shown to have great influence on the skin temperature, with a significant increase of temperature observed with age. This work explores a novel medical application of infrared thermography and provides a characterization of thermal skin profile in human pregnancy for a large set of ROIs while also evaluating the effects of age and BMI.

  7. Plant-soil feedback of native and range-expanding plant species is insensitive to temperature

    NARCIS (Netherlands)

    Van Grunsven, R.H.A.; Van der Putten, W.H.; Bezemer, T.M.; Veenendaal, E.M.

    2010-01-01

    Temperature change affects many aboveground and belowground ecosystem processes. Here we investigate the effect of a 5°C temperature increase on plant–soil feedback. We compare plant species from a temperate climate region with immigrant plants that originate from warmer regions and have recently

  8. Plant-soil feedback of native and range expanding plant species is insensitive to temperature

    NARCIS (Netherlands)

    Grunsven, van R.H.A.; Veenendaal, E.M.; Bezemer, T.M.; Putten, van der W.H.

    2010-01-01

    Temperature change affects many aboveground and belowground ecosystem processes. Here we investigate the effect of a 5°C temperature increase on plant–soil feedback. We compare plant species from a temperate climate region with immigrant plants that originate from warmer regions and have recently

  9. Sodium fire test at broad ranges of temperature and oxygen concentrations (4). Low temperature sodium spray tests (Translated document)

    International Nuclear Information System (INIS)

    Ohno, Shuji

    2012-02-01

    Sodium spray fire tests at an initial sodium temperature of 250degC were conducted under the atmospheric conditions of air (21% oxygen) and nitrogen with 3% oxygen to determine both the sodium burning rate and the aerosol release fraction, and compare them with the test results at the initial sodium temperature of 500degC in air atmosphere. In the tests, sodium was supplied using a spray nozzle into a stainless steel vessel of 100 m 3 (SOLFA-2). The sodium burning rate was calculated from two independent methods: the consumption rate of oxygen in the vessel, and the enthalpy change in the vessel constituents during the test. The aerosol release fraction during the test was evaluated by the comparison between the measured aerosol concentrations and the calculations with the ABC-INTG code. The main conclusions were as follows, (1) In air atmosphere, a) sodium droplets ignited instantaneously and the spray fire was observed even under low initial sodium temperature of 250degC, and b) the sodium burning rate was about 400 g-Na/s and its fraction of supplied sodium flow rate was about 70%. (2) In nitrogen atmosphere with 3% oxygen, a) ignition of sodium droplets was not observed under the 250degC condition, and b) the sodium burning rate was about 44 g-Na/s and the fraction of supplied sodium flow rate was less than 10%. (author)

  10. Temperature dependence of the ozone obsorption spectrum over the wavelength range 410 to 760 nm

    Science.gov (United States)

    Burkholder, James B.; Talukdar, Ranajit K.

    1994-01-01

    The ozone, O3, absorption cross sections between 410 and 760 nm, the Chappuis band, were measured at 220, 240, 260, and 280 K relative to that at room temperature using a diode array spectrometer. The measured cross sections varied very slightly, less than 1%, with decreasing temperature between 550 and 660 nm, near the peak of the Chappuis band. At wavelengths away from the peak, the absorption cross sections decreased with decreasing temperature; e.g., about 40% at 420 nm between 298 and 220 K. These results are compared with previous measurements and the impact on atmospheric measurements are discussed.

  11. Intraspecific variation in thermal acclimation of photosynthesis across a range of temperatures in a perennial crop.

    Science.gov (United States)

    Zaka, Serge; Frak, Ela; Julier, Bernadette; Gastal, François; Louarn, Gaëtan

    2016-01-01

    Interest in the thermal acclimation of photosynthesis has been stimulated by the increasing relevance of climate change. However, little is known about intra-specific variations in thermal acclimation and its potential for breeding. In this article, we examined the difference in thermal acclimation between alfalfa (Medicago sativa) cultivars originating from contrasting origins, and sought to analyze the mechanisms in play. A series of experiments was carried out at seven growth temperatures between 5 and 35 °C using four cultivars from temperate and Mediterranean origin. Leaf traits, the photosynthetic rate at 25 °C (A400 (25)), the photosynthetic rate at optimal temperature (A400 (opt)), the thermal optimum of photosynthesis (Topt), and the photosynthetic parameters from the Farqhuar model were determined. Irrespective of cultivar origin, a clear shift in the temperature responses of photosynthesis was observed as a function of growth temperature, affecting thermal optimum of photosynthesis, photosynthetic rate at optimal temperature and photosynthetic rate at 25 °C. For both cultivars, Topt values increased linearly in leaves grown between 5 and 35 °C. Relative homeostasis of A400 (25) and A400 (opt) was found between 10 °C and 30 °C growth temperatures, but sharp declines were recorded at 5 and 35 °C. This homeostasis was achieved in part through modifications to leaf nitrogen content, which increased at extreme temperatures. Significant changes were also recorded regarding nitrogen partitioning in the photosynthetic apparatus and in the temperature dependence of photosynthetic parameters. The cultivars differed only in terms of the temperature response of photosynthetic parameters, with Mediterranean genotypes displaying a greater sensitivity of the maximum rate of Rubisco carboxylation to elevated temperatures. It was concluded that intra-specific variations in the temperature acclimation of photosynthesis exist among alfalfa cultivars

  12. Sodium fire test at broad ranges of temperature and oxygen concentration. 4. Low temperature sodium spray fire tests

    International Nuclear Information System (INIS)

    Kawata, Koji; Miyahara, Shinya

    2005-08-01

    Sodium spray fire tests at the initial sodium temperature of 250degC were conducted under the atmospheric conditions of air and 3% oxygen containing nitrogen to determine the sodium burning rate and the aerosol release fraction and compare them with the test results at the initial sodium temperature of 500degC in air atmosphere. In the tests, sodium was supplied using a commercial spray nozzle into a stainless steel vessel of 100 m 3 volume (SOLFA-2). The sodium burning rate was calculated from two independent methods: the consumption rate of oxygen in the vessel and the enthalpy change of vessel components during the test. The aerosol release fraction was determined from the comparison between the measured aerosol concentrations and the calculated ones by the ABC-INTG code. The main conclusions were as follows, (1) In air atmosphere, a) sodium droplets ignited instantaneously and the spray fire was observed, and b) the sodium burning rate was about 440 g-Na/s and the fraction of supplied sodium was about 70%. (2) In 3% oxygen containing nitrogen, a) ignition of sodium droplets was not observed, and b) the sodium burning rate was about 44 g-Na/s and the fraction of supplied sodium was less than 10%. (author)

  13. Elastic precursor wave decay in shock-compressed aluminum over a wide range of temperature

    Science.gov (United States)

    Austin, Ryan A.

    2018-01-01

    The effect of temperature on the dynamic flow behavior of aluminum is considered in the context of precursor wave decay measurements and simulations. In this regard, a dislocation-based model of high-rate metal plasticity is brought into agreement with previous measurements of evolving wave profiles at 300 to 933 K, wherein the amplification of the precursor structure with temperature arises naturally from the dislocation mechanics treatment. The model suggests that the kinetics of inelastic flow and stress relaxation are governed primarily by phonon scattering and radiative damping (sound wave emission from dislocation cores), both of which intensify with temperature. The manifestation of these drag effects is linked to low dislocation density ahead of the precursor wave and the high mobility of dislocations in the face-centered cubic lattice. Simulations performed using other typical models of shock wave plasticity do not reproduce the observed temperature-dependence of elastic/plastic wave structure.

  14. Radiation Hard Wide Temperature Range Mixed-Signal Components, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Low temperature survivability, high performance and radiation tolerance of electronics in combination is required for NASA's surface missions. Modern sub-micron CMOS...

  15. Thermal activation plasticity of nanocrystalline Ni-18.75 at.% Fe alloy in temperature range 4.2-350 K

    International Nuclear Information System (INIS)

    Tabachnikova, E.D.; Podol'skij, A.V.; Smirnov, S.N.; Psaruk, I.A.; Bengus, V.Z.; Li, H.; Li, L.; Chu, H.; Liao, P.K.

    2012-01-01

    The mechanical properties of nanocrystalline Ni-18.75 at.% Fe alloy (average grain size approx 22 nm) were studied in uniaxial compression in the temperature range 4.2-350 K. During deformation with a constant rate the temperature dependence of yield stress was registered and deformation curves were analyzed. Temperature dependences of the deforming stress, strain rate sensitivity of the deforming stress and activation volume of plastic deformation were measured for plastic strain of 2%. The thermal activation analysis of the experimental data was carried out. It was shown that the plastic deformation in the temperature range from 35 to 350 K was controlled by a single deformation mechanism. Empirical estimates of the parameters of interaction between dislocation and local barriers were obtained and internal stress values were evaluated.

  16. Temperature range and degree of acidity growth of isolate of indigenous bacteria on fermented feed “fermege”

    Science.gov (United States)

    Isnawati; Trimulyono, G.

    2018-01-01

    Fermege is a fermented feed of ruminants, especially goats made from water hyacinth (Eichhornia crassipes). Temperature range and pH need to know in making starter formula for acceleration of fermentation process at making ruminant feed made from this materials. The starter formula expired period can be extended by adjusting starter storage temperature and pH of the starter. This research was aimed to find the temperature and pH range for the growth of isolate of indigenous bacteria “fermege.” This research is an explorative research conducted by growing bacteria isolate indigenous fermege in liquid medium with various pH and incubation in various temperature. Bacterial population was calculated based on turbidity of bacterial suspension with turbidometer. The stages of this research were to isolate the bacteria present in the fermege, purify the isolates found, and then grow the isolates in a liquid medium with various pH values. The isolated bacterials were incubated at different temperature variations. The cell population density of the isolates was calculated after incubation for 24 hours. The results showed there were eight indigenous bacterial isolates. All isolates can grow in the pH range 6 and 7. Two isolates (Bacillus subtilis and B. pumilus) can grow at 4°C. All isolates obtained can grow at a temperature of 30°C. Isolates Bacillus badius, B. subtilis, B. cereus, Pseudomonas stutzeri and P. diminuta can grow at 50°C. Based on research indicates that indigenous fermege bacterial isolates have the ability to grow in the neutral pH range and temperature range between 4°C and 50°C.

  17. The impact of temperature on the bionomics of Aedes (Stegomyia) aegypti, with special reference to the cool geographic range margins.

    Science.gov (United States)

    Eisen, Lars; Monaghan, Andrew J; Lozano-Fuentes, Saul; Steinhoff, Daniel F; Hayden, Mary H; Bieringer, Paul E

    2014-05-01

    The mosquito Aedes (Stegomyia) aegypti (L.), which occurs widely in the subtropics and tropics, is the primary urban vector of dengue and yellow fever viruses, and an important vector of chikungunya virus. There is substantial interest in how climate change may impact the bionomics and pathogen transmission potential of this mosquito. This Forum article focuses specifically on the effects of temperature on the bionomics of Ae. aegypti, with special emphasis on the cool geographic range margins where future rising temperatures could facilitate population growth. Key aims are to: 1) broadly define intra-annual (seasonal) patterns of occurrence and abundance of Ae. aegypti, and their relation to climate conditions; 2) synthesize the existing quantitative knowledge of how temperature impacts the bionomics of different life stages of Ae. aegypti; 3) better define the temperature ranges for which existing population dynamics models for Ae. aegypti are likely to produce robust predictions; 4) explore potential impacts of climate warming on human risk for exposure to Ae. aegypti at its cool range margins; and 5) identify knowledge or data gaps that hinder our ability to predict risk of human exposure to Ae. aegypti at the cool margins of its geographic range now and in the future. We first outline basic scenarios for intra-annual occurrence and abundance patterns for Ae. aegypti, and then show that these scenarios segregate with regard to climate conditions in selected cities where they occur. We then review how near-constant and intentionally fluctuating temperatures impact development times and survival of eggs and immatures. A subset of data, generated in controlled experimental studies, from the published literature is used to plot development rates and survival of eggs, larvae, and pupae in relation to water temperature. The general shape of the relationship between water temperature and development rate is similar for eggs, larvae, and pupae. Once the lower

  18. HTP kinetics studies on isolated elementary combustion reactions over wide temperature ranges

    Energy Technology Data Exchange (ETDEWEB)

    Fontijn, A.; Adusei, G.Y.; Hranisavlevic, J.; Bajaj, P.N. [Rensselaer Polytechnic Institute, Troy, NY (United States)

    1993-12-01

    The goals of this project are to provide accurate data on the temperature dependence of the kinetics of elementary combustion reactions, (i) for use by combustion modelers, and (ii) to gain a better fundamental understanding of, and hence predictive ability for, the chemistry involved. Experimental measurements are made mainly by using the pseudo-static HTP (high-temperature photochemistry) technique. While continuing rate coefficient measurements, further aspects of kinetics research are being explored. Thus, starting from the data obtained, a method for predicting the temperature dependence of rate coefficients of oxygen-atom olefin experiment and confirms the underlying mechanistic assumptions. Mechanistic information of another sort, i.e. by product analysis, has recently become accessible with the inauguration of our heated flow tube mass spectrometer facility; early results are reported here. HTP experiments designed to lead to measurements of product channels by resonance fluorescence have started.

  19. Interaction of austenitic stainless steels with steam in temperature range 350...1200 C

    International Nuclear Information System (INIS)

    Ishchenko, N.I.; Petel'guzov, I.A.; Slabospitskaya, E.A.

    2016-01-01

    Interaction of steels 08Cr18Ni10Ti and 0Cr16Ni15Mo3Nb (EI-847) with steam at elevated temperatures from 450 to 1200 C and for comparison water corrosion at 350 C were investigated. Corrosion kinetics and oxide layer structure were studied, thicknesses of oxide layers and of unoxidized metal were measured, mechanical properties of steels after corrosion tests were determined. After tests at temperatures up to 700...800 C the exfoliating of the top oxide layers and irregular mass gain kinetics were observed, despite oxide layers grew and were preserved on samples. The possible composition of oxide layers was analyzed. The oxidized samples of steels after high-temperature tests still had strength and plasticity. The results can be of interest when examining the possibility of using steels as fuel cladding

  20. Broad-temperature range spectroscopy of the two-centre modular redox metalloprotein Desulfovibrio desulfuricans desulfoferrodoxin

    DEFF Research Database (Denmark)

    Andersen, Niels Højmark; Harnung, S.E.; Trabjerg, I.

    2003-01-01

    /VIS, MCD, CD, and EPR spectroscopy. The UV/VIS spectra of grey DFx at room temperature is characterised by broad charge transfer (CT) transitions associated with oxidised centre 1 (495 and 368 nm) and II (335 and 635 nm). The transitions are resolved at 78 K, substantiated by VT-MCD and -CD. The data offer......The electronic-vibrational couplings of the two-centre non-heme iron protein Desulfovibrio desulfuricans desulfoferrodoxin (DFx) in three oxidation states, i.e. fully oxidised (grey), half-oxidised (pink), and fully reduced (colourless), have been investigated by variable temperature (VT) UV...

  1. Optical properties of bismuth-doped silica fibres in the temperature range 300 — 1500 K

    International Nuclear Information System (INIS)

    Dvoretskii, D A; Bufetov, Igor' A; Vel'miskin, V V; Zlenko, Alexander S; Khopin, V F; Semjonov, S L; Guryanov, Aleksei N; Denisov, L K; Dianov, Evgenii M

    2012-01-01

    The visible and near-IR absorption and luminescence bands of bismuth-doped silica and germanosilicate fibres have been measured for the first time as a function of temperature. The temperature-dependent IR luminescence lifetime of a bismuth-related active centre associated with silicon in the germanosilicate fibre has been determined. The Bi 3+ profile across the silica fibre preform is shown to differ markedly from the distribution of IR-emitting bismuth centres associated with silicon. The present results strongly suggest that the IR-emitting bismuth centre comprises a lowvalence bismuth ion and an oxygen-deficient glass network defect. (optical fibres, lasers and amplifiers. properties and applications)

  2. All-solid-state lithium-oxygen battery with high safety in wide ambient temperature range

    OpenAIRE

    Hirokazu Kitaura; Haoshen Zhou

    2015-01-01

    There is need to develop high energy storage devices with high safety to satisfy the growing industrial demands. Here, we show the potential to realize such batteries by assembling a lithium-oxygen cell using an inorganic solid electrolyte without any flammable liquid or polymer materials. The lithium-oxygen battery using Li1.575Al0.5Ge1.5(PO4)3 solid electrolyte was examined in the pure oxygen atmosphere from room temperature to 120??C. The cell works at room temperature and first full disch...

  3. Defining the response of a microorganism to temperatures that span its complete growth temperature range (-2°C to 28°C) using multiplex quantitative proteomics.

    Science.gov (United States)

    Williams, Timothy J; Lauro, Federico M; Ertan, Haluk; Burg, Dominic W; Poljak, Anne; Raftery, Mark J; Cavicchioli, Ricardo

    2011-08-01

    The growth of all microorganisms is limited to a specific temperature range. However, it has not previously been determined to what extent global protein profiles change in response to temperatures that incrementally span the complete growth temperature range of a microorganism. As a result it has remained unclear to what extent cellular processes (inferred from protein abundance profiles) are affected by growth temperature and which, in particular, constrain growth at upper and lower temperature limits. To evaluate this, 8-plex iTRAQ proteomics was performed on the Antarctic microorganism, Methanococcoides burtonii. Methanococcoides burtonii was chosen due to its importance as a model psychrophilic (cold-adapted) member of the Archaea, and the fact that proteomic methods, including subcellular fractionation procedures, have been well developed. Differential abundance patterns were obtained for cells grown at seven different growth temperatures (-2°C, 1°C, 4°C, 10°C, 16°C, 23°C, 28°C) and a principal component analysis (PCA) was performed to identify trends in protein abundances. The multiplex analysis enabled three largely distinct physiological states to be described: cold stress (-2°C), cold adaptation (1°C, 4°C, 10°C and 16°C), and heat stress (23°C and 28°C). A particular feature of the thermal extremes was the synthesis of heat- and cold-specific stress proteins, reflecting the important, yet distinct ways in which temperature-induced stress manifests in the cell. This is the first quantitative proteomic investigation to simultaneously assess the response of a microorganism to numerous growth temperatures, including the upper and lower growth temperatures limits, and has revealed a new level of understanding about cellular adaptive responses. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  4. Bayesian prediction of bacterial growth temperature range based on genome sequences

    DEFF Research Database (Denmark)

    Jensen, Dan Børge; Vesth, Tammi Camilla; Hallin, Peter Fischer

    2012-01-01

    Background: The preferred habitat of a given bacterium can provide a hint of which types of enzymes of potential industrial interest it might produce. These might include enzymes that are stable and active at very high or very low temperatures. Being able to accurately predict this based on a gen...... and psychrophilic adapted bacterial genomes....

  5. TEMPERATURE TOLERANCE AND LATITUDINAL RANGE OF BROWN-ALGAE FROM TEMPERATE PACIFIC SOUTH-AMERICA

    NARCIS (Netherlands)

    PETERS, AF; BREEMAN, AM

    Lower and upper survival temperatures of microthalli of 25 species of South American Phaeophyceae isolated from central Peru (14-degrees-S) to the Canal Beagle (55-degrees-S) were determined using 2-wk exposure for the upper and 4-wk exposure for the lower limit. All species survive 4 wks at -

  6. Forgings made of austenitic chromium-nickel steels for the low temperature range

    International Nuclear Information System (INIS)

    Gruendler, O.; Schwarz, W.; Koren, M.

    1981-01-01

    The authors discuss the low temperature application of austenitic chromium-nickel steels for energy production and process techniques. Material requirements are presented, and the behaviour, mechanical and physical properties of such steels are discussed. The manufacture of forgings is considered and test results presented. (Auth.)

  7. Forgings made of austenitic chromium-nickel steels for the low temperature range

    Energy Technology Data Exchange (ETDEWEB)

    Gruendler, O.; Schwarz, W.; Koren, M. (Vereinigte Edelstahlwerke A.G. (VEW), Kapfenberg (Austria))

    1981-09-01

    The authors discuss the low temperature application of austenitic chromium-nickel steels for energy production and process techniques. Material requirements are presented, and the behaviour, mechanical and physical properties of such steels are discussed. The manufacture of forgings is considered and test results presented.

  8. Intelligent Data Transfer for Multiple Sensor Networks over a Broad Temperature Range

    Science.gov (United States)

    Krasowski, Michael (Inventor)

    2018-01-01

    A sensor network may be configured to operate in extreme temperature environments. A sensor may be configured to generate a frequency carrier, and transmit the frequency carrier to a node. The node may be configured to amplitude modulate the frequency carrier, and transmit the amplitude modulated frequency carrier to a receiver.

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

    Science.gov (United States)

    2013-03-01

    from the southeast area and Pusan (the second largest city in South Korea). The volcanic island of Cheju-do is located in the southern portion of this...highest correlation magnitude is to the northeast of Madagascar in the Indian Ocean. 35 Correlation of sea surface temperatures (SSTs) for Dec

  10. Germination of Winter Annual Grass Weeds under a Range of Temperatures and Water Potentials

    DEFF Research Database (Denmark)

    Scherner, Ananda; Melander, Bo; Jensen, Peter Kryger

    2017-01-01

    Silky windgrass and annual bluegrass are among the most troublesome weeds in northern European winter crops, while problems with rattail fescue have been especially linked to direct-drilling practices. This study investigated the germination patterns of silky windgrass, annual bluegrass, and ratt......Silky windgrass and annual bluegrass are among the most troublesome weeds in northern European winter crops, while problems with rattail fescue have been especially linked to direct-drilling practices. This study investigated the germination patterns of silky windgrass, annual bluegrass......, and rattail fescue in multiple water potentials and temperature regimes. Temperature and water potential effects were similar between silky windgrass and rattail fescue, but differed from annual bluegrass. The three grass weeds were able to germinate under low water potential (−1.0 MPa), although water...... potentials ≤−0.25 MPa strongly delayed their germination. Silky windgrass and rattail fescue seeds were able to germinate at 1 C, while the minimum temperature for annual bluegrass germination was 5 C. Germination of silky windgrass and rattail fescue was very similar across temperature and water potentials...

  11. On the diurnal ranges of Sea Surface Temperature (SST) in the ...

    Indian Academy of Sciences (India)

    The variability of sea surface temperature (SST) is widely studied due to its large impact on ocean–atmosphere interaction. Kawai and Wada. (2007) provides an excellent review on the impor- tance of the diurnal variability of SST on air– sea interaction. Diurnal variations in the SST affect longer time-scale variability events ...

  12. All-solid-state lithium-oxygen battery with high safety in wide ambient temperature range.

    Science.gov (United States)

    Kitaura, Hirokazu; Zhou, Haoshen

    2015-08-21

    There is need to develop high energy storage devices with high safety to satisfy the growing industrial demands. Here, we show the potential to realize such batteries by assembling a lithium-oxygen cell using an inorganic solid electrolyte without any flammable liquid or polymer materials. The lithium-oxygen battery using Li1.575Al0.5Ge1.5(PO4)3 solid electrolyte was examined in the pure oxygen atmosphere from room temperature to 120 °C. The cell works at room temperature and first full discharge capacity of 1420 mAh g(-1) at 10 mA g(-1) (based on the mass of carbon material in the air electrode) was obtained. The charge curve started from 3.0 V, and that the majority of it lay below 4.2 V. The cell also safely works at high temperature over 80 °C with the improved battery performance. Furthermore, fundamental data of the electrochemical performance, such as cyclic voltammogram, cycle performance and rate performance was obtained and this work demonstrated the potential of the all-solid-state lithium-oxygen battery for wide temperature application as a first step.

  13. Range-wide latitudinal and elevational temperature gradients for the world's terrestrial birds: implications under global climate change.

    Science.gov (United States)

    La Sorte, Frank A; Butchart, Stuart H M; Jetz, Walter; Böhning-Gaese, Katrin

    2014-01-01

    Species' geographical distributions are tracking latitudinal and elevational surface temperature gradients under global climate change. To evaluate the opportunities to track these gradients across space, we provide a first baseline assessment of the steepness of these gradients for the world's terrestrial birds. Within the breeding ranges of 9,014 bird species, we characterized the spatial gradients in temperature along latitude and elevation for all and a subset of bird species, respectively. We summarized these temperature gradients globally for threatened and non-threatened species and determined how their steepness varied based on species' geography (range size, shape, and orientation) and projected changes in temperature under climate change. Elevational temperature gradients were steepest for species in Africa, western North and South America, and central Asia and shallowest in Australasia, insular IndoMalaya, and the Neotropical lowlands. Latitudinal temperature gradients were steepest for extratropical species, especially in the Northern Hemisphere. Threatened species had shallower elevational gradients whereas latitudinal gradients differed little between threatened and non-threatened species. The strength of elevational gradients was positively correlated with projected changes in temperature. For latitudinal gradients, this relationship only held for extratropical species. The strength of latitudinal gradients was better predicted by species' geography, but primarily for extratropical species. Our findings suggest threatened species are associated with shallower elevational temperature gradients, whereas steep latitudinal gradients are most prevalent outside the tropics where fewer bird species occur year-round. Future modeling and mitigation efforts would benefit from the development of finer grain distributional data to ascertain how these gradients are structured within species' ranges, how and why these gradients vary among species, and the capacity

  14. Range-wide latitudinal and elevational temperature gradients for the world's terrestrial birds: implications under global climate change.

    Directory of Open Access Journals (Sweden)

    Frank A La Sorte

    Full Text Available Species' geographical distributions are tracking latitudinal and elevational surface temperature gradients under global climate change. To evaluate the opportunities to track these gradients across space, we provide a first baseline assessment of the steepness of these gradients for the world's terrestrial birds. Within the breeding ranges of 9,014 bird species, we characterized the spatial gradients in temperature along latitude and elevation for all and a subset of bird species, respectively. We summarized these temperature gradients globally for threatened and non-threatened species and determined how their steepness varied based on species' geography (range size, shape, and orientation and projected changes in temperature under climate change. Elevational temperature gradients were steepest for species in Africa, western North and South America, and central Asia and shallowest in Australasia, insular IndoMalaya, and the Neotropical lowlands. Latitudinal temperature gradients were steepest for extratropical species, especially in the Northern Hemisphere. Threatened species had shallower elevational gradients whereas latitudinal gradients differed little between threatened and non-threatened species. The strength of elevational gradients was positively correlated with projected changes in temperature. For latitudinal gradients, this relationship only held for extratropical species. The strength of latitudinal gradients was better predicted by species' geography, but primarily for extratropical species. Our findings suggest threatened species are associated with shallower elevational temperature gradients, whereas steep latitudinal gradients are most prevalent outside the tropics where fewer bird species occur year-round. Future modeling and mitigation efforts would benefit from the development of finer grain distributional data to ascertain how these gradients are structured within species' ranges, how and why these gradients vary among

  15. Expanded Operational Temperature Range for Space Rated Li-Ion Batteries, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Quallion's Phase II proposal calls for expanding the nominal operation range of its space rated lithium ion cells, while maintaining their long life capabilities. To...

  16. Expanded Operational Temperature Range for Space Rated Li-Ion Batteries, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Quallion's response to this solicitation calls for expanding the nominal operation range of its space rated lithium ion cells, while maintaining their long life...

  17. The effect of temperature change on the load value of Japanese NiTi coil springs in the superelastic range.

    Science.gov (United States)

    Barwart, O

    1996-11-01

    Japanese nickel-titanium (NiTi) coil springs exhibit superelastic properties similar to the properties of Japanese NiTi wires. The springs exert a constant light, continuous force over a long range of increasing or decreasing activation. This property enables the springs to be used for physiologic orthodontic movement of teeth. A constant load value can be maintained only at constant temperatures. However, external influences affecting the mouth, for example when eating or drinking, cause fluctuations in temperature, which can be considerable. In this study, the effect of temperature change on the force delivery of NiTi springs in their superelastic range was investigated. Japanese NiTi closed coil springs were heated and cooled between 20 degrees C and 50 degrees C, while held in constant extension. During this procedure, the force was continually recorded. Commercially available stainless steel closed coil springs were tested in the same way. For all the springs examined, load values were found to increase with rising temperatures and to decrease with a drop in temperature. This relationship between temperature change and load was more pronounced in the case of NiTi than in the steel springs. The force measured at 37 degrees C was about twice as high as at 20 degrees C for one type of NiTi spring. On cooling, the superelastic springs showed unusual behavior. Immediately after the temperature started to drop, a rapid decrease in force occurred to levels below those found at rising temperatures. Such a nonlinear decrease in load was not observed in the stainless steel springs tested. The findings demonstrate that only minimal changes in temperature can cause significant changes in the force delivery of superelastic NiTi springs.

  18. Kinetics of the HO2 + BrO Reaction Over the Temperature Range 233-348 K

    Science.gov (United States)

    Li, Z.; Friedl, R. R.; Sander, S. P.

    1997-01-01

    The reaction BrO + HO2 products is the rate-limiting step in a key catalytic ozone destruction cycle in the lower stratosphere. In this study a discharge flow reactor coupled with molecular beam mass spectrometry has been used to study the BrO + HO2 reaction over the temperature range 233-348 K.

  19. Optical properties of bismuth-doped silica fibres in the temperature range 300 - 1500 K

    Energy Technology Data Exchange (ETDEWEB)

    Dvoretskii, D A; Bufetov, Igor' A; Vel' miskin, V V; Zlenko, Alexander S; Khopin, V F; Semjonov, S L; Guryanov, Aleksei N; Denisov, L K; Dianov, Evgenii M

    2012-09-30

    The visible and near-IR absorption and luminescence bands of bismuth-doped silica and germanosilicate fibres have been measured for the first time as a function of temperature. The temperature-dependent IR luminescence lifetime of a bismuth-related active centre associated with silicon in the germanosilicate fibre has been determined. The Bi{sup 3+} profile across the silica fibre preform is shown to differ markedly from the distribution of IR-emitting bismuth centres associated with silicon. The present results strongly suggest that the IR-emitting bismuth centre comprises a lowvalence bismuth ion and an oxygen-deficient glass network defect. (optical fibres, lasers and amplifiers. properties and applications)

  20. Response of a continuous anaerobic digester to temperature transitions: A critical range for restructuring the microbial community structure and function.

    Science.gov (United States)

    Kim, Jaai; Lee, Changsoo

    2016-02-01

    Temperature is a crucial factor that significantly influences the microbial activity and so the methanation performance of an anaerobic digestion (AD) process. Therefore, how to control the operating temperature for optimal activity of the microbes involved is a key to stable AD. This study examined the response of a continuous anaerobic reactor to a series of temperature shifts over a wide range of 35-65 °C using a dairy-processing byproduct as model wastewater. During the long-term experiment for approximately 16 months, the reactor was subjected to stepwise temperature increases by 5 °C at a fixed HRT of 15 days. The reactor showed stable performance within the temperature range of 35-45 °C, with the methane production rate and yield being maximum at 45 °C (18% and 26% greater, respectively, than at 35 °C). However, the subsequent increase to 50 °C induced a sudden performance deterioration with a complete cessation of methane recovery, indicating that the temperature range between 45 °C and 50 °C had a critical impact on the transition of the reactor's methanogenic activity from mesophilic to thermophilic. This serious process perturbation was associated with a severe restructuring of the reactor microbial community structure, particularly of methanogens, quantitatively as well as qualitatively. Once restored by interrupted feeding for about two months, the reactor maintained fairly stable performance under thermophilic conditions until it was upset again at 65 °C. Interestingly, in contrast to most previous reports, hydrogenotrophs largely dominated the methanogen community at mesophilic temperatures while acetotrophs emerged as a major group at thermophilic temperature. This implies that the primary methanogenesis route of the reactor shifted from hydrogen- to acetate-utilizing pathways with the temperature shifts from mesophilic to thermophilic temperatures. Our observations suggest that a mesophilic digester may not need to be cooled at up

  1. Thermal effects of an ICL-based mid-infrared CH4 sensor within a wide atmospheric temperature range

    Science.gov (United States)

    Ye, Weilin; Zheng, Chuantao; Sanchez, Nancy P.; Girija, Aswathy V.; He, Qixin; Zheng, Huadan; Griffin, Robert J.; Tittel, Frank K.

    2018-03-01

    The thermal effects of an interband cascade laser (ICL) based mid-infrared methane (CH4) sensor that uses long-path absorption spectroscopy were studied. The sensor performance in the laboratory at a constant temperature of ∼25 °C was measured for 5 h and its Allan deviation was ∼2 ppbv with a 1 s averaging time. A LabVIEW-based simulation program was developed to study thermal effects on infrared absorption and a temperature compensation technique was developed to minimize these effects. An environmental test chamber was employed to investigate the thermal effects that occur in the sensor system with variation of the test chamber temperature between 10 and 30 °C. The thermal response of the sensor in a laboratory setting was observed using a 2.1 ppm CH4 standard gas sample. Indoor/outdoor CH4 measurements were conducted to evaluate the sensor performance within a wide atmospheric temperature range.

  2. Creep and low cycles fatigue behaviour of inconel 617 and alloy 800H in the temperature range 1073-1223

    International Nuclear Information System (INIS)

    Yun, H.M.

    1984-01-01

    The creep rupture properties of high temperature alloys are being determined as part of the materials programme for the development of the high temperature, gas-cooled reactor (HTGR) as a source of nuclear process heat, especially for the gasification of lignite and coal. INCOLOY 800H AND INCONEL 617 have been tested in the temperature range from 1073 K to 1223 K in air as well as in helium with HTGR specific impurities. The static and dynamic creep behaviour of INCONEL 617 have been determined in constant load creep tests, relaxation tests and stress reduction tests. The results have been interpreted using the internal stress on the applied stress and test temperature was determined. In a few experiments the influence of cold deformation prior to the creep test on the magnitude of the internal stress was also investigated. (Author)

  3. On the diurnal ranges of Sea Surface Temperature (SST) in the ...

    Indian Academy of Sciences (India)

    A simple regression model based on the peak solar radiation and average wind speed was good enough to estimate the diurnal range of SST at ∼1.0 m in the north Indian Ocean during most of the seasons except under low wind-high solar radiation conditions that occur mostly during spring. The additional information on ...

  4. An evaluation of the transition temperature range of super-elastic orthodontic NiTi springs using differential scanning calorimetry.

    Science.gov (United States)

    Barwart, O; Rollinger, J M; Burger, A

    1999-10-01

    Differential scanning calorimetry (DSC) was used to determine the transition temperature ranges (TTR) of four types of super-elastic orthodontic nickel-titanium coil springs (Sentalloy). A knowledge of the TTR provides information on the temperature at which a NiTi wire or spring can assume superelastic properties and when this quality disappears. The spring types in this study can be distinguished from each other by their characteristic TTR during cooling and heating. For each tested spring type a characteristic TTR during heating (austenite transformation) and cooling (martensite transformation) was evaluated. The hysteresis of the transition temperature, found between cooling and heating, was 3.4-5.2 K. Depending on the spring type the austenite transformation started (As) at 9.7-17.1 degrees C and finished (Af) at 29.2-37 degrees C. The martensite transformation starting temperature (Ms) was evaluated at 32.6-25.4 degrees C, while Mf (martensite transformation finishing temperature) was 12.7-6.5 degrees C. The results show that the springs become super-elastic when the temperature increases and As is reached. They undergo a loss of super-elastic properties and a rapid decrease in force delivery when they are cooled to Mf. For the tested springs, Mf and As were found to be below room temperature. Thus, at room temperature and some degrees lower, all the tested springs exert super-elastic properties. For orthodontic treatment this means the maintenance of super-elastic behaviour, even when mouth temperature decreases to about room temperature as can occur, for example, during meals.

  5. Diffusion and agglomeration of helium in stainless steel in the temperature range from RT to 600 deg. C

    International Nuclear Information System (INIS)

    Zhang, C.H.; Chen, K.Q.; Zhu, Z.Y.

    2000-01-01

    Diffusion of helium and formation of helium bubbles in stainless steel in conditions of atomic displacement in the temperature range from RT to 600 deg. C are studied theoretically using standard rate equations. The dissociative mechanism via self-interstitial/He replacement is assumed to control helium diffusion and bubble formation. The numerical analysis shows that the temperature dependence of the effective diffusion coefficient of helium, the number density and the mean radius of bubbles has two distinctly different regimes with the transition occurring around 300 deg. C. The effective diffusion coefficient of helium, the number density and the mean radius of bubbles show weak temperature dependence in the low temperature regime, while they change abruptly with temperature in the high temperature regime. The results are qualitatively in agreement with the results of our experimental study on helium diffusion and bubble formation in helium-implanted 316L stainless steel. However, the discrepancy in the absolute values of number density and mean radius of bubbles between theoretical and experimental studies indicates that helium diffusion and bubble formation may be controlled by some athermal mechanisms in the low temperature regime

  6. Data Transfer for Multiple Sensor Networks Over a Broad Temperature Range

    Science.gov (United States)

    Krasowski, Michael

    2013-01-01

    At extreme temperatures, cryogenic and over 300 C, few electronic components are available to support intelligent data transfer over a common, linear combining medium. This innovation allows many sensors to operate on the same wire bus (or on the same airwaves or optical channel: any linearly combining medium), transmitting simultaneously, but individually recoverable at a node in a cooler part of the test area. This innovation has been demonstrated using room-temperature silicon microcircuits as proxy. The microcircuits have analog functionality comparable to componentry designed using silicon carbide. Given a common, linearly combining medium, multiple sending units may transmit information simultaneously. A listening node, using various techniques, can pick out the signal from a single sender, if it has unique qualities, e.g. a voice. The problem being solved is commonly referred to as the cocktail party problem. The human brain uses the cocktail party effect when it is able to recognize and follow a single conversation in a party full of talkers and other noise sources. High-temperature sensors have been used in silicon carbide electronic oscillator circuits. The frequency of the oscillator changes as a function of the changes in the sensed parameter, such as pressure. This change is analogous to changes in the pitch of a person s voice. The output of this oscillator and many others may be superimposed onto a single medium. This medium may be the power lines supplying current to the sensors, a third wire dedicated to data transmission, the airwaves through radio transmission, an optical medium, etc. However, with nothing to distinguish the identities of each source that is, the source separation this system is useless. Using digital electronic functions, unique codes or patterns are created and used to modulate the output of the sensor.

  7. On the diurnal ranges of sea surface temperature (SST) in the north Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Shenoi, S.S.C.; Nasnodkar, N.; Rajesh, G.; Joseph, K.J.; Suresh, I.; Almeida, A.M.

    satellite-based microwave and infrared sen- sors, indicated that a simple model of diurnal warming as a function of local time, wind speed and solar radiation can account for most of the diurnal warming (Gentemann et al 2003; Stuart–Menteth et al 2003... in 0.2 ◦ C bins according to their magni- tudes varying from −0.5 ◦ Cto2.1 ◦ C. The ΔSSTs that exceeded 2.1 ◦ Cweregroupedinthe>2.1 ◦ C bin. The bin width of 0.2 ◦ C was chosen consider- ing the measurement accuracy of temperature sen- sors attached...

  8. Temperature Dependence of Short-Range Order in β-Brass

    DEFF Research Database (Denmark)

    Dietrich, O.W.; Als-Nielsen, Jens Aage

    1967-01-01

    to the susceptibility chi, and that of the inverse correlation range k 1 were, respectively, fitted to the power laws chiprop((T-Tc)/T)-gamma and k 1 = (k/a)times((T-Tc)/Tc)nu, yielding gamma = 1.25plusmn0.02, nu = 0.65plusmn0.02, and k = 3.0plusmn0.3. Here a is the cube edge of the unit cell. These results agree...

  9. Tribological behavior and self-healing functionality of TiNbCN-Ag coatings in wide temperature range

    Science.gov (United States)

    Bondarev, A. V.; Kiryukhantsev-Korneev, Ph. V.; Levashov, E. A.; Shtansky, D. V.

    2017-02-01

    Ag- and Nb-doped TiCN coatings with about 2 at.% of Nb and Ag contents varied between 4.0 and 15.1 at.% were designed as promising materials for tribological applications in a wide temperature range. We report on the structure, mechanical, and tribological properties of TiNbCN-Ag coatings fabricated by simultaneous co-sputtering of TiC0.5 + 10%Nb2C and Ag targets in comparison with those of Ag-free coating. The tribological characteristics were evaluated during constant-temperature tests both at room temperature and 300 °C, as well as during dynamic temperature ramp tests in the range of 25-700 °C. The coating structure and elemental composition were studied by means of X-ray diffraction, scanning and transmission electron microscopy, and glow discharge optical emission spectroscopy. The coating microstructures and elemental compositions inside wear tracks, as well as the wear products, were examined by scanning electron microscopy, energy-dispersive spectroscopy, and Raman spectroscopy. We demonstrate that simultaneous alloying with Nb and Ag permits to overcome the main drawbacks of TiCN coatings such as their relatively high values of friction coefficient at elevated temperatures and low oxidation resistance. It is shown that a relatively high amount of Ag (15 at.%) is required to provide enhanced tribological behavior in a wide temperature range of 25-700 °C. In addition, the prepared Ag-doped coatings demonstrated active oxidation protection and self-healing functionality due to the segregation of Ag metallic particles in damage areas such as cracks, pin-holes, or oxidation sites.

  10. High energy storage density over a broad temperature range in sodium bismuth titanate-based lead-free ceramics.

    Science.gov (United States)

    Yang, Haibo; Yan, Fei; Lin, Ying; Wang, Tong; Wang, Fen

    2017-08-18

    A series of (1-x)Bi 0.48 La 0.02 Na 0.48 Li 0.02 Ti 0.98 Zr 0.02 O 3 -xNa 0.73 Bi 0.09 NbO 3 ((1-x)LLBNTZ-xNBN) (x = 0-0.14) ceramics were designed and fabricated using the conventional solid-state sintering method. The phase structure, microstructure, dielectric, ferroelectric and energy storage properties of the ceramics were systematically investigated. The results indicate that the addition of Na 0.73 Bi 0.09 NbO 3 (NBN) could decrease the remnant polarization (P r ) and improve the temperature stability of dielectric constant obviously. The working temperature range satisfying TCC 150  °C  ≤±15% of this work spans over 400 °C with the compositions of x ≥ 0.06. The maximum energy storage density can be obtained for the sample with x = 0.10 at room temperature, with an energy storage density of 2.04 J/cm 3 at 178 kV/cm. In addition, the (1-x)LLBNTZ-xNBN ceramics exhibit excellent energy storage properties over a wide temperature range from room temperature to 90 °C. The values of energy storage density and energy storage efficiency is 0.91 J/cm 3 and 79.51%, respectively, for the 0.90LLBNTZ-0.10NBN ceramic at the condition of 100 kV/cm and 90 °C. It can be concluded that the (1-x)LLBNTZ-xNBN ceramics are promising lead-free candidate materials for energy storage devices over a broad temperature range.

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

    Science.gov (United States)

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

    2017-04-01

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

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

    Science.gov (United States)

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

    2017-04-01

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

  13. Tribological behavior and self-healing functionality of TiNbCN-Ag coatings in wide temperature range

    Energy Technology Data Exchange (ETDEWEB)

    Bondarev, A.V., E-mail: abondarev88@gmail.com; Kiryukhantsev-Korneev, Ph.V.; Levashov, E.A.; Shtansky, D.V., E-mail: shtansky@shs.misis.ru

    2017-02-28

    Highlights: • TiNbCN–Ag coatings for wide temperature range tribological applications. • Alloying with Nb and Ag improve tribological properties and oxidation resistance. • Ag-rich TiNbCN coatings show friction coefficient below 0.45 in range of 25–700 °C. • Ag-doped coatings show active oxidation protection and self-healing functionality. - Abstract: Ag- and Nb-doped TiCN coatings with about 2 at.% of Nb and Ag contents varied between 4.0 and 15.1 at.% were designed as promising materials for tribological applications in a wide temperature range. We report on the structure, mechanical, and tribological properties of TiNbCN-Ag coatings fabricated by simultaneous co-sputtering of TiC{sub 0.5} + 10%Nb{sub 2}C and Ag targets in comparison with those of Ag-free coating. The tribological characteristics were evaluated during constant-temperature tests both at room temperature and 300 °C, as well as during dynamic temperature ramp tests in the range of 25–700 °C. The coating structure and elemental composition were studied by means of X-ray diffraction, scanning and transmission electron microscopy, and glow discharge optical emission spectroscopy. The coating microstructures and elemental compositions inside wear tracks, as well as the wear products, were examined by scanning electron microscopy, energy-dispersive spectroscopy, and Raman spectroscopy. We demonstrate that simultaneous alloying with Nb and Ag permits to overcome the main drawbacks of TiCN coatings such as their relatively high values of friction coefficient at elevated temperatures and low oxidation resistance. It is shown that a relatively high amount of Ag (15 at.%) is required to provide enhanced tribological behavior in a wide temperature range of 25–700 °C. In addition, the prepared Ag-doped coatings demonstrated active oxidation protection and self-healing functionality due to the segregation of Ag metallic particles in damage areas such as cracks, pin-holes, or oxidation sites.

  14. Preliminary Performance Evaluation of MEMS-based Piezoelectric Energy Harvesters in Extended Temperature Range

    DEFF Research Database (Denmark)

    Xu, R.; Borregaard, L.M.; Lei, A.

    2012-01-01

    In this work a batch of MEMS-based vibration energy harvesters consisting of a silicon/PZT thick film ntilever with integrated proof mass is characterized. The purpose of a vibration energy harvester is to convert low grade vibrations to useful electrical power. Optimally, the natural frequency...... of the harvester should match the frequency of he ambient vibration. The first step to achieve this is to evaluate the uniformity of the fabricated harvesters and nderstand the effects of temperature on the harvesters during operation. Therefore, the uniformity of 40 energy harvesters from one wafer has been...... evaluated. Thereafter the performance of the energy harvesters operating at emperatures between -30°C to 100°C was measured....

  15. Flexoelectric behavior in PIN-PMN-PT single crystals over a wide temperature range

    Science.gov (United States)

    Shu, Longlong; Li, Tao; Wang, Zhiguo; Li, Fei; Fei, Linfeng; Rao, Zhenggang; Ye, Mao; Ke, Shanming; Huang, Wenbin; Wang, Yu; Yao, Xi

    2017-10-01

    Flexoelectricity couples strain gradient to polarization and usually exhibits a large coefficient in the paraelectric phase of the ferroelectric perovskites. In this study, we employed the relaxor 0.3Pb(In1/2Nb1/2)O3-0.35Pb(Mg1/3Nb2/3)O3-0.35PbTiO3 (PIN-PMN-PT) single crystals to study the relationship between flexoelectric coefficients and the crystal structure. The flexoelectric coefficients in PIN-PMN-PT single crystal are found to vary from 57 μC/m at orthorhombic/monoclinic phase to 135 μC/m at tetragonal phase, and decreases to less than 27 μC/m in the temperature above Tm. This result discloses that ferroelectricity can significantly enhance the flexoelectricity in this kind of perovskite.

  16. Effect of a temperature increase in the non-noxious range on proton-evoked ASIC and TRPV1 activity.

    Science.gov (United States)

    Blanchard, Maxime G; Kellenberger, Stephan

    2011-01-01

    Acid-sensing ion channels (ASICs) are neuronal H(+)-gated cation channels, and the transient receptor potential vanilloid 1 channel (TRPV1) is a multimodal cation channel activated by low pH, noxious heat, capsaicin, and voltage. ASICs and TRPV1 are present in sensory neurons. It has been shown that raising the temperature increases TRPV1 and decreases ASIC H(+)-gated current amplitudes. To understand the underlying mechanisms, we have analyzed ASIC and TRPV1 function in a recombinant expression system and in dorsal root ganglion (DRG) neurons at room and physiological temperature. We show that temperature in the range studied does not affect the pH dependence of ASIC and TRPV1 activation. A temperature increase induces, however, a small alkaline shift of the pH dependence of steady-state inactivation of ASIC1a, ASIC1b, and ASIC2a. The decrease in ASIC peak current amplitudes at higher temperatures is likely in part due to the observed accelerated open channel inactivation kinetics and for some ASIC types to the changed pH dependence of steady-state inactivation. The increase in H(+)-activated TRPV1 current at the higher temperature is at least in part due to a hyperpolarizing shift in its voltage dependence. The contribution of TRPV1 relative to ASICs to H(+)-gated currents in DRG neurons increases with higher temperature and acidity. Still, ASICs remain the principal pH sensors of DRG neurons at 35°C in the pH range ≥6.

  17. Behaviour and modelling of aluminium alloy AA6060 subjected to a wide range of strain rates and temperatures

    Directory of Open Access Journals (Sweden)

    Vilamosa Vincent

    2015-01-01

    Full Text Available The thermo-mechanical behaviour in tension of an as-cast and homogenized AA6060 alloy was investigated at a wide range of strains (the entire deformation process up to fracture, strain rates (0.01–750 s−1 and temperatures (20–350 ∘C. The tests at strain rates up to 1 s−1 were performed in a universal testing machine, while a split-Hopkinson tension bar (SHTB system was used for strain rates from 350 to 750 s−1. The samples were heated with an induction-based heating system. A typical feature of aluminium alloys at high temperatures is that necking occurs at a rather early stage of the deformation process. In order to determine the true stress-strain curve also after the onset of necking, all tests were instrumented with a digital camera. The experimental tests reveal that the AA6060 material has negligible strain-rate sensitivity (SRS for temperatures lower than 200 ∘C, while both yielding and work hardening exhibit a strong positive SRS at higher temperatures. The coupled strain-rate and temperature sensitivity is challenging to capture with most existing constitutive models. The paper presents an outline of a new semi-physical model that expresses the flow stress in terms of plastic strain, plastic strain rate and temperature. The parameters of the model were determined from the tests, and the stress-strain curves from the tests were compared with the predictions of the model. Good agreement was obtained over the entire strain rate and temperature range.

  18. Temperature-modulated annealing of c-plane sapphire for long-range-ordered atomic steps

    Science.gov (United States)

    Yatsui, Takashi; Kuribara, Kazunori; Sekitani, Tsuyoshi; Someya, Takao; Yoshimoto, Mamoru

    2016-03-01

    High-quality single-crystalline sapphire is used to prepare various semiconductors because of its thermal stability. Here, we applied the tempering technique, which is well known in the production of chocolate, to prepare a sapphire substrate. Surprisingly, we successfully realised millimetre-range ordering of the atomic step of the sapphire substrate. We also obtained a sapphire atomic step with nanometre-scale uniformity in the terrace width and atomic-step height. Such sapphire substrates will find applications in the preparation of various semiconductors and devices.

  19. Temperature-modulated annealing of c-plane sapphire for long-range-ordered atomic steps

    International Nuclear Information System (INIS)

    Yatsui, Takashi; Kuribara, Kazunori; Sekitani, Tsuyoshi; Someya, Takao; Yoshimoto, Mamoru

    2016-01-01

    High-quality single-crystalline sapphire is used to prepare various semiconductors because of its thermal stability. Here, we applied the tempering technique, which is well known in the production of chocolate, to prepare a sapphire substrate. Surprisingly, we successfully realised millimetre-range ordering of the atomic step of the sapphire substrate. We also obtained a sapphire atomic step with nanometre-scale uniformity in the terrace width and atomic-step height. Such sapphire substrates will find applications in the preparation of various semiconductors and devices. (paper)

  20. Temperature-dependence of soil/air partition coefficients for selected polycyclic aromatic hydrocarbons and organochlorine pesticides over a temperature range of -30 to +30 degrees C.

    Science.gov (United States)

    He, Xin; Chen, Shuo; Quan, Xie; Zhao, Yazhi; Zhao, Huimin

    2009-07-01

    The soil/air partition coefficients (K(SA)) for two polycyclic aromatic carbons (PAHs) and six organochlorine pesticides (OCs) were determined by a solid-phase fugacity meter over a wide temperature range of -30 to +30 degrees C in a paddy field soil. Literature values for PAHs and OCs obtained by the same method were 1.9-5.1 times of present values at +20 degrees C. Experimentally determined K(SA) ranged over six orders of magnitude, with log K(SA) from 4.5 for alpha-hexachlorocyclohexane at +30 degrees C to 10.4 for trans-nonachlor at -20 degrees C. Separate linear regressions of log K(SA) and reciprocal absolute temperature were employed at temperatures above 0 degrees C and below 0 degrees C. The calculated enthalpies associated with the phase transfer from the soil to the air (DeltaH(SA)) over 0 to +30 degrees C range from 78 to 108 kJmol(-1), which are in a good agreement with the literature values.

  1. Synthesis and characterization of Cu-MFI catalyst for the direct medium temperature range NO decomposition

    Directory of Open Access Journals (Sweden)

    Valkaj Karolina Maduna

    2016-03-01

    Full Text Available In this study the physico-chemical and catalytic properties of copper bearing MFI zeolites (Cu-MFI with different Si/Al and Si/Cu ratios were investigated. Two different methods for incorporation of metal ions into the zeolite framework were used: the ion exchange from the solution of copper acetate and the direct hydrothermal synthesis. Direct synthesis of a zeolite in the presence of copper-phosphate complexes was expected to generate more active copper species necessary for the desired reaction than the conventional ion exchange method. Direct decomposition of NO was used as a model reaction, because this reaction still offers a very attractive approach to NOX removal. The catalytic properties of zeolite samples were studied using techniques, such as XRD, SEM, EPR and nitrogen adsorption/desorption measurements at 77 K. Results of the kinetic investigation revealed that both methods are applicable for the preparation of the catalysts with active sites capable of catalyzing the NO decomposition. It was found out that Cu-MFI zeolites obtained through direct synthesis are promising catalysts for NO decomposition, especially at lower reaction temperatures. The efficiency of the catalysts prepared by both methods is compared and discussed.

  2. The creation of high-temperature superconducting cables of megawatt range in Russia

    Science.gov (United States)

    Sytnikov, V. E.; Bemert, S. E.; Krivetsky, I. V.; Romashov, M. A.; Popov, D. A.; Fedotov, E. V.; Komandenko, O. V.

    2015-12-01

    Urgent problems of the power industry in the 21st century require the creation of smart energy systems, providing a high effectiveness of generation, transmission, and consumption of electric power. Simultaneously, the requirements for controllability of power systems and ecological and resource-saving characteristics at all stages of production and distribution of electric power are increased. One of the decision methods of many problems of the power industry is the development of new high-efficiency electrical equipment for smart power systems based on superconducting technologies to ensure a qualitatively new level of functioning of the electric power industry. The intensive research and development of new types of electrical devices based on superconductors are being carried out in many industrialized advanced countries. Interest in such developments has especially increased in recent years owing to the discovery of so-called high-temperature superconductors (HTS) that do not require complicated and expensive cooling devices. Such devices can operate at cooling by inexpensive and easily accessible liquid nitrogen. Taking into account the obvious advantages of superconducting cable lines for the transmission of large power flows through an electrical network, as compared with conventional cables, the Federal Grid Company of Unified Energy System (JSC FGC UES) initiated a research and development program including the creation of superconducting HTS AC and DC cable lines. Two cable lines for the transmitted power of 50 MVA/MW at 20 kV were manufactured and tested within the framework of the program.

  3. Comparison of calculated and experimental thermal attachment rate constants for SF6 in the temperature range 200--6000K

    International Nuclear Information System (INIS)

    Orient, O.J.; Chutjian, A.

    1986-01-01

    Electron-attachment cross sections are calculated for the process e - +SF 6 →SF 6 - in the energy range 1--200 MeV. An electron scattering approximation is used in which diatomic-like potential energy curves near the equilibrium SF 6 ground state are constructed from recent spectroscopic data. Excellent agreement is found over the entire energy range with experimental attachment cross sections at a temperature of 300 0 K for s-wave (l = 0) scattering. The same calculation, with appropriate adjustment of the thermal populations, is used to calculate attachment rate constants k(epsilon-bar) in the range 50--600 0 K for both s- and p-wave scattering. Comparisons are made with four independent sets of measured rate constants in the range 200--600 0 K, after adding an experimental estimate of the attachment rate for the process e - +SF 6 →SF 5 - +F. Good agreement is found with three sets of data, and poorer agreement with the fourth. The calculation shows that the true s-wave behavior of the rate constant, in which k(epsilon-bar) is independent of epsilon-bar, will be realized only at temperatures T less than 115 K, and that the observed constancy in the range 300--600 0 K is accidental. Theory predicts approximately a 9% increase in k(epsilon-bar) as T is lowered from 300 to 200 0 K

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

    Science.gov (United States)

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

    2017-01-01

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

  5. Performance of a 100V Half-Bridge MOSFET Driver, Type MIC4103, Over a Wide Temperature Range

    Science.gov (United States)

    Patterson, Richard L.; Hammoud, Ahmad

    2011-01-01

    The operation of a high frequency, high voltage MOSFET (metal-oxide semiconductor field-effect transistors) driver was investigated over a wide temperature regime that extended beyond its specified range. The Micrel MIC4103 is a 100V, non-inverting, dual driver that is designed to independently drive both high-side and low-side N-channel MOSFETs. It features fast propagation delay times and can drive 1000 pF load with 10ns rise times and 6 ns fall times [1]. The device consumes very little power, has supply under-voltage protection, and is rated for a -40 C to +125 C junction temperature range. The floating high-side driver of the chip can sustain boost voltages up to 100 V. Table I shows some of the device manufacturer s specification.

  6. Molecular characterization and molasses fermentation performance of a wild yeast strain operating in an extremely wide temperature range.

    Science.gov (United States)

    Kopsahelis, Nikolaos; Nisiotou, Aspasia; Kourkoutas, Yiannis; Panas, Panayiotis; Nychas, George J-E; Kanellaki, Maria

    2009-10-01

    Molasses fermentation performance by both a cryotolerant and a thermophilic yeast (strain AXAZ-1) isolated from grapes in Greece was evaluated in an extremely wide temperature range (3-40 degrees C). Sequence analysis of the 5.8S internal transcribed spacer and the D1/D2 ribosomal DNA (rDNA) regions assigned isolate to Saccharomyces cerevisiae. Restriction fragment length polymorphism of the mitochondrial DNA showed that strain AXAZ-1 is genetically divergent compared to other wild strains of Greek origin or commercial yeast starters. Yeast cells growing planktonically were capable of fermentation in a wide temperature spectrum, ranging from 3 degrees C to 38 degrees C. Immobilization of yeast on brewer's spent grains (BSG) improved the thermo-tolerance of the strain and enabled fermentation at 40 degrees C. Time to complete fermentation with the immobilized yeast ranged from 20 days at 3 to 38 h at 40 degrees C. The daily ethanol productivity reached maximum (58.1 g/L) and minimum (2.5 g/L) levels at 30 and 3 degrees C, respectively. The aroma-related compounds' profiles of immobilized cells at different fermentation temperatures were evaluated by using solid phase microextraction (SPME) gas chromatography-mass spectrometry (GC-MS). Molasses fermentation resulted in a high quality fermentation product due to the low concentrations of higher and amyl alcohols at all temperatures tested. Strain AXAZ-1 is very promising for the production of ethanol from low cost raw materials, as it was capable to perform fermentations of high ethanol concentration and productivities in both low and high temperatures.

  7. Long-Range Order and Critical Scattering of Neutrons below the Transition Temperature in β-Brass

    DEFF Research Database (Denmark)

    Als-Nielsen, Jens Aage; Dietrich, O.W.

    1967-01-01

    The temperature dependence of long-range order langPrang has been determined from the temperature variation of a superlattice Bragg reflection. The results fitted a power law langPrang prop (Tc-T)beta with Tc the critical temperature and beta = 0.305plusmn0.005, in agreement with the theoretical...... prediction 0.303 profiles of the (1, 0, 0) superlattice reflection at 15.5 and 2.2deg below Tc. The ratio between the susceptibilities chi+(DeltaT) and chi-(DeltaT) DeltaT deg below and above Tc was found to be 5.5plusmn2.0 at DeltaT = 4.4deg and 8...

  8. Conductance of partially disordered graphene: crossover from temperature-dependent to field-dependent variable-range hopping

    International Nuclear Information System (INIS)

    Cheah, C Y; Jaurigue, L C; Kaiser, A B; Gómez-Navarro, C

    2013-01-01

    We report an analysis of low-temperature measurements of the conductance of partially disordered reduced graphene oxide, finding that the data follow a simple crossover scenario. At room temperature, the conductance is dominated by two-dimensional (2D) electric field-assisted, thermally driven (Pollak–Riess) variable-range hopping (VRH) through highly disordered regions. However, at lower temperatures T, we find a smooth crossover to follow the exp(−E 0 /E) 1/3 field-driven (Shklovskii) 2D VRH conductance behaviour when the electric field E exceeds a specific crossover value E C (T) 2D =(E a E 0 1/3 /3) 3/4 determined by the scale factors E 0 and E a for the high-field and intermediate-field regimes respectively. Our crossover scenario also accounts well for experimental data reported by other authors for three-dimensional disordered carbon networks, suggesting wide applicability. (paper)

  9. Predicting Success of Range-Expanding Coral Reef Fish in Temperate Habitats Using Temperature-Abundance Relationships

    Directory of Open Access Journals (Sweden)

    David J. Booth

    2018-02-01

    Full Text Available An 18-year database of coral reef fish expatriation poleward in South East Australia was used to estimate persistence of coal reef fish recruits on temperate reefs. Surveys have identified over 150 coral reef fish species recruiting to temperate reefs at latitudes of 34°S (Sydney and 60 species to 37°S (Merimbula with 20 and 5 species respectively overwintering in at least 1 year over the study duration. We developed indices of vulnerability of key species to drops in water temperatures, by relating drops in abundances of species to temperature drops. Twenty species were ranked according to their temperature vulnerability. Overall, the families Chaetodontidae (butterflyfishes, Acanthuridae (surgeonfishes, Labridae (wrasses and Pomacetnridae (damselfishes had similar cold-water tolerance. However, there was considerable variability within families, for instance in the Pomacentridae, species from the genus Abudefduf appeared to have better cold-temperature tolerance than the other species. Predicted minimum overwintering temperature varied from 15.6°C to 19.8°C, with some species showing lower Tzero at Merimbula, the more poleward location. There was general concordance between a species' tolerance to cold-water and its tendency to occur as an overwinter but also notable exceptions. So while this work demonstrates the potential utility of tolerance to seasonal temperature drops as a means to predict range expansion capacity of vagrant species, the exceptional cases serve to highlight alternative factors. Specifically, tolerance to seasonal cooling of water is not the only important factor when predicting the range expansion capacity of a species. Factors affecting the general abundance of the vagrants, such as habitat suitability and competitor/predator environments will also be critical where overwinter survival becomes a lottery.

  10. The correlation between dengue incidence and diurnal ranges of temperature of Colombo district, Sri Lanka 2005–2014

    Directory of Open Access Journals (Sweden)

    N. D. B. Ehelepola

    2016-08-01

    Full Text Available Background: Meteorological factors affect dengue transmission. Mechanisms of the way in which different diurnal temperatures, ranging around different mean temperatures, influence dengue transmission were published after 2011. Objective: We endeavored to determine the correlation between dengue incidence and diurnal temperature ranges (DTRs in Colombo district, Sri Lanka, and to explore the possibilities of using our findings to improve control of dengue. Design: We calculated the weekly dengue incidence in Colombo during 2005–2014, after data on all of the reported dengue patients and estimated mid-year populations were collected. We obtained daily maximum and minimum temperatures from two Colombo weather stations, averaged, and converted them into weekly data. Weekly averages of DTR versus dengue incidence graphs were plotted and correlations observed. The count of days per week with a DTR of >7.5°C and 7.5°C with an 8-week lag period, and a positive correlation between dengue incidence and a DTR<7.5°C, also with an 8-week lag. Conclusions: Large DTRs were negatively correlated with dengue transmission in Colombo district. We propose to take advantage of that in local dengue control efforts. Our results agree with previous studies on the topic and with a mathematical model of relative vectorial capacity of Aedes aegypti. Global warming and declining DTR are likely to favor a rise of dengue, and we suggest a simple method to mitigate this.

  11. Temperature range extension of an organically crosslinked polymer system and its successful field application for water and gas shutoff

    Energy Technology Data Exchange (ETDEWEB)

    Vasquez, Julio; Eoff, Larry; Dalrymple, Dwyann [Halliburton, Rio de Janeiro. RJ (Brazil)

    2008-07-01

    Excessive water production from hydrocarbon reservoirs is one of the most serious problems in the oil industry. Water production greatly affects the economic life of producing wells and brings along secondary problems such as sand production, corrosion, and tubular scale. Remediation techniques for controlling water production, generally referred to as conformance control, include the use of polymer systems to reduce or plug permeability to water. This paper presents the laboratory evaluation of an organically crosslinked polymer (OCP) system used as a sealant for water control problems in hydrocarbon wells. Originally, the OCP system had a limited working temperature range (140 deg to 260 deg F). Recently, an alternative base polymer (for low temperatures) and a retarder (for high temperatures) have been introduced to expand the temperature range of applicability of the OCP system from 70 deg F to 350 deg F without compromising its effectiveness or thermal stability. More than 400 jobs have been performed with the OCP system around the world to address conformance problems such as water coning/cresting, high-permeability streaks, gravel pack isolation, fracture shutoff, and casing leak repairs. This paper presents an overview of case histories that used the OCP system in various regions of the world for a wide variety of applications. (author)

  12. A Very Low Dark Current Temperature-Resistant, Wide Dynamic Range, Complementary Metal Oxide Semiconductor Image Sensor

    Science.gov (United States)

    Mizobuchi, Koichi; Adachi, Satoru; Tejada, Jose; Oshikubo, Hiromichi; Akahane, Nana; Sugawa, Shigetoshi

    2008-07-01

    A very low dark current (VLDC) temperature-resistant approach which best suits a wide dynamic range (WDR) complementary metal oxide semiconductor (CMOS) image sensor with a lateral over-flow integration capacitor (LOFIC) has been developed. By implementing a low electric field photodiode without a trade-off of full well-capacity, reduced plasma damage, re-crystallization, and termination of silicon-silicon dioxide interface states in the front end of line and back end of line (FEOL and BEOL) in a 0.18 µm, two polycrystalline silicon, three metal (2P3M) process, the dark current is reduced to 11 e-/s/pixel (0.35 e-/s/µm2: pixel area normalized) at 60 °C, which is the lowest value ever reported. For further robustness at low and high temperatures, 1/3-in., 5.6-µm pitch, 800×600 pixel sensor chips with low noise readout circuits designed for a signal and noise hold circuit and a programmable gain amplifier (PGA) have also been deposited with an inorganic cap layer on a micro-lens and covered with a metal hermetically sealed package assembly. Image sensing performance results in 2.4 e-rms temporal noise and 100 dB dynamic range (DR) with 237 ke- full well-capacity. The operating temperature range is extended from -40 to 85 °C while retaining good image quality.

  13. Production of jet fuel range paraffins by low temperature polymerization of gaseous light olefins using ionic liquid

    International Nuclear Information System (INIS)

    Jiang, Peiwen; Wu, Xiaoping; Zhu, Lijuan; Jin, Feng; Liu, Junxu; Xia, Tongyan; Wang, Tiejun; Li, Quanxin

    2016-01-01

    Graphical abstract: A novel catalytic transformation of light olefins into jet fuel range iso-paraffins by the low-temperature olefin polymerizations under atmospheric conditions. - Highlights: • A novel transformation of light olefins to jet fuel range paraffins was demonstrated. • The synthetic fuels can be produced by atmospheric olefin polymerizations. • C 8 –C 15 iso-paraffins from light olefins was achieved with a selectivity of 80.6%. - Abstract: This work demonstrated a novel catalytic transformation of gaseous olefins into jet fuel range iso-paraffins by the low-temperature olefin polymerizations under atmospheric conditions. The production of the desired C 8 –C 15 iso-paraffins with the selectivity of 80.6 C mol% was achieved by the room-temperature polymerizations of gaseous light olefins using the [BMIM] Al 2 Cl 7 ionic liquid. The influences of the reaction conditions on the olefinic polymerizations were investigated in detail. The properties of hydrocarbons in the synthetic fuels were determined by the GC–MS analyses combined with 1 H NMR, and 13 C NMR analyses. The formation of C 8 –C 15 hydrocarbons from gaseous light olefins was illustrated by the identified products and the functional groups. This transformation potentially provides a useful avenue for the production of the most important components of iso-paraffins required in jet fuels.

  14. Characterization of thermochromic VO2 (prepared at 250 °C) in a wide temperature range by spectroscopic ellipsometry

    Science.gov (United States)

    Houska, J.; Kolenaty, D.; Rezek, J.; Vlcek, J.

    2017-11-01

    The paper deals with thermochromic VO2 prepared by reactive high-power impulse magnetron sputtering and characterized by spectroscopic ellipsometry. We focus on the dispersion of optical constants in a wide temperature range and on the transmittance predicted using the optical constants. While the thermochromic behavior of VO2 in itself has been reported previously (particularly above the room temperature, RT), in this paper we present (i) optical properties achieved at a low deposition temperature of 250 °C and without any substrate bias voltage (which dramatically increases the application potential of the coating) and (ii) changes of these properties not only above but also below RT (down to -30 °C). The properties include very low (for VO2) extinction coefficient at RT (0.10 at 550 nm), low transition temperature of around or even below 50 °C (compared to the frequently cited 68 °C) and high modulation of the predicted infrared transmittance (e.g. 39% at -30 °C, 30% at RT and 3.4% above the transition temperature at 2000 nm for a 100 nm thick coating on glass). The results are important for the design of thermochromic coatings, and pathways for their preparation under industry-friendly conditions, for various technological applications.

  15. Improvement of Surface Temperature Prediction Using SVR with MOGREPS Data for Short and Medium range over South Korea

    Science.gov (United States)

    Lim, S. J.; Choi, R. K.; Ahn, K. D.; Ha, J. C.; Cho, C. H.

    2014-12-01

    As the Korea Meteorology Administration (KMA) has operated Met Office Global and Regional Ensemble Prediction System (MOGREPS) with introduction of Unified Model (UM), many attempts have been made to improve predictability in temperature forecast in last years. In this study, post-processing method of MOGREPS for surface temperature prediction is developed with machine learning over 52 locations in South Korea. Past 60-day lag time was used as a training phase of Support Vector Regression (SVR) method for surface temperature forecast model. The selected inputs for SVR are followings: date and surface temperatures from Numerical Weather prediction (NWP), such as GDAPS, individual 24 ensemble members, mean and median of ensemble members for every 3hours for 12 days.To verify the reliability of SVR-based ensemble prediction (SVR-EP), 93 days are used (from March 1 to May 31, 2014). The result yielded improvement of SVR-EP by RMSE value of 16 % throughout entire prediction period against conventional ensemble prediction (EP). In particular, short range predictability of SVR-EP resulted in 18.7% better RMSE for 1~3 day forecast. The mean temperature bias between SVR-EP and EP at all test locations showed around 0.36°C and 1.36°C, respectively. SVR-EP is currently extending for more vigorous sensitivity test, such as increasing training phase and optimizing machine learning model.

  16. Screening of Metarhizium and Beauveria spp. conidia with exposure to simulated sunlight and a range of temperatures

    International Nuclear Information System (INIS)

    Morley-Davies, J.; Moore, D.; Prior, C.

    1996-01-01

    Conidia of 14 isolates of the entomopathogenic fungi Beauveria bassiana, Metarhizium flavoviride and M. anisopliae were formulated by suspending in paraffinic oil or as dry powder. Non-indicating silica gel was added to both formulations which were stored at 13 °C for at least 2 wk before exposure to a range of temperatures: −10°, 10°, 20°, 30°, 40° and 50° to determine the effects of temperature of storage on viability. At 50° the isolate studied in most detail (M. flavoviride, IMI 330189) initially showed a gradual decline in viability with 73% germination for oil samples after 60 d from an initial level of 93%, whereas the dry samples typically showed higher germination rates (initially 96% germination, dropping to 80% after 60 d). Subsequently there was a rapid decline and both oil formulated and dry conidia had lost almost all viability by 90 d. Samples of IMI 330189 stored dry or in oil, at 40° and below showed > 79% germination after 90 d. M. flavoviride 191–660 exhibited the highest temperature tolerance with >40% germination of the dry stored conidia after 90 d at 50°. Some isolates of both B. bassiana and Metarhizium spp. showed markedly lower tolerance of high temperatures. Samples stored dry usually showed greater percentage germination than samples in oil for all isolates, at all temperatures. The isolates were also exposed to 4, 8, 16 and 24 h uv light from a sunlight simulator at 40°. Conidial viability decreased markedly in all isolates with increasing uv exposure. Germination ranged between 10 and 50% after 24 h exposure to uv, 191–660 retaining highest viability. (author)

  17. The exotic invasive plant Vincetoxicum rossicum is a strong competitor even outside its current realized climatic temperature range

    Directory of Open Access Journals (Sweden)

    Laurа Sanderson

    2013-03-01

    Full Text Available Dog-strangling vine (Vincetoxicum rossicum is an exotic plant originating from Central and Eastern Europe that is becoming increasingly invasive in southern Ontario, Canada. Once established, it successfully displaces local native plant species but mechanisms behind this plant’s high competitive ability are not fully understood. It is unknown whether cooler temperatures will limit the range expansion of V. rossicum, which has demonstrated high tolerance for other environmental variables such as light and soil moisture. Furthermore, if V. rossicum can establish outside its current climatic limit it is unknown whether competition with native species can significantly contribute to reduce fitness and slow down invasion. We conducted an experiment to test the potential of V. rossicum to spread into northern areas of Ontario using a set of growth chambers to simulate southern and northern Ontario climatic temperature regimes. We also tested plant-plant competition by growing V. rossicum in pots with a highly abundant native species, Solidago canadensis, and comparing growth responses to plants grown alone. We found that the fitness of V. rossicum was not affected by the cooler climate despite a delay in reproductive phenology. Growing V. rossicum with S. canadensis caused a significant reduction in seedpod biomass of V. rossicum. However, we did not detect a temperature x competition interaction in spite of evidence for adaptation of S. canadensis to cooler temperature conditions. We conclude that the spread of V. rossicum north within the tested range is unlikely to be limited by climatic temperature but competition with an abundant native species may contribute to slow it down.

  18. Comparison of thermal properties of fish collagen and bovine collagen in the temperature range 298-670K.

    Science.gov (United States)

    Gauza-Włodarczyk, Marlena; Kubisz, Leszek; Mielcarek, Sławomir; Włodarczyk, Dariusz

    2017-11-01

    The increased interest in fish collagen is a consequence of the risk of exposure to Creutzfeld-Jacob disease (CJD) and the bovine spongiform encephalopathy (BSE), whose occurrence is associated with prions carried by bovine collagen. Collagen is the main biopolymer in living organisms and the main component of the skin and bones. Until the discovery of the BSE, bovine collagen had been widely used. The BSE epidemic increased the interest in new sources of collagen such as fish skin collagen (FSC) and its properties. Although the thermal properties of collagen originating from mammals have been well described, less attention has been paid to the thermal properties of FSC. Denaturation temperature is a particularly important parameter, depending on the collagen origin and hydration level. In the reported experiment, the free water and bound water release processes along with thermal denaturation process were studied by means of the differential scanning calorimetry (DSC). Measurements were carried out using a DSC 7 instrument (Elmer-Perkin), in the temperature range 298-670K. The study material was FSC derived by acidic hydration method. The bovine Achilles tendon (BAT) collagen type I was used as the control material. The thermograms recorded revealed both, exothermic and endothermic peaks. For both materials, the peaks in the temperature range of 330-360K were assigned to the release of free water and bound water. The denaturation temperatures of FSC and BAT collagen were determined as 420K and 493K, respectively. Thermal decomposition process was observed at about 500K for FSC and at about 510K for BAT collagen. These results show that FSC is less resistant to high temperature than BAT collagen. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. PEM fuel cells operated at 0% relative humidity in the temperature range of 23-120 oC

    International Nuclear Information System (INIS)

    Zhang, Jianlu; Tang, Yanghua; Song, Chaojie; Cheng, Xuan; Zhang, Jiujun; Wang, Haijiang

    2007-01-01

    Operation of a proton exchange membrane (PEM) fuel cell without external humidification (or 0% relative humidity, abbreviated as 0% RH) of the reactant gases is highly desirable, because it can eliminate the gas humidification system and thus decrease the complexity of the PEM fuel cell system and increase the system volume power density (W/l) and weight power density (W/kg). In this investigation, a PEM fuel cell was operated in the temperature range of 23-120 o C, in particular in a high temperature PEM fuel cell operation range of 80-120 o C, with dry reactant gases, and the cell performance was examined according to varying operation parameters. An ac impedance method was used to compare the performance at 0% RH with that at 100% RH; the results suggested that the limited proton transfer process to the Pt catalysts, mainly in the inonomer within the membrane electrode assembly (MEA) could be responsible for the performance drop. It was demonstrated that operating a fuel cell using a commercially available membrane (Nafion (registered) 112) is feasible under certain conditions without external humidification. However, the cell performance at 0% RH decreased with increasing operation temperature and reactant gas flow rate and decreasing operation pressure

  20. Thermoregulation during flight: body temperature and sensible heat transfer in free-ranging Brazilian free-tailed bats (Tadarida brasiliensis).

    Science.gov (United States)

    Reichard, Jonathan D; Fellows, Spenser R; Frank, Alexander J; Kunz, Thomas H

    2010-01-01

    Bat wings are important for thermoregulation, but their role in heat balance during flight is largely unknown. More than 80% of the energy consumed during flight generates heat as a by-product, and thus it is expected that bat wings should dissipate large amounts of heat to prevent hyperthermia. We measured rectal (T(r)) and surface (T(s)) temperatures of Brazilian free-tailed bats (Tadarida brasiliensis) as they emerged from and returned to their daytime roosts and calculated sensible heat transfer for different body regions (head, body, wings, and tail membrane). Bats' T(r) decreased from 36.8°C during emergence flights to 34.4°C during returns, and T(s) scaled positively with ambient temperature (T(a)). Total radiative heat loss from bats was significantly greater for a radiative sink to the night sky than for a sink with temperature equal to T(a). We found that free-ranging Brazilian free-tailed bats, on average, do not dissipate heat from their wings by convection but instead dissipate radiative heat (L) to the cloudless night sky during flight ([Formula: see text] W). However, within the range of T(a) measured in this study, T. brasiliensis experienced net heat loss between evening emergence and return flights. Regional hypothermia reduces heat loss from wings that are exposed to potentially high convective fluxes. Additional research is needed to establish the role of wings in evaporative cooling during flight in bats.

  1. Thermal properties of Nb from acoustic and electrical resistivity measurements in the temperature range 60--340 K

    International Nuclear Information System (INIS)

    Cannelli, G.; Cannelli, G.B.

    1976-01-01

    The thermal diffusivity and the relative difference in molar heat capacities, (C/subp/-C/subv/)/C/subv/, of polycrystalline niobium have been derived from acoustic measurements in the temperature range 60--340 K. The electrical resistivity has also been measured from 8 to 340 K; 0.833 μΩ cm, 18.7, and 9.25 K being the values of residual resistivity rho 0 , resistance ratio rho (300 K)/rho 0 , and superconducting transition temperature, respectively. The thermal conductivity, Lorenz ratio, and molar heat capacity at constant volume have been calculated for the temperature range 60--340 K, using present values of thermal diffusivity, electrical resistivity, and literature values of specific heat C/subp/. A shallow maximum in the derived thermal conductivity curve is observed around 180 K where the Lorenz ratio assumes the maximum value 3.15x10 -8 W Ω K -2 . It is suggested that the thermal conductivity maximum may originate in the phonon contribution

  2. Influence of temperature on the critical in-plane field range for VBLs in the walls of hard domains

    International Nuclear Information System (INIS)

    Nie, X.F.; Guo, G.X.; Xu, J.P.; Liu, S.P.; Wang, L.N.; Huo, S.G.

    2006-01-01

    The influence of temperature on the critical in-plane field range for vertical Bloch lines in the walls of three kinds of hard domains is investigated experimentally. It is found that for each kind of three hard domains, there exists a critical in-plane field range, i. e. [H ip (1) (T),H ip (2) (T)], which depends on temperatures and in which vertical Bloch lines are unstable. Here, H ip (1) (T) is the initial critical in-plane field where VBLs in the walls of three kinds of hard domains are annihilated, and H ip (2) (T) is the lowest in-plane field where VBLs in their corresponding hard domains are annihilated completely. H ip (1) (T), H ip (2) (T) and [H ip (1) (T),H ip (2) (T)], all decrease as the temperature increase. Furthermore, H ip (1) (T) and H ip (2) (T) reach zero at T 0 1 and T 0 , respectively. In addition, there exists a relationship among them, when T is unchanged, H ip (1) (T) of the three kinds of hard domains (ordinary hard bubbles (OHB), first kind of dumbbell domain (ID) and second kind of dumbbell domains (IID)) decrease successively, and theirH ip (2) (T) are the same

  3. The association between diurnal temperature range and childhood hand, foot, and mouth disease: a distributed lag non-linear analysis.

    Science.gov (United States)

    Yin, Fei; Ma, Yue; Zhao, Xing; Lv, Qiang; Liu, Yaqiong; Zhang, Tao; Li, Xiaosong

    2017-11-01

    In recent years, hand, foot, and mouth disease (HFMD) has been increasingly recognized as a critical challenge to disease control and prevention in China. Previous studies have found that meteorological factors such as mean temperature and relative humidity were associated with HFMD. However, little is known about whether the diurnal temperature range (DTR) has any impact on HFMD. This study aimed to quantify the impact of DTR on childhood HFMD in 18 cities in Sichuan Province. A distributed lag non-linear model was adopted to explore the temporal lagged association of daily temperature with age-, gender- and pathogen-specific HFMD. A total of 290 123 HFMD cases aged 0-14 years were reported in the 18 cities in Sichuan Province. The DTR-HFMD relationships were non-linear in all subgroups. Children aged 6-14 years and male children were more vulnerable to the temperature changes. Large DTR had the higher risk estimates of HFMD incidence in cases of EV71 infection, while small DTR had the higher risk estimates of HFMD incidence in cases of CV-A16 infection. Our study suggested that DTR played an important role in the transmission of HFMD with non-linear and delayed effects.

  4. The unlubricated reciprocating sliding wear of 316 stainless steel in C02 in the temperature range 20 to 6000C

    International Nuclear Information System (INIS)

    Smith, A.F.

    1985-11-01

    The friction and wear behaviour of 316 stainless steel in C0 2 has been investigated in the load range 8 - 5ON from 20 to 600 0 C. Wear transitions occurred at all temperatures but were load dependent. At and below 300 0 C wear transitions only took place at low leads whereas above 300 0 C transitions were seen al all loads. The low temperature wear transition, giving an order of magnitude decrease in wear rate was associated with a change in friction behaviour. The friction force across the specimen was initially widely fluctuating and varied from cycle to cycle. After a time, which did not necessarily coincide with the wear transition the cyclic variation in the friction force become much less. This smoother sliding is thought to indicate a trend to oxide -oxide contacts. At higher temperatures wear transitions result in a two orders of magnitude reduction in wear. The corresponding friction transition was similar to the low temperature friction change but also included a marked temporary drop in the coefficient of friction. (author)

  5. Nucleation and swelling in electron irradiated austenitic stainless steels in temperature range 400∼720 degree C

    International Nuclear Information System (INIS)

    Qian Jiapu; Lu Liping; Chen Jiming; Sun Jiguang; Zhao Zhuoyong

    1994-10-01

    A study of the influence of temperature on swelling behavior in electron irradiated austenitic stainless steels has been performed with a high voltage electron microscope (HVEM) in the temperature range 400 to 720 degree C. The specimen materials were solution annealed (SA) 316 stainless steel (SS), cold worked (CW) 316 SS and Ti-modified austenitic stainless steel (Ti-mod. SS). The electron energy in HVEM was 1 MeV. The results of mean void density, mean void diameter, void swelling, swelling rate and incubation dose vs. dose and temperature are presented. It is suggested that the irradiation temperature influenced the microstructure, overall sink strength and relative strength of neutral sinks to that of biased sinks in the specimens and so made the void nucleation, void growth and swelling behavior differently in 316 SA, 316 CW and Ti-mod. SS. The influence of He pre-implantation on void nucleation in electron irradiated austenitic stainless steels has also been studied. The experiments indicated that the helium was active void nucleus but had no direct impact on void growth

  6. Analysis of I-V characteristics on Au/n-type GaAs Schottky structures in wide temperature range

    Energy Technology Data Exchange (ETDEWEB)

    Karatas, S. [Department of Physics, Faculty of Sciences and Arts, University of Kahramanmaras Suetcue Imam, Kahramanmaras 46100 (Turkey)]. E-mail: skaratas@ksu.edu.tr; Altindal, S. [Department of Physics, Faculty of Sciences and Arts, Gazi University, 06500 Besevler, Ankara (Turkey)

    2005-09-15

    The current-voltage (I-V) characteristics of Au/n-GaAs Schottky barrier diodes (SBD) were determined in the temperature range 80-400K. SBD parameters such as ideality factor n, series resistance R{sub S} and barrier height {phi}{sub b} were extracted from I-V curves using Cheung's method. The barrier height for current transport decreases and the ideality factor increases with the decrease temperatures. Such behavior is attributed to barrier inhomogeneities by assuming a Gaussian distribution of barrier heights at the interface. So that barrier height {phi}{sub I-V} have been corrected by taking into account quality factors (n) and the electron tunneling factor ({alpha}{chi}{sup 1/2}{delta}) in the expression of saturation current (I{sub 0}) of the Au/n-GaAs Schottky diodes. Thus, a modified ln(I{sub 0}/T{sup 2})-q{sup 2}{sigma}{sub 0}{sup 2}/2k{sup 2}T{sup 2} versus 1/T gives {phi}-bar {sub b0}(T=0) and A{sup *} as 0.73eV and 11.08A/(cm{sup 2}K{sup 2}), respectively, without using the temperature coefficient of the barrier heights. Therefore, it has been concluded that the temperature dependent I-V characteristics of the device can be successfully explained with Gaussian distribution of the BHs.

  7. Impacts of Initial Soil Moisture and Vegetation on the Diurnal Temperature Range in Arid and Semiarid Regions in China

    Science.gov (United States)

    Yuan, Guanghui; Zhang, Lei; Liang, Jiening; Cao, Xianjie; Guo, Qi; Yang, Zhaohong

    2017-11-01

    To assess the impacts of initial soil moisture (SMOIS) and the vegetation fraction (Fg) on the diurnal temperature range (DTR) in arid and semiarid regions in China, three simulations using the weather research and forecasting (WRF) model are conducted by modifying the SMOIS, surface emissivity and Fg. SMOIS affects the daily maximum temperature (Tmax) and daily minimum temperature (Tmin) by altering the distribution of available energy between sensible and latent heat fluxes during the day and by altering the surface emissivity at night. Reduced soil wetness can increase both the Tmax and Tmin, but the effect on the DTR is determined by the relative strength of the effects on Tmax and Tmin. Observational data from the Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL) and the Shapotou Desert Research and Experimental Station (SPD) suggest that the magnitude of the SMOIS effect on the distribution of available energy during the day is larger than that on surface emissivity at night. In other words, SMOIS has a negative effect on the DTR. Changes in Fg modify the surface radiation and the energy budget. Due to the depth of the daytime convective boundary layer, the temperature in daytime is affected less than in nighttime by the radiation and energy budget. Increases in surface emissivity and decreases in soil heating resulting from increased Fg mainly decrease Tmin, thereby increasing the DTR. The effects of SMOIS and Fg on both Tmax and Tmin are the same, but the effects on DTR are the opposite.

  8. Phase diagram of Ti-B-C system in the temperature range of 300-3500 K

    International Nuclear Information System (INIS)

    Gusev, A.I.

    1996-01-01

    Calculation of phase equilibrium in the ternary system Ti-B-C in the areas of the TiC y -TiB 2 and B 4 C y -TiB 2 cross sections as well as partial construction of three-dimensional (spatial)diagram of the Ti-B-C system within the temperature range of 300-3500 K is carried out. The form of the isothermal cross section of the ternary system remains almost unchanged up to 1900 K. The most essential change is related to disordering of the low-temperature ordered phases Ti 2 C, Ti 3 C and Ti 6 C 5 of the titanium carbide at T > 950 K [ru

  9. Elastic constants of neodymium single crystals in the temperature range 4.2--300 degreeK

    International Nuclear Information System (INIS)

    Greiner, J.D.; Schlader, D.M.; McMasters, O.D.; Gschneidner, K.A. Jr.; Smith, J.F.

    1976-01-01

    The elastic constants of a single crystal of the double hcp allotrope of neodymium have been measured over the temperature range 4.2--300 degreeK. The magnetic orderings which occur in neodymium near 7.5 and 19 degreeK are readily evident as cusps in the temperature dependences of some of the directly measured ultrasonic wave velocities, as well as in the associated elastic constants, and the character of the magnetic interactions is reflected in the differing effects on the various elastic constants. Comparison of the elastic constants of neodymium with those of seven other rare earths shows a trend with atomic number which is similar to trends which have been observed in other physical properties

  10. Realization of the ITS-90 over the Temperature Range 83 K to 693 K at the National Institute for Standards NIS-Egypt

    Science.gov (United States)

    Gamal, M.; Ali, K.; Moussa, M. R.

    2003-09-01

    The thermometry group of the National Institute for Standards (NIS) has realized the International Temperature Scale 1990 (ITS-90), as defined over the temperature range from 83 K to 2200 °C. This work concerns the temperature range from 83 K up to 693 K only. A brief review is given of the techniques and apparatus used, the source and purity of the fixed points in this range, cell designs and uncertainties of our realization.

  11. Elevation-dependent temperature trends in the Rocky Mountain Front Range: changes over a 56- and 20-year record.

    Directory of Open Access Journals (Sweden)

    Chris R McGuire

    Full Text Available Determining the magnitude of climate change patterns across elevational gradients is essential for an improved understanding of broader climate change patterns and for predicting hydrologic and ecosystem changes. We present temperature trends from five long-term weather stations along a 2077-meter elevational transect in the Rocky Mountain Front Range of Colorado, USA. These trends were measured over two time periods: a full 56-year record (1953-2008 and a shorter 20-year (1989-2008 record representing a period of widely reported accelerating change. The rate of change of biological indicators, season length and accumulated growing-degree days, were also measured over the 56 and 20-year records. Finally, we compared how well interpolated Parameter-elevation Regression on Independent Slopes Model (PRISM datasets match the quality controlled and weather data from each station. Our results show that warming signals were strongest at mid-elevations over both temporal scales. Over the 56-year record, most sites show warming occurring largely through increases in maximum temperatures, while the 20-year record documents warming associated with increases in maximum temperatures at lower elevations and increases in minimum temperatures at higher elevations. Recent decades have also shown a shift from warming during springtime to warming in July and November. Warming along the gradient has contributed to increases in growing-degree days, although to differing degrees, over both temporal scales. However, the length of the growing season has remained unchanged. Finally, the actual and the PRISM interpolated yearly rates rarely showed strong correlations and suggest different warming and cooling trends at most sites. Interpretation of climate trends and their seasonal biases in the Rocky Mountain Front Range are dependent on both elevation and the temporal scale of analysis. Given mismatches between interpolated data and the directly measured station data

  12. Thermo-economic optimization of heat recovery steam generator for a range of gas turbine exhaust temperatures

    International Nuclear Information System (INIS)

    Nadir, Mahmoud; Ghenaiet, Adel; Carcasci, Carlo

    2016-01-01

    Highlights: • Thermo-economic optimization of HRSG configurations. • The maximum value of the net present value was targeted for the economic optimization. • Three level HRSG is the best option in respect of power output and high priced medium. • Two level HRSG is the best for net benefit in low and intermediate priced mediums. - Abstract: This paper illustrates the effect of selling price on the optimum design parameters of a heat recovery steam generator (HRSG) and the selection of its ideal configuration for an outlet temperature range of 350–650 °C. The Particle Swarm Optimization (PSO) method was used, considering the steam cycle specific work as an objective to be maximized, the net present value as another objective to be maximized for the economic optimization and a combination of both. Three configurations of heat recovery steam generators are considered with one, two and three pressure levels and a reheat. The results show that, the three pressure level system is the best configuration from a thermodynamic point of view, but with respect to the economical aspect the two pressure levels is the best configuration for the low and medium selling prices (0.04 $/kW h, 0.08 $/kW h and 0.2 $/kW h), whereas the three pressure level configuration would only be interesting for a high selling price of 0.3 $/kW h and a temperature range 450–600 °C. For a temperature of 650 °C, the high cost of the three level system leads to a decrease in the net present value. As the selling price increases the optimized design parameters of the three pressure level HRSG based on economic or thermodynamic optimization are similar. The obtained results are used to elaborate a new correlation relating the net present value with the gas turbine outlet temperature, gas mass flow rate, number of levels of HRSG and selling price.

  13. Infrared normal spectral emissivity of Ti–6Al–4V alloy in the 500–1150 K temperature range

    International Nuclear Information System (INIS)

    González-Fernández, L.; Risueño, E.; Pérez-Sáez, R.B.; Tello, M.J.

    2012-01-01

    Highlights: ► First heating cycle acts as a annealing, relieving the surface stresses. ► Stress relieving occurs mainly above 900 K. ► Emissivity decreases between 0.35 and 0.10 in the 2.5–22 μm spectral range. ► Emissivity increases linearly with temperature, with the same slope for λ > 10 μm. ► Good agreement between resistivity and emissivity by means of Hagen–Rubens relation. - Abstract: Thermal radiative emissivity is related to the optical and electrical properties of materials, and it is a key parameter required in a large number of industrial applications. In the case of Ti–6Al–4V, spectral emissivity experimental data are not available for the range of temperatures between 400 and 1200 K, where almost all industrial applications take place. The experimental results in this paper show that the normal spectral emissivity decreases with wavelength from a value of about 0.35 at 2.5 μm to about 0.10 at 22 μm. At the same time, the spectral emissivity shows a slight linear increase with temperature between 500 and 1150 K, with approximately the same slope for all wavelengths. Additionally, the influence of the samples thermal history on the emissivity is studied. A strong decrease in the emissivity values appears due to the effect of surface stress relaxation processes. This means that the radiative properties of this alloy strongly depend on the surface stress state. A thermal treatment to relieve the surface stress should be carried out to achieve a steady state of the radiative properties. In addition, a good qualitative agreement is found between the temperature dependence of the electrical resistivity obtained using conventional measurements and the one obtained from the emissivity experimental results by using the Hagen–Rubens equation.

  14. Ab initio molecular dynamics study of fluid H2O-CO2 mixture in broad pressure-temperature range

    Directory of Open Access Journals (Sweden)

    Jie Fu

    2017-11-01

    Full Text Available Properties of H2O and CO2 fluid and their mixtures under extreme pressures and temperatures are poorly known yet critically important in a number of applications. Several hundreds of first-principles molecular dynamics (FPMD runs have been performed to obtain the pressure-volume-temperature (P-V-T data on supercritical H2O, CO2, and H2O-CO2 mixtures. The pressure-temperature (P-T range are from 0.5 GPa to 104 GPa (48.5 GPa for CO2 and from 600 K to 4000 K. Based on these data, we evaluate several existing equations of state (EOS for the fluid H2O, CO2, and H2O-CO2 mixture. The results show that the EOS for H2O from Belonoshko et al. [Geochim. Cosmochim. Acta 55, 381–387; Geochim. Cosmochim. Acta 55, 3191–3208; Geochim. Cosmochim. Acta 56, 3611–3626; Comput. Geosci. 18, 1267–1269] not only can be used in the studied P-T range but also is accurate enough to be used for prediction of P-V-T data. In addition, IAPWS-95 EOS for H2O shows excellent extrapolation behavior beyond 1.0 GPa and 1273 K. However, for the case of CO2, none of the existing EOS produces data in agreement with the FPMD results. We created new EOS for CO2. The precision of the new EOS is tested by comparison to the calculated P-V-T data, fugacity coefficient of the CO2 fluid derived from high P-T experimental data as well as to the (very scarce experimental volumetric data in the high P-T range. On the basis of our FPMD data we created a new EOS for H2O-CO2 mixture. The new EOS for the mixture is in reasonable agreement with experimental data.

  15. Ab initio molecular dynamics study of fluid H2O-CO2 mixture in broad pressure-temperature range

    Science.gov (United States)

    Fu, Jie; Zhao, Jijun; Plyasunov, Andrey V.; Belonoshko, Anatoly B.

    2017-11-01

    Properties of H2O and CO2 fluid and their mixtures under extreme pressures and temperatures are poorly known yet critically important in a number of applications. Several hundreds of first-principles molecular dynamics (FPMD) runs have been performed to obtain the pressure-volume-temperature (P-V-T) data on supercritical H2O, CO2, and H2O-CO2 mixtures. The pressure-temperature (P-T) range are from 0.5 GPa to 104 GPa (48.5 GPa for CO2) and from 600 K to 4000 K. Based on these data, we evaluate several existing equations of state (EOS) for the fluid H2O, CO2, and H2O-CO2 mixture. The results show that the EOS for H2O from Belonoshko et al. [Geochim. Cosmochim. Acta 55, 381-387; Geochim. Cosmochim. Acta 55, 3191-3208; Geochim. Cosmochim. Acta 56, 3611-3626; Comput. Geosci. 18, 1267-1269] not only can be used in the studied P-T range but also is accurate enough to be used for prediction of P-V-T data. In addition, IAPWS-95 EOS for H2O shows excellent extrapolation behavior beyond 1.0 GPa and 1273 K. However, for the case of CO2, none of the existing EOS produces data in agreement with the FPMD results. We created new EOS for CO2. The precision of the new EOS is tested by comparison to the calculated P-V-T data, fugacity coefficient of the CO2 fluid derived from high P-T experimental data as well as to the (very scarce) experimental volumetric data in the high P-T range. On the basis of our FPMD data we created a new EOS for H2O-CO2 mixture. The new EOS for the mixture is in reasonable agreement with experimental data.

  16. Recrystallization kinetics of warm-rolled tungsten in the temperature range 1150-1350 °C

    DEFF Research Database (Denmark)

    Alfonso Lopez, Angel; Juul Jensen, Dorte; Luo, G.-N.

    2014-01-01

    in the mechanical properties during annealing are quantified by Vickers hardness measurements. They are described concisely by classical kinetic models for recovery and recrystallization. The observed time spans for recrystallization and the obtained value for the activation energy of the recrystallization process...... degradation in material properties as a loss in mechanical strength and embrittlement. The thermal stability of a pure tungsten plate warm-rolled to 67% thickness reduction was investigated by long-term isothermal annealing in the temperature range between 1150 °C and 1350 °C up to 2200 h. Changes...

  17. Thermodynamic Properties of Low-Density {}^{132}Xe Gas in the Temperature Range 165-275 K

    Science.gov (United States)

    Akour, Abdulrahman

    2018-01-01

    The method of static fluctuation approximation was used to calculate selected thermodynamic properties (internal energy, entropy, energy capacity, and pressure) for xenon in a particularly low-temperature range (165-270 K) under different conditions. This integrated microscopic study started from an initial basic assumption as the main input. The basic assumption in this method was to replace the local field operator with its mean value, then numerically solve a closed set of nonlinear equations using an iterative method, considering the Hartree-Fock B2-type dispersion potential as the most appropriate potential for xenon. The results are in very good agreement with those of an ideal gas.

  18. Dielectric and thermophysical properties of different beef meat blends over a temperature range of -18 to +10°C.

    Science.gov (United States)

    Farag, K W; Lyng, J G; Morgan, D J; Cronin, D A

    2008-08-01

    Dielectric and thermophysical properties of three different beef meat blends (lean, fat and 50:50 mixture) were evaluated over a range of temperatures from -18 to +10°C. In the region of thawing (-3 to -1°C), dielectric constant (ε') and dielectric loss factor (ε') values for radio frequency (RF) and microwave (MW) were significantly higher (Pthermal conductivity (k), specific heat (c) and thermal diffusivity (α) also showed significant changes (Pfood technologists in the context of rapid defrosting of meat products.

  19. Biases in the diurnal temperature range in Central Europe in an ensemble of regional climate models and their possible causes

    Czech Academy of Sciences Publication Activity Database

    Kyselý, Jan; Plavcová, Eva

    2012-01-01

    Roč. 39, č. 6 (2012), s. 1275-1286 ISSN 0930-7575 R&D Projects: GA ČR GAP209/10/2265 Grant - others:ENSEMBLES: EU-FP6(XE) 505539 Program:FP6 Institutional support: RVO:68378289 Keywords : Regional climate models * ENSEMBLES * Diurnal temperature range * Atmospheric circulation * Cloud cover * Central Europe Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 4.231, year: 2012 http://link.springer.com/article/10.1007/s00382-011-1200-4

  20. Live cell plasma membranes do not exhibit a miscibility phase transition over a wide range of temperatures.

    Science.gov (United States)

    Lee, Il-Hyung; Saha, Suvrajit; Polley, Anirban; Huang, Hector; Mayor, Satyajit; Rao, Madan; Groves, Jay T

    2015-03-26

    Lipid/cholesterol mixtures derived from cell membranes as well as their synthetic reconstitutions exhibit well-defined miscibility phase transitions and critical phenomena near physiological temperatures. This suggests that lipid/cholesterol-mediated phase separation plays a role in the organization of live cell membranes. However, macroscopic lipid-phase separation is not generally observed in cell membranes, and the degree to which properties of isolated lipid mixtures are preserved in the cell membrane remain unknown. A fundamental property of phase transitions is that the variation of tagged particle diffusion with temperature exhibits an abrupt change as the system passes through the transition, even when the two phases are distributed in a nanometer-scale emulsion. We support this using a variety of Monte Carlo and atomistic simulations on model lipid membrane systems. However, temperature-dependent fluorescence correlation spectroscopy of labeled lipids and membrane-anchored proteins in live cell membranes shows a consistently smooth increase in the diffusion coefficient as a function of temperature. We find no evidence of a discrete miscibility phase transition throughout a wide range of temperatures: 14-37 °C. This contrasts the behavior of giant plasma membrane vesicles (GPMVs) blebbed from the same cells, which do exhibit phase transitions and macroscopic phase separation. Fluorescence lifetime analysis of a DiI probe in both cases reveals a significant environmental difference between the live cell and the GPMV. Taken together, these data suggest the live cell membrane may avoid the miscibility phase transition inherent to its lipid constituents by actively regulating physical parameters, such as tension, in the membrane.

  1. Properties of simulated welded joints of Cr-Mo steel following heat treatment in intercritical temperature range

    International Nuclear Information System (INIS)

    Sabun, L.B.; Vornovitskij, I.N.; Lukicheva, S.V.; Melamed, S.Eh.

    1975-01-01

    The parameters are determined of the welded joints heat treatment which permit to shorten the holp-up period due to the accelerating the process of the weld-stress release and the diffusion of carbon and alloying elements resulting in the equilibration of the weld metal chemical composition. The properties of an imitated welded joint of the 15KHM steel have been studied after various modes of heat treatment. The critical points are 740 and 875 deg C. The mechanical properties determination and the study of the strain hardening process are carried out with a high-temperature metallography plant. The modes of a low-temperature tempering and incomplete annealing are investigated within an intercritical range at temperatures of 750 to 780 deg C and a hold-up periods of to five minutes with a consecutive cooling in air or with the furnace respectively. The results of the studies have shown that with the decrease in the heat treatment temperature the strength, plasticity and also hardness of the welded joint zones prove to be to the standard of a sample treated conforming to the high tempering mode. In case of an incomplete annealing (770 to 780 deg C) the strength of the welded joint is maintained to the standard of the strength obtained at the high tempering, and the relative elongation value increases considerably at all the hold-up periods investigated. The strain-hardening process for the low-temperature normalizing and high tempering proceeds approximately equally. The fracture occurs at the deformation of 30 to 35% in microvolume, the relative elongation in that case being 12 to 13%

  2. Characteristic dielectric behaviour of the wide temperature range twist grain boundary phases of unsymmetrical liquid crystal dimers

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, M B [Physics Department, University of Allahabad, Allahabad-211 002 (India); Dhar, R [Physics Department, University of Allahabad, Allahabad-211 002 (India); Achalkumar, A S [Centre for Liquid Crystal Research, Jalahalli, Bangalore-560 103 (India); Yelamaggad, C V [Centre for Liquid Crystal Research, Jalahalli, Bangalore-560 103 (India)

    2007-10-31

    The investigated optically active dimeric compound, 4-n-undecyloxy-4{sup '}-(cholesteryloxycarbonyl-1-butyloxy)chalcone, shows wide temperature ranges of two twist grain boundary (TGB) phases, TGBA and TGBC*. Comprehensive dielectric studies have been carried out for this compound in the frequency range 1 Hz-10 MHz for different conditions of molecular anchoring. This compound shows negative dielectric anisotropy ({delta}{epsilon}'={epsilon}{sub parallel}'-{epsilon}{sub perpendicul=} a{sub r}'<0). Various electrical parameters, namely the dielectric permittivity, dielectric anisotropy, DC conductivity and activation energy, have been determined for these TGB phases. Weak relaxation processes have been detected in the TGBA and TGBC* phases, presumably due to amplitude (soft mode) and phase (Goldstone mode) fluctuations.

  3. Subzero temperature chromatography for reduced back-exchange and improved dynamic range in amide hydrogen/deuterium exchange mass spectrometry.

    Science.gov (United States)

    Venable, John D; Okach, Linda; Agarwalla, Sanjay; Brock, Ansgar

    2012-11-06

    Amide hydrogen/deuterium exchange is a commonly used technique for studying the dynamics of proteins and their interactions with other proteins or ligands. When coupled with liquid chromatography and mass spectrometry, hydrogen/deuterium exchange provides several unique advantages over other structural characterization techniques including very high sensitivity, the ability to analyze proteins in complex environments, and a large mass range. A fundamental limitation of the technique arises from the loss of the deuterium label (back-exchange) during the course of the analysis. A method to limit loss of the label during the separation stage of the analysis using subzero temperature reversed-phase chromatography is presented. The approach is facilitated by the use of buffer modifiers that prevent freezing. We evaluated ethylene glycol, dimethyl formamide, formamide, and methanol for their freezing point suppression capabilities, effects on peptide retention, and their compatibilities with electrospray ionization. Ethylene glycol was used extensively because of its good electrospray ionization compatibility; however, formamide has potential to be a superior modifier if detrimental effects on ionization can be overcome. It is demonstrated using suitable buffer modifiers that separations can be performed at temperatures as low as -30 °C with negligible loss of the deuterium label, even during long chromatographic separations. The reduction in back-exchange is shown to increase the dynamic range of hydrogen/deuterium exchange mass spectrometry in terms of mixture complexity and the magnitude with which changes in deuteration level can be quantified.

  4. Accurate solid solution range of BiMnxFe3-xO6 and low temperature magnetism

    Science.gov (United States)

    Jiang, Pengfei; Yue, Mufei; Cong, Rihong; Gao, Wenliang; Yang, Tao

    2017-11-01

    BiMnxFe3-xO6 (x = 1) represents a new type of oxide structure containing Bi3+ and competing magnetic super-exchanges. In literature, multiple magnetic states were realized at low temperatures in BiMnFe2O6, and the hypothetical parent compounds (BiMn3O6, BiFe3O6) were predicted to be different in magnetism. Herein, we performed a careful study on the syntheses of BiMnxFe3-xO6 at ambient pressure, and the solid solution range was determined to be 0.9 ≤ x ≤ 1.3 by Rietveld refinements on high-quality powder X-ray diffraction data. Due to the very similar cationic size of Mn3+ and Fe3+, and possibly the structural rigidity, there was no significant structure change in the whole range of solid solution. The magnetic behavior of BiMnxFe3-xO6 (x = 1.2, 1.22, 1.26, 1.28 and 1.3) was generally similar to BiMnFe2O6, while the relative higher concentration of Mn3+ led to the decreasing of the antiferromagnetic ordering temperature.

  5. Performance Demonstration of Mcmb-LiNiCoO2 Cells Containing Electrolytes Designed for Wide Operating Temperature Range

    Science.gov (United States)

    Smart, M. C.; Ratnakumar, B. V.; Whicanack, L. D.; Smith, K. A.; Santee, S.; Puglia, F. J.; Gitzendanner, R.

    2009-01-01

    With the intent of improving the performance of Li-ion cells over a wide operating temperature range, we have investigated the use of co-solvents to improve the properties of electrolyte formulations. In the current study, we have focused upon evaluating promising electrolytes which have been incorporated into large capacity (7 Ah) prototype Li-ion cells, fabricated by Yardney Technical Products, Inc. The electrolytes selected for performance evaluation include the use of a number of esters as co-solvents, including methyl propionate (MP), ethyl propionate (EP), ethyl butyrate (EB), propyl butyrate (PB), and 2,2,2-trifluoroethyl butyrate (TFEB). The performance of the prototype cells containing the ester-based electrolytes was compared with an extensive data base generated on cells containing previously developed all carbonate-based electrolytes. A number of performance tests were performed, including determining (i) the discharge rate capacity over a wide range of temperatures, (ii) the charge characteristics, (iii) the cycle life characteristics under various conditions, and (iv) the impedance characteristics.

  6. Positive or Negative? Urbanization-Induced Variations in Diurnal Skin-Surface Temperature Range Detected Using Satellite Data

    Science.gov (United States)

    Huang, Fan; Zhan, Wenfeng; Wang, Zhihua; Wang, Kaicun; Chen, Jing M.; Liu, Yongxue; Lai, Jiameng; Ju, Weimin

    2017-12-01

    Diurnal temperature range (DTR) is an important indicator for assessing the local climate change due to urbanization. Studies that focused on surface air temperature (SAT) have reported decreased DTRSAT in urban areas. However, this urbanization-induced effect becomes more complex with regard to land skin-surface temperature (LST), which is highly localized and extremely sensitive to land surface properties. We thus investigated the urban-rural DTRLST difference (ΔDTRLST) over 354 cities across China using satellite-retrieved LSTs within 2008-2013. Our major findings include the following: (1) urban areas experience increased (decreased) DTRLST compared with rural areas on the annual average for the majority of cities located in southern (northern) China; (2) the ΔDTRLST is mostly positive in warm months but negative in cold months. It generally becomes more positive from January to August and becomes more negative afterward; and (3) the ΔDTRLST is positively related to the daytime surface urban heat island intensity; it is yet negatively correlated with the urban-rural difference in vegetation abundance. We consider these insights valuable for in-depth understanding urban thermal environment and will likely help improve urban planning.

  7. Sensing mode coupling analysis for dual-mass MEMS gyroscope and bandwidth expansion within wide-temperature range

    Science.gov (United States)

    Cao, Huiliang; Li, Hongsheng; Shao, Xingling; Liu, Zhiyu; Kou, Zhiwei; Shan, Yanhu; Shi, Yunbo; Shen, Chong; Liu, Jun

    2018-01-01

    This paper presents the bandwidth expanding method with wide-temperature range for sense mode coupling dual-mass MEMS gyro. The real sensing mode of the gyroscope is analyzed to be the superposition of in-phase and anti-phase sensing modes. The mechanical sensitivity and bandwidth of the gyroscope structure are conflicted with each other and both governed by the frequency difference between sensing and drive modes (min {Δω1, Δω2}). The sensing mode force rebalancing combs stimulation method (FRCSM) is presented to simulate the Coriolis force, and based on this method, the gyro's dynamic characteristics are tested. The sensing closed- loop controller is achieved by operational amplifier based on phase lead method, which enable the magnitude margin and phase margin of the system to reach 7.21 dB and 34.6° respectively, and the closed-loop system also expands gyro bandwidth from 13 Hz (sensing open-loop) to 102 Hz (sensing closed-loop). What's more, the turntable test results show that the sensing closed-loop works stably in wide-temperature range (from -40 °C to 60 °C) and the bandwidth values are 107 Hz @-40 °C and 97 Hz @60 °C. The results indicate that the higher temperature causes lower bandwidth, and verify the simulation results are 103 Hz @-40 °C and 98.2 Hz @60 °C. The new bottleneck of the closed loop bandwidth is the valley generated by conjugate zeros, which is formed by superposition of sensing modes.

  8. Molecular Dynamics Simulation Study of Skin Lipids: Effects of the Molar Ratio of Individual Components over a Wide Temperature Range.

    Science.gov (United States)

    Gupta, Rakesh; Rai, Beena

    2015-09-03

    Atomistic molecular dynamics (MD) simulations were employed to systematically investigate the effects of the molar ratio of the individual components cholesterol (CHOL), free fatty acid (FFA), and ceramides (CER) on the properties of the skin lipid bilayer over a wide temperature range (300-400 K). Several independent simulations were performed for bilayers comprised of only CER, CHOL, or FFA molecules as well as those made up of a mixture of CER:CHOL:FFA molecules in different molar ratios. It was found that CHOL increases the stability of the bilayer, since the mixed (CER:CHOL:FFA) 1:1:0, 1:1:1, and 2:2:1 bilayers remained stable until 400 K while the pure ceramide bilayer disintegrated around ∼390 K. It was also observed that CHOL reduces the volume spanned by ceramide molecules, thereby leading to a higher area per CER and FFA molecule in the mixed bilayer system. The CHOL molecule provided more rigidity to the mixed bilayer and led to a more ordered phase at elevated temperatures. The CHOL molecule provided fluidity to the bilayer below the phase transition temperature of CER and kept the bilayer rigid above the phase transition temperature. The FFA interdigitizes with CER molecules and increases the thickness of the bilayer, while rigid CHOL decreases the bilayer thickness. The presence of CHOL increases the compressibility of the bilayer which is responsible for the high barrier function of skin. The CER molecule forms inter- and intramolecular hydrogen bonds, while CHOL only forms intermolecular hydrogen bonds.

  9. Autumn-winter minimum temperature changes in the southern Sikhote-Alin mountain range of northeastern Asia since 1529 AD

    Science.gov (United States)

    Ukhvatkina, Olga N.; Omelko, Alexander M.; Zhmerenetsky, Alexander A.; Petrenko, Tatyana Y.

    2018-01-01

    The aim of our research was to reconstruct climatic parameters (for the first time for the Sikhote-Alin mountain range) and to compare them with global climate fluctuations. As a result, we have found that one of the most important limiting factors for the study area is the minimum temperatures of the previous autumn-winter season (August-December), and this finding perfectly conforms to that in other territories. We reconstructed the previous August-December minimum temperature for 485 years, from 1529 to 2014. We found 12 cold periods (1535-1540, 1550-1555, 1643-1649, 1659-1667, 1675-1689, 1722-1735, 1791-1803, 1807-1818, 1822-1827, 1836-1852, 1868-1887, 1911-1925) and seven warm periods (1560-1585, 1600-1610, 1614-1618, 1738-1743, 1756-1759, 1776-1781, 1944-2014). These periods correlate well with reconstructed data for the Northern Hemisphere and the neighboring territories of China and Japan. Our reconstruction has 3-, 9-, 20-, and 200-year periods, which may be in line with high-frequency fluctuations in El Niño-Southern Oscillation (ENSO), the short-term solar cycle, Pacific Decadal Oscillation (PDO) fluctuations, and the 200-year solar activity cycle, respectively. We suppose that the temperature of the North Pacific, expressed by the PDO may make a major contribution to regional climate variations. We also assume that the regional climatic response to solar activity becomes apparent in the temperature changes in the northern part of Pacific Ocean and corresponds to cold periods during the solar minimum. These comparisons show that our climatic reconstruction based on tree ring chronology for this area may potentially provide a proxy record for long-term, large-scale past temperature patterns for northeastern Asia. The reconstruction reflects the global traits and local variations in the climatic processes of the southern territory of the Russian Far East for more than the past 450 years.

  10. A performance analysis of echographic ultrasonic techniques for non-invasive temperature estimation in hyperthermia range using phantoms with scatterers.

    Science.gov (United States)

    Bazán, I; Vazquez, M; Ramos, A; Vera, A; Leija, L

    2009-03-01

    Optimization of efficiency in hyperthermia requires a precise and non-invasive estimation of internal distribution of temperature. Although there are several research trends for ultrasonic temperature estimation, efficient equipments for its use in the clinical practice are not still available. The main objective of this work was to research about the limitations and potential improvements of previously reported signal processing options in order to identify research efforts to facilitate their future clinical use as a thermal estimator. In this document, we have a critical analysis of potential performance of previous ultrasonic research trends for temperature estimation inside materials, using different processing techniques proposed in frequency, time and phase domains. It was carried out in phantom with scatterers, assessing at their specific applicability, linearity and limitations in hyperthermia range. Three complementary evaluation indexes: technique robustness, Mat-lab processing time and temperature resolution, with specific application protocols, were defined and employed for a comparative quantification of the behavior of the techniques. The average increment per degrees C and mm was identified for each technique (3 KHz/ degrees C in the frequency analysis, 0.02 rad/ degrees C in the phase domain, while increments in the time domain of only 1.6 ns/ degrees C were found). Their linearity with temperature rising was measured using linear and quadratic regressions and they were correlated with the obtained data. New improvements in time and frequency signal processing in order to reveal the potential thermal and spatial resolutions of these techniques are proposed and their subsequent improved estimation results are shown for simulated and measured A-scans registers. As an example of these processing novelties, an excellent potential resolution of 0.12 degrees C into hyperthermia range, with near-to-linear frequency dependence, could be achieved

  11. Impact of diurnal temperature range on mortality in a high plateau area in southwest China: A time series analysis.

    Science.gov (United States)

    Ding, Zan; Guo, Pi; Xie, Fang; Chu, Huifang; Li, Kun; Pu, Jingbo; Pang, Shaojie; Dong, Hongli; Liu, Yahui; Pi, Fuhua; Zhang, Qingying

    2015-09-01

    Diurnal temperature range (DTR) is an important meteorological indicator that reflects weather stability and is associated with global climate change and urbanization. Previous studies have explored the effect of DTR on human health in coastal cities with small daily temperature variations, but we have little evidence for high plateau regions where large DTRs usually occur. Using daily mortality data (2007-2013), we conducted a time-series analysis to assess the effect of DTR on daily mortality in Yuxi, a high plateau city in southwest China. Poisson regression with distributed lag non-linear model was used to estimate DTR effects on daily mortality, controlling for daily mean temperature, relative humidity, sunshine duration, wind speed, atmospheric pressure, day of the week, and seasonal and long-term trends. The cumulative effects of DTR were J-shaped curves for non-accidental, cardiorespiratory and cardiovascular mortality, with a U-shaped curve for respiratory mortality. Risk assessments showed strong monotonic increases in mortality starting at a DTR of approximately 16 °C. The relative risk of non-accidental morality with extreme high DTR at lag 0 and 0-21 days was 1.03 (95% confidence interval: 0.95-1.11) and 1.33 (0.94-1.89), respectively. The risk of mortality with extreme high DTR was greater for males and age <75 years than females and age ≥75 years. The effect of DTR on mortality was non-linear, with high DTR associated with increased mortality. A DTR of 16 °C may be a cut-off point for mortality prognosis and has implications for developing intervention strategies to address high DTR exposure. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Impact of vegetation removal and soil aridation on diurnal temperature range in a semiarid region: application to the Sahel.

    Science.gov (United States)

    Zhou, Liming; Dickinson, Robert E; Tian, Yuhong; Vose, Russell S; Dai, Yongjiu

    2007-11-13

    Increased clouds and precipitation normally decrease the diurnal temperature range (DTR) and thus have commonly been offered as explanation for the trend of reduced DTR observed for many land areas over the last several decades. Observations show, however, that the DTR was reduced most in dry regions and especially in the West African Sahel during a period of unprecedented drought. Furthermore, the negative trend of DTR in the Sahel appears to have stopped and may have reversed after the rainfall began to recover. This study develops a hypothesis with climate model sensitivity studies showing that either a reduction in vegetation cover or a reduction in soil emissivity would reduce the DTR by increasing nighttime temperature through increased soil heating and reduced outgoing longwave radiation. Consistent with empirical analyses of observational data, our results suggest that vegetation removal and soil aridation would act to reduce the DTR during periods of drought and human mismanagement over semiarid regions such as the Sahel and to increase the DTR with more rainfall and better human management. Other mechanisms with similar effects on surface energy balance, such as increased nighttime downward longwave radiation due to increased greenhouse gases, aerosols, and clouds, would also be expected to have a larger impact on DTR over drier regions.

  13. Fluoride salts and container materials for thermal energy storage applications in the temperature range 973 - 1400 K

    Science.gov (United States)

    Misra, Ajay K.; Whittenberger, J. Daniel

    1987-01-01

    Multicomponent fluoride salt mixtures were characterized for use as latent heat of fusion heat storage materials in advanced solar dynamic space power systems with operating temperatures in the range of 973 to 1400 K. The melting points and eutectic composition for many systems with published phase diagrams were verified, and several new eutectic compositions were identified. Additionally, the heats of fusion of several binary and ternary eutectics and congruently melting intermediate compounds were measured by differential scanning calorimetry. The extent of corrosion of various metals by fluoride melts was estimated from thermodynamic considerations, and equilibrium conditions inside a containment vessel were calculated as functions of the initial moisture content of the salt and free volume above the molten salt. Preliminary experimental data on the corrosion of commercial, high-temperature alloys in LiF-19.5CaF2 and NaF-27CaF2-36MgF2 melts are presented and compared to the thermodynamic predictions.

  14. Fluoride salts and container materials for thermal energy storage applications in the temperature range 973 to 1400 K

    Science.gov (United States)

    Misra, Ajay K.; Whittenberger, J. Daniel

    1987-01-01

    Multicomponent fluoride salt mixtures were characterized for use as latent heat of fusion heat storage materials in advanced solar dynamic space power systems with operating temperatures in the range of 973 to 1400 K. The melting points and eutectic composition for many systems with published phase diagrams were verified, and several new eutectic compositions were identified. Additionally, the heats of fusion of several binary and ternary eutectics and congruently melting intermediate compounds were measured by differential scanning calorimetry. The extent of corrosion of various metals by fluoride melts was estimated from thermodynamic considerations, and equilibrium conditions inside a containment vessel were calculated as functions of the initial moisture content of the salt and free volume above the molten salt. Preliminary experimental data on the corrosion of commercial, high-temperature alloys in LiF-19.5CaF2 and NaF-27CaF2-36MgF2 melts are presented and compared to the thermodynamic predictions.

  15. The ageing kinetics of CF3 cast stainless steel in the temperature range 3000C to 400OC

    International Nuclear Information System (INIS)

    Akhurst, K.N.; Pumphrey, P.H.

    1988-11-01

    The primary coolant pump casings for Sizewell 'B' are made from castings of ASME SA351 CF3 steel which, although predominantly austenitic, is required to contain a small proportion of ferrite. Previous studies have shown that such steels are susceptible to hardening of the ferrite, and associated losses in toughness, as a result of thermal ageing for long times at the service temperature (∼ 300 0 C). For this reason, toughness tests are to be carried out on representative castings made by the Sizewell 'B' pump casing manufacturer. The purpose of these tests is to demonstrate adequate end-of-life fracture resistance, using material which has been given an accelerated ageing treatment. The identification and validation of a suitable ageing treatment is the subject of this Report. Ageing kinetics have been measured for ageing temperatures in the range 300 to 400 0 C, from the results of Charpy impact tests on material from the castings procured for the main fracture programme. Castings with ferrite levels of 15, 25 and 35% have been studied. The losses in impact toughness have been related to the kinetics of ferrite strengthening using microhardness measurements, and to microstructural changes using Field Ion Atom Probe analysis. (author)

  16. Topography, structure, and formation kinetic mechanism of carbon deposited onto nickel in the temperature range from 400 to 850°C

    Science.gov (United States)

    Chen, Zhi-yuan; Bian, Liu-zhen; Wang, Li-jun; Yu, Zi-you; Zhao, Hai-lei; Li, Fu-shen; Chou, Kuo-chih

    2017-05-01

    The carbon deposition behavior on nickel particles was observed within the temperature range from 400 to 800°C in a pure methane atmosphere. The topography, properties, and molecular structure of the deposited carbon were investigated using field-emission scanning electron microscopy (FESEM), temperature-programmed oxidation (TPO) technology, X-ray diffraction (XRD), and Raman spectroscopy. The deposited carbon is present in the form of a film at 400-450°C, as fibers at 500-600°C, and as particles at 650-800°C. In addition, the structure of the deposited carbon becomes more ordered at higher temperatures because both the TPO peak temperature of deposited carbon and the Raman shift of the G band increase with the increase in experimental temperature, whereas the intensity ratio between the D bands and the G band decreases. An interesting observation is that the carbon deposition rate is suppressed in the medium-temperature range (M-T range) and the corresponding kinetic mechanism changes. Correspondingly, the FWHM of the G and D1 bands in the Raman spectrum reaches a maximum and the intensities of the D2, D3, and D4 bands decrease to low limits in the M-T range. These results indicate that carbon structure parameters exhibit two different tendencies with respect to varying temperature. Both of the two group parameters change dramatically as a peak function with increasing reaction temperature within the M-T range.

  17. Development of Superior Sorbents for Separation of CO2 from Flue Gas at a Wide Temperature Range During Coal Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Panagiotis G. Smirniotis

    2007-06-30

    In chapter 1, the studies focused on the development of novel sorbents for reducing the carbon dioxide emissions at high temperatures. Our studies focused on cesium doped CaO sorbents with respect to other major flue gas compounds in a wide temperature range. The thermo-gravimetric analysis of sorbents with loadings of CaO doped on 20 wt% cesium demonstrated high CO{sub 2} sorption uptakes (up to 66 wt% CO{sub 2}/sorbent). It is remarkable to note that zero adsorption affinity for N{sub 2}, O{sub 2}, H{sub 2}O and NO at temperatures as high as 600 C was observed. For water vapor and nitrogen oxide we observed a positive effect for CO{sub 2} adsorption. In the presence of steam, the CO{sub 2} adsorption increased to the highest adsorption capacity of 77 wt% CO{sub 2}/sorbent. In the presence of nitrogen oxide, the final CO{sub 2} uptake remained same, but the rate of adsorption was higher at the initial stages (10%) than the case where no nitrogen oxide was fed. In chapter 2, Ca(NO{sub 3}){sub 2} {center_dot} 4H{sub 2}O, CaO, Ca(OH){sub 2}, CaCO{sub 3}, and Ca(CH{sub 3}COO){sub 2} {center_dot} H{sub 2}O were used as precursors for synthesis of CaO sorbents on this work. The sorbents prepared from calcium acetate (CaAc{sub 2}-CaO) resulted in the best uptake characteristics for CO{sub 2}. It possessed higher BET surface area and higher pore volume than the other sorbents. According to SEM images, this sorbent shows 'fluffy' structure, which probably contributes to its high surface area and pore volume. When temperatures were between 550 and 800 C, this sorbent could be carbonated almost completely. Moreover, the carbonation progressed dominantly at the initial short period. Under numerous adsorption-desorption cycles, the CaAc{sub 2}-CaO demonstrated the best reversibility, even under the existence of 10 vol % water vapor. In a 27 cyclic running, the sorbent sustained fairly high carbonation conversion of 62%. Pore size distributions indicate that their

  18. Radiation-Hardening of Best-In-Class SiGe Mixed-Signal and RF Electronics for Ultra-Wide Temperature Range, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Innovative, reliable, low-power, and low-noise electronics that can operate over a wide temperature range and high radiation are critical for future NASA missions....

  19. Radiation-Hardening of Best-in-Class SiGe Mixed-Signal and RF Electronics for Ultra-Wide Temperature Range, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Innovative, reliable, low-power, and low-noise electronics that can operate over a wide temperature range and high radiation are critical for future NASA missions....

  20. High Damping of Lightweight TiNi-Ti2Ni Shape Memory Composites for Wide Temperature Range Usage

    Science.gov (United States)

    Yang, Bing; Luo, Zheng; Yuan, Bin; Liu, Jiangwen; Gao, Yan

    2017-10-01

    A bimodal porous TiNi-Ti2Ni shape memory alloy composite (SMAC) with 59% porosity was fabricated by sintering Ti-46at.%Ni elemental powders with pore-forming agent. The porous TiNi-Ti2Ni SMAC contains two irregular pores of about 400 and 120 μm. We investigated the microstructure and pore morphology correlated with the mechanical properties and damping capacities of the SMAC. Ti2Ni intermetallic phases with size of 1-3 μm were homogeneously distributed in the TiNi matrix. The porous TiNi-Ti2Ni SMAC exhibits exceptionally high inverse mechanical quality factor ( Q -1) of 0.25 at SMAC at relatively low strain amplitude can exhibit considerable high Q -1 of 0.06 0.11 for a wide range of temperature between - 90 and 200 °C, which is attributed to the stress concentration distribution provided by the bimodal structure of pores and the massive interfaces between pore/matrix and TiNi/Ti2Ni. These porous SMACs can be an ideal candidate for using as a lightweight damping material in the energy-saving applications.

  1. X-ray diffraction study of the fine structure of twaron fibres in the temperature range 750 kelvin - 9500 kelvin

    International Nuclear Information System (INIS)

    Abu Obaid, A. A.

    1991-01-01

    The thesis dealt with the fine structural behaviour of twaron fibres, spun from the polymer poly (p-phenylene terephthalamide), due to physical treatments in the temperature range 75 to 984 kelvin (-198 to 675 degrees celsius). The treatments were annealing, cooling, cold ageing and vibratory milling. The structure was characterized by wide-angle x-ray diffraction (WAXS) and thermogravimetric analysis (TGA). The structural parameters included crystallinity, microparacrystal (mPc) sizes, net plane spacings, unit cell dimensions and mass stability. The TGA results indicated good mass stability up to 500 degrees celsius. The crystallinity and mPc sizes reached their maximum values after annealing the fibres at 425 degrees celsius (crystallinity increased by 5% and mPC sizes increased by approximately 40 to 50 %). After 500 degrees celsius, the crystallinity and mPC sizes dropped remarkably. Cooling the twaron fibres down to -198 degrees celsius did not affect the structure. Cold ageing of the fibres at -15 degrees celsius for periods up to 100 days, and cold ageing at -198 degrees celsius up to 48 hours did not affect the structure as well; however cold ageing at -198 degrees celsius for 120 hours caused a drop of 5% in the crystallinity and 10% in the mPc sizes. 35 refs., 28 figs., 9 tabs. (A.M.H.)

  2. Kinetics of the gas-phase reaction between hydroxyl and carbonyl sulfide over the temperature range 300-517 K

    Science.gov (United States)

    Leu, M.-T.; Smith, R. H.

    1981-01-01

    By use of a discharge-flow resonance-fluorescence method the rate constant for the title reaction has been measured at five temperatures in the range 300-520 K. The Arrhenius expression is k(OH + OCS) = (1.3 + or - 0.3) x 10 to the -12th exp/-(2300 + or - 100)/T/ cu cm/s. Mass spectrometry has been used to detect the product HS and to collect some information about its reactivity. This study has carefully avoided the pitfalls associated with possible photolysis of reactants and complications due to H2S impurity in carbonyl sulfide that may have marred previous studies. This study has confirmed that the rate constant for this reaction is so much lower than the value originally used in computer modeling of the upper and lower atmosphere that conclusions about the relative importance of photolysis of OCS and of the reaction OH + OCS in the stratosphere must now be reassessed. The reaction OH + OCS has little significance for atmospheric chemistry.

  3. Higher Storage Temperature Causes Greater Salmonella enterica Serovar Typhimurium Internal Penetration of Artificially Contaminated, Commercially Available, Washed Free Range Eggs.

    Science.gov (United States)

    Whiley, Alice; Fallowfield, Howard; Ross, Kirstin; McEvoy, Vanessa; Whiley, Harriet

    2016-07-01

    Foodborne salmonellosis is a major public health concern, with contaminated eggs identified as a significant source of infection. In Australia, the most prevalent cause of salmonellosis from eggs is Salmonella enterica subsp. enterica serovar Typhimurium. This study explored the effect of temperature after 1, 7, 14, 21, and 28 days of storage on commercially available washed free range eggs, artificially contaminated with Salmonella Typhimurium on the external surface. At each time point, the external surface of the egg, the crushed eggshell, and the internal egg yolk and albumen were analyzed for Salmonella. After 28 days of storage, 25% of eggs stored at 4°C, 50% of eggs stored at 14°C, and 100% of eggs stored at 23 and 35°C were internally contaminated with Salmonella. After 1 day of storage, more than 50% of all eggs had Salmonella present in the crushed shell after the external surface had been disinfected with ethanol. This is the first study to demonstrate that refrigeration reduced the potential for Salmonella Typhimurium to penetrate the eggshell membrane and internally contaminate table eggs commercially available in Australia. It also suggests that the processes of cracking eggs may be a source of cross-contamination within the kitchen.

  4. Large Magnetocaloric Effect Around Room Temperature in Amorphous Fe-Gd-Zr Alloy Ribbon with Short-Range Interactions

    Science.gov (United States)

    Thanh, Tran Dang; Yen, Nguyen Hai; Duc, Nguyen Huu; Phan, The-Long; Dan, Nguyen Huy; Yu, Seong-Cho

    2016-05-01

    In this work, we present a detailed study on the magnetocaloric effect and the critical behaviors of an amorphous Fe88Gd2Zr10 alloy ribbon prepared by using a rapid quenching method. We point out that the value of maximum magnetic entropy change (|Δ S max|) of amorphous Fe88Gd2Zr10 alloy ribbon appeared at near room temperature and versus Δ H obeys a power law, |Δ S max| = a·Δ H n. In addition, all Δ S m( T, Δ H) data measured at different Δ H values are collapsed onto a universal master curve. Interestingly, M 2 versus H/ M curves prove amorphous Fe88Gd2Zr10 ribbon exhibitied a second-order magnetic phase transition. The critical exponents ( β, γ, and δ) obtained from the modified Arrott plots and the Kouvel-Fisher methods, and critical isotherm analysis are very close to those expected for the 3D-Heisenberg model, proving ferromagnetic short-range interactions exist in amorphous Fe88Gd2Zr10 ribbon.

  5. Variability and trend of diurnal temperature range in China and their relationship to total cloud cover and sunshine duration

    Science.gov (United States)

    Xia, X.

    2013-05-01

    This study aims to investigate the effect of total cloud cover (TCC) and sunshine duration (SSD) in the variation of diurnal temperature range (DTR) in China during 1954-2009. As expected, the inter-annual variation of DTR was mainly determined by TCC. Analysis of trends of 30-year moving windows of DTR and TCC time series showed that TCC changes could account for that of DTR in some cases. However, TCC decreased during 1954-2009, which did not support DTR reduction across China. DTRs under sky conditions such as clear, cloudy and overcast showed nearly the same decreasing rate that completely accounted for the overall DTR reduction. Nevertheless, correlation between SSD and DTR was weak and not significant under clear sky conditions in which aerosol direct radiative effect should be dominant. Furthermore, 30-60% of DTR reduction was associated with DTR decrease under overcast conditions in south China. This implies that aerosol direct radiative effect appears not to be one of the main factors determining long-term changes in DTR in China.

  6. Fluoride salts as phase change materials for thermal energy storage in the temperature range 1000-1400 K

    Science.gov (United States)

    Misra, Ajay K.

    1988-01-01

    Eutectic compositions and congruently melting intermediate compounds in binary and ternary fluoride salt systems were characterized for potential use as latent heat of fusion phase change materials to store thermal energy in the temperature range 1000-1400 K. The melting points and eutectic compositions for many systems with published phase diagrams were experimentally verified and new eutectic compositions having melting points between 1000 and 1400 K were identified. Heats of fusion of several binary and ternary eutectics and congruently melting compounds were experimentally measured by differential scanning calorimetry. For a few systems in which heats of mixing in the melts have been measured, heats of fusion of the eutectics were calculated from thermodynamic considerations and good agreement was obtained between the measured and calculated values. Several combinations of salts with high heats of fusion per unit mass (greater than 0.7 kJ/g) have been identified for possible use as phase change materials in advanced solar dynamic space power applications.

  7. Access to warm drinking water prevents rumen temperature drop without affecting in situ NDF disappearance in grazing winter range cows

    Science.gov (United States)

    Ingestion of large quantities of cold water or frozen forage may result in changes in temperature of ruminal contents. Rumen microorganisms may be sensitive to temperature changes in the ruminal environment. Therefore, this study was conducted to assess the variability in ruminal temperature and e...

  8. Long-lived Control of Sierras Pampeanas Ranges on Andean Foreland Basin Evolution Revealed by Coupled Low-temperature Thermochronology and Sedimentology

    Science.gov (United States)

    Stevens Goddard, A.; Carrapa, B.; Larrovere, M.; Aciar, R. H.

    2017-12-01

    The Sierras Pampeanas ranges of west-central Argentina (28º- 31ºS) are a classic example of thick-skinned style basement block uplifts. The style and timing of uplift in these mountain ranges has widely been attributed to the onset of flat-slab subduction in the middle to late Miocene. However, the majority of low-temperature thermochronometers in the Sierras Pampeanas have much older cooling dates. Thermal modeling derived from new low-temperature thermochronometers in Sierra de Velasco, one of the highest relief (> 4 km) mountains in the Sierras Pampeanas, suggest that the rocks in these ranges have been at near-surface temperatures (history of long-lived topography illustrated in Sierra de Velasco can be expanded to other ranges in the Sierras Pampeanas by integrating multiple data sets.

  9. A Combined State of Charge Estimation Method for Lithium-Ion Batteries Used in a Wide Ambient Temperature Range

    Directory of Open Access Journals (Sweden)

    Fei Feng

    2014-05-01

    Full Text Available Ambient temperature is a significant factor that influences the characteristics of lithium-ion batteries, which can produce adverse effects on state of charge (SOC estimation. In this paper, an integrated SOC algorithm that combines an advanced ampere-hour counting (Adv Ah method and multistate open-circuit voltage (multi OCV method, denoted as “Adv Ah + multi OCV”, is proposed. Ah counting is a simple and general method for estimating SOC. However, the available capacity and coulombic efficiency in this method are influenced by the operating states of batteries, such as temperature and current, thereby causing SOC estimation errors. To address this problem, an enhanced Ah counting method that can alter the available capacity and coulombic efficiency according to temperature is proposed during the SOC calculation. Moreover, the battery SOCs between different temperatures can be mutually converted in accordance with the capacity loss. To compensate for the accumulating errors in Ah counting caused by the low precision of current sensors and lack of accurate initial SOC, the OCV method is used for calibration and as a complement. Given the variation of available capacities at different temperatures, rated/non-rated OCV–SOCs are established to estimate the initial SOCs in accordance with the Ah counting SOCs. Two dynamic tests, namely, constant- and alternated-temperature tests, are employed to verify the combined method at different temperatures. The results indicate that our method can provide effective and accurate SOC estimation at different ambient temperatures.

  10. Applications of the KKR-DCA: A Finite-Temperature Density Functional Theory to Predict Chemical Short-Range Order Effects in Disordered Metallic Alloys

    Science.gov (United States)

    Biava, D. A.; Johnson, D. D.

    2009-03-01

    Short-range order (SRO) is ubiquitous in metallic alloys, affecting changes in their electronic, thermodynamic, mechanical, magnetic, and structural properties. For example, SRO is responsible for the yield-strength anomalies observed in Cu-Al at high temperatures, i.e., the materials is more resistant to dislocation motion at high temperature than it is at room temperature. Within the Korringa-Kohn-Rostorker (KKR) electronic-structure method, we present results using the dynamical cluster approximations (DCA) to obtain the temperature-dependent SRO in disordered alloys. We obtain the KKR-DCA SRO energetics versus local neighbor SRO parameters and minimize it at fixed temperature to predict the SRO. We show that the calculated SRO at fixed temperature compares well with available experimental results, and then correlate the results to the electronic structure. We discuss how an accurate analytic estimate can be made for the SRO in most metals due to the dependence of the grand potential on SRO.

  11. Detection of irradiated foods by the thermoluminescence. Relationships between the temperature ranges of integrating TL glow curves and TL glow ratios

    International Nuclear Information System (INIS)

    Sekiguchi, Masayuki; Yamazaki, Masao; Goto, Michiko; Todoriki, Setsuko; Hagiwara, Shoji

    2007-01-01

    Our study demonstrated that the effects of the several temperature ranges for integrating TL glow intensity on the TL glow ratios by using spice-set purchased at a Turkish air port. The spice set had no labeling of irradiation feeds, but nine of 12 spices were judged as irradiated food in this study. Those temperature ranges were defined by evaluating the glow curves of irradiated TLD-100 chip (167-230degC), TLD-100 disc (177-238degC) and Dolomite element (145-258degC). Those are relatively stable and the difference of typical glow peak temperatures of TLD-100 disc in two institutes was less than 2%. On the other hand, those of TLD-100 tip was shift to higher temperature side at about 4degC because of declining of thermal conductance. The temperature ranges defined by TLD-100 were showed that discriminate more clearly between irradiated and nonirradiated spices compared with the full temperature range of TL measurement (70-400degC). With the exception of low glow intensity, background measurement for estimating net glow intensity was not necessary because TL glow ratio was hardly influenced whether the background measured or not. (author)

  12. Effect of daily temperature range on respiratory health in Argentina and its modification by impaired socio-economic conditions and PM10 exposures

    International Nuclear Information System (INIS)

    Carreras, Hebe; Zanobetti, Antonella; Koutrakis, Petros

    2015-01-01

    Epidemiological investigations regarding temperature influence on human health have focused on mortality rather than morbidity. In addition, most information comes from developed countries despite the increasing evidence that climate change will have devastating impacts on disadvantaged populations living in developing countries. In the present study, we assessed the impact of daily temperature range on upper and lower respiratory infections in Cordoba, Argentina, and explored the effect modification of socio-economic factors and influence of airborne particles We found that temperature range is a strong risk factor for admissions due to both upper and lower respiratory infections, particularly in elderly individuals, and that these effects are more pronounced in sub-populations with low education level or in poor living conditions. These results indicate that socio-economic factors are strong modifiers of the association between temperature variability and respiratory morbidity, thus they should be considered in risk assessments. - Highlights: • Daily temperature range is a strong risk factor for respiratory infections. • Low education level and poor living conditions are strong modifiers of this relationship. • In Cordoba city higher risk for respiratory infections were observed during summertime. - Daily temperature range is a strong risk factor for respiratory infections, particularly for populations with low educational level or poor living conditions.

  13. A low-power tool for measuring acceleration, pressure, and temperature (APT) with wide dynamic range and bandwidth

    Science.gov (United States)

    Heesemann, Martin; Davis, Earl E.; Paros, Jerome; Johnson, Greg; Meldrum, Robert; Scherwath, Martin; Mihaly, Steven

    2017-04-01

    We present a new tool that facilitates the study of inter-related geodetic, geodynamic, seismic, and oceanographic phenomena. It incorporates a temperature compensated tri-axial accelerometer developed by Quartz Seismic Sensors, Inc., a pressure sensor built by Paroscientific Inc., and a low-power, high-precision frequency counter developed by Bennest Enterprises Ltd. and built by RBR, Ltd. The sensors are housed in a 7 cm o.d. titanium pressure case designed for use to full ocean depths (withstands more than 20 km of water pressure). Sampling intervals are programmable from 0.08 s to 1 hr; standard memory can store up to 130 million samples; total power consumption is roughly 115 mW when operating continuously and proportionately lower when operating intermittently (e.g., 2 mW average at 1 sample per min). Serial and USB communications protocols allow a variety of autonomous and cable-connection options. Measurement precision of the order of 10-8 of full scale (e.g., pressure equivalent to 4000 m water depth, acceleration = +/- 3 g) allows observations of pressure and acceleration variations of 0.4 Pa and 0.3 μm s-2. Long-term variations in vertical acceleration are sensitive to displacement through the gravity gradient down to a level of roughly 2 cm, and variations in horizontal acceleration are sensitive to tilt down to a level of 0.03 μrad. With the large dynamic ranges, high sensitivities and broad bandwidth (6 Hz to DC), ground motion associated with microseisms, strong and weak seismic ground motion, tidal loading, and slow and rapid geodynamic deformation - all normally studied using disparate instruments - can be observed with a single tool. Installation in the marine environment is accomplished by pushing the tool roughly 1 m vertically below the seafloor with a submersible or remotely operated vehicle, with no profile remaining above the seafloor to cause current-induced noise. The weight of the tool is designed to match the sediment it displaces to

  14. The enhanced range of temperature for coefficient of low thermal expansion, electrical and thermal conductivities of Cu substituted Fe-Ni invar alloys

    Science.gov (United States)

    Khan, S. A.; Ziya, A. B.; Ibrahim, A.; Atiq, S.; Ahmad, N.; Bashir, F.

    2016-03-01

    Six alloys of Fe65Ni35-x Cu x (x = 0, 0.2, 0.6, 1, 1.4, 1.8 at.%) have been prepared by conventional arc-melting technique and characterized by utilizing high temperature x-ray diffraction (HTXRD) technique at a range from room temperature to 773 K for determination of phase, lattice parameter (a), coefficient of thermal expansion (α(T)), mean square amplitude of vibration (\\bar{{u}2}), characteristic Debye temperature (ΘD), electrical resistivity (ρ) and thermal conductivity (κ). The studies showed that these alloys form face centered cubic structure (fcc) throughout the investigated temperature range. The values of α(T) were found to be comparable to those for conventional Fe-Ni invar alloys but have increased temperature span to a significant extent. The mean square amplitude of vibration (\\bar{{u}2}) and Debye temperature were found to remain almost unchanged in the invar temperature range, whereas the electrical and thermal conductivity were found to improve.

  15. Irradiation Creep of Ferritic-Martensitic Steels EP-450, EP-823 and EI-852 Irradiated in the BN-350 Reactor over Wide Ranges of Irradiation Temperature and Dose

    International Nuclear Information System (INIS)

    Porollo, S.I.; Konobeev, Y.V.; Ivanov, A.A.; Shulepin, S.V.; Garner, F.

    2007-01-01

    Full text of publication follows: Ferritic/martensitic (F/M) steels appear to be the most promising materials for advanced nuclear systems, especially for fusion reactors. Their main advantages are higher resistance to swelling and lower irradiation creep rate as has been repeatedly demonstrated in examinations of these materials after irradiation. Nevertheless, available experimental data on irradiation resistance of F/M steels are insufficient, with the greatest deficiency of data for high doses and for both low and high irradiation temperatures. From the very beginning of operation the BN-350 fast reactor has been used for irradiation of specimens of structural materials, including F/M steels. The most unique feature of BN-350 was its low inlet sodium temperature, allowing irradiation at temperatures over a very wide range of temperatures compared with the range in other fast reactors. In this paper data are presented on swelling and irradiation creep of three Russian F/M steels EP-450, EP-823 and EI-852, irradiated in experimental assemblies of the BN-350 reactor at temperatures in the range of 305-700 deg. C to doses ranging from 20 to 89 dpa. The investigation was performed using gas-pressurized creep tubes with hoop stresses in the range of 0 - 294 MPa. (authors)

  16. Calculation of Distribution Dynamics of Inhomogeneous Temperature Field in Range of Fuel Elements by Using FreeFem++

    Science.gov (United States)

    Amosova, E. V.; Shishkin, A. V.

    2017-11-01

    This article introduces the result of studying the heat exchange in the fuel element of the nuclear reactor fuel magazine. Fuel assemblies are completed as a bundle of cylindrical fuel elements located at the tops of a regular triangle. Uneven distribution of fuel rods in a nuclear reactor’s core forms the inhomogeneity of temperature fields. This article describes the developed method for heat exchange calculation with the account for impact of an inhomogeneous temperature field on the thermal-physical properties of materials and unsteady effects. The acquired calculation results are used for evaluating the tolerable temperature levels in protective case materials.

  17. Radiometric measurements of wall temperatures in the 800 K to 1150 K range for a quartz radiant heating tube

    International Nuclear Information System (INIS)

    Blevins, L.G.; Sivathanu, Y.R.; Gore, J.P.; Shahien, M.A.

    1995-01-01

    Many industrial applications require heat transfer to a load in an inert environment, which can be achieved by using gas-fired radiant tubes. A radiant tube consists of a flame confined in a cylindrical metal or ceramic chamber. The flame heats the tube wall, which in turn radiates to the load. One important characteristic of radiant heating tubes is wall temperature uniformity. Numerical models of radiant tubes have been used to predict wall temperatures, but there is a lack of experimental data for validation. Recently, Namazian et al., Singh and Gorski, and Peters et al. have measured wall temperature profiles of radiant tubes using thermocouples. 13 refs., 3 figs

  18. Determination of Germination Response to Temperature and Water Potential for a Wide Range of Cover Crop Species and Related Functional Groups.

    Science.gov (United States)

    Tribouillois, Hélène; Dürr, Carolyne; Demilly, Didier; Wagner, Marie-Hélène; Justes, Eric

    2016-01-01

    A wide range of species can be sown as cover crops during fallow periods to provide various ecosystem services. Plant establishment is a key stage, especially when sowing occurs in summer with high soil temperatures and low water availability. The aim of this study was to determine the response of germination to temperature and water potential for diverse cover crop species. Based on these characteristics, we developed contrasting functional groups that group species with the same germination ability, which may be useful to adapt species choice to climatic sowing conditions. Germination of 36 different species from six botanical families was measured in the laboratory at eight temperatures ranging from 4.5-43°C and at four water potentials. Final germination percentages, germination rate, cardinal temperatures, base temperature and base water potential were calculated for each species. Optimal temperatures varied from 21.3-37.2°C, maximum temperatures at which the species could germinate varied from 27.7-43.0°C and base water potentials varied from -0.1 to -2.6 MPa. Most cover crops were adapted to summer sowing with a relatively high mean optimal temperature for germination, but some Fabaceae species were more sensitive to high temperatures. Species mainly from Poaceae and Brassicaceae were the most resistant to water deficit and germinated under a low base water potential. Species were classified, independent of family, according to their ability to germinate under a range of temperatures and according to their base water potential in order to group species by functional germination groups. These groups may help in choosing the most adapted cover crop species to sow based on climatic conditions in order to favor plant establishment and the services provided by cover crops during fallow periods. Our data can also be useful as germination parameters in crop models to simulate the emergence of cover crops under different pedoclimatic conditions and crop

  19. Thermal sensation and the skin sensation test: regional differences and their effects on the issue of reliability of temperature ranges.

    Science.gov (United States)

    Odia, G I; Aigbogun, O S

    1988-01-01

    This study assesses the differences in temperature sensitivity of skin areas. The subjects were required to associate the water content of test-tubes with the different heat sensations. The side of the test-tube was placed on the skin area and the temperature was matched with the subject's response. Analyses were limited to the warmth and cold sensations as generalizations can be made from these in terms of differences in the skin areas in heat perception. In the face, the temperature associated with warmth was significantly lower than in the forearm and the leg. This trend was different between the three areas in terms of the cold temperatures. The intra-individual difference suggests that results of skin sensation tests should be interpreted with some caution. Copyright © 1988 Australian Physiotherapy Association. Published by . All rights reserved.

  20. Improved Models and Tools for Prediction of Radiation Effects on Space Electronics in Wide Temperature Range, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — All NASA exploration systems operate in the extreme environments of space (Moon, Mars, etc.) and require reliable electronics capable of handling a wide temperature...

  1. Improved Models and Tools for Prediction of Radiation Effects on Space Electronics in Wide Temperature Range Project

    Data.gov (United States)

    National Aeronautics and Space Administration — All NASA exploration systems operate in the extreme environments of space (Moon, Mars, etc.) and require reliable electronics capable of handling a wide temperature...

  2. On-Board State-of-Health Estimation at a Wide Ambient Temperature Range in Lithium-Ion Batteries

    Directory of Open Access Journals (Sweden)

    Tiansi Wang

    2015-08-01

    Full Text Available A state-of-health (SOH estimation method for electric vehicles (EVs is presented with three main advantages: (1 it provides joint estimation of cell’s aging states in terms of power and energy (i.e., SOHP and SOHE—because the determination of SOHP and SOHE can be reduced to the estimation of the ohmic resistance increase and capacity loss, respectively, the ohmic resistance at nominal temperature will be taken as a health indicator, and the capacity loss is estimated based on a mechanistic model that is developed to describe the correlation between resistance increase and capacity loss; (2 it has wide applicability to various ambient temperatures—to eliminate the effects of temperature on the resistance, another mechanistic model about the resistance against temperature is presented, which can normalize the resistance at various temperatures to its standard value at the nominal temperature; and (3 it needs low computational efforts for on-board application—based on a linear equation of cell’s dynamic behaviors, the recursive least-squares (RLS algorithm is used for the resistance estimation. Based on the designed performance and validation experiments, respectively, the coefficients of the models are determined and the accuracy of the proposed method is verified. The results at different aging states and temperatures show good accuracy and reliability.

  3. Structure and tribological properties of MoCN-Ag coatings in the temperature range of 25–700 °C

    International Nuclear Information System (INIS)

    Shtansky, D.V.; Bondarev, A.V.; Kiryukhantsev-Korneev, Ph.V.; Rojas, T.C.; Godinho, V.; Fernández, A.

    2013-01-01

    The preparation of hard coatings with low friction coefficient over a wide temperature range is still a challenge for the tribological community. The development of new nanocomposite materials consisting of different metal-ceramic phases, each of which exhibiting self-lubricating characteristics at different temperatures, may help to solve this problem. We report on the structure and tribological properties of MoCN-Ag coatings deposited by magnetron co-sputtering of Mo and C (graphite) targets and simultaneous sputtering of an Ag target either in pure nitrogen or in a gaseous mixture of Ar + N 2 . The structure and elemental composition of the coatings were studied by means of X-ray diffraction, scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, Raman spectroscopy, and glow discharge optical emission spectroscopy. The tribological properties of the coatings against an Al 2 O 3 ball were investigated first at discrete temperatures of 25, 500, and 700 °C, and then during continuous heating in the temperature range of 25–700 °C. The coating structure and their respective wear tracks were also examined to elucidate their phase transformations during heat treatments. The lowest friction coefficients (<0.4) were observed in the temperature ranges of 25–100 °C and 400–700 °C and can be explained by the presence of a free amorphous carbon phase, which served as a lubricant at low temperatures, and by a positive role of silver and two phases forming at elevated temperatures, molybdenum oxide and silver molybdate, which provided lubrication above 400 °C. In the temperature range between 100 and 400 °C, the friction coefficient was relatively high. This problem is to be addressed in future works.

  4. Structure and tribological properties of MoCN-Ag coatings in the temperature range of 25–700 °C

    Energy Technology Data Exchange (ETDEWEB)

    Shtansky, D.V., E-mail: shtansky@shs.misis.ru [National University of Science and Technology “MISIS”, Leninsky Prospect 4, Moscow (Russian Federation); Bondarev, A.V.; Kiryukhantsev-Korneev, Ph.V. [National University of Science and Technology “MISIS”, Leninsky Prospect 4, Moscow (Russian Federation); Rojas, T.C.; Godinho, V.; Fernández, A. [Instituto de Ciencia de Materiales de Sevilla CSIC-US, Avda. Américo Vespucio 49, 41092 Sevilla (Spain)

    2013-05-15

    The preparation of hard coatings with low friction coefficient over a wide temperature range is still a challenge for the tribological community. The development of new nanocomposite materials consisting of different metal-ceramic phases, each of which exhibiting self-lubricating characteristics at different temperatures, may help to solve this problem. We report on the structure and tribological properties of MoCN-Ag coatings deposited by magnetron co-sputtering of Mo and C (graphite) targets and simultaneous sputtering of an Ag target either in pure nitrogen or in a gaseous mixture of Ar + N{sub 2}. The structure and elemental composition of the coatings were studied by means of X-ray diffraction, scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, Raman spectroscopy, and glow discharge optical emission spectroscopy. The tribological properties of the coatings against an Al{sub 2}O{sub 3} ball were investigated first at discrete temperatures of 25, 500, and 700 °C, and then during continuous heating in the temperature range of 25–700 °C. The coating structure and their respective wear tracks were also examined to elucidate their phase transformations during heat treatments. The lowest friction coefficients (<0.4) were observed in the temperature ranges of 25–100 °C and 400–700 °C and can be explained by the presence of a free amorphous carbon phase, which served as a lubricant at low temperatures, and by a positive role of silver and two phases forming at elevated temperatures, molybdenum oxide and silver molybdate, which provided lubrication above 400 °C. In the temperature range between 100 and 400 °C, the friction coefficient was relatively high. This problem is to be addressed in future works.

  5. The interrelationship between dengue incidence and diurnal ranges of temperature and humidity in a Sri Lankan city and its potential applications.

    Science.gov (United States)

    Ehelepola, N D B; Ariyaratne, Kusalika

    2015-01-01

    Temperature, humidity, and other weather variables influence dengue transmission. Published studies show how the diurnal fluctuations of temperature around different mean temperatures influence dengue transmission. There are no published studies about the correlation between diurnal range of humidity and dengue transmission. The goals of this study were to determine the correlation between dengue incidence and diurnal fluctuations of temperature and humidity in the Sri Lankan city of Kandy and to explore the possibilities of using that information for better control of dengue. We calculated the weekly dengue incidence in Kandy during the period 2003-2012, after collecting data on all of the reported dengue patients and estimated midyear populations. Data on daily maximum and minimum temperatures and night-time and daytime humidity were obtained from two weather stations, averaged, and converted into weekly data. The number of days per week with a diurnal temperature range (DTR) of >10°C and humidity range (DHR) of >20 and humidity. There were negative correlations between dengue incidence and a DTR >10°C and a DHR >20% with 3.3-week and 4-week lag periods, respectively. Additionally, positive correlations between dengue incidence and a DTR humidity in the future. We suggest ways and means to use this information for local dengue control and to mitigate the potential effects of the ongoing global reduction of DTR on dengue incidence.

  6. Peculiarities of high-amplitude dislocation internal friction in molybdenum single crystals of high purity in the temperature range 5.9 to 300 K

    International Nuclear Information System (INIS)

    Kaufmann, H.J.; Pal-Val, P.P.

    1982-01-01

    Amplitude dependences of internal friction in molybdenum single crystals of the orientations , , , are studied. The residual resistance ratio of the samples is (1 to 2) x 10 5 . The measurements are carried out at the frequency of 88 kHz in the temperature range 5.9 to 300 K. At low temperatures (<= 90 K) a maximum is found in the decrement amplitude dependences the height of which decreases rapidly with decreasing temperature. In this case the maximum position in the amplitude deformation axis does not change. In the same amplitude range a saturation region appears in the modulus defect amplitude dependences the magnitude of which also decreases rapidly with decreasing temperature. The observed behaviour of amplitude-dependent internal friction testifies to the fact that while decreasing temperature the losses connected with dislocation unpinning from the pinning centres decrease sharply. In molybdenum single crystals of lower purity or deformed at room temperature a maximum in the decrement amplitude dependences measured in the same amplitude range is absent. The peculiarities described cannot be explained in the framework of the theories presented. (author)

  7. Temperature dependence of the in intensity of diffraction maxima in roentgenograms of semiconductor compounds GaAs, InAs, InP in the 7-310 K temperature range

    International Nuclear Information System (INIS)

    Sirota, N.N.; Sidorov, A.A.

    1985-01-01

    Systematic investigation into temperature dependence of reflexes intensity of the Bragg coherent X-ray scattering with A 3 B 5 semiconductor compounds - gallium and indium arsenides and indium phosphides in a wide temperature range from helium to room temperatures is performed. It is shown that data on the temperature dependence of the coherent scattering reflex intensity permit to obtain comprehensive information on peculiarities of lattice dynamics of the objects investigated and their elastic properties. Measurement of reflex intensities near absolute zero enables direct experimental estimation of absolute values of root-mean-square atom dynamic shifts

  8. Measurement and modeling of density and viscosity of n-octanol-kerosene-phosphoric acid solutions in a temperature range 293.15-333.15 K

    Science.gov (United States)

    Ye, Changwen; Pei, Xiangjun; Liu, J. C.

    2016-12-01

    Densities and viscosities have been measured for the n-octanol + aviation kerosene (AK) + phosphoric acid (H3PO4) system with the mass fraction of H3PO4 in the range from w = 0 to 0.26 and in the temperature of 293.15-333.15 K. According to the experimental data, the measured viscosities were found well correlated with the temperature and mass fraction of H3PO4, which were fitted to regression equations. The result shows that the dilution effect of AK is obvious under the same temperature and mass fraction of H3PO4.

  9. Thermodynamics of aqueous methyldiethanolamine (MDEA) and methyldiethanolammonium chloride (MDEAH+Cl-) over a wide range of temperature and pressure: Apparent molar volumes, heat capacities, and isothermal compressibilities

    International Nuclear Information System (INIS)

    Hawrylak, B.; Palepu, R.; Tremaine, Peter R.

    2006-01-01

    Apparent molar volumes of aqueous methyldiethanolamine and its salt were determined with platinum vibrating tube densitometers over a range of temperatures from 283K= o , heat capacities C p o , and isothermal compressibilities κ T o . The standard partial molar volumes V o for the neutral amine and its salt show increasingly positive and negative values, respectively, at high temperatures and pressures, as predicted by corresponding states and group additivity arguments. The density model and the revised Helgeson-Kirkham-Flowers (HKF) model have been used to represent the temperature and pressure dependence of the standard partial molar properties to yield a full thermodynamic description of the system

  10. Oven controlled N++ [1 0 0] length-extensional mode silicon resonator with frequency stability of 1 ppm over industrial temperature range

    Science.gov (United States)

    You, Weilong; Pei, Binbin; Sun, Ke; Zhang, Lei; Yang, Heng; Li, Xinxin

    2017-10-01

    This paper presents an oven controlled N++ [1 0 0] length-extensional mode silicon resonator, with a lookup-table based control algorithm. The temperature coefficient of resonant frequency (TCF) of the N++ doped resonator is nonlinear, and there is a turnover temperature point at which the TCF is equal to zero. The resonator is maintained at the turnover point by Joule heating; this temperature is a little higher than the upper limit of the industrial temperature range. It is demonstrated that the control algorithm based on the thermoresistor on the substrate and the lookup table for heating voltage versus chip temperature is sufficiently accurate to achieve a frequency stability of  ±0.5 ppm over the industrial temperature range. Because only two leads are required for electrical heating and piezoresistive sensing, the power required for heating of this resonator can be potentially lower than that of the oscillators with closed-loop oven control algorithm. It is also shown that the phase noise can be suppressed at the turnover temperature because of the very low value of the TCF, which justifies the usage of the heating voltage as the excitation voltage of the Wheatstone half-bridge.

  11. Cu incorporated amorphous diamond like carbon (DLC) composites: An efficient electron field emitter over a wide range of temperature

    Science.gov (United States)

    Ahmed, Sk Faruque; Alam, Md Shahbaz; Mukherjee, Nillohit

    2018-03-01

    The effect of temperature on the electron field emission properties of copper incorporated amorphous diamond like carbon (a-Cu:DLC) thin films have been reported. The a-Cu:DLC thin films have been deposited on indium tin oxide (ITO) coated glass and silicon substrate by the radio frequency sputtering process. The chemical composition of the films was investigated using X-ray photoelectron spectroscopy and the micro structure was established using high resolution transmission electron microscopy. The sp2 and sp3 bonding ratio in the a-Cu:DLC have been analyzed by the Fourier transformed infrared spectroscopy studies. The material showed excellent electron field emission properties; which was optimized by varying the copper atomic percentage and temperature of the films. It was found that the threshold field and effective emission barrier were reduced significantly by copper incorporation as well as temperature and a detailed explanation towards emission mechanism has been provided.

  12. Devolatilization in the temperature range 300-600 K of liquids derived from wood pyrolysis and gasification

    Energy Technology Data Exchange (ETDEWEB)

    Carmen Branca; Colomba Di Blasi; Carmine Russo [Universita degli Studi di Napoli ' Federico II' , Naples (Italy). Dipartimento di Ingegneria Chimica

    2005-01-01

    A thermogravimetric system, previously developed for solid fuel degradation, has been modified to examine liquids obtained from conventional pyrolysis and updraft gasification of beech wood. Thermogravimetric curves in air show two main reaction stages. The first (temperatures {le} 600 K) concerns evaporation, formation and release of gases and formation of secondary char (coke). Then, at higher temperatures, heterogeneous combustion of secondary char takes place. A reliable procedure has been developed to carry out the first stage under assigned temperature using a PID controller and the applied heat flux as the manipulated variable. It has been found that the pyrolysis temperature does not affect significantly weight loss dynamics and amount of secondary char (approximately equal to 20% of the liquid on a dry basis). The thermogravimetric curves are well predicted by a global mechanism consisting of three parallel first-order reactions (activation energies of 66, 32 and 36 kJ/mol, respectively). Due to strong physico-chemical transformations (sample swelling and solidification) associated with secondary char formation, it is not possible to avoid ignition during heterogeneous combustion. Therefore, this reaction stage should be investigated separately after collection and adequate re-preparation of the charred sample. 29 refs., 7 figs., 1 tab.

  13. Experimental study of phase change materials for thermal storage in the temperature range of 300–400°C

    Directory of Open Access Journals (Sweden)

    Adinberg R.

    2014-01-01

    Full Text Available Phase change materials (PCM based on inorganic salts having a temperature of fusion between 300 and 400°C, were investigated using a lab scale set-up dedicated for studying latent heat storage for concentrating solar thermal power (CSP technology. This experimental system provides thermal measurements of PCM specimens of about 1000 g under the heating temperature up to 450°C and enables simultaneous investigation of calorimetric properties of the loaded materials and heat transfer effects developed in the thermal storage during the charge and discharge phases. The measurement technique comprised temperature and pressure sensors, a control and data acquisition system and a thermal analysis model used to evaluate the experimental data. Results of the thermochemical tests conducted with a thermal storage medium composed of the ternary eutectic mixture of carbonate salts (34.5% K2CO3–33.4% Na2CO3–32.1% Li2CO3 and Diphyl (synthetic thermal oil, max working temperature 400°C used as the heat transfer fluid are presented and discussed in this paper.

  14. Log and soil temperature profiles in managed headwater sub-basins in the Oregon coast range: implications for wildlife habitat

    Science.gov (United States)

    Matthew R. Kluber; Deanna H. Olson; Klaus J. Puettmann

    2013-01-01

    Down wood provides important faunal microhabitat in forests for many invertebrate taxa, small mammals, and amphibians. Habitat suitability of down wood as refugia is an increasing concern in managed forests of the US Pacifi c Northwest, where overstory reduction may result in both reduced down wood recruitment and increased temperatures within logs, which may make them...

  15. Differential growth of Legionella pneumophila strains within a range of amoebae at various temperatures associated with in-premise plumbing

    Science.gov (United States)

    The potential effect of in-premise plumbing temperatures (24, 32, 37 and 41 °C) on the growth of five different L. pneumophila strains within free-living amoebae (Acanthamoeba polyphaga, Hartmannella vermiformis and Naegleria fowleri) was examined. Compared to controls only fed E...

  16. Moisture rivals temperature in limiting photosynthesis by trees establishing beyond their cold-edge range limit under ambient and warmed conditions

    Science.gov (United States)

    Moyes, Andrew B.; Germino, Matthew J.; Kueppers, Lara M.

    2015-01-01

    Climate change is altering plant species distributions globally, and warming is expected to promote uphill shifts in mountain trees. However, at many cold-edge range limits, such as alpine treelines in the western United States, tree establishment may be colimited by low temperature and low moisture, making recruitment patterns with warming difficult to predict.

  17. Measurement of the specific heat of small vanadium particles in the normal- and superconducting state in the temperature range of 1.5-12 K

    International Nuclear Information System (INIS)

    Vergara Garcia, O.

    1982-01-01

    The specific heat of small crystalline vanadium particles in form of polyeders with diameters between 2.9 and 13.2 mm was measured in the temperature range of 1.5-12 K. Quantum effects are interpreted in the frame of theoretical models. (BEF)

  18. Heat capacity and Joule-Thomson coefficient of selected n-alkanes at 0.1 and 10 MPa in broad temperature ranges

    DEFF Research Database (Denmark)

    Regueira Muñiz, Teresa; Varzandeh, Farhad; Stenby, Erling Halfdan

    2017-01-01

    Isobaric heat capacity of six n-alkanes, i.e. n-hexane, n-octane, n-decane, n-dodecane, n-tetradecane and n-hexadecane, was determined with a Calvet type differential heat-flux calorimeter at 0.1 and 10 MPa in a broad temperature range. The measured isobaric heat capacity data were combined...

  19. High Ductility and Toughness of a Micro-duplex Medium-Mn Steel in a Large Temperature Range from -196 °C to 200 °C

    DEFF Research Database (Denmark)

    Chen, Si-lian; Hu, Jun; Zhang, Xiaodan

    2015-01-01

    intercritical annealing after forging and hot rolling. Ultrahigh ductility with a total elongation higher than 30% was achieved in the temperature range from - 196 degrees C to 200 degrees C and high impact toughness no less than 200 J at - 40 degrees C was obtained. Based on the analysis of microstructure...

  20. Thermodynamic properties, hysteresis behavior and stress-strain analysis of MgH2 thin films, studied over a wide temperature range

    NARCIS (Netherlands)

    Pivak, Y.; Schreuders, H.; Dam, B.

    2012-01-01

    Using hydrogenography, we investigate the thermodynamic parameters and hysteresis behavior in Mg thin films capped by Ta/Pd, in a temperature range from 333 K to 545 K. The enthalpy and entropy of hydride decomposition, ?Hdes = ?78.3 kJ/molH2, ?Sdes = ?136.1 J/K molH2, estimated from the Van't Hoff

  1. Phase composition of Al-Ti-Nb-Mo γ alloys in the heat-treatment temperature range: Calculation and experiment

    Science.gov (United States)

    Belov, N. A.; Dashkevich, N. I.; Bel'tyukova, S. O.

    2015-07-01

    The phase composition of TNM-type Al-Ti-Nb-Mo γ alloys at heat-treatment temperatures is quantitatively studied using the Thermo-Calc program package and experimental methods. Isothermal cross sections are calculated and the joint influence of two alloying elements on the phase composition of the alloy is determined at the mean concentration of a third component. Based on the calculations of vertical cross sections, the boundaries of the four-phase eutectoid reaction α → α2 + β + γ are found. The temperature is shown to significantly influence the phase compositions of the γ alloys, among them the mass fractions of various phases (α, β, γ,α2) and the element concentration in them.

  2. The Mechanical Properties of Wood of Different Moisture Content Within -200 Degrees to +200 Degrees C Temperature Range

    Science.gov (United States)

    Kollmann, Franz

    1941-01-01

    Systematic experiments were undertaken with special reference to the effect of gross specific weight (specific weight inclusive of pores) and the moisture content of wood. It was found that the modules of elasticity of wood at room temperature and frozen at -8 degrees is practically the same. The effect of moisture on the compression strength of frozen wood was explored as well as the flexural and impact strength of frozen wood and frozen laminated wood.

  3. Extending the upper temperature range of gas chromatography with all-silicon microchip columns using a heater/clamp assembly.

    Science.gov (United States)

    Ghosh, Abhijit; Johnson, Jacob E; Nuss, Johnathan G; Stark, Brittany A; Hawkins, Aaron R; Tolley, Luke T; Iverson, Brian D; Tolley, H Dennis; Lee, Milton L

    2017-09-29

    Miniaturization of gas chromatography (GC) instrumentation is of interest because it addresses current and future issues relating to compactness, portability and field application. While incremental advancements continue to be reported in GC with columns fabricated in microchips (referred to in this paper as "microchip columns"), the current performance is far from acceptable. This lower performance compared to conventional GC is due to factors such as pooling of the stationary phase in corners of non-cylindrical channels, adsorption of sensitive compounds on incompletely deactivated surfaces, shorter column lengths and less than optimum interfacing to injector and detector. In this work, a GC system utilizing microchip columns was developed that solves the latter challenge, i.e., microchip interfacing to injector and detector. A microchip compression clamp was constructed to heat the microchip (i.e., primary heater), and seal the injector and detector fused silica interface tubing to the inlet and outlet ports of the microchip channels with minimum extra-column dead volume. This clamp allowed occasional operation up to 375°C and routine operation up to 300°C. The compression clamp was constructed of a low expansion alloy, Kovar™, to minimize leaking due to thermal expansion mismatch at the interface during repeated thermal cycling, and it was tested over several months for more than one hundred injections without forming leaks. A 5.9m long microcolumn with rectangular cross section of 158μm×80μm, which approximately matches a 100μm i.d. cylindrical fused silica column, was fabricated in a silicon wafer using deep reactive ion etching (DRIE) and high temperature fusion bonding; finally, the channel was coated statically with a 1% vinyl, 5% phenyl, 94% methylpolysiloxane stationary phase. High temperature separations of C10-C40 n-alkanes and a commercial diesel sample were demonstrated using the system under both temperature programmed GC (TPGC) and thermal

  4. Generalization of Coffin-Manson relation in connection with the low-cycle fatigue in the temperature range 20-300 o C

    International Nuclear Information System (INIS)

    Radu, V.

    1992-01-01

    The low-cycle fatigue phenomenon in the framework of plastic deformation is studied considering the temperature parameter. The experimental results obtained for the plastic strain Δε p (1-7%), in the temperature range 20-300 o C are examined. The conclusion is that the lifetime, expressed by the number of stress cycles, N f , is given by the relation N f = C exp(-A/T)(Δε p ) β+αΔT , where T is the absolute temperature, Δε p is double of plastic deformation amplitude, and C, A, β, and α are material constants. This relation can be interpreted as being the generalization of a relation, known in literature as the 'Coffin-Manson relation', but which does not include the temperature parameter. The validation of this relation can be done either on the results presented in this paper or an those published in literature. (Author)

  5. Self-diffusion and molecular association of acetylsalicylic acid and methyl salicylate in methanol- d4 in the temperature range 278-318 K

    Science.gov (United States)

    Golubev, V. A.; Kumeev, R. S.; Gurina, D. L.; Nikiforov, M. Yu.

    2017-05-01

    The effect of concentration on the self-diffusion coefficients of acetylsalicylic acid and methyl salicylate in methanol- d4 is investigated in the temperature range of 278-318 K using NMR. It is found that the self-diffusion coefficients increase along with temperature and fall as concentration rises. Within the limit of an infinitely dilute solution, the effective radii of solute molecules, calculated using the Stokes-Einstein equation shrink as the temperature grows. It is shown that the observed reduction of effective radii is associated with an increase in the fraction of solute monomers as the temperature rises. The physicochemical parameters of heteroassociation of acetylsalicylic acid and methyl salicylate with methanol are determined.

  6. Negative Thermal Expansion over a Wide Temperature Range in Fe-Doped MnNiGe Composites.

    Science.gov (United States)

    Zhao, Wenjun; Sun, Ying; Liu, Yufei; Shi, Kewen; Lu, Huiqing; Song, Ping; Wang, Lei; Han, Huimin; Yuan, Xiuliang; Wang, Cong

    2018-01-01

    Fe-doped MnNiGe alloys were successfully synthesized by solid-state reaction. Giant negative thermal expansion (NTE) behaviors with the coefficients of thermal expansion (CTE) of -285.23 × 10 -6 K -1 (192-305 K) and -1167.09 × 10 -6 K -1 (246-305 K) have been obtained in Mn 0.90 Fe 0.10 NiGe and MnNi 0.90 Fe 0.10 Ge, respectively. Furthermore, these materials were combined with Cu in order to control the NTE properties. The results indicate that the absolute value of CTE gradually decreases with increasing Cu contents. In Mn 0.92 Fe 0.08 NiGe/ x %Cu, the CTE gradually changes from -64.92 × 10 -6 K -1 (125-274 K) to -4.73 × 10 -6 K -1 (173-229 K) with increasing value of x from 15 to 70. The magnetic measurements reveal that the NTE behaviors in this work are strongly correlated with the process of the magnetic phase transition and the introduction of Fe atoms could also change the spiral anti-ferromagnetic (s-AFM) state into ferromagnetic (FM) state at low temperature. Our study launches a new candidate for controlling thermal expansion properties of metal matrix materials which could have potential application in variable temperature environment.

  7. Negative Thermal Expansion over a Wide Temperature Range in Fe-Doped MnNiGe Composites

    Directory of Open Access Journals (Sweden)

    Wenjun Zhao

    2018-02-01

    Full Text Available Fe-doped MnNiGe alloys were successfully synthesized by solid-state reaction. Giant negative thermal expansion (NTE behaviors with the coefficients of thermal expansion (CTE of −285.23 × 10−6 K−1 (192–305 K and −1167.09 × 10−6 K−1 (246–305 K have been obtained in Mn0.90Fe0.10NiGe and MnNi0.90Fe0.10Ge, respectively. Furthermore, these materials were combined with Cu in order to control the NTE properties. The results indicate that the absolute value of CTE gradually decreases with increasing Cu contents. In Mn0.92Fe0.08NiGe/x%Cu, the CTE gradually changes from −64.92 × 10−6 K−1 (125–274 K to −4.73 × 10−6 K−1 (173–229 K with increasing value of x from 15 to 70. The magnetic measurements reveal that the NTE behaviors in this work are strongly correlated with the process of the magnetic phase transition and the introduction of Fe atoms could also change the spiral anti-ferromagnetic (s-AFM state into ferromagnetic (FM state at low temperature. Our study launches a new candidate for controlling thermal expansion properties of metal matrix materials which could have potential application in variable temperature environment.

  8. Pyrolysis of waste materials: Characterization and prediction of sorption potential across a wide range of mineral contents and pyrolysis temperatures.

    Science.gov (United States)

    Kah, Melanie; Sun, Huichao; Sigmund, Gabriel; Hüffer, Thorsten; Hofmann, Thilo

    2016-08-01

    Sewage sludge (50% mineral), manure (29%) and wood (pyrolysis across a wide range of mineral contents. A commercial plant-derived biochar (41% mineral) was also considered. The materials were extensively characterized and tested for their sorption towards the model sorbates benzene, naphthalene and pyrene. Plant-derived materials, regardless of their mineral content, developed micropores causing size exclusion of pyrene. Changes in properties and sorption behavior upon pyrolysis were generally consistent for the manure and wood series. A single regression equation developed on our data (including the sorbate hydrophobicity and sorbent polarity) provided excellent prediction of previously reported changes in sorption upon pyrolysis across a wide range of mineral content (up to 500°C). The sewage sludge series, however, followed a particular behavior, possibly due to very high mineral content (up to 67%). Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Hysteresis and Instability in Some IPRT Sensors Within Temperature Ranges Extending from -196 ^{circ }\\hbox {C} to 150 ^{circ }\\hbox {C}

    Science.gov (United States)

    Rusby, R. L.; Machin, D.

    2017-08-01

    Industrial platinum resistance thermometer (IPRT) sensors or probes suffer from some instability on cycling over significant ranges of temperature and, specifically, from hysteresis in which the resistance tends to follow different paths for increasing temperatures compared with decreasing temperatures. The effect is well known, and cases of quite large hysteresis have been reported in the literature. Therefore, in establishing calibration and measurement capabilities for IPRT calibrations it is important to include an assessment of the performance which can be expected of a `typical good' IPRT and to include this in the overall uncertainty which the laboratory can expect to achieve in such calibrations, even though the effect itself is outside the laboratory's control. This paper presents results which have been obtained in cycling IPRT probes from four sources within various temperature ranges of current interest at NPL, between -196 ^{circ }\\hbox {C} and 150 ^{circ }\\hbox {C}, to see what levels of hysteresis may be expected. The cycles were carried out quite quickly in order to detect the hysteresis before it was mitigated by relaxation effects, but the time dependence was not itself studied. In most cases, hysteresis was {<}0.0025 ^{circ }\\hbox {C} between 0 ^{circ }\\hbox {C} and 100 ^{circ }\\hbox {C}, and {<}0.0035 ^{circ }\\hbox {C} when the range extended down to -80 ^{circ }\\hbox {C} or up to 150 ^{circ }\\hbox {C}. Greater instability occurred when the sensors were cooled to -196 ^{circ }\\hbox {C}.

  10. Investigation of integral normal emmissivity of materials in the high temperature range with the aid of reflection furnace

    International Nuclear Information System (INIS)

    Shpil'rain, Eh.Eh.; Peletskij, V.Eh.; Kostanovskij, A.V.

    1976-01-01

    A special experimental procedure for investigating integral radiation capacity of a wide class of solids with the aid of a reverberatory furnace ''URAN-1'' has been developed. The description of the set-up is presented. For the range of 1300-2100 K, data are provided on the integral normal radiation capacity of niobium. The investigation results are compared with the data published in the literature

  11. Thermal Decomposition of Hydrocalumite over a Temperature Range of 400–1500°C and Its Structure Reconstruction in Water

    Directory of Open Access Journals (Sweden)

    Jiao Tian

    2014-01-01

    Full Text Available The thermal decomposition process and structure memory effect of hydrocalumite were investigated systematically for the first time over a wide temperature range of 400–1500°C. The calcined hydrocalumite samples and their rehydrated products were characterized by XRD, FT-IR, and SEM-EDX. The results show that the calcination products at temperatures ranging from 500 to 900°C are basically mayenite and lime, while one of the final products obtained by calcination at and above 1000°C is probably tricalcium aluminate (Ca3Al2O6. For the hydrocalumite samples calcined at temperatures below 1000°C, their lamellar structure can be completely recovered in deionized water at room temperature. However, the further increase of calcination temperature could impair the regeneration ability of hydrocalumite via contact with water. Upon calcination of hydrocalumite at 1000–1500°C followed by reaction with water, a stable compound tricalcium aluminate hexahydrate (Ca3Al2O6·6H2O was produced, which is the reason why less hydrocalumite could be regenerated.

  12. Comparison of acoustic properties of ceramics Cu O and YBa2 Cu3 Ox in the 5-310 K temperature range

    International Nuclear Information System (INIS)

    Pal'-Val', L.N.; Pal'-Val', P.P.; Natsik, V.D.; Dotsenko, V.I.

    1992-01-01

    The comparative study of ultrasound absorption and velocity of ceramic samples Cu O and YBa 2 Cu 3 O x (x=6.95 and 6.93) is made in temperature range 5-310 K and the frequency interval 47-370 khz. It is shown that the ultrasound absorption on spectra of Cu O and YBa 2 Cu 3 O x are similar in the temperature intervals 30-60 and 235-250 K. In these regions they involve absorption peaks P 1 and P 4 , the behavior of which with variations in frequency is identical for both the compounds. The absorption on spectra of Cu O and YBa 2 Cu 3 O x are most different in the temperature range 100-200 K. The spectrum of Cu O does not contain peaks P 2 and P 3 typical of the ceramics YBa 2 Cu 3 O x . The temperature dependence of sound velocity are investigated in the ceramics Cu O for the first time. The hysteresis similar to that in YBa 2 Cu 3 O x is observed under cycling. The hysteresis existence in Cu O and tetragonal sample of YBa 2 Cu 3 O x does not agree with the concept of tis twinning nature. Some phase transition seems to take place and the hysteresis is supposed to be due to the development of a low-temperature phase domain structure

  13. Thermal degradation of concrete in the temperature range from ambient to 315 degree C (600 degree F). Revision 10/96

    International Nuclear Information System (INIS)

    Kassir, M.K.; Bandyopadhyay, K.K.; Reich, M.

    1996-10-01

    This report is concerned with determining the effect of elevated temperatures on the behavior of concrete. Emphasis is placed on quantifying the degree of potential degradation of the physical properties of concrete in high-level waste storage tanks. The temperature elevation range of interest is from ambient to 315 C (600 F). The literature has been reviewed to examine the applicable experimental data and quantify the degradation in the concrete and reinforcing steel. Since many variables and test conditions control the results in the data base, upper and lower bounds of the degraded properties at temperatures applicable to the environments of the storage tanks are summarized and presented in explicit forms. For properties with large data bases, a normal logarithmic distribution of the data is assumed and a statistical analysis is carried out to find the mean and 84% values of the degraded property in the temperature range of interest. Such results are useful in assessing the effect of elevated temperatures on the structural behavior of the tanks. In addition, the results provide the technical basis for a parametric study that may be necessary to investigate the thermal aspects of the structural integrity of the tanks. 50 refs., 23 figs

  14. Revealing the extra-high ductility and toughness of micro+duplex medium+Mn steel in a large temperature range from 200 ℃ to -196 ℃

    DEFF Research Database (Denmark)

    Cao, Wenquan; Hu, Jun; Dong, Han

    2014-01-01

    A medium-Mn steel (0.2C5Mn) was processed by intercritical annealing at different temperature (625℃ and 650℃) after forging and hot rolling. The microstructures were characterized by transmission electron microscopy and the mechanical properties were measured by tensile tests and impact tests...... be obtained in the temperature range from 200℃ to -196℃. And significantly delayed transition from ductile to brittle and no less than 200J impact toughness at -40℃ could be obtained in the ART-annealed medium-Mn steel. Based on the analysis of microstructure and mechanical properties, the enhanced ductility...

  15. Excitons and continuum transitions of rubidium halides in the 10 - 26 eV photon energy range at low temperatures

    International Nuclear Information System (INIS)

    Zierau, W.; Skibowski, M.

    1975-04-01

    The reflection spectra of RbCl, RbBr and RbI single crystals were investigated for temperatures between 300 K and 8 K in order to study excitations from the Rb + 4p level (> approximately 16 eV) as well as the higher continuum transitions from the valence band (> approximately 10 eV). The measurements were performed by use of the synchrotron radiation of DESY. The sensitivity for detecting details of the fine structure was increased by simultaneously measuring the wavelength modulated spectra. The experimental procedure is briefly described. New spectral features have been resolved for the exciton multiplets from the Rb + 4p level. They are discussed in light of the predictions of a recent model for the Rb + 4p excitons based on ligand field theory. The continuum transitions associated with the valence band and the Rb + 4p level show characteristic structure which is compared with calculations of the joint density of states. (orig.) [de

  16. Shaft cryostat on the basis of a closed-circuit refrigerator for neutron powder diffraction studies in the temperature range 6-300 K

    International Nuclear Information System (INIS)

    Chernikov, A.N.; Zhuravlev, V.V.; Ul'yanov, V.A.; Trunov, V.A.; Bulkin, A.P.; Kolkhidashvili, M.R.

    2005-01-01

    A description of a cryostat on the basis of the closed cycle refrigerator CoolPower 5/100T for operation in the temperature range 6.2-300 K is presented. The cryostat is intended for a sample up to 18 mm in diameter and up to 100 mm of length. The reload of the sample placed into the ampoule, which is made of TiZr alloy, is performed at any temperature of the refrigerator with the help of an insert. Thermal connection between the sample and the heat exchanger of the refrigerator second step is performed with the help of heat exchange gas helium-4. The minimal temperature of the sample is 6.2 K at the accuracy of the temperature stabilization of the sample 0.1 K. Measurement and temperature stabilization is performed by a controller connected with a computer. Dependences of temperature measurements on time at cooling and heating are presented. The shaft cryostat was developed to carry out the experiments on neutron diffraction from powder samples

  17. Daily thermal fluctuations to a range of subzero temperatures enhance cold hardiness of winter-acclimated turtles.

    Science.gov (United States)

    Wiebler, James M; Kumar, Manisha; Muir, Timothy J

    2017-12-01

    Although seasonal increases in cold hardiness are well documented for temperate and polar ectotherms, relatively little is known about supplemental increases in cold hardiness during winter. Because many animals are exposed to considerable thermal variation in winter, they may benefit from a quick enhancement of cold tolerance prior to extreme low temperature. Hatchling painted turtles (Chrysemys picta) overwintering in their natal nests experience substantial thermal variation in winter, and recently, it was found that brief subzero chilling of winter-acclimated hatchlings decreases subsequent chilling-induced mortality, increases blood concentrations of glucose and lactate, and protects the brain from cryoinjury. Here, we further characterize that phenomenon, termed 'cold conditioning', by exposing winter-acclimated hatchling turtles to -3.5, -7.0, or -10.5 °C gradually or repeatedly via daily thermal fluctuations over the course of 5 days and assessing their survival of a subsequent cold shock to a discriminating temperature of -12.7 °C. To better understand the physiological response to cold conditioning, we measured changes in glucose and lactate concentrations in the liver, blood, and brain. Cold conditioning significantly increased cold-shock survival, from 9% in reference turtles up to 74% in cold-conditioned turtles, and ecologically relevant daily thermal fluctuations were at least as effective at conferring cryoprotection as was gradual cold conditioning. Cold conditioning increased glucose concentrations, up to 25 μmol g -1 , and lactate concentrations, up to 30 μmol g -1 , in the liver, blood, and brain. Turtles that were cold conditioned with daily thermal fluctuations accumulated more glucose in the liver, blood, and brain, and had lower brain lactate, than those gradually cold conditioned. Given the thermal variation to which hatchling painted turtles are exposed in winter, we suggest that the supplemental protection conferred by cold

  18. Estimating the daily global solar radiation spatial distribution from diurnal temperature ranges over the Tibetan Plateau in China

    International Nuclear Information System (INIS)

    Pan, Tao; Wu, Shaohong; Dai, Erfu; Liu, Yujie

    2013-01-01

    Highlights: ► Bristow–Campbell model was calibrated and validated over the Tibetan Plateau. ► Develop a simple method to rasterise the daily global solar radiation and get gridded information. ► The daily global solar radiation spatial distribution over the Tibetan Plateau was estimated. - Abstract: Daily global solar radiation is fundamental to most ecological and biophysical processes because it plays a key role in the local and global energy budget. However, gridded information about the spatial distribution of solar radiation is limited. This study aims to parameterise the Bristow–Campbell model for the daily global solar radiation estimation in the Tibetan Plateau and propose a method to rasterise the daily global solar radiation. Observed daily solar radiation and diurnal temperature data from eleven stations over the Tibetan Plateau during 1971–2010 were used to calibrate and validate the Bristow–Campbell radiation model. The extra-terrestrial radiation and clear sky atmospheric transmittance were calculated on a Geographic Information System (GIS) platform. Results show that the Bristow–Campbell model performs well after adjusting the parameters, the average Pearson’s correlation coefficients (r), Nash–Sutcliffe equation (NSE), ratio of the root mean square error to the standard deviation of measured data (RSR), and root mean-square error (RMSE) of 11 stations are 0.85, 2.81 MJ m −2 day −1 , 0.3 and 0.77 respectively. Gridded maximum and minimum average temperature data were obtained using Parameter-elevation Regressions on Independent Slopes Model (PRISM) and validated by the Chinese Ecosystem Research Network (CERN) stations’ data. The spatial daily global solar radiation distribution pattern was estimated and analysed by combining the solar radiation model (Bristow–Campbell model) and meteorological interpolation model (PRISM). Based on the overall results, it can be concluded that a calibrated Bristow–Campbell performs well

  19. Response of the global surface ozone distribution to Northern Hemisphere sea surface temperature changes: implications for long-range transport

    Science.gov (United States)

    Yi, Kan; Liu, Junfeng; Ban-Weiss, George; Zhang, Jiachen; Tao, Wei; Cheng, Yanli; Tao, Shu

    2017-07-01

    The response of surface ozone (O3) concentrations to basin-scale warming and cooling of Northern Hemisphere oceans is investigated using the Community Earth System Model (CESM). Idealized, spatially uniform sea surface temperature (SST) anomalies of ±1 °C are individually superimposed onto the North Pacific, North Atlantic, and North Indian oceans. Our simulations suggest large seasonal and regional variability in surface O3 in response to SST anomalies, especially in the boreal summer. The responses of surface O3 associated with basin-scale SST warming and cooling have similar magnitude but are opposite in sign. Increasing the SST by 1 °C in one of the oceans generally decreases the surface O3 concentrations from 1 to 5 ppbv. With fixed emissions, SST increases in a specific ocean basin in the Northern Hemisphere tend to increase the summertime surface O3 concentrations over upwind regions, accompanied by a widespread reduction over downwind continents. We implement the integrated process rate (IPR) analysis in CESM and find that meteorological O3 transport in response to SST changes is the key process causing surface O3 perturbations in most cases. During the boreal summer, basin-scale SST warming facilitates the vertical transport of O3 to the surface over upwind regions while significantly reducing the vertical transport over downwind continents. This process, as confirmed by tagged CO-like tracers, indicates a considerable suppression of intercontinental O3 transport due to increased tropospheric stability at lower midlatitudes induced by SST changes. Conversely, the responses of chemical O3 production to regional SST warming can exert positive effects on surface O3 levels over highly polluted continents, except South Asia, where intensified cloud loading in response to North Indian SST warming depresses both the surface air temperature and solar radiation, and thus photochemical O3 production. Our findings indicate a robust linkage between basin-scale SST

  20. Response of the global surface ozone distribution to Northern Hemisphere sea surface temperature changes: implications for long-range transport

    Directory of Open Access Journals (Sweden)

    K. Yi

    2017-07-01

    Full Text Available The response of surface ozone (O3 concentrations to basin-scale warming and cooling of Northern Hemisphere oceans is investigated using the Community Earth System Model (CESM. Idealized, spatially uniform sea surface temperature (SST anomalies of ±1 °C are individually superimposed onto the North Pacific, North Atlantic, and North Indian oceans. Our simulations suggest large seasonal and regional variability in surface O3 in response to SST anomalies, especially in the boreal summer. The responses of surface O3 associated with basin-scale SST warming and cooling have similar magnitude but are opposite in sign. Increasing the SST by 1 °C in one of the oceans generally decreases the surface O3 concentrations from 1 to 5 ppbv. With fixed emissions, SST increases in a specific ocean basin in the Northern Hemisphere tend to increase the summertime surface O3 concentrations over upwind regions, accompanied by a widespread reduction over downwind continents. We implement the integrated process rate (IPR analysis in CESM and find that meteorological O3 transport in response to SST changes is the key process causing surface O3 perturbations in most cases. During the boreal summer, basin-scale SST warming facilitates the vertical transport of O3 to the surface over upwind regions while significantly reducing the vertical transport over downwind continents. This process, as confirmed by tagged CO-like tracers, indicates a considerable suppression of intercontinental O3 transport due to increased tropospheric stability at lower midlatitudes induced by SST changes. Conversely, the responses of chemical O3 production to regional SST warming can exert positive effects on surface O3 levels over highly polluted continents, except South Asia, where intensified cloud loading in response to North Indian SST warming depresses both the surface air temperature and solar radiation, and thus photochemical O3 production. Our findings indicate a robust linkage

  1. Thermodynamic optimization of several (heat recovery steam generator) HRSG configurations for a range of exhaust gas temperatures

    International Nuclear Information System (INIS)

    Nadir, Mahmoud; Ghenaiet, Adel

    2015-01-01

    Design optimization of a (heat recovery steam generator) HRSG is essential due to its direct impact on large power generation combined cycles. This study is aimed at giving a thermodynamic comparison between the optimums of three configurations of HRSG operating at exhaust gas temperature (TOT) from 350 °C to 650 °C. The optimization results, using PSO (Particle Swarm Optimization) method, show that adding another pressure level allows achieving a higher pressure at the inlet of high pressure turbine, producing more steam quantities, destroying less exergy and finally producing more specific work independently of TOT. For a given value of 600 °C representative of TOT of recent gas turbines, an addition of a pressure level is shown to increase the specific work of about 17 kJ/kg, representing a benefit of about 10% for the steam cycle, whereas a third pressure level results in 8 kJ/kg increase in the specific work, corresponding to 4% in the steam cycle. - Highlights: • Three types of HRSG are optimized and compared between them for several TOT values. • Adding a pressure level leads to thermodynamic performance enhancement whatever TOT. • Adding a pressure level permits reaching higher optimal pressures whatever TOT value. • Adding a pressure level permits producing more steam quantities. • Superheater effectiveness tends to its highest possible value except for high TOTs

  2. Dielectric Properties of Marsh Vegetation in a Frequency Range of 0.1-18 GHz Under Variation of Temperature and Moisture

    Science.gov (United States)

    Romanov, A. N.; Kochetkova, T. D.; Suslyaev, V. I.; Shcheglova, A. S.

    2017-09-01

    Dielectric characteristics of some species of marsh vegetation: lichen Cladonia stellaris (Opiz) Pouzar, moss Sphagnum, and a representative of Bryidae mosses - Dicranum polysetum are studied in the frequency range from 100 MHz to 18 GHz. At a frequency of 1.41 GHz, the influence of temperature in the range from -12 to +20°C on the behavior of dielectric characteristics of mosses, lichens, and peat is studied. The dependences of the dielectric characteristics of vegetation on the volumetric wetness are established.

  3. Giant elastocaloric effect covering wide temperature range in columnar-grained Cu71.5Al17.5Mn11 shape memory alloy

    Directory of Open Access Journals (Sweden)

    Sheng Xu

    2016-10-01

    Full Text Available The elastocaloric effect in a columnar-grained Cu71.5Al17.5Mn11 shape memory alloy fabricated by directional solidification was investigated. A large entropy change of 25.0 J/kg K generated by the reversible martensitic transformation was demonstrated. The adiabatic temperature change of 12-13 K was directly measured, covering a wide temperature range of more than 100 K. The low applied stress with a specific elastocaloric ability of 100.8 K/GPa was identified and the potentially attainable operational temperature window as wide as more than 215 K was also discussed. The outstanding elastocaloric refrigeration capability, together with the low applying stress and uniform phase transformation, makes the columnar-grained Cu–Al–Mn shape memory alloy a promising material for solid-state refrigeration.

  4. Thermodynamic Properties, Hysteresis Behavior and Stress-Strain Analysis of MgH2 Thin Films, Studied over a Wide Temperature Range

    Directory of Open Access Journals (Sweden)

    Yevheniy Pivak

    2012-06-01

    Full Text Available Using hydrogenography, we investigate the thermodynamic parameters and hysteresis behavior in Mg thin films capped by Ta/Pd, in a temperature range from 333 K to 545 K. The enthalpy and entropy of hydride decomposition, ∆Hdes = −78.3 kJ/molH2, ∆Sdes = −136.1 J/K molH2, estimated from the Van't Hoff analysis, are in good agreement with bulk results, while the absorption thermodynamics, ∆Habs = −61.6 kJ/molH2, ∆Sabs = −110.9 J/K molH2, appear to be substantially affected by the clamping of the film to the substrate. The clamping is negligible at high temperatures, T > 523 K, while at lower temperatures, T < 393 K, it is considerable. The hysteresis at room temperature in Mg/Ta/Pd films increases by a factor of 16 as compared to MgH2 bulk. The hysteresis increases even further in Mg/Pd films, most likely due to the formation of a Mg-Pd alloy at the Mg/Pd interface. The stress–strain analysis of the Mg/Ta/Pd films at 300–333 K proves that the increase of the hysteresis occurs due to additional mechanical work during the (de-hydrogenation cycle. With a proper temperature correction, our stress–strain analysis quantitatively and qualitatively explains the hysteresis behavior in thin films, as compared to bulk, over the whole temperature range.

  5. Absolute Viscosities of Vegetable Oils at Different Temperatures and Shear Rate Range of 64.5 to 4835 s−1

    Directory of Open Access Journals (Sweden)

    Lemuel M. Diamante

    2014-01-01

    Full Text Available A study was carried out to determine the effect of higher shear rates (64.5 to 4835 s−1 on the absolute viscosities of different vegetable oils at different temperatures (26 to 90°C. The absolute viscosities of the different vegetable oils were determined using a Lamy Viscometer RM100, a rotating viscometer with coaxial cylinder. The torque of each sample at different temperatures was recorded at different shear rates. Based on the rheograms (plot of mean shear stress against shear rate, all of the vegetable oils studied were found to be Newtonian fluids. Rice bran oil was the most viscous (0.0398 Pa·s at 38°C while walnut oil was the least viscous (0.0296 Pa·s at 38°C among the oils studied. The higher shear range used did not significantly affect the absolute viscosities of the vegetable oils at the different temperatures. The absolute viscosities of the vegetable oils decreased with increasing temperature and can be fitted with an Arrhenius type relationship. The activation energies for the different vegetable oils ranged from 21 to 30 kJ/mole. The peanut and safflower oils had the highest and lowest activation energies, respectively. This means that greater energy was needed to effect a viscosity change in the peanut oil.

  6. The response of polymethyl methacrylate (PMMA) subjected to large strains, high strain rates, high pressures, a range in temperatures, and variations in the intermediate principal stress

    Science.gov (United States)

    Holmquist, T. J.; Bradley, J.; Dwivedi, A.; Casem, D.

    2016-05-01

    This article presents the response of polymethyl methacrylate (PMMA) subjected to large strains, high strain rates, high pressures, a range in temperatures, and variations in the intermediate principal stress. Laboratory data from the literature, and new test data provided here, are used in the evaluation. The new data include uniaxial stress compression tests (at various strain rates and temperatures) and uniaxial stress tension tests (at low strain rates and ambient temperatures). The compression tests include experiments at ˙ɛ = 13,000 s-1, significantly extending the range of known strain rate data. The observed behavior of PMMA includes the following: it is brittle in compression at high rates, and brittle in tension at all rates; strength is dependent on the pressure, strain, strain rate, temperature, and the intermediate principal stress; the shear modulus increases as the pressure increases; and it is highly compressible. Also presented are novel, high velocity impact tests (using high-speed imaging) that provide insight into the initiation and evolution of damage. Lastly, computational constitutive models for pressure, strength, and failure are presented that provide responses that are in good agreement with the laboratory data. The models are used to compute several ballistic impact events for which experimental data are available.

  7. Changes in the daily range of the air temperature in the mountainous part of Slovakia within the possible context of global warming

    Directory of Open Access Journals (Sweden)

    Ingrid Damborská

    2016-02-01

    Full Text Available Mean global and regional air temperatures have increased in the last several decades more than at any time during the history of instrumental measurement. Because of changes in the energy balance of the daily regime of the Earth's surface, it seems that the daily minimum temperature will increase more than the daily maximum one. The general theoretical analysis have indicated the daily range (TR of air temperatures decrease, but they are also influenced by several other factors such as topography, wind, solar radiation, cloudiness, humidity, soil moisture, upwind and lee effects, etc. This paper contains a sample from an analysis of past conditions showing changes in TR at several Slovak stations from 1961–2010 and possible changes in TR up to the time frame of the year 2100 using climate change scenarios based on four climatic models adopted in Slovakia (global CGCM3.1 and ECHAM5, regional KNMI and MPI and three emission scenarios (IPCC SRES A2, B1 and A1B. The trends and correlations of daily air temperature ranges with other climatic variables were analyzed.

  8. Diurnal Cycles of High Resolution Land Surface Temperatures (LSTs) Determined from UAV Platforms Across a Range of Surface Types

    Science.gov (United States)

    McCabe, M.; Rosas Aguilar, J.; Parkes, S. D.; Aragon, B.

    2017-12-01

    Observation of land surface temperature (LST) has many practical uses, from studying boundary layer dynamics and land-atmosphere coupling, to investigating surface properties such as soil moisture status, heat stress and surface heat fluxes. Typically, LST is observed via satellite based sensors such as LandSat or via point measurements using IR radiometers. These measurements provide either good spatial coverage and resolution or good temporal coverage. However, neither are able to provide the needed spatial and temporal resolution for many of the research applications described above. Technological developments in the use of Unmanned Aerial Vehicles (UAVs), together with small thermal frame cameras, has enabled a capacity to overcome this spatiotemporal constraint. Utilising UAV platforms to collect LST measurements across diurnal cycles provides an opportunity to study how meteorological and surface properties vary in both space and time. Here we describe the collection of LST data from a multi-rotor UAV across a study domain that is observed multiple times throughout the day. Flights over crops of Rhodes grass and alfalfa, along with a bare desert surface, were repeated with between 8 and 11 surveys covering the period from early morning to sunset. Analysis of the collected thermal imagery shows that the constructed LST maps illustrate a strong diurnal cycle consistent with expected trends, but with considerable spatial and temporal variability observed within and between the different domains. These results offer new insights into the dynamics of land surface behavior in both dry and wet soil conditions and at spatiotemporal scales that are unable to be replicated using traditional satellite platforms.

  9. Broad temperature range of cubic blue phase present in simple binary mixture systems containing rodlike Schiff base mesogens with tolane moiety.

    Science.gov (United States)

    Huang, Chiung-Cheng; Chen, Yu-Hao; Chen, Sheng-Yen; Sun, Yi-Zeng; Wu, Zong-Ye; Yu, Mei-Ching; Chen, Bo-Hao; Hsu, I-Jui; Wu, Lai-Chin; Lee, Jey-Jau

    2016-03-28

    Four simple rodlike Schiff base mesogens with tolane moiety were synthesized and applied to stabilize cubic blue phases (BPs) in simple binary mixture systems for the first time. When the chiral additive or was added into a chiral salicylaldimine-based compound, the temperature range of the cubic BP could be extended by more than 20 °C. However, when the chiral Schiff base mesogen was blended with chiral dopant possessing opposite handedness, , BPs could not be observed. Interestingly, the widest temperature range of the cubic BPs (∼35 °C) could be induced by adding the rodlike chiral dopant or into the rodlike racemic Schiff base mesogen with hydroxyl group. On the basis of our experimental results and molecular modeling, the appearance and temperature range of the BPs are affected by the dipole moment and the biaxiality of the molecular geometry. Accordingly, we demonstrated that the hydroxyl group and the methyl branch in this type of Schiff base mesogen play an important role in the stabilization of BPs.

  10. Genome-wide signatures of flowering adaptation to climate temperature: regional analyses in a highly diverse native range of Arabidopsis thaliana.

    Science.gov (United States)

    Tabas-Madrid, Daniel; Méndez-Vigo, Belén; Arteaga, Noelia; Marcer, Arnald; Pascual-Montano, Alberto; Weigel, Detlef; Xavier Picó, F; Alonso-Blanco, Carlos

    2018-03-08

    Current global change is fueling an interest to understand the genetic and molecular mechanisms of plant adaptation to climate. In particular, altered flowering time is a common strategy for escape from unfavorable climate temperature. In order to determine the genomic bases underlying flowering time adaptation to this climatic factor, we have systematically analysed a collection of 174 highly diverse A. thaliana accessions from the Iberian Peninsula. Analyses of 1.88 million SNPs provide evidence for a spatially heterogeneous contribution of demographic and adaptive processes to geographic patterns of genetic variation. Mountains appear to be allele dispersal barriers, whereas the relationship between flowering time and temperature depended on the precise temperature range. Environmental genome-wide associations (EGWA) supported an overall genome adaptation to temperature, with 9.4% of the genes showing significant associations. Furthermore, phenotypic genome-wide associations (PGWA) provided a catalogue of candidate genes underlying flowering time variation. Finally, comparison of EGWA and PGWA genomic regions identified known (TSF, FRL1 and CKB1) and new (ESM1 and VDAC5) genes as candidates for adaptation to climate temperature by altered flowering time. Thus, this regional collection provides an excellent resource to address the spatial complexity of climate adaptation in annual plants. This article is protected by copyright. All rights reserved.

  11. Sample environment for neutron scattering measurements of internal stresses in engineering materials in the temperature range of 6 K to 300 K

    Science.gov (United States)

    Kirichek, O.; Timms, J. D.; Kelleher, J. F.; Down, R. B. E.; Offer, C. D.; Kabra, S.; Zhang, S. Y.

    2017-02-01

    Internal stresses in materials have a considerable effect on material properties including strength, fracture toughness, and fatigue resistance. The ENGIN-X beamline is an engineering science facility at ISIS optimized for the measurement of strain and stress using the atomic lattice planes as a strain gauge. Nowadays, the rapidly rising interest in the mechanical properties of engineering materials at low temperatures has been stimulated by the dynamic development of the cryogenic industry and the advanced applications of the superconductor technology. Here we present the design and discuss the test results of a new cryogenic sample environment system for neutron scattering measurements of internal stresses in engineering materials under a load of up to 100 kN and in the temperature range of 6 K to 300 K. Complete cooling of the system starting from the room temperature down to the base temperature takes around 90 min. Understanding of internal stresses in engineering materials at cryogenic temperatures is vital for the modelling and designing of cutting-edge superconducting magnets and other superconductor based applications.

  12. Thermal conductivity of an organic phase change material/expanded graphite composite across the phase change temperature range and a novel thermal conductivity model

    International Nuclear Information System (INIS)

    Ling, Ziye; Chen, Jiajie; Xu, Tao; Fang, Xiaoming; Gao, Xuenong; Zhang, Zhengguo

    2015-01-01

    Highlights: • Expanded graphite can improve thermal conductivity of RT44HC by 20–60 times. • Thermal conductivity of PCM/EG composites keeps constant before/after melting. • Thermal conductivity of PCMs nearly doubled during phase changing. • Thermal conductivity of composite PCM increases with density and percentage of EG. • The simple model predicts thermal conductivity of EG-based composites accurately. - Abstract: This work studies factors that affect the thermal conductivity of an organic phase change material (PCM), RT44HC/expanded graphite (EG) composite, which include: EG mass fraction, composite PCM density and temperature. The increase of EG mass fraction and bulk density will both enhance thermal conductivity of composite PCMs, by up to 60 times. Thermal conductivity of RT44HC/EG composites remains independent on temperature outside the phase change range (40–45 °C), but nearly doubles during the phase change. The narrow temperature change during the phase change allows the maximum heat flux or minimum temperature for heat source if attaching PCMs to a first (constant temperature) or second (constant heat flux) thermal boundary. At last, a simple thermal conductivity model for EG-based composites is put forward, based on only two parameters: mass fraction of EG and bulk density of the composite. This model is validated with experiment data presented in this paper and in literature, showing this model has general applicability to any composite of EG and poor thermal conductive materials

  13. New Insight into Time-Temperature Correlation for Polymer Relaxations Ranging from Secondary Relaxation to Terminal Flow: Application of a Universal and Developed WLF Equation

    Directory of Open Access Journals (Sweden)

    Yonggang Shangguan

    2017-11-01

    Full Text Available The three equations involved in the time-temperature superposition (TTS of a polymer, i.e., Williams–Landel–Ferry (WLF, Vogel–Fulcher–Tammann–Hesse (VFTH and the Arrhenius equation, were re-examined, and the mathematical equivalence of the WLF form to the Arrhenius form was revealed. As a result, a developed WLF (DWLF equation was established to describe the temperature dependence of relaxation property for the polymer ranging from secondary relaxation to terminal flow, and its necessary criteria for universal application were proposed. TTS results of viscoelastic behavior for different polymers including isotactic polypropylene (iPP, high density polyethylene (HDPE, low density polyethylene (LDPE and ethylene-propylene rubber (EPR were well achieved by the DWLF equation at high temperatures. Through investigating the phase-separation behavior of poly(methyl methacrylate/poly(styrene-co-maleic anhydride (PMMA/SMA and iPP/EPR blends, it was found that the DWLF equation can describe the phase separation behavior of the amorphous/amorphous blend well, while the nucleation process leads to a smaller shift factor for the crystalline/amorphous blend in the melting temperature region. Either the TTS of polystyrene (PS and PMMA or the secondary relaxations of PMMA and polyvinyl chloride (PVC confirmed that the Arrhenius equation can be valid only in the high temperature region and invalid in the vicinity of glass transition due to the strong dependence of apparent activation energy on temperature; while the DWLF equation can be employed in the whole temperature region including secondary relaxation and from glass transition to terminal relaxation. The theoretical explanation for the universal application of the DWLF equation was also revealed through discussing the influences of free volume and chemical structure on the activation energy of polymer relaxations.

  14. Improvement of the Measurement Range and Temperature Characteristics of a Load Sensor Using a Quartz Crystal Resonator with All Crystal Layer Components.

    Science.gov (United States)

    Murozaki, Yuichi; Sakuma, Shinya; Arai, Fumihito

    2017-05-08

    Monitoring multiple biosignals, such as heart rate, respiration cycle, and weight transitions, contributes to the health management of individuals. Specifically, it is possible to measure multiple biosignals using load information obtained through contact with the environment, such as a chair and bed, in daily use. A wide-range load sensor is essential since load information contains multiple biosignals with various load ranges. In this study, a load sensor is presented by using a quartz crystal resonator (QCR) with a wide measurement range of 1.5 × 10⁶ (0.4 mN to 600 N), and its temperature characteristic of load is improved to -7 Hz/°C (-18 mN/°C). In order to improve the measurement range of the load, a design method of this sensor is proposed by restraining the buckling of QCR and by using a thinner QCR. The proposed sensor allows a higher allowable load with high sensitivity. The load sensor mainly consists of three layers, namely a QCR layer and two holding layers. As opposed to the conventional holding layer composed of silicon, quartz crystal is utilized for the holding layers to improve the temperature characteristic of the load sensor. In the study, multiple biosignals, such as weight and pulse, are detected by using a fabricated sensor.

  15. temperature

    Directory of Open Access Journals (Sweden)

    G. Polt

    2015-10-01

    Full Text Available In-situ X-ray diffraction was applied to isotactic polypropylene with a high volume fraction of α-phase (α-iPP while it has been compressed at temperatures below and above its glass transition temperature Tg. The diffraction patterns were evaluated by the Multi-reflection X-ray Profile Analysis (MXPA method, revealing microstructural parameters such as the density of dislocations and the size of coherently scattering domains (CSD-size. A significant difference in the development of the dislocation density was found compared to compression at temperatures above Tg, pointing at a different plastic deformation mechanism at these temperatures. Based on the individual evolutions of the dislocation density and CSD-size observed as a function of compressive strain, suggestions for the deformation mechanisms occurring below and above Tg are made.

  16. Factors affecting date of implantation, parturition, and den entry estimated from activity and body temperature in free-ranging brown bears.

    Science.gov (United States)

    Friebe, Andrea; Evans, Alina L; Arnemo, Jon M; Blanc, Stéphane; Brunberg, Sven; Fleissner, Günther; Swenson, Jon E; Zedrosser, Andreas

    2014-01-01

    Knowledge of factors influencing the timing of reproduction is important for animal conservation and management. Brown bears (Ursus arctos) are able to vary the birth date of their cubs in response to their fat stores, but little information is available about the timing of implantation and parturition in free-ranging brown bears. Body temperature and activity of pregnant brown bears is higher during the gestation period than during the rest of hibernation and drops at parturition. We compared mean daily body temperature and activity levels of pregnant and nonpregnant females during preimplantation, gestation, and lactation. Additionally we tested whether age, litter size, primiparity, environmental conditions, and the start of hibernation influence the timing of parturition. The mean date of implantation was 1 December (SD = 12), the mean date of parturition was 26 January (SD = 12), and the mean duration of the gestation period was 56 days (SD = 2). The body temperature of pregnant females was higher during the gestation and lactation periods than that of nonpregnant bears. The body temperature of pregnant females decreased during the gestation period. Activity recordings were also used to determine the date of parturition. The parturition dates calculated with activity and body temperature data did not differ significantly and were the same in 50% of the females. Older females started hibernation earlier. The start of hibernation was earlier during years with favorable environmental conditions. Dates of parturition were later during years with good environmental conditions which was unexpected. We suggest that free-ranging pregnant brown bears in areas with high levels of human activities at the beginning of the denning period, as in our study area, might prioritize investing energy in early denning than in early parturition during years with favorable environmental conditions, as a strategy to prevent disturbances caused by human.

  17. Seasonal microbial and nutrient responses during a 5-year reduction in the daily temperature range of soil in a Chihuahuan Desert ecosystem.

    Science.gov (United States)

    van Gestel, Natasja C; Dhungana, Nirmala; Tissue, David T; Zak, John C

    2016-01-01

    High daily temperature range of soil (DTRsoil) negatively affects soil microbial biomass and activity, but its interaction with seasonal soil moisture in regulating ecosystem function remains unclear. For our 5-year field study in the Chihuahuan Desert, we suspended shade cloth 15 cm above the soil surface to reduce daytime temperature and increase nighttime soil temperature compared to unshaded plots, thereby reducing DTRsoil (by 5 ºC at 0.2 cm depth) without altering mean temperatures. Microbial biomass production was primarily regulated by seasonal precipitation with the magnitude of the response dependent on DTRsoil. Reduced DTRsoil more consistently increased microbial biomass nitrogen (MBN; +38%) than microbial biomass carbon (MBC) with treatment responses being similar in spring and summer. Soil respiration depended primarily on soil moisture with responses to reduced DTRsoil evident only in wetter summer soils (+53%) and not in dry spring soils. Reduced DTRsoil had no effect on concentrations of dissolved organic C, soil organic matter (SOM), nor soil inorganic N (extractable NO3 (-)-N + NH4 (+)-N). Higher MBN without changes in soil inorganic N suggests faster N cycling rates or alternate sources of N. If N cycling rates increased without a change to external N inputs (atmospheric N deposition or N fixation), then productivity in this desert system, which is N-poor and low in SOM, could be negatively impacted with continued decreases in daily temperature range. Thus, the future N balance in arid ecosystems, under conditions of lower DTR, seems linked to future precipitation regimes through N deposition and regulation of soil heat load dynamics.

  18. Zero thermal expansion and ferromagnetism in cubic Sc(1-x)M(x)F3 (M = Ga, Fe) over a wide temperature range.

    Science.gov (United States)

    Hu, Lei; Chen, Jun; Fan, Longlong; Ren, Yang; Rong, Yangchun; Pan, Zhao; Deng, Jinxia; Yu, Ranbo; Xing, Xianran

    2014-10-01

    The rare physical property of zero thermal expansion (ZTE) is intriguing because neither expansion nor contraction occurs with temperature fluctuations. Most ZTE, however, occurs below room temperature. It is a great challenge to achieve isotropic ZTE at high temperatures. Here we report the unconventional isotropic ZTE in the cubic (Sc1-xMx)F3 (M = Ga, Fe) over a wide temperature range (linear coefficient of thermal expansion (CTE), αl = 2.34 × 10(-7) K(-1), 300-900 K). Such a broad temperature range with a considerably negligible CTE has rarely been documented. The present ZTE property has been designed using the introduction of local distortions in the macroscopic cubic lattice by heterogeneous cation substitution for the Sc site. Even though the macroscopic crystallographic structure of (Sc0.85Ga0.05Fe0.1)F3 adheres to the cubic system (Pm3̅m) according to the results of X-ray diffraction, the local structure exhibits a slight rhombohedral distortion. This is confirmed by pair distribution function analysis of synchrotron radiation X-ray total scattering. This local distortion may weaken the contribution from the transverse thermal vibration of fluorine atoms to negative thermal expansion, and thus may presumably be responsible for the ZTE. In addition, the present ZTE compounds of (Sc1-xMx)F3 can be functionalized to exhibit high-Tc ferromagnetism and a narrow-gap semiconductor feature. The present study shows the possibility of obtaining ZTE materials with multifunctionality in future work.

  19. Factors affecting date of implantation, parturition, and den entry estimated from activity and body temperature in free-ranging brown bears.

    Directory of Open Access Journals (Sweden)

    Andrea Friebe

    Full Text Available Knowledge of factors influencing the timing of reproduction is important for animal conservation and management. Brown bears (Ursus arctos are able to vary the birth date of their cubs in response to their fat stores, but little information is available about the timing of implantation and parturition in free-ranging brown bears. Body temperature and activity of pregnant brown bears is higher during the gestation period than during the rest of hibernation and drops at parturition. We compared mean daily body temperature and activity levels of pregnant and nonpregnant females during preimplantation, gestation, and lactation. Additionally we tested whether age, litter size, primiparity, environmental conditions, and the start of hibernation influence the timing of parturition. The mean date of implantation was 1 December (SD = 12, the mean date of parturition was 26 January (SD = 12, and the mean duration of the gestation period was 56 days (SD = 2. The body temperature of pregnant females was higher during the gestation and lactation periods than that of nonpregnant bears. The body temperature of pregnant females decreased during the gestation period. Activity recordings were also used to determine the date of parturition. The parturition dates calculated with activity and body temperature data did not differ significantly and were the same in 50% of the females. Older females started hibernation earlier. The start of hibernation was earlier during years with favorable environmental conditions. Dates of parturition were later during years with good environmental conditions which was unexpected. We suggest that free-ranging pregnant brown bears in areas with high levels of human activities at the beginning of the denning period, as in our study area, might prioritize investing energy in early denning than in early parturition during years with favorable environmental conditions, as a strategy to prevent disturbances caused by human.

  20. Coefficient of volume expansion - thermo acoustical parameters in polystyrene, nylon-6 and teflon in the temperature range 173 degree K to 383 degree K

    International Nuclear Information System (INIS)

    Reddy, R.R.; Ahammed, Y.N.; Kumap, M.R.; Rag, T.V.R.; Sharma, B.K.

    1997-01-01

    Thermo acoustical parameters of polymers viz. Polystyrene, Nylon-6 and Teflon have been evaluated at temperature between 173 degree K and 383 degree K in terms of the coefficient of volume expansion, on the assumption that the Moelwyn-Hughes parameter is the dominant factor. Parameters such as the Beyer's nonlinearity parameter, Moelwyn-Hughes parameter, the isothermal, isobaric and isochoric Gruineisen parameters, the repulsive exponent of intermolecular potential, fractional available volume, and the Sharma thermo acoustical parameter S sub 0 have been evaluated through simple relationships. The interrelationships between the isobaric and isochoric Gruneisen and acoustical, parameters have been examined and analysed in these polymers over a wide temperature range. The results have been used to develop understanding of the significance of microscopic factors such as molecular order and intermolecular forces upon macroscopic thermo acoustical properties. The Sharma's parameter S sub 0 remains invariant with temperature over a wide range and retains its characteristic value i.e. 1.1 1+/- 0.01 as observed in case of several systems existing either in a liquid state or in a solid state. The present treatment has the distinct advantage of calculating several thermo acoustical parameters through simple interrelationships from the knowledge of volume expansivity alone

  1. Photometric analysis of the structure evolution on the Pb-19.4%Sn melt surface in the S-L temperature range

    Directory of Open Access Journals (Sweden)

    Lyakhovitskii M.M.

    2011-05-01

    Full Text Available The structure evolution of alloys in solidification range is considered as the first-order phase transformation from the solid state to the liquid one, which occurs by the mechanism of nucleation and growth of more symmetrical phase to less symmetrical crystalline phase. The kinetic regularities of this transformation are studied by the method of the photometric analysis of structure images (PHASI, which makes it possible to establish the temperature dependence of the relationship between the solid and liquid phases and their distribution on the melt surface. The PHASI method is based on the combined analysis of the brightness spectra of the visible light reflections from the sample surface and of the distribution of its scattering centers in different intensity intervals. The data on the structure evolution of the Sn+19.4%Pb alloy upon melting and solidification were considered in parallel with the measured spectra of sound signals. It was revealed that a distinct maximum is observed in the temperature dependence of radiation energy in the temperature range of phase transformation from the liquid into the solid state and hot crack formation occurs near the transition zone in the region of the contact of the ingot with the crucible.

  2. The dynamic compressive behavior and constitutive modeling of D1 railway wheel steel over a wide range of strain rates and temperatures

    Directory of Open Access Journals (Sweden)

    Lin Jing

    Full Text Available The dynamic compressive behavior of D1 railway wheel steel at high strain rates was investigated using a split Hopkinson pressure bar (SHPB apparatus. Three types of specimens, which were derived from the different positions (i.e., the rim, web and hub of a railway wheel, were tested over a wide range of strain rates from 10−3 s−1 to 2.4 × 103 s−1 and temperatures from 213 K to 973 K. Influences of the strain rate and temperature on flow stress were discussed, and rate- and temperature-dependent constitutive relationships were assessed by the Cowper-Symonds model, Johnson-Cook model and a physically-based model, respectively. The experimental results show that the compressive true stress versus true strain response of D1 wheel steel is strain rate-dependent, and the strain hardening rate during the plastic flow stage decreases with the elevation of strain rate. Besides, the D1 wheel steel displays obvious temperature-dependence, and the third-type strain aging (3rd SA is occurred at the temperature region of 673–973 K at a strain rate of ∼1500 s−1. Comparisons of experimental results with theoretical predictions indicate that the physically-based model has a better prediction capability for the 3rd SA characteristic of the tested D1 wheel steel. Keywords: Railway wheel steel, SHPB, Strain rate, Temperature effect, Strain aging

  3. Fracture toughness and fracture behavior of CLAM steel in the temperature range of 450 °C-550 °C

    Science.gov (United States)

    Zhao, Yanyun; Liang, Mengtian; Zhang, Zhenyu; Jiang, Man; Liu, Shaojun

    2018-04-01

    In order to analyze the fracture toughness and fracture behavior (J-R curves) of China Low Activation Martensitic (CLAM) steel under the design service temperature of Test Blanket Module of the International Thermonuclear Experimental Reactor, the quasi-static fracture experiment of CLAM steel was carried out under the temperature range of 450 °C-550 °C. The results indicated that the fracture behavior of CLAM steel was greatly influenced by test temperature. The fracture toughness increased slightly as the temperature increased from 450 °C to 500 °C. In the meanwhile, the fracture toughness at 550 °C could not be obtained due to the plastic deformation near the crack tip zone. The microstructure analysis based on the fracture topography and the interaction between dislocations and lath boundaries showed two different sub-crack propagation modes: growth along 45° of the main crack direction at 450 °C and growth perpendicular to the main crack at 500 °C.

  4. Method to estimate the effective temperatures of late-type giants using line-depth ratios in the wavelength range 0.97-1.32 μm

    Science.gov (United States)

    Taniguchi, Daisuke; Matsunaga, Noriyuki; Kobayashi, Naoto; Fukue, Kei; Hamano, Satoshi; Ikeda, Yuji; Kawakita, Hideyo; Kondo, Sohei; Sameshima, Hiroaki; Yasui, Chikako

    2018-02-01

    The effective temperature, one of the most fundamental atmospheric parameters of a star, can be estimated using various methods; here, we focus on a method using line-depth ratios (LDRs). This method combines low- and high-excitation lines and makes use of relations between LDRs of these line pairs and the effective temperature. It has an advantage, for example, of being minimally affected by interstellar reddening, which changes stellar colours. We report 81 relations between LDRs and effective temperature established with high-resolution, λ/Δλ ∼ 28 000, spectra of nine G- to M-type giants in the Y and J bands. Our analysis gives the first comprehensive set of LDR relations for this wavelength range. The combination of all these relations can be used to determine the effective temperatures of stars that have 3700 < Teff < 5400 K and -0.5 < [Fe/H] < +0.3 dex, to a precision of ±10 K in the best cases.

  5. Temperature drives abundance fluctuations, but spatial dynamics is constrained by landscape configuration: Implications for climate-driven range shift in a butterfly.

    Science.gov (United States)

    Fourcade, Yoan; Ranius, Thomas; Öckinger, Erik

    2017-10-01

    Prediction of species distributions in an altered climate requires knowledge on how global- and local-scale factors interact to limit their current distributions. Such knowledge can be gained through studies of spatial population dynamics at climatic range margins. Here, using a butterfly (Pyrgus armoricanus) as model species, we first predicted based on species distribution modelling that its climatically suitable habitats currently extend north of its realized range. Projecting the model into scenarios of future climate, we showed that the distribution of climatically suitable habitats may shift northward by an additional 400 km in the future. Second, we used a 13-year monitoring dataset including the majority of all habitat patches at the species northern range margin to assess the synergetic impact of temperature fluctuations and spatial distribution of habitat, microclimatic conditions and habitat quality, on abundance and colonization-extinction dynamics. The fluctuation in abundance between years was almost entirely determined by the variation in temperature during the species larval development. In contrast, colonization and extinction dynamics were better explained by patch area, between-patch connectivity and host plant density. This suggests that the response of the species to future climate change may be limited by future land use and how its host plants respond to climate change. It is, thus, probable that dispersal limitation will prevent P. armoricanus from reaching its potential future distribution. We argue that models of range dynamics should consider the factors influencing metapopulation dynamics, especially at the range edges, and not only broad-scale climate. It includes factors acting at the scale of habitat patches such as habitat quality and microclimate and landscape-scale factors such as the spatial configuration of potentially suitable patches. Knowledge of population dynamics under various environmental conditions, and the

  6. Concentration and temperature dependence of short-range order in Ni-Ta solid solution using X-ray diffraction method

    International Nuclear Information System (INIS)

    Khwaja, F.A.; Alam, A.

    1980-09-01

    Diffuse X-ray scattering investigations about the existence of short-range order (SRO) have been carried out in the Ni-Ta system for different concentrations and annealing temperatures. It is observed that the values of the SRO parameters for the first co-ordination shell have anomalously large negative values for all the samples studied. These values of the α 1 depend upon the annealing temperatures and the concentration of Ta atoms in the Ni-Ta system. The results of the theoretical predictions of the ordering potential obtained using the formulae of the electronic theory of SRO, confirm the existence of very strong attractive correlation between the atoms of the different species in this system. (author)

  7. Wetting process and interfacial characteristic of Sn-3.0Ag-0.5Cu on different substrates at temperatures ranging from 503 K to 673 K

    Science.gov (United States)

    Zang, Likun; Yuan, Zhangfu; Xu, Hongyan; Xu, Bingsheng

    2011-03-01

    Wetting process and interfacial characteristic of Sn-3.0Ag-0.5Cu have been investigated at temperatures ranging from 503 K to 673 K on Cu, Ni, stainless steel and quartz, respectively. The reactive wetting behavior of Sn-3.0Ag-0.5Cu melt alloy on Cu and Ni substrates were investigated. Contact angles decrease as exponential decay and equilibrium contact angles decrease between the solder and Cu, Ni substrates monotonously with the temperature increasing. The configuration of the triple line of Sn-3.0Ag-0.5Cu/Cu is discussed by the description of equilibrium. The calculated results based on experimental values of tension balances along each of the three interfaces at this final state show good agreement with theoretical analysis. Intermetallics of the Sn-3.0Ag-0.5Cu/Ni interface are identified as (Cu, Ni) 6Sn 5 adjacent to the solder and Ni 3Sn 4 adjacent to the Ni substrate, respectively. The contact angles between Sn-3.0Ag-0.5Cu and quartz, stainless steel substrates were measured to be greater than 90°, which means non-wetting, in the temperature range from 503 K to 673 K. Liquid-solid interfacial energy between the solder and different substrates are obtained based on the surface tension of molten solder and equilibrium contact angles at different temperatures. These results are of practical interest for composite lead-free solders preparations and joining of Sn-3.0Ag-0.5Cu to various substrates.

  8. Elastic oscillation damping and magnetic susceptibility in Y19Fe81 spin glass in the temperature range 70-300 K

    International Nuclear Information System (INIS)

    Zolotukhin, I.V.; Balalaev, S.Yu.

    1990-01-01

    Relaxation properties of Y 19 Fe 81 spin glass (SG) were investigated by means of internal friction(IF). Relaxation process resulting from transition to SG state was determined at sound range frequencies in amorphous alloy. On the basis of the obtained results concerning IF and magnetic susceptibility it follows, that relaxation of certain part of cluster magnetic moments lies within 10 -5 -10 -3 s limits with 0.11±0.06 eV activation energy. IF technique is shown to be used for investigation into relaxation properties, in particular, for acquisition of data on temperature of transition to SG' state

  9. On the effect of the structural properties of polyethylene on the DC conductivity in the temperature range from 40° C to -80° C

    DEFF Research Database (Denmark)

    Khalil, M. S; Henk, Peter O; Henriksen, Mogens

    1990-01-01

    Measurements of the flowing current under the effect of DC fields were conducted using relatively thick samples (1.8 mm) of three different materials: plain low density polyethylene (LDPE), crosslinked polyethylene (XLPE), and 1-wt% TiO2 doped LDPE. The measurements were performed over a range...... of temperatures from 40°C to 80°C and at electric fields as high as 3×105 V/cm. Results indicate that the observed DC conductive characteristics are different for the three materials. Those differences are attributed to the differences of the chemical and morphological structures of the materials used. Scanning...

  10. Effect of precipitation condition, prestrain and temperature on the fatigue behaviour of wrought nickel-based superalloys in the VHCF range

    Energy Technology Data Exchange (ETDEWEB)

    Stoecker, Christian, E-mail: christian.stoecker@uni-siegen.de [Fakultaet 4, Institut fuer Werkstofftechnik, Universitaet Siegen, Paul-Bonatz-Strasse 9-11, Siegen 57068 (Germany); Zimmermann, Martina; Christ, Hans-Juergen [Fakultaet 4, Institut fuer Werkstofftechnik, Universitaet Siegen, Paul-Bonatz-Strasse 9-11, Siegen 57068 (Germany)

    2011-08-15

    The influence of a monotonic predeformation at room temperature on the very high cycle fatigue (VHCF) behaviour was studied in polycrystalline nickel-based superalloys (Nimonic 75 and Nimonic 80A) in three characteristic precipitation conditions (precipitation-free, peak-aged and overaged) after various degrees of predeformation. Isothermal fatigue tests were executed at temperatures up to 800 deg. C. In the intermediate temperature range (400-600 deg. C) the effect of predeformation becomes weaker with increasing temperature. This can be partially explained by the beginning of recovery. However, additional effects not related to the strain-hardened microstructure play a role, such as the formation of oxide layers and the decrease in notch sensitivity. The latter effect is important because of the surface roughening resulting from prestraining. Even for the overaged condition, 4% predeformation led to a higher VHCF fatigue resistance at 600 deg. C, due to the relatively stable recovered dislocation arrangement. Isothermal cyclic deformation at 800 deg. C revealed a pronounced decrease in cyclic lifetime for all precipitation conditions with or without a mechanical prehistory. Transmission electron microscopy was carried out in order to characterize the influence of the microstructure, the resulting dislocation slip behaviour and the relevant dislocation/particle interaction mechanisms on the VHCF behaviour. Furthermore, scanning electron microscopy observations revealed that all precipitation conditions show, independent of their predeformation condition, a transition from transgranular (room temperature to 600 deg. C) to intergranular (600-800 deg. C) microfatigue crack formation in the emerging oxide layers at the surface after VHCF tests.

  11. Effect of precipitation condition, prestrain and temperature on the fatigue behaviour of wrought nickel-based superalloys in the VHCF range

    International Nuclear Information System (INIS)

    Stoecker, Christian; Zimmermann, Martina; Christ, Hans-Juergen

    2011-01-01

    The influence of a monotonic predeformation at room temperature on the very high cycle fatigue (VHCF) behaviour was studied in polycrystalline nickel-based superalloys (Nimonic 75 and Nimonic 80A) in three characteristic precipitation conditions (precipitation-free, peak-aged and overaged) after various degrees of predeformation. Isothermal fatigue tests were executed at temperatures up to 800 deg. C. In the intermediate temperature range (400-600 deg. C) the effect of predeformation becomes weaker with increasing temperature. This can be partially explained by the beginning of recovery. However, additional effects not related to the strain-hardened microstructure play a role, such as the formation of oxide layers and the decrease in notch sensitivity. The latter effect is important because of the surface roughening resulting from prestraining. Even for the overaged condition, 4% predeformation led to a higher VHCF fatigue resistance at 600 deg. C, due to the relatively stable recovered dislocation arrangement. Isothermal cyclic deformation at 800 deg. C revealed a pronounced decrease in cyclic lifetime for all precipitation conditions with or without a mechanical prehistory. Transmission electron microscopy was carried out in order to characterize the influence of the microstructure, the resulting dislocation slip behaviour and the relevant dislocation/particle interaction mechanisms on the VHCF behaviour. Furthermore, scanning electron microscopy observations revealed that all precipitation conditions show, independent of their predeformation condition, a transition from transgranular (room temperature to 600 deg. C) to intergranular (600-800 deg. C) microfatigue crack formation in the emerging oxide layers at the surface after VHCF tests.

  12. On the formation of the L-centre in silicon during heat treatment in the temperature range 205-285 deg. C

    International Nuclear Information System (INIS)

    Mikelsen, M; Monakhov, E V; Avset, B S; Svensson, B G

    2006-01-01

    Annealing kinetics of electron-irradiation induced defects in n-type diffusion oxygenated float-zone silicon has been studied in the temperature-range 205-285 deg. C. Previous deep level transient spectroscopy (DLTS) reports have established that an observed shift in the positions of two peaks related to the divacancy (V 2 ), is due to the annealing of the divacancy and the formation of the divacancy-oxygen complex (V 2 O). In parallel to this transformation from V 2 to V 2 O, a new defect of unknown identity, the so-called L-centre, forms with a level located at 0.36 eV below the conduction band edge. The L-level has a first order formation-kinetics in the temperature region studied; at 245-285 deg. C the formation rate is very similar to the annealing rate of V 2 , while at lower temperatures the formation rate becomes lower with a relative difference by a factor two at 205 deg. C. The Arrhenius plot for the L-level formation rate is not a straight line, indicating that the formation is controlled by at least two different processes. Kinetic modelling shows that the experimental data can be reproduced by a sequence of defect dissociation and migration, where the former limits at low temperatures (activation energy ∼1.75 eV) and the latter at high temperatures (E a ∼1.0 eV). Based on these results and other findings, the identity of the L-centre is discussed

  13. Titanium carbide nanocube core induced interfacial growth of crystalline polypyrrole/polyvinyl alcohol lamellar shell for wide-temperature range supercapacitors

    Science.gov (United States)

    Weng, Yu-Ting; Pan, Hsiao-An; Wu, Nae-Lih; Chen, Geroge Zheng

    2015-01-01

    This is the first investigation on electrically conducting polymers-based supercapacitor electrodes over a wide temperature range, from -18 °C to 60 °C. A high-performance supercapacitor electrode material consisting of TiC nanocube core and conformal crystalline polypyrrole (PPy)/poly-vinyl-alcohol (PVA) lamellar shell has been synthesized by heterogeneous nucleation-induced interfacial crystallization. PPy is induced to crystallize on the negatively charged TiC nanocube surfaces via strong interfacial interactions. In this organic-inorganic hybrid nanocomposite, the long chain PVA enables enhanced cycle life due to improved mechanical properties, and the TiC nanocube not only contributes to electron conduction, but also dictates the PPy morphology/crystallinity for maximizing the charging-discharging performance. The crystalline PPy/PAV layer on the TiC nanocube offers unprecedented high capacity (>350 F g-1-PPy at 300 mV s-1 with ΔV = 1.6 V) and cycling stability in a temperature range from -18 °C to 60 °C. The presented hybrid-filler and interfacial crystallization strategies can be applied to the exploration of new-generation high-power conducting polymer-based supercapacitor materials.

  14. A compilation of correlation parameters for predicting the enthalpy and thermal conductivity of solid foods within the temperature range of -40 C to +40 C

    Energy Technology Data Exchange (ETDEWEB)

    Amos, N.D. [Comvita New Zealand Limited, Private Bag 1, Te Puke 3153 (New Zealand); Willix, J.; North, M.F. [AgResearch Limited, MIRINZ Centre, Ruakura Campus, East Street, Private Bag 3123, Hamilton (New Zealand); Chadderton, T. [Crop and Food Research Ltd, PO Box 5114, Nelson (New Zealand)

    2008-11-15

    This paper presents thermal conductivity data for 40 foods, enthalpy data for 58 foods and density data for nine foods, along with the compositions of the foods. Measurements cover a range of solid food types (including meats, fats, offal, fish, dairy products and horticultural products). Some measurements reported are for foods that have never before been studied, others have been published elsewhere, but are included here for convenience. Thermal conductivity was measured using a guarded hot-plate apparatus, enthalpy using an adiabatic calorimeter and density using a water displacement meter. Thermal conductivity and enthalpy values were measured within the temperature range of -40 C to +40 C. (author) [French] Cette publication presente des donnes sur la conductivite thermique, l'enthalpie et la densite respectivement de 40, 58 et 9 produits alimentaires, ainsi que leurs compositions. Les mesures couvrent une variete de types de produits alimentaires (viande, matieres grasses, abats, poisson, produits laitiers, produits horticoles). Certaines sont rapportees pour des produits qui n 'ant jamais ete etudie auparavant, d'autres ant ete publie ailleurs mais sont aussi inclues pour plus de commodite. La conductivite thermique a ete mesure avec un appareil a plaque electrique protegee, l'enthalpie avec un calorimetre adiabatique et la densite avec un appareil mesurant Ie deplacement d'eau. La conductivite thermique et l'enthalpie ont ete toutes les mesures pour une fourchette de temperatures allant de -40 C a 40 C. (orig.)

  15. Direct measurements of methoxy removal rate constants for collisions with CH4, Ar, N2, Xe, and CF4 in the temperature range 673--973K

    International Nuclear Information System (INIS)

    Wantuck, P.J.; Oldenborg, R.C.; Baugchum, S.L.; Winn, K.R.

    1988-01-01

    Removal rate constants for CH 3 O by CH 4 , Ar, N 2 , Xe, and CF 4 were measured over a 400K temperature range using a laser photolysis/laser-induced fluorescence technique. Rapid methoxy removal rates are observed for the non-reactive collision partners (Ar, N 2 , Xe, and CF 4 ) at elevated temperatures showing that the dissociation and isomerization channels for CH 3 O are indeed important. The total removal rate constant (reaction /plus/ dissociation and/or isomerization) for CH 4 exhibits a linear dependence on temperature and has a removal rate constant, k/sub r/ /equals/ (1.2 +- 0.6) /times/ 10/sup /minus/8/exp[(/minus/101070 +- 350)/T]cm 3 molecule/sup /minus/1/s/sup /minus/1/. Assuming that the removal rate constant due to dissociation and/or isomerization are similar for CH 4 and CF 4 , the reaction rate constant for CH 3 O /plus/ CH 4 is equal to (1.7 +- 1.0) /times/ 10/sup /minus/10/exp[(/minus/7480 +- 1100)/T]cm 3 molecule/sup /minus/1/s/sup /minus/1/. 7 refs., 4 figs

  16. The stress corrosion cracking of heavily sensitized type 316 stainless steel in water in the temperature range 50-100oC

    International Nuclear Information System (INIS)

    Congleton, J.; Sui, G.

    1992-01-01

    The susceptibility to stress corrosion cracking of a Type 316 stainless steel tubing material which had been sensitized in a steam generating rig operated at temperatures from 502 to 533 o C was assessed using the slow strain rate technique. The experiments were performed in de-aerated and in oxygenated water with and without chloride additions and in the temperature range 50-100 o C. The material was susceptible to stress corrosion cracking and to mechanically induced cracking during dynamic straining. Susceptibility to stress corrosion cracking increased with increasing temperature and with increasing oxygen and chloride contents. Cracking occurred with greater than 200 ppb oxygen present even when the chloride content was less than 5 ppb. The maximum allowable oxygen content decreased further when the chloride content was increased. The maximum chloride content for immunity to stress corrosion cracking was 5 ppm even when less than 5 ppb oxygen was present in the water. The severe susceptibility of the material was caused by the complicated metallurgical state of the inner tube surface, but cracking could be prevented by appropriate potentiostatic control. (author)

  17. A 1 kW-class multi-stage heat-driven thermoacoustic cryocooler system operating at liquefied natural gas temperature range

    Science.gov (United States)

    Zhang, L. M.; Hu, J. Y.; Wu, Z. H.; Luo, E. C.; Xu, J. Y.; Bi, T. J.

    2015-07-01

    This article introduces a multi-stage heat-driven thermoacoustic cryocooler capable of reaching cooling capacity about 1 kW at liquefied natural gas temperature range without any moving mechanical parts. The cooling system consists of an acoustically resonant double-acing traveling wave thermoacoustic heat engine and three identical pulse tube coolers. Unlike other traditional traveling wave thermoacoustic heat engines, the acoustically resonant double-acting thermoacoustic heat engine is a closed-loop configuration consists of three identical thermoacoustic conversion units. Each pulse tube cooler is bypass driven by one thermoacoustic heat engine unit. The device is acoustically completely symmetric and therefore "self-matching" for efficient traveling-wave thermoacoustic conversion. In the experiments, with 7 MPa helium gas as working gas, when the heating temperature reaches 918 K, total cooling capacity of 0.88 kW at 110 K is obtained with a resonant frequency of about 55 Hz. When the heating temperature is 903 K, a maximum total cooling capacity at 130 K of 1.20 kW is achieved, with a thermal-to-cold exergy efficiency of 8%. Compared to previously developed heat-driven thermoacoustic cryocoolers, this device has higher thermal efficiency and higher power density. It shows a good prospect of application in the field of natural gas liquefaction and recondensation.

  18. Thermal Annealing to Modulate the Shape Memory Behavior of a Biobased and Biocompatible Triblock Copolymer Scaffold in the Human Body Temperature Range.

    Science.gov (United States)

    Merlettini, Andrea; Gigli, Matteo; Ramella, Martina; Gualandi, Chiara; Soccio, Michelina; Boccafoschi, Francesca; Munari, Andrea; Lotti, Nadia; Focarete, Maria Letizia

    2017-08-14

    A biodegradable and biocompatible electrospun scaffold with shape memory behavior in the physiological temperature range is here presented. It was obtained starting from a specifically designed, biobased PLLA-based triblock copolymer, where the central block is poly(propylene azelate-co-propylene sebacate) (P(PAz60PSeb40)) random copolymer. Shape memory properties are determined by the contemporary presence of the low melting crystals of the P(PAz60PSeb40) block, acting as switching segment, and of the high melting crystal phase of PLLA blocks, acting as physical network. It is demonstrated that a straightforward annealing process applied to the crystal phase of the switching element gives the possibility to tune the shape recovery temperature from about 25 to 50 °C, without the need of varying the copolymer's chemical structure. The thermal annealing approach here presented can be thus considered a powerful strategy for "ad hoc" programming the same material for applications requiring different recovery temperatures. Fibroblast culture experiments demonstrated scaffold biocompatibility.

  19. Recent and historical range shifts of two canopy-forming seaweeds in North Spain and the link with trends in sea surface temperature

    Science.gov (United States)

    Duarte, Linney; Viejo, Rosa M.; Martínez, Brezo; deCastro, Maite; Gómez-Gesteira, Moncho; Gallardo, Tomás

    2013-08-01

    Geographical range shifts of two canopy-forming seaweeds, Himanthalia elongata (L.) S.F. Gray and Fucus serratus L. were investigated at their southern range boundary in Northern Spain from the end of nineteenth century to 2009. Given the good dispersal abilities of H. elongata and its short life-span, we hypothesize that this species will track environmental changes at a faster rate than the perennial and short-distance disperser F. serratus. Our results show a continuous and drastic westward retraction of H. elongata, which has nowadays virtually vanished in Northern Spain, whereas F. serratus is still found in the westernmost area. Despite this, the first species is still relatively abundant in the Iberian Peninsula, whereas the presence of the latter is scattered and reduced. Overall, range shifts fit with the warming trend in sea surface temperature (SST), whereas it is unlikely that increases in grazing pressure or coastal pollution have driven the observed changes, particularly the rapid trend in recent years. Differences in species traits are linked to range dynamics. The higher persistence of F. serratus at eastern shores may thus be related to its longer life span and its greater thermal tolerance. The presence of sporadic populations of H. elongata outside the zone of continuous distribution can be attributed to long-distance dispersal events during cold pulses. Relict populations in isolated and estuarine locations were left behind in the contracting range margins, particularly for F. serratus. In Northern Spain, the westward retreat of large canopy-forming algae seems to be a general phenomenon, involving other species such as kelps. Therefore, an evident reorganization of coastal assemblages is expected, though the temporal extent of changes and the consequences for ecosystem services need to be evaluated.

  20. Viscoplastic behavior of zirconium alloys in the temperatures range 20 deg C - 400 deg C: characterization and modeling of strain ageing phenomena

    International Nuclear Information System (INIS)

    Graff, St.

    2006-10-01

    The anomalous strain rate sensitivity of zirconium alloys over the temperatures range 20-600 C has been widely reported in the literature. This unconventional behavior is related to the existence of strain ageing phenomenon which results from the combined action of thermally activated diffusion of foreign atoms to and along dislocation cores and the long range of dislocations interactions. The important role of interstitial and substitutional atoms in zirconium alloys, responsible for strain ageing and the lack of information about the domain where strain ageing is active have not been yet adequately characterized because of the multiplicity of alloying elements and chemical impurities. The aim of this work is to characterize experimentally the range of temperatures and strain rates where strain ageing is active on the macroscopic and mesoscopic scales. We propose also a predictive approach of the strain ageing effects, using the macroscopic strain ageing model suggested by McCormick (McCormick, 1988; Zhang et al., 2000). Specific zirconium alloys were elaborated starting from a crystal bar of zirconium with 2.2 wt% hafnium and very low oxygen content (80 wt ppm), called ZrHf. Another substitutional atom was added to the solid solution under the form of 1 wt% niobium. Some zirconium alloys were doped with oxygen, others were not. All of them were characterized by various mechanical tests (standard tensile tests, tensile tests with strain rate changes, relaxation tests with unloading). The experimental results were compared with those for the standard oxygen doped zirconium alloy (1300 wt ppm) studied by Pujol (Pujol, 1994) and called Zr702. The following experimental evidences of the age-hardening phenomena were collected and then modeled: 1) low and/or negative strain rate sensitivity around 200-300 C, 2) creep arrest at 200 C, 3) relaxation arrest at 200 C and 300 C, 4) plastic strain heterogeneities observed in laser extensometry on the millimeter scale

  1. Viscoplastic behavior of zirconium alloys in the temperatures range 20 deg C - 400 deg C: characterization and modeling of strain ageing phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Graff, St

    2006-10-15

    The anomalous strain rate sensitivity of zirconium alloys over the temperatures range 20-600 C has been widely reported in the literature. This unconventional behavior is related to the existence of strain ageing phenomenon which results from the combined action of thermally activated diffusion of foreign atoms to and along dislocation cores and the long range of dislocations interactions. The important role of interstitial and substitutional atoms in zirconium alloys, responsible for strain ageing and the lack of information about the domain where strain ageing is active have not been yet adequately characterized because of the multiplicity of alloying elements and chemical impurities. The aim of this work is to characterize experimentally the range of temperatures and strain rates where strain ageing is active on the macroscopic and mesoscopic scales. We propose also a predictive approach of the strain ageing effects, using the macroscopic strain ageing model suggested by McCormick (McCormick, 1988; Zhang et al., 2000). Specific zirconium alloys were elaborated starting from a crystal bar of zirconium with 2.2 wt% hafnium and very low oxygen content (80 wt ppm), called ZrHf. Another substitutional atom was added to the solid solution under the form of 1 wt% niobium. Some zirconium alloys were doped with oxygen, others were not. All of them were characterized by various mechanical tests (standard tensile tests, tensile tests with strain rate changes, relaxation tests with unloading). The experimental results were compared with those for the standard oxygen doped zirconium alloy (1300 wt ppm) studied by Pujol (Pujol, 1994) and called Zr702. The following experimental evidences of the age-hardening phenomena were collected and then modeled: 1) low and/or negative strain rate sensitivity around 200-300 C, 2) creep arrest at 200 C, 3) relaxation arrest at 200 C and 300 C, 4) plastic strain heterogeneities observed in laser extensometry on the millimeter scale

  2. Autumn–winter minimum temperature changes in the southern Sikhote-Alin mountain range of northeastern Asia since 1529 AD

    Directory of Open Access Journals (Sweden)

    O. N. Ukhvatkina

    2018-01-01

    Full Text Available The aim of our research was to reconstruct climatic parameters (for the first time for the Sikhote-Alin mountain range and to compare them with global climate fluctuations. As a result, we have found that one of the most important limiting factors for the study area is the minimum temperatures of the previous autumn–winter season (August–December, and this finding perfectly conforms to that in other territories. We reconstructed the previous August–December minimum temperature for 485 years, from 1529 to 2014. We found 12 cold periods (1535–1540, 1550–1555, 1643–1649, 1659–1667, 1675–1689, 1722–1735, 1791–1803, 1807–1818, 1822–1827, 1836–1852, 1868–1887, 1911–1925 and seven warm periods (1560–1585, 1600–1610, 1614–1618, 1738–1743, 1756–1759, 1776–1781, 1944–2014. These periods correlate well with reconstructed data for the Northern Hemisphere and the neighboring territories of China and Japan. Our reconstruction has 3-, 9-, 20-, and 200-year periods, which may be in line with high-frequency fluctuations in El Niño–Southern Oscillation (ENSO, the short-term solar cycle, Pacific Decadal Oscillation (PDO fluctuations, and the 200-year solar activity cycle, respectively. We suppose that the temperature of the North Pacific, expressed by the PDO may make a major contribution to regional climate variations. We also assume that the regional climatic response to solar activity becomes apparent in the temperature changes in the northern part of Pacific Ocean and corresponds to cold periods during the solar minimum. These comparisons show that our climatic reconstruction based on tree ring chronology for this area may potentially provide a proxy record for long-term, large-scale past temperature patterns for northeastern Asia. The reconstruction reflects the global traits and local variations in the climatic processes of the southern territory of the Russian Far East for more than the past 450 years.

  3. Constraining the Depth of a Martian Magma Ocean through Metal-Silicate Partitioning Experiments: The Role of Different Datasets and the Range of Pressure and Temperature Conditions

    Science.gov (United States)

    Righter, K.; Chabot, N.L.

    2009-01-01

    Mars accretion is known to be fast compared to Earth. Basaltic samples provide a probe into the interior and allow reconstruction of siderophile element contents of the mantle. These estimates can be used to estimate conditions of core formation, as for Earth. Although many assume that Mars went through a magma ocean stage, and possibly even complete melting, the siderophile element content of Mars mantle is consistent with relatively low pressure and temperature (PT) conditions, implying only shallow melting, near 7 GPa and 2073 K. This is a pressure range where some have proposed a change in siderophile element partitioning behavior. We will examine the databases used for parameterization and split them into a low and higher pressure regime to see if the methods used to reach this conclusion agree for the two sets of data.

  4. Improvement of magnetoresistance over a wide temperature range in La2/3Sr1/3MnO3/polymer composites

    International Nuclear Information System (INIS)

    Yan Chunhua; Huang Yunhui; Chen Xing; Liao Chunsheng; Wang Zheming

    2002-01-01

    Polymer-embedded La 2/3 Sr 1/3 MnO 3 (LSMO) composites, (LSMO) 1-x (PPP) x (PPP is polyparaphenylene, and x is the weight fraction of PPP), were prepared by mixing pre-prepared LSMO and PPP powders. Thermogravimetric analysis, x-ray diffraction, and infrared spectra show that the composites are stable when calcined at 400 0 C. Significant enhancement in the magnetoresistance (MR) effect over a wide temperature range is observed for the composites compared with the parent LSMO. The MR enhancement reaches its maximum at x=0.2. The magnetotransport is mainly attributed to intergrain spin-polarized tunnelling. We argue that the introduction of PPP gives rise to magnetic disorder and hence an enhanced tunnelling effect, which is responsible for the MR enhancement. (author)

  5. Half-metallic compensated ferrimagnetism with a tunable compensation point over a wide temperature range in the Mn-Fe-V-Al Heusler system

    Directory of Open Access Journals (Sweden)

    Rolf Stinshoff

    2017-10-01

    Full Text Available The cubic Heusler compound Mn1.5FeV0.5Al with the L21 Heusler structure is the first fully compensated half-metallic ferrimagnet with 24 valence electrons. The ferrimagnetic state can be tuned by changing the composition such that the compensation point appears at finite temperatures ranging from 0 K up to 226 K, while retaining half-metallicity in the system. In this paper, the structural, magnetic and transport properties of the Mn-Fe-V-Al system are discussed. Magnetic reversal and a change of sign of the anomalous Hall effect were observed at the compensation point, which gives rise to a sublattice spin-crossing. These materials present new possibilities for potential spintronic devices because of their advantageous properties such as imperceptibility to external fields, lower power consumption and ultrafast switching in the THz region.

  6. Early changes of cortical blood flow, brain temperature and electrical activity after whole-body irradiation of the monkey (Macaca fascicularis) (dose range: 3-20 Gy)

    International Nuclear Information System (INIS)

    Court, L.; Gourmelon, P.; Mestries, J.C.

    1987-02-01

    A polyparametric investigation was carried out on 31 monkeys chronically wearing bioinstrumentation allowing to get and process simultaneously local brain blood flow, cerebral temperature, and energies in various frequency bands of the brain electrical activity. This method, which supplied data during several consecutive days, made it possible to study both the biological rhythms at the level of the various parameters, and their fast variations. The effects of whole-body gamma or neutron-gamma irradiation were studied in the 3-20 Gy dose range. Immediate changes after exposure demonstrated different radiosensitivities at the level of the rhythms of the various parameters, and/or their recovery, as well as dose-effect relationships [fr

  7. Hot corrosion of Co-Cr, Co-Cr-Al, and Ni-Cr alloys in the temperature range of 700-750 deg C

    Science.gov (United States)

    Chiang, K. T.; Meier, G. H.

    1980-01-01

    The effect of SO3 pressure in the gas phase on the Na2SO4 induced hot corrosion of Co-Cr, Ni-Cr, and Co-Cr-Al alloys was studied in the temperature range 700 to 750 C. The degradation of the Co-Cr and Ni-Cr alloys was found to be associated with the formation of liquid mixed sulfates (CoSO4-Na2SO4 or NiSO4-Na2SO4) which provided a selective dissolution of the Co or Ni and a subsequent sulfidation oxidation mode of attack which prevented the maintenance of a protective Cr2O3 film. A clear mechanism was not developed for the degradation of Co-Cr-Al alloys. A pitting corrosion morphology was induced by a number of different mechanisms.

  8. Quantum mechanical free energy profiles with post-quantization restraints: Binding free energy of the water dimer over a broad range of temperatures

    Science.gov (United States)

    Bishop, Kevin P.; Roy, Pierre-Nicholas

    2018-03-01

    Free energy calculations are a crucial part of understanding chemical systems but are often computationally expensive for all but the simplest of systems. Various enhanced sampling techniques have been developed to improve the efficiency of these calculations in numerical simulations. However, the majority of these approaches have been applied using classical molecular dynamics. There are many situations where nuclear quantum effects impact the system of interest and a classical description fails to capture these details. In this work, path integral molecular dynamics has been used in conjunction with umbrella sampling, and it has been observed that correct results are only obtained when the umbrella sampling potential is applied to a single path integral bead post quantization. This method has been validated against a Lennard-Jones benchmark system before being applied to the more complicated water dimer system over a broad range of temperatures. Free energy profiles are obtained, and these are utilized in the calculation of the second virial coefficient as well as the change in free energy from the separated water monomers to the dimer. Comparisons to experimental and ground state calculation values from the literature are made for the second virial coefficient at higher temperature and the dissociation energy of the dimer in the ground state.

  9. Self-welding evaluation of type 304 and A286 stainless steel in the temperature range 800/sup 0/-1140/sup 0/F in flowing sodium

    Energy Technology Data Exchange (ETDEWEB)

    Chang, J.Y.; Flagella, P.N.; Schrock, S.L.

    1976-01-01

    This paper covers two material combinations, Type 304 SS vs Type 304 SS and Type 304 SS vs A286, tested at temperatures from 800 to 1140/sup 0/F for time periods up to six months in flowing sodium. Contact stresses ranged from 2 to 30 ksi on contact areas for 0.63 to 1.00 in./sup 2/. Tests were performed in either tensile or shear modes on the flat-on-flat samples. Surface morphologies of the sample before and after the test were presented. Self-welding of Type 304 SS was significant at temperatures above 1080/sup 0/F while no self-welding was detected at 800/sup 0/F. Sliding friction coefficient (..mu..) data for a Type 304 SS couple at 800/sup 0/F under compressive stresses from 2000 to 30,000 psi in sodium could be correlated quite accurately by W/sigma = 0.08e/sup 9..mu../, where W is the waviness height in microinches and sigma is the compressive stress in kilo-pound per square inch. One self-weld couple of Type 304 SS/Type 304 SS exposed at 1080/sup 0/F for 3 months was not separated but rather removed intact from the test apparatus and examined in cross-section. Scanning electron micrographs of the contacted area revealed that portions of the original interface were no longer discernible. (auth)

  10. Quantum mechanical free energy profiles with post-quantization restraints: Binding free energy of the water dimer over a broad range of temperatures.

    Science.gov (United States)

    Bishop, Kevin P; Roy, Pierre-Nicholas

    2018-03-14

    Free energy calculations are a crucial part of understanding chemical systems but are often computationally expensive for all but the simplest of systems. Various enhanced sampling techniques have been developed to improve the efficiency of these calculations in numerical simulations. However, the majority of these approaches have been applied using classical molecular dynamics. There are many situations where nuclear quantum effects impact the system of interest and a classical description fails to capture these details. In this work, path integral molecular dynamics has been used in conjunction with umbrella sampling, and it has been observed that correct results are only obtained when the umbrella sampling potential is applied to a single path integral bead post quantization. This method has been validated against a Lennard-Jones benchmark system before being applied to the more complicated water dimer system over a broad range of temperatures. Free energy profiles are obtained, and these are utilized in the calculation of the second virial coefficient as well as the change in free energy from the separated water monomers to the dimer. Comparisons to experimental and ground state calculation values from the literature are made for the second virial coefficient at higher temperature and the dissociation energy of the dimer in the ground state.

  11. Electron spin resonance studies of Bi1-xScxFeO3 nanoparticulates: Observation of an enhanced spin canting over a large temperature range

    Science.gov (United States)

    Titus, S.; Balakumar, S.; Sakar, M.; Das, J.; Srinivasu, V. V.

    2017-12-01

    Bi1-xScxFeO3 (x = 0.0, 0.1, 0.15, 0.25) nano particles were synthesized by sol gel method. We then probed the spin system in these nano particles using electron spin resonance technique. Our ESR results strongly suggest the scenario of modified spin canted structures. Spin canting parameter Δg/g as a function of temperature for Scandium doped BFO is qualitatively different from undoped BFO. A broad peak is observed for all the Scandium doped BFO samples and an enhanced spin canting over a large temperature range (75-210 K) in the case of x = 0.15 doping. We also showed that the asymmetry parameter and thereby the magneto-crystalline anisotropy in these BSFO nanoparticles show peaks around 230 K for (x = 0.10 and 0.15) and beyond 300 K for x = 0.25 system. Thus, we established that the Sc doping significantly modifies the spin canting and magneto crystalline anisotropy in the BFO system.

  12. Mathematical description of plastic behaviour in tensile tests of austenitic stainless steel AISI 310 in temperature range 293-1173 K

    International Nuclear Information System (INIS)

    Matteazzi, S.; Petrone, G.; Piatti, G.

    1985-01-01

    The predictability of the tensile mechanical behaviour was studied by the authors on the stainless steels outside the range of proportionality by the use of different phenomenological constitutive equations. Some of them, of the type σ = σ(epsilonsub(p)), where σ = true stress and epsilonsub(p) = true plastic strain, involve only one independent variable, whereas others of the type σ = σ(epsilonsub(p),epsilon), where (epsilon) = true strain rate, took into account two dependent variables. The experimental data were obtained from solution annealed AISI 310 steel samples tested at different temperatures between 293 and 1173 K and for two strain rates, 1.2.10 -3 and 2.8.10 -1 s -5 . Analysis of the results showed the good fitting of Ludwigson's law for the equations with one independent variable only, whereas for the equations with two independent variables that of Matteazzi-Petrone-Piatti follows the experimental results very well at room temperature where the rate processes are important. (author)

  13. Thermoeconomic Evaluation of Modular Organic Rankine Cycles for Waste Heat Recovery over a Broad Range of Heat Source Temperatures and Capacities

    Directory of Open Access Journals (Sweden)

    Markus Preißinger

    2017-02-01

    Full Text Available Industrial waste heat recovery by means of an Organic Rankine Cycle (ORC can contribute to the reduction of CO2 emissions from industries. Before market penetration, high efficiency modular concepts have to be developed to achieve appropriate economic value for industrial decision makers. This paper aims to investigate modularly designed ORC systems from a thermoeconomic point of view. The main goal is a recommendation for a suitable chemical class of working fluids, preferable ORC design and a range of heat source temperatures and thermal capacities in which modular ORCs can be economically feasible. For this purpose, a thermoeconomic model has been developed which is based on size and complexity parameters of the ORC components. Special emphasis has been laid on the turbine model. The paper reveals that alkylbenzenes lead to higher exergetic efficiencies compared to alkanes and siloxanes. However, based on the thermoeconomic model, the payback periods of the chemical classes are almost identical. With the ORC design, the developed model and the boundary conditions of this study, hexamethyldisiloxane is a suitable working fluid and leads to a payback period of less than 5 years for a heat source temperature of 400 to 600 °C and a mass flow rate of the gaseous waste heat stream of more than 4 kg/s.

  14. Impact of urbanization and land-use/land-cover change on diurnal temperature range: a case study of tropical urban airshed of India using remote sensing data.

    Science.gov (United States)

    Mohan, Manju; Kandya, Anurag

    2015-02-15

    Diurnal temperature range (DTR) is an important climate change index. Its knowledge is important to a range of issues and themes in earth sciences central to urban climatology and human-environment interactions. The present study investigates the effect of urbanization on the land surface temperature (LST) based DTR. This study presents spatial and temporal variations of satellite based estimates of annually averaged DTR over megacity Delhi, the capital of India, which are shown for a period of 11 years during 2001-2011 and analyzes this with regard to its land-use/land-cover (LU/LC) changes and population growth. Delhi which witnessed massive urbanization in terms of population growth (decadal growth rate of Delhi during 2001-2011 was 20.96%) and major transformations in the LU/LC (built-up area crossed more than 53%) are experiencing severity in its micro and macroclimate. There was a consistent increase in the areas experiencing DTR below 11°C which typically resembled the 'urban class' viz. from 26.4% in the year 2001 to 65.3% in the year 2011 and subsequently the DTR of entire Delhi which was 12.48°C in the year 2001 gradually reduced to 10.34°C in the year 2011, exhibiting a significant decreasing trend. Rapidly urbanizing areas like Rohini, Dwarka, Vasant Kunj, Kaushambi, Khanjhawala Village, IIT, Safdarjung Airport, etc. registered a significant decreasing trend in the DTR. In the background of the converging DTR, which was primarily due to the increase in the minimum temperatures, a grim situation in terms of potentially net increase in the heat-related mortality rate especially for the young children below 15years of age is envisaged for Delhi. Considering the earlier findings that the level of risk of death remained the highest and longest for Delhi, in comparison to megacities like Sao Paulo and London, the study calls for strong and urgent heat island mitigation measures. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Improving the Catalytic Activity of Hyperthermophilic Pyrococcus horikoshii Prolidase for Detoxification of Organophosphorus Nerve Agents over a Broad Range of Temperatures

    Directory of Open Access Journals (Sweden)

    Casey M. Theriot

    2011-01-01

    Full Text Available Prolidases hydrolyze Xaa-Pro dipeptides and can also cleave the P-F and P-O bonds found in organophosphorus (OP compounds, including the nerve agents soman and sarin. Ph1prol (PH0974 has previously been isolated and characterized from Pyrococcus horikoshii and was shown to have higher catalytic activity over a broader pH range, higher affinity for metal, and increased thermostability compared to P. furiosus prolidase, Pfprol (PF1343. To obtain a better enzyme for OP nerve agent decontamination and to investigate the structural factors that may influence protein thermostability and thermoactivity, randomly mutated Ph1prol enzymes were prepared. Four Ph1prol mutants (A195T/G306S-, Y301C/K342N-, E127G/E252D-, and E36V-Ph1prol were isolated which had greater thermostability and improved activity over a broader range of temperatures against Xaa-Pro dipeptides and OP nerve agents compared to wild type Pyrococcus prolidases.

  16. A comparison between rare earth and transition metals working as magnetic materials in an AMR refrigerator in the room temperature range

    International Nuclear Information System (INIS)

    Aprea, C.; Greco, A.; Maiorino, A.; Masselli, C.

    2015-01-01

    This paper describes a two-dimensional (2D) multiphysics model of a packed bed regenerator made of magnetocaloric material. The regenerator operates as a refrigerant for a magnetic refrigerator operating at room temperature on the strength of an active magnetic regenerator (AMR) cycle. The model is able to simulate the thermofluidodynamic behavior of the magnetocaloric material and the magnetocaloric effect of the refrigerant. The model has been validated by means of experimental results. Different magnetic materials have been tested with the model as refrigerants: pure gadolinium, second order phase magnetic transition Pr 0.45 Sr 0.35 MnO 3 and first order phase magnetic transition alloys Gd 5 (Si x Ge 1−x ) 4 , LaFe 11.384 Mn 0.356 Si 1.26 H 1.52 , LaFe 11.05 Co 0.94 Si 1.10 and MnFeP 0.45 As 0.55 . The tests were performed with fixed fluid flow rate (5 l/min), AMR cycle frequency (1.25 Hz) and cold heat exchanger temperature (288 K) while the hot heat exchanger temperature was varied in the range 295–302 K. The results, generated for a magnetic induction which varies from 0 to 1.5 T, are presented in terms of temperature span, refrigeration power and coefficient of performance. From a global point of view (performances and cost), the most promising materials are LaFeSi compounds which are really cheaper than rare earth compounds and they give a performance sufficiently higher than gadolinium. - Graphical abstract: • Active Magnetic Refrigeration (AMR) cycle; • First Order Transition magnetic materials (FOMT); • Second Order Transition magnetic materials (SOMT). - Highlights: • Comparison between different magnetic materials. • 2D model of an Active Magnetic Regenerative refrigeration cycle. • Validation of the model with experimental data. • Gd 5 (Si x Ge 1−x ) 4 is the most performant magnetic material. • The most promising are LaFeSi compounds which are cheaper and they give high performances.

  17. Speed-of-sound measurements in (argon + carbon dioxide) over the temperature range from (275 to 500) K at pressures up to 8 MPa

    International Nuclear Information System (INIS)

    Wegge, Robin; McLinden, Mark O.; Perkins, Richard A.; Richter, Markus; Span, Roland

    2016-01-01

    Highlights: • The speed of sound was measured in (argon + carbon dioxide) mixtures. • Measurements were carried out from T = (275 to 500) K at pressures up to 8 MPa. • Measurements were made with the spherical acoustic resonator at NIST-Boulder. • The vibrational relaxation of pure carbon dioxide led to high sound absorption. • The relative combined expanded uncertainty (k = 2) ranged from (0.042 to 0.056)%. - Abstract: The speed of sound of two (argon + carbon dioxide) mixtures was measured over the temperature range from (275 to 500) K with pressures up to 8 MPa utilizing a spherical acoustic resonator. The compositions of the gravimetrically prepared mixtures were (0.50104 and 0.74981) mole fraction carbon dioxide. The vibrational relaxation of pure carbon dioxide led to high sound absorption, which significantly impeded the sound-speed measurements on carbon dioxide and its mixtures; pre-condensation may have also affected the results for some measurements near the dew line. Thus, in contrast to the standard operating procedure for speed-of-sound measurements with a spherical resonator, non-radial resonances at lower frequencies were taken into account. Still, the data show a comparatively large scatter, and the usual repeatability of this general type of instrument could not be realized with the present measurements. Nonetheless, the average relative combined expanded uncertainty (k = 2) in speed of sound ranged from (0.042 to 0.056)% for both mixtures, with individual state-point uncertainties increasing to 0.1%. These uncertainties are adequate for our intended purpose of evaluating thermodynamic models. The results are compared to a Helmholtz energy equation of state for carbon capture and storage applications; relative deviations of (−0.64 to 0.08)% for the (0.49896 argon + 0.50104 carbon dioxide) mixture, and of (−1.52 to 0.77)% for the (0.25019 argon + 0.74981 carbon dioxide) mixture were observed.

  18. Gender, Age and Season as Modifiers of the Effects of Diurnal Temperature Range on Emergency Room Admissions for Cause-Specific Cardiovascular Disease among the Elderly in Beijing

    Directory of Open Access Journals (Sweden)

    Shan Zheng

    2016-04-01

    Full Text Available Background: Diurnal temperature range (DTR is an important index of climate change and variability. It is also a risk factor affecting human health. However, limited evidence is available to illustrate the effect of DTR modification on cause-specific cardiovascular disease among the elderly. Methods: A semi-parametric generalized additive model (GAM was used to analyze the exposure-effect relationship between DTR and daily emergency room (ER admissions for cause-specific cardiovascular diseases among the elderly from 2009 to 2011 in Beijing. We examined the effects of DTR for stratified groups by gender and age, and examined the effects of DTR in the warm season and cold season for cause-specific cardiovascular diseases. Results: Significant associations were found between DTR and ER admissions for all cardiovascular and cerebrovascular disease among elderly males, while DTR was significantly associated with ER admissions for all cardiovascular disease, ischemic heart disease and cerebrovascular disease among elderly females. People aged 75 years and older were more vulnerable to DTR. DTR caused greater adverse effects on both genders in the warm season, whereas the effect estimates on females were higher in cold season than in warm season. Conclusions: A short-term increase of DTR was significantly associated with ER admissions for cause-specific cardiovascular disease among the elderly in Beijing. Gender, age and season may modify the acute health effect of DTR. Some prevention programs that target the high risk subgroups in the elderly for impending large temperature changes may reduce the impact of DTR on people’s health.

  19. Spin exchange in solutions of TEMPOL in n-octanol and 1-methyl-3-octylimidazolium hexafluorophosphate in the temperature range from 300 to 500 K.

    Science.gov (United States)

    Stösser, Reinhard; Herrmann, Werner; Marx, Ulrich; Brückner, Angelika

    2011-04-14

    Comprehensive examinations of the motional properties (rotational correlation time τ(R)) and the spin exchange ω(SS) of the spin probe TEMPOL have been carried out using ESR spectroscopy in two different solvents. For the first time, the dynamic parameters τ(R) and ω(SS) have been determined simultaneously by simulation of spectra measured at three different ESR frequencies (L-, X-, and Q-band) between 293 and 500 K using a dynamic model based on a stochastic fitting program and, for comparison, two alternative models involving the shift of the hyperfine lines and considering the line broadening due to spin exchange in a wide range of conditions. Possibilities and limits of the used models are shown upon comparing the obtained results of the spin exchange. Moreover, the analysis of the ESR spectra gave evidence for the existence of cage effects that produce re-encounters of the spin probes. This has been done for the activation energies, which have been calculated from the temperature dependence of the rate constants of the spin exchange. From the ratio of the activation energies and the influence of the viscosities on the dynamics of the examined systems in n-octanol and an ionic liquid, conclusions can be drawn for the re-encounter effects in solvent cages. However, in contrast to n-octanol, the dynamics of the spin probe in the ionic liquid depends on specific and anisotropic interactions. The temperature dependence of the Q-band measurements required the development of a novel Q-band cavity.

  20. The association between diurnal temperature range and emergency room admissions for cardiovascular, respiratory, digestive and genitourinary disease among the elderly: a time series study.

    Science.gov (United States)

    Wang, Min-zhen; Zheng, Shan; He, Shi-lin; Li, Bei; Teng, Huai-jin; Wang, Shi-gong; Yin, Ling; Shang, Ke-zheng; Li, Tan-shi

    2013-07-01

    To evaluate the short-term effect of diurnal temperature range (DTR) on emergency room (ER) admissions among elderly adults in Beijing. After controlling the long-time and seasonal trend, weather, air pollution and other confounding factors, a semi-parametric generalized additive model (GAM) was used to analyze the exposure-effect relationship between DTR and daily ER admissions among elderly adults with different lag structures from 2009 to 2011 in Beijing. We examined the effects of DTR for stratified groups by age and gender, and conducted the modifying effect of season on DTR to test the possible interaction. Significant associations were found between DTR and four major causes of daily ER admissions among elderly adults in Beijing. A 1 °C increase in the 8-day moving average of DTR (lag 07) corresponded to an increase of 2.08% (95% CI: 0.88%-3.29%) in respiratory ER admissions and 2.14% (95% CI: 0.71%-3.59%) in digestive ER admissions. A 1 °C increase in the 3-day and 6-day moving average of DTR (lag 02 and lag 05) corresponded to a 0.76% (95% CI: 0.07%-1.46%) increase in cardiovascular ER admissions, and 1.81% (95% CI: 0.21%-3.45%) increase in genitourinary ER admissions, respectively. The people aged 75 years and older were associated more strongly with DTR than the 65-74 age group. The modifying effect of season on DTR was observed and it was various in four causes. This study strengthens the evidence that DTR is an independent risk factor for ER admissions among elderly persons. Some prevention programs that target the elderly and other high risk subgroups for impending large temperature changes may reduce the impact of DTR on people's health. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Calibration of a T-History calorimeter to measure enthalpy curves of phase change materials in the temperature range from 40 to 200 °C

    International Nuclear Information System (INIS)

    Rathgeber, Christoph; Schmit, Henri; Hennemann, Peter; Hiebler, Stefan

    2014-01-01

    Thermal energy storage using phase change materials (PCMs) provides high storage capacities in small temperature ranges. For the design of efficient latent heat storage, the enthalpy curve of a PCM has to be measured with high precision. Measurements are most commonly performed with differential scanning calorimetry (DSC). The T-History method, however, proved to be favourable for the characterization of typical PCMs due to large samples and a measuring procedure close to conditions found in applications. As T-History calorimeters are usually individual constructions, performing a careful calibration procedure is decisive to ensure optimal measuring accuracy. We report in this paper on the calibration of a T-History calorimeter with a working range from 40 to 200 °C that was designed and built at our institute. A three-part procedure, consisting of an indium calibration, a measurement of the specific heat of copper and measurements of three solid–liquid PCMs (stearic acid, dimethyl terephthalate and d-mannitol), was performed and an advanced procedure for the correction of enthalpy curves was developed. When comparing T-History enthalpy curves to literature data and DSC step measurements, good agreement within the uncertainty limits demanded by RAL testing specifications was obtained. Thus, our design of a T-History calorimeter together with the developed calibration procedure provides the measuring accuracy that is required to identify the most suitable PCM for a given application. In addition, the dependence of the enthalpy curve on the sample size can be analysed by comparing results obtained with T-History and DSC and the behaviour of the bulk material in real applications can be predicted. (paper)

  2. Rechargeable Lithium Sulfur (Li-S) Battery with Specific Energy 400 Wh/kg and Operating Temperature Range -60°C to 60°C, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Sion Power is developing a rechargeable lithium sulfur (Li-S) battery with a demonstrated specific energy exceeding 350 Wh/kg and the range of operating temperatures...

  3. Thermodynamic investigation of N,N-dimethylformamide/toluene binary mixtures in the temperature range from 278.15 to 293.15K

    International Nuclear Information System (INIS)

    Tsierkezos, Nikos G.; Filippou, Alexander C.

    2006-01-01

    Densities (ρ), surface tensions (σ), and absolute viscosities (η) of binary mixtures of N,N-dimethylformamide (DMF) with toluene have been measured over the entire composition range at the temperatures (278.15, 283.15, and 293.15)K. The excess molar volumes (V E ), the excess surface tensions (σ E ), the deviations in viscosity (Δη), and the excess free energies of activation of the viscous flow (ΔG* E ) have been calculated. The excess thermodynamic properties V E , σ E , Δη, and ΔG* E were fitted to the Redlich-Kister polynomial equation, and the A k coefficients as well as the standard deviations between the calculated and experimental values have been derived. The surface tension values have been further used to calculate the surface entropy (S S ) and surface enthalpy (H S ) per unit surface area. The lyophobicity (β) and the surface mole fraction (x 2 S ) of the surfactant toluene have been also derived using the extended Langmuir model. The results obtained are discussed from the viewpoint of the existence of interactions between the components in the bulk and the surface

  4. First-principles theory of the temperature and compositional dependence of atomic short-range order in disordered Cu-Pd alloys

    Science.gov (United States)

    Chepulskii, R. V.; Staunton, J. B.; Bruno, Ezio; Ginatempo, B.; Johnson, D. D.

    2002-02-01

    We combine the first-principles, Korringa-Kohn-Rostoker coherent potential approximation based calculations of compositional fluctuations with a statistical mechanical ring approximation to study the temperature (T) and composition (c) dependence of the atomic short-range order (SRO) in disordered, face-centred cubic, Cu-Pd alloys. The fourfold splitting of SRO peaks around the equivalent X(0,1,0) points in reciprocal space is obtained in a wide T-c region. Such splitting is shown to be an ``energy'' effect caused by the absolute minima of the Fourier transform of the effective atomic interactions and related previously to the existence of nested sheets of the disordered alloy's Fermi surface. However, we find that the T dependence of the SRO peak position is mostly an ``entropy'' effect. Both the calculated T and c dependences of the SRO peaks position are in good correspondence with the experimental data. The real-space effective atomic interactions and SRO parameters indicate the tendency for longer-period structures with increasing Pd concentration, as observed.

  5. Elastic and relaxation properties of HTSC-composites BSCCO(2223)+ (0-100)% Ag in the temperature range 5-300 K

    International Nuclear Information System (INIS)

    Pal'-Val', P.P.; Pal'-Val', L.N.; Natsik, V.D.; Kislyak, I.F.; Dotsenko, V.I.

    1996-01-01

    Acoustic and relaxation properties of ceramic composites Bi 1,6 Pb 0,4 Sr 2 Ca 2 Cu 3 O 10+δ -Ag have been studied in a wide range of silver concentrations (0-100%). In the vicinity of 150 K, an absorption peak is found in the temperature spectrum of sound absorption for the samples of BSCCO (2223) ceramics. The peak height changes non-monotonically when adding silver into the ceramics. The peak is found to be of the relaxation nature and activation parameters of the related relaxation process localized on the grain boundaries of the ceramics are determined. Another relaxation absorption peak near 70 K is observed in the BCCO(2223)-Ag samples. The intensity of the peak increases with silver concentration. The correlation revealed between the anomalies in the concentration dependences of the acoustic properties and the width of the superconducting transition shows that the adding of silver into intergrain spaces is to a great extent responsible for the elastic, relaxation and superconducting properties of the composites studied

  6. Phase Change Material Selection for Thermal Energy Storage at High Temperature Range between 210 °C and 270 °C

    Directory of Open Access Journals (Sweden)

    José Miguel Maldonado

    2018-04-01

    Full Text Available The improvement of thermal energy storage systems implemented in solar technologies increases not only their performance but also their dispatchability and competitiveness in the energy market. Latent heat thermal energy storage systems are one of those storing methods. Therefore, the need of finding the best materials for each application becomes an appealing research subject. The main goal of this paper is to find suitable and economically viable materials able to work as phase change material (PCM within the temperature range of 210–270 °C and endure daily loading and unloading processes in a system with Fresnel collector and an organic Rankine cycle (ORC. Twenty-six materials have been tested and characterized in terms of their thermophysical conditions, thermal and cycling stability, and health hazard. Two materials out of the 26 candidates achieved the last stage of the selection process. However, one of the two finalists would require an inert working atmosphere, which would highly increase the cost for the real scale application. This leads to a unique suitable material, solar salt (40 wt % KNO3/60 wt % NaNO3.

  7. X-ray and neutron diffraction study of benzoylacetone in the temperature range 8-300 K: comparison with other cis-enol molecules.

    Science.gov (United States)

    Herbstein; Iversen; Kapon; Larsen; Madsen; Reisner

    1999-10-01

    The crystal structure of benzoylacetone (1-phenyl-1,3-butanedione, C(10)H(10)O(2); P2(1)/c, Z = 4) has been determined at 300, 160 (both Mo Kalpha X-ray diffraction, XRD), 20 (lambda = 1.012 Å neutron diffraction, ND) and 8 K (Ag Kalpha XRD), to which should be added earlier structure determinations at 300 (Mo Kalpha XRD and ND, lambda = 0.983 Å) and 143 K (Mo Kalpha XRD). Cell dimensions have been measured over the temperature range 8-300 K; a first- or second-order phase change does not occur within this range. The atomic displacement parameters have been analyzed using the thermal motion analysis program THMA11. The most marked change in the molecular structure is in the disposition of the methyl group, which has a librational amplitude of approximately 20 degrees at 20 K and is rotationally disordered at 300 K. The lengths of the two C-O bonds in the cis-enol ring do not differ significantly, nor do those of the two C-C bonds, nor do these lengths change between 8 and 300 K. An ND difference synthesis (20 K) shows a single enol hydrogen trough (rather than two half H atoms), approximately centered between the O atoms; analogous results were obtained by XRD (8 K). It is inferred that the enol hydrogen is in a broad, flat-bottomed single-minimum potential well between the O atoms, with a libration amplitude of approximately 0.30 Å at 8 K. These results suggest that at 8 K the cis-enol ring in benzoylacetone has quasi-aromatic character, in agreement with the results of high-level ab initio calculations made for benzoylacetone [Schiøtt et al. (1998). J. Am. Chem. Soc. 120, 12117-12124]. Application [in a related paper by Madsen et al. (1998). J. Am. Chem. Soc. 120, 10040-10045] of multipolar analysis and topological methods to the charge density obtained from the combined lowest temperature X-ray and neutron data provides evidence for an intramolecular hydrogen bond with partly electrostatic and partly covalent character, and large p-delocalization in the cis

  8. In situ measurements of the D1 and D2 Raman band intensities of vitreous and molten silica in the 77-2150 K temperature range

    International Nuclear Information System (INIS)

    Papatheodorou, G N; Kalampounias, A G

    2009-01-01

    In situ quantitative Raman spectra of vitreous and molten silica were measured from LN 2 temperatures up to above melting and used to calculate the intensities of the two 'defect peaks' D 1 and D 2 associated with the corresponding four- and three-membered ring structures. The D 1 intensity decreases with increasing temperature while the D 2 intensity appears to be invariant to temperature. The data are in disagreement with the quenching/fictive temperature experiments and show definitely no abrupt intensity changes at any temperature.

  9. Studies of iron-uptake mechanisms in two bacterial species of the shewanella genus adapted to middle-range (Shewanella putrefaciens) or antarctic (Shewanella gelidimarina) temperatures.

    Science.gov (United States)

    Pakchung, Amalie A H; Soe, Cho Z; Codd, Rachel

    2008-10-01

    Iron(III)-uptake mechanisms in bacteria indigenous to the Antarctic, which is the most Fe-deficient continent on Earth, have not been extensively studied. The cold-adapted, Antarctic bacterium, Shewanella gelidimarina, does not produce detectable levels of the siderophore, putrebactin, in the supernatant of Fe(III)-deprived cultures. This is distinct from the putrebactin-producing bacterium from the same genus, Shewanella putrefaciens, which is adapted to middle-range temperatures. The production of putrebactin by S. putrefaciens is optimal, when the pH value of the medium is 7.0. According to the strong positive response from whole cells in the Chrome Azurol S (CAS) agar diffusion assay, Shewanella gelidimarina appears to produce cell-associated siderophores. In the RP-HPLC trace of an Fe(III)-loaded extract from the cell-associated components of S. gelidimarina cultured in media with [Fe(III)] ca. 0 microM, a peak appears at [MeCN] ca. 77%, which decreases in intensity in a parallel experiment in which [Fe(III)] ca. 5 microM, and is barely detectable in Fe(III)-replete media ([Fe(III)] ca. 20 microM). The Fe(III)-dependence of this peak suggests that the attendant species, which is significantly more hydrophobic than putrebactin (RP-HPLC elution: [MeCN] ca. 14%), is associated with Fe(III)-management in S. gelidimarina. This study highlights the diversity in Fe(III)-uptake mechanisms in Shewanella species adapted to different environmental and thermal niches.

  10. The Start-up of Hybrid, Anaerobic up-flow Sludge Blanket (HUASB under a Range of Mesophiclic and Thermophilic Temperatures

    Directory of Open Access Journals (Sweden)

    S. A. Habeeb

    2011-07-01

    Full Text Available We have examined the effect of gradual increase of the temperature on the performance of anaerobic process of palm oil mill effluent (POME, and sludge granules development. Two hybrid up-flow anaerobic sludge blanket (HUASB reactors R1 and R2 were employed to be run at 27±2 and 37±1°C, respectively. R1 was kept at room temperature for the whole experiment, where the temperature of R2 was increased up to 49ºC (3ºC after every steady-state occurrence. Maximum COD removal of 91% was obtained in R2 at optimum temperature of 46°C, while 84% was recorded in R1. Additional parameters were applied to evaluate the performance of the process, i.e. total suspended solids (TSS, Turbidity, and Color. The imaging of sludge aggregate has revealed the effect of temperature on granulation development during the experiment. Throughout the operation period, it can be seen that the microbial growth rate was significantly affected by temperature. Hence, the use of HUASB reactor could be productively implemented for POME treatment as an efficient system under the mesophilic and thermophilic temperatures.

  11. Porous silicon-VO{sub 2} based hybrids as possible optical temperature sensor: Wavelength-dependent optical switching from visible to near-infrared range

    Energy Technology Data Exchange (ETDEWEB)

    Antunez, E. E.; Salazar-Kuri, U.; Estevez, J. O.; Basurto, M. A.; Agarwal, V., E-mail: vagarwal@uaem.mx [Centro de Investigación en Ingeniería y Ciencias Aplicadas, Instituto de Investigación en Ciencias Básicas y Aplicadas, UAEM, Av. Universidad 1001, Col. Chamilpa, Cuernavaca, Mor. 62209 (Mexico); Campos, J. [Instituto de Energías Renovables, UNAM, Priv. Xochicalco S/N, Temixco, Mor. 62580 (Mexico); Jiménez Sandoval, S. [Laboratorio de Investigación en Materiales, Centro de Investigación y estudios Avanzados del Instituto Politécnico Nacional, Unidad Querétaro, Qro. 76001 (Mexico)

    2015-10-07

    Morphological properties of thermochromic VO{sub 2}—porous silicon based hybrids reveal the growth of well-crystalized nanometer-scale features of VO{sub 2} as compared with typical submicron granular structure obtained in thin films deposited on flat substrates. Structural characterization performed as a function of temperature via grazing incidence X-ray diffraction and micro-Raman demonstrate reversible semiconductor-metal transition of the hybrid, changing from a low-temperature monoclinic VO{sub 2}(M) to a high-temperature tetragonal rutile VO{sub 2}(R) crystalline structure, coupled with a decrease in phase transition temperature. Effective optical response studied in terms of red/blue shift of the reflectance spectra results in a wavelength-dependent optical switching with temperature. As compared to VO{sub 2} film over crystalline silicon substrate, the hybrid structure is found to demonstrate up to 3-fold increase in the change of reflectivity with temperature, an enlarged hysteresis loop and a wider operational window for its potential application as an optical temperature sensor. Such silicon based hybrids represent an exciting class of functional materials to display thermally triggered optical switching culminated by the characteristics of each of the constituent blocks as well as device compatibility with standard integrated circuit technology.

  12. Constitutive modelling of CK45N, AlZnMgCu1.5 and Ti-6Al-4V in a wide range of strain rate and temperature

    Science.gov (United States)

    El-Magd, E.; Treppmann, C.; Korthäuer, M.

    2003-09-01

    Continuous constitutive equations for wide ranges of strain rates and temperatures are gaining increasing importance for adequate simulation of dynamic deformation processes. The flow behaviour of the carbon steel CK45N, the Aluminium Alloy AIZnMgCul.5 and the Titanium Alloy Ti6A14V is studied at different strain rates between 0.001 s^{-1} and 10000 s^{-1} with temperatures varying between 23^{circ}C and 1000^{circ}C at CK45N and Ti6A14V. AIZnMgCul.5 was investigated in a temperature range from 23^{circ}C up to 500^{circ}C. The mechanical behaviour of the three materials over this wide range needs the consideration of different physical deformation mechanisms. In the range of high temperatures and low strain rates stress relaxation due to creep deformation processes are superimposed to the plastic deformation process with a relatively low strain rate sensitivity and temperature dependence. In the range of high strain rates, the damping controlled deformation mechanism is additionally active leading to a high increase of the strain rate sensitivity. In case of steel, a dynamic age hardening mechanism is superimposed causing a stress increase between 300^{circ}C and 600^{circ}C according to strain rate. The correlation between the material parameters and the instability, localisation and damage is studied on the bases of simple models.

  13. CRED Subsurface Temperature Recorder (STR); CNMI, ANA; Long: 145.70271, Lat: 16.33289 (WGS84); Sensor Depth: 3.65m; Data Range: 20070527-20090506.

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    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  14. CRED Subsurface Temperature Recorder (STR); PRIA, PAL; Long: -162.16911, Lat: 05.88415 (WGS84); Sensor Depth: 32.92m; Data Range: 20080331-20100411.

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    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  15. CRED Subsurface Temperature Recorder (STR); NWHI, MAR; Long: -170.53975, Lat: 25.38410 (WGS84); Sensor Depth: 1.52m; Data Range: 20060909-20080919.

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    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  16. CRED Subsurface Temperature Recorder (STR); NWHI, PHR; Long: -175.83974, Lat: 27.78486 (WGS84); Sensor Depth: 22.86m; Data Range: 20081002-20100915.

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    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  17. CRED Subsurface Temperature Recorder (STR); MHI, OAH; Long: -158.21747, Lat: 21.46010 (WGS84); Sensor Depth: 7.32m; Data Range: 20050723-20070305.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  18. CRED Subsurface Temperature Recorder (STR); CNMI, FDP; Long: 144.88580, Lat: 20.54513 (WGS84); Sensor Depth: 12.50m; Data Range: 20070603-20070826.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  19. CRED Subsurface Temperature Recorder (STR); NWHI, PHR; Long: -175.86298, Lat: 27.79097 (WGS84); Sensor Depth: 11.60m; Data Range: 20100520-20100915.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  20. CRED Subsurface Temperature Recorder (STR); MHI, LAN; Long: -156.87525, Lat: 20.74163 (WGS84); Sensor Depth: 11.58m; Data Range: 20081020-20101022.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  1. CRED Subsurface Temperature Recorder (STR); AMSM, TUT; Long: -170.56225, Lat: -14.28368 (WGS84); Sensor Depth: 8.84m; Data Range: 20080223-20090529.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  2. CRED Subsurface Temperature Recorder (STR); MHI, OAH; Long: -158.13684, Lat: 21.35468 (WGS84); Sensor Depth: 17.68m; Data Range: 20090903-20100715.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  3. CRED Subsurface Temperature Recorder (STR); AMSM, OFU; Long: -169.62662, Lat: -14.18175 (WGS84); Sensor Depth: 9.80m; Data Range: 20040207-20060226.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  4. CRED Subsurface Temperature Recorder (STR); NWHI, PHR; Long: -175.77935, Lat: 27.80267 (WGS84); Sensor Depth: 1.52m; Data Range: 20080924-20100914.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  5. CRED Subsurface Temperature Recorder (STR); PRIA, JOH; Long: -169.49963, Lat: 16.75956 (WGS84); Sensor Depth: 7.92m; Data Range: 20060120-20070618.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  6. CRED Subsurface Temperature Recorder (STR); PRIA, WAK; Long: 166.60452, Lat: 19.30868 (WGS84); Sensor Depth: 1.52m; Data Range: 20070505-20090325.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  7. CRED Subsurface Temperature Recorder (STR); CNMI, FDP; Long: 144.90023, Lat: 20.53725 (WGS84); Sensor Depth: 31.70m; Data Range: 20070603-20090428.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  8. CRED Subsurface Temperature Recorder (STR); NWHI, MID; Long: -177.40181, Lat: 28.19361 (WGS84); Sensor Depth: 1.00m; Data Range: 20030729-20041001.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  9. CRED Subsurface Temperature Recorder (STR); NWHI, PHR; Long: -175.81595, Lat: 27.85396 (WGS84); Sensor Depth: 7.62m; Data Range: 20060914-20080922.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  10. CRED Subsurface Temperature Recorder (STR); MHI, MAI; Long: -156.42031, Lat: 20.59198 (WGS84); Sensor Depth: 14.90m; Data Range: 20060805-20071009.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  11. CRED Subsurface Temperature Recorder (STR); NWHI, NEC; Long: -164.69775, Lat: 23.57152 (WGS84); Sensor Depth: 17.07m; Data Range: 20050414-20060904.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  12. CRED Subsurface Temperature Recorder (STR); MHI, LAN; Long: -156.83705, Lat: 20.87186 (WGS84); Sensor Depth: 13.11m; Data Range: 20081019-20101021.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  13. CRED Subsurface Temperature Recorder (STR); PRIA, JAR; Long: -159.99113, Lat: -00.36327 (WGS84); Sensor Depth: 9.75m; Data Range: 20060321-20080327.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  14. CRED Subsurface Temperature Recorder (STR); CNMI, SAI; Long: 145.78947, Lat: 15.17485 (WGS84); Sensor Depth: 19.20m; Data Range: 20080815-20090419.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  15. CRED Subsurface Temperature Recorder (STR); AMSM, TUT; Long: -170.72247, Lat: -14.28437 (WGS84); Sensor Depth: 8.23m; Data Range: 20060220-20080219.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  16. CRED Subsurface Temperature Recorder (STR); AMSM, TUT; Long: -170.72348, Lat: -14.27155 (WGS84); Sensor Depth: 17.68m; Data Range: 20080219-20100223.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  17. CRED Subsurface Temperature Recorder (STR); CNMI, FDP; Long: 144.89860, Lat: 20.53790 (WGS84); Sensor Depth: 11.28m; Data Range: 20070603-20090427.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  18. CRED Subsurface Temperature Recorder (STR); AMSM, OFU; Long: -169.62662, Lat: -14.18168 (WGS84); Sensor Depth: 10.67m; Data Range: 20060226-20071216.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  19. CRED Subsurface Temperature Recorder (STR); AMSM, TUT; Long: -170.76360, Lat: -14.36325 (WGS84); Sensor Depth: 16.70m; Data Range: 20070406-20080206.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  20. CRED Subsurface Temperature Recorder (STR); AMSM, ROS; Long: -168.15342, Lat: -14.53775 (WGS84); Sensor Depth: 2.40m; Data Range: 20080311-20100303.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  1. CRED Subsurface Temperature Recorder (STR); NWHI, PHR; Long: -175.81593, Lat: 27.85397 (WGS84); Sensor Depth: 7.90m; Data Range: 20040928-20060912.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  2. CRED Subsurface Temperature Recorder (STR); AMSM, ROS; Long: -168.16016, Lat: -14.55127 (WGS84); Sensor Depth: 3.40m; Data Range: 20080312-20090714.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  3. CRED Subsurface Temperature Recorder (STR); AMSM, ROS; Long: -168.16871, Lat: -14.54870 (WGS84); Sensor Depth: 16.50m; Data Range: 20080313-20091225.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  4. CRED Subsurface Temperature Recorder (STR); AMSM, SWA; Long: -171.09121, Lat: -11.05861 (WGS84); Sensor Depth: 28.96m; Data Range: 20080316-20090702.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  5. CRED Subsurface Temperature Recorder (STR); AMSM, TUT; Long: -170.66011, Lat: -14.24481 (WGS84); Sensor Depth: 13.41m; Data Range: 20070410-20080219.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  6. CRED Subsurface Temperature Recorder (STR); CNMI, FDP; Long: 144.88558, Lat: 20.54516 (WGS84); Sensor Depth: 18.59m; Data Range: 20070603-20070611.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  7. CRED Subsurface Temperature Recorder (STR); CNMI, PAG; Long: 145.76486, Lat: 18.09636 (WGS84); Sensor Depth: 14.63m; Data Range: 20070606-20081006.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  8. CRED Subsurface Temperature Recorder (STR); PRIA, HOW; Long: -176.62150, Lat: 00.80653 (WGS84); Sensor Depth: 17.98m; Data Range: 20080207-20100203.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  9. CRED Subsurface Temperature Recorder (STR); AMSM, TUT; Long: -170.83352, Lat: -14.32833 (WGS84); Sensor Depth: 27.74m; Data Range: 20080224-20100227.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  10. CRED Subsurface Temperature Recorder (STR); PRIA, PAL; Long: -162.00206, Lat: 05.87637 (WGS84); Sensor Depth: 32.61m; Data Range: 20080402-20100412.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  11. CRED Subsurface Temperature Recorder (STR); AMSM, OFU; Long: -169.62484, Lat: -14.16394 (WGS84); Sensor Depth: 6.40m; Data Range: 20060227-20070530.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  12. CRED Subsurface Temperature Recorder (STR); AMSM, TUT; Long: -170.76310, Lat: -14.36348 (WGS84); Sensor Depth: 13.41m; Data Range: 20080225-20100220.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  13. CRED Subsurface Temperature Recorder (STR); AMSM, TUT; Long: -170.75803, Lat: -14.37495 (WGS84); Sensor Depth: 30.78m; Data Range: 20080224-20100228.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  14. CRED Subsurface Temperature Recorder (STR); NWHI, FFS; Long: -166.27187, Lat: 23.85676 (WGS84); Sensor Depth: 7.92m; Data Range: 20070925-20091009.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  15. CRED Subsurface Temperature Recorder (STR); PRIA, KIN; Long: -162.38180, Lat: 06.42888 (WGS84); Sensor Depth: 5.18m; Data Range: 20080407-20100415.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  16. CRED Subsurface Temperature Recorder (STR); AMSM, OFU; Long: -169.65265, Lat: -14.17770 (WGS84); Sensor Depth: 1.22m; Data Range: 20080228-20100311.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  17. CRED Subsurface Temperature Recorder (STR); AMSM, TUT; Long: -170.56222, Lat: -14.28368 (WGS84); Sensor Depth: 8.23m; Data Range: 20050804-20060218.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  18. CRED Subsurface Temperature Recorder (STR); NWHI, MAR; Long: -170.51372, Lat: 25.36697 (WGS84); Sensor Depth: 4.27m; Data Range: 20040921-20060909.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  19. CRED Subsurface Temperature Recorder (STR); NWHI, MAR; Long: -170.64291, Lat: 25.47130 (WGS84); Sensor Depth: 14.33m; Data Range: 20060908-20080905.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  20. CRED Subsurface Temperature Recorder (STR); NWHI, MAR; Long: -170.63382, Lat: 25.44643 (WGS84); Sensor Depth: 8.53m; Data Range: 20040924-20060907.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  1. CRED Subsurface Temperature Recorder (STR); NWHI, MAR; Long: -170.53972, Lat: 25.38417 (WGS84); Sensor Depth: 1.50m; Data Range: 20030720-20040920.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  2. CRED Subsurface Temperature Recorder (STR); NWHI, MAR; Long: -170.51376, Lat: 25.36694 (WGS84); Sensor Depth: 4.27m; Data Range: 20060909-20080919.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  3. CRED Subsurface Temperature Recorder (STR); PRIA, JAR; Long: -160.00832, Lat: -00.36893 (WGS84); Sensor Depth: 32.30m; Data Range: 20060321-20080328.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  4. CRED Subsurface Temperature Recorder (STR); PRIA, PAL; Long: -162.11364, Lat: 05.86635 (WGS84); Sensor Depth: 19.20m; Data Range: 20090918-20100408.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  5. CRED Subsurface Temperature Recorder (STR); PRIA, HOW; Long: -176.62152, Lat: 00.80650 (WGS84); Sensor Depth: 18.60m; Data Range: 20040121-20060125.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  6. CRED Subsurface Temperature Recorder (STR); PRIA, WAK; Long: 166.59808, Lat: 19.31609 (WGS84); Sensor Depth: 10.97m; Data Range: 20051022-20070430.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  7. CRED Subsurface Temperature Recorder (STR); PRIA, WAK; Long: 166.60453, Lat: 19.30868 (WGS84); Sensor Depth: 1.52m; Data Range: 20051021-20070430.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  8. CRED Subsurface Temperature Recorder (STR); PRIA, JOH; Long: -169.48513, Lat: 16.74071 (WGS84); Sensor Depth: 2.13m; Data Range: 20080201-20100125.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  9. CRED Subsurface Temperature Recorder (STR); PRIA, PAL; Long: -162.08592, Lat: 05.88624 (WGS84); Sensor Depth: 3.70m; Data Range: 20040402-20060325.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  10. CRED Subsurface Temperature Recorder (STR); PRIA, PAL; Long: -162.06183, Lat: 05.88278 (WGS84); Sensor Depth: 4.26m; Data Range: 20060324-20080330.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  11. CRED Subsurface Temperature Recorder (STR); CNMI, TIN; Long: 145.65074, Lat: 15.03548 (WGS84); Sensor Depth: 7.32m; Data Range: 20050926-20070519.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  12. CRED Subsurface Temperature Recorder (STR); MHI, KAU; Long: -159.29895, Lat: 22.16533 (WGS84); Sensor Depth: 14.94m; Data Range: 20050715-20060808.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  13. CRED Subsurface Temperature Recorder (STR); CNMI, PAG; Long: 145.75748, Lat: 18.12728 (WGS84); Sensor Depth: 5.79m; Data Range: 20070605-20080513.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  14. CRED Subsurface Temperature Recorder (STR); NWHI, FFS; Long: -166.26140, Lat: 23.76891 (WGS84); Sensor Depth: 4.00m; Data Range: 20021005-20030715.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  15. CRED Subsurface Temperature Recorder (STR); NWHI, LIS; Long: -173.96097, Lat: 26.06337 (WGS84); Sensor Depth: 0.61m; Data Range: 20060925-20081005.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  16. CRED Subsurface Temperature Recorder (STR); PRIA, HOW; Long: -176.62216, Lat: 00.82351 (WGS84); Sensor Depth: 18.90m; Data Range: 20040122-20060226.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  17. CRED Subsurface Temperature Recorder (STR); AMSM, TUT; Long: -170.83339, Lat: -14.32838 (WGS84); Sensor Depth: 27.13m; Data Range: 20050805-20060221.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  18. CRED Subsurface Temperature Recorder (STR); NWHI, FFS; Long: -166.21967, Lat: 23.86611 (WGS84); Sensor Depth: 2.00m; Data Range: 20020912-20030714.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  19. CRED Subsurface Temperature Recorder (STR); PRIA, BAK; Long: -176.47574, Lat: 00.20538 (WGS84); Sensor Depth: 18.90m; Data Range: 20040124-20050605.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  20. CRED Subsurface Temperature Recorder (STR); NWHI, PHR; Long: -175.86298, Lat: 27.79096 (WGS84); Sensor Depth: 11.58m; Data Range: 20090920-20100518.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  1. CRED Subsurface Temperature Recorder (STR); MHI, FFP; Long: -160.60318, Lat: 21.68678 (WGS84); Sensor Depth: 18.90m; Data Range: 20081111-20100928.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  2. CRED Subsurface Temperature Recorder (STR); NWHI, PHR; Long: -175.86492, Lat: 27.94435 (WGS84); Sensor Depth: 35.05m; Data Range: 20060923-20070726.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  3. CRED Subsurface Temperature Recorder (STR); PRIA, JAR; Long: -159.97228, Lat: -00.37500 (WGS84); Sensor Depth: 30.70m; Data Range: 20060320-20080328.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  4. CRED Subsurface Temperature Recorder (STR); NWHI, MID; Long: -177.34437, Lat: 28.21823 (WGS84); Sensor Depth: 9.14m; Data Range: 20050701-20060915.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  5. CRED Subsurface Temperature Recorder (STR); PRIA, KIN; Long: -162.38440, Lat: 06.38252 (WGS84); Sensor Depth: 6.40m; Data Range: 20060330-20080404.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  6. CRED Subsurface Temperature Recorder (STR); NWHI, PHR; Long: -175.86165, Lat: 27.94069 (WGS84); Sensor Depth: 13.11m; Data Range: 20070806-20080923.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  7. CRED Subsurface Temperature Recorder (STR); NWHI, MID; Long: -177.34429, Lat: 28.21795 (WGS84); Sensor Depth: 9.45m; Data Range: 20060915-20080925.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  8. CRED Subsurface Temperature Recorder (STR); PRIA, JOH; Long: -169.48513, Lat: 16.74080 (WGS84); Sensor Depth: 2.10m; Data Range: 20040116-20060120.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  9. CRED Subsurface Temperature Recorder (STR); CNMI, MAU; Long: 145.20772, Lat: 20.01772 (WGS84); Sensor Depth: 2.13m; Data Range: 20070530-20090430.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  10. CRED Subsurface Temperature Recorder (STR); NWHI, PHR; Long: -175.73123, Lat: 27.86606 (WGS84); Sensor Depth: 22.25m; Data Range: 20080924-20100914.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  11. CRED Subsurface Temperature Recorder (STR); AMSM, TAU; Long: -169.44661, Lat: -14.25073 (WGS84); Sensor Depth: 6.10m; Data Range: 20060303-20080302.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  12. CRED Subsurface Temperature Recorder (STR); NWHI, FFS; Long: -166.26134, Lat: 23.76895 (WGS84); Sensor Depth: 4.57m; Data Range: 20080915-20100908.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  13. CRED Subsurface Temperature Recorder (STR); NWHI, PHR; Long: -175.88108, Lat: 27.78202 (WGS84); Sensor Depth: 22.86m; Data Range: 20080923-20081110.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  14. CRED Subsurface Temperature Recorder (STR); PRIA, JAR; Long: -159.99670, Lat: -00.38208 (WGS84); Sensor Depth: 32.30m; Data Range: 20060321-20080327.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  15. CRED Subsurface Temperature Recorder (STR); NWHI, FFS; Long: -166.16685, Lat: 23.73815 (WGS84); Sensor Depth: 2.13m; Data Range: 20060906-20081008.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  16. CRED Subsurface Temperature Recorder (STR); NWHI, FFS; Long: -166.17350, Lat: 23.64478 (WGS84); Sensor Depth: 2.00m; Data Range: 20030717-20040919.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  17. CRED Subsurface Temperature Recorder (STR); NWHI, KUR; Long: -178.35620, Lat: 28.45155 (WGS84); Sensor Depth: 20.12m; Data Range: 20081001-20100918.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  18. CRED Subsurface Temperature Recorder (STR); NWHI, LIS; Long: -173.99797, Lat: 26.10004 (WGS84); Sensor Depth: 22.56m; Data Range: 20090929-20100517.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  19. CRED Subsurface Temperature Recorder (STR); AMSM, OFU; Long: -169.65220, Lat: -14.18020 (WGS84); Sensor Depth: 6.10m; Data Range: 20060228-20080228.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  20. CRED Subsurface Temperature Recorder (STR); CNMI, TIN; Long: 145.65072, Lat: 15.03548 (WGS84); Sensor Depth: 6.71m; Data Range: 20070519-20070905.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  1. CRED Subsurface Temperature Recorder (STR); PRIA, HOW; Long: -176.62401, Lat: 00.81480 (WGS84); Sensor Depth: 14.63m; Data Range: 20080207-20100203.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  2. CRED Subsurface Temperature Recorder (STR); CNMI, AGR; Long: 145.63819, Lat: 18.76656 (WGS84); Sensor Depth: 1.52m; Data Range: 20070528-20090502.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  3. CRED Subsurface Temperature Recorder (STR); NWHI, GAR; Long: -167.99958, Lat: 24.99883 (WGS84); Sensor Depth: 10.36m; Data Range: 20040920-20060705.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  4. CRED Subsurface Temperature Recorder (STR); NWHI, PHR; Long: -175.78082, Lat: 27.95763 (WGS84); Sensor Depth: 1.22m; Data Range: 20080923-20100916.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  5. CRED Subsurface Temperature Recorder (STR); AMSM, OFU; Long: -169.62661, Lat: -14.18177 (WGS84); Sensor Depth: 11.28m; Data Range: 20080229-20100311.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  6. CRED Subsurface Temperature Recorder (STR); MHI, MAI; Long: -156.42033, Lat: 20.59195 (WGS84); Sensor Depth: 14.63m; Data Range: 20081018-20101020.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  7. CRED Subsurface Temperature Recorder (STR); MHI, MAI; Long: -156.15120, Lat: 20.86456 (WGS84); Sensor Depth: 14.63m; Data Range: 20081018-20101016.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  8. CRED Subsurface Temperature Recorder (STR); MHI, MAI; Long: -156.42031, Lat: 20.59198 (WGS84); Sensor Depth: 14.90m; Data Range: 20071009-20081018.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  9. CRED Subsurface Temperature Recorder (STR); MHI, MAI; Long: -156.58458, Lat: 20.79070 (WGS84); Sensor Depth: 14.60m; Data Range: 20050806-20070402.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  10. CRED Subsurface Temperature Recorder (STR); MHI, MAI; Long: -156.49718, Lat: 20.63030 (WGS84); Sensor Depth: 11.58m; Data Range: 20050807-20101017.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  11. CRED Subsurface Temperature Recorder (STR); MHI, MAI; Long: -156.58448, Lat: 20.79079 (WGS84); Sensor Depth: 11.89m; Data Range: 20081024-20100326.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  12. CRED Subsurface Temperature Recorder (STR); NWHI, LAY; Long: -171.72929, Lat: 25.75915 (WGS84); Sensor Depth: 0.91m; Data Range: 20060910-20080920.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  13. CRED Subsurface Temperature Recorder (STR); CNMI, MAU; Long: 145.20730, Lat: 20.01768 (WGS84); Sensor Depth: 10.67m; Data Range: 20050911-20070530.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  14. CRED Subsurface Temperature Recorder (STR); MHI, MOL; Long: -157.25236, Lat: 21.20307 (WGS84); Sensor Depth: 10.36m; Data Range: 20081024-20101023.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  15. CRED Subsurface Temperature Recorder (STR); CNMI, ZEA; Long: 145.85335, Lat: 16.89749 (WGS84); Sensor Depth: 24.68m; Data Range: 20070526-20090505.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  16. CRED Subsurface Temperature Recorder (STR); CNMI, ROT; Long: 145.20680, Lat: 14.18284 (WGS84); Sensor Depth: 10.36m; Data Range: 20070516-20090409.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Coral Reef Ecosystem Division (CRED), NOAA Pacific Islands Fisheries Science Center (PIFSC) Subsurface Temperature Recorders (STR) provide a time series of...

  17. Quasiclassical Trajectory Calculations of the Rate Constant of the OH + HBr → Br + H2O Reaction Using a Full-Dimensional Ab Initio Potential Energy Surface Over the Temperature Range 5 to 500 K.

    Science.gov (United States)

    de Oliveira-Filho, Antonio G S; Ornellas, Fernando R; Bowman, Joel M

    2014-02-20

    We report a permutationally invariant, ab initio potential energy surface (PES) for the OH + HBr → Br + H2O reaction. The PES is a fit to roughly 26 000 spin-free UCCSD(T)/cc-pVDZ-F12a energies and has no classical barrier to reaction. It is used in quasiclassical trajectory calculations with a focus on the thermal rate constant, k(T), over the temperature range 5 to 500 K. Comparisons with available experimental data over the temperature range 23 to 416 K are made using three approaches to treat the OH rotational and associated electronic partition function. All display an inverse temperature dependence of k(T) below roughly 160 K and a nearly constant temperature dependence above 160 K, in agreement with experiment. The calculated rate constant with no treatment of spin-orbit coupling is overall in the best agreement with experiment, being (probably fortuitously) within 20% of it.

  18. Temperature evolution of the dielectric response function of Pb(Fe0.95Sc0.05)2/3W1/3O3 relaxor ceramics in a wide frequency range

    Science.gov (United States)

    Komandin, G. A.; Porodinkov, O. E.; Bush, A. A.; Koroleva, A. F.; Spektor, I. E.; Chuchupal, S. V.; Seregin, D. S.; Iskhakova, L. D.

    2017-12-01

    Electrodynamic properties of Pb(Fe0.95Sc0.05)2/3W1/3O3 solid solution belonging to A(B'B'')O3 perovskite structural family have been investigated by broadband dielectric spectroscopy in a wave-number range of (4 × 10-9-4 × 103) cm-1 and a temperature range of 100-600 K. The influence of low-frequency relaxations on the vibrational spectrum is determined within the four-parameter factorized dispersion model. Anomalies in the behavior of the dielectric response function are found near the temperature-diffuse maximum of permittivity.

  19. Evolution of structure and magnetic properties for BaFe{sub 11.9}Al{sub 0.1}O{sub 19} hexaferrite in a wide temperature range

    Energy Technology Data Exchange (ETDEWEB)

    Trukhanov, A.V., E-mail: truhanov86@mail.ru [National University of Science and Technology MISiS, Leninsky Prospekt, 4, 119049 Moscow (Russian Federation); SSPA “Scientific and Practical Materials Research Centre of NAS of Belarus”, P. Brovki str., 19, 220072 Minsk, Belorussia (Belarus); Trukhanov, S.V. [National University of Science and Technology MISiS, Leninsky Prospekt, 4, 119049 Moscow (Russian Federation); SSPA “Scientific and Practical Materials Research Centre of NAS of Belarus”, P. Brovki str., 19, 220072 Minsk, Belorussia (Belarus); Panina, L.V.; Kostishyn, V.G. [National University of Science and Technology MISiS, Leninsky Prospekt, 4, 119049 Moscow (Russian Federation); Kazakevich, I.S. [SSPA “Scientific and Practical Materials Research Centre of NAS of Belarus”, P. Brovki str., 19, 220072 Minsk, Belorussia (Belarus); Trukhanov, An.V. [National University of Science and Technology MISiS, Leninsky Prospekt, 4, 119049 Moscow (Russian Federation); SSPA “Scientific and Practical Materials Research Centre of NAS of Belarus”, P. Brovki str., 19, 220072 Minsk, Belorussia (Belarus); Trukhanova, E.L.; Natarov, V.O. [SSPA “Scientific and Practical Materials Research Centre of NAS of Belarus”, P. Brovki str., 19, 220072 Minsk, Belorussia (Belarus); Turchenko, V.A. [Joint Institute for Nuclear Research, Joliot-Curie Str., 6, 141980 Dubna (Russian Federation); Donetsk Institute of Physics and Technology named after A.A. Galkin of the NAS of Ukraine, 72 R.Luxemburg Str., 83114 Donetsk (Ukraine); Salem, M.M. [National University of Science and Technology MISiS, Leninsky Prospekt, 4, 119049 Moscow (Russian Federation); and others

    2017-03-15

    M-type BaFe{sub 11.9}Al{sub 0.1}O{sub 19} hexaferrite was successfully synthesized by solid state reactions. Precision investigations of crystal and magnetic structures of BaFe{sub 11.9}Al{sub 0.1}O{sub 19} powder by neutron diffraction in the temperature range 4.2–730 K have been performed. Magnetic and electrical properties investigations were carried out in the wide temperature range. Neutron powder diffraction data were successfully refined in approximation for both space groups (SG): centrosymmetric #194 (standard non-polar phase) and non-centrosymmetric #186 (polar phase). It has been shown that at low temperatures (below room temperature) better fitting results (value χ{sup 2}) were for the polar phase (SG: #186) or for the two phases coexistence (SG: #186 and SG: #194). At high temperatures (400–730 K) better fitting results were for SG: #194. It was established coexistence of the dual ferroic properties (specific magnetization and spontaneous polarization) at room temperature. Strong correlation between magnetic and electrical subsystems was demonstrated (magnetoelectrical effect). Temperature dependences of the spontaneous polarization, specific magnetization and magnetoelectrical effect were investigated.

  20. Performance Evaluation of an Automotive-Grade, High Speed Gate Driver for SiC FETs, Type UCC27531, Over a Wide Temperature Range

    Science.gov (United States)

    Boomer, Kristen; Hammoud, Ahmad

    2015-01-01

    Silicon carbide (SiC) devices are becoming widely used in electronic power circuits as replacement for conventional silicon parts due to their attractive properties that include low on-state resistance, high temperature tolerance, and high frequency operation. These attributes have a significant impact by reducing system weight, saving board space, and conserving power. In this work, the performance of an automotive-grade high speed gate driver with potential use in controlling SiC FETs (field-Effect Transistors) in converters or motor control applications was evaluated under extreme temperatures and thermal cycling. The investigations were carried out to assess performance and to determine suitability of this device for use in space exploration missions under extreme temperature conditions.

  1. Changes in mechanical properties of the OKh16N15M3B steel in the temperature range of radiation-induced swelling

    International Nuclear Information System (INIS)

    Neustroev, V.S.; Golovanov, V.N.; Povstyanko, A.V.; Shamardin, V.K.

    1986-01-01

    Presented are the results of investigations of both swelling and mechanical properties of the fuel element cans of BOR-60 reactor of the 0Kh16N15M3B steel after austenitization. The dose-temperature dependences have been plotted swelling and radiation-induced porosity parameters as well as for mechanical properties of the above steel. Interpretation of changes in some 0Kh16N15M3B steel mechanical properties with dose and temperature has been proposed based on Orovan's mechanism and on that for crack nucleation with voids present

  2. Influence of temperature on Pr:YAlO.sub.3./sub. laser operation in the orange and near-infrared spectral range

    Czech Academy of Sciences Publication Activity Database

    Fibrich, Martin; Šulc, J.; Jelínková, H.

    2014-01-01

    Roč. 11, č. 10 (2014), s. 105801 ISSN 1612-2011 Institutional support: RVO:68378271 Keywords : Pr:YAlO 3 * diode pumping * InGaN laser diode * cryogenic temperature Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.458, year: 2014

  3. Validation of HITEMP-2010 for carbon dioxide and water vapour at high temperatures and atmospheric pressures in 450-7600cm-1 spectral range

    DEFF Research Database (Denmark)

    Alberti, Michael; Weber, Roman; Mancini, Marco

    2015-01-01

    The objective of the work is validation of HITEMP-2010 at atmospheric pressures and temperatures reaching 1770K. To this end, spectral transmissivities at 1cm-1 resolution and excellent signal-to-noise-ratio have been measured for 22 CO2/H2O/N2 mixtures. In this paper we consider the 450cm-1-7600cm...

  4. A new method suitable for calculating accurately wetting temperature over a wide range of conditions: Based on the adaptation of continuation algorithm to classical DFT

    Science.gov (United States)

    Zhou, Shiqi

    2017-11-01

    A new scheme is put forward to determine the wetting temperature (Tw) by utilizing the adaptation of arc-length continuation algorithm to classical density functional theory (DFT) used originally by Frink and Salinger, and its advantages are summarized into four points: (i) the new scheme is applicable whether the wetting occurs near a planar or a non-planar surface, whereas a zero contact angle method is considered only applicable to a perfectly flat solid surface, as demonstrated previously and in this work, and essentially not fit for non-planar surface. (ii) The new scheme is devoid of an uncertainty, which plagues a pre-wetting extrapolation method and originates from an unattainability of the infinitely thick film in the theoretical calculation. (iii) The new scheme can be similarly and easily applied to extreme instances characterized by lower temperatures and/or higher surface attraction force field, which, however, can not be dealt with by the pre-wetting extrapolation method because of the pre-wetting transition being mixed with many layering transitions and the difficulty in differentiating varieties of the surface phase transitions. (iv) The new scheme still works in instance wherein the wetting transition occurs close to the bulk critical temperature; however, this case completely can not be managed by the pre-wetting extrapolation method because near the bulk critical temperature the pre-wetting region is extremely narrow, and no enough pre-wetting data are available for use of the extrapolation procedure.

  5. Influence of deuterium content on tensile behavior of Zr-2.5Nb pressure tube material in the temperature range of ambient to 300 degC

    International Nuclear Information System (INIS)

    Bind, A.K.; Singh, R.N.; Chakravartty, J.K.; Dhandharia, Priyesh; Ghosh, Agnish; More, Nitin S.; Chhatre, A.G.; Vijayakumar, S.

    2011-08-01

    Tensile properties of autoclaved zirconium-2.5 wt. % niobium pressure tube material were evaluated by uniaxial tension tests at temperatures between 25 and 300 degC and under strain-rates of 1.075 x 10 -4 /s. Six number of Zr-2.5Nb alloy pressure tube spools of length 130 mm were obtained from pressure tube number 19-2557-2. Five spools were polished with abrasive paper to remove the oxide layer. These spools were gaseously charged with controlled amount of deuterium. The target deuterium concentrations were 25, 50, 75, 100 and 200 wppm of hydrogen equivalent. Ten samples were machined by EDM wire cutting from every spool. The tensile specimen axis was oriented along longitudinal direction of the tube. Metallographic examination of the deuterium charged samples suggested that the deuterides were predominantly circumferential deuterides. Analysis of tensile results showed that both yield and ultimate tensile strengths of this alloy decreased monotonically with increasing test temperatures. The tensile ductility decreased marginally with increase in test temperature from ambient to 300 degC. It was also observed that both strength and ductility appear to be unaffected by deuterium content at all temperatures, thereby suggesting that at least up to 200 wppm (Heq.) of deuterium tensile properties are not influenced by deuterium. (author)

  6. Thermal stability of a highly-deformed warm-rolled tungsten plate in the temperature range 1100 °C to 1250 °C

    DEFF Research Database (Denmark)

    Alfonso Lopez, Angel; Juul Jensen, Dorte; Luo, G.-N.

    2015-01-01

    Pure tungsten is considered as armor material for the most critical parts of fusion reactors (i.e. the divertor and the first wall), among other reasons due to its high melting point (3422 °C) and recrystallization temperature. The thermal stability of a pure tungsten plate warm-rolled to a high...

  7. Experimental formation of cronstedtite from Cox argillite-iron interaction at decreasing temperature in the 90 deg. C-40 deg. C range

    International Nuclear Information System (INIS)

    Pignatelli, Isabella; Mosser-Ruck, Regine; Rozsypal, Christophe; Truche, Laurent; Randi, Aurelien; Bartier, Daniele; Cathelineau, Michel; Ghanbaja, Jaafar; Mouton, Ludovic; Michau, Nicolas

    2012-01-01

    Document available in extended abstract form only. Cronstedtite crystals experimentally formed during a cooling experiment (90 deg.C-40 deg. C) simulating the time-temperature evolution of the iron-clay system around the steel overpacks in nuclear waste disposal, were characterized by XRD, SEM and TEM study. Cronstedtite is a T-O phyllosilicate with general formula (Fe 2+ 3-x Fe 3+ x )(Si 2-x Fe 3+ x )O 5 (OH) 4 , with 0 2 ), Callovo-Oxfordian argillite (COx) of the Paris Basin (with a solution/COx mass ratio of 10) and metal iron (powder and plates, with an iron powder/COx mass ratio of 0.5). This system was put in Teflon-line autoclaves heated at (90±2) deg. C for 6 months; then the temperature was decreased every month by step of 10 deg. C until 40 deg. C. The XRD results on run products clearly show that the T-O phyllosilicates crystallize and replace the predominant clay in the starting argillite, e.g. illite-smectite mixed-layer clays when the experimental temperature decreases. The reflections at 7.1 Angstrom, 4.76 Angstrom, 3.55 Angstrom and 2.73 Angstrom indicate that the T-O phyllosilicate formed is cronstedtite, but this technique is not efficient to determine its polytype. The SEM analyses confirm the presence of cronstedtite and show the morphological evolution of crystals with the temperature. At 90 deg. C three morphologies are recognized: trigonal pyramids and cones with hexagonal or rounded cross-section (Fig. 1), these crystals coexist with hairy berthierine-like minerals, as described by [10] and [12] The three cronstedtite shapes are observed until 70 deg. C and at lower temperatures the pyramidal morphology is dominant. From the energy dispersive X-ray analyses, structural formula of cronstedtite were calculated. The Fe II / Fe III ratio was adjusted to fix the octahedron to 3 in the calculation of the structural formula. Slight differences in the chemical compositions of cronstedtites are noticed: the pyramidal crystals have more Fe 2+ in the

  8. An Optically Isotropic Antiferroelectric Liquid Crystal (OI-AFLC) Display Mode Operating over a Wide Temperature Range using Ternary Bent-Core Liquid Crystal Mixtures.

    Science.gov (United States)

    Bergquist, Leah; Zhang, Cuiyu; Ribeiro de Almeida, Roberta R; Pellegrene, Brittany; Salamonczyk, Miroslaw; Kim, Matthew; Hwang, Jung-Im; Kim, Kyeong-Jin; Lee, Joun-Ho; Jákli, Antal; Hegmann, Torsten

    2017-04-01

    We report on the synthesis and characterization of bent-core liquid crystal (LC) compounds and the preparation of mixtures that provide an optically isotropic antiferroelectric (OI-AFLC) liquid crystal display mode over a very wide temperature interval and well below room temperature. From the collection of compounds synthesized during this study, we recognized that several ternary mixtures displayed a modulated SmC a P A phase down to below -40 °C and up to about 100 °C on both heating and cooling, as well as optical tilt angles in the transformed state of approximately 45° (optically isotropic state). The materials were fully characterized and their liquid crystal as well as electro-optical properties analyzed by polarized optical microscopy, differential scanning calorimetry, synchrotron X-ray diffraction, dielectric spectroscopy, and electro-optical tests.

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

    Directory of Open Access Journals (Sweden)

    Seung-Mi Moon

    2014-01-01

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

  10. Effects of predicted future and current atmospheric temperature and [CO2] and high and low soil moisture on gas exchange and growth of Pinus taeda seedlings at cool and warm sites in the species range.

    Science.gov (United States)

    Wertin, Timothy M; McGuire, Mary Anne; Teskey, Robert O

    2012-07-01

    Predicted future changes in air temperature and atmospheric CO(2) concentration ([CO(2)]), coupled with altered precipitation, are expected to substantially affect tree growth. Effects on growth may vary considerably across a species range, as temperatures vary from sub-optimal to supra-optimal for growth. We performed an experiment simultaneously at two locations in the current range of loblolly pine, a cool site and a warm site, to examine the effect of future climate conditions on growth of loblolly pine seedlings in contrasting regions of the species range. At both sites 1-year-old loblolly pine seedlings were grown in current (local ambient temperature and [CO(2)]) and predicted future atmospheric conditions (ambient +2 °C temperature and 700 μmol mol(-1) [CO(2)]). Additionally, high and low soil moisture treatments were applied within each atmospheric treatment at each site by altering the amount of water provided to the seedlings. Averaged across water treatments, photosynthesis (A(net)) was 31% greater at the cool site and 34% greater at the warm site in elevated temperature and [CO(2)] compared with ambient temperature. Biomass accumulation was also stimulated by 38% at the cool site and by 24% at the warm site in that treatment. These results suggest that a temperature increase of 2 °C coupled with an increase in [CO(2)] (predicted future climate) will create conditions favorable for growth of this species. Reduced soil moisture decreased growth in both current and predicted atmospheric conditions. Biomass accumulation and A(net) were reduced by ∼39 and 17%, respectively, in the low water treatment. These results suggest that any benefit of future atmospheric conditions may be negated if soil moisture is reduced by altered precipitation patterns.

  11. Soil temperature and moisture dynamics after experimental irrigation on two contrasting soils on the Santa Rita Experimental Range: Implications for mesquite establishment

    Science.gov (United States)

    Nathan B. English; David G. Williams; Jake F. Weltzin

    2003-01-01

    We established a large-scale manipulative experiment in a semidesert grassland on the Santa Rita Experimental Range to determine how the recruitment and physiology of woody plants (Prosopis velutina Woot.) are affected by invasive grasses, seasonal precipitation regimes, and underlying soil characteristics. We established 72 2.8-m2 plots beneath six large rainout...

  12. Influences of temperature and environmental variables on the distribution of bull trout within streams at the southern margin of its range

    Science.gov (United States)

    J. Dunham; B. Rieman; G. Chandler

    2003-01-01

    The bull trout Salvelinus confluentus is believed to be among the most thermally sensitive species in coldwater habitats in western North America. We conducted a comprehensive field assessment of thermal habitat associations throughout the southern margin of the species' range. We developed models of thermal habitat associations using two data sets representing a...

  13. Physical and Magnetic Properties of La0.5Ca0.5Mn0.9Cu0.1O3 at Temperature in the Range of 10-100 K

    Science.gov (United States)

    Gunanto, Y. E.; Adi, W. A.; Steven, E.; Kurniawan, B.; Ono, T.; Tanaka, H.

    2017-05-01

    We have successfully measured physical and magnetic properties of the La0.5Ca0.5Mn0.9Cu0.1O3 at temperature in the range of 10-100 K. Physical properties have covered electrical resistivity and specific heat. The properties, which serve as a function of temperature, were investigated by using Physics Properties Measurement System (PPMS) with and without an external magnetic field up to 8.5 Tesla. The magnetic structure was characterized using High-Resolution Powder Diffraction (HRPD) at room and low temperatures. Furthermore, the magnetization was measured by using Magnetic Properties Measurement System (MPMS) with the external magnetic field of 0-7 Tesla. In the temperature interval of 10-53 K, the resistivity of the sample increased with the increasing of external magnetic field. At temperatures T 53 K, the sample was an insulator according to fittings Ln R as a function of 1/T 0.25. The result was also shown by the decreasing value of the resistivity of the sample. The transition temperature of the metal-insulator (TMI ) decreased with the increasing of external magnetic field, i.e. from 60 K without an external magnetic field to 53 K with external magnetic field 8.5 Tesla. A coefficient electron specific heat and specific heat of spin wave increased, and phonon specific heat was relatively unchanged in the presence of an external magnetic field. Results of HRPD experiment were analyzed by using Fullprof program. At room temperature, the sample had the paramagnetic phase, while at low temperatures of 20 K it had antiferromagnetic phase. Temperature phase transition from the paramagnetic to antiferromagnetic phase or Neel temperature was around 225 K. However, the saturation magnetization of the sample was not observed.

  14. Temperature-tuned Maxwell-Boltzmann neutron spectra for kT ranging from 30 up to 50 keV for nuclear astrophysics studies.

    Science.gov (United States)

    Martín-Hernández, G; Mastinu, P F; Praena, J; Dzysiuk, N; Capote Noy, R; Pignatari, M

    2012-08-01

    The need of neutron capture cross section measurements for astrophysics motivates present work, where calculations to generate stellar neutron spectra at different temperatures are performed. The accelerator-based (7)Li(p,n)(7)Be reaction is used. Shaping the proton beam energy and the sample covering a specific solid angle, neutron activation for measuring stellar-averaged capture cross section can be done. High-quality Maxwell-Boltzmann neutron spectra are predicted. Assuming a general behavior of the neutron capture cross section a weighted fit of the spectrum to Maxwell-Boltzmann distributions is successfully introduced. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Briquetting of Egyptian ilmenite ore with different organic binder and reduced its in hydrogen in temperature range 800-1200°C

    Directory of Open Access Journals (Sweden)

    Abd El-Gawad H.H.

    2014-01-01

    Full Text Available Ilmenite ore fine was briquetted with different amounts of molasses or pitch pressed under different pressure was studied in this investigation. The results show at optimum amount of molasses added was 1.5 % and pitch, the pressure was 294.3 M.Pa.. Also the characterizations of raw materials were studied by different methods of analyses such as Xray and screen analyses. The produced briquettes were reduced by different amounts of hydrogen at different temperatures, and the reduction kinetics was determined.

  16. Electrophysical properties of silicon layers implanted with erbium and oxygen ions over a wide dose range and heat treated with different temperature regimes

    CERN Document Server

    Aleksandrov, O V; Sobolev, N A; Nikolaev, Y A

    2002-01-01

    The electrophysical properties of silicon implanted with erbium and oxygen ions over a wide dose range have been studied. The electron mobility dependence on the electrically active center concentration has been obtained in erbium-doped silicon with a concentration varied over 9 x 10 sup 1 sup 5 - 8 x 10 sup 1 sup 6 cm sup - sup 3 range. In the concentration profiles of electrically active centers n(x) and erbium atoms C(x), irregularities related to some peculiarities of the Er segregation during solid phase epitaxial recrystallization were found. They are regarded as peculiar to erbium ion implantation doses higher than the amorphization thresholds. A linear increase of a maximum concentration of electrically active centers and practically constant effective coefficient k of their activation have been observed at the erbium ion implantation doses higher than the amorphization threshold. An increase in the electrically active center concentration gains saturation and k drops at the erbium concentration highe...

  17. Measurement of Thermal Conductivity of Porcine Liver in the Temperature Range of Cryotherapy and Hyperthermia (250~315k) by A Thermal Sensor Made of A Micron-Scale Enameled Copper Wire.

    Science.gov (United States)

    Jiang, Z D; Zhao, G; Lu, G R

      BACKGROUND: Cryotherapy and hyperthermia are effective treatments for several diseases, especially for liver cancers. Thermal conductivity is a significant thermal property for the prediction and guidance of surgical procedure. However, the thermal conductivities of organs and tissues, especially over the temperature range of both cryotherapy and hyperthermia are scarce. To provide comprehensive thermal conductivity of liver for both cryotherapy and hyperthermia. A hot probe made of stain steel needle and micron-sized copper wire is used for measurement. To verify data processing, both the least square method and the Monte Carlo inversion method are used to determine the hot probe constants, respectively, with reference materials of water and 29.9 % Ca 2 Cl aqueous solution. Then the thermal conductivities of Hanks solution and pork liver bathed in Hanks solution are measured. The effective length for two methods is nearly the same, but the heat capacity of probe calibrated by the Monte Carlo inversion is temperature dependent. Fairly comprehensive thermal conductivity of porcine liver measured with these two methods in the target temperature range is verified to be similar. We provide an integrated thermal conductivity of liver for cryotherapy and hyperthermia in two methods, and make more accurate predictions possible for surgery. The least square method and the Monte Carlo inversion method have their advantages and disadvantages. The least square method is available for measurement of liquids that not prone to convection or solids in a wide temperature range, while the Monte Carlo inversion method is available for accurate and rapid measurement.

  18. Sub-Zero Temperature Chromatography for Reduced Back-Exchange and Improved Dynamic Range in Amide Hydrogen Deuterium Exchange Mass Spectrometry

    OpenAIRE

    Venable, John D.; Okach, Linda; Agarwalla, Sanjay; Brock, Ansgar

    2012-01-01

    Amide hydrogen/deuterium exchange is a commonly used technique for studying the dynamics of proteins and their interactions with other proteins or ligands. When coupled with liquid chromatography and mass spectrometry, hydrogen/deuterium exchange provides several unique advantages over other structural characterization techniques including very high sensitivity, the ability to analyze proteins in complex environments, and a large mass range. A fundamental limitation of the technique arises fr...

  19. Model description of the equivalent electroconductivity of aqueous solutions of alkali metal hydroxides over a wide range of concentrations and temperatures

    Science.gov (United States)

    Kuznetsova, E. M.; Volkov, D. S.

    2011-09-01

    The possibility of a quantitative theoretical description of the λ( c) dependence for aqueous solutions of alkali metal hydroxides in a wide concentration (from 0.0001 to 12 M) and temperature (from 0 to 100°C) was considered on the basis of concept suggested earlier. Effectiveness of the description of characteristics analyzed was illustrated on the examples of the calculation of electroconductivity values for aqueous LiOH, NaOH, KOH, RbOH, and CsOH solutions and comparison of them with experimental values taken from published data. The suggestion on different H+ and OH- ion migration mechanism was made on the basis of the model used for description of λ( c).

  20. Investigation on cause of outage of Wide Range Monitor (WRM) in High Temperature engineering Test Reactor (HTTR). Transport operation toward investigation for cause of outage

    International Nuclear Information System (INIS)

    Shinohara, Masanori; Sawahata, Hiroaki; Kawamoto, Taiki; Saito, Kenji; Takada, Shoji; Yoshida, Naoaki; Isozaki, Ryosuke; Katsuyama, Kozo; Motegi, Toshihiro

    2012-08-01

    An event, in which one of WRMs were disabled to detect the neutron flux in the reactor core, occurred during the period of reactor shut down of HTTR in March, 2010. The actual life time of WRM was unexpectedly shorter than the past developed life time. Investigation of the cause of the outage of WRM toward the recovery of the life time up to the developed life is one of the issues to develop the technology basis of High Temperature Gas cooled Reactor (HTGR). Then, a post irradiation examination was planned to specify the damaged part causing the event in the WRM was also planned. For the investigation, the X-ray computed tomography scanner in Fuels Monitoring Facility (FMF). This report describes the preliminary investigation on the cause of outage of the WRM. The results of study for transportation method of the irradiated WRM from HTTR to FMF is also reported with the record to complete the transport operation. (author)