WorldWideScience

Sample records for included temperature dew

  1. Automatic dew-point temperature sensor.

    Science.gov (United States)

    Graichen, H; Rascati, R; Gonzalez, R R

    1982-06-01

    A device is described for measuring dew-point temperature and water vapor pressure in small confined areas. The method is based on the deposition of water on a cooled surface when at dew-point temperature. A small Peltier module lowers the temperature of two electrically conductive plates. At dew point the insulating gap separating the plates becomes conductive as water vapor condenses. Sensors based on this principle can be made small and rugged and can be used for measuring directly the local water vapor pressure. They may be installed within a conventional ventilated sweat capsule used for measuring water vapor loss from the skin surface. A novel application is the measurement of the water vapor pressure gradients across layers of clothing worn by an exercising subject.

  2. Comparison of dew point temperature estimation methods in Southwestern Georgia

    Science.gov (United States)

    Marcus D. Williams; Scott L. Goodrick; Andrew Grundstein; Marshall Shepherd

    2015-01-01

    Recent upward trends in acres irrigated have been linked to increasing near-surface moisture. Unfortunately, stations with dew point data for monitoring near-surface moisture are sparse. Thus, models that estimate dew points from more readily observed data sources are useful. Daily average dew temperatures were estimated and evaluated at 14 stations in...

  3. Temperature distribution model for the semiconductor dew point detector

    Science.gov (United States)

    Weremczuk, Jerzy; Gniazdowski, Z.; Jachowicz, Ryszard; Lysko, Jan M.

    2001-08-01

    The simulation results of temperature distribution in the new type silicon dew point detector are presented in this paper. Calculations were done with use of the SMACEF simulation program. Fabricated structures, apart from the impedance detector used to the dew point detection, contained the resistive four terminal thermometer and two heaters. Two detector structures, the first one located on the silicon membrane and the second one placed on the bulk materials were compared in this paper.

  4. Accurate dew-point measurement over a wide temperature range using a quartz crystal microbalance dew-point sensor

    Science.gov (United States)

    Kwon, Su-Yong; Kim, Jong-Chul; Choi, Buyng-Il

    2008-11-01

    Quartz crystal microbalance (QCM) dew-point sensors are based on frequency measurement, and so have fast response time, high sensitivity and high accuracy. Recently, we have reported that they have the very convenient attribute of being able to distinguish between supercooled dew and frost from a single scan through the resonant frequency of the quartz resonator as a function of the temperature. In addition to these advantages, by using three different types of heat sinks, we have developed a QCM dew/frost-point sensor with a very wide working temperature range (-90 °C to 15 °C). The temperature of the quartz surface can be obtained effectively by measuring the temperature of the quartz crystal holder and using temperature compensation curves (which showed a high level of repeatability and reproducibility). The measured dew/frost points showed very good agreement with reference values and were within ±0.1 °C over the whole temperature range.

  5. The Influence of Air Temperature on the Dew Point Temperature in ...

    African Journals Online (AJOL)

    ADOWIE PERE

    done to determine the influence and effect of temperature on other climatic environmental ... Key words: Air Temperature, Dew point temperature, Weather, Climate, Influence. Weather ... humidity, clouds and atmospheric pressure. Its.

  6. Estimation of precipitable water from surface dew point temperature

    International Nuclear Information System (INIS)

    Abdel Wahab, M.; Sharif, T.A.

    1991-09-01

    The Reitan (1963) regression equation which is of the form lnw=a+bT d has been examined and tested to estimate precipitable water content from surface dew point temperature at different locations. The study confirms that the slope of this equation (b) remains constant at the value of .0681 deg. C., while the intercept (a) changes rapidly with the latitude. The use of the variable intercept can improve the estimated result by 2%. (author). 6 refs, 4 figs, 3 tabs

  7. Investigation of potential factors affecting the measurement of dew point temperature in oil-soaked transformers

    Science.gov (United States)

    Kraus, Adam H.

    Moisture within a transformer's insulation system has been proven to degrade its dielectric strength. When installing a transformer in situ, one method used to calculate the moisture content of the transformer insulation is to measure the dew point temperature of the internal gas volume of the transformer tank. There are two instruments commercially available that are designed for dew point temperature measurement: the Alnor Model 7000 Dewpointer and the Vaisala DRYCAPRTM Hand-Held Dewpoint Meter DM70. Although these instruments perform an identical task, the design technology behind each instrument is vastly different. When the Alnor Dewpointer and Vaisala DM70 instruments are used to measure the dew point of the internal gas volume simultaneously from a pressurized transformer, their differences in dew point measurement have been observed to vary as much as 30 °F. There is minimal scientific research available that focuses on the process of measuring dew point of a gas inside a pressurized transformer, let alone this observed phenomenon. The primary objective of this work was to determine what effect certain factors potentially have on dew point measurements of a transformer's internal gas volume, in hopes of understanding the root cause of this phenomenon. Three factors that were studied include (1) human error, (2) the use of calibrated and out-of-calibration instruments, and (3) the presence of oil vapor gases in the dry air sample, and their subsequent effects on the Q-value of the sampled gas. After completing this portion of testing, none of the selected variables proved to be a direct cause of the observed discrepancies between the two instruments. The secondary objective was to validate the accuracy of each instrument as compared to its respective published range by testing against a known dew point temperature produced by a humidity generator. In a select operating range of -22 °F to -4 °F, both instruments were found to be accurate and within their

  8. Accurate dew-point measurement over a wide temperature range using a quartz crystal microbalance dew-point sensor

    International Nuclear Information System (INIS)

    Kwon, Su-Yong; Kim, Jong-Chul; Choi, Buyng-Il

    2008-01-01

    Quartz crystal microbalance (QCM) dew-point sensors are based on frequency measurement, and so have fast response time, high sensitivity and high accuracy. Recently, we have reported that they have the very convenient attribute of being able to distinguish between supercooled dew and frost from a single scan through the resonant frequency of the quartz resonator as a function of the temperature. In addition to these advantages, by using three different types of heat sinks, we have developed a QCM dew/frost-point sensor with a very wide working temperature range (−90 °C to 15 °C). The temperature of the quartz surface can be obtained effectively by measuring the temperature of the quartz crystal holder and using temperature compensation curves (which showed a high level of repeatability and reproducibility). The measured dew/frost points showed very good agreement with reference values and were within ±0.1 °C over the whole temperature range

  9. Temporal trends in United States dew point temperatures

    Science.gov (United States)

    Robinson, Peter J.

    2000-07-01

    In this study, hourly data for the 1951-1990 period for 178 stations in the coterminous United States were used to establish temporal trends in dew point temperature. Although the data had been quality controlled previously (Robinson, 1998. Monthly variations of dew point temperatures in the coterminous United States. International Journal of Climatology 18: 1539-1556), comparisons of values between nearby stations suggested that instrumental changes, combined with locational changes, may have modified the results by as much as 1°C during the 40-year period. Nevertheless, seasonally averaged results indicated an increase over much of the area, of slightly over 1°C/100 years in spring and autumn, slightly less than this in summer. Winter displayed a drying of over 1°C/100 years. When only the 1961-1990 period was considered, the patterns were similar and trends increased by approximately 1-2°C/100 years, except in autumn, which displayed a slight drying. Analyses for specific stations indicated periods of both increasing and decreasing Td, the change between them varying with observation hour. No single change point was common over a wide area, although January commonly indicated maximum values early in the period in the east and west, and much later in the north-central portion. Rates of increase were generally higher in daytime than at night, especially in summer. Investigation of the inter-decadal differences in dew point, as a function of wind conditions, indicated that changes during calm conditions were commonly similar in magnitude to that of the overall average changes, suggesting an important role for the local hydrologic cycle in driving changes. Other inter-decadal changes could be attributed to the changes in the frequency and moisture content of invading air-streams. This was particularly clear for the changes in north-south flow in the interior.

  10. Using ANFIS for selection of more relevant parameters to predict dew point temperature

    International Nuclear Information System (INIS)

    Mohammadi, Kasra; Shamshirband, Shahaboddin; Petković, Dalibor; Yee, Por Lip; Mansor, Zulkefli

    2016-01-01

    Highlights: • ANFIS is used to select the most relevant variables for dew point temperature prediction. • Two cities from the central and south central parts of Iran are selected as case studies. • Influence of 5 parameters on dew point temperature is evaluated. • Appropriate selection of input variables has a notable effect on prediction. • Considering the most relevant combination of 2 parameters would be more suitable. - Abstract: In this research work, for the first time, the adaptive neuro fuzzy inference system (ANFIS) is employed to propose an approach for identifying the most significant parameters for prediction of daily dew point temperature (T_d_e_w). The ANFIS process for variable selection is implemented, which includes a number of ways to recognize the parameters offering favorable predictions. According to the physical factors influencing the dew formation, 8 variables of daily minimum, maximum and average air temperatures (T_m_i_n, T_m_a_x and T_a_v_g), relative humidity (R_h), atmospheric pressure (P), water vapor pressure (V_P), sunshine hour (n) and horizontal global solar radiation (H) are considered to investigate their effects on T_d_e_w. The used data include 7 years daily measured data of two Iranian cities located in the central and south central parts of the country. The results indicate that despite climate difference between the considered case studies, for both stations, V_P is the most influential variable while R_h is the least relevant element. Furthermore, the combination of T_m_i_n and V_P is recognized as the most influential set to predict T_d_e_w. The conducted examinations show that there is a remarkable difference between the errors achieved for most and less relevant input parameters, which highlights the importance of appropriate selection of input parameters. The use of more than two inputs may not be advisable and appropriate; thus, considering the most relevant combination of 2 parameters would be more suitable

  11. Pressure-Drop Considerations in the Characterization of Dew-Point Transfer Standards at High Temperatures

    Science.gov (United States)

    Mitter, H.; Böse, N.; Benyon, R.; Vicente, T.

    2012-09-01

    During calibration of precision optical dew-point hygrometers (DPHs), it is usually necessary to take into account the pressure drop induced by the gas flow between the "point of reference" and the "point of use" (mirror or measuring head of the DPH) either as a correction of the reference dew-point temperature or as part of the uncertainty estimation. At dew-point temperatures in the range of ambient temperature and below, it is sufficient to determine the pressure drop for the required gas flow, and to keep the volumetric flow constant during the measurements. In this case, it is feasible to keep the dry-gas flow into the dew-point generator constant or to measure the flow downstream the DPH at ambient temperature. In normal operation, at least one DPH in addition to the monitoring DPH are used, and this operation has to be applied to each instrument. The situation is different at high dew-point temperatures up to 95 °C, the currently achievable upper limit reported in this paper. With increasing dew-point temperatures, the reference gas contains increasing amounts of water vapour and a constant dry-gas flow will lead to a significant enhanced volume flow at the conditions at the point of use, and therefore, to a significantly varying pressure drop depending on the applied dew-point temperature. At dew-point temperatures above ambient temperature, it is also necessary to heat the reference gas and the mirror head of the DPH sufficiently to avoid condensation which will additionally increase the volume flow and the pressure drop. In this paper, a method is provided to calculate the dry-gas flow rate needed to maintain a known wet-gas flow rate through a chilled mirror for a range of temperature and pressures.

  12. Investigation of the dew-point temperature scale maintained at the MIKES

    Science.gov (United States)

    Heinonen, Martti

    1999-01-01

    For the investigation of the dew-point temperature scale realized by the MIKES primary dew-point generator, a two-pressure generator and a dew-point indicator based on condensation in a cooled coil were constructed and tested. In addition, a chilled mirror hygrometer was validated by means of an uncertainty analysis. The comparison of these systems was focused on the dew-point temperature range from 0957-0233/10/1/010/img1 to 0957-0233/10/1/010/img2 but measurements were made up to 0957-0233/10/1/010/img3. The generator systems were compared using a dew-point comparator based on two relative humidity sensors. According to the results of the comparisons, the differences between the measurement systems were less than 0957-0233/10/1/010/img4, while the expanded uncertainty of the MIKES generator was between 0957-0233/10/1/010/img5 and 0957-0233/10/1/010/img6. The uncertainty of the other systems was from 0957-0233/10/1/010/img7 to 0957-0233/10/1/010/img8. It was concluded that the dew-point temperature scale was not dependent on the realization method.

  13. Dew point temperature affects ascospore release of allergenic genus Leptosphaeria

    Science.gov (United States)

    Sadyś, Magdalena; Kaczmarek, Joanna; Grinn-Gofron, Agnieszka; Rodinkova, Victoria; Prikhodko, Alex; Bilous, Elena; Strzelczak, Agnieszka; Herbert, Robert J.; Jedryczka, Malgorzata

    2018-01-01

    The genus Leptosphaeria contains numerous fungi that cause the symptoms of asthma and also parasitize wild and crop plants. In search of a robust and universal forecast model, the ascospore concentration in air was measured and weather data recorded from 1 March to 31 October between 2006 and 2012. The experiment was conducted in three European countries of the temperate climate, i.e., Ukraine, Poland, and the UK. Out of over 150 forecast models produced using artificial neural networks (ANNs) and multivariate regression trees (MRTs), we selected the best model for each site, as well as for joint two-site combinations. The performance of all computed models was tested against records from 1 year which had not been used for model construction. The statistical analysis of the fungal spore data was supported by a comprehensive study of both climate and land cover within a 30-km radius from the air sampler location. High-performance forecasting models were obtained for individual sites, showing that the local micro-climate plays a decisive role in biology of the fungi. Based on the previous epidemiological studies, we hypothesized that dew point temperature (DPT) would be a critical factor in the models. The impact of DPT was confirmed only by one of the final best neural models, but the MRT analyses, similarly to the Spearman's rank test, indicated the importance of DPT in all but one of the studied cases and in half of them ranked it as a fundamental factor. This work applies artificial neural modeling to predict the Leptosphaeria airborne spore concentration in urban areas for the first time.

  14. Dew point temperature affects ascospore release of allergenic genus Leptosphaeria

    Science.gov (United States)

    Sadyś, Magdalena; Kaczmarek, Joanna; Grinn-Gofron, Agnieszka; Rodinkova, Victoria; Prikhodko, Alex; Bilous, Elena; Strzelczak, Agnieszka; Herbert, Robert J.; Jedryczka, Malgorzata

    2018-06-01

    The genus Leptosphaeria contains numerous fungi that cause the symptoms of asthma and also parasitize wild and crop plants. In search of a robust and universal forecast model, the ascospore concentration in air was measured and weather data recorded from 1 March to 31 October between 2006 and 2012. The experiment was conducted in three European countries of the temperate climate, i.e., Ukraine, Poland, and the UK. Out of over 150 forecast models produced using artificial neural networks (ANNs) and multivariate regression trees (MRTs), we selected the best model for each site, as well as for joint two-site combinations. The performance of all computed models was tested against records from 1 year which had not been used for model construction. The statistical analysis of the fungal spore data was supported by a comprehensive study of both climate and land cover within a 30-km radius from the air sampler location. High-performance forecasting models were obtained for individual sites, showing that the local micro-climate plays a decisive role in biology of the fungi. Based on the previous epidemiological studies, we hypothesized that dew point temperature (DPT) would be a critical factor in the models. The impact of DPT was confirmed only by one of the final best neural models, but the MRT analyses, similarly to the Spearman's rank test, indicated the importance of DPT in all but one of the studied cases and in half of them ranked it as a fundamental factor. This work applies artificial neural modeling to predict the Leptosphaeria airborne spore concentration in urban areas for the first time.

  15. An Investigation of the Relation Between Contact Thermometry and Dew-Point Temperature Realization

    Science.gov (United States)

    Benyon, R.; Böse, N.; Mitter, H.; Mutter, D.; Vicente, T.

    2012-09-01

    Precision optical dew-point hygrometers are the most commonly used transfer standards for the comparison of dew-point temperature realizations at National Metrology Institutes (NMIs) and for disseminating traceability to calibration laboratories. These instruments have been shown to be highly reproducible when properly used. In order to obtain the best performance, the resistance of the platinum resistance thermometer (PRT) embedded in the mirror is usually measured with an external, traceable resistance bridge or digital multimeter. The relation between the conventional calibration of miniature PRTs, prior to their assembly in the mirrors of state-of-the-art optical dew-point hygrometers and their subsequent calibration as dew-point temperature measurement devices, has been investigated. Standard humidity generators of three NMIs were used to calibrate hygrometers of different designs, covering the dew-point temperature range from -75 °C to + 95 °C. The results span more than a decade, during which time successive improvements and modifications were implemented by the manufacturer. The findings are presented and discussed in the context of enabling the optimum use of these transfer standards and as a basis for determining contributions to the uncertainty in their calibration.

  16. Observed changes in relative humidity and dew point temperature in coastal regions of Iran

    Science.gov (United States)

    Hosseinzadeh Talaee, P.; Sabziparvar, A. A.; Tabari, Hossein

    2012-12-01

    The analysis of trends in hydroclimatic parameters and assessment of their statistical significance have recently received a great concern to clarify whether or not there is an obvious climate change. In the current study, parametric linear regression and nonparametric Mann-Kendall tests were applied for detecting annual and seasonal trends in the relative humidity (RH) and dew point temperature ( T dew) time series at ten coastal weather stations in Iran during 1966-2005. The serial structure of the data was considered, and the significant serial correlations were eliminated using the trend-free pre-whitening method. The results showed that annual RH increased by 1.03 and 0.28 %/decade at the northern and southern coastal regions of the country, respectively, while annual T dew increased by 0.29 and 0.15°C per decade at the northern and southern regions, respectively. The significant trends were frequent in the T dew series, but they were observed only at 2 out of the 50 RH series. The results showed that the difference between the results of the parametric and nonparametric tests was small, although the parametric test detected larger significant trends in the RH and T dew time series. Furthermore, the differences between the results of the trend tests were not related to the normality of the statistical distribution.

  17. Sensitivity of a soil-plant-atmosphere model to changes in air temperature, dew point temperature, and solar radiation

    Energy Technology Data Exchange (ETDEWEB)

    Luxmoore, R.J. (Oak Ridge National Lab.,TN); Stolzy, J.L.; Holdeman, J.T.

    1981-01-01

    Air temperature, dew point temperature and solar radiation were independently varied in an hourly soil-plant-atmosphere model in a sensitivity analysis of these parameters. Results suggested that evapotranspiration in eastern Tennessee is limited more by meteorological conditions that determine the vapor-pressure gradient than by the necessary energy to vaporize water within foliage. Transpiration and soil water drainage were very sensitive to changes in air and dew point temperature and to solar radiation under low atmospheric vapor-pressure deficit conditions associated with reduced air temperature. Leaf water potential and stomatal conductance were reduced under conditions having high evapotranspiration. Representative air and dew point temperature input data for a particular application are necessary for satisfactory results, whereas irradiation may be less well characterized for applications with high atmospheric vapor-pressure deficit. The effects of a general rise in atmospheric temperature on forest water budgets are discussed.

  18. Estimation of dew point temperature using neuro-fuzzy and neural network techniques

    Science.gov (United States)

    Kisi, Ozgur; Kim, Sungwon; Shiri, Jalal

    2013-11-01

    This study investigates the ability of two different artificial neural network (ANN) models, generalized regression neural networks model (GRNNM) and Kohonen self-organizing feature maps neural networks model (KSOFM), and two different adaptive neural fuzzy inference system (ANFIS) models, ANFIS model with sub-clustering identification (ANFIS-SC) and ANFIS model with grid partitioning identification (ANFIS-GP), for estimating daily dew point temperature. The climatic data that consisted of 8 years of daily records of air temperature, sunshine hours, wind speed, saturation vapor pressure, relative humidity, and dew point temperature from three weather stations, Daego, Pohang, and Ulsan, in South Korea were used in the study. The estimates of ANN and ANFIS models were compared according to the three different statistics, root mean square errors, mean absolute errors, and determination coefficient. Comparison results revealed that the ANFIS-SC, ANFIS-GP, and GRNNM models showed almost the same accuracy and they performed better than the KSOFM model. Results also indicated that the sunshine hours, wind speed, and saturation vapor pressure have little effect on dew point temperature. It was found that the dew point temperature could be successfully estimated by using T mean and R H variables.

  19. Trends in temperature and dew point at the summit of Mount Washington, New Hampshire, 1935-2004.

    Science.gov (United States)

    Grant, A. N.; Pszenny, A. A.; Fischer, E. V.

    2005-05-01

    Dry and wet bulb temperatures from sling psychrometer measurements taken every six hours from 1935 to 2004 at the summit of Mount Washington, located at 44 °16'N, 71 °18'W, 1914 m ASL have recently been digitized. Annual temperature has increased by 0.3°C, and annual dew point has decreased by 0.4°C over this 70-year period. Synoptic temperature has increased most in spring and winter, changing by 1.0°C and 0.5°C, respectively, while it has decreased slightly in summer and fall. Dew point has decreased in fall, summer, and winter, 0.9°C, 0.5°C, and 0.4°C respectively, and increased by 0.1°C in spring. Preliminary analysis suggests that some of the larger trends in winter and spring may be statistically significant; results of Monte Carlo simulations will be reported. Changes in dew point may be attributed to two factors. Decreasing dew points are expected if the temperature increases but the amount of water vapor present stays the same. Alternatively, lower dew points could be indicative of the presence of drier air. Other dew point climatologies of the continental United States for the second half of the century have shown mixed results, with increased dew points evident at some stations, decreased dew points at others, and no clear regional patterns.

  20. Pipeline drying using dehumidified air with low dew point temperature

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Syed Younus; Gandhidasan, P.; Al-Farayedhi, A.A. [King Fahd Univ. of Petroleum and Minerals, Mechanical Engineering Dept., Dhahran (Saudi Arabia)

    1998-05-01

    The presence of humidity may be detrimental to the operation of pipelines transporting natural gas or other petroleum products. In particular conditions water solidifies or reacts chemically with hydrocarbons, forming hydrates. Such crystalline substances may cause obstruction of the lines and damage the equipment of the relevant facilities. A procedure for predicting the performance of drying a pipeline using dehumidified air with a low dew point is described in this paper. The mathematical model estimates the time required for the complete removal of moisture in the pipeline for the given operating conditions with simplified assumptions. The governing equations are solved analytically as well as numerically and the results are briefly discussed in the paper. (Author)

  1. Consistency of the national realization of dew-point temperature using NIS standard humidity generators

    Directory of Open Access Journals (Sweden)

    El-Galil Doaa Abd

    2017-01-01

    Full Text Available A comparison of two standard humidity generators (two-temperature (2-T and one-temperature (1-T generators that are developed by the National Institute for Standards (NIS has been performed using a transfer standard chilled-mirror hygrometer and measurement procedures to realize dew-point temperature Td in the range from −50 °C to 0 °C. The main objective of this comparison was to compare the realizations of dew-point temperature and to establish the level of consistency between the two generators. For a level of consistency between two measurements, it is expressed by the difference between the measured values, m1 − m2, and the expanded pair uncertainty of this difference Up [1]. The comparison measurements revealed dew-point temperature differences of 0.02 °C and 0.07 °C with expanded pair uncertainties of ±0.09 °C and ±0.15 °C.

  2. Development of Bioclimatic Design Tool for Oman Using Dry Bulb and Dew Point Temperatures Open Database

    Directory of Open Access Journals (Sweden)

    Nasser Al-Azri

    2017-06-01

    Full Text Available Bioclimatic charts are used by engineers and architects in implementing passive cooling systems and architectural optimization with respect to natural air conditioning. Conventionally, the development of these charts is based on the availability of typical meteorological year which requires a record of meteorological data that are rarely available in sufficient amounts. Bioclimatic charts in Oman were developed earlier by the authors for limited locations based on the available typical meteorological years. Using dry bulb and dew point temperatures only, bioclimatic charts are developed for Adam, Buraimi, Ibra, Muscat, Nizwa, Rustaq, Saiq, Salalah, Suhar and Sur. These charts are better representative of bioclimatic trends since their development is mainly based on the relevant parameters, namely dry bulb temperature and dew point.

  3. The dew point temperature as a criterion for optimizing the operating conditions of proton exchange membrane fuel cells

    DEFF Research Database (Denmark)

    Berning, Torsten

    2012-01-01

    In this article an analytical method to calculate the dew point temperatures of the anode and cathode exit gas streams of a proton exchange membrane fuel cell is developed. The results of these calculations are used to create diagrams that show the dew point temperatures as function of the operat...... for conventional flow field plates. The diagrams presented here are created for completely dry inlet gases, but they can be easily corrected for a nonzero inlet relative humidity....

  4. The effect of water contamination on the dew-point temperature scale realization with humidity generators

    Science.gov (United States)

    Vilbaste, M.; Heinonen, M.; Saks, O.; Leito, I.

    2013-08-01

    The purpose of this paper is to study the effect of contaminated water in the context of humidity generators. Investigation of different methods to determine the drop in dew-point temperature due to contamination and experiments on actual contamination rates are reported. Different methods for calculating the dew-point temperature effect from electrical conductivity and density measurements are studied with high-purity water and aqueous solutions of NaCl and LiCl. The outcomes of the calculation methods are compared with the results of direct humidity measurements. The results show that the often applied Raoult's law based calculation method is in good agreement with other methods. For studying actual contamination, water samples were kept in glass, plastic, copper and stainless-steel vessels for up to 13 months to investigate natural ionic and organic contamination in vessels with different wall materials. The amount of ionic contamination was found to be higher in copper and glass vessels than in stainless-steel and plastic vessels. The amount of organic contamination was found to be highest in the plastic vessel. In all the cases, however, the corresponding drop in dew-point temperature due to natural contamination was found to be below 0.1 mK. The largest rate of change of dew-point temperature was 26 µK/month. Thus, if proper cleanness is maintained in a humidity generator the effect of contamination of water in the saturator is insignificant compared with the major uncertainty components even in the most accurate generators today.

  5. A new steel with good low-temperature sulfuric acid dew point corrosion resistance

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, X.Q.; Li, X.G. [Corrosion and Protection Center, University of Science and Technology Beijing (China); Key Laboratory of Corrosion and Protection (Ministry of Education), Beijing (China); Sun, F.L. [Corrosion and Protection Center, University of Science and Technology Beijing (China); Lv, S.J. [Corrosion and Protection Center, University of Science and Technology Beijing (China); Equipment and Power Department, Shijiazhuang Refine and Chemical Company Limited, SINOPEC, Shijiazhuang (China)

    2012-07-15

    In this work, new steels (1, 2, and 3) were developed for low-temperature sulfuric acid dew point corrosion. The mass loss rate, macro- and micro-morphologies and compositions of corrosion products of new steels in 10, 30, and 50% H{sub 2}SO{sub 4} solutions at its corresponding dew points were investigated by immersion test, scanning electron microscopy (SEM) and energy-dispersive spectrometry (EDS). The results indicated that mass loss rate of all the tested steels first strongly increased and then decreased as H{sub 2}SO{sub 4} concentration increased, which reached maximum at 30%. Corrosion resistance of 2 steel is the best among all specimens due to its fine and homogeneous morphologies of corrosion products. The electrochemical corrosion properties of new steels in 10 and 30% H{sub 2}SO{sub 4} solutions at its corresponding dew points were studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The results demonstrated that corrosion resistance of 2 steel is the best among all the experimental samples due to its lowest corrosion current density and highest charge transfer resistance, which is consistent with the results obtained from immersion tests. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Laser Dew-Point Hygrometer

    Science.gov (United States)

    Matsumoto, Shigeaki; Toyooka, Satoru

    1995-01-01

    A rough-surface-type automatic dew-point hygrometer was developed using a laser diode and an optical fiber cable. A gold plate with 0.8 µ m average surface roughness was used as a surface for deposition of dew to facilitate dew deposition and prevent supersaturation of water vapor at the dew point. It was shown experimentally that the quantity of dew deposited can be controlled to be constant at any predetermined level, and is independent of the dew point to be measured. The dew points were measured in the range from -15° C to 54° C in which the temperature ranged from 0° C to 60° C. The measurement error of the dew point was ±0.5° C which was equal to below ±2% in relative humidity in the above dew-point range.

  7. Development of the High-Temperature Dew-Point Generator Over the Past 15 Years

    Science.gov (United States)

    Bosma, R.; Nielsen, J.; Peruzzi, A.

    2017-10-01

    At VSL a humidity generator was designed and constructed in the early 1990s. This generator was of the re-circulating-single-pressure type. Over the years, the generator has been thoroughly revised and several critical components have been replaced. Among others the pre-saturator and the change from re-circulation to single-pass mode. Validating experiments showed that the range of the new setup could be extended from 70 {°}C to 95 {°}C dew-point temperature, and the last modification allows an uncertainty of 0.048 {°}C (k = 2) at the maximum temperature. In 2009 the setup was used in the Euramet-T-K8 humidity intercomparison at temperatures up to 95 {°}C. In the period from 2003 to 2015, four state-of-the-art chilled mirror hygrometers were regularly calibrated with the generator. One of these was also calibrated with the primary dew-point standards of several other European National Metrology Institutes, which made it possible to link the VSL generator to the generators used in these institutes. An analysis of the results of these calibrations shows an agreement in calibration capabilities within 0.01 {°}C with PTB and NPL.

  8. Monthly variations of dew point temperature in the coterminous United States

    Science.gov (United States)

    Robinson, Peter J.

    1998-11-01

    The dew point temperature, Td, data from the surface airways data set of the U.S. National Climatic Data Center were used to develop a basic dew point climatology for the coterminous United States. Quality control procedures were an integral part of the analysis. Daily Td, derived as the average of eight observations at 3-hourly intervals, for 222 stations for the 1961-1990 period were used. The annual and seasonal pattern of average values showed a clear south-north decrease in the eastern portion of the nation, a trend which was most marked in winter. In the west, values decreased inland from the Pacific Coast. Inter-annual variability was generally low when actual mean values were high. A cluster analysis suggested that the area could be divided into six regions, two oriented north-south in the west, four aligned east-west in the area east of the Rocky Mountains. Day-to-day variability was low in all seasons in the two western clusters, but showed a distinct winter maximum in the east. This was explained in broad terms by consideration of air flow regimes, with the Pacific Ocean and the Gulf of Mexico acting as the major moisture sources. Comparison of values for pairs of nearby stations suggested that Td was rather insensitive to local moisture sources. Analysis of the patterns of occurrence of dew points exceeding the 95th percentile threshold indicated that extremes in summer tend to be localized and short-lived, while in winter they are more widespread and persistent.

  9. Hourly predictive Levenberg-Marquardt ANN and multi linear regression models for predicting of dew point temperature

    Science.gov (United States)

    Zounemat-Kermani, Mohammad

    2012-08-01

    In this study, the ability of two models of multi linear regression (MLR) and Levenberg-Marquardt (LM) feed-forward neural network was examined to estimate the hourly dew point temperature. Dew point temperature is the temperature at which water vapor in the air condenses into liquid. This temperature can be useful in estimating meteorological variables such as fog, rain, snow, dew, and evapotranspiration and in investigating agronomical issues as stomatal closure in plants. The availability of hourly records of climatic data (air temperature, relative humidity and pressure) which could be used to predict dew point temperature initiated the practice of modeling. Additionally, the wind vector (wind speed magnitude and direction) and conceptual input of weather condition were employed as other input variables. The three quantitative standard statistical performance evaluation measures, i.e. the root mean squared error, mean absolute error, and absolute logarithmic Nash-Sutcliffe efficiency coefficient ( {| {{{Log}}({{NS}})} |} ) were employed to evaluate the performances of the developed models. The results showed that applying wind vector and weather condition as input vectors along with meteorological variables could slightly increase the ANN and MLR predictive accuracy. The results also revealed that LM-NN was superior to MLR model and the best performance was obtained by considering all potential input variables in terms of different evaluation criteria.

  10. Trends in extremes of temperature, dew point, and precipitation from long instrumental series from central Europe

    Science.gov (United States)

    Kürbis, K.; Mudelsee, M.; Tetzlaff, G.; Brázdil, R.

    2009-09-01

    For the analysis of trends in weather extremes, we introduce a diagnostic index variable, the exceedance product, which combines intensity and frequency of extremes. We separate trends in higher moments from trends in mean or standard deviation and use bootstrap resampling to evaluate statistical significances. The application of the concept of the exceedance product to daily meteorological time series from Potsdam (1893 to 2005) and Prague-Klementinum (1775 to 2004) reveals that extremely cold winters occurred only until the mid-20th century, whereas warm winters show upward trends. These changes were significant in higher moments of the temperature distribution. In contrast, trends in summer temperature extremes (e.g., the 2003 European heatwave) can be explained by linear changes in mean or standard deviation. While precipitation at Potsdam does not show pronounced trends, dew point does exhibit a change from maximum extremes during the 1960s to minimum extremes during the 1970s.

  11. Global Validation of MODIS Atmospheric Profile-Derived Near-Surface Air Temperature and Dew Point Estimates

    Science.gov (United States)

    Famiglietti, C.; Fisher, J.; Halverson, G. H.

    2017-12-01

    This study validates a method of remote sensing near-surface meteorology that vertically interpolates MODIS atmospheric profiles to surface pressure level. The extraction of air temperature and dew point observations at a two-meter reference height from 2001 to 2014 yields global moderate- to fine-resolution near-surface temperature distributions that are compared to geographically and temporally corresponding measurements from 114 ground meteorological stations distributed worldwide. This analysis is the first robust, large-scale validation of the MODIS-derived near-surface air temperature and dew point estimates, both of which serve as key inputs in models of energy, water, and carbon exchange between the land surface and the atmosphere. Results show strong linear correlations between remotely sensed and in-situ near-surface air temperature measurements (R2 = 0.89), as well as between dew point observations (R2 = 0.77). Performance is relatively uniform across climate zones. The extension of mean climate-wise percent errors to the entire remote sensing dataset allows for the determination of MODIS air temperature and dew point uncertainties on a global scale.

  12. Measurement Uncertainty of Dew-Point Temperature in a Two-Pressure Humidity Generator

    Science.gov (United States)

    Martins, L. Lages; Ribeiro, A. Silva; Alves e Sousa, J.; Forbes, Alistair B.

    2012-09-01

    This article describes the measurement uncertainty evaluation of the dew-point temperature when using a two-pressure humidity generator as a reference standard. The estimation of the dew-point temperature involves the solution of a non-linear equation for which iterative solution techniques, such as the Newton-Raphson method, are required. Previous studies have already been carried out using the GUM method and the Monte Carlo method but have not discussed the impact of the approximate numerical method used to provide the temperature estimation. One of the aims of this article is to take this approximation into account. Following the guidelines presented in the GUM Supplement 1, two alternative approaches can be developed: the forward measurement uncertainty propagation by the Monte Carlo method when using the Newton-Raphson numerical procedure; and the inverse measurement uncertainty propagation by Bayesian inference, based on prior available information regarding the usual dispersion of values obtained by the calibration process. The measurement uncertainties obtained using these two methods can be compared with previous results. Other relevant issues concerning this research are the broad application to measurements that require hygrometric conditions obtained from two-pressure humidity generators and, also, the ability to provide a solution that can be applied to similar iterative models. The research also studied the factors influencing both the use of the Monte Carlo method (such as the seed value and the convergence parameter) and the inverse uncertainty propagation using Bayesian inference (such as the pre-assigned tolerance, prior estimate, and standard deviation) in terms of their accuracy and adequacy.

  13. Consistency of the National Realization of Dew-Point Temperature Using Standard Humidity Generators

    Science.gov (United States)

    Benyon, R.; Vicente, T.

    2012-09-01

    The comparison of two high-range standard humidity generators used by Instituto Nacional de Técnica Aeroespacial to realize dew-point temperature in the range from -10 °C to +95 °C has been performed using state-of-the art transfer standards and measurement procedures, over their overlapping range from -10 °C to +75 °C. The aim of this study is to investigate the level of agreement between the two generators, to determine any bias, and to quantify the level of consistency of the two realizations. The measurement procedures adopted to minimize the effect of the influence factors due to the transfer standards are described, and the results are discussed in the context of the declared calibration and measurement capabilities (CMCs).

  14. Instrument air dew point requirements -- 108-P, L, K

    International Nuclear Information System (INIS)

    Fairchild, P.N.

    1994-01-01

    The 108 Building dew point analyzers measure dew point at atmospheric pressure. Existing 108 Roundsheets state the maximum dew point temperature shall be less than -50 F. After repeatedly failing to maintain a -50 F dew point temperature Reactor Engineering researched the basis for the existing limit. This report documents the results of the study and provides technical justification for a new maximum dew point temperature of -35 F at atmospheric pressure as read by the 108 building dew point analyzers

  15. Flue gas heat recovery operating below the dew point and its utilisation for low temperature heating installations

    Energy Technology Data Exchange (ETDEWEB)

    Wilsdorf, J.

    1986-11-01

    This paper deals at first with the characteristics of two principal systems for the flue gas heat recovery by reducing the temperature below the dew point. With test results on experimental plants are shown the typical differences between surface and direct contact heat exchange. A second part informs about experiences from the application for low temperature heating installations, especially about thermodynamics condensate quality and technical design. The possible increasing of the efficiency ranges between 10 to 20 per cent.

  16. Effect of the temperature and dew point of the decarburization process on the oxide subscale of a 3% silicon steel

    Energy Technology Data Exchange (ETDEWEB)

    Cesar, Maria das Gracas M.M. E-mail: gracamelo@acesita.com.br; Mantel, Marc J

    2003-01-01

    The oxide subscale formed on the decarburization annealing of 3% Si-Fe was investigated using microscopy and spectroscopy techniques. It was found that the morphology as well as the molecular structure of the subscale are affected by temperature and dew point. The results suggest that there is an optimum level of internal oxidation and an optimum fayalite/silica ratio in the subscale to achieve a oriented grain silicon steel having a continuous and smooth ceramic film and low core loss.

  17. Dew Point

    OpenAIRE

    Goldsmith, Shelly

    1999-01-01

    Dew Point was a solo exhibition originating at PriceWaterhouseCoopers Headquarters Gallery, London, UK and toured to the Centre de Documentacio i Museu Textil, Terrassa, Spain and Gallery Aoyama, Tokyo, Japan.

  18. Wet-bulb, dew point, and air temperature trends in Spain

    Science.gov (United States)

    Moratiel, R.; Soriano, B.; Centeno, A.; Spano, D.; Snyder, R. L.

    2017-10-01

    This study analyses trends of mean ( T m), maximum ( T x), minimum ( T n), dew point ( T d), and wet-bulb temperatures ( T w) on an annual, seasonal, and monthly time scale over Spain during the period 1981-2010. The main purpose was to determine how temperature and humidity changes are impacting on T w, which is probably a better measure of climate change than temperature alone. In this study, 43 weather stations were used to detect data trends using the nonparametric Mann-Kendall test and the Sen method to estimate the slope of trends. Significant linear trends observed for T m, T x, and T n versus year were 56, 58, and 47 % of the weather stations, respectively, with temperature ranges between 0.2 and 0.4 °C per decade. The months with bigger trends were April, May, June, and July with the highest trend for T x. The spatial behaviour of T d and T w was variable, with various locations showing trends from -0.6 to +0.3 °C per decade for T d and from -0.4 to +0.5 °C per decade for T w. Both T d and T w showed negative trends for July, August, September, November, and December. Comparing the trends versus time of each variable versus each of the other variables exhibited poor relationships, which means you cannot predict the trend of one variable from the trend of another variable. The trend of T x was not related to the trend of T n. The trends of T x, T m, and T n versus time were unrelated to the trends versus time of either T d or T w. The trend of T w showed a high coefficient of determination with the trend of T d with an annual value of R 2 = 0.86. Therefore, the T w trend is more related to changes in humidity than temperature.

  19. Investigation of the Equivalence of National Dew-Point Temperature Realizations in the -50 °C to + 20 °C Range

    Science.gov (United States)

    Heinonen, Martti; Anagnostou, Miltiadis; Bell, Stephanie; Stevens, Mark; Benyon, Robert; Bergerud, Reidun Anita; Bojkovski, Jovan; Bosma, Rien; Nielsen, Jan; Böse, Norbert; Cromwell, Plunkett; Kartal Dogan, Aliye; Aytekin, Seda; Uytun, Ali; Fernicola, Vito; Flakiewicz, Krzysztof; Blanquart, Bertrand; Hudoklin, Domen; Jacobson, Per; Kentved, Anders; Lóio, Isabel; Mamontov, George; Masarykova, Alexandra; Mitter, Helmut; Mnguni, Regina; Otych, Jan; Steiner, Anton; Szilágyi Zsófia, Nagyné; Zvizdic, Davor

    2012-09-01

    In the field of humidity quantities, the first CIPM key comparison, CCT-K6 is at its end. The corresponding European regional key comparison, EUROMET.T-K6, was completed in early 2008, about 4 years after the starting initial measurements in the project. In total, 24 NMIs from different countries took part in the comparison. This number includes 22 EURAMET countries, and Russia and South Africa. The comparison covered the dew-point temperature range from -50 °C to +20 °C. It was carried out in three parallel loops, each with two chilled mirror hygrometers as transfer standards in each loop. The comparison scheme was designed to ensure high quality results with evenly spread workload for the participants. It is shown that the standard uncertainty due to the long-term instability was smaller than 0.008 °C in all loops. The standard uncertainties due to links between the loops were found to be smaller than 0.025 °C at -50 °C and 0.010 °C elsewhere. Conclusions on the equivalence of the dew-point temperature standards are drawn on the basis of calculated bilateral degrees of equivalence and deviations from the EURAMET comparison reference values (ERV). Taking into account 16 different primary dew-point realizations and 8 secondary realizations, the results demonstrate the equivalence of a large number of laboratories at an uncertainty level that is better than achieved in other multilateral comparisons so far in the humidity field.

  20. SHORT COMMUNICATION: Recognition of supercooled dew in a quartz crystal microbalance dew-point sensor by slip phenomena

    Science.gov (United States)

    Kwon, Su-Yong; Kim, Jong-Chul; Choi, Byung-Il

    2007-10-01

    Distinguishing between a supercooled dew and frost below 0 °C in dew/frost-point measurements is an important and challenging problem that has not yet been completely solved. This study presents a new method for the recognition of a supercooled dew in a dew/frost-point sensor. A quartz crystal microbalance (QCM) sensor was used as a dew/frost-point sensor to detect a dew and a supercooled dew as well as frost. The slip phenomenon occurring at an interface between the water droplet and the surface of the quartz crystal resonator of the QCM sensor gives a simple and accurate way of distinguishing between a supercooled dew and frost below 0 °C. This method can give a highly accurate measurement of the dew or the frost point without misreading in the dew-point sensor at temperatures below 0 °C.

  1. Calibration of Relative Humidity Sensors using a Dew Point Generator

    OpenAIRE

    Brooks, Milo

    2010-01-01

    A relative humidity sensor can be calibrated using a dew point generator to continuously supply an air stream of known constant humidity and a temperature chamber to control the dew point and ambient temperature.

  2. Evaluation of the Long-Term Stability and Temperature Coefficient of Dew-Point Hygrometers

    Science.gov (United States)

    Benyon, R.; Vicente, T.; Hernández, P.; De Rivas, L.; Conde, F.

    2012-09-01

    The continuous quest for improved specifications of optical dew-point hygrometers has raised customer expectations on the performance of these devices. In the absence of a long calibration history, users with a limited prior experience in the measurement of humidity, place reliance on manufacturer specifications to estimate long-term stability. While this might be reasonable in the case of measurement of electrical quantities, in humidity it can lead to optimistic estimations of uncertainty. This article reports a study of the long-term stability of some hygrometers and the analysis of their performance as monitored through regular calibration. The results of the investigations provide some typical, realistic uncertainties associated with the long-term stability of instruments used in calibration and testing laboratories. Together, these uncertainties can help in establishing initial contributions in uncertainty budgets, as well as in setting the minimum calibration requirements, based on the evaluation of dominant influence quantities.

  3. Study of the influence of the cool-down speed at the dew-point level of the readings of the dew-point temperature; Untersuchungen zum Einfluss der Abkuehlgeschwindigkeit am Taupunktspiegel auf Messwerte der Taupunkttemperatur

    Energy Technology Data Exchange (ETDEWEB)

    Bogoya, J.D. [Univ. Nacional de Colombia (Colombia); Mueller, C. [Inst. fuer Technische Thermodynamik und Kaeltetechnik, Univ. Karlsruhe (Germany); Oellrich, L.R. [Inst. fuer Technische Thermodynamik und Kaeltetechnik, Univ. Karlsruhe (Germany)

    1995-09-01

    The impact of the cool-down speed at the dew-point mirror on the behaviour of the readings of dew-point temperature of nitrogen-water mixtures has been investigated with the focus on mixtures with low water content. For this purpose a commercial dew-point mirror was equipped with a refrigerating device in order to cool the mirror surface. Moreover a data acquisition system was connected for the measurement of the rates of cooling. Via a control valve in the refrigerant cycle rates of cooling of about 1 to 35 C/min could be chosen. With a saturation system saturation conditions could be varied in the pressure range from 5 to 90 bar and in the temperature range from +10 to -15 C. The measuring instrument was continuously supplied with the gas mixture. The measurements were carried out under constant volume flow of the carrier gas. The results are discussed. (orig.) [Deutsch] Der Einfluss der Abkuehlgeschwindigkeit am Taupunktspiegel auf die Lage der Messwerte der Taupunkttemperaturen von Stickstoff/Wasser-Gemischen wurde speziell im Bereich niedriger Wassergehalte untersucht. Dazu wurde ein kommerzieller Taupunktspiegel zur Kuehlung der Spiegeloberflaeche mit einer Kaeltemaschine ausgestattet und eine Messwerterfassung, mit der Abkuehlgeschwindigkeiten ermittelt werden konnte, angeschlossen. Ueber ein Regelventil im Kaeltemittelkreislauf konnten Abkuehlgeschwindigkeiten von ca. 1 bis 35 C/min eingestellt werden. Ueber eine Saettigungsanlage wurden Saettigungsbedingungen im Druckbereich von 5 bis 90 bar und im Temperaturbereich von +10 bis -15 C variiert und das Messgeraet kontinuierlich mit Gasgemisch versorgt. Die Messungen wurden bei konstantem Volumenstrom des Traegergases durchgefuehrt. Die Messergebisse werden diskutiert. (orig.)

  4. Future PMPs Estimation in Korea under AR5 RCP 8.5 Climate Change Scenario: Focus on Dew Point Temperature Change

    Science.gov (United States)

    Okjeong, Lee; Sangdan, Kim

    2016-04-01

    According to future climate change scenarios, future temperature is expected to increase gradually. Therefore, it is necessary to reflect the effects of these climate changes to predict Probable Maximum Precipitations (PMPs). In this presentation, PMPs will be estimated with future dew point temperature change. After selecting 174 major storm events from 1981 to 2005, new PMPs will be proposed with respect to storm areas (25, 100, 225, 400, 900, 2,025, 4,900, 10,000 and 19,600 km2) and storm durations (1, 2, 4, 6, 8, 12, 18, 24, 48 and 72 hours) using the Korea hydro-meteorological method. Also, orographic transposition factor will be applied in place of the conventional terrain impact factor which has been used in previous Korean PMPs estimation reports. After estimating dew point temperature using future temperature and representative humidity information under the Korea Meteorological Administration AR5 RCP 8.5, changes in the PMPs under dew point temperature change will be investigated by comparison with present and future PMPs. This research was supported by a grant(14AWMP-B082564-01) from Advanced Water Management Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government.

  5. Growth responses of male broilers subjected to increasing air velocities at high ambient temperatures and a high dew point.

    Science.gov (United States)

    Dozier, W A; Lott, B D; Branton, S L

    2005-06-01

    This study examined live performance responses of male broilers to increasing air velocity of 120 and 180 m/min reared under high cyclic temperatures (25-35-25 degrees C) with a 23 degrees C dew point from 21 to 49 d. Birds were reared in an environmental facility containing 2 wind tunnels (4 pens/tunnel) and 6 floor pens (control). At 21 d, 53 birds were placed in each pen of the wind tunnels and control group, respectively, and growth performance was determined weekly. Increasing air velocity from 120 to 180 m/min improved BW and BW gain from 29 to 35, 36 to 42, and 43 to 49 d of age leading to a cumulative advantage of 287 g in BW gain and a 10-point difference in feed conversion from 21 to 49 d of age. Subjecting birds to air velocity improved growth rate, feed consumption, and feed conversion at each weekly interval from 28 to 49 d over the control birds. These results indicate that male broilers approximating 2.0 to 3.0 kg respond to an air velocity of 180 m/min when exposed to high cyclic temperatures.

  6. Vertical profiles of ozone, carbon monoxide, and dew-point temperature obtained during GTE/CITE 1, October-November 1983. [Chemical Instrumentation Test and Evaluation

    Science.gov (United States)

    Fishman, Jack; Gregory, Gerald L.; Sachse, Glen W.; Beck, Sherwin M.; Hill, Gerald F.

    1987-01-01

    A set of 14 pairs of vertical profiles of ozone and carbon monoxide, obtained with fast-response instrumentation, is presented. Most of these profiles, which were measured in the remote troposphere, also have supporting fast-response dew-point temperature profiles. The data suggest that the continental boundary layer is a source of tropospheric ozone, even in October and November, when photochemical activity should be rather small. In general, the small-scale vertical variability between CO and O3 is in phase. At low latitudes this relationship defines levels in the atmosphere where midlatitude air is being transported to lower latitudes, since lower dew-point temperatures accompany these higher CO and O3 concentrations. A set of profiles which is suggestive of interhemispheric transport is also presented. Independent meteorological analyses support these interpretations.

  7. STUDY ON THE DEW POINT TEMPERATURE IN AREAS WITH SUPERFICIAL LIMESTONE UNDERGROUND ENVIRONMENT (SCREE IN THE GHIMBAV AREA, LEAOTA MOUNTAINS, 2014

    Directory of Open Access Journals (Sweden)

    Magdalin-Leonard Dorobăţ

    2015-07-01

    Full Text Available The dew point of a mixture of a gas (air and the water vapors represents the temperature at which the cold air becomes saturated in water vapors and they condensate. Sometimes, especially in colder periods, it is more revealing regarding the water quantity in the air as vapors, than the relative humidity indicator. The field observations have shown that, always, in the surveys in the ecologic stationaries I have installed in limestone scree in Leaota Massive, condense is formed on the walls of the PVC tubes, irrespective of the season. The continuous measuring, for a period of several months, of more abiotic parameters, amongst which the temperature of the dew point was carried out with dataloggers, which were installed at different depths in limestone scree. This type of continuous monitoring of abiotic parameters at different scree depths is a premiere for Leaota and even is a first for Romania.

  8. Live performance of male broilers subjected to constant or increasing air velocities at moderate temperatures with a high dew point.

    Science.gov (United States)

    Dozier, W A; Lott, B D; Branton, S L

    2005-08-01

    This study examined the effects of varying air velocities vs. a constant air velocity with a cyclic temperature curve of 25-30-25 degrees C and a dew point of 23 degrees C on broilers from 28 to 49 d of age. Four replicate trials were conducted. In each trial, 742 male broilers were randomly allocated to 6 floor pens or 2 air velocity tunnels, with each tunnel consisting of 4 pens. Bird density, feeder, and waterer space were similar across all pens (53 birds/ pen; 0.07 m2/bird). The treatments were control (still air), constant air velocity of 120 m/min, and increasing air velocity (90 m/min from 28 to 35 d, 120 m/min from 36 to 42 d, and 180 m/min from 43 to 49 d). Birds grown in a still air environment gained less weight, consumed less feed, and converted feed less efficiently between 28 and 49 d than birds subjected to moving air (constant or increasing). Growth responses between the air velocity treatments were similar from 28 to 35 and 36 to 42 d of age. Increasing air velocity to 180 m/min improved (P < or = 0.02) the growth rate of broilers from 43 to 49 d of age over birds receiving an air velocity of 120 m/min, but the incidence of mortality was not affected. These results provide evidence that increasing air velocity from 120 to 180 m/min is beneficial to broilers weighing 2.5 kg or greater when exposed to moderate temperatures.

  9. New correlation of dew point temperature for gases with low H/sub 2/SO/sub 4/ content

    Energy Technology Data Exchange (ETDEWEB)

    Fieg, J.

    1986-04-01

    During the last years increased concern about pollution problems has encouraged the development of many methods to remove particulate and other undesirable substances from flue gases. These efforts have also brought renewed interest in aqueous sulfuric acid vapour-liquid equilibrium for predicting the flue gas dew point. This article presents the principal methods, contributing to solve the inherent problems and summarizes the available data and presents a new empirical correlation of the dew point as a function of the partial pressures of sulfuric acid and the water in the vapour.

  10. STUDY ON THE DEW POINT TEMPERATURE IN AREAS COVERED BY COLLUVIAL MESOVOID SHALLOW SUBSTRATUM (CRYSTALLINE SCHISTS SCREE IN THE LEAOTA MOUNTAINS, 2014

    Directory of Open Access Journals (Sweden)

    Magdalin Leonard Dorobăţ

    2015-12-01

    Full Text Available This paper present and discussed the results of the monitoring of the dew point values, recorded in October and November 2014, in an ecological station in the Leaota Mountains. In this station, two polls were located in areas covered by colluvial mesovoid shallow substratum (MSS formed by epi- and mesometamorphic crystalline schists. In the ecological stations we located in the Leaota Mountains, almost always we found condensation on the walls of the polls tubes placed at different depths. Most often in spring or autumn or in other cold days, the dew point is more revealing regarding the recording actual amount of moisture in the air, than the relative humidity indicator. This work is part of a larger project that seeks correlations between ecological factors (humidity, temperature and dew point registered in various types of screes (limestone and crystalline schists and some zoocenotic components (invertebrates. This research aim to know the importance of mesovoid shallow substratum for invertebrates or small vertebrates fauna and represents a premiere for Leaota Mountains, not only regarding the continuous monitoring of some ecologic factors of these types of ecosystems (MSS, rarely researched even at global level, and also regarding the inventory of the invertebrate fauna in scree for these mountains.

  11. Satellite-derived vertical profiles of temperature and dew point for mesoscale weather forecast

    Science.gov (United States)

    Masselink, Thomas; Schluessel, P.

    1995-12-01

    Weather forecast-models need spatially high resolutioned vertical profiles of temperature and dewpoint for their initialisation. These profiles can be supplied by a combination of data from the Tiros-N Operational Vertical Sounder (TOVS) and the imaging Advanced Very High Resolution Radiometer (AVHRR) on board the NOAA polar orbiting sate!- lites. In cloudy cases the profiles derived from TOVS data only are of insufficient accuracy. The stanthrd deviations from radiosonde ascents or numerical weather analyses likely exceed 2 K in temperature and 5Kin dewpoint profiles. It will be shown that additional cloud information as retrieved from AVHIRR allows a significant improvement in theaccuracy of vertical profiles. The International TOVS Processing Package (ITPP) is coupled to an algorithm package called AVHRR Processing scheme Over cLouds, Land and Ocean (APOLLO) where parameters like cloud fraction and cloud-top temperature are determined with higher accuracy than obtained from TOVS retrieval alone. Furthermore, a split-window technique is applied to the cloud-free AVHRR imagery in order to derive more accurate surface temperatures than can be obtained from the pure TOVS retrieval. First results of the impact of AVHRR cloud detection on the quality of the profiles are presented. The temperature and humidity profiles of different retrieval approaches are validated against analyses of the European Centre for Medium-Range Weatherforecasts.

  12. Increasing the efficiency of heating systems by reducing the flue gas temperature below the dew point

    Energy Technology Data Exchange (ETDEWEB)

    Kremer, H.

    1981-06-01

    This paper deals with the fundamentals and technical possibilities of increasing the combustion efficiency of gas-fired heating units for domestic heating by cooling the flue gases below their water vapor saturation temperature. The improvement of the efficiency can be more than 15% in comparison even to modern warm water heating boilers. Important however is the availability of cooling fluids of sufficiently low temperatures which could be recirculated heating water, freshwater and air. Different possible applications of this method are discussed in detail.

  13. Experimental investigation of a super performance dew point air cooler

    International Nuclear Information System (INIS)

    Xu, Peng; Ma, Xiaoli; Zhao, Xudong; Fancey, Kevin

    2017-01-01

    Highlights: •The cooler had a complex heat & mass exchanger with an advanced wet material layer. •Intermittent water supply scheme was implemented. •The cooler achieved 100–160% higher COP compared to the existing dew point coolers. •Electricity use of the cooler was reduced by 50–70% compared to existing dew coolers. •This optimal working air ratio was 0.364 that enabled maximised cooling effectiveness. -- Abstract: This paper presents an experimental investigation of a super performance dew point air cooler which, by employing a super performance wet material layer, innovative heat and mass exchanger and intermittent water supply scheme, has achieved a significantly higher energy efficiency (i.e. Coefficient of Performance, COP) and a much lower electrical energy use compared to the existing air coolers of the same type. This involves the dedicated system design & construction, fully planned experimental testing under various simulated climatic conditions representing the climate of hot & dry, warm & dry, moderate, warm & humid and standard lab testing condition, testing results analysis and discussion, as well as the parallel comparison against the commercial dew point air cooler. Under the standard test condition, i.e. dry bulb temperature of 37.8 °C and coincident wet bulb temperature of 21.1 °C, the prototype cooler achieved the wet-bulb cooling effectiveness of 114% and dew-point cooling effectiveness of 75%, yielding a significantly high COP value of 52.5 at the optimal working air ratio of 0.364. The testing also indicated that the lower inlet air relative humidity led to a higher cooling efficiency, while the lower cooling output helped increase COP and cooling effectiveness (including the wet-bulb effectiveness and dew-point effectiveness) of the cooler.

  14. Study of temperature, air dew point temperature and reactant flow effects on proton exchange membrane fuel cell performances using electrochemical spectroscopy and voltammetry techniques

    Energy Technology Data Exchange (ETDEWEB)

    Wasterlain, S.; Hissel, D. [FC LAB, Techn' Hom, rue Thierry Mieg, 90010 Belfort Cedex (France); FEMTO-ST (UMR CNRS 6174), ENISYS Department, University of Franche-Comte, Techn' Hom, rue Thierry Mieg, 90010 Belfort Cedex (France); Candusso, D.; Harel, F. [FC LAB, Techn' Hom, rue Thierry Mieg, 90010 Belfort Cedex (France); INRETS, The French National Institute for Transport and Safety Research, Techn' Hom, rue Thierry Mieg, 90010 Belfort Cedex (France); Bergman, P.; Menard, P.; Anwar, M. [University of Connecticut, Connecticut Global Fuel Cell Center Department of Electrical and Computer Engineering, 44 Weaver Road, Unit 5233, Storrs, CT 06269-5233 (United States)

    2010-02-15

    A single PEMFC has been operated by varying the assembly temperature, the air dew point temperature and the anode/cathode stoichiometry rates with the aim to identify the parameters and combinations of factors affecting the cell performance. Some of the experiments were conducted with low humidified reactants (relative humidity of 12%). The FC characterizations tests have been conducted using in situ electrochemical methods based on load current and cell voltage signal analysis, namely: polarization curves, EIS measurements, cyclic and linear sweep voltammetries (CV and LSV). The impacts of the parameters on the global FC performances were observed using the polarization curves whereas EIS, CV and LSV test results were used to discriminate the different voltage loss sources. The test results suggest that some parameter sets allow maximal output voltages but can also induce material degradation. For instance, higher FC temperature and air flow values can induce significant electrical efficiency benefits, notably by increasing the reversible potential and the reaction kinetics. However, raising the cell temperature can also gradually dry the FC and increase the risk of membrane failure. LSV has also shown that elevated FC temperature and relative humidity can also accelerate the electrolyte degradation (i.e. slightly higher fuel crossover rate) and reduce the lifetime consequently. (author)

  15. Study of temperature, air dew point temperature and reactant flow effects on proton exchange membrane fuel cell performances using electrochemical spectroscopy and voltammetry techniques

    Science.gov (United States)

    Wasterlain, S.; Candusso, D.; Hissel, D.; Harel, F.; Bergman, P.; Menard, P.; Anwar, M.

    A single PEMFC has been operated by varying the assembly temperature, the air dew point temperature and the anode/cathode stoichiometry rates with the aim to identify the parameters and combinations of factors affecting the cell performance. Some of the experiments were conducted with low humidified reactants (relative humidity of 12%). The FC characterizations tests have been conducted using in situ electrochemical methods based on load current and cell voltage signal analysis, namely: polarization curves, EIS measurements, cyclic and linear sweep voltammetries (CV and LSV). The impacts of the parameters on the global FC performances were observed using the polarization curves whereas EIS, CV and LSV test results were used to discriminate the different voltage loss sources. The test results suggest that some parameter sets allow maximal output voltages but can also induce material degradation. For instance, higher FC temperature and air flow values can induce significant electrical efficiency benefits, notably by increasing the reversible potential and the reaction kinetics. However, raising the cell temperature can also gradually dry the FC and increase the risk of membrane failure. LSV has also shown that elevated FC temperature and relative humidity can also accelerate the electrolyte degradation (i.e. slightly higher fuel crossover rate) and reduce the lifetime consequently.

  16. Intercomparison of the Dew-Point Temperature Realizations at LPM and MIKES in the Range from -70 °C to + 20 ° C

    Science.gov (United States)

    Heinonen, Martti; Zvizdic, Davor; Sestan, Danijel

    2012-09-01

    The first European humidity key comparison EURAMET-T.K6 was completed in 2008, and it covered the dew-point temperature range from -50 °C to + 20 °C. Both LPM and MIKES participated in the comparison, but a new low dew-point generator was introduced at LPM as a result of progress in the EUROMET P912 project. To extend the range of available comparison evidence down to -70 °C and to study the validity of improved uncertainties of LPM, a bilateral comparison was carried out between LPM and MIKES in 2009-2010. The applied comparison procedure was similar to that applied in EURAMET-T.K6. However, only one transfer standard was used instead of two units and the measurement point -70 °C was added in the measurement scheme. The results show that the bilateral equivalence between LPM and MIKES is between (0.00 ± 0.06) °C and (0.02 ± 0.08) °C in the range from -50 °C to + 20 °C and (0.01 ± 0.10) °C at -70 °C. Using MIKES results as the link to the EURAMET.T-K6, it is shown that the difference between the results obtained with the new LPM dew-point temperature standard and the EURAMET Comparison Reference Values is between (-0.02 ± 0.08) °C at 20 °C and (+ 0.02 ± 0.07) ° C at -50 °C.

  17. Dew Frequency across the NEON Network from Infrared Radiometry

    Science.gov (United States)

    Ritter, F.; Berkelhammer, M. B.; Beysens, D.

    2017-12-01

    The surface energy budget is more difficult to close at night because of the absence of strong atmospheric turbulence, central in the eddy-covariance calculations. One approach to assessing the direction of the nocturnal latent heat flux is through studying the frequency and magnitude of dew formation in different ecosystems. However, most former dew studies on dew dynamics utilized artificial surfaces to collect dew, and did not have access to the surface temperature of natural surfaces in an ecosystem to provide a continuous whole-plot approach to constrain dew formation. Hourly in-situ measurements recently made available by the National Ecological Observatory Network (NEON) of the radiometric surface temperature and the meteorological variables provide a unique opportunity to make continuous estimates of dew formation across 19 ecosystems (9 grasslands and 10 forests) at the plot-scale. Here, dew duration was calculated for each night based on the difference between the surface temperature and the dew point temperature of the air. The results from this analysis show that dew duration is limited by wind speed during the night, with a maximum dew yield at 1.1 m/s and no dew occurrence when the wind speed exceeds 7 m/s. This observation is consistent with previous studies but has been expanded here across multiple biomes to produce a well-defined turbulent limit on dew formation. The sensitivity of dew to wind speed arises because of the exhaustion of the water vapor supply close to the surface of the leaf at very low wind speed, and because the enhanced thermal exchange between the air and the surface counteracts dewfall at high wind speed. This well-defined wind speed limit that persists across sites and seasons could help to estimate the surface energy budget at night by constraining the latent heat flux.

  18. Bilateral key comparison SIM.T-K6.1 on humidity standards in the dew/frost-point temperature range from -25 °C to +20 °C

    Science.gov (United States)

    Meyer, C. W.; Hill, K. D.

    2015-01-01

    A Regional Metrology Organization (RMO) Key Comparison of dew/frost point temperatures was carried out by the National Institute of Standards and Technology (NIST, USA) and the National Research Council (NRC, Canada) between December 2014 and April 2015. The results of this comparison are reported here, along with descriptions of the humidity laboratory standards for NIST and NRC and the uncertainty budget for these standards. This report also describes the protocol for the comparison and presents the data acquired. The results are analyzed, determining degree of equivalence between the dew/frost-point standards of NIST and NRC. This paper is the final report of the comparison including analysis of the uncertainty of measurement results. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT WG-KC, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  19. Relationship between relative humidity and the dew point ...

    African Journals Online (AJOL)

    This research was aimed at determining the relationship between relative humidity and the dew point temperature in Benin City, Edo State, Nigeria. The dew point temperature was approximated from the measured air temperature and relative humidity with the aid of a currently self-designed weather monitoring system.

  20. Fort St. Vrain high temperature gas-cooled reactor. Pt. 12. The dew point moisture monitor testing program

    Energy Technology Data Exchange (ETDEWEB)

    Olson, H.G. (Colorado State Univ., Fort Collins (USA). Dept. of Mechanical Engineering); Brey, H.L. (Public Service Co. of Colorado, Denver (USA)); Swart, F.E. (Gas-Cooled Reactor Associates, La Jolla, CA (USA)); Forbis, J.M. (Storage Technology Corp., Louisville, CO (USA))

    1982-09-01

    Moisture ingress into the core volume could cause damaging reactions with the moderator-reflector graphite and burnable poison, therefore a dew point moisture monitoring system has been developed with the basic design criteria that a plant protective system trip is signaled after the system detects high primary coolant helium moisture levels and that the system is able to correctly identify which of two steam generator loops is leaking. Modifications to the sample supplies to the monitors were necessary to reduce the system's unsatisfactory response time at lower reactor power levels.

  1. Smart textile plasmonic fiber dew sensors.

    Science.gov (United States)

    Esmaeilzadeh, Hamid; Rivard, Maxime; Arzi, Ezatollah; Légaré, François; Hassani, Alireza

    2015-06-01

    We propose a novel Surface Plasmon Resonance (SPR)-based sensor that detects dew formation in optical fiber-based smart textiles. The proposed SPR sensor facilitates the observation of two phenomena: condensation of moisture and evaporation of water molecules in air. This sensor detects dew formation in less than 0.25 s, and determines dew point temperature with an accuracy of 4%. It can be used to monitor water layer depth changes during dew formation and evaporation in the range of a plasmon depth probe, i.e., 250 nm, with a resolution of 7 nm. Further, it facilitates estimation of the relative humidity of a medium over a dynamic range of 30% to 70% by measuring the evaporation time via the plasmon depth probe.

  2. Increase in the boiler's performance in terms of the acid dew point temperature: Environmental advantages of replacing fuels

    Energy Technology Data Exchange (ETDEWEB)

    Blanco, J.M.; Pena, F. [Dpto. Maquinas y Motores Termicos, Escuela Tecnica Superior de Ingenieria, Universidad del Pais Vasco/E.H.U., Alameda de Urquijo s/n (48013) Bilbao (Spain)

    2008-05-15

    The aim of air pre-heaters is to raise the temperature of the combustion air in boilers, using heat recovered from the power plant combustion gases. On the one hand, this paper compares the effects of the acid dew point temperature (ADT) on pre-heaters in a reference thermal power plant for two types of fuel, ''fuel No. 2'' and ''low sulphur fuel'' respectively and on the other hand, it shows how a changeover to this latter fuel would increase the useful lifetime of this equipment, reducing this way cost of maintenance due to the considerable decrease in the area exposed to ADT with the subsequent increase in the boiler's performance. (author)

  3. Multi-channel fiber optic dew and humidity sensor

    Science.gov (United States)

    Limodehi, Hamid E.; Mozafari, Morteza; Amiri, Hesam; Légaré, François

    2018-03-01

    In this article, we introduce a multi-channel fiber optic dew and humidity sensor which works using a novel method based on relation between surface plasmon resonance (SPR) and water vapor condensation. The proposed sensor can instantly detect moisture or dew formation through its fiber optic channels, separately situated in different places. It enables to simultaneously measure the ambient Relative Humidity (RH) and dew point temperature of several environments with accuracy of 5%.

  4. Acid dew point measurements in combustion gases using the dew point measuring system AH 85100

    Energy Technology Data Exchange (ETDEWEB)

    Fehler, D.

    1984-01-01

    Measuring system for continuous monitoring of the SO/sub 2//SO/sub 3/ dew point in the flue gas, characterized by a low failure rate, applicability inside the flue gas duct, maintenance-free continuous operation, and self-cleaning. The measuring principle is the cooling of the sensor element down to the 'onset condensation' message. Sensor surface temperatures are listed and evaluated as flue gas dew point temperatures. The measuring system is described. (DOMA).

  5. BILATERAL KEY COMPARISON SIM.T-K6.1 ON HUMIDITY STANDARDS IN THE DEW/FROST-POINT TEMPERATURE RANGE FROM −25 °C TO +20 °C

    Science.gov (United States)

    Meyer, C.W.; Hill, K.D.

    2015-01-01

    A Regional Metrology Organization (RMO) Key Comparison of dew/frost point temperatures was carried out by the National Institute of Standards and Technology (NIST, USA) and the National Research Council (NRC, Canada) between December 2014 and April, 2015. The results of this comparison are reported here, along with descriptions of the humidity laboratory standards for NIST and NRC and the uncertainty budget for these standards. This report also describes the protocol for the comparison and presents the data acquired. The results are analyzed, determining degree of equivalence between the dew/frost-point standards of NIST and NRC. PMID:26663952

  6. Is KCl(g) corrosive at temperatures above its dew point? Influence of KCl(g) on initial stages of the high temperature corrosion of 11% Cr steel at 600 C

    Energy Technology Data Exchange (ETDEWEB)

    Segerdahl, K.; Pettersson, J.; Svensson, J.E.; Johansson, L.G. [Dept. of Environmental Inorganic Chemistry, High Temperature Corrosion Centre, Chalmers Univ. of Technology, Goeteborg (Sweden)

    2004-07-01

    The influence of gaseous KCl on the high temperature oxidation of CrMoV11 1 (X20) steel at 600 C is reported. The sample temperature was above the dew point of KCl, the partial pressure of KCl being about 5ppm. The samples were investigated by a number of surface analytical techniques including grazing angle XRD, SEM/EDX, and SAM. CrMoV11 1 steel shows protective behaviour in clean dry O{sub 2} and O{sub 2}/H{sub 2}O environment because of the formation of a chromium-rich oxide ({alpha}-(Fe,Cr){sub 2}O{sub 3}). It is often considered that alkali salts accelerate the corrosion of steel only when present on the surface in solid or liquid form. In contrast, the present result shows that gaseous KCl is very corrosive, also in the absence of condensation. KCl(g) reacts with chromium in the scale, forming K{sub 2}CrO{sub 4}(s). This depletes the protective oxide in chromium and leads to the formation of non-protective hematite, Fe{sub 2}O{sub 3}. (orig.)

  7. Influence of the burning point on the dew point in a diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Teetz, C.

    1982-06-01

    A computation on the influence of the ignition point on the dew point in a cylinder of a diesel engine is presented. The cylinder-pressure diagrams are shown. The results of computation are given. A later ignition point diminishes the area with cylinder wall temperatures below the dew point. The endangering by cylinder wall temperatures below the dew point is illustrated.

  8. TFOS DEWS II Report Executive Summary.

    Science.gov (United States)

    Craig, Jennifer P; Nelson, J Daniel; Azar, Dimitri T; Belmonte, Carlos; Bron, Anthony J; Chauhan, Sunil K; de Paiva, Cintia S; Gomes, José A P; Hammitt, Katherine M; Jones, Lyndon; Nichols, Jason J; Nichols, Kelly K; Novack, Gary D; Stapleton, Fiona J; Willcox, Mark D P; Wolffsohn, James S; Sullivan, David A

    2017-10-01

    This article presents an Executive Summary of the conclusions and recommendations of the 10-chapter TFOS DEWS II report. The entire TFOS DEWS II report was published in the July 2017 issue of The Ocular Surface. A downloadable version of the document and additional material, including videos of diagnostic and management techniques, are available on the TFOS website: www.TearFilm.org. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Spatial interpolation of hourly precipitation and dew point temperature for the identification of precipitation phase and hydrologic response in a mountainous catchment

    Science.gov (United States)

    Garen, D. C.; Kahl, A.; Marks, D. G.; Winstral, A. H.

    2012-12-01

    In mountainous catchments, it is well known that meteorological inputs, such as precipitation, air temperature, humidity, etc. vary greatly with elevation, spatial location, and time. Understanding and monitoring catchment inputs is necessary in characterizing and predicting hydrologic response to these inputs. This is true all of the time, but it is the most dramatically critical during large storms, when the input to the stream system due to rain and snowmelt creates the potential for flooding. Besides such crisis events, however, proper estimation of catchment inputs and their spatial distribution is also needed in more prosaic but no less important water and related resource management activities. The first objective of this study is to apply a geostatistical spatial interpolation technique (elevationally detrended kriging) to precipitation and dew point temperature on an hourly basis and explore its characteristics, accuracy, and other issues. The second objective is to use these spatial fields to determine precipitation phase (rain or snow) during a large, dynamic winter storm. The catchment studied is the data-rich Reynolds Creek Experimental Watershed near Boise, Idaho. As part of this analysis, precipitation-elevation lapse rates are examined for spatial and temporal consistency. A clear dependence of lapse rate on precipitation amount exists. Certain stations, however, are outliers from these relationships, showing that significant local effects can be present and raising the question of whether such stations should be used for spatial interpolation. Experiments with selecting subsets of stations demonstrate the importance of elevation range and spatial placement on the interpolated fields. Hourly spatial fields of precipitation and dew point temperature are used to distinguish precipitation phase during a large rain-on-snow storm in December 2005. This application demonstrates the feasibility of producing hourly spatial fields and the importance of doing

  10. Phase-equilibria for design of coal-gasification processes: dew points of hot gases containing condensible tars. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Prausnitz, J.M.

    1980-05-01

    This research is concerned with the fundamental physical chemistry and thermodynamics of condensation of tars (dew points) from the vapor phase at advanced temperatures and pressures. Fundamental quantitative understanding of dew points is important for rational design of heat exchangers to recover sensible heat from hot, tar-containing gases that are produced in coal gasification. This report includes essentially six contributions toward establishing the desired understanding: (1) Characterization of Coal Tars for Dew-Point Calculations; (2) Fugacity Coefficients for Dew-Point Calculations in Coal-Gasification Process Design; (3) Vapor Pressures of High-Molecular-Weight Hydrocarbons; (4) Estimation of Vapor Pressures of High-Boiling Fractions in Liquefied Fossil Fuels Containing Heteroatoms Nitrogen or Sulfur; and (5) Vapor Pressures of Heavy Liquid Hydrocarbons by a Group-Contribution Method.

  11. sarcome d'ewing

    African Journals Online (AJOL)

    7 mai 2012 ... Le sarcome d'Ewing est une tumeur osseuse rare corres- pondant à la ... Introduction : petrous Ewing sarcoma is exceptional. We report a ..... (15) Iriz A, Albayrak L, Eryilmaz A. Extraskeletal primary Ewing's sarcoma of the.

  12. Dew measurement and estimation of rain-fed jujube (Zizyphus jujube Mill) in a semi-arid loess hilly region of China

    Institute of Scientific and Technical Information of China (English)

    WANG Xing; GAO Zhiyong; WANG Youke; Wang Zhi; JIN Shanshan

    2017-01-01

    Dew is an important water source for plants in arid and semi-arid regions.However,information on dew is scarce in such regions.In this study,we explored dew formation,amount,and duration of rain-fed jujube (Zi(w)phus jujube Mill) trees in a semi-arid loess hilly region of China (i.e.,Mizhi County).The data included dew intensity and duration,relative humidity,temperature,and wind speed measured from 26 July to 23 October,2012 and from 24 June to 17 October,2013 using a micro-climate system (including dielectric leaf wetness sensors,VP-3 Relative Humidity/Temperature Sensor,High Resolution Rain Gauge,and Davis Cup Anemometer).The results show that atmospheric conditions of relative humidity of >78% and dew point temperature of 1℃C-3℃C are significantly favorable to dew formation.Compared with the rainfall,dew was characterized by high frequency,strong stability,and long duration.Furthermore,heavy dew accounted for a large proportion of the total amount.The empirical models (i.e.,relative humidity model (RH model) and dew point depression model (DPD model)) for daily dew duration estimation performed well at 15-rain intervals,with low errors ranging between 1.29 and 1.60 h,respectively.But it should be noted that the models should be calibrated firstly by determining the optimal thresholds of relatively humidity for RH model and dew point depression for DPD model.For rain-fed jujube trees in the semi-arid loess hilly regions of China,the optimal threshold of relative humidity was 78%,and the optimal upper and lower thresholds of dew point depression were 1℃C and 5℃C,respectively.The study further demonstrates that dew is an important water resource that cannot be ignored for rain-fed jujube trees and may affect water balance at regional scales.

  13. Projected climate change impacts upon dew yield in the Mediterranean basin

    Energy Technology Data Exchange (ETDEWEB)

    Tomaszkiewicz, M. [Department of Civil & Environmental Engineering, Faculty of Engineering & Architecture, American University of Beirut, Beirut (Lebanon); Abou Najm, M., E-mail: majdian@aub.edu.lb [Department of Civil & Environmental Engineering, Faculty of Engineering & Architecture, American University of Beirut, Beirut (Lebanon); Beysens, D. [Physique et Mecanique des Milieux Heterogenes, UMR 7636 CNRS — ESPCI, Universite Pierre et Marie Curie — Universite Paris Diderot, 10 rue Vauquelin, 75005 Paris (France); Service des Basses Temperatures, CEA-Grenoble & Universite Joseph Fourier, Grenoble (France); OPUR, 60 rue Emeriau, 75015 Paris (France); Alameddine, I. [Department of Civil & Environmental Engineering, Faculty of Engineering & Architecture, American University of Beirut, Beirut (Lebanon); Bou Zeid, E. [Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08540 (United States); El-Fadel, M. [Department of Civil & Environmental Engineering, Faculty of Engineering & Architecture, American University of Beirut, Beirut (Lebanon)

    2016-10-01

    Water scarcity is increasingly raising the need for non-conventional water resources, particularly in arid and semi-arid regions. In this context, atmospheric moisture can potentially be harvested in the form of dew, which is commonly disregarded from the water budget, although its impact may be significant when compared to rainfall during the dry season. In this study, a dew atlas for the Mediterranean region is presented illustrating dew yields using the yield data collected for the 2013 dry season. The results indicate that cumulative monthly dew yield in the region can exceed 2.8 mm at the end of the dry season and 1.5 mm during the driest months, compared to < 1 mm of rainfall during the same period in some areas. Dew yields were compared with potential evapotranspiration (PET) and actual evapotranspiration (ET) during summer months thus highlighting the role of dew to many native plants in the region. Furthermore, forecasted trends in temperature and relative humidity were used to estimate dew yields under future climatic scenarios. The results showed a 27% decline in dew yield during the critical summer months at the end of the century (2080). - Highlights: • Dew atlas for Mediterranean region is presented. • Cumulative dew yields can exceed 2.8 mm at the end of the dry season. • Dew yields compared with PET and ET show the role of dew to many native plants. • Forecasted trends under future climatic scenarios show a 27% decline in dew yield.

  14. Characterization of Emericella nidulans RodA and DewA hydrophobin mutants

    DEFF Research Database (Denmark)

    Jensen, Britt Guillaume; Nielsen, Jakob Blæsbjerg; Pedersen, Mona Højgaard

    hydrophobins RodA and DewA. Individual knock-out mutants rodAΔ, dewAΔ and the double deletion strain rodAΔdewAΔ were constructed. Furthermore, two strains containing a point mutation in the first of the cysteines of RodA (rodA-C57G), where one was coupled to the dewA deletion, were included. The reference...... strain (NID1) and dewAΔ displayed green conidia. However, rodAΔ and rodAΔdewAΔ showed a dark green/brown conidial pigmentation, while rodA-C57G and rodAC57G dewAΔ displayed lighter brown conidia. rodAΔ and rodAΔdewAΔ displayed a higher degree of hülle cells compared to the moderate amount observed...... for NID1 and dewAΔ, while rodA-C57G and rodA-C57G dewAΔ displayed a low number of hülle cells. NID1 and dewAΔ conidia were dispersed as spore chains. rodAΔ, rodAΔdewAΔ, rodA-C57G and rodA-C57G dewAΔ spores were associated in large clumps, where the conidia seemed to adhere to one another. The largest...

  15. Impact of Continuous Cropping on the Diurnal Range of Dew Point Temperature during the Foliar Expansion Period of Annual Crops on the Canadian Prairies

    Directory of Open Access Journals (Sweden)

    Bharat M. Shrestha

    2016-01-01

    Full Text Available It is important to increase our knowledge of the role of land use in changing the regional climate. This study asked, “Has the increase in continuous cropping over the past 50 years on the Canadian Prairies influenced the daily mean and range of morning dew point temperatures (Td during the foliar expansion period (from mid-June to mid-July of annual field crops?” We found that there has been a general increase in the decadal average of mean daily Td and in the range of morning Td from the 1960s to the 2000s. The increase in the observed range of Td between the daily minimum value, which typically occurs near sunrise, and the late morning peak was found to be related to the increase in annual crop acreage and consequent decrease in summerfallow area. The relationship was more significant in the subhumid climatic zone than in the semiarid climatic zone, and it was influenced by whether the region was experiencing either wet, normal, or dry conditions.

  16. BILATERAL KEY COMPARISON SIM.T-K6.5 ON HUMIDITY STANDARDS IN THE DEW/FROST-POINT TEMPERATURE RANGE FROM -30 °C TO +20 °C.

    Science.gov (United States)

    Meyer, C W; Solano, A

    2016-01-01

    A Regional Metrology Organization (RMO) Key Comparison of dew/frost point temperatures over the range -30 °C TO +20 °C was carried out by the National Institute of Standards and Technology (NIST, USA) and the Laboratorio Costarricense de Metrología (LACOMET, Costa Rica), between February 2015 and August 2015. The results of this comparison are reported here, along with descriptions of the humidity laboratory standards for NIST and LACOMET and the uncertainty budget for these standards. This report also describes the protocol for the comparison and presents the data acquired. The results are analyzed, determining the degree of equivalence between the dew/frost-point standards of NIST and LACOMET.

  17. BILATERAL KEY COMPARISON SIM.T-K6.5 ON HUMIDITY STANDARDS IN THE DEW/FROST-POINT TEMPERATURE RANGE FROM −30 °C TO +20 °C

    Science.gov (United States)

    Meyer, C.W.; Solano, A.

    2016-01-01

    A Regional Metrology Organization (RMO) Key Comparison of dew/frost point temperatures over the range −30 °C TO +20 °C was carried out by the National Institute of Standards and Technology (NIST, USA) and the Laboratorio Costarricense de Metrología (LACOMET, Costa Rica), between February 2015 and August 2015. The results of this comparison are reported here, along with descriptions of the humidity laboratory standards for NIST and LACOMET and the uncertainty budget for these standards. This report also describes the protocol for the comparison and presents the data acquired. The results are analyzed, determining the degree of equivalence between the dew/frost-point standards of NIST and LACOMET. PMID:28066029

  18. Bilateral key comparison SIM.T-K6.2 on humidity standards in the dew/frost-point temperature range from -20 °c to 20 °c

    Science.gov (United States)

    Huang, P. H.; Meyer, C. W.; Martines-López, E.; Dávila Pacheco, J. A.; Méndez-Lango, E.

    2014-01-01

    A Regional Metrology Organization (RMO) Key Comparison of dew/frost point temperatures was carried out by the National Institute of Standards and Technology (NIST, USA) and the Centro Nacional de Metrologia (CENAM, Mexico) between July 2008 and December 2008. The results of this comparison are reported here, along with descriptions of the humidity laboratory standards for NIST and CENAM and the uncertainty budget for these standards. This report also describes the protocol for the comparison and presents the data acquired. The results are analyzed, determining degree of equivalence between the dew/frost-point standards of NIST and CENAM. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  19. Tar dew point analyser as a tool in biomass gasification

    Energy Technology Data Exchange (ETDEWEB)

    Vreugdenhil, B.J.; Kuipers, J. [ECN Biomass, Coal and Environmental Research, Petten (Netherlands)

    2008-08-15

    Application of the Tar Dew point Analyzer (TDA) in different biomass based gasification systems and subsequent gas cleaning setups has been proven feasible. Such systems include BFB gasifiers, CFB gasifier and fixed bed gasifiers, with tar crackers or different scrubbers for tar removal. Tar dew points obtained with the TDA give direct insight in the performance of the gas cleaning section and help prevent any tar related problems due to condensation. The current TDA is capable of measuring tar dew points between -20 to 200C. This manuscript will present results from 4 different gasification setups. The range of measured tar dew points is -7 to 164C with comparable results from the calculated dew points based on the SPA measurements. Further detail will be presented on the differences between TDA and SPA results and explanations will be given for deviations that occurred. Improvements for the TDA regarding future work will be presented.

  20. Enhanced battery model including temperature effects

    NARCIS (Netherlands)

    Rosca, B.; Wilkins, S.

    2013-01-01

    Within electric and hybrid vehicles, batteries are used to provide/buffer the energy required for driving. However, battery performance varies throughout the temperature range specific to automotive applications, and as such, models that describe this behaviour are required. This paper presents a

  1. Continuous acid dew point measurement in coal-fired power plants; Kontinuierliche Saeuretaupunktmessung in Braunkohlekraftwerken

    Energy Technology Data Exchange (ETDEWEB)

    Foedisch, Holger; Schulz, Joerg; Schengber, Petra; Dietrich, Gabriele [Dr. Foedisch Umweltmesstechnik AG, Markranstaedt (Germany)

    2009-07-01

    The reduction of flue gas losses is one option to increase power plant efficiency. The target is the optimised low waste gas temperature. When applying lignite and other high-sulphur fuels the temperature of the flue gas is mainly determined by the acid dew point. Temperature of the flue gas system is to amount some 10 to 20 K above the assumed acid dew point. The acid dew point measuring system AMD 08 is able to detect the real acid dew point in a quasi-continuous way. Thus, it is possible to deliberately decrease waste gas temperature. (orig.)

  2. Final report on CCT-K6: Comparison of local realisations of dew-point temperature scales in the range -50 °C to +20 °C

    Science.gov (United States)

    Bell, S.; Stevens, M.; Abe, H.; Benyon, R.; Bosma, R.; Fernicola, V.; Heinonen, M.; Huang, P.; Kitano, H.; Li, Z.; Nielsen, J.; Ochi, N.; Podmurnaya, O. A.; Scace, G.; Smorgon, D.; Vicente, T.; Vinge, A. F.; Wang, L.; Yi, H.

    2015-01-01

    A key comparison in dew-point temperature was carried out among the national standards held by NPL (pilot), NMIJ, INTA, VSL, INRIM, MIKES, NIST, NIM, VNIIFTRI-ESB and NMC. A pair of condensation-principle dew-point hygrometers was circulated and used to compare the local realisations of dew point for participant humidity generators in the range -50 °C to +20 °C. The duration of the comparison was prolonged by numerous problems with the hygrometers, requiring some repairs, and several additional check measurements by the pilot. Despite the problems and the extended timescale, the comparison was effective in providing evidence of equivalence. Agreement with the key comparison reference value was achieved in the majority of cases, and bilateral degrees of equivalence are also reported. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  3. A micro dew point sensor with a thermal detection principle

    Science.gov (United States)

    Kunze, M.; Merz, J.; Hummel, W.-J.; Glosch, H.; Messner, S.; Zengerle, R.

    2012-01-01

    We present a dew point temperature sensor with the thermal detection of condensed water on a thin membrane, fabricated by silicon micromachining. The membrane (600 × 600 × ~1 µm3) is part of a silicon chip and contains a heating element as well as a thermopile for temperature measurement. By dynamically heating the membrane and simultaneously analyzing the transient increase of its temperature it is detected whether condensed water is on the membrane or not. To cool the membrane down, a peltier cooler is used and electronically controlled in a way that the temperature of the membrane is constantly held at a value where condensation of water begins. This temperature is measured and output as dew point temperature. The sensor system works in a wide range of dew point temperatures between 1 K and down to 44 K below air temperature. In experimental investigations it could be proven that the deviation of the measured dew point temperatures compared to reference values is below ±0.2 K in an air temperature range of 22 to 70 °C. At low dew point temperatures of -20 °C (air temperature = 22 °C) the deviation increases to nearly -1 K.

  4. A micro dew point sensor with a thermal detection principle

    International Nuclear Information System (INIS)

    Kunze, M; Merz, J; Glosch, H; Messner, S; Zengerle, R; Hummel, W-J

    2012-01-01

    We present a dew point temperature sensor with the thermal detection of condensed water on a thin membrane, fabricated by silicon micromachining. The membrane (600 × 600 × ∼1 µm 3 ) is part of a silicon chip and contains a heating element as well as a thermopile for temperature measurement. By dynamically heating the membrane and simultaneously analyzing the transient increase of its temperature it is detected whether condensed water is on the membrane or not. To cool the membrane down, a peltier cooler is used and electronically controlled in a way that the temperature of the membrane is constantly held at a value where condensation of water begins. This temperature is measured and output as dew point temperature. The sensor system works in a wide range of dew point temperatures between 1 K and down to 44 K below air temperature. In experimental investigations it could be proven that the deviation of the measured dew point temperatures compared to reference values is below ±0.2 K in an air temperature range of 22 to 70 °C. At low dew point temperatures of −20 °C (air temperature = 22 °C) the deviation increases to nearly −1 K

  5. Dew-point measurements at high water vapour pressure

    Science.gov (United States)

    Lomperski, S.; Dreier, J.

    1996-05-01

    A dew-point meter capable of measuring humidity at high vapour pressure and high temperature has been constructed and tested. Humidity measurements in pure steam were made over the temperature range 100 - 1500957-0233/7/5/003/img1C and a vapour pressure range of 1 - 4 bar. The dew-point meter performance was assessed by comparing measurements with a pressure transmitter and agreement between the two was within 0957-0233/7/5/003/img2% relative humidity. Humidity measurements in steam - air mixtures were also made and the dew-point meter readings were compared to those of a zirconia oxygen sensor. For these tests the dew-point meter readings were generally within 0957-0233/7/5/003/img2% relative humidity of the oxygen sensor measurements.

  6. Dew Point modelling using GEP based multi objective optimization

    OpenAIRE

    Shroff, Siddharth; Dabhi, Vipul

    2013-01-01

    Different techniques are used to model the relationship between temperatures, dew point and relative humidity. Gene expression programming is capable of modelling complex realities with great accuracy, allowing at the same time, the extraction of knowledge from the evolved models compared to other learning algorithms. We aim to use Gene Expression Programming for modelling of dew point. Generally, accuracy of the model is the only objective used by selection mechanism of GEP. This will evolve...

  7. Measurements to determine the sulfuric acid dew point and the SO sub 3 concentration in flue gas of power plant vessels. Messungen zur Bestimmung des Saeuretaupunktes und der SO sub 3 -Konzentration im Rauchgas von Kraftwerkskesseln

    Energy Technology Data Exchange (ETDEWEB)

    Derichs, W.; Menden, W. (RWE Energie AG, Bergheim (Germany)); Ebel, P.K. (Apparatebau Hundsbach GmbH, Baden-Baden (Germany))

    1990-01-01

    Among the customary methods of dew point determination, the technique of recording the increase in conductivity between two electrodes at the moment of acid condensing onto them, and measuring at the same time the temperature of the sensor, is appropriate to determine the sulfuric acid dew point in dust-laden flue gas. By means of the sensitivity of a newly developed sensor, the accuracy of the measurement method could be improved to such an extent that also low acid dew points and rapid changes can be recorded reliably. Measurements have shown that the acid dew point primarily depends on the SO{sub 3} content which is substantially determined by the sulfur content of the fuel and the type of flue gas ducts. Further influential quantities include flue gas humidity, air surplus, other gaseous flue gas components such as HCl and HF, as well as the quantity, composition and temperature-dependent adsorption capability of the flue dusts. (orig./BBR).

  8. A quartz crystal microbalance dew point sensor without frequency measurement

    Science.gov (United States)

    Wang, Guohua; Zhang, Weishuo; Wang, Shuo; Sun, Jinglin

    2014-11-01

    This work deals with the design of a dew point sensor based on Quartz Crystal Microbalance (QCM) without measuring the frequency. This idea is inspired by the fact that the Colpitts oscillation circuit will stop oscillating when the QCM works in the liquid media. The quartz crystal and the electrode are designed through the finite element simulation and the stop oscillating experiment is conducted to verify the sensibility. Moreover, the measurement result is calibrated to approach the true value. At last a series of dew points at the same temperature is measured with the designed sensor. Results show that the designed dew point sensor is able to detect the dew point with the proper accuracy.

  9. Acid dew point measurement in flue gases

    Energy Technology Data Exchange (ETDEWEB)

    Struschka, M.; Baumbach, G.

    1986-06-01

    The operation of modern boiler plants requires the continuous measurement of the acid dew point in flue gases. An existing measuring instrument was modified in such a way that it can determine acid dew points reliably, reproduceably and continuously. The authors present the mechanisms of the dew point formation, the dew point measuring principle, the modification and the operational results.

  10. Dew variability in three habitats of a sand dune transect in a desert oasis ecotone, Northwestern China

    CERN Document Server

    Zhuang, Yanli

    2014-01-01

    Dew, as a supplementary water source, may have an important ecological role in arid and semi-arid regions. During August and September of 2007 and 2008, measurements were taken to investigate the dew accumulation and evaporation patterns in the very early morning hours, in three different habitats (dunetop, footslope, and interdune lowland) of a fixed sand dune in Northwest China. Dew quantities were measured using the cloth-plate method. The results indicated that there was a positive correlation between dew amounts and relative humidity, but a negative correlation between dew amounts and mean temperature. Clear mornings were characterized by higher dew amounts and longer dew duration, whereas less dew was recorded during cloudy and especially windy mornings. Dew continued to condense even after sunrise, although a shorter warming time after dawn is also of vital importance in dew formation. The higher average maximum dew quantities (0.06mm) and longer average dew duration (2.3h) occurred in the interdune lo...

  11. A microwave resonance dew-point hygrometer

    Science.gov (United States)

    Underwood, R. J.; Cuccaro, R.; Bell, S.; Gavioso, R. M.; Madonna Ripa, D.; Stevens, M.; de Podesta, M.

    2012-08-01

    We report the first measurements of a quasi-spherical microwave resonator used as a dew-point hygrometer. In conventional dew-point hygrometers, the condensation of water from humid gas flowing over a mirror is detected optically, and the mirror surface is then temperature-controlled to yield a stable condensed layer. In our experiments we flowed moist air from a humidity generator through a quasi-spherical resonator and detected the onset of condensation by measuring the frequency ratio of selected microwave modes. We verified the basic operation of the device over the dew-point range 9.5-13.5 °C by comparison with calibrated chilled-mirror hygrometers. These tests indicate that the microwave method may allow a quantitative estimation of the volume and thickness of the water layer which is condensed on the inner surface of the resonator. The experiments reported here are preliminary due to the limited time available for the work, but show the potential of the method for detecting not only water but a variety of other liquid or solid condensates. The robust all-metal construction should make the device appropriate for use in industrial applications over a wide range of temperatures and pressures.

  12. A microwave resonance dew-point hygrometer

    International Nuclear Information System (INIS)

    Underwood, R J; Bell, S; Stevens, M; De Podesta, M; Cuccaro, R; Gavioso, R M; Ripa, D Madonna

    2012-01-01

    We report the first measurements of a quasi-spherical microwave resonator used as a dew-point hygrometer. In conventional dew-point hygrometers, the condensation of water from humid gas flowing over a mirror is detected optically, and the mirror surface is then temperature-controlled to yield a stable condensed layer. In our experiments we flowed moist air from a humidity generator through a quasi-spherical resonator and detected the onset of condensation by measuring the frequency ratio of selected microwave modes. We verified the basic operation of the device over the dew-point range 9.5–13.5 °C by comparison with calibrated chilled-mirror hygrometers. These tests indicate that the microwave method may allow a quantitative estimation of the volume and thickness of the water layer which is condensed on the inner surface of the resonator. The experiments reported here are preliminary due to the limited time available for the work, but show the potential of the method for detecting not only water but a variety of other liquid or solid condensates. The robust all-metal construction should make the device appropriate for use in industrial applications over a wide range of temperatures and pressures. (paper)

  13. Method and apparatus for continuously detecting and monitoring the hydrocarbon dew-point of gas

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, G.J.; Pritchard, F.R.

    1987-08-04

    This patent describes a method and apparatus for continuously detecting and monitoring the hydrocarbon dew-point of a gas. A gas sample is supplied to a dew-point detector and the temperature of a portion of the sample gas stream to be investigated is lowered progressively prior to detection until the dew-point is reached. The presence of condensate within the flowing gas is detected and subsequently the supply gas sample is heated to above the dew-point. The procedure of cooling and heating the gas stream continuously in a cyclical manner is repeated.

  14. Water harvest via dewing.

    Science.gov (United States)

    Lee, Anna; Moon, Myoung-Woon; Lim, Hyuneui; Kim, Wan-Doo; Kim, Ho-Young

    2012-07-10

    Harvesting water from humid air via dewing can provide a viable solution to a water shortage problem where liquid-phase water is not available. Here we experimentally quantify the effects of wettability and geometry of the condensation substrate on the water harvest efficiency. Uniformly hydrophilic surfaces are found to exhibit higher rates of water condensation and collection than surfaces with lower wettability. This is in contrast to a fog basking method where the most efficient surface consists of hydrophilic islands surrounded by hydrophobic background. A thin drainage path in the lower portion of the condensation substrate is revealed to greatly enhance the water collection efficiency. The optimal surface conditions found in this work can be used to design a practical device that harvests water as its biological counterpart, a green tree frog, Litoria caerulea , does during the dry season in tropical northern Australia.

  15. Winter Dew Harvest in Mexico City

    Directory of Open Access Journals (Sweden)

    Arias-Torres Jorge Ernesto

    2015-12-01

    Full Text Available This study presents experimental and theoretical results of winter dew harvest in México City in terms of condensation rate. A simplified theoretical model based on a steady-state energy balance on a radiator-condenser was fitted, as a function of the ambient temperature, the relative humidity and the wind velocity. A glass sheet and aluminum sheet white-painted were used as samples over the outdoor experiments. A good correlation was obtained between the theoretical and experimental data. The experimental results show that there was condensation in 68% of the winter nights on both condensers. The total winter condensed mass was 2977 g/m2 and 2888 g/m2 on the glass sheet and aluminum sheet white-painted, respectively. Thus, the condensed mass on the glass was only 3% higher than that on the painted surface. The maximum nightly dew harvests occurred during December, which linearly reduced from 50 g/m2 night to 22 g/m2 night as the winter months went by. The condensation occurred from 1:00 a.m. to 9:00 a.m., with maximum condensation rates between 6:00 a.m. and 7:00 a.m. The dew harvest can provide a partial alternative to the winter water shortage in certain locations with similar climates to the winter in Mexico City, as long as pollution is not significant.

  16. Final report: Bilateral key comparison SIM.T-K6.3 on humidity standards in the dew/frost-point temperature range from -30°C to 20°C

    Science.gov (United States)

    Huang, Peter; Meyer, Christopher; Brionizio, Julio D.

    2015-01-01

    A Regional Metrology Organization (RMO) Key Comparison of dew/frost point temperatures was carried out by the National Institute of Standards and Technology (NIST, USA) and the Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO, Brazil) between October 2009 and March 2010. The results of this comparison are reported here, along with descriptions of the humidity laboratory standards for NIST and INMETRO and the uncertainty budget for these standards. This report also describes the protocol for the comparison and presents the data acquired. The results are analyzed, determining degree of equivalence between the dew/frost-point standards of NIST and INMETRO. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  17. Bilateral key comparison SIM.T-K6.5 on humidity standards in the dew/frost-point temperature range from -30 °C to +20 °C

    Science.gov (United States)

    Meyer, C.; Solano, A.

    2016-01-01

    A Regional Metrology Organization (RMO) Key Comparison of dew/frost point temperatures was carried out by the National Institute of Standards and Technology (NIST, USA) and the Laboratorio Costarricense de Metrología (LACOMET, Costa Rica) between February 2015 and August 2015. The results of this comparison are reported here, along with descriptions of the humidity laboratory standards for NIST and LACOMET and the uncertainty budget for these standards. This report also describes the protocol for the comparison and presents the data acquired. The results are analyzed, determining degree of equivalence between the dew/frost-point standards of NIST and LACOMET. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  18. Study and realization of a new humid air generator; towards the definition of a dew temperature reference; Etude et realisation d'un nouveau generateur d'air humide; vers la definition d'une reference en temperature de rosee

    Energy Technology Data Exchange (ETDEWEB)

    Blanquart, B.

    2001-03-01

    The air humidity is an important parameter for several biological and physico-chemical processes. The aim of this thesis is the direct determination of the dew temperature without any link with the gravimetric reference. This document presents the realization and adjusting of a new humid air generator for the -80 deg. C to +15 deg. C range and the uncertainty linked with the dew temperature of the humid air generated. The first chapter recalls the definitions of humid air related data and the principles of the apparatuses used for the measurement of air humidity. The second chapter deals with temperature measurements while chapter 3 describes the new humid air generator built around an 'ideal' cell based on the theoretical definition of the dew temperature. Technical constraints due to temperature measurement and to hygrometers calibration are progressively integrated and introduced and lead to the practical realization of the device. Differences between the ideal cell and the prototype are estimated using a theoretical approach of mass and heat exchanges coupled with experimental results obtained with a previous prototype. Chapter 4 presents a first status of the device uncertainties with some possibilities of reduction of these uncertainties. (J.S.)

  19. Experimental study of influence characteristics of flue gas fly ash on acid dew point

    Science.gov (United States)

    Song, Jinhui; Li, Jiahu; Wang, Shuai; Yuan, Hui; Ren, Zhongqiang

    2017-12-01

    The long-term operation experience of a large number of utility boilers shows that the measured value of acid dew point is generally lower than estimated value. This is because the influence of CaO and MgO on acid dew point in flue gas fly ash is not considered in the estimation formula of acid dew point. On the basis of previous studies, the experimental device for acid dew point measurement was designed and constructed, and the acid dew point under different smoke conditions was measured. The results show that the CaO and MgO in the flue gas fly ash have an obvious influence on the acid dew point, and the content of the fly ash is negatively correlated with the temperature of acid dew point At the same time, the concentration of H2SO4 in flue gas is different, and the acid dew point of flue gas is different, and positively correlated with the acid dew point.

  20. Remotely-sensed, nocturnal, dew point correlates with malaria transmission in Southern Province, Zambia: a time-series study.

    Science.gov (United States)

    Nygren, David; Stoyanov, Cristina; Lewold, Clemens; Månsson, Fredrik; Miller, John; Kamanga, Aniset; Shiff, Clive J

    2014-06-13

    Plasmodium falciparum transmission has decreased significantly in Zambia in the last decade. The malaria transmission is influenced by environmental variables. Incorporation of environmental variables in models of malaria transmission likely improves model fit and predicts probable trends in malaria disease. This work is based on the hypothesis that remotely-sensed environmental factors, including nocturnal dew point, are associated with malaria transmission and sustain foci of transmission during the low transmission season in the Southern Province of Zambia. Thirty-eight rural health centres in Southern Province, Zambia were divided into three zones based on transmission patterns. Correlations between weekly malaria cases and remotely-sensed nocturnal dew point, nocturnal land surface temperature as well as vegetation indices and rainfall were evaluated in time-series analyses from 2012 week 19 to 2013 week 36. Zonal as well as clinic-based, multivariate, autoregressive, integrated, moving average (ARIMAX) models implementing environmental variables were developed to model transmission in 2011 week 19 to 2012 week 18 and forecast transmission in 2013 week 37 to week 41. During the dry, low transmission season significantly higher vegetation indices, nocturnal land surface temperature and nocturnal dew point were associated with the areas of higher transmission. Environmental variables improved ARIMAX models. Dew point and normalized differentiated vegetation index were significant predictors and improved all zonal transmission models. In the high-transmission zone, this was also seen for land surface temperature. Clinic models were improved by adding dew point and land surface temperature as well as normalized differentiated vegetation index. The mean average error of prediction for ARIMAX models ranged from 0.7 to 33.5%. Forecasts of malaria incidence were valid for three out of five rural health centres; however, with poor results at the zonal level. In this

  1. A New Primary Dew-Point Generator at TUBITAK UME

    Science.gov (United States)

    Oğuz Aytekin, S.; Karaböce, N.; Heinonen, M.; Sairanen, H.

    2018-05-01

    An implementation of a new low-range primary humidity generator as a part of an international collaboration between TUBITAK UME and VTT MIKES was initiated as a EURAMET Project Number 1259. The dew-point generator was designed and constructed within the scope of the cooperation between TUBITAK UME and VTT MIKES in order to extend the dew-point temperature measurement capability of Humidity Laboratory of TUBITAK UME down to - 80 °C. The system was thoroughly characterized and validated at TUBITAK UME to support the evidence for dew-point temperature uncertainties. The new generator has a capability of operating in the range of - 80 °C to +10 °C, but at the moment, it was characterized down to - 60 °C. The core of the generator system is a saturator which is fully immersed in a liquid bath. Dry air is supplied to the saturator through a temperature-controlled pre-saturator. The operation of the system is based on the single-pressure generation method with a single pass, i.e., the dew-point temperature is only controlled by the saturator temperature, and the humidity-controlled air is not returned to the system after leaving of the saturator. The metrological performance of the saturator was investigated thoroughly at both National Metrology Institutes. The pre-saturator was also tested using a thermostatic bath at VTT MIKES prior to sending them to TUBITAK UME. This paper describes the principle and design of the generator in detail. The dew-point measurement system and the corresponding uncertainty analysis of the dew-point temperature scale realized with the generator in the range from - 60 °C to 10 °C is also presented.

  2. A new comparison method for dew-point generators

    Science.gov (United States)

    Heinonen, Martti

    1999-12-01

    A new method for comparing dew-point generators was developed at the Centre for Metrology and Accreditation. In this method, the generators participating in a comparison are compared with a transportable saturator unit using a dew-point comparator. The method was tested by constructing a test apparatus and by comparing it with the MIKES primary dew-point generator several times in the dew-point temperature range from -40 to +75 °C. The expanded uncertainty (k = 2) of the apparatus was estimated to be between 0.05 and 0.07 °C and the difference between the comparator system and the generator is well within these limits. In particular, all of the results obtained in the range below 0 °C are within ±0.03 °C. It is concluded that a new type of a transfer standard with characteristics most suitable for dew-point comparisons can be developed on the basis of the principles presented in this paper.

  3. Automatic continuous dew point measurement in combustion gases

    Energy Technology Data Exchange (ETDEWEB)

    Fehler, D.

    1986-08-01

    Low exhaust temperatures serve to minimize energy consumption in combustion systems. This requires accurate, continuous measurement of exhaust condensation. An automatic dew point meter for continuous operation is described. The principle of measurement, the design of the measuring system, and practical aspects of operation are discussed.

  4. Feasibility study of a novel dew point air conditioning system for China building application

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Xudong; Yang, Shuang; Duan, Zhiyin; Riffat, Saffa B. [School of the Built Environment, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)

    2009-09-15

    The paper investigated the feasibility of a novel dew point evaporative cooling for air conditioning of buildings in China regions. The issues involved include analyses of China weather conditions, investigation of availability of water for dew point cooling, and assessment of cooling capacity of the system within various regions of China. It is concluded that the dew point system is suitable for most regions of China, particularly northern and west regions of China where the climate is hot and dry during the summer season. It is less suitable for Guangzhou and Shanghai where climates are hot and humid. However, an air pre-treatment process involving a silica-gel dehumidification will enable the technology to be used for these humid areas. Lower humidity results in a higher difference between the dry bulb and dew point of the air, which benefits the system in terms of enhancing its cooling performance. Tap water has adequate temperature to feed the system for cooling and its consumption rate is in the range 2.6-3 litres per kWh cooling output. The cooling output of the system ranges from 1.1 to 4.3 W per m{sup 3}/h air flow rate in China, depending on the region where the system applies. For a unit with 2 kW of cooling output, the required air volume flow rate varies with its application location and is in the range 570-1800 m{sup 3}/h. For a 50 m{sup 2} building with 60 W/m{sup 2} cooling load, if the system operates at working hours, i.e., 09:00 to 17:00 h, its daily water consumption would be in the range of 60-70 litres. Compared with mild or humid climates, the dry and hot climates need less air volume flow rate and less water. (author)

  5. Improvement of lithium chloride dew-point hygrometer for direct reading and controlling of relative humidity

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, X.Z.; Chu, Y.

    1986-01-01

    The lithium chloride dew-point hygrometer has many advantages over other types of hygrometers. However, it only reads and controls the dew-point temperature of air instead of the relative humidity, which is more important in industry, agriculture, food storage, and hygiene. This paper describes a new hygrometer which is based on the same principle as the lithium chloride dew-point hygrometer, but it can read and control the relative humidity directly. The instrument is quick in response and the ranges of temperature and relative humidity are quite large. Its accuracy is normally within 3% RH and its precision is within 2% RH.

  6. TFOS DEWS II pathophysiology report.

    Science.gov (United States)

    Bron, Anthony J; de Paiva, Cintia S; Chauhan, Sunil K; Bonini, Stefano; Gabison, Eric E; Jain, Sandeep; Knop, Erich; Markoulli, Maria; Ogawa, Yoko; Perez, Victor; Uchino, Yuichi; Yokoi, Norihiko; Zoukhri, Driss; Sullivan, David A

    2017-07-01

    The TFOS DEWS II Pathophysiology Subcommittee reviewed the mechanisms involved in the initiation and perpetuation of dry eye disease. Its central mechanism is evaporative water loss leading to hyperosmolar tissue damage. Research in human disease and in animal models has shown that this, either directly or by inducing inflammation, causes a loss of both epithelial and goblet cells. The consequent decrease in surface wettability leads to early tear film breakup and amplifies hyperosmolarity via a Vicious Circle. Pain in dry eye is caused by tear hyperosmolarity, loss of lubrication, inflammatory mediators and neurosensory factors, while visual symptoms arise from tear and ocular surface irregularity. Increased friction targets damage to the lids and ocular surface, resulting in characteristic punctate epithelial keratitis, superior limbic keratoconjunctivitis, filamentary keratitis, lid parallel conjunctival folds, and lid wiper epitheliopathy. Hybrid dry eye disease, with features of both aqueous deficiency and increased evaporation, is common and efforts should be made to determine the relative contribution of each form to the total picture. To this end, practical methods are needed to measure tear evaporation in the clinic, and similarly, methods are needed to measure osmolarity at the tissue level across the ocular surface, to better determine the severity of dry eye. Areas for future research include the role of genetic mechanisms in non-Sjögren syndrome dry eye, the targeting of the terminal duct in meibomian gland disease and the influence of gaze dynamics and the closed eye state on tear stability and ocular surface inflammation. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Predicting acid dew point with a semi-empirical model

    International Nuclear Information System (INIS)

    Xiang, Baixiang; Tang, Bin; Wu, Yuxin; Yang, Hairui; Zhang, Man; Lu, Junfu

    2016-01-01

    Highlights: • The previous semi-empirical models are systematically studied. • An improved thermodynamic correlation is derived. • A semi-empirical prediction model is proposed. • The proposed semi-empirical model is validated. - Abstract: Decreasing the temperature of exhaust flue gas in boilers is one of the most effective ways to further improve the thermal efficiency, electrostatic precipitator efficiency and to decrease the water consumption of desulfurization tower, while, when this temperature is below the acid dew point, the fouling and corrosion will occur on the heating surfaces in the second pass of boilers. So, the knowledge on accurately predicting the acid dew point is essential. By investigating the previous models on acid dew point prediction, an improved thermodynamic correlation formula between the acid dew point and its influencing factors is derived first. And then, a semi-empirical prediction model is proposed, which is validated with the data both in field test and experiment, and comparing with the previous models.

  8. Control of dew and frost formation on leaf by radiative cooling

    International Nuclear Information System (INIS)

    Matsui, T.; Eguchi, H.; Mori, K.

    1981-01-01

    A radiative cooling system was developed to control dew and frost formations and to examine the effect of the radiative cooling on the leaf temperature. The growth chamber was provided with a box which was constructed by using heat insulating materials to minimize the disturbances and to regulate the air current. A cooling coil (cooling surface of 300 cm was equipped at the bottom of the box and manipulated by a refrigerator of 1, 430 kcal hour -1 , and a concave mirror was attached to the ceiling of the box to facilitate the reflection of the radiation from the leaf to the cooling coil. The moisture in air was supplied by flowing the controlled air (0.2 m min -1 ) into the box. The distribution of dew point temperatures was almost uniform horizontally even under vertically slight conversion (downward velocity of 1.3 cm sec -1 ) of the air. The leaf temperature became about 1.0°C lower than the ambient air temperature under the radiative cooling. The dew and the frost were clearly observed on the leaf after the time when the leaf temperature had become lower than the dew point temperature. The dew increased in size in course of time, and the frost varied in shape and in size with the temperatures. Thus, artificial formations of the dew and the frost were made possible by the radiative cooling system developed in this experiment

  9. Measuring the exhaust gas dew point of continuously operated combustion plants

    Energy Technology Data Exchange (ETDEWEB)

    Fehler, D.

    1985-07-16

    Low waste-gas temperatures represent one means of minimizing the energy consumption of combustion facilities. However, condensation should be prevented to occur in the waste gas since this could result in a destruction of parts. Measuring the waste-gas dew point allows to control combustion parameters in such a way as to be able to operate at low temperatures without danger of condensation. Dew point sensors will provide an important signal for optimizing combustion facilities.

  10. Integrated CMOS dew point sensors for relative humidity measurement

    Science.gov (United States)

    Savalli, Nicolo; Baglio, Salvatore; Castorina, Salvatore; Sacco, Vincenzo; Tringali, Cristina

    2004-07-01

    This work deals with the development of integrated relative humidity dew point sensors realized by adopting standard CMOS technology for applications in various fields. The proposed system is composed by a suspended plate that is cooled by exploiting integrated Peltier cells. The cold junctions of the cells have been spread over the plate surface to improve the homogeneity of the temperature distribution over its surface, where cooling will cause the water condensation. The temperature at which water drops occur, named dew point temperature, is a function of the air humidity. Measurement of such dew point temperature and the ambient temperature allows to know the relative humidity. The detection of water drops is achieved by adopting a capacitive sensing strategy realized by interdigited fixed combs, composed by the upper layer of the adopted process. Such a capacitive sensor, together with its conditioning circuit, drives a trigger that stops the cooling of the plate and enables the reading of the dew point temperature. Temperature measurements are achieved by means of suitably integrated thermocouples. The analytical model of the proposed system has been developed and has been used to design a prototype device and to estimate its performances. In such a prototype, the thermoelectric cooler is composed by 56 Peltier cells, made by metal 1/poly 1 junctions. The plate has a square shape with 200 μm side, and it is realized by exploiting the oxide layers. Starting from the ambient temperature a temperature variation of ΔT = 15 K can be reached in 10 ms thus allowing to measure a relative humidity greater than 40%.

  11. Simulations of tokamak disruptions including self-consistent temperature evolution

    International Nuclear Information System (INIS)

    Bondeson, A.

    1986-01-01

    Three-dimensional simulations of tokamaks have been carried out, including self-consistent temperature evolution with a highly anisotropic thermal conductivity. The simulations extend over the transport time-scale and address the question of how disruptive current profiles arise at low-q or high-density operation. Sharply defined disruptive events are triggered by the m/n=2/1 resistive tearing mode, which is mainly affected by local current gradients near the q=2 surface. If the global current gradient between q=2 and q=1 is sufficiently steep, the m=2 mode starts a shock which accelerates towards the q=1 surface, leaving stochastic fields, a flattened temperature profile and turbulent plasma behind it. For slightly weaker global current gradients, a shock may form, but it will dissipate before reaching q=1 and may lead to repetitive minidisruptions which flatten the temperature profile in a region inside the q=2 surface. (author)

  12. The Effect of Climate Change on Variations in Dew Amount in a Paddy Ecosystem of the Sanjiang Plain, China

    Directory of Open Access Journals (Sweden)

    Yingying Xu

    2015-01-01

    Full Text Available Due to global warming, a drying and warming trend has been observed over the last 50 years in the Sanjiang Plain of Heilongjiang Province, China, which could significantly affect the condensation of vapor in paddy ecosystems. Dew is a crucial factor in the water and nutrient cycling of farmland ecosystems, and it exerts an important influence on fertilization and other agricultural activities. In order to reveal the effects of global warming on dew variation in a paddy ecosystem, an in situ experiment was conducted in paddy fields in the Sanjiang Plain during the growing seasons of 2011 to 2013. Dew was collected and measured with a poplar stick. The results of correlation analysis between meteorological factors and dew intensity in the paddy ecosystem indicate that the dew point temperature and relative humidity significantly influenced the dew intensity. Based on synchronous meteorological data, a stepwise linear multivariation regression model was established to predict dew amount. The model successfully interpreted the relationship between simulated and measured dew intensity. The results suggest that a warmer and drier climate would lead to a reduction in dew amount because water cannot condense when relative humidity falls below 71%.

  13. Urban dew and rain in Paris, France: Occurrence and physico-chemical characteristics

    Science.gov (United States)

    Beysens, D.; Mongruel, A.; Acker, K.

    2017-06-01

    This paper summarizes one year (April 2011 to March 2012) measurements on planar condensing surfaces of dew and rain events and related physico-chemical characteristics in the urban environment of Paris (city center). Yearly collected water was 3.48 mm for dew (63 events) and 593 mm for rain (146 events). The latter value compares well with rain data (547 mm and 107 events) collected within 12 km at Paris-Orly airport. An estimation of dew yield based on meteo data gives 2.35 mm and 74 events, to be compared with 17.11 mm and 196 events at Paris-Orly. These differences highlight the large reduction in dew events and dew yields in an urban area as compared to a close rural-like area. This reduction is not due to a sky view reduction but to heat island that increases air temperature and decreases relative humidity. Analysis of dew (34) and rain (77) samples were done concerning pH, electrical conductivity (EC), major anions and cations as well as selected trace metals and other minor ions. Mean pH values are found similar for both, dew (6.5) and rain (6.1), rain being slightly more acidic than dew. The mean dew total ionic content (TIC 1.8 meq/l) and EC value (124 μS/cm) are about four times that of rain (0.45 meq/l; 35 μS/cm), meaning that total dissolved solids in dew is nearly four times that in rain. Sulfate and nitrate are the most acidifying components, calcium the most neutralizing constituent with ratio of mean total acidity/total alkalinity comparable for dew and rain ( 0.9). Sulfate and nitrate have mainly anthropogenic sources, whereas chloride and magnesium are mostly connected with marine air masses. Dew is a considerable factor of wet deposition of pollutants; dew and rain ion concentrations, however, meet the WHO requirements for drinking water.

  14. On the contribution of atmospheric moisture to dew formation

    Science.gov (United States)

    Garratt, J. R.; Segal, M.

    1988-09-01

    The relative contributions of dewfall (a flux of water vapour from air to surface) and distillation (a flux of water vapour from soil to canopy) to dew formation on closed canopy and bare soil surfaces are assessed, and the dependence of dew amount upon wind speed, absolute temperature, atmospheric stability, relative humidity, soil characteristics and cloudiness, all of which are significant factors, is evaluated. Some of these evaluations provide refinements to similar ones given in Monteith (1961). High dewfall rates are usually ≲0.06 mm hr-1 over canopy or bare soil, though upon a canopy under soil-saturated and air-saturated conditions, rates of dew formation may reach 0.07 0.09 mm hr-1 with contributions from distillation. Various sets of observations are reanalyzed to illustrate the importance of the horizontal advection of moisture in the nocturnal boundary layer (NBL) to observed high rates of dew formation arising from the atmospheric contribution of water vapour (dewfall). These locally observed high dewfall rates must be the result of small-scale or mesoscale horizontal advection of moisture in the NBL, since the humidity changes within the typically shallow NBL required to balance the loss of water at the surface are not observed. Over extensive areas of uniform surface (horizontal scales ≫10 km), such continuously high dewfall rates could only be balanced by a local supply of atmospheric moisture since advection of moisture would necessarily be small.

  15. Mechanism research on coupling effect between dew point corrosion and ash deposition

    International Nuclear Information System (INIS)

    Wang, Yun-Gang; Zhao, Qin-Xin; Zhang, Zhi-Xiang; Zhang, Zhi-Chao; Tao, Wen-Quan

    2013-01-01

    In order to study the coupling mechanism between ash deposition and dew point corrosion, five kinds of tube materials frequently used as anti-dew point corrosion materials were selected as research objects. Dew point corrosion and ash deposition experiments were performed with a new type experimental device in a Chinese thermal power plant. The microstructures of the materials and the composition of ash deposition were analyzed by X-ray diffraction (XRD) and Energy Dispersive Spectrometer (EDS). The results showed that the ash deposition layer could be divided into non-condensation zone, the main condensation zone and the secondary condensation zone. The acid vapor condensed in the main condensation zone rather than directly on the tube wall surface. The dew point corrosion mainly is oxygen corrosion under the condition of the viscosity ash deposition, and the corrosion products are composed of the ash and acid reaction products in the outer layer, iron sulfate in the middle layer, and iron oxide in the inner layer. The innermost layer is the main corrosion layer. With the increase of the tube wall temperature, the ash deposition changes from the viscosity ash deposition to the dry loose ash deposition, the ash deposition rate decreases dramatically and dew point corrosion is alleviated efficiently. The sulfuric dew point corrosion resistance of the five test materials is as follows: 316L > ND > Corten>20G > 20 steel. -- Highlights: ► Dew point corrosion and ash deposition tests of five materials were performed. ► Acid vapor condensed in the ash deposit rather than directly on the tube surface. ► Dew point corrosion resistance is as follow: 316L > ND > Corten>20G > 20 steel. ► Dew point corrosion mainly is oxygen corrosion under viscosity ash deposition

  16. Dew point measurements of flue gases in steam generators with brown coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Schinkel, W.

    1980-01-01

    This paper examines empirical data on sulfuric acid condensation and resulting internal corrosion in brown coal fired steam generators. Due to the high sulfur content in brown coal (0.5% to 5.0%) and relative short duration of the gases in the combustion chamber the concentrations of sulfur trioxide present in the flue gases can condense at the heat exchange surfaces of the steam generators. A number of diagrams show sulfuric acid dew point temperatures depending on brown coal sulfur content, the influence of combustion air supply on the dew point, and condensing speed and the rate of corrosion in relation to different heat exchange surface temperatures. The conclusion is made that a five-fold increase in corrosion can be caused by a 10 K higher flue gas dew point, a 5 K cooling of heating surfaces can also cause heavy corrosion at a certain dew point. Maximum corrosion results at 20 to 50 K differences between flue gas dew point and heat exchange surfaces. Optimum operation of steam generators with minimal internal corrosion requires the consideration of flue gas and heating surface temperatures as well as flue gas sulfur acid dew points. (10 refs.) (In German)

  17. Theory of acid deposition and its application to the dew-point meter

    Energy Technology Data Exchange (ETDEWEB)

    Land, T.

    1977-06-01

    The theory of convective mass transfer is used to calculate the rate of deposition of sulphuric acid on cooled surfaces in boiler flues. The mass deposited per unit area per second is ah/c (p/sub Ag/ - p/sub As/) where h is the coefficient of convective heat transfer, c is the specific heat of the gas and a is a factor having a value of about 1.9; p/sub Ag/ and p/sub As/ are the partial pressures of sulphuric acid in the bulk of the gas and in saturated gas at the temperature of the surface. Values of p/sub A/ are tabulated against dew-point temperature and water vapour content. The theory explains how fog formation in the gas reduces the rate of acid deposition within a certain band of temperature between the acid dew-point and the water dew-point. The rate of deposition on a probe is shown to depend on the local mass flow as well as on the acid content. By contrast the dew-point depends only on the acid content. The sensitivity of the dew-point meter to changes in acid content is not very high but it is adequate for the control of combustion. A continuously recording dew-point meter is being successfully used on industrial boilers.

  18. Transient performance of integrated SOFC system including spatial temperature control

    OpenAIRE

    Mueller, F; Fardadi, M; Shaffer, B; Brouwer, J; Jabbari, F

    2010-01-01

    Spatial temperature feedback control has been developed for a simulated integrated non-pressurized simple cycle solid oxide fuel cell (SOFC) system. The fuel cell spatial temperature feedback controller is based on (1) feed-forward set-points that minimize temperature variation in the fuel cell electrode-electrolyte solid temperature profile for the system operating power range, and (2) decentralized proportional-integral based feedback to maintain the fuel cell spatial temperature profile du...

  19. Multiobjective optimization in Gene Expression Programming for Dew Point

    OpenAIRE

    Shroff, Siddharth; Dabhi, Vipul

    2013-01-01

    The processes occurring in climatic change evolution and their variations play a major role in environmental engineering. Different techniques are used to model the relationship between temperatures, dew point and relative humidity. Gene expression programming is capable of modelling complex realities with great accuracy, allowing, at the same time, the extraction of knowledge from the evolved models compared to other learning algorithms. This research aims to use Gene Expression Programming ...

  20. Effects of temperature at constant air dew point on leaf carboxylation efficiency and CO2 compensation point of different leaf types.

    Science.gov (United States)

    Weber, J A; Tenhunen, J D; Lange, O L

    1985-09-01

    The effect of temperature on photosynthesis at constant water-vapor pressure in the air was investigated using two sclerophyll species, Arbutus unedo and Quercus suber, and one mesophytic species, Spinacia oleracea. Photosynthesis and transpiration were measured over a range of temperatures, 20-39° C. The external concentration of CO2 was varied from 340 μbar to near CO2 compensation. The initial slope (carboxylation efficiency, CE) of the photosynthetic response to intercellular CO2 concentration, the CO2 compensation point (Γ), and the extrapolated rate of CO2 released into CO2-free air (R i) were calculated. At an external CO2 concentration of 320-340 μbar CO2, photosynthesis decreased with temperature in all species. The effect of temperature on Γ was similar in all species. While CE in S. oleracea changed little with temperature, CE decreased by 50% in Q. suber as temperature increased from 25 to 34° C. Arbutus unedo also exhibited a decrease in CE at higher temperatures but not as marked as Q. suber. The absolut value of R i increased with temperature in S. oleracea, while changing little or decreasing in the sclerophylls. Variations in Γ and R i of the sclerophyll species are not consistent with greater increase of respiration with temperature in the light in these species compared with S. oleracea.

  1. Dew point of flue gas in the combustion of brown coal briquettes

    Energy Technology Data Exchange (ETDEWEB)

    Schinkel, W

    1977-08-01

    Economical operation of small steam generators can follow two courses, viz. to channel the emitted gases through the plant and reduce waste gas loss. Two possibilities exist to achieve this: firstly a steam generating process with only slight excess air; secondly a reduction of the emitted gas temperature. The lowest waste gas temperature found in sulphur-containing combustion materials is measured by finding the acid dew-point of the waste gas. The following results in the case of brown coal briquettes were found. Measurements of the dew point of flue gas in two steam generators, both of the double flue type, one having a capacity of 12.5 t/h, the other 25 t/h, one using brown coal briquettes with 1% sulphur content, the other with 3%, resulted in the fact that the dew point can be measured. It was shown that a low air ratio leads to a lowering of the dew point. However this process is unfortunately economically unviable in chain grate generators as the waste gas becomes so thin under a high air ratio that the dew point can only be minimally reduced. Further the acid dew point is only slightly influenced by partial operation of the generator and the infusion of briquette residue.

  2. Contribution to the study of sulfur trioxide formation and determination of the sulfuric acid dew point in boiler plants

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, H.

    1983-11-01

    This paper analyzes chemical reaction kinetics of the formation of sulfur trioxide and sulfuric acid in combustion air and flue gas of steam generators. Formulae for sulfuric acid equilibrium reactions according to Wahnschaffe (W. Grimm, 1972) and R. Hasse, H.W. Borgmann (1962) are presented. Theoretical acid dew point, combustion parameters with influence on the dew point temperature and formation of sulfates are further discussed. Sulfur trioxide formation at temperatures above 1,000 C as a non-equilibrium reaction is outlined as another variant of chemical reactions. A graphic evaluation is made of dew point conditions in brown coal dust fired, and heating oil fired steam generators. (11 refs.)

  3. Unsteady-state analysis of a counter-flow dew point evaporative cooling system

    KAUST Repository

    Lin, J.

    2016-07-19

    Understanding the dynamic behavior of the dew point evaporative cooler is crucial in achieving efficient cooling for real applications. This paper details the development of a transient model for a counter-flow dew point evaporative cooling system. The transient model approaching steady conditions agreed well with the steady state model. Additionally, it is able to accurately predict the experimental data within 4.3% discrepancy. The transient responses of the cooling system were investigated under different inlet air conditions. Temporal temperature and humidity profiles were analyzed for different transient and step responses. The key findings from this study include: (1) the response trend and settling time is markedly dependent on the inlet air temperature, humidity and velocity; (2) the settling time of the transient response ranges from 50 s to 300 s when the system operates under different inlet conditions; and (3) the average transient wet bulb effectiveness (1.00–1.06) of the system is observed to be higher than the steady state wet bulb effectiveness (1.01) for our range of study. © 2016 Elsevier Ltd

  4. The measurement of tiny dew droplets at the initial deposition stage and dew point using a phase-shift interference microscope

    Science.gov (United States)

    Shigeaki, Matsumoto

    2003-12-01

    The shape of a dew droplet deposited on the mirror surface of a copper plate was measured accurately using an interference microscope that employed a phase-shift technique. The microscope was constructed by adding a piezoelectric transducer to an interference microscope. A simple method that uses a conventional speaker horn and an optical fibre cable was used to depress any speckle noise. The shape of a dew droplet deposited at dew point on the plate surface with average roughness of 0.1 µm was measured with an accuracy of ± 3 nm. The mass of a tiny dew droplet could be determined from the volume of its shape and was of the order of 10-9 g. The total mass of a dew droplet deposited per unit area and the deposition velocity under a gentle wind were also obtained in a similar way. The total mass was of the order of 10-5 g cm-2 at the beginning of deposition and the deposition velocity ranged from 1 × 10-5 to 6 × 10-5 g cm-2 min-1 at room temperature.

  5. Fog and dew climatology over Hisar, India

    International Nuclear Information System (INIS)

    Surender, S.; Diwan, S.; Rao, V.U.M.

    2006-05-01

    In many arid and semi-arid areas, pumped ground water and the water from streams, rivers and reservoirs is no longer sufficient to cover the ever increasing water demand. Therefore new interest in 'marginal' water resources like fog and dew harvesting are to be developed after studying climatology of these parameters in a region. The observations on dew and fog events recorded at Hisar, representing semi-arid region of India during winter season (October to March) for the period 1980 to 2005 have been analyzed. The total annual dew amount in winter season ranged between 33 mm (1987-88) and 79 mm (1981-82) during the period under study. The seasonal dewfall showed a decreasing trend of 1.4 mm during the period under investigation. Average maximum dew events (26.1) were recorded during November and average minimum dew events were recorded in February. In a particular season, the highest dew events (168) were observed during the winter seasons of 1982-83 and 1983-84, whereas, the minimum number of dew events (97) was reported during 1998-99. Interestingly, an increasing trend (1.3 day/season) in occurrence of fog events was seen. Average maximum foggy events (8.7) recorded in a month were observed in January. In a particular season, the maximum foggy events (41) were recorded during 2002-03 and the minimum (2) during 1983-84. To achieve the objective of alternate source of water and to assess the impact of dew and fog on agricultural crops for their growth and development, inputs from various specialized disciplines and allied sciences engaged in meteorological applications along with forecasting skills from non scientific quarters are needed to predict the weather parameter accurately, thus the active cooperation between meteorological/remote sensing agencies, agricultural organizations and farming community is needed for sustainable agricultural development in scarce/limited water availability regions. (author)

  6. Note: A dual-channel sensor for dew point measurement based on quartz crystal microbalance

    Science.gov (United States)

    Li, Ning; Meng, Xiaofeng; Nie, Jing

    2017-05-01

    A new sensor with dual-channel was designed for eliminating the temperature effect on the frequency measurement of the quartz crystal microbalance (QCM) in dew point detection. The sensor uses active temperature control, produces condensation on the surface of QCM, and then detects the dew point. Both the single-channel and the dual-channel methods were conducted based on the device. The measurement error of the single-channel method was less than 0.5 °C at the dew point range of -2 °C-10 °C while the dual-channel was 0.3 °C. The results showed that the dual-channel method was able to eliminate the temperature effect and yield better measurement accuracy.

  7. An ultrahigh-accuracy Miniature Dew Point Sensor based on an Integrated Photonics Platform

    Science.gov (United States)

    Tao, Jifang; Luo, Yu; Wang, Li; Cai, Hong; Sun, Tao; Song, Junfeng; Liu, Hui; Gu, Yuandong

    2016-07-01

    The dew point is the temperature at which vapour begins to condense out of the gaseous phase. The deterministic relationship between the dew point and humidity is the basis for the industry-standard “chilled-mirror” dew point hygrometers used for highly accurate humidity measurements, which are essential for a broad range of industrial and metrological applications. However, these instruments have several limitations, such as high cost, large size and slow response. In this report, we demonstrate a compact, integrated photonic dew point sensor (DPS) that features high accuracy, a small footprint, and fast response. The fundamental component of this DPS is a partially exposed photonic micro-ring resonator, which serves two functions simultaneously: 1) sensing the condensed water droplets via evanescent fields and 2) functioning as a highly accurate, in situ temperature sensor based on the thermo-optic effect (TOE). This device virtually eliminates most of the temperature-related errors that affect conventional “chilled-mirror” hygrometers. Moreover, this DPS outperforms conventional “chilled-mirror” hygrometers with respect to size, cost and response time, paving the way for on-chip dew point detection and extension to applications for which the conventional technology is unsuitable because of size, cost, and other constraints.

  8. Dew and hoarfrost frequency, formation efficiency and chemistry in Wroclaw, Poland

    Science.gov (United States)

    Gałek, G.; Sobik, M.; Błaś, M.; Polkowska, Ż.; Cichała-Kamrowska, K.; Wałaszek, K.

    2015-01-01

    This article presents the results of a research study concerning a comparison of frequency, formation efficiency and basic physico-chemical properties of dew and hoarfrost in urban conditions. Longer than two-year series of measurements was carried out from 1 February 2008 to 10 March 2010 in Wroclaw, Poland. Sampling of atmospheric deposits was made by means of insulated plain passive radiative condensers, which allowed to collect 222 dew and 96 hoarfrost samples. The results indicate that the frequency of dew days was about threefold greater than hoarfrost days. The formation efficiency of both types of deposits was almost the same, and reached a mean value of about 100 mL·m- 2 per day. The conducted analysis of several meteorological parameters showed that dew and hoarfrost, despite seasonal weather changes, were formed in very similar meteorological conditions. Only water vapor pressure values were in average twice higher in the case of dew and the impact of this parameter on dew and hoarfrost formation efficiency seems to be more complex than expected. The role of night duration in counterbalancing of smaller amount of available moisture in hoarfrost days is not clear. The investigation showed also, that there was an expected clear positive dependence of dew and hoarfrost formation efficiency on relative humidity, and not so evident in the case of temperature inversion, and wind velocity. The physico-chemical analysis indicated that the pH of dew was only slightly lower than the hoarfrost ones, regardless of the deposit formation intensity. Simultaneously, the lower pH values were much more frequent in the case of dew, which resulted from more effective absorption of anthropogenic NO3- and SO42 - ions. For both types of deposits, the average pH was low (4.5-4.8) in relation to majority of studies reported in literature. In spite of seasonal changes of pollutant concentration, various weather conditions and different mechanisms of pollutant absorption of dew

  9. A novel method of measuring the concentration of anaesthetic vapours using a dew-point hygrometer.

    Science.gov (United States)

    Wilkes, A R; Mapleson, W W; Mecklenburgh, J S

    1994-02-01

    The Antoine equation relates the saturated vapour pressure of a volatile substance, such as an anaesthetic agent, to the temperature. The measurement of the 'dew-point' of a dry gas mixture containing a volatile anaesthetic agent by a dew-point hygrometer permits the determination of the partial pressure of the anaesthetic agent. The accuracy of this technique is limited only by the accuracy of the Antoine coefficients and of the temperature measurement. Comparing measurements by the dew-point method with measurements by refractometry showed systematic discrepancies up to 0.2% and random discrepancies with SDS up to 0.07% concentration in the 1% to 5% range for three volatile anaesthetics. The systematic discrepancies may be due to errors in available data for the vapour pressures and/or the refractive indices of the anaesthetics.

  10. TFOS DEWS II Definition and Classification Report.

    Science.gov (United States)

    Craig, Jennifer P; Nichols, Kelly K; Akpek, Esen K; Caffery, Barbara; Dua, Harminder S; Joo, Choun-Ki; Liu, Zuguo; Nelson, J Daniel; Nichols, Jason J; Tsubota, Kazuo; Stapleton, Fiona

    2017-07-01

    The goals of the TFOS DEWS II Definition and Classification Subcommittee were to create an evidence-based definition and a contemporary classification system for dry eye disease (DED). The new definition recognizes the multifactorial nature of dry eye as a disease where loss of homeostasis of the tear film is the central pathophysiological concept. Ocular symptoms, as a broader term that encompasses reports of discomfort or visual disturbance, feature in the definition and the key etiologies of tear film instability, hyperosmolarity, and ocular surface inflammation and damage were determined to be important for inclusion in the definition. In the light of new data, neurosensory abnormalities were also included in the definition for the first time. In the classification of DED, recent evidence supports a scheme based on the pathophysiology where aqueous deficient and evaporative dry eye exist as a continuum, such that elements of each are considered in diagnosis and management. Central to the scheme is a positive diagnosis of DED with signs and symptoms, and this is directed towards management to restore homeostasis. The scheme also allows consideration of various related manifestations, such as non-obvious disease involving ocular surface signs without related symptoms, including neurotrophic conditions where dysfunctional sensation exists, and cases where symptoms exist without demonstrable ocular surface signs, including neuropathic pain. This approach is not intended to override clinical assessment and judgment but should prove helpful in guiding clinical management and research. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Numerical study of a novel counter-flow heat and mass exchanger for dew point evaporative cooling

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, X.; Riffat, S.B. [School of the Built Environment, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom); Li, J.M. [Department of Thermal Engineering, Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Tsinghua University, Beijing 100084 (China)

    2008-10-15

    The paper presents numerical investigation of a novel counter-flow heat and mass exchanger used in the indirect evaporative dew point cooling systems, a potential alternative to the conventional mechanical compression air conditioning systems. Numeric simulation was carried out to optimise the geometrical sizes and operating conditions of the exchanger in order to enhance the cooling (dew point and wet bulb) effectiveness of the exchanger and maximise the energy efficiency of the dew point cooling system. The results of the simulations indicated that cooling (dew point and wet bulb) effectiveness and energy efficiency are largely dependent on the dimensions of the airflow passages, air velocity and working-to-intake-air ratio, and less dependent on the temperature of the feed water. It is recommended that exchanger intake air velocity should be controlled to a value below 0.3-0.5 m/s; height of air passage (channel) should be set to 6 mm or below and the length of the passage should be 200 time the height; the working-to-intake-air ratio should be around 0.4. Under the UK summer design condition, i.e., 28{sup o}C of dry bulb temperature, 20{sup o}C of wet bulb temperature and 16{sup o}C of dew point temperature, the exchanger can achieve wet-bulb effectiveness of up to 1.3 and dew-point effectiveness of up to 0.9. (author)

  12. Analysis of Multicomponent Adsorption Close to a Dew Point

    DEFF Research Database (Denmark)

    Shapiro, Alexander; Stenby, Erling Halfdan

    1998-01-01

    We develop the potential theory of multicomponent adsorption close to a dew point. The approach is based on an asymptotic adsorption equation (AAE) which is valid in a vicinity of the dew point. By this equation the thickness of the liquid film is expressed through thermodynamic characteristics...... and the direct calculations, even if the mixture is not close to a dew point.Key Words: adsorption; potential theory; multicomponent; dew point....

  13. Estimation of combustion flue gas acid dew point during heat recovery and efficiency gain

    Energy Technology Data Exchange (ETDEWEB)

    Bahadori, A. [Curtin University of Technology, Perth, WA (Australia)

    2011-06-15

    When cooling combustion flue gas for heat recovery and efficiency gain, the temperature must not be allowed to drop below the sulfur trioxide dew point. Below the SO{sub 3} dew point, very corrosive sulfuric acid forms and leads to operational hazards on metal surfaces. In the present work, simple-to-use predictive tool, which is easier than existing approaches, less complicated with fewer computations is formulated to arrive at an appropriate estimation of acid dew point during combustion flue gas cooling which depends on fuel type, sulfur content in fuel, and excess air levels. The resulting information can then be applied to estimate the acid dew point, for sulfur in various fuels up to 0.10 volume fraction in gas (0.10 mass fraction in liquid), excess air fractions up to 0.25, and elemental concentrations of carbon up to 3. The proposed predictive tool shows a very good agreement with the reported data wherein the average absolute deviation percent was found to be around 3.18%. This approach can be of immense practical value for engineers and scientists for a quick estimation of acid dew point during combustion flue gas cooling for heat recovery and efficiency gain for wide range of operating conditions without the necessity of any pilot plant setup and tedious experimental trials. In particular, process and combustion engineers would find the tool to be user friendly involving transparent calculations with no complex expressions for their applications.

  14. KEY COMPARISON Report to the CCT on key comparison EUROMET.T-K6 (EUROMET Project no. 621): Comparison of the realizations of local dew/frost-point temperature scales in the range -50 °C to +20 °C

    Science.gov (United States)

    Heinonen, Martti

    2010-01-01

    The first humidity CIPM key comparison, CCT-K6, will be completed in 2010. The corresponding European regional key comparison, EUROMET.T-K6, was carried out in 2004 to 2008. National metrology institutes from 24 countries participated in the comparison. The comparison covered the dew-point temperature range from -50 °C to +20 °C. It was organized as three parallel loops with two specially manufactured precision chilled mirror hygrometers as transfer standards in each loop. The comparison scheme was designed to ensure high quality results with evenly spread workload for the participants. MIKES was coordinating the project. This report presents the results of the comparison and provides detailed information on the measurements performed by all participating laboratories and the analysis of the results. Conclusions on the equivalence of the dew-point temperature standards are drawn on the basis of calculated bilateral degrees of equivalence and deviations from EURAMET comparison reference values (ERV). Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  15. TFOS DEWS II Tear Film Report.

    Science.gov (United States)

    Willcox, Mark D P; Argüeso, Pablo; Georgiev, Georgi A; Holopainen, Juha M; Laurie, Gordon W; Millar, Tom J; Papas, Eric B; Rolland, Jannick P; Schmidt, Tannin A; Stahl, Ulrike; Suarez, Tatiana; Subbaraman, Lakshman N; Uçakhan, Omür Ö; Jones, Lyndon

    2017-07-01

    The members of the Tear Film Subcommittee reviewed the role of the tear film in dry eye disease (DED). The Subcommittee reviewed biophysical and biochemical aspects of tears and how these change in DED. Clinically, DED is characterized by loss of tear volume, more rapid breakup of the tear film and increased evaporation of tears from the ocular surface. The tear film is composed of many substances including lipids, proteins, mucins and electrolytes. All of these contribute to the integrity of the tear film but exactly how they interact is still an area of active research. Tear film osmolarity increases in DED. Changes to other components such as proteins and mucins can be used as biomarkers for DED. The Subcommittee recommended areas for future research to advance our understanding of the tear film and how this changes with DED. The final report was written after review by all Subcommittee members and the entire TFOS DEWS II membership. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Effects of sand burial on dew deposition on moss soil crust in a revegetated area of the Tennger Desert, Northern China

    Science.gov (United States)

    Jia, Rong-liang; Li, Xin-rong; Liu, Li-chao; Pan, Yan-xia; Gao, Yan-hong; Wei, Yong-ping

    2014-11-01

    Sand burial and dew deposition are two fundamental phenomena profoundly influencing biological soil crusts in desert areas. However, little information is available regarding the effects of sand burial on dew deposition on biological soil crusts in desert ecosystems. In this study, we evaluated the effects of sand burial at depths of 0 (control), 0.5, 1, 2 and 4 mm on dew formation and evaporation of three dominant moss crusts in a revegetated area of the Tengger Desert (Northern China) in 2010. The results revealed that sand burial significantly decreased the amount of dew deposited on the three moss crust types by acting as a semi-insulator retarding the dew formation and evaporation rates. The changes in surface temperature cannot fully explain the variations of the formation and evaporation rates of dew by moss crusts buried by sand. The extension of dew retention time was reflected by the higher dew ratios (the ratio of dew amount at a certain time to the maximum value in a daily course) in the daytime, and may to some extent have acted as compensatory mechanisms that diminished the negative effects of the reduction of dew amount induced by sand burial of moss crusts. The resistances to reduction of dewfall caused by sand burial among the three moss crusts were also compared and it was found that Bryum argenteum crust showed the highest tolerance, followed by crusts dominated by Didymodon vinealis and Syntrichia caninervis. This sequence corresponds well with the successional order of the three moss crusts in the revegetated area, thereby suggesting that resistance to reduction of dewfall may act as one mechanism by which sand burial drives the succession of moss crusts in desert ecosystems. This side effect of dew reduction induced by sand burial on biological soil crusts should be considered in future ecosystem construction and management of desert area.

  17. Effects of dew point on selective oxidation of TRIP steels containing Si, Mn, and B

    Science.gov (United States)

    Lee, Suk-Kyu; Kim, Jong-Sang; Choi, Jin-Won; Kang, Namhyun; Cho, Kyung-Mox

    2011-04-01

    The selective oxidation of Si, Mn, and B on TRIP steel surfaces is a widely known phenomenon that occurs during heat treatment. However, the relationship between oxide formation and the annealing factors is not completely understood. This study examines the effect of the annealing conditions (dew point and annealing temperature) on oxide formation. A low dew point of -40 °C leads to the formation of Si-based oxides on the surface. A high dew point of -20 °C changes the oxide type to Mn-based oxides because the formation of Si oxides on the surface is suppressed by internal oxidation. Mn-based oxides exhibit superior wettability due to aluminothermic reduction during galvanizing.

  18. An experimental study of a novel dew point evaporative cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Riangvilaikul, B.; Kumar, S. [Energy Field of Study, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120 (Thailand)

    2010-05-15

    A novel dew point evaporative cooling system for sensible cooling of the ventilation air for air conditioning application was constructed and experiments were carried out to investigate the outlet air conditions and the system effectiveness at different inlet air conditions (temperature, humidity and velocity) covering dry, temperate and humid climates. The results showed that wet bulb effectiveness ranged between 92 and 114% and the dew point effectiveness between 58 and 84%. A continuous operation of the system during a typical day of summer season in a hot and humid climate showed that wet bulb and dew point effectiveness were almost constant at about 102 and 76%, respectively. The experiment results were compared with some recent studies in literature. (author)

  19. A MEMS-based super fast dew point hygrometer—construction and medical applications

    International Nuclear Information System (INIS)

    Jachowicz, Ryszard S; Weremczuk, Jerzy; Paczesny, Daniel; Tarapata, Grzegorz

    2009-01-01

    The paper shows how MEMS (micro-electro-mechanical system) technology and a modified principle of fast temperature control (by heat injection instead of careful control of cooling) can considerably improve the dynamic parameters of dew point hygrometers. Some aspects of MEMS-type integrated sensor construction and technology, whole measurement system design, the control algorithm to run the system as well as empirical dynamic parameters from the tests are discussed too. The hygrometer can easily obtain five to six measurements per second with an uncertainty of less than 0.3 K. The meter range is between −10 °C and 40 °C dew point. In the second part of the paper (section 2), two different successful applications in medicine based on fast humidity measurements have been discussed. Some specific constructions of these super fast dew point hygrometers based on a MEMS sensor as well as limited empirical results from clinical tests have been reported too

  20. A MEMS-based super fast dew point hygrometer—construction and medical applications

    Science.gov (United States)

    Jachowicz, Ryszard S.; Weremczuk, Jerzy; Paczesny, Daniel; Tarapata, Grzegorz

    2009-12-01

    The paper shows how MEMS (micro-electro-mechanical system) technology and a modified principle of fast temperature control (by heat injection instead of careful control of cooling) can considerably improve the dynamic parameters of dew point hygrometers. Some aspects of MEMS-type integrated sensor construction and technology, whole measurement system design, the control algorithm to run the system as well as empirical dynamic parameters from the tests are discussed too. The hygrometer can easily obtain five to six measurements per second with an uncertainty of less than 0.3 K. The meter range is between -10 °C and 40 °C dew point. In the second part of the paper (section 2), two different successful applications in medicine based on fast humidity measurements have been discussed. Some specific constructions of these super fast dew point hygrometers based on a MEMS sensor as well as limited empirical results from clinical tests have been reported too.

  1. Evaluation of the physical dew point in the economizer of a combined cycle burning natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Pena, F.; Blanco, J.M. [Universidad del Pais Vasco/E.H.U. Alameda de Urquijo s/n, Bilbao (Spain). Dpto. Maquinas y Motores Termicos, Escuela Sup. de Ingenieria

    2007-08-15

    Natural gas contents a considerable percentage of hydrogen, so is obvious to expect an amount of water vapour in its combustion exhaust gases, which would raise the dew point temperature. That means a higher speed of corrosion over the whole exposed physical area, which could represent a serious risk of breakdown, especially in pressurized hot-water equipments. In this work, a new methodology for determining the physical dew point inside a economizer depending on the fuel type burned (in this case is natural gas) has been developed. The calculation of the total amount of condensed water has also been carried out as well as the localization of the area where this condensation occurs. Acid dew point has not been taken into account here although exhaust gases are acidic, due mainly to the low sulphur content which is almost undetectable when burning natural gas, but it will be performed in a later study coming soon. (author)

  2. A comparative study of compression-expansion type dehumidification systems to achieve low dew point air

    International Nuclear Information System (INIS)

    Moon, Choon; Bansal, Pradeep

    2009-01-01

    This paper presents a theoretical feasibility study of three dehumidification systems to achieve air with dew points down to (-) 40 deg. C. The systems consist of compressors, heat exchangers, expanders and heaters. A thermodynamic model has been developed of the systems to study the effect of the compressor, expander, and heat recovery heat exchanger efficiency as a function of pressure ratio, net required work, quantity of condensed moisture, and system outlet dew point temperature. The analysis has revealed that the selection of a heat recovery heat exchanger is critical for an efficient dehumidification system, where compressor efficiency has the dominant effect on power consumption.

  3. Concerning the acid dew point in waste gases from combustion processes

    Energy Technology Data Exchange (ETDEWEB)

    Knoche, K.F.; Deutz, W.; Hein, K.; Derichs, W.

    1986-09-01

    The paper discusses the problems associated with the measurement of acid dew point and of sulphuric acid-(say SO/sub 3/-)concentrations in the flue gas from brown coal-fired boiler plants. The sulphuric acid content in brown coal flue gas has been measured at 0.5 to 3 vpm in SO/sub 2/ concentrations of 200 to 800 vpm. Using a conditional equation, the derivation of which from new formulae for phase stability is described in the paper, an acid dew point temperature of 115 to 125/sup 0/C is produced.

  4. A sub-circuit MOSFET model with a wide temperature range including cryogenic temperature

    Energy Technology Data Exchange (ETDEWEB)

    Jia Kan; Sun Weifeng; Shi Longxing, E-mail: jiakan.01@gmail.com [National ASIC System Engineering Research Center, Southeast University, Nanjing 210096 (China)

    2011-06-15

    A sub-circuit SPICE model of a MOSFET for low temperature operation is presented. Two resistors are introduced for the freeze-out effect, and the explicit behavioral models are developed for them. The model can be used in a wide temperature range covering both cryogenic temperature and regular temperatures. (semiconductor devices)

  5. Dew Point Calibration System Using a Quartz Crystal Sensor with a Differential Frequency Method

    Directory of Open Access Journals (Sweden)

    Ningning Lin

    2016-11-01

    Full Text Available In this paper, the influence of temperature on quartz crystal microbalance (QCM sensor response during dew point calibration is investigated. The aim is to present a compensation method to eliminate temperature impact on frequency acquisition. A new sensitive structure is proposed with double QCMs. One is kept in contact with the environment, whereas the other is not exposed to the atmosphere. There is a thermal conductivity silicone pad between each crystal and a refrigeration device to keep a uniform temperature condition. A differential frequency method is described in detail and is applied to calibrate the frequency characteristics of QCM at the dew point of −3.75 °C. It is worth noting that frequency changes of two QCMs were approximately opposite when temperature conditions were changed simultaneously. The results from continuous experiments show that the frequencies of two QCMs as the dew point moment was reached have strong consistency and high repeatability, leading to the conclusion that the sensitive structure can calibrate dew points with high reliability.

  6. Dew Point Calibration System Using a Quartz Crystal Sensor with a Differential Frequency Method.

    Science.gov (United States)

    Lin, Ningning; Meng, Xiaofeng; Nie, Jing

    2016-11-18

    In this paper, the influence of temperature on quartz crystal microbalance (QCM) sensor response during dew point calibration is investigated. The aim is to present a compensation method to eliminate temperature impact on frequency acquisition. A new sensitive structure is proposed with double QCMs. One is kept in contact with the environment, whereas the other is not exposed to the atmosphere. There is a thermal conductivity silicone pad between each crystal and a refrigeration device to keep a uniform temperature condition. A differential frequency method is described in detail and is applied to calibrate the frequency characteristics of QCM at the dew point of -3.75 °C. It is worth noting that frequency changes of two QCMs were approximately opposite when temperature conditions were changed simultaneously. The results from continuous experiments show that the frequencies of two QCMs as the dew point moment was reached have strong consistency and high repeatability, leading to the conclusion that the sensitive structure can calibrate dew points with high reliability.

  7. Determination of the dew point and the frost point below 0 degrees C making use of the beta-ray backscattering and the electric conductivity on the narrow surface of insulated layer.

    Science.gov (United States)

    Matsumoto, S; Kobayashi, H

    1979-10-15

    It is necessary to distinguish between the dew point and the frost point below 0 degrees C. The freezing of the dew and the melting of the frost are respectively detected by the rapid decrease and the increase of the conduction current on the narrow surface of insulated layer made of epoxy, 0.5 mm in width and 10 mm in length, on which the dew deposits. The dew point -9 degrees C and the frost point -8 degrees C in the humidity 21% at the temperature 13 degrees C are clearly distinguished in this method.

  8. Applicability of a desiccant dew-point cooling system independent of external water sources

    DEFF Research Database (Denmark)

    Bellemo, Lorenzo; Elmegaard, Brian; Kærn, Martin Ryhl

    2015-01-01

    The applicability of a technical solution for making desiccant cooling systems independent of external water sources is investigated. Water is produced by condensing the desorbed water vapour in a closed regeneration circuit. Desorbed water recovery is applied to a desiccant dew-point cooling...... system, which includes a desiccant wheel and a dew point cooler. The system is simulated during the summer period in the Mediterranean climate of Rome and it results completely independent of external water sources. The seasonal thermal COP drops 8% in comparison to the open regeneration circuit solution...

  9. Application of passive radiative cooling for dew condensation

    International Nuclear Information System (INIS)

    Beysens, Daniel; Muselli, Marc; Milimouk, Iryna

    2006-01-01

    Dew water was collected from several passive foil-based radiative condensers established in a variety of geographic settings: continental (Grenoble, in an alpine valley, and Brive-la-Gaillarde, in the Central Massif volcanic area, both in France), French Atlantic coast (Bordeaux), eastern Mediterranean (Jerusalem, Israel), and the island of Corsica (Ajaccio, France) in the Mediterranean Sea. In Ajaccio two large 30 m 2 condensers have been operating since 2000. Additional semi-quantitative dew measurements were also carried out for Komiza, island of Vis (Croatia) in the Adriatic Sea, and in Mediterranean Zadar and Dubrovnik (both in Croatia). Dew potential was calculated for the Pacific Ocean island of Tahiti (French Polynesia). The data show that significant amounts of dew water can be collected. Selected chemical and biological analyses established that dew is, in general, potable. Continued research is required for new and inexpensive materials that can enhance dew condensation

  10. An automatic dew-point hygrometer making use of beta-ray backscattering

    International Nuclear Information System (INIS)

    Matsumoto, Sigeaki; Kobayashi, Hisanobu

    1981-01-01

    A proportional control system was employed on this hygrometer. The hygrometer was used in a box in which the temperature and the humidity were constantly regulated. The range of measured dew-point was from -26 0 C to 60 0 C in the atmospheric temperature of 0 0 C to 60 0 C, that was the relative humidity of 12% to 100%, and the accuracy of the measurement was +-1 0 C. (author)

  11. [An automatic dew-point hygrometer making use of beta-ray backscattering (author's transl)].

    Science.gov (United States)

    Matsumoto, S; Kobayashi, H

    1981-04-01

    A proportional control system was employed on this hygrometer. The hygrometer was used in a box in which the temperature and the humidity were constantly regulated. The range of measured dew-point was from -26 degrees C to 60 degrees C in the atmospheric temperature of 0 degree C to 60 degrees C, that was the relative humidity of 12% to 100%, and the accuracy of the measurement was +/- 1 degree C.

  12. Protection of HCl dew point corrosion in municipal incinerators

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, S.; Tsuruta, T.; Maeda, N.

    1976-12-01

    HCl dew point corrosion is often observed on the components of municipal incinerators used for burning wastes which contain polyvinyl chloride. In order to solve the problem, the relation between concentrations of gaseous HCl and the corresponding dew points as well as concentrations of condensed HCl, was investigated. A series of HCl dipping tests for the materials concerned was performed and the dip test results were compared with in-plant tests. As a result it was concluded that HCl dew point corrosion can be reliably predicted from measurements of HCl concentrations in the water and in the gas and the partial pressure of the saturated steam at the dew point.

  13. Densimetry for the Quantification of Sorption Phenomena on Nonporous Media Near the Dew Point of Fluid Mixtures.

    Science.gov (United States)

    Richter, Markus; McLinden, Mark O

    2017-07-21

    Phase equilibria of fluid mixtures are important in numerous industrial applications and are, thus, a major focus of thermophysical property research. Improved data, particularly along the dew line, are needed to improve model predictions. Here we present experimental results utilizing highly accurate densimetry to quantify the effects of sorption and capillary condensation, which exert a distorting influence on measured properties near the dew line. We investigate the (pressure, density, temperature, composition) behaviour of binary (CH 4  + C 3 H 8 ) and (Ar + CO 2 ) mixtures over the temperature range from (248.15 to 273.15) K starting at low pressures and increasing in pressure towards the dew point along isotherms. Three distinct regions are observed: (1) minor sorption effects in micropores at low pressures; (2) capillary condensation followed by wetting in macro-scale surface scratches beginning approximately 2% below the dew-point pressure; (3) bulk condensation. We hypothesize that the true dew point lies within the second region.

  14. Final report on EURAMET.T-K6.1: Bilateral comparison of the realisations of local dew/frost-point temperature scales in the range -70 °C to +20 °C

    Science.gov (United States)

    Heinonen, Martti; Zvizdic, Davor; Sestan, Danijel

    2013-01-01

    As the European extension of the first CCT humidity key comparison, EUROMET.T-K6 was successfully completed in year 2008. After this comparison, a new low dew-point generator was introduced at LPM in Croatia as a result of progress in the EUROMET P912 project. With this new facility, the LPM uncertainties decreased significantly and the operating range became significantly wider. Therefore, it was decided to arrange a bilateral comparison between LPM and MIKES in Finland providing a link to EUROMET.T-K6 and CCT-K6. This comparison was carried out in a manner similar to other K6 comparisons but only one transfer standard was used instead of two units and the measurement point -70 °C was added to the measurement scheme. At all measurement points, the bilateral equivalence was well within the estimated expanded uncertainty at the approximately 95% confidence level. Also, the deviations of the LPM results from the EUROMET.T-K6 reference values were smaller than their expanded uncertainties. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  15. Portable Dew Point Mass Spectrometry System for Real-Time Gas and Moisture Analysis

    Science.gov (United States)

    Arkin, C.; Gillespie, Stacey; Ratzel, Christopher

    2010-01-01

    A portable instrument incorporates both mass spectrometry and dew point measurement to provide real-time, quantitative gas measurements of helium, nitrogen, oxygen, argon, and carbon dioxide, along with real-time, quantitative moisture analysis. The Portable Dew Point Mass Spectrometry (PDP-MS) system comprises a single quadrupole mass spectrometer and a high vacuum system consisting of a turbopump and a diaphragm-backing pump. A capacitive membrane dew point sensor was placed upstream of the MS, but still within the pressure-flow control pneumatic region. Pressure-flow control was achieved with an upstream precision metering valve, a capacitance diaphragm gauge, and a downstream mass flow controller. User configurable LabVIEW software was developed to provide real-time concentration data for the MS, dew point monitor, and sample delivery system pressure control, pressure and flow monitoring, and recording. The system has been designed to include in situ, NIST-traceable calibration. Certain sample tubing retains sufficient water that even if the sample is dry, the sample tube will desorb water to an amount resulting in moisture concentration errors up to 500 ppm for as long as 10 minutes. It was determined that Bev-A-Line IV was the best sample line to use. As a result of this issue, it is prudent to add a high-level humidity sensor to PDP-MS so such events can be prevented in the future.

  16. Development of a neural fuzzy system for advanced prediction of dew point pressure in gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Nowroozi, Saeed; Hashemipour, Hasan; Schaffie, Mahin [Department of Chemical Engineering, Shahid Bahonar University of Kerman (Iran); ERC, Shahid Bahonar University of Kerman (Iran); Ranjbar, Mohammad [Department of Mining Engineering, Shahid Bahonar University of Kerman (Iran); ERC, Shahid Bahonar University of Kerman (Iran)

    2009-03-15

    Dew point pressure is one of the most critical quantities for characterizing a gas condensate reservoir. So, accurate determination of this property has been the main challenge in reservoir development and management. The experimental determination of dew point pressure in PVT cell is often difficult especially in case of lean retrograde gas condensate. Empirical correlations and some equations of state can be used to calculate reservoir fluid properties. Empirical correlations do not have ability to reliable duplicate the temperature behavior of constant composition fluids. Equations of state have convergence problem and need to be tuned against some experimental data. Complexity, non-linearity and vagueness are some reservoir parameter characteristic which can be propagated simply by intelligent system. With the advantage of fuzzy sets in knowledge representation and the high capacity of neural nets (NNs) in learning knowledge expressed in data, in this paper a neural fuzzy system(NFS) is proposed to predict dew point pressure of gas condensate reservoir. The model was developed using 110 measurements of dew point pressure. The performance of the model is compared against performance of some of the most accurate and general correlations for dew point pressure calculation. From the results of this study, it can be pointed out that this novel method is more accurate and reliable with the mean square error of 0.058%, 0.074% and 0.044% for training, validation and test processes, respectively. (author)

  17. On dew and micrometeorology in an arid coastal ecosystem

    NARCIS (Netherlands)

    Heusinkveld, B.G.

    2008-01-01

    This study investigated intriguing aspects of dew within a sandy arid ecosystem situated in the NW Negev desert, Israel. The goal was to quantify dew formation and evaporation processes through sensor design, field measurements and modelling. To do this, two new sensors were developed. The first

  18. Dew Measurements along a Longitudinal Sand Dune Transect

    NARCIS (Netherlands)

    Jacobs, A.F.G.; Heusinkveld, B.G.; Berkowicz, S.

    2000-01-01

    In a desert environment dew can serve as an important source of moisture for plants, biological crusts, insects and small animals. A measurement programme was carried out within a sand dune belt situated in the northwestern Negev desert, Israel, to measure daily amounts of dew deposition as well as

  19. Transport-induced shifts in condensate dew-point and composition in multicomponent systems with chemical reaction

    Science.gov (United States)

    Rosner, D. E.; Nagarajan, R.

    1985-01-01

    Partial heterogeneous condensation phenomena in multicomponent reacting systems are analyzed taking into consideration the chemical element transport phenomena. It is demonstrated that the dew-point surface temperature in chemically reactive systems is not a purely thermodynamic quantity, but is influenced by the multicomponent diffusion and Soret-mass diffusion phenomena. Several distinct dew-points are shown to exist in such systems and, as a result of transport constraints, the 'sharp' locus between two chemically distinct condensates is systematically moved to a difference mainstream composition.

  20. Estimation of precipitable water at different locations using surface dew-point

    Science.gov (United States)

    Abdel Wahab, M.; Sharif, T. A.

    1995-09-01

    The Reitan (1963) regression equation of the form ln w = a + bT d has been examined and tested to estimate precipitable water vapor content from the surface dew point temperature at different locations. The results of this study indicate that the slope b of the above equation has a constant value of 0.0681, while the intercept a changes rapidly with latitude. The use of the variable intercept technique can improve the estimated result by about 2%.

  1. Automatic dew-point hygrometer making use of US -ray backscattering and controlled at the constant amount of dew

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Shigeaki; Kobayashi, Hisanobu

    1988-08-01

    A control system which consists of proportional and integral control to maintain the constant amount of dew was developed in this hygrometer. The dew points were measured within an accuracy of +-1 deg C in the ranging from -4 to 32 deg C. The response time for suddenly changing humidity was about 8 min.

  2. Automated and continuously operating acid dew point measuring instrument for flue gases

    Energy Technology Data Exchange (ETDEWEB)

    Reckmann, D.; Naundorf, G.

    1986-06-01

    Design and operation is explained for a sulfuric acid dew point indicator for continuous flue gas temperature control. The indicator operated successfully in trial tests over several years with brown coal, gas and oil combustion in a measurement range of 60 to 180 C. The design is regarded as uncomplicated and easy to manufacture. Its operating principle is based on electric conductivity measurement on a surface on which sulfuric acid vapor has condensed. A ring electrode and a PtRh/Pt thermal element as central electrode are employed. A scheme of the equipment design is provided. Accuracy of the indicator was compared to manual dew point sondes manufactured by Degussa and showed a maximum deviation of 5 C. Manual cleaning after a number of weeks of operation is required. Fly ash with a high lime content increases dust buildup and requires more frequent cleaning cycles.

  3. Dew-point hygrometry system for measurement of evaporative water loss in infants.

    Science.gov (United States)

    Ariagno, R L; Glotzbach, S F; Baldwin, R B; Rector, D M; Bowley, S M; Moffat, R J

    1997-03-01

    Evaporation of water from the skin is an important mechanism in thermal homeostasis. Resistance hygrometry, in which the water vapor pressure gradient above the skin surface is calculated, has been the measurement method of choice in the majority of pediatric investigations. However, resistance hygrometry is influenced by changes in ambient conditions such as relative humidity, surface temperature, and convection currents. We have developed a ventilated capsule method that minimized these potential sources of measurement error and that allowed second-by-second, long-term, continuous measurements of evaporative water loss in sleeping infants. Air with a controlled reference humidity (dew-point temperature = 0 degree C) is delivered to a small, lightweight skin capsule and mixed with the vapor on the surface of the skin. The dew point of the resulting mixture is measured by using a chilled mirror dew-point hygrometer. The system indicates leaks, is mobile, and is accurate within 2%, as determined by gravimetric calibration. Examples from a recording of a 13-wk-old full-term infant obtained by using the system give evaporative water loss rates of approximately 0.02 mgH2O.cm-2.min-1 for normothermic baseline conditions and values up to 0.4 mgH2O.cm-2. min-1 when the subject was being warmed. The system is effective for clinical investigations that require dynamic measurements of water loss.

  4. Verification of alternative dew point hygrometer for CV-LRT in MONJU. Short- and long-term verification of capacitance-type dew point hygrometer (Translated document)

    International Nuclear Information System (INIS)

    Ichikawa, Shoichi; Chiba, Yusuke; Ono, Fumiyasu; Hatori, Masakazu; Kobayashi, Takanori; Uekura, Ryoichi; Hashiri, Nobuo; Inuzuka, Taisuke; Kitano, Hiroshi; Abe, Hisashi

    2017-03-01

    To reduce the influence of maintenance of dew point hygrometers on the plant schedule at the prototype fast-breeder reactor MONJU, Japan Atomic Energy Agency examined a capacitance-type dew point hygrometer as an alternative to the lithium-chloride dew point hygrometer being used in the containment vessel leak rate test. As verifications, a capacitance-type dew point hygrometer was compared with a lithium-chloride dew point hygrometer under a containment vessel leak rate test condition. And the capacitance-type dew point hygrometer was compared with a high-precision-mirror-surface dew point hygrometer for long-term (2 years) in the containment vessel as an unprecedented try. A comparison of a capacitance-type dew point hygrometer with a lithium-chloride dew point hygrometer in a containment vessel leak rate test (Atmosphere: nitrogen, Testing time: 24 h) revealed no significant difference between the capacitance-type dew point hygrometer and the lithium-chloride dew point hygrometer. A comparison of the capacitance-type dew point hygrometer with the high-precision-mirror-surface dew point hygrometer for long-term verification (Atmosphere: air, Testing time: 24 months) revealed that the capacitance-type dew point hygrometer satisfied the instrumental specification (synthesized precision of detector and converter: ±2.04°C) specified in the Leak Rate Test Regulations for Nuclear Reactor Containment Vessel. It was confirmed that the capacitance-type dew point hygrometer can be used as a long-term alternative to the lithium-chloride dew point hygrometer without affecting the dew point hygrometer maintenance schedule of the MONJU plant. (author)

  5. The New LMK Primary Standard for Dew-Point Sensor Calibration: Evaluation of the High-Range Saturator Efficiency

    Science.gov (United States)

    Hudoklin, Domen; Drnovšek, Janko

    2008-10-01

    In the field of hygrometry, a primary dew-point standard can be realized according to several proven principles, such as single-pressure (1-P), two-pressure (2-P), or divided flow. Different realizations have been introduced by various national laboratories, each resulting in a stand-alone complex generation system. Recent trends in generator design favor the single-pressure principle without recirculation because it promises theoretically lower uncertainty and because it avoids problems regarding the leak tightness of the recirculation. Instead of recirculation, the efficiency of saturation, the key factor, is increased by preconditioning the inlet gas entering the saturator. For preconditioning, a presaturator or purifier is used to bring the dew point of the inlet stream close to the saturator temperature. The purpose of the paper is to identify the minimum requirements for the preconditioning system and the main saturator to assure efficient saturation for the LMK generator. Moreover, the aim is also to find out if the preconditioning system can be avoided despite the rather simple construction of the main saturator. If this proves to be the case, the generator design can be simplified while maintaining an accurate value of the generated dew point. Experiments were carried out within the scope of improving our existing primary generator in the above-ambient dew-point range up to +70°C. These results show the generated dew point is within the measurement uncertainty for any dew-point value of the inlet gas. Thus, the preconditioning subsystem can be avoided, which leads to a simplified generator design.

  6. New methods of subcooled water recognition in dew point hygrometers

    Science.gov (United States)

    Weremczuk, Jerzy; Jachowicz, Ryszard

    2001-08-01

    Two new methods of sub-cooled water recognition in dew point hygrometers are presented in this paper. The first one- impedance method use a new semiconductor mirror in which the dew point detector, the thermometer and the heaters were integrated all together. The second one an optical method based on a multi-section optical detector is discussed in the report. Experimental results of both methods are shown. New types of dew pont hydrometers of ability to recognized sub-cooled water were proposed.

  7. Analysis of points of dew and contents of humidity of gassy mixtures N2-H2 O and CH4 H2 O

    International Nuclear Information System (INIS)

    Bedoya M, D; Muller, C; Oellrich, L R

    1995-01-01

    The actual knowledge of the exact water content in saturated gas mixtures still is incomplete, especially in the high pressure and low temperature region. Hence, dew point measurements with nitrogen - water and methane-water mixtures were performed; at pressures of 3 and 6 MPa and temperatures from 258 K to 288 K. The dew points were determined with the dew point mirror method and the water content by means of the Karl-Fischer-titration. The experimental values were compared to correlations from the literature. The approach by Sharma-Campbell resulted in the best description of the system nitrogen - water. For temperatures below 273 K the assumption of ideal behavior proved to be sufficient for the system methane-water, whereas for temperatures above 273 K calculations with the two-parameter corresponding states principle in combination with a fugacity correction turned out to be the best

  8. Technical aspects of acid dew point measurement in furnace exhaust. Messtechnik fuer die Saeuretaupunktmessung in Feuerungsabgasen

    Energy Technology Data Exchange (ETDEWEB)

    Struschka, M.; Baumbach, G.

    1986-01-01

    SO/sub 3/ formation in flue gases and the effect of furnace parameters, furnace type and design on the efficiency of SO/sub 2/ conversion were investigated in a detailed bibliographic study. Phase equilibrium data for the binary system H/sub 2/SO/sub 4//H/sub 2/O and equations for calculating the acid dew point are presented, and the available wet chemical methods for SO/sub 3/ concentration measurements in flue gases are reviewed. The SM1 acid dew point measuring instrument availabe at the authors' institute was modified by installing a new measuring probe, an external thermoelement intensifier, and a new PD control element for temperature control in the measuring surfaces. Acid dew point measurements were carried out in two different furnaces, i.e. a domestic boiler for light fuel oil and an industrial furnace fuelled with heavy oil at the Stuttgart University heat- and power plant. The measurements are compared with data from relevant publications. (orig./RB) With 80 figs., 7 tabs.

  9. Dew water effects on leaf water using a stable isotope approach

    Science.gov (United States)

    Kim, K.; Lee, X.

    2009-12-01

    The presence of dew is a common meteorological phenomenon in field conditions and takes into account for significant portion of hydrologic processes in terrestrial ecosystems. The isotope composition of leaf water plays an important role in the isotopic water and carbon fluxes between terrestrial plants and the atmosphere. However, the consequence of dew formation in the plant-atmosphere relations has been ignored in many studies. The objective of this study is to improve our understanding of environmental and biological controls on the leaf water in equilibrium with dew water through laboratory experiments. Five species of plants (soybean, corn, sorghum, wheat, cotton) were grown hydroponically with water of a known isotopic content in a greenhouse. On the day of the experiment, they were first moved to ambient environment in full sunlight for at least 6 hr and then into a dark container inside the lab for up to 48 hr in which water vapor isotope ratios, temperature, and humidity were controlled. This arrangement created a step change in the forcing on the plant isotopic exchange. Leaves were sampled prior to the transfer to the dark container and 6 more times every 4 - 12 hr over the experiment. Humidity inside the container was saturated to mimic dew events in field conditions. Water from the leaf samples was extracted by a vacuum line and was analyzed for both δD and δ18O. The dataset will allow us to evaluate leaf water isotopic theories by exploring the transitions of the isotopic ratio of leaf water in response to the step change. Specifically, we are interested in whether the stomatal opening is an effective pathway for gaseous exchange in total darkness and how the transitional behaviors of the isotopic ratio of leaf water differ between the C3 and C4 photosynthesis pathways.

  10. Bubble and Dew Point Calculations in Multicomponent and Multireactive Mixtures

    OpenAIRE

    Bonilla-Petriciolet, A.; Acosta-Martínez, A.; Bravo-Sánchez, U. I.; Segovia-Hernández, J. G.

    2006-01-01

    Bubble and dew point calculations are useful in chemical engineering and play an important role in the study of separation equipments for non-reactive and reactive mixtures. To the best of the authors’s knowledge, few methods have been proposed for these calculations in systems with several chemical reactions. The objective of this paper is to introduce new conditions for performing bubble and dew point calculations in reactive mixtures. We have developed these conditions based on the a...

  11. Environmental dew point and skin and lip weathering.

    Science.gov (United States)

    Devillers, C; Piérard, G E; Quatresooz, P; Piérard, S

    2010-05-01

    Xerosis represents a physiological response of the stratum corneum (SC) to environmental threats. The influence of the environmental dew point (DP) is not fully understood. This parameter is the air temperature at which the relative humidity is maximum. This study aimed to assess the relationship between the environmental DP and the water-holding capacity of the skin and lower lip vermilion. For comparison, SC property was evaluated after occlusive application of cooled and uncooled hydrogel pads. Electrometric measurements using a dermal phase meter (DPM) device were performed on the back of the hands, the cheeks and the lower lip of 40 healthy menopausal women. Assessments were performed in the outdoor conditions during winter and spring. The same measurements were recorded after hydrogel pads, at room temperature or cooled to 4 degrees C, were placed for 15 min on the test sites. The environmental DP was recorded at each evaluation time. The SC water-holding capacity was discretely influenced by the DP. In the open-air environmental conditions, a positive linear relationship was found on the cheeks between the DP and DPM values. The relationship was weaker on the lips. Conversely, a consistent increase in DPM values was recorded immediately after removal of the cooled and uncooled hydrogel pads. The observations made in the open-air testing conditions are consistent with the predicted events following the Arrhenius law. By contrast, the combination of cooling and occlusion by the hydrogel pads is responsible for the reverse effect on the SC.

  12. A thermal conductivity model for nanofluids including effect of the temperature-dependent interfacial layer

    International Nuclear Information System (INIS)

    Sitprasert, Chatcharin; Dechaumphai, Pramote; Juntasaro, Varangrat

    2009-01-01

    The interfacial layer of nanoparticles has been recently shown to have an effect on the thermal conductivity of nanofluids. There is, however, still no thermal conductivity model that includes the effects of temperature and nanoparticle size variations on the thickness and consequently on the thermal conductivity of the interfacial layer. In the present work, the stationary model developed by Leong et al. (J Nanopart Res 8:245-254, 2006) is initially modified to include the thermal dispersion effect due to the Brownian motion of nanoparticles. This model is called the 'Leong et al.'s dynamic model'. However, the Leong et al.'s dynamic model over-predicts the thermal conductivity of nanofluids in the case of the flowing fluid. This suggests that the enhancement in the thermal conductivity of the flowing nanofluids due to the increase in temperature does not come from the thermal dispersion effect. It is more likely that the enhancement in heat transfer of the flowing nanofluids comes from the temperature-dependent interfacial layer effect. Therefore, the Leong et al.'s stationary model is again modified to include the effect of temperature variation on the thermal conductivity of the interfacial layer for different sizes of nanoparticles. This present model is then evaluated and compared with the other thermal conductivity models for the turbulent convective heat transfer in nanofluids along a uniformly heated tube. The results show that the present model is more general than the other models in the sense that it can predict both the temperature and the volume fraction dependence of the thermal conductivity of nanofluids for both non-flowing and flowing fluids. Also, it is found to be more accurate than the other models due to the inclusion of the effect of the temperature-dependent interfacial layer. In conclusion, the present model can accurately predict the changes in thermal conductivity of nanofluids due to the changes in volume fraction and temperature for

  13. Validation of a dew-point generator for pressures up to 6 MPa using nitrogen and air

    Science.gov (United States)

    Bosma, R.; Mutter, D.; Peruzzi, A.

    2012-08-01

    A new primary humidity standard was developed at VSL that, in addition to ordinary operation with air and nitrogen at atmospheric pressure, can be operated with other carrier gases such as natural gas at pressures up to 6 MPa and SF6 at pressures up to 1 MPa. The temperature range of the standard is from -80 °C to +20 °C. In this paper, we report the validation of the new primary dew-point generator in the temperature range -41 °C to +5 °C and the pressure range 0.1 MPa to 6 MPa using nitrogen and air. For the validation the flow through the dew-point generator was varied up to 10 l min-1 (at 23 °C and 1013 hPa) and the dew point of the gas entering the generator was varied up to 15 °C above the dew point exiting the generator. The validation results showed that the new generator, over the tested temperature and pressure range, can be used with a standard uncertainty of 0.02 °C frost/dew point. The measurements used for the validation at -41 °C and -20 °C with nitrogen and at +5 °C with air were also used to calculate the enhancement factor at pressures up to 6 MPa. For +5 °C the differences between the measured and literature values were compatible with the respective uncertainties. For -41 °C and -20 °C they were compatible only up to 3 MPa. At 6 MPa a discrepancy was observed.

  14. Experimental study on dew point corrosion characteristics of the heating surface in a 65 t/h biomass-fired circulating fluidized bed boiler

    International Nuclear Information System (INIS)

    Wang, Yungang; Ma, Haidong; Liang, Zhiyuan; Chen, Heng; Zhao, Qinxin; Jin, Xin

    2016-01-01

    Highlights: • Dew point corrosion and ash deposit tests in a biomass-fired boiler were performed. • The XRD, XRF and SEM methods were used to analyze corrosion samples. • The deposits were made up of ash deposit layer, coupling layer and corrosion layer. • The metal matrix simultaneously confronted chlorine corrosion and oxygen corrosion. - Abstract: The dew point corrosion characteristics of the heating surface in a 65 t/h biomass-fired circulating fluidized bed (CFB) boiler were experimentally studied. The cross-sectional morphology and composition of the ash deposition were analyzed by scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray fluorescence spectrum (XRF), respectively. The results showed that the test tube surface was covered by ash deposit layer, coupling layer and corrosion layer. The ash deposit layer and the coupling layer were prone to spall off together. The coupling layer consists of partial ash and corrosion products. The corrosion layer was mainly composed of chlorides (FeCl_3, FeCl_2, and FeOCl) and oxides (FeOOH, Fe_2O_3). With the increase of the tube wall temperature, the corrosion depth decreased dramatically and the dew point corrosion was alleviated efficiently. The metal matrix simultaneously suffered from chlorine corrosion and oxygen corrosion. As the tube wall temperature was above water dew point, the main corrosion mode was oxygen corrosion. As the tube wall temperature was below water dew point, the main corrosion mode was chlorine corrosion.

  15. Bubble-point and dew-point equation for binary refrigerant mixture R22-R142b

    Energy Technology Data Exchange (ETDEWEB)

    Liancheng Tan; Zhongyou Zhao; Yonghong Duan (Xi' an Jiaotong Univ., Xi' an (China). Dept. of Power Machinery Engineering)

    1992-01-01

    A bubble-point and dew-point equation (in terms either of temperature or of pressure is suggested for the refrigerant mixture R22-R142b), which is regarded as one of the alternatives to R12. This equation has been examined with experimental data. A modified Rackett equation for the calculation of the bubble-point volume is also proposed. Compared with the experimental data, the rms errors in the calculated values of the bubble-point temperature, the dew-point temperature, and the bubble-point volume are 1.093%, 0.947%, and 1.120%, respectively. The calculation covers a wide range of temperatures and pressures, even near the critical point. It is shown how the equations are extrapolated to calculate other binary refrigerant mixtures. (author)

  16. Joining and fabrication techniques for high temperature structures including the first wall in fusion reactor

    International Nuclear Information System (INIS)

    Lee, Ho Jin; Lee, B. S.; Kim, K. B.

    2003-09-01

    The materials for PFC's (Plasma Facing Components) in a fusion reactor are severely irradiated with fusion products in facing the high temperature plasma during the operation. The refractory materials can be maintained their excellent properties in severe operating condition by lowering surface temperature by bonding them to the high thermal conducting materials of heat sink. Hence, the joining and bonding techniques between dissimilar materials is considered to be important in case of the fusion reactor or nuclear reactor which is operated at high temperature. The first wall in the fusion reactor is heated to approximately 1000 .deg. C and irradiated severely by the plasma. In ITER, beryllium is expected as the primary armour candidate for the PFC's; other candidates including W, Mo, SiC, B4C, C/C and Si 3 N 4 . Since the heat affected zones in the PFC's processed by conventional welding are reported to have embrittlement and degradation in the sever operation condition, both brazing and diffusion bonding are being considered as prime candidates for the joining technique. In this report, both the materials including ceramics and the fabrication techniques including joining technique between dissimilar materials for PFC's are described. The described joining technique between the refractory materials and the dissimilar materials may be applicable for the fusion reactor and Generation-4 future nuclear reactor which are operated at high temperature and high irradiation

  17. Joining and fabrication techniques for high temperature structures including the first wall in fusion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ho Jin; Lee, B. S.; Kim, K. B

    2003-09-01

    The materials for PFC's (Plasma Facing Components) in a fusion reactor are severely irradiated with fusion products in facing the high temperature plasma during the operation. The refractory materials can be maintained their excellent properties in severe operating condition by lowering surface temperature by bonding them to the high thermal conducting materials of heat sink. Hence, the joining and bonding techniques between dissimilar materials is considered to be important in case of the fusion reactor or nuclear reactor which is operated at high temperature. The first wall in the fusion reactor is heated to approximately 1000 .deg. C and irradiated severely by the plasma. In ITER, beryllium is expected as the primary armour candidate for the PFC's; other candidates including W, Mo, SiC, B4C, C/C and Si{sub 3}N{sub 4}. Since the heat affected zones in the PFC's processed by conventional welding are reported to have embrittlement and degradation in the sever operation condition, both brazing and diffusion bonding are being considered as prime candidates for the joining technique. In this report, both the materials including ceramics and the fabrication techniques including joining technique between dissimilar materials for PFC's are described. The described joining technique between the refractory materials and the dissimilar materials may be applicable for the fusion reactor and Generation-4 future nuclear reactor which are operated at high temperature and high irradiation.

  18. Measurement of dew droplets in initial deposition at dew point by using a phase-shift interference microscope

    Science.gov (United States)

    Matsumoto, Shigeaki; Toyooka, Satoru; Hoshino, Mitsuo

    2002-09-01

    In order to measure the total mass per unit area of dew droplets deposited on a metal plate in the dew-point hygrometer, the shape of a dew droplet deposited on a copper plate was measured accurately by using an interference microscope that employed a phase-shift technique. The microscope was constructed by adding a piezoelectric transducer to an usual interference microscope. A simple method that uses a conventional speaker horn and an optical fiber cable was introduced to depress speckle noise. The shape of a dew droplet deposited on the copper plate surface with 0.1 μm in average roughness was measured with an accuracy of +/-3nm. The mass of a dew droplet could be calculated numerically from the volume of its shape and was of the order of 10-9 g. The total mass of dew droplets deposited per unit area and the deposition velocity were obtained under a gentle wind. The total mass was the order of 10-5 g/cm2 at the beginning of deposition and the deposition velocity was ranged from 2x10-6 to 6x10-5 g/cm2.min.

  19. Study on dew point evaporative cooling system with counter-flow configuration

    International Nuclear Information System (INIS)

    Lin, J.; Thu, K.; Bui, T.D.; Wang, R.Z.; Ng, K.C.; Chua, K.J.

    2016-01-01

    Highlights: • Numerical model for a dew point evaporative cooler verified with experiments. • Saturation point of the working air is independent of the inlet air conditions. • The intensity of cooling capacity and water evaporation are studied. • The overall heat transfer coefficient for the working air is analyzed. • The conditions to achieve sub-wet bulb cooling are examined. - Abstract: Dew point evaporative cooling has great potential as a disruptive process for sensible cooling of air below its entering wet bulb temperature. This paper presents an improved mathematical model for a single-stage dew point evaporative cooler in a counter-flow configuration. Longitudinal heat conduction and mass diffusion of the air streams, channel plate and water film, as well as the temperature difference between the plate and water film, are accounted for in the model. Predictions of the product air temperature are validated using three sets of experimental data within a discrepancy of 4%. The cooler’s heat and mass transfer process is analyzed in terms of its cooling capacity intensity, water evaporation intensity, and overall heat transfer coefficient along the channel. Parametric studies are conducted at different geometric and operating conditions. For the conditions evaluated, the study reveals that (1) the saturation point of the working air occurs at a fixed point regardless of the inlet air conditions, and it is mainly influenced by the working air ratio and channel height; (2) the intensity of the water evaporation approaches a minimum at 0.2 to 0.3 m from the entrance; (3) the wet channel can be separated into two zones, and the overall heat transfer coefficient is above 100 W/(m"2·K) after the temperature of water film becomes higher than the working air temperature.

  20. A temperature dependent cyclic plasticity model for hot work tool steel including particle coarsening

    Science.gov (United States)

    Jilg, Andreas; Seifert, Thomas

    2018-05-01

    Hot work tools are subjected to complex thermal and mechanical loads during hot forming processes. Locally, the stresses can exceed the material's yield strength in highly loaded areas as e.g. in small radii in die cavities. To sustain the high loads, the hot forming tools are typically made of martensitic hot work steels. While temperatures for annealing of the tool steels usually lie in the range between 400 and 600 °C, the steels may experience even higher temperatures during hot forming, resulting in softening of the material due to coarsening of strengthening particles. In this paper, a temperature dependent cyclic plasticity model for the martensitic hot work tool steel 1.2367 (X38CrMoV5-3) is presented that includes softening due to particle coarsening and that can be applied in finite-element calculations to assess the effect of softening on the thermomechanical fatigue life of hot work tools. To this end, a kinetic model for the evolution of the mean size of secondary carbides based on Ostwald ripening is coupled with a cyclic plasticity model with kinematic hardening. Mechanism-based relations are developed to describe the dependency of the mechanical properties on carbide size and temperature. The material properties of the mechanical and kinetic model are determined on the basis of tempering hardness curves as well as monotonic and cyclic tests.

  1. Study on dew point evaporative cooling system with counter-flow configuration

    KAUST Repository

    Lin, J.

    2015-12-18

    Dew point evaporative cooling has great potential as a disruptive process for sensible cooling of air below its entering wet bulb temperature. This paper presents an improved mathematical model for a single-stage dew point evaporative cooler in a counter-flow configuration. Longitudinal heat conduction and mass diffusion of the air streams, channel plate and water film, as well as the temperature difference between the plate and water film, are accounted for in the model. Predictions of the product air temperature are validated using three sets of experimental data within a discrepancy of 4%. The cooler’s heat and mass transfer process is analyzed in terms of its cooling capacity intensity, water evaporation intensity, and overall heat transfer coefficient along the channel. Parametric studies are conducted at different geometric and operating conditions. For the conditions evaluated, the study reveals that (1) the saturation point of the working air occurs at a fixed point regardless of the inlet air conditions, and it is mainly influenced by the working air ratio and channel height; (2) the intensity of the water evaporation approaches a minimum at 0.2 to 0.3m from the entrance; (3) the wet channel can be separated into two zones, and the overall heat transfer coefficient is above 100W/(m2·K) after the temperature of water film becomes higher than the working air temperature.

  2. Modeling of the Direct Current Generator Including the Magnetic Saturation and Temperature Effects

    Directory of Open Access Journals (Sweden)

    Alfonso J. Mercado-Samur

    2013-11-01

    Full Text Available In this paper the inclusion of temperature effect on the field resistance on the direct current generator model DC1A, which is valid to stability studies is proposed. First, the linear generator model is presented, after the effect of magnetic saturation and the change in the resistance value due to temperature produced by the field current are included. The comparison of experimental results and model simulations to validate the model is used. A direct current generator model which is a better representation of the generator is obtained. Visual comparison between simulations and experimental results shows the success of the proposed model, because it presents the lowest error of the compared models. The accuracy of the proposed model is observed via Modified Normalized Sum of Squared Errors index equal to 3.8979%.

  3. MHD model including small-scale perturbations in a plasma with temperature variations

    International Nuclear Information System (INIS)

    Kuvshinov, B.N.; Mikhailovskii, A.B.

    1996-01-01

    The possibility is studied of using a hydrodynamic model to describe a magnetized plasma with density and temperature variations on scales that are arbitrary with respect to the ion Larmor radius. It is shown that the inertial component of the transverse ion thermal flux should be taken into account. This component is found from the collisionless kinetic equation. It can also be obtained from the equations of the Grad type. A set of two-dimensional hydrodynamic equations for ions is obtained with this component taken into account. These equations are used to derive model hydrodynamic expressions for the density and temperature variations. It is shown that, for large-scale perturbations (when the wavelengths are longer than the ion Larmor radius), the expressions derived coincide with the corresponding kinetic expressions and, for perturbations on sub-Larmor scales (when the wavelengths are shorter than the Larmor radius), they agree qualitatively. Hydrodynamic dispersion relations are derived for several types of drift waves with arbitrary wavenumbers. The range of applicability of the MHD model is determined from a comparison of these dispersion relations with the kinetic ones. It is noted that, on the basis of results obtained, drift effects can be included in numerical MHD codes for studying plasma instabilities in high-temperature regimes in tokamaks

  4. Dew point vs bubble point : a misunderstood constraint on gravity drainage processes

    Energy Technology Data Exchange (ETDEWEB)

    Nenninger, J. [N-Solv Corp., Calgary, AB (Canada); Gunnewiek, L. [Hatch Ltd., Mississauga, ON (Canada)

    2009-07-01

    This study demonstrated that gravity drainage processes that use blended fluids such as solvents have an inherently unstable material balance due to differences between dew point and bubble point compositions. The instability can lead to the accumulation of volatile components within the chamber, and impair mass and heat transfer processes. Case studies were used to demonstrate the large temperature gradients within the vapour chamber caused by temperature differences between the bubble point and dew point for blended fluids. A review of published data showed that many experiments on in-situ processes do not account for unstable material balances caused by a lack of steam trap control. A study of temperature profiles during steam assisted gravity drainage (SAGD) studies showed significant temperature depressions caused by methane accumulations at the outside perimeter of the steam chamber. It was demonstrated that the condensation of large volumes of purified solvents provided an efficient mechanism for the removal of methane from the chamber. It was concluded that gravity drainage processes can be optimized by using pure propane during the injection process. 22 refs., 1 tab., 18 figs.

  5. Calorific value and EnEV (German Energy Saving Ordinance). Why return flow temperatures are to be planned below the dew point; Brennwert und EnEV. Warum Ruecklauftemperaturen weit unter Taupunkt planen?

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2003-07-01

    Why does the efficiency of a condensing boiler system increase by 5 percent if the temperature is lowered from 45 to 30 degrees centigrade? The condensation temperature of 57-58 degrees centigrade is far higher, so the cold return flow should always remove the complete evaporation heat from the flue gas plumes and transfer it to the incoming flow. Why is this not the case?. [German] Wieso klettert der Wirkungsgrad einer Brennwertkesselanlage bei Absenkung der Kesselruecklauftemperatur von vorher 45 C auf zum Beispiel 30 C um beachtliche 5 Prozent an? Der Wasserdampftaupunkt des Abgases liegt mit 57 C oder 58 C doch in jedem Fall weit oberhalb der 45 C. Der kalte Ruecklauf muesste mithin in beiden Faellen den 58-graedigen Rauchgasschwaden die komplette Verdampfungswaerme entziehen und dem Vorlauf zufuehren - tut er aber nicht. Warum nicht? (orig.)

  6. New Primary Dew-Point Generators at HMI/FSB-LPM in the Range from -70 °C to +60 °C

    Science.gov (United States)

    Zvizdic, Davor; Heinonen, Martti; Sestan, Danijel

    2012-09-01

    To extend the dew-point range and to improve the uncertainties of the humidity scale realization at HMI/FSB-LPM, new primary low- and high-range dew-point generators were developed and implemented in cooperation with MIKES, in 2009 through EUROMET Project No. 912. The low-range saturator is designed for primary realization of the dew-point temperature scale from -70 °C to + 5 °C, while the high-range saturator covers the range from 1 °C to 60 °C. The system is designed as a single-pressure, single-pass dew-point generator. MIKES designed and constructed both the saturators to be implemented in dew-point calibration systems at LPM. The LPM took care of purchasing and adapting liquid baths, of implementing the temperature and pressure measurement equipment appropriate for use in the systems, and development of gas preparation and flow control systems as well as of the computer-based automated data acquisition. The principle and the design of the generator are described in detail and schematically depicted. The tests were performed at MIKES to investigate how close both the saturators are to an ideal saturator. Results of the tests show that both the saturators are efficient enough for a primary realization of the dew-point temperature scale from -70 °C to + 60 °C, in the specified flow-rate ranges. The estimated standard uncertainties due to the non-ideal saturation efficiency are between 0.02 °C and 0.05 °C.

  7. Numerical study of a novel dew point evaporative cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Riangvilaikul, B.; Kumar, S. [Energy Field of Study, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120 (Thailand)

    2010-11-15

    Dew point evaporative cooling system is an alternative to vapor compression air conditioning system for sensible cooling of ventilation air. This paper presents the theoretical performance of a novel dew point evaporative cooling system operating under various inlet air conditions (covering dry, moderate and humid climate) and influence of major operating parameters (namely, velocity, system dimension and the ratio of working air to intake air). A model of the dew point evaporative cooling system has been developed to simulate the heat and mass transfer processes. The outlet air conditions and system effectiveness predicted by the model using numerical method for known inlet parameters have been validated with experimental findings and with recent literature. The model was used to optimize the system parameters and to investigate the system effectiveness operating under various inlet air conditions. (author)

  8. Modeling of Temperature-Dependent Noise in Silicon Nanowire FETs including Self-Heating Effects

    Directory of Open Access Journals (Sweden)

    P. Anandan

    2014-01-01

    Full Text Available Silicon nanowires are leading the CMOS era towards the downsizing limit and its nature will be effectively suppress the short channel effects. Accurate modeling of thermal noise in nanowires is crucial for RF applications of nano-CMOS emerging technologies. In this work, a perfect temperature-dependent model for silicon nanowires including the self-heating effects has been derived and its effects on device parameters have been observed. The power spectral density as a function of thermal resistance shows significant improvement as the channel length decreases. The effects of thermal noise including self-heating of the device are explored. Moreover, significant reduction in noise with respect to channel thermal resistance, gate length, and biasing is analyzed.

  9. Investigation of Primary Dew-Point Saturator Efficiency in Two Different Thermal Environments

    Science.gov (United States)

    Zvizdic, D.; Heinonen, M.; Sestan, D.

    2015-08-01

    The aim of this paper is to describe the evaluation process of the performance of the low-range saturator (LRS), when exposed to two different thermal environments. The examined saturator was designed, built, and tested at MIKES (Centre for Metrology and Accreditation, Finland), and then transported to the Laboratory for Process Measurement (LPM) in Croatia, where it was implemented in a new dew-point calibration system. The saturator works on a single-pressure-single-pass generation principle in the dew/frost-point temperature range between and . The purpose of the various tests performed at MIKES was to examine the efficiency and non-ideality of the saturator. As a test bath facility in Croatia differs from the one used in Finland, the same tests were repeated at LPM, and the effects of different thermal conditions on saturator performance were examined. Thermometers, pressure gauges, an air preparation system, and water for filling the saturator at LPM were also different than those used at MIKES. Results obtained by both laboratories indicate that the efficiency of the examined saturator was not affected either by the thermal conditions under which it was tested or by equipment used for the tests. Both laboratories concluded that LRS is efficient enough for a primary realization of the dew/frost-point temperature scale in the range from to , with flow rates between and . It is also shown that a considerable difference of the pre-saturator efficiency, indicated by two laboratories, did not have influence to the overall performance of the saturator. The results of the research are presented in graphical and tabular forms. This paper also gives a brief description of the design and operation principle of the investigated low-range saturator.

  10. KEY COMPARISON: Final report of APMP.T-K6 (original name APMP-IC-1-97): Comparison of humidity measurements using a dew point meter as a transfer standard

    Science.gov (United States)

    Li, Wang; Takahashi, C.; Hussain, F.; Hong, Yi; Nham, H. S.; Chan, K. H.; Lee, L. T.; Chahine, K.

    2007-01-01

    This APMP key comparison of humidity measurements using a dew point meter as a transfer standard was carried out among eight national metrology institutes from February 1999 to January 2001. The NMC/SPRING, Singapore was the pilot laboratory and a chilled mirror dew point meter offered by NMIJ was used as a transfer standard. The transfer standard was calibrated by each participating institute against local humidity standards in terms of frost and dew point temperature. Each institute selected its frost/dew point temperature calibration points within the range from -70 °C to 20 °C frost/dew point with 5 °C step. The majority of participating institutes measured from -60 °C to 20 °C frost/dew point and a simple mean evaluation was performed in this range. The differences between the institute values and the simple means for all participating institutes are within two standard deviations from the mean values. Bilateral equivalence was analysed in terms of pair difference and single parameter Quantified Demonstrated Equivalence. The results are presented in the report. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  11. Application of a two-sinker densimeter for phase-equilibrium measurements: A new technique for the detection of dew points and measurements on the (methane + propane) system

    International Nuclear Information System (INIS)

    McLinden, Mark O.; Richter, Markus

    2016-01-01

    Highlights: • A new technique for detecting dew points in fluid mixtures is described. • The method makes use of a two-sinker densimeter. • The technique is based on a quantitative measurement of sample mass adsorbed onto the surface of the densimeter sinkers. • The dew-point density and dew-point pressure are determined with low uncertainty. • The method is applied to the (methane + propane) system and compared to traditional methods. - Abstract: We explore a novel method for determining the dew-point density and dew-point pressure of fluid mixtures and compare it to traditional methods. The (p, ρ, T, x) behavior of three (methane + propane) mixtures was investigated with a two-sinker magnetic suspension densimeter over the temperature range of (248.15–293.15) K; the measurements extended from low pressures into the two-phase region. The compositions of the gravimetrically prepared mixtures were (0.74977, 0.50688, and 0.26579) mole fraction methane. We analyzed isothermal data by: (1) a “traditional” analysis of the intersection of a virial fit of the (p vs. ρ) data in the single-phase region with a linear fit of the data in the two-phase region; and (2) an analysis of the adsorbed mass on the sinker surfaces. We compared these to a traditional isochoric experiment. We conclude that the “adsorbed mass” analysis of an isothermal experiment provides an accurate determination of the dew-point temperature, pressure, and density. However, a two-sinker densimeter is required.

  12. Dew point measurement technique utilizing fiber cut reflection

    Science.gov (United States)

    Kostritskii, S. M.; Dikevich, A. A.; Korkishko, Yu. N.; Fedorov, V. A.

    2009-05-01

    The fiber optical dew point hygrometer based on change of reflection coefficient for fiber cut has been developed and examined. We proposed and verified the model of condensation detector functioning principle. Experimental frost point measurements on air with different frost points have been performed.

  13. Evaluation of the dew point cooling technology; Beoordeling technologie dauwpuntskoeling

    Energy Technology Data Exchange (ETDEWEB)

    Bootsveld, N.R.; Afink, J. [TNO Milieu, Energie en Procesinnovatie TNO-MEP, Amersfoort (Netherlands); Uges, P.G.H. (ed.) [Standex Periodieken, Veenendaal (Netherlands)

    2003-01-01

    Results of measurements on an indirect adiabatic dew point cooling system are presented and discussed. The cooling system has been developed by ComfortAir, Raalte, Netherlands. [Dutch] De meetresultaten van door ComfortAir in samenwerking met TNO-MEP uitgevoerde metingen aan een indirect werkende adiabatische dauwpuntkoeler worden gepresenteerd en besproken.

  14. Accurate prediction of the dew points of acidic combustion gases by using an artificial neural network model

    International Nuclear Information System (INIS)

    ZareNezhad, Bahman; Aminian, Ali

    2011-01-01

    This paper presents a new approach based on using an artificial neural network (ANN) model for predicting the acid dew points of the combustion gases in process and power plants. The most important acidic combustion gases namely, SO 3 , SO 2 , NO 2 , HCl and HBr are considered in this investigation. Proposed Network is trained using the Levenberg-Marquardt back propagation algorithm and the hyperbolic tangent sigmoid activation function is applied to calculate the output values of the neurons of the hidden layer. According to the network's training, validation and testing results, a three layer neural network with nine neurons in the hidden layer is selected as the best architecture for accurate prediction of the acidic combustion gases dew points over wide ranges of acid and moisture concentrations. The proposed neural network model can have significant application in predicting the condensation temperatures of different acid gases to mitigate the corrosion problems in stacks, pollution control devices and energy recovery systems.

  15. Development of a Dew-Point Generator for Gases Other than Air and Nitrogen and Pressures up to 6 MPa

    Science.gov (United States)

    Bosma, R.; Peruzzi, A.

    2012-09-01

    A new primary humidity standard is currently being developed at VSL that, in addition to ordinary operation with air and nitrogen at atmospheric pressure, can be operated also with special carrier gases such as natural gas and SF6 and at pressures up to 6 MPa. In this paper, the design and construction of this new primary dew-point generator and the preliminary tests performed on the generator are reported. The results of the first efficiency tests, performed for the dew-point temperature range from -50 °C to 20°C, for pressures up to 0.7MPa and for carrier gas flow rates up to 4L· min-1, showed satisfactory generator performance when used in the single-pass mode, i.e., with no recirculation of the carrier gas.

  16. Dew Point Temperature Affects Ascospore Release of Allergenic Genus Leptosphaeria

    OpenAIRE

    Sadyś, M.; Kaczmarek, J.; Grinn-Gofron, A.; Rodinkova, V.; Prikhodko, A.; Bilous, E.; Strzelczak, A.; Herbert, Rob; Jedryczka, M.

    2018-01-01

    The genus Leptosphaeria contains numerous fungi that cause the symptoms of asthma and also parasitize wild and crop plants. In search of a robust and universal forecast model, the ascospore concentration in air was measured and weather data recorded from 1 March to 31 October between 2006 and 2012. The experiment was conducted in three European countries of the temperate climate, i.e., Ukraine, Poland, and the UK. Out of over 150 forecast models produced using artificial neural networks (ANNs...

  17. An automatic dew-point hygrometer making use of β-ray backscattering and controlled at the constant amount of dew

    International Nuclear Information System (INIS)

    Matsumoto, Shigeaki; Kobayashi, Hisanobu

    1988-01-01

    A control system which consists of proportional and integral control to maintain the constant amount of dew was developed in this hygrometer. The dew points were measured within an accuracy of ±1 deg C in the ranging from -4 to 32 deg C. The response time for suddenly changing humidity was about 8 min. (author)

  18. Correlation of dew- and bubble-point curves for binary refrigerant mixtures. [Correlation between dew-point pressure(saturated vapor state) and bubble-point pressure(saturated liquid state)]. Niseibunkei kongo reibai no roten oyobi futten kyokusen no sokan

    Energy Technology Data Exchange (ETDEWEB)

    Yada, N. (Kanagawa Institute of Technology, Kanagawa (Japan)); Watanabe, K. (Keio University, Tokyo (Japan). Faculty of Science and Technology)

    1991-12-25

    The paper makes a correlation expressing dew- and bubble-point curves using measured values for seven binary refrigerant freon-mixtures. In most binary systems at the same temperature, the pressure shows a different value between in a saturated vapor state (dew-point pressure) and in a saturated liquid state (bubble-point pressure). The target is such correlation as has as simple a function form as possible and is able to estimate even near the critical point where it used to be difficult to estimate. The pressure difference between measured values of the dew- and bubble-point pressure and values calculated from Raoult's law showing an ideal mixture of fluid is expressed by a simple function form of reduced temperature Tr and molar fraction. Tr is thermodynamic temperature/critical temperature. Reproducibility of this correlation is less than {plus minus}3% of the pressure deviation. Concerning also the arbitary composition range and near the critical point, the dew- and bubble-point pressure can be calculated accurately. 24 refs., 4 figs., 5 tabs.

  19. Measurement of evaporative water loss in small animals by dew-point hygrometry.

    Science.gov (United States)

    Bernstein, M H; Hudson, D M; Stearns, J M; Hoyt, R W

    1977-08-01

    This paper presents the procedures and equations to be utilized for measurement of evaporative water loss (mw), by use of the dew-point hygrometer, in small animals exposed to air containing water vapor in an open-flow system. The system accounted accurately for the water evaporated from a bubble flask. In addition, hygrometric measurements of pulmocutaneous mw in pigeons (Columba livia, mean mass 0.31 kg) agreed closely with simultaneous gravimetric measurements, utilizing a desiccant in the sample stream, in a manner independently of air temperature (Ta, 20 or 40 degrees C), ambient water vapor pressure (PW, 4-16 10(2) Pa), or mw (5-66 mg-min-1). Evaporation in pigeons was independent of PW at 20 degrees C, but increased with decreasing PW at 40 degrees C, suggesting differences in ventilatory adjustments to changes in PW at the two temperatures.

  20. Natural gas treatment: Simultaneous water and hydrocarbon-dew point-control

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, T. (Solvay Catalysts GmbH, Hannover (Germany)); Rennemann, D. (Solvay Catalysts GmbH, Hannover (Germany)); Schulz, T. (Solvay Catalysts GmbH, Hannover (Germany))

    1993-10-01

    Natural gas is a multicomponent mixture of hydrocarbons. The condensation behavior of such mixtures is different from single component systems. The so-called retrograde behavior leads to the observations that saturated vapor (dew point curve) and saturated liquid curve (bubble point curve) are not identical. Between both is a region of saturated phases which even can exist above the critical point. Following this behaviour it is possible that condensation might occur at pressure decrease or at temperature increase, respectively. This phenomenon is undesired in natural gas pipeline networks. Selective removal of higher hydrocarbons by the means of adsorption can change the phase behavior in such a way that condensation does not occur at temperatures and pressures specified for gas distribution. (orig.)

  1. Miniaturised Optical Fibre Sensor for Dew Detection Inside Organ Pipes

    Directory of Open Access Journals (Sweden)

    Francesco Baldini

    2008-01-01

    Full Text Available A new optical sensor for the continuous monitoring of the dew formation inside organ pipes was designed. This aspect is particularly critical for the conservation of organs in unheated churches since the dew formation or the condensation on the pipe surfaces can contribute to many kinds of physical and chemical disruptive mechanisms. The working principle is based on the change in the reflectivity which is observed on the surface of the fibre tip, when a water layer is formed on its distal end. Intensity changes of the order of 35% were measured, following the formation of the water layer on the distal end of a 400/430 μm optical fibre. Long-term tests carried out placing the fibre tip inside the base of an in-house-made metallic foot of an organ pipe located in an external environment revealed the consistency of the proposed system.

  2. Determination of dew absorption by coffee plant through deuterium concentrations in leaf water

    Energy Technology Data Exchange (ETDEWEB)

    Leopoldo, P R [Faculdade de Ciencias Medicas e Biologicas de Botucatu (Brazil); Salati, E; Matsui, E [Centro de Energia Nuclear na Agricultura, Piracicaba (Brazil)

    1975-12-01

    The effect of dew falling on leaves on the water metabolism of the coffee plant (Coffea arabica) is examined. The use of natural stable isotopes variations in plant physiological studies is demonstrated. Water extracted from leaf samples is analysed by mass spectrometry. Analyses of deuterium concentrations in water extracted from plant leaves, dew and nutrient solutions are made. Determination of changes in deuterium concentration in the water of leaves from plants exposed to dew, compared with leaves not exposed to dew, is carried out. Results show that during daytime there is an enrichment in deuterium in water contained in the leaves, while at night the opposite occurs.

  3. Initial response of an automatic dew-point hygrometer using [beta]-ray backscattering

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Shigeaki (Saitama Univ., Urawa (Japan). Faculty of Engineering)

    1992-05-01

    This paper describes the initial response of an automatic dew-point hygrometer using [beta]-ray backscattering. The response time after starting of measurement was evaluated in which the dew point measured with the hygrometer reached a value of 90 percent of the correct dew point in its response. Theoretical calculation was made by means of the loop transfer function of a control system employed in the hygrometer. The response times ranged from 1.7 min to 16 min corresponding to the dew point of 47.5degC and -6degC, respectively, and agreed well with experimental ones. (author).

  4. Determination of dew absorption by coffee plant through deuterium concentrations in leaf water

    International Nuclear Information System (INIS)

    Leopoldo, P.R.; Salati, E.; Matsui, E.

    1975-01-01

    The effect of dew falling on leaves on the water metabolism of the coffee plant (Coffea arabica) is examined. The use of natural stable isotopes variations in plant physiological studies is demonstrated. Water extracted from leaf samples is analysed by mass spectrometry. Analyses of deuterium concentrations in water extracted from plant leaves, dew and nutrient solutions are made. Determination of changes in deuterium concentration in the water of leaves from plants exposed to dew, compared with leaves not exposed to dew, is carried out. Results show that during daytime there is an enrichment in deuterium in water contained in the leaves, while at night the opposite occurs [pt

  5. Dew as an Adaptation Measure to Meet Agricultural and Reforestation Water Demand in a Changing Climate

    Science.gov (United States)

    Tomaszkiewicz, Marlene; Abou Najm, Majdi; Alameddine, Ibrahim; El Fadel, Mutasem

    2014-05-01

    Dew harvesting, believed to be an ancient technique, has recently re-emerged as a viable and sustainable water resource. Nightly yields are relatively low, yet non-negligible, and dew events occur more frequently than rainfall promoting its effectiveness, particularly in arid and semi-arid regions. In this study, we demonstrate how dew can be harvested and subsequently used for small-scale irrigation to meet agricultural and reforestation water demand. Polyethylene dew harvesting systems were constructed and placed in the field. Dew was harvested as a result of the radiative cooling during the night, thus allowing dew formation under conditions of high humidity. Condensed dew formed upon the planar surface was collected by gravity. Water demand for selected crops and trees within a pilot study area (Lebanon) was estimated using a deficit irrigation model. Simulations of water demand requirements of various plants and surfaces were performed and compared to dew volumes to assess the ability of the system to meet all or in part the plant water demands across seasons. Data from the polyethylene low-cost dew condensers have shown that within the pilot study, average nightly dew yields were 0.1 L m-2 of condensing surface with a maximum yield of 0.4 L m-2. Dew events occurred generally more frequently than precipitation events, with an estimated 40% of nights producing dew condensate. This translates to 50 mm of equivalent rainfall on average (during dew nights), with a maximum of 200 mm in one night, if one assumes using drip irrigation over a seedling within a 20 cm2 area. Using a simple deficit irrigation model, it was demonstrated that crops such as the tomato plant, which typically has a growing season during the dry summer, can potentially be irrigated solely by dew, thus eliminating the need for traditional irrigation sources. Similarly, young tree seedlings, such as the cedar tree, can depend upon dew as a primary water resource. Moreover, based on similar

  6. DEWS (DEep White matter hyperintensity Segmentation framework): A fully automated pipeline for detecting small deep white matter hyperintensities in migraineurs.

    Science.gov (United States)

    Park, Bo-Yong; Lee, Mi Ji; Lee, Seung-Hak; Cha, Jihoon; Chung, Chin-Sang; Kim, Sung Tae; Park, Hyunjin

    2018-01-01

    Migraineurs show an increased load of white matter hyperintensities (WMHs) and more rapid deep WMH progression. Previous methods for WMH segmentation have limited efficacy to detect small deep WMHs. We developed a new fully automated detection pipeline, DEWS (DEep White matter hyperintensity Segmentation framework), for small and superficially-located deep WMHs. A total of 148 non-elderly subjects with migraine were included in this study. The pipeline consists of three components: 1) white matter (WM) extraction, 2) WMH detection, and 3) false positive reduction. In WM extraction, we adjusted the WM mask to re-assign misclassified WMHs back to WM using many sequential low-level image processing steps. In WMH detection, the potential WMH clusters were detected using an intensity based threshold and region growing approach. For false positive reduction, the detected WMH clusters were classified into final WMHs and non-WMHs using the random forest (RF) classifier. Size, texture, and multi-scale deep features were used to train the RF classifier. DEWS successfully detected small deep WMHs with a high positive predictive value (PPV) of 0.98 and true positive rate (TPR) of 0.70 in the training and test sets. Similar performance of PPV (0.96) and TPR (0.68) was attained in the validation set. DEWS showed a superior performance in comparison with other methods. Our proposed pipeline is freely available online to help the research community in quantifying deep WMHs in non-elderly adults.

  7. Use of dew-point detection for quantitative measurement of sweating rate

    Science.gov (United States)

    Brengelmann, G. L.; Mckeag, M.; Rowell, L. B.

    1975-01-01

    A method of measuring sweat rate (SR) based on detection of dew point (DP) is proposed which has advantages that may be attractive to other laboratories concerned with recording SR from selected areas of skin. It is similar to other methods in that dry gas is passed through a capsule which isolates several square centimeters of skin surface. The difference is in the means of determining how much gaseous water is carried off in the effluent moist gas. The DP detector used is free of the drawbacks of previous devices. DP is obtained through the fundamental technique of determining the temperature at which condensate forms on a mirror. Variations in DP are tracked rapidly, and accurately (+ or - 0.8 C nominal, sensitivity + or - 0.05 C) over a wide range ( -40 C to +50 C) without measurable hysteresis. The detector asembly is rugged and readily opened for cleaning and inspection.

  8. Determination of dew point in natural gas; Determinacion del punto de rocio en el gas natural

    Energy Technology Data Exchange (ETDEWEB)

    Avila Calzada, S.; Marco Martinez, G.; Montenegro Soto, S. [ENAGAS (Spain)

    1995-07-01

    The natural gas can contain water and heavy hydrocarbons very dangerous for the equipments and the pipes. This is the reason of the importance of dew point. The value of this dew point is fixed in the supply contract conditions. This article studies the different evaluation methods, pointing out the advantages and disadvantages (Author)

  9. Detection of Dew-Point by substantial Raman Band Frequency Jumps (A new Method)

    DEFF Research Database (Denmark)

    Hansen, Susanne Brunsgaard; Berg, Rolf W.; Stenby, Erling Halfdan

    Detection of Dew-Point by substantial Raman Band Frequency Jumps (A new Method). See poster at http://www.kemi.dtu.dk/~ajo/rolf/jumps.pdf......Detection of Dew-Point by substantial Raman Band Frequency Jumps (A new Method). See poster at http://www.kemi.dtu.dk/~ajo/rolf/jumps.pdf...

  10. Effect of artificially-generated wind on removing guttation and dew ...

    African Journals Online (AJOL)

    DynabookSS

    2015-03-25

    Mar 25, 2015 ... wind on the formation and removal of guttation and dew droplets on rice leaves. ... Wind is thought to reduce the number of spores attached to rice plant and to promote removal of dew droplets on the leaves. Thus, the penetration of blast into ..... and the application for forecasting method of the rice blast.

  11. Estimating dew formation in rice, using seasonally averaged diel patterns of weather variables

    NARCIS (Netherlands)

    Luo, W.; Goudriaan, J.

    2004-01-01

    If dew formation cannot be measured it has to be estimated. Available simulation models for estimating dew formation require hourly weather data as input. However, such data are not available for places without an automatic weather station. In such cases the diel pattern of weather variables might

  12. Wireless sensor network-based greenhouse environment monitoring and automatic control system for dew condensation prevention.

    Science.gov (United States)

    Park, Dae-Heon; Park, Jang-Woo

    2011-01-01

    Dew condensation on the leaf surface of greenhouse crops can promote diseases caused by fungus and bacteria, affecting the growth of the crops. In this paper, we present a WSN (Wireless Sensor Network)-based automatic monitoring system to prevent dew condensation in a greenhouse environment. The system is composed of sensor nodes for collecting data, base nodes for processing collected data, relay nodes for driving devices for adjusting the environment inside greenhouse and an environment server for data storage and processing. Using the Barenbrug formula for calculating the dew point on the leaves, this system is realized to prevent dew condensation phenomena on the crop's surface acting as an important element for prevention of diseases infections. We also constructed a physical model resembling the typical greenhouse in order to verify the performance of our system with regard to dew condensation control.

  13. Wireless Sensor Network-Based Greenhouse Environment Monitoring and Automatic Control System for Dew Condensation Prevention

    Science.gov (United States)

    Park, Dae-Heon; Park, Jang-Woo

    2011-01-01

    Dew condensation on the leaf surface of greenhouse crops can promote diseases caused by fungus and bacteria, affecting the growth of the crops. In this paper, we present a WSN (Wireless Sensor Network)-based automatic monitoring system to prevent dew condensation in a greenhouse environment. The system is composed of sensor nodes for collecting data, base nodes for processing collected data, relay nodes for driving devices for adjusting the environment inside greenhouse and an environment server for data storage and processing. Using the Barenbrug formula for calculating the dew point on the leaves, this system is realized to prevent dew condensation phenomena on the crop’s surface acting as an important element for prevention of diseases infections. We also constructed a physical model resembling the typical greenhouse in order to verify the performance of our system with regard to dew condensation control. PMID:22163813

  14. Dew formation and activity of biological crusts

    NARCIS (Netherlands)

    Veste, M.; Heusinkveld, B.G.; Berkowicz, S.M.; Breckle, S.W.; Littmann, T.; Jacobs, A.F.G.

    2008-01-01

    Biological soil crusts are prominent in many drylands and can be found in diverse parts of the globe including the Atacama desert, Chile, the Namib desert, Namibia, the Succulent-Karoo desert, South Africa, and the Negev desert, Israel. Because precipitation can be negligible in deserts ¿ the

  15. Summaries of reports of the 30. Conference on low-temperature physics. Pt. 1. Fundamental questions of superconductivity including HTSC

    International Nuclear Information System (INIS)

    1994-01-01

    Thesis of reporsts of the 30th Conference on low-temperature physics are presented. Fundamental problems of superconductivity are discussed including HTSC in bulk crystals, in thin films of Josephson junctions, ceramics and heterostructures. Specific features of superconductor structure and magnetic properties and also different mechanisms of superconductivity are analyzed

  16. Development of sulfuric acid dew point corrosion resistant stainless steel for smokestacks and its ducts. Entotsu endoyo tairyusan roten fushoku stainless ko no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Sato, E.; Matsuhashi, R.; Koseki, T. (Nippon Steel Corp., Tokyo (Japan)); Ebara, R.; Nakamoto, H. (Mitsubishi Heavy Industries, Ltd., Tokyo (Japan))

    1993-05-20

    A new corrosion resistant steel was developed as a metal system lining material to prevent sulfuric acid dew point corrosion in smokestacks and ducts. SO3 in stack gas turns to sulfuric acid as a result of reacting with coexistent moisture in non-steady conditions during boiler actuation and shutdown when smokestack walls have low temperatures. When sulfuric acid thus generated contacts with metallic materials at temperatures lower than the sulfuric acid dew point temperature, sulfuric acid dew point corrosion occurs. During boiler steady operation, localized corrosion develops at clearance between salt deposits and the metallic materials. In order to improve the corrosion resistance, Mo, Cu and N were added in a reasonable range of amount. Entire surface corrosion resistance and local corrosion resistance were experimented in aqueous solutions simulating the smokestack environments to derive relational formulas with steel compositions. The new corrosion resistant steel met the the entire surface and local corrosion resistance requirements and was found economical. Low torsional velocity tensile and U-bend tests proved the steel satisfying the stress corrosion resistance requirement. Semi-automatic CO2 welding and shielded are welding provided good workability with no cracking, and impact strength and corrosion resistance in joints equivalent to those in the base material. 3 refs., 4 figs., 4 tabs.

  17. Effects of Engineered Wettability on the Efficiency of Dew Collection.

    Science.gov (United States)

    Gerasopoulos, Konstantinos; Luedeman, William L; Ölçeroglu, Emre; McCarthy, Matthew; Benkoski, Jason J

    2018-01-31

    Surface wettability plays an important role in dew collection. Nucleation is faster on hydrophilic surfaces, while droplets slide more readily on hydrophobic surfaces. Plants and animals in coastal desert environments appear to overcome this trade-off through biphilic surfaces with patterned wettability. In this study, we investigate the effects of millimeter-scale wettability patterns, mimicking those of the Stenocara beetle, on the rate of water collection from humid air. The rate of water collection per unit area is measured as a function of subcooling (ΔT = 1, 7, and 27 °C) and angle of inclination (from 10° to 90°). It is then compared for superbiphilic, hydrophilic, hydrophobic, and surperhydrophobic surfaces. For large subcooling, neither wettability nor tilt angle has a significant effect because the rate of condensation is so great. For 1 °C subcooling and large angles, hydrophilic surfaces perform best because condensation is the rate-limiting step. For low angles of inclination, superhydrophobic samples are best because droplet sliding is the rate-limiting step. Superbiphilic surfaces, in contrast to their superior fog collecting capabilities, generally collected dew at the slowest rate due to their inherent contact angle hysteresis. Theoretical considerations suggest that this finding may apply more generally to surfaces with patterned wettability.

  18. TFOS DEWS II Management and Therapy Report.

    Science.gov (United States)

    Jones, Lyndon; Downie, Laura E; Korb, Donald; Benitez-Del-Castillo, Jose M; Dana, Reza; Deng, Sophie X; Dong, Pham N; Geerling, Gerd; Hida, Richard Yudi; Liu, Yang; Seo, Kyoung Yul; Tauber, Joseph; Wakamatsu, Tais H; Xu, Jianjiang; Wolffsohn, James S; Craig, Jennifer P

    2017-07-01

    The members of the Management and Therapy Subcommittee undertook an evidence-based review of current dry eye therapies and management options. Management options reviewed in detail included treatments for tear insufficiency and lid abnormalities, as well as anti-inflammatory medications, surgical approaches, dietary modifications, environmental considerations and complementary therapies. Following this extensive review it became clear that many of the treatments available for the management of dry eye disease lack the necessary Level 1 evidence to support their recommendation, often due to a lack of appropriate masking, randomization or controls and in some cases due to issues with selection bias or inadequate sample size. Reflecting on all available evidence, a staged management algorithm was derived that presents a step-wise approach to implementing the various management and therapeutic options according to disease severity. While this exercise indicated that differentiating between aqueous-deficient and evaporative dry eye disease was critical in selecting the most appropriate management strategy, it also highlighted challenges, based on the limited evidence currently available, in predicting relative benefits of specific management options, in managing the two dry eye disease subtypes. Further evidence is required to support the introduction, and continued use, of many of the treatment options currently available to manage dry eye disease, as well as to inform appropriate treatment starting points and understand treatment specificity in relation to dry eye disease subtype. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Reprises textuelles dans The Dew Breaker d’Edwidge Danticat Rewriting / Reprising in Edwidge Danticat’s The Dew Breaker

    Directory of Open Access Journals (Sweden)

    Corinne Duboin

    2007-01-01

    Full Text Available In her recent novel, The Dew Breaker (2004, Haitian-American writer Edwidge Danticat weaves together the lives of her bruised Haitian characters and their torturer, a former Tonton Macoute, all in exile in the US. Seven of the nine chapters were previously published as separate short stories and have been rearranged to form a novel. The reader is then led to unravel a narrative tangle made of many threads. The disparate nature of the book, its non-linear narrative, the plurality of stories and voices, the gaps in a fragmented, elliptic text all bear witness to an alternative approach to creative writing. Like a seamstress, the novelist pieces together individual stories, connecting them as the multifarious facets of a great whole. In the wake of francophone Haitian writers (namely Jacques Roumain, the author of Masters of the Dew, and Jacques Stephen Alexis who wrote General Sun, My Brother, Edwidge Danticat fictionalizes the traumatic history of a people confronted with violence and terror and engages in a complex intertextual game. Combining ethics and aesthetics, temporal and textual memory, the novelist explores facts and, rather than giving answers, raises difficult questions. Her characters, whether victims or perpetrators, all strive to free themselves from a haunting past: is it ever possible to forgive so as to heal the pain? Can one make amends for the harm that has been done to victims who seek redress?

  20. The dew point response of the annulus gas system of Bruce NGS A

    International Nuclear Information System (INIS)

    Kenchington, J.; Ellis, P.J.; Meranda, D.

    1983-01-01

    The dew point response of the Annulus Gas System in Bruce A, Units 1 and 2 has been modelled in order to alert the operator of the presence of heavy water and to estimate the leak rate into the annulus. The computer model can be easily adapted to determine the Annulus Gas System dew point response in any station. It models the complex arrangement of the system and the transportation of moisture through the annuli by a combination of plug flow and mixing of CO 2 and D 2 O vapor. It predicts the response of the dew point monitor for a range of specified leak rates and positions of a leaking channel in a string of channels. This model has been used to calculate the variation of dew point and rate of change of dew point with respect to time (t). It shows that there is a maximum in the rate of dew point change (dT/dt) with respect to the corresponding dew point (T). This maximum is unique for a given leak rate and channel position. It is independent of the starting time for the leak. The computer programme has been verified by an analytical solution for the model

  1. Calculating the flue gas dew point for raw brown coal fired steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Schinkel, W.

    1977-01-01

    The paper analyzes parameters influencing the sulfuric acid dew point in flue gas of steam generators. Sulfur content and alkaline earths content in the fuel air ratio during combustion, fly ash content in the flue gas (which absorbs sulfur dioxide and sulfur trioxide) and combustion conditions in steam generators are relevant parameters in the combustion process. A thermodynamic and reaction kinetic calculation of the sulfuric acid dew point is, however, not yet possible. A statistical evaluation of dew point measurements in steam generators is, therefore, employed. Various diagrams show results of dew point measurements carried out at generators with steam capacities ranging from 40 to 660 t/h, which demonstrate relations of these parameters to flue gas dew points, in particular the relative sulfur content (sulfur content in the raw brown coal compared to coal ash content and alkaline earths content). A function is derived for the conversion of fuel sulfur to sulfur trioxide. A diagram presents the relation of the flue gas dew point to partial pressures of sulfuric acid and steam. Direct calculation of the flue gas dew point was achieved by the proposed method. It is applied in steam generator design. (17 refs.)

  2. Sales gas hydrocarbon dew point control with a refrigeration plant; Konditionierung des Kohlenwasserstofftaupunktes im Verkaufsgas mittels einer Kaelteanlage

    Energy Technology Data Exchange (ETDEWEB)

    Konieczny, J.; Scsepka, H. [OMV Aktiengesellschaft, Exploration and Production, Gaenserndorf (Austria)

    2004-11-01

    A new refrigeration plant was put on stream in the gas plant Aderklaa, Austria in the fall 2003. The quality criteria inherent to hydrocarbon dew point of the sales gas have already been accomplished. The contract (Allgemeinen Netzzugangsbedingungen) defines the hydrocarbon dew point at the value of 0 C with a pressure ranging 0-70 bar(g). Process facilities are a gas/gas-heat exchanger and a low-temperature-separator flanged to the chiller. A propane cycle produces the required cooling energy. The propane cycle consists of two propane compressors, one of them as back up, a condenser, an accumulator and an evaporator. About 50,000 m{sup 3} (V{sub n}) sales gas per hour are produced at a working pressure of 65 bar(g). Process gas coming from the sweetening plant Aderklaa I is lowered to a temperature of -14 C, where approx. 250 litres liquid hydrocarbons per hour are separated and saved. When the refrigeration plant was designed, attention was given to the operating costs to keep them low. This could be achieved by maximising surface area for heat transfer in the gas/gas-heat exchanger. After commissioning and start-up, full operability of the new plant was tested and documented. The pre-set project goals were accomplished, with respect to both the technical point of view and the economic aspects. (orig.)

  3. Technology assessment of dew point cooling; Beoordeling technologie dauwpuntskoeling

    Energy Technology Data Exchange (ETDEWEB)

    Uges, P.G.H. [Koudetechnisch Centrum, Nijmegen (Netherlands); Reinder, T.M.

    2003-03-01

    Results of measurements on an indirect adiabatic dew point cooling system are presented and discussed. The cooling system has been developed by OxyCom (formerly ComfortAir), Raalte, Netherlands. [Dutch] De techniek van dauwpuntskoeling is gebaseerd op bet principe van indirecte verdamping van water in een secundair circuit, waarbij geen extra vocht aan de te koelen luchtstroom wordt toegevoegd en waarmee luchttemperaturen worden bereikt die net boven het dauwpunt liggen en dus onder de natteboltemperatuur. Dauwpuntskoeling is een technische ontwikkeling met goede toekomstverwachtingen. Voorzover bekend zijn er tot op heden geen meetgegevens gepubliceerd met een dergelijke indirect werkende koeler. Dit artikel geeft de meetresultaten weer van een door OxyCorn in samenwerking met TNO-MEP uitgevoerd meetprogramma. Dit artikel is gebaseerd op de TNO-MEP rapportage met als auteurs N.R. Bootsveld en J. Afink en heeft eerder in het blad Koude en Luchtbehandeling, januari 2003, gestaan.

  4. Dew point of gases with low sulfuric acid content

    Energy Technology Data Exchange (ETDEWEB)

    Fieg, J.

    1981-07-01

    Discusses control of air pollution caused by sulfur compounds in solid fuels during combustion. Excessive amount of oxygen during combustion leads to formation of sulfur trioxide. Sulfur trioxide reacts with water vapor and forms sulfuric acid. Chemical reactions which lead to formation of sulfuric acid are described. Conditions for sulfuric acid condensation are analyzed. Several methods for determining dew point of flue gases with low sulfuric acid content are reviewed: methods based on determination of electric conductivity of condensed sulfuric acid (Francis, Cheney, Kiyoure), method based on determination of sulfuric acid concentration in the gaseous phase and in the liquid phase after cooling (Lee, Lisle and Sensenbaugh, Ross and Goksoyr). (26 refs.) (In Polish)

  5. A dew point signaller for conservation of works of art.

    Science.gov (United States)

    Camuffo, D; Valcher, S

    1986-03-01

    All works of art, from paintings, frescoes, sculptures, to monuments and buildings, are affected by diurnal and seasonal variations of the local microclimate, which induce interactions with the environmental atmosphere. Heat and vapour exchanges cause fluxes of heat and mass between the surface and the atmosphere, and may favour the agressivity of environmental pollutants. Condensation-evaporation cycles are recognized as being very important processes which adversely affect the life-time of the work of art. The need to control the microclimate or to stop condensation processes has been resolved by means of a dew-point signaller especially designed to overcome this problem. This paper discusses the characteristics of this device as well as the environmental philosophy which should be followed when conserving works of art.

  6. Characterization of Bacterial and Fungal Community Dynamics by High-Throughput Sequencing (HTS Metabarcoding during Flax Dew-Retting

    Directory of Open Access Journals (Sweden)

    Christophe Djemiel

    2017-10-01

    Full Text Available Flax dew-retting is a key step in the industrial extraction of fibers from flax stems and is dependent upon the production of a battery of hydrolytic enzymes produced by micro-organisms during this process. To explore the diversity and dynamics of bacterial and fungal communities involved in this process we applied a high-throughput sequencing (HTS DNA metabarcoding approach (16S rRNA/ITS region, Illumina Miseq on plant and soil samples obtained over a period of 7 weeks in July and August 2014. Twenty-three bacterial and six fungal phyla were identified in soil samples and 11 bacterial and four fungal phyla in plant samples. Dominant phyla were Proteobacteria, Bacteroidetes, Actinobacteria, and Firmicutes (bacteria and Ascomycota, Basidiomycota, and Zygomycota (fungi all of which have been previously associated with flax dew-retting except for Bacteroidetes and Basidiomycota that were identified for the first time. Rare phyla also identified for the first time in this process included Acidobacteria, CKC4, Chlorobi, Fibrobacteres, Gemmatimonadetes, Nitrospirae and TM6 (bacteria, and Chytridiomycota (fungi. No differences in microbial communities and colonization dynamics were observed between early and standard flax harvests. In contrast, the common agricultural practice of swath turning affects both bacterial and fungal community membership and structure in straw samples and may contribute to a more uniform retting. Prediction of community function using PICRUSt indicated the presence of a large collection of potential bacterial enzymes capable of hydrolyzing backbones and side-chains of cell wall polysaccharides. Assignment of functional guild (functional group using FUNGuild software highlighted a change from parasitic to saprophytic trophic modes in fungi during retting. This work provides the first exhaustive description of the microbial communities involved in flax dew-retting and will provide a valuable benchmark in future studies aiming

  7. Memory persistency and nonlinearity in daily mean dew point across India

    Science.gov (United States)

    Ray, Rajdeep; Khondekar, Mofazzal Hossain; Ghosh, Koushik; Bhattacharjee, Anup Kumar

    2016-04-01

    Enterprising endeavour has been taken in this work to realize and estimate the persistence in memory of the daily mean dew point time series obtained from seven different weather stations viz. Kolkata, Chennai (Madras), New Delhi, Mumbai (Bombay), Bhopal, Agartala and Ahmedabad representing different geographical zones in India. Hurst exponent values reveal an anti-persistent behaviour of these dew point series. To affirm the Hurst exponent values, five different scaling methods have been used and the corresponding results are compared to synthesize a finer and reliable conclusion out of it. The present analysis also bespeaks that the variation in daily mean dew point is governed by a non-stationary process with stationary increments. The delay vector variance (DVV) method has been exploited to investigate nonlinearity, and the present calculation confirms the presence of deterministic nonlinear profile in the daily mean dew point time series of the seven stations.

  8. Feedback dew-point sensor utilizing optimally cut plastic optical fibres

    Science.gov (United States)

    Hadjiloucas, S.; Irvine, J.; Keating, D. A.

    2000-01-01

    A plastic optical fibre reflectance sensor that makes full use of the critical angle of the fibres is implemented to monitor dew formation on a Peltier-cooled reflector surface. The optical configuration permits isolation of optoelectronic components from the sensing head and better light coupling between the reflector and the detecting fibre, giving a better signal of the onset of dew formation on the reflector. Continuous monitoring of the rate of change in reflectance as well as the absolute reflectance signals, the use of a novel polymethyl-methacrylate-coated hydrophobic film reflector on the Peltier element and the application of feedback around the point of dew formation, further reduces the possibility of contamination of the sensor head. Under closed-loop operation, the sensor is capable of cycling around the point of dew formation at a frequency of 2.5 Hz.

  9. Dew point of combustion products of coal from the Berezovo deposit

    Energy Technology Data Exchange (ETDEWEB)

    Petrov, V.A. (UralVTI (USSR))

    1990-11-01

    Evaluates properties of brown coal from the Berezovo deposit, Kansk-Achinsk basin, and properties of its combustion products. Coal properties are the following: sulfur content from 0.26 to 0.49%, ash content from 3.49 to 6.58%, moisture content from 31.6 to 36.9%, calorific value from 14,200 to 15,840 kJ/kg. Dew point of the combustion products amounts to 51 C and is equal to that of water vapor present in flue gases. Changing boiler output does not influence dew point. Increase in the excess air coefficient from 1.2 to 1.4 results in an increase in dew point by 2-3 K; further increase in air excess coefficient to 1.64 causes a decline in dew point by 3-4 K. 2 refs.

  10. Investigation of a novel dew point indirect evaporative air conditioning system for buildings

    OpenAIRE

    Duan, Zhiyin

    2011-01-01

    This study aims to improve the performance of existing indirect evaporative coolers. A new dew point indirect evaporative cooler with counter-current heat/mass exchanger was developed in this research by optimal design, material selection, numerical simulation, experimental investigations and economic, environmental, regional acceptance analysis. A new dew point heat/mass exchanger using a counter-current flow pattern was designed by numerical simulation in terms of material, structure, g...

  11. DINEOF reconstruction of clouded images including error maps – application to the Sea-Surface Temperature around Corsican Island

    Directory of Open Access Journals (Sweden)

    J.-M. Beckers

    2006-01-01

    Full Text Available We present an extension to the Data INterpolating Empirical Orthogonal Functions (DINEOF technique which allows not only to fill in clouded images but also to provide an estimation of the error covariance of the reconstruction. This additional information is obtained by an analogy with optimal interpolation. It is shown that the error fields can be obtained with a clever rearrangement of calculations at a cost comparable to that of the interpolation itself. The method is presented on the reconstruction of sea-surface temperature in the Ligurian Sea and around the Corsican Island (Mediterranean Sea, including the calculation of inter-annual variability of average surface values and their expected errors. The application shows that the error fields are not only able to reflect the data-coverage structure but also the covariances of the physical fields.

  12. Flooding During Drought: Learning from Stakeholder Engagement & Partner Coordination in the California-Nevada Drought Early Warning System (DEWS)

    Science.gov (United States)

    Sheffield, A. M.

    2017-12-01

    After more than 5 years of drought, extreme precipitation brought drought relief in California and Nevada and presents an opportunity to reflect upon lessons learned while planning for the future. NOAA's National Integrated Drought Information System (NIDIS) California-Nevada Drought Early Warning System (DEWS) in June 2017 convened a regional coordination workshop to provide a forum to discuss and build upon past drought efforts in the region and increase coordination, collaboration and information sharing across the region as a whole. Participants included federal, tribal, state, academic, and local partners who provided a post-mortem on the recent drought and impacts as well as recent innovations in drought monitoring, forecasts, and decision support tools in response to the historic drought. This presentation will highlight lessons learned from stakeholder outreach and engagement around flooding during drought, and pathways for moving forward coordination and collaboration in the region. Additional focus will be on the potential opportunities from examining California decision making calendars from this drought. Identified gaps and challenges will also be shared, such as the need to connect observations with social impacts, capacity building around available tools and resources, and future drought monitoring needs. Drought will continue to impact California and Nevada, and the CA-NV DEWS works to make climate and drought science readily available, easily understandable and usable for decision makers; and to improve the capacity of stakeholders to better monitor, forecast, plan for and cope with the impacts of drought.

  13. Development of manufacturing of low dew-point mixed gas of butane-air

    Energy Technology Data Exchange (ETDEWEB)

    Komine, Hitoshi

    1988-09-10

    A dehumidifying plant was installed to supply high-quality dehumidified butane-air mixed gas aiming at saving the heat required for vaporizing liquid butane by the heat exchange with the potential heat of air as well as the dehumidification of the air used for the mixed gas by cooling with the vaporizing latent heat of liquid butane. The plant has been smoothly operated since August, 1987. Butane sent from the air-dehumidifier is completely vaporized by hot water in the vaporizer and the vaporized butane ejected by the Venturi mixer to mix with the dehumidified air. The gas production capacity is 3000Nm/sup 3//h and the treating capacities of butane and air are 661 and 2339 Nm/sup 3//h, respectively. The dew point of the mixed gas is 18/sup 0/C under 0.7kg/cm/sup 2/G at atmospheric temperature of 38/sup 0/C subject to the operation of the plant only in hot and humid summer. It was demonstrated that the plant is characterized by low construction and operating costs, low level of noise and stable heat value of the product gas. (5 figs, 4 tabs, 1 photo)

  14. Parametric analysis of a combined dew point evaporative-vapour compression based air conditioning system

    Directory of Open Access Journals (Sweden)

    Shailendra Singh Chauhan

    2016-09-01

    Full Text Available A dew point evaporative-vapour compression based combined air conditioning system for providing good human comfort conditions at a low cost has been proposed in this paper. The proposed system has been parametrically analysed for a wide range of ambient temperatures and specific humidity under some reasonable assumptions. The proposed system has also been compared from the conventional vapour compression air conditioner on the basis of cooling load on the cooling coil working on 100% fresh air assumption. The saving of cooling load on the coil was found to be maximum with a value of 60.93% at 46 °C and 6 g/kg specific humidity, while it was negative for very high humidity of ambient air, which indicates that proposed system is applicable for dry and moderate humid conditions but not for very humid conditions. The system is working well with an average net monthly power saving of 192.31 kW h for hot and dry conditions and 124.38 kW h for hot and moderate humid conditions. Therefore it could be a better alternative for dry and moderate humid climate with a payback period of 7.2 years.

  15. Exploitation of humid air latent heat by means of solar assisted heat pumps operating below the dew point

    International Nuclear Information System (INIS)

    Scarpa, Federico; Tagliafico, Luca A.

    2016-01-01

    Highlights: • The opportunity of humid air latent heat exploitation by DX-SAHP is investigated. • A set of experimental tests confirms this opportunity and quantifies it as relevant. • A parametric analysis is performed, via simulation, to deepen the subject. • The energy gain is relevant during both night and daytime. - Abstract: Nowadays, the exploitation of environmental exergy resources for heating purposes (solar energy, convection heat transfer from ambient air, moist air humidity condensation) by means of properly designed heat pump systems is a possible opportunity. In particular, the use of direct expansion solar assisted heat pumps (DX-SAHP) is investigated in this study, when a bare external plate (the solar collector) is kept at temperatures lower than the dew point temperature of ambient air, so that condensation takes place on it. The potential of this technology is settled and an instrumented prototype of a small DX-SAHP system is used to verify the actual performance of the system, in terms of specific thermal energy delivered to the user, efficiency and regulation capabilities. Results clearly show that the contribution of the condensation is significant (20%–30% of the total harvested energy) overnight or in cloudy days with very low or no solar irradiation, and must be taken into account in a system model devoted to describe the DX-SAHP behavior. During daytime, the percentage gain decreases but is still consistent. By investigating along these lines, the heat due to condensation harvested by the collector is found to be a function of the dew-point temperature alone.

  16. Using dew points to estimate savings during a planned cooling shutdown

    Science.gov (United States)

    Friedlein, Matthew T.; Changnon, David; Musselman, Eric; Zielinski, Jeff

    2005-12-01

    In an effort to save money during the summer of 2003, Northern Illinois University (NIU) administrators instituted a four-day working week and stopped air conditioning buildings for the three-day weekends (Friday through Sunday). Shutting down the air conditioning systems caused a noticeable drop in electricity usage for that part of the campus that features in our study, with estimated total electricity savings of 1,268,492 kilowatt-hours or 17% of the average usage during that eight-week period. NIU's air conditioning systems, which relied on evaporative cooling to function, were sensitive to dew point levels. Greatest savings during the shutdown period occurred on days with higher dew points. An examination of the regional dew point climatology (1959 2003) indicated that the average summer daily dew point for 2003 was 14.9°C (58.8°F), which fell in the lowest 20% of the distribution. Based on the relationship between daily average dew points and electrical usage, a predictive model that could estimate electrical daily savings was created. This model suggests that electrical savings related to any future three-day shutdowns over summer could be much greater in more humid summers. Studies like this demonstrate the potential value of applying climatological information and of integrating this information into practical decision-making.

  17. Conditions for lowering the flue gas temperature; Foerutsaettning foer saenkning av roekgastemperatur

    Energy Technology Data Exchange (ETDEWEB)

    Nordling, Magnus

    2012-02-15

    In heat and power production, the efficiency of the power plant increases the larger share of heat from the flue gas that is converted to power. However, this also implies that the temperature of the heat exchanging surfaces is lowered. If the temperature is lowered to a temperature below the dew point of the flue gas, this would result in condensation of the gas, which in turn elevates the risk of serious corrosion attack on the surfaces where condensation occurs. Thus, it is important to determine the dew point temperature. One way of determining the dew point temperature is to use data on composition of the fuel together with operation parameters of the plant, thus calculating the dew point temperature. However, this calculation of the dew point is not so reliable, especially if hygroscopic salts are present. Therefore, for safety reasons, the temperature of the flue gas is kept well above the dew point temperature. This results in lowered over-all efficiency of the plant. It could also be expected that for a certain plant, some construction materials under certain operation conditions would have corrosion characteristics that may allow condensation on the surface without severe and unpredictable corrosion attack. However, by only using operation parameters and fuel composition, it is even harder to predict the composition of the condensate at different operation temperatures than to calculate the dew point temperature. If the dew point temperature was known with a greater certainty, the temperature of the flue gas could be kept lower, just above the estimated value of the dew point, without any increased risk for condensation. If, in addition, also the resulting composition of the condensate at different temperatures below the dew point is known, it can be predicted if the construction materials of the flue gas channel were compatible with the formed condensate. If they are compatible, the flue gas temperature can be further lowered from the dew point

  18. Chemical Characterization of Dew Water Collected in Different Geographic Regions of Poland

    Directory of Open Access Journals (Sweden)

    Jacek Namieśnik

    2008-06-01

    Full Text Available The results of a dew monitoring program performed in Poland with the aim to outline the chemical composition of dew water in meteorological context are presented. Dew samples were collected from eight measurement stations from August 2004 to November 2006. Taking into account the type of land use and characteristics of pollutant emission, sampling sites were divided into the following categories: rural, coastal urban and inland urban stations. Selected anions and cations as well as formaldehyde and sum of phenols were determined. The average TIC (Total Inorganic Ionic Content values in dew samples ranged from 0.83 to 3.93 between individual stations with 10.9 meq/L as the highest daily value of TIC measured. The average TIC values observed in dew at all stations were at a similar level (2.46 meq/L when compared with hoarfrost (2.86 meq/L. However, these values were much higher in comparison with other kinds of atmospheric water like precipitation (wet only; 0.37 meq/L or fog/cloud (1.01 meq/L. The pH values of dew water ranged from 5.22 to 7.35 for urban coastal stations, from 5.67 to 8.02 for urban inland stations and from 4.16 to 8.76 for dew samples collected in the rural area. HCHO was found in 97 % of dew samples, with concentrations ranging from 0.010 to 5.40 meq/L. Excluding stations near the seashore, where the contribution of Na+ and Cl- increased, the most important ions were sulphates. A very low contribution of NO3- and noticeable increase of Ca2+ which were not observed in the case of precipitation and fog water, were typical in all stations. The contribution of ammonium ion was two times higher at rural stations as a result of agricultural ammonia emissions. The strongest correlations were noticed between the sum of acidifying anions SO42- + NO3- and Ca2+ ion for all urban and rural stations. A very strong correlation was also observed for Na+ and Cl- ions in urban coastal stations, as a natural consequence of the location of these

  19. The influence of dew point during annealing on the power loss of electrical steel sheets

    Energy Technology Data Exchange (ETDEWEB)

    Broddefalk, Arvid [Development and Market Research, Cogent Power Ltd., P.O. Box 201, SE-735 23 Surahammar (Sweden)], E-mail: arvid.broddefalk@sura.se; Jenkins, Keith [Development and Market Research, Cogent Power Ltd., P.O. Box 201, SE-735 23 Surahammar (Sweden); Silk, Nick [Corus RD and T, Swinden Technology Centre, Moorgate Rotherham S60 3AR (United Kingdom); Lindenmo, Magnus [Development and Market Research, Cogent Power Ltd., P.O. Box 201, SE-735 23 Surahammar (Sweden)

    2008-10-15

    Decarburization is a necessary part of the processing of electrical steels if their carbon content is above a certain level. The process is usually carried out in a wet hydrogen-nitrogen atmosphere. Having a high dew point has a negative influence on the power loss, though. This is due to oxidation of the steel, which hinders domain wall motion near the surface. In this study, an increase of the power loss was only observed at a fairly high dew point (>20 deg. C). It was also only at these high dew points where a subsurface oxide layer was observed. The surfaces of samples with and without this layer were etched in steps. The magnetic properties of the etched samples corresponded well with the expected behavior based on GDOES profiles of the samples.

  20. The influence of dew point during annealing on the power loss of electrical steel sheets

    Science.gov (United States)

    Broddefalk, Arvid; Jenkins, Keith; Silk, Nick; Lindenmo, Magnus

    Decarburization is a necessary part of the processing of electrical steels if their carbon content is above a certain level. The process is usually carried out in a wet hydrogen-nitrogen atmosphere. Having a high dew point has a negative influence on the power loss, though. This is due to oxidation of the steel, which hinders domain wall motion near the surface. In this study, an increase of the power loss was only observed at a fairly high dew point (>20 °C). It was also only at these high dew points where a subsurface oxide layer was observed. The surfaces of samples with and without this layer were etched in steps. The magnetic properties of the etched samples corresponded well with the expected behavior based on GDOES profiles of the samples.

  1. Simultaneous measurements of formaldehyde and nitrous acid in dews and gas phase in the atmosphere of Santiago, Chile

    Science.gov (United States)

    Rubio, María A.; Lissi, Eduardo; Villena, Guillermo; Elshorbany, Y. F.; Kleffmann, Jörg; Kurtenbach, Ralf; Wiesen, Peter

    2009-12-01

    The amounts of formaldehyde and nitrous acid (HONO) in gas phase and dews of Santiago de Chile were simultaneously measured. Formaldehyde concentrations values in the liquid phase (dews) correlate fairly well with those in the gaseous phase and are even higher than those expected from gas-dew equilibrium. On the other hand, nitrite concentrations in dews were considerably smaller (ca. 15 times) than those expected from the gas-phase concentrations. This under-saturation is attributed to diffusion limitations due to the relatively large HONO solubility. In agreement with this, under-saturation increases with the rate of dew formation and the pH of the collected waters, factors that should increase the rate of gas to liquid HONO transfer required to reach equilibrium.

  2. High Response Dew Point Measurement System for a Supersonic Wind Tunnel

    Science.gov (United States)

    Blumenthal, Philip Z.

    1996-01-01

    A new high response on-line measurement system has been developed to continuously display and record the air stream dew point in the NASA Lewis 10 x 10 supersonic wind tunnel. Previous instruments suffered from such problems as very slow response, erratic readings, and high susceptibility to contamination. The system operates over the entire pressure level range of the 10 x 10 SWT, from less than 2 psia to 45 psia, without the need for a vacuum pump to provide sample flow. The system speeds up tunnel testing, provides large savings in tunnel power costs and provides the dew point input for the data-reduction subroutines which calculate test section conditions.

  3. Mechanisms of corrosion, falling short of dew point and formation of corrosion in boilers and exhaust systems. Mechanismen der Korrosionsbildung, der Taupunktunterschreitung und Entstehung von Korrosionen in Kessel- und Abgassystemen

    Energy Technology Data Exchange (ETDEWEB)

    Marx, E.

    1994-09-01

    In order to save energy boilers for heating systems are run on increasingly lower exhaust gas- and boiler temperatures. Combustion as such depends of type of fuel, boiler and burner design, design of exhaust systems and atmospheric disturbance variables. This article looks at the influence which these factors have on corrosion. Falling short of the dew point is an important parameter in this context. Possibilities of avoiding corrosion are explained. (BWI)

  4. A re-entrant resonator for the measurement of phase boundaries: dew points for {0.4026CH4 + 0.5974C3H8}

    International Nuclear Information System (INIS)

    Kandil, Mohamed E.; Marsh, Kenneth N.; Goodwin, Anthony R.H.

    2005-01-01

    For a natural gas and, especially, retrograde condensates, it is important for exploration and production that the (liquid + gas) phase boundary be known along with the ratio of liquid-to-gas volumes within the (liquid + gas) two-phase region. These fluid properties can be measured by a plethora of methods and here we report a method based on the measurement of the resonance frequency of the lowest order inductive-capacitance mode of a re-entrant cavity capable of operating at temperatures up to 473 K and pressures below 20 MPa. This instrument has been used to measure, at T 4 + 0.5974C 3 H 8 }. The measured dew pressures differ by less than 0.5 % from values obtained by interpolation of those reported in the literature, which were determined from measurements with experimental techniques that suffer from quite different potential sources of systematic error than the radio-frequency resonator used here. Dew pressures estimated from both NIST 14 and the Peng-Robinson equation of state lie within <±1 % of our results at temperature between (315 and 337) K while predictions obtained from the Soave Redlich Kwong cubic equation of state deviate from our results by 0.4 % at T = 315 K and these absolute differences increase smoothly with increasing temperature to be -2.4 % at T = 337 K

  5. A technical basis to relax the dew point specification for the environment in the vapor space in DWPF canisters

    International Nuclear Information System (INIS)

    Louthan, M.R. Jr.

    1995-05-01

    This memorandum establishes the technical basis to conclude that relaxing, from 0 C to 20 C, the dew point specification for the atmosphere in the vapor space (free volume) of a DWPF canister will not provide an environment that will cause significant amounts of corrosion induced degradation of the canister wall. The conclusion is based on engineering analysis, experience and review of the corrosion literature. The basic assumptions underlying the conclusion are: (1) the canister was fabricated from Type 304L stainless steel; (2) the corrosion behavior of the canister material, including base metal, fusion zones and heat effected zones, is typified by literature data for, and industrial experience with, 300 series austenitic stainless steels; and (3) the glass-metal crevices created during the pouring operation will not alter the basic corrosion resistance of the steel although such crevices might serve as sites for the initiation of minor amounts of corrosion on the canister wall

  6. Dew point effect of cooled hydrogel pads on human stratum corneum biosurface.

    Science.gov (United States)

    Xhauflaire-Uhoda, Emmanuelle; Paquet, Philippe; Piérard, Gérald E

    2008-01-01

    Cooled hydrogel pads are used to prevent overheating effects of laser therapy. They do not induce cold injuries to the skin, but their more subtle physiological effects have not been thoroughly studied. To describe the changes in transepidermal water loss and electrometric properties of the skin surface following application of cooled hydrogel pads. Measurements were performed on normal forearm skin of 27 healthy volunteers and on freshly excised skin from abdominoplasty. LaserAid hydrogel pads cooled to 4 degrees C were placed for 15 min on the forearm skin. Measurements of transepidermal water loss (TEWL) and electrometric properties (Corneometer, Nova DPM 900) were performed before application and after removal of the cooled pads. A consistent increase in corneometer units, dermal phase meter (DPM) values and TEWL were recorded at removal of the cooled hydrogel pads. Both the in vivo and in vitro assessments brought similar information. The similar changes disclosed in vitro and in vivo suggest that a common physical process is operating in these conditions. The observed phenomenon is opposite to the predicted events given by the Arrhenius law probably because of the combination of cooling and occlusion by the pads. A dew point effect (air temperature at which relative humidity is maximal) is likely involved in the moisture content of the stratum corneum. Thus, the biological impact of using cooling hydrogel pads during laser therapy is different from the effect of a cryogenic spray cooling procedure. The better preservation of the water balance in the stratum corneum by the cooled hydrogel pads could have a beneficial esthetic effect on laser treated areas. (c) 2008 S. Karger AG, Basel.

  7. Influence of Gas Atmosphere Dew Point on the Galvannealing of CMnSi TRIP Steel

    Science.gov (United States)

    Cho, Lawrence; Kim, Myung Soo; Kim, Young Ha; De Cooman, Bruno C.

    2013-11-01

    The Fe-Zn reaction occurring during the galvannealing of a Si-bearing transformation-induced plasticity (TRIP) steel was investigated by field-emission electron probe microanalysis and field-emission transmission electron microscopy. The galvannealing was simulated after hot dipping in a Zn bath containing 0.13 mass pct Al at 733 K (460 °C). The galvannealing temperature was in the range of 813 K to 843 K (540 °C to 570 °C). The kinetics and mechanism of the galvannealing reaction were strongly influenced by the gas atmosphere dew point (DP). After the galvannealing of a panel annealed in a N2+10 pct H2 gas atmosphere with low DPs [213 K and 243 K (-60 °C and -30 °C)], the coating layer consisted of δ (FeZn10) and η (Zn) phase crystals. The Mn-Si compound oxides formed during intercritical annealing were present mostly at the steel/coating interface after the galvannealing. Galvannealing of a panel annealed in higher DP [263 K and 273 K, and 278 K (-10 °C, 0 °C, and +5 °C)] gas atmospheres resulted in a coating layer consisting of δ and Г (Fe3Zn10) phase crystals, and a thin layer of Г 1 (Fe11Zn40) phase crystals at the steel/coating interface. The Mn-Si oxides were distributed homogeneously throughout the galvannealed (GA) coating layer. When the surface oxide layer thickness on panels annealed in a high DP gas atmosphere was reduced, the Fe content at the GA coating surface increased. Annealing in a higher DP gas atmosphere improved the coating quality of the GA panels because a thinner layer of oxides was formed. A high DP atmosphere can therefore significantly contribute to the suppression of Zn-alloy coating defects on CMnSi TRIP steel processed in hot dip galvanizing lines.

  8. 2D Numerical Modelling of the Resin Injection Pultrusion Process Including Experimental Resin Kinetics and Temperature Validation

    DEFF Research Database (Denmark)

    Rasmussen, Filip Salling; Sonne, Mads Rostgaard; Larsen, Martin

    In the present study, a two-dimensional (2D) transient Eulerian thermo-chemical analysis of a carbon fibre epoxy thermosetting Resin Injection Pultrusion (RIP) process is carried out. The numerical model is implemented using the well known unconditionally stable Alternating Direction Implicit (ADI......) scheme. The total heat of reaction and the cure kinetics of the epoxy thermosetting are determined using Differential Scanning Calorimetry (DSC). A very good agreement is observed between the fitted cure kinetic model and the experimental measurements. The numerical steady state temperature predictions...

  9. Dew point fast measurement in organic vapor mixtures using quartz resonant sensor

    Science.gov (United States)

    Nie, Jing; Liu, Jia; Meng, Xiaofeng

    2017-01-01

    A fast dew point sensor has been developed for organic vapor mixtures by using the quartz crystal with sensitive circuits. The sensor consists of the quartz crystal and a cooler device. Proactive approach is taken to produce condensation on the surface of the quartz crystal, and it will lead to a change in electrical features of the quartz crystal. The cessation of oscillation was measured because this phenomenon is caused by dew condensation. Such a phenomenon can be used to detect the dew point. This method exploits the high sensitivity of the quartz crystal but without frequency measurement and also retains the stability of the resonant circuit. It is strongly anti-interfered. Its performance was evaluated with acetone-methanol mixtures under different pressures. The results were compared with the dew points predicted from the universal quasi-chemical equation to evaluate the performance of the proposed sensor. Though the maximum deviations of the sensor are less than 1.1 °C, it still has a fast response time with a recovery time of less than 10 s, providing an excellent dehumidifying performance.

  10. An automated microlysimeter to study dew formation and evaporation in arid and semiarid regions

    NARCIS (Netherlands)

    Heusinkveld, B.G.; Berkowicz, S.M.; Jacobs, A.F.G.; Holtslag, A.A.M.; Hillen, W.C.A.M.

    2006-01-01

    The development of a simple and low-cost portable weighing microlysimeter that makes use of a load cell for automated recording and for studying daily dew formation, rate of accumulation, and subsequent evaporation in arid or semiarid regions during rainless seasons is presented. The sampling cup is

  11. Large Dew water collectors in a village of S-Morocco (Idouasskssou)

    Science.gov (United States)

    Lekouch, I.; Clus, O.; Durand, M.; Lanfourmi, M.; Muselli, M.; Milimouk, I.; Beysens, D.

    2010-07-01

    With precipitations close to 227 mm/year in average, the coastal region of south Morocco presents a chronically shortage of drinkable and fresh water. Since 1994, in the Mirleft area (150 km south of Agadir), inhabitants are facing a critically drought event. In the year 2007, only 49 mm of rain was recorded. However, measurements in Mirleft in the same year, showed that the dew yield was on order of 40 % of rain fall. In order to show to the local population the interest of recovering dew water in addition to rain water, a small nearby village (Idouasskssou, 8 km SE of Mirleft) was equipped with three pilot condensers of 136 m2 total surface area. In order to ensure a good integration of the project by the village inhabitants, a local organization (Association IMRJANE) collaborated to the project. A concrete tank at ground level with a flat horizontal surface, easily accessible for inhabitants and also a model for traditional Morocco terrace roofings, has been equipped with two lines of condensers (40.6 m²). All roofing materials were from local shops. Only the special radiative and hydrophilic coating was coming from non local resources (see www.opur.fr). The top of a second tank (aside the first one) was renovated and covered with a 21.2 m² two slopes steel roof, insulated and painted with the special dew coating as above. These roofs represent a condensation surface comparable to that of a very little house. A third condenser, with 73.8 m² surface area, was implemented directly on the ground, ensuring minimal work and very cheap implementation costs. Dew was collected and measured in one of the concrete tanks. The water production during 6 months, from 15-12-2008 to 31-07-2009 (137 dew events, 47 % of days) was more than 3800 L (more than 0.2 mm/dew day). It is important to note that, while the devices are specifically designed to condense dew water, they also harvest rain and fog as well, thus providing to the population a valuable water resource.

  12. The contact-temperature ignition (CTI) criteria for propagating chemical reactions including the effect of moisture and application to Hanford waste

    International Nuclear Information System (INIS)

    Cash, R.J.

    1995-01-01

    To assure the continued absence of uncontrolled condensed-phase chemical reactions in connection with the Hanford waste materials, efforts have been underway including both theoretical and experimental investigations to clarify the requirements for such reactions. This document defines the differences and requirements for homogeneous runaway and propagating chemical reactions incuding a discussion of general contact-temperature ignition (CTI) condition for propagating reactions that include the effect of moisture. The CTI condition implies that the contact temperature or interface temperature between reacted and unreacted materials must exceed the ignition temperature and is compared to experimental data including both synthetic ferrocyanide and surrogate organic materials. In all cases, the occurrences of ignition accompanied by self-propagating reactions are consistent with the theoretical anticipations of the CTI condition

  13. Development of a new densimeter for the combined investigation of dew-point densities and sorption phenomena of fluid mixtures

    Science.gov (United States)

    Moritz, Katharina; Kleinrahm, Reiner; McLinden, Mark O.; Richter, Markus

    2017-12-01

    For the determination of dew-point densities and pressures of fluid mixtures, a new densimeter has been developed. The new apparatus is based on the well-established two-sinker density measurement principle with the additional capability of quantifying sorption effects. In the vicinity of the dew line, such effects cause a change in composition of the gas mixture under study, which can significantly distort accurate density measurements. The new experimental technique enables the accurate measurement of dew-point densities and pressures and the quantification of sorption effects at the same time.

  14. Hysteresis in Lanthanide Zirconium Oxides Observed Using a Pulse CV Technique and including the Effect of High Temperature Annealing.

    Science.gov (United States)

    Lu, Qifeng; Zhao, Chun; Mu, Yifei; Zhao, Ce Zhou; Taylor, Stephen; Chalker, Paul R

    2015-07-29

    A powerful characterization technique, pulse capacitance-voltage (CV) technique, was used to investigate oxide traps before and after annealing for lanthanide zirconium oxide thin films deposited on n-type Si (111) substrates at 300 °C by liquid injection Atomic Layer Deposition (ALD). The results indicated that: (1) more traps were observed compared to the conventional capacitance-voltage characterization method in LaZrO x ; (2) the time-dependent trapping/de-trapping was influenced by the edge time, width and peak-to-peak voltage of a gate voltage pulse. Post deposition annealing was performed at 700 °C, 800 °C and 900 °C in N₂ ambient for 15 s to the samples with 200 ALD cycles. The effect of the high temperature annealing on oxide traps and leakage current were subsequently explored. It showed that more traps were generated after annealing with the trap density increasing from 1.41 × 10 12 cm -2 for as-deposited sample to 4.55 × 10 12 cm -2 for the 800 °C annealed one. In addition, the leakage current density increase from about 10 - ⁶ A/cm² at V g = +0.5 V for the as-deposited sample to 10 -3 A/cm² at V g = +0.5 V for the 900 °C annealed one.

  15. Hysteresis in Lanthanide Zirconium Oxides Observed Using a Pulse CV Technique and including the Effect of High Temperature Annealing

    Directory of Open Access Journals (Sweden)

    Qifeng Lu

    2015-07-01

    Full Text Available A powerful characterization technique, pulse capacitance-voltage (CV technique, was used to investigate oxide traps before and after annealing for lanthanide zirconium oxide thin films deposited on n-type Si (111 substrates at 300 °C by liquid injection Atomic Layer Deposition (ALD. The results indicated that: (1 more traps were observed compared to the conventional capacitance-voltage characterization method in LaZrOx; (2 the time-dependent trapping/de-trapping was influenced by the edge time, width and peak-to-peak voltage of a gate voltage pulse. Post deposition annealing was performed at 700 °C, 800 °C and 900 °C in N2 ambient for 15 s to the samples with 200 ALD cycles. The effect of the high temperature annealing on oxide traps and leakage current were subsequently explored. It showed that more traps were generated after annealing with the trap density increasing from 1.41 × 1012 cm−2 for as-deposited sample to 4.55 × 1012 cm−2 for the 800 °C annealed one. In addition, the leakage current density increase from about 10−6 A/cm2 at Vg = +0.5 V for the as-deposited sample to 10−3 A/cm2 at Vg = +0.5 V for the 900 °C annealed one.

  16. Prediction of the critical point and the dew- and bubble-point curves fo natural gases. Tennen gas no rinkaiten oyobi roten futten kyokusen no suisan

    Energy Technology Data Exchange (ETDEWEB)

    Endo, T. (Hitachi, Ltd., Tokyo (Japan)); Arai, D.; Uematsu, M. (Keio University, Tokyo (Japan). Faculty of Science and Technology)

    1993-02-25

    Related to the natural gas transport by pipeline, etc., the critical point, dew point and bubble point of natural gas were presumed by calculation through equation of state for determining the exact thermophysical values. The natural gas is multi-component mixed fluid which is represented by methane as a representative component. It considerably differs in composition by its place of origin. Because the conventional method was complicated in process for thermodynamically determining the most stable composition of phases, algorithm of phasic equilibrium was applied by the equation of state which used the discrimination method by Nitta, et al. for the therodynamic stability of phases. The method by Michelsen was applied to the flash calculation, and figuration of both dew point and bubble point curves, while that by Heidemann, et al. was done to the critical point calculation. Peng-Robinson's was applied to an equation of state. To start the calculation, the constant of seven two-component systems the main component of which was methane was determined as a function of temperature based on the actually measured gas/liquid equilibrium value. Then, possibility of calculatively presuming the thermophysical values was shown through comparison of the actually measured values with those obtained by applying the present method to the above systems. Finally, the presumption was made for the natural gas which differed in place of origin. 17 refs., 15 figs., 2 tabs.

  17. Dew formation on the surface of biological soil crusts in central European sand ecosystems

    Directory of Open Access Journals (Sweden)

    T. Fischer

    2012-11-01

    Full Text Available Dew formation was investigated in three developmental stages of biological soil crusts (BSC, which were collected along a catena of an inland dune and in the initial substrate. The Penman equation, which was developed for saturated surfaces, was modified for unsaturated surfaces and used for prediction of dewfall rates. The levels of surface saturation required for this approach were predicted using the water retention functions and the thicknesses of the BSCs. During a first field campaign (2–3 August 2011, dewfall increased from 0.042 kg m−2 for the initial sandy substrate to 0.058, 0.143 and 0.178 kg m−2 for crusts 1 to 3, respectively. During a second field campaign (17–18 August 2011, where dew formation was recorded in 1.5 to 2.75-h intervals after installation at 21:30 CEST, dewfall increased from 0.011 kg m−2 for the initial sandy substrate to 0.013, 0.028 and 0.055 kg m−2 for crusts 1 to 3, respectively. Dewfall rates remained on low levels for the substrate and for crust 1, and decreased overnight for crusts 2 and 3 (with crust 3 > crust 2 > crust 1 throughout the campaign. Dew formation was well reflected by the model response. The suggested mechanism of dew formation involves a delay in water saturation in near-surface soil pores and extracellular polymeric substances (EPS where the crusts were thicker and where the water capacity was high, resulting in elevated vapor flux towards the surface. The results also indicate that the amount of dewfall was too low to saturate the BSCs and to observe water flow into deeper soil. Analysis of the soil water retention curves revealed that, despite the sandy mineral matrix, moist crusts clogged by swollen EPS pores exhibited a clay-like behavior. It is hypothesized that BSCs gain double benefit from suppressing their competitors by runoff generation and from improving their water supply by dew collection. Despite higher amounts of dew, the

  18. Development of producing equipment of mixed butane-air with low dew point. Energy saving dewatering apparatus and 6A-Gas producing apparatus utilizing vaporization latent heat of butane and potential heat of air

    Energy Technology Data Exchange (ETDEWEB)

    Komine, Jin; Okada, Hiroto; Taniue, Nobuo; Tanoue, Keiju; Yamada, Tatsuhiko; Maekawa, Hisami; Murakami, Keiji

    1988-02-10

    A producing equipment of mixed butane-air with low dew point was developed. The dewatering was made during the period from the middle of May to the middle of October with high atmospheric humidity. The production capacity of the mixed gas is 3000 Nm/sup 3/ of 22% of butane and 78% of air per hour. The designed dew point is 18/sup 0/C or less under the pressure of 0.7 kg/cm/sup 2/G. The saturation temperature is 7.5/sup 0/C after the liquid butane is evacuated by a regulating valve. The air introduced into the dehumidifier through finned tubes is cooled to dewater based on those data. The partially vaporized butane is completely gasified by hot water in a vaporizer and mixed with the dewatered air by a venture mixer to produce the mixed butane-air. When the dewatering is incomplete, the spray nozzle must be just exchanged. The dew point of the produced gas was sufficiently below the designed value. The investment cost is low. The total operating cost is reduced by the remarkably decreased fuel cost though the power cost is increased. The noise level is low and the heat control is easy. (11 figs, 4 tabs, 1 photo)

  19. Selective oxidation of dual phase steel after annealing at different dew points

    Science.gov (United States)

    Lins, Vanessa de Freitas Cunha; Madeira, Laureanny; Vilela, Jose Mario Carneiro; Andrade, Margareth Spangler; Buono, Vicente Tadeu Lopes; Guimarães, Juliana Porto; Alvarenga, Evandro de Azevedo

    2011-04-01

    Hot galvanized steels have been extensively used in the automotive industry. Selective oxidation on the steel surface affects the wettability of zinc on steel and the grain orientation of inhibition layer (Fe-Al-Zn alloy) and reduces the iron diffusion to the zinc layer. The aim of this work is to identify and quantify selective oxidation on the surface of a dual phase steel, and an experimental steel with a lower content of manganese, annealed at different dew points. The techniques employed were atomic force microscopy, X-ray photoelectron spectroscopy, and glow discharge optical emission spectroscopy. External selective oxidation was observed for phosphorus on steel surface annealed at 0 °C dp, and for manganese, silicon, and aluminum at a lower dew point. The concentration of manganese was higher on the dual phase steel surface than on the surface of the experimental steel. The concentration of molybdenum on the surface of both steels increased as the depth increased.

  20. Sensitive skin at menopause; dew point and electrometric properties of the stratum corneum.

    Science.gov (United States)

    Paquet, F; Piérard-Franchimont, C; Fumal, I; Goffin, V; Paye, M; Piérard, G E

    1998-01-12

    A number of menopausal women experience skin sensitive to various environmental threats. Two panels of 15 menopausal women on or without HRT were compared. We studied the response of their stratum corneum to variations in environmental humidity, either in air or in response to an emollient. Environment dew point and electrometric measurements on the skin were recorded to search for correlations. Data show that the baseline stratum corneum hydration is influenced by the dew point. HRT improves the barrier function of the skin. The use of emollient further extends the improvement in the functional properties of skin in menopausal women. Both HRT and an emollient can counteract in part some of the deleterious effects of cold and dry weather.

  1. Measurement and estimation of dew point for SNG. [Comparison of calculated and measured values

    Energy Technology Data Exchange (ETDEWEB)

    Furuyama, Y.

    1974-08-01

    Toho Gas measured and estimated SNG dew points in high-pressure deliveries by calculating the theoretical values by the high-pressure gas-liquid equilibrium theory using the pressure-extrapolation method to reach K = 1, and the BWR method to estimate fugacity, then verifying these values experimentally. The experimental values were measured at 161.7 to 367.5 psi using the conventional static and circulation methods, in addition to a newly developed method consisting of circulating a known composition of gas mixtures, partially freezing them, and monitoring the dew point by observing the droplets on a mirror cooled by blowing liquid nitrogen. Good agreement was found between the calculated and the experimental values.

  2. Draught regulator with control flap lowers dew point, keeps stacks dry

    Energy Technology Data Exchange (ETDEWEB)

    Dreizler, U.; Dreizler, W.

    1982-11-30

    Draught regulators for auxiliary air are particularly important in older stacks operated with new boilers and burners. Owing to better ventilation during burner operation and standstill, the dew point of flue gases will be lowered so that water vapour condensation will be prevented. Postfitting of draught regulators will also help in stacks already damaged by condensation water. The draught regulator has a control flap for better control of auxiliary air supply.

  3. Test and evaluation of the Fort St. Vrain dew point moisture monitor system

    International Nuclear Information System (INIS)

    Block, G.A.; Del Bene, J.V. Jr.; Gitterman, M.; Hastings, G.A.; Hawkins, W.M.; Hinz, R.F.; McCue, D.E.; Swanson, L.L.; Vavrina, J.; Zwetzig, G.B.

    1975-01-01

    Descriptions are given of the Fort St. Vrain Dew Point Moisture Monitor (DPMM) System; the bases for the DPMM system response time requirements for safety related functions at the required reactor operating conditions; the results and evaluation of recent testing which measured the performance of the current system at simulated operating conditions; predicted response times for reactor power operation from 0 to 100 percent and a modification to provide improved response times for low-load and plant start-up conditions

  4. Characterisation of a microwave re-entrant cavity resonator for phase-equilibrium measurements and new dew-point data for a (0.25 argon + 0.75 carbon dioxide) mixture

    International Nuclear Information System (INIS)

    Tsankova, Gergana; Richter, Markus; Madigan, Adele; Stanwix, Paul L.; May, Eric F.; Span, Roland

    2016-01-01

    Highlights: • A microwave reentrant cavity resonator was refurbished and extensively characterised. • Vacuum resonance frequencies and Q-factors were modelled and experimentally validated. • Whispering gallery-type modes first-time reported for present cavity geometry. • Dew points of a (0.2491 argon + 0.7509 carbon dioxide) mixture were measured. • Measurements were carried out from T = (252–280) K at pressures up to 6.9 MPa. - Abstract: An apparatus based on a microwave re-entrant cavity resonator, originally built for accurate measurements of the dielectric permittivity of natural gas mixtures, was refurbished and extensively characterised. This was done to enable the future investigation of phase equilibria and (p, ρ, T, x) behaviour of fluid mixtures utilizing the present experimental technique. Vacuum resonance frequencies and Q-factors of the resonator’s modes were modelled using both analytic and finite element methods, and found to compare well with experimental values. The finite element models helped to identify two whispering gallery-type modes not previously reported for such cavity geometries. The models also predict distributions of the electric and magnetic fields in the re-entrant cavity resonator useful for identifying regions in the cavity more sensitive to the presence of a liquid. Following the resonator’s characterisation, its ability to measure dew points was tested using a gravimetrically prepared (0.2501 argon + 0.7499 carbon dioxide) mixture over the temperature range from (252 to 280) K at pressures from (2.8 to 6.9) MPa. The combined expanded uncertainty with a level of confidence of approximately 95% (k = 2) in dew-point temperature and pressure ranged between (0.025 and 0.044) K and from (0.009 to 0.015) MPa, respectively. We compared the experimental dew-point pressures with the recently developed multi-parameter equation of state optimised for combustion gases (EOS-CG), showing relative deviations in the range of (0

  5. Developmental responses of bread wheat to changes in ambient temperature following deletion of a locus that includes FLOWERING LOCUS T1.

    Science.gov (United States)

    Dixon, Laura E; Farré, Alba; Finnegan, E Jean; Orford, Simon; Griffiths, Simon; Boden, Scott A

    2018-01-04

    FLOWERING LOCUS T (FT) is a central integrator of environmental signals that regulates the timing of vegetative to reproductive transition in flowering plants. In model plants, these environmental signals have been shown to include photoperiod, vernalization, and ambient temperature pathways, and in crop species, the integration of the ambient temperature pathway remains less well understood. In hexaploid wheat, at least 5 FT-like genes have been identified, each with a copy on the A, B, and D genomes. Here, we report the characterization of FT-B1 through analysis of FT-B1 null and overexpression genotypes under different ambient temperature conditions. This analysis has identified that the FT-B1 alleles perform differently under diverse environmental conditions; most notably, the FT-B1 null produces an increase in spikelet and tiller number when grown at lower temperature conditions. Additionally, absence of FT-B1 facilitates more rapid germination under both light and dark conditions. These results provide an opportunity to understand the FT-dependent pathways that underpin key responses of wheat development to changes in ambient temperature. This is particularly important for wheat, for which development and grain productivity are sensitive to changes in temperature. © 2018 The Authors Plant, Cell & Environment Published by John Wiley & Sons Ltd.

  6. A Calibration Facility for Dew Point in Air up to 1 MPa

    Science.gov (United States)

    Carroll, P. A.; Bell, S. A.; Stevens, M.

    2015-12-01

    The provision of primary dew-point standards for humidified air and nitrogen at atmospheric pressure is well established, and measurement traceability to these standards provides confidence in a vast number of air humidity measurements. However, hygrometers are used industrially at a wide range of pressures. Both the performance of hygrometers and the properties of humid gases are known to vary with gas pressure. The pressure-dependence of gas non-ideality for air-water mixtures (water-vapor enhancement factor) is well enough known at moderate pressures, but there remains a need to characterize hygrometers at the pressure of use. To address this, a humidity calibration capability of wider scope is under development at the UK National Physical Laboratory (NPL). As an initial stage in the development of this capability, a humidity standard generating air or nitrogen in the dew-point range from -60° C to +10° C, at pressures up to 1 MPa (10 bar) has been validated for the calibration of hygrometers. The expanded uncertainty of the dew-point generator in this range with a coverage factor k= 2 is ± 0.07° C.

  7. Fuzzy logic prediction of dew point pressure of selected Iranian gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Nowroozi, Saeed [Shahid Bahonar Univ. of Kerman (Iran); Iranian Offshore Oil Company (I.O.O.C.) (Iran); Ranjbar, Mohammad; Hashemipour, Hassan; Schaffie, Mahin [Shahid Bahonar Univ. of Kerman (Iran)

    2009-12-15

    The experimental determination of dew point pressure in a window PVT cell is often difficult especially in the case of lean retrograde gas condensate. Besides all statistical, graphical and experimental methods, the fuzzy logic method can be useful and more reliable for estimation of reservoir properties. Fuzzy logic can overcome uncertainty existent in many reservoir properties. Complexity, non-linearity and vagueness are some reservoir parameter characteristics, which can be propagated simply by fuzzy logic. The fuzzy logic dew point pressure modeling system used in this study is a multi input single output (MISO) Mamdani system. The model was developed using experimentally constant volume depletion (CVD) measured samples of some Iranian fields. The performance of the model is compared against the performance of some of the most accurate and general correlations for dew point pressure calculation. Results show that this novel method is more accurate and reliable with an average absolute deviation of 1.33% and 2.68% for developing and checking, respectively. (orig.)

  8. Novel ideas for maximising dew collection to aid plant establishment to combat desertification and restore degraded dry and arid lands

    Science.gov (United States)

    Kotzen, Benz

    2014-05-01

    This paper focuses on the potential of dew to provide water to plants and potentially to people as well in remote and difficult to reach areas where rainfall and underground water cannot be harvested. The combat of desertification and the restoration of degraded and desertified dry and arid lands has never been more urgent. A key practical component of this strategy is the restoration of habitat with planting. But for habitat and planting to survive there needs to be an adequate supply of water. In most cases providing water to the plant's roots is vital. In some areas where habitats have been destroyed, sufficient water is immediately available, for example through seasonal rainfall, or it can be harvested to concentrate adequate supplies of water to the roots. However, in arid and hyper arid areas, as well as in some dryland areas, a consistent and adequate supply of water cannot be provided by any conventional proven method. Thus, as the need to combat desertification and to restore desertified dry and arid land increases, so the need to find novel methods of establishing and maintaining planting and thus habitat increases. In more traditional land management scenarios this can be achieved through manipulating landform on a micro and macro scale, for example, by creating catchments, thereby collecting precipitation and directing it to the plants. Where this cannot be done, other means of water supply are usually required. Bainbridge (2007) and others have shown that supplying water to plants is possible through a number of traditional methods, for example, using clay pots. But most of these techniques require an introduced source of water, for example, obtained through water harvesting methods or by delivering water to site in tanks and by water bowser. This can work but requires continuous manpower. It is expensive and can be physically prohibitive in areas where access is difficult and/or remote. The concept of using dew to supply water in drylands is not new

  9. Effect of dew point on the formation of surface oxides of twinning-induced plasticity steel

    International Nuclear Information System (INIS)

    Kim, Yunkyum; Lee, Joonho; Shin, Kwang-Soo; Jeon, Sun-Ho; Chin, Kwang-Geun

    2014-01-01

    The surface oxides of twinning-induced plasticity (TWIP) steel annealed at 800 °C for 43 s were investigated using transmission electron microscopy. During the annealing process, the oxygen potential was controlled by adjusting the dew point in a 15%H 2 –N 2 gas atmosphere. It was found that the type of surface oxides formed and the thickness of the oxide layer were determined by the dew point. In a gas mixture with a dew point of − 20 °C, a MnO layer with a thickness of ∼ 100 nm was formed uniformly on the steel surface. Under the MnO layer, a MnAl 2 O 4 layer with a thickness of ∼ 15 nm was formed with small Mn 2 SiO 4 particles that measured ∼ 70 nm in diameter. Approximately 500 nm below the MnAl 2 O 4 layer, Al 2 O 3 was formed at the grain boundaries. On the other hand, in a gas mixture with a dew point of − 40 °C, a MnAl 2 O 4 layer with a thickness of ∼ 5 nm was formed on most parts of the surface. On some parts of the surface, Mn 2 SiO 4 particles were formed irregularly up to a thickness of ∼ 50 nm. Approximately 200 nm below the MnAl 2 O 4 layer, Al 2 O 3 was found at the grain boundaries. Thermodynamic calculations were performed to explain the experimental results. The calculations showed that when a O2 > ∼ 1.26 × 10 −28 , MnO, MnAl 2 O 4 , and Mn 2 SiO 4 can be formed together, and the major oxide is MnO. When a O2 is in the range of 1.26 × 10 −28 –2.51 × 10 −31 , MnO is not stable but MnAl 2 O 4 is the major oxide. When a O2 < ∼ 2.51 × 10 −31 , only Al 2 O 3 is stable. Consequently, the effective activity of oxygen is considered the dominant factor in determining the type and shape of surface oxides of TWIP steel. - Highlights: • The surface oxides of TWIP steel annealed at 800 °C were investigated using TEM. • The surface oxides were determined by the dew point during the annealing process. • The activity of oxygen is the major factor determining the oxides of TWIP steel

  10. Theory, Electro-Optical Design, Testing, and Calibration of a Prototype Atmospheric Supersaturation, Humidity, and Temperature Sensor.

    Science.gov (United States)

    1982-07-15

    Voltage versus Aspirated Dew Point 94 Hygrometer Reading in Degrees Celsius (10 Second Averages) Fig. (7.5)(b) Scatter Diagram - NCAR Lyman-Alpha...Hygrometer Output Voltage versus Aspirated Dew Point Hygrometer Reading in Degrees Celsius (10 Second Averages) Fig. (7.6) Ophir Air Temperature...goal thus translates to an absolute humidity accuracy of 1% of reading or better over a dynamic r-dnj(! ,(f i(jul. 4 uder. of magnitude. 29 - ITI VAP

  11. Localisation inhabituelle du sarcome d'Ewing des parties molles ...

    African Journals Online (AJOL)

    Ewing's sarcoma of soft parts is a rare mesenchymal tumor of poor prognosis. Receiving an early diagnosis increases the chance of survival. In the absence of clinical and radiological features, it seems necessary to include it in the differential diagnosis which includes all the primitive tumour of soft parts and to hypothesize ...

  12. Improving indoor air quality through the use of continual multipoint monitoring of carbon dioxide and dew point.

    Science.gov (United States)

    Bearg, D W

    1998-09-01

    This article summarizes an approach for improving the indoor air quality (IAQ) in a building by providing feedback on the performance of the ventilation system. The delivery of adequate quantities of ventilation to all building occupants is necessary for the achievement of good IAQ. Feedback on the performance includes information on the adequacy of ventilation provided, the effectiveness of the distribution of this air, the adequacy of the duration of operation of the ventilation system, and the identification of leakage into the return plenum, either of outdoor or supply air. Keeping track of ventilation system performance is important not only in terms of maintaining good IAQ, but also making sure that this system continues to perform as intended after changes in building use. Information on the performance of the ventilation system is achieved by means of an automated sampling system that draws air from multiple locations and delivers it to both a carbon dioxide monitor and dew point sensor. The use of single shared sensors facilitates calibration checks as well as helps to guarantee data integrity. This approach to monitoring a building's ventilation system offers the possibility of achieving sustainable performance of this important aspect of good IAQ.

  13. Dew inspired breathing-based detection of genetic point mutation visualized by naked eye

    Science.gov (United States)

    Xie, Liping; Wang, Tongzhou; Huang, Tianqi; Hou, Wei; Huang, Guoliang; Du, Yanan

    2014-09-01

    A novel label-free method based on breathing-induced vapor condensation was developed for detection of genetic point mutation. The dew-inspired detection was realized by integration of target-induced DNA ligation with rolling circle amplification (RCA). The vapor condensation induced by breathing transduced the RCA-amplified variances in DNA contents into visible contrast. The image could be recorded by a cell phone for further or even remote analysis. This green assay offers a naked-eye-reading method potentially applied for point-of-care liver cancer diagnosis in resource-limited regions.

  14. Wärtsilä turbocharger wash and dew point controller integration

    OpenAIRE

    Perälä, Antti

    2013-01-01

    There are two separate control cabinets used in Wärtsilä marine solutions, Turbocharger Wash Control and the Dew Point Control. The cabinets contain similar PLCs with I/O-cards needed in the system and touch screen for monitoring and controlling purposes. The purpose of the thesis was to find and implement a solution for integration of the control cabinets. The advantages of the integration are savings in material, space in the engine room and amount of work. The aim of the project was to cre...

  15. [Antibacterial actin of vinegar against food-borne pathogenic bacteria including Escherichia coli O157:H7 (Part 2). Effect of sodium chloride and temperature on bactericidal activity].

    Science.gov (United States)

    Entani, E; Asai, M; Tsujihata, S; Tsukamoto, Y; Ohta, M

    1997-05-01

    Bactericidal effects of various kinds of AWASEZU (processed vinegar, 2.5% acidity) on food-borne pathogenic bacteria including Escherichia coli O157:H7 and other bacteria were examined. the order of bactericidal activities was NIHAIZU (3.5% NaCl was added) > SANBA-IZU (3.5% NaCl and 10% sucrose were added) > plain vinegar (spirit vinegar) > AMAZU (10% sucrose was added). This indicates that their activities were enhanced by the addition of sodium chloride and suppressed by the addition of sugar. On the other hand, when soy sauce was used instead of sodium chloride, the order of bactericidal activities was plain vinegar > AMAZU > NIHAIZU > SANBAIZU. This is mainly because their activities were suppressed by the increase in the pH value. The effect of sodium chloride (0.01-15%) and temperature (10-50 degrees C) on bactericidal activities against E. coli O157:H7 in spirit vinegar (0.5-2.5% acidity) was further examined. When vinegar was used in combination with sodium chloride, predominant synergism on the bactericidal activity was observed. Their activities were markedly enhanced by the addition of sodium chloride in proportion to the concentration. In addition to this, at higher temperatures spirit vinegar killed bacteria much more rapidly. It should be noted that the bactericidal activity of spirit vinegar was extremely enhanced by the combined use of the addition of sodium chloride and the rise of temperature. For example, in 2.5% acidity vinegar, the time required for 3 log decrease in viable cell numbers at 20 degrees C was shortened to 1/140-fold by the addition of 5% sodium chloride, shortened to 1/51-fold by the rise of the reaction temperature at 40 degrees C, and shortened to 1/830-fold; 0.89 minutes by both the addition of 5% sodium chloride and the rise of temperature at 40 degrees C. In order to propose the methods to prevent food poisoning by bacterial infection, bactericidal activities of vinegar solution containing sodium chloride on cooking tools and

  16. Effect of dew point on the formation of surface oxides of twinning-induced plasticity steel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yunkyum [Department of Materials Science and Engineering, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 136–713 (Korea, Republic of); Lee, Joonho, E-mail: joonholee@korea.ac.kr [Department of Materials Science and Engineering, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 136–713 (Korea, Republic of); Shin, Kwang-Soo [Research Institute of Industrial Science and Technology, Pohang 790–600 (Korea, Republic of); Jeon, Sun-Ho; Chin, Kwang-Geun [POSCO Technical Research Laboratories, Gwangyang 545–090 (Korea, Republic of)

    2014-03-01

    The surface oxides of twinning-induced plasticity (TWIP) steel annealed at 800 °C for 43 s were investigated using transmission electron microscopy. During the annealing process, the oxygen potential was controlled by adjusting the dew point in a 15%H{sub 2}–N{sub 2} gas atmosphere. It was found that the type of surface oxides formed and the thickness of the oxide layer were determined by the dew point. In a gas mixture with a dew point of − 20 °C, a MnO layer with a thickness of ∼ 100 nm was formed uniformly on the steel surface. Under the MnO layer, a MnAl{sub 2}O{sub 4} layer with a thickness of ∼ 15 nm was formed with small Mn{sub 2}SiO{sub 4} particles that measured ∼ 70 nm in diameter. Approximately 500 nm below the MnAl{sub 2}O{sub 4} layer, Al{sub 2}O{sub 3} was formed at the grain boundaries. On the other hand, in a gas mixture with a dew point of − 40 °C, a MnAl{sub 2}O{sub 4} layer with a thickness of ∼ 5 nm was formed on most parts of the surface. On some parts of the surface, Mn{sub 2}SiO{sub 4} particles were formed irregularly up to a thickness of ∼ 50 nm. Approximately 200 nm below the MnAl{sub 2}O{sub 4} layer, Al{sub 2}O{sub 3} was found at the grain boundaries. Thermodynamic calculations were performed to explain the experimental results. The calculations showed that when a{sub O2} > ∼ 1.26 × 10{sup −28}, MnO, MnAl{sub 2}O{sub 4}, and Mn{sub 2}SiO{sub 4} can be formed together, and the major oxide is MnO. When a{sub O2} is in the range of 1.26 × 10{sup −28}–2.51 × 10{sup −31}, MnO is not stable but MnAl{sub 2}O{sub 4} is the major oxide. When a{sub O2} < ∼ 2.51 × 10{sup −31}, only Al{sub 2}O{sub 3} is stable. Consequently, the effective activity of oxygen is considered the dominant factor in determining the type and shape of surface oxides of TWIP steel. - Highlights: • The surface oxides of TWIP steel annealed at 800 °C were investigated using TEM. • The surface oxides were determined by the dew point

  17. High Temperature Superconductors: From Delivery to Applications (Presentation from 2011 Ernest Orlando Lawrence Award-winner, Dr. Amit Goyal, and including introduction by Energy Secretary, Dr. Steven Chu)

    International Nuclear Information System (INIS)

    Goyal, Amit

    2012-01-01

    Dr. Amit Goyal, a high temperature superconductivity (HTS) researcher at Oak Ridge National Laboratory, was named a 2011 winner of the Department of Energy's Ernest Orlando Lawrence Award honoring U.S. scientists and engineers for exceptional contributions in research and development supporting DOE and its mission. Winner of the award in the inaugural category of Energy Science and Innovation, Dr. Goyal was cited for his work in 'pioneering research and transformative contributions to the field of applied high temperature superconductivity, including fundamental materials science advances and technical innovations enabling large-scale applications of these novel materials.' Following his basic research in grain-to-grain supercurrent transport, Dr. Goyal focused his energy in transitioning this fundamental understanding into cutting-edge technologies. Under OE sponsorship, Dr. Goyal co-invented the Rolling Assisted Bi-Axially Textured Substrate technology (RABiTS) that is used as a substrate for second generation HTS wires. OE support also led to the invention of Structural Single Crystal Faceted Fiber Substrate (SSIFFS) and the 3-D Self Assembly of Nanodot Columns. These inventions and associated R and D resulted in 7 R and D 100 Awards including the 2010 R and D Magazine's Innovator of the Year Award, 3 Federal Laboratory Consortium Excellence in Technology Transfer National Awards, a DOE Energy100 Award and many others. As a world authority on HTS materials, Dr. Goyal has presented OE-sponsored results in more than 150 invited talks, co-authored more than 350 papers and is a fellow of 7 professional societies.

  18. Effects of leaf hair points of a desert moss on water retention and dew formation: implications for desiccation tolerance.

    Science.gov (United States)

    Tao, Ye; Zhang, Yuan Ming

    2012-05-01

    Leaf hair points (LHPs) are important morphological structures in many desiccation-tolerant mosses, but study of their functions has been limited. A desert moss, Syntrichia caninervis, was chosen for examination of the ecological effects of LHPs on water retention and dew formation at individual and population (patch) levels. Although LHPs were only 4.77% of shoot weight, they were able to increase absolute water content (AWC) by 24.87%. The AWC of samples with LHPs was always greater than for those without LHPs during dehydration. The accumulative evaporation ratio (AER) showed an opposite trend. AWC, evaporation ratio and AER of shoots with LHPs took 20 min longer to reach a completely dehydrated state than shoots without LHPs. At the population level, dew formation on moss crusts with LHPs was faster than on crusts without LHPs, and the former had higher daily and total dew amounts. LHPs were able to improve dew amounts on crusts by 10.26%. Following three simulated rainfall events (1, 3 and 6 mm), AERs from crusts with LHPs were always lower than from crusts without LHPs. LHPs can therefore significantly delay and reduce evaporation. We confirm that LHPs are important desiccation-tolerant features of S. caninervis at both individual and population levels. LHPs greatly aid moss crusts in adapting to arid conditions.

  19. CANDU pressure tube leak detection by annulus gas dew point measurement. A critical review

    Energy Technology Data Exchange (ETDEWEB)

    Greening, F.R. [CTS-NA, Tiverton, ON (Canada)

    2017-03-15

    In the event of a pressure tube leak from a small through-wall crack during CANDU reactor operations, there is a regulatory requirement - referred to as Leak Before Break (LBB) - for the licensee to demonstrate that there will be sufficient time for the leak to be detected and the reactor shut down before the crack grows to the critical size for fast-uncontrolled rupture. In all currently operating CANDU reactors, worldwide, this LBB requirement is met via continuous dew point measurements of the CO{sub 2} gas circulating in the reactor's Annulus Gas System (AGS). In this paper the historical development and current status of this leak detection capability is reviewed and the use of moisture injection tests as a verification procedure is critiqued. It is concluded that these tests do not represent AGS conditions that are to be expected in the event of a real pressure tube leak.

  20. The change of steel surface chemistry regarding oxygen partial pressure and dew point

    Science.gov (United States)

    Norden, Martin; Blumenau, Marc; Wuttke, Thiemo; Peters, Klaus-Josef

    2013-04-01

    By investigating the surface state of a Ti-IF, TiNb-IF and a MnCr-DP after several series of intercritical annealing, the impact of the annealing gas composition on the selective oxidation process is discussed. On behalf of the presented results, it can be concluded that not the general oxygen partial pressure in the annealing furnace, which is a result of the equilibrium reaction of water and hydrogen, is the main driving force for the selective oxidation process. It is shown that the amounts of adsorbed gases at the strip surface and the effective oxygen partial pressure resulting from the adsorbed gases, which is mainly dependent on the water content of the annealing furnace, is driving the selective oxidation processes occurring during intercritical annealing. Thus it is concluded, that for industrial applications the dew point must be the key parameter value for process control.

  1. CANDU pressure tube leak detection by annulus gas dew point measurement. A critical review

    International Nuclear Information System (INIS)

    Greening, F.R.

    2017-01-01

    In the event of a pressure tube leak from a small through-wall crack during CANDU reactor operations, there is a regulatory requirement - referred to as Leak Before Break (LBB) - for the licensee to demonstrate that there will be sufficient time for the leak to be detected and the reactor shut down before the crack grows to the critical size for fast-uncontrolled rupture. In all currently operating CANDU reactors, worldwide, this LBB requirement is met via continuous dew point measurements of the CO_2 gas circulating in the reactor's Annulus Gas System (AGS). In this paper the historical development and current status of this leak detection capability is reviewed and the use of moisture injection tests as a verification procedure is critiqued. It is concluded that these tests do not represent AGS conditions that are to be expected in the event of a real pressure tube leak.

  2. Catalysts macroporosity and their efficiency in sulphur sub-dew point Claus tail gas treating processes

    Energy Technology Data Exchange (ETDEWEB)

    Tsybulevski, A.M.; Pearson, M. [Alcoa Industrial Chemicals, 16010 Barker`s Point Lane, Houston, TX (United States); Morgun, L.V.; Filatova, O.E. [All-Russian Research Institute of Natural Gases and Gas Technologies VNIIGAZ, Moscow (Russian Federation); Sharp, M. [Porocel Corporation, Westheimer, Houston, TX (United States)

    1996-10-08

    The efficiency of 4 samples of alumina catalyst has been studied experimentally in the course of the Claus `tail gas` treating processes at the sulphur sub-dew point (TGTP). The samples were characterized by the same chemical and crystallographic composition, the same volume of micropores, the same surface area and the same catalytic activity but differed appreciably in the volume of macropores. An increase in the effective operation time of the catalysts before breakthrough of unrecoverable sulphur containing compounds, with the increasing macropore volume has been established. A theoretical model of the TGTP has been considered and it has been shown that the increase in the sulphur capacity of the catalysts with a larger volume of macropores is due to an increase in the catalysts efficiency factor and a slower decrease in their diffusive permeability during filling of micropores by sulphur

  3. Characterization of SiO2/SiC interface states and channel mobility from MOSFET characteristics including variable-range hopping at cryogenic temperature

    Directory of Open Access Journals (Sweden)

    Hironori Yoshioka

    2018-04-01

    Full Text Available The characteristics of SiC MOSFETs (drain current vs. gate voltage were measured at 0.14−350 K and analyzed considering variable-range hopping conduction through interface states. The total interface state density was determined to be 5.4×1012 cm−2 from the additional shift in the threshold gate voltage with a temperature change. The wave-function size of interface states was determined from the temperature dependence of the measured hopping current and was comparable to the theoretical value. The channel mobility was approximately 100 cm2V−1s−1 and was almost independent of temperature.

  4. Characterization of SiO2/SiC interface states and channel mobility from MOSFET characteristics including variable-range hopping at cryogenic temperature

    Science.gov (United States)

    Yoshioka, Hironori; Hirata, Kazuto

    2018-04-01

    The characteristics of SiC MOSFETs (drain current vs. gate voltage) were measured at 0.14-350 K and analyzed considering variable-range hopping conduction through interface states. The total interface state density was determined to be 5.4×1012 cm-2 from the additional shift in the threshold gate voltage with a temperature change. The wave-function size of interface states was determined from the temperature dependence of the measured hopping current and was comparable to the theoretical value. The channel mobility was approximately 100 cm2V-1s-1 and was almost independent of temperature.

  5. Use of dew-point hygrometry, direct sweat collection, and measurement of body water losses to determine sweating rates in exercising horses.

    Science.gov (United States)

    Kingston, J K; Geor, R J; McCutcheon, L J

    1997-02-01

    To compare dew-point hygrometry, direct sweat collection, and measurement of body water loss as methods for determination of sweating rate (SR) in exercising horses. 6 exercise-trained Thoroughbreds. SR was measured in 6 horses exercising at 40% of the speed that elicited maximum oxygen consumption for 45 km, with a 15-minute rest at the end of each 15-km phase. Each horse completed 2 exercise trials. Dew-point hygrometry, as a method of local SR determination, was validated in vitro by measurement of rate of evaporative water loss. During exercise, local SR was determined every 10 minutes by the following 2 methods: (1) dew-point hygrometry on the neck and lateral area of the thorax, and (2) on the basis of the volume of sweat collected from a sealed plastic pouch attached to the lateral area of the thorax. Mean whole body SR was calculated from total body water loss incurred during exercise. Evaporation rate measured by use of dew-point hygrometry was significantly correlated (r2 = 0.92) with the actual rate of evaporative water loss. There was a similar pattern of change in SR measured by dew-point hygrometry on the neck and lateral area of the thorax during exercise, with a significantly higher SR on the neck. The SR measured on the thorax by direct sweat collection and by dew-point hygrometry were of similar magnitude. Mean whole body SR calculated from total body water loss was not significantly different from mean whole body SR estimated from direct sweat collection or dew-point hygrometry measurements on the thorax. Dew-point hygrometry and direct sweat collection are useful methods for determination of local SR in horses during prolonged, steady-state exercise in moderate ambient conditions. Both methods of local SR determination provide an accurate estimated of whole body SR.

  6. Prediction of temperature and damage in an irradiated human eye-Utilization of a detailed computer model which includes a vectorial blood stream in the choroid.

    Science.gov (United States)

    Heussner, Nico; Holl, Lukas; Nowak, Timo; Beuth, Thorsten; Spitzer, Martin S; Stork, Wilhelm

    2014-08-01

    The work presented here describes the development and use of a three-dimensional thermo-dynamic model of the human eye for the prediction of temperatures and damage thresholds under irradiation. This model takes into account the blood flow by the implementation of a vectorial blood stream in the choroid and also uses the actual physiological extensions and tissue parameters of the eye. Furthermore it considers evaporation, radiation and convection at the cornea as well as the eye lid. The predicted temperatures were successfully validated against existing eye models in terms of corneal and global thermal behaviour. The model׳s predictions were additionally checked for consistency with in-vivo temperature measurements of the cornea, the irradiated retina and its damage thresholds. These thresholds were calculated from the retinal temperatures using the Arrhenius integral. Hence the model can be used to predict the temperature increase and irradiation hazard within the human eye as long as the absorption values and the Arrhenius coefficients are known and the damage mechanism is in the thermal regime. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. A physically based analytical spatial air temperature and humidity model

    Science.gov (United States)

    Yang, Yang; Endreny, Theodore A.; Nowak, David J.

    2013-09-01

    Spatial variation of urban surface air temperature and humidity influences human thermal comfort, the settling rate of atmospheric pollutants, and plant physiology and growth. Given the lack of observations, we developed a Physically based Analytical Spatial Air Temperature and Humidity (PASATH) model. The PASATH model calculates spatial solar radiation and heat storage based on semiempirical functions and generates spatially distributed estimates based on inputs of topography, land cover, and the weather data measured at a reference site. The model assumes that for all grids under the same mesoscale climate, grid air temperature and humidity are modified by local variation in absorbed solar radiation and the partitioning of sensible and latent heat. The model uses a reference grid site for time series meteorological data and the air temperature and humidity of any other grid can be obtained by solving the heat flux network equations. PASATH was coupled with the USDA iTree-Hydro water balance model to obtain evapotranspiration terms and run from 20 to 29 August 2010 at a 360 m by 360 m grid scale and hourly time step across a 285 km2 watershed including the urban area of Syracuse, NY. PASATH predictions were tested at nine urban weather stations representing variability in urban topography and land cover. The PASATH model predictive efficiency R2 ranged from 0.81 to 0.99 for air temperature and 0.77 to 0.97 for dew point temperature. PASATH is expected to have broad applications on environmental and ecological models.

  8. Internal state variable plasticity-damage modeling of AISI 4140 steel including microstructure-property relations: temperature and strain rate effects

    Science.gov (United States)

    Nacif el Alaoui, Reda

    Mechanical structure-property relations have been quantified for AISI 4140 steel. under different strain rates and temperatures. The structure-property relations were used. to calibrate a microstructure-based internal state variable plasticity-damage model for. monotonic tension, compression and torsion plasticity, as well as damage evolution. Strong stress state and temperature dependences were observed for the AISI 4140 steel. Tension tests on three different notched Bridgman specimens were undertaken to study. the damage-triaxiality dependence for model validation purposes. Fracture surface. analysis was performed using Scanning Electron Microscopy (SEM) to quantify the void. nucleation and void sizes in the different specimens. The stress-strain behavior exhibited. a fairly large applied stress state (tension, compression dependence, and torsion), a. moderate temperature dependence, and a relatively small strain rate dependence.

  9. Temperatures and locations used by hibernating bats, including Myotis sodalis (Indiana bat), in a limestone mine: implications for conservation and management.

    Science.gov (United States)

    Brack, Virgil

    2007-11-01

    Understanding temperatures used by hibernating bats will aid conservation and management efforts for many species. A limestone mine with 71 km of passages, used as a hibernaculum by approximately 30,000 bats, was visited four times during a 6-year period. The mine had been surveyed and mapped; therefore, bats could be precisely located and temperatures (T (s)) of the entire hibernaculum ceiling accurately mapped. It was predicted that bats should hibernate between 5 and 10 degrees C to (1) use temperatures that allow a near minimal metabolic rate, (2) maximize the duration of hibernation bouts, (3) avoid more frequent and prolonged arousal at higher temperatures, (4) avoid cold and freezing temperatures that require an increase in metabolism and a decrease in duration of hibernation bouts or that could cause death, and (5) balance benefits of a reduced metabolic rate and costs of metabolic depression. The distribution of each species was not random for location (P block walls and sheltered alcoves, which perhaps dampened air movement and temperature fluctuations. Myotis lucifugus (little brown myotis) hibernated in colder, more variable areas (X = 7.2 +/- 2.6 degrees C). Myotis septentrionalis (northern myotis), Pipistrellus subflavus (eastern pipistrelle), and Eptesicus fuscus (big brown bat) typically hibernated in warm, thermally stable areas (X = 9.1 +/- 0.2 degrees C, X = 9.6 +/- 1.9 degrees C, and X = 9.5 +/- 1.5 degrees C, respectively). These data do not indicate that hibernacula for M. sodalis, an endangered species, should be manipulated to cool below 5 degrees C.

  10. Development of ultra low dew-point clean air generator; Cho tei roten seijo kuki hassei sochi no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, H.; Okamura, N. [Takasago thermal Engineering Co., Ltd., Kanagawa (Japan)

    2000-05-10

    To reduce the manufacturing cost of semiconductors, some systems have been proposed that use a cheap and high purity Clean Dry Air (CDA). CDA can reduce process step such as wafer cleaning, because CDA flow in stocker prevents the wafer surface from adsorbing of moisture and organic impurities. We have already optimized a two-stage rotary dehumidifier and have conducted a study of methods for cheaply manufacturing air that has a low dew-point of -70 degree C to -50 degree C. We have further developed the method in which a dry dehumidifier is used, and developed an ultra low dew-point air generator. The air generator is a three-stage rotary dehumidifier in which a further stage is added to the two-stage rotary dehumidifier. The main component of the rotors is metal silicate. The air generator can supply dry air with a dew-point of -110 degree C. or less, in which the concentration in all gaseous contaminants is far below 1 ppb. We made a trial calculation of the manufacturing cost, and an average cost of 0.25 yen/m{sup 3} was obtained. (author)

  11. Dew point, internal gas pressure, and chemical composition of the gas within the free volume of DWPF canistered waste forms

    International Nuclear Information System (INIS)

    Harbour, J.R.; Herman, D.T.; Crump, S.; Miller, T.J.; McIntosh, J.

    1996-01-01

    The Defense Waste Processing Facility (DWPF) produced 55 canistered waste forms containing simulated waste glass during the four Waste Qualification campaigns of the DWPF Startup Test Program. Testing of the gas within the free volume of these canisters for dew point, internal gas pressure, and chemical composition was performed as part of a continuing effort to demonstrate compliance with the Waste Acceptance Product Specifications. Results are presented for six glass-filled canisters. The dew points within the canisters met the acceptance criterion of < 20 degrees C for all six canisters. Factors influencing the magnitude of the dew point are presented. The chemical composition of the free volume gas was indistinguishable from air for all six canisters. Hence, no foreign materials were present in the gas phase of these canisters. The internal gas pressures within the sealed canisters were < 1 atm at 25 degrees C for all six canisters which readily met the acceptance criterion of an internal gas pressure of less than 1.5 atm at 25 degrees C. These results provided the evidence required to demonstrate compliance with the Waste Acceptance Product Specifications

  12. Hygromorphic Scales for Use in Water from Morning Dew and Elementary Model of Hydrogel Expansion Properties

    Science.gov (United States)

    Margolis, Nate

    Secure access to water is a growing problem in the world today. Millions of people do not have contact with fresh or clean water for drinking. Consuming dirty water leads to many illnesses and deaths every year. When water is scarce people are less likely to follow basic hygiene which also adds to the problem of sickness from water. Currently most of the population gets their water from run-off such as rivers, lakes and other fresh water bodies. Aquafers can also provide water, however, once they do not replenish themselves so once they are empty they will no longer provide a fresh water source. This is a serious problem because the population has grown to 7 billion people and only 2% of the world's water is fresh water. Of this, most the fresh water is locked in the polar ice caps. This leaves only .77% of the available fresh water accessible for human use. While wealthy countries may not feel this burden due to their infrastructure. Impoverish countries will feel the full burden of a lack of water. This has led to a growing number of water conflicts over the years some of which have resulted in human deaths. There are several ways that people can collect water from the atmosphere such as collecting rain water or using a solar still to evaporate water out of an undrinkable source. In parts of the world where fog is prevalent, meshes have been used to collect the moisture from the air. However, these systems only work where the environment allows for it. In some places in the world, the only amount of water may come from morning dew. Certain places receive more water from morning dew than they do from annual precipitation. By studying nature, a novel water collection device was developed, tested and modeled. The model is compared to the test data to see the ways in which the device can be optimized. This could be used to help alleviate the growing problems of water shortages in specific parts of the world. The model and device design shows promising data but still

  13. Investigation on the Energy Saving Potential of Using a Novel Dew Point Cooling System in Data Centres

    Directory of Open Access Journals (Sweden)

    Yin Bi

    2017-10-01

    Full Text Available Abstract: Information technology (IT has brought significant changes in people’s lives. As an important part of the IT industry, data centres (DCs have been rapidly growing in both the number and size over the past 40 years. Around 30% to 40% of electricity consumption in DCs is used for space cooling, thus leading to very inefficient DC operation. To identify ways to reduce the energy consumption for space cooling and increase the energy efficiency of DCs’ operation, a dedicated investigation into the energy usage in DCs has been undertaken and a novel high performance dew point cooling system was introduced into a DC operational scheme. Based on the cooling load in DCs, a case study was carried out to evaluate the energy consumptions and energy usage effectiveness when using the novel dew point cooling system in different scales of DCs in various climates. It was found that by using the novel dew point cooling system, for 10 typical climates a DC can have a much lower power usage effectiveness (PUE of 1.10 to 1.22 compared to that of 1.7 to 3.7 by using existing traditional cooling systems, leading to significantly increased energy efficiency of the DC operation. In addition, the energy performance by managing the cooling air supply at the different levels in DCs, i.e., room, row and rack level, was simulated by using a dynamic computer model. It was found that cooling air supply at rack level can provide a higher energy efficiency in DCs. Based on the above work, the energy saving potential in DCs was conducted by comparing DCs using an the novel dew point cooling system and the optimum management scheme for the cooling air supply to that using traditional air cooling systems and the same supply air management. Annual electricity consumptions for the two cases were given. It was found that by using the novel dew point cooling system and optimum management system for the cooling air supply, an 87.7~91.6% electricity consumption saving for

  14. Development of eggs and larvae of Emmelichthys nitidus (Percoidei: Emmelichthyidae) in south-eastern Australia, including a temperature-dependent egg incubation model

    Science.gov (United States)

    Neira, Francisco J.; Keane, John P.; Lyle, Jeremy M.; Tracey, Sean R.

    2008-08-01

    Reared eggs and field-collected material were employed to describe the development of the pelagic eggs and larvae of Emmelichthys nitidus (Emmelichthyidae), a small (36 cm TL) mid-water schooling species common in shelf waters of temperate Australia. Hydrated oocytes from adults trawled from spawning grounds off eastern Tasmania were fertilized and reared to the yolk-sac larval stage, and the data employed to build a temperature-dependent egg incubation model. Embryogenesis lasted 96, 84 and 54 h at mean temperatures of 13.1, 14.4 and 16.5 °C respectively, and was divided into seven stages based on extent of epiboly until blastopore closure (stages I-III) and embryo growth (stages IV-VII). Eggs (1.00-1.05 mm diameter) are spherical with a smooth chorion, small perivitelline space and prominent, unsegmented yolk with a single, posteriorly-located oil globule (0.18-0.20 mm diameter) that becomes pigmented from stage III. Embryos have two distinct snout melanophores, and a paired melanophore row laterally along the trunk and tail. Morphological identification of eggs collected during surveys in October 2005 and 2006 was validated using quantitative PCR amplification of the mtDNA d-loop gene region unique to E. nitidus, producing an 80-100% agreement across all seven stages. Newly-emerged larvae (1.9-3.3 mm) possess a prominent yolk sac with the posteriorly-located, pigmented oil globule, mouth not yet functional and unpigmented eyes. Notochord flexion occurs between 5 and 8 mm while fins are formed by 12 mm. Larvae examined (3.3-17.4 mm) are lightly pigmented and possess percoid features such as an elongate to moderate body, coiled, triangular-shaped gut, preopercular spines and 24-25 myomeres; two prominent pigment patches opposite each other dorsally and ventrally along the tail are diagnostic. Variability of mean egg ages ( y) by temperature ( t) and stage ( i) was best described by the deterministic stage-to-age model y = 35.911exp[-(0.155 t + 0.262 i)] i2

  15. Real-time monitoring of radiofrequency ablation of liver tumors using thermal-dose calculation by MR temperature imaging: initial results in nine patients, including follow-up

    International Nuclear Information System (INIS)

    Lepetit-Coiffe, Matthieu; Quesson, Bruno; Moonen, Chrit T.W.; Laumonier, Herve; Trillaud, Herve; Seror, Olivier; Sesay, Musa-Bahazid; Grenier, Nicolas

    2010-01-01

    To assess the practical feasibility and effectiveness of real-time magnetic resonance (MR) temperature monitoring for the radiofrequency (RF) ablation of liver tumours in a clinical setting, nine patients (aged 49-87 years, five men and four women) with one malignant tumour (14-50 mm, eight hepatocellular carcinomas and one colorectal metastasis), were treated by 12-min RF ablation using a 1.5-T closed magnet for real-time temperature monitoring. The clinical monopolar RF device was filtered at 64 MHz to avoid electromagnetic interference. Real-time computation of thermal-dose (TD) maps, based on Sapareto and Dewey's equation, was studied to determine its ability to provide a clear end-point of the RF procedure. Absence of local recurrence on follow-up MR images obtained 45 days after the RF ablation was used to assess the apoptotic and necrotic prediction obtained by real-time TD maps. Seven out of nine tumours were completely ablated according to the real-time TD maps. Compared with 45-day follow-up MR images, TD maps accurately predicted two primary treatment failures, but were not relevant in the later progression of one case of secondary local tumour. The real-time TD concept is a feasible and promising monitoring method for the RF ablation of liver tumours. (orig.)

  16. Real-time monitoring of radiofrequency ablation of liver tumors using thermal-dose calculation by MR temperature imaging: initial results in nine patients, including follow-up

    Energy Technology Data Exchange (ETDEWEB)

    Lepetit-Coiffe, Matthieu; Quesson, Bruno; Moonen, Chrit T.W. [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Laumonier, Herve; Trillaud, Herve [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Service de Radiologie, Hopital Saint-Andre, CHU Bordeaux, Bordeaux (France); Seror, Olivier [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Service de Radiologie, Hopital Jean Verdier, Bondy (France); Sesay, Musa-Bahazid [Service d' Anesthesie Reanimation III, Hopital Pellegrin, CHU Bordeaux, Bordeaux (France); Grenier, Nicolas [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Service d' Imagerie Diagnostique et Therapeutique de l' Adulte, Hopital Pellegrin, CHU Bordeaux, Bordeaux (France)

    2010-01-15

    To assess the practical feasibility and effectiveness of real-time magnetic resonance (MR) temperature monitoring for the radiofrequency (RF) ablation of liver tumours in a clinical setting, nine patients (aged 49-87 years, five men and four women) with one malignant tumour (14-50 mm, eight hepatocellular carcinomas and one colorectal metastasis), were treated by 12-min RF ablation using a 1.5-T closed magnet for real-time temperature monitoring. The clinical monopolar RF device was filtered at 64 MHz to avoid electromagnetic interference. Real-time computation of thermal-dose (TD) maps, based on Sapareto and Dewey's equation, was studied to determine its ability to provide a clear end-point of the RF procedure. Absence of local recurrence on follow-up MR images obtained 45 days after the RF ablation was used to assess the apoptotic and necrotic prediction obtained by real-time TD maps. Seven out of nine tumours were completely ablated according to the real-time TD maps. Compared with 45-day follow-up MR images, TD maps accurately predicted two primary treatment failures, but were not relevant in the later progression of one case of secondary local tumour. The real-time TD concept is a feasible and promising monitoring method for the RF ablation of liver tumours. (orig.)

  17. A 1D constitutive model for shape memory alloy using strain and temperature as control variables and including martensite reorientation and asymmetric behaviors

    International Nuclear Information System (INIS)

    Jaber, M Ben; Mehrez, S; Ghazouani, O

    2014-01-01

    In this paper, a new 1D constitutive model for shape memory alloy using strain and temperature as control variables is presented. The new formulation is restricted to the 1D stress case and takes into account the martensite reorientation and the asymmetry of the SMA behavior in tension and compression. Numerical implementation of the new model in a finite element code was conducted. The numerical results for superelastic behavior in tension and compression tests are presented and were compared to experimental data taken from the literature. Other numerical tests are presented, showing the model’s ability to reproduce the main aspects of SMA behavior such as the shape memory effect and the martensite reorientation under cyclic loading. Finally, to demonstrate the utility of the new constitutive model, a dynamic test of a bi-clamped SMA bending beam under forced oscillation is described. (paper)

  18. UV-photodegradation of desipramine: Impact of concentration, pH and temperature on formation of products including their biodegradability and toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Khaleel, Nareman D.H.; Mahmoud, Waleed M.M. [Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Leuphana University of Lüneburg, Scharnhorststraße 1 C13, DE 21335 Lüneburg (Germany); Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Suez Canal University, Ismailia 41522 (Egypt); Olsson, Oliver [Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Leuphana University of Lüneburg, Scharnhorststraße 1 C13, DE 21335 Lüneburg (Germany); Kümmerer, Klaus, E-mail: klaus.kuemmerer@leuphana.de [Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Leuphana University of Lüneburg, Scharnhorststraße 1 C13, DE 21335 Lüneburg (Germany)

    2016-10-01

    Desipramine (DMI) is a widely used tricyclic antidepressant, and it is the major metabolite of imipramine (IMI) and lofepramine (LMI); IMI and LMI are two of the most commonly used tricyclic antidepressants. If DMI enters the aquatic environment, it can be transformed by the environmental bacteria or UV radiation. Therefore, photolysis of DMI in water was performed using a simulated sunlight Xenon-lamp and a UV-lamp. Subsequently, the biodegradability of DMI and its photo-transformation products (PTPs) formed during its UV photolysis was studied. The influence of variable conditions, such as initial DMI concentration, solution pH, and temperature, on DMI UV photolysis behavior was also studied. The degree of mineralization of DMI and its PTPs was monitored. A Shimadzu HPLC-UV apparatus was used to follow the kinetic profile of DMI during UV-irradiation; after that, ion-trap and high-resolution mass spectrometry coupled with chromatography were used to monitor and identify the possible PTPs. The environmentally relevant properties and selected toxicity properties of DMI and the non-biodegradable PTPs were predicted using different QSAR models. DMI underwent UV photolysis with first-order kinetics. Quantum yields were very low. DOC values indicated that DMI formed new PTPs and was not completely mineralized. Analysis by means of high-resolution mass spectrometry revealed that the photolysis of DMI followed three main photolysis pathways: isomerization, hydroxylation, and ring opening. The photolysis rate was inversely proportional to initial DMI concentration. The pH showed a significant impact on the photolysis rate of DMI, and on the PTPs in terms of both formation kinetics and mechanisms. Although temperature was expected to increase the photolysis rate, it showed a non-significant impact in this study. Results from biodegradation tests and QSAR analysis revealed that DMI and its PTPs are not readily biodegradable and that some PTPs may be human and/or eco

  19. The effect of environmental humidity and temperature on skin barrier function and dermatitis

    DEFF Research Database (Denmark)

    Engebretsen, K A; Johansen, J D; Kezic, S

    2016-01-01

    existing dermatoses. We searched the literature for studies that evaluated the mechanisms behind this phenomenon. Commonly used meteorological terms such as absolute humidity, relative humidity and dew point are explained. Furthermore, we review the negative effect of low humidity, low temperatures...

  20. Effect of Different Growth Stages and Dew Period Length on Disease Development of Alternaria alternata as a Biological Control Agent for Convolvulus arvensis

    Directory of Open Access Journals (Sweden)

    E Zeidali

    2012-02-01

    Full Text Available Abstract Field bindweed is an important perinial weed of agricultural crops word-wide. There are plant pathogen fungus which could cause necrotic spots on the leaves and stems of convolvulus arvensis under natural coditions. In order to evaluate the effects of weed growth stage and length of dew period on disease development causes by Aletrnaria alternata and Fusarium sp. two expriments were performed in the greenhouse based on a completely randomized design in factorial arrangement with four replications during 2006-2007. Spore concentration for both experiments was 107 spores per ml of distilled water. In the first experiment, treatments were different growth stages of field bindweed (cotyledon, 4-leaf, 6-leaf, 9-11-leaf stages. Results showed that disease development in the fungus of A. alternata was higher than Fusarium sp. The most susceptable growth stage of field bindweed plants to A. alternata was 2-4-leave stage. The second expriment was performed in order to study the effect of dew period length (6, 12, 24 and 48 hour dew periods on disease development at 4-leaf growth stage of field bindweed. The maximum disease development and minimum weed dry weight were observed with application of the fungus of A. alternata at dew periods of 24 and 48 hour, however, plant damage was also observed with a length of 6 hours dew period.

  1. Study Modules for Calculus-Based General Physics. [Includes Modules 18-20: Sound; Temperature, Heat, and Thermodynamics: First Law; and Kinetic Theory of Gases].

    Science.gov (United States)

    Fuller, Robert G., Ed.; And Others

    This is part of a series of 42 Calculus Based Physics (CBP) modules totaling about 1,000 pages. The modules include study guides, practice tests, and mastery tests for a full-year individualized course in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…

  2. EPR spectroscopy of MRI-related Gd(III) complexes: simultaneous analysis of multiple frequency and temperature spectra, including static and transient crystal field effects.

    Science.gov (United States)

    Rast, S; Borel, A; Helm, L; Belorizky, E; Fries, P H; Merbach, A E

    2001-03-21

    For the first time, a very general theoretical method is proposed to interpret the full electron paramagnetic resonance (EPR) spectra at multiple temperatures and frequencies in the important case of S-state metal ions complexed in liquid solution. This method is illustrated by a careful analysis of the measured spectra of two Gd3+ (S = 7/2) complexes. It is shown that the electronic relaxation mechanisms at the origin of the EPR line shape arise from the combined effects of the modulation of the static crystal field by the random Brownian rotation of the complex and of the transient zero-field splitting. A detailed study of the static crystal field mechanism shows that, contrarily to the usual global models involving only second-order terms, the fourth and sixth order terms can play a non-negligible role. The obtained parameters are well interpreted in the framework of the physics of the various underlying relaxation processes. A better understanding of these mechanisms is highly valuable since they partly control the efficiency of paramagnetic metal ions in contrast agents for medical magnetic resonance imaging (MRI).

  3. Design of the low-temperature rectification plant KRETA including the pre-purification units ADAMO and REDUKTION and first operating experience

    International Nuclear Information System (INIS)

    Ammon, R. v.; Hutter, E.; Leichsenring, C.H.; Weinlaender, W.

    1977-01-01

    In the off-gas treatment system developed by the GfK Karlsruhe the noble gases Kr and Xe are removed by means of a low-temperature rectification process, in which the Kr-85 is largely separated from the inactive Xe. The Xe can then be released to the environment, while the radioactive Kr must be stored in steel cylinders. Prior to the above treatment the oxygen is removed to minimize ozone formation. This is effected, together with the removal of residual oxides of nitrogen, by catalytic reduction with hydrogen. At a subsequent stage of the pre-purification process all the gaseous components which could freeze out in the cryogenic section, i.e. H 2 O, CO 2 and NH 3 , and are removed by adsorption. These stages of the process are being investigated in the reduced-scale KRETA, REDUKTION and ADAMO pilot plants, which have a gas through-put of 50 m 3 /h (at N.T.P.), using simulated inactive gas mixtures. The design of the three plants is described. The initial tests on the KRETA plant showed that an experimental decontamination factor of >= 10 3 could be achieved for the first column for rectification of the N 2 -Kr-Xe system. Instances of xenon freezing out were also observed, these being accompanied by a drop in the decontamination factor. Separation of Kr from Xe in the second column proceeded smoothly with high enrichment of both components. Both the capacity and the efficiency of the ADAMO plant are very high for the separat ion of H 2 O and CO 2 . Coadsorbed Kr can be fully desorbed under normal conditions by flushing with N 2 . Following preliminary laboratory tests for the REDUKTION plant a ruthenium catalyst has been selected, which is particularly insensitive to poisoning, e.g. by iodine. (orig./ORU) [de

  4. Application of model MTS5 dew-point meter in gas sampling and analyzing system of HTR-10

    International Nuclear Information System (INIS)

    Zhu Jiang; Li Zhihui

    2010-01-01

    The feature of humidity detector to measure the content of water in pure helium of main loop of reactor was discussed, and the circumstances using Al 2 O 3 moisture sensor to measure the content of water in helium on-line were introduced. During those few years, the dew-point meter has sufficed to measure the content of water in the helium gas during the running of the reactor. On the other hand, excursion can happen when the instrument running. Demarcate must be made periodically to improve the veracity of the meter. (authors)

  5. Experimental investigation of carbon monoxide poisoning effect on a PBI/H3PO4 high temperature polymer electrolyte membrane fuel cell

    DEFF Research Database (Denmark)

    Zhou, Fan; Andreasen, Søren Juhl; Kær, Søren Knudsen

    2015-01-01

    humidity level reduced the cell performance loss caused by CO poisoning. When the fuel cell was operated with pure H2, the cell performance was not significantly affect by the change in anode dew point temperature in the range of room temperature and 60 °C. CO2 in anode stream resulted in slight decrease...

  6. Data set: 31 years of spatially distributed air temperature, humidity, precipitation amount and precipitation phase from a mountain catchment in the rain-snow transition zone

    Science.gov (United States)

    Thirty one years of spatially distributed air temperature, relative humidity, dew point temperature, precipitation amount, and precipitation phase data are presented for the Reynolds Creek Experimental Watershed. The data are spatially distributed over a 10m Lidar-derived digital elevation model at ...

  7. [Comparison of ability to humidification of inspired air through the nose and oral cavity using dew point hygrometer].

    Science.gov (United States)

    Paczesny, Daniel; Rapiejko, Piotr; Weremczuk, Jerzy; Jachowicz, Ryszard; Jurkiewicz, Dariusz

    2007-01-01

    Aim of this study was to check at the hospital the dew point hygrometer for fast measurement of air humidity in upper airways. The nose ability to humidification of inspired air and partially recover moisture from expired air was evaluated. Measurements from respiration through the nose and oral cavity were compared. The study was carried out in a group of 30 people (8 female and 22 male), age group 18 to 70 (mean age: 37 years old). In 22 of the participants there were no deviation from normal state in laryngologic examination, while in 4 participants nasal septum deviation without imaired nasal; oatency was found, in other 3--nasal vonchae hyperthrophy and in 1--nasal polips (grade I). The measurements of air humidity in upper air ways was done using specially designed and constructed measurement system. The air inspired through the nose and oral cavity is humidified. For typical external conditions (T = 22 degrees C i RH = 50%) the nose humidifies inspired air two times better then oral cavity (short time range of measurement approximately 1 min). Moisture from expired air through the nose is partially recovered (for patients with regular patency is 25% of the value of humidifying of inspired air). The oral cavity does not have ability to partially recovery moisture form expired air. The paper presented fast dew point hygrometer based on semiconductor microsystems for measurement humidity in inspired and expired air through the nose and oral cavity. Presented system can be a proper instrument for evaluation of nasal functions.

  8. Energy Balance, Evapo-transpiration and Dew deposition in the Dead Sea Valley

    Science.gov (United States)

    Metzger, Jutta; Corsmeier, Ulrich

    2016-04-01

    The Dead Sea is a unique place on earth. It is a terminal hypersaline lake, located at the lowest point on earth with a lake level of currently -429 m above mean sea level (amsl). It is located in a transition zone of semiarid to arid climate conditions, which makes it highly sensible to climate change (Alpert1997, Smiatek2011). The Virtual Institute DEad SEa Research Venue (DESERVE) is an international project funded by the German Helmholtz Association and was established to study coupled atmospheric hydrological, and lithospheric processes in the changing environment of the Dead Sea. At the moment the most prominent environmental change is the lake level decline of approximately 1 m / year due to anthropogenic interferences (Gertman, 2002). This leads to noticeable changes in the fractions of the existing terrestrial surfaces - water, bare soil and vegetated areas - in the valley. Thus, the partitioning of the net radiation in the valley changes as well. To thoroughly study the atmospheric and hydrological processes in the Dead Sea valley, which are driven by the energy balance components, sound data of the energy fluxes of the different surfaces are necessary. Before DESERVE no long-term monitoring network simultaneously measuring the energy balance components of the different surfaces in the Dead Sea valley was available. Therefore, three energy balance stations were installed at three characteristic sites at the coast-line, over bare soil, and within vegetation, measuring all energy balance components by using the eddy covariance method. The results show, that the partitioning of the energy into sensible and latent heat flux on a diurnal scale is totally different at the three sites. This results in gradients between the sites, which are e.g. responsible for the typical diurnal wind systems at the Dead Sea. Furthermore, driving forces of evapo-transpiration at the sites were identified and a detailed analysis of the daily evaporation and dew deposition rates

  9. Acoustic dew point and bubble point detector for gas condensates and reservoir fluids

    Energy Technology Data Exchange (ETDEWEB)

    Sivaraman, A.; Hu, Y.; Thomas, F. B.; Bennion, D. B.; Jamaluddin, A. K. M. [Hycal Energy Research Labs. Ltd., Calgary, AB (Canada)

    1997-08-01

    Detailed knowledge of bubblepoint and dewpoint pressures at reservoir temperature are crucial for natural gas processing, transportation, metering and utilization. This paper introduces a new acoustic dewpoint and bubblepoint detector that can be applied to a broad range of phase transitions, including very lean gas systems and opaque heavy oils. The system uses two acoustic transducers, one to stimulate and the other to detect normal mode vibrations of reservoir fluids in a small cylindrical resonator. The acoustic spectra are recorded at close intervals throughout the phase envelope, along with temperature, pressure and volume measurements, and the data is processed to obtain the specific condition of phase transition. Results of two systems, a binary mixture and live reservoir fluid, are presented. The detector system is claimed to be capable of operation in an isothermal mode with variable volume, and in a constant volume mode with variable temperatures. Interpretation of results is free of operator subjectivity; they show excellent agreement with results obtained by visual methods and equations of state calculations. 4 refs., 2 tabs., 4 figs.

  10. Automated calibration of laser spectrometer measurements of δ18 O and δ2 H values in water vapour using a Dew Point Generator.

    Science.gov (United States)

    Munksgaard, Niels C; Cheesman, Alexander W; Gray-Spence, Andrew; Cernusak, Lucas A; Bird, Michael I

    2018-06-30

    Continuous measurement of stable O and H isotope compositions in water vapour requires automated calibration for remote field deployments. We developed a new low-cost device for calibration of both water vapour mole fraction and isotope composition. We coupled a commercially available dew point generator (DPG) to a laser spectrometer and developed hardware for water and air handling along with software for automated operation and data processing. We characterised isotopic fractionation in the DPG, conducted a field test and assessed the influence of critical parameters on the performance of the device. An analysis time of 1 hour was sufficient to achieve memory-free analysis of two water vapour standards and the δ 18 O and δ 2 H values were found to be independent of water vapour concentration over a range of ≈20,000-33,000 ppm. The reproducibility of the standard vapours over a 10-day period was better than 0.14 ‰ and 0.75 ‰ for δ 18 O and δ 2 H values, respectively (1 σ, n = 11) prior to drift correction and calibration. The analytical accuracy was confirmed by the analysis of a third independent vapour standard. The DPG distillation process requires that isotope calibration takes account of DPG temperature, analysis time, injected water volume and air flow rate. The automated calibration system provides high accuracy and precision and is a robust, cost-effective option for long-term field measurements of water vapour isotopes. The necessary modifications to the DPG are minor and easily reversible. Copyright © 2018 John Wiley & Sons, Ltd.

  11. Searching for the best modeling specification for assessing the effects of temperature and humidity on health: a time series analysis in three European cities.

    Science.gov (United States)

    Rodopoulou, Sophia; Samoli, Evangelia; Analitis, Antonis; Atkinson, Richard W; de'Donato, Francesca K; Katsouyanni, Klea

    2015-11-01

    Epidemiological time series studies suggest daily temperature and humidity are associated with adverse health effects including increased mortality and hospital admissions. However, there is no consensus over which metric or lag best describes the relationships. We investigated which temperature and humidity model specification most adequately predicted mortality in three large European cities. Daily counts of all-cause mortality, minimum, maximum and mean temperature and relative humidity and apparent temperature (a composite measure of ambient and dew point temperature) were assembled for Athens, London, and Rome for 6 years between 1999 and 2005. City-specific Poisson regression models were fitted separately for warm (April-September) and cold (October-March) periods adjusting for seasonality, air pollution, and public holidays. We investigated goodness of model fit for each metric for delayed effects up to 13 days using three model fit criteria: sum of the partial autocorrelation function, AIC, and GCV. No uniformly best index for all cities and seasonal periods was observed. The effects of temperature were uniformly shown to be more prolonged during cold periods and the majority of models suggested separate temperature and humidity variables performed better than apparent temperature in predicting mortality. Our study suggests that the nature of the effects of temperature and humidity on mortality vary between cities for unknown reasons which require further investigation but may relate to city-specific population, socioeconomic, and environmental characteristics. This may have consequences on epidemiological studies and local temperature-related warning systems.

  12. Nowcasting Surface Meteorological Parameters Using Successive Correction Method

    National Research Council Canada - National Science Library

    Henmi, Teizi

    2002-01-01

    The successive correction method was examined and evaluated statistically as a nowcasting method for surface meteorological parameters including temperature, dew point temperature, and horizontal wind vector components...

  13. EFFECT OF DEW POINT OF ATMOSPHERE OF CGL’S ANNEALING FURNACES ON THE QUALITY OF GA COATING ON BAKE HARDENABLE STEEL

    Directory of Open Access Journals (Sweden)

    Juliana Porto Guimarães

    2013-10-01

    Full Text Available The strip steel surface condition after continuous annealing of strip is extremely important to the quality of galvannealed coating (GA. The presence of oxides or precipitated can affect the reactions at the coating/substrate interface and decrease the zinc wettability on the steel surface, leading to various defects in the final product. To avoid oxidation of the material during continuous annealing, a protective atmosphere is used in the furnaces. Despite this atmosphere, it is possible the selective oxidation or precipitation of second phase particles, being the dew point of atmosphere one of the leading factors to reduce this occurrence. This study aims to evaluate the effect of the dew point on the quality of GA coatings applied to a bake hardenable steel. The continuous annealing under dew points of –60°C, 30°C and 0°C, as well as hot dip galvanizing, were performed in a Hot Dip Process Simulator. It is found that the dew point has a decisive influence on the amount, distribution and type of oxides formed, and the condition of –30°C provided the coating with less failures and better adhesion.

  14. The Mollier diagram in theory and practice. Part 3. Examples on Calculation of Dew Point Cooling; Het Mollierdiagram in theorie en praktijk. Deel 3. Rekenvoorbeelden Dauwpuntkoeling

    Energy Technology Data Exchange (ETDEWEB)

    Kouwenhoven, H.J.L. [Frigidarium, Driebergen-Rijsenburg (Netherlands); Huizinga, H.T. [Heat Transfer Holland HTH, Zuidwolde (Netherlands); Bootsveld, N.R. [YNO, Delft (Netherlands); Janssen, M. [Re-gent, Helmond (Netherlands); Uges, P.G.H. [StatiqCooling, Deventer (Netherlands)

    2007-04-15

    The use of direct and indirect adiabatic cooling, and recently in particular indirect diabatic cooling (dew point cooling) require knowledge of the Mollier diagram. [Dutch] Het gebruik van direct en indirect werkende adiabatische koeling en recentlijk vooral de indirect werkende systemen zoals diabatische koeling (dauwpuntkoeling, al of niet uitgevoerd als statische koeling) vragen om kennis van het Mollierdiagram.

  15. Delivery of State-Provided Predictive Analytics to Schools: Wisconsin's DEWS and the Proposed EWIMS Dashboard. WCER Working Paper No. 2016-3

    Science.gov (United States)

    Clune, Bill; Knowles, Jared

    2016-01-01

    Since 2012, the Wisconsin Department of Public Instruction (DPI) has maintained a statewide predictive analytics system providing schools with an early warning in middle grades of students at risk for not completing high school. DPI is considering extending and enhancing this system, known as the Dropout Early Warning System (DEWS). The proposed…

  16. Modeling of atmospheric corrosion environments and its application to constant dew-point corrosion test; Yagai taiki fushoku kankyo no modeling to sore ni motozuku teirotengata saikuru fushoku shikenho no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Muto, I. [Nippon Steel Corp., Tokyo (Japan)] Sugimoto, K. [Tohoku Univ., Sendai (Japan)

    1998-08-15

    Recently, stainless steel is increasing its demand for corrosion resistant building materials. Then, as it is necessary to develop and accelerating testing method capable of accurately estimating weatherability at sea side area, such testing method has no been developed yet because of difficulty to quantify corrosive environment relating to atmospheric corrosion phenomenon. As air temperature and relative humidity in outdoor change in complex, specific temperature and relative humidity cannot be used for their representative values. And, construction of corrosive factors such as sea salt particles, and so on are also much different at each area. However, at coastal area, a dew water dissolving the sea salt particles, so called droplets of chlorides aqueous solution is formed onto material surface. Then, in this study, on a base of drying and humidity absorption behavior and daily change behavior of temperature and humidity in outdoor, modeling of atmospheric corrosion environment was tried. An accelerating testing method according to this modeling was developed, long-term weathering test was compared with the corrosion behavior of the same steel, and validity of a new accelerating testing method was evaluated. 22 refs., 12 figs., 2 tabs.

  17. Determination of equilibrium phase composition in the Hg-HgTe-CdTe system by ''dew point'' method

    International Nuclear Information System (INIS)

    Vanyukov, A.V.; Krotov, I.I.; Ermakov, A.I.

    1978-01-01

    Using the ''dew point'' method a study has been made of the equilibrium composition of the solid and liquid phases in the Hg-HgTe-CdTe system at 404, 435 and 454 deg C. It has been pointed out that crystallization of cadmium-rich solid solutions of Cdsub(x)Hgsub(1-x) Te takes place from a liquid phase with a much higher concentration of Hg. The activity of Hg in the liquid phase increases along the liquidus isotherm in the direction from section Hg-HgTe to section HgCdTe in accordance with the increase of its concentration. An increase in activity of Hg in the solid phase of Cdsub(x)Hgsub(1-x)Te has been noted with the reduction of its concentration

  18. Thermodynamic analysis of high-temperature regenerative organic Rankine cycles using siloxanes as working fluids

    International Nuclear Information System (INIS)

    Fernandez, F.J.; Prieto, M.M.; Suarez, I.

    2011-01-01

    A recent novel adjustment of the Span-Wagner equation of state for siloxanes, used as working fluids in high-temperature organic Rankine cycles, is applied in a mathematical model to solve cycles under several working conditions. The proposed scheme includes a thermo-oil intermediate heat circuit between the heat source and the organic Rankine cycle. Linear and cyclic siloxanes are assayed in saturated, superheated and supercritical cycles. The cycle includes an internal heat exchanger (regenerative cycle), although a non-regenerative scheme is also solved. In the first part of the study, a current of combustion gases cooled to close to their dew point temperature is taken as the reference heat source. In the second part, the outlet temperature of the heat source is varied over a wide range, determining appropriate fluids and schemes for each thermal level. Simple linear (MM, MDM) siloxanes in saturated regenerative schemes show good efficiencies and ensure thermal stability of the working fluid. -- Highlights: → Organic Rankine cycles with polymethylsiloxanes as working fluids were modelled. → The cycle scheme is regenerative and includes an intermediate heat transfer fluid. → The fluid properties were calculated by means of the Span-Wagner equation of state. → Vapour conditions to the expander and source thermal level were analysed. → Siloxanes MM, MDM and D 4 under saturated conditions were the best options.

  19. Influence of Gas Atmosphere Dew Point on the Selective Oxidation and the Reactive Wetting During Hot Dip Galvanizing of CMnSi TRIP Steel

    Science.gov (United States)

    Cho, Lawrence; Lee, Seok Jae; Kim, Myung Soo; Kim, Young Ha; De Cooman, Bruno C.

    2013-01-01

    The selective oxidation and reactive wetting of intercritically annealed Si-bearing CMnSi transformation-induced plasticity steels were investigated by high-resolution transmission electron microscopy. In a N2 + 10 pct H2 gas atmosphere with a dew point (DP) ranging from 213 K to 278 K (-60 °C to 5 °C), a continuous layer of selective oxides was formed on the surface. Annealing in a higher DP gas atmosphere resulted in a thinner layer of external oxidation and a greater depth of internal oxidation. The hot dipping was carried out in a Zn bath containing 0.22 mass pct Al, and the bath temperature was 733 K (460 °C). Coarse and discontinuous Fe2Al5- x Zn x grains and Fe-Zn intermetallics (ζ and δ) were observed at the steel/coating interface after the hot dip galvanizing (HDG) of panels were annealed in a low DP atmosphere 213 K (-60 °C). The Fe-Zn intermetallics were formed both in areas where the Fe2Al5- x Zn x inhibition layer had not been formed and on top of non-stoichiometric Fe-Al-Zn crystals. Poor wetting was observed on panels annealed in a low DP atmosphere because of the formation of thick film-type oxides on the surface. After annealing in higher DP gas atmospheres, i.e., 263 K and 278 K (-10 °C and 5 °C), a continuous and fine-grained Fe2Al5- x Zn x layer was formed. No Fe-Zn intermetallics were formed. The small grain size of the inhibition layer was attributed to the nucleation of the Fe2Al5- x Zn x grains on small ferrite sub-surface grains and the presence of granular surface oxides. A high DP atmosphere can therefore significantly contribute to the decrease of Zn-coating defects on CMnSi TRIP steels processed in HDG lines.

  20. Filter for underground mining for suction of preferably full cut and part cut machines, to be provided with preheated air, to avoid dropping below the dew point

    Energy Technology Data Exchange (ETDEWEB)

    Hoelter, H.

    1976-10-28

    Particularly when cutting hard rock, the cutting room to be provided with suction is wetted with water from nozzles, which, when sucking out air containing dust with high humidity leads to encrustation in the filter cloth. In order to avoid this, it is proposed that the air should be heated, using heat from the motor driving the ventilator, so that one avoids dropping below the dew point in the filter.

  1. Test and evaluation of a method of utilizing flue gas below the dew point

    Energy Technology Data Exchange (ETDEWEB)

    Wilsdorf, J.; Mueller, R.

    1983-09-01

    Technological possibilities of using power plant waste heat for low temperature heating of buildings or for industrial heat supply are discussed. Waste heat is recovered with a water circulating heat exchanger to a degree of 15%. Diagrams are presented for a hot water supply system at conventional power generators of 600 to 2,500 kW. Heat balances for a small steam generator of 800 kg/h steam capacity are calculated, comparing the energy efficiency with and without low temperature heat recovery systems. Economic benefits, which can be realized with waste heat recovery systems are calculated. 8 references.

  2. Uncertainty Evaluation of the New Setup for Measurement of Water-Vapor Permeation Rate by a Dew-Point Sensor

    Science.gov (United States)

    Hudoklin, D.; Šetina, J.; Drnovšek, J.

    2012-09-01

    The measurement of the water-vapor permeation rate (WVPR) through materials is very important in many industrial applications such as the development of new fabrics and construction materials, in the semiconductor industry, packaging, vacuum techniques, etc. The demand for this kind of measurement grows considerably and thus many different methods for measuring the WVPR are developed and standardized within numerous national and international standards. However, comparison of existing methods shows a low level of mutual agreement. The objective of this paper is to demonstrate the necessary uncertainty evaluation for WVPR measurements, so as to provide a basis for development of a corresponding reference measurement standard. This paper presents a specially developed measurement setup, which employs a precision dew-point sensor for WVPR measurements on specimens of different shapes. The paper also presents a physical model, which tries to account for both dynamic and quasi-static methods, the common types of WVPR measurements referred to in standards and scientific publications. An uncertainty evaluation carried out according to the ISO/IEC guide to the expression of uncertainty in measurement (GUM) shows the relative expanded ( k = 2) uncertainty to be 3.0 % for WVPR of 6.71 mg . h-1 (corresponding to permeance of 30.4 mg . m-2. day-1 . hPa-1).

  3. Unsteady-state analysis of a counter-flow dew point evaporative cooling system

    KAUST Repository

    Lin, J.; Thu, K.; Bui, T.D.; Wang, R.Z.; Ng, Kim Choon; Kumja, M.; Chua, K.J.

    2016-01-01

    temperature, humidity and velocity; (2) the settling time of the transient response ranges from 50 s to 300 s when the system operates under different inlet conditions; and (3) the average transient wet bulb effectiveness (1.00–1.06) of the system is observed

  4. Influência do orvalho e volume de calda de aplicação na eficácia do glyphosate na dessecação de Brachiaria plantaginea Influence of dew and spray volume on the efficacy of glyphosate for Brachiaria plantaginea burndown

    Directory of Open Access Journals (Sweden)

    E.S. Roman

    2004-09-01

    Full Text Available A eficácia de herbicidas é influenciada por diversos fatores que afetam a absorção e a translocação desses compostos na planta. A absorção de herbicidas pelas plantas, por exemplo, é influenciada, tanto física como biologicamente, pela temperatura e pela umidade relativa do ar dentro do dossel. Com a diminuição da umidade relativa do ar e/ou com o aumento da temperatura, as gotas da pulverização secam mais rapidamente e a absorção do produto diminui, ou até mesmo cessa, afetando o desempenho biológico. Com base nessa premissa, o presente estudo teve como objetivo examinar a influência do orvalho e do volume de calda de aplicação na eficiência de doses de glyphosate para o controle de Brachiaria plantaginea. Foram observadas interações significativas entre volume de calda, orvalho e dose de glyphosate. O volume mais baixo (100 L ha-1 resultou em melhor controle da espécie, especialmente quando o herbicida foi usado na menor dose (90 g ha-1. A presença de orvalho nas folhas causou reduções na atividade do produto, especialmente quando aplicado na menor dose e combinado com maior volume de calda.The efficacy of herbicides is influenced by several factors affecting the absorption and translocation of these compounds in the plant. Herbicide plant absorption, for example, is both physically and biologically influenced by temperature and air relative humidity in the plant canopy. With the reduction in relative air humidity and/or increase in temperature, the spray droplets dry more rapidly and the absorption of the herbicide decreases or even stops, affecting the biological performance. Based on that, this research aimed to study the influence of dew and spray volume on the efficacy of glyphosate rates in the control of B. plantaginea. There were significant interactions among volume of water, dew and rate of glyphosate. The lower the water volume, the more effective the glyphosate activity was, especially when applied at

  5. Numerical investigation of the energy performance of a guideless irregular heat and mass exchanger with corrugated heat transfer surface for dew point cooling

    International Nuclear Information System (INIS)

    Xu, Peng; Ma, Xiaoli; Diallo, Thierno M.O.; Zhao, Xudong; Fancey, Kevin; Li, Deying; Chen, Hongbing

    2016-01-01

    The paper presents an investigation into the energy performance of a novel irregular heat and mass exchanger for dew point cooling which, compared to the existing flat-plate heat exchangers, removed the use of the channel supporting guides and implemented the corrugated heat transfer surface, thus expecting to achieve the reduced air flow resistance, increased heat transfer area, and improved energy efficiency (i.e. Coefficient of Performance (COP)) of the air cooling process. CFD simulation was carried out to determine the flow resistance (K) factors of various elements within the dry and wet channels of the exchanger, while the ‘finite-element’ based ‘Newton-iteration’ numerical simulation was undertaken to investigate its cooling capacity, cooling effectiveness and COP at various geometrical and operational conditions. Compared to the existing flat-plate heat and mass exchangers with the same geometrical dimensions and operational conditions, the new irregular exchanger could achieve 32.9%–37% higher cooling capacity, dew-point and wet-bulb effectiveness, 29.7%–33.3% higher COP, and 55.8%–56.2% lower pressure drop. While undertaking dew point air cooling, the irregular heat and mass exchanger had the optimum air velocity of 1 m/s within the flow channels and working-to-intake air ratio of 0.3, which allowed the highest cooling capacity and COP to be achieved. In terms of the exchanger dimensions, the optimum height of the channel was 5 mm while its length was in the range 1–2 m. Overall, the proposed irregular heat and mass exchanger could lead to significant enhanced energy performance compared to the existing flat-plate dew point cooling heat exchanger of the same geometrical dimensions. To achieve the same amount cooling output, the irregular heat and mass exchanger had the reduced size and cost against the flat-plate ones. - Highlights: • Numerical investigation of an irregular heat and mass exchanger was undertaken. • A

  6. Selective Oxidation of a 0.1C-6Mn-2Si Third Generation Advanced High-Strength Steel During Dew-Point Controlled Annealing

    Science.gov (United States)

    Pourmajidian, Maedeh; McDermid, Joseph R.

    2018-03-01

    The present study investigates the selective oxidation of a 0.1C-6Mn-2Si medium-Mn advanced high-strength steel during austenization annealing heat treatments as a function of process atmosphere oxygen partial pressure and annealing time. It was determined that the surface oxide growth kinetics followed a parabolic rate law with the minimum rate belonging to the lowest oxygen partial pressure atmosphere at a dew point of 223 K (- 50 °C). The chemistry of the surface and subsurface oxides was studied using STEM + EELS on the sample cross sections, and it was found that the surface oxides formed under the 223 K (- 50 °C) dew-point atmosphere consisted of a layered configuration of SiO2, MnSiO3, and MnO, while in the case of the higher pO2 process atmospheres, only MnO was detected at the surface. Consistent with the Wagner calculations, it was shown that the transition to internal oxidation for Mn occurred under the 243 K (- 30 °C) and 278 K (+ 5 °C) dew-point atmospheres. However, the predictions of the external to internal oxidation for Si using the Wagner model did not correlate well with the experimental findings nor did the predictions of the Mataigne et al. model for multi-element alloys. Investigations of the internal oxide network at the grain boundaries revealed a multilayer oxide structure composed of amorphous SiO2 and crystalline MnSiO3, respectively, at the oxide core and outer shell. A mechanism for the formation of the oxide morphologies observed, based on kinetic and thermodynamic factors, was proposed. It is expected that only the fine and nodule-like MnO oxides formed on the surface of the samples annealed under the 278 K (+ 5 °C) dew-point process atmosphere for 60 and 120 seconds are sufficiently thin and of the desired dispersed morphology to promote reactive wetting by the molten galvanizing bath.

  7. Dew drops on spider web appearance: a newly named pattern of IgG4 deposition in pemphigus with direct immunofluorescence

    Directory of Open Access Journals (Sweden)

    Marian Dmochowski

    2017-08-01

    Full Text Available Novel appearances in cutaneous pathology as well as mucocutaneous clinical signs are being described which indicate that this is still an attractive area for exploration. The H + E histology terms of “decorated tomb stoning” and “undecorated tomb stoning”, advocated by some pathologists, are misleading and as such should be avoided. Here, an appearance of IgG4 pemphigus deposits examined cost-effectively with direct immunofluorescence and suggested to be called “dew drops on spider web” is depicted in depth.

  8. Prestressed concrete reactor vessel for the HHT-670 MW(e) demonstration plant. Pt.2. Three-dimensional analysis of the temperature and stress fields in a HHT vessel, including effects of the thermal creep

    International Nuclear Information System (INIS)

    Rodriguez, C.; Rebora, B.

    1979-01-01

    The thermal rheological calculation of the prestressed concrete reactor vessel for the HHT-670 MW(e) Demonstration Plant is presented in the paper. The main aim of this calculation is to evaluate the effects of the elevated temperature and various loads on the liner as well as on the hot concrete

  9. The effects of different nano particles of Al2O3 and Ag on the MHD nano fluid flow and heat transfer in a microchannel including slip velocity and temperature jump

    Science.gov (United States)

    Karimipour, Arash; D'Orazio, Annunziata; Shadloo, Mostafa Safdari

    2017-02-01

    The forced convection of nanofluid flow in a long microchannel is studied numerically according to the finite volume approach and by using a developed computer code. Microchannel domain is under the influence of a magnetic field with uniform strength. The hot inlet nanofluid is cooled by the heat exchange with the cold microchannel walls. Different types of nanoparticles such as Al2O3 and Ag are examined while the base fluid is considered as water. Reynolds number are chosen as Re=10 and Re=100. Slip velocity and temperature jump boundary conditions are simulated along the microchannel walls at different values of slip coefficient for different amounts of Hartmann number. The investigation of magnetic field effect on slip velocity and temperature jump of nanofluid is presented for the first time. The results are shown as streamlines and isotherms; moreover the profiles of slip velocity and temperature jump are drawn. It is observed that more slip coefficient corresponds to less Nusselt number and more slip velocity especially at larger Hartmann number. It is recommended to use Al2O3-water nanofluid instead of Ag-water to increase the heat transfer rate from the microchannel walls at low values of Re. However at larger amounts of Re, the nanofluid composed of nanoparticles with higher thermal conductivity works better.

  10. The Mollier diagram in theory and practice. Part 2. Evaporative indirect static dew point cooling and the Mollier diagram; Het Mollierdiagram in theorie en praktijk. Deel 2. Verdampingskoeling verklaard vanuit het Mollierdiagram

    Energy Technology Data Exchange (ETDEWEB)

    Uges, P.G.H. (ed.) [StatiqCooling, Deventer (Netherlands)

    2007-02-15

    The use of direct and indirect adiabatic cooling, and recently in particular indirect diabatic cooling (dew point cooling) require knowledge of the Mollier diagram. [Dutch] Het gebruik van direct en indirect werkende adiabatische koeling en recentlijk vooral de indirect werkende systemen zoals diabatische koeling (dauwpuntkoeling, al of niet uitgevoerd als statische koeling) vragen om kennis van het Mollierdiagram.

  11. Gold and palladium minerals (including empirical PdCuBiSe3) from the former Roter Bär mine, St. Andreasberg, Harz Mountains, Germany: a result of low-temperature, oxidising fluid overprint

    Science.gov (United States)

    Cabral, Alexandre Raphael; Ließmann, Wilfried; Lehmann, Bernd

    2015-10-01

    At Roter Bär, a former underground mine in the polymetallic deposits of St. Andreasberg in the middle-Harz vein district, Germany, native gold and palladium minerals occur very locally in clausthalite-hematite pockets of few millimetres across in carbonate veinlets. The native gold is a Au-Ag intermetallic compound and the palladium minerals are characterised as mertieite-II [Pd8(Sb,As)3] and empirical PdCuBiSe3 with some S. The latter coexists with bohdanowiczite (AgBiSe2), a mineral that is stable below 120 °C. The geological setting of Roter Bär, underneath a post-Variscan unconformity, and its hematite-selenide-gold association suggest that oxidising hydrothermal brines of low temperature were instrumental to the Au-Pd mineralisation. The Roter Bär Au-Pd mineralisation can be explained by Permo-Triassic, red-bed-derived brines in the context of post-Variscan, unconformity-related fluid overprint.

  12. New seismograph includes filters

    Energy Technology Data Exchange (ETDEWEB)

    1979-11-02

    The new Nimbus ES-1210 multichannel signal enhancement seismograph from EG and G geometrics has recently been redesigned to include multimode signal fillers on each amplifier. The ES-1210F is a shallow exploration seismograph for near subsurface exploration such as in depth-to-bedrock, geological hazard location, mineral exploration, and landslide investigations.

  13. Analytic device including nanostructures

    KAUST Repository

    Di Fabrizio, Enzo M.; Fratalocchi, Andrea; Totero Gongora, Juan Sebastian; Coluccio, Maria Laura; Candeloro, Patrizio; Cuda, Gianni

    2015-01-01

    A device for detecting an analyte in a sample comprising: an array including a plurality of pixels, each pixel including a nanochain comprising: a first nanostructure, a second nanostructure, and a third nanostructure, wherein size of the first nanostructure is larger than that of the second nanostructure, and size of the second nanostructure is larger than that of the third nanostructure, and wherein the first nanostructure, the second nanostructure, and the third nanostructure are positioned on a substrate such that when the nanochain is excited by an energy, an optical field between the second nanostructure and the third nanostructure is stronger than an optical field between the first nanostructure and the second nanostructure, wherein the array is configured to receive a sample; and a detector arranged to collect spectral data from a plurality of pixels of the array.

  14. Saskatchewan resources. [including uranium

    Energy Technology Data Exchange (ETDEWEB)

    1979-09-01

    The production of chemicals and minerals for the chemical industry in Saskatchewan are featured, with some discussion of resource taxation. The commodities mentioned include potash, fatty amines, uranium, heavy oil, sodium sulfate, chlorine, sodium hydroxide, sodium chlorate and bentonite. Following the successful outcome of the Cluff Lake inquiry, the uranium industry is booming. Some developments and production figures for Gulf Minerals, Amok, Cenex and Eldorado are mentioned.

  15. Being Included and Excluded

    DEFF Research Database (Denmark)

    Korzenevica, Marina

    2016-01-01

    Following the civil war of 1996–2006, there was a dramatic increase in the labor mobility of young men and the inclusion of young women in formal education, which led to the transformation of the political landscape of rural Nepal. Mobility and schooling represent a level of prestige that rural...... politics. It analyzes how formal education and mobility either challenge or reinforce traditional gendered norms which dictate a lowly position for young married women in the household and their absence from community politics. The article concludes that women are simultaneously excluded and included from...... community politics. On the one hand, their mobility and decision-making powers decrease with the increase in the labor mobility of men and their newly gained education is politically devalued when compared to the informal education that men gain through mobility, but on the other hand, schooling strengthens...

  16. Methods for the analysis of SO/sub 2/, SO/sub 3/ and H/sub 2/S in flue gas and the calculation of the acid dew point

    Energy Technology Data Exchange (ETDEWEB)

    Albertyn, C.H.

    1986-02-01

    Methods are given for the analysis of SO/sub 2/, SO/sub 3/, and H/sub 2/S in flue gas. Two methods are described for the determination of SO/sub 2/. The method to be used depends on whether or not H/sub 2/S is present in the gas stream. An equation for the calculation of acid dew point is given as well.

  17. Digital Earth Watch (DEW): How Mobile Apps Are Paving The Way Towards A Federated Web-Services Architecture For Citizen Science

    Science.gov (United States)

    Carrera, F.; Schloss, A. L.; Guerin, S.; Beaudry, J.; Pickle, J.

    2011-12-01

    Dozens of web-based initiatives allow citizens to provide information to programs that monitor the health of our environment. A concerned citizen can participate on-line as a weather "spotter", provide important phenological information to national databases, update bird counts in the area, or record the freezing of ponds, and much more. Many of these programs are developing mobile apps as companion tools to their web sites. Our group was involved in the development of one such companion app as an adjunct to the Picture Post project web site. Digital Earth Watch (DEW) and the Picture Post network support environmental monitoring through repeat digital photography and satellite imagery. A Picture Post is an eight-sided platform on a stand-alone post for taking a panoramic series of photographs. By taking pictures on a regular basis at Picture Post sites and by sharing these pictures on the program's web site (housed at the University of New Hampshire), citizen scientists are creating a photographic library of change-over-time in their local area and contributing to national monitoring programs. Our DEW Android application simplifies participation by allowing users to upload pictures instantly from their smart phone. The app also removes the constraint of the physical picture post, by allowing users to create a virtual post anywhere in the world. Posts have been set up to monitor trails, forests, water, wetlands, gardens and landscapes. The app uses the phone's GPS to position the virtual post in its geographic location and guides the user through the orientations thanks to the internal accelerometers and compass. To aid in the before-and-after comparison of images taken from the same orientation, the DEW app displays an "onionskin" of the prior image overlayed onto the camera viewfinder. With the transparent onionskin as a guide, the user can align the images more accurately, thus allowing differences between pictures to be detectable and measurable. The app

  18. Performance of operational radiosonde humidity sensors in direct comparison with a chilled mirror dew-point hygrometer and its climate implication

    Science.gov (United States)

    Wang, Junhong; Carlson, David J.; Parsons, David B.; Hock, Terrence F.; Lauritsen, Dean; Cole, Harold L.; Beierle, Kathryn; Chamberlain, Edward

    2003-08-01

    This study evaluates performance of humidity sensors in two widely used operational radiosondes, Vaisala and Sippican (formally VIZ), in comparison with a research quality, and potentially more accurate, chilled mirror dew-point hygrometer named ``Snow White''. A research radiosonde system carrying the Snow White (SW) hygrometer was deployed in the Oklahoma panhandle and at Dodge City, KS during the International H2O Project (IHOP_2002). A total of sixteen sondes were launched with either Vaisala RS80 or Sippican VIZ-B2 radiosondes on the same balloons. Comparisons of humidity data from the SW with Vaisala and Sippican data show that (a) Vaisala RS80-H agrees with the SW very well in the middle and lower troposphere, but has dry biases in the upper troposphere (UT), (b) Sippican carbon hygristor (CH) has time-lag errors throughout the troposphere and fails to respond to humidity changes in the UT, sometimes even in the middle troposphere, and (c) the SW can detect cirrus clouds near the tropopause and possibly estimate their ice water content (IWC). The failure of CH in the UT results in significant and artificial humidity shifts in radiosonde climate records at stations where a transition from VIZ to Vaisala radiosondes has occurred.

  19. Un versión española de la Escala de Estrategias de Afrontamiento de Maestros ante Estresores Laborales (Dewe, 1985

    Directory of Open Access Journals (Sweden)

    T. LOZANO-YAGÜE

    2003-01-01

    Full Text Available El objetivo propuesto fue adaptar la escala de Estrategias de Afrontamiento utilizadas por los Maestros ante Estresores Laborales (Dewe, 1985 a los docentes no universitarios españoles. Con tal propósito, la versión resultante del proceso de traducción-retrotraducción fue autocumplimentada, junto a otras escalas de referencia, por 172 docentes no universitarios dependientes del Ministerio de Educación y Cultura (M.E.C., analizándose posteriormente su fiabilidad (análisis factorial y análisis de la consistencia interna y validez (matriz de correlaciones. La versión obtenida resultó, a juicio de los participantes en la traducciónretrotraducción, equivalente conceptual, técnica y semánticamente con la versión original. A partir de dicha versión se consiguió una escala reducida compuesta de cinco factores y 27 variables, con unas adecuadas validez de contenido y de constructo (validez convergente y discriminante y fiabilidad (coeficiente alfa de Cronbach, ¿>0,7, para su aplicación en nuestro medio.

  20. Conversion of medium and low temperature heat to power

    Science.gov (United States)

    Fischer, Johann; Wendland, Martin; Lai, Ngoc Anh

    2013-04-01

    improvement. Presently, the best feasible systems seem to be ORC cycles using WF with a nearly vertical dew line in the T,s-diagram as HFO-1234yf, n-butane or cyclopentane and upper pressures close below or above (sORC) the critical pressure. Finally, we will consider the above cycles also with mixtures as WF including the Kalina cycle and coupled processes like cascade or multistage processes. [1] B Saleh, G Koglbauer, M Wendland, J Fischer, Working fluids for low temperature ORC-processes, Energy 32, 1210-21 (2007). [2] N A Lai, J Fischer, Efficiencies of Power Flash Cycles, Energy 44, 1017-27 (2012). [3] T Ho, S S Mao, R Greif, Comparison of the Organic Flash Cycle (OFC) to other advanced vapor cycles for intermediate and high temperature waste heat reclamation and solar thermal energy, Energy 42, 213-23 (2012).

  1. Prediction of water formation temperature in natural gas dehydrators using radial basis function (RBF neural networks

    Directory of Open Access Journals (Sweden)

    Tatar Afshin

    2016-03-01

    Full Text Available Raw natural gases usually contain water. It is very important to remove the water from these gases through dehydration processes due to economic reasons and safety considerations. One of the most important methods for water removal from these gases is using dehydration units which use Triethylene glycol (TEG. The TEG concentration at which all water is removed and dew point characteristics of mixture are two important parameters, which should be taken into account in TEG dehydration system. Hence, developing a reliable and accurate model to predict the performance of such a system seems to be very important in gas engineering operations. This study highlights the use of intelligent modeling techniques such as Multilayer perceptron (MLP and Radial Basis Function Neural Network (RBF-ANN to predict the equilibrium water dew point in a stream of natural gas based on the TEG concentration of stream and contractor temperature. Literature data set used in this study covers temperatures from 10 °C to 80 °C and TEG concentrations from 90.000% to 99.999%. Results showed that both models are accurate in prediction of experimental data and the MLP model gives more accurate predictions compared to RBF model.

  2. Evaluation of Dark Spots Formated on the High Temperature Metal Filter Elements

    International Nuclear Information System (INIS)

    Park, Seung Chul; Hwang, Tae Won; Moon, Chan Kook

    2008-01-01

    Metal filter elements were newly introduced to the high temperature filter (HTF) system in the low- and intermediate-level radioactive waste vitrification plant. In order to evaluate the performance of various metal materials as filter media, elements made of AISI 316L, AISI 904L, and Inconel 600 were included to the test set of filter elements. At the visual inspection to the elements performed after completion of each test, a few dark spots were observed on the surface of some elements. Especially they were found much more at the AISI 316L elements than others. To check the dark spots are the corrosion phenomena or not, two kinds of analyses were performed to the tested filter elements. Firstly, the surfaces or the cross sections of filter specimens cut out from both normal area and dark spot area of elements were analyzed by SEM/EDS. The results showed that the dark spots were not evidences of corrosion but the deposition of sodium, sulfur and silica compounds volatilized from waste or molten glass. Secondly, the ring tensile strength were analyzed for the ring-shape filter specimens cut out from each kind of element. The result obtained from the strength tested showed no evidence of corrosion as well. Conclusionally, depending on the two kinds of analysis, no evidences of corrosion were found at the tested metal filter elements. But the dark spots formed on the surface could reduce the effective filtering area and increase the overall pressure drop of HTF system. Thus, continuous heating inside filter housing up to dew point will be required normally. And a few long-period test should be followed for the exact evaluation of corrosion of the metal filter elements.

  3. The effects of sea surface temperature gradients on surface turbulent fluxes

    Science.gov (United States)

    Steffen, John

    A positive correlation between sea surface temperature (SST) and wind stress perturbation near strong SST gradients (DeltaSST) has been observed in different parts of the world ocean, such as the Gulf Stream in the North Atlantic and the Kuroshio Extension east of Japan. These changes in winds and SSTs can modify near-surface stability, surface stress, and latent and sensible heat fluxes. In general, these small scale processes are poorly modeled in Numerical Weather Prediction (NWP) and climate models. Failure to account for these air--sea interactions produces inaccurate values of turbulent fluxes, and therefore a misrepresentation of the energy, moisture, and momentum budgets. Our goal is to determine the change in these surface turbulent fluxes due to overlooking the correlated variability in winds, SSTs, and related variables. To model these air--sea interactions, a flux model was forced with and without SST--induced changes to the surface wind fields. The SST modification to the wind fields is based on a baroclinic argument as implemented by the University of Washington Planetary Boundary-Layer (UWPBL) model. Other input parameters include 2-m air temperature, 2-m dew point temperature, surface pressure (all from ERA--interim), and Reynolds Daily Optimum Interpolation Sea Surface Temperature (OISST). Flux model runs are performed every 6 hours starting in December 2002 and ending in November 2003. From these model outputs, seasonal, monthly, and daily means of the difference between DeltaSST and no DeltaSST effects on sensible heat flux (SHF), latent heat flux (LHF), and surface stress are calculated. Since the greatest impacts occur during the winter season, six additional December-January-February (DJF) seasons were analyzed for 1987--1990 and 1999--2002. The greatest differences in surface turbulent fluxes are concentrated near strong SST fronts associated with the Gulf Stream and Kuroshio Extension. On average, 2002---2003 DJF seasonal differences in SHF

  4. Estimativa da duração do período de molhamento por orvalho em um ecossistema cacau Estimate of the duration of the wetness period by dew in a cocoa ecosystem

    Directory of Open Access Journals (Sweden)

    Hermes A. de Almeida

    2009-12-01

    Full Text Available O objetivo deste trabalho foi estimar a duração do período de molhamento por orvalho (DPM, entre 18 e 06 h, utilizando-se dois modelos empíricos: a o do número de horas com umidade relativa > a 97% (NHUR > 97% e b o da depressão do ponto de orvalho The objective of this study was to estimate the duration of wetness by dew (DWW, from 18 to 06 h, using two empirical models: a number of hours with relative air humidity > 97% (NHUR > 97% and b depression of the dew point 61%, although the percentage for winter and summer months was 80.8 and 15.8% respectively. The high statistical indexes observed here show the viability of the models for estimating, with high precision, the DWW in a cocoa ecosystem. The models are of easy application and operation, dispensing the utilization of sensors and of more complex methods. Howerer, they still need some adjustments to be used for other crops and conditions.

  5. Warm Season Statistical Verification of the Pennsylvania State University Real Time Mesoscale Model Version 5

    National Research Council Canada - National Science Library

    Fitzgerald, Mark

    1998-01-01

    .... Variables that are verified include temperature, dew point, relative humidity, wind direction, wind speed, geopotential height, sea-level pressure, as well as the total totals severe weather index...

  6. A systematic approach to find the best road map for enhancement of a power plant with dew point inlet air pre-cooling of the air compressor

    International Nuclear Information System (INIS)

    Sohani, Ali; Farasati, Yashar; Sayyaadi, Hoseyn

    2017-01-01

    Highlights: • Dew-point cooler was proposed in order to enhance a power plant. • A systematic method to find the best road map was offered. • Investigation was done considering four optimization scenarios and different investment plans. • Payback period of the final plan was 2.67 years. • Annual net power and steam generation’s capability were improved 6.02% and 8.92%. - Abstract: Dimensional characteristics and operating parameters of the optimized Maisotsenko indirect evaporative cooler for pre-cooling of the compressor’s inlet air and consequently enhancement of the gas-turbine power generation system as well as the best investment strategy for it were found for an in-operation combined cycle power plant through a systematic approach. Four optimization scenarios were proposed considering different combinations of annual average of net power of the gas-turbine power generation system, payback period time and enthalpy difference of exhaust gases compared to the reference state of each gas-turbine power generation system as objective functions. In each scenario, optimization was conducted for different possible percentages of investment allocated to the research and development of the project. After that, analytical hierarchy process was used to find the best percentage of investment allocated to the research and development of the project of each scenario and the final selected one. Having introduced the approach, it was implemented for Montazer-Ghaem combined cycle power plant in Iran. The results showed for that case study, the analytical hierarchy process selected an optimization scenario in which the annual average of the net power and the enthalpy difference of the exhaust gases compared to the reference state were the objective functions and 15% of the total profit of the gas-turbine power generation system sold electricity was dedicated to the improvement project. This optimization had the payback period time of 2.67 years and it also improved

  7. Daily indoor-to-outdoor temperature and humidity relationships: a sample across seasons and diverse climatic regions.

    Science.gov (United States)

    Nguyen, Jennifer L; Dockery, Douglas W

    2016-02-01

    The health consequences of heat and cold are usually evaluated based on associations with outdoor measurements collected at a nearby weather reporting station. However, people in the developed world spend little time outdoors, especially during extreme temperature events. We examined the association between indoor and outdoor temperature and humidity in a range of climates. We measured indoor temperature, apparent temperature, relative humidity, dew point, and specific humidity (a measure of moisture content in air) for one calendar year (2012) in a convenience sample of eight diverse locations ranging from the equatorial region (10 °N) to the Arctic (64 °N). We then compared the indoor conditions to outdoor values recorded at the nearest airport weather station. We found that the shape of the indoor-to-outdoor temperature and humidity relationships varied across seasons and locations. Indoor temperatures showed little variation across season and location. There was large variation in indoor relative humidity between seasons and between locations which was independent of outdoor airport measurements. On the other hand, indoor specific humidity, and to a lesser extent dew point, tracked with outdoor, airport measurements both seasonally and between climates, across a wide range of outdoor temperatures. These results suggest that, in general, outdoor measures of actual moisture content in air better capture indoor conditions than outdoor temperature and relative humidity. Therefore, in studies where water vapor is among the parameters of interest for examining weather-related health effects, outdoor measurements of actual moisture content can be more reliably used as a proxy for indoor exposure than the more commonly examined variables of temperature and relative humidity.

  8. Statistical Correction of Air Temperature Forecasts for City and Road Weather Applications

    Science.gov (United States)

    Mahura, Alexander; Petersen, Claus; Sass, Bent; Gilet, Nicolas

    2014-05-01

    that the CPU time required for the operational procedure is relatively short (less than 15 minutes including a large time spent for interpolation). These also showed that in order to start correction of forecasts there is no need to have a long-term pre-historical data (containing forecasts and observations) and, at least, a couple of weeks will be sufficient when a new observational station is included and added to the forecast point. Note for the road weather application, the operationalization of the statistical correction of the road surface temperature forecasts (for the RWM system daily hourly runs covering forecast length up to 5 hours ahead) for the Danish road network (for about 400 road stations) was also implemented, and it is running in a test mode since Sep 2013. The method can also be applied for correction of the dew point temperature and wind speed (as a part of observations/ forecasts at synoptical stations), where these both meteorological parameters are parts of the proposed system of equations. The evaluation of the method performance for improvement of the wind speed forecasts is planned as well, with considering possibilities for the wind direction improvements (which is more complex due to multi-modal types of such data distribution). The method worked for the entire domain of mainland Denmark (tested for 60 synoptical and 395 road stations), and hence, it can be also applied for any geographical point within this domain, as through interpolation to about 100 cities' locations (for Danish national byvejr forecasts). Moreover, we can assume that the same method can be used in other geographical areas. The evaluation for other domains (with a focus on Greenland and Nordic countries) is planned. In addition, a similar approach might be also tested for statistical correction of concentrations of chemical species, but such approach will require additional elaboration and evaluation.

  9. Will the warmer temperature bring the more intensity precipitation?

    Science.gov (United States)

    Yutong, Z., II; Wang, T.

    2017-12-01

    Will the warmer temperature bring the more intensity precipitation?Over the past several decades, changes in climate are amplified over the Tibetan Plateau(TP), with warming trend almost being twice as large as the global average. In sharp contrast, there is a large spatial discrepancy of the variations in precipitation extremes, with increasing trends found in the southern and decreasing trends in central TP. These features motivate are urgent need for an observation-based understanding of how precipitation extremes respond to climate change. Here we examine the relation between precipitation intensity with atmospheric temperature, dew point temperature (Td) and convective available potential energy (CAPE) in Tibet Plateau. Owing to the influences of the westerlies and Indian monsoon on Tibetan climate, the stations can be divided into three sub-regions in TP: the westerlies region (north of 35°N, N = 28), the monsoon region (south of 30°N in TP, N = 31), and the transition region (located between 30°N and 35°N, N = 48). We found that the intensity precipitation does not follow the C-C relation and there is a mix of positive and negative slope. To better understand why different scaling occurs with temperature in district region, using the dew point temperature replace the temperature, although there is significant variability in relative humidity values, at most stations, there appears to be a general increase in relative humidity associated. It is likely that the observed rise in relative humidity can assist in explaining the negative scaling of extreme precipitation at westerlies domain and monsoon domain, with the primary reason why precipitation extremes expected to increase follows from the fact that a warmer atmosphere can "hold" more moisture. This suggests that not only on how much the moisture the atmosphere can hold, but on how much moisture exits in atmosphere. To understand the role of dynamic on extreme precipitation, we repeat the precipitation

  10. Projection of Korean Probable Maximum Precipitation under Future Climate Change Scenarios

    Directory of Open Access Journals (Sweden)

    Okjeong Lee

    2016-01-01

    Full Text Available According to the IPCC Fifth Assessment Report, air temperature and humidity of the future are expected to gradually increase over the current. In this study, future PMPs are estimated by using future dew point temperature projection data which are obtained from RCM data provided by the Korea Meteorological Administration. First, bias included in future dew point temperature projection data which is provided on a daily basis is corrected through a quantile-mapping method. Next, using a scale-invariance technique, 12-hour duration 100-year return period dew point temperatures which are essential input data for PMPs estimation are estimated from bias-corrected future dew point temperature data. After estimating future PMPs, it can be shown that PMPs in all future climate change scenarios (AR5 RCP2.6, RCP 4.5, RCP 6.0, and RCP 8.5 are very likely to increase.

  11. Effect of stress relief annealing temperature and atmosphere on the magnetic properties of silicon steel

    International Nuclear Information System (INIS)

    Paolinelli, Sebastiao C.; Cunha, Marco A. da

    2006-01-01

    Fully processed non-oriented silicon steel samples 0.50 mm thick were sheared and submitted to stress relief annealing under different conditions of temperature and atmosphere to investigate the effect of this treatment on the recovery of magnetic properties. Two different compositions were used, with different Si and Al contents. Temperature was varied in the range of 600-900 deg. C and four atmospheres were used: N 2 and N 2 +10%H 2 combined with dew points of -10 and 15 deg. C. The results showed that annealing atmosphere has very important effect on the magnetic properties and that the beneficial effect of stress relief annealing can be overcome by the detrimental effect of the atmosphere under certain conditions, due to oxidation and nitration

  12. Bonding evolution with sintering temperature in low alloyed steels with chromium

    Directory of Open Access Journals (Sweden)

    Fuentes-Pacheco L.

    2009-01-01

    Full Text Available At present, high performance PM steels for automotive applications follow a processing route that comprises die compaction of water-atomized powder, followed by sintering and secondary treatments, and finishing operations. This study examines Cr-alloyed sintered steels with two level of alloying. In chromium-alloyed steels, the surface oxide on the powder is of critical importance for developing the bonding between the particles during sintering. Reduction of this oxide depends mainly on three factors: temperature, dew point of the atmosphere, and carbothermic reduction provided by the added graphite. The transformation of the initial surface oxide evolves sequence as temperature increases during sintering, depending on the oxide composition. Carbothermic reduction is supposed to be the controlling mechanism, even when sintering in hydrogen-containing atmospheres. The effect of carbothermic reduction can be monitored by investigating the behavior of the specimens under tensile testing, and studying the resultant fracture surfaces.

  13. Dew Point Evaporative Comfort Cooling

    Science.gov (United States)

    2012-11-01

    Multiple DASs were installed at Fort Carson, and the data from all the sensors were stored and partially processed on Campbell Scientific Data Loggers. The...evaporative cooling technologies would be expected to easily overcome utility- scale water withdrawal rates. As an example, an evaluation of an...Ambient pressure Outdoor Setra 276 1% of full scale Pyranometer Horizontal Campbell Scientific CS300 5% of daily total The OAT measurement has an

  14. TFOS DEWS II Epidemiology Report.

    Science.gov (United States)

    Stapleton, Fiona; Alves, Monica; Bunya, Vatinee Y; Jalbert, Isabelle; Lekhanont, Kaevalin; Malet, Florence; Na, Kyung-Sun; Schaumberg, Debra; Uchino, Miki; Vehof, Jelle; Viso, Eloy; Vitale, Susan; Jones, Lyndon

    2017-07-01

    The subcommittee reviewed the prevalence, incidence, risk factors, natural history, morbidity and questionnaires reported in epidemiological studies of dry eye disease (DED). A meta-analysis of published prevalence data estimated the impact of age and sex. Global mapping of prevalence was undertaken. The prevalence of DED ranged from 5 to 50%. The prevalence of signs was higher and more variable than symptoms. There were limited prevalence studies in youth and in populations south of the equator. The meta-analysis confirmed that prevalence increases with age, however signs showed a greater increase per decade than symptoms. Women have a higher prevalence of DED than men, although differences become significant only with age. Risk factors were categorized as modifiable/non-modifiable, and as consistent, probable or inconclusive. Asian ethnicity was a mostly consistent risk factor. The economic burden and impact of DED on vision, quality of life, work productivity, psychological and physical impact of pain, are considerable, particularly costs due to reduced work productivity. Questionnaires used to evaluate DED vary in their utility. Future research should establish the prevalence of disease of varying severity, the incidence in different populations and potential risk factors such as youth and digital device usage. Geospatial mapping might elucidate the impact of climate, environment and socioeconomic factors. Given the limited study of the natural history of treated and untreated DED, this remains an important area for future research. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. TFOS DEWS II Epidemiology Report

    NARCIS (Netherlands)

    Stapleton, Fiona; Alves, Monica; Bunya, Vatinee Y.; Jalbert, Isabelle; Lekhanont, Kaevalin; Malet, Florence; Na, Kyung-Sun; Schaumberg, Debra; Uchino, Miki; Vehof, Jelle; Viso, Eloy; Vitale, Susan; Jones, Lyndon

    The subcommittee reviewed the prevalence, incidence, risk factors, natural history, morbidity and questionnaires reported in epidemiological studies of dry eye disease (DED). A meta-analysis of published prevalence data estimated the impact of age and sex. Global mapping of prevalence was

  16. (including travel dates) Proposed itinerary

    Indian Academy of Sciences (India)

    Ashok

    31 July to 22 August 2012 (including travel dates). Proposed itinerary: Arrival in Bangalore on 1 August. 1-5 August: Bangalore, Karnataka. Suggested institutions: Indian Institute of Science, Bangalore. St Johns Medical College & Hospital, Bangalore. Jawaharlal Nehru Centre, Bangalore. 6-8 August: Chennai, TN.

  17. Theory including future not excluded

    DEFF Research Database (Denmark)

    Nagao, K.; Nielsen, H.B.

    2013-01-01

    We study a complex action theory (CAT) whose path runs over not only past but also future. We show that, if we regard a matrix element defined in terms of the future state at time T and the past state at time TA as an expectation value in the CAT, then we are allowed to have the Heisenberg equation......, Ehrenfest's theorem, and the conserved probability current density. In addition,we showthat the expectation value at the present time t of a future-included theory for large T - t and large t - T corresponds to that of a future-not-included theory with a proper inner product for large t - T. Hence, the CAT...

  18. Composite material including nanocrystals and methods of making

    Science.gov (United States)

    Bawendi, Moungi G.; Sundar, Vikram C.

    2010-04-06

    Temperature-sensing compositions can include an inorganic material, such as a semiconductor nanocrystal. The nanocrystal can be a dependable and accurate indicator of temperature. The intensity of emission of the nanocrystal varies with temperature and can be highly sensitive to surface temperature. The nanocrystals can be processed with a binder to form a matrix, which can be varied by altering the chemical nature of the surface of the nanocrystal. A nanocrystal with a compatibilizing outer layer can be incorporated into a coating formulation and retain its temperature sensitive emissive properties.

  19. Device including a contact detector

    DEFF Research Database (Denmark)

    2011-01-01

    arms (12) may extend from the supporting body in co-planar relationship with the first surface. The plurality of cantilever arms (12) may extend substantially parallel to each other and each of the plurality of cantilever arms (12) may include an electrical conductive tip for contacting the area......The present invention relates to a probe for determining an electrical property of an area of a surface of a test sample, the probe is intended to be in a specific orientation relative to the test sample. The probe may comprise a supporting body defining a first surface. A plurality of cantilever...... of the test sample by movement of the probe relative to the surface of the test sample into the specific orientation.; The probe may further comprise a contact detector (14) extending from the supporting body arranged so as to contact the surface of the test sample prior to any one of the plurality...

  20. Neoclassical transport including collisional nonlinearity.

    Science.gov (United States)

    Candy, J; Belli, E A

    2011-06-10

    In the standard δf theory of neoclassical transport, the zeroth-order (Maxwellian) solution is obtained analytically via the solution of a nonlinear equation. The first-order correction δf is subsequently computed as the solution of a linear, inhomogeneous equation that includes the linearized Fokker-Planck collision operator. This equation admits analytic solutions only in extreme asymptotic limits (banana, plateau, Pfirsch-Schlüter), and so must be solved numerically for realistic plasma parameters. Recently, numerical codes have appeared which attempt to compute the total distribution f more accurately than in the standard ordering by retaining some nonlinear terms related to finite-orbit width, while simultaneously reusing some form of the linearized collision operator. In this work we show that higher-order corrections to the distribution function may be unphysical if collisional nonlinearities are ignored.

  1. Battery system with temperature sensors

    Science.gov (United States)

    Wood, Steven J.; Trester, Dale B.

    2012-11-13

    A battery system to monitor temperature includes at least one cell with a temperature sensing device proximate the at least one cell. The battery system also includes a flexible member that holds the temperature sensor proximate to the at least one cell.

  2. Temperature Pill

    Science.gov (United States)

    1988-01-01

    Ingestible Thermal Monitoring System was developed at Johns Hopkins University as means of getting internal temperature readings for treatments of such emergency conditions as dangerously low (hypothermia) and dangerously high (hyperthermia) body temperatures. ITMS's accuracy is off no more than one hundredth of a degree and provides the only means of obtaining deep body temperature. System has additional applicability in fertility monitoring and some aspects of surgery, critical care obstetrics, metabolic disease treatment, gerontology (aging) and food processing research. Three-quarter inch silicone capsule contains telemetry system, micro battery, and a quartz crystal temperature sensor inserted vaginally, rectally, or swallowed.

  3. Some problems on materials tests in high temperature hydrogen base gas mixture

    International Nuclear Information System (INIS)

    Shikama, Tatsuo; Tanabe, Tatsuhiko; Fujitsuka, Masakazu; Yoshida, Heitaro; Watanabe, Ryoji

    1980-01-01

    Some problems have been examined on materials tests (creep rupture tests and corrosion tests) in high temperature mixture gas of hydrogen (80%H 2 + 15%CO + 5%CO 2 ) simulating the reducing gas for direct steel making. H 2 , CO, CO 2 and CH 4 in the reducing gas interact with each other at elevated temperature and produce water vapor (H 2 O) and carbon (soot). Carbon deposited on the walls of retorts and the water condensed at pipings of the lower temperature gas outlet causes blocking of gas flow. The gas reactions have been found to be catalyzed by the retort walls, and appropriate selection of the materials for retorts has been found to mitigate the problems caused by water condensation and carbon deposition. Quartz has been recognized to be one of the most promising materials for minimizing the gas reactions. And ceramic coating, namely, BN (born nitride) on the heat resistant superalloy, MO-RE II, has reduced the amounts of water vapor and deposited carbon (sooting) produced by gas reactions and has kept dew points of outlet gas below room temperature. The well known emf (thermo-electromotive force) deterioration of Alumel-Chromel thermocouples in the reducing gases at elevated temperatures has been also found to be prevented by the ceramic (BN) coating. (author)

  4. Test plan for long-term, low-temperature oxidation of spent fuel, Series 1

    International Nuclear Information System (INIS)

    Einziger, R.E.

    1986-06-01

    Preliminary studies indicated the need for more spent fuel oxidation data in order to determine the probable behavior of spent fuel in a tuff repository. Long-term, low-temperature testing was recommended in a comprehensive technical approach to: (1) confirm the findings of the short-term thermogravimetric analyses scoping experiments; (2) evaluate the effects of variables such as burnup, atmospheric moisture and fuel type on the oxidation rate; and (3) extend the oxidation data base ot representative repository temperatures and better define the temperature dependence of the operative oxidation mechanisms. This document presents the Series 1 test plan to study, on a large number of samples, the effects of atmospheric moisture and temperature on oxidation rate and phase formation. Tests will run for up to two years, use characterized fragmented, and pulverized fuel samples, cover a temperature range of 110 0 C to 175 0 C and be conducted with an atmospheric moisture content rangeing from 0 C to approx. 80 0 C dew point. After testing, the samples will be examined and made available for leaching testing

  5. Developing HYDMN code to include the transient of MNSR

    International Nuclear Information System (INIS)

    Al-Barhoum, M.

    2000-11-01

    A description of the programs added to HYDMN code (a code for thermal-hydraulic steady state of MNSR) to include the transient of the same MNSR is presented. The code asks the initial conditions for the power (in k W) and the cold initial core inlet temperature (in degrees centigrade). A time-dependent study of the coolant inlet and outlet temperature, its speed, pool and tank temperatures is done for MNSR in general and for the Syrian MNSR in particular. The study solves the differential equations taken from reference (1) by using some numerical methods found in reference (3). The code becomes this way independent of any external information source. (Author)

  6. An overview of possible High Temperature Gas-cooled Reactors - Gas Turbine (HTGR-GT) systems for the production of electricity and heat. Includes a technical assessment of the suitability for a small Dutch cogeneration plant; Een overzicht van mogelijke HTGR-GT systemen voor produktie van elektriciteit en warmte. Met technische beoordeling van geschiktheid voor een kleine Nederlandse W/K centrale

    Energy Technology Data Exchange (ETDEWEB)

    Kikstra, J.F

    1997-06-01

    There is a large number of different configurations for the combination of a closed cycle gas turbine (CCGT) system and a high-temperature gas-cooled reactor (HTGR). Based on the results of a literature survey an overview of such configurations is presented and a comparison is made for their appropriateness for a small cogeneration system (<60 MWt) to be used in the Netherlands. However, most cycles can only be applied for large-scale energy production or supply heat on a too low temperature level. The direct, recuperated cycle is the only suitable cycle, while that cycle is a simple system and shows an acceptable electric and total efficiency. Calculations were carried out for the co-production of hot water (75-125C and 40-70C) and for steam (10 bar, 220C). By means of a static model and an optimizer the feasible efficiencies for different heat demand are determined. The maximum electric efficiency is 42% for the co-production of hot water and 38% for the co-production of steam. 28 refs.

  7. High temperature materials and mechanisms

    CERN Document Server

    2014-01-01

    The use of high-temperature materials in current and future applications, including silicone materials for handling hot foods and metal alloys for developing high-speed aircraft and spacecraft systems, has generated a growing interest in high-temperature technologies. High Temperature Materials and Mechanisms explores a broad range of issues related to high-temperature materials and mechanisms that operate in harsh conditions. While some applications involve the use of materials at high temperatures, others require materials processed at high temperatures for use at room temperature. High-temperature materials must also be resistant to related causes of damage, such as oxidation and corrosion, which are accelerated with increased temperatures. This book examines high-temperature materials and mechanisms from many angles. It covers the topics of processes, materials characterization methods, and the nondestructive evaluation and health monitoring of high-temperature materials and structures. It describes the ...

  8. The Effect of Deposit Temperature on the Catalytic SO2-to-SO3 Conversion in a Copper Flash Smelting Heat Recovery Boiler

    Science.gov (United States)

    Lehmusto, Juho; Vainio, Emil; Laurén, Tor; Lindgren, Mari

    2018-02-01

    The aim of the work was to study the catalytic role of copper flash smelter deposit in the SO2-to-SO3 conversion. In addition, the effect of process gas temperature at 548 K to 1173 K (275 °C to 900 °C) on the amount of SO3 formed was addressed both in the absence and presence of genuine copper flash smelter deposit. The SO3 conversion rate changed as a function of process gas temperature, peaking at 1023 K (750 °C). A dramatic increase in the SO2-to-SO3 conversion was observed when process dust was present, clearly indicating that process dust catalyzes the SO2-to-SO3 conversion. Based on these results, the catalytic ability of the deposit may lead to sulfuric acid dew point corrosion.

  9. Study on the conversion of H2 and CO from the helium carrier gas of high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Liao Cuiping; Zheng Zhenhong; Shi Fuen

    1995-01-01

    The conversions of hydrogen and carbon monoxide into water vapor and carbon dioxide on CuO-ZnO-Al 2 O 3 catalyst are studied. The effects of different temperature, system atmospheric pressure, impurity gas concentration, flow and dew point on properties of cupric oxide bed are investigated. The conversion characteristics curves of H 2 and CO are given. Experimental data of conversion capacity, action period and conversion efficiency of CuO-ZnO-Al 2 O 3 are obtained and the optimal parameters are determined. The results show that the concentration of H 2 and CO of the effluent gas after purification can reach below 2 x 10 -6 , respectively. So it can meet the demands of high temperature gas-cooled reactor and also provide optimal design parameters and reliable data for conversion of H 2 and CO on CuO-ZnO-Al 2 O 3 catalyst

  10. Modeling temperature and moisture fields in conditioned spaces using zonal approach, including sorption phenomena in buildings materials; Modelisation thermo-hydro-aeraulique des locaux climatises selon l'approche zonale (prise en compte des phenomenes de sorption d'humidite)

    Energy Technology Data Exchange (ETDEWEB)

    Cordeiro Mendoca, K.

    2004-05-15

    Building simulation models represent in our days an important tool for building conception and performance analysis. Although moisture interacts in many ways with the whole building affecting therefore its behavior, frequently these models neglects the interactions between them. In addition, in most of them, indoor air conditions are considered uniform, which is a non-realistic assumption in conditioned spaces. In this work, a model to predict temperature and moisture fields in conditioned spaces, using zonal approach, is proposed. This method is based in dividing spatially a room in a relative small number of zones, typically on the order of tens to hundreds, where the state variables of air are considered uniform, with the exception of pressure that varies hydrostatically. While not as fine-grained as CFD simulation, zonal models do give useful information about temperature and moisture distributions that is important in comfort analysis. The proposed model was structured in three groups of sub-models representing the three building domains: indoor air, envelope and HVAC system. The indoor air sub-model is related to the indoor air space, where airflow speed can be considered weak. The envelope sub-model is related to the radiation exchanges between envelope and its neighborhood, and to the simultaneous heat and mass transfers across the envelope material. This latest can be represented by four sub-models of different complexity levels, with two of them taking into account moisture adsorption and desorption by building materials. Concerning to the HVAC system model, it refers to the whole system that means equipment, control and specific airflow from equipment. All sub-models were coupled into a modular simulation environment, SPARK, well-adapted to compare different models. The applicability of the proposed model is shown by two examples. The first one shows the importance of considering moisture sorption phenomena in the prediction of indoor air conditions

  11. How is the operation of a dew point cooler effected? Part 1; Waardoor wordt de werking van een daupuntkoeler beinvloed? Deel 1

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, M. [Re/genT, Helmond (Netherlands); Uges, P.G.H. [StatiqCooling, Rijssen (Netherlands)

    2010-11-15

    A dewpoint cooler is defined as an indirect evaporative cooler with a countercurrent heat exchanger that cools the primary air, humidifies the process air and exudes it to the environment. Because of the countercurrent heat exchanger, the air outlet temperature is not limited to the wet bulb temperature. The structure consists of polypropylene slabs in which the primary air flow is conducted through the channels. The plates are covered with a hygroscopic foil. The process air is forced to flow between the plates and thus comes into direct contact with the foil. Water is supplied to the foil by means of a distribution system. A number of such systems has been experimentally investigated by Re/genT by order of StatiqCooling. [Dutch] Een dauwpuntkoeler wordt gedefinieerd als een indirecte verdampingskoeler met een tegenstroom warmtewisselaar die de primaire lucht koelt en de proceslucht bevochtigt en afgeeft aan de omgeving. Door de tegenstroomwarmtewisselaar is de luchtuitblaastemperatuur niet beperkt tot de natteboltemperatuur. De constructie bestaat uit polipropyleen kanaalplaten waarbij de primaire luchtstroom door de kanalen geleid wordt. De platen zijn bedekt met een hygroscopische folie. De proceslucht wordt gedwongen tussen de platen door te stromen en komt daarmee in direct contact met de folie. Aan de folie wordt water toegevoerd door middel van een distributiesysteem. Een aantal van dergelijke installaties is in opdracht van StatiqCooling experimenteel onderzocht door Re/genT.

  12. Temperature metrology

    Science.gov (United States)

    Fischer, J.; Fellmuth, B.

    2005-05-01

    The majority of the processes used by the manufacturing industry depend upon the accurate measurement and control of temperature. Thermal metrology is also a key factor affecting the efficiency and environmental impact of many high-energy industrial processes, the development of innovative products and the health and safety of the general population. Applications range from the processing, storage and shipment of perishable foodstuffs and biological materials to the development of more efficient and less environmentally polluting combustion processes for steel-making. Accurate measurement and control of temperature is, for instance, also important in areas such as the characterization of new materials used in the automotive, aerospace and semiconductor industries. This paper reviews the current status of temperature metrology. It starts with the determination of thermodynamic temperatures required on principle because temperature is an intensive quantity. Methods to determine thermodynamic temperatures are reviewed in detail to introduce the underlying physical basis. As these methods cannot usually be applied for practical measurements the need for a practical temperature scale for day-to-day work is motivated. The International Temperature Scale of 1990 and the Provisional Low Temperature Scale PLTS-2000 are described as important parts of the International System of Units to support science and technology. Its main importance becomes obvious in connection with industrial development and international markets. Every country is strongly interested in unique measures, in order to guarantee quality, reproducibility and functionability of products. The eventual realization of an international system, however, is only possible within the well-functioning organization of metrological laboratories. In developed countries the government established scientific institutes have certain metrological duties, as, for instance, the maintenance and dissemination of national

  13. Temperature metrology

    International Nuclear Information System (INIS)

    Fischer, J; Fellmuth, B

    2005-01-01

    The majority of the processes used by the manufacturing industry depend upon the accurate measurement and control of temperature. Thermal metrology is also a key factor affecting the efficiency and environmental impact of many high-energy industrial processes, the development of innovative products and the health and safety of the general population. Applications range from the processing, storage and shipment of perishable foodstuffs and biological materials to the development of more efficient and less environmentally polluting combustion processes for steel-making. Accurate measurement and control of temperature is, for instance, also important in areas such as the characterization of new materials used in the automotive, aerospace and semiconductor industries. This paper reviews the current status of temperature metrology. It starts with the determination of thermodynamic temperatures required on principle because temperature is an intensive quantity. Methods to determine thermodynamic temperatures are reviewed in detail to introduce the underlying physical basis. As these methods cannot usually be applied for practical measurements the need for a practical temperature scale for day-to-day work is motivated. The International Temperature Scale of 1990 and the Provisional Low Temperature Scale PLTS-2000 are described as important parts of the International System of Units to support science and technology. Its main importance becomes obvious in connection with industrial development and international markets. Every country is strongly interested in unique measures, in order to guarantee quality, reproducibility and functionability of products. The eventual realization of an international system, however, is only possible within the well-functioning organization of metrological laboratories. In developed countries the government established scientific institutes have certain metrological duties, as, for instance, the maintenance and dissemination of national

  14. High temperature niobium alloys

    International Nuclear Information System (INIS)

    Wojcik, C.C.

    1991-01-01

    Niobium alloys are currently being used in various high temperature applications such as rocket propulsion, turbine engines and lighting systems. This paper presents an overview of the various commercial niobium alloys, including basic manufacturing processes, properties and applications. Current activities for new applications include powder metallurgy, coating development and fabrication of advanced porous structures for lithium cooled heat pipes

  15. High temperature structural silicides

    International Nuclear Information System (INIS)

    Petrovic, J.J.

    1997-01-01

    Structural silicides have important high temperature applications in oxidizing and aggressive environments. Most prominent are MoSi 2 -based materials, which are borderline ceramic-intermetallic compounds. MoSi 2 single crystals exhibit macroscopic compressive ductility at temperatures below room temperature in some orientations. Polycrystalline MoSi 2 possesses elevated temperature creep behavior which is highly sensitive to grain size. MoSi 2 -Si 3 N 4 composites show an important combination of oxidation resistance, creep resistance, and low temperature fracture toughness. Current potential applications of MoSi 2 -based materials include furnace heating elements, molten metal lances, industrial gas burners, aerospace turbine engine components, diesel engine glow plugs, and materials for glass processing

  16. Cooling by evaporation. Alternative for air cooling below the dew point; Koelen door verdampen. Alternatief bij koelen van lucht onder het dauwpunt

    Energy Technology Data Exchange (ETDEWEB)

    Goossens, L.N.F.M. [Koninklijke Verhulst Luchtbehandeling, Waalwijk (Netherlands)

    1997-12-01

    One of the last developments in the indoor climate technology is desiccative evaporative cooling (DEC or cooling by dehumidification and evaporation). DEC is a combination of proven concepts, as e.g. adsorption, adiabatic cooling and heat recovery. DEC shows a high thermal comfort, low costs for exploitation and environment friendly components. The energy for drying requires a low-temperature level and can be produced by waste heat, a heat distribution system, through a cogeneration installation or by means of solar collectors. At the Royal Verhulst Air Conditioning company (`Koninklijke Verhulst Luchtbehandeling`) in Waalwijk, Netherlands, a DEC system was built to validate the programme to calculate the savings. In this article the principles and operation of the system (Roto-Cool) are briefly described. 4 figs., 2 ills.

  17. A survey of temperature measurement

    International Nuclear Information System (INIS)

    Saltvold, J.R.

    1976-03-01

    Many different techniques for measuring temperature have been surveyed and are discussed. The concept of temperature and the physical phenomena used in temperature measurement are also discussed. Extensive tables are presented in which the range and accuracy of the various techniques and other related data are included. (author)

  18. Asymetric change of daily temperature range: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Kukla, G. [ed.] [Columbia Univ., Palisades, NY (United States). Lamont-Doherty Earth Observatory; Karl, T.R. [ed.] [National Climatic Data Center, Asheville, NC (United States); Riches, M.R. [ed.] [USDOE, Washington, DC (United States)

    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.

  19. 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

  20. Micrometeorological data for energy-budget studies near Rogers Spring, Ash Meadows National Wildlife Refuge, Nye County, Nevada, 1994

    International Nuclear Information System (INIS)

    Nichols, W.D.; Rapp, T.R.

    1996-01-01

    The data were collected at two sites near Rogers Spring for use in energy-budget studies beginning in 1994. The data collected at each site included net radiation, air temperature at two heights, dew- point temperature at two heights, windspeed at two heights, soil heat flux, and soil temperature in the interval between the land surface and the buried heat-flux plates

  1. Ambient temperature signalling in plants.

    Science.gov (United States)

    Wigge, Philip A

    2013-10-01

    Plants are exposed to daily and seasonal fluctuations in temperature. Within the 'ambient' temperature range (about 12-27°C for Arabidopsis) temperature differences have large effects on plant growth and development, disease resistance pathways and the circadian clock without activating temperature stress pathways. It is this developmental sensing and response to non-stressful temperatures that will be covered in this review. Recent advances have revealed key players in mediating temperature signals. The bHLH transcription factor PHYTOCHROME INTERACTING FACTOR4 (PIF4) has been shown to be a hub for multiple responses to warmer temperature in Arabidopsis, including flowering and hypocotyl elongation. Changes in chromatin state are involved in transmitting temperature signals to the transcriptome. Determining the precise mechanisms of temperature perception represents an exciting goal for the field. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. temperature overspecification

    Directory of Open Access Journals (Sweden)

    Mehdi Dehghan

    2001-01-01

    Full Text Available Two different finite difference schemes for solving the two-dimensional parabolic inverse problem with temperature overspecification are considered. These schemes are developed for indentifying the control parameter which produces, at any given time, a desired temperature distribution at a given point in the spatial domain. The numerical methods discussed, are based on the (3,3 alternating direction implicit (ADI finite difference scheme and the (3,9 alternating direction implicit formula. These schemes are unconditionally stable. The basis of analysis of the finite difference equation considered here is the modified equivalent partial differential equation approach, developed from the 1974 work of Warming and Hyett [17]. This allows direct and simple comparison of the errors associated with the equations as well as providing a means to develop more accurate finite difference schemes. These schemes use less central processor times than the fully implicit schemes for two-dimensional diffusion with temperature overspecification. The alternating direction implicit schemes developed in this report use more CPU times than the fully explicit finite difference schemes, but their unconditional stability is significant. The results of numerical experiments are presented, and accuracy and the Central Processor (CPU times needed for each of the methods are discussed. We also give error estimates in the maximum norm for each of these methods.

  3. 42 CFR 410.100 - Included services.

    Science.gov (United States)

    2010-10-01

    ... service; however, maintenance therapy itself is not covered as part of these services. (c) Occupational... increase respiratory function, such as graded activity services; these services include physiologic... rehabilitation plan of treatment, including physical therapy services, occupational therapy services, speech...

  4. Static, Lightweight Includes Resolution for PHP

    NARCIS (Netherlands)

    M.A. Hills (Mark); P. Klint (Paul); J.J. Vinju (Jurgen)

    2014-01-01

    htmlabstractDynamic languages include a number of features that are challenging to model properly in static analysis tools. In PHP, one of these features is the include expression, where an arbitrary expression provides the path of the file to include at runtime. In this paper we present two

  5. Article Including Environmental Barrier Coating System

    Science.gov (United States)

    Lee, Kang N. (Inventor)

    2015-01-01

    An enhanced environmental barrier coating for a silicon containing substrate. The enhanced barrier coating may include a bond coat doped with at least one of an alkali metal oxide and an alkali earth metal oxide. The enhanced barrier coating may include a composite mullite bond coat including BSAS and another distinct second phase oxide applied over said surface.

  6. Rare thoracic cancers, including peritoneum mesothelioma

    NARCIS (Netherlands)

    Siesling, Sabine; van der Zwan, Jan Maarten; Izarzugaza, Isabel; Jaal, Jana; Treasure, Tom; Foschi, Roberto; Ricardi, Umberto; Groen, Harry; Tavilla, Andrea; Ardanaz, Eva

    Rare thoracic cancers include those of the trachea, thymus and mesothelioma (including peritoneum mesothelioma). The aim of this study was to describe the incidence, prevalence and survival of rare thoracic tumours using a large database, which includes cancer patients diagnosed from 1978 to 2002,

  7. Rare thoracic cancers, including peritoneum mesothelioma

    NARCIS (Netherlands)

    Siesling, Sabine; Zwan, J.M.V.D.; Izarzugaza, I.; Jaal, J.; Treasure, T.; Foschi, R.; Ricardi, U.; Groen, H.; Tavilla, A.; Ardanaz, E.

    2012-01-01

    Rare thoracic cancers include those of the trachea, thymus and mesothelioma (including peritoneum mesothelioma). The aim of this study was to describe the incidence, prevalence and survival of rare thoracic tumours using a large database, which includes cancer patients diagnosed from 1978 to 2002,

  8. Improving the strength of amalgams by including steel fibers

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, Calvin T. [Hendrix College, Conway, AR 72032 (United States); Van Hoose, James R. [Siemens, Orlando, FL 32826 (United States); McGill, Preston B. [Marshall Space Flight Center, EM20, Huntsville, AL 35812 (United States); Grugel, Richard N., E-mail: richard.n.grugel@nasa.gov [Marshall Space Flight Center, EM30, Huntsville, AL 35812 (United States)

    2012-05-30

    Highlights: Black-Right-Pointing-Pointer A room temperature liquid Ga-In alloy was successfully substituted for mercury. Black-Right-Pointing-Pointer Physically sound amalgams with included steel fibers can be made. Black-Right-Pointing-Pointer A small volume fraction inclusion of fibers increased strength by {approx}20%. - Abstract: Mercury amalgams, due to their material properties, are widely and successfully used in dental practice. They are, however, also well recognized as having poor tensile strength. With the possibility of expanding amalgam applications it is demonstrated that tensile strength can be increased some 20% by including a small amount of steel fibers. Furthermore, it is shown that mercury can be replaced with a room temperature liquid gallium-indium alloy. Processing, microstructures, and mechanical test results of these novel amalgams are presented and discussed in view of means to further improve their properties.

  9. Temperature in the throat

    Directory of Open Access Journals (Sweden)

    Dariush Kaviani

    2016-09-01

    Full Text Available We study the temperature of extended objects in string theory. Rotating probe D-branes admit horizons and temperatures a la Unruh effect. We find that the induced metrics on slow rotating probe D1-branes in holographic string solutions including warped Calabi–Yau throats have distinct thermal horizons with characteristic Hawking temperatures even if there is no black hole in the bulk Calabi–Yau. Taking the UV/IR limits of the solution, we show that the world volume black hole nucleation depends on the deformation and the warping of the throat. We find that world volume horizons and temperatures of expected features form not in the regular confining IR region but in the singular nonconfining UV solution. In the conformal limit of the UV, we find horizons and temperatures similar to those on rotating probes in the AdS throat found in the literature. In this case, we also find that activating a background gauge field form the U(1 R-symmetry modifies the induced metric with its temperature describing two different classes of black hole solutions.

  10. Thermodynamics of strong coupling superconductors including the effect of anisotropy

    Science.gov (United States)

    Daams, J. M.; Carbotte, J. P.

    1981-05-01

    The thermodynamics of several elemental superconductors is computed from isotropic Eliashberg theory formulated on the imaginary frequency axis. A symmary of the available experimental literature is presented and a comparison with theory is given. The small disagreements that are found are all in the direction expected from anisotropy effects. We calculate the effect of a small amount of model anisotropy on the critical temperature, critical field, and high-temperature specific heat from an exact solution of the anisotropic Eliashberg equations. These are the first such results below the critical temperature; unlike previous analytical work, we include retardation, anisotropy in the mass enhancement, and the effect of the Coulomb repulsion in enhancing anisotropy, all of which are significant. We derive a new formula independent of any model anisotropy for the rate of decrease with impurity lifetime of the critical temperature. Finally we demonstrate how the commonly used formulas of Markowitz and Kadanoff and of Clem may give entirely misleading estimates of the gap anisotropy when used to interpret certain experiments.

  11. Births and deaths including fetal deaths

    Data.gov (United States)

    U.S. Department of Health & Human Services — Access to a variety of United States birth and death files including fetal deaths: Birth Files, 1968-2009; 1995-2005; Fetal death file, 1982-2005; Mortality files,...

  12. High-Temperature Piezoelectric Sensing

    Directory of Open Access Journals (Sweden)

    Xiaoning Jiang

    2013-12-01

    Full Text Available Piezoelectric sensing is of increasing interest for high-temperature applications in aerospace, automotive, power plants and material processing due to its low cost, compact sensor size and simple signal conditioning, in comparison with other high-temperature sensing techniques. This paper presented an overview of high-temperature piezoelectric sensing techniques. Firstly, different types of high-temperature piezoelectric single crystals, electrode materials, and their pros and cons are discussed. Secondly, recent work on high-temperature piezoelectric sensors including accelerometer, surface acoustic wave sensor, ultrasound transducer, acoustic emission sensor, gas sensor, and pressure sensor for temperatures up to 1,250 °C were reviewed. Finally, discussions of existing challenges and future work for high-temperature piezoelectric sensing are presented.

  13. Including Indigenous Minorities in Decision-Making

    DEFF Research Database (Denmark)

    Pristed Nielsen, Helene

    Based on theories of public sphere participation and deliberative democracy, this book presents empirical results from a study of experiences with including Aboriginal and Maori groups in political decision-making in respectively Western Australia and New Zealand......Based on theories of public sphere participation and deliberative democracy, this book presents empirical results from a study of experiences with including Aboriginal and Maori groups in political decision-making in respectively Western Australia and New Zealand...

  14. Gas storage materials, including hydrogen storage materials

    Science.gov (United States)

    Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

    2013-02-19

    A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

  15. Estimating plasma temperatures

    International Nuclear Information System (INIS)

    Nash, J.K.; Iglesias, C.A.; Chen, M.H.; Rogers, F.J.

    1992-04-01

    Recent laser-produced plasma experiments have relied on spectroscopic comparisons with models to infer plasma temperatures. The models use an experimentally determined value for the matter density as input and treat the temperature as a free parameter to obtain a best fit to the experimental absorption spectrum. However, uncertainties in the ionization balance theories lead to inferred temperatures that are model dependent. We report results of a new approach which combines high=quality atomic data with an ionization balance obtained from systematic expansions of the grand canonical ensemble. The latter avoids the ad hoc cutoffs required in free energy minimization schemes and includes Coulomb corrections usually neglected in other models. Comparisons to experimental spectra show excellent agreement

  16. Comparing daily temperature averaging methods: the role of surface and atmosphere variables in determining spatial and seasonal variability

    Science.gov (United States)

    Bernhardt, Jase; Carleton, Andrew M.

    2018-05-01

    The two main methods for determining the average daily near-surface air temperature, twice-daily averaging (i.e., [Tmax+Tmin]/2) and hourly averaging (i.e., the average of 24 hourly temperature measurements), typically show differences associated with the asymmetry of the daily temperature curve. To quantify the relative influence of several land surface and atmosphere variables on the two temperature averaging methods, we correlate data for 215 weather stations across the Contiguous United States (CONUS) for the period 1981-2010 with the differences between the two temperature-averaging methods. The variables are land use-land cover (LULC) type, soil moisture, snow cover, cloud cover, atmospheric moisture (i.e., specific humidity, dew point temperature), and precipitation. Multiple linear regression models explain the spatial and monthly variations in the difference between the two temperature-averaging methods. We find statistically significant correlations between both the land surface and atmosphere variables studied with the difference between temperature-averaging methods, especially for the extreme (i.e., summer, winter) seasons (adjusted R2 > 0.50). Models considering stations with certain LULC types, particularly forest and developed land, have adjusted R2 values > 0.70, indicating that both surface and atmosphere variables control the daily temperature curve and its asymmetry. This study improves our understanding of the role of surface and near-surface conditions in modifying thermal climates of the CONUS for a wide range of environments, and their likely importance as anthropogenic forcings—notably LULC changes and greenhouse gas emissions—continues.

  17. Fog, cloud, and dew chemistry. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, M.R.

    1989-02-28

    The spatial and temporal variations of fog/cloud chemistry were determined in the San Joaquin Valley, in the Los Angeles Basin, and in the Santa Barbara Channel area using automated fog- and cloudwater collectors that were designed and constructed for the project. A significant correlation was observed between the average nighttime cloud- and fogwater loadings of H/sup +/ and NO/sub 3//sup /minus// and the maximum levels of O/sub 3//sup /minus//. Higher aldehydes, a series of dicarbonyls, and a variety of sulfonic acid salts formed by reaction of S(IV) and aldehydes were quantitatively determined in the droplet phase.

  18. High temperature materials; Materiaux a hautes temperatures

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    The aim of this workshop is to share the needs of high temperature and nuclear fuel materials for future nuclear systems, to take stock of the status of researches in this domain and to propose some cooperation works between the different research organisations. The future nuclear systems are the very high temperature (850 to 1200 deg. C) gas cooled reactors (GCR) and the molten salt reactors (MSR). These systems include not only the reactor but also the fabrication and reprocessing of the spent fuel. This document brings together the transparencies of 13 communications among the 25 given at the workshop: 1) characteristics and needs of future systems: specifications, materials and fuel needs for fast spectrum GCR and very high temperature GCR; 2) high temperature materials out of neutron flux: thermal barriers: materials, resistance, lifetimes; nickel-base metal alloys: status of knowledge, mechanical behaviour, possible applications; corrosion linked with the gas coolant: knowledge and problems to be solved; super-alloys for turbines: alloys for blades and discs; corrosion linked with MSR: knowledge and problems to be solved; 3) materials for reactor core structure: nuclear graphite and carbon; fuel assembly structure materials of the GCR with fast neutron spectrum: status of knowledge and ceramics and cermets needs; silicon carbide as fuel confinement material, study of irradiation induced defects; migration of fission products, I and Cs in SiC; 4) materials for hydrogen production: status of the knowledge and needs for the thermochemical cycle; 5) technologies: GCR components and the associated material needs: compact exchangers, pumps, turbines; MSR components: valves, exchangers, pumps. (J.S.)

  19. Electric Power Monthly, August 1990. [Glossary included

    Energy Technology Data Exchange (ETDEWEB)

    1990-11-29

    The Electric Power Monthly (EPM) presents monthly summaries of electric utility statistics at the national, Census division, and State level. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data includes generation by energy source (coal, oil, gas, hydroelectric, and nuclear); generation by region; consumption of fossil fuels for power generation; sales of electric power, cost data; and unusual occurrences. A glossary is included.

  20. Electrochemical cell structure including an ionomeric barrier

    Science.gov (United States)

    Lambert, Timothy N.; Hibbs, Michael

    2017-06-20

    An apparatus includes an electrochemical half-cell comprising: an electrolyte, an anode; and an ionomeric barrier positioned between the electrolyte and the anode. The anode may comprise a multi-electron vanadium phosphorous alloy, such as VP.sub.x, wherein x is 1-5. The electrochemical half-cell is configured to oxidize the vanadium and phosphorous alloy to release electrons. A method of mitigating corrosion in an electrochemical cell includes disposing an ionomeric barrier in a path of electrolyte or ion flow to an anode and mitigating anion accumulation on the surface of the anode.

  1. Isolators Including Main Spring Linear Guide Systems

    Science.gov (United States)

    Goold, Ryan (Inventor); Buchele, Paul (Inventor); Hindle, Timothy (Inventor); Ruebsamen, Dale Thomas (Inventor)

    2017-01-01

    Embodiments of isolators, such as three parameter isolators, including a main spring linear guide system are provided. In one embodiment, the isolator includes first and second opposing end portions, a main spring mechanically coupled between the first and second end portions, and a linear guide system extending from the first end portion, across the main spring, and toward the second end portion. The linear guide system expands and contracts in conjunction with deflection of the main spring along the working axis, while restricting displacement and rotation of the main spring along first and second axes orthogonal to the working axis.

  2. High temperature storage loop :

    Energy Technology Data Exchange (ETDEWEB)

    Gill, David Dennis; Kolb, William J.

    2013-07-01

    A three year plan for thermal energy storage (TES) research was created at Sandia National Laboratories in the spring of 2012. This plan included a strategic goal of providing test capability for Sandia and for the nation in which to evaluate high temperature storage (>650ÀC) technology. The plan was to scope, design, and build a flow loop that would be compatible with a multitude of high temperature heat transfer/storage fluids. The High Temperature Storage Loop (HTSL) would be reconfigurable so that it was useful for not only storage testing, but also for high temperature receiver testing and high efficiency power cycle testing as well. In that way, HTSL was part of a much larger strategy for Sandia to provide a research and testing platform that would be integral for the evaluation of individual technologies funded under the SunShot program. DOEs SunShot program seeks to reduce the price of solar technologies to 6/kWhr to be cost competitive with carbon-based fuels. The HTSL project sought to provide evaluation capability for these SunShot supported technologies. This report includes the scoping, design, and budgetary costing aspects of this effort

  3. 28 CFR 20.32 - Includable offenses.

    Science.gov (United States)

    2010-07-01

    ... Exchange of Criminal History Record Information § 20.32 Includable offenses. (a) Criminal history record... vehicular manslaughter, driving under the influence of drugs or liquor, and hit and run), when unaccompanied by a § 20.32(a) offense. These exclusions may not be applicable to criminal history records...

  4. Including Students with Visual Impairments: Softball

    Science.gov (United States)

    Brian, Ali; Haegele, Justin A.

    2014-01-01

    Research has shown that while students with visual impairments are likely to be included in general physical education programs, they may not be as active as their typically developing peers. This article provides ideas for equipment modifications and game-like progressions for one popular physical education unit, softball. The purpose of these…

  5. Extending flood damage assessment methodology to include ...

    African Journals Online (AJOL)

    Optimal and sustainable flood plain management, including flood control, can only be achieved when the impacts of flood control measures are considered for both the man-made and natural environments, and the sociological aspects are fully considered. Until now, methods/models developed to determine the influences ...

  6. BIOLOGIC AND ECONOMIC EFFECTS OF INCLUDING DIFFERENT ...

    African Journals Online (AJOL)

    The biologic and economic effects of including three agro-industrial by-products as ingredients in turkey poult diets were investigated using 48 turkey poults in a completely randomised design experiment. Diets were formulated to contain the three by-products – wheat offal, rice husk and palm kernel meal, each at 20% level ...

  7. Including Children Dependent on Ventilators in School.

    Science.gov (United States)

    Levine, Jack M.

    1996-01-01

    Guidelines for including ventilator-dependent children in school are offered, based on experience with six such students at a New York State school. Guidelines stress adherence to the medical management plan, the school-family partnership, roles of the social worker and psychologist, orientation, transportation, classroom issues, and steps toward…

  8. Photoactive devices including porphyrinoids with coordinating additives

    Science.gov (United States)

    Forrest, Stephen R; Zimmerman, Jeramy; Yu, Eric K; Thompson, Mark E; Trinh, Cong; Whited, Matthew; Diev, Vlacheslav

    2015-05-12

    Coordinating additives are included in porphyrinoid-based materials to promote intermolecular organization and improve one or more photoelectric characteristics of the materials. The coordinating additives are selected from fullerene compounds and organic compounds having free electron pairs. Combinations of different coordinating additives can be used to tailor the characteristic properties of such porphyrinoid-based materials, including porphyrin oligomers. Bidentate ligands are one type of coordinating additive that can form coordination bonds with a central metal ion of two different porphyrinoid compounds to promote porphyrinoid alignment and/or pi-stacking. The coordinating additives can shift the absorption spectrum of a photoactive material toward higher wavelengths, increase the external quantum efficiency of the material, or both.

  9. Electric power monthly, September 1990. [Glossary included

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-17

    The purpose of this report is to provide energy decision makers with accurate and timely information that may be used in forming various perspectives on electric issues. The power plants considered include coal, petroleum, natural gas, hydroelectric, and nuclear power plants. Data are presented for power generation, fuel consumption, fuel receipts and cost, sales of electricity, and unusual occurrences at power plants. Data are compared at the national, Census division, and state levels. 4 figs., 52 tabs. (CK)

  10. Nuclear reactor shield including magnesium oxide

    International Nuclear Information System (INIS)

    Rouse, C.A.; Simnad, M.T.

    1981-01-01

    An improvement is described for nuclear reactor shielding of a type used in reactor applications involving significant amounts of fast neutron flux. The reactor shielding includes means providing structural support, neutron moderator material, neutron absorber material and other components, wherein at least a portion of the neutron moderator material is magnesium in the form of magnesium oxide either alone or in combination with other moderator materials such as graphite and iron

  11. Model for safety reports including descriptive examples

    International Nuclear Information System (INIS)

    1995-12-01

    Several safety reports will be produced in the process of planning and constructing the system for disposal of high-level radioactive waste in Sweden. The present report gives a model, with detailed examples, of how these reports should be organized and what steps they should include. In the near future safety reports will deal with the encapsulation plant and the repository. Later reports will treat operation of the handling systems and the repository

  12. Jet-calculus approach including coherence effects

    International Nuclear Information System (INIS)

    Jones, L.M.; Migneron, R.; Narayanan, K.S.S.

    1987-01-01

    We show how integrodifferential equations typical of jet calculus can be combined with an averaging procedure to obtain jet-calculus-based results including the Mueller interference graphs. Results in longitudinal-momentum fraction x for physical quantities are higher at intermediate x and lower at large x than with the conventional ''incoherent'' jet calculus. These results resemble those of Marchesini and Webber, who used a Monte Carlo approach based on the same dynamics

  13. [Renal patient's diet: Can fish be included?].

    Science.gov (United States)

    Castro González, M I; Maafs Rodríguez, A G; Galindo Gómez, C

    2012-01-01

    Medical and nutritional treatment for renal disease, now a major public health issue, is highly complicated. Nutritional therapy must seek to retard renal dysfunction, maintain an optimal nutritional status and prevent the development of underlying pathologies. To analyze ten fish species to identify those that, because of their low phosphorus content, high biological value protein and elevated n-3 fatty acids EPA and DHA, could be included in renal patient's diet. The following fish species (Litte tunny, Red drum, Spotted eagleray, Escolar, Swordfish, Big-scale pomfret, Cortez flounder, Largemouth blackbass, Periche mojarra, Florida Pompano) were analyzed according to the AOAC and Keller techniques to determine their protein, phosphorus, sodium, potassium, cholesterol, vitamins D(3) and E, and n-3 EPA+DHA content. These results were used to calculate relations between nutrients. The protein in the analyzed species ranged from 16.5 g/100 g of fillet (Largemouth black bass) to 27.2 g/100 g (Red drum); the lowest phosphorus value was 28.6 mg/100 g (Periche mojarra) and the highest 216.3 mg/100 g (Spotted eagle ray). 80% of the fish presented > 100 mg EPA + DHA in 100 g of fillet. By its Phosphorus/gProtein ratio, Escolar and Swordfish could not be included in the renal diet; Little tunny, Escolar, Big-scale pomfret, Largemouth black-bass, Periche mojarra and Florida Pompano presented a lower Phosphorus/EPA + DHA ratio. Florida pompano is the most recommended specie for renal patients, due to its optimal nutrient relations. However, all analyzed species, except Escolar and Swordfish, could be included in renal diets.

  14. MOS modeling hierarchy including radiation effects

    International Nuclear Information System (INIS)

    Alexander, D.R.; Turfler, R.M.

    1975-01-01

    A hierarchy of modeling procedures has been developed for MOS transistors, circuit blocks, and integrated circuits which include the effects of total dose radiation and photocurrent response. The models were developed for use with the SCEPTRE circuit analysis program, but the techniques are suitable for other modern computer aided analysis programs. The modeling hierarchy permits the designer or analyst to select the level of modeling complexity consistent with circuit size, parametric information, and accuracy requirements. Improvements have been made in the implementation of important second order effects in the transistor MOS model, in the definition of MOS building block models, and in the development of composite terminal models for MOS integrated circuits

  15. Drug delivery device including electrolytic pump

    KAUST Repository

    Foulds, Ian G.; Buttner, Ulrich; Yi, Ying

    2016-01-01

    Systems and methods are provided for a drug delivery device and use of the device for drug delivery. In various aspects, the drug delivery device combines a “solid drug in reservoir” (SDR) system with an electrolytic pump. In various aspects an improved electrolytic pump is provided including, in particular, an improved electrolytic pump for use with a drug delivery device, for example an implantable drug delivery device. A catalytic reformer can be incorporated in a periodically pulsed electrolytic pump to provide stable pumping performance and reduced actuation cycle.

  16. Drug delivery device including electrolytic pump

    KAUST Repository

    Foulds, Ian G.

    2016-03-31

    Systems and methods are provided for a drug delivery device and use of the device for drug delivery. In various aspects, the drug delivery device combines a “solid drug in reservoir” (SDR) system with an electrolytic pump. In various aspects an improved electrolytic pump is provided including, in particular, an improved electrolytic pump for use with a drug delivery device, for example an implantable drug delivery device. A catalytic reformer can be incorporated in a periodically pulsed electrolytic pump to provide stable pumping performance and reduced actuation cycle.

  17. Energy principle with included boundary conditions

    International Nuclear Information System (INIS)

    Lehnert, B.

    1994-01-01

    Earlier comments by the author on the limitations of the classical form of the extended energy principle are supported by a complementary analysis on the potential energy change arising from free-boundary displacements of a magnetically confined plasma. In the final formulation of the extended principle, restricted displacements, satisfying pressure continuity by means of plasma volume currents in a thin boundary layer, are replaced by unrestricted (arbitrary) displacements which can give rise to induced surface currents. It is found that these currents contribute to the change in potential energy, and that their contribution is not taken into account by such a formulation. A general expression is further given for surface currents induced by arbitrary displacements. The expression is used to reformulate the energy principle for the class of displacements which satisfy all necessary boundary conditions, including that of the pressure balance. This makes a minimization procedure of the potential energy possible, for the class of all physically relevant test functions which include the constraints imposed by the boundary conditions. Such a procedure is also consistent with a corresponding variational calculus. (Author)

  18. Aerosol simulation including chemical and nuclear reactions

    International Nuclear Information System (INIS)

    Marwil, E.S.; Lemmon, E.C.

    1985-01-01

    The numerical simulation of aerosol transport, including the effects of chemical and nuclear reactions presents a challenging dynamic accounting problem. Particles of different sizes agglomerate and settle out due to various mechanisms, such as diffusion, diffusiophoresis, thermophoresis, gravitational settling, turbulent acceleration, and centrifugal acceleration. Particles also change size, due to the condensation and evaporation of materials on the particle. Heterogeneous chemical reactions occur at the interface between a particle and the suspending medium, or a surface and the gas in the aerosol. Homogeneous chemical reactions occur within the aersol suspending medium, within a particle, and on a surface. These reactions may include a phase change. Nuclear reactions occur in all locations. These spontaneous transmutations from one element form to another occur at greatly varying rates and may result in phase or chemical changes which complicate the accounting process. This paper presents an approach for inclusion of these effects on the transport of aerosols. The accounting system is very complex and results in a large set of stiff ordinary differential equations (ODEs). The techniques for numerical solution of these ODEs require special attention to achieve their solution in an efficient and affordable manner. 4 refs

  19. Addressing Stillbirth in India Must Include Men.

    Science.gov (United States)

    Roberts, Lisa; Montgomery, Susanne; Ganesh, Gayatri; Kaur, Harinder Pal; Singh, Ratan

    2017-07-01

    Millennium Development Goal 4, to reduce child mortality, can only be achieved by reducing stillbirths globally. A confluence of medical and sociocultural factors contribute to the high stillbirth rates in India. The psychosocial aftermath of stillbirth is a well-documented public health problem, though less is known of the experience for men, particularly outside of the Western context. Therefore, men's perceptions and knowledge regarding reproductive health, as well as maternal-child health are important. Key informant interviews (n = 5) were analyzed and 28 structured interviews were conducted using a survey based on qualitative themes. Qualitative themes included men's dual burden and right to medical and reproductive decision making power. Wives were discouraged from expressing grief and pushed to conceive again. If not successful, particularly if a son was not conceived, a second wife was considered a solution. Quantitative data revealed that men with a history of stillbirths had greater anxiety and depression, perceived less social support, but had more egalitarian views towards women than men without stillbirth experience. At the same time fathers of stillbirths were more likely to be emotionally or physically abusive. Predictors of mental health, attitudes towards women, and perceived support are discussed. Patriarchal societal values, son preference, deficient women's autonomy, and sex-selective abortion perpetuate the risk for future poor infant outcomes, including stillbirth, and compounds the already higher risk of stillbirth for males. Grief interventions should explore and take into account men's perceptions, attitudes, and behaviors towards reproductive decision making.

  20. Modelling global fresh surface water temperature

    NARCIS (Netherlands)

    Beek, L.P.H. van; Eikelboom, T.; Vliet, M.T.H. van; Bierkens, M.F.P.

    2011-01-01

    Temperature directly determines a range of water physical properties including vapour pressure, surface tension, density and viscosity, and the solubility of oxygen and other gases. Indirectly water temperature acts as a strong control on fresh water biogeochemistry, influencing sediment

  1. Apparatus Would Measure Temperatures Of Ball Bearings

    Science.gov (United States)

    Gibson, John C.; Fredricks, Thomas H.

    1995-01-01

    Rig for testing ball bearings under radial and axial loads and measuring surface temperatures undergoing development. Includes extensible thermocouples: by means of bellows as longitudinal positioners, thermocouples driven into contact with bearing balls to sense temperatures immediately after test run. Not necessary to disassemble rig or to section balls to obtain indirect indications of maximum temperatures reached. Thermocouple measurements indicate temperatures better than temperature-sensitive paints.

  2. Including gauge corrections to thermal leptogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Huetig, Janine

    2013-05-17

    This thesis provides the first approach of a systematic inclusion of gauge corrections to leading order to the ansatz of thermal leptogenesis. We have derived a complete expression for the integrated lepton number matrix including all resummations needed. For this purpose, a new class of diagram has been invented, namely the cylindrical diagram, which allows diverse investigations into the topic of leptogenesis such as the case of resonant leptogenesis. After a brief introduction of the topic of the baryon asymmetry in the universe and a discussion of its most promising solutions as well as their advantages and disadvantages, we have presented our framework of thermal leptogenesis. An effective model was described as well as the associated Feynman rules. The basis for using nonequilibrium quantum field theory has been built in chapter 3. At first, the main definitions have been presented for equilibrium thermal field theory, afterwards we have discussed the Kadanoff-Baym equations for systems out of equilibrium using the example of the Majorana neutrino. The equations have also been solved in the context of leptogenesis in chapter 4. Since gauge corrections play a crucial role throughout this thesis, we have also repeated the naive ansatz by replacing the free equilibrium propagator by propagators including thermal damping rates due to the Standard Model damping widths for lepton and Higgs fields. It is shown that this leads to a comparable result to the solutions of the Boltzmann equations for thermal leptogenesis. Thus it becomes obvious that Standard Model corrections are not negligible for thermal leptogenesis and therefore need to be included systematically from first principles. In order to achieve this we have started discussing the calculation of ladder rung diagrams for Majorana neutrinos using the HTL and the CTL approach in chapter 5. All gauge corrections are included in this framework and thus it has become the basis for the following considerations

  3. Including gauge corrections to thermal leptogenesis

    International Nuclear Information System (INIS)

    Huetig, Janine

    2013-01-01

    This thesis provides the first approach of a systematic inclusion of gauge corrections to leading order to the ansatz of thermal leptogenesis. We have derived a complete expression for the integrated lepton number matrix including all resummations needed. For this purpose, a new class of diagram has been invented, namely the cylindrical diagram, which allows diverse investigations into the topic of leptogenesis such as the case of resonant leptogenesis. After a brief introduction of the topic of the baryon asymmetry in the universe and a discussion of its most promising solutions as well as their advantages and disadvantages, we have presented our framework of thermal leptogenesis. An effective model was described as well as the associated Feynman rules. The basis for using nonequilibrium quantum field theory has been built in chapter 3. At first, the main definitions have been presented for equilibrium thermal field theory, afterwards we have discussed the Kadanoff-Baym equations for systems out of equilibrium using the example of the Majorana neutrino. The equations have also been solved in the context of leptogenesis in chapter 4. Since gauge corrections play a crucial role throughout this thesis, we have also repeated the naive ansatz by replacing the free equilibrium propagator by propagators including thermal damping rates due to the Standard Model damping widths for lepton and Higgs fields. It is shown that this leads to a comparable result to the solutions of the Boltzmann equations for thermal leptogenesis. Thus it becomes obvious that Standard Model corrections are not negligible for thermal leptogenesis and therefore need to be included systematically from first principles. In order to achieve this we have started discussing the calculation of ladder rung diagrams for Majorana neutrinos using the HTL and the CTL approach in chapter 5. All gauge corrections are included in this framework and thus it has become the basis for the following considerations

  4. Low Temperature Plasma Medicine

    Science.gov (United States)

    Graves, David

    2013-10-01

    Ionized gas plasmas near room temperature are used in a remarkable number of technological applications mainly because they are extraordinarily efficient at exploiting electrical power for useful chemical and material transformations near room temperature. In this tutorial address, I will focus on the newest area of low temperature ionized gas plasmas (LTP), in this case operating under atmospheric pressure conditions, in which the temperature-sensitive material is living tissue. LTP research directed towards biomedical applications such as sterilization, surgery, wound healing and anti-cancer therapy has seen remarkable growth in the last 3-5 years, but the mechanisms responsible for the biomedical effects have remained mysterious. It is known that LTP readily create reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS (or RONS), in addition to a suite of other radical and non-radical reactive species, are essential actors in an important sub-field of aerobic biology termed ``redox'' (or oxidation-reduction) biology. I will review the evidence suggesting that RONS generated by plasmas are responsible for their observed therapeutic effects. Other possible bio-active mechanisms include electric fields, charges and photons. It is common in LTP applications that synergies between different mechanisms can play a role and I will review the evidence for synergies in plasma biomedicine. Finally, I will address the challenges and opportunities for plasma physicists to enter this novel, multidisciplinary field.

  5. The surgery of peripheral nerves (including tumors)

    DEFF Research Database (Denmark)

    Fugleholm, Kåre

    2013-01-01

    Surgical pathology of the peripheral nervous system includes traumatic injury, entrapment syndromes, and tumors. The recent significant advances in the understanding of the pathophysiology and cellular biology of peripheral nerve degeneration and regeneration has yet to be translated into improved...... surgical techniques and better outcome after peripheral nerve injury. Decision making in peripheral nerve surgery continues to be a complex challenge, where the mechanism of injury, repeated clinical evaluation, neuroradiological and neurophysiological examination, and detailed knowledge of the peripheral...... nervous system response to injury are prerequisite to obtain the best possible outcome. Surgery continues to be the primary treatment modality for peripheral nerve tumors and advances in adjuvant oncological treatment has improved outcome after malignant peripheral nerve tumors. The present chapter...

  6. AMS at the ANU including biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Fifield, L K; Allan, G L; Cresswell, R G; Ophel, T R [Australian National Univ., Canberra, ACT (Australia); King, S J; Day, J P [Manchester Univ. (United Kingdom). Dept. of Chemistry

    1994-12-31

    An extensive accelerator mass spectrometry program has been conducted on the 14UD accelerator at the Australian National University since 1986. In the two years since the previous conference, the research program has expanded significantly to include biomedical applications of {sup 26}Al and studies of landform evolution using isotopes produced in situ in surface rocks by cosmic ray bombardment. The system is now used for the measurement of {sup 10}Be, {sup 14}C, {sup 26}Al, {sup 36}Cl, {sup 59}Ni and {sup 129}I, and research is being undertaken in hydrology, environmental geochemistry, archaeology and biomedicine. On the technical side, a new test system has permitted the successful off-line development of a high-intensity ion source. A new injection line to the 14UD has been established and the new source is now in position and providing beams to the accelerator. 4 refs.

  7. AMS at the ANU including biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Fifield, L.K.; Allan, G.L.; Cresswell, R.G.; Ophel, T.R. [Australian National Univ., Canberra, ACT (Australia); King, S.J.; Day, J.P. [Manchester Univ. (United Kingdom). Dept. of Chemistry

    1993-12-31

    An extensive accelerator mass spectrometry program has been conducted on the 14UD accelerator at the Australian National University since 1986. In the two years since the previous conference, the research program has expanded significantly to include biomedical applications of {sup 26}Al and studies of landform evolution using isotopes produced in situ in surface rocks by cosmic ray bombardment. The system is now used for the measurement of {sup 10}Be, {sup 14}C, {sup 26}Al, {sup 36}Cl, {sup 59}Ni and {sup 129}I, and research is being undertaken in hydrology, environmental geochemistry, archaeology and biomedicine. On the technical side, a new test system has permitted the successful off-line development of a high-intensity ion source. A new injection line to the 14UD has been established and the new source is now in position and providing beams to the accelerator. 4 refs.

  8. CERN Technical Training: LABVIEW courses include RADE

    CERN Multimedia

    HR Department

    2009-01-01

    The contents of the "LabView Basic I" and "LabView Intermediate II" courses have recently been changed to include, respectively, an introduction to and expert training in the Rapid Application Development Environment (RADE). RADE is a LabView-based application developed at CERN to integrate LabView in the accelerator and experiment control infrastructure. It is a suitable solution to developing expert tools, machine development analysis and independent test facilities. The course names have also been changed to "LabVIEW Basics I with RADE Introduction" and "LabVIEW Intermediate II with Advanced RADE Application". " LabVIEW Basics I with RADE Introduction" is designed for: Users preparing to develop applications using LabVIEW, or NI Developer Suite; users and technical managers evaluating LabVIEW or NI Developer Suite in purchasing decisions; users pursuing the Certified LabVIEW Developer certification. The course pr...

  9. CERN Technical Training: LABVIEW courses include RADE

    CERN Multimedia

    HR Department

    2009-01-01

    The contents of the "LabView Basic I" and "LabView Intermediate II" courses have recently been changed to include, respectively, an introduction to and expert training in the Rapid Application Development Environment (RADE). RADE is a LabView-based application developed at CERN to integrate LabView in the accelerator and experiment control infrastructure. It is a suitable solution to developing expert tools, machine development analysis and independent test facilities. The course names have also been changed to "LabVIEW Basics I with RADE Introduction" and "LabVIEW Intermediate II with Advanced RADE Application". " LabVIEW Basics I with RADE Introduction" is designed for: Users preparing to develop applications using LabVIEW, or NI Developer Suite; users and technical managers evaluating LabVIEW or NI Developer Suite in purchasing decisions; users pursuing the Certified LabVIEW Developer certification. The course prepares participants to develop test and measurement, da...

  10. CERN Technical Training: LABVIEW courses include RADE

    CERN Multimedia

    HR Department

    2009-01-01

    The contents of "LabView Basic I" and "LabView Intermediate II" trainings have been recently changed to include, respectively, an introduction and an expert training on the Rapid Application Development Environment (RADE). RADE is a LabView-based application developed at CERN to integrate LabView in the accelerator and experiment control infrastructure. It is a suitable solution to develop expert tools, machine development analysis and independent test facilities. The course names have also been changed to "LabVIEW Basics I with RADE Introduction" and "LabVIEW Intermediate II with Advanced RADE Application". " LabVIEW Basics I with RADE Introduction" is designed for: Users preparing to develop applications using LabVIEW, or NI Developer Suite; users and technical managers evaluating LabVIEW or NI Developer Suite in purchasing decisions; users pursuing the Certified LabVIEW Developer certification. The course prepare...

  11. Critical point anomalies include expansion shock waves

    Energy Technology Data Exchange (ETDEWEB)

    Nannan, N. R., E-mail: ryan.nannan@uvs.edu [Mechanical Engineering Discipline, Anton de Kom University of Suriname, Leysweg 86, PO Box 9212, Paramaribo, Suriname and Process and Energy Department, Delft University of Technology, Leeghwaterstraat 44, 2628 CA Delft (Netherlands); Guardone, A., E-mail: alberto.guardone@polimi.it [Department of Aerospace Science and Technology, Politecnico di Milano, Via La Masa 34, 20156 Milano (Italy); Colonna, P., E-mail: p.colonna@tudelft.nl [Propulsion and Power, Delft University of Technology, Kluyverweg 1, 2629 HS Delft (Netherlands)

    2014-02-15

    From first-principle fluid dynamics, complemented by a rigorous state equation accounting for critical anomalies, we discovered that expansion shock waves may occur in the vicinity of the liquid-vapor critical point in the two-phase region. Due to universality of near-critical thermodynamics, the result is valid for any common pure fluid in which molecular interactions are only short-range, namely, for so-called 3-dimensional Ising-like systems, and under the assumption of thermodynamic equilibrium. In addition to rarefaction shock waves, diverse non-classical effects are admissible, including composite compressive shock-fan-shock waves, due to the change of sign of the fundamental derivative of gasdynamics.

  12. CLIC expands to include the Southern Hemisphere

    CERN Multimedia

    Roberto Cantoni

    2010-01-01

    Australia has recently joined the CLIC collaboration: the enlargement will bring new expertise and resources to the project, and is especially welcome in the wake of CERN budget redistributions following the recent adoption of the Medium Term Plan.   The countries involved in CLIC collaboration With the signing of a Memorandum of Understanding on 26 August 2010, the ACAS network (Australian Collaboration for Accelerator Science) became the 40th member of in the multilateral CLIC collaboration making Australia the 22nd country to join the collaboration. “The new MoU was signed by the ACAS network, which includes the Australian Synchrotron and the University of Melbourne”, explains Jean-Pierre Delahaye, CLIC Study Leader. “Thanks to their expertise, the Australian institutes will contribute greatly to the CLIC damping rings and the two-beam test modules." Institutes from any country wishing to join the CLIC collaboration are invited to assume responsibility o...

  13. Should Broca's area include Brodmann area 47?

    Science.gov (United States)

    Ardila, Alfredo; Bernal, Byron; Rosselli, Monica

    2017-02-01

    Understanding brain organization of speech production has been a principal goal of neuroscience. Historically, brain speech production has been associated with so-called Broca’s area (Brodmann area –BA- 44 and 45), however, modern neuroimaging developments suggest speech production is associated with networks rather than with areas. The purpose of this paper was to analyze the connectivity of BA47 ( pars orbitalis) in relation to language . A meta-analysis was conducted to assess the language network in which BA47 is involved. The Brainmap database was used. Twenty papers corresponding to 29 experimental conditions with a total of 373 subjects were included. Our results suggest that BA47 participates in a “frontal language production system” (or extended Broca’s system). The BA47  connectivity found is also concordant with a minor role in language semantics. BA47 plays a central role in the language production system.

  14. Musculoskeletal ultrasound including definitions for ultrasonographic pathology

    DEFF Research Database (Denmark)

    Wakefield, RJ; Balint, PV; Szkudlarek, Marcin

    2005-01-01

    Ultrasound (US) has great potential as an outcome in rheumatoid arthritis trials for detecting bone erosions, synovitis, tendon disease, and enthesopathy. It has a number of distinct advantages over magnetic resonance imaging, including good patient tolerability and ability to scan multiple joints...... in a short period of time. However, there are scarce data regarding its validity, reproducibility, and responsiveness to change, making interpretation and comparison of studies difficult. In particular, there are limited data describing standardized scanning methodology and standardized definitions of US...... pathologies. This article presents the first report from the OMERACT ultrasound special interest group, which has compared US against the criteria of the OMERACT filter. Also proposed for the first time are consensus US definitions for common pathological lesions seen in patients with inflammatory arthritis....

  15. Grand unified models including extra Z bosons

    International Nuclear Information System (INIS)

    Li Tiezhong

    1989-01-01

    The grand unified theories (GUT) of the simple Lie groups including extra Z bosons are discussed. Under authors's hypothesis there are only SU 5+m SO 6+4n and E 6 groups. The general discussion of SU 5+m is given, then the SU 6 and SU 7 are considered. In SU 6 the 15+6 * +6 * fermion representations are used, which are not same as others in fermion content, Yukawa coupling and broken scales. A conception of clans of particles, which are not families, is suggested. These clans consist of extra Z bosons and the corresponding fermions of the scale. The all of fermions in the clans are down quarks except for the standard model which consists of Z bosons and 15 fermions, therefore, the spectrum of the hadrons which are composed of these down quarks are different from hadrons at present

  16. Including climate change in energy investment decisions

    International Nuclear Information System (INIS)

    Ybema, J.R.; Boonekamp, P.G.M.; Smit, J.T.J.

    1995-08-01

    To properly take climate change into account in the analysis of energy investment decisions, it is required to apply decision analysis methods that are capable of considering the specific characteristics of climate change (large uncertainties, long term horizon). Such decision analysis methods do exist. They can explicitly include evolving uncertainties, multi-stage decisions, cumulative effects and risk averse attitudes. Various methods are considered in this report and two of these methods have been selected: hedging calculations and sensitivity analysis. These methods are applied to illustrative examples, and its limitations are discussed. The examples are (1a) space heating and hot water for new houses from a private investor perspective and (1b) as example (1a) but from a government perspective, (2) electricity production with an integrated coal gasification combined cycle (ICGCC) with or without CO 2 removal, and (3) national energy strategy to hedge for climate change. 9 figs., 21 tabs., 42 refs., 1 appendix

  17. Education Program on Fossil Resources Including Coal

    Science.gov (United States)

    Usami, Masahiro

    Fossil fuels including coal play a key role as crucial energies in contributing to economic development in Asia. On the other hand, its limited quantity and the environmental problems causing from its usage have become a serious global issue and a countermeasure to solve such problems is very much demanded. Along with the pursuit of sustainable development, environmentally-friendly use of highly efficient fossil resources should be therefore, accompanied. Kyushu-university‧s sophisticated research through long years of accumulated experience on the fossil resources and environmental sectors together with the advanced large-scale commercial and empirical equipments will enable us to foster cooperative research and provide internship program for the future researchers. Then, this program is executed as a consignment business from the Ministry of Economy, Trade and Industry from 2007 fiscal year to 2009 fiscal year. The lecture that uses the textbooks developed by this program is scheduled to be started a course in fiscal year 2010.

  18. Analysis of Smart Composite Structures Including Debonding

    Science.gov (United States)

    Chattopadhyay, Aditi; Seeley, Charles E.

    1997-01-01

    Smart composite structures with distributed sensors and actuators have the capability to actively respond to a changing environment while offering significant weight savings and additional passive controllability through ply tailoring. Piezoelectric sensing and actuation of composite laminates is the most promising concept due to the static and dynamic control capabilities. Essential to the implementation of these smart composites are the development of accurate and efficient modeling techniques and experimental validation. This research addresses each of these important topics. A refined higher order theory is developed to model composite structures with surface bonded or embedded piezoelectric transducers. These transducers are used as both sensors and actuators for closed loop control. The theory accurately captures the transverse shear deformation through the thickness of the smart composite laminate while satisfying stress free boundary conditions on the free surfaces. The theory is extended to include the effect of debonding at the actuator-laminate interface. The developed analytical model is implemented using the finite element method utilizing an induced strain approach for computational efficiency. This allows general laminate geometries and boundary conditions to be analyzed. The state space control equations are developed to allow flexibility in the design of the control system. Circuit concepts are also discussed. Static and dynamic results of smart composite structures, obtained using the higher order theory, are correlated with available analytical data. Comparisons, including debonded laminates, are also made with a general purpose finite element code and available experimental data. Overall, very good agreement is observed. Convergence of the finite element implementation of the higher order theory is shown with exact solutions. Additional results demonstrate the utility of the developed theory to study piezoelectric actuation of composite

  19. Zγ production at NNLO including anomalous couplings

    Science.gov (United States)

    Campbell, John M.; Neumann, Tobias; Williams, Ciaran

    2017-11-01

    In this paper we present a next-to-next-to-leading order (NNLO) QCD calculation of the processes pp → l + l -γ and pp\\to ν \\overline{ν}γ that we have implemented in MCFM. Our calculation includes QCD corrections at NNLO both for the Standard Model (SM) and additionally in the presence of Zγγ and ZZγ anomalous couplings. We compare our implementation, obtained using the jettiness slicing approach, with a previous SM calculation and find broad agreement. Focusing on the sensitivity of our results to the slicing parameter, we show that using our setup we are able to compute NNLO cross sections with numerical uncertainties of about 0.1%, which is small compared to residual scale uncertainties of a few percent. We study potential improvements using two different jettiness definitions and the inclusion of power corrections. At √{s}=13 TeV we present phenomenological results and consider Zγ as a background to H → Zγ production. We find that, with typical cuts, the inclusion of NNLO corrections represents a small effect and loosens the extraction of limits on anomalous couplings by about 10%.

  20. Alternating phase focussing including space charge

    International Nuclear Information System (INIS)

    Cheng, W.H.; Gluckstern, R.L.

    1992-01-01

    Longitudinal stability can be obtained in a non-relativistic drift tube accelerator by traversing each gap as the rf accelerating field rises. However, the rising accelerating field leads to a transverse defocusing force which is usually overcome by magnetic focussing inside the drift tubes. The radio frequency quadrupole is one way of providing simultaneous longitudinal and transverse focusing without the use of magnets. One can also avoid the use of magnets by traversing alternate gaps between drift tubes as the field is rising and falling, thus providing an alternation of focussing and defocusing forces in both the longitudinal and transverse directions. The stable longitudinal phase space area is quite small, but recent efforts suggest that alternating phase focussing (APF) may permit low velocity acceleration of currents in the 100-300 ma range. This paper presents a study of the parameter space and a test of crude analytic predictions by adapting the code PARMILA, which includes space charge, to APF. 6 refs., 3 figs

  1. Probabilistic production simulation including CHP plants

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, H.V.; Palsson, H.; Ravn, H.F.

    1997-04-01

    A probabilistic production simulation method is presented for an energy system containing combined heat and power plants. The method permits incorporation of stochastic failures (forced outages) of the plants and is well suited for analysis of the dimensioning of the system, that is, for finding the appropriate types and capacities of production plants in relation to expansion planning. The method is in the tradition of similar approaches for the analysis of power systems, based on the load duration curve. The present method extends on this by considering a two-dimensional load duration curve where the two dimensions represent heat and power. The method permits the analysis of a combined heat and power system which includes all the basic relevant types of plants, viz., condensing plants, back pressure plants, extraction plants and heat plants. The focus of the method is on the situation where the heat side has priority. This implies that on the power side there may be imbalances between demand and production. The method permits quantification of the expected power overflow, the expected unserviced power demand, and the expected unserviced heat demand. It is shown that a discretization method as well as double Fourier series may be applied in algorithms based on the method. (au) 1 tab., 28 ills., 21 refs.

  2. Langevin simulations of QCD, including fermions

    International Nuclear Information System (INIS)

    Kronfeld, A.S.

    1986-02-01

    We encounter critical slow down in updating when xi/a -> infinite and in matrix inversion (needed to include fermions) when msub(q)a -> 0. A simulation that purports to solve QCD numerically will encounter these limits, so to face the challenge in the title of this workshop, we must cure the disease of critical slow down. Physically, this critical slow down is due to the reluctance of changes at short distances to propagate to large distances. Numerically, the stability of an algorithm at short wavelengths requires a (moderately) small step size; critical slow down occurs when the effective long wavelength step size becomes tiny. The remedy for this disease is an algorithm that propagates signals quickly throughout the system; i.e. one whose effective step size is not reduced for the long wavelength conponents of the fields. (Here the effective ''step size'' is essentially an inverse decorrelation time.) To do so one must resolve various wavelengths of the system and modify the dynamics (in CPU time) of the simulation so that all modes evolve at roughly the same rate. This can be achieved by introducing Fourier transforms. I show how to implement Fourier acceleration for Langevin updating and for conjugate gradient matrix inversion. The crucial feature of these algorithms that lends them to Fourier acceleration is that they update the lattice globally; hence the Fourier transforms are computed once per sweep rather than once per hit. (orig./HSI)

  3. SEEPAGE MODEL FOR PA INCLUDING DRIFT COLLAPSE

    International Nuclear Information System (INIS)

    C. Tsang

    2004-01-01

    The purpose of this report is to document the predictions and analyses performed using the seepage model for performance assessment (SMPA) for both the Topopah Spring middle nonlithophysal (Tptpmn) and lower lithophysal (Tptpll) lithostratigraphic units at Yucca Mountain, Nevada. Look-up tables of seepage flow rates into a drift (and their uncertainty) are generated by performing numerical simulations with the seepage model for many combinations of the three most important seepage-relevant parameters: the fracture permeability, the capillary-strength parameter 1/a, and the percolation flux. The percolation flux values chosen take into account flow focusing effects, which are evaluated based on a flow-focusing model. Moreover, multiple realizations of the underlying stochastic permeability field are conducted. Selected sensitivity studies are performed, including the effects of an alternative drift geometry representing a partially collapsed drift from an independent drift-degradation analysis (BSC 2004 [DIRS 166107]). The intended purpose of the seepage model is to provide results of drift-scale seepage rates under a series of parameters and scenarios in support of the Total System Performance Assessment for License Application (TSPA-LA). The SMPA is intended for the evaluation of drift-scale seepage rates under the full range of parameter values for three parameters found to be key (fracture permeability, the van Genuchten 1/a parameter, and percolation flux) and drift degradation shape scenarios in support of the TSPA-LA during the period of compliance for postclosure performance [Technical Work Plan for: Performance Assessment Unsaturated Zone (BSC 2002 [DIRS 160819], Section I-4-2-1)]. The flow-focusing model in the Topopah Spring welded (TSw) unit is intended to provide an estimate of flow focusing factors (FFFs) that (1) bridge the gap between the mountain-scale and drift-scale models, and (2) account for variability in local percolation flux due to

  4. Engine Cylinder Temperature Control

    Science.gov (United States)

    Kilkenny, Jonathan Patrick; Duffy, Kevin Patrick

    2005-09-27

    A method and apparatus for controlling a temperature in a combustion cylinder in an internal combustion engine. The cylinder is fluidly connected to an intake manifold and an exhaust manifold. The method and apparatus includes increasing a back pressure associated with the exhaust manifold to a level sufficient to maintain a desired quantity of residual exhaust gas in the cylinder, and varying operation of an intake valve located between the intake manifold and the cylinder to an open duration sufficient to maintain a desired quantity of fresh air from the intake manifold to the cylinder, wherein controlling the quantities of residual exhaust gas and fresh air are performed to maintain the temperature in the cylinder at a desired level.

  5. The early warning system of landslides and sediment runoffs using meteorological condition including rainfall-soil moisture index (Invited)

    Science.gov (United States)

    Kubota, T.; Silva, I. C.; Hasnawir, H.

    2009-12-01

    The research including observation of rain, soil moisture content and sediment discharge is conducted on a torrent in northern Kyushu whose geology consists of Paleozoic metamorphic rocks (mainly schist) and whose vegetation consists of mainly Japanese cypress and cedar. Soil depth is approximately 50cm in average and permeability k is 0.1~0.01 order. With data obtained by the observation for more than 4 years, standard rainfalls of warning and evacuation against the sudden sediment runoffs are analyzed. Then, the result was compared with the ones in Nuevo Leon Mexico (geology of schist, slate, k=0.01~0.001 order) and in southern Sulawesi Island Indonesia (volcanic geology, k=0.001~0.0001 order). Hitherto, various methods were proposed to analyze the warning critical standard for landslide disaster or large sediment discharge. In this study, we employed Hirano's element slope runoff theory, the Self Organized Criticality Assumption (SOC), and the Elementary Catastrophe Theory (ETC) to analyze the data, although the soil moisture fluctuation, meteorological condition such as upper air wind and dew point depression, the rainfall-soil moisture index provided by Japan Meteorological Agency was considered. The last one is a cutting edge technology based on the tank model calculation of soil moisture content combined with short term rainfall prediction which is a product of numerical simulation using radar image advection analysis compensated with surface rain data and with orographic rain effect. In Hirano's theory, we can describe the critical rain Rc and rain intensity Ric as following equation. Q/A/M/ cosθ = Ri ∫(r*cosθ)dt = Ri*R (1) ∴ Ric*Rc = C (2) Here, Q: sediment runoff or debris flow discharge, A: watershed area, M: function concerning with sediment deposit features on the upstream torrents or slopes (porosity, torrent bed slope gradient, sediment accumulation length and depth, cohesion), t: time, θ: torrent bed or hillside slope gradient, r: instant

  6. Managing Temperature Effects in Nanoscale Adaptive Systems

    CERN Document Server

    Wolpert, David

    2012-01-01

    This book discusses new techniques for detecting, controlling, and exploiting the impacts of temperature variations on nanoscale circuits and systems.  It provides a holistic discussion of temperature management, including physical phenomena (reversal of the MOSFET temperature dependence) that have recently become problematic, along with circuit techniques for detecting, controlling, and adapting to these phenomena. A detailed discussion is also included of the general aspects of thermal-aware system design and management of temperature-induced faults. A new sensor system is described that can determine the temperature dependence as well as the operating temperature to improve system reliability.  A new method is presented to control a circuit’s temperature dependence by individually tuning pull-up and pull-down networks to their temperature-insensitive operating points. This method extends the range of supply voltages that can be made temperature-insensitive, achieving insensitivity at nominal voltage fo...

  7. A method for high accuracy determination of equilibrium relative humidity

    DEFF Research Database (Denmark)

    Jensen, O.M.

    2012-01-01

    This paper treats a new method for measuring equilibrium relative humidity and equilibrium dew-point temperature of a material sample. The developed measuring device is described – a Dew-point Meter – which by means of so-called Dynamic Dew-point Analysis permits quick and very accurate...

  8. Modeling daily soil temperature over diverse climate conditions in Iran—a comparison of multiple linear regression and support vector regression techniques

    Science.gov (United States)

    Delbari, Masoomeh; Sharifazari, Salman; Mohammadi, Ehsan

    2018-02-01

    The knowledge of soil temperature at different depths is important for agricultural industry and for understanding climate change. The aim of this study is to evaluate the performance of a support vector regression (SVR)-based model in estimating daily soil temperature at 10, 30 and 100 cm depth at different climate conditions over Iran. The obtained results were compared to those obtained from a more classical multiple linear regression (MLR) model. The correlation sensitivity for the input combinations and periodicity effect were also investigated. Climatic data used as inputs to the models were minimum and maximum air temperature, solar radiation, relative humidity, dew point, and the atmospheric pressure (reduced to see level), collected from five synoptic stations Kerman, Ahvaz, Tabriz, Saghez, and Rasht located respectively in the hyper-arid, arid, semi-arid, Mediterranean, and hyper-humid climate conditions. According to the results, the performance of both MLR and SVR models was quite well at surface layer, i.e., 10-cm depth. However, SVR performed better than MLR in estimating soil temperature at deeper layers especially 100 cm depth. Moreover, both models performed better in humid climate condition than arid and hyper-arid areas. Further, adding a periodicity component into the modeling process considerably improved the models' performance especially in the case of SVR.

  9. An Integrated Biochemistry Laboratory, Including Molecular Modeling

    Science.gov (United States)

    Hall, Adele J. Wolfson Mona L.; Branham, Thomas R.

    1996-11-01

    The dilemma of designing an advanced undergraduate laboratory lies in the desire to teach and reinforce basic principles and techniques while at the same time exposing students to the excitement of research. We report here on a one-semester, project-based biochemistry laboratory that combines the best features of a cookbook approach (high success rate, achievement of defined goals) with those of an investigative, discovery-based approach (student involvement in the experimental design, excitement of real research). Individual modules may be selected and combined to meet the needs of different courses and different institutions. The central theme of this lab is protein purification and design. This laboratory accompanies the first semester of biochemistry (Structure and Function of Macromolecules, a course taken mainly by junior and senior chemistry and biological chemistry majors). The protein chosen as the object of study is the enzyme lysozyme, which is utilized in all projects. It is suitable for a student lab because it is easily and inexpensively obtained from egg white and is extremely stable, and its high isoelectric point (pI = 11) allows for efficient separation from other proteins by ion-exchange chromatography. Furthermore, a literature search conducted by the resourceful student reveals a wealth of information, since lysozyme has been the subject of numerous studies. It was the first enzyme whose structure was determined by crystallography (1). Hendrickson et al. (2) have previously described an intensive one-month laboratory course centered around lysozyme, although their emphasis is on protein stability rather than purification and engineering. Lysozyme continues to be the focus of much exciting new work on protein folding and dynamics, structure and activity (3 - 5). This lab course includes the following features: (i) reinforcement of basic techniques, such as preparation of buffers, simple enzyme kinetics, and absorption spectroscopy; (ii

  10. Densities and apparent molar volumes of atmospherically important electrolyte solutions. 1. The solutes H2SO4, HNO3, HCl, Na2SO4, NaNO3, NaCl, (NH4)2SO4, NH4NO3, and NH4Cl from 0 to 50 °C, including extrapolations to very low temperature and to the pure liquid state, and NaHSO4, NaOH, and NH3 at 25 °C.

    Science.gov (United States)

    Clegg, S L; Wexler, A S

    2011-04-21

    Calculations of the size and density of atmospheric aerosols are complicated by the fact that they can exist at concentrations highly supersaturated with respect to dissolved salts and supercooled with respect to ice. Densities and apparent molar volumes of solutes in aqueous solutions containing the solutes H(2)SO(4), HNO(3), HCl, Na(2)SO(4), NaNO(3), NaCl, (NH(4))(2)SO(4), NH(4)NO(3), and NH(4)Cl have been critically evaluated and represented using fitted equations from 0 to 50 °C or greater and from infinite dilution to concentrations saturated or supersaturated with respect to the dissolved salts. Using extrapolated densities of high-temperature solutions and melts, the relationship between density and concentration is extended to the hypothetical pure liquid solutes. Above a given reference concentration of a few mol kg(-1), it is observed that density increases almost linearly with decreasing temperature, and comparisons with available data below 0 °C suggest that the fitted equations for density can be extrapolated to very low temperatures. As concentration is decreased below the reference concentration, the variation of density with temperature tends to that of water (which decreases as temperature is reduced below 3.98 °C). In this region below the reference concentration, and below 0 °C, densities are calculated using extrapolated apparent molar volumes which are constrained to agree at the reference concentrations with an equation for the directly fitted density. Calculated volume properties agree well with available data at low temperatures, for both concentrated and dilute solutions. Comparisons are made with literature data for temperatures of maximum density. Apparent molar volumes at infinite dilution are consistent, on a single ion basis, to better than ±0.1 cm(3) mol(-1) from 0 to 50 °C. Volume properties of aqueous NaHSO(4), NaOH, and NH(3) have also been evaluated, at 25 °C only. In part 2 of this work (ref 1 ) an ion interaction (Pitzer

  11. High temperature superconductors

    CERN Document Server

    Paranthaman, Parans

    2010-01-01

    This essential reference provides the most comprehensive presentation of the state of the art in the field of high temperature superconductors. This growing field of research and applications is currently being supported by numerous governmental and industrial initiatives in the United States, Asia and Europe to overcome grid energy distribution issues. The technology is particularly intended for densely populated areas. It is now being commercialized for power-delivery devices, such as power transmission lines and cables, motors and generators. Applications in electric utilities include current limiters, long transmission lines and energy-storage devices that will help industries avoid dips in electric power.

  12. The Microwave Temperature Profiler (PERF)

    Science.gov (United States)

    Lim, Boon; Mahoney, Michael; Haggerty, Julie; Denning, Richard

    2013-01-01

    The JPL developed Microwave Temperature Profiler (MTP) has recently participated in GloPac, HIPPO (I to V) and TORERO, and the ongoing ATTREX campaigns. The MTP is now capable of supporting the NASA Global Hawk and a new canister version supports the NCAR G-V. The primary product from the MTP is remote measurements of the atmospheric temperature at, above and below the flight path, providing for the vertical state of the atmosphere. The NCAR-MTP has demonstrated unprecedented instrument performance and calibration with plus or minus 0.2 degrees Kelvin flight level temperature error. Derived products include curtain plots, isentropes, lapse rate, cold point height and tropopause height.

  13. High temperature materials

    International Nuclear Information System (INIS)

    2003-01-01

    The aim of this workshop is to share the needs of high temperature and nuclear fuel materials for future nuclear systems, to take stock of the status of researches in this domain and to propose some cooperation works between the different research organisations. The future nuclear systems are the very high temperature (850 to 1200 deg. C) gas cooled reactors (GCR) and the molten salt reactors (MSR). These systems include not only the reactor but also the fabrication and reprocessing of the spent fuel. This document brings together the transparencies of 13 communications among the 25 given at the workshop: 1) characteristics and needs of future systems: specifications, materials and fuel needs for fast spectrum GCR and very high temperature GCR; 2) high temperature materials out of neutron flux: thermal barriers: materials, resistance, lifetimes; nickel-base metal alloys: status of knowledge, mechanical behaviour, possible applications; corrosion linked with the gas coolant: knowledge and problems to be solved; super-alloys for turbines: alloys for blades and discs; corrosion linked with MSR: knowledge and problems to be solved; 3) materials for reactor core structure: nuclear graphite and carbon; fuel assembly structure materials of the GCR with fast neutron spectrum: status of knowledge and ceramics and cermets needs; silicon carbide as fuel confinement material, study of irradiation induced defects; migration of fission products, I and Cs in SiC; 4) materials for hydrogen production: status of the knowledge and needs for the thermochemical cycle; 5) technologies: GCR components and the associated material needs: compact exchangers, pumps, turbines; MSR components: valves, exchangers, pumps. (J.S.)

  14. Ionic liquids, electrolyte solutions including the ionic liquids, and energy storage devices including the ionic liquids

    Science.gov (United States)

    Gering, Kevin L.; Harrup, Mason K.; Rollins, Harry W.

    2015-12-08

    An ionic liquid including a phosphazene compound that has a plurality of phosphorus-nitrogen units and at least one pendant group bonded to each phosphorus atom of the plurality of phosphorus-nitrogen units. One pendant group of the at least one pendant group comprises a positively charged pendant group. Additional embodiments of ionic liquids are disclosed, as are electrolyte solutions and energy storage devices including the embodiments of the ionic liquid.

  15. Body temperature norms

    Science.gov (United States)

    Normal body temperature; Temperature - normal ... Morrison SF. Regulation of body temperature. In: Boron WF, Boulpaep EL, eds. Medical Physiology . 3rd ed. Philadelphia, PA: Elsevier; 2017:chap 59. Sajadi MM, Mackowiak ...

  16. Magnetic properties of nickel halide hydrates including deuteration effects

    Energy Technology Data Exchange (ETDEWEB)

    DeFotis, G.C., E-mail: gxdefo@wm.edu [Chemistry Department, College of William & Mary, Williamsburg, VA, 23187 United States (United States); Van Dongen, M.J.; Hampton, A.S.; Komatsu, C.H.; Trowell, K.T.; Havas, K.C.; Davis, C.M.; DeSanto, C.L. [Chemistry Department, College of William & Mary, Williamsburg, VA, 23187 United States (United States); Hays, K.; Wagner, M.J. [Chemistry Department, George Washington University, Washington, DC, 20052 United States (United States)

    2017-01-01

    Magnetic measurements on variously hydrated nickel chlorides and bromides, including deuterated forms, are reported. Results include locations and sizes of susceptibility maxima, T{sub max} and χ{sub max}, ordering temperatures T{sub c}, Curie constants and Weiss theta in the paramagnetic regime, and primary and secondary exchange interactions from analysis of low temperature data. For the latter a 2D Heisenberg model augmented by interlayer exchange in a mean-field approximation is applied. Magnetization data to 16 kG as a function of temperature show curvature and hysteresis characteristics quite system dependent. For four materials high field magnetization data to 70 kG at 2.00 K are also obtained. Comparison is made with theoretical relations for spin-1 models. Trends are apparent, primarily that T{sub max} of each bromide hydrate is less than for the corresponding chloride, and that for a given halide nD{sub 2}O (n=1 or 2) deuterates exhibit lesser T{sub max} than do nH{sub 2}O hydrates. A monoclinic unit cell determined from powder X-ray diffraction data on NiBr{sub 2}·2D{sub 2}O is different from and slightly larger than that of NiBr{sub 2}·2H{sub 2}O. This provides some rationale for the difference in magnetic properties between these. - Highlights: • The magnetism of Ni(II) chloride and bromide dihydrates and monohydrates is studied. • Effects of replacing H{sub 2}O by D{sub 2}O are examined for both hydration states and both halides. • Exchange interactions in bromides are weaker than in corresponding chlorides. • Exchange interactions are weaker in D{sub 2}O than in corresponding H{sub 2}O containing systems. • The unit cell of NiBr{sub 2}·2D{sub 2}O is different from and slightly larger than that of NiBr{sub 2}·2H{sub 2}O.

  17. Carbon nanotube temperature and pressure sensors

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Ilia N.; Geohegan, David B.

    2017-09-12

    The present invention, in one embodiment, provides a method of measuring pressure or temperature using a sensor including a sensor element composed of a plurality of carbon nanotubes. In one example, the resistance of the plurality of carbon nanotubes is measured in response to the application of temperature or pressure. The changes in resistance are then recorded and correlated to temperature or pressure. In one embodiment, the present invention provides for independent measurement of pressure or temperature using the sensors disclosed herein.

  18. Carbon nanotube temperature and pressure sensors

    Science.gov (United States)

    Ivanov, Ilia N; Geohegan, David Bruce

    2013-10-29

    The present invention, in one embodiment, provides a method of measuring pressure or temperature using a sensor including a sensor element composed of a plurality of carbon nanotubes. In one example, the resistance of the plurality of carbon nanotubes is measured in response to the application of temperature or pressure. The changes in resistance are then recorded and correlated to temperature or pressure. In one embodiment, the present invention provides for independent measurement of pressure or temperature using the sensors disclosed herein.

  19. The Climatology Module CLIMAT

    National Research Council Canada - National Science Library

    Avara, Elton

    1998-01-01

    ... (temperature, dew point temperature, absolute humidity, relative humidity, horizontal visibility, sea level pressure, wind speed, wind direction, cloudbase height, cloud cover, and Pasquill stability category...

  20. Analysis of a resistance-energy balance method for estimating daily evaporation from wheat plots using one-time-of-day infrared temperature observations

    Science.gov (United States)

    Choudhury, B. J.; Idso, S. B.; Reginato, R. J.

    1986-01-01

    Accurate estimates of evaporation over field-scale or larger areas are needed in hydrologic studies, irrigation scheduling, and meteorology. Remotely sensed surface temperature might be used in a model to calculate evaporation. A resistance-energy balance model, which combines an energy balance equation, the Penman-Monteith (1981) evaporation equation, and van den Honert's (1948) equation for water extraction by plant roots, is analyzed for estimating daily evaporation from wheat using postnoon canopy temperature measurements. Additional data requirements are half-hourly averages of solar radiation, air and dew point temperatures, and wind speed, along with reasonable estimates of canopy emissivity, albedo, height, and leaf area index. Evaporation fluxes were measured in the field by precision weighing lysimeters for well-watered and water-stressed wheat. Errors in computed daily evaporation were generally less than 10 percent, while errors in cumulative evaporation for 10 clear sky days were less than 5 percent for both well-watered and water-stressed wheat. Some results from sensitivity analysis of the model are also given.

  1. The Kelvin and Temperature Measurements

    Science.gov (United States)

    Mangum, B. W.; Furukawa, G. T.; Kreider, K. G.; Meyer, C. W.; Ripple, D. C.; Strouse, G. F.; Tew, W. L.; Moldover, M. R.; Johnson, B. Carol; Yoon, H. W.; Gibson, C. E.; Saunders, R. D.

    2001-01-01

    The International Temperature Scale of 1990 (ITS-90) is defined from 0.65 K upwards to the highest temperature measurable by spectral radiation thermometry, the radiation thermometry being based on the Planck radiation law. When it was developed, the ITS-90 represented thermodynamic temperatures as closely as possible. Part I of this paper describes the realization of contact thermometry up to 1234.93 K, the temperature range in which the ITS-90 is defined in terms of calibration of thermometers at 15 fixed points and vapor pressure/temperature relations which are phase equilibrium states of pure substances. The realization is accomplished by using fixed-point devices, containing samples of the highest available purity, and suitable temperature-controlled environments. All components are constructed to achieve the defining equilibrium states of the samples for the calibration of thermometers. The high quality of the temperature realization and measurements is well documented. Various research efforts are described, including research to improve the uncertainty in thermodynamic temperatures by measuring the velocity of sound in gas up to 800 K, research in applying noise thermometry techniques, and research on thermocouples. Thermometer calibration services and high-purity samples and devices suitable for “on-site” thermometer calibration that are available to the thermometry community are described. Part II of the paper describes the realization of temperature above 1234.93 K for which the ITS-90 is defined in terms of the calibration of spectroradiometers using reference blackbody sources that are at the temperature of the equilibrium liquid-solid phase transition of pure silver, gold, or copper. The realization of temperature from absolute spectral or total radiometry over the temperature range from about 60 K to 3000 K is also described. The dissemination of the temperature scale using radiation thermometry from NIST to the customer is achieved by

  2. Catalyst support structure, catalyst including the structure, reactor including a catalyst, and methods of forming same

    Science.gov (United States)

    Van Norman, Staci A.; Aston, Victoria J.; Weimer, Alan W.

    2017-05-09

    Structures, catalysts, and reactors suitable for use for a variety of applications, including gas-to-liquid and coal-to-liquid processes and methods of forming the structures, catalysts, and reactors are disclosed. The catalyst material can be deposited onto an inner wall of a microtubular reactor and/or onto porous tungsten support structures using atomic layer deposition techniques.

  3. Study on 'Tannix' an absorbent for heavy metals including uranium

    International Nuclear Information System (INIS)

    Nakamura, Yasuo

    1997-01-01

    To treat radioactive wastes including uranium and transuranic elements such as plutonium, americium etc., development of an absorbent which can be used to absorb and isolate these elements without producing secondary wastes after treatment was attempted. And an absorbent has been successfully developed by polymerizing tannin, a natural product. It is known that tannin binds heavy metals including uranium resulting to produce their precipitates. There are some reports suggesting its absorption ability for uranium. However, tannin has not been used to isolate a heavy metal from a solution because it is soluble in water. Here, insolubilization of tannin was attempted and a manufacturing method for a gelatinized insoluble tannin named as ''Tannix'' was established. Wattle tannin extracted from Mimosa pudica produced in Africa was dissolved in an alkaline solution and gelatinized by heating after the addition of formalin. Thus obtained insoluble tannin was used after crushing and sieving. This product, ''Tannix'' was able to absorb more than 99% of uranium in the waste. And the absorbed Tannin could be degraded by incineration even at a low temperature, leaving only uranium, but not producing any secondary product. (M.N.)

  4. Study on `Tannix` an absorbent for heavy metals including uranium

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Yasuo [Mitsubishi Nuclear Fuel Co. Ltd., Tokyo (Japan)

    1997-09-01

    To treat radioactive wastes including uranium and transuranic elements such as plutonium, americium etc., development of an absorbent which can be used to absorb and isolate these elements without producing secondary wastes after treatment was attempted. And an absorbent has been successfully developed by polymerizing tannin, a natural product. It is known that tannin binds heavy metals including uranium resulting to produce their precipitates. There are some reports suggesting its absorption ability for uranium. However, tannin has not been used to isolate a heavy metal from a solution because it is soluble in water. Here, insolubilization of tannin was attempted and a manufacturing method for a gelatinized insoluble tannin named as ``Tannix`` was established. Wattle tannin extracted from Mimosa pudica produced in Africa was dissolved in an alkaline solution and gelatinized by heating after the addition of formalin. Thus obtained insoluble tannin was used after crushing and sieving. This product, ``Tannix`` was able to absorb more than 99% of uranium in the waste. And the absorbed Tannin could be degraded by incineration even at a low temperature, leaving only uranium, but not producing any secondary product. (M.N.)

  5. Deep Trek High Temperature Electronics Project

    Energy Technology Data Exchange (ETDEWEB)

    Bruce Ohme

    2007-07-31

    This report summarizes technical progress achieved during the cooperative research agreement between Honeywell and U.S. Department of Energy to develop high-temperature electronics. Objects of this development included Silicon-on-Insulator (SOI) wafer process development for high temperature, supporting design tools and libraries, and high temperature integrated circuit component development including FPGA, EEPROM, high-resolution A-to-D converter, and a precision amplifier.

  6. Launch Lock Assemblies Including Axial Gap Amplification Devices and Spacecraft Isolation Systems Including the Same

    Science.gov (United States)

    Barber, Tim Daniel (Inventor); Hindle, Timothy (Inventor); Young, Ken (Inventor); Davis, Torey (Inventor)

    2014-01-01

    Embodiments of a launch lock assembly are provided, as are embodiments of a spacecraft isolation system including one or more launch lock assemblies. In one embodiment, the launch lock assembly includes first and second mount pieces, a releasable clamp device, and an axial gap amplification device. The releasable clamp device normally maintains the first and second mount pieces in clamped engagement; and, when actuated, releases the first and second mount pieces from clamped engagement to allow relative axial motion there between. The axial gap amplification device normally residing in a blocking position wherein the gap amplification device obstructs relative axial motion between the first and second mount pieces. The axial gap amplification device moves into a non-blocking position when the first and second mount pieces are released from clamped engagement to increase the range of axial motion between the first and second mount pieces.

  7. GlobTemperature

    Science.gov (United States)

    Ghent, Darren; Remedios, John; Bruniquel, Jerome; Sardou, Olivier; Trigo, Isabel; Merchant, Chris; Bulgin, Claire; Goettsche, Frank; Olesen, Folke; Prigent, Catherine; Pinnock, Simon

    2014-05-01

    Land surface temperature (LST) is the mean radiative skin temperature of an area of land resulting from the mean balance of solar heating and land-atmosphere cooling fluxes. It is a basic determinant of the terrestrial thermal behaviour, as it controls the effective radiating temperature of the Earth's surface. The sensitivity of LST to soil moisture and vegetation cover means it is an important component in numerous applications. For instance, LST is a key boundary condition in land surface models, which determine the surface to atmosphere fluxes of heat, water and carbon; thus influencing cloud cover, precipitation and atmospheric chemistry predictions within General Circulation Models. Changes in land-surface cover can affect global climate, and also can be identified by changes in their surface temperatures. With the demand of LST data from Earth Observation currently experiencing considerable growth it is important that the users of this data are appropriately engaged by the LST community. The GlobTemperature project under the Data User Element of ESA's 4th Earth Observation Envelope Programme (2013-2017) aims to promote the wider uptake of global-scale satellite LST by the research and operational user communities. As such, the programme of work is focussed on achieving some innovative milestones for LST data which include: detailed global merged geostationary (GEO) and low earth orbit (LEO) data sets with estimates of both clear-sky and under-cloud LST; a first Climate Data Record for LST for the ATSR series of instruments; and the provision of a globally representative and consistent in-situ validation and intercomparison matchup database. Furthermore, the strength of such a venture lies in the coherence and openness of the interactions with the LST and user communities. For instance: detailed user input into the specifications and subsequent testing of the LST data sets; sustained access to data in a user-friendly manner through common data formats; and

  8. Electrolyte solutions including a phosphoranimine compound, and energy storage devices including same

    Science.gov (United States)

    Klaehn, John R.; Dufek, Eric J.; Rollins, Harry W.; Harrup, Mason K.; Gering, Kevin L.

    2017-09-12

    An electrolyte solution comprising at least one phosphoranimine compound and a metal salt. The at least one phosphoranimine compound comprises a compound of the chemical structure ##STR00001## where X is an organosilyl group or a tert-butyl group and each of R.sup.1, R.sup.2, and R.sup.3 is independently selected from the group consisting of an alkyl group, an aryl group, an alkoxy group, or an aryloxy group. An energy storage device including the electrolyte solution is also disclosed.

  9. Beyond the classic thermoneutral zone: Including thermal comfort.

    Science.gov (United States)

    Kingma, Boris Rm; Frijns, Arjan Jh; Schellen, Lisje; van Marken Lichtenbelt, Wouter D

    2014-01-01

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

  10. Vol. 5: Low Temperature Physics

    International Nuclear Information System (INIS)

    Sitenko, A.

    1993-01-01

    Problems of modern physics and the situation with physical research in Ukraine are considered. Programme of the conference includes scientific and general problems. Its proceeding are published in 6 volumes. The papers presented in this volume refer to low-temperature physics

  11. Chemistry of high temperature superconductors

    CERN Document Server

    1991-01-01

    This review volume contains the most up-to-date articles on the chemical aspects of high temperature oxide superconductors. These articles are written by some of the leading scientists in the field and includes a comprehensive list of references. This is an essential volume for researchers working in the fields of ceramics, materials science and chemistry.

  12. Hadrons at finite temperature

    CERN Document Server

    Mallik, Samirnath

    2016-01-01

    High energy laboratories are performing experiments in heavy ion collisions to explore the structure of matter at high temperature and density. This elementary book explains the basic ideas involved in the theoretical analysis of these experimental data. It first develops two topics needed for this purpose, namely hadron interactions and thermal field theory. Chiral perturbation theory is developed to describe hadron interactions and thermal field theory is formulated in the real-time method. In particular, spectral form of thermal propagators is derived for fields of arbitrary spin and used to calculate loop integrals. These developments are then applied to find quark condensate and hadron parameters in medium, including dilepton production. Finally, the non-equilibrium method of statistical field theory to calculate transport coefficients is reviewed. With technical details explained in the text and appendices, this book should be accessible to researchers as well as graduate students interested in thermal ...

  13. High temperature alloys and ceramic heat exchanger

    International Nuclear Information System (INIS)

    Okamoto, Masaharu

    1984-04-01

    From the standpoint of energy saving, the future operating temperatures of process heat and gas turbine plants will become higher. For this purpose, ceramics is the most promissing candidate material in strength for application to high-temperature heat exchangers. This report deals with a servey of characteristics of several high-temperature metallic materials and ceramics as temperature-resistant materials; including a servey of the state-of-the-art of ceramic heat exchanger technologies developed outside of Japan, and a study of their application to the intermediate heat exchanger of VHTR (a very-high-temperature gas-cooled reactor). (author)

  14. High temperature vapors science and technology

    CERN Document Server

    Hastie, John

    2012-01-01

    High Temperature Vapors: Science and Technology focuses on the relationship of the basic science of high-temperature vapors to some areas of discernible practical importance in modern science and technology. The major high-temperature problem areas selected for discussion include chemical vapor transport and deposition; the vapor phase aspects of corrosion, combustion, and energy systems; and extraterrestrial high-temperature species. This book is comprised of seven chapters and begins with an introduction to the nature of the high-temperature vapor state, the scope and literature of high-temp

  15. AgMIP wheat pilot data 4 release

    OpenAIRE

    Asseng, S.; Ewert, F.; Martre, P.; Supit, I.; Wolf, J.

    2015-01-01

    The data set includes a current representative management treatment from detailed, quality-tested sentinel field experiments with wheat from four contrasting environments including Australia, The Netherlands, India and Argentina. Measurements include local daily climate data (solar radiation, maximum and minimum temperature, precipitation, surface wind, dew point temperature, relative humidity, and vapor pressure), soil characteristics, frequent growth, nitrogen in crop and soil, crop and soi...

  16. Temperature indicating device

    International Nuclear Information System (INIS)

    Angus, J.P.; Salt, D.

    1988-01-01

    A temperature indicating device comprises a plurality of planar elements some undergoing a reversible change in appearance at a given temperature the remainder undergoing an irreversible change in appearance at a given temperature. The device is useful in indicating the temperature which an object has achieved as well as its actual temperature. The reversible change is produced by liquid crystal devices. The irreversible change is produced by an absorbent surface carrying substances e.g. waxes which melt at predetermined temperatures and are absorbed by the surface; alternatively paints may be used. The device is used for monitoring processes of encapsulation of radio active waste. (author)

  17. Extending Primitive Spatial Data Models to Include Semantics

    Science.gov (United States)

    Reitsma, F.; Batcheller, J.

    2009-04-01

    Our traditional geospatial data model involves associating some measurable quality, such as temperature, or observable feature, such as a tree, with a point or region in space and time. When capturing data we implicitly subscribe to some kind of conceptualisation. If we can make this explicit in an ontology and associate it with the captured data, we can leverage formal semantics to reason with the concepts represented in our spatial data sets. To do so, we extend our fundamental representation of geospatial data in a data model by including a URI in our basic data model that links it to our ontology defining our conceptualisation, We thus extend Goodchild et al's geo-atom [1] with the addition of a URI: (x, Z, z(x), URI) . This provides us with pixel or feature level knowledge and the ability to create layers of data from a set of pixels or features that might be drawn from a database based on their semantics. Using open source tools, we present a prototype that involves simple reasoning as a proof of concept. References [1] M.F. Goodchild, M. Yuan, and T.J. Cova. Towards a general theory of geographic representation in gis. International Journal of Geographical Information Science, 21(3):239-260, 2007.

  18. Tests of a High Temperature Sample Conditioner for the Waste Treatment Plant LV-S2, LV-S3, HV-S3A and HV-S3B Exhaust Systems

    Energy Technology Data Exchange (ETDEWEB)

    Flaherty, Julia E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Glissmeyer, John A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-18

    Tests were performed to evaluate a sample conditioning unit for stack monitoring at Hanford Tank Waste Treatment and Immobilization Plant (WTP) exhaust stacks with elevated air temperatures. The LV-S2, LV-S3, HV-S3A and HV-S3B exhaust stacks are expected to have elevated air temperature and dew point. At these emission points, exhaust temperatures are too high to deliver the air sample directly to the required stack monitoring equipment. As a result, a sample conditioning system is considered to cool and dry the air prior to its delivery to the stack monitoring system. The method proposed for the sample conditioning is a dilution system that will introduce cooler, dry air to the air sample stream. This method of sample conditioning is meant to reduce the sample temperature while avoiding condensation of moisture in the sample stream. An additional constraint is that the ANSI/HPS N13.1-1999 standard states that at least 50% of the 10 μm aerodynamic diameter (AD) particles present in the stack free stream must be delivered to the sample collector. In other words, depositional loss of particles should be limited to 50% in the sampling, transport, and conditioning systems. Based on estimates of particle penetration through the LV-S3 sampling system, the diluter should perform with about 80% penetration or better to ensure that the total sampling system passes the 50% or greater penetration criterion.

  19. Temperature fluctuations superimposed on background temperature change

    International Nuclear Information System (INIS)

    Otto, James; Roberts, J.A.

    2016-01-01

    Proxy data allows the temperature of the Earth to be mapped over long periods of time. In this work the temperature fluctuations for over 200 proxy data sets were examined and from this set 50 sets were analyzed to test for periodic and quasi-periodic fluctuations in the data sets. Temperature reconstructions over 4 different time scales were analyzed to see if patterns emerged. Data were put into four time intervals; 4,000 years, 14,000 years, 1,000,000 years, and 3,000,000 years and analyzed with a goal to understanding periodic and quasi-periodic patterns in global temperature change superimposed on a “background” average temperature change. Quasi-periodic signatures were identified that predate the Industrial Revolution, during much of which direct data on temperature are not available. These data indicate that Earth temperatures have undergone a number of periodic and quasi-periodic intervals that contain both global warming and global cooling cycles. The fluctuations are superimposed on a background of temperature change that has a declining slope during the two periods, pre-ice age and post ice age with a transition about 12,000 BCE. The data are divided into “events” that span the time periods 3,000,000 BCE to “0” CE, 1,000,000 BCE to “0” CE, 12,000 BCE to 2,000 CE and 2,000 BCE to 2,000 CE. An equation using a quasi-periodic (frequency modulated sine waves) patterns was developed to analyze the date sets for quasi-periodic patterns. “Periodicities” which show reasonable agreement with the predictions of Milankovitch and other investigators were found in the data sets.

  20. Maine River Temperature Monitoring

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We collect seasonal and annual temperature measurements on an hourly or quarter hourly basis to monitor habitat suitability for ATS and other species. Temperature...

  1. GISS Surface Temperature Analysis

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The GISTEMP dataset is a global 2x2 gridded temperature anomaly dataset. Temperature data is updated around the middle of every month using current data files from...

  2. Supersymmetry at high temperatures

    International Nuclear Information System (INIS)

    Das, A.; Kaku, M.

    1978-01-01

    We investigate the properties of Green's functions in a spontaneously broken supersymmetric model at high temperatures. We show that, even at high temperatures, we do not get restoration of supersymmetry, at least in the one-loop approximation

  3. Supersymmetry at finite temperature

    International Nuclear Information System (INIS)

    Clark, T.E.; Love, S.T.

    1983-01-01

    Finite-temperature supersymmetry (SUSY) is characterized by unbroken Ward identities for SUSY variations of ensemble averages of Klein-operator inserted imaginary time-ordered products of fields. Path-integral representations of these products are defined and the Feynman rules in superspace are given. The finite-temperature no-renormalization theorem is derived. Spontaneously broken SUSY at zero temperature is shown not to be restored at high temperature. (orig.)

  4. Room temperature superconductors

    International Nuclear Information System (INIS)

    Sleight, A.W.

    1995-01-01

    If the Holy Grail of room temperature superconductivity could be achieved, the impact on could be enormous. However, a useful room temperature superconductor for most applications must possess a T c somewhat above room temperature and must be capable of sustaining superconductivity in the presence of magnetic fields while carrying a significant current load. The authors will return to the subject of just what characteristics one might seek for a compound to be a room temperature superconductor. 30 refs., 3 figs., 1 tab

  5. High-temperature metallography setup

    International Nuclear Information System (INIS)

    Blumenfeld, M.; Shmarjahu, D.; Elfassy, S.

    1979-06-01

    A high-temperature metallography setup is presented. In this setup the observation of processes such as that of copper recrystallization was made possible, and the structure of metals such as uranium could be revealed. A brief historical review of part of the research works that have been done with the help of high temperature metallographical observation technique since the beginning of this century is included. Detailed description of metallographical specimen preparation technique and theoretical criteria based on the rate of evaporation of materials present on the polished surface of the specimens are given

  6. Digital temperature meter

    Energy Technology Data Exchange (ETDEWEB)

    Glowacki, S

    1982-01-01

    Digital temperature meter for precise temperature measurements is presented. Its parts such as thermostat, voltage-frequency converter and digital frequency meter are described. Its technical parameters such as temperature range 50degC-700degC, measurement precision 1degC, measurement error +-1degC are given. (A.S.).

  7. Rescaling Temperature and Entropy

    Science.gov (United States)

    Olmsted, John, III

    2010-01-01

    Temperature and entropy traditionally are expressed in units of kelvin and joule/kelvin. These units obscure some important aspects of the natures of these thermodynamic quantities. Defining a rescaled temperature using the Boltzmann constant, T' = k[subscript B]T, expresses temperature in energy units, thereby emphasizing the close relationship…

  8. High-temperature superconductivity

    International Nuclear Information System (INIS)

    Lynn, J.W.

    1990-01-01

    This book discusses development in oxide materials with high superconducting transition temperature. Systems with Tc well above liquid nitrogen temperature are already a reality and higher Tc's are anticipated. The author discusses how the idea of a room-temperature superconductor appears to be a distinctly possible outcome of materials research

  9. Nonlinear waves in electron–positron–ion plasmas including charge ...

    Indian Academy of Sciences (India)

    The effects of the driving electric field, ion temperature, positron density, ion drift, Mach number and propagation angle are investigated. It is shown that depending on the driving electric field, ion temperature, positron density, ion drift, Mach number and propagation angle, the numerical solutions exhibit waveforms that are ...

  10. Nuclear fuels for very high temperature applications

    International Nuclear Information System (INIS)

    Lundberg, L.B.; Hobbins, R.R.

    1992-01-01

    The success of the development of nuclear thermal propulsion devices and thermionic space nuclear power generation systems depends on the successful utilization of nuclear fuel materials at temperatures in the range 2000 to 3500 K. Problems associated with the utilization of uranium bearing fuel materials at these very high temperatures while maintaining them in the solid state for the required operating times are addressed. The critical issues addressed include evaporation, melting, reactor neutron spectrum, high temperature chemical stability, fabrication, fission induced swelling, fission product release, high temperature creep, thermal shock resistance, and fuel density, both mass and fissile atom. Candidate fuel materials for this temperature range are based on UO 2 or uranium carbides. Evaporation suppression, such as a sealed cladding, is required for either fuel base. Nuclear performance data needed for design are sparse for all candidate fuel forms in this temperature range, especially at the higher temperatures

  11. Brain temperature and exercise performance

    DEFF Research Database (Denmark)

    Nybo, Lars

    2012-01-01

    Events arising within the central nervous system seem to play a major factor in the aetiology of hyperthermia-induced fatigue. Thus, various studies with superimposed electrical nerve stimulation or transcranial magnetic stimulation have shown that both passive and exercise-induced hyperthermia...... temperature in exercising goats indicate that excessive brain hyperthermia will directly affect motor performance. However, several homeostatic changes arise in parallel with hyperthermia including factors that may influence both peripheral and central fatigue and it is likely that these changes interact...... will impair voluntary motor activation during sustained maximal contractions. In humans the brain temperature increases in parallel with that of the body core making it very difficult to evaluate the independent effect of the cerebral temperature. Experiments with separate manipulation of the brain...

  12. Viscoelastic creep of high-temperature concrete

    International Nuclear Information System (INIS)

    Pfeiffer, P.A.; Marchertas, A.H.; Bazant, Z.P.

    1985-01-01

    Presented in this report is the analytical model for analysis of high temperature creep response of concrete. The creep law used is linear (viscoelastic), the temperature and moisture effects on the creep rate and also aging are included. Both constant and transient temperature as well as constant and transient moisture conditions are considered. Examples are presented to correlate experimental data with parameters of the analytical model by the use of a finite element scheme

  13. Temperature compensated photovoltaic array

    Science.gov (United States)

    Mosher, Dan Michael

    1997-11-18

    A temperature compensated photovoltaic module (20) comprised of a series of solar cells (22) having a thermally activated switch (24) connected in parallel with several of the cells (22). The photovoltaic module (20) is adapted to charge conventional batteries having a temperature coefficient (TC) differing from the temperature coefficient (TC) of the module (20). The calibration temperatures of the switches (24) are chosen whereby the colder the ambient temperature for the module (20), the more switches that are on and form a closed circuit to short the associated solar cells (22). By shorting some of the solar cells (22) as the ambient temperature decreases, the battery being charged by the module (20) is not excessively overcharged at lower temperatures. PV module (20) is an integrated solution that is reliable and inexpensive.

  14. Locality of Temperature

    Science.gov (United States)

    Kliesch, M.; Gogolin, C.; Kastoryano, M. J.; Riera, A.; Eisert, J.

    2014-07-01

    This work is concerned with thermal quantum states of Hamiltonians on spin- and fermionic-lattice systems with short-range interactions. We provide results leading to a local definition of temperature, thereby extending the notion of "intensivity of temperature" to interacting quantum models. More precisely, we derive a perturbation formula for thermal states. The influence of the perturbation is exactly given in terms of a generalized covariance. For this covariance, we prove exponential clustering of correlations above a universal critical temperature that upper bounds physical critical temperatures such as the Curie temperature. As a corollary, we obtain that above the critical temperature, thermal states are stable against distant Hamiltonian perturbations. Moreover, our results imply that above the critical temperature, local expectation values can be approximated efficiently in the error and the system size.

  15. Biophysical control of leaf temperature

    Science.gov (United States)

    Dong, N.; Prentice, I. C.; Wright, I. J.

    2014-12-01

    and air temperature is generally neglected in terrestrial ecosystem and carbon cycle models. This is a significant omission that could lead to an over-estimation of the heat-stress vulnerability of carbon uptake in the wet tropics. Leaf energy balance theory is well established, and should be included in the next generation of models.

  16. Extreme Maximum Land Surface Temperatures.

    Science.gov (United States)

    Garratt, J. R.

    1992-09-01

    There are numerous reports in the literature of observations of land surface temperatures. Some of these, almost all made in situ, reveal maximum values in the 50°-70°C range, with a few, made in desert regions, near 80°C. Consideration of a simplified form of the surface energy balance equation, utilizing likely upper values of absorbed shortwave flux (1000 W m2) and screen air temperature (55°C), that surface temperatures in the vicinity of 90°-100°C may occur for dry, darkish soils of low thermal conductivity (0.1-0.2 W m1 K1). Numerical simulations confirm this and suggest that temperature gradients in the first few centimeters of soil may reach 0.5°-1°C mm1 under these extreme conditions. The study bears upon the intrinsic interest of identifying extreme maximum temperatures and yields interesting information regarding the comfort zone of animals (including man).

  17. Zirconium-based alloys, nuclear fuel rods and nuclear reactors including such alloys, and related methods

    Science.gov (United States)

    Mariani, Robert Dominick

    2014-09-09

    Zirconium-based metal alloy compositions comprise zirconium, a first additive in which the permeability of hydrogen decreases with increasing temperatures at least over a temperature range extending from 350.degree. C. to 750.degree. C., and a second additive having a solubility in zirconium over the temperature range extending from 350.degree. C. to 750.degree. C. At least one of a solubility of the first additive in the second additive over the temperature range extending from 350.degree. C. to 750.degree. C. and a solubility of the second additive in the first additive over the temperature range extending from 350.degree. C. to 750.degree. C. is higher than the solubility of the second additive in zirconium over the temperature range extending from 350.degree. C. to 750.degree. C. Nuclear fuel rods include a cladding material comprising such metal alloy compositions, and nuclear reactors include such fuel rods. Methods are used to fabricate such zirconium-based metal alloy compositions.

  18. Hydromechanical modeling of clay rock including fracture damage

    Science.gov (United States)

    Asahina, D.; Houseworth, J. E.; Birkholzer, J. T.

    2012-12-01

    Argillaceous rock typically acts as a flow barrier, but under certain conditions significant and potentially conductive fractures may be present. Fracture formation is well-known to occur in the vicinity of underground excavations in a region known as the excavation disturbed zone. Such problems are of particular importance for low-permeability, mechanically weak rock such as clays and shales because fractures can be relatively transient as a result of fracture self-sealing processes. Perhaps not as well appreciated is the fact that natural fractures can form in argillaceous rock as a result of hydraulic overpressure caused by phenomena such as disequlibrium compaction, changes in tectonic stress, and mineral dehydration. Overpressure conditions can cause hydraulic fracturing if the fluid pressure leads to tensile effective stresses that exceed the tensile strength of the material. Quantitative modeling of this type of process requires coupling between hydrogeologic processes and geomechanical processes including fracture initiation and propagation. Here we present a computational method for three-dimensional, hydromechanical coupled processes including fracture damage. Fractures are represented as discrete features in a fracture network that interact with a porous rock matrix. Fracture configurations are mapped onto an unstructured, three-dimensonal, Voronoi grid, which is based on a random set of spatial points. Discrete fracture networks (DFN) are represented by the connections of the edges of a Voronoi cells. This methodology has the advantage that fractures can be more easily introduced in response to coupled hydro-mechanical processes and generally eliminates several potential issues associated with the geometry of DFN and numerical gridding. A geomechanical and fracture-damage model is developed here using the Rigid-Body-Spring-Network (RBSN) numerical method. The hydrogelogic and geomechanical models share the same geometrical information from a 3D Voronoi

  19. Melting temperature of graphite

    International Nuclear Information System (INIS)

    Korobenko, V.N.; Savvatimskiy, A.I.

    2001-01-01

    Full Text: Pulse of electrical current is used for fast heating (∼ 1 μs) of metal and graphite specimens placed in dielectric solid media. Specimen consists of two strips (90 μm in thick) placed together with small gap so they form a black body model. Quasy-monocrystal graphite specimens were used for uniform heating of graphite. Temperature measurements were fulfilled with fast pyrometer and with composite 2-strip black body model up to melting temperature. There were fulfilled experiments with zirconium and tungsten of the same black body construction. Additional temperature measurements of liquid zirconium and liquid tungsten are made. Specific heat capacity (c P ) of liquid zirconium and of liquid tungsten has a common feature in c P diminishing just after melting. It reveals c P diminishing after melting in both cases over the narrow temperature range up to usual values known from steady state measurements. Over the next wide temperature range heat capacity for W (up to 5000 K) and Zr (up to 4100 K) show different dependencies of heat capacity on temperature in liquid state. The experiments confirmed a high quality of 2-strip black body model used for graphite temperature measurements. Melting temperature plateau of tungsten (3690 K) was used for pyrometer calibration area for graphite temperature measurement. As a result, a preliminary value of graphite melting temperature of 4800 K was obtained. (author)

  20. Operational Linescan System (OLS) - Derived Products (including posters and slides)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Visible and infrared imagery from DMSP Operational Linescan System (OLS) instruments are used to monitor the global distribution of clouds and cloud top temperatures...