WorldWideScience

Sample records for metal temperature monitoring

  1. Metal temperature monitoring in corrosive gases at high temperature and high thermal flows; Monitoreo de temperaturas de metal en gases corrosivos a alta temperatura y altos flujos termicos

    Energy Technology Data Exchange (ETDEWEB)

    Huerta Espino, Mario; Martinez Flores, Marco Antonio; Martinez Villafane, Alberto; Porcayo Calderon, Jesus; Gomez Guzman, Roberto; Reyes Cervantes, Fernando [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1990-12-31

    The direct measurement of metal temperatures during operation in superheater, reheater, and water wall tubes in zones exposed to high thermal flows is of great interest for the operation and analysis of the correct functioning of a steam generator. The operation temperature measurement of these zones differs very much of the monitored temperature in headers in the dead chamber, since the temperature measured in this zone is the steam temperature that does not reflect the one detected in the gas zone. For this reason, the thermocouples implant in gas zones will detect the real metal temperature and the incidence that some operation variables might have on it (Martinez et al., (1990). [Espanol] La medicion directa de temperaturas de metal durante operacion en tubos de sobrecalentador, recalentador y pared de agua en zonas expuestas a altos flujos termicos es de gran interes para la operacion y analisis del buen funcionamiento de un generador de vapor. La medicion de la temperatura de operacion de estas zonas, difiere mucho de la temperatura monitoreada en cabezales en zona de camara muerta, ya que la temperatura registrada en esta zona es la de vapor que no es un reflejo de la detectada en zona de gases. Por esta razon, la implantacion de termopares en zona de gases detectara la temperatura de metal real y la incidencia que algunas variables de operacion tengan sobre esta (Martinez et al., 1990).

  2. Rapid response sensor to monitor the temperature and flow of liquid metals

    International Nuclear Information System (INIS)

    McCann, J.D.

    1980-01-01

    Two forms of a sensor capable of simultaneously monitoring the temperature and flow of liquid metal coolants within a reactor are described. They operate by measuring the coupling impedances between the sensor and the surrounding electrically conductive coolant. Since the system utilises electrical rather than thermal properties, the response to perturbations is rapid, typically displaying the changed conditions within a few milliseconds. The first form of the sensor was designed to operate whilst protected by a thick walled service tube positioned in the reactor coolant. Providing bends in the tube had a radius greater than 70 cm, the sensor could be removed for inspection and maintenance if necessary. The second sensor was fitted inside a streamlined NaK proof capsule. This was inserted directly into the coolant outlet stream of a fuel pin assembly in the Dounreay Fast Reactor. In this form the sensor successfully monitored flow, entrained gas and temperature excursions during the final operating cycle of D.F.R. (author)

  3. Monitoring of bolt clamping force at high temperatures using metal-packaged regenerated fiber Bragg grating strain sensors

    Science.gov (United States)

    Huang, Yong-Kuo; Tu, Yun; Tu, Shan-Tung

    2017-10-01

    Insufficient or excessive preload has been regarded as the main issue that may endanger the safety of bolted joints operated at high temperatures. A new technique for monitoring the bolt clamping force is thus proposed using metal-packaged regenerated fiber Bragg grating (RFBG) strain sensors spot-welded onto the bolt. The measurement of the clamping force in a bolted steel-steel joint subjected to thermal loading is conducted. The experimental results show that the bolt clamping force can be monitored by the metal-packaged RFBG strain sensor at high temperatures up to 500 °C. This technique provides a new possibility for structural health monitoring of bolted joints operated at high temperatures.

  4. Flexible metallic ultrasonic transducers for structural health monitoring of pipes at high temperatures.

    Science.gov (United States)

    Shih, Jeanne-Louise; Kobayashi, Makiko; Jen, Cheng-Kuei

    2010-09-01

    Piezoelectric films have been deposited by a sol-gel spray technique onto 75-μm-thick titanium and stainless steel (SS) membranes and have been fabricated into flexible ultrasonic transducers (FUTs). FUTs using titanium membranes were glued and those using SS membranes brazed onto steel pipes, procedures that serve as on-site installation techniques for the purpose of offering continuous thickness monitoring capabilities at up to 490 °C. At 150 °C, the thickness measurement accuracy of a pipe with an outer diameter of 26.6 mm and a wall thickness of 2.5 mm was estimated to be 26 μm and the center frequency of the FUT was 10.8 MHz. It is demonstrated that the frequency bandwidth of the FUTs and SNR of signals using glue or brazing materials as high-temperature couplant for FUTs are sufficient to inspect the steel pipes even with a 2.5 mm wall thickness.

  5. 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...

  6. Fabrication and characterization of a metal-packaged regenerated fiber Bragg grating strain sensor for structural integrity monitoring of high-temperature components

    International Nuclear Information System (INIS)

    Tu, Yun; Tu, Shan-Tung

    2014-01-01

    Assessment of the structural integrity of components operating at high temperatures requires the development of novel sensors to measure strain. A metal-packaged regenerated fiber Bragg grating (RFBG) sensor is developed for measurement of strain using titanium–silver magnetron sputtering and nickel electroplating. The strain response of the sensor mounted onto a flat tensile specimen by spot welding is evaluated by uniaxial tensile tests at constant temperatures ranging from room temperature to 400 °C. Similar tests are performed on a bare RFBG sensor for comparison. The metal-packaged RFBG strain sensor exhibits higher strain sensitivity than that of the bare RFBG sensor, as well as good linearity, stability and repeatability of strain measurements. A three-dimensional finite element model of the sensor is established to predict the strain sensitivity based on the sensing principle of the fiber Bragg grating. Comparisons of the experimental results with the numerical predictions for the strain sensitivity show a satisfactory agreement. These results demonstrate that the metal-packaged RFBG strain sensors can be successfully fabricated by combining magnetron sputtering with electroplating, and provide great promise for structural integrity monitoring of high-temperature components. (paper)

  7. High temperature metallic recuperator

    Science.gov (United States)

    Ward, M. E.; Solmon, N. G.; Smeltzer, C. E.

    1981-06-01

    An industrial 4.5 MM Btu/hr axial counterflow recuperator, fabricated to deliver 1600 F combustion air, was designed to handle rapid cyclic loading, a long life, acceptable costs, and a low maintenance requirement. A cost benefit anlysis of a high temperature waste heat recovery system utilizing the recurperator and components capable of 1600 F combustion air preheat shows that this system would have a payback period of less than two years. Fifteen companies and industrial associations were interviewed and expressed great interest in recuperation in large energy consuming industries. Determination of long term environmental effects on candidate recuperator tubing alloys was completed. Alloys found to be acceptable in the 2200 F flue gas environment of a steel billet reheat furnace, were identified.

  8. Passive electronic identification with temperature monitoring. [Temperature monitor for cattle

    Energy Technology Data Exchange (ETDEWEB)

    Holm, D.M.; Bobbett, R.E.; Koelle, A.R.; Landt, J.A.; Sanders, W.M.; Depp, S.W.; Seawright, G.L.

    1976-01-01

    The United States Department of Agriculture (USDA) and the Energy Research and Development Administration (ERDA) have been supporting an electronic identification and temperature monitoring project at the Los Alamos Scientific Laboratory (LASL) since early 1973. The development, so far, indicates that a subdermally-implanted, electronic transponder (having no batteries) can be remotely activated and transmit temperature and identification information back to a receiver in a few tenths of a second. If this electronic identification and temperature monitoring system is developed into a commercially available product line, and is widely accepted by the cattle industry, it will enable them to carry out more extensive management practices. Better management can result in greater efficiency and productivity. The system will also enable regulatory agencies to trace the movements of diseased animals through commerce, and thus assist in disease control measures. Work so far has been concentrated primarily on determining the technical feasibility of the electronic concepts. (auth)

  9. High temperature corrosion of metals

    International Nuclear Information System (INIS)

    Quadakkers, W.J.; Schuster, H.; Ennis, P.J.

    1988-08-01

    This paper covers three main topics: 1. high temperature oxidation of metals and alloys, 2. corrosion in sulfur containing environments and 3. structural changes caused by corrosion. The following 21 subjects are discussed: Influence of implanted yttrium and lanthanum on the oxidation behaviour of beta-NiA1; influence of reactive elements on the adherence and protective properties of alumina scales; problems related to the application of very fine markers in studying the mechanism of thin scale formation; oxidation behaviour of chromia forming Co-Cr-Al alloys with or without reactive element additions; growth and properties of chromia-scales on high-temperature alloys; quantification of the depletion zone in high temperature alloys after oxidation in process gas; effects of HC1 and of N2 in the oxidation of Fe-20Cr; investigation under nuclear safety aspects of Zircaloy-4 oxidation kinetics at high temperatures in air; on the sulfide corrosion of metallic materials; high temperature sulfide corrosion of Mn, Nb and Nb-Si alloys; corrosion behaviour or NiCrAl-based alloys in air and air-SO2 gas mixtures; sulfidation of cobalt at high temperatures; preoxidation for sulfidation protection; fireside corrosion and application of additives in electric utility boilers; transport properties of scales with complex defect structures; observations of whiskers and pyramids during high temperature corrosion of iron in SO2; corrosion and creep of alloy 800H under simulated coal gasification conditions; microstructural changes of HK 40 cast alloy caused by exploitation in tubes in steam reformer installation; microstructural changes during exposure in corrosive environments and their effect on mechanical properties; coatings against carburization; mathematical modeling of carbon diffusion and carbide precipitation in Ni-Cr-based alloys. (MM)

  10. Energy Doubler cryoloop temperature monitor system

    International Nuclear Information System (INIS)

    Pucci, G.; Howard, D.

    1981-10-01

    The Cryoloop Temperature Monitor System is a fully electronic system designed to monitor temperature at key points in the Energy Doubler cryoloop system. It is used for cryoloop diagnostics, temperature studies, and cooldown valve control

  11. High temperature ceramic/metal joint structure

    Science.gov (United States)

    Boyd, Gary L. (Inventor)

    1991-01-01

    A high temperature turbine engine includes a hybrid ceramic/metallic rotor member having ceramic/metal joint structure. The disclosed joint is able to endure higher temperatures than previously possible, and aids in controlling heat transfer in the rotor member.

  12. Monitoring eucalypt bud temperature using mobile temperature ...

    African Journals Online (AJOL)

    Utilisation of traditional methods of air and bud temperature measurement were not viable, due to significant risks of data and meteorological equipment loss posed by severe weather, vandalism and theft. Between 1996 and 2004, a robust structure for housing the miniature Hobo® temperature logger (hereafter termed ...

  13. PC-based temperature monitoring

    International Nuclear Information System (INIS)

    Sayne Lei Shwe; Pho Kaung; Zaw Win; Myint Kyi

    2001-01-01

    An economical and practical thermometer interface for the IBM compatible personal computer (PC) has been developed. It can indicate temperature changes as little as 0.4 0 C and covers a temperature range of zero to 100 0 C. Those involved in scientific studies can use it not only as a temperature recorde/display but also as a temperature controller. (author)

  14. Determination of irradiation temperature using SiC temperature monitors

    International Nuclear Information System (INIS)

    Maruyama, Tadashi; Onose, Shoji

    1999-01-01

    This paper describes a method for detecting the change in length of SiC temperature monitors and a discussion is made on the relationship between irradiation temperature and the recovery in length of SiC temperature monitors. The SiC specimens were irradiated in the experimental fast reactor JOYO' at the irradiation temperatures around 417 to 645degC (design temperature). The change in length of irradiated specimens was detected using a dilatometer with SiO 2 glass push rod in an infrared image furnace. The temperature at which recovery in macroscopic length begins was obtained from the annealing intersection temperature. The results of measurements indicated that a difference between annealing intersection temperature and the design temperature sometimes reached well over ±100degC. A calibration method to obtain accurate irradiation temperature was presented and compared with the design temperature. (author)

  15. The 'Nuts and Bolts' of 13C NMR Spectroscopy at Elevated-Pressures and -Temperatures for Monitoring In Situ CO2 Conversion to Metal Carbonates

    Science.gov (United States)

    Moore, J. K.; Surface, J. A.; Skemer, P. A.; Conradi, M. S.; Hayes, S. E.

    2013-12-01

    We will present details of newly-constructed specialized NMR designed to conduct in situ elevated-pressure, elevated-temperature 13C NMR studies on unmixed slurries of minerals in the presence of CO2 or other gases. This static probe is capable of achieving 300 bar, 300C conditions, and it is designed to spectroscopically examine 13C signals in mixtures of solids, liquids, gases, and supercritical fluids. Ultimately, our aim is to monitor CO2 uptake in both ultramafic rocks and in more porous geological materials to understand the mechanisms of chemisorption as a function of temperature, pressure and pH. We will give details of the hardware setup, and we will show a variety of static in situ NMR, as well as ex situ 'magic-angle spinning' NMR to show the analyses that are possible of minerals in pure form and in mixtures. In addition, specific NMR pulse sequences, techniques, and modeling will be described in detail. In this in situ NMR probe, we are able to simulate processes at geologically relevant fluid pressures and temperatures, monitoring the kinetics of CO2 conversion to carbonates. The in situ NMR experiments consist of heterogeneous mixtures of rock, salty brine solution, and moderate pressure CO2 gas at elevated temperatures. The purpose of studying these reactions is to determine conditions that affect the efficacy of carbonate formation in various targeted geological reservoirs (i.e., peroditite, or others). Via 13C NMR, we have spectroscopically characterized and quantified the conversion of CO2 to magnesium carbonate and calcium carbonate minerals, including metastable intermediates (such as hydromagnesite, or dypingite in the case of magnesium carbonate species, or vaterite in the case of calcium carbonate species). Such species are distinguishable from a combination of the 13C isotropic chemical shift, the static 13C lineshape, and changes in spin-lattice (T1) relaxation times. We will demonstrate that NMR can be used for quantitative

  16. High-temperature superconductivity of granulated metals

    CERN Document Server

    Mejlikhov, E Z

    2001-01-01

    Only the area of relatively low temperatures was traditionally considered in the theoretical ands experimental studies on the nanocomposites (granulated metals) conductivity, related to the intergranular electrons tunneling. The conductivity temperature dependence in this mode is exponential. However, according to the experiment the character of the nanocomposites conductivity at higher temperatures essentially changes. The model, relating the peculiarities of the granulated metals conductivity at high temperatures, to the involvement of the multicharged granules in this process under the conditions of high spread of their sizes, is proposed. The model conclusions are in agreement with the experiment

  17. Temperature Monitoring and Perioperative Thermoregulation

    Science.gov (United States)

    Sessler, Daniel I.

    2008-01-01

    Most clinically available thermometers accurately report the temperature of whatever tissue is being measured. The difficulty is that no reliably core-temperature measuring sites are completely non-invasive and easy to use — especially in patients not having general anesthesia. Nonetheless, temperature can be reliably measured in most patients. Body temperature should be measured in patients having general anesthesia exceeding 30 minutes in duration, and in patients having major operations under neuraxial anesthesia. Core body temperature is normally tightly regulated. All general anesthetics produce a profound dose-dependent reduction in the core temperature triggering cold defenses including arterio-venous shunt vasoconstriction and shivering. Anesthetic-induced impairment of normal thermoregulatory control, and the resulting core-to-peripheral redistribution of body heat, is the primary cause of hypothermia in most patients. Neuraxial anesthesia also impairs thermoregulatory control, although to a lesser extant than general anesthesia. Prolonged epidural analgesia is associated with hyperthermia whose cause remains unknown. PMID:18648241

  18. Low temperature dissolution flowsheet for plutonium metal

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, W. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Almond, P. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Rudisill, T. S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-05-01

    The H-Canyon flowsheet used to dissolve Pu metal for PuO2 production utilizes boiling HNO3. SRNL was requested to develop a complementary dissolution flowsheet at two reduced temperature ranges. The dissolution and H2 generation rates of Pu metal were investigated using a dissolving solution at ambient temperature (20-30 °C) and for an intermediate temperature of 50-60 °C. Additionally, the testing included an investigation of the dissolution rates and characterization of the off-gas generated from the ambient temperature dissolution of carbon steel cans and the nylon bags that contain the Pu metal when charged to the dissolver.

  19. Criteria for core sampling bit temperature monitor

    International Nuclear Information System (INIS)

    Francis, P.M.

    1994-08-01

    A temperature monitoring device needs to be developed for the tank core sampling trucks. It will provide an additional indication of safe drill bit temperatures and give the operator a better feel for the effects of changing drill settings. This document defines the criteria for the bit monitoring system, including performance requirements, information on the core sampling system, and other conditions that may be encountered

  20. Elevated temperature erosive wear of metallic materials

    International Nuclear Information System (INIS)

    Roy, Manish

    2006-01-01

    Solid particle erosion of metals and alloys at elevated temperature is governed by the nature of the interaction between erosion and oxidation, which, in turn, is determined by the thickness, pliability, morphology, adhesion characteristics and toughness of the oxide scale. The main objective of this paper is to critically review the present state of understanding of the elevated temperature erosion behaviour of metals and alloys. First of all, the erosion testing at elevated temperature is reviewed. This is followed by discussion of the essential features of elevated temperature erosion with special emphasis on microscopic observation, giving details of the erosion-oxidation (E-O) interaction mechanisms. The E-O interaction has been elaborated in the subsequent section. The E-O interaction includes E-O maps, analysis of transition criteria from one erosion mechanism to another mechanism and quantification of enhanced oxidation kinetics during erosion. Finally, the relevant areas for future studies are indicated. (topical review)

  1. Remote System of Temperature Monitoring and Control

    Directory of Open Access Journals (Sweden)

    Vítor Carvalho

    2008-11-01

    Full Text Available This paper presents a system capable of monitoring and control remotely the temperature of a physical space. This work was part of a final year graduation of the Industrial Informatics Course at the Polytechnic Institute of Cávado and Ave. It was developed by an undergraduate student using a LabVIEW custom application with a methodology of on-off control. The local user can use a touch screen display to configure the system setpoint temperature and for overall monitoring. For remote access it can be used any device supporting LabVIEW environment.

  2. Metallic Membranes for High Temperature Hydrogen Separation

    DEFF Research Database (Denmark)

    Ma, Y.H.; Catalano, Jacopo; Guazzone, Federico

    2013-01-01

    Composite palladium membranes have extensively been studied in laboratories and, more recently, in small pilot industrial applications for the high temperature separation of hydrogen from reactant mixtures such as water-gas shift (WGS) reaction or methane steam reforming (MSR). Composite Pd...... than 1000, respectively. This chapter describes in detail composite Pd-based membrane preparation methods, which consist of the grading of the support and the deposition of the dense metal layer, their performances, and their applications in catalytic membrane reactors (CMRs) at high temperatures (400...

  3. Monitoring Temperatures of Tires Using Luminescent Materials

    Science.gov (United States)

    Bencic, Timothy J

    2006-01-01

    A method of noncontact, optical monitoring of the surface temperature of a tire has been devised to enable the use of local temperature rise as an indication of potential or impending failures. The method involves the use of temperature-sensitive paint (or filler): Temperature-sensitive luminescent dye molecules or other luminescent particles are incorporated into a thin, flexible material coating the tire surface of interest. (Alternatively, in principle, the luminescent material could be incorporated directly into the tire rubber, though this approach has not yet been tested.) The coated surface is illuminated with shorter-wavelength light to excite longer-wavelength luminescence, which is observed by use of a charge-coupled-device camera or a photodetector (see Figure 1). If temporally constant illumination is used, then the temperature can be deduced from the known temperature dependence of the intensity response of the luminescence. If pulsed illumination is used, then the temperature can be deduced from the known temperature dependence of the time or frequency response of the luminescence. If sinusoidally varying illumination is used, then the temperature can be deduced from the known temperature dependence of the phase response of the luminescence. Unlike a prior method of monitoring the temperature at a fixed spot on a tire by use of a thermocouple, this method is not restricted to one spot and can, therefore, yield information on the spatial distribution of temperature: in particular, it enables the discovery of newly forming hot spots where damage may be starting. Also unlike in the thermocouple method, the measurements in this method are not vulnerable to breakage of wires in repeated flexing of the tire. Moreover, unlike in another method in which infrared radiation is monitored as an indication of surface temperature, the luminescence measurements in this method are not significantly affected by changes in infrared emissivity. This method has been

  4. Strength versus temperature anomalies in metals

    CERN Document Server

    Fisher, D J

    2015-01-01

    Perhaps the best-known aspect of the behavior of metals, and indeed of most materials, is that they weaken with temperature. This weakening is however a problem in some applications. Only tungsten for instance, with its naturally high melting-point, was suitable for the manufacture of the filaments of incandescent light-bulbs. Even then, it was necessary to add oxide particles having a yethigher melting-point in order to prevent the weakening effect of grain-growth. These are alloys however which can be said to be weakened by heat, but nevertheless 'hang on' to enough strength to perform their

  5. 21 CFR 882.5500 - Lesion temperature monitor.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lesion temperature monitor. 882.5500 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5500 Lesion temperature monitor. (a) Identification. A lesion temperature monitor is a device used to monitor the tissue...

  6. Optimizing performance of half-metals at finite temperature

    NARCIS (Netherlands)

    Attema, J. J.; de Wijs, G. A.; de Groot, R. A.

    2007-01-01

    Several aspects of half-metallic magnetism at finite temperature are discussed. Since NiMnSb is the simplest half-metal and the longest known it will be used as an example. Also it is a half-metal with remarkable little on-site Coulomb repulsion. Consequently it is a half-metal that is not notably

  7. Engineering: Liquid metal pumped at a record temperature

    Science.gov (United States)

    Lambrinou, Konstantina

    2017-10-01

    Although liquid metals are effective fluids for heat transfer, pumping them at high temperatures is limited by their corrosiveness to solid metals. A clever pump design addresses this challenge using only ceramics. See Article p.199

  8. High-temperature spreading kinetics of metals

    Energy Technology Data Exchange (ETDEWEB)

    Rauch, N.

    2005-05-15

    In this PhD work a drop transfer setup combined with high speed photography has been used to analyze the spreading of Ag on polished polycrystalline Mo and single crystalline Mo (110) and (100) substrates. The objective of this work was to unveil the basic phenomena controlling spreading in metal-metal systems. The observed spreading kinetics were compared with current theories of low and high temperature spreading such as a molecular kinetic model and a fluid flow model. Analyses of the data reveal that the molecular model does describe the fastest velocity data well for all the investigated systems. Therefore, the energy which is dissipated during the spreading process is a dissipation at the triple line rather than dissipation due to the viscosity in the liquid. A comparison of the determined free activation energy for wetting of {delta}G95{approx}145kJ/mol with literature values allows the statement that the rate determining step seems to be a surface diffusion of the Ag atoms along the triple line. In order to investigate possible ridge formation, due to local atomic diffusion of atoms of the substrate at the triple during the spreading process, grooving experiments of the polycrystalline Mo were performed to calculate the surface diffusities that will control ridge evolution. The analyses of this work showed that a ridge formation at the fastest reported wetting velocities was not possible if there is no initial perturbation for a ridge. If there was an initial perturbation for a ridge the ridge had to be much smaller than 1 nm in order to be able to move with the liquid font. Therefore ridge formation does not influence the spreading kinetics for the studied system and the chosen conditions. SEM, AFM and TEM investigations of the triple line showed that ridge formation does also not occur at the end of the wetting experiment when the drop is close to equilibrium and the wetting velocity is slow. (orig.)

  9. The detection of wind turbine shaft misalignment using temperature monitoring

    OpenAIRE

    Tonks, Oliver; Wang, Qing

    2016-01-01

    Temperature is a parameter increasingly monitored in wind turbine systems. This paper details a potential temperature monitoring technique for use on shaft couplings. Such condition monitoring methods aid fault detection in other areas of wind turbines. However, application to shaft couplings has not previously been widely researched. A novel temperature measurement technique is outlined, using an infra-red thermometer which can be applied to online condition monitoring. The method was va...

  10. Monitoring on internal temperature of composite insulator with embedding fiber Bragg grating for early diagnosis

    Science.gov (United States)

    Chen, Wen; Tang, Ming

    2017-04-01

    The abnormal temperature rise is the precursor of the defective composite insulator in power transmission line. However no consolidated techniques or methodologies can on line monitor its internal temperature now. Thus a new method using embedding fiber Bragg grating (FBG) in fiber reinforced polymer (FRP) rod is adopted to monitor its internal temperature. To correctly demodulate the internal temperature of FRP rod from the Bragg wavelength shift of FBG, the conversion coefficient between them is deduced theoretically based on comprehensive investigation on the thermal stresses of the metal-composite joint, as well as its material and structural properties. Theoretical model shows that the conversion coefficients of FBG embedded in different positions will be different because of non-uniform thermal stress distribution, which is verified by an experiment. This work lays the theoretical foundation of monitoring the internal temperature of composite insulator with embedding FBG, which is of great importance to its health structural monitoring, especially early diagnosis.

  11. Channel Islands, Kelp Forest Monitoring, Sea Temperature, 1993-2007

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset from the Channel Islands National Park's Kelp Forest Monitoring Program has subtidal temperature data taken at permanent monitoring sites. Since 1993,...

  12. Northern Mariana Islands Marine Monitoring Team Sea Temperature Measurements

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Site specific monitoring of sea temperature is conducted using submersible temperature dataloggers at selected sites and depths around the islands of Saipan and Rota.

  13. Metal-semiconductor interface in extreme temperature conditions

    International Nuclear Information System (INIS)

    Bulat, L.P.; Erofeeva, I.A.; Vorobiev, Yu.V.; Gonzalez-Hernandez, J.

    2008-01-01

    We present an investigation of electrons' and phonons' temperatures in the volume of a semiconductor (or metal) sample and at the interface between metal and semiconductor. Two types of mismatch between electrons' and phonons' temperatures take place: at metal-semiconductor interfaces and in the volume of the sample. The temperature mismatch leads to nonlinear terms in expressions for heat and electricity transport. The nonlinear effects should be taken into consideration in the study of electrical and heat transport in composites and in electronic chips

  14. Real-time optoacoustic monitoring of temperature in tissues

    Energy Technology Data Exchange (ETDEWEB)

    Larina, Irina V [Center for Biomedical Engineering, University of Texas Medical Branch, Galveston, TX 77555-0456 (United States); Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555-0456 (United States); Larin, Kirill V [Center for Biomedical Engineering, University of Texas Medical Branch, Galveston, TX 77555-0456 (United States); Esenaliev, Rinat O [Center for Biomedical Engineering, University of Texas Medical Branch, Galveston, TX 77555-0456 (United States); Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555-0456 (United States); Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX 77555-0456 (United States)

    2005-08-07

    To improve the safety and efficacy of thermal therapy, it is necessary to map tissue temperature in real time with submillimetre spatial resolution. Accurate temperature maps may provide the necessary control of the boundaries of the heated regions and minimize thermal damage to surrounding normal tissues. Current imaging modalities fail to monitor tissue temperature in real time with high resolution and accuracy. We investigated a non-invasive optoacoustic method for accurate, real-time monitoring of tissue temperature during thermotherapy. In this study, we induced temperature gradients in tissue and tissue-like samples and monitored the temperature distribution using the optoacoustic technique. The fundamental harmonic of a Q-switched Nd : YAG laser ({lambda} = 1064 nm) was used for optoacoustic wave generation and probing of tissue temperature. The tissue temperature was also monitored with a multi-sensor temperature probe inserted in the samples. Good agreement between optoacoustically measured and actual tissue temperatures was obtained. The accuracy of temperature monitoring was better than 1{sup 0}C, while the spatial resolution was about 1 mm. These data suggest that the optoacoustic technique has the potential to be used for non-invasive, real-time temperature monitoring during thermotherapy.

  15. Real-time optoacoustic monitoring of temperature in tissues

    International Nuclear Information System (INIS)

    Larina, Irina V; Larin, Kirill V; Esenaliev, Rinat O

    2005-01-01

    To improve the safety and efficacy of thermal therapy, it is necessary to map tissue temperature in real time with submillimetre spatial resolution. Accurate temperature maps may provide the necessary control of the boundaries of the heated regions and minimize thermal damage to surrounding normal tissues. Current imaging modalities fail to monitor tissue temperature in real time with high resolution and accuracy. We investigated a non-invasive optoacoustic method for accurate, real-time monitoring of tissue temperature during thermotherapy. In this study, we induced temperature gradients in tissue and tissue-like samples and monitored the temperature distribution using the optoacoustic technique. The fundamental harmonic of a Q-switched Nd : YAG laser (λ = 1064 nm) was used for optoacoustic wave generation and probing of tissue temperature. The tissue temperature was also monitored with a multi-sensor temperature probe inserted in the samples. Good agreement between optoacoustically measured and actual tissue temperatures was obtained. The accuracy of temperature monitoring was better than 1 0 C, while the spatial resolution was about 1 mm. These data suggest that the optoacoustic technique has the potential to be used for non-invasive, real-time temperature monitoring during thermotherapy

  16. Low-cost automatic station for compost temperature monitoring

    Directory of Open Access Journals (Sweden)

    Marcelo D. L. Jordão

    Full Text Available ABSTRACT Temperature monitoring is an important procedure to control the composting process. Due to cost limitation, temperature monitoring is manual and with daily sampling resolution. The objective of this study was to develop an automatic station with US$ 150 dollars, able to monitor air temperature at two different points in a compost pile, with a 5-min time resolution. In the calibration test, the sensors showed an estimated uncertainty from ± 1 to ± 1.9 ºC. In the field validation test, the station guaranteed secure autonomy for seven days and endured high humidity and extreme temperature (> 70 °C.

  17. Real-time Thermal Stir Weld Temperature Monitor, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Thermal stir welding (TSW) is a solid state welding process which has shown promise in joining high strength, high temperature metals needed for space launch...

  18. Metal nanoparticle direct inkjet printing for low-temperature 3D micro metal structure fabrication

    International Nuclear Information System (INIS)

    Ko, Seung Hwan; Nam, Koo Hyun; Chung, Jaewon; Hotz, Nico; Grigoropoulos, Costas P

    2010-01-01

    Inkjet printing of functional materials is a key technology toward ultra-low-cost, large-area electronics. We demonstrate low-temperature 3D micro metal structure fabrication by direct inkjet printing of metal nanoparticles (NPs) as a versatile, direct 3D metal structuring approach representing an alternative to conventional vacuum deposition and photolithographic methods. Metal NP ink was inkjet-printed to exploit the large melting temperature drop of the nanomaterial and the ease of the NP ink formulation. Parametric studies on the basic conditions for stable 3D inkjet printing of NP ink were carried out. Furthermore, diverse 3D metal microstructures, including micro metal pillar arrays, helices, zigzag and micro bridges were demonstrated and electrical characterization was performed. Since the process requires low temperature, it carries substantial potential for fabrication of electronics on a plastic substrate

  19. Room temperature creep in metals and alloys

    Energy Technology Data Exchange (ETDEWEB)

    Deibler, Lisa Anne [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Materials Characterization and Performance

    2014-09-01

    Time dependent deformation in the form of creep and stress relaxation is not often considered a factor when designing structural alloy parts for use at room temperature. However, creep and stress relaxation do occur at room temperature (0.09-0.21 Tm for alloys in this report) in structural alloys. This report will summarize the available literature on room temperature creep, present creep data collected on various structural alloys, and finally compare the acquired data to equations used in the literature to model creep behavior. Based on evidence from the literature and fitting of various equations, the mechanism which causes room temperature creep is found to include dislocation generation as well as exhaustion.

  20. Performance of HT9 clad metallic fuel at high temperature

    International Nuclear Information System (INIS)

    Pahl, R.G.; Lahm, C.E.; Hayes, S.L.

    1992-01-01

    Steady-state testing of HT9 clad metallic fuel at high temperatures was initiated in EBR-II in November of 1987. At that time U-10 wt. % Zr fuel clad with the low-swelling ferritic/martensitic alloy HT9 was being considered as driver fuel options for both EBR-II and FFTF. The objective of the X447 test described here was to determine the lifetime of HT9 cladding when operated with metallic fuel at beginning of life inside wall temperatures approaching ∼660 degree C. Though stress-temperature design limits for HT9 preclude its use for high burnup applications under these conditions due to excessive thermal creep, the X447 test was carried out to obtain data on high temperature breach phenomena involving metallic fuel since little data existed in that area

  1. Temperature-dependent liquid metal flowrate control device

    International Nuclear Information System (INIS)

    Carlson, R.D.

    1978-01-01

    A temperature-dependent liquid metal flowrate control device includes a magnet and a ferromagnetic member defining therebetween a flow path for liquid metal, the ferromagnetic member being formed of a material having a curie temperature at which a change in the flow rate of the liquid metal is desired. According to the preferred embodiment the magnet is a cylindrical rod magnet axially disposed within a cylindrical member formed of a curie material and having iron pole pieces at the ends. A cylindrical iron shunt and a thin wall stainless steel barrier are disposed in the annulus between magnet and curie material. Below the curie temperature flow between steel barrier and curie material is impeded and above the curie temperature flow impedance is reduced

  2. Temperature-dependent liquid metal flowrate control device

    Science.gov (United States)

    Carlson, Roger D.

    1978-01-01

    A temperature-dependent liquid metal flowrate control device includes a magnet and a ferromagnetic member defining therebetween a flow path for liquid metal, the ferromagnetic member being formed of a material having a curie temperature at which a change in the flow rate of the liquid metal is desired. According to the preferred embodiment the magnet is a cylindrical rod magnet axially disposed within a cylindrical member formed of a curie material and having iron pole pieces at the ends. A cylindrical iron shunt and a thin wall stainless steel barrier are disposed in the annulus between magnet and curie material. Below the curie temperature flow between steel barrier and curie material is impeded and above the curie temperature flow impedance is reduced.

  3. Tissue temperature monitoring using thermoacoustic and photoacoustic techniques

    Science.gov (United States)

    Pramanik, Manojit; Erpelding, Todd N.; Jankovic, Ladislav; Wang, Lihong V.

    2010-02-01

    Real-time temperature monitoring with high spatial resolution (~1 mm) and high temperature sensitivity (1 °C or better) is needed for the safe deposition of heat energy in surrounding healthy tissue and efficient destruction of tumor and abnormal cells during thermotherapy. A temperature sensing technique using thermoacoustic and photoacoustic measurements combined with a clinical Philips ultrasound imaging system (iU22) has been explored in this study. Using a tissue phantom, this noninvasive method has been demonstrated to have high temporal resolution and temperature sensitivity. Because both photoacoustic and thermoacoustic signal amplitudes depend on the temperature of the source object, the signal amplitudes can be used to monitor the temperature. The signal is proportional to the dimensionless Grueneisen parameter of the object, which in turn varies with the temperature of the object. A temperature sensitivity of 0.5 °C was obtained at a temporal resolution as short as 3.6 s with 50 signal averages.

  4. Perry Nuclear Power Plant Area/Equipment Temperature Monitoring Program

    International Nuclear Information System (INIS)

    McGuire, L.L.

    1991-01-01

    The Perry Nuclear Power Plant Area/Equipment Temperature Monitoring Program serves two purposes. The first is to track temperature trends during normal plant operation in areas where suspected deviations from established environmental profiles exist. This includes the use of Resistance Temperature Detectors, Recorders, and Temperature Dots for evaluation of equipment qualified life for comparison with tested parameters and the established Environmental Design Profile. It also may be used to determine the location and duration of steam leaks for effect on equipment qualified life. The second purpose of this program is to aid HVAC design engineers in determining the source of heat outside anticipated design parameters. Resistance Temperature Detectors, Recorders, and Temperature Dots are also used for this application but the results may include design changes to eliminate the excess heat or provide qualified equipment (cable) to withstand the elevated temperature, splitting of environmental zones to capture accurate temperature parameters, or continued environmental monitoring for evaluation of equipment located in hot spots

  5. Quantum simulation of low-temperature metallic liquid hydrogen

    OpenAIRE

    Chen, Ji; Xin-Zheng, Li; Zhang, Qianfan; Probert, Matt; Pickard, Chris J.; Needs, Richard J.; Michaelides, Angelos; Wang, Enge

    2013-01-01

    Experiments and computer simulations have shown that the melt-ing temperature of solid hydrogen drops with pressure above about 65 GPa, suggesting that a liquid state might exist at low temperatures. It has also been suggested that this low temperature liquid state might be non-molecular and metallic, although evidence for such behaviour is lacking. Here, we report results for hydrogen at high pressures using ab initio path-integral molecular dynamics methods, which include a description of t...

  6. Elevated temperature fatigue testing of metals

    Science.gov (United States)

    Hirschberg, M. H.

    1981-01-01

    The major technology areas needed to perform a life prediction of an aircraft turbine engine hot section component are discussed and the steps required for life prediction are outlined. These include the determination of the operating environment, the calculation of the thermal and mechanical loading of the component, the cyclic stress-strain and creep behavior of the material required for structural analysis, and the structural analysis to determine the local stress-strain-temperature-time response of the material at the critical location in the components. From a knowledge of the fatigue, creep, and failure resistance of the material, a prediction of the life of the component is made. Material characterization and evaluation conducted for the purpose of calculating fatigue crack initiation lives of components operating at elevated temperatures are emphasized.

  7. Utility of Esophageal Temperature Monitoring During Pulmonary Vein Isolation for Atrial Fibrillation Using Duty-Cycled Phased Radiofrequency Ablation

    NARCIS (Netherlands)

    Deneke, Thomas; Bünz, Kathrin; Bastian, Annely; Päsler, Marcus; Anders, Helge; Lehmann, Rainer; Meuser, Wolfgang; de Groot, Joris R.; Horlitz, Marc; Haberkorn, Ron; Mügge, Andreas; Shin, Dong-In

    2011-01-01

    Methods and Results: Ninety consecutive patients undergoing PV-isolation were evaluated. Group A (48 patients) had continuous luminal esophageal temperature (LET) monitoring using a temperature probe with 3 metal electrodes located in the vicinity of the targeted PV ostia. Ablation ceased when LET

  8. Fish product quality evaluation based on temperature monitoring in ...

    African Journals Online (AJOL)

    As one kind of perishable food, fish product is at risk of suffering various damages during cold chain and temperature is the most important factor to affect the product quality. This research work on frozen tilapia fillet was aimed at evaluating the fish product quality and predict shelf-life through monitoring temperature change ...

  9. Design of temperature monitoring system based on CAN bus

    Science.gov (United States)

    Zhang, Li

    2017-10-01

    The remote temperature monitoring system based on the Controller Area Network (CAN) bus is designed to collect the multi-node remote temperature. By using the STM32F103 as main controller and multiple DS18B20s as temperature sensors, the system achieves a master-slave node data acquisition and transmission based on the CAN bus protocol. And making use of the serial port communication technology to communicate with the host computer, the system achieves the function of remote temperature storage, historical data show and the temperature waveform display.

  10. [The development of a respiration and temperature monitor].

    Science.gov (United States)

    Du, X; Wu, B; Liu, Y; He, Q; Xiao, J

    2001-12-01

    This paper introduces the design of a monitoring system to measure the respiration and temperature of a body with an 8Xc196 single-chip microcomputer. This system can measure and display the respiration wave, respiration frequency and the body temperature in real-time with a liquid crystal display (LCD) and give an alarm when the parameters are beyond the normal scope. In addition, this device can provide a 24 hours trend graph of the respiration frequency and the body temperature parameters measured. Data can also be exchanged through serial communication interfaces (RS232) between the PC and the monitor.

  11. High-temperature MEMS Heater Platforms: Long-term Performance of Metal and Semiconductor Heater Materials

    OpenAIRE

    Spannhake, Jan; Schulz, Olaf; Helwig, Andreas; Krenkow, Angelika; M?ller, Gerhard; Doll, Theodor

    2006-01-01

    Micromachined thermal heater platforms offer low electrical power consumption and high modulation speed, i.e. properties which are advantageous for realizing non-dispersive infrared (NDIR) gas- and liquid monitoring systems. In this paper, we report on investigations on silicon-on-insulator (SOI) based infrared (IR) emitter devices heated by employing different kinds of metallic and semiconductor heater materials. Our results clearly reveal the superior high-temperature performance of semicon...

  12. Adaptive ultrasound temperature imaging for monitoring radiofrequency ablation.

    Directory of Open Access Journals (Sweden)

    Yi-Da Liu

    Full Text Available Radiofrequency ablation (RFA has been widely used as an alternative treatment modality for liver tumors. Monitoring the temperature distribution in the tissue during RFA is required to assess the thermal dosage. Ultrasound temperature imaging based on the detection of echo time shifts has received the most attention in the past decade. The coefficient k, connecting the temperature change and the echo time shift, is a medium-dependent parameter used to describe the confounding effects of changes in the speed of sound and thermal expansion as temperature increases. The current algorithm of temperature estimate based on echo time shift detection typically uses a constant k, resulting in estimation errors when ablation temperatures are higher than 50°C. This study proposes an adaptive-k algorithm that enables the automatic adjustment of the coefficient k during ultrasound temperature monitoring of RFA. To verify the proposed algorithm, RFA experiments on in vitro porcine liver samples (total n = 15 were performed using ablation powers of 10, 15, and 20 W. During RFA, a clinical ultrasound system equipped with a 7.5-MHz linear transducer was used to collect backscattered signals for ultrasound temperature imaging using the constant- and adaptive-k algorithms. Concurrently, an infrared imaging system and thermocouples were used to measure surface temperature distribution of the sample and internal ablation temperatures for comparisons with ultrasound estimates. Experimental results demonstrated that the proposed adaptive-k method improved the performance in visualizing the temperature distribution. In particular, the estimation errors were also reduced even when the temperature of the tissue is higher than 50°C. The proposed adaptive-k ultrasound temperature imaging strategy has potential to serve as a thermal dosage evaluation tool for monitoring high-temperature RFA.

  13. Tree rings as monitors of heavy metal air pollution histories

    International Nuclear Information System (INIS)

    Kennedy, G.; Bergeron, S.

    1991-01-01

    The potential of five species of trees as historical monitors of heavy metal air pollution has been investigated. The study was carried out at a site 2 km from an industrial complex including several metal refineries. Using neutron activation, heavy metal concentrations were measured in the xylem as a function of the year of wood formation. The manganese concentrations were by far the highest. In maple trees the high natural level of this essential trace element masked any increases due to pollution. In ash and cedar increased Mn concentrations were found, relative to control trees, but there is evidence for radial translocation. In hemlock the time variations of the average Mn concentrations followed the production rates of the refineries but large variations among individual trees were observed. Hemlock was estimated to accumulate up to 0.3% of the atmospheric Mn input. (author) 13 refs.; 3 figs

  14. In situ temperature monitoring in single-molecule FRET experiments

    Science.gov (United States)

    Hartmann, Andreas; Berndt, Frederic; Ollmann, Simon; Krainer, Georg; Schlierf, Michael

    2018-03-01

    Thermodynamic properties of single molecules including enthalpic and entropic contributions are often determined from experiments by a direct control and precise measurement of the local temperature. However, common temperature monitoring techniques using, for example, ultrafine temperature probes can lead to uncertainties as the probe cannot be placed in the vicinity of the molecule of interest. Here, we devised an approach to measure the local temperature in freely diffusing confocal single-molecule Förster Resonance Energy Transfer (smFRET) experiments in situ by directly adding the temperature-sensitive fluorescent dye Rhodamine B, whose fluorescence lifetime serves as a probe of the local temperature in the confocal volume. We demonstrate that the temperature and FRET efficiencies of static and dynamic molecules can be extracted within one measurement simultaneously, without the need of a reference chamber. We anticipate this technique to be particularly useful in the physicochemical analyses of temperature-dependent biomolecular processes from single-molecule measurements.

  15. Method for low temperature preparation of a noble metal alloy

    Science.gov (United States)

    Even, Jr., William R.

    2002-01-01

    A method for producing fine, essentially contamination free, noble metal alloys is disclosed. The alloys comprise particles in a size range of 5 to 500 nm. The method comprises 1. A method for preparing a noble metal alloy at low temperature, the method comprising the steps of forming solution of organometallic compounds by dissolving the compounds into a quantity of a compatible solvent medium capable of solvating the organometallic, mixing a portion of each solution to provide a desired molarity ratio of ions in the mixed solution, adding a support material, rapidly quenching droplets of the mixed solution to initiate a solute-solvent phase separation as the solvent freezes, removing said liquid cryogen, collecting and freezing drying the frozen droplets to produce a dry powder, and finally reducing the powder to a metal by flowing dry hydrogen over the powder while warming the powder to a temperature of about 150.degree. C.

  16. Silicon Carbide Temperature Monitor Processing Improvements. Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Unruh, Troy Casey [Idaho National Lab. (INL), Idaho Falls, ID (United States); Daw, Joshua Earl [Idaho National Lab. (INL), Idaho Falls, ID (United States); Al Rashdan, Ahamad [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-01-29

    Silicon carbide (SiC) temperature monitors are used as temperature sensors in Advanced Test Reactor (ATR) irradiations at the Idaho National Laboratory (INL). Although thermocouples are typically used to provide real-time temperature indication in instrumented lead tests, other indicators, such as melt wires, are also often included in such tests as an independent technique of detecting peak temperatures incurred during irradiation. In addition, less expensive static capsule tests, which have no leads attached for real-time data transmission, often rely on melt wires as a post-irradiation technique for peak temperature indication. Melt wires are limited in that they can only detect whether a single temperature is or is not exceeded. SiC monitors are advantageous because a single monitor can be used to detect for a range of temperatures that occurred during irradiation. As part of the process initiated to make SiC temperature monitors available at the ATR, post-irradiation evaluations of these monitors have been previously completed at the High Temperature Test Laboratory (HTTL). INL selected the resistance measurement approach for determining irradiation temperature from SiC temperature monitors because it is considered to be the most accurate measurement. The current process involves the repeated annealing of the SiC monitors at incrementally increasing temperature, with resistivity measurements made between annealing steps. The process is time consuming and requires the nearly constant attention of a trained staff member. In addition to the expensive and lengthy post analysis required, the current process adds many potential sources of error in the measurement, as the sensor must be repeatedly moved from furnace to test fixture. This time-consuming post irradiation analysis is a significant portion of the total cost of using these otherwise inexpensive sensors. An additional consideration of this research is that, if the SiC post processing can be automated, it

  17. Disclination mediated dynamic recrystallization in metals at low temperature.

    Science.gov (United States)

    Aramfard, Mohammad; Deng, Chuang

    2015-09-16

    Recrystallization is one of the most important physical phenomena in condensed matter that has been utilized for materials processing for thousands of years in human history. It is generally believed that recrystallization is thermally activated and a minimum temperature must be achieved for the necessary atomic mechanisms to occur. Here, using atomistic simulations, we report a new mechanism of dynamic recrystallization that can operate at temperature as low as T = 10 K in metals during deformation. In contrast to previously proposed dislocation-based models, this mechanism relies on the generation of disclination quadrupoles, which are special defects that form during deformation when the grain boundary migration is restricted by structural defects such as triple junctions, cracks or obstacles. This mechanism offers an alternative explanation for the grain refinement in metals during severe plastic deformation at cryogenic temperature and may suggest a new method to tailor the microstructure in general crystalline materials.

  18. Xenon Recovery at Room Temperature using Metal-Organic Frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Elsaidi, Sameh K. [Physical and Computational Science Directorate, Pacific Northwest National Laboratory, Richland WA 99352 USA; Chemistry Department, Faculty of Science, Alexandria University, P. O. Box 426 Ibrahimia Alexandria 21321 Egypt; Ongari, Daniele [Laboratory of Molecular Simulation, Institut des Sciences et Ingeénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Rue de l' Industrie 17 1951 Sion Valais Switzerland; Xu, Wenqian [X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne IL 60439 USA; Mohamed, Mona H. [Chemistry Department, Faculty of Science, Alexandria University, P. O. Box 426 Ibrahimia Alexandria 21321 Egypt; Haranczyk, Maciej [IMDEA Materials Institute, c/Eric Kandel 2 28906 Getafe, Madrid Spain; Thallapally, Praveen K. [Physical and Computational Science Directorate, Pacific Northwest National Laboratory, Richland WA 99352 USA

    2017-07-24

    Xenon is known to be a very efficient anesthetic gas but its cost prohibits the wider use in medical industry and other potential applications. It has been shown that Xe recovery and recycle from anesthetic gas mixture can significantly reduce its cost as anesthetic. The current technology uses series of adsorbent columns followed by low temperature distillation to recover Xe, which is expensive to use in medical facilities. Herein, we propose much efficient and simpler system to recover and recycle Xe from simulant exhale anesthetic gas mixture at room temperature using metal organic frameworks. Among the MOFs tested, PCN-12 exhibits unprecedented performance with high Xe capacity, Xe/N2 and Xe/O2 selectivity at room temperature. The in-situ synchrotron measurements suggest the Xe is occupied in the small pockets of PCN-12 compared to unsaturated metal centers (UMCs). Computational modeling of adsorption further supports our experimental observation of Xe binding sites in PCN-12.

  19. Monitoring actual temperatures in Susquehanna SES reactor buildings

    International Nuclear Information System (INIS)

    Derkacs, A.P.

    1991-01-01

    PP and L has been monitoring temperatures in the Susquehanna SES reactor building with digital temperature recorders since 1986. In early 1990, data from four representative areas was analyzed to determine the temperature in each area which would produce the same rate of degradation as the distribution of actual temperatures recorded over about 40 months. From these effective average temperatures, qualified life multipliers were determined for activation energies in the range of 0.5 to 1.5 and those multipliers were used to estimate new qualified lives and the number of replacements which might be saved during the life of the plant. The results indicate that pursuing a program of determining EQ qualified lives from actual temperatures, rather than maximum design basis temperatures, will provide a substantial payback in reduced EQ driven maintenance

  20. 1997 Performance Testing of Multi-Metal Continuous Emissions Monitors

    Energy Technology Data Exchange (ETDEWEB)

    Sky +, Inc.

    1998-09-01

    Five prototype and two commercially available multi-metals continuous emissions monitors (CEMs) were tested in September 1997 at the Rotary Kiln Incinerator Simulator facility at the EPA National Risk Management Research Laboratory, Research Triangle Park, North Carolina. The seven CEMs were tested side by side in a long section of duct following the secondary combustion chamber of the RKIS. Two different concentrations of six toxic metals were introduced into the incinerator-approximately 15 and 75 µg/dscm of arsenic, beryllium, cadmium, chromium, lead, and mercury (We also tested for antimony but we are not reporting on it here because EPA recently dropped antimony from the list of metals addressed by the draft MACT rule). These concentrations were chosen to be close to emission standards in the draft MACT rule and the estimated Method Detection Limit (MDL) required of a CEM for regulatory compliance purposes. Results from this test show that no CEMs currently meet the performance specifications in the EPA draft MACT rule for hazardous waste incinerators. Only one of the CEMs tested was able to measure all six metals at the concentrations tested. Even so, the relative accuracy of this CEM varied between 35% and 100%, not 20% or less as required in the EPA performance specification. As a result, we conclude that no CEM is ready for long-term performance validation for compliance monitoring applications. Because sampling and measuring Hg is a recurring problem for multi-metal CEMs as well as Hg CEMs, we recommended that developers participate in a 1998 DOE-sponsored workshop to solve these and other common CEM measurement issues.

  1. Femtosecond differential transmission measurements on low temperature GaAs metal-semiconductor-metal structures

    DEFF Research Database (Denmark)

    Keil, Ulrich Dieter Felix; Hvam, Jørn Märcher; Tautz, S.

    1997-01-01

    We report on differential transmission measurements on low temperature grown (LT)-GaAs with and without applied electrical fields at different wavelengths. Electrical fields up to 100 kV/cm can be applied via an interdigitated contact structure to our LT GaAs samples which have been removed from....... The response time of a biased metal-semiconductor-metal detector, therefore, exceeds the carrier life time of the substrate material. (C) 1997 American Institute of Physics....

  2. Hanford coring bit temperature monitor development testing results report

    International Nuclear Information System (INIS)

    Rey, D.

    1995-05-01

    Instrumentation which directly monitors the temperature of a coring bit used to retrieve core samples of high level nuclear waste stored in tanks at Hanford was developed at Sandia National Laboratories. Monitoring the temperature of the coring bit is desired to enhance the safety of the coring operations. A unique application of mature technologies was used to accomplish the measurement. This report documents the results of development testing performed at Sandia to assure the instrumentation will withstand the severe environments present in the waste tanks

  3. Problems concerned with scrap metal monitoring at borders

    International Nuclear Information System (INIS)

    Duftschmid, K.E.

    1997-01-01

    Since the early 1980's numerous incidents have been reported in which radioactive material or empty labelled containers for radioactive sources have been found in scrap metal. Apart from the potential health hazard to employees and the general public resulting costs for decontamination, shutdown of production and waste of products already amounted to multi-million dollar figures. Since the opening of the ''iron border'' in Europe, incidents of illicit trafficking of radioactive sources across borders and contamination of scrap metal imported from the former ''Eastern Countries'' have considerably increased, as a result of the lack of a suitable radiation protection infrastructure in some of these countries. This initiated monitoring of scrap metal transports at the borders of several European countries, such as Austria, Finland, Germany and Italy. Up to now neither universally accepted clearance levels for scrap contamination, nor an agreed standardised procedure for its control exist, although the IAEA as well as the European Commission have proposed some recommendations. As a pragmatic solution for border monitoring it is suggested to apply, as practical clearance level, a dose rate on the outside of the vehicle in the order of 0,1 μSv/h, which is approximately equivalent to double natural environmental background. This dose rate would correspond to an activity concentration for 60 Co in the order of 1 kBq/kg and therefore be in a tolerable range, even in view of products coming in close contact with the public. (author)

  4. High temperature strain of metals and alloys. Physical fundamentals

    Energy Technology Data Exchange (ETDEWEB)

    Levitin, V. [National Technical Univ., Zaporozhye (Ukraine)

    2006-07-01

    The author shows how new in-situ X-ray investigations and transmission electron microscope studies lead to novel explanations of high-temperature deformation and creep in pure metals, solid solutions and super alloys. This approach is the first to find unequivocal and quantitative expressions for the macroscopic deformation rate by means of three groups of parameters: substructural characteristics, physical material constants and external conditions. Creep strength of the studied uptodate single crystal super alloys is greatly increased over conventional polycrystalline super alloys. The contents of this book include: macroscopic characteristics of strain at high temperatures; experimental equipment and technique of in situ X-ray investigations; experimental data and structural parameters in deformed metals; sub-boundaries as dislocation sources and obstacles; the physical mechanism of creep and the quantitative structural model; simulation of the parameters evolution; system of differential equations; high-temperature deformation of industrial super alloys; single crystals of super alloys; effect of composition, orientation and temperature on properties; and creep of some refractory metals.

  5. Quantum Efficiency as a Function of Temperature in Metal Photocathodes

    Science.gov (United States)

    2013-06-01

    Temperature monitoring programs. .................................................... 21  Figure 12.  Laser system in aluminum enclosure... antimonides and alkali tellurides, are the primary electron sources for many accelerators, and they are now in operation at the Thomas Jefferson National... aluminum enclosure, which surrounded the high- voltage end of the test stand as well as the laser head, to protect us not only from the hazard of UV

  6. Sleep monitoring sensor using flexible metal strain gauge

    Science.gov (United States)

    Kwak, Yeon Hwa; Kim, Jinyong; Kim, Kunnyun

    2018-05-01

    This paper presents a sleep monitoring sensor based on a flexible metal strain gauge. As quality of life has improved, interest in sleep quality, and related products, has increased. In this study, unlike a conventional single sensor based on a piezoelectric material, a metal strain gauge-based array sensor based on polyimide and nickel chromium (NiCr) is applied to provide movement direction, respiration, and heartbeat data as well as contact-free use by the user during sleeping. Thin-film-type resistive strain gage sensors are fabricated through the conventional flexible printed circuit board (FPCB) process, which is very useful for commercialization. The measurement of movement direction and respiratory rate during sleep were evaluated, and the heart rate data were compared with concurrent electrocardiogram (ECG) data. An algorithm for analyzing sleep data was developed using MATLAB, and the error rate was 4.2% when compared with ECG for heart rate.

  7. Intra-hole fluid convection: High-resolution temperature monitoring

    Czech Academy of Sciences Publication Activity Database

    Čermák, Vladimír; Šafanda, Jan; Krešl, Milan

    2008-01-01

    Roč. 348, č. 3-4 (2008), s. 464-479 ISSN 0022-1694 Institutional research plan: CEZ:AV0Z30120515 Keywords : temperature monitoring * convection * fluid dynamics * borehole logging Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 2.305, year: 2008

  8. Temperature dependence of contact resistance at metal/MWNT interface

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang-Eui; Moon, Kyoung-Seok; Sohn, Yoonchul, E-mail: yoonchul.son@samsung.com [Materials Research Center, Samsung Advanced Institute of Technology, Samsung Electronics, Suwon 443-803 (Korea, Republic of)

    2016-07-11

    Although contact resistance of carbon nanotube (CNT) is one of the most important factors for practical application of electronic devices, a study regarding temperature dependence on contact resistance of CNTs with metal electrodes has not been found. Here, we report an investigation of contact resistance at multiwalled nanotube (MWNT)/Ag interface as a function of temperature, using MWNT/polydimethylsiloxane (PDMS) composite. Electrical resistance of MWNT/PDMS composite revealed negative temperature coefficient (NTC). Excluding the contact resistance with Ag electrode, the NTC effect became less pronounced, showing lower intrinsic resistivity with the activation energy of 0.019 eV. Activation energy of the contact resistance of MWNT/Ag interface was determined to be 0.04 eV, two times larger than that of MWNT-MWNT network. The increase in the thermal fluctuation assisted electron tunneling is attributed to conductivity enhancement at both MWNT/MWNT and MWNT/Ag interfaces with increasing temperature.

  9. The temperature variation of hydrogen diffusion coefficients in metal alloys

    Science.gov (United States)

    Danford, M. D.

    1990-01-01

    Hydrogen diffusion coefficients were measured as a function of temperature for a few metal alloys using an electrochemical evolution technique. Results from these measurements are compared to those obtained by the time-lag method. In all cases, diffusion coefficients obtained by the electrochemical method are larger than those by the time-lag method by an order of magnitude or more. These differences are attributed mainly to hydrogen trapping.

  10. Monitoring of temperature gradient development of highway concrete bridge

    Directory of Open Access Journals (Sweden)

    Krkoska Lukas

    2017-01-01

    Full Text Available Thermal effect is one of very important from the large bridge design procedure point of view. Especially vertical temperature gradient is being crucial. There were realized some research works of the thermal effects monitoring on the concrete bridges in the world. More of them were performed in the USA but only a few at European bridges. The short overview of our long-term monitoring of the temperature load on chosen concrete bridge is presented in this paper. We decided to analyse one concrete box girder bridge that was built by incremental launching method on highway D1 at Slovakia near Zilina city. Recorded temperature gradient was compared with thermal gradients for the concrete box girder bridge recommended by EC 1991-1-5 design specifications.

  11. Experimental determination of the temperature dependence of metallic work functions at low temperatures. Progress report

    International Nuclear Information System (INIS)

    Pipes, P.B.

    1977-01-01

    Progress made under ERDA Contract No. EY-76-S-02-2314.002 is described. Efforts to gain theoretical insight into the temperature dependence of the contact potential of Nb near the superconducting transition have only been qualitatively successful. Preliminary measurements of adsorbed 4 He gas on the temperature dependence of the contact potentials of metals were performed and compared with a previously developed theory

  12. Metal/Silicate Partitioning at High Pressures and Temperatures

    Science.gov (United States)

    Shofner, G.; Campbell, A.; Danielson, L.; Righter, K.; Rahman, Z.

    2010-01-01

    The behavior of siderophile elements during metal-silicate segregation, and their resulting distributions provide insight into core formation processes. Determination of partition coefficients allows the calculation of element distributions that can be compared to established values of element abundances in the silicate (mantle) and metallic (core) portions of the Earth. Moderately siderophile elements, including W, are particularly useful in constraining core formation conditions because they are sensitive to variations in T, P, oxygen fugacity (fO2), and silicate composition. To constrain the effect of pressure on W metal/silicate partitioning, we performed experiments at high pressures and temperatures using a multi anvil press (MAP) at NASA Johnson Space Center and laser-heated diamond anvil cells (LHDAC) at the University of Maryland. Starting materials consisted of natural peridotite mixed with Fe and W metals. Pressure conditions in the MAP experiments ranged from 10 to 16 GPa at 2400 K. Pressures in the LHDAC experiments ranged from 26 to 58 GPa, and peak temperatures ranged up to 5000 K. LHDAC experimental run products were sectioned by focused ion beam (FIB) at NASA JSC. Run products were analyzed by electron microprobe using wavelength dispersive spectroscopy. Liquid metal/liquid silicate partition coefficients for W were calculated from element abundances determined by microprobe analyses, and corrected to a common fO2 condition of IW-2 assuming +4 valence for W. Within analytical uncertainties, W partitioning shows a flat trend with increasing pressure from 10 to 16 GPa. At higher pressures, W becomes more siderophile, with an increase in partition coefficient of approximately 0.5 log units.

  13. Low Temperature Growth of Nanostructured Diamond Films on Metals

    Science.gov (United States)

    Baker, Paul A.; Catledge, Shane A.; Vohra, Yogesh K.

    2001-01-01

    The field of nanocrystalline diamond and tetrahedral amorphous carbon films has been the focus of intense experimental activity in the last few years for applications in field emission display devices, optical windows, and tribological coatings, The choice of substrate used in most studies has typically been silicon. For metals, however, the thermal expansion mismatch between the diamond film and substrate gives rise to thermal stress that often results in delamination of the film. To avoid this problem in conventional CVD deposition low substrate temperatures (less than 700 C) have been used, often with the incorporation of oxygen or carbon monoxide to the feedgas mixture. Conventionally grown CVD diamond films are also rough and would require post-deposition polishing for most applications. Therefore, there is an obvious need to develop techniques for deposition of well-adhered, smooth nano-structured diamond films on metals for various tribological applications. In our work, nanostructured diamond films are grown on a titanium alloy substrate using a two-step deposition process. The first step is performed at elevated temperature (820 C) for 30 minutes using a H2/CH4/N2 gas mixture in order to grow a thin (approx. 600 nm) nanostructured diamond layer and improve film adhesion. The remainder of the deposition involves growth at low temperature (less than 600 C) in a H2/CH4/O2 gas mixture. Laser reflectance Interferometry (LRI) pattern during growth of a nanostructured diamond film on Ti-6Al-4V alloy. The first 30 minutes are at a high temperature of 820 C and the rest of the film is grown at a low temperature of 580 T. The fringe pattern is observed till the very end due to extremely low surface roughness of 40 nm. The continuation of the smooth nanostructured diamond film growth during low temperature deposition is confirmed by in-situ laser reflectance interferometry and by post-deposition micro-Raman spectroscopy and surface profilometry. Similar experiments

  14. In Situ Monitoring of Temperature inside Lithium-Ion Batteries by Flexible Micro Temperature Sensors

    Directory of Open Access Journals (Sweden)

    Pei-Chi Chen

    2011-10-01

    Full Text Available Lithium-ion secondary batteries are commonly used in electric vehicles, smart phones, personal digital assistants (PDA, notebooks and electric cars. These lithium-ion secondary batteries must charge and discharge rapidly, causing the interior temperature to rise quickly, raising a safety issue. Over-charging results in an unstable voltage and current, causing potential safety problems, such as thermal runaways and explosions. Thus, a micro flexible temperature sensor for the in in-situ monitoring of temperature inside a lithium-ion secondary battery must be developed. In this work, flexible micro temperature sensors were integrated into a lithium-ion secondary battery using the micro-electro-mechanical systems (MEMS process for monitoring temperature in situ.

  15. In situ monitoring of temperature inside lithium-ion batteries by flexible micro temperature sensors.

    Science.gov (United States)

    Lee, Chi-Yuan; Lee, Shuo-Jen; Tang, Ming-Shao; Chen, Pei-Chi

    2011-01-01

    Lithium-ion secondary batteries are commonly used in electric vehicles, smart phones, personal digital assistants (PDA), notebooks and electric cars. These lithium-ion secondary batteries must charge and discharge rapidly, causing the interior temperature to rise quickly, raising a safety issue. Over-charging results in an unstable voltage and current, causing potential safety problems, such as thermal runaways and explosions. Thus, a micro flexible temperature sensor for the in in-situ monitoring of temperature inside a lithium-ion secondary battery must be developed. In this work, flexible micro temperature sensors were integrated into a lithium-ion secondary battery using the micro-electro-mechanical systems (MEMS) process for monitoring temperature in situ.

  16. Mathematical model of the metal mould surface temperature optimization

    International Nuclear Information System (INIS)

    Mlynek, Jaroslav; Knobloch, Roman; Srb, Radek

    2015-01-01

    The article is focused on the problem of generating a uniform temperature field on the inner surface of shell metal moulds. Such moulds are used e.g. in the automotive industry for artificial leather production. To produce artificial leather with uniform surface structure and colour shade the temperature on the inner surface of the mould has to be as homogeneous as possible. The heating of the mould is realized by infrared heaters located above the outer mould surface. The conceived mathematical model allows us to optimize the locations of infrared heaters over the mould, so that approximately uniform heat radiation intensity is generated. A version of differential evolution algorithm programmed in Matlab development environment was created by the authors for the optimization process. For temperate calculations software system ANSYS was used. A practical example of optimization of heaters locations and calculation of the temperature of the mould is included at the end of the article

  17. Effect of temperature on swelling and bubble growth in metals

    International Nuclear Information System (INIS)

    Tiwari, G.P.

    1982-01-01

    The effect of temperature on the swelling of copper-boron alloys has been studied in the temperature range of 900-1040deg C. It is observed that beyond 1030deg C, swelling as well as the rate of bubble growth decrease. Similar characteristics of the bubble growth have been observed in aluminium-boron alloys also. At 590deg C, the bubble growth in aluminium-boron alloys is faster as compared to that at 640deg C. It thus appears that the swelling as well as the growth of the gas bubble are retarded at temperatures near the melting point in metals. Possible reasons for this kind of behaviour are discussed. (author)

  18. High Temperature Transducers for Online Monitoring of Microstructure Evolution

    Energy Technology Data Exchange (ETDEWEB)

    Lissenden, Cliff [Pennsylvania State Univ., State College, PA (United States); Tittmann, Bernhard [Battelle Energy Alliance, LLC, Idaho Falls, ID (United States)

    2015-03-30

    A critical technology gap exists relative to online condition monitoring (CM) of advanced nuclear plant components for damage accumulation; there are not capable sensors and infrastructure available for the high temperature environment. The sensory system, monitoring methodology, data acquisition, and damage characterization algorithm that comprise a CM system are investigated here. Thus this work supports the DOE mission to develop a fundamental understanding of advanced sensors to improve physical measurement accuracy and reduce uncertainty. The research involves a concept viability assessment, a detailed technology gap analysis, and a technology development roadmap.

  19. New cryogenic temperature monitor: PLT-HPT-32

    Science.gov (United States)

    Viera Curbelo, Teodora Aleida; Martín-Fernández, Sergio Gonzáles; Hoyland, R.; Vega-Moreno, A.; Cozar Castellano, Juan; Gómez Reñasco, M. F.; Aguiar-González, M.; Pérez de Taoro, Angeles; Sánchez-de la Rosa, V.; Rubiño-Martín, J. A.; Génova-Santos, R.

    2016-07-01

    The PLT-HPT-32, a new cryogenic temperature monitor, has been developed by the Institute of Astrophysics of the Canary Islands (IAC) and an external engineering company (Sergio González Martín-Fernandez). The PLT-HPT-32 temperature monitor offers precision measurement in a wide range of cryogenic and higher-temperature applications with the ability to easily monitor up to 32 sensor channels. It provides better measurement performance in applications where researchers need to ensure accuracy and precision in their low cryogenic temperature monitoring. The PLT-HPT-32 supports PTC RTDs such as platinum sensors, and diodes such as the Lake Shore DT-670 Series. Used with silicon diodes, it provides accurate measurements in cryo-cooler applications from 16 K to above room temperature. The resolution of the measurement is less than 0.1K. Measurements can be displayed in voltage units or Kelvin units. For it, two different tables can be used. One can be programmed by the user, and the other one corresponds to Lake Shore DT670 sensor that comes standard. There are two modes of measuring, the instantaneous mode and averaged mode. In this moment, all channels must work in the same mode but in the near future it expected to be used in blocks of eight channels. The instantaneous mode takes three seconds to read all channels. The averaged mode takes one minute to average twenty samples in all channels. Alarm thresholds can be configured independently for each input. The alarm events, come from the first eight channels, can activate the unit's relay outputs for hard-wired triggering of other systems or audible annunciators. Activate relays on high, low, or both alarms for any input. For local monitoring, "Stand-Alone Mode", the front panel of the PLT-HPT-32 features a bright liquid crystal display with an LED backlight that shows up to 32 readings simultaneously. Plus, monitoring can be done over a network "Remote Control Mode". Using the Ethernet port on the PLT-HPT-32, you

  20. Near-infrared two-color pyrometer for determining ignition temperatures of metals and metal alloys

    Science.gov (United States)

    Nguyen, K.; Branch, M. C.

    1985-01-01

    A two-color pyrometer has been designed, constructed, and used to measure the ignition temperatures of metals and metal alloys. Cylindrical metal and metal alloy specimens were ignited by a focused cw CO2 laser beam in a cool, static, pure oxygen environment. The pyrometer operates in the near-infrared at two narrow spectral regions, with a nominal bandwidth of 10 nm centered at 0.9051 and 1.06 micron, and has a temperature range from 1000 to 4000 K. In the present design the temperature of a spot, about 0.5 mm in diameter, can be recorded with a maximum time resolution of 25 microseconds and with an accuracy of a few percent. Results of CO2 laser ignition of cylindrical specimens of 6061 aluminum alloy and 302 SS in a pure oxygen environment were obtained from the two-color pyrometer and were compared with those obtained from a thermocouple placed inside the specimen near the laser-irradiated surface.

  1. Continuous monitoring of fumarole temperatures at Mount Etna (Italy)

    Science.gov (United States)

    Madonia, Paolo; Rizzo, Andrea L.; Diliberto, Iole S.; Favara, Rocco

    2013-05-01

    In this paper we present the first data of temperature continuously recorded in two fumarole fields (designated VOR and HOR) located in the summit area of Mount Etna volcano (Italy). The time series embraces two distinct periods: (1) October 2007 to November 2009, during which an effusive eruption occurred from May 2008 to July 2009, and (2) November 2011 to June 2012, characterized by the occurrence of strong paroxysms (fire fountains and lava flow). The analysis of the temperature signal in both the time and frequency domains, and its comparison with meteorological observations allowed us to separate the exogenous influences from the effects of variations in the activity state of the volcano. The acquired data were weakly affected by seasonal cycles of the air temperature and strongly affected by the rainfall. Optimization of site conditions (i.e., sensor depth and soil permeability) markedly reduced meteorological disturbances. The distance from the main degassing and/or eruptive fractures was crucial to maximizing the probability of the technical survival of the monitoring apparatus, which was seriously affected by the emission of acidic gases, tephra fallout, and lava flows. Apart from the exogenous influences, the most appreciable variation was observed at VOR, where a huge increase in fumarole temperature was detected immediately after the onset of the 2008-2009 eruption. Such an anomalous increase was attributed to the rapid ascent of magma feeding the eruptive fracture. Another abrupt increase in temperature was recorded at HOR in March and April 2012. During this period the frequency of paroxysm occurrence increased markedly, and this led us to hypothesize that the thermal anomaly was due to the intrusion of a new batch of magma in the conduits of the southeast crater. Medium- to long-term monitoring (weeks to months) of fumarole temperatures revealed variations that were attributed to pressurization/depressurization phases of the shallow volcanic system

  2. Miniaturized Planar Room Temperature Ionic Liquid Electrochemical Gas Sensor for Rapid Multiple Gas Pollutants Monitoring.

    Science.gov (United States)

    Wan, Hao; Yin, Heyu; Lin, Lu; Zeng, Xiangqun; Mason, Andrew J

    2018-02-01

    The growing impact of airborne pollutants and explosive gases on human health and occupational safety has escalated the demand of sensors to monitor hazardous gases. This paper presents a new miniaturized planar electrochemical gas sensor for rapid measurement of multiple gaseous hazards. The gas sensor features a porous polytetrafluoroethylene substrate that enables fast gas diffusion and room temperature ionic liquid as the electrolyte. Metal sputtering was utilized for platinum electrodes fabrication to enhance adhesion between the electrodes and the substrate. Together with carefully selected electrochemical methods, the miniaturized gas sensor is capable of measuring multiple gases including oxygen, methane, ozone and sulfur dioxide that are important to human health and safety. Compared to its manually-assembled Clark-cell predecessor, this sensor provides better sensitivity, linearity and repeatability, as validated for oxygen monitoring. With solid performance, fast response and miniaturized size, this sensor is promising for deployment in wearable devices for real-time point-of-exposure gas pollutant monitoring.

  3. Release of gases from uranium metal at high temperatures

    International Nuclear Information System (INIS)

    Sayi, Y.S.; Ramanjaneyulu, P.S.; Yadav, C.S.; Shankaran, P.S.; Chhapru, G.C.; Ramakumar, K.L.; Venugopal, V.

    2008-01-01

    Depending on the ambient environmental conditions, different gaseous species could get entrapped in uranium metal ingots or pellets. On heating, melting or vapourising uranium metal, these get released and depending on the composition, may cause detrimental effects either within the metal matrix itself or on the surrounding materials/environment. For instance, these gases may affect the performance of the uranium metal, which is used as fuel in the heavy water moderated research reactors, CIRUS and DHRUVA. Hence, detailed investigations have been carried out on the release of gases over a temperature range 875-1500 K employing hot vacuum extraction technique, in specimen uranium pellets made from uranium rods/ingots. Employing an on-line quadrupole mass spectrometer, the analysis of released gases was carried out. The isobaric interference between carbon monoxide and nitrogen at m/e = 28 in the mass spectrometric analysis has been resolved by considering their fragmentation patterns. Since no standards are available to evaluate the results, only the reproducibility is tested. The precision (relative standard deviation at 3σ level) of the method is ±5%. The minimum detectable gas content employing the method is 5.00 x 10 -09 m 3 . About 4 x 10 -04 m 3 /kg of gas is released from uranium pellets, with hydrogen as the main constituent. The gas content increases with storage in air

  4. Precision temperature monitoring (PTM) and Humidity monitoring (HM) sensors of the CMS electromagnetic calorimeter

    CERN Multimedia

    2006-01-01

    A major aspect for the ECAL detector control is the monitoring of the system temperature and the verification that the required temperature stability of the crystal volume and the APDs, expected to be (18 ± 0.05)C, is achieved. The PTM is designed to read out thermistors, placed on both the front and back of the crystals, with a relative precision better than 0.01 C. In total there are ten sensors per supermodule. The humidity level in the electronics compartment is monitored by the HM system and consists of one humidity sensor per module.

  5. Test plan for core sampling drill bit temperature monitor

    International Nuclear Information System (INIS)

    Francis, P.M.

    1994-01-01

    At WHC, one of the functions of the Tank Waste Remediation System division is sampling waste tanks to characterize their contents. The push-mode core sampling truck is currently used to take samples of liquid and sludge. Sampling of tanks containing hard salt cake is to be performed with the rotary-mode core sampling system, consisting of the core sample truck, mobile exhauster unit, and ancillary subsystems. When drilling through the salt cake material, friction and heat can be generated in the drill bit. Based upon tank safety reviews, it has been determined that the drill bit temperature must not exceed 180 C, due to the potential reactivity of tank contents at this temperature. Consequently, a drill bit temperature limit of 150 C was established for operation of the core sample truck to have an adequate margin of safety. Unpredictable factors, such as localized heating, cause this buffer to be so great. The most desirable safeguard against exceeding this threshold is bit temperature monitoring . This document describes the recommended plan for testing the prototype of a drill bit temperature monitor developed for core sampling by Sandia National Labs. The device will be tested at their facilities. This test plan documents the tests that Westinghouse Hanford Company considers necessary for effective testing of the system

  6. Remote temperature monitoring and electronic identification in food animals

    Energy Technology Data Exchange (ETDEWEB)

    Seawright, G.L.; Holm, D.M.; Sanders, W.M.

    1977-01-01

    Two radiotelemetric systems were developed for remote monitoring of body temperature in livestock. A battery-powered transmitter system was developed as a laboratory tool for remote continuous monitoring of ear-canal temperatures in animals used in vaccine trials and in studies of livestock diseases. An automated data-recording and processing system was also developed. Pilot studies in cattle indicate that the system will be a valuable quantitative tool for vaccine testing and animal experiments. A second telemetry system was developed for widescale use in the livestock industry. It relies on an implantable passive (no batteries) transponder that is energized by an external source of microwaves to transmit temperature and decimal digit identification to a remote receiver. The animal identification feature, coupled with computers, offers the livestock producer unprecedented capabilities for efficient management of his operation. The temperature feature of transponders can aid in disease detection and control, disease diagnosis, and stress and ovulation detection. Its use for identifying temperature markers in disease and stress-tolerent breeding stock may be valuable in selective breeding programs.

  7. A New Wireless Biosensor for Intra-Vaginal Temperature Monitoring

    Directory of Open Access Journals (Sweden)

    Isabel de la Torre

    2010-11-01

    Full Text Available Wireless Body Sensors for medical purposes offer valuable contributions to improve patients’ healthcare, including diagnosis and/or therapeutics monitoring. Body temperature is a crucial parameter in healthcare diagnosis. In gynecology and obstetrics it is measured at the skin’s surface, which is very influenced by the environment. This paper proposes a new intra-body sensor for long-term intra-vaginal temperature collection. The embedded IEEE 802.15.4 communication module allows the integration of this sensor in a Wireless Sensor Network (WSN for remote data access and monitoring. We present the sensor architecture, the construction of the corresponding testbed, and its performance evaluation. This sensor may be used in different medical applications, including preterm labor prevention and fertility and ovulation period detection. The features of the constructed testbed were validated in laboratory tests verifying its accuracy and performance.

  8. Advanced targeted monitoring of high temperature components in power plants

    Energy Technology Data Exchange (ETDEWEB)

    Roos, E.; Maile, K.; Jovanovic, A. [MPA Stuttgart (Germany)

    1998-12-31

    The article presents the idea of targeted monitoring of high-temperature pressurized components in fossil-fueled power plants, implemented within a modular software system and using, in addition to pressure and temperature data, also displacement and strain measurement data. The concept has been implemented as a part of a more complex company-oriented Internet/Intranet system of MPA Stuttgart (ALIAS). ALIAS enables to combine smoothly the monitoring results with those of the off-line analysis, e. g. sensitivity analyses, comparison with preceding experience (case studies), literature search, search in material databases -(experimental and standard data), nonlinear FE-analysis, etc. The concept and the system have been implemented in real plant conditions several power plants in Germany and Europe: one of these applications and its results are described more in detail in the presentation. (orig.) 9 refs.

  9. Xenon Recovery at Room Temperature using Metal-Organic Frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Elsaidi, Sameh K. [Physical and Computational Science Directorate, Pacific Northwest National Laboratory, Richland WA 99352 USA; Chemistry Department, Faculty of Science, Alexandria University, P. O. Box 426 Ibrahimia Alexandria 21321 Egypt; Ongari, Daniele [Laboratory of Molecular Simulation, Institut des Sciences et Ingeénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Rue de l' Industrie 17 1951 Sion Valais Switzerland; Xu, Wenqian [X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne IL 60439 USA; Mohamed, Mona H. [Chemistry Department, Faculty of Science, Alexandria University, P. O. Box 426 Ibrahimia Alexandria 21321 Egypt; Haranczyk, Maciej [IMDEA Materials Institute, c/Eric Kandel 2 28906 Getafe, Madrid Spain; Thallapally, Praveen K. [Physical and Computational Science Directorate, Pacific Northwest National Laboratory, Richland WA 99352 USA

    2017-07-24

    Xenon is known to be a very efficient anesthetic gas but its cost prohibits the wider use in medical industry and other potential applications. It has been shown that Xe recovery and recycle from anesthetic gas mixture can significantly reduce its cost as anesthetic. The current technology uses series of adsorbent columns followed by low temperature distillation to recover Xe, which is expensive to use in medical facilities. Herein, we propose much efficient and simpler system to recover and recycle Xe from simulant exhale anesthetic gas mixture at room temperature using metal organic frameworks. Among the MOFs tested, PCN-12 exhibits unprecedented performance with high Xe capacity, Xe/O2, Xe/N2 and Xe/CO2 selectivity at room temperature. The in-situ synchrotron measurements suggest the Xe is occupied in the small pockets of PCN-12 compared to unsaturated metal centers (UMCs). Computational modeling of adsorption further supports our experimental observation of Xe binding sites in PCN-12.

  10. High-temperature MEMS Heater Platforms: Long-term Performance of Metal and Semiconductor Heater Materials

    Directory of Open Access Journals (Sweden)

    Theodor Doll

    2006-04-01

    Full Text Available Micromachined thermal heater platforms offer low electrical power consumptionand high modulation speed, i.e. properties which are advantageous for realizing non-dispersive infrared (NDIR gas- and liquid monitoring systems. In this paper, we report oninvestigations on silicon-on-insulator (SOI based infrared (IR emitter devices heated byemploying different kinds of metallic and semiconductor heater materials. Our resultsclearly reveal the superior high-temperature performance of semiconductor over metallicheater materials. Long-term stable emitter operation in the vicinity of 1300 K could beattained using heavily antimony-doped tin dioxide (SnO2:Sb heater elements.

  11. Void growth and coalescence in metals deformed at elevated temperature

    DEFF Research Database (Denmark)

    Klöcker, H.; Tvergaard, Viggo

    2000-01-01

    For metals deformed at elevated temperatures the growth of voids to coalescence is studied numerically. The voids are assumed to be present from the beginning of deformation, and the rate of deformation considered is so high that void growth is dominated by power law creep of the material, without...... any noticeable effect of surface diffusion. Axisymmetric unit cell model computations are used to study void growth in a material containing a periodic array of voids, and the onset of the coalescence process is defined as the stage where plastic flow localizes in the ligaments between neighbouring...

  12. Platinum redispersion on metal oxides in low temperature fuel cells.

    Science.gov (United States)

    Tripković, Vladimir; Cerri, Isotta; Nagami, Tetsuo; Bligaard, Thomas; Rossmeisl, Jan

    2013-03-07

    We have analyzed the aptitude of several metal oxide supports (TiO(2), SnO(2), NbO(2), ZrO(2), SiO(2), Ta(2)O(5) and Nb(2)O(5)) to redisperse platinum under electrochemical conditions pertinent to the Proton Exchange Membrane Fuel Cell (PEMFC) cathode. The redispersion on oxide supports in air has been studied in detail; however, due to different operating conditions it is not straightforward to link the chemical and the electrochemical environment. The largest differences reflect in (1) the oxidation state of the surface (the oxygen species coverage), (2) temperature and (3) the possibility of platinum dissolution at high potentials and the interference of redispersion with normal working potential of the PEMFC cathode. We have calculated the PtO(x) (x = 0, 1, 2) adsorption energies on different metal oxides' surface terminations as well as inside the metal oxides' bulk, and we have concluded that NbO(2) might be a good support for platinum redispersion at PEMFC cathodes.

  13. Selective and low temperature transition metal intercalation in layered tellurides

    Science.gov (United States)

    Yajima, Takeshi; Koshiko, Masaki; Zhang, Yaoqing; Oguchi, Tamio; Yu, Wen; Kato, Daichi; Kobayashi, Yoji; Orikasa, Yuki; Yamamoto, Takafumi; Uchimoto, Yoshiharu; Green, Mark A.; Kageyama, Hiroshi

    2016-12-01

    Layered materials embrace rich intercalation reactions to accommodate high concentrations of foreign species within their structures, and find many applications spanning from energy storage, ion exchange to secondary batteries. Light alkali metals are generally most easily intercalated due to their light mass, high charge/volume ratio and in many cases strong reducing properties. An evolving area of materials chemistry, however, is to capture metals selectively, which is of technological and environmental significance but rather unexplored. Here we show that the layered telluride T2PTe2 (T=Ti, Zr) displays exclusive insertion of transition metals (for example, Cd, Zn) as opposed to alkali cations, with tetrahedral coordination preference to tellurium. Interestingly, the intercalation reactions proceed in solid state and at surprisingly low temperatures (for example, 80 °C for cadmium in Ti2PTe2). The current method of controlling selectivity provides opportunities in the search for new materials for various applications that used to be possible only in a liquid.

  14. Selective and low temperature transition metal intercalation in layered tellurides

    Science.gov (United States)

    Yajima, Takeshi; Koshiko, Masaki; Zhang, Yaoqing; Oguchi, Tamio; Yu, Wen; Kato, Daichi; Kobayashi, Yoji; Orikasa, Yuki; Yamamoto, Takafumi; Uchimoto, Yoshiharu; Green, Mark A.; Kageyama, Hiroshi

    2016-01-01

    Layered materials embrace rich intercalation reactions to accommodate high concentrations of foreign species within their structures, and find many applications spanning from energy storage, ion exchange to secondary batteries. Light alkali metals are generally most easily intercalated due to their light mass, high charge/volume ratio and in many cases strong reducing properties. An evolving area of materials chemistry, however, is to capture metals selectively, which is of technological and environmental significance but rather unexplored. Here we show that the layered telluride T2PTe2 (T=Ti, Zr) displays exclusive insertion of transition metals (for example, Cd, Zn) as opposed to alkali cations, with tetrahedral coordination preference to tellurium. Interestingly, the intercalation reactions proceed in solid state and at surprisingly low temperatures (for example, 80 °C for cadmium in Ti2PTe2). The current method of controlling selectivity provides opportunities in the search for new materials for various applications that used to be possible only in a liquid. PMID:27966540

  15. Innovative Strategy For Long Term Monitoring Of Metal And Radionuclide Plumes

    International Nuclear Information System (INIS)

    Eddy-Dilek, Carol; Millings, Margaret R.; Looney, Brian B.; Denham, Miles E.

    2014-01-01

    Many government and private industry sites that were once contaminated with radioactive and chemical wastes cannot be cleaned up enough to permit unrestricted human access. The sites will require long term management, in some cases indefinitely, leaving site owners with the challenge of protecting human health and environmental quality at these 'legacy' sites. Long-term monitoring of groundwater contamination is one of the largest projected costs in the life cycle of environmental management at the Savannah River Site, the larger DOE complex, and many large federal and private sites. There is a need to optimize the performance and manage the cost of long term surveillance and monitoring at their sites. Currently, SRNL is initiating a pilot field test using alternative protocols for long term monitoring of metals and radionuclides. A key component of the approach is that monitoring efforts are focused on measurement of low cost metrics related to hydrologic and chemical conditions that control contaminant migration. The strategy combines careful monitoring of hydrologic boundary conditions with measurement of master variables such as chemical surrogates along with a smaller number of standard well analyses. In plumes contaminated with metals, master variables control the chemistry of the groundwater system, and include redox variables (ORP, DO, chemicals), pH, specific conductivity, biological community (breakdown/decay products), and temperature. Significant changes in these variables will result in conditions whereby the plume may not be stable and therefore can be used to predict possible plume migration. Conversely, concentration measurements for all types of contaminants in groundwater are a lagging indicator plume movement - major changes contaminant concentrations indicate that contamination has migrated. An approach based on measurement of master variables and explicit monitoring of hydrologic boundary conditions combined with traditional metrics should lead

  16. Innovative Strategy For Long Term Monitoring Of Metal And Radionuclide Plumes

    Energy Technology Data Exchange (ETDEWEB)

    Eddy-Dilek, Carol; Millings, Margaret R.; Looney, Brian B.; Denham, Miles E.

    2014-01-08

    Many government and private industry sites that were once contaminated with radioactive and chemical wastes cannot be cleaned up enough to permit unrestricted human access. The sites will require long term management, in some cases indefinitely, leaving site owners with the challenge of protecting human health and environmental quality at these "legacy" sites. Long-term monitoring of groundwater contamination is one of the largest projected costs in the life cycle of environmental management at the Savannah River Site, the larger DOE complex, and many large federal and private sites. There is a need to optimize the performance and manage the cost of long term surveillance and monitoring at their sites. Currently, SRNL is initiating a pilot field test using alternative protocols for long term monitoring of metals and radionuclides. A key component of the approach is that monitoring efforts are focused on measurement of low cost metrics related to hydrologic and chemical conditions that control contaminant migration. The strategy combines careful monitoring of hydrologic boundary conditions with measurement of master variables such as chemical surrogates along with a smaller number of standard well analyses. In plumes contaminated with metals, master variables control the chemistry of the groundwater system, and include redox variables (ORP, DO, chemicals), pH, specific conductivity, biological community (breakdown/decay products), and temperature. Significant changes in these variables will result in conditions whereby the plume may not be stable and therefore can be used to predict possible plume migration. Conversely, concentration measurements for all types of contaminants in groundwater are a lagging indicator plume movement - major changes contaminant concentrations indicate that contamination has migrated. An approach based on measurement of master variables and explicit monitoring of hydrologic boundary conditions combined with traditional metrics should lead

  17. Grain-boundary migration in metals fatigued at high temperatures

    International Nuclear Information System (INIS)

    Snowden, K.U.; Stathers, P.A.; Hughes, D.S.

    1976-01-01

    It is stated that grain boundary migration in polycrystalline metals fatigued at high temperatures has been reported for FCC, BCC, and CPH metals. The migration results in a 'diamond' or orthogonal configuration of boundaries with segments aligned in the maximum sheer stress directions. It has been suggested that this migration contributes to grain boundary failure by the absorption of point defects at migrating boundaries and/or by the development of the 'diamond' configuration, which puts the boundaries in a favourable arrangement for sliding. There seems, however, to be little qualitative information on grain boundary migration under these conditions. The results are here reported of studies on grain boundary migration in Al, Cu, Zr and Zircaloy-2 specimens fatigued at temperatures where grain boundary cavitation occurs. These results indicate that during the initial 10% of the fatigue life the rate of boundary migration decreases with time and the amount of migration varies with tsup(2/3). The possible influence of boundary migration on cavitation is suggested to be limited to the initial part of the fatigue life. Mechanisms are discussed. (U.K.)

  18. Influence of temperature and salinity on heavy metal uptake by submersed plants

    Energy Technology Data Exchange (ETDEWEB)

    Fritioff, A. [Department of Botany, Stockholm University, S-106 91 Stockholm (Sweden)]. E-mail: fritioff@botan.su.se; Kautsky, L. [Department of Botany, Stockholm University, S-106 91 Stockholm (Sweden); Greger, M. [Department of Botany, Stockholm University, S-106 91 Stockholm (Sweden)

    2005-01-01

    Submersed plants can be useful in reducing heavy metal concentrations in stormwater, since they can accumulate large amounts of heavy metals in their shoots. To investigate the effects of water temperature and salinity on the metal uptake of two submersed plant species, Elodea canadensis (Michx.) and Potamogeton natans (L.), these plants were grown in the presence of Cu, Zn, Cd, and Pb at 5, 11, and 20 deg. C in combination with salinities of 0, 0.5, and 5%o. The metal concentrations in the plant tissue increased with increasing temperature in both species; the exception was the concentration of Pb in Elodea, which increased with decreasing salinity. Metal concentrations at high temperature or low salinity were up to twice those found at low temperature or high salinity. Plant biomass affected the metal uptake, with low biomass plants having higher metal concentrations than did high biomass plants. - Metal concentrations increase with increasing temperature and decreasing salinity in two aquatic plants.

  19. Influence of temperature and salinity on heavy metal uptake by submersed plants

    International Nuclear Information System (INIS)

    Fritioff, A.; Kautsky, L.; Greger, M.

    2005-01-01

    Submersed plants can be useful in reducing heavy metal concentrations in stormwater, since they can accumulate large amounts of heavy metals in their shoots. To investigate the effects of water temperature and salinity on the metal uptake of two submersed plant species, Elodea canadensis (Michx.) and Potamogeton natans (L.), these plants were grown in the presence of Cu, Zn, Cd, and Pb at 5, 11, and 20 deg. C in combination with salinities of 0, 0.5, and 5%o. The metal concentrations in the plant tissue increased with increasing temperature in both species; the exception was the concentration of Pb in Elodea, which increased with decreasing salinity. Metal concentrations at high temperature or low salinity were up to twice those found at low temperature or high salinity. Plant biomass affected the metal uptake, with low biomass plants having higher metal concentrations than did high biomass plants. - Metal concentrations increase with increasing temperature and decreasing salinity in two aquatic plants

  20. An analysis of spatial representativeness of air temperature monitoring stations

    Science.gov (United States)

    Liu, Suhua; Su, Hongbo; Tian, Jing; Wang, Weizhen

    2018-05-01

    Surface air temperature is an essential variable for monitoring the atmosphere, and it is generally acquired at meteorological stations that can provide information about only a small area within an r m radius ( r-neighborhood) of the station, which is called the representable radius. In studies on a local scale, ground-based observations of surface air temperatures obtained from scattered stations are usually interpolated using a variety of methods without ascertaining their effectiveness. Thus, it is necessary to evaluate the spatial representativeness of ground-based observations of surface air temperature before conducting studies on a local scale. The present study used remote sensing data to estimate the spatial distribution of surface air temperature using the advection-energy balance for air temperature (ADEBAT) model. Two target stations in the study area were selected to conduct an analysis of spatial representativeness. The results showed that one station (AWS 7) had a representable radius of about 400 m with a possible error of less than 1 K, while the other station (AWS 16) had the radius of about 250 m. The representable radius was large when the heterogeneity of land cover around the station was small.

  1. Towards a monitoring system of temperature extremes in Europe

    Science.gov (United States)

    Lavaysse, Christophe; Cammalleri, Carmelo; Dosio, Alessandro; van der Schrier, Gerard; Toreti, Andrea; Vogt, Jürgen

    2018-01-01

    Extreme-temperature anomalies such as heat and cold waves may have strong impacts on human activities and health. The heat waves in western Europe in 2003 and in Russia in 2010, or the cold wave in southeastern Europe in 2012, generated a considerable amount of economic loss and resulted in the death of several thousands of people. Providing an operational system to monitor extreme-temperature anomalies in Europe is thus of prime importance to help decision makers and emergency services to be responsive to an unfolding extreme event. In this study, the development and the validation of a monitoring system of extreme-temperature anomalies are presented. The first part of the study describes the methodology based on the persistence of events exceeding a percentile threshold. The method is applied to three different observational datasets, in order to assess the robustness and highlight uncertainties in the observations. The climatology of extreme events from the last 21 years is then analysed to highlight the spatial and temporal variability of the hazard, and discrepancies amongst the observational datasets are discussed. In the last part of the study, the products derived from this study are presented and discussed with respect to previous studies. The results highlight the accuracy of the developed index and the statistical robustness of the distribution used to calculate the return periods.

  2. Elevated Temperature Sensors for On-Line Critical Equipment Health Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    James Sebastian

    2006-03-31

    The objective of the program was to improve high temperature piezoelectric aluminum nitride (AlN) sensor technology to make it useful for instrumentation and health monitoring of current and future electrical power generation equipment. Improvements were aimed primarily at extending the useful temperature range of the sensor from approximately 700 C to above 1000 C, and investigating ultrasonic coupling to objects at these temperatures and tailoring high temperature coupling for use with the sensor. During the project, the chemical vapor deposition (CVD) AlN deposition process was successfully transferred from film production on tungsten carbide substrates to titanium alloy and silicon carbide (SiC) substrates. Film adhesion under thermal cycling was found to be poor, and additional substrate materials and surface preparations were evaluated. A new, porous SiC substrate improved the performance but not to the point of making the films useful for sensors. Near the end of the program, a new family of high temperature piezoelectric materials came to the attention of the program. Samples of langasite, the most promising member of this family, were obtained and experimental data showed promise for use up to the 1000 C target temperature. In parallel, research successfully determined that metal foil under moderate pressure provided a practical method of coupling ultrasound at high temperature. A conceptual sensor was designed based upon these methods and was tested in the laboratory.

  3. Application of displacement monitoring system on high temperature steam pipe

    Science.gov (United States)

    Ghaffar, M. H. A.; Husin, S.; Baek, J. E.

    2017-10-01

    High-energy piping systems of power plants such as Main Steam (MS) pipe or Hot Reheat (HR) pipe are operating at high temperature and high pressure at base and cyclic loads. In the event of transient condition, a pipe can be deflected dramatically and caused high stress in the pipe, yielding to failure of the piping system. Periodic monitoring and walk down can identify abnormalities but limitations exist in the standard walk down practice. This paper provides a study of pipe displacement monitoring on MS pipe of coal-fired power plant to continuously capture the pipe movement behaviour at different load using 3-Dimensional Displacement Measuring System (3DDMS). The displacement trending at Location 5 and 6 (north and south) demonstrated pipes displace less than 25% to that of design movement. It was determined from synchronisation analysis that Location 7 (north) and Location 8 (south) pipe actual movement difference has exceeded the design movement difference. Visual survey at specified locations with significant displacement trending reveals issues of hydraulic snubber and piping interferences. The study demonstrated that the displacement monitoring is able to capture pipe movement at all time and allows engineer to monitor pipe movement behaviour, aids in identifying issue early for remedy action.

  4. Dynamics of a metal overlayer on metallic substrates: High temperature effects

    International Nuclear Information System (INIS)

    Rahman, T.S.; Black, J.E.; Tian, Zeng Ju

    1992-01-01

    We have explored the structure and the dynamics of a bimetallic system consisting of a hexagonal (almost) overlayer of Ag on a square lattice (Ni(100) and Cu(100)), as a function of the surface temperature. In each case the structure is ''nearly'' incommensurate giving rise to a low frequency Goldstone mode. Also, the overlayer atoms slosh back and forth over the substrate in a corrugated fashion. The calculated dispersion of the Ag/metal vertical mode, at room temperature, is in excellent agreement with experimental data. At higher temperatures floater atoms appear on top of the overlayer displaying a variety of cluster formations and also exchanges with the substrate atoms leading to surface disordering, interdiffusion and melting

  5. Evaluation of complexing agents and column temperature in ion chromatographic separation of alkali metals, alkaline earth metals and transition metals ion

    International Nuclear Information System (INIS)

    Kelkar, Anoop; Pandey, Ashish; Name, Anil B.; Das, D.K.; Behere, P.G.; Mohd Afzal

    2015-01-01

    The aim of ion chromatography method development is the resolution of all metal ions of interests. Resolution can be improved by changing the selectivity. Selectivity in chromatography can be altered by changes in mobile phase (eg eluent type, eluent strength) or through changes in stationary phase. Temperature has been used in altering the selectivity of particularly in reversed phase liquid chromatography and ion exchange chromatography. Present paper describe the retention behaviour of alkali metals, alkaline earth metals and transition metal ions on a silica based carboxylate function group containing analyte column. Alkali metals, alkaline earth metals and transition metal ions were detected by ion conductivity and UV-VIS detectors respectively

  6. Control for monitoring thickness of high temperature refractory

    Science.gov (United States)

    Caines, M.J.

    1982-11-23

    This invention teaches an improved monitoring device for detecting the changes in thickness of high-temperature refractory, the device consists of a probe having at least two electrically conductive generally parallel elements separated by a dielectric material. The probe is implanted or embedded directly in the refractory and is elongated to extend in line with the refractory thickness to be measured. Electrical inputs to the conductive elements provide that either or both the electrical conductance or capacitance can be found, so that charges over lapsed time periods can be compared in order to detect changes in the thickness of the refractory.

  7. Ferromagnetism and temperature-dependent electronic structure in metallic films

    International Nuclear Information System (INIS)

    Herrmann, T.

    1999-01-01

    -, layer-, and temperature-dependent. The last part of this work is concerned about the temperature-driven reorientation transition in thin metallic films. For the description of the magnetic anisotropy in thin films the dipole interaction as well as the spin-orbit interaction have to be included in the model. By calculating the temperature-dependence of the magnetic anisotropy energy it is found that both types of temperature-driven reorientation transitions, from out-of-plane to in-plane (''Fe-type'') and from in-plane to out-of-plane(''Ni-type'') magnetization are possible within the generalized Hubbard films

  8. Creep testing of foil-gage metals at elevated temperature using an automated data acquisition system

    Science.gov (United States)

    Blackburn, L. B.

    1983-01-01

    A method is being developed to obtain creep data on foil gage metals at elevated temperatures using an automated data acquisition system in conjunction with a mechanically counter balanced extensometer. The automated system components include the Hewlett-Packard (HP) 9845A desktop computer, the HP 3455A digital voltmeter and the HP 3495A scanner. Software for test monitoring and data collection was developed; data manipulation, including curve plotting was done with a HP regression analysis software package. Initial creep tests were conducted on .003 in. thick foil specimens of Ti-6A1-4V at temperatures of 800 F and 1000 F and at stress levels of 25 ksi and 45 ksi. For comparison, duplicate tests were run on .049 in. thick specimens sheet of the same alloy. During testing, the furnace and specimen temperature, bridge voltage, strain and load output were automatically monitored and recorded at predetermined intervals. Using the HP regression analysis program, recorded strain output was plotted as a function of time. These resultant creep curves indicate that, under similar conditions of temperature and stress, foil gage specimens exhibit a higher creep rate than sheet specimens.

  9. Status of design code work for metallic high temperature components

    International Nuclear Information System (INIS)

    Bieniussa, K.; Seehafer, H.J.; Over, H.H.; Hughes, P.

    1984-01-01

    The mechanical components of high temperature gas-cooled reactors, HTGR, are exposed to temperatures up to about 1000 deg. C and this in a more or less corrosive gas environment. Under these conditions metallic structural materials show a time-dependent structural behavior. Furthermore changes in the structure of the material and loss of material in the surface can result. The structural material of the components will be stressed originating from load-controlled quantities, for example pressure or dead weight, and/or deformation-controlled quantities, for example thermal expansion or temperature distribution, and thus it can suffer rowing permanent strains and deformations and an exhaustion of the material (damage) both followed by failure. To avoid a failure of the components the design requires the consideration of the following structural failure modes: ductile rupture due to short-term loadings; creep rupture due to long-term loadings; reep-fatigue failure due to cyclic loadings excessive strains due to incremental deformation or creep ratcheting; loss of function due to excessive deformations; loss of stability due to short-term loadings; loss of stability due to long-term loadings; environmentally caused material failure (excessive corrosion); fast fracture due to instable crack growth

  10. Coaxial monitoring of temperature field in selective pulsed laser melting

    Science.gov (United States)

    Liu, Che; Chen, Zhongyun; Cao, Hongzhong; Zhou, Jianhong

    2017-10-01

    Selective Laser Melting is a rapid manufacturing technology which produces complex parts layer by layer. The presence of thermal stress and thermal strain in the forming process often leads to defects in the formed parts. In order to detect fabricate errors and avoid failure which caused by thermal gradient in time. An infrared thermal imager and a high speed CCD camera were applied to build a coaxial optical system for real-time monitoring the temperature distribution and changing trend of laser affected zone in SLM forming process. Molten tracks were fabricated by SLM under different laser parameters such as frequency, pulse width. And the relationship between the laser parameters and the temperature distribution were all obtained and analyzed.

  11. Vaporization of tungsten-metal in steam at high temperatures

    International Nuclear Information System (INIS)

    Greene, G.A.; Finfrock, C.C.

    2000-01-01

    The vaporization of tungsten from the APT spallation target dominates the radiological source term for unmitigated target overheating accidents. Chemical reactions of tungsten with steam which persist to tungsten temperatures as low as 800 C result in the formation of a hydrated tungsten-oxide which has a high vapor pressure and is readily convected in a flowing atmosphere. This low-temperature vaporization reaction essentially removes the oxide film that forms on the tungsten-metal surface as soon as it forms, leaving behind a fresh metallic surface for continued oxidation and vaporization. Experiments were conducted to measure the oxidative vaporization rates of tungsten in steam as part of the effort to quantify the MT radiological source term for severe target accidents. Tests were conducted with tungsten rods (1/8 inch diameter, six inches long) heated to temperatures from approximately 700 C to 1350 C in flowing steam which was superheated to 140 C. A total of 19 experiments was conducted. Fifteen tests were conducted by RF induction heating of single tungsten rods held vertical in a quartz glass retort. Four tests were conducted in a vertically-mounted tube furnace for the low temperature range of the test series. The aerosol which was generated and transported downstream from the tungsten rods was collected by passing the discharged steam through a condenser. This procedure insured total collection of the steam along with the aerosol from the vaporization of the rods. The results of these experiments revealed a threshold temperature for tungsten vaporization in steam. For the two tests at the lowest temperatures which were tested, approximately 700 C, the tungsten rods were observed to oxidize without vaporization. The remainder of the tests was conducted over the temperature range of 800 C to 1350 C. In these tests, the rods were found to have lost weight due to vaporization of the tungsten and the missing weight was collected in the downstream condensate

  12. A Wireless Portable High Temperature Data Monitor for Tunnel Ovens

    Directory of Open Access Journals (Sweden)

    Ricardo Mayo Bayón

    2014-08-01

    Full Text Available Tunnel ovens are widely used in the food industry to produce biscuits and pastries. In order to obtain a high quality product, it is very important to control the heat transferred to each piece of dough during baking. This paper proposes an innovative, non-distorting, low cost wireless temperature measurement system, called “eBiscuit”, which, due to its size, format and location in the metal rack conveyor belt in the oven, is able to measure the temperature a real biscuit experience while baking. The temperature conditions inside the oven are over 200 °C for several minutes, which could damage the “eBiscuit” electronics. This paper compares several thermal insulating materials that can be used in order to avoid exceeding the maximum operational conditions (80 °C in the interior of the “eBiscuit. The data registered is then transmitted to a base station where information can be processed to obtain an oven model. The experimental results with real tunnel ovens confirm its good performance, which allows detecting production anomalies early on.

  13. A wireless portable high temperature data monitor for tunnel ovens.

    Science.gov (United States)

    Mayo Bayón, Ricardo; González Suárez, Víctor M; Mateos Martín, Felipe; Lopera Ronda, Juan M; Álvarez Antón, Juan C

    2014-08-12

    Tunnel ovens are widely used in the food industry to produce biscuits and pastries. In order to obtain a high quality product, it is very important to control the heat transferred to each piece of dough during baking. This paper proposes an innovative, non-distorting, low cost wireless temperature measurement system, called "eBiscuit", which, due to its size, format and location in the metal rack conveyor belt in the oven, is able to measure the temperature a real biscuit experience while baking. The temperature conditions inside the oven are over 200 °C for several minutes, which could damage the "eBiscuit" electronics. This paper compares several thermal insulating materials that can be used in order to avoid exceeding the maximum operational conditions (80 °C) in the interior of the "eBiscuit. The data registered is then transmitted to a base station where information can be processed to obtain an oven model. The experimental results with real tunnel ovens confirm its good performance, which allows detecting production anomalies early on.

  14. Design of Heavy Metals Monitoring System in Water Based on WSN and GPRS

    Directory of Open Access Journals (Sweden)

    Ke Lin

    2014-04-01

    Full Text Available In order to realize the real-time monitoring of heavy metals in water environment, a new type of heavy metal monitoring system was developed. The system was composed of monitoring terminal, gateway, GPRS network and upper computer monitoring center. The system detected the heavy metal ion concentrations by ion-selective electrode array and came into the system error automatic compensation method in the detection process. The collecting data was transported to the monitoring center through the cooperation between the wireless sensor network constituted by CC2530 and General Packet Radio Service network. The test result shows that the system can increased precision dramatically and strengthens the real-time transmission capacity effectively. The system is reliable in transmission, high real-time performance, flexible in networking and can be applied to continuous remote monitoring of heavy metals pollution.

  15. Metal Phosphates as Intermediate Temperature Proton Conducting Electrolytes

    DEFF Research Database (Denmark)

    Huang, Yunjie; Li, Q.F.; Pan, Chao

    2012-01-01

    A series of metal phosphates were synthesized and screened as potential proton conductor electrolytes for fuel cells and electrolysers operational at intermediate temperatures. Among the selected, niobium and bismuth phosphates exhibited a proton conductivity of 10-2 and 10-7 S cm-1, respectively......, under the anhydrous atmosphere at 250 °C, showing close correlation with the presence of hydroxyl groups in the phosphate phases. At the water partial pressure of above 0.6 atm, both phosphates possessed a proton conductivity to a level of above 3 x 10-2 S cm-1. Reasonable stability of the proton...... conductivity was observed under either a constant low water partial pressure or under a humidity cycling test within a period of more than 80 hours....

  16. High temperature seal for joining ceramics and metal alloys

    Science.gov (United States)

    Maiya, P. Subraya; Picciolo, John J.; Emerson, James E.; Dusek, Joseph T.; Balachandran, Uthamalingam

    1998-01-01

    For a combination of a membrane of SrFeCo.sub.0.5 O.sub.x and an Inconel alloy, a high-temperature seal is formed between the membrane and the alloy. The seal is interposed between the alloy and the membrane, and is a fritted compound of Sr oxide and boric oxide and a fritted compound of Sr, Fe and Co oxides. The fritted compound of SrFeCo.sub.0.50 O.sub.x is present in the range of from about 30 to 70 percent by weight of the total sealant material and the fritted compound of Sr oxide and boric oxide has a mole ratio of 2 moles of the Sr oxide for each mole of boric oxide. A method of sealing a ceramic to an Inconel metal alloy is also disclosed.

  17. Temperature Variations within Wooden and Metal Grain Silos in the Tropics during Storage of Maize (Zea Mays

    Directory of Open Access Journals (Sweden)

    B. A. ALABADAN

    2005-01-01

    Full Text Available The study was carried out on the comparative analysis of temperature variation within wooden and metal grain silos under a typical tropical weather condition in Nigeria. Temperature variations within and outside the silos were monitored for 130days (July to November during storage of maize. Results showed that the grain temperature at the centre of the silos ranged between 24.0-32.7°C and 23.8-35.0°C for wooden and metal silos respectively. Also, at the silo walls, grain temperatures ranged between 24.5-35.8°C and 24.0-34.7°C respectively. The standard error of estimate between the results of the silos at the centres and walls were 1.65°C and 1.16°C respectively. The temperatures at the top of the metal silo (grain surface were 1.9°C and 4.1°C higher than those of the wooden silo and ambient respectively. It can be concluded that wooden silo is more effective at temperature control than metal silo under the tropical conditions.

  18. Temperature-monitored optical treatment for radial tissue expansion.

    Science.gov (United States)

    Bak, Jinoh; Kang, Hyun Wook

    2017-07-01

    Esophageal stricture occurs in 7-23% of patients with gastroesophageal reflux disease. However, the current treatments including stent therapy, balloon dilation, and bougienage involve limitations such as stent migration, formation of the new strictures, and snowplow effect. The purpose of the current study was to investigate the feasibility of structural expansion in tubular tissue ex vivo during temperature-monitored photothermal treatment with a diffusing applicator for esophageal stricture. Porcine liver was used as an ex vivo tissue sample for the current study. A glass tube was used to maintain a constant distance between the diffuser and tissue surface and to evaluate any variations in the luminal area after 10-W 1470-nm laser irradiation for potential stricture treatment. The 3D goniometer measurements confirmed roughly isotropic distribution with less than 10% deviation from the average angular intensity over 2π (i.e., 0.86 ± 0.09 in arbitrary unit) from the diffusing applicator. The 30-s irradiation increased the tissue temperature up to 72.5 °C, but due to temperature feedback, the interstitial tissue temperature became saturated at 70 °C (i.e., steady-state error = ±0.4 °C). The irradiation times longer than 5 s presented area expansion index of 1.00 ± 0.04, signifying that irreversible tissue denaturation permanently deformed the lumen in a circular shape and secured the equivalent luminal area to that of the glass tube. Application of a temperature feedback controller for photothermal treatment with the diffusing applicator can regulate the degree of thermal denaturation to feasibly treat esophageal stricture in a tubular tissue.

  19. Sensor programming and concept implementation of a temperature monitoring system, using Arduino as prototyping platform

    DEFF Research Database (Denmark)

    Sbîrnă, Sebastian; Søberg, Peder Veng; Sbîrnă, Liana Simona

    2016-01-01

    The present work reports the programming paradigms that have been developed for a temperature monitoring system able to provide accurate data regarding food temperatures inside refrigerated vehicles and alert the driver accordingly, in relation to which temperature states are encountered. The men......The present work reports the programming paradigms that have been developed for a temperature monitoring system able to provide accurate data regarding food temperatures inside refrigerated vehicles and alert the driver accordingly, in relation to which temperature states are encountered...

  20. Ultrasonic Approach to Nonivasive Temperature Monitoring During Microwave Thermotherapy

    Directory of Open Access Journals (Sweden)

    J. Vrba

    2001-06-01

    Full Text Available Microwave thermotherapy (MT is an oncological treatment. At presentthe invasive thermometer probes are clinically used for temperaturemeasuring during an MT. Any invasive handling of tumors is ofhigh-risk. A new possible method of noninvasive monitoring oftemperature distribution in tissue has been developed. An MT treatmentof the experimentally induced pedicle-tumors of the rat was prepared.For 100 rat samples a strong correlation between the mean gray level inthe ROIs in the ultrasound pictures and the invasively measuredtemperature in the range 37-44 °C was found. The correlationcoefficient of the mean gray level and the invasively measuredtemperature is 0.96a0.05. A system for representation of changes ofspatial temperature distribution of the whole tumor during MT ispresented.

  1. Phonon effect on the temperature dependence of spin susceptibility and magnetization in metals

    Energy Technology Data Exchange (ETDEWEB)

    Kim, D.J.; Tanaka, C.; Ukon, S.

    1985-06-01

    In many transition metals the paramagnetic spin susceptibility X increases with increasing temperature much beyond ordinary theories could account for. We demonstrate how the effect of the electron-phonon interactions enable us to understand such temperature dependence of X.

  2. Hybrid Metal/Electrolyte Monolithic Low Temperature SOFCs

    National Research Council Canada - National Science Library

    Cochran, Joe

    2004-01-01

    The program objective is to develop SOFCs, operating in the 500-700 degrees C range, based on Metal/Electrolyte square cell honeycomb formed by simultaneous powder extrusion of electrolyte and metal...

  3. High Performance High Temperature Thermoelectric Composites with Metallic Inclusions

    Science.gov (United States)

    Ma, James M. (Inventor); Bux, Sabah K. (Inventor); Fleurial, Jean-Pierre (Inventor); Ravi, Vilupanur A. (Inventor); Firdosy, Samad A. (Inventor); Star, Kurt (Inventor); Kaner, Richard B. (Inventor)

    2017-01-01

    The present invention provides a composite thermoelectric material. The composite thermoelectric material can include a semiconductor material comprising a rare earth metal. The atomic percent of the rare earth metal in the semiconductor material can be at least about 20%. The composite thermoelectric material can further include a metal forming metallic inclusions distributed throughout the semiconductor material. The present invention also provides a method of forming this composite thermoelectric material.

  4. The Influence of Logger Bias on Reported Temperature Trends: Implications for Temperature Monitoring Networks

    Science.gov (United States)

    Malcolm, I.; Fryer, R. J.; Bacon, P. J.; Stirling, D.

    2015-12-01

    There has been increasing interest in river temperature monitoring and research in recent years. This has been driven by factors including a greater awareness of the importance of river temperature for freshwater ecology, the potential for detrimental extremes under climate change and the availability of increasingly affordable dataloggers. A number of studies have attempted to collate and analyse pre-existing long-term (decadal) datasets to assess for evidence of temporal trends. These studies require considerable care given the magnitude of temporal trends (often 25 years. The bias of temperature measurements made by different dataloggers (two makes and five models) was determined through cross-calibration against a reference datalogger. Long-term trends in stream temperature metrics (daily mean, max, min) were characterised using Generalised Additive Mixed Models (GAMM). Models were fitted to (1) the raw data and (2) data corrected for logger bias. Significant non-linear temporal trends were observed in the raw data. These trends were accentuated when corrected for logger bias. Given the potential to accentuate or remove long-term trends, it is suggested that robust internal and external calibration and quality control procedures should be established for new temperature networks. Such approaches are capable of removing logger bias and improving accuracy by an order of magnitude over manufacturer stated values.

  5. High temperature metallic materials for gas-cooled reactors

    International Nuclear Information System (INIS)

    1989-06-01

    The Specialists' Meeting was organized in conjunction with an earlier meeting on this topic held in Vienna, Austria, 1981, which provided for a comprehensive review of the status of materials development and testing at that time and for a description of test facilities. This meeting provided an opportunity (1) to review and discuss the progress made since 1981 in the development, testing and qualification of high temperature metallic materials, (2) to critically assess results achieved, and (3) to give directions for future research and development programmes. In particular, the meeting provided a form for a close interaction between component designers and materials specialists. The meeting was attended by 48 participants from France, People's Republic of China, Federal Republic of Germany, Japan, Poland, Switzerland, United Kingdom, USSR and USA presenting 22 papers. The technical part of the meeting was subdivided into four technical sessions: Components Design and Testing - Implications for Materials (4 papers); Microstructure and Environmental Compatibility (4 papers); Mechanical Properties (9 papers); New Alloys and Developments (6 papers). At the end of the meeting a round table discussion was organized in order to summarize the meeting and to make recommendations for future activities. This volume contains all papers presented at the meeting. A separate abstract was prepared for each of these papers. Refs, figs and tabs

  6. Screening of seaweeds in the East China Sea as potential bio-monitors of heavy metals.

    Science.gov (United States)

    Pan, Yaoru; Wernberg, Thomas; de Bettignies, Thibaut; Holmer, Marianne; Li, Ke; Wu, Jiaping; Lin, Fang; Yu, Yan; Xu, Jiang; Zhou, Chaosheng; Huang, Zhixing; Xiao, Xi

    2018-03-30

    Seaweeds are good bio-monitors of heavy metal pollution and have been included in European coastal monitoring programs. However, data for seaweed species in China are scarce or missing. In this study, we explored the potential of seaweeds as bio-monitor by screening the natural occurring seaweeds in the "Kingdom of seaweed and shellfish" at Dongtou Islands, the East China Sea. Totally, 12 seaweed species were collected from six sites, with richness following the sequence of Rhodophyta > Phaeophyta > Chlorophyta. The concentration of heavy metals (Cu, Cr, Ni, Zn, Pb, Cd, As) in the seaweeds was determined, and the bioaccumulation coefficient was calculated. A combination of four seaweeds, Pachydictyon coriaceum, Gelidium divaricatum, Sargassum thunbergii, and Pterocladiella capillacea, were proposed as bio-monitors due to their high bioaccumulation capabilities of specific heavy metals in the East China Sea and hence hinted the importance of using seaweed community for monitoring of pollution rather than single species. Our results provide first-hand data for the selection of bio-monitor species for heavy metals in the East China Sea and contribute to selection of cosmopolitan bio-monitor communities over geographical large area, which will benefit the establishment of monitoring programs for coastal heavy metal contamination.

  7. Preparation of 147Pm metal and the determination of the melting point and phase transformation temperatures

    International Nuclear Information System (INIS)

    Angelini, P.; Adair, H.L.

    1976-07-01

    The promethium metal used in the determination of the melting point and phase transformation temperatures was prepared by reduction of promethium oxide with thorium metal at 1600 0 C and distilling the promethium metal into a quartz dome. The melting point and phase transformation temperatures of promethium metal were found to be 1042 +- 5 0 C and 890 +- 5 0 C, respectively. The ratio for the heat of the high-temperature transformation to the heat of fusion was determined to be 0.415

  8. A high-temperature shape memory alloy sensor for combustion monitoring and control

    Science.gov (United States)

    Shaw, Greg S.; Snyder, Joseph T.; Prince, Troy S.; Willett, Michael C.

    2005-05-01

    Innovations in the use of thin film SMA materials have enabled the development of a harsh environment pressure sensor useful for combustion monitoring and control. Development of such active combustion control has been driven by rising fuel costs and environmental pressures. Active combustion control, whether in diesel, spark ignited or turbine engines requires feedback to the engine control system in order to adjust the quantity, timing, and placement of fuel charges. To be fully effective, sensors must be integrated into each engine in a manner that will allow continuous combustion monitoring (turbine engines) or monitoring of each discrete combustion event (diesel and SI engines). To date, the sensors available for detection of combustion events and processes have suffered from one or more of three problems: 1) Low sensitivity: The sensors are unable to provide and adequate signal-to-noise ratio in the high temperature and electrically noisy environment of the engine compartment. Attempts to overcome this difficulty have focused on heat removal and/or temperature compensation or more challenging high temperature electronics. 2) Low reliability: Sensors and/or sensor packages have been unable to withstand the engine environment for extended periods of time. Issues have included gross degradation and more subtle issues such as migration of dopants in semiconductor sensor materials. 3) High cost: The materials that have been used, the package concepts employed, and the required support electronics have all contributed to the high cost of the few sensor systems available. Prices have remained high due to the limited demand associated with the poor reliability and the high price itself. Ternary titanium nickel alloys, with platinum group metal substitution for the nickel, are deposited as thin films on MEMS-based diaphragms and patterned to form strain gages of a standard metal film configuration. The strain induced phase transformation of the SMA is used as a

  9. Temperature-modulated graphene oxide resistive humidity sensor for indoor air quality monitoring

    Science.gov (United States)

    de Luca, A.; Santra, S.; Ghosh, R.; Ali, S. Z.; Gardner, J. W.; Guha, P. K.; Udrea, F.

    2016-02-01

    In this paper we present a temperature-modulated graphene oxide (GO) resistive humidity sensor that employs complementary-metal-oxide-semiconductor (CMOS) micro-electro-mechanical-system (MEMS) micro-hotplate technology for the monitoring and control of indoor air quality (IAQ). GO powder is obtained by chemical exfoliation, dispersed in water and deposited via ink-jet printing onto a low power micro-hotplate. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) show the typical layered and wrinkled morphology of the GO. Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Fourier transform infra-red (FTIR) spectroscopy indicate that the GO flakes possess a significant number of oxygen containing functional groups (epoxy, carbonyl, hydroxyl) extremely attractive for humidity detection. Electro-thermal characterisation of the micro-hotplates shows a thermal efficiency of 0.11 mW per °C, resulting in a sensor DC power consumption of only 2.75 mW at 50 °C. When operated in an isothermal mode, the sensor response is detrimentally affected by significant drift, hysteretic behaviour, slow response/recovery times and hence poor RH level discrimination. Conversely, a temperature modulation technique coupled with a differential readout methodology results in a significant reduction of the sensor drift, improved linear response with a sensitivity of 0.14 mV per %, resolution below 5%, and a maximum hysteresis of +/-5% response and recovery times equal to 189 +/- 49 s and 89 +/- 5 s, respectively. These performance parameters satisfy current IAQ monitoring requirements. We have thus demonstrated the effectiveness of integrating GO on a micro-hotplate CMOS-compatible platform enabling temperature modulation schemes to be easily applied in order to achieve compact, low power, low cost humidity IAQ monitoring.In this paper we present a temperature-modulated graphene oxide (GO) resistive humidity sensor that employs complementary-metal

  10. Dislocation and Structural Studies at Metal-Metallic Glass Interface at Low Temperature

    Science.gov (United States)

    Gupta, Pradeep; Yedla, Natraj

    2017-12-01

    In this paper, molecular dynamics (MD) simulation deformation studies on the Al (metal)-Cu50Zr50 (metallic glass) model interface is carried out based on cohesive zone model. The interface is subjected to mode-I loading at a strain rate of 109 s-1 and temperature of 100 K. The dislocations reactions and evolution of dislocation densities during the deformation have been investigated. Atomic interactions between Al, Cu and Zr atoms are modeled using EAM (embedded atom method) potential, and a timestep of 0.002 ps is used for performing the MD simulations. A circular crack and rectangular notch are introduced at the interface to investigate the effect on the deformation behavior and fracture. Further, scale size effect is also investigated. The structural changes and evolution of dislocation density are also examined. It is found that the dominant deformation mechanism is by Shockley partial dislocation nucleation. Amorphization is observed in the Al regions close to the interface and occurs at a lower strain in the presence of a crack. The total dislocation density is found to be maximum after the first yield in both the perfect and defect interface models and is highest in the case of perfect interface with a density of 6.31 × 1017 m-2. In the perfect and circular crack defect interface models, it is observed that the fraction of Shockley partial dislocation density decreases, whereas that of strain rod dislocations increases with increase in strain.

  11. The Rover Environmental Monitoring Station Ground Temperature Sensor: a pyrometer for measuring ground temperature on Mars.

    Science.gov (United States)

    Sebastián, Eduardo; Armiens, Carlos; Gómez-Elvira, Javier; Zorzano, María P; Martinez-Frias, Jesus; Esteban, Blanca; Ramos, Miguel

    2010-01-01

    We describe the parameters that drive the design and modeling of the Rover Environmental Monitoring Station (REMS) Ground Temperature Sensor (GTS), an instrument aboard NASA's Mars Science Laboratory, and report preliminary test results. REMS GTS is a lightweight, low-power, and low cost pyrometer for measuring the Martian surface kinematic temperature. The sensor's main feature is its innovative design, based on a simple mechanical structure with no moving parts. It includes an in-flight calibration system that permits sensor recalibration when sensor sensitivity has been degraded by deposition of dust over the optics. This paper provides the first results of a GTS engineering model working in a Martian-like, extreme environment.

  12. The Rover Environmental Monitoring Station Ground Temperature Sensor: A Pyrometer for Measuring Ground Temperature on Mars

    Directory of Open Access Journals (Sweden)

    Miguel Ramos

    2010-10-01

    Full Text Available We describe the parameters that drive the design and modeling of the Rover Environmental Monitoring Station (REMS Ground Temperature Sensor (GTS, an instrument aboard NASA’s Mars Science Laboratory, and report preliminary test results. REMS GTS is a lightweight, low-power, and low cost pyrometer for measuring the Martian surface kinematic temperature. The sensor’s main feature is its innovative design, based on a simple mechanical structure with no moving parts. It includes an in-flight calibration system that permits sensor recalibration when sensor sensitivity has been degraded by deposition of dust over the optics. This paper provides the first results of a GTS engineering model working in a Martian-like, extreme environment.

  13. The Rover Environmental Monitoring Station Ground Temperature Sensor: A Pyrometer for Measuring Ground Temperature on Mars

    Science.gov (United States)

    Sebastián, Eduardo; Armiens, Carlos; Gómez-Elvira, Javier; Zorzano, María P.; Martinez-Frias, Jesus; Esteban, Blanca; Ramos, Miguel

    2010-01-01

    We describe the parameters that drive the design and modeling of the Rover Environmental Monitoring Station (REMS) Ground Temperature Sensor (GTS), an instrument aboard NASA’s Mars Science Laboratory, and report preliminary test results. REMS GTS is a lightweight, low-power, and low cost pyrometer for measuring the Martian surface kinematic temperature. The sensor’s main feature is its innovative design, based on a simple mechanical structure with no moving parts. It includes an in-flight calibration system that permits sensor recalibration when sensor sensitivity has been degraded by deposition of dust over the optics. This paper provides the first results of a GTS engineering model working in a Martian-like, extreme environment. PMID:22163405

  14. The use of distributed temperature sensing technology for monitoring wildland fire intensity and distribution.

    Science.gov (United States)

    Ochoa, C. G.; Cram, D.; Hatch, C. E.; Tyler, S. W.

    2014-12-01

    Distributed temperature sensing (DTS) technology offers a viable alternative for accurately measuring wildland fire intensity and distribution in real time applications. We conducted an experiment to test the use of DTS as an alternative technology to monitor prescribed fire temperatures in real time and across a broad spatial scale. The custom fiber-optic cable consisted of three fiber optic lines buffered by polyamide, copper, and polyvinyl chloride, respectively, each armored in a stainless steel tube backfilled with Nitrogen gas. The 150 m long cable was deployed in three different 20 by 26 m experimental plots of short-grass rangeland in central New Mexico. Cable was arranged to maximize coverage of the experimental plots and allow cross-comparison between two main parallel straight-line sections approximately 8 m apart. A DTS system recorded fire temperatures every three seconds and integrated every one meter. A series of five thermocouples attached to a datalogger were placed at selected locations along the cable and also recorded temperature data every three seconds on each fiber. Results indicate that in general there is good agreement between thermocouple-measured and DTS-measured temperatures. A close match in temperature between DTS and thermocouples was particularly observed during the rising limb but not so much during the decline. The metal armoring of the fiber-optic cable remained hot longer than the thermocouples after the flames had passed. The relatively short-duration, high-intensity, prescribed burn fire in each plot resulted in temperatures reaching up to 450 degrees Celsius. In addition, DTS data allow for illustration of the irregular nature of flame speed and travel path across the rangeland grasses, a phenomenon that was impossible to quantify without the use of this tool. This study adds to the understanding of using DTS as a new alternative tool for better characterizing wildland fire intensity, distribution and travel patterns, and

  15. An Evaluation of Portable Wet Bulb Globe Temperature Monitor Accuracy.

    Science.gov (United States)

    Cooper, Earl; Grundstein, Andrew; Rosen, Adam; Miles, Jessica; Ko, Jupil; Curry, Patrick

    2017-12-01

      Wet bulb globe temperature (WBGT) is the gold standard for assessing environmental heat stress during physical activity. Many manufacturers of commercially available instruments fail to report WBGT accuracy.   To determine the accuracy of several commercially available WBGT monitors compared with a standardized reference device.   Observational study.   Field test.   Six commercially available WBGT devices.   Data were recorded for 3 sessions (1 in the morning and 2 in the afternoon) at 2-minute intervals for at least 2 hours. Mean absolute error (MAE), root mean square error (RMSE), mean bias error (MBE), and the Pearson correlation coefficient ( r) were calculated to determine instrument performance compared with the reference unit.   The QUESTemp° 34 (MAE = 0.24°C, RMSE = 0.44°C, MBE = -0.64%) and Extech HT30 Heat Stress Wet Bulb Globe Temperature Meter (Extech; MAE = 0.61°C, RMSE = 0.79°C, MBE = 0.44%) demonstrated the least error in relation to the reference standard, whereas the General WBGT8778 Heat Index Checker (General; MAE = 1.18°C, RMSE = 1.34°C, MBE = 4.25%) performed the poorest. The QUESTemp° 34 and Kestrel 4400 Heat Stress Tracker units provided conservative measurements that slightly overestimated the WBGT provided by the reference unit. Finally, instruments using the psychrometric wet bulb temperature (General, REED Heat Index WBGT Meter, and WBGT-103 Heat Stroke Checker) tended to underestimate the WBGT, and the resulting values more frequently fell into WBGT-based activity categories with fewer restrictions as defined by the American College of Sports Medicine.   The QUESTemp° 34, followed by the Extech, had the smallest error compared with the reference unit. Moreover, the QUESTemp° 34, Extech, and Kestrel units appeared to offer conservative yet accurate assessments of the WBGT, potentially minimizing the risk of allowing physical activity to continue in stressful heat environments. Instruments using the

  16. Monitoring metal speciation in the rivers meuse and rhine using DGT

    NARCIS (Netherlands)

    Cleven, Rob; Nur, Yusuf; Krystek, Petra; Van Den Berg, Gerard

    Although a number of metal speciation methods are nowadays available, most water quality regulations are based on total metal concentrations. One of the main reasons for the ignorance of speciation is the lack of methods with potentiality for monitoring. Conditions that have to be met by such

  17. High temperature liquid metal corrosion and high temperature electrical conductivity of Y 2O 3

    Science.gov (United States)

    Yoneoka, Toshiaki; Terai, Takayuki; Takahashi, Yoichi

    1997-09-01

    Yttrium sesquioxide has been proposed as a promising candidate material for collector electrodes used in the laser enrichment system of uranium-235. For this purpose, yttria is expected to be compatible with molten uranium and electrically conductive. A corrosion test of yttria with molten lanthanum as a simulating metal for uranium and a measurement of its electrical conductivity under extremely low oxygen pressure were performed. It was shown from the corrosion test that a yttria sample was considerably corroded by the molten lanthanum at 1513 K and the maximum corrosion depth for 5 Ms was 0.162 mm. The electrical conductivity of hypo-stoichiometric yttria reduced by titanium was higher than that of pure germanium at room temperature (2.1 S/m). The oxygen pressures equilibrated with the yttria specimens were estimated to discuss the relation to measured conductivities.

  18. Proximal spectral sensing to monitor phytoremediation of metal - contaminated soils

    NARCIS (Netherlands)

    Rathod, P.H.; Rossiter, D.; Noomen, M.; van der Meer, F.D.

    2013-01-01

    Assessment of soil contamination and its long-term monitoring are necessary to evaluate the effectiveness of phytoremediation systems. Spectral sensing-based monitoring methods promise obvious benefits compared to field-based methods: lower cost, faster data acquisition and better spatio-temporal

  19. Polymer Electrolyte-Based Ambient Temperature Oxygen Microsensors for Environmental Monitoring

    Science.gov (United States)

    Hunter, Gary W.; Xu, Jennifer C.; Liu, Chung-Chiun

    2011-01-01

    An ambient temperature oxygen microsensor, based on a Nafion polymer electrolyte, has been developed and was microfabricated using thin-film technologies. A challenge in the operation of Nafion-based sensor systems is that the conductivity of Nafion film depends on the humidity in the film. Nafion film loses conductivity when the moisture content in the film is too low, which can affect sensor operation. The advancement here is the identification of a method to retain the operation of the Nafion films in lower humidity environments. Certain salts can hold water molecules in the Nafion film structure at room temperature. By mixing salts with the Nafion solution, water molecules can be homogeneously distributed in the Nafion film increasing the film s hydration to prevent Nafion film from being dried out in low-humidity environment. The presence of organics provides extra sites in the Nafion film to promote proton (H+) mobility and thus improving Nafion film conductivity and sensor performance. The fabrication of ambient temperature oxygen microsensors includes depositing basic electrodes using noble metals, and metal oxides layer on one of the electrode as a reference electrode. The use of noble metals for electrodes is due to their strong catalytic properties for oxygen reduction. A conducting polymer Nafion, doped with water-retaining components and extra sites facilitating proton movement, was used as the electrolyte material, making the design adequate for low humidity environment applications. The Nafion solution was coated on the electrodes and air-dried. The sensor operates at room temperature in potentiometric mode, which measures voltage differences between working and reference electrodes in different gases. Repeat able responses to 21-percent oxygen in nitrogen were achieved using nitrogen as a baseline gas. Detection of oxygen from 7 to 21 percent has also been demonstrated. The room-temperature oxygen micro sensor developed has extremely low power

  20. Capacity training for the personnel of radiation monitoring in metal recycling

    International Nuclear Information System (INIS)

    Caveda Ramos, C.A.; Dominguez Ley, O.

    2013-01-01

    In this work it a course for training for the personnel involved in the radiation monitoring of metal recycling is presented. The contents were elaborated taken into account the IAEA recommendations for the development of capacity and training activities in radiological safety and in the Guide for the control of radioactive material in metal recycling. The program is divided in eleven parts and the duration time is two weeks. Among the main covered topics are the requirements for radiation monitoring in metal recycling; response to detection of radioactive material and effects of the ionizing radiation in man and environment

  1. Early warning monitoring and risk assessment on heavy metals in Shangba drinking water source in Nanjing

    Directory of Open Access Journals (Sweden)

    FU Yin

    2013-12-01

    Full Text Available Heavy metal changes in Shangba drinking water source of Nanjing had been studied since the end of 2012 to the first of 2013, based on the analysis on continuous automatic monitoring data for Hg, As, Cu, Pb and Cd. Health risk caused by heavy metal was evaluated to show that all heavy metal contents monitored could meet the standard of drinking water, and the concerned health risk is at lower level than the maximum acceptable level of risk recommended by international Commission on Radiological Protection (ICRP, which means that the water has lower risk. Experimental results on luminescent bacteria toxicity demonstrated that the water source was at safe level.

  2. Monitoring of heavy metal concentrations in home outdoor air using moss bags

    Energy Technology Data Exchange (ETDEWEB)

    Rivera, Marcela, E-mail: arivera@creal.ca [Centre for Research in Environmental Epidemiology CREAL, Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona (Spain); Universitat Pompeu Fabra, Barcelona (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Zechmeister, Harald [University of Vienna, Faculty of Life Sciences, Vienna (Austria); Medina-Ramon, Mercedes; Basagana, Xavier [Centre for Research in Environmental Epidemiology CREAL, Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Foraster, Maria [Centre for Research in Environmental Epidemiology CREAL, Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona (Spain); Universitat Pompeu Fabra, Barcelona (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Bouso, Laura [Centre for Research in Environmental Epidemiology CREAL, Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Moreno, Teresa [Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Barcelona (Spain); Solanas, Pascual; Ramos, Rafael [Research Unit, Family Medicine, Girona, Jordi Gol Institute for Primary Care Research (IDIAP Jordi Gol), Catalan Institute of Health, Catalunya (Spain); Department of Medical Sciences, School of Medicine, University of Girona (Spain); Koellensperger, Gunda [University of Natural Resources and Applied Life Sciences, Vienna (Austria); Deltell, Alexandre [Polytechnic School, GREFEMA, University of Girona (Spain); Vizcaya, David [Centre for Research in Environmental Epidemiology CREAL, Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona (Spain); Universitat Pompeu Fabra, Barcelona (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain)

    2011-04-15

    One monitoring station is insufficient to characterize the high spatial variation of traffic-related heavy metals within cities. We tested moss bags (Hylocomium splendens), deployed in a dense network, for the monitoring of metals in outdoor air and characterized metals' long-term spatial distribution and its determinants in Girona, Spain. Mosses were exposed outside 23 homes for two months; NO{sub 2} was monitored for comparison. Metals were not highly correlated with NO{sub 2} and showed higher spatial variation than NO{sub 2}. Regression models explained 61-85% of Cu, Cr, Mo, Pb, Sb, Sn, and Zn and 72% of NO{sub 2} variability. Metals were strongly associated with the number of bus lines in the nearest street. Heavy metals are an alternative traffic-marker to NO{sub 2} given their toxicological relevance, stronger association with local traffic and higher spatial variability. Monitoring heavy metals with mosses is appealing, particularly for long-term exposure assessment, as mosses can remain on site many months without maintenance. - Research highlights: > Moss bags can be used to measure the metal's long-term spatial distribution within cities. > Heavy metals in mosses are not highly correlated with ambient NO{sub 2} concentrations. > Heavy metals show higher spatial variation and association with traffic than NO{sub 2}. > Bus lines in the nearest street explain 75-85% of Mo, Cr, Sb, Sn and Cu variability. > Moss bags are useful for long-term at home exposure assessment in epidemiological studies. - The long-term spatial distribution of heavy metals, measured with moss bags, is mainly determined by proximity to bus lines.

  3. Monitoring of heavy metal concentrations in home outdoor air using moss bags

    International Nuclear Information System (INIS)

    Rivera, Marcela; Zechmeister, Harald; Medina-Ramon, Mercedes; Basagana, Xavier; Foraster, Maria; Bouso, Laura; Moreno, Teresa; Solanas, Pascual; Ramos, Rafael; Koellensperger, Gunda; Deltell, Alexandre; Vizcaya, David

    2011-01-01

    One monitoring station is insufficient to characterize the high spatial variation of traffic-related heavy metals within cities. We tested moss bags (Hylocomium splendens), deployed in a dense network, for the monitoring of metals in outdoor air and characterized metals' long-term spatial distribution and its determinants in Girona, Spain. Mosses were exposed outside 23 homes for two months; NO 2 was monitored for comparison. Metals were not highly correlated with NO 2 and showed higher spatial variation than NO 2 . Regression models explained 61-85% of Cu, Cr, Mo, Pb, Sb, Sn, and Zn and 72% of NO 2 variability. Metals were strongly associated with the number of bus lines in the nearest street. Heavy metals are an alternative traffic-marker to NO 2 given their toxicological relevance, stronger association with local traffic and higher spatial variability. Monitoring heavy metals with mosses is appealing, particularly for long-term exposure assessment, as mosses can remain on site many months without maintenance. - Research highlights: → Moss bags can be used to measure the metal's long-term spatial distribution within cities. → Heavy metals in mosses are not highly correlated with ambient NO 2 concentrations. → Heavy metals show higher spatial variation and association with traffic than NO 2 . → Bus lines in the nearest street explain 75-85% of Mo, Cr, Sb, Sn and Cu variability. → Moss bags are useful for long-term at home exposure assessment in epidemiological studies. - The long-term spatial distribution of heavy metals, measured with moss bags, is mainly determined by proximity to bus lines.

  4. On high temperature internal friction in metallic glasses

    International Nuclear Information System (INIS)

    Zolotukhin, I.V.; Kalinin, Yu.E.; Roshchupkin, A.M.

    1992-01-01

    High temperature background of internal friction in amorphous lanthanum-aluminium alloys was investigated. More rapid growth of internal friction was observed at temperature ∼ 453 K reaching maximal value at 495 K. Crystallization process was accompanied by decrease of internal friction. Increase of mechanical vibration frequency to 1000 Hz leads to rise of internal friction background in the range of room temperatures and to decrease at temperatures above 370 K. Bend was observed on temperature dependence of internal friction at 440 K

  5. Monitoring of heavy metals in selected Water Supply Systems in Poland, in relation to current regulations

    Science.gov (United States)

    Szuster-Janiaczyk, Agnieszka; Zeuschner, Piotr; Noga, Paweł; Skrzypczak, Marta

    2018-02-01

    The study presents an analysis of water quality monitoring in terms of the content of heavy metals, which is conducted in three independent water supply systems in Poland. The analysis showed that the monitoring of heavy metals isn't reliable - both the quantity of tested water samples and the location of the monitoring points are the problem. The analysis of changes in water quality from raw water to tap water was possible only for one of the analysed systems and indicate a gradual deterioration of water quality, although still within acceptable limits of legal regulations.

  6. "Periodic-table-style" paper device for monitoring heavy metals in water.

    Science.gov (United States)

    Li, Miaosi; Cao, Rong; Nilghaz, Azadeh; Guan, Liyun; Zhang, Xiwang; Shen, Wei

    2015-03-03

    If a paper-based analytical device (μ-PAD) could be made by printing indicators for detection of heavy metals in chemical symbols of the metals in a style of the periodic table of elements, it could be possible for such μ-PAD to report the presence and the safety level of heavy metal ions in water simultaneously and by text message. This device would be able to provide easy solutions to field-based monitoring of heavy metals in industrial wastewater discharges and in irrigating and drinking water. Text-reporting could promptly inform even nonprofessional users of the water quality. This work presents a proof of concept study of this idea. Cu(II), Ni(II), and Cr(VI) were chosen to demonstrate the feasibility, specificity, and reliability of paper-based text-reporting devices for monitoring heavy metals in water.

  7. Thin layer activation : on-line monitoring of metal loss in process plant

    International Nuclear Information System (INIS)

    Boulton, L.H.; Wallace, G.

    1993-01-01

    Corrosion, erosion and wear of metals is a common cause of failure in some process plant and equipment. Monitoring of these destructive effects has been done for many years to help plant engineers minimise the damage, in order to avoid unexpected failures and unscheduled shutdowns. Traditional methods of monitoring, such as standard NDT techniques, inform the engineer of what has happened, providing data such as culmulative loss of wall thickness. The modern approach to monitoring however, is to employ a technique which gives both current loss rates as well as integrated losses. Thin Layer Activation (TLA) provides on-line monitoring of corrosion, erosion and wear of metals, to a high degree of accuracy. It also gives cumulative information which can be backed up with weight-loss results if required. Thus current rather than historical loss rates are measured before any significant loss of metal has occurred. (author). 14 refs., 2 figs

  8. Survey of instrumentation used for monitoring metals in water

    Energy Technology Data Exchange (ETDEWEB)

    Quinby-Hunt, M.S.

    1978-06-01

    A study was conducted of instrumentation used to determine metals in water. Several of the techniques most commonly used for analysis and routine determinations of metals in water are shown in Table 1. They are atomic absorption spectroscopy, both flame and flameless, atomic emission spectroscopy using conventional flame sources and inductively-coupled plasma sources, and ultraviolet-visible absorption techniques. Other less frequently employed methods are x-ray fluorescence analysis using both photon and charged particle excitation with energy-dispersive and wavelength-dispersive spectral analysis. Also electrochemical techniques and activation analysis are studied.

  9. Study of the temperature dependence of giant magnetoresistance in metallic granular composite

    International Nuclear Information System (INIS)

    Ju Sheng; Li, Z.-Y.

    2002-01-01

    The temperature dependence of the giant magnetoresistance of metallic granular composite is studied. It is considered that the composite contains both large magnetic grains with surface spin S' and small magnetic impurities. It is found that the decrease of surface spin S' of grain is the main cause of an almost linear decrease of giant magnetoresistance with the increase of temperature in high temperature range. The magnetic impurities, composed of several atoms, lead to an almost linear increase of the giant magnetoresistance with the decrease of temperature in low temperature range. Our calculations are in good agreement with recent experimental data for metallic nanogranular composites

  10. Experiences of the Use of Bio monitors for Heavy Metal Pollution Control in Almendares River

    International Nuclear Information System (INIS)

    Olivares- Rieumont, S.; Lima, L.; De la Rosa, D.; Martinez, F.; Borroto, J.; Columbie, I.; Sanchez, M.J.

    2003-01-01

    Full Text: This work is the first approach to establish a monitoring system for heavy metals in the Almendares Vento Basin. This basin is the most important watershed of Havana City, which main river is the Almendares River, that with 42 km of length goes through 5 municipalities, where live more than 500,000 inhabitants. The river receives a large pollution loads from more than 50 pollution sources of Havana City. Inputs of toxic substances like heavy metals come from the industries located along the river and tributaries, the urban discharges and from important speedways in both shores of the river. In the work, concentrations of Cd, Pb, Zn, Cu, Ni, Co and Cr in sediments, water, gastropod species Tarebia granifera Lamarck, macrophyte Eichhornia Crassipes and fish from the specie Gambusia were evaluated at 14 stations during the dry season of 2003. Concentrations of copper and lead in water samples exceeded applicable guidelines for many of the sites monitored in the river basin. Heavy metals in sediments were analysed using three-stage sequential extraction procedure. In sediments high contents of studied metals were found in the bioavailable fraction. Some stations were highly polluted with all elements. Two main sources of pollution with heavy metals could be identified in the basin due to the higher concentration of most of the studied metals in the analized sampling stations. Pb concentrations were high in almost all the stations. Similar behaviour was found for the metal concentration in Eichhornia Crassipes roots, that appear to have an interesting potential as bio monitor of the pollution with heavy metals. Tarebia granifera Lamarck only could be found in 5 of the 14 stations monitored, and it presence is related with the quality of the river water. The magnitude of contamination was estimated by the comparison between local backgrounds and concentration of metals measured. Only high concentration of Zn were found in the Gambusia tissue, and no

  11. Application of a chronoamperometric measurement to the on-line monitoring of a lithium metal reduction for uranium oxide

    Science.gov (United States)

    Kim, Tack-Jin; Cho, Young-Hwan; Choi, In-Kyu; Kang, Jun-Gill; Song, Kyuseok; Jee, Kwang-Yong

    2008-04-01

    Both a potentiometric and a chronoamperometric electrochemical technique have been applied in an attempt to develop an efficient method for an on-line monitoring of a lithium metal reduction process of uranium oxides at a high-temperature in a molten salt medium. As a result of this study, it was concluded that the chronoamperometric method provided a simple and effective way for a direct on-line monitoring measurement of a lithium metal reduction process of uranium oxides at 650 °C by the measuring electrical currents dependency on a variation of the reduction time for the reaction. A potentiometric method, by adopting a homemade oxide ion selective electrode made of ZrO 2 stabilized by a Y 2O 3 doping, however, was found to be inappropriate for an on-line monitoring of the reduction reaction of uranium oxide in the presence of lithium metal due to an abnormal behavior of the adopted electrodes. The observed experimental results were discussed in detail by comparing them with previously published experimental data.

  12. Application of a chronoamperometric measurement to the on-line monitoring of a lithium metal reduction for uranium oxide

    International Nuclear Information System (INIS)

    Kim, Tack-Jin; Cho, Young-Hwan; Choi, In-Kyu; Kang, Jun-Gill; Song, Kyuseok; Jee, Kwang-Yong

    2008-01-01

    Both a potentiometric and a chronoamperometric electrochemical technique have been applied in an attempt to develop an efficient method for an on-line monitoring of a lithium metal reduction process of uranium oxides at a high-temperature in a molten salt medium. As a result of this study, it was concluded that the chronoamperometric method provided a simple and effective way for a direct on-line monitoring measurement of a lithium metal reduction process of uranium oxides at 650 o C by the measuring electrical currents dependency on a variation of the reduction time for the reaction. A potentiometric method, by adopting a homemade oxide ion selective electrode made of ZrO 2 stabilized by a Y 2 O 3 doping, however, was found to be inappropriate for an on-line monitoring of the reduction reaction of uranium oxide in the presence of lithium metal due to an abnormal behavior of the adopted electrodes. The observed experimental results were discussed in detail by comparing them with previously published experimental data

  13. Monitoring of essential and toxic metals in imported herbal teas ...

    African Journals Online (AJOL)

    Twenty eight samples of commonly consumed herbal tea bags were purchased from major supermarkets in Port-Harcourt, Yenagoa and Owerri in Southern Nigeria. They were digested, ashed and analysed using atomic absorption spectroscopy (AAS). Heavy metal concentration varied among the different brands of herbal ...

  14. Monitoring of essential and toxic metals in imported herbal teas ...

    African Journals Online (AJOL)

    ADOWIE PERE

    concentrated and in turn enter the food chain and ultimately pose serious human health risk to consumers (Ansari et al., 2007; Weldegebriel et al.,. 2012; Rezaee et al., 2014). However, the evaluation of essential and toxic metals in teas is of great importance considering the potential health risk to habitual tea drinkers if ...

  15. Liquid-crystal indicators for temperature monitoring at the surface of pipeline insulators

    International Nuclear Information System (INIS)

    Zvonarev, M.G.; Igon'kin, E.L.; Sidel'nikova, G.A.; Chernyshev, S.K.

    1986-01-01

    The design and specifications of cholesteric type liquid-crystal indicators used for temperature monitoring at NPP an TPP pipeline insulators if temperature deviation makes up ± 1 deg C, are considered. The liquid-crystal indicators operate in the temperature range from room temperature to 200-250 deg C

  16. Online monitoring of corrosion behavior in molten metal using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Zeng, Qiang; Pan, Congyuan; Li, Chaoyang; Fei, Teng; Ding, Xiaokang; Du, Xuewei; Wang, Qiuping

    2018-04-01

    The corrosion behavior of structure materials in direct contact with molten metals is widespread in metallurgical industry. The corrosion of casting equipment by molten metals is detrimental to the production process, and the corroded materials can also contaminate the metals being produced. Conventional methods for studying the corrosion behavior by molten metal are offline. This work explored the application of laser-induced breakdown spectroscopy (LIBS) for online monitoring of the corrosion behavior of molten metal. The compositional changes of molten aluminum in crucibles made of 304 stainless steel were obtained online at 1000 °C. Several offline techniques were combined to determine the corrosion mechanism, which was highly consistent with previous studies. Results proved that LIBS was an efficient method to study the corrosion mechanism of solid materials in molten metal.

  17. Creep behaviour of austenitic stainless steels, base and weld metals used in liquid metal fast breeder reactors, during temperature variations

    International Nuclear Information System (INIS)

    Felsen, M.F.

    1982-07-01

    Creep rupture and deformation during temperature variations have been studied for 316 austenitic steel, base and weld metals. Loaded specimens were heated to 900 0 C or 1000 0 C and maintained at this temperature for different durations. The heating rate to these temperatures was between 5 and 50 0 C h -1 , whilst the cooling rate was between 5 and 20 0 C h -1 . The above tests were coupled with short time creep and tensile tests (straining rate 10 -2 h -1 to 10 3 h -1 ) at constant temperature. These tests were used for predicting the creep behaviour of the materials under changing temperature condition. The predictions were in good agreement with the changing temperature and creep experimental results. In addition, a correlation between certains tensile properties, such as the rupture time as a function of stress was observed at high temperature

  18. Monitoring detachment and diffusion of metallic species in polycarbonate

    Science.gov (United States)

    Bencomo, M.; Castro-Colín, M.; López, J. A.; Ramírez-Homs, E.

    2013-07-01

    Photon absorption is known to create peroxy radicals in polymers, in a process that entails the removal of hydrogen atoms and the subsequent breakage of bonds. Bond-breaking is found to free, from the polymeric matrix, metallic additives which are then able to diffuse out, as evidenced by the change in both the metallic fluorescence yield and the XPS profiles of C, N, and O. Polycarbonate was artificially weathered using UV radiation from mercury emission lines at 365, 405 and 435 nm, followed by thermal treatment. The UV wavelengths used have energies comparable to those of covalent bonds found in polymeric chains. Both processes, light exposure and thermal, have the purpose of stimulating the degradation of polycarbonate.

  19. Temperature monitoring: the consequences and prevention of mild ...

    African Journals Online (AJOL)

    varying environmental temperatures. As thermoregulatory responses are inhibited (by drugs), the range of environmental temperatures over which normal core temperature can be maintained decreases. For example, when shivering is prevented following the administration of muscle relaxants, hypothermia will develop in ...

  20. Lightweight and Flexible Metal Halide Perovskite Thin Films for High Temperature Solar Cells

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of this project is to develop metal halide perovskites (MHPs) based solar cells for high temperature operation. MHPs have been recently discovered as high...

  1. Surface chemistry of metals and their oxides in high temperature water

    International Nuclear Information System (INIS)

    Tomlinson, M.

    1975-01-01

    Examination of oxide and metal surfaces in water at high temperature by a broad spectrum of techniques is bringing understanding of corrosion product movement and alleviation of activity transport in CANDU-type reactor primary coolant circuits. (Author)

  2. Warehouse multipoint temperature and humidity monitoring system design based on Kingview

    Science.gov (United States)

    Ou, Yanghui; Wang, Xifu; Liu, Jingyun

    2017-04-01

    Storage is the key link of modern logistics. Warehouse environment monitoring is an important part of storage safety management. To meet the storage requirements of different materials, guarantee their quality in the greatest extent, which has great significance. In the warehouse environment monitoring, the most important parameters are air temperature and relative humidity. In this paper, a design of warehouse multipoint temperature and humidity monitoring system based on King view, which realizes the multipoint temperature and humidity data real-time acquisition, monitoring and storage in warehouse by using temperature and humidity sensor. Also, this paper will take the bulk grain warehouse as an example and based on the data collected in real-time monitoring, giving the corresponding expert advice that combined with the corresponding algorithm, providing theoretical guidance to control the temperature and humidity in grain warehouse.

  3. A method for the monitoring of metal recrystallization based on the in-situ measurement of the elastic energy release using neutron diffraction

    International Nuclear Information System (INIS)

    Christien, F.; Le Gall, R.; Telling, M. T. F.; Knight, K. S.

    2015-01-01

    A method is proposed for the monitoring of metal recrystallization using neutron diffraction that is based on the measurement of stored energy. Experiments were performed using deformed metal specimens heated in-situ while mounted at the sample position of the High Resolution Powder Diffractometer, HRPD (ISIS Facility), UK. Monitoring the breadth of the resulting Bragg lines during heating not only allows the time-dependence (or temperature-dependence) of the stored energy to be determined but also the recrystallized fraction. The analysis method presented here was developed using pure nickel (Ni270) specimens with different deformation levels from 0.29 to 0.94. In situ temperature ramping as well as isothermal annealing was undertaken. The method developed in this work allows accurate and quantitative monitoring of the recrystallization process. The results from neutron diffraction are satisfactorily compared to data obtained from calorimetry and hardness measurements

  4. A method for the monitoring of metal recrystallization based on the in-situ measurement of the elastic energy release using neutron diffraction.

    Science.gov (United States)

    Christien, F; Telling, M T F; Knight, K S; Le Gall, R

    2015-05-01

    A method is proposed for the monitoring of metal recrystallization using neutron diffraction that is based on the measurement of stored energy. Experiments were performed using deformed metal specimens heated in-situ while mounted at the sample position of the High Resolution Powder Diffractometer, HRPD (ISIS Facility), UK. Monitoring the breadth of the resulting Bragg lines during heating not only allows the time-dependence (or temperature-dependence) of the stored energy to be determined but also the recrystallized fraction. The analysis method presented here was developed using pure nickel (Ni270) specimens with different deformation levels from 0.29 to 0.94. In situ temperature ramping as well as isothermal annealing was undertaken. The method developed in this work allows accurate and quantitative monitoring of the recrystallization process. The results from neutron diffraction are satisfactorily compared to data obtained from calorimetry and hardness measurements.

  5. Regulatory quality control in the metal and semi metal environmental monitoring program at IPEN/CNEN-SP

    International Nuclear Information System (INIS)

    Faustino, Mainara G.; Silva, Doulgas Batista; Monteiro, Lucilena R.; Dantas, Elizabeth S.K.; Pires, Maria Aparecida F.; Cotrim, Marycel E.B.

    2013-01-01

    The CONAMA's Resolution 430 recently published in May 13 th of 2011, that completes and modifies the Resolution 357/2005, defined new quality standards to perform liquid effluent monitoring essays in order to allow the release in the public sewer system. This Resolution has established that the essay laboratories must be certified by Brazilian National Metrology, Normalization and Industrial Quality Institute - INMETRO and also count with an implemented quality control system. Thereby this publication affected directly IPEN's Environmental Monitoring Program of Stables Chemical Compound (PMA-Q), performed since 2007. In this program, 20 parameters related to the metallic and non-metallic chemical elements content are monitored by using sensitive analytical techniques such as graphite furnace atomic absorption spectrometry - GF-AAS or inductively coupled plasma spectrometry - ICP-OES. Therefore this paper presents improvements to determine the laboratory individual performance performed by GF-AAS and ICP-OES. To achieve the legislation compliance for these parameters, the following actions were implemented: the construction of control charts (internal quality control) and the participation of the laboratory in interlaboratory proficiency tests (external quality control). These actions are presented and discussed with the results of elements such as Arsenic and Lead that are analyzed through GF-AAS as well as Chromium, Cooper, Zinc, Iron and Nickel, that are analyzed through ICP-OES. These actions of quality control allowed the continuous monitoring of laboratory performance, the identification and resolution of analytic problems and interlaboratory differences, provide additional confidence to monitoring program. (author)

  6. Simulation study based on the single-point temperature monitoring system of LabVIEW

    Science.gov (United States)

    Wu, Yongling; Yang, Na; Liu, Shuping; Pan, Xiaohui; Wang, Wenjiang

    2014-12-01

    This paper takes LabVIEW2012 as a development platform, creating a J-type thermocouple sensor and the NI USB-6229 data acquisition card and other hardware emulation circuitry which combined with the PC designed a single-point temperature monitoring system. Through simulation experiments, the system has a collection interval, the sampling rate per channel sampling on the temperature limit set by the user function and it also has the function of real-time display the current temperature, the temperature limit alarm, maximum temperature, minimum temperature display and a temperature history data query. This system can be used for temperature monitoring of life, research, industrial control, environmental monitoring, biomedical, tobacco processing, greenhouse cultivation, livestock breeding and other fields, which has important significance and practical value.

  7. Large-Scale Wireless Temperature Monitoring System for Liquefied Petroleum Gas Storage Tanks.

    Science.gov (United States)

    Fan, Guangwen; Shen, Yu; Hao, Xiaowei; Yuan, Zongming; Zhou, Zhi

    2015-09-18

    Temperature distribution is a critical indicator of the health condition for Liquefied Petroleum Gas (LPG) storage tanks. In this paper, we present a large-scale wireless temperature monitoring system to evaluate the safety of LPG storage tanks. The system includes wireless sensors networks, high temperature fiber-optic sensors, and monitoring software. Finally, a case study on real-world LPG storage tanks proves the feasibility of the system. The unique features of wireless transmission, automatic data acquisition and management, local and remote access make the developed system a good alternative for temperature monitoring of LPG storage tanks in practical applications.

  8. Large-Scale Wireless Temperature Monitoring System for Liquefied Petroleum Gas Storage Tanks

    Directory of Open Access Journals (Sweden)

    Guangwen Fan

    2015-09-01

    Full Text Available Temperature distribution is a critical indicator of the health condition for Liquefied Petroleum Gas (LPG storage tanks. In this paper, we present a large-scale wireless temperature monitoring system to evaluate the safety of LPG storage tanks. The system includes wireless sensors networks, high temperature fiber-optic sensors, and monitoring software. Finally, a case study on real-world LPG storage tanks proves the feasibility of the system. The unique features of wireless transmission, automatic data acquisition and management, local and remote access make the developed system a good alternative for temperature monitoring of LPG storage tanks in practical applications.

  9. Relationship between thermal expansion coefficient and glass transition temperature in metallic glasses

    International Nuclear Information System (INIS)

    Kato, H.; Chen, H.-S.; Inoue, A.

    2008-01-01

    The thermal expansion coefficients of 13 metallic glasses were measured using a thermo-mechanical analyser. A unique correlation was found between the linear thermal expansion coefficient and the glass transition temperature-their product is nearly constant ∼8.24 x 10 -3 . If one assumes the Debye expression for thermal activation, the total linear thermal expansion up to glass transition temperature (T g ) is reduced to 6 x 10 -3 , nearly 25% of that at the fusion of pure metals

  10. Large-Scale Wireless Temperature Monitoring System for Liquefied Petroleum Gas Storage Tanks

    OpenAIRE

    Fan, Guangwen; Shen, Yu; Hao, Xiaowei; Yuan, Zongming; Zhou, Zhi

    2015-01-01

    Temperature distribution is a critical indicator of the health condition for Liquefied Petroleum Gas (LPG) storage tanks. In this paper, we present a large-scale wireless temperature monitoring system to evaluate the safety of LPG storage tanks. The system includes wireless sensors networks, high temperature fiber-optic sensors, and monitoring software. Finally, a case study on real-world LPG storage tanks proves the feasibility of the system. The unique features of wireless transmission, au...

  11. Monitoring and Prediction of the Liquid Steel Temperature in the Ladle and Tundish

    OpenAIRE

    Dorčák, Ľ.; Terpák, J.

    2006-01-01

    This article is focused on the description of the main features of an online system for the real time monitoring and prediction of the liquid steel temperature in the ladle and tundish. Monitoring and prediction are based on a combination of analytical and statistical methods. Thus e.g., the temperature profiles of the walls are calculated using multi-layer implicit difference scheme taking into account the current temperature of the steel, preheating of the ladle and/or tundish, properties o...

  12. Innovative Health Monitoring Techniques for High Temperature Composites

    Data.gov (United States)

    National Aeronautics and Space Administration — High temperature composite materials, which include ceramic matrix composites (CMCs), carbon-carbon and polyimide composites, will be essential for future space...

  13. Monitoring of heavy metal load - by mosses or rain water chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Ruoho-Airola, T. [Finnish Meteorological Inst., Helsinki (Finland); Maekelae, K. [National Board of Waters and the Environment, Helsinki (Finland)

    1995-12-31

    The deposition of heavy metals is usually determined from precipitation chemistry but the moss technique has been increasingly used, particularly in the Nordic countries. Some international monitoring programmes, e.g. UN/ECE Integrated Monitoring, give them as alternative methods. However, their comparability has not been sufficiently determined. This study compares the two monitoring methods for Pb, Cd, Cu and Zn, which have different sources. The metal industry is an important source of Pb and Cd emissions. Long- range transport as well as traffic and local emissions are also important sources for Pb. The use of fertilizers and fossil fuels also result in Cd emissions. Cu and Zn are emitted from metal industries and local sources. Unlike Pb and Cd, Cu and Zn are essential elements for living organisms. Cu and Zn are needed in many enzymes and Zn in proteins. Mosses are thought to take all their nutrients from the air. The deposition of heavy metals is also effectively retained by mosses and may be used to indicate levels of heavy metal deposition. In northern countries the mosses are isolated from air (and therefore also from deposition) by snow in winter. In this study both the bulk deposition of the whole year (later `total deposition`) and the bulk deposition of the snow-free period (later `bare ground deposition`) are compared to the metal concentrations in mosses. (author)

  14. Low speed sliding behavior of metal-ceramic couples at temperatures up to 800 C

    Science.gov (United States)

    Murray, S. F.; Calabrese, Salvadore J.

    1993-05-01

    The objective of this work was to select a small number of alloys with favorable tribological characteristics and suitable high temperature properties, and evaluate their sliding performance against ceramics as a function of temperature. Five candidate alloys were chosen. They included four alloys containing cobalt and molybdenum, or tungsten and a nickel-base superalloy with good high-temperature strength. All of these alloys are known to form oxide films that protect sliding surfaces from damage at high temperature. These metals were slid against five ceramic flats of different compositions in slow speed reciprocating sliding tests. The test geometry was a metal pin sliding against a ceramic flat. Coefficients of friction and wear rates were measured over a temperature range from 25 to 800 C. Material transfer from the metals to the ceramics played a major role in most of the results. In the low-to intermediate-temperature range, the transferred films (with the exception of silicon carbide) coated the ceramic surface and sliding was essentially metal vs the transferred metal film. At higher temperatures, depending on the alloy composition, the transferred films oxidized and provided reasonable low friction and, in some instances, very low wear.

  15. Tool Monitoring and Electronic Event Logging for Sheet Metal Forming Processes

    Directory of Open Access Journals (Sweden)

    Gerd Heiserich

    2010-06-01

    Full Text Available This contribution describes some innovative solutions regarding sensor systems for tool monitoring in the sheet metal industry. Autonomous and tamper-proof sensors, which are integrated in the forming tools, can detect and count the strokes carried out by a sheet metal forming press. Furthermore, an electronic event logger for documentary purposes and quality control was developed. Based on this technical solution, new business models such as leasing of sheet metal forming tools can be established for cooperation among enterprises. These models allow usage-based billing for the contractors, taking the effectively produced number of parts into account.

  16. Direct high-temperature ohmic heating of metals as liquid pipes.

    Science.gov (United States)

    Grosse, A V; Cahill, J A; Liddell, W L; Murphy, W J; Stokes, C S

    1968-05-03

    When a sufficiently high electric current is passed through a liquid metal, the electromagnetic pressure pinches off the liquid metal and interrupts the flow of current. For the first time the pinch effect has been overcome by use of centrifugal acceleration. By rotation of a pipe of liquid metal, tin or bismuth or their alloys, at sufficiently high speed, it can be heated electrically without intermission of the electric current. One may now heat liquid metallic substances, by resistive (ohmic) heating, to 5000 degrees K and perhaps higher temperatures.

  17. Monitoring of Soil Remediation Process in the Metal Mining Area

    Science.gov (United States)

    Kim, Kyoung-Woong; Ko, Myoung-Soo; Han, Hyeop-jo; Lee, Sang-Ho; Na, So-Young

    2016-04-01

    Stabilization using proper additives is an effective soil remediation technique to reduce As mobility in soil. Several researches have reported that Fe-containing materials such as amorphous Fe-oxides, goethite and hematite were effective in As immobilization and therefore acid mine drainage sludge (AMDS) may be potential material for As immobilization. The AMDS is the by-product from electrochemical treatment of acid mine drainage and mainly contains Fe-oxide. The Chungyang area in Korea is located in the vicinity of the huge abandoned Au-Ag Gubong mine which was closed in the 1970s. Large amounts of mine tailings have been remained without proper treatment and the mobilization of mine tailings can be manly occurred during the summer heavy rainfall season. Soil contamination from this mobilization may become an urgent issue because it can cause the contamination of groundwater and crop plants in sequence. In order to reduce the mobilization of the mine tailings, the pilot scale study of in-situ stabilization using AMDS was applied after the batch and column experiments in the lab. For the monitoring of stabilization process, we used to determine the As concentration in crop plants grown on the field site but it is not easily applicable because of time and cost. Therefore, we may need simple monitoring technique to measure the mobility or leachability which can be comparable with As concentration in crop plants. We compared several extraction methods to suggest the representative single extraction method for the monitoring of soil stabilization efficiency. Several selected extraction methods were examined and Mehlich 3 extraction method using the mixture of NH4F, EDTA, NH4NO3, CH3COOH and HNO3 was selected as the best predictor of the leachability or mobility of As in the soil remediation process.

  18. Room temperature desorption of helium-3 from metal tritides

    International Nuclear Information System (INIS)

    Beavis, L.C.; Kass, W.J.

    1976-10-01

    It has long been known that helium-3 accumulates in metal tritides as tritium decays. Early in life nearly 100% of the helium-3 is retained in the lattice, but when a critical concentration is reached (material dependent), the lattice will no longer retain the helium-3 and it is emitted at about the generation rate. Measurements were recently made on a number of erbium tritides with varying concentrations in the ditritide phase. The expected early release characteristics are observed for all of the samples. However, ditritides with higher tritium concentrations reach the rapid release state at much lower helium-3 concentrations. For instance, the helium to metal concentration for rapid release in the unsaturated ditritide is about 0.22, whereas it is only one-tenth this value in the saturated ditritide. The additional tritium in the tritide appears to be the cause of this effect

  19. Ultra Wide Band (UWB) Antenna Design for Metal Monitoring

    OpenAIRE

    Pratiwi, A. Asmi; Palantei, Elyas; Areni, Intan Sari; Djamaluddin, Dewiani

    2014-01-01

    UWB microstrip antenna has been designed using UWB technology and the principle of Microwave Imaging system that works at UWB frequencies. The Simulation performed using Ansoft HFSS version 13 software to construct the microstrip antenna with some important parameters, such as reflection coefficient (S) and radiation pattern. This purpose of the antenna is fetal detecting and monitoring system in dual band at (2.54 - 4.45) GHz with the bandwidth of 1.91 GHz and (6.53 -7.97) GHz with the b...

  20. Design and evaluation of an inexpensive radiation shield for monitoring surface air temperatures

    Science.gov (United States)

    Zachary A. Holden; Anna E. Klene; Robert F. Keefe; Gretchen G. Moisen

    2013-01-01

    Inexpensive temperature sensors are widely used in agricultural and forestry research. This paper describes a low-cost (~3 USD) radiation shield (radshield) designed for monitoring surface air temperatures in harsh outdoor environments. We compared the performance of the radshield paired with low-cost temperature sensors at three sites in western Montana to several...

  1. Remote Acoustic Emission Monitoring of Metal Ware and Welded Joints

    Science.gov (United States)

    Kapranov, Boris I.; Sutorikhin, Vladimir A.

    2017-10-01

    An unusual phenomenon was revealed in the metal-ultrasound interaction. Microwave sensor generates surface electric conductivity oscillations from exposure to elastic ultrasonic vibrations on regions of defects embracing micro-defects termed as “crack mouth.” They are known as the region of “acoustic activity,” method of Acoustic Emission (AE) method. It was established that the high phase-modulation coefficient of reflected field generates intentional Doppler radar signal with the following parameters: amplitude-1–5 nm, 6–30 dB adjusted to 70- 180 mm. This phenomenon is termed as “Gorbunov effect,” which is applied as a remote non-destructive testing method replacing ultrasonic flaw detection and acoustic emission methods.

  2. Platinum redispersion on metal oxides in low temperature fuel cells

    DEFF Research Database (Denmark)

    Tripkovic, Vladimir; Cerri, Isotta; Nagami, Tetsuo

    2013-01-01

    We have analyzed the aptitude of several metal oxide supports (TiO2, SnO2, NbO2, ZrO2, SiO2, Ta2O5 and Nb2O5) to redisperse platinum under electrochemical conditions pertinent to the Proton Exchange Membrane Fuel Cell (PEMFC) cathode. The redispersion on oxide supports in air has been studied in ...

  3. Improving catchment scale water quality modelling with continuous high resolution monitoring of metals in runoff

    Science.gov (United States)

    Saari, Markus; Rossi, Pekka; Blomberg von der Geest, Kalle; Mäkinen, Ari; Postila, Heini; Marttila, Hannu

    2017-04-01

    High metal concentrations in natural waters is one of the key environmental and health problems globally. Continuous in-situ analysis of metals from runoff water is technically challenging but essential for the better understanding of processes which lead to pollutant transport. Currently, typical analytical methods for monitoring elements in liquids are off-line laboratory methods such as ICP-OES (Inductively Coupled Plasma Optical Emission Spectroscopy) and ICP-MS (ICP combined with a mass spectrometer). Disadvantage of the both techniques is time consuming sample collection, preparation, and off-line analysis at laboratory conditions. Thus use of these techniques lack possibility for real-time monitoring of element transport. We combined a novel high resolution on-line metal concentration monitoring with catchment scale physical hydrological modelling in Mustijoki river in Southern Finland in order to study dynamics of processes and form a predictive warning system for leaching of metals. A novel on-line measurement technique based on micro plasma emission spectroscopy (MPES) is tested for on-line detection of selected elements (e.g. Na, Mg, Al, K, Ca, Fe, Ni, Cu, Cd and Pb) in runoff waters. The preliminary results indicate that MPES can sufficiently detect and monitor metal concentrations from river water. Water and Soil Assessment Tool (SWAT) catchment scale model was further calibrated with high resolution metal concentration data. We show that by combining high resolution monitoring and catchment scale physical based modelling, further process studies and creation of early warning systems, for example to optimization of drinking water uptake from rivers, can be achieved.

  4. Analytical expression for high-frequency dielectric function of metals at moderate temperatures

    Science.gov (United States)

    Veysman, M. E.; Röpke, G.; Reinholz, H.

    2018-01-01

    Analytical expressions are derived for the dielectric function of metals at moderate temperatures, determined by electron–phonon interactions, taking a quantum statistical approach and linear response theory as a basis. The obtained formulas permit one to calculate an effective electron–phonon collision frequency and the dielectric function of two-temperature plasmas for arbitrary laser radiation frequencies. Different limiting cases are considered.

  5. Comparison Of Different Noble Metal Catalysts For The Low Temperature Catalytic Partial Oxidation Of Methane

    Energy Technology Data Exchange (ETDEWEB)

    Rabe, S.; Truong, T.-B.; Vogel, F.

    2005-03-01

    The generation of synthesis gas at low temperatures can contribute to a more economic production of clean transportation fuels (Fischer-Tropsch liquids) from natural gas. In this report, the performance of different noble metal catalysts in a low temperature catalytic partial oxidation process is presented. (author)

  6. Evaluation of the effect of temperature on the stability of metal soaps ...

    African Journals Online (AJOL)

    The thermal stability of calcium and zinc dicarboxylates was studied. The kinetics of the decomposition was studied thermogravimetrically at various temperatures. The rates of the first stage decomposition were used to assess the effect of temperature on the susceptibility of the metal soaps of dicarboxylic acids to ...

  7. Evaluation of a Novel Temperature Sensing Probe for Monitoring and Controlling Glass Temperature in a Joule-Heated Glass Melter

    International Nuclear Information System (INIS)

    Watkins, A. D.; Musick, C. A.; Cannon, C.; Carlson, N. M.; Mullenix, P.D.; Tillotson, R. D.

    1999-01-01

    A self-verifying temperature sensor that employs advanced contact thermocouple probe technology was tested in a laboratory-scale, joule-heated, refractory-lined glass melter used for radioactive waste vitrification. The novel temperature probe monitors melt temperature at any given level of the melt chamber. The data acquisition system provides the real-time temperature for molten glass. Test results indicate that the self-verifying sensor is more accurate and reliable than classic platinum/rhodium thermocouple and sheath assemblies. The results of this test are reported as well as enhancements being made to the temperature probe. To obtain more reliable temperature measurements of the molten glass for improving production efficiency and ensuring consistent glass properties, optical sensing was reviewed for application in a high temperature environment

  8. Novel SICN Ceramics for Health Monitoring of High Temperature Systems

    National Research Council Canada - National Science Library

    Raj, Rishi

    2006-01-01

    The objective of this MEANS program was to develop new methodologies for quantifying the variability in the performance of high temperature systems by coupling basic concepts from materials science...

  9. The Design of Temperature and Humidity Chamber Monitor and Controller

    OpenAIRE

    Tibebu, Simachew

    2016-01-01

    The temperature and humidity chamber, (climate chamber) is a device located at the Technobothnia Education and Research Center that simulates different climate conditions. The simulated environment is used to test the capabilities of electrical equipment in different temperature and humidity conditions. The climate chamber, among other things houses a dedicated computer, the control PC, and a control software running in it which together are responsible for running and control-ling these simu...

  10. High-temperature performance of a new nickel-based filler metal for power generation application

    Energy Technology Data Exchange (ETDEWEB)

    Shingledecker, J.; Coleman, K. [Electric Power Research Institute, Charlotte, NC (United States); Siefert, J.; Tanzosh, J. [Babcok and Wilcox Research Center, Barberton, OH (United States); Newell, W. [Euroweld, Mooresville, NC (United States)

    2010-07-01

    A new nickel-based weld filler metal, EPRI P87, has been developed as a superior alternative to ERNiCr-3 for use in dissimilar metal welds (DMW) between ferritic and austenitic materials. EPRI P87 has a low coefficient of thermal expansion more closely matching alloys such as Grade 91 and 92 than other available filler metals. Additionally, the size of the carbon denuded region adjacent to the weld in the heat-affected-zone is minimized/eliminated by proper control of weld metal composition. In this work the high-temperature mechanical behavior of DMWs utilizing EPRI P87 (GTAW and GMAW processes) was characterized through tensile and long-term creep-rupture testing. Microstructure analysis was also conducted on tested specimens to evaluate the HAZ regions and failure modes. Performance of the weld metal and welded joints is discussed and compared with ERNiCr-3 and typical 9%Cr-MoV filler metals. (orig.)

  11. Biological monitoring of toxic metals - steel workers respiratory health survey

    International Nuclear Information System (INIS)

    Pinheiro, T.; Almeida, A. Bugalho de; Alves, L.; Freitas, M.C.; Moniz, D.; Alvarez, E.; Monteiro, P.; Reis, M.

    1999-01-01

    The aim of this work is to search for respiratory system aggressors to which workers are submitted in their labouring activity. Workers from one sector of a steel plant in Portugal, Siderurgia Nacional (SN), were selected according to the number of years of exposure and labouring characteristics. The work reports on blood elemental content alterations and lung function tests to determine an eventual bronchial hyper-reactivity. Aerosol samples collected permit an estimate of indoor air quality and airborne particulate matter characterisation to further check whether the elemental associations and alterations found in blood may derive from exposure. Blood and aerosol elemental composition was determined by PIXE and INAA. Respiratory affections were verified for 24% of the workers monitored. There are indications that the occurrence of affections can be associated with the total working years. The influence of long-term exposure, health status parameters, and lifestyle factors in blood elemental variations found was investigated

  12. Metal-Coated Optical Fibers for High Temperature Applications

    Science.gov (United States)

    Zeakes, Jason; Murphy, Kent; Claus, Richard; Greene, Jonathan; Tran, Tuan

    1996-01-01

    A DC magnetron sputtering system has been used to actively coat optical fibers with hermetic metal coatings during the fiber draw process. Thin films of Inconel 625 have been deposited on optical fibers and annealed in air at 2000 F. Scanning electron microscopy and Auger electron microscopy have been used to investigate the morphology and composition of the films prior to and following thermal cycling. Issues to be addressed include film adhesion, other coating materials, and a discussion of additional applications for this novel technology.

  13. Low-temperature properties of a superconducting disordered metal

    International Nuclear Information System (INIS)

    Graebner, J.E.; Golding, B.; Schutz, R.J.; Hsu, F.S.L.; Chen, H.S.

    1977-01-01

    Specific heat C/sub p/ and thermal conductivity kappa measurements between 0.1 and 10 K on the superconducting (T/sub c/ = 2.53 K) and structurally disordered metal Zr/sub 0.7/Pd/sub 0.3/ exhibit an approximately linear term in C/sub p/ and a T/sup 1.9/ dependence of kappa below T/sub c/. The magnitudes of these terms are close to those found for insulating glasses, thereby suggesting that disorder-induced localized excitations exist at similar densities in very different classes of disordered solids

  14. Low-temperature metallic liquid hydrogen: an ab-initio path-integral molecular dynamics perspective

    Science.gov (United States)

    Chen, Ji; Li, Xin-Zheng; Zhang, Qianfan; Probert, Matthew; Pickard, Chris; Needs, Richard; Michaelides, Angelos; Wang, Enge

    2013-03-01

    Experiments and computer simulations have shown that the melting temperature of solid hydrogen drops with pressure above about 65 GPa, suggesting that a low temperature liquid state might exist. It has also been suggested that this liquid state might be non-molecular and metallic, although evidence for such behaviour is lacking. Using a combination of ab initio path-integral molecular dynamics and the two-phase methods, we have simulated the melting of solid hydrogen under finite temperatures. We found an atomic solid phase from 500 to 800 GPa which melts at < 200 K. Beyond this and up to pressures of 1,200 GPa a metallic atomic liquid is stable at temperatures as low as 50 K. The quantum motion of the protons is critical to the low melting temperature in this system as ab initio simulations with classical nuclei lead to a considerably higher melting temperature of ~300 K across the entire pressure range considered.

  15. Study of radiation portal monitor and its application to metal recycling industry

    International Nuclear Information System (INIS)

    Pujol, L.; Lara-Calleja, S.; Suarez-Navarro, M. J.; Gonzalez-Gonzalez, J. A.

    2009-01-01

    The industry of the iron and the steel in one of the most important sectors in Spain for its economic development. the recycling of metallic materials as well as the import of metallic scrap is very significant. Several reports on accidental dispersion or smelting of radioactive sources in metal recycling industries confirm the possibility that radioactive material might be mixed with scrap. In consequence, this type of accident shows the necessity of a rigorous and specific radiation control of the sector. The control of these materials with radioactive content can be carried out with radiation portal monitors installed at the entrance of these industries. The detection of radioactive materials presents special features as the continuous background acquisition or the minimisation of the relatively large number of innocent/nuisance detections. In the present work, we study a radiation portal monitor, the FHT-1388-T Thermo-Eberline. This is one of the usual radiation portal systems installed at the entrance of the metal recycling industry. Se study the characteristics and parameters of this portal monitor to optimise its use. furthermore, we propose some rapid tests for radiation portal systems in metal recycling industry. (Author) 16 refs

  16. Surface intermediates on metal electrodes at high temperatures

    DEFF Research Database (Denmark)

    Zachau-Christiansen, Birgit; Jacobsen, Torben; Bay, Lasse

    1998-01-01

    The mechanisms widely conceived for the O(2)-reduction or H(2)-oxidation reactions in SOFC's involve intermediate O/H species adsorbed on the electrode surface. The presence of these intermediates is investigated by linear sweep voltammetry. In air at moderate temperatures (500 degrees C) Pt...... in contact with YSZ is covered with adsorbed oxygen which vanishes at high temperature (1000 degrees C). On Ni (YSZ) a specific layer of NiO is observed above the equilibrium potential while no surface species involving hydrogen can be identified at SOFC anode conditions. (C) 1998 Published by Elsevier...... Science B.V. All rights reserved....

  17. Induction apparatus monitoring structural strains in liquid-metal-cooled nuclear reactor

    International Nuclear Information System (INIS)

    Dean, S.A.; Evans, R.A.

    1981-01-01

    An improved method of monitoring induced torsional and linear strains in the internal structures of liquid metal cooled nuclear reactors is described. An electrical induction apparatus indicates the variation of magnetic coupling caused by a ferromagnetic member of the apparatus being subjected to such strains. (U.K.)

  18. Photoacoustic temperature measurements for monitoring of thermal therapy

    Science.gov (United States)

    Wang, Shiou-Han; Wei, Chen-Wei; Jee, Shiou-Hwa; Li, Pai-Chi

    2009-02-01

    Plasmonic photothermal therapy is a new cancer thermotherapy method based on surface plasmon resonance of nanoparticles. It is important to measure the temperature during thermotherapy for safety and efficacy. In this study, we apply a photoacoustic (PA) method for real-time, non-invasive temperature measurements. In particular, this method can be effectively combined with a photothermal therapy system that we developed in parallel. The method is based on the fact that the PA pressure amplitude is linearly related to temperature. To explore its potential, a home-made, 20 MHz PA transducer was used, in which an optical fiber was inserted in its center for emitting laser pulses while the PA signal was simultaneously detected. Continuous wave (CW) laser was used to heat the subject, including both phantoms and mice. The temperature of the region of interest was also measured by a fine-needle thermal couple. Results show that the temperature was linearly proportional to the PA signal with good correlation with the CW laser irradiation. The in vivo study also demonstrated potential of this technique.

  19. High-temperature complementary metal oxide semiconductors (CMOS)

    International Nuclear Information System (INIS)

    McBrayer, J.D.

    1979-10-01

    Silicon CMOS devices were studied, tested, and evaluated at high temperatures to determine processing, geometric, operating characteristics, and stability parameters. After more than 1000 hours at 300 0 C, most devices showed good stability, reliability, and operating characteristics. Processing and geometric parameters were evaluated and optimization steps discussed

  20. High-temperature complementary metal oxide semiconductors (CMOS)

    Energy Technology Data Exchange (ETDEWEB)

    McBrayer, J.D.

    1979-10-01

    Silicon CMOS devices were studied, tested, and evaluated at high temperatures to determine processing, geometric, operating characteristics, and stability parameters. After more than 1000 hours at 300/sup 0/C, most devices showed good stability, reliability, and operating characteristics. Processing and geometric parameters were evaluated and optimization steps discussed.

  1. Surface Intermediates on Metal Electrodes at High Temperature

    DEFF Research Database (Denmark)

    Zachau-Christiansen, Birgit; Jacobsen, Torben; Bay, Lasse

    1997-01-01

    The mechanisms widely suggested for the O2-reduc-tion or H2-oxidation SOFC reactions involve inter-mediate O/H species adsorbed on the electrode surface. The presence of these intermediates is investigated by linear sweep voltammetry. In airat moderate temperatures (500øC) Pt in contact with YSZ...

  2. National Coral Reef Monitoring Program: Water Temperature Data from Subsurface Temperature Recorders (STRs) deployed at coral reef sites in the Hawaiian Archipelago from 2010 to 2016

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water temperature data are collected using subsurface temperature recorders (STRs) that aid in the monitoring of seawater temperature variability at permanent coral...

  3. National Coral Reef Monitoring Program: Water Temperature Data from Subsurface Temperature Recorders (STRs) deployed at coral reef sites in the Pacific Remote Island Areas from 2011 to 2016

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water temperature data are collected using subsurface temperature recorders (STRs) that aid in the monitoring of seawater temperature variability at permanent coral...

  4. National Coral Reef Monitoring Program: Water Temperature Data from Subsurface Temperature Recorders (STRs) deployed at coral reef sites in American Samoa from 2012 to 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water temperature data are collected using subsurface temperature recorders (STRs) that aid in the monitoring of seawater temperature variability at permanent coral...

  5. National Coral Reef Monitoring Program: Water Temperature Data from Subsurface Temperature Recorders (STRs) deployed at coral reef sites in the Marianas Archipelago from 2011 to 2014

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water temperature data are collected using subsurface temperature recorders (STRs) that aid in the monitoring of seawater temperature variability at permanent coral...

  6. Optical Fiber Strain Instrumentation for High Temperature Aerospace Structural Monitoring

    Science.gov (United States)

    Wang, A.

    2002-01-01

    The objective of the program is the development and laboratory demonstration of sensors based on silica optical fibers for measurement of high temperature strain for aerospace materials evaluations. A complete fiber strain sensor system based on white-light interferometry was designed and implemented. An experiment set-up was constructed to permit testing of strain measurement up to 850 C. The strain is created by bending an alumina cantilever beam to which is the fiber sensor is attached. The strain calibration is provided by the application of known beam deflections. To ensure the high temperature operation capability of the sensor, gold-coated single-mode fiber is used. Moreover, a new method of sensor surface attachment which permits accurate sensor gage length determination is also developed. Excellent results were obtained at temperatures up to 800-850 C.

  7. Regulatory quality control in the metal and semi metal environmental monitoring program at IPEN/CNEN-SP

    Energy Technology Data Exchange (ETDEWEB)

    Faustino, Mainara G.; Silva, Doulgas Batista; Monteiro, Lucilena R.; Dantas, Elizabeth S.K.; Pires, Maria Aparecida F.; Cotrim, Marycel E.B., E-mail: lrmonteiro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The CONAMA's Resolution 430 recently published in May 13{sup th} of 2011, that completes and modifies the Resolution 357/2005, defined new quality standards to perform liquid effluent monitoring essays in order to allow the release in the public sewer system. This Resolution has established that the essay laboratories must be certified by Brazilian National Metrology, Normalization and Industrial Quality Institute - INMETRO and also count with an implemented quality control system. Thereby this publication affected directly IPEN's Environmental Monitoring Program of Stables Chemical Compound (PMA-Q), performed since 2007. In this program, 20 parameters related to the metallic and non-metallic chemical elements content are monitored by using sensitive analytical techniques such as graphite furnace atomic absorption spectrometry - GF-AAS or inductively coupled plasma spectrometry - ICP-OES. Therefore this paper presents improvements to determine the laboratory individual performance performed by GF-AAS and ICP-OES. To achieve the legislation compliance for these parameters, the following actions were implemented: the construction of control charts (internal quality control) and the participation of the laboratory in interlaboratory proficiency tests (external quality control). These actions are presented and discussed with the results of elements such as Arsenic and Lead that are analyzed through GF-AAS as well as Chromium, Cooper, Zinc, Iron and Nickel, that are analyzed through ICP-OES. These actions of quality control allowed the continuous monitoring of laboratory performance, the identification and resolution of analytic problems and interlaboratory differences, provide additional confidence to monitoring program. (author)

  8. Monitoring of streams: macrozoobenthos and accumulation of heavy metals and radionuclides in bottom sediments

    International Nuclear Information System (INIS)

    Arbaciauskas, K.; Mackeviciene, G.; Striupkuviene, N.; Motiejunas, S; Kreslauskaite, R.

    1998-01-01

    To evaluate the environmental quality of streams in integrated monitoring sites (IMS) and agrostations (AS), the macrozoobenthos communities and accumulation of heavy metals and radionuclides in bottom sediments were studied during 1993-1996. Samples of macrozoobenthos were collected in stream biotopes which were recommended for monitoring. Community biodiversity was assessed by Shannon-Wiener and Simpson indices, and water quality of streams was estimated by Trent and Mean Chandler biotic indices. Heavy metal (Pb, Cd, Cu, Cr, Ni, Mn) concentrations and radionuclide ( 137 Cs, 134 Cs, 40 K, 90 Sr) activity were determined in sediments. Macrozoobenthos communities indicated that the studied streams were clean waters. The heavy metal concentrations in surficial sediments showed annual and seasonal changes and differences between monitoring sites. The Cu concentration in the soft turfy stream sediments at the Aukstaitija IMS was twice as high as that in sediments of other monitoring streams with hard sandy-gravel bottoms. During 1994-1996, the Ni concentration decreased, while levels of Cu, Cd and Cr were relatively stable. The Pb concentrations decreased in all IMS, while those in AS increased. The concentration of 137 Cs was relatively stable in agrostation streams. Compared to levels in 1993, an increase of 137 Cs activity was observed in sediments at the Dzuklija IMS during 1995-1996. 90 Sr activity fluctuated in the monitoring sites from 1.6 to 3.7 Bq/kg dry weight. (author)

  9. Low-temperature embrittlement and fracture of metals with different crystal lattices – Dislocation mechanisms

    Directory of Open Access Journals (Sweden)

    V.M. Chernov

    2016-12-01

    Full Text Available The state of a low-temperature embrittlement (cold brittleness and dislocation mechanisms for formation of the temperature of a ductile-brittle transition and brittle fracture of metals (mono- and polycrystals with various crystal lattices (BCC, FCC, HCP are considered. The conditions for their formation connected with a stress-deformed state and strength (low temperature yield strength as well as the fracture breaking stress and mobility of dislocations in the top of a crack of the fractured metal are determined. These conditions can be met for BCC and some HCP metals in the initial state (without irradiation and after a low-temperature damaging (neutron irradiation. These conditions are not met for FCC and many HCP metals. In the process of the damaging (neutron irradiation such conditions are not met also and the state of low-temperature embrittlement of metals is absent (suppressed due to arising various radiation dynamic processes, which increase the mobility of dislocations and worsen the strength characteristics.

  10. On the use of temperature for online condition monitoring of geared systems - A review

    Science.gov (United States)

    Touret, T.; Changenet, C.; Ville, F.; Lalmi, M.; Becquerelle, S.

    2018-02-01

    Gear unit condition monitoring is a key factor for mechanical system reliability management. When they are subjected to failure, gears and bearings may generate excessive vibration, debris and heat. Vibratory, acoustic or debris analyses are proven approaches to perform condition monitoring. An alternative to those methods is to use temperature as a condition indicator to detect gearbox failure. The review focuses on condition monitoring studies which use this thermal approach. According to the failure type and the measurement method, it exists a distinction whether it is contact (e.g. thermocouple) or non-contact temperature sensor (e.g. thermography). Capabilities and limitations of this approach are discussed. It is shown that the use of temperature for condition monitoring has a clear potential as an alternative to vibratory or acoustic health monitoring.

  11. Nanofluid based on self-nanoencapsulated metal/metal alloys phase change materials with tuneable crystallisation temperature.

    Science.gov (United States)

    Navarrete, Nuria; Gimeno-Furio, Alexandra; Mondragon, Rosa; Hernandez, Leonor; Cabedo, Luis; Cordoncillo, Eloisa; Julia, J Enrique

    2017-12-14

    Nanofluids using nanoencapsulated Phase Change Materials (nePCM) allow increments in both the thermal conductivity and heat capacity of the base fluid. Incremented heat capacity is produced by the melting enthalpy of the nanoparticles core. In this work two important advances in this nanofluid type are proposed and experimentally tested. It is firstly shown that metal and metal alloy nanoparticles can be used as self-encapsulated nePCM using the metal oxide layer that forms naturally in most commercial synthesis processes as encapsulation. In line with this, Sn/SnOx nanoparticles morphology, size and thermal properties were studied by testing the suitability and performance of encapsulation at high temperatures and thermal cycling using a commercial thermal oil (Therminol 66) as the base fluid. Secondly, a mechanism to control the supercooling effect of this nePCM type based on non-eutectic alloys was developed.

  12. Electronic Tongue-FIA system for the Monitoring of Heavy Metal Biosorption Processes

    Science.gov (United States)

    Wilson, D.; Florido, A.; Valderrama, C.; de Labastida, M. Fernández; Alegret, S.; del Valle, M.

    2011-09-01

    An automated flow injection potentiometric (FIP) system with electronic tongue detection (ET) was used for the monitoring of biosorption processes of heavy metals on waste biomaterial. Grape stalk wastes were used as biosorbent to remove Cu2+ ions in a fixed-bed column setup. For the monitoring, the used ET employed a sensor array formed by Cu2+ and Ca2+ selective electrodes and two generic heavy-metal electrodes. The subsequent cross-response obtained was processed by a multilayer artificial neural network (ANN) model in order to resolve the concentrations of the monitored species. The coupling of the electronic tongue with the automation features of the flow-injection system (ET-FIP) allowed us to accurately characterize the biosorption process, through obtaining its breakthrough curves. In parallel, fractions of the extract solution were analyzed by atomic absorption spectroscopy in order to validate the results obtained with the reported methodology.

  13. In-Situ Real-Time Temperature Monitoring of Thermal Protection Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This program addresses the need for interfacial and in-depth temperature monitoring of thermal protection systems (TPS). Novel, linear drive, eddy current methods...

  14. In-Situ Real-Time Temperature Monitoring of Thermal Protection Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This program addresses the need for interfacial and in-depth temperature monitoring of thermal protection systems (TPS). Novel, linear drive, eddy current methods...

  15. Fish product quality evaluation based on temperature monitoring in ...

    African Journals Online (AJOL)

    Yomi

    2010-09-13

    Sep 13, 2010 ... Key words: Frozen tilapia fillet, temperature, cold chain, shelf-life, total volatile base-nitrogen, sensory ... and use value was seriously affected. The cold chain management (CCM) has become crucial, challenging and important to keep fish product safety due to a .... Quality evaluation and Shelf-life modeling.

  16. TEMPERATURE DISTRIBUTION MONITORING AND ANALYSES AT DIFFERENT HEATING CONTROL PRINCIPLES

    DEFF Research Database (Denmark)

    Simone, Angela; Rode, Carsten; Olesen, Bjarne W.

    2010-01-01

    under different control strategies of the heating system (Pseudo Random Binary Sequence signal controlling all the heaters (PRBS) or thermostatic control of the heaters (THERM)). A comparison of the measured temperatures within the room, for the five series of experiments, shows a better correlation...

  17. Design and Development of a PC- Based temperature monitoring ...

    African Journals Online (AJOL)

    The design of the work involves a circuit that measures the surrounding temperature using appropriate sensors and the sensor output is then converted to digital signals after due processing and conditioning of the signals. There is also an interface circuit configured to make it compatible with the PC hardware. This design ...

  18. Low temperature isotope effects of hydrogen diffusion in metallic glasses

    International Nuclear Information System (INIS)

    Hofmann, A.; Kronmueller, H.

    1989-01-01

    Snoek-like relaxation peaks of Hydrogen and Deuterium in amorphous Fe 80 B 20 , Fe 40 Ni 40 P 14 B 6 and Fe 91 Zr 9 are detected. At low H, D concentrations the peaks are near 200 K and show small isotope effects of the average activation energies (anti Q H ≅ 0.6 eV, anti Q D - anti Q H ≤ 10 meV). For higher H, D-contents the peaks shift to lower temperatures around to 120 K and show distinct isotope effects in the activation energies (anti Q H ≅ 0.3 eV, anti Q D - anti Q H ≅ 30 meV) and in the amplitude of the low temperature tails of the relaxation peaks. This points to isotope mass dependent deviations from the Arrhenius law due to nonthermal tunneling processes. (orig.)

  19. Temperature-dependent chemical changes of metallic fuel

    Energy Technology Data Exchange (ETDEWEB)

    Youn, Young Sang; Lee, Jeong Mook; KimJong Hwan; Song, Hoon; Kim, Jong Yun [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    We observed the temperature-dependent variations of UZr alloy using surface analysis techniques such as X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, X-ray diffraction (XRD), and scanning electron microscope (SEM) equipped with energy-dispersive Xray spectroscope (EDS). In this work, we exhibited the results of XPS, Raman, XRD, and SEM-EDS for U-10wt%Zr alloy at room temperature, 610 and 1130 .deg. C. In SEM-EDS data, we observed that uranium and zirconium elements uniformly exist. After the annealing of U-10Zr sample at 1130 .deg. C, the formation of zirconium carbide is verified through Raman spectroscopy and XRD results. Additionally, the change of valence state for uranium element is also confirmed by XPS analysis.

  20. Measuring the temperature history of isochorically heated warm dense metals

    Science.gov (United States)

    McGuffey, Chris; Kim, J.; Park, J.; Moody, J.; Emig, J.; Heeter, B.; Dozieres, M.; Beg, Fn; McLean, Hs

    2017-10-01

    A pump-probe platform has been designed for soft X-ray absorption spectroscopy near edge structure measurements in isochorically heated Al or Cu samples with temperature of 10s to 100s of eV. The method is compatible with dual picosecond-class laser systems and may be used to measure the temperature of the sample heated directly by the pump laser or by a laser-driven proton beam Knowledge of the temperature history of warm dense samples will aid equation of state measurements. First, various low- to mid-Z targets were evaluated for their suitability as continuum X-ray backlighters over the range 200-1800 eV using a 10 J picosecond-class laser with relativistic peak intensity Alloys were found to be more suitable than single-element backlighters. Second, the heated sample package was designed with consideration of target thickness and tamp layers using atomic physics codes. The results of the first demonstration attempts will be presented. This work was supported by the U.S. DOE under Contract No. DE-SC0014600.

  1. K-band spectroscopic metallicities and temperatures of M-dwarf stars

    Directory of Open Access Journals (Sweden)

    Rojas-Ayala Bárbara

    2013-04-01

    Full Text Available I present the metallicity and effective temperature techniques developed for M dwarf stars by Rojas-Ayala et al. (2010, 2012. These techniques are based on absorption features present in the modest resolution K-band spectra (R∼2700 of M dwarfs and have been calibrated using FGK+M dwarf pairs and synthetic atmosphere models. The H2O-K2 index seems to overestimate the effective temperatures of M dwarfs when compared to interferometric measurements. The metallicity distribution of the M dwarf host candidates by the Kepler Mission hints that jovian-size planets form preferentially around solar and super-solar metallicity environments, while small rocky planet host exhibit a wide range of metallicities, just like in their solar-type counterparts.

  2. Physical defect formation in few layer graphene-like carbon on metals: influence of temperature, acidity, and chemical functionalization.

    Science.gov (United States)

    Schumacher, Christoph M; Grass, Robert N; Rossier, Michael; Athanassiou, Evagelos K; Stark, Wendelin J

    2012-03-06

    A systematical examination of the chemical stability of cobalt metal nanomagnets with a graphene-like carbon coating is used to study the otherwise rather elusive formation of nanometer-sized physical defects in few layer graphene as a result of acid treatments. We therefore first exposed the core-shell nanomaterial to well-controlled solutions of altering acidity and temperature. The release of cobalt into these solutions over time offered a simple tool to monitor the progress of particle degradation. The results suggested that the oxidative damage of the graphene-like coatings was the rate-limiting step during particle degradation since only fully intact or entirely emptied carbon shells were found after the experiments. If ionic noble metal species were additionally present in the acidic solutions, the noble metal was found to reduce on the surface of specific, defective particles. The altered electrochemical gradients across the carbon shells were however not found to lead to a faster release of cobalt from the particles. The suggested mechanistic insight was further confirmed by the covalent chemical functionalization of the particle surface with chemically inert aryl species, which leads to an additional thickening of the shells. This leads to reduced cobalt release rates as well as slower noble metal reduction rates depending on the augmentation of the shell thickness.

  3. SCUBA divers as oceanographic samplers: The potential of dive computers to augment aquatic temperature monitoring

    Science.gov (United States)

    Wright, Serena; Hull, Tom; Sivyer, David B.; Pearce, David; Pinnegar, John K.; Sayer, Martin D. J.; Mogg, Andrew O. M.; Azzopardi, Elaine; Gontarek, Steve; Hyder, Kieran

    2016-01-01

    Monitoring temperature of aquatic waters is of great importance, with modelled, satellite and in-situ data providing invaluable insights into long-term environmental change. However, there is often a lack of depth-resolved temperature measurements. Recreational dive computers routinely record temperature and depth, so could provide an alternate and highly novel source of oceanographic information to fill this data gap. In this study, a citizen science approach was used to obtain over 7,000 scuba diver temperature profiles. The accuracy, offset and lag of temperature records was assessed by comparing dive computers with scientific conductivity-temperature-depth instruments and existing surface temperature data. Our results show that, with processing, dive computers can provide a useful and novel tool with which to augment existing monitoring systems all over the globe, but especially in under-sampled or highly changeable coastal environments. PMID:27445104

  4. Temperature and field dependent Mossbauer studies of the metallic inclusions in synthetic MDAS diamond grits

    DEFF Research Database (Denmark)

    Bharuth-Ram, K.; Hansen, Mikkel Fougt; Mørup, Steen

    2001-01-01

    at temperatures of 300 K and 80 K, in zero field and in an external field of 0.60 T, on the metallic inclusions in these grits. The Mossbauer spectra of the inclusions are rather complex, reflecting the contributions of several different magnetic phases. Our results show that the temperature variation......Mossbauer spectroscopy of the metallic inclusions in diamond grits produced in high-temperature high-pressure synthesis have revealed varying but interesting results. The MDAS(1) grits synthesized with Fe/Ni solvent-catalysts show Mossbauer spectra that vary with grit size, with the ferromagnetic...... of the Mossbauer spectra is not due to superparamagnetic relaxation of ferromagnetic inclusions but rather to magnetic ordering temperatures of the order of room temperature. Based on the spectral lineshapes and elemental analyses, we suggest the inclusions in the 63-75 mum grits contain iron mainly in Fe...

  5. A temperature monitor circuit with small voltage sensitivity using a topology-reconfigurable ring oscillator

    Science.gov (United States)

    Kishimoto, Tadashi; Ishihara, Tohru; Onodera, Hidetoshi

    2018-04-01

    In this paper, we propose a temperature monitor circuit that exhibits a small supply voltage sensitivity adopting a circuit topology of a reconfigurable ring oscillator. The circuit topology of the monitor is crafted such that the oscillation frequency is determined by the amount of subthreshold leakage current, which has an exponential dependence on temperature. Another important characteristic of the monitor is its small supply voltage sensitivity. The measured oscillation frequency of a test chip fabricated in a 65 nm CMOS process varies only 2.6% under a wide range of supply voltages from 0.4 to 1.0 V at room temperature. The temperature estimation error ranges from ‑0.3 to 0.4 °C over a temperature range of 10 to 100 °C.

  6. Electronic Monitoring Of Storage And Transport Temperatures Of ...

    African Journals Online (AJOL)

    change in locations, type of carriage and storage. The data logger was sent back after the vaccination campaign and data were retrieved using a Tinytag Explorer software. The results showed that I-2 vaccine was stored and transported in temperatures within the range of 1.06ºC to 28.77ºC (average17.50ºC). The storage ...

  7. Effects of holding pressure and process temperatures on the mechanical properties of moulded metallic parts

    DEFF Research Database (Denmark)

    Islam, Aminul; Hansen, Hans Nørgaard; Esteves, N.M.

    2013-01-01

    Metal injection moulding is gaining more and more importance over the time and needs more research to be done to understand the sensitivity of process to different process parameters. The current paper makes an attempt to better understand the effects of holding pressure and process temperatures...... on the moulded metallic parts. Stainless steel 316L is used in the investigation to produce the specimen by metal injection moulding (MIM) and multiple analyses were carried out on samples produced with different combinations of holding pressure, mould temperature and melt temperature. Finally, the parts were...... characterized to investigate mechanical properties like density, ultimate tensile strength, shrinkage etc. The results are discussed in the paper. The main conclusion from this study is unlike plastic moulding, the tensile properties of MIM parts doesn’t vary based on the flow direction of the melt, and tensile...

  8. Cubic MnSb: Epitaxial growth of a predicted room temperature half-metal

    Science.gov (United States)

    Aldous, James D.; Burrows, Christopher W.; Sánchez, Ana M.; Beanland, Richard; Maskery, Ian; Bradley, Matthew K.; Dos Santos Dias, Manuel; Staunton, Julie B.; Bell, Gavin R.

    2012-02-01

    Epitaxial films including bulklike cubic and wurtzite polymorphs of MnSb have been grown by molecular beam epitaxy on GaAs via careful control of the Sb4/Mn flux ratio. Nonzero-temperature density functional theory was used to predict ab initio the half-metallicity of the cubic polymorph and compare its spin polarization as a function of reduced magnetization with that of the well known half-metal NiMnSb. In both cases, half-metallicity is lost at a threshold magnetization reduction, corresponding to a temperature T*350 K, making epitaxial cubic MnSb a promising candidate for efficient room temperature spin injection into semiconductors.

  9. Gallium-Based Room-Temperature Liquid Metals: Actuation and Manipulation of Droplets and Flows

    Directory of Open Access Journals (Sweden)

    Leily Majidi

    2017-08-01

    Full Text Available Gallium-based room-temperature liquid metals possess extremely valuable properties, such as low toxicity, low vapor pressure, and high thermal and electrical conductivity enabling them to become suitable substitutes for mercury and beyond in wide range of applications. When exposed to air, a native oxide layer forms on the surface of gallium-based liquid metals which mechanically stabilizes the liquid. By removing or reconstructing the oxide skin, shape and state of liquid metal droplets and flows can be manipulated/actuated desirably. This can occur manually or in the presence/absence of a magnetic/electric field. These methods lead to numerous useful applications such as soft electronics, reconfigurable devices, and soft robots. In this mini-review, we summarize the most recent progresses achieved on liquid metal droplet generation and actuation of gallium-based liquid metals with/without an external force.

  10. Amine promoted, metal enhanced degradation of Mirex under high temperature conditions

    International Nuclear Information System (INIS)

    Jallad, Karim N.; Lynn, Bert C.; Alley, Earl G.

    2006-01-01

    In this study, zero-valent metal dehalogenation of mirex was conducted with amine solvents at high temperatures. Mirex was treated with excess amine in sealed glass tube reactors under nitrogen. The amines used were n-butyl amine (l), ethyl amine (l), dimethyl amine (g), diethyl amine (l), triethyl amine (l), trimethyl amine (g) and ammonia (g). The metals used were copper, zinc, magnesium, aluminum and calcium. The most suitable amine solvent and metal were selected by running a series of reactions with different amines and different zero-valent metals, in order to optimize the conditions under which complete degradation of mirex takes place. These dehalogenation reactions illustrated the role of zero-valent metals as reductants, whereas the amine solvents acted as proton donors. In this study, we report that mirex was completely degraded with diethyl amine (l) in the presence of copper at 100 deg. C and the hydrogenated products accounted for more than 94 of the degraded mirex

  11. Metal-Hydrogen Phase Diagrams in the Vicinity of Melting Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Shapovalov, V.I.

    1999-01-06

    Hydrogen-metal interaction phenomena belong to the most exciting challenges of today's physical metallurgy and physics of solids due to the uncommon behavior of hydrogen in condensed media and to the need for understanding hydrogen's strong negative impact on properties of some high-strength steels and.alloys. The paper cites and summarizes research data on fundamental thermodynamic characteristics of hydrogen in some metals that absorb it endothermally at elevated temperatures. For a number of metal-hydrogen systems, information on some phase diagrams previously not available to the English-speaking scientific community is presented.

  12. Low temperature uniform plastic deformation of metallic glasses during elastic iteration

    International Nuclear Information System (INIS)

    Fujita, Takeshi; Wang Zheng; Liu Yanhui; Sheng, Howard; Wang Weihua; Chen Mingwei

    2012-01-01

    Molecular dynamics simulations and dynamic mechanical analysis experiments were employed to investigate the mechanical behavior of metallic glasses subjected to iteration deformation in a nominally elastic region. It was found that cyclic deformation leads to the formation of irreversible shear transformation zones (STZs) and a permanent uniform strain. The initiation of STZs is directly correlated with the atomic heterogeneity of the metallic glass and the accumulated permanent strain has a linear relation with the number of STZs. This study reveals a new deformation mode and offers insights into the atomic mechanisms of STZ formation and low temperature uniform plastic deformation of metallic glasses.

  13. Bonding glass to metal with plastic for stability over temperature

    Science.gov (United States)

    Willis, Chris L.; Petrie, Stephen P.

    2001-11-01

    To enable the invention of higher power IRCM lasers, 3D LIDAR systems, Designator/Rangefinders and other Instruments subjected to a broad range of operating conditions, there is a need to develop improved technology to hold small mirrors, lenses, beamsplitters and other optical elements with repeatable and high dimensional stability over wide environmental temperature ranges, an do so with great economy. The intent of this effort was to begin identifying significant factors for bonding small mirrors for high stability. A screening experiment was performed in which half-inch diameter flat mirrors were face bonded to similar mirror mounts, then bolted to a reference test fixture and subjected to an environmental temperature range of -40 to +70 degrees C. Mount material, optic material, adhesive material, bond joint design, and bond thickness were varied. The resulting tilt errors in the mirror assemblies were measured. Steps were taken to isolate the bond joint stability as opposed to stability in the mounted mirror subassemblies. The effort required to minimize experimental noise was much greater than anticipated. This first experimental effort failed to identify main factors with statistical significance, however; some results are interesting. Perhaps also of interest is the progress made at characterizing the experimental setup and process, and lessons learned in control of noise factors in this kind of experiment.

  14. Heavy metal monitoring, analysis and prediction in lakes and rivers: state of the art.

    Science.gov (United States)

    Elzwayie, Adnan; Afan, Haitham Abdulmohsin; Allawi, Mohammed Falah; El-Shafie, Ahmed

    2017-05-01

    Several research efforts have been conducted to monitor and analyze the impact of environmental factors on the heavy metal concentrations and physicochemical properties of water bodies (lakes and rivers) in different countries worldwide. This article provides a general overview of the previous works that have been completed in monitoring and analyzing heavy metals. The intention of this review is to introduce the historical studies to distinguish and understand the previous challenges faced by researchers in analyzing heavy metal accumulation. In addition, this review introduces a survey on the importance of time increment sampling (monthly and/or seasonally) to comprehend and determine the rate of change of different parameters on a monthly and seasonal basis. Furthermore, suggestions are made for future research to achieve more understandable figures on heavy metal accumulation by considering climate conditions. Thus, the intent of the current study is the provision of reliable models for predicting future heavy metal accumulation in water bodies in different climates and pollution conditions so that water management can be achieved using intelligent proactive strategies and artificial neural network (ANN) techniques.

  15. GMDH and neural networks applied in temperature sensors monitoring

    International Nuclear Information System (INIS)

    Bueno, Elaine Inacio; Pereira, Iraci Martinez; Silva, Antonio Teixeira e

    2009-01-01

    In this work a monitoring system was developed based on the Group Method of Data Handling (GMDH) and Neural Networks (ANNs) methodologies. This methodology was applied to the IEA-R1 research reactor at IPEN by using a database obtained from a theoretical model of the reactor. The IEA-R1 research reactor is a pool type reactor of 5 MW, cooled and moderated by light water, and uses graphite and beryllium as reflector. The theoretical model was developed using the Matlab GUIDE toolbox. The equations are based in the IEA-R1 mass and energy inventory balance and physical as well as operational aspects are taken into consideration. This methodology was developed by using the GMDH algorithm as input variables to the ANNs. The results obtained using the GMDH and ANNs were better than that obtained using only ANNs. (author)

  16. Decision support system for temperature monitoring in beehives

    Directory of Open Access Journals (Sweden)

    Marković Dušan

    2016-01-01

    Full Text Available European honeybee colonies are the most important pollinator insects and source of honey and other useful products. Honeybee colonies today face new diseases and pests as well as pollution which threaten their survival and endanger whole food production which relies on honey bee pollination. Internet of Things (IoT technology enables integration of wireless sensors inside beehives to enable remote monitoring of various beehive parameters from remote location using Internet. Detection of certain critical events in beehive is hard to be explicitly program due to complex dependence between multiple input parameters. Machine learning algorithms give computers the ability to learn to detect these events without being explicitly programmed. Detection of these event from streams of data collected from IoT sensors is possible using Complex Event Processing (CEP which applies machine induced knowledge do detect and warn beekeepers about certain events in beehive.

  17. Electromagnetic-acoustic coupling in ferromagnetic metals at liquid-helium temperatures

    DEFF Research Database (Denmark)

    Gordon, R A

    1981-01-01

    Electromagnetic-acoustic coupling at the surface and in the bulk of ferromagnetic metals at liquid-helium temperatures has been studied using electromagnetically excited acoustic standing-wave resonances at MHz frequencies in a number of ferromagnetic metals and alloys of commercial interest....... The experimental results are compared with similar measurements at room temperature in the same and in different samples as well as with existing theoretical descriptions of the phenomenon. Journal of Applied Physics is copyrighted by The American Institute of Physics....

  18. Hot metal temperature prediction in blast furnace using advanced model based on fuzzy logic tools

    Energy Technology Data Exchange (ETDEWEB)

    Martin, R.D.; Obeso, F.; Mochon, J.; Barea, R.; Jimenez, J.

    2007-05-15

    The present work presents a model based on fuzzy logic tools to predict and simulate the hot metal temperature in a blast furnace (BF). As input variables this model uses the control variables of a current BF such as moisture, pulverised coal injection, oxygen addition, mineral/coke ratio and blast volume, and it yields as a result of the hot metal temperature. The variables employed to develop the model have been obtained from data supplied by current sensors of a Spanish BF In the model training stage the adaptive neurofuzzy inference system and the subtractive clustering algorithms have been used.

  19. The temperature coefficient of the resonance integral for uranium metal and oxide

    International Nuclear Information System (INIS)

    Blomberg, P.; Hellstrand, E.; Homer, S.

    1960-06-01

    The temperature coefficient of the resonance integral in uranium metal and oxide has been measured over a wide temperature range for rods with three different diameters. The results for metal agree with most earlier results from activation measurements but differ as much as a factor of two from results obtained with reactivity methods. For oxide only one measurement has been reported recently. Our value is considerably lower than the result of that measurement. The experiments will continue in order to find the reason for the large discrepancy mentioned above

  20. A GSM-Based Remote Temperature and Humidity Monitoring System for Granary

    Directory of Open Access Journals (Sweden)

    Zheng Xiao Xi

    2016-01-01

    Full Text Available A remote temperature and humidity monitoring system is designed based on the GSM technology and MSP430. With the digital sensor DSB1820 and SHT11, the temperature and humidity of the granary are detected, and these parameters can be adjusted with the controlling system to adapt various working conditions. Through the GSM system, the detected data could be sent to various monitoring devices, such as cellphones and laptops. These data can be used for data display, inquiry, controlling and storage at the remote terminals. The experimental results show that the system is convenient and concise, which meets the remote monitoring demand for the modern granary.

  1. On the nature of low temperature anomalies of metallic glass inelastic properties

    International Nuclear Information System (INIS)

    Spivak, L.V.; Khonik, V.A.

    1997-01-01

    Low-temperature (30 60 Nb 40 metallic glass (MG) exposed to the preliminary cold deformation via rolling, to high-temperature homogeneous deformation or to electrolytic hydrogen absorption were investigated. Conclusion is made that the published low-temperature peaks of the internal friction in quick-hardened cold-deformed or hydrogen absorbed MGs are of the common dislocation-like nature. Effect of 2 MeV electron irradiation on the temperature dependence of the internal friction and on the elasticity module of hydrogenated specimens was investigated, as well [ru

  2. Monitoring and Modeling Temperature Variations Inside Silage Stack Using Novel Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Green, Ole; Shahrak Nadimi, Esmaeil; Blanes-Vidal, Victoria

    2009-01-01

    Abstract: By monitoring silage temperature at different locations inside silage stacks, it is possible to detect any significant increases in temperature occurring during silage decomposition. The objectives of this study were: (1) to develop novel noninvasive wireless sensor nodes for measuring ...

  3. Monitoring and modeling temperature variations inside silage stacks using novel wireless sensor networks

    DEFF Research Database (Denmark)

    Green, O.; Nadimi, E.S.; Blanes-Vidal, V.

    2009-01-01

    By monitoring silage temperature at different locations inside silage stacks, it is possible to detect any significant increases in temperature occurring during silage decomposition. The objectives of this study were: (1) to develop novel noninvasive wireless sensor nodes for measuring the temper...

  4. Chemical composition and effective temperatures of metallic line white dwarfs

    International Nuclear Information System (INIS)

    Hammond, G.L.

    1974-01-01

    Model atmosphere techniques have been employed to determine the composition, effective temperatures, radii, masses and surface gravities of white dwarfs Ross 640 and van Maanen 2. The non-gray, LTE, convective, constant flux models employed collisional damping constants for the Ca II H and K lines that were measured in a laboratory device that simulated white dwarf atmospheric conditions. Ross 640 was found to have an extremely helium-rich composition and T/sub eff/ = 8500K, while the observed properties of van Maanen 2 were fitted best by a model with 91 percent helium, 9 percent hydrogen and T/sub eff/ = 6100K. The laboratory measurements of pressure shifts for the Ca II lines casts some doubt on the interpretation of recent radial velocity determinations for van Maanen 2. (U.S.)

  5. Monitoring transport and equilibrium of heavy metals in soil using induced polarization

    Science.gov (United States)

    Shalem, T.; Huisman, J. A.; Zimmermann, E.; Furman, A.

    2017-12-01

    Soil and groundwater pollution in general, and by heavy metals in particular, is a major threat to human health, and especially in rapidly developing regions, such as China. Fast, accurate and low-cost measurement of heavy metal contamination is of high desire. Spectral induced polarization (SIP) may be an alternative to the tedious sampling techniques typically used. In the SIP method, an alternating current at a range of low frequencies is injected into the soil and the resultant potential is measured along the current's path. SIP is a promising method for monitoring heavy metals, because it is sensitive to the chemical composition of both the absorbed ions on the soil minerals and the pore fluid and to the interface between the two. The high sorption affinity of heavy metals suggests that their electrical signature may be significant, even at relatively low concentrations. The goal of this research is to examine the electrical signature of soil contaminated by heavy metals and of the pollution transport and remediation processes, in a non-tomographic fashion. Specifically, we are looking at the SIP response of various heavy metals in several settings: 1) at equilibrium state in batch experiments; 2) following the progress of a pollution front along a soil column through flow experiments and 3) monitoring the extraction of the contaminant by a chelating agent. Using the results, we develop and calibrate a multi-Cole-Cole model to separate the electrochemical and the interfacial components of the polarization. Last, we compare our results to the electrical signature of contaminated soil from southern China. Results of single metals from both batch and flow experiments display a shift of the relaxation time and a decrease in the phase response of the soil with increase of the metal concentration, suggesting strong sorption of the metals on the stern layer. Preliminary results also show evidence of electrodic polarization, assuming to be related to the formation of

  6. Pumping liquid metal at high temperatures up to 1,673 kelvin.

    Science.gov (United States)

    Amy, C; Budenstein, D; Bagepalli, M; England, D; DeAngelis, F; Wilk, G; Jarrett, C; Kelsall, C; Hirschey, J; Wen, H; Chavan, A; Gilleland, B; Yuan, C; Chueh, W C; Sandhage, K H; Kawajiri, Y; Henry, A

    2017-10-11

    Heat is fundamental to power generation and many industrial processes, and is most useful at high temperatures because it can be converted more efficiently to other types of energy. However, efficient transportation, storage and conversion of heat at extreme temperatures (more than about 1,300 kelvin) is impractical for many applications. Liquid metals can be very effective media for transferring heat at high temperatures, but liquid-metal pumping has been limited by the corrosion of metal infrastructures. Here we demonstrate a ceramic, mechanical pump that can be used to continuously circulate liquid tin at temperatures of around 1,473-1,673 kelvin. Our approach to liquid-metal pumping is enabled by the use of ceramics for the mechanical and sealing components, but owing to the brittle nature of ceramics their use requires careful engineering. Our set-up enables effective heat transfer using a liquid at previously unattainable temperatures, and could be used for thermal storage and transport, electric power production, and chemical or materials processing.

  7. Pumping liquid metal at high temperatures up to 1,673 kelvin

    Science.gov (United States)

    Amy, C.; Budenstein, D.; Bagepalli, M.; England, D.; Deangelis, F.; Wilk, G.; Jarrett, C.; Kelsall, C.; Hirschey, J.; Wen, H.; Chavan, A.; Gilleland, B.; Yuan, C.; Chueh, W. C.; Sandhage, K. H.; Kawajiri, Y.; Henry, A.

    2017-10-01

    Heat is fundamental to power generation and many industrial processes, and is most useful at high temperatures because it can be converted more efficiently to other types of energy. However, efficient transportation, storage and conversion of heat at extreme temperatures (more than about 1,300 kelvin) is impractical for many applications. Liquid metals can be very effective media for transferring heat at high temperatures, but liquid-metal pumping has been limited by the corrosion of metal infrastructures. Here we demonstrate a ceramic, mechanical pump that can be used to continuously circulate liquid tin at temperatures of around 1,473-1,673 kelvin. Our approach to liquid-metal pumping is enabled by the use of ceramics for the mechanical and sealing components, but owing to the brittle nature of ceramics their use requires careful engineering. Our set-up enables effective heat transfer using a liquid at previously unattainable temperatures, and could be used for thermal storage and transport, electric power production, and chemical or materials processing.

  8. Corrosion of metallic materials by uranium hexafluoride at high temperatures (1963)

    International Nuclear Information System (INIS)

    Langlois, G.

    1963-01-01

    The corrosion of the following metals or alloys by UF 6 : nickel, monel, Inconel, gold, platinum, stainless steel, is studied in the temperature range from 300 to 1000 deg. C. The test method, designed to avoid heating the apparatus containing the corrosive fluid to a high temperature, consists in using threadlike samples heated by the Joule effect, the rest of the apparatus being maintained close to room temperature. This technique makes it possible also to determine continuously the penetration of the corrosion by measuring the electrical resistance of the sample with a double Thomson bridge. A series of rapid comparison tests shows that stainless steel, precious metals and Inconel are attacked far too rapidly to be used above 500 deg. C; only monel and especially nickel appear capable of resisting at high temperatures. The detailed examination of the behaviour of nickel shows that the metallic fluoride is volatilized and that this influences the corrosion rate. It shows also the existence of a temperature zone situated between 550 and 700 deg. C in which occurs A strong intergranular corrosion the cause of which appears to be the presence of impurities in the metal. (author) [fr

  9. Standard Guide for Use of Melt Wire Temperature Monitors for Reactor Vessel Surveillance, E 706 (IIIE)

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 This guide describes the application of melt wire temperature monitors and their use for reactor vessel surveillance of light-water power reactors as called for in Practice E 185. 1.2 The purpose of this guide is to recommend the selection and use of the common melt wire technique where the correspondence between melting temperature and composition of different alloys is used as a passive temperature monitor. Guidelines are provided for the selection and calibration of monitor materials; design, fabrication, and assembly of monitor and container; post-irradiation examinations; interpretation of the results; and estimation of uncertainties. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. (See Note 1.)

  10. Low Temperature Metal Coating Method Final Report CRADA No. TSB-1155-95

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sang-Wook [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gabel, Howard [Innovative Technology, Inc., Santa Barbara, CA (United States)

    2018-01-19

    A new metal coating method, cidled KEM (kinetic energy metal.lization), demonstrated in the laboratory by lnovati, utilized fast-moving solid particIes entrained in a gas that are caused to fiow through a nozzIe to effect particle deposition on metal surfaces at room temperature conditions. This method (US Patent 5,795,626) was an attractive and viabIe alternative to the currentIy available high-temperature coating methods avaiIabIe. Since it differs significantly from existing metal coating technologies, a brief description of the method is incIuded here. The proposed method, KEM, achieves cohesive and adhesive metallurgical bonding through the high-speed coUision of powder with a substrate and the subsequent discharge of electrical charge at the substrate. Such coating is effected by entraining metal powder in a gas and accelerating this mixture through a supersonic nozzle. The gas/powder is directed towards the substrate to be coated. Collisions occur, initiaIly between the powder and the substrate, and, as the first Iayer of the coating forms, between the powder and the coating. During these collisions the powder is rapidly deformed, causing the exposure of fresh (oxide free) active metal surface. When these’active surfaces contact one another, they agglomerate and form true metaIIurgicaI bonds. The resultant coating has Iow porosity and high adhesive and cohesive strength. The formation of metaIIurgicaI bonds is potentiated by the discharge of electrical energy. This electrical energy is the result of triboeIectric charging of the particIes during acceleration and transit to the nozzIe. An advantage of the method is that it does not raise the temperature of the powder being appLiedor that of the substrate. Consequently, materials sensitive to high temperature may be applied without changing Me properties of the materkd or substrate.

  11. Instrumentation for core and coolant monitoring in liquid-metal fast breeder reactors (LMFBR)

    International Nuclear Information System (INIS)

    Hess, B.; Ruppert, E.

    1975-01-01

    The review on core and coolant instrumentation for liquid metal fast breeders aims to give a short survey of measurement methods and the variety of appropriate instrumentation developed and tested for reactor application throughout the world. The introductory part gives a general outline of instrumentation development, partly as the refinement of well-known thermal reactor instrumentation and partly as the special instrumentation demanded for LMFBR safety requirements, some aspects of which are also discussed briefly. The in-core LMFBR instrumentation is surveyed, classifying the measurement or monitoring of coolant properties such as temperature, pressure, flow and acoustic emission and the measurement of core-kinetic quantities such as neutron flux and reactivity. Without considering the fundamentals of the measurements, the state of instrument development is reviewed and, where known, future aspects are indicated. An additional review on fuel failure detection methods and the related instrumentation distinguishes between global or whole-core detection methods and those used for localization of failures. Special attention is paid to the aspect of reactor safety and its reliability as one of the major objectives of these detection methods. A summary of the protective systems and instrumentation already used or foreseen for LMFBR plants forms a transition to a very brief discussion of handling and interpretation of the multitude of data derived from the rather comprehensive LMFBR instrumentation. This state of the art review claims neither to be complete at the time published nor to be a detailed guide to special problems of instrumentation development, the solutions to which are normally part of industrial knowhow. (author)

  12. Monitoring Temperature in High Enthalpy Arc-heated Plasma Flows using Tunable Diode Laser Absorption Spectroscopy

    Science.gov (United States)

    Martin, Marcel Nations; Chang, Leyen S.; Jeffries, Jay B.; Hanson, Ronald K.; Nawaz, Anuscheh; Taunk, Jaswinder S.; Driver, David M.; Raiche, George

    2013-01-01

    A tunable diode laser sensor was designed for in situ monitoring of temperature in the arc heater of the NASA Ames IHF arcjet facility (60 MW). An external cavity diode laser was used to generate light at 777.2 nm and laser absorption used to monitor the population of electronically excited oxygen atoms in an air plasma flow. Under the assumption of thermochemical equilibrium, time-resolved temperature measurements were obtained on four lines-of-sight, which enabled evaluation of the temperature uniformity in the plasma column for different arcjet operating conditions.

  13. Monitoring of the temperature reactivity coefficient at the PWR nuclear plant

    International Nuclear Information System (INIS)

    Kostic, Lj.

    1996-01-01

    For monitoring temperature coefficient of reactivity of pressurized water reactor a method based on the correction of fluctuation in signals of i-core neutron detectors and core-exit thermocouples and neural network paradigm is used it is shown that the moderator temperature coefficient of relativity can be predicted with the aid of the back propagation neural network technique by measuring the frequency response function between the in-core neutron flux and the core-exit coolant temperature

  14. Low temperature irradiation effects on plastic deformation in BCC metals

    International Nuclear Information System (INIS)

    Aono, Yasuhisa

    1984-01-01

    Low temperature electron beam experiment was carried out on high purity iron and molybdenum single crystals, and its effect on the plastic deformation was examined. As the characteristics of the irradiated iron below 77 K, remarkable softening occurred in all orientations. This phenomenon is based on the interaction of self interstitial atoms and screw dislocations, and the other features such as the absorption of interstitial atoms into screw dislocations and the slip on maximum shearing stress planes were shown. On the other hand, the aggregate of interstitial atoms formed by annealing showed the different plastic characteristics from those of interstitial atoms, and gave the results corresponding to respective stages of the electric resistance recovery curves. Regarding molybdenum, the transfer of its self interstitial atoms is near 40 K, therefore at 77 K, cluster is formed, and it largely affects abnormal slip, which is one of the features of the plasticity of molybdenum. The peculiar dependence of the yield stress on the crystalline orientation was shown. The property of the interaction of the aggregate of interstitial atoms formed and grown by the annealing from 77 K to 500 K with dislocations corresponded to the information of defects obtained by the X-ray research of Maeta, and the similarity to the aggregate of iron was observed. (Kako, I.)

  15. The use of thermal imaging to monitoring skin temperature during cryotherapy: A systematic review

    Science.gov (United States)

    Matos, Filipe; Neves, Eduardo Borba; Norte, Marco; Rosa, Claudio; Reis, Victor Machado; Vilaça-Alves, José

    2015-11-01

    Cryotherapy has been applied on clinical injuries and as a method for exercise recovery. It is aimed to reduce edema, nervous conduction velocity, and tissue metabolism, as well as to accelerate the recovery process of the muscle injury induced by exercise. Objective: This review aim to investigate the applicability of thermal imaging as a method for monitoring skin temperature during cryotherapy. Method: Search the Web of Science database using the terms "Cryotherapy", "Thermography", "Thermal Image" and "Cooling". Results: Nineteen studies met the inclusion criteria and pass the PEDro scale quality evaluation. Evidence support the use of thermal imaging as a method for monitoring the skin temperature during cryotherapy, and it is superior to other contact methods and subjective methods of assessing skin temperature. Conclusion: Thermography seems to be an efficient, trustworthy and secure method in order to monitoring skin temperature during cryotherapy application. Evidence supports the use of thermography in detriment of contact methods as well as other subjective ones.

  16. The design of multi temperature and humidity monitoring system for incubator

    Science.gov (United States)

    Yu, Junyu; Xu, Peng; Peng, Zitao; Qiang, Haonan; Shen, Xiaoyan

    2017-01-01

    Currently, there is only one monitor of the temperature and humidity in an incubator, which may cause inaccurate or unreliable data, and even endanger the life safety of the baby. In order to solve this problem,we designed a multi-point temperature and humidity monitoring system for incubators. The system uses the STC12C5A60S2 microcontrollers as the sender core chip which is connected to four AM2321 temperature and humidity sensors. We select STM32F103ZET6 core development board as the receiving end,cooperating with Zigbee wireless transmitting and receiving module to realize data acquisition and transmission. This design can realize remote real-time observation data on the computer by communicating with PC via Ethernet. Prototype tests show that the system can effectively collect and display the information of temperature and humidity of multiple incubators at the same time and there are four monitors in each incubator.

  17. Ambient air monitoring for organic compounds, acids, and metals at Los Alamos National Laboratory, January 1991

    International Nuclear Information System (INIS)

    Williams, C.H.; Eberhart, C.F.

    1992-01-01

    Los Alamos National Laboratory (LANL) contracted Radian Corporation (Radian) to conduct a short-term, intensive air monitoring program whose goal was to estimate the impact of chemical emissions from LANL on the ambient air environment. A comprehensive emission inventory had identified more than 600 potential air contaminants in LANL's emissions. A subset of specific target chemicals was selected for monitoring: 20 organic vapors, 6 metals and 5 inorganic acid vapors. These were measured at 5 ground level sampling sites around LANL over seven consecutive days in January 1991. The sampling and analytical strategy used a combination of EPA and NIOSH methods modified for ambient air applications

  18. Liquid metals surface temperature fields measurements with a two-colour pyrometer

    OpenAIRE

    Monier, Romain; Thumerel, François; Chapuis, Julien; Soulié, Fabien; Bordreuil, Cyril

    2017-01-01

    International audience; The paper presents an apparatus to measure surface temperature distribution of liquid metals during fusion processes. The apparatus is based on dual wavelength radiation thermometry and is designed to measure temperature from 1500 to 3000 K. The pyrometer is based on standard optical parts and industrial CCD cameras. Uncertainties are analysed on the base of the radiometric equations. To insure relative precision in the measurement, a calibration procedure is conducted...

  19. The Interchangeability of Plasma and Whole Blood Metal Ion Measurement in the Monitoring of Metal on Metal Hips

    OpenAIRE

    Malek, Ibrahim A.; Rogers, Joanne; King, Amanda Christina; Clutton, Juliet; Winson, Daniel; John, Alun

    2015-01-01

    One hundred and twenty six paired samples of plasma and whole blood were measured with inductively coupled plasma mass spectrometry technique for metal ions analysis to determine a relationship between them. There was a significant difference between the mean plasma and whole blood concentrations of both cobalt (Co) and chromium (Cr) (p < 0.0001 for both Co and Cr). The mean ratio between plasma and whole blood Cr and Co was 1.56 (range: 0.39?3.85) and 1.54 (range: 0.64?18.26), respectively, ...

  20. Low-Temperature UV-Assisted Fabrication of Metal Oxide Thin Film Transistor

    Science.gov (United States)

    Zhu, Shuanglin

    Solution processed metal oxide semiconductors have attracted intensive attention in the last several decades and have emerged as a promising candidate for the application of thin film transistor (TFT) due to their nature of transparency, flexibility, high mobility, simple processing technique and potential low manufacturing cost. However, metal oxide thin film fabricated by solution process usually requires a high temperature (over 300 °C), which is above the glass transition temperature of some conventional polymer substrates. In order to fabricate the flexible electronic device on polymer substrates, it is necessary to find a facile approach to lower the fabrication temperature and minimize defects in metal oxide thin film. In this thesis, the electrical properties dependency on temperature is discussed and an UV-assisted annealing method incorporating Deep ultraviolet (DUV)-decomposable additives is demonstrated, which can effectively improve electrical properties solution processed metal oxide semiconductors processed at temperature as low as 220 °C. By studying a widely used indium oxide (In2O3) TFT as a model system, it is worth noted that compared with the sample without UV treatment, the linear mobility and saturation mobility of UV-annealing sample are improved by 56% and 40% respectively. Meanwhile, the subthreshold swing is decreased by 32%, indicating UV-treated device could turn on and off more efficiently. In addition to pure In2O3 film, the similar phenomena have also been observed in indium oxide based Indium-Gallium-Zinc Oxide (IGZO) system. These finding presented in this thesis suggest that the UV assisted annealing process open a new route to fabricate high performance metal oxide semiconductors under low temperatures.

  1. High-Temperature Solid Lubricant Coating by Plasma Spraying Using Metal-Metal Clad Powders

    Science.gov (United States)

    Zhang, Tiantian; Lan, Hao; Yu, Shouquan; Huang, Chuanbing; Du, Lingzhong; Zhang, Weigang

    2017-08-01

    NiCr/Ag-Mo composite coating was fabricated by atmospheric plasma spray technology using clad powders as the feedstock. Its tribological properties at variable temperature were evaluated using a ball-on-disk high-temperature tribometer in air. The results showed that compared with NiCr, the NiCr/Ag-Mo composite coating exhibited better lubrication effect and higher wear resistance at all test temperatures, especially above 600 °C. At 800 °C, NiCr/Ag-Mo composite coating showed the lowest friction coefficient of about 0.2 and its corresponding wear rate reached 2.5 × 10-5 mm3/Nm. Characterizations of NiCr/Ag-Mo composite coating revealed that at temperatures below 400 °C, Ag was smeared and spread onto the wear surface, reducing the friction and wear. At temperature above 500 °C, the Ag2MoO4 lubrication film formed by tribo-oxidation significantly improved the coating's lubrication effect and wear resistance.

  2. Temperature-dependent transport properties of graphene decorated by alkali metal adatoms (Li, K)

    Science.gov (United States)

    Woo, S.; Hemmatiyan, S.; Morrison, T. D.; Rathnayaka, K. D. D.; Lyuksyutov, I. F.; Naugle, D. G.

    2017-12-01

    We report the electrical transport properties of graphene for dilute alkali metal decoration (n ˜ 2 × 1012 cm-2) at cryogenic temperatures. Upon deposition of K and Li atoms at T = 20 K, graphene devices are doped with electrons, and the charge carrier mobility is decreased. As temperature is increased, the number of electrons donated to the graphene and the number of charged scatterers are reduced, and the mobility of the metal decorated graphene is increased. This differs from the typical temperature-dependent transport in undecorated graphene, where the mobility decreases with increasing temperature. To investigate the kinetic behavior of adatoms on graphene, we estimate the hopping time of the Li and K adatoms on graphene based on the migration barrier in the low concentration regime of the metal adatoms by Density Functional Theory calculations. The calculations reveal that these adatoms are mobile even at cryogenic temperatures and become more mobile with increasing temperature, allowing for cluster formation of adatoms. This indicates that the dominant factor in the electron transport on warming is a cluster formation.

  3. Metal-Controlled Magnetoresistance at Room Temperature in Single-Molecule Devices.

    Science.gov (United States)

    Aragonès, Albert C; Aravena, Daniel; Valverde-Muñoz, Francisco J; Real, José Antonio; Sanz, Fausto; Díez-Pérez, Ismael; Ruiz, Eliseo

    2017-04-26

    The appropriate choice of the transition metal complex and metal surface electronic structure opens the possibility to control the spin of the charge carriers through the resulting hybrid molecule/metal spinterface in a single-molecule electrical contact at room temperature. The single-molecule conductance of a Au/molecule/Ni junction can be switched by flipping the magnetization direction of the ferromagnetic electrode. The requirements of the molecule include not just the presence of unpaired electrons: the electronic configuration of the metal center has to provide occupied or empty orbitals that strongly interact with the junction metal electrodes and that are close in energy to their Fermi levels for one of the electronic spins only. The key ingredient for the metal surface is to provide an efficient spin texture induced by the spin-orbit coupling in the topological surface states that results in an efficient spin-dependent interaction with the orbitals of the molecule. The strong magnetoresistance effect found in this kind of single-molecule wire opens a new approach for the design of room-temperature nanoscale devices based on spin-polarized currents controlled at molecular level.

  4. Monitoring of airborne metal pollution by moss bags: a methodological study

    OpenAIRE

    Castello, Miris

    2017-01-01

    The use of moss transplants for monitoring heavy metals deposition is briefly reviewed. The methodological study concerns the effects of different types of pre-treatment on data variability. Epiphytic samples of Hypnum cupressiforme were collected from an unpolluted area, treated in different ways, and the resulting bags were exposed in two sites in the province of Trieste (NE ltaly) with widely different pollution: a natural woodland far from urban and industrial centers, and a site near an ...

  5. An elapsed time-temperature monitor for blood storage.

    Science.gov (United States)

    Harris, G E; Cloud, S; Myhre, B A

    1977-01-01

    Blood should not be allowed to exceed 10 C while being stored or transported. However, one cannot test the internal temperature of a unit of blood without contaminating it. Most blood banks have established an arbitrary time limit beyond which a blood unit cannot be kept out of the refrigerator. This method is ineffective if blood is stored in a satellite refrigerator, since the blood may be moved in and out of the refrigerator and the blood bank personnel will be unaware of it. An elapsed time indicator is described which employs a small condenser (E-Cell-Plessey Electronics) charged with a known amount of electricity. If the device is removed from the refrigerator, it begins to discharge at a known rate. The amount of time subsequently can be determined by the loss of charge. The prototype of this instrument has been found to be quite accurate and small (2 inches X 2 inches X 1 inch). It would be rather inexpensive if made in considerable numbers.

  6. Aging and temperature effects on DOC and elemental release from a metal contaminated soil

    International Nuclear Information System (INIS)

    Martinez, C.E.; Jacobson, A.R.; McBride, M.B.

    2003-01-01

    Increased aging and temperatures may affect DOC element complexes and their release. - The combined effect of time and temperature on elemental release and speciation from a metal contaminated soil (Master Old Site, MOS) was investigated. The soil was equilibrated at 10, 28, 45, 70 and 90 deg. C for 2 days, 2 weeks, and 2 months in the laboratory. Dissolved organic carbon (DOC), total soluble elements (by ICP), and labile metals (by DPASV) were determined in the filtered (0.22 μm) supernatants. For the samples equilibrated at 90 deg. C, DOC fractions were size fractionated by filtration and centrifugation; a subsample was only centrifuged while another was also filtered through a 0.45 μm filter. Analyses of the supernatants (ICP, DPASV, DOC) were performed on all size fraction subsamples. Dissolved organic carbon (DOC) increased both with temperature and incubation time; however, metal behavior was not as uniform. In general, total soluble metal release (ICP) paralleled the behavior of DOC, increasing with both time and temperature, and confirming the importance of soil organic matter (SOM) in metal retention. Voltammetric analysis (dpasv) of Cu and Zn showed that very little of these metals remains labile in solution due, presumably, to complexation with dissolved organic matter. Labile concentrations of Cd, on the other hand, constituted a significant portion (50%) of total soluble Cd. Copper and Al increased in solution with time (up to 2 months) and temperature up to 70 deg. C; however, at 90 deg. C the soluble concentration declined sharply. The same behavior was observed after equilibration for longer periods of time (550 days) at lower temperatures (23 and 70 deg. C). While concentrations of labile Cu and total soluble Cu and Al increased in the unfiltered samples, the trend remained the same. DPASV analysis showing shifts in labile Cu complexes with temperature and time, together with the results from the unfiltered samples, lead to the hypothesis that Cu

  7. Densification and strain hardening of a metallic glass under tension at room temperature.

    Science.gov (United States)

    Wang, Z T; Pan, J; Li, Y; Schuh, C A

    2013-09-27

    The deformation of metallic glasses involves two competing processes: a disordering process involving dilatation, free volume accumulation, and softening, and a relaxation process involving diffusional ordering and densification. For metallic glasses at room temperature and under uniaxial loading, disordering usually dominates, and the glass can fail catastrophically as the softening process runs away in a localized mode. Here we demonstrate conditions where the opposite, unexpected, situation occurs: the densifying process dominates, resulting in stable plastic deformation and work hardening at room temperature. We report densification and hardening during deformation in a Zr-based glass under multiaxial loading, in a notched tensile geometry. The effect is driven by stress-enhanced diffusional relaxation, and is attended by a reduction in exothermic heat and hardening signatures similar to those observed in the classical thermal relaxation of glasses. The result is significant, stable, plastic, extensional flow in metallic glasses, which suggest a possibility of designing tough glasses based on their flow properties.

  8. Theory of metallic magnetism at finite temperatures in bulk materials and thin films

    Science.gov (United States)

    Staunton, J. B.; Razee, S. S. A.; Szunyogh, L.; Gyorffy, B. L.

    2002-06-01

    A review of ‘first-principles’ theoretical work that describes the properties of magnetic metallic materials at finite temperatures is given. The key assumption is that a time-scale separation can be identified. There are the thermally induced spin fluctuations which are long-lived compared to the time electrons take to move from one lattice site to another. The dependence on the spin-polarised electronic structures of the systems is emphasised including the role of ‘local exchange splitting’ inferred even in the paramagnetic states. The disordered local moment picture which provides the basis of a mean field theory is discussed and its results for bulk transition metals and alloys recalled. Finally, new results for this picture in metallic thin films are reported. In particular comparison with calculated magnetic ordering temperatures of iron films on copper substrates is made with those deduced from experiment and an interpretation in terms of the electronic structure is given.

  9. Trends in low-temperature water–gas shift reactivity on transition metals

    DEFF Research Database (Denmark)

    Schumacher, Nana Maria Pii; Boisen, Astrid; Dahl, Søren

    2005-01-01

    Low-temperature water–gas shift reactivity trends on transition metals were investigated with the use of a microkinetic model based on a redox mechanism. It is established that the adsorption energies for carbon monoxide and oxygen can describe to a large extent changes in the remaining activation...

  10. Contribution to the theory of positive muon diffusion in metals at low temperature

    International Nuclear Information System (INIS)

    Yaouanc, A.

    1983-01-01

    We study the temperature dependence of the μ + diffusion in a metal within the small polaron theory. The geometry of the strain field due to an impurity is shown to strongly influence the μ + diffusion properties. We reanalyzed part of the Al data

  11. Thermal crackling: study of the mechanical effects of quick temperature fluctuations on metallic surfaces

    International Nuclear Information System (INIS)

    Pradel, P.

    1984-05-01

    After a brief overview of the thermohydraulical conditions of liquid sodium leading to important temperature fluctuations near the metallic surfaces, the author examines the transfer modes of these fluctuations in the structure thickness and the long term mechanical effects. Dimensioning models based on thermal and metallurgical properties are under study for structures subject to such sodium loads [fr

  12. The effect of welding speed and molten metal peak temperature on ...

    African Journals Online (AJOL)

    The effect of welding speed and molten metal peak temperature on thermal history of an arch - welded steel plate by numerical methods. SM Adedayo. Abstract. No Abstract. Journal of Applied Science, Engineering and Technology Vol. 1(1) 2001: 1-16. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL ...

  13. Prognostic service life assessment of high-strength metallic materials in high temperature environments

    International Nuclear Information System (INIS)

    Danzer, R.

    1988-01-01

    The empirical and theoretical methods for the prediction of service life of high-strength materials are presented. The major mechanisms of failure of metals in high temperatures are given, which include creep and fatigue. The microstructural mechanism of fracture are described, and fracture mechanics methods of analysis and evaluation are explained. (orig./MM) With 92 figs., 6 tabs [de

  14. On the nature of low temperature internal friction peaks in metallic glasses

    NARCIS (Netherlands)

    Khonik, VA; Spivak, LV

    Low temperature (30 metallic glass Ni60Nb40 subjected to preliminary inhomogeneous deformation by cold rolling, homogeneous tensile deformation or electrolytic charging with hydrogen is investigated. Cold rolling or hydrogenation result in appearance of similar

  15. Temperature effect on the static behaviour of adhesively-bonded metal skin to composite stiffener

    NARCIS (Netherlands)

    Teixeira De Freitas, S.; Sinke, J.

    2015-01-01

    The purpose of this research is to study the effect of temperature on the static behavior of an hybrid structure consisting of adhesively bonded Fiber Metal Laminate skin to a composite stiffener. This hybrid structure was tested using stiffener pull-off tests, which is a typical set-up used to

  16. Heavy Metal Pollution Monitoring in Vulnerable Ecosystems: A Case Study of the Lagos Lagoon, Nigeria.

    Science.gov (United States)

    Bawa-Allah, K A; Saliu, J K; Otitoloju, A A

    2018-03-08

    This comparative analysis was carried out to monitor heavy metal concentrations in the Lagos Lagoon over the last 2 decades. Surface water and sediment samples were collected from stations on the Lagos Lagoon based on their suitability for comparative analysis and future monitoring. Heavy metal content in samples was determined using Flame atomic absorption spectrophotometry (FAAS). The concentrations in the samples were compared to those obtained by Don-Pedro et al. (West African Journal of Applied Ecology 5:103-114, 2004) in previous studies from the same sampling zones. Results show that concentration of most heavy metals analysed has reduced significantly (p < 0.05) in the past 2 decades. However, the concentration of Cadmium (Cd) was found to have increased significantly (p < 0.05) over the same period. Increased concentration of Cadmium poses a threat to ecosystem health thus, it is imperative that safe limits for heavy metal discharge in waste streams should be revised and implemented.

  17. Capacity training for the personnel of radiation monitoring in metal recycling; Curso de capacitacion para el personal que realiza la vigilancia radiologica en el reciclaje de metales

    Energy Technology Data Exchange (ETDEWEB)

    Caveda Ramos, C.A.; Dominguez Ley, O., E-mail: caveda@cphr.edu.cu [Centro de Proteccion e Higiene de las Radiaciones, La Habana (Cuba)

    2013-07-01

    In this work it a course for training for the personnel involved in the radiation monitoring of metal recycling is presented. The contents were elaborated taken into account the IAEA recommendations for the development of capacity and training activities in radiological safety and in the Guide for the control of radioactive material in metal recycling. The program is divided in eleven parts and the duration time is two weeks. Among the main covered topics are the requirements for radiation monitoring in metal recycling; response to detection of radioactive material and effects of the ionizing radiation in man and environment.

  18. Temperature effect on hybrid damage monitoring of PSC girder bridges by using acceleration and impedance signatures

    Science.gov (United States)

    Hong, Dong-Soo; Park, Jae-Hyung; Kim, Jeong-Tae; Na, Won-Bae

    2009-03-01

    Acceleration and impedance signatures extracted from a structure are appealing features for a prompt diagnosis on structural condition since those are relatively simple to measure and utilize. However, the feasibility of using them for damage monitoring is limited when their changes go undisclosed due to uncertain temperature conditions, particularly for large structures. In this study, temperature effect on hybrid damage monitoring of prestress concrete (PSC) girder bridges is presented. In order to achieve the objective, the following approaches are implemented. Firstly, a hybrid monitoring algorithm using acceleration and impedance signatures is proposed. The hybrid monitoring algorithm mainly consists of three sequential phases: 1) the global occurrence of damage is alarmed by monitoring changes in acceleration features, 2) the type of damage is identified as either prestress-loss or flexural stiffness-loss by identifying patterns of impedance features, 3) the location and the extent of damage are estimated from damage index method using natural frequency and mode shape changes. Secondly, changes in acceleration and impedance signatures were investigated under various temperature conditions on a laboratory-scaled PSC girder model. Then the relationship between temperatures and those signatures is analyzed to estimate and a set of empirical correlations that will be utilized for the damage alarming and classification of PSC girder bridges. Finally, the feasibility of the proposed algorithm is evaluated by using a lab-scaled PSC girder bridge for which acceleration and impedance signatures were measured for several damage scenarios under uncertain temperature conditions.

  19. Fiber‐optic distributed temperature sensing: A new tool for assessment and monitoring of hydrologic processes

    Science.gov (United States)

    Lane, John W.; Day-Lewis, Frederick D.; Johnson, Carole D.; Dawson, Cian B.; Nelms, David L.; Miller, Cheryl; Wheeler, Jerrod D.; Harvey, Charles F.; Karam, Hanan N.

    2008-01-01

    Fiber‐optic distributed temperature sensing (FO DTS) is an emerging technology for characterizing and monitoring a wide range of important earth processes. FO DTS utilizes laser light to measure temperature along the entire length of standard telecommunications optical fibers. The technology can measure temperature every meter over FO cables up to 30 kilometers (km) long. Commercially available systems can measure fiber temperature as often as 4 times per minute, with thermal precision ranging from 0.1 to 0.01 °C depending on measurement integration time. In 2006, the U.S. Geological Survey initiated a project to demonstrate and evaluate DTS as a technology to support hydrologic studies. This paper demonstrates the potential of the technology to assess and monitor hydrologic processes through case‐study examples of FO DTS monitoring of stream‐aquifer interaction on the Shenandoah River near Locke's Mill, Virginia, and on Fish Creek, near Jackson Hole, Wyoming, and estuary‐aquifer interaction on Waquoit Bay, Falmouth, Massachusetts. The ability to continuously observe temperature over large spatial scales with high spatial and temporal resolution provides a new opportunity to observe and monitor a wide range of hydrologic processes with application to other disciplines including hazards, climate‐change, and ecosystem monitoring.

  20. The Elastic Constants Measurement of Metal Alloy by Using Ultrasonic Nondestructive Method at Different Temperature

    Directory of Open Access Journals (Sweden)

    Eryi Hu

    2016-01-01

    Full Text Available The ultrasonic nondestructive method is introduced into the elastic constants measurement of metal material. The extraction principle of Poisson’s ratio, elastic modulus, and shear modulus is deduced from the ultrasonic propagating equations with two kinds of vibration model of the elastic medium named ultrasonic longitudinal wave and transverse wave, respectively. The ultrasonic propagating velocity is measured by using the digital correlation technique between the ultrasonic original signal and the echo signal from the bottom surface, and then the elastic constants of the metal material are calculated. The feasibility of the correlation algorithm is verified by a simulation procedure. Finally, in order to obtain the stability of the elastic properties of different metal materials in a variable engineering application environment, the elastic constants of two kinds of metal materials in different temperature environment are measured by the proposed ultrasonic method.

  1. Monitoring and Prediction of the Liquid Steel Temperature in the Ladle and Tundish

    Directory of Open Access Journals (Sweden)

    Dorčák, Ľ.

    2006-01-01

    Full Text Available This article is focused on the description of the main features of an online system for the real time monitoring and prediction of the liquid steel temperature in the ladle and tundish. Monitoring and prediction are based on a combination of analytical and statistical methods. Thus e.g., the temperature profiles of the walls are calculated using multi-layer implicit difference scheme taking into account the current temperature of the steel, preheating of the ladle and/or tundish, properties of the refractories, etc. Liquid steel temperatures are calculated from the heat balance of the heat fluxes into the walls and other losses. The influences of all the processes in the secondary metallurgy are taken into account in this system too. The liquid steel temperature prediction is being made continuously during the processing of steel from the LD converter to the continuous casting.

  2. Comparison of Microtox and Xenoassay Light as a Near Real Time River Monitoring Assay for Heavy Metals

    Directory of Open Access Journals (Sweden)

    M. I. E. Halmi

    2014-01-01

    Full Text Available Luminescence-based assays for toxicants such as Microtox, ToxAlert, and Biotox have been used extensively worldwide. However, the use of these assays in near real time conditions is limited due to nonoptimal assay temperature for the tropical climate. An isolate that exhibits a high luminescence activity in a broad range of temperatures was successfully isolated from the mackerel, Rastrelliger kanagurta. This isolate was tentatively identified as Photobacterium sp. strain MIE, based on partial 16S rDNA molecular phylogeny. Optimum conditions that support high bioluminescence activity occurred between 24 and 30°C, with pH 5.5 to 7.5, 10 to 20 g/L of sodium chloride, 30 to 50 g/L of tryptone, and 4 g/L of glycerol as the carbon source. Assessment of near real time capability of this bacterial system, Xenoassay light to monitor heavy metals from a contaminated river running through the Juru River Basin shows near real time capability with assaying time of less than 30 minutes per samples. Samples returned to the lab were tested with a standard Microtox assay using Vibrio fishceri. Similar results were obtained to Xenoassay light that show temporal variation of copper concentration. Thus, this strain is suitable for near real time river monitoring of toxicants especially in the tropics.

  3. Design and Evaluation of a Pressure and Temperature Monitoring System for Pressure Ulcer Prevention

    Directory of Open Access Journals (Sweden)

    Farve Daneshvar Fard

    2014-08-01

    Full Text Available Introduction Pressure ulcers are tissue damages resulting from blood flow restriction, which occurs when the tissue is exposed to high pressure for a long period of time. These painful sores are common in patients and elderly, who spend extended periods of time in bed or wheelchair. In this study, a continuous pressure and temperature monitoring system was developed for pressure ulcer prevention. Materials and Methods The monitoring system consists of 64 pressure and 64 temperature sensors on a 40×50 cm2 sheet. Pressure and temperature data and the corresponding maps were displayed on a computer in real-time. Risk assessment could be performed by monitoring and recording absolute pressure and temperature values, as well as deviations over time. Furthermore, a posture detection procedure was proposed for sitting posture identification. Information about the patient’s movement history may help caregivers make informed decisions about the patient’s repositioning and ulcer prevention strategies. Results Steady temporal behaviour of the designed system and repeatability of the measurements were evaluated using several particular tests. The results illustrated that the system could be utilized for continuous monitoring of interface pressure and temperature for pressure ulcer prevention. Furthermore, the proposed method for detecting sitting posture was verified using a statistical analysis. Conclusion A continuous time pressure and temperature monitoring system was presented in this study. This system may be suited for pressure ulcer prevention given its feasibility for simultaneous monitoring of pressure and temperature and alarming options. Furthermore, a method for detecting different sitting postures was proposed and verified. Pressure ulcers in wheelchair-bound patients may be prevented using this sitting posture detection method.

  4. The Interchangeability of Plasma and Whole Blood Metal Ion Measurement in the Monitoring of Metal on Metal Hips

    Directory of Open Access Journals (Sweden)

    Ibrahim A. Malek

    2015-01-01

    Full Text Available One hundred and twenty six paired samples of plasma and whole blood were measured with inductively coupled plasma mass spectrometry technique for metal ions analysis to determine a relationship between them. There was a significant difference between the mean plasma and whole blood concentrations of both cobalt (Co and chromium (Cr (p<0.0001 for both Co and Cr. The mean ratio between plasma and whole blood Cr and Co was 1.56 (range: 0.39–3.85 and 1.54 (range: 0.64–18.26, respectively, but Bland and Altman analysis illustrated that this relationship was not universal throughout the range of concentrations. There was higher variability at high concentrations for both ions. We conclude that both these concentrations should not be used interchangeably and conversion factors are unreliable due to concentration dependent variability.

  5. Low Power Operation of Temperature-Modulated Metal Oxide Semiconductor Gas Sensors.

    Science.gov (United States)

    Burgués, Javier; Marco, Santiago

    2018-01-25

    Mobile applications based on gas sensing present new opportunities for low-cost air quality monitoring, safety, and healthcare. Metal oxide semiconductor (MOX) gas sensors represent the most prominent technology for integration into portable devices, such as smartphones and wearables. Traditionally, MOX sensors have been continuously powered to increase the stability of the sensing layer. However, continuous power is not feasible in many battery-operated applications due to power consumption limitations or the intended intermittent device operation. This work benchmarks two low-power, duty-cycling, and on-demand modes against the continuous power one. The duty-cycling mode periodically turns the sensors on and off and represents a trade-off between power consumption and stability. On-demand operation achieves the lowest power consumption by powering the sensors only while taking a measurement. Twelve thermally modulated SB-500-12 (FIS Inc. Jacksonville, FL, USA) sensors were exposed to low concentrations of carbon monoxide (0-9 ppm) with environmental conditions, such as ambient humidity (15-75% relative humidity) and temperature (21-27 °C), varying within the indicated ranges. Partial Least Squares (PLS) models were built using calibration data, and the prediction error in external validation samples was evaluated during the two weeks following calibration. We found that on-demand operation produced a deformation of the sensor conductance patterns, which led to an increase in the prediction error by almost a factor of 5 as compared to continuous operation (2.2 versus 0.45 ppm). Applying a 10% duty-cycling operation of 10-min periods reduced this prediction error to a factor of 2 (0.9 versus 0.45 ppm). The proposed duty-cycling powering scheme saved up to 90% energy as compared to the continuous operating mode. This low-power mode may be advantageous for applications that do not require continuous and periodic measurements, and which can tolerate slightly higher

  6. Impedance monitoring at tendon-anchorage via mountable PZT interface and temperature-effect compensation

    Science.gov (United States)

    Huynh, Thanh-Canh; Nguyen, Tuan-Cuong; Choi, Sang-Hoon; Kim, Jeong-Tae

    2016-04-01

    In this study, the pre-stress force in pre-stressed concrete (PSC) girders is monitored via mountable PZT interface under varying temperature. Firstly, an impedance-based technique using mountable PZT interface is proposed for pre-stress-loss monitoring in tendon-anchorage systems. A cross correlation-based temperature-effect compensation algorithm using an effective frequency shift (EFS) of impedance signatures is visited. Secondly, lab-scale experiments are performed on a PSC girder instrumented with a mountable PZT interface at tendon-anchorage. A series of temperature variation and pre-stress-loss events are simulated for the lab-scale PSC girder. Thirdly, the feasibility of the mountable PZT interface for pre-stress-loss monitoring in tendon-anchorage is experimentally verified under constant temperature conditions. Finally, the PZT interface device is examined for pre-stress-loss monitoring under temperature changes to validate its applicability. The temperature effect on impedance signatures is compensated by minimizing cross-correlation deviation between impedance patterns of the mountable PZT interface.

  7. Quantification of temperature effect on impedance monitoring via PZT interface for prestressed tendon anchorage

    Science.gov (United States)

    Huynh, Thanh-Canh; Kim, Jeong-Tae

    2017-12-01

    In this study, the quantification of temperature effect on impedance monitoring via a PZT interface for prestressed tendon-anchorage is presented. Firstly, a PZT interface-based impedance monitoring technique is selected to monitor impedance signatures by predetermining sensitive frequency bands. An analytical model is designed to represent coupled dynamic responses of the PZT interface-tendon anchorage system. Secondly, experiments on a lab-scaled tendon anchorage are described. Impedance signatures are measured via the PZT interface for a series of temperature and prestress-force changes. Thirdly, temperature effects on measured impedance responses of the tendon anchorage are estimated by quantifying relative changes in impedance features (such as RMSD and CCD indices) induced by temperature variation and prestress-force change. Finally, finite element analyses are conducted to investigate the mechanism of temperature variation and prestress-loss effects on the impedance responses of prestressed tendon anchorage. Temperature effects on impedance monitoring are filtered by effective frequency shift-based algorithm for distinguishing prestress-loss effects on impedance signatures.

  8. Temperature dependence of the Hall angle in a correlated three-dimensional metal

    Science.gov (United States)

    Rosenbaum, T. F.; Husmann, A.; Carter, S. A.; Honig, J. M.

    1998-06-01

    The Hall coefficient, RH, of the Mott-Hubbard system vanadium sesquioxide has a strong temperature dependence in the barely delocalized metal. As in the case of the cuprate superconductors, we find that the resistivity and the Hall angle of V2-yO3 follow different power laws in temperature, implying different longitudinal and transverse scattering mechanisms. Far from half-filling, only one transport scattering rate is needed to describe the data, at which point the temperature dependence of RH disappears.

  9. The electromagnetic force field, fluid flow field and temperature profiles in levitated metal droplets

    Science.gov (United States)

    El-Kaddah, N.; Szekely, J.

    1982-01-01

    A mathematical representation was developed for the electromagnetic force field, the flow field, the temperature field (and for transport controlled kinetics), in a levitation melted metal droplet. The technique of mutual inductances was employed for the calculation of the electromagnetic force field, while the turbulent Navier - Stokes equations and the turbulent convective transport equations were used to represent the fluid flow field, the temperature field and the concentration field. The governing differential equations, written in spherical coordinates, were solved numerically. The computed results were in good agreement with measurements, regarding the lifting force, and the average temperature of the specimen and carburization rates, which were transport controlled.

  10. Online Chip Temperature Monitoring Using υce-Load Current and IR Thermography

    DEFF Research Database (Denmark)

    Ghimire, Pramod; Pedersen, Kristian Bonderup; Trintis, Ionut

    2015-01-01

    This paper presents on-state collector-emitter voltage (υce, on)-load current (Ic) method to monitor chip temperature on power insulated gate bipolar transistor (IGBT) modules in converter operation. The measurement method is also evaluated using infrared (IR) thermography. Temperature dependencies...... of υce, on at load current is measured and temperature dependency calibration factor is formulated. This method needs a correction to compensate a deviation in the interconnection resistance from homogeneous temperature field in calibration to non-homogeneous field in loading. The correction parameter...

  11. Monitoring sea level and sea surface temperature trends from ERS satellites

    DEFF Research Database (Denmark)

    Andersen, Ole Baltazar; Knudsen, Per; Beckley, B.

    2002-01-01

    Data from the two ESA satellites ERS-1 and ERS-2 are used in global and regional analysis of sea level and sea surface temperature trends over the last, 7.8 years. T he ERS satellites and in the future the ENVISAT satellite provide unique opportunity for monitoring both changes in sea level and sea...... surface temperature as these satellites are equipped with an altimeter to measure sea level height as well as an along track scanning radiometer (ATSR) to measure the sea surface temperature. Consistent increase in both sea level and sea surface temperatures are found in most parts of the Atlantic Ocean...

  12. Heavy metals monitoring in mussels Mytilus galloprovincialis from the Apulian coasts (Southern Italy

    Directory of Open Access Journals (Sweden)

    L. SPADA

    2013-02-01

    Full Text Available Concentrations of six heavy metals (Cd, Cr, Cu, Hg, Pb and Zn and one semi-metal (As were determined in tissues of mussels Mytilus galloprovincialis collected along the Apulian coasts (Mediterranean sea. This project, performed in 2009, was targeted toward the assessment of levels and spatial distribution of metals in the environment in order to evaluate the coastal water quality using mussels as bioindicators and health risk for mussel consumers.The concentrations (mg/kg d.w. of these metals ranged from 6.35 to 76.17 for arsenic (As, 0.38 to 2.54 for cadmium (Cd, 0.96 to 9.46 for chromium (Cr, 5.26 to 19.22 for copper (Cu, 0.10 to 0.81 for mercury (Hg, 25.00 to 110.51 for zinc (Zn and from 0.37 to 3.25 for lead (Pb. These levels were lower than the permissible limits set by European Commission and FAO with the exception for Cr in three sampling stations. Evaluation of the risk associated to molluscs consumption for human health suggested that there is no evident risk for a moderate Mytilus g. consumer, however heavy metals concentrations must be monitored periodically and carefully with respect to the consumers health.

  13. Corrosion Monitoring of Flexible Metallic Substrates for Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Trystan Watson

    2013-01-01

    Full Text Available Two techniques for monitoring corrosion within a dye-sensitized solar cell (DSC system are presented, which enable continuous, high sensitivity, in situ measurement of electrolyte breakdown associated with DSCs fabricated on metals. The first method uses UV/Vis reflectance spectrophotometry in conjunction with encapsulation cells, which incorporate a 25 μm thick electrolyte layer, to provide highly resolved triiodide absorption data. The second method uses digital image capture to extract colour intensity data. Whilst the two methods provide very similar kinetic data on corrosion, the photographic method has the advantage that it can be used to image multiple samples in large arrays for rapid screening and is also relatively low cost. This work shows that the triiodide electrolyte attacks most metals that might be used for structural applications. Even a corrosion resistant metal, such as aluminium, can be induced to corrode through surface abrasion. This result should be set in the context with the finding reported here that certain nitrogen containing heterocyclics used in the electrolyte to enhance performance also act as corrosion inhibitors with significant stabilization for metals such as iron. These new techniques will be important tools to help develop corrosion resistant metal surfaces and corrosion inhibiting electrolytes for use in industrial scale devices.

  14. Mechanism of high-temperature background of internal friction in metals

    International Nuclear Information System (INIS)

    Shapoval, B.I.; Arzhavitin, V.M.

    1988-01-01

    Data of theoretical and experimental studies on energy dissipation in vibrating metal at small amplitudes and elevated temperatures (high temperature background of internal friction) are generalized and systematized. Evolution of knowledge of the background as a phenomenon influenced mainly by crystal structure defects - their form, quantity, mobility and interaction is followed. Considered is a wide range of investigated metal states and measurement conditions, and interrelations with other characteristics, for instance, strength ones. On the basis of the data obtained by authors and other investigations a concept of an additional third stage of the background increase with the temperature - the stage of deviation from exponential dependence at premelting point, is introduced. 107 refs.; 32 figs.; 3 tabs

  15. On the nature of low temperature internal friction peaks in metallic glasses

    Energy Technology Data Exchange (ETDEWEB)

    Khonik, V.A. [State Pedagogical Univ., Voronezh (Russian Federation); Spivak, L.V. [State Univ., Perm (Russian Federation)

    1996-01-01

    Low temperature (30 < T < 300 K) internal friction in a metallic glass Ni{sub 60}Nb{sub 40} subjected to preliminary inhomogeneous deformation by cold rolling, homogeneous tensile deformation or electrolytic charging with hydrogen is investigated. Cold rolling or hydrogenation result in appearance of similar internal friction peaks and hysteresis damping. Homogeneous deformation has no influence on low temperature internal friction. The phenomenon of microplastic deformation during hydrogenation of weakly stressed samples is revealed. It is argued that microplastic deformation of metallic glasses during hydrogenation without external stress takes place too. Plastic flow both on cold rolling and hydrogenation occurs via formation and motion of dislocation-like defects which are the reason of the observed anelastic anomalies. It is concluded that low temperature internal friction peaks described in the literature for as-cast, cold deformed and hydrogenated samples have common dislocation-like origin.

  16. Real-time Monitoring on the Tunnel Wall Movement and Temperature Variation of KURT Facility

    International Nuclear Information System (INIS)

    Kim, Kyung Su; Bae, Dae Seok; Koh, Young Kwon; Choi, Jong Won

    2010-04-01

    The optical fiber cable acting as a sensor was embedded in the underground research tunnel and portal area in order to monitor their stability and the spatial temperature variation. This system includes two types of sensing function to monitor the distributed strain and temperature along the line, where sensor cable is installed, not a point sensing. The measurement resolution for rock mass displacement is 1 mm per 1 m and it covers 30 km length with every 1 m interval in minimum. In temperature, the cable measures the range of -160∼600 .deg. C with 0.01 .deg. C resolution according to the cable types. This means that it would be applicable to monitoring system for the safe operation of various kinds of facilities having static and/or dynamic characteristics, such as chemical plant, pipeline, rail, huge building, long and slim structures, bridge, subway and marine vessel. etc

  17. High Temperatures Health Monitoring of the Condensed Water Height in Steam Pipe Systems

    Science.gov (United States)

    Lih, Shyh-Shiuh; Bar-Cohen, Yoseph; Lee, Hyeong Jae; Badescu, Mircea; Bao, Xiaoqi; Sherrit, Stewart; Takano, Nobuyuki; Ostlund, Patrick; Blosiu, Julian

    2013-01-01

    Ultrasonic probes were designed, fabricated and tested for high temperature health monitoring system. The goal of this work was to develop the health monitoring system that can determine the height level of the condensed water through the pipe wall at high temperature up to 250 deg while accounting for the effects of surface perturbation. Among different ultrasonic probe designs, 2.25 MHz probes with air backed configuration provide satisfactory results in terms of sensitivity, receiving reflections from the target through the pipe wall. A series of tests were performed using the air-backed probes under irregular conditions, such as surface perturbation and surface disturbance at elevated temperature, to qualify the developed ultrasonic system. The results demonstrate that the fabricated air-backed probes combined with advanced signal processing techniques offer the capability of health monitoring of steam pipe under various operating conditions.

  18. Brown algae ( Phaeophyta) for monitoring heavy metals at the Sudanese Red Sea coast

    Science.gov (United States)

    Ali, Abuagla Y. A.; Idris, Abubakr M.; Ebrahim, Ammar M.; Eltayeb, Mohmaed A. H.

    2017-11-01

    This study aimed at monitoring some heavy metals at the Sudanese Red Sea coast using Brown algae ( Phaeophyta) as biomonitor. The total contents of heavy metals in four species ( Turbinaria sp., Sargassum sp., Cystoseira sp. and Padina sp.) as well as seawater were examined. Twenty-six algae samples were collected from seven locations. The ranges of concentrations (µg/g, dry wt.) of heavy metals in algae were 4.95-16.95 for Cr, 2.93-257.32 for Mn, 1.35-7.43 for Ni, 0.83-14.10 for Cu, 4.13-19.13 for Zn, 0.03-0.15 for Cd and 0.45-2.18 for Pb. The ranges of the pH and the salinity of seawater from the same locations were 8.11-8.82 and 38.00-41.00 PSU, respectively. The ranges of concentrations (µg/L) of heavy metals in seawater were 7.00-11.00 for Cr, 2.90-10.20 for Mn, 6.70-10.10 for Ni, 1.70-5.00 for Cu, 0.94-5.70 for Zn, 0.09-0.14 for Cd and 0.93-1.80 for Pb. No significant correlations between metal concentrations in algae and seawater were observed. Some locations in the study area recorded relatively high levels of heavy metals in algae indicating possible contribution from manmade activities. Cr recorded higher levels in the study area than those in other coastal areas in the word. Padina sp. and Cystoseira sp. were better bioindicator than Turbinaria sp., Sargassum sp. for their high metal uptake.

  19. Diurnal and seasonal trends and source apportionment of redox-active metals in Los Angeles using a novel online metal monitor and Positive Matrix Factorization (PMF)

    Science.gov (United States)

    Mousavi, Amirhosein; Sowlat, Mohammad H.; Sioutas, Constantinos

    2018-02-01

    In the present study, we identified the sources of four redox-active metals, including Iron (Fe), Chromium (Cr), Cupper (Cu), and Manganese (Mn) and quantified the contribution of these sources to PM2.5 concentrations in central Los Angeles, California, by employing time-resolved measurements (i.e., a time resolution of 2 h) with a recently developed online metal monitor and Positive Matrix Factorization (PMF). Size distribution of ambient PM (14 nm-10 μm) was measured using the Scanning Mobility Particle Sizer (SMPS) and Optical Particle Sizer (OPS). Auxiliary variables were also collected, including elemental (EC) and organic carbon (OC), gaseous pollutants (NO2 and O3), meteorological parameters (including relative humidity (RH) and temperature), and traffic data (for heavy- (HDVs) and light-duty vehicles (LDVs)). A 4-factor solution was found to be optimum for the chemically-speciated dataset, whereas a 5-factor solution appeared to be most plausible for the size distribution data. The factors included fresh traffic, soil/road dust, urban background aerosol, secondary aerosol, and nucleation (only resolved for the size distribution data). Fresh traffic was the major contributor to Fe and Cu concentrations, whereas Cr was mostly found in the urban background aerosol (reflecting a mixture of small local sources as well as aged traffic emissions), and Mn mostly came from both soil/road dust and was to a lesser degree found in urban background aerosol. Secondary aerosol did not contribute to the concentrations of any of these metals, but was associated with very high loading of OC, as expected. Even though the urban background aerosol and secondary aerosol appeared to be characterized by "aged" particles and have a rather homogeneous spatial distribution, the reactions and processes involved in their formation are entirely different. Our results provide insights into the sources of redox-active metals in central Los Angeles. They also underscore the benefits of

  20. Investigation of the Temperature Sensors Accuracy in the Temperature Monitoring System for the Welded Joints of the Industrial Power Supply Main Busways

    Science.gov (United States)

    Grivennaya, N. V.; Bazhenov, A. V.; Bondareva, G. A.; Malygin, S. V.; Knyaginin, A. A.

    2018-01-01

    The article is devoted to the substantiation of the technical solution of the remote monitoring system for the temperature changes of main and branch busways of power supply to industrial enterprises of increased environmental danger. When monitoring the temperature of trunk buses of AC mains up to 1000 V, heated by an electric current, errors occur due to various factors. Studies have been carried out to evaluate the effect of temperature of surrounding objects (including neighboring busbars) on the accuracy of temperature measurements. Conclusions are made about the possibility of using alternative versions of temperature sensors as the basis of the monitoring system.

  1. Non-invasive temperature monitoring using small coils during radio-frequency heating

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, Takeo; Gu, Yeun Hwa; Ushiba, Hiroaki; Hara, Kensaku; Hashimoto, Tatsuya; Nohara, Yuushi [Suzuka University, Mie (Japan); Hasegawa, Takashi [Accelerator Engineering Co, Chiba (Japan); Yamamoto, Itsuo [Yamamoto Vinyter Co, Osaka (Japan)

    1999-07-01

    In hyperthermia treatment of malignant tumors, thermal tissue injury increases drastically with every degree of increase in the tissue temperature above 42.5 .deg. C Accurate temperature monitoring during hyperthermia is important. Therefore, we developed a non-invasive method to monitor the tissue temperature during radio-frequency hyperthermia by detecting the magnetic field induced by the radio-frequency currents that flow through the heated tissue. This technique uses small multi-channel coil antennas to detect radio-frequency currents and generates two-dimensional distribution in the tissue. A rectifying circuit was connected to each coil antenna, and the current was converted with a fixed resistance into voltage. Since the voltage output from each antenna was attenuated at 1/2pr (r: distance from the radio-frequency current), single-peaked projection data were prepared, and after treatment of various signals, radio-frequency currents that flowed through the heated object were determined as a two-dimensional current distribution profile by back-projection. A high correlation was observed between the distribution of radio-frequency currents detected with the coil antennas and the temperature distribution detected by thermography. Our method of the temperature distribution suggests the possibility of non-invasive evaluation of the temperature distribution in the target of hyperthermia and clinical usefulness of this method for temperature monitoring during hyperthermia.

  2. Holter monitoring of central and peripheral temperature: possible uses and feasibility study in outpatient settings.

    Science.gov (United States)

    Varela, Manuel; Cuesta, David; Madrid, Juan Antonio; Churruca, Juan; Miro, Pau; Ruiz, Raul; Martinez, Carlos

    2009-08-01

    Conventional clinical thermometry has important limitations. A continuous monitoring of temperature may offer significant advantages, including the use of chronobiological and complexity analysis of temperature profile and eventually the identification of a "pre-febrile" pattern. We present a clinical model designed to measure, store and/or transmit in real time a central and a peripheral temperature reading. The results of its use in a healthy, free-living population is reported. Thirty subjects (15 women, 15 men, 20-70 years old), were monitored for 24 h while following their normal life. Temperatures were recorded every minute at the external auditory channel (EAC) and on the skin, at the intersection of the 5th intercostal space and the anterior axillary line. A Cosinor analysis and Approximate Entropy (ApEn) (m = 2, r = 0.15*SD, N = 180) were calculated for both temperatures. Median temperature was 35.55 degrees C [interquartile range (IR) 0.77 degrees C] in the external auditory channel (EAC) and 34.62 degrees C (IR 1.61) in the specified skin location. Median gradient between AEC and skin was 0.93 (IR 1.57). A circadian rhythm was present both in EAC and skin temperature, with a mean amplitude of 0.44 degrees C and an acrophase at 21:02 for the EAC and 0.70 degrees C and 00:42 for the skin. During the night there was a sizable increase in peripheral temperature, with a decrease in gradient and a loss of complexity in the temperature profile, most significantly in the peripheral temperature. Continuous monitoring of central and peripheral temperature may be a helpful tool in both ambulatory and admitted patients and may offer new approaches in clinical thermometry.

  3. Metal release behavior of surface oxidized stainless steels into flowing high temperature pure water

    International Nuclear Information System (INIS)

    Fujiwara, Kazuo; Tomari, Haruo; Nakayama, Takenori; Shimogori, Kazutoshi; Ishigure, Kenkichi; Matsuura, Chihiro; Fujita, Norihiko; Ono, Shoichi.

    1987-01-01

    In order to clarify the effect of oxidation treatment of Type 304 SS on the inhibition of metal release into high temperature pure water, metal release rate of individual alloying element into flowing deionized water containing 50 ppb dissolved oxygen was measured as the function of exposure time on representative specimens oxidized in air and steam. The behavior of metal release was also discussed in relation to the structure of surface films. Among the alloying elements the amount of Fe ion, Cr ion and Fe crud in high temperature pure water tended to saturate with the exposure time and that of Ni ion and Co ion tended to increase monotonously with the exposure time for all specimens tested. And the treatment of steam-oxidation was the most effective to decrease the metal release of alloying elements and the treatment by air-oxidation also decreased the metal release. These tendencies were confirmed to correlate well with the structure of the surface films as it was in the results in the static autoclave test. (author)

  4. Metal-Silicate Equilibration at Super-Liquidus Temperatures During Core Formation

    Science.gov (United States)

    Hernlund, J. W.; Ichikawa, H.; Labrosse, S.; Kameyama, M.

    2014-12-01

    Experimental constraints on the partitioning of moderately siderophile elements between metal and silicates during core formation suggest equilibration temperatures significantly greater than the liquidus of the silicate Earth (e.g., Wade and Wood, 2005). However, because equilibration was considered to occur in a ponded metal at the silicate solidus, such high temperature equilibration was rejected as implausible. Instead, lower temperature equilibration with variable oxygen fugacity was proposed as an alternative, although the plausibility of the physical mechanisms invoked in this scenario is also questionable. We have re-visited the model of metal-silicate separation in large molten pockets following energetic accretion events, and find that silicate-metal equlibration is most rapid when the iron rains out of the magma, and the release of gravitational potential energy by this rain heats the mixture by as much as 1000 K above the liquidus. However, the first drops of iron rain to pond at the base of the molten pocket will equilibrate at lower temperatures, and only the final drops will be subject to the highest temperatures. We model rain fall and heating of the magma by viscous dissipation to calculate the effective pressure-temperature conditions for partitioning in this scenario, and find that effective pressure conditions are smaller than the pressure at the base of the molten pocket. The ponded metal itself is gravitationally stratified (both in composition and temperature), and is not expected to convect or mix until it undergoes subsequent downward transport into the Earth's core. We also suggest that such a process operating during the very largest giant impact events (extending into the deep mantle) may have given rise to a buoyant oxygen-enriched metal layer atop the outer core, as suggested by some seismological models of the present-day Earth (e.g., Helffrich and Kaneshima, 2010). References: Helffrich, G. and S. Kaneshima (2010), Outer

  5. Monitoring of heavy metal particle emission in the exhaust duct of a foundry using LIBS.

    Science.gov (United States)

    Dutouquet, C; Gallou, G; Le Bihan, O; Sirven, J B; Dermigny, A; Torralba, B; Frejafon, E

    2014-09-01

    Heavy metals have long been known to be detrimental to human health and the environment. Their emission is mainly considered to occur via the atmospheric route. Most of airborne heavy metals are of anthropogenic origin and produced through combustion processes at industrial sites such as incinerators and foundries. Current regulations impose threshold limits on heavy metal emissions. The reference method currently implemented for quantitative measurements at exhaust stacks consists of on-site sampling of heavy metals on filters for the particulate phase (the most prominent and only fraction considered in this study) prior to subsequent laboratory analysis. Results are therefore known only a few days after sampling. Stiffer regulations require the development of adapted tools allowing automatic, on-site or even in-situ measurements with temporal resolutions. The Laser-Induced Breakdown Spectroscopy (LIBS) technique was deemed as a potential candidate to meet these requirements. On site experiments were run by melting copper bars and monitoring emission of this element in an exhaust duct at a pilot-scale furnace in a French research center dedicated to metal casting. Two approaches designated as indirect and direct analysis were broached in these experiments. The former corresponds to filter enrichment prior to subsequent LIBS interrogation whereas the latter entails laser focusing right through the aerosol for detection. On-site calibration curves were built and compared with those obtained at laboratory scale in order to investigate possible matrix and analyte effects. Eventually, the obtained results in terms of detection limits and quantitative temporal monitoring of copper emission clearly emphasize the potentialities of the direct LIBS measurements. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Microstructure and mechanical properties of metallic high-temperature materials. Research report

    International Nuclear Information System (INIS)

    Mughrabi, H.; Gottstein, G.; Mecking, H.; Riedel, H.; Toboloski, J.

    1999-01-01

    This volume contains 38 lectures of research studies performed in the course of the Priority Programme 'Microstructure and Mechanical Properties of Metallic High-Temperature Materials' supported by the Deutsche Forschungsgemeinschaft (DFG) over a period of six years from 1991 to 1997. The four materials selected were: 1. light metal PM-aluminium and titanium base alloys; 2. ferritic chromium and austenitic alloy 800 steels; 3. (monocrystalline) nickel-base superalloys; and 4. nickel- and iron-base oxide-dispersion-strengthened superalloys. All papers have been abstracted separately for the ENERGY database

  7. Using Wireless Sensor Networks to Achieve Intelligent Monitoring for High-Temperature Gas-Cooled Reactor

    Directory of Open Access Journals (Sweden)

    Jianghai Li

    2017-01-01

    Full Text Available High-temperature gas-cooled reactors (HTGR can incorporate wireless sensor network (WSN technology to improve safety and economic competitiveness. WSN has great potential in monitoring the equipment and processes within nuclear power plants (NPPs. This technology not only reduces the cost of regular monitoring but also enables intelligent monitoring. In intelligent monitoring, large sets of heterogeneous data collected by the WSN can be used to optimize the operation and maintenance of the HTGR. In this paper, WSN-based intelligent monitoring schemes that are specific for applications of HTGR are proposed. Three major concerns regarding wireless technology in HTGR are addressed: wireless devices interference, cybersecurity of wireless networks, and wireless standards selected for wireless platform. To process nonlinear and non-Gaussian data obtained by WSN for fault diagnosis, novel algorithms combining Kernel Entropy Component Analysis (KECA and support vector machine (SVM are developed.

  8. Spatio-temporal behavior of brightness temperature in Tel-Aviv and its application to air temperature monitoring

    International Nuclear Information System (INIS)

    Pelta, Ran; Chudnovsky, A. Alexandra; Schwartz, Joel

    2016-01-01

    This study applies remote sensing technology to assess and examine the spatial and temporal Brightness Temperature (BT) profile in the city of Tel-Aviv, Israel over the last 30 years using Landsat imagery. The location of warmest and coldest zones are constant over the studied period. Distinct diurnal and temporal BT behavior divide the city into four different segments. As an example of future application, we applied mixed regression models with daily random slopes to correlate Landsat BT data with monitored air temperature (Tair) measurements using 14 images for 1989–2014. Our preliminary results show a good model performance with R 2  = 0.81. Furthermore, based on the model's results, we analyzed the spatial profile of Tair within the study domain for representative days. - Highlights: • The location of warmest and coldest zones are constant over the last 30 years. • Distinct diurnal and temporal Brightness Temperature behavior divide the city into four segments. • We assess air temperature from satellite surface temperature (R 2  = 0.81). - The location of warmest and coldest zones are constant over the last 30 years. Distinct diurnal and temporal Surface Temperature behavior divide the city into four different segments.

  9. Variant selection of martensites in steel welded joints with low transformation temperature weld metals

    International Nuclear Information System (INIS)

    Takahashi, Masaru; Yasuda, Hiroyuki Y.

    2013-01-01

    Highlights: ► We examined the variant selection of martensites in the weld metals. ► We also measured the residual stress developed in the butt and box welded joints. ► 24 martensite variants were randomly selected in the butt welded joint. ► High tensile residual stress in the box welded joint led to the strong variant selection. ► We discussed the rule of the variant selection focusing on the residual stress. -- Abstract: Martensitic transformation behavior in steel welded joints with low transformation temperature weld (LTTW) metal was examined focusing on the variant selection of martensites. The butt and box welded joints were prepared with LTTW metals and 980 MPa grade high strength steels. The residual stress of the welded joints, which was measured by a neutron diffraction technique, was effectively reduced by the expansion of the LTTW metals by the martensitic transformation during cooling after the welding process. In the LTTW metals, the retained austenite and martensite phases have the Kurdjumov–Sachs (K–S) orientation relationship. The variant selection of the martensites in the LTTW metals depended strongly on the type of welded joints. In the butt welded joint, 24 K–S variants were almost randomly selected while a few variants were preferentially chosen in the box welded joint. This suggests that the high residual stress developed in the box welded joint accelerated the formation of specific variants during the cooling process, in contrast to the butt welded joint with low residual stress

  10. Fatigue and creep crack growth behaviour at high temperatures for weld metals of Alloy 800 and Alloy 617

    International Nuclear Information System (INIS)

    Roedig, M.; Choudhary, B.K.

    1993-01-01

    High temperature fatigue crack growth (FCG) and creep crack growth (CCG) experiments have been conducted in air on weld metal, heat affected zone (HAZ) and base metal of the austenitic Alloy 800 and the nickel base Alloy 617. Tests were performed on specimens machined from pipes, in the temperature range 550-900 deg. C. The crack propagation mode was examined. At all temperatures and for both materials, FCG of base metal was found to be the highest, whereas the weld metal exhibited the lowest FCG rate. The FCG rate in the HAZ was found to lie in between of those observed for base and weld metal. The crack propagation mode remained transgranular in base metal and transdendritic in weld metal at all temperatures. CCG behaviour could be described using the energy rate integral C*. Base metal and weld metal exhibited similar CCG rate at same C*. The crack propagation mode under CCG condition was found to be intergranular in base metal and HAZ and interdendritic in the weld metal. (author)

  11. Metal viscoplasticity with two-temperature thermodynamics and two dislocation densities

    Science.gov (United States)

    Roy Chowdhury, Shubhankar; Kar, Gurudas; Roy, Debasish; Reddy, J. N.

    2018-03-01

    Posed within the two-temperature theory of non-equilibrium thermodynamics, we propose a model for thermoviscoplastic deformation in metals. We incorporate the dynamics of dislocation densities-mobile and forest—that play the role of internal state variables in the formulation. The description based on two temperatures appears naturally when one recognizes that the thermodynamic system undergoing viscoplastic deformation is composed of two weakly interacting subsystems, viz. a kinetic-vibrational subsystem of the vibrating atomic lattices and a configurational subsystem of the slower degrees of freedom relating to defect motion, each with its own temperature. Starting with a basic model that involves only homogeneous deformation, a three-dimensional model for inhomogeneous viscoplasticity applicable to finite deformation is charted out in an overstress driven viscoplastic deformation framework. The model shows how the coupled evolutions of mobile and forest dislocation densities, which are critically influenced by the dynamics of configurational temperature, govern the strength and ductility of the metal. Unlike most contemporary models, the current proposal also affords a prediction of certain finer details as observed in the experimental data on stress-strain behaviour of metals and this in turn enhances the understanding of the evolving and interacting dislocation densities.

  12. Metal viscoplasticity with two-temperature thermodynamics and two dislocation densities

    Science.gov (United States)

    Roy Chowdhury, Shubhankar; Kar, Gurudas; Roy, Debasish; Reddy, J. N.

    2017-12-01

    Posed within the two-temperature theory of non-equilibrium thermodynamics, we propose a model for thermoviscoplastic deformation in metals. We incorporate the dynamics of dislocation densities-mobile and forest—that play the role of internal state variables in the formulation. The description based on two temperatures appears naturally when one recognizes that the thermodynamic system undergoing viscoplastic deformation is composed of two weakly interacting subsystems, viz. a kinetic-vibrational subsystem of the vibrating atomic lattices and a configurational subsystem of the slower degrees of freedom relating to defect motion, each with its own temperature. Starting with a basic model that involves only homogeneous deformation, a three-dimensional model for inhomogeneous viscoplasticity applicable to finite deformation is charted out in an overstress driven viscoplastic deformation framework. The model shows how the coupled evolutions of mobile and forest dislocation densities, which are critically influenced by the dynamics of configurational temperature, govern the strength and ductility of the metal. Unlike most contemporary models, the current proposal also affords a prediction of certain finer details as observed in the experimental data on stress-strain behaviour of metals and this in turn enhances the understanding of the evolving and interacting dislocation densities.

  13. Effects of annealing temperature in a metal alloy nano-dot memory

    International Nuclear Information System (INIS)

    Lee, Jung Min; Lee, Gae Hun; Song, Yun Heub; Bea, Ji Cheol; Tanaka, Tetsu

    2011-01-01

    The annealing temperature dependence of the capacitance-voltage (C-V) characteristic has been studied in a metal-oxide semiconductor structure containing FePt nano-dots. Several in-situ annealing temperatures from 400 to ∼700 .deg. C in a high vacuum ambience (under 1 x 10 -5 Pa) were evaluated in view of the cell's characteristics and its reliability. Here, we demonstrate that the annealing temperature is significant for memory performance in an alloy metal nano-dot structure. A higher in-situ temperature provides better retention and a more reliable memory window. In the sample with an in-situ annealing condition of 700 .deg. C for 30 min, a memory window of 9.2 V at the initial stage was obtained, and a memory window of 6.2 V after 10 years was estimated, which is reliable for a non-volatile memory. From these results, the annealing condition for an alloy metal nano-dot memory is one of the critical parameters for the memory characteristics, and should be optimized for better memory performance.

  14. In vivo monitoring of toxic metals: assessment of neutron activation and x-ray fluorescence techniques

    International Nuclear Information System (INIS)

    Ellis, K.J.

    1986-01-01

    To date, cadmium, lead, aluminum, and mercury have been measured in vivo in humans. The possibilities of monitoring other toxic metals have also been demonstrated, but no human studies have been performed. Neutron activation analysis appears to be most suitable for Cd and Al measurements, while x-ray fluorescence is ideally suited for measurement of lead in superficial bone. Filtered neutron beams and polarized x-ray sources are being developed which will improve in vivo detection limits. Even so, several of the current facilities are already suitable for use in epidemiological studies of selected populations with suspected long-term low-level ''environmental'' exposures. Evaluation and diagnosis of patients presenting with general clinical symptoms attributable to possible toxic metal exposure may be assisted by in vivo examination. Continued in vivo monitoring of industrial workers, especially follow-up measurements, will provide the first direct assessment of changes in body burden and a direct measure of the biological life-times of these metals in humans. 50 refs., 4 figs., 2 tabs

  15. Molecular dynamics for near melting temperatures simulations of metals using modified embedded-atom method

    Science.gov (United States)

    Etesami, S. Alireza; Asadi, Ebrahim

    2018-01-01

    Availability of a reliable interatomic potential is one of the major challenges in utilizing molecular dynamics (MD) for simulations of metals at near the melting temperatures and melting point (MP). Here, we propose a novel approach to address this challenge in the concept of modified-embedded-atom (MEAM) interatomic potential; also, we apply the approach on iron, nickel, copper, and aluminum as case studies. We propose adding experimentally available high temperature elastic constants and MP of the element to the list of typical low temperature properties used for the development of MD interatomic potential parameters. We show that the proposed approach results in a reasonable agreement between the MD calculations of melting properties such as latent heat, expansion in melting, liquid structure factor, and solid-liquid interface stiffness and their experimental/computational counterparts. Then, we present the physical properties of mentioned elements near melting temperatures using the new MEAM parameters. We observe that the behavior of elastic constants, heat capacity and thermal linear expansion coefficient at room temperature compared to MP follows an empirical linear relation (α±β × MP) for transition metals. Furthermore, a linear relation between the tetragonal shear modulus and the enthalpy change from room temperature to MP is observed for face-centered cubic materials.

  16. New temperature monitoring devices for high-temperature irradiation experiments in the high flux reactor Petten

    Energy Technology Data Exchange (ETDEWEB)

    Laurie, M.; Futterer, M. A.; Lapetite, J. M. [European Commission Joint Research Centre, Institute for Energy, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Fourrez, S. [THERMOCOAX SAS, BP 26, Planquivon, 61438 Flers Cedex (France); Morice, R. [Laboratoire National de Metrologie et d' Essais, 1 rue Gaston Boissier, 75724 Paris (France)

    2009-07-01

    Within the European High Temperature Reactor Technology Network (HTR-TN) and related projects a number of HTR fuel irradiations are planned in the High Flux Reactor Petten (HFR), The Netherlands, with the objective to explore the potential of recently produced fuel for even higher temperature and burn-up. Irradiating fuel under defined conditions to extremely high burn-ups will provide a better understanding of fission product release and failure mechanisms if particle failure occurs. After an overview of the irradiation rigs used in the HFR, this paper sums up data collected from previous irradiation tests in terms of thermocouple data. Some research and development work for further improvement of thermocouples and other on-line instrumentation will be outlined. (authors)

  17. Monitoring Streambed Scour/Deposition Under Nonideal Temperature Signal and Flood Conditions

    Science.gov (United States)

    DeWeese, Timothy; Tonina, Daniele; Luce, Charles

    2017-12-01

    Streambed erosion and deposition are fundamental geomorphic processes in riverbeds, and monitoring their evolution is important for ecological system management and in-stream infrastructure stability. Previous research showed proof of concept that analysis of paired temperature signals of stream and pore waters can simultaneously provide monitoring scour and deposition, stream sediment thermal regime, and seepage velocity information. However, it did not address challenges often associated with natural systems, including nonideal temperature variations (low-amplitude, nonsinusoidal signal, and vertical thermal gradients) and natural flooding conditions on monitoring scour and deposition processes over time. Here we addressed this knowledge gap by testing the proposed thermal scour-deposition chain (TSDC) methodology, with laboratory experiments to test the impact of nonideal temperature signals under a range of seepage velocities and with a field application during a pulse flood. Both analyses showed excellent match between surveyed and temperature-derived bed elevation changes even under very low temperature signal amplitudes (less than 1°C), nonideal signal shape (sawtooth shape), and strong and changing vertical thermal gradients (4°C/m). Root-mean-square errors on predicting the change in streambed elevations were comparable with the median grain size of the streambed sediment. Future research should focus on improved techniques for temperature signal phase and amplitude extractions, as well as TSDC applications over long periods spanning entire hydrographs.

  18. Fabrication of Composite Microneedle Array Electrode for Temperature and Bio-Signal Monitoring

    Directory of Open Access Journals (Sweden)

    Yiwei Sun

    2018-04-01

    Full Text Available Body temperature and bio-signals are important health indicators that reflect the human health condition. However, monitoring these indexes is inconvenient and time-consuming, requires various instruments, and needs professional skill. In this study, a composite microneedle array electrode (CMAE was designed and fabricated. It simultaneously detects body temperature and bio-signals. The CMAE consists of a 6 × 6 microneedles array with a height of 500 μm and a base diameter of 200 μm. Multiple insertion experiments indicate that the CMAE possesses excellent mechanical properties. The CMAE can pierce porcine skin 100 times without breaking or bending. A linear calibration relationship between temperature and voltage are experimentally obtained. Armpit temperature (35.8 °C and forearm temperature (35.3 °C are detected with the CMAE, and the measurements agree well with the data acquired with a clinical thermometer. Bio-signals including EII, ECG, and EMG are recorded and compared with those obtained by a commercial Ag/AgCl electrode. The CMAE continuously monitors bio-signals and is more convenient to apply because it does not require skin preparation and gel usage. The CMAE exhibits good potential for continuous and repetitive monitoring of body temperature and bio-signals.

  19. Fabrication of Composite Microneedle Array Electrode for Temperature and Bio-Signal Monitoring.

    Science.gov (United States)

    Sun, Yiwei; Ren, Lei; Jiang, Lelun; Tang, Yong; Liu, Bin

    2018-04-13

    Body temperature and bio-signals are important health indicators that reflect the human health condition. However, monitoring these indexes is inconvenient and time-consuming, requires various instruments, and needs professional skill. In this study, a composite microneedle array electrode (CMAE) was designed and fabricated. It simultaneously detects body temperature and bio-signals. The CMAE consists of a 6 × 6 microneedles array with a height of 500 μm and a base diameter of 200 μm. Multiple insertion experiments indicate that the CMAE possesses excellent mechanical properties. The CMAE can pierce porcine skin 100 times without breaking or bending. A linear calibration relationship between temperature and voltage are experimentally obtained. Armpit temperature (35.8 °C) and forearm temperature (35.3 °C) are detected with the CMAE, and the measurements agree well with the data acquired with a clinical thermometer. Bio-signals including EII, ECG, and EMG are recorded and compared with those obtained by a commercial Ag/AgCl electrode. The CMAE continuously monitors bio-signals and is more convenient to apply because it does not require skin preparation and gel usage. The CMAE exhibits good potential for continuous and repetitive monitoring of body temperature and bio-signals.

  20. Tunable Diode Laser Sensors to Monitor Temperature and Gas Composition in High-Temperature Coal Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Ronald [Stanford Univ., CA (United States); Whitty, Kevin [Univ. of Utah, Salt Lake City, UT (United States)

    2014-12-01

    The integrated gasification combined cycle (IGCC) when combined with carbon capture and storage can be one of the cleanest methods of extracting energy from coal. Control of coal and biomass gasification processes to accommodate the changing character of input-fuel streams is required for practical implementation of integrated gasification combined-cycle (IGCC) technologies. Therefore a fast time-response sensor is needed for real-time monitoring of the composition and ideally the heating value of the synthesis gas (here called syngas) as it exits the gasifier. The goal of this project was the design, construction, and demonstration an in situ laserabsorption sensor to monitor multiple species in the syngas output from practical-scale coal gasifiers. This project investigated the hypothesis of using laser absorption sensing in particulateladen syngas. Absorption transitions were selected with design rules to optimize signal strength while minimizing interference from other species. Successful in situ measurements in the dusty, high-pressure syngas flow were enabled by Stanford’s normalized and scanned wavelength modulation strategy. A prototype sensor for CO, CH4, CO2, and H2O was refined with experiments conducted in the laboratory at Stanford University, a pilot-scale at the University of Utah, and an engineering-scale gasifier at DoE’s National Center for Carbon Capture with the demonstration of a prototype sensor with technical readiness level 6 in the 2014 measurement campaign.

  1. Comparison of Machining Temperature in High Speed Grinding of Metallic Materials and Brittle Materials

    Directory of Open Access Journals (Sweden)

    Wu Chongjun

    2017-01-01

    Full Text Available Grinding has always been a high energy expenditure process, which generally produce massive grinding heat and possibly produce thermal damage in workpiece ground surface. Therefore, a good understanding of grinding temperature characteristics is important to lower the thermal effect on the workpiece quality. However, the grinding temperature characteristic differs when grinding of different materials, especially for those hard-to-machine materials (eg. Titanium alloys and ceramics. Therefore, this paper is devoted to investigate different grinding temperature characteristics for metallic materials and brittle materials. In order to detect the grinding temperature, a grindable thermocouple technique with NI-DAQ device is adopted in diamond wheel grinding of ceramics and CBN grinding of Titanium alloys. The results show that the temperature characteristics for ceramics is totally different with Titanium alloys. When the grinding wheel speed increases, the grinding temperature increases all the way when grinding of Titanium alloys. However, there is a temperature turning point for grinding of ceramics. When the wheel speed surpasses the turning point, the grinding temperature goes down and closes at a relatively low temperature.

  2. Thermocouple and infrared sensor-based measurement of temperature distribution in metal cutting.

    Science.gov (United States)

    Kus, Abdil; Isik, Yahya; Cakir, M Cemal; Coşkun, Salih; Özdemir, Kadir

    2015-01-12

    In metal cutting, the magnitude of the temperature at the tool-chip interface is a function of the cutting parameters. This temperature directly affects production; therefore, increased research on the role of cutting temperatures can lead to improved machining operations. In this study, tool temperature was estimated by simultaneous temperature measurement employing both a K-type thermocouple and an infrared radiation (IR) pyrometer to measure the tool-chip interface temperature. Due to the complexity of the machining processes, the integration of different measuring techniques was necessary in order to obtain consistent temperature data. The thermal analysis results were compared via the ANSYS finite element method. Experiments were carried out in dry machining using workpiece material of AISI 4140 alloy steel that was heat treated by an induction process to a hardness of 50 HRC. A PVD TiAlN-TiN-coated WNVG 080404-IC907 carbide insert was used during the turning process. The results showed that with increasing cutting speed, feed rate and depth of cut, the tool temperature increased; the cutting speed was found to be the most effective parameter in assessing the temperature rise. The heat distribution of the cutting tool, tool-chip interface and workpiece provided effective and useful data for the optimization of selected cutting parameters during orthogonal machining.

  3. Thermocouple and Infrared Sensor-Based Measurement of Temperature Distribution in Metal Cutting

    Directory of Open Access Journals (Sweden)

    Abdil Kus

    2015-01-01

    Full Text Available In metal cutting, the magnitude of the temperature at the tool-chip interface is a function of the cutting parameters. This temperature directly affects production; therefore, increased research on the role of cutting temperatures can lead to improved machining operations. In this study, tool temperature was estimated by simultaneous temperature measurement employing both a K-type thermocouple and an infrared radiation (IR pyrometer to measure the tool-chip interface temperature. Due to the complexity of the machining processes, the integration of different measuring techniques was necessary in order to obtain consistent temperature data. The thermal analysis results were compared via the ANSYS finite element method. Experiments were carried out in dry machining using workpiece material of AISI 4140 alloy steel that was heat treated by an induction process to a hardness of 50 HRC. A PVD TiAlN-TiN-coated WNVG 080404-IC907 carbide insert was used during the turning process. The results showed that with increasing cutting speed, feed rate and depth of cut, the tool temperature increased; the cutting speed was found to be the most effective parameter in assessing the temperature rise. The heat distribution of the cutting tool, tool-chip interface and workpiece provided effective and useful data for the optimization of selected cutting parameters during orthogonal machining.

  4. Thermocouple and Infrared Sensor-Based Measurement of Temperature Distribution in Metal Cutting

    Science.gov (United States)

    Kus, Abdil; Isik, Yahya; Cakir, M. Cemal; Coşkun, Salih; Özdemir, Kadir

    2015-01-01

    In metal cutting, the magnitude of the temperature at the tool-chip interface is a function of the cutting parameters. This temperature directly affects production; therefore, increased research on the role of cutting temperatures can lead to improved machining operations. In this study, tool temperature was estimated by simultaneous temperature measurement employing both a K-type thermocouple and an infrared radiation (IR) pyrometer to measure the tool-chip interface temperature. Due to the complexity of the machining processes, the integration of different measuring techniques was necessary in order to obtain consistent temperature data. The thermal analysis results were compared via the ANSYS finite element method. Experiments were carried out in dry machining using workpiece material of AISI 4140 alloy steel that was heat treated by an induction process to a hardness of 50 HRC. A PVD TiAlN-TiN-coated WNVG 080404-IC907 carbide insert was used during the turning process. The results showed that with increasing cutting speed, feed rate and depth of cut, the tool temperature increased; the cutting speed was found to be the most effective parameter in assessing the temperature rise. The heat distribution of the cutting tool, tool-chip interface and workpiece provided effective and useful data for the optimization of selected cutting parameters during orthogonal machining. PMID:25587976

  5. A Shear Horizontal Waveguide Technique for Monitoring of High Temperature Pipe Thinning

    International Nuclear Information System (INIS)

    Cheong, Yongmoo; Kim, Hongpyo; Lee, Duckhyun

    2014-01-01

    An ultrasonic thickness measurement method is a well-known and most commonly used non-destructive testing technique for wall thickness monitoring of a piping or plate. However, current commonly available ultrasonic transducers cannot withstand high temperatures of, above 200 .deg. C. Currently, the variation of wall thickness of the pipes is determined by a portable ultrasonic gauge during plant shutdowns. This manual ultrasonic method reveals several disadvantages: inspections have to be performed during shutdowns with the possible consequences of prolonging down time and increasing production losses, insulation has to be removed and replaced for each manual measurement, and scaffolding has to be installed to inaccessible areas, resulting in considerable cost for intervention. In addition, differences of the measurement conditions such as examiner, temperature, and couplant could result in measurement errors. It has been suggested that a structural health monitoring approach with permanently installed ultrasonic thickness gauges could have substantial benefits over current practices. In order to solve those fundamental problems occurring during the propagation of ultrasound at high temperature, a shear horizontal waveguide technique for wall thickness monitoring at high temperatures is developed. A dry clamping device without a couplant for the acoustic contact between waveguide and pipe surface was designed and fabricated. The shear horizontal waveguides and clamping device result in an excellent S/N ratio and high accuracy of measurement with long exposure in an elevated temperature condition. A computer program for on-line monitoring of the pipe thickness at high temperature for a long period of time was developed. The system can be applied to monitor the FAC in carbon steel piping in a nuclear power plant after a verification test for a long period of time

  6. Process defects and in situ monitoring methods in metal powder bed fusion: a review

    Science.gov (United States)

    Grasso, Marco; Colosimo, Bianca Maria

    2017-04-01

    Despite continuous technological enhancements of metal Additive Manufacturing (AM) systems, the lack of process repeatability and stability still represents a barrier for the industrial breakthrough. The most relevant metal AM applications currently involve industrial sectors (e.g. aerospace and bio-medical) where defects avoidance is fundamental. Because of this, there is the need to develop novel in situ monitoring tools able to keep under control the stability of the process on a layer-by-layer basis, and to detect the onset of defects as soon as possible. On the one hand, AM systems must be equipped with in situ sensing devices able to measure relevant quantities during the process, a.k.a. process signatures. On the other hand, in-process data analytics and statistical monitoring techniques are required to detect and localize the defects in an automated way. This paper reviews the literature and the commercial tools for in situ monitoring of powder bed fusion (PBF) processes. It explores the different categories of defects and their main causes, the most relevant process signatures and the in situ sensing approaches proposed so far. Particular attention is devoted to the development of automated defect detection rules and the study of process control strategies, which represent two critical fields for the development of future smart PBF systems.

  7. Flash pyrolysis of heavy metal contaminated biomass from phytoremediation: Influence of temperature, entrained flow and wood/leaves blended pyrolysis on the behaviour of heavy metals

    OpenAIRE

    STALS, Mark; THIJSSEN, Elsy; VANGRONSVELD, Jaco; CARLEER, Robert; SCHREURS, Sonja; YPERMAN, Jan

    2010-01-01

    Phytoremediation crop disposal is a problem inhibiting the widespread use of the remediation technique. Flash pyrolysis as processing method for metal contaminated biomass is investigated: the rather low pyrolysis temperature prevents metal compounds from volatilisation while valuable pyrolysis oil is produced. Both plant stems and leaves are pyrolysed in a lab-scale semi-continuous reactor. Parameters under investigation are pyrolysis temperature (623, 723 and 823 K), the use of hot-gas filt...

  8. Effect of metal fragments in brain on electrical monitoring: In vitro and in vivo rat studies

    Science.gov (United States)

    Ahmed, A.; Bodo, M.; Armonda, R. A.

    2010-04-01

    Preliminary results showed, measurements by rheoencephalography (REG) very promising as a practical, noninvasive continuous monitoring modality of traumatic brain/blast injuries. As the impact of metal fragments on the REG signal is unknown, we report here results of our study .The in vitro study confirmed that impedance pulse amplitude waves do not change in the presence of metal (needles) placed between electrodes. In vivo studies: rats under anesthesia (10 rats, 101 trials) were measured after implantation of EEG and REG electrodes in the brain. Metal fragments were represented by 18 g needles inserted and removed between EEG and REG electrodes. Data were stored in a PC. EEG recording typically showed amplitude decrease; REG showed transitory amplitude increase after placement of a needle into either hemisphere. Removal of needles caused a decrease in REG amplitude after a transitory increase. The change in REG amplitude statistically was non-significant. Cerebral blood flow (CBF) autoregulation(AR) persisted following placement of metal fragments in rat brain.

  9. Intelligent Monitoring System With High Temperature Distributed Fiberoptic Sensor For Power Plant Combustion Processes

    Energy Technology Data Exchange (ETDEWEB)

    Kwang Y. Lee; Stuart S. Yin; Andre Boheman

    2005-12-26

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, we set up a dedicated high power, ultrafast laser system for fabricating in-fiber gratings in harsh environment optical fibers, successfully fabricated gratings in single crystal sapphire fibers by the high power laser system, and developed highly sensitive long period gratings (lpg) by electric arc. Under Task 2, relevant mathematical modeling studies of NOx formation in practical combustors. Studies show that in boiler systems with no swirl, the distributed temperature sensor may provide information sufficient to predict trends of NOx at the boiler exit. Under Task 3, we investigate a mathematical approach to extrapolation of the temperature distribution within a power plant boiler facility, using a combination of a modified neural network architecture and semigroup theory. The 3D temperature data is furnished by the Penn State Energy Institute using FLUENT. Given a set of empirical data with no analytic expression, we first develop an analytic description and then extend that model along a single axis. Extrapolation

  10. One-step fabrication of crystalline metal nanostructures by direct nanoimprinting below melting temperatures

    Science.gov (United States)

    Liu, Ze

    2017-03-01

    Controlled fabrication of metallic nanostructures plays a central role in much of modern science and technology, because changing the dimensions of a nanocrystal enables tailoring of its mechanical, electronic, optical, catalytic and antibacterial properties. Here we show direct superplastic nanoimprinting (SPNI) of crystalline metals well below their melting temperatures, generating ordered nanowire arrays with aspect ratios up to ~2,000 and imprinting features as small as 8 nm. Surface-enhanced Raman scattering (SERS) spectra reveal strongly enhanced electromagnetic signals from the prepared nanorod arrays with sizes up to ~100 nm, which indicates that our technique can provide an ideal way to fabricate robust SERS substrates. SPNI, as a one-step, controlled and reproducible nanofabrication method, could facilitate the applications of metal nanostructures in bio-sensing, diagnostic imaging, catalysis, food industry and environmental conservation.

  11. Glancing angle deposition of sculptured thin metal films at room temperature

    Science.gov (United States)

    Liedtke, S.; Grüner, Ch; Lotnyk, A.; Rauschenbach, B.

    2017-09-01

    Metallic thin films consisting of separated nanostructures are fabricated by evaporative glancing angle deposition at room temperature. The columnar microstructure of the Ti and Cr columns is investigated by high resolution transmission electron microscopy and selective area electron diffraction. The morphology of the sculptured metallic films is studied by scanning electron microscopy. It is found that tilted Ti and Cr columns grow with a single crystalline morphology, while upright Cr columns are polycrystalline. Further, the influence of continuous substrate rotation on the shaping of Al, Ti, Cr and Mo nanostructures is studied with view to surface diffusion and the shadowing effect. It is observed that sculptured metallic thin films deposited without substrate rotation grow faster compared to those grown with continuous substrate rotation. A theoretical model is provided to describe this effect.

  12. Combined effects of temperature changes and metal contamination at different levels of biological organization in yellow perch

    Energy Technology Data Exchange (ETDEWEB)

    Grasset, Julie [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6 (Canada); Ollivier, Élodie [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Bougas, Bérénice [Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6 (Canada); Yannic, Glenn [Laboratoire d’Écologie Alpine, UMR CNRS 5553, Université de Savoie Mont Blanc, 73376 Le Bourget-du-lac (France); Campbell, Peter G.C. [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Bernatchez, Louis [Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6 (Canada); Couture, Patrice, E-mail: patrice.couture@ete.inrs.ca [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada)

    2016-08-15

    Highlights: • Yellow perch were exposed to a combination of heat and metal (Cd or Ni) stress. • Kidney metal accumulation was greatly enhanced at higher temperatures. • Elevated temperatures negatively affected several indicators of condition and metabolic capacities. • Exposure to Ni stimulated gonad development. • Metal stress modified the normal response of antioxidant capacities and apoptosis to heat stress. - Abstract: In this study, we measured the effects of temperature (9 °C, 20 °C, and 28 °C), metal contamination (cadmium and nickel) and their interaction on yellow perch (Perca flavescens) using liver enzymatic and transcriptomic endpoints and biometric indices. Kidney metal concentrations increased with a rise of temperature. The biometric indices analysed (Fulton condition factor, pyloric cæca, hepatosomatic and gonadosomatic indices) generally decreased with an increase of temperature but not with metal contamination. At the enzymatic level, the activity of superoxide dismutase (SOD), involved in antioxidant response, was affected by both temperature and metal contamination, whereas the activity of glucose-6-phosphate dehydrogenase (G6PDH), involved in energy accumulation but also in antioxidant response, was only affected by metal exposure. The response of perch to the stressors at the transcriptional level differed from the metabolic response. In particular, the transcription level of the cco and g6pdh genes sharply decreased with increasing temperature, while the activities of the corresponding enzymes remained stable. The normal response of the transcription level of the apoptotic gene (diablo) to heat stress was also altered in metal-contaminated fish. The combination of metal and temperature stresses also modified the response of antioxidant metabolism induced by these stressors individually. This study contributes to a better understanding of the influences of natural stressors like temperature on biomarkers commonly used in

  13. Monitoring moisture content, temperature, and humidity in whole-tree pine chip piles

    Science.gov (United States)

    John Klepac; Dana Mitchell; Jason Thompson

    2015-01-01

    Two whole-tree chip piles were monitored for moisture content, temperature, and relative humidity from October 8th, 2010 to March 16th, 2011 at a location in south Alabama. Initial moisture content samples were collected immediately after chips were delivered to the study location on October 8th for Pile 1 and October 22nd for Pile 2. During pile construction, Lascar...

  14. Monitoring sea level and sea surface temperature trends from ERS satellites

    DEFF Research Database (Denmark)

    Andersen, Ole Baltazar; Knudsen, Per; Beckley, B.

    2002-01-01

    Data from the two ESA satellites ERS-1 and ERS-2 are used in global and regional analysis of sea level and sea surface temperature trends over the last, 7.8 years. T he ERS satellites and in the future the ENVISAT satellite provide unique opportunity for monitoring both changes in sea level and s...

  15. A microprocessor based, multi-channel low-temperature monitoring system

    NARCIS (Netherlands)

    Kuiper, B.W.; van Dijk, M.H.H.

    1982-01-01

    A multi-channel low-temperature monitoring system and its design considerations are presented. The system is microprocessor based and specially designed to interface thermoresistive sensors in cryogenic experiments. The system can be easily expanded to accept any type of physical transducer and to

  16. Influence of a Liquid Metal Temperature on a Thermal Decomposition of a Phenolic Resin

    Directory of Open Access Journals (Sweden)

    Holtzer M.

    2013-06-01

    Full Text Available Due to the presence of harmful substances in resins those mould sands may be hazardous to the natural environment and workers. The general assessment of harmfulness of sands used for molds and cores encompasses 2 basic points: emission of hazardous substances during processes of preparing sands, pouring mold with liquid metals (high temperatures, cooling and shaking-out; possibility of washing out hazardous substances from used sands to the environment, during storage or economic use outside foundries. We present the results of research on the emission of BTEX compounds from mould sands with phenolic resins during pouring liquid metal of different temperature (cast iron and Al alloy. The research was conducted according to the original method prepared by the authors, which has been used for years in cooperation with various foundries (Poland, abroad.

  17. A highly reversible room-temperature lithium metal battery based on crosslinked hairy nanoparticles.

    KAUST Repository

    Choudhury, Snehashis

    2015-12-04

    Rough electrodeposition, uncontrolled parasitic side-reactions with electrolytes and dendrite-induced short-circuits have hindered development of advanced energy storage technologies based on metallic lithium, sodium and aluminium electrodes. Solid polymer electrolytes and nanoparticle-polymer composites have shown promise as candidates to suppress lithium dendrite growth, but the challenge of simultaneously maintaining high mechanical strength and high ionic conductivity at room temperature has so far been unmet in these materials. Here we report a facile and scalable method of fabricating tough, freestanding membranes that combine the best attributes of solid polymers, nanocomposites and gel-polymer electrolytes. Hairy nanoparticles are employed as multifunctional nodes for polymer crosslinking, which produces mechanically robust membranes that are exceptionally effective in inhibiting dendrite growth in a lithium metal battery. The membranes are also reported to enable stable cycling of lithium batteries paired with conventional intercalating cathodes. Our findings appear to provide an important step towards room-temperature dendrite-free batteries.

  18. Hot metal temperature prediction and simulation by fuzzy logic in a blast furnace

    International Nuclear Information System (INIS)

    Romero, M. A.; Jimenez, J.; Mochon, J.; Formoso, A.; Bueno, F.; Menendez, J. L.

    2000-01-01

    This work describes the development and further validation of a model devoted to blast furnace hot metal temperature forecast, based on Fuzzy logic principles. The model employs as input variables, the control variables of an actual blast furnace: Blast volume, moisture, coal injection, oxygen addition, etc. and it yields as a result the hot metal temperature with a forecast horizon of forty minutes. As far as the variables used to develop the model have been obtained from data supplied by an actual blast furnaces sensors, it is necessary to properly analyse and handle such data. Especial attention was paid to data temporal correlation, fitting by interpolation the different sampling rates. In the training stage of the model the ANFIS (Adaptive Neuro-Fuzzy Inference System) and the Subtractive Clustering algorithms have been used. (Author) 9 refs

  19. General incorporation of diverse components inside metal-organic framework thin films at room temperature

    Science.gov (United States)

    Mao, Yiyin; Li, Junwei; Cao, Wei; Ying, Yulong; Hu, Pan; Liu, Yu; Sun, Luwei; Wang, Hongtao; Jin, Chuanhong; Peng, Xinsheng

    2014-11-01

    Porous metal-organic frameworks (MOFs) demonstrate great potential for numerous applications. Although hetero-functional components have been encapsulated within MOF crystalline particles, the uniform incorporation of functional species with different sizes, shapes and functions in MOF thin films with dual properties, especially at room temperature and without the degradation of the MOF framework, remains a significant challenge towards further enriching their functions for various purposes. Here we report a general method that can rapidly encapsulate diverse functional components, including small ions, micrometre-sized particles, inorganic nanoparticles and bioactive proteins, in MOF thin films at room temperature via a metal-hydroxide-nanostrand-assisted confinement technique. These functional component-encapsulated MOF composite thin films exhibit synergistic and size-selective catalytic, bio-electrochemical, conductive and flexible functionalities that are desirable for thin film devices, including catalytic membrane reactors, biosensors and flexible electronic devices.

  20. Fast Monitoring Soil Environmental Qualities of Heavy Metal by Portable X-Ray Fluorescence Spectrometer.

    Science.gov (United States)

    Wang, Bao; Yu, Jian-xin; Huang, Biao; Hu, Wen-you; Chang, Qing

    2015-06-01

    Portable X-ray fluorescence (PXRF) spectrometer as a new type of equipment for quick test has a prominent prospect, but there are also shortcomings of detection range and limition, therefore this paper studied the suitability of PXRF spectrometer in monitoring soil environmental qualities of heavy metals included Cr, Ni, Cu, Zn, Pb, Cd, As and Hg, the aim of this paper is to screen elements which can be detected by this kind of instrument and evaluate the accuracy of test results. The research method is to test heavy metals contaminated soil samples by PXRF spectrometer, evaluate the accuracy of test results of PXRF compared with inductively coupled plasma mass(ICP-MS), then establish linear regression relationship between analysis results of PXRF and ICP-MS method. The results show that, (1) When measuring the soil environmental quality, PXRF spectrometer is appropriate to measure the content of Pb, Zn, Cr and Cu, except Ni, Cd, As and Hg. (2) Compared with the test value of ICP-MS, the test value of Pb and Zn is lower, the test value of Cu is higher, the test value of Cr is too high, all the results of PXRF spectrometer should be linear corrected according to standard analysis method. In conclusion, PXRF spectrometer is suitable for monitoring environmental quality of soil which is polluted by heavy metal such as Pb, Zn, Cr and Cu, it is an analysis means with characteristics of simple and rapid, accurate and reliable. The innovation of this article is that reasonable avoiding the shortcomings of PXRF spectrometer as using the instrument to monitor soil environmental quality, at last improved the application value of test results.

  1. High-Temperature Fatigue of a Hybrid Aluminum Metal Matrix Composite

    Science.gov (United States)

    Clark, J. T.; Sanders, P. G.

    2014-01-01

    An aluminum metal matrix composite (MMC) brake drum was tested in fatigue at room temperature and extreme service temperatures. At room temperature, the hybrid composite did not fail and exceeded estimated vehicle service times. At higher temperatures (62 and 73 pct of the matrix eutectic), fatigue of a hybrid particle/fiber MMC exhibited failure consistent with matrix overloading. Overaging of the A356 matrix coupled with progressive fracture of the SiC particles combined to create the matrix overload condition. No evidence of macro-fatigue crack initiation or growth was observed, and the matrix-particle interface appeared strong with no debonding, visible matrix phases, or porosity. An effective medium model was constructed to test the hypothesis that matrix overloading was the probable failure mode. The measured particle fracture rate was fit using realistic values of the SiC Weibull strength and modulus, which in turn predicted cycles to failure within the range observed in fatigue testing.

  2. Monitoring of temperature profiles and surface morphologies during laser sintering of alumina ceramics

    Directory of Open Access Journals (Sweden)

    Bin Qian

    2014-06-01

    Full Text Available Additive manufacturing of alumina by laser is a delicate process and small changes of processing parameters might cause less controlled and understood consequences. The real-time monitoring of temperature profiles, spectrum profiles and surface morphologies were evaluated in off-axial set-up for controlling the laser sintering of alumina ceramics. The real-time spectrometer and pyrometer were used for rapid monitoring of the thermal stability during the laser sintering process. An active illumination imaging system successfully recorded the high temperature melt pool and surrounding area simultaneously. The captured images also showed how the defects form and progress during the laser sintering process. All of these real-time monitoring methods have shown a great potential for on-line quality control during laser sintering of ceramics.

  3. Documentation pckage for the RFID temperature monitoring system (Of Model 9977 packages at NTS).

    Energy Technology Data Exchange (ETDEWEB)

    Chen, K.; Tsai, H.; Decision and Information Sciences

    2009-02-20

    The technical basis for extending the Model 9977 shipping package periodic maintenance beyond the one-year interval to a maximum of five years is based on the performance of the O-ring seals and the environmental conditions. The DOE Packaging Certification Program (PCP) has tasked Argonne National Laboratory to develop a Radio-Frequency Identification (RFID) temperature monitoring system for use by the facility personnel at DAF/NTS. The RFID temperature monitoring system, depicted in the figure below, consists of the Mk-1 RFId tags, a reader, and a control computer mounted on a mobile platform that can operate as a stand-alone system, or it can be connected to the local IT network. As part of the Conditions of Approval of the CoC, the user must complete the prescribed training to become qualified and be certified for operation of the RFID temperature monitoring system. The training course will be administered by Argonne National Laboratory on behalf of the Headquarters Certifying Official. This is a complete documentation package for the RFID temperature monitoring system of the Model 9977 packagings at NTS. The documentation package will be used for training and certification. The table of contents are: Acceptance Testing Procedure of MK-1 RFID Tags for DOE/EM Nuclear Materials Management Applications; Acceptance Testing Result of MK-1 RFID Tags for DOE/EM Nuclear Materials Management Applications; Performance Test of the Single Bolt Seal Sensor for the Model 9977 Packaging; Calibration of Built-in Thermistors in RFID Tags for Nevada Test Site; Results of Calibration of Built-in Thermistors in RFID Tags; Results of Thermal Calibration of Second Batch of MK-I RFID Tags; Procedure for Installing and Removing MK-1 RFID Tag on Model 9977 Drum; User Guide for RFID Reader and Software for Temperature Monitoring of Model 9977 Drums at NTS; Software Quality Assurance Plan (SQAP) for the ARG-US System; Quality Category for the RFID Temperature Monitoring System; The

  4. Documentation package for the RFID temperature monitoring system (Model 9977 packages at NTS)

    International Nuclear Information System (INIS)

    Chen, K.; Tsai, H.

    2009-01-01

    The technical basis for extending the Model 9977 shipping package periodic maintenance beyond the one-year interval to a maximum of five years is based on the performance of the O-ring seals and the environmental conditions. The DOE Packaging Certification Program (PCP) has tasked Argonne National Laboratory to develop a Radio-Frequency Identification (RFID) temperature monitoring system for use by the facility personnel at DAF/NTS. The RFID temperature monitoring system, depicted in the figure below, consists of the Mk-1 RFId tags, a reader, and a control computer mounted on a mobile platform that can operate as a stand-alone system, or it can be connected to the local IT network. As part of the Conditions of Approval of the CoC, the user must complete the prescribed training to become qualified and be certified for operation of the RFID temperature monitoring system. The training course will be administered by Argonne National Laboratory on behalf of the Headquarters Certifying Official. This is a complete documentation package for the RFID temperature monitoring system of the Model 9977 packagings at NTS. The documentation package will be used for training and certification. The table of contents are: Acceptance Testing Procedure of MK-1 RFID Tags for DOE/EM Nuclear Materials Management Applications; Acceptance Testing Result of MK-1 RFID Tags for DOE/EM Nuclear Materials Management Applications; Performance Test of the Single Bolt Seal Sensor for the Model 9977 Packaging; Calibration of Built-in Thermistors in RFID Tags for Nevada Test Site; Results of Calibration of Built-in Thermistors in RFID Tags; Results of Thermal Calibration of Second Batch of MK-I RFID Tags; Procedure for Installing and Removing MK-1 RFID Tag on Model 9977 Drum; User Guide for RFID Reader and Software for Temperature Monitoring of Model 9977 Drums at NTS; Software Quality Assurance Plan (SQAP) for the ARG-US System; Quality Category for the RFID Temperature Monitoring System; The

  5. Imaging technique for real-time temperature monitoring during cryotherapy of lesions

    Science.gov (United States)

    Petrova, Elena; Liopo, Anton; Nadvoretskiy, Vyacheslav; Ermilov, Sergey

    2016-11-01

    Noninvasive real-time temperature imaging during thermal therapies is able to significantly improve clinical outcomes. An optoacoustic (OA) temperature monitoring method is proposed for noninvasive real-time thermometry of vascularized tissue during cryotherapy. The universal temperature-dependent optoacoustic response (ThOR) of red blood cells (RBCs) is employed to convert reconstructed OA images to temperature maps. To obtain the temperature calibration curve for intensity-normalized OA images, we measured ThOR of 10 porcine blood samples in the range of temperatures from 40°C to -16°C and analyzed the data for single measurement variations. The nonlinearity (ΔTmax) and the temperature of zero OA response (T0) of the calibration curve were found equal to 11.4±0.1°C and -13.8±0.1°C, respectively. The morphology of RBCs was examined before and after the data collection confirming cellular integrity and intracellular compartmentalization of hemoglobin. For temperatures below 0°C, which are of particular interest for cryotherapy, the accuracy of a single temperature measurement was ±1°C, which is consistent with the clinical requirements. Validation of the proposed OA temperature imaging technique was performed for slow and fast cooling of blood samples embedded in tissue-mimicking phantoms.

  6. Prediction of creep of metallic materials under time-variable temperatures and stresses

    International Nuclear Information System (INIS)

    Batsoulas, N.D.

    1994-01-01

    A method is presented for the prediction of metallic materials creep behaviour at time-variable temperatures, exclusively with creep input data under constant loading. The method is derived from a more general physical-phenomenological model and, additionally, incorporates the prediction under time-variable stresses. To test the method's predicting capability, a series of experiments was carried out for the creep strain at time-variable temperatures and stresses for austenitic steel X8CrNiMoNb 16-16. The test data were predicted reasonably well using the method in question. (orig.) [de

  7. Effect of temperature on heavy metal toxicity to earthworm Lumbricus terrestris (Annelida: Oligochaeta).

    Science.gov (United States)

    Khan, M A Q; Ahmed, S A; Salazar, A; Gurumendi, J; Khan, A; Vargas, M; von Catalin, B

    2007-10-01

    Earthworms (Lumbricus terrestris) acclimated at 2 degrees C above their habitat temperature (10-12 degrees C) showed about 5% increase in basal rate of oxygen consumption, which increased to about 38% in 14-16 degrees C- and 40% in 16-18 degrees C-, but decreased by 84% in 20-22 degrees C-acclimated worms. Temperature also increased the blood hemoglobin (Hb) concentration, which decreased slightly in 20-22 degrees C-acclimated worms. The worms acclimated at 20-22 degrees C showed their blood to be hypovolemic than that of 10-12 degrees C worms indicating dehydration. Pre-exposure of 10-14 degrees C-acclimated worms to sublethal concentrations of zinc, copper, and lead did not significantly affect the rate of respiration. However, at higher temperatures all these metals inhibited oxygen consumption; zinc, lead, and cadmium by approximately 11% and copper by approximately 18% of that at 14-16 degrees C. At 20-22 degrees C, the respiration was further inhibited, 36% by copper, 18% by cadmium, and approximately 10% by lead and zinc. Copper, lead, and zinc decreased the temperature-enhanced increase in blood Hb concentration at all temperatures. In 20-22 degrees C-acclimated worms heavy metal exposure slightly lowered the oxygen affinity of Hb as well as caused shifts in carbon monoxide difference spectra. The acute toxicity of these metals was not affected by a 2 degrees C rise in acclimation temperature but increased by 17% (lead), 33% (copper), and 5% (zinc) in 14-16 degrees C- and by 40% (lead), 149% (copper), and 132% (zinc) in 20-22 degrees C-acclimated worms. The increase in toxicity of metals caused by high temperatures may be due to limiting the scope of aerobic metabolism (oxygen extraction, transport, and utilization) via quantitative and qualitative effects on Hb. This terrestrial species appears to be tolerant of slight increases in habitat temperature, such as that expected with current global climate change. 2007 Wiley Periodicals, Inc.

  8. SXR Continuum Radiation Transmitted Through Metallic Filters: An Analytical Approach To Fast Electron Temperature Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Delgado-Aparicio, L.; Tritz, K.; Kramer, T.; Stutman, D.; Finkentha, M.; Hill, K.; Bitter, M.

    2010-08-26

    A new set of analytic formulae describes the transmission of soft X-ray (SXR) continuum radiation through a metallic foil for its application to fast electron temperature measurements in fusion plasmas. This novel approach shows good agreement with numerical calculations over a wide range of plasma temperatures in contrast with the solutions obtained when using a transmission approximated by a single-Heaviside function [S. von Goeler, Rev. Sci. Instrum., 20, 599, (1999)]. The new analytic formulae can improve the interpretation of the experimental results and thus contribute in obtaining fast teperature measurements in between intermittent Thomson Scattering data.

  9. Metal glass vacuum tube solar collectors are approaching lower-medium temperature heat application.

    Science.gov (United States)

    Jiang, Xinian

    2010-04-26

    Solar thermal collectors are widely used worldwide mainly for hot water preparation at a low temperature (less than 80?C). Applications including many industrial processes and central air conditioning with absorption chillers, instead require lower-medium temperature heat (between 90 degrees C and 150 degrees C) to be driven when using solar thermal energy. The metal absorber glass vacuum tube collectors (MGVT) are developed for this type of applications. Current state-of-art and possible future technology development of MGVT are presented.

  10. Ambient-temperature superconductor symetrical metal-dihalide bis-(ethylenedithio)-tetrathiafulvalene compounds

    Science.gov (United States)

    Williams, Jack M.; Wang, Hsien-Hau; Beno, Mark A.

    1987-01-01

    A new class of organic superconductors having the formula (ET).sub.2 MX.sub.2 wherein ET represents bis(ethylenedithio)-tetrathiafulvalene, M is a metal such as Au, Ag, In, Tl, Rb, Pd and the like and X is a halide. The superconductor (ET).sub.2 AuI.sub.2 exhibits a transition temperature of 5 K. which is high for organic superconductors.

  11. Creep of crystals: High-temperature deformation processes in metals, ceramics and minerals

    Science.gov (United States)

    Poirier, J. P.

    An introductory text describing high-temperature deformation processes in metals, ceramics, and minerals is presented. Among the specific topics discussed are: the mechanical aspects of crystal deformation; lattice defects; and phenomenological and thermodynamical analysis of quasi-steady-state creep. Consideration is also given to: dislocation creep models; the effect of hydrostatic pressure on deformation; creep polygonization; and dynamic recrystallization. The status of experimental techniques for the study of transformation plasticity in crystals is also discussed.

  12. Substrate temperature control for the formation of metal nanohelices by glancing angle deposition

    International Nuclear Information System (INIS)

    Sumigawa, Takashi; Sakurai, Atsushi; Iwata, Kazuya; Chen, Shaoguang; Kitamura, Takayuki; Tanie, Hisashi

    2015-01-01

    The targets of this study are to develop a device to precisely control the temperature during glancing angle deposition, to make films consisting of low melting temperature metal nanoelements with a controlled shape (helix), and to explore the substrate temperature for controlling the nanoshapes. A vacuum evaporation system capable of both cooling a substrate and measurement of its temperature was used to form thin films consisting of arrays of Cu and Al nanohelices on silicon substrates by maintaining the substrate temperature at T s /T m  < 0.22 (T s is the substrate temperature and T m is the melting temperature of target material). The critical T s /T m to produce Cu and Al nanohelices corresponds to the transitional homologous temperature between zones I and II in the structure zone model for the solid film, where surface diffusion becomes dominant. X-ray diffraction analysis indicated that the Cu and Al nanohelix thin films were composed of coarse oriented grains with diameters of several tens of nanometers

  13. Niphargus: a silicon band-gap sensor temperature logger for high-precision environmental monitoring

    Science.gov (United States)

    Burlet, Christian; Vanbrabant, Yves; Piessens, Kris; Welkenhuysen, Kris; Verheyden, Sophie

    2014-05-01

    A temperature logger, called 'Niphargus', was developed at the Geological Survey of Belgium to monitor temperature of local natural processes with sensitivity of the order of a few hundredths of degrees to monitor temperature variability in open air, caves, soils and rivers. The newly developed instrument uses a state-of-the-art band-gap silicon temperature sensor with digital output. This sensor reduces the risk of drift associated with thermistor-based sensing devices, especially in humid environments. The Niphargus is designed to be highly reliable, low-cost and powered by a single lithium cell with up to several years autonomy depending on the sampling rate and environmental conditions. The Niphargus was evaluated in an ice point bath experiment in terms of temperature accuracy and thermal inertia. The small size and low power consumption of the logger allow its use in difficult accessible environments, e.g. caves and space-constrained applications, inside a rock in a water stream. In both cases, the loggers have proven to be reliable and accurate devices. For example, spectral analysis of the temperature signal in the Han caves (Belgium) allowed detection and isolation of a 0.005° C amplitude day-night periodic signal in the temperature curve. PIC Figure 1: a Niphargus logger in its standard size. SMD components side. Photo credit: W. Miseur

  14. Monitoring and Control of the Hybrid Laser-Gas Metal-Arc Welding Process

    Energy Technology Data Exchange (ETDEWEB)

    Kunerth, D. C.; McJunkin, T. R.; Nichol, C. I.; Clark, D.; Todorov, E.; Couch, R. D.; Yu, F.

    2013-07-01

    Methods are currently being developed towards a more robust system real time feedback in the high throughput process combining laser welding with gas metal arc welding. A combination of ultrasonic, eddy current, electronic monitoring, and visual techniques are being applied to the welding process. Initial simulation and bench top evaluation of proposed real time techniques on weld samples are presented along with the concepts to apply the techniques concurrently to the weld process. Consideration for the eventual code acceptance of the methods and system are also being researched as a component of this project. The goal is to detect defects or precursors to defects and correct when possible during the weld process.

  15. Temperature and Burnup Correlated FCCI in U-10Zr Metallic Fuel

    Energy Technology Data Exchange (ETDEWEB)

    William J. Carmack

    2012-05-01

    Metallic fuels are proposed for use in advanced sodium cooled fast reactors. The experience basis for metallic fuels is extensive and includes development and qualification of fuels for the Experimental Breeder Reactor I, the Experimental Breeder Reactor II, FERMI-I, and the Fast Flux Test Facility (FFTF) reactors. Metallic fuels provide a number of advantages over other fuel types in terms of fabricability, performance, recyclability, and safety. Key to the performance of all nuclear fuel systems is the resistance to “breach” and subsequent release of fission products and fuel constituents to the primary coolant system of the nuclear power plant. In metallic fuel, the experience is that significant fuel-cladding chemical (FCCI) interaction occurs and becomes prevalent at high power-high temperature operation and ultimately leads to fuel pin breach and failure. Empirical relationships for metallic fuel pin failure have been developed from a large body of in-pile and out of pile research, development, and experimentation. It has been found that significant in-pile acceleration of the FCCI rate is experienced over similar condition out-of-pile experiments. The study of FCCI in metallic fuels has led to the quantification of in-pile failure rates to establish an empirical time and temperature dependent failure limit for fuel elements. Up until now the understanding of FCCI layer formation has been limited to data generated in EBR-II experiments. This dissertation provides new FCCI data extracted from the MFF-series of metallic fuel irradiations performed in the FFTF. These fuel assemblies contain valuable information on the formation of FCCI in metallic fuels at a variety of temperature and burnup conditions and in fuel with axial fuel height three times longer than EBR-II experiments. The longer fuel column in the FFTF and the fuel pins examined have significantly different flux, power, temperature, and FCCI profiles than that found in similar tests conducted in

  16. Process Simulation of Aluminium Sheet Metal Deep Drawing at Elevated Temperatures

    International Nuclear Information System (INIS)

    Winklhofer, Johannes; Trattnig, Gernot; Lind, Christoph; Sommitsch, Christof; Feuerhuber, Hannes

    2010-01-01

    Lightweight design is essential for an economic and environmentally friendly vehicle. Aluminium sheet metal is well known for its ability to improve the strength to weight ratio of lightweight structures. One disadvantage of aluminium is that it is less formable than steel. Therefore complex part geometries can only be realized by expensive multi-step production processes. One method for overcoming this disadvantage is deep drawing at elevated temperatures. In this way the formability of aluminium sheet metal can be improved significantly, and the number of necessary production steps can thereby be reduced. This paper introduces deep drawing of aluminium sheet metal at elevated temperatures, a corresponding simulation method, a characteristic process and its optimization. The temperature and strain rate dependent material properties of a 5xxx series alloy and their modelling are discussed. A three dimensional thermomechanically coupled finite element deep drawing simulation model and its validation are presented. Based on the validated simulation model an optimised process strategy regarding formability, time and cost is introduced.

  17. A chemical approach toward low temperature alloying of immiscible iron and molybdenum metals

    Energy Technology Data Exchange (ETDEWEB)

    Nazir, Rabia [Department of Chemistry, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Applied Chemistry Research Centre, Pakistan Council of Scientific and Industrial Research Laboratories Complex, Lahore 54600 (Pakistan); Ahmed, Sohail [Department of Chemistry, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Mazhar, Muhammad, E-mail: mazhar42pk@yahoo.com [Department of Chemistry, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia); Akhtar, Muhammad Javed; Siddique, Muhammad [Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan); Khan, Nawazish Ali [Material Science Laboratory, Department of Physics, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Shah, Muhammad Raza [HEJ Research Institute of Chemistry, University of Karachi, Karachi 75270 (Pakistan); Nadeem, Muhammad [Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan)

    2013-11-15

    Graphical abstract: - Highlights: • Low temperature pyrolysis of [Fe(bipy){sub 3}]Cl{sub 2} and [Mo(bipy)Cl{sub 4}] homogeneous powder. • Easy low temperature alloying of immiscible metals like Fe and Mo. • Uniform sized Fe–Mo nanoalloy with particle size of 48–68 nm. • Characterization by EDXRF, AFM, XRPD, magnetometery, {sup 57}Fe Mössbauer and impedance. • Alloy behaves as almost superparamagnetic obeying simple –R(CPE)– circuit. - Abstract: The present research is based on a low temperature operated feasible method for the synthesis of immiscible iron and molybdenum metals’ nanoalloy for technological applications. The nanoalloy has been synthesized by pyrolysis of homogeneous powder precipitated, from a common solvent, of the two complexes, trisbipyridineiron(II)chloride, [Fe(bipy){sub 3}]Cl{sub 2}, and bipyridinemolybedenum(IV) chloride, [Mo(bipy)Cl{sub 4}], followed by heating at 500 °C in an inert atmosphere of flowing argon gas. The resulting nanoalloy has been characterized by using EDXRF, AFM, XRD, magnetometery, {sup 57}Fe Mössbauer and impedance spectroscopies. These results showed that under provided experimental conditions iron and molybdenum metals, with known miscibility barrier, alloy together to give (1:1) single phase material having particle size in the range of 48–66 nm. The magnetism of iron is considerably reduced after alloy formation and shows its trend toward superparamagnetism. The designed chemical synthetic procedure is equally feasible for the fabrication of other immiscible metals.

  18. Intelligent Monitoring System with High Temperature Distributed Fiberoptic Sensor for Power Plant Combustion Processes

    Energy Technology Data Exchange (ETDEWEB)

    Kwang Y. Lee; Stuart S. Yin; Andre Boehman

    2006-09-26

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, we have set up a dedicated high power, ultrafast laser system for fabricating in-fiber gratings in harsh environment optical fibers, successfully fabricated gratings in single crystal sapphire fibers by the high power laser system, and developed highly sensitive long period gratings (lpg) by electric arc. Under Task 2, relevant mathematical modeling studies of NOx formation in practical combustors have been completed. Studies show that in boiler systems with no swirl, the distributed temperature sensor may provide information sufficient to predict trends of NOx at the boiler exit. Under Task 3, we have investigated a mathematical approach to extrapolation of the temperature distribution within a power plant boiler facility, using a combination of a modified neural network architecture and semigroup theory. Given a set of empirical data with no analytic expression, we first developed an analytic description and then extended that model along a single axis.

  19. Monitoring the body temperature of cows and calves using video recordings from an infrared thermography camera.

    Science.gov (United States)

    Hoffmann, Gundula; Schmidt, Mariana; Ammon, Christian; Rose-Meierhöfer, Sandra; Burfeind, Onno; Heuwieser, Wolfgang; Berg, Werner

    2013-06-01

    The aim of this study was to assess the variability of temperatures measured by a video-based infrared camera (IRC) in comparison to rectal and vaginal temperatures. The body surface temperatures of cows and calves were measured contactless at different body regions using videos from the IRC. Altogether, 22 cows and 9 calves were examined. The differences of the measured IRC temperatures among the body regions, i.e. eye (mean: 37.0 °C), back of the ear (35.6 °C), shoulder (34.9 °C) and vulva (37.2 °C), were significant (P infrared thermography videos has the advantage to analyze more than 1 picture per animal in a short period of time, and shows potential as a monitoring system for body temperatures in cattle.

  20. Temperature monitoring with FBG sensor during diffuser-assisted laser-induced interstitial thermotherapy (Conference Presentation)

    Science.gov (United States)

    Pham, Ngot T.; Lee, Seul Lee; Lee, Yong Wook; Kang, Hyun Wook

    2017-02-01

    Temperature variations are often monitored by using sensors operating at the site of treatment during Laser-induced Interstitial Thermotherapy (LITT). Currently, temperature measurements during LITT have been performed with thermocouples (TCs). However, TCs could directly absorb laser light and lead to self-heating (resulting in an over-estimation). Fiber Bragg grating (FBG) sensors can instead overcome this limitation of the TCs due to its insensitivity to electromagnetic interference. The aim of the current study was to quantitatively evaluate the FBG temperature sensor with a K-type thermocouple to real-time monitor temperature increase in ex vivo tissue during diffuser-assisted LITT. A 4-W 980-nm laser was employed to deliver optical energy in continuous mode through a 600-µm core-diameter diffusing applicator. A goniometric measurement validated the uniform light distribution in polar and longitudinal directions. The FBG sensor showed a linear relationship (R2 = 0.995) between wavelength shift and temperature change in air and tissue along with a sensitivity of 0.0114 nm/˚C. Regardless of sensor type, the measured temperature increased with irradiation time and applied power but decreased with increasing distance from the diffuser surface. The temperature elevation augmented the degree of thermal coagulation in the tissue during LITT (4.0±0.3-mm at 99˚C after 120-s). The temperature elevation augmented the degree of thermal coagulation in the tissue during LITT s irradiation). The FBG-integrated diffuser was able to monitor the interstitial temperature in tubular tissue (porcine urethra) real-time during laser treatment. However, the thermal coagulation thickness of the porcine urethra was measured to be 1.5 mm that was slightly thicker ( 20%) than that of the bovine liver after 4-W 980-nm laser for 48 s. The FBG temperature sensor can be a feasible tool to real-time monitor the temporal development of the temperature during the diffuser-assisted LITT to

  1. Effect of temperature, solvent and nature of metal cations on the potentiometric titration S of iron oxide

    International Nuclear Information System (INIS)

    Tasleem, S.; Ishrat, B.

    2008-01-01

    A comprehensive study of the potentiometric titrations of iron oxide in the presence of CU/sub 2/ and Mg/sup 2/ were under taken under different experimental conditions of temperature and concentration of metal ions in aqueous and aqueous/organic mixed solvent. The adsorption of both the metal ions were observed to increase with the increase in pH and temperature of the system. The adsorbent iron oxide preferentially adsorbs transition metal as compared to alkaline earth metal ion. (author)

  2. Spatio-temporal behavior of brightness temperature in Tel-Aviv and its application to air temperature monitoring.

    Science.gov (United States)

    Pelta, Ran; Chudnovsky, A Alexandra; Schwartz, Joel

    2016-01-01

    This study applies remote sensing technology to assess and examine the spatial and temporal Brightness Temperature (BT) profile in the city of Tel-Aviv, Israel over the last 30 years using Landsat imagery. The location of warmest and coldest zones are constant over the studied period. Distinct diurnal and temporal BT behavior divide the city into four different segments. As an example of future application, we applied mixed regression models with daily random slopes to correlate Landsat BT data with monitored air temperature (Tair) measurements using 14 images for 1989-2014. Our preliminary results show a good model performance with R(2) = 0.81. Furthermore, based on the model's results, we analyzed the spatial profile of Tair within the study domain for representative days. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. The spatial and temporal behavior of brightness temperature in Tel-Aviv and its application to air temperature monitoring

    Science.gov (United States)

    Pelta, Ran; Chudnovsky, A. Alexandra; Schwarts, Joel

    2016-01-01

    This study applies remote sensing technology to assess and examine the spatial and temporal Brightness Temperature (BT) profile in the city of Tel-Aviv, Israel over the last 30 years using Landsat imagery. The location of warmest and coldest zones are constant over the studied period. Distinct diurnal and temporal BT behavior divide the city into four different segments. As an example of future application, we applied mixed regression models with daily random slopes to correlate Landsat BT data with monitored air temperature (Tair) measurements using 14 images for 1989–2014. Our preliminary results show a good model performance with R2 = 0.81. Furthermore, based on the model’s results, we analyzed the spatial profile of Tair within the study domain for representative days. PMID:26499933

  4. Utility of esophageal temperature monitoring during pulmonary vein isolation for atrial fibrillation using duty-cycled phased radiofrequency ablation.

    Science.gov (United States)

    Deneke, Thomas; Bünz, Kathrin; Bastian, Annely; Päsler, Marcus; Anders, Helge; Lehmann, Rainer; Meuser, Wolfgang; de Groot, Joris R; Horlitz, Marc; Haberkorn, Ron; Mügge, Andreas; Shin, Dong-In

    2011-03-01

    A novel ablation system has been introduced for rapid treatment of atrial fibrillation (AF). This system delivers duty-cycled phased radiofrequency (RF) energy via an over-the-wire catheter (PVAC® , Medtronic) to achieve pulmonary vein (PV) isolation. Lower power and depth control suggests that collateral damage might be minimized. However, no studies have investigated the potential for thermal effect and damage to the esophagus. Ninety consecutive patients undergoing PV-isolation were evaluated. Group A (48 patients) had continuous luminal esophageal temperature (LET) monitoring using a temperature probe with 3 metal electrodes located in the vicinity of the targeted PV ostia. Ablation ceased when LET exceeded 40 °C. Only patients with LET ≥ 39 °C underwent endoscopic evaluation to assess esophageal damage. Group B (42 patients) excluded LET monitoring but all patients underwent endoscopy. In Group A, 27 (56%) patients showed LET ≥ 39 °C (mean LET 40.5 °C). Endoscopy revealed esophageal alterations in 5 (8%) (3 erythema and 2 intramural bleeding). One hundred eighty-nine out of 190 (99.5%) targeted PVs were successfully isolated, with 1 PV unsuccessful due to high LET. In Group B all 165 targeted PVs (100%) were successfully isolated. Endoscopy in Group 2 revealed no esophageal alterations. Using a duty-cycled, phased RF ablation system is safe and effective to isolate PVs. No Eso alteration was documented after ablation when LET was not monitored. This suggests that the LET probe may contribute to the thermal effect. Whether the documented increments in LET are due to direct tissue heating or possible interaction between the LET probe requires further investigation. © 2010 Wiley Periodicals, Inc.

  5. Core Temperature Monitoring in Obstetric Spinal Anesthesia Using an Ingestible Telemetric Sensor.

    Science.gov (United States)

    du Toit, Leon; van Dyk, Dominique; Hofmeyr, Ross; Lombard, Carl J; Dyer, Robert A

    2018-01-01

    Perioperative hypothermia may affect maternal and neonatal outcomes after obstetric spinal anesthesia. Core temperature is often poorly monitored during spinal anesthesia, due to the lack of an accurate noninvasive core temperature monitor. The aim of this study was to describe core temperature changes and temperature recovery during spinal anesthesia for elective cesarean delivery. We expected that obstetric spinal anesthesia would be associated with a clinically relevant thermoregulatory insult (core temperature decrease >1.0°C). A descriptive study was conducted in 28 women. An ingestible telemetric temperature sensor was used to record core temperature over time (measured every 10 seconds). The primary outcome was the maximum core temperature decrease after spinal anesthetic injection. The secondary outcomes were lowest absolute core temperature, time to lowest temperature, time to recovery of core temperature, hypothermic exposure (degree-hours below 37.0°C), and the time-weighted hypothermic exposure (median number of degrees below 37.0°C per hour). Basic descriptive statistics, median spline smooth, and integration of the area below the 37.0°C line of the temperature-over-time curve were utilized to analyze the data. Intestinal temperature decreased by a mean (standard deviation) of 1.30°C (0.31); 99% confidence interval (CI), 1.14 to 1.46 after spinal anesthetic injection. The median (interquartile range [IQR]) time to temperature nadir was 0.96 (0.73-1.32) hours (95% CI, 0.88-1.22). Fourteen of the 28 participants experienced intestinal temperatures below 36.0°C after spinal injection. Temperature was monitored for a minimum of 8 hours after spinal injection. In 8 of 28 participants, intestinal temperature did not recover to baseline during the monitored period. A median (IQR) of 4.59 (3.38-5.92) hours (95% CI, 3.45-5.90) was required for recovery to baseline intestinal temperature in the remaining 20 patients. Participants experienced a median (IQR

  6. PARAMETRICAL IDENTIFICATION OF DIFFERENTIAL-DIFFERENCE HEAT TRANSFER MODEL DURING LIDAR TEMPERATURE MONITORING

    Directory of Open Access Journals (Sweden)

    K. A. Klyukvin

    2017-01-01

    Full Text Available The paper deals with the parametrical identification method of differential-difference heat transfer models during determining of lidar temperature condition. The problem is solved for enclosure external flange that is the most thermally influenced device part. During researches carried out in a climatic chamber, discrepancy of the both flange temperature and mounted on it sensor temperature is detected. The need of measuring system thermal inertia compensation for the purpose of error decrease is proved. The algorithm for transient flange temperature determining by forward heat transfer problem solution is formed. The inverse procedure is carried out for the purpose of discrepancy minimizing between true object temperature and measured temperature. Computational experiments are carried out for calculating lidar enclosure flange temperature field under known external heat transfer conditions with the use of special computer program and experimental data. The experiment results enable to conclude about the value of error emerging because of temperature measuring system thermal inertia. We show application feasibility for proposed method of parametrical identification of differential-difference heat transfer model in object for error decrease during the device temperature monitoring and control.

  7. Monitoring brain temperature by time-resolved near-infrared spectroscopy: pilot study

    Science.gov (United States)

    Bakhsheshi, Mohammad Fazel; Diop, Mamadou; St. Lawrence, Keith; Lee, Ting-Yim

    2014-05-01

    Mild hypothermia (HT) is an effective neuroprotective strategy for a variety of acute brain injuries. However, the wide clinical adaptation of HT has been hampered by the lack of a reliable noninvasive method for measuring brain temperature, since core measurements have been shown to not always reflect brain temperature. The goal of this work was to develop a noninvasive optical technique for measuring brain temperature that exploits both the temperature dependency of water absorption and the high concentration of water in brain (80%-90%). Specifically, we demonstrate the potential of time-resolved near-infrared spectroscopy (TR-NIRS) to measure temperature in tissue-mimicking phantoms (in vitro) and deep brain tissue (in vivo) during heating and cooling, respectively. For deep brain tissue temperature monitoring, experiments were conducted on newborn piglets wherein hypothermia was induced by gradual whole body cooling. Brain temperature was concomitantly measured by TR-NIRS and a thermocouple probe implanted in the brain. Our proposed TR-NIRS method was able to measure the temperature of tissue-mimicking phantoms and brain tissues with a correlation of 0.82 and 0.66 to temperature measured with a thermometer, respectively. The mean difference between the TR-NIRS and thermometer measurements was 0.15°C±1.1°C for the in vitro experiments and 0.5°C±1.6°C for the in vivo measurements.

  8. Microchip transponder thermometry for monitoring core body temperature of antelope during capture.

    Science.gov (United States)

    Rey, Benjamin; Fuller, Andrea; Hetem, Robyn S; Lease, Hilary M; Mitchell, Duncan; Meyer, Leith C R

    2016-01-01

    Hyperthermia is described as the major cause of morbidity and mortality associated with capture, immobilization and restraint of wild animals. Therefore, accurately determining the core body temperature of wild animals during capture is crucial for monitoring hyperthermia and the efficacy of cooling procedures. We investigated if microchip thermometry can accurately reflect core body temperature changes during capture and cooling interventions in the springbok (Antidorcas marsupialis), a medium-sized antelope. Subcutaneous temperature measured with a temperature-sensitive microchip was a weak predictor of core body temperature measured by temperature-sensitive data loggers in the abdominal cavity (R(2)=0.32, bias >2 °C). Temperature-sensitive microchips in the gluteus muscle, however, provided an accurate estimate of core body temperature (R(2)=0.76, bias=0.012 °C). Microchips inserted into muscle therefore provide a convenient and accurate method to measure body temperature continuously in captured antelope, allowing detection of hyperthermia and the efficacy of cooling procedures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. On-Line Fuel Failure Monitor for Fuel Testing and Monitoring of Gas Cooled Very High Temperature Reactors

    International Nuclear Information System (INIS)

    Hawari, Ayman I.; Bourham, Mohamed A.

    2010-01-01

    Very High Temperature Reactors (VHTR) utilize the TRISO microsphere as the fundamental fuel unit in the core. The TRISO microsphere (∼ 1-mm diameter) is composed of a UO2 kernel surrounded by a porous pyrolytic graphite buffer, an inner pyrolytic graphite layer, a silicon carbide (SiC) coating, and an outer pyrolytic graphite layer. The U-235 enrichment of the fuel is expected to range from 4%-10% (higher enrichments are also being considered). The layer/coating system that surrounds the UO2 kernel acts as the containment and main barrier against the environmental release of radioactivity. To understand better the behavior of this fuel under in-core conditions (e.g., high temperature, intense fast neutron flux, etc.), the US Department of Energy (DOE) is launching a fuel testing program that will take place at the Advanced Test Reactor (ATR) located at Idaho National Laboratory (INL). During this project North Carolina State University (NCSU) researchers will collaborate with INL staff for establishing an optimized system for fuel monitoring for the ATR tests. In addition, it is expected that the developed system and methods will be of general use for fuel failure monitoring in gas cooled VHTRs.

  10. On0Line Fuel Failure Monitor for Fuel Testing and Monitoring of Gas Cooled Very High Temperature Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ayman I. Hawari; Mohamed A. Bourham

    2010-04-22

    IVery High Temperature Reactors (VHTR) utilize the TRISO microsphere as the fundamental fuel unit in the core. The TRISO microsphere (~ 1- mm diameter) is composed of a UO2 kernel surrounded by a porous pyrolytic graphite buffer, an inner pyrolytic graphite layer, a silicon carbide (SiC) coating, and an outer pyrolytic graphite layer. The U-235 enrichment of the fuel is expected to range from 4% – 10% (higher enrichments are also being considered). The layer/coating system that surrounds the UO2 kernel acts as the containment and main barrier against the environmental release of radioactivity. To understand better the behavior of this fuel under in-core conditions (e.g., high temperature, intense fast neutron flux, etc.), the US Department of Energy (DOE) is launching a fuel testing program that will take place at the Advanced Test Reactor (ATR) located at Idaho National Laboratory (INL). During this project North Carolina State University (NCSU) researchers will collaborate with INL staff for establishing an optimized system for fuel monitoring for the ATR tests. In addition, it is expected that the developed system and methods will be of general use for fuel failure monitoring in gas cooled VHTRs.

  11. Modeling of Temperature Field Evolution During Multilayered Direct Laser Metal Deposition

    Science.gov (United States)

    Zhang, DongYun; Feng, Zhe; Wang, ChengJie; Liu, Zhen; Dong, DongDong; Zhou, Yan; Wu, Rui

    2017-06-01

    It is of great importance to thoroughly explore the evolving temperature fields of direct laser metal deposition (abbreviated as LMD) in vertical thin wall manufacturing. It is helpful to control the temperature gradient, and even to adjust to forming microstructures and accumulation of residual stress. In this paper, a comprehensive three-dimensional transient model is developed for evolving temperature fields. The manufactured material is DS superalloy Rene80. The laser-powder interaction during the powder flowing process is simulated first, and its possible effect on the temperature field of the melting pool is analyzed. Then a 3D numerical simulation for the evolving temperature field is carried out based on considering transport phenomena during LMD such as the change in phase, powder injection and liquid flow. The applied deposition parameters are derived from experimental investigation with optimized vertical wall manufacturing. The simulated results explain why a balance between heat input and dissipation could form inside the vertical thin wall. These reconstruct the instability at an early phase of the building process without any temperature control unit and exhibit the influence of parameters such as laser power, deposition velocity and laser beam deposition pattern. The simulation results of temperature evolution are consistent with experimental investigation.

  12. Noise and DC balanced outlet temperature signals for monitoring coolant flow in LMFBR fuel elements

    International Nuclear Information System (INIS)

    Edelmann, M.

    1977-01-01

    Local cooling disturbances in LMFBR fuel elements may have serious safety implications for the whole reactor core. They have to be detected reliably in an early stage of their formation therefore. This can be accomplished in principle by individual monitoring of the coolant flow rate or the coolant outlet temperature of the sub-assemblies with high precision. In this paper a method is proposed to increase the sensitivity of outlet temperature signals to cooling disturbances. Using balanced temperature signals provides a means for eliminating the normal variations from the original signals which limit the sensitivity and speed of response to cooling disturbances. It is shown that a balanced signal can be derived easily from the original temperature signal by subtracting an inlet temperature and a neutron detector signal with appropriate time shift. The method was tested with tape-recorded noise signals of the KNK I reactor at Karlsruhe. The experimental results confirm the theoretical predictions. A significant reduction of the uncertainty of measured outlet temperatures was achieved. This enables very sensitive and fast response monitoring of coolant flow. Furthermore, it was found that minimizing the variance of the balanced signal offers the possibility for a rough determination of the heat transfer coefficient of the fuel rods during normal reactor operation at power. (author)

  13. Online monitoring of dynamic tip clearance of turbine blades in high temperature environments

    Science.gov (United States)

    Han, Yu; Zhong, Chong; Zhu, Xiaoliang; Zhe, Jiang

    2018-04-01

    Minimized tip clearance reduces the gas leakage over turbine blade tips and improves the thrust and efficiency of turbomachinery. An accurate tip clearance sensor, measuring the dynamic clearances between blade tips and the turbine case, is a critical component for tip clearance control. This paper presents a robust inductive tip clearance sensor capable of monitoring dynamic tip clearances of turbine machines in high-temperature environments and at high rotational speeds. The sensor can also self-sense the temperature at a blade tip in situ such that temperature effect on tip clearance measurement can be estimated and compensated. To evaluate the sensor’s performance, the sensor was tested for measuring the tip clearances of turbine blades under various working temperatures ranging from 700 K to 1300 K and at turbine rotational speeds ranging from 3000 to 10 000 rpm. The blade tip clearance was varied from 50 to 2000 µm. The experiment results proved that the sensor can accurately measure the blade tip clearances with a temporal resolution of 10 µm. The capability of accurately measuring the tip clearances at high temperatures (~1300 K) and high turbine rotation speeds (~30 000 rpm), along with its compact size, makes it promising for online monitoring and active control of blade tip clearances of high-temperature turbomachinery.

  14. Strontium titanate (100) surfaces monitoring by high temperature in situ ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Hrabovsky, D.; Berini, B. [Groupe d’Étude de la Matière Condensée (GEMaC), (UMR8635) Université de Versailles Saint-Quentin-en-Yvelines – CNRS, 45 Av. des États-Unis, 78035 Versailles (France); Fouchet, A., E-mail: fouchet@physique.uvsq.fr [Groupe d’Étude de la Matière Condensée (GEMaC), (UMR8635) Université de Versailles Saint-Quentin-en-Yvelines – CNRS, 45 Av. des États-Unis, 78035 Versailles (France); Aureau, D. [Institut Lavoisier de Versailles, (UMR 8180) Université de Versailles-Saint-Quentin-en-Yvelines – CNRS, 45 Av. des États-Unis, 78035 Versailles (France); Keller, N. [Groupe d’Étude de la Matière Condensée (GEMaC), (UMR8635) Université de Versailles Saint-Quentin-en-Yvelines – CNRS, 45 Av. des États-Unis, 78035 Versailles (France); Etcheberry, A. [Institut Lavoisier de Versailles, (UMR 8180) Université de Versailles-Saint-Quentin-en-Yvelines – CNRS, 45 Av. des États-Unis, 78035 Versailles (France); and others

    2016-03-30

    Graphical abstract: SrTiO{sub 3} surface contamination evidenced by in situ ellipsometry monitoring. Temperature dependence of overlayer thickness d of HF-treated SrTiO{sub 3} substrate: (1) The sample was heated up (full circles) then (2) cooled down (empty square). (3) The sample was out from the chamber on air for several weeks. (4) Heating up process was repeated. Irreversible behavior during heating up and cooling down indicate the desorption process leaving clean surface with only sub-nanometric roughness. Inset is AFM topographic images of atomic steps (500 nm × 500 nm) of as HF-treated substrate, with the 1 nm height scale. This demonstrates the necessity of in situ sensitive monitoring of the surface before thin film growth and surface analysis in particularly for low temperature deposition process. - Highlights: • In situ spectroscopic ellipsometry monitoring of the contamination layer with different atmosphere and temperature. • Evidence of desorption process of the contaminated layer until 550 °C for both random and TiO{sub 2} termination. • Confirmation of water and carbon contamination layer by XPS. - Abstract: We report monitoring and analysis of the contamination overlayer on the surface of different SrTiO{sub 3} (STO) substrates by in situ spectroscopic ellipsometry (SE) and ex situ X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Substrates of STO with different terminations, random and TiO{sub 2} terminated, were heated from room temperature up to 720 °C under oxygen pressure in UHV chamber similar to conditions commonly used for epitaxial growth of perovskite oxides. Contamination layer on the substrate was modeled as an equivalent dielectric overlayer with a thickness of 2 nm at room temperature which decreases progressively during the heating up to reach its minimum (around 1 unit cell) at the temperature around 550 °C. After exposition to air, surface recovers a contamination layer on both types of

  15. Structural study of high temperature metal-rich titanium sulfide phases

    Energy Technology Data Exchange (ETDEWEB)

    Owens, J.P.

    1979-01-01

    Ti/sub 2/S and Ti/sub 8/S/sub 3/ have been prepared by high temperature annealing techniques. The crystal structures of these two phases have been determined from single crystal x-ray diffraction data. Both structures were refined using a full-matrix least-squares treatment of positional parameters and isotropic temperature factor coefficients. Ti/sub 2/S crystallizes with orthorhombic symmetry, space group Pnnm, having unit cell dimensions a = 11.367A, b= 14.060A, and c = 3.326A. Ti/sub 2/S is isostructural with Ta/sub 2/P. Ti/sub 8/S/sub 3/ crystallizes with monoclinic symmetry, space group C2/m, a = 32.69A, b = 3.327A, c = 19.35A, ..beta.. = 139.9/sup 0/ (b - unique). Ti/sub 2/S and Ti/sub 8/S/sub 3/ have structural features similar to the features of a large number of metal-rich transition-metal chalcogenides and pnictides. These various structure types have been characterized in terms of nonmetal trigonal prismatic coordination polyhedra, eight different metal partial coordination polyhedra, a short (approximately equal to 3.4A) crystallographic axis, two unique layers of atoms containing both metal and nonmetal atom positions, and mirror planes coincident with the two layers of atom positions. The existence of a variety of structures with these structural features has led to their consideration as a unique structural class. The structural similarities and differences between the structure types of this class have been discussed in detail. Comparison of different structure types emphasized the importance of the metal bonding contribution in understanding the structural features and suggested limitations on qualitative bonding models used to understand the structural-chemical principles underlying structure stability.

  16. Direct writing of flexible electronics through room temperature liquid metal ink.

    Science.gov (United States)

    Gao, Yunxia; Li, Haiyan; Liu, Jing

    2012-01-01

    Conventional approaches of making a flexible circuit are generally complex, environment unfriendly, time and energy consuming, and thus expensive. Here, we describe for the first time the method of using high-performance GaIn(10)-based electrical ink, a significantly neglected room temperature liquid metal, as both electrical conductors and interconnects, for directly writing flexible electronics via a rather easy going and cost effective way. The new generation electric ink was made and its wettability with various materials was modified to be easily written on a group of either soft or rigid substrates such as epoxy resin board, glass, plastic, silica gel, paper, cotton, textiles, cloth and fiber etc. Conceptual experiments were performed to demonstrate and evaluate the capability of directly writing the electrical circuits via the invented metal ink. Mechanisms involved were interpreted through a series of fundamental measurements. The electrical resistivity of the fluid like GaIn(10)-based material was measured as 34.5 µΩ·cm at 297 K by four point probe method and increased with addition of the oxygen quantity, which indicates it as an excellent metal ink. The conductive line can be written with features that are approximately 10 µm thick. Several functional devices such as a light emitting diode (LED) array showing designed lighting patterns and electrical fan were made to work by directly writing the liquid metal on the specific flexible substrates. And satisfactory performances were obtained. The present method opens the way to directly and quickly writing flexible electronics which can be as simple as signing a name or drawing a picture on the paper. The unique merit of the GaIn(10)-based liquid metal ink lies in its low melting temperature, well controlled wettability, high electrical conductivity and good biocompability. The new electronics writing strategy and basic principle has generalized purpose and can be extended to more industrial areas, even

  17. Direct writing of flexible electronics through room temperature liquid metal ink.

    Directory of Open Access Journals (Sweden)

    Yunxia Gao

    Full Text Available BACKGROUND: Conventional approaches of making a flexible circuit are generally complex, environment unfriendly, time and energy consuming, and thus expensive. Here, we describe for the first time the method of using high-performance GaIn(10-based electrical ink, a significantly neglected room temperature liquid metal, as both electrical conductors and interconnects, for directly writing flexible electronics via a rather easy going and cost effective way. METHODS: The new generation electric ink was made and its wettability with various materials was modified to be easily written on a group of either soft or rigid substrates such as epoxy resin board, glass, plastic, silica gel, paper, cotton, textiles, cloth and fiber etc. Conceptual experiments were performed to demonstrate and evaluate the capability of directly writing the electrical circuits via the invented metal ink. Mechanisms involved were interpreted through a series of fundamental measurements. RESULTS: The electrical resistivity of the fluid like GaIn(10-based material was measured as 34.5 µΩ·cm at 297 K by four point probe method and increased with addition of the oxygen quantity, which indicates it as an excellent metal ink. The conductive line can be written with features that are approximately 10 µm thick. Several functional devices such as a light emitting diode (LED array showing designed lighting patterns and electrical fan were made to work by directly writing the liquid metal on the specific flexible substrates. And satisfactory performances were obtained. CONCLUSIONS: The present method opens the way to directly and quickly writing flexible electronics which can be as simple as signing a name or drawing a picture on the paper. The unique merit of the GaIn(10-based liquid metal ink lies in its low melting temperature, well controlled wettability, high electrical conductivity and good biocompability. The new electronics writing strategy and basic principle has generalized

  18. MATERIAL DEPENDENCE OF TEMPERATURE DISTRIBUTION IN MULTI-LAYER MULTI-METAL COOKWARE

    Directory of Open Access Journals (Sweden)

    MOHAMMADREZA SEDIGH

    2017-09-01

    Full Text Available Laminated structure is becoming more popular in cookware markets; however, there seems to be a lack of enough scientific studies to evaluate its pros and cons, and to show that how it functions. A numerical model using a finite element method with temperature-dependent material properties has been performed to investigate material and layer dependence of temperature distribution in multi-layer multi-metal plate exposed to irregular heating. Behavior of two parameters including mean temperature value and uniformity on the inner surface of plate under variations of thermal properties and geometrical conditions have been studied. The results indicate that conductive metals used as first layer in bi-layer plates have better thermal performance than those used in the second layer. In addition, since cookware manufacturers increasingly prefer to use all-clad aluminium plate, recently, this structure is analysed in the present study as well. The results show all-clad copper and aluminum plate possesses lower temperature gradient compared with single layer aluminum and all-clad aluminum core plates.

  19. The influence of temperature and salt on metal and sediment removal in stormwater biofilters.

    Science.gov (United States)

    Søberg, Laila C; Viklander, Maria; Blecken, Godecke-Tobias

    2014-01-01

    Stormwater biofilters are used to treat stormwater runoff. In countries with cold winter climates, biofilters are subject to low temperatures which, in some cases, are combined with potentially high salt concentrations from road de-icing, potentially affecting the biofilter's performance. Since stormwater biofilters have been developed without consideration of their critical winter use, a laboratory study was carried out to evaluate the performance of stormwater biofilters subjected to low and high temperatures, with and without salt. Both factors and their interaction had a significant effect on outflow concentrations and removal percentages. Salt had a negative impact on outflow concentrations, causing lower removal percentages for (especially dissolved) metals, this impact being most pronounced for Cu and Pb. The unrealistic combination of salt with high temperature seemed to further amplify the negative impacts of salt despite the fact that temperature alone did not cause significant differences in outflow concentrations and removal percentages. Still, biofilters showed the ability to treat stormwater efficiently under the simulated winter conditions; outflow concentrations for total metals as a minimum met the class 4 threshold value defined in the Swedish freshwater quality guidelines, while inflow concentrations clearly exceeded the threshold value for class 5. The relatively coarse filter material (which is recommended to facilitate infiltration during winter) did not seem to exacerbate biofilter performance.

  20. Potentiometric electronic tongue-flow injection analysis system for the monitoring of heavy metal biosorption processes.

    Science.gov (United States)

    Wilson, D; del Valle, M; Alegret, S; Valderrama, C; Florido, A

    2012-05-15

    An automated flow injection potentiometric (FIP) system with electronic tongue detection (ET) is used for the monitoring of biosorption processes of heavy metals on vegetable wastes. Grape stalk wastes are used as biosorbent to remove Cu(2+) ions in a fixed-bed column configuration. The ET is formed by a 5-sensor array with Cu(2+) and Ca(2+)-selective electrodes and electrodes with generic response to heavy-metals, plus an artificial neural network response model of the sensor's cross-response. The real-time monitoring of both the Cu(2+) and the cation exchanged and released (Ca(2+)) in the effluent solution is performed by using flow-injection potentiometric electronic tongue system. The coupling of the electronic tongue with automation features of the flow-injection system allows us to accurately characterize the Cu(2+) ion-biosorption process, through obtaining its breakthrough curves, and the profile of the Ca(2+) ion release. In parallel, fractions of the extract solution are analysed by spectroscopic techniques in order to validate the results obtained with the reported methodology. The sorption performance of grape stalks is also evaluated by means of well-established sorption models. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Conformable liquid metal printed epidermal electronics for smart physiological monitoring and simulation treatment

    Science.gov (United States)

    Wang, Xuelin; Zhang, Yuxin; Guo, Rui; Wang, Hongzhang; Yuan, Bo; Liu, Jing

    2018-03-01

    Conformable epidermal printed electronics enabled from gallium-based liquid metals (LMs), highly conductive and low-melting-point alloys, are proposed as the core to achieving immediate contact between skin surface and electrodes, which can avoid the skin deformation often caused by conventional rigid electrodes. When measuring signals, LMs can eliminate resonance problems with shorter time to reach steady state than Pt and gelled Pt electrodes. By comparing the contact resistance under different working conditions, it is demonstrated that both ex vivo and in vivo LM electrode-skin models have the virtues of direct and immediate contact with skin surface without the deformation encountered with conventional rigid electrodes. In addition, electrocardio electrodes composed of conformable LM printed epidermal electronics are adopted as smart devices to monitor electrocardiogram signals of rabbits. Furthermore, simulation treatment for smart defibrillation offers a feasible way to demonstrate the effect of liquid metal electrodes (LMEs) on the human body with less energy loss. The remarkable features of soft epidermal LMEs such as high conformability, good conductivity, better signal stability, and fine biocompatibility represent a critical step towards accurate medical monitoring and future smart treatments.

  2. High temperature liquid metal corrosion and high temperature electrical conductivity of Y{sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Yoneoka, Toshiaki; Terai, Takayuki [Tokyo Univ. (Japan). Faculty of Engineering; Takahashi, Yoichi

    1996-03-01

    Yttrium sesquioxide has been proposed as a promising candidate material for collector electrodes used in the laser enrichment system of uranium-235. For this purpose yttria is expected to be compatible with molten uranium and electrically conductive. The corrosion test of yttria with molten lanthanum as a simulating metal for uranium and the measurement of its electrical conductivity under extremely low oxygen pressure were performed. It was shown from the corrosion test that a yttria sample was considerably corroded by the molten lanthanum at 1513K, and the maximum corrosion depth for 5Ms was 0.162mm. The electrical conductivity of hypo-stoichiometric yttria above 300K reduced by titanium was higher than that of pure germanium at room temperature (2.1S/m). The oxygen pressures equilibrated with the yttria specimens were estimated to discuss the relation to measured conductivities. (author)

  3. High temperature liquid metal corrosion and high temperature electrical conductivity of Y{sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Yoneoka, T. [Tokyo Univ. (Japan). Dept. of Quantum Eng. and Syst. Sci.; Terai, T. [Engineering Research Institute, The University of Tokyo, Bunkyo-ku, Tokyo 113 (Japan); Takahashi, Y. [Department of Applied Chemistry, Chuo University, Bunkyo-ku, Tokyo 112 (Japan)

    1997-09-01

    Yttrium sesquioxide has been proposed as a promising candidate material for collector electrodes used in the laser enrichment system of uranium-235. For this purpose, yttria is expected to be compatible with molten uranium and electrically conductive. A corrosion test of yttria with molten lanthanum as a simulating metal for uranium and a measurement of its electrical conductivity under extremely low oxygen pressure were performed. It was shown from the corrosion test that a yttria sample was considerably corroded by the molten lanthanum at 1513 K and the maximum corrosion depth for 5 Ms was 0.162 mm. The electrical conductivity of hypo-stoichiometric yttria reduced by titanium was higher than that of pure germanium at room temperature (2.1 S/m). The oxygen pressures equilibrated with the yttria specimens were estimated to discuss the relation to measured conductivities. (orig.).

  4. Monitoring of heavy metals in wild mussels ( Mytilus galloprovincialis) from the Spanish North-Atlantic coast

    Science.gov (United States)

    Besada, Victoria; Manuel Andrade, José; Schultze, Fernando; José González, Juan

    2011-04-01

    Concentrations of five heavy metals (Hg, Cd, Pb, Cu and Zn) were determined in tissues of wild mussels ( Mytilus galloprovincialis) collected at 41 stations located on the Spanish Atlantic and Northern coasts to assess the levels and spatial distribution of metals in the environment. This study, performed in 2005, constituted a contribution to the last international OSPAR pollution monitoring survey. A pool of mussel soft tissue was prepared using 50 or more individuals, representing the size range present at the sampling points. Quantification was carried out after a nitric acid digestion by atomic absorption spectrometry, AAS (Cd and Pb by electrothermal AAS; Cu and Zn by flame AAS; and total mercury by the cold vapour technique). The quality of the chemical analyses was assessed by interlaboratory exercises carried out on a regular basis. In general, the levels of the metals were higher for the Northern region than for the Atlantic one (except for a sampling site close to Vigo, one of the main Galician industrial areas). Some Galician sampling points (Atlantic coast, NW of Spain) located far from human inputs showed high Cd concentrations, which were attributed to the annual upwelling processes in this region. The levels of Cu increased from Northwest to East, whereas Zn concentrations were very homogeneous throughout the two studied geographical regions. These results were confirmed using multivariate studies (PCA and cluster analysis), as well as international 'background assessment concentrations' criteria.

  5. An AES Study of the Room Temperature Surface Conditioning of Technological Metal Surfaces by Electron Irradiation

    OpenAIRE

    Scheuerlein, C; Hilleret, Noël; Taborelli, M; Brown, A; Baker, M A

    2002-01-01

    The modifications to technological copper and niobium surfaces induced by 2.5 keV electron irradiation have been investigated in the context of the conditioning process occurring in particle accelerator ultra high vacuum systems. Changes in the elemental surface composition have been found using Scanning Auger Microscopy (SAM) by monitoring the carbon, oxygen and metal Auger peak intensities as a function of electron irradiation in the dose range 10-6 to 10-2 C mm-2. The surface analysis resu...

  6. Specific-heat measurement of single metallic, carbon, and ceramic fibers at very high temperature

    International Nuclear Information System (INIS)

    Pradere, C.; Goyheneche, J.M.; Batsale, J.C.; Dilhaire, S.; Pailler, R.

    2005-01-01

    The main objective of this work is to present a method for measuring the specific heat of single metallic, carbon, and ceramic fibers at very high temperature. The difficulty of the measurement is due to the microscale of the fiber (≅10 μm) and the important range of temperature (700-2700 K). An experimental device, a modelization of the thermal behavior, and an analytic model have been developed. A discussion on the measurement accuracy yields a global uncertainty lower than 10%. The characterization of a tungsten filament with thermal properties identical to those of the bulk allows the validation of the device and the thermal estimation method. Finally, measurements on carbon and ceramic fibers have been done at very high temperature

  7. Temperature effects in contacts between a metal and a semiconductor nanowire near the degenerate doping

    Science.gov (United States)

    Sun, Zhuting; Burgess, Tim; Tan, H. H.; Jagadish, Chennupati; Kogan, Andrei

    2018-04-01

    We have investigated the nonlinear conductance in diffusion-doped Si:GaAs nanowires contacted by patterned metal films in a wide range of temperatures T. The wire resistance R W and the zero bias resistance R C, dominated by the contacts, exhibit very different responses to temperature changes. While R W shows almost no dependence on T, R C varies by several orders of magnitude as the devices are cooled from room temperature to T = 5 K. We develop a model that employs a sharp donor level very low in the GaAs conduction band and show that our observations are consistent with the model predictions. We then demonstrate that such measurements can be used to estimate carrier properties in nanostructured semiconductors and obtain an estimate for N D, the doping density in our samples. We also discuss the effects of surface states and dielectric confinement on carrier density in semiconductor nanowires.

  8. On the nature of low temperature internal friction peaks in metallic glasses

    International Nuclear Information System (INIS)

    Khonik, V.A.; Spivak, L.V.

    1996-01-01

    Low temperature (30 60 Nb 40 subjected to preliminary inhomogeneous deformation by cold rolling, homogeneous tensile deformation or electrolytic charging with hydrogen is investigated. Cold rolling or hydrogenation result in appearance of similar internal friction peaks and hysteresis damping. Homogeneous deformation has no influence on low temperature internal friction. The phenomenon of microplastic deformation during hydrogenation of weakly stressed samples is revealed. It is argued that microplastic deformation of metallic glasses during hydrogenation without external stress takes place too. Plastic flow both on cold rolling and hydrogenation occurs via formation and motion of dislocation-like defects which are the reason of the observed anelastic anomalies. It is concluded that low temperature internal friction peaks described in the literature for as-cast, cold deformed and hydrogenated samples have common dislocation-like origin

  9. Utilizing Rice Husk Briquettes in Firing Crucible Furnace for Low Temperature Melting Metals in Nigeria

    Directory of Open Access Journals (Sweden)

    N. A. Musa

    2012-08-01

    Full Text Available The search for alternative fuels for firing crucible furnace for low temperature melting metals has become mandatory, as a result of the pollution problem associated with the use of fossil fuels, the expense of electricity and also deforestation as a result of the use of charcoal. An agricultural waste, rice husk, in briquette form was used as an alternative fuel to fire crucible furnace to melt lead, zinc and aluminium. Results showed that lead and zinc melted and reached their pouring temperatures of 3840C and 5300C in 70 minutes and 75 minutes respectively. Aluminium was raised to a maximum temperature of 5200C in 75 and 100 minutes.The average concentration of the pollutants (CO, SO2and NOX were found to be below the tolerance limit and that of TSP (Total Suspended Particulates was found to be within the tolerance limit stipulated by Federal Environmental Protection Agency (FEPA in Nigeria.

  10. Locatable-body temperature monitoring based on semi-active UHF RFID tags.

    Science.gov (United States)

    Liu, Guangwei; Mao, Luhong; Chen, Liying; Xie, Sheng

    2014-03-26

    This paper presents the use of radio-frequency identification (RFID) technology for the real-time remote monitoring of body temperature, while an associated program can determine the location of the body carrying the respective sensor. The RFID chip's internal integrated temperature sensor is used for both the human-body temperature detection and as a measurement device, while using radio-frequency communication to broadcast the temperature information. The adopted RFID location technology makes use of reference tags together with a nearest neighbor localization algorithm and a multiple-antenna time-division multiplexing location system. A graphical user interface (GUI) was developed for collecting temperature and location data for the data fusion by using RFID protocols. With a puppy as test object, temperature detection and localization experiments were carried out. The measured results show that the applied method, when using a mercury thermometer for comparison in terms of measuring the temperature of the dog, has a good consistency, with an average temperature error of 0.283 °C. When using the associated program over the area of 12.25 m2, the average location error is of 0.461 m, which verifies the feasibility of the sensor-carrier location by using the proposed program.

  11. Locatable-Body Temperature Monitoring Based on Semi-Active UHF RFID Tags

    Directory of Open Access Journals (Sweden)

    Guangwei Liu

    2014-03-01

    Full Text Available This paper presents the use of radio-frequency identification (RFID technology for the real-time remote monitoring of body temperature, while an associated program can determine the location of the body carrying the respective sensor. The RFID chip’s internal integrated temperature sensor is used for both the human-body temperature detection and as a measurement device, while using radio-frequency communication to broadcast the temperature information. The adopted RFID location technology makes use of reference tags together with a nearest neighbor localization algorithm and a multiple-antenna time-division multiplexing location system. A graphical user interface (GUI was developed for collecting temperature and location data for the data fusion by using RFID protocols. With a puppy as test object, temperature detection and localization experiments were carried out. The measured results show that the applied method, when using a mercury thermometer for comparison in terms of measuring the temperature of the dog, has a good consistency, with an average temperature error of 0.283 °C. When using the associated program over the area of 12.25 m2, the average location error is of 0.461 m, which verifies the feasibility of the sensor-carrier location by using the proposed program.

  12. Temperature responsive hydrogel magnetic nanocomposites for hyperthermia and metal extraction applications

    International Nuclear Information System (INIS)

    Reddy, N. Narayana; Ravindra, S.; Reddy, N. Madhava; Rajinikanth, V.; Raju, K. Mohana; Vallabhapurapu, Vijaya Srinivasu

    2015-01-01

    The present work deals with the development of temperature and magnetic responsive hydrogel networks based on poly (N-isopropylacrylamide)/acrylamido propane sulfonic acid. The hydrogel matrices are synthesized by polymerizing N-isopropylacrylamide (NIPAM) monomer in the presence of acrylamido propane sulphonicacid (AMPS) using a cross-linker (N,N-methylenebisacrylamide, MBA) and redox initiating system [ammonium persulphate (APS)/tetramethylethylenediamine (TMEDA)]. The magnetic nanoparticles are generated throughout the hydrogel networks using in situ method by incorporating iron ions and subsequent treatment with ammonia. A series of hydrogel-magnetic nanocomposites (HGMNC) are developed by varying AMPS composition. The synthesized hydrogel magnetic nanocomposites (HGMNC) are characterized by using Fourier Transform Infrared (FTIR) Spectroscopy, X-ray diffraction (XRD), Thermal Analyses and Electron Microscopy analysis (Scanning and Transmission Electron Microscope). The metal extraction capacities of the prepared hydrogel (HG) and hydrogel magnetic nanocomposites (HGMNC) were studied at different temperatures. The results suggest that HGMNCs have higher extraction capacity compared to HG and HG loaded iron ions. This data also reveals that the extraction of metals by hydrogel magnetic nanocomposites (HGMNCs) is higher at higher temperatures than room temperature. The prepared HGMNCs are also subjected to hyperthermia (cancer therapy) studies. - Highlights: • We have developed temperature responsive hydrogel magnetic nanocomposites. • Addition of AMPS monomer to this magnetic hydrogel enhances the temperature sensitivity to 40–43 °C. • Similarly the sulfonic groups present in the AMPS units enhances the swelling ratio of magnetic hydrogels. • AMPS acts as good stabilizing agent for nanoparticles in the magnetic nanogel

  13. Dynamic temperature monitoring and control with fully distributed fiber Bragg grating sensor

    Science.gov (United States)

    Ding, Yuetong; Chen, Na; Chen, Zhenyi; Pang, Fufei; Zeng, Xianglong; Wang, Tingyun

    2010-11-01

    In this paper, fiber Bragg grating (FBG) is used as a fully distributed sensor to monitor tissue dynamic temperature changes during laser-induced interstitial thermotherapy (LITT). This work is mainly realized by the correlative single particle (CSP) algorithm, which is a rapid algorithm for spectrum reconstruction. Experimental LITT treatment was set up by using 532nm laser applicator on a piece of fresh liver tissue. In the experiments, the dynamic temperature profile was successfully demodulated with a refreshing speed of 11 seconds. With the aid of dynamic feedback, the thermotherapy boundary temperature was well controlled around 35°C during the treatment by adjusting the laser output power in real-time. Therefore, with this method, it is promising to precisely control the tissue temperature in vivo and improve the safety of the LITT remarkably.

  14. Saturation margin and core exit temperature monitoring system of Loviisa nuclear power plant

    International Nuclear Information System (INIS)

    Ekamn, I.

    1986-01-01

    One of the lessons learned from TMI accident is that the operators need better information in the control room on cooling conditions of the reactor core. For this reason it was decided that a new system for saturation margin and core exit temperature monitoring is implemented in Loviisa nuclear power plant. The system measures primary circuit pressure, hot leg temperature and core exit temperature. The measurement signals are led to a microprocessor based digital unit for calculations and signal conditioning. As outputs of the digital unit temperatures and saturation margin are displayed in various display modes in the control room console. The paper discusses the background of the chosen system concept and the tasks of the system. A system description is presented including the equipment techniques used. A discussion of accuracy questions and testing and commissioning is presented. (author)

  15. Catalysis of metal-clay intercalation compound in the low temperature coal hydrogasification

    Energy Technology Data Exchange (ETDEWEB)

    Fuda, Kiyoshi; Kimura, Mitsuhiko; Miyamoto, Norimitsu; Matsunaga, Toshiaki

    1986-10-23

    Focusing the hydrogenating methanation by gaseous phase catalytic reactions of low temperature volatile components, the catalytic effects of Ni metal and the effects of carriers having sensitive effects on the catalytic activities of Ni metal were studied. Sample coals were prepared from Shin-Yubari coal, and Ni hydride-montmorillonite complex catalysts and the catalysts produced by carring Ni nitrate on alumina and burning in hydrogen gas flows were prepared. The hydrogasification were carried out in a reaction tube. As a result, the montmorillonite-Ni compounds catalysts had high catalitic effects and high conversion ratio of 90% or more in the low temperature coal gasification. The catalitic effects of carried Ni metal strongly depended on the carrier substances, and the rank of effects for the carriers was montmorillonite>zeorite>TiO/sub 2/>alpha-Al/sub 2/O/sub 3/>MgO>SiO/sub 2/=gamma-Al/sub 2/O/sub 3/. (3 figs, 3 tabs, 3 refs)

  16. Microarray study of temperature-dependent sensitivity and selectivity of metal/oxide sensing interfaces

    Science.gov (United States)

    Tiffany, Jason; Cavicchi, Richard E.; Semancik, Stephen

    2001-02-01

    Conductometric gas microsensors offer the benefits of ppm-level sensitivity, real-time data, simple interfacing to electronics hardware, and low power consumption. The type of device we have been exploring consists of a sensor film deposited on a "microhotplate"- a 100 micron platform with built-in heating (to activate reactions on the sensing surface) and thermometry. We have been using combinatorial studies of 36-element arrays to characterize the relationship between sensor film composition, operating temperature, and response, as measured by the device's sensitivity and selectivity. Gases that have been tested on these arrays include methanol, ethanol, dichloromethane, propane, methane, acetone, benzene, hydrogen, and carbon monoxide, and are of interest in the management of environmental waste sites. These experiments compare tin oxide films modified by catalyst overlayers, and ultrathin metal seed layers. The seed layers are used as part of a chemical vapor deposition process that uses each array element's microheater to activate the deposition of SnO2, and control its microstructure. Low coverage (20 Ê) catalytic metals (Pd, Cu, Cr, In, Au) are deposited on the oxides by masked evaporation or sputtering. This presentation demonstrates the value of an array-based approach for developing film processing methods, measuring performance characteristics, and establishing reproducibility. It also illustrates how temperature-dependent response data for varied metal/oxide compositions can be used to tailor a microsensor array for a given application.

  17. Monitoring an Induced Permafrost Warming Experiment Using ERT, Temperature, and NMR in Fairbanks, Alaska

    Science.gov (United States)

    Ulrich, C.; Ajo Franklin, J. B.; Ekblaw, I.; Lindsey, N.; Wagner, A. M.; Saari, S.; Daley, T. M.; Freifeld, B. M.

    2016-12-01

    As global temperatures continue to rise, permafrost landscapes will experience more rapid changes than other global climate zones. Permafrost thaw is a result of increased temperatures in arctic settings resulting in surface deformation and subsurface hydrology changes. From an engineering perspective, surface deformation poses a threat to the stability of existing infrastructure such as roads, utility piping, and building structures. Preemptively detecting or monitoring subsurface thaw dynamics presents a difficult challenge due to the long time scales as deformation occurs. Increased subsurface moisture content results from permafrost thaw of which electrical resistivity tomography (ERT), soil temperature, and nuclear magnetic resonance (NMR) are directly sensitive. In this experiment we evaluate spatial and temporal changes in subsurface permafrost conditions (moisture content and temperature) at a experimental heating plot in Fairbanks, AK. This study focuses on monitoring thaw signatures using multiple collocated electrical resistivity (ERT), borehole temperature, and borehole nuclear magnetic resonance (NMR) measurements. Timelapse ERT (sensitive to changes in moisture content) was inverted using collocated temperature and NMR to constrain ERT inversions. Subsurface thermal state was monitored with timelapse thermistors, sensitive to soil ice content. NMR was collected in multiple boreholes and is sensitive to changes in moisture content and pore scale distribution. As permafrost thaws more hydrogen, in the form of water, is available resulting in a changing NMR response. NMR requires the availability of liquid water in order to induce spin of the hydrogen molecule, hence, if frozen water molecules will be undetectable. In this study, the permafrost is poised close to 0oC and is mainly silt with small pore dimensions; this combination makes NMR particularly useful due to the possibility of sub-zero thaw conditions within the soil column. Overall this

  18. Effect of temperature on the visualization by digital color mapping of latent fingerprint deposits on metal.

    Science.gov (United States)

    Peel, Alicia; Bond, John W

    2014-03-01

    Visualization of fingerprint deposits by digital color mapping of light reflected from the surface of heated brass, copper, aluminum, and tin has been investigated using Adobe® Photoshop®. Metals were heated to a range of temperatures (T) between 50°C and 500°C in 50°C intervals with enhancement being optimal when the metals are heated to 250°C, 350°C, 50°C, and 300°C, respectively, and the hue values adjusted to 247°, 245°, 5°, and 34°, respectively. Fingerprint visualization after color mapping was not degraded by subsequent washing of the metals and color mapping did not compromise the visibility of the fingerprint for all values of T. The optimum value of T for fingerprint visibility is significantly dependent of the standard reduction potential of the metal with Kendall’s Tau (τ) = 0.953 (p < 0.001). For brass, this correlation is obtained when considering the standard reduction potential of zinc rather than copper.

  19. Study of radiation portal monitor and its application to metal recycling industry; Estudio de un sistema de deteccion tipo portico para su aplicacion en la industria del metal

    Energy Technology Data Exchange (ETDEWEB)

    Pujol, L.; Lara-Calleja, S.; Suarez-Navarro, M. J.; Gonzalez-Gonzalez, J. A.

    2009-07-01

    The industry of the iron and the steel in one of the most important sectors in Spain for its economic development. the recycling of metallic materials as well as the import of metallic scrap is very significant. Several reports on accidental dispersion or smelting of radioactive sources in metal recycling industries confirm the possibility that radioactive material might be mixed with scrap. In consequence, this type of accident shows the necessity of a rigorous and specific radiation control of the sector. The control of these materials with radioactive content can be carried out with radiation portal monitors installed at the entrance of these industries. The detection of radioactive materials presents special features as the continuous background acquisition or the minimisation of the relatively large number of innocent/nuisance detections. In the present work, we study a radiation portal monitor, the FHT-1388-T Thermo-Eberline. This is one of the usual radiation portal systems installed at the entrance of the metal recycling industry. Se study the characteristics and parameters of this portal monitor to optimise its use. furthermore, we propose some rapid tests for radiation portal systems in metal recycling industry. (Author) 16 refs.

  20. Effect of the temperature and relative humidity in dosemeters used for personnel monitoring

    International Nuclear Information System (INIS)

    Antonio Filho, J.

    1982-12-01

    The systematics of the combined effect of temperature and humidity on photographic dosimeters of the type Agfa-Gevaert, Kodak type II, III and the thermoluminescent dosimeters LiF:Mg,Ti (TLD-100, Harshaw), D-CaSO 4 :Dy-0,4 (Teledyne), e CaSO 4 :Dy+NaCl (IPEN), used in personal monitoring in Brazil was investigated, in the temperature range of 20 0 C to 50 0 C and relative humidity of 65% to 95%, in order to determine the best manner of utilization of these detectors in Brazilian climatic conditions. The dosimeters were studied in different forms of packing-sheet such as aluminezed paper and polyethylene. For the determination of the systematics, the dosimeters were irradiated in three conditions: before, during and after of storage in climatic chambers to a maximum period of 60 days. It was found that the dosimetric filmes and thermoluminescent dosimeter CaSO 4 :Dy+NaCl without protection, presented a high dependence to temperature and humidity, and when protected presented good results. Therefore, the best manner of utilization of these monitors in environments with relative humidity and temperature greater them 75% and 30 0 C respectively, is achieved with the protection of aluminized paper. The LiF:Mg,Ti and D+CaSO 4 :Dy-0,4 dosimeters can be utilized in their original form because they presented low dependence with humidity and temperature in the range studied. (Author) [pt

  1. The effect of transition metals additions on the temperature coefficient of linear expansion of titanium and vanadium

    International Nuclear Information System (INIS)

    Lesnaya, M.I.; Volokitin, G.G.; Kashchuk, V.A.

    1976-01-01

    Results are reported of an experimental research into the influence of small additions of α-transition metals on the temperature coefficient of linear expansion of titanium and vanadium. Using the configuration model of substance as the basis, expeained are the lowering of the critical liquefaction temperature or the melting point of vanadium and the raising of it, as caused by the addition of metals of the 6 group of the periodic chart and by the addition of metals of the 8 group, respectively, and also a shift in the temperature of the polymorphic α-β-transformation of titanium. Suggested as the best alloying metal for vanadium are tungsten and tantalum; for titaniums is vanadium whose admixtures lower the melting point and shift the polymorphic transformation temperature by as much as 100 to 120 degrees

  2. Determination of Optimal Temperature for Biosorption of Heavy Metal Mixture from Aqueous Solution by Pretreated Biomass of Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Javad Yousefi

    2012-01-01

    Full Text Available Biosorption is a novel technology that uses dead and inactive biomass for removal of heavy metals from aqueous solution. Some parameters such as temperature, contact time, solution pH, initial metal concentration, biosorbent dose and also agitating speed of solution and biosorbent mixing can affect the amount of metal sorption by biosorbent. The aim of this study was to investigate the effects of different treatments of temperatures (25, 35, 45 and 55oC on biosorption of metals mixture in order to determine optimal temperature for more metals removal from aqueous solution. This study uses dead and pretreated biomass of Aspergillus niger with 0.5N NaOH for removal of Zn(II, Co(II and Cd(II. In all temperature treatments and in the case of all of heavy metals, maximum amount of metal sorption and concentration decrease was occurred in first 5 minutes and achieved to equilibrium after 20 minute. The percent of metals sorption show growth trend with temperature increase. Between 4 experimental treatments, 55oC treatment was shown maximum sorption and 25oC was shown minimum sorption amount. The percent of Cr(II sorption was increase from 28.5% in 25oC to 44.7% in 55oC. Also, this increase was from 40% to 58% for Cd(II and from 37.7% to 65.6% for Zn(II. About 60% of increase in sorption by A. niger was due to increase in temperature. Therefore the amount of metals sorption can be increase, only with temperature increase and without any biomass addition.

  3. A Data Transmission Algorithm Based on Dynamic Grid Division for Coal Goaf Temperature Monitoring

    Directory of Open Access Journals (Sweden)

    Qingsong Hu

    2014-01-01

    Full Text Available WSN (wireless sensor network is a perfect tool of temperature monitoring in coal goaf. Based on the three-zone theory of goaf, the GtmWSN model is proposed, and its dynamic features are analyzed. Accordingly, a data transmission scheme, named DTDGD, is worked out. Firstly, sink nodes conduct dynamic grid division on the GtmWSN according to virtual semicircle. Secondly, each node will confirm to which grid it belongs based on grid number. Finally, data will be delivered to sink nodes with greedy forward and hole avoidance. Simulation results and field data showed that the GtmWSN and DTDGD satisfied the lifetime need of goaf temperature monitoring.

  4. Influence of Cooling Rate in High-Temperature Area on Hardening of Deposited High-Cutting Chrome-Tungsten Metal

    International Nuclear Information System (INIS)

    Malushin, N N; Valuev, D V; Valueva, A V; Serikbol, A; Borovikov, I F

    2015-01-01

    The authors study the influence of cooling rate in high-temperature area for thermal cycle of high-cutting chrome-tungsten metal weld deposit on the processes of carbide phase merging and austenite grain growth for the purpose of providing high hardness of deposited metal (HRC 64-66). (paper)

  5. Combining Raman Microprobe and XPS to Study High Temperature Oxidation of Metals

    International Nuclear Information System (INIS)

    Windisch, Charles F.; Henager, Charles H.; Engelhard, Mark H.; Bennett, Wendy D.

    2011-01-01

    Raman microprobe spectroscopy was applied in studies of high-temperature air oxidation of a ferritic alloy (HT-9) in the absence and presence of zirconia coatings with the objective of evaluating the technique as a way to quickly screen candidate cladding materials and actinide-based mixed oxide fuel mixtures for advanced nuclear reactors. When oxidation was relatively uniform, Raman spectra collected using microscope optics with low spatial resolution were found to be similar to those collected with conventional Raman spectroscopy. These spectra could be used to identify major oxide corrosion products and follow changes in the composition of the oxides due to heating. However, when the oxidation films were comprised of multiple layers of varying composition, or with layers containing metallic phases, techniques with higher depth resolution and sensitivity to zero-valence metals were necessary. The requirements were met by combining Raman microprobe using different optical configurations and x-ray photoelectron spectroscopy.

  6. Behavior of Alkali Metals and Ash in a Low-Temperature Circulating Fluidized Bed (LTCFB) Gasifier

    DEFF Research Database (Denmark)

    Narayan, Vikas; Jensen, Peter Arendt; Henriksen, Ulrik Birk

    2016-01-01

    , the low reactor temperature ensures that high-alkali biomass fuels canbe used without risk of bed defluidization. This paper presents the first investigation of the fate of alkali metals and ash in lowtemperaturegasifiers. Measurements on bed material and product gas dust samples were made on a 100 k......W and a 6 MW LTCFBgasifier. Of the total fuel ash entering the system, the largest fraction (40−50%) was retained in the secondary cyclone bottoms,while a lower amount (8−10%) was released as dust in the exit gas. Most of the alkali and alkaline earth metals were retained inthe solid ash, along with Si...... by the particle size and the cut size ofthe primary and secondary cyclones. A model accounting for the ash collection by the plant cyclones was shown to predict theproduct gas ash particle release reasonably well....

  7. Fracture-resistant thin-film metallic glass: Ultra-high plasticity at room temperature

    Directory of Open Access Journals (Sweden)

    Chia-Chi Yu

    2016-11-01

    Full Text Available We report the first example of room-temperature rubber-like deformation in thin-film metallic glasses (TFMGs, 260-nm-thick Zr60Cu24Al11Ni5 layers, under ultra-high shear strain. The TFMGs were deposited, with no external heating, on Zr-based bulk metallic glass (BMG and Si(001 substrates by rf magnetron sputtering in a 3 mTorr Ar plasma. Cross-sectional transmission electron microscopy (XTEM analyses and nanoindentation results reveal that the TFMGs undergo an incredibly large shear strain, estimated to be ∼4000%, during fatigue tests, and thickness reductions of up to 61.5%, with no shear-banding or cracking, during extreme nanoindentation experiments extending through the film and into the substrate. TFMG/BMG samples also exhibit film/substrate diffusion bonding during deformation as shown by high-resolution XTEM.

  8. Tidal modulation of temperature oscillations monitored in borehole Yaxcopoil-1 (Yucatán, Mexico)

    Czech Academy of Sciences Publication Activity Database

    Čermák, Vladimír; Bodri, L.; Šafanda, Jan

    2009-01-01

    Roč. 282, č. 1-4 (2009), s. 131-139 ISSN 0012-821X R&D Projects: GA AV ČR(CZ) IAA300120603; GA ČR(CZ) GA205/06/1181 Institutional research plan: CEZ:AV0Z30120515 Keywords : temperature monitoring * borehole convection * tidal forcing * recurrence quantification interval * (RQI) analysis * histograms cumulation technique Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 4.062, year: 2009

  9. High resolution temperature monitoring in a borehole, detection of the deterministic signals in noisy environment

    Czech Academy of Sciences Publication Activity Database

    Čermák, Vladimír; Šafanda, Jan; Krešl, Milan

    2008-01-01

    Roč. 52, č. 3 (2008), s. 413-437 ISSN 0039-3169 R&D Projects: GA AV ČR(CZ) IAA300120603; GA ČR(CZ) GA205/06/1181 Institutional research plan: CEZ:AV0Z30120515 Keywords : borehole correction * recurrence analysis * temperature monitoring Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 0.770, year: 2008

  10. Temperature dataloggers as stove use monitors (SUMs): Field methods and signal analysis

    Science.gov (United States)

    Ruiz-Mercado, Ilse; Canuz, Eduardo; Smith, Kirk R.

    2013-01-01

    We report the field methodology of a 32-month monitoring study with temperature dataloggers as Stove Use Monitors (SUMs) to quantify usage of biomass cookstoves in 80 households of rural Guatemala. The SUMs were deployed in two stoves types: a well-operating chimney cookstove and the traditional open-cookfire. We recorded a total of 31,112 days from all chimney cookstoves, with a 10% data loss rate. To count meals and determine daily use of the stoves we implemented a peak selection algorithm based on the instantaneous derivatives and the statistical long-term behavior of the stove and ambient temperature signals. Positive peaks with onset and decay slopes exceeding predefined thresholds were identified as “fueling events”, the minimum unit of stove use. Adjacent fueling events detected within a fixed-time window were clustered in single “cooking events” or “meals”. The observed means of the population usage were: 89.4% days in use from all cookstoves and days monitored, 2.44 meals per day and 2.98 fueling events. We found that at this study site a single temperature threshold from the annual distribution of daily ambient temperatures was sufficient to differentiate days of use with 0.97 sensitivity and 0.95 specificity compared to the peak selection algorithm. With adequate placement, standardized data collection protocols and careful data management the SUMs can provide objective stove-use data with resolution, accuracy and level of detail not possible before. The SUMs enable unobtrusive monitoring of stove-use behavior and its systematic evaluation with stove performance parameters of air pollution, fuel consumption and climate-altering emissions. PMID:25225456

  11. Landau theory and giant room-temperature barocaloric effect in M F3 metal trifluorides

    Science.gov (United States)

    Corrales-Salazar, A.; Brierley, R. T.; Littlewood, P. B.; Guzmán-Verri, G. G.

    2017-10-01

    The structural phase transitions of M F3 (M = Al, Cr, V, Fe, Ti, Sc) metal trifluorides are studied within a simple Landau theory consisting of tilts of rigid M F6 octahedra associated with soft antiferrodistortive optic modes that are coupled to long-wavelength strain generating acoustic phonons. We calculate the temperature and pressure dependence of several quantities such as the spontaneous distortions, volume expansion, and shear strains as well as T -P phase diagrams. By contrasting our model to experiments we quantify the deviations from mean-field behavior and find that the tilt fluctuations of the M F6 octahedra increase with metal cation size. We apply our model to predict giant barocaloric effects in Sc-substituted TiF3 of up to about 15 JK -1kg-1 for modest hydrostatic compressions of 0.2 GPa . The effect extends over a wide temperature range of over 140 K (including room temperature) due to a large predicted rate, d Tc/d P =723 K GPa-1 , which exceeds those of typical barocaloric materials. Our results suggest that open lattice frameworks such as the trifluorides are an attractive platform to search for giant barocaloric effects.

  12. Development of program for evaluating the temperature of Zr-U metallic fuel rod

    International Nuclear Information System (INIS)

    Chun, J. S.; Lee, B. H.; Ku, Y. H.; Oh, J. Y.; Im, J. S.; Sohn, D. S.

    2003-01-01

    A code for evaluating the temperature of Zr-U metallic rod has been developed. Finite element (FE) method is adopted for the developed code sharing the user subroutines which has been prepared for the ABAQUS commercial FE code. The developed program for the Zr-U metallic fuel rod corresponds to a nonlinear transient heat transfer problem, and uses a sparse matrix solver for FE equations during iterations at every time step. The verifications of the developed program were conducted using the ABAQUS code. Steady state and transient problems were analyzed for 1/8 rod model due to the symmetry of the fuel rod and full model. From the evaluation of temperature for the 1/8 rod model at steady state, maximal error of 0.18 % was present relative to the ABAQUS result. Analysis for the transient problem using the fuel rod model resulted in the same as the variation of centerline temperature from the ABAQUS code during a hypothetical power transient. The distribution of heat flux for the entire cross section and surface was almost identical for the two codes

  13. High temperature oxidation of metals: vacancy injection and consequences on the mechanical properties

    International Nuclear Information System (INIS)

    Perusin, S.

    2004-11-01

    The aim of this work is to account for the effects of the high temperature oxidation of metals on their microstructure and their mechanical properties. 'Model' materials like pure nickel, pure iron and the Ni-20Cr alloy are studied. Nickel foils have been oxidised at 1000 C on one side only in laboratory air, the other side being protected from oxidation by a reducing atmosphere. After the oxidation treatment, the unoxidized face was carefully examined by using an Atomic Force Microscope (AFM). Grain boundaries grooves were characterised and their depth were compared to the ones obtained on the same sample heat treated in the reducing atmosphere during the same time. They are found to be much deeper in the case of the single side oxidised samples. It is shown that this additional grooving is directly linked to the growth of the oxide scale on the opposite side and that it can be explained by the diffusion of the vacancies produced at the oxide scale - metal interface, across the entire sample through grain boundaries. Moreover, the comparison between single side oxidised samples and samples oxidised on both sides points out that voids in grain boundaries are only observed in this latter case proving the vacancies condensation in the metal when the two faces are oxidised. The role of the carbon content and the sample's geometry on this phenomenon is examined in detail. The diffusion of vacancies is coupled with the transport of oxygen so that a mechanism of oxygen transport by vacancies is suggested. The tensile tests realised at room temperature on nickel foils (bamboo microstructure) show that the oxide scale can constitute a barrier to the emergence of dislocations at the metal surface. Finally, the Ni-20Cr alloy is tested in tensile and creep tests between 25 and 825 C in oxidising or reducing atmospheres. (author)

  14. Study of high-temperature plasticity of some group metal-base alloys on sign-variable deformation

    International Nuclear Information System (INIS)

    Smirnov, S.V.; Nesterenko, A.V.; Bykov, V.N.; Krinitsin, V.A.

    1993-01-01

    Temperature effect on 4 group metal alloy plasticity under sign-variable deformation is investigated. The deformation sign-variable character effect on plasticity is reduced with temperature growth. In contrast to monotonous deformation under which plasticity gross with temperature increase, a clearly manifested temperature range exists under sign-variable deformation where a shift deformation degree accumulated up to fracture is of the lightest importance

  15. Fiber optic sensing subsystem for temperature monitoring in space in-flight applications

    Science.gov (United States)

    Abad, S.; Araujo, F.; Pinto, F.; González Torres, J.; Rodriguez, R.; Moreno, M. A.

    2017-11-01

    Fiber Optic Sensor (FOS) technology presents long recognized advantages which enable to mitigate deficient performance of conventional technology in hazard-environments common in spacecraft monitoring applications, such as: multiplexing capability, immunity to EMI/RFI, remote monitoring, small size and weight, electrical insulation, intrinsically safe operation, high sensibility and long term reliability. A key advantage is also the potential reduction of Assembly Integration and Testing (AIT) time achieved by the multiplexing capability and associated reduced harness. In the frame of the ESA's ARTES5.2 and FLPP-Phase 3 programs, Airbus DS-Crisa and FiberSensing are developing a Fiber Bragg Grating (FBG) - based temperature monitoring system for application in space telecommunication platforms and launchers. The development encompasses both the interrogation unit and the FBG temperature sensors and associated fiber harness. In parallel Airbus DS - Crisa is developing a modular RTU (RTU2015) to provide maximum flexibility and mission-customization capability for RTUs maintaining the ESA's standards at I/O interface level [1]. In this context, the FBG interrogation unit is designed as a module to be compatible, in both physical dimensions and electrical interfaces aspects, with the Electrical Internal Interface Bus of the RTU2015, thus providing the capability for a hybrid electrical and optical monitoring system.

  16. INTELLIGENT MONITORING SYSTEM WITH HIGH TEMPERATURE DISTRIBUTED FIBEROPTIC SENSOR FOR POWER PLANT COMBUSTION PROCESSES

    Energy Technology Data Exchange (ETDEWEB)

    Kwang Y. Lee; Stuart S. Yin; Andre Boheman

    2003-12-26

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, the efforts focused on developing an innovative high temperature distributed fiber optic sensor by fabricating in-fiber gratings in single crystal sapphire fibers. So far, our major accomplishments include: Successfully grown alumina cladding layers on single crystal sapphire fibers, successfully fabricated in-fiber gratings in single crystal sapphire fibers, and successfully developed a high temperature distributed fiber optic sensor. Under Task 2, the emphasis has been on putting into place a computational capability for simulation of combustors. A PC workstation was acquired with dual Xeon processors and sufficient memory to support 3-D calculations. An existing license for Fluent software was expanded to include two PC processes, where the existing license was for a Unix workstation. Under Task 3, intelligent state estimation theory is being developed which will map the set of 1D (located judiciously within a 3D environment) measurement data into a 3D temperature profile. This theory presents a semigroup

  17. Continuous monitoring of Antarctic sub-ice shelf dynamics and ocean column temperatures

    Science.gov (United States)

    Kobs, S.; Tyler, S. W.; Zagorodnov, V.; Holland, D. M.; Stern, A.; Sledek, C.; Bryenton, J.

    2012-12-01

    Monitoring of ice shelf dynamics and sub-ice shelf ocean processes represents an important, but challenging step in understanding the dynamics of ice sheet behavior. In November 2011, a set of moorings through the McMurdo Ice Shelf at Windless Bight were installed to develop new installation and monitoring tools for understanding sub-ice shelf conditions. The mooring consists of fiber optic cables for distributed temperature sensing (DTS) extending from the surface, through 190m of ice shelf and to a depth of ~920m through the water column along with pressure transducer and independent thermistor strings. With DTS, temperature measurements are made every meter along the fiber optic cable. A continuous in time and depth temperature record was collected from late November 2011 through June 2012. A total of 5.5 million data points of temperature have been collected to date. The temperature record for the water column beneath the ice shelf clearly shows the intrusion of warm currents ( > -1.75 °C) under the ice shelf starting in late January and remaining present into May. Observed warming continues down through the water column into March, reaching depths of ~200m below the ice-ocean interface. The maximum recorded temperature occurred on March 7th and was -1.09 °C, indicating a maximum warming of ~0.8 °C. From March through May the water column began to cool back to the early spring isothermal condition of -1.9 °C. Temperature profiles within the shelf ice indicate a long-term basal melt rate of ~1 m/yr, preliminary observations from the ocean-ice interface show similar melt rates. The system is currently in a depowered state and will be revisited in the following field season.

  18. Spatial Soil Temperature and Moisture Monitoring Across the Transylvanian Plain, in Romania

    Science.gov (United States)

    Rusu, Teodor; Weindorf, David; Haggard, Beatrix; Moraru, Paula Ioana; Sopterean, Mara Lucia

    2011-01-01

    The Transylvanian Plain, Romania is an important region for agronomic productivity. However, limited soils data and adoption of best management practices hinder land productivity. Soil temperatures of the Transylvanian Plain were evaluated using a set of twenty datalogging stations positioned throughout the plain. Soil temperatures were monitored at the surface and at 10, 30, and 50 cm depths, and soil moisture was monitored at 10 cm. Preliminary results indicate that most soils of the Transylvanian Plain will have a mesic temperature regime. However, differences in seasonal warming and cooling trends across the plain were noted. These have important implications for planting recommendations. Growing degree days (GDDs) are preferred over maturity ratings, because they can account for temperature anomalies. The crop being considered for this study was corn. The base temperature (BT) was set at 10oC, and the upper threshold was 30oC. Two methods were used to calculate GDDs; 1) minimum and maximum daily temperatures, and 2) 24 h of averaged temperature data. Growing degree days were run from 110-199 day of year (DOY) to represent approximate planting date to tasseling. The DOY that 694 accumulated growing degree days (AGDDs) was reached at each site was then analyzed to identify differences across the TP. Three sites failed to reach 694 AGDDs by DOY 199, and were excluded from comparisons to other results. Averaged values were used to create spline interpolation maps with ArcMap 9.2 (ESRI, Redlands, CA, USA). The southeastern portion of the TP was found to tassel a month earlier assuming a planting date of 109 DOY. Four DeKalb® corn hybrids were then selected based on GDDs to tasseling, drydown, drought tolerance, and insect resistance. With a better understanding of the GDD trends across the TP, more effective planting and harvesting could be accomplished by Romanian farmers to maximize agronomic production.

  19. Monitoring the Electrolytic Reduction Process of Metal Oxide in the LiCl Molten Salt at 650 . deg. C

    International Nuclear Information System (INIS)

    Choi, In kyu; Hong, Soon Seok; Jung, Myoung Soo; Hur, Jin Mok; Lee, Han Soo

    2010-01-01

    During the electrolytic reduction process of metal oxides, metal oxides are reduced in the cathode basket and oxide ions are oxidized at a platinum anode. Basically the oxide concentration in the bulk should be maintained to be constant during the reduction process, but slow diffusion rate of oxide ions from metal oxide particles to the salt medium results in decreasing the oxide ion concentration. When a high current density is applied for the reduction, lowered lithium oxide concentration causes the platinum anode to be dissolved. To accomplish the reduction of metal oxides without serious damage of platinum anode, monitoring the lithium oxide concentration is very important. For in-situ monitoring the oxide concentration during the reduction, cyclic voltammetry (CV) and chronoamperometry(CA) were applied

  20. Effect of ion irradiation on tensile ductility, strength and fictive temperature in metallic glass nanowires

    International Nuclear Information System (INIS)

    Magagnosc, D.J.; Kumar, G.; Schroers, J.; Felfer, P.; Cairney, J.M.; Gianola, D.S.

    2014-01-01

    Ion irradiation of thermoplastically molded Pt 57.5 Cu 14.3 Ni 5.7 P 22.5 metallic glass nanowires is used to study the relationship between glass structure and tensile behavior across a wide range of structural states. Starting with the as-molded state of the glass, ion fluence and irradiated volume fraction are systematically varied to rejuvenate the glass, and the resulting plastic behavior of the metallic glass nanowires probed by in situ mechanical testing in a scanning electron microscope. Whereas the as-molded nanowires exhibit high strength, brittle-like fracture and negligible inelastic deformation, ion-irradiated nanowires show tensile ductility and quasi-homogeneous plastic deformation. Signatures of changes to the glass structure owing to ion irradiation as obtained from electron diffraction are subtle, despite relatively large yield strength reductions of hundreds of megapascals relative to the as-molded condition. To reconcile changes in mechanical behavior with glass properties, we adapt previous models equating the released strain energy during shear banding to a transit through the glass transition temperature by incorporating the excess enthalpy associated with distinct structural states. Our model suggests that ion irradiation increases the fictive temperature of our glass by tens of degrees – the equivalent of many orders of magnitude change in cooling rate. We further show our analytical description of yield strength to quantitatively describe literature results showing a correlation between severe plastic deformation and hardness in a single glass system. Our results highlight not only the capacity for room temperature ductile plastic flow in nanoscaled metallic glasses, but also processing strategies capable of glass rejuvenation outside of the realm of traditional thermal treatments

  1. Trends in low-temperature water–gas shift reactivity on transition metals

    DEFF Research Database (Denmark)

    Schumacher, Nana Maria Pii; Boisen, Astrid; Dahl, Søren

    2005-01-01

    Low-temperature water–gas shift reactivity trends on transition metals were investigated with the use of a microkinetic model based on a redox mechanism. It is established that the adsorption energies for carbon monoxide and oxygen can describe to a large extent changes in the remaining activation...... that the redox mechanism dominates and to the neglect of adsorbate interactions, which play an important role at high coverages. The model predicts that the activity of copper can be improved by increasing the strengths with which carbon monoxide and oxygen are bonded to the surface, thus suggesting possible...

  2. Elevated-Temperature Tensile-Testing of Foil-Gage Metals

    Science.gov (United States)

    Blackburn, L. B.; Ellingsworth, J. R.

    1986-01-01

    Automated system for measuring strain in metal foils at temperatures above 500 degrees F (260 degrees C) uses mechanical extensometer and displacement transducer. System includes counterbalance feature, which eliminates weight contribution of extensometer and reduces grip pressure required for attachment to specimen. Counterbalancing feature overcomes two major difficulties in using extensometers with foil-gage specimens: (1) Weight of extensometer and transducer represents significant fraction of total load applied to specimen and may actually damage it; and (2) grip pressure required for attachment of extensometer to specimens may induce bending stresses in foil-gage materials.

  3. Full integrated system of real-time monitoring based on distributed architecture for the high temperature engineering test reactor (HTTR)

    International Nuclear Information System (INIS)

    Subekti, Muhammad; Ohno, Tomio; Kudo, Kazuhiko; Takamatsu, Kuniyoshi; Nabeshima, Kunihiko

    2005-01-01

    A new monitoring system scheme based on distributed architecture for the High Temperature Engineering Test Reactor (HTTR) is proposed to assure consistency of the real-time process of expanded system. A distributed monitoring task on client PCs as an alternative architecture maximizes the throughput and capabilities of the system even if the monitoring tasks suffer a shortage of bandwidth. The prototype of the on-line monitoring system has been developed successfully and will be tested at the actual HTTR site. (author)

  4. Real time monitoring of water level and temperature in storage fuel pools through optical fibre sensors.

    Science.gov (United States)

    Rizzolo, S; Périsse, J; Boukenter, A; Ouerdane, Y; Marin, E; Macé, J-R; Cannas, M; Girard, S

    2017-08-18

    We present an innovative architecture of a Rayleigh-based optical fibre sensor for the monitoring of water level and temperature inside storage nuclear fuel pools. This sensor, able to withstand the harsh constraints encountered under accidental conditions such as those pointed-out during the Fukushima-Daiichi event (temperature up to 100 °C and radiation dose level up to ~20 kGy), exploits the Optical Frequency Domain Reflectometry technique to remotely monitor a radiation resistant silica-based optical fibre i.e. its sensing probe. We validate the efficiency and the robustness of water level measurements, which are extrapolated from the temperature profile along the fibre length, in a dedicated test bench allowing the simulation of the environmental operating and accidental conditions. The conceived prototype ensures an easy, practical and no invasive integration into existing nuclear facilities. The obtained results represent a significant breakthrough and comfort the ability of the developed system to overcome both operating and accidental constraints providing the distributed profiles of the water level (0-to-5 m) and temperature (20-to-100 °C) with a resolution that in accidental condition is better than 3 cm and of ~0.5 °C respectively. These new sensors will be able, as safeguards, to contribute and reinforce the safety in existing and future nuclear power plants.

  5. Sn-Mn binary metal oxides as non-carbon sorbent for mercury removal in a wide-temperature window.

    Science.gov (United States)

    Xie, Jiangkun; Xu, Haomiao; Qu, Zan; Huang, Wenjun; Chen, Wanmiao; Ma, Yongpeng; Zhao, Songjian; Liu, Ping; Yan, Naiqiang

    2014-08-15

    A series of Sn-Mn binary metal oxides were prepared through co-precipitation method. The sorbents were characterized by powder X-ray diffraction (powder XRD), transmission electronic microscopy (TEM), H2-temperature-programmed reduction (H2-TPR) and NH3-temperature-programmed desorption (NH3-TPD) methods. The capability of the prepared sorbents for mercury adsorption from simulated flue gas was investigated by fixed-bed experiments. Results showed that mercury adsorption on pure SnO2 particles was negligible in the test temperature range, comparatively, mercury capacity on MnOx at low temperature was relative high, but the capacity would decrease significantly when the temperature was elevated. Interestingly, for Sn-Mn binary metal oxide, mercury capacity increased not only at low temperature but also at high temperature. Furthermore, the impact of SO2 on mercury adsorption capability of Sn-Mn binary metal oxides was also investigated and it was noted that the effect at low temperature was different comparing with that of high temperature. The mechanism was investigated by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs). Moreover, a mathematic model was built to calculate mercury desorption activation energy from Sn to Mn binary metal oxides. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. High Temperature Monitoring the Height of Condensed Water in Steam Pipes

    Science.gov (United States)

    Bar-Cohen, Yoseph; Lih, Shyh-Shiuh; Badescu, Mircea; Bao, Xiaoqi; Sherrit, Stewart; Widholm, Scott; Ostlund, Patrick; Blosiu, Julian

    2011-01-01

    An in-service health monitoring system is needed for steam pipes to track through their wall the condensation of water. The system is required to measure the height of the condensed water inside the pipe while operating at temperatures that are as high as 250 deg. C. The system needs to be able to make real time measurements while accounting for the effects of cavitation and wavy water surface. For this purpose, ultrasonic wave in pulse-echo configuration was used and reflected signals were acquired and auto-correlated to remove noise from the data and determine the water height. Transmitting and receiving the waves is done by piezoelectric transducers having Curie temperature that is significantly higher than 250 deg. C. Measurements were made at temperatures as high as 250 deg. C and have shown the feasibility of the test method. This manuscript reports the results of this feasibility study.

  7. Identifying Time Periods of Minimal Thermal Gradient for Temperature-Driven Structural Health Monitoring.

    Science.gov (United States)

    Reilly, John; Glisic, Branko

    2018-03-01

    Temperature changes play a large role in the day to day structural behavior of structures, but a smaller direct role in most contemporary Structural Health Monitoring (SHM) analyses. Temperature-Driven SHM will consider temperature as the principal driving force in SHM, relating a measurable input temperature to measurable output generalized strain (strain, curvature, etc.) and generalized displacement (deflection, rotation, etc.) to create three-dimensional signatures descriptive of the structural behavior. Identifying time periods of minimal thermal gradient provides the foundation for the formulation of the temperature-deformation-displacement model. Thermal gradients in a structure can cause curvature in multiple directions, as well as non-linear strain and stress distributions within the cross-sections, which significantly complicates data analysis and interpretation, distorts the signatures, and may lead to unreliable conclusions regarding structural behavior and condition. These adverse effects can be minimized if the signatures are evaluated at times when thermal gradients in the structure are minimal. This paper proposes two classes of methods based on the following two metrics: (i) the range of raw temperatures on the structure, and (ii) the distribution of the local thermal gradients, for identifying time periods of minimal thermal gradient on a structure with the ability to vary the tolerance of acceptable thermal gradients. The methods are tested and validated with data collected from the Streicker Bridge on campus at Princeton University.

  8. Assessment of methane production from shredder waste in landfills: The influence of temperature, moisture and metals

    DEFF Research Database (Denmark)

    Fathi Aghdam, Ehsan; Scheutz, Charlotte; Kjeldsen, Peter

    2017-01-01

    different temperatures (20-25°C, 37°C, and 55°C), moisture contents (35% and 75% w/w) and amounts of inoculum (5% and 30% of the samples wet weight). The biochemical methane potential (BMP) from different types of SW (fresh, old and sieved) was determined and compared. The ability of metals (iron, aluminum.......235-0.488yr(-1) at 55°C, indicating that higher temperatures resulted in higher k-values. It was observed that H2 can be produced by biocorrosion of iron, aluminum, and zinc and it was shown that produced H2 can be utilized by hydrogenotrophic methanogens to convert CO2 to CH4. Addition of iron and copper...

  9. Strain measurement technique for elevated temperature tensile and creep testing of foil-gage metals

    Science.gov (United States)

    Blackburn, L. B.

    1988-01-01

    This paper describes a strain measurement technique suitable for elevated-temperature tensile and creep testing of foil-gage metals, using a modified commonly available mechanical extensometer in conjunction with a displacement transducer. The extensometer was modified by attaching to it a counterbalance (to reduce the effect of the extensometer weight on the total maximum test load) and by incorporating a conical tip/flat-edge design (to minimize induced stresses in the specimen resulting from extensometer attachment). Creep tests were performed on 0.102-mm-thick specimens of Ti-6Al-4V at temperatures of 427 and 538 C, at nominal applied stresses of 310.3 and 172.4 MPa, respectively. Examination of the resulting creep curves suggested that the strain measurement system provided actual creep strain values with good accuracy.

  10. Theory of Temperature Dependence of the Magnetization in Rare-Earth-Transition-Metal Alloys

    DEFF Research Database (Denmark)

    Szpunar, B.; Lindgård, Per-Anker

    1977-01-01

    It is shown that the temperature dependence of the magnetic moments and Curie and ferrimagnetic compensation temperatures for Gdl-xTx (T = Co, Ni, and Fe) and Y1-xCox can be accounted for by a simple model assuming a RKKY interaction between the rare-earth moments and the transition-metal pseudo-spin......1-xCox durch ein einfaches Model1 erklärt werden können, das eine RKKY-Wechsel-wirkung zwischen den Momenten der Seltenen Erden und des Pseudo-Spins des Übergangsmetalls annimmt. Die Wechselwirkung wird durch ein effektives Legierungsmedium übermittelt, das mit der CPA-Theorie und elliptischen...

  11. Monitoring of heavy metals in marine and freshwater fishes and nutritional evaluation of fish consumption

    International Nuclear Information System (INIS)

    Rina Mulyaningsih

    2014-01-01

    Fish is a food source of minerals. Uptake of heavy metals in fish could come from water, sediment and fish feed. Monitoring of minerals content and contaminants in fish has been carried out to evaluate nutrition and food safety, using neutron activation analysis techniques. Marine fish species that being analyzed are Kembung (Rastrelliger faughni), mackerel (Acanthocybium solandri), Tuna (Authis thazard) and freshwater fishes are Bawal (Colossoma macropomum), Nila (Oreochromis niloticus), Mas (Cyprinus carpio), sampled from 6 markets in North Jakarta. Monitoring results indicate that the essential minerals contained in fish are Fe, K, Na, Zn, Ca, Mg, and Se. Se and Ca concentrations in marine fish are higher than in freshwater fish. The concentration of other essential elements varies depending on the type of fish. The concentration of arsenic in marine fish is 3 times higher than that of freshwater fish; Hg and Cr content in all fish species were observed. From the evaluation of the adequacy of nutrition, with assuming a consumption of 86.68 g fish/day, for men aged 19 - 30 years, and referring to data from the Institute of Medicine USA, the Ca intake : 2.5 - 6.3; Cl : 1.5 - 3.3; Fe : 11.5 - 26.9; Na : 1.5 - 4.1; K : 3.4 - 6.7 and Zn 3.9 - 7.2% of the recommended value. Cr intake exceeds the recommended value, while As and Hg is not recommended in the food. In fact these metals contained in the studied fish, but the concentration is still below the value of standards issued by BPOM. (author)

  12. A Novel Ultraviolet Irradiation Technique for Fabrication of Polyacrylamide-metal (M = Au, Pd) Nanocomposites at Room Temperature

    International Nuclear Information System (INIS)

    Zhou, Y.; Hao, L.Y.; Zhu, Y.R.; Hu, Y.; Chen, Z.Y.

    2001-01-01

    Polyacrylamide (PAM)-metal (M = gold, palladium) nanocomposites with metal nanoparticles homogeneously dispersed in the polymer matrix have been prepared via a novel ultraviolet irradiation technique at room temperature, which is based on the simultaneous occurrence of photo-reduction formation of the colloidal metal particles and photo-polymerization of the acrylamide (AM) monomer. The UV-vis absorption spectra and TEM were employed to characterize the M-PAM nanocomposites by different irradiation times. The average sizes of the colloidal gold and palladium particles dispersed in the nanocomposites were calculated by XRD patterns and TEM images. The present method may be extended to prepare other metal-polymer hybrid nanocomposite materials

  13. Study of ultrasonic propagation through vortices for acoustic monitoring of high-temperature and turbulent fluid

    International Nuclear Information System (INIS)

    Massacret, Nicolas; Moysan, Joseph; Ploix, Marie-Aude; Chaouch, Naim; Jeannot, Jean-Philippe

    2016-01-01

    Ultrasonic monitoring in high temperature fluids with turbulences requires the knowledge of wave propagation in such media and the development of simulation tools. Applications could be the monitoring of sodium-cooled fast reactors. The objectives are mainly acoustic telemetry and thermometry, which involve the propagation of ultrasounds in turbulent and heated sodium flows. We developed a ray-tracing model to simulate the wave propagation and to determine wave deviations and delays due to an inhomogeneous medium. In previous work we demonstrated the sensitivity of ultrasounds to temperature gradients in liquid sodium. To complete that study, we need to investigate the sensitivity of ultrasounds to vortices created in a moving fluid. We designed a specific experimental setup called IKHAR (Instabilities of Kelvin-Helmholtz for Acoustic Research) in order to assess the validity of the ray-tracing model and the potential of ultrasounds for monitoring such fluid. In this experiment, Von Karman instabilities were created in a flow of water. Fluid temperature was homogeneous in our experimental setup. Through a careful choice of the parameters, periodic vortices were generated. The experiment was also simulated using Comsol registered to allow discussion about repeatability. The throughtransmission method was used to measure wave delays due to the vortices. Arrays of transducers were used to measure time of flight variations of several nanoseconds with a high spatial resolution. Results were similar to simulation results. They demonstrate that beam delays due to vortices can be measured and confirm the potential of ultrasounds in monitoring very inhomogeneous fluid media such as liquid sodium used as coolant fluid in nuclear fast reactors.

  14. Evaluation of a telemetric gastrointestinal pill for continuous monitoring of gastrointestinal temperature in horses at rest and during exercise

    NARCIS (Netherlands)

    Verdegaal, Elisabeth Lidwien J.M.M.; Delesalle, Catherine; Caraguel, Charles G.B.; Folwell, Louise E.; McWhorter, Todd J.; Howarth, Gordon S.; Franklin, Samantha H.

    2017-01-01

    OBJECTIVE To evaluate use of a telemetric gastrointestinal (GI) pill to continuously monitor GI temperature in horses at rest and during exercise and to compare time profiles of GI temperature and rectal temperature. ANIMALS 8 Standardbred horses. PROCEDURES Accuracy and precision of the GI pill and

  15. An evaluation of absorption spectroscopy to monitor YBa2Cu3O7-x precursors for metal organics chemical vapor deposition processing

    International Nuclear Information System (INIS)

    Matthew Edward Thomas

    1999-01-01

    Absorption spectroscopy was evaluated as a technique to monitor the metal organics chemical vapor deposition (MOCVD) process for forming YBa 2 Cu 3 O 7-x superconducting coated conductors. Specifically, this study analyzed the feasibility of using absorption spectroscopy to monitor the MOCVD supply vapor concentrations of the organic ligand 2,2,6,6-tetramethyl-3,5-heptanedionate (TMHD) metal chelates of barium, copper, and yttrium. Ba(TMHD) 2 , Cu(TMHD) 2 , and Y(TMHD) 3 compounds have successfully been vaporized in the MOCVD processing technique to form high temperature superconducting ''coated conductors,'' a promising technology for wire fabrication. The absorption study of the barium, copper, and yttrium (TMHD) precursors was conducted in the ultraviolet wavelength region from 200nm to 400nm. To simulate the MOCVD precursor flows the Ba(TMHD) 2 , Cu(TMHD) 2 , and Y(TMHD) 3 complexes were vaporized at vacuum pressures of (0.03--10)Torr. Spectral absorption scans of each precursor were conducted to examine potential measurement wavelengths for determining vapor concentrations of each precursor via Beer's law. The experimental results show that under vacuum conditions the barium, copper, and yttrium (TMHD) precursors begin to vaporize between 90 C and 135 C, which are considerably lower vaporization temperatures than atmospheric thermal gravimetric analyses indicate. Additionally, complete vaporization of the copper and yttrium (TMHD) precursors occurred during rapid heating at temperatures between 145 C and 195 C and after heating at constant temperatures between 90 C and 125 C for approximately one hour, whereas the Ba(TMHD) 2 precursor did not completely vaporize. At constant temperatures, near constant vaporization levels for each precursor were observed for extended periods of time. Detailed spectroscopic scans at stable vaporization conditions were conducted

  16. Micro-strip Metal Foil Detectors for the Beam Profile Monitoring

    CERN Document Server

    Pugatch, V M; Fedorovitch, O A; Mikhailenko, A V; Prystupa, S V; Pylypchenko, Y

    2005-01-01

    The Micro-strip Metal Foil Detectors (MMFD) designed and used for the Beam Profile Monitoring (BPM) are discussed. Fast particles hitting a metal strip initiate Secondary Electron Emission (SEE) which occurs at 10 - 50 nm surface layers of a strip. The SEE yield is measured by a sensitive Charge Integrator with built-in current-to-frequency converter (1 Hz per 1 fA). The MMFD (deposited onto the 20 μm thick Si-wafer) with 32 Al strips (10 μm wide, 32 μm pitch) has been used for the BPM of the 32 MeV alpha-particle beam at the MPIfK (Heidelberg) Tandem generator for Single-Event-Upset studies of the BEETLE micro-chip. Similar MMFD (0.5 μm thick Ni-strips) with totally removed Si-wafer (by plasma-chemistry, at the working area of 8 x 10 mm2) has been applied for the on-line X-ray BPM at the HASYLAB (DESY). The number of photons (11.3 GeV, mean X-ray energy 18 keV) producing out of a strip a single SEE was evaluated as (1.5 ±0.5)* 104. MMFD has demonstrated stable...

  17. Development of metallic system multi-composite materials for compound environment and corrosion monitoring technology

    International Nuclear Information System (INIS)

    Kiuchi, Kiyoshi

    1996-01-01

    For the structural materials used for the pressure boundary of nuclear power plants and others, the long term durability over several decades under the compound environment, in which the action of radiation and the corrosion and erosion in the environment of use are superposed, is demanded. To its controlling factors, the secular change of materials due to irradiation ageing and the chemical and physical properties of extreme compound environment are related complicatedly. In the first period of this research, the development of the corrosion-resistant alloys with the most excellent adaptability to environments was carried out by the combination of new alloy design and alloy manufacturing technology. In the second period, in order to heighten the adaptability as the pressure boundary materials between different compound environments, the creation of metallic system multi-composite materials has been advanced. Also corrosion monitoring technique is being developed. The stainless steel for water-cooled reactors, the wear and corrosion-resistant superalloy for reactor core, the corrosion-resistant alloy and the metallic refractory material for reprocessing nitric acid reaction vessels are reported. (K.I.)

  18. Platinum group metal particles aggregation in nuclear glass melts under the effect of temperature

    Energy Technology Data Exchange (ETDEWEB)

    Hanotin, Caroline [CEA Marcoule, DEN/MAR/DTCD/SECM/LDMC, Bagnols-sur-Cèze, F-30207 (France); Puig, Jean [Laboratoire PROMES-CNRS, UPR 8521, Font-Romeu Odeillo, F-66120 (France); Neyret, Muriel, E-mail: muriel.neyret@cea.fr [CEA Marcoule, DEN/MAR/DTCD/SECM/LDMC, Bagnols-sur-Cèze, F-30207 (France); Marchal, Philippe [Laboratoire Réactions et Génie des Procédés (LRGP-GEMICO), Université de Lorraine-CNRS, UMR 7274, Nancy F-54001 (France)

    2016-08-15

    The viscosity of simulated high level radioactive waste glasses containing platinum group metal particles is studied over a wide range of shear stress, as a function of the particles content and the temperature, thanks to a stress imposed rheometer, coupled to a high-temperature furnace. The system shows a very shear thinning behavior. At high shear rate, the system behaves as a suspension of small clusters and individual particles and is entirely controlled by the viscosity of the glass matrix as classical suspensions. At low shear rate, above a certain fraction in platinum group metal particles, the apparition of macroscopic aggregates made up of chains of RuO{sub 2} particles separated by thin layers of glass matrix strongly influences the viscosity of the nuclear glass and leads, in particular, to the apparition of yield stress and thixotropic effects. The maximum size of these clusters as well as their effective volume fraction have been estimated by a balance between Van der Waals attractive forces and hydrodynamic forces due to shear flow. We showed experimentally and theoretically that this aggregation phenomenon is favored by an increase of the temperature, owing to the viscosity decrease of the glass matrix, leading to an unusual increase of the suspension viscosity. - Highlights: • The macroscopic aggregates made up of RuO{sub 2} particles strongly influence the nuclear glass viscosity. • The maximum size of clusters as well as their effective volume fraction can be estimated. • This aggregation phenomenon is favored by an increase of the temperature. • A viscosity model as a function of the PGM content, volume fraction and shear stress is proposed.

  19. Low-temperature operation of copper-vapor lasers by using vapor-complex reaction of metallic copper and metal halide

    OpenAIRE

    SAITO, HIROSHI; TANIGUCHI, HIROSHI

    1985-01-01

    The first successful use of vapor-complex reactions for a laser is reported. Vapor-complex reactions between metallic copper and metal halides are found effective in reducing the operating temperature in copper-vapor lasers. By using a vapor-complex reaction of Cu+AlBr3, a laser oscillation starts at a reservoir temperature of about 25°C. The results obtained by the mass spectroscopic analysis support the presumption that the copper vapor is generated through a vapor-complex reaction process.

  20. Direct reduction of uranium dioxide and few other metal oxides to corresponding metals by high temperature molten salt electrolysis

    International Nuclear Information System (INIS)

    Mohandas, K.S.

    2017-01-01

    Molten salt based electro-reduction processes, capable of directly converting solid metal oxides to metals with minimum intermediate steps, are being studied worldwide. Production of metals apart, the process assumes importance in nuclear technology in the context of pyrochemical reprocessing of spent oxide fuels, for it serves as an intermediate step to convert spent oxide fuel to a metal alloy, which in turn can be processed by molten salt electro-refining method to gain the actinides present in it. In the context of future metal fuel fast reactor programme, the electrochemical process was studied for conversion of solid UO 2 to U metal in LiCl-1wt.% Li 2 O melt at 650 °C with platinum anode at the Metal Processing Studies Section, PMPD, IGCAR. A brief overview of the work is presented in the paper

  1. Nanoporous, Metal Carbide, Surface Diffusion Membranes for High Temperature Hydrogen Separations

    Energy Technology Data Exchange (ETDEWEB)

    Way, J. Douglas [Colorado School of Mines, Golden, CO (United States). Dept. of Chemical and Biological Engineering; Wolden, Colin A. [Colorado School of Mines, Golden, CO (United States)

    2013-09-30

    Colorado School of Mines (CSM) developed high temperature, hydrogen permeable membranes that contain no platinum group metals with the goal of separating hydrogen from gas mixtures representative of gasification of carbon feedstocks such as coal or biomass in order to meet DOE NETL 2015 hydrogen membrane performance targets. We employed a dual synthesis strategy centered on transition metal carbides. In the first approach, novel, high temperature, surface diffusion membranes based on nanoporous Mo2C were fabricated on ceramic supports. These were produced in a two step process that consisted of molybdenum oxide deposition followed by thermal carburization. Our best Mo2C surface diffusion membrane achieved a pure hydrogen flux of 367 SCFH/ft2 at a feed pressure of only 20 psig. The highest H2/N2 selectivity obtained with this approach was 4.9. A transport model using “dusty gas” theory was derived to describe the hydrogen transport in the Mo2C coated, surface diffusion membranes. The second class of membranes developed were dense metal foils of BCC metals such as vanadium coated with thin (< 60 nm) Mo2C catalyst layers. We have fabricated a Mo2C/V composite membrane that in pure gas testing delivered a H2 flux of 238 SCFH/ft2 at 600 °C and 100 psig, with no detectable He permeance. This exceeds the 2010 DOE Target flux. This flux is 2.8 times that of pure Pd at the same membrane thickness and test conditions and over 79% of the 2015 flux target. In mixed gas testing we achieved a permeate purity of ≥99.99%, satisfying the permeate purity milestone, but the hydrogen permeance was low, ~0.2 SCFH/ft2.psi. However, during testing of a Mo2C coated Pd alloy membrane with DOE 1 feed gas mixture a hydrogen permeance of >2 SCFH/ft2.psi was obtained which was stable during the entire test, meeting the permeance associated with

  2. High temperature corrosion of metallic interconnects in solid oxide fuel cells

    Directory of Open Access Journals (Sweden)

    Bastidas, D. M.

    2006-12-01

    Full Text Available Research and development has made it possible to use metallic interconnects in solid oxide fuel cells (SOFC instead of ceramic materials. The use of metallic interconnects was formerly hindered by the high operating temperature, which made the interconnect degrade too much and too fast to be an efficient alternative. When the operating temperature was lowered, the use of metallic interconnects proved to be favourable since they are easier and cheaper to produce than ceramic interconnects. However, metallic interconnects continue to be degraded despite the lowered temperature, and their corrosion products contribute to electrical degradation in the fuel cell. Coatings of nickel, chromium, aluminium, zinc, manganese, yttrium or lanthanum between the interconnect and the electrodes reduce this degradation during operation

    El uso de interconectores metálicos en pilas de combustible de óxido sólido (SOFC en sustitución de materiales cerámicos ha sido posible gracias a la investigación y desarrollo de nuevos materiales metálicos. Inicialmente, el uso de interconectores metálicos fue limitado, debido a la elevada temperatura de trabajo, ocasionando de forma rápida la degradación del material, lo que impedía que fuesen una alternativa. A medida que la temperatura de trabajo de las SOFC descendió, el uso de interconectores metálicos demostró ser una buena alternativa, dado que son más fáciles de fabricar y más baratos que los interconectores cerámicos. Sin embargo, los interconectores metálicos continúan degradándose a pesar de descender la temperatura a la que operan las SOFC y, asimismo, los productos de corrosión favorecen las pérdidas eléctricas de la pila de combustible. Recubrimientos de níquel, cromo, aluminio, zinc, manganeso, itrio y lantano entre el interconector y los electrodos reduce dichas pérdidas eléctricas.

  3. Low temperature synthesis of lamellar transition metal oxides containing surfactant ions

    Energy Technology Data Exchange (ETDEWEB)

    Janauer, G.G.; Chen, R.; Dobley, A.D.; Zavalij, P.Y.; Whittingham, M.S. [State Univ. of New York, Binghamton, NY (United States)

    1997-09-01

    Recently there has been much interest in reacting vanadium oxides hydrothermally with cationic surfactants to form novel layered compounds. A series of new transition metal oxides, however, has also been formed at or near room temperature in open containers. Synthesis, characterization, and proposed mechanisms of formation are the focus of this work. Low temperature reactions of vanadium pentoxide and ammonium (DTA) transition metal oxides with long chain amine surfactants, such as dodecyltrimethylammonium bromide yielded interesting new products many of which are layered phases. DTA{sub 4}H{sub 2}V{sub 10}O{sub 28}{center_dot}8H{sub 2}O, a layered highly crystalline phase, is the first such phase for which a single crystal X-ray structure has been determined. The unit cell for this material was found to be triclinic with space group P {bar 1} and dimensions a = 9.895(1){angstrom}, b = 11.596(1){angstrom}, c = 21.924(1){angstrom}, {alpha} = 95.153(2){degree}, {beta} = 93.778(1){degree}, and {gamma} = 101.360(1){degree}. Additionally, the authors synthesized a dichromate phase and a manganese chloride layered phase, with interlayer spacings of 26.8{angstrom}, and 28.7{angstrom} respectively. The structure, composition, and synthesis of the vanadium compound are described, as well as the synthesis and preliminary characterization of the new chromium and manganese materials.

  4. Thermal aging effects of VVER-1000 weld metal under operation temperature

    International Nuclear Information System (INIS)

    Chernobaeva, A.A.; Kuleshova, E.A.; Gurovich, B.A.; Erak, D.Y.; Zabusov, O.O.; Maltsev, D.A.; Zhurko, D.A.; Papina, V.B.; Skundin, M.A.

    2015-01-01

    The VVER-1000 thermal aging surveillance specimen sets are located in the reactor pressure vessel (RPV) under real operation conditions. Thermal aging surveillance specimens data are the most reliable source of the information about changing of VVER-1000 RPV materials properties because of long-term (hundred thousand hours) exposure at operation temperature. A revision of database of VVER-1000 weld metal thermal aging surveillance specimens has been done. The reassessment of transition temperature (T t ) for all tested groups of specimens has been performed. The duration of thermal exposure and phosphorus contents have been defined more precisely. The analysis of thermal aging effects has been done. The yield strength data, study of carbides evolution show absence of hardening effects due to thermal aging under 310-320 C degrees. Measurements of phosphorus content in grain boundaries segregation in different states have been performed. The correlation between intergranular fracture mode in Charpy specimens and transition temperature shift under thermal aging at temperature 310-320 C degrees has been revealed. All these data allow developing the model of thermal aging. (authors)

  5. Metallic magnetism at finite temperatures studied by relativistic disordered moment description: Theory and applications

    Science.gov (United States)

    Deák, A.; Simon, E.; Balogh, L.; Szunyogh, L.; dos Santos Dias, M.; Staunton, J. B.

    2014-06-01

    We develop a self-consistent relativistic disordered local moment (RDLM) scheme aimed at describing finite-temperature magnetism of itinerant metals from first principles. Our implementation in terms of the Korringa-Kohn-Rostoker multiple-scattering theory and the coherent potential approximation allows us to relate the orientational distribution of the spins to the electronic structure, thus a self-consistent treatment of the distribution is possible. We present applications for bulk bcc Fe, L10-FePt, and FeRh ordered in the CsCl structure. The calculations for Fe show significant variation of the local moments with temperature, whereas according to the mean-field treatment of the spin fluctuations the Curie temperature is overestimated. The magnetic anisotropy of FePt alloys is found to depend strongly on intermixing between nominally Fe and Pt layers, and it shows a power-law behavior as a function of magnetization for a broad range of chemical disorder. In the case of FeRh we construct a lattice constant vs temperature phase diagram and determine the phase line of metamagnetic transitions based on self-consistent RDLM free-energy curves.

  6. Development of a low-cost temperature data monitoring. An upgrade for hot box apparatus

    Science.gov (United States)

    de Rubeis, T.; Nardi, I.; Muttillo, M.

    2017-11-01

    The monitoring phase has gained a fundamental role in the energy efficiency evaluation of a system. Number and typology of the probes depend on the physical quantity to be monitored, and on the size and complexity of the system. Moreover, a measurement equipment should be designed to allow the employment of probes different for number and measured physical quantities. For this reason, a scalable equipment represents a good way for easily carrying out a system monitoring. Proprietary software and high costs characterize instruments of current use, thus limiting the possibilities to realize customized monitoring. In this paper, a temperature measuring instrument, conceived, designed, and realized for real time applications, is presented. The proposed system is based on digital thermometers and on open-source code. A remarkable feature of the instrument is the possibility of acquiring data from a high and variable number of probes (order of hundred), assuring flexibility of the software, since it can be programmed, and low-cost of the hardware components. The contemporary use of multiple temperature probes suggested to apply this instrument for a hot box apparatus, although the software can be set for recording different physical quantities. A hot box compliant with standard EN ISO 8990 should be equipped with several temperature probes to investigate heat exchanges of a specimen wall and thermal field of the chambers. In this work, preliminary tests have been carried out focusing only on the evaluation of the prototypal system’s performance. The tests were realized by comparing different sensors, such as thermocouples and resistance thermometers, traditionally employed in hot box experiments. A preliminary test was realized imposing a dynamic condition with a thermoelectric Peltier cell. Data obtained by digital thermometers DS18B20, compared with the ones of Pt100 probes, show a good correlation. Based on these encouraging results, a further test was carried out

  7. Real-time sensing and monitoring in robotic gas metal arc welding

    Science.gov (United States)

    Wu, C. S.; Gao, J. Q.; Hu, J. K.

    2007-01-01

    A real-time monitoring system is developed for detecting abnormal conditions in robotic gas metal arc welding. The butt-joint test pieces with simulated large gaps are used to intentionally introduce step disturbance of welding conditions. During the welding process, the welding voltage and current signals are sampled and processed on-line to extract the characteristic information reflecting the process quality. After the first statistical processing, it is found that seven statistical parameters (the mean, standard deviation, coefficient of variance and kurtosis of welding voltage; the mean, coefficient of variance and kurtosis of welding current) show variations during the step disturbance. Through the second statistical processing of the means of the welding voltage for subgroups of continuous measurement, the statistical control chart is obtained, and an SPC (statistical process control)-based on-line identifying method is developed. Ten robotic welding experiments are conducted to verify the real-time monitoring system. It is found that the correct identification rates for normal and abnormal welding conditions are 100% and 95%, respectively.

  8. Monitoring of metals, organic compounds and coliforms in water catchment points from the Sinos River basin.

    Science.gov (United States)

    Nascimento, C A; Staggemeier, R; Bianchi, E; Rodrigues, M T; Fabres, R; Soliman, M C; Bortoluzzi, M; Luz, R B; Heinzelmann, L S; Santos, E L; Fleck, J D; Spilki, F R

    2015-05-01

    Unplanned use and occupation of the land without respecting its capacity of assimilation and environmental purification leads to the degradation of the environment and of water used for human consumption. Agricultural areas, industrial plants and urban centres developed without planning and the control of effluent discharges are the main causes of water pollution in river basins that receive all the liquid effluents produced in those places. Over the last decades, environmental management has become part of governmental agendas in search of solutions for the preservation of water quality and the restoration of already degraded resources. This study evaluated the conditions of the main watercourse of the Sinos River basin by monitoring the main physical, chemical and microbiological parameters described in the CONAMA Resolution no. 357/2005.The set of parameters evaluated at five catchment points of water human consumption revealed a river that has different characteristics in each reach, as the upper reach was class 1, whereas the middle and lower reaches of the basin were class 4. Monitoring pointed to households as the main sources of pollutants in those reaches, although metals used in the industrial production of the region were found in the samples analyzed.

  9. Evaluation and monitoring of UVR in Shield Metal ARC Welding processing.

    Science.gov (United States)

    Peng, Chiung-yu; Liu, Hung-hsin; Chang, Cheng-ping; Shieh, Jeng-yueh; Lan, Cheng-hang

    2007-08-01

    This study established a comprehensive approach to monitoring UVR magnitude from Shield Metal Arc Welding (SMAW) processing and quantified the effective exposure based on measured data. The irradiances from welding UVR were calculated with biological effective parameter (Slambda) for human exposure assessment. The spectral weighting function for UVR measurement and evaluation followed the American Conference of Governmental Industrial Hygienists (ACGIH) guidelines. Arc welding processing scatters bright light with UVR emission over the full UV spectrum (UVA, UVB, and UVC). The worst case of effective irradiance from a 50 cm distance arc spot with a 200 A electric current and an electrode E6011 (4 mm) is 311.0 microW cm(-2) and has the maximum allowance time (Tmax) of 9.6 s. Distance is an important factor affecting the irradiance intensity. The worst case of the effective irradiance values from arc welding at 100, 200, and 300 cm distances are 76.2, 16.6, and 12.1 microW cm(-2) with Tmax of 39.4, 180.7, and 247.9 s, respectively. Protective materials (glove and mask) were demonstrated to protect workers from hazardous UVR exposure. From this study, the methodology of UVR monitoring in SMAW processing was developed and established. It is recommended that welders should be fitted with appropriate protective materials for protection from UVR emission hazards.

  10. Monitoring of (bio)available labile metal fraction in a drinking water treatment plant by diffusive gradients in thin films.

    Science.gov (United States)

    Díaz, Alfredo; Arnedo, Rebeca; Céspedes-Sánchez, Raquel; Devesa, Ricard; Martin-Alonso, Jordi

    2012-01-01

    A performance study of diffusive gradients in thin films (DGT) and inductively coupled plasma optical emission spectrometry (ICP-OES) was applied for the monitoring of the labile fraction of metals Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn, in Sant Joan Despí Drinking Water Treatment Plant located in the South of Barcelona's Metropolitan Area (Spain). The DWTP monitoring protocol was optimized by working for 1 day of deployment (24 h) with the DGT device in contact with both treated and river water matrixes. Additionally, it was demonstrated that an increase in the deployment time of 1 week did not decrease the evaluated concentrations of the studied metals. The quality parameters of the DGT device and ICP-OES determination, such as limit of quantification, accuracy expressed as relative error (%) and reproducibility expressed as relative standard deviation, were evaluated. Good results were obtained for all the metals in ultrapure water; limits of quantification ranged from 1.5 μg L( - 1) for cadmium to 28 μg L( - 1) for zinc when deployment time of 24 h was used and from 0.2 μg L( - 1) for cadmium to 4 μg L( - 1) for zinc when this time was increased by 1 week. Accuracy and precisions lower than or equal to 10% were obtained at a parametric concentration value of the metals regulated in the European Drinking Water Guidelines (98/83/EC). DGT deployment was tested in river and treated water, and good results were obtained for Cd, Ni, Co and Zn, whereas for the other metals, a continuous control of their metallic labile fractions was monitored. Therefore, DGT device allows the continuous monitoring of the labile metal species in a drinking water treatment plant.

  11. Large-volume and room-temperature gamma spectrometer for environmental radiation monitoring

    Directory of Open Access Journals (Sweden)

    Romain Coulon

    2017-10-01

    Full Text Available The use of a room-temperature gamma spectrometer is an issue in environmental radiation monitoring. To monitor radionuclides released around a nuclear power plant, suitable instruments giving fast and reliable information are required. High-pressure xenon (HPXe chambers have range of resolution and efficiency equivalent to those of other medium resolution detectors such as those using NaI(Tl, CdZnTe, and LaBr3:Ce. An HPXe chamber could be a cost-effective alternative, assuming temperature stability and reliability. The CEA LIST actively studied and developed HPXe-based technology applied for environmental monitoring. Xenon purification and conditioning was performed. The design of a 4-L HPXe detector was performed to minimize the detector capacitance and the required power supply. Simulations were done with the MCNPX2.7 particle transport code to estimate the intrinsic efficiency of the HPXe detector. A behavioral study dealing with ballistic deficits and electronic noise will be utilized to provide perspective for further analysis.

  12. Prediction of surface air temperatures by neural network, example based on three-year temperature monitoring at Spořilov station

    Czech Academy of Sciences Publication Activity Database

    Bodri, L.; Čermák, Vladimír

    2003-01-01

    Roč. 47, č. 1 (2003), s. 173-184 ISSN 0039-3169 R&D Projects: GA AV ČR IAA3012005 Institutional research plan: CEZ:AV0Z3012916 Keywords : surface air temperatures * neural network s * temperature monitoring Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.426, year: 2003

  13. High Temperature Stability of Dissimilar Metal Joints in Fission Surface Power Systems

    Science.gov (United States)

    Locci, Ivan E.; Nesbitt, James A.; Ritzert, Frank J.; Bowman, Cheryl L.

    2007-01-01

    Future generations of power systems for spacecraft and lunar surface systems will likely require a strong dependence on nuclear power. The design of a space nuclear power plant involves integrating together major subsystems with varying materia1 requirements. Refractory alloys are repeatedly considered for major structural components in space power reactor designs because refractory alloys retain their strength at higher temperatures than other classes of metals. The relatively higher mass and lower ductility of the refractory alloys make them less attractive for lower temperature subsystems in the power plant such as the power conversion system. The power conversion system would consist more likely of intermediate temperature Ni-based superalloys. One of many unanswered questions about the use of refractory alloys in a space power plant is how to transition from the use of the structural refractory alloy to more traditional structural alloys. Because deleterious phases can form when complex alloys are joined and operated at elevated temperatures, dissimilar material diffusion analyses of refractory alloys and superalloys are needed to inform designers about options of joint temperature and operational lifetime. Combinations of four superalloys and six refractory alloys were bonded and annealed at 1150 K and 1300 K to examine diffusional interactions in this study. Joints formed through hot pressing and hot isostatic pressing were compared. Results on newer alloys compared favorably to historical data. Diffusional stability is promising for some combinations of Mo-Re alloys and superalloys at 1150 K, but it appears that lower joint temperatures would be required for other refractory alloy couples.

  14. Can heavy metal pollution defend seed germination against heat stress? Effect of heavy metals (Cu(2+), Cd(2+) and Hg(2+)) on maize seed germination under high temperature.

    Science.gov (United States)

    Deng, Benliang; Yang, Kejun; Zhang, Yifei; Li, Zuotong

    2016-09-01

    Heavy metal pollution, as well as greenhouse effect, has become a serious threat today. Both heavy metal and heat stresses can arrest seed germination. What response can be expected for seed germination under both stress conditions? Here, the effects of heavy metals (Cu(2+), Cd(2+) and Hg(2+)) on maize seed germination were investigated at 20 °C and 40 °C. Compared with 20 °C, heat stress induced thermodormancy. However, this thermodormancy could be significantly alleviated by the addition of a low concentration of heavy metals. Heavy metals, as well as heat stress induced H2O2 accumulation in germinating seeds. Interestingly, this low concentration of heavy metal that promoted seed germination could be partly blocked by DMTU (a specific ROS scavenger), irrespective of temperature. Accordingly, H2O2 addition reinforced this promoting effect on seed germination, which was induced by a low concentration of heavy metal. Furthermore, we found that the NADPH oxidase derived ROS was required for seed germination promoted by the heavy metals. Subsequently, treatment of seeds with fluridone (a specific inhibitor of ABA) or ABA significantly alleviated or aggravated thermodormancy, respectively. However, this alleviation or aggravation could be partly attenuated by a low concentration of heavy metals. In addition, germination that was inhibited by high concentrations of heavy metals was also partly reversed by fluridone. The obtained results support the idea that heavy metal-mediated ROS and hormone interaction can finally affect the thermodormancy release or not. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Influence of temperature on strain monitoring of degradation in concrete containment buildings

    International Nuclear Information System (INIS)

    Ding, Y.; Jaffer, S.; Angell, P.

    2015-01-01

    Concrete containment buildings (CCBs) are important safety structures in a nuclear power plant (NPP). The CCBs can be made of reinforced and post-tensioned (P-T) concrete. Post-tensioning concrete induces compressive stresses, which have to be overcome for the concrete to crack under tensile loads. However, post-tensioned CCBs may undergo pre-stressing losses as they age, which could affect their performance under accident conditions. CANDU 6 reactor buildings contain grouted post-tensioned tendons as the primary reinforcement. The grouting of the tendons makes direct monitoring of pre-stressing losses via lift-off testing impossible. Therefore, instruments have been installed on an existing reactor building to measure and monitor strains and stresses in the concrete and the deformation of the concrete structure to detect aging degradation and indirectly evaluate the pre-stressing losses. However, the instrumentation readings are affected by temporary volume changes in the concrete caused by the influence of environmental factors, particularly temperature, on concrete. In this work, the focus is on developing an understanding of the effect of temperature on the interpretation of instrumentation data from a reactor building. Vibrating Wire Strain Gauge (VWSG) data has been analysed. The influence of concrete coefficient of thermal expansion and temperature distribution within the reactor building walls, on VWSG data, is discussed based on the analysis of the available instrumentation data and available numerical simulation results. The present study demonstrates that temperature distribution within the containment concrete has a significant impact on the VWSG measurements and the coefficient of thermal expansion of concrete is an important factor in the correction of VWSG data for thermal strain. It is recommended that VWSG data obtained over small temperature variations be considered for interpretation to assess pre-stressing losses. (authors)

  16. In and ex-vivo Myocardial Tissue Temperature Monitoring by Combined Infrared and Ultrasonic Thermometries

    Science.gov (United States)

    Engrand, C.; Laux, D.; Ferrandis, J.-Y.; Sinquet, J.-C.; Demaria, R.; Le Clézio, E.

    The success of cardiac surgery essentially depends on tissue preservation during intervention. Consequently a hypothermic cardio-plegia is applied in order to avoid ischemia. However, myocardial temperature is not monitored during operation. The aim of this study is then to find a relevant and simple method for myocardial global temperature estimation in real time using both ultrasounds and infra-red thermography. In order to quantify the sensitivity of ultrasonic velocity to temperature, a 2.25 MHz ultrasonic probe was used for ex-vivo tests. Pig myocards (n=25) were placed in a thermostatically-controlled water bath and measurements of the ultrasound velocity were realized from 10 to 30 ˚C. The results of this study indicate that the specificity and sensitivity of the ultrasonic echo delay induced by the modification of temperature can be exploited for in-depth thermometry. In parallel, for TIR experiments, a bolometer was used to detect the myocardium surface thermal evolution during in-vivo pig heart experiments. Hypothermic cardioplegic solutions were injected and infra-red surface imaging was performed during one hour. In the near futur, the correlation of the ultrasound and the infrared measurements should allow the real time estimation of the global temperature of the heart. The final objective being to realize in vivo measurements on human hearts, this information may have a very high importance in terms of per-operation inspection as well as decision making process during medical interventions.

  17. Temperature effects on the bridge structure during the all-day monitoring

    Directory of Open Access Journals (Sweden)

    Ondřej Michal

    2015-06-01

    Full Text Available In current time the large amount of pre-stressed bridge structures is used. Their horizontal and vertical displacements are well predicted, but for verification of theoretical results is necessary to measure real displacements of these structures depending on external conditions. Given by the complexity of the design and by the inhomogeneity of external influences (especially temperature of the atmosphere, insolation, wind speed, etc. cannot yet be reliably determined the changes of the construction caused by the immediate state of the environment and to distinguish them from irreversible (permanent deformation of the structure.In this paper the deflection line of the bridge of general Chábera over river Labe during the all-day monitoring will be analyzed. There is dense coverage of stabilized points enabling accurate approximation of the displacement of the bridge structure. The paper is focused especially on temperature effects on the bridge structure. The temperature changes cause the deformation of the construction not immediately, but with the time shift between change of temperature and structure deformation. Although the points are stabilized on both sides of the bridge deck, for the analysis of results were used only the points on the left side of the main span, where the biggest vertical displacements was detected. For testing of dependence of the time shift between the structure deformations and the structure temperature the Pearson coefficient of correlation was used.

  18. Identifying Time Periods of Minimal Thermal Gradient for Temperature-Driven Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    John Reilly

    2018-03-01

    Full Text Available Temperature changes play a large role in the day to day structural behavior of structures, but a smaller direct role in most contemporary Structural Health Monitoring (SHM analyses. Temperature-Driven SHM will consider temperature as the principal driving force in SHM, relating a measurable input temperature to measurable output generalized strain (strain, curvature, etc. and generalized displacement (deflection, rotation, etc. to create three-dimensional signatures descriptive of the structural behavior. Identifying time periods of minimal thermal gradient provides the foundation for the formulation of the temperature–deformation–displacement model. Thermal gradients in a structure can cause curvature in multiple directions, as well as non-linear strain and stress distributions within the cross-sections, which significantly complicates data analysis and interpretation, distorts the signatures, and may lead to unreliable conclusions regarding structural behavior and condition. These adverse effects can be minimized if the signatures are evaluated at times when thermal gradients in the structure are minimal. This paper proposes two classes of methods based on the following two metrics: (i the range of raw temperatures on the structure, and (ii the distribution of the local thermal gradients, for identifying time periods of minimal thermal gradient on a structure with the ability to vary the tolerance of acceptable thermal gradients. The methods are tested and validated with data collected from the Streicker Bridge on campus at Princeton University.

  19. Development of GUI Temperature Monitoring System based on Thin-Film Optical Filter

    Directory of Open Access Journals (Sweden)

    Hilal Adnan Fadhil

    2017-08-01

    Full Text Available Fiber optic sensors have progressed rapidly in recent year as because it has many advantages over other types of sensors in terms of freedom from electromagnetic radiation, wide bandwidth, economy, can withstand high temperature and under harsh environment. Due to those reason a thermo sensor based on fiber optic which utilizes a thin-film optical band-pass filter has been developed. However, the proposed system has advantages over the fiber Bragg grating sensor which can observe the temperature in small area and low transmission loss. The simulation software is used to design a Graphical User Interface (GUI. The GUI system allows the user to monitor the condition and the status of the current temperature. The monitoring system presented in this paper is divided into three basic sub-systems which are retrieve the real-time data system, displaying out the data system, and warning system. This GUI system used to collect the data and process the data for displaying the current data and further checking as a history data has been keep. The values obtained of thermo sensor are measured as 30°C till 330°C and the wavelength values are between 1552.93nm till 1557.25nm

  20. Impact of process temperature on GaSb metal-oxide-semiconductor interface properties fabricated by ex-situ process

    Science.gov (United States)

    Yokoyama, Masafumi; Asakura, Yuji; Yokoyama, Haruki; Takenaka, Mitsuru; Takagi, Shinichi

    2014-06-01

    We have studied the impact of process temperature on interface properties of GaSb metal-oxide-semiconductor (MOS) structures fabricated by an ex-situ atomic-layer-deposition (ALD) process. We have found that the ALD temperature strongly affects the Al2O3/GaSb MOS interface properties. The Al2O3/GaSb MOS interfaces fabricated at the low ALD temperature of 150 °C have the minimum interface-trap density (Dit) of ˜4.5 × 1013 cm-2 eV-1. We have also found that the post-metalization annealing at temperature higher than 200 °C degrades the Al2O3/GaSb MOS interface properties. The low-temperature process is preferable in fabricating GaSb MOS interfaces in the ex-situ ALD process to avoid the high-temperature-induced degradations.

  1. An AES Study of the Room Temperature Surface Conditioning of Technological Metal Surfaces by Electron Irradiation

    CERN Document Server

    Scheuerlein, C; Taborelli, M; Brown, A; Baker, M A

    2002-01-01

    The modifications to technological copper and niobium surfaces induced by 2.5 keV electron irradiation have been investigated in the context of the conditioning process occurring in particle accelerator ultra high vacuum systems. Changes in the elemental surface composition have been found using Scanning Auger Microscopy (SAM) by monitoring the carbon, oxygen and metal Auger peak intensities as a function of electron irradiation in the dose range 10-6 to 10-2 C mm-2. The surface analysis results are compared with electron dose dependent secondary electron and electron stimulated desorption yield measurements. Initially the electron irradiation causes a surface cleaning through electron stimulated desorption, in particular of hydrogen. During this period both the electron stimulated desorption and secondary electron yield decrease as a function of electron dose. When the electron dose exceeds 10-4 C mm-2 electron stimulated desorption yields are reduced by several orders of magnitude and the electron beam indu...

  2. Analysis of post-tensioned girders structural behaviour using continuous temperature and strain monitoring

    Science.gov (United States)

    Bednarski, Ł.; Sieńko, R.; Howiacki, T.

    2017-10-01

    This article presents the possibility of using structural health monitoring system data for the analysis of structure’s operation during its life cycle. Within the specific case study it was proved, that continuous, automatic and long term monitoring of selected physical quantities such as strains and temperatures, can significantly improve the assessment of technical condition by identifying hazardous phenomena. In this work the analysis of structural behaviour of post-tensioned girders within the roofing of sport halls in Cracow, Poland, was performed based on measurement results and verified by numerical model carried out in SOFiSTiK software. Thanks to the possibility of performing calculations in real time and informing the manager of the object about abnormalities it is possible to manage the structure in effective way by, inter alia, planning the renovations or supporting decisions about snow removal.

  3. Exploration of ion temperature profile measurements at JET using the upgraded neutron profile monitor

    International Nuclear Information System (INIS)

    Marocco, D.; Esposito, B.; Riva, M.

    2012-01-01

    The neutron profile monitor (NPM), routinely used at the Joint European Torus for neutron emissivity profile measurements, consists of two fan-shaped arrays of collimators and each line of sight (LOS) is equipped with a NE213 liquid organic scintillator for simultaneous measurements of the 2.5 MeV and 14 MeV neutrons. A digital system developed in ENEA has replaced the analog acquisition electronics and now enables the NPM to perform spatially resolved neutron spectrometry by providing neutron pulse height spectra (PHS) for each LOS. However, the NPM was not originally designed as a spectrometer and, therefore, lacks several key features, such as detailed measurements of the detector response functions and the presence of detector stability monitors. We present a proof of principle of ion temperature profile measurements derived from the NPM PHS in high plasma current discharges using simulated detector response functions.

  4. Monitoring of Regional Land Surface Temperature in city by Wireless Sensing Network

    Science.gov (United States)

    Wang, Y.; Jiang, H.; Jin, J.

    2015-12-01

    Land surface temperature (LST) is an important environmental factor. The precise monitoring data of LST can provide crucial support for further ecological researches such as the environment change and urban heat island. The Wireless Sensing Network (WSN) is a kind of modern information technology which integrates sensor technology, automatic control technology with data network transmission, storage, processing and analysis technology. As a new kind of data collection method, WSN is innovatively applied to monitor regional LST in different land cover types of city in this study. The LST data with high temporal resolution is obtained from temperature sensors of WSN. The land cover types of city are extracted from WorldView-II image with high resolution. The Southeast University Wuxi Branch campus and its surroundings which covers 2 km2 is chosen as the study area in Wuxi city, Jiangsu province, China. WSN is established to continuously monitor LST in real-time for one week. Then, the heterogeneous pattern of LST is investigated at a fine spatial and temporal scale based on different land cover types. The result shows LST of streets is higher than LST of campus in the daytime, but lower than LST of campus at night. The spatial heterogeneity of LST in the campus is not significant. This is because the number of vehicle was larger in the daytime than that at night, while the population of campus in day and night almost having little change. Notably, the influence of plant activities (e.g. photosynthesis and respiration) on LST can be detected by WSN. This study is a new attempt to monitor regional environment of city by WSN technology. Moreover, compared to traditional methods, WSN technology can improve the detection of LST with finer temporal and spatial resolution.

  5. Online monitoring of the two-dimensional temperature field in a boiler furnace based on acoustic computed tomography

    International Nuclear Information System (INIS)

    Zhang, Shiping; Shen, Guoqing; An, Liansuo; Niu, Yuguang

    2015-01-01

    Online monitoring of the temperature field is crucial to optimally adjust combustion within a boiler. In this paper, acoustic computed tomography (CT) technology was used to obtain the temperature profile of a furnace cross-section. The physical principles behind acoustic CT, acoustic signals and time delay estimation were studied. Then, the technique was applied to a domestic 600-MW coal-fired boiler. Acoustic CT technology was used to monitor the temperature field of the cross-section in the boiler furnace, and the temperature profile was reconstructed through ART iteration. The linear sweeping frequency signal was adopted as the sound source signal, whose sweeping frequency ranged from 500 to 3000 Hz with a sweeping cycle of 0.1 s. The generalized cross-correlation techniques with PHAT and ML were used as the time delay estimation method when the boiler was in different states. Its actual operation indicated that the monitored images accurately represented the combustion state of the boiler, and the acoustic CT system was determined to be accurate and reliable. - Highlights: • An online monitoring approach to monitor temperature field in a boiler furnace. • The paper provides acoustic CT technology to obtain the temperature profile of a furnace cross-section. • The temperature profile was reconstructed through ART iteration. • The technique is applied to a domestic 600-MW coal-fired boiler. • The monitored images accurately represent the combustion state of the boiler

  6. Diffusion characteristics of specific metals at the high temperature hydrogen separation; Diffusionseigenschaften bestimmter Metalle bei der Hochtemperatur-Wasserstoffabtrennung

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, Christian

    2010-09-07

    This paper evaluates the metals palladium, nickel, niobium, tantalum, titanium and vanadium according to their ability to separate hydrogen at high temperatures. This evaluation is chiefly based on a thorough consideration of the properties of diffusion for these metals. The various known hydrogen permeabilities of the metals in a temperature range from 300 to 800 C, as well as their physical and mechanical properties will be presented consistent with the current state of technology. The theory of hydrogen diffusion in metals and the mathematical basis for the calculation of diffusion will also be shown. In the empirical section of the paper, permeability measurements are taken in a temperature range of 400 to 825 C. After measurement, the formation of the oxide coating on these membranes is examined using a light-optical microscope. The results of these examinations allow a direct comparison of the different permeabilities of the various metals within the temperature range tested, and also allow for a critical evaluation of the oxide coating formed on the membranes. The final part of the paper shows the efficiency of these metals in the context of in-situ hydrogen separation in a biomass reformer. (orig.)

  7. Control system of reverse side bead width by surface temperature monitoring of TIG weld

    International Nuclear Information System (INIS)

    Kozono, Yuzoo; Kokura, Satoshi; Onuma, Akira

    1986-01-01

    An experimental model of a reverse side bead width control system which employs a fiber-optic thermal sensor and a microcomputer has been developed. The system is worked by monitoring infrared radiation emitted from the surface of the workpiece. In this system, infrared rays emitted from the surface of the weld are picked up and transmitted via optical fiber to a photodiode which converts them into electrical signals. The welding current is controlled by an 8-bit microcomputer in accordance with fluctuations in these signals so as to ensure the optimum surface temperature is obtained for a high quality reverse side bead. (author)

  8. Monitoring trace metals and organohalogens in shellfish (2014) and physicochemical parameters and trace metals in seawater (2015) under the Shellfish Waters Directive

    OpenAIRE

    Institute, Marine

    2017-01-01

    Directive 2006/113/EC on the Quality Required of Shellfish Waters, also referred to as the Shellfish Waters Directive (SWD) requires the monitoring of, inter alia, certain physicochemical parameters including trace metal contaminants in order to assess and protect the quality of shellfish growing waters and the shellfish harvested from them. Sixty-four areas have been designated as Shellfish Waters (SWs) under SI 268 of 2006, SI 55 of 2009 and SI 464 of 2009. The SWD is concerned the quality ...

  9. Distributed Wireless Monitoring System for Ullage and Temperature in Wine Barrels

    Science.gov (United States)

    Zhang, Wenqi; Skouroumounis, George K.; Monro, Tanya M.; Taylor, Dennis K.

    2015-01-01

    This paper presents a multipurpose and low cost sensor for the simultaneous monitoring of temperature and ullage of wine in barrels in two of the most important stages of winemaking, that being fermentation and maturation. The distributed sensor subsystem is imbedded within the bung of the barrel and runs on battery for a period of at least 12 months and costs around $27 AUD for all parts. In addition, software was designed which allows for the remote transmission and easy visual interpretation of the data for the winemaker. Early warning signals can be sent when the temperature or ullage deviates from a winemakers expectations so remedial action can be taken, such as when topping is required or the movement of the barrels to a cooler cellar location. Such knowledge of a wine’s properties or storage conditions allows for a more precise control of the final wine quality. PMID:26266410

  10. Satellite air temperature estimation for monitoring the canopy layer heat island of Milan

    DEFF Research Database (Denmark)

    Pichierri, Manuele; Bonafoni, Stefania; Biondi, Riccardo

    2012-01-01

    across the city center from June to September confirming that, in Milan, urban heating is not an occasional phenomenon. Furthermore, this study shows the utility of space missions to monitor the metropolis heat islands if they are able to provide nighttime observations when CLHI peaks are generally......In this work, satellite maps of the urban heat island of Milan are produced using satellite-based infrared sensor data. For this aim, we developed suitable algorithms employing satellite brightness temperatures for the direct air temperature estimation 2 m above the surface (canopy layer), showing...... 2007 and 2010 were processed. Analysis of the canopy layer heat island (CLHI) maps during summer months reveals an average heat island effect of 3–4K during nighttime (with some peaks around 5K) and a weak CLHI intensity during daytime. In addition, the satellite maps reveal a well defined island shape...

  11. Fiber optic sensing system for temperature and gas monitoring in coal waste pile combustion environments

    Science.gov (United States)

    Viveiros, D.; Ribeiro, J.; Ferreira, J.; Lopez-Albada, A.; Pinto, A. M. R.; Perez-Herrera, R. A.; Diaz, S.; Lopez-Gil, A.; Dominguez-Lopez, A.; Esteban, O.; Martin-Lopez, S.; Auguste, J.-L.; Jamier, R.; Rougier, S.; Silva, S. O.; Frazão, O.; Santos, J. L.; Flores, D.; Roy, P.; Gonzalez-Herraez, M.; Lopez-Amo, M.; Baptista, J. M.

    2015-09-01

    It is presented an optical fiber sensing system projected to operate in the demanding conditions associated with coal waste piles in combustion. Distributed temperature measurement and spot gas sensing are requirements for such a system. A field prototype has been installed and is continuously gathering data, which will input a geological model of the coal waste piles in combustion aiming to understand their dynamics and evolution. Results are presented on distributed temperature and ammonia measurement, being noticed any significant methane emission in the short time period considered. Carbon dioxide is also a targeted gas for measurement, with validated results available soon. The assessment of this technology as an effective and reliable tool to address the problem of monitoring coal waste piles in combustion opens the possibility of its widespread application in view of the worldwide presence of coal related fires.

  12. Distributed Wireless Monitoring System for Ullage and Temperature in Wine Barrels

    Directory of Open Access Journals (Sweden)

    Wenqi Zhang

    2015-08-01

    Full Text Available This paper presents a multipurpose and low cost sensor for the simultaneous monitoring of temperature and ullage of wine in barrels in two of the most important stages of winemaking, that being fermentation and maturation. The distributed sensor subsystem is imbedded within the bung of the barrel and runs on battery for a period of at least 12 months and costs around $27 AUD for all parts. In addition, software was designed which allows for the remote transmission and easy visual interpretation of the data for the winemaker. Early warning signals can be sent when the temperature or ullage deviates from a winemakers expectations so remedial action can be taken, such as when topping is required or the movement of the barrels to a cooler cellar location. Such knowledge of a wine’s properties or storage conditions allows for a more precise control of the final wine quality.

  13. Electromagnetic Modelling of Fiber Sensors for Low-Cost and High Sensitivity Temperature Monitoring

    Directory of Open Access Journals (Sweden)

    William Scarcia

    2015-11-01

    Full Text Available An accurate design of an innovative fiber optic temperature sensor is developed. The sensor is based on a cascade of three microstructured optical fibers (MOFs. In the first one a suitable cascade of long period gratings is designed into the core. A single mode intermediate and a rare-earth activated Fabry-Perot optical cavity are the other two sensor MOF sections. An exhaustive theoretic feasibility investigation is performed employing computer code. The complete set-up for temperature monitoring can be obtained by utilizing only a low cost pump diode laser at 980 nm wavelength and a commercial optical power detector. The simulated sensitivity S = 315.1 μW/°C and the operation range ΔT = 100 °C is good enough for actual applications.

  14. Central-peripheral Temperature Monitoring as a Marker for Diagnosing Late-onset Neonatal Sepsis.

    Science.gov (United States)

    Leante-Castellanos, José Luis; Martínez-Gimeno, Antonio; Cidrás-Pidré, Manuel; Martínez-Munar, Gerardo; García-González, Ana; Fuentes-Gutiérrez, Carmen

    2017-12-01

    The prognosis for late-onset sepsis depends largely on a timely diagnosis. We assess central-peripheral temperature difference monitoring as a marker for late-onset neonatal sepsis diagnosis. We performed a prospective, observational study focusing on a cohort of 129 very low-birth-weight infants. Thermal gradient alteration was defined as a difference of > 2°C maintained during 4 hours. We then determined its association with the late-onset sepsis variable through logistic regression. We enrolled 129 preterm babies in 52 months. Thermal gradient alterations showed an adjusted odds ratio for late-onset sepsis of 23.60 (95% confidence interval [CI], 6.80-81.88), with a sensitivity of 83% and negative predictive value of 94%. In 71% of cases, thermal gradient alteration was the first clinical sign of sepsis, while C-reactive protein was peripheral temperature differences are an early sign of evolving late-onset sepsis.

  15. High-temperature, high-pressure bonding of nested tubular metallic components

    International Nuclear Information System (INIS)

    Quinby, T.C.

    1980-01-01

    This invention is a tool for effecting high-temperature, high compression bonding between the confronting faces of nested, tubular, metallic components. In a typical application, the tool is used to produce tubular target assemblies for irradiation in nuclear reactors or particle accelerators, the target assembly comprising a uranium foil and an aluminum-alloy substrate. The tool preferably is composed throughout of graphite. It comprises a tubular restraining member in which a mechanically expandable tubular core is mounted to form an annulus with the member. The components to be bonded are mounted in nested relation in the annulus. The expandable core is formed of individually movable, axially elongated segments whose outer faces cooperatively define a cylindrical pressing surface and whose inner faces cooperatively define two opposed, inwardly tapered, axial bores. Tapered rams extend respectively into the bores. The loaded tool is mounted in a conventional hot-press provided with evacuation means, heaters for maintaining its interior at bonding temperature, and hydraulic cylinders for maintaining a selected inwardly directed pressure on the tapered rams. With the hotpress evacuated and the loaded tool at the desired temperature, the cylinders are actuated to apply the selected pressure to the rams. The rams in turn expand the segmented core to maintain the nested components in compression against the restraining member. These conditions are maintained until the confronting faces of the nested components are joined in a continuous, uniform bond characterized by high thermal conductivity

  16. Temperature dependent absorption measurement of various transition metal doped laser materials

    Science.gov (United States)

    Horackova, Lucie; Šulc, Jan; Jelinkova, Helena; Jambunathan, Venkatesan; Lucianetti, Antonio; Mocek, Tomás.

    2015-05-01

    In recent years, there has been a vast development of high energy class lasers of the order of 100 J to kJ level which have potential applications in the field of science and technology. Many such systems use the gain media cooled at cryogenic temperatures which will help in enhancing the spectroscopic and thermo-optical properties. Nevertheless, parasitic effects like amplified spontaneous emission enhance and affect the overall efficiency. The best way to suppress this effect is to use cladding element attached to the gain material. Based on these facts, this work was focused on the systematic investigation of temperature dependent absorption of several materials doped with transition metals, which can be used as cladding, as laser gain material, or as passive Q-switching element. The Ti:sapphire, Cr:YAG, V:YAG, and Co:MALO samples were measured in temperature range from 80 K to 330 K by step of 50 K. Using Beer-Lambert law we estimated the absorption coefficient of these materials.

  17. AB{sub 2} metal hydrides for high-pressure and narrow temperature interval applications

    Energy Technology Data Exchange (ETDEWEB)

    Hagstroem, M.T.; Vanhanen, J.P.; Lund, P.D. [Helsinki Univ. of Technol., Hut (Finland). Dept. of Eng. Phys. and Math.

    1998-05-01

    AB{sub 2}-based metal hydrides have been studied in order to find high-capacity, low-hysteresis alloy-hydrogen systems for high-pressure applications with strict thermal boundary conditions. TiCrMn{sub 1-3x}Fe{sub 2x}V{sub x} (x=0, 0.05, 0.1, 0.15 or 0.2) and Ti{sub 1-y}Zr{sub y}(Cr{sub z}Mn{sub 1-z}){sub 2} (y=0.05 or 0.15 and z=0.5 or 0.6) alloys have been synthesized and characterised by XRD, ICP spectrometry and volumetric PCI measurements. In addition, the PCIs of two commercial (GfE) alloys, Hydralloy C2 and Hydralloy C0, have been measured and a PDSC study on Hydralloy C2 has been performed, in order to assess the feasibility of their basic hydriding properties for narrow temperature interval applications. In the Fe and V containing alloy-hydrogen systems, hysteresis can be overcome at the cost of reduced hydriding capacity, while in the Zr-containing hydrides, at the temperatures of this study (-80 to 60 C), hysteresis is not completely eliminated but the hydriding capacity remains good also at high temperatures. The interplay between these properties of hydrides is discussed, as well as the role of materials characteristics in specially constrained applications. (orig.) 17 refs.

  18. High-temperature, high-pressure bonding of nested tubular metallic components

    Science.gov (United States)

    Quinby, T.C.

    A tool is described for effecting high-temperature, high-compression bonding between the confronting faces of nested, tubular, metallic components. In a typical application, the tool is used to produce tubular target assemblies for irradiation in nuclear reactors or particle accelerators. The target assembly comprising a uranum foil and an aluninum-alloy substrate. The tool is composed of graphite. It comprises a tubular restraining member in which a mechanically expandable tubular core is mounted to form an annulus. The components to be bonded are mounted in nested relation in the annulus. The expandable core is formed of individually movable, axially elongated segments whose outer faces cooperatively define a cylindrical pressing surface and whose inner faces cooperatively define two opposed, inwardly tapered, axial bores. Tapered rams extend into the bores. The loaded tool is mounted in a conventional hot-press provided with evacuation means, heaters for maintaining its interior at bonding temperature, and hydraulic cylinders for maintaining a selected inwardly directed pressure on the tapered rams. With the hot-press evacuated and the loaded tool at the desired temperature, the cylinders are actuated to apply the selected pressure to the rams. The rams in turn expand the segmented core to maintain the nested components in compression against the restraining member. These conditions are maintained until the confronting faces of the nested components are joined in a continuous, uniform bond characterized by high thermal conductivity.

  19. Fiber Bragg Grating Measuring System for Simultaneous Monitoring of Temperature and Humidity in Mechanical Ventilation

    Directory of Open Access Journals (Sweden)

    Carlo Massaroni

    2017-04-01

    Full Text Available During mechanical ventilation, the humidification of the dry air delivered by the mechanical ventilator is recommended. Among several solutions, heated wire humidifiers (HWHs have gained large acceptance to be used in this field. The aim of this work is to fabricate a measuring system based on fiber Bragg grating (FBG for the simultaneous monitoring of gas relative humidity (RH and temperature, intended to be used for providing feedback to the HWHs’ control. This solution can be implemented using an array of two FBGs having a different center wavelength. Regarding RH monitoring, three sensors have been fabricated by coating an FBG with two different moisture-sensitive and biocompatible materials: the first two sensors were fabricated by coating the grating with a 3 mm × 3 mm layer of agar and agarose; to investigate the influence of the coating thickness to the sensor response, a third sensor was developed with a 5 mm × 5 mm layer of agar. The sensors have been assessed in a wide range of RH (up to 95% during both an ascending and a subsequent descending phase. Only the response of the 3 mm × 3 mm-coated sensors were fast enough to follow the RH changes, showing a mean sensitivity of about 0.14 nm/% (agar-coated and 0.12 nm/% (agarose-coated. The hysteresis error was about <10% in the two sensors. The contribution of temperature changes on these RH sensors was negligible. The temperature measurement was performed by a commercial FBG insensitive to RH changes. The small size of these FBG-based sensors, the use of biocompatible polymers, and the possibility to measure both temperature and RH by using the same fiber optic embedding an array of two FBGs make intriguing the use of this solution for application in the control of HWHs.

  20. Risk-based analysis of environmental monitoring data: application to heavy metals in North Carolina surface waters.

    Science.gov (United States)

    Preston, Benjamin L; Shackelford, Jeremiah

    2002-08-01

    The state of North Carolina's Department of Environment and Natural Resources (NCDENR) conducts routine water quality monitoring throughout the state to assess the health of aquatic systems. The current study reports the results of a retrospective (1990-2000) ecological risk assessment of six heavy metals (arsenic, cadmium, copper, lead, mercury, and zinc) in 17 North Carolina basins that was conducted to estimate the risk of heavy metal toxicity to freshwater organisms and assess the sufficiency of NCDENR's monitoring data to identify water-quality-related ecological threats. Acute and chronic ecotoxicological thresholds (ETs) were calculated for each metal based upon the 10th percentile of species sensitivity distributions and were normalized for water hardness. Statewide probabilities (expressed as percentages) of a random sample exceeding acute or chronic ETs among the six metals ranged from 0.01% to 12.19% and 0.76% to 21.21%, respectively, with copper having the highest and arsenic and mercury the lowest risk. Basin-specific probabilities varied significantly depending upon water hardness and presumably watershed development. Although the majority of specific sites where data were collected were at low risk for metal toxicity, some specific sites had a high probability of toxic events associated with one or more metals. Analytical detection limits for metals were frequently higher than estimated chronic ET, limiting the ability to assess the risk of chronic toxicity in soft-water basins. Results suggest risk-based criteria may be useful for assessing and validating the sufficiency of monitoring programs and prioritizing management goals.

  1. Acoustic monitoring of sodium boiling in a liquid metal fast breeder reactor from autoregressive models

    Energy Technology Data Exchange (ETDEWEB)

    Geraldo, Issa Cherif [Laboratoire d’Automatique, Génie Informatique et Signal (LAGIS UMR CNRS 8219), Université Lille 1, Sciences et technologies, Avenue Paul Langevin, BP 48, 59651 Villeneuve d’Ascq CEDEX (France); Bose, Tanmoy [Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal (India); Pekpe, Komi Midzodzi, E-mail: midzodzi.pekpe@univ-lille1.fr [Laboratoire d’Automatique, Génie Informatique et Signal (LAGIS UMR CNRS 8219), Université Lille 1, Sciences et technologies, Avenue Paul Langevin, BP 48, 59651 Villeneuve d’Ascq CEDEX (France); Cassar, Jean-Philippe [Laboratoire d’Automatique, Génie Informatique et Signal (LAGIS UMR CNRS 8219), Université Lille 1, Sciences et technologies, Avenue Paul Langevin, BP 48, 59651 Villeneuve d’Ascq CEDEX (France); Mohanty, A.R. [Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal (India); Paumel, Kévin [CEA, DEN, Nuclear Technology Department, F-13108 Saint-Paul-lez-Durance (France)

    2014-10-15

    Highlights: • The work deals with sodium boiling detection in a liquid metal fast breeder reactor. • The authors choose to use acoustic data instead of thermal data. • The method is designed to not to be disturbed by the environment noises. • A real time boiling detection methods are proposed in the paper. - Abstract: This paper deals with acoustic monitoring of sodium boiling in a liquid metal fast breeder reactor (LMFBR) based on auto regressive (AR) models which have low computational complexities. Some authors have used AR models for sodium boiling or sodium–water reaction detection. These works are based on the characterization of the difference between fault free condition and current functioning of the system. However, even in absence of faults, it is possible to observe a change in the AR models due to the change of operating mode of the LMFBR. This sets up the delicate problem of how to distinguish a change in operating mode in absence of faults and a change due to presence of faults. In this paper we propose a new approach for boiling detection based on the estimation of AR models on sliding windows. Afterwards, classification of the models into boiling or non-boiling models is made by comparing their coefficients by two statistical methods, multiple linear regression (LR) and support vectors machines (SVM). The proposed approach takes into account operating mode information in order to avoid false alarms. Experimental data include non-boiling background noise data collected from Phenix power plant (France) and provided by the CEA (Commissariat à l’Energie Atomique et aux énergies alternatives, France) and boiling condition data generated in laboratory. High boiling detection rates as well as low false alarms rates obtained on these experimental data show that the proposed method is efficient for boiling detection. Most importantly, it shows that the boiling phenomenon introduces a disturbance into the AR models that can be clearly detected.

  2. Internal and External Temperature Monitoring of a Li-Ion Battery with Fiber Bragg Grating Sensors

    Directory of Open Access Journals (Sweden)

    Susana Novais

    2016-08-01

    Full Text Available The integration of fiber Bragg grating (FBG sensors in lithium-ion cells for in-situ and in-operando temperature monitoring is presented herein. The measuring of internal and external temperature variations was performed through four FBG sensors during galvanostatic cycling at C-rates ranging from 1C to 8C. The FBG sensors were placed both outside and inside the cell, located in the center of the electrochemically active area and at the tab-electrode connection. The internal sensors recorded temperature variations of 4.0 ± 0.1 °C at 5C and 4.7 ± 0.1 °C at 8C at the center of the active area, and 3.9 ± 0.1 °C at 5C and 4.0 ± 0.1 °C at 8C at the tab-electrode connection, respectively. This study is intended to contribute to detection of a temperature gradient in real time inside a cell, which can determine possible damage in the battery performance when it operates under normal and abnormal operating conditions, as well as to demonstrate the technical feasibility of the integration of in-operando microsensors inside Li-ion cells.

  3. Novel Concrete Temperature Monitoring Method Based on an Embedded Passive RFID Sensor Tag.

    Science.gov (United States)

    Liu, Yongsheng; Deng, Fangming; He, Yigang; Li, Bing; Liang, Zhen; Zhou, Shuangxi

    2017-06-22

    This paper firstly introduces the importance of temperature control in concrete measurement, then a passive radio frequency identification (RFID) sensor tag embedded for concrete temperature monitoring is presented. In order to reduce the influences of concrete electromagnetic parameters during the drying process, a T-type antenna is proposed to measure the concrete temperature at the required depth. The proposed RFID sensor tag is based on the EPC generation-2 ultra-high frequency (UHF) communication protocol and operates in passive mode. The temperature sensor can convert the sensor signals to corresponding digital signals without an external reference clock due to the adoption of phase-locked loop (PLL)-based architecture. Laboratory experimentation and on-site testing demonstrate that our sensor tag embedded in concrete can provide reliable communication performance in passive mode. The maximum communicating distance between reader and tag is 7 m at the operating frequency of 915 MHz and the tested results show high consistency with the results tested by a thermocouple.

  4. Foraminiferal single chamber analyses of heavy metals as a tool for monitoring permanent and short term anthropogenic footprints.

    Science.gov (United States)

    Titelboim, Danna; Sadekov, Aleksey; Hyams-Kaphzan, Orit; Almogi-Labin, Ahuva; Herut, Barak; Kucera, Michal; Abramovich, Sigal

    2018-03-01

    In order to establish environmentally sustainable industries there is a need for high-resolution temporal and spatial monitoring of heavy metal pollutants even at low concentrations before they become hazardous for local ecosystems. Here we present single chamber records of Cu, Zn and Pb in shells of two benthic foraminifera species with different shell types from two shallow coastal stations in Israel: An area adjacent to an electrical power plant and desalination factory (Hadera) and an industrially free nature reserve (Nachsholim). Records of both foraminifera species show elevated metal concentrations in Hadera clearly identifying the footprint of the local industrial facilities. Moreover, short-term events of elevated Cu and Pb concentrations were detected by single chamber analyses. This study demonstrates the potential of using heavy metals anomalies in foraminiferal single chambers as a tool for detecting the industrial footprint of coastal facilities as well as short term events of elevated heavy metals. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. High temperature corrosion in straw-fired power plants: Influence of steam/metal temperature on corrosion rates for TP347H

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Biede, O; Larsen, OH

    2002-01-01

    The corrosion in straw-fired boilers has been investigated at various straw-fired power plants in Denmark. Water/air-cooled probes, a test superheater and test sections removed from the actual superheater have been utilised to characterise corrosion and corrosion rates. This paper describes...... the corrosion rates measured for the TP347H type steel. The corrosion morphology at high temperature consists of grain boundary attack and selective attack of chromium. The corrosion rate increases with calculated metal temperature (based on steam temperature), however there is great variation within...... these results. In individual superheaters, there are significant temperature variations i.e. higher temperature in middle banks compared to the outer banks, higher temperature in leading tubes, which have a high impact on corrosion. In a single loop the assumption that heat uptake (and heat flux) is linear...

  6. Monitoring on Heavy Metals Content in Sea Water and Sediment in the Waters of Bacan Island, North of Maluku

    Directory of Open Access Journals (Sweden)

    Febriana Lisa Valentin

    2010-04-01

    Full Text Available Measurement on heavy metals content in seawater and sediment in the waters of Bacan Islands, North of Maluku were carried out in September 2005. That heavy metals are Pb, Cd, Cu, Zn, and Ni. Seawater and sediment sample collected from 10 station by purposive sampling, in line with the goal of the research. The results showed that the heavy metals content in seawater still in line with the threshold value (NAB stated by The Office of State Ministry for Life Environment (KMNLH but in sediment heavy metals content is high relative, especially Cu and Ni has passed the threshold value for sediment. Beside heavy metal content also measured physical and chemical parameters such as temperature, salinity, total suspended solid, light transmission, dissolved oxygen, acidity, phosphate and nitrate. The result also indicated that parameters still in line with the threshold value stated by KMNLH for marine organism. Based on heavy metals content, the value of seawater quality status included into class A (fine with score 0. Heavy metal content in sediment is higher than seawater, this condition indicated there are heavy metals accumulation in sediment.

  7. Self propagating high temperature synthesis of metal oxides. Reactions in external magnetic fields

    CERN Document Server

    Aguas, M D

    2001-01-01

    The preparation of metal oxides by Self-Propagating High-Temperature Synthesis is reported. The reactions are started with a point source of ignition; typically a hot wire. A synthesis wave is observed moving out from the point source and reactions terminate in seconds. Products obtained can be classified into ferrites (magnetic applications) and stannates (gas sensing applications). Ferrites were synthesised under variable external magnetic fields. The synthesis wave is hotter in the presence of an external magnetic field for hard ferrite synthesis. For spinel ferrites the opposite was observed. Materials synthesised in the field show differences in their bulk magnetic properties (coercivity and saturation magnetisation), structures and microstructures. Combustion reactions in large fields revealed changes in unit cell volume (shrinkage was observed for hard ferrites while expansion was observed for spinel ferrites). SHS synthesised hard ferrites show two distinct components; one has large grain structure co...

  8. Characterization of low temperature metallic magnetic calorimeters having gold absorbers with implanted $^{163}$Ho ions

    CERN Document Server

    Gastaldo, L.; von Seggern, F.; Porst, J.-P.; Schäfer, S.; Pies, C.; Kempf, S.; Wolf, T.; Fleischmann, A.; Enss, C.; Herlert, A.; Johnston, K.

    2013-01-01

    For the first time we have investigated the behavior of fully micro-fabricated low temperature metallic magnetic calorimeters (MMCs) after undergoing an ion-implantation process. This experiment had the aim to show the possibility to perform a high precision calorimetric measurement of the energy spectrum following the electron capture of $^{163}$Ho using MMCs having the radioactive $^{163}$Ho ions implanted in the absorber. The implantation of $^{163}$Ho ions was performed at ISOLDE-CERN. The performance of a detector that underwent an ion-implantation process is compared to the one of a detector without implanted ions. The results show that the implantation dose of ions used in this experiment does not compromise the properties of the detector. In addition an optimized detector design for future $^{163}$Ho experiments is presented.

  9. Standard test methods for elevated temperature tension tests of metallic materials

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 These test methods cover procedure and equipment for the determination of tensile strength, yield strength, elongation, and reduction of area of metallic materials at elevated temperatures. 1.2 Determination of modulus of elasticity and proportional limit are not included. 1.3 Tension tests under conditions of rapid heating or rapid strain rates are not included. 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  10. Size Effect Suppresses Brittle Failure in Hollow Cu60Zr40 Metallic Glass Nanolattices Deformed at Cryogenic Temperatures.

    Science.gov (United States)

    Lee, Seok-Woo; Jafary-Zadeh, Mehdi; Chen, David Z; Zhang, Yong-Wei; Greer, Julia R

    2015-09-09

    To harness "smaller is more ductile" behavior emergent at nanoscale and to proliferate it onto materials with macroscale dimensions, we produced hollow-tube Cu60Zr40 metallic glass nanolattices with the layer thicknesses of 120, 60, and 20 nm. They exhibit unique transitions in deformation mode with tube-wall thickness and temperature. Molecular dynamics simulations and analytical models were used to interpret these unique transitions in terms of size effects on the plasticity of metallic glasses and elastic instability.

  11. Low temperature synthesis of ternary metal phosphides using plasma for asymmetric supercapacitors

    KAUST Repository

    Liang, Hanfeng

    2017-04-06

    We report a versatile route for the preparation of metal phosphides using PH plasma for supercapacitor applications. The high reactivity of plasma allows rapid and low temperature conversion of hydroxides into monometallic, bimetallic, or even more complex nanostructured phosphides. These same phosphides are much more difficult to synthesize by conventional methods. Further, we present a general strategy for significantly enhancing the electrochemical performance of monometallic phosphides by substituting extrinsic metal atoms. Using NiCoP as a demonstration, we show that the Co substitution into NiP not only effectively alters the electronic structure and improves the intrinsic reactivity and electrical conductivity, but also stabilizes Ni species when used as supercapacitor electrode materials. As a result, the NiCoP nanosheet electrodes achieve high electrochemical activity and good stability in 1 M KOH electrolyte. More importantly, our assembled NiCoP nanoplates//graphene films asymmetric supercapacitor devices can deliver a high energy density of 32.9 Wh kg at a power density of 1301 W kg, along with outstanding cycling performance (83% capacity retention after 5000 cycles at 20 A g). This activity outperforms most of the NiCo-based materials and renders the NiCoP nanoplates a promising candidate for capacitive storage devices.

  12. A Novel Temperature Monitoring Sensor for Gas-Based Detectors in Large HEP Experiments

    Science.gov (United States)

    Benussi, L.; Bianco, S.; Caponero, M. A.; Colafranceschi, S.; Ferrini, M.; Felli, F.; Passamonti, L.; Pierluigi, D.; Polimadei, A.; Russo, A.; Saviano, G.; Vendittozzi, C.

    Gaseous detectors are commonly used in HEP (High Energy Physics) experiments to reconstruct the track of elementary particles. They are often made by a very large number of chambers with relatively small individual volume, arranged in thick layers placed approximately all around the vertex of the experiment in order to detect elementary particles produced in any direction. The large volume of gas inside the detector must be monitored for many parameters as they can affect both the efficiency and the working life of the detector. The temperature of the gas inside the individual chambers is a critical parameter to be monitored, as it can both affect the efficiency of the detector and point out on-board electronic circuitry overheating. In this paper we propose a novel gas temperature sensing system based on optical fibre technology. The adopted technology is well suited to make distributed sensing systems with large number of sensors, it is immune to electromagnetic disturbances and it has adequate radiation hardness. A prototype of the basic sensor of the proposed system was tested at the experimental facility for Resistive Plate Chamber characterization available at the INFN laboratories in Frascati. Results are presented and discussed.

  13. Metal electrodeposition and electron transfer studies of uranium compounds in room temperature ionic liquids

    International Nuclear Information System (INIS)

    Stoll, M.E.; Oldham, W.J.; Costa, D.A.

    2004-01-01

    Room temperature ionic liquids (RTIL's) comprised of 1,3-dialkylimidazolium or quaternary ammonium cations and one of several anions such as PF 6 - , BF 4 - , or - N(SO 2 CF 3 ) 2 , represent a class of solvents that possess great potential for use in applications employing electrochemical procedures. Part of the intrigue with RTIL's stems from some of their inherent solvent properties including negligible vapor pressure, good conductivity, high chemical and thermal stability, and non-flammability. Additionally, a substantial number of RTIL's can be envisioned simply by combining different cation and anion pairs, thereby making them attractive for specific application needs. We are interested in learning more about the possible use of RTIL's within the nuclear industry. In this regard our research team has been exploring the electron transfer behavior of simple metal ions in addition to coordination and organometallic complexes in these novel solvents. Results from our research have also provided us with insight into the bonding interactions between our current anion of choice, bis(trifluoromethylsulfonyl)imide = NTf 2 , and open coordination sites on actinide and transition metal fragments. This presentation will focus on recent results in two areas: the electrodeposition of electropositive metal ions from RTIL solutions and the electron transfer behavior for several uranium complexes. Details concerning the cathodic electrodeposition and anodic stripping of alkali metals (Na, K) from various working electrode surfaces (Pt, Au, W, Glassy Carbon) will be discussed. Figure 1 displays typical behavior for the electrodeposition of potassium metal from an RTIL containing potassium ions produced through the reaction of KH with H[NTf 2 ]. Our efforts with other metal ions, including our results to date with uranium electrodeposition, will be covered during the presentation. The electron transfer behavior for a number of uranium complexes have been studied with various

  14. Impact Analysis of Temperature and Humidity Conditions on Electrochemical Sensor Response in Ambient Air Quality Monitoring.

    Science.gov (United States)

    Wei, Peng; Ning, Zhi; Ye, Sheng; Sun, Li; Yang, Fenhuan; Wong, Ka Chun; Westerdahl, Dane; Louie, Peter K K

    2018-01-23

    The increasing applications of low-cost air sensors promises more convenient and cost-effective systems for air monitoring in many places and under many conditions. However, the data quality from such systems has not been fully characterized and may not meet user expectations in research and regulatory uses, or for use in citizen science. In our study, electrochemical sensors (Alphasense B4 series) for carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO₂), and oxidants (O x ) were evaluated under controlled laboratory conditions to identify the influencing factors and quantify their relation with sensor outputs. Based on the laboratory tests, we developed different correction methods to compensate for the impact of ambient conditions. Further, the sensors were assembled into a monitoring system and tested in ambient conditions in Hong Kong side-by-side with regulatory reference monitors, and data from these tests were used to evaluate the performance of the models, to refine them, and validate their applicability in variable ambient conditions in the field. The more comprehensive correction models demonstrated enhanced performance when compared with uncorrected data. One over-arching observation of this study is that the low-cost sensors may promise excellent sensitivity and performance, but it is essential for users to understand and account for several key factors that may strongly affect the nature of sensor data. In this paper, we also evaluated factors of multi-month stability, temperature, and humidity, and considered the interaction of oxidant gases NO₂ and ozone on a newly introduced oxidant sensor.

  15. Temperature profile detector

    Science.gov (United States)

    Tokarz, Richard D.

    1983-01-01

    Temperature profiles at elevated temperature conditions are monitored by use of an elongated device having two conductors spaced by the minimum distance required to normally maintain an open circuit between them. The melting point of one conductor is selected at the elevated temperature being detected, while the melting point of the other is higher. As the preselected temperature is reached, liquid metal will flow between the conductors, creating short circuits which are detectable as to location.

  16. Temperature-profile detector

    Science.gov (United States)

    Not Available

    1981-01-29

    Temperature profiles at elevated temperature conditions are monitored by use of an elongated device having two conductors spaced by the minimum distance required to normally maintain an open circuit between them. The melting point of one conductor is selected at the elevated temperature being detected, while the melting point of the other is higher. As the preselected temperature is reached, liquid metal will flow between the conductors creating short circuits which are detectable as to location.

  17. Temperature Evaluation of Heat Transferring Body while Preparing Temperature Chart of Heating Technologies and Metal Thermal Treatment

    Directory of Open Access Journals (Sweden)

    A. P. Nesenchuk

    2011-01-01

    Full Text Available The paper considers problems pertaining to temperature evaluation of a heat transferring body in the operational space of high temperature installations. A formula for evaluation of this temperature has been written down in the paper. Calculation of a heating transferring body (furnace makes it possible to realize temperature chart parameters in the plant heating technologies and steel thermal treatment.

  18. Weather radar performance monitoring using a metallic-grid ground-scatterer

    Science.gov (United States)

    Falconi, Marta Tecla; Montopoli, Mario; Marzano, Frank Silvio; Baldini, Luca

    2017-10-01

    The use of ground return signals is investigated for checks on the calibration of power measurements of a polarimetric C-band radar. To this aim, a peculiar permanent single scatterer (PSS) consisting of a big metallic roof with a periodic mesh grid structure and having a hemisphere-like shape is considered. The latter is positioned in the near-field region of the weather radar and its use, as a reference calibrator, shows fairly good results in terms of reflectivity and differential reflectivity monitoring. In addition, the use of PSS indirectly allows to check for the radar antenna de-pointing which is another issue usually underestimated when dealing with weather radars. Because of the periodic structure of the considered PSS, simulations of its electromagnetic behavior were relatively easy to perform. To this goal, we used an electromagnetic Computer-Aided-Design (CAD) with an ad-hoc numerical implementation of a full-wave solution to model our PSS in terms of reflectivity and differential reflectivity factor. Comparison of model results and experimental measurements are then shown in this work. Our preliminary investigation can pave the way for future studies aiming at characterizing ground-clutter returns in a more accurate way for radar calibration purposes.

  19. The Navruz Project: Transboundary Monitoring for Radionuclides and Metals in Central Asia Rivers. Data Report

    Energy Technology Data Exchange (ETDEWEB)

    Passell, Howard D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Barber, David S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Betsill, J. David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Littlefield, Adriane C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mohagheghi, Amir H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Shanks, Sonoya T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Yuldashev, Bekhzad [Inst. of Nuclear Physics, Tashkent (Uzbekistan); Saalikhbaev, Umar [Inst. of Nuclear Physics, Tashkent (Uzbekistan); Radyuk, Raisa [Inst. of Nuclear Physics, Tashkent (Uzbekistan); Djuraev, Akram [Tajik Academy of Sciences, Dushanbe (Tajikistan); Djuraev, Anwar [Tajik Academy of Sciences, Dushanbe (Tajikistan); Vasilev, Ivan [Inst. of Physics, Bishkek (Kyrgyzstan); Tolongutov, Bajgabyl [Inst. of Physics, Bishkek (Kyrgyzstan); Valentina, Alekhina [Inst. of Physics, Bishkek (Kyrgyzstan); Solodukhin, Vladimir [Inst. of Nuclear Physics, Almaty (Kazakhstan); Pozniak, Victor [Inst. of Nuclear Physics, Almaty (Kazakhstan)

    2003-04-01

    The Navruz Project is a cooperative, transboundary, river monitoring project involving rivers and institutions in Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan, and facilitated by Sandia National Laboratories in the U.S. The Navruz Project focuses on waterborne radionuclides and metals because of their importance to public health and nuclear materials proliferation concerns in the region. The Project also collects data on basic water quality parameters. Data obtained in this project are shared among all participating countries and the public through a world-wide web site (http://www.cmc.sandia.org/Central/centralasia.html), and are available for use in further studies and in regional transboundary water resource management efforts. This report includes graphs showing selected data from the Fall 2000 and Spring 2001 sampling seasons. These data include all parameters grouped into six regions, including main rivers and some tributaries in the Amu Darya and Syr Darya river systems. This report also assembles all data (in tabular form) generated by the project from Fall 2000 through Fall 2001. This report comes as the second part of a planned three-part reporting process. The first report is the Sampling and Analysis Plan and Operational Manual, SAND 2002-0484. This is the second report.

  20. Climate-monitoring CubeSat mission (CM2): a project for global mesopause temperature sensing

    Science.gov (United States)

    Doe, Richard A.; Watchorn, Steven

    2011-10-01

    The goals of the Climate Monitoring CubeSat Mission (CM2) are to accelerate climate projection by obtaining global temperature, tidal and wave measurements with a simple CubeSat-based imaging spectrograph; and to demonstrate how a high-resolution imaging spectrograph can be deployed on a CubeSat satellite. In the middle atmosphere (50 - 100 km), beyond the reach of balloons or satellites, thermal signatures of CO2 radiation and wave activity have been largely missing from climate model inputs. This paper outlines an instrument to advance the state of the art in atmospheric climate projection by providing critical global measurements of middle-atmosphere temperatures and waves with a CubeSatscale imaging spectrograph. The CM2 will remotely sense middle-atmosphere temperatures and waves at ~90 km by analyzing spectra of intrinsically bright molecular oxygen emissions at near-infrared wavelengths in the O2 atmospheric band. The core instrument will be a miniaturized imaging spectrograph based on a monolithic spatial heterodyne spectrometer (SHS). This spectrograph will have sensitivity and spectral resolution to extract temperatures with 10° K precision and waves with 4 km scale resolution along a ~200 km cross-track swath. The SHS is significantly more robust than conventional interferometers, and thus better suited to space-based observation. Acquiring high-resolution middle-atmosphere temperature, tidal, and wave data on a daily, global basis will significantly improve climate models, and will help assess long-term greenhouse gas mitigation policy impact on upper-atmosphere thermal signatures. The CM2 program will also establish the efficacy of highresolution CubeSat-based broadband (near-IR to UV) spectroscopy for application to other atmospheric research missions.