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Sample records for thermophysical properties application

  1. Thermophysical properties

    Energy Technology Data Exchange (ETDEWEB)

    Kayser, R.F.

    1992-10-01

    Numerous fluids have been identified as promising alternative refrigerants, but much of the information needed to predict their behavior as pure fluids and as components in mixtures does not exist. In particular, reliable thermophysical properties data and models are needed to predict the performance of the new refrigerants in heating and cooling equipment, and to design and optimize equipment to be reliable and energy efficient. Objective of this project is to provide highly accurate, selected thermophysical properties data for Refrigerants 32, 123, 124, and 125, and to use these data to fit simple and complex equations of state and detailed transport property models. The new data will fill gaps in the existing data sets and resolve the problems and uncertainties that exist in and between the data sets. This report describes the progress made during the third quarter of this fifteen-month project, which was initiated in late January, 1992.

  2. Thermophysical properties

    Energy Technology Data Exchange (ETDEWEB)

    Kayser, R.F.

    1993-01-01

    Numerous fluids have been identified as promising alternative refrigerants, but much of the information needed to predict their behavior as pure fluids and as components in mixtures does not exist. In particular, reliable thermophysical properties data and models are needed to predict the performance of the new refrigerants in heating and cooling equipment and to design and optimize equipment to be reliable and energy efficient. The objective of this project is to provide highly accurate, selected thermophysical properties data for Refrigerants 32, 123, 124, and 125, and to use these data to fit simple and complex equations of state and detailed transport property models. The new data will fill gaps in the existing data sets and resolve the problems and uncertainties that exist in and between the data sets. This report describes the progress made during the fourth quarter of this fifteen-month project, which was initiated in late January, 1992.

  3. Thermophysical properties; Proprietes thermophysiques

    Energy Technology Data Exchange (ETDEWEB)

    Henry, J.F.; Chirtoc, M. [Faculte des Sciences de Reims, Lab. de ThermoPhysique URCA/UTAP/LTP, EA 3802, 51 - Reims (France); Nguyen, C.T.; Roy, G.; Lajoie, P.R. [Moncton Univ., Faculte d' Ingenierie, E1A 3E9 (Canada); Popescu, B.; Garnier, B.; Feuillet, V.; Jarny, Y.; Mokrani, O.; Bourouga, B.; Castelain, C.; Peerhossaini, H. [Nantes Univ., Ecole Polytechnique, Lab. de Thermocinetique UMR CNRS 6607, 44 (France); Scudeller, Y.; Brousse, T. [Nantes Univ., Ecole Polytechnique, Lab. Genie des Materiaux, 44 (France); Tessier, P.Y. [Nantes Univ., Ecole Polytechnique, Lab. de Plasma et Couches Minces, 44 (France); Nguyen, T.P. [Institut des Materiaux Jean Rouxel UMR 6502, 44 - Nantes (France); Scudeller, Y. [Nantes Univ., Ecole Polytechnique, Lab. de Genie des Materiaux, 44 (France); Serio, B.; Teyssieux, D.; Cretin, B. [Institut FEMTO-ST/UMR-CNRS 6174, Dept. L.P.M.O., 25 - Besancon (France); Hunsinger, J.J. [Centre de Recherche sur les Ecoulements, Surfaces et Transferts, 90 - Belfort (France); Landemarre, O. [Laboratoire d' Etudes et de Recherches sur les Materiaux, les Plasmas et les Surfaces UTBM, 90 - Belfort (France); Herve, P. [Paris-10 Univ., Lab. d' Energetique et d' Economie d' Energie, 92 - Ville-d' Avray (France); Grigorova, V.; Roussev, D. [Varne Univ. Technique, Dept. de Genie de la Chaleur (Bulgaria); Grigorova, V.; Deniard, P.; Jobic, S. [Institut des Materiaux Jean Rouxel, Lab. de Chimie des Solides, 44 - Nantes (France)

    2005-07-01

    This session about thermophysical properties gathers 26 papers dealing with: thermal microscopy in alternative mode - infrared thermography analysis of the influence of the probe-sample contact resistance on the thermal state of the probe; high efficiency cooling of microprocessors using nano-fluids; thermal characterization of polymer coatings and textured interfaces; assemblies design for an optimum heat management inside power components; development of a method of measurement of the convection coefficient at the inlet of a flat micro-channel; evaluation of the operation temperature of microelectronic components by photon counting camera and synchronous video detection; synchronous thermography characterization in the visible spectrum of the surface pickling laser spot before thermal projection coating; preciseness of the empirical equations establishing the relation between the particles size and the degree of irreversibility of the synthesis thermal treatment: the case of LiCOPO{sub 4}; cooling of a microstructure by forced laminar convection; 2D analytical solution of the non-stationary heat transfer inside a dual-layer material with imperfect contact; inverse method applied to the mass transfer by convection-diffusion: application to the determination of the 'true' parietal velocity gradient during a pulsed flow; infrared thermography study of the heat flux change generated by the ultrasonic shot-blasting of a steel sheet; Bayesian parametric estimation of the convective coefficient of a roof complex; very high temperature measurement of the heat capacity of fibers; thermal conductivity of cement-rubber composites at different degrees of water saturation: experimental study and modeling; characterization of thermo-degradable composite materials; defect characterization by random photothermal radiometry; thermal conductivity measurement of insulating materials with respect to temperature; defects identification by thermographic films analysis using

  4. Analytical expressions for thermophysical properties of solid and liquid tungsten relevant for fusion applications

    Directory of Open Access Journals (Sweden)

    P. Tolias

    2017-12-01

    Full Text Available The status of the literature is reviewed for several thermophysical properties of pure solid and liquid tungsten which constitute input for the modelling of intense plasma-surface interaction phenomena that are important for fusion applications. Reliable experimental data are analyzed for the latent heat of fusion, the electrical resistivity, the specific isobaric heat capacity, the thermal conductivity and the mass density from the room temperature up to the boiling point of tungsten as well as for the surface tension and the dynamic viscosity across the liquid state. Analytical expressions of high accuracy are recommended for these thermophysical properties that involved a minimum degree of extrapolations. In particular, extrapolations were only required for the surface tension and viscosity.

  5. Thermophysical Properties of 60-NITINOL for Mechanical Component Applications

    Science.gov (United States)

    Stanford, Malcolm K.

    2012-01-01

    The linear thermal expansion coefficient, specific heat capacity, electrical resistivity and thermal conductivity of 60- NITINOL were studied over a range of temperatures representing the operating environment of an oil-lubricated bearing. The behavior of this material appears to follow wellestablished theories applicable to either metal alloys, in general, or to intermetallic compounds, more specifically and the measured data were found to be comparable to those for conventional bearing alloys.

  6. Thermophysical Properties of Hydrocarbon Mixtures

    Science.gov (United States)

    SRD 4 NIST Thermophysical Properties of Hydrocarbon Mixtures (PC database for purchase)   Interactive computer program for predicting thermodynamic and transport properties of pure fluids and fluid mixtures containing up to 20 components. The components are selected from a database of 196 components, mostly hydrocarbons.

  7. Thermophysical properties of uranium dioxide

    International Nuclear Information System (INIS)

    Fink, J.K.

    2000-01-01

    Experimental data on thermodynamic and transport properties of solid and liquid UO 2 have been reviewed and analyzed to obtain consistent equations for the thermophysical properties. Thermodynamic properties that have been assessed include enthalpy, heat capacity, enthalpy of fusion, thermal expansion, density, surface tension and vapor pressure. Transport properties that have been assessed are thermal diffusivity, thermal conductivity, viscosity, emissivity and optical constants. The assessments include a review of the experiments and data, review of previous recommendations, analysis of data to obtain new recommendations, determination of uncertainties in the recommended values, and comparisons of new recommendations with data and previous recommendations

  8. Thermophysical properties of sodium

    International Nuclear Information System (INIS)

    Harant, M.

    1978-01-01

    Substitution, inverse and substitution inverse relations in form of regression polynomials were used in calculating saturation pressure and density for thermodynamic and transport properties determination of sodium. Program UNISOAUT/A3 was used in calculating regression polynomials coefficients. (J.P.)

  9. Thermophysical properties of argon

    Energy Technology Data Exchange (ETDEWEB)

    Jaques, A.

    1988-02-01

    The entire report consists of tables of thermodynamic properties (including sound velocity, thermal conductivity and diffusivity, Prandtl number, density) of argon at 86 to 400/degree/K, in the form of isobars over 0.9 to 100 bars. (DLC)

  10. Thermophysical properties of Conasauga shale

    International Nuclear Information System (INIS)

    Smith, D.D.

    1978-01-01

    Thermophysical-property characterizations of five Conasauga shale cores were determined at temperatures between 298 and 673 K. Methods of specimen fabrication for different tests were evaluated. Thermal-conductivity and thermal-expansion data were found to be dependent on the structure and orientation of the individual specimens. Thermal conductivities ranged between 2.8 and 1.0 W/m-K with a small negative temperature dependence. Thermal expansions were between 2 and 5 x 10 -3 over the temperature range for the group. Heat capacity varied with the composition. 17 figures, 3 tables

  11. Microstructural and thermophysical properties of U–6 wt.%Zr alloy for fast reactor application

    International Nuclear Information System (INIS)

    Kaity, Santu; Banerjee, Joydipta; Nair, M.R.; Ravi, K.; Dash, Smruti; Kutty, T.R.G.; Kumar, Arun; Singh, R.P.

    2012-01-01

    Highlights: ► Characterization of U–6%Zr alloy prepared by injection casting route. ► Martensitic to non-martensitic transformation of U–6%Zr alloy occurs at 843 K. ► Specific heat versus temperature curve shows a phase transition at 845 K. ► Average coefficient of thermal expansion is 18.28 × 10 −6 K −1 (298–823 K). ► Hardness versus temperature plot shows a transition at 748 K. - Abstract: The microstructural and high temperature behavior of U–6 wt.%Zr alloy has been investigated in this study. U–6 wt.%Zr alloy sample for this study was prepared by following injection casting route. The thermophysical properties like coefficient of thermal expansion, specific heat, thermal conductivity of the above alloy were determined. The hot-hardness data of the U–6 wt.%Zr alloy was also generated from room temperature to 973 K. Apart from that, the fuel-clad chemical compatibility with T91 grade steel was also studied by diffusion couple experiment. No studies have been reported on U–6 wt.%Zr alloy. This paper aims at filling up the gap on characterization and thermophysical property evaluation of U–6 wt.%Zr alloy.

  12. Thermophysical Properties and Phase Behavior of Fluids for Application in Carbon Capture and Storage Processes.

    Science.gov (United States)

    Trusler, J P Martin

    2017-06-07

    Phase behavior and thermophysical properties of mixtures of carbon dioxide with various other substances are very important for the design and operation of carbon capture and storage (CCS) processes. The available empirical data are reviewed, together with some models for the calculation of these properties. The systems considered in detail are, first, mixtures of carbon dioxide, water, and salts; second, carbon dioxide-rich nonelectrolyte mixtures; and third, mixtures of carbon dioxide with water and amines. The empirical data and the plethora of available models permit the estimation of key fluid properties required in the design and operation of CCS processes. The engineering community would benefit from the further development, and delivery in convenient form, of a small number of these models sufficient to encompass the component slate and operating conditions of CCS processes.

  13. Characterization of thermophysical properties of phase change materials for non-membrane based indirect solar desalination application

    International Nuclear Information System (INIS)

    Sarwar, J.; Mansoor, B.

    2016-01-01

    Highlights: • Thermal cycling of paraffin waxes phase change materials. • Differential Scanning Calorimetry and thermogravimetric study of the materials. • Characterization of the phase change materials via Temperature History Method. • Investigation of suitability of materials for indirect solar desalination system. • Paraffin waxes are suitable for non-membrane indirect solar desalination system. - Abstract: Phase change material as a thermal energy storage medium has been widely incorporated in various technologies like solar air/water heating, buildings, and desalination for efficient use and management of fluctuating solar energy. Temperature and thermal energy requirements dictate the selection of an appropriate phase change material for its application in various engineering systems. In this work, two phase change materials belonging to organic paraffin wax class have been characterized to obtain their thermophysical properties. The melting/solidification temperatures, latent heat of fusion and heat capacities of the phase change materials have been investigated using Differential Scanning Calorimetry, Thermogravimetric analysis and Temperature History Method. Thermal cycles up to 300 are performed to investigate melting and solidification reversibility as well as degradation over time. It is shown that the selected paraffin waxes have reversible phase change with no degradation of thermophysical properties over time. It is also shown that melting/solidification temperature and thermal energy storage capabilities make them suitable for their application as a thermal energy storage medium, in high temperature vapour compression, multi-stage flash and multi-effect distillation processes of non-membrane based indirect desalination systems.

  14. Determination of the thermophysical properties of evolutive porous media: application to Civil Engineering materials

    Science.gov (United States)

    Poullain, P.; Mounanga, P.; Bastian, G.; Coué, R.

    2006-01-01

    The purpose of this paper is to describe the development and the use of two measurement techniques especially adapted to the rapid determination of the thermophysical properties of evolutive porous media. The first technique exploits the method of the “heated and non-heated wires” and is validated on wet clay by comparison with previous works [Mounanga et al., Eur. Phys. J. Appl. Phys. 26, 65 (2004)]. It is then used to quantify the evolution of both thermal conductivity and volumetric heat capacity of hardening cement pastes maintained at 294 ± 1 K. The second technique is based on the classical method of the “heating film” and a data treatment using forward calculation. This technique is first used to measure the properties of well-known materials (hardened mortars, wet sand [Mounanga et al., Eur. Phys. J. Appl. Phys. 26, 65 (2004); Delacre, Ph.D. thesis, University of Artois, 2000] and glass [Bastian, Rev. Phys. Appl. 22, 431 (1987)] and then applied to media whose properties evolve both over time and through space (drying sand).

  15. The thermophysical properties of metallic liquids

    CERN Document Server

    Iida, Takamichi

    2015-01-01

    The main purpose of materials science and engineering is to make the best use of all the elements in the periodic table. This leads to the effective use and conservation of natural resources. For this purpose, in any liquid metallic processing operation, accurate data for the thermophysical properties of all metallic liquids (i.e. liquid metals, semimetals, and semiconductors) is needed. However, in addition, a clear understanding of the essence of their thermophysical properties, based on these data, is indispensable. The second volume continues from the first volume to provide explanations for the thermophysical properties of metallic liquids. The two volumes identify new dimensionless parameters, extracted from the velocity of sound. In spite of being simple parameters, they provide useful information on the nature and behaviour of metallic liquids. This volume covers several basic concepts needed to understand the thermophysical properties of metallic liquids and for developing reliable models to accurate...

  16. Thermophysical Properties of Liquid Aluminum

    Science.gov (United States)

    Leitner, Matthias; Leitner, Thomas; Schmon, Alexander; Aziz, Kirmanj; Pottlacher, Gernot

    2017-06-01

    Ohmic pulse-heating with sub-microsecond time resolution is used to obtain thermophysical properties for aluminum in the liquid phase. Measurement of current through the sample, voltage drop across the sample, surface radiation, and volume expansion allow the calculation of specific heat capacity and the temperature dependencies of electrical resistivity, enthalpy, and density of the sample at melting and in the liquid phase. Thermal conductivity and thermal diffusivity as a function of temperature are estimated from resistivity data using the Wiedemann-Franz law. Data for liquid aluminum obtained by pulse-heating are quite rare because of the low melting temperature of aluminum with 933.47 K (660.32 °C), as the fast operating pyrometers used for the pulse-heating technique with rise times of about 100 ns generally might not be able to resolve the melting plateau of aluminum because they are not sensitive enough for such low temperature ranges. To overcome this obstacle, we constructed a new, fast pyrometer sensitive in this temperature region. Electromagnetic levitation, as the second experimental approach used, delivers data for surface tension (this quantity is not available by means of the pulse-heating technique) and for density of aluminum as a function of temperature. Data obtained will be extensively compared to existing literature data.

  17. Thermophysical properties of lysozyme (protein) solutions

    Science.gov (United States)

    Liu, Jiaching; Yang, Wen-Jei

    1992-01-01

    Thermophysical properties of protein solutions composed of the lysozyme crystals with a 0.1 M sodium acetate and 5 percent NaCl solution as the buffer (pH = 4.0) are determined. The properties being measured include specific heat, thermal conductivity, dynamic viscosity, and surface tension. The protein concentrations are varied. Thermal diffusivity is calculated using the measured results. The purpose of the research is to measure thermophysical properties of lysozyme solutions which would serve as the data bank for controlling and modeling the crystal growth process on earth as well as in space.

  18. THERMOPHYSICAL AND RHEOLOGIC PROPERTIES OF BIOOIL SAMPLES

    Directory of Open Access Journals (Sweden)

    Monika Bozikova

    2013-09-01

    Full Text Available This article deals with thermal properties of selected biooils Plahyd S biooil No1 and Plahyd N biooil No2 and rheologic properties of rapeseed oil. Plahyd S is a synthetic, rapidly biodegradable fluid which is based on sustainable raw materials. It is exceptionally suitable for applications in mobile and stationary hydraulic systems. Plahyd N is multigrade hydraulic oil based on rapeseed oil used in agricultural and construction machinery. For thermal parameters measurements was used Hot wire method. The experiment is based on measuring of the temperature rise vs. time evaluation of an electrically heated wire embedded in the tested material. The thermal conductivity is derived from the resulting change in temperature over a known time interval. Dependency of material resistance against the probe rotation was used at measurement of rheologic properties with instrument viscometer Anton Paar DV 3P. For two samples of biooils Plahyd N and Plahyd S were determined basic thermophysical parameters thermal conductivity, thermal diffusivity and volume specific heat. For each biooil samples were made two series of measurements. In the first series were measured thermal conductivity and thermal diffusivity at constant room temperature 20 C. Every thermophysical parameter was measured 10 times for each sample. The results were statistically processed. For biooil No1 thermal conductivity was 0.325 W*m 1 .K1 , it was higher value than we obtained for biooil No2 0.224 W*m 1 .K 1 . The similar results were obtained for thermal diffusivity of biooil No1 2.140.10 7 m 2 *s 1 and biooil No2 2.604.10 7 m 2* s 1 . For samples with constant temperature were calculated basic statistical characteristics as standard deviation for biooil No1 0.056 W*m 1*K 1 and biooil No2 0.054 W*m 1*K 1; probable error of the arithmetic average for biooil No 1 0.012 W*m 1*K 1 and biooil No 2 0.005 W*m 1*K 1, relative probable error in for biooil No1 3.69 per cent and biooil No2 2

  19. STRUCTURAL AND THERMOPHYSICAL PROPERTIES OF HARDENING CONCRETE

    Directory of Open Access Journals (Sweden)

    L. Krasulina

    2012-01-01

    Full Text Available Structural and thermophysical properties of thermally treated concrete have been studied in the paper. The paper demonstrates regularities of changes in structural and thermophysical properties of concrete during heat treatment process. It is established that stabilization of coefficient values for heat- and temperature conductivity of concrete corresponds to completion of the process pertaining to intensive formation of the material pore structure and indicates the possibility of transition from the stage of isothermal extraction to the stage of temperature decrease. The obtained results are confirmed by studies of strength growth kinetics of concrete samples.

  20. Some research activities on thermophysical properties in China

    Science.gov (United States)

    Zhou, B. L.

    1986-07-01

    Various aspects of the importance of thermophysical property (TPP) studies to science and technology in China are discussed. Several stages of the development of experimental principles and equipment are described. Some examples of TPP applications in economic practice are presented. Theoretical and methodological studies in this field are summarized. The presentations are limited mostly to work on solids.

  1. Investigation of selected thermo-physical properties in the Co-based superalloy: Experiment and application study

    OpenAIRE

    J. Kasala; H. Mäsiar; I. Pernis

    2010-01-01

    Thermo-physical properties are the critical input parameters in computational models of solidification and casting simulations. In thermodynamics, the enthalpy is quotient of thermodynamic potential of a system, which can be used to calculate the useful work obtainable from a closed thermodynamic system under constant pressure. Differential thermal analysis has been used to study melting and solidification paths in the cobalt based superalloy FSX-414. The temperature enthalpy curve was determ...

  2. Thermophysical properties of 1-propylpyridinium tetrafluoroborate

    Energy Technology Data Exchange (ETDEWEB)

    Bandres, Isabel; Lopez, M. Carmen [Departamento de Quimica Fisica, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza (Spain); Castro, Miguel [Instituto de Ciencia de Materiales de Aragon, Universidad de Zaragoza, CSIC, 50009 Zaragoza (Spain); Barbera, Joaquin [Departamento de Quimica Organica, Facultad de Ciencias, ICMA, Universidad de Zaragoza, CSIC, 50009 Zaragoza (Spain); Lafuente, Carlos, E-mail: celadi@unizar.es [Departamento de Quimica Fisica, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza (Spain)

    2012-01-15

    Highlights: > We present a thermophysical characterization of 1-propylpyridinium tetrafluoroborate. > This study includes thermodynamic and transport properties. > Results have been compared with those for 1-butylpyridinium tetrafluoroborate. - Abstract: A systematic thermophysical characterization of the ionic liquid 1-propylpyridinium tetrafluoroborate has been developed. Thus, the density, speed of sound, refractive index, surface tension, viscosity, ionic conductivity, isobaric heat capacity have been determined over the temperature range (278.15 to 338.15) K. Moreover, thermal events have been investigated over the temperature range (120 to 320) K. A comparison between experimental results for the ionic liquid and 1-butylpyridinium tetrafluoroborate studied has been carried out to analyze carefully how the structural modifications in the cation influence the behavior of these compounds.

  3. THERMOPHYSICAL PROPERTIES AND WATER ACTIVITY OF TRANSFERRED CHEESE (UF

    Directory of Open Access Journals (Sweden)

    Mohsen Dalvi Esfahan

    2015-06-01

    Full Text Available Few data are available on the thermophysical properties of cheese in the ripening process.The main objective of this work was to investigate the effects of brining and temperature on the thermophysical properties, i.e., thermal conductivity, specific heat, density and water activity of UF cheese and finally we measure surface heat transfer coefficient .Then we develop models for thermophysical properties based on physical and multiple regression concept .

  4. SIMMER-III analytic thermophysical property model

    International Nuclear Information System (INIS)

    Morita, K; Tobita, Y.; Kondo, Sa.; Fischer, E.A.

    1999-05-01

    An analytic thermophysical property model using general function forms is developed for a reactor safety analysis code, SIMMER-III. The function forms are designed to represent correct behavior of properties of reactor-core materials over wide temperature ranges, especially for the thermal conductivity and the viscosity near the critical point. The most up-to-date and reliable sources for uranium dioxide, mixed-oxide fuel, stainless steel, and sodium available at present are used to determine parameters in the proposed functions. This model is also designed to be consistent with a SIMMER-III model on thermodynamic properties and equations of state for reactor-core materials. (author)

  5. Thermophysical Properties of Fluids and Fluid Mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Sengers, Jan V.; Anisimov, Mikhail A.

    2004-05-03

    The major goal of the project was to study the effect of critical fluctuations on the thermophysical properties and phase behavior of fluids and fluid mixtures. Long-range fluctuations appear because of the presence of critical phase transitions. A global theory of critical fluctuations was developed and applied to represent thermodynamic properties and transport properties of molecular fluids and fluid mixtures. In the second phase of the project, the theory was extended to deal with critical fluctuations in complex fluids such as polymer solutions and electrolyte solutions. The theoretical predictions have been confirmed by computer simulations and by light-scattering experiments. Fluctuations in fluids in nonequilibrium states have also been investigated.

  6. Thermo-Physical Properties of Selected Inconel

    Directory of Open Access Journals (Sweden)

    Krajewski P.K.

    2014-10-01

    Full Text Available The paper brings results of examinations of main thermo-physical properties of selected Inconel alloys, i.e. their heat diffusivity, thermal conductivity and heat capacity, measured in wide temperature range of 20 – 900 oC. Themathematical relationships of the above properties vs. temperature were obtained for the IN 100 and IN 713C alloys. These data can be used when modelling the IN alloys solidification processes aimed at obtaining required structure and properties as well as when designing optimal work temperature parameters.

  7. Thermophysical properties of stainless steels

    International Nuclear Information System (INIS)

    Kim, C.S.

    1975-09-01

    Recommended values of the thermodynamic and transport properties of stainless steels Type 304L and Type 316L are given for temperatures from 300 to 3000 0 K. The properties in the solid region were obtained by extrapolating available experimental data to the melting range, while appropriate correlations were used to estimate the properties in the liquid region. The properties evaluated include the enthalpy, entropy, specific heat, vapor pressure, density, thermal expansion coefficient, thermal conductivity, thermal diffusivity, and viscosity. (9 fig, 11 tables)

  8. Hydrogen technology survey: Thermophysical properties

    Science.gov (United States)

    Mccarty, R. D.

    1975-01-01

    The thermodynamic functions, transport properties, and physical properties of both liquid and gaseous hydrogen are presented. The low temperature regime is emphasized. The tabulation of the properties of normal hydrogen in both Si and engineering units is given along with the tabulation of parahydrogen.

  9. Thermophysical properties of novel zeolite materials for sorption cycles

    KAUST Repository

    Thu, Kyaw

    2013-08-01

    his article discusses the thermophysical properties of zeolite-based adsorbents. Three types of zeolite (Z-01, Z-02 and Z-05) with different chemical compositions developed by Mitsubishi Plastics, Inc. are analyzed for possible applications in adsorption chillers and desalination cycles driven by low-temperature waste heat sources. The experiments are performed using static volumetric method with N2 gas sorption at 77 K. Thermophysical properties such as pore surface area, micropore volume and pore size distribution are evaluated using standard multipoint Brunauer-Emmett-Teller (BET) and Non-Local Density Functional Theory (NLDFT) methods. It is observed that Aluminosilicate functionalized Z-02 exhibits the highest surface area with huge micropore volume. © (2013) Trans Tech Publications, Switzerland.

  10. Stability and thermophysical properties of azithromycin dihydrate

    Directory of Open Access Journals (Sweden)

    S. Timoumi

    2014-04-01

    Full Text Available The aim of this paper was to describe the temperature effect on the stability and the thermophysical properties of azithromycin (AZ. First, the density, the heat capacity and the solubility of original (commercial AZ were determined. Second, the original samples were heated at 50 °C and 80 °C and their PLM, DSC, TGA and XRD data were compared to those of the original AZ. According to our results, the original AZ was a dihydrate which converted to anhydrate when heated up to 80 °C. The dehydration induced a change of crystal habit while the crystalline lattice remained unchanged.

  11. Investigation of selected thermo-physical properties in the Co-based superalloy: Experiment and application study

    Directory of Open Access Journals (Sweden)

    J. Kasala

    2010-01-01

    Full Text Available Thermo-physical properties are the critical input parameters in computational models of solidification and casting simulations. In thermodynamics, the enthalpy is quotient of thermodynamic potential of a system, which can be used to calculate the useful work obtainable from a closed thermodynamic system under constant pressure. Differential thermal analysis has been used to study melting and solidification paths in the cobalt based superalloy FSX-414. The temperature enthalpy curve was determined from differential thermal analysis curves obtained from solidification curves. A solidification simulation of a cobalt base multi-component alloy casting was carried out to predict cooling and shrinkage porosity in the casting of a turbine engine vane segment. The effect of latent heat on the heat transfer calculation was considered by enthalpy method.

  12. Estimation of thermophysical properties in the system Li-Pb

    International Nuclear Information System (INIS)

    Jauch, U.; Schulz, B.

    1986-01-01

    Based on the phase diagram and the knowledge of thermophysical properties data of alloys and intermetallic compounds in the Li-Pb system, quantitative relationships between several properties and between the properties in solid and liquid state are used: to interpret the results on thermophysical properties in the quasibinary system LiPb-Pb and to estimate unknown properties in the concentration range 100 > Li (at.%) > 50. (orig.)

  13. Thermophysical properties of new materials; Proprietes thermophysiques des materiaux nouveaux

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    This conference day was organized by the `thermo-kinetics` section of the French association of thermal engineers. This book of proceedings contains 5 papers entitled: `characterization of thermal properties using periodical methods at the Odeillo test centre: developments and applications`; `measurement of the distribution of local thermophysical properties by IR images processing and averaging technique`; `extension of shock probes to the characterization of multi-layers - development of a simple device for the characterization of insulating materials or shear fluids`; `thermal local diffusivity of constituents of carbon/carbon composites`; `new method for the thermal diffusivity measurement of thermo-hardenable resins during polymerization`. (J.S.)

  14. Characterization of Thermo-Physical Properties of EVA/ATH: Application to Gasification Experiments and Pyrolysis Modeling

    Directory of Open Access Journals (Sweden)

    Bertrand Girardin

    2015-11-01

    Full Text Available The pyrolysis of solid polymeric materials is a complex process that involves both chemical and physical phenomena such as phase transitions, chemical reactions, heat transfer, and mass transport of gaseous components. For modeling purposes, it is important to characterize and to quantify the properties driving those phenomena, especially in the case of flame-retarded materials. In this study, protocols have been developed to characterize the thermal conductivity and the heat capacity of an ethylene-vinyl acetate copolymer (EVA flame retarded with aluminum tri-hydroxide (ATH. These properties were measured for the various species identified across the decomposition of the material. Namely, the thermal conductivity was found to decrease as a function of temperature before decomposition whereas the ceramic residue obtained after the decomposition at the steady state exhibits a thermal conductivity as low as 0.2 W/m/K. The heat capacity of the material was also investigated using both isothermal modulated Differential Scanning Calorimetry (DSC and the standard method (ASTM E1269. It was shown that the final residue exhibits a similar behavior to alumina, which is consistent with the decomposition pathway of EVA/ATH. Besides, the two experimental approaches give similar results over the whole range of temperatures. Moreover, the optical properties before decomposition and the heat capacity of the decomposition gases were also analyzed. Those properties were then used as input data for a pyrolysis model in order to predict gasification experiments. Mass losses of gasification experiments were well predicted, thus validating the characterization of the thermo-physical properties of the material.

  15. Copper Oxide Nanoparticles for Advanced Refrigerant Thermophysical Properties: Mathematical Modeling

    Directory of Open Access Journals (Sweden)

    S. A. Fadhilah

    2014-01-01

    Full Text Available In modern days, refrigeration systems are important for industrial and domestic applications. The systems consume more electricity as compared to other appliances. The refrigeration systems have been investigated thoroughly in many ways to reduce the energy consumption. Hence, nanorefrigerant which is one kind of nanofluids has been introduced as a superior properties refrigerant that increased the heat transfer rate in the refrigeration system. Many types of materials could be used as the nanoparticles to be suspended into the conventional refrigerants. In this study, the effect of the suspended copper oxide (CuO nanoparticles into the 1,1,1,2-tetrafluoroethane, R-134a is investigated by using mathematical modeling. The investigation includes the thermal conductivity, dynamic viscosity, and heat transfer rate of the nanorefrigerant in a tube of evaporator. The results show enhanced thermophysical properties of nanorefrigerant compared to the conventional refrigerant. These advanced thermophysical properties increased the heat transfer rate in the tube. The nanorefrigerant could be a potential working fluid to be used in the refrigeration system to increase the heat transfer characteristics and save the energy usage.

  16. Development of sodium acetate trihydrate-ethylene glycol composite phase change materials with enhanced thermophysical properties for thermal comfort and therapeutic applications.

    Science.gov (United States)

    Kumar, Rohitash; Vyas, Sumita; Kumar, Ravindra; Dixit, Ambesh

    2017-07-12

    The heat packs using phase change materials (PCMs) are designed for possible applications such as body comfort and medical applications under adverse situations. The development and performance of such heat packs rely on thermophysical properties of PCMs such as latent heat, suitable heat releasing temperature, degree of supercooling, effective heat releasing time, crystallite size, stability against spontaneous nucleation in metastable supercooled liquid state and thermal stability during heating and cooling cycles. Such PCMs are rare and the available PCMs do not exhibit such properties simultaneously to meet the desired requirements. The present work reports a facile approach for the design and development of ethylene glycol (EG) and aqueous sodium acetate trihydrate (SAT) based composite phase change materials, showing these properties simultaneously. The addition of 2-3 wt% EG in aqueous SAT enhances the softness of SAT crystallites, its degree of supercooling and most importantly the effective heat releasing time by ~10% with respect to aqueous SAT material. In addition, the maximum heat releasing temperature of aqueous SAT has been tailored from 56.5 °C to 55 °C, 54.9 °C, 53.5 °C, 51.8 °C and 43.2 °C using 2%, 3%, 5%, 7% and 10 wt% EG respectively, making the aqueous SAT-EG composite PCMs suitable for desired thermal applications.

  17. Thermophysical properties of materials for water cooled reactors

    International Nuclear Information System (INIS)

    1997-06-01

    The IAEA Co-ordinated Research Programme (CRP) to establish a thermophysical properties data base for light and heavy water reactor materials was organized within the framework of the IAEA's International Working Group on Advanced Technologies for Water Cooled Reactors. The work within the CRP started in 1990. The objective of the CRP was to collect and systemaize a thermophysical properties data base for light and heavy water reactor materials under normal operating, transient and accident conditions. The important thermophysical properties include thermal conductivity, thermal diffusivity, specific heat capacity, enthalpy, thermal expansion and others. These properties as well as the oxidation of zirconium-based alloys, the thermophysical characteristics of high temperature concrete-core melt interaction and the mechanical properties of construction materials are presented in this report. It is hoped that this report will serve as a useful source of thermophysical properties data for water cooled reactor analyses. The properties data are maintained on the THERSYST system at the University of Stuttgart, Germany and are internationally available. Refs, figs, tabs

  18. Effect of Wood Fillers on the Viscoelastic and Thermophysical Properties of HDPE-Wood Composite

    Directory of Open Access Journals (Sweden)

    M. Tazi

    2016-01-01

    Full Text Available Wood polymer composites (WPC have well proven their applicability in several fields of the plasturgy sector, due to their aesthetics and low maintenance costs. However, for plasturgy applications, the characterization of viscoelastic behavior and thermomechanical and thermophysical properties of WPC with the temperature and wood filler contents is essential. Therefore, the processability of polymer composites made up with different percentage of wood particles needs a better understanding of materials behaviors in accordance with temperature and wood particles contents. To this end, a numerical analysis of the viscoelastic, mechanical, and thermophysical properties of composite composed of high density polyethylene (HDPE reinforced with soft wood particles is evaluated.

  19. Online Data Resources in Chemical Engineering Education: Impact of the Uncertainty Concept for Thermophysical Properties

    Science.gov (United States)

    Kim, Sun Hyung; Kang, Jeong Won; Kroenlein, Kenneth; Magee, Joseph W.; Diky, Vladimir; Muzny, Chris D.; Kazakov, Andrei F.; Chirico, Robert D.; Frenkel, Michael

    2013-01-01

    We review the concept of uncertainty for thermophysical properties and its critical impact for engineering applications in the core courses of chemical engineering education. To facilitate the translation of developments to engineering education, we employ NIST Web Thermo Tables to furnish properties data with their associated expanded…

  20. Thermophysical properties of selected wear-resistant alloys

    International Nuclear Information System (INIS)

    Farwick, D.G.; Johnson, R.N.

    1980-06-01

    Thermophysical properties of 13 selected wear-resistant materials, including specific heat, thermal conductivity, thermal diffusivity, and thermal expansion (instantaneous, mean, and linear) are provided. The Center for Information and Numerical Data Analysis and Synthesis (CINDAS) at Purdue University supplied properties data

  1. Thermophysical properties of supercritical fluids and fluid mixtures

    International Nuclear Information System (INIS)

    Sengers, J.V.

    1989-08-01

    The purpose of the research is to extend the theory of critical phenomena in fluids and fluid mixtures to obtain scientifically based equations that include the crossover from the asymptotic singular behavior of the thermophysical properties close to the critical point to the regular behavior of these properties far away from the critical point

  2. Undercooling Limits and Thermophysical Properties in Glass Forming Alloys

    Science.gov (United States)

    Rhim, Won-Kyu; Ohsaka, Kenichi; Spjut, R. Erik

    1999-01-01

    The primary objective of this program is to produce deeply undercooled metallic liquids and to identify factors that limit undercooling and glass formation. The main research objectives are: (1) Investigating undercooling limits in glass-forming alloys and identifying factors that affect undercooling; (2) Measuring thermophysical properties and investigating the validity of the classical nucleation theory and other existing theories in the extreme undercooled states; and (3) To investigate the limits of electrostatic levitation technology in the ground base and to identify thermophysical parameters that might require reduced-g environment.

  3. Determination of the Thermophysical Properties of Nsukkanut: A ...

    African Journals Online (AJOL)

    The thermophysical properties of 'Nsukkanut', - a CaCl2/CaSO4 absorbent mixture used in solid absorption solar refrigeration [1], were studied in this report. The transient experimental technique of Beck and Al-Araji [12] was used in determining the effective thermal conductivity, specific heat and bulk thermal diffusivity of ...

  4. Nuclear materials thermo-physical property database and property analysis using the database

    International Nuclear Information System (INIS)

    Jeong, Yeong Seok

    2002-02-01

    It is necessary that thermo-physical properties and understand of nuclear materials for evaluation and analysis to steady and accident states of commercial and research reactor. In this study, development of nuclear materials thermo-properties database and home page. In application of this database, it is analyzed of thermal conductivity, heat capacity, enthalpy, and linear thermal expansion of fuel and cladding material and compared thermo-properties model in nuclear fuel performance evaluation codes with experimental data in database. Results of compare thermo-property model of UO 2 fuel and cladding major performance evaluation code, both are similar

  5. Phonon spectrum, mechanical and thermophysical properties of thorium carbide

    Energy Technology Data Exchange (ETDEWEB)

    Pérez Daroca, D., E-mail: pdaroca@tandar.cnea.gov.ar [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica (Argentina); Consejo Nacional de Investigaciones Cientı´ficas y Técnicas (Argentina); Jaroszewicz, S. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica (Argentina); Instituto de Tecnología Jorge A. Sabato, UNSAM-CNEA (Argentina); Llois, A.M. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica (Argentina); Consejo Nacional de Investigaciones Cientı´ficas y Técnicas (Argentina); Mosca, H.O. [Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica (Argentina); Instituto de Tecnología Jorge A. Sabato, UNSAM-CNEA (Argentina)

    2013-06-15

    In this work, we study, by means of density functional perturbation theory and the pseudopotential method, mechanical and thermophysical properties of thorium carbide. These properties are derived from the lattice dynamics in the quasi-harmonic approximation. The phonon spectrum of ThC presented in this article, to the best authors’ knowledge, have not been studied, neither experimentally, nor theoretically. We compare mechanical properties, volume thermal expansion and molar specific capacities with previous results and find a very good agreement.

  6. PHYSICALCHEMICAL CHARACTERIZATION AND THERMOPHYSICAL PROPERTIES OF COCOA HONEY

    Directory of Open Access Journals (Sweden)

    Biano Alves de Melo Neto

    2016-03-01

    Full Text Available The objective of this study was to determine the physicochemical characteristics and thermophysical properties of cocoa hoeny. The cocoa honey had the following physicalchemical characteristics: pH (2.76, titratable acidity (0.73 %, moisture (87,22 %, soluble solids (14,03 °Brix, reducing sugar (10,2 % in glucose, non-reducing sugar (4,06 % in saccharose and ash (0,23 %. With respect to the thermophysical properties were determined the specific heat, density, thermal diffusivity and the dynamic viscosity as a function of temperature. The empirical models for each property were obtained. It was found that the temperature directly affects the cocoa liquor properties. The data are important for the development, adaptation and optimization of equipment for more efficient processing of cocoa honey, since the information on this subject is unknown.

  7. Pure and Pseudo-pure Fluid Thermophysical Property Evaluation and the Open-Source Thermophysical Property Library CoolProp

    DEFF Research Database (Denmark)

    Bell, Ian H.; Wronski, Jorrit; Quoilin, Sylvain

    2014-01-01

    property correlations described here have been implemented into CoolProp, an open-source thermophysical property library. This library is written in C++, with wrappers available for the majority of programming languages and platforms of technical interest. As of publication, 110 pure and pseudo-pure fluids...... are included in the library, as well as properties of 40 incompressible fluids and humid air. The source code for the CoolProp library is included as an electronic annex....

  8. Application of computational thermodynamics to the determination of thermophysical properties as a function of temperature for multicomponent Al-based alloys

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Fabiana C. [Fluminense Federal University, Graduate Program in Metallurgical Engineering, Av. dos Trabalhadores, 420-27255-125 Volta Redonda, RJ (Brazil); Paresque, Mara C.C. [Fluminense Federal University, Graduate Program in Mechanical Engineering, Av. dos Trabalhadores, 420-27255-125 Volta Redonda, RJ (Brazil); Castro, José A. de [Fluminense Federal University, Graduate Program in Metallurgical Engineering, Av. dos Trabalhadores, 420-27255-125 Volta Redonda, RJ (Brazil); Jácome, Paulo A.D. [Fluminense Federal University, Graduate Program in Mechanical Engineering, Av. dos Trabalhadores, 420-27255-125 Volta Redonda, RJ (Brazil); Garcia, Amauri, E-mail: amaurig@fem.unicamp.br [University of Campinas – UNICAMP, Department of Manufacturing and Materials Engineering, 13083-860 Campinas, SP (Brazil); Ferreira, Ivaldo L. [Fluminense Federal University, Graduate Program in Mechanical Engineering, Av. dos Trabalhadores, 420-27255-125 Volta Redonda, RJ (Brazil)

    2015-11-10

    Highlights: • A model coupled to a computational thermodynamics software is proposed to compute thermophysical properties. • The model applies to multicomponent alloys and has been validated against experimental results. • Density and specific heat as a function of temperature are computed for Al–Si–Cu alloys. - Abstract: Despite the technological importance of Al–Si–Cu alloys in manufacturing processes involving heat transfer, such as welding, casting and heat treatment, thermophysical properties of this system of alloys are very scarce in the literature. In this paper, a model connected to a computational thermodynamics software is proposed permitting density and specific heats as a function of temperature and enthalpy of transformations to be numerically determined. The model is pre-validated against experimental density as a function of temperature for liquid and solid phases of A319 and 7075 alloys found in the literature and validated against experimental density values for the solid phase of an Al-6 wt%Cu-1 wt%Si alloy determined in the present study. In both cases the numerical predictions are in good agreement with the experimental results. Specific heat and temperatures and heats of transformation are also numerically determined for this ternary Al-based alloy.

  9. Thermophysical and Thermomechanical Properties of Thermal Barrier Coating Systems

    Science.gov (United States)

    Zhu, Dongming; Miller, Robert A.

    2000-01-01

    Thermal barrier coatings have been developed for advanced gas turbine and diesel engine applications to improve engine reliability and fuel efficiency. However, the issue of coating durability under high temperature cyclic conditions is still of major concern. The coating failure is closely related to thermal stresses and oxidation in the coating systems. Coating shrinkage cracking resulting from ceramic sintering and creep at high temperatures can further accelerate the coating failure process. The purpose of this paper is to address critical issues such as ceramic sintering and creep, thermal fatigue and their relevance to coating life prediction. Novel test approaches have been established to obtain critical thermophysical and thermomechanical properties of the coating systems under near-realistic temperature and stress gradients encountered in advanced engine systems. Emphasis is placed on the dynamic changes of the coating thermal conductivity and elastic modulus, fatigue and creep interactions, and resulting failure mechanisms during the simulated engine tests. Detailed experimental and modeling results describing processes occurring in the thermal barrier coating systems provide a framework for developing strategies to manage ceramic coating architecture, microstructure and properties.

  10. Prediction of thermo-physical properties of liquid formulated products

    DEFF Research Database (Denmark)

    Mattei, Michele; Conte, Elisa; Kontogeorgis, Georgios

    2013-01-01

    The objective of this chapter is to give an overview of the models, methods and tools that may be used for the estimation of liquid formulated products. First a classification of the products is given and the thermo-physical properties needed to represent their functions are listed. For each...... property, a collection of the available models are presented according to the property type and the model type. It should be noted, however, that the property models considered or highlighted in this chapter are only examples and are not necessarily the best and most accurate for the corresponding property....

  11. Morphology and thermophysical properties of non-aqueous titania nanofluids

    Science.gov (United States)

    Murshed, S. M. S.; Santos, F. J. V.; Nieto de Castro, C. A.; Patil, V. S.; Patil, K. R.

    2018-02-01

    This work deals with the experimental investigation on thermophysical properties of TiO2-nanofluids and characterization of morphology and structure of TiO2 nanoparticles. Non-aqueous liquids like silicone oil and ethylene glycol are used as base fluids to prepare the nanofluids. Thermophysical properties including viscosity and thermal conductivity of these nanofluids are measured at different concentrations and temperatures. Results showed that silicone oil-based TiO2 nanofluid is Newtonian and the viscosity of this nanofluid increases with the loading of nanoparticles but it decreases nonlinearly with increasing temperature. Existing viscosity models are found unable to predict the viscosity of nanofluids. Although the effective thermal conductivities of both the silicone oil and ethylene glycol-based nanofluids increased with the TiO2 concentration, their enhanced thermal conductivity was found to decrease with increasing temperature.

  12. Data mining techniques for thermophysical properties of refrigerants

    International Nuclear Information System (INIS)

    Kuecueksille, Ecir Ugur; Selbas, Resat; Sencan, Arzu

    2009-01-01

    This study presents ten modeling techniques within data mining process for the prediction of thermophysical properties of refrigerants (R134a, R404a, R407c and R410a). These are linear regression (LR), multi layer perception (MLP), pace regression (PR), simple linear regression (SLR), sequential minimal optimization (SMO), KStar, additive regression (AR), M5 model tree, decision table (DT), M5'Rules models. Relations depending on temperature and pressure were carried out for the determination of thermophysical properties as the specific heat capacity, viscosity, heat conduction coefficient, density of the refrigerants. Obtained model results for every refrigerant were compared and the best model was investigated. Results indicate that use of derived formulations from these techniques will facilitate design and optimize of heat exchangers which is component of especially vapor compression refrigeration system

  13. Mechanical and thermophysical properties of hot-pressed SYNROC B

    International Nuclear Information System (INIS)

    Hoenig, C.L.; Newkirk, H.W.; Otto, R.A.; Brady, R.L.; Brown, A.E.; Ulrich, A.R.; Lum, R.C.

    1981-01-01

    The optimal SYNROC compositons for use with commercial waste are reviewed. Large amounts of powder (about 2.5 kg) were prepared by convention al ceramic operations to test the SYNROC concept on a processing scale. Samples, 15.2 cm in diameter, were hot pressed in graphite, and representative samples were cut for microstructural evaluations. Measured mechanical and thermophysical properties did not vary significantly as a function of sample location and were typical of titanate ceramic materials

  14. Investigation of thermophysical properties of nanofluids

    International Nuclear Information System (INIS)

    Vieira, Tiago A.S.; Vidal, Guilherme A.M.; Macedo, Gleydson A.; Santos, André A.C. dos; Silva Junior, Geraldo E.

    2017-01-01

    In the present study the thermal conductivities and viscosities of some nanofluids were evaluated. Four water-based nanofluids containing solid particulates were studied. The solid particulates used were titanium oxide (TiO 2 ), aluminum oxide (Al 2 O 3 ), iron oxide (Fe 3 O 4 ) and graphene. For this evaluation, we used experimental values available in journals and values calculated by theoretical models. For thermal conductivity theoretical models used were Maxwell, Hamilton and Crosser, Shukla and Dhir, Yu and Choi, Patel and Murshed; for viscosity the theoretical models used were Einstein, Brinkman, Batchelor, Krigger and Dowgherty, Kulkarni and Nielsen. The effects of nanoparticle concentration and temperature on the properties of fluids were raised. Four volume concentrations were used for each fluid. The concentrations used were different for each fluid, according to availability in the literature. Comparisons were made between the theoretical models for the chosen properties with their experimental values. The comparisons between models and experiments were made with the intention of selecting the best model to predict the chosen properties values and, consequently, to evaluate potential applications in the area of nuclear reactors

  15. Optical Fier Based System for Multiple Thermophysical Properties for Glove Box, Hot Cell and In-Pile Application

    Energy Technology Data Exchange (ETDEWEB)

    Ban, Heng

    2017-11-30

    Thermal diffusivity of materials is of interest in nuclear applications at temperatures in excess of 2000°C. Commercial laser flash apparatus (LFA) that heats samples with a furnace typically do not reach these elevated temperatures nor are they easily adapted to a glove-box or hot cell environment. In this research, we performed work on an experimental technique using single laser surface heating, i.e. heating the disk sample only at its front surface with the continuous wave (CW) laser, to allow measurement of thermal diffusivity at very high temperatures within a small chamber. Thermal diffusivity is measured using a separate pulsed laser on the front side and IR detector on the rear side. The new way of heating provides easy operation in comparison to other heating methods. The measurement of sample reference temperature is needed for the measured thermal diffusivity. A theoretical model was developed to describe transient heat transfer across the sample due to the laser pulse, starting from the steady state temperature of the sample heated by the CW laser. The experimental setup was established with a 500W CW laser and maximum 50 Joule pulse laser irradiated at the front surface of the sample. The induced temperature rise at the rear surface, along with the steady-state temperature at the front surface, was recorded for the determination of thermal diffusivity and the sample temperature. Three samples were tested in vacuum over a wide temperature range of 500°C to 2100°C, including graphite, Inconel 600 and tungsten. The latter two samples were coated with sprayed graphite on their front surfaces in order to achieve surface absorption/emission needs, i.e. high absorptivity of the front surface against relatively low emissivity of the rear surface. Thermal diffusivity of graphite determined by our system are within a 5% difference of the commercial LFA data at temperatures below 1300°C and agree well with its trend at higher temperatures. Good agreement

  16. Thermophysical properties of supercritical fluids and fluid mixtures

    International Nuclear Information System (INIS)

    Sengers, J.V.

    1991-07-01

    This research is concerned with the development of a quantitative scientific description of the thermodynamic and transport properties of supercritical and subcritical fluids and fluid mixtures. It is known that the thermophysical properties of fluids and fluid mixtures asymptotically close to the critical point satisfy scaling laws with universal critical exponents and universal scaling functions. However, the range of validity of these asymptotic scaling laws is quite small. As a consequence, the impact of the modern theory of critical phenomena on chemical engineering has been limited. On the other hand, an a priori estimate of the range of temperatures and densities, where critical fluctuations become significant, can be made on the basis of the so-called Ginzburg criterion. A recent analysis of this criterion suggests that this range is actually quite large and for a fluid like carbon dioxide can easily extend to 100 degrees or so above the critical temperature. Hence, the use of traditional engineering equations like cubic equations is not scientifically justified in a very wide range of temperatures and densities around the critical point. We have therefore embarked on a scientific approach to deal with the global effects of critical fluctuations on the thermophysical properties of fluids and fluid mixtures. For this purpose it is not sufficient to consider the asymptotic critical fluctuations but we need to deal also with the nonasymptotic critical fluctuations. The goal is to develop scientifically based questions that account for the crossover of the thermophysical properties from their asymptotic singular behavior in the near vicinity of the critical point to their regular behavior very far away from the critical point

  17. Thermophysical properties of uranium dioxide - Version 0 for peer review

    International Nuclear Information System (INIS)

    Fink, J.K.; Petri, M.C.

    1997-02-01

    Data on thermophysical properties of solid and liquid UO 2 have been reviewed and critically assessed to obtain consistent thermophysical property recommendations for inclusion in the International Nuclear Safety Center Database on the World Wide Web (http://www.insc.anl.gov.). Thermodynamic properties that have been assessed are enthalpy, heat capacity, melting point, enthalpy of fusion, thermal expansion, density, surface tension, and vapor pressure. Transport properties that have been assessed are thermal conductivity, thermal diffusivity, viscosity, and emissivity. Summaries of the recommendations with uncertainties and detailed assessments for each property are included in this report and in the International Nuclear Safety Center Database for peer review. The assessments includes a review of the experiments and data, an examination of previous recommendations, the basis for selecting recommendations, a determination of uncertainties, and a comparison of recommendations with data and with previous recommendations. New data and research that have led to new recommendations include thermal expansion and density measurements of solid and liquid UO 2 , derivation of physically-based equations for the thermal conductivity of solid UO 2 , measurements of the heat capacity of liquid UO 2 , and measurements and analysis of the thermal conductivity of liquid UO 2

  18. Thermophysical properties of uranium dioxide - Version 0 for peer review

    Energy Technology Data Exchange (ETDEWEB)

    Fink, J.K.; Petri, M.C.

    1997-02-01

    Data on thermophysical properties of solid and liquid UO{sub 2} have been reviewed and critically assessed to obtain consistent thermophysical property recommendations for inclusion in the International Nuclear Safety Center Database on the World Wide Web (http://www.insc.anl.gov.). Thermodynamic properties that have been assessed are enthalpy, heat capacity, melting point, enthalpy of fusion, thermal expansion, density, surface tension, and vapor pressure. Transport properties that have been assessed are thermal conductivity, thermal diffusivity, viscosity, and emissivity. Summaries of the recommendations with uncertainties and detailed assessments for each property are included in this report and in the International Nuclear Safety Center Database for peer review. The assessments includes a review of the experiments and data, an examination of previous recommendations, the basis for selecting recommendations, a determination of uncertainties, and a comparison of recommendations with data and with previous recommendations. New data and research that have led to new recommendations include thermal expansion and density measurements of solid and liquid UO{sub 2}, derivation of physically-based equations for the thermal conductivity of solid UO{sub 2}, measurements of the heat capacity of liquid UO{sub 2}, and measurements and analysis of the thermal conductivity of liquid UO{sub 2}.

  19. Thermophysical property characterization of tris(hydroxymethyl)aminomethane

    International Nuclear Information System (INIS)

    Soriano, Allan N.; Cabahug, Denise Irene V.; Li Menghui

    2011-01-01

    In this present work, a thermophysical property characterization of aqueous solution of tris(hydroxymethyl)aminomethane (TRIS), a biological buffer, was done. The investigated properties were refractive index (n), density (ρ), and electrolytic conductivity (κ). These properties were measured for temperatures up to 353.15 K (at normal atmospheric condition) and for the entire composition range where TRIS is still soluble in water. The measured properties were reported as functions of temperature and composition. A modified form of the Vogel-Tamman-Fulcher equation which leads to an Arrhenius-type asymptotic exponential function was used to generally correlate the temperature and compositional dependence of the considered properties and satisfactory results were obtained.

  20. Thermophysical properties of reconsolidating crushed salt.

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Stephen J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Urquhart, Alexander [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-03-01

    Reconsolidated crushed salt is being considered as a backfilling material placed upon nuclear waste within a salt repository environment. In-depth knowledge of thermal and mechanical properties of the crushed salt as it reconsolidates is critical to thermal/mechanical modeling of the reconsolidation process. An experimental study was completed to quantitatively evaluate the thermal conductivity of reconsolidated crushed salt as a function of porosity and temperature. The crushed salt for this study came from the Waste Isolation Pilot Plant (WIPP). In this work the thermal conductivity of crushed salt with porosity ranging from 1% to 40% was determined from room temperature up to 300°C, using two different experimental methods. Thermal properties (including thermal conductivity, thermal diffusivity and specific heat) of single-crystal salt were determined for the same temperature range. The salt was observed to dewater during heating; weight loss from the dewatering was quantified. The thermal conductivity of reconsolidated crushed salt decreases with increasing porosity; conversely, thermal conductivity increases as the salt consolidates. The thermal conductivity of reconsolidated crushed salt for a given porosity decreases with increasing temperature. A simple mixture theory model is presented to predict and compare to the data developed in this study.

  1. COST 507: Thermophysical properties of light metal alloys. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Jaroma-Weiland, G.; Brandt, R.; Neuer, G.

    1994-02-15

    The thermophysical properties of Al-, Mg- and Ti-based light metal alloys have been studied by reviewing the literature published so far, evaluating the empirical results and by empirical investigations. The properties to the covered in the literature research are: thermal conductivity, thermal diffusivity, specific heat capacity, thermal expansion and electrical resistivity. The data have been stored in the factual data base THERSYST together with the results of experimental measurements supplied from participants of the COST 507-action (Group D). Altogether 1325 data-sets referring to 146 alloys have been stored. They have been uniformly represented and critically analyzed by means of the THERSYST program moduli. These numerical data cover a number of systems with variing chemical composition and thermal treatment. Partly large discrepancies especially of the thermal conductivity have been found for similar alloys. The problem of experimental uncertainities has been studied in detail by investigation of AA-8090 alloy (Al-2.5Li-1.1Cu). The thermophysical properties of monolithic alloy KS1275 (AlSi12CuNi) and metal matrix composite (KS1275 reinforced with Al2O3 short fibre) have been determined experimentally. (orig.)

  2. Thermophysical Properties of Heat Resistant Shielding Material

    International Nuclear Information System (INIS)

    Porter, W.D.

    2004-01-01

    This project was aimed at determining thermal conductivity, specific heat and thermal expansion of a heat resistant shielding material for neutron absorption applications. These data are critical in predicting the structural integrity of the shielding under thermal cycling and mechanical load. The measurements of thermal conductivity and specific heat were conducted in air at five different temperatures (-31 F, 73.4 F, 140 F, 212 F and 302 F). The transient plane source (TPS) method was used in the tests. Thermal expansion tests were conducted using push rod dilatometry over the continuous range from -40 F (-40 C) to 302 F (150 C)

  3. Uranium tetrafluoride thermophysical properties measurements by the laser flash method

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira Neto, Ricardo Alberto; Camarano, Denise das Merces; Miranda, Odair; Grossi, Pablo Andrade; Carneiro, Luciana Capanema Silva; Silva, Egonn Hendrigo Carvalho; Migliorini, Fabricio Lima, E-mail: ranf@cdtn.br, E-mail: dmc@cdtn.br, E-mail: odairm@cdtn.br, E-mail: pabloag@cdtn.br, E-mail: lucsc@hotmail.com, E-mail: egonn@ufmg.br, E-mail: flmigliorini@gmail.com [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte - MG (Brazil); Aguiar, Bruno Moreira de; Borges, Wesden de Almeida; Saliba-Silva, Adonis Marcelo, E-mail: bruaguiar@ipen.br, E-mail: wesden@hotmail.com, E-mail: saliba@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    In order to increase the efficiency of the metalothermic reduction process employed by the IPEN - Instituto de Pesquisas Energeticas e Nucleares, to produce metallic uranium by means of uranium tetrafluoride reduction with magnesium, is planned utilize a mathematical model that numerically simulates the heat distribution in the charge of powders of uranium tetrafluoride and metallic magnesium duly blended. Because this program requires as input data the thermal conductivity of the uranium tetrafluoride powder and this data was not found in the literature, pellets were produced by uniaxially pressing the uranium tetrafluoride powder in pellets, employing the same technology developed at CDTN-Centro de Desenvolvimento da Tecnologia Nuclear, to produce nuclear fuel pellets. The thermophysical properties of these pellets were measured at the LMPT - Laboratorio de Medicao de Propriedades Termofisicas de Combustiveis Nucleares e Materiais of CDTN applying the laser flash method. From the measurements results, it was possible to obtain an extrapolated value of ca. 0.24 W.m{sup -1}.K{sup -1} for the thermal conductivity of the UF{sub 4} powder sample in the loose state and at room temperature. This value will be employed as input data of the mathematical model, whose results will be subject of a future publication. The UF{sub 4} powder pelletizing parameters and the thermophysical properties results (density, thermal diffusivity and thermal conductivity), are reported. (author)

  4. Thermophysical properties of fluids: dynamic viscosity and thermal conductivity

    Science.gov (United States)

    Latini, G.

    2017-11-01

    Thermophysical properties of fluids strongly depend upon atomic and molecular structure, complex systems governed by physics laws providing the time evolution. Theoretically the knowledge of the initial position and velocity of each atom, of the interaction forces and of the boundary conditions, leads to the solution; actually this approach contains too many variables and it is generally impossible to obtain an acceptable solution. In many cases it is only possible to calculate or to measure some macroscopic properties of fluids (pressure, temperature, molar volume, heat capacities...). The ideal gas “law,” PV = nRT, was one of the first important correlations of properties and the deviations from this law for real gases were usefully proposed. Moreover the statistical mechanics leads for example to the “hard-sphere” model providing the link between the transport properties and the molecular size and speed of the molecules. Further approximations take into account the intermolecular interactions (the potential functions) which can be used to describe attractions and repulsions. In any case thermodynamics reduces experimental or theoretical efforts by relating one physical property to another: the Clausius-Clapeyron equation provides a classical example of this method and the PVT function must be known accurately. However, in spite of the useful developments in molecular theory and computers technology, often it is usual to search for physical properties when the existing theories are not reliable and experimental data are not available: the required value of the physical or thermophysical property must be estimated or predicted (very often estimation and prediction are improperly used as synonymous). In some cases empirical correlations are useful, if it is clearly defined the range of conditions on which they are based. This work is concerned with dynamic viscosity µ and thermal conductivity λ and is based on clear and important rules to be respected

  5. Thermoplastic Polyurethane Elastomer Nanocomposites: Morphology, Thermophysical, and Flammability Properties

    Directory of Open Access Journals (Sweden)

    Wai K. Ho

    2010-01-01

    Full Text Available Novel materials based on nanotechnology creating nontraditional ablators are rapidly changing the technology base for thermal protection systems. Formulations with the addition of nanoclays and carbon nanofibers in a neat thermoplastic polyurethane elastomer (TPU were melt-compounded using twin-screw extrusion. The TPU nanocomposites (TPUNs are proposed to replace Kevlar-filled ethylene-propylene-diene-monomer rubber, the current state-of-the-art solid rocket motor internal insulation. Scanning electron microscopy analysis was conducted to study the char characteristics of the TPUNs at elevated temperatures. Specimens were examined to analyze the morphological microstructure during the pyrolysis reaction and in fully charred states. Thermophysical properties of density, specific heat capacity, thermal diffusivity, and thermal conductivity of the different TPUN compositions were determined. To identify dual usage of these novel materials, cone calorimetry was employed to study the flammability properties of these TPUNs.

  6. Thermophysical Properties of ZrB2-Based Ceramics

    International Nuclear Information System (INIS)

    Zimmermann, James W.; Hilmas, Gregory E.; Fahrenholtz, William G.; Buchheit, Andrew A; Dinwiddie, Ralph Barton; Porter, Wallace D; Wang, Hsin

    2008-01-01

    Thermophysical properties were investigated for ZrB2 and ZrB2-30vol% SiC ceramics. Thermal conductivities were calculated from measured thermal diffusivities, heat capacities, and thermal expansions. The thermal conductivity of ZrB2 increased from 58.7 W/m K at room temperature to 62.0 W/m K at 1675 K, whereas the thermal conductivity of ZrB2-SiC decreased from 62.0 W/m K to 56 W/m K over the same temperature range. Electron and phonon contributions to thermal conductivity were determined using electrical resistivity measurements and were used, along with grain size models, to explain the observed trends. The results are compared to previously reported thermal conductivities for ZrB2 and ZrB2-SiC

  7. Nanomodified polymer composites: Thermophysical and physico-mechanical properties

    Science.gov (United States)

    Shchegolkov, Alexander; Shchegolkov, Alexey; Dyachkova, Tatyana; Borovskikh, Pavel

    2017-11-01

    The paper presents the results of investigation of thermophysical and physicomechanical properties of polymer-based composites modified with paraffin and carbon nanotubes (CNTs) mixture. Thermal conductivity of composites based on polyethylene, fluoroplastic, polyvinyl chloride (PVC) is 0.48, 0.42 and 0.36 W/(m.°C), respectively, compared to thermal conductivity of pure paraffin - 0.25 W/(m.°C). It has been revealed that for materials heat capacity the polymer matrix determines the position of the maximum point on temperature dependence having extreme nature. Temperature changes in composites volume do not exceed 3% from the initial state to the phase transition, that allows them to be used in a combination with other materials.

  8. Thermophysical properties and some parameters of liquid sodium

    International Nuclear Information System (INIS)

    Rapeanu, S.; Padureanu, I.; Rotarescu, G.; Craciun, C.; Ion, M.

    1982-07-01

    In the paper are reported some results on the thermophysical properties of the liquid sodium obtained by means of the neutron scattering and of the theories existing for various physical parameters. The results are based on hard sphere approach and neutron diffraction experiments performed in the region of the small momentum transfer. From this measurement extrapolated at Q → 0, the packing fraction eta as a function of temperature in the range 100-600 deg is obtained. Knowing the parameter eta, the structure factor S(Q) and the radial distribution function g(r) are calculated. To calculate various physical parameters of the liquid sodium like: electrical resistivity, thermoelectric power, viscosity coefficient, electrical conductivity etc., S(Q), g(r) and a Lennard Jones interaction potential phi(r) are used. (authors)

  9. Report of the consultancy on review of thermophysical properties of materials for advanced water-cooled reactors. Working material

    International Nuclear Information System (INIS)

    1996-01-01

    Since 1990 the IAEA's Nuclear Power Technology Development Section has carried out a coordinated research programme on thermophysical properties of materials for advanced water cooled reactors. The objective of this activity has been to collect and systematize a thermophysical properties data base for light and heavy water reactor materials under normal operating and transient conditions. This activity has been organized within the frame of IAEA's International Working Group on Advanced Technologies for Water-cooled Reactors. The important thermophysical properties include thermal conductivity, thermal diffusivity, specific heat capacity, enthalpy, thermal expansion and others. Several organizations involved in this CRP have suggested establishment of a new programme to extend the database to include properties in the liquid region applicable to severe accidents, to critically assess and peer review the property data and correlations, and to recommend the most appropriate data. The purpose of the consultancy was to examine the interest in further cooperation, and, if appropriate, to prepare the scope and approach for a potential new international collaborative programme to collect and review thermophysical properties data for advanced water cooled reactors and to recommend the most appropriate data. Figs

  10. Measuring the Thermophysical and Structural Properties of Glass-Forming and Quasicrystal-Forming Liquids

    Science.gov (United States)

    Hyers, Robert W.; Bradshaw, Richard C.; Rogers, Jan R.; Gangopadhyay, Anup K.; Kelton, Ken F.

    2006-01-01

    The thermophysical properties of glass-forming and quasicrystal-forming alloys show many interesting features in the undercooled liquid range. Some of the features in the thermophysical property curves are expected to reflect changes in the structure and coordination of the liquid. These measurements require containerless processing such as electrostatic levitation to access the undercooled liquid regime. An overview of the state of the art in measuring the thermophysical properties and structure of undercooled liquid glass-forming and quasicrystal-forming alloys will be presented, along with the status of current measurements.

  11. Thermophysical properties of enzyme clarified Lime (Citrus aurantifolia L) juice at different moisture contents.

    Science.gov (United States)

    Manjunatha, S S; Raju, P S; Bawa, A S

    2014-11-01

    Thermophysical properties of enzyme clarified lime (Citrus aurantifolia L.) juice were evaluated at different moisture contents ranging from 30.37 % to 89.30 % (wet basis) corresponding to a water activity range of 0.835 to 0.979. The thermophysical properties evaluated were density, Newtonian viscosity, thermal conductivity, specific heat and thermal diffusivity. The investigation showed that density and Newtonian viscosity of enzyme clarified lime juice decreased significantly (p thermal conductivity and specific heat increased significantly (p thermal diffusivity increased marginally. Empirical mathematical models were established relating to thermophysical properties of enzyme clarified lime juice with moisture content/water activity employing regression analysis by the method of least square approximation. Results indicated the existence of strong correlation between thermophysical properties and moisture content/water activity of enzyme clarified lime juice, a significant (p thermal properties was observed.

  12. Thermophysical Properties of Liquid Te: Density, Electrical Conductivity, and Viscosity

    Science.gov (United States)

    Li, C.; Su, C.; Lehoczky, S. L.; Scripa, R. N.; Ban, H.; Lin, B.

    2004-01-01

    The thermophysical properties of liquid Te, namely, density, electrical conductivity, and viscosity, were determined using the pycnometric and transient torque methods from the melting point of Te (723 K) to approximately 1150 K. A maximum was observed in the density of liquid Te as the temperature was increased. The electrical conductivity of liquid Te increased to a constant value of 2.89 x 10(exp 5 OMEGA-1m-1) as the temperature was raised above 1000 K. The viscosity decreased rapidly upon heating the liquid to elevated temperatures. The anomalous behaviors of the measured properties are explained as caused by the structural transitions in the liquid and discussed in terms of Eyring's and Bachiskii's predicted behaviors for homogeneous liquids. The Properties were also measured as a function of time after the liquid was coded from approximately 1173 or 1123 to 823 K. No relaxation phenomena were observed in the properties after the temperature of liquid Te was decreased to 823 K, in contrast to the relaxation behavior observed for some of the Te compounds.

  13. Molecular dynamics simulation of thermophysical properties of undercooled liquid cobalt

    International Nuclear Information System (INIS)

    Han, X J; Wang, J Z; Chen, M; Guo, Z Y

    2004-01-01

    Molecular dynamics simulations with two different embedded-atom-method (EAM) potentials are applied to calculate the density, specific heat and self-diffusion coefficient of liquid cobalt at temperatures above and below the melting temperature. Simulation shows that Pasianot's EAM model of cobalt constructed on the basis of a hcp structure is more successful than Stoop's EAM model in the framework of a fcc structure in predicting the thermophysical properties of liquid cobalt. Simulations with Pasianot's EAM model indicate that the density fits into ρ = 7.49-9.17 x 10 -4 (T- T m ) g cm -3 , and the self-diffusion coefficient is given by D = 1.291 x 10 -7 exp(-48 795.71/RT) m 2 s -1 . Dissimilar to the linear dependence of the density and the Arrhenius dependence of the self-diffusion coefficient on temperature, the specific heat shows almost a constant value of 38.595 ± 0.084 J mol -1 K -1 within the temperature range of simulation. The simulated properties of liquid cobalt are compared with experimental data available. Comparisons show reasonable agreements between the simulated results from Pasianot's EAM model and experimental data

  14. Thermophysical properties of hydrophobised lime plasters - The influence of ageing

    Science.gov (United States)

    Pavlíková, Milena; Zemanová, Lucie; Pavlík, Zbyšek

    2017-07-01

    The building envelope is a principal responsible for buildings energy loses. Lime plasters as the most popular finishing materials of historical buildings and culture monuments influence the thermal behaviour as well as construction material of masonry. On this account, the effect of ageing on the thermophysical properties of a newly designed lime plasters containing hydrophobic admixture is analysed in the paper. For the comparative purposes, the reference lime plaster is tested. The ageing is accelerated with controlled carbonation process to simulate the final plasters properties. Basic characterization of the tested materials is done using bulk density, matrix density, and porosity measurements. Thermal conductivity and volumetric heat capacity are experimentally assessed using a transient impulse method. The obtained data revealed the significant changes of the both studied thermal parameters in the dependence on plasters composition and age. The assessed material parameters will be stored in a material database, where will find use as an input data for computational modelling of heat transport in this type of porous building materials and evaluation of energy-savings and sustainability issues.

  15. Thermophysical properties of 1-butyl-4-methylpyridinium tetrafluoroborate

    International Nuclear Information System (INIS)

    Safarov, Javid; Kul, Ismail; El-Awady, Waleed A.; Nocke, Jürgen; Shahverdiyev, Astan; Hassel, Egon

    2012-01-01

    Highlights: ► (p, ρ, T) data of 1-butyl-4-methylpyridinium tetrafluoroborate are estimated. ► The measurements were carried out with a vibration-tube densimeter. ► The thermomechanical coefficients were calculated. - Abstract: Thermophysical properties, {(p, ρ, T) at T = (283.15 to 393.15) K, pressures up to p = 100 MPa, and viscosity at T = (283.15 to 373.15) K and p = 0.101 MPa}, of 1-butyl-4-methylpyridinium tetrafluoroborate [b4mpy][BF 4 ] are reported. The measurements were carried out with a recently constructed Anton-Paar DMA HPM vibration-tube densimeter and a fully automated SVM 3000 Anton-Paar rotational Stabinger viscometer. The vibration-tube densimeter was calibrated using double-distilled water, methanol, toluene, and aqueous NaCl solutions. An empirical equation of state for fitting of the (p, ρ, T) data of [b4mpy][BF 4 ] has been developed as a function of pressure and temperature to calculate the thermal properties of the ionic liquid (IL), such as isothermal compressibility, isobaric thermal expansibility, differences in isobaric and isochoric heat capacities, thermal pressure coefficient, and internal pressure. Internal pressure and the temperature coefficient of internal pressure data were used to make conclusions on the molecular characteristics of the IL.

  16. Thermophysical properties of ammonium and hydroxylammonium protic ionic liquids

    International Nuclear Information System (INIS)

    Chhotaray, Pratap K.; Gardas, Ramesh L.

    2014-01-01

    Highlights: • Density, viscosity and sound velocity measured for five ammonium and hydroxylammonium based protic ionic liquids. • Experimental density and viscosity data estimated using Gardas and Coutinho model and Vogel–Tamman–Fulcher equation. • Effects of cation, anion and alkyl chain length on studied properties have been discussed. • The intermolecular interactions were analyzed on the basis of derived properties. - Abstract: In this work, five protic ionic liquids having propylammonium, 3-hydroxy propylammonium as cations and formate, acetate, trifluoroacetate as anions have been synthesized. Thermophysical properties such as density (ρ), viscosity (η) and sound velocity (u) have been measured at various temperatures ranging from (293.15 to 343.15) K at atmospheric pressure. The experimental density and viscosity were fitted with second order polynomial and Vogel–Tamman–Fulcher (VTF) equations, respectively. Also experimental densities were correlated with the estimated density proposed by Gardas and Coutinho model. The coefficient of thermal expansion (α) and isentropic compressibility (β s ) values have been calculated from the experimental density and sound velocity data using empirical correlations. Lattice potential energy (U POT ) has been calculated to understand the strength of ionic interaction between the ions. Thermal decomposition temperature (T d ) and glass transition temperature (T g ) along with crystallization and melting point were investigated using TGA and DSC analysis, respectively. The effect of alkyl chain length and electronegative fluorine atoms on anionic fragment as well as hydroxyl substituent on cationic side chain in the protic ionic liquids has been discussed for studied properties. The effect of ΔpK a over the studied properties has also been analyzed

  17. Thermophysical properties study of micro/nanoscale materials

    Science.gov (United States)

    Feng, Xuhui

    Thermal transport in low-dimensional structure has attracted tremendous attentions because micro/nanoscale materials play crucial roles in advancing micro/nanoelectronics industry. The thermal properties are essential for understanding of the energy conversion and thermal management. To better investigate micro/nanoscale materials and characterize the thermal transport, pulse laser-assisted thermal relaxation 2 (PLTR2) and transient electrothermal (TET) are both employed to determine thermal property of various forms of materials, including thin films and nanowires. As conducting polymer, Poly(3-hexylthiophene) (P3HT) thin film is studied to understand its thermal properties variation with P3HT weight percentage. 4 P3HT solutions of different weight percentages are compounded to fabricate thin films using spin-coating technique. Experimental results indicate that weight percentage exhibits impact on thermophysical properties. When percentage changes from 2% to 7%, thermal conductivity varies from 1.29 to 1.67 W/m·K and thermal diffusivity decreases from 10-6 to 5×10-7 m2/s. Moreover, PLTR2 technique is applied to characterize the three-dimensional anisotropic thermal properties in spin-coated P3HT thin films. Raman spectra verify that the thin films embrace partially orientated P3HT molecular chains, leading to anisotropic thermal transport. Among all three directions, lowest thermal property is observed along out-of-plane direction. For in-plane characterization, anisotropic ratio is around 2 to 3, indicating that the orientation of the molecular chains has strong impact on the thermal transport along different directions. Titanium dioxide (TiO2) thin film is synthesized by electrospinning features porous structure composed by TiO2 nanowires with random orientations. The porous structure caused significant degradation of thermal properties. Effective thermal diffusivity, conductivity, and density of the films are 1.35˜3.52 × 10-6 m2/s, 0.06˜0.36 W/m·K, and

  18. Thermo-physical properties of (Th,U)O2

    International Nuclear Information System (INIS)

    Yang, J. H.; Gang, K. W.; Lee, C. B.

    2003-01-01

    The temperature dependance of thermal expansion, thermal diffusivity and thermal conductivity in (Th 1-y U y )O 2 (y=0.0, 0.345, 0.645) system has been measured using dillatomeler and laser flash apparatus. The thermal expansion of (Th 1-y U y )0 2 linearly increases with U mole fraction y in the measured temperature range. The thermal conductivities of (Th 0.655 U 0. 3 45 )0 2 and (Th 0.. 3 55 U 0.645 )0 2 fuel were found to be lower than that of Th0 2 or U0 2 fuel The degradation of the thermal conductivity by the addition of U0 2 is large at low temperatures but becomes smaller as the temperature increases. The phonon -defect scattering might be associated with the degradation of the thermal conductivity. The measured thermo-physical properties of (Th,U)O 2 system can be well described in terms of the formation of a complete solid solution in the whole composibon range

  19. Thermophysical properties of ethylene glycol mixture based CNT nanofluids

    Science.gov (United States)

    Camarano, D. M.; Mansur, F. A.; Araújo, T. L. C. F.; Salles, G. C.; Santos, A. P.

    2016-07-01

    Nanofluids are produced by dispersing nanometer-scale solid particles into base liquids such as water, ethylene glycol, etc. The thermal quadrupole method is utilized to determine the thermophysical properties of materials. By this technique, the thermal diffusivity and conductivity of different nanofluids containing the surfactants humic acid, sodium salt of humic acid and sodium carboxymethyl cellulose and multi-wall carbon nanotubes were evaluated at room temperature and at 75 oC. Values of thermal diffusivity varying in the range from 9.60x10-8 m2s-1 to 1.46x10-7 m2s-1 and thermal conductivity from 0.26 Wm-1K-1 to 41 Wm-1K-1 were obtained. As main conclusions, it was noted that nanofluids exhibit superior heat transfer characteristics than the conventional heat transfer fluid and the thermal conductivity is enhanced by 50% for the nanofluid containing 0.0275 mg/mL of sodium salt of humic acid + ethylene glycol, at the temperature of 25 oC.

  20. Engineering Database of Liquid Salt Thermophysical and Thermochemical Properties

    Energy Technology Data Exchange (ETDEWEB)

    Manohar S. Sohal; Matthias A. Ebner; Piyush Sabharwall; Phil Sharpe

    2010-03-01

    The purpose of this report is to provide a review of thermodynamic and thermophysical properties of candidate molten salt coolants, which may be used as a primary coolant within a nuclear reactor or heat transport medium from the Next Generation Nuclear Plant (NGNP) to a processing plant, for example, a hydrogen-production plant. Thermodynamic properties of four types of molten salts, including LiF-BeF2 (67 and 33 mol%, respectively; also known as FLiBe), LiF-NaF-KF (46.5, 11.5, and 52 mol%, also known as FLiNaK), and KCl-MgCl2 (67 and 33 mol%), and sodium nitrate-sodium nitrite-potassium nitrate (NaNO3–NaNO2–KNO3, (7-49-44 or 7-40-53 mol%) have been investigated. Limitations of existing correlations to predict density, viscosity, specific heat capacity, surface tension, and thermal conductivity, were identified. The impact of thermodynamic properties on the heat transfer, especially Nusselt number was also discussed. Stability of the molten salts with structural alloys and their compatibility with the structural alloys was studied. Nickel and alloys with dense Ni coatings are effectively inert to corrosion in fluorides but not so in chlorides. Of the chromium containing alloys, Hastelloy N appears to have the best corrosion resistance in fluorides, while Haynes 230 was most resistant in chloride. In general, alloys with increasing carbon and chromium content are increasingly subject to corrosion by the fluoride salts FLiBe and FLiNaK, due to attack and dissolution of the intergranular chromium carbide. Future research to obtain needed information was identified.

  1. Reference on Thermophysical Properties: Density and Viscosity of Several Gases by Using Macro Excel (RSSDFIUSK vs. 1

    Directory of Open Access Journals (Sweden)

    Elin Yusibani

    2015-09-01

    Full Text Available A source code for calculating reference on thermophysical properties: density and viscosity for several gases (nitrogen, helium, hydrogen, argon and air has been developed under Visual Basic for Applications (VBA programming in MS Excel (as a macros. Selected density and viscosity equations have been chosen as a basic equation in the VBA programming as a user-defined function. This macro is very useful for engineers and researchers due to enhance their experimental and/or theoretical studies.

  2. Reference on Thermophysical Properties: Density and Viscosity of Several Gases by Using Macro Excel (RSSDFIUSK Vs. 1)

    OpenAIRE

    Yusibani, Elin

    2015-01-01

    A source code for calculating reference on thermophysical properties: density and viscosity for several gases (nitrogen, helium, hydrogen, argon and air) has been developed under Visual Basic for Applications (VBA) programming in MS Excel (as a macros). Selected density and viscosity equations have been chosen as a basic equation in the VBA programming as a user-defined function. This macro is very useful for engineers and researchers due to enhance their experimental and/or theoretical studies.

  3. A new method to determine thermophysical properties of PCM-concrete brick

    DEFF Research Database (Denmark)

    Cheng, Rui; Pomianowski, Michal Zbigniew; Wang, Xin

    2013-01-01

    Accurate measurement of thermophysical properties of PCM-concrete brick is very important for simulation and evaluation of its energy saving performance. However, there is currently no effective way to accurately measure thermophysical properties of PCM-concrete brick. First we analyzed...... the shortcomings of using traditional testing methods to measure thermophysical properties of PCM-concrete brick. We then proposed a new method based on the inverse problem, which deals with the measurements of thermal conductivity and specific heat of PCM-concrete brick during the phase change process....... The equivalent specific heat distributions of 4 wt% and 6 wt% PCM-concrete brick were determined using this method. We found that the accuracy (the relative error of the calculated cp based on the inverse problem and their real values ranges from 10.43% to 19.4%) was acceptable for engineering use...

  4. Composition-Based Prediction of Temperature-Dependent Thermophysical Food Properties: Reevaluating Component Groups and Prediction Models.

    Science.gov (United States)

    Phinney, David Martin; Frelka, John C; Heldman, Dennis Ray

    2017-01-01

    Prediction of temperature-dependent thermophysical properties (thermal conductivity, density, specific heat, and thermal diffusivity) is an important component of process design for food manufacturing. Current models for prediction of thermophysical properties of foods are based on the composition, specifically, fat, carbohydrate, protein, fiber, water, and ash contents, all of which change with temperature. The objectives of this investigation were to reevaluate and improve the prediction expressions for thermophysical properties. Previously published data were analyzed over the temperature range from 10 to 150 °C. These data were analyzed to create a series of relationships between the thermophysical properties and temperature for each food component, as well as to identify the dependence of the thermophysical properties on more specific structural properties of the fats, carbohydrates, and proteins. Results from this investigation revealed that the relationships between the thermophysical properties of the major constituents of foods and temperature can be statistically described by linear expressions, in contrast to the current polynomial models. Links between variability in thermophysical properties and structural properties were observed. Relationships for several thermophysical properties based on more specific constituents have been identified. Distinctions between simple sugars (fructose, glucose, and lactose) and complex carbohydrates (starch, pectin, and cellulose) have been proposed. The relationships between the thermophysical properties and proteins revealed a potential correlation with the molecular weight of the protein. The significance of relating variability in constituent thermophysical properties with structural properties--such as molecular mass--could significantly improve composition-based prediction models and, consequently, the effectiveness of process design. © 2016 Institute of Food Technologists®.

  5. A thermophysical properties data base management system for reactor materials on the microcomputers

    International Nuclear Information System (INIS)

    Zhong Jianguo

    1995-01-01

    The thermophysical properties data base management system, named as TPSYS, is designed to store and manage the information on thermophysical properties of solid and liquid materials. Modular programmed, TPSYS is primarily written with dBASE-III PLUS language, C language is adopted in the plotting program and FORTRAN language is used for computing and data processing. In addition to the routine functions of DBMS, it has the module of executing the large calculation program MATPRO and the module of interfacing with the present DBMS THERSYST. Running on IBM-PC (386, 486) and compatible computers with the system of DOS 3.3, TPSYS is popular and user-friendly

  6. Reference Correlations for Thermophysical Properties of Liquid Water at 0.1 MPa

    Czech Academy of Sciences Publication Activity Database

    Pátek, Jaroslav; Hrubý, Jan; Klomfar, Jaroslav; Součková, Monika; Harvey, A.H.

    2009-01-01

    Roč. 38, č. 1 (2009), s. 21-29 ISSN 0047-2689 R&D Projects: GA AV ČR IAA200760701 Institutional research plan: CEZ:AV0Z20760514 Keywords : water * thermophysical properties * transport properties * calibration Subject RIV: BJ - Thermodynamics Impact factor: 2.093, year: 2009

  7. Molecular shape and thermophysical properties of liquids. II. Thermal properties

    International Nuclear Information System (INIS)

    Adamenko, Yi.Yi.; Grigor'jev, A.M.; Kuzovkov, Yu.G.; Mironenko, O.K.

    2009-01-01

    Isobaric and isochoric heat capacities, thermal expansion coefficient and enthalpy of soft dumb-bell fluids were determined in Monte Carlo simulations in a wide range of reduced densities and pressures. Molecular nonsphericity influence on pressure dependencies of elastic thermal properties was analyzed.

  8. Thermophysical Property Estimation by Transient Experiments: The Effect of a Biased Initial Temperature Distribution

    Directory of Open Access Journals (Sweden)

    Federico Scarpa

    2015-01-01

    Full Text Available The identification of thermophysical properties of materials in dynamic experiments can be conveniently performed by the inverse solution of the associated heat conduction problem (IHCP. The inverse technique demands the knowledge of the initial temperature distribution within the material. As only a limited number of temperature sensors (or no sensor at all are arranged inside the test specimen, the knowledge of the initial temperature distribution is affected by some uncertainty. This uncertainty, together with other possible sources of bias in the experimental procedure, will propagate in the estimation process and the accuracy of the reconstructed thermophysical property values could deteriorate. In this work the effect on the estimated thermophysical properties due to errors in the initial temperature distribution is investigated along with a practical method to quantify this effect. Furthermore, a technique for compensating this kind of bias is proposed. The method consists in including the initial temperature distribution among the unknown functions to be estimated. In this way the effect of the initial bias is removed and the accuracy of the identified thermophysical property values is highly improved.

  9. Science at Home: Measuring a Thermophysical Property of Water with a Microwave Oven

    Science.gov (United States)

    Levine, Zachary H.

    2018-01-01

    An attempt to calibrate a conventional oven led to making a measurement of a thermophysical property of water using items found in the author's home. Specifically, the ratio of the energy required to heat water from the melting point to boiling to the energy required to completely boil away the water is found to be 5.7. This may be compared to the…

  10. Thermophysical properties of cement based composites and their changes after artificial ageing

    Science.gov (United States)

    Šín, Peter; Pavlendová, Gabriela; Lukovičová, Jozefa; Kopčok, Michal

    2017-07-01

    The usage of recycled plastic materials in concrete mix gained increased attention. The behaviour of such environmental friendly material is studied. In this paper an investigation of the thermophysical properties of cement based composites containing plastic waste particles with different percentage is presented. Measurements were carried out using pulse transient method before and after artificial ageing in climatic chamber BINDER MKF (E3).

  11. Thermophysical properties of yacon (Smallanthus sonchifolius: experimental determination and effect of moisture content

    Directory of Open Access Journals (Sweden)

    Camila Augusto Perussello

    2015-01-01

    Full Text Available The knowledge about thermophysical properties of foods is especially important in thermal processing, influencing the design, optimization and cost reduction of the process, as well as the quality and safety of the final product. This article deals with the determination of some thermophysical properties of yacon, namely, specific mass, specific heat, thermal conductivity and thermal diffusivity during the osmo-convective drying. Yacon is a root with approximately 90% w.b. of moisture content, whose high concentration of fructooligosacharydes and antioxidants has gained attention in the food research field. Yacon slices were osmotically dehydrated for 2 hours in a sucralose solution and then dried in a convective tray dryer for 2 hours, varying the osmotic solution’s temperature and stirring rate and temperature of the drying air. All thermophysical properties were determined during the drying process at 30-minute intervals. The thermophysical properties were determined not only experimentally but also calculated by models available in literature based on the product’s centesimal composition. A satisfactory agreement between experimental and predicted results was obtained. Further, empirical models obtained by nonlinear regression were successfully fitted to the experimental data, as a function of moisture content, within a 94% - 3% w.b. range.

  12. Sensitivity analyses of biodiesel thermo-physical properties under diesel engine conditions

    DEFF Research Database (Denmark)

    Cheng, Xinwei; Ng, Hoon Kiat; Gan, Suyin

    2016-01-01

    This reported work investigates the sensitivities of spray and soot developments to the change of thermo-physical properties for coconut and soybean methyl esters, using two-dimensional computational fluid dynamics fuel spray modelling. The choice of test fuels made was due to their contrasting s...

  13. Thermal, Thermophysical, and Compositional Properties of the Moon Revealed by the Diviner Lunar Radiometer

    Science.gov (United States)

    Greenhagen, B. T.; Paige, D. A.

    2012-01-01

    The Diviner Lunar Radiometer is the first multispectral thermal instrument to globally map the surface of the Moon. After over three years in operation, this unprecedented dataset has revealed the extreme nature of the Moon's thermal environment, thermophysical properties, and surface composition.

  14. Some thermo-physical properties of yam cuts of two geometries ...

    African Journals Online (AJOL)

    The effects of variation of temperature (-18 to 33°C) and geometries (slab and cylinder) on some thermo-physical properties of white yam were investigated. The measured parameters were density, specific heat, and thermal diffusivity at constant moisture level of 72.7% ± 0.69 (wet basis) using transient heat transfer method ...

  15. Validation of forcefields in predicting the physical and thermophysical properties of emeraldine base polyaniline

    NARCIS (Netherlands)

    Chen, X.P.; Yuan, C.A.; Wong, C.K.Y.; Koh, S.W.; Zhang, G.Q.

    2011-01-01

    We report a molecular modelling study to validate the forcefields [condensed-phase optimised molecular potentials for atomistic simulation studies (COMPASS) and polymer-consistent forcefield (PCFF)] in predicting the physical and thermophysical properties of polymers. This work comprises of two key

  16. REFERENCE ON THERMOPHYSICAL PROPERTIES: DENSITY AND VISCOSITY OF WATER FOR ATMOSPHERIC PRESSURE

    OpenAIRE

    Elin Yusibani; Aprina .; Teuku Khairuman

    2016-01-01

    A reference on thermophysical properties, density and viscosity, for water at atmospheric pressure has been developed in MS Excel (as a macros). Patterson’s density equations and Kestin’s viscosity equations have been chosen as a basic equation in the VBA programming as a user-defined function. These results have been compared with REFPROF as a wellknow standart reference

  17. Reference on Thermophysical Properties: Density and Viscosity of Water for Atmospheric Pressure

    OpenAIRE

    Yusibani, Elin; Aprina; Khairuman, Teuku

    2016-01-01

    A reference on thermophysical properties, density and viscosity, for water at atmospheric pressure has been developed in MS Excel (as a macros). Patterson's density equations and Kestin's viscosity equations have been chosen as a basic equation in the VBA programming as a user-defined function. These results have been compared with REFPROF as a wellknow standart reference

  18. Thermo-Physical Properties of Kenaf-Filled Acrylonitrile Butadiene Styrene Composites

    Directory of Open Access Journals (Sweden)

    Nikmatin Siti

    2017-01-01

    Full Text Available Studies on advantageous of natural fillers incorporated into polymer composites on thermo-physical and mechanical properties are still intensively investigated. Several evidences suggest that the natural fillers with small contents combined with polymer increase their composite properties. We thus investigate thermo-physical properties of kenaf-filled acrylonitrile butadiene styrene (ABS composites. ABS with 5% kenaf microparticle size (ABS/K5, ABS with 5% kenaf short fiber (ABS/KSF5, and recycled ABS with 5% kenaf microparticle size (RABS/K5 were manufactured. Granular composites were manufactured by the twin screw extruder. Composite properties in terms of X-ray diffractions, surface morphologies, and thermal behaviors were investigated. The present work found that ABS/KSF5 has the highest degree of crystallinity compared to others. No significant difference was found in terms of thermal properties of the composites.

  19. Kinetic and thermophysical studies of acetamide-sodium bromide eutectic for low temperature storage applications

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, S.K.; Sethi, B.P.S.; Chopra, Suneeta (Panjab Univ., Chandigarh (IN). Energy Research Centre)

    1992-02-01

    The kinetics of thermal decomposition of acetamide-sodium bromide using a Differential Scanning Calorimeter and a Differential Thermogravimetric Analyser have been reported. The kinetic parameters have been evaluated using Zsako's method using 10 different mechanisms, such as nucleation, nuclei growth and diffusion. The thermophysical properties, such as density and viscosity, which have a profound effect on the design of the heat exchanger and crystallization have been evaluated and reported. The results show that the eutectic has favourable characteristics, namely low volume change, high energy storage density, high heat of fusion, good thermal stability and favourable crystallization characteristics. The eutectic could find use in thermal energy storage applications for commercial and laundry water heating, process heating hot water, process heating hot air, crop drying and food warming in the hotel industry. (Author).

  20. Mechanical and Thermophysical Properties of Cement and/or Paper (Cellulose Stabilized Compressed Clay Bricks

    Directory of Open Access Journals (Sweden)

    Emmanuel OUEDRAOGO

    2015-05-01

    Full Text Available This article presents an experimental study of the characterization of clay blocks stabilized with cement and/or recycled papers as construction materials. When they are utilized as finish for building envelops, they must have appropriate mechanical strength and water stability. The measurements of the mechanical and thermophysical properties show differences between the properties of four investigated specimens. Mechanical properties such as compression and tensile tresses of clay-cement and clay-cement-paper mixtures are found to be quite similar but are two to three times greater respectively for clay-paper and purely clay blocks. The values of the thermophysical properties of blocks incorporating paper show improvement of their thermo insulation performances.

  1. Fluorination effects on the thermodynamic, thermophysical and surface properties of ionic liquids

    International Nuclear Information System (INIS)

    Vieira, N.S.M.; Luís, A.; Reis, P.M.; Carvalho, P.J.; Lopes-da-Silva, J.A.; Esperança, J.M.S.S.; Araújo, J.M.M.; Rebelo, L.P.N.; Freire, M.G.; Pereiro, A.B.

    2016-01-01

    Highlights: • Surface tension of fluorinated ionic liquids. • Thermophysical properties of fluorinated ionic liquids. • Thermal properties and thermodynamic functions. - Abstract: This paper reports the thermal, thermodynamic, thermophysical and surface properties of eight ionic liquids with fluorinated alkyl side chain lengths equal or greater than four carbon atoms. Melting and decomposition temperatures were determined together with experimental densities, surface tensions, refractive indices, dynamic viscosities and ionic conductivities in a temperature interval ranging from (293.15 to 353.15) K. The surface properties of these fluorinated ionic liquids were discussed and several thermodynamic functions, as well as critical temperatures, were estimated. Coefficients of isobaric thermal expansion, molecular volumes and free volume effects were calculated from experimental values of density and refractive index and compared with previous data. Finally, Walden plots were used to evaluate the ionicity of the investigated ionic liquids.

  2. INFLUENCE OF STORING AND TEMPERATURE ON RHEOLOGIC AND THERMOPHYSICAL PROPERTIES OF WHISKY SAMPLES

    Directory of Open Access Journals (Sweden)

    Peter Hlavac

    2013-09-01

    Full Text Available Temperature and storing time can be included between the most significant parameters that influence physical properties of food. This article deals with selected rheologic and thermophysical properties of alcohol drink whisky. Our research was oriented on measuring of rheologic and thermophysical characteristics of whisky. There were measured two types of whisky Grant s and Jim Beam from two different producers, both samples had 40 percent of alcohol content. During the experiments were analyzed rheologic parameters as dynamic viscosity, kinematic viscosity and fluidity and thermophysical parameters as thermal conductivity, thermal diffusivity and volume specific heat. Selected parameters were measured in temperature range 5 to 27 C. Measurements were done on whisky samples in different days during the storage. Measuring of dynamic viscosity was performed by digital rotational viscometer Anton Paar. Principle of measuring is based on dependency of sample resistance against the probe rotation. Density of whisky samples was determined by pycnometric method. Average density at given temperature along with dynamic viscosity value was used at calculation of kinematic viscosity and fluidity was also determined. Measuring of thermophysical parameters was performed by instrument Isomet 2104 Measurement by Isomet is based on analysis of the temperature response of the measured sample to heat flow impulses. Relations of rheologic and thermophysical parameters to the temperature were made and influence of storing time was discussed. From obtained results is clear that dynamic and kinematic viscosity is decreasing exponentially with temperature and fluidity has increasing exponential progress. We found out that both whisky samples had at the beginning and after one week of storage very similar values of rheologic parameters. Very small difference in rheologic parameters of whisky samples was found after two weeks of storing. Values of dynamic and kinematic

  3. The Importance of Thermophysical Properties of Steels for the Numerical Simulation of a Concasting Process

    Directory of Open Access Journals (Sweden)

    Frantisek KAVICKA

    2010-12-01

    Full Text Available The thermophysical properties of steels have significant influence on the actual concasting process, and on the accuracy of its numerical simulation and optimization. The determination of these properties (heat conductivity, specific heat capacity and density in the solid and liquid states often requires more time than the actual numerical calculation of the temperature fields of a continuously cast steel billet, cylinder or slab (generally a concasting. The influence of individual properties should be neither under- nor over-estimated. Therefore, an analysis/parametric study of these thermophysical properties was conducted. The order of importance within the actual process and the accuracy of simulation and optimization were also determined. Individual properties, which, in some cases, were obtained from tables, and in others experimentally, were substituted by an approximation using orthogonal polynomials. The accuracy of each polynomial is dependent on the precision of individual values. The order of significance of individual thermophysical properties was determined with respect to the metallurgical length. The analysis was performed by means of a so-called calculation experiment, i.e. by means of the original and universal numerical concasting model developed by the authors of this paper. It is convenient to conduct such an analysis in order to facilitate the simulation of each individual case of concasting, thus enhancing the process of optimization.

  4. Thermophysical properties of rocks: a perspective on data needs, sources and accuracy

    International Nuclear Information System (INIS)

    Stephens, H.P.; Sinnock, S.

    1979-01-01

    Recent emphasis on research in geologic isolation of nuclear wastes and geoenergy resource development has created a renewed demand for engineering thermophysical property data for rocks and other geologic materials at elevated pressures and temperatures. In contrast to fabricated engineering materials, with properties which can be specified, rocks used in engineering design are complex, naturally occurring materials having properties which must be characterized, rather than specified, for engineering studies. Much difficulty in measuring, reporting, and using thermophysical properties of rocks results from (1) rock inhomogeneity and anisotropy on both microscopic and macroscopic scales; (2) inclusion of pore fluids, such as water; and (3) measurement of laboratory properties under conditions quite different from those of in situ material. Because measurements on in situ materials are scarce, many analyses must depend on extrapolated values of uncertain accuracy. A survey of thermophysical property data available for geologic thermal transport studies indicates that caution must be taken to effectively match data abstracted from the literature with project objectives

  5. Influence of accelerated thermal charging and discharging cycles on thermo-physical properties of organic phase change materials for solar thermal energy storage applications

    International Nuclear Information System (INIS)

    Raam Dheep, G.; Sreekumar, A.

    2015-01-01

    Highlights: • Identification of organic phase change materials namely benzamide and sebacic acid. • Thermal reliability studies on identified phase change materials. • Measurement of phase transition temperature and latent heat of fusion. • Analysis of relative percentage difference (RPD%) in heat of fusion and melting temperature of benzamide and sebacic acid. - Abstract: Integration of appropriate thermal energy storage system plays a predominant role in upgrading the efficiency of solar thermal energy devices by reducing the incongruity between energy supply and demand. Latent heat thermal energy storage based on phase change materials (PCM) is found to be the most efficient and prospective method for storage of solar thermal energy. Ensuring the thermal reliability of PCM through large number of charging (melting) and discharging (solidification) cycles is a primary prerequisite to determine the suitability of PCM for a specific thermal energy storage applications. The present study explains the experimental analysis carried out on two PCM’s namely benzamide and sebacic acid to check the compatibility of the material in solar thermal energy storage applications. The selected materials were subjected to one thousand accelerated melting and solidification cycles in order to investigate the percentage of variation at different stages on latent heat of fusion, phase transition temperature, onset and peak melting temperature. Differential Scanning Calorimeter (DSC) was used to determine the phase transition temperature and heat of fusion upon completion of every 100 thermal cycles and continued up to 1000 cycles. Relative Percentage Difference (RPD%) is calculated to find out the absolute deviation of melting temperature and latent heat of fusion with respect to zeroth cycle. The experimental study recorded a melting temperatures of benzamide and sebacic acid as 125.09 °C and 135.92 °C with latent heat of fusion of 285.1 (J/g) and 374.4 (J/g). The

  6. Thermophysical properties. Progress report, 1 January 1992--31 March 1993

    Energy Technology Data Exchange (ETDEWEB)

    Kayser, R.F.

    1993-04-01

    Numerous fluids have been identified as promising alternative refrigerants, but much of the information needed to predict their behavior as pure fluids and as components in mixtures does not exist. In particular, reliable thermophysical properties data and models are needed to predict the performance of the new refrigerants in heating and cooling equipment and to design and optimize equipment to be reliable and energy efficient. The objective of this fifteen-month project has been to provide highly accurate, selected thermophysical properties data for Refrigerants 32, 123, 124, and 125, and to use these data to fit equations of state and transport property models. The new data have filled gaps in the existing data sets and resolved problems and uncertainties that existed in and between the data sets.

  7. Thermophysical properties. Quarterly report, 1 July 1992--30 September 1992

    Energy Technology Data Exchange (ETDEWEB)

    Kayser, R.F.

    1992-10-01

    Numerous fluids have been identified as promising alternative refrigerants, but much of the information needed to predict their behavior as pure fluids and as components in mixtures does not exist. In particular, reliable thermophysical properties data and models are needed to predict the performance of the new refrigerants in heating and cooling equipment, and to design and optimize equipment to be reliable and energy efficient. Objective of this project is to provide highly accurate, selected thermophysical properties data for Refrigerants 32, 123, 124, and 125, and to use these data to fit simple and complex equations of state and detailed transport property models. The new data will fill gaps in the existing data sets and resolve the problems and uncertainties that exist in and between the data sets. This report describes the progress made during the third quarter of this fifteen-month project, which was initiated in late January, 1992.

  8. Thermophysical properties. Quarterly report, 1 October 1992--31 December 1992

    Energy Technology Data Exchange (ETDEWEB)

    Kayser, R.F.

    1993-01-01

    Numerous fluids have been identified as promising alternative refrigerants, but much of the information needed to predict their behavior as pure fluids and as components in mixtures does not exist. In particular, reliable thermophysical properties data and models are needed to predict the performance of the new refrigerants in heating and cooling equipment and to design and optimize equipment to be reliable and energy efficient. The objective of this project is to provide highly accurate, selected thermophysical properties data for Refrigerants 32, 123, 124, and 125, and to use these data to fit simple and complex equations of state and detailed transport property models. The new data will fill gaps in the existing data sets and resolve the problems and uncertainties that exist in and between the data sets. This report describes the progress made during the fourth quarter of this fifteen-month project, which was initiated in late January, 1992.

  9. Thermophysical properties of the Lipari lavas (Southern Tyrrhenian Sea

    Directory of Open Access Journals (Sweden)

    D. Russo

    1997-06-01

    Full Text Available Results of thermophysical investigations into the lavas of the island of Lipari (Southern Tyrrhenian Sea are presented. Samples selected for laboratory measurements belong to four main magmatic cycles, which produced basaltic-andesitic, andesitic and rhyolitic lavas. The wet-bulk density and the thermal conductivity measured on 69 specimens range from 1900 to 2760 kg m-3 and from 1.02 to 2.88 W m-1 K-1, respectively. Porosity is never negligible and its influence on density is maximum in rhyolites of the third cycle. The thermal conductivity is also influenced by the amount of glass. Rhyolitic obsidians show values lower than other rhyolites, although the latter rocks have a larger average porosity. The radioactive heat production determined on 36 specimens varies with the rock type, depending on the amount of U, Th and K. In basic lavas of the first cycle its value is 0.95°± 0.30 mW m-3, while in rhyolites of the fourth cycle it attains 6.68°±0.61 mW m-3. A comparison between results of g-ray spectrometry and X-ray fluorescence points out that the assumption of equilibrium in the decay series of the isotopic elements seems fulfilled. The information obtained is useful not only for the interpretation of geophysical surveys but also for the understanding of the geochemical characteristics of lavas.

  10. Dispersion stability and thermophysical properties of environmentally friendly graphite oil–based nanofluids used in machining

    Directory of Open Access Journals (Sweden)

    Yu Su

    2016-01-01

    Full Text Available As environmentally friendly cutting fluids, vegetable-based oil and ester oil are being more and more widely used in metal cutting industry. However, their cooling and lubricating properties are required to be further improved in order to meet more cooling and lubricating challenges in high-efficiency machining. Nanofluids with enhanced heat carrying and lubricating capabilities seem to give a promising solution. In this article, graphite oil–based nanofluids with LB2000 vegetable-based oil and PriEco6000 unsaturated polyol ester as base fluids were prepared by ultrasonically assisted two-step method, and their dispersion stability and thermophysical properties such as viscosity and thermal conductivity were experimentally and theoretically investigated at different ultrasonication times. The results indicate that graphite-PriEco6000 nanofluid showed better dispersion stability, higher viscosity, and thermal conductivity than graphite-LB2000 nanofluid, which made it more suitable for application in high-efficiency machining as coolant and lubricant. The theoretical classical models showed good agreement with the thermal conductivity values of graphite oil–based nanofluids measured experimentally. However, the deviation between the experimental values of viscosity and the theoretical models was relatively big. New empirical correlations were proposed for predicting the viscosity of graphite oil–based nanofluids at various ultrasonication times.

  11. Synthesis and thermophysical properties of AMoO4 (A = Ca, Sr, Ba)

    International Nuclear Information System (INIS)

    Maji, Binoy Kumar; Jena, Hrudananda; Asuvathraman, R.; Govindan Kutty, K.V.

    2013-01-01

    The alkaline earth molybdates AMoO 4 (A=Ca, Sr, Ba) belong to Scheelite type crystal structure with space group 14 1 /a, and are naturally occurring minerals. They are often found as secondary phases in irradiated oxide nuclear fuels as a product of fission product interaction. These compounds can also form as microcrystallites when the high-level nuclear waste is vitrified. As high temperature ceramics, they find applications as sensor materials, oxide ion conductors, etc. The thermophysical properties of these molybdates are essential for understanding their impact on the high temperature properties of the systems and devices containing them. In the present study, these compounds were synthesized by solid state reaction route in air at 823 K, and characterized by powder XRD and TG/DTA. The thermal expansion behavior was investigated by dilatometry in the temperature range of 300-800 K in air. The % thermal expansion of BaMoO 4 was found to be the lowest among the three compounds. The electrical conductivity of the compounds was measured by AC-impedance spectroscopy, and the conductivity was found to be in the range of 10 -4 S.cm -1 at 1073 K in air. The activation energy of electrical conduction was measured to be about 1.3 eV. (author)

  12. Structure and Thermophysical Properties of Molten BaGe Using Electrostatic Levitation Technique

    Science.gov (United States)

    Ishikura, Akiko; Mizuno, Akitoshi; Watanabe, Masahito; Masaki, Tadahiko; Ishikawa, Takehiko; Yoda, Shinichi

    2008-12-01

    BaGe alloys with two compositions near their eutectic point form open framework structures called the clathrate structure. These BaGe compounds with the clathrate structure can be made by rapid solidification from their liquid state. However, the formation mechanism of the clathrate structure has not been clarified due to lack of information on their liquid-state structure and properties. Since BaGe alloy melts have very high reactivity, it is difficult to measure the thermophysical properties of them by ordinary methods using a container. Therefore, a containerless technique must be used to measure the thermophysical properties of BaGe melts. Using the electrostatic levitation (ESL) technique as a containerless technique, the thermophysical properties (density, surface tension, and viscosity) of BaGe melts around the eutectic composition were measured in order to clarify the formation mechanism of the clathrate structure, and also the structure of them was observed by using the high-energy X-ray diffraction method combined with ESL. From experimental results, it was observed that the short-range order based on the clathrate structure exists even in the liquid state at the clathrate-forming compositions.

  13. Review on Synthesis, Thermo-Physical Property, and Heat Transfer Mechanism of Nanofluids

    Directory of Open Access Journals (Sweden)

    Mahesh Suresh Patil

    2016-10-01

    Full Text Available Nanofluids are suspended nano-sized particles in a base fluid. With increasing demand for more high efficiency thermal systems, nanofluids seem to be a promising option for researchers. As a result, numerous investigations have been undertaken to understand the behaviors of nanofluids. Since their discovery, the thermo-physical properties of nanofluids have been under intense research. Inadequate understanding of the mechanisms involved in the heat transfer of nanofluids has been the major obstacle for the development of sophisticated nanofluids with the desired properties. In this comprehensive review paper, investigations on synthesis, thermo-physical properties, and heat transfer mechanisms of nanofluids have been reviewed and presented. Results show that the thermal conductivity of nanofluids increases with the increase of the operating temperature. This can potentially be used for the efficiency enhancement of thermal systems under higher operating temperatures. In addition, this paper also provides details concerning dependency of the thermo-physical properties as well as synthesis and the heat transfer mechanism of the nanofluids.

  14. Modified T-history method for measuring thermophysical properties of phase change materials at high temperature

    Science.gov (United States)

    Omaraa, Ehsan; Saman, Wasim; Bruno, Frank; Liu, Ming

    2017-06-01

    Latent heat storage using phase change materials (PCMs) can be used to store large amounts of energy in a narrow temperature difference during phase transition. The thermophysical properties of PCMs such as latent heat, specific heat and melting and solidification temperature need to be defined at high precision for the design and estimating the cost of latent heat storage systems. The existing laboratory standard methods, such as differential thermal analysis (DTA) and differential scanning calorimetry (DSC), use a small sample size (1-10 mg) to measure thermophysical properties, which makes these methods suitable for homogeneous elements. In addition, this small amount of sample has different thermophysical properties when compared with the bulk sample and may have limitations for evaluating the properties of mixtures. To avoid the drawbacks in existing methods, the temperature - history (T-history) method can be used with bulk quantities of PCM salt mixtures to characterize PCMs. This paper presents a modified T-history setup, which was designed and built at the University of South Australia to measure the melting point, heat of fusion, specific heat, degree of supercooling and phase separation of salt mixtures for a temperature range between 200 °C and 400 °C. Sodium Nitrate (NaNO3) was used to verify the accuracy of the new setup.

  15. Thermophysical properties of inorganic polysulfides. Technical progress report. [Na/sub 2/S/sub 3/

    Energy Technology Data Exchange (ETDEWEB)

    Janz, G J

    1979-12-01

    The present project was initiated May 15, 1979, and was undertaken to meet the data needs for thermophysical properties of selected polysulfides, as required directly or indirectly in the advanced battery development programs, and to advance the theoretical studies on the mechanisms of melting of ionic compounds. The research approach is briefly summarized and the accomplishments and status of the three principal tasks that have been undertaken in this initial period are reported: preparative chemistry; the MSDC-RPI DSC facility; and thermophysical properties measurements. First results for sodium trisulfide for the melting point, the enthalpy of fusion, and entrophy of fusion are 238.7/sup 0/C, 5538 cal/mol, and 10.83 cal/deg mol. 1 figure, 6 tables.

  16. Thermophysical properties estimation of paraffin/graphite composite phase change material using an inverse method

    International Nuclear Information System (INIS)

    Lachheb, Mohamed; Karkri, Mustapha; Albouchi, Fethi; Mzali, Foued; Nasrallah, Sassi Ben

    2014-01-01

    Highlights: • Preparation of paraffin/graphite composites by uni-axial compression technique. • Measurement of thermophysical properties of paraffin/graphite using the periodic method. • Measurement of the experimental densities of paraffin/graphite composites. • Prediction of the effective thermal conductivity using analytical models. - Abstract: In this paper, two types of graphite were combined with paraffin in an attempt to improve thermal conductivity of paraffin phase change material (PCM): Synthetic graphite (Timrex SFG75) and graphite waste obtained from damaged Tubular graphite Heat Exchangers. These paraffin/graphite phase change material (PCM) composites are prepared by the cold uniaxial compression technique and the thermophysical properties were estimated using a periodic temperature method and an inverse technique. Results showed that the thermal conductivity and thermal diffusivity are greatly influenced by the graphite addition

  17. Experimental investigation of thermophysical properties of eutectic Re-C at high temperatures

    Science.gov (United States)

    Belikov, R. S.; Senchenko, V. N.; Sulyanov, S. N.

    2018-01-01

    Using the previously described experimental setup for investigation of thermophysical properties of refractory materials under high pressures and temperatures a few experiments with samples of cast eutectic Re-C were carried out. The experimental technique was extended for millisecond electrical heating of the samples under the high static pressure of inert gas. First experimental data on the specific enthalpy, specific heat capacity and linear thermal expansion of ReC0.3 were obtained.

  18. Effects of superplastic deformations on thermophysical properties of tetragonal zirconia polycrystals

    International Nuclear Information System (INIS)

    Motohashi, Y.; Wan, C.; Sakuma, T.; Harjo, S.; Shibata, T.; Ishihara, M.; Baba, S.; Hoshiya, T.

    2004-01-01

    Neutron irradiation studies on superplastic zirconia-based ceramics are now in progress as an innovative basic project using the High-temperature Engineering Test Reactor (HTTR) in Japan. The characteristics of the zirconia-based engineering components, made through the formation of superplastic, may be strongly affected by their response to transient or steady-state heat flow. Reliable thermophysical properties such as the coefficients of thermal expansion and thermal conductivity are, therefore, needed to estimate and predict the influence of a high-temperature environment. Accordingly, one of this project's targets is to study the thermophysical properties of superplastic zirconia-based ceramics. The first stage of the research addresses the effects of superplastic deformations on the thermophysical properties of a typical superplastic ceramic, 3 mol% yttria-stabilised tetragonal zirconia polycrystals (3Y-TZP), in its un-irradiated state. First, superplastic tensile deformations were conducted on 3Y-TZP specimens under different conditions in order to obtain specimens with different microstructural characteristics. Afterwards, the following actions were taken: - Specific heat measurements were conducted on the specimens at temperatures ranging from 473 K to 1273 K. - The thermal diffusivity was measured using a laser flash method. The thermal conductivity was then calculated from the measured thermal diffusivity, specific heat and density. - The linear thermal expansion was measured by a push-rod type dilatometer from 300 K to 1473 K. The coefficient of linear thermal expansion (CTE) was estimated from the thermal expansion data. The results obtained from the above measurements are discussed, as is the microstructural evolution caused by the superplastic deformations. It was found that the specific heat was almost independent of microstructural evolution, whereas the thermal diffusivity, thermal conductivity and thermal expansion were quite sensitive to

  19. REFERENCE ON THERMOPHYSICAL PROPERTIES: DENSITY AND VISCOSITY OF WATER FOR ATMOSPHERIC PRESSURE

    Directory of Open Access Journals (Sweden)

    Elin Yusibani

    2016-09-01

    Full Text Available A reference on thermophysical properties, density and viscosity, for water at atmospheric pressure has been developed in MS Excel (as a macros. Patterson’s density equations and Kestin’s viscosity equations have been chosen as a basic equation in the VBA programming as a user-defined function. These results have been compared with REFPROF as a wellknow standart reference

  20. A review on thermophysical properties of nanoparticle dispersed phase change materials

    International Nuclear Information System (INIS)

    Kibria, M.A.; Anisur, M.R.; Mahfuz, M.H.; Saidur, R.; Metselaar, I.H.S.C.

    2015-01-01

    Highlights: • Thermo physical properties of PCM could be enhanced by dispersing nanoparticles. • Surface/physical properties of nanoparticle could affect the thermal properties of PCM. • CNT and CNF showed better performance to enhance the thermal properties of PCM. • Some predictions in NePCM literature needs further investigations. - Abstract: A review of current experimental studies on variations in thermophysical properties of phase change material (PCM) due to dispersion of nanoparticles is presented in this article. Dispersed carbon nanotubes/fiber and different metal/metal oxide nano particles in paraffin and fatty acids might be a solution to improve latent heat thermal storage performance. Thermophysical properties such as thermal conductivity, latent heat, viscosity and super cooling of phase change materials (PCM) could be changed for different physical properties of dispersed nanoparticle such as size, shape, concentration and surface properties. Among the nano particles, comparatively carbon nanotubes and carbon nano fiber have shown better performance in enhancing the thermal properties of PCM for their unique properties. The present review will focus on the studies that describe how the surface, chemical and physical properties of nanoparticle could affect the thermal properties of PCM with the help of available explanations in the literature

  1. Wet flue gas desulphurisation procedures and relevant solvents thermophysical properties determination

    Directory of Open Access Journals (Sweden)

    Živković Nikola V.

    2014-01-01

    Full Text Available In order to mitigate climate change, the priority task is to reduce emissions of greenhouse gases, including sulfur oxides, from stationary power plants. The legal framework of the European Union has limited the allowable emissions of gases with harmful effects and fulfillment of this obligation is also ahead of the Republic of Serbia in the following years. In this paper categorization of wet procedures for sulfur oxides removal is given. Wet procedure with the most widespread industrial application, lime/limestone process, has been described in detail. In addition, the procedures with chemical and physical absorption and solvent thermal regeneration, which recently gained more importance, have been presented. Experimentally determined thermophysical and transport properties of commercially used and alternative solvents, necessary for the equipment design and process optimization, are also given in the paper. The obtained values of densities and viscosities of pure chemicals - solvents, polyethylene glycol 200 (PEG 200, polyethylene glycol 400 (PEG 400, tetraethylene glycol dimethyl ether (TEGDMA, N-methyl-2-pyrolidon (NMP and dimethylaniline (DMA, measured at the atmospheric pressure, are presented as a function of temperature. [Projekat Ministarstva nauke Republike Srbije, br. 172063

  2. Thermophysical characterization of sorption TCM

    NARCIS (Netherlands)

    Barreneche, C.; Fernández, A.I.; Cabeza, L.F.; Cuypers, R.

    2014-01-01

    Thermochemical materials (TCM) are proposed for thermal energy storage as one of the future options to achieve lower energy consumption in buildings and other industrial applications, as well as to store energy from solar energy. In this study, the thermophysical properties of two TCM, CaCl2 and

  3. Frequency Methods Applied to the Characterization of the Thermophysical Properties of a Granular Material with a Cylindrical Probe

    Science.gov (United States)

    Carpentier, Olivier; Defer, Didier; Antczak, Emmanuel; Chartier, Thierry

    2012-01-01

    In many fields, such as in the agri-food industry or in the building industry, it is important to be able to monitor the thermophysical properties of granular materials. Regular thermal probes allow for the determination of one or several thermophysical factors. The success of the method used depends in part on the nature of the signal sent, on the type of physical model applied and eventually on the type of probe used and its implantation in the material. Although efficacious for most applications, regular thermal probes do present some limitations. It is the case, for example, when one has to know precisely the thermal contact resistance or the nature of the signal sent. In this article is presented a characterization method based on thermal impedance formalism. This method allows for the determination of the thermal conductivity, the thermal diffusivity, and the contact thermal resistance in one single test. The application of this method requires the use of a specific probe developed to enable measurement of heat flux and temperature at the interface of the probe and the studied material. Its practical application is presented for dry sand.

  4. Anomalies in the Thermophysical Properties of Undercooled Glass-Forming Alloys

    Science.gov (United States)

    Hyers, Robert W.; Rogers, Jan R.; Kelton, Kenneth F.; Gangopadhyay, Anup

    2008-01-01

    The surface tension, viscosity, and density of several bulk metallic glass-forming alloys have been measured using noncontact techniques in the electrostatic levitation facility (ESL) at NASA Marshall Space Flight Center. All three properties show unexpected behavior in the undercooled regime. Similar deviations were previously observed in titanium-based quasicrystal-forming alloys,but the deviations in the properties of the glass-forming alloys are much more pronounced. New results for anomalous thermophysical properties in undercooled glass-forming alloys will be presented and discussed.

  5. Thermophysical Properties of Ammonium-Based Bis{(trifluoromethyl)sulfonyl}imide Ionic Liquids: Volumetric and Transport Properties

    Czech Academy of Sciences Publication Activity Database

    Machanová, Karolina; Boisset, A.; Sedláková, Zuzana; Anouti, M.; Bendová, Magdalena; Jacquemin, J.

    2012-01-01

    Roč. 57, č. 8 (2012), s. 2227-2235 ISSN 0021-9568. [European Conference on Thermophysical Properties /19./. Thessaloniki, 28.08.2011-01.09.2011] R&D Projects: GA ČR GP203/09/P141; GA MŠk(CZ) MEB021009 Grant - others:Égide PHC(FR) 22000XB Institutional support: RVO:67985858 Keywords : ionic liquids * density * transport properties Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.004, year: 2012

  6. Thermophysical properties of the Li(17)Pb(83) eutectic alloy

    International Nuclear Information System (INIS)

    Jauch, U.; Haase, G.; Schulz, B.

    1986-01-01

    Methods of measurements and results for the following properties of Li(17)Pb(83) are presented: density, specific heat, latent heat of fusion, surface energy, thermal conductivity and diffusivity, electrical conductivity and viscosity. The range of the temperature for extrapolation of the physical properties is discussed. (orig.)

  7. Thermophysical properties of two ammonium-based protic ionic liquids

    Science.gov (United States)

    Bhattacharjee, Arijit; Coutinho, João A. P.; Freire, Mara G.; Carvalho, Pedro J.

    2015-01-01

    Experimental data for density, viscosity, refractive index and surface tension are reported, for the first time, in the temperature range between 288.15 K and 353.15 K and at atmospheric pressure for two protic ionic liquids, namely 2-(dimethylamino)-N,N-dimethylethan-1-ammonium acetate, [N11{2(N11)}H][CH3CO2], and N-ethyl-N,N-dimethylammonium phenylacetate, [N112H][C7H7CO2]. The effect of the anion aromaticity and the cation’s aliphatic tails on the studied properties is discussed. From the measured properties temperature dependency the derived properties, such as the isobaric thermal expansion coefficient, the surface entropy and enthalpy, and the critical temperature, were estimated. PMID:26435554

  8. Thermophysical properties of simple liquid metals: A brief review of theory

    Science.gov (United States)

    Stroud, David

    1993-01-01

    In this paper, we review the current theory of the thermophysical properties of simple liquid metals. The emphasis is on thermodynamic properties, but we also briefly discuss the nonequilibrium properties of liquid metals. We begin by defining a 'simple liquid metal' as one in which the valence electrons interact only weakly with the ionic cores, so that the interaction can be treated by perturbation theory. We then write down the equilibrium Hamiltonian of a liquid metal as a sum of five terms: the bare ion-ion interaction, the electron-electron interaction, the bare electron-ion interaction, and the kinetic energies of electrons and ions. Since the electron-ion interaction can be treated by perturbation, the electronic part contributes in two ways to the Helmholtz free energy: it gives a density-dependent term which is independent of the arrangement of ions, and it acts to screen the ion-ion interaction, giving rise to effective ion-ion pair potentials which are density-dependent, in general. After sketching the form of a typical pair potential, we briefly enumerate some methods for calculating the ionic distribution function and hence the Helmholtz free energy of the liquid: monte Carlo simulations, molecular dynamics simulations, and thermodynamic perturbation theory. The final result is a general expression for the Helmholtz free energy of the liquid metal. It can be used to calculate a wide range of thermodynamic properties of simple metal liquids, which we enumerate. They include not only a range of thermodynamic coefficients of both metals and alloys, but also many aspects of the phase diagram, including freezing curves of pure elements and phase diagrams of liquid alloys (including liquidus and solidus curves). We briefly mention some key discoveries resulting from previous applications of this method, and point out that the same methods work for other materials not normally considered to be liquid metals (such as colloidal suspensions, in which the

  9. Thermo-physical properties of silica gel for adsorption desalination cycle

    KAUST Repository

    Thu, Kyaw

    2013-02-01

    Thermo-physical properties, surface characteristics and water vapor uptake capacity are key parameters in the selection of adsorbent for an adsorption desalination (AD) cycle. In the AD cycles, silica gel is used as adsorbent due to their high water vapor uptake capacity, reliability, repeatability and inexpensiveness as compared to other adsorbents. Three types of commercially available silica gels (Type-RD 2560,Type-A5BW and Type-A++) are investigated using a surface characteristic analyzer and their thermo-physical properties are evaluated using several analysis methods. The instrument used in this investigation employs the static volumetric method with liquid Nitrogen at 77 K as the filing fluid. The surface area of each adsorbent is studied using Brunauer-Emmett-Teller (BET) method whilst the pore size distribution (PSD) analysis is conducted with the Non-Local Density Functional Theory (NLDFT). It is observed that the Type-A++ silica gel (granular type) possesses the highest surface area of 863.6 m2/g amongst the three parent silica gels studied. It has a two-maxima or bimodal distribution pattern where the pore diameters are distributed mostly between 10 Å and 30 Å. Water vapor uptake capacity of silica gels are studied with water vapor dosage apparatus and the results show that the Type-A++ silica gel exhibits a highest equilibrium uptake at 537 cm3/g. These thermo-physical properties are essential for the design and the numerical simulation of AD cycles. © 2012 Published by Elsevier Ltd.

  10. Vapor pressures and thermophysical properties of selected monoterpenoids

    Czech Academy of Sciences Publication Activity Database

    Štejfa, V.; Dergal, F.; Mokbel, I.; Fulem, Michal; Jose, J.; Růžička, K.

    Roč. 406 , Nov (2015), 124-133 ISSN 0378-3812 Institutional support: RVO:68378271 Keywords : monoterpenoids * vapor pressure * heat capacity * ideal-gas thermodynamic properties * vaporization and sublimation enthalpy Subject RIV: BJ - Thermodynamics Impact factor: 1.846, year: 2015

  11. Use of genetic algorithm to identify thermophysical properties of deposited fouling in heat exchanger tubes

    International Nuclear Information System (INIS)

    Adili, Ali; Ben Salah, Mohieddine; Kerkeni, Chekib; Ben Nasrallah, Sassi

    2009-01-01

    At high temperature, the circulation of fluid in heat exchangers provides a tendency for fouling accumulation to take place on the internal surface of tubes. This paper shows an experimental process of thermophysical properties estimation of the fouling deposited on internal surface of a heat exchanger tube using genetic algorithms (GAs). The genetic algorithm is used to minimize an objective function containing calculated and measured temperatures. The experimental bench using a photothermal method with a finite width pulse heat excitation is used and the estimated parameters are obtained with high accuracy

  12. Science at Home: Measuring a Thermophysical Property of Water with a Microwave Oven

    Science.gov (United States)

    Levine, Zachary H.

    2018-02-01

    An attempt to calibrate a conventional oven led to making a measurement of a thermophysical property of water using items found in the author's home. Specifically, the ratio of the energy required to heat water from the melting point to boiling to the energy required to completely boil away the water is found to be 5.7. This may be compared to the standard value of 5.5. The close agreement is not representative of the actual uncertainties in this simple experiment (Fig. 1). Heating water in a microwave oven can let a student apply the techniques of quantitative science based on questions generated by his or her scientific curiosity.

  13. Thermophysical Properties of Nanoparticle-Enhanced Ionic Liquids (NEILs) Heat-Transfer Fluids

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Elise B.; Visser, Ann E.; Bridges, Nicholas J.; Amoroso, Jake W.

    2013-06-20

    An experimental investigation was completed on nanoparticle enhanced ionic liquid heat transfer fluids as an alternative to conventional organic based heat transfer fluids (HTFs). These nanoparticle-based HTFs have the potential to deliver higher thermal conductivity than the base fluid without a significant increase in viscosity at elevated temperatures. The effect of nanoparticle morphology and chemistry on thermophysical properties was examined. Whisker shaped nanomaterials were found to have the largest thermal conductivity temperature dependence and were also less likely to agglomerate in the base fluid than spherical shaped nanomaterials.

  14. Effect of thermophysical property and coating thickness on microstructure and characteristics of a casting

    Directory of Open Access Journals (Sweden)

    Ai-chao Cheng

    2017-01-01

    Full Text Available A new improved investment casting technology (IC has been presented and compared with the existing IC technology such as lost foam casting (LFC. The effect of thermophysical property and coating thickness on casting solidification temperature field, microstructure and hardness has been investigated. The results show that the solidification rate decreases inversely with the coating thickness when the coating contains silica sol, zircon powder, mullite powder and defoaming agent. In contrast, the solid cooling rate increases as the coating thickness increases. However, the solidification rate and solid cooling rate of the casting produced by the existing IC and the improved IC are very similar when the coating thickness is 5 mm, so the microstructure and hardness of a container corner fitting produced by the improved IC and the existing IC are similar. The linear regression equation for the grain size (d and cooling rate (v of the castings is d= –0.41v+206.1. The linear regression equation for the content of pearlite (w and solid cooling rate (t is w=1.79t + 6.71. The new improved IC can greatly simplify the process and decrease the cost of production compared with the existing IC. Contrasting with LFC, container corner fittings produced by the new improved IC have fewer defects and better properties. It was also found that the desired microstructure and properties can be obtained by changing the thermophysical property and thickness of the coating.

  15. SINGLE-PHASE AND TWO-PHASE SECONDARY COOLANTS: SIMULATION AND EVALUATION OF THEIR THERMOPHYSICAL PROPERTIES

    Directory of Open Access Journals (Sweden)

    Pedro Samuel Gomes Medeiros

    2011-09-01

    Full Text Available This paper makes a comparative analysis of the thermophysical properties of ice slurry with conventional single-phase secondary fluids used in thermal storage cooling systems. The ice slurry is a two-phase fluid consisting of water, antifreeze and ice crystals. It is a new technology that has shown great energy potential. In addition to transporting energy as a heat transfer fluid, it has thermal storage properties due to the presence of ice, storing coolness by latent heat of fusion. The single-phase fluids analyzed are water-NaCl and water-propylene glycol solutions, which also operate as carrier fluids in ice slurry. The presence of ice changes the thermophysical properties of aqueous solutions and a number of these properties were determined: density, thermal conductivity and dynamic viscosity. Data were obtained by software simulation. The results show that the presence of 10% by weight of ice provides a significant increase in thermal conductivity and dynamic viscosity, without causing changes in density. The rheological behavior of ice slurries, associated with its high viscosity, requires higher pumping power; however, this was not significant because higher thermal conductivity allows a lower mass flow rate without the use of larger pumps. Thus, the ice slurry ensures its high potential as a secondary fluid in thermal storage cooling systems, proving to be more efficient than single-phase secondary fluids.

  16. Metastability and thermophysical properties of metallic bulk glass forming alloys

    International Nuclear Information System (INIS)

    Wunderlich, R.K.; Fecht, H.J.

    1998-01-01

    The absence of crystallization over a wide time/temperature window can be used to produce bulk metallic glass by relatively slow cooling of the melt. For a number of alloys, including several multicomponent Zr-based alloys, the relevant thermodynamic and thermomechanical properties of the metastable glassy and undercooled liquid states have been measured below and above the glass transition temperature. These measurements include specific heat, viscosity, volume, and elastic properties as a function of temperature. As a result, it becomes obvious that the maximum undercooling for these alloys is given by an isentropic condition before an enthalpic or isochoric instability is reached. Alternatively, these glasses can also be produced by mechanical alloying, thus replacing the thermal disorder by static disorder and resulting in the same thermodynamic glass state. During heating through the undercooled liquid, a nanoscale phase separation occurs for most glasses as a precursor of crystallization

  17. Thermophysical properties of phosphonium-based ionic liquids

    Science.gov (United States)

    Bhattacharjee, Arijit; Lopes-da-Silva, José A.; Freire, Mara G.; Coutinho, João A. P.; Carvalho, Pedro J.

    2015-01-01

    Experimental data for density, viscosity, refractive index and surface tension of four phosphonium-based ionic liquids were measured in the temperature range between (288.15 and 353.15) K and at atmospheric pressure. The ionic liquids considered include tri(isobutyl) methylphosphonium tosylate, [Pi(444)1][Tos], tri(butyl)methylphosphonium methylsulfate, [P4441][CH3SO4], tri(butyl)ethylphosphonium diethylphosphate, [P4442][(C2H5O)2PO2], and tetraoctylphosphonium bromide, [P8888][Br]. Additionally, derivative properties, such as the isobaric thermal expansion coefficient, the surface thermodynamic properties and the critical temperatures for the investigated ionic liquids were also estimated and are presented and discussed. Group contribution methods were evaluated and fitted to the density, viscosity and refractive index experimental data. PMID:26435574

  18. Intermolecular potential energy surface and thermophysical properties of ethylene oxide

    International Nuclear Information System (INIS)

    Crusius, Johann-Philipp; Hassel, Egon; Hellmann, Robert; Bich, Eckard

    2014-01-01

    A six-dimensional potential energy hypersurface (PES) for two interacting rigid ethylene oxide (C 2 H 4 O) molecules was determined from high-level quantum-chemical ab initio calculations. The counterpoise-corrected supermolecular approach at the MP2 and CCSD(T) levels of theory was utilized to determine interaction energies for 10178 configurations of two molecules. An analytical site-site potential function with 19 sites per ethylene oxide molecule was fitted to the interaction energies and fine tuned to agree with data for the second acoustic virial coefficient from accurate speed of sound measurements. The PES was validated by computing the second virial coefficient, shear viscosity, and thermal conductivity. The values of these properties are substantiated by the best experimental data as they tend to fall within the uncertainty intervals and also obey the experimental temperature functions, except for viscosity, where experimental data are insufficient. Due to the lack of reliable data, especially for the transport properties, our calculated values are currently the most accurate estimates for these properties of ethylene oxide

  19. Intermolecular potential energy surface and thermophysical properties of ethylene oxide

    Energy Technology Data Exchange (ETDEWEB)

    Crusius, Johann-Philipp, E-mail: johann-philipp.crusius@uni-rostock.de; Hassel, Egon [Lehrstuhl für Technische Thermodynamik, Universität Rostock, 18059 Rostock (Germany); Hellmann, Robert; Bich, Eckard [Institut für Chemie, Universität Rostock, 18059 Rostock (Germany)

    2014-10-28

    A six-dimensional potential energy hypersurface (PES) for two interacting rigid ethylene oxide (C{sub 2}H{sub 4}O) molecules was determined from high-level quantum-chemical ab initio calculations. The counterpoise-corrected supermolecular approach at the MP2 and CCSD(T) levels of theory was utilized to determine interaction energies for 10178 configurations of two molecules. An analytical site-site potential function with 19 sites per ethylene oxide molecule was fitted to the interaction energies and fine tuned to agree with data for the second acoustic virial coefficient from accurate speed of sound measurements. The PES was validated by computing the second virial coefficient, shear viscosity, and thermal conductivity. The values of these properties are substantiated by the best experimental data as they tend to fall within the uncertainty intervals and also obey the experimental temperature functions, except for viscosity, where experimental data are insufficient. Due to the lack of reliable data, especially for the transport properties, our calculated values are currently the most accurate estimates for these properties of ethylene oxide.

  20. Thermophysical properties of freons methane series, pt.1

    CERN Document Server

    1987-01-01

    These are the succeeding volumes of a series of books on thermodynamic properties of engineering materials prepared under the auspices of the State Service of Standard Reference data of the Soviet Union. Each volume is set up in the same way: Part I deals with a study of all necessary aspects of experimental data interpretation and analysis; Part II then presents the fundamental constants, symbols with units, and data tables. Researchers and engineers in the fields of process design, equipment development, custody transfer and safety will find these book valuable and reliable reference sources for their respective tasks.

  1. Thermophysical Properties Measurement of High-Temperature Liquids Under Microgravity Conditions in Controlled Atmospheric Conditions

    Science.gov (United States)

    Watanabe, Masahito; Ozawa, Shumpei; Mizuno, Akotoshi; Hibiya, Taketoshi; Kawauchi, Hiroya; Murai, Kentaro; Takahashi, Suguru

    2012-01-01

    Microgravity conditions have advantages of measurement of surface tension and viscosity of metallic liquids by the oscillating drop method with an electromagnetic levitation (EML) device. Thus, we are preparing the experiments of thermophysical properties measurements using the Materials-Science Laboratories ElectroMagnetic-Levitator (MSL-EML) facilities in the international Space station (ISS). Recently, it has been identified that dependence of surface tension on oxygen partial pressure (Po2) must be considered for industrial application of surface tension values. Effect of Po2 on surface tension would apparently change viscosity from the damping oscillation model. Therefore, surface tension and viscosity must be measured simultaneously in the same atmospheric conditions. Moreover, effect of the electromagnetic force (EMF) on the surface oscillations must be clarified to obtain the ideal surface oscillation because the EMF works as the external force on the oscillating liquid droplets, so extensive EMF makes apparently the viscosity values large. In our group, using the parabolic flight levitation experimental facilities (PFLEX) the effect of Po2 and external EMF on surface oscillation of levitated liquid droplets was systematically investigated for the precise measurements of surface tension and viscosity of high temperature liquids for future ISS experiments. We performed the observation of surface oscillations of levitated liquid alloys using PFLEX on board flight experiments by Gulfstream II (G-II) airplane operated by DAS. These observations were performed under the controlled Po2 and also under the suitable EMF conditions. In these experiments, we obtained the density, the viscosity and the surface tension values of liquid Cu. From these results, we discuss about as same as reported data, and also obtained the difference of surface oscillations with the change of the EMF conditions.

  2. Effects of addition glycerol co-product of biodiesel in the thermophysical properties of water-glycerol solution applied as secondary coolant

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, Pedro Samuel Gomes; Barbosa, Cleiton Rubens Formiga; Fontes, Francisco de Assis Oliveira [Federal University of Rio Grande do Norte, Natal, RN (Brazil). Energy Laboratory. Thermal Systems Studies Group], e-mail: cleiton@ufrnet.br

    2010-07-01

    This paper evaluates the effects of glycerol concentration on thermophysical properties of water-glycerol solution applied as a secondary coolant in refrigeration systems by expansion-indirect. The processing of triglycerides for biodiesel production generates glycerol as co-product and there are concerns of environmental and economic order on the surplus of glycerol. The addition of glycerol in water alters the colligative and thermophysical properties (melting point, mass, specific heat, thermal conductivity and dynamic viscosity). There are studies that prove the feasibility of using glycerol as an additive and this paper has the goal to verify the changes on properties compared with pure water. This comparison was made from data obtained by the software simulation and they analyzed using graphs and tables. It was shown that glycerol increases the density and dynamic viscosity, and reduces the specific heat and thermal conductivity. This behavior of water-glycerol solution is proportional to the mass concentration of glycerol and it is justified because the glycerol has low values of specific heat, thermal conductivity and high viscosity when compared with water. Despite the losses in the thermophysical properties, glycerol shows its potential application, because of the cryoscopic effect and it is a non-toxic substance at low cost. (author)

  3. High-temperature thermophysical properties of γ - and δ -Mn from first principles

    Science.gov (United States)

    Ehteshami, Hossein; Ruban, Andrei V.

    2018-03-01

    Thermophysical properties of γ - and δ -Mn phases have been investigated using first-principles calculations in their thermodynamically stable temperature range. An adiabatic approximation is used for partitioning of the Helmholtz free energy into electronic, magnetic, and vibrational contributions from the corresponding temperature induced excitations, where the fastest degree of freedom has been included in the slower ones. Namely, electronic excitations (on a one-electron level) have been included directly in the first-principles calculations at the corresponding temperatures. Magnetic excitations in the paramagnetic state then have been taken into consideration in the two opposite limits: localized, considering only transverse spin fluctuations (TSF), and itinerant, allowing for the full coupling of transverse and longitudinal spin fluctuations (LSF). Magnetic contribution to the free energy has been included in the calculations of the vibrational one, which has been obtained within the Debye-Grüneisen model. The calculated thermophysical properties such as lattice constance, thermal lattice expansion, and heat capacity are in good agreement with available experimental data, especially in the case when the itinerant magnetic model is chosen. We also present our results for elastic properties at high temperatures.

  4. Thermophysical Properties of Five Industrial Steels in the Solid and Liquid Phase

    Science.gov (United States)

    Wilthan, B.; Schützenhöfer, W.; Pottlacher, G.

    2017-07-01

    The need for characterization of thermophysical properties of steel was addressed in the FFG-Bridge Project 810999 in cooperation with our partner from industry, Böhler Edelstahl GmbH & Co KG. To optimize numerical simulations of production processes such as plastic deformation or remelting, additional and more accurate thermophysical property data were necessary for the group of steels under investigation. With the fast ohmic pulse heating circuit system and a commercial high-temperature Differential Scanning Calorimeter at Graz University of Technology, we were able to measure the temperature-dependent specific electrical resistivity and specific enthalpy for a set of five high alloyed steels: E105, M314, M315, P800, and V320 from room temperature up into the liquid phase. The mechanical properties of those steels make sample preparation an additional challenge. The described experimental approach typically uses electrically conducting wire-shaped specimen with a melting point high enough for the implemented pyrometric temperature measurement. The samples investigated here are too brittle to be drawn as wires and could only be cut into rectangular specimen by Electrical Discharge Machining. Even for those samples all electrical signals and the temperature signal can be recorded with proper alignment of the pyrometer. For each material under investigation, a set of data including chemical composition, solidus and liquidus temperature, enthalpy, electrical resistivity, and thermal diffusivity as a function of temperature will be reported.

  5. Thermophysical properties of paramagnetic Fe from first principles

    Science.gov (United States)

    Ehteshami, Hossein; Korzhavyi, Pavel A.

    2017-12-01

    A computationally efficient, yet general, free-energy modeling scheme is developed based on first-principles calculations. Finite-temperature disorder associated with the fast (electronic and magnetic) degrees of freedom is directly included in the electronic structure calculations, whereas the vibrational free energy is evaluated by a proposed model that uses elastic constants to calculate average sound velocity of the quasiharmonic Debye model. The proposed scheme is tested by calculating the lattice parameter, heat capacity, and single-crystal elastic constants of α -, γ -, and δ -iron as functions of temperature in the range 1000-1800 K. The calculations accurately reproduce the well-established experimental data on thermal expansion and heat capacity of γ - and δ -iron. Electronic and magnetic excitations are shown to account for about 20% of the heat capacity for the two phases. Nonphonon contributions to thermal expansion are 12% and 10% for α - and δ -Fe and about 30% for γ -Fe. The elastic properties predicted by the model are in good agreement with those obtained in previous theoretical treatments of paramagnetic phases of iron, as well as with the bulk moduli derived from isothermal compressibility measurements [N. Tsujino et al., Earth Planet. Sci. Lett. 375, 244 (2013), 10.1016/j.epsl.2013.05.040]. Less agreement is found between theoretically calculated and experimentally derived single-crystal elastic constants of γ - and δ -iron.

  6. THERMAL AND THERMOPHYSICAL PROPERTIES OF EPOXY-SILICA NANOCOMPOSITES OF CATIONIC POLYMERIZATION

    Directory of Open Access Journals (Sweden)

    N. G. Leonova

    2017-09-01

    Full Text Available The polymer and composites were received using epoxy resin EPONEX 1510 – diglycidyl ether of dicyclohexylolpropane and 15 % solution of boron trifluoride in diethylene glycol. The silica particles were formed in situ via the sol-gel method using hydrolytic polycondensation of tetraethoxysilane. The silica sol was obtained in acetone as the organic solvent. Silica filler content in the composites varied from 0.5 to 3 wt%. The effect of the nanofiller on the thermophysical and thermal properties of the obtained polymers was studied. Thermophysical characteristics were determined by differential scanning calorimetry on a TA Instruments DSC Q2000 apparatus at a rate of heating of 20 °С/min in the temperature range from 5 to 190 °C. With the objective of decreasing the influence of the technological (kinetic and thermal prehistory of the sample on its thermophysical characteristics, the scanning was done twice. The glass transition temperature and heat capacity jump of the composite coatings based on epoxy-silica prepared by cationic polymerization were studied. It was established that with an increase of filler content the glass transition temperature of composites increases, and the value of the heat capacity jump remains almost unchanged. Parameters of thermostability of polymer and composites were determined by thermogravimetric analysis on a TA Instruments Q50 apparatus at a rate of heating of 20 °С/min in the temperature range from 20 to 1000 °C in an atmosphere of oxygen. The destruction process of epoxy-silica composites proceeds in several stages. In the deep stages of the thermo-oxidative destruction of obtained composites the effect of the silica filler is insignificant. The obtained polymer coatings were subjected to a long-term (100 hours isothermal aging at 160 °C in an atmosphere of oxygen. It was determined that the maximum rate of mass loss rate of epoxy-silica composites is 1.5 times lower than that of unmodified polymer.

  7. Prediction of thermophysical and transport properties of ternary organic non-electrolyte systems including water by polynomials

    Directory of Open Access Journals (Sweden)

    Đorđević Bojan D.

    2013-01-01

    Full Text Available The description and prediction of the thermophysical and transport properties of ternary organic non-electrolyte systems including water by the polynomial equations are reviewed. Empirical equations of Radojković et al. (also known as Redlich-Kister, Kohler, Jacob-Fitzner, Colinet, Tsao-Smith, Toop, Scatchard et al. and Rastogi et al. are compared with experimental data of available papers appeared in well know international journals (Fluid Phase Equilibria, Journal of Chemical and Engineering Data, Journal of Chemical Thermodynamics, Journal of Solution Chemistry, Journal of the Serbian Chemical Society, The Canadian Journal of Chemical Engineering, Journal of Molecular Liquids, Thermochimica Acta, etc.. The applicability of empirical models to estimate excess molar volumes, VE, excess viscosities, ηE, excess free energies of activation of a viscous flow,

  8. Experimental study of thermophysical properties and nanostructure of self-assembled water/polyalphaolefin nanoemulsion fluids

    Directory of Open Access Journals (Sweden)

    Jiajun Xu

    2015-04-01

    Full Text Available In this study, the nanostructures and thermophysical properties (thermal conductivity, viscosity, and specific heat of one new type of nanostructured heat transfer fluid, water/polyalphaolefin nanoemulsion fluid, are investigated. The water/polyalphaolefin nanoemulsion fluids are thermodynamically stable containing dispersed water nanodroplets formed by self-assembly. It has been found that the nanostructure inside nanoemulsion fluids may affect their thermophysical properties, especially the phase change heat transfer characteristics. The small-angle neutron scattering technique has been used to help identify the nanostructure inside the water/polyalphaolefin nanoemulsion fluids. By using the 3-region Guinier–Porod model, the fitting curve shows that there is a nonlinear variation of the nanodroplets’ size and shape with water’s concentration, which also coincides with the trend of its viscosity and specific heat. On the other hand, the thermal conductivity increases linearly with higher volume fraction of water which, however, appears to be insensitive to the nanostructure change. While the water nanodroplets inside can increase the thermal conductivity of the nanoemulsion fluid by 16%, its effective specific heat can be boosted up to 90% when the water nanodroplets undergo liquid–solid phase change.

  9. Enhancement of heat transfer coefficient multi-metallic nanofluid with ANFIS modeling for thermophysical properties

    Directory of Open Access Journals (Sweden)

    Balla Hyder H.

    2015-01-01

    Full Text Available Cu and Zn-water nanofluid is a suspension of the Cu and Zn nanoparticles with the size 50 nm in the water base fluid for different volume fractions to enhance its Thermophysical properties. The determination and measuring the enhancement of Thermophysical properties depends on many limitations. Nanoparticles were suspended in a base fluid to prepare a nanofluid. A coated transient hot wire apparatus was calibrated after the building of the all systems. The vibro-viscometer was used to measure the dynamic viscosity. The measured dynamic viscosity and thermal conductivity with all parameters affected on the measurements such as base fluids thermal conductivity, volume factions, and the temperatures of the base fluid were used as input to the Artificial Neural Fuzzy inference system to modeling both dynamic viscosity and thermal conductivity of the nanofluids. Then, the ANFIS modeling equations were used to calculate the enhancement in heat transfer coefficient using CFD software. The heat transfer coefficient was determined for flowing flow in a circular pipe at constant heat flux. It was found that the thermal conductivity of the nanofluid was highly affected by the volume fraction of nanoparticles. A comparison of the thermal conductivity ratio for different volume fractions was undertaken. The heat transfer coefficient of nanofluid was found to be higher than its base fluid. Comparisons of convective heat transfer coefficients for Cu and Zn nanofluids with the other correlation for the nanofluids heat transfer enhancement are presented. Moreover, the flow demonstrates anomalous enhancement in heat transfer nanofluids.

  10. Measurement of uranium dioxide thermophysical properties by the laser flash method

    International Nuclear Information System (INIS)

    Grossi, Pablo Andrade; Ferreira, Ricardo Alberto Neto; Camarano, Denise das Merces; Andrade, Roberto Marcio de

    2009-01-01

    The evaluation of the thermophysical properties of uranium dioxide (UO 2 ), including a reliable uncertainty assessment, are required by the nuclear reactor design. These important information are used by thermohydraulic codes to define operational aspects and to assure the safety, when analyzing various potential situations of accident. The laser flash method had become the most popular method to measure the thermophysical properties of materials. Despite its several advantages, some experimental obstacles have been found due to the difficulty to obtain experimentally the ideals initial and boundary conditions required by the original method. An experimental apparatus and a methodology for estimating uncertainties of thermal diffusivity, thermal conductivity and specific heat measurements based on the laser flash method are presented. A stochastic thermal diffusion modeling has been developed and validated by standard samples. Inverse heat conduction problems (IHCPs) solved by finite volumes technique were applied to the measurement process with real initial and boundary conditions, and Monte Carlo Method was used for propagating the uncertainties. The main sources of uncertainty were due to: pulse time, laser power, thermal exchanges, absorptivity, emissivity, sample thickness, specific mass and dynamic influence of temperature measurement system. As results, mean values and uncertainties of thermal diffusivity, thermal conductivity and specific heat of UO 2 are presented. (author)

  11. Effective moisture diffusivity, moisture sorption, thermo-physical properties and infrared drying kinetics of germinated paddy

    Directory of Open Access Journals (Sweden)

    Supawan Tirawanichakul

    2014-02-01

    Full Text Available Temperature and relative humidity (RH dependence of moisture sorption phenomena for agricultural products provide valuable information related to the thermodynamics of the system. So the equilibrium moisture contents (EMC, effective moisture diffusivity (Deff and thermo-physical properties in terms of void fraction, specific heat capacity, and the apparent density of germinated non-waxy Suphanburi 1 paddy were evaluated. Five commonly cited EMC equations were fitted to the experimental data among temperatures of 40-60°C correlating with RH of 0-90%. The results showed that the modified GAB equation was the best function for describing experimental results while those evaluated thermo-physical properties depended on moisture content. To determine drying kinetics model, the simulated values using Midilli et al. (2002 model and Page’s model was the best fitting to exact drying kinetics values for infrared (IR and hot air (HA drying, respectively. Finally, the Deff value of paddy dried with IR and HA sources were also evaluated and the calculated Deff value of both HA and IR drying was in order of 10-9 m2/s.

  12. Thermophysical properties of lignocellulose: a cell-scale study down to 41 K.

    Directory of Open Access Journals (Sweden)

    Zhe Cheng

    Full Text Available Thermal energy transport is of great importance in lignocellulose pyrolysis for biofuels. The thermophysical properties of lignocellulose significantly affect the overall properties of bio-composites and the related thermal transport. In this work, cell-scale lignocellulose (mono-layer plant cells is prepared to characterize their thermal properties from room temperature down to ∼ 40 K. The thermal conductivities of cell-scale lignocellulose along different directions show a little anisotropy due to the cell structure anisotropy. It is found that with temperature going down, the volumetric specific heat of the lignocellulose shows a slower decreasing trend against temperature than microcrystalline cellulose, and its value is always higher than that of microcrystalline cellulose. The thermal conductivity of lignocellulose decreases with temperature from 243 K to 317 K due to increasing phonon-phonon scatterings. From 41 K to 243 K, the thermal conductivity rises with temperature and its change mainly depends on the heat capacity's change.

  13. Selection of Prediction Methods for Thermophysical Properties for Process Modeling and Product Design of Biodiesel Manufacturing

    DEFF Research Database (Denmark)

    Su, Yung-Chieh; Liu, Y. A.; Díaz Tovar, Carlos Axel

    2011-01-01

    To optimize biodiesel manufacturing, many reported studies have built simulation models to quantify the relationship between operating conditions and process performance. For mass and energy balance simulations, it is essential to know the four fundamental thermophysical properties of the feed oil......: liquid density (ρL), vapor pressure (Pvap), liquid heat capacity (CPL), and heat of vaporization (ΔHvap). Additionally, to characterize the fuel qualities, it is critical to develop quantitative correlations to predict three biodiesel properties, namely, viscosity, cetane number, and flash point. Also......, to ensure the operability of biodiesel in cold weather, one needs to quantitatively predict three low-temperature flow properties: cloud point (CP), pour point (PP), and cold filter plugging point (CFPP). This article presents the results from a comprehensive evaluation of the methods for predicting...

  14. Measurements of thermophysical properties of urania-gadolinia pellets by the laser flash method

    Energy Technology Data Exchange (ETDEWEB)

    Mansur, Fabio A.; Camarano, Denise M.; Santos, Ana M.M.; Ferraz, Wilmar B.; Ribeiro, Luciana S.; Ferreira, Ricardo A.N.; Santos, Armindo, E-mail: fam@cdtn.br, E-mail: dmc@cdtn.br, E-mail: amms@cdtn.br, E-mail: ferrazw@cdtn.br, E-mail: lsr@cdtn.br, E-mail: ricardoanf@yahoo.com.br, E-mail: santosa@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-07-01

    The most common fuel used in pressurized water reactors is the uranium dioxide (UO{sub 2}). However, there are other modern conceptions of nuclear fuels that have advantages over UO{sub 2}. Gadolinium is used as a burnable poison which enables compensation of reactivity and the power distribution adjustment in the reactor core. The utilization of (U,Gd)O{sub 2} fuels instead of separate burnable poison rods is considered in pressurized water reactor for the purpose of extended fuel cycles and higher target burnups. The thermal conductivity of the fuel material is one of the most important properties to evaluate their thermal performance under irradiation. Pellets of (U,Gd)O{sub 2} were produced by uniaxial pressing microspheres and powder of UO{sub 2} mixed with 6w% of Gd{sub 2}O{sub 3} powder, as well as pressing microspheres of uranium and gadolinium mixed oxide (U,Gd)O{sub 2}, with concentrations of Gd ranging between 2w% and 10w%. The purpose of this study was to determine the thermophysical properties of these (U,Gd)O{sub 2} pellets and compare with the thermal conductivity of a pellet produced by pressing microspheres of UO{sub 2}, and taken as a reference, to investigate the effect of gadolinium oxide content on the thermal diffusivity and thermal conductivity of the fuel. The pellets thermophysical properties were measured at the LMPT - Laboratorio de Medicao de Propriedades Termofisicas de Combustiveis Nucleares e Materiais of CDTN - Centro de Desenvolvimento da Tecnologia Nuclear, applying the laser flash method. The thermophysical properties, density, specific heat, thermal diffusivity and thermal conductivity are reported. Values of thermal conductivity varying, in function of the gadolinium content, in the range from 5.57 W.m{sup -1}.K{sup -1} to 7.74 W.m{sup -1}, thermal diffusivity from 1.74x10{sup -6} m{sup 2}.s{sup -1} to 2.36x10{sup -6} m{sup 2}.s{sup -1}, and specific heat from 279.26 J.kg{sup -1}.K{sup -1} to 363.99 J.kg{sup -1}.K{sup -1}, were

  15. Study of structure and thermophysical properties of molten BaGe by using electrostatic levitation technique

    Science.gov (United States)

    Ishikura, Akiko; Masaki, Tadahiko; Ishikawa, Takehiko; Koike, Noriyuki; Kohara, Shinji; Mizuno, Akitoshi; Watanabe, Masahito

    2006-03-01

    BaGe alloys with two compositions around their eutectic point form open framework structures called clathrate structure. However, the formation mechanism of clathrate structure has not yet been clarified due to lack of study and understanding of their liquid state structure and properties. Therefore, in order to clarify the formation mechanism of the clathrate structure, thermophysical properties (density, surface tension, and viscosity) of BaGe alloys melts around eutectic compositions were measured by using the electrostatic levitation (ESL) technique and also the structure of them was observed by using the high-energy X-ray diffraction method combined with the ESL. We found that from experimental results, the short range order based on the clathrate structure would exist even in the liquid state at the clathrate forming compositions.

  16. Outline of experimental schemes for measurements of thermophysical and transport properties in warm dense matter at GSI and FAIR

    International Nuclear Information System (INIS)

    Tauschwitz, Anna; Jacoby, Joachim; Maruhn, Joachim; Basko, Mikhail; Efremov, Vladimir; Iosilevskiy, Igor; Neumayer, Paul; Novikov, Vladimir; Tauschwitz, Andreas; Rosmej, Frank

    2010-01-01

    Different experimental schemes for investigation of warm dense matter produced with intense energetic ion beams are presented. The described target configurations allow direct measurements of thermophysical and transport properties of warm dense matter without hydrodynamic recalculations. The presented experiments will be realized at the current GSI synchrotron SIS-18 and the future FAIR facility in the framework of the WDM-collaboration.

  17. Investigation of Thermophysical Parameters Properties for Enhancing Overpressure Mechanism Estimation. Case Study: Miri Area, West Baram Delta

    Science.gov (United States)

    Adha, Kurniawan; Yusoff, Wan Ismail Wan; Almanna Lubis, Luluan

    2017-10-01

    Determining the pore pressure data and overpressure zone is a compulsory part of oil and gas exploration in which the data can enhance the safety with profit and preventing the drilling hazards. Investigation of thermophysical parameters such as temperature and thermal conductivity can enhance the pore pressure estimation for overpressure mechanism determination. Since those parameters are dependent on rock properties, it may reflect the changes on the column of thermophysical parameters when there is abnormally in pore pressure. The study was conducted in “MRI 1” well offshore Sarawak, where a new approach method designed to determine the overpressure generation. The study was insisted the contribution of thermophysical parameters for supporting the velocity analysis method, petrophysical analysis were done in these studies. Four thermal facies were identified along the well. The overpressure developed below the thermal facies 4, where the pressure reached 38 Mpa and temperature was increasing significantly. The velocity and the thermal conductivity cross plots shows a linear relationship since the both parameters mainly are the function of the rock compaction. When the rock more compact, the particles were brought closer into contact and making the sound wave going faster while the thermal conductivity were increasing. In addition, the increment of temperature and high heat flow indicated the presence of fluid expansion mechanism. Since the shale sonic velocity and density analysis were the common methods in overpressure mechanism and pore pressure estimation. As the addition parameters for determining overpressure zone, the presence of thermophysical analysis was enhancing the current method, where the current method was the single function of velocity analysis. The presence of thermophysical analysis will improve the understanding in overpressure mechanism determination as the new input parameters. Thus, integrated of thermophysical technique and velocity

  18. Stability and thermophysical properties of non-covalently functionalized graphene nanoplatelets nanofluids

    International Nuclear Information System (INIS)

    Sarsam, Wail Sami; Amiri, Ahmad; Kazi, S.N.; Badarudin, A.

    2016-01-01

    Highlights: • The prepared water-based pristine GNPs nanofluids in this research were not stable. • All the surfactants investigated, SDBS, GA, CTAB, and SDS, increased the viscosity. • Thermal conductivity of nanofluids enhanced in the presence of GA, SDBS, and CTAB. • Highest nanofluid stability was obtained using an ultrasonication time of 60 min. • (1–1) SDBS–GNPs nanofluid with 60 min ultrasonication showed the highest stability. - Abstract: A pioneering idea for increasing the thermal performance of heat transfer fluids was to use ultrafine solid particles suspended in the base fluid. Nanofluids, synthesized by mixing solid nanometer sized particles at low concentrations with the base fluid, were used as a new heat transfer fluid and developed a remarkable effect on the thermophysical properties and heat transfer coefficient. For any nanofluid to be usable in heat transfer applications, the main concern is its long-term stability. The aim of this research is to investigate the effect of using four different surfactants (sodium dodecyl benzene sulfonate (SDBS), sodium dodecyl sulfate (SDS), cetyl trimethylammonium bromide (CTAB), and gum Arabic (GA)), each with three different concentrations, and five ultrasonication times (15, 30, 60, 90, and 120 min) on the stability of water-based graphene nanoplatelets (GNPs) nanofluids. In addition, the viscosity and thermal conductivity of the highest stability samples were measured at different temperatures. For this aim, nineteen different nanofluids with 0.1 wt% concentration of GNPs were prepared via the two-step method. An ultrasonication probe was utilized to disperse the GNPs in distilled water. UV–vis spectrometry, zeta potential, average particle size, and Transmission Electron Microscopy (TEM) were helpful in evaluating the stability and characterizing the prepared nanofluids. TEM and zeta potential results were in agreement with the UV–vis measurements. The highest nanofluid stability was

  19. Thermo-Physical Properties of Ammonium Azide under High Pressure from First-Principles

    Science.gov (United States)

    Landerville, Aaron; Steele, Brad; Oleynik, Ivan

    2013-03-01

    Polynitrogen compounds offer tremendous promise for use as insensitive high-explosives or propellants. While the existence of such compounds have been observed in Diamond Anvil Cells (DAC) under high pressure, recovery to ambient pressure and temperature has proven problematic. A current thrust towards the recovery, and ultimate manufacture, of materials rich in polymeric nitrogen has brought renewed attention to various nitrogen-rich compounds, particularly crystalline azides, as possible precursors. We investigate the thermo-physical properties and Raman spectra of one azide candidate - ammonium azide - under hydrostatic compression using density functional theory with an empirical van der Waals correction. Additionally, we perform structural minima searches to discern possible polymorphs that may help to elucidate dynamical processes leading to the production of a material rich in polymeric nitrogen, as well as its recovery from DAC.

  20. Effect of high hydrostatic pressure on rheological and thermophysical properties of murtilla (Ugni molinae Turcz) berries.

    Science.gov (United States)

    Lemus-Mondaca, Roberto; Ah-Hen, Kong; Vega-Gálvez, Antonio; Zura-Bravo, Liliana

    2016-06-01

    Effects of high hydrostatic pressure (HHP) on rheological and thermophysical properties of murtilla berries were evaluated after pressure treatments for 5 min between 100 and 500 MPa. Differential scanning calorimetry was employed to measure specific heat capacity. HHP caused a significant decrease in specific heat and density, while thermal diffusivity did not changed significantly. Thermal conductivity showed a slight increase upon HHP treatment. Apparent viscosity increased significantly above 200 MPa HHP treatment. Apparent viscosity of treated samples between 200 and 400 MPa did not differ significantly and the increase was significant at 500 MPa. Herschel-Bulkley, Bingham and Ostwald de Waele models were used to describe the rheological behaviour of murtilla purée, and Ostwald de Waele model gave the best fit for the experimental data.

  1. Thoria-based nuclear fuels thermophysical and thermodynamic properties, fabrication, reprocessing, and waste management

    CERN Document Server

    Bharadwaj, S R

    2013-01-01

    This book presents the state of the art on thermophysical and thermochemical properties, fabrication methodologies, irradiation behaviours, fuel reprocessing procedures, and aspects of waste management for oxide fuels in general and for thoria-based fuels in particular. The book covers all the essential features involved in the development of and working with nuclear technology. With the help of key databases, many of which were created by the authors, information is presented in the form of tables, figures, schematic diagrams and flow sheets, and photographs. This information will be useful for scientists and engineers working in the nuclear field, particularly for design and simulation, and for establishing the technology. One special feature is the inclusion of the latest information on thoria-based fuels, especially on the use of thorium in power generation, as it has less proliferation potential for nuclear weapons. Given its natural abundance, thorium offers a future alternative to uranium fuels in nuc...

  2. Thermophysical Properties Along Curiosity's Traverse in Gale Crater, Mars, Derived from the REMS Ground Temperature Sensor

    Science.gov (United States)

    Vasavada, Ashwin R.; Piqueux, Sylvain; Lewis, Kevin W.; Lemmon, Mark T.; Smith, Michael Doyle

    2016-01-01

    The REMS instrument onboard the Mars Science Laboratory rover, Curiosity, has measured ground temperature nearly continuously at hourly intervals for two Mars years. Coverage of the entire diurnal cycle at 1 Hz is available every few martian days. We compare these measurements with predictions of surface atmosphere thermal models to derive the apparent thermal inertia and thermally derived albedo along the rovers traverse after accounting for the radiative effects of atmospheric water ice during fall and winter, as is necessary to match the measured seasonal trend. The REMS measurements can distinguish between active sand, other loose materials, mudstone, and sandstone based on their thermophysical properties. However, the apparent thermal inertias of bedrock dominated surfaces [approx. 350-550 J m(exp. -2) K(exp. -1 s(exp. -1/2 )] are lower than expected. We use rover imagery and the detailed shape of the diurnal ground temperature curve to explore whether lateral or vertical heterogeneity in the surface materials within the sensor footprint might explain the low inertias. We find that the bedrock component of the surface can have a thermal inertia as high as 650-1700 J m(exp. -2) K(exp. -1) s(exp. -1/2) for mudstone sites and approx. 700 J m(exp. -2) K(exp. -1) s(exp. - 1/2) for sandstone sites in models runs that include lateral and vertical mixing. Although the results of our forward modeling approach may be non-unique, they demonstrate the potential to extract information about lateral and vertical variations in thermophysical properties from temporally resolved measurements of ground temperature.

  3. Experimental investigations of thermophysical properties of some paraffin waxes industrially manufactured in Poland

    Science.gov (United States)

    Zbińkowski, Piotr; Zmywaczyk, Janusz; Koniorczyk, Piotr

    2017-07-01

    Phase-change materials (PCM) can be applied as a heat absorbing/releasing medium in passive cooling systems. Such systems can be used in cooling and temperature stabilization of electronic components, i.e., Li-ion batteries, photovoltaic modules or light emitting diodes (LED). In order to optimize heat transfer in passive cooling systems experimental studies of PCM thermophysical properties are necessary. A good PCM candidate for passive cooling systems may be paraffin waxes due to their relatively high latent heat of fusion (L 200 J.g-1), suitable for working of electronic devices range of melting temperatures (22 °C - 68 °C) and a reasonable price. However, their main drawback is a relatively low thermal conductivity k ranging from 0.148 W.m-1.K-1 to 0.358 W.m-1.K-1. In this paper were presented results of experimentally determined temperature characteristics of thermophysical parameters of four paraffin waxes industrially manufactured in Jasło/Poland by POLWAX. The density ρ of the test paraffin waxes determined at room temperature (20 °C) using a laboratory balance RADWAG X/60/220 comprised from 0.82 g.cm-3 to 0.94 g.cm-3. The thermal diffusivity κ of paraffin waxes was tested within temperature range from -50 °C to 30 °C every 20 °C interval using the NETZSCH LFA 467 HyperFlash. The test specimens having form of cylinder were 12.7 mm in diameter and 2.15 - 2.20 mm in height. Prior to the experiment the face and the back surface of each specimen were coated with a thin layer of graphite 33 having a thickness of several micrometers in accordance with the recommendation given by NETZSCH. The thermal diffusivity of the test paraffin waxes within temperature interval -40 °C - 20 °C was determined to be 0.083 mm2.s-1 to 0.216 mm2.s-1. Thermal effects and the apparent heat capacity cp of the tested materials were measured in the temperature range from -10 °C to 100 °C using the NETZSCH DSC 404 F1 Pegasus at 10 K.min-1 heating/cooling rates in an

  4. Density functional investigation of the thermophysical and thermochemical properties of talc [Mg3Si4O10(OH)2

    Science.gov (United States)

    Ulian, Gianfranco; Valdrè, Giovanni

    2015-02-01

    The knowledge of the P, T behavior of talc is very important in mineralogical-petrological and geophysical research fields because talc can be considered a hydrous phase that can recycle water into the Earth's mantle and also an important mineral in both industrial and technological applications. However, very few works have been presented to fully characterize the thermodynamic properties of this mineral, especially at atomic scale. In a previous work, we modeled the structural and mechanical properties of talc using the B3LYP-D* hybrid density functional, which included a correction for the dispersive forces and all-electron Gaussian-type orbital basis sets. The results were in good agreement with single-crystal X-ray and neutron diffraction experimental data. Here, we extend the investigation to the thermochemical and thermophysical properties of talc using the same density functional approach and the quasi-harmonic approximation, providing the thermal equation of state, the heat capacity and the entropy of the mineral at different P, T conditions.

  5. New RELAP5-3D Lead and LBE Thermophysical Properties Implementation for Safety Analysis of Gen IV Reactors

    Directory of Open Access Journals (Sweden)

    P. Balestra

    2016-01-01

    Full Text Available The latest versions of RELAP5-3D© code allow the simulation of thermodynamic system, using different type of working fluids, that is, liquid metals, molten salt, diathermic oil, and so forth, thanks to the ATHENA code integration. The RELAP5-3D© water thermophysical properties are largely verified and validated; however there are not so many experiments to generate the liquid metals ones in particular for the Lead and the Lead Bismuth Eutectic. Recently, new and more accurate experimental data are available for liquid metals. The comparison between these state-of-the-art data and the RELAP5-3D© default thermophysical properties shows some discrepancy; therefore a tool for the generation of new properties binary files has been developed. All the available data came from experiments performed at atmospheric pressure. Therefore, to extend the pressure domain below and above this pressure, the tool fits a semiempirical model (soft sphere model with inverse-power-law potential, specific for the liquid metals. New binary files of thermophysical properties, with a detailed mesh grid of point to reduce the code mass error (especially for the Lead, were generated with this tool. Finally, calculations using a simple natural circulation loop were performed to understand the differences between the default and the new properties.

  6. Influence of condensed species on thermo-physical properties of LTE and non-LTE SF6-Cu mixture

    Science.gov (United States)

    Chen, Zhexin; Wu, Yi; Yang, Fei; Sun, Hao; Rong, Mingzhe; Wang, Chunlin

    2017-10-01

    SF6-Cu mixture is frequently formed in high-voltage circuit breakers due to the electrode erosion and metal vapor diffusion. During the interruption process, the multiphase effect and deviation from local thermal equilibrium (non-LTE assumption) can both affect the thermo-physical of the arc plasma and further influence the performance of circuit breaker. In this paper, thermo-physical properties, namely composition, thermodynamic properties and transport coefficients are calculated for multiphase SF6-Cu mixture with and without LTE assumption. The composition is confirmed by combining classical two-temperature mass action law with phase equilibrium condition deduced from second law of thermodynamics. The thermodynamic properties and transport coefficients are calculated using the multiphase composition result. The influence of condensed species on thermo-physical properties is discussed at different temperature, pressure (0.1-10 atm), non-equilibrium degrees (1-10), and copper molar proportions (0-50%). It is found that the multiphase effect has significant influence on specific enthalpy, specific heat and heavy species thermal conductivity in both LTE and non-LTE SF6-Cu system. This paper provides a more accurate database for computational fluid dynamic calculation.

  7. Thermo-physical stability of fatty acid eutectic mixtures subjected to accelerated aging for thermal energy storage (TES) application

    International Nuclear Information System (INIS)

    Fauzi, Hadi; Metselaar, Hendrik S.C.; Mahlia, T.M.I.; Silakhori, Mahyar

    2014-01-01

    The thermo-physical stability of fatty acids eutectic mixtures subjected to accelerated number of melting/solidification processes has been identified using thermal cycling test in this study. Myristic acid/palmitic acid (MA/PA) (70/30, wt.%) and myristic acid/palmitic acid/sodium stearate (MA/PA/SS) (70/30/5, wt.%) were selected as eutectic phase change materials (PCMs) to evaluate their stability of phase transition temperature, latent heat of fusion, chemical structure, and volume changes after 200, 500, 1000, and 1500 thermal cycles. The thermal properties of each eutectic PCMs measured by differential scanning calorimetric (DSC) indicated the phase transition temperature and latent heat of fusion values of MA/PA/SS has a smallest changes after 1500 thermal cycles than MA/PA eutectic mixture. MA/PA/SS also has a better chemical structure stability and smaller volume change which is 1.2%, compared to MA/PA with a volume change of 1.6% after 1500 cycles. Therefore, it is concluded that the MA/PA/SS eutectic mixture is suitable for use as a phase change material in thermal energy storage (TES) such as solar water heating and solar space heating applications. - Highlights: •The prepared MA/PA and MA/PA/SS were used as eutectic phase change materials (PCM). •Thermo-physical reliability of eutectic PCMs evaluated using a thermal cycling test. •MA/PA/SS has a great thermo-physical stability than MA/PA after 1500 thermal cycles

  8. Optimization of thermophysical properties of Pacific white shrimp (Litopenaeus vannamei) previously treated with freezing-point regulators using response surface methodology.

    Science.gov (United States)

    Wang, Liang; Liu, Zunying; Zhao, Yuanhui; Dong, Shiyuan; Zeng, Mingyong; Yang, Huicheng

    2015-08-01

    Three freezing-point regulators (glycine, sodium chloride and D-sorbitol) were employed to optimize thermophysical properties of Pacific white shrimp (Litopenaeus vannamei) using response surface methodology (RSM). The independent variables were glycine content (0.250-1.250 %), sodium chloride content (0.500-2.500 %) and D-sorbitol content (0.125-0.625 %) and analysis of variance showed that the effects of glycine, sodium chloride and D-sorbitol on the thermophysical properties were statistically significant (P freezing point (T i ), unfreezable water mass fraction (W u ), apparent specific heat (C app ) and Enthalpy (H) were 0.896 ~ 0.999. The combined effects of these independent variables on T i , W u , C app and H were investigated. The results indicated that T i , C app and H varied curvilinearly with increasing of glycine, sodium chloride and D-sorbitol content whereas W u increased nearly linearly. Based on response plots and desirability functions, the optimum combination of process variables for Pacific white shrimp previously treated with freezing-point regulators were 0.876 % for glycine content, 2.298 % for sodium chloride content and 0.589 % for D-sorbitol content, correspondently the optimized thermophysical properties were T i , - 5.086 °C; W u , 17.222 %; C app , 41.038 J/g °C and H, 155.942 J/g, respectively. Briefly, the application of freezing-point regulators depressed T i and obtained the optimum W u , C app and H, which would be obviously beneficial for the exploitation of various thermal processing and food storage.

  9. Side-by-side ANFIS as a useful tool for estimating correlated thermophysical properties

    Science.gov (United States)

    Grieu, Stéphane; Faugeroux, Olivier; Traoré, Adama; Claudet, Bernard; Bodnar, Jean-Luc

    2015-12-01

    In the present paper, an artificial intelligence-based approach dealing with the estimation of correlated thermophysical properties is designed and evaluated. This new and "intelligent" approach makes use of photothermal responses obtained when homogeneous materials are subjected to a light flux. Commonly, gradient-based algorithms are used as parameter estimation techniques. Unfortunately, such algorithms show instabilities leading to non-convergence in case of correlated properties to be estimated from a rebuilt impulse response. So, the main objective of the present work was to simultaneously estimate both the thermal diffusivity and conductivity of homogeneous materials, from front-face or rear-face photothermal responses to pseudo random binary signals. To this end, we used side-by-side neuro-fuzzy systems (adaptive network-based fuzzy inference systems) trained with a hybrid algorithm. We focused on the impact on generalization of both the examples used during training and the fuzzification process. In addition, computation time was a key point to consider. That is why the developed algorithm is computationally tractable and allows both the thermal diffusivity and conductivity of homogeneous materials to be simultaneously estimated with very good accuracy (the generalization error ranges between 4.6% and 6.2%).

  10. Performance dependence of thermosyphon on the functionalization approaches: An experimental study on thermo-physical properties of graphene nanoplatelet-based water nanofluids

    International Nuclear Information System (INIS)

    Amiri, Ahmad; Sadri, Rad; Shanbedi, Mehdi; Ahmadi, Goodarz; Chew, B.T.; Kazi, S.N.; Dahari, Mahidzal

    2015-01-01

    Highlights: • Highly dispersed GNP-based water nanofluids are prepared with the microwave-assisted method. • Rheological and thermo-physical properties of all treated samples are shown good enhancements. • Different heat transfer parameters are investigated in a thermosyphon. • An industrially scalable and cost-effective route is introduced. - Abstract: Graphene Nanoplatelets (GNP) were stably dispersed in aqueous media by covalent and non-covalent functionalization. Covalent functionalization was performed by a rapid microwave-assisted approach. Surface functionality groups and morphology of acid-treated GNP were analyzed by Fourier transform infrared spectroscopy and transmission electron microscopy. The GNP-based water nanofluids were then prepared with different concentrations of GNP to evaluate the thermo-physical and rheological properties. It was found that the rheological and thermo-physical properties of all treated samples were significantly enhanced compared to the pure water. The amount of enhancement also increased as the weight concentration increased. Thermo-physical results also confirmed that the thermal conductivity varied significantly depending on the functionalization approaches. At a constant concentration, the measurement showed that the thermal conductivity of covalent nanofluid (GNP-COOH/water) is larger than the non-covalent nanofluid (GNP-SDBS/water), which is larger than distilled water. The GNP-COOH/water nanofluids were found to be especially more effective in the thermosyphon in terms of overall thermal properties such as net heat transfer, entropy, and thermal efficiency, and rheological property such as effective viscosity, as well as, total pressure drop in comparison to GNP-SDBS/water nanofluids and certainly distilled water. The relative degradation of thermal conductivity and heat transfer efficiency of non-covalent nanofluids (GNP-SDBS/water) is due to the reduction of effective heat transfer surface of GNP

  11. Thermophysical properties of copper compounds in copper-chlorine thermochemical water splitting cycles

    International Nuclear Information System (INIS)

    Zamfirescu, C.; Dincer, I.; Naterer, G.F.

    2009-01-01

    This paper examines the relevant thermophysical properties of compounds of chlorine and copper that are found in thermochemical water splitting cycles. There are four variants of such Cu-Cl cycles that use heat and electricity to split the water molecule and produce H 2 and O 2 . Since the energy input is mainly in the form of thermal energy, the Cu-Cl water splitting cycle is much more efficient than water electrolysis, if the electricity generation efficiency for electrolysis is taken into account. A number of copper compounds (Cu 2 OCl 2 , CuO, CuCl 2 , CuCl) and other chemicals (Cu, HCl) are recycled within the plant, while the overall effect is splitting of the water molecule. The system includes a number of chemical reactors, heat exchangers, spray dryer and electrochemical cell. This paper identifies the available experimental data for properties of copper compounds relevant to the Cu-Cl cycle analysis and design. It also develops new regression formulas to correlate the properties, which include: specific heat, enthalpy, entropy, Gibbs free energy, density, formation enthalpy and free energy. No past literature data is available for the viscosity and thermal conductivity of molten CuCl, so estimates are provided. The properties are evaluated at 1 bar and a range of temperatures from ambient to 675-1000K, which are consistent with the operating conditions of the cycle. Updated calculations of chemical exergies are provided as follows: 21.08, 6.268, 82.474, and 75.0 kJ/mol for Cu 2 OCl 2 , CuO, CuCl 2 and CuCl, respectively. For molten CuCl, the estimated viscosity varies from 2.6 to 1.7mPa.s. (author)

  12. DETERMINATION OF THERMOPHYSICAL PROPERTIES OF FERMENTED WHEAT RAW MATERIALS IN THE STUDY OF PROCESSES OF HEAT- AND MASS TRANSFER

    Directory of Open Access Journals (Sweden)

    A. V. Pribytkov

    2014-01-01

    Full Text Available Summary. The article presents the results of a study of thermophysical properties of fermented wheat raw materials used are described in this experimental method, explained the behavior of graphic curves under different external conditions, given the opportunity to use the results. Possibilities of application of physical characteristics in the design of various designs dryers. Introduced the concept of the fermented wheat feedstock described the appearance of the product and the conditions for its receipt, showing the influence of temperature and moisture on the investigational product. Shows the design of the stand to determine the thermal characteristics of the fermented wheat raw materials using the method of transient thermal regime and describes how it works. Introduced empirical regression equation adequately describe thermal characteristics. Depending on the results of the study are the coefficients of thermal conductivity, specific heat, thermal diffusivity on the moisture content and temperature. The linear dependence shows that with increasing temperature and moisture content of the physical characteristics increase.

  13. Global Regolith Thermophysical Properties of the Moon From the Diviner Lunar Radiometer Experiment

    Science.gov (United States)

    Hayne, Paul O.; Bandfield, Joshua L.; Siegler, Matthew A.; Vasavada, Ashwin R.; Ghent, Rebecca R.; Williams, Jean-Pierre; Greenhagen, Benjamin T.; Aharonson, Oded; Elder, Catherine M.; Lucey, Paul G.; Paige, David A.

    2017-12-01

    We used infrared data from the Lunar Reconnaissance Orbiter (LRO) Diviner Lunar Radiometer Experiment to globally map thermophysical properties of the Moon's regolith fines layer. Thermal conductivity varies from 7.4 × 10-4 W m-1 K-1 at the surface to 3.4 × 10-3 W m-1 K-1 at depths of 1 m, given density values of 1,100 kg m-3 at the surface to 1,800 kg m-3 at 1 m depth. On average, the scale height of these profiles is 7 cm, corresponding to a thermal inertia of 55 ± 2 J m-2 K-1 s-1/2 at 273 K, relevant to the diurnally active near-surface layer, 4-7 cm. The temperature dependence of thermal conductivity and heat capacity leads to an 2 times diurnal variation in thermal inertia at the equator. On global scales, the regolith fines are remarkably uniform, implying rapid homogenization by impact gardening of this layer on timescales thermal inertia (> 100 J m-2 K-1 s-1/2) in the interiors and ejecta of Copernican-aged impact craters and lower thermal inertia (thermal inertia provide a potential tool for age dating craters of previously unknown age, complementary to the approach suggested by Ghent et al. (2014). Several anomalous regions are identified in the global 128 pixels per degree maps presented here, including a high-thermal inertia deposit near the antipode of Tycho crater.

  14. Effect of Interfacial Modifying on Thermo-physical Properties of SiCp/Cu Composites

    Directory of Open Access Journals (Sweden)

    LIU Meng

    2016-08-01

    Full Text Available SiCp/Cu composites were successfully fabricated by vacuum hot-pressing method. Molybdenum coating was deposited on the surface of silicon carbide by sol-gel method. The effects of the interfacial design on thermo-physical properties of SiCp/Cu composites were studied. The results indicate that:continuous and uniform MoO3 coating can be deposited on the surface of silicon carbide by peroxomolybdic acid sol-gel system, and the best processing parameters are as follows:SiC:MoO3=5:1(mass ratio, H2O2:C2H5OH=1:1(volume ratio, and surface pretreatment with acetone and hydrofluoric acid is good to the deposition and growth of MoO3 coating. After hydrogen reduction at 540℃ for 90min the MoO3 is changed into MoO2, and then hydrogen reduction at 940℃ for 90min the MoO2 is changed into Mo absolutely, and the Mo coating is continuous and uniform. SiCp/Cu composites prepared by vacuum hot-pressing method show a compact and uniform microstructure, and the thermal conductivity of the composites is increased obviously after the Mo coating interfacial modification, which can reach 214.16W·m-1·K-1 when the volume of silicon carbide is about 50%.

  15. Thermophysical properties of heat-treated U-7Mo/Al dispersion fuel

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Tae Won; Kim, Yeon Soo; Park, Jong Man; Lee, Kyu Hong; Kim, Sunghwan; Lee, Chong-Tak; Yang, Jae Ho; Oh, Jang Soo; Sohn, Dong-Seong

    2018-04-01

    In this study, the effects of interaction layer (IL) on thermophysical properties of U-7Mo/Al dispersion fuel were examined. Microstructural analyses revealed that ILs were formed uniformly on U-Mo particles during heating of U-7Mo/Al samples. The IL volume fraction was measured by applying image analysis methods. The uranium loadings of the samples were calculated based on the measured meat densities at 298 K. The density of the IL was estimated by using the measured density and IL volume fraction. Thermal diffusivity and heat capacity of the samples after the heat treatment were measured as a function of temperature and volume fractions of U-Mo and IL. The thermal conductivity of IL-formed U-7Mo/Al was derived by using the measured thermal diffusivity, heat capacity, and density. The thermal conductivity obtained in the present study was lower than that predicted by the modified Hashin–Shtrikman model due to the theoretical model’s inability to consider the thermal resistance at interfaces between the meat constituents.

  16. Thermophysical properties of hydrophobised lime plaster - Experimental analysis of moisture effect

    Science.gov (United States)

    Pavlíková, Milena; Pernicová, Radka; Pavlík, Zbyšek

    2016-07-01

    Lime plasters are the most popular finishing materials in renewal of historical buildings and culture monuments. Because of their limited durability, new materials and design solutions are investigated in order to improve plasters performance in harmful environmental conditions. For the practical use, the plasters mechanical resistivity and the compatibility with substrate are the most decisive material parameters. However, also plasters hygric and thermal parameters affecting the overall hygrothermal function of the renovated structures are of the particular importance. On this account, the effect of moisture content on the thermophysical properties of a newly designed lime plasters containing hydrophobic admixture is analysed in the paper. For the comparative purposes, the reference lime and cement-lime plasters are tested as well. Basic characterization of the tested materials is done using bulk density, matrix density, and porosity measurements. Thermal conductivity and volumetric heat capacity in the broad range of moisture content are experimentally accessed using a transient impulse method. The obtained data reveals the significant increase of the both studied thermal parameters with increasing moisture content and gives information on plasters behaviour in a highly humid environment and/or in the case of their possible direct contact with liquid water. The accessed material parameters will be stored in a material database, where can find use as an input data for computational modelling of coupled heat and moisture transport in this type of porous building materials.

  17. Intelligent sensor in control systems for objects with changing thermophysical properties

    Science.gov (United States)

    Belousov, O. A.; Muromtsev, D. Yu; Belyaev, M. P.

    2018-04-01

    The control of heat devices in a wide temperature range given thermophysical properties of an object is a topical issue. Optimal control systems of electric furnaces have to meet strict requirements in terms of accuracy of production procedures and efficiency of energy consumption. The fulfillment of these requirements is possible only if the dynamics model describing adequately the processes occurring in the furnaces is used to calculate the optimal control actions. One of the types of electric furnaces is the electric chamber furnace intended for heat treatment of various materials at temperatures from thousands of degrees Celsius and above. To solve the above-mentioned problem and to determine its place in the system of energy-efficient control of dynamic modes in the electric furnace, we propose the concept of an intelligent sensor and a method of synthesizing variables on sets of functioning states. The use of synthesis algorithms for optimal control in real time ensures the required accuracy when operating under different conditions and operating modes of the electric chamber furnace.

  18. Thermophysical properties of composite materials based on high-molecular compounds with fibrous filler between 10 and 400 K

    International Nuclear Information System (INIS)

    Vasiliev, L.L.; Domorod, L.S.; Tanaeva, S.A.

    1979-01-01

    The thermophysical properties of glass, carbon, and glass-carbon fibers are examined, and it is noted that the properties of glass fibers increase monotonically with increasing temperature. The behavior of carbon-fiber thermal diffusivity along and across the fibers is found to be anomalous, especially at temperatures between 50 and 200 K. Attention is given to the study of the properties of glass-carbon fibers on the basis of epoxy resin EDT-10 with modifying additives as well as of the filler composed of carbon and glass-fiber ropes in a temperature range of 10 to 400 K

  19. Compactation pressure influence on the thermophysical properties of uranium dioxide fuel pellets produced with kernels

    International Nuclear Information System (INIS)

    Ferreira, Ricardo Alberto Neto; Andrade, Antonio Santos; Miranda, Odair; Grossi, Pablo Andrade; Camarano, Denise das Merces; Migliorini, Fabricio Lima; Silva, Egonn Hendrigo Carvalho; Andrade, Roberto Marcio de

    2009-01-01

    Under compaction pressures ranging from 300 MPa up to 500 MPa, fuel pellets of uranium dioxide were manufactured by the pressing of kernels. These were produced by the sol-gel process developed in Germany by NUKEM for using in high temperature gas cooled reactors, which were absorbed, transferred and implanted at CDTN-Centro de Desenvolvimento da Tecnologia Nuclear. The sintering was performed at 1700 deg C for two hours under argon with 4% hydrogen atmosphere, resulting sintered densities ranging from 9.33 g·cm -3 up to 10.08 g·cm -3 , determined by the xylol penetration-immersion method. Using the flash laser method, the thermophysical properties of the pellets were determined and thermal diffusivity ranging from 2.58 x 10 -6 m 2 ·s -1 up to 2.78 x 10 -6 m 2 ·s -1 and thermal conductivity from 6.22 m -1 ·K -1 up to 7.24 W·m -1 ·K -1 , corresponding to a decreasing of the porosity from 14.88% to 8.05%. The methodology is described and the influence of the compaction pressure on the pellet properties is also analyzed. The thermal conductivity results of this study will be very valuable to a project in development at CDTN, in which uranium dioxide pellets will be produced by the pressing of kernels, with beryllium oxide filling the voids between the kernels in order to enhance the thermal conductivity of the fuel and consequently, the thermal performance of the fuel rod, as required in extended burnup conditions. They will be used as reference to compare and calculate the favorable increase of the thermal conductivity, caused by the addition of beryllium oxide. (author)

  20. Linking THEMIS Orbital Data to MSL GTS Measurements: The Thermophysical Properties of the Bagnold Dunes, Mars

    Science.gov (United States)

    Edwards, C. S.; Piqueux, S.; Hamilton, V. E.; Fergason, R. L.; Herkenhoff, K. E.; Vasavada, A. R.; Sacks, L. E.; Lewis, K. W.; Smith, M. D.

    2017-12-01

    The surface of Mars has been characterized using orbital thermal infrared observations from the time of the Mariner 9 and Viking missions. More recent observations from missions such as the Thermal Emission Spectrometer onboard the Mars Global Surveyor and the Thermal Emission Imaging System (THEMIS) instrument onboard the 2001 Mars Odyssey orbiter have continued to expand global coverage at progressively higher resolution. THEMIS has been producing 100 m/pixel thermal infrared data with nearly global coverage of the surface for >15 years and has enabled new investigations that successfully link outcrop-scale information to physical properties of the surface. However, significant discrepancies between morphologies and interpreted surface properties derived from orbital thermal measurements remain, requiring a robust link to direct surface measurements. Here, we compare the thermophysical properties and particle sizes derived from the Mars Science Laboratory (MSL) rover's Ground Temperature Sensor (GTS), to those derived orbitally from THEMIS, ultimately linking these measurements to ground truth particle sizes determined from Mars Hand Lens Imager (MAHLI) images. We focus on the relatively homogenous Bagnold dunes, specifically Namib dune, and in general find that all three datasets report consistent particle sizes for the Bagnold dunes ( 110-350 µm, and are within measurement and model uncertainties), indicating that particles sizes of homogeneous materials determined from thermal measurements are reliable. In addition, we assess several potentially significant effects that could influence the derived particle sizes, including: 1) fine-scale (cm-m scale) ripples, and 2) thin (mm-cm) layering of indurated/armored materials. To first order, we find that small scale ripples and thin layers do not significantly affect the determination of bulk thermal inertia determined from orbit. However, a layer of coarser/indurated material and/or fine-scale layering does change

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

    Science.gov (United States)

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

    2008-08-01

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

  2. Isothermal (vapour + liquid) equilibrium and thermophysical properties for (1-butyl-3-methylimidazolium iodide + 1-butanol) binary system

    International Nuclear Information System (INIS)

    Teodorescu, Mariana

    2015-01-01

    Highlights: • The (vapour + liquid) equilibrium has been investigated at T = (353.15, 363.15, 373.15) K. • The refractive index vs. composition was determined at T = (293.15, 298.15, 308.15) K. • The system presents S-shape abatement from ideality in terms of G E . • Refractive index deviations are positive and increase with increasing temperature. • Densities, surface tensions, dielectric permittivities have been predicted. - Abstract: Experimental isothermal (vapour + liquid) equilibrium (VLE) data are reported for the binary mixture containing 1-butyl-3-methylimidazolium iodide ([bmim]I) + 1-butanol at three temperatures: (353.15, 363.15, and 373.15) K, in the range of 0 to 0.22 liquid mole fraction of [bmim]I. Additionally, refractive index measurements have been performed at three temperatures: (293.15, 298.15 and 308.15) K in the whole composition range. Densities, excess molar volumes, surface tensions and surface tension deviations of the binary mixture were predicted by Lorenz–Lorentz (n D -ρ) mixing rule. Dielectric permittivities and their deviations were evaluated by known equations. (Vapour + liquid) equilibrium data were correlated with Wilson thermodynamic model while refractive index data with the 3-parameters Redlich–Kister equation by means of maximum likelihood method. For the VLE data, the real vapour phase behaviour by virial equation of state was considered. The studied mixture presents S-shaped abatement from the ideality. Refractive index deviations, surface tension deviations and dielectric permittivity deviations are positive, while excess molar volumes are negative at all temperatures and on whole composition range. The VLE data may be used in separation processes design, and the thermophysical properties as key parameters in specific applications

  3. Influence of innovative technologies on rheological and thermophysical properties of whey proteins and guar gum model systems

    Directory of Open Access Journals (Sweden)

    Greta Krešić

    2011-03-01

    Full Text Available The aim of this study was to examine the effect of high-power ultrasound (US and highpressure processing (HP on model systems composed of whey protein concentrate (WPC and whey protein isolate (WPI with or without guar gum addition. This kind of systems can be found in food production industry so the aim was to use novel food processing technologies to be utilized as a method for products development. Aqueous suspensions (10 g kg-1 of powdered whey proteins were treated with either ultrasound or high pressure. The treatment conditions were as follows: US: frequency of 30 kHz, for 5 and 10 min; HP: pressure intensity 300-600 MPa, for 5 and 10 min. Rheological and thermophysical properties were analyzed after guar gum addition (0.5 g kg-1. Ultrasound treatment showed a significant influence on all examined properties through protein denaturation caused by cavitation and microstreaming effects. High pressure caused significant increase in viscosity and consistency coefficients of model systems with and without guar addition. Significant decrease of initial freezing and initial thawing temperature was observed in all samples. With this research the direct influence of ultrasound and high-pressure treatment on the rheological and thermophysical properties of whey protein isolate and concentrate model systems with or without guar gum was demonstrated.

  4. SHERMAN - A shape-based thermophysical model II. Application to 8567 (1996 HW1)

    Science.gov (United States)

    Howell, E. S.; Magri, C.; Vervack, , R. J.; Nolan, M. C.; Taylor, P. A.; Fernández, Y. R.; Hicks, M. D.; Somers, J. M.; Lawrence, K. J.; Rivkin, A. S.; Marshall, S. E.; Crowell, J. L.

    2018-03-01

    We apply a new shape-based thermophysical model, SHERMAN, to the near-Earth asteroid (NEA) 8567 (1996 HW1) to derive surface properties. We use the detailed shape model of Magri et al. (2011) for this contact binary NEA to analyze spectral observations (2-4.1 microns) obtained at the NASA IRTF on several different dates to find thermal parameters that match all the data. Visible and near-infrared (0.8-2.5 microns) spectral observations are also utilized in a self-consistent way. We find that an average visible albedo of 0.33, thermal inertia of 70 (SI units) and surface roughness of 50% closely match the observations. The shape and orientation of the asteroid is very important to constrain the thermal parameters to be consistent with all the observations. Multiple viewing geometries are equally important to achieve a robust solution for small, non-spherical NEAs. We separate the infrared beaming effects of shape, viewing geometry and surface roughness for this asteroid and show how their effects combine. We compare the diameter and albedo that would be derived from the thermal observations assuming a spherical shape with those from the shape-based model. We also discuss how observations from limited viewing geometries compare to the solution from multiple observations. The size that would be derived from the individual observation dates varies by 20% from the best-fit solution, and can be either larger or smaller. If the surface properties are not homogeneous, many solutions are possible, but the average properties derived here are very tightly constrained by the multiple observations, and give important insights into the nature of small NEAs.

  5. Development of Ultrafast Laser Flash Methods for Measuring Thermophysical Properties of Thin Films and Boundary Thermal Resistances

    Science.gov (United States)

    Baba, Tetsuya; Taketoshi, Naoyuki; Yagi, Takashi

    2011-11-01

    Reliable thermophysical property values of thin films are important to develop advanced industrial technologies such as highly integrated electronic devices, phase-change memories, magneto-optical disks, light-emitting diodes (LEDs), organic light-emitting diodes (OLEDs), semiconductor lasers (LDs), flat-panel displays, and power electronic devices. In order to meet these requirements, the National Metrology Institute of Japan of the National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) has developed ultrafast laser flash methods heated by picosecond pulse or nanosecond pulse with the same geometrical configuration as the laser flash method, which is the standard method to measure the thermal diffusivity of bulk materials. Since these pulsed light heating methods induce one-dimensional heat diffusion across a well-defined length of the specimen thickness, the absolute value of thermal diffusivity across thin films can be measured reliably. Using these ultrafast laser flash methods, the thermal diffusivity of each layer of multilayered thin films and the boundary thermal resistance between the layers can be determined from the observed transient temperature curves based on the response function method. The thermophysical properties of various thin films important for modern industries such as the transparent conductive films used for flat-panel displays, hard coating films, and multilayered films of next-generation phase-change optical disks have been measured by these methods.

  6. Thermophysical properties database of materials for light water reactors and heavy water reactors. Final report of a coordinated research project 1999-2005

    International Nuclear Information System (INIS)

    2006-06-01

    The IAEA Coordinated Research Project (CRP) on the Establishment of a Thermo-physical Properties Database for Light Water Reactors (LWRs) and Heavy Water Reactors (HWRs) started in 1999. It was included in the IAEA's Nuclear Power Programme following endorsement in 1997 by the IAEA's Technical Working Groups on Advanced Technologies for LWRs and HWRs (the TWG-LWR and the TWG-HWR). Furthermore, the TWG on Fuel Performance and Technology (TWG-FPT) also expressed its support. This CRP was conducted as a joint task within the IAEA's project on technology development for LWRs and HWRs in its nuclear power programme. Improving the technology for nuclear reactors through better computer codes and more accurate materials property data can contribute to improved economics of future plants by helping to remove the need for large design margins, which are currently used to account for limitations of data and methods. Accurate representations of thermo-physical properties under relevant temperature and neutron fluence conditions are necessary for evaluating reactor performance under normal operation and accident conditions. The objective of this CRP was to collect and systematize a thermo-physical properties database for light and heavy water reactor materials under normal operating, transient and accident conditions and to foster the exchange of non-proprietary information on thermo-physical properties of LWR and HWR materials. An internationally available, peer reviewed database of properties at normal and severe accident conditions has been established on the Internet. This report is intended to serve as a useful source of information on thermo-physical properties data for water cooled reactor analyses. The properties data have been initially stored in the THERSYST data system at the University of Stuttgart, Germany, which was subsequently developed into an internationally available Internet database named THERPRO at Hanyang University, Republic of Korea

  7. Thermo-physical Properties and Mechanical Properties of Burn-resistant Titanium Alloy Ti40

    Directory of Open Access Journals (Sweden)

    LAI Yunjin

    2017-10-01

    Full Text Available As a functional material of burn-resistant titanium alloy, the physical properties of Ti40 alloy were first reported. The chemical compositions of Ti40 alloy ingots by VAR were uniform. The microstructures of Ti40 alloy slab manufactured by HEFF+WPF were uniform. The results show that the room temperature tensile strength of Ti40 alloy is 950 MPa degree. The properties of high temperature heat exposure, creep resistance and lasting time are good at 500 ℃. In the range from room temperature to 600 ℃, Young's modulus and shear modulus are decreased linearly with increasing the temperature, Poisson's ratio is increases slowly as the temperature rises, and linear thermal expansion coefficient and average linear expansion coefficient is increase as the temperature rises.

  8. Study of coherent structures of turbulence with large wall-normal gradients in thermophysical properties using direct numerical simulation

    Science.gov (United States)

    Reinink, Shawn K.; Yaras, Metin I.

    2015-06-01

    Forced-convection heat transfer in a heated working fluid at a thermodynamic state near its pseudocritical point is poorly predicted by correlations calibrated with data at subcritical temperatures and pressures. This is suggested to be primarily due to the influence of large wall-normal thermophysical property gradients that develop in proximity of the pseudocritical point on the concentration of coherent turbulence structures near the wall. The physical mechanisms dominating this influence remain poorly understood. In the present study, direct numerical simulation is used to study the development of coherent vortical structures within a turbulent spot under the influence of large wall-normal property gradients. A turbulent spot rather than a fully turbulent boundary layer is used for the study, for the coherent structures of turbulence in a spot tend to be in a more organized state which may allow for more effective identification of cause-and-effect relationships. Large wall-normal gradients in thermophysical properties are created by heating the working fluid which is near the pseudocritical thermodynamic state. It is found that during improved heat transfer, wall-normal gradients in density accelerate the growth of the Kelvin-Helmholtz instability mechanism in the shear layer enveloping low-speed streaks, causing it to roll up into hairpin vortices at a faster rate. It is suggested that this occurs by the baroclinic vorticity generation mechanism which accelerates the streamwise grouping of vorticity during shear layer roll-up. The increased roll-up frequency leads to reduced streamwise spacing between hairpin vortices in wave packets. The density gradients also promote the sinuous instability mode in low-speed streaks. The resulting oscillations in the streaks in the streamwise-spanwise plane lead to locally reduced spanwise spacing between hairpin vortices forming over adjacent low-speed streaks. The reduction in streamwise and spanwise spacing between

  9. Study of coherent structures of turbulence with large wall-normal gradients in thermophysical properties using direct numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Reinink, Shawn K.; Yaras, Metin I., E-mail: Metin.Yaras@carleton.ca [Department of Mechanical and Aerospace Engineering, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)

    2015-06-15

    Forced-convection heat transfer in a heated working fluid at a thermodynamic state near its pseudocritical point is poorly predicted by correlations calibrated with data at subcritical temperatures and pressures. This is suggested to be primarily due to the influence of large wall-normal thermophysical property gradients that develop in proximity of the pseudocritical point on the concentration of coherent turbulence structures near the wall. The physical mechanisms dominating this influence remain poorly understood. In the present study, direct numerical simulation is used to study the development of coherent vortical structures within a turbulent spot under the influence of large wall-normal property gradients. A turbulent spot rather than a fully turbulent boundary layer is used for the study, for the coherent structures of turbulence in a spot tend to be in a more organized state which may allow for more effective identification of cause-and-effect relationships. Large wall-normal gradients in thermophysical properties are created by heating the working fluid which is near the pseudocritical thermodynamic state. It is found that during improved heat transfer, wall-normal gradients in density accelerate the growth of the Kelvin-Helmholtz instability mechanism in the shear layer enveloping low-speed streaks, causing it to roll up into hairpin vortices at a faster rate. It is suggested that this occurs by the baroclinic vorticity generation mechanism which accelerates the streamwise grouping of vorticity during shear layer roll-up. The increased roll-up frequency leads to reduced streamwise spacing between hairpin vortices in wave packets. The density gradients also promote the sinuous instability mode in low-speed streaks. The resulting oscillations in the streaks in the streamwise-spanwise plane lead to locally reduced spanwise spacing between hairpin vortices forming over adjacent low-speed streaks. The reduction in streamwise and spanwise spacing between

  10. Thermophysical Properties of Matter - The TPRC Data Series. Volume 8. Thermal Radiative Properties - Nonmetallic Solids

    Science.gov (United States)

    1972-01-01

    34Radiation and Heat Transfer in Light Scattering Materials." Philips Research Repts.. i. 55 67. 103 II. 112 25,420 5, 1947. 53. Harrison. T. R...AsiSej, (AsxSb1_x)jSej, and Sl^Sj," J. Opt. Soc. Am., 58(3), 373-7, 1968. Keller, S. P. and Pettit , G. D., "Some Optical Properties of CdSe Single...Devices Made from Rare Earth Semiconductors," Final Rept., 1 Jan. - 31 Dec. 1961, AD 274 744, 1-86, 1961. Axe, J.D. and Pettit , G.D., "Infrared

  11. Modelling Behaviour of a Carbon Epoxy Composite Exposed to Fire: Part I-Characterisation of Thermophysical Properties.

    Science.gov (United States)

    Tranchard, Pauline; Samyn, Fabienne; Duquesne, Sophie; Estèbe, Bruno; Bourbigot, Serge

    2017-05-04

    Thermophysical properties of a carbon-reinforced epoxy composite laminate (T700/M21 composite for aircraft structures) were evaluated using different innovative characterisation methods. Thermogravimetric Analysis (TGA), Simultaneous Thermal analysis (STA), Laser Flash analysis (LFA), and Fourier Transform Infrared (FTIR) analysis were used for measuring the thermal decomposition, the specific heat capacity, the anisotropic thermal conductivity of the composite, the heats of decomposition and the specific heat capacity of released gases. It permits to get input data to feed a three-dimensional (3D) model given the temperature profile and the mass loss obtained during well-defined fire scenarios (model presented in Part II of this paper). The measurements were optimised to get accurate data. The data also permit to create a public database on an aeronautical carbon fibre/epoxy composite for fire safety engineering.

  12. Modelling Behaviour of a Carbon Epoxy Composite Exposed to Fire: Part I—Characterisation of Thermophysical Properties

    Science.gov (United States)

    Tranchard, Pauline; Samyn, Fabienne; Duquesne, Sophie; Estèbe, Bruno; Bourbigot, Serge

    2017-01-01

    Thermophysical properties of a carbon-reinforced epoxy composite laminate (T700/M21 composite for aircraft structures) were evaluated using different innovative characterisation methods. Thermogravimetric Analysis (TGA), Simultaneous Thermal analysis (STA), Laser Flash analysis (LFA), and Fourier Transform Infrared (FTIR) analysis were used for measuring the thermal decomposition, the specific heat capacity, the anisotropic thermal conductivity of the composite, the heats of decomposition and the specific heat capacity of released gases. It permits to get input data to feed a three-dimensional (3D) model given the temperature profile and the mass loss obtained during well-defined fire scenarios (model presented in Part II of this paper). The measurements were optimised to get accurate data. The data also permit to create a public database on an aeronautical carbon fibre/epoxy composite for fire safety engineering. PMID:28772854

  13. Modelling Behaviour of a Carbon Epoxy Composite Exposed to Fire: Part I—Characterisation of Thermophysical Properties

    Directory of Open Access Journals (Sweden)

    Pauline Tranchard

    2017-05-01

    Full Text Available Thermophysical properties of a carbon-reinforced epoxy composite laminate (T700/M21 composite for aircraft structures were evaluated using different innovative characterisation methods. Thermogravimetric Analysis (TGA, Simultaneous Thermal analysis (STA, Laser Flash analysis (LFA, and Fourier Transform Infrared (FTIR analysis were used for measuring the thermal decomposition, the specific heat capacity, the anisotropic thermal conductivity of the composite, the heats of decomposition and the specific heat capacity of released gases. It permits to get input data to feed a three-dimensional (3D model given the temperature profile and the mass loss obtained during well-defined fire scenarios (model presented in Part II of this paper. The measurements were optimised to get accurate data. The data also permit to create a public database on an aeronautical carbon fibre/epoxy composite for fire safety engineering.

  14. Estimation of the thermophysical and mechanical properties and the equation of state of Li2O. Revision 1

    International Nuclear Information System (INIS)

    Krikorian, O.H.

    1984-12-01

    In this study we develop correlation methods based on Knoop microhardness and melting points for estimating tensile strength, Young's modulus, and Poisson's ratio for Li 2 O as a function of grain size, porosity, and temperature. We develop generalized expressions for extrapolating the existing data on thermal conductivity and thermal expansivity. These derived thermophysical data are combined to predict thermal stress factors for Li 2 O. Based on the available vapor pressure data on Li 2 O and empirical correlations for the liquid and vapor equation of state of Li 2 O, we also make estimates of the critical properties of Li 2 O and obtain a critical temperature of approximately 6800 +- 800 0 K

  15. Thermophysical and Electronic Properties Information Analysis Center (TEPIAC): A Continuing Systematic Program on Tables of Thermophysical and Electronic Properties of Materials.

    Science.gov (United States)

    1977-02-01

    64 , 647 Polymers, rubbers , etc. 3,047 Ther mal radiative propertie s 38 , 534 Refrac tories 1,977 Mass diffusivity (to 1972) 28 , 780 Glasses 1,900...mixtures , borldes , bromides , carbides, chlorides , fluorides , nitrate s, nitrides , phosphates , sul- fates , sulfides , ce rmets , minerals and...state. These are cadm ium, chromium , lead , magnesium, molybdenum, nickel , niobium, tantalum, tin , titanium, zinc , zirconium , Acheson graphite

  16. Ab initio calculation of the interaction potentials of helium, neon, and methane as well as theoretical studies on their thermophysical properties and those of water vapor

    International Nuclear Information System (INIS)

    Hellmann, Robert

    2009-01-01

    Thermophysical properties of the pure gases helium, neon, methane and water vapor were calculated for low densities over wide temperature ranges. Statistical thermodynamics was used for the determination of the pressure virial coefficients. The kinetic theory of gases was utilized for the calculation of the transport and relaxation properties. So far kinetic theory was limited to linear molecules and has now been extended to molecules of arbitrary geometry to enable calculations on methane and water vapor. The interaction potentials, which are needed for all computations, were determined for helium, neon and methane from the supermolecular approach using quantum chemical ab initio methods. For water the interaction potentials were taken from the literature. The calculated values of the thermophysical properties for the four gases show very good agreement with the best experimental data. At very low and very high temperatures the theoretical values are more accurate than experimental data. (orig.)

  17. A comprehensive review of thermo-physical properties and convective heat transfer to nanofluids

    International Nuclear Information System (INIS)

    Solangi, K.H.; Kazi, S.N.; Luhur, M.R.; Badarudin, A.; Amiri, A.; Sadri, Rad; Zubir, M.N.M.; Gharehkhani, Samira; Teng, K.H.

    2015-01-01

    Nanofluids are fluid nanoparticle suspensions that exhibit enhanced properties at modest nanoparticle concentrations. Nanofluids have unique heat transfer properties and are utilized in high heat flux systems (e.g., electronic cooling systems, heat exchanger liquids, solar collectors, and nuclear reactors). However, suspension stability is critical in the development and application of these heat transfer fluids. Reynolds number, mass concentration, and particle size control the heat transfer behavior of fluids. Sedimentation and agglomeration of nanoparticles in nanofluids and their dispersion have rarely been investigated. Therefore, this paper explains the parameters that affect the stability of nanofluids and the different techniques used to evaluate the stability of nanofluids. This paper also presents an updated review of properties of nanofluids, such as physical (thermal conductivity) and rheological properties, with emphasis on their heat transfer enhancement characteristics. Studies on zeta potential as a function of pH are discussed and extended further to identify opportunities for future research. - Highlights: • Comprehensive review of nanofluids and latest methods of preparation. • Parameters that affect the stability of nanofluids and the different techniques are discussed. • Effect of different surfactants on the rheological properties of nanofluids has been presented. • Sedimentation and agglomeration of nanoparticles in nanofluids are discussed in detail. • zeta potential as a function of pH is discussed and opportunities for future research

  18. Thermophysical behavior of St. Peter sandstone: application to compressed air energy storage in an aquifer

    Energy Technology Data Exchange (ETDEWEB)

    Erikson, R.L.

    1983-12-01

    The long-term stability of a sandstone reservoir is of primary importance to the success of compressed air energy storage (CAES) in aquifers. The purpose of this study was to: develop experimental techniques for the operation of the CAES Porous Media Flow Loop (PMFL), an apparatus designed to study the stability of porous media in subsurface geologic environments, conduct experiments in the PMFL designed to determine the effects of temperature, stress, and humidity on the stability of candidate CAES reservoir materials, provide support for the CAES field demonstration project in Pittsfield, Illinois, by characterizing the thermophysical stability of Pittsfield reservoir sandstone under simulated field conditions.

  19. Influence of condensed species on thermo-physical properties of LTE and non-LTE SF6–Cu mixture

    International Nuclear Information System (INIS)

    Chen, Zhexin; Wu, Yi; Yang, Fei; Sun, Hao; Rong, Mingzhe; Wang, Chunlin

    2017-01-01

    SF 6 –Cu mixture is frequently formed in high-voltage circuit breakers due to the electrode erosion and metal vapor diffusion. During the interruption process, the multiphase effect and deviation from local thermal equilibrium (non-LTE assumption) can both affect the thermo-physical of the arc plasma and further influence the performance of circuit breaker. In this paper, thermo-physical properties, namely composition, thermodynamic properties and transport coefficients are calculated for multiphase SF 6 –Cu mixture with and without LTE assumption. The composition is confirmed by combining classical two-temperature mass action law with phase equilibrium condition deduced from second law of thermodynamics. The thermodynamic properties and transport coefficients are calculated using the multiphase composition result. The influence of condensed species on thermo-physical properties is discussed at different temperature, pressure (0.1–10 atm), non-equilibrium degrees (1–10), and copper molar proportions (0–50%). It is found that the multiphase effect has significant influence on specific enthalpy, specific heat and heavy species thermal conductivity in both LTE and non-LTE SF 6 –Cu system. This paper provides a more accurate database for computational fluid dynamic calculation. (paper)

  20. On thermophysical effects on the surface of functional nanostructured materials obtained with the application of femtosecond laser pulses

    Science.gov (United States)

    Babenko, D. D.; Dmitriev, A. S.; Makarov, P. G.; Mikhailova, I. A.

    2017-11-01

    In recent years, a great scientific and practical interest is caused by functional energy surfaces, modified for certain technological problems. The urgency of the work is to develop promising technologies for thermal and nuclear power engineering, methods for converting solar energy, cooling low-current and high-current electronics devices, energy storage and transport systems on the basis of studying and developing new ways of creating and modifying the functional surfaces of heat exchange and other devices. Modified functional surfaces must have a number of new mechanical and thermophysical properties, including mechanical strength, a new surface morphology for controlling the processes of wetting and spreading working fluids on them, and have high efficiency from the viewpoint of thermohydrodynamic processes of flow and heat and mass transfer of working fluids to them. Among the various ways of modifying surfaces, recently, the method of surface exposure to femtosecond laser pulses (FLI) has become widespread. The technology of femtosecond laser surface treatment (FLPO) of solid materials has shown high efficiency, reliability, high productivity and a huge variety of modification methods. The paper presents new results on the study of thermophysical phenomena - the wetting and spreading of drops of various liquids, the study of the hysteresis of the contact angle, the study of evaporation and boiling processes on functional energy surfaces modified by femtosecond laser pulses. It is shown that in the majority of cases the presence of regular or stochastic nanostructures on the surface leads to a very strong change in the basic properties of the surface, which makes it possible to use such a technology to quickly and efficiently modify and obtain functional energy surfaces for certain predetermined purposes.

  1. Thermophysical properties of HCFC alternatives. Final report, 1 April 1994--31 October 1996

    Energy Technology Data Exchange (ETDEWEB)

    Haynes, W.M.

    1996-11-01

    Numerous fluids and fluid mixtures have been identified as promising alternatives to the HCFC refrigerants, but, for many of them, reliable thermodynamic data do not exist. In particular, reliable thermodynamic properties data and models are needed to predict the performance of the new refrigerants in heating and cooling equipment and to design and optimize equipment to be reliable and energy efficient. The objective of the project is to measure, with high accuracy, selected thermodynamic properties data for one pure refrigerant and nine refrigerant blends; these data will be used to fit equations of state and other property models which can be used in equipment design. The new data will fill in gaps in the existing data and resolve problems and differences that exist in and between existing data sets. Most of the studied fluids and blends are potential replacements for HCFC-22 and/or R-502; in addition, one pure fluid and one blend are potential replacements for CFC-13 in low temperature refrigerant applications.

  2. Thermophysical properties of Gd{sub 2}Zr{sub 2}O{sub 7} powders prepared by mechanical milling: Effect of homovalent Gd{sup 3+} substitution

    Energy Technology Data Exchange (ETDEWEB)

    Díaz-Guillén, J.A., E-mail: jadiaz@itsaltillo.edu.mx [División de Estudios de Posgrado e Investigación, Instituto Tecnológico de Saltillo, 25280 Saltillo, Coahuila (Mexico); Durá, O.J. [GFMA, Departamento de Física Aplicada, Escuela Técnica Superior de Ingenieros Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Díaz-Guillén, M.R. [Instituto de Investigaciones Eléctricas, 62490 Cuernavaca, Morelos (Mexico); Bauer, E. [Institute of Solid State Physics, Vienna University of Technology, Wien A-1040 (Austria); López de la Torre, M.A. [GFMA, Departamento de Física Aplicada, Escuela Técnica Superior de Ingenieros Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Fuentes, A.F. [Cinvestav Unidad Saltillo, Apartado Postal 663, 25000 Saltillo, Coahuila (Mexico)

    2015-11-15

    This contribution analyzes the thermophysical properties of Gd{sub 1.6}Ln{sub 0.4}Zr{sub 2}O{sub 7} (Ln = La{sup 3+}, Nd{sup 3+}, Sm{sup 3+}, Dy{sup 3+} and Er{sup 3+}) ceramics synthesized at room temperature, by mechanically milling stoichiometric mixtures of high purity oxides. Regardless of chemical composition, powders milled for 27 h show XRD patterns similar to fluorite-type materials. Post-milling thermal treatments at 1500 °C, facilitates the evolution to the ordered pyrochlore derivative for Gd{sub 2}Zr{sub 2}O{sub 7}, and the La{sup 3+}-, Nd{sup 3+}-, and Sm{sup 3+}-containing materials. By contrast, samples containing the smaller lanthanides (Dy{sup 3+} or Er{sup 3+}), maintain the fluorite structure. Thermal conductivity of the as-prepared samples was obtained as a function of temperature, from thermal diffusivity, heat capacity and density values, using sintered pellets. We found that doping has an important effect in lowering Gd{sub 2}Zr{sub 2}O{sub 7} thermal conductivity, with final values ranging from 1.22 to 1.94 W m{sup −1} K{sup −1}; Nd{sup 3+}- and Er{sup 3+}-containing samples represent an optimum combination of defects and disordering of oxygen vacancies that generate the lowest conductivity values of all samples tested. - Highlights: • Gd{sub 2}Zr{sub 2}O{sub 7} doped with different lanthanides was synthesized by mechanical milling. • Smaller Ln{sup 3+} yield fluorites whereas larger lanthanides produce pyrochlores. • Thermophysical properties of the samples were measured as a function of temperature. • All samples show low thermal conductivities, and might find application as TBCs. • Doping is a valid strategy to increase Gd{sub 2}Zr{sub 2}O{sub 7} thermal resistance.

  3. Rheological, functional and thermo-physical properties of ultrasound treated whey proteins with addition of sucrose or milk powder

    Directory of Open Access Journals (Sweden)

    Anet Režek Jambrak

    2011-03-01

    Full Text Available Ultrasound represents a non-thermal food processing technique and has great potential to be used in the food industry. The objective of this research was to observe ultrasound impact on physical properties of model systems prepared with whey protein isolates (WPI or whey protein concentrates (WPC with or without sucrose or milk powder addition. This kind of systems is often used in milk beverages and milk based products. Model systems with protein and milk powder or sucrose addition were treated with high power ultrasound (HPU probe of 30 kHz frequency for 5 and 10 minutes. After sonication several properties were determined and examined: solubility, emulsifying and foaming properties, rheological and thermophysical properties. Ultrasound treatment showed severe influence on all examined properties, caused by protein denaturation as a consequence of cavitation and microstreaming effects. Ultrasound treatment caused decrease in protein solubility for whey protein isolate and whey protein concentrates model systems, compared to untreated sample. There was statistically significant increase in foam volume of model systems, prepared with sucrose or milk powder and WPI after ultrasound treatment. Statistically significant decrease in emulsion activity and emulsion stability indices was observed for model systems prepared solely with isolates and concentrates. After treatment of whey protein model systems (with or without milk powder or sucrose with 30 kHz ultrasound, the changes in consistency coefficients (k were observed, but there were no significant changes in flow behaviour indices (n. After addition of milk powder or sucrose, statistically significant decrease in initial freezing and melting temperatures was observed due to the ultrasound treatment.

  4. Thermophysical and rheological properties of dulce de leche with and without coconut flakes as a function of temperature

    Directory of Open Access Journals (Sweden)

    Vanessa Camarinha Barbosa

    2013-03-01

    Full Text Available Dulce de leche (DL, a dairy dessert highly appreciated in Brazil, is a concentrated product containing about 70% m/m of total solids. Thermophysical and rheological properties of two industrial Brazilian Dulce de leche formulations (classic Dulce de leche and Dulce de leche added with coconut flakes 1.5% m/m were determined at temperatures comprised between 28.4 and 76.4 °C. In general, no significant differences (p < 0.05 were observed in the presence of coconut flakes in the two formulations. Heat capacity varied from 2633.2 to 3101.8 J/kg.°C; thermal conductivity from 0.383 to 0.452 W/m.°C; specific mass from 1350.7 to 1310.7 kg/m³; and, thermal diffusivity from (1.082 × 10-7 to 1.130 × 10-7 m²/s. The Bingham model was used to properly describe the non-Newtonian behavior of both formulations, with yielding stress values varying from 27.3 to 17.6 Pa and plastic viscosity from 19.9 to 5.9 Pa.s.

  5. Selected Thermophysical Properties of 2,2 Dimethylcyclopentyl Methylphosphonofluoridate (GP) and 2,2 Dimethylcyclopentanol (DMCP)

    Science.gov (United States)

    2016-09-01

    extrapolation. Vapor pressure correlations were used to infer thermodynamic properties including volatility, enthalpy and entropy of vaporization for GP and...how they disperse when released, and their suitability for explosive dissemination. Physical property information facilitates an understanding of

  6. Robustness and Thermophysical Properties of MOF-5: A Prototypical Hydrogen Storage Material

    Science.gov (United States)

    Ming, Yang

    Metal-organic frameworks (MOFs) are an emerging class of microporous, crystalline materials with potential applications in the capture, storage, and separation of gasses. Of the many known MOFs, the compound known as MOF-5 has attracted considerable attention due to its ability to store gaseous fuels at low pressure with high densities. However, low thermal conductivity and limited robustness upon exposure to water and other reactive species are two challenges which limit the application of MOF-5; similar issues plague several other MOFs. The focus of this dissertation is to understand and overcome these shortcomings through detailed experimental and computational characterization of the prototype compound, MOF-5. The insight provided by this study regarding the properties of MOFs will aid in the transition of these materials from lab bench to applications. Improvements to the thermal conductivity of MOF-5 are demonstrated using densified pellets consisting of a physical mixture of MOF-5 and expanded natural graphite (ENG). The high-aspect ratio of ENG particles, combined with uni-axial compression, results in anisotropic microstructural and thermal transport properties in the pellets. Perpendicular to the pressing direction the thermal conductivity was observed to be two to four times higher than in the orthogonal direction. We further demonstrate that this anisotropy can be exploited to enhance conductivity along a preferred direction in the pellets by altering the pellet processing conditions. We conclude that the low thermal conductivity typical of MOFs can be improved using a judicious combination of second phase additions and processing techniques. Regarding robustness, we first quantify experimentally the impact of humid air exposure on the properties of MOF-5 as a function of exposure time, humidity level, and morphology (i.e., powders vs. pellets). For humidity levels below 50% only minor degradation is observed for exposure times up to several hours. In

  7. The influence of mixing water on the thermophysical properties of nanofluids based on solar salt and silica nanoparticles

    Science.gov (United States)

    Muñoz-Sánchez, B.; Nieto-Maestre, J.; Iparraguirre-Torres, I.; Sánchez-García, J. A.; Julia, J. E.; García-Romero, A.

    2016-05-01

    The use of nanofluids (NFs) based on Solar Salt (SS) and nanoparticles (NPs), either as Thermal Energy Storage (TES) material or as Heat Transfer Fluid (HTF), is attracting great interest in recent years. Many authors [1,3] have reported important improvements on the thermophysical properties (specific heat capacity cp,thermal conductivity k) of NFs based on SS and ceramic NPs. These improvements would lead to important savings and better performance of TES facilities on new Concentrated Solar Power (CSP) plants due to lower quantities of material required and smaller storage tanks. To achieve these advantageous features in the final NFs, it is essential to avoid NP agglomeration during their preparation. Different synthesis procedures have been reported: mixing of solid NPs within a SS solution by means of ultrasounds [1-3], direct mixing of solid NPs and molten salt [4]. In this work, NFs based on SS and 1% by wt. of silica NPs were synthetized from a SS-water solution and a commercial water-silica NF called Ludox HS 30% (Sigma-Aldrich). The influence of the mixing water volume (MW) on the cp of NFs was evaluated. With this aim, the cp of these samples was measured by Differential Scanning Calorimetry (DSC) both in the solid and the liquid state. In addition, the distribution of sizes was measured during the whole preparation process by Dynamic Light Scattering (DLS). Further information about sizes and uniformity of the final NFs was obtained from Scanning Electron Microscopy (SEM) images. X-ray Diffraction (XRD) patterns of the SS and final NF were performed.

  8. The role of hydrogeological conditions and thermophysical properties on the evaluation of geothermal exchange potential in Central Italy

    Science.gov (United States)

    Chicco, Jessica; Verdoya, Massimo; Verda, Vittorio; Invernizzi, Chiara

    2016-04-01

    Within the framework of the EU strategy for sustainable development, the exploitation of the shallow subsurface geothermal resources is of great relevance. In this regard, a multidisciplinary investigation aimed at optimising the performance of borehole heat exchangers is in progress in the Marche region (Central Italy). In particular, an improvement of the present-day knowledge about thermo-physical parameters of the sedimentary deposits forming the Umbria-Marche succession, as well as the hydrogeological setting and geological structures, is fundamental in order to obtain a better picture of the regional geothermal exchange potential. Therefore, we carried out accurate laboratory measurements of thermal conductivity, volume heat capacity, thermal diffusivity, porosity, and density of both core and outcrop samples of the main geological formations of Marche, Moreover, the mineralogical content was defined through XRD diffraction. Because climatic variations can influence the moisture content of the shallower portions of the subsoil, the groundwater physical properties (temperature and electrical conductivity above all), have been continuously monitored for several years. Based on the collected data, a detailed thermo-fluid dynamic modelling was carried out under different, hydrogeological and geo-structural conditions to calculate the effect of groundwater velocity on the heat exchange between the boreholes and the ground. A relation, based on well-known non-dimensional parameters, was obtained in order to correct the purely conductive heat transfer on the basis of groundwater velocity. The preliminary results show that groundwater plays an important role, giving rise to higher heat exchange coefficients. This improves the present-day knowledge of the geothermal exchange potential in the region and overtakes previous analyses that only considered heat conduction.

  9. Influence of hydroxyl group position and temperature on thermophysical properties of tetraalkylammonium hydroxide ionic liquids with alcohols.

    Directory of Open Access Journals (Sweden)

    Pankaj Attri

    Full Text Available In this work, we have explored the thermophysical properties of tetraalkylammonium hydroxide ionic liquids (ILs such as tetrapropylammonium hydroxide (TPAH and tetrabutylammonium hydroxide (TBAH with isomers of butanol (1-butanol, 2-butanol and 2-methyl-2-propanol within the temperature range 293.15-313.15 K, with interval of 5 K and over the varied concentration range of ILs. The molecular interactions between ILs and butanol isomers are essential for understanding the function of ILs in related measures and excess functions are sensitive probe for the molecular interactions. Therefore, we calculated the excess molar volume (V(E and the deviation in isentropic compressibility (Δκs using the experimental values such as densities (ρ and ultrasonic sound velocities (u that are measured over the whole compositions range at five different temperatures (293.15, 298.15, 303.15, 308.15 and 313.15 K and atmospheric pressure. These excess functions were adequately correlated by using the Redlich-Kister polynomial equation. It was observed that for all studied systems, the V(E and Δκs values are negative for the whole composition range at 293.15 K. And, the excess function follows the sequence: 2-butanol>1-butanol>2-methyl-2-propanol, which reveals that (primary or secondary or tertiary position of hydroxyl group influence the magnitude of interactions with ILs. The negative values of excess functions are contributions from the ion-dipole interaction, hydrogen bonding and packing efficiency between the ILs and butanol isomers. Hence, the position of hydroxyl group plays an important role in the interactions with ILs. The hydrogen bonding features between ILs and alcohols were analysed using molecular modelling program by using HyperChem 7.

  10. Influence of hydroxyl group position and temperature on thermophysical properties of tetraalkylammonium hydroxide ionic liquids with alcohols.

    Science.gov (United States)

    Attri, Pankaj; Baik, Ku Youn; Venkatesu, Pannuru; Kim, In Tae; Choi, Eun Ha

    2014-01-01

    In this work, we have explored the thermophysical properties of tetraalkylammonium hydroxide ionic liquids (ILs) such as tetrapropylammonium hydroxide (TPAH) and tetrabutylammonium hydroxide (TBAH) with isomers of butanol (1-butanol, 2-butanol and 2-methyl-2-propanol) within the temperature range 293.15-313.15 K, with interval of 5 K and over the varied concentration range of ILs. The molecular interactions between ILs and butanol isomers are essential for understanding the function of ILs in related measures and excess functions are sensitive probe for the molecular interactions. Therefore, we calculated the excess molar volume (V(E) ) and the deviation in isentropic compressibility (Δκs ) using the experimental values such as densities (ρ) and ultrasonic sound velocities (u) that are measured over the whole compositions range at five different temperatures (293.15, 298.15, 303.15, 308.15 and 313.15 K) and atmospheric pressure. These excess functions were adequately correlated by using the Redlich-Kister polynomial equation. It was observed that for all studied systems, the V(E) and Δκs values are negative for the whole composition range at 293.15 K. And, the excess function follows the sequence: 2-butanol>1-butanol>2-methyl-2-propanol, which reveals that (primary or secondary or tertiary) position of hydroxyl group influence the magnitude of interactions with ILs. The negative values of excess functions are contributions from the ion-dipole interaction, hydrogen bonding and packing efficiency between the ILs and butanol isomers. Hence, the position of hydroxyl group plays an important role in the interactions with ILs. The hydrogen bonding features between ILs and alcohols were analysed using molecular modelling program by using HyperChem 7.

  11. Vapor pressures and thermophysical properties of selected hexenols and recommended vapor pressure for hexan-1-ol

    Czech Academy of Sciences Publication Activity Database

    Štejfa, V.; Fulem, Michal; Růžička, K.; Matějka, P.

    2015-01-01

    Roč. 402, Sep (2015), 18-29 ISSN 0378-3812 Institutional support: RVO:68378271 Keywords : alcohols * vapor pressure * heat capacity * ideal - gas thermodynamic properties * vaporization enthalpy Subject RIV: BJ - Thermodynamics Impact factor: 1.846, year: 2015

  12. Thermophysical parameters of coconut oil and its potential application as the thermal energy storage system in Indonesia

    Science.gov (United States)

    Putri, Widya A.; Fahmi, Zulfikar; Sutjahja, I. M.; Kurnia, D.; Wonorahardjo, S.

    2016-08-01

    The high consumption of electric energy for room air conditioning (AC) system in Indonesia has driven the research of potential thermal energy storage system as a passive temperature controller. The application of coconut oil (CO) as the potential candidate for this purpose has been motivated since its working temperature just around the human thermal comfort zone in the tropical area as Indonesia. In this research we report the time-dependent temperature data of CO, which is adopting the T-history method. The analysis of the data revealed a set of thermophysical parameters, consist of the mean specific heats of the solid and liquid, as well as the latent heat of fusion for the phase change transition. The performance of CO to decrease the air temperature was measured in the thermal chamber. From the results it is shown that the latent phase of CO related to the solid-liquid phase transition show the highest capability in heat absorption, directly showing the potential application of CO as thermal energy storage system in Indonesia.

  13. MYRRHA ADS DATABASE: Part I. Thermophysical properties of molten lead-bismuth eutectic. Version 1

    International Nuclear Information System (INIS)

    Sobolev, V.

    2005-11-01

    This report is an update of the internal SCK-CEN report IR-18 'Database of thermal properties for the melted lead-bismuth eutectic' issued in 2002. This compilation takes into account larger amount of original sources and, partially, the work performed in the framework of the preparation of a 'zero' version of the HLMC Handbook by the OECD/NEA Working Group on LBE Technology. An analysis is performed of the previous recommendations using some general physical laws and referencing to the properties of lead and bismuth. The updated and extended version of the molten LBE thermal properties database is developed and the correlations are proposed for the design calculations of ADS MYRRHA. (author)

  14. Effects of spatial gradients in thermophysical properties on the topology of turbulence in heated channel flow of supercritical fluids

    Science.gov (United States)

    Azih, Chukwudi; Yaras, Metin I.

    2018-01-01

    The current literature suggests that large spatial gradients of thermophysical properties, which occur in the vicinity of the pseudo-critical thermodynamic state, may result in significant variations in forced-convection heat transfer rates. Specifically, these property gradients induce inertia- and buoyancy-driven phenomena that may enhance or deteriorate the turbulence-dominated heat convection process. Through direct numerical simulations, the present study investigates the role of coherent flow structures in channel geometries for non-buoyant and buoyant flows of supercritical water, with buoyant configurations involving wall-normal oriented gravitational acceleration and downstream-oriented gravitational acceleration. This sequence of simulations enables the evaluation of the relative contributions of inertial and buoyancy phenomena to heat transfer variations. In these simulations, the state of the working fluid is in the vicinity of the pseudo-critical point. The uniform wall heat flux and the channel mass flux are specified such that the heat to mass flux ratio is 3 kJ/kg, with an inflow Reynolds number of 12 000 based on the channel hydraulic diameter, the area-averaged inflow velocity, and fluid properties evaluated at the bulk temperature and pressure of the inflow plane. In the absence of buoyancy forces, notable reductions in the density and viscosity in close proximity of the heated wall are observed to promote generation of small-scale vortices, with resultant breakdown into smaller scales as they interact with preexisting larger near-wall vortices. This interaction results in a reduction in the overall thermal mixing at particular wall-normal regions of the channel. Under the influence of wall-normal gravitational acceleration, the wall-normal density gradients are noted to enhance ejection motions due to baroclinic vorticity generation on the lower wall, thus providing additional wall-normal thermal mixing. Along the upper wall, the same mechanism

  15. Thermophysical properties of starch and whey protein composite prepared in presence of organic acid and esters

    Science.gov (United States)

    Previously, we prepared starch and protein composite by reactive mixing in presence of various organic acids and found that use of these acid esters resulted in composites with good mechanical properties. In this study, concentration (% w/w) of acid citrates in the starch-protein composites were var...

  16. Effect of gamma irradiation on thermophysical properties of plasticized starch and starch surfactant films

    Science.gov (United States)

    Cieśla, Krystyna; Watzeels, Nick; Rahier, Hubert

    2014-06-01

    In this work the influence of gamma irradiation on the thermomechanical properties of the films formed in potato starch-glycerol and potato starch-glycerol-surfactant systems were examined by Dynamic Mechanical Analysis, DMA, and Differential Scanning Calorimetry, DSC, and the results were correlated to the amount of the volatile fraction in the films.

  17. International Nuclear Safety Center database on thermophysical properties of reactor materials

    International Nuclear Information System (INIS)

    Fink, J.K.; Sofu, T.; Ley, H.

    1997-01-01

    The International Nuclear Safety Center (INSC) database has been established at Argonne National Laboratory to provide easily accessible data and information necessary to perform nuclear safety analyses and to promote international collaboration through the exchange of nuclear safety information. The INSC database, located on the World Wide Web at http://www.insc.anl.gov, contains critically assessed recommendations for reactor material properties for normal operating conditions, transients, and severe accidents. The initial focus of the database is on thermodynamic and transport properties of materials for water reactors. Materials that are being included in the database are fuel, absorbers, cladding, structural materials, coolant, and liquid mixtures of combinations of UO 2 , ZrO 2 , Zr, stainless steel, absorber materials, and concrete. For each property, the database includes: (1) a summary of recommended equations with uncertainties; (2) a detailed data assessment giving the basis for the recommendations, comparisons with experimental data and previous recommendations, and uncertainties; (3) graphs showing recommendations, uncertainties, and comparisons with data and other equations; and (4) property values tabulated as a function of temperature

  18. Investigation of Structure and Dynamics in Disordered Materials Using Containerless Techniques with In-Situ Quantum Beam and Thermophysical Property Measurements

    Directory of Open Access Journals (Sweden)

    Shinji Kohara

    2018-02-01

    Full Text Available The use of levitation (containerless techniques can enable new scientific discoveries because deeply undercooled and metastable liquids can be achieved over a wide temperature range. This review article summarizes the state-of-art instrumentation for structure measurements at synchrotron radiation/neutron sources and for thermophysical property measurements not only on the ground but also in microgravity utilizing the International Space Station (ISS. Furthermore, we introduce recent scientific topics on high-temperature oxide liquids and oxide glasses synthesized from levitated undercooled liquids by the use of quantum beam measurements analyzed using advanced computation.

  19. Database of thermophysical properties of liquid metal coolants for GEN-IV

    International Nuclear Information System (INIS)

    Sobolev, V.

    2011-01-01

    The report presents an Fe-Cr interatomic potential to model high-Cr ferritic alloys. The potential is fitted to thermodynamic and point-defect properties obtained from density functional theory (DFT) calculations and experiments. The developed potential is also benchmarked against other potentials available in literature. It shows particularly good agreement with the DFT obtained mixing enthalpy of the random alloy, the formation energy of intermetallics and experimental excess vibrational entropy and phase diagram. In addition, DFT calculated point-defect properties, both interstitial and substitutional, are well reproduced, as is the screw dislocation core structure. As a first validation of the potential, we study the precipitation hardening of Fe-Cr alloys via static simulations of the interaction between Cr precipitates and screw dislocations. It is concluded that the description of the dislocation core modification near a precipitate might have a significant influence on the interaction mechanisms observed in dynamic simulations.

  20. Experimental study of thermophysical properties of thin-film coatings based on hollow microspheres

    Science.gov (United States)

    Bukhmirov, V. V.; Gaskov, A. K.

    2017-11-01

    The paper describes results of an experimental study of thermal properties of energy-efficient thin-film coatings based on hollow glass microspheres MS-V2L in a styrene acrylic dispersion binder «Akrilan 101». A value of energy-efficient paint thermal conductivity depending on its composition and temperature and a value of the thermal diffusivity of the paint were experimentally determined. Data on the energy saving paint density and specific heat capacity were also obtained.

  1. Thermophysical Properties of Sn-Ag-Cu Based Pb-Free Solders

    Science.gov (United States)

    Kim, Sok Won; Lee, Jaeran; Jeon, Bo-Min; Jung, Eun; Lee, Sang Hyun; Kang, Kweon Ho; Lim, Kwon Taek

    2009-06-01

    Lead-tin (Pb-Sn) alloys are the dominant solders used for electronic packaging because of their low cost and superior properties required for interconnecting electronic components. However, increasing environmental and health concerns over the toxicity of lead, combined with global legislation to limit the use of Pb in manufactured products, have led to extensive research and development studies of lead-free solders. The Sn-Ag-Cu ternary eutectic alloy is considered to be one of the promising alternatives. Except for thermal properties, much research on several properties of Sn-Ag-Cu alloy has been performed. In this study, five Sn-xAg-0.5Cu alloys with variations of Ag content x of 1.0 mass%, 2.5 mass%, 3.0 mass%, 3.5 mass%, and 4.0 mass% were prepared, and their thermal diffusivity and specific heat were measured from room temperature to 150 °C, and the thermal conductivity was calculated using the measured thermal diffusivity, specific heat, and density values. Also, the linear thermal expansion was measured from room temperature to 170 °C. The results show that Sn-3.5Ag-0.5Cu is the best candidate because it has a maximum thermal conductivity and a low thermal expansion, which are the ideal conditions to be a proper packaging alloy for effective cooling and thermostability.

  2. Thermophysical Properties of Matter - the TPRC Data Series. Volume 12. Thermal Expansion Metallic Elements and Alloys

    Science.gov (United States)

    1975-01-01

    Cobalt, and the Cause of the Small Expansibility of Alloys of the Invar Type," Sci. Reports Tohoku Univ., 20, 101-23, 1931. 60 37540 Holborn, L. and Day...H., "On the Thermal Expansion of Alloys of Cobalt, Iron, and Chromium, a! a New Alloy Stainless- Invar ," Si. Rept. Tohoku Imp. Univ., 23, 265-80, 1934...USSR), 23(4), 201-3, 1967. 528 46149 Kachi, S. and Asano, H., "Concentration Fluctuations and Anomalous Properties of the Invar Alloy ," J. Phys. Soc

  3. Thermophysical and Mechanical Properties of Hardened Cement Paste with Microencapsulated Phase Change Materials for Energy Storage.

    Science.gov (United States)

    Cui, Hongzhi; Liao, Wenyu; Memon, Shazim Ali; Dong, Biqin; Tang, Waiching

    2014-12-16

    In this research, structural-functional integrated cement-based materials were prepared by employing cement paste and a microencapsulated phase change material (MPCM) manufactured using urea-formaldehyde resin as the shell and paraffin as the core material. The encapsulation ratio of the MPCM could reach up to 91.21 wt%. Thermal energy storage cement pastes (TESCPs) incorporated with different MPCM contents (5%, 10%, 15%, 20% and 25% by weight of cement) were developed, and their thermal and mechanical properties were studied. The results showed that the total energy storage capacity of the hardened cement specimens with MPCM increased by up to 3.9-times compared with that of the control cement paste. The thermal conductivity at different temperature levels (35-36 °C, 55-56 °C and 72-74 °C) decreased with the increase of MPCM content, and the decrease was the highest when the temperature level was 55-56 °C. Moreover, the compressive strength, flexural strength and density of hardened cement paste decreased with the increase in MPCM content linearly. Among the evaluated properties, the compressive strength of TESCPs had a larger and faster degradation with the increase of MPCM content.

  4. Thermophysical and Mechanical Properties of Hardened Cement Paste with Microencapsulated Phase Change Materials for Energy Storage

    Directory of Open Access Journals (Sweden)

    Hongzhi Cui

    2014-12-01

    Full Text Available In this research, structural-functional integrated cement-based materials were prepared by employing cement paste and a microencapsulated phase change material (MPCM manufactured using urea-formaldehyde resin as the shell and paraffin as the core material. The encapsulation ratio of the MPCM could reach up to 91.21 wt%. Thermal energy storage cement pastes (TESCPs incorporated with different MPCM contents (5%, 10%, 15%, 20% and 25% by weight of cement were developed, and their thermal and mechanical properties were studied. The results showed that the total energy storage capacity of the hardened cement specimens with MPCM increased by up to 3.9-times compared with that of the control cement paste. The thermal conductivity at different temperature levels (35–36 °C, 55–56 °C and 72–74 °C decreased with the increase of MPCM content, and the decrease was the highest when the temperature level was 55–56 °C. Moreover, the compressive strength, flexural strength and density of hardened cement paste decreased with the increase in MPCM content linearly. Among the evaluated properties, the compressive strength of TESCPs had a larger and faster degradation with the increase of MPCM content.

  5. Intermediate Co/Ni-base model superalloys — Thermophysical properties, creep and oxidation

    International Nuclear Information System (INIS)

    Zenk, Christopher H.; Neumeier, Steffen; Engl, Nicole M.; Fries, Suzana G.; Dolotko, Oleksandr; Weiser, Martin; Virtanen, Sannakaisa; Göken, Mathias

    2016-01-01

    The mechanical properties of γ′-strengthened Co–Ni–Al–W–Cr model superalloys extending from pure Ni-base to pure Co-base superalloys have been assessed. Differential scanning calorimetry measurements and thermodynamic calculations match well and show that the γ′ solvus temperature decreases with increasing Co-content. The γ/γ′ lattice misfit is negative on the Ni- and positive on the Co-rich side. High Ni-contents decelerate the oxidation kinetics up to a factor of 15. The creep strength of the Ni-base alloy increases by an order of magnitude with additions of Co before it deteriorates strongly upon higher additions despite an increasing γ′ volume fraction.

  6. Influence of fly ash added to a ceramic body on its thermophysical properties

    Directory of Open Access Journals (Sweden)

    Kováč Jozef

    2016-01-01

    Full Text Available We study thermal expansion, mass changes, heat capacity, and thermal diffusivity and conductivity for a ceramic body with 20 mass% and without fly ash content, using the TDA, TG, DTA, DSC, and flash method. The measurements were performed (a for green samples either isothermally or by a linear heating up to a temperature 600°C, 1050°C, or 1100°C, depending on the measurement method; (b at the room temperature for samples preheated at 100°C, 200°C, ..., 1100°C. In case (a addition of fly ash changes the final contraction only above ~900°C, while the thermal properties remain almost unchanged. In case (b the final contraction of samples at 1100°C is the same. The thermal diffusivity is nearly identical up to 700°C, and fly ash causes the diffusivity to stay almost constant up to 1000°C.

  7. Thermophysical properties of N, N-dimethylacetamide mixtures with n-butanol

    Science.gov (United States)

    Maharolkar, Aruna P.; Murugkar, A. G.; Khirade, P. W.; Mehrotra, S. C.

    2017-09-01

    The refraction, dielectric, viscosity, density, data of the binary mixtures of N, N-dimethylacetamide (DMA) with n-butanol at 308.15 and 313.15 K. The measured parameters used to obtain derived properties like Bruggeman factor, molar refraction and excess static dielectric constant, excess inverse relaxation time, excess molar volume and excess viscosity, excess molar refraction. The variation in magnitude with composition and temperature of these quantities has been used to discuss the type, strength and nature of binary interactions. Results confirm that there are strong hydrogen-bond interactions between unlike molecules of DMA+ n-butanol mixtures and that 1: 1 complexes are formed and strength of intermolecular interaction increases with temperature.

  8. High temperature thermo-physical properties of SPS-ed W–Cu functional gradient materials

    Science.gov (United States)

    Galatanu, Magdalena; Enculescu, Monica; Galatanu, Andrei

    2018-02-01

    The divertor of a fusion reactor like DEMO requires materials able to withstand high heat fluxes and neutron irradiation for several years. For the water cooling concept of this essential part of the reactor, the most likely plasma facing material will be W, while the heatsink material considered is CuCrZr or an improved version of such a Cu-based alloy. To realize W–Cu alloy joints able to withstand thousands of thermal cycles can be difficult due to the difference between the thermal expansion coefficients of these materials. In this work we investigate the possibility to realize such joints by using W–Cu functional gradient materials (FGMs) produced from nanometric and micrometric metallic powders mixtures and consolidated by spark plasma sintering at about 900 °C. Morphological and thermal properties investigations, performed for typical compositions, shows that the best results are obtained using powders with micrometric dimensions. A resulting 1 mm thick, 3 layers W–Cu FGM produced by this simple method shows a remarkable almost constant thermal conductivity value of 200 W m‑1 K‑1, from room temperature up to 1000 °C.

  9. Investigation on some thermophysical properties of poly(ethylene glycol) binary mixtures at different temperatures

    International Nuclear Information System (INIS)

    Moosavi, Mehrdad; Motahari, Ahmad; Omrani, Abdollah; Rostami, Abbas Ali

    2013-01-01

    Highlights: ► Measuring densities and viscosities for binary mixtures of PEG + water or alcohols. ► Finding excess molar volume, refractive index and coefficient of thermal expansion. ► Estimating binary coefficients using Redlich–Kister polynomial equation. ► Deducing excess Gibbs free energy of activation and other activation parameters. ► Correlation of viscosity data with Grunberg–Nissan and Tamura–Kurata equations. -- Abstract: Densities ρ and viscosities η for the binary mixtures of poly(ethylene glycol) + water, + 1,2-ethanediol, + 1,3-propanediol, + 1,4-butanediol over the entire concentration range were determined at temperatures (298.15 to 308.15) K with 5 K interval. The experimental data were used to calculate the excess molar volume V m E , coefficient of thermal expansion α, excess coefficient of thermal expansion α E , excess Gibbs free energy of activation ΔG ∗E , and other activation parameters (i.e., ΔG ∗ ,ΔH ∗ ,ΔS ∗ ). The values of excess properties were fitted to Redlich–Kister polynomial equation to estimate the binary coefficients. The excess refractive index n E and electronic polarizability α e of PEG + water binary mixtures were also determined from the experimental values of refractive indices. The viscosity data were correlated with Grunberg–Nissan and Tamura–Kurata equations. Moreover, the Prigogine–Flory–Patterson theory has been used to correlate the excess molar volumes of the studied mixtures

  10. Effect of gamma irradiation on thermophysical properties of plasticized starch and starch surfactant films

    International Nuclear Information System (INIS)

    Cieśla, Krystyna; Watzeels, Nick; Rahier, Hubert

    2014-01-01

    In this work the influence of gamma irradiation on the thermomechanical properties of the films formed in potato starch–glycerol and potato starch–glycerol–surfactant systems were examined by Dynamic Mechanical Analysis, DMA, and Differential Scanning Calorimetry, DSC, and the results were correlated to the amount of the volatile fraction in the films. The starch was irradiated with a dose of 30 kGy. The films were prepared by casting from solutions with addition of 0, 20 and 30 wt% of glycerol. Two endotherms attributed to glass transitions were observed in water or glycerol plasticised samples, the first one shifting to higher temperature after irradiation. A similar shift was observed after irradiation of films prepared from starch–sodium laurate and starch–sodium palmitate systems, while a decrease in glass transition temperature was observed in the case of starch–cetyltrimethylammonium bromide films. Small differences in the content of the volatile fraction reached after the appropriate conditioning had no impact on the direction of temperature shift of Tg observed after irradiation. - Highlights: • The films were prepared basing starch, surfactant and glycerol. • Two glass transitions were observed showing an existence of two phase system. • The first Tg of the starch–CTAB films shifts after irradiation to lower temperature. • In all the other cases it shifts after irradiation to higher temperature. • Differences in volatile fractions content are not important for the temperature shift

  11. On-line determination of thermophysical properties in an absorption calorimeter

    Science.gov (United States)

    Otieno, F. O.; Kola, B. O.; Onyango, F. N.

    1997-03-01

    A Microsoft FORTRAN 77 algorithm for calculation of the thermal absorptance 0957-0233/8/3/004/img1 and emittance 0957-0233/8/3/004/img2 of materials for solar photothermal applications is presented. It replaces the Mathematica software package used for an earlier paper and uses data from sample heating and cooling histories obtained in an absorption calorimeter. The calorimeter is automated with a Z80 microprocessor system, which has an operating system (OS) and control programs resident in a block of type 2716 EPROMs with a working memory comprising Hitachi type 6116 static RAMs. The 0957-0233/8/3/004/img3 system acquires data from the sample through thermocouples, filters, amplifiers and analogue-to-digital signal converters (ADCs) for temporary storage in the on-board RAM. The raw data are uploaded to an IBM PS/2 microcomputer for display and processing. Solutions of heat balance equations of the calorimeter are computed from the transient temperature history data using analytical and numerical methods. Results obtained for commercial copper and aluminium samples using a 60 W tungsten - halogen lamp are discussed. They compare well with those from the Mathematica package.

  12. Face-Sheet Quality Analysis and Thermo-Physical Property Characterization of OOA and Autoclave Panels

    Science.gov (United States)

    Miller, Sandi G.; Lort, Richard D., III; Zimmerman, Thomas J.; Sutter, James K.; Pelham, Larry I.; McCorkle, Linda S.; Scheiman, Daniel A.

    2012-01-01

    Increased application of polymer matrix composite (PMC) materials in large vehicle structures requires consideration of non-autoclave manufacturing technology. The NASA Composites for Exploration project, and its predecessor, Lightweight Spacecraft Structures and Materials project, were tasked with the development of materials and manufacturing processes for structures that will perform in a heavy-lift-launch vehicle environment. Both autoclave and out of autoclave processable materials were considered. Large PMC structures envisioned for such a vehicle included the payload shroud and the interstage connector. In this study, composite sandwich panels representing 1/16th segments of the barrel section of the Ares V rocket fairing were prepared as 1.8 m x 2.4 m sections of the 10 m diameter arc segment. IM7/977-3 was used as the face-sheet prepreg of the autoclave processed panels and T40-800B/5320-1 for the out of autoclave panels. The core was 49.7 kg/sq m (3.1 lb/cu ft (pcf)) aluminum honeycomb. Face-sheets were fabricated by automated tape laying 153 mm wide unidirectional tape. This work details analysis of the manufactured panels where face-sheet quality was characterized by optical microscopy, cured ply thickness measurements, acid digestion, and thermal analysis.

  13. Cold spraying SiC/Al metal matrix composites: effects of SiC contents and heat treatment on microstructure, thermophysical and flexural properties

    Science.gov (United States)

    Gyansah, L.; Tariq, N. H.; Tang, J. R.; Qiu, X.; Feng, B.; Huang, J.; Du, H.; Wang, J. Q.; Xiong, T. Y.

    2018-02-01

    In this paper, cold spray was used as an additive manufacturing method to fabricate 5 mm thick SiC/Al metal matrix composites with various SiC contents. The effects of SiC contents and heat treatment on the microstructure, thermophysical and flexural properties were investigated. Additionally, the composites were characterized for retention of SiC particulates, splat size, surface roughness and the progressive understanding of strengthening, toughening and cracking mechanisms. Mechanical properties were investigated via three-point bending test, thermophysical analysis, and hardness test. In the as-sprayed state, flexural strength increased from 95.3 MPa to 133.5 MPa, an appreciation of 40% as the SiC contents increased, and the main toughening and strengthening mechanisms were zigzag crack propagation and high retention of SiC particulates respectively. In the heat treatment conditions, flexural strength appreciated significantly compared to the as-sprayed condition and this was as a result of coarsening of pure Al splat. Crack branching, crack deflection and interface delamination were considered as the main toughening mechanisms at the heat treatment conditions. Experimental results were consistent with the measured CTE, hardness, porosity and flexural modulus.

  14. Modification of wheat starch with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures I. Thermophysical and pasting properties.

    Science.gov (United States)

    Subarić, Drago; Ačkar, Durđica; Babić, Jurislav; Sakač, Nikola; Jozinović, Antun

    2014-10-01

    The aim of this research was to investigate the influence of modification with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures on thermophysical and pasting properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetic anhydride, and azelaic acid and acetic anhydride in 4, 6 and 8 % (w/w). Thermophysical, pasting properties, swelling power, solubility and amylose content of modified starches were determined. The results showed that modifications with mixtures of afore mentioned dicarboxylic acids with acetic anhydride decreased gelatinisation and pasting temperatures. Gelatinisation enthalpy of Golubica starch increased, while of Srpanjka starch decreased by modifications. Retrogradation after 7 and 14 day-storage at 4 °C decreased after modifications of both starches. Maximum, hot and cold paste viscosity of both starches increased, while stability during shearing at high temperatures decreased. % setback of starches modified with azelaic acid/acetic anhydride mixture decreased. Swelling power and solubility of both starches increased by both modifications.

  15. Thermo-Physical Properties of B2O3-Containing Mold Flux for High Carbon Steels in Thin Slab Continuous Casters: Structure, Viscosity, Crystallization, and Wettability

    Science.gov (United States)

    Park, Jun-Yong; Kim, Gi Hyun; Kim, Jong Bae; Park, Sewoong; Sohn, Il

    2016-08-01

    The effect of B2O3 on the thermo-physical properties of commercial mold fluxes, including the viscosity, crystallization behavior, and wettability, was investigated. Viscosity was measured using the rotating spindle method, and CCT (continuous cooling transformation) diagrams were obtained to investigate the crystallization behavior at various cooling rates using CLSM (confocal laser scanning microscope). The wettability of the fluxes was determined by measuring the contact angles at 1573 K (1300 °C) using the digital images generated by the sessile drop method and were used to calculate the surface tension, interfacial tension, and work of adhesion for Flux A (existing flux) and B (modified flux). These thermo-physical properties were correlated with the structural analysis obtained using FT-IR (Fourier transform-infrared), Raman and MAS-NMR (magic angle spin-nuclear magnetic resonance) spectroscopy. In addition, DTA (differential thermal analysis) was performed on the samples to measure the liquidus temperatures. Higher B2O3 concentrations resulted in lower liquidus temperatures, consequently decreasing the viscosity, the break temperature, and the crystallization temperature. However, B2O3 addition accelerated crystal growth owing to the higher diffusion kinetics of the cations, which also reduced the size of the liquid/solid co-existing region.

  16. New lubrication concepts for environmental friendly machines. Tribological, thermophysical and viscometric properties of lubricants interacting with triboactive materials

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, R.; Klingenberg, G. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Woydt, M. [Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin (Germany)

    2006-07-01

    The present research report was elaborated in close cooperation with Renault SAS, FUCHS Petrolub AG and Ingenieurgesellschaft Auto und Verkehr (IAV). The use of alternative oils for the lubrication of automobile engines has a potential of ecological and technical advantages. It requires the detailed knowledge of several thermophysical and viscometric properties in a large temperature range (mapping). Therefore, the following properties of up to twenty-eight different oils have been measured in the temperature range from 22 C to 150 C: density, heat capacity, thermal conductivity, viscosity at ambient pressure, viscosity under shear rates above 10{sup 6} s{sup -1}, and the viscosity at elevated pressures (maximum 100 MPa). The last two have been measured with a substantially improved and a newly developed apparatus, respectively. The pressure-viscosity coefficient has been measured on four hydrocarbon-based, factory-fill oils, a paraffin oil and twenty-three alternative oils. Nine of the alternative oils are based partly or completely on esters, the other fourteen on polyglycols, two of them additionally on water. Based on the piston ring/cylinder liner simulation tests of BAM performed outside of engines and the SRV {sup registered} tests both performed only under conditions of mixed/boundary lubrication, it is reasonable that thermally sprayed TiO{sub x}-based, Ti{sub n-2}Cr{sub 2}O{sub 2n-1} and (Ti,Mo)(C,N)+23NiMo piston ring coatings, so called 'lubricious or triboactive oxides', can substitute common materials and serve as a promising alternative to commercial piston ring coatings made of strategic Molybdenum and super-finishing intensive blends of WC/Cr{sub 3}C{sub 2}. Some couples qualified for 'zero' wear. In combination with bionotox ester- and polyglycol-based lubricants the coefficient of friction can be reduced fulfilling simultaneously stronger European exhaust emission regulations. Thermally sprayed Ti-based coatings with their

  17. Thermophysical Properties of Matter - The TPRC Data Series. Volume 7. Thermal Radiative Properties - Metallic Elements and Alloys

    Science.gov (United States)

    1970-01-01

    an evaluative review of the data. This analysis work is first a filtering process; it identifies data which are felt to be reliably or typically...ether volumes of this Series; the work is intended to make the best reliable data available to the thermal designer. As stated earlier, all data...only limited application. Goniometrie reflectance methods, which measure the geometric distribution of the reflected radiant energy are described

  18. Experimental and molecular dynamics study of thermo-physical and transport properties of ThO{sub 2}-5wt.%CeO{sub 2} mixed oxides

    Energy Technology Data Exchange (ETDEWEB)

    Somayajulu, P.S. [Radiometallurgy Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Ghosh, P.S., E-mail: psghosh@barc.gov.in [Material Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Banerjee, J. [Radiometallurgy Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Babu, K.L.N.C. [Metallic Fuels Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Danny, K.M. [Radiometallurgy Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Mandal, B.P. [Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Mahata, T. [Powder Metallurgy Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Sengupta, P. [Material Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Sali, S.K. [Fuel Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Arya, A. [Material Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2015-12-15

    We have determined the thermo-physical (elastic modulus, specific heat, thermal expansion and thermal conductivity) and transport (ionic conductivity) properties of ThO{sub 2}-5wt.%CeO{sub 2} mixed oxide (MOX) using a combined experimental and theoretical methodology. The specific heat, ionic conductivity and elastic properties of ThO{sub 2}-5wt.%CeO{sub 2} pellets prepared by conventional powder metallurgy (POP) and coated agglomerate pelletization (CAP) routes (sintered in both air and Ar-8%H{sub 2} atmosphere) are compared with respect to homogeneity (CeO{sub 2} distribution in ThO{sub 2} matrix), microstructure, porosity and oxygen to metal ratio. The effects of inhomogeneity and pore distribution on thermal expansion and thermal conductivity of the mixed-oxide pellets are identified. Molecular dynamics (MD) simulations using the Coulomb-Buckingham-Morse-many-body model based interatomic potentials are used to predict elastic properties in the temperature range between 300 and 2000 K and thermodynamic properties, viz., enthalpy increment and specific heats of ThO{sub 2}. Finally, the thermal expansion coefficient and thermal conductivity of ThO{sub 2} and (Th,Ce)O{sub 2} mixed-oxides obtained from MD are compared with available experimental results.

  19. Experimental and molecular dynamics study of thermo-physical and transport properties of ThO2-5wt.%CeO2 mixed oxides

    Science.gov (United States)

    Somayajulu, P. S.; Ghosh, P. S.; Banerjee, J.; Babu, K. L. N. C.; Danny, K. M.; Mandal, B. P.; Mahata, T.; Sengupta, P.; Sali, S. K.; Arya, A.

    2015-12-01

    We have determined the thermo-physical (elastic modulus, specific heat, thermal expansion and thermal conductivity) and transport (ionic conductivity) properties of ThO2-5wt.%CeO2 mixed oxide (MOX) using a combined experimental and theoretical methodology. The specific heat, ionic conductivity and elastic properties of ThO2-5wt.%CeO2 pellets prepared by conventional powder metallurgy (POP) and coated agglomerate pelletization (CAP) routes (sintered in both air and Ar-8%H2 atmosphere) are compared with respect to homogeneity (CeO2 distribution in ThO2 matrix), microstructure, porosity and oxygen to metal ratio. The effects of inhomogeneity and pore distribution on thermal expansion and thermal conductivity of the mixed-oxide pellets are identified. Molecular dynamics (MD) simulations using the Coulomb-Buckingham-Morse-many-body model based interatomic potentials are used to predict elastic properties in the temperature range between 300 and 2000 K and thermodynamic properties, viz., enthalpy increment and specific heats of ThO2. Finally, the thermal expansion coefficient and thermal conductivity of ThO2 and (Th,Ce)O2 mixed-oxides obtained from MD are compared with available experimental results.

  20. Elastic and thermo-physical properties of TiC, TiN, and their intermediate composition alloys using ab initio calculations

    International Nuclear Information System (INIS)

    Kim, Jiwoong; Kang, Shinhoo

    2012-01-01

    Highlights: ► Elastic properties of TiC, TiN and their alloys were calculated by ab initio calculations. ► Debye temperature and Gruneisen constant of TiC, TiN and their alloys were calculated as a function of nitrogen content. ► Thermo-physical properties were calculated as a function of nitrogen content. ► Thermal expansion of the alloys was fitted in different temperature range. - Abstract: The equilibrium lattice parameters, elastic properties, material brittleness, heat capacities, and thermal expansion coefficients of TiC, TiN, and their intermediate composition alloys (Ti(C 1−x N x ), x = 0.25, 0.5, and 0.75) were calculated using ab initio density functional theory (DFT) methods. We employed the Debye–Gruneisen model to calculate a finite temperature heat capacity and thermal expansion coefficient. The calculated elastic moduli and thermal expansion coefficients agreed well with the experimental data and with other DFT calculations. Accurate heat capacities of TiC, TiN, and their intermediate composition alloys were obtained by calculating not only the phonon contributions but also the electron contributions to the heat capacity. Our calculations indicated that the heat capacity differences between each composition originated mainly from the electronic contributions.

  1. The Effects of Thermophysical Properties and Environmental Conditions on Fire Performance of Intumescent Coatings on Glass Fibre-Reinforced Epoxy Composites

    Directory of Open Access Journals (Sweden)

    Baljinder K. Kandola

    2015-08-01

    Full Text Available Intumescent coatings are commonly used as passive fire protection systems for steel structures. The purpose of this work is to explore whether these can also be used effectively on glass fibre-reinforced epoxy (GRE composites, considering the flammability of the composites compared to non-flammable steel substrate. The thermal barrier and reaction-to-fire properties of three commercial intumescent coatings on GRE composites have been studied using a cone calorimeter. Their thermophysical properties in terms of heating rate and/or temperature dependent char expansion ratios and thermal conductivities have been measured and correlated. It has been suggested that these two parameters can be used to design coatings to protect composite laminates of defined thicknesses for specified periods of time. The durability of the coatings to water absorption, peeling, impact, and flexural loading were also studied. A strong adhesion between all types of coatings and the substrate was observed. Water soaking had a little effect on the fire performance of epoxy based coatings. All types of 1 mm thick coatings on GRE helped in retaining ~90% of the flexural property after 2 min exposure to 50 kW/m2 heat flux whereas the uncoated laminate underwent severe delamination and loss in structural integrity after 1 min.

  2. The Effects of Thermophysical Properties and Environmental Conditions on Fire Performance of Intumescent Coatings on Glass Fibre-Reinforced Epoxy Composites.

    Science.gov (United States)

    Kandola, Baljinder K; Luangtriratana, Piyanuch; Duquesne, Sophie; Bourbigot, Serge

    2015-08-11

    Intumescent coatings are commonly used as passive fire protection systems for steel structures. The purpose of this work is to explore whether these can also be used effectively on glass fibre-reinforced epoxy (GRE) composites, considering the flammability of the composites compared to non-flammable steel substrate. The thermal barrier and reaction-to-fire properties of three commercial intumescent coatings on GRE composites have been studied using a cone calorimeter. Their thermophysical properties in terms of heating rate and/or temperature dependent char expansion ratios and thermal conductivities have been measured and correlated. It has been suggested that these two parameters can be used to design coatings to protect composite laminates of defined thicknesses for specified periods of time. The durability of the coatings to water absorption, peeling, impact, and flexural loading were also studied. A strong adhesion between all types of coatings and the substrate was observed. Water soaking had a little effect on the fire performance of epoxy based coatings. All types of 1 mm thick coatings on GRE helped in retaining ~90% of the flexural property after 2 min exposure to 50 kW/m² heat flux whereas the uncoated laminate underwent severe delamination and loss in structural integrity after 1 min.

  3. Effect of high doses of gamma radiation on thermophysical properties of ZrO{sub 2} nanofluids in aqueous base

    Energy Technology Data Exchange (ETDEWEB)

    Pinho, Priscila G.M.; Rocha, Marcelo S., E-mail: pri.pgm@gmail.com, E-mail: msrocha@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    This work conducts a general theoretical and experimental study of the physical properties associated with the heat transfer capacity of ZrO{sub 2} nanofluids in aqueous base and the effects of gamma on such properties, with a view to the possibility of applying as heat transfer fluid in future generations of nuclear reactor systems. The effects of concentrations and temperature, before and after the action of ionizing radiation were carried out. Theoretical models, parameters of influence and experimental results available in specialized literature were reviewed. Experimental study of physical properties of nanofluids samples in various concentrations (0.001% vol. 0.01% vol. 0.1% vol.), without the action of gamma radiation was also conducted. The physical properties investigated are the thermal conductivity, electrical conductivity, pH, density, and viscosity. Nanofluid samples were irradiated in the Multipurpose Radiator of IPEN under the doses 1 MGy, 2 MGy, and 3 MGy. Analysis using techniques of samples visualization before and after irradiation using scanning electron microscope (SEM) was adopted. The trials will be held to display the verification of the change in distribution of nanoparticles after irradiation of samples. This test aims to check for changes in the structure of the nanoparticles. It is expected with the results from this research project, a contribution to the advancement of knowledge of nanofluids applications in high heat transfer systems. (author)

  4. Interaction of a H2O/Ar Plasma Jet with Nitrogen Atmosphere: Effect of the Method for Calculating Thermophysical Properties of the Gas Mixture on the flow field

    Czech Academy of Sciences Publication Activity Database

    Agon, N.; Vierendeels, J.; Hrabovský, Milan; Murphy, A.B.; Van Oost, G.

    2015-01-01

    Roč. 35, č. 2 (2015), s. 365-386 ISSN 0272-4324 R&D Projects: GA ČR(CZ) GA15-19444S Institutional support: RVO:61389021 Keywords : Thermal plasma * Computational fluid dynamics * Thermophysical properties * Mixing rules * Ionized gas mixtures Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.811, year: 2015 http://link.springer.com/article/10.1007%2Fs11090-014-9605-6

  5. Influence of the Alkyl Side Chain Length on the Thermophysical Properties of Chiral Ionic Liquids with a (1R,2S,5R)-(–)-Menthol Substituent and Data Treatment by Means of Mathematical Gnostics.

    Czech Academy of Sciences Publication Activity Database

    Andresová, Adéla; Bendová, Magdalena; Schwarz, Jaroslav; Wagner, Zdeněk; Feder-Kubis, J.

    2017-01-01

    Roč. 242, SEP 2017 (2017), s. 336-348 ISSN 0167-7322 R&D Projects: GA MŠk(CZ) 7AMB14PL005 Grant - others:NSC(PL) 2011/01/B/ST5/06659 Institutional support: RVO:67985858 Keywords : chiral ionic liquid s * thermophysical properties * mathematical gnostics Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 3.648, year: 2016

  6. Influence of the Alkyl Side Chain Length on the Thermophysical Properties of Chiral Ionic Liquids with a (1R,2S,5R)-(–)-Menthol Substituent and Data Treatment by Means of Mathematical Gnostics.

    Czech Academy of Sciences Publication Activity Database

    Andresová, Adéla; Bendová, Magdalena; Schwarz, Jaroslav; Wagner, Zdeněk; Feder-Kubis, J.

    2017-01-01

    Roč. 242, SEP 2017 (2017), s. 336-348 ISSN 0167-7322 R&D Projects: GA MŠk(CZ) 7AMB14PL005 Grant - others:NSC(PL) 2011/01/B/ST5/06659 Institutional support: RVO:67985858 Keywords : chiral ionic liquids * thermophysical properties * mathematical gnostics Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 3.648, year: 2016

  7. Rheological and thermophysical properties of ultra-stable kerosene-based Fe3O4/Graphene nanofluids for energy conservation

    International Nuclear Information System (INIS)

    Askari, S.; Lotfi, R.; Rashidi, A.M.; Koolivand, H.; Koolivand-Salooki, M.

    2016-01-01

    Highlights: • Graphene-Fe 3 O 4 nanoparticles coated by oleic acid were synthesized. • Ultra-stable kerosene based nanofluid was produced from Graphene-Fe 3 O 4 nanohybrid. • Rheological and thermal properties of nanofluids were investigated. • Significant enhancement in thermal characteristics of nanofluid was observed. - Abstract: This research deals with a novel synthesis method for preparation of Fe 3 O 4 decorated Graphene and its application as a kerosene-based nanofluid with the purpose of heat transfer enhancement. In order to stabilize the Graphene-Fe 3 O 4 nanoparticles, oleic acid was grafted on the surface of nanoparticles by chemisorption. Synthesized nanohybrid was characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), Dynamic light scattering (DLS) and UV–Vis spectrophotometer. The nanofluid remains stable for more than five months without any sedimentation. Moreover, rheological and thermal properties of nanofluids were measured. Viscosity increment, especially in low concentrations of nanoparticles was negligible enough for industrial applications and density enhancement is completely negligible even in high concentrations. The thermal conductivity was improved 31% at 50 °C, compared to the base fluid. In order to examine convective heat transfer enhancement, an experimental setup was designed and measurements were examined in Reynolds numbers between 2166 and 4553. The maximum heat transfer enhancement was 66% at Reynolds number of 4553 and 0.3 wt.% of nanoparticle. Increase in particles loading and Reynolds number causes convective heat transfer coefficient to improve.

  8. Effect of water on the thermo-physical properties of Reline: An experimental and molecular simulation based approach.

    Science.gov (United States)

    Shah, Dhawal; Mjalli, Farouq S

    2014-11-21

    Increasing applications of ionic liquids and their analogues, namely Deep Eutectic Solvents (DESs), requires further investigation into the effect of moisture content on the physico-chemical characteristics of these fluids. Although it is common practice to synthesize these fluids in a moisture-controlled environment, as moisture is generally considered to have an impact on their properties, there are no systematic studies on this. We herein examine the effects of water on Reline, a Type-III DES composed of urea and choline chloride. Experiments were performed to obtain the physical properties of aqueous Reline solution. We observed moderate changes in density, speed of sound, refractive index, and pH with increasing water fraction; however, the change in viscosity and conductivity was strong and exponential. In addition, molecular dynamics simulations were performed to analyze the intermolecular interactions of Reline and aqueous Reline solutions. The simulations primarily present the significance of urea-anion interaction to explain the low melting point of the DES. In the presence of water, the anion is preferentially hydrated as compared to urea or the cation. More interestingly, simulations help to classify the effects of water into different regimes. At low water fractions (analysis. Beyond 25% water fractions, the components of Reline are individually hydrated and have high diffusivity, which is further reflected in the change in transport properties. The results presented herein provide valuable information on aqueous Reline solutions both in terms of experimental data and molecular insights, which in turn, we believe, might assist in developing further applications of Reline and other related DESs.

  9. Thermophysical study of methyl levulinate

    International Nuclear Information System (INIS)

    Lomba, Laura; Lafuente, Carlos; García-Mardones, Mónica; Gascón, Ignacio; Giner, Beatriz

    2013-01-01

    Highlights: • We have carried out a thermophysical characterization of methyl levulinate. • The study has been performed over a temperature range from (278.15 to 328.15) K. • pρT behavior has been studied over a temperature range from (333.15 to 453.15) K. • TRIDEN equation has been used to correlate pρT data. • Results have been compared with of ethyl and butyl levulinate and levulinic acid. -- Abstract: Several thermophysical properties (density, speed of sound, refractive index, surface tension, static permittivity and dynamic viscosity) of methyl levulinate have been measured under atmospheric pressure at temperatures from (278.15 to 338.15) K, while the vapor pressure was determined over a temperature range from (333.15 to 453.15) K. Furthermore, pρT behavior has been also investigated using a high-pressure, high-temperature vibrating tube densimeter over a temperature range from (283.15 to 338.15) K and a pressure range from (0.1 to 60.0) MPa. All these values obtained for methyl levulinate have been compared with other members of the levulinate family and also with levulinic acid

  10. On the thermophysical and transport properties of 3He and 4He: A bubble interaction potential versus state of the art

    Science.gov (United States)

    Chrysos, Michael; Piel, Henri

    2017-07-01

    Three keynote thermophysical and transport properties of 3He and 4He, namely, the second virial coefficient, the shear viscosity, and the thermal conductivity, are reported for the "extended Dirac bubble potential" (EDbp), a novel model for He-He [M. Chrysos, J. Chem. Phys. 146, 024106 (2017)]. Comparisons with the experiment as well as with potentials with a proven track record and with the oversimplified Dbp are being made in the range 0.1-500 K to analyze the performance of the EDbp, which is shown here to emerge as a promising analytic model for He-He. A flowchart of how to treat the "buffer" in scattering cross section measurements is designed and conducted, offering a route to EDbp optimization. An impressive consistency with state-of-the-art calculations (which is just striking for such a simple analytic model) is found, essentially thanks to the performance of the phase-shift expression cot δ l = /λ k r 0 ξ l y l ( k r 0 ) - y l ( k r c ) λ k r 0 ξ l j l ( k r 0 ) - j l ( k r c ) , ξ l = j l ( k r 0 ) y l ( k r c ) - j l ( k r c ) y l ( k r 0 ) . A Multimedia view of δ l ( k , r c ) versus k and rc is part of the material presented in this article. Data for the "best" rc(k) is given as a supplementary material.

  11. An Investigation on the Thermophysical Properties of a Binary Molten Salt System Containing Both Aluminum Oxide and Titanium Oxide Nanoparticle Suspensions

    Science.gov (United States)

    Giridhar, Kunal

    of nanoparticles and change in thermophysical properties of molten salt for various types of nanoparticles.

  12. Development of the system of reactor thermophysical data on the basis of ontological modelling

    Science.gov (United States)

    Chusov, I. A.; Kirillov, P. L.; Bogoslovskaya, G. P.; Yunusov, L. K.; Obysov, N. A.; Novikov, G. E.; Pronyaev, V. G.; Erkimbaev, A. O.; Zitserman, V. Yu; Kobzev, G. A.; Trachtengerts, M. S.; Fokin, L. R.

    2017-11-01

    Compilation and processing of the thermophysical data was always an important task for the nuclear industry. The difficulties of the present stage of this activity are explained by sharp increase of the data volume and the number of new materials, as well as by the increased requirements to the reliability of the data used in the nuclear industry. General trend in the fields with predominantly orientation at the work with data (material science, chemistry and others) consists in the transition to a common infrastructure with integration of separate databases, Web-portals and other resources. This infrastructure provides the interoperability, the procedures of the data exchange, storage and dissemination. Key elements of this infrastructure is a domain-specific ontology, which provides a single information model and dictionary for semantic definitions. Formalizing the subject area, the ontology adapts the definitions for the different database schemes and provides the integration of heterogeneous data. The important property to be inherent for ontologies is a possibility of permanent expanding of new definitions, e.g. list of materials and properties. The expansion of the thermophysical data ontology at the reactor materials includes the creation of taxonomic dictionaries for thermophysical properties; the models for data presentation and their uncertainties; the inclusion along with the parameters of the state, some additional factors, such as the material porosity, the burnup rate, the irradiation rate and others; axiomatics of the properties applicable to the given class of materials.

  13. Validation of Trimethylamine-N-oxide (TMAO) Force Fields Based on Thermophysical Properties of Aqueous TMAO Solutions.

    Science.gov (United States)

    Markthaler, Daniel; Zeman, Johannes; Baz, Jörg; Smiatek, Jens; Hansen, Niels

    2017-11-30

    Five molecular models for trimethylamine N-oxide (TMAO) to be used in conjunction with compatible models for liquid water are evaluated by comparison of molecular dynamics (MD) simulation results to experimental data as functions of TMAO molality. The experimental data comprise thermodynamic properties (density, apparent molar volume, and partial molar volume at infinite dilution), transport properties (self-diffusion and shear viscosity), structural properties (radial distribution functions and degree of hydrogen bonding), and dielectric properties (dielectric spectra and static permittivity). The thermodynamic and transport properties turned out to be useful in TMAO model discrimination while the influence of the water model and the TMAO-water interaction are effectively probed through the calculation of dielectric spectra.

  14. Rheological and thermophysical properties of blackberry juice Propriedades reológicas e termofísicas de suco de amora

    Directory of Open Access Journals (Sweden)

    Renato Alexandre Ferreira Cabral

    2007-09-01

    Full Text Available Rheological and thermophysical properties were determined for blackberry juice, which was produced from blackberry fruit at 9.1 ± 0.5 °Brix and density of 1.0334 ± 0.0043 g cm-3. The concentration process was performed using a roto evaporator, under vacuum, to obtain concentrated juice at about 60 °Brix. In order to obtain different concentrations, concentrated juice was diluted with distilled water. Rheological measurements were carried out using a Rheotest 2.1 Searle type rheometer. In the tested ranges, the samples behaved as pseudoplastic fluids, and the Power-Law model was satisfactorily fitted to the experimental data. The friction factor was measured for blackberry juice in laminar flow conditions of pseudoplastic behavior. Thermal conductivity, thermal diffusivity and density of blackberry juice at 9.4 to 58.4 °Brix were determined, in triplicate, at 0.5 to 80.8 °C. Polynomial regression was performed to fit experimental data obtaining a good fit. Both temperature and concentration showed a strong influence on thermophysical properties of blackberry juice. Calculated apparent specific heat values varied from 2.416 to 4.300 kJ.kg-1 °C in the studied interval.As propriedades reológicas e termofísicas foram determinadas para suco de amora produzido a partir da fruta com 9.1 ± 0.5 °Brix e densidade de 1,0334 ± 0,0043 g cm-3. O processo de concentração foi realizado utilizando-se um roto evaporador, sob vácuo, obtendo-se o suco concentrado em aproximadamente 60 °Brix. As diferentes concentrações foram obtidas a partir da diluição do suco concentrado em água destilada. As medidas reológicas foram conduzidas utilizando-se o reômetro Rheotest 2.1 do tipo Searle. Em todos os experimentos as amostras apresentaram um comportamento pseudoplástico, e o modelo da Lei da Potência foi ajustado satisfatoriamente aos dados experimentais. O fator de atrito foi medido para o suco em regime laminar com comportamento pseudopl

  15. Study of thermophysical and thermohydraulic properties of sodium for fast sodium cooled reactors; Estudio de las propiedades termofisicas y termohidraulicas del sodio para reactores rapidos enfriados por sodio

    Energy Technology Data Exchange (ETDEWEB)

    Vega R, A. K.; Espinosa P, G. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, San Rafael Atlixco No. 186, Col. Vicentina, 09340 Ciudad de Mexico (Mexico); Gomez T, A. M., E-mail: a.karen.vr@gmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2016-09-15

    The importance of liquid sodium lies in its use as a coolant for fast reactors, but why should liquid metal be used as a coolant instead of water? Water is difficult to use as a coolant for a fast nuclear reactor because its acts as a neutron moderator, that is, stop the fast neutrons and converts them to thermal neutrons. Nuclear reactors such as the Pressurized Water Reactor or the Boiling Water Reactor are thermal reactors, which mean they need thermal neutrons for their operation. However, is necessary for fast reactors to conserve as much fast neutrons, so that the liquid metal coolants that do have this capability are implemented. Sodium does not need to be pressurized, its low melting point and its high boiling point, higher than the operating temperature of the reactor, make it an adequate coolant, also has a high thermal conductivity, which is necessary to transfer thermal energy and its viscosity is close to that of the water, which indicates that is an easily transportable liquid and does not corrode the steel parts of the reactor. This paper presents a brief state of the art of the rapid nuclear reactors that operated and currently operate, as well as projects in the door in some countries; types of nuclear reactors which are cooled by liquid sodium and their operation; the mathematical models for obtaining the properties of liquid sodium in a range of 393 to 1673 Kelvin degrees and a pressure atmosphere. Finally a program is presented in FORTRAN named Thermo-Sodium for the calculation of the properties, which requires as input data the Kelvin temperature in which the liquid sodium is found and provides at the user the thermo-physical and thermo-hydraulic properties for that data temperature. Additional to this the user is asked the Reynolds number and the hydraulic diameter in case of knowing them, and in this way the program will provide the value of the convective coefficient and that of the dimensionless numbers: Nusselt, Prandtl and Peclet. (Author)

  16. Propriedades termofísicas de soluções-modelo similares a sucos: parte II Thermophysical properties of model solutions similar to juice: part II

    Directory of Open Access Journals (Sweden)

    Sílvia Cristina Sobottka Rolim de Moura

    2005-09-01

    Full Text Available Propriedades termofísicas, densidade e viscosidade de soluções-modelo similares a sucos foram determinadas experimentalmente. Os resultados foram comparados aos preditos por modelos matemáticos (STATISTICA 6.0 e obtidos da literatura em função da sua composição química. Para definição das soluções-modelo, foi realizado um planejamento estrela, mantendo-se fixa a quanti-dade de ácido (1,5% e variando-se a água (82-98,5%, o carboidrato (0-15% e a gordura (0-1,5%. A densidade foi determinada em picnômetro. A viscosidade foi determinada em viscosímetro Brookfield modelo LVF. A condutividade térmica foi calculada com o conhecimento das propriedades difusividade térmica e calor específico (apresentados na Parte I deste trabalho MOURA [7] e da densidade. Os resultados de cada propriedade foram analisados através de superfícies de respostas. Foram encontrados resultados significativos para as propriedades, mostrando que os modelos encontrados representam as mudanças das propriedades térmicas e físicas dos sucos, com alterações na composição e na temperatura.Thermophysical properties, density and viscosity of model solutions similar to juices were experimentally determined. The results were compared to those predicted by mathematical models (STATISTIC 6.0 and to values mentioned in the literature, according to the chemical composition. A star planning was adopted to define model solutions composition; fixing the acid amount in 1.5% and varying water (82-98.5%, carbohydrate (0-15% and fat (0-1.5%. The density was determined by picnometer. The viscosity was determined by Brookfield LVF model viscosimeter. The thermal conductivity was calculated based on thermal diffusivity and specific heat values (presented at the 1st . Part of this paper - MOURA [7] and density. The results of each property were analyzed by the response surface method. The found results were significant, indicating that the models represent the changes of

  17. Analysis of Influence of the Thermal Dependence of Air Thermophysical Properties on the Accuracy of Simulation of Heat Transfer in a Turbulent Flow in Case of Applying Different Methods of Averaging Navier-Stokes Equations

    Directory of Open Access Journals (Sweden)

    A. D. Kliukvin

    2014-01-01

    Full Text Available There is theoretically investigated the influence of thermal dependence of air thermophysical properties on accuracy of heat transfer problems solution in a turbulent flow when using different methods of averaging the Navier-Stokes equations.There is analyzed the practicability of using particular method of averaging the NavierStokes equations when it’s necessary to clarify the solution of heat transfer problem taking into account the variability of air thermophysical properties.It’s shown that Reynolds and Favre averaging (the most common methods of averaging the Navier-Stokes equations are not effective in this case because these methods inaccurately describe behavior of large scale turbulent structures which strongly depends on geometry of particular flow. Thus it’s necessary to use more universal methods of turbulent flow simulation which are not based on averaging of all turbulent scales.In the article it’s shown that instead of Reynold and Favre averaging it’s possible to use large eddy simulation whereby turbulent structures are divided into small-scale and large-scale ones with subsequent modelling of small-scale ones only. But this approach leads to the necessarity of increasing the computational power by 2-3 orders.For different methods of averaging the form of additional terms of averaged Navier-Stokes equations in case of accounting pulsation of thermophysical properties of the air is obtained.On the example of a submerged heated air jet the errors (which occur when neglecting the thermal dependence of air thermophysical properties on averaged flow temperature in determination of convectional and conductive components of heat flux and viscous stresses are evaluated. It’s shown that the greatest increase of solution accuracy can be obtained in case of the flows with high temperature gradients.Finally using infinite Teylor series it’s found that underestimation of convective and conductive components of heat flux and

  18. European Conference on Thermophysical Properties (11th) Held on 13-16 June 1988, University of Umea, Sweden. Abstracts

    Science.gov (United States)

    1988-06-16

    Nieto de Castro Universidade de Lisboa 42 Departemento de Quimica 63 Rua Ernesto de Vasconcelos Edificio C 1 1700 Lisboa PORTUGAL O Nilsson... ambient temperature. In this range, it has been experimentally found, for the first time, that the spectral radiative properties of ordinary fiberglasses...temperatures slightly above ambient . The transient hot strip (THS) method is very suitable for "instantaneous" determinations of the thermal

  19. Gas energy meter for inferential determination of thermophysical properties of a gas mixture at multiple states of the gas

    Science.gov (United States)

    Morrow, Thomas B [San Antonio, TX; Kelner, Eric [San Antonio, TX; Owen, Thomas E [Helotes, TX

    2008-07-08

    A gas energy meter that acquires the data and performs the processing for an inferential determination of one or more gas properties, such as heating value, molecular weight, or density. The meter has a sensor module that acquires temperature, pressure, CO2, and speed of sound data. Data is acquired at two different states of the gas, which eliminates the need to determine the concentration of nitrogen in the gas. A processing module receives this data and uses it to perform a "two-state" inferential algorithm.

  20. High temperature measurements and condensed matter analysis of the thermo-physical properties of ThO2.

    Science.gov (United States)

    Pavlov, T R; Wangle, T; Wenman, M R; Tyrpekl, V; Vlahovic, L; Robba, D; Van Uffelen, P; Konings, R J M; Grimes, R W

    2018-03-22

    Values are presented for thermal conductivity, specific heat, spectral and total hemispherical emissivity of ThO 2 (a potential nuclear fuel material) in a temperature range representative of a nuclear accident - 2000 K to 3050 K. For the first time direct measurements of thermal conductivity have been carried out on ThO 2 at such high temperatures, clearly showing the property does not decrease above 2000 K. This could be understood in terms of an electronic contribution (arising from defect induced donor/acceptor states) compensating the degradation of lattice thermal conductivity. The increase in total hemispherical emissivity and visible/near-infrared spectral emissivity is consistent with the formation of donor/acceptor states in the band gap of ThO 2 . The electronic population of these defect states increases with temperature and hence more incoming photons (in the visible and near-infrared wavelength range) can be absorbed. A solid state physics model is used to interpret the experimental results. Specific heat and thermal expansion coefficient increase at high temperatures due to the formation of defects, in particular oxygen Frenkel pairs. Prior to melting a gradual increase to a maximum value is predicted in both properties. These maxima mark the onset of saturation of oxygen interstitial sites.

  1. Rheological and thermophysical properties of carragenan and β-lactoglobulin model systems treated with high hydrostatic pressure

    Directory of Open Access Journals (Sweden)

    Edita Juraga

    2006-03-01

    Full Text Available The aim of this paper is to examine the influence of high hydrostatic pressure treatment on the rheological and thermophisical properties of β-lactoglobulin and carragenan model systems. Suspensions of β-lactoglobulin were treated with a high hydrostatic pressure in a range of 300 to 600 MPa. Holding period was 5 and 10 minutes.Measurements were performed using rotational viscosimeter Rheometric Scientific RM-180 at 20 oC. The rheological parameters were determined by the Ostwald de Waele law. The results of the investigation have shown that all investigated systems are non-Newtonian – pseudoplastic. All samples treated with high hydrostatic pressure have changed rheological characteristics. The extent of protein denaturation was proportional to the intensity of applied pressure and holding time. The phase transition temperatures were determined by differential thermal analysis (DTA. High pressure treatment caused depression of freezing point and melting point, respectively. Carragenan acts as a crioprotectant.

  2. MICROSTRUCTURE, THERMO-PHYSICAL, MECHANICAL AND WEAR PROPERTIES OF IN-SITU FORMED BORON CARBIDE - ZIRCONIUM DIBORIDE COMPOSITE

    Directory of Open Access Journals (Sweden)

    T. S. R. Ch. Murthy

    2017-12-01

    Full Text Available Microstructure, thermos-physical, mechanical and wear properties of in-situ formed B₄C- ZrB₂ composite were investigated. Coefficient of thermal expansion, thermal diffusivity and electrical resistivity of the composite were measured at different temperatures up to 1000 °C in inert atmosphere. Flexural strength was measured up to 900 °C in air. Friction and wear properties have been studied at different loads under reciprocative sliding, using a counter body (ball of cemented tungsten carbide (WC-Co at ambient conditions. X-ray diffraction (XRD and electron probe microanalysis (EPMA confirmed the formation of ZrB₂ as the reaction product in the composite. Electrical resistivity was measured as 3.02 x 10-4Ω.m at 1000°C. Thermal conductivity measured at temperatures between 25°C and 1000 °C was in the range of 8 to 10 W/m-K. Flexural strength of the composite decreased with increase in temperature and reached a value of 92 MPa at 900°C. The average value of coefficient of friction (COF was measured as 0.15 at 20 N load and 10 Hz frequency. Increase of load from 5 N to 20 N resulted in decrease in COF from 0.24 to 0.15 at 10 Hz frequency. Specific wear rate data observed was of the order of 10-6 mm³/N-m. Both abrasive and tribo-chemical reaction wear mechanisms were observed on the worn surface of flat and counter body materials. At higher loads (≥10 N a tribo-chemical reaction wear mechanism was dominant.

  3. Thermophysical Properties of Acetophenone with Ethylchloroacetate at Temperatures of 303.15, 313.15 and 323.15 K

    International Nuclear Information System (INIS)

    Saravanakumar, K.; Baskaran, R.; Kubendran, T. R.

    2012-01-01

    Densities, viscosities, refractive indices and speed of sounds of the binary mixtures of Acetophenone with Ethylchloroacetate were measured over the entire mole fractions at (303.15, 313.15 and 323.15) K. From these experimental results, excess molar volume V E , viscosity deviation Δη, refractive index deviation Δn D , deviations in speed of sound Δu, deviations in isentropic compressibility Δk s and excess intermolecular free length ΔL f were calculated. The viscosity data have been correlated with the equations of Grunberg and Nissan, Hind et al., Tamura and Kurata, Katti and Chaudri, Sedgwick, Krishnan-Laddha and McAllister. The thermo physical properties under study were fit to the Jouyban-Acree model. The excess values were correlated using Redlich-Kister polynomial equation to obtain their coefficients and standard deviations. It was found that in all cases, the data obtained fitted with the values correlated by the corresponding models very well. The results are interpreted in terms of molecular interactions occurring in the solution

  4. Thermophysical properties of {(±)-linalool + propan-1-ol}: A first stage towards the development of a green process

    International Nuclear Information System (INIS)

    Garcia-Abarrio, Sandra M.; Torcal, Marcos; Haya, M. Luisa; Urieta, Jose S.; Mainar, Ana M.

    2011-01-01

    Research highlights: → Optimization of supercritical processes needs adequate methods to reproduce the phase behavior. → ρ, u, n D and related properties of the system linalool+propan-1-ol were studied. → Collision Factor (u), Lorentz-Lorenz and Gladstone -Dale (n D ) give the best results. → Peng-Robinson, Patel-Teja, SAFT and PC-SAFT were tested as predictive PρT models. → PC-SAFT provides the best PρT prediction (20-40 MPa) with an AAD% of 0.83. - Abstract: In this paper, densities, speeds of sound and refractive indexes of binary mixture of {(±)-linalool (1) + propan-1-ol (2)} at four temperatures (283.15, 298.15, 313.15, and 328.15) K and 0.1 MPa are reported over the whole composition range. These data were used to calculate excess molar volume, speed of sound deviation, excess isentropic compressibility, refractive index deviation, molar refraction, and molar refraction deviation at the four work temperatures. All magnitudes were fitted to the Redlich-Kister equation. Subsequently prediction of speed of sound and refractive index was carried out using several theoretical models or equations. On the other hand, the density of the same mixture was determined in the same temperature range at pressures from 20 MPa to 40 MPa. Four equation of state (Peng-Robinson, Patel-Teja, SAFT, PC-SAFT) were tested as predictive models of the PρT behavior. The best results were obtained by PC-SAFT, with an average absolute deviation of 0.83%.

  5. Thermodynamic and Microstructural Mechanisms in the Corrosion of Advanced Ceramic Tc-bearing Waste Forms and Thermophysical Properties

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Thomas [Univ. of Nevada, Las Vegas, NV (United States). Dept. of Mechanical Engineering

    2017-09-01

    Technetium-99 (Tc, t1/2 = 2.13x105 years) is a challenge from a nuclear waste perspective and is one of the most abundant, long-lived radioisotopes found in used nuclear fuel (UNF). Within the Hanford Tank Waste Treatment and Immobilization Plant, technetium volatilizes at typical glass melting temperature, is captured in the off-gas treatment system and recycled back into the feed to eventually increase Tc-loadings of the glass. The aim of this NEUP project was to provide an alternative strategy to immobilize fission technetium as durable ceramic waste form and also to avoid the accumulation of volatile technetium within the off gas melter system in the course of vitrifying radioactive effluents in a ceramic melter. During this project our major attention was turned to the fabrication of chemical durable mineral phases where technetium is structurally bond entirely as tetravalent cation. These mineral phases will act as the primary waste form with optimal waste loading and superior resistance against leaching and corrosion. We have been very successful in fabricating phase-pure micro-gram amounts of lanthanide-technetium pyrochlores by dry-chemical synthesis. However, upscaling to a gram-size synthesis route using either dry- or wet-chemical processing was not always successful, but progress can be reported on a variety of aspects. During the course of this 5-year NEUP project (including a 2-year no-cost extension) we have significantly enhanced the existing knowledge on the fabrication and properties of ceramic technetium waste forms.

  6. Effect of Blend Ratio on Thermo-Physical and Sensory ...

    African Journals Online (AJOL)

    Thermo-physical properties of bread made from wheat, cassava and soybean blends were investigated. During investigation, the organoleptic acceptance of the composite wheat, cassava and soy bread was determined. All the blend ratios were exposed to equal heating rate during baking at set temperature of 230oC. The ...

  7. Comparison of Approaches for Measuring the Mass Accommodation Coefficient for the Condensation of Water and Sensitivities to Uncertainties in Thermophysical Properties

    Science.gov (United States)

    2012-01-01

    We compare and contrast measurements of the mass accommodation coefficient of water on a water surface made using ensemble and single particle techniques under conditions of supersaturation and subsaturation, respectively. In particular, we consider measurements made using an expansion chamber, a continuous flow streamwise thermal gradient cloud condensation nuclei chamber, the Leipzig Aerosol Cloud Interaction Simulator, aerosol optical tweezers, and electrodynamic balances. Although this assessment is not intended to be comprehensive, these five techniques are complementary in their approach and give values that span the range from near 0.1 to 1.0 for the mass accommodation coefficient. We use the same semianalytical treatment to assess the sensitivities of the measurements made by the various techniques to thermophysical quantities (diffusion constants, thermal conductivities, saturation pressure of water, latent heat, and solution density) and experimental parameters (saturation value and temperature). This represents the first effort to assess and compare measurements made by different techniques to attempt to reduce the uncertainty in the value of the mass accommodation coefficient. Broadly, we show that the measurements are consistent within the uncertainties inherent to the thermophysical and experimental parameters and that the value of the mass accommodation coefficient should be considered to be larger than 0.5. Accurate control and measurement of the saturation ratio is shown to be critical for a successful investigation of the surface transport kinetics during condensation/evaporation. This invariably requires accurate knowledge of the partial pressure of water, the system temperature, the droplet curvature and the saturation pressure of water. Further, the importance of including and quantifying the transport of heat in interpreting droplet measurements is highlighted; the particular issues associated with interpreting measurements of condensation

  8. Ab initio calculation of the interaction potentials of helium, neon, and methane as well as theoretical studies on their thermophysical properties and those of water vapor; Ab initio-Berechnung der Wechselwirkungspotentiale von Helium, Neon und Methan sowie theoretische Untersuchungen zu ihren thermophysikalischen Eigenschaften und denen von Wasserdampf

    Energy Technology Data Exchange (ETDEWEB)

    Hellmann, Robert

    2009-06-16

    Thermophysical properties of the pure gases helium, neon, methane and water vapor were calculated for low densities over wide temperature ranges. Statistical thermodynamics was used for the determination of the pressure virial coefficients. The kinetic theory of gases was utilized for the calculation of the transport and relaxation properties. So far kinetic theory was limited to linear molecules and has now been extended to molecules of arbitrary geometry to enable calculations on methane and water vapor. The interaction potentials, which are needed for all computations, were determined for helium, neon and methane from the supermolecular approach using quantum chemical ab initio methods. For water the interaction potentials were taken from the literature. The calculated values of the thermophysical properties for the four gases show very good agreement with the best experimental data. At very low and very high temperatures the theoretical values are more accurate than experimental data. (orig.)

  9. A thermophysical battery for storage-based climate control

    International Nuclear Information System (INIS)

    Narayanan, Shankar; Kim, Hyunho; Umans, Ari; Yang, Sungwoo; Li, Xiansen; Schiffres, Scott N.; Rao, Sameer R.; McKay, Ian S.; Rios Perez, Carlos A.; Hidrovo, Carlos H.; Wang, Evelyn N.

    2017-01-01

    Highlights: • The concept of a thermophysical battery for storing thermal energy is demonstrated. • The battery provides heating and cooling for stationary and mobile applications. • Energy storage mechanisms: adsorption-desorption and evaporation-condensation. • Max. heating: 103 W/l and 65 W/kg; Max. Cooling: 78 W/l and 49 W/kg. • Novel adsorbents further enhance performance for a compact and lightweight system. - Abstract: Climate control applications in the form of heating and cooling account for a significant portion of energy consumption in buildings and transportation. Consequently, improved efficiency of climate control systems can significantly reduce the energy consumption and greenhouse gas emissions. In particular, by leveraging intermittent or continuous sources of waste heat and solar energy, thermally-driven energy storage systems for climate control can play a crucial role. We demonstrate the concept of a thermophysical battery, which operates by storing thermal energy and subsequently releasing it to provide heating and cooling on demand. Taking advantage of the adsorption-desorption and evaporation-condensation mechanisms, the thermophysical battery can be a high-power density and rechargeable energy storage system. We investigated the thermophysical battery in detail to identify critical parameters governing its overall performance. A detailed computational analysis was used to predict its cyclic performance when exposed to different operating conditions and thermodynamic cycles. In addition, an experimental test bed was constructed using a contemporary adsorptive material, NaX-zeolite, to demonstrate this concept and deliver average heating and cooling powers of 900 W and 650 W, respectively. The maximum power densities and specific powers observed were 103 W/l and 65 W/kg for heating, and 78 W/l and 49 W/kg for cooling, respectively, making the thermophysical battery competitive with the state-of-the-art climate control systems that

  10. Thermophysical Analysis of Rocks by Transient Methods

    Science.gov (United States)

    Kubicar, Ludovit; Vretenar, Viliam; Bohac, Vlastimil; Stofanik, Vladimir; Dieska, Peter

    2010-05-01

    Rocks belong to porous materials where content of pore significantly influence its thermophysical properties. Porous structure plays an important role in heat and fluid transport. A set of effects can be found in such structures like freezing, thawing, evaporation, etc. Highly innovative testing technique based on transient methods has been used for thermophysical analysis in which the specific heat, thermal diffusivity and thermal conductivity is determined, anomalies of the thermophysical parameters connected with freezing and thawing of water in pores are measured, propagation of freezing and thawing fronts are detected and diffusion of moisture in pore structure is monitored on sandstone and Gioia marble. Pulse transient method is based on generation of a heat disturbance by plane heat source fixed in the sample. Specific heat, thermal diffusivity and thermal conductivity are determined from the parameters of the temperature response to this heat disturbance. A heat source in the step-wise heating regime was applied to the frozen sample to study basic characteristics of the propagation of thawing front. In both experiments a sample is used that consists of three parts of size 50x50x10 mm assembled in a rectangle 50x50x30 mm where in first contact of the specimen parts a plane of heat source and in the second one a thermometer is fixed. The sample has to be conditioned prior the measurement to obtain the required thermodynamic state, i.e. the initial temperature and moisture stage. An appropriate heating and cooling regime allows measuring the anomalies of specific heat, thermal conductivity and thermal diffusivity connected with freezing and thawing. The hot ball transient method for measuring thermal conductivity is used for monitoring the moisture diffusion. Principle of the hot ball method is based on generation of the heat in a step-wise regime by a sensor in a form of small ball in diameter of 2 mm that, in addition, it monitors its temperature. A

  11. Application of differential scanning calorimetry to estimate quality and nutritional properties of food products.

    Science.gov (United States)

    Parniakov, Oleksii; Bals, Olivier; Barba, Francisco J; Mykhailyk, Viacheslav; Lebovka, Nikolai; Vorobiev, Eugene

    2018-02-11

    Over the past years, both food researchers and food industry have shown an increased interest in finding techniques that can estimate modifications in quality, nutritional, and thermophysical properties of food products during processing and/or storage. For instance, differential scanning calorimetry (DSC) has attracted the interest of scientific community because only a small amount of sample is needed for analysis. Moreover, it does not require any specific sample preparation, and is a repeatable and reliable method. In addition, DSC methodology needs a short time for experiments compared with other techniques used for the same purpose. At this stage of investigation, there is a need to evaluate the commonly accepted and new emerging DSC applications to establish the optimum conditions of emerging processing. This paper reviews the current and new insights of DSC technique for the estimation of quality, nutritional, and thermophysical properties of food products during conventional and emerging processing and/or subsequent storage. The estimation of different properties in several food matrices after processing and/or storage is also discussed.

  12. Thermophysical Properties of Cold and Vacuum Plasma Sprayed Cu-Cr-X Alloys, NiAl and NiCrAlY Coatings. Part 1; Electrical and Thermal Conductivity, Thermal Diffusivity, and Total Hemispherical Emissivity

    Science.gov (United States)

    Raj, S. V.

    2017-01-01

    This two-part paper reports the thermophysical properties of several cold and vacuum plasma sprayed monolithic Cu and Ni-based alloy coatings. Part I presents the electrical and thermal conductivity, thermal diffusivity, and total hemispherical emissivity data while Part II reports the specific heat capacity data for these coatings. Metallic copper alloys, stoichiometric NiAl and NiCrAlY coatings were fabricated by either the cold sprayed or the vacuum plasma spray deposition processes for thermal property measurements between 77 and 1223 K. The temperature dependencies of the thermal conductivities, thermal diffusivities, electrical conductivities and total hemispherical emissivities of these cold and vacuum sprayed monolithic coatings are reported in this paper. The electrical and thermal conductivity data correlate reasonably well for Cu-8%Cr-1%Al, Cu-23%Cr-5%Al and NiAl in accordance with the Wiedemann-Franz (WF) law although a better fit is obtained using the Smith-Palmer relationship. The Lorentz numbers determined from the WF law are close to the theoretical value.

  13. Thermophysical study of 1,4-dioxane with cycloalkane mixtures

    International Nuclear Information System (INIS)

    Romero, C.; Giner, B.; Haro, M.; Artigas, H.; Lafuente, C.

    2006-01-01

    Densities, refractive indices, and surface tension for the binary mixtures 1,4-dioxane with cyclopentane or cylohexane have been determined at ambient pressure and at T = (283.15, 298.15, and 313.15) K. Excess volumes and refractive index and surface tension deviations have been calculated from the experimental data. Several relations between the thermophysical properties studied here have been tested using our experimental results

  14. Diamond electronic properties and applications

    CERN Document Server

    Kania, Don R

    1995-01-01

    The use of diamond in electronic applications is not a new idea, but limitations in size and control of properties restricted the use of diamond to a few specialised applications. The vapour-phase synthesis of diamond, however, has facilitated serious interest in the development of diamond-based electronic devices. The process allows diamond films to be laid down over large areas. Both intrinsic and doped diamond films have a unique combination of extreme properties for high speed, high power and high temperature applications. The eleven chapters in Diamond: Electronic Properties and Applications, written by the world's foremost experts on the subject, give a complete characterisation of the material, in both intrinsic and doped forms, explain how to grow it for electronic applications, how to use the grown material, and a description of both passive and active devices in which it has been used with success. Diamond: Electronic Properties and Applications is a compendium of the available literature on the sub...

  15. Development of measurement capabilities for the thermophysical properties of energy-related fluids. Annual report, December 1, 1992--November 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Kayser, R.F.

    1993-08-13

    The measurement capabilities to be developed include new apparatus for transport properties, thermodynamic properties, phase equilibria, and dielectric properties. Specific capabilities are: Thermal conductivity apparatus, vibrating wire viscometer, dual-sinker densimeter, high-temperature vibrating tube densimeter, dynamic phase equilibria apparatus, apparatus for dilute solutions, total-enthalpy flow calorimeter. Benchmark measurements were made (no data given) on pure and mixed alternative refrigerants and their mixtures with lubricants, and other fluids.

  16. REFRIGERANT/LUBRICANT MIXTURES: PROBLEMS OF APPLICATION AND PROPERTY RESEARCH

    Directory of Open Access Journals (Sweden)

    Yu. Semenyuk

    2013-10-01

    Full Text Available The results and generalizations of thermophysical property research for the refrigerant/lubricant mixtures are summarized. The methodological aspects of the experimental studies of the thermal properties of real working media for vapor compression refrigeration machines and the general principles of the thermodynamic properties simulation for such solutions are analyzed. It is shown that the admixtures of compressor oil in the refrigerant make the efficiency parameters of compressor systems much lower. The question of a selective solubility of the multicomponent refrigerants in compressor oils is discussed.

  17. Thermophysical Analysis of 101955 Bennu with OSIRIS-REx

    Science.gov (United States)

    Emery, Joshua; Rozitis, Ben; Christensen, Philip R.; Thomas, Cristina A.; Hamilton, Victoria E.; Clark, Beth Ellen; Delbo, Marco; Lim, Lucy F.; Lauretta, Dante

    2017-10-01

    NASA’s OSIRIS-REx mission will approach its target asteroid, (101955) Bennu, in August 2018. The primary objective of the mission is to return a pristine sample from Bennu in order to address some of NASA’s (and humanity’s) fundamental questions: How did the Solar System form? How did life evolve in the Solar System? Are asteroids harbingers of life or death - or both? Prior to picking up the sample from the surface, OSIRIS-REx will spend more than a year characterizing the surface with cameras, spectrometers, and the laser altimeter that are on board the spacecraft. Global and local determination of thermophysical properties will inform maps of sampleability, spacecraft safety, and science value of the surface. The primary data set to be used for thermophysical analyses are thermal spectra from the OSIRIS-REx Thermal Emission Spectrometer (OTES). The long-wavelength end of spectra obtained by the OSIRIS-REx Visible and InfraRed Spectrometer (OVIRS) will also be dominated by thermal emission. Full-disk observations during Approach will provide hemispherically averaged, but rotationally resolved, properties. The Approach observations also enable direct comparisons to previous Spitzer space telescope observations of Bennu. During the Detailed Survey phase, OTES will measure the infrared radiation from the entire surface, enabling us to map temperatures over Bennu at seven different local times of day (3:20am, 6am, 10am, 12:30pm, 3pm, 6pm, and 8:40pm). The diurnal temperature curves will be used to map the thermal inertia of the surface at a ~40m spatial scale. The Orbital phase of the mission will enable higher spatial resolution thermal observations of up to twelve potential sample sites, and Reconnaissance phase will enable even higher spatial resolution observations of the two highest priority potential sample sites. Thermophysical analysis of these data will be carried out with a custom thermal model that is based on the Advanced Thermophysical Model of

  18. Thermophysical and Microwave Shielding Properties of La0.5Sr0.5CoO3- δ and its Composite with Epoxy

    Science.gov (United States)

    Dijith, Kesavapillai Sreedeviamma; Pillai, Saju; Surendran, Kuzhichalil Peethambharan

    2017-08-01

    The microwave shielding properties of the perovskite oxide conductors, La0.5Sr0.5CoO3- δ (LSCO), were investigated. The sintered LSCO sheets were showing excellent microwave shielding properties up to 35-42 dB in the entire X and Ku bands. Towards getting a light-weight and easily processable structure, an attempt was made to composite LSCO with the easily mouldable polymer, epoxy. The thermal, dielectric and electromagnetic wave shielding properties of the composites were studied. The mechanical strength, thermal expansivity and thermal conductivity of the composites were progressively improved with LSCO addition. An improvement in the shielding effectiveness was observed with filler addition and attained a value of 10 dB in the range of 8.2-10 GHz for a maximum loaded LSCO-epoxy composite and the value spans from 3 dB to 9 dB in the Ku band region. The improvement in the shielding effectiveness with filler addition was supplemented by the gradual improvement in the dielectric permittivity, dielectric loss and AC conductivity.

  19. Thermophysical and radiation properties of high-temperature C4F8-CO2 mixtures to replace SF6 in high-voltage circuit breakers

    Science.gov (United States)

    Zhong, Linlin; Cressault, Yann; Teulet, Philippe

    2018-03-01

    C4F8-CO2 mixtures are one of the potential substitutes to SF6 in high-voltage circuit breakers. However, the arc quenching ability of C4F8-CO2 mixtures is still unknown. In order to provide the necessary basic data for the further investigation of arc quenching performance, the compositions, thermodynamic properties, transport coefficients, and net emission coefficients (NEC) of various C4F8-CO2 mixtures are calculated at temperatures of 300-30 000 K in this work. The thermodynamic properties are presented as the product of mass density and specific heat, i.e., ρCp. The transport coefficients include electrical conductivity, viscosity, and thermal conductivity. The atomic and molecular radiation are both taken into account in the calculation of NEC. The comparison of the properties between SF6 and C4F8-CO2 mixtures is also discussed to find their differences. The results of compositions show that C4F8-CO2 mixtures have a distinctive advantage over other alternative gases e.g., CF3I and C3F8, because the dissociative product (i.e., C4F6) of C4F8 at low temperatures has a very high dielectric strength. This is good for an arc quenching medium to endure the arc recovery phase. Compared with SF6, C4F8-CO2 mixtures present lower ρCp at temperatures below 2800 K and larger thermal conductivity above 2800 K. Based on the position of peaks in thermal conductivity, we predict that the cooling of C4F8-CO2 arc will be slowed down at higher temperatures than that of SF6 arc. It is also found that the mixing of CO2 shows slight effects on the electrical conductivity and NEC of C4F8-CO2 mixtures.

  20. Thermophysical and thermodynamic properties of ionic liquids over an extended pressure range: [bmim][NTf2] and [hmim][NTf2

    International Nuclear Information System (INIS)

    Gomes de Azevedo, R.; Esperanca, J.M.S.S.; Szydlowski, J.; Visak, Z.P.; Pires, P.F.; Guedes, H.J.R.; Rebelo, L.P.N.

    2005-01-01

    The current study focuses on 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide, [bmim][NTf 2 ], and 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide, [hmim][NTf 2 ]. The objective is to study the influence of pressure as well as that of the cation's alkyl chain length on several properties of this type of ionic liquids. Speed of propagation of ultrasound waves and densities in pure ionic liquids (ILs) as a function of temperature and pressure have been determined. Several other thermodynamic properties such as compressibilities, expansivities and heat capacities have been obtained. Speed of sound measurements have been carried out in broad ranges of temperature (283 < T/K < 323) and pressure (0.1 < p/MPa < 150), using a non-intrusive microcell. Density measurements have been performed at broad ranges of temperature (298 < T/K < 333) and pressure (0.1 < p/MPa < 60) using a vibrating tube densimeter. The pressure dependence of heat capacities, which is generally mild, is highly dependent on the curvature of the temperature dependence of density

  1. Nanofiber Manufacture, Properties, and Applications

    International Nuclear Information System (INIS)

    Lin, T.; Lukas, D.; Bhat, G.S.

    2013-01-01

    Nano fibers have shown many unique characteristics and enormous application potential in widely diverse areas. While considerable research has been conducted on exploring the properties and applications of nano fibers over the decade, the technology development for large-scale production of nano fibers has been hampered, which slows down the wide applications of nano fibers in practice. This special issue focuses on the recent progress in emerging nano fiber production techniques, such as needle less electro spinning, and novel properties and applications of nano fibers. It also covers unusual methods to process natural materials into nano fibrous materials. The special issue consists of four review articles and eighteen research papers. One review paper presents an overview of the recent developments in needle less electro spinning and the influences of needle less spinnerets on electro spinning process, nano fiber quality and productivity. The review also points out the challenges remaining for further research in this area. Other three reviews separately summarize the preparation, characterization and applications of ZnO nano wires and the applications of carbon nano fibers for neural electrical/chemical interfaces and for cement reinforcement. The research articles report new results of needle less electro spinning techniques, and novel methods to make bi component nano fibers, porous nano fibers, nano fiber hydrogel and chitin nan ofibrils. As Guest Editors for this special issue, we are pleased to see the progress in the applications of nano fibers, especially for sound absorption and for protective clothing, as well as the antibacterial properties of titanate nano fibers. We hope this special issue will promote further development of large-scale economically feasible nano fiber-making technologies, and also contribute to the wide use of nano fibers. We also hope that the articles collected in this special issue are well-received by the reader.

  2. Phosphorene: Fabrication, Properties, and Applications.

    Science.gov (United States)

    Kou, Liangzhi; Chen, Changfeng; Smith, Sean C

    2015-07-16

    Phosphorene, the single- or few-layer form of black phosphorus, was recently rediscovered as a two-dimensional layered material holding great promise for applications in electronics and optoelectronics. Research into its fundamental properties and device applications has since seen exponential growth. In this Perspective, we review recent progress in phosphorene research, touching upon topics on fabrication, properties, and applications; we also discuss challenges and future research directions. We highlight the intrinsically anisotropic electronic, transport, optoelectronic, thermoelectric, and mechanical properties of phosphorene resulting from its puckered structure in contrast to those of graphene and transition-metal dichalcogenides. The facile fabrication and novel properties of phosphorene have inspired design and demonstration of new nanodevices; however, further progress hinges on resolutions to technical obstructions like surface degradation effects and nonscalable fabrication techniques. We also briefly describe the latest developments of more sophisticated design concepts and implementation schemes that address some of the challenges in phosphorene research. It is expected that this fascinating material will continue to offer tremendous opportunities for research and development for the foreseeable future.

  3. Monte Carlo simulation of some thermophysical properties of two-centre Lennard-Jones fluids along the vapour-liquid equilibrium curve

    Science.gov (United States)

    Kronome, Gergely; Liszi, Janos; Szalai, Istvan

    The vapour pressures, saturated liquid and vapour densities, enthalpies of vaporization, isobaric, and saturation heat capacities are calculated for ethane and ethylene along their vapour-liquid equilibrium (VLE) curves from Monte Carlo simulations using the extended NpT plus test particle (XNpT + TP) method (Boda, D., Liszi, J., and Szalai, I., 1995, Chem. Phys. Lett. , 235, 140). The substances are modelled by two-centre Lennard-Jones molecules of elongations L * = 0.67 for ethane and L * = 0.74 for ethylene. Simulation results are compared with correlated experimental data. In the case of ethylene new values are required for the model parameters to obtain a good agreement with experimental data along the VLE curve. Our results show that the XNpT + TP method is appropriate for the simulation of caloric properties of molecular fluids along the VLE curve.

  4. Thermophysical properties of the binary mixtures (1,8-cineole + 1-alkanol) at T = (298.15 and 313.15) K and at atmospheric pressure

    Energy Technology Data Exchange (ETDEWEB)

    Alfaro, P.; Langa, E.; Martinez-Lopez, J.F.; Urieta, J.S. [Aragon Institute of Engineering Research (I3A, University of Zaragoza), 50009-Zaragoza (Spain); Mainar, A.M., E-mail: ammainar@unizar.e [Aragon Institute of Engineering Research (I3A, University of Zaragoza), 50009-Zaragoza (Spain)

    2010-02-15

    This work presents the measurements of the density, speed of sound, refractive index and enthalpy of binary mixtures containing left brace1,8-cineole + 1-alkanol (ethanol, 1-propanol, 1-butanol, and 1-pentanol)right brace at two temperatures (298.15 and 313.15) K and atmospheric pressure. The determination of excess molar volume, speed of sound deviation, refractive index deviation, molar refraction, molar refraction deviation, excess isentropic compressibility, and excess molar enthalpy are also given. Redlich-Kister equation was used to fit these derivate properties. The experimental data of the constituent binaries were analysed to discuss the nature and strengths of intermolecular interactions. Eventually some models, SAFT and PC-SAFT for density, Free Length and Collision Factor for speed of sound, Gladstone-Dale Arago-Biot for refractive index, and UNIFAC for excess molar enthalpy, among others, were successfully applied.

  5. PROPRIEDADES TERMOFÍSICAS DE SOLUÇÕES MODELO SIMILARES A CREME DE LEITE THERMOPHYSICAL PROPERTIES OF MODEL SOLUTIONS SIMILAR TO CREAM

    Directory of Open Access Journals (Sweden)

    Silvia Cristina Sobottka Rolim de MOURA

    2001-08-01

    Full Text Available A demanda de creme de leite UHT tem aumentado significativamente. Diversas empresas diversificaram e aumentaram sua produção, visto que o consumidor, cada vez mais exigente, almeja cremes com ampla faixa de teor de gordura. O objetivo do presente trabalho foi determinar a densidade, viscosidade aparente e difusividade térmica, de soluções modelo similares a creme de leite, na faixa de temperatura de 30 a 70°C, estudando a influência do teor de gordura e da temperatura nas propriedades físicas dos produtos. O delineamento estatístico aplicado foi o planejamento 3X5, usando níveis de teor de gordura e temperatura fixos em 15%, 25% e 35%; 30°C, 40°C, 50°C, 60°C e 70°C, respectivamente (STATISTICA 6.0. Manteve-se constante a quantidade de carboidrato e de proteína, ambos em 3%. A densidade foi determinada pelo método de deslocamento de fluidos em picnômetro; a difusividade térmica com base no método de Dickerson e a viscosidade aparente foi determinada em reômetro Rheotest 2.1. Os resultados de cada propriedade foram analisados através de método de superfície de resposta. No caso destas propriedades, os dados obtidos apresentaram resultados significativos, indicando que o modelo representou de forma confiável a variação destas propriedades com a variação da gordura (% e da temperatura (°C.The requirement of UHT cream has been increased considerably. Several industries varied and increased their production, since consumers, more and more exigent, are demanding creams with a wide range of fat content. The objective of the present research was to determine the density, viscosity and thermal diffusivity of model solutions similar to cream. The range of temperature varied from 30°C to 70°C in order to study the influence of fat content and temperature in the physical properties of cream. The statistic method applied was the factorial 3X5 planning, with levels of fat content and temperature fixed in 15%, 25% and 35%; 30

  6. Microstructure, thermophysical and electrical properties in AlxCoCrFeNi (0 ≤ x ≤2) high-entropy alloys

    International Nuclear Information System (INIS)

    Chou, H.-P.; Chang, Y.-S.; Chen, S.-K.; Yeh, J.-W.

    2009-01-01

    Al x CoCrFeNi (0 ≤ x ≤2) alloys were prepared by an arc remelter and investigated. With increasing x, the Al x CoCrFeNi alloys change from single FCC phase to single BCC phase with a transition duplex FCC/BCC region. The weak X-ray diffraction intensities indicate severe X-ray scattering effect of lattice in these high-entropy alloys. Electrical conductivity and thermal conductivity much smaller than those of pure component metals is ascribed as due to this lattice effect. The behavior of electrical conductivity and thermal conductivity can be divided into three parts according to microstructure. Both values of electrical conductivity and thermal conductivity decrease with increasing x in single-phase regions. Values of electrical conductivity and thermal conductivity are even higher than those in the duplex phase region because of the additional scattering effect of FCC/BCC phase boundaries in the alloys. Relative contribution of electron and phonon to electrical resistivity and thermal conductivity is evaluated in this study. It is shown that both electron and phonon components are comparable in these high-entropy alloys, and their transport properties are similar to that of semi-metal.

  7. Thermophysical properties of {l_brace}({+-})-linalool + propan-1-ol{r_brace}: A first stage towards the development of a green process

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Abarrio, Sandra M.; Torcal, Marcos; Haya, M. Luisa; Urieta, Jose S. [Group of Applied Thermodynamics and Surfaces (GATHERS), Aragon Institute for Engineering Research (I3A), Universidad de Zaragoza, Facultad de Ciencias, Zaragoza 50009 (Spain); Mainar, Ana M., E-mail: ammainar@unizar.e [Group of Applied Thermodynamics and Surfaces (GATHERS), Aragon Institute for Engineering Research (I3A), Universidad de Zaragoza, Facultad de Ciencias, Zaragoza 50009 (Spain)

    2011-04-15

    Research highlights: Optimization of supercritical processes needs adequate methods to reproduce the phase behavior. {rho}, u, n{sub D} and related properties of the system linalool+propan-1-ol were studied. Collision Factor (u), Lorentz-Lorenz and Gladstone -Dale (n{sub D}) give the best results. Peng-Robinson, Patel-Teja, SAFT and PC-SAFT were tested as predictive P{rho}T models. PC-SAFT provides the best P{rho}T prediction (20-40 MPa) with an AAD% of 0.83. - Abstract: In this paper, densities, speeds of sound and refractive indexes of binary mixture of {l_brace}({+-})-linalool (1) + propan-1-ol (2){r_brace} at four temperatures (283.15, 298.15, 313.15, and 328.15) K and 0.1 MPa are reported over the whole composition range. These data were used to calculate excess molar volume, speed of sound deviation, excess isentropic compressibility, refractive index deviation, molar refraction, and molar refraction deviation at the four work temperatures. All magnitudes were fitted to the Redlich-Kister equation. Subsequently prediction of speed of sound and refractive index was carried out using several theoretical models or equations. On the other hand, the density of the same mixture was determined in the same temperature range at pressures from 20 MPa to 40 MPa. Four equation of state (Peng-Robinson, Patel-Teja, SAFT, PC-SAFT) were tested as predictive models of the P{rho}T behavior. The best results were obtained by PC-SAFT, with an average absolute deviation of 0.83%.

  8. Thermophysical lesions caused by HZE particles

    International Nuclear Information System (INIS)

    Tobias, C.A.; Malachowski, M.; Nelson, A.; Philpott, D.E.

    1980-01-01

    This paper deals with a type of damage caused by heavy particles that may occur in subcellular structures. These lesions are called thermophysical radiation injury and are similar to damage produced in solids by HZE particles. This chapter summarizes some of the experimental evidence for the presence of these lesions in certain mammalian tissues including the retina, brain, cornea, lens of mice and seeds of corn. Of all tissues examined, only the cornea exhibited a type of lesion which would fulfill the criteria of thermophysical lesions

  9. Thermophysical properties of NbCsub(x)

    International Nuclear Information System (INIS)

    Korolev, L.A.; Taubin, M.L.

    1977-01-01

    The thermal conduction, specific heat, temperature conductivity and electric resistance of the NbCsub(X) compound (C/Nb=0.77; 0.82; 0.94) were measured in the range of temperatures between 20 and 900 deg C. The Lorenz number and the phonon component of the thermal conduction were analyzed and calculated. It was suggested that the phonon component of the thermal conduction is independent of the temperature, while the electron component increases and governs the temperature dependence of thermal conduction of the NbCsub(x) compound above the Debye temperature

  10. Cutinases: properties and industrial applications.

    Science.gov (United States)

    Pio, Tatiana Fontes; Macedo, Gabriela Alves

    2009-01-01

    Cutinases, also known as cutin hydrolases (EC 3.1.1.74) are enzymes first discovered from phytopathogenic fungi that grow on cutin as the sole carbon source. Cutin is a complex biopolymer composed of epoxy and hydroxy fatty acids, and forms the structural component of higher plants cuticle. These enzymes share catalytic properties of lipases and esterases, presenting a unique feature of being active regardless the presence of an oil-water interface, making them interesting as biocatalysts in several industrial processes involving hydrolysis, esterification, and trans-esterification reactions. Cutinases present high stability in organic solvents and ionic liquids, both free and microencapsulated in reverse micelles. These characteristics allow the enzyme application in different areas such as food industry, cosmetics, fine chemicals, pesticide and insecticide degradation, treatment and laundry of fiber textiles, and polymer chemistry. The present chapter describes the characteristics, potential applications, and new perspectives for these enzymes.

  11. Fuel Thermo-physical Characterization Project. Fiscal Year 2014 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Burkes, Douglas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Andrew M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Amanda J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Edwards, Matthew K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); MacFarlan, Paul J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pool, Karl N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Slonecker, Bruce D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smith, Frances N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Steen, Franciska H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-15

    The Office of Material Management and Minimization (M3) Reactor Conversion Fuel Thermo-Physical Characterization Project at Pacific Northwest National Laboratory (PNNL) was tasked with using PNNL facilities and processes to receive irradiated low enriched uranium–molybdenum (LEU-Mo) fuel plate samples and perform analysis in support of the M3 Reactor Conversion Program. This work is in support of the M3 Reactor Conversion Fuel Development Pillar that is managed by Idaho National Laboratory. The primary research scope was to determine the thermo-physical properties as a function of temperature and burnup. Work conducted in Fiscal Year (FY) 2014 complemented measurements performed in FY 2013 on four additional irradiated LEU-Mo fuel plate samples. Specifically, the work in FY 2014 investigated the influence of different processing methods on thermal property behavior, the absence of aluminum alloy cladding on thermal property behavior for additional model validation, and the influence of higher operating surface heat flux / more aggressive irradiation conditions on thermal property behavior. The model developed in FY 2013 and refined in FY 2014 to extract thermal properties of the U-Mo alloy from the measurements conducted on an integral fuel plate sample (i.e., U-Mo alloy with a thin Zr coating and clad in AA6061) continues to perform very well. Measurements conducted in FY 2014 on samples irradiated under similar conditions compare well to measurements performed in FY 2013. In general, there is no gross influence of fabrication method on thermal property behavior, although the difference in LEU-Mo foil microstructure does have a noticeable influence on recrystallization of grains during irradiation. Samples irradiated under more aggressive irradiation conditions, e.g., higher surface heat flux, revealed lower thermal conductivity when compared to samples irradiated at moderate surface heat fluxes, with the exception of one sample. This report documents thermal

  12. Application of the principle of similarity fluid mechanics

    International Nuclear Information System (INIS)

    Hendricks, R.C.; Sengers, J.V.

    1979-01-01

    Possible applications of the principle of similarity to fluid mechanics is described and illustrated. In correlating thermophysical properties of fluids, the similarity principle transcends the traditional corresponding states principle. In fluid mechanics the similarity principle is useful in correlating flow processes that can be modeled adequately with one independent variable (i.e., one-dimensional flows). In this paper we explore the concept of transforming the conservation equations by combining similarity principles for thermophysical properties with those for fluid flow. We illustrate the usefulness of the procedure by applying such a transformation to calculate two phase critical mass flow through a nozzle

  13. Scientific and technical conference Thermophysical experimental and calculating and theoretical studies to justify characteristics and safety of fast reactors. Thermophysics-2012. Book of abstracts

    International Nuclear Information System (INIS)

    Kalyakin, S.G.; Kukharchuk, O.F.; Sorokin, A.P.

    2012-01-01

    The collection includes abstracts of reports of scientific and technical conference Thermophysics-2012 which has taken place on October 24-26, 2012 in Obninsk. In abstracts the following questions are considered: experimental and calculating and theoretical studies of thermal hydraulics of liquid-metal cooled fast reactors to justify their characteristics and safety; physico-chemical processes in the systems with liquid-metal coolants (LMC); physico-chemical characteristics and thermophysical properties of LMC; development of models, computational methods and calculational codes for simulating processes of of hydrodynamics, heat and mass transfer, including impurities mass transfer in the systems with LMC; methods and means for control of composition and condition of LMC in fast reactor circuits on impurities and purification from them; apparatuses, equipment and technological processes at the work with LMC taking into account the ecology, including fast reactors decommissioning; measuring techniques, sensors and devices for experimental studies of heat and mass transfer in the systems with LMC [ru

  14. Thermophysics of fractures on comet 67P/Churyumov-Gerasimenko

    Science.gov (United States)

    Höfner, S.; Vincent, J.-B.; Blum, J.; Davidsson, B. J. R.; Sierks, H.; El-Maarry, M. R.; Deller, J.; Hofmann, M.; Hu, X.; Pajola, M.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.; A'Hearn, M. F.; Auger, A.-T.; Barucci, M. A.; Bertaux, J.-L.; Bertini, I.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Debei, S.; De Cecco, M.; Fornasier, S.; Fulle, M.; Gicquel, A.; Groussin, O.; Gutiérrez, P. J.; Gutiérrez-Marqués, P.; Güttler, C.; Hviid, S. F.; Ip, W.-H.; Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm, J.-R.; Kührt, E.; Küppers, M.; La Forgia, F.; Lazzarin, M.; Lopez-Moreno, J. J.; Marzari, F.; Michalik, H.; Moissl-Fraund, R.; Moreno, F.; Mottola, S.; Naletto, G.; Oklay, N.; Preusker, F.; Scholten, F.; Shi, X.; Thomas, N.; Toth, I.; Tubiana, C.; Zitzmann, S.

    2017-12-01

    Context. The camera OSIRIS on board Rosetta obtained high-resolution images of the nucleus of comet 67P/Churyumov-Gerasimenko (67P). Great parts of the nucleus surface are composed of fractured terrain. Aims: Fracture formation, evolution, and their potential relationship to physical processes that drive activity are not yet fully understood. Observed temperatures and gas production rates can be explained or interpreted with the presence of fractures by applying appropriate modelling methods. Methods: We followed a transient thermophysical model approach that includes radiative, conductive, and water-ice sublimation fluxes by considering a variety of heliocentric distances, illumination conditions, and thermophysical properties for a set of characteristic fracture geometries on the nucleus of 67P. We computed diurnal temperatures, heat fluxes, and outgassing behaviour in order to derive and distinguish the influence of the mentioned parameters on fractured terrain. Results: Our analysis confirms that fractures, as already indicated by former studies about concavities, deviate from flat-terrain topographies with equivalent properties, mostly through the effect of self-heating. Compared to flat terrain, illuminated cometary fractures are generally warmer, with smaller diurnal temperature fluctuations. Maximum sublimation rates reach higher peaks, and dust mantle quenching effects on sublimation rates are weaker. Consequently, the rough structure of the fractured terrain leads to significantly higher inferred surface thermal inertia values than for flat areas with identical physical properties, which might explain the range of measured thermal inertia on 67P. Conclusions: At 3.5 AU heliocentric distance, sublimation heat sinks in fractures converge to maximum values >50 W / m2 and trigger dust activity that can be related mainly to H2O. Fractures are likely to grow through the erosive interplay of alternating sublimation and thermal fatigue.

  15. Thermophysical Analysis of High Modulus Composite Materials for Space Vehicles

    Science.gov (United States)

    Lee, Ho-Sung

    2009-01-01

    High modulus composite materials are used extensively in aerospace vehicles mainly for the purpose of increasing strength and reducing weight. However, thermal properties have become essential design information with the use of composite materials in the thermal design of spacecraft and spacecraft electronics packages. This is because the localized heat from closely packed devices can lead to functional failure of the aerospace system unless the heat is dissipated. In this study, thermal responses of high modulus advanced materials are considered for aerospace thermal design. The advanced composite material is composed of a continuous high modulus pitch based fiber and epoxy resin. In order to compare this advanced composite material with conventional aerospace composite materials, the thermophysical analysis of both materials was performed. The results include thermal conductivity measurements of composite materials and various thermal analytical techniques with DSC, TGA, TMA and DMA.

  16. Preparation and characterization of molten salt based nanothermic fluids with enhanced thermal properties for solar thermal applications

    International Nuclear Information System (INIS)

    Madathil, Pramod Kandoth; Balagi, Nagaraj; Saha, Priyanka; Bharali, Jitalaxmi; Rao, Peddy V.C.; Choudary, Nettem V.; Ramesh, Kanaparthi

    2016-01-01

    Highlights: • Prepared and characterized inorganic ternary molten salt based nanothermic fluids. • MoS 2 and CuO nanoparticles incorporated ternary molten salts have been prepared. • Thermal properties enhanced by the addition of MoS 2 and CuO nanoparticles. • The amount of nanoparticles has been optimized. - Abstract: In the current energy scenario, solar energy is attracting considerable attention as a renewable energy source with ample research and commercial opportunities. The novel and efficient technologies in the solar energy are directed to develop methods for solar energy capture, storage and utilization. High temperature thermal energy storage systems can deal with a wide range of temperatures and therefore they are highly recommended for concentrated solar power (CSP) applications. In the present study, a systematic investigation has been carried out to identify the suitable inorganic nanoparticles and their addition in the molten salt has been optimized. In order to enhance the thermo-physical properties such as thermal conductivity and specific heat capacity of molten salt based HTFs, we report the utilization of MoS 2 and CuO nanoparticles. The enhancement in the above mentioned thermo-physical properties has been demonstrated for optimized compositions and the morphologies of nanoparticle-incorporated molten salts have been studied by scanning electron microscopy (SEM). Nanoparticle addition to molten salts is an efficient method to prepare thermally stable molten salt based heat transfer fluids which can be used in CSP plants. It is also observed that the sedimentation of nanoparticles in molten salt is negligible compared to that in organic heat transfer fluids.

  17. Magnetic materials fundamentals, products, properties, applications

    CERN Document Server

    Hilzinger, Rainer

    2013-01-01

    At a practical level, this compendium reviews the basics of soft and hard magnetic materials, discusses the advantages of the different processing routes for the exploitation of the magnetic properties and hence assists in proper, fail-safe and economic application of magnetic materials. Essential guidelines and formulas for the calculation of the magnetic and electrical properties, temperature and long-term stability of permanent magnets, of inductive components and magnetic shielding are compiled. Selected fields of application and case studies illustrate the large diversity of technical applications. Application engineers will appreciate the comprehensive compilation of the properties and detailed characteristic curves of modern soft and hard magnetic materials. Materials scientists will enjoy the presentation of the different processing routes and their impact on the magnetic properties and students will profit from the survey from the basics of magnetism down to the applications in inductive components, ...

  18. Track membranes, production, properties, applications

    International Nuclear Information System (INIS)

    Oganesjan, Yu.Ts.

    1994-01-01

    The problems of producing track membranes on heavy ion beams of the Flerov Laboratory are considered. The parameters of the running accelerators and equipment for the irradiation of polymer foils are presented. The process of production of track membranes based on different polymeric materials and various applications of the membranes are described. Special attention is given to the principally new applications and devices developed at the Laboratory. This report presents the results obtained by a big group of scientists and engineers working in the field of elaboration, investigation and application of track membranes (author). 21 refs, 20 figs, 1 tab

  19. SHERMAN, a shape-based thermophysical model. I. Model description and validation

    Science.gov (United States)

    Magri, Christopher; Howell, Ellen S.; Vervack, Ronald J.; Nolan, Michael C.; Fernández, Yanga R.; Marshall, Sean E.; Crowell, Jenna L.

    2018-03-01

    SHERMAN, a new thermophysical modeling package designed for analyzing near-infrared spectra of asteroids and other solid bodies, is presented. The model's features, the methods it uses to solve for surface and subsurface temperatures, and the synthetic data it outputs are described. A set of validation tests demonstrates that SHERMAN produces accurate output in a variety of special cases for which correct results can be derived from theory. These cases include a family of solutions to the heat equation for which thermal inertia can have any value and thermophysical properties can vary with depth and with temperature. An appendix describes a new approximation method for estimating surface temperatures within spherical-section craters, more suitable for modeling infrared beaming at short wavelengths than the standard method.

  20. Non-Destructive Infrared Evaluation of Thermo-Physical Parameters in Bamboo Specimens

    Directory of Open Access Journals (Sweden)

    Juan Esteban Ospina-Borras

    2017-12-01

    Full Text Available The estimation of heat conduction properties has considerable importance in the characterization of bamboo with respect to its potential use as an alternative construction material. Even though traditional methods such as hot plates have successfully measured thermal parameters, like thermal diffusivity and conductivity in bamboo samples, it is still necessary to transform the cylindrical bamboo specimen into a piece with special geometry and size. This requirement makes this method impractical in applications where several bamboo specimens need to be measured in their original cylindrical shape. This paper presents the estimation of thermo-physical parameters k and ρ c p in Guadua angustifolia kunth (Guadua a.k. bamboo through nonlinear least square optimization and infrared thermography. A sensitivity analysis was carried out to determine how the temperature on the bamboo surface is affected by changes in the convection coefficient h, thermal conductivity k, and volumetric heat capacity ρ c p . In spite of the nonlinearity and high correlation in the parameters of the inverse heat conduction problem (IHCP, the estimation of such parameters is robust and consistent with those reported in the literature.

  1. Sensitivity of Process Design due to Uncertainties in Property Estimates

    DEFF Research Database (Denmark)

    Hukkerikar, Amol; Jones, Mark Nicholas; Sarup, Bent

    2012-01-01

    of accuracy for different thermo-physical property prediction models; and c) design variables versus properties relationships. The application of the methodology is illustrated through a case study of an extractive distillation process and sensitivity analysis of designs of various unit operations found...... in chemical processes. Among others vapour pressure accuracy for azeotropic mixtures is critical and needs to be measured or estimated with a ±0.25% accuracy to satisfy acceptable safety levels in design....

  2. The properties and applications of nanodiamonds.

    Energy Technology Data Exchange (ETDEWEB)

    Mochalin, Vadym [Drexel University; Shenderova, Olga [International Technology Center, Raleigh, North Carolina; Ho, Dean [Northwestern University, Evanston; Gogotsi, Yury G. [Drexel University

    2011-01-01

    Nanodiamonds have excellent mechanical and optical properties, high surface areas and tunable surface structures. They are also non-toxic, which makes them well suited to biomedical applications. Here we review the synthesis, structure, properties, surface chemistry and phase transformations of individual nanodiamonds and clusters of nanodiamonds. In particular we discuss the rational control of the mechanical, chemical, electronic and optical properties of nanodiamonds through surface doping, interior doping and the introduction of functional groups. These little gems have a wide range of potential applications in tribology, drug delivery, bioimaging and tissue engineering, and also as protein mimics and a filler material for nanocomposites.

  3. The properties and applications of nanodiamonds.

    Science.gov (United States)

    Mochalin, Vadym N; Shenderova, Olga; Ho, Dean; Gogotsi, Yury

    2011-12-18

    Nanodiamonds have excellent mechanical and optical properties, high surface areas and tunable surface structures. They are also non-toxic, which makes them well suited to biomedical applications. Here we review the synthesis, structure, properties, surface chemistry and phase transformations of individual nanodiamonds and clusters of nanodiamonds. In particular we discuss the rational control of the mechanical, chemical, electronic and optical properties of nanodiamonds through surface doping, interior doping and the introduction of functional groups. These little gems have a wide range of potential applications in tribology, drug delivery, bioimaging and tissue engineering, and also as protein mimics and a filler material for nanocomposites.

  4. The Properties and Applications of Nanodiamonds.

    Energy Technology Data Exchange (ETDEWEB)

    Mochalin, V.; Shenderova, O.; Ho, D.; Gogotsi, Y.

    2011-12-18

    Nanodiamonds have excellent mechanical and optical properties, high surface areas and tunable surface structures. They are also non-toxic, which makes them well suited to biomedical applications. Here we review the synthesis, structure, properties, surface chemistry and phase transformations of individual nanodiamonds and clusters of nanodiamonds. In particular we discuss the rational control of the mechanical, chemical, electronic and optical properties of nanodiamonds through surface doping, interior doping and the introduction of functional groups. These little gems have a wide range of potential applications in tribology, drug delivery, bioimaging and tissue engineering, and also as protein mimics and a filler material for nanocomposites.

  5. ThermoData Engine (TDE): Software Implementation of the Dynamic Data Evaluation Concept. 8. Properties of Material Streams and Solvent Design

    DEFF Research Database (Denmark)

    Diky, Vladimir; Chirico, Robert D.; Muzny, Chris D.

    2013-01-01

    ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported in this journal. The present paper describes the first application of this concept to the evaluation of thermophysical properties for material streams involving any number...... extraction from a single-component solvent. Planned future developments are summarized....

  6. [Nanoparticles: properties and application prospects].

    Science.gov (United States)

    Chekman, I S

    2009-01-01

    A new trend of scientific-technical and medical researches has been formed which unites nanoscience, nanotechnology, nanomedicine, nanopharmacology. Nanoparticles are the main product of nanotechnologies. Nanoparticles are organic and inorganic structures, their size being less than one hundred nanometers (nano from Greece nanos--a dwarf; particle is a separate unit which is separated from the whole). Prefix nano means 10(-9) m. Nanosizes are values from 1 to 100 nanometers, micro-sizes--from 100 to 1000 nanometers, and above 1000 nanometers--are macrosizes. By the data of Internet for 1.08.20.2008 there are 18512 papers in the world scientific literature (8663 of them were published during the last 2.5 years), where properties of nanoparticles which are obtained by different nanotechnological methods are described. Actually, quantity of works concerning nanoparticles is much more because not all publications are cited in Internet. The first publication concerning a characteristic of nanoparticles was published in 1978. The survey generalized the data of scientific literature and author's investigations which concern sizes of nanoparticles of biologic molecules and their properties.

  7. [Glucomannan: properties and therapeutic applications].

    Science.gov (United States)

    González Canga, A; Fernández Martínez, N; Sahagún, A M; García Vieitez, J J; Díez Liébana, M J; Calle Pardo, A P; Castro Robles, L J; Sierra Vega, M

    2004-01-01

    Glucomannan is a dietary fiber employed quite frequently in the western countries since two decades now, as its ingestion plays an important role in human health. However, eastern people have used this fiber for more than a thousand years. This dietary fiber is the main polysaccharide obtain from the tubers of the Amorphophallus konjac plant, a member of the family Araceae found in east Asia. The chemical structure of glucomannan consists, mainly, in mannose and glucose in the ratio 8:5 linked by beta (1-->4) glycosidic bonds. This soluble fiber has a extraordinarily high waterholding capacity, forming highly viscous solutions when dissolved in water. It has the highest molecular weight and viscosity of any known dietary fiber. It has been demonstrated that this product is highly effective in the treatment of obesity due to the satiety sensation that it produces; as a remedy for constipation, because it increases the faeces volume; as hypocholesterolemic agent, interfering in the transport of cholesterol and of bile acids and as hypoglycemic and hypoinsulinemic agent, probably, by delaying gastric emptying and slowering glucose delivery to the intestinal mucosa. To the beneficial properties of this fiber, several disadvantages can be added as the production of flatulence, abdominal pain, esophageal obstruction, lower gastrointestinal obstruction or even the possible modification of the bioavailability of other drugs. This paper reviews the main characteristics of glucomannan, as well as its properties, physiologic effects and therapeutic uses.

  8. Thermophysical characterization of N-methyl-2-hydroxyethylammonium carboxilate ionic liquids

    OpenAIRE

    Talavera-Prieto, Nieves M. C.; Ferreira, Abel G. M.; Simões, Pedro N.; Carvalho, Pedro J.; Mattedi, Silvana; Coutinho, João A. P.

    2014-01-01

    The thermophysical properties including density, heat capacity, thermal stability and phase behaviour of protic ionic liquids based on the N-methyl-2-hydroxyethylammonium cation, [C2OHC1NH2]+, with the carboxylate anions (propionate, [C2COO]−, butyrate, [C3COO]−, and pentanoate, [C4COO]−) are reported and used to evaluate structure-property relationships. The density was measured over the temperature and pressure ranges, T = (298.15 to 358.15) K and p = (0.1 to 25) MPa, respectively, with an ...

  9. High pressure thermophysical behaviour of reference and new lubricants. Mineral, synthetic and vegetable oils and ionic liquids

    OpenAIRE

    Regueira Muñiz, Teresa

    2013-01-01

    This PhD Thesis is devoted to the study of several thermophysical properties, over broad ranges of temperature and pressure, of mineral and semisynthetic reference lubricants, vegetable oils and developed biodegradable lubricants, as well as ionic liquids (ILs) for their use as hydraulic fluids, gear and two stroke lubricants. The first property studied was the density from 278.15 K to 398.15 K up to 120 MPa. Density was measured by means of two different vibrating tube densime...

  10. Thermophysical modeling of asteroids from WISE thermal infrared data - Significance of the shape model and the pole orientation uncertainties

    Science.gov (United States)

    Hanuš, J.; Delbo', M.; Ďurech, J.; Alí-Lagoa, V.

    2015-08-01

    In the analysis of thermal infrared data of asteroids by means of thermophysical models (TPMs) it is a common practice to neglect the uncertainty of the shape model and the rotational state, which are taken as an input for the model. Here, we present a novel method of investigating the importance of the shape model and the pole orientation uncertainties in the thermophysical modeling - the varied shape TPM (VS-TPM). Our method uses optical photometric data to generate various shape models that map the uncertainty in the shape and the rotational state. The TPM procedure is then run for all these shape models. We apply the implementation of the classical TPM as well as our VS-TPM to the convex shape models of several asteroids together with their thermal infrared data acquired by the NASA's Wide-field Infrared Survey Explorer (WISE) and compare the results. These show that the uncertainties of the shape model and the pole orientation can be very important (e.g., for the determination of the thermal inertia) and should be considered in the thermophysical analyses. We present thermophysical properties for six asteroids - (624) Hektor, (771) Libera, (1036) Ganymed, (1472) Muonio, (1627) Ivar, and (2606) Odessa.

  11. Thorium dioxide: properties and nuclear applications

    International Nuclear Information System (INIS)

    Belle, J.; Berman, R.M.

    1984-01-01

    This is the sixth book on reactor materials published under sponsorship of the Naval Reactors Office of the United States Department of Energy, formerly the United States Atomic Energy Commission. This book presents a comprehensive compilation of the most significant properties of thorium dioxide, much like the book Uranium Dioxide: Properties and Nuclear Applications presented information on the fuel material used in the Shippingport Pressurized Water Reactor core

  12. Thorium dioxide: properties and nuclear applications

    Energy Technology Data Exchange (ETDEWEB)

    Belle, J.; Berman, R.M. (eds.)

    1984-01-01

    This is the sixth book on reactor materials published under sponsorship of the Naval Reactors Office of the United States Department of Energy, formerly the United States Atomic Energy Commission. This book presents a comprehensive compilation of the most significant properties of thorium dioxide, much like the book Uranium Dioxide: Properties and Nuclear Applications presented information on the fuel material used in the Shippingport Pressurized Water Reactor core.

  13. Properties and applications of chemically functionalized graphene

    International Nuclear Information System (INIS)

    Craciun, M F; Khrapach, I; Barnes, M D; Russo, S

    2013-01-01

    The vast and yet largely unexplored family of graphene materials has great potential for future electronic devices with novel functionalities. The ability to engineer the electrical and optical properties in graphene by chemically functionalizing it with a molecule or adatom is widening considerably the potential applications targeted by graphene. Indeed, functionalized graphene has been found to be the best known transparent conductor or a wide gap semiconductor. At the same time, understanding the mechanisms driving the functionalization of graphene with hydrogen is proving to be of fundamental interest for energy storage devices. Here we discuss recent advances on the properties and applications of chemically functionalized graphene. (topical review)

  14. Anisotropic nanomaterials preparation, properties, and applications

    CERN Document Server

    Li, Quan

    2015-01-01

    In this book anisotropic one-dimensional and two-dimensional nanoscale building blocks and their assembly into fascinating and qualitatively new functional structures embracing both hard and soft components are explained. Contributions from leading experts regarding important aspects like synthesis, assembly, properties and applications of the above materials are compiled into a reference book. The anisotropy, i.e. the direction-dependent physical properties, of materials is fascinating and elegant and has sparked the quest for anisotropic materials with useful properties. With such a curiosi

  15. Surface active monomers synthesis, properties, and application

    CERN Document Server

    Borzenkov, Mykola

    2014-01-01

    This brief includes information on the background?of and development of synthesis of various types of surface active monomers. The authors explain the importance of utilization of surface active monomers for creation of surface active polymers? and the various biomedical applications of such compounds . This brief introduces techniques for the synthesis of novel types of surface active monomers, their colloidal and polymerizable properties and application for needs of medicine and biology.

  16. Thin metal nanostructures: synthesis, properties and applications

    OpenAIRE

    Fan, Zhanxi; Huang, Xiao; Tan, Chaoliang; Zhang, Hua

    2014-01-01

    Two-dimensional nanomaterials, especially graphene and single- or few-layer transition metal dichalcogenide nanosheets, have attracted great research interest in recent years due to their distinctive physical, chemical and electronic properties as well as their great potentials for a broad range of applications. Recently, great efforts have also been devoted to the controlled synthesis of thin nanostructures of metals, one of the most studied traditional materials, for various applications. I...

  17. Thermophysical Modeling of Recent Lava Flows in Daedalia Planum, Mars

    Science.gov (United States)

    Ramsey, M. S.; Simurda, C.; Crown, D. A.

    2017-12-01

    Mantling by eolian-derived material (i.e., dust and sand) can hinder compositional analysis of the Martian surface by obscuring the spectral signature of underlying coarser grained materials and bedrock. However, checkboard style mixing of larger lava outcrops plus fine-grained material in low-lying regions can also result in a spectrum similar to that of a continuous, optically-thin layer of fine material. Multiple datasets with either high spatial or spectral resolution were used to identify these mixing relationships on the flow surfaces in Daedalia Planum in hope of discerning the spectral signature of the lava. Daedalia Planum contains a flow apron originating from the SW flank of Arsia Mons, the southernmost Tharsis shield volcano, and was selected for its coverage by multiple datasets and extensive basaltic lava flow fields. CTX and HiRISE images were used to visually identify flow boundaries, superposition relationships, and surface morphology. THEMIS derived thermal inertia (TI) was compared with THEMIS infrared (IR) day and night brightness temperature (PBT) to determine the thermophysical response of individual flows. Statistical analysis (including ANOVA) of regions of interest (ROIs) in the TI and PBT data was performed to also assess the variability across the entire flow field. Four categories were defined based on these results. Finally, these THEMIS-defined categories, TI, and surface morphology were compared to identify possible unmantled outcrops. Analyses of thermophysical properties and flow morphology reveal that individual flows respond differently to diurnal heating, suggesting the presence of different roughness distributions or mixing relationships between the mantling material and lava outcrops. Statistical analysis reveals that flows with rugged surfaces are most likely to have a checkboard mixing distribution. The identification of the flows with minimally-mantled lava outcrops will next be used with TI modeling to determine its

  18. Thermophysical characterization of 1-ethylpyridinium triflate and comparison with similar ionic liquids

    International Nuclear Information System (INIS)

    García-Andreu, María; Castro, Miguel; Gascón, Ignacio; Lafuente, Carlos

    2016-01-01

    Highlights: • A thermophysical characterization of 1-ethylpyridinium triflate is presented. • The properties have been correlated with temperature. • The density at T = 303.15 K at several pressures has been also measured. • This study includes the thermal properties around the normal melting point. • A comparison with similar ionic liquids has been established. - Abstract: We present here a comprehensive thermophysical study of the piridynium-based ionic liquid: 1-ethylpyridinium triflate. Density, speed of sound, refractive index, surface tension, isobaric molar heat capacity, kinematic viscosity and electrical conductivity have been determined in the temperature range (293.15–338.15 K) and at pressure of 0.1 MPa, density was also measured in the pressure range (0.1–40 MPa) at T = 303.15 K. From these values, some derived properties have been calculated. In addition the thermal behaviour around the melting point has been registered. All these properties have been discussed and compared with those of two similar ionic liquids, 1-ethylpyridinium bis(trifluoromethylsulfonyl)imide and 1-butylpyridinium triflate.

  19. Spin-crossover materials properties and applications

    CERN Document Server

    Halcrow, Malcolm A

    2013-01-01

    The phenomenon of spin-crossover has a large impact on the physical properties of a solid material, including its colour, magnetic moment, and electrical resistance. Some materials also show a structural phase change during the transition. Several practical applications of spin-crossover materials have been demonstrated including display and memory devices, electrical and electroluminescent devices, and MRI contrast agents. Switchable liquid crystals, nanoparticles, and thin films of spin-crossover materials have also been achieved. Spin-Crossover Materials: Properties and Applicat

  20. Bioactive glasses materials, properties and applications

    CERN Document Server

    Ylänen, Heimo

    2011-01-01

    Due to their biocompatibility and bioactivity, bioactive glasses are used as highly effective implant materials throughout the human body to replace or repair damaged tissue. As a result, they have been in continuous use since shortly after their invention in the late 1960s and are the subject of extensive research worldwide.Bioactive glasses provides readers with a detailed review of the current status of this unique material, its properties, technologies and applications. Chapters in part one deal with the materials and mechanical properties of bioactive glass, examining topics such

  1. Photorefractive optics materials, properties, and applications

    CERN Document Server

    Yu, Francis T S

    1999-01-01

    The advances of photorefractive optics have demonstrated many useful and practical applications, which include the development of photorefractive optic devices for computer communication needs. To name a couple significant applications: the large capacity optical memory, which can greatly improve the accessible high-speed CD-ROM and the dynamic photorefractive gratings, which can be used for all-optic switches for high-speed fiber optic networks. This book is an important reference both for technical and non-technical staffs who are interested in this field. * Covers the recent development in materials, phenomena, and applications * Includes growth, characterization, dynamic gratings, and liquid crystal PR effect * Includes applications to photonic devices such as large capacity optical memory, 3-D interconnections, and dynamic holograms * Provides the recent overall picture of current trends in photorefractive optics * Includes optical and electronic properties of the materials as applied to dynamic photoref...

  2. Gluconic Acid: Properties, Applications and Microbial Production

    Directory of Open Access Journals (Sweden)

    Sumitra Ramachandran

    2006-01-01

    Full Text Available Gluconic acid is a mild organic acid derived from glucose by a simple oxidation reaction. The reaction is facilitated by the enzyme glucose oxidase (fungi and glucose dehydrogenase (bacteria such as Gluconobacter. Microbial production of gluconic acid is the preferred method and it dates back to several decades. The most studied and widely used fermentation process involves the fungus Aspergillus niger. Gluconic acid and its derivatives, the principal being sodium gluconate, have wide applications in food and pharmaceutical industry. This article gives a review of microbial gluconic acid production, its properties and applications.

  3. Graphene optoelectronics synthesis, characterization, properties, and applications

    CERN Document Server

    bin M Yusoff, Abdul Rashid

    2014-01-01

    This first book on emerging applications for this innovative material gives an up-to-date account of the many opportunities graphene offers high-end optoelectronics.The text focuses on potential as well as already realized applications, discussing metallic and passive components, such as transparent conductors and smart windows, as well as high-frequency devices, spintronics, photonics, and terahertz devices. Also included are sections on the fundamental properties, synthesis, and characterization of graphene. With its unique coverage, this book will be welcomed by materials scientists, solid-

  4. Comparing the thermo-physical characteristics of lard and selected plant fats

    Directory of Open Access Journals (Sweden)

    Yanty, N. A. M.

    2012-09-01

    Full Text Available A comparison of the thermo-physical properties of lard and plant fats may help to formulate alternative fat substitutes for halal food applications. In this study, plant-based fats, namely avocado butter (Persea americana, cocoa butter (Theobroma cacao L., palm oil (Elaeis guinensis and mee fat (Madhuca longifolia are compared to lard with respect to the basic physico-chemical parameters, fatty acid and triacylglycerol (TAG compositions, and melting and solidification behaviors. Although plant fats are completely different from lard with respect to fatty acid and TAG compositions, they share some common thermal features with lard. Based on thermal analysis, lard and plant fats, except cocoa butter, are found to have thermal transitions in both low (< 0 °C and high (> 0 °C melting regions of their cooling and melting curves. According to pulse NMR data, mee fat and lard are found to display closely similar solidification profiles in the temperature range of 0-25 °C, while palm oil and lard are found to have similar solidification profiles in the temperature range between 25-40 °C. Hence, the thermo-physical property comparison between plant fats and lard may be useful to formulate a fat blend which simulates the thermal properties of lard.

    La comparación de las propiedades térmica y mecánicas de la manteca de cerdo y la de determinadas grasas de plantas, podría ayudar a formular sustitutos alternativos de las grasas para aplicaciones alimentarias. En este estudio, basado en materias grasas vegetales como, aguacate (Persea americana, manteca de cacao (Theobroma cacao L., palma aceitera (Elaeis guinensis y grasa de mee (Madhuca longifolia se comparan con la manteca de cerdo con respecto a parámetros físico-químicos, composiciones en ácidos grasos y triglicéridos (TAG, y comportamientos de los parámetros de fusión y de solidificación. Aunque las grasas de plantas

  5. Polyfuran Conducting Polymers: Synthesis, Properties, and Applications.

    OpenAIRE

    González-Tejera, M.J.; Sánchez de la Blanca, Emilia; Carrillo Ramiro, Isabel

    2008-01-01

    In this review, polyfuran (PFu) synthesis methods and the nucleation mechanism; the electrochemical, structural, morphological, and magnetic properties of PFu; thermal behavior; theoretical calculations on PFu, as well as its applications reported to date, have been compiled. Not only PFu homopolymers have been reviewed, but also PFu co-polymers, PFu bipolymers, and PFu composites. The results are listed, discussed, and compared. It is hoped that this assembly of all the relevant data might e...

  6. Thermophysical characteristics of the large main-belt asteroid (349) Dembowska

    Science.gov (United States)

    Yu, Liang Liang; Yang, Bin; Ji, Jianghui; Ip, Wing-Huen

    2017-12-01

    (349) Dembowska is a large, bright main-belt asteroid that has a fast rotation and an oblique spin axis. It might have experienced partial melting and differentiation. We constrain Dembowska's thermophysical properties, such as thermal inertia, roughness fraction, geometric albedo and effective diameter within 3σ uncertainty of Γ =20^{+12}_{-7} Jm-2 s-0.5 K-1, f_r=0.25^{+0.60}_{-0.25}, p_v=0.309^{+0.026}_{-0.038} and D_eff=155.8^{+7.5}_{-6.2} km, by utilizing the advanced thermophysical model to analyse four sets of thermal infrared data obtained by the Infrared Astronomy Satellite (IRAS), AKARI, the Wide-field Infrared Survey Explorer (WISE) and the Subaru/Cooled Mid-Infrared Camera and Spectrometer (COMICS) at different epochs. In addition, by modelling the thermal light curve observed by WISE, we obtain the rotational phases of each data set. These rotationally resolved data do not reveal significant variations of thermal inertia and roughness across the surface, indicating that the surface of Dembowska should be covered by a dusty regolith layer with few rocks or boulders. Besides, the low thermal inertia of Dembowska shows no significant difference with other asteroids larger than 100 km, which indicates that the dynamical lives of these large asteroids are long enough to make their surfaces have sufficiently low thermal inertia. Furthermore, based on the derived surface thermophysical properties, as well as the known orbital and rotational parameters, we can simulate Dembowska's surface and subsurface temperatures throughout its orbital period. The surface temperature varies from ∼40 to ∼220 K, showing significant seasonal variation, whereas the subsurface temperature achieves equilibrium temperature about 120-160 K below a depth of 30-50 cm.

  7. Diamond nanowires: fabrication, structure, properties, and applications.

    Science.gov (United States)

    Yu, Yuan; Wu, Liangzhuan; Zhi, Jinfang

    2014-12-22

    C(sp(3) )C-bonded diamond nanowires are wide band gap semiconductors that exhibit a combination of superior properties such as negative electron affinity, chemical inertness, high Young's modulus, the highest hardness, and room-temperature thermal conductivity. The creation of 1D diamond nanowires with their giant surface-to-volume ratio enhancements makes it possible to control and enhance the fundamental properties of diamond. Although theoretical comparisons with carbon nanotubes have shown that diamond nanowires are energetically and mechanically viable structures, reproducibly synthesizing the crystalline diamond nanowires has remained challenging. We present a comprehensive, up-to-date review of diamond nanowires, including a discussion of their synthesis along with their structures, properties, and applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Sintered soft magnetic materials. Properties and applications

    Science.gov (United States)

    Bas, J. A.; Calero, J. A.; Dougan, M. J.

    2003-01-01

    A comparison is presented of the characteristics and production requirements of a variety of materials used to produce sintered soft magnetic parts. These include pure iron, phosphorous-iron, silicon-iron, nickel-iron, and cobalt-iron, together with new coated materials based on encapsulated iron powders. In these bonded materials an organic and/or inorganic insulator is used to coat the metallic powder particles giving a magnetic composite. The suitability of the different materials for use in both direct and alternating current applications is reviewed, and examples are provided of their application in both the automotive and other sectors. The results of a comparative study of motors using stators and rotors based on both conventional laminated materials and the insulated iron powders are presented, in which the new materials show advantages of reduced hysteresis losses at high frequencies, and isotropy of magnetic properties. Nevertheless, the applications of these materials in electrical motors requires the modification of existing designs.

  9. Thermophysical and rheological properties of dulce de leche with and without coconut flakes as a function of temperature Propriedades termofísicas e reológicas de doces de leite puro e adicionado de flocos de coco em função da temperatura

    Directory of Open Access Journals (Sweden)

    Vanessa Camarinha Barbosa

    2013-03-01

    Full Text Available Dulce de leche (DL, a dairy dessert highly appreciated in Brazil, is a concentrated product containing about 70% m/m of total solids. Thermophysical and rheological properties of two industrial Brazilian Dulce de leche formulations (classic Dulce de leche and Dulce de leche added with coconut flakes 1.5% m/m were determined at temperatures comprised between 28.4 and 76.4 °C. In general, no significant differences (p Doce de leite é uma sobremesa láctea concentrada (cerca de 70% de sólidos muito apreciada no Brasil. Propriedades termofísicas e reológicas de duas formulações de doce de leite brasileiro (puro e adicionado de coco ralado a 1,5% em massa foram determinadas a temperaturas compreendidas entre 28,4 e 76,4 °C. No geral, a presença de flocos de coco não acarretou diferenças significativas (p < 0,05 nestas propriedades das duas formulações. A capacidade calorífica variou entre (2633,2 e 3101,8 J/kg.°C; a condutividade térmica entre (0,383 e 0,452 W/m°C; a massa específica entre (1350,7 e 1310,7 kg/m³; e enfim, a difusividade térmica entre (1,082 × 10-7 e 1,130 × 10-7 m²/s. O modelo de Bingham descreveu adequadamente o comportamento não Newtoniano dos dois produtos, com tensão crítica de escoamento variando entre (27,3 e 17,6 Pa e a viscosidade plástica de (19,9 a 5,9 Pa.s.

  10. Geopolymers: Structures, Processing, Properties and Industrial applications

    Energy Technology Data Exchange (ETDEWEB)

    Provis, J.L.; van Deventer, J.S.J. (eds.) [University of Melbourne, Vic. (Australia)

    2009-06-15

    A geopolymer is a solid aluminosilicate material usually formed by alkali hydroxide or alkali silicate activation of a solid precursor such as coal fly ash, calcined clay and/or metallurgical slag. Part one discusses the synthesis and characterisation of geopolymers with chapters on topics such as fly ash chemistry and inorganic polymer cements, geopolymer precursor design, nanostructure/microstructure of metakaolin and fly ash geopolymers, and geopolymer synthesis kinetics. Part two reviews the manufacture and properties of geopolymers including accelerated ageing of geopolymers, chemical durability, engineering properties of geopolymer concrete, producing fire and heat-resistant geopolymers, utilisation of mining wastes and thermal properties of geopolymers. Part three covers applications of geopolymers with coverage of topics such as commercialisation of geopolymers for construction, as well as applications in waste management. Chapters of particular relevance are: Fly ash glass chemistry and inorganic polymer cements by L.M. Keyte, University of Melbourne, Australia; Nanostructure/microstructure of metakaolin geopolymers by A. Fernanez-Jimenez and A. Palomo, Eduardo Torroja Institute, Spain; Utilisation of mining wastes to produce geopolymer binders by F. Pacheco-Torgal and S. Jalali, University of Minho and J.P. Castro-Gomes, University of Beira Interior, Portugal.

  11. Silkworm Sericin: Properties and Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Regina Inês Kunz

    2016-01-01

    Full Text Available Silk sericin is a natural polymer produced by silkworm, Bombyx mori, which surrounds and keeps together two fibroin filaments in silk thread used in the cocoon. The recovery and reuse of sericin usually discarded by the textile industry not only minimizes environmental issues but also has a high scientific and commercial value. The physicochemical properties of the molecule are responsible for numerous applications in biomedicine and are influenced by the extraction method and silkworm lineage, which can lead to variations in molecular weight and amino acid concentration of sericin. The presence of highly hydrophobic amino acids and its antioxidant potential make it possible for sericin to be applied in the food and cosmetic industry. The moisturizing power allows indications as a therapeutic agent for wound healing, stimulating cell proliferation, protection against ultraviolet radiation, and formulating creams and shampoos. The antioxidant activity associated with low digestibility of sericin that expands the application in the medical field, such as antitumour, antimicrobial and anti-inflammatory agent, anticoagulant, acts in colon health, improving constipation and protects the body from obesity through improved plasma lipid profile. In addition, the properties of sericin allow its application as a culture medium and cryopreservation, in tissue engineering and for drug delivery, demonstrating its effective use, as an important biomaterial.

  12. Silkworm Sericin: Properties and Biomedical Applications.

    Science.gov (United States)

    Kunz, Regina Inês; Brancalhão, Rose Meire Costa; Ribeiro, Lucinéia de Fátima Chasko; Natali, Maria Raquel Marçal

    2016-01-01

    Silk sericin is a natural polymer produced by silkworm, Bombyx mori , which surrounds and keeps together two fibroin filaments in silk thread used in the cocoon. The recovery and reuse of sericin usually discarded by the textile industry not only minimizes environmental issues but also has a high scientific and commercial value. The physicochemical properties of the molecule are responsible for numerous applications in biomedicine and are influenced by the extraction method and silkworm lineage, which can lead to variations in molecular weight and amino acid concentration of sericin. The presence of highly hydrophobic amino acids and its antioxidant potential make it possible for sericin to be applied in the food and cosmetic industry. The moisturizing power allows indications as a therapeutic agent for wound healing, stimulating cell proliferation, protection against ultraviolet radiation, and formulating creams and shampoos. The antioxidant activity associated with low digestibility of sericin that expands the application in the medical field, such as antitumour, antimicrobial and anti-inflammatory agent, anticoagulant, acts in colon health, improving constipation and protects the body from obesity through improved plasma lipid profile. In addition, the properties of sericin allow its application as a culture medium and cryopreservation, in tissue engineering and for drug delivery, demonstrating its effective use, as an important biomaterial.

  13. Properties and applications of perovskite proton conductors

    Directory of Open Access Journals (Sweden)

    Eduardo Caetano Camilo de Souza

    2010-09-01

    Full Text Available A brief overview is given of the main types and principles of solid-state proton conductors with perovskite structure. Their properties are summarized in terms of the defect chemistry, proton transport and chemical stability. A good understanding of these subjects allows the manufacturing of compounds with the desired electrical properties, for application in renewable and sustainable energy devices. A few trends and highlights of the scientific advances are given for some classes of protonic conductors. Recent results and future prospect about these compounds are also evaluated. The high proton conductivity of barium cerate and zirconate based electrolytes lately reported in the literature has taken these compounds to a highlight position among the most studied conductor ceramic materials.

  14. Beryllium - a light metal with special properties and its treatment

    International Nuclear Information System (INIS)

    Aldinger, F.

    1977-01-01

    The author presents a comprehensive report on beryllium which has some unusual properties for a light metal. The points discussed are: Production and processing, mechanical properties (Young's modulus, tensile strength), electrical resistivity, thermophysical properties, applications, toxicology. Due to its nuclear physical properties (low neutron absorption, high moderating factor) it is also suitable as moderator and reflector material for nuclear reactors. However, it has not been possible yet to overcome tthe disadvantage of beryllium swelling under neutron irradiation at temperatures over 600 0 C. (GSC) [de

  15. Structural-functional concept of thermophysical condition of the soils of Altai Region

    Directory of Open Access Journals (Sweden)

    Sergey Makarychev

    2016-10-01

    Full Text Available The goal of this study was to reveal the quantitative interrelations between the thermophysical indices (thermal conductivity and thermal diffusivity and physical soil properties such as; moisture content, density and detachability. According to the research targets, the soil samples including different genesis and soil particle size distribution were taken in different soil and climatic zones of the Altai Region. These were the sod-podzolic sandy loam soils of the dry steppes, chernozems and chestnut soils of light and medium loamy particle size distribution of temperately arid zone, and the heavy loamy gray forest soils and clayey chernozems of the Altai foothills and low mountains. The samples of undisturbed structures in different soil horizons were studied. To measure the thermophysical properties in laboratory setting, a pulse method of a two-dimensional heat source was used. The method takes into account the patterns of temperature field equalization in an unbounded medium after the heat source termination. A feature of this process is the occurrence of peak temperature at the investigated point of the medium at a given instant. The knowledge of this temperature and time enables to determine the soil thermal capacity, thermal conductivity and thermal diffusivity.

  16. Thermophysical and spectroscopic studies of room temperature ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate in Tritons

    International Nuclear Information System (INIS)

    Chaudhary, Ganga Ram; Bansal, Shafila; Mehta, S.K.; Ahluwalia, A.S.

    2012-01-01

    Highlights: ► Thermophysical studies of new formulations of [BMIM][PF 6 ]+TX(45,100) have been made. ► Strong intermolecular interactions between [BMIM][PF 6 ] and TX (45, 100) is observed. ► Magnitude of interactions increases with the addition of oxyethylene groups in TX. ► With rise in temperature, intermolecular interactions increases. ► Spectroscopic studies show that interactions are via aromatic rings of RTIL and TX. - Abstract: The thermophysical properties viz. density ρ, speed of sound u, and specific conductivity κ of pure room temperature ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) and its binary formulations with Triton X-45 and Triton X-100 have been studied over the entire composition range at different temperatures (293.15 to 323.15) K. Excess molar volume V E , deviation in isentropic compressibility ΔK S , partial molar excess volume V i E , deviation in partial molar isentropic compressibility ΔK S,i , deviation in specific conductivity Δκ have also been estimated and analysed. Spectroscopic properties (IR, 1 H and 13 C NMR) of these mixtures have been investigated in order to understand the structural and interactional behaviour of formulations studied. The magnitude of interactions between the two components increases with addition of number of oxyethylene groups in Tritons and with rise in temperature. Spectroscopic measurements indicate that interactions are mainly taking place through the five member ring of room temperature ionic liquid and six member ring of Tritons.

  17. Engineered Proteins: Redox Properties and Their Applications

    Science.gov (United States)

    Prabhulkar, Shradha; Tian, Hui; Wang, Xiaotang; Zhu, Jun-Jie

    2012-01-01

    Abstract Oxidoreductases and metalloproteins, representing more than one third of all known proteins, serve as significant catalysts for numerous biological processes that involve electron transfers such as photosynthesis, respiration, metabolism, and molecular signaling. The functional properties of the oxidoreductases/metalloproteins are determined by the nature of their redox centers. Protein engineering is a powerful approach that is used to incorporate biological and abiological redox cofactors as well as novel enzymes and redox proteins with predictable structures and desirable functions for important biological and chemical applications. The methods of protein engineering, mainly rational design, directed evolution, protein surface modifications, and domain shuffling, have allowed the creation and study of a number of redox proteins. This review presents a selection of engineered redox proteins achieved through these methods, resulting in a manipulation in redox potentials, an increase in electron-transfer efficiency, and an expansion of native proteins by de novo design. Such engineered/modified redox proteins with desired properties have led to a broad spectrum of practical applications, ranging from biosensors, biofuel cells, to pharmaceuticals and hybrid catalysis. Glucose biosensors are one of the most successful products in enzyme electrochemistry, with reconstituted glucose oxidase achieving effective electrical communication with the sensor electrode; direct electron-transfer-type biofuel cells are developed to avoid thermodynamic loss and mediator leakage; and fusion proteins of P450s and redox partners make the biocatalytic generation of drug metabolites possible. In summary, this review includes the properties and applications of the engineered redox proteins as well as their significance and great potential in the exploration of bioelectrochemical sensing devices. Antioxid. Redox Signal. 17, 1796–1822. PMID:22435347

  18. Graphene Nanoelectronics Metrology, Synthesis, Properties and Applications

    CERN Document Server

    2012-01-01

    Graphene is a perfectly two-dimensional single-atom thin membrane with zero bandgap. It has attracted huge attention due to its linear dispersion around the Dirac point, excellent transport properties, novel magnetic characteristics, and low spin-orbit coupling. Graphene and its nanostructures may have potential applications in spintronics, photonics, plasmonics and electronics. This book brings together a team of experts to provide an overview of the most advanced topics in theory, experiments, spectroscopy and applications of graphene and its nanostructures. It covers the state-of-the-art in tutorial-like and review-like manner to make the book useful not only to experts, but also newcomers and graduate students.

  19. Exponentiated Lomax Geometric Distribution: Properties and Applications

    Directory of Open Access Journals (Sweden)

    Amal Soliman Hassan

    2017-09-01

    Full Text Available In this paper, a new four-parameter lifetime distribution, called the exponentiated Lomax geometric (ELG is introduced. The new lifetime distribution contains the Lomax geometric and exponentiated Pareto geometric as new sub-models. Explicit algebraic formulas of probability density function, survival and hazard functions are derived. Various structural properties of the new model are derived including; quantile function, Re'nyi entropy, moments, probability weighted moments, order statistic, Lorenz and Bonferroni curves. The estimation of the model parameters is performed by maximum likelihood method and inference for a large sample is discussed. The flexibility and potentiality of the new model in comparison with some other distributions are shown via an application to a real data set. We hope that the new model will be an adequate model for applications in various studies.

  20. Cellulose nanocrystal properties and their applications

    Directory of Open Access Journals (Sweden)

    mahdi jonoobi

    2015-05-01

    Full Text Available The main purpose of this work is to provide an overview of recent research in the area of cellulose nonmaterials production from different sources. Due to their abundance, their renewability, high strength and stiffness, being eco-friendly, and low weight; numerous studies have been reported on the isolation of cellulose nanomaterials from different cellulosic sources and their use in high performance applications. This work covers an introduction into the nano cellulose definition as well as used methods for isolation of nanomaterials (nanocrystals from various sources. The rod-like cellulose nanocrystals (CNC can be isolated from sources like wood, plant fibers, agriculture and industrial bio residues, tunicates, and bacterial cellulose using acid hydrolysis process. Following this, the paper focused on characterization methods, materials properties and structure. The current review is a comprehensive literature regarding the nano cellulose isolation and demonstrates the potential of cellulose nanomaterials to be used in a wide range of high-tech applications.

  1. Thermophysical characterization of the powder resulting from the ...

    African Journals Online (AJOL)

    This paper presents the results of thermophysical characterization of the powder resulting from the solar drying of Moringa oleifera leaves. The desorption isotherms of the powder, are determined by the gravimetric static method. The models of B.E.T, Smith, Henderson, Iglesias and GAB are used for the smoothing of the ...

  2. Experience of web-complex development of NPP thermophysical optimization

    International Nuclear Information System (INIS)

    Nikolaev, M.A.

    2014-01-01

    Current state of developing computation web complex (CWC) of thermophysical optimization of nuclear power plants is described. Main databases of CWC is realized on the MySQL platform. CWC information architecture, its functionality, optimization algorithms and CWC user interface are under consideration [ru

  3. Microbial lipases: Production, properties and biotechnological applications

    Directory of Open Access Journals (Sweden)

    Josana Maria Messias

    2011-09-01

    Full Text Available Lipases belong to the group of hydrolases that catalyze the hydrolysis of triacylglycerol lipids to free fatty acids and glycerol. They have significant potential biotechnological applications in catalyzing organic synthesis reactions in non-aqueous solvents using simplified procedures resulting in conversions of high yields. Lipase production has conventionally been performed by submerged fermentation; however, solid-state fermentation processes have been prominent when residues are used as substrates because they serve as low-cost nutrient sources. Microbial lipases can be used as additives in foods to modify and enhance organoleptic properties, as well as in detergents to hydrolyse fats in the treatment of oily effluents, and also have value for pharmaceutical, cosmetic, agrochemical, and oil chemical industries. More recently, they are used in transesterification reactions to convert plant seed oils into biodiesel. The objective of this work was to review the published literature on the production, properties and applications of microbial lipases, and its biotechnological role in producing biodiesel.

  4. Material properties of ceramics for dental applications

    Science.gov (United States)

    Quinn, Janet Bernice

    2000-12-01

    Ceramic tooth-replacement materials have been greatly improved since their introduction near the end of the eighteenth century, but still have problems concerning clinical performance and aesthetics. Material property testing has advanced as well as the ability to form new dental ceramics. The purpose of this study was to test some of the new materials according to recently developed standards, and to utilize the results to better understand, predict and determine how to improve dental material performance and machinability. Aspects of this study include unique applications of testing methodology and the development of a new edge chipping test. A new brittleness parameter, B, is introduced. Unlike previously suggested brittleness parameters, B has theoretical significance as a volume energy to surface energy ratio. The ascertained properties were used to evaluate the dental ceramics. Toughness-related parameters were important in the clinical results, and correlations with microstructural characteristics indicate potential improvements as well as limitations. A good fit to a model predicting toughness increases with grain size, for example, suggests processing-induced thermal mismatch stresses as a toughening mechanism in glass-ceramics. Stresses that are too high, however, can result in local microcracking and a decrease in toughness. Machinability is of particular importance in fabricating dental components, which have complicated shapes and tight tolerances. As there is no currently accepted quantitative definition of machinability, a subjective analysis involving professional machinists and a regression analysis was used. Material properties and a theoretical model for material removal rates, based on lateral crack formation, were compared with the subjective machinability rankings. Although there were differences among the machinists' criteria, hardness was found to be the single most effective property in predicting machinability. High temperature properties

  5. Achievements in the field of thermophysics of pniktides and chalcogenides of transition elements

    International Nuclear Information System (INIS)

    Westrum, E.F.

    1979-01-01

    Thermophysical aspects of thermodynamics of chalcogenides of transition metals are analyzed briefly with the aim of development of concepts on connection of these compounds entropy with their structure, expressed by Grenvold and Westrum in 1962. In a more detail way discussed are the achievement in the field of low-temperature thermophysics of pniktides of transition metals permitting to consider the similarity and the differences in properties of the two compound classes mentioned above. The characteristics of chalcogenides and pniktides, obtained by the method of low-temperature calorimetry and by the method of high-temperature adiabatic calorimetry as well, are considered. A more detail estimate is made of the heat capacity component caused by expansion (that is of the most importance while considering the high-temperature data on heat capacity). The effect of energy levels of ions and atoms on heat capacity and a number of other problems are also considered. The approach to solution of these problems is illustrated on experimental data for a number of compounds, such as marcasite (FeS 2 ), low-temperature digenite (Csub(1.80)S), CoFe 2 , arsenides and antimonides of a number of metals (FeSb 2 , CrSb 2 , CrAs 2 , U 2 As 4 , U 3 Sb 4 , USb 2 , UAs 2 )

  6. Restriction endonucleases: classification, properties, and applications.

    Science.gov (United States)

    Williams, Raymond J

    2003-03-01

    Restriction endonucleases have become a fundamental tool of molecular biology with many commercial vendors and extensive product lines. While a significant amount has been learned about restriction enzyme diversity, genomic organization, and mechanism, these continue to be active areas of research and assist in classification efforts. More recently, one focus has been their exquisite specificity for the proper recognition sequence and the lack of homology among enzymes recognizing the same DNA sequence. Some questions also remain regarding in vivo function. Site-directed mutagenesis and fusion proteins based on known endonucleases show promise for custom-designed cleavage. An understanding of the enzymes and their properties can improve their productive application by maintaining critical digest parameters and enhancing or avoiding alternative activities.

  7. Biological Properties and Therapeutic Applications of Propolis.

    Science.gov (United States)

    Sforcin, José M

    2016-06-01

    Propolis is a resinous material collected by bees from bud and exudates of the plants, mixed with bee enzymes, pollen and wax. In this review, the biological properties of propolis and some therapeutic applications are discussed. The same biological activities have been investigated until today, using samples from different geographic regions. Thus, the study of the biological properties of a given sample should always be associated with its chemical composition and botanical source, representing a particular sample of a given geographic area, exploring its biological potential and the role of its constituents. Efforts have been carried out to explain propolis' mechanisms of action in vivo and in vitro, but the majority of propolis' targets and actions are still unclear. The number of formulations containing propolis and patents have increased, although propolis extracts have been used deliberately with different recommendations, not always mentioning the chemical composition, vegetal source and the methods of extraction. Clinical studies will help to obtain criterious recommendations in view of the expected outcomes. Further investigation should explore the effects of common compounds found in the samples from all over the world in an attempt to standardize the research on propolis and to obtain new drugs. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  8. Properties of leaves particleboard for sheathing application

    Science.gov (United States)

    Nuryawan, Arif; Rahmawaty

    2018-03-01

    Manufacturing particleboard (PB) made of leaves was carried out to make non-structural building components, such as insulation, partition, wall, and sheathing. Raw materials used dry leaves originated from plantation (palm oil leaves) and forest plantation (magahony leaves). The adhesive used was interior type thermosetting commercial resins, namely 10% urea-formaldehyde (UF) based on oven dry leaves. Hardener used for UF resin was 1% and 3% ammonium chloride (NH4Cl) 20% (w/w), respectively. Technically, the target density of PB was 0.8 g/cm3 with the dimension’s size of (250 x 250 x 10) mm3. The pressure, temperature, and time of pressing of the hot press were 25 kgf/cm2, 120C, and 10 minutes, respectively. After conditioning for one week, the PB then was evaluated their physical and mechanical properties according to Japanese Industrial Standard (JIS) A 5908 (2003). Results of this work showed: 1) Both types of PB (palm oil and mahagony leaves) were feasible to be produced for non-structural applications; 2) Addition of hardener enhanced the physical and mechanical properties of PB; 3) It was recommended to enhance the performance of the PB by manipulation of the raw materials and the design.

  9. Thermal and physical properties of bakery products.

    Science.gov (United States)

    Baik, O D; Marcotte, M; Sablani, S S; Castaigne, F

    2001-07-01

    This article reviews the measurement techniques, prediction models, and data on thermo-physical properties of bakery products: specific heat, thermal conductivity, thermal diffusivity, and density. Over the last decade, investigation has focused more on thermo-physical properties of nonbread bakery products. Both commonly used and new measurement techniques for thermo-physical properties reported in the publication are presented with directions for their proper use. Data and prediction models are tabulated for the range of moisture content and temperature of the bakery products.

  10. Amorphous and nanocrystalline materials preparation, properties, and applications

    CERN Document Server

    Inoue, A

    2001-01-01

    Amorphous and nanocrystalline materials are a class of their own. Their properties are quite different to those of the corresponding crystalline materials. This book gives systematic insight into their physical properties, structure, behaviour, and design for special advanced applications.

  11. Handbook of industrial refractories technology principles, types, properties and applications

    CERN Document Server

    Caniglia, Stephen

    1989-01-01

    Encompasses the entire range of industrial refractory materials and forms: properties and their measurement, applications, manufacturing, installation and maintenance techniques, quality assurance, and statistical process control.

  12. Thermophysical Characterization of MgCl2·6H2O, Xylitol and Erythritol as Phase Change Materials (PCM for Latent Heat Thermal Energy Storage (LHTES

    Directory of Open Access Journals (Sweden)

    Stephan Höhlein

    2017-04-01

    Full Text Available The application range of existing real scale mobile thermal storage units with phase change materials (PCM is restricted by the low phase change temperature of 58 ∘ C for sodium acetate trihydrate, which is a commonly used storage material. Therefore, only low temperature heat sinks like swimming pools or greenhouses can be supplied. With increasing phase change temperatures, more applications like domestic heating or industrial process heat could be operated. The aim of this study is to find alternative PCM with phase change temperatures between 90 and 150 ∘ C . Temperature dependent thermophysical properties like phase change temperatures and enthalpies, densities and thermal diffusivities are measured for the technical grade purity materials xylitol (C 5 H 12 O 5 , erythritol (C 4 H 10 O 4 and magnesiumchloride hexahydrate (MCHH, MgCl 2 · 6H 2 O. The sugar alcohols xylitol and erythritol indicate a large supercooling and different melting regimes. The salt hydrate MgCl 2 · 6H 2 O seems to be a suitable candidate for practical applications. It has a melting temperature of 115.1 ± 0.1 ∘ C and a phase change enthalpy of 166.9 ± 1.2 J / g with only 2.8 K supercooling at sample sizes of 100 g . The PCM is stable over 500 repeated melting and solidification cycles at differential scanning calorimeter (DSC scale with only small changes of the melting enthalpy and temperature.

  13. Thermophysical Characterization of MgCl2·6H2O, Xylitol and Erythritol as Phase Change Materials (PCM) for Latent Heat Thermal Energy Storage (LHTES)

    Science.gov (United States)

    Höhlein, Stephan; König-Haagen, Andreas; Brüggemann, Dieter

    2017-01-01

    The application range of existing real scale mobile thermal storage units with phase change materials (PCM) is restricted by the low phase change temperature of 58 ∘C for sodium acetate trihydrate, which is a commonly used storage material. Therefore, only low temperature heat sinks like swimming pools or greenhouses can be supplied. With increasing phase change temperatures, more applications like domestic heating or industrial process heat could be operated. The aim of this study is to find alternative PCM with phase change temperatures between 90 and 150 ∘C. Temperature dependent thermophysical properties like phase change temperatures and enthalpies, densities and thermal diffusivities are measured for the technical grade purity materials xylitol (C5H12O5), erythritol (C4H10O4) and magnesiumchloride hexahydrate (MCHH, MgCl2·6H2O). The sugar alcohols xylitol and erythritol indicate a large supercooling and different melting regimes. The salt hydrate MgCl2·6H2O seems to be a suitable candidate for practical applications. It has a melting temperature of 115.1 ± 0.1 ∘C and a phase change enthalpy of 166.9 ± 1.2 J/g with only 2.8 K supercooling at sample sizes of 100 g. The PCM is stable over 500 repeated melting and solidification cycles at differential scanning calorimeter (DSC) scale with only small changes of the melting enthalpy and temperature. PMID:28772806

  14. Thermophysical Characterization of MgCl₂·6H₂O, Xylitol and Erythritol as Phase Change Materials (PCM) for Latent Heat Thermal Energy Storage (LHTES).

    Science.gov (United States)

    Höhlein, Stephan; König-Haagen, Andreas; Brüggemann, Dieter

    2017-04-24

    The application range of existing real scale mobile thermal storage units with phase change materials (PCM) is restricted by the low phase change temperature of 58 ∘ C for sodium acetate trihydrate, which is a commonly used storage material. Therefore, only low temperature heat sinks like swimming pools or greenhouses can be supplied. With increasing phase change temperatures, more applications like domestic heating or industrial process heat could be operated. The aim of this study is to find alternative PCM with phase change temperatures between 90 and 150 ∘ C . Temperature dependent thermophysical properties like phase change temperatures and enthalpies, densities and thermal diffusivities are measured for the technical grade purity materials xylitol (C 5 H 12 O 5 ), erythritol (C 4 H 10 O 4 ) and magnesiumchloride hexahydrate (MCHH, MgCl 2 · 6H 2 O). The sugar alcohols xylitol and erythritol indicate a large supercooling and different melting regimes. The salt hydrate MgCl 2 · 6H 2 O seems to be a suitable candidate for practical applications. It has a melting temperature of 115.1 ± 0.1 ∘ C and a phase change enthalpy of 166.9 ± 1.2 J / g with only 2.8 K supercooling at sample sizes of 100 g . The PCM is stable over 500 repeated melting and solidification cycles at differential scanning calorimeter (DSC) scale with only small changes of the melting enthalpy and temperature.

  15. Thermophysics modeling of an infrared detector cryochamber for transient operational scenario

    Science.gov (United States)

    Singhal, Mayank; Singhal, Gaurav; Verma, Avinash C.; Kumar, Sushil; Singh, Manmohan

    2016-05-01

    An infrared detector (IR) is essentially a transducer capable of converting radiant energy in the infrared regime into a measurable form. The benefit of infrared radiation is that it facilitates viewing objects in dark or through obscured conditions by detecting the infrared energy emitted by them. One of the most significant applications of IR detector systems is for target acquisition and tracking of projectile systems. IR detectors also find widespread applications in the industry and commercial market. The performance of infrared detector is sensitive to temperatures and performs best when cooled to cryogenic temperatures in the range of nearly 120 K. However, the necessity to operate in such cryogenic regimes increases the complexity in the application of IR detectors. This entails a need for detailed thermophysics analysis to be able to determine the actual cooling load specific to the application and also due to its interaction with the environment. This will enable design of most appropriate cooling methodologies suitable for specific scenarios. The focus of the present work is to develop a robust thermo-physical numerical methodology for predicting IR cryochamber behavior under transient conditions, which is the most critical scenario, taking into account all relevant heat loads including radiation in its original form. The advantage of the developed code against existing commercial software (COMSOL, ANSYS, etc.), is that it is capable of handling gas conduction together with radiation terms effectively, employing a ubiquitous software such as MATLAB. Also, it requires much smaller computational resources and is significantly less time intensive. It provides physically correct results enabling thermal characterization of cryochamber geometry in conjunction with appropriate cooling methodology. The code has been subsequently validated experimentally as the observed cooling characteristics are found to be in close agreement with the results predicted using

  16. Thermophysical properties of sulfur heterocycles: Thiane and thiophene derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Temprado, Manuel [Instituto de Quimica Fisica ' Rocasolano' , CSIC, Serrano 119, 28006 Madrid (Spain); Roux, Maria Victoria [Instituto de Quimica Fisica ' Rocasolano' , CSIC, Serrano 119, 28006 Madrid (Spain)]. E-mail: victoriaroux@iqfr.csic.es; Jimenez, Pilar [Instituto de Quimica Fisica ' Rocasolano' , CSIC, Serrano 119, 28006 Madrid (Spain); Guzman-Mejia, Ramon [Departamento de Quimica, Centro de Investigacion y de Estudios Avanzados del IPN, Apartado Postal 14740, 07000 Mexico D.F. (Mexico); Juaristi, Eusebio [Departamento de Quimica, Centro de Investigacion y de Estudios Avanzados del IPN, Apartado Postal 14740, 07000 Mexico D.F. (Mexico)

    2006-02-01

    The present study reports a DSC study of the sulfur heterocyclic compounds: 2,2'-bithiophene [492-97-7]; 2,5-thiophenedicarboxylic acid [4282-31-9]; 3-acetylthiophene [1468-83-3]; 2-thiopheneacetic acid [1918-77-0]; 3-thiopheneacetic acid [6964-21-2]; 1,4-dithiane sulfone [139408-38-1]; 1,3-oxathiane-3,3-dioxide (1,3-oxathiane sulfone) [109577-03-9] and 1,4-oxathiane-4,4-dioxide (1,4-oxathiane sulfone) [107-61-9] in the temperature interval T = 268 K and the melting temperatures. Temperatures, enthalpies and entropies of fusion are reported. 1,4-Oxathiane sulfone presents solid-solid phase transitions near to fusion. No additional solid-solid phase transitions were observed for the other solid compounds. For the compounds that are solids over the temperature interval, the heat capacity of the condensed phase was measured. Heat capacities at T 298.15 K for the liquids 2-acetylthiophene [88-15-3]; methyl, 2-thiopheneacetate [19432-68-9]; methyl, 3-thiopheneacetate [58414-52-1] and thiazole [288-47-1] were also measured. The C {sub p,m} (298.15 K) values obtained in this work were compared with the available experimental data and with values estimated with group contribution schemes.

  17. Thermophysical properties and modeling of minor bodies regoliths

    Science.gov (United States)

    Delbo, M.

    2017-12-01

    I will review recent studies of atmosphere-less Solar System minor bodies in the thermal infrared wavelengths (> 5 micron), which have seen major advances in the last few years thanks to the observations from space telescopes such as NASA's WISE and Spitzer, JAXA's Akari and ESA's Herschel. Analysis of these observations by means of numerical models allowed not only the determination of sizes and albedos for more than hundred-thousands asteroids, but also to infer, for several of these objects, the values of their thermal inertia. The latter is a sensitive indicator for the presence (or absence) of surface regolith, its grain size, porosity, and degree of compaction. These data confirm presence of regolith on all the studied asteroids, even on the rapidly rotating (period thermal inertia inversely correlates with asteroid sizes, and directly correlates with their rotation periods. This can be explained by regolith density increasing with increasing depth below the surface, a phenomenon already noted of our moon. These findings will soon be tested with unprecedented detail by data from NASA's OSIRIS-REx sample return mission to the asteroid Bennu. OSIRIS-REx's instruments will map temperatures of the entire surface at different local times of the day (between 3:20am and 8:40pm) allowing fine sampling of the diurnal temperature curve. This will result in maps of the thermal inertia of the surface at 40 m spatial scale. On atmosphere-less bodies, thermal inertia controls the amplitude and rate of changes of temperature cycles, which can reach several tens of degrees and several degrees per minute, respectively. Laboratory experiments on materials analogs to those expected on asteroids show that these repeated temperature excursions cause stress on the materials, leading to their fragmentation and the production of fresh regolith

  18. Measurements of thermophysical properties of perfluorocarbons and ionic liquids

    OpenAIRE

    Carvalho, Pedro Jorge Marques de

    2008-01-01

    No presente trabalho propõe-se estudar a tensão superficial de vários perfluorocarbonetos lineares, cíclicos, aromáticos e [alfa]-substituídos bem como líquidos iónicos com o catião imidazolium em comum. Apesar do seu interesse inerente, informação sobre esta propriedade para os compostos seleccionados é escassa e quando disponível apresenta discrepâncias consideráveis entre si. As medições foram realizadas no intervalo de temperaturas (283 to 353) K usando o método do anel de Du Noüy. ...

  19. Electrical, thermoelectric and thermophysical properties of hornet cuticle

    Science.gov (United States)

    Galushko, D.; Ermakov, N.; Karpovski, M.; Palevski, A.; Ishay, J. S.; Bergman, D. J.

    2005-03-01

    Seebeck effect (thermo-emf), thermal conductivity and electrical conductivity of social hornet cuticle were measured in a direction perpendicular to the cuticular surface. The obtained value of the Seebeck coefficient (S) was about 3 ± 0.5 mV K-1 and its sign corresponded to an n-type (electronic) conductivity. Hornet cuticle is shown to be a fairly good heat insulator, with recorded values of the heat conductivity as low as 0.1-0.2 W m-1 K-1. The measured value of the electrical conductivity in the linear regime is σ = 8.5 × 10-5 Ω-1 cm-1. The thermoelectric figure of merit is computed. Implications for possible exploitation as a natural thermoelectric heat pump are discussed.

  20. Informatics and High Throughput Screening of Thermophysical Properties

    Science.gov (United States)

    Hyers, Robert W.; Rogers, Jan R.

    2008-01-01

    The combination of computer-aided experiments with computational modeling enables a new class of powerful tools for materials research. A non-contact method for measuring density, thermal expansion, and creep of undercooled and high-temperature materials has been developed, using electrostatic levitation and optical diagnostics, including digital video. These experiments were designed to take advantage of the large volume of data (many gigabytes/experiment, terabytes/campaign) to gain additional information about the samples. For example, using sub-pixel interpolation to measure about 1000 vectors per image of the sample's surface allows the density of an axisymmetric sample to be determined to an accuracy of about 200 ppm (0.02%). A similar analysis applied to the surface shape of a rapidly rotating sample is combined with finite element modeling to determine the stress-dependence of creep in the sample in a single test. Details of the methods for both the computer-aided experiments and computational models will be discussed.

  1. Thermophysical Property Measurements of Silicon-Transition Metal Alloys

    Science.gov (United States)

    Banish, R. Michael; Erwin, William R.; Sansoucie, Michael P.; Lee, Jonghyun; Gave, Matthew A.

    2014-01-01

    Metals and metallic alloys often have high melting temperatures and highly reactive liquids. Processing reactive liquids in containers can result in significant contamination and limited undercooling. This is particularly true for molten silicon and it alloys. Silicon is commonly termed "the universal solvent". The viscosity, surface tension, and density of several silicon-transition metal alloys were determined using the Electrostatic Levitator system at the Marshall Space Flight Center. The temperature dependence of the viscosity followed an Arrhenius dependence, and the surface tension followed a linear temperature dependence. The density of the melts, including the undercooled region, showed a linear behavior as well. Viscosity and surface tension values were obtain for several of the alloys in the undercooled region.

  2. Thermophysical properties of multi-shock compressed dense argon.

    Science.gov (United States)

    Chen, Q F; Zheng, J; Gu, Y J; Chen, Y L; Cai, L C; Shen, Z J

    2014-02-21

    In contrast to the single shock compression state that can be obtained directly via experimental measurements, the multi-shock compression states, however, have to be calculated with the aid of theoretical models. In order to determine experimentally the multiple shock states, a diagnostic approach with the Doppler pins system (DPS) and the pyrometer was used to probe multiple shocks in dense argon plasmas. Plasma was generated by a shock reverberation technique. The shock was produced using the flyer plate impact accelerated up to ∼6.1 km/s by a two-stage light gas gun and introduced into the plenum argon gas sample, which was pre-compressed from the environmental pressure to about 20 MPa. The time-resolved optical radiation histories were determined using a multi-wavelength channel optical transience radiance pyrometer. Simultaneously, the particle velocity profiles of the LiF window was measured with multi-DPS. The states of multi-shock compression argon plasma were determined from the measured shock velocities combining the particle velocity profiles. We performed the experiments on dense argon plasmas to determine the principal Hugonoit up to 21 GPa, the re-shock pressure up to 73 GPa, and the maximum measure pressure of the fourth shock up to 158 GPa. The results are used to validate the existing self-consistent variational theory model in the partial ionization region and create new theoretical models.

  3. Auxetic Polyurethane Foam (Fabrication, Properties and Applications)

    International Nuclear Information System (INIS)

    Yousif, H.I.Y.

    2012-01-01

    Modern technology requires new materials of special properties. For the last two decades there has been a great interest in a class of materials known as auxetic materials. An auxetic material is a material that has a negative Poisson's ratio which means that this material expands laterally when they subjected to a tensile force unlike most of the other traditional materials. This material has superior properties over the traditional material such as high shear modulus and high impact resistance, which makes this material a good candidate for many engineering applications. In the present research work, auxetic flexible polyurethane polymeric foams having different densities were fabricated from conventional flexible polyurethane polymeric foam at different compression ratios. The microstructure of conventional and processed foams was examined by optical microscope to compare between the two structures. The microstructure of processed foam was compared with the one presented in the literature and it has shown the auxetic structure configuration. This is the first time to produce auxetic foam in Egypt. Conventional and auxetic foam samples having cylindrical and square cross-sections were produced from foams having different densities (25 kg/m 3 and 30 kg/m 3 ). The compression ratios used to produce the auxetic samples are (5.56, 6.94 and 9.26). Four mechanical tests were carried out to get the mechanical properties for both conventional and auxetic foams. Two quasi-static mechanical tests t ension and compression a nd two dynamic mechanical tests H ysteresis and resilience w ere carried out to compare between the conventional and auxetic foams. The quasi-static tensile test was carried out at speed was adjusted to be position control rate of 0.2 mm/s. The compression and hysteresis tests were carried out at strain control rate of 0.3 S -1 . The data recorded from the machine were stress and strain. The modulus of elasticity and Poisson's ratio of the test

  4. Electrospun Ceramic Nanofiber Mats Today: Synthesis, Properties, and Applications

    Science.gov (United States)

    Esfahani, Hamid; Ramakrishna, Seeram

    2017-01-01

    Ceramic nanofibers (NFs) have recently been developed for advanced applications due to their unique properties. In this article, we review developments in electrospun ceramic NFs with regard to their fabrication process, properties, and applications. We find that surface activity of electrospun ceramic NFs is improved by post pyrolysis, hydrothermal, and carbothermal processes. Also, when combined with another surface modification methods, electrospun ceramic NFs result in the advancement of properties and widening of the application domains. With the decrease in diameter and length of a fiber, many properties of fibrous materials are modified; characteristics of such ceramic NFs are different from their wide and long (bulk) counterparts. In this article, electrospun ceramic NFs are reviewed with an emphasis on their applications as catalysts, membranes, sensors, biomaterials, fuel cells, batteries, supercapacitors, energy harvesting systems, electric and magnetic parts, conductive wires, and wearable electronic textiles. Furthermore, properties of ceramic nanofibers, which enable the above applications, and techniques to characterize them are briefly outlined. PMID:29077074

  5. Electrospun Ceramic Nanofiber Mats Today: Synthesis, Properties, and Applications

    Directory of Open Access Journals (Sweden)

    Hamid Esfahani

    2017-10-01

    Full Text Available Ceramic nanofibers (NFs have recently been developed for advanced applications due to their unique properties. In this article, we review developments in electrospun ceramic NFs with regard to their fabrication process, properties, and applications. We find that surface activity of electrospun ceramic NFs is improved by post pyrolysis, hydrothermal, and carbothermal processes. Also, when combined with another surface modification methods, electrospun ceramic NFs result in the advancement of properties and widening of the application domains. With the decrease in diameter and length of a fiber, many properties of fibrous materials are modified; characteristics of such ceramic NFs are different from their wide and long (bulk counterparts. In this article, electrospun ceramic NFs are reviewed with an emphasis on their applications as catalysts, membranes, sensors, biomaterials, fuel cells, batteries, supercapacitors, energy harvesting systems, electric and magnetic parts, conductive wires, and wearable electronic textiles. Furthermore, properties of ceramic nanofibers, which enable the above applications, and techniques to characterize them are briefly outlined.

  6. SOME PHYSICOCHEMICAL PROPERTIES AND APPLICATION OF ...

    African Journals Online (AJOL)

    The α-cellulose was also employed as disintegrant in some tablet formulations. Some of the physicochemical and flow properties evaluated were, moisture content, bulk density, packed density, Carrs compressibility, angle of repose and Hausner quotient. The tablet properties studied were, disintegration time, hardness, ...

  7. Alloys and composites of polybenzoxazines properties and applications

    CERN Document Server

    Rimdusit, Sarawut; Tiptipakorn, Sunan

    2013-01-01

    This book provides an introduction to the unique and fascinating properties of alloys and composites from novel commercialized thermosetting resins based on polybenzoxazines. Their outstanding properties such as processability, thermal, mechanical, electrical properties as well as ballistic impact properties of polybenzoxazine alloys and composites make them attractive for various applications in electronic packaging encapsulation, light weight ballistic armour composites and bipolar plate in fuel cells.

  8. Nanowires: properties, applications and synthesis via porous anodic ...

    Indian Academy of Sciences (India)

    Moreover, periodic arrays of magnetic nanowires hold high potential for recording media application. Nanowires are also potential candidates for sensor and bio-medical applications. In the present article, the physical and chemical properties of nanowires along with their probable applications in different fields have been ...

  9. Thermophysical modeling of main-belt asteroids from WISE data

    Science.gov (United States)

    Hanuš, J.; Delbó, M.; Durech, J.; Alí-Lagoa, V.

    2014-07-01

    We determine asteroid physical parameters such as size, surface roughness, albedo, and thermal inertia by applying the implementation of the thermophysical model (TPM) of Lagerros (1996; 1997; 1998) to the thermal data obtained by the NASA WISE satellite. We present thermophysical parameters for ˜150 asteroids, which gives us so far the largest sample of asteroids with determined values of thermal inertia. On several individual cases, we discuss the reliability of our determinations and limitations of the TPM method we use. As initial shapes, we adopt convex shape models from the DAMIT database (Durech et al., 2010) and present new determinations based on combined dense and sparse-in-time disk-integrated photometry and the lightcurve inversion method (Kaasalainen & Torppa 2001; Kaasalainen et al., 2001). We use thermal data from the WISE filters W3 and W4, as well as the data observed by the IRAS satellite. However, due to the intriguing accuracy of the fluxes and larger amount of measurements, the WISE data are significantly more important and dominate the modeling. The WISE data are processed the same way as in Alí-Lagoa et al. (2014) for asteroid (341 843) 2008 EV_5. We show the main results of the study of derived thermophysical parameters within the whole population of MBAs and within several asteroid families with the main focus on the thermal inertia. The thermal inertia increases with decreasing size (as previously shown by Delbó et al., 2007), but a large range of thermal inertia values is observed within the similar size ranges between D˜10-100 km. Surprisingly, we derived very low (<10 J m^{-2} s^{-1/2} K^{-1}) thermal inertias for many asteroids (˜20) with various sizes. The range of thermal inertia values is large even within a few asteroid families.

  10. Nanosilicon properties, synthesis, applications, methods of analysis and control

    CERN Document Server

    Ischenko, Anatoly A; Aslalnov, Leonid A

    2015-01-01

    Nanosilicon: Properties, Synthesis, Applications, Methods of Analysis and Control examines the latest developments on the physics and chemistry of nanosilicon. The book focuses on methods for producing nanosilicon, its electronic and optical properties, research methods to characterize its spectral and structural properties, and its possible applications. The first part of the book covers the basic properties of semiconductors, including causes of the size dependence of the properties, structural and electronic properties, and physical characteristics of the various forms of silicon. It presents theoretical and experimental research results as well as examples of porous silicon and quantum dots. The second part discusses the synthesis of nanosilicon, modification of the surface of nanoparticles, and properties of the resulting particles. The authors give special attention to the photoluminescence of silicon nanoparticles. The third part describes methods used for studying and controlling the structure and pro...

  11. Remote sensing application for property tax evaluation

    Science.gov (United States)

    Jain, Sadhana

    2008-02-01

    This paper presents a study for linking remotely sensed data with property tax related issues. First, it discusses the key attributes required for property taxation and evaluates the capabilities of remote sensing technology to measure these attributes accurately at parcel level. Next, it presents a detailed case study of six representative wards of different characteristics in Dehradun, India, that illustrates how measurements of several of these attributes supported by field survey can be combined to address the issues related to property taxation. Information derived for various factors quantifies the property taxation contributed by an average dwelling unit of the different income groups. Results show that the property tax calculated in different wards varies between 55% for the high-income group, 32% for the middle-income group, 12% for the low-income group and 1% for squatter units. The study concludes that higher spatial resolution satellite data and integrates social survey helps to assess the socio-economic status of the population for tax contribution purposes.

  12. PETher - Physical Properties of Thermal Water under In-situ-Conditions

    Science.gov (United States)

    Herfurth, Sarah; Schröder, Elisabeth

    2016-04-01

    The objective of PETher, a research project funded by the German Federal Ministry for Economic Affairs and Energy (BMWi), is to experimentally determine thermo-physical properties (specific isobaric heat capacity, kinematic viscosity, density and thermal conductivity) of geothermal water in-situ-conditions (pressure, temperature, chemical composition including gas content of the brine) present in geothermal applications. Knowing these thermo-physical properties reduces the uncertainties with respect to estimating the thermal output and therefore the economic viability of the power plant. Up to now, only a limited number of measurements of selected physical properties have been made, usually under laboratory conditions and for individual geothermal plants. In-situ measured parameters, especially in the temperature range of 120°C and higher, at pressures of 20 bar and higher, as well as with a salinity of up to 250 g/l, are sparse to non-existing. Therefore, pure water properties are often used as reference data and for designing the power plant and its components. Currently available numerical models describing the thermo-physical properties are typically not valid for the conditions in geothermal applications and do not consider the substantial influence of the chemical composition of the thermal water. Also, actual geothermal waters have not been subject of detailed measurements systematically performed under operational conditions on a large-scale basis. Owing to the lack of reliable data, a validation of numerical models for investigating geothermal systems is not possible. In order to determine the dependency of the thermo-physical properties of geothermal water on temperature, pressure and salinity in-situ measurements are conducted. The measurements are taking place directly at several geothermal applications located in Germany's hydrogeothermal key regions. In order to do this, a mobile testing unit was developed and refined with instruments specifically

  13. Thermophysical investigations of nanotechnological insulation materials

    Science.gov (United States)

    Lakatos, Ákos

    2017-07-01

    Nowadays, to sufficiently reduce the heat loss through the wall structures with the so-called traditional insulations (polystyrene and fibrous slabs), huge thicknesses (20 - 25 cm) must be applied. In some cases there is no place for their applications e.g.: historical or heritage builfings, since the use of nano-insulation materials (aerogel, vacuum ceramic paints) takes place. They are said to be much more efficient insulations than the above mentioned ones, since they should be used in thinner forms. In this article the thermal insulating capability of solid brick wall covered with a silica-aerogel slab with 1.3 cm, moreover with a vacuum ceramic hollow contained paint with 2 mm thick are investigated. As well as a literature review about the thermal conductivity of nano-technological insulation materials will be given. Comparison of the atomic and thermal diffusion will be also presented.

  14. Mechanical Properties of Composites Used in High-Voltage Applications

    Directory of Open Access Journals (Sweden)

    Andreas Moser

    2016-07-01

    Full Text Available Materials used in high voltage applications have to meet a lot of regulations for their safety and functional usage during their lifetime. For high voltage applications the electrical properties are the most relevant designing criteria. However, the mechanical properties of such materials have rarely been considered for application dimensioning over the last decades. This article gives an overview of composite materials used in high voltage applications and some basic mechanical and thermo-mechanical characterization methods of such materials, including a discussion of influences on practically used epoxy based thermosets.

  15. PVA hydrogel properties for biomedical application.

    Science.gov (United States)

    Jiang, Shan; Liu, Sha; Feng, Wenhao

    2011-10-01

    PVA has been proposed as a promising biomaterial suitable for tissue mimicking, vascular cell culturing and vascular implanting. In this research, a kind of transparent PVA hydrogel has been investigated in order to mimic the creatural soft tissue deformation during mini-invasive surgery with needle intervention, such as brachytherapy. Three kinds of samples with the same composition of 3 g PVA, 17 g de-ionized water, 80 g dimethyl-sulfoxide but different freeze/thaw cycles have been prepared. In order to investigate the structure and properties of polyvinyl alcohol hydrogel, micro-structure, mechanical property and deformation measurement have been conducted. As the SEM image comparison results show, with the increase of freeze/thaw cycles, PVA hydrogel revealed the similar micro-structure to porcine liver tissue. With uniaxial tensile strength test, the above composition with a five freeze/thaw cycle sample resulted in Young's modulus similar to that of porcine liver's property. Through the comparison of needle insertion deformation experiment and the clinical experiment during brachytherapy, results show that the PVA hydrogel had the same deformation property as prostate tissue. These transparent hydrogel phantom materials can be suitable soft tissue substitutes in needle intervention precision or pre-operation planning studies, particularly in the cases of mimicking creatural tissue deformation and analysing video camera images. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Detonation-synthesis nanodiamonds: synthesis, structure, properties and applications

    International Nuclear Information System (INIS)

    Dolmatov, Valerii Yu

    2007-01-01

    The review outlines the theoretical foundations and industrial implementations of modern detonation synthesis of nanodiamonds and chemical purification of the nanodiamonds thus obtained. The structure, key properties and promising fields of application of detonation-synthesis nanodiamonds are considered.

  17. PROPERTY DATABASE FOR THE DEVELOPMENT OF SHAPE MEMORY ALLOY APPLICATIONS

    OpenAIRE

    Tang , W.; CederstrÖm , J.; SandstrÖm , R.

    1991-01-01

    Important points involving the selection of shape memory alloy (SMA) application projects are discussed. The development of a property database for SMA is initiated. Both conventional data as well as characteristics which are unique for SMA are stored. As an application example of the database SMA-SELECT, important properties for Ti-Ni alloys near equi-atomic composition, such as temperature window width for superelasticity (SE), stress rate, critical yield stress, and their interaction have ...

  18. Inorganic biomaterials structure, properties and applications

    CERN Document Server

    Zhang, Xiang C

    2014-01-01

    This book provides a practical guide to the use and applications of inorganic biomaterials. It begins by introducing the concept of inorganic biomaterials, which includes bioceramics and bioglass. This concept is further extended to hybrid biomaterials consisting of inorganic and organic materials to mimic natural biomaterials. The book goes on to provide the reader with information on biocompatibility, bioactivity and bioresorbability. The concept of the latter is important because of the increasing role resorbable biomaterials are playing in implant applications. The book also introduces a n

  19. Colloidal Plasmonic Titanium Nitride Nanoparticles: Properties and Applications

    DEFF Research Database (Denmark)

    Guler, Urcan; Suslov, Sergey; Kildishev, Alexander V.

    2015-01-01

    Optical properties of colloidal plasmonic titanium nitride nanoparticles are examined with an eye on their photothermal and photocatalytic applications via transmission electron microscopy and optical transmittance measurements. Single crystal titanium nitride cubic nanoparticles with an average...... degree of freedom for surface functionalization. The titanium oxide shell surrounding the plasmonic core can create new opportunities for photocatalytic applications....

  20. Physically unclonable functions constructions, properties and applications

    CERN Document Server

    Maes, Roel

    2013-01-01

    Physically unclonable functions (PUFs) are innovative physical security primitives that produce unclonable and inherent instance-specific measurements of physical objects; in many ways they are the inanimate equivalent of biometrics for human beings. Since they are able to securely generate and store secrets, they allow us to bootstrap the physical implementation of an information security system. In this book the author discusses PUFs in all their facets: the multitude of their physical constructions, the algorithmic and physical properties which describe them, and the techniques required to

  1. Multifunctional Nanomaterials: Design, Synthesis and Application Properties

    Directory of Open Access Journals (Sweden)

    Marisa Martinelli

    2017-02-01

    Full Text Available The immense scope of variation in dendritic molecules (hyper-branching, nano-sized, hydrophobicity/hydrophilicity, rigidity/flexibility balance, etc. and their versatile functionalization, with the possibility of multivalent binding, permit the design of highly improved, novel materials. Dendritic-based materials are therefore viable alternatives to conventional polymers. The overall aim of this work is to show the advantages of dendronization processes by presenting the synthesis and characterization of three different dendronized systems: (I microbeads of functionalized chitosan; (II nanostructuration of polypropylene surfaces; and (III smart dendritic nanogels. The particular properties yielded by these systems could only be achieved thanks to the dendronization process.

  2. Nanoengineered silica: Properties, applications and toxicity.

    Science.gov (United States)

    Mebert, Andrea M; Baglole, Carolyn J; Desimone, Martin F; Maysinger, Dusica

    2017-11-01

    Silica nanoparticles are widely used for biomedical purposes, but also in cosmetic products, food, the car industry, paints, etc. Considering their mega production, one should not ignore their potential hazardous effects on humans, flora and fauna. Human exposure to nanosilica can occur unintentionally in daily life and in industrial settings. Here, we review the common methods of silica nanoparticle production and its applications in biomedical investigations and nanotoxicology. The use of silica nanoparticles in biomedicine is discussed in terms of drug delivery, their responsiveness to different stimuli, theranostic applications and their uses in the food and cosmetic industries. Advantages and limitations of silica nanoparticles are presented and the effects of these nanoparticles are discussed in relation to their route of entry and impact on biochemical and epigenetic processes in human and animal cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Lanthanum halide scintillators: Properties and applications

    International Nuclear Information System (INIS)

    Iltis, Alain; Mayhugh, M.R.; Menge, P.; Rozsa, C.M.; Selles, O.; Solovyev, V.

    2006-01-01

    BrilLanCe[reg]-350 and BrilLanCe[reg]-380, Saint-Gobain Crystals' trade-names for LaCl 3 :Ce and LaBr 3 :Ce are being brought to market under exclusive license to Delft and Bern Universities. We are reporting the properties of crystals produced with commercially viable processes and find they match others' observations. These scintillators are bright (60,000 photons/MeV for LaBr 3 :Ce) and have very linear response, a combination that leads to very good energy resolution ( 3 :Ce). The materials also have fast scintillation decay times ( 3 :Ce). These excellent properties are retained at high temperature with only moderate light loss ( 138 and Ac 227 , the latter having been substantially reduced in recent processing. BrilLanCe[reg]-350 is now available in detectors up to 51 mm diameter while 38 mm diameter is available for BrilLanCe[reg]-380. Larger sizes are expected

  4. Marine radar properties, analysis and applications

    OpenAIRE

    Kaspersen, Kai Magne

    2017-01-01

    In this thesis marine radars are compared with synthetic aperture radars (SAR) and the possibility of cross-over applications are investigated. A first cross-over has been demonstrated by using the TS-CFAR on marine radar images. The TS-CFAR was originally developed for SAR and is a constant false alarm rate (CFAR) detection algorithm based on truncated statistics. Detecting weak targets embedded in sea clutter is difficult because it is hard to find a model describing the sea in its various ...

  5. Tagatose: properties, applications, and biotechnological processes.

    Science.gov (United States)

    Oh, Deok-Kun

    2007-08-01

    D-Tagatose has attracted a great deal of attention in recent years due to its health benefits and similar properties to sucrose. D-Tagatose can be used as a low-calorie sweetener, as an intermediate for synthesis of other optically active compounds, and as an additive in detergent, cosmetic, and pharmaceutical formulation. Biotransformation of D-tagatose has been produced using several biocatalyst sources. Among the biocatalysts, L-arabinose isomerase has been mostly applied for D-tagatose production because of the industrial feasibility for the use of D-galactose as a substrate. In this article, the characterization of many L-arabinose isomerases and their D-tagatose production is compared. Protein engineering and immobilization of the enzyme for increasing the conversion rate of D-galactose to D-tagatose are also reviewed.

  6. Inulin: Properties, health benefits and food applications.

    Science.gov (United States)

    Shoaib, Muhammad; Shehzad, Aamir; Omar, Mukama; Rakha, Allah; Raza, Husnain; Sharif, Hafiz Rizwan; Shakeel, Azam; Ansari, Anum; Niazi, Sobia

    2016-08-20

    Inulin is a water soluble storage polysaccharide and belongs to a group of non-digestible carbohydrates called fructans. Inulin has attained the GRAS status in USA and is extensively available in about 36,000 species of plants, amongst, chicory roots are considered as the richest source of inulin. Commonly, inulin is used as a prebiotic, fat replacer, sugar replacer, texture modifier and for the development of functional foods in order to improve health due to its beneficial role in gastric health. This review provides a deep insight about its production, physicochemical properties, role in combating various kinds of metabolic and diet related diseases and utilization as a functional ingredient in novel product development. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Conducting polymer nanofibers: Synthesis, properties and applications

    Science.gov (United States)

    Huang, Jiaxing

    An interfacial polymerization method is described which enables the synthesis of polyaniline nanofibers with diameters tunable from 30 to 120 nm. This synthesis is template-free and readily scalable and can be applied to polyaniline derivatives and other conjugated polymers. Mechanistic studies reveal that nanofibers form naturally during the chemical oxidative polymerization of aniline in water without the need for any template, functional molecule or seed. In conventional polymerization, nanofibers are subject to secondary growth of amorphous particles which leads to irregularly shaped agglomerates. The key to producing pure nanofibers is to suppress secondary growth. This has been achieved with interfacial polymerization where the interface separates nanofiber formation from secondary growth and also by using rapidly mixed reactions where the initiator molecules are consumed before secondary growth begins. Polyaniline nanofibers dramatically enhance many applications of conventional polyaniline, such as in chemical sensors. Here, the small diameter, high surface area and water dispersibility of the nanofibers enable improved sensor performance and new sensing mechanisms. The nanofibers can also serve as a template to grow inorganic/polyaniline nanocomposites. Polyaniline nanofibers with 1--5 nm gold nanoparticles possess exciting applications such as in electronic non-volatile memory devices. Additionally, a novel flash welding technique for the nanofibers has been invented. A photographic camera flash sets off cross-linking reactions that can be used to make asymmetric polymer membranes, form patterned nanofiber films and create polymer based nanocomposites.

  8. Liquid Crystalline Semiconductors Materials, properties and applications

    CERN Document Server

    Kelly, Stephen; O'Neill, Mary

    2013-01-01

    This is an exciting stage in the development of organic electronics. It is no longer an area of purely academic interest as increasingly real applications are being developed, some of which are beginning to come on-stream. Areas that have already been commercially developed or which are under intensive development include organic light emitting diodes (for flat panel displays and solid state lighting), organic photovoltaic cells, organic thin film transistors (for smart tags and flat panel displays) and sensors. Within the family of organic electronic materials, liquid crystals are relative newcomers. The first electronically conducting liquid crystals were reported in 1988 but already a substantial literature has developed. The advantage of liquid crystalline semiconductors is that they have the easy processability of amorphous and polymeric semiconductors but they usually have higher charge carrier mobilities. Their mobilities do not reach the levels seen in crystalline organics but they circumvent all of t...

  9. Applications of modeling in polymer-property prediction

    Science.gov (United States)

    Case, F. H.

    1996-08-01

    A number of molecular modeling techniques have been applied for the prediction of polymer properties and behavior. Five examples illustrate the range of methodologies used. A simple atomistic simulation of small polymer fragments is used to estimate drug compatibility with a polymer matrix. The analysis of molecular dynamics results from a more complex model of a swollen hydrogel system is used to study gas diffusion in contact lenses. Statistical mechanics are used to predict conformation dependent properties — an example is the prediction of liquid-crystal formation. The effect of the molecular weight distribution on phase separation in polyalkanes is predicted using thermodynamic models. In some cases, the properties of interest cannot be directly predicted using simulation methods or polymer theory. Correlation methods may be used to bridge the gap between molecular structure and macroscopic properties. The final example shows how connectivity-indices-based quantitative structure-property relationships were used to predict properties for candidate polyimids in an electronics application.

  10. Gold nanocages: synthesis, properties, and applications.

    Science.gov (United States)

    Skrabalak, Sara E; Chen, Jingyi; Sun, Yugang; Lu, Xianmao; Au, Leslie; Cobley, Claire M; Xia, Younan

    2008-12-01

    Noble-metal nanocages comprise a novel class of nanostructures possessing hollow interiors and porous walls. They are prepared using a remarkably simple galvanic replacement reaction between solutions containing metal precursor salts and Ag nanostructures prepared through polyol reduction. The electrochemical potential difference between the two species drives the reaction, with the reduced metal depositing on the surface of the Ag nanostructure. In our most studied example, involving HAuCl(4) as the metal precursor, the resultant Au is deposited epitaxially on the surface of the Ag nanocubes, adopting their underlying cubic form. Concurrent with this deposition, the interior Ag is oxidized and removed, together with alloying and dealloying, to produce hollow and, eventually, porous structures that we commonly refer to as Au nanocages. This approach is versatile, with a wide range of morphologies (e.g., nanorings, prism-shaped nanoboxes, nanotubes, and multiple-walled nanoshells or nanotubes) available upon changing the shape of the initial Ag template. In addition to Au-based structures, switching the metal salt precursors to Na(2)PtCl(4) and Na(2)PdCl(4) allows for the preparation of Pt- and Pd-containing hollow nanostructures, respectively. We have found that changing the amount of metal precursor added to the suspension of Ag nanocubes is a simple means of tuning both the composition and the localized surface plasmon resonance (LSPR) of the metal nanocages. Using this approach, we are developing structures for biomedical and catalytic applications. Because discrete dipole approximations predicted that the Au nanocages would have large absorption cross-sections and because their LSPR can be tuned into the near-infrared (where the attenuation of light by blood and soft tissue is greatly reduced), they are attractive materials for biomedical applications in which the selective absorption of light at great depths is desirable. For example, we have explored their

  11. Recent advance in black phosphorus: Properties and applications

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yun, E-mail: zhaoyun@sit.edu.cn; Chen, Yong; Zhang, Ye-Hua; Liu, Shu-Feng

    2017-03-01

    Black phosphorus (BP) atomic layers, also called phosphorene, has triggered a recent renaissance of interest owing to its unique structure as well as fascinating optical and electronic properties. Several good reviews have been published in the past two years either concerning its physical and mechanical properties or electronic and optoelectronic applications. Herein, we offer our opinions from chemists' viewpoints on this emerging two-dimensional (2D) nano-material. A relatively comprehensive summarization for the recent advances of phosphorene is given, including the basic properties, fabrication features and promising applications especially the applications in chemical and biochemical analysis which have not been so widely mentioned in the past works. We also briefly discuss the drawbacks and limitations of phosphorene, and give a short outlook on the future directions. This tutorial review will be a desirable enlightenment for the new coming researchers and also inspire the fellow researchers to explore more appealing chemical characteristics and potentials of phosphorene especially toward chemical sensing and biochemical applications. - Highlights: • General knowledge about phosphorene is given, including structure and properties. • Different kinds of synthesis routes and characterization methods are compared. • Special emphasis are given on phosphorene's chemical or biochemical applications. • Device applications made with phosphorene-based hetero-hybrids are presented.

  12. RESEARCH OF PROPERTIES KIESELGUHR AS OBJECT OF THERMAL REGENERATION

    Directory of Open Access Journals (Sweden)

    D. M. Vizir

    2012-01-01

    Full Text Available The physico-mechanical and thermophysical properties of diatomite аre investigated. The equations, allowing to define characteristics of diatomite in a wide range of temperature and humidity are received.

  13. Technological advances in tellurite glasses properties, processing, and applications

    CERN Document Server

    Manzani, Danilo

    2017-01-01

    This book is the first to provide a comprehensive introduction to the synthesis, optical properties, and photonics applications of tellurite glasses. The book begins with an overview of tellurite glasses, followed by expert chapters on synthesis, properties, and state-of-the-art applications ranging from laser glass, optical fibers, and optical communications through color tuning, plasmonics, supercontinuum generation, and other photonic devices. The book provides in-depth information on the the structural, linear, and non-linear optical properties of tellurite glasses and their implications for device development. Real-world examples give the reader valuable insight into the applications of tellurite glass. A detailed discussion of glass production methods, including raw materials and melting and refining oxide- and fluoro-tellurite glasses, is also included. The book features an extensive reference list for further reading. This highly readable and didactic text draws on chemical composition, glass science,...

  14. The Mysteries of Diamonds: Bizarre History, Amazing Properties, Unique Applications

    Energy Technology Data Exchange (ETDEWEB)

    Kagan, Harris (Ohio State University)

    2008-06-24

    Diamonds have been a prized material throughout history. They are scarce and beautiful, wars have been fought over them, and they remain today a symbol of wealth and power. Diamonds also have exceptional physical properties which can lead to unique applications in science. There are now techniques to artificially synthesize diamonds of extraordinarily high quality. In this talk, Professor Kagan will discuss the history of diamonds, their bizarre properties, and their manufacture and use for 21st century science.

  15. Novel Dilute Bismide, Epitaxy, Physical Properties and Device Application

    Directory of Open Access Journals (Sweden)

    Lijuan Wang

    2017-02-01

    Full Text Available Dilute bismide in which a small amount of bismuth is incorporated to host III-Vs is the least studied III-V compound semiconductor and has received steadily increasing attention since 2000. In this paper, we review theoretical predictions of physical properties of bismide alloys, epitaxial growth of bismide thin films and nanostructures, surface, structural, electric, transport and optic properties of various binaries and bismide alloys, and device applications.

  16. Real-time measurement of materials properties at high temperatures by laser produced plasmas

    Science.gov (United States)

    Kim, Yong W.

    1990-01-01

    Determination of elemental composition and thermophysical properties of materials at high temperatures, as visualized in the context of containerless materials processing in a microgravity environment, presents a variety of unusual requirements owing to the thermal hazards and interferences from electromagnetic control fields. In addition, such information is intended for process control applications and thus the measurements must be real time in nature. A new technique is described which was developed for real time, in-situ determination of the elemental composition of molten metallic alloys such as specialty steel. The technique is based on time-resolved spectroscopy of a laser produced plasma (LPP) plume resulting from the interaction of a giant laser pulse with a material target. The sensitivity and precision were demonstrated to be comparable to, or better than, the conventional methods of analysis which are applicable only to post-mortem specimens sampled from a molten metal pool. The LPP technique can be applied widely to other materials composition analysis applications. The LPP technique is extremely information rich and therefore provides opportunities for extracting other physical properties in addition to the materials composition. The case in point is that it is possible to determine thermophysical properties of the target materials at high temperatures by monitoring generation and transport of acoustic pulses as well as a number of other fluid-dynamic processes triggered by the LPP event. By manipulation of the scaling properties of the laser-matter interaction, many different kinds of flow events, ranging from shock waves to surface waves to flow induced instabilities, can be generated in a controllable manner. Time-resolved detection of these events can lead to such thermophysical quantities as volume and shear viscosities, thermal conductivity, specific heat, mass density, and others.

  17. Structure, properties, and MEMS and microelectronic applications of ...

    Indian Academy of Sciences (India)

    Abstract. Vanadium oxides have for many decades attracted much attention for their rich and unique physical properties which pose intriguing questions as to their fundamental origins as well as offering numerous potential applications for microelectronics, sensors, and microelectromechanical systems (MEMS). This.

  18. Superconductors-A Review of Their Properties and Applications ...

    African Journals Online (AJOL)

    Superconductors are a special class of materials which exhibit a number of remarkable properties distinct from normal materials. These materials have found varied industrial and technological applications since the phenomenon of superconductivity was first discovered in 1911. A great deal of efforts are being made world ...

  19. Effect of biosolids application on soil chemical properties and uptake ...

    African Journals Online (AJOL)

    Effect of biosolids application on soil chemical properties and uptake of some heavy metals by Cercis siliquastrum. ... and municipal solid waste compost (50% CM + 50% MC) at three levels of 0, 2.5 and 5 kg/shrub and three replicates in calcareous sandy loam soil at the botanical garden of Mobarekeh steel company.

  20. Research progress on property and application of theaflavins ...

    African Journals Online (AJOL)

    Theaflavins is a group of very important material from black tea with functions as antioxidant, cancer suppressor and inhibitor of pathogenic microorgnisms. A discription is given on the property, chemical structure and application of theaflavin in this paper. The present research situation of theaflavins both in China and ...

  1. A new method of application of hydrated salts on textiles to achieve thermoregulating properties

    Energy Technology Data Exchange (ETDEWEB)

    Kazemi, Zeinab; Mortazavi, Sayed Majid, E-mail: mortaza@cc.iut.ac.ir

    2014-08-10

    Graphical abstract: - Highlights: • No need to microencapsulate the salt. • New method Glauber's salt dehydration. • Supercooling decreased, heat storage increased. - Abstract: Recently there has been a lot of attention to fibers and fabrics with thermoregulatory effects. We can acquire this quality using Phase Change Materials (PCM). In this investigation a simple method was used to keep Na{sub 2}SO{sub 4}·10H{sub 2}O as an inorganic PCM on textile structure. By this method it is not necessary for PCMs to be microencapsulated. Thermophysical properties and thermal stability effects of treated fabric was checked out by differential scanning calorimetry (DSC) and thermo gravimetric analysis (TGA). Fourier transform infrared spectroscopy (FT-IR) and X-ray diffractometry (XRD) analysis were used to study the chemical structure of the fabric with PCMs. The air transfer, water permeability, and some physical properties of treated fabric were also investigated. The results showed that, silicone rubber polymer could be applied on textile structure to hold PCM without microencapsulating, and treated textile can be served as an appropriate smart thermal insulator.

  2. A new method of application of hydrated salts on textiles to achieve thermoregulating properties

    International Nuclear Information System (INIS)

    Kazemi, Zeinab; Mortazavi, Sayed Majid

    2014-01-01

    Graphical abstract: - Highlights: • No need to microencapsulate the salt. • New method Glauber's salt dehydration. • Supercooling decreased, heat storage increased. - Abstract: Recently there has been a lot of attention to fibers and fabrics with thermoregulatory effects. We can acquire this quality using Phase Change Materials (PCM). In this investigation a simple method was used to keep Na 2 SO 4 ·10H 2 O as an inorganic PCM on textile structure. By this method it is not necessary for PCMs to be microencapsulated. Thermophysical properties and thermal stability effects of treated fabric was checked out by differential scanning calorimetry (DSC) and thermo gravimetric analysis (TGA). Fourier transform infrared spectroscopy (FT-IR) and X-ray diffractometry (XRD) analysis were used to study the chemical structure of the fabric with PCMs. The air transfer, water permeability, and some physical properties of treated fabric were also investigated. The results showed that, silicone rubber polymer could be applied on textile structure to hold PCM without microencapsulating, and treated textile can be served as an appropriate smart thermal insulator

  3. Methods of Recycling, Properties and Applications of Recycled Thermoplastic Polymers

    Directory of Open Access Journals (Sweden)

    Mădălina Elena Grigore

    2017-11-01

    Full Text Available This study aims to provide an updated survey of the main thermoplastic polymers in order to obtain recyclable materials for various industrial and indoor applications. The synthesis approach significantly impacts the properties of such materials and these properties in turn have a significant impact on their applications. Due to the ideal properties of the thermoplastic polymers such as corrosion resistance, low density or user-friendly design, the production of plastics has increased markedly over the last 60 years, becoming more used than aluminum or other metals. Also, recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today.

  4. Zinc oxide nanostructures: new properties for advances applications

    International Nuclear Information System (INIS)

    Lupan, Oleg; Chow, Lee; Pauporte, Thierry

    2011-01-01

    Zinc oxide is a material which exhibits a variety of new properties at nanometer dimensions. Various synthesis techniques have been carried out to provide growth of nanowires, nanorods, nanorings, nanosprings, and nanobelts of ZnO under various conditions. These nanostructures show that ZnO possesses probably the richest family of nanoarchitectures among all materials, including their structures and properties. Such nanoarchitectures are potential building blocks for novel applications in optoelectronics, sensors, photovoltaic and nano-biomedical sciences. This work presents a review of various nano architectures of ZnO grown by the electrochemical, hydrothermal and solid-vapor phase techniques and their properties. The possible applications of ZnO nanowires as sensors, nano-DSSC, photodetectors and nano-LEDs will be presented.

  5. Tangible nanocomposites with diverse properties for heart valve application

    Science.gov (United States)

    Vignesh Vellayappan, Muthu; Balaji, Arunpandian; Priyadarshini Subramanian, Aruna; Aruna John, Agnes; Jaganathan, Saravana Kumar; Murugesan, Selvakumar; Mohandas, Hemanth; Supriyanto, Eko; Yusof, Mustafa

    2015-06-01

    Cardiovascular disease claims millions of lives every year throughout the world. Biomaterials are used widely for the treatment of this fatal disease. With the advent of nanotechnology, the use of nanocomposites has become almost inevitable in the field of biomaterials. The versatile properties of nanocomposites, such as improved durability and biocompatibility, make them an ideal choice for various biomedical applications. Among the various nanocomposites, polyhedral oligomeric silsesquioxane-poly(carbonate-urea)urethane, bacterial cellulose with polyvinyl alcohol, carbon nanotubes, graphene oxide and nano-hydroxyapatite nanocomposites have gained popularity as putative choices for biomaterials in cardiovascular applications owing to their superior properties. In this review, various studies performed utilizing these nanocomposites for improving the mechanical strength, anti-calcification potential and hemocompatibility of heart valves are reviewed and summarized. The primary motive of this work is to shed light on the emerging nanocomposites for heart valve applications. Furthermore, we aim to promote the prospects of these nanocomposites in the campaign against cardiovascular diseases.

  6. Fuel Thermo-physical Characterization Project: Evaluation of Models to Calculate Thermal Diffusivity of Layered Composites

    Energy Technology Data Exchange (ETDEWEB)

    Burkes, Douglas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Amanda J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gardner, Levi D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Andrew M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Huber, Tanja K. [Technische Universität München, Munich (Germany); Breitkreutz, Harald [Technische Universität München, Munich (Germany)

    2015-02-11

    The Office of Material Management and Minimization Fuel Thermo-physical Characterization Project at Pacific Northwest National Laboratory (PNNL) is tasked with using PNNL facilities and processes to receive irradiated low enriched uranium-molybdenum fuel plate samples and perform analyses in support of the Office of Material Management and Minimization Reactor Conversion Program. This work is in support of the Fuel Development Pillar that is managed by Idaho National Laboratory. A key portion of the scope associated with this project was to measure the thermal properties of fuel segments harvested from plates that were irradiated in the Advanced Test Reactor. Thermal diffusivity of samples prepared from the fuel segments was measured using laser flash analysis. Two models, one developed by PNNL and the other developed by the Technische Universität München (TUM), were evaluated to extract the thermal diffusivity of the uranium-molybdenum alloy from measurements made on the irradiated, layered composites. The experimental data of the “TC” irradiated fuel segment was evaluated using both models considering a three-layer and five-layer system. Both models are in acceptable agreement with one another and indicate that the zirconium diffusion barrier has a minimal impact on the overall thermal diffusivity of the monolithic U-Mo fuel.

  7. Physiochemical properties and application of hyaluronic acid: a systematic review.

    Science.gov (United States)

    Salwowska, Natalia M; Bebenek, Katarzyna A; Żądło, Dominika A; Wcisło-Dziadecka, Dominika L

    2016-12-01

    Hyaluronic acid is a widely available, biocompatible, polysaccharide with distinguishing physiochemical properties which inspire its application throughout several fields of medicine. We aim to investigate the application of hyaluronic acid and its effectiveness throughout several fields of medicine, including several therapies administered and prescribed by general health practitioners. We conducted a systematic review on randomized controlled trials about the physiochemical properties of hyaluronic acid and its application through primary care. Studies included in this review were peer reviewed and met our inclusion criteria. Factors were clustered into the following: uses throughout several fields of medicine, physiochemical properties, bioavailability, tolerance, effectiveness, and adverse effects. Therapies with hyaluronic acid provided long-lasting, pain relieving, moisturizing, lubricating, and dermal filling effect. Tissue hydration, elasticity, and durability improved. Adjunct therapy with hyaluronic acid provides longer-lasting therapeutic effect when compared to the use of glucocorticosteroids and NSAIDs in osteoarthritic chronic diseases, is well-established in ophthalmology due to its lubricating properties for the corneal endothelium, and improves tissue hydration and cellular resistance to mechanical damage in aesthetic dermatology, and has marginal adverse effects. Several trials indicated its role in tumor markers, liver diseases, and in pharmaceuticals, but further research would be necessary to draw conclusive results in those fields. © 2016 Wiley Periodicals, Inc.

  8. Samarium Monosulfide (SmS): Reviewing Properties and Applications.

    Science.gov (United States)

    Sousanis, Andreas; Smet, Philippe F; Poelman, Dirk

    2017-08-16

    In this review, we give an overview of the properties and applications of samarium monosulfide, SmS, which has gained considerable interest as a switchable material. It shows a pressure-induced phase transition from the semiconducting to the metallic state by polishing, and it switches back to the semiconducting state by heating. The material also shows a magnetic transition, from the paramagnetic state to an antiferromagnetically ordered state. The switching behavior between the semiconducting and metallic states could be exploited in several applications, such as high density optical storage and memory materials, thermovoltaic devices, infrared sensors and more. We discuss the electronic, optical and magnetic properties of SmS, its switching behavior, as well as the thin film deposition techniques which have been used, such as e-beam evaporation and sputtering. Moreover, applications and possible ideas for future work on this material are presented. Our scope is to present the properties of SmS, which were mainly measured in bulk crystals, while at the same time we describe the possible deposition methods that will push the study of SmS to nanoscale dimensions, opening an intriguing range of applications for low-dimensional, pressure-induced semiconductor-metal transition compounds.

  9. Properties of Polymer Composites Used in High-Voltage Applications

    Directory of Open Access Journals (Sweden)

    Ilona Pleşa

    2016-04-01

    Full Text Available The present review article represents a comprehensive study on polymer micro/nanocomposites that are used in high-voltage applications. Particular focus is on the structure-property relationship of composite materials used in power engineering, by exploiting fundamental theory as well as numerical/analytical models and the influence of material design on electrical, mechanical and thermal properties. In addition to describing the scientific development of micro/nanocomposites electrical features desired in power engineering, the study is mainly focused on the electrical properties of insulating materials, particularly cross-linked polyethylene (XLPE and epoxy resins, unfilled and filled with different types of filler. Polymer micro/nanocomposites based on XLPE and epoxy resins are usually used as insulating systems for high-voltage applications, such as: cables, generators, motors, cast resin dry-type transformers, etc. Furthermore, this paper includes ample discussions regarding the advantages and disadvantages resulting in the electrical, mechanical and thermal properties by the addition of micro- and nanofillers into the base polymer. The study goals are to determine the impact of filler size, type and distribution of the particles into the polymer matrix on the electrical, mechanical and thermal properties of the polymer micro/nanocomposites compared to the neat polymer and traditionally materials used as insulation systems in high-voltage engineering. Properties such as electrical conductivity, relative permittivity, dielectric losses, partial discharges, erosion resistance, space charge behavior, electric breakdown, tracking and electrical tree resistance, thermal conductivity, tensile strength and modulus, elongation at break of micro- and nanocomposites based on epoxy resin and XLPE are analyzed. Finally, it was concluded that the use of polymer micro/nanocomposites in electrical engineering is very promising and further research work

  10. Thermal properties improvement of Lithium nitrate/Graphite composite phase change materials

    International Nuclear Information System (INIS)

    Lachheb, Mohamed; Adili, Ali; Albouchi, Fethi; Mzali, Foued; Ben Nasrallah, Sassi

    2016-01-01

    Highlights: • Preparation of new Lithium nitrate/Graphite PCM-composites. • Experimental investigation of the thermo-physical properties of PCM-composites. • Prediction of theoretical thermo-physical properties by using different analytical models. - Abstract: This paper addresses the development and the thermal investigation of new composite materials with improved thermo-physical properties destined for solar thermal energy storage at high temperature. The thermo-physical properties of composites are characterized by using several techniques based on the temperature measurement and the obtained results are compared to the theoretical values calculated by different analytical models. The results of these experiments revealed a clear improvement in the different thermal properties when integrating graphite particles in the composite. In the other hand, a good agreement between experimental and theoretical values was obtained.

  11. Colloidal Plasmonic Titanium Nitride Nanoparticles: Properties and Applications

    Directory of Open Access Journals (Sweden)

    Guler Urcan

    2015-01-01

    Full Text Available Optical properties of colloidal plasmonic titanium nitride nanoparticles are examined with an eye on their photothermal and photocatalytic applications via transmission electron microscopy and optical transmittance measurements. Single crystal titanium nitride cubic nanoparticles with an average size of 50 nm, which was found to be the optimum size for cellular uptake with gold nanoparticles [1], exhibit plasmon resonance in the biological transparency window and demonstrate a high absorption efficiency. A self-passivating native oxide at the surface of the nanoparticles provides an additional degree of freedom for surface functionalization. The titanium oxide shell surrounding the plasmonic core can create new opportunities for photocatalytic applications.

  12. Properties and medical applications of polylactic acid: A review

    Directory of Open Access Journals (Sweden)

    K. Hamad

    2015-05-01

    Full Text Available Polylactic acid (PLA, one of the well-known biodegradable polyesters, has been studied extensively for tissue engineering and drug delivery systems, and it was also used widely in human medicine. A new method to synthesize PLA (ring-opening polymerization, which allowed the economical production of a high molecular weight PLA polymer, broadened its applications, and this processing would be a potential substitute for petroleum-based products. This review described the principles of the polymerization reactions of PLA and, then, outlined the various materials properties affecting the performance of PLA polymer, such as rheological, mechanical, thermal, and barrier properties as well as the processing technologies which were used to fabricate products based on PLA. In addition, the biodegradation processes of products which were shaped from PLA were discussed and reviewed. The potential applications of PLA in the medical fields, such as tissue engineering, wound management, drugs delivery, and orthopedic devices, were also highlighted.

  13. Inorganic-whisker-reinforced polymer composites synthesis, properties and applications

    CERN Document Server

    Sun, Qiuju

    2015-01-01

    Inorganic-Whisker-Reinforced Polymer Composites: Synthesis, Properties and Applications gives a comprehensive presentation of inorganic microcrystalline fibers, or whiskers, a polymer composite filler. It covers whisker synthesis, surface modification, applications for reinforcing polymer-matrix composites, and analysis of resulting filled polymer composites. It focuses on calcium carbonate whiskers as a primary case study, introducing surface treatment methods for calcium carbonate whiskers and factors that influence them. Along with calcium carbonate, the book discusses potassium titanate and aluminum borate whiskers, which also comprise the new generation of inorganic whiskers. According to research results, composites filled by inorganic whiskers show improved strength, wear-resistance, thermal conductivity, and antistatic properties. It explains the importance of modifying polymer materials for use with inorganic whiskers and describes preparation and evaluation methods of polymers filled with inorganic ...

  14. Novel graphene-based nanostructures: physicochemical properties and applications

    International Nuclear Information System (INIS)

    Chernozatonskii, L A; Sorokin, P B; Artukh, A A

    2014-01-01

    The review concerns graphene-based nanostructures including graphene nanoribbons a few nanometres wide, structures functionalized with hydrogen and fluorine atoms as well as pure carbon composites. The physicochemical properties and the chemical engineering methods for their fabrication are considered. Methods for solving problems in modern nanotechnology are discussed. Possible applications of graphene and graphene-based nanostructures in various devices are outlined. The bibliography includes 286 references

  15. Properties and applications of ion-implanted alloys

    International Nuclear Information System (INIS)

    Myers, S.M.

    1979-01-01

    Ion implantation is a controlled and versatile means for near-surface alloying of metals. Supersaturated solutions, metastable compounds, amorphous phases, and equilibrium alloys have been produced. Uses include the investigation of new metastable phases, characterization of alloying reactions occurring in conventional materials, and improvement of surface properties such as hardness, wear, and corrosion. A brief review is given of the physical processes occurring during ion implantation, the types of alloys which result, and representative applications

  16. Recent advances in carbon nanodots: synthesis, properties and biomedical applications

    Science.gov (United States)

    Miao, Peng; Han, Kun; Tang, Yuguo; Wang, Bidou; Lin, Tao; Cheng, Wenbo

    2015-01-01

    Herein, a mini review is presented concerning the most recent research progress of carbon nanodots, which have emerged as one of the most attractive photoluminescent materials. Different synthetic methodologies to achieve advanced functions and better photoluminescence performances are summarized, which are mainly divided into two classes: top-down and bottom-up. The inspiring properties, including photoluminescence emission, chemiluminescence, electrochemical luminescence, peroxidase-like activity and toxicity, are discussed. Moreover, the biomedical applications in biosensing, bioimaging and drug delivery are reviewed.

  17. Applications and properties of thermally sprayed oxide ceramics

    International Nuclear Information System (INIS)

    Pawlowski, L.

    1991-01-01

    After a brief discussion of the general properties of thermally sprayed oxide ceramics, some of the more important materials are discussed in detail. The electric properties of Al 2 O 3 , such as electric resistivity, dielectric constant and dielectric strength, are shown together with the applications of thermally sprayed alumina coatings in 'corona rolls' and substrates in hybrid microelectronics. The thermal conductivity of ZrO 2 stabilized with a different Y 2 O 3 content is discussed together with the coatings' microstructure. The research on the development of zirconia coatings for application in the advanced turbines is briefly described. The mechanical properties of thermally sprayed Cr 2 O 3 coatings as well as their microstructure are shown. As chromia coatings often contain suboxides or even metallic chromium, a special powder giving metal free deposits has been developed and the coatings sprayed therefrom are applied in the printing industry as 'anilox rolls'. Finally, microstructure and some electrical properties of a high temperature superconductor YBa 2 CU 3 O 7-x are presented. (orig.) [de

  18. III–V Nanowires: Synthesis, Property Manipulations, and Device Applications

    Directory of Open Access Journals (Sweden)

    Ming Fang

    2014-01-01

    Full Text Available III–V semiconductor nanowire (NW materials possess a combination of fascinating properties, including their tunable direct bandgap, high carrier mobility, excellent mechanical flexibility, and extraordinarily large surface-to-volume ratio, making them superior candidates for next generation electronics, photonics, and sensors, even possibly on flexible substrates. Understanding the synthesis, property manipulation, and device integration of these III–V NW materials is therefore crucial for their practical implementations. In this review, we present a comprehensive overview of the recent development in III–V NWs with the focus on their cost-effective synthesis, corresponding property control, and the relevant low-operating-power device applications. We will first introduce the synthesis methods and growth mechanisms of III–V NWs, emphasizing the low-cost solid-source chemical vapor deposition (SSCVD technique, and then discuss the physical properties of III–V NWs with special attention on their dependences on several typical factors including the choice of catalysts, NW diameters, surface roughness, and surface decorations. After that, we present several different examples in the area of high-performance photovoltaics and low-power electronic circuit prototypes to further demonstrate the potential applications of these NW materials. Towards the end, we also make some remarks on the progress made and challenges remaining in the III–V NW research field.

  19. Magnetic nanoparticles: surface effects and properties related to biomedicine applications.

    Science.gov (United States)

    Issa, Bashar; Obaidat, Ihab M; Albiss, Borhan A; Haik, Yousef

    2013-10-25

    Due to finite size effects, such as the high surface-to-volume ratio and different crystal structures, magnetic nanoparticles are found to exhibit interesting and considerably different magnetic properties than those found in their corresponding bulk materials. These nanoparticles can be synthesized in several ways (e.g., chemical and physical) with controllable sizes enabling their comparison to biological organisms from cells (10-100 μm), viruses, genes, down to proteins (3-50 nm). The optimization of the nanoparticles' size, size distribution, agglomeration, coating, and shapes along with their unique magnetic properties prompted the application of nanoparticles of this type in diverse fields. Biomedicine is one of these fields where intensive research is currently being conducted. In this review, we will discuss the magnetic properties of nanoparticles which are directly related to their applications in biomedicine. We will focus mainly on surface effects and ferrite nanoparticles, and on one diagnostic application of magnetic nanoparticles as magnetic resonance imaging contrast agents.

  20. Graphitic carbon nitride: synthesis, properties, and applications in catalysis.

    Science.gov (United States)

    Zhu, Junjiang; Xiao, Ping; Li, Hailong; Carabineiro, Sónia A C

    2014-10-08

    Graphitic carbon nitride, g-C3N4, is a polymeric material consisting of C, N, and some impurity H, connected via tris-triazine-based patterns. Compared with the majority of carbon materials, it has electron-rich properties, basic surface functionalities and H-bonding motifs due to the presence of N and H atoms. It is thus regarded as a potential candidate to complement carbon in material applications. In this review, a brief introduction to g-C3N4 is given, the methods used for synthesizing this material with different textural structures and surface morphologies are described, and its physicochemical properties are referred. In addition, four aspects of the applications of g-C3N4 in catalysis are discussed: (1) as a base metal-free catalyst for NO decomposition, (2) as a reference material in differentiating oxygen activation sites for oxidation reactions over supported catalysts, (3) as a functional material to synthesize nanosized metal particles, and (4) as a metal-free catalyst for photocatalysis. The reasons for the use of g-C3N4 for such applications are also given, and we expect that this paper will inspire readers to search for further new applications for this material in catalysis and in other fields.

  1. Process, structure, property and applications of metallic glasses

    Directory of Open Access Journals (Sweden)

    B. Geetha Priyadarshini

    2016-07-01

    Full Text Available Metallic glasses (MGs are gaining immense technological significance due to their unique structure-property relationship with renewed interest in diverse field of applications including biomedical implants, commercial products, machinery parts, and micro-electro-mechanical systems (MEMS. Various processing routes have been adopted to fabricate MGs with short-range ordering which is believed to be the genesis of unique structure. Understanding the structure of these unique materials is a long-standing unsolved mystery. Unlike crystalline counterpart, the outstanding properties of metallic glasses owing to the absence of grain boundaries is reported to exhibit high hardness, excellent strength, high elastic strain, and anti-corrosion properties. The combination of these remarkable properties would significantly contribute to improvement of performance and reliability of these materials when incorporated as bio-implants. The nucleation and growth of metallic glasses is driven by thermodynamics and kinetics in non-equilibrium conditions. This comprehensive review article discusses the various attributes of metallic glasses with an aim to understand the fundamentals of relationship process-structure-property existing in such unique class of material.

  2. Carbon-Based Wear Coatings: Properties and Applications

    Science.gov (United States)

    Miyoshi, Kazuhisa

    2003-01-01

    The technical function of numerous engineering systems - such as vehicles, machines, and instruments - depends on the processes of motion and on the surface systems. Many processes in nature and technology depend on the motion and dynamic behavior of solids, liquids, and gases. Smart surface systems are essential because of the recent technological push toward higher speeds, loads, and operating temperatures; longer life; lighter weight and smaller size (including nanotechnology); and harsh environments in mechanical, mechatronic, and biomechanical systems. If proper attention is not given to surface systems, then vehicles, machines, instruments, and other technical systems could have short lives, consume excessive energy, experience breakdowns, result in liabilities, and fail to accomplish their missions. Surface systems strongly affect our national economy and our lifestyles. At the NASA Glenn Research Center, we believe that proper attention to surface systems, especially in education, research, and application, could lead to economic savings of between 1.3 and 1.6 percent of the gross domestic product. Wear coatings and surface systems continue to experience rapid growth as new coating and surface engineering technologies are discovered, more cost-effective coating and surface engineering solutions are developed, and marketers aggressively pursue, uncover, and exploit new applications for engineered surface systems in cutting tools and wear components. Wear coatings and smart surface systems have been used widely in industrial, consumer, automotive, aerospace, and biomedical applications. This presentation expresses the author's views of and insights into smart surface systems in wear coatings. A revolution is taking place in carbon science and technology. Diamond, an allotrope of carbon, joins graphite, fullerenes, and nanotubes as its major pure carbon structures. It has a unique combination of extreme properties: hardness and abrasion resistance; adhesion

  3. Feasibility and Accuracy of Thermophysical Estimation of Asteroid 162173 Ryugu (1999 JU3) from the Hayabusa2 Thermal Infrared Imager

    Science.gov (United States)

    Takita, Jun; Senshu, Hiroki; Tanaka, Satoshi

    2017-07-01

    We present the results of a numerical study to prepare for the remote sensing of asteroid 162173 Ryugu (1999 JU3) using the Hayabusa2 thermal infrared imager (TIR). We simulated the thermal characteristics of the asteroid with a thermophysical model (TPM) using an ideal body with a smooth and spherical surface, and investigated its feasibility to determine the thermophysical properties of the asteroid under two possible spin vectors; (λ_{ecl}, β_{ecl}) = (73°, -62°) and (331°, 20°). Each of the simulated snapshots taken at various local times during the 1.5-year proximity phase was analyzed to estimate uncertainties of the diurnal thermal phase delay to infer the thermal inertia of Ryugu. The temperature in a pixel was simulated based on the specification of the imager and the observing geometry. Moreover, we carried out a regression analysis to estimate albedo and thermal emissivity from the time variation of surface temperature. We also investigated the feasibility of determining thermal phase delay in a first attempt using realistic rough surfaces. We found that precise determination of the thermal phase delay would be difficult in the (331°, 20°) spin type unless the surface was nearly smooth. In contrast, the thermal phase delay is likely to be observable even if the surface topography is moderately rough in the other spin type. From the smooth-surface model, we obtained a less than 20% error of thermal inertia on observation opportunities under the likely range of thermal inertia ≤ 1000 J m^{-2} s^{-1/2} K^{-1}. The error of thermal inertia exceeded 50% under a realistic surface with roughness.

  4. Optical properties and applications of dendrimer-metal nanocomposites

    Science.gov (United States)

    Goodson, T.; Varnavski, O.; Wang, Y.

    The use of novel nanostructured materials for optical applications continues to be an important issue for the creation of new devices. New materials including metal nanoparticles have played an important role for applications in photonics, biology, as well as medicine. This review primarily concerns the use of one particular metal nanoparticle topology, dendrimer-metal nanocomposites. The focus of this review is to describe the optical properties of dendrimer-metal nanocomposites as well as functionalized dendrimer-metal nanocomposites. The description of various synthetic methodologies to produce transition metal (Au, Ag, Pd, Pt, and Cu) dendrimer nanocomposites as well as lanthanide ion-cored dendrimers are presented in this review, with further details regarding the basic characterization of these systems. The experimental procedures of the optical measurements used to probe the steady-state and time-resolved dynamics in these novel nanoparticle architectures are provided. Analysis of optical properties of dendrimer nanocomposites (DNCs) includes a description of the characterization of the metal nanoparticles as well as the size and distribution of metal nanoparticles formed by use of organic dendrimer template synthetic procedures (such as PAMAM). The non-linear transmission properties of certain dendrimer-metal nanocomposites show promising behaviour, which may be useful for applications involving eye and sensor protection. Reports of non-linear transmission properties of both Au and Ag dendrimer nanocomposites are discussed. Metal nanoparticles have also been suggested as useful materials for biological fluorescence imaging and sensing applications. However, it is well known that the efficiency of metal emission is very small. Recent measurements using ultra-fast spectroscopic techniques (fluorescence upconversion) have shed new light on this matter in metal nanoparticles and in dendrimer-metal nanocomposites. Dendrimer-metal nanocomposites have been used to

  5. Polycaprolactone/starch composite: Fabrication, structure, properties, and applications.

    Science.gov (United States)

    Ali Akbari Ghavimi, Soheila; Ebrahimzadeh, Mohammad H; Solati-Hashjin, Mehran; Abu Osman, Noor Azuan

    2015-07-01

    Interests in the use of biodegradable polymers as biomaterials have grown. Among the different polymeric composites currently available, the blend of starch and polycaprolactone (PCL) has received the most attention since the 1980s. Novamont is the first company that manufactured a PCL/starch (SPCL) composite under the trademark Mater-Bi®. The properties of PCL (a synthetic, hydrophobic, flexible, expensive polymer with a low degradation rate) and starch (a natural, hydrophilic, stiff, abundant polymer with a high degradation rate) blends are interesting because of the composite components have completely different structures and characteristics. PCL can adjust humidity sensitivity of starch as a biomaterial; while starch can enhance the low biodegradation rate of PCL. Thus, by appropriate blending, SPCL can overcome important limitations of both PCL and starch components and promote controllable behavior in terms of mechanical properties and degradation which make it suitable for many biomedical applications. This article reviewed the different fabrication and modification methods of the SPCL composite; different properties such as structural, physical, and chemical as well as degradation behavior; and different applications as biomaterials. © 2014 Wiley Periodicals, Inc.

  6. Tangible nanocomposites with diverse properties for heart valve application

    International Nuclear Information System (INIS)

    Vellayappan, Muthu Vignesh; Balaji, Arunpandian; Subramanian, Aruna Priyadarshini; John, Agnes Aruna; Jaganathan, Saravana Kumar; Supriyanto, Eko; Yusof, Mustafa; Murugesan, Selvakumar; Mohandas, Hemanth

    2015-01-01

    Cardiovascular disease claims millions of lives every year throughout the world. Biomaterials are used widely for the treatment of this fatal disease. With the advent of nanotechnology, the use of nanocomposites has become almost inevitable in the field of biomaterials. The versatile properties of nanocomposites, such as improved durability and biocompatibility, make them an ideal choice for various biomedical applications. Among the various nanocomposites, polyhedral oligomeric silsesquioxane-poly(carbonate-urea)urethane, bacterial cellulose with polyvinyl alcohol, carbon nanotubes, graphene oxide and nano-hydroxyapatite nanocomposites have gained popularity as putative choices for biomaterials in cardiovascular applications owing to their superior properties. In this review, various studies performed utilizing these nanocomposites for improving the mechanical strength, anti-calcification potential and hemocompatibility of heart valves are reviewed and summarized. The primary motive of this work is to shed light on the emerging nanocomposites for heart valve applications. Furthermore, we aim to promote the prospects of these nanocomposites in the campaign against cardiovascular diseases. (review)

  7. Infrared colloidal lead chalcogenide nanocrystals: synthesis, properties, and photovoltaic applications.

    Science.gov (United States)

    Fu, Huiying; Tsang, Sai-Wing

    2012-04-07

    Simple solution phase, catalyst-free synthetic approaches that offer monodispersed, well passivated, and non-aggregated colloidal semiconductor nanocrystals have presented many research opportunities not only for fundamental science but also for technological applications. The ability to tune the electrical and optical properties of semiconductor nanocrystals by manipulating the size and shape of the crystals during the colloidal synthesis provides potential benefits to a variety of applications including photovoltaic devices, light-emitting diodes, field effect transistors, biological imaging/labeling, and more. Recent advances in the synthesis and characterization of colloidal lead chalcogenide nanocrystals and the achievements in colloidal PbS or PbSe nanocrystals solar cells have demonstrated the promising application of infrared-emitting colloidal lead chalcogenide nanocrystals in photovoltaic devices. Here, we review recent progress in the synthesis and optical properties of colloidal lead chalcogenide nanocrystals. We focus in particular upon the size- and shape-controlled synthesis of PbS, PbSe, and PbTe nanocrystals by using different precursors and various stabilizing surfactants for the growth of the colloidal nanocrystals. We also summarize recent advancements in the field of colloidal nanocrystals solar cells based on colloidal PbS and PbSe nanocrystals. This journal is © The Royal Society of Chemistry 2012

  8. Infrared colloidal lead chalcogenide nanocrystals: Synthesis, properties, and photovoltaic applications

    Science.gov (United States)

    Fu, Huiying; Tsang, Sai-Wing

    2012-03-01

    Simple solution phase, catalyst-free synthetic approaches that offer monodispersed, well passivated, and non-aggregated colloidal semiconductor nanocrystals have presented many research opportunities not only for fundamental science but also for technological applications. The ability to tune the electrical and optical properties of semiconductor nanocrystals by manipulating the size and shape of the crystals during the colloidal synthesis provides potential benefits to a variety of applications including photovoltaic devices, light-emitting diodes, field effect transistors, biological imaging/labeling, and more. Recent advances in the synthesis and characterization of colloidal lead chalcogenide nanocrystals and the achievements in colloidal PbS or PbSe nanocrystals solar cells have demonstrated the promising application of infrared-emitting colloidal lead chalcogenide nanocrystals in photovoltaic devices. Here, we review recent progress in the synthesis and optical properties of colloidal lead chalcogenide nanocrystals. We focus in particular upon the size- and shape-controlled synthesis of PbS, PbSe, and PbTe nanocrystals by using different precursors and various stabilizing surfactants for the growth of the colloidal nanocrystals. We also summarize recent advancements in the field of colloidal nanocrystals solar cells based on colloidal PbS and PbSe nanocrystals.

  9. Magnesium Matrix Composite Foams—Density, Mechanical Properties, and Applications

    Directory of Open Access Journals (Sweden)

    Kyu Cho

    2012-07-01

    Full Text Available Potential of widespread industrial applications of magnesium has been realized in recent years. A variety of magnesium alloy matrix composites are now being studied for mechanical properties. Since magnesium is the lightest structural metal, it can replace aluminum in existing applications for further weight savings. This review presents an overview of hollow particle filled magnesium matrix syntactic composite foams. Fly ash cenospheres are the most commonly used hollow particles for such applications. Fly ash cenospheres primarily have alumino-silicate composition and contain a large number of trace elements, which makes it challenging to study the interfacial reactions and microstructure in these composites. Microstructures of commonly studied AZ and ZC series magnesium alloys and their syntactic foams are discussed. Although only a few studies are available on these materials because of the nascent stage of this field, a comparison with similar aluminum matrix syntactic foams has provided insight into the properties and weight saving potential of magnesium matrix composites. Analysis shows that the magnesium matrix syntactic foams have higher yield strength at the same level of density compared to most other metal matrix syntactic foams. The comparison can guide future work and set goals that need to be achieved through materials selection and processing method development.

  10. Barthel index for stroke trials: development, properties, and application.

    Science.gov (United States)

    Quinn, Terence J; Langhorne, Peter; Stott, David J

    2011-04-01

    Robust measures of functional outcome are required to determine treatment effects in stroke trials. Of the various measures available, the Barthel index (BI) is one of the more prevalent. We aimed to describe validity, reliability, and responsiveness (clinimetric properties) of the BI in stroke trials. Narrative review of published articles describing clinimetric properties or use of the BI as a stroke trial end point. Definitive statements on properties of BI are limited by heterogeneity in methodology of assessment and in the content of "BI" scales. Accepting these caveats, evidence suggests that BI is a valid measure of activities of daily living; sensitivity to change is limited at extremes of disability (floor and ceiling effects), and reliability of standard BI assessment is acceptable. However, these data may not be applicable to contemporary multicenter stroke trials. Substantial literature describing BI clinimetrics in stroke is available; however, questions remain regarding certain properties. The "BI" label is used for a number of instruments and we urge greater consistency in methods, content, and scoring. A 10-item scale, scoring 0 to 100 with 5-point increments, has been used in several multicenter stroke trials and it seems reasonable that this should become the uniform stroke trial BI.

  11. Engineering Biomaterial Properties for Central Nervous System Applications

    Science.gov (United States)

    Rivet, Christopher John

    Biomaterials offer unique properties that are intrinsic to the chemistry of the material itself or occur as a result of the fabrication process; iron oxide nanoparticles are superparamagnetic, which enables controlled heating in the presence of an alternating magnetic field, and a hydrogel and electrospun fiber hybrid material provides minimally invasive placement of a fibrous, artificial extracellular matrix for tissue regeneration. Utilization of these unique properties towards central nervous system disease and dysfunction requires a thorough definition of the properties in concert with full biological assessment. This enables development of material-specific features to elicit unique cellular responses. Iron oxide nanoparticles are first investigated for material-dependent, cortical neuron cytotoxicity in vitro and subsequently evaluated for alternating magnetic field stimulation induced hyperthermia, emulating the clinical application for enhanced chemotherapy efficacy in glioblastoma treatment. A hydrogel and electrospun fiber hybrid material is first applied to a rat brain to evaluate biomaterial interface astrocyte accumulation as a function of hybrid material composition. The hybrid material is then utilized towards increasing functional engraftment of dopaminergic progenitor neural stem cells in a mouse model of Parkinson's disease. Taken together, these two scenarios display the role of material property characterization in development of biomaterial strategies for central nervous system repair and regeneration.

  12. Understanding Materials Science History · Properties · Applications

    CERN Document Server

    Hummel, Rolf E

    2005-01-01

    This introduction to materials science both for students of engineering and physics and for the interested general public examines not only the physical and engineering properties of virtually all kinds of materials, but also their history, uses, development, and some of the implications of resource depletion and recycling. It covers all topics on materials from an entirely novel perspective: the role materials have played throughout history in the development of humankind and technologies. Specifically, it shows the connection between the technical and the cultural, economic, ecological, and societal aspects of materials science. It aims to whet the appetite of its readers and inspire them to further explore the properties and applications of metals, alloys, ceramics, plastics, and electronic materials by presenting easily understandable explanations and entertaining historical facts. It is also intended to raise the reader’s awareness of their obligations to society as practicing engineers and scientists....

  13. Archetypal tryptophan-rich antimicrobial peptides: properties and applications.

    Science.gov (United States)

    Shagaghi, Nadin; Palombo, Enzo A; Clayton, Andrew H A; Bhave, Mrinal

    2016-02-01

    Drug-resistant microorganisms ('superbugs') present a serious challenge to the success of antimicrobial treatments. Subsequently, there is a crucial need for novel bio-control agents. Many antimicrobial peptides (AMPs) show a broad-spectrum activity against bacteria, fungi or viruses and are strong candidates to complement or substitute current antimicrobial agents. Some AMPs are also effective against protozoa or cancer cells. The tryptophan (Trp)-rich peptides (TRPs) are a subset of AMPs that display potent antimicrobial activity, credited to the unique biochemical properties of tryptophan that allow it to insert into biological membranes. Further, many Trp-rich AMPs cross bacterial membranes without compromising their integrity and act intracellularly, suggesting interactions with nucleic acids and enzymes. In this work, we overview some archetypal TRPs derived from natural sources, i.e., indolicidin, tritrpticin and lactoferricin, summarising their biochemical properties, structures, antimicrobial activities, mechanistic studies and potential applications.

  14. Two-dimensional carbon fundamental properties, synthesis, characterization, and applications

    CERN Document Server

    Yihong, Wu; Ting, Yu

    2013-01-01

    After a brief introduction to the fundamental properties of graphene, this book focuses on synthesis, characterization and application of various types of two-dimensional (2D) nanocarbons ranging from single/few layer graphene to carbon nanowalls and graphene oxides. Three major synthesis techniques are covered: epitaxial growth of graphene on SiC, chemical synthesis of graphene on metal, and chemical vapor deposition of vertically aligned carbon nanosheets or nanowalls. One chapter is dedicated to characterization of 2D nanocarbon using Raman spectroscopy. It provides extensive coverage for a

  15. Metal Oxide Nano structures: Synthesis, Properties, and Applications

    International Nuclear Information System (INIS)

    Xu, L. H.; Patil, D. S.; Yang, J.; Xiao, J.

    2015-01-01

    In recent years, nano structured materials have attracted wide attention due to their fascinating optical and electrical properties, which make these materials potentially suitable for applications in electronics, optics, photonics, and sensors. Some metal oxides show a wide variety of morphologies such as nano wires, nano rods, nano tubes, nano rings, and nano belts. Synthesis and investigation of these metal-oxide nano structures are beneficial not only for understanding the fundamental phenomena in low dimensional systems, but also for developing new-generation nano devices with high performance.

  16. Radio-frequency quadrupole: general properties and specific applications

    International Nuclear Information System (INIS)

    Stokes, R.H.; Crandall, K.R.; Hamm, R.W.

    1980-01-01

    The radio-frequency quadrupole (RFQ) linac structure is being developed for the acceleration of low-velocity ions. Recent experimental tests have confirmed its expected performance and have led to an increased interest in a wide range of possible applications. The general properties of RFQ accelerators are reviewed and beam dynamics simulation results are presented for their use in a variety of accelerating systems. These include the low-beta sections of the Fusion Materials Irradiation Test Accelerator, a 200-MHz proton linear accelerator, and a xenon accelerator for heavy ion fusion

  17. Tuning CNT Properties for Metal-Free Environmental Catalytic Applications

    Directory of Open Access Journals (Sweden)

    Raquel P. Rocha

    2016-06-01

    Full Text Available The application of carbon nanotubes (CNTs as metal-free catalysts is a novel approach for heterogeneous liquid phase catalytic systems. Textural and chemical modifications by liquid/gas phase or mechanical treatments, as well as solid state reactions, were successfully applied to obtain carbon nanotubes with different surface functionalities. Oxygen, nitrogen, and sulfur are the most common heteroatoms introduced on the carbon surface. This short-review highlights different routes used to develop metal-free carbon nanotube catalysts with enhanced properties for Advanced Oxidation Processes.

  18. Length-Biased Weighted Lomax Distribution: Statistical Properties and Application

    Directory of Open Access Journals (Sweden)

    Afaq Ahmad

    2016-06-01

    Full Text Available The concept of length-biased distribution can be employed in development of proper models for lifetime data. Length-biased distribution is a special case of the more general form known as weighted distribution. In this paper we introduce a new class of length-biased weighted Lomax distribution, (LBWLD. The statistical properties of this distribution are derived and the model parameters are estimated by maximum likelihood estimation and the observed information matrix is determined. An application to real data set is finally presented for illustration.

  19. Synthesis, Properties Characterization and Applications of Various Organobismuth Compounds

    Directory of Open Access Journals (Sweden)

    Jingfei Luan

    2011-05-01

    Full Text Available Organobismuth chemistry was emphasized in this review article due to the low price, low toxicity and low radioactivity characteristics of bismuth. As an environmentally-friendly class of organometallic compounds, different types of organobismuth compounds have been used in organic synthesis, catalysis, materials, etc. The synthesis and property characterization of many organobismuth compounds had been summarized. This review article also presented a survey of various applications of organobismuth compounds in organic transformations, as reagents or catalysts. The reactivity, reaction pathways and mechanisms of reactions with organobismuths were discussed. Less common and limiting aspects of organobismuth compounds were also briefly mentioned.

  20. Machine Learning Identification of Protein Properties Useful for Specific Applications

    KAUST Repository

    Khamis, Abdullah

    2016-03-31

    Proteins play critical roles in cellular processes of living organisms. It is therefore important to identify and characterize their key properties associated with their functions. Correlating protein’s structural, sequence and physicochemical properties of its amino acids (aa) with protein functions could identify some of the critical factors governing the specific functionality. We point out that not all functions of even well studied proteins are known. This, complemented by the huge increase in the number of newly discovered and predicted proteins, makes challenging the experimental characterization of the whole spectrum of possible protein functions for all proteins of interest. Consequently, the use of computational methods has become more attractive. Here we address two questions. The first one is how to use protein aa sequence and physicochemical properties to characterize a family of proteins. The second one focuses on how to use transcription factor (TF) protein’s domains to enhance accuracy of predicting TF DNA binding sites (TFBSs). To address the first question, we developed a novel method using computational representation of proteins based on characteristics of different protein regions (N-terminal, M-region and C-terminal) and combined these with the properties of protein aa sequences. We show that this description provides important biological insight about characterization of the protein functional groups. Using feature selection techniques, we identified key properties of proteins that allow for very accurate characterization of different protein families. We demonstrated efficiency of our method in application to a number of antimicrobial peptide families. To address the second question we developed another novel method that uses a combination of aa properties of DNA binding domains of TFs and their TFBS properties to develop machine learning models for predicting TFBSs. Feature selection is used to identify the most relevant characteristics

  1. Synthesis, Optical Properties and Applications for New Trianguleniums Derivatives

    DEFF Research Database (Denmark)

    Santella, Marco

    The development of new types of emissive organic dyes is an exciting area of research due to the applicability of these compounds in a wide range of disciplines. Cationic triangulenium salts are highly stable carbenium ions with a planar conformation. The convenient and versatile synthetic proced...... focused on the synthesis of thioether para substituted dyes, where the reactivity of various para-methoxy substituted propeller shaped cations towards different alkyl thiols was examined. Furthermore, ringclosure reactions of these thioether bearing propellers in order to obtain trioxa...... structures. These dyes possess excellent emissive properties with possible applications as cell staining agents or as fluorescent probes. Lastly, I focused on the use of triangulenes as binding group for molecular electronics. It has been shown that TATA can form self-assembled monolayers (SAMs) on a gold...

  2. Properties and medical applications of shape memory alloys.

    Science.gov (United States)

    Tarniţă, Daniela; Tarniţă, D N; Bîzdoacă, N; Mîndrilă, I; Vasilescu, Mirela

    2009-01-01

    One of the most known intelligent material is nitinol, which offers many functional advantages over conventional implantable alloys. Applications of SMA to the biomedical field have been successful because of their functional qualities, enhancing both the possibility and the execution of less invasive surgeries. The biocompatibility of these alloys is one of their most important features. Different applications exploit the shape memory effect (one-way or two-way) and the super elasticity, so that they can be employed in orthopedic and cardiovascular applications, as well as in the manufacture of new surgical tools. Therefore, one can say that smart materials, especially SMA, are becoming noticeable in the biomedical field. Super elastic NiTi has become a material of strategic importance as it allows to overcome a wide range of technical and design issues relating to the miniaturization of medical devices and the increasing trend for less invasive and therefore less traumatic procedures. This paper will consider just why the main properties of shape memory alloys hold so many opportunities for medical devices and will review a selection of current applications.

  3. Thermoluminescent properties of CVD diamond: applications to ionising radiation dosimetry

    International Nuclear Information System (INIS)

    Petitfils, A.

    2007-09-01

    Remarkable properties of synthetic diamond (human soft tissue equivalence, chemical stability, non-toxicity) make this material suitable for medical application as thermoluminescent dosimeter (TLD). This work highlights the interest of this material as radiotherapy TLD. In the first stage of this work, we looked after thermoluminescent (TL) and dosimetric properties of polycrystalline diamond made by Chemically Vapor Deposited (CVD) synthesis. Dosimetric characteristics are satisfactory as TLD for medical application. Luminescence thermal quenching on diamond has been investigated. This phenomenon leads to a decrease of dosimetric TL peak sensitivity when the heating rate increases. The second part of this work analyses the use of synthetic diamond as TLD in radiotherapy. Dose profiles, depth dose distributions and the cartography of an electron beam obtained with our samples are in very good agreement with results from an ionisation chamber. It is clearly shown that CVD) diamond is of interest to check beams of treatment accelerators. The use of these samples in a control of treatment with Intensity Modulated Radiation Therapy underlines good response of synthetic diamond in high dose gradient areas. These results indicate that CVD diamond is a promising material for radiotherapy dosimetry. (author)

  4. Polymer composites with graphene nanofillers: electrical properties and applications.

    Science.gov (United States)

    Tjong, Sie Chin

    2014-02-01

    Graphene with extraordinary high elastic modulus and excellent electrical conductivity has good prospects for use as the filler material for fabricating novel polymer composites designed for electrostatic discharge and EMI shielding protection, field emission, gas sensor, and fuel cell applications. Large amounts of graphene oxide (GO) can be obtained by wet chemical oxidation of graphite into a mixture of concentrated sulfuric acid, sodium nitrate and potassium permanganate. Accordingly, carbon atoms in the basal plane and edges of GO are decorated with oxygenated functional groups, forming an electrical insulator. To restore electrical conductivity, chemical reduction or thermal annealing is needed to eliminate oxygenated groups of GO. However, such treatments induce internal defects and remove oxygenated atoms of GO partially. The remnant-oxygenated groups affect electrical conductivity of graphene greatly. Nevertheless, reduced graphene oxide and thermally reduced graphene oxide are sufficiently conductive to form polymer nanocomposites at very low percolation threshold. This review provides the fundamentals and state-of-the-art developments in the fabrication methods and electrical property characterizations as well as the applications of novel graphene/polymer nanocomposites. Particular attention is paid to their processing-structural-electrical property relationships.

  5. Cellulosic Bionanocomposites: A Review of Preparation, Properties and Applications

    Directory of Open Access Journals (Sweden)

    Alain Dufresne

    2010-12-01

    Full Text Available Cellulose is the most abundant biomass material in nature. Extracted from natural fibers, its hierarchical and multi-level organization allows different kinds of nanoscaled cellulosic fillers—called cellulose nanocrystals or microfibrillated cellulose (MFC—to be obtained. Recently, such cellulose nanoparticles have been the focus of an exponentially increasing number of works or reviews devoted to understanding such materials and their applications. Major studies over the last decades have shown that cellulose nanoparticles could be used as fillers to improve mechanical and barrier properties of biocomposites. Their use for industrial packaging is being investigated, with continuous studies to find innovative solutions for efficient and sustainable systems. Processing is more and more important and different systems are detailed in this paper depending on the polymer solubility, i.e., (i hydrosoluble systems, (ii non-hydrosoluble systems, and (iii emulsion systems. This paper intends to give a clear overview of cellulose nanoparticles reinforced composites with more than 150 references by describing their preparation, characterization, properties and applications.

  6. Thin film separators with ion transport properties for energy applications

    Science.gov (United States)

    Li, Zhongyuan

    2017-09-01

    Recent years, along with the increasing need of energy, energy storage also becomes a challenging problem which we need to deal with. The batterieshave a good developing prospect among energy storage system in storing energy such as wind, solar and geothermal energy. One hurdle between the lab-scale experiment and industry-scale application of the advanced batteries is the urgent need for limiting charging capacity degradation and improving cycling stability, known as the shuttle effect in lithium-sulfur batteries or electroosmotic drag coefficient in fuel-cell batteries. The microporous separator between the cathode and anode could be molecular engineered to possessesion selective permeation properties, which can greatly improves the energy efficiency and extends application range of the battery. The present review offers the fundamental fabrication methods of separator film with different material. The review also contains the chemical or physical structure of different materials which are used in making separator film. A table offers the reader a summary of properties such as ionic conductivity, ionic exchange capacity and current density etc.

  7. Thermophysical Modeling of Contact Binary Near-Earth Asteroid 1996 HW1

    NARCIS (Netherlands)

    Magri, C.; Howell, E. S.; Nolan, M. C.; Taylor, P. A.; Fernández, Y. R.; Mueller, M.; Rivkin, A. S.; Vervack, R. J., Jr.

    2011-01-01

    Near-Earth asteroid (8567) 1996 HW1 was observed spectroscopically at 1.9-4.0 microns during August- October 2008 using the SpeX instrument at NASA's Infrared Telescope Facility (IRTF). These spectra are being modeled using a new thermophysical program that accounts for the object's spin orientation

  8. Optical Properties and Immunoassay Applications of Noble Metal Nanoparticles

    Directory of Open Access Journals (Sweden)

    Shaoli Zhu

    2010-01-01

    Full Text Available Noble metal, especially gold (Au and silver (Ag nanoparticles exhibit unique and tunable optical properties on account of their surface plasmon resonance (SPR. In this paper, we mainly discussed the theory background of the enhanced optical properties of noble metal nanoparticles. Mie theory, transfer matrix method, discrete dipole approximation (DDA method, and finite-difference time domain (FDTD method applied brute-force computational methods for different nanoparticles optical properties. Some important nanostructure fabrication technologies such as nanosphere lithography (NSL and focused ion beam (FIB are also introduced in this paper. Moreover, these fabricated nanostructures are used in the plasmonic sensing fields. The binding signal between the antibody and antigen, amyloid-derived diffusible ligands (ADDLs-potential Alzheimer's disease (AD biomarkers, and staphylococcal enterotixn B (SEB in nano-Moore per liter (nM concentration level are detected by our designed nanobiosensor. They have many potential applications in the biosensor, environment protection, food security, and medicine safety for health, and so forth, fields.

  9. Optical Properties and Immunoassay Applications of Noble Metal Nanoparticles

    International Nuclear Information System (INIS)

    Zhu, S.; Zhou, W.

    2010-01-01

    Noble metal, especially gold (Au) and silver (Ag) nanoparticles exhibit unique and tunable optical properties on account of their surface plasmon resonance (SPR). In this paper, we mainly discussed the theory background of the enhanced optical properties of noble metal nanoparticles. Mie theory, transfer matrix method, discrete dipole approximation (DDA) method, and finite-difference time domain (FDTD) method applied brute-force computational methods for different nanoparticles optical properties. Some important nanostructure fabrication technologies such as nanosphere lithography (NSL) and focused ion beam (FIB) are also introduced in this paper. Moreover, these fabricated nanostructures are used in the plasmonic sensing fields. The binding signal between the antibody and antigen, amyloid-derived diffusible ligands (ADDLs)-potential Alzheimer's disease (AD) biomarkers, and staphylococcal enterotoxin B (SEB) in nano-Moore per liter (nM) concentration level are detected by our designed nanobiosensor. They have many potential applications in the biosensor, environment protection, food security, and medicine safety for health, and so forth, fields.

  10. Bismuth Silver Oxysulfide for Photoconversion Applications: Structural and Optoelectronic Properties

    KAUST Repository

    Baqais, Amal Ali Abdulallh

    2017-09-18

    Single-phase bismuth silver oxysulfide, BiAgOS, was prepared by a hydrothermal method. Its structural, morphological and optoelectronic properties were investigated and compared with bismuth copper oxysulfide (BiCuOS). Rietveld refinement of the powder X-ray diffraction (XRD) measurements revealed that the BiAgOS and BiCuOS crystals have the same structure as ZrSiCuAs: the tetragonal space group P4/nmm. X-ray photoelectron spectroscopy (XPS) analyses confirmed that the BiAgOS has a high purity, in contrast with BiCuOS, which tends to have Cu vacancies. The Ag has a monovalent oxidation state, whereas Cu is present in the oxidation states of +1 and +2 in the BiCuOS system. Combined with experimental measurements, density functional theory calculations employing the range-separated hybrid HSE06 exchange-correlation functional with spin-orbit coupling quantitatively elucidated photophysical properties such as ab-sorption coefficients, effective masses and dielectric constants. BiCuOS and BiAgOS were found to have indirect bandgaps of 1.1 and 1.5 eV, respectively. Both possess high dielectric constants and low electron and hole effective masses. Therefore, these materials are expected to have high exciton dissociation capabilities and excellent carrier diffusion properties. This study reveals that BiAgOS is a promising candidate for photoconversion applications.

  11. Thermal infrared observations and thermophysical characterization of the OSIRIS-REx target asteroid (101955) Bennu

    Science.gov (United States)

    Emery, J.; Fernandez, Y.; Kelley, M.; Warden, K.; Hergenrother, C.; Lauretta, D.; Drake, M.; Campins, H.; Ziffer, J.

    2014-07-01

    analysis is inconclusive in terms of surface mineralogy; the emissivity spectra have a relatively low signal-to-noise ratio and no spectral features are detected. The thermal inertia indicates average regolith grain size on the scale of several millimeters to about a centimeter. This moderate grain size is also consistent with low spectral contrast in the 7.5-20 μ m spectral range. If real, the rotational variation in thermal inertia would be consistent with a change in average grain size of only about a millimeter. The thermophysical properties of Bennu's surface appear to be fairly homogeneous longitudinally. A search for a dust coma failed to detect any extended emission, putting an upper limit of about 10^6 g of dust within 4750 km of Bennu. We predict that the OSIRIS-REx spacecraft will find a low-albedo surface with abundant sub-cm sized grains, fairly evenly distributed in longitude.

  12. Thermal infrared observations and thermophysical characterization of OSIRIS-REx target asteroid (101955) Bennu

    Science.gov (United States)

    Emery, J. P.; Fernández, Y. R.; Kelley, M. S. P.; Warden, K. T.; Hergenrother, C.; Lauretta, D. S.; Drake, M. J.; Campins, H.; Ziffer, J.

    2014-05-01

    /2, which is significantly lower than several other NEAs of comparable size. There may be a small variation of thermal inertia with rotational phase (±60 J m-2 K-1 s-1/2). The spectral analysis is inconclusive in terms of surface mineralogy; the emissivity spectra have a relatively low signal-to-noise ratio and no spectral features are detected. The thermal inertia indicates average regolith grain size on the scale of several millimeters to about a centimeter. This moderate grain size is also consistent with low spectral contrast in the 7.5-20 μm spectral range. If real, the rotational variation in thermal inertia would be consistent with a change in average grain size of only about a millimeter. The thermophysical properties of Bennu’s surface appear to be fairly homogeneous longitudinally. A search for a dust coma failed to detect any extended emission, putting an upper limit of about 106 g of dust within 4750 km of Bennu. Three common methodologies for thermal modeling are compared, and some issues to be aware of when interpreting the results of such models are discussed. We predict that the OSIRIS-REx spacecraft will find a low albedo surface with abundant sub-cm sized grains, fairly evenly distributed in longitude.

  13. Molecular simulation: a tool for the industry. Applications to CO{sub 2} capture and storage operations;La simulation moleculaire: un outil au service de l'industrie. Application aux operations de captage et de stockage du CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Lachet, V. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France)

    2010-04-15

    The use of molecular simulation for the calculation of equilibrium and transport properties is a field in constant development, both from a fundamental and an applied point of view. The purpose of this article is to provide the reader with a brief survey of the possible uses of these simulation techniques through the presentation of a few applications in the field of carbon dioxide capture and storage operations. The different examples proposed here show how molecular simulation allows reliable predictions of thermophysical properties of CO{sub 2} or CO{sub 2} bearing mixtures, providing an intermediate way between experiments and classical thermodynamic models. (author)

  14. Silver Nanoparticles: Synthesis, Characterization, Properties, Applications, and Therapeutic Approaches

    Directory of Open Access Journals (Sweden)

    Xi-Feng Zhang

    2016-09-01

    Full Text Available Recent advances in nanoscience and nanotechnology radically changed the way we diagnose, treat, and prevent various diseases in all aspects of human life. Silver nanoparticles (AgNPs are one of the most vital and fascinating nanomaterials among several metallic nanoparticles that are involved in biomedical applications. AgNPs play an important role in nanoscience and nanotechnology, particularly in nanomedicine. Although several noble metals have been used for various purposes, AgNPs have been focused on potential applications in cancer diagnosis and therapy. In this review, we discuss the synthesis of AgNPs using physical, chemical, and biological methods. We also discuss the properties of AgNPs and methods for their characterization. More importantly, we extensively discuss the multifunctional bio-applications of AgNPs; for example, as antibacterial, antifungal, antiviral, anti-inflammatory, anti-angiogenic, and anti-cancer agents, and the mechanism of the anti-cancer activity of AgNPs. In addition, we discuss therapeutic approaches and challenges for cancer therapy using AgNPs. Finally, we conclude by discussing the future perspective of AgNPs.

  15. Silver Nanoparticles: Synthesis, Characterization, Properties, Applications, and Therapeutic Approaches

    Science.gov (United States)

    Zhang, Xi-Feng; Liu, Zhi-Guo; Shen, Wei; Gurunathan, Sangiliyandi

    2016-01-01

    Recent advances in nanoscience and nanotechnology radically changed the way we diagnose, treat, and prevent various diseases in all aspects of human life. Silver nanoparticles (AgNPs) are one of the most vital and fascinating nanomaterials among several metallic nanoparticles that are involved in biomedical applications. AgNPs play an important role in nanoscience and nanotechnology, particularly in nanomedicine. Although several noble metals have been used for various purposes, AgNPs have been focused on potential applications in cancer diagnosis and therapy. In this review, we discuss the synthesis of AgNPs using physical, chemical, and biological methods. We also discuss the properties of AgNPs and methods for their characterization. More importantly, we extensively discuss the multifunctional bio-applications of AgNPs; for example, as antibacterial, antifungal, antiviral, anti-inflammatory, anti-angiogenic, and anti-cancer agents, and the mechanism of the anti-cancer activity of AgNPs. In addition, we discuss therapeutic approaches and challenges for cancer therapy using AgNPs. Finally, we conclude by discussing the future perspective of AgNPs. PMID:27649147

  16. Edible films and coatings: Sources, properties and application

    Directory of Open Access Journals (Sweden)

    Šuput Danijela Z.

    2015-01-01

    Full Text Available In order to extend product shelf life while preserving the quality scientific attention focused to biopolymers research that are base for edible films and coatings production. Another major advantage of this kind of food packaging is their eco-friendly status because biopolymers do not cause environmental problems as packaging materials derived from non-renewable energy sources do. Objective of this work was to review recently studied edible films and coatings - their sources, properties and possible application. As sources for edible biopolymers were highlighted polysaccharides, proteins and lipids. The most characteristic subgroups from each large group of compounds were selected and described regarding possible physical and mechanical protection; migration, permeation, and barrier functions. The most important biopolymers characteristic is possibility to act as active substance carriers and to provide controlled release. In order to achieve active packaging functions emulsifiers, antioxidants and antimicrobial agents can also be incorporated into film-forming solutions in order to protect food products from oxidation and microbial spoilage, resulting in quality improvement and enhanced safety. The specific application where edible films and coatings have potential to replace some traditional polymer packaging are explained. It can be concluded that edible films and coatings must be chosen for food packaging purpose according to specific applications, the types of food products, and the major mechanisms of quality deterioration.

  17. Controlling polypropylene rheological properties by promoting organic peroxide during extrusion with improved properties for automotive applications

    Science.gov (United States)

    Herlambang, Bayu; Sandytama

    2017-05-01

    Excellent stability and processability of Controlled-Rheology Polypropylene (CRPP) was mandatory parameters especially for automotive application. Selected organic peroxide which was used to control the rheology of PP should perform good stability in physical properties due to pre-process of compounding for automotive application. The common organic peroxide that widely used is 2,5-dimethyl-2,5-di-tert-butylperoxyhexane (DHBP). However, the problems that usually encountered are Melt Flow Index (MFI) stability, initial color, and the odor which come from decomposition process. Research and Development (RND) team of PT Chandra Asri Petrochemical, Tbk (CAP) did the study to change the type of organic peroxide to 3,6,9-triethyl-3,6,9,-trimethyl-l,4,7-triperoxonane (TETMTPA) which was intended to improve these inferiorities when using DHBP. The results indicate better MFT stability, better initial color, and less odor when using TETMTPA than DHBP. This superiority is very applicable particularly for automotive application. Detailed analysis about volatile decomposition product from both peroxide indicated CRPP with TETMTPA has lower volatile compound which result lower odor level than CRPP with DHBP.

  18. Thermophysical Properties of Selected Aerospace Materials. Part 1. Thermal Radiative Properties

    Science.gov (United States)

    1976-01-01

    4 .4 W «4 .4 .4 O ►- at9 ><T>0>0l^ɘ^o>O«4>0OI\\J|k.9K «eo«O«oic«300a5«f-.r-v0ir\\J-ro.»M eooeooooooaoooooo ii\\in«aiw.«(\\j^n9>e^ɜnirtt>.m...PREPARED BY CATHOOIC AND PLASMA TORCH SPRAYING. BUCH, J. ELEXTPOTECH. CAS. 21, I 3 1. 158-90. 1973. T7iai9 REFLECTION

  19. Thermophysical Properties of Matter - the TPRC Data Series. Volume 14. Master Index - To Materials and Properties

    Science.gov (United States)

    1979-01-01

    2-Butyne, crotonylene - 6s’ 12 - Butyric alcohol - 6s’ 6 - - -- - Butyric ether - 6s~ 37 Cabbage - -- 10 630 - Cadilii~mn, Cd 1’ 45 4, 29 7 91 7...832 71 + Pb43 TI + Sn 11: -3 I - - - - TI + Ta 1i 81e Thallium bromide, TIBr 2’ 570 81778 8 783 131 826 780 782 I ThalIium bromide chloride 8811455 1457... Thallium bromide Iodide 1459 811461 _1463 ThalliYR bromide + thali m chlorIde, 113015 KIRS-6 - - 814S 1457 - - 1301 Tha;I.m bromide + thallium

  20. Thermophysical Properties of Matter - The TPRC Data Series. Volume 9. Thermal Radiative Properties - Coatings

    Science.gov (United States)

    1972-01-01

    Formaldehyde Contact Coatings - Normal Spectral Reflectance • . 1116 621 Butylated Urea Formaldehyde Contact Coatings - Normal Spectral Reflectance...Coatings - formal Solar Absorptance 1127 629* Lacquer Contact Coatings - Normal Spectral Transmittance 1129 530* Melamlne Formaldehyde Contact...OOOOOOOOOOA so ft OOOOOOOOSOOOOOOO <-l H o: St*inoot«ao^|*inQt*»-«t*o - «mO’HNMWoDOcoint- oxo e>5e>3co^’’»’**^’«tininininatot- d d d d d d

  1. Perceived Properties of Parameterised Music for Interactive Applications

    Directory of Open Access Journals (Sweden)

    Jan Berg

    2006-04-01

    Full Text Available Traditional implementations of sound and music in interactive contexts have their limitations. One way to overcome these and to expand the possibilities of music is to handle the music in a parameterised form. To better understand the properties of the musical parameters resulting from parameterisation, two experiments were carried out. The first experiment investigated selected parameters' capability to change the music; the second experiment examined how the parameters can contribute to express emotions. From these experiments, it is concluded that users without musical training perform differently from musicians on some of the parameters. There is also a clear association between the parameters and the expressed basic emotions. The paper is concluded with observations on how parameterisation might be used in interactive applications.

  2. Design, Properties and Recent Application of Macrocycles in Medicinal Chemistry.

    Science.gov (United States)

    Ermert, Philipp

    2017-10-25

    Macrocyclic compounds have recently received increasing attention in drug discovery as these compounds offer the potential to modulate difficult targets and to access novel chemotypes. Approaches towards libraries of macrocyclic compounds based on modular organic synthesis and applications of these technology platforms to find and improve biologically active compounds are introduced in this minireview. Alternatively, lead compounds may be obtained by truncation and modification of macrocyclic natural products. Selected medicinal chemistry programs are discussed, illustrating a macrocyclization approach toward ligands with improved properties. The design of such ligands is often informed by X-ray crystal structures of protein-ligand complexes. Efforts to understand cellular permeability and oral bioavailability of cyclic peptides and non-peptidic macrocycles are summarized.

  3. On Six-Parameter Frechet Distribution: Properties and Applications

    Directory of Open Access Journals (Sweden)

    Haitham M. Yousof

    2016-06-01

    Full Text Available This paper introduces a new generalization of the transmuted Marshall-Olkin Frechet distribution of A…fy et al. (2015, using Kumaraswamy generalized family. The new model is referred to as Kumaraswamy transmuted Marshall-Olkin FrØchet distribution. This model contains sixty two sub-models as special cases such as the Kumaraswamy transmuted Frechet, Kumaraswamy transmuted Marshall-Olkin, generalized inverse Weibull and Kumaraswamy Gumbel type II distributions, among others. Various mathematical properties of the proposed distribution including closed forms for ordinary and incomplete moments, quantile and generating functions and Renyi and -entropies are derived. The unknown parameters of the new distribution are estimated using the maximum likelihood estimation. We illustrate the importance of the new model by means of two applications to real data sets.

  4. Properties and potential optoelectronic applications of lead halide perovskite nanocrystals

    Science.gov (United States)

    Kovalenko, Maksym V.; Protesescu, Loredana; Bodnarchuk, Maryna I.

    2017-11-01

    Semiconducting lead halide perovskites (LHPs) have not only become prominent thin-film absorber materials in photovoltaics but have also proven to be disruptive in the field of colloidal semiconductor nanocrystals (NCs). The most important feature of LHP NCs is their so-called defect-tolerance—the apparently benign nature of structural defects, highly abundant in these compounds, with respect to optical and electronic properties. Here, we review the important differences that exist in the chemistry and physics of LHP NCs as compared with more conventional, tetrahedrally bonded, elemental, and binary semiconductor NCs (such as silicon, germanium, cadmium selenide, gallium arsenide, and indium phosphide). We survey the prospects of LHP NCs for optoelectronic applications such as in television displays, light-emitting devices, and solar cells, emphasizing the practical hurdles that remain to be overcome.

  5. Fabrication, properties, and applications of porous metals with directional pores

    Science.gov (United States)

    NAKAJIMA, Hideo

    2010-01-01

    Lotus-type porous metals with aligned long cylindrical pores are fabricated by unidirectional solidification from the melt with a dissolved gas such as hydrogen, nitrogen, or oxygen. The gas atoms can be dissolved into the melt via a pressurized gas atmosphere or thermal decomposition of gaseous compounds. Three types of solidification techniques have been developed: mold casting, continuous zone melting, and continuous casting techniques. The last method is superior from the viewpoint of mass production of lotus metals. The observed anisotropic behaviors of the mechanical properties, sound absorption, and thermal conductivity are inherent to the anisotropic porous structure. In particular, the remarkable anisotropy in the mechanical strength is attributed to the stress concentration around the pores aligned perpendicular to the loading direction. Heat sinks are a promising application of lotus metals due to the high cooling performance with a large heat transfer. PMID:21084772

  6. Optimised Dirac operators on the lattice. Construction, properties and applications

    Energy Technology Data Exchange (ETDEWEB)

    Bietenholz, W. [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik]|[Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC

    2006-11-15

    We review a number of topics related to block variable renormalisation group transformations of quantum fields on the lattice, and to the emerging perfect lattice actions. We first illustrate this procedure by considering scalar fields. Then we proceed to lattice fermions, where we discuss perfect actions for free fields, for the Gross-Neveu model and for a supersymmetric spin model. We also consider the extension to perfect lattice perturbation theory, in particular regarding the axial anomaly and the quark gluon vertex function. Next we deal with properties and applications of truncated perfect fermions, and their chiral correction by means of the overlap formula. This yields a formulation of lattice fermions, which combines exact chiral symmetry with an optimisation of further essential properties. We summarise simulation results for these so-called overlap-hypercube fermions in the two-flavour Schwinger model and in quenched QCD. In the latter framework we establish a link to Chiral Perturbation Theory, both, in the p-regime and in the epsilon-regime. In particular we present an evaluation of the leading Low Energy Constants of the chiral Lagrangian - the chiral condensate and the pion decay constant - from QCD simulations with extremely light quarks. (orig.)

  7. Optimised Dirac operators on the lattice. Construction, properties and applications

    International Nuclear Information System (INIS)

    Bietenholz, W.; Deutsches Elektronen-Synchrotron

    2006-11-01

    We review a number of topics related to block variable renormalisation group transformations of quantum fields on the lattice, and to the emerging perfect lattice actions. We first illustrate this procedure by considering scalar fields. Then we proceed to lattice fermions, where we discuss perfect actions for free fields, for the Gross-Neveu model and for a supersymmetric spin model. We also consider the extension to perfect lattice perturbation theory, in particular regarding the axial anomaly and the quark gluon vertex function. Next we deal with properties and applications of truncated perfect fermions, and their chiral correction by means of the overlap formula. This yields a formulation of lattice fermions, which combines exact chiral symmetry with an optimisation of further essential properties. We summarise simulation results for these so-called overlap-hypercube fermions in the two-flavour Schwinger model and in quenched QCD. In the latter framework we establish a link to Chiral Perturbation Theory, both, in the p-regime and in the epsilon-regime. In particular we present an evaluation of the leading Low Energy Constants of the chiral Lagrangian - the chiral condensate and the pion decay constant - from QCD simulations with extremely light quarks. (orig.)

  8. Graphene Thermal Properties: Applications in Thermal Management and Energy Storage

    Directory of Open Access Journals (Sweden)

    Jackie D. Renteria

    2014-11-01

    Full Text Available We review the thermal properties of graphene, few-layer graphene and graphene nanoribbons, and discuss practical applications of graphene in thermal management and energy storage. The first part of the review describes the state-of-the-art in the graphene thermal field focusing on recently reported experimental and theoretical data for heat conduction in graphene and graphene nanoribbons. The effects of the sample size, shape, quality, strain distribution, isotope composition, and point-defect concentration are included in the summary. The second part of the review outlines thermal properties of graphene-enhanced phase change materials used in energy storage. It is shown that the use of liquid-phase-exfoliated graphene as filler material in phase change materials is promising for thermal management of high-power-density battery parks. The reported experimental and modeling results indicate that graphene has the potential to outperform metal nanoparticles, carbon nanotubes, and other carbon allotropes as filler in thermal management materials.

  9. Autofluorescence properties of skin and applications in dermatology

    Science.gov (United States)

    Zeng, Haishan; McLean, David I.; MacAulay, Calum E.; Lui, Harvey

    2000-10-01

    Skin autofluorescence was observed as early as 1908. Its applications in dermatology was first reported in 1925- the use of Wood's lamp for the detection of fungal infection. In the first part of the paper, a historical review was presented on skin autofluorescence properties. In the second part, systematic research done in out laboratory on autofluorescence properties of normal and diseased skin was summarized. We developed three tools for the study: 1) a compact fiber optic spectrometer for in vivo macroscopic fluorescence spectral measurements on volunteers and patients; 2) a CCD camera based fluorescence imaging for in vivo macroscopic imaging of 2D fluorescence intensity distributions over various skin diseases; 3) a fiber optic microspectrophotometer (MSP) system for in vitro microscopic fluorescence spectral measurements and fluorescence imaging of frozen tissue sections. With these tools, we obtained the excitation-emission matrices (EEMs) of in vivo normal skin, the temporal dynamics of skin autofluorescence decay under continuous wave laser exposure, and fluorescence spectra of 1500 lesions from 600 patients spanning 35 disease types. Monte Carlo simulation has been employed to explain the autofluorescence decay dynamics and to reconstruct the in vivo spectra from in vitro microscopic fluorophore distribution and intrinsic fluorescence spectra of various skin structures. Spectral feature based linear discrimination function analysis and principal components decomposition analysis are performed to assess the potential of autofluorescence spectroscopy for skin cancer detection. Clinical test of a fluorescence scope system for skin cancer margin delineation is under way.

  10. Evaluations of properties and review applications of some chemical dosimeters

    International Nuclear Information System (INIS)

    Mergani, F. F.

    2010-12-01

    A chemical dosimeter is one of the most important methods used to measure radiation doses via a chemical reaction caused by the ionizing radiation. It is a system that measures the dose rate by chemical changes when it is exposed to ionizing radiation. This interaction produces changes in the chemical properties of the material that used as dosimeter as well as change in color. In all chemical dosimeters radiation induced chemical reaction produces new species, which its properties long lived enough to determine its quantity or the change in the initial system. This study discussed some different types of chemical dosimeters such as aqueous, gaseous and solid, the great consideration was given to aqueous systems because of their vital role in many applications. The dose rate of gamma cell was measured by using Fricke dosimeter found that dose rate about 0.909 Gy/sec while the theoretical dose rate was 0.910 Gy/sec, which confirms the suitability of Fricke dosimeter for this calibration. (Author)

  11. Application Of Geographic Information System In Property Valuation

    Directory of Open Access Journals (Sweden)

    Stephen Wakaba Gatheru

    2015-08-01

    Full Text Available ABSTRACT The purpose of this study was to investigate the application of Geographic Information System GIS in property valuation. The study adopted descriptive research design to investigate the relationship between value of land and the factors influencing it. A population of 400 land parcels was used with a sample size of 100 parcels of land. Data collection was done by use of questionnaires. A multivariate regression model was used to link the independent variables to the dependent variable. The resultant Hedonic Pricing Model HPM indicated that the value of land can be predicted by using the following key attributes land size accessibility to bypass accessibility to primary school. Results also showed that Hedonic Pricing Model is objective and verifiable and hence an ideal method of valuation.GIS technique has proved to be a powerful tool in ensuring that a geodatabase of all the attributes of each parcel of land is stored and retrievable at the clique of a button. The valuation map that was produced enables quick decision making as all the values of each parcel are displayed graphically. It is recommended that the HRM and GIS be used to do property valuation.

  12. Optimised Dirac operators on the lattice: construction, properties and applications

    Energy Technology Data Exchange (ETDEWEB)

    Bietenholz, Wolfgang [Humbolt-Universitaet zu Berlin (Germany). Inst. fuer Physik; Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing (NIC)

    2006-12-15

    We review a number of topics related to block variable renormalisation group transformations of quantum fields on the lattice, and to the emerging perfect lattice actions. We first illustrate this procedure by considering scalar fields. Then we proceed to lattice fermions, where we discuss perfect actions for free fields, for the Gross-Neveu model and for a supersymmetric spin model. We also consider the extension to perfect lattice perturbation theory, in particular regarding the axial anomaly and the quark gluon vertex function. Next we deal with properties and applications of truncated perfect fermions, and their chiral correction by means of the overlap formula. This yields a formulation of lattice fermions, which combines exact chiral symmetry with an optimisation of further essential properties. We summarise simulation results for these so-called overlap-hypercube fermions in the two-flavour Schwinger model and in quenched QCD. In the latter framework we establish a link to Chiral Perturbation Theory, both, in the p-regime and in the e-regime. In particular we present an evaluation of the leading Low Energy Constants of the chiral Lagrangian - the chiral condensate and the pion decay constant - from QCD simulations with extremely light quarks. (author)

  13. Properties of super stainless steels for orthodontic applications.

    Science.gov (United States)

    Oh, Keun-Taek; Kim, Young-Sik; Park, Yong-Soo; Kim, Kyoung-Nam

    2004-05-15

    Orthodontic stainless-steel appliances are considered to be corrosion resistant, but localized corrosion can occur in the oral cavity. This study was undertaken to evaluate the properties of super stainless steels in orthodontic applications. Accordingly, the metallurgical properties, mechanical properties, corrosion resistance, amount of the released nickel, cytotoxicity, and characteristics of the passive film were investigated. Corrosion resistances of the specimens were high and in the following order: super austenitic stainless steel (SR-50A) > super ferritic stainless steel (SFSS) = super duplex stainless steel (SR-6DX) > 316L SS > super martensitic stainless steel (SR-3Mo) in artificial saliva, 37 degrees C. At 500 mV (SCE), current densities of SR-50A, SFSS, SR-6DX, 316L SS, and SR-3Mo were 5.96 microA/cm(2), 20.3 microA/cm(2), 31.9 microA/cm(2), 805 microA/cm(2), and 5.36 mA/cm(2), respectively. Open circuit potentials of SR-50A, 316L SS, SR-6DX, SR-3Mo, and SFSS were - 0.2, - 0.22, - 0.24, - 0.43, and - 0.46 V (SCE), respectively. SR-50A, SFSS, and SR-6DX released below 3 ng/ml nickel for 8 weeks, and increased a little with immersion time, and 316L SS released about 3.5 ng/ml nickel, but SR-3Mo released a large amount of nickel, which increased with immersion time. The study demonstrated that SR-50A, SR-6DX, and SFSS have high corrosion resistance and mild or no cytotoxicity, due to the passive film enhanced by synergistic effect of Mo + N or by high addition effect of Cr + W. All super stainless steels showed very low cytotoxicity regardless of their nickel contents, although SR-3Mo was found to be relatively cytotoxic. From these studies, these steels are considered suitable for orthodontic applications. Copyright 2004 Wiley Periodicals, Inc.

  14. Silicon photomultipliers. Properties and applications in a highly granular calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Feege, Nils

    2008-12-15

    Silicon Photomultipliers (SiPMs) are novel semiconductor-based photodetectors operated in Geiger mode. Their response is not linear, and both their gain and their photon detection efficiency depend on the applied bias voltage and on temperature. The CALICE collaboration investigates several technology options for highly granular calorimeters for the future ILC. The prototype of a scintillator-steel sampling calorimeter with analogue readout for hadrons constructed at DESY and successfully operated in testbeam experiments at DESY, CERN and FNAL by this collaboration is the first large scale application for 7608 SiPMs developed by MEPhI. This thesis deals with properties of the SiPMs used in the calorimeter prototype. The effective numer of pixels of the SiPMs, which influences their saturation behaviour, is extracted from in situ measurements and compared to results obtained for the bare SiPMs. In addition, the effects of temperature and voltage changes on the parameters necessary for the calibration of the SiPMs and the detector are determined. Methods which allow for correcting or compensating these effects are evaluated. An approach to improve the absolute calibration of the temperature sensors in the prototype is described and temperature profiles are studied. Finally, a procedure to adjust the light yield of the cells of the prototype is presented. The results of the application of this procedure during the commissioning of the detector at FNAL are discussed. (orig.)

  15. Chitinases from Bacteria to Human: Properties, Applications, and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Abhishek Singh Rathore

    2015-01-01

    Full Text Available Chitin is the second most plenteous polysaccharide in nature after cellulose, present in cell walls of several fungi, exoskeletons of insects, and crustacean shells. Chitin does not accumulate in the environment due to presence of bacterial chitinases, despite its abundance. These enzymes are able to degrade chitin present in the cell walls of fungi as well as the exoskeletons of insect. They have shown being the potential agents for biological control of the plant diseases caused by various pathogenic fungi and insect pests and thus can be used as an alternative to chemical pesticides. There has been steady increase in demand of chitin derivatives, obtained by action of chitinases on chitin polymer for various industrial, clinical, and pharmaceutical purposes. Hence, this review focuses on properties and applications of chitinases starting from bacteria, followed by fungi, insects, plants, and vertebrates. Designing of chitinase by applying directed laboratory evolution and rational approaches for improved catalytic activity for cost-effective field applications has also been explored.

  16. Defect-related luminescent materials: synthesis, emission properties and applications.

    Science.gov (United States)

    Zhang, Cuimiao; Lin, Jun

    2012-12-07

    Luminescent materials have found a wide variety of applications, including information displays, lighting, X-ray intensification and scintillation, and so on. Therefore, much effort has been devoted to exploring novel luminescent materials so far. In the past decade, defect-related luminescent materials have inspired intensive research efforts in their own right. This kind of luminescent material can be basically classified into silica-based materials, phosphate systems, metal oxides, BCNO phosphors, and carbon-based materials. These materials combine several favourable attributes of traditional commercially available phosphors, which are stable, efficient, and less toxic, being free of the burdens of intrinsic toxicity or elemental scarcity and the need for stringent, intricate, tedious, costly, or inefficient preparation steps. Defect-related luminescent materials can be produced inexpensively and on a large scale by many approaches, such as sol-gel process, hydro(solvo)thermal reaction, hydrolysis methods, and electrochemical methods. This review article highlights the recent advances in the chemical synthesis and luminescent properties of the defect-related materials, together with their control and tuning, and emission mechanisms (solid state physics). We also speculate on their future and discuss potential developments for their applications in lighting and biomedical fields.

  17. Optical and Transport Properties of Organic Molecules: Methods and Applications

    Science.gov (United States)

    Strubbe, David Alan

    Organic molecules are versatile and tunable building blocks for technology, in nanoscale and bulk devices. In this dissertation, I will consider some important applications for organic molecules involving optical and transport properties, and develop methods and software appropriate for theoretical calculations of these properties. Specifically, we will consider second-harmonic generation, a nonlinear optical process; photoisomerization, in which absorption of light leads to mechanical motion; charge transport in junctions formed of single molecules; and optical excitations in pentacene, an organic semiconductor with applications in photovoltaics, optoelectronics, and flexible electronics. In the Introduction (Chapter 1), I will give an overview of some phenomenology about organic molecules and these application areas, and discuss the basics of the theoretical methodology I will use: density-functional theory (DFT), time-dependent density-functional theory (TDDFT), and many-body perturbation theory based on the GW approximation. In the subsequent chapters, I will further discuss, develop, and apply this methodology. 2. I will give a pedagogical derivation of the methods for calculating response properties in TDDFT, with particular focus on the Sternheimer equation, as will be used in subsequent chapters. I will review the many different response properties that can be calculated (dynamic and static) and the appropriate perturbations used to calculate them. 3. Standard techniques for calculating response use either integer occupations (as appropriate for a system with an energy gap) or fractional occupations due to a smearing function, used to improve convergence for metallic systems. I will present a generalization which can be used to compute response for a system with arbitrary fractional occupations. 4. Chloroform (CHCl3) is a small molecule commonly used as a solvent in measurements of nonlinear optics. I computed its hyperpolarizability for second

  18. Superior heat transfer fluids for solar heating and cooling applications. Final report, 21 August 1978-31 December 1979. Report MRC-DA-953

    Energy Technology Data Exchange (ETDEWEB)

    Parts, L; Miller, D R; Leffingwell, J W; Thompson, Q E

    1980-09-01

    The major objective of this program was the identification of superior, currently available organic heat transfer fluids for solar collector applications. Organic fluids used in the form of aqueous solutions were also to be identified. The required design and handling properties of the fluids were determined through a survey in which 115 designers and manufacturers of solar collectors and collection systems participated. A state-of-the-art survey of commercially available organic heat transfer fluids provided information on fifty fluids. These were grouped into nine classes. This report contains information on limiting, design, and handling properties of these fluids. The limiting properties affix the use temperature ranges of the fluids. The design properties include the following thermophysical data: densities, vapor pressures, viscosities, specific heats, thermal conductivities, heats of vaporization, and coefficients of thermal expansion. The handling properties include: compatibility and incompatibility, with construction materials, chemical sensitivity, ignitability, physiological effects, and biodegradability characteristics. Mutagenicity tests with Salmonella typhimurium bacteria, and ignitability tests were conducted with a number of fluids in this program. The properties of the fluids were analyzed with reference to the required design and handling properties established in the survey of collector manufacturers. Guidelines are provided for the selection of superior fluids to meet specific collector operational and compatibility requirements. These guidelines include the use of heat transfer efficiency factors, that were calculated or the temperature ranges for which thermophysical data were available.

  19. Synthesis, thermal properties and applications of polymer-clay nanocomposites

    International Nuclear Information System (INIS)

    Meneghetti, Paulo; Qutubuddin, Syed

    2006-01-01

    Polymer-clay nanocomposites constitute a new class of materials in which the polymer matrix is reinforced by uniformly dispersed inorganic particles (usually 10 wt.% or less) having at least one dimension in the nanometer scale. Nanocomposites exhibit improved properties when compared to pure polymer or conventional composites, such as enhanced mechanical and thermal properties, reduced gas permeability, and improved chemical stability. In this work, the synthesis of poly(methyl methacrylate) (PMMA)/clay nanocomposites is described via two methods: in situ and emulsion polymerization. The in situ technique follows a two-step process: ion-exchange of the clay to make it hydrophobic, and polymerization after dispersing the functionalized clay in the monomer. The emulsion technique combines the two steps of the in situ method into one by conducting ion-exchange and polymerization in an aqueous medium in the same reactor. The clay (montmorillonite, MMT) is functionalized with a zwitterionic surfactant, octadecyl-dimethyl betaine (C18DMB). Partially exfoliated nanocomposite, observed by transmission electron microscopy (TEM), was obtained by emulsion polymerization with 10 wt.% clay. Glass transition temperature (T g ) of this nanocomposite was 18 deg. C higher than pure PMMA. With the same clay content, in situ polymerization produced intercalated nanocomposite with T g 10 deg. C lower than the emulsion nanocomposite. The storage modulus of partially exfoliated nanocomposite was superior to the intercalated structure and to the pure polymer. Using nanocomposite technology, novel PMMA nanocomposite gel electrolytes were synthesized exhibiting improved ionic conductivity and stable lithium interfacial resistance. Nanocomposites can also be used for gas storage and packaging applications as demonstrated by high barrier polymer-clay films

  20. Characterization of physicochemical properties of ivy nanoparticles for cosmetic application.

    Science.gov (United States)

    Huang, Yujian; Lenaghan, Scott C; Xia, Lijin; Burris, Jason N; Stewart, C Neal; Zhang, Mingjun

    2013-02-01

    Naturally occurring nanoparticles isolated from English ivy (Hedera helix) have previously been proposed as an alternative to metallic nanoparticles as sunscreen fillers due to their effective UV extinction property, low toxicity and potential biodegradability. This study focused on analyzing the physicochemical properties of the ivy nanoparticles, specifically, those parameters which are crucial for use as sunscreen fillers, such as pH, temperature, and UV irradiation. The visual transparency and cytotoxicity of ivy nanoparticles were also investigated comparing them with other metal oxide nanoparticles. Results from this study demonstrated that, after treatment at 100°C, there was a clear increase in the UV extinction spectra of the ivy nanoparticles caused by the partial decomposition. In addition, the UVA extinction spectra of the ivy nanoparticles gradually reduced slightly with the decrease of pH values in solvents. Prolonged UV irradiation indicated that the influence of UV light on the stability of the ivy nanoparticle was limited and time-independent. Compared to TiO2 and ZnO nanoparticles, ivy nanoparticles showed better visual transparency. Methylthiazol tetrazolium assay demonstrated that ivy nanoparticles exhibited lower cytotoxicity than the other two types of nanoparticles. Results also suggested that protein played an important role in modulating the three-dimensional structure of the ivy nanoparticles. Based on the results from this study it can be concluded that the ivy nanoparticles are able to maintain their UV protective capability at wide range of temperature and pH values, further demonstrating their potential as an alternative to replace currently available metal oxide nanoparticles in sunscreen applications.

  1. Adsorption Properties and Potential Applications of Bamboo Charcoal: A Review

    OpenAIRE

    Isa S.S.M.; Ramli M.M.; Hambali N.A.M.A.; Kasjoo S.R.; Isa M.M.; Nor N.I.M.; Khalid N.; Ahmad N.

    2016-01-01

    Bamboo charcoal was produced by pyrolysis or carbonization process with extraordinary properties such as high conductivity, large surface area and adsorption property. These properties can be improved by activation process that can be done thermally or chemically. In this paper, carbonization and activation process of bamboo, its structural and adsorption properties will be presented. Herein, the adsorption properties of bamboo charcoal that has fully utilized in solar cell as the electrode, ...

  2. Plasmonic doped semiconductor nanocrystals: Properties, fabrication, applications and perspectives

    Science.gov (United States)

    Kriegel, Ilka; Scotognella, Francesco; Manna, Liberato

    2017-02-01

    semiconductor NCs with LSPRs covering the entire spectral range, from the mid- to the NIR. We focus on copper chalcogenide NCs and impurity doped metal oxide NCs as the most investigated alternatives to noble metals. We shed light on the structural changes upon LSPR tuning in vacancy doped copper chalcogenide NCs and deliver a picture for the fundamentally different mechanism of LSPR modification of impurity doped metal oxide NCs. We review on the peculiar optical properties of plasmonic degenerately doped NCs by highlighting the variety of different optical measurements and optical modeling approaches. These findings are merged in an exhaustive section on new and exciting applications based on the special characteristics that plasmonic semiconductor NCs bring along.

  3. Catalytic properties and biomedical applications of cerium oxide nanoparticles

    KAUST Repository

    Walkey, Carl D.

    2014-11-10

    Cerium oxide nanoparticles (nanoceria) have shown promise as catalytic antioxidants in the test tube, cell culture models and animal models of disease. However given the reactivity that is well established at the surface of these nanoparticles, the biological utilization of nanoceria as a therapeutic still poses many challenges. Moreover the form that these particles take in a biological environment, such as the changes that can occur due to a protein corona, are not well established. This review aims to summarize the existing literature on biological use of nanoceria, and to raise questions about what further study is needed to apply this interesting catalytic material to biomedical applications. These questions include: 1) How does preparation, exposure dose, route and experimental model influence the reported effects of nanoceria in animal studies? 2) What are the considerations to develop nanoceria as a therapeutic agent in regards to these parameters? 3) What biological targets of reactive oxygen species (ROS) and reactive nitrogen species (RNS) are relevant to this targeting, and how do these properties also influence the safety of these nanomaterials?

  4. Silver nanoparticles: synthesis, properties, toxicology, applications and perspectives

    Science.gov (United States)

    Tran, Quang Huy; Quy Nguyen, Van; Le, Anh-Tuan

    2013-09-01

    In recent years the outbreak of re-emerging and emerging infectious diseases has been a significant burden on global economies and public health. The growth of population and urbanization along with poor water supply and environmental hygiene are the main reasons for the increase in outbreak of infectious pathogens. Transmission of infectious pathogens to the community has caused outbreaks of diseases such as influenza (A/H5N1), diarrhea (Escherichia coli), cholera (Vibrio cholera), etc throughout the world. The comprehensive treatments of environments containing infectious pathogens using advanced disinfectant nanomaterials have been proposed for prevention of the outbreaks. Among these nanomaterials, silver nanoparticles (Ag-NPs) with unique properties of high antimicrobial activity have attracted much interest from scientists and technologists to develop nanosilver-based disinfectant products. This article aims to review the synthesis routes and antimicrobial effects of Ag-NPs against various pathogens including bacteria, fungi and virus. Toxicology considerations of Ag-NPs to humans and ecology are discussed in detail. Some current applications of Ag-NPs in water-, air- and surface- disinfection are described. Finally, future prospects of Ag-NPs for treatment and prevention of currently emerging infections are discussed.

  5. Optical properties and sensing applications of stellated and bimetallic nanoparticles

    Science.gov (United States)

    Smith, Alison F.

    This dissertation focuses on developing guidelines to aid in the design of new bimetallic platforms for sensing applications. Stellated metal nanostructures are a class of plasmonic colloids in which large electric field enhancements can occur at sharp features, making them excellent candidates for surface enhanced Raman spectroscopy (SERS) and surface enhanced infrared spectroscopy (SE-IRS) platforms. Shape-dependent rules for convex polyhedra such as cubes or octahedra exist, which describe far-field scattering and near-field enhancements. However, such rules are lacking for their concave (stellated) counterparts. This dissertation presents the optical response of stellated Au nanocrystals with Oh, D4h, D3h, C2v, and T d symmetry, which were modeled to systematically investigate the role of symmetry, branching, and particle orientation with respect to excitation source using finite difference time domain (FDTD) calculations. Expanding on stellated nanostructures, bimetallic compositions introduce an interplay between overall architecture and composition to provide tunable optical properties and the potential of new functionality. However, decoupling the complex compositional and structural contributions to the localized surface plasmon resonance (LSPR) remains a challenge, especially when the monometallic counterparts are not synthetically accessible for comparison and the theoretical tools for capturing gradient compositions are lacking. This dissertation explores a stellated Au-Pd nanocrystal model system with Oh symmetry to decouple structural and complex compositional effects on LSPR. (Abstract shortened by ProQuest.).

  6. Application of MD Simulations to Predict Membrane Properties of MOFs

    Directory of Open Access Journals (Sweden)

    Elda Adatoz

    2015-01-01

    Full Text Available Metal organic frameworks (MOFs are a new group of nanomaterials that have been widely examined for various chemical applications. Gas separation using MOF membranes has become an increasingly important research field in the last years. Several experimental studies have shown that thin-film MOF membranes can outperform well known polymer and zeolite membranes due to their higher gas permeances and selectivities. Given the very large number of available MOF materials, it is impractical to fabricate and test the performance of every single MOF membrane using purely experimental techniques. In this study, we used molecular simulations, Monte Carlo and Molecular Dynamics, to estimate both single-gas and mixture permeances of MOF membranes. Predictions of molecular simulations were compared with the experimental gas permeance data of MOF membranes in order to validate the accuracy of our computational approach. Results show that computational methodology that we described in this work can be used to accurately estimate membrane properties of MOFs prior to extensive experimental efforts.

  7. Silver nanoparticles: synthesis, properties, toxicology, applications and perspectives

    International Nuclear Information System (INIS)

    Tran, Quang Huy; Nguyen, Van Quy; Le, Anh-Tuan

    2013-01-01

    In recent years the outbreak of re-emerging and emerging infectious diseases has been a significant burden on global economies and public health. The growth of population and urbanization along with poor water supply and environmental hygiene are the main reasons for the increase in outbreak of infectious pathogens. Transmission of infectious pathogens to the community has caused outbreaks of diseases such as influenza (A/H 5 N 1 ), diarrhea (Escherichia coli), cholera (Vibrio cholera), etc throughout the world. The comprehensive treatments of environments containing infectious pathogens using advanced disinfectant nanomaterials have been proposed for prevention of the outbreaks. Among these nanomaterials, silver nanoparticles (Ag-NPs) with unique properties of high antimicrobial activity have attracted much interest from scientists and technologists to develop nanosilver-based disinfectant products. This article aims to review the synthesis routes and antimicrobial effects of Ag-NPs against various pathogens including bacteria, fungi and virus. Toxicology considerations of Ag-NPs to humans and ecology are discussed in detail. Some current applications of Ag-NPs in water-, air- and surface- disinfection are described. Finally, future prospects of Ag-NPs for treatment and prevention of currently emerging infections are discussed. (review)

  8. Properties of titanium-alloyed DLC layers for medical applications

    Science.gov (United States)

    Joska, Ludek; Fojt, Jaroslav; Cvrcek, Ladislav; Brezina, Vitezslav

    2014-01-01

    DLC-type layers offer a good potential for application in medicine, due to their excellent tribological properties, chemical resistance, and bio-inert character. The presented study has verified the possibility of alloying DLC layers with titanium, with coatings containing three levels of titanium concentration prepared. Titanium was present on the surface mainly in the form of oxides. Its increasing concentration led to increased presence of titanium carbide as well. The behavior of the studied systems was stable during exposure in a physiological saline solution. Electrochemical impedance spectra practically did not change with time. Alloying, however, changed the electrochemical behavior of coated systems in a significant way: from inert surface mediating only exchange reactions of the environment in the case of unalloyed DLC layers to a response corresponding rather to a passive surface in the case of alloyed specimens. The effect of DLC layers alloying with titanium was tested by the interaction with a simulated body fluid, during which precipitation of a compound containing calcium and phosphorus - basic components of the bone apatite - occurred on all doped specimens, in contrast to pure DLC. The results of the specimens' surface colonization with cells test proved the positive effect of titanium in the case of specimens with a medium and highest content of this element. PMID:25093457

  9. Pediocins: The bacteriocins of Pediococci. Sources, production, properties and applications

    Directory of Open Access Journals (Sweden)

    Anastasiadou Sofia

    2009-01-01

    Full Text Available Abstract Class IIa bacteriocins from lactic acid bacteria are small, cationic proteins with antilisterial activity. Within this class, the pediocins are those bacteriocins that share a highly conserved hydrophilic and charged N-terminal part harboring the consensus sequence -YGNGV- and a more variable hydrophobic and/or amphiphilic C-terminal part. Several pediocins have been isolated and characterized. Despite the structural similarities, their molecular weight varies, as well as their spectrum of antimicrobial activity. They exhibit important technological properties, e.g. thermostability and retaining of activity at a wide pH range, which along with the bactericidal action against Gram-positive food spoilage and pathogenic bacteria, make them an important class of biopreservatives. Much new information regarding the pediocins has emerged during the last years. In this review, we summarize and discuss all the available information regarding the sources of pediocins, the characteristics of their biosynthesis and production in fermentation systems, the characteristics of the known pediocin molecules, and their antibacterial action. The advances made by genetic engineering in improving the features of pediocins are also discussed, as well as their perspectives for future applications.

  10. Mechanism of photonic band gap, optical properties, tuning and applications

    International Nuclear Information System (INIS)

    Tiwari, A.; Johri, M.

    2006-05-01

    Mechanism of occurrence of Photonic Band Gap (PBG) is presented for 3-D structure using close packed face centered cubic lattice. Concepts and our work, specifically optical properties of 3-D photonic crystal, relative width, filling fraction, effective refractive index, alternative mechanism of photonic band gap scattering strength and dielectric contrast, effect of fluctuations and minimum refractive index contrast, are reported. The temperature tuning and anisotropy of nematic and ferroelectric liquid crystal infiltrated opal for different phase transitions are given. Effective dielectric constant with filling fraction using Maxwell Garnet theory (MG), multiple modified Maxwell Garnet (MMMG) and Effective Medium theory (EM) and results are compared with experiment to understand the occurrence of PBG. Our calculations of Lamb shifts including fluctuations are given and compared with those of literature values. We have also done band structure calculations including anisotropy and compared isotropic characteristic of liquid crystal. A possibility of lowest refractive index contrast useful for the fabrication of PBG is given. Our calculations for relative width as a function of refractive index contrast are reported and comparisons with existing theoretical and experimental optimal values are briefed. Applications of photonic crystals are summarized. The investigations conducted on PBG materials and reported here may pave the way for understanding the challenges in the field of PBG. (author)

  11. Some isomorphic properties ofm-polar fuzzy graphs with applications.

    Science.gov (United States)

    Ghorai, Ganesh; Pal, Madhumangal

    2016-01-01

    The theory of graphs are very useful tool in solving the combinatorial problems in different areas of computer science and computational intelligence systems. In this paper, we present a frame work to handle m -polar fuzzy information by combining the theory of m -polar fuzzy sets with graphs. We introduce the notion of weak self complement m -polar fuzzy graphs and establish a necessary condition for m -polar fuzzy graph to be weak self complement. Some properties of self complement and weak self complement m -polar fuzzy graphs are discussed. The order, size, busy vertices and free vertices of an m -polar fuzzy graphs are also defined and proved that isomorphic m -polar fuzzy graphs have same order, size and degree. Also, we have presented some results of busy vertices in isomorphic and weak isomorphic m -polar fuzzy graphs. Finally, a relative study of complement and operations on m -polar fuzzy graphs have been made. Applications of m -polar fuzzy graph are also given at the end.

  12. Physical properties of organic and biomaterials: Fundamentals and applications

    Science.gov (United States)

    Steven, Eden

    Silk materials are natural protein-based materials with an exceptional toughness. In addition to their toughness, silk materials also possess complex physical properties and functions resulting from a particular set of amino-acid arrangement that produces structures with crystalline beta-sheets connected by amorphous chains. Extensive studies have been performed to study their structure-function relationship leading to recent advancements in bio-integrated devices. Applications to fields other than textiles and biomedicine, however, have been scarce. In this dissertation, an investigation of the electronic properties, functionalization, and role of silk materials (spider silk and Bombyx mori cocoon silk) in the field of organic materials research is presented. The investigation is conducted from an experimental physics point of view where correlations with charge transport mechanisms in disordered, semiconducting, and insulating materials are made when appropriate. First, I present the electronic properties of spider silk fibers under ambient, humidified, iodized, polar solvent exposure, and pyrolized conditions. The conductivity is exponentially dependent on relative humidity changes and the solvent polarity. Iodine doping increases the conductivity only slightly but has pronounced effects on the pyrolization process, increasing the yield and flexibility of the pyrolized silk fibers. The iodized samples were further studied using magic angle spinning nuclear magnetic resonance (MAS-NMR) and Fourier transform infrared spectroscopy (FTIR) revealing non-homogenous iodine doping and I2 induced hydrogenation that are responsible for the minimal conductivity improvement and the pyrolization effects, respectively. Next, I present the investigation of silk fiber functionalization with gold and its role in electrical measurements. The gold functionalized silk fiber (Au-SS) is metallic down to cryogenic temperatures, has a certain amount of flexibility, and possesses

  13. Application of Tietz potential to study optical properties of spherical ...

    Indian Academy of Sciences (India)

    E-mail: rezakh2025@yahoo.com. MS received 25 October 2013; revised ... The physical properties of semiconductors such as optical, electronic, and thermodynamic properties have become the most ... Recently, optical and electronic properties of semiconductors have attracted consider- able attention in physics. Optical ...

  14. Facile hydrothermal method for synthesizing nitrogen-doped graphene nanoplatelets using aqueous ammonia: dispersion, stability in solvents and thermophysical performances

    Science.gov (United States)

    Shafiah Shazali, Siti; Amiri, Ahmad; Zubir, Mohd. Nashrul Mohd; Rozali, Shaifulazuar; Zakuan Zabri, Mohd; Sabri, Mohd Faizul Mohd

    2018-03-01

    A simple and green approach has been developed to synthesize nitrogen-doped graphene nanoplatelets (N-doped GNPs) for mass production with a very high stability in different solvents e.g. water, ethylene glycol, methanol, ethanol, and 1-hexanol. The strategy is based on mild oxidation of GNPs using hydrogen peroxide and doping with nitrogen using hydrothermal process. The modification of N-doped GNPs was demonstrated by FTIR, TGA, XPS, Raman spectroscopy and high resolution-transmission electron microscope (HRTEM). Further study was carried out by using N-doped GNPs as an additive to prepare different colloidal dispersions. Water-based N-doped GNPs, methanol-based N-doped GNPs, ethanol-based N-doped GNPs, ethylene-glycol based N-doped GNPs and 1-hexanol-based N-doped GNPs dispersions at 0.01 wt.% shown great colloidal stabilities, indicating 17%, 29%, 33%, 18%, and 43% sedimentations after a 15-days period, respectively. The thermophysical properties e.g., viscosity and thermal conductivity of water-based N-doped GNP nanofluids were also evaluated for different weight concentrations of 0.100, 0.075, 0.050, and 0.025 wt.%. Through this, it is found that the obtained dispersions have great potential to be used as working fluids for industrial thermal systems.

  15. Electronic structure, magnetic, mechanical and thermo-physical behavior of double perovskite Ba2MgOsO6

    Science.gov (United States)

    Dar, Sajad Ahmad; Srivastava, Vipul; Sakalle, Umesh Kumar; Parey, Vanshree

    2018-02-01

    The electronic structure, the magnetic, elasto-mechanical and thermodynamic belongings of cubic double oxide perovskites Ba2MgOsO6 have been successfully investigated within the full potential linearized augmented plane wave method (FP-LAPW), based upon the density functional theory (DFT). The structural examination reveals ferromagnetic stability and the spin polarized electronic band structure and density of states display half-metallic nature of the compound. The calculated magnetic moment was found to have an integer value of 2μ_B. From the knowledge of obtained elastic constants mechanical properties like Young's modulus ( E), shear modulus ( G), Poisson ratio (ν) and the anisotropic factor have been predicted. The calculated B/ G and Cauchy pressure ( C_{12}-C_{44}) both portray the ductile nature of the compound. For a complete understanding of the thermo-physical behavior of vital parameters like heat capacity, thermal expansion, Grüneisen parameter and Debye temperature were predicted using quasi harmonic Debye approximation.

  16. [Application of near infrared spectroscopy in analysis of wood properties].

    Science.gov (United States)

    Yao, Sheng; Pu, Jun-wen

    2009-04-01

    There is substantial interest in the improvement of wood properties through genetic selection or a change in silviculture prescription. Tree breeding purpose requires measurement of a large number of samples. However, traditional methods of assessing wood properties are both time consuming and destructive, limiting the numbers of samples that can be processed, so new method would be needed to find. Near infrared spectroscopy (NIR) is an advanced spectroscopic tool for nondestructive evaluation of wood and it can quickly, accurately estimate the properties of increment core, solid wood or wood meal. The present paper reviews the advances in the research on the wood chemistry properties and anatomical properties using NIR.

  17. Adsorption Properties and Potential Applications of Bamboo Charcoal: A Review

    Directory of Open Access Journals (Sweden)

    Isa S.S.M.

    2016-01-01

    Full Text Available Bamboo charcoal was produced by pyrolysis or carbonization process with extraordinary properties such as high conductivity, large surface area and adsorption property. These properties can be improved by activation process that can be done thermally or chemically. In this paper, carbonization and activation process of bamboo, its structural and adsorption properties will be presented. Herein, the adsorption properties of bamboo charcoal that has fully utilized in solar cell as the electrode, adsorbent for water purification and electromagnetic wave absorber are reviewed.

  18. Optical Properties and Biological Applications of Electromagnetically Coupled Metal Nanoparticles

    Science.gov (United States)

    Sheikholeslami, Sassan Nathan

    The optical properties of metallic particles change dramatically as the size shrinks to the nanoscale. The familiar mirror-like sheen of bulk metals is replaced by the bright, sharp, colorful plasmonic resonances of nanoparticles. The resonances of plasmonic metal nanoparticles are highly tunable throughout the visible spectrum, depending on the size, shape, local dielectric environment, and proximity to other optical resonances. Fundamental and applied research in the nanoscience community in the past few decades has sought to understand and exploit these phenomena for biological applications. In this work, discrete nanoparticle assemblies were produced through biomolecular interactions and studied at the single particle level with darkfield spectroscopy. Pairs of gold nanoparticles tethered by DNA were utilized as molecular rulers to study the dynamics of DNA bending by the restriction enzyme EcoRV. These results substantiated that nanoparticle rulers, deemed "plasmon rulers", could measure the dynamics of single biomolecules with high throughput, long lifetime, and high temporal resolution. To extend these concepts for live cell studies, a plasmon ruler comprised of peptide-linked gold nanoparticle satellites around a core particle was synthesized and utilized to optically follow cell signaling pathways in vivo at the single molecule level. The signal provided by these plasmon rulers allowed continuous observation of caspase-3 activation at the single molecule level in living cells for over 2 hours, unambiguously identifying early stage activation of caspase-3 in apoptotic cells. In the last section of this dissertation, an experimental and theoretical study of electomagnetic coupling in asymmetric metal nanoparticle dimers is presented. A "heterodimer" composed of a silver particle and a gold particle is observed to have a novel coupling between a plasmon mode (free electron oscillations) and an inter-band absorption process (bound electron transitions). The

  19. Marine Bioactives: Pharmacological Properties and Potential Applications against Inflammatory Diseases

    Science.gov (United States)

    D’Orazio, Nicolantonio; Gammone, Maria Alessandra; Gemello, Eugenio; De Girolamo, Massimo; Cusenza, Salvatore; Riccioni, Graziano

    2012-01-01

    Inflammation is a hot topic in medical research, because it plays a key role in inflammatory diseases: rheumatoid arthritis (RA) and other forms of arthritis, diabetes, heart diseases, irritable bowel syndrome, Alzheimer’s disease, Parkinson’s disease, allergies, asthma, even cancer and many others. Over the past few decades, it was realized that the process of inflammation is virtually the same in different disorders, and a better understanding of inflammation may lead to better treatments for numerous diseases. Inflammation is the activation of the immune system in response to infection, irritation, or injury, with an influx of white blood cells, redness, heat, swelling, pain, and dysfunction of the organs involved. Although the pathophysiological basis of these conditions is not yet fully understood, reactive oxygen species (ROS) have often been implicated in their pathogenesis. In fact, in inflammatory diseases the antioxidant defense system is compromised, as evidenced by increased markers of oxidative stress, and decreased levels of protective antioxidant enzymes in patients with rheumatoid arthritis (RA). An enriched diet containing antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic substances, has been suggested to improve symptoms by reducing disease-related oxidative stress. In this respect, the marine world represents a largely untapped reserve of bioactive ingredients, and considerable potential exists for exploitation of these bioactives as functional food ingredients. Substances such as n-3 oils, carotenoids, vitamins, minerals and peptides provide a myriad of health benefits, including reduction of cardiovascular diseases, anticarcinogenic and anti-inflammatory activities. New marine bioactives are recently gaining attention, since they could be helpful in combating chronic inflammatory degenerative conditions. The aim of this review is to examine the published studies concerning the potential pharmacological properties and

  20. A review of extractions of seaweed hydrocolloids: Properties and applications

    Directory of Open Access Journals (Sweden)

    H. P. S. Abdul Khalil

    2018-04-01

    Full Text Available The term hydrocolloid generally refers to substances that form gels or provide viscous dispersion in the presence of water. Alginate, agar, and carrageenan are three commercially valuable hydrocolloids derived from certain brown and red seaweed and each has their distinct physicochemical properties (i.e. functional and bioactive. Various applications of these seaweed hydrocolloids as thickeners, stabilizers, coagulants and salves (in the wound and burn dressings and materials to produce bio-medical impressions in the food, pharmaceutical, and biotechnology industries are highlighted in this review. Although the existing industrial methods of extraction for these seaweed hydrocolloids are well-established, still growing demand has exposed certain limitations of those methods, notably efficiency and product consistency. In order to achieve targeted hydrocolloids for specific purposes and functionalities, some novel and green extraction methods have also been proposed and discussed. Microwave-assisted extraction (MAE, ultrasound-assisted extraction (UAE, enzyme-assisted extraction (EAE, supercritical fluid extraction (SFE, pressurized solvent extractions (PSE, reactive extrusion and photobleaching process are selectively presented as highly promising candidates that can avoid the use of chemicals and provide novel means of access to seaweed hydrocolloids with both economic and environmental benefits. However, this review does not provide the ‘best’ method or procedure as many are still under development. Hence, the review gives ‘food for thought’as to new processes which might be adopted industrially and concluded that further research is required in order to contribute additional new knowledge and refinement to this field of study.