In present work, semiconducting iron (III) oxide (Fe2O3) nanoparticles have been synthesized by sol–gel method. X-ray diffraction (XRD), UV–Visible (UV–Vis) absorption spectroscopy and transmission electron microscopy (TEM) have been used for the characterization of the synthesized nanoparticles. Two-step technique was used to formulate stable ethylene glycol (EG) based Fe2O3 nanofluids at room temperature

Proficiency testing on calibration by comparison of platinum resistance thermometers (PRTs) among several calibration laboratories in Korea was conducted. The challenges faced in organizing this proficiency testing were the required wide temperature range (from − 196 °C to 650 °C) and the large number of participants (43). Maintaining the stability of the test items was key to achieving the goal of

This paper analyzes a homogeneous thermoelectric (TE) circular cylinder as well as an exponentially graded TE cylinder under three-dimensional (3D) conditions. Analytical solutions of the temperature fields are obtained using an eigenfunction expansion method. The energy conversion efficiencies are determined and the material property gradation and leg geometry effects are examined. For the homogeneous

In this research, a novel aqueous solvent, i.e., nanoparticle-enhanced ionic liquid (NEIL), is proposed for CO2 capture by mixing of MEA as the base fluid and [Bmim]BF4 ionic liquid and TiO2 nanoparticles as chemical additives. Then, the flow hydrodynamics, mass transfer characteristics, and CO2 absorption performance of the proposed solvent are investigated in a T-shaped microchannel structure by

The geometry of the cladding pass cross section cannot be easily predicted in laser melting deposition. Due to the huge difference between the actual and the predicted cross section, it is difficult to conduct numerical simulations. In this paper, the finite element method (FEM) with thermal–mechanical coupling is performed. A novel cladding pass cross section model, isosceles trapezoid model, is proposed

In this paper, the heat transfer characteristics of nanofluid nucleate and film boiling are studied experimentally. For this purpose, Al2O3 and SiO2 ethanol-based nanofluids prepared with three volumetric concentrations of 0.1 %, 0.3 %, and 0.5 %. The boiling experiments were conducted on a circular and polished copper surface with a diameter of 25 mm. The results showed that the addition of nanoparticles

The thermal diffusivity of evacuated and liquid-saturated borosilicate glass sieves (frits) of porosities between 20 % and 48 % is presented as measured at room temperature. The saturants cover a range in thermal diffusivity from 0.091 mm2·s−1 to 0.143 mm2·s−1. The runs were carried out using a transient hot bridge (THB) measuring instrument of an expanded uncertainty of 5 % to 10 %. The experimental

Theoretical aspects and practical realization of a new method of fast measurement of thermal conductivity of coating materials (like deposits on wall and tubes of the boilers using fossil fuel, or high-temperature ceramics and adhesive materials) are presented. The method is based on analytical solution of the problem of unsteady heat transfer from the heated probe with coating to the environmental

Diffusion coefficient of water in nitrogen (Dvg) is a critical thermophysical parameter. However, the widely used empirical parametrizations of Dvg are only applicable in the temperature range from 273 K to 373 K. In the supercooled range, the reported experimental values of Dvg is sparse, and Dvg varies with temperature in a way different from the empirical equations and the recently reported first-principles

This study determined the optimal dispersion conditions of nanofluids by orthogonal experiments. Stable graphene/propylene glycol nanofluids are successfully prepared by a "two-step method" using a 60 wt % propylene glycol deionized water solution as the base fluid, and its thermal conductivity and viscosity are evaluated. Additionally, the effects of the graphene mass concentration and nanofluid temperature

A new wide-ranging correlation for the thermal conductivity of xenon, based on the most recent theoretical calculations and critically evaluated experimental data, is presented. The correlation is designed to be used with a high-accuracy Helmholtz equation of state, and it is valid from the triple-point temperature to 606 K and pressures up to 400 MPa. The estimated expanded uncertainty (at a coverage

In this study, research has been carried out in which the optimum insulation thickness for the thermal insulation of buildings in all city centers of Turkey is determined according to life cycle cost analysis. Besides, the total annual net savings of the buildings in all city centers and the payback period of the insulation were concluded according to the determined optimum insulation thickness. In

Buckypapers (BPs) are porous films of randomly oriented carbon nanotubes (CNTs), and have potential applications in many fields. To get better performance, the properties of BPs are needed to be tuned to meet the demands of various applications. In this paper, the effects of annealing on tuning the Young’s modulus, the electrical conductivity, and the thermal conductivity of BPs were studied. Our results

On-site thermometer calibration by the temperature scale transfer technique based on fixed points can effectively improve the calibration level of thermometers in large-diameter hot water pipes. Calibrations of contact thermometers in large-diameter hot water pipes are often carried out using dry block calibrators. Axial temperature gradients and the drift of reference thermometers are the main sources

The aim of this paper is to study and optimize the thermal performance of new lightweight and insulating composite blocks (CBlocks). These CBlocks are made up of a central expanded polystyrene (EPS) layer and two lightweight concrete layers with cavities. The aggregate of the lightweight concrete is pumice. A complete corner wall composed of six composite blocks and a specific corner block is numerically

In this paper, we study the magnetic properties of a tri-layer graphyne-like structure using Blume-Capel Ising model. The studied system is composed by a mixed spins σ = ± 5/2, ± 3/2 and ± 1/2 (in the plane B) and S = ± 2, ± 1 and 0 (in the plane A). The study is performed through Monte Carlo simulations under the Metropolis algorithm. Besides, we examine the effects of the exchange coupling interactions

Nanofluids formed by adding a small volume fraction of solid nanoparticles to the conventional fluid can greatly enhance the thermal transport performance of the conventional fluid. This study reveals the mechanism of thermal conductivity by studying the microscopic effect of nanoparticles in a Cu–Ar nanofluid on the base fluid. Due to the presence of a trapped, adsorbed Ar layer on the surface of

Densities of two synthetic biomethane-like mixtures were measured in the homogeneous liquid phase and the supercritical region using a low-temperature single-sinker magnetic-suspension densimeter. Both mixtures consist of methane, nitrogen, hydrogen and oxygen, whereas the second mixture additionally contains carbon dioxide. For the first mixture, four isotherms from (100 to 160) K were studied over

Ammonium dihydrogen phosphate (ADP) crystal utilizes several applications such as Q-switching, electro-optical, and second harmonic generation in nonlinear optics. In the present article, a good-quality single crystal of ADP was grown via Sankaranarayanan–Ramasamy (SR) method for the dimension of 120 mm in length and 12 mm in diameter. The grown ADP crystal is used for diverse characterizations like

In the field of water content measurement, the calibration of coulometric methods (e.g., coulometric Karl Fischer titration or evolved water vapor analysis) is often overlooked. However, as coulometric water content measurement methods are used to calibrate secondary methods, their results must be obtained with the highest degree of confidence. The utility of calibrating such instruments has been recently

The thermal conductivity of liquid and gas-saturated glass sieves (frits) of porosities between 20 and 48 % is presented as measured at room temperature and ambient pressure. The saturating fluids cover a range in thermal conductivity from 0.018 W⋅m−1⋅K−1 to 0.598 W⋅m−1⋅K−1. The experimental results are fitted to a simple two-dimensional composite model for the heat transfer in porous media. The runs

Group contribution models can be used to predict the thermodynamic properties. The basic data used to determine the interaction parameters are VLE, HE and infinite dilution activity coefficient data. However in the absence of the required data, SLE measurements of eutectic systems are of great interest for fitting interaction parameters of group contribution methods. The knowledge of solid–liquid equilibria

The preparation and utilization of hybrid nanofluids in thermal systems have become popular nowadays owing to their improved thermophysical properties. Although a nanofluid suspension increases the performance of the thermal system, hybrid nanofluids improve the heat transfer performance more by removing the disadvantages of each component. The aqueous hybrid nanofluids consisting of AlN and ZnO nanoparticles

This paper investigates the accuracy of the step-wise transient (SWT) method and proposes a modified model that embodies the real-world experimental setup. The presented model incorporates all the imperfections of the thermocouple and heater, such as the thermal capacity and thermal contact resistance with the specimen. The viability of the proposed hypothesis was confirmed via the experiment simulation

The aim of this study is to improve the thermal performance of air-to-air heat recovery units, containing heat pipes by using graphene/water nanofluid as a working fluid. The experimental set up of this work consists of two air ducts. To study the effect of the airflow rate and the temperature on the performance of the heat recovery unit, different values of airflow rates and temperatures are used

Thermal conductivity of concrete greatly influences the heat transfer of buildings and affected by many factors. This paper presents a prediction model for thermal conductivity of concrete by adopting the theory of Wiener bounds and considering concrete to have four components (water, air, aggregate, and cement mortar). The proposed model considers the combined effects of porosity, water saturation

This paper presents the characterization of solar heat absorber coatings on metal sheets using reduced graphene oxide polymer composites. The reduced graphene oxide (rGO) polymer composite material was evenly coated by the silk-screen method on three types of metal sheets. The thickness of the coated sheet samples was 0.25 mm which were exposed under solar radiation and the variations in temperatures

This work presents the vapor–liquid equilibrium and the interfacial behavior modeling of binary and ternary CO\(_2\) + ester mixtures, with the cubic plus association equation of state (CPA-EOS) combined with the density gradient theory. The binary mixtures, CO\(_2\) + methyl myristate and CO\(_2\) + methyl palmitate, were studied at temperatures from 313.15 K to 333.15 K, considering the ester molecules

The present article deals with the computational fluid dynamics (CFD) investigation of flow and heat transfer of a [C2mim][CH3SO3]/Al2O3 ionanofluid in one conventional tube and two different grooved tubes. The flow is considered to be single-phase and laminar (500 < Re < 2000), and the range of nanoparticle concentration is between 0.05 and 2 %. For properties of the ionanofluid, experimental data

The heating characteristics of ferrite nanoparticles are inconsistent due to various factors that affect the optimum particle size required for maximum power dissipation. The heating mechanism of Fe3O4, MnFe2O4, and Co0.5Fe2.5O4 in the size range 10–40 nm with varying particle size distribution is correlated with the effective specific absorption rate (ESAR). The effective magnetic anisotropy of the

The main objective of the present paper is to propose a new boundary element modeling technique for simulation and optimization of three-temperature micropolar magneto-thermoviscoelastic problems in anisotropic porous smart structures, where we implemented the genetic algorithm (GA), as a method of optimization based on the free form deformation (FFD) methodology to improve the performance of our proposed

This study was designed to assess the possibility of tailoring waste papers and wood dust into composite materials with plaster of Paris (P.O.P) and also determine the suitability of using the developed composites as ceiling panels in building construction. Assorted un-used papers collected as waste materials were processed into waste paper ash (WPA) which was then after utilized like untreated wood

Due to the depletion of the thermal conductivity reference materials, the National Physical Laboratory (NPL) has certified a new thermal conductivity reference material, NPL code 2I09 that is based on Inconel 600. This batch of material has been thermally and electrically characterised over the temperature range 100 °C to 500 °C. The primary thermal conductivity measurements used to generate the certified

Estimation of thermal conductivity of charring composite is a key issue for both design and optimization of an ablative thermal protection system. This paper presents a method for predicting temperature-dependent thermal conductivity of charring ablator using genetic algorithm and cubic spline interpolation, and a special ablative material composed of phenolic resin, glass fibers and quartz fibers

In order to further study the mechanism of heat conduction in bio-tissues, so as to provide a solid theoretical basis for the research of related fields, this paper summarizes in detail the theoretical models used by scholars from various countries to analyze the heat conduction process in the photothermal effect of laser-bio-tissues for many years. The rationality of the theoretical model largely

Research shows that due to enhanced properties IoNanofluids have the potential of being used as heat transfer fluids (HTFs). A significant amount of experimental work has been done to determine the thermophysical and rheological properties of IoNanofluids; however, the number of intelligent models is still limited. In this work, we have experimentally determined the thermal conductivity and viscosity

Due to their special combination of nanostructure and high porosity, aerogels are key materials for high performance thermal insulation. However, measuring reliable thermal conductivity values, which are essential for material’s optimization and as product parameter, is a challenging task in the case of aerogels. Experimentally derived thermal conductivity values for aerogels are so far more or less

The mechanical properties of wood are important factors to demonstrate its suitability in construction and crafts applications. The aim of this study is to evaluate the mechanical parameters for two clones of eucalyptus wood (E. grandis; E. camaldulensis). At 12 % moisture content, axial compression, axial tension, four-points bending and elasticity dynamic modulus resulting from the propagation of

Experimental thermal conductivity of alumina nanoparticles in water is measured with the transient thermal probe, in the presence of sonication (i.e., with ultrasounds), or not. We investigate two types of alumina particles, with the diameter equal to 7 nm and 50 nm. The experimental results, with and without sonication, show that the effective thermal conductivity is greater for the alumina nanoparticle

The single crystals of Cu2ZnSnS4 (CZTS) are grown by direct vapor transport technique. The analysis of X-ray from energy dispersion confirmed that the as-grown single crystals are near stoichiometric. The analysis of the as-grown CZTS single crystals by diffraction of X-ray (XRD) showed the crystal possess tetragonal structure having lattice parameters; a = b = 5.42 Å, c = 10.84 Å and α = β = γ = 90º

An earth air heat exchanger (EAHE) has advantages of its simplicity, easy implementation and low operating cost. The EAHE system is found less expensive for cooling and heating of buildings in severe climates. In this research paper, efforts have been made to analyze the accomplishment of a low-cost cooling system of outdoor air for the hot-dry & hot-humid climate. The effect of velocity, length and

The speed of sound in high-purity n-hexane and n-heptane was experimentally studied utilizing the double-path length pulse-echo technique. Measurements with each alkane were carried out at temperatures from (233 to 353) K with pressures up to 20 MPa. Considering the uncertainty contributions from temperature, pressure, path-length calibration, pulse timing and sample purity, the relative expanded combined

In this work, we present normal spectral emissivity data of solid and liquid molybdenum at a wavelength of 684.5 nm. The presented results are novel measurements on molybdenum, a material, which was already measured 15 years ago by our group. The present results indicate a lower emissivity in the liquid phase. The novel measurements were done within the European Metrology Programme for Innovation and

W360 is a hot work tool steel produced by voestalpine BÖHLER Edelstahl GmbH & Co KG, a special steel producer located in Styria, Austria. Surface tension and density of liquid W360 were studied as a function of temperature in a non-contact, containerless fashion using the oscillating drop method inside an electromagnetic levitation setup. For both, surface tension and density, a linear model was adapted

A vessel containing a classical non-relativistic ideal gas is studied, which has a small hole. Gas effuses through this hole, but the hole is so tiny that the gas inside the vessel remains homogeneous. The density and the temperature of the gas inside the vessel are obtained as functions of time.

Nowadays, it is well known that volumetric heating through microwaves inhibits certain surface properties from being achieved. Similarly, exclusively heating via thermal radiation is neither deep nor homogeneous enough for short periods of time. But combining both approaches can alleviate such issues. In fact, this kind of hybrid heating has been used for many years in real processes for thermal treatment

This work has been dedicated to modeling the vapor–liquid equilibria and surface tension of carboxylic acids + water mixtures at different temperatures. The Peng–Robinson equation of state with modified Huron–Vidal + Wilson mixing rule correctly models the vapor pressure and vapor mole fraction of these mixtures. The modified Huron–Vidal mixing rule was better than quadratic mixing rule to model the

Ionanofluids are mixtures of ionic liquid and solid particles with enhanced thermo-physical properties. Using the properties of these ionanofluids (thermal conductivity, dynamic viscosity, specific heat, and density), a comprehensive analysis concerning their heat transfer capability was performed. Two nanomaterials, silicon carbide (SiC) and graphene dispersed in 1-hexyl-3-methylimidazolium tetrafluoroborate

Here we analyze the Marangoni convective magnetohydrodynamic flow of second grade liquid. Heat transportation is discussed through Joule heating and viscous dissipation. Characteristics of thermo-diffusion and diffusion-thermo are also considered. Gibbs–Marangoni effect is the solutal transfer along the boundary between liquids as a result of gradient of surface tension. Furthermore Bénard–Marangoni

Methods for the determination of the optical properties of both conventional and hybrid nanofluids are presented. The optical properties considered included the extinction coefficient, absorptance, transmittance, and reflectivity. Experimental, theoretical, and numerical approaches for the evaluation of the optical properties are reviewed. The effects of nanoparticle concentration, size, and shape

In this study, the Klein–Gordon equation for the newly proposed generalized Morse potential (GMP) was solved using the newly proposed Nikiforov–Uvarov-functional analysis (NUFA) method for solving central potentials. The analytical expressions of Eigen solutions for GMP were obtained in closed form. The effects of the GMP parameters on the energy eigenvalues have been discussed. The wave function and

Surfactants with a wide range of uses are often preferred to reduce particle aggregation in nanofluid and provide stability. However, added surfactants affect the properties of not only nanofluids but also base fluids. In this study, binary mixtures were prepared by using water and three different surfactants, namely, SDS, Tween 80, and NP 10, in four different concentrations of 0.2 % to 0.8 % by weight

In this study, three different composite materials were produced from mixtures of natural and waste materials in different proportions. The produced composites were used to determine the insulation thickness of exterior walls of buildings located in 12 provinces selected from the four different climate zones of Turkey. The selection of provinces was made according to Turkish standard TS 825. The produced

In this paper, we report a theoretical study of the structural, electronic, thermoelectric and piezoelectric properties of TaXSn (X = Co, Rh and Ir) half-Heusler compounds crystallizing with cubic MgAgAs-type structure. We have made a quantitative evaluation of thermoelectric figure of merit (ZT) and the electromechanical coupling coefficient (k14) of these compounds. Accordingly, we intend to combine

Friction stir welding (FSW) is a solid-state welding process that is finding increasing use in a variety of industries, owing to its ability to create high-quality welds with less heat input than fusion welding. While the modeling of FSW has been an active effort for at least 15 years, two input parameters, namely the friction coefficient and the heat transfer coefficient, are still adjustable quantities

In this study, the spectral emissivity of aeronautical alloy DD6 at eight temperatures (473 K, 523 K, 573 K, 623 K, 673 K, 723 K, 773 K and 823 K) over the spectral range from 3 μm to 20 μm is systematically studied under argon condition. The multi-temperature calibration method is adopted to accurately obtain the FTIR spectrometer response, and then the improved method that eliminates the disturbances

In this research article, the propagation of the plane waves in an initially stressed rotating magneto-thermoelastic solid half-space in the context of fractional-order derivative thermoelasticity is studied. The governing equations in the x–z plane are formulated and solved to obtain a cubic velocity equation that indicates the existence of three coupled plane waves. A reflection phenomenon for the

The present study reports the effective thermal conductivity (ETC) of supercritical (SC) CO2-saturated black coal sample at temperatures from (304.15 to 323.15) K and pressures up to 20 MPa using a steady-state guarded parallel-plate method. The expanded uncertainty of thermal conductivity, pressure, and temperature measurements at the 95 % confidence level with a coverage factor of k = 2 was estimated

The solubilities of benzoic acid, salicylic acid, resorcinol and hydroquinone in water and in 1-octanol were measured by the dynamic method which is also called the synthetic method from 297.25 K to 334.45 K. Using differential scanning calorimetry (DSC Q2000 and SDT Q600), the melting temperature and the enthalpy of fusion of these solutes were determined. The obtained results show that the solubility