Evolution of Specific Heat Capacity with Temperature for Typical Supports Used for Heterogeneous Catalysts

Heterogeneous catalysts are widely used in the chemical industry. Compared with homogeneous catalysts, they can be easily separated from the reaction mixture. To design and optimize an efficient and safe chemical process one needs to calculate the energy balance, implying the need for knowledge of the catalyst’s specific heat capacity. Such values are typically not reported in the literature, especially not the temperature dependence. To fill this gap in knowledge, the specific heat capacities of commonly utilized heterogeneous catalytic supports were measured at different temperatures in a Tian–Calvet calorimeter. The following materials were tested: activated carbon, aluminum oxide, amberlite IR120 (H-form), H-Beta-25, H-Beta-38, H-Y-60, H-ZSM-5-23, H-ZSM-5-280, silicon dioxide, titanium dioxide, and zeolite 13X. Polynomial expressions were successfully fitted to the experimental data.

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“TEMPERATURE” FLUCTUATION AND HEAT CAPACITIES OF QUARKS AND π MESON

International Journal of Modern Physics E ◽

10.1142/s0218301307007222 ◽

2007 ◽

Vol 16 (07n08) ◽

pp. 1912-1916

Author(s):

X. H. SHI ◽

G. L. MA ◽

Y. G. MA ◽

X. Z. CAI ◽

J. H. CHEN

Keyword(s):

Heat Capacity ◽

Specific Heat ◽

Impact Parameter ◽

Specific Heat Capacity ◽

Temperature Fluctuation ◽

Temperature Fluctuations ◽

Heat Capacities ◽

Transverse Mass ◽

Parton Cascade ◽

Specific Heat Capacities

Specific heat capacities of π meson and different quarks after parton cascade AMPT model in Au + Au collisions at [Formula: see text] have been tentatively extracted from the event-by-event temperature fluctuations in the region of low transverse mass. The specific heat capacity of π meson shows a slight dropping trend with increasing impact parameter. The specific heat capacities of different quarks increase with the mass of quark, and the sum of up and down quark's specific heat capacities was found to be approximately equal to that of π meson.

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Dynamic Compression and Thermo-Physical Properties of Some Wood Particles in South Western Nigeria

Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences ◽

10.52763/pjsir.phys.sci.60.2.2017.79.84 ◽

2017 ◽

Vol 60 (2) ◽

pp. 79-84

Author(s):

Mathew Adefusika Adekoya ◽

Sunday Samuel Oluyamo ◽

Olawale Ramon Bello

Keyword(s):

Heat Capacity ◽

Physical Properties ◽

Specific Heat ◽

Specific Heat Capacity ◽

Dynamic Compression ◽

Dependent Model ◽

Specific Heat Capacities ◽

Temperature Dependent Model ◽

Thermal Diffusivities ◽

Thermo Physical Properties

This study examines the dynamic compression and thermo-physical properties of some woodparticles obtained from Akure, south local government area, Ondo State, South Western Nigeria. Thesewood particles are of the species of Celtis zenkeri and Celtis philippensis of the Ulmaceae family. Thesamples were possessed into different particle sizes (300, 600 and 850 µm) and subjected to variedcompacting pressures (2.6-3.0 MPa). The density and specific heat capacity of the wood samples weredetermined using weighing displacement methods and temperature dependent model while the thermaldiffusivity was estimated from other thermal properties. The results revealed significant variation in thevalues of the specific heat capacity as a result of change in pressure for all the wood samples considered.The density of wood samples lies between 4.51×102 -7.32×102 kg/m3 and the specific heat capacity valuesobtained for the samples fall within the range of 1.28×103-1.33×103 J/kg/K. It was also noted that thethermal diffusivity obtained falls within the range of 1.37×10-7-2.10×10-7 m2/s for the wood materialsconsidered. However, the values of the densities, specific heat capacities and thermal diffusivities of thesamples were found to change as the compacting pressure increased due to decreased in porosity. Theimplication of the study is that the mate

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Suitable model for the calculation of the correlation between the real and the average specific heat capacity and possibilities of its application

Hemijska industrija ◽

10.2298/hemind111104092p ◽

2013 ◽

Vol 67 (3) ◽

pp. 495-511

Author(s):

Branko Pejovic ◽

Ljubica Vasiljevic ◽

Vladan Micic ◽

Mitar Perusic

Keyword(s):

Heat Capacity ◽

Specific Heat ◽

Specific Heat Capacity ◽

Heat Capacities ◽

Practical Significance ◽

Suitable Model ◽

The Real ◽

Temperature Range ◽

Specific Heat Capacities ◽

Differential Properties

Starting from the definition of the average specific heat capacity for chosen temperature range, the analytic dependence between the real and the mean specific heat capacities is obtained using differential and integral calculation. The obtained relation in differential form for the defined temperature range allows for the problem to be solved directly, without any special restrictions on its use. Using the obtained relation, a general model in the form of a polynomial of arbitrary degree in the function of temperature was derived, which has more suitable and faster practical application and is more general in character than the existing model. New graphical method for solving the problem is obtained based on differential geometry and using the derived equation. This may also have practical significance since many problems in thermodynamics are solved analytically and graphically. This result was used in order to obtain the amount of specific heat exchanged using an analytical model or a planimetric method. In addition, this graphical solution was used for the construction of the diagram showing the dependence between the specific heat exchanged and temperature. This diagram also gives a simple graphical procedure for the calculation of the real and the average specific heat capacity for arbitrary temperature or temperature interval. The confirmation for all graphic constructions is obtained using the differential properties between thermodynamic units. In order for the graphical solutions presented to be applicable in practice, suitable ratio coefficients have been determined for all cases. Verification of the model presented, as well as the possibilities of its application, were given using several characteristic examples of semi-ideal and real gas. Apart from linear and non-linear functions in the form of polynomials, the exponential function of the dependence between specific heat capacities and temperature was also analysed in this process.

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Uncertainty estimation of the mean specific heat capacity for the major gases contained in biogas

Research in Agricultural Engineering ◽

10.17221/4/2020-rae ◽

2020 ◽

Vol 66 (No. 2) ◽

pp. 52-59

Author(s):

Petr Travnicek ◽

Ivan Vitázek

Keyword(s):

Heat Capacity ◽

Specific Heat ◽

Specific Heat Capacity ◽

Scientific Work ◽

Uncertainty Estimation ◽

Simple Arithmetic ◽

Capacity Calculation ◽

The Mean ◽

Specific Heat Capacities ◽

The Individual

The paper is focused on the uncertainty estimation of the mean isobaric and isochoric specific heat capacity calculation. The differences in the data among the individual sources for the technical calculation are presented in the first part of the paper. These differences are discussed in this paper. Research of scientific work with listed values of measurement uncertainties has been carried out in the second part of the paper. Furthermore, mathematical models were calculated which describe the dependence of the specific heat capacities and temperature. The maximal error models were carried out. Two approaches were used for the calculation of the mean specific heat capacity. The first approach is the calculation with help of integration of the function which describes the dependence of the specific heat capacity and temperature. The second approach is the calculation of a simple arithmetic mean of the specific heat capacity related to the maximal and minimal value of the temperature interval. The conclusion of the work shows that the time-effective second way is applicable in the case of a narrow temperature range. A value of 5.5% (Δ<sub>t</sub> = 200 K) was reached for the relative uncertainty. This is a similar value to that in the case of using the first way.

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Experimental Study on the Specific Heat Capacity Measurement of Water-Based Al2O3-Cu Hybrid Nanofluid by using Differential Thermal Analysis Method

Current Nanoscience ◽

10.2174/1573413715666191118105331 ◽

2019 ◽

Vol 15 ◽

Author(s):

Andaç Batur Çolak ◽

Oğuzhan Yıldız ◽

Mustafa Bayrak ◽

Ali Celen ◽

Ahmet Selim Dalkılıç ◽

...

Keyword(s):

Heat Capacity ◽

Specific Heat ◽

Specific Heat Capacity ◽

Thermophysical Properties ◽

Volume Concentration ◽

Pure Water ◽

Heat Capacity Measurement ◽

Experimental Results ◽

Hybrid Nanofluid ◽

Capacity Measurement

Background: Researchers working in the field of nanofluid have done many studies on the thermophysical properties of nanofluids. Among these studies, the number of studies on specific heat are rather limited. In the study of the heat transfer performance of nanofluids, it is necessary to increase the number of specific heat studies, whose subject is one of the important thermophysical properties. Objective: The authors aimed to measure the specific heat values of Al2O3/water, Cu/water nanofluids and Al2O3-Cu/water hybrid nanofluids using the DTA method, and compare the results with those frequently used in the literature. In addition, this study focuses on the effect of temperature and volume concentration on specific heat. Method: The two-step method was used in the preparation of nanofluids. The pure water selected as the base fluid was mixed with the Al2O3 and Cu nanoparticles and Arabic Gum as the surfactant, firstly mixed in the magnetic stirrer for half an hour. It was then homogenized for 6 hours in the ultrasonic homogenizer. Results: After the experiments, the specific heat of nanofluids and hybrid nanofluid were compared and the temperature and volume concentration of specific heat were investigated. Then, the experimental results obtained for all three fluids were compared with the two frequently used correlations in the literature. Conclusion: Specific heat capacity increased with increasing temperature, and decreased with increasing volume concentration for three tested nanofluids. Cu/water has the lowest specific heat capacity among all tested fluids. Experimental specific heat capacity measurement results are compared by using the models developed by Pak and Cho and Xuan and Roetzel. According to experimental results, these correlations can predict experimental results within the range of ±1%.

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Development of the room temperature protocol based on room temperature ionic liquids and surfactant ionic liquids for the synthesis of derivatives of 2-amino-thiazoles and thermo-physical analysis of the synthesized derivatives using TGA-DSC.

Current Physical Chemistry ◽

10.2174/1877946810999200519102040 ◽

2020 ◽

Vol 10 ◽

Cited By ~ 1

Author(s):

Chandrakant Sarode ◽

Sachin Yeole ◽

Ganesh Chaudhari ◽

Govinda Waghulde ◽

Gaurav Gupta

Keyword(s):

Thermal Analysis ◽

Heat Capacity ◽

Ionic Liquids ◽

Specific Heat ◽

Specific Heat Capacity ◽

Room Temperature ◽

Heat Capacity Data ◽

General Strategy ◽

Capacity Data ◽

Derivatives Of

Aims: To develop an efficient protocol, which involves an elegant exploration of the catalytic potential of both the room temperature and surfactant ionic liquids towards the synthesis of biologically important derivatives of 2-aminothiazole. Objective: Specific heat capacity data as a function of temperature for the synthesized 2- aminothiazole derivatives has been advanced by exploring their thermal profiles. Method: The thermal gravimetry analysis and differential scanning calorimetry techniques are used systematically. Results: The present strategy could prove to be a useful general strategy for researchers working in the field of surfactants and surfactant based ionic liquids towards their exploration in organic synthesis. In addition to that, effect of electronic parameters on the melting temperature of the corresponding 2-aminothiazole has been demonstrated with the help of thermal analysis. Specific heat capacity data as a function of temperature for the synthesized 2-aminothiazole derivatives has also been reported. Conclusion: Melting behavior of the synthesized 2-aminothiazole derivatives is to be described on the basis of electronic effects with the help of thermal analysis. Additionally, the specific heat capacity data can be helpful to the chemists, those are engaged in chemical modelling as well as docking studies. Furthermore, the data also helps to determine valuable thermodynamic parameters such as entropy and enthalpy.

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Influence of alkaline modification on selected properties of banana fiber paperbricks

Scientific Reports ◽

10.1038/s41598-021-85106-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Abayomi A. Akinwande ◽

Adeolu A. Adediran ◽

Oluwatosin A. Balogun ◽

Oluwaseyi S. Olusoju ◽

Olanrewaju S. Adesina

Keyword(s):

Thermal Conductivity ◽

Heat Capacity ◽

Specific Heat ◽

Specific Heat Capacity ◽

Moisture Absorption ◽

Water Volume ◽

Banana Fiber ◽

Fiber Loading ◽

Banana Fibers ◽

Alkaline Modification

AbstractIn a bid to develop paper bricks as alternative masonry units, unmodified banana fibers (UMBF) and alkaline (1 Molar aqueous sodium hydroxide) modified banana fibers (AMBF), fine sand, and ordinary Portland cement were blended with waste paper pulp. The fibers were introduced in varying proportions of 0, 0.5, 1.0 1.5, 2.0, and 2.5 wt% (by weight of the pulp) and curing was done for 28 and 56 days. Properties such as water and moisture absorption, compressive, flexural, and splitting tensile strengths, thermal conductivity, and specific heat capacity were appraised. The outcome of the examinations carried out revealed that water absorption rose with fiber loading while AMBF reinforced samples absorbed lesser water volume than UMBF reinforced samples; a feat occasioned by alkaline treatment of banana fiber. Moisture absorption increased with paper bricks doped with UMBF, while in the case of AMBF-paper bricks, property value was noted to depreciate with increment in AMBF proportion. Fiber loading resulted in improvement of compressive, flexural, and splitting tensile strengths and it was noted that AMBF reinforced samples performed better. The result of the thermal test showed that incorporation of UMBF led to depreciation in thermal conductivity while AMBF infusion in the bricks initiated increment in value. Opposite behaviour was observed for specific heat capacity as UMBF enhanced heat capacity while AMBF led to depreciation. Experimental trend analysis carried out indicates that curing length and alkaline modification of fiber were effective in maximizing the properties of paperbricks for masonry construction.

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A novel model for predicting the effective specific heat capacity of molten salt doped with nanomaterial for solar energy application

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2021.117129 ◽

2021 ◽

pp. 117129

Author(s):

Fan Yuan ◽

Ming-Jia Li ◽

Ya-Ling He ◽

Wen-Quan Tao

Keyword(s):

Heat Capacity ◽

Solar Energy ◽

Specific Heat ◽

Molten Salt ◽

Specific Heat Capacity ◽

Solar Energy Application ◽

Effective Specific Heat ◽

Energy Application ◽

Novel Model

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Effects of SiO2 Nanoparticle Dispersion on The Heat Storage Property of the Solar Salt for Solar Power Applications

Energies ◽

10.3390/en14030703 ◽

2021 ◽

Vol 14 (3) ◽

pp. 703

Author(s):

Zhao Li ◽

Liu Cui ◽

Baorang Li ◽

Xiaoze Du

Keyword(s):

Heat Capacity ◽

Specific Heat ◽

Specific Heat Capacity ◽

Heat Storage ◽

Md Simulations ◽

Interfacial Thermal Resistance ◽

Solar Salt ◽

Salt Ions ◽

Base Salt ◽

Storage Property

The effects of SiO2 nanoparticles on the heat storage properties of Solar Salt (NaNO3-KNO3) are studied using experimental and molecular dynamics (MD) simulations. The experiment results show the specific heat capacity of the molten salt-based nanofluids is higher than that of the pure base salt. We focus on the inference regarding the possible mechanisms behind the enhancement of the specific heat capacity which are considered more acceptable by the majority of researchers, the energy and force in the system are analyzed by MD simulations. The results demonstrate that the higher specific heat capacity of the nanoparticle is not the reason leading to the heat storage enhancement. Additionally, the analysis of potential energy and system configuration shows that the other possible mechanisms (i.e., interfacial thermal resistance theory and compressed layer theory) are only superficial. The forces between the nanoparticle atoms and base salt ions construct the constraint of the base salt ions, further forms the interfacial thermal resistance, and the compressed layer around the nanoparticle. This constraint has a more stable state and requires more energy to deform it, leading to the improvement of the heat storage property of nanofluids. Our findings uncover the mechanisms of specific heat capacity enhancement and guide the preparation of molten salt-based nanofluids.

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