Mechanical, Hygric and Thermal Properties of Flue Gas Desulfurization Gypsum

The reference measurements of basic mechanical, thermal and hygric parameters of hardened flue gas desulfurization gypsum are carried out. Moisture diffusivity, water vapor diffusion coefficient, thermal conductivity, volumetric heat capacity and linear thermal expansion coefficient are determined with the primary aim of comparison with data obtained for various types of modified gypsum in the future.

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Thermal Properties of Stabilized Zirconia at Low Temperatures

Australian Journal of Physics ◽

10.1071/ph850617 ◽

1985 ◽

Vol 38 (4) ◽

pp. 617 ◽

Cited By ~ 3

Author(s):

JG Collins ◽

SJ Collocott ◽

GK White

Keyword(s):

Heat Capacity ◽

Thermal Expansion ◽

Thermal Properties ◽

Thermal Expansion Coefficient ◽

Expansion Coefficient ◽

Low Temperatures ◽

Linear Thermal Expansion Coefficient ◽

Linear Thermal Expansion ◽

Stabilized Zirconia ◽

Elastic Data

The linear thermal expansion coefficient a from 2 to 100 K and heat capacity per gram cp from 0�3 to 30 K are reported for fully-stabilized zirconia containing a nominal 16 wt.% (9 mol.%) of yttria. The heat capacity below 7 K has been analysed into a linear (tunnelling?) term, a Schottky term centred at 1�2 K, a Debye term (e~ = 540 K), and a small T5 contribution. The expansion coefficient is roughly proportional to T from 5 to 20 K and gives a limiting lattice Griineisen parameter 'Yo ::::: 5, which agrees with that calculated from elastic data.

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Effects of sonication and freezing on the color, mechanical and thermophysical properties of osmo-microwave-vacuum dried cranberries

Technical Sciences ◽

10.31648/ts.5689 ◽

2020 ◽

Author(s):

Izabela Anna Staniszewska ◽

Szymon Staszyński ◽

Magdalena Zielińska

Keyword(s):

Thermal Conductivity ◽

Heat Capacity ◽

Thermal Diffusivity ◽

Moisture Diffusion ◽

Moisture Diffusivity ◽

Microwave Drying ◽

Vacuum Drying ◽

Volumetric Heat Capacity ◽

Drying Time ◽

Microwave Vacuum Drying

The aim of study was to determine the effects of sonication (S), convective freezing (F), convective freezing preceded by sonication (SF) as well as cryogenic freezing (N) on the osmo-microwave-vacuum drying kinetics, energy usage and properties of dried cranberries such as moisture content, moisture diffusion, water activity, density, porosity, thermal conductivity, thermal diffusivity, volumetric heat capacity, lightness, redness, yellowness, total differences in color, saturation and hue, hardness, cohesiveness, springiness, and chewiness. Osmo-microwave-vacuum drying of cranberries took from 13.5 to 16.0 min. All initial treatments increased the moisture diffusivity and thus reduced the drying time. The most energy effective method was osmo-microwave-vacuum drying preceded by sonication (S) of fruits. Osmo-microwave-drying of cranberries subjected to convective freezing preceded by sonication (SF) resulted in the highest lightness (32.5 ± 0.5), redness (33.9 ± 0.7), and yellowness (11.3 ± 0.5) of fruits, as well as the lowest cohesion (the lowest resistant to stress associated with manufacturing, packaging, storage, and delivery). The lowest hardness, i.e. 12.3 ± 0.4 N and the highest cohesiveness and springiness, i.e. 0.38 ± 0.02 and 0.74 ± 0.03 of dried fruits, were noted for berries subjected to initial cryogenic freezing (N). Cryogenic freezing (N) combined with osmo-microwave-vacuum drying resulted in the largest color changes of fruits and the highest thermal conductivity. Sonicated and convectively frozen (SF) fruits were characterized by the highest thermal diffusivity. Sonication (S), convective freezing (F) and their combination (SF) significantly reduced the volumetric heat capacity of cranberry fruits.

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Structural and thermal properties of the monoclinic Lu2SiO5single crystal: evaluation as a new laser matrix

Journal of Applied Crystallography ◽

10.1107/s0021889809004269 ◽

2009 ◽

Vol 42 (2) ◽

pp. 284-294 ◽

Cited By ~ 36

Author(s):

Hengjiang Cong ◽

Huaijin Zhang ◽

Jiyang Wang ◽

Wentao Yu ◽

Jiandong Fan ◽

...

Keyword(s):

Crystal Structure ◽

Thermal Conductivity ◽

Heat Capacity ◽

Thermal Expansion ◽

Thermal Properties ◽

Specific Heat ◽

Linear Thermal Expansion ◽

Cell Parameters ◽

Thermal Expansion Tensor ◽

Anisotropic Thermal Conductivity

The crystal structure of monoclinic Lu2SiO5(LSO) crystals, grown by the Czochralski method, was determined at room temperature by X-ray diffraction. The unit-cell parameters area= 10.2550 (2),b= 6.6465 (2),c= 12.3626 (4) Å, β = 102.422 (1)° in space groupI2/a. The linear thermal expansion tensor was determined along thea,b,candc* directions over the temperature range from 303.15 to 768.15 K, and the principal coefficients of the thermal expansion tensor are found to be αI= −1.0235 × 10−6 K, αII= 4.9119 × 10−6 K and αIII= 10.1105 × 10−6 K. The temperature dependence of the cell volume and monoclinic angle were also evaluated. In addition, the specific heat and the thermal diffusivity were measured over the temperature ranges from 293.15 to 673.15 K and from 303.15 to 572.45 K, respectively. As a result, the anisotropic thermal conductivity could be calculated and is reported for the first time, to the best of the authors' knowledge. The specific heat capacity of LSO is 139.54 J mol−1 K−1, and the principal components of the thermal conductivity arekI= 2.26 W m−1 K−1,kII= 3.14 W m−1 K−1andkII= 3.67 W m−1 K−1at 303.15 K. A new structure model was proposed to better understand the relationships between the crystal structure and anisotropic thermal properties. In comparison with other laser matrix crystals, it is found that LSO possesses relatively large anisotropic thermal properties, and owing to its small heat capacity it has a moderate thermal conductivity, which is similar to those of the tungstates but lower than those of the vanadates.

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Low Temperature Heat Capacity and Thermal Expansion of KCI Containing a Low Concentration of Li+

Australian Journal of Physics ◽

10.1071/ph870065 ◽

1987 ◽

Vol 40 (1) ◽

pp. 65 ◽

Cited By ~ 2

Author(s):

JG Collins ◽

SJ Collocott ◽

RJ Tainsh ◽

C Andrikidis ◽

GK White

Keyword(s):

Heat Capacity ◽

Thermal Expansion ◽

Linear Thermal Expansion Coefficient ◽

Linear Thermal Expansion ◽

Quantitative Agreement ◽

Impurity Contribution ◽

Temperature Heat ◽

Cationic Site ◽

Splitting Parameter ◽

Low Temperature Heat Capacity

The linear thermal expansion coefficient a from 180 mK to 36 K and the heat capacity per gram cp from 0�5 to 10 Kare reported for KCl containing approximately 100 ppm Li+. Contributions to a and cp attributable to the impurity have been identified and analysed on the basis of a model in which the Li + ions reside about 0�05 nm from the equilibrium cationic site in any of the (111) directions. There is consistent quantitative agreement with a Schottky-like term that arises from the eightfold degeneracy of the level splitting; the splitting parameter is 1� 5 K. The large (- 160) Grtineisen parameter associated with the impurity contribution is evidence for a quantum-mechanical tunnelling process, and agrees with values derived from independent measurements of the spectroscopic and dielectric responses of this system under pressure.

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Thermal Conductivity and Temperature Dependence of Linear Thermal Expansion Coefficient of Al4SiC4 Sintered Bodies Prepared by Pulse Electronic Current Sintering

Journal of the Ceramic Society of Japan ◽

10.2109/jcersj.111.348 ◽

2003 ◽

Vol 111 (1293) ◽

pp. 348-351 ◽

Cited By ~ 29

Author(s):

Koji INOUE ◽

Satoshi MORI ◽

Akira YAMAGUCHI

Keyword(s):

Thermal Conductivity ◽

Thermal Expansion ◽

Temperature Dependence ◽

Thermal Expansion Coefficient ◽

Expansion Coefficient ◽

Linear Thermal Expansion Coefficient ◽

Linear Thermal Expansion ◽

Electronic Current

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Experiment on Thermophysical Properties of Reactive Powder Concrete

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.374-377.1519 ◽

2011 ◽

Vol 374-377 ◽

pp. 1519-1522 ◽

Cited By ~ 2

Author(s):

Hong Bin Liu ◽

Kai Pei Tian ◽

Jin Hui Liu ◽

Yang Ju

Keyword(s):

Thermal Conductivity ◽

Heat Capacity ◽

Thermal Expansion ◽

Thermophysical Properties ◽

Steel Fiber ◽

Linear Thermal Expansion ◽

Reactive Powder Concrete ◽

Fiber Volume ◽

Empirical Relationships ◽

Reactive Powder

In this paper, the thermophysical properties, such as thermal conductivity, thermal diffusivity, specific heat capacity and linear thermal expansion of reactive powder concrete (RPC) with different steel fiber volumetric fractions are investigated by means of thermophysical experiments. The empirical relationships of thermophysical properties with temperature and fiber volume are established. The results indicate the temperature and fiber volumetric fractions have different effects on the thermal properties of RPC.

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Testing a Gypsum Composite Based on Raw Gypsum with a Direct Admixture of Paraffin and Polymer to Improve Thermal Properties

Materials ◽

10.3390/ma14123241 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3241

Author(s):

Krzysztof Powała ◽

Andrzej Obraniak ◽

Dariusz Heim

Keyword(s):

Thermal Conductivity ◽

Heat Capacity ◽

Thermal Properties ◽

Phase Change ◽

Large Scale ◽

Building Materials ◽

Residential Buildings ◽

Energy Performance ◽

Polymer Content ◽

Volumetric Heat Capacity

The implemented new legal regulations regarding thermal comfort, the energy performance of residential buildings, and proecological requirements require the design of new building materials, the use of which will improve the thermal efficiency of newly built and renovated buildings. Therefore, many companies producing building materials strive to improve the properties of their products by reducing the weight of the materials, increasing their mechanical properties, and improving their insulating properties. Currently, there are solutions in phase-change materials (PCM) production technology, such as microencapsulation, but its application on a large scale is extremely costly. This paper presents a solution to the abovementioned problem through the creation and testing of a composite, i.e., a new mixture of gypsum, paraffin, and polymer, which can be used in the production of plasterboard. The presented solution uses a material (PCM) which improves the thermal properties of the composite by taking advantage of the phase-change phenomenon. The study analyzes the influence of polymer content in the total mass of a composite in relation to its thermal conductivity, volumetric heat capacity, and diffusivity. Based on the results contained in this article, the best solution appears to be a mixture with 0.1% polymer content. It is definitely visible in the tests which use drying, hardening time, and paraffin absorption. It differs slightly from the best result in the thermal conductivity test, while it is comparable in terms of volumetric heat capacity and differs slightly from the best result in the thermal diffusivity test.

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Using CPTs to derive thermal properties of soil

E3S Web of Conferences ◽

10.1051/e3sconf/202020504005 ◽

2020 ◽

Vol 205 ◽

pp. 04005

Author(s):

Philip J. Vardon ◽

Joek Peuchen

Keyword(s):

Thermal Conductivity ◽

Heat Capacity ◽

Laboratory Tests ◽

Field Investigation ◽

Volumetric Heat Capacity ◽

Cone Penetration ◽

Cone Penetration Tests ◽

Penetration Tests ◽

Properties Of Soil

A method of utilizing cone penetration tests (CPTs) is presented which gives continuous profiles of both the in situ thermal conductivity and volumetric heat capacity, along with the in situ temperature, for the upper tens of meters of the ground. Correlations from standard CPT results (cone resistance, sleeve friction and pore pressure) are utilized for both thermal conductivity and volumetric heat capacity for saturated soil. These, in conjunction with point-wise thermal conductivity and in situ temperature results using a Thermal CPT (T-CPT), allow accurate continuous profiles to be derived. The CPT-based method is shown via a field investigation supported by laboratory tests to give accurate and robust results.

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