Measurement of low-thermal effusivity of building materials using thermal impedance method

Abstract Thermal performance of building materials is an important parameter from the point of view of energy consumption for heating buildings, which is obviously related to environmental protection standards. Thermal parameters of roofing slates were measured for samples from two different formations in the Czech Republic. These were rocks of lower Carboniferous Culm facies of Moravice Formation and Silesian Unit of Flysch Moravian-Silesian Carpathians. Thermal conductivity and thermal effusivity measurements were performed with use of TCi analyser. Thermal parameters were obtained in parallel and perpendicular direction to the bedding in rocks. Thermal conductivity of the Moravian slates in the direction perpendicular to the bedding ranges from 1.43 to 1.79 W m−1 K−1, while for samples from Carpathian region this parameter ranges from 1.99 to 3.15 W m−1 K−1. High values of thermal conductivity correlate to higher quartz content in the rocks. The measured thermal parameters (conductivity, effusivity, diffusivity) are strongly depending on the direction of measurement. Thermal conductivity of analysed rocks increases along with increase in temperature. The increase in thermal conductivity value is more significant in case of Moravian slates. In practice, the obtained results indicate that the traditional building material, such as roofing slates, shows better insulation properties at lower temperatures, while in conditions of strong sunlight the temperature conductivity increases. In case of roofing slates, which tend to be highly anisotropic, the essential information is the direction of thermal parameters measurement. Slates, due to their specific texture, are characterized by a very high thermal anisotropy coefficient.

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3-Omega-T-Type Method for Measuring the Thermophysical Properties of Micro/Nanowires

ASME 2011 9th International Conference on Nanochannels, Microchannels, and Minichannels, Volume 2 ◽

10.1115/icnmm2011-58018 ◽

2011 ◽

Author(s):

Xing Zhang ◽

Jianli Wang

Keyword(s):

Thermal Contact Resistance ◽

Thermal Contact ◽

Thermal Effusivity ◽

Temperature Oscillation ◽

Thermal Impedance ◽

Hot Wire ◽

Type Method ◽

3 Omega ◽

Interstitial Material ◽

Lock In

A novel 3ω-T type probe method is developed to investigate the thermal effusivity of micro/nanowires. In this method, a short hot wire subjected to an alternating current serves simultaneously as a heater and a thermometer, and a test wire is attached to the midpoint of the hot wire with an interstitial material. A measurement system based on a virtual lock-in is developed to measure the thermal impedance of the interposer and the thermal effusivity of the test wire. The same value of thermal effusivity is obtained with the presence of different interposers, and the interposer with small thermal impedance gives a decrease of the temperature oscillation of the hot wire. Using this method, the thermal resistances of bare metallic junctions are measured as a function of temperature. For the junction established by two crossed platinum wires with small diameters, the thermal contact resistance is found to decrease as temperature increases, which can possibly be explained the plastic deformation of the microscopic contacts.

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Thermal conductivity of Gd2 Zr2 O7 thin films using thermal-impedance method

physica status solidi (a) ◽

10.1002/pssa.201000073 ◽

2011 ◽

Vol 208 (5) ◽

pp. 1105-1110 ◽

Cited By ~ 7

Author(s):

J. W. Kim ◽

G. E. Jeong ◽

Ho-Soon Yang

Keyword(s):

Thin Films ◽

Thermal Conductivity ◽

Impedance Method ◽

Thermal Impedance

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Scanning electron microscopy of asbestos-containing material where the asbestos fibers are considered locked in a binder

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148198 ◽

1993 ◽

Vol 51 ◽

pp. 472-473

Author(s):

J. R. Millette ◽

R. S. Brown

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Environmental Protection Agency ◽

Building Materials ◽

The United States ◽

Protection Agency ◽

Asbestos Fibers ◽

Different Types ◽

Binder Material ◽

Scanning Electron

The United States Environmental Protection Agency (EPA) has labeled as “friable” those building materials that are likely to readily release fibers. Friable materials when dry, can easily be crumbled, pulverized, or reduced to powder using hand pressure. Other asbestos containing building materials (ACBM) where the asbestos fibers are in a matrix of cement or bituminous or resinous binders are considered non-friable. However, when subjected to sanding, grinding, cutting or other forms of abrasion, these non-friable materials are to be treated as friable asbestos material. There has been a hypothesis that all raw asbestos fibers are encapsulated in solvents and binders and are not released as individual fibers if the material is cut or abraded. Examination of a number of different types of non-friable materials under the SEM show that after cutting or abrasion, tuffs or bundles of fibers are evident on the surfaces of the materials. When these tuffs or bundles are examined, they are shown to contain asbestos fibers which are free from binder material. These free fibers may be released into the air upon further cutting or abrasion.

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History and Methods of Testing Building Materials

Scientific American ◽

10.1038/scientificamerican05091896-16975bsupp ◽

1896 ◽

Vol 41 (1062supp) ◽

pp. 16975-16977

Keyword(s):

Building Materials

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Architecture and Building Materials

Scientific American ◽

10.1038/scientificamerican11261859-353 ◽

1859 ◽

Vol 1 (22) ◽

pp. 353-353

Keyword(s):

Building Materials

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Legal framework for improvement of agroecology by cultivating jerusalem artichoke

Scientific and Informational Bulletin of Ivano-Frankivsk University of Law Named after King Danylo Halytskyi - Scientific and informational bulletin of Ivano-Frankivsk University of Law named after King Danylo Halytskyi ◽

10.33098/2078-6670.2020.9.21.59-66 ◽

2020 ◽

pp. 59-66

Author(s):

Mykhailo Kosmii ◽

Vasyl. Kasiianchuk ◽

Ruslan Zhyrak ◽

Ivan Krykhovetskyi

Keyword(s):

Environmental Protection ◽

Organic Farming ◽

Alternative Energy ◽

Building Materials ◽

Environmental Law ◽

Jerusalem Artichoke ◽

Legal Framework ◽

Legal Regulation ◽

Practical Application ◽

Scientific Cognition

The purpose of this paper is to analyze and research the legal mechanisms which make it possible to improve agroecology through the organization of cultivation of Jerusalem artichoke.Methodology. The methodology includes comprehensive analysis and generalization of available scientific, theoretical, practical and applied material and development of relevant conclusions and recommendations. During the research, the following methods of scientific cognition were used: dialectical, terminological, historical and legal, logical and normative, systemic and structural, functional, normative and dogmatic, generalization methods. Results. The process of analysis and research highlighted the possibilities of cultivating Jerusalem artichoke for improving agroecology, namely improving the ecological state of the atmosphere air and soil, preparing them for organic farming. The article contains examples of practical application of tubers of Jerusalem artichoke and herbage for the production of therapeutic and prophylactic products, alternative energy and highly efficient building materials. Scientific novelty. The study found that the authors summarized and systematized the levels of legal regulation in the field of using Jerusalem artichoke for improving agroecology, preparing soil for organic farming, in particular: the inter-sectoral level which covers the interaction of agricultural and environmental law in terms of cultivation and use of Jerusalem artichoke; the level of integrated environmental and legal regulation; level of individual resource (floristic) legal regulation; the level of environmental protection (anthropoprotection) legislation.Practical importance. The results of the study can be used in law-making and environmental protection activities related to issues of cultivating and using the Jerusalem artichoke as a means of improving agroecology.

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