Insects (Arthropoda: Insecta) collected on bovine feces after different times of field exposure in Itumbiara, South of Goias, Brazil

Cross-laminated timber (CLT) market demand is on the rise in the United States. Adequate protective measures have not been extensively studied. The objective of this study was to investigate the weathering performance of exterior wood coatings. We evaluated coated CLT sample surfaces based on visual appearance, color change (CIE*L*a*b), gloss changes, and water intrusion. From the five exterior wood coatings evaluated, only two showed adequate performance after twelve months field exposure. Based on visual ratings following the ASTM procedures, coating failure occurs more quickly in Mississippi than in Wisconsin, due to its greater decay zone. Both location and coating type impacted the aging of the samples. Artificial weathering results were consistent with natural weathering indicating the two adequate coatings were the most resistant to failure, color, and gloss change. For future studies, new coatings designed for the protection of end-grain in CLT panels should be a target of research and development.

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Robust Wireless Power Transfer with Minimal Field Exposure Using Parity-Time Symmetric Microwave Cavities

Physical Review Applied ◽

10.1103/physrevapplied.16.014022 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Sungik Park ◽

Jongheon Lee ◽

Sanghoek Kim

Keyword(s):

Wireless Power Transfer ◽

Power Transfer ◽

Wireless Power ◽

Field Exposure ◽

Microwave Cavities

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Field temperature and moisture loads from a building envelope as the basis for accelerated aging of barrier membranes

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2018-0757 ◽

2019 ◽

Vol 46 (11) ◽

pp. 969-978 ◽

Cited By ~ 2

Author(s):

Marzieh Riahinezhad ◽

Augusta Eve ◽

Marianne Armstrong ◽

Peter Collins ◽

J.-F. Masson

Keyword(s):

Building Materials ◽

National Research Council ◽

Accelerated Aging ◽

Bimodal Distribution ◽

Building Envelope ◽

Rate Of Change ◽

Single Family ◽

Field Exposure ◽

Aging Conditions ◽

Materials Used

Temperature and relative humidity (RH) data within the building envelope of a single-family home at the National Research Council of Canada’s Canadian Centre for Housing Technology were collected over five years. We report on the distribution, rate of change, and the limits of temperature and moisture variations for south-easting wall and south-facing wall and roof systems to better understand the in-situ environmental conditions to which building materials and components typical of homes in North America may be subjected. Over an average year, wall temperature varied from −25 °C to +45 °C, and temperature followed a bimodal distribution, with maxima at 0 °C to 5 °C and 15 °C to 20 °C. Each maximum represented about 1100 h of field exposure. Roof temperatures, which spanned a temperature range from −35 °C to 75 °C, did not show a Gaussian distribution but were characterized as being multi-modal. From values of temperature and RH, absolute moisture contents within the building envelope were found to range between 1 and 55 g/m3, with the most common values being 6–8 g/m3. The application of this information is discussed and related to the development of realistic accelerated aging conditions to obtain a more accurate durability assessment of building envelope materials used in Canadian dwellings.

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