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-destructive, possibly providing information in the form of imaging which can readily be interpreted. The infrared thermography (IRT) is a technique currently used for the non-destructive characterizations in a large variety of different fields and, during the

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G. M. Carlomagno 2004 Recent advances in the use of infrared thermography Meas Sci Technol 15 27 – 58

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Abstract  

Thermal investigations using infrared (IR) thermometry and false colour thermography were carried out on flowering plants in the Botanical Garden of Berlin and in a private garden. Special interest went to phototropic plants that orient their blossoms towards a light source (mainly the sun) and within this group to solar trackers (heliotropism) that follow the path of the sun during the day. Best known among the latter is the sunflower. Bowl shaped flowers comparable to satellite disks focus the solar radiation effectively on their centre, resulting in a warming of the female organs at that point. Temperature differences above ambient can be as high as 10.7 K with a mean value of 6.0 K. Pollinating insects were often observed sun-basking in the bowls or on the flower disks attracted by energetic rewards in form of nectar and heat.

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Abstract  

The structure and the preservation state of artistic heritage and archaeological findings have been studied by the analysis of the heat diffusion process in the sample. The investigations have been performed by non-invasive time resolved infrared thermography(IRT). Thickness maps, buried defects detection, inhomogeneity and corrosion analysis, as well as the quality check of welding and reinforcements elements, have been performed on the studied samples.

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In rain-fed agricultural regions, limited rainfall and frequent unpredictable droughts have resulted in low and variable wheat yields. Balanced water use between root water-uptake and remaining soil moisture is a key factor for drought adaptation. Thirteen recombinant inbred lines selected from a backcross population of synthetic-derived bread wheat were examined for the association among root water-uptake ability, grain yield and root elongation under limited water conditions using pot and field experiments. The effect of wax coating on grain formation under soil desiccation was also studied in two selected genotypes. There were significant variations in both root water-uptake ability estimated in pot experiments and grain yield obtained in field experiments among wheat genotypes. Infrared thermography indicated that canopy temperature was related to the leaf transpiration due to root water-uptake. A significant negative correlation was found between root water-uptake ability and grain weight, suggesting that lower root water-uptake ability was associated with higher grain weight. Genotype SYN-10 had the lowest water-uptake ability and the highest grain weight, indicating a type of ‘water-saving wheat’. Wax coating significantly reduced root water-uptake in wheat genotypes SYN-8 and SYN-10. Infrared thermography showed an increased leaf temperature due to the transpiration-suppression effect of the wax coating. Reductions in grain yield due to soil desiccation were found in SYN-8, but not in SYN-10. The higher grain yield of SYN-10 was attributed to more grains under soil desiccation. Grain yield of SYN-10 was decreased by the wax coating under soil desiccation. Dehydration tolerance of SYN-10 might be associated with the transpiration process of the leaves.

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-rays, or infrared thermography [ 6–8 ]. The eddy currents method consists of the measurement of a material’s response to electromagnetic fields over a specific frequency range [ 9 ]. In railroad track applications, eddy currents probes are located at a

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Abstract  

Until recently, the issue of the thermal gradients within TMDSC samples remained mostly a subject of theory and mathematical models — only the phase lag was subject to experimental verification, as this information is readily available from the analysis software of most instruments. There was no method to verify the transient behaviour and temperature gradients within a sample without making costly and intensive modifications to the equipment. Recently, however, a group of researchers were able to experimentally measure thermal profiles as a function of sample thickness with a high-speed, high-resolution infrared camera mounted on the TMDSC cell. Therefore, this paper is dedicated to comparing the predictions of our three-dimensional model with this newly available data.

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. Infrared thermography: An optical method in heat transfer and fluid flow visualisation, Optics and Lasers in Engineering , Vol. 44, 2006, pp. 261–281. Carlomagno G. M. Infrared

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Abstract  

Thermal analysis (TA) is useful for studying the reaction and thermal properties of free radical cured photopolymers. Starting with reactive liquid monomers, the photocuring reactions are initiated by the interaction of UV radiation with an added photoinitiator to form free radicals. The monomers generally are acrylates or methacrylates. Some of the important characteristics of these systems that can be illustrated by TA methods are: 1) the polymers are heterogeneous with more than one phase present even when only one monomer is involved; 2) because of this heterogeneity they have unusually broad glass transitions; 3) the degree of conversion achieved in many UV cured systems is in the 60–80% range, so that considerable residual monomer is often present; 4) partially cured, vitrified samples contain trapped free radicals that will continue to react slowly; 5) when a partially cured photopolymer is heated above its current T g a reaction exotherm is evident. Some other aspects of photocuring are not easily disclosed by thermal analysis. Studying fast photoreactions by DSC may not give valid kinetic data because the reaction occurs faster than the DSC instrument time constant. Optical methods (IR, Raman) can be used to advantage in such cases. While photocuring resins are usually exposed to light at ambient temperatures, the local temperature in the resin will be quite elevated, resulting in T g values that are much higher than ambient. This has been demonstrated by thermal modeling of the reaction and verified by infrared thermography.

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