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Polymer-based thermal interface materials (TIMs) are having pump out problem and could be resolved for reliable application. Solid-based interface materials have been suggested and reported. The purpose of this paper is suggesting thin film-based TIM to sustain the light-emiting diode (LED) performance and electronic device miniaturization.

Consequently, ZnO thin film at various thicknesses was prepared by chemical vapour deposition (CVD) method and tested their thermal behaviour using thermal transient analysis as solid TIM for high-power LED.

Low value in total thermal resistance (R_th-tot) was observed for ZnO thin film boundary condition than bare Al boundary condition. The measured interface (ZnO thin film) resistance {(R_th-bhs) thermal resistance of the interface layer (thin film) placed between metal core printed circuit board (MCPCB) board and Al substrates} was nearly equal to Ag paste boundary condition and showed low values for ZnO film prepared at 30 min process time measured at 700 mA. The T_J value of LED mounted on ZnO thin film (prepared at 30 min.) coated Al substrates was measured to be 74.8°C. High value in junction temperature difference (ΔT_J) of about 4.7°C was noticed with 30 min processed ZnO thin film when compared with Al boundary condition. Low correlated colour temperature and high luminous flux values of tested LED were also observed with ZnO thin film boundary condition (processed at 30 min) compared with both Al substrate and Ag paste boundary condition.

Overall, 30 min CVD processed ZnO thin film would be an alternative for commercial TIM to achieve efficient thermal management. This will increase the life span of the LED as the proposed material decreases the T_J values.

The coating process is broadly employed in the manufacturing of wallpapers, adhesive tapes, wrapping, protection of fabrics and metals, X-ray and photographic films, beautification, books and magazines, film foils, magnetic records, coated paper, etc.

In this study, an incompressible flow of non-Newtonian fluid is modeled to inspect the rheological behavior of finite coating thickness in the reverse roll coating process. With the assistance of lubrication approximation theory (LAT), the dimensionless form of governing expressions is simplified. Exact solutions for distributions for velocity, flow rate, temperature and pressure gradient attained utilizing perturbation technique and their variation is presented as well as discussed in graphs. Meanwhile, some important factors from an engineering perspective including coating thickness and transition point were calculated mathematically and are displayed in a tabular manner. Also, streamlines are drawn to observe the flow pattern.

Prandtl fluid parameters provide a controlling factor to regulate the flow rate, velocity, coating thickness, and pressure gradient leading to an efficient coating process. Moreover, the Brinkman number and Prandtl fluid parameters significantly improve the temperature distribution.

In the literature, this study fills a gap in the theoretical prediction of coating thickness rheologically influenced by Prandtl fluid in reverse roll coating process.

This study aims to use whiteness (WI) and yellowness indices (YI) that were calculated from the International Commission on Illumination (CIE) color parameter to evaluate the efficiency of some triazole fungicides [propiconazole (C₁₅H₁₇Cl₂N₃O₂) and tebuconazole (C₁₆H₂₂ClN₃O)] to protect wooden artifacts from fungal deterioration.

Archeological wooden samples were collected from some historical Islamic buildings in Cairo, Egypt. Three species of fungi were identified in previous work. Propiconazole and tebuconazole with different concentrations treated the infected wooden samples aged for different periods. WI and YI of studied samples were measured using UV spectrophotometer. Calibration and uncertainty estimation accompanied by color measurement were studied.

Studying the uncertainty sources of diffuse reflection of the standard white tiles revealed that the uncertainty of calibration for both the spectrophotometer and white tiles had the highest contribution. The treated samples with tebuconazole and propiconazole fungicides gave good resistance against fungal deterioration at 0.50% for WI and YI.

This study presents the importance of colorimetry in the conservation field because they are considered one of the most important criteria to evaluate conservation materials. From color measurements and their uncertainties, it became clear that triazole fungicides have good efficiency in the protection of wooden artifacts from fungal deterioration. The value of this study is that propiconazole and tebuconazole fungicides at 0.50% can be applied to archaeological wood that is endangered to improper conditions, especially in the case of high levels of relative humidity.