Search results for "Transmitted light"
showing 5 items of 5 documents
New results in ancient Maya rituals researches: The study of human painted bones fragments from Calakmul archaeological site (Mexico)
2020
Abstract The funeral chambers of the ancient city of Calakmul (Mexico) and the individuals who were buried in them have brought in recent decades new knowledge about the beliefs and funeral customs of the pre-Hispanic Maya. Tombs and bodies were prepared as part of the rituals that should favor the return of ch'ulel to the Underworld, known as Xibalba by the ancient Maya. The ch'ulel is one of the two anemic entities that inhabit the individual, equivalent to our concept of the soul. Bodies preparation included coloured scented body ointments application, with a deep symbolic connotation and probably also a conservative purpose. The aim of this research was to characterize pigments and bind…
The measurement of light transmission through an irradiated fluidised bed
1983
Abstract The transmission of light through an irradiated fluidised bed with vertical flat walls containing catalytic particles has been experimentally studied. The amount of light transmitted through the reactor was measured at different levels by a photocell. The experimental variables studied included: (i) gas flow rate, varying from 2 to more than 10 times that required for minimum fluidisation; (ii) mean particle size, ranging from 0.138 to 0.275 mm; and (iii) internal bed thickness from 2.1 to 4.9 mm. The effect of the reflectance of the particles was also examined. Results show that the amount of light transmitted through a flat fluidised bed is low. The average transmitted light has …
Spatial coherence properties of a multiple aperture system an analysis based on the Walsh functions
1997
Analysis of the spatial coherence of the light transmitted by an optical device composed of a periodical array of identical apertures is developed by employing an approach based on the properties of the binary Walsh functions. The successive interactions between each aperture, and the mutual intensity characterizing the coherence state of the transmitted light, can be adequately explained through the behaviour of the Walsh-Hadamard spectrum associated with the intensity distribution resulting from the far-field propagated light at the output of the aperture array.
Low-cost high-haze films based on ZnO nanorods for light scattering in thin c-Si solar cells
2015
Light scattering from ZnO nanorods (NR) is investigated, modeled, and applied to a solar cell. ZnO NR (120-1300 nm long, 280-60 nm large), grown by low-cost chemical bath deposition at 90 degrees C, exhibit diffused-to-total transmitted light as high as 70% and 30% in the 400 and 1000 nm wavelength range, respectively. Data and scattering simulation show that ZnO NR length plays a crucial role in light diffusion effect. A transparent ZnO NR film grown on glass and placed on top of a 1 mu m thick c-Si solar cell is shown to enhance the light-current conversion efficiency for wavelengths longer than 600 nm. (C) 2015 AIP Publishing LLC.
Using the fibre structure of paper to determine authenticity of the documents: analysis of transmitted light images of stamps and banknotes.
2014
A novel method is presented for distinguishing postal stamp forgeries and counterfeit banknotes from genuine samples. The method is based on analyzing differences in paper fibre networks. The main tool is a curvelet-based algorithm for measuring overall fibre orientation distribution and quantifying anisotropy. Using a couple of more appropriate parameters makes it possible to distinguish forgeries from genuine originals as concentrated point clouds in two- or three-dimensional parameter space.