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Hyperspectral Pigment Analysis of Cultural Heritage Artifacts Using the Opaque Form of Kubelka-Munk Theory [PDF]

Proc. SPIE 10986, Algorithms, Technologies, and Applications for Multispectral and Hyperspectral Imagery XXV, 1098611, 2019, 2021
Kubelka-Munk (K-M) theory has been successfully used to estimate pigment concentrations in the pigment mixtures of modern paintings in spectral imagery. In this study the single-constant K-M theory has been utilized for the classification of green pigments in the Selden Map of China, a navigational map of the South China Sea likely created in the early
arxiv   +1 more source

Cellulose Photonic Pigments [PDF]

Nature Communications 2022, 2021
When pursuing sustainable approaches to fabricate photonic structures, nature can be used as a source of inspiration for both the nanoarchitecture and the constituent materials. Although several biomaterials have been promised as suitable candidates for photonic materials and pigments, their fabrication processes have been limited to the small to ...
arxiv   +1 more source

Optimal number of pigments in photosynthetic complexes [PDF]

New J. Phys. 14, 093017 (2012), 2012
We study excitation energy transfer in a simple model of photosynthetic complex. The model, described by Lindblad equation, consists of pigments interacting via dipole-dipole interaction. Overlapping of pigments induces an on-site energy disorder, providing a mechanism for blocking the excitation transfer.
arxiv   +1 more source

The peak absorbance wavelength of photosynthetic pigments around other stars from spectral optimization [PDF]

Front. Astron. Space Sci., July 8, 2021, 2021
In the search for life on other planets, the presence of photosynthetic vegetation may be detectable from the colors of light it reflects. On the modern Earth, this spectral reflectance is characterized by an increase in reflectance between the red and near-infrared wavelengths, a "red edge".
arxiv   +1 more source

Nonphotosynthetic Pigments as Potential Biosignatures [PDF]

Astrobiology 15(5): 341-361 (2015), 2015
Previous work on possible surface reflectance biosignatures for Earth-like planets has typically focused on analogues to spectral features produced by photosynthetic organisms on Earth, such as the vegetation red edge. Although oxygenic photosynthesis, facilitated by pigments evolved to capture photons, is the dominant metabolism on our planet ...
arxiv   +1 more source

Can Deep Learning Assist Automatic Identification of Layered Pigments From XRF Data? [PDF]

arXiv, 2022
X-ray fluorescence spectroscopy (XRF) plays an important role for elemental analysis in a wide range of scientific fields, especially in cultural heritage. XRF imaging, which uses a raster scan to acquire spectra across artworks, provides the opportunity for spatial analysis of pigment distributions based on their elemental composition.
arxiv  

Efficient structural color from pigment-loaded nanostructures [PDF]

arXiv, 2023
Color can originate from wavelength-dependence in the absorption of pigments or the scattering of nanostructures. While synthetic colors are dominated by the former, vivid structural colors found in nature have inspired much research on the latter. However, many of the most vibrant colors in nature involve the interactions of structure and pigment ...
arxiv  

Synthesis and acid resistance of maya blue pigment [PDF]

Archaeometry 48, 1 (2006) 115-130, 2012
Maya blue is an organo-clay artificial pigment composed of indigo and palygorskite. It was invented and frequently used in Mesoamerica in ancient times (eighth to 16th centuries). We analyse in this paper one of the characteristics of Maya blue that has attracted the attention of scientists since its rediscovery in 1931: its high stability against ...
arxiv   +1 more source

A non-linear irreversible thermodynamic perspective on organic pigment proliferation and biological evolution [PDF]

J. Phys.: Conf. Ser. 475 012010, 2013, 2013
The most important thermodynamic work performed by life today is the dissipation of the solar photon flux into heat through organic pigments in water. From this thermodynamic perspective, biological evolution is thus just the dispersal of organic pigments and water throughout Earth's surface, while adjusting the gases of Earth's atmosphere to allow the
arxiv   +1 more source

Nanoscale cuticle mass density variations influenced by pigmentation in butterfly wing scales [PDF]

arXiv, 2023
How pigment distribution influences the cuticle density within a microscopic butterfly wing scale, and how both impact final reflected color remains unknown. We used ptychographic X-ray computed tomography to quantitatively determine, at nanoscale resolutions, the three-dimensional mass density of scales with pigmentation differences.
arxiv