UV-visible-near IR reflectance spectrophotometry in a museum environment

Native fluorescence, or autofluorescence (AF), consists in the emission of light in the UV-visible, near-IR spectral range when biological substrates are excited with light at suitable wavelength. This is a well-known phenomenon, and the strict relationship of many endogenous fluorophores with morphofunctional properties of the living systems, influencing their AF emission features, offers an extremely powerful resource for directly monitoring the biological substrate condition. Starting from the last century, the technological progresses in microscopy and spectrofluorometry were convoying attention of the scientific community to this phenomenon. In the future, the interest in the autofluorescence will certainly continue. Current instrumentation and analytical procedures will likely be overcome by the unceasing progress in new devices for AF detection and data interpretation, while a progress is expected in the search and characterization of endogenous fluorophores and their roles as intrinsic biomarkers.

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Characterization of conichalcite by SEM, FTIR, Raman and electronic reflectance spectroscopy

Mineralogical Magazine ◽

10.1180/0026461056920243 ◽

2005 ◽

Vol 69 (2) ◽

pp. 155-167 ◽

Cited By ~ 20

Author(s):

B. J. Reddy ◽

R. L. Frost ◽

W. N. Martens

Keyword(s):

Near Infrared ◽

Adsorbed Water ◽

Reflectance Spectroscopy ◽

Sem Images ◽

X Ray ◽

Near Ir ◽

Ir Reflectance ◽

Yavapai County ◽

Ir Bands

AbstractThe mineral conichalcite from the western part of Bagdad mine, Bagdad, Eureka District, Yavapai County, Arizona, USA has been characterized by electronic, near-infrared (NIR), Raman and infrared (IR) spectroscopy. Scanning electron microscopy (SEM) images show that the mineral consists of bundles of fibres. Calculations based on the results of the energy dispersive X-ray analyses on a stoichiometric basis show the substitution of arsenate by 12 wt.% of phosphate in the mineral. Raman and IR bands are assigned in terms of the fundamental modes of AsO43− and PO43− molecules and are related to the mineral structure. Near-IR reflectance spectroscopy shows the presence of adsorbed water and hydroxyl units in the mineral. The Cu(II) coordination polyhedron in conichalcite can have at best pseudo-tetragonal geometry. The crystal field and tetragonal field parameters of the Cu(II) complex were calculated and found to agree well with the values reported for known tetragonal distortion octahedral complexes.

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Near-Ir Resonance Raman and Uv-Visible Absorption Kinetic Spectroscopy of Optogenetic Archaerhodopsin Neuronal Silencers: Effects of Membrane Potential

Biophysical Journal ◽

10.1016/j.bpj.2012.11.3753 ◽

2013 ◽

Vol 104 (2) ◽

pp. 680a

Author(s):

John I. Ogren ◽

Erica C. Saint Clair ◽

Sergey Mamaev ◽

Daniel Russano ◽

Joel M. Kralj ◽

...

Keyword(s):

Membrane Potential ◽

Resonance Raman ◽

Visible Absorption ◽

Kinetic Spectroscopy ◽

Near Ir ◽

Absorption Kinetic ◽

Uv Visible

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On the Radiation Stability of BaSO4 Pigment Modified with SiO2 Nanoparticles and Applied for Spacecraft Thermal Control Coatings

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.386.277 ◽

2018 ◽

Vol 386 ◽

pp. 277-282 ◽

Cited By ~ 1

Author(s):

Mikhail M. Mikhailov ◽

Vitaly V. Neshchimenko ◽

Semyon A. Yuryev ◽

Anatoly V. Grigorevsky ◽

Alexey A. Lovitskiy ◽

...

Keyword(s):

Thermal Control ◽

Radiation Stability ◽

Maximum Effect ◽

Nanoparticle Concentration ◽

Absorption Bands ◽

Near Ir ◽

Uv Visible ◽

Thermal Control Coatings ◽

Spacecraft Thermal Control ◽

High Temperature Modification

The authors investigated the effect of a high-temperature modification with SiO2 nanoparticles on the optical properties and radiation stability of BaSO4 powders. The modification leads to insignificant alteration in the reflecting capacity within the UV, visible, and near-IR spectral regions. Appending SiO2 nanoparticles with a concentration of up to 10 wt.% results in the increasing radiation stability of BaSO4 powders. The maximum effect was obtained due to the decreasing intensity of the absorption bands at 270-280, 375-395, 440-460, 500-600, 700, and 950 nm at a nanoparticle concentration of 3 wt.%.

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