Optical properties of potassium acid phthalate

1997 ◽  
Vol 12 (5) ◽  
pp. 1262-1267 ◽  
Author(s):  
Davide Comoretto ◽  
Laura Rossi ◽  
Alessandro Borghesi
Keyword(s):  
Optical Properties ◽  
Near Infrared ◽  
Normal Incidence ◽  
Infrared Region ◽  
Visible Range ◽  
Direct Inversion ◽  
Potassium Acid Phthalate ◽  
Absolute Reflectance ◽  
Reflectance Measurements ◽  
Acid Phthalate

Potassium acid phthalate (KAP) crystals are promising as substrates for the growth of highly oriented films of conjugated polymers with exceedingly high and fast nonlinear optical response. We report the KAP optical properties (real and imaginary parts of the refractive index ñ = n + ik) in the near infrared and visible range deduced by ellipsometric measurements and direct inversion of transmittance and near-normal incidence absolute reflectance measurements. In the infrared region n was also deduced by the interference fringes.

scholarly journals Combination of Zinc Oxide and Antimony Doped Tin Oxide Nanocoatings for Glazing Application

Coatings ◽  
2018 ◽  
Vol 8 (7) ◽  
pp. 248 ◽  
Author(s):  
Benjamin Schumm ◽  
Thomas Abendroth ◽  
Saleh A. Alajlan ◽  
Ahmed M. Almogbel ◽  
Holger Althues ◽  
...  
Keyword(s):  
Thin Films ◽  
Zinc Oxide ◽  
Optical Properties ◽  
Tin Oxide ◽  
Near Infrared ◽  
Glass Production ◽  
Float Glass ◽  
Building Envelope ◽  
Visible Range ◽  
Production Processes

Multilayered nanocoatings allow outstanding properties with broad potential for glazing applications. Here, we report on the development of a multilayer nanocoating for zinc oxide (ZnO) and antimony doped tin oxide (ATO). The combination of ZnO and ATO thin films with their promising optical properties is a cost-efficient alternative for the production of energy-efficient glazing. It is an effective modification of the building envelope to reduce current high domestic demand of electrical power for air conditioning, especially in hot climates like Saudi Arabia. In this paper, we report the development of a nanocoating based on the combination of ZnO and ATO. Principle material and film investigations were carried out on lab-scale by dip coating with chemical solution deposition (CSD), while with regard to production processes, chemical vapor deposition (CVD) processes were evaluated in a second stage of the film development. It was found that with both processes, high-quality thin films and multilayer coatings with outstanding optical properties can be prepared. While keeping the optical transmission in the visible range at around 80%, only 10% of the NIR (near infrared) and below 1% of UV (ultraviolet) light passes these coatings. However, in contrast to CSD, the CVD process allows a free combination of the multilayer film sequence, which is of high relevance for production processes. Furthermore, it can be potentially integrated in float glass production lines.

scholarly journals Optical properties of spray pyrolysis deposited Cds:Al thin films

2015 ◽  
Vol 39 (1) ◽  
pp. 25-30 ◽  
Author(s):  
A Hasnat Rubel ◽  
J Podder
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Spray Pyrolysis ◽  
Near Infrared ◽  
Visible Region ◽  
Cadmium Sulphide ◽  
Infrared Region ◽  
Photo Detectors ◽  
Direct Energy ◽  
Academy Of Sciences

Aluminium doped cadmium sulphide thin films were prepared on glass substrate using aqueous solution of cadmium sulphide and thiourea salts by spray pyrolysis deposition (SPD) technique. Its optical properties were analyzed as a function of doping concentration. The direct energy band-gap of Al-doped CdS films was estimated in the range of 2.25 to 2.48 eV. The optical spectra of Cd1-xAlxS ternary system exhibit high absorption near visible region and transmission throughout the near-infrared region (600 - 1200 nm). Thus so obtained hetero-junction films are suitable for fabrication of photo detectors, solar cells and other optoelectronics devices.Journal of Bangladesh Academy of Sciences, Vol. 39, No. 1, 25-30, 2015

EFFECT OF L-METHIONINE ON THE OPTICAL PROPERTIES OF POTASSIUM ACID PHTHALATE

2007 ◽  
Vol 21 (30) ◽  
pp. 2089-2094
Author(s):  
N. A. PAREY ◽  
M. A. SHAH
Keyword(s):  
Optical Properties ◽  
Slow Cooling ◽  
X Ray ◽  
Cooling Method ◽  
Bulk Single Crystals ◽  
Ft Ir ◽  
Ir Analysis ◽  
Potassium Acid Phthalate ◽  
Parameter Values ◽  
Acid Phthalate

The effect of L-methionine doping on the optical properties of potassium acid phthalate have been studied. Bulk single crystals of L-methionine-doped potassium acid phthalate (LMDKAP) were grown by a slow cooling method using a constant temperature bath. X-ray powder diffraction study has revealed the significant variation in the cell parameter values and the shift in peak positions, which confirms the presence of dopant in the sample. The UV-VIS cut off wavelength of LMDKAP was found to be 300 nm and it is slightly less than KAP. The presence of functional groups present in LMDKAP were confirmed through FT-IR analysis.

The Electronic Spectra of Hg–In Alloys

1973 ◽  
Vol 51 (9) ◽  
pp. 894-913 ◽  
Author(s):  
Barry Siskind ◽  
James Boiani ◽  
Stuart A. Rice
Keyword(s):  
Magnetic Susceptibility ◽  
Optical Properties ◽  
Density Of States ◽  
Normal Incidence ◽  
Electron Excitation ◽  
Concentration Gradients ◽  
Magnetic Susceptibility Data ◽  
Long Wavelength ◽  
Susceptibility Data ◽  
Reflectance Measurements

We have made reflectance measurements on liquid Hg–In alloys at near-normal incidence from 0.14 to 4.0 μm. After describing our apparatus, the experimental results, and the treatment of our data we make the following interpretations:(a) that the peak in ε2 at about 8.5 eV consists of a superposition of a d-electron excitation and a plasma (or Hopfield) resonance;(b) that the peak in ε2 at about 5.8 eV is associated with a peak in the density of states and is a consequence of a scattering resonance in the In ion-core pseudopotential;(c) that concentration gradients and a diffuse transition zone at the surface of the liquid alloy may have a significant effect on the optical properties, not only in ellipsometric experiments but also in reflectance experiments;(d) that an excess reflectance which we find at our long-wavelength limit can be explained in terms of an anomalously large density of states at the Fermi level and that this is consistent with available Hall coefficient and magnetic susceptibility data.

scholarly journals Optical investigation of bovine grey and white matters in visible and near-infrared ranges

2021 ◽  
Vol 27 (1) ◽  
pp. 99-107
Author(s):  
Ali Shahin ◽  
Wesam Bachir ◽  
Moustafa Sayem El-Daher
Keyword(s):  
Optical Properties ◽  
Absorption Coefficient ◽  
Wavelength Range ◽  
Grey Matter ◽  
Near Infrared ◽  
Biological Tissues ◽  
Integrating Sphere ◽  
Visible Range ◽  
Optical Investigation

Abstract Introduction: Due to enormous interests for laser in medicine and biology, optical properties characterization of different tissue have be affecting in development processes. In addition, the optical properties of biological tissues could be influenced by storage methods. Thus, optical properties of bovine white and grey tissues preserved by formalin have been characterized over a wide wavelength spectrum varied between 440 nm and 1000 nm. Materials and Methods: To that end, a single integrating sphere system was assembled for spectroscopic characterization and an inverse adding-doubling algorithm was used to retrieve optical coefficients, i.e. reduced scattering and absorption coefficients. Results: White matter has shown a strong scattering property in comparison to grey matter. On the other hand, the grey matter has absorbed light extensively. In comparison, the reduced scattering profile for both tissue types turned out to be consistent with prior works that characterized optical coefficients in vivo. On the contrary, absorption coefficient behavior has a different feature. Conclusion: Formalin could change the tissue’s optical properties because of the alteration of tissue’s structure and components. The absence of hemoglobin that seeps out due to the use of a formalin could reduce the absorption coefficient over the visible range. Both the water replacement by formalin could reduce the refractive index of a stored tissue and the absence of hemoglobin that scatters light over the presented wavelength range should diminish the reduced scattering coefficients over that wavelength range.

scholarly journals Photometric Observations of Aerosol Optical Properties and Emission Flux Rates of Stromboli Volcano Plume during the PEACETIME Campaign

2021 ◽  
Vol 13 (19) ◽  
pp. 4016
Author(s):  
Pasquale Sellitto ◽  
Giuseppe Salerno ◽  
Jean-François Doussin ◽  
Sylvain Triquet ◽  
François Dulac ◽  
...  
Keyword(s):  
Optical Properties ◽  
Near Infrared ◽  
Visible Range ◽  
Infrared Range ◽  
Emission Flux ◽  
Stromboli Volcano ◽  
Aerosol Emission ◽  
Photometric Observations ◽  
Sulphate Aerosols ◽  
Aerosol Emissions

The characterisation of aerosol emissions from volcanoes is a crucial step towards the assessment of their importance for regional air quality and regional-to-global climate. In this paper we present, for the first time, the characterisation of aerosol emissions of the Stromboli volcano, in terms of their optical properties and emission flux rates, carried out during the PEACETIME oceanographic campaign. Using sun-photometric observations realised during a near-ideal full plume crossing, a plume-isolated aerosol optical depth of 0.07–0.08 in the shorter-wavelength visible range, decreasing to about 0.02 in the near infrared range, was found. An Ångström exponent of 1.40 ± 0.40 was also derived. This value may suggest the dominant presence of sulphate aerosols with a minor presence of ash. During the crossing, two separate plume sections were identified, one possibly slightly affected by ash coming from a mild explosion, and the other more likely composed of pure sulphate aerosols. Exploiting the full crossing scan of the plume, an aerosol emission flux rate of 9–13 kg/s was estimated. This value was 50% larger than for typical passively degassing volcanoes, thus pointing to the importance of mild explosions for aerosol emissions in the atmosphere.

scholarly journals First principles DFT calculations of the optical properties of A4BX6 group crystals

2021 ◽  
Vol 22 (1) ◽  
pp. 117-122
Author(s):  
H. Ilchuk ◽  
M. Solovyov ◽  
I. Lopatynskyi ◽  
F. Honchar ◽  
F. Tsyupko
Keyword(s):  
Optical Properties ◽  
First Principles ◽  
Energy Band ◽  
Density Functional ◽  
Near Infrared ◽  
Infrared Region ◽  
Energy Structure ◽  
Generalized Gradient ◽  
Reflection Index ◽  
Functional Theory

The results of investigating of the electron band energy structure and optical properties of A4BX6 (Tl4HgI6 and Tl4CdI6) group crystals are presented. The energy band structures of Tl4HgI6 and Tl4CdI6 crystals are calculated from the first principles within generalized gradient approximation (GGA). The band structure and reflection index were calculated using a pseudopotential method in the framework of density functional theory. Optical absorption edge in Tl4HgI6 and Tl4CdI6 is formed by direct optical transitions. The spectral dependence of the reflection index was calculated on the basis of the energy band results with using the Kramers–Kronig method. The spectra show pronounced anisotropy in E||a(b) and E||c polarizations. It was found the anomalous by large values of the birefringence (Δn > 0.18 for Tl4HgI6 and Δn > 0.03 for Tl4CdI6) in the visible and near infrared region.

scholarly journals Experimental constraints on the ordinary chondrite shock darkening caused by asteroid collisions

2020 ◽  
Vol 639 ◽  
pp. A146 ◽  
Author(s):  
T. Kohout ◽  
E. V. Petrova ◽  
G. A. Yakovlev ◽  
V. I. Grokhovsky ◽  
A. Penttilä ◽  
...  
Keyword(s):  
Optical Properties ◽  
Near Infrared ◽  
Infrared Region ◽  
Shock Pressure ◽  
Ordinary Chondrite ◽  
Second Stage ◽  
Shock Experiment ◽  
Induced Changes ◽  
Spherical Shock ◽  
Characteristic Pressure

Context. Shock-induced changes in ordinary chondrite meteorites related to impacts or planetary collisions are known to be capable of altering their optical properties. Thus, one can hypothesize that a significant portion of the ordinary chondrite material may be hidden within the observed dark C/X asteroid population. Aims. The exact pressure-temperature conditions of the shock-induced darkening are not well constrained. Thus, we experimentally investigate the gradual changes in the chondrite material optical properties as a function of the shock pressure. Methods. A spherical shock experiment with Chelyabinsk LL5 was performed in order to study the changes in its optical properties. The spherical shock experiment geometry allows for a gradual increase of shock pressure from ~15 GPa at a rim toward hundreds of gigapascals in the center. Results. Four distinct zones were observed with an increasing shock load. The optical changes are minimal up to ~50 GPa. In the region of ~50–60 GPa, shock darkening occurs due to the troilite melt infusion into silicates. This process abruptly ceases at pressures of ~60 GPa due to an onset of silicate melting. At pressures higher than ~150 GPa, recrystallization occurs and is associated with a second-stage shock darkening due to fine troilite-metal eutectic grains. The shock darkening affects the ultraviolet, visible, and near-infrared region while changes to the MIR spectrum are minimal. Conclusions. Shock darkening is caused by two distinct mechanisms with characteristic pressure regions, which are separated by an interval where the darkening ceases. This implies a reduced amount of shock-darkened material produced during the asteroid collisions.

scholarly journals SARS-CoV-2 Detection using Colorimetric Plasmonic Sensors: A Proof-of-Concept Computational Study

2021 ◽  
Author(s):  
Somen Baidya ◽  
Ahmed M Hassan
Keyword(s):  
Gold Nanoparticles ◽  
Outer Surface ◽  
Near Infrared ◽  
Computational Study ◽  
Visible Spectrum ◽  
Resonance Wavelength ◽  
Infrared Region ◽  
Molecular Techniques ◽  
Visible Range ◽  
Broadband Absorption

Traditional molecular techniques for SARS-CoV-2 viral detection are time-consuming and can exhibit a high probability of false negatives. In this work, <a>we present a computational study of SARS-CoV-2 detection using plasmonic gold nanoparticles</a>. The resonance wavelength of a SARS-CoV-2 virus was recently estimated to be in the near-infrared region. By engineering gold nanospheres to specifically bind with the outer surface of the SARS-CoV-2 virus, the resonance frequency can be shifted to the visible range (380 nm – 700 nm). Moreover, we show that broadband absorption will emerge in the visible spectrum when the virus is partially covered with gold nanoparticles at a specific coverage percentage. This broadband absorption can be used to guide the development of an efficient and accurate colorimetric plasmon sensor for COVID-19 detection. Our observation also suggests that this technique is unaffected by the number of protein spikes present on the virus outer surface, hence can pave a potential path for a diagnostic tool independent on the number of protein spikes.

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