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Contribution of the Refractive Index Fluctuations to the Length Noise in Displacement Interferometry

] Edlen, B. (1966) The refractive index of air. Metrologia, 2 (2), 71-80. [13] Birch, K.P., Downs, M.J. (1993). An updated edlen equation for the refractive-index of air. Metrologia, 30 (3), 155-162. [14] Ciddor, P.E. (1996). Refractive index of air: New equations for the visible and near infrared. Applied Optics, 35 (9), 1566-1573. [15] Birch, K.P., Downs, M.J. (1994). Correction to the updated edlen equation for the refractive-index of air. Metrologia, 31 (4), 315-316. [16] Lazar, J., Cip, O., Cizek, M

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Study of the refractive index of gasoline+alcohol pseudo-binary mixtures

Procedia 95 (2016) 330-336. https://doi.org/10.1016/j.egypro.2016.09.017 [10]. I. Nita, S. Geacai, A. Neagu, E. Geacai, Estimation of the refractive index of diesel fuel+biodiesel blends, Ovidius University Annals of Chemistry 24 (2013) 24-26. https://doi.org/10.2478/auoc-2013-0005 [11]. B.V. Sakhnevitch, M.V. Kirgina, N.V. Chekancev, E.D. Ivanchina, A.A. Syskina, Complex System for Gasoline Blending Maintenance, Procedia Chemistry 10 (2014) 289-296. https://doi.org/10.1016/j.proche.2014.10.049 [12]. V.F. Nikolaev, I

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Estimation of the refractive index of diesel fuel+biodiesel blends

Abstract

For now, biodiesel is the commonly accepted biofuel as a substitute for diesel fuel in internal combustion engines. Diesel fuel blends with up to 20% biodiesel can be used in diesel engines without any modification. A lot of studies regarding diesel fuel+biodiesel blends properties are presented in the literature. Some of the important properties of diesel fuel+biodiesel blends can be evaluated from other blends properties. For example, density and viscosity of biodiesel blends can be predicted based on blend refractive index. More than that, refractive index can be used as a reliable physical property to predict transesterification reaction progress. As a result, the refractive index of diesel fuel+biodiesel blends is important in order to characterize these blends or to monitor the evolution of transesterification process of vegetable oils or animal fats. The refractive index of diesel fuel+biodiesel blends can be experimentally determined or evaluated based on refractive indices of diesel fuel and biodiesel. The aim of this study was to estimate the accuracy of refractive index of diesel fuel +biodiesel blends calculation, using models initially proposed to evaluate the refractive index of a binary liquid mixture. It was shown that the refractive index of diesel fuel+biodiesel blends can be accurately predicted from refractive indices of the components of the blend. Wiener, Heller and Edward equations can be recommended to predict with a great accuracy the refractive index of diesel fuel+biodiesel blends.

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About complex refractive index of black Si

Abstract

The paper deals with the complex refractive index in the IR light region of two types of samples (i) as prepared black silicon, and (ii) thermally oxidized black silicon (BSi) nano-crystalline specimens produced both by the surface structure chemical transfer method using catalytic Ag evaporated spots (as prepared sample) and by the catalytic Pt catalytic mesh (thermally oxidized sample). We present, compare, and discuss the values of the IR complex refractive index obtained by calculation using the Kramers-Krönig transformation. Results indicate that small differences between optical properties of as prepared black Si and thermally oxidized BSi are given by: (i) – oxidation procedure, (ii) – thickness of the formed black Si layer, mainly, not by utilization of different catalytic metals, and by iii) the different thickness. Contamination of the surface by different catalytic metals contributes almost equally to the calculated values of the corresponding complex refractive index.

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Measurement of Low Concentration of Nanosized Objects Suspended in a Liquid Medium

, Bulgaria, 91–92. 4. Vilitis, O., Merkulovs, D., & Kozlovs, V. (2017). Measurement of low concentration of nanosized objects in bioliquids by means of refractometric methods. In Proceedings of the 13th International Conference on Medical Physics “Medical physics in the Baltic states” , Kaunas, Lithuania (pp. 132–136). 5. Vilitis, O., Merkulov, D., & Kozlov, V. (2003). Method and refractometer for measuring refractive index of liquids. Patent LV13294 B. 6. Vilitis, O., & Merkulov, D. (2006). Method for detecting optical image of the light beam in

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Thin SixNyCz films deposited from hexamethyldisilazane by RF PECVD technique for optical filter applications

Abstract

This work initiates a series of reports aimed at a construction of rugate optical filters based on silicon rich materials of alternating gradients of refractive index n with the help of plasma enhanced chemical vapor deposition (PECVD) technique, The idea is to start deposition of high refractive index SixNy type of material using hexamethyldisilazane (HMDSN) vapor and nitrogen rich atmosphere, and then to gradually replace nitrogen with oxygen in that atmosphere in order to lower n down to a minimum characteristic of SixOy type of material. A return to initial gas composition should increase the index back to its maximum. In the present work, thin SixNyCz films were synthesized from a mixture of HMDSN vapor with gaseous NH3 and N2. The effect of NH3/N2 ratio on the coating morphology, its elemental composition, chemical bonding and optical properties was studied using scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, ultra-violet absorption spectroscopy and variable angle spectroscopic ellipsometry. The results show that films of the highest index of refraction and the lowest extinction coefficient have been deposited from the gas mixture containing 90 % of ammonia. These coatings are also characterized by the lowest carbon and the highest nitrogen contents.

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The structure and optical properties of lead-free transparent KNLTN-La0.01 ceramics prepared by conventional sintering technique

Abstract

(Na0.52K0.44Li0.04)0.97La0.01Ta0.20Nb0.80O3 (KNLTN-La0.01) lead-free subtransparent ceramics was prepared by a conventional sintering technique. The structure and the optical properties of the ceramics were investigated. The room temperature crystallographic indexing revealed the ABO3 perovskite type, tetragonal phase and P4mm point group in the ceramics. The surface and fractured surface SEM micrographs showed a dense microstructure with few micropores in KNLTN-La0.01 ceramics, which was obviously better than for the pure KNLTN ceramics. The refractive indexes of the films were investigated by an ellipsometer and the results show that the KNLTN-La0.01 subtransparent ceramics reveals significant wavelength dependent dispersion. The refractive index ranges from 2.14 to 2.06 with the wavelength increase from 380 nm to 900 nm. The dispersive behavior was analyzed by three parameters of Cauchy dispersion model and the values of the parameters A, B and C are 2.0610±0.0005, 0.0054±0.0003 and 0.00069±0.00004, respectively.

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Synthesis and investigation of nonlinear optical properties of Para Red: Z-scan technique and quantum mechanical calculations

Abstract

In this study, we present a systematic study of linear and nonlinear optical properties of Para Red with the aim of Z-scan technique and quantum mechanical calculations. The Z-scan experiments were performed using a 532 nm Nd: YAG (SHG) CW laser beam. Para Red exhibited a strong nonlinear refractive index, nonlinear absorption coefficient and third-order nonlinear susceptibility 3.487 × 10−6 cm2/W, 2.341 × 10−1cm/W and 2.157 × 10−4 esu, respectively. Also, quantum chemical analysis was used for the calculation of the dipole moment μ, dipole polarizability α, anisotropy of polarizability Δα and molecular hyperpolarizabilities (β,γ). The results revealed that Para Red has large first and second hyperpolarizabilities. However, from the obtained results, it was found that Para Red can be a promising material for applications in the development of non-linear optical materials.

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Comparison of a Multiple Regression Model and a two-Regime Model of a Vertical Refraction/ Porovnanie Viacnásobného Regresného Modelu A Dvojrežimového Modelu Vertikálnej Refrakcie

. [19] WEISS, Alexandra I - HENNES, Maria - ROTACH, Mathias W. 2001. Derivation Of Refractive Index And Temperature Gradients From Optical Scintillometry To Correct Atmospherically Induced Errors For Highly Precise Geodetic Measurements. In: Surveys in Geophysics. 2001, vol. 22, issue. 5-6, pp. 589-596.

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Optical properties of zinc titanate perovskite prepared by reactive RF sputtering

Abstract

In this paper we report results from optical transmittance spectroscopy complemented with data on structure from XRD measurements to determine optical properties of a series of ZnTiO3 perovskite thin films deposited on glass by reactive magnetron co-sputtering. The members of the series differ by the titanium content that was revealed as an origin of the changes not only in structure but also in dispersive optical properties. Low porosity has been discovered and calculated using the Bruggeman effective medium approximation. An apparent blue-shift of the optical band gap energies with increasing titanium content was observed. The observed band gap engineering is a good prospective for eg optoelectronic and photocatalytic applications of ZnTiO3.

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