Intra-seasonal oscfffations of radio refractive index during southwest monsoon over India

The study deals with the spatial and temporal variations of intra-seasonal oscillations in radio refractive index during southwest monsoon season over India and islands over Indian seas. Average daily radio refractive index data from 1 June to 30 September and that of the individual years for the period 1969-1986 were subjected to harmonic analysis to investigate the contributions of various periodicities in monsoon radio refractive index. The inter-annual variability of various intra-seasonal oscillations have been studied for each 5° latitudinal strip from 50 oN to 30° N with the help of variance explained by various frequency modes for different years. Variance explained by 30-60 day and 10-20 day modes were studied in relation to monsoon performance. The northward and eastward propagation of30.60 day mod~ was noticed. The 10.20 day mode and seasonal mode dominate at latitudinal belts 5°N.10oN and 25°N-30°N respectively. Between 10°N and 25°N, both 30-60 day and 10-20 day modes occur.

Effect of Aging with Pollution on the Complex Refractive Index of Pure Submicron Clay Particles

Modelling the optical and radiative properties of atmospheric particles is governed by one of the key input parameters, i.e., the refractive index of aerosols. Availability of the region-specific refractive index data of aerosols is a major challenge for the atmospheric community. The refractive index of aerosols is a function of their physico-chemical properties. Uncertainty in the computation of the spectral refractive indices of aerosols leads to erroneous assessment of their optical and radiative properties. In the present work, the refractive indices of pure clay (kaolinite, illite) and polluted clay with anthropogenic hematite, AH (0.10 to 1.48%) submicron particles have been computed for the wavelength range of 0.38 to 1.2 µm. Anthropogenic hematite enhanced the overall absorption in the UV and visible range with maximum absorption at lower wavelengths (less than 0.55 µm).

The Analysis of Light Intensity Transmission Coefficient Through Plastic Fibers for the Design of Closed Room Lighting without Electricity

The phenomenon of total internal reflection can be used to guide the light to be transmitted from one place to another, it is applied to the guiding principle of light in fiber optics. A fiber rope made of clear plastic material with a uniform refractive index, when one end fired a beam of light then the light will be forwarded along the strap so that out at the other end. This principle can be applied as a lighting source in a closed room by passing light from the outdoors by using plastic fiber, so it doesn’t need the electricity. In this study, theoretical analysis of the percentage of the intensity of light transmitted by the fiber plastic succeed as a function of the refractive index and determine the transmission coefficient for some plastic seeds are eligible to be used as a plastic fiber light successor. From the results of deriving the equation, the light transmission coefficient of plastic is and the terms of plastic seeds that can be used as a plastic fiber are having a refractive index . Based on refractive index data from profesionalplastics, the maximum transmission coefficient value for Ethylene Tetrafluoro Ethylene Copolymer is 82.23% and the minimum transmission value of Fluorinated Ethylene Propylene Copolymer is 55.99%.

Optical Properties, Excess Volume Prediction from Refractive Index and Intermolecular Interactions in Dibutylamine + Isomeric Butanol

The alkyl or alkanol amines are widely used as absorbent for CO2 capture owing to interaction between amines and CO2. In order to increase the CO2 loading in amine based absorbents, blending of amine with alkanol may be one option. As thermophysical properties of of utmost importance in designing, in present work, the refractive index of dibutylamine (DBA) and isomeric butanol as well as their binary mixtures at 298.15 K to 308.15 K were measured. The Δn are found positive for DBA + isomeric butanol mixtures. The Δn values were correlated with Redlich-Kister polynomial. The refractive index data were also predicted by various correlations and results were expressed in terms of standard deviation. The Δn values were also employed to calculate the excess molar volume of the present binary mixtures. Further Δn data analysed in terms of intermolecular interaction among DBA (1) + isomeric butanol (2) mixtures.

Bandgap and refractive index estimates of InAlN and related nitrides across their full composition ranges

III-Nitride bandgap and refractive index data are of direct relevance for the design of (In, Ga, Al)N-based photonic and electronic devices. The bandgaps and bandgap bowing parameters of III-nitrides across the full composition range are reviewed with a special emphasis on InxAl1−xN, where less consensus was reached in the literature previously. Considering the available InAlN data, including those recently reported for low indium contents, empirical formulae for InAlN bandgap and bandgap bowing parameter are proposed. Applying the generalised bandgap data, the refractive index dispersion data available in the literature for III-N alloys is fitted using the Adachi model. For this purpose, a formalism involving a parabolic dependence of the Adachi parameters on the dimensionless bandgap $${\xi }_{{E}_{\mathrm{g}}}=\left({E}_{\mathrm{g}, {\mathrm{A}}_{x}{\mathrm{B}}_{1-x}\mathrm{N}}-{E}_{\mathrm{g},\mathrm{ BN}}\right)/\left({E}_{\mathrm{g}, \mathrm{AN}}-{E}_{\mathrm{g},\mathrm{ BN}}\right)$$ ξ E g = E g , A x B 1 - x N - E g , BN / E g , AN - E g , BN of the corresponding ternary alloys is used rather than one directly invoking the alloy composition.