in this research, the coupling between non-gray radiation and separation convection flow in a duct is investigated numerically. distributions of absorption coefficients across the spectrum  are obtained from the hitran2008 database. the full-spectrum k-distribution method is used to deal with the non-gray part of the problem, while the gray radiation calculations are performed using the planck ...

the solar radiation received by earth surface is one of the most applicable parameter that is so important in hydrology, agriculture, meteorology and climatological modeling. because of very expensive instrument for measuring the radiation, researchers suggested many different experimental equations to estimate this parameter in different climate. seven models which are calibrated for semi-arid...

The optical absorption of nanoscale thickness semiconductor films on top of light-trapping structures based on optical interference effects combined with spectrum-splitting structures is theoretically investigated. Nearly perfect absorption over a broad spectrum range can be achieved in <100 nm thick films on top of a one-dimensional photonic crystal or metal films. This phenomenon can be attri...

Heterojunction system has been proved as one of the best architectures for photocatalyst owing to extending specific surface area, expanding spectral response range, and increasing photoinduced charges generation, separation, and transmission, which can provide better light absorption range and higher reaction site. In this paper, Indium Sulfide/Flexible Electrospun Carbon Nanofiber (In2S3/CNF)...

We present a new, high resolution HST/GHRS spectrum of quasar Q0302003, and use the He Lyman-α absorption, together with a high resolution Keck spectrum of the HI Lyman-α forest, to probe the distribution and ionization state of foreground gas just below the quasar redshift z ≈ 3.3. Within ≈ 4000 km/sec of the quasar redshift the spectrum shows a substantial flux (τ ≈ 1) with “He Lyman-α forest...

In this paper we examine the absorption and dispersion properties of a weak probe field via Electromagnetically Induced Transparency (EIT) in a four-level system. It is shown that under certain condition, using this model, the absorption cancellation is appeared and the medium becomes transparent to the weak probe field. It will be shown that the controlling of absorption and dispersion spectru...

We present a new, high resolution HST/GHRS spectrum of quasar Q0302003, and use the He Lyman-α absorption, together with a high resolution Keck spectrum of the HI Lyman-α forest, to probe the distribution and ionization state of the protogalactic foreground gas at z ≈ 3.3. Within ≈ 4000 km/sec of the quasar redshift the spectrum shows a substantial flux (τ ≈ 1) with “He Lyman-α forest” absorpti...