Tin oxide (SnO2)nanoparticles were synthesized by co-precipitation method and the synthesized nanoparticles were annealed at different temperatures for characterization. The powders were investigated with X-ray diffraction, scanning electron microscopy and optical spectroscopy. The structural characterization was carried out by X-ray diffraction which confirms the crystalline nature ...

 A polymethylmethacrylate (PMMA) microstructured polymer optical fiber (mPOF) is fabricated and characterized. Using the cut-back technique the fiber loss is measured which is higher than the step-index silica fibers. Through a novel experimental scheme, the backward Stokes spectrum of the fabricated mPOF is recorded over a range exceeding 3000 cm‑1 during the cut-back method and compared ...

   In this work, the effect of annealing temperature on the microstructure, morphology, and optical properties of Cu-doped nanostructured MnO2 thin films were studied. The thin films were prepared by sol-gel spin-coating technique on glass substrates and annealed in the air ambient at 300, 350, 400 and 450 °C temperatures. The structural, morphological and optical properties of t...

Dispersion, as the characteristic variation of refractive index with wavelength, is more pronounced, where the wavelength is approaching to the absorption band. In ultra-optical glasses, the nonlinear refractive index, concerning to the light intensity dependent phenomenon, becomes considerable. Here, two ultra-optical property glass systems; TiO2-Bi2O3-PbO (TBP...

We present infrared imaging of a sample of 11 hot spots in the lobes of powerful radio galaxies. We have detected infrared counterparts to the hot spots in 3C 20West, 3C 33 South, 3C 111East and 3C 303West all of which have known optical counterparts as well. In addition, we detected the radio jet of 3C 303 in the near infrared. Four other hot spots, those in 3C 20East, 3C 65 (both sides), and ...

The optical spectrum of reduced myeloperoxidase (EC 1.11.1.7) displays an unusual red shift of the Soret band which is at 472 nm and the alpha-band which is at 636 nm. The spectral properties of myeloperoxidase can be modified by means of acid treatment. Upon short exposure to acid (pH 1.7) the red-shifted optical absorption spectrum of the reduced enzyme (lambda max at 472 nm) was blue-shifted...

The transmittance values measured in IR reflection-absorption (RA) spectra were used to determine the optical constants of dielectric films laid on solid substrates. When the recorded spectra show interference fringes, one can determine the film thickness. The PbSe film thickness was obtained by interpreting the interference fringes from the reflexion-absorption IR spectra recorded at two diffe...

in this paper metal-assisted chemical etching has been applied to pattern porous silicon regions and silicon nanohole arrays in submicron period simply by using positive photoresist as a mask layer. in order to define silicon nanostructures, metal-assisted chemical etching (mace) was carried out with silver catalyst. provided solution (or materiel) in combination with laser interference lithogr...

We propose occupying the guard bands in closely spaced WDM systems with redundant signal spectral components to increase tolerance to frequency misalignment and channel shaping from multiplexing elements. By cyclically repeating the spectrum of a modulated signal, we show improved tolerance to impairments due to add/drop multiplexing with a commercial wavelength selective switch in systems usin...