The three-photon absorption (3PA) in nanostructure wide-band gap ZnO semiconductor material is observed under high intensity femtosecond Titanium-Sapphire laser of 800 nm wavelength excitation. The ZnO film was prepared by chemical spray pyrolysis technique with substrate temperature of 400 o C. The optical properties concerning the absorption, transmission, reflection, Raman and the photolumin...

Scattering-type scanning near-field optical microscopy (s-SNOM) and Fourier transform infrared nanospectroscopy (nano-FTIR) are emerging tools for nanoscale chemical material identification. Here, we push s-SNOM and nano-FTIR one important step further by enabling them to quantitatively measure local dielectric constants and infrared absorption. Our technique is based on an analytical model, wh...

Toxic odour causes pollution to environment. Removal of odour from wet processing sections of leather tanneries is important to preserve safety and occupational health. Such odour causing gases are identified in nature and are identified mostly as ammonia, Hydrogen sulfide and Volatile organic compounds. These gases, evolving from tanning drums, were experimentally quantified and analysed. Tech...

The concentration of atmospheric oxygen is measured over a 540-m path using supercontinuum absorption spectroscopy. The absorption data compared favorably with MODTRANTM 5 simulations of the spectra after adjusting for the differences of index of refraction of air and matching the instrument spectral resolution, as described by the effective slit width. Good agreement with the expected atmosphe...

Correlating spatial chemical information with the morphology of closely packed nanostructures remains a challenge for the scientific community. For example, supramolecular self-assembly, which provides a powerful and low-cost way to create nanoscale patterns and engineered nanostructures, is not easily interrogated in real space via existing nondestructive techniques based on optics or electron...

The nonlinear optical properties of carbon nanotubes (CNTs) have been studied by using the Z-scan technique. Experiments are performed by CW second harmonic of Nd-YAG laser at 532 nm wavelength with a power of 40 mW. The samples are synthesized by the chemical vapor deposition (CVD) method in the presence of Nickel and Nickel-Cobalt catalysts. In this work, for the first time, effect of the typ...

in the process of vermicomposting, the earthworms eisenia fetida have been exposed to various metals with different concentrations to study the effects on worms’ bioaccumulation. the study was carried within 14 days of exposure. five different chemical compounds in various concentrations were added as mixture solutions to the experimental containers. metals concentrations were measured in earth...

A multiwavelength spectrophotometric approach has been developed to determine acid dissociation constants (pKa values) of sparingly soluble drug compounds. UV absorption spectra of the drug solution are acquired using a versatile device based on a fiber optics dip probe, a light source and a photodiode array (PDA) detector while the PH and the ionic strength of the chemical system is manipulate...

The chemical nature of the sulfur in bacterial sulfur globules has been the subject of controversy for a number of years. Sulfur K-edge X-ray absorption spectroscopy (XAS) is a powerful technique for probing the chemical forms of sulfur in situ, but two groups have used it with very different conclusions. The root of the controversy lies with the different detection strategies used by the two g...

In comparison with multispectral image data, hyperspectral (HS) imagery with higher spectral resolution provides sufficient spectral resolution to describe diagnostic absorption signatures. Specific chemical bonds in materials, whether solid, liquid or gas, determine the surface reflectance and emittance, as variations in material composition often cause shifts in the position and shape of abso...