An inexpensive photoreactor using LED light sources and a fibre-optic CCD spectrophotometer as a detector was built by designing a special cell holder for standard 1.000 cm cuvettes. The use of this device was demonstrated by studying the aqueous photochemical reaction of 2,5-dichloro-1,4-benzoquinone. The developed method combines the highly quantitative data collection of CCD spectrophotomete...

In previous communications the authors have described the cellular and subcellular responses to ultraviolet irradiation directed to whole Chang liver cells and to portions of Chang liver cells (3-6). Two sources of ultraviolet have been utilized in these studies. One source was a mercury arc lamp the output of which was passed through a grating monochromator, and the second source was the ultra...

The determination of hydroxymethylfurfural (HMF) in bee honey is performed by the spectrophotometric methods Winkler's and White's. Winkler method reads absorbances visible region spectrum, White measures ultraviolet (UV) regions spectrum. This study aims to compare methodologies HMF honey. For study, it was used a UV-visible spectrophotometer, 10 mm optical path quartz cuvettes, ten samples di...

Abstract Chemical processes were used to synthesize ZnO low-dimensional structure including thin film nanorod and nanoparticle. was prepared by sol-gel spin coating method while hydrothermal process nanoparticle synthesized via co-precipitation route. The structural, morphological, optical photoresponse properties investigated XRD, FESEM, UV-Visible spectrophotometer, I-V I-t measurement. Compa...

Endophytic actinomycetes are considered as one of the relatively unexplored potential sources in search of antibiotic producer against antibiotic resistant pathogens. A potent strain isolated from Catharanthus roseus that displays antibacterial potential against antibiotic resistant human pathogen Staphylococcus aureus was characterized and designated as Micrococcus yunnanensis strain rsk5. Rsk...

We propose an algorithm to retrieve the global features of the spectral dependence of the ultraviolet (UV) irradiance from integrated, broadband UV measurements performed with a set of photodiodes with different UV filters. This fit, when applied to ground-based measurements and compared with the incident Solar spectral irradiance on the top of the atmosphere, may be used to extract the spectra...

The influences of chondroitin sulfate C (C6S) on size, aggregation, sedimentation, and Zeta potential of sub-micron calcium oxalate monohydrate (COM) and calcium oxalate dihydrate (COD) crystallites with mean sizes of about 330 nm were investigated using an X-ray diffractometer, nanoparticle size Zeta potential analyzer, ultraviolet spectrophotometer, and scanning electron microscope, after whi...

Gold sodium thiomalate, a drug used widely in the therapy of rheumatoid arthritis, was found to be an activator of latent human polymorphonuclear leukocyte collagenase. The activation was demonstrated by two distinct and independent collagenase assays: by recording with a spectrophotometer at 227 nm the enzyme-induced increase in ultraviolet difference absorbance of native type I collagen conne...

Orthodox black tea quality depends upon the amount of certain organic compounds present and out of these, theaflavins (TF) and thearubigins (TR) are the most important ones While TF is responsible for attractive golden colour, increased brightness and astringency in tea liquor, TR is reddish brown, reduces the brightness of tea liquor and contribute mostly for the ashy taste of the liquor with ...