the complexive abilities of 5,11,17-tddert-butyl-23 amino-25.26,27,28-tet3propoxy-calix[4]arere and5,1127-tri-amino-23 acelyktert-butylamide-25,26,27,28-tetrabutoxy-calixplarene towards alkali metalions lit nat, kt ric and cs+ in methanol-chloroform mixture have been evaluated at 25 °c, using uvvis spectrophotometric techniques. the results showed that the hgands are capable to complex with all...

Recent advances in portable spectrophotometers have allowed researchers to collect quantitative, objective data on colour. There are few comparisons of the different methods used to summarize and analyse spectrophotometer data, however. Using colour data on over 900 species of birds, we compared three methods of calculating sexual dichromatism using spectrophotometer data. We also compared sexu...

This research aims to study about developing and demonstrating the low-cost and portable light absorbance measurement device for using and learning in analytical experiments. In chemistry experiments, the concentration of solutions is important for mixing the sample or making medicines. In present, a UV-spectrophotometer is commonly used to check the absorbance of solution for investigating con...

The aim of this study is ultraviolet and infrared spectral characterization of eight new xanthine derivatives. Spectral analysis was performed using an Agilent 8453 Series spectrophotometer and a Tensor 27 Optics FT-IR spectrophotometer. The UV and IR spectra for xanthine derivatives were obtained and in addition, the wavelength maxima of absorption bands and characteristics have been established.

BACKGROUND AND OBJECTIVES This in vitro study compared the shade matching abilities of an intraoral spectrophotometer and the conventional visual method using two shade guides. The results of previous investigations between color perceived by human observers and color assessed by instruments have been inconclusive. The objectives were to determine accuracies and interrater agreement of both met...

Corresponding Author: Dr. Gabriele Corciolani, Via Derna 4, 58100 Grosseto (Italy) E-mail: gabriele.corciolani@gmail.com; Tel/Fax: +39056425384 Abstract Objectives: The aim of this study was to evaluate the repeatability of readings with a clinical spectrophotometer in comparison with a laboratory one. Materials and Methods: A stand alone clinical spectrophotometer (Easyshade, Vita) and a labor...