The wavelength accuracy of the Brewer spectrophotometer in the 280-360-nm spectral range is improved by a new grating-drive mechanism and a new dispersion function derived from the Brewer geometry. With the new mechanism, the reproducibility of wavelength settings for spectral emission lines is better than 0.3 pm (0.0003 nm) and, with a thermally compensated version, the effect of temperature i...

the subject of geometry and proportions has been regarded as an issue which has a close relationship with architecture. since the entire universe, living beings and the human geometry can be seen clearly, that’s why our unconscious essence has accustomed to these proportions whereby reflection of this mentality can be seen in the architect’s hands and thought in the architecture. it can witness...

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 green synthesis method, which is one of the methods obtaining nanoparticles; It a preferred method because it simpler, environmentally friendly, economical and turns into product in short time. In this study, was aimed to investigate CuNp possibilities antimicrobial activity Np by using extract Peumus boldus, an endemic plant. synthesized CuNps were characterized scanning electron microscop...

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...