Prediction using pure standards is expected to be biased whenever the slope of the calibration is affected by the presence of sample matrix. Moreover, in the presence of unknown spectral interferents, first-order algorithms like partial least squares cannot be used. In this study, a method for determination of carvedilol (CAR) in tablet and urine samples is proposed by excitation-emission fluor...

There is no satisfactory mechanism to detect premalignant lesions in the upper aero-digestive tract. Fluorescence spectroscopy has potential to bridge the gap between clinical examination and invasive biopsy; however, optimal excitation wavelengths have not yet been determined. The goals of this study were to determine optimal excitation-emission wavelength combinations to discriminate normal a...

Second order advantage of excitation-emission fluorescence matrix was applied for the simultaneous determination of ibuprofen and caffeine. The proposed method is based on the measurement of the native fluorescence and recording emission spectra of ibuprofen and caffeine in different excitation wavelengths. The mixture of these compounds was resolved by multivariate curve resolution coupled wit...

We report on studies of plasmon excitation in Mg under the impact of slow Heþ ions in the incident energy range 0.1–0.5 keV. Consistent with studies on Al surfaces, a transition from surface to bulk plasmon excitation occurs as the energy of the ion is increased. Previous methods in the literature to obtain information about yields of electron emission from plasmon decay are discussed. A new da...

Fluorescence spectroscopy has been demonstrated to be a powerful tool for characterizing phytoplankton communities in marine environments. Using different fluorescence spectra techniques, it is now possible to discriminate the major phytoplankton groups. However, most of the current techniques are based on fluorescence excitation measurements, which require stimulation at different wavelengths ...

We present a photoluminescence and photoluminescence excitation study of CdTe quantum dots, prepared via a novel organometallic approach. The global photoluminescence (excited at the energy above the absorption edge) showed a red shift of 75 meV with respect to the first absorption peak. This band edge emission was found to be strongly dependent on the excitation photon. Resonant emission spect...

lithium disilicate nano-powders were synthesized via a mild condition hydrothermal reaction at 180 ºc for 48 and 72 h with a non stoichiometric1:2 li:si molar ratio in naoh aqueous solution using li2co3 and sio2.h2o as raw materials. the synthesized materials were characterized by powder x-ray diffraction (pxrd) technique and fourier transform infrared (ftir) spectroscopy. the xrd data showed t...

This study describes a simple and rapid approach of monitoring ibuprofen (IBP). Unfolded principal component analysis-artificial neural network (UPCA-ANN) and excitation-emission spectra resulted from spectrofluorimetry method were combined to develop new model in the determination of IBF in human serum samples. Fluorescence landscapes with excitation wavelengths from 235 to 265 nm and emission...

This study describes a simple and rapid approach of monitoring ibuprofen (IBP). Unfolded principal component analysis-artificial neural network (UPCA-ANN) and excitation-emission spectra resulted from spectrofluorimetry method were combined to develop new model in the determination of IBF in human serum samples. Fluorescence landscapes with excitation wavelengths from 235 to 265 nm and emission...