Scopul nostru este sprijinirea şi promovarea cercetării ştiinţifice şi facilitarea comunicării între cercetătorii români din întreaga lume.
The present work describes a modified colloidal synthesis route for the preparation of CdSe nanocrystals, which were further embedded in a polystyrene matrix. Used as a reaction medium, glycerin makes it possible to obtain nanocrystals at lower temperatures in all process stages and an easier separation from the reaction mass. The influence of two different cadmium compounds used as primary cadmium sources over the quality of synthesized CdSe nanocrystals
Read moreThe preparation of two highly luminescent europium(III) and terbium(III) complexes with succinimide (SI) and N-hydroxysuccinimide (NHSI) were reported, which were further investigated through elemental chemical analysis, thermal analysis, FT-IR, powder X-ray diffraction, SEM and fluorescence spectroscopy. Data collected through these analysis revealed the formation of the Eu(III) and Tb(III) complexes with the above mentioned ligands at a metal to
Read moreThe present work studies the removal of indigo carmine from aqueous solutions by an electrocoagulation (EC)/granular activated carbon (GAC) adsorption coupling process. The kinetics of this coupling process was studied using several GACs and different amounts of adsorbent material in order to identify the most appropriate adsorbent and dosage, respectively, for enhancing wastewater treatment. The influence of current density on the removal efficiency
Read moreThe experimental design methodology was applied for response surface modelling (RSM) of a packed-bed based pilot-scaled set-up for water vapour adsorption on impregnated alumina grains. Experimental breakthrough cuwes were determined. The variables considered were the ratio between the volume of adsorbent bed and air now rate (residence time), a geometrical parameter, the ratio between adsorption column diameter and the bed height, and air relative
Read moreThis study presents the neural network modeling of monochlorotriazinyl- B-cyclodextrin (MCT-B-CD) grafting on paper supports. Neural networks are very efficient in predicting the evolution of a process, providing a good approximation ot the studied grafting process, further used for the interpolation and extrapolation of the results beyond the experimental range. The grafting was realized by a pad-dry-cure treatment and the mathematical model has
Read moreThis paper presents an experimental study on the removal of Indigo Carmine dye from aqueous solutions using a batch stirred electrocoagulation reactor. The experimental tests were carried out in a discontinuous system provided with steel electrodes. The main purpose was to investigate the effects of the operating parameters, such as pH, initial concentration, electrolysis duration, current density, and electrolyte support concentration, on the treatment
Read moreReliable seismic waves characterization is essential for better understanding wave propagation phenomena, providing new physical insight into soil properties. Many works in this area have been based on detecting special patterns or clusters in seismic data, event detection using parametric models and time-frequency analysis. In this paper we present a new approach making use of the short-term time-frequency Renyi entropy and maximum a posteriori
Read moreUsually, dam monitoring systems are based on both boundary conditions (temperature, rainfall, water level, etc.) and structural responses. Statistical analysis tools are widely used to determine eventual unwanted behaviors. The main drawback of this approach is that the structural response quantities are related to the external loads using analytical functions, whose parameters do not have physical meaning. In this paper a new approach, based on
Read moreThe paper presents a new approach for machine vibration analysis and health monitoring based on blind source separation (BSS). So, the problem is transferred from the original space of the measurements to the space of independent sources, where the reduced number of components is going to simplify the monitoring problem while the vibration analysis methods are going to be applied for scalar signals. The assessment of the approach on a real machine
Read more