Search results for "ACOUSTIC"

Optimization of CASA-Mot Analysis of Donkey Sperm : optimum Frame Rate and Values of Kinematic Variables for Different Counting Chamber and Fields

2020

In order to optimize the donkey sperm motility analysis by the CASA (Computer Assisted Sperm Analysis)-Mot system, twelve ejaculates were collected from six jackasses. Capillary loaded chamber (CLC), ISAS&reg

1992

The ultrasounds-ionic liquids synergy on the copper catalyzed azide-alkyne cycloaddition between phenyl acetylene and 4-azidoquinoline

2015

Abstract The effect of ultrasound irradiation on the copper catalyzed azide–alkyne cycloaddition between phenylacetylene and 4-azidoquinoline has been studied in solution of different ionic liquids. In particular, we used ionic liquids featuring both aliphatic and aromatic mono- and dications, as well as anions differing in size, symmetry and coordination ability. We also examined the influence of the ionic liquids structural features on the reaction outcomes, finding that under magnetic stirring reactivity is favorably affected by the solvent structural organization, while under sonochemical conditions an opposite trend was observed. In all cases examined, sonochemical activation leads to …

Phase transitions in some n-alkanes and petroleum waxes — investigation by photoacoustic and exoelectron emission techniques

2000

Abstract The use of the photoacoustic (PA) effect and photostimulated exoelectron emission (EEE) technique in the investigation of first- and second-order phase transitions in pure n -alkanes such as n -C 22 , n -C 28 and n -C 32 and in three petroleum waxes having different carbon number distributions, have been examined. Changes in the amplitude and phase of the PA signal with temperature and the temperature dependence of the intensity of photostimulated EEE across the phase transitions have been measured. These measurements have shown that both the polymorphic phase transitions and melting of these hydrocarbons are accompanied by jumps or peaks of the PA amplitude and phase and EEE inten…

Front Cover: Magnetic Bistability in Macrocycle‐Based Fe II Spin‐Crossover Complexes: Counter Ion and Solvent Effects (Eur. J. Inorg. Chem. 34/2016)

2016

Effective conductivity in association with model structure and spatial inhomogeneity of polymer/carbon black composites

1996

The relationship between effective conductivity and cell structure of polyethylene/carbon composites as well as between effective conductivity and spatial distribution of carbon black are discussed. Following Yoshida's model both structures can, in a way, be said to be intermediate between the well known Maxwell-Garnett (MG) and Bruggeman (BR) limiting structures. Using TEM photographs on composites with various carbon blacks we have observed that the larger is Garncarek's inhomogeneity measure H of two-dimensional (2D) representative distribution of the carbon black, the smaller is the effective conductivity of the composite.

Iodine and mercury resonance lamps for kinetics experiments and their spectra in the far ultraviolet

2000

Electrodeless iodine and mercury iodide radio-frequency discharge lamps have been made to provide intense sources of resonance radiation of iodine and mercury in the 183-253 nm region. Production technology and emission spectra in the ultraviolet and vacuum ultraviolet regions are described. Both lamps (iodine and mercury iodide) are designed and used for monitoring the iodine 2P1/2 (206.163 nm) and 2P3/2 (183.038 nm) level population kinetics after flash photolysis of I2 or other precursor molecules in laboratory experiments. The technique is suitable for the investigation of the gas phase reaction kinetics following the photolysis of I2 in the presence of O3.

Amorphous polyphosphate nanoparticles: application of the morphogenetically active inorganic polymer for personalized tissue regeneration

2019

Diffusion of digital culture: analysis of the Internet forum of a MOOC

2017

When MOOCs are increasing all over the world as a mean for improving the diffusion of culture and science, it is interesting to observe how those MOOCS build communities of knowledge, and which is the impact of those communities on the acquisition of knowledge. In this article, we present the principles of design of the MOOC Digital & Culture Writing that aims to spread digital culture. Then, we analyse the messages posted on forums by the related community, and the cognitive process to which they refer. Posts analysis reveals reflexivity processes when participants are writing on forums. It appears that reflexivity cognitive processes are at the heart of both social interaction and digital…

Digital signal processing applied to noisy acoustic data.

2007

Frequently we deal with analog data from noisy acoustic measurements which need a preprocessing prior to the extraction of the information embedded. Data deterioration may be due to several reasons, for example: data recording on obsolete and technological poor support; bad signal conditioning (poor signal-to-noise ratio, non linearity and/or timevariance of the system under test). Sometimes information to be extracted from data is not conventional so it needs a dedicated processing. In this paper a novel audio data processing method from the autors experience in ancient open-air theatres research is shown.