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M S Jovanović

Publications and source records attributed to M S Jovanović.

6 recordsLinked to original sources
PubMed2004

Determination of the ionization constants of 4-iodo-2,6-dimethylphenylcarbamoylmethyl iminodiacetic acid.

In order to develop a radiopharmaceutical for hepatobiliary scintigraphy with better hepatobiliary properties new ligand for complexation of 99mTc, 4-iodo-2,6-dimethylphenylcarbamoylmethyl iminodiacetic acid (METHYLIODIDA), was synthesized. Acid-base equilibria of METHYLIODIDA were studied potentiometrically, because these data are important for determination of complex formation conditions. It was established that METHYLIODIDA undergoes a complex acid-base equilibrium due to its zwitterionic nature and four proton-binding sites. The stoichiometric ionization constants were determined at 25 degrees C and constant ionic strength 0.1M (NaClO(4)): pK1=1.7+/-0.1; pK2=2.44+/-0.07; pK3=6.29+/-0.02 and pK4=10.91+/-0.06, respectively.

Chemistry, Pharmaceutical↗
PubMed2002

Nonlinear features of two-plasmon decay in a long-scale-length plasma.

A transparent model of two-plasmon decay in a spatially homogeneous or long-scale-length plasma, reproducing the main experimentally observed nonlinear features, is presented. Secondary coupling between the plasma waves and the ion-acoustic waves, including their frequency mismatch, proves to be the principal saturation mechanism of the instability. The wave amplitude time evolution and spectra as well as the hot-electron generation properties are compared to the experimental data.

Journal Article↗
PubMed2002

Stochastic heating and acceleration of electrons in colliding laser fields in plasma.

We propose a mechanism that leads to efficient acceleration of electrons in plasma by two counterpropagating laser pulses. It is triggered by stochastic motion of electrons when the laser fields exceed some threshold amplitudes, as found in single-electron dynamics. It is further confirmed in particle-in-cell simulations. In vacuum or tenuous plasma, electron acceleration in the case with two colliding laser pulses can be much more efficient than with one laser pulse only. In plasma at moderate densities, such as a few percent of the critical density, the amplitude of the Raman-backscattered wave is high enough to serve as the second counterpropagating pulse to trigger the electron stochastic motion. As a result, even with one intense laser pulse only, electrons can be heated up to a temperature much higher than the corresponding laser ponderomotive potential.

Journal Article↗
PubMed1999

Self-organization in a dissipative three-wave interaction.

A nonlinear three-wave interaction in an open dissipative plasma model of a stimulated Raman backscattering is studied. An anomalous kinetic dissipation due to electron trapping and plasma wave breaking is accounted for in a hybrid kinetic-fluid scheme. We simulate a finite plasma with open boundaries and vary a transport parameter to examine a route to spatio-temporal complexity. An interplay between self-organization at micro (kinetic) and macro (fluid) scales is found through quasi-periodic and intermittent evolution of dynamical variables, dissipative structures and related entropy rates. A consistency with a general scenario of self-organization is claimed.

Journal Article↗