Optical pumping of an optically thick atomic vapor typically requires a quenching buffer gas, such as N2, to prevent radiation trapping of unpolarized photons which would depolarize the atoms. We show that optical pumping of a trace contamination of Rb present in K metal results in a 4.5 times higher polarization of K than direct optical pumping of K in the absence of N2. Such spin-exchange pol...

objective(s):cefixime (cfx), is a semi-synthetic third-generation oral cephalosporin antibiotic that is prescribed for the treatment of susceptible infections. there are some procedures for the determination of cfx in pharmaceutical formulations and biological samples. herein a spectrofluorimetric method was proposed for cfx determination based on the fluorescence quenching of terbium-danofloxa...

Stimulated gluon emission and thermal absorption, in addition to induced radiation, are considered for an energetic parton propagating inside a quark-gluon plasma. In the presence of thermal gluons, stimulated emission reduces, while absorption increases, the parton's energy. The net effect is a reduction of the parton energy loss. Though decreasing asymptotically as T/E with the parton energy,...

The gluon radiation induced by multiple scattering of a hard parton in expanding quark-gluon plasma is investigated. The radiative energy loss of hard parton jet is shown to decrease considerably when angular size of extracted jet goes up, but the fraction of loss survives even for the reasonable wide cone of angles due to the coherent effects taking into account the rescattering of the radiate...

A strong suppression of non-photonic electrons in Au+Au collisions is observed at Rhic. This is in disagreement with the expected dominance of the energy loss via gluon radiation, which predicts a much weaker suppression of heavy flavours due to the dead cone effect. However, collisional energy loss is also important, as demonstrated recently by the Soft Colour Interaction Jet Quenching model. ...

The glass system 42.5P2O5–42.5B2O3–( $$15-x$$ ) Li2O– $$x$$ MoO3 = $$(0, 2.5,5.10 \;{\text{and}}\;15$$ ), was fabricated using a melt-quenching technique. Optical features are examined depending on measuring the absorption and transmission of prepared glasses. energy gap ( $$E_{{{\text{opt}}}}$$ increases from 2.23 to 2.49 e.V. Urbach $$E_{u}$$ decreases 0.513 0.5 Basicity, polarizability, elec...

The binding of gatifloxacin to bovine serum albumin (BSA) in aqueous solution was studied using fluorescence spectroscopy and absorbance spectra, Further, the interactions influenced by Fe3+ and Cu2+ were also explored in this work. Based on Scatchard's site-binding model and florescence quenching, practical formulas for small molecule ligands to bio-macromolecules have been proposed. The bindi...

The study of penetrating probes constitutes a key aspect of the relativistic heavy ion program. In the hadronic sector, jet quenching, for example, has been a striking revelation, and has contributed to expose the qualitatively different physics that appeared in the transition from the SPS to RHIC. In this context, electromagnetic radiation also defines a privileged class of observables owing m...