The extraterrestrial Lyman-a emission was mapped by the OGO 5 satellite, when it was ABSTRACT outside the geocorona. Three maps, obtained at different periods of the year, are presented and analyzed. The results suggest that at least half of the emission takes place in the solar system, and give strong support to the theory that in its motion towards the apex, the sun crosses neutral atomic hyd...

tio2 nanorods can be used as dye-sensitized solar cells and as various sensors and photocatalysts. these nanorods are synthesized by a using thermal corrosion process in a naoh solution at 200 oc with tio2 powder as a source material. in the present work, the synthesis of tio2 nanorods in anatase, rutile and ti8o15 phases and the synthesis of tio2 nanorods by using the sol-gel method and alkali...

tio2 nanorods are synthesized by a thermal corrosion. in present work, synthesis of tio2 nanorods in anatase, rutile and ti8o15 phases, by using the sol-gel method and alkaline corrosion are reported. the morphologies and crystal structures of tio2 nanorods are characterized by use of field emission scanning electron microscopy, atomic force microscopy and x-ray diffractometer techniques. the o...

We calculate the spatial correlation of electrons and positrons emitted by internal pair conversion of Coulomb excited nuclei in heavy ion collisions. The alignment or polarization of the nucleus results in an anisotropic emission of the electron-positron pairs which is closely related to the anisotropic emission of γ-rays. However, the angular correlation in the case of internal pair conversio...

We present low-dispersion visible spectra of two regions of the 30 Doradus nebula. When corrected for atomic continuum emission and divided by the spectrum of the exciting and illuminating stars, one of the two spectra clearly shows Extended Red Emission (ERE) superimposed on the scattering component. This ERE band peaks around 7270Å and is 1140Å width. HAC grains are found to explain the obser...

In the framework of the PLAS’STER project, a prototype based on a RF plasma confined inside sterilization pouches for the treatment of medical devices has been developed. In this work, optical emission spectroscopy was used to study the plasma emission from VUV/UV to IR wavelengths range. The results showed the production of strong UV radiation, radicals and atomic species depending on the proc...

Porous silicon has been prepared using a vapor-etching based technique on a commercial silicon powder. Strong visible emission was observed in all samples. Obtained silicon powder with a thin porous layer at the surface was subjected to a photo-thermal annealing at different temperatures under oxygen atmosphere followed by a chemical treatment. Inductively coupled plasma atomic emission spectro...

We calculate the spatial correlation of electrons and positrons emitted by internal pair conversion of Coulomb excited nuclei in heavy ion collisions. The alignment or polarization of the nucleus results in an anisotropic emission of the electron-positron pairs which is closely related to the anisotropic emission of γ-rays. However, the angular correlation in the case of internal pair conversio...

The influence of spontaneous emission on the dynamical localization in atomic momentum transfer observed in recent experiments is investigated. Our numerical and analytical results indicate that contrary to previous expectation quantum diffusion due to decoherence by spontaneous emission is non-negligible in the experimental regime and may actually be visible in the measured data. Modifications...

We present low-dispersion visible spectra of two regions of the 30 Doradus nebula. When corrected for atomic continuum emission and divided by the spectrum of the exciting and illuminating stars, one of the two spectra clearly shows Extended Red Emission (ERE) superimposed on the scattering component. This ERE band peaks around 7270Å and is 1140Å width. HAC grains are found to explain the obser...