Determination of <sup>210sup>Po content of vietnamese tobacco samples

Smoking is one of the leading causes of preventable death. In recent years, numerous countries have initiated the prohibition of smoking in restaurants, workplaces and public spaces. The Vietnamese government intends to follow the precautions against public smoking as well. Over and above the number of some hazardous chemical components found in tobacco, <sup>210sup>Po isotope content could enhance the probability of the development of lung cancer. In this study 14 Vietnamese tobacco products (commercial cigarettes and pipe tobacco) <sup>210sup>Po activity concentration were determined using PIPS semiconductor alpha spectrometry. The results showed that the 210Po activity concentration of the investigated samples varied between 7.40 ± 1.09 - 128.64 ± 11.22 mBq g<sup>-1sup>. The average <sup>210sup>Po content of commercial cigarettes was 15.5 mBq g<sup>-1sup>, whilst the average of pipe tobacco was 20.4 mBq g<sup>-1sup>. To estimate the risk of inhalation of <sup>210sup>Po isotopes originating as a result of smoking, dose estimations were carried out. © Versita Sp. z o.o.

Photoionization of Co<sup style="margin: 0px; padding: 0px; border: 0px; outline-style: none; font-weight: inherit; font-style: inherit; font-size: 0.85em; font-family: inherit; line-height: 0; text-align: inherit;">+sup> and electron-impact excitation of Co<sup style="margin: 0px; padding: 0px; border: 0px; outline-style: none; font-weight: inherit; font-style: inherit; font-size: 0.85em; font-family: inherit; line-height: 0; text-align: inherit;">2 +sup> using the Dirac R-matrix method

Modelling of massive stars and supernovae (SNe) plays a crucial role in understanding galaxies. From this modelling we can derive fundamental constraints on stellar evolution, mass-loss processes, mixing, and the products of nucleosynthesis. Proper account must be taken of all important processes that populate and depopulate the levels (collisional excitation, de-excitation, ionization, recombination, photoionization, bound–bound processes). For the analysis of Type Ia SNe and core collapse SNe (Types Ib, Ic and II) Fe group elements are particularly important. Unfortunately little data is currently available and most noticeably absent are the photoionization cross-sections for the Fe-peaks which have high abundances in SNe. Important interactions for both photoionization and electron-impact excitation are calculated using the relativistic Dirac atomic R-matrix codes (DARC) for low-ionization stages of Cobalt. All results are calculated up to photon energies of 45 eV and electron energies up to 20 eV. The wavefunction representation of Co III has been generated using GRASP0 by including the dominant 3d<sup style="margin: 0px; padding: 0px; border: 0px; outline-style: none; font-size: 0.85em; font-family: "Lucida Grande", "Lucida Sans Unicode", Tahoma, Verdana, Arial, Helvetica, sans-serif; line-height: 0; background-color: rgb(255, 255, 255);">7sup>, 3d<sup style="margin: 0px; padding: 0px; border: 0px; outline-style: none; font-size: 0.85em; font-family: "Lucida Grande", "Lucida Sans Unicode", Tahoma, Verdana, Arial, Helvetica, sans-serif; line-height: 0; background-color: rgb(255, 255, 255);">6sup>[4s, 4p], 3p<sup style="margin: 0px; padding: 0px; border: 0px; outline-style: none; font-size: 0.85em; font-family: "Lucida Grande", "Lucida Sans Unicode", Tahoma, Verdana, Arial, Helvetica, sans-serif; line-height: 0; background-color: rgb(255, 255, 255);">4sup>3d<sup style="margin: 0px; padding: 0px; border: 0px; outline-style: none; font-size: 0.85em; font-family: "Lucida Grande", "Lucida Sans Unicode", Tahoma, Verdana, Arial, Helvetica, sans-serif; line-height: 0; background-color: rgb(255, 255, 255);">9sup> and 3p<sup style="margin: 0px; padding: 0px; border: 0px; outline-style: none; font-size: 0.85em; font-family: "Lucida Grande", "Lucida Sans Unicode", Tahoma, Verdana, Arial, Helvetica, sans-serif; line-height: 0; background-color: rgb(255, 255, 255);">6sup>3d<sup style="margin: 0px; padding: 0px; border: 0px; outline-style: none; font-size: 0.85em; font-family: "Lucida Grande", "Lucida Sans Unicode", Tahoma, Verdana, Arial, Helvetica, sans-serif; line-height: 0; background-color: rgb(255, 255, 255);">9sup> configurations, resulting in 292 fine structure levels. Electron-impact collision strengths and Maxwellian averaged effective collision strengths across a wide range of astrophysically relevant temperatures are computed for Co III. In addition, statistically weighted level-resolved ground and metastable photoionization cross-sections are presented for Co II and compared directly with existing work.

Energy transfer rates and population inversion investigation of sup(1)Gsub(4) and sup(1)Dsub(2) excited states of Tmsup(3+) in Yb:Tm:Nd:KYsub(3)Fsub(10) crystals

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Population inversion between the sup(3)Hsub(4) and the sup(3)Fsub(4) excited states of Tmsup(3+) investigated by means of numerical solutions of the rate equations system in Tmsup(3+)-doped and Tmsup(3+), Hosup(3+)-codoped fluoride glasses

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Energy transfer rates and population inversion of sup(4)Isub(11/2) excited state of Ersup(3+) investigated by means of numerical solutions of the rate equations system in Er:LiYFsub(4) crystal

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)