DIAGNOSTIC SPECTROSCOPIQUE EN TEMPERATURE ELECTRONIQUE DES PLASMAS PHOTOIONISES

In this work, we are interested in the diagnostics in electronic temperature of a plasma purely photoionized, based on the intensity ration of lines emitted by ions helium-like, witch have an atomic number Z relatively small. We considered the three lines corresponding to the transitions starting from the excited levels 1s2l towards the fundamental level 1s2 1S0, like appropriate lines. More precisely, the line of resonance w due to the transition 1s2p 1P1 1s2 1 S0, the line of intercombinaison (x,y) 1s2p 3 P2,1 1s2 1 S0 as well as prohibited line z due to the transition 1s2 3 S1 1s2 1 S0. These lines appear clearly in the spectra of astrophysical plasmas. As helium-like ion, we chose two, the oxygen O6+ (Z=8) and neon Ne8+ (Z=10). We carried out calculations of the ration of lines intensity G=(zxy)/w of O6+ and Ne8+ according to the electronic temperature in the range going from 105 to 107 K. We will see that, like it was shown by Gabriel and Jordan in 1969, this intensity ration can be very sensitive to the temperature electronic and practically independent of the electronic density. Consequently, the ration G can be used to determine in a reliable way the electronic temperature of plasma observed

SPECTROSCOPIC DIAGNOSIS IN ELECTRONIC TEMPERATURE OF PHOTOIONISE PLASMAS

In this work, we are interested in the diagnostics in electronic temperature of a plasma purely photoionized, based on the intensity ration of lines emitted by ions helium-like, which have an atomic number Z relatively small. We considered the three lines corresponding to the transitions starting from the excited levels 1s2l towards the fundamental level 1s2 1S0, like appropriate lines. More precisely, the line of resonance w due to the transition 1s2p 1P1 --- 1s2 1 S0, the line of intercombinaison (x,y) 1s2p 3 P2,1 --- 1s2 1 S0  as well as prohibited line z due to the transition 1s2 3 S1 --- 1s2 1 S0. These lines appear clearly in the spectra of astrophysical plasmas. As helium-like ion, we chose two, the oxygen O6+ (Z=8) and neon Ne8+ (Z=10). We carried out calculations of the ration of lines intensity G=(z+x+y)/w of O6+ and Ne8+  according to the electronic temperature in the range going from 105 to 107 K. We will see that, like it was shown by Gabriel and Jordan in 1969 [1], this intensity ration can be very sensitive to the temperature electronic and practically independent of the electronic density. Consequently, the ration G can be used to determine in a reliable way the electronic temperature of plasma observed [2].</p

Hyperfine-induced depolarization effect in the X-ray line emission

The degree of linear polarization of the line x corresponding to the transition \mathrm {1s2p\,^3P_2\!\rightarrow \!1s^2\,^1S_0} is considered for Helium-like ions with non-zero nuclear spin. We are interested in this paper to seven ions: P$$^{13+}$$, V$$^{21+}$$, Mn$$^{23+}$$, As$$^{31+}$$, Rb$$^{35+}$$, Y$$^{35+}$$ and Nb$$^{39+}$$ which are excited by electrons beam. In such ions, two kind of transitions occurs in the line x: the hyperfine-induced electric dipole E1 transition and the magnetic quadrupole M2 transition. From our results, we find that when we take into account this two kind of transitions without interference between the two channels E1 and M2, this leads to a drastic depolarization. However, the consideration of the interference effect leads to an increase in the polarization degree, slight for the whole line x and substantial for its individual hyperfine components

TEMPERATUREEFFECT OFELECTRICALPROPERTIES OF CIGS SOLAR CELL

<p>In this paper we are interested in studying the copper–indium–gallium–selenium (CIGS) solar cells sandwiched between cadmium sulfide (CdS) and ZnO as buffer layers, and Molybdenum (Mo). Thus, we report our simulation results using the capacitance simulator (SCAPS) in terms of layer thickness, absorber layer band gap and operating temperature to find out the optimum choice. An efficiency of 20.61% (with V_oc of 635.2mV, J_sc of 44.08 mA/cm² and fill factor of 0.73) has been achieved with CdS used as buffer layer as the reference case. It is also found that the high efficiency CIGS cells with the low temperature were a very high efficiency conversion.</p

STUDY OFPERFORMANCES OF ORGANIC SOLAR CELLSBYANALYSIS OF MAIN COMPONENTS

<p>The analysis of the data is currently, in the statisticians, the object of a true phenomenon of mode, characterized at the same time by the passion and the rejection.To determine the characteristics of a whole of data are obviously not an end in itself, but this lapse of memory is unfortunate because the type of data available always influences the direction of research.The factorial analysis in normalized principal components (PCA), is particularly adapted to the reduction of tables of measurements, where one generally works on a matrix of correlation between characters.In this article we will report our results of analysis of performances of organic solar cellsby using what one call the datamining materials.All information was presented in the tables envisaged by an ACP method of the studied semiconductors.Factorial analyzes substitutes for primitive measurements of new variables or factors (which are linear combinations of the primitive variables) with the help of which it is thus possible to optimize the visualization of the data in a restricted number of figures. Large at the modo we present, the results related to the development of new approaches of Datamining, Analysis in principal components (ACP), of the data-processing techniques which were applied to organic semiconductors and combined with metals to predict new materials or best performing coatings.</p

NUMERICAL SIMULATION AND OPTIMIZATION OF PERFORMANCES OF A SOLAR CELL BASED ON CdTe

<p>This article has as an aim the study and the simulation of the photovoltaic cells containing CdTe materials, contributing to the development of renewable energies, and able to feed from the houses, the shelters as well as photovoltaic stations… etc. CdTe is a semiconductor having a structure of bands with an indirect gap of a value of 1,5 eV at ambient temperature what means that photon wavelength of approximately 1200 nm will be able to generate an electron-hole pair. One speaks about photogeneration. We will lay the stress, initially, on the essential design features of a photovoltaic module (the open-circuit tension, the short-circuit current, the fill factor, and the output of the cell)<strong>, </strong>our results was simulated with the SCAPS computer code in one dimension which uses electrical characteristics DC and AC of the thin layers heterojunctions. The results obtained after optimization are: V_CO = 0.632V, Jsc = 39.1 mA/cm2, FF=82.98 % and the output energy of conversion is 18.26%.Optimization is made according to the temperature and the wavelength.</p