Showing papers by "Goran Pichler published in 1993"
TL;DR: In this paper, the authors performed DFWM spectroscopy on X−1Σ+−A1 Σ+ transitions in NaH produced in an indirect photochemical reaction between Na(3p and H2 and detected v″=1, 2 and 3 ground state vibrational levels of NaH molecules, whereas with resonance enhanced CARS, they observed v″ = 0 levels only.
Abstract: We performed DFWM spectroscopy on X−1Σ+−A1Σ+ transitions in NaH produced in an indirect photochemical reaction between Na(3p) and H2 and detected v″=1, 2 and 3 ground state vibrational levels of NaH molecules, whereas with resonance enhanced CARS, we observed v″=0 levels only. This different sensitivity can be explained by considering the Franck-Condon-factors and the relevant damping coefficients for the corresponding transitions in the NaH molecule. Time resolved DFWM spectroscopy showed that NaH(v″=1) molecules effectively live much longer than Na(3p) atoms which merely follow the laser excitation pulse.
14 citations
TL;DR: In this paper, a photochemical reaction of Na2(C 1 Πu) with Zn(4 1S 0) was reported, where the NaZn vapor mixture was prepared by introducing a controlled stream of sodium vapor into zinc vapor generated in a heatpipe oven.
Abstract: Electronically excited NaZn excimers have been produced in a photochemical reaction of Na2(C 1Πu) with Zn(4 1S0). The Na–Zn vapor mixture was prepared by introducing a controlled stream of sodium vapor into zinc vapor generated in a heat‐pipe oven. A new band (bound–free transition) was observed in the region from 450 to 487 nm. Potential curves of the eight lowest electronic states of NaZn were calculated. On the basis of the calculations, the observed emission is interpreted as resulting from the 2 2Π–X 2Σ+ transition. The conditions favorable for the observation of the photochemical reaction are discussed.
12 citations
TL;DR: In this paper, the bound-bound and bound-free part of the 7Li2 21 Σ� +>>\s transition has been studied both experimentally and by performing spectral simulations.
Abstract: The7Li2 21 Σ
+
→X
1 Σ
+
electronic transition has a bound-bound and a bound-free part due to the double minimum nature of the upper 21 Σ
+
state. We have studied this transition both experimentally and by performing spectral simulations. When inner well was excited the bound-free part at 4525 A was observed due to the collisions between Li
2
*
and argon. We found that when levels above the barrier are excited the bound-free emission is strongly affected by collisional relaxation of Li
2
*
by Li atoms. Conditions for the observation of the bound-free part are discussed.
1 citations
31 Dec 1993
TL;DR: It is expected that pulsed laser polymerization could improve the conversion rate, decrease a temperature rise in the sample, allowing the `cooling' of the material and reduce polymerization shrinkage.
Abstract: The aim of the investigation was to improve the quality of the cured composite resin using the pulsedlaser, thus avoiding disadvantages of previously used methods. The light source consisted of the pumpexcimer laser (Lambda Physik LPX 100) and the dye laser (Lambda Physik 3000). It is expected thatpulsed laser polymerization could improve the conversion rate, decrease a temperature rise in the sample,allowing the "cooling" ofthe material and reduce polymerization shrinkage.1. INTRODUCTION Photocurable composite resins are of indispensable import in modem esthetic denlistry. The advantages of these over chemically cured resins are as follows: longer working time, less porosity, bettercolor stability and physical properties. 2 The composition ofphotoactivated resins differ from the conventional materials only in the activators andinitiators. They contain camphorquinone in combinations with N, N—dimethylaminoethyl-methacrylat, asphotocheniical initiators. The camphorquinone is activated by wavelengths in the blue region ofthe visiblespectrum which means in the range of400-500 am.The success of a visible hghtcured composite restorations depends on the capability of the visible