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In a previous paper, we have presented a new method to carry out the rotational temperature from the UV OH band at 306.357 nm (transition A²∑, ν = 0 → X⊃2 π, ν' = 0) frequently observed in hot gases containing oxygen and hydrogen (flames, arc plasmas). The method is mainly based on a calibration of the height of 3 unresolved groups of lines obtained by performing a numerical simulation of OH spectrum for different temperatures and for different widths of gaussian apparatus functions. In this paper, we underline that the apparatus function needed to carry out the temperature with the method described in the reference is not only the pure optical apparatus function of the optical spectroscopic device commonly measured by employing a laser line, but must include the broadening effects of the rotational Lines. At least, we propose a numerical method to determine a global apparatus function needed to apply the temperature determination method presented in the paper by de Izarra. [ABSTRACT FROM AUTHOR]

Carbamazepine (CBZ) is a pharmaceutical compound detected in various water resources. With a view to removing this contaminant, the applicability of non-thermal plasma (NTP) oxidation process has been widely tested in recent years. This study utilized NTP from a dielectric barrier discharge reactor in the treatment of CBZ. NTP on the surface of a water sample containing 25 mg.L -1 of CBZ resulted in a removal efficiency of over 90% with an energy yield of 0.19 g. (kWh) -1 . On the other hand, a rapid reduction in pH and an increase of conductivity and nitrate/nitrite ions concentration were observed during the degradation. The applied voltage amplitude significantly affected the removal efficiency and the energy yield as the degradation efficiency was 55%, 70%, and 72% respectively with an applied voltage of 8, 10, and 12 kV. The water matrices containing inorganic anions such as chloride and carbonate ions reduced the removal efficiency by scavenging the reactive species. Accordingly, a reduction in the removal efficiency was observed in tap water. The high-resolution mass spectrometry (HRMS) results revealed that both reactive oxygen and nitrogen species take part in the reaction process which yields many intermediate products including aromatic nitro-products. This study concluded that NTP can effectively degrade CBZ in both pure and tap water, but special attention must be paid to changes in the water quality parameters (pH, conductivity, and nitrate/nitrite ions) and the fate of nitro products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In this work, direct irradiation by a Ti:Sapphire (100 fs) femtosecond laser beam at third harmonic (266 nm), with a moderate repetition rate (50 and 1000 Hz), was used to create regular periodic nanostructures upon polystyrene (PS) thin films. Typical Low Spatial Frequency LIPSSs (LSFLs) were obtained for 50 Hz, as well as for 1 kHz, in cases of one spot zone, and also using a line scanning irradiation. Laser beam fluence, repetition rate, number of pulses (or irradiation time), and scan velocity were optimized to lead to the formation of various periodic nanostructures. It was found that the surface morphology of PS strongly depends on the accumulation of a high number of pulses (10 3 to 10 7 pulses) at low energy (1 to 20 µJ/pulse). Additionally, heating the substrate from room temperature up to 97 °C during the laser irradiation modified the ripples' morphology, particularly their amplitude enhancement from 12 nm (RT) to 20 nm. Scanning electron microscopy and atomic force microscopy were used to image the morphological features of the surface structures. Laser-beam scanning at a chosen speed allowed for the generation of well-resolved ripples on the polymer film and homogeneity over a large area.

We describe here a rapid and straightforward solvent-free method to access phenylthiazolo[5,4- b ]pyridines using a Nd-YAG laser NANO-NY81-10 ( λ = 355 nm, 10 Hz pulse frequency; 8 ns pulse duration). This newly presented method successfully brings several improvements to the laser assisted synthesis of N , S -heterocycles. We are able to provide a solvent-, metal- and base-free method with good yield and a substantial reduction in reaction time., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)