The development of the electronic industry, with the further miniaturization of electronic components and the use of new materials puts forward increasingly stringent requirements for the quality, reliability and competitiveness of products. All this, in turn, dictates the creation of new technologies and technological processes. The microprocessing laser technologies at R&D production facility "Istok" named after Shokin " for the period 2003-2018, a series of modern automated laser technological installations of the "Caravel" type was created on the basis of industrial lasers and laser systems based on copper vapors and precision three-coordinate tables. This equipment with the diameter of the processing light spot of 10–20 μm and the peak power density of 109-1011 W/cm2 allows for efficient and high quality processing of foil (0.01-0.2 mm) and thin-sheet (0.2-1 mm) metal and the large range of non-metallic materials of microwave products.
Aromaticity is one of fundamental characteristics of unsaturated organic molecules, which significantly determine chemical properties. By definition, aromatic molecules mast be cyclic, planar, have a complete conjugated π- electrons, and the number of π-electrons mast be 4n+2, where n is any integer number. Aromatic molecules are chemically very stable and have low reactive ability. In the contrary, anti-aromatic molecules, which have conjugated 4n π-electrons, highly unstable, preferably isomerize into aromatic composition, and demonstrate high chemical activity. In this paper, we study properties of typical aromatic and anti-aromatic compounds on the example of pentalene, phenylacetylene, and benzocyclobutadiene, and compare the change of their photochemical properties with changing the electric charge (under the single and double ionization). It was found that aromaticity of the molecules is really changing due to the loss of electrons. Dissociation reactions of pentalene, phenylacetylene and benzocyclobutadiene, as far as their cationic and dicationic forms were investigated. The effect of Coulomb repulsion in doubly ionized molecules also has been observed.
Studying the processes occurring in biological systems under irradiation is critically important for understanding the principles of working of biological systems. One of the main problems, which stimulate interest to the processes of photo-induced excitation and ionization of biomolecules, is the necessity of their identification by various mass spectrometry (MS) methods. While simple analysis of small molecules became a standard MS technique long time ago, recognition of large molecules, especially carbohydrates, is still a difficult problem, and requires sophisticated techniques and complicated computer analysis. Due to the large variety of substances in the samples, as far as the complexity of the processes occurring after excitation/ionization of the molecules, the recognition efficiency of MS technique in terms of carbohydrates is still not high enough. Additional theoretical and experimental analysis of ionization and dissociation processes in various kinds of polysaccharides, beginning from the simplest ones, is necessary. In our work, we extent previous theoretical and experimental studies of saccharides, and concentrate our attention to protonated glucose. In this article we paid the most attention to the cross-ring dissociation and water loss reactions due to their importance for identification of various isomers of hydrocarbon molecules (for example, distinguish α- and β-glucose).
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