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Using the technique of laser probing, the time dependences of the transparency factor, integral glow, and of the scattered component of probing radiation for erosional laser jets of metals exposed to intense submicrosecond laser pulses have been determined. Based on the results of laser probing, a conclusion on the condensation nature of the process of formation of a liquid-droplet phase of the target-material under the given conditions of laser action has been drawn.

621.373.8 Methods have been developed for the formation and characterization of an ultra-dispersed silver phase in polymeric matrices, specifically in polyvinyl alcohol films. A method for laser erosion of metals in air is proposed for production of silver nanoparticles. Polyvinyl alcohol films with silver nanoparticles can be obtained by implanting the particles in aqueous solutions of the film-forming material. A complex diagnostic method is recommended for investigation of the resulting polymeric films.Keywords: laser erosion of metals, single-wave laser probing, transmission electron microscopy, absorption spectroscopy, surface plasma resonance.Introduction. Nanotechnology has so deeply invaded our lives that it is now hard to imagine producing electronics, optics, and chemicals without using nanoscale items. Many advantages of nanostructured materials are due to the specific properties that they acquire upon reaching the dimensions (even if in one direction) of the order of tens of nanometers.Hence, the production and use of materials containing metal nanoparticles is exceedingly promising. Such metal nanoparticles exhibit a whole spectrum of properties (physical, chemical, biological) that distinguish them dramatically from bulk metals [1]. Polymeric matrices containing metal nanoparticles, in particular silver, provide an example of such a nanostructured material. The presence of a characteristic absorption band for Ag nanoparticles that is caused by a surface plasma resonance (SPR) effect enables such ultradispersed materials to be used as photoresistant optical filters.One promising method for forming Ag nanoparticles is laser erosion in air. This has been described in detail [2,3]. Herein we study the possibility of forming and investigating polymeric matrices containing embedded Ag nanoparticles that were produced by laser erosion in air under normal conditions.Experimental. Laser erosion of metals in air using submicrosecond pulses of high-power-density radiation was used to form the Ag nanoparticles. It was shown [4] that a significant number (10

We have used a combination of physical diagnostics methods (laser probe, absorption spectroscopy, transmission electron microscopy) to study an aqueous suspension of silver nanoparticles, formed by laser ablation of a metal target in the atmosphere. We have established that application of the methods described allows us to obtain the most complete information about the state of nanosized metal particles in optically transparent media.Key words: aqueous suspension of metal nanoparticles, laser ablation, laser probe, absorption spectroscopy, atomic force microscopy, transmission electron microscopy, surface plasmon resonance. Introduction.A direction in science and technology that has been very much in demand in recent years is associated with preparation of nanostructural materials and their adoption in various areas of the national economy. The range of potential applications of such materials is quite broad: from pharmaceuticals to electronics. Such interest in nanotechnologies is due to the specific properties of nanostructures. The range of potential applications of such materials is quite broad: from pharmaceutical science to electronics. Such interest in nanotechnologies is due to the specific properties of nanostructures. For example, the mechanical, electrical, magnetic, optical, and chemical properties of many metals change substantially on going to nanostructures.Depending on the goals for obtaining the metal nanoparticles, very different methods can be used: chemical reduction of metals in solutions of their salts [1], implantation of metal ions in a matrix [2], electrical discharge (spark [3] and arc [4]) between metal electrodes in liquids, laser ablation in liquid media [5] and in the atmosphere [6]. Accordingly, adequate measurement of such a critical parameter as the effective sizes of the nanosized particles obtained becomes more important.This work was devoted to study of the possibility of combining existing methods for diagnostics of smallsized metallic systems with the goal of obtaining reliable information on the presence of metal nanoparticles and their sizes in optically transparent media. As the object of study, we used an aqueous suspension of silver nanoparticles obtained by laser ablation of the metal in the atmosphere by exposure to single pulses of high-power laser radiation in the frequency mode.The Experiment. Preparation of the suspensions of silver nanoparticles (laser ablation in the atmosphere). As we know, when a metal is exposed to laser radiation of moderate power density (10

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