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Nanocluster structures can be easily modified in necessary direction and by controlled way in femtonanophotonics experiments. The variation of the key topology parameters can result in new type of the quantum correlation states/size effect for charged particles. In our earlier experiments we studied laser-induced topological nanoclusters structures of different types in thin films with unique phenomena in electrophysics and optics (see [1-3]). A simple 2-steps mechanism for enhancement of quantum behavior (e.g. in electroconductivity) exists for different conditions. First, when inelastic length linelastic > acluster we have no incoherent electron-phonon (e-ph) scattering, i.e. the coherent process takes place. Second, when de Broglie wave length λdB ≡ ℓcoh < Λ, (acluster – cluster size , Λ – spatial period of nanoparticle distribution) the coherent tunneling without loss occurs, and a long-range order with interference of the states takes place in the medium due to lattice structure.

Purpose: to conduct a hydrochemical analysis and give a comprehensive eco-toxicological assessment of the Kacha river water. Materials and methods. The content of chemical components in surface water was determined using titrimetric and photocolorimetric analyses. The degree of surface water pollution was calculated using a comprehensive assessment method on individual hydrochemical indicators, calculating the combinatorial water pollution index. Algotesting was carried out by measuring the optical density of the chlorella microalgae culture (Chlorella vulgaris Beijer). For phytotesting the seeds of dicotyledonous plants – cucumber (Cucumis sativus L.), soya bean (Glycine max (L.) Merr.) and monocotyledonous plants – common oats (Avena sativa L.) were used. Test parameters: seed germination and germination readiness, root and sprout length were analyzed. Results. According to the hydrochemical parameters of the Kacha river, the waters were classified as oligohaline, and according to the specific combinatorial index (S′ = 1.15) they were classified as slightly polluted ones of the second class. The values of the coefficient of complexity of water contamination rate during 2012–2018 were within 12 %. In 2023, the Kacha river water was defined as moderately hard water (7.4 mg-eq/cubic dm), while a decrease in the average water salinity (566.1 mg/cubic dm) and an improvement in its quality in terms of total iron (0.12 mg/cubic dm) were noted, which corresponded to the maximum permissible concentration for water bodies of municipal and amenity water use significance. The water algoeffect reached 57 %, and the phytoeffect – 87 %. Conclusions. The use of biological methods – algotesting and phytotesting – showed the presence of toxicants in the Kacha river water from the effluent to the mouth. The need for additional control of the river water quality during its use, including irrigation, was noted.

We studied in both theory and experiment the nanocluster structures of different types (due to topology and composition) taking into account the correlations in nanoparticle-ensemble by quantum states. The problem of high temperature superconductivity due to topological surface structures with localized states has been under our consideration. Dramatic enhancement of electroconductivity (in six orders!), observed in our experiments, may be discussed as a real tendency to high temperature superconductivity due to topological peculiarities of nanocluster system. Near-field photoluminescence spectra/optical response in hybrid nanosystems measured by us demonstrated a big efficiency in the nanoantenna respect.

The nanostructures with different morphology have been obtained by us by methods of both direct laser modification (from cw to fs laser radiation) of the target surface/thin films and laser evaporation of the target substance in liquid to produce the colloid systems, and then – to deposite substance on substrate from colloid, and also – by a single drop deposition technique. The analysis of induced nanostructures has been carried out by absorption spectroscopy, scanning electron microscopy and transmission electron microscopy. The island conductivity is dominant for the nanocluster semiconductor systems induced by laser ablation technique, and electroresistance can dramatically decrease due to spontaneous selected multichannel/parallel electron transportation trajectories. A tunneling quantum coherent effect takes place for electron conductivity for the case.

Arrays of memristive devices coupled with photosensors can be used for capturing and processing visual information, thereby realizing the concept of “in-sensor computing”. This is a promising concept associated with the development of compact and low-power machine vision devices, which is crucial important for bionic prostheses of eyes, on-board image recognition systems for unmanned vehicles, computer vision in robotics, etc. This concept can be applied for the creation of a memristor based neuromorphic analog machine vision systems, and here, we propose a new architecture for these systems in which captured visual data are fed to a spiking artificial neural network (SNN) based on memristive devices without analog-to-digital and digital-to-analog conversions. Such an approach opens up the opportunities of creating more compact, energy-efficient visual processing units for wearable, on-board, and embedded electronics for such areas as robotics, the Internet of Things, and neuroprosthetics, as well as other practical applications in the field of artificial intelligence.

We develop a method for the laser synthesis and deposition of carbon–gold films formed by a net of linear sp-carbon chains and stabilized by gold nanoparticles. The originality of the method is in the simultaneous production of carbon chains and gold nanoparticles due to the laser fragmentation of the amorphous carbon and hydrogen tetrachloroaurate (III) or chloroauric acid. We study how surface resistivity alters the effect of the obtained films via the illumination in the visible spectral range.

We report on the fabrication of fractal dendrites using laser-induced melting of aluminum alloys. We target boron carbide (B4C), which is one of the most effective radiation-absorbing materials characterized by a low coefficient of thermal expansion. Due to the high fragility of B4C crystals, we were able to introduce its nanoparticles into a stabilization aluminum matrix of AA385.0. The high-intensity laser field action led to the formation of composite dendrite structures under the effect of local surface melting. Modelling the dendrite cluster growth confirms its fractal nature and sheds light on the pattern behavior of the resulting quasicrystal structure.

The formation of macroscale carbon structures characterised by an sp-sp2-hybridization is realised by self-assembly in colloidal solutions under an effect of laser irradiation and electromagnetic fields. The sponge-like morphology, sculptured with gold nanoparticles (NPs) was revealed by Scanning Electron Microscopy (SEM) imaging. Full structural and defect characterization of the self-assembled sponges was provided using the micro-Raman spectroscopic technique. The synthesized clusters manifest themselves in the presence of a strong spectral band in the visible range of the photoluminescence spectra that is quite unusual for ordered sp2-carbon systems.

Arrays of memristive devices coupled with photosensors can be used for capturing and processing visual information, thereby realizing the concept of "in-sensor computing". This is a promising concept associated with the development of compact and low-power machine vision devices, which is crucial important for bionic prostheses of eyes, on-board image recognition systems for unmanned vehicles, computer vision in robotics, etc. This concept can be applied for the creation of a memristor based neuromorphic analog machine vision systems, and here, we propose a new architecture for these systems in which captured visual data are fed to a spiking artificial neural network (SNN) based on memristive devices without analog-to-digital and digital-to-analog conversions. Such an approach opens up the opportunities of creating more compact, energy-efficient visual processing units for wearable, on-board, and embedded electronics for such areas as robotics, the Internet of Things, and neuroprosthetics, as well as other practical applications in the field of artificial intelligence. [ABSTRACT FROM AUTHOR]