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Relevance. The engineering and technical service of an agricultural enterprise is a separate subdivision of the management system of the farm, consisting of engineering and technical personnel providing a regulated procedure for the implementation of measures aimed at maintaining the machine and tractor fleet in working condition and ensuring its high-performance operation.Methods. To solve the goal set in the work, studies were conducted in which various materials and methods were used: information and communication technologies, online platforms, a large amount of data was analyzed characterizing the possibilities of creating a recycling system in the agro-industrial complex of the Tambov region, based on the state of the machine-tractor fleet of the agro-industrial complex, its age characteristics and the capabilities of the enterprises of the engineering structure of the agro-industrial complex to carry out this kind of activity. The information received was processed using statistical analysis methods.Results. The actual problems are identified and new approaches to the modernization of the engineering service of the agro-industrial complex for the region are identified, taking into account the goals and objectives of the Government of the Russian Federation. Prospects for further development and optimization of the engineering and technical service of the region are proposed. The possibility of creating an engineering service of workshops (sites) for the collection, processing, monitoring and disposal of decommissioned equipment in the structure of existing repair and technical enterprises (RTP) is evaluated. The evidence base of the expediency of creating an additional production structure within the framework of the RTP for the collection, processing, monitoring and disposal of equipment is presented. As the analysis has shown, there is a clear need to improve the system of engineering enterprises in the field of MTP operation.

The paper is devoted to the analysis of the state of the equipment recycling system in Russia and the issues of improving the legislative framework that accompanies it. The role of state structures in solving the problems of forming a resource-saving ecooriented system for the disposal of decommissioned equipment is reflected. To analyze the work in the field of waste management, to reflect the state of the legislative framework for the existing system of recycling equipment in Russia and abroad, to make recommendations for its improvement. Problems with waste appear when, in the process of production and consumption of substances, objects (equipment), he/she becomes unnecessary for their owners, their owner tries to get rid of this object in the most accessible way. According to numerous information, the disposal of equipment in Russia is mainly carried out (black waste collectors), which control more than 60 % of the scrap of non-ferrous and ferrous metals, so the solution to the problem of creating an effective system for the disposal of equipment becomes not just relevant, but vital for our state. The scientific community in Russia is constantly conducting research on the creation and implementation of a system for the disposal of decommissioned equipment, so, for example, MADI scientists proposed a regional car recycling system for implementation, the scientists of the Federal State Budgetary Educational Institution FNAC VIM also developed a regional system for the disposal of agricultural recycling equipment. In order to quickly solve the problem of working out a general strategy for creating an effective system of recycling equipment in Russia, taking into account the revision of the legislative framework, it is advisable to "run-in" it at the industry level, for example, in the agroindustrial complex, with subsequent replication in other industries.

We consider thermo-optic hysteresis in a silicon structure supporting bound state in the continuum. Taking into account radiative heat transfer as a major cooling mechanism we constructed a non-linear model describing the optical response. It is shown that the thermo-optic hysteresis can be obtained with low intensities of incident light $I_0\approx 1~\rm{W/m^2}$ at the red edge of the visible under the critical coupling condition.

The state of the repair and maintenance facilities operating within Russia’s agro-industrial complex is reviewed. The existing stock of agricultural machinery is analyzed. Measures to improve the efficiency of such repair and maintenance facilities are proposed.

The problem of renewing the fleet of agricultural machinery in the agricultural sector of the Russian Federation along with the disposal of these machines is discussed.

The article presents the results of analysis and research on the state of the engineering service of the agro-industrial complex, as well as the analysis of the "Strategy for the development of agricultural engineering in Russia for the period up to 2030" from the standpoint of its eff ectiveness in providing the agro-industrial complex of the Russian Federation with the necessary amount of agricultural machinery. Assess the actual state of the agricultural machine-building industry and the needs of the Russian Federation agro-industrial complex in updating the machine park. To substantiate the organizational and technological models for maintaining the performance of agricultural machinery, primarily energy-rich, in modern operating conditions using new technologies. The analysis of publications of domestic and foreign authors, refl ecting the state of the engineering service of the agroindustrial complex. The factors that determine the choice of an organizational and technological model for maintaining the operability of equipment in relation to the conditions of the agro-industrial complex of Russia are investigated. Received and processed statistical information on the current state of the equipment park and enterprises of the repair and service base of the agro-industrial complex. Based on the results of the study, the state of the fl eet of agricultural machinery used was determined, as well as the ability of the repair and maintenance base of the agro-industrial complex to ensure its performance. The results of the study showed that the implementation of the positive capabilities of various life support systems of equipment and systems for maintenance and repair is hampered by the unstable position of participants in the processes of production, use and renovation of equipment. It was also revealed that the fl eet of equipment is outdated, requires large volumes of maintenance and repair, and the repair and maintenance base of the agro-industrial complex in Russia as a whole is not able to fulfi ll the tasks of providing the necessary level of technical assistance when using agricultural machinery

In the agro-industrial complex of Russia, the share of the main types of agricultural machinery with a service life of more than 10 years is: for tractors — 61 %, grain harvesters — 47, forage harvesters — 42 %. Due to the extremely low provision of the Russian agro-industrial complex with modern tractors, the energy supply per 100 hectares of sown area is 150 hp. with technologically required 300–350 hp. On cattle farms, the level of complex mechanization of technological processes has decreased by 23 . Within the standard period, no more than 20–25 % of technological equipment is used and only 5–8 % meet modern requirements. The problem of updating the park of domestic agricultural machinery and livestock equipment can be considered only in a single complex with the disposal of these machines and equipment.

According to forecasts for 2022, the number of self-propelled agricultural equipment that will fail will be about 100 thousand units. This will have a fairly noticeable effect on overall agricultural productivity. The paper analyzes the main technological aspects of the possibility of creating a unit (section) for the utilization of agricultural machinery, taking into account the standards of a typical enterprise for technical service. The presented recommendations enable specialized enterprises engaged in the disposal of equipment to quickly carry out work on the creation of a unit (section) for recycling machines, which will make it possible to maximize the production of secondary resources from recycled waste of agricultural machines.

The article presents the results of studies aimed at determining the criterion for the further use of agricultural machinery that has reached the limit state: to carry out major repairs or dispose of it, as much as possible to save material resources, as required by the principles of the circular economy. Analysis and review of the works of domestic and foreign scientists, as well as the results of studies to identify the reasons for the lack of an effective mechanism for determining the limit state of a particular agricultural machine and the criterion for the onset of this condition. To solve the tasks, the technical condition and cost of the components included in the equipment supplied to the repair enterprises of the industry in 12 regions of Russia were studied. Was determined based on changes in the structure of parts with different periods of use of agricultural machinery. The results showed that the price of repair of the machine depends on the level of loss of validity of its parts, which were divided into three groups: fit without repair, fit after recovery and scrap, which cannot be restored. Was built based on the prices of capital repair machines and revenue from the sale of components utilized machine when the loss of her life, which allowed to determine the boundaries for further use of the machine, which reached a limit state. It was found that the loss of shelf life of almost all machines now entering the repair facility, is beyond the limits of the state and must be disposed of. The limit state of the machine occurs when the loss of its validity in the range of 0.45 < Г[sub]п∑i[/sub] < 0.5. In this interval, the owner of the machine can choose either of two options for its further use: repair or recycle. When Г[sub]п∑i[/sub] of 0.5 will require disposal, which will provides the greatest possible resource efficiency. An analysis of the research, taking into account past and foreign experience, will justify the direction of the agricultural sector in maintaining high technical readiness of agricultural machinery.

To date, scientists have formulated the structure of the agro-industrial complex (APC) of Russia, which is adhered to by most researchers. This structure is interpreted as a model of four spheres. The fi rst is a collection of industries specializing in agricultural production. This also includes construction in the agricultural sector and its logistics. The second area is agricultural production itself, and the third is the industries associated with the storage, sale, processing, etc. The Russian APC also includes activities that have not entered any of the spheres. This is, for example, special agricultural science, management, training, etc. Determining the trend of the development of the engineering and technical system of the Russian APC, both in the pre-perestroika period, and at present, considering the domestic and foreign experience. Agricultural machinery is the locomotive of the agricultural sector, the improvement of which determines the structure of agricultural producers. Its constant development and application for agricultural work ultimately determines not only the technology of agricultural work, but also the social way of the rural population. It was the improvement of agricultural machinery that served to stratify the social situation of the peasantry, which was originally the owners of small plots of land. In recent years, the main direction of the development of technology is to increase its capacity and productivity, in the calculation of processing large areas, which does not always coincide with the needs of farmers. Despite the progress, a large part of agricultural producers works in very limited areas, which often aff ects the priority demand for the equipment of the previous generation. As a result of the research, the following basic principles of the key areas of the Agricultural Sector can be formulated: agriculture is an economic sector aimed at providing food (food, raw materials) and is a donor for other sectors of the economy, a source of replenishment of national income for solving the urgent problems of the country. At present, the eff ectiveness of Russia’s APC is signifi cantly lower than in the leading countries and it is important not only to analyze the existing problems, but also to consider options for changing the current situation; the main engine of agricultural development is agricultural machinery, which forms the potential of agricultural production. This capacity depends on the level of technical support for the industry with machines and equipment for agricultural work of a wide range. Consideration and analysis of the possibility of raising this level considering the national specifi cs of Russia and international experience of industrial development, including agricultural engineering, is also a very important task (Conclusions) according to the authors, TST is an integral and important element of agricultural engineering, and, therefore, the core element of the Agricultural Sector. Analysis of this element, considering past experience, as well as new domestic and foreign developments, will justify the direction of modernization of the TST taking into account the national mentality.

The article presents the results of research and analytical reviews to determine the possibilities of using digital technologies in the disposal of decommissioned agricultural equipment. The rationale for the use of digital technology in the formation of a resource-saving eco-friendly system for the disposal of agricultural machinery. Until recently, technical support for equipment manufacturers ended with the operation phase. The requirements of regulatory documents on the need to dispose of decommissioned equipment in design, operational and repair regulatory documents were purely declarative in nature and have not been (and are not yet implemented in Russia) by its manufacturers. he use of CALS (IPI) — technologies for the formation of a system for utilization of agricultural machinery will create a common database that will be based on the fi nal state of parts and their variable properties. Also, their application will make it possible to provide logistic support for all components of the material fl ows of equipment throughout the life cycle. In addition, the use of common software aimed at performing these functions will create the necessary conditions for the operation and maintenance of the functionality of the system. The most optimal option is to create VET utilization systems taking into account the national peculiarities of Russia on the basis of existing foreign developments both for creating operational and repair documents in digital format, and for developing technologies for utilization of equipment that take into account the requirements of resource conservation and the environment.

The article is a study of development options for domestic agricultural machinery in the field of competitiveness.

The Brownian dynamics method is employed to study the formation of an electrical double layer (EDL) on the metal nanoparticle (NP) surface in hydrosols during adsorption of electrolyte ions from the interparticle medium. Also studied is the charge accumulation by NPs in the Stern layer. To simulate the process of the formation of EDL, we took into account the effect of image forces and specific adsorption, dissipative and random forces, and the degree of hydration of adsorbed ions on the EDL structure. The employed model makes it possible to determine the charge of NPs and the structure of EDL. For the first time, the charge of both the diffuse part of EDL and the dense Stern layer has been determined. A decrease in the electrolyte concentration (below c

Mostly forsaken, but revived after the emergence of all-dielectric nanophotonics, the Kerker effect can be observed in a variety of nanostructures from high-index constituents with strong electric and magnetic Mie resonances. A necessary requirement for the existence of a magnetic response limits the use of generally nonmagnetic conventional plasmonic nanostructures for the Kerker effect. In spite of this, we demonstrate here the emergence of the lattice Kerker effect in regular plasmonic Al nanostructures. Collective lattice oscillations emerging from the delicate interplay between Rayleigh anomalies and localized surface plasmon resonances both of electric and magnetic dipoles, and electric and magnetic quadrupoles result in suppression of the backscattering in a broad spectral range. Variation of geometrical parameters of Al arrays allows for tailoring the lattice Kerker effect throughout UV and visible wavelength ranges, which is close to impossible to achieve using other plasmonic or all-dielectric materials. It is argued that our results set the ground for wide ramifications in the plasmonics and further application of the Kerker effect.

The model of pairwise elastic repulsion of contacting colloidal nanoparticles with a rigid core and deformable shell is discussed. A simple analytical equation is applied for the energy of elastic repulsion of nanoparticles with arbitrary sizes and the elasticity moduli of self-healing polymer adsorption layers. The model is based on the representation of the absorption layer as a continuous medium that is elastically deformed upon the contact of nanoparticles. The major characteristic of this medium is the elasticity modulus. The magnitude of the elasticity modulus is determined from the condition of balance of the van der Waals attractive forces of nanoparticles and the elastic repulsion of their adsorption layers in the contact area, taking into account the temperature variations. We employed the kinetic approach to describe the dependence of the elasticity modulus on both the temperature and the rate of its change.

We propose to utilize titanium nitride (TiN) as an alternative material for linear periodic chains (LPCs) of nanoparticles (NPs) which support surface plasmon polariton (SPP) propagation. Dispersion and transmission properties of LPCs have been examined within the framework of the dipole approximation for NPs with various shapes: spheres, prolate and oblate spheroids. It is shown that LPCs of TiN NPs support high-Q eigenmodes for an SPP attenuation that is comparable with LPCs from conventional plasmonic materials such as Au or Ag, with the advantage that the refractory properties and cheap fabrication of TiN nanostructures are more preferable in practical implementations compared to Au and Ag. We show that the SPP decay in TiN LPCs remains almost the same even at extremely high temperatures which is impossible to reach with conventional plasmonic materials. Finally, we show that the bandwidth of TiN LPCs from non-spherical particles can be tuned from the visible to the telecommunication wavelength range by switching the SPP polarization, which is an attractive feature for integrating these structures into modern photonic devices.

We have established numerically the physical pattern and conditions for formation of nanosized bubbles in aqueous medium around biocompatible plasmonic nanoparticles (NPs) selectively bound to the membrane of the malignant cells by means of DNA-aptamers under the action of picosecond laser radiation. The results obtained are based on the finite volume method and hydrodynamic models underlying the ANSYS Fluent package with extended capabilities. We have found the main features and previously unknown dominant factors of the damage effect on the cell membrane at the moment of the bubble nucleation around the plasmonic NPs of different types taking into account the influence of the closely located membrane. Information on the kinetics of spatial distribution of pressure, temperature and the relative proportion of vapor in the ‘nanoparticle-membrane-medium’ system have been obtained. The attention is drawn to the advantages of using biocompatible, perfectly absorbing core–shell plasmonic NPs for anti-tumor therapy characterized by an increased mechanical effect on malignant cell membranes at lower laser radiation intensity and the spectral position of their plasmon resonance (λ = 700 nm) in the hemoglobin transparency range. This ensures penetration of laser radiation deep into tissues. The paper is provided with an extensive review of key publications and the state-of-art in this area.

We numerically investigate the conditions for the laser-induced formation of nanobubbles in aqueous medium around plasmonic nanoparticles (NPs) bound to the malignant cell membranes that is considered as the method of their irreversible damage. We proposed employing the versatile and accessible simulation software as a research tool based on the finite volume method underlying the ANSYS Fluent package and supplemented with our user-defined functions that adapt it to solution of the stated problems. This adaptation allows to verify the model using experimental data for the same conditions. We determined the conditions for the pressure growth on the cell membrane at the initial moment of bubble formation significantly exceeding the threshold of irreversible damage. The model can be used for investigation of hydrodynamic effects accompanying irradiation of plasmonic NPs using both different types of pulsed lasers and ideally absorbing NPs with resonance in the hemoglobin spectral transparency range, as well as to uncover previously unknown effects. They include the conditions for localization of a damaging factor non-affecting the normal cells, the conditions for generation of ultrahigh pressure pulse that enables to damage the cell membrane and precedes formation of thin vapor shell around NPs, which, unlike large bubbles, requires registration using highly sensitive experimental measurements. An extensive overview of key publications summarizing the state-of-art in this area is presented.

The paper presents the problems of forming a system of utilization of equipment in various sectors of the national economy, as well as ways to solve them. The problem of waste management in the agro-industrial complex is one of the key environmental problems due to the fact that waste, as a rule, contains secondary resources - useful substances and materials, the irrational use of which significantly affects their economic efficiency. In the country’s agriculture, this issue is especially acute, since the agro-industrial complex solves the problem of the country’s food security. The developed system of functioning of the technical potential of the agro-industrial complex makes it possible to reduce violations of environmental safety in production, namely: pollution of land, atmospheric air, water bodies, damage (destruction) of green deposition and other types of environmental damage.

Light trapping is a crucial prominence to improve the efficiency in thin film solar cells. However, last few years, plasmonic based thin film solar cells shows potential structure to improve efficiency in photovoltaics. In order to achieve the high efficiency in plasmonic based thin film solar cells, traditionally noble metals like Silver (Ag) and Gold (Au) are extensively used due to their ability to localize the light in nanoscale structures. In this paper, we numerically demonstrated the absorption enhancement due to the incorporation of novel plasmonic TiN nanoparticles on thin film Silicon Solar cells. Absorption enhancement significantly affected by TiN plasmonic nanoparticles on thin film silicon was studied using Finite-Difference-Time-Domain Method (FDTD). The optimal absorption enhancement 1.2 was achieved for TiN nanoparticles with the diameter of 100 nm. The results show that the plasmonic effect significantly dominant to achieve maximum absorption enhancement g ( λ ) at longer wavelengths (red and near infrared) and as comparable with Au nanoparticle on thin film Silicon. The absorption enhancement can be tuned to the desired position of solar spectrum by adjusting the size of TiN nanoparticles. Effect of nanoparticle diameters on the absorption enhancement was also thoroughly analyzed. The numerically simulated results show that TiN can play the similar role as gold nanoparticles on thin film silicon solar cells. Furthermore, TiN plasmonic material is cheap, abundant and more Complementary Metal Oxide Semiconductor (CMOS) compatible material than traditional plasmonic metals like Ag and Au, which can be easy integration with other optoelectronic devices.

We have studied thermal effects occurring during excitation of optical plasmonic waveguide (OPW) in the form of linear chain of spherical Ag nanoparticles by pulsed laser radiation. It was shown that heating and subsequent melting of the first irradiated particle in a chain can significantly deteriorate the transmission efficiency of OPW that is the crucial and limiting factor and continuous operation of OPW requires cooling devices. This effect is caused by suppression of particle's surface plasmon resonance due to reaching the melting point temperature. We have determined optimal excitation parameters which do not significantly affect the transmission efficiency of OPW.

Collective lattice resonances (CLRs) in finite-sized $ 2D $2D arrays of dielectric nanospheres have been studied via the coupled dipole approximation. We show that even for sufficiently large arrays, up to $ 100 \times 100 $100×100 nanoparticles (NPs), electric or magnetic dipole CLRs may differ significantly from the ones calculated for infinite arrays with the same NP sizes and interparticle distances. The discrepancy is explained by the existence of a sufficiently strong cross-interaction between electric and magnetic dipoles induced at NPs in finite-sized lattices, which is ignored for infinite arrays. We support this claim numerically and propose an analytic model to estimate a spectral width of CLRs for finite-sized arrays. Given that most of the current theoretical and numerical researches on collective effects in arrays of dielectric NPs rely on modeling infinite structures, the reported findings may contribute to thoughtful and optimal design of inherently finite-sized photonic devices.

Surface lattice resonances (SLRs) emerging in regular arrays of plasmonic nanoparticles (NPs) are known to be exceptionally sensitive to the homogeneity of the environment. It is considered necessary to have a homogeneous environment for engineering narrowband SLRs, while in a half-space environment, SLRs rapidly vanish as the contrast between the refractive indices of the substrate and superstrate increases. From this conventional wisdom, it is apparent that the delicate lattice Kerker effect emerging from SLRs and resonances on constituent NPs should be difficult to achieve in a non-homogeneous environment. Using a rigorous theoretical treatment with multipolar decomposition, we surprisingly find and explain a narrowband substrate-mediated lattice Kerker effect in two-dimensional arrays of Al nanocylinders in a half-space geometry. We propose to use this effect for sensing applications and demonstrate its broad tunability across the UV/Vis wavelength range.

Collective lattice resonances in regular arrays of plasmonic nanoparticles have attracted much attention due to a large number of applications in optics and photonics. Most of the research in this field is concentrated on the electric dipolar lattice resonances, leaving higher-order multipolar lattice resonances in plasmonic nanostructures relatively unexplored. Just a few works report exceptionally high-Q multipolar lattice resonances in plasmonic arrays, but only with infinite extent (i.e., perfectly periodic). In this work, we comprehensively study multipolar collective lattice resonances both in finite and in infinite arrays of Au and Al plasmonic nanoparticles using a rigorous theoretical treatment. It is shown that multipolar lattice resonances in the relatively large (up to 6400 nanoparticles) finite arrays exhibit broader full width at half maximum (FWHM) compared to similar resonances in the infinite arrays. We argue that our results are of particular importance for the practical implementation of multipolar lattice resonances in different photonics applications.

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала. Selective action of laser radiation on membranes of malignant cells has been studied in different regimes using conjugates of gold nanoparticles with oligonucleotides by the example of DNA aptamers. Under the conditions of a contact between a bioconjugate and a cell surface and the development of substantial and rapidly relaxing temperature gradients near a nanoparticle, the membranes of malignant cells alone are efficiently damaged due to the local hyperthermia of a cellular membrane. It has been shown that employment of pulsed instead of continuous wave laser radiation provides the localization of the damaging action, which does not involve healthy cells.

Charge transfer plasmons (CTPs) that occur in different topology and dimensionality arrays of metallic nanoparticles (NPs) linked by narrow molecular bridges are studied. The occurrence of CTPs in such arrays is related to the ballistic motion of electrons in thin linkers with the conductivity that is purely imaginary, in contrast to the case of conventional CTPs, where metallic NPs are linked by thick bridges with the real optical conductivity caused by carrier scattering. An original hybrid model for describing the CTPs with such linkers has been further developed. For different NP arrays, either a general analytical expression or a numerical solution has been obtained for the CTP frequencies. It has been shown that the CTP frequencies lie in the IR spectral range and depend on both the linker conductivity and the system geometry. It is found that the electron currents of plasmon oscillations correspond to minor charge displacements of only few electrons. It has been established that the interaction of the CTPs with an external electromagnetic field strongly depends on the symmetry of the electron currents in the linkers, which, in turn, are fully governed by the symmetry of the investigated system. The extended model and the analytical expressions for the CTPs frequencies have been compared with the conventional finite difference time domain simulations. It is argued that applications of this novel type of plasmon may have wide ramifications in the area of chemical sensing.

We consider refractive index sensing with optical bounds states in the continuum (BICs) in dielectric gratings. Applying a perturbative approach we derived the differential sensitivity and the figure of merit of a sensor operating in the spectral vicinity of a BIC. Optimisation design approach for engineering an effective sensor is proposed. An analytic formula for the maximal sensitivity with an optical BIC is derived. The results are supplied with straightforward numerical simulations.

The mechanisms of coupling between the lattice modes of a two-dimensional (2D) array consisting of Al nanoparticles and the localized modes of individual Al nanoparticles have been studied in detail. The results were obtained employing the finite-difference time-domain method (FDTD) and the generalized Mie theory. It was shown that interactions of single particles with 2D lattice modes significantly change the extinction spectra depending on the particle radius and the lattice period. The Rayleigh anomalies of higher orders contribute to formation of hybrid modes resulting in increase of the extinction efficiency in short wavelength range of the spectrum. It was shown that high intensity magnetic modes are excited in aluminum nanoparticles arrays. The patterns of spatial electromagnetic field distribution at the frequencies of hybrid modes have been studied. We note that comprehensive understanding the mode coupling mechanisms in arrays paves the way for engineering different types of modern photonic devices with controllable optical properties.

Collective lattice resonances (CLRs) emerging under oblique incidence in 2D finite-size arrays of Si nanospheres have been studied with the coupled dipole model. We show that hybridization between the Mie resonances localized on a single nanoparticle and angle-dependent grating Wood&ndash, Rayleigh anomalies allows for the efficient tuning of CLRs across the visible spectrum. Complex nature of CLRs in arrays of dielectric particles with both electric dipole (ED) and magnetic dipole (MD) resonances paves a way for a selective and flexible tuning of either ED or MD CLR by an appropriate variation of the angle of incidence. The importance of the finite-size effects, which are especially pronounced for CLRs emerging for high diffraction orders under an oblique incidence has been also discussed.

We have studied the dynamic and static processes occurring in disordered multiparticle colloidal Ag aggregates with natural structure and affecting their plasmonic absorption spectra under pico- and nanosecond pulsed laser radiations, as well as the physical origin responsible for these processes. We have shown that depending on the duration of the laser pulse, the mechanisms of laser modification of such aggregates can be associated both with changes in the resonant properties of the particles due to their heating and melting (picosecond irradiation mode) and with the particle shifts in the resonant domains of the aggregates (nanosecond pulses) which depend on the wavelength, intensity, and polarization of the radiation. These mechanisms result in formation of a narrow dip in the plasmonic absorption spectrum of the aggregates near the laser radiation wavelength and affect the shape and position of the dip. The effect of polydispersity of nanoparticle aggregates on laser photochromic reaction has been studied.

We present the theoretical model to predict the spectral position of Rayleigh anomalies emerged in hybrid system consisting of periodic array of plasmonic nanodisks embeded into the middle of defect layer of 1D photonic crystal (PhC). The spectral positions of these new emerged Rayleigh anomalies agree well with the results of exact simulations with Finite-Difference Time-Domain (FDTD) method.

We show that periodic structures from refractory titanium nitride (TiN) nanodiscs can support high-Q surface lattice resonances at telecom wavelengths. The obtained data open new prospects for utilization of TiN nanoparticles in next generation of photonics interconnects operating at high temperatures.

We have shown significant suppression of resonant properties of metallic nanoparticles at the surface plasmon frequency during the phase transition “solid–liquid” in the basic materials of nanoplasmonics (Ag, Au). Using experimental values of the optical constants of liquid and solid metals, we have calculated nanoparticle plasmonic absorption spectra. The effect was demonstrated for single particles, dimers and trimers, as well as for the large multiparticle colloidal aggregates. Experimental verification was performed for single Au nanoparticles heated to the melting temperature and above up to full suppression of the surface plasmon resonance. It is emphasized that this effect may underlie the nonlinear optical response of composite materials containing plasmonic nanoparticles and their aggregates.

New type of highly absorbing core-shell AZO/Au (aluminum doped zinc oxide/gold) and GZO/Au (gallium doped zinc oxide/gold) nanoparticles have been proposed for hyperthermia of malignant cells purposes. Comparative studies of pulsed laser hyperthermia were performed for Au nanoshells with AZO core and traditional SiO2 (quartz) core. We show that under the same conditions, the hyperthermia efficiency in the case of AZO increases by several orders of magnitude compared to SiO2 due to low heat capacity of AZO. Similar results have been obtained for GZO core which has same heat capacity. Calculations for pico-, nano- and sub-microsecond pulses demonstrate that reduced pulse duration results in strong spatial localization of overheated areas around nanoparticles, which ensures the absence of negative effects to the normal tissue. Moreover, we propose new alternative way for the optimization of hyperthermia efficiency: instead of maximizing the absorption of nanoparticles, we enhance the thermal damage effect on the membrane of malignant cell. This strategy allows to find the parameters of nanoparticle and the incident radiation for the most effective therapy.

The products of the reaction of cystamine dihydrochloride CystaH2Cl2 (Cysta is NH2(CH2)2SS(CH2)2NH2) with concentrated mineral acids (HBr, HClO4) and Zn(II), Co(II), or Cu(II) chlorides in 10 M HCl were synthesized and characterized. The compounds CystaH2Br2, CystaH2(ClO4)2, CystaH2[ZnCl4], CystaH2[CoCl4], and CystaH2[CuCl4] were obtained. The purity of the compounds was proved by X-ray diffraction, and the composition was determined from chemical and thermal analysis data. According to IR and Raman spectroscopy, all the compounds contain the cation.

Variations in the extinction spectra of aggregates of plasmon-resonant nanoparticles are studied at different stages of their planar deformation during interaction with dielectric substrates. Deformation and extinction spectra are calculated by the Brownian dynamics and coupled dipole methods, respectively. The effect of planar deformation of the aggregates on the pattern of the extinction contour in the range of the plasmon absorption band is analyzed by the example of aggregated silver hydrosols. It is shown that the extinction spectra of three-dimensional nanoparticle aggregates formed in bulk and those deformed upon deposition onto a substrate are markedly different. The calculation results are confirmed by experimental data.

The effect of defects such as vacancies, dislocations, and interstices on the extinction spectra of colloidal crystals consisting of plasmon resonance silver nanoparticles is investigated. The possibility of using extinction spectra for the express monitoring of individual and combined defects is discussed.

The effect of the temperature of a silver sol on its extinction spectra during formation of aggregates of plasmon resonance nanoparticles with varying degree of order and the effect exerted on these spectra by changes in the structure of a colloidal crystal during its heating, which lowers elastic properties of a polymer adsorption layer of particles are studied.

Changes in extinction spectra of nanostructured colloids of plasmon resonance particles are studied at different stages of their crystallization. The spontaneous crystallization is calculated by the method of Brownian dynamics, and the extinction spectra are calculated by the method of coupled dipoles. Based on the example of silver sols, we analyzed how separate parameters of the crystallizing disperse system affect the shape of the extinction contour in the plasmon absorption band.

Reasons for the appearance of defects of various types in crystalline colloidal structures formed during the self-organization of the ensembles of spherical nanoparticles are analyzed using lyosols of metal nanoparticles stabilized with polymers as examples. Quantitative characteristic of the degree of imperfection of colloidal crystals is proposed and the procedures for the minimization of the degree of imperfection are discussed. Order-disorder phase transitions of colloidal crystals are studied.

The kinetics of the formation of crystalline colloidal structures upon the self-organization of ensembles of spherical nanoparticles in model metal lyosols is studied by the Brownian dynamics using realistic potentials of interparticle interaction. The effect of single factors (parameters of dispersed phase particles and characteristics of dispersion medium), as well as their set and arbitrary combinations on the rate of crystallization of sols and regularities of this process are analyzed.

Regularities of the self-organization of ensembles of nanoparticles into crystalline structures in metal lyosols are studied by the Brownian dynamics. Van der Waals, elastic, and electrostatic interparticle interactions, as well as the action of dissipative and fluctuation forces are taken into account in the model. Pair interaction potentials for the polydisperse ensembles of particles are analyzed and the correlations between the pattern of potential curves and the type of formed structures (from crystalline to fractal) are revealed. The effect of interparticle tangential friction on the degree of ordering of formed structures is studied. It is demonstrated that this factor can determine the degree of ordering of nanoparticle aggregates. An essentially new approach to describing elastic interactions of nanoparticles of polymer-containing sols is implemented.

Regularities of the self-organization of bimodal ensembles of nanoparticles into crystalline structures in metal lyosols are studied by the Brownian dynamics method. Differences in the thicknesses of adsorption layers, van der Waals, elastic, and electrostatic interactions, and random and dissipative forces, as well as variations in interparticle electrostatic interactions due to electron tunneling are taken into account in the model. Pair potentials for polydisperse ensembles of particles are analyzed and the correlation between the pattern of potential curves and the type of forming structures is revealed. The possibility of the selective coagulation of particles with different sizes by virtue of dissimilar charging at the moment of their approach is demonstrated. The kinetics of this process is investigated. Specific features of the crystallization of bimodal sols are discussed using real gold organosols as examples.

Experimental data testifying in favor of the correlation between electrodynamic characteristics of fractal aggregates and the structure of the local environment of particles are discussed. One of the possible variants of the control of local structure of disordered silver nanoparticle aggregates placed into a polymer matrix via a significant decrease in its volume is proposed and realized. An indirect method for the detection of the variations in the local structure with the use of plasmon absorption spectra is proposed and substantiated. The evolution of local anisotropy of the environment of the particles of loose aggregates during their compaction is studied. Differences in the absorption spectra of silver nanoaggregates in hydrosols with various concentrations of water-soluble polymer that determine the properties of the local structure of aggregates are discussed, these differences being manifested upon the formation of fragments with quasi-ordered arrangement of particles and in the absence of such fragments.