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One of the main problems of world energy at present and in the near future is the problem of energy conservation. The gradual depletion of fossil fuel reserves, rising energy prices, a noticeable deterioration of the environmental situation, the ever-increasing competition in the world markets for food products and industrial products and services make the problem of rational energy consumption even more acute.

For quantum-size particles of the InSb, PbS, HgSe, CdSe semiconductors, a model of competition of dimensional quantum restrictions and blocking with a single-electron current and Coulomb restriction, as well as heating electrons with an electric field of the light wave, is proposed. This made it possible to explain the highly multiplicity (up to two orders of order) of a change in photoconductivity observed in conditions of tunnel conductivity, and in the conditions of the confinement --- the absence of inter-zone and inter-level photoconductivity. The resonant current peaks of quantum conductivity observed on the V-I characteristics when irritating with light of any wavelength (in the interval of 0.4-1.2 μm) are reset or shifted towards smaller voltage values. The energy minimum of quanta recorded in this case is estimated as 100 meV. The results can be useful in resolving issues of application in uncooled IR detectors, including single-photon registration. Keywords: Quantum-size particle, dimensional quantification, one-electron current, single-photon process, inter-zone and intra-zone transitions, tunnel conductivity, Coulomb restriction, quantum conductivity.

The application of foamed polymers as one of the components of insulating coatings allows to solve the problems of energy saving and creation of optimal operating conditions for constructions. The systems of application of energy-efficient heat-insulating materials must consider both the particularities of the insulating materials and the functional orientation of the constructions. The implementation of the concept of seamless insulating coatings implies the achievement of thermal effect and reduction in air permeability both by means of the application of thermal insulation with low thermal conductivity and the minimization of junctions between separate elements of the insulating coating, which is achieved using elastic foamed polymers and, first of all, polyethylene foam. Construction of seamless insulating coatings creates practically impermeable heat, vapor, and water barriers along the outer perimeter of the insulated object. Multilayer products based on polyethylene foam represent a relatively new material—a fact that requires examination of their properties, as well as under various operating conditions, and development of a methodology for evaluation of the operational resistance of these materials in structures of different purposes, including cold conservation. The performed tests have shown that the compressive strength at 10% deformation is determined by the function of load application area and varies from 70 kPa during the test of cube samples of 10 × 10 × 10 in size to 260 kPa for areas exceeding 100 m2. The longitudinal tensile strength amounts to 80–92 kPa, and the strength of the weld seam is equal to 29–32 kPa. It has been established that the values of thermal conductivity of polyethylene foam with an average density of 18–20 kg/m3 amounts to 0.032–0.034 W/(m·K), diffusion moisture absorption is equal to 0.44 kg/m2 without a metallized coating and 0.37 kg/m2 with a metallized coating, water absorption after partial immersion in water for 24 h amounts to 0.013 kg/m2, water absorption by volume after complete water immersion for 28 days is equal to 0.96%. The material does not practically change its properties under conditions of long-term temperature alteration from −60 to +70 °C. The developed and implemented insulation systems for protective surfaces of framed construction objects, rubbhalls and frameless structures, floating floors, indoor ice rinks, and snow conservation systems are presented.

Based on the current-voltage characteristics of single colloidal QDs -InSb, -PbS, -HgSe, -CdSe quantum dots, on random samples statistically determined and investigated the mechanisms of barrier and ballistic tunneling, Coulomb confinement, quasi-periodic modulation of electron transport in the model of a deep extended potential well and depending on QDs size and de Broglie wavelength for the electron. The possibility of manifestation of Bloch oscillations has been experimentally confirmed. The parameters of all investigated processes were determined and tabulated. Keywords: Nanoparticle, quantum dot, dimensional quantization, quantum selection, barrier and ballistic tunneling, Coulomb confinement, Coulomb ladder, Bloch oscillations.

For colloidal quantum-size particles (QP) of narrow-gap semiconductors, in contrast to quantum dots of wide-gap CdSe, in QP-PbS there take place an anomalous temperature dependence of the photoluminescence intensity. Also, in the planar microstructure containing QP-InSb, long-wavelength radiation (more than 3 μm) and photoconductivity (over 20 μm) was observed. Under certain conditions, the radiation intensity and photoconductivity demonstrate a resonance maximum. The effects were explained in the model of a one-dimensional quantum oscillator, which energy substantially depends on the effective mass of its quasi-free electron. This leads to competition between the manifestations of long-wave radiation and photoluminescence, and hence, to the anomalous temperature dependence of photoluminescence. It is assumed that QP-InSb in a planar microstructure can be sources and receivers of terahertz radiation, which properties depend on the crystal structure of quantum-sized particles determined by the parameters of their synthesis. Keywords: quantum-dimensional particle, quantum dot, narrow-gap semiconductor, effective mass, Brillouin zone, dimensional quantization, quantum oscillator, photoluminescence, long-wavelength radiation.

Colloidal nanocrystals (quantum dots (QDs)) of mercury selenide have been synthesized and the effect of size quantization on their basic properties has been investigated. The current-voltage characteristics of single QDs (less than 10 nm) had features in the form of separate regular peaks and quasi-periodic current oscillations with voltage intervals (0.1-0.2) V. The observed features were explained in the models of size quantization and Bloch oscillations. The absorption spectra in the range up to 25 μm had eight certain peaks, including five --- interband and intraband transitions and three --- with energies (145-215) meV, which are explained as intraresonant. Calculations show that it is possible to have IR photosensitivity in the wavelength range up to 40 μm. Keywords: Colloidal synthesis, nanocrystal, quantum dot, mercury selenide, dimensional quantization, Bloch pulsations, electron transport, IR absorption, IR photosensitivity.

According to the current-voltage characteristics (CVC) and absorption spectra of colloidal quantum dots QD-InSb, -PbS, -HgSe on random samples, the manifestations of charge instability appear in the form of single current peaks and quasi-periodic deviations from the monotonic dependence of the CVC, are determined and studied. The results are explained by dimensional electron quantization in the model of a deep extended potential well and depending on the ratios of the quantization size and the de Broglie wavelength for an electron. It is assumed that the manifestation of Bloch oscillations has been experimentally confirmed. The data on the studied processes are determined and summarized in a table. Keywords: Quantum dot, nanocrystal, size quantization, quantum selection, Coulomb constraint, Bloch oscillations.