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The results of the study of the distribution of biota in the soil cover of the Smolinsk and Novokostiantynivsk uranium mines in the Kirovohrad region are highlighted. The basis of the research methodology is a systematic approach, within which general scientific methods (data analysis and synthesis) were used – selection and identification of biota. In the conditions of environmental monitoring and growing anthropogenic pressure, there is a need for a more careful attitude to the environment and the detection of new risk factors. Man, as a subject of the biosphere, is influenced not only by natural environmental factors, but also by new ones created by man himself, thereby significantly changing the environment. This dependence determines the emergence of various environmental relations between all biotic and abiotic components of the biosphere. Intensive extraction of ore from exploited deposits depletes the raw material base of mining enterprises, most of which becomes waste, sludge, and pits are formed. As part of the rehabilitation of the mine territory, alluvial soil is often used, which has its own specific features in the conditions of growing technogenesis. It was found that the number of bacteria in all soil samples decreases due to the lack of organic substances and living conditions. Mycomycetes, as multifunctional components of the soil biota, are stress-tolerant according to the type of life strategy with economical use and redistribution of nutrients in sedimentary soil. Representatives of the genera Mucor sp., Penicillium sp., Alternaria sp., Cladosporium sp. are among the first settlers to appear on man-made soils, representatives of the latter are typical bioindicators of environmental pollution. The identified changes in the quantitative and qualitative composition of the mycobiota in the man-made soil of the studied samples are fundamental for further long-term monitoring of the state of the environment of the Kirovohrad region, as well as the possibility of making a forecast regarding the toxic effect of industrial emissions on the biota as a whole.

An important task in protecting the environment from tritium pollution is to find effective, simple, affordable, low-cost and low-energy methods for extracting tritium from large volumes of low- and intermediate-level aqueous solutions. The article presents new data on the influence of the octahedral component of the structure of layered silicates on the extraction of tritium from aqueous solutions obtained using research on an experimental stationary system on the example of the natural mineral hibsite. The possibility of using hibsite as a natural adsorbent of tritium is considered. The degree of adsorption of tritium from an aqueous solution and the effect of fractionation of hydrogen isotopes in the stationary system “HTO-hibsite” were estimated. The mechanism of tritium retention in the structure of the natural adsorbent is explained. Tritium extracted from tritiated water is distributed in the mineral matter between different structural positions – with the lowest binding energy in the HTO molecular form in surface adsorbed moisture (1 fraction), with slightly higher – in -OT ionic form in the structural positions of the mineral adsorbent (2 and 3 factions). Up to 39% of the total amount of tritium extracted from the aqueous solution is retained in hibsite in a surface adsorbed form. The predominant retention of polarized HTO molecules, compared to H2O molecules, near the mineral surface due to dynamic adsorption-desorption processes causes the effect of fractionation of hydrogen isotopes (α = 1.14). The exchange between the OH groups of the structural Al-hydroxyl layers of the mineral and the OT groups of tritiated water leads to the fixation of up to 55% of tritium in this form. New scientific results on the influence of structural and physicochemical properties of the studied mineral adsorbent on its ability to extract tritium from aqueous solutions and new data on the peculiarities of the mechanism of interfacial isotope-hydrogen exchange in a water-mineral system provide, together with the results of our previous studies, more effective development of methods for detritization of aqueous solutions.

The operation of the nuclear fuel complex is constantly accompanied by contamination of liquid industrial discharges with tritium. The problem of preventing such pollution is complicated by the fact that the pollutant component (tritium) is an integral part of the aqueous transport substance. Equally important is the need to purify deuterium water used in the nuclear industry from tritium and to increase the efficiency of tritium concentration technologies for further use. The use of the process of electroosmotic fractionation of hydrogen isotopes is proposed for purification of NPP process waters from tritium. In the isotopic molecule of tritiated or deuterium water (“HTO”, “DTO”), the covalent bond D – O and T – O is stronger than H – O, so it is possible to separate the hydrogen isotops by using the electroosmostic method in aqueous solution on composite mineral proton-conducting membranes. Such conductors can provide fractionation of hydrogen isotopes by proton exchange by tunneling or forwarding transport of ions in the process of electroosmosis under the influence of the applied electric field. In order to determine the possibility and efficiency of the electroosmotic process for fractionation of hydrogen isotopes in aqueous solution, we used a three-chamber electroosmotic cell with variable proton-conducting membranes made of mixtures of montmorillonite clay and zeolite (MCZ), montmorillonite and quartz sand (MQS), montmorillonit (MC) and saponite (SC) clays. The anode chambers were filled with electrolyte in the amount of 450–550 cm3, prepared from tritiated water, with a specific activity of 5,950 Bq·dm– 3 with the addition of anhydrous Na2CO3 salt. Under the influence of the electric field, electroosmotic filtration of the dissociated tritiated electrolyte through weakly permeable clay and composite membranes from the anode chamber to the cathode chamber was happening. At the same time, due to the proton conductivity of electroosmotic membranes with increasing strength and voltage of electric current, the alkalinity of the aqueous solution in the cathode chamber increased and the specific activity of tritium in the filtrate (catholyte) decreased by 14–26%. The method is protected by the Patent of Ukraine for a utility model.

Our previous study shows that the angle of linear polarization (AOLP) of solar radiation that is scattered from clouds at near-backscatter angles can be used to detect super-thin cirrus clouds over oceans. Such clouds are too thin to be sensed using any current passive satellite instruments that only measure light's total intensity, because of the uncertainty in surface reflection. In this report, we show that with a method similar to the super-thin cloud detection algorithm, dust aerosols may also be detected and differentiated from clouds. We also show that the degree of polarization of reflected light can be used for retrieving the optical depth of dust aerosols in the neighborhood of the backscatter angle, regardless of the reflecting surface conditions. This is a simple and robust algorithm, which could be used to survey dust aerosols over midlatitude and tropical oceans.

In recent years, there has been an impressive development of nanotechnology. This has resulted in the increasing release of nanomaterials (NM) into the environment, thereby causing the risk of an uncontrolled impact on living organisms, including plants. More studies indicated the biotoxic effect of NM on plants, including crops. The interaction of nanoparticles (NP) with food crops is extremely important as they are a link to the food chain. The objective of this study was to investigate the effect of negatively charged gold nanoparticles (-) AuNP (at two concentrations; 25 µg/mL or 50 µg/mL) on barley (Hordeum vulgare L.) root development. Morphological, histological and ultrastructural analyses (with the use of stereomicroscope, bright filed microscope and transmission electron microscope) revealed that regardless of the concentration, (-) AuNP did not enter into the plant body. However, the dose of (-) AuNP proved to be important for the plant’s response because different morphological, histological and ultrastructural changes were observed in the treated roots. The NP treatment caused: red root colouration, a local increase in the root diameter and a decreased formation of the root hair cells (on morphological level), damage to the rhizodermal cells, vacuolisation of the cortical cells, a detachment of the cell files between the cortical cells, atypical divisions of the cells, disorder of the meristem organisation (on the histological level), the appearance of periplasmic space, numerous vesicles and multivesicular bodies, electron-dense spots in cytoplasm, alterations in the structure of the mitochondria, breakdown of the tonoplast and the plasmalemma (on the ultrastructural level).

A laser technology for creating nanocomposites from alternating layers of albumin/collagen proteins with two types of single-walled carbon nanotubes (SWCNT) at concentrations of 0.001 and 0.01 wt.% was proposed. For this purpose, a setup with a diode laser (810 nm) and feedback system for controlling the temperature of the area affected by the radiation was developed. Raman spectroscopy was used to determine a decrease in the defectiveness of SWCNT with an increase in their concentration in the nanocomposite due to the formation of branched 3D networks with covalent bonds between nanotubes. It was revealed that adhesion of proteins to branched 3D networks from SWCNT occurred. The specific electrical conductivity of nanocomposites based on large SWCNT nanotubes was 3.2 and 4.3 S/m compared to that for nanocomposites based on small SWCNT with the same concentrations—1.1 and 1.8 S/m. An increase in the concentration and size of nanotubes provides higher porosity of nanocomposites. For small SWCNT-based nanocomposites, a significant number of mesopores up to 50 nm in size and the largest specific surface area and specific pore volume were found. Nanocomposites with small SWCNT (0.001 wt.%) provided the best cardiac fibroblast viability. Such technology can be potentially used to create bioelectronic components or scaffolds for heart tissue engineering.

The article is devoted to the study of losses in devices based on high-temperature superconductors of the 2nd generation. The complexity of the devices under study increases from a single rack coil to a winding assembled from several coils, and finally to an electric machine operating in generator mode. This is the way to experimentally study the behavior of 2nd generation high temperature superconductor (2G HTS) carrying a transport current in various conditions: self-field, external DC, and AC magnetic field. Attention is also paid to the losses in the winding during its operation from the inverter, which simulates the operating conditions in the motor mode of a propulsion system.

The classical stoichiometric oxidation of alcohols is an important tool in contemporary organic chemistry. However, it still requires huge modifications in order to comply with the principles of green chemistry. The use of toxic chemicals, hazardous organic solvents, and the large amounts of toxic wastes that result from the reactions are a few examples of the problems that must be solved. Nanogold alone or conjugated with palladium were supported on different carriers (SiO2, C) and investigated in order to evaluate their catalytic potential for environmentally friendly alcohol oxidation under solvent-free and base-free conditions in the presence H2O2 as a clean oxidant. We tested different levels of Au loading (0.1–1.2% wt.) and different active catalytic site forms (monometallic Au or bimetallic Au–Pd sites). This provided new insights on how the structure of the Au-dispersions affected their catalytic performance. Importantly, the examination of the catalytic performance of the resulting catalysts was oriented toward a broad scope of alcohols, including those that are the most resistant to oxidation—the primary aliphatic alcohols. Surprisingly, the studies proved that Au/SiO2 at a level of Au loading as low as 0.1% wt. appeared to be efficient and prospective catalytic system for the green oxidation of alcohol. Most importantly, the results revealed that 0.1% Au/SiO2 might be the catalyst of choice with a wide scope of utility in the green oxidation of various structurally different alcohols as well as the non-activated aliphatic ones.

Cloud-aerosol interaction is a key issue in the climate system, affecting the water cycle, the weather, and the total energy balance including the spatial and temporal distribution of latent heat release. Information on the vertical distribution of cloud droplet microphysics and thermodynamic phase as a function of temperature or height, can be correlated with details of the aerosol field to provide insight on how these particles are affecting cloud properties and their consequences to cloud lifetime, precipitation, water cycle, and general energy balance. Unfortunately, today's experimental methods still lack the observational tools that can characterize the true evolution of the cloud microphysical, spatial and temporal structure in the cloud droplet scale, and then link these characteristics to environmental factors and properties of the cloud condensation nuclei. Here we propose and demonstrate a new experimental approach (the cloud scanner instrument) that provides the microphysical information missed in current experiments and remote sensing options. Cloud scanner measurements can be performed from aircraft, ground, or satellite by scanning the side of the clouds from the base to the top, providing us with the unique opportunity of obtaining snapshots of the cloud droplet microphysical and thermodynamic states as a function of height and brightness temperature in clouds at several development stages. The brightness temperature profile of the cloud side can be directly associated with the thermodynamic phase of the droplets to provide information on the glaciation temperature as a function of different ambient conditions, aerosol concentration, and type. An aircraft prototype of the cloud scanner was built and flew in a field campaign in Brazil. The CLAIM-3D (3-Dimensional Cloud Aerosol Interaction Mission) satellite concept proposed here combines several techniques to simultaneously measure the vertical profile of cloud microphysics, thermodynamic phase, brightness temperature, and aerosol amount and type in the neighborhood of the clouds. The wide wavelength range, and the use of multi-angle polarization measurements proposed for this mission allow us to estimate the availability and characteristics of aerosol particles acting as cloud condensation nuclei, and their effects on the cloud microphysical structure. These results can provide unprecedented details on the response of cloud droplet microphysics to natural and anthropogenic aerosols in the size scale where the interaction really happens.

Cloud development, the onset of precipitation and the effect of aerosol on clouds depend on the structure of the cloud profiles of droplet size and phase. Aircraft measurements of cloud profiles are limited in their temporal and spatial extent. Satellites were used to observe cloud tops not cloud profiles with vertical profiles of precipitation-sized droplets anticipated from CloudSat. The recently proposed CLAIM-3D satellite mission (cloud aerosol interaction mission in 3-D) suggests to measure profiles of cloud microphysical properties by retrieving them from the solar and infrared radiation reflected or emitted from cloud sides. Inversion of measurements from the cloud sides requires rigorous understanding of the 3-dimentional (3-D) properties of clouds. Here we discuss the reflected sunlight from the cloud sides and top at two wavelengths: one nonabsorbing to solar radiation (0.67 μm) and one with liquid water efficient absorption of solar radiation (2.1 μm). In contrast to the plane-parallel approximation, a conventional approach to all current operational retrievals, 3-D radiative transfer is used for interpreting the observed reflectances. General properties of the radiation reflected from the sides of an isolated cloud are discussed. As a proof of concept, the paper shows a few examples of radiation reflected from cloud fields generated by a simple stochastic cloud model with the prescribed vertically resolved microphysics. To retrieve the information about droplet sizes, we propose to use the probability density function of the droplet size distribution and its first two moments instead of the assumption about fixed values of the droplet effective radius. The retrieval algorithm is based on the Bayesian theorem that combines prior information about cloud structure and microphysics with radiative transfer calculations.