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Previously we have developed the PLGA nanoparticles loaded with doxorubicin (PLGA-DOX NP) that demonstrated a high anti-tumor effect against the rat glioblastoma in the preclinical studies and is now being evaluated in the clinical phase II study. This formulation was obtained by a generally accepted homogenization ? solvent evaporation technique followed by freeze-drying. The purpose of the present study was to explore the feasibility to simplify the process of the nanoparticle preparation by replacing a freeze d...

The study was conducted to study the effect of cerium dioxide nanoparticles on the survival of zebrafishand the microbiome of their intestines. With respect to the intestinal microbiome in the control group, it was registered that the majority of the identified bacteria belonged to Proteobacteria. A peculiar action of CeO2nanoparticleson the intestinal microbiota was an increase in the number of Firmicutes, in particular, Bacilli class bacteria, and a decrease of Proteobacteria phylum, it was manifested in the flu...

The paper describes a new design of a directional coupler with four plug-in quarter-wave loops. Four loops increase the operating frequency band several times, but the area of the device also grows by two quarter-wave segments in length. It is not always possible to use such a large device area, for this reason, techniques are used to reduce the size of the device with minimal loss in its characteristics. Using miniaturization, which is the use of compact structures, it was possible to reduce the size of a quarter...

Acrylic derivative-based superabsorbents are widely used currently in agriculture as the soil conditioners, plant growth regulators, etc. Their usage has a positive effect on the growth and survival of the plants cultivated in the arid regions. However, the effects of hydrophilic acrylic polymers on the soil microbiocenosis still remain unknown. The influence of the moisture-absorbing acrylic acid-based hydrogels with different concentration of bentonite filler was studied on the soil microbiota. N,N-methylenebisa...

In this paper we describe the synthesis and characterization of nano-sized TiO2 particles supported on sepiolite fibres with sepiolite to TiO2 weight ratios of 30:70, using sepiolite from Korinthos, Greece. Sepiolite - TiO2 nanocomposites were prepared by deposition of anatase form of TiO2 on the sepiolite surfaces using a sol?gel method with titanium isopropoxide as a precursor under hydrothermal treatment at 180 °C. The characterization includes phase composition, particle morphology, while the physical properti...

Nowadays, modern technical solutions in various spheres of human activity from the opto-electronics up to nanobiotechnology are increasingly dependent on the level of technology. Applied research on nanomaterials plays a key role in the development of nanotechnologies. The nanostructured silicon is one of the materials attracting the special attention of researchers in various applied areas. A new and widely discussed application of nanostructured silicon is a possibility of their usage in the process of efficient...

Based on the exergetic analysis the paper analyses the conduct of a simple Linde cryogenic refrigeration cycle looking for its weaknesses and trying to find ways for operating or structural improvements. The exergetic analysis reveals that a major exergy destruction is due to heat transfer across a finite temperature difference in the recuperative heat exchanger. The optimization procedure points out that this exergy destruction reaches a minimum if the temperature difference between the high (hot) and low pressur...

Directional couplers are widely used in microstrip technology, but their dimensions are tied to the operating frequency. Since the smaller the frequency, the longer the longitudinal length of the quarter-wave segments and the greater the overall dimensions of the coupler. For this reason, use miniaturization, which allows to reduce the area occupied by the device on the substrate, with negligible loss in performance. In addition, there is an economy of the material used in the manufacture of the microstrip device....

The goal of this work is to study the processes of producing carbon aerogels, silica-carbon aerogels and CNT-silica aerogels and search for new areas of their applications. To achieve this goal, aerogels using the sol-gel method and the supercritical drying process were synthesized. The analysis of the obtained aerogels was carried out using the methods of nitrogen porosimetry and scanning electron microscopy. In addition, a software that uses cellular automaton models to generate virtual structures of the studied...

It was found that the mechanically activated highly dispersed component based on saponite-containing waste of the diamond industry allows us to improve the physicomechanical characteristics of fine-grained concrete due to the formation of hydrosilicates of additional generation. According to the working hypothesis, the resulting new formations are submicrocrystals of the tobermorite group. The objective of this study was to identify the products of the hydration of clinker minerals with a component on the basis of...

Microstrip directional couplers are made on microwave substrates, which consist of various dielectric materials. With a decrease in the operating frequency, the dimensions of the coupler increase, and more material is required for their manufacture. To reduce the consumable material, you can use different approaches to miniaturize the couplers, this will reduce the size of the device while maintaining its characteristics. So this article presents the results of research to reduce the occupied area of a flat crosso...

To date, the study of the action of ionizing radiation on the structure and properties of polymers, as well as on their basis of composite materials remains an urgent task. Studies of the impact of different types of radiation on polymeric materials, primarily due to the practical interest due to the need to solve the problems of improving the reliability of devices and devices operating in the field of radiation, as well as the prospects of radiation technologies to provide targeted modification of the properties...

The features of the influence of thermal fields on the deformation of polyimide films are investigated. It has been established that the effect of static load up to 50% Fmax leads to the structuring of polyimide films, and starting with F ? 70% Fmax, amplifications of destruction processes in them are caused. Heating to 433 K and the application of a load leads to the structuring of macromolecules of polyimide in the direction of the impact of the load, leading to linear growths of relative elongation and an incre...

In the vegetable growing field, the germination is an important indicator in the appreciation of seeds quality. The process takes place over a variable period of time being influenced by a number of factors such as species, environmental conditions and the treatment applied to the seeds. We used citrate - stabilized gold nanoparticles to prevent the occurrence of fungi and to stimulate the germination process of carrot seeds. The gold nanoparticles were synthesized by mixing and heating aqueous solutions of chloro...

Aerogels are promising materials for use in various industries such as chemical, pharmaceutical, medicine and food industry. These highly porous materials have unique properties, including high adsorption capacity, which makes it possible to successfully impregnate various substances into aerogels: active pharmaceutical ingredients (APIs with low solubility and bioavailability), various oils (for example, high volatile), additives for the food industry (vitamins and aromas) and many others. The aim of present inve...

In materials science, composites (nanocomposites) are materials consisting of a combination of two or more micro (nano-) and / or macrocomponents, which are different in shape, chemical composition and do not have significant mutual solubility. A distinctive feature of composites that determine their importance is that two or more noticeably different components when combined form a system that has significantly improved properties compared to the properties of its individual components. It is known that for most ...

The thickness of the blood-brain barrier (BBB) basement membrane (BM) in vivo is in the range of 20 - 200 nm. Most widely used commercially available microporous polycarbonate (PC), polyethylene terephthalate (PET) or polytetrafluoroethylene (PTFE) membranes are 10 to 50 ?m thick. This is a substantial obstacle for communication of cells growing on both sides of membrane, like astrocytes, pericytes and endothelial cells within in vitro BBB model. For the last several years the active development of ultrathin micro...

A passive method is proposed in this research for minimization of the temperature drift of a strapdown inertial navigation system with fiber optic gyroscopes and accelerometers by means of reduction of the temperature differences between the structural components of individual gyroscopes as well as between gyroscopes and accelerometers. For this purpose, theoretically possible use of nanostructured composite materials based on carbon nanotubes and characterized by increased thermal conductivity in individual struc...

This research deals with the aspects of use of the heat balance method for calculation of three-dimensional non-uniform non-steady temperature fields of complex optoelectronic systems through the example of a measuring unit based on fiber optic gyroscopes and microelectromechanical accelerometers. The main principles of and approaches to development of a mathematical model of the temperature field of the unit under consideration on the basis of the heat balance method have been set forth. The adequacy of the devel...