14 research outputs found
The features of application of eutectic melts based on indium and gallium
In a brief review, the main trends in the use at the present time of eutectic melts based on indium and gallium (EGaIn) are considered. Examples of the use of EGaIn in transistors, capacitors, electrodes, and probe systems (including those in four-probe techniques) are given. The main properties of EGaIn and the spreading of a drop of EGaIn melts are considered, and a detailed scheme of the point-contact four-probe method is given. The main issues discussed in the application of EGaIn in the field of obtaining liquid electrodes, including the formation of gallium oxides, the possibility is revealed of the influence of the spatial environment on the EGaIn droplet and manipulation of microdroplets,. It has been established that among the works of 2022-2023, a large segment is occupied by publications in the field of flexible electronics, intelligent robots, as well as wearable devices (for example, the creation of a metatissue with an antibacterial effect and the ability to be heated with a low energy consumption) and biomedical applications (the development of smart gloves for manipulating gestures, measuring the heart rate of insects)
Improving the sensor characteristics of binary and ternary oxide nanosystems
Currently, adsorption gas sensors are of great interest for environmental monitoring. The approaches to improving their properties include synthesis of nanostructured materials of various shapes and modification of the metal oxide chemical composition. The aim of this work is to develop ways to improve the sensor properties of zinc oxide nanowires by changing the surface structure during processing in solutions of tin and iron compounds, as well as adding special precursors during their synthesis. The layers consisting of zinc oxide nanowires were produced by hydrothermal method. Ternary Zn-Sn-O and Zn-Fe-O nanosystems were synthesized as a result of processing of zinc oxide nanowires in solutions containing potassium stannate and iron sulfate, respectively. ZnO nanowires were also synthesized in a solution containing sodium bromide in addition to the general precursors. The surface chemical composition was analyzed using X-ray photoelectron spectroscopy. Sensor properties were investigated by detecting acetone, isopropanol and methanol vapors. It was shown that the sensor response of the produced samples exceeds the response of the initial zinc oxide nanowires. The samples of Zn-Sn-O ternary oxide system have the best response. The improvement of the sensor response may be associated with an increase in the content of adsorbed oxygen ions on the surface of the samples, the presence of metal cations with different properties as well as the formation of heterostructures
Study on the microporous structure parameters of BEA type zeolites
The paper considers a series of zeolite materials used as catalysts. Since the formation of mesoporosity in a microporous matrix is one of the methods for increasing the efficiency of zeolite materials in catalysis, it is necessary to control their porous structure parameters. The effect of post-synthetic treatment with acid and alkali solutions on the specific surface area of zeolites of the BEA type has been studied. The method of low-temperature (at 77 K) adsorption of nitrogen vapors was used to determine the external specific surface area (excluding micropores) and the volume of micropores in the samples on a Sorbi device. It has been shown that modification of BEA-type zeolite with concentrated mineral acids leads to both a decrease in the volume of micropores and a decrease in the specific surface area. At the same time, it was established by the X-ray phase analysis that the treatment with concentrated acids does not lead to destruction of the crystal structure of zeolites. In the case of treatment with alkali solutions, the specific surface area of the samples increases and the volume of micropores sharply decreases
Development of a manual extruder for liposome homogenization
Medications using liposomes are of great interest in pharmaceuticals. They increase the therapeutic index of the drug by enclosing the medicinal substance inside a biocompatible lipid envelope, which releases the solution only in the required area. Such drugs have already shown their effectiveness in the treatment of diseases related to oncology, dermatology, neurology, surgery, etc. To use liposomes for these purposes, it is necessary that their size be in the range from 50 to 200 nm. There are several ways to create vesicles of this size, but mostly they use either ultrasound exposure to a liposome solution or extrusion. The extrusion method is a method that allows to obtain the most homogeneous solution from liposomal particles. For extrusion, a special device – an extruder is required. It is a system that passes a liposomal solution under pressure through a filter with a certain pore size. In this paper, the process of liposome extrusion, types of liposomal extruders are considered and their pros and cons are evaluated, a model of a manual extruder capable of homogenizing up to 20 ml of solution was also developed. Different materials were considered and used for the construction of this device. The inspection of the extruder showed its operability and showed the advantages of using extrusion compared to the ultrasound exposure method
Fluorescence of ZnO2:SiO2 and SnO2:SiO2 Nanosized Composite Films under the Action of Human Serum Albumine
[No abstract available
Light conversion in thin films of mixtures of mesotetraphenylporphyrin and yttrium vanadate crystallites doped with erbium. I. Photovoltaic properties and structure
The optical and photovoltaic properties of two-component TPP–Yt0.95Er0.05VO4 films prepared by the spincoating method are for the first time studied. A 30% increase in the photovoltage (PV) of TPP: Yt0.95Er0.05VO4 = 3: 2 films on silicon carbide (SiC) supports as compared to TPP one-component films is observed. In contrast, for films on tin dioxide (SnO2) supports, the PV drops by 35–96% as the TPP content in the film decreases from 80 to 20%. The properties of the films are monitored by atomic force microscopy. The highest roughness of the films corresponds to a 40–60% TPP content. © 2016, Pleiades Publishing, Ltd
Fluorescence of ZnO:SiO2 and SnO2:SiO2 nanosized composite films under the action of human serum albumin
[No abstract available
Light conversion in thin films of mixtures of mesotetraphenylporphyrin and yttrium vanadate crystallites doped with erbium. I. Photovoltaic properties and structure
The optical and photovoltaic properties of two-component TPP–Yt0.95Er0.05VO4 films prepared by the spincoating method are for the first time studied. A 30% increase in the photovoltage (PV) of TPP: Yt0.95Er0.05VO4 = 3: 2 films on silicon carbide (SiC) supports as compared to TPP one-component films is observed. In contrast, for films on tin dioxide (SnO2) supports, the PV drops by 35–96% as the TPP content in the film decreases from 80 to 20%. The properties of the films are monitored by atomic force microscopy. The highest roughness of the films corresponds to a 40–60% TPP content. © 2016, Pleiades Publishing, Ltd