Effect of Molecular Weight on the Properties of Polyethyleneglycols Doped with Multiwalled Carbon Nanotubes

The aim of this study is to analyze the changes in the structure, thermal properties and electrophysical behavior of polyethylene glycol doped with multiwalled carbon nanotubes. The differential scanning calorimetry and electrical conductivity methods were used to study influence of doping multiwalled carbon NTs on the properties of polyethylene glycol of different molecular weights, Mw (PEG-400, PEG-1000, PEG- 10000). Dependencies of the polymers degree of crystallinity and temperature behavior of conductivity on the concentration of NTs were researched. The obtained data indicates a strong influence of the molecular weight of PEG on the spatial distribution of NTs and electrical conductivity of researched systems

Synthesis Submicro- and Nanoscale Spherical Silica Particles with 3-aminopropyl Groups in the Surface Layer

Stöber’s method and two-component systems (considering alkoxysilanes) were used to develop tech-niques for the synthesis of spherical silica particles with ≡Si(CH2)3NH2 groups in the surface layer. The in-fluence of synthesis conditions on the size of synthesized spherical particles and concentration of functional groups were studied. DRIFT, SEM and acid–base titration were used to identify the composition of the sur-face layers and morphology of the obtained silica particles. There was analyzed the influence of the order entry components, the stirring time, the drying mode, the ratio of reacting of alkoxysilanes, the tempera-ture, and the amount of water and solvent on the morphology, the size of synthesized spherical particles and the content of functional groups in the silica spheres. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3525

The Impact of the Nanostructure of the Functional Polysiloxane Layer in Planar Ceramic Membranes on Their Sorption Properties

The paper describes the functionalization of planar ceramic membranes (Al2O3) with the active layer containing 3-mercaptopropyl complexing groups. The sol-gel method was used for that. There was analyzed the influence of the ratio of alkoxysilanes and the dilution of the original sol on the nanostructure of the produced surface layer. The work is aimed to develop the techniques for ceramic membranes functionalization by complexing groups, therefore, these membranes can be used for the removal of heavy metal ions from aqueous media in the process of filtration. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3534

The Role and Influence of “Clip Thinking” on the Educational Process in Medical Education

Information technology has strengthened the role of information, leading to the fact that modern society has reached a new stage of development – information. A fundamentally new way of communication and information broadcasting called the “screen culture” is emerging. The information society influences the society of people, their training and management processes. This influence is transforming our thinking, and therefore such concepts as “human-screen”, “clip thinking” and “clip consciousness” appear more often in the academic literature

Surface ZnSe:Ca layers with hole conductivity

The authors investigate the effect of treating n-ZnSe substrates with boiling aqueous Ca(NO₃)₂ suspension on their electrical and luminescent properties. Base substrates were cut from bulk pure zinc selenide crystals grown from a stoichiometric melt by the Bridgman method. It was found that the Ca-doping of the substrates causes an almost complete “quenching” of the low-energy orange emission band with a maximum near hωmax ≈ 1,95 eV and a significant increase in the efficiency of the edge blue luminescence band.Исследовано влияние обработки подложек n-ZnSe в кипящей водной суспензии соли Ca(NO₃)₂ на их элек-трические и люминесцентные свойства.Досліджено вплив обробки підкладинок n-ZnSe в киплячій водній суспензії солі Ca(NO₃)₂ на їхні електричні та люмінесцентні властивості

FEATURES OF FATAL INJURIES WHEN SHOOTING FROM CONVERTED AND REACTIVATED WEAPONS (TWO CASES FROM EXPERT PRACTICE)

Relevance. Gunshot injuries from converted and re-activated (remanufactured) weapons are increasingly common in expert practice. This is due to the free circulation of such weapons, which are not controlled by authorized bodies, no documents or registration are required for their acquisition, and their transfer to a combat state is a technologically simple and fast process. Objective: analysis of the nature and characteristics of injuries caused by shots from converted and reactivated weapons, based on data obtained in forensic medical expert practice in the study of corpses of victims with gunshot wounds to the head, as well as on the results of forensic ballistic examinations of firearms and ammunition for them. Materials and methods. Cases of forensic medical examination of gunshot wounds to the head when fired from converted and reactivated (recovered) hand-held firearms, resulting in the death of the victims. Results. The study found that the use of signal weapons (pistol "Stalker-M906" converted for firing pistol cartridges of 9 mm RA caliber) and recovered neutralized weapons (mass-dimensional model of a 7.62 mm Nagant revolver equipped with non-standard ammunition) when fired at point-blank and at close range led to fatal penetrating gunshot wounds, accompanied by perforated fractures of the skull bones, destruction of the brain substance and intracranial hemorrhages. Conclusions. The analyzed cases of gunshot wounds when fired from converted and reactivated weapons indicate the potential danger of causing fatal injuries to a person. Consequently, an important issue is to strengthen control over the circulation, use and storage of signal and neutralized weapons

Undulative induction electron accelerator for the waste and natural water purification systems

The project analysis of Undulative Induction Accelerator (EH-accelerator) for the waste and natural water purification systems is accomplished. It is shown that the use of the four-channel design of induction block and the standard set of auxiliary equipment (developed earlier for the Linear Induction Accelerators - LINACs) allow to construct commercially promising purification systems. A quality analysis of the accelerator is done and the optimal parameters are chosen taking into account the specific sphere of its usage

Пам’яті Лідії Григорівни Оляніцької

The paper is dedicated to memory of Lidia Grygorivna Olyanitska

Anti-blastocystis activity of hop extracts in vitro.

Blastocystis sp. are the most common, unicellular, anaerobic parasites of the intestinal tract of many animal and human species that can cause various digestive diseases. Metronidazole has long been used as a first-line treatment for blastocystosis, but recent clinical and in vitro studies have demonstrated its low efficacy against Blastocystis sp. The aim of this study was to determine the in vitro sensitivity of Blastocystis sp. clinical isolates to carbonic acid hop extracts and alcohol hop extracts in comparison with metronidazole. Five cultures of Blastocystis sp. were isolated from faecal samples from patients with irritable bowel syndrome with predominant diarrhoea (IBS-D, Rome IV). The parasites were identified by microscopy of faecal smears permanently stained with trichrome, Wheatley’s modification and Heidenhain’s iron-haematoxylin. Blastocystis sp. was cultivated at 37°C under anaerobic conditions on RPMI-1640 with antibiotics and horse serum, taking into account their growth characteristics. To detect the antiblastocystic activity hop extracts and metronidazole were tested in the range from 1000 μg/ml to 1 μg/ml.The presence and number of viable Blastocystis sp. cells were determined after 24, 48, 72 and 96 hours. Blastocystis sp. cells were counted in a hemocytometer using the trypan blue dye exclusion test. All experiments were performed in triplicate. According to the results of in vitro sensitivity of 5 clinical isolates of Blastocystis sp. to the action of carbonic acid hop extract, alcohoicl hop extract and metronidazole, a direct positive pattern in the dose-response and contact time-response effects was established. Alcoholic hop extract showed the highest level of antiblastocystic activity with indicators (for 72- hour parasite cultures) of the minimum inhibitory concentration (which inhibits the parasite cultures growth by 50%) (2.8±0,8) μg/ml and the minimum lethal concentration (which destroys parasite cells by 100%) – 8 μg/ml, being 2.4 and 4.5 times lower than the minimum inhibitory concentration and 8 and 62.5 times lower, than the minimum lethal concentration for hop extract and metronidazole, respectively (p<0.05). It has been shown that alcoholic hop extract (≥16 μg/ml) causes gradual morphological changes in Blastocystis sp. cells, leading to their complete destruction.In contrast to metronidazole, subinhibitory concentrations of hop extract (<2 μg/ml) do not stimulate the proliferation of Blastocystis sp. cells in vitro

Tin doping effect on crystallization of amorphous silicon obtained by vapor deposition in vacuum

The influence of tin impurity on amorphous silicon crystallization was investigated using the methods of Raman scattering, Auger spectroscopy at ion etching, scanning electron microscopy and X-ray fluorescence microanalysis in thin films of Si:Sn alloy manufactured by thermal evaporation. Formation of Si crystals of the 2 to 4- nm size has been found in the amorphous matrix alloy formed at the temperature 300 C. Total volume of nanocrystals correlates with the content of tin and can comprise as much as 80% of the film. The effect of tin-induced crystallization of amorphous silicon occurred only if there are clusters of metallic tin in the amorphous matrix. The mechanism of tin-induced crystallization of silicon that has been proposed takes into account the processes in eutectic layer at the interface metal tin – amorphous silicon