ABOUT THE POSSIBILITY OF CREATING A HIGH-PERFORMANCE SENSOR BASED ON BORON NITRIDE NANOTUBES

The possibility of attaching a chlorine atom to the outer surface of a single-layer borocar-bon ВС3 of a type A and B nanotube was investigated, namely, adsorption of a Cl atom was studied. Calculations were performed within the molecular cluster model using the MNDO [1] semiempiric scheme.Researches are executed with financial support of a grant of the Russian President № МК-1758.2020.8

Evaluation of the energy efficiency of functioning and increase in the operating time of hydraulic drives of sucker-rod pump units in difficult operating conditions

The necessity of improving the drives of sucker-rod pump units operated in conditions of low-yielding and complicated wells was substantiated. For complicated oil production conditions the use of hydraulic drive is promising, it allows selecting and setting rational operating regimes of downhole equipment. The results of comparative tests of traditional mechanical and hydraulic drives with pneumatic and electrodynamic balancing types are presented. The generalized indicator of assessing the efficiency of operation of prospective hydraulic drives for DCSN is suggested - the energy efficiency coefficient ke.ef, equal to the ratio of the average value of specific energy consumption for production of well fluid during operation of DCSN equipped with a balancing pumping unit to the average value of specific energy consumption for production of well fluid during operation of the tested hydraulic drive for DCSN. It was experimentally proved that the use of hydraulic drive of DCSN with pneumatic balancing is characterized by low energy efficiency of the process of production of well fluid. Proposed technical solutions aimed at improving the energy efficiency of operation and increasing the operating time of hydraulic actuators USSN in conditions of marginal and difficult wells. The methodological basis for assessing the economic efficiency of introducing promising hydraulic drives for ESPs is given

High-temperature transport properties of BaSn1−xScxO3−δ ceramic materials as promising electrolytes for protonic ceramic fuel cells

Protonic ceramic fuel cells (PCFCs) offer a convenient means for electrochemical conversion of chemical energy into electricity at intermediate temperatures with very high efficiency. Although BaCeO3- and BaZrO3-based complex oxides have been positioned as the most promising PCFC electrolytes, the design of new protonic conductors with improved properties is of paramount importance. Within the present work, we studied transport properties of scandium-doped barium stannate (Sc-doped BaSnO3). Our analysis included the fabrication of porous and dense BaSn1−xScxO3−δ ceramic materials (0 ⩽ x ⩽ 0.37), as well as a comprehensive analysis of their total, ionic, and electronic conductivities across all the experimental conditions realized under the PCFC operation: both air and hydrogen atmospheres with various water vapor partial pressures (p(H2O)), and a temperature range of 500–900 °C. This work reports on electrolyte domain boundaries of the undoped and doped BaSnO3 for the first time, revealing that pure BaSnO3 exhibits mixed ionic-electronic conduction behavior under both oxidizing and reducing conditions, while the Sc-doping results in the gradual improvement of ionic (including protonic) conductivity, extending the electrolyte domain boundaries towards reduced atmospheres. This latter property makes the heavily-doped BaSnO3 representatives attractive for PCFC applications. [Figure not available: see fulltext.] © 2022, The Author(s).We would like to give special thanks to Natalia POPOVA and Thomas BEAVITT for their performed proofreading

A Solid-State Synthesis Route Allows the Preparation of Dense Ceramic Materials Based on Alkaline Earth Stannates

Dense single-phase perovskites ceramic materials based on alkaline earth stannates BaSnO3, SrSnO3 и CaSnO3 were obtained. Scanning electron microscopy pictures were collected. A solid-state synthesis route used 0.5 wt% CuO as sintering additive is appropriate

The Effect of the Synthesis Method on the Luminescent and Dosimetric Properties of Zinc Aluminate

In this article, the thermoluminescence properties of zinc aluminate synthesized by solid-state reaction and citrate-nitrate auto-combustion routes were investigated. The dose dependence study of a low-temperature TL peak showed a sensitivity of ceramics to the obtained dose in the range of 1-80 Gy

Opisthorchis felineus infection, risks, and morbidity in rural Western Siberia, Russian Federation

The liver fluke, Opisthorchis felineus, is widely distributed throughout Europe and large parts of the Russian Federation. In Western Siberia, information about opisthorchiasis is lacking although infection may lead to severe liver and bile duct diseases. We aimed to assess the current prevalence of O. felineus infection along with associated risk factors and morbidity in rural Western Siberia.; We conducted a community-based, cross-sectional study in the rural Shegarskiy district, Tomsk Oblast, Russian Federation. All household members (≥ 7 years) present on the survey day were enrolled (n = 600). Two stool samples per person were examined for helminth eggs, using PARASEP (DiaSys Ltd, UK). The number of eggs per gram (EPG) of feces was recorded. Each study participant was interviewed to determine risk factors, using a pre-tested questionnaire. An abdominal ultrasonography examination of liver and bile ducts was performed with a mobile, high resolution ultrasound device. In total, 488 persons completed assessments (two stool samples, completed questionnaires); of those, 436 individuals had an ultrasonography (US) examination.; We observed a prevalence of O. felineus infection of 60.2%. Significant risk factors for infection were the consumption of river fish (odds ratio from adjusted analysis [aOR] 2.4, 95% CI 1.52-3.95, p<0.001), particularly stock fish (OR from multivariable analysis [mOR] 3.2, 95% CI 2.63-3.80, p<0.001), smoked fish (mOR 1.5, 95% CI 1.24-1.72, p<0.001), frozen fish (mOR 1.6, 95% CI 1.29-2.02, p<0.001), and raw fish (mOR 1.4, 95% CI 1.05-1.84, p = 0.02); and fishing activities (mOR 1.2, 95% CI 1.03-1.43, p = 0.019). Women had a higher risk of infection than men. Infection was associated positively with age and negatively with socio-economic status. The respondents' general awareness of opisthorchiasis was quite high (93.2%), but their knowledge about infection transmission and prevention was insufficient. Children aged 7-18 years old had a lower level of awareness compared to adults. The abdominal ultrasonography results demonstrated a strong association between O. felineus infection and gallbladder stones (mOR 2.8, 95% CI 1.33-6.04, p = 0.007) and periductal fibrosis of intrahepatic bile ducts (mOR 1.9, 95% CI 1.08-3.46, p = 0.026).; O. felineus infection is highly prevalent in rural regions of Western Siberia, and associated with severe hepatobiliary pathology. Identified risk factors will be used to develop a comprehensive targeted O. felineus infection control program

SYNTHESIS AND PRODUCTION OF LAYERED CERAMIC MATERIALS BASED ON BARIUM STANNATE

Single-phase Ba2–xLaxSnO4+δ samples were obtained. Their decomposition after long storage in air is observed. High levels of p and n-type electronic conductivity were determined. The materials are suitable for technical applications without contact with ambient air

ЭПИДЕМИОЛОГИЯ ОСТРЫХ КИШЕЧНЫХ ИНФЕКЦИЙ У НОВОРОЖДЕННЫХ

This article presents a retrospective analysis of the incidence of acute intestinal infections of newborns in 2006—2012 years. The analysis has revealed increased morbidity, the leading etiological role of rota-and noroviruses alongside with opportunistic pathogens, and absence of a clear seasonality. В статье представлены данные ретроспективного анализа заболеваемости острыми кишечными инфекциями новорожденных за 2006—2012 гг. Установлен рост заболеваемости, ведущая этиологическая роль ротаи норовирусов, также условно-патогенных микроорганизмов, отсутствие четкой сезонности.