44 research outputs found
Production of nanoporous sorbents by partial steam-air conversion of charcoal
An effective sorbent is activated carbon having a developed nanoporous structure with an average pore diameter about 2-4 nm. Perspective method of activated carbon production is the partial steam conversion of the coal bed in boiler furnaces of power plants. The additional thermal energy is produced by burning the syngas. The aim of this work is to study the co-production of activated carbon and syngas by partial steam-air conversion of charcoal. Due to the presence of oxygen in the flow, intensification of conversion occurs. In the laboratory bed reactor, the mass loss curves and the syngas composition were obtained at temperatures of 800Β°C and 900Β°C. Two zones with different reaction mechanisms were identified on the height of the bed. The reactions between carbon and steam shift toward hydrogen formation in the oxygen zone. The dependence of the porous structure of the activated carbon on the conversion degree of the raw material is obtained. The maximum of micropores is formed at a conversion degree of 0.5. The material and energy balance of the partial conversion in the laboratory reactor was estimated. Β© 2018 Institute of Physics Publishing. All rights reserved.Russian Foundation for Basic Research (RFBR
Thermal analysis of wood fuel pyrolysis process
The paper presents the results of studies of conversion process on the laboratory pyrolysis reactor and the results are compared with data, obtained in model experiments by thermogravimetric analysis (TGA). The heating rates were compared in the pyrolysis reactor and in the laboratory furnace of TGA in the pyrolysis process of wood biomass conversion. The laboratory pyrolysis reactor, as a part of the multistage gasification facility of low-grade solid fuel, was launched in several modes. Three experimental modes of the device operation with different screw speeds and fuel flow rates through the reaction shaft were tested. The temperature profile of fuel and wall along the length of the pyrolysis reactor was shown. The temperature up to 600 Β°C was recorded in a mode with a low fuel flow rate, and in the end of the reaction zone the fuel temperature was close to that of the wall. The kinetic coefficients and conversion rates for the wood biomass pyrolysis were calculated from the obtained equation. Therefore, the calculated data of the conversion rate and the pyrolysis parameters, based on the TGA data, can be used to further develop the pyrolysis reactor and evaluate the parameters of its operation. Β© 2018 Institute of Physics Publishing. All rights reserved.The research was performed at Melentiev Energy Systems Institute SB RAS under the support of Russian Science Foundation (Grant β 16-19-10227) and by using the Unique Scientific Plant βHighβtemperature circuitβ.Russian Foundation for Basic Research (RFBR
Metabolic disorders and the risk of COVID-19
In the present review the analysis of the world literature devoted to the study of metabolic disorders in the body and the risk of COVID-19 disease. It is known that metabolic syndrome is an independent risk factor for the severe course of new coronavirus infection. This review summarizes data on the mechanisms of metabolic dysfunction in a new coronavirus infection, analyzes the results of studies that investigated the issues of associations between the course of COVID-19 and various metabolic disorders, such as hyperglycemia and diabetes mellitus, dyslipidemia, obesity, non-alcoholic fatty liver disease, their severity, potential targets of therapy, predictors of the development of a severe course of new coronavirus infection are considered. These metabolic disorders increase the impairment of the immune system and make patients more susceptible to the development of infectious diseases, in particular, to infection with a new coronavirus infection. Taking into account the obtained data, it becomes obvious the need to identify and monitor patients with pre-existing metabolic diseases, as well as their development during and after COVID-19. The information on the topic from publications based on PubMed, PubMed Central, Scopus, Google Scholar, Medscape, UpYoDate, eLIBRARY.RU data were used
MODELING OF COMBINED HEAT AND POWER PLANT BASED ON A MULTI-STAGE GASIFIER AND INTERNAL COMBUSTION ENGINES OF VARIOUS POWER OUTPUTS
The kinetics parametrs of solid fuel pyrolisys
The paper presents the characteristics of solid fuels such as peat, brown coal, Kuznetsk coal and anthracite, Physical-mathematical models of the fuel conversion process are described. The kinetic parameters of the conversion of the yield of volatile 4 types of fuels with nonisothermal heating in air are calculated from two physico-mathematical modelsΠ ΡΠ°Π±ΠΎΡΠ΅ ΠΏΡΠΈΠ²Π΅Π΄Π΅Π½Ρ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠΈ ΡΠ²Π΅ΡΠ΄ΡΡ
ΡΠΎΠΏΠ»ΠΈΠ² ΡΠ°ΠΊΠΈΡ
ΠΊΠ°ΠΊ: ΡΠΎΡΡ, Π±ΡΡΡΠΉ ΡΠ³ΠΎΠ»Ρ, ΠΊΡΠ·Π½Π΅ΡΠΊΠΈΠΉ ΡΠ³ΠΎΠ»Ρ ΠΈ Π°Π½ΡΡΠ°ΡΠΈΡ, ΠΠΏΠΈΡΠ°Π½Ρ ΡΠΈΠ·ΠΈΠΊΠΎ-ΠΌΠ°ΡΠ΅ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΌΠΎΠ΄Π΅Π»ΠΈ ΠΏΡΠΎΡΠ΅ΡΡΠ° ΠΊΠΎΠ½Π²Π΅ΡΡΠΈΠΈ ΡΠΎΠΏΠ»ΠΈΠ²Π°. Π Π°ΡΡΡΠΈΡΠ°Π½Ρ ΠΊΠΈΠ½Π΅ΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΡ ΠΊΠΎΠ½Π²Π΅ΡΡΠΈΠΈ Π²ΡΡ
ΠΎΠ΄Π° Π»Π΅ΡΡΡΠΈΡ
4 Π²ΠΈΠ΄ΠΎΠ² ΡΠΎΠΏΠ»ΠΈΠ² ΠΏΡΠΈ Π½Π΅ΠΈΠ·ΠΎΡΠ΅ΡΠΌΠΈΡΠ΅ΡΠΊΠΎΠΌ ΡΠ°Π·ΠΎΠ³ΡΠ΅Π²Π΅ Π² Π²ΠΎΠ·Π΄ΡΡΠ½ΠΎΠΉ ΡΡΠ΅Π΄Π΅ ΠΏΠΎ Π΄Π²ΡΠΌ ΡΠΈΠ·ΠΈΠΊΠΎ-ΠΌΠ°ΡΠ΅ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠΌ ΠΌΠΎΠ΄Π΅Π»ΡΠΌ
Associations of changes in lipid metabolism parameters and the severity of COVID-19 infection in Novosibirsk residents
Aim. To study the associations of changes in lipid metabolism parameters and the severity of a coronavirus disease 2019 (COVID-19).Material and methods. This cross-sectional study included 270 patients aged 26-84 years (mean age, 53,09Β±13,22 years) who had COVID-19 within prior two months, which were divided into 3 groups: mild (1, n=128), moderate (2, n=128) and severe (3, n=14) COVID-19. Patients were assessed for body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), total cholesterol, triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C). In addition, atherogenic index of plasma (AIP) was calculated. Statistical processing was performed using the SPSS software package (version 13.0).Results. Patients with severe COVID-19 had significantly higher levels of TG and AIP compared with patients with moderate and mild course. BMI and WC were significantly higher in patients in groups 2 and 3 compared with patients in group 1. In women, BMI and AIP levels were significantly higher in the severe COVID-19 group compared to groups 1 and 2. HDL-C levels were lower in patients with severe COVID-19 compared to those with moderate disease. WHR was higher among men in group 3 compared with group 1.Conclusion. Patients with severe COVID-19 have higher BMI, WC, AIP, TG levels, and lower HD-C levels. The relative odds for severe COVID-19 are associated with increased WC, AIP, TG, and lower HDL-C
Magnetic and magnetoimpedance properties of rapidly quenched ribbons of modified alloys based on FINEMET
Amorphous and nanocrystalline materials are attractive systems for basic research and technological applications. In a view of the energy economy and global warming concepts there is a request to search for soft magnetic materials for sensor applications, which do not request additional heat treatments and can be produced in most simple technological scheme. In this work the structure, static magnetic properties and magnetoimpedance (MI) were studied for FINEMET-type materials both with classic composition and for compositions with 10 % of iron substitution by Co, Ni, or Mn in initial state, i.e. without any additional heat treatmnet. The best MI responses were obtained for Mn-doped rapidly quenched ribbons. Β© Published under licence by IOP Publishing Ltd.Ministry of Education and Science of the Russian Federation,Β Minobrnauka: 3.6121.2017/8.9The results were obtained under financial support of the state task of the Ministry of Education and Science of Russia 3.6121.2017/8.9. We thank D. Schishkin for special support
Non-alcoholic fatty liver disease and metabolic liver dysfunction in the new coronavirus infection COVID-19
Our study aimed to explore associated non-alcoholic fatty liver disease (NAFLD) and metabolic liver dysfunction influence on the severity of the new coronavirus infection COVID-19. Material and methods. The study design was a cross-sectional study. The research included 215 patients (39.50 % of men) aged 26β60 years who had undergone a new coronavirus infection COVID-19 at least two months ago. Participants were divided into three groups by severity of infection: mild (n = 99), moderate and severe (n = 116) by anamnesis. Hepatic steatosis index (HIS), body mass index (BMI), waist circumference, alanine aminotransferase and gamma-glutamyl transpeptidase activity, glucose and triglyceride content, systolic and diastolic pressure were calculated and abdominal ultrasound examination was done. Results. In the group with moderate and severe course of COVID-19, the proportion of patients diagnosed with NAFLDaccording to the HSI index was significantly higher compared to patients with mild coronavirus infection. Patients with mild COVID-19, who were diagnosed with NAFLD, had higher alanine aminotransferase and gamma-glutamyl transpeptidase activity, glucose and triglyceride content, BMI, systolic and diastolic pressure, waist circumference compared to patients without NAFLD. Similar differences persisted for patients with moderate and severe course. With the step-by-step exclusion of cardiometabolic parameters from the logistic regression model, the triglyceride content and BMI retained association with steatohepatosis according to ultrasound data, regardless of severity. When creating a similar model for the HSI index, significant correlation was shown for alanine aminotransferase activity in patients with mild COVID-19, for alanine aminotransferase activity and BMI β in patients with moderate and severe COVID-19. Conclusions. Patients with NAFLD have a more severe course of COVID-19. In addition, associations of the severity of COVID-19 with a combination of NAFLD and other cardiometabolic changes in the body, such as arterial hypertension, obesity, dyslipidemia, were revealed
Changes in glomerular filtration rate in young adults: population data
Aim of the study was to investigate glomerular filtration rate in population of 25β45 years old young people of Novosibirsk city. Material and methods. A survey of Novosibirsk typical districtβs population has been carried out by the Institute of Internal and Preventive Medicine since 2013 to 2016. 1074 people (467 males and 607 females of 25β45 years old) have been included into the survey. The levels of glomerular filtration rate (GFR) were chosen according to KDIGO (2012) recommendation, such as: GFR more than 90 ml/min/1.73 cm2 β high or optimal, 60β89 ml/min/1.73 cm2 β slightly reduced, 45β59 ml/min/1.73 cm2 β moderately reduced, 30β44 ml/min/1.73 cm2 β vastly reduced, 1529 ml/min/1.73 cm2 β highly reduced, lower than 15 ml/min/1.73 cm2 β terminal renal failure. Results and discussion. Average GFR(CKD-EPI) level in all age groups was 99,9 ml/min/1.73 cm2 . Average GFR(CKD-EPI) was 104.41 ml/min/1.73 cm2 in 25β34 age group. Male average GFR(CKD-EPI) levels in appropriate age groups were reliably higher comparing to female levels. Both male and female analyzed indicators turned out to be reliably lower in older group than in the younger one. 95.1 % of male participants at the age from 25 to 34 years old had GFR β₯ 90 ml/min/1.73 cm2 , while female indicator was 76.9 %. The indicators in the age group from 35β45 years old were: for males β 86.4 %, for females β 58.3 %. Both male and female groups at the age from 35 to 45 contained people with GFR < 60.ml/min/1.73 cm2 (2 men β 0,8 %; 1 woman β 0.4 %). While GFR calculating according to MDRD and CKD-EPI formulas two dissimilar results were revealed. The advantages of CKD-EPI formulas calculating for higher GFR indicators have been evidenced