Modelling of the thermal state and the melting loss of a graphite electrode in the conditions of the evaporative cooling in the arc furnace

The cost of the graphite electrodes amounts greater proportion in the final value of the finished product. This calls for finding opportunities to reduce the maintenance costs of AC and DC furnaces used in foundries. The aim of the study is the creation of a mathematical model and the analysis of the efficiency of the evaporative cooling method in reducing the amount of the graphite electrodes used in small capacity arc furnaces. The mathematical model and the computer program allow determining the thermal state of the electrode and the melting loss of the graphite, the model is developed for a primarily cylindrical electrode and takes into account: the current passing through an electrode, the time of the electrode being in the electrified furnace, and the parameters of the water evaporative cooling. The paper presents the received data about the melting loss of the graphite per ton of steel against the water consumption during the evaporative cooling. The graphite consumption in the arc furnaces of 10-12 tons' capacity is reduced by 40 %. The recommended water consumption for the evaporative cooling of electrodes for all types of foundry furnaces is 0.1-0.2 m3/h. © Published under licence by IOP Publishing Ltd

Animal image in easel sculpture of the 20th century

Автор анализирует русскую анималистическую скульптуру ХХ в., прослеживает периодизацию ее развития, отмечает значимость этого вида пластики в реалистической трактовке образа животного.В статье анализируется станковая анималистическая скульптура XX в., прослеживается периодизация ее развития, отмечаются значимость и преимущества этого вида пластики в реалистической трактовке образа животного

Regional Arterial Stiffness in Patients with Inflammatory Bowel Disease

Aim.  To study muscular (brachial and radial arteries) and elastic (aorta) regional arterial stiffness in IBD patients in comparison with those without IBD, as well as to establish the relationship between arterial stiffness and the characteristics of the IBD course (the duration of illness, severity of attack, activity of systemic inflammation). Materials and methods. The study included 21 IBD patients and 30 patients in the comparison group. The values of regional aortic and muscular arterial stiffness were measured by applanation tonometry. The carotid–femoral pulse wave velocity (cfPWV) and the carotid-radial pulse wave velocity (crPWV) were determined. The laboratory research plan included the analysis of complete blood count, biochemical parameters, fibrinogen and a high sensitivity  C-reactive protein (hsCRP).Results. crPWV, similar to cfPWV, was not significantly different between the groups. At the same time, the proportion of individuals with an increase in the cfPWV of more than 10 m/s was higher in the group of IBD patients. However, these differences did not reach the level of statistical significance. According to the results of the correlation analysis, the increase in cfPWV was associated with an increase in patient age (r = 0.564; p = 0.01), the duration of IBD history (r = 0.628; p = 0.003), fasting plasma glucose (r = 0.367; p = 0.034) and GFR decrease (r = -0.482; p = 0.031). The crPWV also directly correlated with the IBD duration (r = 0.630; p = 0.003). According to the results of the regression analysis, an increase in the IBD duration by 1 year is associated with an increase in cfPWV by 0.205 m/s, i.e. the increase in the IBD duration by 5 years is associated with an increase in the cfPWV of approximately 1 m/s.Conclusion. In IBD patients, the duration of the disease directly correlated with an increase in cfPWV and crPWV. The increase in the IBD duration by 1 year was associated with an increase in cfPWV by 0.205 m/s. The muscular and elastic regional arterial stiffness was not statistically significantly different between IBD patients and the comparison group

Ultrasound examination of achilles tendons in patients with familial hypercholesterolemia

Aim. To assess the morphometric characteristics of Achilles tendons in patients with familial hypercholesterolemia (FH) and to identify factors associated with an increase in their size.Материал и  методы. Totally, 100 patients included, with severe primary hyperlipidemia, defined as an increase in total cholesterol ≥7,5 mM/L and/or lowdensity lipoprotein cholesterol ≥4,9 mM/L. All patients underwent duplex scanning of carotid arteries. Ultrasound examination of the Achilles tendons was carried out on an expert class ultrasound equipment Samsung Medison EKO 7 (Japan) with a linear sensor, frequency of 7-16 MHz. Thickness of the Achilles tendon (anteriorposterior dimension (APD)) was measured during scanning in the longitudinal section, width (transverse dimension (TD)) — scanning in the cross section. The measurements were made 2 cm proximal to the calcaneus.Results. Among the participants, 32 (32,0%) had definite/probable diagnosis of FH. In patients with definite/probable FH the mean values   of APD were significantly higher in comparison with patients scored 5 or less points (DLCN) — 5,50 (4,70-6,10) mm vs. 5,00 (4,50-5,40), respectively (p=0,04). TD of Achilles tendons among this category of patients was also statistically significantly higher in comparison with the rest of patients — 14,0 (12,9-15,4) mm and 13,2 (12,2-14,2) mm, respectively (p=0,04). In correlation analysis, the relationship between the growth of patients and the APD of the Achilles tendons (r=0,34, p=0,001), the TD of the Achilles tendon (r=0,28, p=0,009), CIMT and TD of the Achilles tendons (r=0,21, p=0,05), amount of carotid plaques and TD of the Achilles tendon (r=0,26, p=0,01), total percentage of stenosis of the carotid arteries and the TD of the Achilles tendons (r=0,27, p=0,01), maximum percentage of stenosis of the carotid arteries and the TD of the Achilles tendons (r=0,28, p=0,007). According to regression analysis, factors associated with an increase in thickness of the Achilles tendons for more than 75 percentiles were male sex, diabetes mellitus, height, myocardial infarction in relatives, total percentage of stenosis of the carotid arteries and high-density lipoproteide cholesterol.Conclusion. In patients with definite/probable FH, mean values of width and thickness of the Achilles tendons were significantly higher in comparison with the rest of the patients. According to regression analysis, the factors associated with the increase in thickness of the Achilles tendons fro more than 75 percentiles were male sex, diabetes mellitus, height, myocardial infarction in relatives, total percentage of stenosis of the carotid arteries and HDL high-density lipoproteide cholesterol