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The study of the processes occurring in the temperature range of the main decomposition of the organic mass of coal (OMC) makes it possible to understand both the general patterns and the specifics of the decomposition of solid fuels. This temperature interval is used to calculate the kinetic parameters of the process, which carry important information both about the nature of the structural-chemical transformations and about the structure and direction of thermal destruction of OMC. In this article, to study the kinetics of pyrolysis of coal, the method of thermogravimetric analysis was used, in which heating of coal samples was carried out in ceramic crucibles in the temperature range of 25-900 °C at different heating rates (5-25 deg/min) in nitrogen and oxygen media. Coal from the Kenderlyk deposit was chosen as the object of study. Based on the constructed differential DTG curves (dependence of the sample mass change rate on time) at different heating rates, the kinetic parameters of pyrolysis of coal were calculated using the equations of non-isothermal formal kinetics. The effect of the rate and temperature of coal heating on the kinetic parameters of pyrolysis of coal has been studied. The main stages of OMC decomposition are revealed. It has been found that the heating rate of coal samples significantly affects the temperature and process rate corresponding to the main decomposition maxima on the differential DTG curves. The dependence between the kinetic parameters of pyrolysis of coal in the temperature range of the main decomposition of OMC on the rate and temperature of heating, as well as between the kinetic parameters at different stages of the main decomposition of coal, is analyzed. [ABSTRACT FROM AUTHOR]

The interest in this process lies in the fact that it has great value since low-octane components are used as raw materials - the n fraction. temperature – 62 °С and catalytic reforming raffinates. This raw material contains mainly pentane and hexane fractions. This raw material, as well as fractions С5 and С6 obtained from a gas fractionation unit (GFU), and a central gas fractionation unit (CGFU), are isomerized in a hydrogen environment in the presence of a catalyst. Hydrocarbons with a relatively high octane number are obtained. When isomerizing the pentane fraction, a product with a higher octane number is obtained. Isomerization of n-pentane is of interest not only for the oil refining industry, but also for the petrochemical industry, since isopentane can be converted by dehydrogenation into isoprene, a raw material for rubber. The article conducted a study on the selection of the optimal catalyst for the light gasoline fraction isomerization unit located at the Atyrau Oil Refinery. The catalytic activity of the catalyst samples was assessed in a laboratory flow-type installation. Determination of the mass fraction of С2 -С5 hydrocarbons in С5 hydrocarbon fractions (in raw materials and catalyst) was carried out by a method based on the separation of mixture components by gas-liquid chromatography. The components leaving the chromatographic column were detected using a thermal conductivity detector. The calculation of the mass fractions of components was carried out using the normalization method, taking into account correction factors. The minimum concentration of C2 -С5 hydrocarbons, determined by the method used, is 0.01-0.05% wt. [ABSTRACT FROM AUTHOR]

In the article the low-temperature pyrolysis of Kazakhstan low-grade coal with determination of physical and chemical properties of coal and products of its thermal decomposition is carried out. Elemental analysis of coal and analysis of mineral part of coal were carried out. 6 parallel experiments of the process of low-temperature pyrolysis of coal were carried out, as a result of which the yields of such products as semi-coke, tar, combustible gas were determined, and also their main characteristics (component composition, calorific value, etc.) were determined. The convergence of the results (from 6 experiments) is quite satisfactory. The heat balance of coal pyrolysis was carried out taking into account the average yields of products.

Practically and theoretically important are studies aimed at creating new methods for purifying copper electrolyte with the removal of such a dangerous impurity as arsenic in a form suitable for the intended use. Using probabilistic deterministic planning of the experiment, the course of chemical reactions in manganese- and arsenic-containing systems, the directions of reactions and the stability of their constituent phases were studied. Based on experimental data and thermodynamic analysis, the probable behavior of chemical elements and their compounds, the limits of potential and pH, within which a given compound of an element must be stable, are determined. X-ray diffraction identified the formation of manganese arsenate (Mn3(AsO4)2·4H2O) in deposits formed during the extraction of arsenic from a copper electrolyte with manganese (IV) oxide. [ABSTRACT FROM AUTHOR]

In the context of marketability, economic value, and agricultural effectiveness to meet the feed demand of animal husbandry, it is necessary to create a solid forage base in the Kyzylorda region, Kazakhstan. The thriving solution to increased livestock and animal husbandry productivity in ecological conditions of the Aral Sea region principally depends upon the timely procurement of feed and the establishment of industrial-based feed production. Producing enhanced high-quality feeds can be the outcome of introducing high-yielding varieties, using new resource-saving cultivation and harvesting technologies, organizing optimal cultivation and production processes, and increasing the efficiency of various technical means. Of all the harvested types of feeds, alfalfa (Medicago sativa L.) has the best effect on increasing the livestock's milk and meat yield. All farm animals can also consume the green mass of alfalfa much faster. In feeding cattle with alfalfa, its utilization rate is 92.6%. On biochemical composition, alfalfa hay surpasses various other feeds, and 100 kg of alfalfa hay contains 11.6 kg of digestible protein, 1.77 kg of calcium, 0.22 kg of phosphorus, and 4.5 g of carotene. In conditions with rice crop rotation and according to its biological characteristics, alfalfa is indispensable in agrotechnical and reclamation relations, especially in saline soils. The economic value of alfalfa lies in its broad ecological plasticity, high productivity, and ability to grow back quickly after mowing. [ABSTRACT FROM AUTHOR]

Background: Hepatitis C virus (HCV) interferes with activation of innate and adaptive immune responses. Theoretically, the efficacy and toxicity of immune checkpoint inhibitors in cancer patients infected with HCV may differ. Nevertheless, HCV was an exclusion criterion in most checkpoint inhibitor trials. We evaluated the efficacy and safety of nivolumab in metastatic renal cell carcinoma (mRCC) patients with or without chronic HCV infection., Methods: In a matched cohort study, data were collected from 174 patients, retrospectively. All patients had clear-cell mRCC, chronic HCV infection (case study group), no evidence of other malignancy or cirrhosis, and had received nivolumab (3 mg/kg every 2 weeks) until disease progression or unacceptable toxicity. Quantitation of HCV RNA in plasma samples was performed before and during treatment with nivolumab with the automated HCV test (Hoffmann-La Roche, Switzerland). The primary endpoint was overall survival (OS). Secondary endpoints included progression-free survival (PFS), objective response rate (ORR), and rate of grade 3-4 adverse events in study and control cohorts., Results: A total of 44 matched patients were included. Groups were well balanced. HCV-infected patients had significantly longer OS and PFS. Median OS was 27.5 (95% CI 25.3-29.7) and 21.7 (20.3-23.1) in study and control groups, respectively (P = 0.005). Median PFS was 7.5 (5.7-9.3) and 4.9 (4-5.8) (P = 0.013). Despite no differences in ORR between groups (27% vs. 23%, P = 0.7), patients with HCV had significantly more durable responses (P = 0.01). Nivolumab was well tolerated in all HCV-positive patients. No unexpected toxicity was observed. Assessment of viral load during nivolumab therapy was available in 14 of 22 (64%) patients with HCV. Nivolumab did not significantly impact HCV concentration (mean change 210 IU/ml, P = 0.82) in the absence of antiviral therapy., Conclusions: The efficacy and safety profiles observed in this study support the administration of nivolumab in mRCC patients infected with HCV and warrant further investigation.

Background: Issues of mass screening for prostate cancer rather controversial since 2013 in 11 regions of Kazakhstan introduced a population-based screening for prostate cancer, so we need to evaluate its results., Methods: In different regions of Kazakhstan during 2013-2015, a total of 321548 prostate-specific antigens (PSA) were determined in men aged 50-66 yr, under the Prostate Health Index (PHI) and transrectal ultrasonography (TRUS) guided prostate biopsy with histological examination., Results: PSA level up to 4 ng/ml in 310870 (96.7%) men, PSA level between 4 and 10 ng/ml in 8 624 (2.7%) men, PSA level above 10 ng/ml in 2054 (0.6%) men. PHI was identified in 5716 (1.8%) men, of which 2867 cases were with PHI ≥ 25 (35.9%). Totally, 3680 biopsies (1.1%) of the prostate were performed. As part of the screening, 2870 cases (0.88%) of benign prostatic hyperplasia and prostatic intraepithelial neoplasia were found. Of 742 cases of prostate cancer (0.23%) were revealed. The stages of prostate cancer screening were as follows: stage I in 172 men (23.2%), stage II in 444 men (59.8%), stage III in 98 men (13.2%) and stage IV in 28 (3.8%) men. The indicators of prostate cancer early diagnosis in the I-II stages were bigger in the "screening regions" than in the "traditional diagnostics" regions: RR 1.35 95% CI (1.24 - 1.46), OR 1.84 95% CI (1.58-2.15). Prostate cancer was detected at I-II stages in the "screening" regions only by screening vs traditional diagnostics, with RR 1.64 95% CI (1.56 - 1.73), OR 4.77 95% CI (3.87-5.87)., Conclusion: Implementation of screening can improve the diagnosis of prostate cancer in the early stages., Competing Interests: Conflict of Interests The authors declare that there is no conflict of interests.