Papers by Sholpan Nazarkulova
Химический журнал Казахстана, Jun 15, 2022
Introduction. Due to the application of fertilizers, not only additional pollutants are added to ... more Introduction. Due to the application of fertilizers, not only additional pollutants are added to the soil of agricultural lands, but also the mobility of pollutants increases due to their transformation into geochemically mobile forms, which allow them to penetrate through the root system into edible parts of plants and accumulate through food chains in biological systems, including the human body. The purpose of this work is to study the effect of using mineral fertilizers on the species of metals in soils and prediction of their mobility. Methodology. Soil samples selected from the Almaty region (Baiterek village) of the Republic of Kazakhstan were studied by applying ammonium nitrate and monopotassium phosphate fertilizers. The species of metals and radionuclides (polonium-210 and lead-210) were studied according to the method of sequential extraction proposed by A. Tessier. The content of metals in solutions determined by inductively coupled plasma mass spectrometry on an Agilent 7500a spectrometer (USA). The activity concentration of polonium-210 and lead-210 were determined by alphabeta radiometer. Results and discussion. In the presence of monopotassium phosphate, the proportion of the geochemically inert fraction of alkali and alkaline earth metals is lower (2.52%, 10.8%, and 5.5% for calcium, barium, and strontium, respectively) than in the case of using ammonium nitrate and in the absence of fertilizers. For heavy metals, the smallest proportion of the geochemically inert (acid-soluble) fraction was observed for the sample without the use of fertilizers (71.25% for iron, 26.84% for copper, 16.40% for zinc, and 25.96% for lead). Conclusion. Using the fertilizers insignificantly affects the species of alkali metals, polonium-210, and lead-210. While application of monopotassium phosphate increases the geochemical mobility of sodium and alkaline earth elements due to the transition to the water-soluble and exchangeable fractions, and heavy metals due to the transition to the exchangeable fraction.
ABM Proceedings
This property has been studied to characterize the strength a metallic material exhibits when it ... more This property has been studied to characterize the strength a metallic material exhibits when it is machined so it can be regarded as its typical behaviour. As such, it may even be considered as an intrinsic material property. It is usually measured by an index called Coppini index, which is expressed by the ratio between the removed mass of a cutting tool caused by wear when it is used for machining and its initial one for a certain set of machining parameters. In this investigation, the tests were therefore conducted by an established set of parameters, namely feed rate, cutting and depth rates, in which the same wear mechanism took place in both ferrous alloys: AISI 4140 and AISI 316 steels. They were chosen based upon their increasing ordinary machinability indexes. The initial and final mass of the cutting tool were measured by an analytical scale with 0.01 mg precision. Cylindrical rods of 50-mm diameter were machined and the CI indexes showed a remarkable difference between them: 0.080 for the first steel and 0.049 for the second one, i.e., AISI 316 steel presented better machinability than the first one. It was then possible to conclude that this method presents good results in terms of both reproducibility and adequacy for machine shop conditions and it may be applied in a foreseeable future, mainly for metallic materials that have rather low machinability indices.
Food Additives & Contaminants: Part B, 2022
Natural uranium isotopes were determined in food products of the Kyzylorda region in Kazakhstan. ... more Natural uranium isotopes were determined in food products of the Kyzylorda region in Kazakhstan. This region is characterised by the influence of the uranium industry, as up to 15% of the world uranium reserves are concentrated in this part of Kazakhstan and the adjacent territory of Kyrgyzstan. The food products most consumed by locals were selected for this survey. Special attention was paid to the analysis of edible and non-edible parts of food products and the assessment of a possible increase in risk due to consumption of non-edible parts. The highest content of uranium, of 80.2 µg/kg, was found in the edible part of the carrot. The highest activity concentrations of uranium isotopes are found in carrot, potato and onion, as edible parts of these vegetables are grown in the soil. All estimated cancer risks for uranium isotopes range from 10−14 to 10−12, which are insignificant values.
Boron compounds are applied in different industries due to their fire retardancy, heat resistance... more Boron compounds are applied in different industries due to their fire retardancy, heat resistance, nonlinear optics and antiwear properties. The extraction of boron from natural waters in the form of boric acid can relieve the increasing consumption of this element. The optimal conditions of solid extraction of boron from natural waters by caprylic and stearic acid with different carriers (mannitol and paraffin) are investigated. The effect of the temperature and the phase contacts number is presented. The optimal temperature is found equal to 60oC. The best results are obtained at the 3rd phase contact: up to 74.12 % in case of the “fatty acids-paraffin” system.
BIO Web of Conferences, 2021
Increased demand for agricultural products leads to soil depletion and increased use of mineral a... more Increased demand for agricultural products leads to soil depletion and increased use of mineral and organo-mineral fertilizers. Mineral fertilizers used in agriculture may contain contaminators such as heavy metals or radionuclides that can migrate and accumulate in plants. Although migration and accumulation abilities directly depend on species in which they are presented. Determination of species of heavy metals and radionuclides can be done by sequential extraction technique, which takes long time and a lot of reactants. Preliminary evaluation can be done on the basis of data of simultaneous thermal analysis. In the present study the simultaneous thermal analysis was used for investigation of mineral fertilizers, purchased in Almaty. “Fasko” with ammonia nitrate and “Bujskie udobreniya” fertilizers contain water-soluble fractions and “Ljubo zeleno” and “Fertika” contain organic soluble fractions.
Chemical Bulletin of Kazakh National University, 2015
В работе представлены результаты определения изотопов урана в водных объектах региона Каджи-Сай, ... more В работе представлены результаты определения изотопов урана в водных объектах региона Каджи-Сай, где расположен бывший урановый рудник, обогатительная фабрика и хвостохранилище с общим объемом 400000 м 3. Определение изотопов урана проводилось альфа-спектрометрическим методом с предварительной радиохимической подготовкой (соосаждение на гидроксиде железа, экстракция трибутилфосфатом и электроосаждение на диск из нержавеющей стали) на альфа-спектрометре фирмы «Canberra». На основании экспериментальных данных были рассчитаны соотношения урана-234 к урану-238, построена и изучена уран-изотопная диаграмма определения генетического состава вод. В ходе работы установлено три генетических типа вод: воды глубинной циркуляции, воды урановой аномалии, дренирующие хвостохранилище, и воды активного водообмена региона. Рассчитаны пропорции их смешения в исследованных водоисточниках. Установлено, что питьевые воды поселка Каджи-Сай лишь на 5-7% состоят из вод, обогащенных ураном, преимущественную часть (60-80%) составляют воды глубинной циркуляции. Ключевые слова: Каджи-Сай; изотопы урана; рудник; уран-изотопное соотношение; генетический состав вод.
Journal of environmental monitoring : JEM, 2012
The concentrations of (238)U, (234)U, (226)Ra, (210)Po and (210)Pb have been determined in surfac... more The concentrations of (238)U, (234)U, (226)Ra, (210)Po and (210)Pb have been determined in surface waters collected along the course of the Shu River, lying on the border between Kazakhstan and Kyrgyzstan. In the study area, the river runs through some of the largest uranium deposits worldwide, which were actively exploited during the nuclear weapons and nuclear energy programmes of the former Soviet Union. The data show an increasing trend in uranium concentrations downstream the river from the city of Tokmak to the city of Shu, with good correlation between total uranium concentrations and total dissolved solids. Data on uranium isotopes disequilibrium show the presence of technogenic uranium inputs into the Shu River downstream from the city of Karasu, evidenced by a decrease in the measured (234)U/(238)U isotopic ratio from 1.63 in uncontaminated sites to 1.29 in sites affected by past mining activities.
SGEM2011 11th International Multidisciplinary Scientific GeoConference, 2011
13th SGEM GeoConference on ECOLOGY, ECONOMICS, EDUCATION AND LEGISLATION, 2013
Uploads
Papers by Sholpan Nazarkulova