I. Matveyeva, N. Nursapina, T. Tuzova, B. Shynybek
{"title":"Isotopes of uranium in waters and ice of Pamir–Alai","authors":"I. Matveyeva, N. Nursapina, T. Tuzova, B. Shynybek","doi":"10.15328/cb1006","DOIUrl":"https://doi.org/10.15328/cb1006","url":null,"abstract":"The article presents the results of determination of concentration and isotope composition of uranium in waters and ice of the Pamiro-Alai. The obtained experimental data are the background for studying of the regularities of the formation of the effluent of mountain rivers. This work is significant because of the studied region is transboundary and is under the interest of the neighboring countries. Sampling was carried out during fieldwork in 2016 under the USAID-Afghanistan PEER454 project. Determination of uranium isotopes was carried out using high-resolution alpha-spectrometry after radiochemical isolation and purification. The main objects of this study are Kyzylsu and Muksu rivers with their tributaries, as well as the ice of this region. Three genetic types were determined based on the obtained experimental data. The first type includes atmospheric precipitations and young ice (ice from the glacier of Lenin and a spring near the Ters-Agar passage). The second type of water is characteristic for waters having contact with uranium-enriched rocks (the estuary of Kashkasu river). The third type of water is waters of deep circulation with active water exchange in mountain ranges with a high uranium concentration (eastern springhead of the Kyzylsu river). The calculations showed that the main source of most of the studied water bodies are atmospheric precipitations.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2018-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47743478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Seitzhanova, D. I. Chenchik, M. Yeleuov, Z. Mansurov, R. Capua, N. S. Elibaeva
{"title":"Synthesis and characterization of graphene layers from rice husks","authors":"M. Seitzhanova, D. I. Chenchik, M. Yeleuov, Z. Mansurov, R. Capua, N. S. Elibaeva","doi":"10.15328/CB986","DOIUrl":"https://doi.org/10.15328/CB986","url":null,"abstract":"In this work, a method of obtaining graphene layers from natural source specifically from rice husk was developed. A rice husk (RH) was used as a raw material, and potassium hydroxide was used as activation agent. The graphene layers were obtained after four successive stages: pre-carbonization, desilication in 1M NaOH solution, chemical activation and exfoliation of the carbonized rice husk (CRH). The obtained samples were studied using Raman spectroscopy, TEM and SEM; the Raman peaks evidenced the presence of graphene multilayers in the sample. A detailed observation of Raman spectroscopy showed that the obtained samples with ratio of 1/4 and 1/5 (RH/KOH) consisted of graphene layers with a high content of amorphous component. The yield of the product was ~ 3% by weight. This study can provide a new way to the large-scale synthesis of low-cost single and multi-layered graphene using rice husk or other renewable resources.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2018-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42198679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kh. S. Tassibekov, Zhenis Zh. Bekishev, R. Tokpayev, K. K. Kishibaev, A. Ismailova, S. Nechipurenko, S. Efremov, M. Nauryzbayev
{"title":"Mechanism of the thermochemical transformation of wheat grain’s processing waste during heat treatment","authors":"Kh. S. Tassibekov, Zhenis Zh. Bekishev, R. Tokpayev, K. K. Kishibaev, A. Ismailova, S. Nechipurenko, S. Efremov, M. Nauryzbayev","doi":"10.15328/cb1007","DOIUrl":"https://doi.org/10.15328/cb1007","url":null,"abstract":"The thermal destruction of wheat grain’s processing wastes from Almaty and South Kazakhstan regions was studieв. The structure of the products obtained depending on the temperature of the carbonization process was formed, and the basic physico-chemical characteristics of the obtained carbon material based on the WGPW were studied using thermogravimetric analysis, differential scanning calorimetry, IR spectroscopy and EPR spectroscopy. The analysis of the elemental composition of the obtained samples of the sorption material showed that the carbon content in the composition of the obtained carbon material is 75.08 - 76.12%, which in turn can cause a sufficiently high degree of sorption capacity of this material, as well as its mechanical strength. The obtained carbon materials based on OIP were modified with ammonium nitrate (NH4NO3) to improve its physico-chemical characteristics, such as specific surface area, porosity and adsorption capacity by iodine. It is shown that structural transformations of the processing waste of wheat grain (bran) in the process of heat treatment irrespective of temperature (in the studied interval) proceed through the stage of formation of free radicals. The concentration of free radicals formed in this process, as well as the composition of the graphite-like component of the products obtained, are determined by the temperature indices of the process.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2018-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44343609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Quantification of transformation products of unsymmetrical dimethylhydrazine in aqueous extracts from soil\u0000based on vacuum-assisted headspace solid-phase microextraction","authors":"D. Orazbayeva, B. Kenessov, A. Zhakupbekova","doi":"10.15328/CB1014","DOIUrl":"https://doi.org/10.15328/CB1014","url":null,"abstract":"Quantification of transformation products of unsymmetrical dimethylhydrazine (UDMH) in soil requires tedious, time- and labor-consuming sample preparation. The simple and fast method for quantification of transformation products of UDMH in aqueous extracts from soil using vacuum-assisted headspace solid-phase microextraction (Vac-HSSPME) was optimized in this work. The method is based on extraction of analytes from soil with water followed by Vac-HSSPME of the obtained aqueous extracts, and gas chromatography-mass spectrometry analysis. The target transformation products were: pyrazine, 1-methyl-1H-pyrazole, N-nitrosodimethylamine, N,N-dimethylformamide, 1-methyl-1Н-1,2,4-triazole, 1-methyl-imidazole and 1H-pyrazole. The effect of a sample pH on responses of target analytes was studied. It was negligible, and no pH adjustment was recommended before a subsequent extraction. The water amount was optimized to provide the best combination of analytes responses and their precision. Extraction by adding 7.00 mL of water to 2.0 g of soil ensured linear dependence of responses of the analytes on their concentrations in soil. The optimized method provided detection limits of target analytes in soil in the range from 0.2 to 9 ng/g. The spike recoveries obtained for model samples were in the range 90-103%. The developed method can be recommended for application in laboratories conducting routine analyses of soil samples potentially contaminated by rocket fuel residuals.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2018-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44098538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}