Zhandos K. Orazov, Yerzhigit Tulebekov, Askar M. Bakhadur, Bolat M. Uralbekov
Проведено исследование кинетики фотокаталитического разложения красителя (Orange II) в присутствии диоксида титана (IV). Представлена кинетическая модель, учитывающая активные формы частиц, участвующих в процессе фотокаталитического окисления. Путем добавления различных реагентов-поглотителей было установлено, что супероксид радикалы (O2•-) играют наиболее значимую роль в фотодеградации красителя. В качестве поглотителей гидроксид радикалов (•OH), дырок (h+), синглетного кислорода (1O2), супероксид радикалов (O2•-) и электронов (e-) использовались терт-бутанол (t-BuOH), оксалат аммония (ОА), азид натрия (NaN3), 4-Hydroxy-TEMPO (TEMPOL) и диметилсульфоксид (ДМСО) с конечной концентрацией 10 мМ в 40 мл раствора Orange II. Предложенная кинетическая модель включает следуюшие этапы: фотогенерация частиц, образование супероксид радикалов и их взаимодействие с органическим красителем, продуктами и неактивными поверхностями. Проведенные исследования по определению кинетических параметров реакции, в частности, порядка по Orange II, показали, что реакция имеет псевдо-первый порядок, что хорошо согласуется с предложенной кинетической моделью. Полученная линейная зависимость ln(C0/C) от времени показывает, что реакцию фоторазложения Orange II можно отнести к реакции псевдо-первого порядка, константа скорости которой равна (35,1±1,3).10-3 мин-1.
研究了一种染料（橙色 II）在二氧化钛（IV）存在下的光催化分解动力学。研究提出了一个动力学模型，其中考虑到了参与光催化氧化过程的颗粒的活性形式。通过添加不同的吸收试剂，发现超氧自由基（O2--）在染料的光降解过程中起着最重要的作用。叔丁醇（t-BuOH）被用作氢氧自由基（-OH）、空穴（h+）、单线态氧（1O2）、超氧自由基（O2--）和电子（e-）的吸收剂、在 40 毫升橙 II 溶液中加入最终浓度为 10 毫摩尔的草酸铵（OA）、叠氮化钠（NaN3）、4-羟基-TEMPO（TEMPOL）和二甲基亚砜（DMSO）。提出的动力学模型包括以下步骤：粒子光生成、超氧自由基的形成及其与有机染料、产物和非活性表面的相互作用。对反应动力学参数，特别是橙 II 阶数的测定研究表明，该反应为伪一阶反应，这与所提出的动力学模型十分吻合。ln(C0/C) 与时间的线性关系表明，橙 II 的光降解反应属于伪一阶反应，其速率常数为 (35.1±1.3).10-3 min-1。
{"title":"Кинетическая модель фотокаталитического окисления красителя (Orange II) супероксид радикалами","authors":"Zhandos K. Orazov, Yerzhigit Tulebekov, Askar M. Bakhadur, Bolat M. Uralbekov","doi":"10.15328/cb1345","DOIUrl":"https://doi.org/10.15328/cb1345","url":null,"abstract":"Проведено исследование кинетики фотокаталитического разложения красителя (Orange II) в присутствии диоксида титана (IV). Представлена кинетическая модель, учитывающая активные формы частиц, участвующих в процессе фотокаталитического окисления. Путем добавления различных реагентов-поглотителей было установлено, что супероксид радикалы (O2•-) играют наиболее значимую роль в фотодеградации красителя. В качестве поглотителей гидроксид радикалов (•OH), дырок (h+), синглетного кислорода (1O2), супероксид радикалов (O2•-) и электронов (e-) использовались терт-бутанол (t-BuOH), оксалат аммония (ОА), азид натрия (NaN3), 4-Hydroxy-TEMPO (TEMPOL) и диметилсульфоксид (ДМСО) с конечной концентрацией 10 мМ в 40 мл раствора Orange II. Предложенная кинетическая модель включает следуюшие этапы: фотогенерация частиц, образование супероксид радикалов и их взаимодействие с органическим красителем, продуктами и неактивными поверхностями. Проведенные исследования по определению кинетических параметров реакции, в частности, порядка по Orange II, показали, что реакция имеет псевдо-первый порядок, что хорошо согласуется с предложенной кинетической моделью. Полученная линейная зависимость ln(C0/C) от времени показывает, что реакцию фоторазложения Orange II можно отнести к реакции псевдо-первого порядка, константа скорости которой равна (35,1±1,3).10-3 мин-1.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139309643","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}
The lack of data systematization on the coexistence and stability of compounds formed in the SrO – GdO1.5 – FeO1.5 system at temperatures above 1100°C determines the interest in a more detailed study of this system. The research was focused on studying the stability of phases formed in the pseudobinary section (1-х)GdFeO3 – хSrO in the temperature range 1200- 1400°C in air. The interaction of components in the SrO – GdO1.5 – FeO1.5 system was studied by the method of annealing and quenching followed by physicochemical analysis. The phase composition and sequence of phase transformations were characterized by powder X-ray diffraction. Phase relations results in the SrO – GdO1.5 – FeO1.5 system in air were systematized. The formation of three complex perovskite-like oxides GdSr2FeO5, GdSrFeO4, Gd2SrFe2O7, located on the GdFeO3 – SrO binary section was established. Information on interplanar distances and reflection intensities of the GdSr2FeO5 compound has been supplemented and the existence of a miscibility gap for Gd1-xSrxFeO3-α solid solutions existing in the range 0.05≤x≤0.51 at 1400°C has been shown. Data on thermal stability of complex gadolinium ferrites based on GdO1.5 – SrO – FeO1.5 system has been expanded.
{"title":"Phase relations in the SrO – GdO1.5 – FeO1.5 system","authors":"K. Kenges, Valentina Popova, Ekaterina Тugova","doi":"10.15328/cb1335","DOIUrl":"https://doi.org/10.15328/cb1335","url":null,"abstract":"The lack of data systematization on the coexistence and stability of compounds formed in the SrO – GdO1.5 – FeO1.5 system at temperatures above 1100°C determines the interest in a more detailed study of this system. The research was focused on studying the stability of phases formed in the pseudobinary section (1-х)GdFeO3 – хSrO in the temperature range 1200- 1400°C in air. The interaction of components in the SrO – GdO1.5 – FeO1.5 system was studied by the method of annealing and quenching followed by physicochemical analysis. The phase composition and sequence of phase transformations were characterized by powder X-ray diffraction. Phase relations results in the SrO – GdO1.5 – FeO1.5 system in air were systematized. The formation of three complex perovskite-like oxides GdSr2FeO5, GdSrFeO4, Gd2SrFe2O7, located on the GdFeO3 – SrO binary section was established. Information on interplanar distances and reflection intensities of the GdSr2FeO5 compound has been supplemented and the existence of a miscibility gap for Gd1-xSrxFeO3-α solid solutions existing in the range 0.05≤x≤0.51 at 1400°C has been shown. Data on thermal stability of complex gadolinium ferrites based on GdO1.5 – SrO – FeO1.5 system has been expanded.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139341171","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}
Madina Suleimenova, Saule Zharylkan, Meruyert Mekenova, Aidana Tolepova, Alibek Mutushev, S. Azat, Tauanov Zhandos
The article presents the results of the development of new composite materials obtained from rice husk ash (ZRH). Composite materials are bound by 2 wt.% silver nanoparticles and characterized using methods for determining their structural characteristics, namely: X-ray fluorescence analysis (XRF), scanning electron microscopy with elements of semi-quantitative analysis (SEM-EDS), low-temperature nitrogen adsorption (according to the theory of Brunauer-Emmett-Teller (BET) and X-ray phase analysis (XRD). According to the results of the elemental semi-quantitative analysis, the zeolite was successfully modified with silver nanoparticles, which at co-deposition amounted to 1.44%. Mineralogical phases were determined in an X-ray diffractometer (XRD) and the pronounced crystal structure of synthetic zeolite of the form "analcim" and silver nanoparticles was confirmed. A structural modification of synthetic zeolite “analcime” based on ZRH was carried out in order to quickly bind zeolite with mercury. The BET results showed the formation of mesopores and micropores, while the surface area of synthetic zeolite and modified silver nanoparticles (AgNPs) was 48.94 m2/g and 0.75 m2/g, respectively. Preliminary results showed that the removal of mercury ions from the solution was from 20 to 50% of the initial concentration.
{"title":"Obtaining synthetic zeolite and nanocomposite from rice husk to remove mercury ions from water","authors":"Madina Suleimenova, Saule Zharylkan, Meruyert Mekenova, Aidana Tolepova, Alibek Mutushev, S. Azat, Tauanov Zhandos","doi":"10.15328/cb1323","DOIUrl":"https://doi.org/10.15328/cb1323","url":null,"abstract":"The article presents the results of the development of new composite materials obtained from rice husk ash (ZRH). Composite materials are bound by 2 wt.% silver nanoparticles and characterized using methods for determining their structural characteristics, namely: X-ray fluorescence analysis (XRF), scanning electron microscopy with elements of semi-quantitative analysis (SEM-EDS), low-temperature nitrogen adsorption (according to the theory of Brunauer-Emmett-Teller (BET) and X-ray phase analysis (XRD). According to the results of the elemental semi-quantitative analysis, the zeolite was successfully modified with silver nanoparticles, which at co-deposition amounted to 1.44%. Mineralogical phases were determined in an X-ray diffractometer (XRD) and the pronounced crystal structure of synthetic zeolite of the form \"analcim\" and silver nanoparticles was confirmed. A structural modification of synthetic zeolite “analcime” based on ZRH was carried out in order to quickly bind zeolite with mercury. The BET results showed the formation of mesopores and micropores, while the surface area of synthetic zeolite and modified silver nanoparticles (AgNPs) was 48.94 m2/g and 0.75 m2/g, respectively. Preliminary results showed that the removal of mercury ions from the solution was from 20 to 50% of the initial concentration.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139367969","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}
Gulzhan Yerlan, B. Tyussyupova, S. Tazhibayeva, K. Musabekov
Diabetes mellitus is among the top ten leading causes of death worldwide and remains a serious health problem. More than half a billion people worldwide have diabetes, which occurs when the body is unable to produce insulin or due to the inefficient use of the produced insulin. To keep blood glucose levels within the acceptable norm, people with type 1 diabetes need daily injections of insulin. Even though insulin remains an indispensable drug in the treatment of diabetes, its injectable form prevents its wider use. To eliminate the barriers associated with the injectable form of insulin, improve ease of use, and supply therapeutic benefits, a lot of work is underway to create an oral form of insulin. This review is devoted to the presentation of general information about modern achievements in the creation of an oral form of insulin. The paper describes the prevalence of diabetes mellitus and its treatment, methods of protein encapsulation, difficulties in the use of oral insulin, as well as various approaches that have been taken to overcome barriers to the creation of an oral form of insulin. The latest achievements in the use of mucoadhesive polymers and hydrogels for drug delivery are considered. Mucoadhesive polymers such as chitosan and alginate are attracting increasing attention due to their properties such as pH sensitivity, biocompatibility, and biodegradability. Methods of encapsulation of protein drugs with the use of spray drying, emulsification, and deposition of polymer materials by complexation are presented.
{"title":"Polymer systems for oral delivery of insulin","authors":"Gulzhan Yerlan, B. Tyussyupova, S. Tazhibayeva, K. Musabekov","doi":"10.15328/cb1298","DOIUrl":"https://doi.org/10.15328/cb1298","url":null,"abstract":"Diabetes mellitus is among the top ten leading causes of death worldwide and remains a serious health problem. More than half a billion people worldwide have diabetes, which occurs when the body is unable to produce insulin or due to the inefficient use of the produced insulin. To keep blood glucose levels within the acceptable norm, people with type 1 diabetes need daily injections of insulin. Even though insulin remains an indispensable drug in the treatment of diabetes, its injectable form prevents its wider use. To eliminate the barriers associated with the injectable form of insulin, improve ease of use, and supply therapeutic benefits, a lot of work is underway to create an oral form of insulin. This review is devoted to the presentation of general information about modern achievements in the creation of an oral form of insulin. The paper describes the prevalence of diabetes mellitus and its treatment, methods of protein encapsulation, difficulties in the use of oral insulin, as well as various approaches that have been taken to overcome barriers to the creation of an oral form of insulin. The latest achievements in the use of mucoadhesive polymers and hydrogels for drug delivery are considered. Mucoadhesive polymers such as chitosan and alginate are attracting increasing attention due to their properties such as pH sensitivity, biocompatibility, and biodegradability. Methods of encapsulation of protein drugs with the use of spray drying, emulsification, and deposition of polymer materials by complexation are presented.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44427246","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}
K. Bedelbekova, S. Lennik, Yevgeniy Sokolenko, T. Suzdaltseva
The neutron activation analysis for short-lived radionuclides at the WWR-K uses a pneumatic transport system (Austria) with specific transport capsules. The irradiated samples are not removed from the transport capsules and are measured directly in the capsule. It is necessary to take into account the fact that the induced activity of the capsule material itself acts as the background radiation in relation to the induced activity of the sample under study. A study of the capsule material and the polyethylene tubes used as sample fixing devices in the center of the transport capsule was performed. Earlier it was found that the HDPE T50 capsule material contains impurity elements Ti, Cl, Al, Na, Ca. It was found that the fixing material contains a larger amount of impurities, which leads to the increase of spectrometric equipment loading and to the increase of relative contribution of individual radionuclides to the final spectrum. The induced activity spectra were analyzed and processed, the content of elements in polyethylene was calculated and it was shown that the analytical signals of Mg-27, Mn-56 and Sb-122m, Cr-51 and Sb-122 refer exclusively to the induced activity of the fixer-tube material. This circumstance does not allow to determine small concentrations of these elements in the samples themselves. The necessity of search of other more pure material for its use as sample fixers at placement in a transport capsule is shown.
{"title":"Use of polyethylene consumables in neutron activation analysis for short-lived radionuclides","authors":"K. Bedelbekova, S. Lennik, Yevgeniy Sokolenko, T. Suzdaltseva","doi":"10.15328/cb1318","DOIUrl":"https://doi.org/10.15328/cb1318","url":null,"abstract":"The neutron activation analysis for short-lived radionuclides at the WWR-K uses a pneumatic transport system (Austria) with specific transport capsules. The irradiated samples are not removed from the transport capsules and are measured directly in the capsule. It is necessary to take into account the fact that the induced activity of the capsule material itself acts as the background radiation in relation to the induced activity of the sample under study.\u0000\u0000A study of the capsule material and the polyethylene tubes used as sample fixing devices in the center of the transport capsule was performed. Earlier it was found that the HDPE T50 capsule material contains impurity elements Ti, Cl, Al, Na, Ca. It was found that the fixing material contains a larger amount of impurities, which leads to the increase of spectrometric equipment loading and to the increase of relative contribution of individual radionuclides to the final spectrum. The induced activity spectra were analyzed and processed, the content of elements in polyethylene was calculated and it was shown that the analytical signals of Mg-27, Mn-56 and Sb-122m, Cr-51 and Sb-122 refer exclusively to the induced activity of the fixer-tube material. This circumstance does not allow to determine small concentrations of these elements in the samples themselves. The necessity of search of other more pure material for its use as sample fixers at placement in a transport capsule is shown.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47550792","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}
E. Yergaliyeva, K. Bazhykova, Saltanat B. Abeuova, V. Vazhev, Peter Langer
This paper presents the results of predicting drug-likeness, biological activity, and toxicity for 8 new derivatives of 3,5-bis(hydroxymethyl)tetrahydro-4H-pyran-4-one using bioinformatic methods. The physicochemical and pharmacokinetic parameters of the studied compounds were determined, in silico screening for biological activity and prediction of their toxicity were carried out. Physicochemical and pharmacokinetic parameters were evaluated using the Molinspiration Cheminformatics service. It was found that compounds 1–11 corresponded to Lipinski’s rule for drug-like compounds. As predicted in Molinspiration, compound 4 exhibits significant biological activity as a possible enzyme inhibitor and G-protein coupled receptor ligand. Compound 6 is active as an ion channel modulator. Virtual PASS screening identified compounds with potential antidiabetic activity (1–3, 5–8) and activity in the treatment of phobic disorders and dementias (1–5, 7, 8, 11). Compound 1 can potentially act as a substrate for CYP2H, and inhibitors of enzymes of the peptidase group are 1, 3, 4, 6, 7, 11. As a result of QSAR prediction based on LD50 values calculated in ProTox-II, compound 10 belongs to class 6; compounds 1–3, 5 and 8 belong to the 5th class of toxicity; compounds 6 and 9 belong to the 4th class. Compound 4 belongs to class 3. Compounds 1–9 do not exhibit the toxicities shown in the ProTox-II models. Compounds 10 and 11 may be carcinogenic.
{"title":"In silico drug-likeness, biological activity and toxicity prediction of new 3,5-bis(hydroxymethyl)tetrahydro-4H-pyran-4-one derivatives","authors":"E. Yergaliyeva, K. Bazhykova, Saltanat B. Abeuova, V. Vazhev, Peter Langer","doi":"10.15328/cb1272","DOIUrl":"https://doi.org/10.15328/cb1272","url":null,"abstract":"This paper presents the results of predicting drug-likeness, biological activity, and toxicity for 8 new derivatives of 3,5-bis(hydroxymethyl)tetrahydro-4H-pyran-4-one using bioinformatic methods. The physicochemical and pharmacokinetic parameters of the studied compounds were determined, in silico screening for biological activity and prediction of their toxicity were carried out. Physicochemical and pharmacokinetic parameters were evaluated using the Molinspiration Cheminformatics service. It was found that compounds 1–11 corresponded to Lipinski’s rule for drug-like compounds. As predicted in Molinspiration, compound 4 exhibits significant biological activity as a possible enzyme inhibitor and G-protein coupled receptor ligand. Compound 6 is active as an ion channel modulator. Virtual PASS screening identified compounds with potential antidiabetic activity (1–3, 5–8) and activity in the treatment of phobic disorders and dementias (1–5, 7, 8, 11). Compound 1 can potentially act as a substrate for CYP2H, and inhibitors of enzymes of the peptidase group are 1, 3, 4, 6, 7, 11. As a result of QSAR prediction based on LD50 values calculated in ProTox-II, compound 10 belongs to class 6; compounds 1–3, 5 and 8 belong to the 5th class of toxicity; compounds 6 and 9 belong to the 4th class. Compound 4 belongs to class 3. Compounds 1–9 do not exhibit the toxicities shown in the ProTox-II models. Compounds 10 and 11 may be carcinogenic.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43119015","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}
Gulzhan Yerlan, B. Tyussyupova, S. Tazhibayeva, K. Musabekov, N. Balabushevich
The deformation properties, elastic modulus and strength of gelatin films with chitosan, citric acid and L-glutamic acid were studied. According to the results of the study, it was found that the addition of chitosan, citric and L-glutamic acid increases the strength and elasticity modulus of gelatin films. Assessment of the pH effect on the gelatin - chitosan, gelatin - citric acid and gelatin - L-glutamic acid systems provide a representation of their changes in these media. It is assumed that gelatin with L-glutamic acid forms a strong structure at low pH and withstands the conditions of the acidic environment of the stomach, while in an alkaline environment the structural and mechanical characteristics of this system decrease, creating favorable conditions for the release of encapsulated insulin in the intestinal phase. The changes of the physicochemical, structural and mechanical properties of the films under simulated gastrointestinal conditions (pH = 1.0; 4.01; 6.86; 9.18) were determined by IR spectroscopy. The observability of the bands of С-Н, С-ОН, С=O, C-N, N-H, СН(NH2), CH2OH groups in the infrared spectra of films in various pH media is associated with an increase of intermolecular hydrogen bonds and the formation of associative structures.
{"title":"Structural and mechanical properties of gelatin composite films","authors":"Gulzhan Yerlan, B. Tyussyupova, S. Tazhibayeva, K. Musabekov, N. Balabushevich","doi":"10.15328/cb1267","DOIUrl":"https://doi.org/10.15328/cb1267","url":null,"abstract":"The deformation properties, elastic modulus and strength of gelatin films with chitosan, citric acid and L-glutamic acid were studied. According to the results of the study, it was found that the addition of chitosan, citric and L-glutamic acid increases the strength and elasticity modulus of gelatin films. Assessment of the pH effect on the gelatin - chitosan, gelatin - citric acid and gelatin - L-glutamic acid systems provide a representation of their changes in these media. It is assumed that gelatin with L-glutamic acid forms a strong structure at low pH and withstands the conditions of the acidic environment of the stomach, while in an alkaline environment the structural and mechanical characteristics of this system decrease, creating favorable conditions for the release of encapsulated insulin in the intestinal phase. The changes of the physicochemical, structural and mechanical properties of the films under simulated gastrointestinal conditions (pH = 1.0; 4.01; 6.86; 9.18) were determined by IR spectroscopy. The observability of the bands of С-Н, С-ОН, С=O, C-N, N-H, СН(NH2), CH2OH groups in the infrared spectra of films in various pH media is associated with an increase of intermolecular hydrogen bonds and the formation of associative structures.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43524122","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}
N. Merkhatuly, A. Iskanderov, S. Zhokizhanova, Bibizhan Erniyazova
At present, non-benzenoid aromatic hydrocarbons are widely used as precursors for the synthesis of new materials with useful electronic properties. In particular, the non-alternative aromatic hydrocarbon azulen with a unique dipole structure and a tendency to form stabilized radical ions should be predetermined as a building block for obtaining new π-conjugated systems with interesting optoelectronic properties. This article discusses the directed synthesis and study of optical properties of new donor-acceptor compounds based on azulene. It was shown that for the synthesis of donor-acceptor phenylketone azulenes, the reaction of directed (to positions С1 and С3) acylation with benzoyl chloride in the presence of Li2MnCl4 in tetrahydrofuran was used for the first time as a key step. It was found that push-pull phenyldicyanovinyl azulenes obtained by Knoevenagel condensation of azulenylketones with malononitrile flow easily (with an increase in the yield of end products) in the presence of pyridine in dimethyl sulfoxide. Electron UV-visible spectra of phenyldicyanovinyl azulene compounds showed strong absorption bands in the visible region (λmax = 452 and 434 nm) caused by intense intramolecular charge transfer between the donor azulene ring and the acceptor phenyldicyanovinyl group.
{"title":"Synthesis of donor-acceptor compounds based on azulene","authors":"N. Merkhatuly, A. Iskanderov, S. Zhokizhanova, Bibizhan Erniyazova","doi":"10.15328/cb1299","DOIUrl":"https://doi.org/10.15328/cb1299","url":null,"abstract":"At present, non-benzenoid aromatic hydrocarbons are widely used as precursors for the synthesis of new materials with useful electronic properties. In particular, the non-alternative aromatic hydrocarbon azulen with a unique dipole structure and a tendency to form stabilized radical ions should be predetermined as a building block for obtaining new π-conjugated systems with interesting optoelectronic properties. This article discusses the directed synthesis and study of optical properties of new donor-acceptor compounds based on azulene. It was shown that for the synthesis of donor-acceptor phenylketone azulenes, the reaction of directed (to positions С1 and С3) acylation with benzoyl chloride in the presence of Li2MnCl4 in tetrahydrofuran was used for the first time as a key step. It was found that push-pull phenyldicyanovinyl azulenes obtained by Knoevenagel condensation of azulenylketones with malononitrile flow easily (with an increase in the yield of end products) in the presence of pyridine in dimethyl sulfoxide. Electron UV-visible spectra of phenyldicyanovinyl azulene compounds showed strong absorption bands in the visible region (λmax = 452 and 434 nm) caused by intense intramolecular charge transfer between the donor azulene ring and the acceptor phenyldicyanovinyl group.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46585105","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}
Headspace solid-phase microextraction (HSSPME) is one of the simplest and cost-efficient sample preparation approaches for determination of volatile organic compounds (VOCs) in soil. This study was aimed at the development of the model for numerical optimization of HSSPME of volatile organic compounds from dry soil samples by porous coatings using COMSOL Multiphysics (CMP). ‘Transport of Diluted Species in Porous Medium’ physics was used for modeling. Effect of sample mass, pressure, fiber-headspace and soil-headspace distribution constants on extraction profiles and time of 95% equilibrium has been studied using the developed model. Equilibrium extraction under atmospheric pressure (1 atm) can take up to 97 min, while under vacuum (0.0313 atm) – 2.3 min. Equilibration time under vacuum was 42-43 times lower than under 1 atm at all studied distribution constants and sample masses. The developed model was modified for optimization of pre-incubation time using ‘Transport of Diluted Species’ physics. According to the obtained plots, 95% equilibration time can reach 13.3 min and depends on both sample mass and soil-headspace distribution constant of the analyte. The developed model can be recommended for optimization of pressure, preincubation and extraction time when fiber-headspace and soil-headspace distribution constants, soil porosity and density are known.
{"title":"Optimization of headspace solid-phase microextraction of volatile organic compounds from dry soil samples by porous coatings using COMSOL Multiphysics","authors":"B. Kenessov, A. Kapar","doi":"10.15328/cb1300","DOIUrl":"https://doi.org/10.15328/cb1300","url":null,"abstract":"Headspace solid-phase microextraction (HSSPME) is one of the simplest and cost-efficient sample preparation approaches for determination of volatile organic compounds (VOCs) in soil. This study was aimed at the development of the model for numerical optimization of HSSPME of volatile organic compounds from dry soil samples by porous coatings using COMSOL Multiphysics (CMP). ‘Transport of Diluted Species in Porous Medium’ physics was used for modeling. Effect of sample mass, pressure, fiber-headspace and soil-headspace distribution constants on extraction profiles and time of 95% equilibrium has been studied using the developed model. Equilibrium extraction under atmospheric pressure (1 atm) can take up to 97 min, while under vacuum (0.0313 atm) – 2.3 min. Equilibration time under vacuum was 42-43 times lower than under 1 atm at all studied distribution constants and sample masses. The developed model was modified for optimization of pre-incubation time using ‘Transport of Diluted Species’ physics. According to the obtained plots, 95% equilibration time can reach 13.3 min and depends on both sample mass and soil-headspace distribution constant of the analyte. The developed model can be recommended for optimization of pressure, preincubation and extraction time when fiber-headspace and soil-headspace distribution constants, soil porosity and density are known.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41548168","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}
In this work, a two-step method for preparation of CZTSe (Cu2ZnSnSe4) single crystals was demonstrated for the first time by recrystallization of a polycrystalline material in a KI-KCl melt-solution in a temperature gradient. At the first step, a polycrystalline material consisting of a mixture of metal selenides was synthesized by direct fusion of elemental Cu, Zn, Sn, and Se at 1000°C. Next, recrystallization process was carried out at a temperature gradient of 100°C, while the temperature of the cold zone was 750°C. The phase and chemical composition of the crystals were studied by energy dispersive X-ray and Raman spectroscopy. It was shown that the charge composition does not affect the composition of the obtained crystals. According to the amount of the remaining charge in the hot zone, one can speak of a very low recrystallization rate and a low product yield. Analysis of the elemental composition of crystals from the cold zone revealed a high inhomogeneity even in one experiment, which indicates the need to optimize the experimental parameters. On the other hand, according to the full line width at half height of the main peak, it can be argued that the obtained samples have a high degree of order in the structure and are suitable for measuring of physical characteristics.
{"title":"Growth of Cu2ZnSnSe4 crystals from a KI-KCl melt-solution in a temperature gradient","authors":"A. Bakhadur, B. Uralbekov, K. Kokh","doi":"10.15328/cb1291","DOIUrl":"https://doi.org/10.15328/cb1291","url":null,"abstract":"In this work, a two-step method for preparation of CZTSe (Cu2ZnSnSe4) single crystals was demonstrated for the first time by recrystallization of a polycrystalline material in a KI-KCl melt-solution in a temperature gradient. At the first step, a polycrystalline material consisting of a mixture of metal selenides was synthesized by direct fusion of elemental Cu, Zn, Sn, and Se at 1000°C. Next, recrystallization process was carried out at a temperature gradient of 100°C, while the temperature of the cold zone was 750°C. The phase and chemical composition of the crystals were studied by energy dispersive X-ray and Raman spectroscopy. It was shown that the charge composition does not affect the composition of the obtained crystals. According to the amount of the remaining charge in the hot zone, one can speak of a very low recrystallization rate and a low product yield. Analysis of the elemental composition of crystals from the cold zone revealed a high inhomogeneity even in one experiment, which indicates the need to optimize the experimental parameters. On the other hand, according to the full line width at half height of the main peak, it can be argued that the obtained samples have a high degree of order in the structure and are suitable for measuring of physical characteristics.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49466875","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}
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