Chemical Bulletin of Kazakh National University最新文献

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Chemical composition and biological activity of Zosima absinthifolia (apiaceae) 苦艾的化学成分及生物活性
IF 0.3
Chemical Bulletin of Kazakh National University Pub Date : 2022-06-20 DOI: 10.15328/cb1266
N. Alikhanova, E. Novruzov
{"title":"Chemical composition and biological activity of Zosima absinthifolia (apiaceae)","authors":"N. Alikhanova, E. Novruzov","doi":"10.15328/cb1266","DOIUrl":"https://doi.org/10.15328/cb1266","url":null,"abstract":"Zosima absinthifolia (Vent.) Link is a perennial herb and is found in Iran, Turkey, Iraq and different countries of the Caucasus, Middle East and Central Asia. It is the only member of Zosima genus growing in Azerbaijan. It has been used as a medicinal plant since ancient time in Iran, Turkey and Pakistan. The fruits are used as a food flavoring and as a food spice in Iran. The knowledge of Z. absinthifolia organs containing a great number of bioactive compounds is of high importance. The aim of this study is to sum up literature data on the results of experimental studies of the chemical composition and biological activity of Z. absinthifolia. The results of the chemical study of Z. absinthifolia show that fruits, roots, seeds, flowers and other aboveground parts of plants are rich in various biologically active substances such as coumarins, furocoumarins, pyranocoumarins, flavonoids, monoterpenes, sesquiterpenes and etc. Chemical components that isolated from different organs of Z. absinthifolia have allelopathic, high antibacterial, antifungal, antioxidant, anti-inflammatory and other properties. Some of the chemical constituents have substantial pharmacological properties. It is clear that Z. absinthifolia has significant potential for useful natural supplements in many contemporary diseases.\u0000\u0000","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":" ","pages":""},"PeriodicalIF":0.3,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48158110","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}
引用次数: 0
Composition based on alicyclic copolymide and polyethylene terephthalate 基于脂环族共聚酰胺和聚对苯二甲酸乙二醇酯的组合物
IF 0.3
Chemical Bulletin of Kazakh National University Pub Date : 2022-03-28 DOI: 10.15328/cb1248
M. Umerzakova, R. Sarieva, A. Yespenbetov, Zh. N. Kainarbayeva
{"title":"Composition based on alicyclic copolymide and polyethylene terephthalate","authors":"M. Umerzakova, R. Sarieva, A. Yespenbetov, Zh. N. Kainarbayeva","doi":"10.15328/cb1248","DOIUrl":"https://doi.org/10.15328/cb1248","url":null,"abstract":"The addition of polymers such as polyethylene terephthalate, polycarbonate and polyurethane to another high molecular weight compound often provides improvement of properties of initial polymerfilms. These compounds can be successfully applied for obtaining of composite films based on polyimides. In the present work, conditions of making polymer composite films with arylalicyclic structured copolyimides and influence of polyethylene terephthalate on them were studied. It was found that, addition of component from 0.5 to 2 wt.% provides retaining of the polymers’ compatibility in the composite. Films formed from solutions of these compositions are transparent, brittleness of the material is not observed and there were little changes in elasticity compared with original copolyimide film. FTIR studies showed that the formation of these polymer blends leads to the interaction of functional groups of the polymers with hydrogen bonds, which determine the blend components compatibility. It has been found that, upon additional heat treatment of the films no more than 250°C, intermolecular crosslinking partially occurs with formation of an oxygen bridge between the amide acids of copolyimide and the added component. Such crosslinking provides increase of heat resistance and strength of the film. It should be noted that, for carrying out extensive research, it is preferable to use a simple method of mechanical mixing for components.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":" ","pages":""},"PeriodicalIF":0.3,"publicationDate":"2022-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43503704","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}
引用次数: 1
Synthesis, structure and mechanical properties of composite hydrogels for medical use 医用复合水凝胶的合成、结构和力学性能
IF 0.3
Chemical Bulletin of Kazakh National University Pub Date : 2022-03-13 DOI: 10.15328/cb1264
G. Mamytbekov, Zh.I. Beksultanov, V. Bannykh
{"title":"Synthesis, structure and mechanical properties of composite hydrogels for medical use","authors":"G. Mamytbekov, Zh.I. Beksultanov, V. Bannykh","doi":"10.15328/cb1264","DOIUrl":"https://doi.org/10.15328/cb1264","url":null,"abstract":"The mechanism of formation of slightly crosslinked composite hydrogels based on natural agar-agar polysaccharide, synthetic polymers for medical purposes – poly-N-vinylpyrrolidone (PVP) and low-molecular plasticizers (polyethylene glycol PEG-400 and glycerin) synthesized by electron irradiation was considered from the point of view of analyzing their mechanical characteristics under various types of applied efforts. It is established that the synthesis conditions and the component composition of the initial mixture determine the formed structure of the hydrogel compositions and their mechanical properties. A new interpretation of the formation of the structure of composite hydrogels in the presence of various plasticizers is given. A detailed analysis of the deformation curves of composite hydrogels is presented taking into account the elastic-elastic, highly elastic and forced-elastic states.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":" ","pages":""},"PeriodicalIF":0.3,"publicationDate":"2022-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49651745","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}
引用次数: 1
Stereocontrolled intramolecular transformations of (-)-α santonin (-)-αsantonin的立体控制分子内转化
IF 0.3
Chemical Bulletin of Kazakh National University Pub Date : 2022-01-21 DOI: 10.15328/cb1251
A. Iskanderov, P. Vojtisek, S. Zhokizhanova, Aktoty Jadenova, N. Merkhatuly
{"title":"Stereocontrolled intramolecular transformations of \u0000(-)-α santonin","authors":"A. Iskanderov, P. Vojtisek, S. Zhokizhanova, Aktoty Jadenova, N. Merkhatuly","doi":"10.15328/cb1251","DOIUrl":"https://doi.org/10.15328/cb1251","url":null,"abstract":"Chemical transformations of eudesmane sesquiterpene γ-lactones, leading to new biologically active compounds, have become an important direction in medicinal chemistry. This article discusses the stereoscopic intramolecular transformations of the sesquiterpene γ-lactone of the eudesmanic structure (-)-α santonin, a perspective natural compound characterized by a wide spectrum of biological activity.Stereoselective synthesis of new practically significant cis-condensed keto-eudesmane esters and ethylated santonin derivatives was carried out at room temperature in an argon atmosphere by the reaction of α-santonin with methyl and ethyl alcohols and alkyl halides in the presence of the Me3CONa-DMF base. It was revealed that, under the reaction conditions, the initial stage of santonin carbanion formation initiates subsequent stages of intramolecular electrophilic rearrangements with the formation of anenolate ion, which futhur interacts stereoselectively with nucleophilic and electrophilic reagents.It was shown that the synthesis of C4-α-ethyl-santonin with a six-membered ring configuration in the form of a distorted chair-chair can serve as a confirmation of the proposed mechanism of formation of practically valuable 6-keto-eudesmane ethers. In this article, the structure and spatial structure of the synthesized compounds is established using modern physicochemical and spectroscopic (1H NMR, 2D COZY NMR, NOESY, mass-spectrometry and X-ray structural analysis) research methods.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":" ","pages":""},"PeriodicalIF":0.3,"publicationDate":"2022-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48516601","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}
引用次数: 0
Synthesis of the S/AgBr nano/micropowder in DMSO-water system dmso -水体系中S/AgBr纳米/微粉的合成
IF 0.3
Chemical Bulletin of Kazakh National University Pub Date : 2022-01-21 DOI: 10.15328/cb1254
N. Khan
{"title":"Synthesis of the S/AgBr nano/micropowder in DMSO-water system","authors":"N. Khan","doi":"10.15328/cb1254","DOIUrl":"https://doi.org/10.15328/cb1254","url":null,"abstract":"A new synthesis method of S/AgBr nano/micropowder based on sulfur and silver halide was developed. The nano/micropowder was obtained in the DMSO-water system, in two stages. Initially, sulfur was dissolved in DMSO at 120°C. The resulting solution was cooled to room temperature and separated from sulfur by filtration. Then, pre-prepared water solutions of AgNO3 and NaBr were introduced drop by drop into a sulfur solution in DMSO, at room temperature. The phase composition and structure of the precipitated powdery sediment were studied by X-ray diffraction analysis (XRD) and Raman spectroscopy. Scanning electron microscopy (SEM) was used to study the morphology and particle size. XRD showed the presence of the crystalline phase of AgBr, while the Raman spectra were characterized by the presence of sulfur and AgBr peaks. The SEM results showed that the S/AgBr is represented by oval, spherical and triangular particles of a homogeneous structure; the particle size was in the range from 300 to 800 nm.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":" ","pages":""},"PeriodicalIF":0.3,"publicationDate":"2022-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43913288","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}
引用次数: 0
Thermoconversion of ethanol on Al2O3 and SiO2 oxides 乙醇在Al2O3和SiO2氧化物上的热转化
IF 0.3
Chemical Bulletin of Kazakh National University Pub Date : 2022-01-21 DOI: 10.15328/cb1227
M. Mambetova, Gaukhar Yergaziyevna, K. Dossumov
{"title":"Thermoconversion of ethanol on Al2O3 and SiO2 oxides","authors":"M. Mambetova, Gaukhar Yergaziyevna, K. Dossumov","doi":"10.15328/cb1227","DOIUrl":"https://doi.org/10.15328/cb1227","url":null,"abstract":"This work is devoted to the study of the catalytic properties of Al2O3 and SiO2 in the process of thermal conversion of ethanol, as well as to the determination of the acid characteristics of these oxides The catalytic properties of oxides in the thermal conversion of ethanol were studied in a flow-through mode at a reaction temperature of 250°C and a space velocity of 0,5 h-1. The acidic characteristics of the Al2O3 and SiO2 oxides were determined by the method temperature-programmed desorption of ammonia (TPD-NH3). \u0000It has been established that the process of thermal conversion of ethanol includes the reactions of dehydration, dehydrogenation and dimerization. During the thermal conversion of ethanol on aluminum and silicon oxides, a dehydration reaction occurs with the formation of diethyl ether, with concentrations of 24,5 vol. % on Al2O3 and 19,6 vol. % on SiO2. It was determined that in parallel with the reaction of ethanol dehydration, its dehydrogenation with the formation of acetaldehyde takes place, but with a lower selectivity compared to dehydration. It was found that on Al2O3, which has a lower acidity in comparison with SiO2, the deformation of acetaldehyde occurs with the formation of butanol.\u0000","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":" ","pages":""},"PeriodicalIF":0.3,"publicationDate":"2022-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43779595","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}
引用次数: 0
Synthesis and characterization of high molecular weight amphoteric terpolymer based on acrylamide, 2-acrylamido-2-methyl-1-propanesulfonic acid sodium salt and (3-acrylamidopropyl)trimethylammonium chloride for oil recovery 基于丙烯酰胺、2-丙烯酰胺-2-甲基-1-丙磺酸钠盐和(3-丙烯酰胺丙基)三甲基氯化铵的高分子量两性采油三元共聚物的合成与表征
IF 0.3
Chemical Bulletin of Kazakh National University Pub Date : 2021-11-06 DOI: 10.15328/cb1243
I. Gussenov, N. Mukhametgazy, A. Shakhvorostov, S. Kudaibergenov
{"title":"Synthesis and characterization of high molecular weight amphoteric terpolymer based on acrylamide, 2-acrylamido-2-methyl-1-propanesulfonic acid sodium salt and (3-acrylamidopropyl)trimethylammonium chloride for oil recovery","authors":"I. Gussenov, N. Mukhametgazy, A. Shakhvorostov, S. Kudaibergenov","doi":"10.15328/cb1243","DOIUrl":"https://doi.org/10.15328/cb1243","url":null,"abstract":"High molecular weight amphoteric terpolymer based on a nonionic monomer, acrylamide (AAm), an anionic monomer, 2-acrylamido-2-methyl-1-propanesulfonic acid sodium salt (AMPS), and a cationic monomer, (3-acrylamidopropyl) trimethylammonium chloride (APTAC), was prepared using free-radical copolymerization in an aqueous solution and characterized by 1H NMR, FTIR, GPC, DLS, zeta potential and viscometry. The polymer was shown to be viscosifying, and therefore can be utilized as a polymer flooding agent in the high salinity and temperature conditions of oil reservoirs. Injection of 0.25 wt.% of amphoteric terpolymer, dissolved in 200-300 g∙L-1 brine, into high and low permeability sand pack models demonstrated that the oil recovery factor (ORF) increases by up to 23-28% in comparison with saline water flooding. This is explained by an increase in the viscosity of brine solution due to disruption of intra- and interionic contacts between oppositely charged AMPS and APTAC moieties, demonstrating the antipolyelectrolyte effect. In high saline water, the anions and cations of salts screen the electrostatic attraction between positively and negatively charged macroions, resulting in expansion of the macromolecule. This phenomenon leads to an increase in the viscosifying effect on the brine solution, thus decreasing the mobility factor (M), which is defined as the ratio of displacing phase mobility (water) to displaced phase mobility (oil).","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":" ","pages":""},"PeriodicalIF":0.3,"publicationDate":"2021-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44598872","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}
引用次数: 5
Distribution of dissolved and suspended forms of heavy metals in the water of the Syr Darya, South Kazakhstan 哈萨克斯坦南部锡尔河水中溶解态和悬浮态重金属的分布
IF 0.3
Chemical Bulletin of Kazakh National University Pub Date : 2021-10-22 DOI: 10.15328/cb1016
B. Uralbekov, B. Satybaldiyev, D. Snow
{"title":"Distribution of dissolved and suspended forms of heavy metals in the water of the Syr Darya, South Kazakhstan","authors":"B. Uralbekov, B. Satybaldiyev, D. Snow","doi":"10.15328/cb1016","DOIUrl":"https://doi.org/10.15328/cb1016","url":null,"abstract":"The water of the Syr Darya is the main source of fresh water in South Kazakhstan and heavily used for agriculture. The use water from the Syr Darya for irrigation of agricultural fields affects its chemical composition and is reflected in the water quality class provided in the bulletins of the Ministry of Ecology, Geology and Natural Resources of the Republic of Kazakhstan. In the present work, the distribution of suspended and dissolved forms of heavy metals in the water of the Syr Darya has been studied in two areas – the upper reaches of the river from the Shardara reservoir to the «Koksaray» bridge and the lower reaches of the river from Turkestan to Terenozek. Concentrations of heavy metals and metalloids were determined by inductively coupled plasma mass spectrometry (ICP-MS, Agilent 7500A, United States) and compared to these recommended levels. Total concentrations of several metals (V, Cu, Mn, Fe, Sr) exceed the Maximum Permissible Concentrations established for waters of fishery reservoirs. The role of the suspended form in the geochemical migration of a number of metals in the water of the Syr Darya River is estimated and it was shown that this form is a significant fraction of the total metal concentration. The distribution of suspended forms of metals correlates to the turbidity of the water of the Syr Darya.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":" ","pages":""},"PeriodicalIF":0.3,"publicationDate":"2021-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47718608","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}
引用次数: 0
Synthesis of nanocomposite material through modification of graphene oxide by nanocellulose 用纳米纤维素改性氧化石墨烯制备纳米复合材料
IF 0.3
Chemical Bulletin of Kazakh National University Pub Date : 2021-09-22 DOI: 10.15328/cb1238
K. Akatan, T. Kuanyshbekov, S. Kabdrakhmanova, Aidana Imasheva, A. Battalova, R. Abylkalykova, A. Nasyrova, Zhanar Ibraeva
{"title":"Synthesis of nanocomposite material through modification of graphene oxide by nanocellulose","authors":"K. Akatan, T. Kuanyshbekov, S. Kabdrakhmanova, Aidana Imasheva, A. Battalova, R. Abylkalykova, A. Nasyrova, Zhanar Ibraeva","doi":"10.15328/cb1238","DOIUrl":"https://doi.org/10.15328/cb1238","url":null,"abstract":"Intensive research of nanocomposites contributes to the development of new materials in the fields of medicine, nanoelectronics, energy, biotechnology, information technology. Therefore, the synthesis of new materials by modifying of graphene oxide (GO) with nanocellulose and the study of its properties are of great interest. In this study synthesized nanocomposite material by modifying of graphene oxide (GO) from activated carbon (BAU-A) in a 1:1 volume ratio with nanocellulose (NC) from hemp stems belonging to the annual plant, and their chemical structure was studied by FTIR and UV-spectroscopy. The results of the study showed the absorption of the etheric bond C = O in the UV spectrum at full length 243 nm. The IR spectrum showed all the new etheric bonds O = C - OH at a wavelength of 1625 cm-1. The average particle sizes of GO was 352 nm and NC was 470 nm in length and 80 nm in width. The SEM analysis indicating the NC as a contact layer between ultralow thicknesses of the GO layers. The XRD analysis indicated GO-NC composite film is a substance comprising GO and NC. According to the results, modification of graphene oxide showed that its scope can be expanded as much as possible.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":" ","pages":""},"PeriodicalIF":0.3,"publicationDate":"2021-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44818568","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}
引用次数: 3
Powder bismuth-based anode material for magnesium-ion batteries and its properties 镁离子电池用粉末铋基负极材料及其性能
IF 0.3
Chemical Bulletin of Kazakh National University Pub Date : 2021-09-22 DOI: 10.15328/cb1221
A. Abildina, R. Dzhumanova, G. Rakhymbay, A. Beiseyeva, A. Argimbayeva
{"title":"Powder bismuth-based anode material for magnesium-ion batteries and its properties","authors":"A. Abildina, R. Dzhumanova, G. Rakhymbay, A. Beiseyeva, A. Argimbayeva","doi":"10.15328/cb1221","DOIUrl":"https://doi.org/10.15328/cb1221","url":null,"abstract":"In this work an intercalation anode material synthesized on the base of the powdered bismuth is presented. The uniformly distribution of carbon paste suspension over the substrate surface was found out by scanning-electron microscopy. The regularities of electrochemical intercalation and deintercalation of magnesium ions into the electrode created on the base of powdered bismuth in a solution of 0.25 mol/L Mg(N(SO2CF3)2)2 on the base of acetonitrile were studied. The cyclic voltammograms with the results of scanning electron microscopy and atomic emission analysis indicate that in the cathode area the reduction processes proceed with the formation of an intermetallic compound – MgxBiy; two peaks were observed at the reverse course which were conceivably corresponding to two-stage magnesium oxidation. According to cyclic voltammograms by the difference in the potential of peaks in the forward and reverse directions it was established that the processes of reduction and oxidation of magnesium ions into intercalation material were irreversible. The diffusion coefficients of intercalation and deintercalation into the electrode material were calculated using the Rendles-Shevchik equation; they were 3.12·10-11 sm2/s and 1.85·10-11 sm2/s, respectively. X-ray diffraction (XRD) results demonstrated the cubic structure of the bismuth crystal lattice with altered parameters corresponding to inter-metallide formation. At galvanostatic cycling of the synthesized anode material a capacity of up to 104 mA·h·g-1 at current load 1C was achieved. Such results can be a good indicator for the development of magnesium-ion power sources.","PeriodicalId":9860,"journal":{"name":"Chemical Bulletin of Kazakh National University","volume":" ","pages":""},"PeriodicalIF":0.3,"publicationDate":"2021-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45957470","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}
引用次数: 0
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