Pub Date : 2021-01-01DOI: 10.32737/2221-8688-2021-1-32-36
G. Talybov, S. A. Musaeva
Alkoxyiodination of 1-vinyl-4-organylbenzenes with 2-methyl-3-buten-1-ol and crystalline iodine in the presence of clinoptilolite (NaK) 4CaAl6Ci30O72 leads to allyl b-iodoethers in high yields which in the presence of heteropolyacids are converted into substituted 1,4 -dioxane.
{"title":"HETEROCYCLIZATION OF ALLYL - IODOETHERS IN 1,4-DIOXANE DERIVATIVES","authors":"G. Talybov, S. A. Musaeva","doi":"10.32737/2221-8688-2021-1-32-36","DOIUrl":"https://doi.org/10.32737/2221-8688-2021-1-32-36","url":null,"abstract":"Alkoxyiodination of 1-vinyl-4-organylbenzenes with 2-methyl-3-buten-1-ol and crystalline iodine in the presence of clinoptilolite (NaK) 4CaAl6Ci30O72 leads to allyl b-iodoethers in high yields which in the presence of heteropolyacids are converted into substituted 1,4 -dioxane.","PeriodicalId":10015,"journal":{"name":"Chemical Problems","volume":"214 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74760360","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}
Pub Date : 2021-01-01DOI: 10.32737/2221-8688-2021-4-232-240
K. Allahverdiyeva
The influence of the graphite concentration on the main physical-mechanical properties of nanocomposites based on such polyolefin as high density polyethylene, low density polyethylene and polypropylene is considered. Properties such as tensile yield stress, ultimate tensile stress, and ultimate bending strength, elongation at break, heat resistance, flexural strength, MFI, and melting points are analysed. To improve the compatibility of the mixed components of the mixture, we used an Exxelor PO1040 compatibilizer for all grades of polyethylene and Exxelor PO1020 for polypropylene. Graphite was introduced into the composition of polyolefin at the following concentrations: 1.0, 3.0, 5.0, 10, 15, 20, and 30 wt%. As a result of the research, it was found that the introduction of graphite into the composition of polyolefin was accompanied by an improvement in strength characteristics with maximum at various concentrations. For high density polyethylene, the maximum values of strength characteristics are observed at 3.0 wt%, for low density polyethylene at 10 wt%, and for polypropylene at 5.0 wt% content of graphite. It revealed that such a difference in the value of the threshold concentration of graphite which provides the maximum value of strength indicators,was directly related to the degree of crystallinity of the polymer matrix.
{"title":"PHYSICAL-MECHANICAL PROPERTIES OF NANOCOMPOSITES BASED ON GRAPHITE AND MODIFIED POLYOLEFINS","authors":"K. Allahverdiyeva","doi":"10.32737/2221-8688-2021-4-232-240","DOIUrl":"https://doi.org/10.32737/2221-8688-2021-4-232-240","url":null,"abstract":"The influence of the graphite concentration on the main physical-mechanical properties of nanocomposites based on such polyolefin as high density polyethylene, low density polyethylene and polypropylene is considered. Properties such as tensile yield stress, ultimate tensile stress, and ultimate bending strength, elongation at break, heat resistance, flexural strength, MFI, and melting points are analysed. To improve the compatibility of the mixed components of the mixture, we used an Exxelor PO1040 compatibilizer for all grades of polyethylene and Exxelor PO1020 for polypropylene. Graphite was introduced into the composition of polyolefin at the following concentrations: 1.0, 3.0, 5.0, 10, 15, 20, and 30 wt%. As a result of the research, it was found that the introduction of graphite into the composition of polyolefin was accompanied by an improvement in strength characteristics with maximum at various concentrations. For high density polyethylene, the maximum values of strength characteristics are observed at 3.0 wt%, for low density polyethylene at 10 wt%, and for polypropylene at 5.0 wt% content of graphite. It revealed that such a difference in the value of the threshold concentration of graphite which provides the maximum value of strength indicators,was directly related to the degree of crystallinity of the polymer matrix.","PeriodicalId":10015,"journal":{"name":"Chemical Problems","volume":"354 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76481136","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}
Pub Date : 2021-01-01DOI: 10.32737/2221-8688-2021-4-256-261
S. Zargarova
Oligomeric surfactant based on octadecylamine and propylene oxide was synthesized. The degrees of oligomerization of octadecylamine was calculated as 6.2 Structure and composition of the surfactant was confirmed by using IR and UV-spectroscopy. Surface tension values with respect to concentration were examined and respective curve was plotted. Also, main surf activity parameters like CMC, CMC, πCMC, C20, pC20, Γmax, Amin were calculated. Critical micelle concentrations (CMC) and surface tensions at CMC were calculated as 1.58*10-4 mol/l and 31.92 mN/m respectively. Petrocollecting property and petrocollecting coefficients of the surfactant were studied for distilled, tap and sea water.
{"title":"OBTAINING AND STUDY OF OLIGOMERIC SURFACTANT BASED ON OCTADECYLAMINE AND OXYPROPYLENE","authors":"S. Zargarova","doi":"10.32737/2221-8688-2021-4-256-261","DOIUrl":"https://doi.org/10.32737/2221-8688-2021-4-256-261","url":null,"abstract":"Oligomeric surfactant based on octadecylamine and propylene oxide was synthesized. The degrees of oligomerization of octadecylamine was calculated as 6.2 Structure and composition of the surfactant was confirmed by using IR and UV-spectroscopy. Surface tension values with respect to concentration were examined and respective curve was plotted. Also, main surf activity parameters like CMC, CMC, πCMC, C20, pC20, Γmax, Amin were calculated. Critical micelle concentrations (CMC) and surface tensions at CMC were calculated as 1.58*10-4 mol/l and 31.92 mN/m respectively. Petrocollecting property and petrocollecting coefficients of the surfactant were studied for distilled, tap and sea water.","PeriodicalId":10015,"journal":{"name":"Chemical Problems","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82168219","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}
Pub Date : 2021-01-01DOI: 10.32737/2221-8688-2021-3-143-149
Y. B. Ramazanova
The purpose of the research was to study rheological properties of Azerbaijani oils from the Sangachali and Muradkhanli fields. In order to improve rheological properties of the oil produced from the Muradkhanli and Sangachali fields, a Russian-made depressant СНПХ -2005 additive was used. To determine the optimal concentration of the СНПХ-2005 and confirm its positive effect on oil and oil products, control samples were prepared with this additive in oil M-8 and the oil from the above fields with the calculation of 0.5 kg/t, 0.8 kg/t and 1.0 kg/t. In parallel, similar samples were prepared with the depressant АзНИИ. The pour points of the samples were investigated at -5 0С, -100С and -200С on the rotational viscometer REOTECT-2. It found that the sample with the СНПХ -2005 additive (at the concentration of 0.8%) in the M-8 oil has a lower pour point (minus 40°C) as compared to a similar sample with the depressant АзНИИ (-32°C). The sample with the depressant СНПХ-2005 (at the concentration of 0.8%) and oil reveals the best rheological properties (minus 38°C versus -30°C). As a result of the studies carried out, it was determined that the introduction of the depressant СНПХ-2005 improves rheological parameters of the oil from the above fields, and thereby makes it possible to refuse additional heating in low temperature areas when pumping oil through the oil pipeline.
{"title":"DEPRESSOR ADDITIVE FOR OIL PUMPING","authors":"Y. B. Ramazanova","doi":"10.32737/2221-8688-2021-3-143-149","DOIUrl":"https://doi.org/10.32737/2221-8688-2021-3-143-149","url":null,"abstract":"The purpose of the research was to study rheological properties of Azerbaijani oils from the Sangachali and Muradkhanli fields. In order to improve rheological properties of the oil produced from the Muradkhanli and Sangachali fields, a Russian-made depressant СНПХ -2005 additive was used. To determine the optimal concentration of the СНПХ-2005 and confirm its positive effect on oil and oil products, control samples were prepared with this additive in oil M-8 and the oil from the above fields with the calculation of 0.5 kg/t, 0.8 kg/t and 1.0 kg/t. In parallel, similar samples were prepared with the depressant АзНИИ. The pour points of the samples were investigated at -5 0С, -100С and -200С on the rotational viscometer REOTECT-2. It found that the sample with the СНПХ -2005 additive (at the concentration of 0.8%) in the M-8 oil has a lower pour point (minus 40°C) as compared to a similar sample with the depressant АзНИИ (-32°C). The sample with the depressant СНПХ-2005 (at the concentration of 0.8%) and oil reveals the best rheological properties (minus 38°C versus -30°C). As a result of the studies carried out, it was determined that the introduction of the depressant СНПХ-2005 improves rheological parameters of the oil from the above fields, and thereby makes it possible to refuse additional heating in low temperature areas when pumping oil through the oil pipeline.","PeriodicalId":10015,"journal":{"name":"Chemical Problems","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83383803","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}
Pub Date : 2021-01-01DOI: 10.32737/2221-8688-2021-2-107-112
M. S. Pirguliyeva, A. Guliyev
The adducts were synthesized by means of diene condensation reaction of levopimaric acid with acrylic acid, and through carrying out the free radical addition of ethandithiol to levopimaric acid. The composition and structure of these adducts were identified through data of the elemental analysis, IR and PMR spectroscopy. The efficiency of the synthesized diacids as corrosion inhibitors was determined by means of the gravimetric method (on mass losses of a sample of steel plate of mark C-3) in an acidic medium (solutions of 1H and 5H of sulfuric acid). The influence of the medium temperature and concentration of the used compounds on the degree of protection and corrosion inhibition coefficient was analyzed. It found that rise in temperature results in the increase of protective effect of the inhibitor. Note that the increase of the inhibitor concentration, raising the degree of protection though, is not so noticeable.
{"title":"ADDUCTS OF LEVOPIMARIC ACID WITH ACRYLIC ACID AND ETHANEDITHIOL AS ACID CORROSION INHIBITORS OF METALS","authors":"M. S. Pirguliyeva, A. Guliyev","doi":"10.32737/2221-8688-2021-2-107-112","DOIUrl":"https://doi.org/10.32737/2221-8688-2021-2-107-112","url":null,"abstract":"The adducts were synthesized by means of diene condensation reaction of levopimaric acid with acrylic acid, and through carrying out the free radical addition of ethandithiol to levopimaric acid. The composition and structure of these adducts were identified through data of the elemental analysis, IR and PMR spectroscopy. The efficiency of the synthesized diacids as corrosion inhibitors was determined by means of the gravimetric method (on mass losses of a sample of steel plate of mark C-3) in an acidic medium (solutions of 1H and 5H of sulfuric acid). The influence of the medium temperature and concentration of the used compounds on the degree of protection and corrosion inhibition coefficient was analyzed. It found that rise in temperature results in the increase of protective effect of the inhibitor. Note that the increase of the inhibitor concentration, raising the degree of protection though, is not so noticeable.","PeriodicalId":10015,"journal":{"name":"Chemical Problems","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78026297","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}
Pub Date : 2021-01-01DOI: 10.32737/2221-8688-2021-2-101-106
A. Aliyev, G. A. Ali-zade, M.Q. Aliyeva, A. Safarov, V. M. Yariyev, R.A. Ahmedov
The article studied and compared the reactivity of cyclohexanol and methylcyclohexanol isomers in the oxidative dehydrogenation reaction over modified zeolite catalysts. It found that rates of oxidative dehydrogenation of all methylcyclohexanol isomers are practically the same and exceed rates of oxidative dehydrogenation of cyclohexanol into cyclohexanone.
{"title":"RESEARCH INTO REACTION ABILITY OF CYCLOHEXANOL AND METHYLCYCLOHEXANOLS IN THE OXIDATIVE DEHYDRATION REACTION OVER MODIFIED ZEOLITE CATALYSTS","authors":"A. Aliyev, G. A. Ali-zade, M.Q. Aliyeva, A. Safarov, V. M. Yariyev, R.A. Ahmedov","doi":"10.32737/2221-8688-2021-2-101-106","DOIUrl":"https://doi.org/10.32737/2221-8688-2021-2-101-106","url":null,"abstract":"The article studied and compared the reactivity of cyclohexanol and methylcyclohexanol isomers in the oxidative dehydrogenation reaction over modified zeolite catalysts. It found that rates of oxidative dehydrogenation of all methylcyclohexanol isomers are practically the same and exceed rates of oxidative dehydrogenation of cyclohexanol into cyclohexanone.","PeriodicalId":10015,"journal":{"name":"Chemical Problems","volume":"70 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74471959","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}
Pub Date : 2021-01-01DOI: 10.32737/2221-8688-2021-3-168-172
O.M. Aliyev, T. F. Maksudova, D.S. Azhdarova, S. Mamedov, Sh.A. Gamidova
The phase equilibrium in the Bi2S3 – YbS system was studied by the methods of physicochemical analysis – DTA, XRD, MSA through measuring the micro-hardness and density, and a state diagram was plotted. It has been found that this system is a quasi-binary cross-section of the Yb-Bi-S ternary system. The formation of the two ternary compounds with YbBi2S4 and YbBi4S7 compositions was detected and the areas of solid solutions determined.
{"title":"THE Bi2S3 – YbS SYSTEM","authors":"O.M. Aliyev, T. F. Maksudova, D.S. Azhdarova, S. Mamedov, Sh.A. Gamidova","doi":"10.32737/2221-8688-2021-3-168-172","DOIUrl":"https://doi.org/10.32737/2221-8688-2021-3-168-172","url":null,"abstract":"The phase equilibrium in the Bi2S3 – YbS system was studied by the methods of physicochemical analysis – DTA, XRD, MSA through measuring the micro-hardness and density, and a state diagram was plotted. It has been found that this system is a quasi-binary cross-section of the Yb-Bi-S ternary system. The formation of the two ternary compounds with YbBi2S4 and YbBi4S7 compositions was detected and the areas of solid solutions determined.","PeriodicalId":10015,"journal":{"name":"Chemical Problems","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87563462","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}
Pub Date : 2021-01-01DOI: 10.32737/2221-8688-2021-3-179-185
V.A. Guseinova, G.A. Zaidova, E.I. Mammadov
The reactions of electrophilic addition of cycloalkane carboxylic acid chlorides with allyl chlorides were studied. It was found, that depending on the chloride structures, 2- and 2,4-substituted furans, 1-R-3,4- dichloro-2-butene-1-ones and 1-R-3,4,4-trichloro-1-butanones were obtained.
研究了环烷羧酸氯化物与烯丙基氯化物的亲电加成反应。结果表明，根据氯结构的不同，可以得到2-呋喃和2,4-取代呋喃、1- r -3,4-二氯-2-丁烯-1和1- r -3,4,4-三氯-1-丁酮。
{"title":"REACTION OF CHLOROANHYDRIDES OF CYCLOALKANECARBOXILIC ACIDS WITH SOME ALLYLIC CHLORIDES","authors":"V.A. Guseinova, G.A. Zaidova, E.I. Mammadov","doi":"10.32737/2221-8688-2021-3-179-185","DOIUrl":"https://doi.org/10.32737/2221-8688-2021-3-179-185","url":null,"abstract":"The reactions of electrophilic addition of cycloalkane carboxylic acid chlorides with allyl chlorides were studied. It was found, that depending on the chloride structures, 2- and 2,4-substituted furans, 1-R-3,4- dichloro-2-butene-1-ones and 1-R-3,4,4-trichloro-1-butanones were obtained.","PeriodicalId":10015,"journal":{"name":"Chemical Problems","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83372626","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}
Pub Date : 2021-01-01DOI: 10.32737/2221-8688-2021-4-215-223
S. Mammadova, Ch.M. Seyidova, C. Guliyeva, A.R. Racabli, H. Aslanova, N.T. Shikhverdiyeva, N. Rahimli, N. Zeynalov
Network polymer hydrogels with high swelling effect were synthesized by using of ultraviolet crosslinking, with crosslinking agent N,N'-methylene-bis-acrylamide with chitosan an average molecular weight of 100-300 kDa t. The amount of crosslinking agent made up 10% of chitosan weight. The gel structure was studied using FTIR and the mechanism of the cross-linking process identified. The sorption of levofloxacin on the obtained hydrogel was studied at different pH and the degree of sorption and the dependence of the sorption capacity of the hydrogel on the pH of the medium was studied. It found that the degree of sorption of hydrogel by levofloxacin is 90.4 % while the sorption capacity of gel increases as pH of the medium rises and at pH=8 it has the highest value equal to 8.9 mg/g.
{"title":"OBTAINING A HYDROGEL BASED ON CHITOSAN, STUDY ITS STRUCTURE AND SORBTION ABILITY WITH LEVOFLOXACIN ANTIBIOTICS","authors":"S. Mammadova, Ch.M. Seyidova, C. Guliyeva, A.R. Racabli, H. Aslanova, N.T. Shikhverdiyeva, N. Rahimli, N. Zeynalov","doi":"10.32737/2221-8688-2021-4-215-223","DOIUrl":"https://doi.org/10.32737/2221-8688-2021-4-215-223","url":null,"abstract":"Network polymer hydrogels with high swelling effect were synthesized by using of ultraviolet crosslinking, with crosslinking agent N,N'-methylene-bis-acrylamide with chitosan an average molecular weight of 100-300 kDa t. The amount of crosslinking agent made up 10% of chitosan weight. The gel structure was studied using FTIR and the mechanism of the cross-linking process identified. The sorption of levofloxacin on the obtained hydrogel was studied at different pH and the degree of sorption and the dependence of the sorption capacity of the hydrogel on the pH of the medium was studied. It found that the degree of sorption of hydrogel by levofloxacin is 90.4 % while the sorption capacity of gel increases as pH of the medium rises and at pH=8 it has the highest value equal to 8.9 mg/g.","PeriodicalId":10015,"journal":{"name":"Chemical Problems","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80391828","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}
Pub Date : 2021-01-01DOI: 10.32737/2221-8688-2021-1-41-46
A. Karimov
Kinetic regularities of the oxidative dehydrogenation reaction of methylcyclohexane on the -clinoptilolite catalyst were investigated. Absence of internal and external diffusion inhibition was established, the reaction proceeds in the kinetic area, in which all diffusion stages proceed much faster than all chemical stages that make up the mechanism of this reaction. The influence of partial pressures of reagents, the reaction temperature and the space velocity of the reaction mixture on the course of the reaction was studied and optimal conditions for obtaining the intentional reaction product determined.
{"title":"RESEARCH INTO KINETIC REGULARITIES OF THE REACTION OF OXIDATIVE DEHYDROGENATION OF METHYLCYCLOHEXANE OVER MODIFIED ZEOLITES","authors":"A. Karimov","doi":"10.32737/2221-8688-2021-1-41-46","DOIUrl":"https://doi.org/10.32737/2221-8688-2021-1-41-46","url":null,"abstract":"Kinetic regularities of the oxidative dehydrogenation reaction of methylcyclohexane on the -clinoptilolite catalyst were investigated. Absence of internal and external diffusion inhibition was established, the reaction proceeds in the kinetic area, in which all diffusion stages proceed much faster than all chemical stages that make up the mechanism of this reaction. The influence of partial pressures of reagents, the reaction temperature and the space velocity of the reaction mixture on the course of the reaction was studied and optimal conditions for obtaining the intentional reaction product determined.","PeriodicalId":10015,"journal":{"name":"Chemical Problems","volume":"62 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85848060","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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