Pub Date : 2023-09-30DOI: 10.5155/eurjchem.14.3.311-315.2463
Rita Ruivo, Luis Alves, Ana Martins
New Ti(III) and Mo(III) complexes of formulae [(PNP-Ph)TiCl3], 1, and [(PNP-iPr)MoCl3], 2, where PNP-Ph = N,N’-bis(diphenylphosphino)-2,6-diaminopyridine and PNP-iPr = N,N’-bis(diisopropylphosphino)-2,6-diaminopyridine were synthesised, in moderate yields, by reaction of MCl3·(THF)3 (M = Ti and Mo) with the suitable ligand precursor. The solid-state molecular structures of complexes 1 and 2 were obtained by single-crystal X-ray diffraction. Crystal data for C37H41Cl3N3O2P2Ti (1·(C4H8O)2): triclinic, space group P-1 (no. 2), a = 10.0945(4) Å, b = 10.3002(4) Å, c = 18.6233(7) Å, α = 92.412(2)°, β = 91.108(2)°, γ = 101.705(3)°, V = 1893.65(13) Å3, Z = 2, µ(MoKα) = 0.559 mm-1, Dcalc = 1.361 g.cm-3, 20760 reflections measured (2.021 ≤ Θ ≤ 27.130), 8327 unique (Rint = 0.0399, Rsigma = 0.0414) which were used in all calculations. The final R1 was 0.0316 (I > σ(I)) and wR2 was 0.0850 (all data). Crystal data for C17H33Cl3MoN3P2 (2): tetragonal, space group I41/a (no. 88), a = b = 19.468(4) Å, c = 31.711(6) Å, α = β = γ = 90°, V = 12019(5) Å3, Z = 16, µ(MoKα) = 0.816 mm-1, Dcalc = 1.202 g.cm-3, 42367 reflections measured (2.569 ≤ Θ ≤ 25.347), 5498 unique (Rint = 0.1408, Rsigma = 0.1293) which were used in all calculations. The final R1 was 0.1005 (I > σ(I)) and wR2 was 0.3194 (all data). The coordination geometry around the titanium and molybdenum centers is best described as octahedral, with three donor atoms of the PNP ligand and one chlorine atom occupying the equatorial plane. The axial positions of the octahedron are occupied by the other two chlorido ligands in both complexes. The NH spacer groups in the PNP ligands have an important role in the establishment of hydrogen bonds between the complexes and molecules of the solvent or neighbouring species.
{"title":"Synthesis and structural characterization of Ti(III) and Mo(III) complexes supported by PNP pincer ligands","authors":"Rita Ruivo, Luis Alves, Ana Martins","doi":"10.5155/eurjchem.14.3.311-315.2463","DOIUrl":"https://doi.org/10.5155/eurjchem.14.3.311-315.2463","url":null,"abstract":"New Ti(III) and Mo(III) complexes of formulae [(PNP-Ph)TiCl3], 1, and [(PNP-iPr)MoCl3], 2, where PNP-Ph = N,N’-bis(diphenylphosphino)-2,6-diaminopyridine and PNP-iPr = N,N’-bis(diisopropylphosphino)-2,6-diaminopyridine were synthesised, in moderate yields, by reaction of MCl3·(THF)3 (M = Ti and Mo) with the suitable ligand precursor. The solid-state molecular structures of complexes 1 and 2 were obtained by single-crystal X-ray diffraction. Crystal data for C37H41Cl3N3O2P2Ti (1·(C4H8O)2): triclinic, space group P-1 (no. 2), a = 10.0945(4) Å, b = 10.3002(4) Å, c = 18.6233(7) Å, α = 92.412(2)°, β = 91.108(2)°, γ = 101.705(3)°, V = 1893.65(13) Å3, Z = 2, µ(MoKα) = 0.559 mm-1, Dcalc = 1.361 g.cm-3, 20760 reflections measured (2.021 ≤ Θ ≤ 27.130), 8327 unique (Rint = 0.0399, Rsigma = 0.0414) which were used in all calculations. The final R1 was 0.0316 (I > σ(I)) and wR2 was 0.0850 (all data). Crystal data for C17H33Cl3MoN3P2 (2): tetragonal, space group I41/a (no. 88), a = b = 19.468(4) Å, c = 31.711(6) Å, α = β = γ = 90°, V = 12019(5) Å3, Z = 16, µ(MoKα) = 0.816 mm-1, Dcalc = 1.202 g.cm-3, 42367 reflections measured (2.569 ≤ Θ ≤ 25.347), 5498 unique (Rint = 0.1408, Rsigma = 0.1293) which were used in all calculations. The final R1 was 0.1005 (I > σ(I)) and wR2 was 0.3194 (all data). The coordination geometry around the titanium and molybdenum centers is best described as octahedral, with three donor atoms of the PNP ligand and one chlorine atom occupying the equatorial plane. The axial positions of the octahedron are occupied by the other two chlorido ligands in both complexes. The NH spacer groups in the PNP ligands have an important role in the establishment of hydrogen bonds between the complexes and molecules of the solvent or neighbouring species.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136336952","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 : 2023-09-30DOI: 10.5155/eurjchem.14.3.316-322.2436
Ravi Ranjan, Durga Gupta, Madhulata Shukla
Ionic liquids (ILs) carrying special properties can act as electronic as well as steric stabilisers by preventing nanoparticle (NP) growth and NP aggregation. The effect of visible light on the catalytic properties of silver nanoparticles is a hot topic of extensive research nowadays. The present report demonstrates the current developments in the green synthesis of silver nanoparticles in ionic liquids and a detailed study of the room-temperature catalytic and photocatalytic reduction of p-nitrophenol (PNP) to p-aminophenol (AP). The Ag nanoparticles (AgNPs) functionalised by ionic liquids are prepared in the 40-140 nm range and are found to be spherical in shape. The photocatalytic properties of these nanocomposites for the reduction of PNP to AP were studied. Photocatalytic degradation of PNP was also analysed by these composite nanostructures. The plasmonic photocatalytic properties of the synthesised AgNPs revealed activity significantly higher than that of the room-temperature catalysis. Density functional theory calculations showed that strong interactions exist between nanoclusters and ILs. Natural bond orbital analysis showed that IL also activates the nanoparticles for further photocatalytic reduction by transferring electron transfer from the donor (IL) to the acceptor (Ag cluster) and activating the silver NPs for further catalytic reaction. Photocatalytic degradation of PNP (reduction of PNP to AP) using NP in the absence of light follows first-order kinetics, whereas in the presence of light it follows zero-order reaction kinetics.
{"title":"Green synthesis of silver nano-catalyst using ionic liquid and their photocatalytic application to the reduction of p-nitrophenol","authors":"Ravi Ranjan, Durga Gupta, Madhulata Shukla","doi":"10.5155/eurjchem.14.3.316-322.2436","DOIUrl":"https://doi.org/10.5155/eurjchem.14.3.316-322.2436","url":null,"abstract":"Ionic liquids (ILs) carrying special properties can act as electronic as well as steric stabilisers by preventing nanoparticle (NP) growth and NP aggregation. The effect of visible light on the catalytic properties of silver nanoparticles is a hot topic of extensive research nowadays. The present report demonstrates the current developments in the green synthesis of silver nanoparticles in ionic liquids and a detailed study of the room-temperature catalytic and photocatalytic reduction of p-nitrophenol (PNP) to p-aminophenol (AP). The Ag nanoparticles (AgNPs) functionalised by ionic liquids are prepared in the 40-140 nm range and are found to be spherical in shape. The photocatalytic properties of these nanocomposites for the reduction of PNP to AP were studied. Photocatalytic degradation of PNP was also analysed by these composite nanostructures. The plasmonic photocatalytic properties of the synthesised AgNPs revealed activity significantly higher than that of the room-temperature catalysis. Density functional theory calculations showed that strong interactions exist between nanoclusters and ILs. Natural bond orbital analysis showed that IL also activates the nanoparticles for further photocatalytic reduction by transferring electron transfer from the donor (IL) to the acceptor (Ag cluster) and activating the silver NPs for further catalytic reaction. Photocatalytic degradation of PNP (reduction of PNP to AP) using NP in the absence of light follows first-order kinetics, whereas in the presence of light it follows zero-order reaction kinetics.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136336309","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 : 2023-09-30DOI: 10.5155/eurjchem.14.3.353-361.2443
Aphouet Aurelie Koffi, N'guadi Blaise Allou, Mougo Andre Tigori, Teminfolo Yaya Soro, Albert Trokourey, Paulin Marius Niamien
This work deals with aluminium corrosion inhibition by expired drugs containing flucloxacillin in 1 M hydrochloric acid medium, using the gravimetric method and density functional theory. Weight loss results showed that the inhibitory efficiency of this compound increases with concentration and decreases with increasing temperature. The study also indicates that this molecule is adsorbed according to the modified Langmuir model (Villamil model). Furthermore, the thermodynamic parameters of adsorption (∆Goads, ∆Hoads, ∆Soads) and activation (Ea*, ΔHa*, ΔSa*) show that the adsorption is mixed type (chemisorption and physisorption). In addition, density functional theory provides access to the quantum chemical parameters of the molecule such as the lowest vacant orbital energy (ELUMO), the highest occupied orbital energy (EHOMO), the absolute electronegativity (χ), the global hardness (η), the global softness (S), the fraction of transferred electrons (ΔN) as well as the electrophilicity index (ω) for finding correlation between the inhibitor structure and the experimental data.
{"title":"Study of expired Fuclo 500 drug as an environmentally sustainable corrosion inhibitor","authors":"Aphouet Aurelie Koffi, N'guadi Blaise Allou, Mougo Andre Tigori, Teminfolo Yaya Soro, Albert Trokourey, Paulin Marius Niamien","doi":"10.5155/eurjchem.14.3.353-361.2443","DOIUrl":"https://doi.org/10.5155/eurjchem.14.3.353-361.2443","url":null,"abstract":"This work deals with aluminium corrosion inhibition by expired drugs containing flucloxacillin in 1 M hydrochloric acid medium, using the gravimetric method and density functional theory. Weight loss results showed that the inhibitory efficiency of this compound increases with concentration and decreases with increasing temperature. The study also indicates that this molecule is adsorbed according to the modified Langmuir model (Villamil model). Furthermore, the thermodynamic parameters of adsorption (∆Goads, ∆Hoads, ∆Soads) and activation (Ea*, ΔHa*, ΔSa*) show that the adsorption is mixed type (chemisorption and physisorption). In addition, density functional theory provides access to the quantum chemical parameters of the molecule such as the lowest vacant orbital energy (ELUMO), the highest occupied orbital energy (EHOMO), the absolute electronegativity (χ), the global hardness (η), the global softness (S), the fraction of transferred electrons (ΔN) as well as the electrophilicity index (ω) for finding correlation between the inhibitor structure and the experimental data.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136336656","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 : 2023-09-30DOI: 10.5155/eurjchem.14.3.393-400.2442
Gabriel Vitor de Lima Marques, Renata Barbosa de Oliveira
From the Himalayan mountains to the South American coast, Cannabis, a general term for plants of the genus Cannabis, with thousands of years of contact with humankind, shows its versatility as food tools such as hemp, religious and hedonistic input, and other purposes through the millennia, according to the populations in question. In this paper, a review of the context of the use of Cannabis and its place in world history is presented, from ancient Mesopotamian relics, traditional Chinese and Ayurvedic medicines, to the reasoning behind the isolation and structural elucidation of three phytocannabinoids and the spread of Cannabis throughout the world.
{"title":"From ancient Asian relics to contemporaneity: A review of historical and chemical aspects of Cannabis","authors":"Gabriel Vitor de Lima Marques, Renata Barbosa de Oliveira","doi":"10.5155/eurjchem.14.3.393-400.2442","DOIUrl":"https://doi.org/10.5155/eurjchem.14.3.393-400.2442","url":null,"abstract":"From the Himalayan mountains to the South American coast, Cannabis, a general term for plants of the genus Cannabis, with thousands of years of contact with humankind, shows its versatility as food tools such as hemp, religious and hedonistic input, and other purposes through the millennia, according to the populations in question. In this paper, a review of the context of the use of Cannabis and its place in world history is presented, from ancient Mesopotamian relics, traditional Chinese and Ayurvedic medicines, to the reasoning behind the isolation and structural elucidation of three phytocannabinoids and the spread of Cannabis throughout the world.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136341564","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 : 2023-06-30DOI: 10.5155/eurjchem.14.2.223-230.2403
Mohammad Ali Ebrahimzadeh, Seyedeh Roya Alizadeh, Zahra Hashemi
In this study, gold nanoparticles were synthesized using the fruit extract of Sambucus ebulus (S. ebulus) as a reducing, capping, and stabilizing agent. Biogenic synthesis of gold nanoparticles (Au nanoparticles) was accomplished using S. ebulus fruit extract in the presence of hydrogen tetrachloroaurate(III) trihydrate at a temperature of 65 °C and the solution stirred at 400 rpm. The characterization of the synthesized nanoparticles (SE-AuNPs) was performed using different analytical methods, such as scanning electron microscopy (FE-SEM), energy dispersion X-ray spectroscopy (EDS), Fourier transform infrared (FT-IR), X-ray diffraction analysis (XRD), and UV-vis spectroscopy. A strong absorption peak at 565 nm confirmed the formation of the gold nanoparticle. On the basis of the electron microscopy results, AuNPs were mostly spherical with an average size of 116.2 nm. The cubic crystalline structure of the prepared nanoparticles was confirmed using the XRD pattern and the average crystallite size was obtained at 28.471 nm. FT-IR analysis confirmed the presence of functional groups in the plant extract for the synthesis of nanoparticles. SE-AuNPs showed good antibacterial activity against Gram-positive and Gram-negative bacteria tested and exhibited potent antileishmanial activity. Furthermore, SE-AuNPs showed excellent antioxidant activity that inhibited DPPH radicals with an IC50 value of 21.976 µg/mL. The prepared AuNPs acted to degrade methyl orange (MO), which was performed in sodium borohydride and visible light.
在这项研究中，金纳米颗粒的合成是由Sambucus ebulus (S. ebulus)果实提取物作为还原，封盖和稳定剂。在四氯酸氢(III)三水合物存在下，在65°C的温度下，以400转/分的转速搅拌，利用S. ebulus果提取物完成了金纳米颗粒(Au纳米颗粒)的生物合成。采用扫描电镜(FE-SEM)、能量色散x射线能谱(EDS)、傅里叶变换红外(FT-IR)、x射线衍射分析(XRD)和紫外可见光谱等分析方法对合成的SE-AuNPs进行了表征。565 nm处的强吸收峰证实了金纳米颗粒的形成。电镜结果显示，AuNPs多为球形，平均尺寸为116.2 nm。用XRD谱图证实了所制备纳米颗粒的立方晶结构，平均晶粒尺寸为28.471 nm。FT-IR分析证实了植物提取物中存在用于纳米颗粒合成的官能团。SE-AuNPs对革兰氏阳性菌和革兰氏阴性菌均表现出良好的抗菌活性，并表现出较强的抗利什曼原虫活性。SE-AuNPs具有良好的抗氧化活性，其IC50值为21.976µg/mL。制备的AuNPs在硼氢化钠和可见光条件下降解甲基橙(MO)。
{"title":"Green synthesis of gold nanoparticles using Sambucus ebulus fruit extract, characterization, and antileishmanial, antibacterial, antioxidant, and photocatalytic activities","authors":"Mohammad Ali Ebrahimzadeh, Seyedeh Roya Alizadeh, Zahra Hashemi","doi":"10.5155/eurjchem.14.2.223-230.2403","DOIUrl":"https://doi.org/10.5155/eurjchem.14.2.223-230.2403","url":null,"abstract":"In this study, gold nanoparticles were synthesized using the fruit extract of Sambucus ebulus (S. ebulus) as a reducing, capping, and stabilizing agent. Biogenic synthesis of gold nanoparticles (Au nanoparticles) was accomplished using S. ebulus fruit extract in the presence of hydrogen tetrachloroaurate(III) trihydrate at a temperature of 65 °C and the solution stirred at 400 rpm. The characterization of the synthesized nanoparticles (SE-AuNPs) was performed using different analytical methods, such as scanning electron microscopy (FE-SEM), energy dispersion X-ray spectroscopy (EDS), Fourier transform infrared (FT-IR), X-ray diffraction analysis (XRD), and UV-vis spectroscopy. A strong absorption peak at 565 nm confirmed the formation of the gold nanoparticle. On the basis of the electron microscopy results, AuNPs were mostly spherical with an average size of 116.2 nm. The cubic crystalline structure of the prepared nanoparticles was confirmed using the XRD pattern and the average crystallite size was obtained at 28.471 nm. FT-IR analysis confirmed the presence of functional groups in the plant extract for the synthesis of nanoparticles. SE-AuNPs showed good antibacterial activity against Gram-positive and Gram-negative bacteria tested and exhibited potent antileishmanial activity. Furthermore, SE-AuNPs showed excellent antioxidant activity that inhibited DPPH radicals with an IC50 value of 21.976 µg/mL. The prepared AuNPs acted to degrade methyl orange (MO), which was performed in sodium borohydride and visible light.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"163 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135967515","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 : 2023-03-31DOI: 10.5155/eurjchem.14.1.39-52.2340
Hongchang Shi
Density-functional theory (DFT) calculations at the LC-wHPBE/6-311++G(d,p) level found that the textbook three-step nitration mechanism of benzene in mixed acids was seriously wrong. Step 1 of generating nitronium ion (NO2+) is not spontaneous, the NO2+ is generated by Lewis collision, and needs to overcome a barrier Ea = 18 or 22 kcal/mol in mixed acid or in nitric acid. Obtaining the Ea of the Lewis collision by quantum chemical calculations is a highlight of the study. The reaction system (NO2+ + H2O) + HSO4⎺ or + NO3⎺ or + nH2O (n ≥ 1) can make NO2+ spontaneously change to HNO3 through a poly(≥3)-molecular acidification. Sulfuric acid can greatly reduce [H2O] and increase [NO2+]. Therefore, the nitration rate in mixed acid is much faster than that in nitric acid. Step 2, C6H6 + NO2+, is an electrophilic addition, follows the transition state theory, and needs to overcome a low barrier, ΔE* = 7 kcal/mol. The product of Step 2 is the σ-complex C6H6-NO2+. The essence of the electrophilic addition is the transfer of HOMO-1 electrons of C6H6 to LUMO of NO2+. Step 3 is a spontaneous Lewis acid-base neutralization without any barrier, and generates the target product nitrobenzene C6H5NO2. NO2+ and σ-complex are the two active intermediates in nitration. The benzene nitration rate control step is not Step 2 of generating σ-complex, but is Step 1 to generate NO2+. The DFT calculation obtains the barriers Ea and ΔE*, the reaction heats ΔHσ and ΔHp of each step of the nitration, resulting in the total nitration reaction heat ΔH = -35 kcal/mol. It is consistent with the experimental ΔH = -34 kcal/mol. Based on the results, a corrected benzene nitration three-step mechanism proposed.
{"title":"A corrected benzene nitration three-step mechanism derived by DFT calculation and MO theory","authors":"Hongchang Shi","doi":"10.5155/eurjchem.14.1.39-52.2340","DOIUrl":"https://doi.org/10.5155/eurjchem.14.1.39-52.2340","url":null,"abstract":"Density-functional theory (DFT) calculations at the LC-wHPBE/6-311++G(d,p) level found that the textbook three-step nitration mechanism of benzene in mixed acids was seriously wrong. Step 1 of generating nitronium ion (NO2+) is not spontaneous, the NO2+ is generated by Lewis collision, and needs to overcome a barrier Ea = 18 or 22 kcal/mol in mixed acid or in nitric acid. Obtaining the Ea of the Lewis collision by quantum chemical calculations is a highlight of the study. The reaction system (NO2+ + H2O) + HSO4⎺ or + NO3⎺ or + nH2O (n ≥ 1) can make NO2+ spontaneously change to HNO3 through a poly(≥3)-molecular acidification. Sulfuric acid can greatly reduce [H2O] and increase [NO2+]. Therefore, the nitration rate in mixed acid is much faster than that in nitric acid. Step 2, C6H6 + NO2+, is an electrophilic addition, follows the transition state theory, and needs to overcome a low barrier, ΔE* = 7 kcal/mol. The product of Step 2 is the σ-complex C6H6-NO2+. The essence of the electrophilic addition is the transfer of HOMO-1 electrons of C6H6 to LUMO of NO2+. Step 3 is a spontaneous Lewis acid-base neutralization without any barrier, and generates the target product nitrobenzene C6H5NO2. NO2+ and σ-complex are the two active intermediates in nitration. The benzene nitration rate control step is not Step 2 of generating σ-complex, but is Step 1 to generate NO2+. The DFT calculation obtains the barriers Ea and ΔE*, the reaction heats ΔHσ and ΔHp of each step of the nitration, resulting in the total nitration reaction heat ΔH = -35 kcal/mol. It is consistent with the experimental ΔH = -34 kcal/mol. Based on the results, a corrected benzene nitration three-step mechanism proposed.","PeriodicalId":11778,"journal":{"name":"European Journal of Chemistry","volume":"484 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135821796","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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