Abstract Selective oxidation of benzene to phenol is done in the liquid phase over copper-substituted LaFeO3 perovskite oxides as catalyst using H2O2 as oxidant under mild reaction conditions. Among the different copper-substituted perovskite catalysts synthesized by a novel solution combustion method, the LaFe0.90Cu0.10O3 catalyst showed highest activity (∼56 % with 100 % selectivity of phenol) and also gives better activity than the corresponding catalyst made via incipient wetness impregnation of 10 at % Cu over combustion-synthesized LaFeO3. XRD analysis revealed formation of the perovskite phase as the predominant one. The greater activity of the combustion-made catalyst has been attributed to the occurrence of a peculiar poorly-defined structure having substitutional copper ion sites on top of the LaFeO3 particle as observed in HRTEM analysis. Much less occurrence of this phase in the impregnated catalyst, where copper is primarily present as dispersed CuO crystallites, explains its comparatively lower activity in the oxidation reaction. The effect of catalyst recycling shows negligible change of activity for the combustion-made catalyst whereas the analogous impregnated catalyst shows considerable decrease in activity in recycling. This explained to be due to the essentially intact poorly-defined structure in the former and leaching of the finely dispersed CuO crystallites from the latter catalyst during cycling.
{"title":"Selective oxidation of benzene to phenol in the liquid phase over copper-substituted LaFeO3 perovskite oxide as catalyst","authors":"Rajib Mistri","doi":"10.1515/znb-2023-0016","DOIUrl":"https://doi.org/10.1515/znb-2023-0016","url":null,"abstract":"Abstract Selective oxidation of benzene to phenol is done in the liquid phase over copper-substituted LaFeO3 perovskite oxides as catalyst using H2O2 as oxidant under mild reaction conditions. Among the different copper-substituted perovskite catalysts synthesized by a novel solution combustion method, the LaFe0.90Cu0.10O3 catalyst showed highest activity (∼56 % with 100 % selectivity of phenol) and also gives better activity than the corresponding catalyst made via incipient wetness impregnation of 10 at % Cu over combustion-synthesized LaFeO3. XRD analysis revealed formation of the perovskite phase as the predominant one. The greater activity of the combustion-made catalyst has been attributed to the occurrence of a peculiar poorly-defined structure having substitutional copper ion sites on top of the LaFeO3 particle as observed in HRTEM analysis. Much less occurrence of this phase in the impregnated catalyst, where copper is primarily present as dispersed CuO crystallites, explains its comparatively lower activity in the oxidation reaction. The effect of catalyst recycling shows negligible change of activity for the combustion-made catalyst whereas the analogous impregnated catalyst shows considerable decrease in activity in recycling. This explained to be due to the essentially intact poorly-defined structure in the former and leaching of the finely dispersed CuO crystallites from the latter catalyst during cycling.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"64 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85589726","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}
Abstract By utilizing the well-known selective xanthine oxidase inhibitor topiroxostat, a new zinc(II) complex Zn(L)2(H2O)2 (1) [HL = 4-(3-(pyridine-4-yl)-1H-1,2,4-triazol-5-yl)picolinic acid] has been hydrothermally synthesized, involving in-situ ligand formation upon hydrolysis of topiroxostat. The complex has been structurally characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. X-ray structural analysis revealed that complex 1 is a N,O-chelating mononuclear Zn(II) complex. Complex 1 shows good thermal stability and exhibits photoluminescence in the solid state at room temperature. Moreover, complex 1 has been shown to be effective in the solvent-free ring-opening polymerization of ε-caprolactone without any co-catalyst or initiator.
{"title":"Synthesis, characterization, luminescence, and catalytic properties of a zinc(II) complex with a N,O-donor ligand generated in situ from topiroxostat","authors":"Chenwanli Qin, Zhong‐Hua Sun, Xin Rong, Sheng-Chun Chen, Mingyang He, Qun Chen","doi":"10.1515/znb-2022-0148","DOIUrl":"https://doi.org/10.1515/znb-2022-0148","url":null,"abstract":"Abstract By utilizing the well-known selective xanthine oxidase inhibitor topiroxostat, a new zinc(II) complex Zn(L)2(H2O)2 (1) [HL = 4-(3-(pyridine-4-yl)-1H-1,2,4-triazol-5-yl)picolinic acid] has been hydrothermally synthesized, involving in-situ ligand formation upon hydrolysis of topiroxostat. The complex has been structurally characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. X-ray structural analysis revealed that complex 1 is a N,O-chelating mononuclear Zn(II) complex. Complex 1 shows good thermal stability and exhibits photoluminescence in the solid state at room temperature. Moreover, complex 1 has been shown to be effective in the solvent-free ring-opening polymerization of ε-caprolactone without any co-catalyst or initiator.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"31 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91487419","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}
Ying-Jun Chen, Peipei Yin, Shusu Ren, Zhihui Li, Xiao-Gang Yang
Abstract A metal-organic framework (MOF) {[Cd(EtOIPA)(bpp)(H2O)]·2H2O} n (1) has been synthesized under basic hydrothermal conditions by using of 5-ethoxyisophthalic acid (EtOIPAH2) and 1,3-bis(4-pyridyl)propane (bpp) as reagents for cadmium nitrate. Compound 1 was characterized by elemental analysis, single-crystal X-ray diffraction and UV/Vis spectroscopy. In 1, the bpp ligands extend the EtOIPA-Cd chains along the ab plane to form a 2-fold 3D interpenetrating network. Compound 1 emits blue phosphorescence at room temperature with a long lifetime of 4.2 ms.
{"title":"A Cd(II) MOF based on 5-ethoxyisophthalate and 1,3-bis(4-pyridyl)propane ligands with a twofold interpenetrated crystal structure showing room temperature phosphorescence","authors":"Ying-Jun Chen, Peipei Yin, Shusu Ren, Zhihui Li, Xiao-Gang Yang","doi":"10.1515/znb-2023-0019","DOIUrl":"https://doi.org/10.1515/znb-2023-0019","url":null,"abstract":"Abstract A metal-organic framework (MOF) {[Cd(EtOIPA)(bpp)(H2O)]·2H2O} n (1) has been synthesized under basic hydrothermal conditions by using of 5-ethoxyisophthalic acid (EtOIPAH2) and 1,3-bis(4-pyridyl)propane (bpp) as reagents for cadmium nitrate. Compound 1 was characterized by elemental analysis, single-crystal X-ray diffraction and UV/Vis spectroscopy. In 1, the bpp ligands extend the EtOIPA-Cd chains along the ab plane to form a 2-fold 3D interpenetrating network. Compound 1 emits blue phosphorescence at room temperature with a long lifetime of 4.2 ms.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81281456","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}
Galyna P. Nychyporuk, N. Dominyuk, I. Muts, A. Zelinskiy, Rainer Pöttgen, V. Zaremba
Abstract The solid solutions LaNiIn1–xSn x and CeNiIn1–xSn x were studied by means of X-ray powder diffraction and EDX analyses in the full concentration range for samples annealed at T = 870 K. The limited solubility of the fourth component in the starting compounds with equiatomic composition, and the limits and the unit cell parameters of the solid solutions have been determined. The crystal structure of CeNiIn0.57Sn0.43 was refined from single-crystal X-ray diffraction data: ZrNiAl-type structure; hexagonal space group P 6 ‾ $overline{6}$ 2m, a = 0.74213(10), c = 0.40825(8) nm, R1 = 0.0155, wR2 = 0.0303, 282 independent hkl reflections and 15 refined parameters. The existence ranges within the solid solutions are discussed.
{"title":"LaNiIn1–xSn x and CeNiIn1–xSn x solid solutions at T = 870 K","authors":"Galyna P. Nychyporuk, N. Dominyuk, I. Muts, A. Zelinskiy, Rainer Pöttgen, V. Zaremba","doi":"10.1515/znb-2023-0036","DOIUrl":"https://doi.org/10.1515/znb-2023-0036","url":null,"abstract":"Abstract The solid solutions LaNiIn1–xSn x and CeNiIn1–xSn x were studied by means of X-ray powder diffraction and EDX analyses in the full concentration range for samples annealed at T = 870 K. The limited solubility of the fourth component in the starting compounds with equiatomic composition, and the limits and the unit cell parameters of the solid solutions have been determined. The crystal structure of CeNiIn0.57Sn0.43 was refined from single-crystal X-ray diffraction data: ZrNiAl-type structure; hexagonal space group P 6 ‾ $overline{6}$ 2m, a = 0.74213(10), c = 0.40825(8) nm, R1 = 0.0155, wR2 = 0.0303, 282 independent hkl reflections and 15 refined parameters. The existence ranges within the solid solutions are discussed.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"17 1","pages":"427 - 433"},"PeriodicalIF":0.0,"publicationDate":"2023-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84339688","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}
Abstract The N-heterocyclic stannylene [Fe{(η5-C5H4)NC6H3-2,6-iPr2}2Sn] (1) has been synthesised from SnCl2 and the lithium amide [Fe{(η5-C5H4)NC6H3-2,6-iPr2}2Li2]. Compound 1 is inert towards H2, CO, CO2, and MeI under ambient conditions. Immediate hydrolysis and ammonolysis was observed with H2O and NH3, respectively. While oxidation reactions of 1 with chalcogens (O2, S8, Se8) afforded only intractable material, the reaction with Ph2Se2 cleanly furnished [Fe{(η5-C5H4)NC6H3-2,6-iPr2}2Sn(SePh)2] (2). Compounds 1 and 2 have been structurally characterised by single-crystal X-ray diffraction. Compound 2 exhibits an intramolecular CH⋯Se contact compatible with a weak hydrogen bond.
{"title":"Synthesis, structure, and reactivity of the ferrocene-based N-heterocyclic stannylene [Fe{(η5-C5H4)NC6H3-2,6-iPr2}2Sn]","authors":"N. Weyer, C. Bruhn, U. Siemeling","doi":"10.1515/znb-2023-0035","DOIUrl":"https://doi.org/10.1515/znb-2023-0035","url":null,"abstract":"Abstract The N-heterocyclic stannylene [Fe{(η5-C5H4)NC6H3-2,6-iPr2}2Sn] (1) has been synthesised from SnCl2 and the lithium amide [Fe{(η5-C5H4)NC6H3-2,6-iPr2}2Li2]. Compound 1 is inert towards H2, CO, CO2, and MeI under ambient conditions. Immediate hydrolysis and ammonolysis was observed with H2O and NH3, respectively. While oxidation reactions of 1 with chalcogens (O2, S8, Se8) afforded only intractable material, the reaction with Ph2Se2 cleanly furnished [Fe{(η5-C5H4)NC6H3-2,6-iPr2}2Sn(SePh)2] (2). Compounds 1 and 2 have been structurally characterised by single-crystal X-ray diffraction. Compound 2 exhibits an intramolecular CH⋯Se contact compatible with a weak hydrogen bond.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89033625","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}
B. Belan, M. Dzevenko, D. Kowalska, R. Gladyshevskii
Abstract The ternary silicide ErNi4.04Si0.96 was synthesized by arc-melting of stoichiometric quantities of the elements, and its crystal structure has been determined using single-crystal X-ray diffraction data. The compound crystallizes in the CaCu5 structure type: hexagonal space group P6/mmm, Pearson code hP6, Z = 1; a = 4.874(3), c = 3.959(2) Å, V = 81.5(1) Å3; R1 = 0.0239, wR2 = 0.0503, for 67 independent reflections with I > 2σ(I) and eight variables. The erbium and nickel atoms occupy the crystallographic positions 1a and 2c, respectively. The position 3g is occupied by a mixture of Ni and Si atoms. The structure of this silicide represents a packing of bipyramidal units built from nickel and Ni/Si atoms.
摘要采用化学计量量电弧熔合法制备了三元硅化物ErNi4.04Si0.96，并利用单晶x射线衍射数据测定了其晶体结构。化合物结晶为ccu5结构类型:六边形空间群P6/mmm, Pearson编码hP6, Z = 1;a = 4.874(3)， c = 3.959(2) Å， V = 81.5(1) Å3;R1 = 0.0239, wR2 = 0.0503，对于67个I > 2σ(I)， 8个变量的独立反射。铒原子和镍原子分别占据晶体位置1a和2c。位置3g被Ni原子和Si原子的混合物占据。这种硅化物的结构代表了由镍和Ni/Si原子构成的双锥体单元的堆积。
{"title":"Crystal structure of the ternary silicide ErNi4.04Si0.96","authors":"B. Belan, M. Dzevenko, D. Kowalska, R. Gladyshevskii","doi":"10.1515/znb-2023-0014","DOIUrl":"https://doi.org/10.1515/znb-2023-0014","url":null,"abstract":"Abstract The ternary silicide ErNi4.04Si0.96 was synthesized by arc-melting of stoichiometric quantities of the elements, and its crystal structure has been determined using single-crystal X-ray diffraction data. The compound crystallizes in the CaCu5 structure type: hexagonal space group P6/mmm, Pearson code hP6, Z = 1; a = 4.874(3), c = 3.959(2) Å, V = 81.5(1) Å3; R1 = 0.0239, wR2 = 0.0503, for 67 independent reflections with I > 2σ(I) and eight variables. The erbium and nickel atoms occupy the crystallographic positions 1a and 2c, respectively. The position 3g is occupied by a mixture of Ni and Si atoms. The structure of this silicide represents a packing of bipyramidal units built from nickel and Ni/Si atoms.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90491201","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}
O. Reckeweg, F. Lissner, Björn Blaschkowski, T. Schleid
Abstract Metathesis reactions designed to produce nominally the pseudo-ternary ATl[N(CN)2]2 compounds (A = Li, Na, K, Rb or Cs) either yielded solid solutions or separated pseudo-binary dicyanamides next to the new compounds LiTl[N(CN)2]2 and Tl0.89(1)Cs0.11(1)[N(CN)2]. Tetragonal LiTl[N(CN)2]2 (a = 724.96(2), c = 1411.77(6) pm, Z = 4) is crystallizing isotypically with LiK[N(CN)2]2 in the space group I4/mcm, while orthorhombic Tl0.89(1)Cs0.11(1)[N(CN)2] (a = 858.19(4), b = 654.22(2), c = 738.94(4) pm, Z = 4) adopts the α-K[N(CN)2]-type structure in the space group Pbcm, which Tl[N(CN)2] itself also assumes, with the unique cationic position shared by Tl+ and Cs+ in an approximate 9:1 molar ratio. The Raman spectra of the new compounds are presented and compared to those of Tl[N(CN)2], LiK[N(CN)2]2 and LiRb[N(CN)2]2.
摘要为生成名义上的伪三元ATl[N(CN)2]2化合物(A = Li, Na, K, Rb或Cs)而设计的复分解反应，在新化合物LiTl[N(CN)2]2和Tl0.89(1)Cs0.11(1)[N(CN)2]旁边，要么生成固形物，要么分离出伪二元双氰胺。正方LiTl[N(CN)2]2 (a = 724.96(2)， c = 1411.77(6) pm, Z = 4)在I4/mcm空间群中与LiK[N(CN)2]2等晶，而正交Tl0.89(1)Cs0.11(1)[N(CN)2] (a = 858.19(4)， b = 654.22(2)， c = 738.94(4) pm, Z = 4)在Pbcm空间群中采用α-K[N(CN)2]型结构，Tl[N(CN)2]本身也具有独特的阳离子位置，Tl+和Cs+以约9:1 的摩尔比共享。得到了新化合物的拉曼光谱，并与Tl[N(CN)2]、LiK[N(CN)2]2和LiRb[N(CN)2]2进行了比较。
{"title":"About the pseudo-ternary alkali metal-thallium(I) dicyanamide systems","authors":"O. Reckeweg, F. Lissner, Björn Blaschkowski, T. Schleid","doi":"10.1515/znb-2023-0024","DOIUrl":"https://doi.org/10.1515/znb-2023-0024","url":null,"abstract":"Abstract Metathesis reactions designed to produce nominally the pseudo-ternary ATl[N(CN)2]2 compounds (A = Li, Na, K, Rb or Cs) either yielded solid solutions or separated pseudo-binary dicyanamides next to the new compounds LiTl[N(CN)2]2 and Tl0.89(1)Cs0.11(1)[N(CN)2]. Tetragonal LiTl[N(CN)2]2 (a = 724.96(2), c = 1411.77(6) pm, Z = 4) is crystallizing isotypically with LiK[N(CN)2]2 in the space group I4/mcm, while orthorhombic Tl0.89(1)Cs0.11(1)[N(CN)2] (a = 858.19(4), b = 654.22(2), c = 738.94(4) pm, Z = 4) adopts the α-K[N(CN)2]-type structure in the space group Pbcm, which Tl[N(CN)2] itself also assumes, with the unique cationic position shared by Tl+ and Cs+ in an approximate 9:1 molar ratio. The Raman spectra of the new compounds are presented and compared to those of Tl[N(CN)2], LiK[N(CN)2]2 and LiRb[N(CN)2]2.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"13 1","pages":"373 - 379"},"PeriodicalIF":0.0,"publicationDate":"2023-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82272093","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}
Abstract Diphenyl(pentachlorophenyl)phosphanegold(I) chloride was synthesized and characterized via NMR spectroscopy, elemental analysis and X-ray diffraction.
摘要合成了二苯基(五氯苯基)磷酸金(I)氯，并通过核磁共振、元素分析和x射线衍射对其进行了表征。
{"title":"Synthesis and characterization of diphenyl(pentachlorophenyl)phosphanegold(I) chloride","authors":"Peter Heinrichs, H. Stammler, N. Mitzel","doi":"10.1515/znb-2023-0029","DOIUrl":"https://doi.org/10.1515/znb-2023-0029","url":null,"abstract":"Abstract Diphenyl(pentachlorophenyl)phosphanegold(I) chloride was synthesized and characterized via NMR spectroscopy, elemental analysis and X-ray diffraction.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"9 1","pages":"395 - 397"},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83425521","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}
Media Mohamad, Jessica Lambert, Lisa Wirtz, B. Morgenstern, A. Schäfer
Abstract (Pyrrolidinyldimethylsilyl)tetramethylcyclopentadienide complexes of lithium, sodium and potassium were synthesized and characterized, including crystal structure determinations. The lithium cyclopentadienide compound was used as a Cp transfer reagent to prepare the corresponding ferrocene, stannocene and plumbocene.
{"title":"Aminosilyl-substituted cyclopentadienyl complexes of alkali metals","authors":"Media Mohamad, Jessica Lambert, Lisa Wirtz, B. Morgenstern, A. Schäfer","doi":"10.1515/znb-2023-0012","DOIUrl":"https://doi.org/10.1515/znb-2023-0012","url":null,"abstract":"Abstract (Pyrrolidinyldimethylsilyl)tetramethylcyclopentadienide complexes of lithium, sodium and potassium were synthesized and characterized, including crystal structure determinations. The lithium cyclopentadienide compound was used as a Cp transfer reagent to prepare the corresponding ferrocene, stannocene and plumbocene.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"520 1","pages":"363 - 368"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77805873","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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