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Structure and Two-dimensional Correlation Infrared Spectroscopy Study of a New One-dimensional Chain Compound: (4,4’-Hbpy)_3[NaMo_8O_(26)](4,4’- bpy)_2(H_2O)_4 (bpy = Bipydine) 被引量:2
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作者 陈义平 张汉辉 +3 位作者 柯大梅 沈小敏 黄长沧 孙瑞卿 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第9期1033-1038,共6页
A novel compound, (4,4'-Hbpy)3[NaMo8O26](4,4'-bpy)2(H2O)4 1 (bpy=bipydine), was synthesized by the hydrothermal method. Single-crystal X-ray diffraction shows that compound 1 belongs to the monoclinic system... A novel compound, (4,4'-Hbpy)3[NaMo8O26](4,4'-bpy)2(H2O)4 1 (bpy=bipydine), was synthesized by the hydrothermal method. Single-crystal X-ray diffraction shows that compound 1 belongs to the monoclinic system, space group C2/m with a=19.1921(5), b=18.6931(6), c=9.3821(3) A° β=104.8020(11)°, V=3254.22(17)A°^3 C50H51Mo8N10NaO30, Mr=2062.52, Z=2, F(000)=2016, μ=1.591 mm^-1 and Dc=2.105 g/cm^3. The final R=0.0283 and wR=0.0912 for 3118 observed reflections (I〉20(I)). Compound 1 contains the β-[Mo8O26]^4-anion, sodium ion, 4,4'-bpy and lattice crystalline water molecules. The β-[MosO26] units link the sodium ion to form a chain structure. The infinitechains of [Na(Mo8O26)]^3- blocks are surrounded by protonized 4,4'-bpy cations, 4,4'-bpy and lattice crystalline water molecules. The 2D-IR correlation spectroscopy study indicates that the stretching vibrations of Mo=O occur more preferentially due to the thermal effect. The TGA analysis shows that compound 1 has high thermal stability. 展开更多
关键词 OCTAMOLYBDATE sodium ion two-dimensional infrared 2D-IR) correlation spectroscopy
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Evolution of Two-Dimensional Correlation Spectroscopy
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作者 Isao Noda 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2016年第S1期3-4,共2页
A number of useful techniques associated with two-dimensional correlation spectroscopy(2DCOS)to improve its performance and utility have been developed in the last 30years.Evolution of these 2DCOS techniques,including... A number of useful techniques associated with two-dimensional correlation spectroscopy(2DCOS)to improve its performance and utility have been developed in the last 30years.Evolution of these 2DCOS techniques,including some of the very recent developments,is reviewed with examples.Topics include merged or modified asynchronous 2Dcorrelation spectrum,two-dimensional codistribution spectroscopy(2DCDS),Pareto scaling,and null-space projection treatment of spectral dataset. 展开更多
关键词 two-dimensional correlation spectroscopy 2dcos 2DCDS Merged 2D Pareto scaling Nullspace projection
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Generalized two-dimensional correlation near-infrared spectroscopy and principal component analysis of the structures of methanol and ethanol 被引量:5
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作者 Liu Hao Xu JianPing +1 位作者 Qu LingBo Xiang BingRen 《Science China Chemistry》 SCIE EI CAS 2010年第5期1154-1159,共6页
Liquid state methanol and ethanol under different temperatures have been investigated by FT-NIR(Fourier transform nearinfrared) spectroscopy,generalized two-dimensional(2D) correlation spectroscopy,and PCA(principal c... Liquid state methanol and ethanol under different temperatures have been investigated by FT-NIR(Fourier transform nearinfrared) spectroscopy,generalized two-dimensional(2D) correlation spectroscopy,and PCA(principal component analysis) . First,the FT-NIR spectra were measured over a temperature range of 30-64(or 30-71) °C,and then the 2D correlation spectra were computed.Combining near-infrared spectroscopy,generalized 2D correlation spectroscopy,and references,we analyzed the molecular structures(especially the hydrogen bond) of methanol and ethanol,and performed the NIR band assignments. The PCA method was employed to verify the results of the 2D analysis.This study will be helpful to the understanding of these reagents. 展开更多
关键词 NIR(near-infrared) two-dimensional (2D) correlation spectroscopy principal component analysis (PCA) METHANOL ETHANOL
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Two-dimension fluorescence correlation spectroscopy to characterize the binding of organic ligands with zinc in eutrophic lake 被引量:3
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作者 Xin Liu Hua Lv Hua-Cheng Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第2期205-209,共5页
Metal binding of organic ligands can definitely affect its environmental behavior in waters,while information on the binding heterogeneity with different organic ligands is still lacked till now.In this study,the bind... Metal binding of organic ligands can definitely affect its environmental behavior in waters,while information on the binding heterogeneity with different organic ligands is still lacked till now.In this study,the binding of zinc with organic matters associated with cyanobacterial blooms,including dissolved organic matters(DOM) and attached organic matters(AOM),were studied by using fluorescence quenching titration combined with two-dimensional correlation spectroscopy(2D-COS).Metal-induced fluorescent quenching was obviously observed both for DOM and AOM,indicating the formation of metal-ligand complexes.Compared with the one-dimensional spectra,2D-COS revealed the sequences of metal-ligand interaction with the following orders:276 nm 〉 232 ran for DOM and232 nm 〉 276 nm for AOM.Furthermore,the modified Stern-Volmer model showed that the binding constant(logKM) of 276 nm in DOM was higher than that of 232 nm(4.93 vs.4.51),while AOM was characterized with a high binding affinity for 232 nm(log KM:4.83).The ranks of log KM values were consistent with the sequential orders derived from 2D-COS results both for the two samples.Fluorescence quenching titration combined with 2D-COS was an effective method to characterize the metal-ligand interaction. 展开更多
关键词 Metal binding Eutrophic lakes Dissolved organic matters(DOM) Attached organic matters(AOM) two-dimensional correlation spectroscopy2D-COS)
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Evolution of humic substances in polymerization of polyphenol and amino acid based on non-destructive characterization 被引量:1
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作者 Jianmei Zou Jianzhi Huang +1 位作者 Huichun Zhang Dongbei Yue 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2021年第1期91-100,共10页
Abiotic humification is important in the formation and evolution of organic matter in soil and compost maturing processes.However,the roles of metal oxides in abiotic humification reactions under micro-aerobic remain ... Abiotic humification is important in the formation and evolution of organic matter in soil and compost maturing processes.However,the roles of metal oxides in abiotic humification reactions under micro-aerobic remain ambiguous.The aim of this study was to use non-destructive measurement methods to investigate the role of MnO_(2) in the evolution of humic substances(HSs)during oxidative polymerization of polyphenol-amino acid.Our results suggested a synergistic effect between MnO_(2) and O_(2) in promoting the polymerization reaction and identified that MnO_(2) alone had a limited ability in accelerating the transformation of fulvic acid(FA)to humic acid(HA),whereas O_(2) was the key factor in the process.Two-dimensional correlation spectroscopy(2D-COS)showed that the evolution in the UV-vis spectra followed the order of 475–525 nm>300–400 nm>240–280 nm in the humification process,indicating the formation of simple organic matter followed by FA and then HA.13C nuclear magnetic resonance(13C NMR)analysis revealed that the products under both air and N2 conditions in the presence of MnO_(2) had greater amounts of aromatic-C than in the absence of MnO_(2),demonstrating that MnO_(2) affected the structure of the humification products.The results of this study provided new insights into the theory of abiotic humification. 展开更多
关键词 two-dimensional correlation spectroscopy(2D-COS) Humic substances(HSs) HUMIFICATION Manganese dioxide POLYPHENOL
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