At present, the use of rare earth elements（REEs） has become an inevitable necessity in many modern industries. In general, liquid extraction is the best commercial method for extracting REEs due to its ability to co...At present, the use of rare earth elements（REEs） has become an inevitable necessity in many modern industries. In general, liquid extraction is the best commercial method for extracting REEs due to its ability to control high volumes of liquids with electrical load. With the aim of improving a separation technology that would be superior to the existing extraction systems, the extraction behaviors of La（Ⅲ）,Pr（Ⅲ）, and Nd（Ⅲ） from an HCI medium with Cyanex 272 in the presence of the complexing agent lactic acid（HLac） and auxiliary agents citric acid（H3 Cit）, acetic acid（HAc）, and Titriplex Ⅲ have been reported.The effect of pH and lactic acid concentration has been examined. The use of lactic acid as a complexing agent leading to a high extraction of REEs with Cyanex 272 at pH = 5 was compared with systems without lactic acid. The results show that the use of acetic acid along with lactic acid leads to an increase in the extraction percentage of LREEs. While use of citric acid and Titriplex Ⅲ reduces the extraction percentage of LREEs. Finally, the presence of Titriplex Ⅲ together with lactic acid could lead to an increase in the separation factor of Pr and Nd.展开更多
A discussion of the mechanism of nylon 6, 6 dissolving process using CaCl_2/MeOH as the sol-vent is presented. The calcium chloride forms a complex compound with nylon 6, 6 by breakingthe hydrogen bonds. The melting p...A discussion of the mechanism of nylon 6, 6 dissolving process using CaCl_2/MeOH as the sol-vent is presented. The calcium chloride forms a complex compound with nylon 6, 6 by breakingthe hydrogen bonds. The melting point of the CaCl_2 --nylon 6, 6 complex was found to be reducedby 91K relative to the pure nylon 6, 6 polymer. The role of methanol is somewhat similar to acatalyst. The results demonstrate that the complexation of a Lewis acid (CaCl_2) and a Lewis base(nylon 6, 6) can be used to probe intermolecular interactions such as hydrogen bonding in polymers, to modify the polymer properties and mediate its solubility and processing.展开更多
A new multi-branched benzoic acid rare earth complex( MBBAL-Eu( III) complex) was prepared. The advanced tested technologies were employed to characterize the composition and structure of as-prepared complex. Scanning...A new multi-branched benzoic acid rare earth complex( MBBAL-Eu( III) complex) was prepared. The advanced tested technologies were employed to characterize the composition and structure of as-prepared complex. Scanning electron microscopy( SEM) image shows that as-prepared complex has a layer structure. Transmission electron microscopy( TEM) image presents that the shape of MBBAL-Eu( III) complex is similar to oval; the size is in the range of 20-50 nm. The thermogravimetric analysis( TGA) curves of MBBAL-Eu( III) complex reveal that as-prepared complex has good thermal stability. The PET luminescence fibers with MBBAL-Eu( III) complex were prepared through meltspinning and electrospun methods. The results prove that asprepared fibers with MBBAL-Eu( III) complex have good luminescent properties and show bright red light.展开更多
The composition and structure of cyclic sulfoxide derivative Pd(IT) complexwere investigated. The coordinated number was studied with slope method. The coordination number is2 in lower acidity, but it is 3 in higher a...The composition and structure of cyclic sulfoxide derivative Pd(IT) complexwere investigated. The coordinated number was studied with slope method. The coordination number is2 in lower acidity, but it is 3 in higher acidity. Four methods, UV (ultraviolet) spectra, FUR(Fourier transform infrared) spectra, ~1H-NMR (nuclear magnetic resonance) spectra, and ^(13)C-NMRspectra, were used to determine the coordinated atom in complex. Pd is coordinated with O and S atomin S=O group in lower acidity media. The conversion of coordination bond appears with an increasingtime. Pd is coordinated with S atom in S=O group in higher acidity media, and inter-ligand-transferreaction occurs.展开更多
The metal-organic framework（MOF）{[Cu（L1）_（0.5）（CN）]·4H_2O·3DMSO}_n（1） was assembled by 1,4-bis（3？,5？-dicyano-2？,6？-di（pyrid-4-yl）-1？,4？-dihydropyridyl）benzene（L1） together with copper c...The metal-organic framework（MOF）{[Cu（L1）_（0.5）（CN）]·4H_2O·3DMSO}_n（1） was assembled by 1,4-bis（3？,5？-dicyano-2？,6？-di（pyrid-4-yl）-1？,4？-dihydropyridyl）benzene（L1） together with copper cyanide at room temperature. In 1,the Cu~＋ ions are linked by CN-anions into a 1D helical chain,which is further fused together by tetradentate L1 ligands to build an extended 3D porous framework with two different types of functionalized channels. 1 crystallizes in the monoclinic,space group P21/c with a = 17.8729（6）,b = 8.7298（3）,c = 22.7524（9） ？,β = 96.072（4）o,V = 3530.1（2） ？~3,μ = 0.845 mm-1,Dc = 1.352 Mg/m^3,Z = 4,Mr = 718.35,F（000） = 1500,S = 1.081,the final R = 0.0877 and wR = 0.2275 for 6975 observed reflections with I 〉 2σ（I）.展开更多
A new, simple, precise, selective and sensitive method for the extraction and spectrophotometric determination of niobium has been described. Mixed-ligand complexes of Niobium (V) with 2,6-dithiolphenol (DTP) and amin...A new, simple, precise, selective and sensitive method for the extraction and spectrophotometric determination of niobium has been described. Mixed-ligand complexes of Niobium (V) with 2,6-dithiolphenol (DTP) and aminophenols (AP) have been studied by spectrophotometry. Extraction of mixed-ligand complexes is maximal at pH 3.6 - 5.0. The optimal conditions for the formation and extraction of mixed-ligand compounds have been found. The molar ratio of the reacting species was 1:2:2 (Nb:DTP:AP). The Beer’s law was applicable in the range of 0.05 - 4.0 μg/ml. The method is free from common interferences. A procedure has been developed for extraction-spectrophotometric determination of Niobium in steel.展开更多
基金Project supported by Anguran Lead and Zinc Company(55/G/93)
文摘At present, the use of rare earth elements（REEs） has become an inevitable necessity in many modern industries. In general, liquid extraction is the best commercial method for extracting REEs due to its ability to control high volumes of liquids with electrical load. With the aim of improving a separation technology that would be superior to the existing extraction systems, the extraction behaviors of La（Ⅲ）,Pr（Ⅲ）, and Nd（Ⅲ） from an HCI medium with Cyanex 272 in the presence of the complexing agent lactic acid（HLac） and auxiliary agents citric acid（H3 Cit）, acetic acid（HAc）, and Titriplex Ⅲ have been reported.The effect of pH and lactic acid concentration has been examined. The use of lactic acid as a complexing agent leading to a high extraction of REEs with Cyanex 272 at pH = 5 was compared with systems without lactic acid. The results show that the use of acetic acid along with lactic acid leads to an increase in the extraction percentage of LREEs. While use of citric acid and Titriplex Ⅲ reduces the extraction percentage of LREEs. Finally, the presence of Titriplex Ⅲ together with lactic acid could lead to an increase in the separation factor of Pr and Nd.
文摘A discussion of the mechanism of nylon 6, 6 dissolving process using CaCl_2/MeOH as the sol-vent is presented. The calcium chloride forms a complex compound with nylon 6, 6 by breakingthe hydrogen bonds. The melting point of the CaCl_2 --nylon 6, 6 complex was found to be reducedby 91K relative to the pure nylon 6, 6 polymer. The role of methanol is somewhat similar to acatalyst. The results demonstrate that the complexation of a Lewis acid (CaCl_2) and a Lewis base(nylon 6, 6) can be used to probe intermolecular interactions such as hydrogen bonding in polymers, to modify the polymer properties and mediate its solubility and processing.
基金National Natural Science Foundation of China(No.51373118)Foundation Projects of Tianjin,China(No.13JCYBJC17200)
文摘A new multi-branched benzoic acid rare earth complex( MBBAL-Eu( III) complex) was prepared. The advanced tested technologies were employed to characterize the composition and structure of as-prepared complex. Scanning electron microscopy( SEM) image shows that as-prepared complex has a layer structure. Transmission electron microscopy( TEM) image presents that the shape of MBBAL-Eu( III) complex is similar to oval; the size is in the range of 20-50 nm. The thermogravimetric analysis( TGA) curves of MBBAL-Eu( III) complex reveal that as-prepared complex has good thermal stability. The PET luminescence fibers with MBBAL-Eu( III) complex were prepared through meltspinning and electrospun methods. The results prove that asprepared fibers with MBBAL-Eu( III) complex have good luminescent properties and show bright red light.
文摘The composition and structure of cyclic sulfoxide derivative Pd(IT) complexwere investigated. The coordinated number was studied with slope method. The coordination number is2 in lower acidity, but it is 3 in higher acidity. Four methods, UV (ultraviolet) spectra, FUR(Fourier transform infrared) spectra, ~1H-NMR (nuclear magnetic resonance) spectra, and ^(13)C-NMRspectra, were used to determine the coordinated atom in complex. Pd is coordinated with O and S atomin S=O group in lower acidity media. The conversion of coordination bond appears with an increasingtime. Pd is coordinated with S atom in S=O group in higher acidity media, and inter-ligand-transferreaction occurs.
基金supported by the Natural Science Foundation of Fujian Province(2012J06006,2014J05026,2006L2005)
文摘The metal-organic framework（MOF）{[Cu（L1）_（0.5）（CN）]·4H_2O·3DMSO}_n（1） was assembled by 1,4-bis（3？,5？-dicyano-2？,6？-di（pyrid-4-yl）-1？,4？-dihydropyridyl）benzene（L1） together with copper cyanide at room temperature. In 1,the Cu~＋ ions are linked by CN-anions into a 1D helical chain,which is further fused together by tetradentate L1 ligands to build an extended 3D porous framework with two different types of functionalized channels. 1 crystallizes in the monoclinic,space group P21/c with a = 17.8729（6）,b = 8.7298（3）,c = 22.7524（9） ？,β = 96.072（4）o,V = 3530.1（2） ？~3,μ = 0.845 mm-1,Dc = 1.352 Mg/m^3,Z = 4,Mr = 718.35,F（000） = 1500,S = 1.081,the final R = 0.0877 and wR = 0.2275 for 6975 observed reflections with I 〉 2σ（I）.
文摘A new, simple, precise, selective and sensitive method for the extraction and spectrophotometric determination of niobium has been described. Mixed-ligand complexes of Niobium (V) with 2,6-dithiolphenol (DTP) and aminophenols (AP) have been studied by spectrophotometry. Extraction of mixed-ligand complexes is maximal at pH 3.6 - 5.0. The optimal conditions for the formation and extraction of mixed-ligand compounds have been found. The molar ratio of the reacting species was 1:2:2 (Nb:DTP:AP). The Beer’s law was applicable in the range of 0.05 - 4.0 μg/ml. The method is free from common interferences. A procedure has been developed for extraction-spectrophotometric determination of Niobium in steel.
