Different mathematical methods, including linearization, differential, integration and nonlinear least squares approximation (Newton-Marquardt method), were used to fit different kinetic equations, such as zero-order,...Different mathematical methods, including linearization, differential, integration and nonlinear least squares approximation (Newton-Marquardt method), were used to fit different kinetic equations, such as zero-order, first-order (i. e, membrane diffusion), second-order, parabolic-diffusion, Elovich, two-constant equations, to the experimental data of Pb2+ and Cu2+ adsorption on variable charge soils and kaolinite. Assuming each M2+ occupied two adsorption sites, two more equations, the so-called surface second-order equation and third-order equation were derived and compared with the above equations according to the fitting results, which showed that the second-order equation and surface second-order equation, being one equation in different expressions under some conditions, were better than the other equations in describing the Pb2+ and Cu2+ adsorption kinetics, and the latter was the best.展开更多
The hydrothermal reaction of isonicotinic acid (4-C5H4N-COOH), Cu(ClO4)(2). 6H(2)O and water at 170 degreesC gave the title compound, [Cu(OH)(2)(H2O)(2)(4-C5H4N-COOH)(2)] (1), which was analyzed by single-crystal X-ra...The hydrothermal reaction of isonicotinic acid (4-C5H4N-COOH), Cu(ClO4)(2). 6H(2)O and water at 170 degreesC gave the title compound, [Cu(OH)(2)(H2O)(2)(4-C5H4N-COOH)(2)] (1), which was analyzed by single-crystal X-ray diffraction, The complex crystallizes in triclinic space group PY with unit cell parameters: a = 6.337(2), b = 6.894(3), c = 9.178(3). alpha = 99.40(3), beta = 105.26(3), gamma 108.17(5)degrees, V = 354.1(2)Angstrom (3), Z = 1, C12H16CuN2O8, M-r = 379.81, D-c = 1.791 Mg/m(3), F(000) 197, mu (MoK alpha) = 1.589 mm(-1). The final R and wR are 0.068 and 0.170 for 1249 observed reflections with I greater than or equal to2 sigma (I). The central copper ion is in a distorted octahedron geometry completed by two nitrogen atoms from carboxylic ligand, two oxygen atoms from hydroxyl groups and two oxygen atoms from coordinated water molecules. The intermolecular hydrogen bonding leads to the formation of a three-dimensional supramolecular structure.展开更多
The title complex, [Cu(L)Cl2]n (L = 2,5-di-2-pyridyl-1,3,4-oxodiazole) 1, has been obtained from the reaction of 3,6-di-2-pyridyl-1,2,4,5-tetrazine (bptz) and CuCl2?H2O in a mixture solvent of CH3CN and CH2Cl2 (L is g...The title complex, [Cu(L)Cl2]n (L = 2,5-di-2-pyridyl-1,3,4-oxodiazole) 1, has been obtained from the reaction of 3,6-di-2-pyridyl-1,2,4,5-tetrazine (bptz) and CuCl2?H2O in a mixture solvent of CH3CN and CH2Cl2 (L is generated from the metal-assisted hydrolysis reaction of bptz) and structurally characterized. It crystallizes in space group C2/c of monoclinic system with cell parameters: a = 9.812(2), b = 12.679(3), c = 11.111(2) ? b = 103.92(3)? V = 1341.6(5) 3, Z = 4, Dc = 1.776 g/cm3, Mr = 358.66, F(000) = 716, ?= 2.024 mm1 and S = 1.004. The final R = 0.0346 and wR = 0.0938 for 1011 observed reflections with I > 2(I). The Cu(Ⅱ) ion is six-coordinated by four N atoms of two L ligands and two Cl ions in a distorted octahedral geometry. The ligand L acts as a bis-bidentate ligand to bridge the Cu(Ⅱ) ions, resulting in an infinite chain structure.展开更多
铜离子是植物生命活动必需的微量矿质元素。主要研究不同质量浓度的Cu2+对苦荞发芽势和发芽率、谷氨酸脱羧酶(GAD)活性及γ-氨基丁酸(GABA)形成的影响。结果表明,Cu2+对苦荞萌发具有低质量浓度(0.1 m g/L^0.5 mg/L)下的刺激效应,可明显...铜离子是植物生命活动必需的微量矿质元素。主要研究不同质量浓度的Cu2+对苦荞发芽势和发芽率、谷氨酸脱羧酶(GAD)活性及γ-氨基丁酸(GABA)形成的影响。结果表明,Cu2+对苦荞萌发具有低质量浓度(0.1 m g/L^0.5 mg/L)下的刺激效应,可明显提高苦荞发芽势和发芽率;以Cu2+质量浓度为0.2 mg/L处理苦荞,第4天时GABA的含量达到最高值。展开更多
基金Project supported by the N ational Natural Science Foundation of China.
文摘Different mathematical methods, including linearization, differential, integration and nonlinear least squares approximation (Newton-Marquardt method), were used to fit different kinetic equations, such as zero-order, first-order (i. e, membrane diffusion), second-order, parabolic-diffusion, Elovich, two-constant equations, to the experimental data of Pb2+ and Cu2+ adsorption on variable charge soils and kaolinite. Assuming each M2+ occupied two adsorption sites, two more equations, the so-called surface second-order equation and third-order equation were derived and compared with the above equations according to the fitting results, which showed that the second-order equation and surface second-order equation, being one equation in different expressions under some conditions, were better than the other equations in describing the Pb2+ and Cu2+ adsorption kinetics, and the latter was the best.
文摘The hydrothermal reaction of isonicotinic acid (4-C5H4N-COOH), Cu(ClO4)(2). 6H(2)O and water at 170 degreesC gave the title compound, [Cu(OH)(2)(H2O)(2)(4-C5H4N-COOH)(2)] (1), which was analyzed by single-crystal X-ray diffraction, The complex crystallizes in triclinic space group PY with unit cell parameters: a = 6.337(2), b = 6.894(3), c = 9.178(3). alpha = 99.40(3), beta = 105.26(3), gamma 108.17(5)degrees, V = 354.1(2)Angstrom (3), Z = 1, C12H16CuN2O8, M-r = 379.81, D-c = 1.791 Mg/m(3), F(000) 197, mu (MoK alpha) = 1.589 mm(-1). The final R and wR are 0.068 and 0.170 for 1249 observed reflections with I greater than or equal to2 sigma (I). The central copper ion is in a distorted octahedron geometry completed by two nitrogen atoms from carboxylic ligand, two oxygen atoms from hydroxyl groups and two oxygen atoms from coordinated water molecules. The intermolecular hydrogen bonding leads to the formation of a three-dimensional supramolecular structure.
基金This work was supported by the National Natural Science Foundation of China (No.20001007 20131020) Natural Science Foundation of the Chinese Academy of Sciences (KJCX2-H3) and Fujian province (2000F006)
文摘The title complex, [Cu(L)Cl2]n (L = 2,5-di-2-pyridyl-1,3,4-oxodiazole) 1, has been obtained from the reaction of 3,6-di-2-pyridyl-1,2,4,5-tetrazine (bptz) and CuCl2?H2O in a mixture solvent of CH3CN and CH2Cl2 (L is generated from the metal-assisted hydrolysis reaction of bptz) and structurally characterized. It crystallizes in space group C2/c of monoclinic system with cell parameters: a = 9.812(2), b = 12.679(3), c = 11.111(2) ? b = 103.92(3)? V = 1341.6(5) 3, Z = 4, Dc = 1.776 g/cm3, Mr = 358.66, F(000) = 716, ?= 2.024 mm1 and S = 1.004. The final R = 0.0346 and wR = 0.0938 for 1011 observed reflections with I > 2(I). The Cu(Ⅱ) ion is six-coordinated by four N atoms of two L ligands and two Cl ions in a distorted octahedral geometry. The ligand L acts as a bis-bidentate ligand to bridge the Cu(Ⅱ) ions, resulting in an infinite chain structure.
文摘铜离子是植物生命活动必需的微量矿质元素。主要研究不同质量浓度的Cu2+对苦荞发芽势和发芽率、谷氨酸脱羧酶(GAD)活性及γ-氨基丁酸(GABA)形成的影响。结果表明,Cu2+对苦荞萌发具有低质量浓度(0.1 m g/L^0.5 mg/L)下的刺激效应,可明显提高苦荞发芽势和发芽率;以Cu2+质量浓度为0.2 mg/L处理苦荞,第4天时GABA的含量达到最高值。
