The crystal structure,formation kinetics and micro-morphology of CaO·SiO2 during high-temperature sintering process were studied in low-calcium system by XRD,FT-IR,Raman and SEM-EDS methods.When the molar ratio o...The crystal structure,formation kinetics and micro-morphology of CaO·SiO2 during high-temperature sintering process were studied in low-calcium system by XRD,FT-IR,Raman and SEM-EDS methods.When the molar ratio of CaCO3 to SiO2 is 1.0,β-2CaO·SiO2 forms firstly during the heating process,and then CaO·SiO2 is generated by the transformation reaction of pre-formed 2CaO·SiO2 with SiO2.3CaO·SiO2 and 3CaO·2SiO2 do not form either in the heating or sintering process.Rising the sintering temperature and prolonging the holding time promote the phase transition of 2CaO·SiO2 to CaO·SiO2,resulting in the sintered products a small blue shift and broadening in Raman spectra.The content of CS can reach 97.4%when sintered at 1400℃ for 1 h.The formation kinetics of CaO·SiO2 follows the second-order chemical reaction model,and the corresponding apparent activation energy and pre-exponential factor are 505.82 kJ/mol and 2.16×10^14 s^−1 respectively.展开更多
The reaction between [Ru3(3-O)(-CH3CO2)6(py)2(MeOH)](PF6) (py = pyri- dine) and diphenyl-2-pyridyl-phosphine (PPh2py) gave the triruthenium cluster complex [RuIII3(3-O)(-CH3CO2)6(py)2(PPh2py)](PF6)CH2Cl2 (C40H44Cl2F6N...The reaction between [Ru3(3-O)(-CH3CO2)6(py)2(MeOH)](PF6) (py = pyri- dine) and diphenyl-2-pyridyl-phosphine (PPh2py) gave the triruthenium cluster complex [RuIII3(3-O)(-CH3CO2)6(py)2(PPh2py)](PF6)CH2Cl2 (C40H44Cl2F6N34O13P2Ru3) which was characterized by elemental analysis, IR, UV-Vis and 31P NMR spectroscopy, and X-ray single- crystal diffraction. The structure is of monoclinic, space group P21/n with a = 16.3896(1), b = 16.8773(2), c = 19.1438(2) ? b = 95.888(1), V = 5267.47(9) ?, Mr = 1324.83, Dc = 1.671 g/cm3, F(000) = 2636, m = 1.092 mm-1 and Z = 4. The final refinement gave R = 0.0508 and wR = 0.1111 for 6987 observed reflections (I > 2s(I)). Three Ru(III) atoms bridged by m3-oxo donor form an approximately isosceles triangle. The complex shows three quasireversible one- electron processes at E1/2 = 1.22 +0.03 and 1.20 V vs. Ag/AgCl.展开更多
A Cu(II) complex [CuCl(C19H20N4O)]ClO4 1 containing hydroxymethyl substituted TPA (TPA = tris(2-pyridylmethyl)amine) was prepared. It crystallizes in monoclinic, space group P21/c with a = 11.7628(2), b = 13.0083(3), ...A Cu(II) complex [CuCl(C19H20N4O)]ClO4 1 containing hydroxymethyl substituted TPA (TPA = tris(2-pyridylmethyl)amine) was prepared. It crystallizes in monoclinic, space group P21/c with a = 11.7628(2), b = 13.0083(3), c = 15.11280(10) ?, β = 108.724(2)°, V = 2190.09(7) ?3, Mr = 518.83, Z = 4, T = 293(2) K, Dc = 1.574 g/cm3, μ = 1.280 mm-1, F(000) = 1060 and S = 1.085. The final R = 0.0543 and wR = 0.1433 for 2693 observed reflections with I >2σ(I). The penta- coordinated copper (II) complex assumes an approximate square pyramidal geometry. Cyclic volta- mmetry measurement of the complex showed a quasi-reversible CuII/CuI redox couple with E1/2 = –0.467 v and ?E = 68 mv.展开更多
基金Projects(51674075,51774079)supported by the National Natural Science Foundation of ChinaProject(2018YFC1901903)supported by the National Key R&D Program of ChinaProject(N182508026)supported by the Fundamental Research Funds for the Central Universities of China。
文摘The crystal structure,formation kinetics and micro-morphology of CaO·SiO2 during high-temperature sintering process were studied in low-calcium system by XRD,FT-IR,Raman and SEM-EDS methods.When the molar ratio of CaCO3 to SiO2 is 1.0,β-2CaO·SiO2 forms firstly during the heating process,and then CaO·SiO2 is generated by the transformation reaction of pre-formed 2CaO·SiO2 with SiO2.3CaO·SiO2 and 3CaO·2SiO2 do not form either in the heating or sintering process.Rising the sintering temperature and prolonging the holding time promote the phase transition of 2CaO·SiO2 to CaO·SiO2,resulting in the sintered products a small blue shift and broadening in Raman spectra.The content of CS can reach 97.4%when sintered at 1400℃ for 1 h.The formation kinetics of CaO·SiO2 follows the second-order chemical reaction model,and the corresponding apparent activation energy and pre-exponential factor are 505.82 kJ/mol and 2.16×10^14 s^−1 respectively.
基金This work was supported by NNSFC and NSF of Fujian Province
文摘The reaction between [Ru3(3-O)(-CH3CO2)6(py)2(MeOH)](PF6) (py = pyri- dine) and diphenyl-2-pyridyl-phosphine (PPh2py) gave the triruthenium cluster complex [RuIII3(3-O)(-CH3CO2)6(py)2(PPh2py)](PF6)CH2Cl2 (C40H44Cl2F6N34O13P2Ru3) which was characterized by elemental analysis, IR, UV-Vis and 31P NMR spectroscopy, and X-ray single- crystal diffraction. The structure is of monoclinic, space group P21/n with a = 16.3896(1), b = 16.8773(2), c = 19.1438(2) ? b = 95.888(1), V = 5267.47(9) ?, Mr = 1324.83, Dc = 1.671 g/cm3, F(000) = 2636, m = 1.092 mm-1 and Z = 4. The final refinement gave R = 0.0508 and wR = 0.1111 for 6987 observed reflections (I > 2s(I)). Three Ru(III) atoms bridged by m3-oxo donor form an approximately isosceles triangle. The complex shows three quasireversible one- electron processes at E1/2 = 1.22 +0.03 and 1.20 V vs. Ag/AgCl.
基金This project was supported by "973" program of the Ministry of Science and Technology ofChina and National Natural Science Foundation of China (20376010 20128005)
文摘A Cu(II) complex [CuCl(C19H20N4O)]ClO4 1 containing hydroxymethyl substituted TPA (TPA = tris(2-pyridylmethyl)amine) was prepared. It crystallizes in monoclinic, space group P21/c with a = 11.7628(2), b = 13.0083(3), c = 15.11280(10) ?, β = 108.724(2)°, V = 2190.09(7) ?3, Mr = 518.83, Z = 4, T = 293(2) K, Dc = 1.574 g/cm3, μ = 1.280 mm-1, F(000) = 1060 and S = 1.085. The final R = 0.0543 and wR = 0.1433 for 2693 observed reflections with I >2σ(I). The penta- coordinated copper (II) complex assumes an approximate square pyramidal geometry. Cyclic volta- mmetry measurement of the complex showed a quasi-reversible CuII/CuI redox couple with E1/2 = –0.467 v and ?E = 68 mv.
