Superfine composite powders of CeO2-ZrO2 (CZ) and CeO2-ZrO2-La2O3 (CZL) were prepared by hydrothermal method. The effects of pH?temperature and time for hydrothermal process on the performance of the resulting powders...Superfine composite powders of CeO2-ZrO2 (CZ) and CeO2-ZrO2-La2O3 (CZL) were prepared by hydrothermal method. The effects of pH?temperature and time for hydrothermal process on the performance of the resulting powders were studied. The optimized reaction parameters were on follows: the precursor′s pH≈9.0, hydrothermal temperature of 200 ℃ holding for 2 h. Thermal stable powders with average particle size smaller than 10 nm and specific surface area of 171 m2·g-1 were obtained. A BET specific surface area was still at 44 m2·g-1 after calcination at 1 000 ℃ for 6 hours.展开更多
The crystal structure of {[Cd(sulfadiazine)2]n[Cd(sulfadiazine)2·H2O]n} (1) comprises of two different Cd centers in which sulfadiazine is used as a quadridentate and bidentate ligand to coordinate to Cd1 center,...The crystal structure of {[Cd(sulfadiazine)2]n[Cd(sulfadiazine)2·H2O]n} (1) comprises of two different Cd centers in which sulfadiazine is used as a quadridentate and bidentate ligand to coordinate to Cd1 center, while it acts as a tridentate and bidentate ligand to bridge to Cd2 center, and the oxygen atom from water also coordinates to Cd2 center. As a result, the title compound bears two different 1D chain. CCDC: 274945.展开更多
A novel one-dimensional coordination polymer, [Cd( μ-DPIA)2(H2O)]n (HDPIA=4,5-Diphenylimidazole-1-acetic acid), was synthesized and characterized by the element analysis, IR and single crystal X-ray diffraction. It c...A novel one-dimensional coordination polymer, [Cd( μ-DPIA)2(H2O)]n (HDPIA=4,5-Diphenylimidazole-1-acetic acid), was synthesized and characterized by the element analysis, IR and single crystal X-ray diffraction. It crystallizes in the orthogonal space group Pca21 with unit cell parameters: a=1.509 6(3) nm, b=0.611 1(1) nm, c=3.216 4(6) nm, and V=2.967 1(10) nm3, Z=4, R=0.032 7, wR=0.086 7. The Cd atom is seven-coordinated by four O atoms and two N atoms from two chelating DPIA- ligands and one water molecule, and displays a distorted pentagonal bipyramid coordination geometry. Each DPIA- ligand bridges two adjacent Cd atoms, forming a infinite chain along the a axis direction. The Cd...Cd separation within the polymer is 0.765 0(3) nm. A layer structure which parallels to the ab plane is further constructed by hydrogen bonding interactions. CCDC: 254247.展开更多
The effects of solidification rate, modifications and pouring temperature on the microstructure and mechanical properties of casting zinc aluminum alloy ZA27 have been investigated. The results show that the number an...The effects of solidification rate, modifications and pouring temperature on the microstructure and mechanical properties of casting zinc aluminum alloy ZA27 have been investigated. The results show that the number and distribution of pores are the key factors affecting the mechanical properties of ZA27. A slow solidification rate is beneficial to the ductility, while a rapid solidification rate improves the tensile strength of alloy basically. Among the modification agents RE, Sb Te, Sb Te RE and Sb Te Ti B, the addition of Sb Te to melt results in the best modified microstructure. The optimum pouring temperature for ZA27 is approximately 550?℃.展开更多
文摘Superfine composite powders of CeO2-ZrO2 (CZ) and CeO2-ZrO2-La2O3 (CZL) were prepared by hydrothermal method. The effects of pH?temperature and time for hydrothermal process on the performance of the resulting powders were studied. The optimized reaction parameters were on follows: the precursor′s pH≈9.0, hydrothermal temperature of 200 ℃ holding for 2 h. Thermal stable powders with average particle size smaller than 10 nm and specific surface area of 171 m2·g-1 were obtained. A BET specific surface area was still at 44 m2·g-1 after calcination at 1 000 ℃ for 6 hours.
文摘The crystal structure of {[Cd(sulfadiazine)2]n[Cd(sulfadiazine)2·H2O]n} (1) comprises of two different Cd centers in which sulfadiazine is used as a quadridentate and bidentate ligand to coordinate to Cd1 center, while it acts as a tridentate and bidentate ligand to bridge to Cd2 center, and the oxygen atom from water also coordinates to Cd2 center. As a result, the title compound bears two different 1D chain. CCDC: 274945.
文摘A novel one-dimensional coordination polymer, [Cd( μ-DPIA)2(H2O)]n (HDPIA=4,5-Diphenylimidazole-1-acetic acid), was synthesized and characterized by the element analysis, IR and single crystal X-ray diffraction. It crystallizes in the orthogonal space group Pca21 with unit cell parameters: a=1.509 6(3) nm, b=0.611 1(1) nm, c=3.216 4(6) nm, and V=2.967 1(10) nm3, Z=4, R=0.032 7, wR=0.086 7. The Cd atom is seven-coordinated by four O atoms and two N atoms from two chelating DPIA- ligands and one water molecule, and displays a distorted pentagonal bipyramid coordination geometry. Each DPIA- ligand bridges two adjacent Cd atoms, forming a infinite chain along the a axis direction. The Cd...Cd separation within the polymer is 0.765 0(3) nm. A layer structure which parallels to the ab plane is further constructed by hydrogen bonding interactions. CCDC: 254247.
文摘The effects of solidification rate, modifications and pouring temperature on the microstructure and mechanical properties of casting zinc aluminum alloy ZA27 have been investigated. The results show that the number and distribution of pores are the key factors affecting the mechanical properties of ZA27. A slow solidification rate is beneficial to the ductility, while a rapid solidification rate improves the tensile strength of alloy basically. Among the modification agents RE, Sb Te, Sb Te RE and Sb Te Ti B, the addition of Sb Te to melt results in the best modified microstructure. The optimum pouring temperature for ZA27 is approximately 550?℃.
