Ba 3Zn Z Co 2 Z Fe 24 O 41 /SiO 2 ( Z varies from 0.0 to 1.2 in step of 0.4) microcrystalline glass ceramics were prepared by citrate sol gel process at 1 200 ℃ in the system of BaO Fe 2O 3 CoO ZnO SiO 2. The samples...Ba 3Zn Z Co 2 Z Fe 24 O 41 /SiO 2 ( Z varies from 0.0 to 1.2 in step of 0.4) microcrystalline glass ceramics were prepared by citrate sol gel process at 1 200 ℃ in the system of BaO Fe 2O 3 CoO ZnO SiO 2. The samples were characterized by X ray diffraction (XRD) and scanning electron microscopy (SEM). The complex dielectric constant and complex permeability of Ba 3Zn Z Co 2 Z Fe 24 O 41 /SiO 2 microcrystalline glass ceramics were measured in the range of 0.16.0 GHz by transmissioneflection coaxial line method. The natural resonance phenomenon was observed in μ ″ spectra for all the Ba 3Zn Z Co 2 Z Fe 24 O 41 /SiO 2 microcrystalline glass ceramics, which was closely affected by the substitution of Zn 2+ ion.展开更多
利用三步法(热溶剂还原法,硅烷化和氨基功能化)制备了Fe3O4@SiO2-NH2磁性纳米复合材料用于水体中全氟化合物的萃取,结合超高效液相色谱-串联三重四极杆质谱(UPLC-MS/MS)技术,建立了水体中7种典型全氟化合物的检测方法。通过扫描电镜...利用三步法(热溶剂还原法,硅烷化和氨基功能化)制备了Fe3O4@SiO2-NH2磁性纳米复合材料用于水体中全氟化合物的萃取,结合超高效液相色谱-串联三重四极杆质谱(UPLC-MS/MS)技术,建立了水体中7种典型全氟化合物的检测方法。通过扫描电镜(SEM)、透射电镜(TEM)和傅立叶红外光谱(FT-IR)等手段对材料进行表征,详细研究了解析溶剂、解析溶剂体积、解析时间、吸附时间和p H值等因素对萃取效率的影响。结果表明:氨基被成功修饰在Fe3O4@SiO2纳米粒子的表面,Fe3O4@SiO2-NH2磁性纳米材料对目标全氟化合物有较好的萃取效果,在萃取时间为20 min,解析溶剂为3 m L×4含0.28%氨水的甲醇,解析时间为5 min,p H 5.0时,萃取效率最佳。在最优实验条件下,全氟化合物的检出限为0.2~0.5 ng/L,线性范围为1~500 ng/L。方法用于实际水体中目标全氟化合物的检测,样品的加标回收率不低于82.0%。展开更多
A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly conce...A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other phases.The distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were investigated.The results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid solution.The distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid solution.The distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of Fe.An increase in the FeO content in slag brought a higher P2O5 content in the solid solution.As slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased.展开更多
Attempts had been made to synthesize Al2O3-2SiO2 nanopowders by sol-gel method with tetraethoxysilane(TEOS) and aluminum nitrate(ANN) as the starting materials.DTS,TEM,SEM and BET were employed to study the effect...Attempts had been made to synthesize Al2O3-2SiO2 nanopowders by sol-gel method with tetraethoxysilane(TEOS) and aluminum nitrate(ANN) as the starting materials.DTS,TEM,SEM and BET were employed to study the effects of process parameters on the size,specific surface area and structure(morphology) of powders.The alkali-activation reactivity of the powders was tested for manufacturing geopolymers and their hydrothermal reactions were performed for fabricating zeolites.The results show that the optimum process parameters and drying method for preparing Al2O3-2SiO2 nanopowders are as follows:the molar ratio of water and ethanol to TEOS are 0:1 and 12:1 respectively at synthetic temperature of 50 ℃ and the drying method is azeotropic distillation with microwave drying.The average particle diameters of the powders were about 70 nm and the largest BET specific surface area was up to 669 m^2·g^-1.The compressive strength of the geopolymer and the calcium exchange capacity(by CaCO3) of NaA zeolite prepared with the powders reached to 29 MPa and 366 m^2·g^-1 respectively.展开更多
摘要Ba 3Zn Z Co 2 Z Fe 24 O 41 /SiO 2 ( Z varies from 0.0 to 1.2 in step of 0.4) microcrystalline glass ceramics were prepared by citrate sol gel process at 1 200 ℃ in the system of BaO Fe 2O 3 CoO ZnO SiO 2. The samples were characterized by X ray diffraction (XRD) and scanning electron microscopy (SEM). The complex dielectric constant and complex permeability of Ba 3Zn Z Co 2 Z Fe 24 O 41 /SiO 2 microcrystalline glass ceramics were measured in the range of 0.16.0 GHz by transmissioneflection coaxial line method. The natural resonance phenomenon was observed in μ ″ spectra for all the Ba 3Zn Z Co 2 Z Fe 24 O 41 /SiO 2 microcrystalline glass ceramics, which was closely affected by the substitution of Zn 2+ ion.
摘要利用三步法(热溶剂还原法,硅烷化和氨基功能化)制备了Fe3O4@SiO2-NH2磁性纳米复合材料用于水体中全氟化合物的萃取,结合超高效液相色谱-串联三重四极杆质谱(UPLC-MS/MS)技术,建立了水体中7种典型全氟化合物的检测方法。通过扫描电镜(SEM)、透射电镜(TEM)和傅立叶红外光谱(FT-IR)等手段对材料进行表征,详细研究了解析溶剂、解析溶剂体积、解析时间、吸附时间和p H值等因素对萃取效率的影响。结果表明:氨基被成功修饰在Fe3O4@SiO2纳米粒子的表面,Fe3O4@SiO2-NH2磁性纳米材料对目标全氟化合物有较好的萃取效果,在萃取时间为20 min,解析溶剂为3 m L×4含0.28%氨水的甲醇,解析时间为5 min,p H 5.0时,萃取效率最佳。在最优实验条件下,全氟化合物的检出限为0.2~0.5 ng/L,线性范围为1~500 ng/L。方法用于实际水体中目标全氟化合物的检测,样品的加标回收率不低于82.0%。
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51704010,51604003,U1760117)Key Laboratory Open Project Fund of Metallurgical Emission Reduction and Resources Recycling(Anhui University of Technology)Ministry of Education(JKF18-02).
摘要A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other phases.The distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were investigated.The results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid solution.The distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid solution.The distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of Fe.An increase in the FeO content in slag brought a higher P2O5 content in the solid solution.As slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased.
基金Supported by the National Natural Science Foundation of China (50962002,50602006)Opening Funds of State Key Laboratory of Chemical Resource Engineering of Beijing University of Chemical Technology (201008)
摘要Attempts had been made to synthesize Al2O3-2SiO2 nanopowders by sol-gel method with tetraethoxysilane(TEOS) and aluminum nitrate(ANN) as the starting materials.DTS,TEM,SEM and BET were employed to study the effects of process parameters on the size,specific surface area and structure(morphology) of powders.The alkali-activation reactivity of the powders was tested for manufacturing geopolymers and their hydrothermal reactions were performed for fabricating zeolites.The results show that the optimum process parameters and drying method for preparing Al2O3-2SiO2 nanopowders are as follows:the molar ratio of water and ethanol to TEOS are 0:1 and 12:1 respectively at synthetic temperature of 50 ℃ and the drying method is azeotropic distillation with microwave drying.The average particle diameters of the powders were about 70 nm and the largest BET specific surface area was up to 669 m^2·g^-1.The compressive strength of the geopolymer and the calcium exchange capacity(by CaCO3) of NaA zeolite prepared with the powders reached to 29 MPa and 366 m^2·g^-1 respectively.