The total macroscopic removal cross sections,deposited energies and the absorbed doses of three new shielding composites loaded with specific boron-rich slag,boron concentrate ore and boron mud of China for 252Cf neut...The total macroscopic removal cross sections,deposited energies and the absorbed doses of three new shielding composites loaded with specific boron-rich slag,boron concentrate ore and boron mud of China for 252Cf neutron source were investigated by experimental and Monte Carlo calculation.The results were evaluated by boron mole numbers per unit volume in composites.The half value layers of the composites were calculated and compared with that of Portland concrete,indicating that ascending boron mole numbers per unit volume in the composites can enhance the shielding properties of the composites for 252Cf neutron source.展开更多
Characteristic and hydrometallurgy processes for Baotou mixed-type rare earth concentrate, bastnasite, and ionic adsorption deposit in China were reviewed. The R ＆ D circumstance and new progresses in extraction and ...Characteristic and hydrometallurgy processes for Baotou mixed-type rare earth concentrate, bastnasite, and ionic adsorption deposit in China were reviewed. The R ＆ D circumstance and new progresses in extraction and separation of RE element in China were introduced. Moreover, the development trend of RE hydrometallurgy was predicted. The direction and emphasised fields of research and development are also brought forward as： to R ＆ D high efficient green progresses in hydrometallurgy and separation of RE ore, resolve the waste pollution problem of water, slagand gas, reduce the chemical material consumption and improve comprehensive efficiency of resources; to R ＆ D preparation technology for RE compounds with ultra high-purity and special physical property for extending application fields of RE.展开更多
Kinetics of photocatalytic degradation of methylene blue(MB) over Ca Ti O3 was studied. Effects of the solution p H, the MB concentration, the Ca Ti O3 dosage, and the type of light source on photocatalytic degradatio...Kinetics of photocatalytic degradation of methylene blue(MB) over Ca Ti O3 was studied. Effects of the solution p H, the MB concentration, the Ca Ti O3 dosage, and the type of light source on photocatalytic degradation rate of MB over Ca Ti O3 were investigated in detail. The results show that photocatalytic degradation of MB over Ca Ti O3 followed the first-order reaction. The apparent rate constant(kobs) of MB significantly increased with increasing solution p H while it greatly decreased with increasing MB concentration. The kobs of MB increased with increasing Ca Ti O3 dosage from 0.05 to 0.1 g, whereas it slightly decreased with increasing Ca Ti O3 dosage in the range of 0.1-0.4 g. The kobs of MB under UV-visible light irradiation was larger by factors of 2.2 than that under visible light irradiation. The kobs of MB was(4.8±0.3)×10-1h-1 under optimal conditions with the solution p H of 11, the MB concentration of 1 ppm, the Ca Ti O3 dosage of 0.1 g, and UV-visible light irradiation.展开更多
The sintering of chromium-containing vanadium-titanium magnetite using different coke contents was studied through the sintering pot tests, X-ray diffraction analysis and mineralogical phase analysis. Results showed t...The sintering of chromium-containing vanadium-titanium magnetite using different coke contents was studied through the sintering pot tests, X-ray diffraction analysis and mineralogical phase analysis. Results showed that, as the coke content increased from 3.2% to 4.4%, the liquid phase and combustion zone thickness increased while the vertical sintering rate and ratio of sintered product decreased. In addition, the combustion ratio of exhaust gas also increased with increasing the coke content, indicating that combustion zone temperature also increased, and the excessive the coke content in the sintering process of vanadiumtitanium magnetite is harmful. As the coke content increased, the magnetite, silicates, and perovskite contents of the sintered ore increased while the contents of hematite and calcium ferrite of sintered ore decreased; drum strength decreased, and reduction degradation properties increased while reduction ability decreased. We found that the appropriate coke content for the sintering process is 3.6 wt%.展开更多
基金Supported by National Natural Science Foundation of China(Grant Number:50774022)
文摘The total macroscopic removal cross sections,deposited energies and the absorbed doses of three new shielding composites loaded with specific boron-rich slag,boron concentrate ore and boron mud of China for 252Cf neutron source were investigated by experimental and Monte Carlo calculation.The results were evaluated by boron mole numbers per unit volume in composites.The half value layers of the composites were calculated and compared with that of Portland concrete,indicating that ascending boron mole numbers per unit volume in the composites can enhance the shielding properties of the composites for 252Cf neutron source.
文摘Characteristic and hydrometallurgy processes for Baotou mixed-type rare earth concentrate, bastnasite, and ionic adsorption deposit in China were reviewed. The R ＆ D circumstance and new progresses in extraction and separation of RE element in China were introduced. Moreover, the development trend of RE hydrometallurgy was predicted. The direction and emphasised fields of research and development are also brought forward as： to R ＆ D high efficient green progresses in hydrometallurgy and separation of RE ore, resolve the waste pollution problem of water, slagand gas, reduce the chemical material consumption and improve comprehensive efficiency of resources; to R ＆ D preparation technology for RE compounds with ultra high-purity and special physical property for extending application fields of RE.
基金Funded by the National Natural Science Foundation of China(No.21407020)the Fundamental Research Fund for the Central Universities(No.N130302004)
文摘Kinetics of photocatalytic degradation of methylene blue(MB) over Ca Ti O3 was studied. Effects of the solution p H, the MB concentration, the Ca Ti O3 dosage, and the type of light source on photocatalytic degradation rate of MB over Ca Ti O3 were investigated in detail. The results show that photocatalytic degradation of MB over Ca Ti O3 followed the first-order reaction. The apparent rate constant(kobs) of MB significantly increased with increasing solution p H while it greatly decreased with increasing MB concentration. The kobs of MB increased with increasing Ca Ti O3 dosage from 0.05 to 0.1 g, whereas it slightly decreased with increasing Ca Ti O3 dosage in the range of 0.1-0.4 g. The kobs of MB under UV-visible light irradiation was larger by factors of 2.2 than that under visible light irradiation. The kobs of MB was(4.8±0.3)×10-1h-1 under optimal conditions with the solution p H of 11, the MB concentration of 1 ppm, the Ca Ti O3 dosage of 0.1 g, and UV-visible light irradiation.
基金Funded by the National Natural Science Foundation of China(Nos.51604065,51674084)the Fundamental Funds for the Program of the Science Foundation of Liaoning Province(No.20170540316)
文摘The sintering of chromium-containing vanadium-titanium magnetite using different coke contents was studied through the sintering pot tests, X-ray diffraction analysis and mineralogical phase analysis. Results showed that, as the coke content increased from 3.2% to 4.4%, the liquid phase and combustion zone thickness increased while the vertical sintering rate and ratio of sintered product decreased. In addition, the combustion ratio of exhaust gas also increased with increasing the coke content, indicating that combustion zone temperature also increased, and the excessive the coke content in the sintering process of vanadiumtitanium magnetite is harmful. As the coke content increased, the magnetite, silicates, and perovskite contents of the sintered ore increased while the contents of hematite and calcium ferrite of sintered ore decreased; drum strength decreased, and reduction degradation properties increased while reduction ability decreased. We found that the appropriate coke content for the sintering process is 3.6 wt%.
