Oily cold rolling mill （CRM） sludge is one of the pollutants emitted by iron and steel plants. Recycling oily CRM sludge can not only reduce pollution but also bring social and environmental benefits. In this study,...Oily cold rolling mill （CRM） sludge is one of the pollutants emitted by iron and steel plants. Recycling oily CRM sludge can not only reduce pollution but also bring social and environmental benefits. In this study, using oily CRM sludge as sources of iron oxide, the strontium ferrite powders were synthesized in multiple steps including vacuum distillation, magnetic separation, oxidizing roasting, and solidstate reaction. The optimal technological conditions of vacuum distillation and oxidizing roasting were studied carefully. To consider the effects of Fe203/ SrCO3 tool ratio, calcination temperature, milling time and calcination time on magnetic properties of prepared strontium ferrite powders, the orthogonal experimental method was adopted. The maximum saturation magneti- zation （62.6 mA-m2.g-1） of the synthesized strontium ferrite powders was achieved at the Fe203/SrCO3 mol ratio of 6, 5 h milling time, 1250 ~C calcination temperature, and 1 h calcination time. Strontium ferrite powders syn- thesis method not only provides a cheap, high quality raw material for the production of strontium ferrite powders, but also effectively prevents the environmental pollution.展开更多
A precursor of BaCe0.5Zr0.4Y0. 1O3-α electrolytes was synthesized by the sol-gel method and sintered at temperature which were 150 - 250 ℃ lower than by solid state reaction. The AC impedance spectrums of electrolyt...A precursor of BaCe0.5Zr0.4Y0. 1O3-α electrolytes was synthesized by the sol-gel method and sintered at temperature which were 150 - 250 ℃ lower than by solid state reaction. The AC impedance spectrums of electrolytes were measured by AUTOLAB PGSTA30 electrochemical measuring device at different temperatures. The conductivities of the electrolytes are 1.62×10^-4 - 6.43×10^-3, 2.52×10^-5 - 3.73×10^-3S·cm^-1 in the temperature range of 350-800℃. The activity energies are 0.54 and 0.84 eV. At the same time BaCe0.9Y0.1O3-α was prepared by direct solid state reaction. The conductivity of BaCe0.9Y0.1O3-α is 1 × 10^-4- 4×10^-3 S·cm^-1 and the activation energy is 0.50 eV at the same condition. The results show that conduction of electrolyte prepared by sol-gel method is higher than the one by solid state reaction. As far as BaCe0.9Y0.1O3-α concerned, its conductivity of the Zr-substituted specimens is decreased.展开更多
In order to reveal the reactivity of a functional group in an aromatic compound having two substituents inthe aromatic ring, the hydrogen-isotope exchange reaction (T-H exchange reaction) between tritiated water vapor...In order to reveal the reactivity of a functional group in an aromatic compound having two substituents inthe aromatic ring, the hydrogen-isotope exchange reaction (T-H exchange reaction) between tritiated water vapor(HTO vapor) and 4-amino-2-methylbenzenesulfonic acid (and 5-amino-2-methylphenol) were dynamically observedat 50 (and 70 ) in a gas ℃ ℃ -solid system. Consequently, the fact that the specific activity of the acid increased withtime was obtained, and the T-for-H exchange reaction occurred. By applying the A"-McKay plot method to the dataobserved, the rate constant of each functional group for the reaction was obtained. After the additive property of theHammett’s rule was applied to this work, the new substituent constants were obtained. From the above-mentioned,the following four items have been confirmed: (1) the reactivity of the functional groups can be dynamically analyzed,and the A"-McKay plot method is useful to analyze the reactivity; (2) the additive property of the Hammett’s rule isapplicable to quantitative comparison of the reactivity of the functional groups; (3) the reactivity of the functionalgroups can be simultaneously analyzed by using the A"-McKay plot method in the T-H exchange reaction; and (4) themethod used in this work is also useful for analyzing the reactivity of a certain material having some kinds of functional groups.展开更多
基金supported by the National Key Technology R&D Program (Nos. 2012BAC02B01, 2012BAC12B05, 2011BAE13B07, and 2011BAC10B02)the National High Technology Research and Development Program of China (No. 2012AA063202)+2 种基金the National Natural Science Foundation of China (Nos. 51174247 and 51004011)the Science and Technology Program of Guangdong Province, China (No. 2010A030200003)the Ph.D. Programs Foundation of the Ministry of Education of China (No. 2010000612003)
文摘Oily cold rolling mill （CRM） sludge is one of the pollutants emitted by iron and steel plants. Recycling oily CRM sludge can not only reduce pollution but also bring social and environmental benefits. In this study, using oily CRM sludge as sources of iron oxide, the strontium ferrite powders were synthesized in multiple steps including vacuum distillation, magnetic separation, oxidizing roasting, and solidstate reaction. The optimal technological conditions of vacuum distillation and oxidizing roasting were studied carefully. To consider the effects of Fe203/ SrCO3 tool ratio, calcination temperature, milling time and calcination time on magnetic properties of prepared strontium ferrite powders, the orthogonal experimental method was adopted. The maximum saturation magneti- zation （62.6 mA-m2.g-1） of the synthesized strontium ferrite powders was achieved at the Fe203/SrCO3 mol ratio of 6, 5 h milling time, 1250 ~C calcination temperature, and 1 h calcination time. Strontium ferrite powders syn- thesis method not only provides a cheap, high quality raw material for the production of strontium ferrite powders, but also effectively prevents the environmental pollution.
文摘A precursor of BaCe0.5Zr0.4Y0. 1O3-α electrolytes was synthesized by the sol-gel method and sintered at temperature which were 150 - 250 ℃ lower than by solid state reaction. The AC impedance spectrums of electrolytes were measured by AUTOLAB PGSTA30 electrochemical measuring device at different temperatures. The conductivities of the electrolytes are 1.62×10^-4 - 6.43×10^-3, 2.52×10^-5 - 3.73×10^-3S·cm^-1 in the temperature range of 350-800℃. The activity energies are 0.54 and 0.84 eV. At the same time BaCe0.9Y0.1O3-α was prepared by direct solid state reaction. The conductivity of BaCe0.9Y0.1O3-α is 1 × 10^-4- 4×10^-3 S·cm^-1 and the activation energy is 0.50 eV at the same condition. The results show that conduction of electrolyte prepared by sol-gel method is higher than the one by solid state reaction. As far as BaCe0.9Y0.1O3-α concerned, its conductivity of the Zr-substituted specimens is decreased.
文摘In order to reveal the reactivity of a functional group in an aromatic compound having two substituents inthe aromatic ring, the hydrogen-isotope exchange reaction (T-H exchange reaction) between tritiated water vapor(HTO vapor) and 4-amino-2-methylbenzenesulfonic acid (and 5-amino-2-methylphenol) were dynamically observedat 50 (and 70 ) in a gas ℃ ℃ -solid system. Consequently, the fact that the specific activity of the acid increased withtime was obtained, and the T-for-H exchange reaction occurred. By applying the A"-McKay plot method to the dataobserved, the rate constant of each functional group for the reaction was obtained. After the additive property of theHammett’s rule was applied to this work, the new substituent constants were obtained. From the above-mentioned,the following four items have been confirmed: (1) the reactivity of the functional groups can be dynamically analyzed,and the A"-McKay plot method is useful to analyze the reactivity; (2) the additive property of the Hammett’s rule isapplicable to quantitative comparison of the reactivity of the functional groups; (3) the reactivity of the functionalgroups can be simultaneously analyzed by using the A"-McKay plot method in the T-H exchange reaction; and (4) themethod used in this work is also useful for analyzing the reactivity of a certain material having some kinds of functional groups.
