This paper studied the basic properties of saline soil at different depths of a sampling site in Da＇an, China, through field reconnaissance and laboratory analysis. A series of experiments which comprised the analyse...This paper studied the basic properties of saline soil at different depths of a sampling site in Da＇an, China, through field reconnaissance and laboratory analysis. A series of experiments which comprised the analyses of grain size distribution, mineral composition, soil physical properties, soluble salt concent, pH, organic content and cation exchange capacity were conducted. Through these experiments, the distribution rule of each property and their causes are discussed. These results could provide a fundamental base for the study of moisture migration.展开更多
Basicity of ZrO2 is enhanced by KF modification due to the reaction of KF with ZrO2 surface: KF+ ZrO2-> K2ZrF6 + KOH. After pretreated above 673K, KF/ZrO2 catalyst exhibited higher activity for 1-butene isomerizati...Basicity of ZrO2 is enhanced by KF modification due to the reaction of KF with ZrO2 surface: KF+ ZrO2-> K2ZrF6 + KOH. After pretreated above 673K, KF/ZrO2 catalyst exhibited higher activity for 1-butene isomerization at 273K than ZrO2. The amount of basic sites strongly adsorbing CO2 in the form of bicarbonate was also increased.展开更多
Radioactive wastes arising from a wide range of human activities are in many different physical and chemical forms, contaminated with varying radioactivity. Their common features are the potential hazard associated wi...Radioactive wastes arising from a wide range of human activities are in many different physical and chemical forms, contaminated with varying radioactivity. Their common features are the potential hazard associated with their radioactivity and the need to manage them in such a way as to protect the human environment. The geological disposal is regarded as the most reasonable and effective way to safely disposing high-level radioactive wastes in the world. The conceptual model of geological disposal in China is based on a multi-barrier system that combines an isolating geological environment with an engineered barrier system. The buffer is one of the main engineered barriers for HLW repository. It is expected to maintain its low water permeability, self-sealing property, radio nuclides adsorption and retardation properties, thermal conductivity, chemical buffering property, canister supporting property, and stress buffering property over a long period of time. Bentonite is selected as the main content of buffer material that can satisfy the above requirements. The Gaomiaozi deposit is selected as the candidate supplier for China＇s buffer material of high level radioactive waste repository. This paper presents the geological features of the GMZ deposit and basic properties of the GMZ Na-bentonite. It is a super-large deposit with a high content of montmorillonite （about 75 %）, and GMZ-1, which is Na-bentonite produced from GMZ deposit is selected as the reference material for China＇s buffer material study.展开更多
The basic high-temperature properties of iron ore play a crucial role in optimizing sintering and ore blending,but the testing process for these properties is complex and has significant lag time,which cannot meet the...The basic high-temperature properties of iron ore play a crucial role in optimizing sintering and ore blending,but the testing process for these properties is complex and has significant lag time,which cannot meet the actual needs of ore blending.A prediction model for the basic high-temperature properties of iron ore fines was thus proposed based on a combination of machine learning algorithms and genetic algorithms.First,the prediction accuracy of different machine learning models for the basic high-temperature properties of iron ore fines was compared.Then,a random forest model optimized by genetic algorithms was built,further improving the prediction accuracy of the model.The test results show that the random forest model optimized by genetic algorithms has the highest prediction accuracy for the lowest assimilation temperature and liquid phase fluidity of iron ore,with a determination coefficient of 0.903 for the lowest assimilation temperature and 0.927 for the liquid phase fluidity after optimization.The trained model meets the fluctuation requirements of on-site testing and has been successfully applied to actual production on site.展开更多
We gived the definition of Hom-Leibniz superalgebra and studied its basic properties. In particular, the derivations of Hom-Leibniz Superalgebras are portrayed in detail.
Low-temperature selective catalytic reduction(SCR)is important for the elimination of NOfrom stationary sources.In the present study,the loading of Ce and W onα-Fe_(2)O_(3)was achieved through the integration of sing...Low-temperature selective catalytic reduction(SCR)is important for the elimination of NOfrom stationary sources.In the present study,the loading of Ce and W onα-Fe_(2)O_(3)was achieved through the integration of single-mode microwave and incipient wetness impregnation(IWI)methods.The scanning electron microscopy(SEM)and transmission electron microscopy(TEM)images reveal that the structure ofα-Fe_(2)O_(3)is spindle-like,and the structure remains unchanged after the introduction of Ce and/or W.The results of NH-SCR investigation demonstrate that NOconversion over Ce-W/α-Fe_(2)O_(3)is more than85%at 300℃,which is much higher than that over Ce/a-Fe_(2)O_(3)andα-Fe_(2)O_(3),Our studies illustrate that the addition of Ce can significantly increase the amount of surface oxygen vacancies as well as sites of moderate basicity.On the other hand,the addition of W can obviously decrease the amount of basic sites and increase the number of Br?nsted acid sites.The synergistic effect of Ce and W addition on balancing acidity/basicity properties accounts for the high activity of CeW/α-Fe_(2)O_(3)for NOremoval at low temperatures.The study provides insight into the relationship between acidity/basicity properties and catalytic performance of Ce-W/α-Fe_(2)O_(3)catalysts,which is beneficial to the design of high-performance NH-SCR catalyst for NOremoval at low temperatures.展开更多
基金supported by the National Natural Science Foundation of China(Nos.41430642 and 41372267)the Research Fund for the Doctoral Program of Higher Education of China(No.20120061110054)
文摘This paper studied the basic properties of saline soil at different depths of a sampling site in Da＇an, China, through field reconnaissance and laboratory analysis. A series of experiments which comprised the analyses of grain size distribution, mineral composition, soil physical properties, soluble salt concent, pH, organic content and cation exchange capacity were conducted. Through these experiments, the distribution rule of each property and their causes are discussed. These results could provide a fundamental base for the study of moisture migration.
文摘Basicity of ZrO2 is enhanced by KF modification due to the reaction of KF with ZrO2 surface: KF+ ZrO2-> K2ZrF6 + KOH. After pretreated above 673K, KF/ZrO2 catalyst exhibited higher activity for 1-butene isomerization at 273K than ZrO2. The amount of basic sites strongly adsorbing CO2 in the form of bicarbonate was also increased.
文摘Radioactive wastes arising from a wide range of human activities are in many different physical and chemical forms, contaminated with varying radioactivity. Their common features are the potential hazard associated with their radioactivity and the need to manage them in such a way as to protect the human environment. The geological disposal is regarded as the most reasonable and effective way to safely disposing high-level radioactive wastes in the world. The conceptual model of geological disposal in China is based on a multi-barrier system that combines an isolating geological environment with an engineered barrier system. The buffer is one of the main engineered barriers for HLW repository. It is expected to maintain its low water permeability, self-sealing property, radio nuclides adsorption and retardation properties, thermal conductivity, chemical buffering property, canister supporting property, and stress buffering property over a long period of time. Bentonite is selected as the main content of buffer material that can satisfy the above requirements. The Gaomiaozi deposit is selected as the candidate supplier for China＇s buffer material of high level radioactive waste repository. This paper presents the geological features of the GMZ deposit and basic properties of the GMZ Na-bentonite. It is a super-large deposit with a high content of montmorillonite （about 75 %）, and GMZ-1, which is Na-bentonite produced from GMZ deposit is selected as the reference material for China＇s buffer material study.
基金the National Natural Science Foundation of China(52204335)the Cross-disciplinary Research Project for Young Teachers of the University of Science and Technology Beijing(FRF-IDRY-22-004).
文摘The basic high-temperature properties of iron ore play a crucial role in optimizing sintering and ore blending,but the testing process for these properties is complex and has significant lag time,which cannot meet the actual needs of ore blending.A prediction model for the basic high-temperature properties of iron ore fines was thus proposed based on a combination of machine learning algorithms and genetic algorithms.First,the prediction accuracy of different machine learning models for the basic high-temperature properties of iron ore fines was compared.Then,a random forest model optimized by genetic algorithms was built,further improving the prediction accuracy of the model.The test results show that the random forest model optimized by genetic algorithms has the highest prediction accuracy for the lowest assimilation temperature and liquid phase fluidity of iron ore,with a determination coefficient of 0.903 for the lowest assimilation temperature and 0.927 for the liquid phase fluidity after optimization.The trained model meets the fluctuation requirements of on-site testing and has been successfully applied to actual production on site.
基金Supported by the National Natural Science Foundation of China（10871057, 11171055）
文摘We gived the definition of Hom-Leibniz superalgebra and studied its basic properties. In particular, the derivations of Hom-Leibniz Superalgebras are portrayed in detail.
基金Project supported by the National Natural Science Foundation of China(21703037,22108037)the Natural Science Foundation of Fujian(2018J10691)。
文摘Low-temperature selective catalytic reduction(SCR)is important for the elimination of NOfrom stationary sources.In the present study,the loading of Ce and W onα-Fe_(2)O_(3)was achieved through the integration of single-mode microwave and incipient wetness impregnation(IWI)methods.The scanning electron microscopy(SEM)and transmission electron microscopy(TEM)images reveal that the structure ofα-Fe_(2)O_(3)is spindle-like,and the structure remains unchanged after the introduction of Ce and/or W.The results of NH-SCR investigation demonstrate that NOconversion over Ce-W/α-Fe_(2)O_(3)is more than85%at 300℃,which is much higher than that over Ce/a-Fe_(2)O_(3)andα-Fe_(2)O_(3),Our studies illustrate that the addition of Ce can significantly increase the amount of surface oxygen vacancies as well as sites of moderate basicity.On the other hand,the addition of W can obviously decrease the amount of basic sites and increase the number of Br?nsted acid sites.The synergistic effect of Ce and W addition on balancing acidity/basicity properties accounts for the high activity of CeW/α-Fe_(2)O_(3)for NOremoval at low temperatures.The study provides insight into the relationship between acidity/basicity properties and catalytic performance of Ce-W/α-Fe_(2)O_(3)catalysts,which is beneficial to the design of high-performance NH-SCR catalyst for NOremoval at low temperatures.
