This study was motivated by the world interest in the development of advanced processes of waste decomposition, due to the need of safer decomposition processes, particularly for the POPs (Persistent Organic Polluta...This study was motivated by the world interest in the development of advanced processes of waste decomposition, due to the need of safer decomposition processes, particularly for the POPs (Persistent Organic Pollutants) and the organochlorines. A tendency observed at several countries is the adoption of progressively more demanding legislation for the atmospheric emissions from the waste decomposition processes. The suitable final disposal of hazardous organic wastes such as PCBs (Polychlorinated Biphenyls), pesticides, herbicides and hospital residues constitutes a serious problem. In some point of their lifecycles, these wastes should be destroyed, in reason of the risk that they represent for the human being, animals and plants. The process involves a chemical reactor containing molten salts, such as sodium carbonate or some alkaline carbonates mixtures to decompose the organic waste. The decomposition is performed by submerged oxidation. Waste is injected below the surface of a turbulent salt bath along with the oxidizing agent. Decomposition of halogenated compounds, among which some pesticides, is particularly effective in molten salts. The process presents properties such as intrinsically safe control of organochlorine emissions. This work describes the process developed at IPEN/CNEN-SP (Nuclear and Energetic Research Institute/Brazilian Nuclear Energy Commission) for complete thermal decomposition of hazardous wastes through oxidation submerged in molten salts.展开更多
In this paper, an FEM (Finite Element Method) model is established for the main span of the bridge, with the main box arch and suspender members modeled by beam elements, truss members by truss elements, and the ort...In this paper, an FEM (Finite Element Method) model is established for the main span of the bridge, with the main box arch and suspender members modeled by beam elements, truss members by truss elements, and the orthotropic steel deck by plate elements. The natural frequencies and mode shapes are acquired by the eigen-parameter analysis. By input of a typical earthquake excitation to the bridge system, the dynamic responses of the bridge, including the displacement and accelerations of the main joints of the structure, and the seismic forces and stresses of the key members, are calculated by the structural analysis program, based on which the main laws of the seismic responses of the bridge are summarized, and the safety of the structure is evaluated.展开更多
The authors study the asymptotic behaviour of solutions of the heat equation and a number of evolution equations using scaling techniques. It is proved that in the framework of bounded data stabilization need not occu...The authors study the asymptotic behaviour of solutions of the heat equation and a number of evolution equations using scaling techniques. It is proved that in the framework of bounded data stabilization need not occur and the general asymptotic behaviour is complex. This behaviour reflects for large times, even on compact sets, the complexity of the initial data at infinity.展开更多
This paper investigates periodic boundary value problem for first order nonlinear impulsive integro-differelltial equations of mixed type in a Banach space. By establishing a comparison result, criteria on the existen...This paper investigates periodic boundary value problem for first order nonlinear impulsive integro-differelltial equations of mixed type in a Banach space. By establishing a comparison result, criteria on the existence of maximal and minimal solutions are obtained.展开更多
文摘This study was motivated by the world interest in the development of advanced processes of waste decomposition, due to the need of safer decomposition processes, particularly for the POPs (Persistent Organic Pollutants) and the organochlorines. A tendency observed at several countries is the adoption of progressively more demanding legislation for the atmospheric emissions from the waste decomposition processes. The suitable final disposal of hazardous organic wastes such as PCBs (Polychlorinated Biphenyls), pesticides, herbicides and hospital residues constitutes a serious problem. In some point of their lifecycles, these wastes should be destroyed, in reason of the risk that they represent for the human being, animals and plants. The process involves a chemical reactor containing molten salts, such as sodium carbonate or some alkaline carbonates mixtures to decompose the organic waste. The decomposition is performed by submerged oxidation. Waste is injected below the surface of a turbulent salt bath along with the oxidizing agent. Decomposition of halogenated compounds, among which some pesticides, is particularly effective in molten salts. The process presents properties such as intrinsically safe control of organochlorine emissions. This work describes the process developed at IPEN/CNEN-SP (Nuclear and Energetic Research Institute/Brazilian Nuclear Energy Commission) for complete thermal decomposition of hazardous wastes through oxidation submerged in molten salts.
基金Acknowledgments: This study is sponsored by the Natural Science Foundation of China (No. 90715008) and the Flander (Belgium)-China Bilateral Project (No. BIL07/07).
文摘In this paper, an FEM (Finite Element Method) model is established for the main span of the bridge, with the main box arch and suspender members modeled by beam elements, truss members by truss elements, and the orthotropic steel deck by plate elements. The natural frequencies and mode shapes are acquired by the eigen-parameter analysis. By input of a typical earthquake excitation to the bridge system, the dynamic responses of the bridge, including the displacement and accelerations of the main joints of the structure, and the seismic forces and stresses of the key members, are calculated by the structural analysis program, based on which the main laws of the seismic responses of the bridge are summarized, and the safety of the structure is evaluated.
文摘The authors study the asymptotic behaviour of solutions of the heat equation and a number of evolution equations using scaling techniques. It is proved that in the framework of bounded data stabilization need not occur and the general asymptotic behaviour is complex. This behaviour reflects for large times, even on compact sets, the complexity of the initial data at infinity.
文摘This paper investigates periodic boundary value problem for first order nonlinear impulsive integro-differelltial equations of mixed type in a Banach space. By establishing a comparison result, criteria on the existence of maximal and minimal solutions are obtained.