The adsorption of xenon from air has an interest in the monitoring of nuclear explosion or accident, or in the treatment of nuclear waste gas. In this paper, the pore structure of several series of activated carbon fi...The adsorption of xenon from air has an interest in the monitoring of nuclear explosion or accident, or in the treatment of nuclear waste gas. In this paper, the pore structure of several series of activated carbon fibers has been characterized. The adsorption properties of xenon on these activated carbon fibers under different temperatures have been studied in details. The results show that the xenon adsorption amount on activated carbon fibers do not increase with specific surface area of adsorbents, but are closely related to their pore size distribution. Pores whose radius equal to or narrow than 0.4nm would be more advantageous to the adsorption of xenon.展开更多
A series of sisal based activated carbon fibers were prepared with steam activation at temperature from 750℃ to 900℃. Their pore structures were characterized through their nitrogen adsorption isotherms at 77K using...A series of sisal based activated carbon fibers were prepared with steam activation at temperature from 750℃ to 900℃. Their pore structures were characterized through their nitrogen adsorption isotherms at 77K using different theories. The results showed that t-plot method and DR-plot method could suitably be used to characterize the mesopore structure and the multi-stage distribution of pore size of activated carbon fibers. It also showed that the pore size widens with the increase of activation temperature.展开更多
Structures of a series of activated carbon fibers were modified by impregnating them with organic and inorganic materials such as Methylene blue(Mb)、p-nitrophenol (PNP)、NaCl or by oxidizing with KMnO4 or HNO3. The i...Structures of a series of activated carbon fibers were modified by impregnating them with organic and inorganic materials such as Methylene blue(Mb)、p-nitrophenol (PNP)、NaCl or by oxidizing with KMnO4 or HNO3. The influence of pore filling or chemical treatment on their xenon adsorption properties was studied. The experimental results show that Mb and PNP filling of activated carbon fibers result in the decrease of xenon adsorption capacities of these treated ACFs, which is due to the decrease of their surface area and micro-pore volume. However, the adsorption capacity increases greatly with oxidizing treatment of activated carbon fibers by 7mol/L HNO3.展开更多
Experimental results showed that there are a few Xenon atom bubbles connected by the dislocation line in the UO2+x nuclear fuel, and the largest radius of bubbles is about 45 nm. This phenomenon is in contrast to trad...Experimental results showed that there are a few Xenon atom bubbles connected by the dislocation line in the UO2+x nuclear fuel, and the largest radius of bubbles is about 45 nm. This phenomenon is in contrast to traditional bubble formation mechanism. This phenomenon is very important in understanding the properties of nuclear fuel. In this work, we apply a time- dependent microscopic atom transport equation and take into account stress coherent potential in the boundary of the dislocation. Using the equation, we numerically solved the stress coherence effect and studied the transfer properties of Xenon atoms along the dislocation line. Our numerical results show that the transport of the Xenon atoms along the dislocation changes nonlinearly with the external driving energy, and reaches at the saturation values. It explains the growth limit of Xenon atom bubbles that is in agreement with the experiment results.展开更多
基金Natural Science Foundation Committee of Chinese government (grant No. 50073029) and by Guangdong Provincial Natural Science Foundation (001276)
文摘The adsorption of xenon from air has an interest in the monitoring of nuclear explosion or accident, or in the treatment of nuclear waste gas. In this paper, the pore structure of several series of activated carbon fibers has been characterized. The adsorption properties of xenon on these activated carbon fibers under different temperatures have been studied in details. The results show that the xenon adsorption amount on activated carbon fibers do not increase with specific surface area of adsorbents, but are closely related to their pore size distribution. Pores whose radius equal to or narrow than 0.4nm would be more advantageous to the adsorption of xenon.
基金Natural Science Foundation Committee of Chinese government (grant No. 50073029) and by Guangdong Provincial Natural Science Foundation (001276)
文摘A series of sisal based activated carbon fibers were prepared with steam activation at temperature from 750℃ to 900℃. Their pore structures were characterized through their nitrogen adsorption isotherms at 77K using different theories. The results showed that t-plot method and DR-plot method could suitably be used to characterize the mesopore structure and the multi-stage distribution of pore size of activated carbon fibers. It also showed that the pore size widens with the increase of activation temperature.
基金National Natural Science Foundation of China (50073029) and Guangdong Provincial Natural Science Foundation (001276)
文摘Structures of a series of activated carbon fibers were modified by impregnating them with organic and inorganic materials such as Methylene blue(Mb)、p-nitrophenol (PNP)、NaCl or by oxidizing with KMnO4 or HNO3. The influence of pore filling or chemical treatment on their xenon adsorption properties was studied. The experimental results show that Mb and PNP filling of activated carbon fibers result in the decrease of xenon adsorption capacities of these treated ACFs, which is due to the decrease of their surface area and micro-pore volume. However, the adsorption capacity increases greatly with oxidizing treatment of activated carbon fibers by 7mol/L HNO3.
基金financially supported by the Budget for Nuclear Research of the Ministryof Education,Culture,Sports,Science and Technology,based on the screening and counseling by the Atomic Energy Commission of Japan
文摘Experimental results showed that there are a few Xenon atom bubbles connected by the dislocation line in the UO2+x nuclear fuel, and the largest radius of bubbles is about 45 nm. This phenomenon is in contrast to traditional bubble formation mechanism. This phenomenon is very important in understanding the properties of nuclear fuel. In this work, we apply a time- dependent microscopic atom transport equation and take into account stress coherent potential in the boundary of the dislocation. Using the equation, we numerically solved the stress coherence effect and studied the transfer properties of Xenon atoms along the dislocation line. Our numerical results show that the transport of the Xenon atoms along the dislocation changes nonlinearly with the external driving energy, and reaches at the saturation values. It explains the growth limit of Xenon atom bubbles that is in agreement with the experiment results.
