Using the fundamental adsorption equilibrium and kinetic parameters obtained from batch experiments, the mass transport and hydrodynamic behavior in the expanded bed of DEAE Spherodex M was analyzed with the breakthro...Using the fundamental adsorption equilibrium and kinetic parameters obtained from batch experiments, the mass transport and hydrodynamic behavior in the expanded bed of DEAE Spherodex M was analyzed with the breakthrough model. The results showed that the effect of particle size on breakthrough behavior was obviously greater than that of other parameters.The change of the time of 5% breakthrough, with increasing and decreasing mean particle diameter by a factor of 2, reached about 40% relative to that with the mean diameter, 88 μm. Secondary effects on expanded bed adsorption were film mass transfer and pore diffusion (<10%). Axial dispersion in solid phase had almost negligible effect on the adsorption process. Therefore, the assumption of even dispersion of adsorbent within the expanded bed may result in the model discrepancy to a great extent. It is considered that the breakthrough model can be further improved by taking into account particle size distribution in the expanded bed.展开更多
考虑到城市环境中障碍物对网络性能的重要影响,在NS2(Network Simulator version 2)中加入了代表障碍物的概率穿透模型,使仿真环境更接近真实环境。针对AODV(Ad hoc On-Demand Distance Vector Routing)协议应用在城市场景下的缺陷,提...考虑到城市环境中障碍物对网络性能的重要影响,在NS2(Network Simulator version 2)中加入了代表障碍物的概率穿透模型,使仿真环境更接近真实环境。针对AODV(Ad hoc On-Demand Distance Vector Routing)协议应用在城市场景下的缺陷,提出了一种改进的AODV协议——GE-AODV(Geocast Enhanced AODV)协议,该协议是基于位置信息的协议,并采用了多播方式来转发控制信息。仿真表明,GE-AODV降低了网络时延和控制开销,提高了网络可靠性。展开更多
文摘Using the fundamental adsorption equilibrium and kinetic parameters obtained from batch experiments, the mass transport and hydrodynamic behavior in the expanded bed of DEAE Spherodex M was analyzed with the breakthrough model. The results showed that the effect of particle size on breakthrough behavior was obviously greater than that of other parameters.The change of the time of 5% breakthrough, with increasing and decreasing mean particle diameter by a factor of 2, reached about 40% relative to that with the mean diameter, 88 μm. Secondary effects on expanded bed adsorption were film mass transfer and pore diffusion (<10%). Axial dispersion in solid phase had almost negligible effect on the adsorption process. Therefore, the assumption of even dispersion of adsorbent within the expanded bed may result in the model discrepancy to a great extent. It is considered that the breakthrough model can be further improved by taking into account particle size distribution in the expanded bed.
