High-temperature thermoelectric transport property measurements have been performed on the highly c-axis oriented Bi2Sr2Co20v thin films prepared by pulsed laser deposition on LaA1Oa (001). Both the electric resisti...High-temperature thermoelectric transport property measurements have been performed on the highly c-axis oriented Bi2Sr2Co20v thin films prepared by pulsed laser deposition on LaA1Oa (001). Both the electric resistivity p and the seebeck coefficient S of the film exhibit an increasing trend with the temperature from 300 K-1000 K and reach up to 4.8 m. cm and 202 V/K at 980 K, resulting in a power factor of 0.85 mW/mK which are comparable to those of the single crystalline samples. A small polaron hopping conduction can be responsible for the conduction mechanism of the film at high temperature. The results demonstrate that the Bi2Sr2Co2Oy thin film has potential application has high temperature thin film thermoelectric devices,展开更多
Experiments carried out using a lung model with a single horizontal bifurcation under different steady inhalation conditions explored the orientation of depositing carbon fibers, and particle deposition frac- tions. T...Experiments carried out using a lung model with a single horizontal bifurcation under different steady inhalation conditions explored the orientation of depositing carbon fibers, and particle deposition frac- tions. The orientations of deposited fibers were obtained from micrographs. Specifically, the effects of the sedimentation parameter (γ), fiber length, and flow rate on orientations were analyzed. Our results indicate that gravitational effect on deposition cannot be neglected for 0.0228 〈 γ 〈 0.247. The absolute orientation angle of depositing fibers decreased linearly with increasing y for values 0.0228 〈 γ 〈 0.15. Correspondence between Stokes numbers and y suggests these characteristics can be used to estimate fiber deposition in the lower airways. Computer simulations with sphere-equivalent diameter models for the fibers explored deposition efficiency vs. Stokes number. Using the volume-equivalent diameter model, our experimental data for the horizontal bifurcation were replicated. Results for particle deposition using a lung model with a vertical bifurcation indicate that body position also affects deposition.展开更多
基金Project supported by the Young Scientists Fund of the National Natural Science Foundation of China (Grant No. 10904030)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20091301120002)
文摘High-temperature thermoelectric transport property measurements have been performed on the highly c-axis oriented Bi2Sr2Co20v thin films prepared by pulsed laser deposition on LaA1Oa (001). Both the electric resistivity p and the seebeck coefficient S of the film exhibit an increasing trend with the temperature from 300 K-1000 K and reach up to 4.8 m. cm and 202 V/K at 980 K, resulting in a power factor of 0.85 mW/mK which are comparable to those of the single crystalline samples. A small polaron hopping conduction can be responsible for the conduction mechanism of the film at high temperature. The results demonstrate that the Bi2Sr2Co2Oy thin film has potential application has high temperature thin film thermoelectric devices,
基金We acknowledge the financial support of the Foundation for the National Natural Science Foundation of China (No. 51176035), and Author of National Excellent Doctoral Dissertation of China (No. 201040). In addition, financial support was provided to Xiaole Chen under the Research and Innovation Project for College Gradua- tes of Jiangsu Province (CXZZ12_0099), the Fundamental Research Funds for the Central Universities, China Scholarship Council (No. 201306090085), and Scientific Research Foundation of Graduate School of Southeast University (No. YBJJ1209). The experience gained by Xiaole Chen as a CSC-supported Visiting Student in the Computational Multi-Physics Lab (MAE Dept., NC State University, Raleigh, USA) is also acknowledged. Table 3, Figs. 5 and 7 were provided by Josin Tom, based on his spring 2015 course-project report for MAE558. Professor Goodarz Ahmadi at Clarkson Univer- sity (Clarkson, USA) provided advice for our experimental set-up, and Professor Yong Lu at Southeast University provided guidance in programming the image-processing method.
文摘Experiments carried out using a lung model with a single horizontal bifurcation under different steady inhalation conditions explored the orientation of depositing carbon fibers, and particle deposition frac- tions. The orientations of deposited fibers were obtained from micrographs. Specifically, the effects of the sedimentation parameter (γ), fiber length, and flow rate on orientations were analyzed. Our results indicate that gravitational effect on deposition cannot be neglected for 0.0228 〈 γ 〈 0.247. The absolute orientation angle of depositing fibers decreased linearly with increasing y for values 0.0228 〈 γ 〈 0.15. Correspondence between Stokes numbers and y suggests these characteristics can be used to estimate fiber deposition in the lower airways. Computer simulations with sphere-equivalent diameter models for the fibers explored deposition efficiency vs. Stokes number. Using the volume-equivalent diameter model, our experimental data for the horizontal bifurcation were replicated. Results for particle deposition using a lung model with a vertical bifurcation indicate that body position also affects deposition.