The overall objective of this study was to provide guidance for proper design of profile-walled pipe. Data from buried pipe tests on HDPE pipes with thirteen different profiles were included in the study. These tests ...The overall objective of this study was to provide guidance for proper design of profile-walled pipe. Data from buried pipe tests on HDPE pipes with thirteen different profiles were included in the study. These tests were run in the soil cell at Utah State University. Also, parallel plate tests were also completed on the pipe samples. Data from 39 buried pipe tests were analyzed. The buried tests were at 75, 85 and 95 percent of standard Proctor density. This paper summarizes the results of that study and focuses on the tests buried in 85 percent dense soil. In addition to the experimental data, a portion of this paper focuses on finite element analysis results to confirm and extend the results from the physical tests. Design limits are recommended for several dimensionless parameters that describe profile geometry. One of the significant conclusions of this study was that pipes with profiles that perform well when buried in soil also perform well in a parallel plate tests. The identities of the pipe manufacturers are not disclosed, and pipes are only described in terms of basic parameters such as cross-sectional area and area moments of inertia.展开更多
Organic phototransistors (OPTs) have been intensively studied in recent years due to the combined ad- vantages of phototransistors and organic semiconductors (OSCs). However, the electrical performance of OPTs is ...Organic phototransistors (OPTs) have been intensively studied in recent years due to the combined ad- vantages of phototransistors and organic semiconductors (OSCs). However, the electrical performance of OPTs is lar- gely limited by OSCs themselves, posing a challenge to further improve the performance of the devices. Preparing nano/mi- cro-structures of OSCs is considered as an effective way to improve the performance of OPTs. Polystyrene (PS) micro- sphere, as a kind of insulating and low-cost material, is ex- tensively used in fabricating nano/microporous structures, and the resulting devices exhibit high response to external stimuli. Therefore, we combined PS microspheres with OSCs to fabricate PS/OSC OPTs, and the Ilight/Idark ratio was en- hanced by two orders of magnitude compared with the pris- tine counterparts, which can be modulated from 46 to 1800 by controlling the diameters of PS microsphereso This strategy paves a way for developing high-performance OPTs with nano/microporous structures with potential applications in organic optoelectronics.展开更多
文摘The overall objective of this study was to provide guidance for proper design of profile-walled pipe. Data from buried pipe tests on HDPE pipes with thirteen different profiles were included in the study. These tests were run in the soil cell at Utah State University. Also, parallel plate tests were also completed on the pipe samples. Data from 39 buried pipe tests were analyzed. The buried tests were at 75, 85 and 95 percent of standard Proctor density. This paper summarizes the results of that study and focuses on the tests buried in 85 percent dense soil. In addition to the experimental data, a portion of this paper focuses on finite element analysis results to confirm and extend the results from the physical tests. Design limits are recommended for several dimensionless parameters that describe profile geometry. One of the significant conclusions of this study was that pipes with profiles that perform well when buried in soil also perform well in a parallel plate tests. The identities of the pipe manufacturers are not disclosed, and pipes are only described in terms of basic parameters such as cross-sectional area and area moments of inertia.
基金supported by the National Natural Science Foundation of China (51741302, 51603151 and 51373123)the National Key Research and Development Program of China (2017YFA0103900 and 2017YFA0103904)+1 种基金Science and Technology Foundation of Shanghai (17JC1404600)the Fundamental Research Funds for the Central Universities
文摘Organic phototransistors (OPTs) have been intensively studied in recent years due to the combined ad- vantages of phototransistors and organic semiconductors (OSCs). However, the electrical performance of OPTs is lar- gely limited by OSCs themselves, posing a challenge to further improve the performance of the devices. Preparing nano/mi- cro-structures of OSCs is considered as an effective way to improve the performance of OPTs. Polystyrene (PS) micro- sphere, as a kind of insulating and low-cost material, is ex- tensively used in fabricating nano/microporous structures, and the resulting devices exhibit high response to external stimuli. Therefore, we combined PS microspheres with OSCs to fabricate PS/OSC OPTs, and the Ilight/Idark ratio was en- hanced by two orders of magnitude compared with the pris- tine counterparts, which can be modulated from 46 to 1800 by controlling the diameters of PS microsphereso This strategy paves a way for developing high-performance OPTs with nano/microporous structures with potential applications in organic optoelectronics.