The objective of this work is to develop a novel methodology for determining real resistivity of conductive asphalt concrete based on two-electrode method.Due to an influence of contact resistance,the measured resisti...The objective of this work is to develop a novel methodology for determining real resistivity of conductive asphalt concrete based on two-electrode method.Due to an influence of contact resistance,the measured resistivity is always not equal to the real resistivity.To determine the real resistivity,a linear relationship of the measured resistivity,contact resistance and the real resistivity was established.Then experiments for six specimens with varying graphite contents were designed and performed to validate the formulation.Results of experiments demonstrate that the slope of the line represents contact resistance,and the intercept indicates the real resistivity.The effects of graphite content on contact resistance and real resistivity are also revealed.Finally,results show that the influence of contact resistance on accuracy of resisitvity measurement becomes more serious if graphite content is beyond 3%.Hence,it is the time to choose this novel methodology to determine the real resistivity of asphalt concrete by taking account of contact resistance.展开更多
In the frame of the ZeuS-Ill project, a model study was started on evaluation the area-specific resistances （ASRs） of various layers being used in SOFC stacks. It is well known that stack performance not only depend...In the frame of the ZeuS-Ill project, a model study was started on evaluation the area-specific resistances （ASRs） of various layers being used in SOFC stacks. It is well known that stack performance not only depends on cell resistance but also on the electrical conductivity of the various applied contact and protective layers. Various layers have been tested under simulated SOFC conditions, and results have shown that the lowest ASR value, about 3 mΩ.cm2, was obtained for an LSM （2） contact layer. A significantly higher resistance was found for the combined contact and protective layer LCC10-Mn3O4, being around 37 mΩ.cm2 Related to the various tests, the total ASR of an F-design stack, developed by Forschungszentrum Jiilich, under ideal conditions can be estimated. In this case the ASR value was calculated as the sum of that of the LCC10-Mn3O4 layer and the formed oxide scale due to oxidation of Crofer22APU. Contacting resistance at the anode side was considered negligible. When differences in the ASR values occurred when compared with that from current-voltage measurements performed with real SOFC stacks, this can be explained by the limited contact area between interconnect and cathode. These results can be used to model the influence of various applied layers and different geometric contact areas on the overall ASR as determined from performance measurements with SOFC stacks.展开更多
Contact resistance at the interface between metal electrodes and semiconductors can significantly limit the performance of organic field-effect transistors, leading to a distinct voltage drop at the interface. Here, w...Contact resistance at the interface between metal electrodes and semiconductors can significantly limit the performance of organic field-effect transistors, leading to a distinct voltage drop at the interface. Here, we demonstrate enhanced performance of n-channel field-effect transistors based on solution-grown C60 single-crystalline ribbons by introducing an interlayer of a conjugated polyelectrolyte （CPE） composed of poly[（9,9-bis（3＇-（（N,N-dimethyl）-N-ethylammonium）-propyl）-2,7-fluorene）- alt-2,7-（9,9-dioctylfluorene）] dibromide （PFN＋Br-）. The PFN＋Br- interlayer greatly improves the charge injection. Consequently, the electron mobility is promoted up to 5.60 cm2 V-1 s-1 and the threshold voltage decreased dramatically with the minimum of 4.90 V.展开更多
基金Project(51178348)supported by the National Natural Science Foundation of China
文摘The objective of this work is to develop a novel methodology for determining real resistivity of conductive asphalt concrete based on two-electrode method.Due to an influence of contact resistance,the measured resistivity is always not equal to the real resistivity.To determine the real resistivity,a linear relationship of the measured resistivity,contact resistance and the real resistivity was established.Then experiments for six specimens with varying graphite contents were designed and performed to validate the formulation.Results of experiments demonstrate that the slope of the line represents contact resistance,and the intercept indicates the real resistivity.The effects of graphite content on contact resistance and real resistivity are also revealed.Finally,results show that the influence of contact resistance on accuracy of resisitvity measurement becomes more serious if graphite content is beyond 3%.Hence,it is the time to choose this novel methodology to determine the real resistivity of asphalt concrete by taking account of contact resistance.
文摘In the frame of the ZeuS-Ill project, a model study was started on evaluation the area-specific resistances （ASRs） of various layers being used in SOFC stacks. It is well known that stack performance not only depends on cell resistance but also on the electrical conductivity of the various applied contact and protective layers. Various layers have been tested under simulated SOFC conditions, and results have shown that the lowest ASR value, about 3 mΩ.cm2, was obtained for an LSM （2） contact layer. A significantly higher resistance was found for the combined contact and protective layer LCC10-Mn3O4, being around 37 mΩ.cm2 Related to the various tests, the total ASR of an F-design stack, developed by Forschungszentrum Jiilich, under ideal conditions can be estimated. In this case the ASR value was calculated as the sum of that of the LCC10-Mn3O4 layer and the formed oxide scale due to oxidation of Crofer22APU. Contacting resistance at the anode side was considered negligible. When differences in the ASR values occurred when compared with that from current-voltage measurements performed with real SOFC stacks, this can be explained by the limited contact area between interconnect and cathode. These results can be used to model the influence of various applied layers and different geometric contact areas on the overall ASR as determined from performance measurements with SOFC stacks.
基金supported by the National Basic Research Program of China(2014CB643503)the National Natural Science Foundation of China(51625304,51373150,51461165301)the Zhejiang Province Natural Science Foundation(LZ13E030002)
文摘Contact resistance at the interface between metal electrodes and semiconductors can significantly limit the performance of organic field-effect transistors, leading to a distinct voltage drop at the interface. Here, we demonstrate enhanced performance of n-channel field-effect transistors based on solution-grown C60 single-crystalline ribbons by introducing an interlayer of a conjugated polyelectrolyte （CPE） composed of poly[（9,9-bis（3＇-（（N,N-dimethyl）-N-ethylammonium）-propyl）-2,7-fluorene）- alt-2,7-（9,9-dioctylfluorene）] dibromide （PFN＋Br-）. The PFN＋Br- interlayer greatly improves the charge injection. Consequently, the electron mobility is promoted up to 5.60 cm2 V-1 s-1 and the threshold voltage decreased dramatically with the minimum of 4.90 V.
