The contact effect on the performances of organic thin film transistors is studied here. A C60 ultrathin layer is inserted between Al source-drain electrode and pentacene to reduce the contact resistance. By a 3 nm C6...The contact effect on the performances of organic thin film transistors is studied here. A C60 ultrathin layer is inserted between Al source-drain electrode and pentacene to reduce the contact resistance. By a 3 nm C60 modification, the injection barrier is lowered and the contact resistance is reduced. Thus, the field-effect mobility increases from 0.12 to 0.52 cm2/(V.s). It means that inserting a C60 ultra thin layer is a good method to improve the organic thin film transistor (OTFT) performance. The output curve is simulated by using a charge drift model. Considering the contact effect, the field effect mobility is improved to 1.15 cm2/(V-s). It indicates that further reducing the contact resistance of OTFTs should be carried out.展开更多
Based on the X-13-ARIMA-SEATS model, aiming at the problem of mobile holidays in China’s economic data, this paper introduces a new method of seasonal adjustment based on the AICC criterion to objectively select the ...Based on the X-13-ARIMA-SEATS model, aiming at the problem of mobile holidays in China’s economic data, this paper introduces a new method of seasonal adjustment based on the AICC criterion to objectively select the parameters of dummy variables of mobile holidays. Taking the current total value of China’s import and export as an example, we expound</span><span style="font-family:""> </span><span style="font-family:Verdana;">a new method for seasonal adjustment of mobile holidays such as Spring Festival, Dragon Boat Festival and Mid-Autumn Festival. Finally, the model is used to predict the total value of China’s import and export in and out of the sample. The prediction results show that the relative error of the out of sample data is less than 5%. The new method has advantages in the processing of macroeconomic data.展开更多
Indications exist that mobile phones may cause non-specific biological effects. They are classified as being of implausible non-thermal nature due to low quantum energy and low specific absorption rate levels, even if...Indications exist that mobile phones may cause non-specific biological effects. They are classified as being of implausible non-thermal nature due to low quantum energy and low specific absorption rate levels, even if considering worst cases of "hot spots" of only millimeter size. The considerations of this paper demonstrate that classical theory of polarization offers a conventional interpretation for all three the existence of so far unclarified effects, their low reproducibility and their low intensity. The basis of this explanation is given by the assumption that hot spots contain even hotter “nano spots” on a molecular level according to well known mechanisms of γ-relaxation. In this paper, the concept is put for discussion assuming a heterogeneous system that consists of water molecules as well as larger-sized functional molecules. A consistent interpretation through temperature increase on the level of nanometer sized molecular compounds promises to favor interdisciplinary discussions with respect to safety regulations.展开更多
Sepsis and subsequent multiple organ dysfunction syndrome(MODS) are frequent complications after severe traumata or burns involving a large area,and these remain as the two most common causes of morbidity and mortalit...Sepsis and subsequent multiple organ dysfunction syndrome(MODS) are frequent complications after severe traumata or burns involving a large area,and these remain as the two most common causes of morbidity and mortality in critical illnesses.Despite the recent rapid advances in intensive展开更多
Three-dimensional(3D)nanoscale crystal shaping has become essential for the precise design of advanced electronic and quantum devices based on electrically gated transport.In this context,Ⅲ-Ⅴ semiconductor-based nan...Three-dimensional(3D)nanoscale crystal shaping has become essential for the precise design of advanced electronic and quantum devices based on electrically gated transport.In this context,Ⅲ-Ⅴ semiconductor-based nanowires with low electron effective mass and strong spin-orbit coupling are particularly investigated because of their exceptional quantum transport properties and the good electrostatic control they provide.Among the main challenges involved in the processing of these nanodevices are(i)the management of the gate stack which requires ex-situ passivation treatment to reduce the density of traps at the oxide/semiconductor interface,(ii)the ability to get good ohmic contacts for source and drain electrodes and(iii)the scalability and reliability of the process for the fabrication of complex architectures based on nanowire networks.In this paper,we show that selective area molecular beam epitaxy of in-plane InGaAs/InP core-shell nanowires with raised heavily doped source and drain contacts can address these different issues.Electrical characterization of the devices down to 4 K reveals the positive impact of the InP shell on the gate electrostatic control and effective electron mobility.Although comparable to the best reported values for In(Ga)As nanostructures grown on InP,this latter is severely reduced for sub-100 nm channel highlighting remaining issue to reach the ballistic regime.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.10774013,10974013,60978060 and 10804006)the Research Fund for the Doctoral Program of Higher Education,China(Grant Nos.20090009110027,20070004024 and 20070004031)+1 种基金the Beijing Municipal Science and Technology Commission(Grant No.1102028)the National Basic Research Program of China(Grant No.2010CB327704)
文摘The contact effect on the performances of organic thin film transistors is studied here. A C60 ultrathin layer is inserted between Al source-drain electrode and pentacene to reduce the contact resistance. By a 3 nm C60 modification, the injection barrier is lowered and the contact resistance is reduced. Thus, the field-effect mobility increases from 0.12 to 0.52 cm2/(V.s). It means that inserting a C60 ultra thin layer is a good method to improve the organic thin film transistor (OTFT) performance. The output curve is simulated by using a charge drift model. Considering the contact effect, the field effect mobility is improved to 1.15 cm2/(V-s). It indicates that further reducing the contact resistance of OTFTs should be carried out.
文摘Based on the X-13-ARIMA-SEATS model, aiming at the problem of mobile holidays in China’s economic data, this paper introduces a new method of seasonal adjustment based on the AICC criterion to objectively select the parameters of dummy variables of mobile holidays. Taking the current total value of China’s import and export as an example, we expound</span><span style="font-family:""> </span><span style="font-family:Verdana;">a new method for seasonal adjustment of mobile holidays such as Spring Festival, Dragon Boat Festival and Mid-Autumn Festival. Finally, the model is used to predict the total value of China’s import and export in and out of the sample. The prediction results show that the relative error of the out of sample data is less than 5%. The new method has advantages in the processing of macroeconomic data.
文摘Indications exist that mobile phones may cause non-specific biological effects. They are classified as being of implausible non-thermal nature due to low quantum energy and low specific absorption rate levels, even if considering worst cases of "hot spots" of only millimeter size. The considerations of this paper demonstrate that classical theory of polarization offers a conventional interpretation for all three the existence of so far unclarified effects, their low reproducibility and their low intensity. The basis of this explanation is given by the assumption that hot spots contain even hotter “nano spots” on a molecular level according to well known mechanisms of γ-relaxation. In this paper, the concept is put for discussion assuming a heterogeneous system that consists of water molecules as well as larger-sized functional molecules. A consistent interpretation through temperature increase on the level of nanometer sized molecular compounds promises to favor interdisciplinary discussions with respect to safety regulations.
基金Supported,in part,by Grants from the National Basic Research Program of China(No.2005CB522602)National Natural Science Foundation of China(No.30672178,30872683,30800437)National Natural Science Outstanding Youth Foundation of China(No.30125020)
文摘Sepsis and subsequent multiple organ dysfunction syndrome(MODS) are frequent complications after severe traumata or burns involving a large area,and these remain as the two most common causes of morbidity and mortality in critical illnesses.Despite the recent rapid advances in intensive
文摘Three-dimensional(3D)nanoscale crystal shaping has become essential for the precise design of advanced electronic and quantum devices based on electrically gated transport.In this context,Ⅲ-Ⅴ semiconductor-based nanowires with low electron effective mass and strong spin-orbit coupling are particularly investigated because of their exceptional quantum transport properties and the good electrostatic control they provide.Among the main challenges involved in the processing of these nanodevices are(i)the management of the gate stack which requires ex-situ passivation treatment to reduce the density of traps at the oxide/semiconductor interface,(ii)the ability to get good ohmic contacts for source and drain electrodes and(iii)the scalability and reliability of the process for the fabrication of complex architectures based on nanowire networks.In this paper,we show that selective area molecular beam epitaxy of in-plane InGaAs/InP core-shell nanowires with raised heavily doped source and drain contacts can address these different issues.Electrical characterization of the devices down to 4 K reveals the positive impact of the InP shell on the gate electrostatic control and effective electron mobility.Although comparable to the best reported values for In(Ga)As nanostructures grown on InP,this latter is severely reduced for sub-100 nm channel highlighting remaining issue to reach the ballistic regime.