Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement m...Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement mechanism of RMFs on semiconductor bridge(SCB)during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics devices.In this study,a one-dimensional(1D)gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO_(3) RMFs.In order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process,the heat release of chemical reaction in RMFs was used as an internal heat source in this model.It is found that the exothermal reaction in RMFs improved the ignition performance of SCB.In the process of plasma rapid condensation with heat release,the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle,which accelerated the expansion of hot plasma,and heated the solid charge particle as well as gas phase region with low temperature.In addition,it made up for pressure loss in the gas phase.During the plasma dissipation process,the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle,making the surface temperature of the charge particle,gas pressure,and gas temperature rise continuously.This result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices.展开更多
Multilayer gallium and aluminum doped ZnO (GZO/AZO) films were fabricated by alternative deposition of Ga-doped zinc oxide(GZO) and Al-doped zinc oxide(AZO) thin film by using pulsed laser deposition(PLD) process. The...Multilayer gallium and aluminum doped ZnO (GZO/AZO) films were fabricated by alternative deposition of Ga-doped zinc oxide(GZO) and Al-doped zinc oxide(AZO) thin film by using pulsed laser deposition(PLD) process. The electrical and optical properties of these GZO/AZO thin films were investigated and compared with those of GZO and AZO thin films. The GZO/AZO (1:1) thin film deposited at 400 °C shows the electrical resistivity of 4.18×10-4 Ω·cm, an electron concentration of 7.5×1020 /cm3, and carrier mobility of 25.4 cm2/(V·s). The optical transmittances of GZO/AZO thin films are over 85%. The optical band gap energy of GZO/AZO thin films linearly decreases with increasing the Al ratio.展开更多
Cu-Al/Al nanostructured metallic multilayers with Al layer thickness hAl varying from 5 to 100 nm were prepared, and their mechanical properties and deformation behaviors were studied by nanoindentation testing. The r...Cu-Al/Al nanostructured metallic multilayers with Al layer thickness hAl varying from 5 to 100 nm were prepared, and their mechanical properties and deformation behaviors were studied by nanoindentation testing. The results showed that the hardness increased drastically with decreasing hAl down to about 20 nm, whereafter the hardness reached a plateau that approaches the hardness of the alloyed Cu-Al monolithic thin films. The strain rate sensitivity （SRS, m）, however, decreased monotonically with reducing hAl. The layer thickness-dependent strengthening mechanisms were discussed, and it was revealed that the alloyed Cu-Al nanolayers dominated at hAl≤ 20 nm, while the crystalline Al nanolayers dominated at hAl 〉 20 nm. The plastic deformation was mainly related to the ductile Al nanolayers, which was responsible for the monotonic evolution of SRS with hAl. In addition, the hAFdependent hardness and SRS were quanti- tatively modeled in light of the strengthening mechanisms at different length scales.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.22275092,52102107 and 52372084)the Fundamental Research Funds for the Central Universities(Grant No.30923010920)。
文摘Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement mechanism of RMFs on semiconductor bridge(SCB)during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics devices.In this study,a one-dimensional(1D)gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO_(3) RMFs.In order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process,the heat release of chemical reaction in RMFs was used as an internal heat source in this model.It is found that the exothermal reaction in RMFs improved the ignition performance of SCB.In the process of plasma rapid condensation with heat release,the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle,which accelerated the expansion of hot plasma,and heated the solid charge particle as well as gas phase region with low temperature.In addition,it made up for pressure loss in the gas phase.During the plasma dissipation process,the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle,making the surface temperature of the charge particle,gas pressure,and gas temperature rise continuously.This result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices.
基金supported by the Yeungnam University Research Grants in 2009
文摘Multilayer gallium and aluminum doped ZnO (GZO/AZO) films were fabricated by alternative deposition of Ga-doped zinc oxide(GZO) and Al-doped zinc oxide(AZO) thin film by using pulsed laser deposition(PLD) process. The electrical and optical properties of these GZO/AZO thin films were investigated and compared with those of GZO and AZO thin films. The GZO/AZO (1:1) thin film deposited at 400 °C shows the electrical resistivity of 4.18×10-4 Ω·cm, an electron concentration of 7.5×1020 /cm3, and carrier mobility of 25.4 cm2/(V·s). The optical transmittances of GZO/AZO thin films are over 85%. The optical band gap energy of GZO/AZO thin films linearly decreases with increasing the Al ratio.
基金supported by the National Natural Science Foundation of China(Grant Nos.5132100351322104and 51201123)+5 种基金the National Basic Research Program of China(Grant No.2010CB631003)the 111 Project of China(Grant No.B06025)the support from the Fundamental Research Funds for the Central Universitiesthe Tengfei Scholar projectthe Natural Science Basic Research Plan in Shaanxi Province of China(Program No.2015JM5158)the Shaanxi Province Postdoctoral Scientific Research Project for partial financial support
文摘Cu-Al/Al nanostructured metallic multilayers with Al layer thickness hAl varying from 5 to 100 nm were prepared, and their mechanical properties and deformation behaviors were studied by nanoindentation testing. The results showed that the hardness increased drastically with decreasing hAl down to about 20 nm, whereafter the hardness reached a plateau that approaches the hardness of the alloyed Cu-Al monolithic thin films. The strain rate sensitivity （SRS, m）, however, decreased monotonically with reducing hAl. The layer thickness-dependent strengthening mechanisms were discussed, and it was revealed that the alloyed Cu-Al nanolayers dominated at hAl≤ 20 nm, while the crystalline Al nanolayers dominated at hAl 〉 20 nm. The plastic deformation was mainly related to the ductile Al nanolayers, which was responsible for the monotonic evolution of SRS with hAl. In addition, the hAFdependent hardness and SRS were quanti- tatively modeled in light of the strengthening mechanisms at different length scales.
