The filtered cathodic vacuum-arc (FCVA) technique is a supplementary and alterna tive technique with respect to convendtional physical and chemical vapour deposi tion which can remove macro-particles effectively and m...The filtered cathodic vacuum-arc (FCVA) technique is a supplementary and alterna tive technique with respect to convendtional physical and chemical vapour deposi tion which can remove macro-particles effectively and make the deposition proces s at ambient temperature. In this work, high quality TiN thin films were deposi ted on silicon substrates at low temperature using the improved filtered cathodi c arc plasma (FCAP) technique. AFM, XRD, TEM were employed to characterize the T iN thin films. The effects of the negative substrate bias on the grain size, pre ferred crystalline orientation, surface roughness of TiN thin films were discuss ed.展开更多
Here a new scheme for mode filtering is proposed. Based on the ponderomotive force effect,propagation of the microwave dual-mode through a plasma-filled metallic rectangular waveguide is investigated. To excite the TE...Here a new scheme for mode filtering is proposed. Based on the ponderomotive force effect,propagation of the microwave dual-mode through a plasma-filled metallic rectangular waveguide is investigated. To excite the TE_（20） mode in a rectangular waveguide, the existence of fundamental modes is unavoidable. To filter the destructive mode（TE_（10））, the waveguide is filled with a collisional plasma. Based on the coupling effect, the energy of this destructive TE_（10） mode is transferred to the TE_（20） mode. The proposed structure acts like a mode convertor. The TE_（10） mode become more attenuated and instead the TE_（20） mode is amplified. The plasma filled rectangular waveguide acts as a mode filtering tool.展开更多
The electron energy distribution function （EEDF） for a magnetically filtered dusty plasma is studied in a dusty double plasma device where the electron energy can be varied from 0.15 eV to ～ 2.8 eV and plasma densi...The electron energy distribution function （EEDF） for a magnetically filtered dusty plasma is studied in a dusty double plasma device where the electron energy can be varied from 0.15 eV to ～ 2.8 eV and plasma density from 10 6 cm-3 to 10 9cm-3 . The characteristics of EEDF for these ranges of plasma parameters are investigated in a pristine plasma as well as in a dusty plasma. The results show that in the presence of dust, there is a drastic modification in EEDF patterns in a plasma with higher electron temperature and density than those in a low temperature and low density plasma produced by the magnetic filter.展开更多
A tunable dual-narrowband pass-band filter is designed. A one-dimensional photonic crystal （1D PC） is comprised of alternate dielectric layer and vacuum layer. Two quantum wells （QWs） as defects can be constructed...A tunable dual-narrowband pass-band filter is designed. A one-dimensional photonic crystal （1D PC） is comprised of alternate dielectric layer and vacuum layer. Two quantum wells （QWs） as defects can be constructed by sandwiching two plasma slabs symmetrically in the 1D PC, and a dual-narrowband pass-band filter is formed. The conventional finite- difference time-domain （FDTD） method and piecewise linear current density recursive convolution （PLCDRC）-FDTD method are applied to the dielectric and plasma, respectively. The simulation results illustrate that the dual-narrowband frequencies can be tuned by changing the plasma frequency. The pass band interval and the half-power bandwidths （-3-dB band widths） are related to the space interval between two QWs.展开更多
A Kalman filter was developed for correction of wing interference in ICP-AES.Modeling wing interference theoretically instead of experimentally, the filter can compensate the shift in wavelength position in scans, and...A Kalman filter was developed for correction of wing interference in ICP-AES.Modeling wing interference theoretically instead of experimentally, the filter can compensate the shift in wavelength position in scans, and therefore reduce the effect of the interference on detection limit.展开更多
A novel photonic crystal fiber（PCF） polarization filter is designed and fabricated; it consists of two large apertures coated with gold. The asymmetric structure separates the resonance position in the vertical dire...A novel photonic crystal fiber（PCF） polarization filter is designed and fabricated; it consists of two large apertures coated with gold. The asymmetric structure separates the resonance position in the vertical direction well. Due to the metal layer covering, loss is greatly improved. Finite element method is applied for numerical simulation. The influences of varying gold thickness and varying the diameters and the center positions of the larger apertures on filtering performance are evaluated. Theory of coupling between surface plasma and core mode is introduced. By modulating the parameters, we realize a single polarization filter at 1.31 μm and 1.55 μm. The basal mode loss in the y direction can reach 1408.80 dB/cm at 1.31 μm and 1911.22 dB/cm at 1.55 μm respectively, but basal mode loss in the x direction is relatively small, 0.82 dB/cm and 1.87 dB/cm. In addition, two kinds of broadband polarization filters are proposed. If the fiber length is set to 200 μm,the extinction ratio is greater than 20 dB with width of 570 nm and 490 nm. The filter has simple structure and excellent performance.展开更多
The spatial structure of remote plasma regions in rf discharges is analyzed based on a 2D model of free-fall regime discharge maintenance. Since the study is directed towards description of the magnetic filter region ...The spatial structure of remote plasma regions in rf discharges is analyzed based on a 2D model of free-fall regime discharge maintenance. Since the study is directed towards description of the magnetic filter region in the tandem plasma sources of negative hydrogen ions, hydrogen discharges are considered, with a weak magnetic field located outside the region of the rf power deposition. With the formation of different regions in the discharge—the rf power deposition region, the region with electron magnetization, the transition between them and the region behind the filter—the results display superimposed effects of nonlocal discharge maintenance without and with a magnetic field. Slight decrease of the electron temperature accompanied with strong drop of the electron density is the “pure” effect of the plasma expansion in regions without external magnetic field. Strong drop of the electron temperature accompanied with formation of a maximum of the electron density in the filter region is the “pure” effect of the plasma expansion through a magnetic field. Based on the results for the spatial distribution of the electron density and temperature obtained with shifting the position of the magnetic filter, optimization of the source regarding high yield of volume-produced negative ions is discussed.展开更多
A coding and decoding process of argon plasma images using digital holography is proposed. The digital Fourier holography is applied to two images of matrix dimensions 512 × 512 pixels. The decoded images are imp...A coding and decoding process of argon plasma images using digital holography is proposed. The digital Fourier holography is applied to two images of matrix dimensions 512 × 512 pixels. The decoded images are improved using wiener filtering techniques. We have constructed three basic color images of the original image which is useful to extract the thermal distribution of the plasma image. Also, the profiles of the reconstructed images are checked showing better smooth profiles using wiener filter. The Mat-lab code is applied in the operation of image processing using Fourier techniques.展开更多
A major obstacle to the broad application of cathodic arc plasma deposition is the presence of macroparticles. In this paper, the properties of the large rectangular arc ion plating with a magnetic filtering shutter s...A major obstacle to the broad application of cathodic arc plasma deposition is the presence of macroparticles. In this paper, the properties of the large rectangular arc ion plating with a magnetic filtering shutter system to filter macroparticles are studied. It is proposed that the macroparticles in the plasma beam are effectively removed with the magnetic filtering shutter system, and the quality of the deposited films is improved.展开更多
A systematic approach to the design of the conducted electromagnetic interference （EMI） filter of high-density plasma cutting power supply has been developed. Converter components have been accurately modeled, with ...A systematic approach to the design of the conducted electromagnetic interference （EMI） filter of high-density plasma cutting power supply has been developed. Converter components have been accurately modeled, with parasitic elements extracted to reveal their impacts on the EMI noises. Circuit simulations have been used to analyze and minimize the EMI noises. Conducted EMI noise measurement and filter design of this power supply have been achieved which successfully satisfy the FCC class B limits in the frequency range from 150 kHz to 30 MHz. The analyses and experimental results show that the designed filter guarantees that the required attenuation will be achieved.展开更多
为解决废气再循环(Exhaust Gas Re-circulation,EGR)系统冷却器、电控阀等部件的积碳腐蚀问题,设计了一种放置于EGR系统前端的净化装置。该装置的连接层由管道法兰和紧固件组成;激化绝缘层由铁丝圈和绝缘环等组成;净化过滤层采用了低温...为解决废气再循环(Exhaust Gas Re-circulation,EGR)系统冷却器、电控阀等部件的积碳腐蚀问题,设计了一种放置于EGR系统前端的净化装置。该装置的连接层由管道法兰和紧固件组成;激化绝缘层由铁丝圈和绝缘环等组成;净化过滤层采用了低温等离子体发生器和陶瓷过滤体;电源系统采用了整流滤波稳压电路和逆变电路,能将220 V交流电转化为频率可调的脉冲电。由于设计了高频变压器,因此该装置的电源系统能将电压幅值增大至净化装置工作所需的值。展开更多
基金This work was supported by the National Natural Science Foundation of China(No.10074022)the Excellent Young Teachers Prograom of MOE,China.
文摘The filtered cathodic vacuum-arc (FCVA) technique is a supplementary and alterna tive technique with respect to convendtional physical and chemical vapour deposi tion which can remove macro-particles effectively and make the deposition proces s at ambient temperature. In this work, high quality TiN thin films were deposi ted on silicon substrates at low temperature using the improved filtered cathodi c arc plasma (FCAP) technique. AFM, XRD, TEM were employed to characterize the T iN thin films. The effects of the negative substrate bias on the grain size, pre ferred crystalline orientation, surface roughness of TiN thin films were discuss ed.
基金supported by Hormoz branch, Islamic Azad University, Iran, Hormoze Island grant
文摘Here a new scheme for mode filtering is proposed. Based on the ponderomotive force effect,propagation of the microwave dual-mode through a plasma-filled metallic rectangular waveguide is investigated. To excite the TE_（20） mode in a rectangular waveguide, the existence of fundamental modes is unavoidable. To filter the destructive mode（TE_（10））, the waveguide is filled with a collisional plasma. Based on the coupling effect, the energy of this destructive TE_（10） mode is transferred to the TE_（20） mode. The proposed structure acts like a mode convertor. The TE_（10） mode become more attenuated and instead the TE_（20） mode is amplified. The plasma filled rectangular waveguide acts as a mode filtering tool.
文摘The electron energy distribution function （EEDF） for a magnetically filtered dusty plasma is studied in a dusty double plasma device where the electron energy can be varied from 0.15 eV to ～ 2.8 eV and plasma density from 10 6 cm-3 to 10 9cm-3 . The characteristics of EEDF for these ranges of plasma parameters are investigated in a pristine plasma as well as in a dusty plasma. The results show that in the presence of dust, there is a drastic modification in EEDF patterns in a plasma with higher electron temperature and density than those in a low temperature and low density plasma produced by the magnetic filter.
基金supported by the Aviation Science Foundation(Key Project 20121852030)Jiangsu Provincial Natural Science Foundation,China(Grant No.BK2011727)the Open Research Program in Jiangsu Provincial Key Laboratory of Meteorological Observation and Information Processing,China(Grant No.KDXS1207)
文摘A tunable dual-narrowband pass-band filter is designed. A one-dimensional photonic crystal （1D PC） is comprised of alternate dielectric layer and vacuum layer. Two quantum wells （QWs） as defects can be constructed by sandwiching two plasma slabs symmetrically in the 1D PC, and a dual-narrowband pass-band filter is formed. The conventional finite- difference time-domain （FDTD） method and piecewise linear current density recursive convolution （PLCDRC）-FDTD method are applied to the dielectric and plasma, respectively. The simulation results illustrate that the dual-narrowband frequencies can be tuned by changing the plasma frequency. The pass band interval and the half-power bandwidths （-3-dB band widths） are related to the space interval between two QWs.
文摘A Kalman filter was developed for correction of wing interference in ICP-AES.Modeling wing interference theoretically instead of experimentally, the filter can compensate the shift in wavelength position in scans, and therefore reduce the effect of the interference on detection limit.
基金Project supported by the National Natural Science Foundation of China(Grants Nos.61475134 and 61505175)Key Program of the Natural Science Foundation of He Bei Province,China(Grant No.F2017203193)
文摘A novel photonic crystal fiber（PCF） polarization filter is designed and fabricated; it consists of two large apertures coated with gold. The asymmetric structure separates the resonance position in the vertical direction well. Due to the metal layer covering, loss is greatly improved. Finite element method is applied for numerical simulation. The influences of varying gold thickness and varying the diameters and the center positions of the larger apertures on filtering performance are evaluated. Theory of coupling between surface plasma and core mode is introduced. By modulating the parameters, we realize a single polarization filter at 1.31 μm and 1.55 μm. The basal mode loss in the y direction can reach 1408.80 dB/cm at 1.31 μm and 1911.22 dB/cm at 1.55 μm respectively, but basal mode loss in the x direction is relatively small, 0.82 dB/cm and 1.87 dB/cm. In addition, two kinds of broadband polarization filters are proposed. If the fiber length is set to 200 μm,the extinction ratio is greater than 20 dB with width of 570 nm and 490 nm. The filter has simple structure and excellent performance.
文摘The spatial structure of remote plasma regions in rf discharges is analyzed based on a 2D model of free-fall regime discharge maintenance. Since the study is directed towards description of the magnetic filter region in the tandem plasma sources of negative hydrogen ions, hydrogen discharges are considered, with a weak magnetic field located outside the region of the rf power deposition. With the formation of different regions in the discharge—the rf power deposition region, the region with electron magnetization, the transition between them and the region behind the filter—the results display superimposed effects of nonlocal discharge maintenance without and with a magnetic field. Slight decrease of the electron temperature accompanied with strong drop of the electron density is the “pure” effect of the plasma expansion in regions without external magnetic field. Strong drop of the electron temperature accompanied with formation of a maximum of the electron density in the filter region is the “pure” effect of the plasma expansion through a magnetic field. Based on the results for the spatial distribution of the electron density and temperature obtained with shifting the position of the magnetic filter, optimization of the source regarding high yield of volume-produced negative ions is discussed.
文摘A coding and decoding process of argon plasma images using digital holography is proposed. The digital Fourier holography is applied to two images of matrix dimensions 512 × 512 pixels. The decoded images are improved using wiener filtering techniques. We have constructed three basic color images of the original image which is useful to extract the thermal distribution of the plasma image. Also, the profiles of the reconstructed images are checked showing better smooth profiles using wiener filter. The Mat-lab code is applied in the operation of image processing using Fourier techniques.
文摘A major obstacle to the broad application of cathodic arc plasma deposition is the presence of macroparticles. In this paper, the properties of the large rectangular arc ion plating with a magnetic filtering shutter system to filter macroparticles are studied. It is proposed that the macroparticles in the plasma beam are effectively removed with the magnetic filtering shutter system, and the quality of the deposited films is improved.
基金National Natural Science Foundation of China (No. 50477009)
文摘A systematic approach to the design of the conducted electromagnetic interference （EMI） filter of high-density plasma cutting power supply has been developed. Converter components have been accurately modeled, with parasitic elements extracted to reveal their impacts on the EMI noises. Circuit simulations have been used to analyze and minimize the EMI noises. Conducted EMI noise measurement and filter design of this power supply have been achieved which successfully satisfy the FCC class B limits in the frequency range from 150 kHz to 30 MHz. The analyses and experimental results show that the designed filter guarantees that the required attenuation will be achieved.
文摘为解决废气再循环(Exhaust Gas Re-circulation,EGR)系统冷却器、电控阀等部件的积碳腐蚀问题,设计了一种放置于EGR系统前端的净化装置。该装置的连接层由管道法兰和紧固件组成;激化绝缘层由铁丝圈和绝缘环等组成;净化过滤层采用了低温等离子体发生器和陶瓷过滤体;电源系统采用了整流滤波稳压电路和逆变电路,能将220 V交流电转化为频率可调的脉冲电。由于设计了高频变压器,因此该装置的电源系统能将电压幅值增大至净化装置工作所需的值。
