We put forth a project, that is: using the backscatter technique to realize adaptive long-distance HF broadcasting system in order to improve the quality of HF broadcasting. Then, we analyze errors of the system due t...We put forth a project, that is: using the backscatter technique to realize adaptive long-distance HF broadcasting system in order to improve the quality of HF broadcasting. Then, we analyze errors of the system due to the deviation of the ionospheric parameters' prediction. From the analysis, we draw the conclusion that our project is feasible. In addition, we point out that we can use frequency-spreading and information-coding technique to acquire more clear ionograms. We also offer a judgment on how to choose the control propagation mode on condition of multihop and the existence of more than one propagation mode on the signals' path.展开更多
The relation between the Mg treatment and ferrite grain boundaries misorientation was investigated. The orientation imaging microscopy technique based on electron backscattered diffraction technique （EBSD） was used ...The relation between the Mg treatment and ferrite grain boundaries misorientation was investigated. The orientation imaging microscopy technique based on electron backscattered diffraction technique （EBSD） was used in this work. （t was found that the addition of 0.005 wt% Mg to the steel could evidently increase the ratio of acicular ferrite crystals appearing at large angles boundaries to each other, which was attributed to the nucleation of the second-phase particles by the Mg treatment. The FBSD techniques provide a power- ful method to characterize and quantify the ferrite grain boundaries misorientation, in order to relate it to toughness.展开更多
Polarization fluctuation induced noise and backscattering-induced noise are the dominant noises in resonant fiber optic gyroscopes. This Letter proposes a new method to suppress the carrier and backscattering induced ...Polarization fluctuation induced noise and backscattering-induced noise are the dominant noises in resonant fiber optic gyroscopes. This Letter proposes a new method to suppress the carrier and backscattering induced noise by the sideband locking technique. Besides choosing an optimized modulation depth and different clockwise and counterclockwise modulation frequencies, the sideband is locked to the cavity resonance. With the proper modulation frequency, the carrier frequency component locates at a position far away from the resonant frequency, and then it is suppressed by the cavity itself, which can be taken as a bandpass filter. The amplitude of the carrier frequency can be suppressed by 20–25 d B additionally by the cavity and the total intensity suppression ratio can reach 115.74 d B. The backscattering induced noise can be eliminated for the adoption of different frequencies. The method can realize a stable and high suppression ratio without high requirements for parameter accuracy or device performance.展开更多
In situ observation of electron backscattering diffraction technique was used to evaluate the orientation relationships between austenite and α′-martensite（α′-M） for high manganese transformation-induced plastic...In situ observation of electron backscattering diffraction technique was used to evaluate the orientation relationships between austenite and α′-martensite（α′-M） for high manganese transformation-induced plasticity steel.It was noted that different from the thermal martensite,which well obeyed K-S relationship with austenite,the orientation relationship between deformation-induced α′-M with austenite changed during deformation,namely K-S and N-W relations coexisted.No clear differences existed between α′-M variants with two kinds of relationships in terms of martensitic orientation,shape and the misorientation between α′-M variants.And this phenomenon happened in almost all austenitic grains with different orientations investigated in this study.An atom displacement mechanism through conjugate complex slips of partial dislocations in the distorted fcc lattice was applied in this article to interpret the coexistence of K-S and N-W relationships.展开更多
Due to the need to reduce electronic device sizes, it is very important to consider the depth and lateral distribution of ions implanted into a crystalline target. This paper reports that Nd ions with energies of 200 ...Due to the need to reduce electronic device sizes, it is very important to consider the depth and lateral distribution of ions implanted into a crystalline target. This paper reports that Nd ions with energies of 200 keV to 500 keV and dose of 5× 10^15 ions/cm2 are implanted into Si single crystals at room temperature under the angles of 0°, 30°, and 45°, respectively. The lateral spreads of 200 keV-500 keV Nd ions implanted in Si sample are measured by Rutherford backscattering technique. The results show that the measured values are in good agreement with those obtained from the prediction of SRIM2010 codes.展开更多
The erbium ions at energy of 400 keV and dose of 5× 10^15 ions/cm^2 were implanted into silicon single crystals at room temperature at the angles of 0°,45° and 60°. The lateral spread of 400 keV er...The erbium ions at energy of 400 keV and dose of 5× 10^15 ions/cm^2 were implanted into silicon single crystals at room temperature at the angles of 0°,45° and 60°. The lateral spread of 400 keV erbium ions implanted in silicon sample was measured by the Rutherford backscattering technique. The results show that the measured values were in good agreement with those obtained from the prediction of TRIM＇98 （Transport of Ions in Matter） and SRIM2006 （Stopping and Range of Ions in Matter） codes.展开更多
文摘We put forth a project, that is: using the backscatter technique to realize adaptive long-distance HF broadcasting system in order to improve the quality of HF broadcasting. Then, we analyze errors of the system due to the deviation of the ionospheric parameters' prediction. From the analysis, we draw the conclusion that our project is feasible. In addition, we point out that we can use frequency-spreading and information-coding technique to acquire more clear ionograms. We also offer a judgment on how to choose the control propagation mode on condition of multihop and the existence of more than one propagation mode on the signals' path.
文摘The relation between the Mg treatment and ferrite grain boundaries misorientation was investigated. The orientation imaging microscopy technique based on electron backscattered diffraction technique （EBSD） was used in this work. （t was found that the addition of 0.005 wt% Mg to the steel could evidently increase the ratio of acicular ferrite crystals appearing at large angles boundaries to each other, which was attributed to the nucleation of the second-phase particles by the Mg treatment. The FBSD techniques provide a power- ful method to characterize and quantify the ferrite grain boundaries misorientation, in order to relate it to toughness.
文摘Polarization fluctuation induced noise and backscattering-induced noise are the dominant noises in resonant fiber optic gyroscopes. This Letter proposes a new method to suppress the carrier and backscattering induced noise by the sideband locking technique. Besides choosing an optimized modulation depth and different clockwise and counterclockwise modulation frequencies, the sideband is locked to the cavity resonance. With the proper modulation frequency, the carrier frequency component locates at a position far away from the resonant frequency, and then it is suppressed by the cavity itself, which can be taken as a bandpass filter. The amplitude of the carrier frequency can be suppressed by 20–25 d B additionally by the cavity and the total intensity suppression ratio can reach 115.74 d B. The backscattering induced noise can be eliminated for the adoption of different frequencies. The method can realize a stable and high suppression ratio without high requirements for parameter accuracy or device performance.
基金financially supported by the National Natural Science Foundation of China(No.51271028)
文摘In situ observation of electron backscattering diffraction technique was used to evaluate the orientation relationships between austenite and α′-martensite（α′-M） for high manganese transformation-induced plasticity steel.It was noted that different from the thermal martensite,which well obeyed K-S relationship with austenite,the orientation relationship between deformation-induced α′-M with austenite changed during deformation,namely K-S and N-W relations coexisted.No clear differences existed between α′-M variants with two kinds of relationships in terms of martensitic orientation,shape and the misorientation between α′-M variants.And this phenomenon happened in almost all austenitic grains with different orientations investigated in this study.An atom displacement mechanism through conjugate complex slips of partial dislocations in the distorted fcc lattice was applied in this article to interpret the coexistence of K-S and N-W relationships.
基金Project supported by the Shandong Jianzhu University Foundation,China(Grant No. XN070109)the National Natural Science Foundation of China (Grant No.51042002)
文摘Due to the need to reduce electronic device sizes, it is very important to consider the depth and lateral distribution of ions implanted into a crystalline target. This paper reports that Nd ions with energies of 200 keV to 500 keV and dose of 5× 10^15 ions/cm2 are implanted into Si single crystals at room temperature under the angles of 0°, 30°, and 45°, respectively. The lateral spreads of 200 keV-500 keV Nd ions implanted in Si sample are measured by Rutherford backscattering technique. The results show that the measured values are in good agreement with those obtained from the prediction of SRIM2010 codes.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10975094 and 10735070)the National Basic Research Program of China (Grant No. 2010CB832906)+1 种基金Program for New Century Excellent Talents in University,Ministry of Education of China (Grant No. NCET-07-0516)the Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No. 10422-2007B1)
文摘The erbium ions at energy of 400 keV and dose of 5× 10^15 ions/cm^2 were implanted into silicon single crystals at room temperature at the angles of 0°,45° and 60°. The lateral spread of 400 keV erbium ions implanted in silicon sample was measured by the Rutherford backscattering technique. The results show that the measured values were in good agreement with those obtained from the prediction of TRIM＇98 （Transport of Ions in Matter） and SRIM2006 （Stopping and Range of Ions in Matter） codes.
