A VME-based experiment system for n-y discrimination using the charge comparison method was established.A data acquisition program for controlling the programmable modules and processing data online via VME64X bus was...A VME-based experiment system for n-y discrimination using the charge comparison method was established.A data acquisition program for controlling the programmable modules and processing data online via VME64X bus was developed through the use of Lab VIEW.The two-dimensional（2D） scatter plots of the charge in the slow component vs.the total charge from ^（241）Am-Be and 252Cf neutron sources are presented.The 2D scatter plots of the energy vs.the ratio of the charge in the slow component to the total charge of the pulses are also presented.The quality of n-γ discrimination was checked by the figure-of-merit,and the results showed good performance of n-γ discrimination at the low energy range.Neutrons and γ-rays were separated above 50 keVee（electron-equivalent energy）.The quality of n-γ discrimination has been improved compared with others＇ results at five energies（150,250,350,450,550 keVee）.展开更多
Determination of the energy range is an important precondition of focus calibration using alignment procedure （FOCAL） test. A new method to determine the energy range of FOCAL off-lined is presented in this paper. I...Determination of the energy range is an important precondition of focus calibration using alignment procedure （FOCAL） test. A new method to determine the energy range of FOCAL off-lined is presented in this paper. Independent of the lithographic tool, the method is time-saving and effective. The influences of some process factors, e.g. resist thickness, post exposure bake （PEB） temperature, PEB time and development time, on the energy range of FOCAL are analyzed.展开更多
The resonance behaviors of local surface plasmon resonance in Au monomer and dimer are characterized sys- temically by electron energy loss spectroscopy in a scanning transmission electron microscope. The measured abs...The resonance behaviors of local surface plasmon resonance in Au monomer and dimer are characterized sys- temically by electron energy loss spectroscopy in a scanning transmission electron microscope. The measured absorption range is about 20nm larger than the physical size of the Au nanoparticles and the resonance peak energy shows a red shift when the electron beam passes off the nanoparticles. The Au dimer displays similar behaviors. Numerical simulation also reproduces those experimental results.展开更多
Objective A three-dimensional position-sensitive fast neutron spectrometer is designed to measure fast neutron spectrum over 10 MeV.Methods The detector consists of a 16×16 mutually perpendicular plastic scintill...Objective A three-dimensional position-sensitive fast neutron spectrometer is designed to measure fast neutron spectrum over 10 MeV.Methods The detector consists of a 16×16 mutually perpendicular plastic scintillation fiber array coupled to 2×2 Hamamatsu H8500C position-sensitive photomultiplier tubes by optical fibers.The fiber array is fabricated with 0.5 mm×3 mm fibers and 3-mm square fibers.Results Due to the combined application of different sizes of fibers,the detector can broaden energy dynamic range and meanwhile have good detection efficiency.The method of the combined application of different sizes of plastic fibers in the array may provide a solution to measure wider energy range of solar neutrons.Conclusion In this paper,we used FLUKA to simulate the performance of the detector model and report the results of experimental studies with neutrons from a pulsed D-T neutron.展开更多
文摘A VME-based experiment system for n-y discrimination using the charge comparison method was established.A data acquisition program for controlling the programmable modules and processing data online via VME64X bus was developed through the use of Lab VIEW.The two-dimensional（2D） scatter plots of the charge in the slow component vs.the total charge from ^（241）Am-Be and 252Cf neutron sources are presented.The 2D scatter plots of the energy vs.the ratio of the charge in the slow component to the total charge of the pulses are also presented.The quality of n-γ discrimination was checked by the figure-of-merit,and the results showed good performance of n-γ discrimination at the low energy range.Neutrons and γ-rays were separated above 50 keVee（electron-equivalent energy）.The quality of n-γ discrimination has been improved compared with others＇ results at five energies（150,250,350,450,550 keVee）.
文摘Determination of the energy range is an important precondition of focus calibration using alignment procedure （FOCAL） test. A new method to determine the energy range of FOCAL off-lined is presented in this paper. Independent of the lithographic tool, the method is time-saving and effective. The influences of some process factors, e.g. resist thickness, post exposure bake （PEB） temperature, PEB time and development time, on the energy range of FOCAL are analyzed.
基金Supported by the National Basic Research Program of China under Grant Nos 2013CB932904 and 2012CB932302the National Natural Science Foundation of China under Grant No 11274365
文摘The resonance behaviors of local surface plasmon resonance in Au monomer and dimer are characterized sys- temically by electron energy loss spectroscopy in a scanning transmission electron microscope. The measured absorption range is about 20nm larger than the physical size of the Au nanoparticles and the resonance peak energy shows a red shift when the electron beam passes off the nanoparticles. The Au dimer displays similar behaviors. Numerical simulation also reproduces those experimental results.
文摘Objective A three-dimensional position-sensitive fast neutron spectrometer is designed to measure fast neutron spectrum over 10 MeV.Methods The detector consists of a 16×16 mutually perpendicular plastic scintillation fiber array coupled to 2×2 Hamamatsu H8500C position-sensitive photomultiplier tubes by optical fibers.The fiber array is fabricated with 0.5 mm×3 mm fibers and 3-mm square fibers.Results Due to the combined application of different sizes of fibers,the detector can broaden energy dynamic range and meanwhile have good detection efficiency.The method of the combined application of different sizes of plastic fibers in the array may provide a solution to measure wider energy range of solar neutrons.Conclusion In this paper,we used FLUKA to simulate the performance of the detector model and report the results of experimental studies with neutrons from a pulsed D-T neutron.
