To verify the performance of the neutron total cross-sectional spectrometer, the neutron total cross section of carbon is initially measured in the energy range of 1 eV to 20 MeV using the time-of-flight method. The m...To verify the performance of the neutron total cross-sectional spectrometer, the neutron total cross section of carbon is initially measured in the energy range of 1 eV to 20 MeV using the time-of-flight method. The measurement is performed at the Back-n white neutron source with a 76-m time-of-flight path using the China Spallation Neutron Source. A multilayer fast fission chamber with 235U and 238U is employed as the neutron detector. The diameter and thickness of the natural graphite sample are 70 mm and 40 mm, respectively. Signal waveforms are collected using a data acquisition system. Off-line data processing was used to obtain the neutron time-of-flight spectra and transmissions. The uncertainty of the counting statistics is generally approximately 3% for each bin in the energy range of 1–20 MeV. It is determined that the results for the neutron total cross section of carbon obtained using ^235U cells are in good agreement with the results obtained using 238U cells within limits of statistical uncertainty. Moreover, the measured total cross sections show good agreement with the broadening evaluated data.展开更多
Poly（ionic liquid） functionalized composite nanotubes are achieved by ATRP grafting ionic liquid monomers for example ViEtIm^＋Br^- from the poly（DVB-co-VBC） nanotubes surface. PW12O40^3- anion is introduced throu...Poly（ionic liquid） functionalized composite nanotubes are achieved by ATRP grafting ionic liquid monomers for example ViEtIm^＋Br^- from the poly（DVB-co-VBC） nanotubes surface. PW12O40^3- anion is introduced through anion exchange. The PW12O40^3- based composite nanotubes can synchronously absorb and decompose water soluble dyes for example methyl orange（MO）. The cooperative interplay is promising in highly efficient decomposition of dyes.展开更多
基金supported by the National Key Research and Development Plan(No.2016YFA0401603)the National Natural Science Foundation of China(No.11675155)
文摘To verify the performance of the neutron total cross-sectional spectrometer, the neutron total cross section of carbon is initially measured in the energy range of 1 eV to 20 MeV using the time-of-flight method. The measurement is performed at the Back-n white neutron source with a 76-m time-of-flight path using the China Spallation Neutron Source. A multilayer fast fission chamber with 235U and 238U is employed as the neutron detector. The diameter and thickness of the natural graphite sample are 70 mm and 40 mm, respectively. Signal waveforms are collected using a data acquisition system. Off-line data processing was used to obtain the neutron time-of-flight spectra and transmissions. The uncertainty of the counting statistics is generally approximately 3% for each bin in the energy range of 1–20 MeV. It is determined that the results for the neutron total cross section of carbon obtained using ^235U cells are in good agreement with the results obtained using 238U cells within limits of statistical uncertainty. Moreover, the measured total cross sections show good agreement with the broadening evaluated data.
基金supported by MOST(No.2012CB933200)NSFC(Nos.51233007 and 51173191)
文摘Poly（ionic liquid） functionalized composite nanotubes are achieved by ATRP grafting ionic liquid monomers for example ViEtIm^＋Br^- from the poly（DVB-co-VBC） nanotubes surface. PW12O40^3- anion is introduced through anion exchange. The PW12O40^3- based composite nanotubes can synchronously absorb and decompose water soluble dyes for example methyl orange（MO）. The cooperative interplay is promising in highly efficient decomposition of dyes.
