Study of e+e−→ppˉe^+e^- \rightarrow p\bar{p} in the vicinity of ψ(3770)\psi(3770)

Using 2917 $\rm{pb}^{-1}$ of data accumulated at 3.773~$\rm{GeV}$, 44.5~$\rm{pb}^{-1}$ of data accumulated at 3.65~$\rm{GeV}$ and data accumulated during a $\psi(3770)$ line-shape scan with the BESIII detector, the reaction $e^+e^-\rightarrow p\bar{p}$ is studied considering a possible interference between resonant and continuum amplitudes. The cross section of $e^+e^-\rightarrow\psi(3770)\rightarrow p\bar{p}$, $\sigma(e^+e^-\rightarrow\psi(3770)\rightarrow p\bar{p})$, is found to have two solutions, determined to be ($0.059\pm0.032\pm0.012$) pb with the phase angle $\phi = (255.8\pm37.9\pm4.8)^\circ$ ($<$0.11 pb at the 90% confidence level), or $\sigma(e^+e^-\rightarrow\psi(3770)\rightarrow p\bar{p}) = (2.57\pm0.12\pm0.12$) pb with $\phi = (266.9\pm6.1\pm0.9)^\circ$ both of which agree with a destructive interference. Using the obtained cross section of $\psi(3770)\rightarrow p\bar{p}$, the cross section of $p\bar{p}\rightarrow \psi(3770)$, which is useful information for the future PANDA experiment, is estimated to be either ($9.8\pm5.7$) nb ($<17.2$ nb at 90% C.L.) or $(425.6\pm42.9)$ nb

Amino-functionalized mesoporous silica based polyethersulfone-polyvinylpyrrolidone composite membrane for elevated temperature fuel cells

© 2016 The Electrochemical Society. Inorganic-organic nanostructured hybrid membranes based on polyethersulfone (PES)-polyvinylpyrrolidone (PVP) were prepared with mesoporous silica materials. All the hybrid membranes showed the similar phosphoric acid (PA) uptake. However, the proton conductivity of the PA-PES-PVP membrane was significantly increased after the addition of the inorganic fillers, especially for the amino-functionalized hollow mesoporous silica (NH2-HMS). The cell performance test also confirmed the superiority of the PES-PVP membranes with the inorganic fillers. The highest peak power density at 180 oC reached up to 480 mW cm-2 for the NH2-HMS based composite membrane fuel cell, which is 92.7 % higher than that of the PA-PES-PVP membrane fuel cell at the identical condition. The outstanding performance of the inorganic-organic hybrid membranes might be due to the facilitated proton transportation in the ordered mesoporous channels, and the great water retention of the inorganic fillers