Understanding hysteresis in carbon dioxide sorption in porous metal-organic frameworks

Two new isostructural microporous coordination frameworks [Mn3(Hpdc)2­(pdc)2] (1) and [Mg3(Hpdc)2­(pdc)2] (2) (pdc2– = pyridine-2,4-dicarboxylate) showing primitive cubic (pcu) topology have been prepared and characterized. The pore aperture of the channels is too narrow for the efficient adsorption of N2; however, both compounds demonstrate substantially higher uptake of CO2 (119.9 mL·g–1 for 1 and 102.5 mL·g–1 for 2 at 195 K, 1 bar). Despite of their structural similarities, 2 shows a typical reversible type I isotherm for adsorption/desorption of CO2, while 1 features a two-step adsorption process with a very broad hysteresis between the adsorption and desorption curves. This behavior can be explained by a combination of density functional theory calculations, sorption, and X-ray diffraction analysis and gives insights into the further development of new sorbents showing adsorption/desorption hysteresis

Digital spectrometer for prompt fission neutron spectrum measurements

This paper presents a digital neutron spectrometer based on simultaneous digitizing of the signals from the fission chamber and a scintillation detector. The scintillation detector is based on stilbene crystal. The intrinsic detection efficiency of the used stilbene crystal and the energy dependence of the light output for the recoil protons were measured. It is shown, that the method allowed us to achieve time resolution of 1.5 ns and an good n/γ separation down to neutron energies of 400 keV

Digital spectrometer for prompt fission neutron spectrum measurements

This paper presents a digital neutron spectrometer based on simultaneous digitizing of the signals from the fission chamber and a scintillation detector. The scintillation detector is based on stilbene crystal. The intrinsic detection efficiency of the used stilbene crystal and the energy dependence of the light output for the recoil protons were measured. It is shown, that the method allowed us to achieve time resolution of 1.5 ns and an good n/γ separation down to neutron energies of 400 keV

Digital spectrometer for prompt fission neutron spectrum measurements

This paper presents a digital neutron spectrometer based on simultaneous digitizing of the signals from the fission chamber and a scintillation detector. The scintillation detector is based on stilbene crystal. The intrinsic detection efficiency of the used stilbene crystal and the energy dependence of the light output for the recoil protons were measured. It is shown, that the method allowed us to achieve time resolution of 1.5 ns and an good n/γ separation down to neutron energies of 400 keV