5 research outputs found

    Regeneration of Alkanolamine Solutions in Membrane Contactor Based on Novel Polynorbornene

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    For the first time, a novel highly permeable glassy polymer, addition poly[bis(trimethylsilyl)tricyclononene] (PBTMST), was proposed for its use in a gas-liquid membrane contactor for the regeneration of CO2 absorption liquids (desorption of CO2). This membrane material possesses a good chemical stability and high barrier properties for a number of alkanolmines (30 wt% solutions of MEA, DEA, MDEA, AMP, DEAE or AEAE) under typical regeneration conditions (T = 100°C). Studies on gas transport properties of PBTMST (100°C and 1-40 bar) show that permeability coefficients of oxygen, nitrogen and carbon dioxide initially tend to decrease, and then level off after first 6-8 hours of operation. This behavior can be explained by partial relaxation of the free-volume structure of PBTMST, no chemical degradation of polymer material at high temperature was confirmed by IR analysis. At the same time, this membrane material preserves high gas permeability coefficients which are higher than those of conventional materials used in the membrane contactors. Gas-liquid membrane contactor based on dense PBTMST membrane shows a good, stable performance; particularly, CO2 loading in diethanolamine solution (30 wt%) can be reduced for 0.05-0.34 mole/mole by single pass through the membrane desorber at 100°C and elevated pressure. It seems that desorption rate here is mainly controlled by liquid phase because decreasing of membrane thickness by 50% (from 31 to 21 μm) leads to improvement of DEA regeneration only by 1.5-8.5%

    Energy scan of the e+ehb(nP)π+πe^+e^- \to h_b(nP)\pi^+\pi^- (n=1,2)(n=1,2) cross sections and evidence for the Υ(11020)\Upsilon(11020) decays into charged bottomonium-like states

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    Using data collected with the Belle detector in the energy region of the Υ(10860)\Upsilon(10860) and Υ(11020)\Upsilon(11020) resonances we measure the e+ehb(nP)π+πe^+e^- \to h_b(nP)\pi^+\pi^- (n=1,2)(n=1,2) cross sections. Their energy dependences show clear Υ(10860)\Upsilon(10860) and Υ(11020)\Upsilon(11020) peaks with a small or no non-resonant contribution. We study resonant structure of the Υ(11020)hb(nP)π+π\Upsilon(11020) \to h_b(nP)\pi^+\pi^- transitions and find evidence that they proceed entirely via intermediate charged bottomonium-like states Zb(10610)Z_b(10610) and/or Zb(10650)Z_b(10650) (with current statistics we can not discriminate hypotheses of one or two intermediate states).Using data collected with the Belle detector at the KEKB asymmetric-energy e+e- collider, we measure the energy dependence of the e+e-→hb(nP)π+π- (n=1, 2) cross sections from thresholds up to 11.02 GeV. We find clear ϒ(10860) and ϒ(11020) peaks with little or no continuum contribution. We study the resonant substructure of the ϒ(11020)→hb(nP)π+π- transitions and find evidence that they proceed entirely via the intermediate isovector states Zb(10610) and Zb(10650). The relative fraction of these states is loosely constrained by the current data: The hypothesis that only Zb(10610) is produced is excluded at the level of 3.3 standard deviations, while the hypothesis that only Zb(10650) is produced is not excluded at a significant level.Using data collected with the Belle detector at the KEKB asymmetric-energy e+ee^+e^- collider, we measure the energy dependence of the e+ehb(nP)π+πe^+e^- \to h_b(nP)\pi^+\pi^- (n=1,2)(n=1,2) cross sections from thresholds up to 11.0211.02\,GeV. We find clear Υ(10860)\Upsilon(10860) and Υ(11020)\Upsilon(11020) peaks with little or no continuum contribution. We study the resonant substructure of the Υ(11020)hb(nP)π+π\Upsilon(11020) \to h_b(nP)\pi^+\pi^- transitions and find evidence that they proceed entirely via the intermediate isovector states Zb(10610)Z_b(10610) and Zb(10650)Z_b(10650). The relative fraction of these states is loosely constrained by the current data: the hypothesis that only Zb(10610)Z_b(10610) is produced is excluded at the level of 3.3 standard deviations, while the hypothesis that only Zb(10650)Z_b(10650) is produced is not excluded at a significant level

    Electrocatalysis of Hydrogen Evolution: Progress in Cathode Activation

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