395 research outputs found
Real-time probing electron dynamics of an atom in a strong infrared laser field
We present theoretical studies on real-time probing the electron density
evolution of an atom in a strong infrared (IR) laser field with few-cycle
near-infrared (NIR) and attosecond extreme-ultraviolet (XUV) pulses. Our
results indicate that the electron density near the tunneling barrier is
reflected in the additional tunneling ionization yield with a delayed NIR pulse
and the electron density near the nucleus can be probed by the single
photoionization yield with a delayed XUV pulse. It turns out the NIR-probing
scheme can be used to study the polarization of the system in an external IR
field and the XUV-probing can be additionally applied to explore excitation
dynamics during and after the IR field interaction
Secret underneath:Fouling of membrane support layer in anaerobic osmotic membrane bioreactor (AnOMBR)
A novel forward osmosis reactor assisted with microfiltration for deep thickening waste activated sludge:performance and implication
Waste activated sludge (WAS) treatment has gained growing interests for its increasingly capacity and high process cost. Sludge thickening is generally the first process of the WAS treatment. However, traditional sludge thickening approach was restrained by large footprint, low thickening efficiency, and tendency of releasing phosphorus. Here, we reported a novel microfiltration (MF) membrane assisting forward osmosis (FO) process (MF-FO) for sludge thickening. The MF-FO reactor achieved a sludge thickening of the mixed liquor suspended solids (MLSS) concentration from approximately 7 to 50 g/L after 10-day operation. More importantly, the effluent quality after FO filtration was superior with total organic carbon (TOC), ammonia nitrogen (NH4+-N), nitrate nitrogen (NO3−-N) and total phosphorus (TP) of 1.94 ± 0.46, 0.02 ± 0.07, 4.55 ± 1.59 and 0.24 ± 0.26 mg/L, respectively. Additionally, the integration of MF membrane successfully controlled the salinity of the MF-FO reactor in a low range of 1.6-3.1 mS/cm, which mitigated the flux decline of FO membrane and thus prolonged the operating time. In this case, the flux decline of FO membrane in the MF-FO reactor was mainly due to the membrane fouling. Furthermore, the fouling layer on the FO membrane surface was a gel layer mainly composed of biofoulants and organic foulants when the MLSS concentration was less than 30 g/L, while it turned to a cake layer when the MLSS concentration exceeded 30 g/L. Results reported here demonstrated that the MF-FO reactor is a promising WAS thickening technology for its excellent thickening performance and high effluent quality of FO membrane.</p
Frustrated Double Ionization of Argon Atoms in Strong Laser Fields
We demonstrate kinematically complete measurements on frustrated double
ionization of argon atoms in strong laser fields with a reaction microscope. We
found that the electron trapping probability after strong field double
ionization is much higher than that after strong field single ionization,
especially in case of high laser intensity. The retrieved electron momentum
distributions of frustrated double ionization show a clear transition from the
nonsequential to the sequential regime, similar to those of strong field double
ionization. The dependence of electron momentum width on the laser intensity
further indicates that the second released electron has a dominant contribution
to frustrated double ionization in the sequential regime
In situ extracting organic-bound calcium:A novel approach to mitigating organic fouling in forward osmosis treating wastewater via gradient diffusion thin-films
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