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In this work, hierarchically porous Cu doped Cu2O/reduced graphene oxide/cellulose (Cu@Cu2O/RGO/CE) hybrid catalysts were facilely prepared by in-suit deposition of Cu2O nanoparticles on 3D graphene oxide/cellulose (GO/CE) aerogels. The morphology, structure, optical properties, and photocatalytic performances of the resultant Cu@Cu2O/RGO/CE hybrid catalysts were investigated systematically. GO uniformly dispersed in cellulose matrix and induced the formation of homogeneous GO/CE hydrogels. And highly uniform octahedral Cu doped Cu2O nanoparticles anchored on the pore wall of the GO/CE aerogels without aggregation. The photocatalytic activity of Cu@Cu2O/RGO/CE hybrid catalysts for methyl orange (MO) was 2 times high to that of Cu2O/CE under visible light. This high photocatalytic activity of Cu@Cu2O/RGO/CE hybrid catalysts mainly derived from its specific hierarchical porous structure and hybrid phase compositions which were responsible for enhanced light harvesting, abundant catalytic active sites, excellent mass and electron transfer ability. Moreover, the Cu@Cu2O/RGO/CE hybrid catalysts could easily be recycled from aqueous solution and exhibited superior stability in cycle experiments. The main active species were detected to be. O2−,. OH and holes under visible light irradiation. Thus, this work provides a facile approach for preparing high-efficiency and easy recoverable photocatalysts, but also a promising technology for organic pollutant degradation.

How to charge high-temperature superconducting coils is a crucial problem for superconducting magnets. In recent years, flux pump is recommended as a promising method for current compensation since it can charge coils without electrical contact to current source. In this work, two types of charging methods, rotating magnet based flux pump and magnetically controlled persistent current switch, are discussed experimentally and numerically. Their output characteristics were tested and demonstrated. Charging performance on different types of loads including insulated HTS coil, no-insulation HTS coil and DC current source, is analyzed and compared. Results of this paper will prove the validity of those two charging methods in future superconducting magnet applications.

Novel architectured porous Cu@Cu 2 O hybrid microspheres were successfully designed and synthesized using silk sericin (SS) as structure-director to firstly form the hierarchical Cu 2 O/SS microspheres by self-assembly, followed by a calcination process. A possible mechanism has been proposed based on the results of FESEM, TEM and XRD analysis. The photocatalytic performance of obtained porous Cu@Cu 2 O hybrid microspheres was investigated, and the synergistic effect of Cu and Cu 2 O phases contributed to improving the light absorption ability, electron-hole separation and transfer compared with pure Cu 2 O. Importantly, the photo-degradation ratio of Cu@Cu 2 O hybrid microspheres for methyl orange (MO) reached up to 99.9% after 110 min visible light irradiation, which is almost 1.3 times than that of pure Cu 2 O. Furthermore, Cu@Cu 2 O hybrid microspheres also exhibited outstanding reusability and stability because that its degradation efficiency for MO still maintained at 93.5% after five cycles.

The high-frequency waves-Terahertz (THz) emission from laser-induced air-plasma is presented. The development of high power and high efficiency THz wave radiation source has significant value. The development of laser technology has led spectroscopic sensing and imaging in the THz region to be widely employed in diverse fields such as material characterization, ultrafast dynamic process studies, and biological science. The emission of THz waves has become one of the most important areas in THz research. In this research, we develop an THz time-domain spectroscopy system(THz- TDS), which is that the input laser pulses are generated from a p-polarized regenerative Ti:sapphire amplifier with a 50- fs pulse duration centered at 800 nm. A 100-μm-thick type-I BBO crystal is employed for frequency doubling the pump pulses and subsequently generating the THz wave. By this setup we investigate that when the terahertz emission from only fundamental wave and with second-harmonic wave mixing, the intensity of the terahertz wave obtained is different. The energy of THz wave generated by only fundamental wave is weak, and that generated by four wave mixing is stronger. The energy intensity of THz wave generated by four wave mixing is much higher than that of THz wave generated by fundamental wave (almost an order of magnitude higher). We believe that the different ionization modes causes the different of terahertz wave energy intensity. In addition, we find that the second harmonic wave grows in a quadratic curve with the increase of pump energy, so we believe that when the pump energy increases, the terahertz wave also grows in a quadratic curve.

A green, high-efficiency flocculant based on hyperbranched polyethylenimine-grafted cellulose (hPEI-CE) was designed and successfully synthesized. The flocculation performance of the hPEI-CE with different amino group contents for treating simulated kaolin wastewater was evaluated in terms of turbidity, floc size, and zeta potential. Without the help of any coagulant aid, hPEI-CE with an amino group content of 3.97 mmol/g presented the best removal efficiency for kaolin particles. The residual turbidity of kaolin suspension decreased from original 490 NTU to 4 NTU under the optimized conditions, i.e., 2.4 mg/L of hPEI-CE flocculant at pH 7.0 for 30 min. Furthermore, two types of industrial wastewater were used to investigate the flocculation performance of hPEI-CE: silk printing and dyeing wastewater and machining wastewater. Total suspended solid (TSS), chemical oxygen demand (COD), and turbidity reduction reached up to 73.4%, 95.7%, and 87.4% for silk printing and dyeing wastewater, 96.2%, 79.9%, and 93...