No abstract

No abstract

Chitosan (CS) microspheres were prepared by emulsion crosslinking, and the surfaces of the spheres were modified with poly(ethylenimine) (PEI) for preparing efficient adsorbents. Consequently, a series of PEI-modified CS (CS-PEI) microspheres with different ion exchange capacities (IECs) was prepared and used for the adsorption of methyl orange (MO). The adsorption performance of CS-PEI increased significantly with the increase of the sphere IECs, and the maximum adsorption capacity of 400.00 mg/g was achieved at 303 K with CS-PEI-1275, which had the highest IEC in the experiments. The adsorption process of MO well fitted the pseudo-second-order kinetic and Langmuir isotherm models, and the process was favorable at low temperature. Thermodynamic analyses showed that the adsorption of MO by CS-PEI was a spontaneous and exothermic reaction. Furthermore, CS-PEI exhibited good reusability within seven cycles of adsorption-desorption.

This paper studies the radiation resistance for GaInP/GaInAs/Ge triple-junction space solar cells with a GaInP back-surface field (BSF) in the GaInAs middle subcell compared with those with an AlGaAs BSF. The results show that the initial electrical performance is almost the same for both of them. However, the radiation resistance of the GaInP BSF cell was improved. After irradiation by 1 MeV electron beam with a cumulative dose of 1015 e/cm2, the Jsc declined by 4.73% and 6.61% for the GaInP BSF cell and the AlGaAs BSF cell, respectively; the efficiency degradation was 13.64% and 14.61% for the GaInP BSF cell and the AlGaAs BSF cell, respectively, leading to a reduced degradation level of 6%. The mechanism for GaInP BSF to improve the radiation resistance of GaInP/GaInAs/Ge triple-junction solar cells is also discussed in this work. Similar results were obtained when irradiation cumulative doses varied from 1 × 1014 e/cm2 to 1 × 1016 e/cm2.