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Geosynchronous orbit environment effects of 15 years on solar absorptance of thermal control coatings such as S781 white paint, SR107-ZK white paint, silvered fluorinated ethylene propylene F46, and optical solar reflectors on the outer satellite are simulated by a combined low-energy irradiation test. Severe degradation is found in organic white paint whereas optical solar reflectors and silvered fluorinated ethylene propylene F46 remains quite stable. By comparison with flight test results, the effectiveness of the simulation method has been shown. Based on the degradation trend data, the least-square regression method was used to obtain an empirical formula. The secondorder exponential decaying formulas are found to be quite good to fit degradation curves of four kinds of materials. Extrapolation for a longer test time has been made, and the results have been verified. The error of using 8 year test results to extrapolate 15 year degradation is verified to be less than 1%. [ABSTRACT FROM AUTHOR]

The purpose of this research is to use a simple method to prepare magnetic modified corncobs (MCBs) with good adsorption performances for Congo Red (CR). The adsorption was analyzed by Fourier transform infrared spectroscopy and x-ray diffraction. The maximal adsorption capacity of the MCB for CR was 198.2 mg/g and about 5.5-fold for unmodified corncob. Potassium ion was more positive effect onto adsorption than sodium ion. The dye uptake process obeyed the pseudo-second-order kinetic expression. The best-fitted data were obtained with the Langmuir model. The as-prepared magnetic modified sorbent had a potential in the dyeing industry wastewater treatment. [ABSTRACT FROM PUBLISHER]

A simple synthesis route for amine protected-introduced-released chitosan (APIR-CS) was investigated to improve the adsorption of anionic dyes. The C2amine groups of the chitosan (CS) were initially protected via a Schiff-base reaction by benzaldehyde. They were then synthesized by the introduction of ethylenediamine into C6hydroxyl groups on CS via epichlorohydrin. The final product was obtained after removal of the Schiff base with dilute hydrochloride solution. Amine-introduced chitosan (AI-CS) was directly synthesized at the C2amine groups. The adsorbents were characterized by FTIR, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). For Congo red (CR) and methyl orange (MO), most of the amine groups in CS were converted to–N˭CH2groups after the benzaldehyde treatment. Hydrochloric acid treatment after the cross-linking reaction released protected nitrogen atoms into the form of the primary amine again. APIR-CS had significantly greater adsorption capacities than AI-CS. The increased adsorption performance was attributed to the large number of primary amine groups on the surfaces. The adsorption mechanism was based on electrostatic interaction, while the adsorption process was mainly physisorption. [ABSTRACT FROM PUBLISHER]

In this paper, rape stalk was modified with citric acid (CA) to prepare copper ion biosorbent. The modified rape stalk (MRS) was characterized by Fourier transforms infrared (FTIR), zeta potential, and thermogravimetric analysis (TGA). The effects of various parameters like initial Cu2+concentration, contact time, initial pH, and temperature on adsorption capacity were studied. The adsorption capacity of MRS at 298 K was 69.84 mg/g, far higher than 18.24 mg/g for native rape stalk (NRS). The adsorption mechanism was also evaluated in terms of kinetics and thermodynamics. The adsorption equilibrium data was well described by the Langmuir isotherm model. The adsorption process followed the pseudo-second-order rate kinetics. Thermodynamic study showed spontaneous and endothermic nature of the adsorption process. The ion exchange of the adsorption mechanism was affirmed. MRS could be a potentially low-cost and green adsorbent for removal of Cu2+from aqueous solution. [ABSTRACT FROM PUBLISHER]