Functionalized pristine graphite nanoplatelets (fGNPs) by methanesulfonic acid/isopropyltrioleictitanate (MSA/NDZ-105) are used to fabricate fGNPs/polyphenylene sulfide (fGNPs/PPS) composites by mechanical ball milling followed by a compression molding method.

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The effects of in-situ immobilization of heavy metals by applying natural and chitosan-introduced zeolite, bentonite, and activated carbon (AC) were systematically studied to remediate cadmium (Cd)-contaminated soils in a pot experiment using Brassica juncea as the indicator plant. The results show that zeolite, bentonite, and its chitosan composites can increase soil pH and reduce the biological effectiveness of heavy metals. The Brassica juncea dry weight increased with increasing of amendment dosage. Highest values were found for CS-AC, followed by CS-bentonite, CS-zeolite, AC, bentonite, and zeolite. With an amendment dosage of 75 g per pot, Brassica juncea dry weight increased by 41.91%, 39.

In this study, Fe(III)-cross-linked chitosan beads (Fe(III)-CBs) were synthesized and employed to explore the characteristics and primary mechanism of their hexavalent chromium (Cr(VI)) adsorption under low concentration Cr(VI) (less than 20.0 mg l−1) and a pH range from 2.0 to 8.0. Batch tests were conducted to determine the Cr(VI) adsorption capacity and kinetics, and the effects of pH and temperature on the adsorption under low concentration Cr(VI) and a pH range from 2.0 to 8.0. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy were employed to explore the characteristics of Fe(III)-CBs and their Cr(VI) adsorption mechanisms. The results show that, unlike the adsorption of other absorbents, the Cr(VI) adsorption was efficient in a wide pH range from 2.0 to 6.0, and well described by the pseudo-first-order model and the Langmuir–Freundlich isotherm model. The capacity of Cr(VI) adsorption by Fe(III)-CBs was as high as 166.3 mg g−1 under temperature 25°C and pH 6.0. The desorption test was also carried out by 0.1 mol l−1 NaOH solution for Fe(III)-CBs regeneration. It was found that Fe(III)-CBs could be re-used for five adsorption–desorption cycles without significant decrease in Cr(VI) adsorption capacity. Ion exchange was confirmed between functional groups (i.e. amino group) and Cr(VI) anions (i.e. CrO42−). The amino-like functional groups played a key role in Cr(VI) distribution on the Fe(III)-CBs surface; Cr(VI) adsorbed on Fe(III)-CBs was partially reduced to Cr(III) with alcoholic group served as electron donor, and then formed another rate-limiting factor. So, Fe(III)-CBs has a good prospect in purifying low concentration Cr(VI) water with a pH range from 2.0 to 6.0.

Poly(p-phenylene benzobisoxazole) (PBO) fibers were activated by the horseradish peroxidases (HRP) and then treated by 3-Glycidoxypropyltrimethoxysilane (KH-560) to improve the wettability and the interfacial adhesion between PBO fibers and cyanate ester matrix. The chemical compositions of PBO fibers were characterized and analyzed by FTIR and XPS. Surface morphologies of PBO fibers were examined by SEM. The wettability of PBO fibers was evaluated by the dynamic contact angle analysis test. The mechanical properties were evaluated by tensile strength and interfacial shear strength, respectively. The results demonstrated that hydroxyl groups and epoxy groups were introduced onto the surface of PBO fibers during the treatments. These treatments can effectively improve the wettability and adhesion of PBO fibers. The surface free energy of PBO fibers was increased from 31.1 mN/m to 55.2 mN/m, and the interfacial adhesion between PBO fiber and cyanate ester resin was improved to 10.77 MPa. V C 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40204.