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The Coats-Redfern method is commonly used to calculate the activation energy of the thermal degradation from a single non-isothermal thermogravimetric curve since its first proposal in 1964. This paper represents the accurate expressions, sound derivation process and proper usage of the Coats-Redfern equations, based on the critique into the Coats-Redfern's original article, Djalal Trache's incorrect comments on Reza Arjmandi et al.'s article, and the flaw in Reza Arjmandi et al.'s work per se., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Flexible plasmonic Surface-enhanced Raman scattering (SERS) substrates were fabricated using cellulose textile fibers, in which the textile fibers were recycled from waste paper in an eco-friendly way. The Glycidyltrimethylammonium chloride (GTAC) with positive charges was grafted onto the surface of the cellulose textile fibers through cationization. Plasmonic silver nanoparticles (Ag NPs) with negative charges were decorated onto the cellulose textile fibers via electrostatic interactions. After cationization, the variation range of the diameter of the cellulose textile fibers was significantly increased because part of the cellulose was dissolved under alkaline condition, leading to more 'hot spots' for SERS during the shrinking process. The cellulose textile fiber-Ag NPs nanocomposite was employed for monitoring bisphenol A (BPA) in water and soft drink by SERS and the sensitivity of BPA detection achieved 50 ppb. The recovery values of BPA in soda water samples were from 96% to 105%. These results illustrate that the cellulose textile fiber-Ag NPs nanocomposite can be used as flexible, high sensitivity SERS substrates for detecting harmful ingredients in food or environment., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Cellulose derivatives functionalized with multidentate N‑donor atoms containing two, three and four amino functional groups (as marked N2–CL, N3–CL and N4–CL) have been prepared by grafting of linear aliphatic polyamines into the cellulose backbone through the Schiff base reaction. An increase in the adsorptive amounts of Cd2+ and Pb2+ with increasing N‑donor atoms of the grafted polyamines onto the cellulose backbone and the maximum capacity of N4–CL > N3–CL > N2–CL are found. The N4–CL with the highest N content (up to 5.2 mmol N g−1) exhibits the largest adsorptive capacities of 249.7 mg g−1 for Cd2+ and 401.2 mg g−1 for Pb2+. The adsorption of both the ions by the three cellulose derivatives is achieved within 30 min, is independent of pH in the range of 4.5–6 for Cd2+ and 4–6 for Pb2+, and can be satisfactorily fitted by Langmuir and pseudo-second-order equations. Thermodynamic parameters suggest an endothermic and endothermic nature. [ABSTRACT FROM AUTHOR]

Cellulose, a regenerative superior material, has been attracted an increased interest for extending its area to use. Here, some chelating celluloses functionalized with four amino acids: cysteine, histidine, aspartic acid, and methionine (as named Cys-CL, His-CL, Asp-CL and Met-CL) were prepared through a Schiff base reaction, and analyzed by several means of characterization for the purpose of enhanced adsorptive removal of Cd2+ and Pb2+ from aqueous solution. For the Cd2+ ions, the saturated adsorptive capacities of the Cys-CL, His-CL, Asp-CL and Met-CL at 30 °C in the optimal pH range of 4.5–5.5 were found to be 130.7, 87.0, 75.5 and 37.1 mg g−1, respectively. For the Pb2+ions, the saturated adsorptive capacities of the Cys-CL, His-CL, Asp-CL and Met-CL at 30 °C in the optimal pH range of 4.0–5.5 were found to be 180.9, 119.0, 111.0 and 51.1 mg g−1, respectively. The results clearly illustrated adsorption capacities conformed to Cys-CL > His-CL > Asp-CL > Met-CL. Cys-CL exhibited the obvious advantages and was sensitive to the initial concentrations of both the metal ions, solution pH and temperature. The rapid uptakes of the Cd2+ and Pb2+ by the Cys-CL were observed within 30 min. The adsorption of both the metal ions by the Cys-CL was described reliably by the Langmuir and pseudo second-order models and occurred spontaneously and endothermically in nature. The Cys-CL with good adsorptive characteristics and recyclability owns great potential for the adsorptive removal of the Cd2+ and Pb2+ from aqueous solution. [Display omitted] • A chelating celluloses with N, O, S-donor atoms facilitated by a Schiff base reaction. • Chelating cellulose functionalized with cysteine with a better adsorptive performance. • Adsorption of both the metal ions pursue Langmuir and pseudo-second-order equations. • Adsorption of both the metal ions is spontaneous and endothermic intrinsically. [ABSTRACT FROM AUTHOR]