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Due to the poor controlled release ability, bio-based materials are difficult for large scale application on controlled release fertilizers (CRFs). Starch-based polyol (SP) and castor oil (CO) were mutually modified, and a cross-linked polymer film was formed on the surface of urea by in-situ reaction, which improved the slow release ability of the bio-based material. The results showed that increasing the CO ratio reduced porosity of coating and prolonged the nitrogen (N) release period, while the SP changed the high-temperature wrinkle characteristics and regulated the early N release rate. The mutual modification achieved an ultra-long release period of bio-based CRUs for 7 months. The degradation rate during nine months of bio-based coatings (5.05 %) was significantly higher than that of petroleum-based (3.74 %), and the coating was non-toxic to rice seeds. Mutual modification provided a safe and effective solution for the preparation of bio-based CRFs with long-term controlled release capability.The CO2/CO32- chemistry of the cellulose/NaOH(aq) solutions has been recently reported to comprise a CO2 incorporation through formation of a transient cellulose carbonate intermediate along with cellulose - CO32- interactions. This work explores on molecular interactions arising when this chemistry is brought together with urea, the most common stabiliser of these solutions. 1H, 13C and steady-state heteronuclear Overhauser effect NMR studies on the cellulose analogues (methyl-β-glucopyranoside (β-MeO-Glcp) and microcrystalline cellulose), combined with pH and ATR-FTIR measurements, reveal concurrent interactions of urea with both CO2 and CO32-- leading to increased uptake of CO2 and a buffering effect. Yet, regardless of the presence of urea, the route of conversion from CO2 to CO32-, whether going through reaction with the carbohydrate alkoxides or OH-, is likely to determine the chemical environment of the formed CO32-. These findings shed a new light on rather overlooked, albeit prominent, interactions in these solutions with the readily absorbed air CO2, essential for further development and implementation, whether towards regenerated and modified cellulose or CO2-capturing concepts.Silk fibroin (SF) is increasingly needed in tissue engineering for its superior biocompatibility. selleck products However, the practical applications of pure SF biomaterials confront bacterial infection problems. In this study, chitosan (CS) and polydopamine (PDA) were introduced into electrospun nanofibrous SF mats through layer-by-layer self-assembly (LBL) to obtain enhanced antibacterial ability and cytocompatibility. The surface morphology and composition analysis confirmed the successful deposition. After depositing 15 bilayers, the tensile modulus of the mats in wet condition increased from 2.16 MPa (pristine SF mats) to 4.89 MPa. A trend towards better hydrophilicity performance was also recorded with more bilayers coating on the mats. Besides, LBL structured mats showed improved antibacterial ability of more than 98 % against E. coli and S. aureus. In addition, advancement in biocompatibility was observed during the proliferation experiment of L929 cells. Overall, the deposition of CS and PDA may further expand the use of SF in biomedical field.This study evaluates the effects of potassium sulfate (K2SO4) on the swelling, gelatinization, and pasting properties of indica rice starch (IRS), japonica rice starch (JRS), and waxy rice starch (WRS). As a result, the gelatinization temperatures (Tp), swelling capacities, and pasting viscosities of rice starches in water followed the order of WRS > JRS > IRS, showing positive correlations to amylopectin content and molecular weight. At K2SO4 concentration of 0.05-0.6 M, Tp increased by 10-13 ℃ due to a more compact structure of starch granules resulting from increased interactions of starch chains with K+. However, the swelling capacity decreased with increasing K2SO4 concentration and followed the order of WRS less then JRS less then IRS, which decreased sharply from 27.3 to 2.5 g/g for WRS. K2SO4 dramatically reduced the pasting viscosity of starch pastes due to the decreased swelling capacity. This study provides the scientific basis for rice starch processing with K2SO4.We describe a method for permitting efficient modification by transglucosidase (TGA), from glycoside hydrolase family 31 (GH31), sequentially after the pre-treatment by maltogenic α-amylases (MA) from GH13. TGA treatment without MA pre-treatment had negligible effects on native starch, while TGA treatment with MA pre-treatment resulted in porous granules and increased permeability to enzymes. MA→TGA treatments lead to decreased molecular size of amylopectin molecules, increased α-1,6 branching, and increased amounts of amylopectin chains with the degree of polymerization (DP) less then 10 and decreased amounts of DP 10-28 after debranching. Wide-angle X-ray scattering (WAXS) data showed a general decrease in crystallinity except for a long term (20 h) TGA post-treatment which increased the relative crystallinity back to normal. MA→TGA treatment significantly lowered the starch retrogradation of starch and retarded the increase of storage- and loss moduli during storage. This work demonstrates the potential of sequential addition of starch active enzymes to obtain granular starch with improved functionality.Triboelectric nanogenerators (TENGs) are versatile electronic devices used for environmental energy harvesting and self-powered electronics with a wide range of potential applications. The rapid development of TENGs has caused great concern regarding the environmental impacts of conventional electronic devices. Under this context, researching alternatives to synthetic and toxic materials in electronics are of major significance. In this review, we focused on TENGs based on natural polysaccharide materials. Firstly, a general overview of the working mechanisms and materials for high-performance TENGs were summarized and discussed. Then, the recent progress of polysaccharide-based TENGs along with their potential applications reported in the literature from 2015 to 2020 was reviewed. Here, we aimed to present polysaccharide polymers as a promising and viable alternative to the development of green TENGs and tackle the challenges of recycling e-wastes.