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To collect permeability data and establish its database of fertilizer nutrients and water vapor through different polymer membranes for the development of polymer-coated fertilizer, the permeabilities of N-, P-, and K-nutrient from saturated aqueous of urea, NaH2PO4 and KCl solution and the permeability of water vapor through the membranes of poly lactic acid (PLA), its blends with polystyrene (PS), and its composites with humic acid (HA) particles were determined experimentally at the temperatures of 288, 298, and 308 K, respectively. The effects of the addition of PS and HA particles, temperature, and coating thickness on the permeability of fertilizer nutrient and water vapor were investigated. It was found that the addition of PS and HA increased the permeability for both the fertilizer nutrients and water vapor. The increase in temperature raised the permeability of N-, P-, and K-nutrient while decrease the permeability of water vapor in the range studied.

With the polymer-coated fertilizer as background, the permeability of P- and K-nutrient through a representative polymer membrane-polystyrene membrane were investigated by measuring their permeability in the solutions of KH2PO4-water and urea-KH2PO4-water at nominal temperature of 298 K using the Ussing chamber method. To analyze and interpret the variation of permeability with solute concentration, the solubility of permeate in polymer membrane were determined experimentally and the permeate diffusion coefficient were assessed by the measurements of density and apparent molar volume of the aqueous fertilizer solutions. An interesting “increase-decrease” trend for the permeability of both phosphorous (P)-nutrient, and potassium (K)-nutrient fertilizer with permeate concentration was observed, in which the increases in permeability at low concentrations of permeate could be attributed to the increase in solubility of KH2PO4 in polymer while the decreases in permeability at high concentrations was due to the decrease in diffusion coefficient of permeate in polymer membrane. Finally, the release kinetics of these nutrients from a PS-coated urea-KH2PO4 compound fertilizer granule was predicted using the Shaviv’s model along with the permeability data of P- and K-nutrient generated.

Gamma-phase cesium lead tri-bromide perovskite nanocrystals (γ-CsPbBr3 NCs) possess potentially photo-catalytic degradation ability and long-term stability. However, their serious aggregation issue decreases their active surface area, and the recombination of photo-generated hole–electron pairs weakens their photo-catalytic property. Furthermore, these NCs can be easily absorbed on the surface of dyes [e.g., methylene blue (MB)] or dissolved in the dye solution during the photo-catalytic degradation process, thus reducing the amount of γ-CsPbBr3 NCs and their photo-catalytic degradation ability. Besides, the residual γ-CsPbBr3 NCs in the photo-catalytic degradation products also present the toxicity issue (containing Pb) and are hazardous to the ecological environment and human health. In the present study, we fabricated γ-CsPbBr3 NCs/polymethyl methacrylate electrospun nanofibrous membranes (γ-CsPbBr3 NCs/PMMA ENMs) by using electrospinning technology to solve the above problems. It is found that the synthesized γ-CsPbBr3 NCs/PMMA ENMs show a large surface area and the abundant functional groups on their surfaces, which are benefit for forming multiple kinds of chemical bonding effect between γ-CsPbBr3 NCs and PMMA ENMs. In addition, γ-CsPbBr3 NCs could disperse homogeneously in or on the surface of PMMA ENMs. These abundant chemical bonds and homogeneous distributions of γ-CsPbBr3 NCs on the surface of PMMA ENMs can significantly decrease the recombination of photo-generated hole–electron pairs and toxicity issue of γ-CsPbBr3 NCs during the photo-catalytic degradation process. Exhilaratingly, γ-CsPbBr3 NCs/PMMA ENMs could maintain a superior photo-catalytic degradation ability toward various dyes and reveal a high photo-catalytic degradation efficiency of 99.18% in 60 min for MB. [ABSTRACT FROM AUTHOR]

Multiple studies have investigated the association of interleukin-6 (IL-6) gene polymorphisms and osteoarthritis (OA) risk, but failed to reach a consistent conclusion. Therefore, this study was designed to elucidate the association of IL-6 polymorphisms and OA by a meta-analysis approach. Literature retrieval was carried out on PubMed, EMBASE, Web of Science, CNKI, and Wanfang databases. The strength of association was appraised by odds ratios (ORs) and 95% confidence intervals (95%CIs) in five genetic models. The data were merged by using RevMan 5.3 software. Ten studies with 4944 cases and 4651 controls were analyzed. Overall, no significant association was identified between rs1800795 polymorphism and OA. Subgroup analysis by ethnicity and OA site also suggested rs1800795 polymorphism was not associated with OA. For rs1800796 polymorphism, G-allele and GG-genotype carriers appeared to have an increased risk to OA (G vs. C, OR = 1.66, 95%CI 1.30-1.96, P < 0.01; GG vs. CC, OR = 1.75, 95%CI 1.07-2.84, P = 0.03; GG vs. GC + CC, OR = 1.82, 95%CI 1.42-2.34, P < 0.01). Findings of this study indicate that the rs1800795 polymorphism is not correlated to OA susceptibility, regardless of ethnicity or OA site. However, rs1800796 polymorphism trends to be associated with susceptibility to OA. [ABSTRACT FROM AUTHOR]

Cotton fiber is favored by people because of its good moisture absorption, heat preservation, soft feel, comfortable wearing and other excellent performance. In recent years, due to the destruction of the ozone layer, the intensity of ultraviolet radiation at ground level has increased. Cotton fiber will degrade under long time ultraviolet irradiation, which limits the outdoor application of cotton fiber. In this study, titanium dioxide (TiO2) particles were prepared on the surface of cotton fibers with the help of supercritical carbon dioxide (SCCO2) to improve the UV resistance of cotton fibers. The effects of SCCO2 treatment on the morphology, surface composition, thermal stability, photostability and mechanical properties of TiO2 were studied by Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, thermogravimetric analysis, UV-VIS spectroscopy, and single fiber test. The results showed that TiO2 particles were generated on the fiber surface, which reduced the photo-degradation rate of cotton fiber. This is because TiO2 can absorb UV rays and reduce the absorption of UV rays by the cotton fiber itself. The synthesis process of SCCO2 is simple and environmentally friendly, which provides a promising technology for the synthesis of metal nitrogen dioxide on natural plant fibers. [ABSTRACT FROM AUTHOR]