The broad-spectrum and widely used fungicide pyraclostrobin is encapsulated using a coordination assembly between Fe 3+ and tannic acid to promote its efficacy and environmental safety. The deposition is confirmed by the surface zeta potential and energy dispersive spectroscopy. Optical microscopy, scanning electron microscopy, transmission electron microscopy (TEM), and atomic force microscopy (AFM) observations are integrated to characterize the pyraclostrobin-loaded microcapsules (MCs). These MCs retain a spherical shape when suspended in water but quickly deform or rupture after the water evaporates when deposited for 1 cycle. After sequential deposition of the membrane, the membrane thickness increases linearly according to TEM and AFM height analyses. These MCs show satisfactory efficacy on rice blast, resulting in significantly higher yields at doses of 120 and 180 g ha −1 . Moreover, these MCs display significantly lower toxicity to Brachydanio rerio, Daphnia magna, Xenopus laevis, and Rana nigromaculata. Overall, this novel microencapsulation strategy is capable of promoting the efficacy and environmental safety of pyraclostrobin.

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A chitosan resin derivatized with 3,4-dihydroxybenzoic acid moiety (CCTS-DHBA resin) was newly synthesized for the collection/concentration of trace uranium by using cross-linked chitosan (CCTS) as base material, and the adsorption behavior of uranium as well as 60 elements on the resin was examined by passing the sample solutions through a mini-column packed with the resin. After the elution of the collected elements on the resin with 1 M HNO 3 , the eluates were measured by inductively coupled plasma-mass spectrometry (ICP-MS).The CCTS-DHBA resin can adsorb several metal cations and several oxoanionic elements at appropriate pH. Among these metal ions, uranium shows an excellent adsorption behavior on this resin. Uranium as UO 2 2+ species can be adsorbed on the resin by chelating mechanism with adsorption capacity of 330 mg g -1 resin. Through the column treatment, the complete removal of large amounts of alkali and alkaline earth matrices without any loss of adsorption efficiency over prolonged usage were achieved with this resin.The CCTS-DHBA resin was applied to the adsorption/collection of uranium in tap water, river water and seawater samples with satisfactory results. The validation of the proposed method was carried out by analyzing uranium in the standard reference materials of SLRS-4, CASS-4, and NASS-5 after passing through the CCTS-DHBA resin, and the results showed good agreement with the certified values.

Because of the water swelling of graphene oxide (GO) membranes, the rejection of metal ions is generally low, especially for monovalent metal cations. We prepared a thermally reduced graphene (TrGO) membrane with excellent separation performance of water and NaCl by heat treating GO membranes. Its blocking ability for Na+ is 1529 times larger than that of the GO membrane with the same amount of GO, and it is also much better than the reduced GO membranes prepared by NH3 or HI reduction. Using 3 M sucrose as the draw solution, the 795 nm thick TrGO membrane has an ultrahigh rejection of more than 99.56% for Na+ and maintains a water flux of 0.42 L m–2 h–1. TrGO membranes maintain high stability during the penetration of a high-concentration salt solution, and they have good mechanical properties to maintain operational stability and can be used for a longer time. We characterized and analyzed the separation mechanism of the TrGO membranes and believe that the inner channels form three zones with different hydrophobicity and uniform distribution. The ratio of the three zones can be changed by adjusting the heat-treatment temperature, the duration to swelling force, and the π–π attraction force.

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Global navigation satellite system (GNSS)-reflectometry is a type of remote sensing technology and can be applied to soil moisture retrieval. Until now, various GNSS-R soil moisture retrieval methods have been reported. However, there still exist some problems due to the complexity of modeling and retrieval process, as well as the extreme uncertainty of the experimental environment and equipment. To investigate the behavior of bistatic GNSS-R soil moisture retrieval process, two ground-truth measurements with different soil conditions were carried out and the performance of the input variables was analyzed from the mathematical statistical aspect. Moreover, the feature of XGBoost method was utilized as well. As a recently developed ensemble machine learning method, the XGBoost method just emerged for the classification of remote sensing and geographic data, to investigate the characterization of the input variables in the GNSS-R soil moisture retrieval. It showed a good correlation with the statistical analysis of ground-truth measurements. The variable contributions for the input data can also be seen and evaluated. The study of the paper provides some experimental insights into the behavior of the GNSS-R soil moisture retrieval. It is worthwhile before establishing models and can also help with understanding the underlying GNSS-R phenomena and interpreting data.

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