electricity on a large scale with ultralow greenhouse gases emission. [2] Uranium is the most critical ingredient for the production of nuclear power. In order for nuclear power to be a sustainable energy generation in the future, economically viable sources of uranium beyond terrestrial ores must be developed. [3] The oceans hold ≈4.5 billion tons of uranium, [4] making them a potential huge resource to support nuclear power production for hundreds of years. [5] All that is required is the ability to capture this element from seawater in cost-and energy-efficient ways. In the last decades, researchers worldwide have tried various methods to recover uranium from seawater and aqueous solution, such as coprecipitation, [6] ion-exchange, [7] adsorption via porous organic polymers, [8,9] and organic-inorganic hybrid adsorbents. [10][11][12][13][14][15][16] Among these technologies, the adsorption approach, particularly by using fiber-based adsorbents, is recognized as the most feasible process in terms of practicality, processability, cost, and environmental concerns. [3,17] In the 1990s, Japan Atomic Energy Agency (JAEA) research teams had successfully captured over 1083 g of uranium directly from ocean by using nonwoven fabric adsorbent, firmly establishing the practicality of uranium recovery from the oceans in appreciable quantities. [3,18] Uranium extraction from seawater via fiber adsorption has recentlyThe oceans contain hundreds of times more uranium than terrestrial ores. Fiber-based adsorption is considered to be the most promising method to realize the industrialization of uranium extraction from seawater. In this work, a pre-amidoximation with a blow spinning strategy is developed for mass production of poly(imide dioxime) nanofiber (PIDO NF) adsorbents with many chelating sites, excellent hydrophilicity, 3D porous architecture, and good mechanical properties. The structural evidences from 13 C NMR spectra confirm that the main functional group responsible for the uranyl binding is not "amidoxime" but cyclic "imidedioxime." The uranium adsorption capacity of the PIDO NF adsorbent reaches 951 mg-U per g-Ads in uranium (8 ppm) spiked natural seawater. An average adsorption capacity of 8.7 mg-U per g-Ads is obtained after 56 d of exposure in natural seawater via a flowthrough column system. Moreover, up to 98.5% of the adsorbed uranium can be rapidly eluted out and the adsorbent can be regenerated and reused for over eight cycles of adsorption-desorption. This new blow spun PIDO nanofabric shows great potential as a new generation adsorbent for uranium extraction from seawater.

The uranium level in seawater is ≈1000 times as high as terrestrial ores and can provide potential near‐infinite fuel for the nuclear energy industry. However, it is still a significant challenge to develop high‐efficiency and low‐cost adsorbents for massively extracting uranium from seawater. Herein, a simple and fast method through low‐energy consumption sunlight polymerization to direct fabrication of a poly(amidoxime) (PAO) hydrogel membrane, which exhibits high uranium adsorption capacity, is reported. This PAO hydrogel owns semi‐interpenetrating structure and a hydrophilic poly(acrylamide) 3D network of hydrogel which can disperse and fix PAOs well. As a result, the amidoxime groups of PAOs exhibit an outstanding uranium adsorption efficiency (718 ± 16.6 and 1279 ± 14.5 mg g −1 of m uranium / m PAO in 8 and 32 ppm uranium‐spiked seawater, respectively) among reported hydrogel‐based adsorbents. Most importantly, U‐uptake capacity of this hydrogel can achieve 4.87 ± 0.38 mg g −1 of m uranium / m dry gel just after four weeks within natural seawater. Furthermore, this hydrogel can be massively produced through low‐energy consumption and environmentally‐friendly sunlight polymerization. This work will provide a high‐efficiency and low‐cost adsorbent for massive uranium extraction from seawater.

Highly efficient recovery of uranium from seawater is of great concern because of the growing demand for nuclear energy. The use of amidoximebased polymeric fiber adsorbents is considered to be a promising approach because of their relatively high specificity and affinity to uranyl. The surface area, hydrophility, and surface charge of the adsorbent are reported to be critical factors that influence uranium recovery efficiency. Here, a porous amidoxime-based nanofiber adsorbent (SMON-PAO) that exhibits the highest uranium recovery capacity among the existing fiber adsorbents both in 8 ppm uranium spiked seawater (1089.36 ± 64.31 mg-U per g-Ads) and in natural seawater (9.59 ± 0.64 mg-U per g-Ads) is prepared by blow spinning. These nanofibers are obtained by compositing polyacrylamidoxime with montmorillonite and exhibit the increased surface area and more exposed functional amidoxime moieties for uranyl adsorption. The residual montmorillonite enhances the hydrophility and reduces the negative surface charge, thereby increasing the contact of the adsorbent with seawater and reducing the charge repulsion between negative amidoxime group and negative uranyl species ([UO 2 (CO 3 ) 3 ] 4− ). The finding of this study indicates that rational design of uranium recovery adsorbents by comprehensive utilizing the key factors that influence uranium recovery performance is a promising approach for developing economically feasible uranium recovery materials.

The ocean reserves 4.5 billion tons of uranium and amounts to a nearly inexhaustible uranium supply. Biofouling in the ocean is one of the most severe factors that hazard uranium extraction and even cause the failure of uranium extraction. Therefore, development of uranium adsorbents with biofouling resistance is highly urgent. Herein, a strategy for constructing anti‐biofouling adsorbents with enhanced uranium recovery capacity in natural seawater is developed. This strategy can be widely applied to modify currently available carboxyl‐contained adsorbents, including the most popular amidoxime‐based adsorbent and carboxyl metal organic framework adsorbent, using a simple one‐step covalent cross‐link reaction between the antibacterial compound and the adsorbent. The prepared anti‐biofouling adsorbents display broad antibacterial spectrum and show more than 80% inhibition to the growth of marine bacteria. Benefitting from the tight covalent cross‐link, the anti‐biofouling adsorbents show high reusability. The modified amidoxime‐based adsorbents show enhanced uranium recovery capacity both in sterilized and bacteria‐contained simulated seawater. The anti‐biofouling adsorbent Anti‐UiO‐66 constructed in this study exhibits 24.4% increased uranium recovery capacity, with a uranium recovery capacity of 4.62 mg‐U per g‐Ads, after a 30‐day field test in real seawater, suggesting the strategy is a promising approach for constructing adsorbents with enhanced uranium extraction performance.

Airborne dust derived from desertification in northern China can be transported to East Asia and other regions, impairing human health and affecting the global climate. This study of northern China dust provides an understanding of the mechanism of dust generation and transportation. The authors used dust storm and climatological data from 129 sites and normalized difference vegetation index (NDVI) datasets in northern China to analyze spatiotemporal characteristics and determine the main factors controlling dust storms occurring during 1960–2007. Dust storm–prone areas are consistent with the spatial distribution of northern China deserts where the average wind speed (AWS) is more than 2 m s−1, the mean annual temperature (MAT) ranges from 5° to 10°C, and the mean annual precipitation (MAP) is less than 450 mm. Dust storms commonly occur on spring afternoons in a 3- to 6-h pattern. The three predominant factors that can affect DSF are the maximum wind speed, AWS, and MAT. During 1960–2007, dust storm frequency (DSF) in most regions of northern China fluctuated but had a decreasing trend; this was mainly caused by a gradual reduction in wind speed. The effect of temperature on DSF is complex, as positive and negative correlations exist simultaneously. Temperatures can affect source material (dust, sand, etc.), cyclone activity, and vegetation growth status, which influence the generation of dust storms. NDVI and precipitation are negatively correlated with DSF, but the effect is weak. Vegetation can protect the topsoil environment and prevent dust storm creation but is affected by the primary decisive influence of precipitation.