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Extracting uranium from seawater is an important guarantee for the sustainable development of nuclear energy. Rapid uranium extraction material has short adsorption cycle, which can reduce biofouling and aging to give long service life. Therefore, optimizing adsorption cycle can obtain higher uranium extraction efficiency and economic benefits. Herein, a conjugated mesoporous polymer(CMPAO) was developed for monitorable rapid uranium extraction from seawater using aggregationinduced emissionactive triphenylamine and amidoxime modified fluorene moieties. Uranyl ions can be captured by amidoxime group to enhance the electrochemiluminescence(ECL) signal of CMPAO via resonance energy transfer mechanism, which can be applied in uranyl adsorption monitoring to improve adsorption process. The adsorption of CMPAO in uranyl solution(5×10-5 mol/L) can reach equilibrium within 20 minutes with a capacity of 1825 mg/g. In real seawater, the adsorption process can be completed in 3 days, and the adsorption capacity for U reaches 16 mg/g. As the uranium adsorption increases, the ECL signal can be enhanced gradually, which can be employed in monitoring the adsorption process rapidly.

Antibacterial and oxygen barrier films were inventively prepared by blending very small loadings (<2 wt%) of chitosan oligosaccharide (COS) or chitosan (CS) in thermoplastic starch (TPS) and/or processing with supercritical carbon dioxide (scCO2). Oxygen transmission rates (OTR) and free-volume-hole (FVH) characteristics of scCO2-processed TPS/COS and TPS/CS blown films diminish to a minimum, as their COS or CS approach a specific compatibility limit content. The minimum OTR and FVH characteristics of scCO2-processed TPS/COS films are somewhat smaller than those of corresponding TPS/COS films without scCO2-assistance, and decrease further with decreasing COS molecular weights. The minimum OTR values of scCO2-processed TPS/COS blown films with COS's molecular weight of 200 and 500 are only 4.1 and 4.5 cm3/m2 × day × atm, respectively, and their antibacterial rates of Staphylococcus aureus are ≥97 %, which make them as promising antibacterial and oxygen barrier films having OTR ≦ 5 cm3/m2 × day × atm. Among other things, longitudinal or transversal tensile strengths acquired for the properly scCO2-processed TPS/COS or TPS/CS films are ∼30 to ∼50 % higher than those of the TPS films. Dynamic mechanical relaxation results of these scCO2-processed reveal that chitosan oligosaccharide or chitosan are compatible with TPS, as COS or CS contents are ≤ the compatibility limit value. [ABSTRACT FROM AUTHOR]

In this article, we study the optimal control of stochastic differential equations with random impulses. We optimize the performance index and add the influence of random impulses to the performance index with a random compensation function. Using the idea of stochastic analysis and dynamic programming principle, a new Hamilton–Jacobi–Bellman (HJB) equation is obtained, and the existence and uniqueness of its viscosity solution are proved. [ABSTRACT FROM AUTHOR]

Excellent oxygen barrier films were prepared by blending very small loadings (<1 wt%) of dihydroxyacetone (DHA), erythritol (ET) or xylitol (XT) in thermoplastic starch (TPS), and/or processing with supercritical carbon dioxide (scCO2) assistance. The minimum oxygen transmission rates (OTR) and all free-volume-hole characteristic (FVH) values of each scCO2-processed TPS/sugar alcohol film series are somewhat smaller than those of corresponding TPS/sugar alcohol film series without scCO2-assistance, and decrease with the decrease in sugar alcohol's molecular weight. The minimum OTR values acquired for scCO2-processed TPS/DHA and TPS/ET blown films are only 3.6 and 4.3 cm3/m2·day·atm, respectively, which meet the demand of high oxygen barrier films having OTR ≦5 cm3/m2·day·atm. The longitudinal or transversal tensile strengths acquired for each scCO2-processed TPS/sugar alcohol series films are ∼30 % to ∼40 % higher than those of the TPS blown films. Dynamic mechanical relaxations of each TPS/sugar alcohol or scCO2-processed TPS/sugar alcohol film series reveal that the sugar alcohols are compatible with TPS, as their sugar alcohol contents are ≤ the corresponding compatibility values. The decreased OTR and FVH values acquired for TPS/sugar alcohol or scCO2-processed TPS/sugar alcohol films are most likely due to them being scCO2-processed or incorporated with smaller molecular weight of sugar alcohols. [ABSTRACT FROM AUTHOR]

Knowledge of the spatial and temporal variations in soil nutrients is crucial for designing efficient site-specific nutrient management plans, which can improve crop yields and maximize nutrient use efficiency. The present study was conducted to evaluate and compare the status and spatio-temporal distribution pattern of available nitrogen (AHN), phosphorus (AP) and potassium (AK) and some selected soil properties [soil pH and soil organic matter (SOM)] in cultivated soils of Southwestern China over a 15-year period (2007–2022). We visualized the correlations among soil properties, AHN, AP and AK and analyzed the spatial structures of these parameters. A total of 3845 topsoil (0–20 cm) samples (3331 in 2007 and 514 in 2022) were collected from the cultivated areas of Jiangjin District, Chongqing, Southwestern China. Soil pH, SOM, AHN and AK showed moderate variability with coefficient of variation (CV) values varying between 10 and 100%, except AP (CV > 100%, high variability). The mean soil pH, SOM, AP and AK in 2022 were significantly higher than those in 2007. AHN was significantly positively correlated with SOM (r = 0.531, p < 0.01 in 2007, r = 0.768, p < 0.01 in 2022) and significantly negatively correlated with soil pH (r = −0.186, p < 0.01 in 2007, r = −0.102, p < 0.05 in 2022). AP was significantly negatively correlated with soil pH (r = −0.075, p < 0.01 in 2007, r = −0.126, p < 0.01 in 2022). AK was significantly positively correlated with SOM (r = 0.164, p < 0.01 in 2007, r = 0.229, p < 0.01 in 2022), ANH (r = 0.131, p < 0.01 in 2007, r = 0.251, p < 0.01 in 2022) and AP (r = 0.145, p < 0.01 in 2007, r = 0.52, p < 0.01 in 2022). The exponential function performed best for the soil properties and all three nutrients, with higher R2 values (0.203 to 0.93 in 2007 and 0.316 to 0.796 in 2022) in both years. The nugget/sill ratios (which varied from 31.58% to 72% in 2007 and from 29.31% to 47.02% in 2022) indicated the moderate spatial dependence of all soil parameters, except AK in 2022 (nugget/sill ratio = 23.81%, strong spatial dependence). During the study period, soil pH, AP and AK increased in the central and northern areas; SOM increased in the northern and southwestern parts; AHN decreased in the central areas. The current study highlighted the change in spatial variability of soil pH, AHN, AP and AK in the study area over 15 years. [ABSTRACT FROM AUTHOR]

Oocyte maturation defect can lead to maternal reproduction disorder. NAMPT is a rate‐limiting enzyme in mammalian NAD+ biosynthesis pathway, which can regulate a variety of cellular metabolic processes including glucose metabolism and DNA damage repair. However, the function of NAMPT in porcine oocytes remains unknown. In this study, we showed that NAMPT involved into multiple cellular events during oocyte maturation. NAMPT expressed during all stages of porcine oocyte meiosis, and inhibition of NAMPT activity caused the cumulus expansion and polar body extrusion defects. Mitochondrial dysfunction was observed in NAMPT‐deficient porcine oocytes, which showed decreased membrane potential, ATP and mitochondrial DNA content, increased oxidative stress level and apoptosis. We also found that NAMPT was essential for spindle organization and chromosome arrangement based on Ac‐tubulin. Moreover, lack of NAMPT activity caused the increase of lipid droplet and affected the imbalance of lipogenesis and lipolysis. In conclusion, our study indicated that lack of NAMPT activity affected porcine oocyte maturation through its effects on mitochondria function, spindle assembly and lipid metabolism. [ABSTRACT FROM AUTHOR]