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Uranium, a double-edged sword with high-efficiency energy and radioactive toxicity, attracts people to enjoy the advantages by generating power, but at the same time brings potential harm by nuclide migration. Therefore, it is necessary to develop a highly-efficient sensor to monitor uranyl ions in the field. However, the designed processes of the reported sensors are random, time-consuming and difficulty. It is urgent to find a new strategy to rationally, quickly and effectively screen out the required molecule for efficient uranium detection. Herein, with the guidance from the rational design method, the parameter, E gap , was applied to judge the chromatic aberration between the designed PADAP derivate and its uranyl complex. And the optimized structure sensor, 2-((3-bromo-5-(9,9-dioctyl-7-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-fluoren-2-yl)-2-pyridylazo)-5-(diethylamino)phenol (abbr. W1H), was screened and successfully synthesized. W1H exhibited significant color change (red to blue) after binding uranyl ions, and its detection limit for uranium was as low as nanomolar. More meaningfully, the coordination mechanism of W1H toward uranium was clarified by theoretical calculation of the electron cloud density distribution, E bind , and 1H NMR, IR and MS for the first time. With the more excellent uranyl sensitivity, selectivity, and recyclability, W1H and its colorimetric test strip have been applied to the detection of low-concentration uranium in environmental samples around the uranium tailings, providing a useful on-site method to monitor trace uranium in actual samples. Image 1 • A high selective and sensitive uranyl sensor named W1H was screened and synthesized with the help of rational design strategy. • The W1H detection limit by UV spectrophotometry was as low as nanomolar level, which was superior to the most reported colorimetric/UV sensors. • The binding mode of uranyl-W1H were identified by DFT calculation of the electron cloud density distribution, 1H NMR, IR and MS for the first time. • Stability constants of interfering metal ion toward W1H shows the reason why W1H can specifically recognize uranium than the other metal ions. • W1H and its colorimetric test strip has been applied to detect uranium in real sample, providing a useful method to detect contaminants in environment. [ABSTRACT FROM AUTHOR]

With rapid development of nuclear industry, the overexploitation of uranium has brought a series of radioactive pollution problems to water, soil, atmosphere and ecosystem. Uranium and its compounds are highly carcinogenic and biologically toxic, posing a deadly threat to human health. Therefore, how to design a highly selective and sensitive sensor to detect uranyl ions in the environment and organisms has become an urgent task. This review summarizes relevant literature on the detection of uranyl ions by different sensors over the years. The detection methods can be roughly divided into three categories: optical sensors, electrochemical sensors and other sensors; further classification has also been carried out according to their detection mechanism. The detection limits and performances of different sensors are discussed to intuitively understand different capability for these methods in detecting uranyl ions. We also discuss the trend and future direction of uranium to provide a valuable reference for further developing better uranyl sensors. Schematic diagram of sensors for detecting uranyl ions by different sensing modes. Image 1 • All of the reported uranium sensors over the years are summarized according to the sensing mode and detection mechanism. • The factors of selectivity, sensitivity, pH and other performance in uranium sensors are reviewed. • Advantages and limitations of uranium sensors in different sensing mode are concluded. • Summarization and future expectation of the uranium sensor are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Hydrophilic, fluorescent hybrid nanoprobes (NDI@HNPs) encapsulated with the hydrophobic pH-responsive fluorophore (N,N′-di-n-dodecyl-2,6-di(4-methyl-piperazin-1-yl)naphthalene-1,4,5,8-tetracarboxylic acid diimide, NDI) for recognizing and mapping the route of cell phagocytosis have been fabricated based on the self-assembly of amphiphilic diblock copolymer PS-b-PAA and the subsequent shell cross-linking with 3-mercaptopropyltrimethoxy silane (MPTMS). The as-synthesized NDI@HNPs has a typical spherical morphology of 46 nm in diameter with excellent monodispersity in aqueous solution. The NDI@HNPs probe exhibits extremely low cytotoxicity, fast real time pH response and enhanced fluorescence intensity under acidic environment with respect to the corresponding free dye in highly polar aqueous system because of the encapsulation of NDI molecules inside nanoparticle cores with weak polarity environment. The fluorescence intensity of NDI@HNPs is enhanced by 55-fold upon changing from neutral (pH = 7.4) or basic (pH = 8.4) to acid (pH = 3.4) in aqueous system, in contrast to the serious fluorescence quenching of free NDI in the same medium, which can exactly meet the physiological pH range in cells. The favorably long emission wavelength is beneficial to the low scattering and minimal interfering requirements to fluorescent bioimaging. Moreover, functionalization with rapid cell-penetrating peptides (HIV-1 TAT) allows them to overcome the physiological and biological barriers during the phagocytosis process. Its characteristic fluorescent response to pH benefits the intracellular labeling and organelle targeting, realizing the real time tracking of the probe entry into cancer cells, the accumulation into the endolysosome and the further escape. [Copyright &y& Elsevier]

• Hydrophobic/hydrophilic bifunctional adsorbent beads were synthesized. • Good adsorption capacity for both sulfamethoxazole and bisphenol A was achieved. • The adsorption kinetics were comprehensively studied. • The adsorbent exhibited excellent reusability. Powdered activated carbon embedded chitosan-polyvinyl alcohol composite (PAC/CS/PVA) beads were designed via a simple method for the adsorptive removal of hydrophilic sulfamethoxazole (SMX) and hydrophobic bisphenol A (BPA) from water. The as-prepared hydrogel was characterized, and the adsorption performances were comprehensively investigated. The maximum adsorption capacities of SMX and BPA on the adsorbent are 9.1 mg g−1 and 64.6 mg g−1, respectively. The optimal pH was around 4 for SMX and 2–9 for BPA, respectively. Higher adsorbent dosages benefited the removal efficiencies but lowered the adsorption capacities. Both temperature and ionic strength slightly affect the adsorption of SMX and BPA. Pseudo-second-order model can well describe the adsorption of SMX and BPA on the hydrogel through spontaneous and endothermic process. Langmuir isotherm model performed better than Freundlich model to fit the equilibrium data. The stable adsorption capacities of SMX and BPA after used the hydrogel for 5 cycles evidenced its excellent reusability. The high adsorption capacities (> 7 mg g−1 for SMX, > 50 mg g−1 for BPA) in the presence of typical water matrices including Cl−, SO 4 2−, Cu2+ and humic acid further suggest the good application potential of the fabricated PAC/CS/PVA beads. [ABSTRACT FROM AUTHOR]

The magnetic poly(N -isopropylacrylamide)/chitosan hydrogel with interpenetrating network (IPN) structure was designed based on the functional groups of targeted emerging contaminants, represented by hydrophilic sulfamethoxazole (SMZ) and hydrophobic bisphenol A (BPA). The average particle size, specific surface area, and total pore volume of the hydrogel were turned out to be 103.7 μm, 60.70 m2/g and 0.0672 cm3/g, respectively. Adsorption results indicated that the maximum adsorption capacity occurred at the pH where SMZ was anionic and BPA was uncharged. When the adsorption temperature increased from 25 °C to 35 °C, the amount of adsorbed SMZ hardly changed, but that of BPA increased by two times. The adsorption capacity of the binary system (i.e., with both SMZ and BPA) was almost the same as that of the single system, indicating that simultaneous adsorption of SMZ and BPA was achieved. The adsorption equilibrium was reached quickly (within 5 min) for both SMZ and BPA. For adsorption isotherm, the Freundlich model fitted well for SMZ at 25, 35 and 45 °C. However, the adsorption of BPA exhibited the sigmoidally shaped isotherm at 25 °C with the Slips model fitting well, and both the Freundlich isotherm and the Slips isotherm fitted the data well at 35 °C and 45 °C, suggesting that the adsorption force was initially weak but greatly enhanced with an increase in adsorbate concentration or ambient temperature. The main adsorption mechanism was inferred to be electrostatic interactions for SMZ, and hydrophobic interactions as well as hydrogen bonding for BPA. The hydrogel adsorbent maintained favorable adsorption capacity for BPA after five adsorption-desorption cycles. These findings may provide a strategy for designing high performance adsorbents that can remove both hydrophilic and hydrophobic organic contaminants in the aquatic environment. Unlabelled Image • The hydrogel adsorbent was designed and synthesized based on the functional groups of the target contaminants. • Good adsorption capacity for both hydrophilic sulfamethoxazole and hydrophobic bisphenol A was achieved. • Electrostatic interactions, hydrophobic interactions and hydrogen bonding dominated the adsorption process. • The adsorbent exhibited good reusability for bisphenol A. [ABSTRACT FROM AUTHOR]

The water intake and water supply pump stations consume a large amount of energy every year, and their energy efficiency improvement has a significant impact on the operations of the water industry. In this study, a general model for simplifying a simulated two-stage system (i.e., water intake and water supply pumping stations) was established. Optimization strategies were developed based on a dynamic-level-feedback-control approach. Non-dominated sorted genetic algorithm-II (NSGA-II) was used to solve the multi-objective optimization problem. Both cost-driven and energy-driven optimizations were proposed from the perspective of reliability, economy, and durability of pumping station operation. Results show that, compared to the extant strategy currently used, the cost- and energy-driven optimization strategies developed in this study can reduce operating energy costs of the system by 7.0% and 6.2%, and have satisfactory stability under the condition of uncertain water demand. Cost-driven optimization improves the power demand response of the two-stage system by increasing the load transfer in peak periods. Energy-driven optimization reduces carbon dioxide emissions by reducing the total operational energy consumption of the system. • A general model of the water intake-supply pump stations is constructed. • Pump switching on/off number and time interval are synthetically considered for the operational durability. • Dynamic-level-feedback-control approach helps to ensure the operational reliability of the two-stage system. • Load transfer and energy consumption are conducive to enhancing system operational energy efficiency. [ABSTRACT FROM AUTHOR]

In view of the few reports of the near-infrared emissive probe for fluorine ions, we herein designed and synthesized a new easy-to-get colorimetric and near-infrared emissive fluorescent probe (IS-NR-F) with a large Stokes shift (>127 nm). Based on specific F− triggered desilylation reaction induced enhanced ICT strategy involving the donor phenolate anion and the acceptor malononitrile, the probe exhibited dual colorimetric and fluorescent turn-on responses, and provided excellent selectivity for fluoride ions. The fluorescent response at 665 nm displayed very good linear relationship in the wide concentration range and deduced a low detection limit of 0.09 ppm. The detection mechanism was confirmed by 1H NMR, ESI-MS, and TLC calculation. Moreover, probe IS-NR-F has been successfully employed to detect F− in tap water, toothpaste samples, and fluorescent imaging of F− in HeLa cells. Image 1 • A new dicyanoisophorone derived near-infrared fluorescent probe was synthesized with a large Stokes shift (127 nm). • The probe performed an excellent selectivity for F− by naked eyes. • The probe exhibited a wide detection range with a good linear relationship for F−. • The probe was applied to detect F− in toothpaste samples and imaging in living cells. [ABSTRACT FROM AUTHOR]