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A compact five-element integrated ultrasonic transducer was designed and manufactured for the inspection of defects in the split pins of control rod guide tubes in nuclear power plants. The transducer consists of three types of ultrasonic elements to detect cracks in the entire volume of the split pins. In the transducer design, two main factors were investigated: the coupling of elements in confined space and measurement sensitivity. The experimental results demonstrated that the developed transducer has good acoustic performance and defect response capabilities and can detect 10 mm × 2 mm × 0.5 mm notches in the three areas of the split pins. This work provides a foundation for applications in nuclear site inspections.

We have prepared a super‐hydrophobic/super‐oleophilic modified sponge material (C‐PDMS‐PU) by attaching carbon powder and polydimethylsiloxane (PDMS) to a sponge skeleton by a simple dip‐coating method using a low‐cost polyurethane sponge as the raw material. The material has a C‐PDMS composite hydrophobic coating, which can efficiently and selectively absorb oil slicks on the water surface or organic solvents underwater that are 21–26 times its weight. Relying on this adsorbent, we have built an oil collection device that can in‐situ absorb/desorb oil with a dynamic viscosity ranging from 0 CP to 172 CP on the water surface or underwater. This oil collection device is small, simple to operate, and portable, thus freeing the adsorbent from the limits of adsorption capacity while continuously and efficiently recovering the oil from the sea surface, hence achieving the integration of adsorption and separation. This new adsorbent and the oil collection device have promising applications in emergencies, such as organic solvent spills, tanker spills, and oil spills from offshore rigs. [ABSTRACT FROM AUTHOR]

In this study, a novel sodium alginate–streptomycin sulfate composite aerogel (Alg–Stre) was synthesized by using chemical grafting and vacuum freeze-drying techniques to remove heavy metal ions from water. The experimental results show that the prepared Alg–Stre can effectively remove heavy metal ions such as Pb2+ and Cu2+ from water. Among these ions, Alg–Stre demonstrated the best removal effects for Pb2+ (99.8%, 0.1 mM) and Cu2+ (94.6%, 0.1 mM) in water. The utmost adsorption capacities of Alg–Stre for Pb2+ and Cu2+ are 280 mg g−1 and 160.2 mg g−1, respectively, which are competitive with those of most reported Pb2+- or Cu2+-sorbents. In addition, the adsorption abilities of Alg–Stre for Pb2+ and Cu2+ remained stable in solution pH values of 3.0 to 6.0 and at ambient temperatures of 20 °C to 50 °C. The simple preparation process, high removal efficiency, suitability for different environments and conditions, and recyclability of Alg–Stre confirm the broad application prospects of this material in the field of sewage disposal. [ABSTRACT FROM AUTHOR]

Poly(m-phenylenediamine) has a wide range of applications in adsorption due to its high amino content; however, its nanoparticles tend to aggregate in water and are not easily separated from aqueous solutions. In this research, a soft and easily separable adsorbent material was successfully prepared by cross-linking poly(m-phenylenediamine) and chitosan through hydrogen bonding. Experimental results showed that the prepared chitosan and poly(m-phenylenediamine) hybrid membrane (CS/PmPD) could selectively reduce Au(III) from a mixture of multiple metal ions (Cu2+, Zn2+, Ni2+, Cd2+, and Au(III)). The maximum treatment capacity of Au(III) reached 410 mg g−1 under optimal adsorption conditions (pH = 3.0 and adsorption time of 120 min). The CS/PmPD membrane can be regnerated after rinsing with sodium bisulfite solution, and its performance remains stable after multiple cycles. In addition, the membrane has achieved satisfactory results in treating the actual CPU gold-containing leachate. Therefore, the CS/PmPD membrane has a promising application in gold recovery from electronic wastes. [ABSTRACT FROM AUTHOR]

To quickly and efficiently recover precious metal gold from electronic waste products, we synthesized a novel hollow polym‐phenylenediamine (PmPD) nanosphere using the sacrificial template method and applied this materials to reduce and recover Au(III) in an aqueous solution. Experimental results show that the as‐prepared hollow PmPD has high selectivity and treatment capacity for Au(III), and can selectively reduce Au(III) from mixture metals solutions, including Cu2+, Zn2+, Ni2+, Cd2+, and Au(III) mixed solutions. Under room temperature and solution pH 4.0, the maximum treatment capacity of hollow PmPD for Au(III) reaches 1185.18 mg/g in 10 min of equilibrium time. The reduction ability of hollow PmPD remains stable in a pH range of 1.0 to 10.0 and under an ambient temperature ranging from 0 °C to 50 °C. Hollow PmPD can be regenerated via simple NaHSO3 solution washing, and its performance remains stable after repeated recycling. The satisfactory results obtained in treating the computer CPU leaching solution suggest that the hollow PmPD has broad application prospects in recovering gold from e‐waste. [ABSTRACT FROM AUTHOR]