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To investigate the radioactivity levels of seawater, sediments, and biota in the Daya Bay sea area, China, in order to establish the radioactivity baseline values, and provide basic data for the assessment of potential radiological risks that might result from the application of nuclear technology or human activities.

A high-performance photonic spin Hall effect is demonstrated in an anisotropic epsilon-near-zero (ENZ) metamaterial based on the wave-vector-varying Pancharatnam–Berry phase. The giant out-of-plane anisotropy of ENZ metamaterial induces strong spin–orbit coupling. With a small incident angle, photons with opposite spins move along opposite transverse directions gradually. After transmitting through a submicrometer thick ENZ metamaterial, the spin photons are fully separated with a spin separation of 2.7 times beam waist and transmittance of 70.1%, allowing a figure of merit F up to 1.9. A practical ENZ metamaterial consisting of an Ag nanorod array is proposed, whose figure of merit is still up to 0.006. This high-performance photonic spin Hall effect provides an integrated and practical way for the development of spin-photonic devices.

The broad applications of implantable glucose biofuel cells (GBFCs) have become very attractive in biomedical sciences. The key challenge of GBFCs is eliminating the inevitable product H2O2generated from the oxidation of glucose when glucose oxidase (GOx) is used as a catalyst while improving the performance of GBFCs. In this work, the cascade electrocatalyst, RBCs@NPDA was obtained through the in situ polymerization of dopamine to form nanopolydopamine (NPDA) on the surface of red blood cells (RBCs). The RBCs@NPDA can catalyze both fuels of H2O2and O2, so as to generate a high cathodic current (0.414 mA cm–2). Furthermore, when RBCs@NPDA was used as a cathodic catalyst in the membraneless GBFC, it exhibited the cascade catalytic activity in the reduction of O2–H2O2and minimized the damage to RBCs caused by the high concentration of H2O2. The mechanism research indicates that RBCs@NPDA integrates the property of NPDA and RBCs. Specifically, NPDA plays a catalase-like role in catalyzing the decomposition of H2O2, while RBCs play a laccase-like role in electrocatalyzing the O2reduction reaction. This work offers the cascade catalyst for improving the performance of implantable GBFC and presents a strategy for constructing catalysts using living cells and nanomaterials to replace deformable and unstable enzymes in other biofuel cells.

Microtextures were successfully fabricated on the rake face of the cemented carbide (WC/TiC/Co) tools through inductively coupled plasma etching technology. Two types of microtextured tools were designed and fabricated. Their performance in cutting the AISI 1045 medium carbon steel was tested and compared to that of conventional non-textured tools. The comparison involved cutting forces, cutting temperature, friction coefficient, tool wear, chip adhesion, and machined workpiece surface roughness. The results show that microtextures on the rake face of the cutting tool can make the cutting process more stable than a conventional non-textured tool, and different textures may be suitable for different ranges of the cutting speed. In the latter range 100–200 m/min, microtextures significantly reduce the cutting force, cutting temperature, friction coefficient at the tool–chip interface, while the anti-adhesion property of textured tools and the surface quality of machined workpieces attain their maximal values. The effectiveness of textures is shown to be affected by chip adhesion and blockage resulting from derivative cutting, which appears at high cutting speeds. Moreover, the violation of the structural integrity of textures and their damage can strongly deteriorate the cutting process at low cutting speeds.

A new dry cutting tool named WS2soft coated Micro-Nano textured self-lubricating dry cutting tool (WTT tool) is developed and tested. Dry turning tests have been carried out on 45# quenched and tempered steel with a WTT tool and three other types of alternative tools. The machining performance was assessed in terms of the cutting forces, cutting temperature, friction coefficient at the tool-chip interface, chip deformation, tool wear, and the surface roughness of the machined workpiece. The results show that the WTT tool has the best cutting performance among all the tools tested under the same cutting conditions. Through theoretical analysis and experimental results, the mechanisms of the WTT tool in improving cutting performance were put forward. Meanwhile, the effect of Micro-Nano texture and WS2soft coating on the cutting forces and the cutting temperature is analyzed. It can be concluded that the WTT tool can effectively improve the anti-adhesion and wear-resistance properties and increase the tool life.

•LES is carried out to investigate supersonic flow characteristics in five ducts with different cross-sections.•Ducts with complex cross-sectional geometries exhibit more abundant vortex structures and thicker boundary layers.•Rectangular-to-circular ducts lead to higher flow drag force and total pressure loss than square-to-circular ducts with the same inlet area.•“S”-shaped ducts show substantial flow separation and shock waves, withow separation and shock significant vertically-asymmetric characteristics.

Growing within: The reaction of added Ca2+ions with the CO2produced by respiration results in the endogenous production of a CaCO3scaffold in functionalized cells (see picture). These cells act as anticancer drug carriers with pH‐sensitive release, and can enhance the cytotoxicity of drugs by increasing the cellular uptake. The functionalized cells also have potential applications in heavy‐metal extraction.

Die endogene Erzeugungeines CaCO3‐Gerüsts in funktionalisierten Zellen ist das Resultat der Reaktion von zugesetzten Ca2+‐Ionen mit dem durch die Atmung erzeugten CO2(siehe Bild). Die Zellen können als pH‐empfindliche Tumortherapeutikaträger fungieren und die Zytotoxizität von Wirkstoffen durch deren verstärkte Aufnahme in Zellen erhöhen. Des Weiteren könnten sie zur Schwermetallextraktion geeignet sein.