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Marine biofouling is a worldwide issue that has aroused great concern in scientific community. Herein, a micron-laminated Cu-Al2O3 composite coating was facilely obtained via plasma spraying of Cu/Al2O3 powders to achieve eco-friendly and long-lasting antifouling performance along with superior wear resistance. The microstructure, long-term antifouling performance, and wear behavior of the Cu-Al2O3 coatings as a function of Al2O3 content were systematically investigated. Results indicated that the Cu-Al2O3 coating exhibited controlled slow copper ions leach rate of approximately 5 times lower than that of the Cu coating, promoting eco-friendly and long-lasting antifouling protection. Additionally, the copper ions leach rate from the Cu-Al2O3 coatings decreased as the Al2O3 content increased, which was mainly related to the Cu amount involved in dissolution reaction. Long-term antifouling efficiencies against bacterial survival and algae settlement for the Cu-Al2O3 composite coatings with 32.1-66.2% Al2O3 were higher than 90%. Furthermore, the Cu-Al2O3 coatings exhibited superior wear resistance by the strengthening of Al2O3. Continuous tribolayer containing trapped Al2O3 particles formed on worn surface was responsible for the excellent wear resistance of Cu-Al2O3 coatings. The outstanding comprehensive performance of Cu-Al2O3 coating combining long-lasting and eco-friendly antifouling ability and remarkable wear resistance gives clear insight into its potential applications in marine antifouling field. [ABSTRACT FROM AUTHOR]

Gd2O2S:Pr3+, Ce3+ scintillation phosphors (GOS) were successfully synthesized via a homogeneous precipitation followed by solid-state reaction method with Gd2O3, Pr(NO3)3·6H2O, Ce(NO3)3·6H2O, HNO3, NH3·H2O, CO(NH2)2, Na2CO3, and sublimated sulfur (S) as the starting materials. Fourier transform infrared spectrometer (FT-IR), differential scanning calorimetry-thermogravimetry (DSC-TG), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and photoluminescence (PL) were used to characterize the obtained products. FT-IR and DSC-TG results reveal that the precursor is mostly composed of gadolinium and carbonate groups with some crystal water and can be transformed into Gd2O3 phase at 1000 °C for 2 h in air. XRD analysis shows that pure Gd2O2S phase can be synthesized with the molar ratio of Gd2O3:Na2CO3:S=1:5:20 when the reaction temperature is 1000 °C and the reaction time is 2 h. FE-SEM analysis shows that the morphology of the obtained Gd2O2S product has a block and irregular polyhedron structure with a significant increase in size of about 4 μm. PL spectrum analysis shows that the strongest green emission of Gd2O2S:0.20% Pr3+, 0.0025% Ce3+ scintillation phosphor is observed around 513 nm, which is attributed to the 3P0→3H4 transition of Pr3+ ions. The average lifetime τ is calculated to be 1.43 μs for Gd2O2S:0.20% Pr3+, 0.0025% Ce3+ scintillation phosphor. The above results meet the wavelength and lifetime requirements of GOS fluorescent screen used in medical radiotherapy linear accelerator. [ABSTRACT FROM AUTHOR]

SrO–Na2O–Nb2O5–SiO2 (SNNS) glass–ceramics with Ta2O5 dopants were prepared by a method of conventional melt-quenching and crystallization. The effects of different contents of Ta2O5 dopants on the microstructures, dielectric properties, energy storage densities and discharge properties of SNNS glass–ceramics were exhaustively investigated. Results showed that the doping of Ta5+ cations can significantly improve the dielectric constant of SNNS glass–ceramics, attributing to the increase in NaNbO3 precipitation. In addition, an optimal amount of Ta2O5 doping can effectively reduce the grain agglomeration of the glass–ceramics and improve their electric breakdown strength. A maximum theoretical energy storage density reached 15.22 J cm–3 over SNNS glass–ceramics with 2 mol% of Ta2O5 dopants; in particular, approximately 0.41% of ultra-low dielectric loss was obtained in this composition. Besides, a tremendous instantaneous power density of 125 MW cm–3 was achieved at 400 kV cm–1 electric field in the single-layer capacitor based on those SNNS glass–ceramics, as well as a rapid discharge time of 10 ns. All these outcomes demonstrate the doped SNNS glass–ceramics have a giant potential for pulse power applications. [ABSTRACT FROM AUTHOR]

Transplantation of in vitro‐manipulated cells is widely used in hematology. While transplantation is well recognized to impose severe stress on transplanted cells, the nature of transplant‐induced stress remains elusive. Here, we propose that the lack of amino acids in serum is the major cause of transplant‐induced stress. Mechanistically, amino acid deficiency decreases protein synthesis and nutrient consummation. However, in cells with overactive AKT and ERK, mTORC1 is not inhibited and protein synthesis remains relatively high. This impaired signaling causes nutrient depletion, cell cycle block, and eventually autophagy and cell death, which can be inhibited by cycloheximide or mTORC1 inhibitors. Thus, mTORC1‐mediated amino acid signaling is critical in cell fate determination under transplant‐induced stress, and protein synthesis inhibition can improve transplantation efficiency. [ABSTRACT FROM AUTHOR]