The 14C content in 1961–1967 rings of each of three spruce pines grown at (68° N, 130° W), (47° 30' N, 129° 16' E) and (27° 13' N, 100° 20' E) were measured. Δ14C values of the three specimens rise dramatically from a common level (∼250‰) in 1961 to their respective maxima, 964‰, 909‰, and 743‰ in 1964 and then fall to a common level ∼680‰ in 1967. The observed Δ14C increase comes most likely from the nuclear bomb test of the USSR at 75° N in 1961, although there were many other tests since the 1950s. The different effects at different latitudes reflect the atmospheric circulation patterns in the stratosphere and the transport of 14C nuclei from the stratosphere to the troposphere.

Te-doped cadmium telluride (CdTe) films were deposited on ITO/glass substrates using the close spaced sublimation (CSS) method. The films were characterized by x-ray diffraction (XRD), the x-ray fixed-quantity (XRF) method, scanning electron microscopy (SEM) and the Hall effect. The XRD and SEM results show that appropriate Te doping would be favourable to the growth of CdTe crystallite. The Hall effect measurements indicate that the conductivity of CdTe films could be dramatically improved by Te doping. The work presented here suggests that p-type doping CdTe films can be produced using this deposition method.

High-performance dielectric materials, the critical candidate of multilayer ceramic capacitors, are urgently needed for advanced energy storage or pulse power technologies and applications. However, it is still challenging to simultaneously...

Polymer–inorganic hybrid Janus nanoparticles (PI‐JNPs) have attracted extensive attention due to their special structures and functions. However, achieving the synergistic enhancement of photochemical activity between polymer and inorganic moieties in PI‐JNPs remains challenging. Herein, the construction of a novel Janus Au–porphyrin polymersome (J‐AuPPS) heterostructure by a facile one‐step photocatalytic synthesis is reported. The near‐field enhancement (NFE) effect between porphyrin polymersome (PPS) and Au nanoparticles in J‐AuPPS is achieved to enhance its near‐infrared (NIR) light absorption and electric/thermal field intensity at their interface, which improves the energy transfer and energetic charge‐carrier generation. Therefore, J‐AuPPS shows a higher NIR‐activated photothermal conversion efficiency (48.4%) and generates more singlet oxygen compared with non‐Janus core–particle Au–PPS nanostructure (28.4%). As a result, J‐AuPPS exhibits excellent dual‐mode (photothermal/photodynamic) antibacterial and anti‐biofilm performance, thereby significantly enhancing the in vivo therapeutic effect in an implant‐associated‐infection rat model. This work is believed to motivate the rational design of advanced hybrid JNPs with desirable NFE effect and further extend their biological applications.

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The most promising candidates for energy storage capacitor application are relaxor ferroelectrics, among which, the perovskite structure ferroelectric ceramics have witnessed great development progress. However, less attention has been paid on tetragonal tungsten bronze structure (TTBS) ceramics because of their lower breakdown strength and polarization. Herein, a multiscale regulation strategy is proposed to tune the energy storage performances (ESP) of TTBS ceramics from grain, domain, and macroscopic scale. The enhanced relaxor behavior with dynamic polar nanodomains guarantees low remanent polarization, while the refined grains and enlarged bandgap ensure increased breakdown strength. Hence, excellent ESP is realized in unfilled TTBS Sr0.425La0.1□0.05Ba0.425Nb1.4Ta0.6O6 (SLBNT) ceramics with an ultrahigh recoverable energy density of 5.895 J cm−3 and a high efficiency of 85.37%. This achievement notably surpasses previous studies in TTBS ceramics and is comparable to that of perovskite components. Meanwhile, the energy density exhibits a wide temperature, frequency, and cycling fatigue stability. In addition, high power density (257.89 MW cm−3), especially the ultrafast discharge time (t0.9 = 16.4 ns) are achieved. The multiscale regulation strategy unlocks the energy storage potential of TTBS ceramics and thus highlights TTBS ceramics as promising candidates for energy storage, like perovskite structured ceramics.

Two-dimensional (2D) Bi$_2$O$_2$Se semiconductor with a narrow band gap and ultrahigh mobility has been regarded as an emerging candidate for optoelectronic devices, whereas the ambiguous phonon characteristics and optical properties...