Needle‐like ZnO nanowires with high density are grown uniformly and vertically over an entire Ga‐doped conductive ZnO film at 550 °C. The nanowires are grown preferentially in the c‐axis direction. The X‐ray diffraction (XRD) θ‐scan curve shows a full width at half maximum (FWHM) value of 2°. This indicates that the c‐axes of the nanorods are along the normal direction of the substrate surface. The investigation using high‐resolution transmission electron microscopy (HRTEM) confirmed that each nanowire is a single crystal. A room‐temperature photoluminescence (PL) spectrum of the wires consists of a strong and sharp UV emission band at 380 nm and a weak and broad green–yellow band. It reveals a low concentration of oxygen vacancies in the ZnO nanowires and their high optical quality. Field electron emission from the wires was also investigated. The turn‐on field for the ZnO nanowires was found to be about 18 V μm–1 at a current density of 0.01 μA cm–2. The emission current density from the ZnO nanowires reached 0.1 mA cm–2 at a bias field of 24 V μm–1.

We investigate the spontaneous pair production, including the Schwinger mechanism and the Hawking thermal radiation, of charged scalar particles from the near horizon region of a (near) extremal Reissner-Nordström black hole. The paradigm is equivalent to the dynamics of the charged scalar field in a specific AdS2 × S 2 spacetime with a constant electric field. Two possible boundary conditions are adopted to explicitly compute the corresponding production rate and absorption cross section. It is shown that the Schwinger production rate can be eventually suppressed by the increasing attractive gravitational force as the geometry changes from the extremal to the near extremal black hole. Consequently, the Schwinger mechanism and the Hawking radiation are generically indistinguishable for the near extremal black holes. The holographic description dual to the pair production is also briefly discussed.

A photoresponsive pea-like capsule (nanopea) that also represents a photothermal agent is constructed by wrapping multiple polymer micelles (polyvinyl alcohol, PVA) in reduced graphene oxide nanoshells through a double emulsion approach. Resulting nanopeas can transport multiple PVA micelles containing the fully concealed hydrophobic drug docetaxel (DTX) which can be later released by a near-infrared photoactuation trigger. Through integrating the rod-shaped adhesion and lactoferrin (Lf ) targeting, the nanopea enhances both uptake by cancer cellc in vitro and particle accumulation at tumor in vivo. A photopenetrative delivery of micelles/DTX to the tumor site is actuated by NIR irradiation which ruptures the nanopeas as well as releases nanosized micelles/DTX. This trigger also results in thermal damage to the tumor and increases the micelles/DTX permeability, facilitating drug penetration into the deep tumor far from blood vessels for thermal chemotherapy. This nanopea with the capability of imaging, enhanced tumor accumulation, NIR-triggered tumor penetration, and hyperthermia ablation for photothermal chemotherapy boosts tumor treatment and shows potential for use in other biological applications.

In this study, double-emulsion capsules (DECs) capable of concealing drug-incorporated targeted-supermolecules are developed to achieve "on-demand" supermolecule release and enhanced sequential targeting for magneto-chemotherapy. These water-in-oil-in-water DECs less than 200 nm in diameter are synthesized using a single component of PVA (polyvinyl alcohol) polymer and the magnetic nanoparticles, which are capable of encapsulating large quantities of targeted supermolecules composed of palitaxel-incorporated beta-cyclodextrin decorated by hyaluronic acid (HA, a CD44-targeting ligand) in the watery core. The release profiles (slow, sustained and burst release) of the targeted supermolecules can be directly controlled by regulating the high-frequency magnetic field (HFMF) and polymer conformation without sacrificing the targeting ability. Through an intravenous injection, the positive targeting of the supermolecules exhibited a 20-fold increase in tumor accumulation via the passive targeting and delivery of DECs followed by positive targeting of the supermolecules. Moreover, this dual-targeting drug-incorporated supermolecular delivery vehicle at the tumor site combined with magneto-thermal therapy suppressed the cancer growth more efficiently than treatment with either drug or supermolecule alone.

Hydrothermal experiments on an andesite have been carried out under the condition of 110 °C, autogeneous pressure, 0.05 M H2SO4 solution and renewal of acid solution every 6 hours. The experimental results indicate that the plagioclase and pyroxenes in the treated samples show micropits and microfractures. Small crystals readily suffered from alteration, as compared with large ones, and the susceptibility of the minerals to the acid solution is decreased in the order of plagioclase, augite, hypersthene and opaque minerals. Plagioclase, which is the most reactive mineral in the experiments, shows an increase of SiO2, but a decrease of Al2O3, CaO and Na2O as the experiments proceeded. The chemical change of the treated andesite, it indicates that the relative amounts of SiO2, TiO2, MgO, ΣFeO, MnO and K2O increase, while those of Al2O3, CaO, Na2O and P2O5 decrease with an increase of the experimental duration. The relative mobility of chemical elements listed in decreasing order is P, Ca, Al, Na, Si, K, Mg, Fe, Mn and Ti in terms of the K value. It is no wonder that Ca, Al and Na are more mobile than others because these elements are readily released into solution from the more reactive plagioclase, while Mg, Fe etc. still stay in the less reactive pyroxenes and opaque minerals.