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This paper presents a novel reaction microscope designed for ion–atom collision investigations, established at the Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China. Its time-of-flight (TOF) spectrometer employs an innovative flight-time focusing method consisting of two acceleration regions, providing optimal time focusing conditions for charged fragments with diverse initial velocities. The TOF spectrometer's axis intentionally tilts by 12° relative to the ion beam direction, preventing potential obstructions from the TOF grid electrodes. The introduced focusing method allows for a flexible time-focusing TOF spectrometer design without restricting the length ratio of the two regions. In addition, this configuration in our case significantly suppresses noise on the recoil ion detector produced by residual gas in the ion beam trajectory, which is a considerable challenge in longitudinal spectrometers. In a test experiment on the single electron capture reaction involving 62.5 keV/u He2+ ions and a helium atomic beam, the recoil longitudinal momentum resolution achieved 0.068 atomic units. This novel configuration and successful test run show excellent precision for ion–atom collision studies. [ABSTRACT FROM AUTHOR]

An optical fiber Mach–Zehnder interferometer based on double S-tapers is proposed for strain sensing. The double S-taper strain sensor is formed by two steps. The fiber is pulled during arc discharging, and a second arc discharge is performed while the fixtures are misaligned to form a S-taper. The transmission spectra were collected with different structural parameters, including the axial offset, taper region diameter, and transition region length. The transmission spectra of each group of parameters are compared and analyzed. This work is meaningful for further research on double S-taper strain sensors. When the axial offset is 60 μm, the S2-taper region diameter is 54 μm, the transition region length is 0.7 cm, the strain experiment is tested from 0 με to 800 με, and the strain sensitivity is 6.63 pm/με. In addition, the stability, reversibility, and temperature sensitivity were experimentally characterized. [ABSTRACT FROM AUTHOR]

Functional hollow nanomaterials are of great interest due to their unique physical–chemical properties. Oxynitride photocatalysts are a kind of promising material for solar energy conversion. However, nanoscale design of hollow oxynitrides was difficult to achieve due to the thermal instability of oxide precursors at high temperature. Here, single crystal zinc gallium oxynitride nanotubes were successfully synthesized via the Kirkendall effect with ZnO nanorods and Ga2O3 nanosheets as precursors, which can be attributed to the high diffusion rate of ZnO and the high melting point of oxynitride. Enhanced photocatalytic performance in CO2 reduction was achieved over the as-prepared ZnGaNO nanotubes, due to their higher specific surface area and less recombination of the photogenerated carriers. These results are expected to provide new guidance in the design and preparation of highly efficient nano-scaled oxynitride photocatalysts. [ABSTRACT FROM AUTHOR]

Single crystal ZnGaNO nanorods, exhibiting a high performance in CO2 reduction due to the high specific area and low defect density, were synthesized by a molten salt growth route. [ABSTRACT FROM AUTHOR]

Single crystal ZnGaNO nanorods, exhibiting a high performance in CO2 reduction due to the high specific area and low defect density, were synthesized by a molten salt growth route. [ABSTRACT FROM AUTHOR]

In the reconstruction of dielectric objects by integral equation approach (IEA), the forward scattering integral equation (FSIE) and the inverse scattering integral equation (ISIE) are alternatively solved in the frame of distorted Born iterative method (DBIM) or its variations. In this work, we consider the reconstruction under a limited observation which is more practical. We use a DBIM-like Gauss-Newton minimization approach (GNMA) incorporated with a multiplicative regularization method (MRM) and a line search method (LSM) to solve the ISIE and the inversion quality of scattering data can be enhanced. The numerical example for reconstructing a two-dimensional (2D) dielectric object is presented to illustrate the inversion approach. [ABSTRACT FROM AUTHOR]

Organic–inorganic composite photocatalyst g-C3N4–TaON with visible-light response was prepared by a milling-heat treatment method. The photocatalyst was characterized by X-ray diffraction, high-resolution transmission electron microscopy and UV-vis diffuse reflection spectroscopy. The activity of composite photocatalyst g-C3N4–TaON for photodegradation of rhodamine B is higher than that of either single-phase g-C3N4or TaON. The obviously increased performance of g-C3N4–TaON is ascribed mainly to enhancement of electron–hole separations both at the interface and in the semiconductors. [ABSTRACT FROM AUTHOR]

The species of Ancylis Hubner from China are reviewed. Twenty-eight species of the genus Ancylis are treated, including one new species, Ancylis ventriverticalis sp. nov. Ancylis amplimacula Falkovitsh, A. loktini Kuznetsov and A. obtusana (Haworth) are recorded for the first time from China and the female of Ancylis hemicatharta Meyrick is described for the first time. A distribution map and a key to the species of Ancylis from China are given. [ABSTRACT FROM AUTHOR]

Using X-ray diffraction (XRD), scanning electron microscope (SEM), and differential scanning calorimetry (DSC), we have investigated the reaction between MgB4 and Mg in its solid, liquid, and gas physical states. The XRD results indicate that the reaction of MgB4+Mg=2MgB2 always occurs independently of the different states of Mg. DSC measurements show that the solid–solid reaction MgB4( s)+Mg( s)=2MgB2( s), the Mg melting Mg( s)→Mg( l), and the Mg volatilization occur in turn with increasing temperature for mixed (MgB4+Mg) powder with a nominal stoichiometry of MgB2. SEM observations indicate that the resulting synthesized MgB2 samples, obtained from the MgB4+Mg mixtures, have a denser microstructure than those obtained directly from Mg+B mixtures. On the basis of XRD, DSC, and SEM results, a kinetic model for the reaction between MgB4 and Mg is proposed. [ABSTRACT FROM AUTHOR]

Using X-ray diffraction (XRD), scanning electron microscope (SEM), and differential scanning calorimetry (DSC), we have investigated the reaction between MgB4 and Mg in its solid, liquid, and gas physical states. The XRD results indicate that the reaction of MgB4+Mg=2MgB2 always occurs independently of the different states of Mg. DSC measurements show that the solid–solid reaction MgB4( s)+Mg( s)=2MgB2( s), the Mg melting Mg( s)→Mg( l), and the Mg volatilization occur in turn with increasing temperature for mixed (MgB4+Mg) powder with a nominal stoichiometry of MgB2. SEM observations indicate that the resulting synthesized MgB2 samples, obtained from the MgB4+Mg mixtures, have a denser microstructure than those obtained directly from Mg+B mixtures. On the basis of XRD, DSC, and SEM results, a kinetic model for the reaction between MgB4 and Mg is proposed. [ABSTRACT FROM AUTHOR]