is considered as a next generation lithiumion battery (LIB) cathode material worth studying on account of its outstanding features. However, it is held back by poor cycling performance originated from the structure instability and side reactions. Here, spinel LNMO is decorated homogeneously via a facile hydrolysis and adsorption of γ-methyl-propylene trimethoxysilane (KH570), followed by thermal treatment at 750 °C, to bring a SiO 2 modification shell at the surface of LNMO and realize the ion doping of Si. The sintering process also brings more Mn 3+ in LNMO. However, only a moderate increase of Mn 3+ in LNMO can enhance the conductivity of ions and electrons, benefiting the enhancement of rate performance. The 0.8%-SiO 2 @LNMO cathode exhibits a high reversible capacity of 129 mAh g −1 , retaining a great capacity retention of 88% after 800 cycles at 1 C and 89.7% after 1000 cycles at 3 C. Meanwhile, a superior rate capability (90 mAh g −1 at 5 C) is achieved by applying the galvanostatic charge/discharge test.

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This paper presents a method for moderate pulsed X rays produced by a series diode, which can be driven by high voltage pulse to generate intense large-area uniform sub-100-keV X rays. A two stage series diode was designed for Flash-II accelerator and experimentally investigated. A compact support system of floating converter/cathode was invented, the extra cathode is floating electrically and mechanically, by withdrawing three support pins several milliseconds before a diode electrical pulse. A double ring cathode was developed to improve the surface electric field and emission stability. The cathode radii and diode separation gap were optimized to enhance the uniformity of X rays and coincidence of the two diode voltages based on the simulation and theoretical calculation. The experimental results show that the two stage series diode can work stably under 700 kV and 300 kA, the average energy of X rays is 86 keV, and the dose is about 296 rad(Si) over 615 cm area with uniformity 2:1 at 5 cm from the last converter. Compared with the single diode, the average X rays' energy reduces from 132 keV to 88 keV, and the proportion of sub-100-keV photons increases from 39% to 69%.

A ZnO:Ga single crystal with an applicable size of φ40 × 1 mm was prepared using the hydro-thermal method. The crystal exhibits good crystallinity and scintillation properties with a 63.94-arcsec full-width at half-maximum (FWHM) in the X-ray rocking curve (XRC) spectrum, 8% luminous non-uniformity, emission at 389 nm in the X-ray excited luminescence spectrum, fast response and 5.5% BGO luminous intensity. Furthermore, an X-ray pinhole imaging system of nanosecond temporal resolution with a ZnO:Ga single-crystal image converter was established to diagnose the cathode electron emission spatial distribution of an intense current diode. Results for shutter times of 4 μs and 5 ns were obtained, which directly represent the cathode electron spatial distribution throughout the entire pulse duration and during a certain moment of the pulse, respectively. The results demonstrate that the large ZnO:Ga single crystal can diagnose the spatial distribution of cathode electron emission in an intense current diode with high temporal resolution and provide new solutions for high-temporal-resolution diagnosis of a pulse radiation field.