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Requirements of the penetration test on various seamless gas cylinders are analyzed to determine the specific method of the penetration test on different types of gas cylinders. The actual penetration test on the cylinder for on-board storage of fuel for automotive vehicle is taken for example to make a comparison with the design method and validate correctness and reliability of the designed test methods; corresponding failure fracture is analyzed through a scanning electron microscope to validate the affect of the penetration test on safety performance of the seamless gas cylinder and predict the possible results under actual working conditions.

To explore micro-or nanoscintillator with a controllable architecture, a novel facile hydrothermal method easy for commercial run was used to synthesize pure and Ce doped β-NaLuF4 microcrystals at 453K. The morphology of uniform hexagonal prism with 3.3μm in diameter and 1.4 μm in thickness, respectively, is presented by the results of scanning electron microscopy (SEM). Powder X-ray diffraction (PXRD) patterns show the products are both pure hexagonal phase. Different from the undoped product without any irradiation, the Ce doped product has given strong broad band emission attributed to 5d4f transition of Ce3+, which can be potentially used as scintillator for biomedical imaging and detectors for high energy such as X-ray and γray. This synthetical strategy extends the understanding about nanomaterial chemistry and can be also useful for other systems such as fluorides, oxides and sulfides.

A whole machine tool structure is a muti-DOF system, it is usually composed of many parts which are connected with joint interfaces. The structure is complicated that the accuracy of modal test is always in a low level. When doing modal test, equivalent single DOF method can not only improve the efficiency and decrease the difficulty, but also exclude interferences such as random noise. In this paper, the author simplified a two-DOF system into an equivalent single DOF system and derived its frequency response function, then analyzed a testing device for fixed joint by using the equivalent single DOF method, and measured several groups of unit area dynamic characteristic parameters of fixed joint interfaces in different materials and different working conditions. The dynamic characteristic parameters can be used in further study of machine tool joint interfaces.

In this study, nano-crystallized TiO2 photoelectrodes prepared by doctor-blade method on ITO-PEN substrate applied on flexible tandem dye sensitized solar cells (DSSCs) have been investigated by field emission scanning electron microscopy (FE-SEM), UV-Vis spectrophotometer (UV-Vis), and I-V characteristics analyses. In the analysis of FE-SEM, TiO2 thin films prepared by doctor-blade method have the porous structure. The analyses of UV-Vis show that N3 and black dye could be adsorbed on the TiO2 thin films, and the absorption wavelength of TiO2 photoelectrodes could be obviously promoted from the ultraviolet ray to the visible light scope with N3 and Black dye adsorbed. It is great help for conversion efficiency of DSSCs. Under the irradiation of the sunlight simulator (AM 1.5,100 mW/cm2), the flexible dye-sensitized solar cell with double sensitized layers has the best conversion efficiency η =5.59 %.

This paper presents a low-power fast-settling low-dropout regulator (LDO) using a digitally assisted voltage accelerator. Using the selectable-voltage control technique and digitally assisted voltage accelerator significantly improves the transition response time within output voltage switched. The proposed LDO regulator uses the selectable-voltage control technique to provide two selectable-voltage outputs of 2.5 V and 1.8 V. Using the digitally assisted voltage accelerator when the output voltage is switched reduces the settling time. The simulation results show that the settling time of the proposed LDO regulator is significantly reduced from 4.2 ms to 15.5 μs. Moreover, the selectable-voltage control unit and the digitally assisted voltage accelerator of the proposed LDO regulator consume only 0.54 mW under a load current of 100 mA. Therefore, the proposed LDO regulator is suitable for low-power dynamic voltage and frequency-scaling applications.