[en] Trilayer films in which a superconducting YBa₂Cu₄O₈ (YBCO) layer is sandwiched between two ferromagnetic La_0.67Ca_0.33MnO₃ (LCMO) layers are formed by facing-target sputtering technique. The difference of superconducting transition temperature (T_c,on) between YBCO single layer and LCMO/YBCO/LCMO trilayers as functions of YBCO thickness is described by the magnetic proximity effect in superconductor/ferromagnet structure

[en] Transport properties of La_0.67Ca_0.33MnO₃ (LCMO)/YBa₂Cu₄O₈ (YBCO)/LCMO sandwiches were studied. An oscillatory resistance occurs with a period 30 nm in the series of LCMO (50 nm)/YBCO/LCMO (50 nm) films when the thickness of the YBCO layer is less than 60 nm. In contrast to that for LCMO films, the metal-semiconductor transition temperature for LCMO/YBCO/LCMO films is enhanced and strongly depends on the thickness of the YBCO layer. The magnetoresistance ratio also shows a non-monotonic behavior and a long oscillatory period (80 nm) is found for LCMO (100 nm)/YBCO/LCMO (100 nm) films. These results imply that the magnetic spin interaction between the two LCMO layers may exist through the normal-conductive YBCO layer

[en] Based on dual-energy X-ray technologies and forward scattering, brand new explosive detection method is presented. Dual-energy technologies can obtain the information of the effective atomic number (Z_eff) of an irradiated component, while the intensity of the forward scattered photons can reveal the information of the density according to our research. Therefore, the existence of the explosive can be effectively identified by combining these two characteristic quantities. Compared with the earlier inspection approaches, the new one has a series of particular advantages

[en] Highlights: • The accuracy of characterizing the contrast of an isolated 25 attosecond pulse is highly dependent on the energy resolution of the electron energy spectrometer. • Magnetic-bottle electron energy spectrometer has insufficient resolution for accurate contrast measurement. • New design in the magnetic-bottle spectrometer improved the resolution by restricting the acceptance angle with a small pinhole. • The satellite pulse of the isolated 25 attosecond can be characterized with less than 10 percent error by the new magnetic-bottle spectrometer design. - Abstract: We quantify the effects of the energy resolution of a magnetic bottle electron spectrometer in an attosecond streak camera on the accuracy of measuring the relative amplitudes of satellite pulses around the main attosecond pulse. Our numerical simulations show that the spectral resolution can be significantly improved by restricting the acceptance angle using a pinhole located near the source of the photoelectrons. The intensity of the pre- and post-pulses which are 1% and 10% of a main 25 as pulse can potentially be measured with less than 10% error by two practical time-of-flight spectrometer designs

[en] Based on coded aperture technology, a new method for forward scattering imaging is presented. The intensity of the forward scattered photons can reveal the information of the density. Combined with dual-energy technologies, which can obtain the information of the effective atomic number (Z_eff) of an irradiated object, contrabands such as explosives can be discovered. By using the MCNP code, an simulation is conducted, and the result is promising. (authors)

[en] A transistor current-stabilizing device was developed and constructed in 1983 with a set of motor-generator as its power supply. It is used for the excitation and stabilization of the analyzing magnet, replacing the previous current-stabilizing device made in USSR. This current source has high current stability, simple structure. It is easy to use, reliable for long-term operation, and energy-saving

[en] Based on dual-energy X-ray technology combined with forward-scattering, a brand new explosive detection method is presented. Dual-energy technology can give the information on the effective atomic number (Z_eff) of an irradiated component, while the intensity of the forward scattered photons can reveal the density information according to our research. Therefore, the existence of the explosive can be effectively identified by combining these two characteristic quantities. Compared with the earlier inspection approaches, the new one has a series of particular advantages, such as high detection rate, low false alarm rate, automatic alarm and so forth. The project is ongoing. (authors)

[en] Semiconductor photocathode and metal photocathode have different properties. To consider the properties of both, we studied a new type of photocathode - ion implanted photocathode. Cesium ions are implanted into a metal substrate. A photocathode preparation chamber is set up to make this photocathode. A cesium ion source is attached to the common photocathode preparation chamber. In the past two years, we finished making this photocathode and did research on its properties. A series of experiments have been done with different metal substrates, implanting dosages and implanting energies, in order to get a kind of photocathode material with high quantum efficiency and good stability. An increase of quantum efficiency after implantation has been observed. A more interesting result is that the emission spectrum becomes broader

[en] Biomass gasification using lattice oxygen (BGLO) of natural hematite coupling with steam was conducted in a fluidized bed reactor. The presence of hematite particles evidently facilitated to biomass gasification. Comparing with biomass steam gasification (BSG), carbon conversion and gas yield increased by 7.47% and 11.02%, respectively, and tar content lowered by 51.53%, in BGLO with an S/B of 0.85 at 800 °C. In this case, 62.30% of the lattice oxygen in the hematite particles was consumed in the biomass gasification. The reaction temperature, steam-to-biomass ratio (S/B) and reaction time on the performance of hematite particles were extensively investigated, in terms of gas distribution, heating value, yield and carbon conversion. With the reaction temperature increasing from 750 to 850 °C, the gas yield increased from1.12 to 1.53Nm³/kg, and carbon conversion increased from 77.21% to 95.49%. An optimal S/B ratio of 0.85 was obtained in order to maximize the carbon conversion and gas yield of BGLO. At this ratio, the gas yield reached 1.41Nm³/kg with carbon conversion of 92.98%. The gas concentration was gradually close to that of BSG at the end stage of BGLO due to the active lattice oxygen was depleted with the proceeding of reactions. - Highlights: • Biomass gasification using lattice oxygen (BGLO) was studied with hematite as oxygen carrier under steam atmosphere. • Lattice oxygen can improve evidently the gas yield and carbon conversion efficiency. • BGLO has major advantages of avoiding pure oxygen consumption and reducing tar. • Optimum operating conditions were 800 °C and steam-to-biomass ratio of 0.85

[en] Technical Standard for Security Engineering (GB 50348) is a mandatory national engineering construction standard jointly issued by Ministry of Housing and Urban-Rural Development and state administration formarket regulation, it has been important basis for conducting security engineering inspections in various industries. As a high-risk security engineering for special industries, the physical protection engineering of nuclear facilities has been the focus of supervision of the competent authorities of the industry in relation to its design, construction, operation and maintenance. In recent years, with the development of new security technologies, new requirements have been put forward for the inspection of physical protection projects. This paper introduces the experience and thinking of carrying out physical protection engineering inspection of nuclear facilities in accordance with the . (authors)