[en] It was found in this work that photosensitive monomers, bisphenol A dicinnamate ester and hexafluorobiphenol a dicinnamate ester were crosslinked under irradiation of linearly polarized ultraviolet light. The exposed films induced homogeneous and homeotropic alignment of liquid crystals (LC), respectively. We verified through experiments that it was fluorinated groups that caused the generation of LC homeotropic alignment on the crosslinked film. Photoreaction process was revealed by Fourier transform infrared spectra. There was no clear morphological anisotropy on these aligned films observed through atomic force microscope analysis. The surface energies were measured and homeotropic alignment reason was discussed in this work

[en] Through the analyses the neutron noise character of the sub-critical reactor, a micro-current amplifier was designed that can be used to authentication neutron fluctuations characteristics of the sub-critical experiment facility 'Venus No.1' of Accelerator Driven System. At last, 10^-9-10^-11 A micro-current can be pass band amplified and conversion to voltage signal. (authors)

[en] Highlights: • Five among six Rh_2TMSn Heusler compounds show structural instability. • The instability can be explained by the band Jahn–Teller effect. • The compounds can be categorized into two groups according to their DOS at E_F. • Rh_2MnSn has the largest tetragonal distortions with c/a = 1.9. - Abstract: Electronic structures of Rh_2TMSn (TM = Cr, Mn, Fe, Co, Ni and Cu) full Heusler compounds are calculated by the state-of-the-art electronic structure codes with the local density approximation aiming to understand the structure instability microscopically. The instability of the compounds can be explained by the band Jahn–Teller effect. The compounds can be categorized into two groups: In the first group, the density of states at the Fermi level are contributed mainly from Rh, while in the rest, both the Rh and TM atoms contribute. The high density of states at the Fermi level of the first group compounds may be smoothed and the highly symmetric phase is stable as found in experiments. The compounds in the second group tetragonally distort according to our calculation and was found in the experiments

[en] Highlights: • Molten salt thermocline storage with packed phase change bed is simulated. • Phase change material can remarkably increase the effective discharging energy. • Thermocline can be divided into three stages including phase change layer. • Melting point of phase change material should be slightly below initial temperature. • The discharging efficiency increases with the phase change material content. - Abstract: Comprehensive transient and two-dimensional numerical model is developed to study energy storage performance of molten salt thermocline thermal storage system with packed phase change bed in solar thermal power. The results show that the packed phase change bed can remarkably increase the effective discharging energy and discharging efficiency. Because of phase change material, the thermocline can be divided into three stages including the high temperature thermocline, low temperature thermocline and phase change layer. As the melting point within the inlet and initial temperature increases, the whole discharging time decreases, while the effective discharging energy remarkably increases, and thus the melting point of phase change material should be within the initial temperature and effective outlet temperature for good heat storage performance. As the phase change material content increases, the effective discharging energy increases with the effective discharging time rising, and the effective discharging efficiency also increases

[en] The experiences of radiation survey and administration in the prophase on reconstructed radioactive work-site are summarized. The advance works are to investigate the reconstructed work-site, settle working plans, devise inspecting flow charts, deal with something in time in the local and train the staffers. The works about prophasic decontaminating, removing and cleaning up the site have been finished, which have established the deep foundation to develop later task. (authors)

[en] A new method based on random walk theory to model multiple elastic scattering of electrons is presented which gives the efficient convergence of scattering series. This method modelled the multiple scattering as a series of random walks on a unit sphere, with each scattering event equivalent to one step in the random walk sequence. The step size of the random walk is characterised by the scattering angle which is determined by the scattering differential cross-section. Dirac partial wave program ELSEPA has been used to calculate the differential cross-sections of electrons and positrons by neutral atoms. The position distribution of a point on this unit sphere after “n” steps of random walk yields the angular distribution of multiple scattering. The main advantage of this method is the faster convergence of the scattering series for small step size, which is the most computationally demanding scenario in Monte Carlo multiple scattering simulations in the radiation transport code. Equivalence to Goudsmit–Saunderson’s theory of multiple scattering is also demonstrated and the angular distributions obtained from both the random walk method and Goudsmit–Saunderson’s theory are compared. The convergence of the scattering series is checked by comparing the Legendre polynomial expansion coefficients obtained through the random walk method and Goudsmit–Saunderson’s theory. Comparisons showed that the scattering series converges very fast for smaller path lengths (< 50 × mean free paths)

[en] Highlights: • A simplified method for evaluating thermal performance of UTC is developed. • Experiments, numerical simulations, dimensional analysis and data fitting are used. • The correlation of absorber plate temperature for UTC is established. • The empirical correlation of heat exchange effectiveness for UTC is proposed. - Abstract: Due to the advantages of low investment and high energy efficiency, unglazed transpired solar collectors (UTC) have been widely used for heating in buildings. However, it is difficult for designers to quickly evaluate the thermal performance of UTC based on the conventional methods such as experiments and numerical simulations. Therefore, a simple and fast method to determine the thermal performance of UTC is indispensable. The objective of this work is to provide a simplified calculation method to easily evaluate the thermal performance of UTC under steady state. Different parameters are considered in the simplified method, including pitch, perforation diameter, solar radiation, solar absorptivity, approach velocity, ambient air temperature, absorber plate temperature, and so on. Based on existing design parameters and operating conditions, correlations for the absorber plate temperature and the heat exchange effectiveness are developed using dimensional analysis and data fitting, respectively. Results show that the proposed simplified method has a high accuracy and can be employed to evaluate the collector efficiency, the heat exchange effectiveness and the air temperature rise. The proposed method in this paper is beneficial to directly determine design parameters and operating status for UTC.

[en] The η meson photoproduction off deuteron γ d→η X are calculated, where assuming the η photoproduction from nucleon is dominated by the N₁₁(1535), and the η-nucleon-nucleon vertex matrix element Γ_dpn is approximated using the non-relativistic deuteron wave function. The cross section and differential cross section can fit the new data well, and the coupling constant of γnN is obtained

[en] SAC-PREARS is a special code for analyzing the steady state and transient safety characteristics of the passive residual-heat-removed system (PRHRS). SAC-PREARS is used for analyzing the steady state and transient thermal-hydraulic characteristics of the PRHRS of NHR-200 (Nuclear Heating Reactor). Some conclusions with important project meaning have been drawn

[en] Directional dose equivalent H'(d) of three kinds of β radioactive sources, ³²P etc. is detected by using β dose ratemeter No. FJ358A. The curve between directional dose equivalent rate and distance from direction face of three kinds of β radioactive sources is given; and shielding performance of 12 kinds of object, work-suit, rubber gloves, protective glasses and so on, against three kinds of β radioactive source is given. Some pieces of advice about how to deduce individual dose equivalent superficial are given. (authors)