[en] In this paper, calculation results from Fluid-Structure-Interaction Finite Element Method (FSI-FEM) and the theoretical solution are examined on the cylindrical liquid container case. The applicability of FSI-FEM is discussed. Results show that FSI-FEM is able to calculate the vibration characteristics and dynamic response of the liquid container accurately. This method can further be employed in predicting the dynamic characteristics and analyzing the seismic time history of complex FSI models. (authors)

[en] In order to undertake the construction project of the nuclear power plant in UK, Nuclear Safety Review and License Application for Nuclear Power Projects shall pass the GDA review conducted by UK ONR firstly. The GDA review is based on the SAP/TAG guidelines that issued by ONR, and related IAEA/WENRA guidelines and IEC standards. Through analyzing I and C design issues that are concerned by ONR and requirements of relevant guidelines and standards, based on the review experience of UK-EPR and UK-AP1000, the I and C overall architecture design strategies are proposed. It can be used as a reference for the follow-up GDA review project. (authors)

[en] The theoretical model and its application of CELL code are introduced. The code solves the integral transport equation in concentric circular geometry by collision probability method to obtain neutron spectrum and few group parameters. For a fuel rod cell and a burnable poison rod cell, the deviations of K obtained by WINS-D/4 and CELL are 0.024% and 0.23%, respectively. For the five zero power experiment cores, concerned with water reflector or beryllium reflector, the deviations of core K_eff measured value and calculated value with CELL and CITATION codes are less than 0.5%. For the first core of HFETR, the control rod positions calculated values of cold zero power and hot zero power are agreed with the measured values very well

[en] The progress of nuclear plant construction greatly intensify the market demand for indigenous digital instrument control system for nuclear power plants. However, it is hard to find the qualified suppliers who can provide numerous nuclear grade facilities for safety functions. We can only adopt non-nuclear grade facilities usually applicable to common industry standards from non-nuclear grade facilities suppliers, namely commercial grade items, which quality should be controlled and guaranteed as required by laws and regulations. With reference to current international experiences, we found that the Commercial Grade Dedication (CGD) has been proven to be a successful way. Basing on the designation and supplement of DCS for the generators No. 5 and No. 6 in Tianwan Nuclear Power Plant, we studied related national and international standard and CGD methods and found a set of CGD system and methods suitable for NPPs in China. They have been proven to be successful in Tianwan Nuclear Power Plant, and should be a valuable reference for CGD for nuclear field in China, or even in the world. (authors)

[en] Comparative analyses of a shield building subjected to a large commercial aircraft impact between decoupling method and coupling method are performed in this paper. The decoupling method is applying impact force time-history curves on impact area of the shield building to study impact damage effects on structure. The coupling method is using a model including aircraft and shield building to perform simulation of the entire impact process. Impact force time-history curves of the fuselage, wing and engine and their total impact force time-history curve are obtained by the entire aircraft normally impacting the rigid wall. Taking aircraft structure and impact progress into account some loading areas are determined to perform some comparative analyses between decoupling method and coupling method, the calculation results including displacement, plastic strain of concrete and stress of steel plate in impact area are given. If the loading area is determined unreasonably, it will be difficult to assess impact damage of impact area even though the accurate impact force of each part of aircraft obtained already. The coupling method presented at last in this paper can more reasonably evaluate the dynamic response of the shield building than the decoupling methods used in the current nuclear engineering design

[en] The method of inputting the seismic wave determines the accuracy of the simulation of soil-structure dynamic interaction. The wave method is a commonly used approach for seismic wave input, which converts the incident wave into equivalent loads on the cutoff boundaries. The wave method has high precision, but the implementation is complicated, especially for three-dimensional models. By deducing another form of equivalent input seismic loads in the finite element model, a new seismic wave input method is proposed. In the new method, by imposing the displacements of the free wave field on the nodes of the substructure composed of elements that contain artificial boundaries, the equivalent input seismic loads are obtained through dynamic analysis of the substructure. Subsequently, the equivalent input seismic loads are imposed on the artificial boundary nodes to complete the seismic wave input and perform seismic analysis of the soil-structure dynamic interaction model. Compared with the wave method, the new method is simplified by avoiding the complex processes of calculating the equivalent input seismic loads. The validity of the new method is verified by the dynamic analysis numerical examples of the homogeneous and layered half space under vertical and oblique incident seismic waves.

[en] In this study, we report a facile method to obtain air-stable n-type graphene by plasma-enhanced chemical vapor depositing Si₃N₄ film on the surface of graphene. We have demonstrated that the overlying Si₃N₄ film can not only act as the penetration-barrier against H₂O and O₂ adsorbed on the graphene surface, but also cause an effective n-type doping due to the amine groups at the interface of graphene/Si₃N₄. Furthermore, the studies reveal that the Dirac point of graphene can be modulated by the thickness of Si₃N₄ film, which is due to competing effects of Si₃N₄-induced doping (n-type) and penetrating H₂O (O₂)-induced doping (p-type). We expect this method to be used for obtaining stable n-type graphene field-effect transistors in air, which will be widely used in graphene electronic devices.

[en] A macro test of the group constant library TPLIB-95 was introduced. The TPLIB-95 is an updated group constant library created by China Nuclear Data Center for LWR fuel assembly calculation program package TPFAP based on the JENDL-3.1 evaluation nuclear data library. The calculations and analyses were carried out by using five thermal reactor benchmark issues, a set of PWR zero-power critical experiments, the first cycle reactor core of 300 MW Qinshan NPP as well as the first cycle reactor core of 900 MW Daya Bay NPP. The calculation results for the thermal reactor benchmark issues showed that the maximum deviation between the calculated and measured values for spectrum indexes is large, like 6.7% for ρ²⁸ of BAPL-2. However, the maximum deviation for k_eff is only 0.29% for TRX-2. The calculation results for zero-power critical experiments showed that the calculated value of k_eff obtained by using TPLIB-95 is closer to the measured value compared with the one obtained by using the original library TPLIB. The agreement between the calculated and measured values for critical boron concentration in the first cycle reactor cores in Qinshan NPP and Daya Bay NPP is quite good. The maximum deviation for the critical boron concentration is only 15 x 10^-6/L. (8 figs., 5 tabs.)

[en] We demonstrate a band-pass resonator in the terahertz (THz) range, based on a frequency-selective designer reflector. The resonator consists of a parallel-plate waveguide, a designed groove pattern cut into the output facet of each plate, and a reflecting mirror. The patterned facet supports a spoof surface plasmon mode, which modifies the reflectivity at the waveguide output facet by interacting with the waveguide mode. By tuning the geometrical parameters of the groove pattern, the reflectivity at the patterned output facet can be increased up to ∼100% for a selected frequency. Broadband THz waves are quasi-optically coupled into this resonator and reflected multiple times from the patterned facet. This leads to a narrowing of the spectrum at the selected frequency. The Q value of the resonator increases as the number of reflections on the patterned facet increases, reaching ∼25 when the THz wave has experienced 12 reflections. (paper)

[en] Hydrophilic iron oxide Fe₃O₄ nanoparticles (NPs) were prepared by a reverse micro-emulsion method. Functionalization of Fe₃O₄ NPs was then carried out via surface graft polymerization to achieve outstanding magnetic property. Characterization results indicate that grafted core–shell Fe₃O₄ displayed inverse spinel crystalline structure, while particle size and it’s distribution were controlled accordingly. The ferromagnetic behavior (60 A m² kg⁻¹) of grafted Fe₃O₄ NPs was restored close to bulk value through enhancement of Fe–O ionic bond.