[en] The sump filter is an important and exclusive safety facility in nuclear power plants. Its function is to collect the leaked water and sprayed water in containment vessel under LOCA condition. The collected water can be used periodically to avoid the damage of injection pump and spray system with impurity. In this paper, the typical module is chosen as an example to be analyzed using finite element model with ANSYS software. The stresses are analyzed under different conditions. The influence of additional water is decided by experience formula and relevant test. In the seismic analysis, the influence of the fluid around the structure has been considered. Based on the RCC-M Code, the strengths of cartridge and shell structure of the sump filter are assessed. The results show that the new type of sump filter has perfect anti-seismic properties and can achieve the strength requirement. (author)

[en] As generation III of nuclear power unit, TaiShan EPR nuclear power plant has a good qualification practice and established a suitable qualification strategy to reduce some unnecessary qualification activity. The plant has also established complete qualification documentation. The concept of qualification preservation and qualification preservation sheet have been induced to keep the qualification statues ongoing. The rational quantity and category of qualification condition have been determined to guarantee the feasibility of equipment qualification. Equipment qualification under severe accident has been implemented for the first time, it will guarantee the available of equipment under severe accident condition. (authors)

[en] An expression for ponderomotive force caused by electromagnetic fields is derived from Valsov-Maxwell equations in a non-stationary, unmagnetized plasma. Comparison between this result and earlier ones is given. (Author)

[en] This paper focused on the fire-induced incident or accident in CPR1000 reactor building. It studied the different fire-induced incident or accident in each Safety Fire Zone of the building, and discussed the influences on the relevant safety mitigation systems under this situation. Finally, this paper provided some reasonable improvement suggestions to avoid such situation and improve the plant safety performance. (authors)

[en] Local operations under fire scenarios in nuclear power plant are usually taken to suppress the fire only or to bring reactor to safe shutdown stable status. The focus of this study is on the safe shutdown local operations. This study classified the local operations into different levels based on the safety importance. Based on this classification, the related operation requirements, the principles and measures of route design, the requirements of personnel protection are studied. This is an importance guideline to the new nuclear power plant construction and the new reactor type design in local operations under fire scenarios analysis of the actual operating characteristics in pressurized water reactor. (authors)

[en] In order to analyze the dynamic response of the reactor structure, a three-dimensional nonlinear was established. The model overcame many nonlinear factors such as clearance, contact, friction, damping, pretension, impact, fluid-structure coupling and connection stiffness. Considering the fluid-structure coupling between the core barrel and the RPV, the hydrodynamic mass matrix was modeled and verified by ANSYS acoustic element. Three-dimensional upper core plate, lower core support plate was set up. Multi-group fuel assembly was built, which considered the preload and bounce with the core plate, the clearance and impact with the core shroud. The model accurately simulated the dynamic response of the reactor structure because of the coupling of horizontal and vertical directions. Finally, the response of each component was obtained by inputting the time history of the impact acceleration in three directions, which provided the input for the stress analysis of the components and the impact experiment of the control rod drive line. The method in this paper can offer a reference for the three-dimensional nonlinear dynamic analysis of the reactor structure. (authors)

[en] If the fuel rods of nuclear reactor are damaged, the fission gases such as ¹³¹I will be released to the reactor building, increasing the risk of internal exposure to personnel. The analysis on CRP1000 unit showed that it can lead to the internal exposure risk to personal even if only one of the fuel rods is damaged. As the fuel damage increased to 0.25% of operation limitation, protective measures are required even if the purify system is turned on. The radioiodine hazard control and protection measures of ¹³¹I are discussed with reference to the practical nuclear power plant operation experience. (authors)

[en] In order to ensure the safety functions of nuclear power plants in case of internal flooding, it is necessary to consider protection against internal flooding in nuclear power plant design and evaluate the consequence to verify that the target of internal flooding protection can be achieved. According to the study on internal flooding protection purposes, requirements and protection measures, assumptions, methods and steps of internal flooding deterministic safety assessment were sought and presented. Based on a boric acid transportation room and reactor cavity and spent fuel pool cooling and treatment (PTR) pump room of 1000 MWe nuclear power plant, the method was applied and verified. The analysis result shows that the boric acid transportation room doesn't need any protections, but the PTR pump room needs to take drain measures in order to perform the nuclear safety functions. (authors)

[en] Low-cost synthesis of high-quality ZnS films on silicon wafers is of much importance to the ZnSbased heterojunction blue light-emitting device integrated with silicon. Thus, a series of ZnS films were chemically synthesized at low cost on Si(100) wafers at 353 K under a mixed acidic solution with a pH of 4 with zinc acetate and thioacetamide as precursors and with ethylenediamine and hydrochloric acid as the complexing agent and the pH value modifier, respectively. The effects of the ethylenediamine concentration on the crystallization, surface morphology, and optical properties of the ZnS films were investigated by using X-ray diffractometry, scanning electron microscopy, spectrophotometry, and fluorescence spectroscopy. A mechanism for the formation of ZnS film under an acidic condition was also proposed. All of the ZnS films were polycrystalline in nature, with a dominant cubic phase and a small amounts of hexagonal phases. The crystallization and the surface pattern of the films were clearly improved with increasing ethylenediamine concentration due to its enhanced complexing role. The absorption edge of the films almost underwent a blue shift with increasing ethylenediamine concentration, which was largely attributed to the quantum confinement effects caused by the small particle size of the polycrystalline ZnS films. Defect species and the corresponding strengths of the ZnS films were strongly affected by the ethylenediamine concentration.

[en] Seventeen years Sea Surface Current (SSC) data from multi-satellite altimeters were used to investigate the upper layer circulation structure over the South China Sea (SCS) . And combined with QuikScat Sea Surface Wind (SSW) data, the relationship between upper layer circulation over SCS and SSW were analyzed. The results show that the largest current velocity and the greatest change of the circulation over the SCS are in the area east of the Indochina Peninsula; There are two main modes of the SCS upper layer circulation, the winter mode from October to next February and the summer mode from June to August. SCS circulations in other months are in the transitional period of the two main modes; Through the correlation analysis of the SSW and SSC, a significant positive correlation, about 0.5, between current and wind was found at the boundary area of the SCS. However, there was a significant negative correlation, about −0.5, near the middle of the SCS. The results also show that the variation of the upper layer circulation structure over the SCS is significant seasonal, and it was mostly dominated by the monsoon