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[en] Highlights: • The photodetachment of H⁻ ion near two repulsive centers has been studied using the COT theory. • Our study suggests that the photodetachment cross section exhibits multi-periodic oscillatory structure. • Each peak in the Fourier transformed cross section corresponds to the scaled action of one detached electron's closed orbit. • Our study may guide the experimental researches in the photodetachment of multiply charged anions. - Abstract: Based on a theoretical model for the photodetachment of negative ion near a repulsive center, we study the photodetachment of H⁻ ion near two repulsive centers. Using the semiclassical closed orbit theory, we study the classical motion of the detached electron and calculate the photodetachment cross section of H⁻ ion near two repulsive centers. It is found that the repulsive centers have significant effects on the photodetachment of H⁻ ion. The photodetachment cross section of our system is strongly oscillatory compared to the photodetachment near one repulsive center. The calculation results suggest: if one repulsive center is kept fixed, with the decrease of the distance between two repulsive centers, the oscillating amplitude in the cross section becomes enlarged and the photodetachment cross section exhibits a multi-periodic oscillatory structure. In order to show the correspondence between the oscillation in the photodetachment cross section and the detached electron's classical closed orbits clearly, we make a Fourier transformation for the scaled photodetachment cross section of this system. Each peak in the Fourier transformed cross section corresponds to the scaled action of one closed orbit. We hope that our study will be useful in directing the future experimental research of the photodetachment processes of multiply charged anions

[en] A type of glow discharge triggered pseudospark switch is designed, and the relationship among the delay and jitter of the switch and the glow discharge current, gas pressure, trigger Jantage and anode Jantage is studied. When the glow discharge current is less than 0.30 mA, the switch can not be triggered; when the current increases from 0.35 mA to 0.6 mA, the delay and jitter decrease; when the current is about 0.60 mA, the delay and jitter are stable. When the He pressure is lower than 6 Pa, the switch can not be triggered, which is consistent with the theoretic value 6.95 Pa; when the He pressure is between 6 Pa and 12 Pa, the delay and jitter lessen as the gas pressure increases; the switch can work in a stable state when the gas pressure is more than 12 Pa and less than 30 Pa. When the gas pressure is 12 Pa, if the trigger Jantage is less than 3 kV, the switch is difficult to be triggered; the delay and jitter minish as the trigger Jantage increases, and achieve stable states when the trigger Jantage is more than 5.3 kV. When the He pressure is 12 Pa, the glow discharge current is up to 0.70 mA and the trigger Jantage equals 5.8 kV, the delay of the switch is approximately constant for anode Jantage from 8 kV to 25 kV. (authors)

[en] Thermal fatigue phenomenon is well known and feedbacked in the nuclear power industry. Targeted screening principles has been developed and applied. However, a thermal fatigue failure, “Swirl Penetration” of small-diameter pipeline, was identified through a Reactor Coolant System (RCS) leakage in a nuclear power plant. Unexpectedly, this failure is not within the scope of previous screening principles of thermal fatigue. It is characterized in that the high-temperature main piping is connected downward with a certain length of vertical small-diameter piping, and then the vertical piping turns horizontally through an elbow. The reactor coolant in the lower pipeline does not flow under normal operation conditions. Subject to long-term cyclic thermal fatigue, cracks initiate and propagate in the elbow. Through researches, corrective measures are put forward to prevent, mitigate or discover it. (paper)

[en] Based on the current situation of fault diagnosis of instrument control card, this project constructs the normal and fault reference models of instrument control card by simulation modeling, and proposes a model reference fault diagnosis method based on simulation test. On the basis of PSPICE, the simulation model of the power division card is established. The circuit schematic diagram is verified by Time Domain analysis method, and the validity of model reference method in card fault diagnosis is verified. The TP11 waveform of R29 circuit breaker is simulated by taking the simulation analysis waveform of a certain type of card as the sample, and the fault waveform case base is accumulated. This method lays a foundation for fault simulation diagnosis and data analysis of the card. (authors)

[en] In this work, the response characteristics of the microwave limiter under various high power microwave irradiation are investigated via both simulation and experiment, and the simulation results match those of the experiment well. When the input power exceeds 6 dBm, a spike leakage phenomenon is observed. As the input power increases, the rise time and pulse width of the leakage peak decrease, whereas the leakage power gradually increases. However, the leakage power of the plateau firstly linearly increases, then gradually decreases, and finally slightly increases. Moreover, the pulse width and repetition frequency have almost no influence on the characteristics of leakage pulse, and the leakage energy decreases as the injection power increases. (authors)

[en] In order to allocate NPP equipment management and maintenance resources reasonably, improve the reliability of equipment, ensure the NPP safe and stable economic operation, the classification management has to be carried out for the equipment of NPPs. This paper studied the reliability of equipment classification method based on AP913 equipment reliability management system, and eventually developed a new classification process which was different from the classical RCM and Streamlined RCM. Based on this method, the 205 systems of equipment classification work has been completed in a domestic nuclear power plant successfully. (authors)

[en] The results from investigation of large quantity of fault outcrops and artificial earthquakes suggest that the Lintong-Chang’an fault zone mainly consists of two faults. One is the Majie-Nianwan fault that separates a branch of Wangjiabian-Houjiawan fault on the right bank of the Bahe River; the other is the Hujiagou-Shoupazhang fault that separates a branch of Zhongdicun-Tangjiazhai fault in Tongrenyuan and Shaolingyuan. As tensional dip-slip normal faults, the faults distribute with approximately parallel equal intervals in local regions and the profiles drop in a step-like form to the northwest, presenting a Y-shape combination. The result from deep seismic reflection indicates that the fault is about 5∼8 km in depth, which is not only a basement fault, but also a listric normal fault in the deep stratum. The Lintong-Chang’an fault is a typical outstretching rift system under the NS-trending tension stress field. At the same time, affected by the sinistral strike slip of the Yuxia-Tieluzi fault, the fault extends like a broom from the northeast to the southwest.

[en] Seismic design spectra are very important for defining earthquake action and evaluating the safety of nuclear power plants (NPPs). This paper performs comparative analysis on the spectra of NPP seismic design code in China and the R.G. 1.60 spectra in USA, in light of the statistic in strong ground motion recordings which are used to develop design spectra and the statistical methods. The result is useful to deep understand the key factors which should be taken into consideration during the determination of seismic design spectra, and could be a reference for the seismic design of NPP and relevant nuclear safety review. (authors)

[en] A layer-wound mylar dielectric parallel-plates Blumlein line has been developed, which adopts S-type layer winding and is 50 cm × 18 cm × 12 cm in size. Its characteristics of high voltage insulation and output pulse were studied. The results simulated using equivalent circuit by PSpice software, consist with the results of experiment. It is found that the increase in switch inductance reduces the rise time of output pulses and distorts the output pulse shape, introducing reflections as well. The parasitic impedance causes some power loss in the line as the output pulse amplitude is lower than expected. The Blumlein line can deliver a maximum output of 50 kV to a matched load with duration of 180 ns and rise time better than 50 ns. (authors)