[en] The stability of the intermetallics Gd₃(Fe,T)₂₉ and the site preferences of the ternary 3d or 4d transition element T were investigated using a series of inter-atomic pair potentials. The calculated results show that either V, Ti, Cr, or Mo atoms can stabilize Gd₃(Fe,T)₂₉ with monoclinic symmetry. The order of site preference of these stabilizing elements T is 4i2, 4i1 and 4g, where 4i2 corresponds to the greatest energy decrease. The calculated lattice parameters were found to be in good agreement with experiment. It is surprising that simple pair potentials can describe these extremely anisotropic materials. The calculated results also show that the addition of Cu and Ag does not stabilize the Gd₃(Fe,T)₂₉ phase

[en] Nuclear safety is the top priority of the development of nuclear power. Also the nuclear emergency response is the fifth defense in depth architecture which is the most important foundation of nuclear safety. This study is aimed at building an efficient design of advanced emergency command system to support the emergency work, based on emergency command system construction of Sanmen nuclear power project. First analyze required technical facilities of emergency preparedness and response. Then design the basic framework of system, and make clear of the division of emergency information platform. Describe hardware and software design of information platform as coordination office for emergency organization, and construct an integrated display and centralized control system, to meet the emergency organization of the meeting, control and command. (author)

[en] Recent results on spectroscopy from Belle are reviewed. Belle searches for the charged Z_b states in ϒ(5S)→B^⁎B^(⁎)π^± decays and for the neutral Z_b partner in ϒ(5S)→π⁰π⁰ϒ(nS) decays. The properties of the X(3872) state are updated with Belle's full data sample, and its charged partner is probed in the ρ⁺J/ψ final state. Belle searches for the C–odd neutral partner of the X(3872) in the ηJ/ψ and γχ_c1 final states. The ψ₂ charmonium state is observed for the first time in the γχ_c1 final state. A scan of e⁺e⁻→ηJ/ψ via initial state radiation shows obvious ψ(4040) and ψ(4160) signals but no evidence for an exotic Y state. The partial widths of ψ(4040) and ψ(4160) decaying to ηJ/ψ are found to be of order 1 MeV

[en] In Lingao Phase 1 nuclear power plant, violent piping vibration was found during the function test of the pump, especially when the pump was run under small flow. The authors of this article measured the dynamic stress of the piping with strain gauges and gave a fatigue life assessment of the piping with ASME and BS codes. (authors)

[en] The collective dose of nuclear power plant workers mainly comes from the outage period of nuclear power plant. The corrosion activation products deposited in the pipelines and the radiation dose field formed are the main sources of occupational exposure of workers in the nuclear facilities, and the changes of their numerical value also reflect the operating state of the NPP unit. Therefore, it is of great significance to monitor the activity and dose rate contribution changes of radionuclides in key pipelines and points in real time, and which is useful to take necessary protective measures for subsequent maintenance work and reducing the collective dose as much as possible. At present, the nuclear power plant only adopts the dose rate of the maintenance area to implement the corresponding protective measures during the outage period. Some nuclear power plants have implemented the source items investigation during the outage period, and have analyzed the radionuclide activity and dose rate contribution ratio of key pipelines and points in detail. And this work provides a reliable data basis for subsequent source items decontamination and dose reduction. However, during the oxidation operation of the outage period, it is change continuously for the activities of radionuclides at some key points. But there is no relevant instrument to monitor the trend of changes in the radioactivity in the pipeline in real time, which is reserved data blank for the subsequent radiation protection optimization and NPP unit operation evaluation.

[en] Aiming at the problem of frequently changing running state, high fault probability and lack of operator support means for marine nuclear power plant (NPP), a fault diagnosis method based on characteristic event sequence was proposed. In the arithmetic, the characteristic event sequence was defined to identify fault characters, and a standard characteristic event sequence chart was built according to NPP record running data. When the system ran out of the way, a characteristic event sequence was constructed from current running state data, and the accident grades and rough positions were diagnosed by comparing current event sequence with standard characteristic event sequence. Validated by experiments, the arithmetic can fix accident grade and rough position, and it has lots of excellences comparing to the traditional data driving arithmetic, such as easily casting back,explicable, and therefore it is practically useful. (authors)

[en] Capacitance sensor is generally used to measure gaps. It introduced a scheme which applies several capacitance sensors to monitor the displacement of the BEPCII superconducting magnets. This scheme includes sensors application, displacement and angle calculation, system structure design and monitor software design. At last, it gives the result of the experiment which proved the feasibility and measurement accuracy of the scheme. (authors)

[en] A simplified two-dimensional (2-D) magneto-optical trap (MOT) for loading atoms into a 3-D MOT is realized. Instead of utilizing multiple wave plates and beam splitters to cover a large cooling region, we deploy cooling beams with elliptical cross-section profiles to achieve a comparable cooling volume. This simplification reduces the cost and difficulty of alignment. The 3-D MOT achieves a loading rate of 2 × 10⁸ atoms per second via this simplified 2-D MOT. Correlation between the loading rate and parameters of optical system is also determined. (authors)

[en] Pressurizer water level is an important monitoring parameter to marine pressurized water reactor for operator to estimate operation transient of the reactor. However, pressurizer often takes on problems of false water level, over-range measurement of water level and the loss of measuring. A method based on support vector regression was used to reconstruct the pressurizer water level according to the coupling relationship between pressurizer water level and other thermal-hydraulic parameters, such as the average temperature between reactor core inlet and outlet, pressure and temperature of pressurizer, coolant inventory of main loop system, and charge and drainage flow. Simulation analysis shows that the method can quickly, accurately and efficiently reconstruct the pressurizer water level signal under normal operating conditions. (authors)

[en] The decays of bottomonia including Y(1S), Y(2S) and Y(5S) at Belle experiment are reviewed. For the Y(1S) radiative decays, the upper limits of branching ratios to charge-parity-even charmonia χ_cJ and η_c, and charmonium-like states X(3872), X(3915) and Y(4140) are measured. Some analyses on Y(2S) are underway, such as Y(2S)→γη_b, Y(2S)→γA₀, χ_bJ→ double charmonium. Transitions of Y(5S) to Y(nS)π⁺π^- and Y(5S) decays to B mesons final states are also studied. The decays with B meson include BB-bar, BB-bar*+B*B-bar, B*B-bar*, BB-barπ, BB^*π+B*Bπ and B^*B-bar*π.