[en] The line intensities of 0010-0000 transition of the symmetric-top PH₃ molecule at several temperature were calculated by directly calculating the partition functions and regarding the rotationless transition dipole moment squared as a constant. The calculated values of the total internal partition sums (TIPS) are consistent with the data of HITRAN database with -0.075% at 296 K. The calculated line intensities data at 1000 K and 3000 K are also in excellent agreement with the data in HITRAN database, which provide a strong support for the calculations of partition function and line intensity at high temperature. Then we extended the calculation to higher temperature. The line intensities and simulated spectra of υ₃ band of the symmetric-top PH₃ molecule at 4000 and 5000 K were reported. The results are of significance for the studying of the molecular high-temperature spectrum including experimental measurements and theoretical calculation. (authors)

[en] In this work, the triple differential cross section for electron impact ionization of helium in the special geometry of coplanar high incident energies large energy loss and close to minimum momentum transfer are calculated by use of the BBK and modified BBK model after the shield effect of the residual electron is considered. Then, the influences of the effective shield of residual electron on the triple differential cross sections and the physical nature of these effects are discussed in detail. (authors)

[en] This paper mainly discusses the nonlinear effect induced by the quantum coherence of the ground state fine structure energy-levels in a cascade-type four-level system. Coupling field excites the optical transition from the excited state lower fine structure energy-level to both two ground state fine structure energy-levels, which leads to a new absorption peak. It is shown that the smaller population relaxation rate between two ground state fine structure energy-levels is, the more significant quantum coherence is. However, this quantum coherence can be weakened by increasing the Rabi frequency of coupling field. (authors)

[en] Zigzag graphene nanoribbons with edges modified by different chemical groups are investigated by first principles calculations. The chemical groups considered include hydrogen, hydroxyl, ketone, and combination of hydrogen and hydroxyl. Band structures. DOS and charge difference density have been calculated. The results show that, the effect of different groups could be essentially ascribed to different types of edge. The structures of sp² type have little influence on electron state of the inner atoms of GNRs whose metallicity still remains. However the structures of sp³ type generate a band gap which will decrease with the increase of ribbon's width. The shift from metallicity to semiconducting occurs in both structures of GNRs-H₂ and GNRs-H₂O, while the structure of GNRs-O remains its metallicity as its Fermi level increases into the conduction band. By using this method of edge hybridization, the GNRs' band structure is prone to be controlled. (authors)

[en] Real-time monitoring safety parameters are very important both in NPP operation surveillance and emergency management. Base on the analysis of regulations, emergency technical requirements and technical document of NPP obtained construction license before Jan 1st of 2009, the real-time Monitoring Safety Parameters of PWR NPPs in concerning range were sorted out. (authors)

[en] In our previous experiment on CR-39 detectors, we found out that bulk etch rate of irradiated area is different from unirradiated area. Therefore, the traditional etching model should be revised. In this case, our modification which based on the theoretical studies printing out and the AFM observation was put forward and new etch rate : V'=V_t/V_irr, was defined. Then, modified track-diameter kinetics was used to clarify AFM analysis. In this research, the key parameters for 100 MeV Silicon ion include V_t=4.12 μm/h, V_irr=2.55 μm/h, V'=1.62, θ=61.03°. And the bulk etch rate V_b=1.58 μm/h. So the etch rate can be calculated whose value in V=2.61>V’. (authors)

[en] ITER equatorial port cell outside bio-shield plug is a place for allowing free personnel access after shutdown which accommodates various sensitive equipment and pipes. To ensure the personnel safety in port cell after shutdown, the distribution of dose rate in port cell was studied. Based on VisualBUS (CAD-Based Multi-Functional 4D Neutronics Simulation System), dose rate calculations were completed in port cell after shutdown. The result showed that dose rates in port cell are still 2 orders of magnitude more than desired limit (10 μSv/h) after one day shutdown. The optimization of bio-shield was needed. (authors)

[en] The first approach to critical of the SLOWPOKE reactor is described together with many as yet unpublished photographs of the event. The development of the reactor and the overpower testing are discussed.

[en] The ZED-2 (Zero Energy Deuterium) reactor is an experimental low-power critical facility located at the Atomic Energy of Canada Limited Chalk River Laboratories in Ontario, Canada. The facility is used to perform physics experiments in support of the CANDU and Advanced CANDU Reactor (ACR) programs. The reactor core is a large cylindrical vessel in which reactor fuel rods are positioned vertically. A heavy water moderator is pumped into the vessel to make the reactor critical. The ZED-2 design is very versatile: it can accommodate mixed fuel types in a variable number of fuel rods each with or without CANDU-type or ACR-type channels; channel coolants can be light or heavy water, or air, and can vary from channel to channel; lattices can be square or hexagonal with continuously variable lattice pitch; and some CANDU-type channels can be heated. Many of the experiments performed involve uniform cores containing the same type of fuel and channel in each fuelled location. However, at times a smaller number of fuel rods and channels are placed in the centre of a larger region of reference fuel to form a critical core assembly. These are called substitution experiments. The purpose of this paper is to describe why substitution experiments are performed, detail how they have historically been conducted and analyzed to extract the desired data from the test fuel, and finally how they are performed and analyzed today using specialized software.

[en] It introduces a circuit design of beam homogeneity measurement for heavy ion beam in the monitoring needs, which convert multichannel weak current from 10 pA to 100 nA of the output of parallel plate avalanche counter (PPAC) for large area with sensitive two-dimensional position to voltage signal from -2 V to -20 mV by current-voltage-converter (IVC) circuit which composed of T-feedback resistor networks, combined with data acquisition and processing system realized the beam homogeneity measurement in heavy ion tumor therapy of the Institute of Modern Physics. Experiments have shown that the circuit with speed and high precision. This circuit can be used for read-out of the beam for the Multiwire Proportional Chamber, Faraday Cup and other weak current sources. (authors)