[en] China Institute of Atomic Energy is developing a mobile vehicle inspection system. The system has the advantages of high energy and low irradiation dose, which uses the electron induction accelerator as the source of the radiation. When a ray beam is emitted, the accelerator can produce X ray with 2 ∼ 7.5 MeV energy, it is the ray device for class. Therefore, equipment commissioning site needs to have security chain measures to ensure personnel safety. Aiming at the characteristics of the commissioning site of high-energy and low-dose vehicle inspection system, this paper designs a set of safety interlocking system with PLC (programmable logic controller) as the main control unit and including door linkage, dose linkage and patrol linkage, describes the logic flow design of the safety interlocking system, the hardware implementation of the site and the PLC program design using the sequential control design method. (authors)

[en] A energy compensation detector for online pulsed gamma dose measurement is designed and developed. In this paper, the energy response function of the Si-PIN detector is simulated by MC method, and the results are compared with the experiments. It is showed that the doses measured by the energy compensation detector are well accorded with those by the TDL with the uncertainty ±5%. This energy compensation detector offers a new approach for online measurement of single pulsed gamma radiation dose. (authors)

[en] Background: A data acquisition system for online pulsed gamma dose measurement device is designed and developed, and its performance is tested. Purpose: The data acquisition system output electric charges and input energies have a good linear relationship in both the continued and pulsed input. Methods: Experiments have been done respectively on the TDL and 'Chen Guang' accelerator. Results: The results show that the relative deviations are less than 5%. Conclusion: This data acquisition system is a new approach for online measurement of single pulsed gamma radiation dose. (authors)

[en] Background: Normal green channel vehicle inspection methods have many flaws, such as low efficiency and long time expense. The accuracy depends on the experience of inspector and it can not meet the online inspection. Purpose: The aim is to develop a new method which can help the inspector to promote the vehicle inspection speed and accuracy. Methods: Using real time image processing and control system, a new imaging system was developed. Results: The actual test shows that the inspection time can be reduced to less than one minute and the inspectors can also be reduced to one or two persons. Also the inspection accuracy is greatly improved. Conclusion: The imaging system achieves good effect through actual tests. (authors)

[en] PNFN is a method for uranium exploration. Pulsed neutron source was used, prompt fission neutron and delayed fission neutron in the range of epithermal neutron energy were detected by using He-3 neutron detector. The PNFN responses under the condition of different uranium content, porosity were simulated by using the Monte Carlo method. The relationship between fission neutron and formation condition was studied. The obtained result show that the larger the formation porosity, the more little the calculated uranium content. The precision of uranium content can be increased by the correct of formation scattering cross-section obtained by prompt fission neutron die-away time spectrum. (authors)

[en] Based on the computer image processing technique, the waveform digitalization system for analogue oscillograph film has been developed. The system can accurately extract and recognize the waveform curve from complicated background, and the coordinate data of waveform can be saved. In this paper, the hardware structure and principle, software module, image processing pivotal arithmetic and technique are introduced in detail. The typical waveform films have been recognized and digitalized, the results indicate that the waveform digitalization system has the excellent character of high recognized precision, speed and automatization. (authors)

[en] The manufacture technology of GaAs semi-insulator detectors are introduced in details. The leakage current, time response, γ-ray response and proton sensitivity are measured. The simultaneous input-output measurement system in continuous proton pulse experiments are also introduced and the results of the measurement are analyzed as well

[en] Both bilayer and multilayer samples are bombarded at room temperature with Xe⁺(300 keV) or Ar⁺(90-120 keV) for the doses of 1 x 10¹⁵-1 x 10¹⁷ cm^-2. AES, XPS and RBS are used for the depth profiling of compositions. TEM observations are also carried out on multilayer samples. It is found that ion beam mixing occurs in cascade regime Q ∝ Φ^1/2 for the multilayers and effective Dt ∝ Φ^1/2 for the bilayers, respectively. Nonuniform mixing is observed in multilayers, particularly with Xe⁺ bombardment, which is consistent with the calculations of the deposited energy density distribution. Metastable β-Ti-Mo solid solution of bcc structure is formed after mixing. Impurities such as C, O significantly suppress the mixing and are also redistributed during ion bombardment

[en] In order to calibrate the sensitivity of the scintillating-film neutron detector with the scintillator thickness great than 0.1 mm in 5SDH-2 accelerator at the Radiation Metrology Center of China Institute of Atomic Energy, a neutron shield was designed by modeling and optimizing with MCNP program. Experiment results show that this shield can attenuate the neutron fluence out of collimator to one-tenth of that in the collimator, and constrain the background signal to the level of photomultiplier's (PMT) dark current, therefore, it can make signal-to-noise of the detector great than 1:1 for the detector with thickness of scintllator above 0.1 mm. Calculation results indicate that sensitivity change resulted from collimator scattering is less than 5%. (authors)

[en] The experiment study of the sensitivity to gamma rays is very important for a physics performance of ST-401 scintillating-film detector. In this paper, the basic principle and structure design of the scintillating-film detector is introduced, and calibration sensitivity experiments have been carried out at Cobalt-60 standard radiation source in Northwest Institute of Nuclear Technology. The uncertainties of experimental data are discussed in detail. In the end, the sensitivity of the detector to gamma rays versus the film thickness and the voltage of photomultiplier tube is provided as well. (authors)