[en] The preliminary study on the principle and feasibility of remote sensing monitoring system for nuclear hit is introduces. The monitoring method of incorporate optical imaging and exposure gage, of acoustic sensor array are brought forward. The accuracy which maybe reach is analyzed also

[en] Highlights: • Preparation ofAg/AgCl microrods by reaction of Ag₂WO₄ microrods with NaCl solution. • Generation of metallic Ag is induced by the ambient light in the synthesis process. • Ag/AgCl shows excellent visible light-driven photodegradation of organic dyes. - Abstract: Ag/AgCl microrods, aggregated by nanoparticles with a diameter ranging from 100 nm to 2 μm, were prepared by an ion-exchange reaction at 80 °C between Ag₂WO₄ template and NaCl solution. The existence of metallic Ag species was confirmed by XRD, DRS and XPS measurements. Ag/AgCl microrods showed excellent photocatalytic activity for the degradation of rhodamine B and methylene blue under visible light irradiation. The degradation rate constants of rhodamine B and methylene blue are 0.176 and 0.114 min⁻¹, respectively. The cycling photodegradation experiments suggest that Ag/AgCl microds could be employed as stable plasmonic photocatalysts for the degradation of organic dyes under visible light irradiation

[en] The first excited state energy, excitation energy and transition frequency of a strong-coupling polaron in a symmetric RbCl quantum dot (SRQD) are obtained by employing the linear combination operator and unitary transformation methods. Effects of temperature and confinement strength are taken into account. It is found that the first excited state energy, excitation energy and transition frequency are increasing functions of temperature and confinement strength.

[en] In this paper, the photoneutron characteristics of a research reactor (with heavy water as the moderator) at low power level are calculated by the MCNP program and the ORIGEN-ARP program. The nuclear measuring system of this reactor is taken as an example to study the formation mechanism of 'blind zone' in reactor startup due to low intensity of photoneutron. The analysis results show that the photo neutron intensity is approximate to 1 × 10⁹ n/s within 50 days after shutdown. 150 days later after the shutdown, the nuclear measuring system will not be able to detect the in-core neutron level variation under the critical and subcritical states, causing the formation of 'blind zone'. 200 days later after the shutdown, the photoneutron intensity is approximate to l × l0⁷ n/s. (authors)

[en] [Background] Plate-type fuel element exhibits excellent irradiation properties in research reactor while the grid spacing between the fuel element plates is usually very small. Most of the blockage accidents are caused by foreign matters entering the flow channel or fuel swelling due to the narrow coolant flow channel in the core. [Purpose] This study aims to analyze the process of blockage accidents, and put forward effective preventive measurements and detection methods. [Methods] Based on the investigation of some typical accidents abroad, China advanced research reactor (CARR) was taken as a feature research object, and the thermal hydraulic simulation calculation of CARR core, reactor body, single fuel assembly and cooling circuit outside the reactor was carried out by using the RELAP5/MOD3.2 thermal calculation program. Modeling and analysis of the specific flow channel blockage accident process on CARR was finished. [Results] Simulation results show that the temperature of the fuel assembly in the blocked flow passage will increase when the reactor power is raising, then the coolant will begin to boil, and the power will fluctuate significantly. [Conclusions] It is necessary to strictly control the quality of core operation. The monitoring of neutron flux rate and reactor power, and analyzing fuel temperature are helpful to detect and prevent the further development of the blockage accident. (authors)

[en] In this paper, ORIGEN-ARP program is used to calculate the in-core γ source intensity after shutdown of heavy water reactor, then the variation of photo neutron source intensity level after shutdown is calculated through the correlation of D (γ, n) H reaction rate and γ source intensity. The results show that the photo neutron source intensity 1900 days after shutdown is about 7.2 × 10⁶ n/s, which is higher than the additional Am-Be source intensity for the first criticality, so no additional neutron source is required for physical startup. (authors)

[en] [Background] The Multi-purposes heavy water research reactor (MHWRR) at the Birine Nuclear Research Center in Algeria had been upgraded. Its instrumentation, control and electrical system had been upgraded and fission molybdenum radiation apparatus were installed in the reactor core. First critical startup at very low photoneutron level after MHWRR upgrade is of great significance to the reactor modernization, marking the completion of the upgrading project. [Purpose] This study aims to fulfill successful critical startup of the reactor without additional neutron source, solve the problem of nuclear measurement blind area, and ensure the startup safety of the MHWRR after long period shutdown. [Methods] Based on the theoretical calculation and analysis of the residual photoneutron source intensity, the nuclear measurement blind area and the critical control rod height, a critical startup experiment scheme was put forward. The experiment was carried out in full accordance with the expectation of theoretical design in the absence of reference data, and nuclear power parameters were effectively monitored. [Results] The measuring data range of startup monitoring devices are well connected with the original monitoring ionization chambers outside the reactor core, and the error between theoretical value of critical control rods position and experimental value is less than 0.84%. [Conclusions] Successful critical startup and the agreement between the experimental results and the theoretical results show that the experiment technique for critical startup of MHWRR is reasonable and feasible. (authors)

[en] Artificial intelligence and big data technology are the research hotspots in various fields. This paper explores its application in the field of nuclear power based on artificial intelligence and big data technology. Firstly, based on the significance of artificial intelligence and big data technology for the development of nuclear power, this paper summaries the application status of artificial intelligence and big data technology in the field of nuclear power both at home and abroad. Then, the construction ideas and contents of artificial intelligence and big data technology in the field of nuclear power are analyzed. Secondly, the key technologies and core applications of artificial intelligence and big data in the field of nuclear power are clarified. Finally, suggestions are put forward to support the application and development of artificial intelligence and big data technology from a strategic perspective. (authors)

[en] In diagnostic nuclear medicine, the used of radioactive drugs with ionizing radiation effect and may place nuclear medicine workers and patients at risk of infection in terms of health. In this review the global trends in diagnostic nuclear medicine modalities applied in medical procedure were introduced at first. And then the exposure dose of nuclear medicine workers and patients in different examination items were analyzed emphatically. The radiation protection status was evaluated based on the analysis. In recent years, the researches in nuclear medicine radiation protection showed that the annual effective dose of workers was less than yearly dose limit of occupational exposure. The effective dose was mainly from single photon radiopharmaceuticals labeled by ⁹⁹Tc^m for patients undergoing SPECT examinations. However for PET/CT examinations, the effective dose was mainly from CT procedure. It could significantly reduce the effective dose to the patients when the activity of radioactive drugs and CT acquisition conditions were selected appropriately. (authors)

[en] The quality of semiconductor p-n junctions and substrates is essential for a reliable performance of microelectronic devices. The imaging techniques of ion beam induced charge (IBIC) and ionoluminescence (IL) are applied to image and analyze light emitting diodes (LEDs). The LEDs have been imaged both from the front (beam normal to p-n junction plane) and from the transverse direction (beam parallel to p-n junction plane). The imaging techniques provide details on the structural uniformity of the p-n junction and the light emitting properties, as stimulated by proton irradiation. Following IBIC and IL analysis, PIXE and RBS provide elemental distribution information on the metal layers and other components in the LEDs. The techniques which can be utilized by the nuclear microprobe potentially provide powerful tools for the failure analysis and quality control of the fabrication of microelectronic devices