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Public acceptance has become the most critical question for sustainable development of nuclear energy in recent decades. Many researches concentrated on risk and benefit perception, which were deemed as the most influential factors of Public Acceptance of Nuclear Energy (PANE). But few researches focused on psychological factors including regulatory focus. Therefore, this paper aimed to explore the moderating effect of regulatory focus on PANE based on Regulatory Focus Theory in order to find ways to increase/decrease PANE. An Internet-based survey had been carried out in China nationwide. The results indicated that trust in government was positively related to PANE and this relationship was mediated by risk and benefit perception. In addition, the strength of the associations between risk and benefit perception and PANE were moderated by regulatory focus, consisting of prevention focus and promotion focus. Prevention focus strengthened the negative relationship between risk perception and PANE, while promotion focus weakened. Moreover, promotion focus weakened the positive relationship between benefit perception and PANE, but no significant moderating effect of prevention focus was founded on the relationship between benefit perception and PANE. Some policy implications were also proposed on the basis of above-mentioned findings.

Traditional accurate radiotherapy includes accurate positioning, planning and delivery. With the development of adaptive radiotherapy techniques, it is necessary to accurately verify the dose delivered during and after the treatment. Based on the general demands in traditional accurate radiotherapy, a whole course of Four-Accuracies Radiotherapy was proposed, including accurate planning, accurate positioning, accurate delivery and accurate verification to guarantee an excellent match between the dose received by the patient and the expected dose. Furthermore, an accurate radiotherapy system KylinRay was developed to provide solutions for radiotherapy including Intensity-modulated Accurate Radiotherapy System (KylinRay-IMRT), Image-guided Accurate Positioning and Tracking System (KylinRay-IGRT), Dynamic Multi-Leaf Collimator System (KylinRay-DMLC), and Dose-guided Real-time Verification System (KylinRay-DGRT). In this paper, the architecture of KylinRay and each sub-system and the key technologies are introduced, and the key technologies are tested with international standards and clinical cases. The verification and validation results indicated that the function and performance of KylinRay can meet the needs of clinical practice.

AbstractAdvanced nuclear systems, such as fusion systems, generally have features of large size, complex structures, spatially heterogeneous distribution of components and materials, and high energy and high flux, as well as a wide and complex energy spectrum of neutrons. Compared with traditional nuclear systems, these features have brought unprecedented challenges to neutronics design and analysis. To confront these challenges, the FDS Team has made significant progress in the development of neutronics methods and the comprehensive simulation code Super Multi-functional Calculation Program for Nuclear Design and Safety Evaluation (SuperMC). Furthermore, the FDS Team has been developing the High Intensity D-T Fusion Neutron Generator (HINEG) and has performed a series of neutronics experiments. Based on the developed methods, codes, and facility, a series of fusion designs and analyses has been carried out, including the design of FDS series reactors as well as the ITER neutronics analysis.

Host–guest self-assemblies of methyl 5-bromo-2-(hexadecyloxy)benzoate (host) and 1-bromohexadecane (guest) molecules were investigated at the liquid/solid interface by scanning tunneling microscopy. Polar solvent (1-octanoic acid) and nonpolar solvents (1-phenyloctane, n-pentadecane, n-tetradecane, and n-decane) were selected to study the solvent effect on the self-assembly of the host–guest system. It is observed that the host–guest system self-assembles into different morphologies at low concentrations due to the solvent adsorption. Only a linear structure can be obtained at high concentration in different kinds of solvents. In particular, the different self-assembled patterns obtained at low concentration will eventually transform to the same linear structure. Owing to the participation of guest molecules, a strong Br···O═C halogen bond is formed between host and guest molecules, further leading to the occurrence of physisorbed monolayers and structural transition. The density functional theory calculations are performed to reveal the underlying mechanisms of halogen bond formation.

AbstractDose conversion coefficients are important physical quantities in radiation dosimetry assessment and can be derived from Monte Carlo simulation based on human computational phantoms. In order to accurately evaluate the dose to a human body especially for a Chinese female, a precise whole-body Chinese female computational phantom named Rad-Human was constructed based on high-resolution digital color slice images of an adult female body. Rad-Human includes 46 tissues and organs with a minimum voxel size of 0.15 × 0.15 × 0.25 mm for head and neck and 0.15 × 0.15 × 0.5 mm for other regions, and it contains more than 28.8 billion voxels. Conversion coefficients and effective doses of external radiation, specific absorbed fractions, and S values of internal radiation for different energies for Rad-Human were calculated. The calculated dose conversion coefficients were reasonable comparing and analyzing the relationship between dose and organ characteristics with those values of the International Commission on Radiological Protection (ICRP) reference phantom. Based on the information and simulation results of Rad-Human, a set of more complete data of dose conversion coefficients in the radiation field was constructed for a Chinese adult female. Dose discrepancies that were observed were due to differences of body structures between the two phantoms. The differences of dose conversion coefficients between Rad-Human and the ICRP reference phantom demonstrate that Rad-Human can more accurately assess the exposure dose especially for a Chinese female.

In 2011, the Chinese Academy of Sciences launched an engineering project to develop an accelerator-driven subcritical system (ADS) for nuclear waste transmutation. The China Lead-based Reactor (CLEAR), proposed by the Institute of Nuclear Energy Safety Technology, was selected as the reference reactor for ADS development, as well as for the technology development of the Generation IV lead-cooled fast reactor. The conceptual design of CLEAR-I with 10 MW thermal power has been completed. KYLIN series lead-bismuth eutectic experimental loops have been constructed to investigate the technologies of the coolant, key components, structural materials, fuel assembly, operation, and control. In order to validate and test the key components and integrated operating technology of the lead-based reactor, the lead alloy-cooled non-nuclear reactor CLEAR-S, the lead-based zero-power nuclear reactor CLEAR-0, and the lead-based virtual reactor CLEAR-V are under realization.

AbstractThe liquid LiPb blanket concept has become a promising design for fusion reactor in the world, and a series of fusion reactors with LiPb blankets have been designed by FDS team in China. To support the various designs and technologies of Chinese LiPb breeder blankets, LiPb experimental loops have been built to follow the different phases of LiPb blankets requirements and to achieve different testing functions. Three thermal convection loops named DRAGON-I, II, and III were built to carry out the compatibility experiments and validate the loop technology, and the multifunctional forced convection loops named DRAGON-IV and V were built or designed to validate the magnetohydrodynamic effect and thermal-hydraulics test. Three sets of He-LiPb dual-coolant auxiliary systems named DRAGON-VI, VII, and VIII were designed and proposed for testing test blanket modules in EAST, ITER, and DEMO blankets in the future. An overview on the design and construction of these loops is introduced in this paper, as well as some preliminary experiments done in the loops.

AbstractA Chinese dual-functional lithium lead test blanket module was proposed for testing in ITER. The flow channel insert (FCI) was inserted in LiPb flow channels to reduce magnetohydrodynamic (MHD) effects and to increase the outlet temperature of coolant LiPb. The FCI has a big influence on the LiPb flow characteristics under the high magnetic field. In this paper, the LiPb MHD flow characteristics both in the gap between the FCI and the channel wall and inside the FCI was numerically calculated using an MHD code named MTC-H 2.0 in a poloidal channel. The influence of the FCI on flow distribution was analyzed. The pressure drop was compared to the case without the FCI, and the pressure equalization was assessed for both sides of the FCI with pressure equalization openings. The impact of electrical conductivity of the FCI material was analyzed.

AbstractThe Monte Carlo method is a stochastic statistic algorithm. It is one of the most accurate dose calculation methods, but its application in clinic is limited because of the long computation time. Generally, to accelerate Monte Carlo simulation and reduce stochastic noise, a digital filtering technique is used to smooth a rough dose distribution (includes evident noise) to a satisfied one. Different types of filters have been applied, such as Gaussian filters, Savitzky-Golay filters, etc., but the ability of a single filtering filter is limited. Therefore, a hybrid filter combining those filtering techniques was used. Two types of mixture methods—parallel and cascade—with three-dimensional Gaussian and Savitzky-Golay filters were researched. In addition, a method that simplifies the mixture filter structure using an equivalent convolution kernel based on convolution theory was introduced. With simulation data from a standard phantom, the rough dose distributions and the dose distribution smoothed by the two types of mixture filters were compared with that of the “benchmark” one. Test results showed that the two types of mixture filters can suppress much of the noise added in Monte Carlo dose distributions and enhance its visualization. As for the research’s test cases, the filtering effect of the cascade mixture filter was slightly better than that of the parallel mixture filter. Filter combinations can provide favorable filtering effects. The filtering effects of different mixture methods are not uniform. The cascade mixture filter has a better filtering effect than the parallel mixture filter.

AbstractPhoton external radiotherapy of cancer takes advantage of the physical interaction of the photon and the secondary electron with biological tissue to kill cancer cells. The current linac is important equipment for producing an X-ray. The Monte Carlo method has been demonstrated to be the most accurate method for radiotherapy issues such as dose calculation and plan verification. However, its application in the clinic requires detailed information on the beam characteristics. A large quantity of the consumptive time for multiple simulation phases, such as linac treatment head simulation, beam trimmer module simulation, and patient/phantom simulation, and storage for the phase-space file (PSF), which records the information of the transported particle, are two knotty issues also. Therefore, a set of simple and convenient multiple source models (MSMs) including five subsources for regular fields from 3 × 3 cm to 30 × 30 cm was built, which is based on a VARIAN 2300C 6 MV-X beam simulated by the Monte Carlo code BEAMnrc and produced by BEAMnrc’s beam characteristics analysis utility BEAMDP (BEAM Data Processor). This MSM reduced the three simulation phases to one to effectively decrease the consumptive time. The storage issue about the PSF was also solved for MSM’s small volume. The dose distribution of the five-source model in a homogeneous phantom was compared with that of the full linac simulation and measurement data to verify reliability. The characteristics of the subsources were analyzed to present their feature. This work provided the base for implementing the Monte Carlo algorithm into the Accurate Radiotherapy System.

A radiation protection control system has been designed, based on distributed computers and consideration of the features of the radiation source of the HT-7U fusion experimental device, for protecting the workers and the public against neutron and photon radiation, and especially for ensuring that workers cannot unexpectedly enter an area of high radiation level in any case. A multi-subsystem (irradiation monitoring subsystem, access control subsystem, safety interlock subsystem and other related facilities) integration concept is proposed for the design. This system has been implemented on the basis of the up-to-date industrial field bus CAN, featuring simplicity and flexibility of installation and maintenance, capability for real-time long distance communication and multi-master protocol.

The motivation for developing fusion-fission hybrid reactors is discussed in the context of electricity power requirements by 2050 in China. A detailed conceptual design of the Fusion Experimental Breeder (FEB) was developed from 1986-1995. The FEB has a subignited tokamak fusion core with a major radius of 4.0 m, a fusion power of 145 MW, and a fusion energy gain Q of 3. Based on this, an engineering outline design study of the FEB, FEB-E, has been performed. This design study is a transition from conceptual to engineering design in this research. The main results beyond that given in the detailed conceptual design are included in this paper, namely, the design studies of the blanket, divertor, test blanket, and tritium and environment issues. In-depth analyses have been performed to support the design. Studies of related advanced concepts such as the waste transmutation blanket concept and the spherical tokamak core concept are also presented.

FENDL-2 , the latest version of Fusion Evaluated Nuclear Data Library, had been developed based on selection of evaluated data from ENDF/B-VI, JENDL-3, JENDL-FF, BROND-2 and EFF-3 and distributed for benchmark analysis recently. Integral data test of FENDL-2 has been performed to qualify and validate the working library with a variety of neutronic integral experiments. Calculations and analyses of neutron leakage spectra and reaction rates have been performed with the three dimensional Monte Carlo transport code MCNP and FENDL-2 data library. The results have been compared with the measured results as well as the results obtained previously with FENDL-1, EFF, JENDL-FF

AbstractA discrete ordinates nodal transport method has been developed for numerical solution of the one-dimensional neutron transport equation in curvilinear geometries. The nodal transport equation is solved by the Green’s function method, using the Legendre polynomial expansion for spatial dependence and the discrete ordinates (SN) approximation for angular dependence. The calculation for various test problems has been performed to verify the method. The numerical results demonstrate that it has very high precision on coarse spatial meshes relative to the standard fine-mesh SNmethod with the spatial diamond-differencing scheme.

AbstractThe fully exposed center conductor post (CCP) in a spherical tokamak will receive strong neutron irradiation. The analytical results for a CCP in a spherical tokamak reactor are given considering the irradiation effects such as radiation damage, transmutation, nuclear and resistive heat removal, induced radioactivity and blanket tritium breeding ratio, etc. These results are compared with those for the first wall of conventional tokamaks, assuming the same technical requirements.