[en] The procedure of continuous operation at full power and some operation experience for 5 MW Low Power Reactor are summarized. The results show that this reactor possesses satisfactory feature and enough safety margin

[en] The set up of abnormal events database for the High Flux Engineering Test Reactor (HFETR) is described, and its abnormal event are counted analyzed. The results show that the main abnormal events include reactor control and protection system breakdown, reactor coolant system breakdown and others breakdown. These three breakdowns make up about 86.09% of the total events. But the influence of they on the reactor safety is not clear

[en] In this study, the effect of different pre-treatment techniques (sandblasting, micro-arc oxidation and laser ablation) on interlaminar strength, failure mode and galvanic corrosion resistance of FMLs based on aluminum alloy 5083 was comprehensively investigated by utilizing the peeling test and an immersion test. The results show that micro-arc oxidation and laser ablation can greatly enhance the Mode I (peel) interlaminar strength of FMLs based on 5083 aluminum by 67.2% and 80.8% respectively, compared with traditional sandblasting methods. For the FMLs treated with sandblasting, it mainly shows adhesive failure between epoxy and aluminum alloys, while the cohesive failure became dominant failure modes for micro-arc oxidation treated and the laser treated specimen. In addition, compared with mechanical treatment of sandblasting, micro-arc oxidation and laser ablation can significantly improve the galvanic corrosion resistance of FMLs by forming an isolated layer consisting of aluminum oxide between carbon fiber and aluminum substrate. (paper)

[en] The uneven temperature field caused by the local instantaneous heating of the laser generates the thermal stress during the selective laser sintering. The stress causes the deformation of parts, affecting the precision and mechanical properties. However, it’s difficult to directly measure the stress history and deformation behavior during processing through experimental methods due to its ultra-high temperature and closed cavity. In this paper, the effects of laser power and scanning speed on the stress field and deformation of polyamide 6 by selective laser sintering were systematically investigated. The results showed that as the laser power increased or the scanning speed decreased, the z-direction stress and deformation of the specimens increased. Based on the inherent strain method, the deformation behavior of large-size parts was evaluated and in good agreement with experiments, which can guarantee the accuracy of the model and predict the deformation of parts. (paper)

[en] During the selective laser sintering process, the sintering behavior between powders is mainly affected by thermal effect. There are a large number of process parameters influencing the variation of temperature and molten pool, of which the laser density and scanning speed play a crucial role in determining the performance of the parts. In this paper, the effects of laser density and scanning speed on the precision and strength of polyamide 6 selective laser sintering parts were systematically investigated. The results show that with the increase of energy density, the positive dimensional deviation of the parts in three directions increases gradually, and the tensile strength increases at beginning and then decreases. When the laser power and scanning speed were changed, the tensile strength of the parts varied between 5.62 MPa and 58.74 MPa. (paper)

[en] In the past few decades, great attention has been paid to the development of IV–VI semiconductor colloidal quantum dots, such as PbSe, PbS and PbSSe, in infrared (IR) photodetectors due to their high photosensitivity, solution-processing and low cost fabrication. IR photodetectors based on field-effect transistors (FETs) showed high detectivity since the transconductance can magnify the drain–source current under certain applied gate voltages. However, traditional lateral FETs usually suffer from low photosensitivity and slow responsivity, which restricts their widespread commercial applications. In this work, therefore, novel vertical FET (VFET) based photodetectors are presented, in which the active layer is sandwiched between porous source electrode and planar drain electrode, resulting to ultrashort channel length. In this way, enhanced photoresponsivity and specific detectivity of 291 A W⁻¹ and 1.84 × 10¹⁴ Jones, respectively, can be obtained at low drain–source voltage (V _DS) of −1 V and gate voltage (V _g) of −2 V under 100 μW cm⁻² illumination intensity, which was better than that of the traditional lateral FET based photodetectors. Therefore, it is promising to fabricate broadband photodetectors with high performance and good stability by this easy approach. (paper)

[en] Recently, great attention has been paid to IV–VI colloidal quantum dots (CQDs) for their high photosensitivity, solution processability and low cost. Also, metal halide perovskites are very promising materials to realize the high-performance solution-processed visible-light photodetectors due to their cost-effective manufacturing, tunable absorption and photoluminescence in whole visible spectrum. In this paper, we present solution-processed CQDs-based tandem broadband photodetectors with low dark-current and high-sensitivity by inserting dielectric Polymethyl methacrylate (PMMA) interlayer between two sub-detectors. Our experimental data showed that the tandem broadband photodetector ITO/PEDOT:PSS/CsPbBr₃:PbS_0.4Se_0.6/ZnO/PVK/CsPbBr₃:PbS_0.4Se_0.6/ZnO/Au showed a maximum specific detectivity of 6.8 × 10¹³ Jones with a responsivity of 27 A W⁻¹ under 57.8 μW cm⁻² 980 nm illumination. The device performance can be further enhanced by inserting a 50 nm dielectric PMMA layer between the two sub-photodetectors. As the result, the tandem photodetector ITO/PEDOT:PSS/CsPbBr₃:PbS_0.4Se_0.6/ZnO/PMMA(50 nm)/PVK/CsPbBr₃:PbS_0.4Se_0.6/ZnO/Au exhibits a maximum specific detectivity of 1.32 × 10¹⁴ Jones with a responsivity of 27.72 A W⁻¹ under 57.8 μW cm⁻² of 980 nm laser. Further, the physical mechanisms for the enhanced performance are discussed in detail. (paper)

[en] Highlights: • The coupling of T300/648 and Mg–Li shows a large driving force for galvanic corrosion. • The galvanic activity of T300/648 coupled to Mg–Li increases with the increase of Li. • The duration of the current instability in T300/648 and magnesium coupling increases with the increase of Li. • The micro-arc oxidation film with double-layer exhibit good inhibiting effect on galvanic corrosion. - Abstract: The galvanic corrosion behaviour of carbon fibre reinforced polymer (CFRP, T300/648) in contact with different magnesium alloys (AZ31, LZ91 and LZ141) in a sodium chloride solution and the influence of micro-arc oxidation (MAO) film on the corrosion behaviour of CFRP/magnesium alloys coupling were investigated using the electrochemical method. The results showed that the galvanic activity of CFRP/magnesium alloys coupling increased with the increase of lithium concentrations. The duration of the inhibitory effect of MAO film on the corrosion of CFRP/Mg–Li coupling is longer than that of CFRP/Mg–Al coupling due to its double-layer structure