摘要：Small long-life transportable high temperature gas-cooled reactors(HTRs) are interesting because they can safely provide electricity or heat in remote areas or to industrial users in developed or developing *** paper presents the neutronic design of the U-Battery,which is a 5 MWth block-type HTR with a fuel lifetime of 5–10 *** a reactor pressure vessel diameter of less than 3.7 m,some possible reactor core configurations of the 5 MWth U-Battery have been investigated using the TRITON module in SCALE *** neutronic analysis shows that Layout 12×2B,a scattering core containing 2 layers of 12 fuel blocks each with 20% enriched235U,reaches a fuel lifetime of 10 effective full power years(EFPYs).When the diameter of the reactor pressure vessel is reduced to 1.8 m,a fuel lifetime of 4 EFPYs will be achieved for the 5 MWth U-Battery with a 25-cm thick graphite side *** 6×3 and 6×4 with a 25-cm thick BeO side reflector achieve a fuel lifetime of 7 and 10 EFPYs,*** comparison of the different core configurations shows that,keeping the number of fuel blocks in the reactor core constant,the annular and scattering core configurations have longer fuel lifetimes and lower fuel cost than the cylindrical ***,for the 5 MWth U-Battery,reducing the fuel inventory in the reactor core by decreasing the diameter of fuel kernels and packing fraction of TRISO particles is more effective to lower the fuel cost than decreasing the 235U enrichment.

摘要：The detection of low-level light is a key technology in various experimental scientific studies. As a photon detector, the silicon photomultiplier （SiPM） has gradually become an alternative to the photomultiplier tube （PMT） in many applications in high-energy physics, astroparticle physics, and medical imaging because of its high photon detection efficiency （PDE）, good resolution for single-photon detection, insensitivity to magnetic field, low operating voltage, compactness, and low cost. However, primarily because of the geometric fill factor, the PDE of most SiPMs is not very high; in particular, for those SiPMs with a high density of micro cells, the effective area is small, and the bandwidth of the light response is narrow. As a building block of the SiPM, the concept of the backside-illuminated avalanche drift detector （ADD） was first proposed by the Max Planck Institute of Germany eight years ago; the ADD is promising to have high PDE over the full energy range of optical photons, even ultraviolet light and X-ray light, and because the avalanche multiplication region is very small, the ADD is beneficial for the fabrication of large-area SiPMs. However, because of difficulties in design and fabrication, no significant progress had been made, and the concept had not yet been verified. In this paper, preliminary results in the design, fabrication, and performance of a backside-illuminated ADD are reported; the difficulties in and limitations to the backside-illuminated ADD are analyzed.

摘要：In an effort to find highly efficient ligands for hepatic asialoglycoprotein receptor （ASGPR）, four cluster galactosides with different scaffolds were synthesized in this paper. The affinity of these compounds for ASGPR was analyzed by binding study in vitro. The results showed that trivalent cluster galactosides behaved better than divalent analogues and the cluster galactosides with aryl groups on their scaffolds presented better binding affinity than those with aliphatic chain scaffolds.

摘要：In a poloidal field （PF） converter module, fuse protection is of great importance to ensure the safety of the thyristors. The fuse is pre-selected in a traditional way and then verified by finite element analysis. A 3D physical model is built by ANSYS software to solve the thermal- electric coupled problem of transient process in case of external fault. The result shows that this method is feasible.

摘要：The DC busbar is an important component for the ITER PF converter module to connect the converter and the reactor. This paper analyzes different cross-sections and different thermodynamic properties under natural-cooling and water-cooling conditions, and simulation is carried out by the software of the finite element method （FEM）. The result of the analysis shows that the water-cooling method is the better choice for the DC busbar.

摘要：The coolant pump impeller casting is the only rotating component in the nuclear island of an AP1000 nuclear power station, and is required to have a 60-year service time, which requires advanced materials and processing technologies to guarantee. In this paper, the casting process was studied, designed and modified by means of numerical simulation. The gating system was distributed symmetrically and the runner diameter was a little bigger for avoiding sand wash and turbulence;the feeding system focused on the solution of blades feeding, as some parts of which should reach Severity Level 1 radioactive testing standard. Therefore, upper and lower plates cooperating with chillers acted as feeding method besides additional 2-3 times thickness;in addition, lowering sand core strength, decreasing pouring temperature and increasing dimension allowance would be adopted to avoid crack defects. Finally, the pilot impeller was cast. The results show that the casting process design is reasonable, as the liquid rises very smoothly when pouring, and no volume defects are found by means of 100% radioactive testing. Based on this casting process, 16 coolant pump impellers have been successfully produced and delivered to customers.

摘要：Commercial3D reticular nickel foam and its composite structure were investigated on the sound absorption *** absorption performance of foam plates1?5layers(1-layer thickness:2.3mm;porosity:89%;average pore-diameter:0.57mm)was found to be poor,and could be improved by adding backed cavum or front perforated thin *** absorption coefficient could reach about0.4at1000-1600Hz for the composite structure of5-layer foam with a backed5mm-thick cavum,and even0.68at about1000Hz for that of2-layer foam with the same cavum and a perforated plate closely in front of the foam.

摘要：A synchrotron-based proton therapy(PT)facility that conforms with the requirement of future development trend in compact PT can be operated without an energy selection *** article demonstrates a novel radiation shielding design for this *** FLUKAbased Monte Carlo simulations have been performed to validate its *** this design,two different shielding scenarios(3-m-thick concrete and 2-m-thick iron–concrete)are proved able to reduce the public annual dose to the limit of 0.1 mSv/*** calculation result shows that the non-primary radiation from a PT system without an inner shielding wall complies with the IEC 60601-2-64 international standard,making a single room a ***,the H/D value of this design decreases from 2.14 to 0.32 mSv/Gy when the distance ranges from 50 to 150 cm from the isocenter,which is consistent with the previous result from another *** establishing a typical time schedule and procedures in a treatment day for a single room in the simulation,a non-urgent machine maintenance time of 10 min after treatment is recommended,and the residual radiation level in most areas can be reduced to 2.5 lSv/*** annual dose for radiation therapists coming from the residual radiation is 1 mSv,which is 20%of the target *** general,this shielding design ensures a low cost and compact facility compared with the cyclotron-based PT system.

摘要：A reasonable design strategy to improve the utilization of noble metal electrocatalysts for the hydrogen evolution reaction(HER)is crucial to simplify the process flow and accelerate the future renewable energy ***,abundant defects were created on 2.4-nm Ru nanoparticles to achieve unprecedently high mass-specific reactivity in harsh acidic and alkaline *** obtained defect-enriched Ru(DR-Ru)exhibits an ultrahigh HER turnover frequency of16.4 s^(-1)with a 100-mV overpotential in alkaline media,and it also retains an excellent value of 20.6 s^(-1)in acidic media;these results are superior to those reported for other Ru ***,a record-low loading of 2.5μg cm^(-2)for the DR-Ru catalysts and low overpotentials of 28.2 and 25.1 mV at10 mA cm^(-2)can be realized in alkaline and acidic media,***,the less coordinated Ru surface sites and partial lattice oxygen introduction weaken the bonding between H and DR-Ru catalysts,facilitate fast acidic HERkinetics and help dissociate the water molecule to overcome the major challenge of HER in alkaline electrolytes,leading to an activity comparable to that under acidic *** result provides a guideline for defect engineering on noble metal nanocatalysts to effectively improve the utilization of the catalysts and optimize reactivities.

摘要：A kind of surface instability,basin-like depression defect companied by mixed grain structure at the bottom of large-scale valve during electric upsetting process,would significantly influence the microstructures and mechanical properties of *** order to analyze the forming process of the basin-like depression defect,a finite element model for the electric upsetting process of Ni80A superalloy was developed using multi-field and multi-scale coupling analysis ***,a series of parameters loading path schemes for force and current were designed by varying the initial value,peak value and value level,and their effects on basin-like depression and mixed grain structure were simulated and *** is concluded that the changes of heating speed and pressurization speed result in the different flow velocities between the inner and outer layers of billet,thus exerting the basin-like *** results also indicate that these defects can be optimized through the parameter coordination between force and ***,the validity and reliability of the finite element model were verified by physical experiments in electric upsetting process.