摘要：To upgrade Hefei Light Source(HLS) Linac, eight accelerating units have been constructed to realize fullenergy injection of the storage ring. Each of the units consists of two 3-m accelerators driven by one *** input cavity detuning method was developed to measure and correct the phase length of the RF power distribution waveguide system. The design of the waveguide network and the principles of the detuning method are presented in this paper. After correction, the phase error between the waveguide of the two accelerators was less than ±0.5?, and the maximum electron energy of Linac reached 805 MeV, which is very near the theoretical maximum value of 810 MeV. These results demonstrate that the calibration of the waveguide was successful.

摘要：To develop a high-power continuous-wave terahertz source, a Clinotron operating at 0.3 THz is investigated. Based on the analyses of field distribution and coupling impedance, the dispersion characteristic of a rectangular resonator is preliminarily studied. The effective way to select fundamental mode to interact with the electron beam is especially ***, the structure is optimized by particle-in-cell simulation, and the problems of manufacture tolerance, current density threshold, and heat dissipation during Clinotron’s operation are also discussed. The optimum device can work with a good performance under the conditions of 8 k V and 60 m A. With the generation of signal frequency at 315.89 GHz and output power at 12 W on average, this device shows great prospects in the application of terahertz waves.

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：An S-band cavity BPM is designed for a new injector in National Synchrotron Radiation laboratory. A re-entrant position cavity is tuned to the TM110 mode as position cavity. Cut-through waveguides are used as pickups to suppress the monopole signal. Theoretical resolution of this design is 31 nm. A prototype cavity BPM system is manufactured for off-line cold tests. The wire scanning method is used to calibrate the BPM and estimate the performance of the on-line BPM system. A cross-talk problem has been detected during the cold test. Racetrack cavity BPM design can be used to suppress the cross-talk. With the nonlinear effect being ignored, transform matrix can be used to correct cross-talk. Analysis of cold test results shows that the position resolution of prototype BPM is better than 3 μm.

摘要：Based on the first ionization chamber （IC） prototype, the structure, working gas component and electrode material of the IC are improved. The test of the improved IC shows that the plateau length is about 2000 V, the plateau slope is less than 0.2%/100 V, the sensitivity is 19.6 pA/rad·h 1, the up-limitation of the linearity can be up to 3.6×105 rad/h, and the applied voltage can be operated to 3500 V. The test results show that the performance of the improved IC meets the requirements of the beam loss monitor.

摘要：Three-dimensional graphene/conducting polymer（3DGCP） composites have received significant attention in recent years due to their unique structures and promising applications in energy *** the structural diversity of graphene and π-functional conducting polymers via rich chemical routes,a number of 3DGCP composites with novel structures and attractive performance have been ***,the hierarchical porosity,the interactions between graphene and conducting polymers as well as the their synergetic effects within 3DGCP composites can be well combined and elaborated by various synthetic methods,which made 3DGCP composites show unique electrochemical properties and significantly improved performance in energy storage fields compared to other graphenebased *** this short review,we present recent advances in 3DGCP composites in developing effective strategies to prepare 3DGCP composites and exploring them as a unique platform for supercapacitors with unprecedented *** challenges and future opportunities are also discussed for promotion of further study.

摘要：The efficient and safe operation of large fusion devices strongly relies on the plasma configuration inside the vacuum *** is important to construct the proper plasma equilibrium with a desired plasma *** order to construct the target configuration,a shape constraint module has been developed in the tokamak simulation code（TSC）,which controls the poloidal flux and the magnetic field at several defined control *** is used to construct the double null,lower single null,and quasi-snowflake configurations for the required target shape and calculate the required PF coils *** flexibility and practicability of this method have been verified by the simulated results.

摘要：A high Si reduced activation ferritic/martensitic(RAFM) steel for nuclear structure application is successfully designed by using Calphad method. The main designed chemical composition is C 0.18–0.22%, Cr10.0–10.5%, W 1.0–1.5%, Si 1.0–1.3%, V+Ta 0.30–0.45%, and Fe in balance. High Si design brings excellent corrosion resistance, while low activation is advantageous in the nuclear waste processing. The experimental results indicate that the newly designed high Si RAFM steel had full martensitic structure and uniformly distributed fine second phase particles, and exhibited excellent mechanical properties and corrosion resistance. Compared to the P91 steel, this new RAFM steel designed by Calphad method is expected to be a promising candidate used in nuclear power generation, which also provides a new and effective approach to the development of RAFM steel for nuclear application.

摘要：The Alpha Magnetic Spectrometer(AMS) is an instrument for the international scientific experiment,composed of six detectors and 650 *** objective of AMS experiment is to search for dark matter and anti-matter in *** this paper,the thermal control system for AMS cryocoolers is designed,analyzed and experimentally *** loop heat pipes(LHPs) as the main heat dissipation component,the thermal control system has sufficient heat dissipation capability to prevent the cryocoolers from over temperature(+40℃) in hot environment,meanwhile to ensure temperatures of the cryocoolers higher than their lower limit(-20℃) in cold *** results show that the thermal control system for AMS cryocoolers functions stably satisfying design specification.

摘要：Flow rate and temperature are important parameters for design and operation of liquid lead–bismuth(Pb Bi) experimental loop. The PREKY facility was designed to study test technique of flow rate and local temperature of Pb Bi loop. In this work, flow rate monitoring of molten Pb Bi was performed, and temperatures of the Pb Bi and pipe surface were measured. The results show that the flow rate of the venturi-nozzle flow meter had an uncertainty of ±5 % in the range of 0.6–2.0 m/s, and the maximum temperature difference between the Pb Bi and pipe surface was about 8 ℃.