The new accelerator project （ HIRFL-CSR ） constructed at the Heavy Ion Research Facility in Lanzhou （HIRFL） is approaching completion. It is a multipurpose cooler-storage-ring system, consisting of a maim ring （C...The new accelerator project （ HIRFL-CSR ） constructed at the Heavy Ion Research Facility in Lanzhou （HIRFL） is approaching completion. It is a multipurpose cooler-storage-ring system, consisting of a maim ring （CSRm）, an experimental ring （CSRe） and two transfer beam lines. The UHV system of CSRm is the most representative subsystem in the project. To minimize the beam loss due to charge exchange of the heavy ions with the residual gas molecules, the pressure of the CSRm vacuum system should reach 3.5 × 10^-9 Pa （N2 equivalent） and the pressure of 8 × 10^-10 Pa is expected for very heavy ion such as uranium to make its lifetime longer than 50 s in the ring. Now, the vacuum system of CSRm has been completed and a pressure less than 5 × 10^-10 Pa has been obtained. In this paper the layout of the CSRm vacuum system, the vacuum equipment in CSRm, the treatment method for the CSRm vacuum chambers, and the installation and operation of the system will be reported.展开更多
In this paper, by using an ingenious method, the hydrogen isotope solubilities and diffusivities in GWHER-1 stainless steel have been determined by a vacuum heating degassing approach at the temperature range of 597-1...In this paper, by using an ingenious method, the hydrogen isotope solubilities and diffusivities in GWHER-1 stainless steel have been determined by a vacuum heating degassing approach at the temperature range of 597-1022 K on a set of specimens with different sizes previously charged for 24 h under a hydrogen isotope pressure of 105 Pa in the temperature range of 800-1000 K. The permeabilities are then derived from the relation Φ = DKs. It is found D = 1.52 ×10^-6exp（-54100/RT）, Ks = 2.2×10^-exp（-5400/RT） and Φ = 3.3 ×10^-12exp（-59500/RT） for hydrogen, where Ks （Sieverts＇ constant） is given in Pa^-1/2, D in m2.s^-1.Pa^-1/2, T in K and R=8.31 J.mol^-1.K^-1. By taking isotope effects into account, the corresponding Arrhenius relations for deuterium and tritium are also deduced.展开更多
文摘The new accelerator project （ HIRFL-CSR ） constructed at the Heavy Ion Research Facility in Lanzhou （HIRFL） is approaching completion. It is a multipurpose cooler-storage-ring system, consisting of a maim ring （CSRm）, an experimental ring （CSRe） and two transfer beam lines. The UHV system of CSRm is the most representative subsystem in the project. To minimize the beam loss due to charge exchange of the heavy ions with the residual gas molecules, the pressure of the CSRm vacuum system should reach 3.5 × 10^-9 Pa （N2 equivalent） and the pressure of 8 × 10^-10 Pa is expected for very heavy ion such as uranium to make its lifetime longer than 50 s in the ring. Now, the vacuum system of CSRm has been completed and a pressure less than 5 × 10^-10 Pa has been obtained. In this paper the layout of the CSRm vacuum system, the vacuum equipment in CSRm, the treatment method for the CSRm vacuum chambers, and the installation and operation of the system will be reported.
基金Project supported by the National Natural Science Foundation of China （Grant No 10275017）.
文摘In this paper, by using an ingenious method, the hydrogen isotope solubilities and diffusivities in GWHER-1 stainless steel have been determined by a vacuum heating degassing approach at the temperature range of 597-1022 K on a set of specimens with different sizes previously charged for 24 h under a hydrogen isotope pressure of 105 Pa in the temperature range of 800-1000 K. The permeabilities are then derived from the relation Φ = DKs. It is found D = 1.52 ×10^-6exp（-54100/RT）, Ks = 2.2×10^-exp（-5400/RT） and Φ = 3.3 ×10^-12exp（-59500/RT） for hydrogen, where Ks （Sieverts＇ constant） is given in Pa^-1/2, D in m2.s^-1.Pa^-1/2, T in K and R=8.31 J.mol^-1.K^-1. By taking isotope effects into account, the corresponding Arrhenius relations for deuterium and tritium are also deduced.
