Bystander effects induced by low-dose or low dose-rate radiation have put a great challenge to the tradi- tional model for radiation protection. In order to get a better assessment of the adverse effects of radiation,...Bystander effects induced by low-dose or low dose-rate radiation have put a great challenge to the tradi- tional model for radiation protection. In order to get a better assessment of the adverse effects of radiation, especially the low-dose radiation risk in environment, a radioactive irradiation facility, by which the dose and dose-rate to the biological targets can be controlled by rotating the sample bracket and changing the space between the radioactive source and the targets, was developed. The energy of our α-radioactive source (241Am) is measured averagely 3.5 MeV at the position of the irradiated sample. The dose rate was measured by using a silicon surface barrier detector and a CR39 particle track detector. A dose rate ranging from 0.045 cGy/s to 1.07 cGy/s can be obtained by changing the space length from the radioactive source to the sample dish.展开更多
A single-particle microbeam facility has been constructed at the Key Laboratory of Ion Beam Bioengi- neering (LIBB), Chinese Academy of Sciences (CAS). The system was designed to deliver a defined numbers of hydro- ge...A single-particle microbeam facility has been constructed at the Key Laboratory of Ion Beam Bioengi- neering (LIBB), Chinese Academy of Sciences (CAS). The system was designed to deliver a defined numbers of hydro- gen ions, produced by a van de Graaff accelerator, in an en- ergy range of 2.0—3.0 MeV, into an area smaller than that of the nucleus of an individual living cell. The beam is colli- mated by a borosilicate glass capillary that forms the beam-line exit. An integrated computer program recognizes the cells and locates them one by one over the microbeam exit for irradiation. We present technical details of the CAS-LIBB microbeam facility, particularly on the collimator, hardware, control program, as well as cell irradiation proto- cols available. Various factors contributing to the targeting and positioning precision are discussed along with accuracy measurement results.展开更多
基金Supported by the National Natural Science Foundation of China(No.30070192)and he National Science Fund for Distinguished Young Scholars(No.10225526).
文摘Bystander effects induced by low-dose or low dose-rate radiation have put a great challenge to the tradi- tional model for radiation protection. In order to get a better assessment of the adverse effects of radiation, especially the low-dose radiation risk in environment, a radioactive irradiation facility, by which the dose and dose-rate to the biological targets can be controlled by rotating the sample bracket and changing the space between the radioactive source and the targets, was developed. The energy of our α-radioactive source (241Am) is measured averagely 3.5 MeV at the position of the irradiated sample. The dose rate was measured by using a silicon surface barrier detector and a CR39 particle track detector. A dose rate ranging from 0.045 cGy/s to 1.07 cGy/s can be obtained by changing the space length from the radioactive source to the sample dish.
文摘A single-particle microbeam facility has been constructed at the Key Laboratory of Ion Beam Bioengi- neering (LIBB), Chinese Academy of Sciences (CAS). The system was designed to deliver a defined numbers of hydro- gen ions, produced by a van de Graaff accelerator, in an en- ergy range of 2.0—3.0 MeV, into an area smaller than that of the nucleus of an individual living cell. The beam is colli- mated by a borosilicate glass capillary that forms the beam-line exit. An integrated computer program recognizes the cells and locates them one by one over the microbeam exit for irradiation. We present technical details of the CAS-LIBB microbeam facility, particularly on the collimator, hardware, control program, as well as cell irradiation proto- cols available. Various factors contributing to the targeting and positioning precision are discussed along with accuracy measurement results.