An E//B neutral particle analyzer(NPA)has been designed and is under development at Sichuan University and Southwestern Institute of Physics.The main purpose of the E//B NPA is to measure the distribution function of ...An E//B neutral particle analyzer(NPA)has been designed and is under development at Sichuan University and Southwestern Institute of Physics.The main purpose of the E//B NPA is to measure the distribution function of fast ions in the HL-2A/3 tokamak.The E//B NPA contains three main units,i.e.the stripping unit,the analyzing unit and the detection unit.A gas stripping chamber was adopted as the stripping unit.The results of the simulations and beam tests for the stripping chamber are presented.Parallel electric and magnetic fields provided by a NdFeB permanent magnet and two parallel electric plates were designed and constructed for the analyzing unit.The calibration of the magnetic and electric fields was performed using a 50 kV electron cyclotron resonance ion source(ECRIS)platform.The detection unit consists of 32lutetium-yttrium oxyorthosilicate(LYSO)detector modules arranged in two rows.The response functions ofα,hydrogen ions(H^(+),H_(2)^(+)and H_(3)^(+))andγfor a detector module were measured with^(241)Am,^(137)Cs and^(152)Eu sources together with the 50 kV ECRIS platform.The overall results indicate that the designed E//B NPA device is capable of measuring the intensity of neutral hydrogen and deuteron atoms with energy higher than 20 keV.展开更多
The neutral particle analyzer(NPA)is one of the crucial diagnostic devices in a Tokamak facility.The stripping unit is one of the main parts of the NPA.A windowless gas-stripping room with two differential pipes has b...The neutral particle analyzer(NPA)is one of the crucial diagnostic devices in a Tokamak facility.The stripping unit is one of the main parts of the NPA.A windowless gas-stripping room with two differential pipes has been constructed in a parallel electric and magnetic fields(E//B)NPA.The pressure distributions in the stripping chamber are simulated by ANSYS Fluent together with MolFlow+.Based on the pressure distributions obtained from the simulation,the stripping efficiency of the E//B NPA is studied using GEANT4.Hadron reaction physics is modified to track the charge state of each particle in a cross-section-based method in GEANT4.The transmission rates(R)and stripping efficiencies f_(+1)are examined for particle energies ranging from 20 to 200 keV with the input pressure(P_(0)),ranging from 20 to 400 Pa.According to the combined global efficiency,R×f_(+1),P_(0)=240 Pa is obtained as the optimum pressure for the maximum global efficiency in the incident energy range investigated.展开更多
A test strip was developed to rapidly detect fluoroquinolones in foods by colloidal gold immunochromatography method in combination with a food safety analyzer. The results showed that the test strip has the detection...A test strip was developed to rapidly detect fluoroquinolones in foods by colloidal gold immunochromatography method in combination with a food safety analyzer. The results showed that the test strip has the detection sensitivity of 20 μg/L for enrofloxacin, sarafloxacin, difloxacin, ofloxacin, norfloxacin, ciprofloxacin, pefloxacin, flumequine and danofloxacin, and the detection sensitivity of 40 μg/L for enoxacin and oxolinic acid. The test strip consumes only 10 min for detection, and the false positive rate and the false negative rate are both zero. The test strip can accurately, reliably and easily detect residual fluoroquinolones in foods, and is suitable for on-site detection of a large number of samples.展开更多
基金supported by the National Magnetic Confinement Fusion Energy R&D Program of China(No.2018YFE0310200)National Natural Science Foundation of China(Nos.11705242,11805138 and 12175156)the Fundamental Research Funds for the Central Universities in China(Nos.YJ201820 and YJ201954)。
文摘An E//B neutral particle analyzer(NPA)has been designed and is under development at Sichuan University and Southwestern Institute of Physics.The main purpose of the E//B NPA is to measure the distribution function of fast ions in the HL-2A/3 tokamak.The E//B NPA contains three main units,i.e.the stripping unit,the analyzing unit and the detection unit.A gas stripping chamber was adopted as the stripping unit.The results of the simulations and beam tests for the stripping chamber are presented.Parallel electric and magnetic fields provided by a NdFeB permanent magnet and two parallel electric plates were designed and constructed for the analyzing unit.The calibration of the magnetic and electric fields was performed using a 50 kV electron cyclotron resonance ion source(ECRIS)platform.The detection unit consists of 32lutetium-yttrium oxyorthosilicate(LYSO)detector modules arranged in two rows.The response functions ofα,hydrogen ions(H^(+),H_(2)^(+)and H_(3)^(+))andγfor a detector module were measured with^(241)Am,^(137)Cs and^(152)Eu sources together with the 50 kV ECRIS platform.The overall results indicate that the designed E//B NPA device is capable of measuring the intensity of neutral hydrogen and deuteron atoms with energy higher than 20 keV.
基金This work was supported by the National MCF Energy R&D Program of China(No.MOST 2018YFE0310200)the National Natural Science Foundation of China(Nos.11805138 and 11705242)the Fundamental Research Funds For the Central Universities(Nos.YJ201820 and YJ201954)。
文摘The neutral particle analyzer(NPA)is one of the crucial diagnostic devices in a Tokamak facility.The stripping unit is one of the main parts of the NPA.A windowless gas-stripping room with two differential pipes has been constructed in a parallel electric and magnetic fields(E//B)NPA.The pressure distributions in the stripping chamber are simulated by ANSYS Fluent together with MolFlow+.Based on the pressure distributions obtained from the simulation,the stripping efficiency of the E//B NPA is studied using GEANT4.Hadron reaction physics is modified to track the charge state of each particle in a cross-section-based method in GEANT4.The transmission rates(R)and stripping efficiencies f_(+1)are examined for particle energies ranging from 20 to 200 keV with the input pressure(P_(0)),ranging from 20 to 400 Pa.According to the combined global efficiency,R×f_(+1),P_(0)=240 Pa is obtained as the optimum pressure for the maximum global efficiency in the incident energy range investigated.
基金Supported by Beijing Training Project for the Leading Talents in S&T(Z171100001117158)
文摘A test strip was developed to rapidly detect fluoroquinolones in foods by colloidal gold immunochromatography method in combination with a food safety analyzer. The results showed that the test strip has the detection sensitivity of 20 μg/L for enrofloxacin, sarafloxacin, difloxacin, ofloxacin, norfloxacin, ciprofloxacin, pefloxacin, flumequine and danofloxacin, and the detection sensitivity of 40 μg/L for enoxacin and oxolinic acid. The test strip consumes only 10 min for detection, and the false positive rate and the false negative rate are both zero. The test strip can accurately, reliably and easily detect residual fluoroquinolones in foods, and is suitable for on-site detection of a large number of samples.
