Multiphase flow meters as the potential alternatives to separation and metering techniques have been in rapid development since 1980 s.Before its field operation,the instrument should be calibrated in a standard test-...Multiphase flow meters as the potential alternatives to separation and metering techniques have been in rapid development since 1980 s.Before its field operation,the instrument should be calibrated in a standard test-facility.In spite of the known medium and large scale facilities all over the world,we developed a laboratory scale instrument for component fraction measurements.It has a two-phase flow homogenizer loop with the clamp-on potential of the meters to provide a regime independent measurement.It is capable of delivering a complete homogenization by γ-ray densitometer.With an error of±5%in component fraction measurements,this instrument is appropriate for testing and calibrating other meters.展开更多
A bismuth oxide(Bi_2O_3)-dispersed carboxylated nitrile butadiene rubber(XNBR) flexible film was prepared as a flexible lead-free material for gamma ray(c-ray)attenuation.However,obtaining a uniform and stable dispers...A bismuth oxide(Bi_2O_3)-dispersed carboxylated nitrile butadiene rubber(XNBR) flexible film was prepared as a flexible lead-free material for gamma ray(c-ray)attenuation.However,obtaining a uniform and stable dispersion of Bi_2O_3 in carboxylated nitrile butadiene rubber latex(XNBRL) is a challenge due to sedimentation induced by the remarkable density differences.Here,this challenge was approached by reducing the Bi_2O-3 particle radius,increasing the viscosity of the latex,and adding a dispersant.The experimental results confirmed that Bi2 O3 was well dispersed in the XNBRL in the concentration range of 30–70 wt%.The mechanical properties demonstrated that the Bi_2O_3/XNBR flexible films had a good resistance to oil,acid,alkali,and hot air.The linear attenuation coefficients of the Bi_2O_3/XNBR flexible films obtained from the experiments were in good agreement with the calculated values.The attenuation efficiencies of the Bi_2O_3/XNBR flexible films with different thicknesses and Bi_2O_3 contents were investigated for a few different γ-ray energies.These results showed that the Bi_2O_3/XNBRflexible films have wide application prospects for low-energy γ-ray attenuation.展开更多
In this paper,mass attenuation coefficients of concrete,bricks and cement plaster,as shielding materials,are calculated at 59.5,356,662,1173,1274 and 1333 keV by using the MCNP-X(version 2.4.0) code.The numerical simu...In this paper,mass attenuation coefficients of concrete,bricks and cement plaster,as shielding materials,are calculated at 59.5,356,662,1173,1274 and 1333 keV by using the MCNP-X(version 2.4.0) code.The numerical simulation results are compared with previous Monte Carlo studies,experimental results and XCOM data.The effects of barite on mass attenuation coefficients are investigated.The mass attenuation coefficients increase with the barite content.Thus,our results agree well with experimental studies on gamma ray shielding of barite.It is flexible for the MN method to change the barite rates in material by small increments,which is experimentally difficult.Also,modeled geometry can be used for future approaches such as new designs and new structures especially in investigating new barite-containing materials to build nuclear reactors or high-energy radiation therapy facilities.展开更多
The gamma-ray mass attenuation coefficients of blood,bone,lung,eye lens,adipose,tissue,muscle,brain and skin were calculated at different energies(60,80,150,400,500,600,1000,1250,1500,and 2000 keV) by various theoreti...The gamma-ray mass attenuation coefficients of blood,bone,lung,eye lens,adipose,tissue,muscle,brain and skin were calculated at different energies(60,80,150,400,500,600,1000,1250,1500,and 2000 keV) by various theoretical methods such as FLUKA,GEANT4 Monte Carlo(MC) methods and XCOM program in this work.Calculated coefficients were also compared with the National Institute of Standards and Technology(NIST) values.Obtained results were highly in accordance with each other and NIST values.Our results showed that FLUKA was quite convenient in comparison to GEANT4 in the calculation of the mass attenuation coefficients of the used human body samples for low-energy photons(60,80,and 150 keV) when compared with the NIST values.展开更多
基金financially supported by Radiation Application Research School as a part of Nuclear Science and Technology Research Institute
文摘Multiphase flow meters as the potential alternatives to separation and metering techniques have been in rapid development since 1980 s.Before its field operation,the instrument should be calibrated in a standard test-facility.In spite of the known medium and large scale facilities all over the world,we developed a laboratory scale instrument for component fraction measurements.It has a two-phase flow homogenizer loop with the clamp-on potential of the meters to provide a regime independent measurement.It is capable of delivering a complete homogenization by γ-ray densitometer.With an error of±5%in component fraction measurements,this instrument is appropriate for testing and calibrating other meters.
基金supported by the National Natural Science Foundation of China(No.11405149)the Military Technology Extension Project(No.JMZF201601)
文摘A bismuth oxide(Bi_2O_3)-dispersed carboxylated nitrile butadiene rubber(XNBR) flexible film was prepared as a flexible lead-free material for gamma ray(c-ray)attenuation.However,obtaining a uniform and stable dispersion of Bi_2O_3 in carboxylated nitrile butadiene rubber latex(XNBRL) is a challenge due to sedimentation induced by the remarkable density differences.Here,this challenge was approached by reducing the Bi_2O-3 particle radius,increasing the viscosity of the latex,and adding a dispersant.The experimental results confirmed that Bi2 O3 was well dispersed in the XNBRL in the concentration range of 30–70 wt%.The mechanical properties demonstrated that the Bi_2O_3/XNBR flexible films had a good resistance to oil,acid,alkali,and hot air.The linear attenuation coefficients of the Bi_2O_3/XNBR flexible films obtained from the experiments were in good agreement with the calculated values.The attenuation efficiencies of the Bi_2O_3/XNBR flexible films with different thicknesses and Bi_2O_3 contents were investigated for a few different γ-ray energies.These results showed that the Bi_2O_3/XNBRflexible films have wide application prospects for low-energy γ-ray attenuation.
文摘In this paper,mass attenuation coefficients of concrete,bricks and cement plaster,as shielding materials,are calculated at 59.5,356,662,1173,1274 and 1333 keV by using the MCNP-X(version 2.4.0) code.The numerical simulation results are compared with previous Monte Carlo studies,experimental results and XCOM data.The effects of barite on mass attenuation coefficients are investigated.The mass attenuation coefficients increase with the barite content.Thus,our results agree well with experimental studies on gamma ray shielding of barite.It is flexible for the MN method to change the barite rates in material by small increments,which is experimentally difficult.Also,modeled geometry can be used for future approaches such as new designs and new structures especially in investigating new barite-containing materials to build nuclear reactors or high-energy radiation therapy facilities.
基金supported by Scientific Research 277 Project of Ege University under Project No.2014 FEN 026278 Uludag University under Project No.OUAP(F)-2012/26
文摘The gamma-ray mass attenuation coefficients of blood,bone,lung,eye lens,adipose,tissue,muscle,brain and skin were calculated at different energies(60,80,150,400,500,600,1000,1250,1500,and 2000 keV) by various theoretical methods such as FLUKA,GEANT4 Monte Carlo(MC) methods and XCOM program in this work.Calculated coefficients were also compared with the National Institute of Standards and Technology(NIST) values.Obtained results were highly in accordance with each other and NIST values.Our results showed that FLUKA was quite convenient in comparison to GEANT4 in the calculation of the mass attenuation coefficients of the used human body samples for low-energy photons(60,80,and 150 keV) when compared with the NIST values.
