In this paper, we have investigated the temperature dependence of the ultrasonic parameters like ultrasonic velocities and Grüneisen parameters in californium monopnictides CfY (Y: N, As and Sb) for longitudinal ...In this paper, we have investigated the temperature dependence of the ultrasonic parameters like ultrasonic velocities and Grüneisen parameters in californium monopnictides CfY (Y: N, As and Sb) for longitudinal and shear waves along , and crystallographic directions in the temperature range 100–500K. For the same evaluation the second- and third- order elastic constants have also been computed for these monopnictides using Coulomb and Born-Mayer potential upto second nearest neighborhood. The mechanical properties and stability of CfN is best, because of its high valued elastic constants. Ultrasonic velocity is found to be highest for CfAs along all chosen directions, so CfAs will be most suitable compound for wave propagation. The obtained results of present investigation are discussed in along with identified thermophysical properties.展开更多
A new composite of silicone rubber and boric acid was developed to be used as a personal wearing for protection from nuclear radiation. The capability of this material for absorbing thermal neutrons of different inten...A new composite of silicone rubber and boric acid was developed to be used as a personal wearing for protection from nuclear radiation. The capability of this material for absorbing thermal neutrons of different intensities followed by a detonation of nuclear weapon has been investigated. This investigation was performed by using californium-252 neutron source of like fission spectrum. The thermal neutron flux was measured behind different thicknesses of the developed material using a BF3 detector. Two positions of measurements were performed;at position near the detonation where the intensity of thermal neutron flux is low and at position far from the detonation where the intensity of thermal neutron is high. For both cases, the contribution of total thermal, initial incident and new produced thermal neutron fluxes are measured. The obtained results indicated that, addition of boron with concentration of about 17% to the silicon rubber tends to decrease the flux by more than 70%.展开更多
Background:Cervical cancer is the sixth most common cancer in Chinese women.A standard treatment modal?ity for cervical cancer is the combination of surgery,chemotherapy,external?beam radiotherapy and intracavitary br...Background:Cervical cancer is the sixth most common cancer in Chinese women.A standard treatment modal?ity for cervical cancer is the combination of surgery,chemotherapy,external?beam radiotherapy and intracavitary brachytherapy.The aim of this study was to retrospectively assess the long?term treatment outcomes of patients with cervical cancer who were treated with californium?252 neutron brachytherapy combined with external?beam radio?therapy plus concurrent chemotherapy.Methods:We retrospectively analyzed the medical records of 150 patients with primary stages IB?IVB cervical cancer who received neutron brachytherapy combined with external?beam radiotherapy concurrently with cisplatin chemo?therapy.All patients were followed up.Using an actuarial analysis,patient outcomes and treatment?related adverse effects were evaluated and compared.Results:The median overall survival(OS)was 33.2 months.The 3?year progression?free survival rates for patients with stages I–II,III,and IV diseases were 81.0%(68/84),65.0%(39/60),and 0%(0/6),respectively;the 3?year OS rates were 90.5%(76/84),85.0%(51/60),and 16.7%(1/6),respectively.Vaginal bleeding was controlled within the median time of4.0 days.One month after treatment,97.3%of patients achieved short?term local control.The local recurrence rates for patients with stages I–II,III,and IV disease were 4.8%(4/84),11.7%(7/60),and 33.3%(2/6),respectively,and the occurrence rates of distant metastasis were 16.7%(14/84),25.0%(15/60),and 100.0%(6/6),respectively.Cancer stage,tumor size,and lymph node metastasis were identified as prognostic risk factors,but only lymph node metastasis was found to be an independent prognostic factor.The most common adverse effects during treatment were grades 1 and 2 irradiation?related proctitis and radiocystitis.Conclusion:For patients with cervical cancer,neutron brachytherapy combined with external?beam radiotherapy plus concurrent chemotherapy produces a rapid response and greatly improves local control and long?term survival rates with toler展开更多
文摘In this paper, we have investigated the temperature dependence of the ultrasonic parameters like ultrasonic velocities and Grüneisen parameters in californium monopnictides CfY (Y: N, As and Sb) for longitudinal and shear waves along , and crystallographic directions in the temperature range 100–500K. For the same evaluation the second- and third- order elastic constants have also been computed for these monopnictides using Coulomb and Born-Mayer potential upto second nearest neighborhood. The mechanical properties and stability of CfN is best, because of its high valued elastic constants. Ultrasonic velocity is found to be highest for CfAs along all chosen directions, so CfAs will be most suitable compound for wave propagation. The obtained results of present investigation are discussed in along with identified thermophysical properties.
文摘A new composite of silicone rubber and boric acid was developed to be used as a personal wearing for protection from nuclear radiation. The capability of this material for absorbing thermal neutrons of different intensities followed by a detonation of nuclear weapon has been investigated. This investigation was performed by using californium-252 neutron source of like fission spectrum. The thermal neutron flux was measured behind different thicknesses of the developed material using a BF3 detector. Two positions of measurements were performed;at position near the detonation where the intensity of thermal neutron flux is low and at position far from the detonation where the intensity of thermal neutron is high. For both cases, the contribution of total thermal, initial incident and new produced thermal neutron fluxes are measured. The obtained results indicated that, addition of boron with concentration of about 17% to the silicon rubber tends to decrease the flux by more than 70%.
文摘Background:Cervical cancer is the sixth most common cancer in Chinese women.A standard treatment modal?ity for cervical cancer is the combination of surgery,chemotherapy,external?beam radiotherapy and intracavitary brachytherapy.The aim of this study was to retrospectively assess the long?term treatment outcomes of patients with cervical cancer who were treated with californium?252 neutron brachytherapy combined with external?beam radio?therapy plus concurrent chemotherapy.Methods:We retrospectively analyzed the medical records of 150 patients with primary stages IB?IVB cervical cancer who received neutron brachytherapy combined with external?beam radiotherapy concurrently with cisplatin chemo?therapy.All patients were followed up.Using an actuarial analysis,patient outcomes and treatment?related adverse effects were evaluated and compared.Results:The median overall survival(OS)was 33.2 months.The 3?year progression?free survival rates for patients with stages I–II,III,and IV diseases were 81.0%(68/84),65.0%(39/60),and 0%(0/6),respectively;the 3?year OS rates were 90.5%(76/84),85.0%(51/60),and 16.7%(1/6),respectively.Vaginal bleeding was controlled within the median time of4.0 days.One month after treatment,97.3%of patients achieved short?term local control.The local recurrence rates for patients with stages I–II,III,and IV disease were 4.8%(4/84),11.7%(7/60),and 33.3%(2/6),respectively,and the occurrence rates of distant metastasis were 16.7%(14/84),25.0%(15/60),and 100.0%(6/6),respectively.Cancer stage,tumor size,and lymph node metastasis were identified as prognostic risk factors,but only lymph node metastasis was found to be an independent prognostic factor.The most common adverse effects during treatment were grades 1 and 2 irradiation?related proctitis and radiocystitis.Conclusion:For patients with cervical cancer,neutron brachytherapy combined with external?beam radiotherapy plus concurrent chemotherapy produces a rapid response and greatly improves local control and long?term survival rates with toler
