The bottom ash and fly ash from the co-combustion of wood residues and peat at a bubbling fluidised bed boiler（296 MW） contained only quartz（SiO_2）, microcline（KAl Si_3O_8） and albite（NaAlSi_3O_8）. Thus, X-ray...The bottom ash and fly ash from the co-combustion of wood residues and peat at a bubbling fluidised bed boiler（296 MW） contained only quartz（SiO_2）, microcline（KAl Si_3O_8） and albite（NaAlSi_3O_8）. Thus, X-ray powder diffraction（XRD） was not useful for clarifying the difference in the release of associated heavy metals from ash matrices. In order to assess the release of heavy metals from ashes under changing environmental conditions, they were sequentially extracted and fractionated by the BCR-procedure into acid soluble/exchangeable（CH_3COOH）, reducible（NH_2OH-HCl） and oxidizable（H_2O_2/CH_3COONH_4） phases. The CH_3 COOH extractable fraction in conjunction with the total heavy metals concentrations were used to calculate the risk assessment code values for heavy metals leaching from the ash matrix. The leaching studies indicate that the heavy metals in the bottom ash and fly ash are bound to different fractions with different strengths. From the environmental and utilization perspectives, heavy metals in ashes posed different levels of environmental contamination risk. Only As in the bottom ash posed a very high risk. High risk metals were Cd in the bottom ash as well as As, Cd and Se in the fly ash.展开更多
The prediction of nuclear cross-section data is crucial, especially in the absence of experimental data or in the difficulty of these experimental data. Nickel(Ni) is an important material in fusion and fission reacto...The prediction of nuclear cross-section data is crucial, especially in the absence of experimental data or in the difficulty of these experimental data. Nickel(Ni) is an important material in fusion and fission reactor technologies, the production of radionuclides in nuclear medicine,and many other fields. In this study, the excitation functions for^(60,62) Ni(a,n),^(60,61) Ni(a,2 n),^(58,64) Ni(a,p), and ^(nat)Ni(a,x) reactions have been investigated by using preequilibrium reaction models. The calculations of the excitation functions for the reactions are used with the geometry-dependent hybrid model in ALICE/ASH code and the two-component exciton model in TALYS 1.8 code. The obtained results are compared to each other, and the experimental data are taken from the EXFOR database.展开更多
The aim of this study was to assess Readiness of Healthcare facilities to Implement onsite Healthcare Waste Management Protocols and Incineration Guidelines in Tanzania. To address this, a national assessment was cond...The aim of this study was to assess Readiness of Healthcare facilities to Implement onsite Healthcare Waste Management Protocols and Incineration Guidelines in Tanzania. To address this, a national assessment was conducted country wide to assess readiness of Healthcare Facilities (HCFs) to undertake various Healthcare Waste Management (HCWM) initiatives with particular focus to adherence to HCWM protocols and incineration guidelines. The assessment of healthcare waste management was conducted in facilities in the 26 regions of Tanzania mainland for one month. A standardized checklist and tools were used to assess and monitor various aspects related to healthcare waste management using open source software for data collection (ODK). Data were analyzed using SPSS computer software. It was observed that 46.2%, 33.3% and 25% of the health centres, district hospitals and regional hospitals did not have appointed supervisors, which makes it difficult for the HCFs to perform better in managing healthcare waste in their respective facilities. It was further revealed that healthcare facilities have made remarkable improvement in the overall healthcare waste management with evidence of ongoing common activity on purchasing injection safety boxes (69.2%) and purchasing of waste bins (53.8%) at all levels. On average, about 70% of the HCFs have plans and budget though inadequate to support HCWM activities. In a conclusion Healthcare Facilities must designate a better system to compressively address healthcare waste management issues. Again the findings provide evidence for those engaged in improving HCF conditions to develop evidence-based policies and efficient programs, enhance service delivery systems, and make better use of available resources.展开更多
Auger electron emitting radionuclides have potential for the therapy of small-size cancers because of their high level of cytotoxicity, low-energy, high linear energy transfer, and short range biologic effectiveness. ...Auger electron emitting radionuclides have potential for the therapy of small-size cancers because of their high level of cytotoxicity, low-energy, high linear energy transfer, and short range biologic effectiveness. Auger emitter 165Er (T1/2 = 10.3 h, IEC = 100%) is a potent nuclide for targeted radionuclide therapy. 165Er excitation function via 165Ho(p,n)165Er, 165Ho(d,2n)165Er, 166Er(p,2n)165Tm→165Er, 166Er(d,3n)165Tm→165Er, natEr(p,xn)165Tm→165Er and 164Er(d,n)165Tm→165Er reactions were calculated by ALICE/91, ALICE/ASH (GDH Model & Hybrid Model) and TALYS-1.2 (Equilibrium & Pre-Equilibrium) codes and compared to existing data. Requisite for optimal thicknesses of targets were obtained by SRIM code for each reaction.展开更多
This presented study is to make comparison of cross sections to produce 117Sb and 90Nb via different reactions with particle incident energy up to 70 MeV as a part of systematic studies on particle-induced activations...This presented study is to make comparison of cross sections to produce 117Sb and 90Nb via different reactions with particle incident energy up to 70 MeV as a part of systematic studies on particle-induced activations on enriched Sn, Y2O3 and ZrO2 targets, theoretical calculation of production yield, calculation of required thickness of target and suggestion of optimum reaction to produce Antimony-117 and Niobium-90.展开更多
文摘The bottom ash and fly ash from the co-combustion of wood residues and peat at a bubbling fluidised bed boiler（296 MW） contained only quartz（SiO_2）, microcline（KAl Si_3O_8） and albite（NaAlSi_3O_8）. Thus, X-ray powder diffraction（XRD） was not useful for clarifying the difference in the release of associated heavy metals from ash matrices. In order to assess the release of heavy metals from ashes under changing environmental conditions, they were sequentially extracted and fractionated by the BCR-procedure into acid soluble/exchangeable（CH_3COOH）, reducible（NH_2OH-HCl） and oxidizable（H_2O_2/CH_3COONH_4） phases. The CH_3 COOH extractable fraction in conjunction with the total heavy metals concentrations were used to calculate the risk assessment code values for heavy metals leaching from the ash matrix. The leaching studies indicate that the heavy metals in the bottom ash and fly ash are bound to different fractions with different strengths. From the environmental and utilization perspectives, heavy metals in ashes posed different levels of environmental contamination risk. Only As in the bottom ash posed a very high risk. High risk metals were Cd in the bottom ash as well as As, Cd and Se in the fly ash.
文摘The prediction of nuclear cross-section data is crucial, especially in the absence of experimental data or in the difficulty of these experimental data. Nickel(Ni) is an important material in fusion and fission reactor technologies, the production of radionuclides in nuclear medicine,and many other fields. In this study, the excitation functions for^(60,62) Ni(a,n),^(60,61) Ni(a,2 n),^(58,64) Ni(a,p), and ^(nat)Ni(a,x) reactions have been investigated by using preequilibrium reaction models. The calculations of the excitation functions for the reactions are used with the geometry-dependent hybrid model in ALICE/ASH code and the two-component exciton model in TALYS 1.8 code. The obtained results are compared to each other, and the experimental data are taken from the EXFOR database.
文摘The aim of this study was to assess Readiness of Healthcare facilities to Implement onsite Healthcare Waste Management Protocols and Incineration Guidelines in Tanzania. To address this, a national assessment was conducted country wide to assess readiness of Healthcare Facilities (HCFs) to undertake various Healthcare Waste Management (HCWM) initiatives with particular focus to adherence to HCWM protocols and incineration guidelines. The assessment of healthcare waste management was conducted in facilities in the 26 regions of Tanzania mainland for one month. A standardized checklist and tools were used to assess and monitor various aspects related to healthcare waste management using open source software for data collection (ODK). Data were analyzed using SPSS computer software. It was observed that 46.2%, 33.3% and 25% of the health centres, district hospitals and regional hospitals did not have appointed supervisors, which makes it difficult for the HCFs to perform better in managing healthcare waste in their respective facilities. It was further revealed that healthcare facilities have made remarkable improvement in the overall healthcare waste management with evidence of ongoing common activity on purchasing injection safety boxes (69.2%) and purchasing of waste bins (53.8%) at all levels. On average, about 70% of the HCFs have plans and budget though inadequate to support HCWM activities. In a conclusion Healthcare Facilities must designate a better system to compressively address healthcare waste management issues. Again the findings provide evidence for those engaged in improving HCF conditions to develop evidence-based policies and efficient programs, enhance service delivery systems, and make better use of available resources.
文摘Auger electron emitting radionuclides have potential for the therapy of small-size cancers because of their high level of cytotoxicity, low-energy, high linear energy transfer, and short range biologic effectiveness. Auger emitter 165Er (T1/2 = 10.3 h, IEC = 100%) is a potent nuclide for targeted radionuclide therapy. 165Er excitation function via 165Ho(p,n)165Er, 165Ho(d,2n)165Er, 166Er(p,2n)165Tm→165Er, 166Er(d,3n)165Tm→165Er, natEr(p,xn)165Tm→165Er and 164Er(d,n)165Tm→165Er reactions were calculated by ALICE/91, ALICE/ASH (GDH Model & Hybrid Model) and TALYS-1.2 (Equilibrium & Pre-Equilibrium) codes and compared to existing data. Requisite for optimal thicknesses of targets were obtained by SRIM code for each reaction.
文摘This presented study is to make comparison of cross sections to produce 117Sb and 90Nb via different reactions with particle incident energy up to 70 MeV as a part of systematic studies on particle-induced activations on enriched Sn, Y2O3 and ZrO2 targets, theoretical calculation of production yield, calculation of required thickness of target and suggestion of optimum reaction to produce Antimony-117 and Niobium-90.
