Fast neutron activation of nitrogen and oxygen contained in the explosives used for simulated mine samples has been preliminarily carried out in our laboratory. By spectroscopic analysis of characteristic γ-rays emit...Fast neutron activation of nitrogen and oxygen contained in the explosives used for simulated mine samples has been preliminarily carried out in our laboratory. By spectroscopic analysis of characteristic γ-rays emitted from activated nitrogen and oxygen, mine can be identified almost instantly. This technique integrated with robottes would be a method for mine scavenging.展开更多
Islamic silver coins (Dirhams) running the period between 107 to 126 Hijri( (726-743 AD), which belong to the Umayyad Empire period, 41-132 hijri (661-750 AD), were selected for analysis by using instrumental neutron ...Islamic silver coins (Dirhams) running the period between 107 to 126 Hijri( (726-743 AD), which belong to the Umayyad Empire period, 41-132 hijri (661-750 AD), were selected for analysis by using instrumental neutron activation analysis techniques. During this period (105-126H), (724-743AD), the Caliph Hisham Eben Abdlemalek ruled the Umayyad Empire. Dirhams were irradiated in a reactor neutron activation facility. Levels of various elements viz. Cu, Ag and Au were estimated. It was found that the average silver concentration, the base constituent of the Dirham, was about 88 wt%. Correlation between the composition of Dirhams and the historical implications was discussed.展开更多
Analysis of rain-and fresh water for trace constituents is it manda- tory part of environmental monitoring. This text gives a survey of neutron activation analysis (NAA) within the framework of current environmental w...Analysis of rain-and fresh water for trace constituents is it manda- tory part of environmental monitoring. This text gives a survey of neutron activation analysis (NAA) within the framework of current environmental water research pro- grammes, based on the practice developed in co-operation with the Dutch Energy Research Centre at Petten (ECN). While the procedures reported in literature cover about thirty five elements, our routine procedures of instrumental neutron activation analysis (INAA) is limited to ten to fifteen elements. The use of some dedicated ra- diochemical separations (RNAA) adds another six, some of which are speciatcd as well. Current contributions of NAA to water analysis center on determination and speciation of anionic trace elements, notably Br, I, As, and Se, on the assay of some ultra traces like Ag, Au and Hg and on validation.展开更多
The effects of berbamine, an alkaloid of dibenzylisoquinoline, on PAF produc tion in human neutrophils and on platelet aggregation induced by PAF were studied and compared with those of the calcium antagonist verapam...The effects of berbamine, an alkaloid of dibenzylisoquinoline, on PAF produc tion in human neutrophils and on platelet aggregation induced by PAF were studied and compared with those of the calcium antagonist verapamil. Preincubation with berbamine (50 mmol / L, 100 mmol / L) or verapamil (10 mmol / L, 100 mmol / L) was shown to significantly inhibit A 23187 stimulated PAF synthesis. Berbamine and verapamil were found to inhibit platelet aggregation induced by PAF 70 pmol / L in a dose dependent manner. These results suggest that the inhibitory effects of berbamine and verapamil on A 23187 stimulated PAF synthesis in human neutrophils and PAF induced platelet aggregation are possibly brought about by inhibiting cellular calcium influx.展开更多
A combination of NAA and micro-PIXE was used to study concentrations and distributions of platinum group elements (PGE) in ores from Xinjie Cu-Pt deposit.The NAA results of the bulk indicate that the ores belong to th...A combination of NAA and micro-PIXE was used to study concentrations and distributions of platinum group elements (PGE) in ores from Xinjie Cu-Pt deposit.The NAA results of the bulk indicate that the ores belong to the enriched Pt-Pd type.The element concentration maps of scanning micro-PIXE for the ores show that the occurence form of Pt is independent arsenide minerals. No PGE were detected in chalcopyrite of Xinjie Cu-Pt deposit. These information are economically beneficial to the mineral smelting process.展开更多
The contents of total and methyl mercury in scalp hair samples of 1179 fishermenliving at a typical Hg-polluted region in Northeast China and 27 lying-in womenand their new born babies in Beijing have been determined ...The contents of total and methyl mercury in scalp hair samples of 1179 fishermenliving at a typical Hg-polluted region in Northeast China and 27 lying-in womenand their new born babies in Beijing have been determined by illstrumental neutronactivation analysis, gas chromatography (electron coupling) and other techniqlles.Only 18 of all fishermen have the Hg contents above 5 ig/g, which indicates that theHg pollution there has been substantially alleviated. The longitudinal Hg patternsof the lying-in women show a gradually lowering tendency during pregnant period.Further, the Hg contents of the new-born babies are generally above or close to those oftheir mothers, confirming the mechanism that the methyl Hg, an organic species of Hgwith high toxicity, is readily able to penetrate the placental barrier and accumulatedin fetus. Thus, the mercury poison hajs occurred at the early stage of pregnancy.展开更多
Twenty five impurity elements in aluminium applied as reactor material are determined. Titanium and nickel are determined with epithermal neutron activation analysis (NAA), magnesium and silicon by inductance coupling...Twenty five impurity elements in aluminium applied as reactor material are determined. Titanium and nickel are determined with epithermal neutron activation analysis (NAA), magnesium and silicon by inductance coupling plasma emission spectra (ICP), other elements by thermal NAA. The fission coefficient of uraniumis given by an experiment, the interferences of uranium to Ce, Nd, Mo, Zr, La, Sin are subtracted. The detection limits of these methods to all of impurity elements in aluminium are calculated.展开更多
文摘Fast neutron activation of nitrogen and oxygen contained in the explosives used for simulated mine samples has been preliminarily carried out in our laboratory. By spectroscopic analysis of characteristic γ-rays emitted from activated nitrogen and oxygen, mine can be identified almost instantly. This technique integrated with robottes would be a method for mine scavenging.
文摘Islamic silver coins (Dirhams) running the period between 107 to 126 Hijri( (726-743 AD), which belong to the Umayyad Empire period, 41-132 hijri (661-750 AD), were selected for analysis by using instrumental neutron activation analysis techniques. During this period (105-126H), (724-743AD), the Caliph Hisham Eben Abdlemalek ruled the Umayyad Empire. Dirhams were irradiated in a reactor neutron activation facility. Levels of various elements viz. Cu, Ag and Au were estimated. It was found that the average silver concentration, the base constituent of the Dirham, was about 88 wt%. Correlation between the composition of Dirhams and the historical implications was discussed.
文摘Analysis of rain-and fresh water for trace constituents is it manda- tory part of environmental monitoring. This text gives a survey of neutron activation analysis (NAA) within the framework of current environmental water research pro- grammes, based on the practice developed in co-operation with the Dutch Energy Research Centre at Petten (ECN). While the procedures reported in literature cover about thirty five elements, our routine procedures of instrumental neutron activation analysis (INAA) is limited to ten to fifteen elements. The use of some dedicated ra- diochemical separations (RNAA) adds another six, some of which are speciatcd as well. Current contributions of NAA to water analysis center on determination and speciation of anionic trace elements, notably Br, I, As, and Se, on the assay of some ultra traces like Ag, Au and Hg and on validation.
文摘The effects of berbamine, an alkaloid of dibenzylisoquinoline, on PAF produc tion in human neutrophils and on platelet aggregation induced by PAF were studied and compared with those of the calcium antagonist verapamil. Preincubation with berbamine (50 mmol / L, 100 mmol / L) or verapamil (10 mmol / L, 100 mmol / L) was shown to significantly inhibit A 23187 stimulated PAF synthesis. Berbamine and verapamil were found to inhibit platelet aggregation induced by PAF 70 pmol / L in a dose dependent manner. These results suggest that the inhibitory effects of berbamine and verapamil on A 23187 stimulated PAF synthesis in human neutrophils and PAF induced platelet aggregation are possibly brought about by inhibiting cellular calcium influx.
文摘A combination of NAA and micro-PIXE was used to study concentrations and distributions of platinum group elements (PGE) in ores from Xinjie Cu-Pt deposit.The NAA results of the bulk indicate that the ores belong to the enriched Pt-Pd type.The element concentration maps of scanning micro-PIXE for the ores show that the occurence form of Pt is independent arsenide minerals. No PGE were detected in chalcopyrite of Xinjie Cu-Pt deposit. These information are economically beneficial to the mineral smelting process.
文摘The contents of total and methyl mercury in scalp hair samples of 1179 fishermenliving at a typical Hg-polluted region in Northeast China and 27 lying-in womenand their new born babies in Beijing have been determined by illstrumental neutronactivation analysis, gas chromatography (electron coupling) and other techniqlles.Only 18 of all fishermen have the Hg contents above 5 ig/g, which indicates that theHg pollution there has been substantially alleviated. The longitudinal Hg patternsof the lying-in women show a gradually lowering tendency during pregnant period.Further, the Hg contents of the new-born babies are generally above or close to those oftheir mothers, confirming the mechanism that the methyl Hg, an organic species of Hgwith high toxicity, is readily able to penetrate the placental barrier and accumulatedin fetus. Thus, the mercury poison hajs occurred at the early stage of pregnancy.
文摘Twenty five impurity elements in aluminium applied as reactor material are determined. Titanium and nickel are determined with epithermal neutron activation analysis (NAA), magnesium and silicon by inductance coupling plasma emission spectra (ICP), other elements by thermal NAA. The fission coefficient of uraniumis given by an experiment, the interferences of uranium to Ce, Nd, Mo, Zr, La, Sin are subtracted. The detection limits of these methods to all of impurity elements in aluminium are calculated.
