相关论文: Neutron activation analysis of some Neolithic copp…
Ancient copper objects from Romanian Territories have been analyzed by neutron activation analysis. A series of elements is determined: Au, Ag, As, Co, Cr, Fe, Hg, Ni, Zn, Sb, Sc, Se, Sn. Using mathematical dendograms some classifications…
In this paper we have analyzed samples of Neolithic ceramics from Cucuteni-Scanteia - Vaslui county and Neolithic and Dacian ceramics from Magurele - Bucharest, by the method of neutron activation analysis. The following elements have been…
Ancient Dacian ceramics, from three different establishments from Romanian territory have been analyzed by neutron activation analysis. A series of elements has been determined: Ba, Eu, K, La, Mn, Na, Sc, Sm. Ba is the element that could be…
Radiochemical neutron activation analysis has been applied to investigate the microelements in gold samples with archaeological importance. Chemical separation has allowed the determination of traces of Ir, Os, Sb, Zn, Co, Fe, Ni.…
A number of medieval coins from the Brukenthal Museum, Sibiu, Romania have been analyzed by the means of three methods: gamma transmission, X-ray fluoresecence and neutron activation analysis. The values of the concentrations of the…
Aerosols deposits on filters from ten Romanian towns with different kinds and levels of industrial development have been studied. The concentration of elements with Z~16 have been measured by particle - induced X-ray emission (PIXE)…
Analytical measurements of the 28Si crystal used for the determination of the Avogadro constant are essential to prevent biased results or under-estimated uncertainties. A review of the existing data confirms the high-purity of silicon with…
Recent studies suggest that metal-poor stars enhanced in carbon but containing low levels of neutron-capture elements may have been among the first to incorporate the nucleosynthesis products of the first generation of stars. We have…
The determination of the Avogadro constant plays a key role in the redefinition of the kilogram in terms of a fundamental constant. The present experiment makes use of a silicon single-crystal highly enriched in 28Si that must have a total…
The results of analytical measurements performed with solid-sampling techniques are affected by the distribution of the analytes within the matrix. The effect becomes significant in case of determination of trace elements in small…
The neutron activation of shielding materials and the generated decay gamma radiation are well-known issues in terms of occupational exposure. Though the trace elements of shielding concretes can be dominant sources of the produced activity…
Seventeen representative samples of volcanic origin were collected from Ecuador (Pichincha Volcano), Iceland (Eyjafjallaj\"okull Volcano), India (Deccan Traps), Hawaii, Kilimanjaro, Mt. Etna, Rwanda (Virunga Mountains), and Uganda (Virunga…
New evaluations for several actinoids of the third version of China Evaluated Nuclear Data Library (CENDL-3.1) have been completed during the period between 2000 and 2005. The evaluations are for all neutron induced reactions with Uranium,…
A technique based on neutron activation has been developed for an extremely high sensitivity analysis of trace elements in organic materials. Organic materials are sealed in plastic or high purity quartz and irradiated at the HFIR and MITR.…
The Milky Way bulge is an important tracer of the early formation and chemical enrichment of the Galaxy. The abundances of different iron-peak elements in field bulge stars can give information on the nucleosynthesis processes that took…
In this work we have made an analytical investigation by neutron activation analysis and X-ray fluorescence of a number of pieces found on the two hearths and the slag layer discovered at the Old Town Hall from Sibiu, Romania and some bells…
Context. Over the past few years, the $R$-Process Alliance (RPA) has successfully carried out a search for stars that are highly enhanced in elements produced via the rapid neutron-capture ($r$-) process. In particular, the RPA has…
Detailed chemical composition studies of stars with enhanced abundances of neutron-capture elements can provide observational constraints for neutron-capture nucleosynthesis studies and clues for understanding their contribution to the…
Neutron(n)-capture elements (atomic number Z>30), which can be produced in planetary nebula (PN) progenitor stars via s-process nucleosynthesis, have been detected in nearly 100 PNe. This demonstrates that nebular spectroscopy is a…
Monte Carlo simulations using MCNP6.1 were performed to study the effect of neutron activation in Ar/CO$_{2}$ neutron detector counting gas. A general MCNP model was built and validated with simple analytical calculations. Simulations and…