All of these events (possibly with the exception of X-ray bursts) eject material with an abundance composition unique to the specific event and lead over time to the evolution of elemental (and isotopic) abundances in the galactic gas and their imprint on the next generation of stars. In ...
On the deuterium abundance and the importance of stellar mass loss in the interstellar and intergalactic medium At fixed metallicity, the deuterium fraction decreases slightly with decreasing redshift, due to the increased importance of mass-loss from intermediate-mass stars. We find that the evolution...
The characteristic charge on their ions is also 2+. IIA 元素被称为碱土金属元素。它们的特征离子电荷为 2+。这些金属,尤其是这一族的最后两个成员, 几乎和碱金属一样活泼。IIB 元素-锌,镉,汞不如 IIA 元素活泼,但是比相邻的 IB 的元素活泼得多。它们 的离子的特征电荷也是 2+。 With the exception ...
Distribution of Chemical Elements in Attic Dust as Reflection of Their Geogenic and Anthropogenic Sources in the Vicinity of the Copper Mine and Flotation ... The main aim of this article was to assess the atmospheric pollution with heavy metals due to copper mining Bu膷im near Radovi拧, the ...
Third, it is found not informative to leave empty spaces instead of approximate atomic weights for elements with unstable isotopes. Fourth, the term atomic weight vs the term atomic mass is discussed shortly, in agreement with the SI system of units and in contrary to the questionable IUPAC ...
in mycelial fungi. When we were both asked by the editor to provide updated reviews for our subjects, we got together and quickly decided that a joint article would be the best way to provide a comprehensive overview dealing with diverse genetic elements such as introns, plasmids or transposons...
7Editor's remark: Note that the technical term ‘cold fusion’ used here has nothing to do with the ‘cold fusion’ of the early 1990's which—after so much fuss, excitement and publicity—turned out to be a hoax after all. 8. 8See also Subsection 4.5, Chapter 4, Volume 1, on fis...
We urge further research on absorption of Cd and Pb from different dietary components and application of diet analysis to explain the complex nature of bioaccumulation of anthropogenic contaminants in the internal organs and tissues of birds and other species of animals, especially in species with a...
aSuch large accumulations of metal require concentration of elements hundreds or thousands of times above natural abundance, implying high-mass fluxes through small volumes of rock coupled with efficient precipitation 金属的这样大储积要求集中 元素数百或数以万计时期在自然丰盈之上,暗示高大量通过岩石的小...
2, the formation enthalpy behaviors of the halogens (F, Cl and Br) and noble gases (Ne, Ar, Kr and Xe) decrease with increasing mass, which is related to their high electronegativities under both ambient and high pressure. According to the Hume-Rothery rules, for substitutional solid ...