Results 301 to 310 of about 596,259 (322)

Chemical enrichment by massive stars

New Astronomy Reviews, 2000
Abstract Heavy element abundances derived from high-quality ground-based and Hubble Space Telescope (HST) spectroscopic observations of low-metallicity blue compact galaxies (BCGs) with oxygen abundances 12+log O/H between 7.1 and 8.3 are discussed. None of the heavy element-to-oxygen abundance ratios studied here (C/O, N/O, Ne/O, Si/O, S/O, Ar/O, Fe/
Y.I. Izotov, T.X. Thuan
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Chemical enrichment of substandard beryllium concentrates

Transactions of the Kоla Science Centre of RAS. Series: Engineering Sciences, 2023
Global trends in the use of beryllium in the creation of high-tech products dictate the need to create beryllium production in Russia. The prerequisites for this are the availability of a raw material base and competencies in the field of technology for the production of beryllium metal and products based on it.
Valentine V. Menshikov, Valentina E. Matyasova, Ekaterina B. Solntseva   +2 more
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Enriching Chemical Space with Diversity‐Oriented Synthesis

ChemInform, 2007
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Gemma L, Thomas, Emma E, Wyatt, David R, Spring   +2 more
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Chemical Durability of Lanthanum‐Enriched Borosilicate Glass

International Journal of Applied Glass Science, 2013
The role of lanthanum in the alteration kinetics at different degrees of reaction progress was investigated at 90°C and p H  7 by complementary chemical ( SIMS ), morphological ( SAXS ), and structural (
Molières, Estelle, Angeli, Frédéric, Jollivet, Patrick, Gin, S., Charpentier, Thibault, Majérus, Odile, Barboux, Philippe, de Ligny, Dominique, Spalla, Olivier   +8 more
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Chemical enrichment in the early galaxy

Astrophysics and Space Science, 2003
New, precise abundance data for a large number of elements in a growing sample of extremely metal-poor stars are accumulating from the new 8-m telescopes. Combined with theoretical models, these results advance our understanding of the first generations of stars, whose nucleosynthesis products are fossilised in the oldest stars we see today and thus ...
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Chemical Labeling and Enrichment of Histone Glyoxal Adducts

ACS Chemical Biology, 2022
Because of their long half-lives and highly nucleophilic tails, histones are particularly susceptible to accumulating nonenzymatic covalent modifications, such as glycation. The resulting modifications can have profound effects on cellular physiology due to the regulatory role histones play in all DNA-templated processes; however, the complexity of ...
Devin M. Ray, Erin Q. Jennings, Igor Maksimovic, Xander Chai, James J. Galligan, Yael David, Qingfei Zheng   +6 more
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Chemical Enrichment of the Intra-Cluster Medium

Astrophysics and Space Science, 2003
We investigate the metal enrichment of the intra-cluster medium by using a method that combines N-Body simulations and a semi-analytic model (SAM) of galaxy formation. The cluster of galaxies is simulated in a flat, low density universe, with a numerical resolution that allows the detection of substructures in the dark matter background of the cluster.
Cora, S., White, S.
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Theoretical Consideration and Recent Progress of Chemical Enrichment Process for Uranium Enrichment

Journal of Nuclear Science and Technology, 1990
Research and development for uranium enrichment by oxidation-reduction chromatography, begun in 1972 despite the prevailing view that a chemical process would require several centuries of operation to attain fuel-grade uranium enrichment and would thus be impractical, led to the establishment of basic process technology permitting attainment of 3 ...
Maomi SEKO, Kunihiko TAKEDA, Hatsuki ONITSUKA, Tetsuya MIYAKE   +3 more
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Energy Consumption of Chemical Uranium Enrichment

Separation Science and Technology, 1987
Abstract A quantitative study of chemical separation energy for enriching uranium-235 by the redox chromatography was conducted. Isotope exchange reactions between U4+-UO2 2+ ions in the enrichment column are maintained by the redox reactions. The chemical separation energy is ultimately supplied by hydrogen and oxygen gas for regenerating redox agents.
T. Miyake, K. Takeda, H. Obanawa
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