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In very small minerals, surface energy is important and diamonds are more stable than graphite because the diamond structure is more compact. The crossover in stability is at between 1 and 5 nm. At even smaller sizes, a variety of other forms of carbon such as fullerenes can be found, as well as diamond cores wrapped in fullerenes. [3]
Rubies, emeralds, and diamonds exhibit red fluorescence under long-wave UV, blue and sometimes green light; diamonds also emit light under X-ray radiation. Fluorescence in minerals is caused by a wide range of activators. In some cases, the concentration of the activator must be restricted to below a certain level, to prevent quenching of the ...
Researchers are investigating the effect of the station's near-weightless environment on the evolution, development, growth and internal processes of plants and animals. In response to some of this data, NASA wants to investigate microgravity 's effects on the growth of three-dimensional, human-like tissues, and the unusual protein crystals ...
The collision of a dwarf planet and an asteroid 4.5 billion years ago resulted in space diamonds in meteorites eventually landing on Earth.
In vitro studies exploring the dispersion of diamond nanoparticles in cells have revealed that most diamond nanoparticles exhibit fluorescence and are uniformly distributed. [21] Fluorescent nanodiamond particles can be mass produced through irradiating diamond nanocrystallites with helium ions. [ 22 ]
Theoretically, pure diamonds would be transparent and colorless. Diamonds are scientifically classed into two main types and several subtypes, according to the nature of defects present and how they affect light absorption: [8] Type I diamond has nitrogen (N) atoms as the main impurity, at a concentration of up to 1%. If the N atoms are in ...
dependence of risk on dose-rates in space related to the biology of DNA repair, cell regulation and tissue responses; predicting solar particle events (SPEs) extrapolation from experimental data to humans and between human populations; individual radiation sensitivity factors (genetic, epigenetic, dietary or "healthy worker" effects)
Diamonds with fluorescence were marked down in price. Ironically, in 1997, a seminal study by the Gemological Institute of America (GIA) concluded that, "in general, the strength of fluorescence had no widely perceptible effect on the color appearance of diamonds viewed table-down (as is typical in laboratory and trade grading).