Earth unique factors

The Earth is a highly unusual planet because life did evolve on it and it thrived to the extent that the surface and atmosphere of the planet were greatly modified. The Earth is unique in this respect relative to all known astronomical bodies (Taylor, 1999). The Earth s location, composition, and evolutionary history are all significant factors in the planet s success in nurturing life. Critical factors include its temperature, its atmosphere, its oceans, its long-term stability and its "just right" abundance of water and other light element compounds. 

Water. Water generally occurs in air in low or relatively low concentrations, mostly in the form of atmospheric moisture. Its importance cannot, however, be overemphasized, since atmospheric moisture, unique to the surface of the earth, is a determining factor in the water cycle (see below) and in living and other processes. Moisture is, therefore, one of the most important and probably the most relevant atmospheric components for the majority of living processes. 

It is intriguing that Mo is an important element in biology despite its scarcity at the Earth s surface—indeed, no element of similar scarcity is so biochemically ubiquitous. The reason for this paradoxical combination is unknown. Possible explanations include the unique chemical character of this element, evolutionary adaptation to the abrmdance of Mo in oxygenated oceans relative to other transition metals, a legacy of prebiotic chemical evolution in Mo-rich environments (e.g., in association with sulfide minerals), or some combination of these factors. Regardless, this paradox has inspired creative hypotheses about the importance of Mo in evolution (Crick and Orgel 1973 Anbar and Knoll 2002). 

These results suggest that oxidation state is not solely responsible for catalyst deactivation but that other factors such as V location and mobility may play an important role. Basic alkaline earth oxide passivators such as MgO, admixed to the catalyst, interact strongly with vanadium during the regeneration period. Although the oxidation state of vanadium is essentially unaffected, MgO structurally modifies V as evidenced by a unique X-ray absorption spectrum. 

The discovery of the ability of AB5 compounds (A = rare earth, B = transition metal) to form hydrides with unique properties stimulated research and development in several areas (J, 2, 3, 4). Although the physicochemical properties of some AB5 hydrides were measured, the factors that determine the hydrogen dissociation pressures of these materials are not completely understood. 

Our background with chelate complexes suggested the use of Group IA and IIA metal salts for selective polyamine complexation. The specificity of the interaction between alkali-metal and alkaline-earth salts and certain polyamines provides a sensitive technique for separating single polyamines from multicomponent samples. These separations, the factors that affect complex formation, and the unique properties of the poly-tertiary amine chelates of inorganic lithium compounds are discussed in this paper. 

Uniquely in the history of our planet, all these factors — the carbon isotopes, sulphur isotopes, strontium isotopes and rare-earth elements — simultaneously point to a rise in free oxygen. Indeed, the wild swings in environmental conditions during the 160-million-year snowball Earth period may have pushed atmospheric oxygen up to nearly modern levels. At the same time, however, there was a re-emergence of banded-iron... 

Cattell s trait theory is taken as an example of a descriptive theory. From extensive research based upon the responses to questionnaires on their beliefs and preferences by many thousands of individuals, Cattell has produced a list of 16 personality factors (see Table 13.2). The factors are envisaged as 16 dimensions on which an individual s position can be plotted to produce a profile which describes that unique individual. Since someone can score from 1 to 10 on each scale, these 16 scales provide 1 unique character combinations or personalities, which is more than the total number of human beings who have ever walked the earth since Homo sapiens evolved. 

The chemistry and biology of Earth s vast oceans are unique because of their high salt content, their great depth, and other factors. Oceanographic chemistry is a discipline in its own right. The environmental problems of the oceans have increased greatly in recent years because of the release of pollutants to oceans, oil spills, and increased utilization of natural resources from oceans. 

The potential of the 2 17 compounds is sufficiently high to justify more effort in the near future in order to develop permanent magnets with unique properties and new record values in excess of 30MGOe. This value is three times the record value of Alnico magnets which were the best magnets ten years ago. For some applications, however, rare earth-transition metal permanent magnets are superior compared to older magnets by a factor of ten or even more. 

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