منابع مشابه
Grasses
over one’s genes? Perhaps it is because this notion resonates with a public that in the eighties and nineties the same press have bullied into believing that there is ‘a gene for everything’. In that sense, the debate is remarkably similar to the one on whether we humans (or animals in general) have such a thing as a free — or conscious — will. Much like with the idea of the vulgarised genetic ...
متن کاملIsotope Geochemistry
Isotopic analysis can be performed on minerals, rocks, soil, tissue, gases, and liquids – just about anything. In view of the broad possibilities, we will only cover a few generalities here. In most instances, the element to be analyzed must be first isolated and purified before it can undergo isotopic analysis in a mass spectrometer. Purification is necessary to avoid isobaric interferences an...
متن کاملChapter 5 Geochemistry
One hundred and nineteen samples of clay (n = 42), rock and sand temper (n = 7), and pottery (n = 70) from the various drainages in and around the North Carolina Sandhills were analyzed by instrumental neutron activation analysis (NAA) at the University of Missouri Research Reactor Center (MURR). Here we report the analytical methods and describe some of the chemical patterns identified in the ...
متن کاملArsenic geochemistry and health.
Arsenic occurs naturally in the earth's crust and is widely distributed in the environment. Natural mineralization and activities of microorganisms enhance arsenic mobilization in the environment but human intervention has exacerbated arsenic contamination. Although arsenic is useful for industrial, agricultural, medicinal and other purposes, it exerts a toxic effect in a variety of organisms, ...
متن کاملStable Isotope Geochemistry
1. Background 2. Elements, Nuclides, and Stable Isotopes 3. The Mass Spectrometer and Isotope Ratio Measurement 4. Isotope Fractionation 5. Temperature and Fractionation 6. Stable Isotopes in the Hydrologic Cycle 7. O in Minerals and Rocks 8. C and Carbon Cycling 9. N Cycling in Watersheds 10.S and the Sulfur Cycle 11. Chlorine and Bromine Isotopes 12. Light Lithophile Elements: δLi and δB Glos...
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ژورنال
عنوان ژورنال: Science
سال: 2005
ISSN: 0036-8075,1095-9203
DOI: 10.1126/science.310.5752.1247d