eon
eon 1. The largest
geologic-time unit, incorporating a number of
eras. The equivalent
chronostratigraphic unit is the
eonothem. Originally, two eons were proposed in 1930 by G. H. Chadwick. The younger was the
Phanerozoic Eon (time of evident life), comprising the
Cenozoic,
Mesozoic, and
Palaeozoic Eras, and this term is still used. The term suggested for the preceding eon was the
Cryptozoic (time of hidden life). This time has also been called the
Archaeozoic (time of most ancient life), but most commonly has been known simply as the
Precambrian. Three eons have been proposed for Precambrian time: the Priscoan for time before 4000 Ma ago; the
Archaean for 4000–2500 Ma ago; and the
Proterozoic for 2500–590 Ma ago; the term ‘Precambrian’ is still in frequent use but is
informal.
2. A time unit of 10
9 present Earth years.
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Effect of Flower Color and Sampling Time on Volatile Emanation in Alfalfa Flowers.(Statistical Data Included)
Magazine article from: Crop Science; 1/1/2000; ; 700+ words
; ...quality seed (Viands et al., 1988). Emanation of flower volatiles in this species has...species to determine whether volatile emanation of flowers could be affected by their...Dobson, 1994). Daily rhythms of emanation were also observed in alfalfa flowers...
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An Emanation in search of a Penumbra
Magazine article from: Human Events; 7/23/1999; ; 700+ words
; ...abortion is derived from "penumbras and emanations" and there's no Penumbras and Emanations Clause either. Not only does the emperor...support for the nonexistent Penumbras and Emanations Clause-and even other novel constitutional...
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Recycled polyols from scrap flexible foams and their use for low-emanation foam: in this paper, presented at UTECH Europe 2009 in Maastricht, 31 Mar-2 April, progress in the work of an industry consortium on recycling flexible foam by acidolysis is described. Evaluation of novel fire retardants for low-emanation foams is also discussed.(acidolysis)
Magazine article from: Urethanes Technology International; 6/1/2009; ; 700+ words
; ...meet requirements for low-emanation flexible foams. Creation...effectiveness and examined for their emanation properties in flexible foams...concerns regarding toxicity and emanations with such materials. Generally...produced, although their emanation profile is better than that...
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Laboratory Simulations of Groundwater Depth Changes and Soil Radon Emanation
Magazine article from: Soil & Sediment Contamination; 1/1/2004; ; 372 words
; RADIONUCLIDES Measurements of radon emanation in soil gas exhibit changes related to...water table causes an increase in radon emanation while a falling water table causes a...at relatively high levels, the radon emanation slowly deceases while if the water table...
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Cryptek Continues to Expand TEMPEST Offerings With Acquisition of EMCON Emanation Control Limited.
PR Newswire; 3/14/2007; 700+ words
; ...its capabilities as it acquires EMCON Emanation Control Limited, a Canadian-based...announced today that it has acquired EMCON Emanation Control Limited, a Canadian-based...and solutions to suppress compromising emanations. EMCON is the largest TEMPEST products...
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Emanation and return: archive as liberator.
Magazine article from: Afterimage; 11/1/2007; ; 700+ words
; ...The photographs become revelations of the soul, literally "emanations of the referent" that touch us through their "carnal medium...project provides a protected park within which the photographic emanations might be safe. [ILLUSTRATION OMITTED] According to Roland...
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`Privacy, Penumbra and Emanations'
Newspaper article from: The Washington Post; 12/20/1992; 482 words
; ...almost a shadow") formed, he said, by unspecified "emanations" from the Bill of Rights. Justice Douglas then placed within...decisions. How this mysterious trinity of privacy, penumbra and emanations had eluded legal scholars for the then 176 years of our constitutional...
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Plotinus's metaphysics: emanation or creation?
Magazine article from: The Review of Metaphysics; 3/1/1993; ; 700+ words
; ...It is somewhat less common to find analyses of the term "emanation" so used. In this paper I shall be concerned solely with...it would seem just incorrect to construe the metaphors of emanation in a manner which would make Plotinus contradict that axiom...
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The budget, TEMPEST, and common sense. (defense budget; Transient Electromagnetic Pulse Emanations Standard)(Department of Defense requirements for contractors)
Magazine article from: Security Management; 5/1/1991; ; 700+ words
; ...Department of Defense (DoD), Transient Electromagnetic Pulse Emanations Standard (TEMPEST) requirements levied on DoD contracts...of DoD Directive C-5200.19, "Control of Compromising Emanations (U)," on February 23, 1990. This document applied the...
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Emanation reduction using novel, non-fugitive additives for flexible PU foams.(polyurethanes)
Magazine article from: Urethanes Technology; 12/1/2005; ; 700+ words
; ...manufacturers for additives that are not going to be released into the environment. Stringent requirements regarding the emanations of volatile organic compounds (VOC's) from the polyurethane article are already standard in numerous industrial applications...
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Emanations
Encyclopedia entry from: Encyclopedia of Occultism and Parapsychology
Emanations Supposedly perceived by...by mainstream science, emanations play a significant part...seem to be, have their emanations and their poles, living...in motion. The idea of emanation and magnetism is also found...
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emanation
Book article from: The Columbia Encyclopedia, Sixth Edition
emanation [Lat...radiations, or emanations, originating...the belief in emanation denies that...emergence through emanations. From God...stone fell are emanations, becoming...and fainter. Emanation never ceases...
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Emanation(s)
Book article from: The Concise Oxford Dictionary of World Religions
Emanation(s). Expressions of power...contingent) appearance. Emanations are characteristically gnostic...Tibetan religion ), an emanation expresses either the profound...said to be an ‘emanation’ of the bodhisattva...
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Jerusalem: The Emanation of the Giant Albion
Book article from: The Concise Oxford Companion to English Literature
Jerusalem: The Emanation of the Giant Albion, a prophetic poem by Blake , written and etched...beyond the Vegetable Universe, and to reunion with his banished emanation, the lovely Jerusalem. Blake mingles prophecy with social criticism...
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emanations
Book article from: A Dictionary of the Internet
emanations Radiation which is produced by devices that are attached to a network. Typically they are produced by monitors or other visual...
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