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Earth source

Commercial mining of rare-earth reserves began ia the late 1800s. Mona2ite was the principal rare-earth source up until 1965. Thereafter bastnaesite production exceeded mona2ite production and as of 1992 bastnaesite, which is the world s principal source of rare earths, constituted 65% of world output of rare-earth minerals (see Table 5). In addition to the conventional ores, there are several other rare-earth resources having a low level of iadustrial production. [Pg.542]

Note The whole of the system is molecular machinery driven by outside sources of energy and is temperature dependent. We see the cell as a machine degrading energy from either inorganic (Earth) sources or the Sun (see Chapter 5). [Pg.182]

It should be kept in mind that commercially used rare earth sources contain small quantities of these other rare earths. [Pg.27]

Rare-Earth Sources and Ceria based Rare-Earth Minerals... [Pg.11]

Figure 1 Ionic radius (in angstrom) versus ionic charge for lithophile major and trace elements in mantle sihcates. Also shown are ranges of enrichment factors in average continental crust, using the estimate of (Rudnick and Fountain, 1995), relative to the concentrations in the primitive mantle (or hulk silicate Earth ) (source McDonough and Sun, 1995). Figure 1 Ionic radius (in angstrom) versus ionic charge for lithophile major and trace elements in mantle sihcates. Also shown are ranges of enrichment factors in average continental crust, using the estimate of (Rudnick and Fountain, 1995), relative to the concentrations in the primitive mantle (or hulk silicate Earth ) (source McDonough and Sun, 1995).
The hemispherical total absorptivity is not only a property of the absorbing surface. Rather, it depends on the spectral distribution of the incident radiation energy. This is shown by the different values of a for the mainly short-wave solar radiation, in which the absorption properties at small wavelengths are decisive, and for the incident radiation from an earthly source, for which the long-wave portion of the absorption spectrum a (X,T) is of importance. [Pg.522]

The water layer transmits short wave radiation almost completely unweakened. This does not hold for wavelengths A > 0.95 m. Here will be immeasurably small for s = 1.0m. As the sun, according to Example 5.3, mainly radiates in a region of short wavelengths, 36% of the total solar radiation penetrating the water will still pass through it to a depth of 1.0 m. In contrast, the mainly long wave radiation from earthly sources will already be completely absorbed in a water layer of around 2mm thickness [5.17]. [Pg.552]

Marc A. Levy, European Acid Rain The Power of Tote-Board Diplomacy, in Peter M. Haas, Robert O. Keohane, and Marc A. Levy, eds.. Institutions for the Earth Sources of Effective International Environmental Protection (Cambridge MIT Press, 1993), pp. 92-3. [Pg.147]

Levy, M. (1993). European acid rain The power of tote-board diplomacy. In Institutions for the Earth Sources of Effective Environmental Protection, Haas, R, Keohane, R. and Levy, M. (Eds.), MIT Press Cambridge, pp. 75-132. [Pg.172]

The atomic weights for these elements and a few others are now given as tenges due to the variability of values In natural terrestrial materials. (Atomic weights are based on the 2009 values in Pure Appl. Chem., 2011,83, 359-396 as tabulated at http ///www.ohem.qmul.ac.uk/iupac/AtWt/.) With permission. Newer tables now provide a range of Isotope abundances of some elements due to variations in Earthly sources. Other celestial bodies (e.g., Moon, Mars, asteroidal meteorites) display even more different Isotope variations, which enables MS measurements to identify the particular source of some meteorites. [Pg.706]

From an economic point of view the most important rare earth sources in the world... [Pg.471]

Rare earth carbonates have few uses as such. They are used as a rare earth source in synthesis and in the preparation of microcrystalline oxide powders (Yukinori and Fumikazu, 1978). Cerium carbonates have been suggested for use in thermochemical cycles for the production of hydrogen from water (Peterson and Onstott, 1978). [Pg.233]

Fig. 21.1 Bingham Canyon Mine - The richest hole on earth. (Source Kennecott Cooper)... Fig. 21.1 Bingham Canyon Mine - The richest hole on earth. (Source Kennecott Cooper)...
Although China is dominant in the production of separated rare earths (97%), it is not dominant in terms of rare earth deposits with extensive sources also in USA, India, Brazil, Malaysia, Africa and Australia. Australia has abimdant rare earths sources, and hence has the potential to be a major supplier. It was once a major exporter of monazite based on East Coast mineral sands, of which the tomist resort Fraser Island remains an imtouched example. In the 80s and early 90s, there were several attempts at major developments in Australia. WIM Minerals, a... [Pg.6]

Fig. 2.1 Determination of alkali and alkaline earths Source Own files... Fig. 2.1 Determination of alkali and alkaline earths Source Own files...

See other pages where Earth source is mentioned: [Pg.28]    [Pg.33]    [Pg.694]    [Pg.2]    [Pg.10]    [Pg.519]    [Pg.555]    [Pg.201]    [Pg.528]    [Pg.382]    [Pg.426]    [Pg.534]    [Pg.186]    [Pg.175]    [Pg.534]    [Pg.2]    [Pg.5]   
See also in sourсe #XX -- [ Pg.612 , Pg.613 , Pg.614 ]




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