Origin and Composition

The study of extraterrestrial spherules in Fig. 18.30 (a, b) was initially retarded by their small size (less than 1 mm)  

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The origins and composition of plastics wastes and factors affecting their recycling are discussed. Partieular attention is paid to chemical recycling and incineration, with and without energy recovery, and a number of developments in chemical recycling techniques are examined. 19 refs. 

Yamazaki K., Beauchamp G., Singer A., Bard J. and Boyse E. (1999). Odortypes their origin and composition. Proc Natl Acad Sci 96, 1522-1525. 

Table 2.1 lists specific radionuclides that may be present in nuclear fuel rods or industrial sources used to construct a dirty bomb. It also lists the radiological half-lives of each radionuclide, whether they are present in fresh or spent fuel rods, and their potential industrial applications. Note that the actual suites of isotopes for given fuel rods will vary depending on the origin and composition of the original fuel mixture. The uranium and plutonium isotopes found in fuel rods may also be found... 

Braitsch, 0., "Salt deposits their origin and composition,"... 

Martin JB (1993) Origins and Composition of Fluids at Convergent Margins, PhD Dissertation, Scripps Institution of Oceanography, La Jolla, California... 

Herzog GF, Xue S, Hall GS, Nyquist LE, Shih C-Y, Wiesmann H, Brownlee DE (1999) Isotopic and elemental composition of iron, nickel, and chromium, in t>pe I deep-sea spherules Implications for origin and composition of the parent micrometeoroids. Geochim Cosmochim Acta 63 1443-1457 Holland HD (1994) Early Proterozoic adnospheric change. In Early Life on Eardi, Noble Symposium No 84. 

With the aim of becoming independent of the individual origins and compositions of the various materials, we attempted to prepare, synthetically, an iron-containing catalyst equivalent in structure and in composition to the Magnetite of Gallivare (Sweden) which had proved, in repeated tests, to be an efficient and dependable catalyst. 

Simoneit, B. R. T., J. N. Cardoso, and N. Robinson, An Assessment of the Origin and Composition of Higher Molecular Weight Organic Matter in Aerosols over Amazonia, Chemosphere, 21, 1285-1301 (1990). 

Braitsch, O. 1971. Salt Deposits. Their Origin and Composition. Springer-Verlag, Berlin-Stuttgart-Heidelberg-New York, 297 pp. 

The concept of PAUR II is summarised schematically in the following way Stratospheric ozone variations, tropospheric ozone variations, aerosol origin and composition variations UV-B flux variations and variations in photodissociation rates Induced modulation and feedback of tropospheric O3 and other photochemical species Comparison of calculations with campaign observations. 

We describe herein an investigation of the photochemical reactivity of five PAHs (anthracene, phenanthrene, pyrene, benzo[a]pyrene, and benz[a]anthracene) adsorbed on various coal ashes of widely diverse origin and composition. Each PAH was deposited on each coal ash from the vapor phase to attempt to simulate the adsorption of combustion-produced PAHs onto atmospheric particles (5) ... 

Whole mixture approach for unique mixtures. This is an option if dealing with a mixture of completely unknown or unique origin and composition. In this case, results of previous effect studies cannot be used to assess the effects of the mixture of concern. Determination of a safe concentration level or a dose-response relationship for these mixtures is inefficient, as the effect data cannot be reused to assess the risks of other mixtures. The mixture of concern has to be tested directly in the field or the laboratory, like in the whole effluent toxicity (WET) test, resulting in a direct indication of the potential effects. 

Stars form in dense cores within giant molecular clouds (see Fig. 1.4, Alves et al. 2001). About 1 % of their mass is in dust grains, produced in the final phases of stellar evolution. Molecular clouds are complex entities with extreme density variations, whose nature and scales are defined by turbulence. These transient environments provide dynamic reservoirs that thoroughly mix dust grains of diverse origins and composition before the violent star-formation process passes them on to young stars and planets. Remnants of this primitive dust from the Solar System formation exist as presolar grains in primitive chondritic meteorites and IDPs. 

The application of the linear model will be shown for cesium-137 and strontium-85 ions. Cs-137 and the different strontium isotopes, especially Sr-90, are important components of nuclear wastes. As seen previously in Table 3.2, the cesium ion has a different sorption property on bentonite samples from the Sajobabony deposit, depending on geological origin and composition. Similarly, different bentonite rocks from the Carpathian Basin (Table 3.4) show different sorption properties, including kinetics and equilibrium (Figure 3.4, Table 3.5 Nagy et al. 2003b Konya et al. 2005). 

The acquisition of a lipid bilayer from the infected host cell is the defining feature of enveloped viruses. However, the origin and composition of the bilayer can differ from virus to virus. Viruses are known to acquire a membrane, or bud, from various cellular compartments that include the nucleus, the endoplasmic reticulum (ER), the Golgi, and the plasma membrane. As the Upid contents of those membranes differ, so do the contents of the viral membranes. In some, if not all, cases the composition of the lipid bUayer is an important aspect of the viral assembly pathway. 

Lewis J. S. (1988) Origin and composition of Mercury. In Mercury (eds. L. Vilas, C. R. Chapman, andM. S. Matthews). University of Arizona Press, Tucson, pp. 651 -666. 

Gallet S., Jahn B.-M., van Vliet Lanoe B., Dia A., and Rossello E. (1998) Loess geochemistry and its implications for particle origin and composition of the upper continental crust. Earth Planet. Sci. Lett. 156, 157-172. 

Even Precambrian Shield regions exhibit remarkable variability in heat production. For example, the exposed part of the Proterozoic Trans-Hudson Orogen in Saskatchewan and Manitoba ( 500 km X 500 km) is a mosaic of different belts of different origins and compositions with different heat production values (Rolandone et al, 2002). Another example is provided by the Abitibi province of eastern Canada, which stands out as a low-heat-production region within the Archean Superior Province (Mareschal et al., 2000a). 

Questions of the origin and composition of marine macromolecular organic matter continue to challenge us. A key point that has emerged, especially from NMR studies, is that the formation of randomly cross-linked macromolecules... 

Suppose we wish to determine the amount of phase A in a mixture of phases A, B, C,..., where the relative amounts of the other phases present (B, C, D,...) may vary from sample to sample. With a known amount of original sample we mix a known amount of a standard substance S to form a new composite sample. Let Ca and be the volume fractions of phase A in the original and composite samples, respectively, and let be the volume fraction of S in the composite sample., If a diffraction pattern is now prepared from the composite sample, then from Eq. (14-2) the intensity of a particular line from phase A is given by... 

RECENT NMR STUDIES ON THE ORIGIN AND COMPOSITION OF HUMIN IN AQUATIC (MARINE) SEDIMENTS... 

Braitsch, O., 1971. Salt deposits their origin and composition. Springer, New York, N.Y., 297 pp. 

Poupinet, G., Arndt, N., and Vacher, P., 2003. Seismic tomography beneath stable tectonic regions and the origin and composition of the continental lithosphere. Earth Planet. Sci. Lett., 212, 89-101. 

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