Elemental ratios

Eig. 19. CME monopolar electrolyzer a, membrane b, cathode element c, half-cathode element d, current distributor e. Teflon tube f, CI2 + depleted brine manifold g, conductor rod h, CI2 + depleted brine outlet nozzle i, base frame j, recycled NaOH manifold k, recycled NaOH inlet nozzle 1, gasket (the gasket-to-element ratio is quite small) m, tie rod n, anode element o, H2 + NaOH manifold p, end plate, q, under cell bus bar (simplifies piping... 

The special interest is the determination of Fe, as the acceleration of sclerosed process is connected with the accumulation of Fe in this organ. Copper is accumulated in tissues at the genetic caused diseases (Wilson Disease, Hemochromatosis). This is the alteration in elemental ratios (e.g., Cu/Zn), that is the marker of pathological process. 

EXAMINATION OF THE CHEMICAL ELEMENTS RATIOS IN HUMAN NAILS (SRXRF)... 

Analysis Ultra clean analysis Element ratios Element ratios... 

Aggradation or degradation of biomass or soil reservoirs may also produce effects that appear to be fractionation. This is because the elemental ratios in vegetation or soil reservoirs can be very different from those of bedrock. Sufficiently large and rapid changes in these reservoirs are sometimes evident in river chemistry. For example, the uptake and release of potassium in association with the seasonal growth and loss of leaves can affect the composition of streams that drain temperate deciduous forests (Likens et al, 1977 Vitousek, 1977). 

This equation was originally proposed for "average" plankton, a category that included both zooplankton and phytoplankton. This mean elemental ratio of C/N/P = 106/16/1 by atoms is highly conserved (Falkowski et al., 1998) and reflects the average biochemical composition of marine phytoplankton and their early degradation products. 

If the sample is pure (this can generally be checked by thin layer chromatography or gas chromatography) then the elemental analysis values for carbon, hydrogen and nitrogen can be used to obtain element ratios, provided that C, H, N and 0 are the only elements present. 

Abstract. In this contribution we present the results based on high-resolution spectra of 45 clump stars of the Galactic field. The main atmospheric parameters and abundances of 12C, 13C, N, O and other mixing sensitive chemical elements were investigated. Elemental ratios in the sample of field stars are compared to the results available for evolved stars in open clusters and to the theoretical prediction of extra mixing in stellar interiors. 

Fig. 2. Distribution of element ratios vs metallicity for the sample of giants...

Fig. 1. Element ratio data for Galactic field stars (dots) compiled by Venn et al. (2004). [The open squares are stars in dSph galaxies.] The important point to notice here is the very small scatter in element abundances for Galactic field stars at any given [Fe/H] value, over 4dex in [Fe/H].

Figure 2 above illustrates a similarity in at least one fundamental parameter between the Bulge and the stellar halo. The stellar halo traced by stars passing near the Sun is some 30% of its total mass of 2 x 109Mq. These stars are predominantly old and metal poor. They show remarkable uniformity in their relationship between the element ratios and the total metal abundance (Figure 1), with implications noted above. 

Figure 1 above) have shown there is a very small scatter in element ratios at any [Fe/H] value, particularly within a stellar population, yet there is an extremely large scatter in the age-[Fe/H] relation at every age (Nordstrom et al. 2004). Linking the local and global remains a challenge. 

Fig. 1. Heavy over light s-elements ratio versus metallicity. Lines are theoretical predictions for a 1.5M AGB stars with C/0=1.1 and three different choices for the neutron exposure rate (see Busso et al., 2001, ApJ, 557, 802). Black dots are for galactic carbon stars analyzed in Abia et al. (2002, ApJ 578, 817).

Unlike XRES, which yields information as elemental ratios and from comparisons with standard samples of known composition, EELS is capable of yielding absolute results, i.e. the composition is derived without reference to a standard. The concentration,... 

Negrel Ph, Allegre CJ, Dupre B, Lewin E (1993) Erosion sources determined by inversion of major and trace element ratios and strontium isotopic ratios in river water the Congo Basin case. Earth Planet Sci Lett 120 59-76... 

Figure 5. Correlation of 27AT/uMg secondary ion intensity ratios vs. 27Al/MMg elemental ratio measured with the electron probe for Allende anorthite (0) and terrestrial plagioclase W-...

---