Metal distribution

Mercury amalgamates readily with gold and silver, and systems have been developed using these metals distributed on various carriers to remove mercury vapor from an akstream. When the system is saturated, the mercury can be removed easily and recovered by heating the unit and condensing the mercury. Other metals, such as copper and 2inc, can also be used. 

The procedure of determination of metals in the thin layer without elimination of the non-volatile organic components for different paints containing inorganic pigments was developed. Several techniques of sampling from paint-and-lacquer materials for X-ray fluorescence analysis were proposed. For the study of nonhomogenity of metal distribution in the thin layer we used additionally the local method of X-ray fluorescence analysis. 

Because of the industrial magnitude of these processes, many catalysts have been examined with variations in metal distribution, pore size, and alkalinity. In most synthetic work where catalyst life and small variations in yield are not of great importance, most palladium-on-carbon or -on-alumina powder catalysts will be found satisfactory for conversion of phenols to cyclohexanones. Palladium has a relatively low tendency to reduce aliphatic ketones, and a sharp decrease in the rate of absorption occurs at about 2 mol of consumed hydrogen. Nickel may also be used but overhydrogenation is more apt to occur. 

This is the ratio in which the current would divide, if electrolytic resistance were to control its flow entirely. The metal distribution ratio M is the ratio of the thicknesses of the coating actually deposited during a measurement. There are several numerical scales of throwing index T, but Field s is widely adopted ... 

The Hull cell cathode has a continuous variation of current density along its length, and there are equations which give the primary current density at any point not too near the end. If the local thickness is measured at two points for which P is known, Tcan be calculated. The real current distribution is a function of cathode and anode polarisation as well as of the resistance of the electrolyte. The metal distribution ratio will be... 

Metal Distribution Ratio the ratio of the thicknesses of metal produced during electroplating on two specified parts of the cathode. 

In addition to obtaining Information about the size, relative mass, and structure of the platinum crystallites, the STEM can provide a qualitative evaluation of the metal distribution from support particle to support particle. In general, the distribution of platinum was more uniform on alumina than silica, however, optimal uniformity was not achieved. This observation was based on wide variations In Pt/Sl and Pt/Al ratios measured by EDS. 

Although the metal distribution was not uniform, there was no Indication of large crystallites that might alter the Interpretation of Che results discussed above. 

Ir catalysts supported on binary oxides of Ti/Si and Nb/Si were prepared and essayed for the hydrogenation of a,P-unsaturated aldehydes reactions. The results of characterization revealed that monolayers of Ti/Si and Nb/Si allow a high metal distribution with a small size crystallite of Ir. The activity test indicates that the catalytic activity of these solids is dependent on the dispersion obtained and acidity of the solids. For molecules with a ring plane such as furfural and ciimamaldehyde, the adsorption mode can iirfluence the obtained products. SMSI effect (evidenced for H2 chemisorption) favors the formation of unsaturated alcohol. 

Feijtel T.C., Delaune R.D., Patrick Jr. W.H. Biogeochemical control on metal distribution and accumulation in Louisiana sediments. J Environ Qual 1988 17 88-94. 

Predictions no abundance gradients the thick disk thin disk stars will all have [Fe/H] larger than found in the thick disk period of star formation in thick disk was short < 1 billion years thin disk always younger than thick disk Observations no vertical gradients metallicity distributions for the disks overlap star formation in thick disk includes SNela and AGB star formation in thick disk probably > 1 billion years... 

In the left panel of Fig. 1 we present the [Fe/H] distributions for planet host stars (hashed histogram) included in the CORALIE planet-search sample [25], when compared with the same distribution for 900 stars in the whole CORALIE program (open histogram). The knowledge of the uniformly determined metallicity distribution for stars in the solar neighborhood (and included in the CORALIE sample) permits us to determine the percentage of planet host stars per metallicity bin. 

The old thin disk and thick disk populations are deconvolved from the velocity-metallicity distribution of the sample and their parameters are determined. The thick disk is found to have a moderate rotational lag with respect to the Sun with a mean metallicity of [Fe/H] = —0.48 0.05 and a high local normalization of 15 7%. 

The metallicity distribution of globular clusters in the Galaxy has a metal-rich peak at [Fe/H] -0.5 and a metal-poor peak at [Fe/H] -1.6 (e.g. Cote 1999), where most of the metal-rich ones are bulge clusters. Metallicities for samples of field stars were derived by McWilliam Rich (1994, hereafter MR94), Sadler et al. (1996), Ramirez et al. (2000). Zoccali et al. (2003) presented the... 

The metallicity distribution function (MDF) is an indicator of the enrichment history of a system. Large samples can be obtained [4,5] using low resolution... 

Fig. 1. Metallicity distribution of our sample of 35 giants. Bins are 0.2 dex wide...

The Extreme Ends of the Metallicity Distribution in dSph Galaxies... 

The Metallicity Distribution and Its Gradients in the LMC via Calcium Triplet Spectroscopy... 

Abstract. We present a new calibration of the Call triplet as metallicity indicator based in 4 globular and 11 open clusters which cover a range of metallicity -2<[Fe/H]<+0.1 and age 13<(Age/Gyr)<0.25. We use it to derive the metallicity distribution in two fields situated at 5 and 8 degrees from the center of the LMC. We show that the mean [Fe/H] of the LMC field decreases as we move away from the bar. 

Fig. 1. a) Linear correlation between metallicity, in the Carreta Gratton (1997) scale versus W . Triangles are the open clusters, open circles are the globular clusters and open stars are the data by [2]. b) Metallicity distribution for the field situated at 5° (dashed line) and 8° (solid line) from the bar. The amount of stars with metallicity bellow [Fe/H]=-1 increases at larger distances from the bar. 

Fig. 1. The metallicity distribution of Sgr. The bottom panel shows the metallicities for all our sample of stars, the second peak at metallicity about -1.5 is due to the presence of M54, in the middle panel only stars outside the tidal radius of M54 are histogrammed, and in the top panel only stars inside the tidal radius of M54.

Fig. 1. Left panel Metallicity distribution for our 487 red giants in Carina. The dashed line is the best-fit model prediction from [3]. The right plot shows spatially separated MDFs in three different regions of Carina, measured along the major and minor axes.

Our results suggest that dSphs contain multiple stellar components with different spatial, kinematic and metallicity distributions, and rule out formation scenarios involving single bursts of star formation. 

The metallicity distribution function (MDF) in galaxy halos contains other important clues about the process of galaxy formation. In recent years, a wealth of MDF data have been collected for the Milky Way (eg. [3], [4]), M3I (eg. [I]),... 

As can be seen from the metallicity distribution (see Fig. 1, upper panel), the mean metallicity of the Sgr dominant population is <[Fe/H]>=-0.49 0.19, in excellent agreement with the results derived in [5] from the magnitude of the RGB-bump and the shape of the Red Giant Branch. A component extending towards lower metallicities is also present. The a element abundance ratio (see Fig. 1, bottom panel) is slightly subsolar, <[a/Fe]>=-0.20 0.10, in agreement with [2] and, apart from a small offset, also with [7],... 

Fig. 1. Upper panel metallicity distribution for the 22 stars analyzed so far. Lower panel a element abundance ratio vs iron abundance for 20 stars of the sample. The [a/Fe] abundance ratio is the average of [Mg/Fe] and [Ca/Fe]. A typical errorbar is also plotted.

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