Silver analysis

Dithionous acid, 23 669 Dithiopolyesters, 23 739 Dithiozone extraction method, silver analysis via, 22 651 Dithizone, molecular formula, 5 713t Ditins, 24 826... 

Inductively coupled plasma technique, silver analysis via, 22 651 Inductively heated furnaces, 12 739 Industrial activities, categories of, 25 917 Industrial alcohol, specifications for, 10 545 Industrial applications... 

Watanabe, H., Hayazawa, N., Inouye, Y, and Kawata, S. 2005. DFT vibrational calculations of rhodamine 6G adsorbed on silver Analysis of tip-enhanced Raman spectroscopy. J. Phys. Chem. B 109 5012-20. 

Since we do not weigh these streaks, we assumed that the Ag + Cu + Zn + As + Sb + Au = 100%. By comparing the radioactivity levels in the streaks with those in the standard alloy streaks (each corrected for decay to a common reference time) we can then calculate the percent ratios Cu/Ag, Au/Ag, Zn/Ag, Sb/Ag, and As/Ag. The combination of these ratio data and the above equation allows us to calculate the individual percent values. Various chemical analyses reported in the literature for silver coins and art objects indicate that other elements such as lead and tin (which we do not detect) are usually present at less than 2%. There are notable exceptions however. Some types of coins from certain periods contain up to 10-15% Pb + Bi. As a result, we have always performed direct neutron Howitzer silver analysis on at least a few coins of each general type that are analyzed by streak analysis. The silver data for the Howitzer analysis are invariably lower than those for the streak analysis, but this is to be expected for two reasons the... 

Hung et al. (1982) developed a sensitive and selective method for silver analysis by reacting silver (I) with 2(3,5-dibromo-2-pyridylazo)-5-diethyl amino phenol in the presence of an anionic surfactant, sodium lauryl sulfate. The ternary complex formed is red and exhibits an absorption peak at 570 nm. Hung and his co-workers employed EDTA as a chelating agent, thereby reducing the interference of common ions. Recoveries were good, and a detection limit of 0.39 ppm of silver was achieved. 

H. Watanabe, N. Hayazawa, Y. Inouye, and S. Kawata, Dft Vibrational Galcula-tions of Rhodamine 6g Adsorbed on Silver Analysis of Tip-Enhanced Raman Spectroscopy, J. Phys. Chem. B 109,... 

Silver Analysis at a Boron-doped Diamond Electrode... 

Estimate the limit of detection of the silver analysis from the data in Exercise 3. 

Mercaptan sulfur NF M 07-022 ISO 3012 ASTM D 3227 Silver nitrate analysis... 

Partial reflections at the iimer optical interfaces of the interferometer lead to so-called secondary and tertiary fringe patterns as can be seen from figure B 1.20.4. These additional FECO patterns become clearly visible if the reflectivity of the silver mirrors is reduced. Methods for analysis of such secondary and tertiary FECO patterns were developed to extract infonnation about the topography of non-unifonn substrates [54]. 

Figure Bl.22.6. Raman spectra in the C-H stretching region from 2-butanol (left frame) and 2-butanethiol (right), each either as bulk liquid (top traces) or adsorbed on a rough silver electrode surface (bottom). An analysis of the relative intensities of the different vibrational modes led to tire proposed adsorption structures depicted in the corresponding panels [53], This example illustrates the usefiilness of Raman spectroscopy for the detennination of adsorption geometries, but also points to its main limitation, namely the need to use rough silver surfaces to achieve adequate signal-to-noise levels.

Silver nitrate is used extensively in qualitative and quantitative analysis. 

In similar circumstances, silver salts leave a residue of metallic silver lead and copper salts usually leave a residue of the corresponding oxide calcium and barium salts leave a resirlne of the carbonate or oxide. Identify the metal in all such cases by the usual tests of qualitative inorganic analysis. Metals other than the above are seldom encountered in elementan qualitative analysis. 

I. Molecular Weight of Acids by Analysis of Silver Salts. 

The silver salts of most carboxylic acids are only sparingly soluble in cold water, and hence are readily prepared. Moreover they very rarely contain water of crystallisation, and therefore when dried can be analysed without further treatment. The analysis itself is simple, rapid and accurate, because gentle ignition of a weighed quantity of the silver salt in a crucible drives off the organic matter, leaving a residue of pure metallic silver. 

In qualitative organic analysis, use is made of the fact that silver iodate is sparingly soluble in dilute nitric acid whereas silver periodate is very soluble. For water-insoluble compounds solutions in ethanol or in pure dioxan may be employed. 

A more detailed perturbation theory analysis leads to an improved correction formula. This method, known as the Davidson and Silver or Siegbahn correction, is... 

Oxidation of a glycol can lead to a variety of products. Periodic acid quantitatively cleaves 1,2-glycols to aldehydes and is used as an analysis method for glycols (12,13). The oxidation of propylene glycol over Pd/C modified with Pb, Bi, or Te forms a mixture of lactic acid, hydroxyacetone, and pymvic acid (14). Air oxidation of propylene glycol using an electrolytic crystalline silver catalyst yields pymvic aldehyde. 

In addition to modem spectroscopic methods ( H nmr spectroscopy, ftir spectroscopy) and chromatographic methods (gc, hplc), HBr titration (29) is suitable for the quantitative analysis of ethyleneimine samples which contain relatively large amounts of ethyleneimine. In this titration, the ethyleneimine ring is opened with excess HBr in glacial acetic acid, and unconsumed HBr is back-titrated against silver nitrate. 

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