Ruthenium, chemical analysis

Ruthenium, (ethylenediaminetetraacetic acid)-chemical analysis, 1,488 Ruthenium, hexaammine-oxidation, 1,370 redox potential. 1,485... 

Chemical analysis of solids and solutions indicate that in all cases metallic ruthenium, platinum, and gold are deposited on copper. Ruthenium, deposit is restricted to approximately 0.33 of the copper surface atoms, demonstrating that the redox reaction between Cu and Ru3+ can occur only on some special copper sites [11]. With platinum or gold, for the highest amount of modifier introduced (M"+/Cu(s) > 100), a deposit larger than a monolayer is obtained, indicating that all accessible copper atoms and subsurface copper atoms are involved in the redox reaction [13]. 

The particles of ruthenium-alumina composite are spherical as shown in Fig. 2. The particle size distribution is narrow with an average diameter of 0.64 ijra, as shown in Fig. 3. A cumulative surface area of 1.9 ra2/g is obtained from the distribution curve. Comparison between the cumulative and BET (5.4 m2/g) surface areas suggests that the particles are porous. The ruthenium content of the sample was determined to be 2.33 wt% by a chemical analysis. 

The chemical structure of the polymers was confirmed by NMR and elemental analysis, and spectroscopically characterized in comparison with monodisperse low molecular weight model compounds. Scheme 5 outlines the approach to the model compounds. Model compounds 31-34 were synthesized by complexation of the ruthenium-free model ligands 29/30 with 3/4. The model ligands were synthesized in toluene/diisopropylamine, in a similar fashion as the polycondensation using Pd(PPh3)4 and Cul as catalyst (Sonogashira reaction) [34,47-49]. 

Slow chemical exchange in an eight-coordinated bicentered ruthenium complex studied by one-dimensional methods. Data fitting and error analysis. J. Magn. Reson. Ser. A, 118 (1), 21-27. 

Direct labeling of a biomolecule involves the introduction of a covalently linked fluorophore in the nucleic acid sequence or in the amino acid sequence of a protein or antibody. Fluorescein, rhodamine derivatives, the Alexa, and BODIPY dyes (Molecular Probes [92]) as well as the cyanine dyes (Amersham Biosciences [134]) are widely used labels. These probe families show different absorption and emission wavelengths and span the whole visible spectrum (e.g., Alexa Fluor dyes show UV excitation at 350 nm to far red excitation at 633 nm). Furthermore, for differential expression analysis, probe families with similar chemical structures but different spectroscopic properties are desirable, for example the cyanine dyes Cy3 and Cy5 (excitation at 548 and 646 nm, respectively). The design of fluorescent labels is still an active area of research, and various new dyes have been reported that differ in terms of decay times, wavelength, conjugatibility, and quantum yields before and after conjugation [135]. New ruthenium markers have been reported as well [136]. 

A time resolution of approximately 10 ps is possible with the CFMIO method, although at such short times the mixing and chemical reaction take place simultaneously and the analysis becomes more complicated. Nonetheless, the method was used successfully in a study of the reactions of iron(III) and ruthenium(III) polypyridine complexes with several transition metal cyano compounds [3], but each experiment required approximately 300 mL of solution. The measured rate constants for electron transfer exceeded 3 x 10 M s . ... 

Little is known about the chemical nature of the recently isolated carbon clusters (C o> C70, Cg4, and so forth). One potential application of these materials is as highly dispersed supports for metal catalysts, and therefore the question of how metal atoms bind to C40 is of interest. Reaction of C o with organometallic ruthenium and platinum re nts has shown that metals can be attached directly to the carbon framework. Ihe native geometry of transition metal, and an x-ray difi action analysis of the platinum complex [(CgHg)3P]2Pt( () -C6o) C4HgO revealed a structure similar to that known for [(C4Hs)3P]2Pt( n -ethylene). The reactivity of C40 is not like that of relatively electron-rich planar aromatic molecules su( as benzene. The carbon-carbon double bonds of C40 react like those of very electron-deficient arenes and alkcnes. 

Smith, D.F., Wilhnan, K., Kuo, K., and Murray R.W. 1979. Chemically modified electrodes XV. Electrochemistry and waveshape analysis of aminophenylferrocene bonded to acid chloride functionalized ruthenium, platinum, and tin oxide electrodes. Journal of Electroanalytical Chemistry 95, 217-227. 

When the initial research on bimetallic clusters such as ruthenium-copper and osmium-copper was conducted, the characterization of the clusters was limited to methods involving chemical probes because of the difficulty of obtaining information with physical probes. In recent years, however, advances in X-ray absorption spectroscopy have changed the situation markedly. In particular, improvements in methods of obtaining extended X-ray absorption fine structure (EXAFS) data with the use of synchrotron radiation (13), in conjunction with advances in methods of data analysis (14), have made EXAFS a valuable tool for obtaining structural information on bimetallic clusters. 

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