Metal noble

JS/oble Metals. Noble or precious metals, ie, Pt, Pd, Ag, and Au, are ftequendy alloyed with the closely related metals, Ru, Rh, Os, and Ir (see Platinum-GROUP metals). These are usually supported on a metal oxide such as a-alumina, a-Al202, or siUca, Si02. The most frequently used precious metal components are platinum [7440-06-4J, Pt, palladium [7440-05-3] Pd, and rhodium [7440-16-6] Rh. The precious metals are more commonly used because of the abiUty to operate at lower temperatures. As a general rule, platinum is more active for the oxidation of paraffinic hydrocarbons palladium is more active for the oxidation of unsaturated hydrocarbons and CO (19). 

This alcohol reduction method is applied to the control of size and composition of not only the noble metal/noble metal [7] but the 3d-transition metal/noble metal nanoparticles [8] like magnetic FePt nanoparticles. 

Francoise L-M, Voglet N, Thierry L, Rudi A (2001) Evidence for the emission of alkali-metal-noble-gas van der Waals molecules from cavitation bubbles. Ultrason Sonochem 8(2) 151—158... 

Transition Metal-Noble Gas Complexes D. C. Grills and M. W. George... 

Sensor Cell Operating Mode. The simplest method of sensor operation is as a galvanic cell, whereby the sensor acts as a fuel cell and generates a current proportional to the gas concentration to be detected (1 ). However, when detecting certain species in air, it is difficult to obtain a counter-reference electrode in an acid system that will maintain the sensing electrode at a predetermined potential of approximately 1.0 V, to minimize interference. Counter-reference electrodes such as Pt/air (Op) or noble metal/ noble metal oxide structures have rest potentials in the 1.0 to... 

Close-packed structures (ccp and hep) are very common for metals, noble gases, and many highly symmetrical molecules (Section 4.5). Flowever, 18 metals have the body-centered cubic (bcc) structure under ordinary conditions, and at least 25 metals have the bcc structure at higher temperature or pressure. Hence, at least 44 metals have the bcc structure as the primary structure or one of the allotropic forms,... 

Metals. Noble metals, especially when finely divided, cause explosive decomposition manganese and iron ignite on contact13 cobalt, iron, lead, manganese, mercury, nickel, and their oxides (especially rust) promote decomposition and must be excluded when using peroxides potassium and sodium are oxidized violently.15... 

O. S. Jina, X. Z. Sun and M. W. George, Do early and late transition metal noble gas complexes react by different mechanisms A room temperature time-resolved infrared study of (z)5-C5H5)Rh(CO)2 (R = H or Me) in supercritical noble gas solution at room temperature. Dalton Trans., 1773-8 (2003). 

There appears to be little doubt that the Mott criterion given by eq 3 is an effective indicator of the critical condition at the M-NM transition itself. At the least, this simple criterion provides a numerical prediction for the metal-nonmetal transition in many situations. Figure 10 summarizes some of the experimental data.34-36 Interestingly, besides doped semiconductors, metal—ammonia and metal—noble gas systems and superconducting cuprates all follow the linear relation given by eq 3. This is truly remarkable. 

Conclusions Future Perspectives in Transition Metal-Noble Gas Bonding... 

Despite the fact that a transition metal-noble gas complex has been isolated only very recently, the study of nohle gas coordination of transition metals actually has a long history. Early experiments used the technique of matrix isolation 18). Under the cryogenic conditions of frozen inert matrices, highly reactive photoproducts become sufficiently long-lived to allow their detection at leisure by conventional spectroscopic techniques such as UV/visible, IR, and EPR spectroscopy. 

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