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Metal defined

The fate of stars also depends on the presence of a companion. Other violent episodes known as Novae or type la supemovae result from the accretion of materials from a partner star. Supemovae of type I are thought to be responsible for most of the production of the neutron-rich isotopes of the iron group (Woosley et al. 1995 Hoflich et al. 1998). One of the key parameters in stellar evolution, and consequently the nucleosynthetic outcome, is the metallicity, defined as the proportion of elements heavier than He. [Pg.30]

Figure 2.2 Illustration of the cell vectors of the fee metal defined in Eq. (2.4). Figure 2.2 Illustration of the cell vectors of the fee metal defined in Eq. (2.4).
Consider an uncharged metal and an electron just outside the metal.31 The change of energy at a given temperature and pressure when the electron moves from the point just outside to the point inside the metal defines the binding energy of the electron to the material.32 Consider now the reverse process, that is, when the electron... [Pg.117]

The metallicity defined here, as well as the simpler earlier form, corresponds roughly to the metallization introduced earlier by Mooscr and Pearson (1959). It is also the parameter (based upon earlier values) that formed the ordinate in the schematic phase diagram shown in Fig. 2-6. [Pg.89]

Ligands attached to a metal define the coordination sphere" of the central atom or ion. [Pg.209]

Under ambient conditions elemental sulfur is one of the best electrical insulators known. In fact, sulfur is the prototype of a non-metal defined as a material of zero electrical conductivity at 0 K. However, this statement applies to ambient pressures only. At very high pressures sulfur—like other typical non-metals—becomes an electrical conductor and, at very low temperatures, even a superconductor [117]. Because of the very low conductivity at standard conditions (e.g., 10 1 cm at 550 °C) impurities play a major role and those studies which reported the lowest conductivity must be considered the most trustworthy. [Pg.106]

Immersion of a copper crystal in an electrolyte solution containing the metal ion fixes the electrochemical potential fi of the metal, defined as the partial derivative of the total Gibbs free energy G of the solid phase with... [Pg.135]

The reaction is important because it aiiows the coupiing of two different components (R and R2), distinguished by being bonded either to the metai M or to the halide or triflate X. Both components form a compiexes with Pd but the haiide partner (R X) bonds first by oxidative addition and this R —Pd bond must survive whiie the metal partner (R M) transfers R to Pd by transmetallation. Once the two components are joined to the palladium atom, only the cross-coupled product can be formed. R X combines with Pd(0) and R M with Pd(II). There can then be no confusion. In contrast to the Heck reaction, here the metal defines the location of the new C—Pd bond. [Pg.1083]

Draw an anodic polarization curve for an active-passive metal. Define in words and indicate on the figure all characteristic potentials, potential regions and current densities. [Pg.62]

Although during the first years of development of sequential extraction almost every researcher had his own sequence, made on the basis of more or less free selection of extraction instruments and order of their use, recently there has been relative unification of applied models, and hence there is a possibility of appropriate comparison of findings made by various authors. Since selectivity of certain extractors is already relatively well known, and so are the effects of secondary reactions, re-adsorption and other obstructing occurrences, the authors seldom use - in essence inadequate - notions such as exchangeable phase , easily reducible phase , etc. but more frequently use notions such as ammonium-acetate phase , hydroxylamine phase , etc. Therefore, isolated metal fractions are ascribed to applied extraction instruments, naturally with clearly defined conditions for extraction, which have been more or less standardized for each extraction level. In order to ascribe fractions of heavy metals, defined in this manner, to a certain substrate, one has to know to what extent were the most widely spread substrates susceptible to the effect (breakdown, i.e. dissolving) of applied extraction instruments. [Pg.296]

Ceramic Coating (on Metal). Defined (ASTM - C286) as An inorganic essentially non-metallic, protective... [Pg.55]

Prussian blue is made by mixing together aqueous solutions of FeCl3 and K4pe(CN)6, which contains [FefCN) ] - ions, a State the oxidation states of the iron ions in each of these solutions, b Describe the shape of the [Fe(CN)g] ion. c Iron is a transition metal. Define the term transition metal. [Pg.488]


See other pages where Metal defined is mentioned: [Pg.257]    [Pg.21]    [Pg.6]    [Pg.7]    [Pg.114]    [Pg.203]    [Pg.149]    [Pg.153]    [Pg.146]    [Pg.426]    [Pg.235]    [Pg.186]    [Pg.336]    [Pg.47]    [Pg.90]    [Pg.187]    [Pg.2]    [Pg.332]    [Pg.63]   
See also in sourсe #XX -- [ Pg.77 ]

See also in sourсe #XX -- [ Pg.46 , Pg.416 ]

See also in sourсe #XX -- [ Pg.134 ]

See also in sourсe #XX -- [ Pg.55 , Pg.524 ]

See also in sourсe #XX -- [ Pg.7 , Pg.927 ]




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