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Properties of the Metal

Mott, N.F. and Jones, H. (1936) The Theory of the Properties of Metals and Alloys (Oxford University Press, London). [Pg.152]

The upshot of all this research since 1954 is rather modest, with the exception of the GE research, which indicates that techniques and individual materials have to be married up an approach which is crucial for one material may not be very productive for another. This is of course not to say that this 40-year programme of research was wasted. The initial presumption of the potential value of ultra-pure metals was reasonable it is the obverse of the well-established principle that minor impurities and dopants can have major effects on the properties of metals. [Pg.358]

The diagonal line or stairway that starts to the left of boron in the periodic table (Figure 2.7, page 31) separates metals from nonmetals. The more than 80 elements to the left and below that line, shown in blue in the table, have the properties of metals in particular, they have high electrical conductivities. Elements above and to the right of the stairway are nonmetals (yellow) about 18 elements fit in that category. [Pg.33]

A. Sommerfeld and H. Bethe, "Handbuch der Physik," Voi. 24, second edition N. F. Mott and H. Jones, "The Theory of the Properties of Metals and Alloys," Oxford University Press, Oxford, 1936 F. Seitz, "The Modern Theory of Solids," McGraw-Hill Book Co., New York, N. Y., 1940. [Pg.350]

I feel now that I was influenced to some extent by my knowledge that in 1926 Goldschmidt had formulated a set of atomic radii that represented reasonably well the interatomic distances in both covalent crystals and metals (5). I was also impressed by a discussion of the properties of metals by Bernal, who, however, rejected the idea that covalent bonds are present in metals (4). Bragg also rejected this idea (5). [Pg.397]

As described in Section 10-, the bonding in solid metals comes from electrons in highly delocalized valence orbitals. There are so many such orbitals that they form energy bands, giving the valence electrons high mobility. Consequently, each metal atom can be viewed as a cation embedded in a sea of mobile valence electrons. The properties of metals can be explained on the basis of this picture. Section 10- describes the most obvious of these properties, electrical conductivity. [Pg.780]

Substitutional impurities replace one metal atom with another, while interstitial impurities occupy the spaces between metal atoms. Interstitial impurities create imperfections that play important roles in the properties of metals. For example, small amounts of impurities are deliberately added to iron to improve its mechanical... [Pg.801]

Non-situ and ex situ studies can provide important information for understanding the properties of metal/electrolyte interfaces. The applicability of these methods for fundamental studies of electrochemistry seems to be firmly established. The main differences between common electrochemical and UHV experiments are the temperature gap (ca. 300 vs. 150 K) and the difference in electrolyte concentration (very high concentrations in UHV experiments). In this respect, experimental research on double-layer properties in frozen electrolytes can be treated as a link between in situ experiments. The measurements of the work functions... [Pg.32]

The key to the successful development of homogeneous catalysts has been the exploitation of the effects that ligands exert on the properties of metal complexes by tailoring the electronic and steric properties of a catalytically active metal complex, activities and selectivities can be altered considerably. This especially holds for phosphorus based ligands, which are the most commonly encountered ligands as.sociated with organometallic compounds. [Pg.111]

If the above comparison of the properties of metal atoms with those of hydrogen deposited on the surface of a solid body (semiconductor) is correct, the effect of their adsorption on electric properties of semiconductor oxide films will be similar to features accompanying adsorption of hydrogen atoms. The atoms of hydrogen are very mobile and, in contrast to metal atoms, are capable of surface recombination resulting in formation of saturated molecules with strong covalent bond. [Pg.185]

Effects of Various Parameters on the Properties of Metal Nanoparticles... [Pg.141]

The effects of various parameters on the rates of sonochemical reduction of metal ions were described in the previous sections. From this section, the effects of such parameters on the properties of metal nanoparticles are described in relation to the rates of reduction. [Pg.141]

Brugmann [784] discussed different approaches to trace metal speciation (bioassays, computer modelling, analytical methods). The electrochemical techniques include conventional polarography, ASV, and potentiometry. ASV diagnosis of seawater was useful for investigating the properties of metal complexes in seawater. Differences in the lead and copper values yielded for Baltic seawater by methods based on differential pulse ASV or AAS are discussed with respect to speciation. [Pg.269]

Field emission microscopy was the first technique capable of imaging surfaces at resolution close to atomic dimensions. The pioneer in this area was E.W. Muller, who published the field emission microscope in 1936 and later the field ion microscope in 1951 [23]. Both techniques are limited to sharp tips of high melting metals (tungsten, rhenium, rhodium, iridium, and platinum), but have been extremely useful in exploring and understanding the properties of metal surfaces. We mention the structure of clean metal surfaces, defects, order/disorder phenomena,... [Pg.191]

The chemistry of metal oxides can be understood only when their crystal structure is understood. Knowledge of the geometric structure is thus a prerequisite to understanding the properties of metal oxides. The bulk structure of polycrystalline solids can usually be determined by x-ray... [Pg.42]

Ryan M. Richards was raised near Flint, Michigan. In 1994, he completed both B.A. in chemistry and B.S. in forensic science at Michigan State University. He then spent 2 years as an M.S. student at Central Michigan University working on organometallic chemistry with Professor Bob Howell. He was awarded a Ph D. in 2000 for investigating the properties of metal oxide nanoparticles in the laboratory of Professor Kenneth Klabunde at Kansas State University. In 1999, he was an invited scientist at the Boreskov Institute of Catalysis in Novosibirsk,... [Pg.539]

It is instructive to compare the properties of metal peroxo and alkyl (or hydro) peroxo groups for the case of Ti because experimental structures of both types are known [117, 119-121] and Ti compounds are catalysts for such important processes as Sharpless epoxidation [22] and epoxidation over Ti-silicalites [122], where alkyl and hydro peroxo intermediates, respectively, are assumed to act as oxygen donors. Actually, the known Ti(t 2-02) complexes are not active in epoxidation. [121-124] However, there is evidence [123] that (TPP)Ti(02) (TPP = tetraphenylporphyrin) becomes active in epoxidation of cyclohexene when transformed to the cis-hydroxo(alkyl peroxo) complex (TPP)Ti(OH)(OOR) although the latter has never been isolated. [Pg.312]

Know the properties of metals, nonmetals, and metalloids and which elements on the periodic table belong to each group. [Pg.65]

Another chapter (Chapter 4) is entitled Intermetallic reactivity trends in the Periodic Table . The Periodic Table, indeed (or Periodic Law or Periodic System of Chemical Elements), is acknowledged to play an indispensable role in several different sciences. Especially in inorganic chemistry it represents a fundamental classifi-catory scheme and a means of systematizing data with a clear predictive power. Inorganic chemists have traditionally made considerable use of the Periodic Table to understand the chemistry of the different elements. With a few exceptions (as detailed in the same chapter), metallurgists and intermetallic chemists have made little use of this Table to understand and describe the properties of metals and alloys we believe, however, that it may be a useful tool also in the systematics of descriptive intermetallic chemistry (as exemplified in the subsequent chapter (Chapter 5)). In several paragraphs of Chapter 4, therefore, different aspects of the Periodic Table and of its characteristic trends are summarized. [Pg.3]

Main uses of lithium alloys. Li additions often change completely the properties of metals to which it is added, for instance hardness of A1 and Pb (addition of Li to Pb results in the formation of Pb solid solution and a eutectic at 15.7 at.% Li with LiPb) and ductility of Mg. Al-alloys can be of great interest in aerospace industry Li (as Be) simultaneously reduces the density of A1 and increases its modulus of elasticity. Each 1 mass% Li up to the solubility limit (4.2 mass%) reduces density by about 3% and increases modulus by 5%. Precipitates homogeneously distributed of spherical LiAl3 in diluted Li-alloys during heat treatment may improve strength. [Pg.335]

Petit C, Mendoza B, O Donnell D, Bandosz TJ. Effect of graphite features on the properties of Metal-Organic Framework/Graphite hybrid materials prepared using an in situ process, Langmuir 2011, TJ, 10234-10242. [Pg.291]

These studies indicate that the charge transfer at the metal-oxide interface alters the electronic structure of the metal thin film, which in turn affects the adsorption of molecules to these surfaces. Understanding the effect that an oxide support has on molecular adsorption can give insight into how local environmental factors control the reactivity at the metal surface, presenting new avenues for tuning the properties of metal thin films and nanoparticles. Coupled with the knowledge of how particle size and shape modify the metal s electronic properties, these results can be used to predict how local structure and environment influence the reactivity at the metal surface. [Pg.16]

In the first epoch, the properties of metals were explored. New metals (zinc, arsenic, antimony, and bismuth) were discovered. The specific weights... [Pg.11]

Many of the properties of metal ions in aiding or discouraging reactions are beautifully illustrated in the work on the chemical synthesis of corrins. Thus, it is appropriate to conclude this chapter by a relevant quotation from Eschenmoser ... [Pg.325]


See other pages where Properties of the Metal is mentioned: [Pg.184]    [Pg.333]    [Pg.455]    [Pg.258]    [Pg.305]    [Pg.160]    [Pg.346]    [Pg.45]    [Pg.333]    [Pg.7]    [Pg.273]    [Pg.16]    [Pg.747]    [Pg.118]    [Pg.502]    [Pg.42]    [Pg.437]    [Pg.1006]    [Pg.385]    [Pg.16]    [Pg.133]    [Pg.427]    [Pg.333]    [Pg.299]   


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Properties of metals

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