Metallization density

Weight loss X 534 (Area)(time)(metal density)... 

Area)(time)(metal density) where weight loss is in mg, area is in in" of metal surface exposed, time is in hours exposed, and density is in g/cm. Densities for alloys can be obtained from theproducers or from various metal handbooks. 

Substrate metal Density (g cm-3) Coating Density (g cm-3) Coating thickness ( m) Anode current density (A m ) max. avg. Allowable maximum driving voltage (maxA ) Loss (mg A a )... 

Vh = vapor velocity through valve holes, ft/sec P = tray aeration factor, dimensionless AP = tray pressure drop, in. liquid pvm = valve metal density, tj = tray deck thickness, in. 

Pvm = Valve metal density, Ib/ft a = Surface tension of liquid, dy nes/cm... 

The oxygen vacancies then diffuse to the gas interface where they are annihilated by reaction with adsorbed oxygen. The important point, however, is that metal is consumed and oxide formed in the same reaction zone. The oxide drift has thus only to accommodate the net volume difference between the metal and its equivalent amount of oxide. In theory this net volume change could represent an increase or a decrease in the volume of the system, but in practice all metal oxides in which anionic diffusion predominates have a lower metal density than that of the original metal. There is thus a net expansion and the oxide drift is away from the metal. 

Metal Density (g cm- ) Molecular weight (g mor ) Theoretical weight for 100% efficiency (g) Theoretical thickness at 100% current efficiency (mm cm ) Typical current efficiency (C.E.) obtained in practice (%) Actual thickness for typical current efficiency (mm cm )... 

Recently, ultrathin evaporated films have been used as models for dispersed supported metal catalysts, the main object being the preparation of a catalyst where surface cleanliness and crystallite size and structure could be better controlled than in conventional supported catalysts. In ultrathin films of this type, an average metal density on the substrate equivalent to >0.02 monolayers has been used. The apparatus for this technique is shown schematically in Fig. 8 (27). It was designed to permit use under UHV conditions, and to avoid depositing the working film on top of an outgassing film. ... 

Tank diameter Nozzle diameter Friction factor Acceleration of gravity Tank height Effective head Nozzle length Mass Pressure Metal density Reynolds number time... 

Fig. 28. Dishing observed in tungsten polishing as a function of metal density [12], Reproduced by permission of the Electrochemical Society, Inc.

Silvery metal density 13.51 g/cm (calculated) atomic volume IScm /mole melts in the range 1,300 to 1,380°C magnetic susceptibihty 12.2xl0-8cgs units/mole at 25°C dissolves in mineral acids. 

Silver-white lustrous soft metal highly malleable and ductile face-centered tetragonal crystalline structure (a=4.583A, c=4.93GA) diamagnetic metal density 7.31 g/cm at 20°C melts at 156.6°C vaporizes at 2,072°C electrical resistivity 8.4 x Kh ohm-cm superconducting at 3.38°K (—269.8°C) hardness 0.9 (Brinnel) tensile strength 26.19 atm modulus of elasticity 10.8 GPa thermal neutron absorption cross-section 190 10 bams soluble in acids. 

Silvery-white metal density 7.22 g/cm because of radioactivity, the metal and its salts luminesce in the dark giving a pale blue or greenish glow melts... 

Appendix 6. Factors and Metal Densities Needed to Obtain ipy and mdd Corrosion Rates... 

We see that eqn (5.63) mirrors the behaviour found in Fig. 5.14 for sodium by Wigner and Seitz. At metallic densities the bottom of the conduction band is well described by the first contribution in eqn (5.63). As the atoms are brought together, the bonding state becomes more bonding until eventually the repulsive core contribution dominates, and the bottom of the conduction band rises rapidly. From eqn (5.63) the maximum binding energy of this state occurs for... 

We will find that the Thomas-Fermi approximation totally fails to distinguish correctly between the different competing close-packed structure types such as fee, bcc or hep. We must, therefore, go beyond the Thomas-Fermi approximation and evaluate the proper screening behaviour of the free-electron gas at equilibrium metallic densities. 

Fig. 6.4 The radial charge distribution of the screening clouds around sodium, potassium, magnesium, and aluminium ions in free-electron environments of the appropriate equilibrium metallic densities. The arrows mark the positions of the first nearest neighbours in hep Mg and fee Al, the first and second nearest neighbours in bcc Na and K. (After Rasolt and Taylor (1975) and Dagens et al. (1975).)...

At normal metallic densities, the six poles are complex, so that we may assign... 

The transition-metal density of states n(E) is not uniform throughout the band, as shown schematically in Fig. 7.4 but displays considerable structure that is characteristic of the given crystal lattice. This is seen in.Fig. 7.6,... 

It can be seen that the chemisorption function, A(e), can be regarded as a local projection of the metal density of states around the adsorbate. 

The group-orbital projected metal density of states, nd(e). can be characterized by its moments ... 

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