Amorphous deposit

Fine-grained polycrystals Amorphous deposits Gas-phase nucleated snow... 

Solvent for Electrolytic Reactions. Dimethyl sulfoxide has been widely used as a solvent for polarographic studies and a more negative cathode potential can be used in it than in water. In DMSO, cations can be successfully reduced to metals that react with water. Thus, the following metals have been electrodeposited from their salts in DMSO cerium, actinides, iron, nickel, cobalt, and manganese as amorphous deposits zinc, cadmium, tin, and bismuth as crystalline deposits and chromium, silver, lead, copper, and titanium (96—103). Generally, no metal less noble than zinc can be deposited from DMSO. 

Pressure is low (1-2 Torr) and amorphous deposits are obtained in the temperature range of400-540°C. 

Correlation functions hoo(R) for the amorphous deposit prepared and studied at 77 K are shown in Fig. 7b together with the curve for polycrystalline ice Ih. As in the crystalline phase, the nearest-neighbor oxygen-oxygen correlations in H20(as) occur in an exceptionally narrow band centered at 2.76 A, with rms-deviation 0.114 A. The distance ratio for second and first neighbors indicates tetrahedral coordination on the average, but the second neighbor peak near... 

The presence of sodium urate in the amorphous deposits in a jug found in 1903, but dating back to the Middle Ages, suggests that it was used to store urine, from which the urate precipitated as the urine evaporated. But why was urine stored in a jug in the Middle Ages Perhaps because drinking urine was highly recommended at this time for treatment of bubonic plague and other diseases Lancet, July 11, 1942). 

Again, double liquid treatments of HMDS did not prove adequate for polysilicon gate substrates, substrates comprised of amorphous deposited silicon as... 

When found in heat exchangers, carbonate is usually present as a hard, dense, white-to-tan or brown scale. A tan-to-brown color usually indicates the presence of iron. When found in cooling towers (for example, in the tower film-fill), it is often found as a softer, friable, white-to-tan, amorphous deposit. Samples of scales and deposits will normally fizz when tested with concentrated HC1 if carbonate is present. 

Gas Phase Nucleation Amorphous Deposits Fine Grained Deposits Poiycrystais Dendrites Whiskers Piateiets Epitaxiai Growth... 

Galvanostatic electrosynthesis of an Y-Ba-Cu oxide precursor was accomplished [231]. The incorporation of yttrium into the oxide from the solution did not take place, so a YCU4 alloy was used as the substrate. In a saturated Ba(OH)2 solution, and also in 7.2 m KOH with Ba + additives, a loose black layer of amorphous deposit was formed on the anode surface. The layer spontaneously detached and fell to the bottom of the cell. Being annealed in air, it was transformed into a mixture of the YBCO, CuO, and Ba2Cu03 phases. 

Warts. Warts are conelike or droplike protuberances, sometimes found covered with an amorphous deposition, that are scattered in a random pattern on the inner fiber-wall surface in most softwoods and the fibers of some hardwood species (Figure 24). The wart structure, known collectively as the warty layer (IT), is manufactured by the living cell protoplast before cell autolysis 18, 19). The warty layer is ligninlike in nature but has no apparent physiological role it prob-... 

Columnar polycrystal Equiaxed polycrystal Amorphous deposit... 

If the depositing temperature is sufficiently low, an amorphous deposit structure is formed because the atoms absorbed on the substrate surface are strictly constrained to the specific location, thus no further migration takes place. Two examples are amorphous silicon (a-Si H) and silicon carbide (a-SiC H) films with a high... 

According to the morphological characteristics, the amorphous deposits of Si3N4 may be divided into three types ... 

Figure 6.11c and d indicate the third typical surface structure which is found in amorphous deposits prepared at a deposition temperature of 1400°C and pressure of 20 Torr. Large primary cones containing numerous small secondary pebble-like cones were formed. The surface of secondary cones is smooth and similar to that in Figure 6.11a. 

The crystalline deposits show remarkable brightness resulting from a preferred orientation of grains. Surface structures of crystalline deposits are significantly different from those of amorphous deposits. The microstructure characteristics of the crystalline deposits are strongly dependent on the deposition conditions, as shown in Figure 6.12a-c. 

In amorphous deposits, the initial adsorption and desorption steps with associated rate constants k and k, respectively, are reversible. However, a peptide with the P-peptide deposit is essentially trapped making k effectively zero for those molecules that are not at the interface with the solution. Finally, within the amorphous deposit, the P peptide that is not at the reaction interface in contact with the existing fibril has a rate of reorganization k, to the P-peptide that is effectively zero. 

LaViolette, R. A., Amorphous deposits with energies below the crystal energy. Phys. Rev. B 40, 9952 (1989). 

Figure 3.09 (a) Time variation of , the potential energy per atom in a 150-atom niekel-phosphorous amorphous deposit, as simulated by computer, (b) Logarithm of the distribution of potential energy minima, plotted against potential energy per atom. (After Stillinger and Weber, 1984). 

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