Grain size varying

Grain size varies widely, from 10 to 5000 nm. The grain size of fine-grained or banded deposits is usually 10—100 nm. Some metals, notably copper, nickel, cobalt and gold, can be deposited in all four types of grain stmcture, depending on the solution composition and plating conditions. 

Marbles are whitish grey in colour. They occur in the form of irregular elongated bodies, several metres in length. The grain size varies from a few millimetres to 7cm, representing different... 

In ionic liquids the situation seems to be totally different. It was surprising to us that the electrodeposition of metals and semiconductors in 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide delivers nanocrystalline deposits with grain sizes varying from 10 to 200 nm for the different materials, like Si, Al, Cu, Ag and In, investigated to date. It was quite surprising in the case of Al deposition that temperature did not play a tremendous role. Between 25 and 125 °C we always got nanocrystalline Al with similar grain sizes. Similar results were obtained if the deposition was performed in tri-hexyl- tetradecylphos-phonium bis (trifluoromethylsulfonyl) amide. Maybe liquids with saturated nonaromatic cations deliver preferentially nanomaterials this is an aspect which, in our opinion, deserves further fundamental studies. 

Sand—Sand is a coarse-grained, cohesionless soil with grain size varying from about in. to 0.05 mm. 

Chalk is a soft, fine-grained, fossiliferous form of calcium carbonate that varies widely in color, hardness, and purity. Its grain size is so minute that it appears amorphous, but actually it is cryptocrystalline with a very high surface area. 

The microstmcture and imperfection content of coatings produced by atomistic deposition processes can be varied over a very wide range to produce stmctures and properties similar to or totally different from bulk processed materials. In the latter case, the deposited materials may have high intrinsic stress, high point-defect concentration, extremely fine grain size, oriented microstmcture, metastable phases, incorporated impurities, and macro-and microporosity. AH of these may affect the physical, chemical, and mechanical properties of the coating. 

Particle size and cooking condition for the grain slurry vary depending on the type of distilled spirit that is to be produced. In the case of com grain fermentations, distillers use small size, high temperature, and low beer gallonage (higher starch concentrations) for neutral spirits production at 120—170°C and 76—91 L/0.03 m. Bourbon distillates call for low temperatures (100—150°C) and thinner mash of 95—115 L/0.03 m (saccharified starch slurries) out of flavor considerations. (0.03 m is approximately a bushel). 

The mechanical properties of Watts deposits from normal, purified solutions depend upon the solution formulation, pH, current density and solution temperature. These parameters are deliberately varied in industrial practice in order to select at will particular values of deposit hardness, strength, ductility and internal stress. Solution pH has little effect on deposit properties over the range pH 1 0-5-0, but with further increase to pH 5 -5, hardness, strength and internal stress increase sharply and ductility falls. With the pH held at 3-0, the production of soft, ductile deposits with minimum internal stress is favoured by solution temperatures of 50-60°C and a current density of 3-8 A/dm in a solution with 25% of the nickel ions provided by nickel chloride. Such deposits have a coarse-grained structure, whereas the harder and stronger deposits produced under other conditions have a finer grain size. A comprehensive study of the relationships between plating variables and deposit properties was made by the American Electroplaters Society and the results for Watts and other solutions reported... 

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