Fine grained

Deltaic (distributary channel) Isolated or stacked channels usually with fine grained sands. May or may not be in communication Good producers permeabilities of 500-5000mD. Insufficient communication between channels may require infill wells in late stage of development... 

If compaction occurs as a result of production careful monitoring is required. The Ekofisk Field in the Norwegian North Sea made headlines when, as a result of hydrocarbon production, the pores of the fine-grained carbonate reservoir collapsed and the platforms on the seabed started to sink. The situation was later remedied by inserting steel sections into the platform legs. Compaction effects are also an issue in the Groningen gas field in Holland where subsidence in the order of one meter is expected at the surface. 

In 1990, ASTM E07-01 started work on a revision of E94. The proposed criteria for film classification used graininess and gradient to produce an index which represented quality. In early work it was discovered that a fine grained film was possible with low contrast which produced the same index as a fine grained film with high contrast. 

Gd converter can be used. Both techniques were studied and compared with the common direct neutron imaging with Gd metal converter (0.1mm thick) and single coated fine grained radiographic film, exposed in a vacuum cassette. The unprotected IP ( TR type ) in combination with the Gd metal converter were also exposed in a vacuum cassette. Our experience can summarized as follows ... 

It has been found that the contrast in film density caused by very small local variations in mass density of the concrete is considerable, e g. S D = 0.12 for a 6 mm diameter hole in a 250 mm thick concrete beam. The image quality provided by fine-grained films (Agfa Gaevert D7) was sufficient to distinguish the thin walls of a pre-stressing duct in a 750 mm thick concrete bridge slab. 

Finaplix Finaprene Finasteride [98319-26-7] Finazoline Fine arts Fine chemicals Fine-coarse difference Fine-grain sugar... 

Sandstone. Sandstone wheels were once quarried extensively for farm and industrial use, and special grades of stone for precision honing, sharpening, and lapping are a small but important portion of today s abrasive industry. Production of honing and sharpening stones from deposits of dense, fine grain sandstone in Arkansas account for 76% of the value (about 2 million in 1987) and 88% of the total quantity of such stones in the United States (4). 

Tripoli. TripoH [1317-95-9] is a fine grained, porous, decomposed siHceous rock produced mainly in Arkansas, Illinois, and Oklahoma. It is widely used for polishing and buffing metals, lacquer finishing, and plated products. Since tripoH particles are rounded, not sharp, it has a mild abrasive action particularly suited for polishing. TripoH is also used in toothpastes, in jewelry polishing, and as filler in paints, plastics, and mbber. Rottenstone and amorphous siHca are similar to tripoH and find the same uses. In 1987 the abrasive use of tripoH in the United States totaled 26.6 million tons and was valued at about 3.1 million however, the portion used as a filler totaled 71.1 million tons and had a value of almost 10 million (4). 

The Fe, Co, and Ni deposits are extremely fine grained at high current density and pH. Electroless nickel, cobalt, and nickel—cobalt alloy plating from fluoroborate-containing baths yields a deposit of superior corrosion resistance, low stress, and excellent hardenabiUty (114). Lead is plated alone or ia combination with tin, iadium, and antimony (115). Sound iasulators are made as lead—plastic laminates by electrolyticaHy coating Pb from a fluoroborate bath to 0.5 mm on a copper-coated nylon or polypropylene film (116) (see Insulation, acoustic). Steel plates can be simultaneously electrocoated with lead and poly(tetrafluoroethylene) (117). Solder is plated ia solutioas containing Pb(Bp4)2 and Sn(Bp4)2 thus the lustrous solder-plated object is coated with a Pb—Sn alloy (118). 

The development of the principles of nucleation and growth eady in the twentieth century (2) ultimately led to the discovery that certain nucleating agents can induce a glass to crystallize with a fine-grained, highly uniform microstmcture that offers unique physical properties (3). The first commercial glass-ceramic products were missile nose cones and cookware. 

By using nucleants, fine-grained stmctures, such as that shown in Figure 4b, can be produced in cast alloys independent of the antimony content. The molten metal must be kept at a temperature high enough to assure complete solubiUty of the nucleants prior to casting the alloy. In the United States primarily copper and sulfur are used as nucleants in Europe and Asia selenium is used. At very low (1.0—1.6 wt %) antimony contents selenium is used exclusively. 

Cast lead—calcium—tin alloys usually contain 0.06—0.11 wt % calcium and 0.3 wt % tin. These have excellent fluidity, harden rapidly, have a fine grain stmcture, and are resistant to corrosion. Table 4 Hsts the mechanical properties of cast lead—calcium—tin alloys and other alloys. 

Wrought or extmded lead—teUurium (0.035—0.10 wt %) aUoys produce extremely fine grains. The binary aUoy is, however, susceptible to recrysta11i2ation. The addition of copper or sUver reduces grain growth and retains the fine grain si2e. Because teUurium is a poison for sealed lead—acid batteries, the teUurium content of lead and lead aUoys used for such purposes is usuaUy restricted to less than 1 ppm. 

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. 

Compact limestone is a general term depicting a dense, fine-grained, homogeneous, usually hard type of stone. 

Filter Beds. The sprinkling filter beds of sewage plants are composed of closely screened mineral aggregate of 38—64 mm or 51—76 mm that meet a severe soundness test. Much of this requirement is suppHed by dense, fine-grained, hard limestone and dolomite. 

Because the time at high temperature is much less, austenite is produced, which is chemically inhomogeneous especially with undissolved carbides, and has a fine grain crystal size. The formation of the hard martensite requites more rapid cooling than for conventional hardening. Thus case hardening by heat treatment intrinsically requites that the surface region to be hardened be relatively thin and cooled rapidly. 

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