Round discs

Native American artists created small round discs of shell that were drilled in the center and used as beads or bead separators. These are called heishi, a word that originally meant shell. A shell is first cut or broken into small flat tiles, and a hole is drilled in the center of each. They are then strung tightly together on wire or cord. The entire strand is then ground against a stone or a turning wheel until the discs are round. Modem heishi are made in many different materials and are often produced by machine. 

Similar to the results described after selection for freeze thaw resistance, there were reductions in microbial diversity and abundance after ice affinity selection. A total of 19 isolates were recovered from the three locations, but many of these were duplicated, so that only five distinct genera were identified by DNA sequencing. Included in this group were five isolates of Chryseobacterium sp. Again, there was some evidence of IR inhibition activity as seen with the Chryseobacterium sp. strain obtained by freeze-thaw resistance selection. When ice crystals were formed in the presence of this bacterium, the morphology was changed from a round disc-like shape seen with buffer solutions, culture media, or E. coli (Figure 5) to an oval-shaped crystal (not shown). 

The 4 cm round disc at the left front is the actual hot stage of the apparatus. The magnifying glass on the holder immediately to the left of the hot stage is used to magnify the crystals, so you can more easily note small crystalline changes. 

The flat-plate type of thermal conductivity apparatus appeared to be best suited for the planned program for the following reasons (1) the test sample can be a small, easily assembled, round disc of different diameters (2) the sample can be of any thickness, between broad limits, and still be in contact with both boundaries and (3) a mechanical load can be applied to the sample under test. 

Stud buttons are metal round discs pinched through the fabric. They are often found on clothing, in particular on denim pieces such as pants and jackets. They are more securely fastened to the material. As they rely on a metal rivet attached securely to the fabric, stud buttons are difficult to remove without compromising the fabric s integrity. They are made of two couples the male stud couple and the female stud couple. Each couple has one front (or top) and rear (or bottom) side (the fabric goes in the middle). 

In operation a screen pack is backed up by a breaker plate that has a number of passages, usually many round holes ranging from i to in. in diameter. One side of the plate is recessed to accommodate round discs of wire screen cloth, which make up the screen pack (usually 40- to 100-mesh screen). Pressure controls should be used on both sides of the breaker plate to ensure that the pressure on the melt stays within the required limits. Based on the processing requirements, manual to highly sophisticated screen changers are used. 

After casting, the bar, block, or round disc is cooled to room temperature in the glassy condition. This process consists of two phases (Fig. 4.16) ... 

The turbine mixing heads consisted of alternate sets of fixed and moving teeth made by machining slots around the periphery of round discs externally for the rotor and internally for the stator. The rotor formed a screw extension and the stator a matching barrel extension. 

Thallus crustose, foliose, or fruticose. Apothecia usually solitary with open round discs and a clearly developed rarely absent radiate amphi-thecium in most species. Paraphyses most often with thickened knoblike tips. Asci normally 1+ blue and thick-walled. Spores polymorphous. On various substrates in all zones. Most species are lichenized, some are parasitic on lichens, and a very few are saprophytic. 

Dough Resting, Cutting and Forming Hand-Shaping or Roller Pins Round Discs (1.3-3 mm Thick, 20-25 cm Diameter) ... 

To begin the first meeting, the physicists made two sketches of the disc diyer machine on the whiteboard (see Figure 6) that visualized mechanical features physical processes and production data parameters. The upper sketch illustrates a crude three-dimensional representation of the machine. The physicists understood the internal physical construction of the dryer to be a big cavity containing rotating discs product inlet outlet and the internal distribution of product. Beneath the 3D sketch, we see a two dimensional sketch where the round discs are lepiesented with lines separating the dryer s interior into discrete volumes. The physicists attached... 

Shafting takes on several forms to match the various rotor construction methods. Obviously, for the solid rotor, the shaft is a part of the overall rotor. For the shrunk-on discs, the shaft is a continuous member, carrying the discs in the center section. Concentricity of all turns and good control on the roundness of the shaft are critical, if a balanced, smooth running compressor is to result. 

To make the seal one of the tubes is clamped vertically and the preoxidized disc is placed centrally upon the flare of this tube. Working round the tube with a hand torch the glass is softened and the disc fused into place. With the seal still hot, the tube is removed from the clamp and, rotating by hand in a bench flame, the second glass flare... 

Morphologies of synthetic hematite include plates and discs, rods, spindles, spheres, ellipsoids, double ellipsoids, rhombohedra, stars, cubes and peanuts. In the absence of additives, hexagonal plates, which are often rounded, and rhombohedra predominate. Each morphology can be obtained by more than one synthesis route. Two common ways of producing idiomorphic hematite crystals in aqueous systems... 

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