Knife casting

Figure 3.2 Scheme of a theoretical gradient of two constituents of solution A and solution B. Solution A flows into solution B as both valves are opened. A gradient mixture of B to A is then flowed onto a glass plate for knife casting. 

Fig. 11. Schematic of Loeb-Sourirajan membrane casting machine used to prepare reverse osmosis or ultrafiltration membranes. A knife and trough is used to coat the casting solution onto a moving fabric or polyester web which enters the water-filled gel tank. After the membrane has formed, it is washed...

Putties are heavy-bodied pastes of high pigment content that are applied by knife for rough filling of deep indentations, more especially in rough castings. 

Selective form of iron corrosion, primarily in gray cast iron but also less commonly in nodular cast iron, whereby the (anodic) iron matrix converts to iron oxide while the (cathodic) graphite remains intact. The casting retains it shape but loses all strength and can be cut with a knife. 

The coatings were applied to one side of a steel substrate by means of a spray gun for the lower viscosity coatings, or by doctor blading with an adjustable Gardner knife for the higher viscosity materials. A casting technique was also used in which a known volume of the coating material was poured into a known area defined by heavy tape and was allowed to spread while on a level surface. 

Asymmetric Membrane Preparation. The preparation of the as5Tnmetric membranes was done in a fashion similar to the "classical" technique referred to below, although the casting solutions often deviated from the "classical" formulations. In all cases, a solution of polymer plus at least two other components was cast on a glass plate with a doctor s knife set at a thickness of 15 mils (0.381 mm). After a brief evaporation period the membrane was gelled in a non-solvent bath. Finally, the membrane was thoroughly washed in distilled, deionized water. 

Although it involves a knife rather than a gun, this case illustrates two continuing themes that will be applied to firearm regulation (1) the question of whether the right to bear arms is collective or individual, and (2) the application of the police power of the state to the types of weapons people may have and the manner in which they may be carried. This case cast an early vote for the collective position and upheld the state s police power. 

The calf antibiotic and sulfa test (CAST), the fast antimicrobial screen test (FAST), and the swab test on premises (STOP) are all bacterial inhibition tests developed at the US Department of Agriculture Food Safety and Inspection Services to screen kidneys for antimicrobial drug residues at slaughter (97-101). For CAST and FAST, an incision is made with a knife, whereas for STOP the tissue is macerated with the shaft of the swab. For all three tests, cotton swabs are inserted into kidney tissue to soak up fluids. Swabs are then incubated on inoculated medium with a disc containing an antibiotic standard used to monitor the viability of the organism and its growth inhibition. 

Examination of Cast Film. The film can now be examined both before and after stripping from foil. A simple test was devised to determined the transition point from liquid to nonliquid state. A palette knife was drawn along the foil from the end where some of the plastisol was still liquid. Plastisol flowed easily in front of the knife until it came to a point where the plastisol was no longer spreadable. At this point, which was sharply defined, it was impossible to push the blade further. The temperature at which this occurs has been called the liquid/solid transition point (Figure 5). 

Solvent Casting. The polymer is mixed with the plasticizer in the required proportion and dissolved in methylene chloride to form a 10% solution. Films are cast from this solution on a glass plate using a Gardner knife. The films are allowed to dry overnight at room temperature, and any residual solvent is removed by heating for 10 hours in an oven at 110°C. The thickness of the dry film should be about 100 n. 

A mixture of 15 gms. of phthalic anhydride and 22 gins, of resorcinol is ground in a mortar. It is then transferred to a nickel or cast-iron vessel, and heated in an oil bath to 180°. At this temperature 7 gms. of powdered fused zinc chloride (see p. 509) are added, with stirring, during the course of 10 minutes. The temperature is raised to 210°, and maintained at this point until the liquid, which gradually thickens, becomes solid, for which 1—2 hours are required. The cold melt is removed from the vessel with a knife or chisel, powdered, and boiled 10 minutes with 200 c.cs. of water and 10 c.cs. of cone, hydrochloric acid. This treatment eauses the solution of zinc oxide and basic zinc chloride. The fluorescein is filtered off, washed with water until the filtrate no longer shows an acid reaction it is dried on a water bath. 

Another microscopic technique is to freeze the specimen and then fracture it with a knife. A knife cutting through the frozen specimen splits the membrane down the middle, exposing the inside of the bilayer (fig. 17.13a). If the Davson-Danielli model for membrane structure were correct, the two exposed surfaces would be featureless. However, electron micrographs of metallic casts of such samples reveal surfaces studded with particles of various sizes (fig. 17.13(f)- Additional studies indicate that these particles are proteins that are deeply embedded in the membrane. The particles seen on the inner and outer leaflets of the bilayer usually differ in size and distribution because of an asymmetrical disposition of the proteins across the bilayer. 

The electron micrographs of the various ERL-4221-CTBN systems were prepared with the osmium tetroxide technique (3). The castings were stained by reaction with osmium tetroxide vapors for 24 hours. Ultrathin specimens, approximately 1000 A thick, were cut with the Reichert OMU2, ultramicrotome equipped with a diamond knife and were stained again for one hour. The osmium tetroxide selectivity stained the rubber phase, while the epoxy remained unaffected, revealing many structural features in the polyphase systems with excellent contrast and... 

Paper pencil small (3-x-4-in.) cardboard box with lid plaster of Paris or casting plaster water iron skimmer ladle pewter in sheet or ingot form wire (stove pipe) pliers carving tools (simple knife nail file pencil old dental tools or anything that will carve plaster) wire cutters propane torch fireproof surface (casting container of sand) steel wool jeweler s saw and blades files X-ACTO knife C-clamp leaves. 

Figure 3.1 A typical hand-casting knife. (Courtesy of Paul N. Gardner Company, Inc.,...

Figure 27 Synthetic plastics imitated successfully exclusive natural materials a Bakelite ash tray with built-in match holder and striker in marble Roanoid, with marbleized, brass-tipped cigarette holder, 1930s. Carvacraft desk set in amber cast phenolic, 1948-51 double inkwell, notepad holder, blotter and paper knife with clear acrylic blade. Smiths Sectric alarm clock with marbleized urea-formaldehyde case, 1932. Ardath Tobacco cigarette box in ivory and black urea-formaldehyde with lid moulded to simulate a classical relief, 1935. Propelling pencil with black and orange mottle typical of vulcanite, 1930s (Photo Stephen Brayne, Collection Sylvia Katz)...

Since the inception of the era of modem ceramics, usually defined as starting in the late 1940s, there have been many advances in ceramics processing technology. One of the most prolific advances in terms of commercial use has been the development and implementation of tape casting, also referred to as knife coating... 

The selective corrosion of cast iron (graphitization), the preferential corrosion of the steel welding (grooving corrosion), sensitization and knife line attack of welded stainless steels are typical examples of corrosion influenced by metallurgical parameters. 

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