Slitting. Cutting

For high efficiency, coating usually is performed over a width of more than a meter. The tape rolls are obtained by cutting the web into strips with a width of a few millimeters up to several centimeters. Four methods are applied (Fig. 18). 

Shear cutting (Fig. 18 A) is effected between a rotating knife and a roller edge and results in tapes with smoothly cut edges. This method has the highest precision, but the width of the tape rolls cannot readily be changed. It is used for most rigid-film tapes and double-sided tapes. 

In log cutting (Fig. 18 C) the coated web is wound into rolls or logs in full width and in the desired length of the tape rolls. Subsequently, these logs are sliced by a rotating knife, which is moved transversally between slices to match the width of the tape rolls. As the transverse location can be adjusted deliberately by a computer, this process allows the complete customization of the width of the tape rolls. 

In razor blade cutting (Fig. 18 D) the web is cut by parallel razor blades. The edges are cut very smoothly. Due to the lower stif iess of the blades the precision is lower than with the other methods. It is preferred for, e.g., carton-sealing tapes. 

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Effect of the Razor Slits Cut Parallel to the Extension Direction on Fracture. 529... 

In a 250-00. Erlenmeyer flask provided with a two-holed stopper which has a slit cut in one edge to serve as an air vent and which holds a thermometer, the bulb of which reaches almost to the bottom of the flask, is placed 31.5 g. (0.5 mole) of anhydrous nitric acid (Note 1). The flask is cooled below io° in ice-water, and 51 g. (0.5 mole) of acetic anhydride (Note 2) is slowly added from a buret through the second hole in the stopper in portions of about 0.5 cc. at a time. The temperature of the reaction mixture is never allowed to rise above io° (Note 3). After about 5 cc. of the acetic anhydride has been added the reaction becomes less violent, and larger portions, increasing gradually from 1 to 5 cc., may be introduced at a time with constant shaking. After all the acetic anhydride has been added, the stopper and the thermometer are removed. The neck of the flask is wiped clean with a towel, and the flask is then covered with an inverted beaker and allowed to come up to room temperature in the original ice bath (Note 4). 

Slide the length of magnesium ribbon into the slit cut in the craft stick, as shown. 

Coating the point witii potassium cyanide is the tricky part. Qyanide has to be bound witii a substance which will keep it hard and make it penetrate the fledi. I find tiie best sdMtance to be lePages or Ross mucilage bought at any store in the school supplies section. The rubber applicator should have its slit cut wider so the miidlage can be squeezed out a drop at a time. 

In practice, the endoscope is threaded into a channel, perhaps the nose, mouth, anus, vein or abdominal cavity through either a natural opening of the body or a small slit cut through tissue. The endoscope has been instrumental in allowing surgical procedures to proceed without large incisions (arthroscopic). 

The first successful active immunization is ascribed to Edward Jenner, an English country physician who in the I790 s tested a belief common among local dairymaids—that prior exposure to a mild cowpox infection of the udder on a cow provided immunization against smallpox. Beginning in 1796, Jenner carried out tests in which he intentionally infected people by applying cowpox lymph obtained from a lesion to small slits cut in the arms of volunteers. During a subsequent epidemic, none of the inoculated individuals developed smallpox. Jenner called the practice vaccination, from vacca, Latin for cow. 

Plastic pipes come in various configurations. Most of them are corrugated with slits cut at intervals to allow water to enter easily. They are usually supplied in 200 metre rolls which are easily transported. Various diameter sizes are available, e.g. 60 or 80 mm for laterals, 100, 125, 150 or 250 mm for mains. 

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