Glass knives

Fused silica is slightly more brittle than borosilicate glasses and is therefore more easily fractured. Tubes up to just over 1 cm in diameter can be snapped with the fingers after scratching with a file or glass knife. Any ragged end so formed can be cleaned up with an abrasive wheel. 

Weigh liquids in a glass capillary tube 2 mm. in diameter and 7 to 8 cm. long cut with a sharp glass-knife from a drawn-out test tube. First close the tube (Fig. 35) in the middle by fusing the glass over a very small... 

If epoxy resin-embedded tissue is used, cut 2- jm-thick sections with a glass knife, mount on APES-coated slides, and dry as described in Note 2. Deplasticize the sections by immersing them in sodium eth(meth)oxide for 15 min (8). Wash the sections twice with equal parts of methanol (or IMS) and xylene, twice with methanol, for 3 min each, and rehydrate. Afterward, the same HIER and immuno-histochemical protocols are employed as in paraffin sections. 

Safety Note Making the incision for hot-spotting is best done by a special application of the glass-knife to the tube which, being difficult to describe, is illustrated in Fig. 2.15(a). Note that it is the tip of the thumb that supports the glass tube, so that if it should shatter, there is at worst a flesh wound. If the joint of the thumb were used (Fig. 2. A b)) a tendon would be at risk ... 

Fig. 1.24. Opening a sealed ampule. (a) The neck of the ampule is carefully scored using a glass knife. (b) A metal tube of larger diameter than the ampule neck is placed over the neck. Inert gas flowing through the metal tube will minimize exposure of the ampule contents to air once the neck is broken. A quick jerk is then applied to the metal tube, which snaps the neck off (c) at the score.

Note. (1) Methyl bromide (b.p. 4.5 °C) is supplied in sealed vials. The vial must be thoroughly cooled in an ice-salt bath before any attempt is made to open it. It is advisable to wear a face mask and thick gloves during the operation. Wrap a cloth around the vial and score around the neck with a glass-knife. Place several layers of cloth around the scored neck and break off the end of the neck. 

We know that diamond can scratch glass, but so can hard metals such as the hardened steel of a file or a tungsten-carbide glass knife. A beaker that is slid or... 

The brominated sticks are embedded in Spurr epoxy resin (Spurr 1969) and sectioned with a diamond knife or glass knife mounted on an ultramicrotome to give cross sections of 0.15//m thickness for TEM-EDXA or 0.5//m thickness for SEM-EDXA. The sections are then placed on a carbon-coated collodion film on the specimen support grid. The specimens are carbon-coated again to avoid charging. 

After distillation is complete the apparatus is left to cool, and the purified material recovered by cutting up the apparatus into three sections using a glass knife. 

Use the 30 cm lengths of tube, the ends of which are already fused. Make a small mark at the centre of each tube with a glass-marking pencil, or, if preferred, with a glass knife or file. Now make two other similar marks on the tubes, one... 

The rest of the tools in frequent use are a small new triangular file, or, better, a hardened steel (glass) knife for cutting purposes, and a piece of arc-light carbon with... 

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