Fire polishing glass

To learn basic glassworking by bending and fire-polishing glass tubing. 

Sterile glass rod—Place a fire-polished glass rod in a capped test tube and autoclave (20 min at 105 to 110°C). 

Transfer organ of Corti with a fire-polished glass Pasteur pipette into a petri dish containing culturing media and cover-slips coated with Cell-Tak (see Table 3 and Remark 1). If necessary, cut the organ of Corti into pieces with forceps and gently press pieces down on coverslips. 

These so-called solventless BLMs [15-17] can also be formed on the end of fire-polished glass pipettes with a small tip area (tip diameter 1 fim) [19], The lipid solution in n-hexane is applied to the outside of the shaft of a pipette which is oriented vertically and penetrates the surface of the aqueous solution. The drop runs down the shaft and spreads at the air/water interface. A short exposure of the pipette tip to air and subsequent reimmersion through the lipid layer leads to the formation of a BLM at the tip of the pipette. This technique has been used to obtain a digital sensor, where off/on signals can be obtained when a single ion channel protein is reconstituted [20]. 

The Hartford-Empire 28 is a press-and-blow machine used to make articles such as drinking glasses (tumblers). It uses paste molds and the ware is rotated to avoid the mold seams jars with screw threads cannot be produced. The product leaves the machine as an almost closed, hoUow object and is finished by severing and fire-polishing with a bum-off machine. 

The apparatus consists of a 100-ml distilling flask equipped with a dropping funnel and arranged for distillation through an efficient condenser. The condenser is connected to two receiving flasks in series, the second of which contains 20-30 ml of ether. The inlet tube of the second receiver dips below the surface of the ether and both receivers are cooled in ice baths. All connections in the setup are made with bored cork stoppers and all glass tubing is fire polished (Fig. 17.1). 

Salt that sticks to the sides of the Erlenmeyer flask may be loosened with a piece of 10-mm. glass tubing that has not been fire-polished. 

To fix on the window as shown in Figure 75,7, a bulb is blown in the capillary, the top of the bulb is blown out to a bubble, knocked off, and the end remaining is fire-polished and finally ground flat. The tube can be filled with gas through a side arm joined to one of the electrode chambers the spectrum tube may be sealed off, or provided with a stopcock. TIk capillary tube in Figure 75, II, is sealed to the glass at one end only of the capillary. To do this, the capillary is joined to a wider tube, which is cut off and flared out to make the... 

Evaporation of an ethereal solution of hydrogen peroxide gave a residue of which a drop on a platinum spatula exploded weakly on exposure to flame. When the sample (1-2 g) was stirred with a glass rod (not fire polished), an extremely violent detonation occurred. 

The checkers added the slurry via a large, medium-bore, glass funnel with fire-polished edges. In one of three runs a small, sharp report was heard, apparently from a source above the liquid in the beaker the yield of biphenylene in this run did not differ significantly from that obtained in the other runs. 

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