Glass tubing inside diameter

The monomer sample (ca. 1.5 mg) was sealed in a Pyrex tube (inside diameter 10 mm) in a vacuum or nitrogen atmosphere and irradiated with 60Co y rays (1.0 to 3.0 Mrad) in liquid N2 at -196 °C. The y-ray irradiation was carried out at the Japan Atomic Energy Institute at Takasaki. Solid-state postpolymerization was carried out at various temperatures (30, 25, 20, 10, 5, 0, -10, -20, and -83.6°C). The samples, polymerized for various time periods (0.5, 1, 2, 3, 6, 12, and 24 h), were dissolved in 10 ml of THF, and then the solutions were poured into 100 ml of cold acetone to separate polymer and monomer. The precipitate of the polymer was isolated on a glass filter, and the conversions were determined from the weights of polymer obtained after drying under vacuum at room temperature. 

Gel Synthesis. NIPAAm monomer (700 mM to 600 mM), polymer chains (0 mM to 100 mM), BIS (0.5 mol% to 2 mol%) and TEMED (6 pL/mL) were dissolved in water. The pregel solution was poured in a test tube containing glass capillaries (inside diameter 0.95 mm). The solution was bubbled with nitrogen, and 0.4 mg/mL APS was added to initiate the reaction. After 24 hours, the gels were removed from the capillaries and allowed to equilibrate in a large volume of MilliQ water to remove any unreacted reagents. 

Many of the analyses in the following pages are done in standard sealed tubes. This ensures that each analysis is uncontaminated by any O -enriched material from a previous run and eliminates memory effects. These tubes are made from standard Pyrex tubing (inside diameter 5 to 6 mm.) and are fitted with a breakseal (see Fig. 4a). They can be heated to about 500°C. without softening or isotopic exchange with the glass. Quartz ampoules should be used when materials have to be heated to higher temperatures. 

The most common supported tubes are those with membranes cast in place (Fig. 17). These porous tubes are made of resin-impregnated fiber glass, sintered polyolefins, and similar materials. Typical inside diameters are ca 25 mm. The tubes are most often shrouded to aid in permeate collection and reduce airborne contamination. 

A Combustion Tube of Hard Glass.—It should be about 13 mm. inside diameter, and the walls not more than i 5 mm. thick. Its length should be such that it projects at least 5 cm. (2 in.) beyond the furnace at either end. After cutting the required length, the ends of the tube are carefully heated in the flame until the sharp edges are just rounded. The tube is filled as follows. Push in a loose asbestos plug about 5 cm. (2 in.) from... 

For a small amount of material (<0.1 g), the method is simple and easy, using the basic technique of glass blowing. A piece of borosilicate glass tube, 5-6 mm inside diameter and about 30 cm long, is washed and dried in advance (Fig. A.2, (A)). First, one end of the tube is sealed with a narrow flame of a gas-oxygen torch. This is done by heating... 

The column made of glass with a 50-mm inner diameter was used as the reactor in order to observe the inside of the column. A transparent electrical resistant material was coated on the outer surface of the glass tube and it worked as an electrical heater. 

Two types of columns are used. A packed column is one filled with inert, solid particles coated with a liquid stationary phase. Standard tubing is about 0.5 cm in diameter, with lengths ranging from 1 m to 20 m however, columns for large-scale preparative work may be up to 5 cm in diameter and several meters long. Commonly used solid supports are diatomaceous earth, Teflon powder, and glass beads. The stationary liquid must be chosen on the basis of the compounds to be analyzed. A more recently developed and more widely used type of column is the open-tubular or capillary column. This is prepared by coating the inner wall of the column with the stationary liquid phase. The inside diameter of a typical capillary tube is 0.25 mm, and... 

HPLC columns are prepared from stainless steel or glass-Teflon tubing. Typical column inside diameters are 2.1, 3.2, or 4.5 mm for analytical separations and up to 30 mm for preparative applications. The length of the column can range from 5 to 100 cm, but 10 to 20 cm columns are common. 

A tube of thick-walled soft glass, about 50 cms. long, 12—13 mms. inside diameter, and walls 2—3 mms. thick. Tubes of hard potash glass with walls 2 mms. thick may also be used. The tube is carefully sealed at one end, in the manner described on p. 41, after which it is thoroughly washed and dried. 

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