Heat-resisting glass

Temperature, °C Soft glass Heat-resistant glass... 

Infusion Boiling water (150 250 ml) is poured over the prescribed amount of drug in a heat-resistant glass or porcelain vessel, which is then covered if necessary, the contents are stirred occasionally. If no other indication is given, the contents arc strained after 5 -10 min. This method can be used for most leaves, flowers, and herbs and also for many correspondingly comminuted barks and roots. 

Heat resistant glasses (e.g. Pyrex), glass wool, fibre glass 26% (60%)... 

Phoenix, also, is a borosilicate glass made by the British Heat Resisting Glass Co. The linear expansion coefficient (50-450°Q is 3-24 X 10" . Tubing and rod are supplied in a wide range of sizes. The tubing is made with either standard wall or heavy wall. 

A combustion tube of heat-resistant glass having a constriction at one end (length without the constricted part 55 cm., external diameter 12 mm., length of the constricted part 3 cm., external diameter 3-3-5 mm., internal diameter 2 mm.). 

If halogen and sulphur have to be determined simultaneously in one substance, first determine the halogen by the Carius method. Collect the filtrate from the silver halide in a carefully cleaned filter flask, transfer to a beaker of heat-resistant glass, dilute to 120-150 c.c., and precipitate the sulphuric acid from the boiling solution with 1 per cent barium nitrate solution absolutely free from halogen. 

PE general purpose, ammonia free PE heat resistant, glass fibre reinforced PE impact resistant, cotton filled PE mica filled PerEluoroAlkoxy PolyGlycolic Acid PolyHydroxyAlkanoate PolyHydroxyButyrate... 

When mixed with sodium carbonate (soda ash) and calcium carbonate (powdered limestone) and heated until the mixture melts, silica (sand) forms glass when cooled. Glass of all types has near limitless uses. One example is Pyrex, which is a special heat-resistant glass that is manufactured by adding boron oxide to the standard mixture of silica, soda ash, and limestone. Special glass used to make eyewear adds potassium oxide to the above standard mixture. 

The sampling tube is made of heat-resistant glass and one end is drawn out to form a capillary injection needle (Figure 1). The other end of the tube is a glass cone (Quickfit 7/16) which allows a clean connection, without any gasket, to the vacuum pump or gas supply. The adsorbent, 0.3 g of TENAX TA, 35-60 mesh, is kept between plugs of glass wool. 

Mercury diffusion pumps are normally constructed from quartz or heat-resistant glass and are therefore a possible source of hazard should they Sreak, especially whilst they are hot. However, during over 40 years of working with such pumps, the author has neither experienced nor heard of such an accident. The major real disadvantage of mercury pumps is the relatively high vapour pressure of mercury at room temperature (ca. 10 Torr), which makes its necesssary to ensure that the cold traps prevent efficiently the mercury vapour from diffusing forward into the line. 

Figure 3.38 This glassware is made from Pyrex, a heat-resistant glass.

Distillation Flask A 200-mL round-bottom distilling flask of heat-resistant glass is preferred when sufficient sample (in excess of 100 mL) is available for the test. If a sample of less than 100 mL must be used, a smaller flask having a capacity of at least double the volume of the liquid taken may be employed. The 200-mL flask has a total length of 17 to 19 cm, and the inside diameter of the neck is 20 to 22 mm. Attached about midway on the neck, approximately 12 cm from the bottom of the flask, is a side arm 10 to 12.7 cm long and 5 mm in internal diameter, which forms an angle of 70° to 75° with the lower portion of the neck. 

Container Use a heat-resistant glass vessel, such as an 800-mL low-form Griffin beaker, not less than 85 mm in diameter and not less than 127 mm in depth from the bottom of the flare. 

Cost of heat-resistant glass pipe and fittings. 

Gas Chromatographic Columns. Two heat-resistant glass columns, A and B, % inch nominal o.d. (1.5 mm. i.d., 3 mm. o.d.) and 5 feet long, are used. Column A is packed with 60-70 mesh acid-washed Chromosorb G, coated by weight with 0.15% Carbowax 20M (a polyethylene glycol) and with 1.5% DC 200 (12,500 centistokes) silicone fluid Column B is packed with 60-70 mesh acid-washed Chromosorb G, coated by weight with 0.10% Carbowax 20M and with 1.0% QF-1 fluorosilicone (also called FS 1265). 

The flow pattern in the secondaiy combustion chamber was measured with a Laser Doppler Velocimeter (LDV). The burner was equipped with a heat resistant glass cover to give the laser diagnostic access to the combustion process. To make the flow patterns visible, magnesia powder particles were added to the primary and secondary... 

Mentally note whenever the HPS and metal halide lights are in use and you have a water sprayer or hose in your hand. A drop of water hitting a bulb will cause it to explode H this happens, turn off the lights immediately and leave the room until the air is evacuated. Sheets of heat resistant glass shields are sold with HID lights. They should be cleaned once every few weeks. Never touch a bulb while it is on a bulb must be cool before it is tended to. 

Heat-resistant glasses of the system Na20—B2O3— Si02... 

Glass containers used for heating should be made of heat-resistant glass. 

Absorption towei. Heat-resistant glass inside diameter, 4.094 inches 4 feet long. Column cross section, 0.09152 sq. foot. Packed with 1/4-inch Intalox saddles... 

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