GLASS-WORKING EQUIPMENT

Trivial burns are sometimes produced by the accidental handling of hot glass. These may be smeared with vaseline or skin cream and covered with clean or preferably sterile linen. Blisters should not be broken. Tannic acid jelly is not recommended. 

Before any glass-working is started care should be taken to make sure that the glass is thoroughly cleaned. This cleaning is necessary for 

We find that tubing in the range of 15-30 mm diameter (approximately) can be broken by a variation of the above method The tubing is scratched fairly strongly, and placed, with the scratch uppermost, so that it rests on a copper wire, about 3 mm diameter, which is opposite to the scratch and parallel to it. The scratch is moistened. 

A square end is more easily obtained by the hot wire method. The tubing is first scratched all the way round. This may be done by 

It is often easier to wind a spiral on a mandrel or former of carbon, metal tubing or glass tubing wrapped with asbestos paper. A right-angle bend is made in the tube to give a short portion at the end which 

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In this Chapter we describe the construction of various pieces of apparatus by the methods of glass-working already described. All the apparatus mentioned below can be made by quite simple methods and without the use of the expensive items of glass-working equipment such as lathes, ovens, various wheels and so on. Many pieces of complex-looking apparatus are made merely by a succession of simple operations. 

Large glass-working laboratories may be equipped with a glasscutting machine. This usually consists of a high-speed, power-driven, fine abrasive wheel, or, better, a steel wheel in whose perimeter are embedded fine diamond particles. A lubricant—water, or water and cutting oil emulsion—is played on to the faces of the wheel from jets on either side. The glass to be cut is held on a movable steel table mounted on rollers. 

Glass-working shops that are called upon to make large or intricate apparatus should be equipped with an annealing oven. With some ingenuity a home-made one can be built using Nichrome wire and fire-brick. 

The electrochemical behavior of malonyl-a-aminopyridines 661 was investigated by Gullu et al. in acetonitrile or a mixture of trifluoroacetic acid and dichloromethane containing tetrabutylammonium tetrafluoro-borate or triethylammonium trifluoroacetate in a water-jacketed, two-compartment glass cell equipped with a platinum disk anode at 1.50 V (Ag/ Ag+) and a carbon-rod secondary electrode (91T675). Controlled potential anodic oxidation of 661 afforded labile coupled carboxylic acids 662 (R2 = COOH), which easily decarboxylated to compounds 662 (R2 = H) under the work-up conditions. Sometimes, the carboxylic acid 662 (R2 = COOH) could be isolated or when the reaction mixture was treated with methanol, methyl ester 662 (R = H, R1 = Bu, R2 = COOMe) was obtained in 40% yield. 

A large selection of gases with an impurity content of only 1 in 10s or less is available in glass containers, equipped with break-off seals. These assayed reagents are satisfactory for routine work however, for adsorption studies at high pressure or long times, even minute amounts of contamination may obscure the validity of the experiment. Further purification in the system itself may therefore be necessary. 

The experiment is carried out using a glass column suitable for high-pressure work, equipped with a protective shield. Reconunended is the Waters AP-1 10-mm X 100-mm glass column from Waters Corporation, part number WAT021901. The column is packed with a fully porous silica. A particle size of 30/im is recommended. This keeps the packing procedure simple, maintains a low operating pressure, but still allows you to obtain narrow bands. The mobile phase is a mixture of 59% toluene and 41% methanol. An HPLC instrument is required for the demonstration. 

Koshlyak LL (1960) A method of evaluating the effectiveness of clay-working equipment. J Glass Ceram 17,1,12/1 pp 29-32 doi 10.1007/BF00838663,... 

Whether you are performing the cutting operation or assisting, wear appropriate personal protective equipment a hard hat, face shield, safety glasses, work gloves, steel-toe safety shoes, and if necessary, hearing protection and a respirator. 

Coverahs or other full-body clothing should be worn when working with lead ahoys and properly laundered after use. Hard hats, safety glasses, safety boots, and other safety equipment should be worn as appropriate for the industrial environment where the lead ahoys are used. Hands, face, neck, and arms should be washed before eating or smoking. 

Other dimer acid markets include intermediates for nitriles, amines and diisocyanates. Dimers are also used in polyurethanes, in corrosion inhibition uses other than for downweU equipment, as a "mildness" additive for metal-working lubricants, and in fiber glass manufacture. 

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