Apparatus and glassware

Glass fibre filters Usually 14 cm diameter (eg., Whatman GF/C, Schleicher Schtlll No. 6, Gelman AE), kiln-fired 4 h at 450 °C. 

Rotary evaporator. With solvent trap (Fig. 18-2) and 5 A molecular sieve at the air inlet. 

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If all the criteria listed above are not met, check solvents, reagents, apparatus and glassware to locate and eliminate the source of contamination before any more samples are extracted and before any positive samples are reextracted. 

The author wishes to express his special gratitude to Prof. Dr. habil. Kl. Wetzel for his interest in the book, his valuable suggestions and constant support. He also wishes to thank Dr. H. Stage and E. Giebeler for the numerous helpful comments they have made. Further his thanks are due to the various manufacturers of laboratory apparatus and glassware who have provided him with prospectuses and... 

Use caution and the proper equipment when handling hot apparatus or glassware. Hot glass looks the same as cool glass. 

Steyermark, A., and H. K. Albert Report on Recommended Specifications for Microchemical Apparatus, Volumetric Glassware, Microliter Pipets. Anal. Chem. 30, 1702 (1958). 

Clean all the glassware and other apparatus, and dry in an 120°C oven for at least 4 h before use. Assemble glassware while still hot. 

II.4 SEMIMICRO APPARATUS AND SEMIMICRO ANALYTICAL OPERATIONS The essential technique of semimicro analysis does not differ very greatly from that of macro analysis. Since volumes of the order of 1 ml are dealt with, the scale of the apparatus is reduced it may be said at once that as soon as the simple technique has been acquired and mastered, the student will find it just as easy to manipulate these small volumes and quantities as to work with larger volumes and quantities in ordinary test-tubes (150 x20 mm) and related apparatus. The various operations occupy less time and the consumption of chemicals and glassware is reduced considerably these two factors are of great importance when time and money are limited. Particular care must be directed to having both the apparatus and the working bench scrupulously clean. 

It is required that all glassware be rinsed or preextracted with solvent immediately befor use. The SDS apparatus and continuous liquid-liquid extractors must be preextracted for approximately three hours immediately prior to use. The pooled waste solvent for a set of extractions may be concentrated and analyzed as a method of demonstrating that the glassware was flee of contamination. 

Volumetric Apparatus. Volumetric glassware is of three principal kinds volumetric 8 asks, pipettes, and burettes see Fig. 1. 

Glassware for repair or modification should be cleaned and dried by the user. He knows best what has been in the apparatus and what steps to take in cleaning it. 

Use Laboratory and pharmaceutical glassware and apparatus, electrochemical equipment, fiber manufacture, domestic ovenware apparatus, and equipment for many processes. 

Great care should be taken to ensure that all apparatus and chemicals are sterile and free from RNase contamination. Glassware should be incubated at above 150°C for at least 6 h. All solutions not containing amines should be treated with diethyl-pyrocarbonate (DEPC) and autoclaved. If solutions contain amines (Tris), RNase-free chemicals should be added to DEPC-treated distilled water. Gloves should be worn at all times and changed frequently. 

The tubing and glassware should then be rinsed with copious amounts of water until the chlorine odor has dissipated. The apparatus can be stored for later use. 

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