Glassware applications

A suitable functional group is assayed in the same sample. In general chemistry and many polymer applications, this is merely the titration of acid groups with a base, or vice versa. Note that only volumetric glassware and a method for end point determination are required to do this. 

Sample Collection and Enzyme Stability. Serum samples are collected with chemically clean, sterile glassware. Blood is allowed to clot at room temperature, the clot is gently separated from the test tube with an applicator stick, and the blood is centrifuged for 10 minutes at 1,000 g. If the red cells are known to contain the enzymes whose activity is being measured, as in the case of LD, even slightly hemolyzed serums must be discarded. When acid phosphatase is to be measured, the serum should be placed immediately in ice and processed as soon as possible, or it should be acidified by the addition of a small amount of sodium citrate. Anticoagulants such as EDTA, fluoride and oxalate inhibit some serum enzymes. However, heparin activates serum lipoprotein lipase. 

In this paper we review the techniques and applications of microwave irradiation in cycloaddition reactions. This mode ofheating requires not only appropriate micro-wave equipment and glassware, but also a new experimental outlook. A special section will focus on modifications of chemo-, regio- and stereoselectivity which result from use of microwaves, and possible explanations of this behavior will be given. 

Describe individual items of equipment and how they are connected in sufficient detail to enable unambiguous set-up. List minimum performance requirements and verification requirements, cross-referenced to the calibration section and any relevant instrument manuals. Number for later reference. For glassware, include grade where applicable (bear in mind that use of a particular grade may require justification and that proof of compliance may be required). Include environmental requirements (fume cupboards, etc.). 

Reactions with bis(dialkylainino)difluoro-/l.4 -sulfanes can be performed in normal glassware under anhydrous conditions. Caution in the presence of moisture hydrolysis takes place liberating hydrogen fluoride. Bis(dialkylamino)difluoro-24 -sulfanes are less reactive fluorinating reagents than (dialkylamino)trifluoro-24 -sulfanes. This fact coupled with their lengthier syntheses and their noncommercial availability has limited their application. 

Glassware that has bends and/or has been fused to other pieces of glass will be either common laboratory borosilicate glass or fused silica. Any soft glass made into laboratory apparatus is for special application or, more likely is very old (and ought to be in a museum). 

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