Oven predrying

All glassware is predried in an oven at 120°C for 1 hr, assembled while hot, and allowed to cool under a stream of nitrogen. 

Extraction container, predried Glass holding tube Forced-air oven Dessicator... 

The experimental details have been described already in detail (19,20,21), The paper substrate can be selected, or pretreated, in a way designed to optimize the phosphorescent intensity. Sample delivery consists of spotting 3 fiL of sample solution on a circle of filter paper 0.6 cm in diameter. Predrying with an IR heating lamp proved to be more eflBcient than the use of desiccators, blowers, or ovens 19 20 21 22), Maintenance of the dried state of the material during spectroscopic measurement is achieved by blowing warm, dried air through the sample compartment. The previously mentioned Perkin Elmer spectrofluori-... 

This method, proposed by Hackpill, uses the apparatus shown in Fig. 262. A weighed amount of RbCl (CsCl) is thoroughly predried in an oven at about 150°C and mixed with the required amount of Ca turnings. An iron insert crucible b is filled with the mixture and stoppered with a plug c made of fine steel wool. A ratio of 10 g. of RbCl (15 g. of CsCl) to 8 g. of Ca has proven satisfactory. The apparatus (Fig. 262) with a reaction vessel 30-35mm. in diameter, will hold a maximum of about 35 g. of RbCl (50 g. of CsCl), together with the appropriate amount of Ca. 

List the history of the sample before it was sampled (this might be just from the bottle , but might include grinding, sieving, predrying in an oven, surface modification, etc.). 

Thermal dryers are sometimes used for predrying, but are almost always used for final drying because of the limitations of mechanical dryers. After mechanical predrying, much of the remaining water is chemically bonded to the fiber and must be evaporated. This is accomplished using several types of thermal system such as heated cans, convection ovens, and radio frequency (RF) dryers. Recently, microwave dryers have been designed for drying textiles and carpet tiles [5]. 

Steam cans are used in predrying and final drying of fabrics. They are often used to predry fabrics that must be dimensionally stable after final drying. The steam cans are nsed to reduce the moisture regain to about 30%, and convection ovens with tenter frames are used for final drying. In some cases where contact with the hot surface does not... 

IR ovens are typically used to predry materials that are finally dried in tenter-frame convection ovens. They are also used to augment the existing ovens where additional production is needed and space is limited. IR ovens are not normally used to accomplish final drying because IR energy is absorbed by dry textiles and there is a danger of scorching or burning the product. 

Special precautions. The reaction is carried out under argon in predried glassware the reaction vessel should be wrapped in silver foil. Molecular sieves must be predried in the oven and activated for 10 min under vacuum at 300 °C. 

Molecular sieves 3 or 4 A (predried in oven) Aqueous NaHCOa... 

Polycarbonate parts having thickness of at least 40 mils can be successfully hot gas welded. Bond strengths in excess of 70 percent of the parent resin have been achieved. Equipment should be used capable of providing gas temperature of 315 to 648°C. As prescribed for the heated tool process, it is important to adequately predry (120°C) both the polycarbonate parts and welding rods. The bonding process should occur within minutes of removing the parts from the predrying oven. 

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