Capillary bleed tube

Fig. A3.17. Capillary bleed tube for reduced pressure distillation.

Follow-up Tests. In our follow-up tests we want to better define at what temperature we can detect the thermal instability, and to gain some knowledge about how much of a hazard the instability represents. The majority of this work is done with an instrument called a Sikarex Safety Calorimeter (3,4) xt consists of a sample oven, a control and measurement module, and a recorder. In the sample oven is placed 10-30 g of sample in either an open glass tube, a closed glass tube with a capillary bleed, or a stainless steel autoclave. The control and measurement module controls the oven temperature and measures the sample and oven jacket temperatures. 

In the normal rest position, carrier gas is fed to the top of the column at pressure PI through a gauge G1 and a buffer volume B1. Excess of carrier-gas bleeds back through the injection capillary, cleaning out the tube, and is allowed to vent to atmosphere via the side arm (d), which is connected through the buffer B2 and the valves V2 and V3. 

Active sampling using dual multisorbent (Carbopack C, Carbopack B and Carbosieve Sill) tubes over a period of eight hours was employed. The sampled VOCs were desorbed using an automated TD system and transferred via a heated fused silica line into a GC. The VOCs were separated on a low bleed capillary column, identified and quantified by their retention times and target and three qualifier ions using mass spectrometric procedures. The details of the analytical procedures can be found elsewhere (Zuraimi et al., 2006). 

Solvent Removal After extraction, chromatography, or completion of a reaction, it is frequently necessary to remove a solvent prior to further treatment of the product. An efficient method for accomplishing this is to use a solvent stripper as shown in Fig. 2-23. The sample to be concentrated is placed in a flask that is filled no more than half full, and a fine capillary tube (air or nitrogen bleed) is inserted through the distillation head to the bottom of the distilling flask. The solvent is heated with either a hot water or steam bath while aspirator vacuum is applied. If the rate of distillation... 

In a hood, behind a safety shield, in a 250-ml flask fitted with a thermometer, a fine capillary tube connected to a drying tube for an air bleed, and a distillation column packed partially with copper cloth (see above) topped with a spray trap and a total reflux, partial take-off distillation head are placed 100 ml of glacial acrylic or methacrylic acid and 1 gm of A,N -diphenyl-/ -phenylenediamine or phenothiazine. 

HaargefaC capillary air bleed/ boiling capillary/ air leak tube dist Siedekapillare capillary blotting Diffusionsblotting capillary breaking/ capillary fracture (fibers) Kapillarbruch... 

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