Tubing connectors

Correct and incorrect methods of installing ilared-tube connectors are illustrated in Figure 40.38. Tubing nuts should be tightened with a torque wrench to the values specified in applicable technical publications. 

Total micro-channel surface area 6.24 10- m Tube connectors inner diameter length 6 mm 40 mm... 

Tube connectors inner diameter 1/8 in Total number of microstmctured platelets 6... 

Two sets of stoppers are very useful, one set unbored and a second set with a single hole bored in them to carry blowing-tube connectors. A longer piece of glass tubing inserted into the hole will also form a very adequate handle when working small pieces of apparatus. 

In a 2-1. four-necked flask (or a three-necked flask with a Y-tube connector) equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer extending nearly, to the bottom of the flask is placed 550 ml. (595 g., 5.83 moles) of acetic anhydride which is cooled to 0° with an ice-salt bath. Then 180 ml. (300 g., 2.09 moles) of a 70% solution of perchloric acid is added with stirring at a rate such that the temperature does not rise above 8° (Note 1). This step takes about 3 hours. The mixture is continually cooled and stirred, and 240 ml. (204 g., 2.09 moles) of mesityl oxide is then added slowly. The slow addition of 370 ml. (400 g., 3.92 moles) of acetic anhydride follows. The ice bath is then replaced by a water bath the temperature of the reaction mixture will usually rise to 50-70° because of the heat liberated by the exothermic reaction, and the reaction mixture will turn dark. The reaction mixture is heated on a steam bath for 15 minutes to complete the reaction, and the mixture is then allowed to cool and stand at room temperature for 2 hours. The crystals,... 

It is important that the tubing connector remain open to the air or else the entire apparatus will, quite simply, explode. 

Cells for blood tests, syringes, centrifugation tubes, needle hubs, transparent tubes and tubing connectors, nebulizer parts, urine samplers. .. 

In a 1-1. four-necked flask (or a three-necked flask with a Y-tube connector) equipped with a mechanical stirrer, a reflux condenser, a dropping funnel, and a thermometer are placed 208 g. (1.00 mole) of benzalacetophenone (Note 1), 60 g. (58.5 ml., 0.50 mole) of acetophenone, and 350 ml. of 1,2-dichloroethane. The contents of the flask are warmed to 70-75°, and 160 ml. of a 52% ethereal solution of fluoboric acid (Note 2) is added from the funnel with stirring during 30 minutes. With the first addition the mixture becomes orange subsequently the color changes to brownish yellow. After the addition is completed, the mixture is stirred and heated under reflux for 1 hour (Note 3). The fluorescent mixture is allowed to stand overnight in a refrigerator. The crystalline product that separates is collected on a Buchner funnel and washed well with ether. By addition of 250 ml. of ether (Note 4) to the mother liquor an additional quantity of 2,4,6-triphcnylpyrylium tctrafluoroboratc is obtained. A total yield of 125 135 g. (63 68%) of yellow crystals... 

Polyacetal resins have a repeating unit of -O-CH2-. They are strong, stiff polymers for valves, hoses, and tube connectors. Pentaerythritol finds end-uses in alkyd resins and explosives (pentaerythritol tetranitrate). To appreciate this synthesis, the student should review two condensation reactions, the crossed aldol and the crossed Cannizzaro. Acetaldehyde reacts with 3 mol of formaldehyde in three successive aldol condensations. This product then undergoes a Cannizzaro reaction with formaldehyde. 

Amounts of consumables (resins, membranes, filters, disposable bags, and tubings/connectors) that end up as solid wastes could be large. 

Connect a piece of pump tubing to the outlet tubing connector of a side-outlet gradient maker. 

E. Miscellaneous Tubing Connectors. The variety of tubing couplers is enormous and a comprehensive list would be out of place in this book, but several additional types will be mentioned here which are useful in the laboratory. Metal standard taper and metal ball joints are available, and these will mate with corresponding ground-glass joints to provide one means of connecting parts made of dissimilar materials.4 As with glass standard taper joints, the seal is... 

Fig. 10.7. Flange tubing connectors, (a) Cajon VCO O-ring sealed Fitting (b) Cajon VCR metal gasketed flange fitting. (Reproduced by permission of the copyright holder, Markad Services Co.)...

Channel length 322 mm Outlet connector 1 /8 inch steel tube connector... 

Mixer/funnel linear, tube connector bendt, tube linear Mixer type 8, 0.30 m long bend connector with 0.3 mm i.d., 0.75 m long tube with 0.3 mm i.d. 0.400 mol I"1, 2000 1 h 1 30 s, system plugged owing to extensive Et3NHCl lump formation... 

Pressurize the reagent container with an inert gas line using a syringe needle attached via a tubing connector. 

The efficiency of any chromatographic system wfll be reduced if noncolumn contributions to band spreading are not properly minimized. For example, precolumn and postcolumn tubing, connectors, column fittings, and detector cell must all be of minimum volume. 

This bubbler is constructed from a 12" length of 3" inner ID (inner diameter) schedule 40 PVC pipe. Two 3 PVC caps are the bottom and top. Tube connectors are PVDF single barbed tube fitting, with a 90° elbow x NPT male for 3/8" tube ID, V2" NPT. Plastic 1" tubing, 9V2" long, extends down into the bubbler tube from the tube connector in the top cap. Fiberglass screen mounted on the lower end of the tubing breaks up the gas stream into smaller size bubbles. Assembly... 

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