Tubing thread preparation

Irradiation Procedure. Reaction mixtures were prepared at room temperature by transferring desired quantities of reactants from their storage bulbs to the reaction vessel, a 500-cc. spherical borosilicate glass flask attached to the vacuum line by a section of glass capillary tubing and a 4-mm. bore threaded glass valve with a Teflon plug (Fischer and Porter 795-609). Prior to each experiment this vessel was baked under vacuum at 500°C. for 12 or more hours. 

Additional reports on olefination reactions have appeared [64] including the preparation of several phosphonium salts using a domestic MW oven wherein the reaction of neat triphenylphosphine and organic halide shows remarkable rate enhancement in a pressure tube with a threaded Teflon cap [65]. 

Figure 6.13. Experimental arrangement of the hot-explosive compaction method for the preparation of consolidated Ni-Al alloys (after Kecskes etal. 2004). (a) Precursor powder sample inside a steel-tube container placed in, (b) an asbestos thermal insulation sheet (c) a concentric card-box filled with the powdered explosive (80% NH4NO3 + 20% TNT) (d) threaded steel plugs serving as contacts for the preliminary heating and to be lifted off just before detonating the explosive (e) detonating cords.

Prepare a fused glass tube 2-3 cm long and about 1 cm in diameter. Carefully introduce the end of the tube into the upper part of the bag and fasten the bag to the tube with thread. Store the bag in a beaker in water. 

The authors prepared a molecular tube by crossUnking adjacent a-CD units in a polyrotaxane (molecular necklace) [126,127] (Scheme 4). The molecular necklace was dissolved in 10% NaOH, to which epichlorohydrin was then added. Epichlorohydrin was allowed to react with the hydroxyl groups of the threaded a-CD to link up each a-CD. 2,4-Dinitrofluorobenzene moieties, bulky stoppers, at both ends were removed by the treatment with a strong base (25% NaOH). The yield of molecular tube was 92% and the average molecular weight was estimated to be ca. 2 x 10" by GPC. The molecular tube could accommodate Is" ions in an aqueous solution of KI-I2 efficiently, whereas a-CD could not. 

Fig. 3.6. UV-vis spectra recorded from the as-prepared gold colloidal solution (curve l),the gold colloidal solution after capping with a-CD threaded ODT molecules (curve 2), the chloroform solution after phase transfer of the gold nanoparticles (curve 3), and the aqueous gold colloidal solution after phase transfer of the gold nanoparticles into chloroform (curve 4). The inset is a picture of test tubes containing...

Fig. 356. Preparation of calcium amalgam, b steel bomb, 19 cm. long, 5.5 cm. I.D., 9 mm. wall thickness capacity 45 ml. up to the screw thread s movable piston k steel head r pressime-reducing valve m pressure gage d copper pressure tubing for introduction of Ng.

MAJOR APPLICATION H-H PVC is mostly studied in academic field to understand its structure/property relationship, thermal degradation behavior, and mechanism. Its properties are compared to those of commercial head-to-tail PVC. Pure H-H PVC has no significant industrial applications. H-H PVCs containing 40-65 wt% of Cl, also called chlorinated polybutadiene rubber-resins, are used for coating, paint-based applications and the preparation of threads, tires, tubings, and films, etc. 

The first weather-protected application concerned house service installations comprising one phase and one neutral core. The termination for this consists of a Y-shaped heat-shrinkable moulding. The house service cable is prepared by stripping off the lead sheath and separating the phase and neutral cores with the insulation intact. These are then threaded up and out of the arms of the Y piece. The Y piece is then shrunk so that it overlaps the lead sheath and the upper arms are covered with tubing. An ordinary propane gas torch is used as a heat source and the total shrinking time is less than 5 min. A suitable earth clip is fitted to the lead sheath to provide consumer earthing facilities. 

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