Teflon tapes

All of the pieces pictured here are not going to fit perfectiy into each other and that s going to cause all sorts of leaks. The answer is teflon tape. Strike loves teflon tape This inexpensive product is found in the plumbing department of any hardware store and is the duct tape of the next century. Teflon tape is chemically and thermally indestructible. This stuff is wrapped around any piece of pipe or joint, said part then jammed into its appropriate receptacle and the tape will mold to form a perfect fit. Hell, it can mummify a whoie joint compiex to make it absolutely impregnable. 

Shipment and Storage. Sulfur dichloride, if kept dry, is noncorrosive at ambient temperatures, thus carbon steel and Hon can be used Hi the constmction of tanks, piping, and dmms. However, when water or humidity is present, materials resistant to hydrochloric acid must be used, eg, glass-lined pipe. Teflon, titanium, HasteUoy C, or possibly a chemically resistant, glass-reiaforced polyester. Threaded pipe joHits should be assembled with Teflon tape. Hoses should be constmcted with a Teflon inner lining with the outer tube constmcted of Neoprene or braided 316 stainless steel protected by an adequate thickness of Teflon. Sulfur dichloride should be stored away from heat and away from dHect rays of the sum. Toluene and sulfur dichloride react exothermically when catalyzed by Hon or ferric chloride. Safety precautions should be foUowed when such a mixture is present (165). 

Round-bottom flasks, 125- and 500-mL Teflon culture tubes, 15-mL Teflon tape... 

Concentrate the acetonitrile extracts obtained above to dryness below 40 °C with the rotary evaporator. Dissolve the residues in 2 mL of acetone. Quantitatively transfer the acetone extracts to a culture tube with a Teflon screw-cap containing 250 xL of acetone-olive oil keeper (1 1, v/v). Evaporate the acetone on a heating block not exceeding 40 °C under a stream of air. Wrap the threads on the Teflon culture mbe with Teflon tape and add 2.0 mL of 50% (w/w) sodium hydroxide. Cap tightly and heat the Teflon culture tube at approximately 200 °C for 3 h. 

Quartz fine aggregate and normal Portland cement were used to prepare mortar with a w/c of 0.5. A cylindrical specimen, 43 mm in diameter and 50 mm long, was cast and cured under sealed conditions for 3 days at 23 °C. The specimen was then oven dried at 105 °C for 1 day prior to exposure to lithium nitrate solution. The specimen was then placed such that the bottom of the cylinder was submerged approximately 1-2 mm into a lithium nitrate solution with Teflon tape applied to the curved surface. 

Initially, the as-received pump could not pass a 13.8-bar (200 psig) static pressure test at ambient temperature. Consequently, the pump was returned to the manufacturer for extensive seal modifications. Upon receiving the modified pump, the unit was placed into service for a hot shakedown test with C30 oil at 175 psig pressure under the present experimental setup. The modified seal continued to leak at a small but acceptable rate on the order of 1 g/min. However, leak problems were encountered in the threaded seal of the stator and the pump housing. The stator was resealed with a thick Teflon tape and a high-temperature pipe sealant that initially slowed the total system leaks to less than 50 g/h. 

Ru(III) chloride (18.2 g, Johnson-Matthey, Mallory Ltd.), Ti(IV) butoxide (45 ml, Aldrich) and 37% HC1 (6 ml) were mixed together to make the coating solution. The Ti electrodes were dipped into this solution and allowed to air-dry and then heated at about 5°C min-1 to 100°C, remaining at this temperature for 15 min to remove the solvent. The temperature was then increased at 10°C min-1 to 440°C in air and maintained at 440°C for 30 min to decompose the Ru/Ti compounds, thus forming the mixed Ru/Ti oxides. Subsequently, the length of the oxide-coated Ti wire was wrapped in Teflon tape, leaving only the cross-sectional end as the WE for immersion in solution. 

All glass apparatus is dried in an oven at 100°C and assembled while still hot under dry nitrogen flow. All ground glass joints are tightly sealed with a Teflon tape and then wrapped with parafilm. 

We sought to expand the range of catalysts and fluorous supports that could be applied in Fig. 1, and developed a surprisingly effective procedure involving common commercial Teflon tape. As described below, this provides not only a convenient means of catalyst recovery, but also of catalyst delivery. From an engineering standpoint, tapes offer a variety of unique attributes, and it is reasonable to extrapolate that meshes and/or reactor parts such as liners could be fabricated with similar properties. 

Fig. 8 Recycling of the thermomorphic fluorous rhodium catalyst 16-Rf using Teflon tape...

One obvious procedural refinement would be to precoat the catalyst on the Teflon tape. This would allow low loadings to be delivered by length as opposed to mass measurements, or the tedious preparation of standard solutions. Accordingly, strips of tape were added to a solution of 16-Rf6 in CFaCeFii. The solvent was removed under an inert gas stream to give a yel-... 

As would be expected, fluorous compounds are preferentially retained on fluorous silica gel [62]. Similarly, fluorous catalysts can be adsorbed on fluorous silica gel. These materials have been applied to reactions in organic solvents and water, both at room temperature and above [63-69]. The investigators have usually interpreted the transformations as bonded fluorous phase catalysis , which corresponds to sequence B-II in Fig. 1. However, there remains the possibility that at least some catalysis proceeds under homogeneous conditions via desorbed species. To our knowledge, fish-out experiments analogous to that conducted with the Teflon tape in Fig. 8 have not been conducted. 

Some potential limitations associated with this protocol merit note. For example, with sequence A in Fig. 1, insoluble by-products will interfere with catalyst recovery. With sequence B, interference will depend upon the type of support. For instance, the Teflon tape in Fig. 8 should be easily separable from another solid material, as would a mesh or reactor liner. Also, since heating is required to achieve homogeneity, the method is best suited for reactions conducted at elevated temperatures. However, there are many reactions which proceed rapidly under fluorous/organic liquid/liquid biphase conditions (i.e., before the miscibility temperature is reached) [55-57,70]. Therefore, it is not unreasonable to expect that sohd fluorous catalysts with little or no solubility can also efficiently promote certain reactions, as represented by sequence A-1 in Fig. 1 [29]. 

A. Butane or Propane Valve Assembly. Use only the best equipment. Teflon tape all threads before assembly. 

A steel plate ca 3/8 inch thick is used to cover the cup. The cup for noncorrosive liquids is made from galvanized 1-inch welded steel pipe 3 inches in length with a brass disk 0.0015-inch thick attached at the bottom. For corrosive liquids, the pipe is coated inside with Teflon and the bottom is Teflon tape 0.003-inch thick. It has been found that a Teflon bottom attenuates the booster shock somewhat less than does brass. The sensitivity value for a given liquid explosive is taken as the number of 10 mil cellulose acetate spacer cards required for a gap at which the liquid explosive detonates in 50% of the test shots... 

Figure 2. Canula filter. The Teflon tubing is inserted through the NMR tube septum. The filter paper is taped onto the pyrex tubing using Teflon tape.

In particular, if a latex is to be used for coatings, adhesives, or film applications, no silicone-base stopcock greases should be used on emulsion polymerization equipment. Although hydrocarbon greases are not completely satisfactory either, there are very few alternatives. Teflon tapes, sleeves, and stoppers may be useful, although expensive. 

Tests were performed to determine the stability of sorbed analytes in tubes that had been exposed to generator effluent and that were then stored for at least 7 d. For each method, the analyte concentration in the generator effluent was maintained at about 0.3 X LAQL per liter 3 L of the generator atmosphere was sampled at a rate of 0.2 L/min to yield a tube loading of about the LAQL. Following exposure, the sorbent tubes were sealed with Teflon tape and plastic caps for storage. 

Figure 1. Sensor cell assembly 1, reservoir housing 2, cap 3, support plate 4, M E assembly 5, base plate 6, gasket 1, contact pin 8, thermistor 9, nylon screw 10, Teflon tape 11, gasket 12, gasket 13, counter electrode 14, sensor electrode 15, reference electrode 16, thermistor.

PIPE THREAD WITH SEVERAL LAYERS OF TEFLON TAPE... 

Figure 9.9 Assembly of sandwich-type optically transparent thin-layer electrochemical cell, a, Glass or quartz plates b, adhesive Teflon tape spacers c, minigrid working electrode d, metal thin-film working electrode, which may be used in place of (c) e, platinum wire auxiliary electrode f, silver-silver chloride reference electrode g, sample solution h, sample cup. [Adapted with permission from T.P. DeAngelis and W.R. Heineman, J. Chem. Educ. 53 594 (1976), Copyright 1976 American Chemical Society.]...

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