Dip bar

A stainless-steel dip tank is on the bottom of the coating tower. Inside the tank is a submerged roll, sometimes called dip bar, which may be made from stainless steel or PTFE.8 The roll may be locked or rotated. A rotating bar most frequently has sleeve bearings, which are lubricated by the liquid in the tank. Some designs use multiple rolls (typically three, see Figure 6.2) this arrangement reduces differences in pickup between the two sides of the web. 

Unlike in the coater with steel belts, in this process equipment applicators such as wire-wound bars are nsed, which may be designed to rotate to assure a better, more uniform coating. The dip tanks are similar to those used in fabric coating, also nsing an immersed dip bar. To prevent coating defects due to shear, the dip tanks have double walls and are chilled by circulated chilled water to temperatures below 19°C (66°F), the hrst-order transition temperature. 

Teflon support with its glass side facing the gas inlet the autoclave was evacuated (10 min, < 1 mbar), carefully filled with HCl gas (1 bar) and heated to 110°C for 15 min. After opening the autoclave the HCl vapors were blown out with a stream of cold air (5 min) and the HPTLC plate was cooled to room temperature. In order to intensify and stabilize the fluorescence the plate was dipped in a solution of liquid paraffin in chloroform (30 + 70) for 15 s. 

In fact, the vent on the tank was choked. The gauge air pressure (75 psi or 5 bar) was sufficient to burst the tank (design gauge pressure 5 psi or 0.3 bar). Originally the tank had a 6-in.-diameter vent. But at some time this was blanked off, and a 3-in.-diameter dip branch was used instead as the vent. 

If a bar of zinc is dipped into a solution of zinc sulphate, the former acquires a negative, the latter a positive charge, and a difference of potential is established at the boundary the magnitude of which depends on the concentration of the solution. There is in fact an electrical double layer produced, which is formed of negative charges on the metal (which has lost ions into the solution) ... 

FIG. 21 Cross section of sample subjected to 10-fold alternating dipping into dispersions of lb (5X) and 2 (5X). The bar indicates the average particle film thickness of 1.2 p,m. (From Ref. 93, with permission from Elsevier, Amsterdam.)... 

A 4.9 g sample of the liquid siloxane in a glass dish was put into a bomb calorimeter (on an open bench) containing 5 ml of sodium hydroxide solution to absorb combustion gases. The electric igniter system consisted of a metal wire in contact with a cotton-wool wick which dipped into the siloxane sample. The bomb was sealed, pressured up to 39-44 bar with oxygen, and the igniter was fired. A violent explosion blew the lid off the bomb (rated at 190 bar working, 250 bar test), and examination of the deformed bomb indicated that a maximum detonation pressure of around 900 bar had been attained. 

Then, in 1998, Harvard researchers dipped into chocolate and published a study that made headlines around the world. They tracked the health status of nearly eight thousand male Harvard graduates, all over the age of sixty-five, and concluded that those who ate one to three chocolate bars a month lived, on average, a year longer. More chocolate-eating, unfortu-... 

The universally accepted primary reference half-cell is the standard hydrogen electrode. The electrode consists of a noble metal (platinized platinum) dipping into a solution of hydrogen ions at unit activity and saturated with hydrogen gas at 1 bar (i.e. 1 X 105 Pa, which in practical terms may be taken to be equal to 1 atmosphere). In practice such a standard electrode cannot be realized, but the scale it defines can. 

Equip a 100-ml round-bottomed two-necked flask with a magnetic follower bar, a dropping funnel and a thermometer positioned to dip into the reaction mixture. Site the flask in a plastic bowl on a magnetic stirrer unit. Place in the flask a solution of lg (0.0055 mol) of trans-l-ethynyl-3,3,5-trimethylcyclo-hexan-l-ol (Expt 5.41) in 10ml of acetone and add a solution of 1.25 g... 

Chill until cold and slice the bars using a knife dipped in hot water. Place the cut bars on a stacked serving tray or on a plate. 

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