Suction pad

In 1974, Vogtle and Weber disclosed the preparation of a class of molecules which they reported showed remarkable phenomenological parallelisms to the mode of food capture by an octopus using its suction pads . Such molecules have also been referred to as hexa-hosts (see below). 

Continuous immersion of the fabric in a dyebath and removal of the excess of liquor by squeezing or suction (padding). 

Fig. 2.rj. (a) Rubber suction pad sealing against a smooth surface, (b) Pullirtg the suction pad creates a vacuum which causes adhesion. 

It is obvious that this suction effect is not true molecular adhesion. Suction pads work better as you dive beneath the ocean where the gravitational pressure increases. But they get worse as you climb a mountain, eventually becoming useless in space. Molecular adhesion should remain the same, at the bottom of the sea or out in space, independent of gravitational effects. 

The two most easily distinguishable forces of attraction are suction and liquid bridge adhesion. The suction pad, as explained in Fig. 2.5, relies on atmospheric pressure to hold the bodies together. This pressure remains constant as the pad is pulled away from its substrate. The same is true of a liquid droplet acting to glue two balls together the force of adhesion is constant as the balls separate, as shown schematically in Fig. 2.12. Thus these two types of adhesion... 

Oval. Reddish coat of anterior part of body covered with extremely fine hairs. Ventral suction pad and separate genital suction pad. 

Norite, is heated to boiling by introduction of steam, filtered through a Norite filter pad by suction, and cooled in an ice-salt bath. The muconic acid is precipitated by the addition of a large excess (1500 ml.) (sp. gr. 1.18) of concentrated hydrochloric acid to the cold solution. The acid is added in a thin stream to the well-stirred solution. After 2 hours the muconic acid is filtered, washed first with two 400-ml. portions of cold water and then with 200 ml. of methyl alcohol, and dried at 85°. The yield of nearly colorless product melting at 296-298°, with decomposition, amounts to 165-195 g. (37-43%). 

Quinoline hydrochloride solution. Add 20 mL of redistilled quinoline to 800 mL of hot water containing 25 mL of pure concentrated hydrochloric acid, and stir well. Cool to room temperature, add a little filter paper pulp ( accelerator ), and again stir well. Filter with suction through a paper-pulp pad, but do not wash. Dilute to 1 L with water. 

A solution of LD A (0.1 mol) inTHF (75 ml), prepared as above, was then cooled to — 78 °C, and a solution of the TMS carboxylate (0.1 mol) in THF (40 ml) was added with stirring, which was continued at —78 °C for a further 30min. Excess TMSC1 (0.5 mol) was added over 5 min, and the reaction mixture was allowed to come to ambient temperature over 30 min with stirring. It was then filtered by suction through a pad of Celite, and concentrated using a rotary evaporator. The residue was taken up in ether (50 ml), and filtration and concentration were repeated. Distillation of the residue gave the ketene bis(trimethylsilyl)acetals, ca. 90%. 

Subsequent collapsing of the foam is generally by collapse onto the fabric (controlled to some extent by the chemicals used), by vacuum suction of the foam into the fabric, or by means of a pad nip. 

Pumps shall be designed so that they may either float with the suction and discharge pipe, or be bolted to a pad or foundation. 

The dislodged sections of the demister pad are blown into downstream equipment, as into the suction of a centrifugal wet-gas compressor. 

After the main filtrate has been removed for such treatment, the crystals on the filter pad should be washed to remove remaining traces of mother-liquor which, on drying, would contaminate the crystals. The wash liquid will normally be the same solvent or solvent mixture used for recrystallisation and must be used in the smallest amount compatible with efficient washing, in order to prevent appreciable loss of the solid. With the suction discontinued the crystals are treated with a small volume of the chilled solvent and cautiously stirred with a spatula or with a flattened glass rod (without loosening the filter paper) so that the solvent wets all the crystals. The suction is then applied again, and the crys-... 

Regarding the need for absolute removal of all free liquid mist, such as with a gas turbine compressor suction scrubber, I find a 100-pm particle size selection to be good design practice. This particle size fallout before reaching a demister pad will indeed ensure that most any demister pad will remove all remaining free liquid mist. 

Gas-phase liquid particle. The gas-phase liquid particle size of choice is generally 150 pm or less, which results in excellent gas-phase separation of liquids. For more critical liquid particle removal, such as with turbine blade gas suction, a 100-pm particle size input is recommended with a supporting demister pad in the separator. 

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