Powder paste, wetted

Powder cake, wetted or Powder paste, wetted with not less than 17 per cent alcohol by mass 0433... 

Powder Cake (Powder Paste), Wetted Substance consisting of nitrocellulose impregnated with not more than 60% of nitroglycerin or other liquid organic nitrates or a mixture of these. UN App. B, ICAO A2... 

It may well be a Japanese custom to sit on the floor to assemble shells, but it is rational, for it is possible to arrange all the components and tools around the worker and to avoid the shock caused when things fall on the floor. (But as described later, for shells which require less explosive than Warimono a working bench is often used in ordinary manufacture.) The operator must take care not to build up a mass of material around the working area. When chlorate compositions are used, have a wet cloth to hand, and wipe the hands with it immediately after handling each composition. Cutting powder pasted paper or quick match must be done in another room. 

Ceramic fonning typically involves using pressure to compact and mould particles to the desired size and shape. Ceramics can be fonned from slurries, pastes, plastic bodies (i.e. such as a stiff mud), and from wet and dry powders. 

The paste-extmsion process includes the incorporation of ca 16—25 wt % of the lubricant (usually a petroleum fraction) the mixture is roUed to obtain uniform lubricant distribution. This wetted powder is shaped into a preform at low pressure (2.0—7.8 MPa or 19—77 atm) which is pushed through a die mounted in the extmder at ambient temperature. The shear stress exerted on the powder during extmsion confers longitudinal strength to the polymer by fibrillation. The lubricant is evaporated and the extmdate is sintered at ca 380°C. 

The conventional sulfur dye powder is made into a paste with a small amount of soft water and an alkah-stable wetting agent. Boiling for a few minutes in a strong solution of sodium sulfide reduces the dye. The dissolved dye is diluted to the requited dyebath volume. When dyeing pale shades, the final bath should contain at least 5 g/L sodium sulfide (60%), inrespective of the amount used to dissolve the dye. 

To reduce labor and other expenses, most sintered nickel plaques are produced by a wet-slurry method. A nickel slurry is prepared by mixing a low density nickel powder with a viscous aqueous solution such as carboxymethylceUulose [9004-42-6] (CMC). Pure nickel gau2e, a nickel-plated gau2e, or a nickel-plated perforated steel strip is continuously carried through a container filled with the nickel paste and sintering is done in a hori2ontal furnace. The time of the sinter in the furnace is ca 10—20 min. 

Bulk Blenders Vlanv of the mixers used for solids blending (Sec, 19) are also suitable for some liquid-solids blending. Ribbon blenders can be used for such tasks as wetting out or coating a powder, When the final paste product is not too fluid, other solids-handling equipment finds frequent use. 

Solids handling frequently has the potential for dusting, which can lead to potential health and explosion hazards. Handling solids in the form of larger particle size granules or pellets rather than a fine powder reduces the potential for worker exposure. Worker exposure hazards are reduced by formulating dyes as liquids or wet pastes rather than dry solids or powders (Burch, 1986). 

A typical plot of torque versus amount of liquid (di-butyl-phthalate, DBT) added is given in Fig. 15 for a very porous sodium carbonate powder mixture. The increase in measured torque at around 25% by volume DBT and again at around 65 %, can easily be seen (the final decrease in torque upon the formation of the wet cake is not shown). These two points correspond to the condition under which the continuous network of bridges forms, at about 25% liquid present, and the formation of the dry paste, at around 65%, where enough binder is available to fill most internal voids. The amount of liquid in Fig. 15 is given as a fraction of the total volume of powder, instead... 

Put 10 g of powdered sugar into a 50-ml beaker, wet it with water until a thick paste forms, and then add 3-5 ml of concentrated sulphuric acid. Rapidly stir the contents with a glass rod and see what happens. What gaseous substances are obtained ... 

Natural alizarin of madder is now scarcely ever used, commercial alizarin being obtained artificially. It forms either a wet, ochre-yellow paste, usually containing about 20% of solid matter (sometimes as much as 40 or 60%) or dry powder or lumps... 

---