Water-based sprays

Figure 6 shows the resulting downwind drift-loss pattern when an oil and a water-base spray of the same drop size is used. Here the evaporation of the water reduces the deposit at points closer to the application while the non-evaporative oil shows a higher deposit out to about one mile, where the two curves cross. The characteristic of non-evaporative oil sprays is to deposit in greater amounts out to about one mile distance when compared with water base sprays, also the oil appears to have less material left to deposit beyond the one mile. Thus a low evaporative base spray produces a wider extended swath and requires wider buffers than a water-base application. 

The increase in successful treatments with synergized pyrethrins in the USA led lo applications by Bulk Handlers in Australia, and trials in South Africa (Jouhert, 1965 Joubert and DeBoer, 1968 Joubert and du Toil, 1968). The South African work concluded that a water-based spray at a dosage of 1.25 ppm of pyrethrins 12,5 ppm PBO afforded excellent protection to maize against insect infestation for a year. 

Quick response over a wide area is also required in migrant pest control, and high volume application rates with water-based sprays are not feasible for inhospitable terrain. 

The neutralisation of this resin and the blending of a crosslinking agent would be as follows. This material is suitable as an anti-corrosive water based spray applied coating, the formulation of which is given in the Waterborne Chapter (Chapter 7). 

Uses Defoamer, antifoam for aq. pesticide sprays defoamer for food processing Features Designed to prevent or alleviate foaming problems associated with some pesticide formulations in water-based sprays Regulatory FDA21CFR 173.340 RCRA, CERLCA nonreportable not regulated for transport SARA Immediate Health Hazard Properties Wh. milky liq. faint odor disp. in water sp.gr. 0.97-0.98 (75 F) dens. 8.10-8.20 Ib/gal vise. 600 max. cps f p. < 35 F flash pt. > 200 F 20% act. < 1% volatiles... 

VOC-free, water-based spray and foam fluxes for wave soldering and VOC-free solder pastes for reflow soldering have been developed. The high latent heat of vaporization of water puts high demands on the preheating section of wave soldering machines. 

Uses. Tetrahydrofurfuryl alcohol is of interest in chemical and related industries where low toxicity and minimal environmental impact are important (134). For many years tetrahydrofurfuryl alcohol has been used as a specialty organic solvent. The fastest growing appHcations are in formulations for cleaners (135) and paint strippers (136), often as a replacement for chlorinated solvents (137). Other major appHcations include formulations for crop sprays, water-based paints, and the dyeing and finishing of textiles and leathers. Tetrahydrofurfuryl alcohol also finds appHcation as an intermediate in pharmaceutical appHcations. 

An emulsion system in which the propellant is in the external or continuous phase is shown in Figure 2b. As the Hquefied propellant vaporizes, it escapes direcdy into the atmosphere, leaving behind droplets of the formulation which are emitted as a wet spray. This system is typical of many water-based aerosols or w/o emulsions. 

In the Spray Test (AATCC Test Method 22), water is sprayed on a taut surface and rating is based on comparison with a standard chart (14). 

The KEN-FLOTE column (11) is one of several column flotation processes based on a countercurrent principle. The feed slurry containing reagents is iatroduced iato the column just below the froth zone. Air is iujected at the bottom of the column via an air sparger. Wash water is sprayed within the froth zone to reject the entrained impurities from the froth. Test results on this column iadicate that a 6% ash product coal having a combustible-recovery of 75—80% can be obtained. A 70—80% pyrite reduction is also claimed. Figure 2 shows the operation of such a column. 

Because most latices have low viscosities by compounding, most of the waterborne rubber adhesives are sprayable. Thickeners such as fumed silicas can be added to increase viscosity and thixotropy. This means that even at relatively large viscosities (over 10 Pas) many water-based rubber adhesives can be sprayed. Dip and curtain applications require viscosities between 0.05 and 0.3 Pas, whereas brush application works with viscosities between 1 and 50 Pa s. 

For the remedial treatment of fungal decay and insect attack on timber in buildings, clear solvent-type preservatives applied by spraying all available surfaces are generally used, supplemented with wood preservative pastes to obtain deep penetration. Water-based emulsions are also used for woodworm control. There has been a general move towards the use of those... 

Water-base coatings for spray and roller coat application... 

The extrusion process requires the use of a lubricant to prevent adhesion of the aluminum to the die and ingot container walls. In hot extrusion, limited amounts of lubricant are applied to the ram and die face or to the billet ends. For cold extrusion, the container walls, billet surfaces, and die orifice must be lubricated with a thin film of viscous or solid lubricant. The lubricant most commonly used in extrusion is graphite in an oil or water base. A less common technique, spraying liquid nitrogen on the billet prior to extrusion, is also used. The nitrogen vaporizes during the extrusion process and acts as a lubricant. 

Water spray systems for hydrocarbon facilities are routinely specified because of the rapid application means the system can provide and the excellent heat absorption a water based system represents. Water sprays are also used when passive fire protection measures (i.e., fireproofing, spacing, etc.) cannot practically be utilized. The key to providing an effective system is to ensure the surfaces to be protected receive adequate water densities and that the arrangements to activate the system are equally fast acting. By far the highest... 

Amending Directive 2001/5/EC contains several new authorisations including the addition of E 949 hydrogen to annex I, and E 943a butane, E 943b iso-butane and E 944 propane to annex IV for use as vegetable oil pan sprays (professional use only) and as water-based emulsion sprays, quantum satis. E 650 zinc acetate is also added to annex IV for use in chewing gum, max. 1000 mg/kg. 

Fig. 5.8 Analysis of a Narcissus extract by HPLC coupled to the MS-based AChE assay. MS instrument Q-ToF2 (Waters) equipped with a Waters Z-spray electrospray (ESI) source, (a) Total ion current (TIC) (b) product trace (choline) m/z 104 (c) substrate trace (acetylcholine) m/z 146 (d)...

NFPA 11—Standard for Low-Fxpansion Foam NFPA 11A—Standard for Medium- and High-Expansion Foam Systems NFPA 12—Standard on Carbon Dioxide Extinguishing Systems NFPA 12A—Standard on Halon 1301 Eire Extinguishing Systems NFPA 13—Standard for the Installation of Sprinkler Systems NFPA 15—Standard for Water Spray fixed Systems for Fire Protection NFPA 25—Standard for the Inspection, Testingand Maintenance of Water-Based Fire Protection Systems... 

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