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Alcohol contaminated surface

Petroleum spillages can be removed from water surfaces more efficiently with the following detergent mixture [1692], which contains mainly oxyethyl-ate fatty Cio to C20 alcohols and additional oxyethylated fatty Cn to Cyj acids with an oxyethylene chain length of one to two units. It is used in the form of an aqueous 20% to 25% emulsion, which is sprayed onto a contaminated surface. [Pg.307]

Aeration in the field wash contaminated surfaces with a 5% solution by weight of sodium hydroxide in 95% alcohol or strong soda ash solution. [Pg.146]

In reviewing the intrinsic electrochemical behavior of nonaqueous systems, it is important to describe reactions of the most common and unavoidable contaminants. Some contaminants may be introduced by the salts (e.g., HF in solutions of the MFX salts M = P, B, As, etc.). Other possible examples are alcohols, which can contaminate esters, ethers, or alkyl carbonates. We examined the possible effect of alcoholic contaminants such as CH3OH in MF and 1,2-propylenegly-col at concentrations of hundreds of ppm in PC solutions. It appears that the commonly used ester or alkyl carbonate solvents are sufficiently reactive (as described above), and so their intrinsic reactivity dominates the surface chemistry if the concentration of the alcoholic contaminant is at the ppm level. We have no similar comprehensive data for ethereal solutions. However, the most important contaminants that should be dealt with in this section, and which are common to all of these solutions, are the atmospheric ones that include 02, H20, and C02. The reduction of these species depends on the electrode material, the solvent used, and their concentration, although the cation plays the most important role. When the electrolyte is a tetraalkyl ammonium salt, the reduction products of H20, 02 or C02 are soluble. As expected, reduction of water produces OH and... [Pg.178]

Adhesion to plasticized PVC is often poorly effective because migrating plasticizer contaminates surfaces. In this case, pretreatment comprises cleaning with a ketone solvent such as acetone. Polystyrene, nylon, melamine-formaldehydes and polyesters can be pretreated by abrading with an emery cloth prior to cleaning with an alcohol. The effectiveness of all surface treatments decrease rapidly with time, so it is necessary to both modify and adhere within a short period. [Pg.217]

Both the hquid and cured 2-cyanoacryhc esters support combustion. These adhesives should not be used near sparks, heat, or open flame, or ia areas of acute fire ha2ard. Highly exothermic polymerization can occur from direct addition of catalytic substances such as water, alcohols, and bases such as amines, ammonia, or caustics, or from contamination with any of the available surface activator solutions. [Pg.179]

Povidone—iodine is a brown, water-soluble powder containing approximately 10% iodine. However, the amount of free iodine, which is responsible for the antimicrobial activity, is low in a concentrated solution, but is released as the solution is diluted (41). Concentrated solutions have actually been contaminated with bacteria (42). For use as an antiseptic, povidine—iodine is diluted with water or alcohol to a concentration of 1% iodine. Detergents are added if it is used as a surgical scmb. lodophors are important as broad-spectmm antiseptics for the skin, although they do not have the persistent action of some other antiseptics. They are also used as disinfectants for clinical thermometers that have been used by tuberculous patients, for surface disinfection of tables, etc, and for clean equipment in hospitals, food plants, and dairies, much as chlorine disinfectants are used. [Pg.123]

All standard cleaning processes for silicon wafers are performed in water-based solutions, with the exception of acetone or (isopropyl alcohol, IPA) treatments, which are mainly used to remove resist or other organic contaminants. The most common cleaning procedure for silicon wafers in electronic device manufacturing is the deionized (DI) water rinse. This and other common cleaning solutions for silicon, such as the SCI, the SC2 [Kel], the SPM [Ko7] and the HF dip do remove silicon from the wafer surface, but at very low rates. The etch rate of a cleaning solution is usually well below 1 nm min-1. [Pg.24]

If the ITO-coated side of the electrode does not have a purple sheen, then the electrode is either dirty or damaged. The best way to clean an ITO electrode is with a low-molecular-weight alcohol such as isopropyl alcohol (IPA), which does not adsorb to the oxide layers. Some modem laboratories have advanced facilities for burning off the surface contaminants by using a low-pressure plasma. Few analysts would employ ITO-coated electrodes if they always required such stringent conditions prior to routine analyses. [Pg.279]

Place the dead or the anaesthetised mouse on its back or right side on a clean surface. Wipe the abdomen and left side thoroughly with 70% alcohol to clean it off and to wet the fur — this is not going to sterilise the animal s surface, but as long as the spleen does not touch the surface, it will not result in contamination. [Pg.55]

The effectiveness of the method is most probably based on the fact that alkyl hypochlorite is formed at the oil/water interface where the cosurfactant alcohol resides. The oxidation that follows takes place either inside or on the surface of oil droplet. The rate of the reaction can result from a large hydrocarbon/water contact area permitting interaction between oil-soluble sulfide with interfacial cosurfactant that served as an intermediary. An extension ofthis procedure to mustard deactivation has also been proposed [20b]. Such systems could be also applied to the degradation of several environmentally contaminating materials The formation of microemulsions, micelles and vesicles is promoted by unfavourable interactions at the end sections of simple bilayer membranes. There is no simple theory of solute-solvent interactions. However, the formation of... [Pg.73]

Dark adsorption measurements made for a variety of compounds by d Hen-nezel and Ollis [47] displayed a considerable range in the amount of material adsorbed onto TiO2 catalyst surfaces. For gas-phase contaminant concentrations of 50 mg/m and a relative humidity of 7%, dark adsorption measurements for aldehydes and alcohols show approximately 10 times more material adsorbing than do aromatic contaminants (Table 1). Similarly, adsorption isotlierms gener-... [Pg.257]

Most photocatalytic studies conducted at low aromatic concentrations report no detectable concentrations of gas-phase intermediates [12,17,18]. Traces of intermediates may be present in the gas phase, but at levels below the detection limits of the analytical instruments employed in these studies. There is evidence, however, for either reaction intermediates or reaction by-products on the catalyst surface, even at these low concentrations. Catalyst discoloration, typically a yellowish or brownish color, is often reported following the photocatalytic oxidation of aromatic contaminants at low to moderate gas-phase concentrations [3,4,7,17,52]. These intermediates or reaction by-products may be largely trapped on the catalyst surface by the higher affinity of oxygenated species, like alcohols and aldehydes, for TiO, surfaces when compared to the aromatic parent compounds. [Pg.262]

HaS or HI, so as to form lead carbonate, sulfide or iodide oidy on the surface without penetration into the crystal (Ref 22). This treatment will unquestionably reduce the efficiency of LA because it will be contaminated by inert materials l)Solubiliry of LA in water or in 50% alcohol was detd as described in item VII F tinder Lead Azide Plant Analytical Procedures In addn to above listed tests, the various LA s were loaded in M47 caps as intermediate chges together with NOLNo 130 as a primary chge and RDX as a base chge and subjected to the following tests given in the Purchase Description PA-PD-202, with Rev 1 dated 30 Sept 1952 and Amend 1 dated 27 Jan 1953 ... [Pg.562]


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See also in sourсe #XX -- [ Pg.99 ]




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