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Acidic aerosols

A third screening smoke-type is white phosphoms [7723-14-0] (WP), P (see Phosphorus and THE phosphides), which reacts spontaneously with air and water vapor to produce a dense cloud of phosphoms pentoxide [1314-56-3]. An effective screen is obtained as the P2O5 hydrolyzes to form droplets of dilute phosphoric acid aerosol. WP produces smoke in great quantity, but it has certain disadvantages. Because WP has such a high heat of combustion, the smoke it produces from bulk-filled munitions has a tendency to rise in pillarlike mass. This behavior too often nullifies the screening effect, particularly in stiU air. Also, WP is very brittle, and the exploding munitions in which it is used break it into very small particles that bum rapidly. [Pg.401]

Materials The damage that air pollutants can do to some materials is well known ozone in photochemical smog cracks rubber, weakens fabrics, and fades dyes hydrogen sulfide tarnishes silver smoke dirties laundry acid aerosols ruin nylon hose. Among the most important effects are discoloration, corrosion, the soiling of goods, and impairment of visibility. [Pg.2174]

The major effects of air pollution on fabrics are soiling and loss of tensile strength. Sulfur oxides are considered to cause the greatest loss of tensile strength. The most widely publicized example of this type of problem has been damage to women s nylon hose by air pollution, described in newspaper accounts. The mechanism is not understood, but it is postulated that fine droplets of sulfuric acid aerosol deposit on the very thin nylon... [Pg.130]

Consider a lake with a smaU watershed in a forest ecosystem. The forest and vegetation can be considered as an acid concentrator. SO2, NO2, and acid aerosol are deposited on vegetation surfaces during dry periods and rainfalls they are washed to the soil floor by low-pH rainwater. Much of the acidity is neutralized by dissolving and mobilizing minerals in the soil. Aluminum, calcium, magnesium, sodium, and potassium are leached from the soil into surface waters. The ability of soils to tolerate acidic deposition is very dependent on the alkalinity of the soil. The soil structure in the... [Pg.152]

Atmospheric particulates (sea salt, carbonaceous soot, and sulfuric acid aerosols) are known to provide a condensed phase for conq>lex heterogeneous chemistry to occur. Although the presence of atmospheric particulates are known to alter trace gas concentrations, details of the specific chemical mechanisms for condensed phase chemistry have not been identified. [Pg.10]

A portion of nitrogen dioxide in the atmosphere is converted to nitric acid (HNO3) and ammonium salts. Nitrate aerosol (acid aerosol) is removed from the atmosphere... [Pg.22]

Sulfur oxides (SO,) are compounds of sulfur and oxygen molecules. Sulfur dioxide (SO2) is the predominant form found in the lower atmosphere. It is a colorless gas that can be detected by taste and smell in the range of 1, (X)0 to 3,000 uglm. At concentrations of 10,000 uglm , it has a pungent, unpleasant odor. Sulfur dioxide dissolves readily in water present in the atmosphere to form sulfurous acid (H SOj). About 30% of the sulfur dioxide in the atmosphere is converted to sulfate aerosol (acid aerosol), which is removed through wet or dry deposition processes. Sulfur trioxide (SO3), another oxide of sulfur, is either emitted directly into the atmosphere or produced from sulfur dioxide and is readily converted to sulfuric acid (H2SO4). [Pg.38]

Health effects attributed to sulfur oxides are likely due to exposure to sulfur dioxide, sulfate aerosols, and sulfur dioxide adsorbed onto particulate matter. Alone, sulfur dioxide will dissolve in the watery fluids of the upper respiratory system and be absorbed into the bloodstream. Sulfur dioxide reacts with other substances in the atmosphere to form sulfate aerosols. Since most sulfate aerosols are part of PMj 5, they may have an important role in the health impacts associated with fine particulates. However, sulfate aerosols can be transported long distances through the atmosphere before deposition actually occurs. Average sulfate aerosol concentrations are about 40% of average fine particulate levels in regions where fuels with high sulfur content are commonly used. Sulfur dioxide adsorbed on particles can be carried deep into the pulmonary system. Therefore, reducing concentrations of particulate matter may also reduce the health impacts of sulfur dioxide. Acid aerosols affect respiratory and sensory functions. [Pg.39]

Add Aerosol acidic liquid or solid particles that are small enough to become airborne. High concentrations of acid aerosols can be irritating to the lungs and have been associated with some respiratory diseases, such as asthma. [Pg.515]

Sulfuric acid (H1SO4) and ammonium bisulfate (NH4HSO4) contribute importantly to ambient acid aerosols, particularly in geographic locations where sulfur-rich coal is used for power plant fuel, such as the eastern United States.Studies on animals and human subjects have shown that H2SO4 and NH4HSO4 alter mucociliary transport in a dose-dependent fashion and... [Pg.225]

Airstream neutralization of acid aerosols by NH3 present in the airway-lumen reduces the health risk associated with acid particles by reducing the acid concentration prior to particle deposition.- In addition, the liquid lining of the respiratory tract probably acts as a chemical buffer," further reducing the health hazard posed by inspired acid particles. Principal factors controlling airstream neutralization of acid aerosols, which is considered to be a diffusion-limited process, are particle surface area, and particle... [Pg.227]

Larson, T. V., Frank, R., Covert, D..S., Efolub, D., and Morgan, M.S. (1982). Measurements of respiratory ammonia and chemical neutralization of inhaled sulfuric acid aerosol in anesthetized dogs. Am. Rev. Respir. Dis. 125, 502-506. [Pg.232]

Norwood, D. M., Wainman, T., Lioy, P. J., and Waldman, J. M. (1992). Breath ammonia depletion and its relevance to acidic aerosol exposure studies. Arch, of Fa-wtron. Health 47, 309-313. [Pg.232]

Utell, M. J. (1985). Effects of inhaled acid aerosols on lung mechanics an analysis of human exposure studies. Environmental Health Perspect. 63, 39-44. [Pg.233]

Cocks, A, T, and McElroy, W. J. (1984). Modeling studies of the concurrent growth and neutralization of sulfuric acid aerosols under conditions in the human airways. Eimironmefital Res. 35, 79-96. [Pg.233]

TI8. Schlesinger, R. B. (1989). Factors affecting the response of lung clearance systems to acid aerosols role of exposure concentration. E.nviron. Health Perspect. 79, 121-126. [Pg.233]

Two other principles that have been made commercially available are (11 rhe reaction between pyrosulfuric acid (H2S2O7) and water (water vapor in air) to form sulfuric acid aerosol and (2) rhe reaction between ritaiJium tetrachloride (TiCl4) and water to form titanium dioxide (TiO,) and hydrogen chloride il Id), higure 12.5 shows two different hand-held, disposable smoke emitters. [Pg.1113]

If the reaction is between two gas-phase species, then this reaction could be a source of cloud condensation nuclei, or simply a means to neutralize an acidic aerosol. Although there are some questions concerning the measurement of atmospheric HNO3, (Lawson, 1988) most measurements indicate that gaseous HNO3 concentrations predominate over particle NOi". [Pg.323]

H2CO3 (carbonic acid) aqueous phase HC2H3O2 (acetic acid) aqueous, gas phases HCHOz (formic acid) aqueous, gas phases H2C2O4 (oxalic acid) aerosol particles solid phase RCCX3H (many carboxylic acids)... [Pg.423]

H2SO4 (sulfuric acid) aerosol, aqueous phases H2SO3 (sulfurous acid) aqueous phase... [Pg.423]

CH3SO3H (from oxidahon of (CH3)2S, methane sulfonic acid) aerosol, aqueous phases... [Pg.423]

Information on the excretion of americium after dermal exposure in humans or animals is extremely limited. Some qualitative information is available from an accidental exposure in which a worker received facial wounds from projectile debris and nitric acid during an explosion of a vessel containing 241 Am (McMurray 1983). The subject also inhaled 241Am released to the air as dust and nitric acid aerosols, which was evident from external chest measurements of internal radioactivity thus, excretion estimates reflect combined inhalation, dermal, and wound penetration exposures (Palmer et al. 1983). Measurements of cumulative fecal and urinary excretion of241 Am during the first years after the accident, and periodic measurements made from day 10 to 11 years post accident indicated a fecal urine excretion ratio of approximately 0.2-0.3, although the ratio was approximately 1 on day 3 post accident (Breitenstein and... [Pg.71]

Concentrated hydrochloric acid is highly corrosive. Hydrochloric acid is primarily a concern in its aerosol form. Acid aerosols have been implicated in causing and exacerbating a variety of respiratory ailments. Dermal exposure and ingestion of highly concentrated hydrochloric acid can result in corrosivity. There is currently no evidence to suggest that this chemical is carcinogenic. [Pg.144]


See other pages where Acidic aerosols is mentioned: [Pg.495]    [Pg.193]    [Pg.193]    [Pg.194]    [Pg.386]    [Pg.399]    [Pg.523]    [Pg.2382]    [Pg.67]    [Pg.146]    [Pg.150]    [Pg.176]    [Pg.220]    [Pg.225]    [Pg.227]    [Pg.228]    [Pg.228]    [Pg.228]    [Pg.233]    [Pg.233]    [Pg.86]    [Pg.332]    [Pg.60]    [Pg.67]    [Pg.1202]   
See also in sourсe #XX -- [ Pg.67 ]




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Acid aerosol neutralization

Acid aerosol, description

Acid aerosols exposure

Acid aerosols sulfates

Acidic aerosol exposure

Acidic sulfate aerosols

Acidity, in atmospheric aerosol

Acids Aerosols

Acids Aerosols

Acrylic acid Aerosols

Aerosol acidity

Aerosol acidity

Aerosol formation, sulfuric acid

Aerosol strong acid content

Exposure to acid aerosols

Humic acids, aerosol

Smog Sulfur Dioxide, Acidic Aerosols, and Soot

Soluble acid aerosols

Strong acid content, atmospheric aerosol

Strong acid content, atmospheric aerosol particles

Sulfuric acid aerosols

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