Odor production and release

KONRAD LORENZ On Aggression (1963), p. 53 of original German version, translated by author. 

Chemosignals in vertebrates come from a great variety of sources. These sources include excretions, secretions, material recycled from other organisms, and even from the environment. 

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A variety of chemical products and fabrics are reputed to be antibacterial and to prevent odors and the spread of infection (170). One such finish is based on an organosiUcon quaternary ammonium chloride compound (171). Chemical finishing of cotton has also been directed toward improving soil release (172,173), antistatic treatments (174), and rot resistance (175,176). 

In the United States, about 80% of the 23 million kg of technical PCP produced annually — or about 46% of worldwide production — is used mainly for wood preservation, especially utility poles (Pignatello etal. 1983 Kinzell etal. 1985 Zischke etal. 1985 Choudhury etal. 1986 Mikesell and Boyd 1986 USPHS 1994). It is the third most heavily used pesticide, preceded only by the herbicides atrazine and alachlor (Kinzell et al. 1981). Pentachlorophenol is a restricted-use pesticide and is no longer available for home use (USPHS 1994). Before it became a restricted-use pesticide, annual environmental releases of PCP from production and use were 0.6 million kg to the atmosphere from wood preservation plants and cooling towers, 0.9 million kg to land from wood preservation use, and 17,000 kg to aquatic ecosystems in runoff waters of wood treatment plants (USPHS 1994). There are about 470 wood preservative facilities in the United States, scattered among 45 states. They are concentrated in the South, Southeast, and Northwest — presumably due to the availability of preferred timber species in those regions (Cirelli 1978). Livestock facilities are often constructed of wood treated with technical PCP about 50% of all dairy farms in Michigan used PCP-treated wood in the construction of various components of livestock facilities (Kinzell et al. 1985). The chemical is usually applied to wood products after dilution to 5% with solvents such as mineral spirits, No. 2 fuel oil, or kerosene. More than 98% of all wood processed is treated with preservative under pressure about 0.23 kg of PCP is needed to preserve 1 cubic foot of wood (Cirelli 1978). Lumber treated with PCP retains its natural appearance, has little or no odor, and can be painted as readily as natural wood (Wood et al. 1983). 

Nowadays the electronic appliances used for entertainment, telecommunications and data processing are widespread in daily life. Typical examples include televisions, video recorders, hi-fi systems and fax machines, not to mention computers with their peripherals such as monitors and printers, scanners and copiers. These devices are predominantly made of polymeric components and materials which might contain additives, such as flame retardants and plasticizers (Wensing, Uhde and Salthammer, 2005) to obtain specific desired properties. In addition, there will also be chemical residues from production and processing aids, such as residual monomers and solvents. Especially under operating conditions these compounds can be released from electronic equipment into indoor air due to the heating-up of the device interior. In many cases, such emissions can be monitored via simple odor tests (Walpot, 1996). 

Dictyopterene B (1) is one of the polyacetate-derived cyclopropane-containing natural products and is isolated from the essential oil of brown algae Dictyopteris plagiogramma and D. australis. This tri-olefinic cyclopropane is a sex pheromone released by the female plants to attract male gametes. This unusual Cn hydrocarbon along with other Dicyopteris constituents has a characteristic odor associated with ocean beaches. A second... 

Nitromethane is a colorless, oily liquid with a moderately strong, somewhat disagreeable odor. Production of nitromethane and its use as a solvent, fuel additive stabilizer for halogenated alkanes and intermediates, may result in its release into the environment, principally the atmosphere. Human exposure to nitromethane may additionally occur via dermal contact and accidental ingestion. 

Vinyl chloride is a colorless gas with a mild, sweet odor. It is a manufactured substance that is used to make polyvinyl chloride (PVC) for a variety of plastic products, including pipes, wire coatings, and upholstery. Burning these products will release dangerous amounts of Vinyl Chloride. 

Changes in color or odor, production or absorption of heat or light, gas release, and formation of a precipitate are all observable macroscopic changes that indicate that a chemical reaction may have occurred. 

Partial proteolysis of soybean proteins with endopeptidases has been used to remove flavor compounds and related fatty materials from soybean curd and defatted soybean flour (21). Certain soybean protein concentrates possess an undesirable beany and oxidized flavor. Treatment of soybean curd and defatted soybean flour with endopeptidases such as aspergillopeptidase A released off-flavor compounds such as 1-hexanal and 1-hexanol which could be removed from the hydrolysate by solvent extraction. The enzymically digested products had less odor, taste, and color than the starting material and were more stable to oxidative deterioration. 

Nitromethylidynetrimethanol Nitr-otris(hydroxymethyl)methane NSC 17675 S.S.T Sump Saver Tablets Trihydroxymethylnitromethane Trimethyl-olnitromethane Tris-Nitro Tris(hydroxy-methyl)nitro-methane. Antibacterial agent, preservative for water treatment, metalworking fluids, oil production, de-odorizing formaldehyde releaser. Used as a bactericide in pesticide products and consumer products, building materials or furnishings. Registered by EPA as an antimicrobial and disinfectant. Crystals mp = 165° bp dec very soluble in H2O (220 g/100 ml), EtOH, EtsO. Dow Chew. U.S.A. Hess Clark Inc. Whittaker Clark Daniels. 

Monochlorobenzene and 1,2-dichlorobenzene are both colorless, flammable hquids with a sweet, penetrating odor. These are soluble in benzene and alcohols, but are insoluble in water. The vapors are heavier than air and may travel a considerable distance from the source of evaporation. Ignition and flashback to the source may lead to a fire, releasing in toxic and corrosive gases. Monochlorobenzene is a process solvent for methylene diisocyanate, the latter being used as a solvent in adhesives, polishes, waxes, pharmaceutical products, and natural rubber. 

To make natto, soybeans, preferably small seeded, are washed and soaked overnight. The soaked beans are then steamed for 30 min, drained, and cooled to -40°C. Traditionally, the treated soybeans are wrapped with rice straw and set in a warm place for 1-2 days. Rice straw is credited for not only supplying the fermenting microorganism, Bacillus natto, but also absorbing the unpleasant odor of ammonia released from natto and imparting the aroma of straw to the product. 

The temporal pattern of odor emission can also show marked periodicity on either a short timescale (milliseconds) or a longer one (hours or days). Scent production may occur on a short timescale such that odor quanta are produced and released discretely. For example, some species of female moths have been reported to produce odor puffs rather than steady odor production. Odors used for defense, such as the spray secretions of skunks or bombardier beetles, may last only a few seconds. On longer timescales, the scent emission of pheromones for some organisms may follow a temporal pattern that correlates with diurnal phases or with specific periods in the reproductive cycles of individuals. Several studies of flowering plants have shown that floral scents are emitted for hours during those... 

Floral scents are often complex blends of several compounds. These are mainly fatty-acid derivatives, benzenoids, phenylpropanoids, isoprenoids, nitrogen-and sulfur-containing compounds. Knudsen et al. s (1993) comprehensive review of floral odors reported floral scents with as few as three compounds and as many as several hundred. A study of moth-pollinated flowers from the Nyctaginaceae reported as many as 77 compounds in floral scent and as few as one. Studies that have focussed on identifying the site of volatile production in flowers report that they are produced mostly in the petals. Volatiles are both synthesized and released by the epidermal cells or by special glandular trichomes on the petal surface. Other studies have shown that the odor of pollen is also part of the odor signal. ... 

Microcapsules with impermeable walls are used in products where isolation of active substances is needed, followed by a quick release under defined conditions. The effects achieved with impermeable microcapsules include separation of reactive components, protection of sensitive substances against environmental effects, reduced volatility of highly volatile substances, conversion of liquid ingredients into a solid state, taste and odor masking, and toxicity reduction. 

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