Odorant agent

Phospholipases of type CP are activated by Gq proteins which conmumicate themselves with various 7-hehx transmembrane receptors. The initiating external signals are diverse (see Fig. 5.14) and include hormones, neurohormones and sensory signals such as odorous agents and light (in non-vertebrates). 

They are normally odourless, and so have an odorizing agent added to draw attention to leaks. 

This compound proved to be the most powerful odorant agent in polyether polyols. Even in trace amounts, this substance confers an unpleasant odour to polyether polyols. The formation of this compound takes place in the purification step, in acidic media, involving the terminal propenyl-ether groups (in fact vinyl ether groups are very sensitive to acidic attack). The probable mechanism is the following cationic cyclisation ... 

With most industrial activities, the high concentration of chemicals, by products or wastes, can result in high levels of associated odour. This is particularly of concern with food processing, tannery processes and the use or production of sulphur-containing compounds such as hydrogen sulphide. It is a particularly difficult class of pollution to deal with as individual senses vary. In addition, the levels at which odorous agents are sensed, whilst a nuisance, may not be toxic. ... 

Odor 6-d9r [ME odour, fr. ME, fr. L odor, akin to L olere to smell, Gk ozein to smell, osme smell, odor] (13c) n. A reaction that is manifested by a physiological sensation due to physical contact with odorant agent molecules and the human olfactory nervous system. 

Microencapsulation is a necessity for active ingredients of poor stability such as odor agents. Some of the biggest challenges in this field are controlled release of fragrances and their long-lasting perceptions (Pena et al., 2012). 

Emulsives are solutions of toxicant in water-immiscible organic solvents, commonly at 15 ndash 50%, with a few percent of surface-active agent to promote emulsification, wetting, and spreading. The choice of solvent is predicated upon solvency, safety to plants and animals, volatility, flammabiUty, compatibihty, odor, and cost. The most commonly used solvents are kerosene, xylenes and related petroleum fractions, methyl isobutyl ketone, and amyl acetate. Water emulsion sprays from such emulsive concentrates are widely used in plant protection and for household insect control. 

Iodine trichloride [865-44-17, ICl, mol wt 233.39, 54.40% I, is a yellow or brownish powder. It is pungent and has a very irritating odor. It decomposes at 77°C iato ICl and CI2. It is prepared by adding finely powdered iodine to an excess of Hquid chlorine. It is used as a chlorinating and oxidising agent (120). 

Fig. 2. Odor masking (a) how masking agents work, and (b) masking curve for tobacco odor, where ( ) is perceived odor strength (treated) (B) is...

Liquid Fabric Softeners. The principal functions of fabric softeners are to minimize the problem of static electricity and to keep fabrics soft (see Antistatic agents). In these laundry additives, the fragrance must reinforce the sense of softness that is the desired result of their use. Most fabric softeners have a pH of about 3.5, which limits the materials that can be used in the fragrances. For example, acetals cannot be used because they break down and cause malodor problems in addition, there is the likelihood of discoloration from Schiff bases, oakmoss extracts, and some specialty chemicals. Testing of fragrance materials in product bases should take place under accelerated aging conditions (eg, 40°C in plastic bottles) to check for odor stabiUty and discoloration. 

Monomers such as aUyl methacrylate and diaUyl maleate have appUcations as cross-linking and branching agents selected especiaUy for the different reactivities of their double bonds (90) some physical properties are given in Table 8. These esters are colorless Uquids soluble in most organic Uquids but htde soluble in water DAM and DAF have pungent odors and are skin irritants. 

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