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Quaternary consumers

We humans eat at all trophic levels. When we eat such things as fruits, vegetables, or the grains shown in Figure 15-2, we are primary consumers when we eat beef or other meat from herbivores, we are secondary consumers. When we eat fish like trout or salmon, which eat insects and other small animals, we are tertiary or quaternary consumers. Our great and growing numbers, however, are possible only because of our ability to ear as primary consumers. [Pg.521]

Was this youT answeT Sharks feed on fish and marine mammals, which makes them secondary, tertiary, or quaternary consumers. Phytoplanktonfeeding gray whales, however, are primary consumers. When an orca feeds on a shark, it is eating at a higher trophic level than when it feeds on a gray... [Pg.522]

The easier elimination of pyridine compared to quinoline-4 may be related to the pK value of 4-methylthiazole, which is between those of lepidine and 2-picoline (25. 55). This reaction explains also why a neutrodimethine cyanine is obtained with such good yields when reacting together a quaternary salt, ketomethylene, and o-ester in a basic medium. As the reaction proceeds, the trimethine cyanine is attacked by the ketomethylene. The resulting 2-methyl quaternary salt is transformed into trimethine cyanine, consuming the totality of the ketomethylene (1, p. 512 661). The mesosubstituted neutrodimethine cyanine is practically pure. [Pg.62]

There are a vast number of quaternary ammonium compounds or quaternaries (1). Many are naturally occurring and have been found to be cmcial in biochemical reactions necessary for sustaining life. A wide range of quaternaries are also produced synthetically and are commercially available. Over 204,000 metric tons of quaternary ammonium compounds are produced aimuaHy in the United States (2). These have many diverse appHcations. Most are eventually formulated and make their way to the marketplace to be sold in consumer products. AppHcations range from cosmetics (qv) to hair preparations (qv) to clothes softeners, sanitizers for eating utensils, and asphalt emulsions. [Pg.374]

There are two reasons why the concentration of quaternaries is beheved to remain at a low level in sewage treatment systems. First, quaternaries appear to bind anionic compounds and thus are effectively removed from wastewater by producing stable, lower toxicity compounds (205). Anionic compounds are present in sewer systems at significantly higher concentrations than are cations (202). Second, the nature of how most quaternaries are used ensures that their concentrations in wastewater treatment systems are always relatively low but steady. Consumer products such as fabric softeners, hair conditioners, and disinfectants contain only a small amount of quaternary compounds. This material is then diluted with large volumes of water during use. [Pg.379]

The single largest market for quaternary ammonium compounds is as fabric softeners. In 1993 this market accounted for over 50,000 metric tons of quaternaries in the United States (235). Consumption of these products is increasing at an annual rate of about 2—3%. The hair care market consumed over 9000 metric tons of quaternary ammonium compounds in 1992 (236). The annual consumption for organoclays is estimated at 12,700 metric tons (237). Esterquats have begun to gain market share in Western Europe and growth is expected to continue. [Pg.382]

Miscellaneous Derivatives. Other derivatives of toluene, none of which is estimated to consume more than ca 3000 t (10 gal) of toluene aimuaHy, are mono- and dinitrotoluene hydrogenated to amines ben2otrich1 oride and chlorotoluene, both used as dye intermediates / 7-butylben2oic acid from / 7-butyltoluene, used as a resin modifier dodecyltoluene converted to a ben2yl quaternary ammonium salt for use as a germicide and biphenyl, obtained as by-product during demethylation, used in specialty chemicals. Toluene is also used as a denaturant in specially denatured alcohol (SDA) formulas 2-B and 12-A. [Pg.192]

Nearly all uses and appHcations of benzyl chloride are related to reactions of the active haUde substituent. More than two-thirds of benzyl chloride produced is used in the manufacture of benzyl butyl-phthalate, a plasticizer used extensively in vinyl flooring and other flexible poly(vinyl chloride) uses such as food packaging. Other significant uses are the manufacture of benzyl alcohol [100-51-6] and of benzyl chloride-derived quaternary ammonium compounds, each of which consumes more than 10% of the benzyl chloride produced. Smaller volume uses include the manufacture of benzyl cyanide [140-29-4], benzyl esters such as benzyl acetate [140-11-4], butyrate, cinnamate, and saUcylate, benzylamine [100-46-9], and benzyl dimethyl amine [103-83-8], and -benzylphenol [101-53-1]. In the dye industry benzyl chloride is used as an intermediate in the manufacture of triphenylmethane dyes (qv). First generation derivatives of benzyl chloride are processed further to pharmaceutical, perfume, and flavor products. [Pg.61]

Thus quaternized thiazoles (170) consume two equivalents of OH on titration because the pseudo bases (171) ring open to (172), which form anions (173). Quaternized oxazoles (174) are readily attacked by hydroxide to give open-chain products such as (175) (74AHC(17)99), and quaternized 1,3,4-oxadiazoles behave similarly. Quaternary isothiazoles (e.g. 176) are cleaved by hydroxide (72AHC(l4)l), as are 1,2,4-thiadiazolium salts (177 178). [Pg.63]

The aromatic rings in the protein absorb ultraviolet light at an absorbance maximum of 280 nm, whereas the peptide bonds absorb at around 205 nm. The unique absorbance property of proteins could be used to estimate the level of proteins. These methods are fairly accurate with the ranges from 20 p,g to 3 mg for absorbance at 280 nm, as compared with 1 to 100 p,g for 205 nm. The assay is non-destructive as the protein in most cases is not consumed and can be recovered. Secondary, tertiary and quaternary structures all affect absorbance therefore, factors such as pH, ionic strength, etc can alter the absorbance spectrum. This assay depends on the presence of a mino acids which absorb UV light (mainly tryptophan, but to a lesser extent also tyrosine). Small peptides that do not contain such a mino acids cannot be measured easily by UV. [Pg.16]

Kemper JM, Wale SS, Mitch WA (2010) Quaternary amines as nitrosamine precursors a role for consumer products Environ Sci Technol 44 1224-1231... [Pg.129]

Besides monitoring bulk solution qualities by conventional analytical methods, measurement of the phase transition may also be warranted. Slight differences in the nature of the formulation owing to aging, undetected by typical analytical methods, may influence the phase transition of the product formulation. For example, absorption of carbon dioxide from the air over an extended time period may cause a pH shift, consume one component of a buffering system, or promote degradation. For a peptide or protein with both a hydrophilic and hydrophobic nature, alterations to desired secondary, tertiary, or quaternary... [Pg.351]

Quaternary ammonium compounds are the next largest group of non-durable antistats. The most widely used are ditallowdimethylammonium chloride and dihydrogenated tallowdimethylammonium chloride (Fig. 10.2). These are common ingredients in laundry and dryer applied consumer softeners. Like many other cationic materials, cationic antistats have an affinity for textile fibres and can be applied by exhaustion processes. [Pg.124]


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See also in sourсe #XX -- [ Pg.520 , Pg.521 ]

See also in sourсe #XX -- [ Pg.520 , Pg.521 ]




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