Organs typical weight

Typical values for the uptake rate constants of hydrophobic chemicals range between approximately 1000 1 kg da)r for small fish, such as guppy of 0.1 g, and 1301 kg d for larger fish, such as rainbow trout of 750 g. It must be noted that a theoretically better founded relationship for the uptake rate constant does not exclusively rely on weight and K(, , but also includes ventilation rate of the organism, molecmlar weight of the chemical, ambient temperature and others [23,37,45,46]. 

This becomes more aromatic and carbon-rich as it generates petroleum and evolves toward graphite. In contrast, the solvent-extractable lower molecular weight organic materials called bitumen or extractables increase in hydrogen content and progress through compositions typical of cmde oils to those of gas (10). 

Silicone Resins. Sihcone resins are an unusual class of organosdoxane polymers. Unlike linear poly(siloxanes), the typical siUcone resin has a highly branched molecular stmcture. The most unique, and perhaps most usehil, characteristics of these materials are their solubiUty in organic solvents and apparent miscibility in other polymers, including siUcones. The incongmity between solubiUty and three-dimensional stmcture is caused by low molecular weight < 10, 000 g/mol) and broad polydispersivity of most sihcone resins. 

MethylceUulose with a methyl DS less than about 0.6 is alkali-soluble. Erom about 1.6 to 2.4, it is water-soluble (most commercial grades) above 2.4, it is soluble in a wide variety of organic solvents. MethylceUulose solutions in water start to gel at 55° C, independent of molecular weight. The gelation is a function of the DS, rate of heating, and type and amounts of additives such as salts. As the temperature increases, the viscosity initially decreases (typical behavior). When the gelling temperature is reached, the viscosity sharply rises until the flocculation temperature is reached. Above this temperature, the viscosity coUapses. This process is reversible with temperature (75). 

No. 6 fuel oil contains from 10 to 500 ppm vanadium and nickel in complex organic molecules, principally porphyrins. These cannot be removed economically, except incidentally during severe hydrodesulfurization (Amero, Silver, and Yanik, Hydrode.suljurized Residual Oils as Gas Turbine Fuels, ASME Pap. 75-WA/GT-8). Salt, sand, rust, and dirt may also be present, giving No. 6 a typical ash content of 0.01 to 0.5 percent by weight. 

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