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Aliphatic hydrocarbons water

With only few exceptions, most log P programs refer to the octanol-water system. Based on Rekker s fragmental constant approach, a log P calculation for aliphatic hydrocarbon-water partitioning has been reported [96]. Another more recent approach to alkane-water log P and log D is based on the program VolSurf [97]. It is believed that these values may offer a better predictor for uptake in the brain. [Pg.37]

Mannhold, R., Rekker, R. F. The hydrophobic fragmental constant approach for calculating log P in octanol/ water and aliphatic hydrocarbon/water systems. Perspect. Drug Discov. Des. 2000, 18,1-18. [Pg.48]

Rekker, R. E., Mannhold, R., Bijloo, G., De Vries, G Dross, K. The lipophilic behaviour of organic compounds 2. The development of an aliphatic hydrocarbon/ water fragmental system via interconnection with octanol-water partitioning data. Quant. Struct.-Activ. Rel. 1998, 37, 537-548. [Pg.431]

Emulsifying agent useful in highly refined aliphatic hydrocarbon-water systems. [Pg.500]

Rekker, R.F., Mannhold, R., Bijloo, G.J., de Vries, G. and Dross, K. (1998). The Lipophilic Behaviour of Organic Compounds 2. The Development of an Aliphatic Hydrocarbon/Water Fragmental System via Interconnection with Octanol/Water Partitioning Data. Quant.Struct.-AclRelat., 17, 537-548. [Pg.636]

Chem. Descrip. Hard unsat. polyester resin Uses Film-former, raw material for conventional and UV curing, dear and pigmented, gloss and matte aq. coatings Features Wax-free, solv.-free produces films which are brilliant and resist. to scratching, water, alcohols, soivs., household cleaners Properties Sol. in ketones, esters partly sol. in alcohols, aliphatic hydrocarbons water-emulsifiable dens. = 1.12 g/ml (20 C) acid no. 17 05 flash pt. > 100 C < 0.2%. water... [Pg.105]

Properties Yel. brittle amorphous lumps or powd. turpentine-like fresh resinous odor sol. in alcohol, acetone insol. in benzene, aryl and aliphatic hydrocarbons, water sp.gr. 1.05-1.09 m.p. 135-150 C soften, pt. 100-130 C iodine no. 112-141 sapon. no. 145-157 ref. index 1.545 Uses Binder in lacquers and paper/picture varnishes emulsion stabilizer in cosmetics natural flavoring agent in alcoholic beverages in food-pkg. adhesives in food-contact coatings... [Pg.3874]

Physical Properties. Benzene, C H, toluene, C Hj-CH, and petrol (a mixture of aliphatic hydrocarbons, e.g., pentane, hexane, etc.) are colourless liquids, insoluble in and lighter than water. Benzene and toluene, which have similar odours, are not readily distinguishable chemically, and their physical constants should therefore be carefully noted benzene, m.p. 5 (solidifies when a few ml. in a dry test-tube are chilled in ice-water), b.p. 8i toluene, m.p. —93°, b.p. 110°. Petroleum has a characteristic odour. [Pg.393]

Oxonium salt formation. Shake up 0 5 ml. of ether with 1 ml. of cone. HCl and note that a clear solution is obtained owing to the formation of a water-soluble oxonium salt. Note that aromatic and aliphatic hydrocarbons do not behave in this way. In general diaryl ethers and alkyl aryl ethers are also insoluble in cone. HCl. [Pg.396]

These compounds are highly soluble in water. AMP, AMPD, AEPD, and DMAMP are completely miscible in water at 20 °C the solubihty of AB is 250 g/100 mL H2O at 20°C. They are generally very soluble in alcohols, slightly soluble in aromatic hydrocarbons, and nearly insoluble in aliphatic hydrocarbons tris(hydroxymethy1)aminomethane [77-86-1] is appreciably soluble only in water (80 g/100 mL at 20°C) and methanol. [Pg.16]

Dispersion forces are ubiquitous and are present in all molecular interactions. They can occur in isolation, but are always present even when other types of interaction dominate. Typically, the interactions between hydrocarbons are exclusively dispersive and, because of them, hexane, at S.T.P., is a liquid boiling at 68.7°C and is not a gas. Dispersive interactions are sometimes referred to as hydrophobic or lyophobic particularly in the fields of biotechnology and biochemistry. These terms appear to have arisen because dispersive substances, e.g., the aliphatic hydrocarbons, do not dissolve readily in water. Biochemical terms for molecular interactions in relation to the physical chemical terms will be discussed later. [Pg.64]

Polymerization of raw feedstock. Aliphatic hydrocarbon resins. Raw feedstock contains straight-chain and cyclic molecules and mono- and diolefins. The most common initiator in the polymerization reaction is AICI3/HCI in xylene. The resinification consists of a two-stage polymerization in a reactor at 45°C and high pressure (10 MPa) for several hours. The resulting solution is treated with water and passed to distillation to obtain the aliphatic hydrocarbon resins. Several aliphatic hydrocarbon resins with different softening points can be adjusted. [Pg.608]

This has a very high resistance to impact damage, even at subzero temperatures. It has good creep strength in dry conditions up to 115°C but degrades by continuous exposures to water hotter than 65°C. It is resistant to aqueous solutions of acids, aliphatic hydrocarbons, paraffins, alcohols (except methanol), animal and vegetable fats and oils, but is attacked by alkalis, ammonia, aromatic and chlorinated hydrocarbons. [Pg.119]

Styragel columns are compatible with most solvents commonly used in size exclusion chromatography. Exceptions are found on both sides of the polarity scale the use of standard general-purpose Styragel columns with aliphatic hydrocarbons or with alcohols (except hexafluoroisopropanol) and water is generally not recommended. However, it is possible to pack columns in special solvents for special-purpose applications. The interested user should contact Waters for additional information. [Pg.341]

The semicrystalline polyesters of the terephthalate and naphthalate family are resistant to a wide range of chemicals at room temperature, including water, alcohols, ketones, ethers, glycols, chlorinated solvents, aliphatic hydrocarbons, and oils. They are slowly hydrolyzed in boiling water and rapidly degraded in strongly basic or acidic medium. [Pg.45]

The most popular bonded phases are, without doubt, the reverse phases which consist solely of aliphatic hydrocarbon chains bonded to the silica. Reverse phases interact dispersively with solvent and solute molecules and, as a consequence, are employed with very polar solvents or aqueous solvent mixtures such as methanol/water and acetonitrile/water mixtures. The most commonly used reverse phase appears to be the brush type phase with aliphatic chains having four, eight or eighteen carbon atom chains attached. These types of reverse phase have been termed C4, C8 and Cl8 phases respectively. The C8... [Pg.76]

Jensen S, Rosenberg R. 1975. Degradability of some chlorinated aliphatic hydrocarbons in sea water and sterilized water. Water Res 9 659-661. [Pg.272]

Another variation of the preceding method is to apply HPLC to fractionate the cleaned-up aliphatic-aromatic fraction from flash colurim separation of soluble organic matter as it is performed in the Chevron laboratory, for example, as described in Reference 2. A Waters HPLC system equipped with a preparative Whatman Partisil 10 silica column (9.4 X 500 mm), a HPLC pump, and two detectors for separation monitoring (a UV and refractive index detector) are used, giving three fractions of aliphatic hydrocarbons, mono-, di-, and triaromatics and polar compounds. The hrst two fractions are eluted with hexane, whereas polar compounds are eluted with... [Pg.372]

Oxime carbamates have high polarity and solubility in water and are relatively chemically and thermally unstable. They are relatively stable in weakly acidic to neutral media (pH 4-6) but unstable in strongly acidic and basic media. Rapid hydrolysis occurs in strongly basic aqueous solutions (pH > 9) to form the parent oxime/alcohol and methylamine, which is enhanced at elevated temperature. Additionally, oxime carbamates are, generally, stable in most organic solvents and readily soluble in acetone, methanol, acetonitrile, and ethyl acetate, with the exception of aliphatic hydrocarbons. Furthermore, most oxime carbamates contain an active -alkyl (methyl) moiety that can be easily oxidized to form the corresponding sulfoxide or sulfone metabolites. [Pg.1144]

Polyalphaolefin Hydraulic Fluids. The transformation and degradation properties of the polyalphaolefin hydraulic fluids in water will be similar to the mineral oil fluids since they contain similar aliphatic hydrocarbon isomers. [Pg.303]

Polyalphaolefin Hydraulic Fluids. As is the case with mineral oil hydraulic fluids, assessing the presence of polyalphaolefin hydraulic fluids in water by identifying occurrences of the components of these hydraulic fluids is difficult because the aliphatic hydrocarbon isomers in polyalphaolefin hydraulic fluids also are present in mineral oils. Thus, the occurrence of polyalphaolefins in water cannot always be uniquely associated with hydraulic fluid usage. [Pg.307]

Mineral Oil Hydraulic Fluids. Methods are available for analysis of the hydrocarbon components of mineral oil hydraulic fluids (predominantly straight and branched chain alkanes) in environmental samples. Some of these methods are summarized in Table 6-3. In general, water and sediment samples are extracted with a suitable solvent in a Soxhlet extractor (for solid samples) or in separatory funnel or shake flask (for liquid samples) (Bates et al. 1984 Peterman et al. 1980). The extract is cleaned up on silica gel or Florisil columns using a nonpolar solvent to elute the nonpolar alkanes. Analysis is usually performed by GC/MS (Bates et al. 1984 Kawamura and Kaplan 1983 Peterman et al. 1980). Method performance has not been reported, although 82% recovery of aliphatic hydrocarbons was reported for rainwater (Kawamura and Kaplan 1983). [Pg.324]

Serrazanetti GP, Conte LS, Carpene E, et al. 1991. Distribution of aliphatic hydrocarbons in plankton of Adriatic sea open waters. Chemosphere 23 925-938. [Pg.350]

Water-immiscible, volatile, or more likely nonvolatile liquids such as vegetable oils, aromatic and aliphatic hydrocarbons (mineral oil), medium-chain triglycerides, and acetylated glycerides. [Pg.375]


See other pages where Aliphatic hydrocarbons water is mentioned: [Pg.210]    [Pg.9]    [Pg.210]    [Pg.305]    [Pg.210]    [Pg.9]    [Pg.210]    [Pg.305]    [Pg.21]    [Pg.245]    [Pg.341]    [Pg.66]    [Pg.67]    [Pg.37]    [Pg.137]    [Pg.788]    [Pg.72]    [Pg.35]    [Pg.274]    [Pg.376]    [Pg.384]    [Pg.85]    [Pg.162]    [Pg.823]   
See also in sourсe #XX -- [ Pg.29 ]




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Aliphatic hydrocarbons

Hydrocarbon water

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