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Stearic

SNG Substitute natural gas. soaps Sodium and potassium salts of fatty acids, particularly stearic, palmitic and oleic acids. Animal and vegetable oils and fats, from which soaps are prepared, consist essentially of the glyceryl esters of these acids. In soap manufacture the oil or fat is heated with dilute NaOH (less frequently KOH) solution in large vats. When hydrolysis is complete the soap is salted out , or precipitated from solution by addition of NaCl. The soap is then treated, as required, with perfumes, etc. and made into tablets. [Pg.362]

Lithium hydroxide with 12-hydroxy-stearic acid (or hydrogenated castor oil) they form the family of lithium greases very commonly used for general lubrication and bearing lubrication. [Pg.281]

Sodium hydroxide with stearic acid they constitute the sodium greases, used in the lubrication of bearings under dry conditions and gear trains. [Pg.281]

In the light or medium cuts, the acids are linear as in valeric acid CHg - (CH2)3 - COOH or stearic acid CHg - (CH2)ig - COOH. [Pg.330]

Langmuir also gave needed emphasis to the importance of employing pure substances rather than the various natural oils previously used. He thus found that the limiting area (at the Pockels point) was the same for palmitic, stearic, and cerotic acids, namely, 21 per molecule. (For convenience to the reader, the common names associated with the various hydrocarbon derivatives most frequently mentioned in this chapter are given in Table IV-1.)... [Pg.102]

The limiting compression (or maximum v value) is, theoretically, the one that places the film in equilibrium with the bulk material. Compression beyond this point should force film material into patches of bulk solid or liquid, but in practice one may sometimes compress past this point. Thus in the case of stearic acid, with slow compression collapse occurred at about 15 dyn/cm [81] that is, film material began to go over to a three-dimensional state. With faster rates of compression, the v-a isotherm could be followed up to 50 dyn/cm, or well into a metastable region. The mechanism of collapse may involve folding of the film into a bilayer (note Fig. IV-18). [Pg.116]

Still another manifestation of mixed-film formation is the absorption of organic vapors by films. Stearic acid monolayers strongly absorb hexane up to a limiting ratio of 1 1 [272], and data reminiscent of adsorption isotherms for gases on solids are obtained, with the surface density of the monolayer constituting an added variable. [Pg.145]

Plot the shape of the contact line pinned to a defect using Eq. X-30 for water on polyethylene, stearic acid, and platinum. Assume that the upper cutoff length is 2 mm. How does the shape of the pinned contact line compare with your observations of raindrops on dirty windows ... [Pg.382]

The adsorption of stearic acid from n-hexane solution on a sample of steel powder is measured with the following results ... [Pg.420]

It is known that even condensed films must have surface diffusional mobility Rideal and Tadayon [64] found that stearic acid films transferred from one surface to another by a process that seemed to involve surface diffusion to the occasional points of contact between the solids. Such transfer, of course, is observed in actual friction experiments in that an uncoated rider quickly acquires a layer of boundary lubricant from the surface over which it is passed [46]. However, there is little quantitative information available about actual surface diffusion coefficients. One value that may be relevant is that of Ross and Good [65] for butane on Spheron 6, which, for a monolayer, was about 5 x 10 cm /sec. If the average junction is about 10 cm in size, this would also be about the average distance that a film molecule would have to migrate, and the time required would be about 10 sec. This rate of Junctions passing each other corresponds to a sliding speed of 100 cm/sec so that the usual speeds of 0.01 cm/sec should not be too fast for pressurized film formation. See Ref. 62 for a study of another mechanism for surface mobility, that of evaporative hopping. [Pg.450]

There is a fair amount of work reported with films at the mercury-air interface. Rice and co-workers [107] used grazing incidence x-ray diffraction to determine that a crystalline stearic acid monolayer induces order in the Hg substrate. Quinone derivatives spread at the mercury-n-hexane interface form crystalline structures governed primarily by hydrogen bonding interactions [108]. [Pg.552]

Chemical properties of deposited monolayers have been studied in various ways. The degree of ionization of a substituted coumarin film deposited on quartz was determined as a function of the pH of a solution in contact with the film, from which comparison with Gouy-Chapman theory (see Section V-2) could be made [151]. Several studies have been made of the UV-induced polymerization of monolayers (as well as of multilayers) of diacetylene amphiphiles (see Refs. 168, 169). Excitation energy transfer has been observed in a mixed monolayer of donor and acceptor molecules in stearic acid [170]. Electrical properties have been of interest, particularly the possibility that a suitably asymmetric film might be a unidirectional conductor, that is, a rectifier (see Refs. 171, 172). Optical properties of interest include the ability to make planar optical waveguides of thick LB films [173, 174]. [Pg.560]

The other peaks demonstrate the power of NMR to identify and quantitate all the components of a sample. This is very important for die phannaceutical industry. Most of the peaks, including a small one accidentally underlying the methyl resonance of paracetamol, arise from stearic acid, which is connnonly added to paracetamol tablets to aid absorption. The integrals show diat it is present in a molar proportion of about 2%. The broader peak at 3.4 ppm is from water, present because no attempt was made to dry the sample. Such peaks may be identified either by adding fiirther amounts of the suspected substance, or by the more fiindamental methods to be outlined below. If the sample were less concentrated, then it would also be... [Pg.1442]

MI] Tredgold R H and Winter C S 1981 Tunneling currents in Langmuir-Blodgett monolayers of stearic acid J. Phys. D Appl Phys. 14 LI 85-8... [Pg.2631]

Fig. 7.23 In simulations of stearic add on a hydrophobic surface hydrogen bonding between the head groups is important in controlling the orientation of the molecules [Kim et al, 1994b],... Fig. 7.23 In simulations of stearic add on a hydrophobic surface hydrogen bonding between the head groups is important in controlling the orientation of the molecules [Kim et al, 1994b],...
The term fat is applied to solid esters of fatty acids with glycerol (glycerides) if the fat is liquid at the ordinary temperature, it is conventionally called a fatty oil, vegetable oil or animal oil. The acids which occur most abundantly are palmitic ticid CH3(CHj),4COOH, stearic acid CH3(CH2)isCOOH and oleic acid CH3(CH2),CH=CH(CH2),C00H. Upon hydrolysis, fats yield glycerol and the alkali salts of these acids (soaps) ... [Pg.444]

Formic acid Acetic acid Stearic acid Lactic acid... [Pg.792]

Laurie acid Myristic acid Palmitic acid Stearic acid Arachidic acid... [Pg.1073]


See other pages where Stearic is mentioned: [Pg.168]    [Pg.172]    [Pg.173]    [Pg.295]    [Pg.296]    [Pg.371]    [Pg.371]    [Pg.412]    [Pg.281]    [Pg.281]    [Pg.103]    [Pg.121]    [Pg.151]    [Pg.152]    [Pg.365]    [Pg.446]    [Pg.540]    [Pg.1443]    [Pg.2609]    [Pg.2609]    [Pg.416]    [Pg.416]    [Pg.417]    [Pg.365]    [Pg.395]    [Pg.388]    [Pg.1072]    [Pg.30]    [Pg.461]    [Pg.485]    [Pg.504]   
See also in sourсe #XX -- [ Pg.18 , Pg.89 , Pg.94 , Pg.145 ]




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10- methyl stearic acid

12-Hydroxy stearic acid

12-Nitroxide stearic acid

18-Hydroxy-9,10-epoxy stearic acid

2-Hydroxyethyl ester stearic acid

Acid, stannic stearic

Activation index stearic acid

Alpha-elaeo stearic

Appendix Stearic Acid

Calcium carbonate stearic acid modification

Calcium stearic acid coated

Calcium stearic acid modification

Cholesterol stearic acid

Cocoa butter stearic acid

Compounding ingredients stearic acid

Crude stearic acid

Dihydroxy stearic acid

Doxyl-stearic acid

Effects of Stearic Acid Coating in Composites

Emulsifiers stearic acid

Emulsifying agents stearic acid

Esterification stearic acid

Esterification, by azeotropic distillation of stearic acid with ethanol

Fatty acids stearic acid

Food components stearic acid

Geometry stearic acid

Grades of stearic acid

Granules stearic acid

Infrared spectroscopy stearic acid

Ketone stearic acids

Lubricants stearic acid

Major fatty acids stearic

Methylene stearic acid

Monolayers stearic acid

Of stearic acid

Oils Rich in Palmitic and Stearic Acids

Ointment bases stearic acid

Oxidation of stearic acid

Palmitic and stearic acids

Palmitic, stearic acid esters, mixed

Pearl stearic

Plasticizers stearic acid

Propane stearic acid

Properties of Stearic Acid

Purified stearic acid

Reaction with stearic acid

Rubber grade stearic acid

STEARIC ACID.340(Vol

Saturated fatty stearic

Solids stearic acid adsorption

Solubilizing agents stearic acid

Steady state Stearic acid

Stearamide Stearic acid

Stearate/stearic acid

Stearate/stearic acid synthesis

Stearic Acid Methylester

Stearic Acid and Stearates

Stearic Chlorination

Stearic acid

Stearic acid (CAS

Stearic acid -grafted chitosan

Stearic acid -grafted chitosan oligosaccharide

Stearic acid aluminum dihydroxide salt

Stearic acid aluminum salt

Stearic acid and derivs

Stearic acid and sodium stearate

Stearic acid biosynthesis

Stearic acid calcium salt

Stearic acid chemical structure

Stearic acid chemisorption

Stearic acid cholesterol effect

Stearic acid coated calcium carbonates

Stearic acid coating

Stearic acid coating, phases

Stearic acid crystals

Stearic acid deficiency

Stearic acid deoxygenation

Stearic acid description

Stearic acid desorption

Stearic acid energy yield

Stearic acid esterification reaction

Stearic acid esterified

Stearic acid ethyl ester

Stearic acid films

Stearic acid formula

Stearic acid from

Stearic acid from platinum

Stearic acid functionality

Stearic acid magnesium salt

Stearic acid melting point

Stearic acid modification, effect

Stearic acid modified soy protein isolate

Stearic acid monoester with glycerol

Stearic acid monolayer

Stearic acid monolayer reflectivity

Stearic acid monomolecular films

Stearic acid oxidation

Stearic acid products

Stearic acid properties

Stearic acid reinforcing fillers

Stearic acid salts

Stearic acid series

Stearic acid sodium salt

Stearic acid solubility

Stearic acid spin label

Stearic acid structure

Stearic acid treatment

Stearic acid unit cell

Stearic acid vegetable oils

Stearic acid weathering

Stearic acid zinc salt

Stearic acid, 437 (Table

Stearic acid, absorption

Stearic acid, absorption phospholipid

Stearic acid, aluminium salt

Stearic acid, cerebrosides

Stearic acid, continued

Stearic acid, hydroxylation

Stearic acid, limiting film area

Stearic acid, methyl ester, transesterification

Stearic acid, molecular model

Stearic acid, molecular model structure

Stearic acid, molecular structure

Stearic acid, potassium salts

Stearic acid, starch ester

Stearic acid, stearate absorption

Stearic acid, stearate hydroxylation

Stearic acid, stearate physical properties

Stearic acid, stearin

Stearic acid-coated fillers

Stearic acids characteristics

Stearic add

Stearic anhydride

Stearic candles

Stearic concentration

Stearic fatty acid

Stearic hindrance

Stearic hydrazide

Stearic monoglyceride

Stearic oxidative decarboxylation

Stearic structure, melting point

Synthesis stearic acid

Synthetic waxes stearic acid

Zinc salt of stearic acid

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