Color coprecipitation

Raw juice is heated, treated sequentially with lime (CaO) and carbon dioxide, and filtered. This accomplishes three objectives (/) microbial activity is terminated (2) the thin juice produced is clear and only lightly colored and (J) the juice is chemically stabilized so that subsequent processing steps of evaporation and crystalliza tion do not result in uncontrolled hydrolysis of sucrose, scaling of heating surfaces, or coprecipitation of material other than sucrose. 

Wool—Acrylic Fibers. This blend is being used for iadustrial and hand knitting yams. The acryHc fiber is aesthetically similar to wool, iacreases the strength of the yam, and adds bulk to the goods. Special precautions are necessary siace the two fibers are colored with dyes of opposite ionic type. Coprecipitation is prevented with the use of an antiprecipitant. Usually, level dyeing acid dyes are used for the wool portion in combination with the cationic dyes for acryHc fiber. 

Ml Thickener It is a coarse, granular material ranging in color from light tan to brown. Chemically, it is a coprecipitated A1 soap of naphthenic, oleic and palmitic acids in the approx ratio of 1 1 2. The three main disadvantages accruing from the properties of Ml thickener are (1) it is a critical wartime material since it is made from coconuts (2) it is extremely hygroscopic, and the presence of water decreases its ability to form a stable thickened fuel. In addition, the relatively large... 

Rancourt, D.G. Fortin, D. PichlepT Thibault, P.-J. Lamarche, G. Morris, R.V. Mercier, P. H. J. (2001) Mineralogy of natural As-rich hydrous ferric oxide coprecipitate formed by mixing of hydrothermal fluid and sea water Implications regarding surface complexation and color banding in ferrihydrite deposits. Amer. Min. 86 834-851. 

Thorium coprecipitated from acidified sample with Fe(OH)3, clean-up Th by selective solvent extraction, coprecipitated with Al(OH)3 and develop color by Arsenazo III reagent. After color development, coprecipitate Th with LaF3. 

A solution of tetrakis(triphenylphosphine)platinum (1.24 g., 0.001 mole) [Inorganic Syntheses, 11, 105 (1968)] in benzene (10 ml.) is added to a solution of triphenyl phosphite (1.55 g., 0.005 mole) in benzene (5 ml.). The resultant pale-colored solution is filtered, diluted with n-hexane (25 ml.), and cooled overnight at 5°. The white crystalline product is filtered off, extracted with warm n-hexane (25 ml.) to remove coprecipitated tri-phenylphosphine, and dried in vacuo. Yield is 1.2 g. (84%). The product may be further purified by dissolving in the minimum volume of benzene and reprecipitating by addition of n-hexane (m.p. 148-154°). Anal. Calcd. for C72H60Oi2P4Pt ... 

Hagerman-Butler method Complexation with ferric chloride. Original design after precipitation of tannins with BSA and subsequent resolubilization. detection wavelength 510 nm green color with condensed tannins, blue color with hydrolyzable tannins, but color also depends on solvent complexes are unstable, original design monomers coprecipitate 47,116,163... 

Nature of Initial Intermediates and Precursors. - It is well known that during the coprecipitation of Cu-ZnO catalysts the color of the precipitates changes from blue to greenish blue after a certain period, and carbon dioxide evolution is often observed. Little progress has been made in the study on the mechanism that can interpret the above phenomena. 

A solution of 40 ml. (63 g.) of freshly distilled TiCU (b.p. 134-138 °C) in 130 ml. of water is prepared. Most of this solution is then reduced to a slight extent by means of Zn rods or, better, by electrolysis (light-brown color), while 10 ml. kept separately is reduced to the trivalent titanium ion (deep violet color). The reduction is Intended to ensure that all the Iron is present in the form of Fe " ", to avoid hydrolysis and coprecipitation of Fe + with the Ti. The reaction is carried out in dilute oxalic acid. 

The urochromes dissolved in water are precipitated by coprecipitation with aluminium hydroxide. The precipitate is decanted or centrifuged off and dissolved in formic acid. After adding phosphoric acid to eliminate iron coloration, the urochrome content is determined by measurement of the extinction at 380 nm. If humic acids are present, a second extinction measurement is taken at 530 nm and taken into account in the calculation. Instead of calibration with a urochrome reference solution, the urochrome content is calculated by multiplying the "colour value" by an empirical factor. 

Cadmium lithopone n. Pigment red 108 (77202). Range of yellow, orange, and red colors consisting of either cadmium sulfide or cadmium red reduced on barium sulfate. They are usually produced by coprecipitation followed by calcinations. 

In the blood, uric acid is distributed between red cells and serum. The proportion found in each fraction of the blood is determined by the Gibbs-Donnan equilibrium. Two types of methods are available for determining uric acid in blood—colorimetric and enzymic analyses. The colorimetric methods require preliminary precipitation of blood proteins, which entails coprecipitation of urates. In addition, the color tests are never rigidly specific for urates. For these reasons, accurate uric acid determinations are obtained only by treating the serum with uricase. The disappearance of uric acid from the sample can be determined by a spectrophotometric reading at 292 mp before and after enzymic treatment. 

Alkali bromides, chlorides, sulfates, and nitrates interfere only when very small amounts of iodide are to be detected. Bromides have the greatest deleterious effect however, when the amount of bromide is approximately known, small amounts of iodine may still be detected if a comparative test is carried out. Metal salts which give colored aqueous solutions interfere (Fe , UOa, Ni, Cu, Co). Cyanides, mercuric, silver, and manganese salts impair the reaction, as do compounds which reduce Ce. In such cases the difficulty may occasionally be averted by using more concentrated ceric solutions. Under the experimental conditions, barium and strontium salts are precipitated as sulfates, which are colored yellow by coprecipitation of ceric salt. Osmium salts behave similarly to iodides. 

Amounts smaller than 0.15 y manganese per drop may be detected 100 - 150 ml water is treated with a few drops of sodium hydroxide solution, boiled, and filtered. The calcium and magnesium carbonates thus precipitated by the carbonate in the alkali coprecipitate any manganese dioxide formed. The mixture is filtered through a quantitative paper and tested on the paper with benzidine solution. A blue color indicates manganese. As little as 1.2 y manganese (dilution 1 25,000,000) may be detected. 

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