Tannic acid solution

Gerbsaure /. tannic acid. -Idsung, /. tannic acid solution, -messer, m. tannometer, bark-ometer. 

Potassium sulfide Solution S s Tannic acid Solution S s... 

Lund s Reaction.1—This is based on the determination of the albuminous substances precipitable by tannic acid. 10 c.c. of the solution prepared as in (2) are treated in a graduated 50 c.c. tube with 5 c.c. of 0 5% tannic acid solution and made up with water to 40 c.c. After careful shaking, the tube is closed with a cork and left for 24 hours, when the volume of the precipitate collected at the bottom of the tube is read. With pure honey the volume is 1-4 c.c., whilst with artificial honey either no precipitate or only a trace is formed. 

If the skin to be tanned is brought between the cathode and anode in a dilute tannic-acid solution, a migration of the colloidally dissolved tannic acid takes place through the skin from the positive to the negative electrode. By a regular slow change of the "current direction the tannic-acid solution can be pressed into the pores of the skin and thus a considerable saving in time is accomplished.2... 

Alternatively, drop-reaction paper treated with 2-3 drops of 5 per cent tannic acid solution and 2-3 drops of 20 per cent silver nitrate solution may be used it is blackened by ammonia. 

Derivation Interaction of ferric acetate and tannic acid solutions. 

Picric acid solution, Tannic acid solution 1 per cent acetic acid, 1 per cent boric acid, 1 per cent sodium bicarbonate, saturated solution of sodium carbonate. 

To 100 mL of suspect wine, add 5 mL of tannic acid solution. Interpretation Formation of pronounced haze (compared to a control) in treated sample is indicative of unstable protein. 

Adsorption studies Adsorption experiments were carried out by shaking for 24 hours the appropriate ground clay (0.5g) in 50 ml aliquots of a 10 2m buffer solution containing from ca. 4 to 70 mg/1 tannic acid. The suspensions were then centrifuged and the equilibrium concentrations of tannic acid solution were determined from the UV absorbance at 270 nm. It had previously been established that Beer s Law held for this material at this wavelength. 

A recent study by Pospisil (197) showed that tannin may be used as an exogenous antifeedant factor. In this study, Colorado potato beetle larvae refused to eat potato Solarium tuberosum) leaves treated topically with tannic acid solution. In contrast, the larvae of Heliothis spp. exhibited attenuated growth on, but not antifeedant behavior toward a diet containing condensed tannin from Gossypium... 

Figure 9.18 Relative change in vesicle area upon transfer into equiosmolar tannic acid solutions of 10 M (open circles), 10" M (filled circles), 5 x 10 M (open squares), and 10" M (closed squares).

After adding 1ml of 1% (w/v) tannic-acid solution the mixture is heated to 80°C. 

Minerals, particularly Bentonite, ate used to remove proteins that tend to cause haze in white wines. The natural tannin of ted wines usually removes unstable proteins from them. Excess tannin and related phenols can be removed and haze from them prevented by addition of proteins or adsorbents such as polyvinylpyttohdone. Addition of protein such as gelatin along with tannic acid can even be used to remove other proteins from white wines. Egg whites or albumen ate often used to fine ted wines. Casein can be used for either process, because it becomes insoluble in acidic solutions like wines. 

Astringents are designed to dry the skin, denature skin proteins, and tighten or reduce the size of pore openings on the skin surface. These products can have antimicrobial effects and are frequendy buffered to lower the pH of skin. They are perfumed, hydro-alcohoHc solutions of weak acids, such as tannic acid or potassium alum, and various plant extracts, such as bitch leaf extract. The alcohol is not only a suitable solvent but also helps remove excess sebum and soil from the skin. After-shave lotions generally function as astringents. 

Approximately 75 grams of d-amphetamine as a free base was dissolved in 300 ml of isopropanol (solution A). Approximately 200 grams of NF tannic acid was dissolved in 700... 

Determination of tungsten as the trioxide (tannic acid-phenazone method) Discussion. Tungstic acid is incompletely precipitated from solutions of tungstates by tannic acid. If, however, phenazone (2,3-dimethyl-l-phenyl-5-pyrazolone) is added to the cold solution after treatment with excess of tannic acid, precipitation is quantitative. This process effects a separation from aluminium, and also from iron, chromium, manganese, zinc, cobalt, and nickel if a double precipitation is used. 

Stabilization of crude and purified anthocyanin extracts from agai by the addition of tannic acid resulted in a 65% half-life increase of anthocyanins from the crude extract and 610% of the half-life of the purified one. Although tannic acid was considered an efficient copigment,in general all cinnamic acids give unpleasant odors and tastes to solutions. 

Copper(II) oxide and cobalt(II) hydroxide form cements with solutions of many multifunctional organic acids propanetricarboxylic acid, tartaric acid, malic acid, pyruvic acid, mellitic acid, gallic acid, tannic acid and phytic acid (Allen et al., 1984 Prosser et al., 1986). These have been used mainly in cement devices for the sustained release of copper and cobalt (Manston et al., 1985 Mansion Gleed, 1985). Little is known about... 

Tannin solutizer process. In this process, alkyl phenols or isobutyric acid is used in combination with tannic acid and caustic solution. The spent tannin solution is again regenerated by air blown into the solution. 

The bacterial resistance of silk fibroin can be improved by treatment at low pH values in aqueous solutions of metal ions and at high pH values in solutions of metal-amine complexes, using untreated silk or silk pretreated with an aqueous solution of tannic acid (10.183). Suitable metals include Cu, Zn, Ni, Fe and Ag [533]. It is to be expected that treatment with such metal compounds will be subject to restrictions in environmentally sensitive areas. 

For synthesized the gelatin (G)/tannic acid (TA) resin, gelatin powder was purchased from tilker Company-Istanbul, Turkey and tannic acid (TA) purchased from E. Merck. TA powder was dissolved in distilled water at 95-98°C, then solution... 

Furfuryl Alcohol Furfuryl Alcohol Furfuryl Alcohol Isoamyl Alcohol Formaldehyde Solution Gallic Acid Gallic Acid Tannic Acid Tannic Acid Benzene Hexachloride Gas Oil Cracked Copper Nitrate Benzene Hexachloride Acetic Acid Sorbitol... 

Dextrose Solution Glutaraldehyde Solution Glycerine Tannic Acid Glycerine... 

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