Tannin sulphate

Adding other substances which are claimed to act as palliatives for this form of attack. These include sodium sulphate, sodium nitrate and certain tannins. Experience indicates that the maintenance of certain ratios of chemicals is helpful to vulnerable boilers, e.g. sodium sulphate to sodium hydroxide a ratio of 2-50, and sodium nitrate to total alkalinity of 0.4. 

Contact corrosion may be reduced by the presence of natural inhibitors, such as tannins, in the wood, and will be promoted by sulphates and chlorides in it, especially if mineral preserving processes involving these ions have been applied. 

By another method, Reid makes the decoction of galls as above directed, and exposes it freely to the air for ton days, agitating it two or tlirec times eaeh day. By this means much of the tannin is converted into gallic acid. To each quart of the decoction, add three and a half pints of water, nine ounces of sulphate of iron, and the same quantity of gum. The deposit which forms may, after three days, be separated, when tli iak is fit for use. 

Again, one pound of galls is exhausted as first directed, and the tannin of the decoction changed, by exposure, into gallic acid, as in the last instance. The menstruum is then mixed with a saturated solution of logwood, freshly made by boiling a pound and a half of the chips in five quarts of water, till the quantity is reduced to seven pints eighteen ounces of sulphate of iron, and as many of gum, are dissolved in this mixed liquid the whole is allowed to stand for two or three days, and the ink is then, decanted from the sediment. 

In train oil the impurity is not mucus, as in the vegetal oils, but animal gelatin or glue, and, besides this, volatile, stinking matters. Some clarifiers use a solution of tannin for purifying ft, whioh forms with the gelatin insoluble flakes others employ metallic salts, as sulphate of copper or acetate of load, which act in a similar manner, The nauseous odor 1b most easily removed by bleachfng-powder.—Knapp,... 

Ink (melanos) was made from lampblack or soot from burning resins, mixed with gum or glue. Dioscorides mentions that chalcanthum is added. This addition is difficult to understand. Chalcanthum as we have seen was a term including copper sulphate, ferrous sulphate and mixtures of the two. If a solution of nutgalls or other solution of tannin were used, the addition would be comprehensible... 

These components are alcohol, glycerine, sugars, colouring matters, albuminoid and tannin substances, inorganic salts (phosphates, sulphates and chlorides of potassium, sodium, magnesium, calcium and aluminium), non-volatile organic acids (especially tartaric, malic, succinic and lactic, partly free and partly combined as salts), volatile acids (especially acetic) and esters, the latter being the source of the particular perfume or bouquet of the wine. 

Copper sulphate and ammonia. To 2-3 c.c. of the tannin solution are added a little 1% copper sulphate solution and then excess of ammonia, any precipitate being noted. 

Group I includes materials containing tannins derived from pyrocatechol, which give a precipitate with bromine water and a greenish-black coloration with ferric alum. It comprises two sub-groups, with which the precipitate given by copper sulphate (a) redissolves, (6) does not redissolve, in ammonia. 

Sugars may be tested for with Fehling s solution in the tannin solution treated with lead acetate and then with sodium sulphate and subsequently inverted. Since, however, tanning materials generally contain a certain quantity of reducing sugars, addition of glucose cannot always be proved by a mere qualitative test,... 

The precipitate (tannate of iron) is dissolved in dilute sulphuric add and the solution thus obtained extracted with ethyl acetate, the ethereal liquid being then separated from the aqueous solution and evaporated to dryness. The residue (tannic add) is dissolved in water and identified by means of dilute ferric sulphate or ferric alum solution (blackish-blue coloration). If the ink contains logwood, part of this passes with the tannin in such case, to identify the tannin in the aqueous solution of the ethyl acetate extract, distinctly alkaline ammoniacal copper sulphate is added, this giving a pretipitate in presence of tannin. 

In the commoner cases the base is a hydrated metallic oxide (of aluminium, tin, lead, zinc or, less often, chromium, iron, copper, antimony) to which the colouring matter (if acid) is united by true chemical combination tannin lakes are also made (with basic colouring matters). In other lakes the base is an inert substance (barium sulphate, precipitated alumina and silica, chalk, gypsum, kaolin, etc.), on which the colouring matter is fixed by simple mechanical absorption. Lakes of the former kind may be mixed, either fraudulently or for the purpose of attenuating the colour, with inert materials. 

With each of these four groups the procedure is as described later. In the first place, however, the colouring matter is investigated with reference to its tintorial properties by means of dyeing tests on non-mordanted cotton or wool, on wool mordanted with aluminium sulphate and cream of tartar, on wool mordanted with chromium fluoride and cream of tartar, on cotton mordanted with tannin and then with tartar emetic, on cotton mordanted with aluminium acetate and on cotton mordanted with chromium acetate. 

Of the extraneous substances which may be found n artificial organic colouring matters (besides water, especially in pasty materials), some may be derived from the manufacture, such as sodium chloride and sulphate others, such as zinc and ferric chlorides, may form integral parts of certain colours, which are prepared as double salts with these chlorides others may consist of mordants mixed with the colouring matter, such as aluminium, iron, chromium, antimony and copper salts, cream of tartar, tannin, etc. 

The most unstable form of the amorphous variety is colloidal silver, prepared by reduction of an ammoniacal or dilute alcoholic solution of silver nitrate with sodium citrate, sodium potassium tartrate, dextrin, tannin, or formaldehyde, with subsequent addition of ferrous sulphate.13 If forms a chocolate, pale-lilac, blue, or green mass, and dissolves in water to a deep-red solution. The colour depends partly on the mode of... 

Like a number of polyanionic compounds, including sulphated polysaccharides, polyhydroxycarboxylates and various tannins, the flavonoids that we tested seem to interact with the surface glycoprotein gpl20 to prevent binding of the virus to the sCD4 receptor (41). 

Take 5 grains tannin, 16 grains sulphate of quinine, 1 ounce syrup of "nger, and i ounce cinnamon water. Take 1 tea spoonful every hour, in the absence of the fever. 

Sulphuric acid esters of tri- 8-hydroxyethyl-/J-propane tri-carboxylic acid ammonium (ThromboHolzinger), polyethylene sulphate sodium, polyanethol (liquoid), polyvinyl alcohol (elvanol), yeast nucleic acid, lignin, saponin, tannin, oromucoid, proteins... 

The tannin from gall-nuts is used in making writing inks. Ordinary inks were formerly made from an extract of galls to which a gum, ferrous sulphate, a trace of sulphuric acid, and a blue dye were added. The acid prevents the oxidation of the ferrous sulphate and thus renders the ink stable the dye gives a color to the solution so that the writing made with it can be seen. When the ink is placed on paper the alumina in the latter neutralizes the acid, and the ferric salt formed as the result of action of the air, reacts with the tannin and a black compound is produced. 

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