Direct colorimetric and volumetric determination of calcium with new reagent

The anthor found that azocal-A reacts only with calcium, and devised a direct colorimetric, and a direct titration method for calcium determination using azocal-A as an indicator, and obtained a satisfactory result. Accuracy : detectable amount in NaOH……0.28 γ, of Ca ; detectable amount in NH(4)OH……2 γ, of Ca. Sensibility……1 : 125,000 & 1 : 17,500 respectively. Interfering substances : Fe, U, Ni, Co, Hg, Ag, citrate, tartarate, oxalate, large amount of NH(4) salts, Sr, Mg. Not interfering subst. : Ba, F, acetate and silicate. Reagents : Saturated soln. of azocal-A in weak NaOH soln.. Spot test procedure : Place a drop of the acid or neutral test soln. upon white spot plate, add 1 drop of azocal-A soln., and mix them. If a yellow color appears, calcium is present. Colorimetric method: Transfer water sample containg not more than 0.05 mg of calcium, and not more than 5 mg of Fe, Mn, Mg, etc. to a 20 cc colorimetric tube, add 0.5-1 cc of azocal-A soln. and 0.5 cc of 6N-NaOH soln.. Allow it to stand for 10 minutes. Then compare the resulted yellow color with standard Ca soln. prepared similarly and simultaneously. Volumetric method : Amount determinable : 0.1 g of calcium. Transfer 40 cc of sample containg 5-100 mg to a 100 cc Erlenmeyer's flask, add 0.5 cc of 6N-HCl, add azocal-A to the amount of pink color as caused by methyl orange in acid soln.. Make alkaline with 1 cc of 6N-NaOH. Add 10 cc alcohol to every 40 cc of the sample solution. Then its color turns to yellow. Titrate with 0.1 N oxalate soln.. 1.0 cc of 0.1 N oxalate soln. is equivalent to 2.0 mg of Ca. Absorption band of the acid soln. at 4900 A, alkaline soln. at 5000 A, Ca-compound at 4300 A. The azocal-A is o-carboxy-benzol-azo-2-naphtol 3, 6-disulfonic acid prepared from anthranilic acid and R-salt

STUDIES ON THE VITRIOL SPRINGS. (6)

a) Colorimetoric determnation of the minute amount of antimony and antimony contend of Yanahara Hot Spring. To 5cc of sample soln., not containing the second family other than antimony. add 0.2 cc of 10% polyvinyl alcohol aqueous solution. Adjast HCI eoncentration to approximately I. N. Add I cc of hydrogene sulfide solution and sbake. Then measure the reruting yellow or orange color by photometer. Antimony content of Yanahara Hot Spring was 0.1±0.03 g per liter by the above mentioned method. b) Quantitative determination of the free mineral acid. Precipitate iron and aluminium as complex fluorine salts and change the sulfate ion into alkali sulfate, so that it can not liberate free acid. Then titrate with alkali using phenol red as an indicator. c) Iron and coprer in thermal waters and minerals of Yanahara Hot Spring. Ferous ion content of Yanahara Hot Spring (60℃) was 14.6g per liter and its copper content was 0.44g per liter. both being the highest record in Japan. A green and a bluish green minerals ware found, crystalyzed near the Hot Sprig. The latter was apisanite (Cu(0.25) Fe(0.75) S0(4・8.8) H(2)O) and the former proved to be a pure melanterite (Fe S0(4).7H(2)O). d) A modified method to detect sulfides of the second family. Using zinc-amalgam the author succeeded to avoid the liberation of sulphur and to detect the yellowish or orange colored sulfides, such as ausenic, antimony or tin sulfide. e) Paper chromatography applied to the analysis of heavy metals in vitriol waters. 4 kinds of vitiol waters were investigated. Paper chromatography proved to be excellent in detecting the metals of the second family, such as tin, antimony, and ansenic

COPPER AND ZINC CONTENT OF BLOOD AFTER INTRAVENOUS INJECTION OF DITHIZONE OR OXIN IN RABBIT

Okamoto found that not only alloxan but also dithizone or oxin can produce diabetes in the test animals and proposed a zinc theory of diabetes. As dithizone and oxin react not only with zinc but also with many other metals, such as copper, nickel, cobalt, bismuth, silver etc, the author investigated the copper and zinc content of blood after intravenous administration of dithizone (100 mg per kg of bodyweight) or oxin (50 mg per kg of bodyweight) to rabbit by chromatographic method devised by the author. Both zinc and copper in blood decreased soon after the injection of the above-mentioned reagents and recovered only slowly after 24 - 48 hours

BALNEOLOGICAL STUDIES USING RADIOACTIVE ISOTOPES (3)

By using labelled sodium sulfate or calcium sulfate (sulfate containing S(35)) the transition of sulfate ion into the body across the skin was investigated soon after taking a bath in sodium sulfate or calcium sulfate solution under varing conditions. Mice were used for experiments. The percutaneous absorption of sulfate ion proved to decrease gradually in the course of serial baths in sodium sulfate solntion and was accelerated by making a fresh burn on the skin of the bathed animals, but it showed a tendency to decrease as the wound became more and more healed. The application of basic dye to the skin (e.g. 1% methylenblue or 1% fuchsin solution) increased the transition of sulfate ion into the test animal. Little difference was proved between the bath in sodium sulfate and calcium sulfate solution with respect to the penetration of sulfate ion. Passage of sulfate ion from the bath water through the skin was a little promoted by the use of sodium sulfate solution than by the use of calcium sulfate solution

CHROMATOGRAPHIC ANALYSIS OF METALS BY ORGANIC REAGENTS (Ist Report)

The principle of this method is to combine the metals with organic reagents, then extract them with non-polar solvents, and determine them by making chromatograph with adequate adsorbents. Dithizone is used to determine Hg, Cd, Bi, Ag, Cu, Zn, Ni, Co, Tl, Pb, Pd and its isotopes, Pt group, Au, etc. Diphenylcarbazone is applicable to determine Hg, Cu, Zn, Ni, etc. Xanthate is useful to determine Mo, Cu, Ni, Co, etc. α-orβ- Nitrosoβ- orα-naphthol is used to determine Fe, Co, earth acids etc. Diethyldithiocarbamate is used to determine Mo, Cu, Ni, Co, Fe, etc. Oxine series are useful to determine Cu, Ni, Fe, V, rare earth etc. α-indolcarbonic acid is applied to determine Fe, Co, rare earth etc. Acethyl acetone is used to determine Th, Fe, etc. Some other organic reagents were used moreover. There are some elements of which necessary condition for quantitative determination is still not decided or the order of adsorption is indefmite. As adsorbents alkaline, neutral or acid alumina, diatom earth and aluminate, magnesium carbonate, calcium carbonate, urea formaline resin, heulandite, mordenite, desmine, chabazite etc· were used. With this method the author tryed severd determinations on rocks, minerals, mineral springs, organisms etc. The contento; of Cu, Zn, Ni and Co in rocks were 0.007, 0.008, 0.002 and 0.004% respectively. Cobalt content proved to be more than that of nickel. The mercury content of rocks was proved to be 10 times more to Clarke number, bismuth and cadmium content as same as or less than Clarke number. Silver in plants, soil and mineral waters, platinum in serpentine; mercury, cadmium, bismuth etc in mineral waters, trace heavy metals in organism, etc were determined. Radium B and Thorium B in hot spring waters were used as tracer. As organic solvents methyl-, ethyl-, butyl-, amy1-, octyl alcohol, dioxan, benzol, toluene, xylol, petroleum ether, ether, ethylacetate, chloloform, carbon tetrachloride, carbon disulfide etc were applied

FLOCCULATION VALUE OF MINERAL WATERS.

Flocculation value of 24 mineral waters was measured with colloidal solution of iron hydroxide. There exists a negative correlation (r=-0.72, Fo=(r(2)(N-2))/(1-r(2)) =21.6 >F=8.10 n1=1 n2=20 α=0.01) between the logarithms of sulfate ion concentration of the mineral waters and their Flocculation value

COLORIMETRIC DETERMINATION OF MAGNESIUM IN NATURAL WATERS

Using dye reagents of Magneson Series, the author Succeeded to determine minute amount of magnesium in natural waters (0.0001-0.01g periiter) Colorimetrically. And with Complex salts of Cobalt and copper as Substitutive Standard color series a Simple, rapid and exact method Suitable for field work was devised