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

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

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

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news article about sovereignty in hawaii approved by many Hawaians in the community along with other statitics on the pol

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

Observations of Collision-Induced Dipole Transitions Associated with High-Lying States of Calcium in Rare Gases

More than 20 collision-induced dipole (CID) transitions have been observed in the absorption spectrum of calcium below 2400 A in the presence of xenon or krypton. Some have also been observed in the presence of argon, neon or helium. The measured shifts and the effective oscillator strengths show a close correlation with the s-wave amplitude for the electron scattering by a rare-gas atom. This correlation leads us to the conclusion that the low-energy-electron-scattering process is responsible for the appearance of the CID transitions