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Volume 33, Issue 12
Displaying 1-24 of 24 articles from this issue
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Toshio KUBOTA, Toshio UEDA, Tadao OKUTANI1984 Volume 33 Issue 12 Pages 633-637
Published: December 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA graphite furnace atomic absorption method for simple and rapid determination of phosphorus, using a zirconium treated graphite tube has been studied. Zirconium treatment of a graphite tube was as follows : A graphite tube was soaked in a 10 % zirconium solution in a test tube under a reduced pressure for 10 min. After drying, it was heated slowly up to 500 °C for 40 s, up to 1500 °C for 60 s and then at 2200 °C for 6 s in a graphite furnace. The analytical procedure was as follows : A 20 μl of 1 % zirconium solution was injected in the zirconium treated graphite tube, and was dried. Then, a 20 μl of sample solution was injected in it, and the graphite furnace was operated : drying at 150 °C for 60 s, ashing at 1620 °C for 60 s, atomization at 2140 °C for 6 s, and argon flow rate of 2 l/min. Back ground correction was not used. Injection of zirconium solution in the graphite furnace before each atomization cycle, resulted in an increase in about 10 times as much phosphorus peak height as that of no injection of zirconium soltion. Employing untreated graphite tube, the peak height of phosphorus was gradually increased on repeated runs. On the other hand, that of phosphorus in the proposed analytical procedure resulted in good reproducibility. A calibration curve obtained shows linear up to 70 ng-P. The detection limit is 3 ng (0.15 ppm using a 20μl volume), and relative standard deviation for 20 ng-P is 56 % in 10 runs. The proposed method was applied to the analysis of NBS standard reference material (SRM-1575) and plant samples with satisfactory results.View full abstractDownload PDF (626K) -
Hiromasa KATO, Mitsumasa ONO, Shinichi KUWATA1984 Volume 33 Issue 12 Pages 638-642
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSHitherto the commercial Karl Fischer coulometric reagents contained much pyridine as a component, and the odor of pyridine was unpleasant for the operators. New bases instead of pyridine were searched in order to solve this problem. Karl Fischer coulometric reagents were prepared with various odorless bases. Using a commercial coulometric moisture titrator, electrolytic current vs. time curves for those prepared reagents were obtained. From these experiments, it is found that the mixture of an aminopyridine compound and a dipyridyl compound was most suitable for Karl Fischer coulometric reagent which had low blank current and good accuracy for determination of moisture. Using a new Karl Fischer coulometric reagent prepared with those bases, the moisture in various samples-hydrocarbons, alcohols, ethers, esters, and other chemical products-was determined. Good agreement was found between the results with the new reagent and those with the conventional reagent contained pyridine.View full abstractDownload PDF (839K) -
Fujio MORISHITA, Yoshiaki HARA, Tsugio KOJIMA1984 Volume 33 Issue 12 Pages 642-647
Published: December 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSL-Lactate was determined by flow injection analysis with a narrow-bore glass capillary open tubular reactor, on the inner wall of which silica whisker was formed and lactate dehydrogenase was immobilized by covalent attachment. The sample solution (5 to 10 μl) was injected into a carrier stream (pH 6.5 to 10.5) containing 2 mM NAD. L-Lactate and NAD were enzymatically converted to pyruvate and NADH, respectively. The last was monitored with a fluorometric detector (excitation 340 nm, emission 470 nm). The flow rate of the carrier solution, the reactor length and the pressure drop across the reactor required to achieve a given pair of the sampling rate and the reaction time were calculated and discussed for the various inside diameters of the reactor, in the case where the extra-reactor spreading of a sample band cannot be neglected. The extent of dilution of the sample band with the cairrer solution was also calculated as a function of the reaction time. The moderately large extra-reactor volume (about 40 μl) resulted in the choice of 0.3 mm I.D. reactor due to not too high pressure drop and not too large dilution for high sampling rate and long reaction time. The relative standard deviation of peak height, measured by repeated injections of the sample solution containing higher than 0.01 mM L-lactate at 30-s intervals, was about 2 % for 20-s residence time in a 0.3 mm I. D. x 300 cm reactor.View full abstractDownload PDF (858K) -
Kazuko KIHARA, Souji ROKUSHIKA, Hiroyuki HATANO1984 Volume 33 Issue 12 Pages 647-652
Published: December 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA simplified saponification and derivatization procedure was proposed for microanalysis of fatty acids in fat and oil. The procedure involved miniaturized one-pot reaction, in which fat or oil (0.011 mg) was first hydrolyzed with 0.1 M methanolic KOH (0.2 ml) in a sealed vial. After heating at 90 °C for 10 min, the solvent was removed, and the resulting fatty acid potassium salts were reacted with phenacyl, p-bromophenacyl or 2-naphthacyl bromide in the presence of 18-crown-6 in 1 ml of chloroform. Then obtained UV-labelled esters were analyzed by liquid chromatography on an ODS column. The esters were stable in the reaction mixture for 3 months in the dark. The chromatographic response was linear to the concentration of fatty acid from 5μM to 5 mM. The relative sensitivity of phenacyl, p-bromophenacyl, and 2-naphthacyl esters was approximately 1 : 2 : 3 when monitored at 254 nm. Although the latter two esters were more sensitive, some by-product peaks overlapped the analyte ester peaks for lower fatty acids (≤C10). Phenacyl bromide, on the other hand, produced less by-products, and the reagent could be used to the analysis of those esters down to C7 acid. Commercial butter fat constituents were analyzed by the proposed simplified micro-analytical procedure, and the result was in good agreement with those obtained by the conventional method.View full abstractDownload PDF (810K) -
Takeshi YAMANE, Yasuhiko NOZAWA1984 Volume 33 Issue 12 Pages 652-656
Published: December 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe manganese-catalyzed oxidation of protocatechuic acid by hydrogen peroxide in sodium carbonate media has been successfully used in a flow injection system for the catalytic determination of trace manganese. The sample solution (75 μl) injected into carrier stream meets the flowing reagent solution containing protocatechuic acid, hydrogen peroxide, and sodium carbonate at confluence point and the catalyzed oxidation proceeds while the sample zone moves forward through the reaction coil to the flow-through cell. The increase in absorbance was monitored at 480 nm. The signal recorded is a peak with a sharp initial rise. A linear relationship between peak height and manganese concentration was obtained in the range 040 ng/ml, while the further increase in the manganese concentration resulted in a slight negative deviation from the linear dependence. The proposed method has a limit of detection of 1 ng/ml and permits ca. 60 determinations per hour. A relative standard deviation of 2.0 % (n=15) was observed for the sample containing 10 ng/ml manganese. Cobalt interfered seriously owing to its catalytic action even at the same concentration levels as manganese. Iron(III) and chromium(III) interfered when present in concentrations above 20 and 10-fold excess, respectively. Many of the other ions examined, however, had no effect on the manganese determination when present in 200 to 500-fold excess.View full abstractDownload PDF (613K) -
III. Determination of soap using dichlorofluorescein as indicatorAkira HASEGAWA, Makoto YAMANAKA1984 Volume 33 Issue 12 Pages 657-662
Published: December 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSExperimental conditions were studied for the determination of C6C18 fatty acids by two-phase automatic photometric titration. The salts of fatty acids were back-titrated with standard sodium dodecylsulfate after addition of excess Benzethonium chloride in water-chloroform medium. An automated titrator equipped with porous PTFE (Teflon) membrane separator (previous publications, literatures 1 and 2) was used. Using the method proposed, determination of long-chain fatty acids was satisfactory, while short-chain acids generally gave lower end point (lower recoveries) due to their incomplete extraction. Addition of 14 % 1-propanol into the aqueous solution was effective to improve the recovery of short-chain fatty acids. Among indicators tested (Bromocresol Green and several fluorescein derivatives), 2', 7'-dichlorofluorescein proved to be satisfactory in applicability to wider range of fatty acids and in sharp end-point indicator. Under the recommended conditions, recoveries were 0, 26.3, and 85.4 % for C6, C8, C10 acids, respectively;those of the longer-chain fatty acids were quantitative. However, a soap containing a mixture of short-chain fatty acids was successfully analyzed by using the modified molecular weights which were obtained from the experimentally determined recovery of each C6C10 acid. Typically titration time required was 1520 min per sample, and the relative standard deviation of determination was about 0.3 %.View full abstractDownload PDF (741K) -
Shoichiro TAGAMI1984 Volume 33 Issue 12 Pages 663-666
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThis paper describes a potentiometric method using the gas-permeable membrane electrode for drug ana-ysis. Trimethadione decomposes into carboxylic acid and methyl amine and Na2CO3 on heating with 1 M NaOH. After acidification, the CO2 was determined with a CO2 electrode. The procedure was as follows : A mixture of 375.85 mg of trimethadione and 50 ml of 1 M NaOH was boiled for 20 min. The solution was cooled, neutralized with HCl solution to pH 8.5 and diluted to 250 ml. A 50 ml portion of the sample solution was acidified with 5 ml of 0.1 M citrate buffer (pH 4.5). The CO2 electrode with 0.01 M NaHCO3 internal filling solution was placed in the solution and the potential was measured with a pH meter at 20 °C. When the potential versus the logarithm of drug concentration was plotted, linear calibration curve was obtained in the drug concentration range of 1 × 10-31 × 10-2 M. If nitrogen was used to expel CO2 from air, the linear calibration curve was obtained in the concentration range of 3 × 10-41 × 10-2 M. The sample concentration was determined from the calibration curve by using Na2CO3 standard solutions. The amount of the pure powder was estimated with 99.74 % and the standard deviation was ±0.13. In the case of tablets, trimethadione was extracted with acetone, and after evaporated of acetone, the residue was determined with the above method. The CO2electrode method had several advantages. It had high sensitivity and precision. Sodium carbonate could be used as the standard substance and the CO2 measurement was easy and rapid.View full abstractDownload PDF (507K) -
Availability of excitation derivative spectrumYoshiaki YOSHITAKE, Shiro GOHDA, Hideo YAMAZAKI, Kiyotoshi MORISHIGE, ...1984 Volume 33 Issue 12 Pages 667-679
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSAnalysis of chlorophylls and pheophytins is indispensable for the estimation of physiological biomass and/or environmental pollution. However, there are no remarkable difference in spectral properties between chlorophylls and degradation products. Excitation and emission maximal wavelength of chlorophylls and pheophytins were as follows; chlorophyll a (430/666 nm), chlorophyll b (457/650 nm), pheophytin a (410/670 nm), pheophytin b (435/655 nm). It indicates that coexistence of a large amount of degradation products causes a large error on the determination of chlorophylls and pheophytins. Therefore, derivative fluorometric method was utilized for the analysis of chlorophylls and pheophytins, because this method is essentially profitable to analyze the spectra which are largely overlap. In particular, it was realized that excitation derivative spectrum method (Em.=666 nm; excitation wavelength was driven from 380 to 500 nm) was effective for the determination of chlorophylls in environmental samples that coexist many degradation products. Further, the selectivity of this technique can be increased by excitation and emission derivative spectrum methods combined with paper chromatography. The relative standard deviation of the measurements was less than 4.0 % (9 determinations) for chlorophylls a, b and pheophytins a, b, even when amounts of the other three pigments were 20-fold than that of the desired pigment. By using this method, chlorophylls a, b and pheophytins a, b in environmental samples with ppb levels could be determined.View full abstractDownload PDF (850K) -
Takeshi NAGANUMA1984 Volume 33 Issue 12 Pages 672-675
Published: December 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSMercury in sea water is determined by a fluorometric method with Rhodamine B, after preconcentration by means of coprecipitation with p-dimethylaminobenzyly-denerhodanine (PDBR) and generation of mercury vapor with stannous chloride. Ten milliliters of 0.05 % PDBR acetone solution is added to 11 of sample solution containing 0.11.0 μg of mercury, then the solution is adjusted to pH 7.0 with aqueous ammonia and hydrochloric acid. After standing over night, the precipitate is collected by a centrifuge method, dissolved in 3 ml of aqua regia, and transferred to a reaction vessel, followed by dilution to about 50 ml with water. Into the reaction vessel, 2 ml of 1 M stannous chloride solution is added and air is bubbled for 8 min. Mercury vapor generated from the sample is trapped in a potassium permanganate-sulfuric acid solution. After 1.5 ml of a 0.5 % hydroxylamine hydrochloride solution is added to reduce the excess of permanganate ion, 1 ml of 0.02 M hydrobromic acid and 0.5 ml of a 0.3 % Rhodamine B solution are added and the solution is shaken with 5 ml of toluene. The mercury extracted in toluene is determined by fluorometry at 560 nm (excitation) and 580 nm (emission). The recoveries of mercury are almost quantitative and the relative standard deviation is about 3 % in five determinations of mercury at 0.3 ppb level.View full abstractDownload PDF (504K) -
Takeo KATAMI, Tomokuni HAYAKAWA, Masamichi FURUKAWA, Shozo SHIBATA1984 Volume 33 Issue 12 Pages 676-678
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA sensitive and selective method for the spectrophotometric determination of palladium(II) with2-(2-benzothiazolylazo)-5-dimethylaminobenzoic acid (BTAMB) has been studied. BTAMB reacts with palladium(II) in aqueous acetone solution (35 % acetone by volume) to form a blue complex with an absorption peak at 695 nm with ε =4.96 × 104 1 mol-1 cm-1. The complex is stable for at least 6 h and its stoichiometric ratio of the complex is 1: 1 (Pd : BTAMB). The calibration graph is linear over the concentration range 035μg of palladium(II) per 20 ml of the aqueous acetone solution in a range of pH 2.06.0. The relative standard deviation for 10 determinations at 30.0 μg palladium(II) level is 0.58 %. Common anions and cations do not interfere. The interferences due to Ag(I), Co(II), Cu(II), Ni(II), Os(VIII), Pt(IV), and V(V) can be masked by sodium citrate, and copper(II) by trisodium nitrilotriacetate. The recommended procedure is as follows : Take 5 ml of sample solution containing up to 35 μg of palladium(II) into a 50 ml beaker, add 1 ml of 1 % sodium citrate and 3 ml of 0.2 M potassium hydrogen phthalate buffer (pH 2.5), and adjust the pH to 2.5 with 10 % sodium hydroxide solution. Transfer the solution into a 20 ml glass stoppered test-tube. Add 0.7 ml of 0.05 % BTAMB and 7 ml of acetone. Dilute it to 20 ml with distilled water. After standing for about 10 min, measure the absorbance at 695 nm against the reagent blank. By this procedure, palladium(II) content in catalyst for the clarifier of car exhaust gas was determined.View full abstractDownload PDF (464K) -
Masakazu DEGUCHI, Noritsugu EBISUYA, Kiyotoshi MORISHIGE1984 Volume 33 Issue 12 Pages 678-681
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIndium reacts quantitatively with 2-hydroxy-5 sulfoaniline-N-salicylidene (HSS) to form a yellow complex at pH 7.07.2.The complex in an aqueous solution has an absorption maximum at 415 nm and the absorbance is stable for at least 24 h. The analytical procedure is as follows : One ml of a sample solution containing 150μg of indium (0.1 M hydrochloric acid solution) was diluted to about 15 ml with water. Five ml of 30 w/v % sodium acetate solution, an adequate amount of 0.1 M sodium hydroxide solution and 2 ml of 0.2 w/v % HSS solution in DMF were added. Then the mixture was diluted to 25 ml with water (the final pH : 7.1± 0.1). After 20 min, the absorbance was measured at 415 nm against the reagent blank. Beer's law was obeyed over the range of 150μg/25 ml of indium. The relative standard deviation (n = 5) on the absorbance for 30μg of indium was 0.5 %. The molar absorptivity was 3.16 × 104 1 mo1-1 cm-1. The molar ratio of indium to HSS in the complex was estimated to be 1 : 2 by the continuous variation method. Aluminum(III), gallium(III), scandium (III ), copper (II), and iron (III) interfered seriously. However, idium could be separated by extraction procedure with isopropylether from these interfering ions. By this method, trace amounts of indium mixed with high purity zinc could be successfully determined.View full abstractDownload PDF (618K) -
Motoko TAKEDA, Masako MAEDA, Akio TSUJI1984 Volume 33 Issue 12 Pages 681-683
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe fluorescence high performance liquid chromatography of uronic acids is developed. Various uronic acids, such as glucuronic acid, galacturonic acid, and mannuronic acid, were mixed with 100 μl of 0.75 % trichloroacetic acid-ethanol solution and 100 μl of 1.0 % dansylhydrazine-ethanol solution. The mixture was incubated for 45 min at 40°C and then cooled to room temperature. An aliquot of the resulting solution was injected into a Finepak SIL-NH2 column of the chromatograph. Good separation of uronic acids was obtained within about fifteen minutes by elution system using acetonitrile/acetate buffer (pH 5.6) (90/20 : v/v). The fluorescence of the eluate was monitored at 530 nm, when the excitation was made at 350 nm. Linearity of the fluorescence intensity with the amounts of uronic acids was obtained between 0.1 and 20 nmol. Detection limit was about 50 pmol of uronic acids. The proposed method is applicable to detection of various acids in glycosaminoglycans and other biological substances.View full abstractDownload PDF (321K) -
Takashi KORENAGA, Kimiko OKADA1984 Volume 33 Issue 12 Pages 683-686
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA flow injection analysis system was devised for the continuous determination of total phosphorus. Into a steady stream of persulfate solution at a rate of 1.2 ml/min, a 310 of sample was injected and digested in the stream by heating to 120 °C. The sample was then merged with a stream of acidic molybdate reagent at a rate of 0.2 ml/min and heated at 75°C to produce molybdophosphate blue. The absorbance of the blue complex was measured at 880 nm. The determination range was 0.0110 mg P/1. The sampling rate was 10 samples per hour. The precision of the method was 0.7 % as standard deviation. Total phosphorus in several waste water samples was analyzed by both the flow injection method proposed here and the conventional manual method, and good agreement on the results was observed between the two. The automated method would be applicable to continuous monitoring of total phosphorus in industrial waste waters etc.View full abstractDownload PDF (520K) -
Hiroshi SHIMIZU, Takashi ONOUE, Takehiro MURAYAMA1984 Volume 33 Issue 12 Pages T123-T126
Published: December 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA high sensitive analytical method by graphite furnace Zeeman atomic absorption spectrometry with MIBK extraction was developed for the determination of ppb level of gold in ores. The outline of the proposed method is as follows; 0.15g of rocks or ores (07μg as gold) are decomposed with 2050 ml aqua regia and concentrated to about 10 ml. After the addition of 20 ml of (1+1) HCl, the sample solution is heated for a few minutes and filtered. The filtrate is concentrated to 10 ml and dilute to 30 ml (2 M HCl), and shaken with 10 ml of MIBK. If the residue still contains gold, it is treated with HF. However, this procedure can be omitted for the sample pulverized to less than 100 mesh. The MIBK solvent phase is washed with 0.5 M HCl solution for removing iron interference. 1030μl of MIBK extract is pipetted into a graphite furnace. Atomization program of the furnace is; Drying : at 100°C ramp mode for 30 s, Ashing : at 400°C for 20 s, Atomizing : at 2700°C for 7 s. The content of gold is obtained from the absorbance at 242.8 nm with the calibration curve. The detection limit of the proposed method was 1 ppb. The interfering elements were ten thousand fold of tin, mercury, and osmium. The accuracy of the proposed method was confirmed with geological reference samples.View full abstractDownload PDF (536K) -
Kazuo SOMENO, Masahiro KAISE1984 Volume 33 Issue 12 Pages T127-T132
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe ESR spectrum data bank system was developed for applications in analytical chemistry. The system was comprised of three interrelated files called ESREDIT, LOOKESR, and SIMUL, and had the function of a part of Kagiken spectrum data bank system (SDBS). ESREDIT was constructed of the data base management programs. LOOKESR was for the data base search system, and SIMUL consisted of simulation programs for ESR spectra of free radicals and metal complexes in solution, polycrystalline states, and viscous liquid states. The each record in the data base used for the system contained intensities of an ESR spectrum (digital values) and its parameter (substance name, ESR parameter values, measurement conditions, comment, and literatures cited). LOOKESR had additional capabilities of data base searching by precurser substances. Examples of applications of LOOKESR, and SIMUL were given for analysis of a radical structure produced from oxidation reaction of aniline and in precise determination of ESR parameters of copper complexes in a polycrystalline state.View full abstractDownload PDF (615K) -
Haruo HONMA, Hisako YANASHIMA, Keiko SUZUKI, Mutsuko YOSHIDA1984 Volume 33 Issue 12 Pages T133-T137
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA new type of reduction tube was developed to determine organic carbon, hydrogen, and nitrogen more accurately and efficiently. The conventional reduction tubes, both the small and large types, caused some problems in routine analysis. For example, the small reduction tube gave satisfactory blank values and sensitivities, but its capacity was limited and it was necessary to renew the filling frequently. In the large reduction tube, the combustion gases tended to pass through without reacting because the reduced copper contracted in volume more than that of the small tube. The new reduction tube was S-shaped and had the same diameter as the small tube. The volume was about 3 times that of the small tube and a half that of the large tube. For these three reduction tubes, stabilities of blank values and sensitivities, and other characteristics were compared. The blank values of S-type reduction tube were more stable and the time for stabilizing was shorter than those of the others. All of the three tubes gave satisfactory sensitivities without difference in precision but the large tube has a greater sensitivity variation with time. The numbers of efficient operation/1 g Cu were 2.47 for the S-type, 2.36 for the small type, and 2.26 for the large type. The sensitivities of seven standard samples with the S-type tube were all in allowable ranges and the results of the total elemental analyses were good with respect to accuracy and precision, showing that the new tube was superior to the conventional tubes.View full abstractDownload PDF (708K) -
Akio ICHIMURA, Yoshikane MORIMOTO, Hideki KITAMURA, Toyokichi KITAGAWA1984 Volume 33 Issue 12 Pages E503-E510
Published: December 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe metal-1-pyrrolidinecarbodithioate M(pcd)m, M=Mn(III), Fe(III), Co(III), Ni(II), Cu(II), Zn(II), In(III), Sb(III), Tl(I), Pb(II), and Bi(III), extracted from tartrate into isobutyl methyl ketone (IBMK, 4-methyl-2-pentanone), gives reduction and oxidation waves. The oxidation process is the anodic exchange reactions of the type (2/m)M(pcd)m + Hg_??_Hg(pcd)2 + (2/m)Mm+ + 2e-that can be studied electrochemically with Nernstian treatments. The formation constants of M(pcd)m in IBMK were calculated from the half-wave potentials of the anodic exchange reactions at a dropping mercury electrode. The adsorption pre-wave was observed in the oxidation wave for Zn(pcd)2 and the surface excess was calculated.View full abstractDownload PDF (722K) -
Hidekazu DOE, Akiko MATSUDA, Toyokichi KITAGAWA1984 Volume 33 Issue 12 Pages E511-E515
Published: December 05, 1984
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSThe stability constants of M(II)Cl2 (M(II) = Ca, Sr, Ba) in methanol have been determined by Cl- ion measurements with Ag-AgCl electrodes. All measurements were made at 25.0 ± 0.1 °C and at an ionicstrength of about 0.05 M, adjusted with sodium and the respective metal perchlorates. Since both of the stepwise stability constants, K1 for monochloride and K2 for dichloride, were relatively small, the K2 values could not be determined with this measurements at a low ionic strength whereas the K1 values were obtained with somewhat larger errors. It is interesting that the order of magnitude in K1 is Sr > Ba ≅ Ca in contrast with the order for ionic association constants of their perchlorates, Ba > Sr > Ca, obtained from our conductometric measurements.View full abstractDownload PDF (426K) -
Kazuo HIRAYAMA, Nobuyuki UNOHARA1984 Volume 33 Issue 12 Pages E517-E524
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA highly sensitive catalytic method for determining ultratrace amounts of manganese(II) has been described. The method is based on the catalytic oxidation of N, N-diethylaniline by potassium periodate in weakly acidic media. The catalyzed reaction was followed spectrophotometrically at 470 nm by the fixed time method. By adjustment of variables affecting the reaction, manganese(II) in the concentration range of 10 - 80 pg ml-1 could be determined. Most of coexisting ions did not interfere with the determination, while interfering ions, copper(II), vanadium(V) and chromium(III), were allowed to coexist up to 500 times the amounts of manganese(II). The relative standard deviation at 40 pg ml-1 of manganese(II) was 3.0% (n=6). The accuracy of the method was confirmed by standard materials. The present method was successfully applied to the determination of trace manganese(II) in natural waters.View full abstractDownload PDF (585K) -
S.K.SRIVASTAVA, C.K.JAIN1984 Volume 33 Issue 12 Pages E525-E530
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA heterogeneous membrane electrode fabricated with hydrous thorium oxide gel embedded in polystyrene matrix as the sensor material, has been used for the estimation of strontium ions. The electrode responds to strontium ion in a nearly Nernstian manner over the concentration range 10-1 to 10-4 M. It can be used in the pH range 2.5 to 5.5 as well as in partially non-aqueous system. The membrane electrode shows good selectivity to strotium ions. A membrane treated with cationic surfactant not only becomes immune to detergent interference, but also exhibits a larger validity range. It has also been used as an indicator electrode in potentiometric titrations involving strontium ions.View full abstractDownload PDF (428K) -
Analytical application of ο, ο'-dialkyldithiophosphate IIKenjiro HAYASHI, Yoshiaki SASAKI, Shigehiro INOMATA, Kenji KAWAHARA1984 Volume 33 Issue 12 Pages E531-E534
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSBismuth(III) was extracted quantitatively into hexane from the aqueous phase containing 1 mmol dm-3 ο, ο'-diethyldithiophosphate(dtp-) at pH 0-4, and determined at 325 nm(ε=1.51×104mol-1dm3cm-1) or 395 nm(ε=4.09× 103mol-1dm3cm-1). The species extracted was [Bi(dtp)3] and the extraction constant for this complex was determined as 2.0×1018(mol dm-3)-3.View full abstractDownload PDF (300K) -
Koreharu OGATA, Shinobu SOMA, Ichiro KOSHIISHI, Shinzo TANABE, Toshio ...1984 Volume 33 Issue 12 Pages E535-E538
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA rapid method for the determination of silicate in phosphate rich samples was established by flow injection analysis (FIA) coupled with a suppression column and solvent extraction system. The sampling rate was about 40 samples/h and the detection limit was 0.01 μg/ml (500 pg as Si).View full abstractDownload PDF (337K) -
Satoshi KUSAKABE, Yoshihiro HIROTA1984 Volume 33 Issue 12 Pages E539-E542
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSAlkali metal ions in aqueous 0.1 mol dm-3 sodium chloride solutions were extracted as 2-thenoyltrifluoroacetonates into methyl isobutyl ketone, nitrobenzene, and chloroform at 298 K. On the basis of the extraction curves, the extracted species was considered whether it was a metal chelate or an ion-pair.View full abstractDownload PDF (396K) -
Hiroki YONEZAWA, Kenji KOBAYASHI, Atsuo IIDA, Yohichi GOHSHI1984 Volume 33 Issue 12 Pages E543-E545
Published: December 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSMinimum detection limit obtainable for elements in thin samples by synchrotron radiation X-ray fluorescence analysis was studied. The thin samples containing various kinds of elements were prepared from filter paper and excited by monochromatic X-rays of 10, 15 and 20 keV. The minimum detection limits with energy dispersive spectrometer were 0.14 to 0.35 ppm for 24Cr - 39Y and 0.58 to 0.81 ppm for 63Eu - 79Au.View full abstractDownload PDF (290K)
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