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Volume 40, Issue 10
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Toshitaka HORI, Sadayuki HIMENO1991 Volume 40 Issue 10 Pages 507-524
Published: 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSSeveral, new species of heteropolymolybdate complexes are formed in aqueous solutions containing water-miscible organic solvents. They include β-[PMo12O40]3-, anticipated by analogy with β-[SiMo12O40]4- or β-[GeMo12O40]4-; a family of molybdosulfates, [S2Mo18O62]4-, [SMo12O40]2- and [S2Mo5O23]4- where tetrahedral SO42- serves as a hetero-ion as PO43- does in molybdophosphates; a family of molybdovanadates, [VMo12O40]3- and [Hx-1V(VxMo12-x)O40]3- (x = 1, 2 and 3) containing vanadium as both the hetero-atom and the addenda-atom; a molybdopyrophosphate unambiguously identified as [P2Mo18O61]4- containing P2O74- as a hetero-ion; and a group of molyb-dophosphonates, [(HP)5Mo6O33]10-, [(HP)4Mo8O36]8- and [(HP)2Mo12O42]4- Electrochemical reduction of yellow-colored [(HP)2Mo12O40]4- to a blue species is useful as a direct determination of HPO32-. The spectroscopic, structural and chemical characteristics of the individual complexes are elucidated. The present and future uses of MoO3 as an analytical reagent are discussed on the basis that Mo6+ centers (Lewis' acids) in the molybdate-frameworks coordinate to various types of hetero-ions (Lewis' bases). The reactivity of several phosphorus compounds toward MoO3 reagent is similar to the interaction of the same phosphorus compounds with hydrous iron(III) oxide.View full abstractDownload PDF (3260K) -
Yasuhiro KATSUOKA, Junjiro HAYASHI, Masaaki YAMADA, Toshiyuki HOBO1991 Volume 40 Issue 10 Pages 525-529
Published: 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA new chemiluminescence (CL) system was developed for the selective determination of adrenaline by the flow-injection method. Light emitted from the oxidation of adrenaline with Fenton's reagent was enhanced in alkaline solution containing a small amount of acetonitrile. The detection limit (S/N=2) was 3 × 10-8 M (20μl sample injection volume) and the linear dynamic range extended over three orders of magnitude. The relative standard deviation (n=10) was 4.2% for the CL signals of 5 × 10-7 M adrenaline. The CL system proposed was very selective; other catecholamines and catecholamine metabolities gave no light emission. At 1 × 10-3 M, metanephrine produced a CL signal of 66% intensity compared to the signal for 1 × 10-3 M adrenaline. The method was applied to practical samples. The CL reaction mechanism was also discussed.View full abstractDownload PDF (844K) -
Tsuyoshi NOMURA, Hiroyuki MORI1991 Volume 40 Issue 10 Pages 531-535
Published: 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA method is proposed for the selective determination of creatinine, based on the use of a membrane electrode of lead phosphate glass containing silver oxide as an ammonia sensitive sensor and a CPG-10 glass beads column which has been immobilized with the creatinine-deiminase enzyme. Creatinine-deiminase specifically catalyzes the conversion of creatinine to ammonia and N-methylhydantoin. Lead phosphate glass containing silver oxide shows an electrode response for monovalent anions and ammonia but not for cationic species. Therefore, the ammonia produced in the enzymatic reaction of creatinine is measured potentiometrically with this electrode. The flow system employed comprised a pump, a sintered ceramic filter, a Rheodyne sample injector, a treated enzyme column and an anion selective glass membrane flow cell. When carrier solution for creatinine was applied to a 10-3 M NaOH-10-3 M Na2SO4 system at pH 10.0 and 30°C, its peak height was in nearly linear relation to the logarithmic concentration of creatinine ranging from 0.14 to 5.66 mg/25 ml, for injections of 100 til samples. The most suitable temperature range was 2530°C. About 90% of the original responsiveness was retained after three months, but the activity was lost after 35 d at temperatures above 40°C.View full abstractDownload PDF (704K) -
Mitsuko KAWAMOTO, Hidetoshi ARAKAWA, Masako MAEDA, Akio TSUJI1991 Volume 40 Issue 10 Pages 537-541
Published: 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA highly sensitive assay system for NADH using an enzyme cycling method was developed. The proposed method is simpler and more rapid than the previous enzyme cycling method. In this method, alcohol dehydrogenase (ADH) and malate dehy-drogenase (MDH) is used as a cycling reaction, and malic enzyme as an indicator reaction enzyme. Alkaline phosphatase (ALP) was determined using this method; it was also applied to the determination of 17α-hydroxyprogesterone (17-OHP) and/or human chorionic gonadotropin (hCG). The procedure was as follows : to an assay tube was added 10μl of an NAD+or NADH solution and 50 μl of an enzyme cycling solution containing 4 U/ml ADH, 6 U/ml MDH, 0.6 mM oxalacetate and 0.36 M ethanol; the resulting solution was incubated at room temperature overight. Then, 100μl of an indicator solution containing 200μM of NADP+, 1 mM of MgCl2 and 0.625 U/ml of malic enzyme were added to the assay tube, which was subsequently incubated at room temperature for 20 min. The reaction mixture was immediately mixed with 500 μl of 1-methoxy-phenazinium methylsulfate (5×10-6 M) ; after standing for 30s at room temperature, 500μl of an isoluminol (2.4×10-4M)/microperoxidase (1×10-6 M) (1:1) solution wasView full abstractDownload PDF (896K) -
Shinkichi YAMADA, Naoto TAKAI, Motoshi NAKAMURA, Shigeru NAKAMURA1991 Volume 40 Issue 10 Pages 543-547
Published: 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe kinetics and thermodynamics of ligand substitution reactions of niobium and tantalum complexes involving hydrogen peroxide as an auxiliary complexing agent with morin have been studied fluorometrically. Under selected conditions in which the concentration of hydrogen peroxide and the pH of the reaction solution were 3.2×10-2 M and 3, respectively, the fluorescence intensity of the niobiummorin complex was about 30-times higher than that of the corresponding tantalum complex and the rate of substitution involving niobium was about 900-times faster than that involving tantalum. These differences allow a kinetic separation of niobium from tantalum; the more reactive niobium was selectively determined up to 1×10-5 M with a detection limit of 6×10-8 M by a linear extrapolation method. In the determination of 4×10-6 M of niobium, the presence of a 16-fold amount (by molarity) of tantalum could be tolerated.View full abstractDownload PDF (784K) -
Yukiko OKADA, Shoji HIRAI1991 Volume 40 Issue 10 Pages 549-555
Published: 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSIt is well known that alpha-particle emission from traces of uranium or thrium in semiconductor materials causes damages to semiconductor function. To produce high quality semiconductor materials, it is necessary to develop highly sensitive analytical methods for uranium and thorium. High quality silica with low uranium and thorium content was analyzed by radiochemical neutron activation analysis. The samples were irradiated by the Musashi Institute of Technology Reactor (thermal neutron flux 1012n cm-2 s-1) and were subjected to anion exchage chromatography and a LaF3 coprecipitation method.By this method, many interfering radioactive isotopes, 24Na, 42K, 122Sb, 124Sb, 182Ta were removed by anion exchange chromatography, and 187W was removed by the LaF3 coprecipitation method. The lower limits of the determination were found to be 3 ppt (10-12 g/g) and 6 ppt (10-12 g/g) for uranium and thorium, respectively. This method is useful for the determination of uranium and thorium in high purity silica as semiconductor materials.View full abstractDownload PDF (1058K) -
Yutaka ASAHI, Masami TANAKA, Mayumi SUGIMOTO1991 Volume 40 Issue 10 Pages 557-562
Published: 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe nonaqueous titration of 8 drugs in Japanese Pharmacopoeia was investigated in place of Kjeldahl's method and diazotization titration. The drugs were determined directly by potentiometric titration with perchloric acid in a mixture of acetic anhydride and glacial acetic acid. The titration curves (the first and second derivative curves after smoothing) were recorded on an automatic titrator assisted by a microcomputer. Urea (I), pyrazinamide (II), ethenzamide (III), acetaminophen (IV), neostigmine methylsulfate (V) and procaine hydrochloride (VII) were determined by titration in acetic anhydride. Ethyl p-aminobenzoate (VIII) was determined by titration in glacial acetic acid. Primidone (VI) was too weak a base to be determined by this method. The standard deviation of this method was 0.12% (VII)0.34% (III) and 0.92% (IV). Neostigmine bromide (X), however, reacted with 1 eq. perchloric acid, 3 mol of (V) reacted with 1 eq. perchloric acid since methylsulfate decomposed to methyl acetate and sulfuric acid. The basic center of pyrazinamide was determined to be both nitrogens of pyrazine owing to the high field shift of 3-C and 6-C on NMR by protonation.View full abstractDownload PDF (888K) -
Takushi ITO, Akira MURATA1991 Volume 40 Issue 10 Pages 563-566
Published: 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSHafnium reacts with 2-methyl-3, 7-dihydroxychromone in media of pH<3 up to 6 M hydrochloric acid to form a water-soluble complex. The complex shows an intense fluorescence in 0.1-4 M hydrochloric acid solution. Excitation and emission maxima of the complex are 350 nm and 421 nm, respectively. Hafnium can be determined in the range of 4-200 ng/ml in 1 M hydrochloric acid containing 50% methanol. EDTA, oxalate and fluoride give serious negative errors. Zirconium does not interfere up to 10-fold amounts. The molar ratio of hafnium to the reagent was 1 : 1 in 1 M hydrochloric acid and 1 : 3 at pH 2.0. The relative fluorescence intensities of the hafnium complexes of 3-hydroxychromone, 2-methyl-3, 7-dihydroxychromone and 3, 7-dihydroxyflavone are 25, 100 and 172, respectively.View full abstractDownload PDF (564K) -
Toshiaki NOMURA, Kazutake TAKADA1991 Volume 40 Issue 10 Pages 567-570
Published: 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSPiezoelectric quartz crystal (PQC) having no evaporated metallic electrodes (quartz plate) oscillated in gases when an oscillator was connected to platinum plates set on both sides of the quartz plate. The frequency of the quartz plate increased with increasing the distance between the plates. The frequencies shifted with the densities of gases and the mass adsorbed onto the plate just as in normal PQC. The system was named an electrode-separated PQC. The electrode-separated PQC with a Teflon-coated quartz plate could be used to detect the relative humidity in gases.View full abstractDownload PDF (605K) -
Shukuro IGARASHI, Kazumi YOSHIDA, Takao YOTSUYANAGI1991 Volume 40 Issue 10 Pages 571-573
Published: 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSBased on the color reaction with titanium(IV), a simple spectrophotometric method for the determination of 10-5 mol dm-3 levels of DFB was developed. The recommended procedure was carried out as follows: an aliquot of a sample solution (15 cm3) containing less than 4.4 mg of Desferrioxamine B mesylate was taken into a 25 cm3 volumetric flask, and 4 cm3 of a 1 mol dm-3 hydrochloric acid solution and 5 cm3 of a 1 × 10-3 mol dm-3 titanium(IV) solution were added and the mixture was diluted to the mark with water. After 5 min, the absorbance at 356 nm was measured against water. The calibration curve was linear over the DFB concentration range 2× 10-5-2 ×10-4 mol dm-3. The relative standard deviation was 0.65% for, [DFB]T=1× 10-4 mol dm-3 (12 determinations). The detection limit was 1.31 × 10-6 mol dm -3 (S/N= 2). For the determination of 4× 10 -5 mol dm-3 DFB, diverse ions were tolerated up to 1000-fold molar excess of NO3-, Cl-, Cl04-, SO42-, K(I) and Na(I); they were tolerated up to a 100-fold molar excess of EDTA, glycine, Al(III), Co(II), Cu(II), Pb(II) and Zn(II), respectively. For the determination of 4 ×10-5 mol dm-3 DFB, equal amounts of Fe(III), V(V) and Mo(VI) interfered; however, a 50-fold molar excess of Fe(III) was tolerated with the use of [HNO3]T = 1.5 mol dm-3 instead of [HCl]T= 0.16 mol dm -3.View full abstractDownload PDF (395K) -
Hideji SATOH, Yoichi KIKUCHI, Toshio SUZUKI, Kiyoshi SAWADA1991 Volume 40 Issue 10 Pages T167-T170
Published: 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA highly sensitive spectrophotometer system equipped with a phase separator and a flow-through absorbance cell was applied to the solvent extraction/spectrophotometric determination of trace amounts of copper with sodium diethyldithiocarbamate (Na·DDTC). A linear calibration curve was obtained at the absorption maximum of Cu-DDTC complex (436 nm, ε=13000 in carbon tetrachloride) up to 4.0 ppb copper. The detection limit of copper was 0.05 ppb. The RSD was 0.83% for 10 runs at 4.0 ppb of copper at 34-fold concentration factor. By use of masking agents, coexisting ions up to the environmental water level did not interfere with the determination of copper. Applying this method to the determination of copper in land waters, values of 1.2-2.0 ppb copper were obtained.View full abstractDownload PDF (721K) -
Norio ICHINOSE, Kyoko ADACHI, Masahito YAMADA, Akira HISHIDA, Nishio H ...1991 Volume 40 Issue 10 Pages T171-T173
Published: 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSSolid fluorometry using a flying spot scanner is applied to the determination of urinary uranium of a rabbit which developed acute renal failure following intravenous administration of uranium as uranyl acetate. After decomposing a rabbit urinary sample { U(VI) 0.4 μg} using conc.HNO3 and conc.HClO4, 10 ml of the solution containing uranium(VI) adjusted to pH 3.7-4.0 are shaken vigorously for about 30 min with 1 ml of 4× 10-2 mol/l trioctylphosphine oxide-benzene solution and 1 ml of 2 × 10-2 mol/l benzoic acidbenzene solution in a 50 ml separatory funnel. A spot (0.55μl) of the extract is dropped onto a TLC plate (10 × 10 cm) of Silica Gel-60 previously dried at 110°C for 1 h. After drying it at 150°C for 1 h and cooling, the fluorescence intensity of the spot (6 mm dia) is then measured by a flying spot scanner equipped with a xenon lamp at fluorescence excitation of 245 nm and fluorescence emission of 498 nm (filter type). Using this method, trace amounts of uranium in rabbit urine samples could be determined, with a recovery rate of 95.4 % and a standard deviation rate of 5.9%.View full abstractDownload PDF (482K) -
Hiroyasu YOSHIKAWA, Takanori AKIYOSHI, Kohji TSUKADA1991 Volume 40 Issue 10 Pages T175-T178
Published: 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSTrace amounts of lead in zinc and zinc-aluminium alloys were determined by ICP-AES after coprecipitation with manganese dioxide. After the sample (1.000 g) was dissolved in 7 M nitric acid, the sample solution was adjusted to pH 2.0-2.5 with ammonium hydroxide solution. For manganese dioxide precipitation, manganese nitrate solution and permanganate solution were added to the test solution. After filtration, the precipitate was dissolved in 2 M nitric acid and a small amount of hydrogen peroxide. Quantitative recovery of lead required at least 30 mg of the resulting manganese dioxide precipitate. The recovery of lead was dependent on the pH value of the sample solution and quantitative above pH 2. On the other hand, although 99.7% of the zinc content could be recoverd from the resulting precipitate in the tested pH range of 0.2-3.8, that of aluminium decreased with increasing pH value due to increased formation of aluminium hydroxide. Lead analyses obtained by the present method showed good agreement with the certified values.View full abstractDownload PDF (607K) -
Yutaka HAYASHIBE, Minoru TAKEYA, Yasumasa SAYAMA1991 Volume 40 Issue 10 Pages T179-T182
Published: 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe reversed flow injection method has been examined for the determination of copper in high salt concentration (zinc electrolyte) solutions used for wet zinc refining. The sample solution containing ca. 150 gZn 1-1 is introduced continuously into the analytical system, diluted six-fold with 0.25 M sulfuric acid, and its pH is adjusted to 5 by mixing with 2 M acetate-0.5 M citrate buffer solution. The chromogenic reagent solution {0.05% (w/v) sodium bathocuproinedisulfonate-10% (w/v) L -ascorbic acid} is then injected into the sample solution stream and the absorbance of copper(I)-bathocuproinedisulfonato complex is monitored at 525 nm. A calibration curve is constructed by using solutions prepared by adding various increments of the standard copper solution to defined aliquots of the real sample solution of which the copper concentration had previously been determined by ICP-AES. The analytical results are in good agreement with those obtained by ICP-AES. The proposed system is operated automatically by a personal computer and allows 50 samples to be analyzed per hour with a R.S.D. of 2.0% at the 0.5 μg ml-1 level and a detection limit of 0.1 μg ml-1.View full abstractDownload PDF (737K) -
Yoshinori UWAMINO, Hisashi MORIKAWA, Akira TSUGE, Yasuo IIDA, Toshio I ...1991 Volume 40 Issue 10 Pages T183-T187
Published: 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSSince pulverized samples are severely contaminated, several decomposition methods were examined to determine trace impurities in sintered alumina and zirconia samples. A lump (ca. 0.3 g) of sintered sample was decomposed with 10 ml of (1+ 2) surfuric acid (alumina and some zirconia), and with a mixture of 0.5 ml of hydrofluoric acid-9.5 ml of (1+2) sulfuric acid (zirconia) in a Teflon pressure vessel at 230°C. The proposed methods were applied to some commercial samples, and impurities were determined by ICP-AES.View full abstractDownload PDF (936K)
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