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Volume 30, Issue 9
Displaying 1-20 of 20 articles from this issue
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Yohichi SUZUKI, Kenji ONO, Ichiroh ANAZAWA1981 Volume 30 Issue 9 Pages 557-560
Published: September 05, 1981
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe NMR spectra of OH protons of phenol mixtures were measured in acetone solution containing a small amount of various metallic salts. The absorption line width of OH protons showed remarkable change with the addition of a small amount of nitrate or halide of metals, such as Mg, Fe, Co, Zn, Ag, Cd, Sn, Sb, Hg, and a well-resolved NMR spectrum of each OH proton was obtained by the addition of adequate amount of metallic salt. The adequate amount of metallic salts was different from their type, when metallic salts whose ligands were halogen or nitrate ions were added. The effect of addition of metallic salts was affected by the type and the number of ligands, and it was found to be more efficient when metallic salts having many ligands of larger electronegativity were added. Furthermore, the amount of salts varies quantitatively with pKa value of phenols, the concentration of phenols and the temperature. These results mean that the amount of addition is parallel with proton exchange rate of OH protons. From the results above mentioned, it is considered that the remarkable change of the absorption line width of OH protons is caused by ligand.View full abstractDownload PDF (746K) -
Effect of modification of glassy carbon electrode on electrochemical determination of catecholaminesHideo IMAI, Hisanobu YOSHIDA, Tsutomu MASUJIMA, Megumi OWA1981 Volume 30 Issue 9 Pages 561-565
Published: September 05, 1981
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSAn electrochemically modified glassy carbon(GC) electrode was applied to electrochemical detection of catecholamines (CA). Suitable modification was attained by the anodic oxidation of GC in 0.1 M malate or citrate solution containing 0.1 M Na2SO4 (pH 3.0) at 1.4 V vs. Ag/AgCl in 40 min. By this treatment the oxidation potential of dopamine was decreased by 0.21 V and the peak current was increased by about five times, simultaneously increase in the charging current being accompanied. The activation resulted in increase of the effective surface area and introduction of CO and OH groups on the GC surface. A curvilinear calibration plot of the peak current of CA in the cyclic voltammetry indicated strong adsorption of CA on the activated electrode. Both the limiting current in the rotating disc electrode voltammetry and the current flowing through a thin-layer electrochemical cell at a constant applied voltage gave a good straight line calibration plot. The determination of CA as low as 10 pmol or less could be achieved in 20 min. with c.v. value of about 3 % by HPLC electrochemical detection using TSK Gel LS410, 7.5 mm ID and 75 mm L column, and reversed phase elusion at 20 °C with phosphate buffer (pH 2.3) under flow rate of 0.7 ml/min. The re-activation of a deteriorated electrode was easily performed by changing the eluent to malate or citrate solution for activation.View full abstractDownload PDF (923K) -
Yukio MINAMI, Toshiyuki MITSUI, Yoshikazu FUJIMURA1981 Volume 30 Issue 9 Pages 566-568
Published: September 05, 1981
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSLow molecular weight ketones and aldehydes (such as acetone, cyclopentanone, ethyl methyl ketone, propionaldehyde, butylaldehyde, formaldehyde) were determined with good precision by atomic absorption spectrophotometry (AAS). The recommended procedures are as follows : 1 ml of sample solution {(0.012.01) mg/ml} is added 2 ml of thiosemicarbazide solution (thiosemicarbazide 11 mg/ml) and 1 ml of copper acetate solution (copper acetate 15 mg/ml). The mixture is warmed on a water bath for 4 min at 70°C, and then cooled. The mixture is shaken with 5 ml of benzene for 5 min, and the two liquid layers are by centrifugation. The benzene layer is dehydrated and added ethanol (1:1). Copper in the solution is measured by AAS. Ten to fourteen folds (material/acetone, mg/mg) of Co2+, Ni2+, Ag+, Zn2+, isopropylamine and monochlorobenzene interfered markedly with the determination but 22 to 25 folds of Mg2+, ninhydrin, isatin, phenanthraquinone, phenylacetaldehyde, p-dimethylbenzaldehyde, cinnamaldehyde, or salicylaldehyde did not.View full abstractDownload PDF (419K) -
Yasushi TANAKA, Hiroshi NAKANISHI1981 Volume 30 Issue 9 Pages 569-573
Published: September 05, 1981
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe method involves purification of dodecylbenzenesulfonate(DBS) on Sephadex LH-20 gelfiltration and its quantitative analysis by high performance liquid chromatography(HPLC). This method allows the selective analysis of DBS without interference by Methylene Blue active substances. Biological sample was mixed with anhydrous sodium sulfate and extracted with methanol in a Soxhlet extractor. Sediment sample was refluxed with methanol in a round bottom flask on a water bath. The extract was concentrated on a water bath and made up to 2 ml. An aliquot of the extract (1 ml) was subject to Sephadex LH-20 gelfiltration using 0.2 M ammonium sulfate in 50 % methanol as eluate at the flow rate of 0.5 ml/min. The eluate of 70 ml to 160 ml was collected and concentrated to 50 ml on a water bath. The concentrated solution was transfered to a separatory funnel and DBS was extracted with MIBK to remove ammonium sulfate. The MIBK layer was taken into a volumetric test tube and evaporated to dryness in a water bath. The residue was dissolved by addition of an appropriate volume of water. The resultant solution was injected into HPLC. Conditions for HPLC were as follows : column, PCH-05/S2504 (4 mm i.d. × 25 cm); mobile phase, 0.01 M pottassium dihydrogen phosphate pH 2.5 in 50 % acetonitrile; flow rate, 1 ml/min; column temperature, ambient; detector, UV 225 nm. Standard deviation and coefficient of variation were 0.67% and 1.1 %, respectively. The recoveries of this method were (96.898.7) % for sediment sample and (68.681.8) % for biological sample. The minimum determinable amounts of DBS were 0.07 μg/g in sediment and 0.40 μg/g in biological sample (Himetanishi).View full abstractDownload PDF (743K) -
Tadao OKUTANI, Takayuki HAYASHI, Satori UTSUMI1981 Volume 30 Issue 9 Pages 573-577
Published: September 05, 1981
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSAn extraction-spectrophotometric method for the determination of cyanide ion by the use of isonicotinic acid-pyrazolone as a coloration reagent was studied. This method involves the extraction of the coloring matter, which is formed by the reaction of cyanide ion with isonicotinic acid-pyrazolone reagent, into butyl acetate containing capriquate. The determination procedure is as follows. A 40 cm3 of neutralised sample solution containing (0.051)μg of cyanide ion, 5 cm3 of phosphate buffer solution (pH 7.5) and 0.5 cm3 of 1 % Chloramine T solution are poured into a separating funnel. After standing for about 5 min, 4 cm3 of sodium isonicotinate-pyrazolone reagant solution is added, and then, the solution is allowed to stand for about 80 min at 20°C. The formed coloring matter is extracted with 5 cm3 of 1 % capriquat-butyl acetate solution. The organic phase is separated and then a little turbidity in organic phase is removed by the centrifugation. The absorbance of the coloring matter in the organic phase is measured at 650 nm against water. This method can be used to determine cyanide ion ranging in concentration from 1.3 ppb to 25 ppb in 40 cm3 of a sample solution. The coefficient of variation of the determination was found to be 0.8 % by means of 10 measurements using 0.5 μg of cyanide ion. The presence of small amounts of formaldehyde, sulfide, thiosulfate, sulfite, iodide and bromide interferred with the determination of cyanide ion.View full abstractDownload PDF (825K) -
Yoshimi SASAKI, Minoru KAWAE1981 Volume 30 Issue 9 Pages 577-581
Published: September 05, 1981
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA selective method is described for the determination of iron and copper in river water by substitution extraction with aluminum cupferrate[Al(Cup)3]. The iron and copper are extracted with Al(Cup)3 in methyl salicylate(MeS), the resulting MeS phase is directly subjected to atomic absorption spectrophotometry. MeS is far less soluble in water compared to MIBK or butyl acetate usually used and enables to concentrate trace metals up to 100 times. A sample solution of (20500)ml containing iron(III) (0.360) μg and copper(II) (0.140) μg is taken in a separating funnel. The pH of the solution is adjusted to 3.55.0 with acetate buffer, and 5.0 ml of 0.01 M Al(Cup)3-MeS is added. The mixture is shaken for 5 min, the absorbance of the MeS phase in air-acetylene flame is measured at 248.3 nm for iron and 324.7 nm for copper. Usual foreign cations and anions do not interfere except substances such as citrate. The interference can be avoided by boiling in the presence of sulfuric acid and potassium permanganate. After the excess of permanganate is decomposed with hydrogen peroxide, the procedure as described above is applied. In order to separate the suspended particle, the sample solution of river water was filtered with 0.45 μm milliporefilter. Iron and copper at ppb-level in the filtrate were determined by the presented method, and satisfactory results were obtained.View full abstractDownload PDF (769K) -
Toshitaka HORI, Tadafumi ITOH, Satoshi OKAZAKI, Taitiro FUJINAGA1981 Volume 30 Issue 9 Pages 582-587
Published: September 05, 1981
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA flow-coulometric method using a column electrode packed with glassy carbon fibre has been developed for the determination of dissolved silicate in natural waters. The flow-electrolysis system proposed here was devised as follows: Each 100 μl of silicate sample was injected into a steady flow of 4 ml/min of a carrier solution composed of 0.05 M sodium molybdate and 0.5 N hydrochloric acid, and was led to a "Mixing and Reaction Coil" kept around 80 °C, where β-silicomolybdate complex formed instantaneously (within 50 s), excluding formation of α-complex. Beta-complex thus formed was entirely carried into a "Flow electrolysis Cell" and reduced with two electrons per molecule at a potential of +0.37 V vs Ag-AgCl. The reduction current was recorded automatically and the amount of silicate was determined from the net electricity consumed for the electrolysis. By operating the flow-electrolysis system described above, it was found that silicate samples in the concentration range from 4 × 10-5 M to 1× 10-3 M can be analyzed. within two min per one sample with relative standard deviations smaller than 2 %. The present method was applied to the determination of dissolved silicate in river water and tap water, and the results were compared with those obtained by the conventional "heteropoly blue" spectrophotometric method. Both of the results well coincided with each other, indicating that the present method can really give the amount of so-called "dissolved silicate" and/or "molybdate reactive silicate".View full abstractDownload PDF (1070K) -
I. Database on complexation reactionsNobuyuki TANAKA, Etsuko KIKKAWA, Takako MATSUDA, Akifumi YAMADA1981 Volume 30 Issue 9 Pages 587-594
Published: September 05, 1981
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA computer database on complexation reactions has been studied for the purpose of its use in analytical chemistry. The database management system GOOD, which was developed not only for the on-line data manipulation such as data storage and retrieval but also for the on-line database operation such as generation, modification and deletion, has been adopted for the formation of the database. After careful examination of database structure, it is decided that the database CORMEC (Complexation Reactions of Metal Complexes) should be composed of six tables, ECCORS, RACOR, DICCORS, NALCOR, LICOR and CODCOR, which deal with the data of equilibrium constants and rate constants of complexation reactions, those of dissociation constants of ligands, names of ligands, literatures on complexation reactions and compilers of data, respectively. For ECCORS and DICCORS, only selected values were stored. In addition to the formation of the database, computer programs which can be applied to the use of database have been developed. A retrieval-calculation program for conditional stability constants, and retrieval-drawing programs for conditional stability constant-pH curves, for titration curves of complexation titrations, and for concentration-time curves of complexation reactions have been completed and applied in various cases. Those programs have proved to be useful in deciding the condition for complexation titration.View full abstractDownload PDF (1390K) -
Susumu KUBO, Shigetoshi YAMAGUCHI, Atsushi MIZUIKE1981 Volume 30 Issue 9 Pages 594-598
Published: September 05, 1981
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSMicroscale decomposition and separation techniques, which are effective for minimizing quantities of reagents and wastes as well as time, are developed for the determination of vanadium at the low ppm level in titanium(IV) oxide powder by graphite furnace atomic absorption spectrometry. A 10 mg sample is decomposed in a 2 ml closed Teflon vessel with 40 μl of 28 M hydrofluoric acid at 160°C. The solution is neutralized, and vanadium is extracted with 100 μl of chloroform as diethyldithiocarbamate from ca. 1 ml of aqueous phase at pH (46). The organic phase is quantitatively separated from the aqueous phase by centrifugation followed by filtration through a hydrophobic Teflon filter of 0.5 μm pore size and evaporated to dryness at (4050)°C. The residue is dissolved in 100 μl of 7 M nitric acid, and a 30 μl aliquot is placed in a graphite furnace for atomic absorption spectrometry at 318.4 nm. A few ppm of vanadium in titanium(IV) oxide microsamples is determined by the proposed method with an accuracy of ca. 10 %. The procedure is easy, and the time required for a determination is less than 1 h.View full abstractDownload PDF (914K) -
Nobuhiro NONAKA, Hideo HIGUCHI, Hiroshi HAMAGUCHI, Kenji TOMURA1981 Volume 30 Issue 9 Pages 599-604
Published: September 05, 1981
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSDry ashing technique has been considered to cause potential errors due to loss of elements by volatilisation or by reaction with the vessel. To obtain an overall view of elemental loss, the dry ashing was applied to the standard reference materials such as Orchard leaves(NBS) and Bamboo leaves. The ashing condition was as follows; The temperature varied from 200 °C to 800°C by stepwise heating and the duration of heating at each temperature was 24 h. Concentrations of 25 elements in a sample were determined by means of atomic absorption spectrometry and neutron activation analysis using a Ge(Li) detector. The results obtained were as follows; (1) The losses for alkali elements were dependent on crucible materials and sample species. The losses increased with temperature and they were serious when a silica dish was used. (2) The loss for mercury was found above 110 °C and simply increased with temperature. On the other hand, chlorine, bromine, selenium and chromium showed complicated patterns in which the first losses occurred at 200 °C, no additional losses being observed at each following step of heating between 200°C and 450°C, and they increased again above 500°C. (3) The losses for arsenic and antimony occurred at 200°C, but any losses could not be ob served above 200°C. (4) No losses were detected over the temperature range studied for alkaline earths, rare earths, vanadium, manganese, iron, cobalt, zinc and aluminum.View full abstractDownload PDF (1123K) -
Wataru ISHIBASHI, Ryoji KIKUCHI, Kozo YAMAMOTO1981 Volume 30 Issue 9 Pages 604-608
Published: September 05, 1981
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA method for the simultaneous determination of chlorine and fluorine in tantalum powder {condenser grade; particle size (0.070.15) mm} by ion chromatography combined with pyrolysis was investigated. A Dionex Model 14 Ion Chromatograph with a Dionex 030170 anion separator column and 030015 cation suppressor column was used. The apparatus for the pyrolysis consists of a fused silica reaction tube (diameter 30 mm, length 600 mm), a bubbler (volume 25 ml), a openning type electrical furnace (max. 1500 °C), and a platinum boat (12 mm×10 mm×60 mm). Conditions for the pyrolysis and the ion chromatography have been investigated, and the optimum conditions were established. The recommended procedure is as follows. Set the bubbler containing 20 ml of 6 mM Na2CO3 solution to the apparatus for the pyrolysis and flow the carrier gas (nitrogen) first through the water heated at 90°C to saturate with water vapor and then through the reaction tube at 350 ml min-1 Put 0.5 g of sample powder into the platinum boat, and insert it into the reaction tube electrically heated at 800°C (chlorine and fluorine are extracted from sample, led to the bubbler with carrier gas, and absorbed in the absorbent, 6 mM Na2CO3 solution). After 15 min, transfer the absorbent to a 50 ml volumetric flask, add 20 ml of 7.5 mM NaHCO3 solution to the solution, and dilute to the mark with water. Introduce a 100 μl portion of the solution into the chromatograph (2.4 mM Na2CO3-3.0 mM NaHCO3 solution is used as eluent), and record the ion chromatogram. In the case of sample size of 1.0 g, the detection limit was 1 ppm both for chlorine and for fluorine, and the coefficient of variation was 6 % for chlorine and 2 % for fluorine.View full abstractDownload PDF (902K) -
Eiichi KITAZUME, Kunihiro YAGI1981 Volume 30 Issue 9 Pages 608-612
Published: September 05, 1981
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSSpectrophotometric determination of arsenic at the microgram level, based on formation of an arsenicantimony-molybdenum ternary complex was studied. It was found that an [H+]/[MoO42-] ratio of 90±10 was optimal for stable complex formation in an (0.0010.003) M molybdate solution at the room temperature. The As(V) : Sb : Mo ratio in the complex was estimated through the continuous variations method, and elemental analysis, to be 1 : 2 : 8. The precision was 2.5 % at 2 μg of arsenic, and the lower limit of determination(Absorbance=0.01) was 0.2μg/5 ml. Phosphorus affected arsenic(V) determination even in low concentrations. However, arsenic(III) and germanium did not interfere with the determination until they existed in the same concentrations as arsenic(V), and silicon did not interfere with even in concentrations of a hundred times that of arsenic(V). This method was successfully applied to the determination of total arsenic at the microgram level in semiconductor silicon dioxide film.View full abstractDownload PDF (907K) -
Sinsuke YAMASHITA, Sanae IKEDA, Mayumi OHE, Hiromu SATAKE, Takuya YAMA ...1981 Volume 30 Issue 9 Pages 612-616
Published: September 05, 1981
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSAs an example of the analytical application of laser Raman spectroscopy, the analysis of ammonium thiocyanate-thiourea mixture system was investigated in order to determine the amount of each component in solid state. In solid state of ammonium thiocyanate, the CN stretching band was splitted into two lines presumably due to the SCN group bonding ammonium ion through the nitrogen or the sulfur and/or both. The band frequency corresponding to N-bonded complex is lower than that corresponding to S-bonded complex. Raman band which is due to the S-bonded complex is gradually decreased in intensity by increasing the added amount of thiourea, because number of the linkage between N(ammonium) and S(thiocyanate) may be decreased. The area ratio of both Raman lines are strictly related to the ratio of amount of both components in the range of (0.21.0) molar ratio.View full abstractDownload PDF (607K) -
Norinobu YONEHARA, Masaakira KAMADA, Kazuo FUKUNAGA1981 Volume 30 Issue 9 Pages 617-619
Published: September 05, 1981
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSBy application of freeze concentration, the chloride content in distilled and redistilled waters was determined as a material characterizing the water qualities. The sample solution was carefully frozen in a polyethylene bottle with stirring, followed by the determination of chloride in the resulting concentrate. Freezing of 5 1 sample solution required about 8 h at -15°C to -18°C. The concentrated solution was contaminated with chloride in the atmosphere during the procedure. The amount of chloride originally present in the sample was obtained by correcting for the contamination value determined separately as follows: After removal of the concentrated solution obtained in the first freeze concentration, the ice remained was melted and the resulting water was repeatedly concentrated several times. The average contamination level was affected not only by the conditions of ambient air but also even by the circumstances of neighbouring laboratories. In order to prevent the chloride contamination, the freeze concentration was done by using a bottle covered with a polyethylene disk with a center hole to fit the stirring shaft through it. The values of chloride obtained were lower and more reproducible than those in uncovered procedure. The average concentrations of chloride in distilled and redistilled waters were 3.6 ppb and 1.6 ppb, respectively.View full abstractDownload PDF (623K) -
Norinobu YONEHARA, Masaakira KAMADA1981 Volume 30 Issue 9 Pages 620-622
Published: September 05, 1981
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe effect of the total concentration of solutes on the recovery of a certain microchemical constituent in freeze concentration has been studied. When the sample solution is slowly frozen, formation of transparent ice starts from the vessel wall. The solutes are concentrated in the remaining solution and when the amounts of the solutes are small, the recoveries are close to 100 % even after a 100-fold concentration is achieved. However, when the total solute concentration in the remaining solution has reached a certain level (about 0.04 mol/dm3), the ice eventually starts to occlude the solutes and becomes cloudy, in such a region the solute recovery suddenly falls down by a further progress of freezing and nearly no further concentration is achieved when the total solute concentration reaches about 0.1 mol/dm3 due to increase in the occlusion of the solute in the ice. Under such conditions, the recovery of the coexisting microchemical constituent in the solution is also low. The freeze concentration method is applicable to solutions in which the total solute concentration is lower than 0.01 mol/dm3.View full abstractDownload PDF (554K) -
Toshiaki FUJII1981 Volume 30 Issue 9 Pages 622-624
Published: September 05, 1981
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSRecently, the formula of composting municipal refuse and sewage sludge attracts attention of the public. But the determination of ripeness depends on experience because the marker of it is not yet known. The change of composition of gases obtained by pyrolysis of fermenting compost was studied by pyrolysis gas chromatography. The results were as follows. (1) The marker of ripeness could be detected by PGC. (2) The changes of composition of pyrolysis gases from C9 to C10, from C12 to C13, from C14 to C15 and from C19 to C20 revealed the process of fermentation. (3) The changes of composition of pyrolysis gases from C12 to C13 and from C19 to C20 revealed the process of maturing.View full abstractDownload PDF (481K) -
Hiroko FUJINO, Kaname MUROI, Sadao MORISHITA1981 Volume 30 Issue 9 Pages 624-626
Published: September 05, 1981
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSWater contents in diverse electric insulating papers were determined by the following methods; (A) nitrogen carrier extraction (105°C and 130°C)-Karl Fischer titration, (B) methanol extraction-Karl Fischer titration, and (C) oven drying weight loss at 105°C ( JIS C 2111) and 130°C. Except for JIS, determined values were in good agreement. Values obtained by JIS were smaller than those obtained by the others. (A) is the most advantageous because of the short time {(1015) min} required for the determination and the accuracy of obtained values.View full abstractDownload PDF (492K) -
Daijiro YAMAMOTO, Shozaburoh HIRAOKA, Misa HIKAWA1981 Volume 30 Issue 9 Pages 626-628
Published: September 05, 1981
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSDiammonium ethylene-1, 2-bis(phenyldithiocarbamate) (DEP) reacts with copper(II) to form a waterinsoluble brown complex in aqueous solution in the pH range of 4.326.81, which can be extracted with chloroform. Based on the formation of the complex, an extraction-spectrophotometric method for determination of copper (II) has been developed. The recommended procedure is as follows: To a sample solution (5 cm3) containing copper(II), less than 20 μg was added 8 cm3 of Britton and Robinson buffer of pH 5.5, and then added 1 cm3 of 0.06 w/v % DEP-methanol solution. The copper(II) chelate formed in the solution was extracted with 5 cm3 of chloroform by shaking for 1 min. The absorbance of the organic phase was measured at 442 nm against the reagent blank. The apparent molar absorption coefficient of the complex was evaluated as 1.56 × 104 dm-3 mol-1 cm-1, and the calibration curve obeyed Beer's law over the concentration range from 0.1 μg cm-3 to 4.0 μg cm-3 of copper (II). The molar ratio of copper (II) to DEP in the complex was determined to be 1:2 by the continuous variation method. Various metal ions, such as cobalt(II), iron(II) and (III), lead(II), nickel (II), palladium(II), strontium(II), zinc(II), and so on, interfered. These interfering metal ions could be easily masked by EDTA.View full abstractDownload PDF (528K) -
Kazuo ISE1981 Volume 30 Issue 9 Pages 629-630
Published: September 05, 1981
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA method is described for the determination by atomic-absorption spectrophotometry of molybdenum in flotation tailings by using dichloromethane as solvent which is less poisonous than the commonly used chloroform. Little difference was observed between dichloromethane and chloroform in the determination of a standard molybdenum solution. It was found that dichloromethane was also an effective solvent for the determination of a very small amount of molybdenum in flotation tailings by Hutchison's procedure. The accuracy obtained by dichloromethane was comparable to that observed for chloroform; the variation coefficient being 2.3 % for dichloromethane compared with 1.5 % for chloroform.View full abstractDownload PDF (345K) -
Hisao MABUCHI, Yoshimitsu HIRAO1981 Volume 30 Issue 9 Pages T87-T91
Published: September 05, 1981
Released on J-STAGE: January 19, 2010
JOURNAL FREE ACCESSTo determine the mass correction factor(MCF) which is a factor to convert the observed raw ratio to the absolute value, CIT Pb shelf standard of California Institute of Technology and SRM-981 Pb standard of US National Bureau of Standards were measured with a 05RB type, surface ionization solid source mass spectrometer (ion beam radius 30 cm, 90° sector, max. acceleration voltage 10 kV) of JEOL Co. Ltd. installed in Tokyo National Research Institute of Cultural Properties. Using an electron multiplier as ion beam collector, our measurement showed larger correction factor than the factor of root mass (√m1/m2) hitherto used by some authors. Our MCFs were 1.01024 (±0.1%), 1.00411 (±0.05%) and 1.01022 (±0.05%) for the ratios of 206Pb/204Pb, 207Pb/206Pb and 208Pb/206Pb respectively. These factors were obtained by comparing observed raw values with the values by Catanzaro(1967) and Catanzaro et al. (1968) for the CIT Pb and SRM-981 respectively. The lead isotope ratios of four galena samples corrected with these factors were in excellent agreement with the reported values for these samples.View full abstractDownload PDF (778K)
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