All issues
Volume 36, Issue 3
Displaying 1-24 of 24 articles from this issue
- |<
- <
- 1
- >
- >|
-
Kazunobu TAKAHASHI, Yoshihiko OHYAGI1987 Volume 36 Issue 3 Pages 133-137
Published: March 05, 1987
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSA gas chromatographic method was studied for the determination of trace amount of tributyltin compounds in seawater and sediment. The reaction of tributyltin compound with hydrochloric acid gives tributyltin chloride (TBTC) quantitatively, which is sensitive to ECD. One ml of 12 M hydrochloric acid was added to a 1000 ml of seawater, and the solution was shaken with two 40 ml portions of hexane. The extract was washed twice with 25 ml portions of 0.06 M hydrochloric acid, dried over anhydrous sodium sulfate, and filtered. The resulted solution was concentrated, if necessary, as the sample for gas chromatographic determination. In case of sediment samples, tributyltin compounds were extracted with 100 ml of methanol and 1 ml of 12 M hydrochloric acid using Soxhlet's extractor (70°C/2 h). The extract was concentrated to 10 ml, and diluted by 100 ml of saturated sodium chloride solution. The resulted solution was shaken with two 30 ml portions of hexane, and the hexane phase was treated in the same way as the case of seawater sample. The GC conditions were as follows : column packing, 10% Thermon-HG on Chromosorb W 6080 mesh; column size, 3 m×3 mm i.d. stainless steel column; column temperature, 160 °C; injection and detector temperature, 300 °C; carrier gas, nitrogen, 60 ml/min; detector, ECD (63Ni). The recoveries of the overall performance of this method were 8491% for seawater samples and 8994% for sediment samples. The detection limits of TBTC were 0.6 μg/l in seawater and 0.03 μg/g in sediment.View full abstractDownload PDF (578K) -
Masahiro TAKEUCHI, Kazuko MIZUISHI, Hideo YAMANOBE, Yohya WATANABE1987 Volume 36 Issue 3 Pages 138-142
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSTo obtain reproducible peaks of tributyltin chloride (TBTC) in GC using an electron capture detector (ECD), the pretreatment of GC column with 0.1 M hydrochloric acid (HCl)-acetone solution and the simultaneous injection of 0.01 M HCl-acetone solution with sample solutions have been investigated, and the results were applied to the determination of tributyltin compounds in fish and shell-fish samples : Tributyltin compounds in the samples were determined by ECD-GC after converting to TBTC. Five grams of homogenized fish arid shell-fish was extracted twice with 70 ml of hexane-ethyl ether (3 : 1, v/v) mixture in the presence of HCl. The combined extract was poured into a Florisil column (3 g of Florisil and 2 g of anhydrous sodium sulfate), then 50 ml of acetone and 40 ml of hexane-ethyl ether-acetic acid (75 : 25 : 1, v/v/v) mixture were eluted. The latter eluate was collected in a pear-shaped flask, concentrated by a rotary evaporator, and 3 μl portion of the concentrate was injected, together with 2 μl of 0.01 M HCl-acetone solution, into a gas chromatograph equipped with {10% Thermon-HG on Chromosorb W (AW-DMCS), 2.5 m×3.2 mm i.d.} column pretreated with 100150 μl of 0.1 M HCl-acetone solution. The total content of tributyltin comopounds could be caluculated from the peak height of TBTC in the chromatogram. The recovery and the relative standard deviation of this method at 2.0 μg level of bis(tributyltin) oxide added (2.16 μg as TBTC) were more than 95% and about 3%, respectively.View full abstractDownload PDF (667K) -
Katsushige TAKAMI, Tameo OKUMURA, Akiyoshi SUGIMAE, Masao NAKAMOTO1987 Volume 36 Issue 3 Pages 143-148
Published: March 05, 1987
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSA gas chromatographic method is presented to determine traces of tricyclohexyltin compounds(TCTC) in environmental samples by using a clean-up cartridge packed with moderately sulfonated polystylene beads. The TCTC in water sample were converted to tricyclohexyltin chloride(TCTCl) with hydrochloric acid, and extracted with hexane. The extract was filtered, and the residue was washed with hydrochloric acid-ethanol solution. The TCTCl in the combined filtrates, mixed with water, was extracted with hexane and was concentrated to ca. 0.5 ml, then made up 10 ml with ethanol. The species in sediment were extracted with hydrochloric acid-ethanol solution and the extract was filtered. The filtrate, mixed with 15% of sodium chloride solution, was extracted with hexane. The organic phase was successively washed with 0.5 M sodium hydroxide in water-ethanol(1 : 1, v/v) and water was concentrated and made up in the same way as for the water sample. The TCTCl in the concentrated sample was passed through a cartridge packed with the hydrogen form resin, cleaned up with ethanol and eluted with hydrochloric acid-ethanol solution. TCTCl extracted with 5 ml volume of hexane was hydridized with 2.5% sodium borohydride-ethanol solution. The tricyclohexyltin hydride(TCTH) formed was extracted with hexane and analyzed by a gas chromatograph with 5% Silicone OV-1 column and electron capture detector(ECD). The TCTC in environmental samples were successfully cleaned up with the cartridge and determined by GC-ECD with good selectivity. Recoveries of the TCTC from water samples and sediments were 8697% with 1.45.0% of relative standard deviation, and the detection limit was 0.5 μg/l, 0.02μg/g as hydroxide, respectively.View full abstractDownload PDF (800K) -
Nobuyuki KASHIHIRA, Kazuo MAKINO, Kuwako KIRITA, Yoshichika WATANABE1987 Volume 36 Issue 3 Pages 149-153
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA simple and rapid method for the determination of acetaldehyde by GC was developed by employing a sorbent enrichment technique and a selective detection method. Gas chromatographic separation was performed on a Porapak Q packed glass column (3 mm i.d.×2 m) at 60 ml/min of N2 and 130 °C. The selective detection method is based on the flame ionization detector measurement of methane converted from acetaldehyde on reduced copper in hydrogen flow and it had the detection limit of 2 ng for acetaldehyde. Acetaldehyde of ng quantity in gas phase was preconcentrated quantitatively on alkalized Porasil A. The precision of the present method was 2.3% (n=7) as the relative standard deviation for air sample at 16 ppb. It was possible to determine acetaldehyde at few ppb level with one liter of sample gas. The effect of humidity in air was examined and its removal was discussed. The present method was applied to the determination of acetaldehyde in automobile exhaust gas and in suburban air, and 3.9 ppm and 3.7 ppb of acetaldehyde concentration as the mean values were obtained, respectively, without any interferences from other hydrocarbons.View full abstractDownload PDF (645K) -
Minoru FUKUSHIMA, Takeshi YAMAMOTO, Keiko MASUMOTO1987 Volume 36 Issue 3 Pages 154-158
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSOptimization of column parameters, namely the flow rate of carrier gas and temperature program rate for a determination of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) and 2, 3, 7, 8-tetrachlorodibenzofuran(TCDF) were performed using fused silica capillary column gas chromatograph connected with mass spectrometer. Using homologues of straight chain alkanes(C12C24), separation numbers (TZ value) were determined at eight different average linear velocity of carrier gas and temperature program rate of 4 °C/min. The experimental results elucidated the over view of a change of separation efficiency through the wide range of elution temperatures and flow velocity of carrier gas. It was suggested that flow velocity and column temperature should be controlled for the improvement of separation efficiency. The resolution (R) between closely eluting TCDD isomer (1, 4, 7, 8-TCDD) and 2, 3, 7, 8-TCDD was adopted as a parameter of separation. The average linear velocity of 40 cm/s was found optimum in case of using Supelco SP-2331 fused silica capillary column (60 m×0.32 mm i.d., 0.2 μm film thickness). The resolution of 2, 3, 7, 8-TCDD under the optimum flow velocity was examined at six different temperature program rate (1, 2, 3, 5, 7 and 10°C/min), and the temperature program rate of less than 3°C/min provides good resolution of the isomer at the separation of 6σ or larger. Under the optimized operation condition of GC/MS, relative standard deviation of determination for 2, 3, 7, 8-TCDD in sludge sample was 3.7%, and the detection limit was 0.02 ng/g dry wt.View full abstractDownload PDF (600K) -
Shigeru TANAKA, Kazuo YAMANAKA, Katsuhiro YAMAGATA, Yuichi KOMAZAKI, Y ...1987 Volume 36 Issue 3 Pages 159-163
Published: March 05, 1987
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSA method for the determination of sulfuric acid in the atmosphere by ion chromatography was investigated. Sulfuric acid in aerosols collected on a Teflon filter was extracted with benzaldehyde as a selective solvent for sulfuric acid, and then sulfuric acid in benzaldehyde was counterextracted with distilled water for ion chromatography. In the counterextraction, a portion of benzaldehyde dissolved in distilled water, and was rapidly oxidized to benzoic acid. The benzoic acid produced by oxidation of benzaldehyde seriously interfered with the determination of sulfuric acid by ion chromatography due to the overlapping peaks. Various methods such as the reduction with zinc powder, the extraction with benzene, and the cooling were tested for removal of benzoic acid. However, no sufficient removal by these methods was obtained. Instead of these methods, sulfuric and benzoic acids were separated by exclusion ion chromatography. Sulfuric acid was separated from benzoic acid by using ion exclusion column, and then the portion including sulfuric acid was reinjected to an ion chromatograph installed with the anion separator column for determination of sulfuric acid. The concentrations of sulfuricacid in the atmosphere at Hiyoshi, Yokohama from January to October, 1985 were 0.130.95 μg/m3. The detection limit of sulfuric acid by this method was 0.005 μg/m3 at sampling 4 m3 of air.View full abstractDownload PDF (638K) -
Shigeru TANAKA, Yuichi KOMAZAKI, Yoshihiro IKEUCHI, Yoshikazu HASHIMOT ...1987 Volume 36 Issue 3 Pages 164-168
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSSodium carbonate- and phosphoric acid-impregnated filters were tested for use in selective collection of SO2 and NH3 in the atmosphere. Collection efficiencies of SO2 and NH3 with these impregnated filters were measured by SO2 and NH3 standard gases at the levels below ppm. The collection efficiency of SO2, with Na2CO3 impregnated filter was higher than 96% at both high(80%) and low(10%) humidity, and the filter did not catch NH3. Therefore, it was concluded that the Na2CO3 impregnated filter had a good selectivity for SO2 and NH3 collection. Although the H3PO4-impregnated filter substantially collected SO2, especially at high humidity, it showed the sufficient collection efficiency for NH3. Air samples should be first passed through the Na2CO3-impregnated filter, then through the H3PO4-impregnated filter. Both Na2CO3-and H3PO4-impregnated filters collected SO2and NH3, were separately extracted with distilled water and subjected to ion chromatography. Sulfur dioxide being equivalent to the sulfite in the extracting solution was oxidized to sulfate with H2O2, and determined as sulfate. The detection limit in this method was 2 ppb for SO2 and NH3 when 0.3 m3 of air was sampled.View full abstractDownload PDF (697K) -
Tadao OKUTANI, Masanao TANAKA1987 Volume 36 Issue 3 Pages 169-173
Published: March 05, 1987
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSAn investigation for the determination of micro amounts of fluoride ion in water samples containing large amounts of sodium chloride or other ions was made by adopting the micro diffusion method with hexamethyl-disiloxane (HMDS) and ion chromatography. The proposed procedure is as follows. Five to sixty cubic centimeter of the sample solution is placed into an outer compartment (max volume 100 cm3) of a polyacrylic diffusion dish and 5 cm3 of a trapping solution (0.1 mol dm-3 sodium hydroxide solution) placed into an inner compartment. HMDS-saturated 2.7 mol dm-3 perchloric acid is added into a sample solution and then diffusion dish is covered with the lid. Generated trimethylfluorosilane is absorbed in a trapping solution by standing for overnight at room temperature. Fluoride ion is determined with ion chromatography after the sodium ion in a trapping solution was exchanged by ion exchange resin (HR). Chromatographic conditions are as follows: column; Shodex IC I-524A (100 mm×6 mm i.d.), eluent; 2.5 mniol dm-3 phthalic acid (pH 4.0, adjusted with TRIS), flow rate; 1.5 cm3/min, detection; conductivity, sample size; 0.1 cm3. A micro amounts of fluoride ion was concentrated twelve times by the proposed method. The detection limit was 4μg dm-3 for fluoride ion. The proposed method was applied to the determination of μg dm-3 level contained fluoride ion in seawater, tap water, well water and lake water.View full abstractDownload PDF (583K) -
Yasuyuki HOSHIKA, Ninzo MURAYAMA, Giichi MUTO1987 Volume 36 Issue 3 Pages 174-178
Published: March 05, 1987
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSThe ion chromatographic determination of trace amounts of lithium in river and drinking waters was investigated using a pressurized regenerant reservior and sample injector systems with pure nitrogen gas (>99.9%, about 3 psi). The conditions for the ion chromatography of the sample water were as follows : separator column, HPIC-CG 250 mm×4 mm i.d.+HPIC-CS2 250 mm×4 mm i.d., at room temperature; eluent, 8 mM HCl(1.6 ml/min); suppressor, cation fiber suppressor (CFS) system; regenerant, 0.02 M KOH (1.6 ml/min); detector, conductivity; sample volume, 50μl, respectively. The response (peak area, as the counts of a digital integrator of the conductivity detector) to the lithium was linear in the range of 23000 ppb. The minimum detectable concentration of lithium was about 1 ppb at S/N= 2. The analytical precision was 4.4% in the relative standard deviation. The detected concentration ranges of the lithium in river waters, was <0.536 ppb; and that in the drinking water was <0.555 ppb, respectively.View full abstractDownload PDF (483K) -
Mitsuhiro MATSUMOTO, Yoshitaka NISHIKAWA, Kentaro MURANO, Tsutomu FUKU ...1987 Volume 36 Issue 3 Pages 179-183
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSAn application of HPLC to the determination of aldehyde concentration in rain water was examined. It was found that the following procedures were suitable for rapid and simultaneous determination of five aldehydes {HCHO, CH3CHO, C2H5CHO, C3H7CHO(n- and iso-) and C2H5CHO}. First, a rain sample should be collected by a sampler into which 10 ml of 1000 ppm HgCl2 solution is added in advance. To 1 ml of the rain water sample, 200 μl of 1000 ppm 2, 4-dinitrophenylhydrazine (DNPH) and 20μl. of 5 N H3PO4 solutions are to be added and the mixture is allowed to react for 10 min to form DNPH derivatives of the aldehydes. Then, 50 of the sample solution is injected into a C18 column with an aqueous solution of CH3CN(H2O-CH3CN= 50 : 50, v/v). The present method gave HCHO concentration in agreement with that determined by a conventional method (AHMT method), and had definitely better sensitivity: the detection limit for HCHO was 0.002Mg/ml in contrast to 0.05μ, g/ml by the latter method. The reproducibility of the measurement was about 2.5% as expressed in terms of the relative standard deviation. The aldehydes in rainwater were stable for four months when the sample was spiked with HgCl2 or CHCl3. The method established in this study was applied to the analysis of rain water collected in Nara City in a period from June, 1985 to May, 1986. The annual mean concentrations of the aldehydes turned out to be as follows : 0.262 μg/ml for HCHO, 0.146 for CH3CHO, 0.021 for C2H5-CHO, 0.01 for C3H7CHO and 0.01 for C6H5CHO.View full abstractDownload PDF (685K) -
Yasuo SHIINA1987 Volume 36 Issue 3 Pages 184-188
Published: March 05, 1987
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSDetermination of atmospheric H2S should be accomplished within several hours after sampling because of its instability. A method for fixing H2S for 24 h or longer has beers expected. Since the addition compound. of S2- with HCHO showed excellent stability, other nonvolatile, water-miscible aldehydes such as glyoxal and glyoxylic acid, which were less volatile in field sampling, were tested to know the most stable adduct with S2-in buffered solution. Glyoxal adduct was the best in pH 4 buffer solution under the conditions described. In 24 h-aeration or 10 days storage in the dark place, more than 94% of S2- in the adduct was recovered. The compound split off S2- in alkaline solution and the ion was determined by a modified Methylene Blue method. Both concentrations of H2S fixed in the 3.7% glyoxal buffer solution and in 0.1 M NaOH solution (reference) were in good agreement with that of standard H2S gas used.View full abstractDownload PDF (761K) -
Preconcentration of Heteropolyacid-Malachite Green aggregatesChiyo MATSUBARA, Yasutaka YAMAMOTO, Gaku ODAKA, Kiyoko TAKAMURA1987 Volume 36 Issue 3 Pages 189-193
Published: March 05, 1987
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSA simple and rapid method for the determination of trace amounts of arsenate, arsenite and phosphate in sample water was proposed. Molybdophosphateand molybdoarsenate-Marachite Green aggregates formed by Mo-MG reagent(mixed solution of ammonium molybdate and Malachite Green) were selectively collected on a nitorocellulose membrane filter (3 μm pore size), and the aggregates were dissolved in a small volume of methylcellosolve together with the membrane filter. The absorbance (λ : 627 nm), denoted as A {P+As(V)}, was proportional to the sum of the concentrations of phosphoric and arsenic aggregates with molar absorptivity of 2.6×105 M-1 cm-1. Thiosulfate was added to the second portion of the sample water, as a reducing agent for arsenate to arsenite, and the absorbance of the solution, A(P), was measured in the same way as described above. A(P) corresponds to the concentration of phosphate alone. Iodate, an oxidizing agent for arsenite to arsenate, was added to the third portion of the sample water, and the absorbance of the solution, A{P+As(V)+As(III)}, was measured. The difference between A{P+As(V)} and A(P), and that between A{P+As(V) +As(III)} and A{P+As(V)} lead to the arsenate and arsenite concentrations, respectively. The present method makes it possible to determine arsenate, arsenite and phosphate as low as 0.3 ppb arsenic(III, V) and phosphorus.View full abstractDownload PDF (695K) -
Takashi KORENAGA, Etsu YAMADA, Yumiko HARA, Hayao SAKAMOTO, Tetsuji CH ...1987 Volume 36 Issue 3 Pages 194-198
Published: March 05, 1987
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSThe improved method is developed for the usual mecury determination by cold-vapor AAS with acidic tin(II) after digestion of the sample. In the Japanese official method, iodide and its related compounds interfered with the trace mercury determination. Hence, the improvement of the official method is necessary for complicated environmental samples such as waste waters from university laboratories. The determination procedures are as follows: An aliquot (less than 100 ml) of sample solution is taken into a reaction vessel after digestion with potassium peroxodisulfate in a diluted sulfuric acid solution heated at 95 °C for 1 h. To the solution, 10 ml of 5 M sodium hydroxide, 2 ml of 1000 mg/l Cu2+ solution, 10 ml of 5% potassium zinc cyanide solution, and 2 ml of 10% tin(II) chloride solution are added, and the evolved mercury is measured with an atomic absorption spectrometer at 253.7 nm. The reducing power of tin(II) in alkaline solution is stronger than that in acidic solution because the standard redox potential for tin(II) is -0.93V vs. NHE at pH 14 (0.15V vs. NHE in acidic). However, potassium zinc cyanide is added as a masking agent for silver(I) ion because it interferes with the improved alkaline method. The detection limit and precision of the improved method are 0.5μg/l and 3%, respectively. The method was applied to the determination of mercury in waste water samples containing iodide with satisfactory results.View full abstractDownload PDF (772K) -
Shiro GOHDA, Hideo YAMAZAKI, Masaru HIRATA, Taro NAGASAWA1987 Volume 36 Issue 3 Pages 199-203
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA simple and rapid method is described for the determination of major and trace elements in rock and sediment samples by wavelength dispersive XRF. Sample measured were made from cellulose powder pressed into 4 cm diameter aluminium ring 0.4 t cm-2, and then 1 g of powdered sample (0.08 g cm-2) was placed on the disk and repressed at 1.6 t cm-2. X-ray measurements were performed for total XRF intensity (Ip) at the characteristic line of each element and background intensity (Ib) in vicinity of the line. The correction of matrix effect was achieved by X-ray intensity ratio of peak to background for each element. Eight standard rock samples from Geological Survey of Japan were used as standard materials, and linear calibration curves were obtained by the plot of Ip-Ib vs. concentration for Ca, Na and Pb and by the plot of Ip/Ib ratio vs. concentration for Si, Fe, Ti, K, P, Cl, Cr, Mn, Ni, Cu, Zn, Pb, Sr and Ba, respectively. The relative standard deviation was estimated to be about 3% for 15 elements and 67% for Ba and Pb in river and marine sediment samples. The proposed method was applied to the determination of 17 elements in Pond Sediment (NIES No. 2) and Estuarine Sediment (NBS SRM 1646), and the results were in good agreement with the recommended values.View full abstractDownload PDF (726K) -
Minori KAMAYA, Tetsuro MURAKAMI1987 Volume 36 Issue 3 Pages 204-207
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSSensitive spectrophotometric method for the determination of nitrite ion with p-aminoazobenzene was investigated: A 5 ml of p-aminoazobenzene in acetic acid-methylcellosolve medium was added to 510 ml of aqueous solution of 212 μg of nitrite ion and the mixture was allowed to stand for 60 min at about 25 °C. The resulting solution was made alkaline by adding 5 ml of 2 M NaOH and diluted to 25 ml with methylcellosolve. The absorbance at 570 nm was measured against blank solution. Beer's law holds and the present method showed good reproducibility of relative standard deviation 1.2%, and the molar absorptivity was 6.90×104 lmol-1 cm-1. Copper(II), tin(II) and sulfite, thiosulfate ion interfered with the determination of the analyte. The present method was applied for the determination of nitrite ion and nitrate ion in rainwater, and the results showed good agreement with those obtained with JIS method.View full abstractDownload PDF (423K) -
CHENG RUI Shi, Shoji MOTOMIZU, Kyoji TÔEI1987 Volume 36 Issue 3 Pages 207-209
Published: March 05, 1987
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSN, N-Bis (2-hydroxypropyl) aniline (BHPA) reacts with nitrite ion in an acidic medium to form a red product, which has the maximum absorption at 500 nm. On the basis of this color reaction, FIA of nitrate was established. Nitrate ion could be reduced to nitrite ion by passing through the reduction column(2 mm×30 cm) packed with copperized cadmium {Cu(Cd) : particle size, about 0.5 mm}, which was installed just behind the sample injection valve. The carrier solution(10-3 M EDTA, pH 8) and the reagent solution (8×10-4 M BHPA, 0.35 M HCl, 0.15 M H3PO4) were propelled at the flow rate of 0.7 ml/min by using a double-plunger pump. The sample(120 μl) was injected into the carrier stream by using a 6-way injection valve. The reaction coil(0.5 mm×2 m) was kept in a thermostatically controlled water bath(80 °C). The cooling coil(0.5 mm × 50 cm), which was installed just behind the reaction coil, was kept in a water bath (tap water temperature). A calibration curve was linear up to 2×10-4 M nitrate. The detection limit corresponding to S/N=2 was 10-6 M nitrate, and the relative standard deviation (10 injections) was 0.4%, and the sampling rate was 40 samples per hour. Nitrate in river water at concentrations of 10-5 M level was determined.View full abstractDownload PDF (352K) -
Tadao SAKAI, Noriko OHNO, Takeshi KAMOTO, Nobuo ICHINOBE, Hideto SASAK ...1987 Volume 36 Issue 3 Pages 210-213
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSSensitive and selective spectrophotometric methods are proposed for the determination of chlorhexidine, benzethonium and benzalkonium, which are useful and popular disinfectants in the hospital, by solvent extraction based on ion pair formation. Chlorhexidine reacted with tetrabromophenolphthalein ethyl ester (TBPE) to form a 1 : 2 red violet ion associate (λmax=570 nm) and its molar absorptivity was 6.77×104l mol-1 cm-1. The determination limit was 0.058 μg/ml. This method was more sensitive than other associates with TBPE and applied for the determination of trace amounts of chlorhexidine in the hospital disinfectant waste water. Benzethonium and benzalkonium(bulky quaternary ammonium disinfectants) were selectively determined by extraction based on ternary ion pair formation among quinine, Bromophenol Blue and quaternary ammonium ions. Optimum pH range was 6.57.1. The molar absorptivity of benzethonium as sociate was 5.04×104l mol-1 cm-1 and that of benzalkonium was 4.85×104 l mol -1cm-1 and relative standard deviations were about 1.5%. λmax was at 610 nm. This method is also available for the determination of quaternary ammonium disinfectants in waste water.View full abstractDownload PDF (728K) -
Shizuko HIRATA, Kazuto HONDA1987 Volume 36 Issue 3 Pages 213-216
Published: March 05, 1987
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSAtomic absorption spectrometry with on-line chelating-resin column preconcentration has been applied to rapid determination of zinc in seawater. Filtered coastal seawater samples adjusted to pH 2.2 by adding 1 ml of conc. nitric acid against to 1 l of seawater was pumped at 6.0 ml min-1 and mixed with a stream of ammonium acetate buffer (pH 7) at 0.5 ml min-1. The sample was then passed through a microcolumn (3.2 mm i.d. 16 mm long) packed with Chelex-100 for 1 min. The column was washed with distilled water for 30 s and sequentially chelated zinc was eluted with about 160 μl of 2 M nitric acid at 3.0 ml min-1 for AAS determination. This method gave enhanced sensitivityof zinc by over 19 times better than that of a conventional AAS. The detection limit of the present method was 0.5 ppb (S/N=2). Precision of this method was 2.7% (R.S.D.) at the 10 ppb level of zinc aqueous standard. About 30 samples could be analyzed for 1 h. The present method was successfully applied to the rapid determination of zinc in seawater of Beppu Bay.View full abstractDownload PDF (681K) -
Tadao OKUTANI, Akira NAGANUMA1987 Volume 36 Issue 3 Pages 216-219
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe selective adsorption of metal ions with activated carbon(AC) and potassium ο-ethyl dithiocarbonate (potassium Xanthogenate) was studied for the preconcentration of traces of Cd(II), Pb(II), Cu(II) and Co(II) ions. To the sample solution of about 100 cm3, 120 mg of potassium Xanthogenate and 50 mg of AC were added, and the mixture was stirred for 20 min in a ultrasonication bath and filtered. AC was heated with 1 cm3 of concentrated nitric acid. After nitric acid was evaporated, adsorpted metals were desorbed in the bath using 5 cm3 of 3 mol dm-3 nitric acid and the AC was removed by filtration. The concentrations of the metal ions in the solution were measured by AAS. The proposed method was successfully applied to the determination of the trace metals in bottom sediments such as pond(NIES, No. 2), river and marine environment by AAS. The results obtained for pond sediment were in excellent agreement with certified values. This method is very simple, and suitable for the determination of trace amounts of Cd, Cu, Pb and Co in the sample containing large amounts of Fe and Al.View full abstractDownload PDF (676K) -
Masataka HIRAIDE, Feng-Lian REN, Atsushi MIZUIKE1987 Volume 36 Issue 3 Pages 219-221
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSTo 1 liter of water containing humic acid was added 1 ml of iron(III) solution (10 mg Fe/ml) and the pH was adjusted to 7 to collect the humic acid on iron(III) hydroxide precipitates. Three ml of 70% ethanol solution of sodium oleate (0.2 mg/ml) and sodium dodecyl sulfate (0.6 mg/ml) was added to render the precipitate surfaces hydrophobic. The precipitates were rapidly floated with numerous nitrogen bubbles (0.10.5 mmin diam.), collected and then dissolved in 10 ml of 2 M hydrochloric acid. Humic acid was filtered off on an ultrafilter (molecular weight cut-off, 10000) and ultrasonically dissolved in 10 ml of 0.1 M potassium hydroxide solution for the spectrophotometric determination. Within 1 h of the entire procedure, 0.015 mg/l of humic acid was recovered at more than 92%.View full abstractDownload PDF (326K) -
Daisuke KURODA1987 Volume 36 Issue 3 Pages T21-T24
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSRound robin tests were carried out for the investigation about the precision of charcoal tube samplers for determination of organic vapours in the industrial atomosphere. Eight artificial gas samples contained two or three constituents of organic solvent vapour were used. Charcoal tube samplers collected these gases were distributed to 2025 laboratories and the results were compared with respect to mean values, relative standard deviation and accuracy. The satisfied results were obtained for the storage and the recovery of samples with the charcoal tube samplers.View full abstractDownload PDF (564K) -
Tohru SAKAI, Toshikatsu IRIYE1987 Volume 36 Issue 3 Pages T25-T28
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSAfter thawing the frozen biological materials, pretreatment for the determination of cyanide in biological materials were carried out by aeration method at pH 5.5 and distillation method at pH 5.0 for free cyanide and distillation method at pH 2.0 for total cyanide based on the determination of cyanide in water defined by JIS K 0102. The conditions for sample treatment were examined thoroughly and established as follows; 1) Fish samples : The aeration time in aeration method was required 12 h at 50 °C. The primary distillate volume was required about 140 ml in distillation method at pH 2. 2) Aquatic plant: The aeration time in aeration method was required 24 h. The primary distillate volume for distillation method at pH 2 was required about 190 ml. 3) Algae sample: The primary distillate volume was required about 190 ml in dlistillation method at pH 5.5 and about 140 ml in distillation method at pH 2 respectively. Although the analytical results for free cyanide were not reproducible enough. The recovery of total cyanide gave sufficient results.View full abstractDownload PDF (634K) -
Taeko DOI, Keiko SHIBATA, Masayuki KUNUGI, Tsuguo MIZOGUCHI1987 Volume 36 Issue 3 Pages T29-T34
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThis paper describes a method of measuring trace metals in particulate air pollutants by energy dispersive XRF spectrometry and analysis of measured data. Samples were collected on the filters with three types of low-volume air samplers. Samples collected with a settling type and a cyclone type sampler were not uniform on the filter. Samples collected with a dichotomous sampler were uniform on it. In winter, high concentrations of fine particles containing Pb, Zn, Cu, V and Br had been observed. In spring, high concentrations of coarse particles had been determined because of yellow sand phenomena.View full abstractDownload PDF (700K) -
Hidehiko WAKUDA, Masatoshi ICHIKAWA, Ichiro TAKADA1987 Volume 36 Issue 3 Pages T35-T40
Published: March 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThis report describes a personal computer system for the analysis of data collected regarding hazardous substances in the air of the working environment. A predetermined sampling method was applied to the collection of GC data. The computer received the data through an A/D converter and calculated the environmental levels. Then, the safety level of the working environments were assessed by referring to the predetermined criteria. By using this system, it becomes possible to reduce the time spent on complicated calculations and control the safetyof the working environment more efficiently.View full abstractDownload PDF (631K)
- |<
- <
- 1
- >
- >|