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Volume 25, Issue 8
Displaying 1-16 of 16 articles from this issue
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Gel chromatography of β-diketones and their metal complexes. VKoichi SAITOH, Nobuo SUZUKI1976 Volume 25 Issue 8 Pages 491-496
Published: August 10, 1976
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe distribution coefficients, Kav, of acetylacetone, HAA, were measured with high precision. The Kav values depend much on the solvents as eluents. In each solvent system, Kav value of HAA is different from that of a hypothetical n-alkane with the same molar volume. The ratio of these two coefficients, R, depends on the solvents. Relationship between R and molar solvent regain of gel, Srm, which is a variable referring to the degree of solvent-gel interaction, reveals that the smaller the solvent-gel interaction the more HAA-gel interaction participates. Comparing Kav values of HAA with those of its beryllium(II) and chromium(III) chelates, the sieving effect on the elution behavior of these compounds has been confirmed. Gel chromatographic behavior of HAA in each column system is governed not only by the sieving effect but also by an interaction between solute and gel.View full abstractDownload PDF (1040K) -
Yoshifumi AKAMA, Toshio NAKAI, Fumikazu KAWAMURA1976 Volume 25 Issue 8 Pages 496-500
Published: August 10, 1976
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESS4-Benzoyl-3-methyl-1-phenyl-5-pyrazolone (BMPP) was prepared by the method of Jensen, and employed for the extraction of lead. Micro amounts of lead were extracted from aqueous solution of pH 6.59.0 into MIBK as BMPP-complexes and determined by atomic absorption spectrophotometry. Formation of a 1:2 complex of lead with BMPP was confirmed by the continuous variation method. The presence of 2 mg of Al(III), Cu(II), Co(II), Mn(II), Ni(II), Zn(II), and V(V) interfered with the determination of lead. The proposed procedure for the determination of micro amount of lead in commercial carbonated drinks is as follows: to an aliquot of carbonated drinks in a separation funnel, add 10 ml of 10 w/v% diammonium hydrogen citrate and 10 ml of 40 w/v% ammonium sulfate, adjust the pH to 7.07.5 with aqueous ammonia, and then extract the lead into a 10 ml potion of 0.3 w/v% BMPP-MIBK solution. The lead in the organic phase is determined by atomic absorption spectrophotometry using the standard addition method. The sensitivity and the coefficient of variation were 0.05 ppm/1% absorption and 2.7% for 0.052 mg Pb/1000 ml, respectively.View full abstractDownload PDF (743K) -
Kenyu KINA, Katsuhiko SHIRAISHI, Nobuhiko ISHIBASHI1976 Volume 25 Issue 8 Pages 501-505
Published: August 10, 1976
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA new lumogallion-analogue containing hexyl group as a long alkyl chain has been synthesized. The hexyl-lumogallion (Hexyl. LUMO) formed a fluorescent one to one chelate complex with gallium(III) in the optimum pH range of 2.7 to 4.0. The Ga(III)-Hexyl·LUMO complex was easily extracted into methyl isobutyl ketone (MIBK). The complex had its maximum emission at 580 nm with an excitation at 493 nm. The fluorescence intensity of the complex in the extract was 25 times stronger than that in aqueous solution when equal volumes of MIBK and the aqueous solution were used.
The concentration of ppb level of gallium was able to be easily determined. The quenching effect of the transition metal was markedly reduced by the MIBK extraction method.
The fluorescence intensity of the chelate complex was sensitized with nonionic or anionic surfactant micelle. The nonionic surfactant was more useful for the sensitivity enhancement of the fluorometric analysis of gallium. It was confirmed that the fluorescence quantum efficiency of the complex increased about 10-fold in the presence of polyethylene glycol monolauryl ether, a nonionic surfactant. The fluorescence polarization spectra suggested that the presence of the hexyl group caused a strong binding of the complex to micelle.View full abstractDownload PDF (858K) -
Shigeki OHNISHI, Yasushi NISHIJIMA, Kyoko SUGIYAMA1976 Volume 25 Issue 8 Pages 506-509
Published: August 10, 1976
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSTrace amounts of imidazole-4(5)-acrylic acid (urocanic acid) in the human epidermis were determined by high speed liquid chromatography using a polyvinylacetate porous polymer (TSK GEL LS-140) as a column packing. Eluent composition, column temperature and flow rate were investigated in correlation with HETP, and the following conditions were established; eluent=0.75% triethylamine in methanol; column temperature=20°C; flow rate=0.5 ml/min. The column effluent was monitored at 277 nm which was a maximum absorption wavelength of urocanic acid in eluent. The limit of detection was 5 ng. Employing this analytical method, the extractive conditions (solvent and extraction time) of urocanic acid from the human epidermis were also examined. The urocanic acid in the human epidermis was extracted. within about 10 seconds with water. The peak component was identified by ultra violet absorption spectra and mass spectrometry with that of urocanic acid. The urocanic acid contents measured by this method in the human epidermis of forearm were (0.214.85)μg/ cm2.View full abstractDownload PDF (615K) -
Yoshinori KIDANI, Kouji NAKAMURA, Kenji INAGAKI1976 Volume 25 Issue 8 Pages 509-513
Published: August 10, 1976
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESS2-Amino-4-hydroxypteridine-6-carboxylic acid, one of the oxidation products of folic acid with potassium permanganate, reacts with nickel ions to form a metal complex. The nickel complex is extracted with methyl isobutyl ketone (MIBK) in the presence of bathophenanthroline. Therefore, quantitative determination of folic acid can be made indirectly by measuring nickel content in MIBK phase by atomic absorption spectrophotometry.
In this experiment, a Hitachi 207 atomic absorption spectrophotometer, was used, and the analytical line at 2320 Å was used for the measurement of nickel with air-acetylene flame.
The procedure is as follows : To proper amounts of folic acid in a 0.01 N NaOH solution, is added 5 ml of 4% potassium permanganate, and the solution is allowed to stand for 10 minutes at room temperature. In order to remove excess amounts of potassium permanganate, hydrogen peroxide is added, and the solution is filtered off. The filtrate is diluted to 100 ml in a volumetric flask with deionized water. One milliliter of the above solution, 4 ml of an aqueous solution of 1.0×10-3 M nickel sulfate, and 5 ml of 1.0×10-2 M borate-H2SO4 buffer solution at pH 8.5, are mixed in a 50 ml centrifuge tube. The mixed solution is shaken well with 10 ml of MIBK in the presence of bathophenanthroline for 25 minutes. It is allowed to stand for 10 minutes. To one ml of the MIBK extract separated is added 7 ml of MIBK, and the quantity of nickel is measured by an atomic absorption spectrophotometer.
The required molarity of nickel sulfate and bathophenanthroline is more than 6.6 and 44 times that of folic acid, respectively.
Under these conditions, absorbance of nickel concentration in MIBK phase shows a linear relationship over the range of (1.220.0) μg/ml of folic acid. No interference was observed of the coexisting compounds, such as nicotinamide, pyridoxal phosphate, calcium pantothenate, thiamine, cyanocobalamine, retinol acetate, and riboflavine, except ascorbic acid. It interfered permanganate oxidation of folic acid. The relative standard deviation of this method is 1.76%.View full abstractDownload PDF (725K) -
Yoshinori KIDANI, Shizuo UNO, Kenji INAGAKI1976 Volume 25 Issue 8 Pages 514-518
Published: August 10, 1976
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSAmino acids react with salicylaldehyde to yield their Schiff's bases in alkaline solution, and the Schiff's bases-Cu(II) chelates formed by the addition of Cu(II) ion are extractable with MIBK in the presence of bathophenanthroline. Therefore, amino acids can be determined indirectly by the estimation of copper in the organic phase by atomic absorption spectrophotometry. Two ml of (2.0×10-52.0×10-4) M amino acid solution, 2.0 ml of 1.0×10-2 M salicylaldehyde solution, 1.0 ml of 1.0×10-3 M cupric acetate solution and 5 ml of boric acid buffer solution of pH 10.0 were taken into a 30 ml centrifuge tube and mixed sufficiently. After the solution was allowed to stand for 5 minutes, 10.0 ml of chloroform was added. The mixture was shaken for 10 minutes and was centrifuged. After separation, 5.0 ml of the upper aqueous phase was transferred into another 30 ml centrifuge tube and 10.0 ml of 1.0×10-4 M bathophenanthroline MIBK solution was added. Being shaken well for 5 minutes, it was centrifuged and the copper in organic phase was determined by atomic absorption spectrophotometry.
The optimum pH range was found to be 9.511.5. On the determination of glycine, the linear relationship was found between the absorbance and the concentration in the range of (1.515.0) μg/ml and the standard deviation and the coefficient of the variation were 0.71 and 1.45% respectively and the recovery was 99.8%. This method is applicable to the quantitative determination of amino acids such as glycine, valine, phenylalanine, tyrosine, tryptphan and methionine.View full abstractDownload PDF (654K) -
Hideko KISHI, Kikuo OIKAWA, Yoshikazu HASHIMOTO1976 Volume 25 Issue 8 Pages 519-524
Published: August 10, 1976
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA method was investigated to seek the optimum irradiation-, cooling-, and counting time for economy of time, labor, and cost. For the first step, the terms of the basic equation of induction and decay of radioactivity were grouped into three parts: the terms of time, of proper values to each nuclide, and of variables due to experimental conditions. Then the equation was simplified by taking logarithm, and the values caluculated from the equation for the terms of time and the characteristic values of each nuclide were tabulated. The counting time was decided in such a way that the counts of radioactivity of each nuclide fall in a range between minimal and maximal counts which were decided by counting statistics and by the dead time level of the measuring instruments. The calculation was made by simple treatment of the variables of the experimental conditions and of the values found in the prepared tables. An experimental scheme designed by the above method was applied to analysis of an atmospheric “standard” reference sample, and the analytical results were compared with those by the experimental scheme by R. Dams and with those obtained by three nuclear laboratories. The comparison showed that the present method made experiments economical in time, labor, and cost of the analysis by shortening the time of measurement to one half of those of R. Dams, leaving the accuracy almost in the same level.View full abstractDownload PDF (962K) -
Kikuo OIKAWA, Toshio NOMURA, Hiromu MARUYAMA1976 Volume 25 Issue 8 Pages 524-528
Published: August 10, 1976
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSIt is important to know the crystal form of atmospheric particles for studying the effect of metals on biological environment as well as for clarifying the mechanism of air pollution including photochemical smog and acid mist.
The authors devised the following method for determining α-ferric oxide (α-Fe2O3) and triiron tetraoxide (Fe3O4) which are supposed to work as an oxidizing catalyst and thus contribute to the occurrence of sulfuric mist.
Weigh α-ferric oxide and triiron tetraoxide as standard samples for calibration, so that they may represent 2, 5 or 8 wt%, in glass powder diluent, respectively. Put each standard sample on the plate of a rotating sample board and add rutile titanium dioxide (TiO2) as an internal standard. Put a nitrocellulose membrane filter and add acetone drop by drop. Mix quickly and dry it to mold a filter-type sample for X-ray diffraction analysis. The calibrations curve were obtained by measuring the integrated intensity ratios of reflection, Iα-Fe2O3/ITiO2, IFe3O4/ITiO2.
Atmospheric particles were collected on a nitrocellulose membrane filter using a low volume air sampler and treated in the same manner as the standard samples.
The variation coefficient of the analytical data of α-ferric oxide and triiron tetraoxide obtained by the present method was approximately 10%. The detection limit was 0.7 wt % for the former and 0.5 wt for the latter.View full abstractDownload PDF (805K) -
Yasuyuki HOSHIKA, Yoshinori TAKATA1976 Volume 25 Issue 8 Pages 529-533
Published: August 10, 1976
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA complete gas chromatographic separation of benzaldehyde, ο-, m- and p-tolualdehydes was succeeded by using a glass capillary column. The gas chromatographic conditions were as follows: stationary phase, PEG-20 M; column size, 0.25mm i.d.×30m; column temperature, 100°C; carrier gas flow rate, nitrogen 1.3 ml/min. n-Butyl amine was added to the solution of these aldehydes to form Schiff base and the solutions were allowed to stand for two hrs. at 25°C. Then the produced Schiff bases were analysed with a glass capillary column by using n-heptadecane as an internal standard. Benzaldehyde, ο-, m- and p-tolualdehydes in free aldehydes and the corresponding Schiff bases were separated clearly in about 20 minutes. The present method was applied to analyse benzaldehyde, ο-, m- and p-tolualdehydes in the exhaust gas of automobiles. The procedure for the collection of a sample gas and preparation of these Schiff bases with n-butyl amine were as follows: the exhaust gas (30 l) was collected by cold trap with liquid oxygen and ethyl alcohol (5 ml) was added to the condensate. The solution was concentrated under vacuum to 0.2 ml and n-butyl amine (5μl) was added. The minimum detectable quantities of the four aromatic aldehydes and their corresponding Schiff bases were in the order of 0.01μg.View full abstractDownload PDF (825K) -
Sadanobu INOUE, Takao YOTSUYANAGI, Mitsuo SASAKI, Kazuo AOMURA1976 Volume 25 Issue 8 Pages 534-539
Published: August 10, 1976
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSDimercaptomaleonitrile (maleonitriledithiol, H2 mnt or H2L) reacts with cobalt to form a water soluble stable complex, CoL33-, at pH 4.5 to 11.4, which has an absorption maximum at 288 nm with a molar absorptivity of 5.59×104 l/mol cm. The charge of the complex was estimated to be 3- by extracting the complex into chloroform with tetra-n-hexylammonium iodide (tha+I-) as an ion association complex, (3tha+, CoL33-). Although the free ligand is easily oxidized in air, zinc(II) ion stabilizes it by forming, at pH 2.2 to 9.5, water soluble stable complex, ZnL22-, which reacts with cobalt to give CoL33- complex quantitatively. The difference of the absorptivity between CoL33- and ZnL22- at 288 nm (Δε288nm=5.0×104l/mol cm) is large enough to make possible the spectrophotometric determination of cobalt. Under the condition of the recommened procedure, the metal exchange reaction proceeded quantitatively within 2 minutes and absorbance was effectively constant for 45 minutes. Beer's law was confirmed in a range of 022 μg Co2+/ 25 ml and the sensitivity for absorbance=0.001 was 1.2×10-3 μg Co2+/cm2. Among 15 metal ions studied, nickel, iron and copper seriously interfered with the determination. However, nickel and cobalt can be determined simultaneously based on the difference in absorption spectra of their mnt complexes.
Our recommended procedure is as follows; take the sample solution containing less than 22 μg of cobalt(II) in a 25 ml volumetric flask. Add 5 ml of 7.5×10-4 M ZnL22- solution and 0.1 M hexamine-HCl buffer (pH 5.1) and dilute to the mark with water. Measure the absorbance at 288 nm (in the presence of nickel, also at 312 nm) against the reagent blank within 45 minutes.View full abstractDownload PDF (1014K) -
Shigeru SHIMOMURA, Hideyoshi MORITA, Masanori KUBO1976 Volume 25 Issue 8 Pages 539-543
Published: August 10, 1976
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSOptimum analytical conditions in the determination of beryllium was investigated with a flameless atomic absorption spectrometry using a graphite tube atomizer. Large amounts of BaCl2, SrCl2, CaCl2 and MgCl2 suppress the atomic absorption signal of beryllium and these suppressions were influenced by temperature and time in ashing stage. However, this interference was completely removed by the addition of a small amount of sulfuric acid or nitric acid. Sulfates and nitrates of Ba, Sr, Ca, Mg did not interfere. Suppression of the absorption signal was observed in the presence of Al of low concentration, whereas enhancement of the signal was observed in the presence of high concentration of this element, even if the background was corrected. The coexistence of ferric salts suppressed the absorption signal too, but this interference could not be solved by such modifications as ashing condition or addition of acids. Interference of H2SO4 in high concentration was almost avoided by raising the ashing temperature as slowly as possible. In the presence of carboxylic acid or phosphoric acid, a tendency was shown that the sensitivity and precision decreased owing to nonuniformity of sample solution in a graphite tube at drying stage. In oder to prevent this problem, it is desirable to use a smaller sample size.
In this method, the absolute sensitivity was 1×10-12 g of beryllium per 1% absorbance.View full abstractDownload PDF (842K) -
Sanae IKEDA, Hiromu SATAKE1976 Volume 25 Issue 8 Pages 544-548
Published: August 10, 1976
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA potentiometric titration of thiosulfate with silver ions was studied by using a silver ion selective electrode. The recommended procedure is as follows:
(1) Standardization of sodium thiosulfate solution Titrate 100 ml of (0.00050.005) M thiosulfate solution (pH 1.510.5) with 0.1 M silver nitrate solution at room temperature above 20°C.
The relative error was +0.2% and the coefficient of variation was less than 0.2% when the titration was carried out in (1020) minutes.
(2) Determination of sodium thiosulfate in sodium sulfite
Titrate 100 ml of (0.000050.0005) M thiosulfate solution containing large amounts of sulfite with (0.010.1) M silver nitrate solution. Before titration, adjust the solution pH to 1.52.0 with dilute sulfuric acid and the solution temperature at about 60°C.
A small amount of sodium thiosulfate (e.g. 0.025%) was determined with the relative error of +0.6% and the coefficient of variation of 0.3% when the titration was performed slowly in 50 minutes.
This titration method is simple and precise and especially suitable for the assay of a mixture of thiosulfate and sulfite.View full abstractDownload PDF (811K) -
Sakingo IMAI, Shiro FURUYA, Yuzuru KUSAKA, Haruo TSUJI1976 Volume 25 Issue 8 Pages 549-551
Published: August 10, 1976
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSBy using commercially available reagents for standard and buffer agent, the analytical method for airborne particulates collected on membrane filter, which was previously reported in this journal 22, 551(1973), was improved to a simple and rapid one.
The decolorized ash of the sample obtained by ignition in a plasma asher was mixed with 50 mg of indium oxide as a buffer agent, which was selected from the basis of the results of the I-T experiments as shown in Fig. 1.
The standard series were prepared by diluting the Spex Mix No. 1000, containing 49 elements of each 1.27%, with indium oxide to give a concentration of 1.00% to 0.2 ppm for each element.
Then, the analytical and the standard series samples were mixed with equal amounts of graphite powder containing 50 ppm palladium as an internal standard.These samples were subjected to the AC are excitation in a similar way to the previous report. The use of a cup-typed graphite electrode with a sample hole of 3 mm×3 mm depth and the application of the following lines in the calibration curve were newly introduced: Ga; 2874.2Å, Sn; 2840.4Å, Mn; 2794.8Å, Fe; 2585.9Å, Al; 2568.OÅ.
Linear relationships were obtained in the following concentration ranges : Al; (5001000) ppm, Fe; (200500) ppm, Ti and Ga; (50500) ppm, Ni and Cr; (101000) ppm, Pb; (10200) ppm, Cu; (55000) ppm, Mn; (5100) ppm, V; (1500) ppm, Mo; (2500) ppm, and Ag; (0.250) ppm.
The analytical results and the precision for the 14 elements in a dust sample are shown in Table 1.
With this method, it was possible to treat 30 airborne particulate samples within 6 days. The application of this method for the Kobe area samples was reported in Journal of Japan Society of Air Pollution, 9, 742 (1975).View full abstractDownload PDF (571K) -
Determination of percent extraction of zephiramine for several organic solvents by colloid titrationMichio ZENKI1976 Volume 25 Issue 8 Pages 552-554
Published: August 10, 1976
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSColloid titration is one of the method of determining polyelectrolytes, by which the percent extraction of zephiramine (tetradecyldimethylbenzylammonium chloride) can be easily determined.
A negatively charged colloid solution, PVSK (potassium polyvinylsulfate) was used as titrant, and toluidine blue as indicator. The mixture of 10 ml of zephiramine solution and 10 ml of an organic solvent was shaken for 30 minutes in a 30 ml stoppered test tube. After shaking, the mixture was allowed to stand for one hour. Five ml of the aqueous phase was taken into an Erlenmeyer flask, and titrated with N/400 PVSK solution. The end point was reached when the color changed from blue to red-violet. Benzene, toluene, 1, 2-dichloroethane, chloroform, carbone tetrachloride and dimethylisobutyl ketone were examined as the organic solvent. Chloroform is the most favorable solvent for the extraction of zephiramine (above 90%). The values of the percent extraction of zephiramine in water-saturated and -unsaturated solvents indicate that a small amount of water contained in the organic solvent gives no effect on the extraction behavior. This method is also applicable to the mixed solvent, for example chloroform and carbone tetrachloride.View full abstractDownload PDF (455K) -
Naoshige AKIMOTO, Keiichiro HOZUMI1976 Volume 25 Issue 8 Pages 554-557
Published: August 10, 1976
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSDynamic responses of ion selective glass electrodes have been studied when they are subjected to sudden change of cation concentrations. Ion selective glass electrodes used were Orion 94-11A and an electrode of domestic product either having the same glass composition as Corning NAS 11-18 which is so-called sodium selective electrode, Corning NAS 27-4 characterized by its high selectivity to K+ and Corning 476024, a conventional pH glass electrode. The experimental method is the same as described in the previous paper.
Both the Orion 94-11A and the domestic product indicated similar characteristic patterns of the transient responses to K+ and Ba2+ as in the case of Corning NAS 11-18, that is, the electrodes rapidly developed overshoot potentials which were then restored towards their equilibrium levels. Orion 94-11A, however, restored the transient response somewhat faster than in the case of Corning NAS 11-18. The Domestic one exhibited much larger potential change than the other electrodes and was considerably responsive to K+ as the steady-state potential, although initial transient response almost disappeared with time in the case of Ba2+. The electrode potential of Corning NAS 27-4 moved towards one side direction for K+ and Ba2+ without development of the transient potential. Corning 476024 also developed the transient response to Na+ in the background solution of 0.01 M diisopropylamine (pH 11.5), but it disappeared quickly within a short period.View full abstractDownload PDF (566K) -
Hiroshi NAKAGAWA, Fumiaki MUNEYOSHI, Machiko KOSAKO, Kaoru OZASA1976 Volume 25 Issue 8 Pages 558-559
Published: August 10, 1976
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIt has been considered very difficult to make a quantitative analysis by extracting chromium(VI) {Cr(VI)} throughly, because sludge contains slightly soluble chromates together with organic substances or reducible materials.
The method proposed here is just to solve the above mentioned problem and charactarized by the following process (i) and (ii).
(i) Dissolve slightly soluble chromates by treating the sample with EDTA in an ammoniacal alkaline medium, and then excess EDTA is masked with calcium. As excess EDTA impedes the formation of Cr(III)- DDTC, the EDTA must be masked by adding calcium to the sample slurry prior to neutralization.
(ii) Allow to react the dissolved Cr(VI) with sodium diethyldithiocarbamate(DDTC) at pH 57, and then extract the formed Cr(III)-DDTC into methylisobutylketone(MIBK) immediately. It is necessary for DDTC and MIBK to be made to co-exist with the sample slurry in order to proceed with this process(ii) more effectively.
Procedure: Transfer the finely pulverized sample, containing (5200) μg as Cr(VI), to separating funnel in which 20 ml of 10% DDTC solution is contained. Add 20 ml of 0.05 M EDTA solution and 10 ml of concentrate ammonia water, and then shake it for ten minutes. Add 25 ml of 0.05 M calcium chloride solution and mix. Adjust the pH of the mixture to 5 by adding acetic acid-ammonium acetate buffer solution. Shake the mixture for a few minutes with (50100) ml MIBK. Filter the residue on a small filter paper and then allow the phases to separate. Finally evaporate the solvent after separating this organic layer, and decompose the residue with nitric acid. The solution obtained thereby is to be analyzed by atomic absorption spectrometry.
This method is applicable to practical use of Cr(VI) in environmental matters.View full abstractDownload PDF (264K)
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