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Volume 34, Issue 11
Displaying 1-19 of 19 articles from this issue
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High performance liquid chromatography of proteins and peptides on an octadecyl-bonded glass supportTohru ICHIMURA, Yasuhiko AMANO, Toshiaki ISOBE, Tsuneo OKUYAMA1985 Volume 34 Issue 11 Pages 653-658
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSReversed phase liquid chromatography of proteins and peptides was performed on an octadecyl-bonded glass support having a mean particle diameter of 5 μm and a pore size of 350 Å. The mobile phase was the mixture of acetonitrile and water containing 0.1%(v/v) trifluoroacetic acid. The content of acetonitrile was increased linearly (gradient mode). Sixteen test proteins having molecular weights of 10000-190000 Dalton, as well as tryptic peptides of calmodulin and of a Bence-Jones protein NIG-77, were eluted within 40 min with considerably high resolution. The recoveries were dependent on the molecular weights of the samples, almost 100% up to the molecular weights of 30000 and then gradually decreased. The recoveries of the proteins having molecular weights of 190000 were about 30%. The retention time of proteins showed a linear relationship (correlation coefficient 0.84) to the molecular weight or hydrophobicity of the proteins. The hydrophobicity of the octadecylbonded glass support corresponded to about 92% of that of octadecyl-bonded silica gel (Develosil ODS) which was estimated from the retention time of calmodulin peptides. We have concluded that the octadecyl-bonded glass support is a useful tool in protein chemistry, which allows the analytical and preparative separation of peptides and proteins of wide molecular weight range.View full abstractDownload PDF (680K) -
Masataka NISHIKAWA, Yoshinari AMBE, Tsuguo MIZOGUCHI1985 Volume 34 Issue 11 Pages 659-664
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSAn evaporation preconcentration of rainwater sample was studied for the analysis of trace elements by inductively coupled plasma emission spectrometry (IC-PAES). The evaporation preconcentration procedure is favorable for multi-elements analysis by ICP-AES because most of the elements, except for mercury and other volatile ones, can be enriched simultaneously. A conventional type of rotary evaporator was reformed setting a newly designed sample vessel made of teflon inside the glass bottle which can be separated into two parts, and compared to the former type of evaporator having a vessel made of hard glass. From the experiments using twice distilled water it was found that small amount of B, Na, Mg, Si, and Ca dissolved out from the surface of the glass vessel giving some positive error. From the teflon vessel, however, no contamination of elements was detected. When removing the cotent from the vessel into a measuring cylinder, adhesion of tiny amount of concentrated sample water occurred on the surface of the vessel to cause an error in the calculation of the enrichment factor. It was found that the volume of the adhered solution on the surface of a glass flask was nearly constant (0.5 ml) independently of the volume of the solution under this conditions, and using this value the correction of the result was possible. Such an adhesion, on the other hand, was not observed for the case of teflon vessel within the accuracy of our experiments. In conculusion, although the improved rotary evaporator with a teflon vessel is not more time-saving than a conventional glass evaporator, it is more advantageous in the following items; (1) No dissolution of element from the surface of the cocentration vessel; (2) High efficiency in preconcentration of rain samples (1000 ml to 1 ml) ; (3) No backward flow of condensed water on the glass part of the evaporator into the teflon vessel.View full abstractDownload PDF (800K) -
Kiyoshi MUSHA, Heihachiro TADA, Chikakiyo NAGATA, Shigeyuki TANAKA1985 Volume 34 Issue 11 Pages 665-670
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESS13C-NMR spectroscopy was applied to the analysis of various water-soluble polymers used industrially from the analytical point of view. 13C-NMR spectra were measured in D2O solutions using a JEOL JNM-FX90Q FT-NMR spectrometer at 22.53 MHz with complete proton decoupling and gated (non-NOE) decoupling techniques. 13C-NMR spectra were examined in detail and were found to give important information about polymer structures shown as follows: (1) identification of monomers in a collagen peptide, poly (acrylic acid), and poly (acrylic acid-maleic acid), (2) structural analysis of amine-epichlorohydrin copolymer which is synthesized in water and its structure is changed by removing water, (3) discrimination between block and random copolymers of ethylene oxide-propylene oxide; the variation of the monomer sequence distributions is related closely to that of properties such as surface activity, (4) analysis of stereoregularity in poly (vinyl alcohol-vinyl acetate) and poly (N-vinyl-2-pyrrolidone). These are all difficult problems to solve by infrared and 1H-NMR methods. Thus, 13C-NMR spectroscopy was indicated to be useful for the characterization of polymer structures.View full abstractDownload PDF (830K) -
Takahiro KUMAMARU, Yoko NITTA, Hiroshi MATSUO, Shigeki HARA1985 Volume 34 Issue 11 Pages 671-676
Published: November 05, 1985
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSAn extraction system with tetradecyldimethylbenzylammonium (Zephiramine)-iodoaurate(III) or iodoplatinate(IV)-chloroform was investigated for the use of a pretreatment procedure in an inductively coupled plasma atomic emission spectrometric determination of gold and platinum. Gold(III) and platinum(IV) were extracted quantitatively into chloroform over the ranges of 4 mol dm-3 HCl to pH 13 and of 4 mol dm-3 HCl to pH 11, respectively, provided that the concentrations of Zephiramine and potassium iodide in the aqueous phase were each kept at 2.0×10-3 mol dm-3 and 0.16 mol dm-3. When the aqueous/organic phase volume ratio was 25 cm3/5 cm3, the linearity of the emission intensity vs. the concentration was observed up to 1.5 mg/25 cm3 (60 μg cm-3) for both metal ions. The detection limits (3σ) for gold(III) were 2.7 ng cm-3 (Au I 267.595 nm) and 4.3 ng cm-3 (Au I 242.795 nm), and those for platinum(IV) were 5.8 ng cm-3 (Pt II 214.423 nm) and 11 ng cm-3 (Pt I 265.945 nm). The relative standard deviations measured at each analytical line from 10 runs were 12% for each 10 μg/ 25 cm3 (0.40 μg cm-3) of gold(III) and platinum(IV). The result of a general investigation, involving 43 cations and anions, of interferences was shown. The proposed method was applied to the analysis of goldsilver alloys.View full abstractDownload PDF (831K) -
Kazuo WATANABE, Misao OUCHI1985 Volume 34 Issue 11 Pages 677-681
Published: November 05, 1985
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSA known quantity of deuterium (80800 μg) was heated with the metal sample at about 700°C in order to be absorbed almost completely into the sample as the temperature was lowered down to about 450°C. The sample thus prepared was then heated to 830850°C. The resulted equilibrated hydrogen was led into a one-litre sampling bottle for subsequent mass spectrometry. The results obtained are dependent on the recovery of the equilibrated hydrogen on account of the isotope effect on the solubility between hydrogen and deuterium in the metals. As hydrogen is more soluble than deuterium, the isotope composition of hydrogen in the gas phase differs significantly from that in the solid sample in the isotopic equilibrium. When the values of recovery are less than 10% of the total amount of the equilibrated hydrogen, analytical values become about 14% lower than the true value. The recovery over 70% of the total amount assures accurate result. Values for 60μg H/g titanium plate showed large deviations because of inhomogeneous distribution of hydrogen in the sample plates. Reliable average hydrogen contents of these samples were obtained by cutting the samples in small pieces and to mix them thoroughly. The relative standard deviation is 17% for hydrogen contents in the range 860 μg/g.View full abstractDownload PDF (806K) -
Susumu NAKAMURA, Yoshinori KOBAYASHI, Masaaki KUBOTA1985 Volume 34 Issue 11 Pages 682-685
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA commercial atomic absorption spectrometer was modified to detect signals with fast response. A spectrometric part with a photomultiplier was used without any modification. Distortion of absorbance and temperature signals caused by a measurement system with time constant circuits was decreased by the following modifications. The output of the photomultiplier was fed into a computer through a pre-amplifier and an A/D converter. A pyrometer with a smaller capacitance was used for measurements of furnace temperature. The distortion of absorbance and temperature signals by the present system was shown to be negligibly small by experiments employing a fast shutter. The absorbance and temperature signals observed by the present system coincided within experimental errors with those calculated from the data measured by a commercial instrument according to a distortion function model reported previously.View full abstractDownload PDF (556K) -
Kunio NAKANO, Nakahide KATO, Makoto NISHIDA, Yayoi TANAKA, Masaki NAKA ...1985 Volume 34 Issue 11 Pages 686-691
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSDerivative time-root potentiometry can eliminate the disadvantage of conventional chronopotentiometry and a derivative time-root potentiogram can be treated as an ac polarogram. And this method requires shorter time for the measurements than polarography and the half-wave potential can be easily obtained from the peak potential. A derivative time-root potentiograph of analog device was constructed. However, its characteristics depended strongly on the time constant of the differential circuit, that is, to increase the time constant resulted in to suppress the peak height of the signal in the earlier stage, and when the time constant was small, the later signal was buried in the noise. Consequently, the determination was limited only in a narrow concentration range. For example, Ti(IV), Cd(II) and Pb(II) could be determined between the range from about 0.1 to 0.4 mM. Therefore, the derivative time-root potentiograph with a microcomputer was assembled and a computational method was employed for the differential operation instead of the analog circuit. The treatment of data was as follows: An original chronopotentiogram was smoothed by 5 points moving average and then it was converted into a time-root potentiogram. The potentiogram was again converted into a curve of uniform interval voltage (1 mV) and then it was differentiated. This operation resulted a reproducible peak potential and peak height, which was proportional to the sample concentration. Pb(II) can be determined between the range from 0.16 to 2.2 mM by means of this method. This suggests that read-out method as a derivative time-root potentiogram with a microcomputer will be useful way of determination.View full abstractDownload PDF (819K) -
Yoshinobu BABA, Yoshisuke YAMAMOTO, Norimasa YOZA, Shigeru OHASHI1985 Volume 34 Issue 11 Pages 692-694
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA flow injection system, interchangeable as a high performance liquid chromatographic detector, was designed for the rapid determination of nucleotides (AMP, GMP, IMP, CMP, and UMP) as well as inorganic phosphates. A sample solution was injected into a carrier stream of water and then mixed with an acidic molybdenum(V)-molybdenum(VI) reagent solution. In a reaction coil (150°C) phosphorus compounds were hydrolyzed and the resultant orthophosphate was allowed to react with the molybdenum reagent to produce a heteropoly blue complex. The absorbance of the blue complex was monitored at 830 nm. The hydrolytic process determined the detection sensitivities of phosphorus compounds. The sensitivities of nucleotides and diphosphate relative to the maximal sensitivity (100%) of orthophosphate were ca. 15% for purine nucleotides, ca. <2% for pyrimidine nucleotides, and 100% for diphosphate, respectively. Sampling rate was 78 samples/h. The precision (R.S.D.) was between 0.4 and 4.3%. The flow injection method was found to be useful for the purine nucleotides analysis.View full abstractDownload PDF (462K) -
Noriko OHNO, Tadao SAKAI1985 Volume 34 Issue 11 Pages 695-700
Published: November 05, 1985
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSQuinine cation (H·Q+) was extracted into organic solvents with diprotic acid dyes, such as bromophenol blue (BPB) and bromocresol green (BCG), to form a 2:1 ion-associate, (H·Q+)2·BPB2- or (H·Q+)2·BCG2-. These ion-associates exhibited characteristics of charge transfer complexes and showed reversible thermochromism. The ratio of decrease of absorbance to temperature change (ΔA/Δt) was in propotion to the quinine concentration in aqueous phase (ΔA=A20°C-A45°C, Δt=45°C-20°C), and a good linearity was obtained within a wide concentration range of quinine 0.43.0×10-5 M. BPB-quinine associate extracted into chloroform at pH 6.5 had an absorptionmaximum at 590 nm. Maximum absorbance wavelength of BCG-quinine associate at pH 7.2 was at 550 nm in 1, 2-dichloroethane and the calibration graph was linear throughout the concentration range of 1.05.0×10-5 M quinine. Procaine, ephedrine, eserine, papaverine, triethanolamine, and tetraethylammonium did not interfere with the quinine assay in 510 fold ratio. Neither diphenhydramine, chlorpheniramine, and dibucaine in 0.51.0 fold molar excess over 1.2×10-5 M quinine had influences. Consequently, this method was proved to be selective for quinine determination compared with other spectrophotometric methods. In addition, the absorbance of ion-associates increased with a decrease in temperature; that is, the absorbance at 10°C was 24% larger than that at 20°C. The increase in absorbance with cooling seemed to be due to the enhanced ion-association in the organic phase. This method can be applied to selective determination of quinine in tablets. Furthermore, sensitivity of the method can be increased by lowering temperature of ion-associates.View full abstractDownload PDF (964K) -
Kazuyoshi TANAKA, Nobuyuki KASHIHIRA, Kuwako KIRITA, Yoshichika WATANA ...1985 Volume 34 Issue 11 Pages 701-706
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe coexistent substances cause a detectable shift or drift in gas-sensing electrode potential at low levels of ammonia. Electrode response is a function of ammonia concentration, and considerable response times are required for the steady-state potential below 10-4 mol dm-3 ammonia. The applicability of potentiometric Glan's plots for determining ammonia at these low levels was studied on the basis of response time characteristics, and the theoretical equation of response time was proposed. The definition of response time adopted in this work is the time taken for the electrode response to attain a value 1 mV lower from the steady-state potential. As a result, Glan's plots is available for simple determination of low level of ammonia. Preliminary studies on relative errors were made in (0.34.0)×10-5 mol dm-3 ammonia solutions containing potassium sulfate, copper(II) ion and/or EDTA, indicating that Glan's plots is superior to the other methods of known addition and calibration. The environmental samples of sediments, sand, and soil were digested by Kjeldhal method using potassium sulfate and copper sulfate as decomposition reagents, each 5 ml of 100 ml solution obtained was made up to 100 ml and 19 ml aliquot was transferred to 30 ml beaker for ammonia analysis. The present method was applied directly to determine ammonia in these samples prepared without steam distillation procedure, and the results showed a reasonable agreement with those obtained by conventional Indophenol Blue method.View full abstractDownload PDF (854K) -
Akio OZAWA, Hiroe JINBO, Harumi TAKAHASHI, Takao FUJITA, Aizan HIRAI, ...1985 Volume 34 Issue 11 Pages 707-711
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSIt is well known that prostaglandins and their related compounds, e.g., eicosanoids play important roles in the regulation of cell functions. Eicosanoids have been reported to be derived from eicosapolyenoic fatty acids which are released from cell membrane phospholipids. In order to investigate the distribution of eicosapolyenoic fatty acids in phospholipid subfractions of human platelets, we established an improved method using thin-layer chromatography (TLC) for the separation of phospholipid subfractions and gas chromatography equipped with a solvent-less sample injector for the determination of fatty acids. Lipids of sonicated human platelet suspensions were extracted with chloroform-methanol solution (2:1, v/v) in the presence of butylated hydroxytoluene (BHT) at room temperature for 60 min. Phospholipid subfractions extracted from platelets were separated by one-dimensional TLC on silica gel plates with a solvent system consisting of chloroform/methanol/acetic acid/formic acid (50 : 30 : 4.5 : 6.5, by volume). The areas corresponding to the phospholipid subfractions were detected with the spray of 8-anilinonaphtalenesulphonic acid ammonium salt (ANS). Phospholipids were extracted from the silica gel plates with chloroform/methanol (1 : 4, v/v) once and methanol twice. Methyl esters of fatty acids in phospholipid subfractions were prepared with boron trifluoride and methanol. The fractions of the esters were analyzed by gas chromatography using a Shimadzu GC-7APTF gas chromatograph with a hydrogen flame ionization detector. C23:0 was used as an internal standard. Reproducibilities (R.S.D. value) of the determination of 20 : 4ω6, 20 : 5ω3, and 22 : 6ω3 in platelet phospholipid subfractions by this method were less than 8% in phosphatidyl ethanolamine (PE) fraction, less than 9% in phosphatidyl choline (PC) fraction, less than 16% in phosphatidyl serine (PS) fraction, less than 19% in phosphatidyl inositol (PI) fraction, and less than 20% in sphingomyelin (SM) fraction. As a clinical application of this method, fatty acid distribution in phospholipid subfractions of platelets were determined in healthy male subjects who ingested a highly purified ethyl ester of 20 : 5ω3 for 4 weeks. A significant increase in 20 : 5ω3 was observed in PC, PE, PS, and PI fractions, while a significant decrease in 20 : 4ω6 was observed only in PC and PE fractions. This newly developed method will be useful for the basic and clinical studies owing to its high reliability.View full abstractDownload PDF (765K) -
Shoichiro TAGAMI, Ukiko MORI1985 Volume 34 Issue 11 Pages 712-716
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThis paper describes a method for the development of a methylamine electrode using a gas-permeable membrane and for the determination of pesticide 1-naphthyl N-methylcarbamate. The electrode was prepared by the use of a body of a commercially available ammonia electrode in which the ammonium chloride internal filling solution is replaced by the methylamine hydrochloride solution. The effect of various internal filling solutions on the Nernstian slope of the electrode in the concentration range of 10-510-2 M methylamine was examined by employing solutions with 0.0010.5 M methylamine hydrochloride. The electrode using 0.0010.005 M filling solutions, the slope was a convex curve. With 0.01 M and 0.1 M filling solutions, linear calibration curves were obtained in the methylamine concentration range of 2×10-55×10-3 M and 2 × 10-5 10-2 M, respectively. Using a 0.05 M filling solution, a linear calibration curve was obtained at 10-5 10-2 M methylamine and the potential difference (Δ mV) per decade increase in methylamine was about 59 mV. The response times became short with an increase in methylamine concentration, but the retention times at maximum point of the potential decrease with an increase in the concentration. A 0.05 M filling solution is considered suitable for potential measurements. The response time required for the electrode potential to reach its equilibrium value was 6 min and the retention time was 13 min. Pesticide 1-naphthyl N-methylcarbamate decomposes into α-naphthol, carbon dioxide, and methylamine on refluxing 6 M hydrochloric acid for 2 h. After neutralization with sodium hydroxide solution to pH 6, the methylamine obtained was determined with the methylamine electrode. The sample concentration was determined from the calibration curve using methylamine solution. The purity of the examined sample was estimated as 100.14%.View full abstractDownload PDF (645K) -
Kazue TANI, Yoshihito SUZUKI1985 Volume 34 Issue 11 Pages 717-722
Published: November 05, 1985
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSThe samples used were phenylhydrazones, ο-and p-nitrophenylhydrazones and 2, 4-dinitrophenylhydrazones of aliphatic saturated aldehydes from methanal to heptanal and their isomeric ketones. The chromatographic separation of these derivatives was carried out on an ODS column with aqueous 75% methanol as a mobile phase. ο-Nitrophenylhydrazones more slowly eluted than the other derivatives of compounds having the same number of alkyl chain. The ο-nitrophenylhydrazones were thought to be fixed in a planar conformation by an intramolecular six-membered ring formed through hydrogen bond between the hydrazone -NH- and the oxygen of the nitro group. The formation of the intramolecular hydrogen bond would inhibit to decrease the number of hydrophobic sites. This decrease in solute-solvent association then should produce a decrease in solute polarity resulting in greater chromatographic retention. Since para substituted nitro group produced an increase in solute-solvent association, 2, 4-dinitrophenylhydrazones eluted before ο-nitrophenylhydrazones for each set of compounds. The phenylhydrazones and p-nitrophenylhydrazones of aldehydes displayed a higher affinity for the stationary phase than those of the isomeric ketones. On the other hand, the ο-nitrophenylhydrazones of aldehydes and isomeric ketones exhibited similar chromatographic behavior. This behavior was considered to be due to the formation of the intramolecular hydrogen bond and the disturbance of decreasing the number of hydrophobic sites, which was greater in the ο-nitrophenylhydrazones of isomeric ketones than in those of the aldehydes.View full abstractDownload PDF (782K) -
Effects of added metallic salts on the signal width of OH protons of various metallic salts;uYohichi SUZUKI, Ichiroh ANAZAWA1985 Volume 34 Issue 11 Pages 723-726
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe NMR spectrum of OH protons for a mixture of ο- and p-cresols in acetone was found to split upon the addition of a trace amount of metallic salts such as cadmium nitrate and mercuric halides. The NMR signal of water molecule contained in a solvent or cresols became detectable upon the addition of metallic salts. These results suggest that the intermolecular proton exchange between ο- and p-cresols was accelerated by a trace amount of water. Effects of mercuric halides increased in the order of iodide, bromide, and chloride. The pH value of a mixed solution decreased over a concentration range corresponding to that of NMR spectral change of OH protons. From these results, the spectral change of OH protons upon the addition of metallic salts was assumed to be caused by the following mechanism: The solvent and phenols contain a trace amount of water that can not be removed completely, which reacts with phenols to form oxonium compound. This oxonium compound probably serves to greatly accelerate the intermolecular proton exchange. However, the proton contained in oxonium compound is oriented to the anionic ligand having high proton receptivity when metallic salt is added to mixed solution. Accordingly, oxonium compound is reduced the function for cation, the intermolecular proton exchange is retarded.View full abstractDownload PDF (498K) -
Shigehisa IWAHORI, Rieko MIURA, Ryokichi MURAI1985 Volume 34 Issue 11 Pages 727-729
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSAccording to a metal chelate extraction method, the complex formation of cadmium(II) in aqueous 1 M Na (X, ClO4) was studied in order to calculate the stability constants. Here X stands for chloride, bromide, or iodide ions. Then, the solvent extraction of cadmium(II) in these aq. solutions with trioctylphosphine oxide diluted with hexane was observed. Based on the results obtained the extraction constants of the metal species were determined. It was found that species of Cd(ClO4)2(TOPO)4, CdX(ClO4)(TOPO)3, and CdX2(TOPO)2 were extracted and that the extraction became better with the increasing halide ion concentration. The extraction of cadmium(II) is better than that of zinc(II) under the identical conditions except for the chloride systems.View full abstractDownload PDF (324K) -
Harumitsu NISHIKAWA, Tomokuni HAYAKAWA1985 Volume 34 Issue 11 Pages 729-732
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA method for the determination of gaseous acrolein by gas chromatography with ECD has been developed. Sample gases (340l) were collected in absorption solution of ethanol at the rate of 0.5l/min. After 5 ml of the absorption solution was diluted to 25 ml with water, this solution was brominated at pH 2. The excess of bromine was reduced with sodium thiosulfate solution and 4 ml of phosphorous buffer (pH 8) was added. The derivative of acrolein was extracted with 5 ml of ethyl acetate for three times. The extract was made up to 20 ml with ethyl acetate and 5 μl of this solution was injected into a gas chromatograph with ECD. The lower limit of determination was about 5 nl/l at a size of 40 l of sample gas. The recovery of standard gas was 94% and the relative standard deviation was 8.7% (n=4).View full abstractDownload PDF (486K) -
Shigeki ABE, Shunsuke FUNATA1985 Volume 34 Issue 11 Pages 732-735
Published: November 05, 1985
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSUptake of fluoride ions by hydroxyapatite (HAP) has been investigated. The adsorption characteristics of HAP in sodium fluoride and hydrofluoric acid differ remarkably from one another. At low fluoride concentration, the uptake of fluoride ions takes place through ion-exchange between OH- ions in the HAP particles and fluoride ions in solution. The extraordinarily high uptake of fluoride ions was observed in the wide concentration range of hydrofluoric acid where an uptake minimum was found at about 100 ppm of fluoride. The degree of crystallisation of HAP does not affect the uptake of hydrofluoric acid at higher concentration. A consideration of ion-exchange capacity suggests the second uptake mechanism at high hydrofluoric acid concentration. X-ray diffraction patterns of HAP treated with hydrofluoric acid show a new prominent peak at d=3.14 Å and differ from those of HAP, fluoroapatite, calcium fluorophosphate, and calcium fluoride.View full abstractDownload PDF (468K) -
Toshiaki Koizumi, Hirozo YOSHIMURA1985 Volume 34 Issue 11 Pages T143-T147
Published: November 05, 1985
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSTo keep the marine environment clean, an analytical method for PCB concentration in waste oils had to be devised to meet the requirement for disposal treatment. The legal criterion of marine disposal which can be dumped into ocean and the incinerated on board has provided that the highest contamination of PCB in the waste oil or waste muds must be within 0.15μ/g. But usual technique of PCB analysis does not detect such a low level in waste substances including large amount of mineral oil because the usual pre-treatment by simple combination of silica gel and florisil column chromatography can not remove the large amount of hydrocarbons sufficiently. The partitioning extraction by dimethylsulfoxide (DMSO) and washing by fuming sulfuric acid were added to the scheme of the refining procedure, that is, florisil dry column clean up, DMSO partitioning extraction, digestion by potassium hydroxide-ethanol solution, silica gel column clean up and washing by fuming sulfuric acid were convined in the final pre-treatment system. Experimantal results using the carrier of fuel oils were able to determine 0.1 ppm of PCB, with 87% of recovery. The partitioning extraction using DMSO was given extremely higher recovery than the acetonitrile-hexane partitioning extraction and washing by fuming sulfuric acid was effective treatment for the removal of organochloric pestisides and phthalate esters originated from environmental contamination. The chromatogram of a PCB-spiked waste oil sample was almost the same as that of the mixed standard of PCB.View full abstractDownload PDF (642K) -
Akiyoshi NOZAWA, Minako IMURA, Yoshihisa OTAKA1985 Volume 34 Issue 11 Pages T148-T151
Published: November 05, 1985
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSThe method consists of clean filtration with cleaned nuclepore filter of 20 ml of sample solution, for example, photoresist, gelatin solution for color filter, diluted with cleaned solvent, and counting of stained particles on the filter using an optical microscope in the transmission mode. Viscous samples were diluted with solvent as small amount as possible to the viscosity low eough nfor the following filtration. The gelatin solution had to be hot filtered. As the number of particles found on the filter is extremely small, it is important to clean the filter perfectly before the filtration. It was possible only in the case of polyester nuclepore filter. Differential interference mode and dark field reflection mode observations are not good because the topography of the filter surface is too much emphasized. Particles of ≥0.2 μm can be counted using × 1000 magnitude and the immersion oil. Computer image analysis had a good correlation mith the direct observation by the operator. 2002000 particles per ml were detected in the above mentioned samples, the contribution of the blank being about 20%. All the operations except the microscope observation were carried out carefully in a clean room of class 100.View full abstractDownload PDF (493K)
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