Vol. 47, No. 11
November, 1998
Toshiaki Nomura**
**Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1, Asahi, Matsumoto-shi, Nagano 390-8621
(Received 11 June 1998)A piezoelectric quartz crystal (PQC) has been used as a microbalance in air as the frequency of the PQC shifts with the mass change of a material adhered on the PQC. The frequency shifts are independent of the species of the material, and depend only on the amount. The specificity for chemical analysis can be obtained from the coating on the surface of PQC having a specificity site. On the other hand, in measurements performed in liquids the frequency shifts resulting from the density, viscosity, conductivity, permittivity and so on in addition to the frequency behaviour of the PQC in air should be considered. Many papers have been published about the frequency behaviours, oscillators, etc. of the PQC, detection cells, coatings, etc. for chemical analyses, and so on. These papers suggest some idea for chemical analyses using a PQC.
Keywords: piezoelectric quartz crystal(PQC); frequency behaviour; frequency change; oscillator; piezoelectric immunosensor; electrode-separated PQC.
Kanji Miyabe**
**Faculty of Education, Toyama University, 3190, Gofuku, Toyama 930-0887
(Received 11 March 1998, Accepted 26 June 1998)An analytical study was made concerning mass-transfer phenomena in reversed-phase liquid chromatography (RP-LC). A moment method was applied for analyzing the properties of chromatographic peaks measured under various conditions related to sample substances as well as stationary and mobile phases. First moment analyses provided some pieces of information concerning the mass-transfer equilibrium in RP-LC. The isosteric heat of adsorption (-Qst) was smaller than the corresponding heat of vaporization. The relatively small value of -Qst could be explained by solvophobic theory. From second moment analyses, it was indicated that the contribution of intraparticle diffusion to the overall mass-transfer resistance in a column was usually important, and that surface diffusion played a significantly dominant role for mass transfer in RP packing materials. The activation energy of the surface diffusion (Es) was larger than -Qst in RP-LC. The correlation between Es and Qst could be quantitatively interpreted based on the absolute rate theory by assuming that surface diffusion was an activated process similar to molecular diffusion in the liquid phase. The establishment of both an enthalpy-entropy compensation effect and a linear free-energy relation was confirmed irrespective of the separation conditions in RP-LC. A nondimensional rate equation was derived on the basis of moment analysis theory. The equation consists of several terms representing the contributions of mass-transfer processes, such as molecular diffusion, eddy diffusion, fluid-to-particle mass transfer, and intraparticle pore and surface diffusions, to peak spreading. The influence of some operational parameters on the column efficiency was numerically analyzed while considering the individual contribution of each term. It was demonstrated that fundamental studies of surface diffusion provided some essential pieces of information for elucidating the separation mechanism in RP-LC.
Keywords: reversed-phase liquid chromatography; mass transfer; surface diffusion; moment analysis; nondimensional rate equation.
Yoshinori Uwamino**
**National Industrial Research Institute of Nagoya, 1-1, Hirate-cho, Kita-ku, Nagoya 462-8510
(Received 28 May 1998, Accepted 8 July 1998)A few decomposition methods were examined in order to determine impurities in sintered alumina, zirconia and alumina/zirconia composite samples. Pulverized samples were severely contaminated by a grinding vessel. A lump (about 0.3 g) of sintered alumina or zirconia sample was decomposed with 10 ml of sulfric acid (1+2) in a Teflon pressure vessel at 230°C for 16~60 h; however, all sintered alumina/zirconia composite samples were not decomposed with sulfric acid (1+2). A lump (about 0.3 g) of the sintered composite sample was decomposed with a mixture of 0.3ml of hydrofluoric acid and 9.7 ml of sulfric acid (1+2) at 230°C for 24 h. It was necessary to match the matrix components (acids, aluminum and zirconium) in standard solutions to those in sample solutions. The proposed methods were applied to several commercial samples, and the impurities and additives were determined by ICP-AES. The detection limits of most elements were below several µg/g. The decomposition methods for sintered silicon carbide, silicon nitride, aluminum nitride, boron nitride, zinc oxide, barium titanate, lead zirconate titanate and sialon were also described.
Keywords: determination of impurities; sintered alumina, zirconia and alumina/zirconia composite; acid pressure decomposition in Tefron vessel; ICP-AES; sintered silicon carbide, silicon nitride, aluminum nitride, boron nitride, zinc oxide, barium titanate, PZT and sialon.
Noriko Ohno** and Tadao Sakai***
**Chemistry Laboratory, School of Business Administration, Asahi University, 1851, Hozumi, Hozumi-cho, Motosu-gun, Gifu 501-0296
***Department of Applied Chemistry, Aichi Institute of Technology, 1247, Yachigusa, Yakusa-cho, Toyota-shi, Aichi 470-0392
Since 1975, many papers related to flow-injection analysis (FIA) have been published, because FIA has great advantages of small reagent consumption, small sample volume, simplicity, reproducibility and rapidity. To enhance some functions on the FI detection system, some instrument devices, such as micro-flow cells and phase separators for the liquid-liquid extraction procedure, were proposed, and their practicality was investigated. A thermo-controlled flow cell was used for the selective determination of choline and acetylcholine. Iron and copper in sera were simultaneously determined using a homemade double-flow cell. A new phase separator with two membranes was available and practical for the solvent-extraction/FIA system. Consequently, the proposed FI systems are useful for analyses of pharmaceuticals and clinical samples.
Keywords: flow-injection analysis; solvent-extraction; two membranes phase separator; double flow cell; thermo-controlled flow cell; pharmaceuticals; clinical sample.
Jun'ichiro Miura**
**Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Fukui University, 3-9-1, Bunkyo, Fukui 910-8507
(Received 1 June 1998, Accepted 28 July 1998)In the reversed-phase high-performance liquid chromatography (RP-HPLC) of metal chelates with azo dyes, surfactants have been used as modifiers and a mobile phase. Two techniques are proposed to develop the selective separation and sensitive detection of chelates. The first is the addition of ionic surfactants to an aqueous organic solvent mobile phase; the second is to use an aqueous micellar mobile phase containing a nonionic surfactant. In the former method, ionic surfactants, such as alkanesulfonate, alkyl sulfate and tetraalkylammonium salt, were shown to be effective for decreasing the retention time of opposite-charged chelates strongly retained on the RP support. In the latter method, the retention time in micellar RP HPLC was successfully controlled by varying the oxyethylene chain length of the nonionic surfactants, in addition to adjusting the concentration of the surfactants. Moreover, the two techniques were combined to develop a rapid and selective separation of ionic chelates with azo dyes. The combined use of an ionic surfactant with micellar RP-HPLC would provide a useful means for enhanced selective separations of many ionic compounds. These proposed methods have been applied to the determination of trace amounts of V(V), Co(II), Ni(II) and Fe(III) in high-purity silicon, environmental samples, such as natural water, and biological samples, such as enzyme.
Keywords: reversed-phase HPLC; micellar HPLC; ionic surfactant; nonionic surfactant; metal chelate.
Yukihiro Esaka**
**Gifu Pharmaceutical University, 5-6-1, Mitahora-higashi, Gifu 502-8585
(Received 22 May 1998, Accepted 21 August 1998)Capillary electrophoresis using polyethers as hydrogen-accepting agents was developed. The addition of PEG as a matrix agent in CZE causes a selective decrease in the electrophoretic mobility of some substituted benzoates having hydrogen-donating substituents. The addition of non-ionic surfactants with a polyether structure to an SDS system for MEKC results in a selective increase in the relative capacity factors of some non-ionic and cationic-substituted benzenes with hydrogen-donating substituents. These effects can be interpreted in terms of a hydrogen-bonding interaction between the ether oxygen atoms of the polyether agents and the substituents of analytes. Separation was well controlled by adjusting the PEG concentration and mixing ratio of the surfactants. The thermodynamic aspects of these separation systems are discussed in detail.
Keywords: hydrogen-bonding interaction; capillary-zone electrophoresis; micellar electrokinetic chromatography; polyethers; mixed-surfactant systems.
Chushiro Yonezawa*, Tatsuya Kurosawa** and Hideaki Matsue*
* Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki 319-1195
**Radiation Application Development Association, Tokai-mura, Naka-gun, Ibaraki 319-1106
(Received 27 April 1998, Accepted 16 July 1998)The rapid determination of ppm levels of F in silicon nitride powder and some reference materials by instrumental neutron-activation analysis (INAA), measuring the short-lived nuclide 20F (half life: 11.00 s), has been studied. The determination was carried out by single and cyclic activation methods using an activation analysis facility (PN-3) of the 20 MW reactor JRR-3M. Using this method, the sample was irradiated with a thermal neutron flux of 1.9×1013 n cm-2 s-1 for 5 s, and the γ-ray spectrum was measured for 10 s after letting the sample stand for 7 s. In the cyclic-activation method, the single-activation method was repeated 5 times, including more than a 10 min cooling interval between each measurement. The effects of evaporating F during neutron irradiation and a side reaction due to 23Na (n, α) 20F were examined; it was confirmed that these effects can be neglected under the present experimental conditions. Due to the high Cd ratio of the irradiation field at PN-3, the effect of the side reaction from Na is 25- to 155-times lower than the values obtained by other reactors. The cyclic-activation method presents not only a lower detection limit, but also better analytical precision than the single-activation method. The analytical results of F in reference materials of Opal Glass (NIST SRM91) and Oyster Tissue (NIST SRM1566a) almost agreed within 5.1 to 5.9 % with the certified and reference values. The relationship between the detection limit of the F and Al contents was also clarified.
Keywords: determination of F; ppm level; silicon nitride; short-lived nuclide; 20F; reference materials; Opal Glass; Oyster Tissue; Tea Leaves; JRR-3M.
Fumie Katsuki, Akiko Hokura, Daigo Iwahata, Takahito Ikuma, Sachiko Oguri and Hiroki Haraguchi*
*Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603
(Received 4 June 1998, Accepted 16 July 1998)The acid digestion of Tea Leaves reference materials (CRM, NIES No. 7) with nitric acid or with nitric acid and hydrofluoric acid was preliminarily examined for a multielement determination of major-to-ultratrace elements in plant samples by ICP-AES and ICP-MS. It was found that matrix effects due to major elements in plant samples on ICP-MS analysis could be corrected by the internal-standard method. The observed concentrations of lanthanoid elements in the samples were corrected by the spectral interference equivalent concentrations of polyatomic ions. On the basis of these fundamental investigations, 41 elements in cherry samples (leaves, petals, calyxes) collected at 9 sampling sites in Nagoya City were successfully determined. In addition, the distributions of the elements were also considered, especially from the viewpoint of the concentration ratios in petals and leaves.
Keywords: ICP-MS; ICP-AES; multielement determination; cherry samples; acid digestion.
Tadao Fukuhara, Kazuo Komatsu, Seiichi Yoshida, Okihiko Sakamoto*, Shinya Yamamoto** and Tasuku Takamatsu*
*Safety & Analytical Research Center, Shiseido Co., Ltd., 1050, Nippa-cho, Kohoku-ku, Yokohama-shi, Kanagawa 223-0057
**Pharmaceutical Department, Kakegawa Factory, Shiseido Co., Ltd., 1120, Nagaya, Kakegawa-shi, Shizuoka 436-0047
(Received 13 May 1998, Accepted 22 July 1998)A semimicro LC/1H-NMR was constructed with a 3 mm i.d. micro-probe equipping a glass NMR flow cell of ca. 50 µl volume. A semimicro polymer-coated ODS column (1.5 mm i.d. ×250 mm) was used for various studies with a mobile phase of D2O, and deuterated an acetonitrile mixture at a 100 µl/min flow rate. Identification and detection limits were determined by a flow-injection mode for ethyl p-hydoroxybenzoate as ca. 5 µg and sub-µg, respectively. A comparison of a UV chromatogram and a protonogram, which was obtained by projecting the on-flow spectrum on the time-axis was made in order to study the state of diffusion of the sample in the NMR flow cell. The results indicated that a separation of adjacent peaks eluted through LC was well maintained in the NMR flow cell. The semimicro system was also applied to a keto-enol tautomeric mixture, which was hardly isolated by a preparative procedure. Each tautomer was identified by the individual spectra of the keto and enol forms, and the usefulness of semimicro LC/1H-NMR has been fully demonstrated.
Keywords: LC/NMR; semimicro LC; keto-enol tautomer.Masashi Nishida, Miwako Sonoda, Daido Ishii and Isao Yoshida*
*Department of Applied Chemistry, Kumamoto Institute of Technology, 4-22-1, Ikeda, Kumamoto 860-0082
(Received 29 June 1998, Accepted 30 July 1998)The extraction-spectrophotometric determination of manganese(II) was studied using tetrasodium calix[4]arene-p-sulfonate(Na414) and trioctylmethylammonium chloride (TMA+Cl-) in chloroform. Manganese(II) forms a reddish-purple 1:1 complex with Na414 in an alkaline aqueous solution; the complex is quantitatively extracted into chloroform from the aqueous solution. By using a tenth part of chloroform in volume, manganese(II) was concentrated in the chloroform phase and its absorbance was measured at 510 nm in a 1 cm light-pass length cell. The apparent molar absorptivity at 510 nm was found to be 8.46×104 M-1 cm-1 per aqueous concentration of manganese(II). The sensitivity increased by about ten times, and the detection limit of manganese(II) was 6.5 ppb. Cerium(III)caused too positive error by forming a colored extractable complex, chromium(III) caused too negative error; however, most of the other foreign metal ions did not interfere with the determination of manganese(II). This method was successfully applied to the determination of manganese(II) extracted with 5×10-4 M sulfuric acid from soil samples.
Keywords: extraction-spectrophotometric determination of manganese(II); tetrasodium calix [4] arene-p-sulfonate; water soluble calixarene; trioctylmethylammonium chloride.
Shin-ichiro Okawa, Kazuhiko Yamazaki and Tosimi Ishikawa*
*Department of Chemistry, College of Humanities and Sciences, Nihon University, 3-25-40, Sakurajosui, Setagaya-ku, Tokyo 156-8550
(Received 24 June 1998, Accepted 10 August 1998)An ion chromatographic method using postcolumn derivatization with 2-(2-benzoxazolylazo)-1-naphthol(α-BOAN) in a nonionic surfactant solution of Brij35 was established for the separation and determination of copper(II) and zinc(II). The optimum conditions for determining the elements were: an eluent containing 0.25 mol dm-3 lactic acid (pH 3.1) at a flow rate of 1 ml min-1; for postcolumn derivatization, a 2×10-4 mol dm-3 α-BOAN solution containing 4%(v/v)dioxane, 4%(w/v) Brij35 and sodium tetraborate at a flow rate of 0.3 ml min-1; pH at the drain of 3.3±0.1; analytical column, a Shim-pack IC-C1(5.0 mm i.d×150 mm); oven temperature of 40°C; an injection volume of 0.02 ml; and detection at 565 nm. A linear relationship was observed between the peak hight and the amount of elements within ranges of 80~240 and 400~2000 ppb for copper and zinc, respectively. The relative standard deviations for the measurements (n=7) of 120 ppb Cu and 800 ppb Zn were 2.2 and 2.0%, respectively; the detection limits of 16 ppb Cu and 195 ppb Zn (S/N=3) were obtained. The present method was applied to the separation and determination of copper(II) and zinc(II) in the Rice Flour (NIST SRM1568a) and Bovine Liver (NIST SRM1577b) with satisfactory results.
Keywords: postcolumn ion chromatography; 2-(2-benzoxazolylazo)-1-naphthol; separation and determination of copper(II) and zinc(II); Rice Flour(NIST SRM1568a); Bovine Liver(NIST SRM1577b).
Minemasa Hida* and Toshiyuki Mitsui*
*Criminal Investigation Laboratory, Aichi Prefecture Police H. Q., 2-1-1, Sannomaru, Naka-ku, Nagoya 460-8502
(Received 29 May 1998, Accepted 13 July 1998)In conventional methods, the determination of nitrocellulose in smokeless powders has been very tedious and time consuming because of using a liquid extraction procedure. In this study, a quantitative analysis of nitrocellulose in smokeless powder was investigated using a multivariate analysis for the infrared spectra. The relative standard deviation of this methods was less than 1%. The nitrocellulose in smokeless powder could be determined accurately and quickly by this method.
Keywords: nitrocellulose; smokeless powder; FT-IR; multivariate analysis; principal component analysis.
Yoshitoki Iijima*, Kousuke Miyoshi** and Syuichi Saito**
*Application and Research Center, Electron Optics Division, JEOL Ltd., 1-2 Musashino 3-chome, Akishima-shi, Tokyo 196-8558
**Crystal Technology Development Laboratory, ULSI Device Development Laboratories, NEC Co., 1120, Shimokuzawa, Sagamihara-shi, Kanagawa 229-1198
(Received 5 February 1998, Accepted 3 August 1998)X-ray photoelectron spectroscopy (XPS) is an effective method for analyzing the chemical bonding state of material surface. The detection limit of XPS, however, is inferior to other analyzing methods, such as SIMS and TXRF. The total reflection XPS (TRXPS) is a method for improving the detection sensitivity. In this study, we examined the validity of TRXPS for the analyzing the contamination on a Si wafer surface. In this experiment, the glancing angle of X-ray(Al-Kα) was 1.1°, which satisfied the total reflection condition. The samples used were Si wafers contaminated by Fe and Cu. The detection limit of TRXPS was found to be 9E+10 atoms/cm2 for Fe and Cu, which was improved by 40 times in comparison with that of the normal-type XPS. Accordingly, it can be said that TRXPS is a very effective method for the analyzing the contamination on a Si wafer.
Keywords: total reflection photoelectron spectroscopy; XPS; TXRF; Si wafer; Fe; Cu; detection limit; sampling depth.
Shigeru Terashima, Masahiro Taniguchi and Takashi Okai*
*Geological Survey of Japan, 1-1-3, Higashi, Tsukuba-shi, Ibaraki 305-8567
(Received 1 June 1998, Accepted 7 August 1998)A five-step sequential chemical-extraction scheme is described for the analysis of B in geological reference materials by ICP-AES. Each of the chemical fractions is operationally defined as follows: 1) 0.1 M potassium nitrate for the ion-exchange and adsorbed fraction; 2) 0.05 M ethylendiaminetetraacetic acid disodium salt (EDTA) for the EDTA soluble fraction; 3) a mixture of 0.025 M EDTA, 0.1 M ammonium oxalate, 0.1 M oxalic acid, 0.05 M ascorbic acid and 0.005 M HCl for the oxide fraction; 4) a mixture of 6 M HNO3 and 1 M HCl for the HNO3-HCl soluble fraction; and 5) fusion with Na2CO3 for the residual fraction. The relative standard deviation for B at levels of 0.15 and 5 µg were 20 and 4%, respectively. The detection limit was approximately 0.8 ppm for a 0.1 g sample. Satisfactory agreement was observed between the sum of the B values from ion-exchange and adsorbed to residual fractions and the reported total B values. Analytical results of B for twenty five geological reference materials, such as igneous rocks, sedimentary rocks, sediments, soils and coal fly ashes were tabulated, and geological and mineralogical features are discussed.
Keywords: fractionation of B; sequential extraction/ICP-AES; geological reference materials.
Kiyoshi Misawa*, Masatoshi Wakisaka*, Tamotsu Sainoo* and Keiichiro Hozumi**
*Yanaco Analytical Instruments Inc., 33, Shimotoba-Osada-cho, Fushimi-ku, Kyoto 612-8471
**Kyoto Pharmaceutical University, 5, Misasagi-Nakauchi-cho, Yamashina-ku, Kyoto 607-8414
(Received 18 June 1998, Accepted 18 August 1998)The determination of organic halogens is mostly carried out by the oxygen-flask method, while very few attempts have been reported for automatic instrumentation of the halogen analyzer. A rapid and simple microanalyzer is therefore proposed using the gas-chromatographic technique by which chlorine, bromine and iodine are qualified and quantified, respectively. A sample of 1~1.5 mg is weighed and ignited instantaneously in a quartz combustion tube at 900°C with a carrier gas comprizing helium and oxygen (1:1) at a flow rate of 20 ml/min. The combustion gas passes through a Teflon column at 60°C packed with methylsilicone oil as a stationary phase. Halogens coming out of the column are then chemically converted to equimolar iodine by contact with silver iodide at 200°C. The iodine vapor is spectrophotometrically detected in a small gas cell incorporated with a light source of 525 nm and a phototransistor. The retention times of the halogen peaks are 4 min for chlorine, 8 min for bromine and 35 min for iodine, respectively. By raising the column temperature to 80°C, however, iodine comes out at 15 min. Since the detector output is proportional to the light transmittance, a computer program was made to transform the signal every one second to the absorbance scale. The integrator prints out the peak data to 5 figures.
Keywords: determination of organic halogens; automatic halogen analyzer; gas-chromatographic separation of halogens; conversion of halogens to iodine vapor; spectrophotometric measurement of iodine.
Masatoshi Nagata
TOSOH Co. Yokkaichi Research Laboratory, 1-8 Kasumi, Yokkaichi, Mie 510-8540
(Awarded by Mie University dated March 25, 1998)A new type of column packed with polystyrene gels having a broad pore-size distribution of particles (henceforth referred to as the multipore column) was developed, and its performance was compared with the so-called linear column (henceforth referred to as the mixed-bed column). A chromatogram of the epoxy resin (Epikote 1009) on the multipore column showed a monomodal distribution, but the chromatogram on the mixed-bed column showed an inflection on the chromatogram at a molecular mass of about 8,000 as the polystyrene equivalent. There was a big difference in the pore-size distributions of gels packed in the two types of columns: the pore-size distribution of the multipore column was trapezoidal, while that of the mixed-bed column had sharp maxima for pores having a diameter of 0.08 mm. This difference in the pore-size distribution may be suggested to be the main reason for the inflection phenomenon, though the shapes of the two calibration curves of these columns were almost similar. The multipore column also had the advantage of a mixed-bed column in the linearity of the calibration curve.
(Received August 11, 1998)Keywords: size-exclusion chromatography, multipore column, pore-size distribution, calibration curve, linearity.
Takashi Tomiyasu
Department of Earth and Environmental Sciences, Faculty of Science, Kagoshima University, Korimoto, Kagoshima 890-0065
(Awarded by University of Tsukuba dated March 25, 1998)In the catalytic method, a kinetic-mechanistic study is important in optimizing the experimental conditions and in extending the analytical utility of the reactions, since a rate equation derived by a kinetic study permits an accurate prediction of the reaction over a wide range of reaction conditions. In this study, the catalytic effects of some trace elements on the chlorpromazine(CP)-hydrogen peroxide reaction were studied both analytically and kinetically. The oxidation of CP proceeds by two independent and parallel reactions: one of them proceeds through a red intermediate; the other goes directly to a colorless sulfoxide. It was found that iodide and iron(II, III) catalyzed the former reaction, and tungsten(VI) catalyzed the latter reaction. Thus, spectrophotometric determinations of iodide, iron and tungsten(VI) based on their catalytic effects on the reactions were developed. According to the results of a kinetic study, mechanisms for both the catalyzed and uncatalyzed reactions were proposed. It was also observed that the sulfoxide formation reaction was catalyzed by molybdenum(VI). The kinetic behavior of molybdenum(VI) and tungsten(VI) were investigated in detail in order to derive their rate equations. The optimum conditions for a differential determination were easily established using the equations. A kinetic study is the most favorable for systematically finding the optimum conditions for a differential determination.
(Received September 7, 1998)Keywords: catalytic method; kinetics; reaction mechanism; chlorpromazine; iodide; iron; tungsten(VI); molybdenum(VI); differential determination.
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