The distribution rates of acetylacetone between water and carbon tetrachloride have been determined by stirring the two phases at various speeds while maintaining a quiescent interface at a constant area. When the stirring speed of the phases is high, the distribution rates have been little affected by stirring speeds. The results have been analyzed quantitatively by considering two rate-determining steps of diffusional and interfacial controls in aqueous and organic bulk regions and in an interfacial region. The measurements have been carried out at 10, 25, 40°C, and the activation enthalpies of interfacial transfer have also been estimated.

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The inspections of stacking faults of Si-wafer were carried out by means of a home-made photoacoustic microscopy (PAM). The stacking faults, which are not observed by an optical microscope, could be measured non-destructively and the depth of stacking faults beneath the surface could also be estimated by PAM.

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By eliminating the interfering effect of the oxygen reduction with the aid of a microcomputer, the voltammetric determination of trace uranyl ions after preconcentration on the TOPO-coated glassy carbon electrode was possible in the presence of dissolved oxygen. A voltammogram for the reduction of dissolved oxygen was obtained just before the preconcentration of uranyl ions. It was subtracted from the voltammogram measured after the preconcentration, in which the reduction wave for the concentrated uranyl ions and that for dissolved oxygen were overlapped. The resulting voltammogram was then differentiated, and the peak current for the derivative curve was measured. For the determination of uranium, a standard addition method was employed. The method could be applied to sea water samples by only adjusting their pH to 4.0.

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The charge shift correction which utilizes the 4f_7/2 binding energy (E_b) of evaporated gold as the reference is investigated for BN, InP, SiO₂ and Al₂O₃ substrates. The change in the final-state relaxation process in low coverage region (_??_2 monolayers) produces inaccuracy of as much as 1eV of binding energy, determined by the gold evaporation method. It is possible to use the 4f_7/2 binding energy of evaporated gold as an energy reference in X-ray photoelectron spectroscopy in the coverage region above 2 monolayers.

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A computer-aided microanalyzer (CMA) developed as a new instrument for comprehensive state analysis of iron and steel samples is described with respect to its principle, apparatus, method and application in that order. The instrument irradiates a sample by an electron beam in vacuum and measures generated characteristic X-rays. After repeating this series of operations at each of over 10⁴analysis spots, the CMA processes the measured values with a computer, and displays the images in order to analyze the macroscopic and microscopic segregations of elements in samples, 0.5×0.5 to 100×100mm in size. Besides these basic functions, it can also perform the comprehensive state analysis of samples, including the analysis of carbon equivalent (C_eq) and inclusions. It is expected to find effective use in applications other than the analysis of iron and steel samples.

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The dynamic response of ISE has been measured with respect to the perturbations of two external electric fields, weak and strong: the first was the field of the environmental electromagnetic waves in space and the second was a static electric pulse field applied to the surface of the ISE. The ISE′s can be classified into two types by the responses to the weak perturbation: in one the surface is capacity-dominant and in the other it is conductivity-dominant. The Ag⁺, Cu²⁺ and Pb²⁺ ISE′s belong to the former and those of F^-, Cl^-, Br^- and I^- to the latter. The response of the former type ISE′s to the strong perturbation has two different relaxation times, τ′s: one (X) is around a few μs or shorter and the other (Y) is in a range around 20 or 5μs for Cu²⁺ and Pb²⁺, respectively. The results of the weak and the strong perturbation coincide in the classification of the ISE′s. The ISE′s which are classified as the conductive ones miss X and Y, except F^- electrode which shows τ of 80μs. No frequency dependence of τ can be measured for X, but Y values for Cu²⁺ and Pb²⁺ have a requency dependence with the optimum at around 800Hz.

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Apparatus has been devised for the determination of the gas exchange and permeation of fertile duck eggs. The oxygen uptake of fertile eggs was measured continuously, and lead the condition of the embryos whether they were dead or alive during incubation. The apparatus for the determination of gas permeation simultaneously determine oxygen, water and carbon dioxide which permeate through the eggshell. By the record of the oxygen consumption for the fertile eggs, the development of the embryos in the course of incubation could be traced. Relations between the gas permeation of the fertile eggs and the growth of the eggshells was also revealed in connection with the oxygen demand.

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A series of liquid anion-exchange extractants R₃P⁺-Y-P⁺R₃, polymethylenebis(trioctytphosphonium)s (Y=(CH₂)_n, n=2, 3, 4, 6, 10) and xylylenebis(trioctylphosphonium)s (Y=o-, m-, p-xylylene), were synthesized. These are lipophilic diphosphonium ions bearing two cationic centers at various distances within a molecule. The extraction of organic sulfonate anions, α-naphthalenesulfonate (NS^-) as well as 1, 5- and 2, 6-naphthalenedisulfonates (NDS^2-) was investigated by using these extractants. From equilibrium studies, the monoanionic sulfonate (NS^-) was found to be extracted via the stepwise formation of 1:1 and 1: 2 ion pairs, while the dianionic sulfonates (1, 5- and 2, 6-NDS^2-) formed 1:1 ion pairs for all of the diphosphonium extractants. The extractability of NDS^2- exhibited a remarkable dependence on the distance separating two ionic centers in the dicationic extractants as well as in NDS^2-. The extraction of NS^- did not show such an effect. A mechanism is discussed for the recognition of interionic distance in the extraction of di-ionic substrates.

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Various metal oxides (MOx′s), formed either as composites or films, were studied as possible materials for the fabrication of a faradaic pseudo reference electrode (FPRE). The basis of the reference was the constant current electrolysis of water to oxygen where the potential depended logarithmically on the current due to the irreversibility of the electrode reaction. It was anticipated, that with judicious choice of the MOx and the current level, that interferences could be minimized in comparison with a reversible, potentiometric reference electrode, particularly for in-vivo application. The properties of RuO₂ on Ti substrate or as a composite (graphite/Kel-F), Pt, and Pt particles dispersed in a polymer film on glassy carbon were investigated as possible FPRE. In the case of Pt, the surface of the electrode is assumed to be platinum oxide at anodic potentials.

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A water-insoluble complexing material, 2, 5-dimercapto-1, 3, 4-thiadiazole loaded on silica gel (DMT-SG), is described for simple preconcentration of trace amounts of bismuth(III) from water samples. In batch experiments, bismuth(III) was quantitatively retained on the DMT-SG from solutions of 0.2-0.5mol dm^-3 nitric acid. The complexing capacity of the DMT-SG for bismuth was 17μmol g^-1 at 0.2mol dm^-3 and 11μmol g^-1 at 0.5mol dm^-3 nitric acid. Bismuth retained on the DMT-SG column was completely eluted with 10cm³ of 0.05mol dm^-3 EDTA solution; the amount was determined by a modified iodide-complexes spectrophotometry or atomic absorption spectrometry. Halogenide ions strongly hindered the retention of bismuth, due to a competitive reaction for the element with DMT. The present method is useful for preconcentrating trace amounts of bismuth from water samples containing less than 2g dm^-3 of chloride ion.

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The atomic absorption of calcium with air-acetylene flame is interfered with by the presence of phosphate. It was found that the interference was reduced by adding Triton X-100 into the calcium solution. The absorption of calcium containing phosphate increased rapidly as the concentration of Triton X-100 increased, and reached a maximum value. Then it decreased to a minimum value and again gradually increased to a constant absorption value as the concentration of Triton X-100 increased. The maximum absorption of calcium appeared in the presence of low concentrations of Triton X-100; this was attributed to the decrease of surface tension, the decrease of the size of sprayed droplets, and the increase of the sample uptake rate. The enhancement effect of Triton X-100 in its higher concentrations was attributed to the reducing action of ultra-fine carbon particles produced in the flame. Several organic substances of large molecular weight which dissolve in water, such as tetramethylammonium chloride, tetraethylammonium chloride, etrapropylammonium chloride, tetrabutylammonium chloride, tiron and tannic acid, were also effective in enhancing the calcium absorption. The analysis of calcium containing phosphate could be carried out in the presence of Triton X-100 in its higher concentrations.

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A technique for the determination of Cr(III) and Cr(VI) species is described which is based on an on-line ion chromatographic separation-inductively coupled plasma atomic emission spectrometric detection (IC-ICPAES). Improved sensitivity and shortened retention time of Cr(VI) are attained by the complex formation of Cr(III) to tetrathiocyanatochromate(III) anion prior to injection and the combined use of a short column (4.0mm I.D.×10 mm) packed with a porous polyacrylate-based anion exchange resin and an eluant of a 5.0×10^-4mol dm^-3 potassium hydrogen phthalate solution (pH 6.5). The ICPAES is used as a selective detector by observing chromium emission at 283.563nm. Detection limits are 7.5ng for Cr(III) and 22ng for Cr(VI). For a typical sample injection volume of 100mm³ these detection limits correspond to 75ng cm^-3 for Cr(III) and 220ng cm^-3 for Cr(VI) in concentration This method can be applied to the fractional determination of Cr(III) and Cr(VI) in waste water samples.

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A method for the extractive spectrophotometric determination of palladium(II) with di-2-pyridyl ketone benzoylhydrazone (DPKBH) has been studied. The method is based on the formation of the palladium(II)-DPKBH complex which is extracted into benzene from sulfuric acid solution in the presence of chloride ions. The extracted species has absorption maxima at 455 and 481nm with the molar absorptivity of 9.38×10³ Lmol^-1 cm^-1 at the former wavelength. Beer′s law is obeyed over the range 0-10μg ml^-1 of palladium at 455nm. The proposed method is selective in the presence of tartaric or citric acid and has been satisfactorily applied to the determination of palladium in a dental alloy and in palladium-catalyst samples.

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A new, heterocyclic hydrazone ligand, 2, 2′-diquinolyl-2-quinolylhydrazone(DQQH), is synthesized and used for the spectrophotometric determination of traces of cadmium(II). Cadmium(II) is preliminarily extracted as the iodide complex into mesityl oxide from sulfuric acid solution. The cadmium(II) is converted to a strongly colored complex by the subsequent treatment of the extract with a DQQH solution in benzene in the presence of an ammonia-sodium hydroxide solution. The analytical species of interest has an absorption maximum at 552nm and obeys Beer′s law over the range up to 9×10^-6M(mol dm^-3) cadmium in the organic phase. The molar absorptivity is 9.15×10⁴ dm³ mol^-1 cm^-1 at 552nm. The composition of the cadmium(II)-DQQH complex and the effect of foreign ions on the determination of cadmium are also investigated.

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A method based on solvent extraction and inductively coupled plasma emission spectrometry (icpes) is described. It was useful in the simultaneous determination of trace elements. The pH dependence of the extractability of 55 ions with a mixture of ammonium tetramethylenedithiocarbamate(APDC) and hexamethyleneammonium hexamethylenedithiocarbamate(HMAHMDC) into xylene was studied systematically. The percentage extraction of each ion at the optimum pH range was also examined. 27 ions proved to be extractable simultaneously by a single extraction. To simplify the procedures and to lower the contamination from the preconcentration steps, xylene is directly introduced into the plasma without back-extraction, and is subsequently analyzed by icpes. Advantages of this method include rapidity, multi-element capability, and high detection capability. The detection limits for 29 elements are also reported. The present method was successfully applied to the analysis of NBS-SRM 1571, Orchard Leaves.

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A simple spectrophotometric method, without solvent extraction, has been established for the determination of long-chain quaternary ammonium salts by ternary complex formation with o-hydroxyhydroquinonephthalein and manganese(II). The absorption maxima of the ternary complexes lay at about 575nm against water in borax media. In the case of hexadecylpyridinium chloride(HPC), Beer′s law held from 10 to 120μg/10ml, the apparent molar absorptivity and the coefficient of variation being 3.8×10⁴l mol^-1 cm^-1 and 0.59% (n=10) for 51μg of HPC.
In the determination of HPC, the coexistence of short-chain amines, such as triethanolamine and tetramethylammonium, and several basic drugs, such as thiamine and pyridoxine, interfered very little. This method was applied to the determination of long-chain quaternary ammonium salts in gargle and hair-rinse.

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A method for the determination of formaldehyde concentration in water is described. It is based on a coupling reaction of 1, 3-diphenyl-2-thiohydantoin with formaldehyde. In this reaction an anionic pigment is formed by addition of sodium hydroxide solution. The color intensity and formaldehyde concentrations were linearly related in the range up too 100μM. The minimum detectable concentration was 2μM. The precision (R.S.D.) was 3.62%.

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1, 4, 8, 11-tetraazacyclotetradecane(cyclam) gave two anodic waves (1:1) (E_1/2=-0.35 and -0.52V) in acetonitrile containing 0.1mol dm^-3 R₄NClO₄ (R=Et or Bu) or 0.05mol dm^-3Me₄NClO₄ as the supporting electrolyte at 25°C. With 0.1mol dm^-3 NaClO₄, the potential difference between two waves became small (E_1/2=-0.325 and -0.465V), and finally, with 0.1mol dm^-3 LiClO₄, the two waves were combined into a single anodic wave at E^1/2=-0.225V. The anodic waves of cyclam (L) with R₄NClO₄ were based on successive mercury dissolution reactions: L⁺Hg_??_[HgL]⁺_??_[HgL]²⁺. The process was reversible: the [HgL]²⁺ complex gave two cathodic waves on the DME at the same potential as the anodic waves from cyclam. The single anodic wave from cyclam in the presence of Li⁺ ions was attributed to the reaction: [LiL]⁺+Hg_??_[HgL]²⁺+Li⁺. The formation constant of [LiL]+ was evaluated (Li⁺+L_??_[LiL]⁺, log K=ca. 6.0) indirectly by the shift of the cathodic half-wave potential of [HgL]²⁺ to a positive direction with increasing concentration of Li⁺. Other voltammetric techniques, such as cyclic voltammetry or differential pulse polarography and coulometry, were also employed to elucidate the electrochemical process.

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A simple method for the determination of caffeine (1, 3, 7-trimethylxanthine) in plasma and urine is described. Caffeine was extracted by diethyl ether, together with spiked N-methylphenothiazine (NMPZ) as an internal standard. The amount was measured with gas chromatography (GC) using a nitrogen phosphorus-detector (NP-D). Almost 96% of the caffeine was recovered by diethyl ether. The detection limits of this assay were 1ng/ml of both in plasma and urine. Moreover, good linear relationships between peak height ratios and the concentrations of caffeine were found in the range 0 to 10μg/ml of plasma and 0 to 40μg/ml of urine, and reproducibility was kept within 3%. This method is rapid, sensitive and suitable as a routine method in the clinic.

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