We have developed a heatable flow cell system for in situ XAFS measurements that continuously observes chemical state changes in a sample containing a solution. The system was applied to the analysis of electroless nickel-phosphorus plating reaction to evaluate its applicability. The flow cell and the heater were provided with windows for passing X-rays, and 20 sheets of polyester film with a catalyst were enclosed in the cell. The electroless nickel-phosphorus plating solution was pumped into the cell with the heater temperature set at 60 °C, and nickel was deposited on the film in the cell. The change in the chemical state of nickel on the deposition reaction was observed by continuous Ni K-edge XAFS measurements (at BL28B2 in SPring-8) from the start of feeding the plating solution. As a result, it was found that nickel sulfate, which is the source of nickel in the plating solution used, changed to metallic nickel and nickel phosphide over time. In addition, the analytical results of the chemical state changes based on the in situ XAFS measurements were in good agreement with those based on the ex situ XAFS measurements of nickel and phosphorus. Therefore, this flow cell system is considered effective for continuous observation of the chemical state changes in a sample containing a solution.

The flavor volatiles released during the cooking of rice cultivars were analyzed online via resonance-enhanced multiphoton ionization time-of-flight mass spectrometry (REMPI-TOFMS) in real-time. As rice samples, Tanchomochi (glutinous rice) and Ichihomare (nonglutinous rice) were used; the final amount of water added was slightly reduced in the case of Tanchomochi because it has a higher ratio of water absorption. REMPI detected two volatile compounds, indole and 4-vinylphenol, during cooking at a wavelength of 266 nm. Indole was detected at a lower temperature in the case of Tanchomochi. This rice cultivar has lower swelling/gelatinization temperatures, which is considered the reason for the earlier leakage of indole (or its precursor) during the cooking of rice. In addition, the vaporization of indole proceeded even with the addition of a small amount of water during cooking. On the other hand, 4-vinylphenol was detected at the same temperature (a little less than 100 °C) in each sample, which could have been caused by the temperature of thermal decomposition from its precursor. Also, periodical increases and decreases in signals, due to steam repeatedly being released from a hole in the lid of the rice cooker, could be monitored at real-time via REMPI-TOFMS. This method can be used to elucidate the generation mechanism of flavor volatiles during cooking, which offers the possibility of tailoring cooking conditions to the differences in cultivar type and the milling percentage.

The determination of amino acids by gas chromatography-mass spectrometry (GC-MS) using a one-step derivatization with pentafluorobenzyl bromide (PFB-Br) in an aqueous acetone phase is described. Although GC-MS analysis of amino acids by pentafluorobenzyl (PFB) derivatization has been reported previously, its application to non-proteinogenic free amino acids, which play important biological roles in various metabolic pathways, has not been reported. In this study, 6 non-proteinogenic amino acids (sarcosine, 2-aminobutyric acid, 3-aminoisobutyric acid, β-alanine, 2-aminoadipic acid, and cystine) as well as 19 proteinogenic amino acids, with the exception of arginine, were PFB derivatized and analyzed by GC-MS using both electron ionization (EI) and positive-ion chemical ionization (PICI) modes. Two derivative peaks were observed for each amino acid with primary amino groups, which were identified as di- and/or tri-substituted derivatives (i.e., NH(PFB)-CHR-COO(PFB) or N(PFB)₂-CHR-COO(PFB)) based on their EI- and PICI-mass spectra. The ratio of the tri-substituted to the sum of the di- and tri-substituted derivative peaks was highest in glycine and β-alanine and lowest in branched amino acids, suggesting a dependence on steric hindrance around amino groups. Based on the identification of PFB derivative peaks, their retention indices on (5 % -phenyl)-methylpolysiloxane liquid phase capillary column, target and qualifier ions for selected ion monitoring (SIM) analysis on GC-EI-MS were determined to compile a quantification database.

The measurement and evaluation of the concentration of essential elements in hair, such as calcium iron and zinc, is known as a method for understanding the intake status of these elements that play an important role in the human diet. Analytical methods such as ICP-AES/MS are usually used for hair analysis but in this experiment we used X-ray fluorescence analysis as a simpler and faster measurement method. Furthermore, by applying the principle of the secondary target method we tried to detect X-ray fluorescence from trace elements in hair. In this experiment, a small amount of hair (0.3 mg) was lined up without gaps between the strands as a sample and 99.5 % pure SeO₂ powder, which served as a secondary target and was wrapped in a polymer film, was placed against the back of the hair. In addition to the usual primary X-rays we examined whether the excitation effect could be enhanced by fluorescent X-rays from the secondary target. As a result, the intensity of Zn Ca, and other elements in the hair was amplified by about 10 %. It was found that this method offers the possibility to detect trace elements (Zn, Ca) in hair with higher intensity nondestructively.

This study demonstrates that grain refinement of iron(III) hydroxide under alkaline conditions affects the chromium(III) removal efficiency of the coprecipitation method for chromium(VI) determination. After the addition of an FeNH₄(SO₄)₂ · 12H₂O solution to a simulated chromium solution, the pH was adjusted using a sodium hydroxide solution and chromium(III) was removed by filtration after heating and cooling the simulated solution. When the pH was in the range of 10.78-12.67 after heating and cooling, the chromium(III) removal efficiency decreased, causing a positive error for chromium(VI) determination. This may be because the iron (III) hydroxide precipitate undergoes grain refinement and passes through the filter because the iron concentration increased, and thereby the filtrates were colored. The addition of calcium chloride dihydrate facilitated the flocculation of the iron(III) hydroxide precipitate and increased the chromium(III) removal efficiency. The addition of calcium chloride did not affect the chromium(VI) recovery rate. When the pH was in the range of 8.95-13.07 after heating and cooling, the chromium(VI) recovery rate was over 90- % and the chromium(III) removal efficiency was over 98- %. Therefore, this method was confirmed to be suitable for chromium(VI) determination.

The method of analyzing carbonyl compounds by derivatization with 2,4-dinitrophenylhydrazine (DNPH) has been widely applied in various fields, and it entails the use of high performance liquid chromatography (HPLC) with ultraviolet/visible (UV/Vis) detection to identify and quantitate analytes. It is a very important issue with chromatography in the field of odor to separate structural isomers coexisting in a sample, because the odor of a substance arises from the molecular structure of the substance. Additionally, attention must be given to not only the structural isomers of the objects being measured but also the stereoisomers (syn/anti isomer) of the DNPH derivative in the separation of DNPH-derivatized carbonyl compounds. In this study, we examined HPLC measurement conditions for 6 aldehydes of specified offensive odor substances defined by the Offensive Odor Control Law in Japan, and confirmed the validity of the measurement method. In the experiment, 18 carbonyl compounds-DNPH mixed solution containing both syn-isomer and anti-isomer of DNPH derivatives was used as the simulated sample of the eluate from gas-collected DNPH cartridge. The result of the examination revealed that all of the 6 aldehydes were sufficiently separated by using a C8 column. According to the verification of the measurement data under optimized condition, it was shown that linear standard curves were obtained in the concentration range of 0.05 μg mL⁻¹ - 1 μg mL⁻¹, and the reliability of analysis values was secured. Furthermore, the measurement method established in this study was applied to the exhaust gas from an industrial plant, and the effect of each aldehyde on the odor around the plant was considered.

Rapid analytical method for the determination of Zr-93 in radioactive wastes has been developed. Laser ablation (LA)–ICP–MS was applied to the analysis of Zr isotopes in simulated high-level radioactive waste (HLW). Sample preparation time was dramatically reduced by using a DGA resin as the adsorbent for Zr. Direct quantification of Zr isotopes in this resin sample was carried out by LA–ICP–MS. Laser settings were optimized to obtain a reliable isotope ratio of the sample by LA–ICP–MS. Quantification of Zr isotopes in the simulated HLW solution by isotope dilution mass spectrometry (IDMS) was examined. The amount of Zr-90 in the sample obtained by IDMS corresponded to a value calculated from the given concentration of Zr in the sample within uncertainty. Thus, this method can be applied for the quantification of Zr-93 in radioactive wastes.

Unreacted urea remaining after the reaction of urea with formaldehyde was converted to ammonia using immobilized urease. The quantity of ammonia produced was measured using IC, thus, the remaining formaldehyde was indirectly quantified. The immobilized urease was prepared by the adsorption of urease on woody and herbaceous biomass modified with polyamine. The activity of the immobilized urease was the highest in cedar (53.8 U mg⁻¹), followed in descending rice (40.4 U mg⁻¹), kenaf (34.0 U mg⁻¹), and beech (11.5 U mg⁻¹). A fixed quantity of urea was reacted with formaldehyde in the presence of hydrochloric acid. Unreacted urea was passed through an IC-FIA system connected to the immobilized urease column and the ammonia produced from the urea was measured. The calibration curves of formaldehyde were linear (r = 0.9968) over 1.0-5.0 mg, therefore, formaldehyde could be quantified. The determination of formaldehyde was affected by acetaldehyde, but not by other aldehydes.

This study provides analyses of the Atomic Force Microscope (AFM) rupture length, which is the longest distance in the Z-direction where the adhesion is obtained by release force curves. Clear XY rupture length images were obtained from the results. In this paper, we showed that there is a difference in the distribution of adhesion force vs rupture length plot on the surface of silica particles with different surface treatment materials, and that clear rupture length images of LiB binder and polymer film with a sea-island structure could be obtained. From these, we concluded that the AFM rupture length can be a valid parameter for material surface as well as the adhesion force.

The fsLA-ICP-MS, which combines the femtosecond laser-based ablation sampling technique and inductively coupled plasma-mass spectrometry, has attracted attention as a sensitive and rapid analytical technique for major- to trace-elements in various solid materials. With the fsLA-ICP-MS technique, elemental analysis can be conducted without complicated and time-consuming chemical preparation procedures utilizing hazardous reagents such as nitric, chloric, or hydrofluoric acids. More importantly, the technique is capable of ultra-high-sensitivity analysis without the need to remove the solvents through drying procedures, obviating the risk of contamination of elements from environments or laboratory equipment. Despite the unique features of the technique, precise and accurate element determinations can be impeded when no reference or calibration standard is available. There are no organic based calibration standard samples suitable for quantitative analysis by fsLA-ICP-MS, especially none that target very few and various elements. To overcome this, we have developed new organic based calibration standard materials containing 18 elements of various concentrations ranging from 0.1 to 100 mg kg⁻¹. In this study, the analytical capability of the present calibration materials was rigorously tested through elemental analyses on glass and polymer materials using the fsLA-ICP-MS technique.