ペプチド等の生体由来成分の無標識高感度分離分析を目的として，励起光に波長266 nmの紫外光を有する紫外励起熱レンズ顕微鏡（UV-TLM）と液体クロマトグラフィー（LC）を組み合わせた測定システム（LC/UV-TLM）を構築した．構築したシステムの性能を評価するために，グラジエント溶出法を適応した際の熱レンズ信号に対する影響を検討した．熱レンズ信号は溶媒によって信号強度が大きく変化するため，グラジエント溶出法のような溶媒組成が時間とともに変化するような系では，その影響を検討する必要がある．水-アセトニトリル系グラジエントにおいては，アセトニトリルの体積分率が40% 未満では，熱レンズ測定に大きな影響を及ぼさないということが分かった．標準試料を用いてLC/UV-TLMの検出性能を評価したところ，通常の分光光度計を検出器としたシステムに比較して10倍以上高感度であることが分かった．

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ブナおが屑をホスホン酸ジフェニル-ホルムアルデヒド樹脂で化学修飾して発煙硫酸処理に耐えられる木質バイオマス-合成高分子複合体を合成して，これを基体とするスルホン酸基を有する強酸性陽イオン交換樹脂を得た．ブナおが屑を強化するのに必要なホスホン酸ジフェニル樹脂は原料の仕込み濃度で約14 wt% 以上あれば十分であり，原料仕込み濃度で約75 wt% ブナおが屑を基体とするスルホン酸基を有する強酸性陽イオン交換樹脂を得ることができた．交換容量は2.4 meqg⁻¹-R（乾燥樹脂）と良好な値であり，交換速度も速く約5分以内で平衡に達し，そのため高速でのイオン交換が可能であった．密度は1.18 g mL⁻¹ であり，水溶液中で浮くという欠点もなくカラム操作に十分に対応できるイオン交換樹脂であった．本交換樹脂は塩酸溶液あるいはメタノール-塩酸混合溶液を用いると，Li⁺-K⁺，Mg²⁺-Ca²⁺-Sr²⁺-Ba²⁺の相互分離，更にはCd²⁺-Zn²⁺，Cd²⁺-Co²⁺あるいはCd²⁺-Ni²⁺などの相互分離に利用できた．

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日本分析化学会はダイオキシン類分析用排水標準物質作製委員会を組織し，ポリクロロジベンゾパラジオキシン（PCDD）6異性体，ポリクロロジベンソフラン（PCDF）10異性体，PCDD及びPCDFの四∼八塩素置換同族体，並びにダイオキシン様ポリクロロビフェニル（DL-PCB）6種の含有率を認証した排水認証標準物質を開発した．施設排水は浮遊物質を含む不均一系であり，ダイオキシン類はそのほとんどが懸濁粒子に吸着しているため，均一な組成を前提とする標準物質の作製には不適としてこれまでダイオキシン類分析用の排水標準物質の前例はない．そこで，1個の容器内標準物質は全内容を1回で使い切ることを前提とし，排水の容器へのサンプリング方法を検討することにより世界初の排水認証標準物質を開発することに成功した．ダイオキシン類29異性体の認証値は26試験機関の参加による共同実験の結果から異常値を除外した後統計的に処理してその不確かさとともに求めた．なお，この認証標準物質のダイオキシン類の合計濃度は毒性当量にして13.8±0.6 pg L⁻¹である．

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金コロイド標識した抗カドミウム-エチレンジアミン四酢酸錯体（Cd-EDTA）モノクローナル抗体を用いて，米中のカドミウムを簡便•迅速に定量できるイムノクロマトグラフィーを開発した．作製した抗Cd-EDTA抗体（Nx2C3）のCd-EDTAとの平衡解離定数は1.3 × 10⁻⁸ Mであり，検討した他の金属のEDTA錯体の平衡解離定数（9.6 × 10⁻⁷ M以上）とは70倍以上の違いがあった．米中のカドミウムを本イムノクロマトグラフィーによって測定するための前処理として，希塩酸によるカドミウムの抽出，並びにカラム処理による共雑金属の除去を検討した．その結果，イムノクロマトグラフィーの測定に影響しうる亜鉛，マンガン，マグネシウムなどの金属を排除しつつ，米中のカドミウムをほぼ完全に抽出•精製できることが分かった．また，構築したイムノクロマトグラフィーにおけるカドミウムの測定範囲は0.01 mg L⁻¹から 0.1 mg L⁻¹であった．50検体の玄米試料を上記前処理に施した後，本イムノクロマトグラフィーによってカドミウム濃度を測定した．本法で測定した米中のカドミウム含量は，硝酸分解による前処理と誘導結合プラズマ発光分析装置を用いた測定結果と良い相関（r = 0.94）を示した．

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Silver o-ethylphosphonate was prepared by the reaction of diethylphosphonate with silver nitrate for 8 h in acetonitrile below 10°C. This compound decomposed in alcoholic potassium hydroxide to form silver(II) oxide and ethylphosphonate in the intermediate. When no reducing reagent existed, silver(II) oxide was reduced by ethylphosphonate to deposite silver, which formed a silver film on the glass base. When a reducing reagent existed, it was oxidized by silver(II) oxide. Benzaldehyde and its derivatives with an electron-withdrawing substituent were oxidized to convert corresponding carboxylic acid in a yield of over 90%. This oxidoreduction occurred at room temperature, and finished within 10 minutes. The oxidation reaction of benzaldehyde by silver o-ethylphosphonate could be utilized for the removal of benzaldehyde contained in a liquid aromatic compound. Benzaldehyde <2 v/v% contained in toluene could be removed in a single oxidation reaction, and of 20 v/v% in the operation performed four times.

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We performed a space-time imaging analysis of a single colony of marine luminous bacterium using a fluorescent microscope connected to a real-color CCD camera. The bioluminescence and bright-field imaging showed that a glowing ring occurred close to the frontline of the growing colony, and that the ring spread out regularly while retaining a concentric ring shape. The glowing ring faded out when the colony terminated its growth. Furthermore, it was found that either aeration or O₂-supply triggered a new glowing ring on the dim inside of the colony, and that the newly triggered ring phases out in the absence of aeration or O₂-supply. Such a flickering pattern was confirmed to repetitively occur on the same concentric circle, corresponding to the presence and absence of aeration or O₂-supply. From these findings, it is postulated that a growing single colony possesses a certain periodic property.

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The lanthanoids in shell of shellfish were determined by ICP-MS. The intensities of lanthanoids were very highly suppressed by large amounts of calcium ions, which made their determination difficult. It was necessary to separate any lantanoids from calcium. We applied the solvent-extraction method to separate the lanthanoids from the interfering calcium. The chelating agent was easy to form the chelate for lanthanoids; then, a reagent that could extract the chelate from the acid solution was chosen. 1-phenyl-3-methyl-4-trifluoroacetyl-5-pyrazolone (HPMTFP), in which the pK_a value was 2.56, was chosen as the extraction reagent. Hard tissues of shell used in the present work were treated with inorganic acids. Lanthanoids were extracted with 0.01 mol/l-HPMTFP in diisobutyl ketone at pH 2 in order to separate it from the interfering calcium. The organic solvent, including the chelate, was decomposed in inorganic acid, and was made to be an aqueous solution. Lanthanoids in the solution were determined by ICP-MS. The lanthanoids content in the shell was found to be 0.82∼124 ng/g.

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Ultrafine particles of TiO₂ were prepared by the hydrolysis of titanium tetrachloride (TiCl₄) in a highly concentrated hydrochloric acid aqueous solution at a low temperature, in which the surfacing modifier did not coexist. The absorption spectrum of the prepared TiO₂ ultrafine particle showed a blue shift, which was more remarkable than that of a bulk sample. The fluorescence of the prepared TiO₂ fine particles confirmed being within the ultraviolet wavelength range with a peak at 370 nm by changing the excitation wavelength from 220 nm to 300 nm. The bulk TiO₂ of Rutile and Anatase type showed light absorption in proportion to the transition of inter-bands at 413 nm (3.0 eV) and 388 nm (3.2 eV), respectively. Because the excitation wavelength of 230 nm corresponds to 5.4 eV, it is converted into the band energy. The size of TiO₂ identified from a laser scatter measurement was 3.5±1.0 nm, which was confirmed to be the size at which a quantum size effect appears. From the XRD measurement, secondary fine particles (aggregate) of TiO₂ after separation by a membrane filter was identified to be of the Rutile type. The size of the (110), (101) and (211) crystal planes were estimated to be 5.3, 8.0 and 5.1 nm by an evaluation using the Scherrer equation for the half-value width of the diffraction peak of each crystal plane. The shape of the aggregate observed from the SEM image was tabular, of μm size. It was concluded that TiO₂ fine particles with a hierarchy of sizes from nm to mm were possible by the low-temperature hydrolysis of TiCl₄ in a high concentration of hydrochloric acid aqueous solution. Application to an ultraviolet ray protective agent for UVC, UVB and UVA is expected in the future.

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Anode catalysts for a fuel-cell system were evaluated by employing a porous microelectrode technique in a 0.5 mol dm⁻³ H₂SO₄ aqueous solution. An anodic current for carbon monoxide (CO) oxidation was observed under a 1000 ppm-CO-containing hydrogen atmosphere, in which the onset potential based on CO oxidation at Pt-Ru/C shifted toward cathodic direction from that at Pt/C. In a measurement of CO-stripping voltammetry, the onset potential of CO oxidation well agreed with that of CO-containing hydrogen at Pt-Ru/C. However, in the case of Pt/C, the onset potentials were not the same. This suggests that the CO adsorptions at Pt/C and Pt-Ru/C were different in terms of energetics.

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