金属ナノ粒子は最近特に注目を集めているナノ材料の一つである．金属ナノ粒子，特に金のナノ粒子は高い発色性，安定性という分析化学の要件を満たし，顕微鏡マーカーや診断キットなどの広い分野で使用されてきた．また，化学センシングの分野においても最近10年間に新しい技術が数多く報告されている．このように金属ナノ粒子は分析化学にとって必要不可欠な材料となりつつあるが，この論文では特に金ナノ粒子の分析化学的応用に関して現状と課題，将来展望について解説する．まず，金ナノ粒子の持つ特徴を解説し，増感機能，電子的特異機能の発現に着目して論ずる．更に，最近注目されている分子デバイスの作製に対する展望についても解説する．

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石炭中には周期表中のほとんどの元素が幅広い濃度範囲で取り込まれており，現在84元素の存在が確認されている．これらの元素のうちmg kg⁻¹オーダーで含まれる元素について，高圧酸素下での燃焼による固体試料の分解と誘導結合プラズマ質量分析（ICP-MS）を組み合わせて，迅速かつ精度よく同時定量できる方法を確立した．粉末にした石炭試料300 mgと助燃剤としてのデンプン600 mgの混合物を燃焼用試料とし，5 mLの5% 硝酸-1% 過酸化水素を入れたボンブ内で，3 MPaの高圧酸素下で燃焼させる．石炭中の元素は酸化物となり，酸性溶液中に溶解して石炭から回収される．この溶液をA過•希釈してICP-MS測定用溶液とする．NIST SRM 1632b，1632cを標準試料として用い，ReとRhによる内部標準法で定量を行ったところ，V，As，Se，Cd，Ba，Pbの6元素において認証値とよく一致した．本研究における定量値は，マイクロ波酸湿式分解法-ICP-MSによる同試料の定量値ともよく一致した．この方法を実試料に応用し，産炭地の異なる20種類の石炭中6元素（V，As，Se，Cd，Ba，Pb）の存在度を求めた．

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基板上に多数の微小帯電極をある一定の間隔で平行に配置した集合微小帯電極（縞電極又は縞状電極と略称）について，パルス•ボルタンメトリーにおける電流応答特性，特にその高い信号対雑音（signal-to-noise）特性に注目し検討した．実験にはリソグラフィー技術を用いて作製した2種類の金縞状電極（幅30 μm，間隔30 μm，及び幅10 μm，間隔50 μm），また比較のため通常の金平板電極を使用した．フェリシアン化カリウム（還元波）とフェロシアン化カリウム（酸化波）において，縞電極で得られる限界電流値は理論式に対応した挙動を示し，電解時間（サンプリング時間）の経過とともに基板と同面積の平板電極での限界電流値に近づくことが確認された．10^－6 Mオーダーでの検量線から，基板面積に占める電極表面積の割合が減少するに従い，縞電極の基底電流値は減少し，検出限界の向上が確認できた．

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Simple liquid chromatography by capillary action using a monolithic silica rod and a capillary as the separation media instead of a thin-layer plate in conventional thin-layer chromatography (TLC) was examined. Possibilities of this chromatography were demonstrated by the separation of some organic compounds. Monolithic silica rod and capillary are very handy and useful as separation media for simple open liquid chromatography.

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A simple and fast field method was developed for the determination of leachable Cr(VI) in soil by ultrasonic extraction and colorimetry with 1,5-diphenylcarbonohydrazide. Extraction from 2.0 g of a sample with 20 mL of water was accomplished with 30 min under ultrasonication (46 kHz, 15 W). The extraction was repeatable with a relative standard deviation of 10%. The extraction characteristics were discussed based on elution kinetics. The water-leachable concentrations of Cr(VI) or the total Cr were comparable to those obtained by the shaking extraction (6 h) used in Notification 46 of Environmental Agency of Japan. A detection limit of 0.003 mg/L was obtained by a laboratory-made colorimeter with a RGB light-emitting diode. The proposed method is applicable for soil samples containing no Cr(VI)-reducing matters, e.g., humic substances.

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The chemical degradation method of polyester-polyurethanes using a high-frequency heating technique was investigated. Model polyester-polyurethanes were prepared from 4,4'-dicyclohexylmethane diisocyanate (H12MDI), poly(butylene adipate) or poly(ethylene adipate)-polyols and isophoronediamine as a chain extender. The number-average molecular weights of their polyesterpolyols were 3500 Da. Phenylisocyanate was an effective reagent to decompose the urethane bond selectively without cleaving the ester bond. After 30 mg of a polyurethane sample was heated at 255°C in a mixture of phenylisocyanate in a sealed glass tube, the urethane bond was decomposed after 30 minutes under this condition. After the reaction, the molecular weight and the composition of the polyesterpolyols were determined by MALDI TOF-MS and SEC. The separation between the peaks of the main series consisted with repeated polyesterpolyols units. The ions consisted of a polyester chain with N -phenylurethane terminal groups from MALDI spectra. SEC chromatograms of degraded samples were consistent with the model N -phenylurethane-terminated polyester. The combination of selective degradation with SEC, MALDI and a high-frequency heating technique, using phenylisocyanate, is a viable method for easy and quick polyurethane polyol characterization.

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In this study, we carried out measurements of genotoxic organics, i.e. 11 kinds of polycyclic aromatic hydrocarbons (PAHs), 8 kinds of nitrated polycyclic aromatic hydrocarbons (NPAHs), and 3-nitrobenzanthrone (3-NBA), in diesel-engine exhaust particles (DEP) from combustion processes of biodiesel fuel (BDF) synthesized from vegetable oils, petroleum diesel fuel, and their mixtures. All PAHs and NPAHs in the DEP collected decreased with increasing the content of BDF in the fuel. The reduction rates of PAHs and NPAHs emitted from the diesel-engine by replacing the PDF to BDF were in the range from 44 to 89%. While the reduction rate of 3-NBA, which is one of the oxy-aromatic compounds, was lower than those of PAHs and NPAHs, it was only 20%. PAHs can be generated by the cyclization and/or polymerization of hydrocarbons, especially of aromatic hydrocarbons, when fuels incompletely burn. However, BDF containing 20 vol.% of benzene showed no increase of PAHs and NPAHs emission compared to the BDF without benzene through the fuel-combustion process. This fact indicates that the drastic reduction of PAHs and NPAHs by using BDF is not due to the content of aromatics in the fuel, but the high oxygen content in its molecular structures. The mutagenic activity of the soluble organic fraction of the DEP also remarkably decreased with increasing of the BDF contents in the fuel. It is apparent from the results that BDF is a quite effective alternative fuel to reduce the genotoxic potentials of DEP.

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An evaluation system for the water environment of a river basin (Web-EGIS) has been developed based on a geographic information system. The environmental data were constructed on the Web-EGIS server, enabling us to show the spatial and seasonal variations of the data from client computers via the internet web system. The system also can simultaneously indicate land-utilization information map around the river basin together with the environmental data. This Web-EGIS was applied to the Ongagawa River basin located on the northern part of Kyushu Island, Japan. Spatial and seasonal variations of the environmental data originated from nature and from human activities could be clearly distinguished. The exact pollution point into river water could be specified by using the Web-EGIS system.

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The Japan Society for Analytical Chemistry carried out proficiency testing for a fourth-round determination of dioxins (polychlorodibenzo-p-dioxins, polychloro-dibenzofurans and dioxin-like polychlorobiphenyls) in the combustion dust of a waste incinerator. This proficiency testing of analytical laboratories is based on ISO/IEC Guide 43-1, "Proficiency testing by interlaboratory comparisons". The testing was carried out from June '03 to August '03, with the participation of 117 laboratories. As a result, 107 laboratories (91.5%) were estimated as being "satisfactory", 6 laboratories (5.1%) as "questionable" and 4 laboratories (3.4%) as "unsatisfactory". A tendency was found that the determined values of the toxicity equivalent quantity became large when an SP 2331 liquid phase or the like was applied to the capillary column of the gas chromatograph. This may have come from insufficient separation of some components.

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The Japan Society for Analytical Chemistry carried out a fifth proficiency testing for the determination of dioxins (polychlorodibenzo-p-dioxins, polychlorodibenzofurans and dioxin-like polychlorobiphenyls) in the combustion dust of a waste incinerator. This proficiency testing of analytical laboratories is based on ISO/IEC Guide 43-1, "Proficiency testing by interlaboratory comparisons". This testing was carried out from June '04 to August '04, with the participation of 118 laboratories. As a result, 107 laboratories (91%) were estimated to be "satisfactory", 6 laboratories (5%) as "questionable" and 5 laboratories (4%) as "unsatisfactory". The results indicated a tendency that the determined values of the toxicity equivalent quantity became large in the case of applying SP 2331 or CP Sil-88 liquid phases to the capillary column of a gas chromatograph. This may have come from insufficient separation of 1,2,3,7,8-PeCDF, and of 1,2,3,4,7,8-HxCDF from other components.

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