Vol. 13, Supplement B (1997)

Proceedings of the 25th Chemical Sensor Symposium
September 10-11, 1997

Abstracts

1.

アニリンオリゴマ-被覆カ−ボン電極の作製とカテコ−ルアミンの電流応答

前田裕司*、吉田泰彦*、長谷部靖**、内山俊一**

東洋大工*、埼玉工大工**

FABRICATION OF ANILINE OLIGOMER COATED CARBON ELECTRODE AND ITS CURRENT RESPONSES FOR CATECHOLAMINES

Yuji MAEDA*, Yasuhiko YOSHIDA*, Yasushi HASEBE**, and Shunichi UCHIYAMA**

*Department of Applied Chemistry, Faculty of Engineering, Toyo University
2100Nakanodai,Kujirai,Kawagoe,Saitama350
**Department of Environmental Engineering, Faculty of Engineering, Saitama Institute of Technology
1690, Fusaiji, Okabe, Saitama 369-02, Japan

Three reversible redox waves (E0 = + 0.10 V, - 0.05 V, - 0.18 V vs. SCE) of oxidation products of aniline appear at a neutral pH range other than the oxidation wave of aniline in the cyclic voltammogram of high concentration of aniline obtained by a porous carbon felt. The third and the fourth waves also appeared in the cyclic voltammogram of mixture of 4-aminodiphenylamine and aniline. Under nitrogen atmosphere, the wave height appeared at the oxidation of dimer (IIa) was equal to the summation of IIc (the reduction wave of dimer), 2IIIc(the reduction wave of trimer) and 3IVc (the reduction wave of tetramer). This fact indicates that the third and fourth redox waves correspond to the redox reaction of trimer and tetramer of aniline. The electroactive couple of the fourth wave is gradually accumulated by adsorbing to the surface of the carbon electrode during repetitive cyclic voltammetry and it was found that tetraaniline modified carbon electrode can be prepared by the cyclic voltammetry of 4-aminodiphenylamine in aniline solution at pH 7. This tetraaniline modified carbon fele electrode has been applied to separative determination of catecholamines, especially, epinephrine and dopamine. The principle of separation is that dopaminequinone react with aniline, producing an adduct although epinephrinequinone does not form an adduct because its cyclization rate is much higher than that of dopamine.

To Japanese Contents To English Contents
2.

カテコールアミンキノンのアニリン付加体のカーボン電極における選択的な電流応答

内山俊一、長谷部靖、西本次郎

埼玉工大工

SELECTIVE CARBON ELECTRODE CURRENT RESPONSES OF ADDUCTS FORMED BETWEEN CATECHOLAMINES AND ANILINE

Shunichi UCHIYAMA, Yasushi HASEBE, Jiro NISHIMOTO

Department of Environmental Engineering, Faculty of Engineering, Saitama Institute of Technology
1690 Fusaiji, Okabe, Saitama 369-02, Japan

The catecholaminequinones cyclize by nucleophilic substitutions of amino group of a side chain and indole compounds are formed. However, aniline can interfere these cyclizations and catecholaminequinone-aniline adduct is produced if nucleophilic substitution rate is slow. These adducts exhibit reversible redox waves at the potential range between the redox potential of catecholamine and that of indole compound. The cyclization rates of catecholamines are rather different each other and, consequently result in being able to obtain separative redox waves. Especially, the complete separation of redox waves of dopamine and epinephrine can be realized by using aniline in cyclic voltammetry because the cyclization rate of epinephrine are much higher than that of dopamine.

To Japanese Contents To English Contents
3.

リン酸エステルを用いた有機アンモニウムイオン電極の開発

勝　孝、徐　達峰、辻　琴代、永松朝文

岡山大薬

ORGANIC AMMONIUM ION-SELECTIVE MEMBRANE ELECTRODE BASED ON PHOSPHATE ESTER

Takashi KATSU, Dafeng XU, Kotoyo TSUJI, and Tomohisa NAGAMATSU

Faculty of Pharmaceutical Sciences, Okayama University

Tsushima, Okayama 700, Japan

We found that the phosphate esters, such as tris(2-ethylhexyl) phosphate (TEHP) and tricresyl phosphate, can be used as neutral carriers to make organic ammonium ion-selective membrane electrodes. For example, a hexylammonium ion-selective electrode was constructed using TEHP as the carrier and dioctyl phthalate as a membrane solvent in a poly(vinyl chloride) membrane matrix. The electrode exhibited a near-Nernstian response to hexylammonium in the concentration range from 2 x 10-4 to 1 x 10-1 M with a slope of 57 mV per concentration decade. The lower limit of detection was 2 x 10-5 M. This sensitivity was comparable to that of the electrode made from one of the amine ionophores, a calix[6]arene analog, reported previously. The interaction between the phosphate ester and hexylammonium was confirmed by 1H-NMR spectroscopy.

To Japanese Contents To English Contents
4.

シアン計測用応答阻害型バイオセンサー

立間　徹、小川高史、小山　昇

東京農工大工

INTERFERENCE-BASED BIOSENSORS FOR THE DETERMINATION OF CYANIDE

Tetsu TATSUMA, Takashi OGAWA, and Noboru OYAMA

Department of Applied Chemistry, Faculty of Technology, Tokyo University of Agriculture and Technology

Koganei, Tokyo 184, Japan

Pyrolytic graphite (PG) electrodes on which horseradish peroxidase (HRP) is adsorbed are examined as cyanide biosensors. Cyanide is determined on the basis of inhibited H2O2 reduction current, which is catalyzed by HRP. In the case where the H2O2 concentration is so low that most HRP molecules exist as ferric HRP, sensitivity of the cyanide sensor depends on the surface coverage of HRP. The sensor respond to cyanide even when the H2O2 concentration is so high that most HRP molecules exist as compound I or II, though the sensitivity poorly depends on the HRP coverage.

To Japanese Contents To English Contents
5.

多孔性金属電極への複数酵素の固定化によるマルチ酵素センサの作製とその特性

碇山義人、橘　亜樹*、外山　滋、吉田泰彦*

国立リハビリ研、東洋大工*

FABRICATION OF MULTI-ENZYME SENSOR BY IMMOBILIZING ENZYMES TO POROUS METAL ELECTRODE AND ITS CHARACTERISTICS

Yoshihito IKARIYAMA, Aki TACHIBANA, Shigeru TOYAMA, Yasuhiko YOSHIDA

Research Institute, National Rehabilitation Center for the Disabled
4-1 Namiki, Tokorozawa 359, Japan
*Department of Applied Chemistry, Faculty of Engineering, Toyo University
2100 Kujirai, Kawagoe 350, Japan

An amperometric urea sensor using urease, glutamate dehydrogenase (GLDH) and glutamate oxidase (GLOx), was fabricated. First, bi-enzyme electrode, where GLDH and GLOx were immobilized, was examined. Then tri-enzyme electrode was investigated; Tri-enzyme electrode showed the increase in current upon the addition of ammonia. In addition, the tri-enzyme electrode showed the increase in current upon the addition of urea.
To Japanese Contents To English Contents
特別講演1.

電気化学的簡易遺伝子検出法（遺伝子センサ）の開発

石森 義雄

（株）東芝

DEVELOPMENT OF AN ELECTROCHEMICAL EASY DNA DETECTION METHOD（DNA SENSOR）

Yoshio ISHIMORI

Environmental Engineering Department，Research and Development Center，Toshiba Corporation
1 Komukai Toshiba-Cho，Saiwai-ku，Kawasaki 210, Japan

An electrochemical easy DNA detection method (DNA sensor) has been developing for the measurement of hepatitis B virus(HBV) in human sera．The DNA Sensor us es a three-step process to determine the concentration of HBV． First， oligonucleotides(DNA probes) immobilized on the gold electrode of the DNA sensor selectively catch HBV DNA． Second，a DNA intercalator (Hoechst 33258) acting as an electrochemical signal amplifier reacts with the DNA hybrids formed on the electrode． Third，the current signal from the intercalator is measured． A correlation coefficient of 0.75 was obtained between the 52 patients' data from the DNA sensor and those from the competitive polymerase chain reaction（PCR）method (10E3-10E8 copies/40μL)．

To Japanese Contents To English Contents
6.

集積型微小酵素センサを用いた乳酸発酵のオンラインモニタリングシステム

鈴木正康、熊谷剛史、藤岡潔、清水和幸

九工大情報工

ON-LINE MONITORING SYSTEM OF LACTIC ACID FERMENTATION BY USING THE INTEGRATED ENZYME SENSORS

Masayasu SUZUKI, Takeshi KUMAGAI, Kiyoshi FUJIOKA, and Kazuyuki SHIMIZU

Department of Biochemical Engineering and Science, Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology
Iizuka-shi, Fukuoka 820, Japan

On-line monitoring system for lactic acid fermentation was developed by using the integrated micro enzyme sensors, a flow injection analysis system and the micro dialysis system. The calibration curves of micro glucose, lactose and lactate sensors showed the good linearity in the concentration range below 50 - 70mM. By the combination with the micro dialysis system, the enzyme sensors could measure the whole concentration range of lactic acid fermentation, and the interference by the medium could not be observed. The on-line sensor system was then applied to the lactic acid fermentation of Lactobacillus delbrueckii. The sensor system could monitor the glucose and lactate concentration simultaneously during the 24-h fermentation, and the measurements showed good agreement with those of the conventional colorimetric method.

To Japanese Contents To English Contents
7.

Con A/LOx累積膜を用いた乳酸センサ

小林由佳、中村伸之、安斉順一

東北大薬

LACTATE SENSORS BASED ON Con A/LOx MULTILAYER-MODIFIED ELECTRODES

Yuka KOBAYASHI, Nobuyuki NAKAMURA and Jun-ichi ANZAI

Faculty of Pharmaceutical Sciences, Tohoku University
Aobayama, Sendai 980-77, Japan

Protein multilayers composed of concanavalin A (Con A) and lactate oxidase (LOx) were prepared on the surface of a platinum electrode to construct electrochemical enzyme sensors sensitive to L-lactate, by means of a specific affinity between Con A and mannose. For this purpose, LOx was modified with mannose residues covalently by treating with an excess amount of 4-isothiocyanatephenyl-a-D-mannopyranose. By this treatment LOx was tagged with several residues of mannose. Con A and the mannose-modified LOx were deposited on the surface of a platinum electrode alternately, by immersing the electrode in the solutions of Con A and enzyme. It was found that Con A/LOx multilayers are formed in this simple procedure. A gravimetric study using a quartz-crystal microbalance and a spectrophotometric study also suggested a formation of the Con A/Lox multilayers. The Con A/LOx multilayer-modified electrodes exhibited an amperometric response to　10-6 - 3x10-2 M L-lactate, the size of the output current being dependent on the number of the enzyme layers.

To Japanese Contents To English Contents
8.

コレステロールオキシダーゼ、およびエステラーゼを固定した電極のアンペロメトリック応答

中南貴裕、伊藤慎一郎、桑畑　進、米山　宏

阪大院工

AMPEROMETRIC RESPONSE OF CHOLESTEROL OXIDASE- AND ESTERASE- IMMOBILIZED ELECTRODES TO FREE AND ESTERIFIED FORM OF CHOLESTEROL

Takahiro NAKAMINAMI, Shin-ichiro ITO, Susumu KUWABATA, and Hiroshi YONEYAMA

Department of Applied Chemistry, Faculty of Engineering, Osaka University
2-1 Yamada-oka, Suita, Osaka 565, Japan

Cholesterol oxidase (ChOx) and cholesterol esterase (ChE) were immobilized onto an Au electrode substrate which was covered by a self-assembled monolayer of cystamine. The resulting enzyme-electrode (ChE/ChOx/Au) exhibited amperometric response to free and esterified form of cholesterol in the presense of electron mediator for ChOx, ie thionin. It was found that the ChE/ChOx/Au electrode possesses much larger apparent Michaelis constant for cholesterol than native-ChOx. The comparison of the amperometric responses between two kinds of electrodes revealed that co-immobilization of ChE with ChOx gave higher sensitivity as compared to the immobilization of ChOx alone. Encapsulation of thionin in the enzyme layer on the electrode substrate was suggested from hydrodynamic voltammetry using the ChE/ChOx/Au electrode.

To Japanese Contents To English Contents
9.

電極／ポリイオンコンプレックス膜／酵素膜の構成のグルコースセンサ

水谷文雄、佐藤　縁、澤口隆博、矢吹聡一

生命工研

AMPEROMETRIC GLUCOSE SENSOR USING A POLYION COMPLEX-ENZYME BILAYER SYSTEM

Fumio MIZUTANI, Yukari SATO, Takahiro SAWAGUCHI, and Soichi YABUKI

National Institute of Bioscience and Human-Technology
1-1 Higashi, Tsukuba, Ibaraki 305, Japan

An amperometric glucose-sensing electrode was prepared as follows. First, a gold electrode was modified with mercaptopropionic acid (MPA) by soaking the electrode in an alcohol solution containing MPA. Then an aqueous solution containing poly-L-lysine and that containing poly(4-styrenesulfonate) was successively placed on the electrode surface to form a polyion complex layer, and the solvent was allowed to dry. Finally, an enzyme layer was formed on the polyion complex layer by placing a glucose oxidase (GOx) solution and a glutaraldehyde solution and drying. The modification of the gold surface with MPA was effective for enhancing the adhesiveness of the polyion complex layer to the base electrode owing to the electrostatic interaction between the amino groups of poly-L-lysine and the carboxylic groups of MPA molecules on the electrode. The amino groups of poly-L-lysine were also be useful for immobilizing GOx molecules. The phdrophilicity and permoselectivity of the polyion complex membrane were effective in obtaining a rapid response for glucose (100% response time, 5 s) and low interferential levels (e.g., the ratio of response for L-ascorbic acid to that for the same concentration of glucose, 0.07).

To Japanese Contents To English Contents
10.

電析白金/ポリイオンコンプレックス複合電極を用いたグルコースセンサの作製

駒場慎一，奥村壮文，目黒正大，逢坂哲彌

早大理工・早大材料技術研

FABRICATION OF AMPEROMETRIC GLUCOSE SENSOR BASED ON THE COMPOSITE FILM OF ELECTRODEPOSITED PLATINUM WITH POLYION COMPLEX.

Shinichi KOMABA, Takefumi OKUMURA, Masahiro MEGURO, and Tetsuya OSAKA

Department of Applied Chemistry, School of Science and Engineering; Kagami Memorial Laboratory for Materials Science and Technology, Waseda University
Shinjuku-ku, Tokyo 169, Japan

Amperometric glucose sensors were fabricated by use of the composite film consisted of the polyion complex (PIC) containing glucose oxidase (EC 1.1.3.4.) and the electrodeposited platinum. The Pt/PIC composite film electrode demonstrated higher current response to glucose and wider detection range than those of only PIC film electrode. We investigated the dependence of the conditions of the electrodeposition on response characteristics.

To Japanese Contents To English Contents
11.

高分子修飾電極を用いた新規グルコ−スセンサ−：ケモメトリックス手法による最適化

孫立賢、除芬、岡田達弘

物質工学工業技術研究所

NEW GLUCOSE SENSOR BASED ON POLYMER MODIFIED ELECTRODES OPTIMIZED BY CHEMOMETRICS METHOD

Li-Xian Sun, Fen Xu, Tatsuhiro Okada

National Institute of Materials and Chemical Research
1-1 Higashi, Tsukuba, Ibaraki 305, Japan

An amperometric glucose sensor based on the glucose oxidase immobilized on the pyrolytic graphite (PG) modified with tetraammineplatinum(U) chloride (TAPtC) and 5,10,15,20-tetrakis (4-methoxy-phenyl)-21H, 23H-porphine cobalt (U) (TMPPCo) as well as Nafion was studied. The performances among glucose sensors with or without TAPtC and/or TMPPCo were compared. The compositions of membranes of glucose sensors were optimized by chemometrics method. Sensor containing TAPtC, TMPPCo and Nafion with the optimal membrane composition showed satisfactory characteristics.

To Japanese Contents To English Contents
12.

耐熱酵素グルコキナーゼを用いたISFET型センサによる二糖類の測定

青木　一仁、石丸　雄大、飯田　武揚

埼玉大工

DISACCHARIDES SENSING BY ISFET-TYPE SENSOR USING THERMOPHILIC GULCOKINASE

Kazuhito AOKI, Yoshihiro ISHIMARU, and Takeaki IIDA

Department of Functional Materials Science , Faculty of Engineering, Saitama University
255 Shimo-okubo, Urawa-shi, Saitama-ken 338, Japan

An ion sensitive field effect transistor (ISFET) glucose sensor using an immobilized thermophilic glucokinase from a thermophilic bacterium Bacillus stearothermophilus, was applied to the lactose sensor. The ISFET sensor, on which thermophilic glucokinase, β-D-galactosidase and bovine serum albumin (BSA) was immobilized by glutaraldehyde, was able to determine the lactose concentration. Moreover, the ISFET maltose sensor, on which thermophilic glucokinase, α-D-glucosidase and BSA was immobilized by glutaraldehyde, was able to determine the sucrose and maltose concentration.

To Japanese Contents To English Contents
13.

微小尿素センサーの人工透析治療への検討

田中栄次、土本和憲、阪口利文*、村上裕二*、横山憲二*、民谷栄一*

澁谷工業（株）、北陸先端科技大*

EXAMINATION OF THE MICROSENSOR FOR UREA IN DIALYSIS TREATMENT

Eiji TANAKA, Kazunori TSUTIMOTO, Toshifumi SAKAGUCHI*, Yuji MURAKAMI*, Kenji YOKOYAMA*, and Eiichi TAMIYA*

Medical Equipment Dept., Mechatronics Production Div., Shibuya Kogyo Co., Ltd.
2-232 Wakamiya, Kanazawa, Ishikawa 920, Japan
*Department of Materials Science, Japan Advanced Institute of Science and Technology, Hokuriku
1-1 Asahidai, Tatsunokuchi, Ishikawa 923-12, Japan

We have made a micro urea sensor that combines an Ion Sensitive Field Effect Transistor (ISFET) and urease. The sensor system is applicable to an evaluation of the characteristics in the dialysate in dialysis treatment. The urea concentration in the waste dialysate from the dialysis equipment was measured in an artificial dialysis treatment environment. Based on these results, the concentration of urea in the patient's blood can be estimated without the requirement of the blood. The sensor continuously responds the patient's urea concentration in waste dialysate of a dialysis machine. Thus, the sensor is suitable for real-time monitoring of the condition of artificial dialysis.

To Japanese Contents To English Contents
14.

ポリピロール/ポリイオンコンプレックス複合膜電極を用いたpHスタット型尿素センサシステムの設計

駒場慎一，瀬山倫子，藤野裕介，逢坂哲彌

早大理工・早大材料技術研

UREA SENSING BY pH-STAT SYSTEM WITH POLYPYRROLE/POLYION COMPLEX COMPOSITE FILM ELECTRODE

Shinichi KOMABA, Michiko SEYAMA, Yusuke FUJINO, and Tetsuya OSAKA

Department of Applied Chemistry, School of Science and Engineering,Kagami Memorial Laboratory for Materials Science and Technology, Waseda University
Shinjuku-ku, Tokyo 169, Japan

Amperometric urea sensing system based on pH-stat was constructed with polypyrrole/polyion complex (PPy/PIC) composite film electrode, which demonstrated high sensitivity as potentiometric urea sensor. In this pH stat system, a generating electrode (G. E.), a nickel mesh anode, was positioned near the PPy/PIC electrode. In order to maintain constant pH aroud the PPy/PIC, electrolysis of water on the G. E. was controlled by potentiostat. And then, the near-linear relationship between the electrolysis current and urea concentration was obtained.

To Japanese Contents To English Contents
15.

SPV法を用いた新しいコリンエステラーゼ固定化バイオセンサ

フェドセエバ・オルガ、内田 秀和*、勝部 昭明*、石丸 雄大、飯田 武揚

埼玉大工

NOVEL TYPE BIOSENSOR BASED ON IMMOBILIZED CHOLINESTERASE USING SPV TECHNIQUE

O.V. FEDOSSEEVA, Hidekazu UCHIDA*, Teruaki KATSUBE*, Yoshihiro ISHIMARU and Takeaki IIDA

Department of Functional Materials Science and *Department of Information and Computer Sciences, Faculty of Engineering, Saitama University
255 Shimo-okubo, Urawa-shi, Saitama-ken 338, Japan

The silicone based device, Surface Photo Voltage (SPV) technique was applied to a novel cholinesterase biosensor. The SPV is a transducer that transduces the surface potential of the device, especially pH of the solution near the surface. Cholinesterase acetyl from bovine erythrocytes and cholinesterase butyryl from horse serum were immobilized on a silicon surface using polyvinyl alcohol and glutaraldehyde. The results suggested that the novel type biosensor, based on immobilized cholinesterase using SPV technique, will be used to develop various biosensors and immunosensors.

To Japanese Contents To English Contents
16.

SPR方式免疫センサの高感度化のための表面設計

外山滋、堂前成正*、宇佐美論*、掘越弘毅*、碇山義人

国立リハビリ研、東洋大工*

SURFACE DESIGN FOR THE ENHANCEMENT OF SENSITIVITY OF SPR BASED IMMUNOSENSOR

Shigeru TOYAMA, Narumasa DOUMAE*, Ron USAMI*, Kouki HORIKOSHI*, and Yoshihito IKARIYAMA

Research Institute, National Rehabilitation Center for the Disabled
4-1 Namiki, Tokorozawa 359, Japan
*Faculty of Engineering, Toyo University
2100 Nakanodai, Kujirai, Kawagoe 350, Japan

A novel SPR device, where wave guide is fabricated at the surface of prism, has been developed. The device demonstrated sharp absorption in the light reflectance curve due not only to the insertion of P-polarized incident light, but also to S-polarized light. It is theoretically predicted that the absorption maximum angle of P-wave (resonance angle) changes when the refracted index of the media in the very neighborhood of the device surface changes. On the other hand, the absorption maximum angle of S-wave changes little. Therefore, one can remove drift by subtracting the absorption angle corresponding to P-wave with that corresponding to S-wave, during the time-course measurement of immunoreaction-related SPR at the surface of device.

To Japanese Contents To English Contents
17.

発光微生物を用いた環境モニタリングシステム

北川 圭、根上邦春*、松井暢人*、阪口利文**、村上裕二**、横山憲二**、民谷栄一**

（株）石川製作所、（株）イシメックス*、北陸先端科技大**

ENVIRONMENTAL MONITORING SYSTEM USING LUMINESCENT BACTERIA

Kei KITAGAWA, Kuniharu NEGAMI*, Nobuhito MATSUI*, Toshifumi SAKAGUCHI**,Yuji MURAKAMI**, Kenji YOKOYAMA ** and Eiichi TAMIYA**

Ishikawa seisakusho
Kanazawa, Ishikawa 920, Japan
*Ishimex, Matto, Ishikawa 924, Japan
**School of Materials Science, Japan Advanced Institute of Science and Technology, Hokuriku
1-1 Asahidai, Tatsunokuchi, Ishikawa 923-12, Japan

A reagent-type environmental monitoring system employing luminescent bacteria, Photobacteriumphosphoreum or recombinant Escherichia coli with luminescence related genes of V.fischeri was developed. The increased or decreased intensity of luminescence resulting from the cellular assimilation of organic compounds and its inhibition by toxin in wastewater was detected by a photomultiplier or photodiode. Luminescence intensity of both recombinant E.coli and P.phosphoreum, depended on the concentration of organic compounds. Especially, recombinant E.coli responded to saccharoids obviously. On the other hand, the light-emitting response of P.phosphoreum was in a linear relationship to BOD concentration of standard solution. Thesystem was also applicable to the detection of toxic substances such as trichloroethane and cupper.

To Japanese Contents To English Contents
18.

マイクロマシン技術を用いて作製したセンサーによる生体物質の測定

丹羽　修、　堀内　勉、鳥光　慶一

（NTT基礎研究所）

MEASUREMENT OF BIOLOGICAL MOLECULES USING A MICRO-SENSOR FABRICATED WITH A MICRO-MACHINING TECHNIQUE

Osamu NIWA, Tsutomu HORIUCHI and Keiichi TORIMITSU

NTT Basic Research Laboratories 3-1 Morinosato, Wakamiya, Atsugi, Kanagawa 243-01, Japan

An online sensor fabricated with a micro-machining technique was used to measure an excitatory neurotransmitter, L-glutamic acid. Since the sensor was fabricated at room temperature, the enzyme can easily be modified on the film electrode before covering it with a glass plate to form a flow channel. The enzyme modified electrode exhibits a high sensitivity because it is located in a thin layer flow channel and achieves high conversion efficiency. As a result, a detection limit lower than 50 nM was obtained. The sensor shows a fast response. The current starts to increase about 10 sec after sample injection at a flow rate of 4 ul/min. The sensor is sufficiently light to mount on a manipulator to measure a biological sample under a microscope.

To Japanese Contents To English Contents
19.

NOの新しい電気化学測定法の開発

春山哲也、小畠英理、椎野繁明、柳田保子、相澤益男

東工大生命理工

Novel electrochemical sensing for NO

Tetsuya HARUYAMA, Eiry KOBATAKE, Shigeaki SHIINO, Yasuko YANAGIDA and Masuo Aizawa

Department of Bioengineering, Faculty of Bioscience and Bioengineering, Tokyo Institute of Technology

Two types of electrochemical sensing system have been developed for NO. One is based on the heme - NO interaction, which employs a heat-denatured CytC. The other is an electrochemical sensing system with a spin-trap reagent. In the case of heat-denatured CytC system, heat-denatured CytC was molecularly assembled on a Au electrode to produce a smooth electrochemical oxidation and reduced. The heat denatured CytC assembling electrode exhibited a higher activity in reducing NO than native one with a resulting enhanced anodic current, when the electrode potential was set at 0 mV vs. AgAgCl. Using the heat-denatured CytC system, NO was determined rapidly in the range from 0.5 to 4μM in aqueous solution.
The other system based on the electrochemistry of a spin-trap reagent was employed a carboxy-PTIO (C-PTIO) nitric oxide (NO) scavenger, which was performed a reversible electrochemical reaction on the electrode. An oxidation current of PTIO increased depending on dissolved NO concentration at the range from 15 to 200μM.

To Japanese Contents To English Contents
20.

酸化物薄膜電極を用いたオプティカルリン酸イオンセンサ

清水陽一、古田雄介

九工大工

OPTO-ELECTROCHEMICAL PHOSPHATE-ION SENSOR BASED ON METAL-OXIDE THIN-FILM ELECTRODE

Youichi SHIMIZU and Yusuke FURUTA

Department of Applied Chemistry, Faculty of Engineering, Kyushu Institute of Technology
1-1 Sensui-cho, Tobata, Kitakyushu 804, Japan

Novel high-sensitive phosphate-ion sensors based on electrochromism of oxide thin-film electrodes were developed. Among the oxide thin-films tested, it was found that the cobalt oxide (Co3O4) thin-film electrode showed a remarkable change of the transmittance at 550-800 nm, under applying anodic potential at 0.4V vs. SCE, which was depending on hydrogen phosphate ion (HPO42-) concentration. The change of transmittance at 620 nm, the sensor signal, was almost linear to the logarithm of the HPO42- concentration between 10-6 and 10-2M. The 90% response time, when the electrode potential was changed from +0.4 to 0 V (vs. SCE) at 10-2M, was about 50s at room temperature. The Co3O4-based optical sensor hardly responded to NO3- or Cl- at the sensing condition.

To Japanese Contents To English Contents
21.

スルホン酸アルカリ基を有するポリマーの感湿特性

米里法道、松口正信、酒井義郎

愛媛大工

A HUMIDITY SENSOR USING POLYELECTROLYTES WITH ALKALI SULFONATE GROUP

NorimichiYonesato, Masanobu Matsuguchi and Yoshiro Sakai

Department of Applied Chemistry, Faculty of Engineering, Ehime University
3 Bunkyo-cho, Matsuyama 790, Japan

A humidity sensor using poly(2-acrylamido-2-methylpropane sulfonic acid(AMPS)) was prepared. Some of the film were transformed into alkali salts. The impedance at the same water contents of the film below 60%RH was low in the order Cs＜＜Rb＜＜K＜＜H＜＜Na＜＜Li. This order, except for H type, is the same as the order of the equivalent ionic conductivity at the infinite dilution. The major conduction carrier seems to be hydrated alkali ions. The response time was the shortest for the acid type, followed by the Cs and Rb salts. In addition, AMPS was copolymerized with 2-hydroxyethyl methacrylate(HEMA) in order to have the long-term stability in a humid atmosphere.

To Japanese Contents To English Contents
22.

架橋したポリクロロメチルスチレンの感湿特性

古川晃之　松口正信　酒井義郎

愛媛大工

A HUMIDITY SENCOR USING CROSSLINKED POLY(CHLOROMETHYL STYRENE)

Teruyuki FURUKAWA, Masanobu MATSUGUCHI and Yoshiro SAKAI

Department of Applied Chemistry Faculty of Engineering, Ehime University
3 Bunkyo-cho, Matsuyama 790, Japan

Poly chloromethylstyrene was simultaneously cross-linked and quaternized by the reaction with N,N,N',N'-tetramethyl-1,6-diaminohexane on the surface of an almina substrate which has a pair of platinum electrodes on it. The impedance of this device decreased as the relative humidity increased. The device with a higher the degree of quaternization showed a higher sensitivity due to the increase in the number of hydrophilic ammonium group. The hysteresis also depended on the degree of quaternization. The diffusion constant of water in the film was estimated according to the standard Fickian model. As the degree of quaternization increased, the diffusion constant increased, resulting in a decrease in hysteresis.

To Japanese Contents To English Contents
23.

自己ドープポリアニリンの熱特性とそのPVA複合膜の電気伝導度の湿度依存性

椎木　弘、才野貴之、中山雅晴、小倉興太郎

山口大工

THERMAL PROPERTIES OF SELF-DOPED POLYANILINE AND THE HUMIDITY-DEPENDENCE OF ELECTRICAL CONDUCTIVITY OF THE COMPOSITE FILM WITH PVA

Hiroshi SHIIGI, Takayuki SAINO, Masaharu NAKAYAMA and Kotaro OGURA

Department of Applied Chemistry, Yamaguchi University
Tokiwadai, Ube 755, Japan

Self-doped polyaniline, poly anthranilic acid (PANA), was prepared by the chemical polymerization of antranilic acid with ammonium peroxydisulfate. Thermal characteristics of PANA were determined by the thermogravimetry / mass (TG/MS) analysis. The electrical conductivity of the 0.07 vol% PANA / 99.93% PVA composite film was linearly related with the atmospheric humidity, extending from 3.0×10-5 to 0.5 S・cm-1 upon the change in humidity from 8% to 98%. The measurements performed in both moistening and desiccating processes accompanied no any hysteresis. The humidity-dependency of conductivity of the composite was rationalized by the shift of the equilibrium between the conducting salt and the insulating base forms of PANA depending on the atmospheric humidity.

To Japanese Contents To English Contents
24.

固体電解質CO2センサの応答機構に及ぼす金属炭酸塩 /NASICON界面状態の検討

川手秀樹、島ノ江憲剛、三浦則雄、山添　f

九大総合理工

INTERFACIAL STRUCTURE OF CO2 SENSING DEVICES USING Li2CO3-BaCO3/NASICON JUNCTION

Hideki KAWATE, Kengo SHIMANOE, Norio MIURA, Noboru YAMAZOE

Department of Materials Science and Technology, Graduate School of Engineering Sciences, Kyushu University,
Kasuga-shi, Fukuoka 816, Japan

Potentiometric devices combining NASICON (Na+ conductor, Na3Zr2Si2PO12) with a series of Li2CO3-BaCO3 phases were investigated for CO2 sensing properties and hetero junction structure involved. It was revealed that an excessive addition of BaCO3 to the auxiliary phase was effective for improving the CO2 sensing capability at lower temperatures: Li2CO3-BaCO3 (1:3) allowed normal operation down to 300℃ while Li2CO3 did down to 350℃. The analyses of the fractured surfaces by means of an electron probe micro analysis and SEM indicated the formation of an interfacial layer between NASICON and carbonates, the thickness and structure of which depended on the carbonate compositions used. As revealed by X-ray diffraction analysis, BaZrO3 was easily formed between NASICON and Li2CO3-BaCO3, suggesting the relevance of BaZrO3 to the lower temperature sensing capability.

To Japanese Contents To English Contents
25.

Li-遷移金属複合酸化物を固体基準極として用いたCO2センサー

張　益燦、千葉和則* 田川博章、朝倉祝治、土器屋正之、水崎純一郎**

横浜国大環境研、曙ブレーキ中研*、東北大科研**

CO2 SENSOR USING Li-TRANSITION METAL COMPLEX OXIDE AS SOLID REFERENCE ELECTRODE

Yi Can ZHANG, Kazunori CHIBA*, Hiroaki TAGAWA, Shukuji ASAKURA, Masayuki DOKIYA, Junichiro MIZUSAKI**

Institute of Environmental Science and Technology, Yokohama National University
Yokohama 240, Japan
*Akebono Brake Research and Development Center, Ltd
Saitama 348, Japan
**Research Institute for Scientific Measurements, Tohoku University
Sendai 980-77, Japan

An electrochemical cell was constructed for sensing CO2 with Li2CO3-Li3PO4-LiAlO2 system as an electrolyte and sensing-electrode and LiCoO3-Co2O4 as the solid reference electrode. The EMF of this cell responded well to changes of CO2 concentration. It's long term stability is good, the EMF kept constant for a period of about one month at 350℃ in an atmosphere containing 1000ppm CO2. The reason was confirmed thermodynamically. The chemical potential diagram of Li-Co-C-O system was proposed. It's attributed to a constant activity of Li controlled by an equilibrium among LiCoO2, Co3O4 and Li2O at the interface between the electrolyte and the solid reference electrode.

To Japanese Contents To English Contents
26.

空調用固体電解質型炭酸ガスセンサの開発

兼安一成、大塚和之、瀬戸口泰宏、中原 毅、作田伸広、麻生 功

フィガロ技研株式会社

DEVELOPMENT OF A CARBON DIOXIDE SENSOR BASED ON SOLID ELECTROLYTE FOR AIR QUALITY CONTROL.

Kazunari KANEYASU，Kazuyuki OTSUKA，Yasuhiro SETOGUCHI，Takeshi NAKAHARA， Nobuhiro SAKUTA，Isao ASO

FIGARO ENGINEERING INC.
1-5-11 Senbanishi，Mino，Osaka 562, Japan

A carbon dioxide sensor was set up using Na3Zr2Si2PO12 (NASICON) as a solid electrolyte and Li2CO3 as a carbonate phase．The EMF(electromotive force) was linear to the logarithm of CO2 concentration and hardly depended on interfering gases by using a new zeolite filter．The ΔEMF(EMFair-EMFgas) was stable even after the test of unpowered exposure to a high humidity atmosphere．The CO2 monitor in which CO2 concentration is calculated by the ΔEMF using a new renovating system of the standard EMF was developed as a monitor for air quality control．The output of the monitor indicated a good agreement with that of a usual NDIR analyzer at the field-test in an office．

To Japanese Contents To English Contents
27.

酸化インジウム系電極を用いた混成電位型ジルコニアセンサのNOx検知特性

朝見忠昌、盧　革宇、島ノ江憲剛、三浦則雄、山添　f

九大総合理工

NO OR NO2 SENSING CHARACTERISTICS OF MIXED-POTENTIAL-TYPE SENSOR USING STABILIZED ZIRCONIA AND INDIUM-BASED OXIDE ELECTRODE

Tadamasa ASAMI, Geyu LU, Kengou SHIMANOE, Norio MIURA, Noboru YAMAZOE

Department of Material Science and Technology, Graduate School of Engineering Sciences, Kyushu University
Kasuga-shi, Fukuoka 816, Japan

An electrochemical device using stabilized zirconia was coupled with a series of In2O3-based electrodes modified with rare-earth metal oxides. Among the seven electrodes tested,Pr6O11-In2O3 was found to give the best NO or NO2 sensing performance with excellent selectivity and fairly quick response at 350℃. The EMF of the device was almost linear to the logarithm of NO or NO2 concentration with a negative(for NO) or positive(for NO2) slope. A sensing mechanism involving mixed potential was confirmed based on the measurments of polarization curves and catalytic activities of the In2O3-based oxide systems.

To Japanese Contents To English Contents
28.

NO+-Ga11O17固体電解質を用いたNOセンサ

山本貴生、田村真治、今中信人、足立吟也

阪大工

NO SENSOR BASED ON NO+-Ga11O17 SOLID ELECTROLYTE

Takao YAMAMOTO, Shinji TAMURA, Nobuhito IMANAKA and Gin-ya ADACHI

Department of Applied Chemistry, Faculty of Engineering, Osaka University
2-1 Yamadaoka, Suita, Osaka 565, Japan

A NO sensor was fabricated with the combination of NO+-Ga11O17 and nitrite as a solid electrolyte and a reference electrode, respectively. NO+-Ga11O17 was prepared by ion-exchanging K+ and Rb+ in (K+,Rb+)-Ga11O17 for NO+ by immersing into a NOCl・AlCl3 molten salt. The sensor output was consistent with the relationship derived from Nernst equation at 190℃ and its response was accurate and reversible with the NO variation. The sensor shows a selective NO sensing performance at 130℃.

To Japanese Contents To English Contents
29.

ジルコニア固体電解質を使用した排気NOxセンサの開発

日比野高士、大塚孝喜*、石田　昇*、大島崇文*

名工研、日本特殊陶業（株）*

NOxSENSOR IN EXHAUST GASES USING YSZ AS A SOLID ELECTROLYTE

Takashi HIBINO, Takaki OTSUKA*, Noboru ISHIDA* and Takafumi OSHIMA*

National Industrial Research Institute of Nagoya
Hirate-cho, Kita-ku, Nagoya 462, Japan
*NGK SPARK PLUG CO., LTD.,
2808 Iwasaki, Komaki-shi, Aichi 485, Japan

The detection of NO in the presence of excess oxygen has been carried out using a reaction of the NO with the hydrogen formed by the electrolysis of water vapor. The concentration of NO in the sample gas was determined by measuring the decrease in concentration of hydrogen with the oxygen sensor. Two types of NO dectetions were demonstrated in this paper. The voltage signal in the one type was sensitive to the NO with low concentrations, whole the current signal in the other type was proportional to the NO concentration from 0 to 2000 ppm.


To Japanese Contents To English Contents
特別講演2.

ニオイセンサの開発と応用

高橋祥夫

新コスモス電機

DEVELOPMENT AND APPLICATION OF ODOR SENSORS

Sachio TAKAHASHI

Research and Development Department, New Cosmos Electric Co., Ltd.
Yodogawa-ku, Osaka 532, Japan

Brief explanation is given on a series of odor sensors which are based on metal oxide semiconductor. They are classified into three types, that is, bead type, thin film type and thick film type. Their applications are put to practical use such as portable odor detectors, stationary odor detecting systems, electric appliances security monitor and TVOC (total volatile organic compounds) detectors.

To Japanese Contents To English Contents
30.

酸化物薄膜の感ガス特性（Ｉ）
高NOx応答薄膜の探索

田中伸一郎，江坂享男

鳥取大工

GSA SENSING CHARACTERISTICS OF THIN OXIDE FILMS (I)
SURVEY OF HIGH NOx SENSITIVE THIN FILM

Shinichiro TANAKA, Takao ESAKA

Department of Materials Science,　Faculty of Engineering, Tottori University
4-101 Minami, Koyamacho, Tottori 680, Japan

The thin oxide films with various compositions were prepared by the RF magnetron sputtering method and their sensitivities for NO2 were investigated. The 0.1mol% Nb2O5- and 5mol% TiO2-doped SnO2 thin films showed good sensitivity for NO2. Furthermore, 5mol% MgO- and 3mol% ZnO-doped In2O3 thin films were found to show the highest sensitivity for NO2.

To Japanese Contents To English Contents
31.

pおよびn型半導体酸化物を組み合わせた電気抵抗式センサのNOx検知特性

玉置　純、長岡忠仁、山本善史、松岡政夫

立命館大理工

NITROGEN OXIDES SENSING PROPERTIES OF CONDUCTIVITY-TYPE SENSORS USING p- AND n-TYPE OXIDE COMPOSITES

Jun TAMAKI, Tadahito NAGAOKA, Yoshifumi YAMAMOTO, and Masao MATSUOKA

Department of Chemistry, Faculty of Science and Engineering, Ritsumeikan University
Kusatsu-shi, Shiga 525-77, Japan

Semiconductor gas sensors using p- and n-type oxide composites have been investigated for the detection of a small amount of NO. Among 16 kinds of p-n combinations tested, the Co3O4-Fe2O3 composite sensor showed the good sensing properties to NO at 300 ℃. The composite sensor having Co3O4 content of 20 wt% exhibited the maximum sensitivity as high as 2.8 to 50 ppm NO, while that to 50 ppm NO2 was 1.5, indicating a sensitive and selective nature to NO. The composite sensor showed the almost linear correlation between legalism of NO sensitivity and that of NO concentration in the range of 5-100 ppm NO. These results suggest that the Co3O4-Fe2O3 composite sensor can be a candidate of a solid-state NO sensor for combustion monitoring.

To Japanese Contents To English Contents
32.

転写印刷法によるガスセンサの作製及びそのNO2感度

川原昭彦、勝木宏昭、江頭　誠*

佐賀県窯業技術センター・長崎大工*

FABRICATION AND NO2 SENSITIVITY OF GAS SENSORS BY SLIDE-OFF TRANSFER　PRINTING METHOD

Akihiko KAWAHARA, Hiroaki KATSUKI and Makoto EGASHIRA*

Fine Ceramic Division, Saga Ceramics Research Laboratory
Arita-machi, Nishimatsuura-gun, Saga 844, Japan
*Faculty of Engineering, Nagasaki University
1-14 Bunkyo-machi, Nagasaki 852, Japan

Sensitivity of semiconductor gas sensors of thick film type were prepared by a slide-off transfer printing method, which is one of the most popular printing techniques in traditional ceramics. Slide-off transfer sheets of metal oxide powders of SnO2, In2O3 and TiO2 were fabricated by a screen printing method. Conditions were investigated to print the paste of raw material powders mixed with a printing oil as an organic binder. The oxide films on screen-printed paper were then transferred on an alumina substrate, on which a couple of interdigitated electrodes had been printed, to fabricate thick film sensors. By firing the transferred oxide films at 800℃ in air, very uniform films could be obtained for 1-4 times slide-off transferring in every case. Anyway, the slide-off transfer printing method for preparing thick film sensors has potential advantages such as simple preparation, easy control of film thickness, and easy stacking of different oxide layers not only on a flat substrate but also on a curved surface. Sensing properties to NO2 gas of sensors with a double-layer structure, which were made by stacking two sheets of different slide-off transfers in pile were examined.

To Japanese Contents To English Contents
33.

ポリピロール−ポリエチレン複合膜の伝導度に及ぼすアンモニアガスの影響

三輪昌作、松口正信、酒井義郎

愛媛大工

EFFECT OF AMMONIA GAS ON THE ELECTRICAL CONDUCTIVITY OF POLYPYRROLE-POLYETHYLENE COMPOSITE FILMS

Masanari MIWA, Masanobu MATSUGUCHI,and Yoshiro SAKAI

Department of Applied Chemistry, Faculty of Engineering, Ehime University
3 Bunkyo-cho, Matsuyama-shi 790, Japan

A composite film of polypyrrole-polyethylene was prepared by chemical polymerization of pyrrole in the porous polyethylene film. The effect of ammonia gas on the electrical conductivity of the composite films was examined. The electrical conductivity decreased upon the introduction of ammonia gas. The performance of such sensors was evaluated by measuring the sensitivity and the 80％ recovery time. The sensitivity increased with the PPy contents in the composite film, while the 80% recovery time became longer with the PPy contents.

To Japanese Contents To English Contents
34.

電流検出型NH3ガスセンサの電解液組成とガス選択性

石地　徹、飯島鉄也、高橋勝緒*

理研計器・理化学研究所*

EFFECT OF SOLUTION COMPOSITION ON SELECTIVITY OF AMPEROMETRIC AMMONIA GAS SENSOR

Toru Ishiji, Tetsuya Iijima and Katsuo Takahashi

Riken Keiki Co., Ltd.
2-7-6 Azusawa Itabashi-ku, Tokyo 174, Japan

An amperometric sensor for detection of NH3 has been developed on a pH sensitive anodic reaction of Ruthenium Oxide as a working electrode. To improve a selectivity of the ammonia against carbon dioxide, the solution composition of the sensor has been investigated. The sensor using the aqueous KCl solution containing high concentration of ethylene glycol showed good responses for NH3 but no response for CO2. A good linearity and stability have been obtained, which are useful characteristics for practical usage.

To Japanese Contents To English Contents
35.

TPPH2誘導体-高分子分散膜によるHClガスの検出

北川貴啓、田中一成*、青野宏通、中川克彦**、定岡芳彦

愛媛大工、M荏原総合研究所*、新居浜高専**

HCl GAS SENSING PROPERTIES OF TPPH2 DERIVATIVES DISPERSED IN ETHYLCELLULOSE FILM

Takahiro KITAGAWA, Kazunari TANAKA*, Hiromichi AONO, Katsuhiko NAKAGAWA**, and Yoshihiko SADAOKA

Department of Materials Science and Engineering, Faculty of Engineering Ehime University
3 Bunkyo-cho, Matuyama, 790-77, Japan
*Center for Advanced Technology, Ebara Research Co.,Ltd.,
2-1 Honfujisawa 4-chome, Fujisawa 251, Japan
**Department of Industrial Chemistry, Niihama National College of Technology
7-1 Yagumo-cho, Niihama 792, Japan

Optical HCl sensing properties were investigated for TPPH2 derivatives, 5-mono-(p-hydorxyphe-nyl)-10,15,20-tri-(p-alkylphenyl)porphin [TP(R)3(OH)PH2, R=H, -C(CH3)3, -OC8H17], dispersed in ethylcellulose(EC) film. The change of reflectance of the TP(R)3(OH)PH2 film at λmax=670nm was larger than that for TP(R)4PH2 film. However, the response time was prolonged by replacing R with -OH. The slow response time was improved by elevation of operating temperature and addition of dioctylphthalate as a plasticizer.

To Japanese Contents To English Contents
36.

ガスセンサの妨害成分のフィルタリングによる除去

橘川 重郎，中川 英元，福田 健三，朝倉 祝治，高橋 祥夫*，重盛 徹志*

横浜国大工・新コスモス電機*

THE ELIMINATION OF ALCOHOL INTERFERENCE FOR A GAS SENSOR　BY FILTERING METHOD

Shigeo KITSUKAWA, Hidemoto NAKAGAWA, Kenzo FUKUDA, Shukuji ASAKURA, Sachio TAKAHASHI* and Tesshi SHIGEMORI*

Department of Materials Science and Chemical Engineering, Faculty of Engineering, Yokohama National University
Hodogaya-ku, Yokohama, 240, Japan
*New Cosmos Electric Co., Ltd,
Yodogawa-ku, Osaka, 532, Japan

Some of oxide semiconductor gas sensors have practical sensitivities for CO, but the interference problems, especially that of ethyl alcohol, impair the wide usage. In this study, the elimination of alcohol interference for a oxide semiconductor gas sensor by filtering method was investigated. The materials were attached to air-intake of the sensor through glass fiber. Using Zeolite or γ-alumina, some effect of elimination is observed and the ethanol interference is almost removed without sensitivity change to carbon monooxide gas. The effective concentration range of this method covers a range in practical use.

To Japanese Contents To English Contents
37.

光ファイバー型水素センサに関する基礎検討

関本慎二郎、岡崎慎司、中川英元、福田健三、朝倉祝治、重盛徹志*、高橋祥夫*

横浜国大工、新コスモス電機*

A FIBER-OPTIC EVANESCENT-WAVE HYDROGEN GAS SENSOR USING PALLADIUM SUPPORTED TUNGSTEN OXIDE

S.Sekimoto, S.Okazaki, H.Nakagawa, K.Fukuda, S.Asakura, T.Shigemori* and S.Takahashi*

Department of Materials Science and Chemical Engineering,　Yokohama National University
　 Hodogaya-ku, Yokohama 240, Japan
*New Cosmos Electric Co.ltd.
Yodogawa-ku, Osaka, 532, Japan

Development of a hydrogen sensor using fiber-optic evanescent-wave was tried and characterized. In the presence of hydrogen gas, The strong optical absorption in the red ranges of visual radiation was observed with the Pd/WO3 dispersed in silicone resin. The changes in absorbance were proportional to the concentration of hydrogen gas. It is suggested that this resin was suitable for hydrogen sensitive clad material. The obtained optical fiber whose the core coated with the above resin as the clad responded to hydrogen gas sensitively.

To Japanese Contents To English Contents
38.

感ガス時における半導体式ガスセンサの容量変化および抵抗値変化の同時測定

小林博樹、三好雅徳、高田　義

新コスモス電機

Simultaneous Measurements of Capacitance and Conductance Changes of Semiconductor Gas Sensor When Exposed to Reducing Gases

Hiroki KOBAYASHI, Masanori MIYOSHI and Tadashi TAKADA

New Cosmos Electric Co., Ltd.,
2-5-4 Mitsuya-naka, Yodogawa-ku, Osaka 532, Japan

Simultaneous measurements of capacitance and conductance changes of semiconductor gas sensor, when exposed to reducing gases, were carried out using a sintered SnO2. It was found that informations from the measurements enabled one to identify gas species. For example C2H5OH, even if any concentration, was identified with a particular curve FC2H5OH on a two-dimensional map, whicth was described in terms of two independent variables, namely, semiconductor capacitance C and conductance G. In case a measured point (Cm,Gm), where m denotes a measured quantity, is located on the curve FC2H5OH, the detected gas shoud be identified as C2H5OH.
To Japanese Contents To English Contents
39.

室内温熱環境のガスセンサ出力への影響

大薮　多可志、吉浦　真由美、南保　英孝、木村　春彦

富山国際大、金沢大・大学院、金沢大・工、金沢大・工

OUTPUT CHARACTERISTICS ON TIN OXIDE GAS SENSOR DEPENDING ON INDOOR THERMAL ENVIRONMENT

Takashi　OYABU1），Mayumi　YOSHIURA2），Hidetaka　NANBO3），and　 Haruhiko　KIMURA3）

1）Faculty　of　Humanities,　Toyama　University　of　International　 Studies
Oyama-Cho,　Toyama　930-12, Japan

　 　The principal factors of an indoor thermal environment are Temperature and humidy. The output of a tin oxide gas sensor Is influenced by room temperature and humidity in a testing room. Accordingly, it is difficult to detect an accurate gas-concentration in the room using the gas sensor. The relationship between the sensor output and thermal environment has been examined over a year in this investigation. A function which shows the relation is derived using a simple equation. The sensor output is measured at the hour of rising, namely, the start of daily human activity in an experimental house. An indoor comfortable index can also be deduced roughly by the function.

To Japanese Contents To English Contents
40.

SiC-MIS型センサにおける高温中でのCO , O2 , H2Oの相互作用

中込真二、P.Tobias, A.Baranzahi, A. L.Spetz and I.Lundstrom

石巻専修大理工、リンシェピン大

INTERACTION OF CO, O2 AND H2O ON SiC-MIS TYPE SENSOR IN HIGH TEMPERATURE CONDITION

Shinji NAKAGOMI*, Peter TOBIAS, Amir BARANZAHI, Anita Lloyd SPETZ and Ingemer LUNDSTROM

* School of Science and Engineering, Ishinomaki Senshu University, Ishinomaki 986-80 Japan
S-SENCE and Laboratory of Applied Physics, Linkoing University, S-581 83 Linkoing, Sweden

High temperature sensors, Schottky diode and capacitors, based on catalytic metal-oxide-silicon carbide devices are investigated. The sensitivity of the devices at 600C to mixtures of carbon monoxide and oxygen is studied. A large binary response of the sensors to carbon monoxide similar to the sensor response to hydrogen gas is observed. Close to the stoichiometric ratio of carbon monoxide and oxygen the signal changes from a high to a low value corresponding to an excess of carbon monoxide and an excess of oxygen, respectively. The signal to carbon monoxide decreases in the presence of water vapour. However, the presence of water did not change the inflection point of reaction of CO and O2.

To Japanese Contents To English Contents
41.

SnO2系素子のメチルメルカプタンガス検出特性に及ぼす担持金属の効果

甲斐伸二、高尾雄二*、清水康博、江頭　誠

長崎大・工、海洋*

EFFECT OF THE METAL-LOADING ON THE CH3SH SENSING PROPERTIES OF SnO2-BASED SENSORS.

Shinji KAI, Yuji TAKAO*, Yasuhiro SHIMIZU, Makoto EGASHIRA

Department of Materials Science and Engineering, Faculty of Engineering,
*Graduate School of Marine Science and Engineering,
Nagasaki University
1-14 Bunkyo-machi, Nagasaki 852, Japan

Methylmercaptan gas sensing properties of SnO2 loaded with and without a noble metal or metal oxide have been investigated in the temperature range of 200 - 600℃. Pure SnO2 exhibited a relatively high sensitivity. Among the specimens tested, only the SnO2 loaded with 0.5 wt% Pt exhibited higher sensitivity than that of the pure specimen. Based on the data of the oxidation and desorption behavior of methylmercaptan, it is suggested that relatively high sensitivity and slow response behavior observed especially at low temperatures arises partly from the adsorption process of a positively charged SO2+ chemisorbed species formed by the oxidation of methylmercaptan.

To Japanese Contents To English Contents
42.

教育器材としての自作酸素センサと測定システム

石地　徹、寺谷敞介*、川島徳道**、高橋三男***、唐津優勝****

理研計器、東学芸大*、桐蔭横浜大**、東京高専***、扶桑製作所****

HANDMADE OXYGEN SENSOR AND MEASURING SYSTEM FOR SCIENCE EDUCATION

T. Ishiji, S. Teratani, N. Kawashima, M. Takahashi and M. Karatsu

Riken Keiki Co., Ltd.
2-7-6 Azusawa, Itabashi-ku, Tokyo 174, Japan

Chemical sensor would be a useful device for arousing interest in science in young people. Oxygen is a very suitable target material because it is indispensable to our life and is invisible. Electrochemical oxygen sensor can easily be assembled using two kinds of metal plates, a conventional plastic film which is permeable to oxygen, and an electrolyte. A gold plate as the cathode, a lead plate as the anode, a polyethylene film as the oxygen permeable film, an d sodium bicarbonate as the electrolyte are used in this experiment. The oxygen consuming process in a container where a candle or a disposable pocket warmer is placed could be monitored by the handmade sensor. The sensor signal was stored through an AD converter into a personal computer system.

To Japanese Contents To English Contents

To On-line Chemical Sensors Index Page (Japanese)
To On-line Chemical Sensors Index Page (English)