Japan, sensor development

In the near future, UV photodiodes made from polycrystalline wide band-gap semiconductors may fill the gap in the market. Although they have a lower sensitivity (photocurrent per area) they promise to have a better merit-rating in terms of photocurrent per sensor costs. The other major drawback of polycrystalline photodiodes, the risetime of micro- to milliseconds, is not relevant for household applications. Fuji Xerox Laboratories in Japan are developing visible-blind UV photodiodes made from polycrystalline GaN [12], while twlux AG in Berlin, Germany is developing visible-blind UV photodiodes made from polycrystalline titanium dioxide [13]. A prototype is shown in Fig. 5.45. 

Shichiri et al(ll) (Osaka University in Japan) has developed the micro needle type glucose sensor, which consisted of a hydrogen peroxide electrode and a GOX enzyme immobilized layer. The sensor was clinically used, but it had to be renewed after a few days because of a gradual decline in its output. 

Matsuura S 1993 New developments and applications of gas sensors in Japan Sensors Actuators B 13-14 7-11... 

Domestic wastewater contains a large amount of detergents, especially anionic surfactants, such as linear alkylbenzene sulfonates (LAS). A sensitive biosensor containing Trichosporon cutaneum has been developed in Japan and used to monitor river water [128,129]. With this sensor a detection limit of 0.2 mg 1" LAS has been reached. 

The production of gas sensors. The production records of various types of gas sensors for past five years in Japan are listed in Table I except for the oxygen and humidity sensors. The sensors produced in the largest quantity are of the semiconductive type, followed by the catalytic combustion and thermistor types. These sensors have been mostly applied to domestic uses such as gas leakage alarms or gas control systems for LP gas and town gas which are extensively used for cooking and heating in Japanese houses. This is why these sensors are manufactured on a large scale. Other electrochemical sensors have been developed mainly to monitor other gases. 

FET type humidity sensor. Although sensors based on a field-effect transistor (FET) appear to hold promise as a small and low-cost intelligent sensor, relatively few people have been engaged in the research on FET type sensors in Japan. In this respect, it is remarkable that a FET type humidity sensor was developed recently by Hijikigawa of Sharp Corp (9). The sensor is also worth notice as a new type of humidity sensor, which utilizes changes in electric capacitance of humidity sensitive membrane interposed between double gate electrodes. 

Eiichi Kimura is retired from the Department of Medicinal Chemistry at Hiroshima University in Japan. His recent research interests have included the supramolecular chemistry of macrocyclic polyamines and their use in molecular recognition and as zinc-enzyme models. These interests have led to the development of fluorophore sensors for Zn(II) [8] use of macrocycles to effect selective recognition of anions [9], nucleobases in polynucleotides [10], thymidine mono- and diphosphate nucleotides (11), carbonic anhydrase and carboxypeptidase [12], and development of Zn(II)-macrocycle anti-HIV agents [13], In May 2004, he received a Purple Ribbon Award from the Emperor of Japan. 

Table III is a summary presentation of the CCD image sensor products of various companies in Japan, while Figure 8 shows the change in numbers of elements for photo-electric transducers. In the background of this change there was a great improvement in the clarity of pictures in home video systems (the photo-sensor for surface recognition of course was not developed exclusively for these measurements but was adapted from the general type).

Based on information about various oxides used for the SE in NO sensors given above, the new concept of potentiometric measurement of total NO regardless of the NO2 (NO) ratio in the exhaust gases at high temperatures has been developed recently [24, 34, 35]. In 1999, the ability to measure total NO in exhaust gases by a new zirconia-based laminated-type sensor was reported by Riken Corporation, Japan [34]. Since then, this sensor structure has been modified, and the new total-NOx detection system is shown conceptually in Figure 3.6 [35]. The main functions in this system are as follows ... 

A very successful sensor suitable for urea measurement in blood has been developed for Hitachi (Japan) by Tokinaga et al. (1984). Two NH sensitive electrodes containing nonactin in a PVC membrane were integrated in an FIA device in a differential circuit. One electrode was... 

Bisphenol A (BPA) is a compound which is currently not regulated, but as it exhibits weak estrogenic properties it is a suspected endocrine disrupter [33]. BPA is widely used as a plasticizer in plastics such as polycarbonate and epoxy resins and thus it is a concern for water quahty. Soh et al. developed an SPR immunosensor based on inhibition assay to detect BPA [34]. They used a SPR-20 sensor instrument (DKK, Japan) with the sensor chip modified with thiol monolayer on which BPA was immobilized through BPA succinimidyl ester. Using a monoclonal antibody, detection of BPA in buffer at concentrations as low as 10 ngmL was achieved. Detection time was approximately 30 min and the sensor was demonstrated to be regenerable using... 

For the use of combustion monitoring, a TiOj semiconductor NO sensor has recently been developed by Satake et al.[25] of Tokuyama Soda, Japan, and is... 

All of the sensors described above are chemical sensors utilizing the chemical interaction between COg and a sensing material. In point of conventional analytical equipments, a extremely miniaturized IR sensor for COg was recently developed by Shibata et.al[71,72] of Sanyo Electric, Japan. Miniaturization was achieved by using a new type of psn-oelectric IR detector composed of LiTaOg, a solid-state chopper and an optical filter in a same... 

In consumer s use, applications of gas sensors related to environmental pollutant gases are carried out mainly for security and amenity. Examples of the applications are, for instance, in the protection from a incomplete burning of combustion apparatus for home use and in the ventilation or condition of indoor atmosphere. A combustion monitoring sensor using SnOj was developed by Tanaka et al.[110] of Figaro Engineering, Japan. The gas water-heater... 

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