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This paper describes a study into the development of an optimum fabrication process for the batch production of thick film titanium oxide‐PVC pH electrodes. Multi‐factorial experimental plans are used to explore the effect of fabrication parameters on the average sensitivity of sensors and their batch variability. Analysis of the results indicates that a number of the factors have a small effect on the sensitivity. Factors of particular importance are identified and TiO₂ in a PVC binder is examined in detail. The optimal values for these fabrication values are identified and examined. Mechanisms for the experimentally observed sub‐Nernstian responses and immersion‐time variations in sensor behaviour are discussed.

The purpose of this paper is to report thick film environmental and chemical sensor arrays designed for deployment in both subterranean and submerged aqueous applications.

Various choices of materials for reference electrodes employed in these different applications have been evaluated and the responses of the different sensor types are compared and discussed.

Results indicate that the choice of binder materials is critical to the production of sensors capable of medium term deployment (e.g. several days) as the binders not only affect the tradeoff between hydration time and drift but also have a significant bearing on device sensitivity and stability. Sensor calibration is shown to remain an issue with long‐term deployments (e.g. several weeks) but this can be ameliorated in the medium term with the use of novel device fabrication and packaging techniques.

The reported results indicate that is possible through careful choice of materials and fabrication methods to achieve near stable thick film reference electrodes that are suitable for use in solid state chemical sensors in a variety of different application areas.

Sheds light on why there is now such a proliferation of new chemical sensors. Describes various olfactory sensors and their differing uses. Concludes that in some areas, although not as efficient as traditional methods, sensors do have some merit.

The purpose of this paper is to develop textile materials with a pH‐sensitive function.

As a start point, the feasibility of incorporating pH‐indicators in conventional textiles using standard dyeing processes was investigated. Next, a pH‐indicator was incorporated into a nylon nanofibrous structure by adding the dye to the polymer solution before the start of the electro‐spinning process.

The authors' results proved that it is possible to develop a pH‐sensor using conventional textiles dyed by a standard dyeing process. Also, the incorporation of a pH‐indicator dye into a nanofibrous structure was possible. Moreover, reproducible samples could be obtained. Furthermore, the majority of the obtained textile structures showed a clear colour change with a change in acidity. This halochromic behaviour was, however, different from the behaviour of the dyes in solution due to dye‐fibre interactions.

The knowledge obtained in this study can lead to the development of a textile pH‐sensor. This sensor can be used in a broad field of applications since a colour change is a non‐disturbing but clear signal which can perform a first warning function.

DEPLOY is a successful technology demonstration project showing how state of the art technology can be implemented to achieve, continuous, real‐time monitoring of a river catchment.

The DEPLOY system is a wide area network of monitoring stations delivering data in near real‐time. The demonstration sites chosen are based in the River Lee, which flows through Ireland's second largest city, Cork. The sites include monitoring stations in five zones considered typical of significant river systems and demonstrate the versatility of the technology available. Data were collected from stations at pre‐programmed intervals and transmitted to the DEPLOY servers either by short range ISM band radio or directly via the GSM GPRS network. The data were then processed and made available in a controlled manner at www.deploy.ie Findings – The project demonstrates the capability of multi‐sensor systems to remotely monitor temporal and spatial variations in water quality, through the identification of short‐term events. A system like DEPLOY could be used as a decision support tool by regulatory bodies in managing our aquatic environment with the potential to cut overall monitoring costs and provide better coverage representing long‐term trends in fluctuations of pollutant concentrations.

The demonstration of a truly heterogeneous water quality monitoring networked system was one of the first of its kind in Ireland. Based on the collected data DEPLOY can provide recommendations for water quality monitoring systems from various perspectives, technical, operational and strategic.

Telemetry capsules have existed since the 1950s and were used to measure temperature, pH or pressure inside the gastrointestinal (GI) tract. It was hoped that these capsules would replace invasive techniques in the diagnosis of function disorders in the GI tract. However, problems such as signal loss and uncertainty of the pills position limited their use in a clinical setting. In this paper, a review of the capabilities of microelectromechanical systems (MEMS) for the fabrication of a wireless pressure sensor microsystem is presented.

The circuit requirements and methods of data transfer are examined. The available fabrication methods for MEMS sensors are also discussed and examples of wireless sensors are given. Finally, the drawbacks of using this technology are examined.

MEMS for use in wireless monitoring of pressure in the GI tract have been investigated. It has been shown that capacitive pressure sensors are particularly suitable for this purpose. Sensors fabricated for wireless continuous monitoring of pressure have been reviewed. Great progress, especially using surface micromachining, has been made in recent years. However, despite these advances, some challenges remain.

Provides a review of the capabilities of MEMS.

Optical fibre sensors are finding wide applications in biotechnology and medicine, as a European specialist explains.

This article aims to review the different devices that are available for the in situ monitoring of analytes found in the marine environment.

Following a short introduction to the topic, this paper discusses physical‐ and chemical‐based sensors, automatic analysers (flow injection, spectroscopic and spectrometric), electrochemical devices and biosensors.

A wide range of in situ monitoring systems (and associated deployment apparatus) for measuring concentrations of various analytes (e.g. nutrients, organic chemicals and metallic elements) have been developed in recent decades. Many of these systems are still at the laboratory or prototype stage and are yet to be fully developed into commercially available products. The harsh conditions often found in the marine environment can further limit the utility and application of these sensors. Further development work is needed; however, the need now is for field deployments, validation and inter‐calibration between sensors and other analytical measurement techniques.

This paper provides up‐to‐date information on in situ technologies that are available, either at the laboratory and prototype stages or commercially, and are suitable for deployment in the marine environment. Applications of these sensing systems are discussed together with their associated advantages and disadvantages over other existing water monitoring methods.

The purpose of this paper is to review the applications of commercially available fibre optic sensors (FOSs) and consider the reasons for their use.

Following a short introduction, the paper discusses the applications of FOSs for physical variables, gases and chemical compounds and identifies the reasons for their use.

It is shown that, following over three decades of research, FOSs are employed in many physical sensing uses where particular, application‐specific features confer significant user benefits. They are employed to a far lesser extent to monitor gases and chemical compounds, where the intrinsic features of the technology are of less benefit.

This paper provides an account of the applications of FOSs that have emerged since their development in the 1970s.