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The purpose of this paper is to provide a review of recent developments in electromagnetic radiation (EMR) sensing.

Following a short introduction, this paper discusses a selection of recent research and development activities concerning the sensing of gamma radiation, X‐rays and ultraviolet (UV) radiation.

This shows that novel sensors are being developed for all of these classes of EMR. Improved gamma sensors are attracting strong interest in the USA, reflecting concerns regarding nuclear security. Novel X‐ray and UV sensors are often being developed in response to new and emerging uses of these types of radiation.

This paper provides a technical review of recent research into sensors for detecting gamma radiation, X‐rays and UV radiation.

The purpose of this paper is to study the effect of gamma-rays on murexide (Mx) dye and its possible use as radiation dosimeters in two different dosimetry systems. The first system depends on the Mx dye as a liquid dosimeter. The second dosimetry system depends also on the same dye but as in a gel form, which is more sensitive to gamma-rays.

The prepared Mx (solutions/gels) have a considerable two peaks at 324 and 521 nm that upon irradiation, the intensity of these peaks decreases with the increasing radiation dose.

The gamma-ray absorbed dose for these dosimeters was found to be up to 2 kGy for the solution samples and 40 Gy for the gels. Radiation chemical yield, dose response function, radiation sensitivity and before and after-irradiation stability under various conditions were discussed and studied.

It is expected that the radiolysis of the Mx dye can be used as radiation dosimeters in two different dosimetry systems; liquid and gel dosimeters. This can be applied in a wide range of gamma radiation practical industrial applications in water treatment, food irradiation dosimeters, radiotherapy and fresh food irradiation and seed production.

Both of the prepared Mx dyes, either as solutions or gel samples, can be facilely prepared from commercially, cheap, safe, available chemicals and suitable for useful applied Mx solutions and gels radiation dosimeters.

Considerable headway is being made in the acceptance of non‐destructive testing methods for refinery construction and maintenance. If properly used, these techniques constitute a valuable tool for determining the quality of workmanship (in acceptance tests of refinery equipment) and the survival outlook of installed equipment which may be exposed to mechanical wear, erosion or corrosion. They find further application in locating obstructions which may form in pipelines or other equipment.

In recent years considerable effort has been devoted to developing modern electronic and optical means for inspecting pipelines and tubing in engineering, petrochemical and power plant. Down‐time in such installations can be extremely costly, running as high as thousands of pounds for one day's outage. Considerable expenditure can, therefore, be warranted in the application of inspection techniques to ascertain the state of tubular components either on load, or at programmed maintenance periods. This article surveys some of the more recent equipment developed for this purpose.

This paper aims to describe the effects of radiation on certain classes of sensors and electronic devices and discusses the sensors used in high radiation environments.

Following an introduction, this paper firstly discusses the effects of radiation on semiconductors. It then considers the sensor technologies employed in high radiation applications and examines the impact of radiation on MEMS devices. Finally, it describes a radiation‐tolerant imaging sensor technology.

Ionising and non‐ionising radiation in terrestrial and space environments can exert a detrimental effect on semiconductor devices and has led to the development of a range of radiation hardening technologies. Most of the sensors used in nuclear power plants utilise long‐established and well‐characterised technologies which are inherently radiation‐tolerant but silicon MEMS devices are more prone to damage and a range of failure mechanisms have been identified. Most conventional image sensors are susceptible to radiation damage but a radiation‐hard technology termed the charge‐injection device has been developed which overcomes these problems.

This paper provides details of the sensor technologies used in high radiation applications.

This paper aims to assess the Jos Plateau Tin-mining region as an abandoned mine area being used for housing development with a view to make recommendations.

Utilising secondary data, which maps out ten different locations in the region, this paper highlights the level of radioactive substances (X-ray, beta and gamma rays) and the presence of heavy metals in the environment, abandoned mines, home for the people as well as housing development within a derelict region. Face-to-face interviews were conducted with heads of selected settlement within the Jos Plateau Tin-mining region.

Subsequent analysis shows that the radioactive substances exceed the international standards and therefore have a serious impact on the health of the local population who reside in the affected area. This is particularly significant as people use the contaminated soil as a basic material for their homes as well as farming and food production.

With overpopulation of neighbouring city and rising house prices, an increasing number of people have moved to the Tin-mining areas often without any knowledge about the perils of contaminated soil. At the same time, the planning authority has no presence in the affected area, as it falls outside its jurisdiction.

However, there is an urgent need to address this problem and prevent people from moving to this area, otherwise this would become a serious long-term human catastrophe.

Drawing from international experience, the paper argues that it is possible to develop housing in former Tin-mining areas but require careful remediation and engagement by the public and private sector.

The discussion in this paper makes a case for appropriate physical planning measure as people build their homes on the abandoned Tin-mining areas, with the presences of heavy metals and radioactive substances which are dangerous to human health where the governments have not made provision to address the problem. It is a bridge linking a previous paper on the environment and now consideration on housing/home which together form part of an ongoing PhD research “A potential application of spatial planning in Jos, Nigeria”.

THE old and time‐tried chemical methods of determination of the technological properties of materials have, during the last 15 or 20 years, been accompanied and perfected by physical methods, such as the X‐ray or Gamma‐ray methods (i.e. the so‐called macroscopic and microscopic methods of material testing). These new methods have been developed to such an extent that the modern manufacture of sensitive and complicated apparatuses, such as aeroplanes, seems practically impossible without these ingenious methods of “ physical analysis.” The microscopic methods of determination particularly have been developed to a high degree of perfection, due to an equally rapid development of microscopic apparatus and auxiliary materials which had become necessary when from being an exclusively scientific apparatus the microscope was transplanted into the industrial laboratories. Microscopic testing of materials in vertical and oblique illumination is an absolutely indispensable aid of all industrial laboratories of to‐day.

With the drastically changed pattern of the retail food trade in recent years in which the retailer's role has become little more than that of a provider of shelves for commodities, processed, prepared, packed and weighed by manufacturers, the defence afforded by the provisions of Section 113, Food and Drugs Act, 1955 has really come into its own. Nowadays it is undoubtedly the most commonly pleaded statutory defence. Because this pattern of trade would seem to offer scope for the use of the warranty defence (Sect. 115) in food prosecutions it is a little strange that this defence is not used more often.

REGULATIONS The Secretary of State—

Combination of a number of sensors with different response parameters into sensor arrays would enhance the overall performance of the radiation detection system. This paper presents a conceptual approach to the development of sensor arrays system with instantaneous dose and dose rate readout. A dynamic selection of multiple sensors with various sensitivity and accuracy range is implemented by applying pattern recognition (PR) analysis, which maximizes measurement accuracy. A number of relevant PR methods are discussed.

Thick films based on NiO, ZnO, In₂O₃, CeO₂, TiO₂, CuO and CdO are the key sensing elements in the proposed approach. Pure and carbon‐doped metal oxides were screen‐printed on Si wafers to form pn‐heterojunctions. All devices were exposed to a disc‐type 137 Cs source with an activity of 370 kBq. The values of radiation damage of pn‐junctions were estimated from changes in their current‐voltage characteristics.

Sensors showed an increase in the values of current with the increase in radiation dose up to certain levels, exceeding these levels results in unstable dosimetric characteristics.

The sensitivity of metal oxide films to γ‐radiation exposure depends on their composition and thickness. Mixing the oxides in different proportions and the addition of conducting particles, such as carbon, alters films susceptibility to radiation. In particular, sensors based on such films have dose response characteristics with certain level of sensitivity and working dose range, conditioned by particular sensing material properties and the device structure.