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21 – 30 of over 4000
Article
Publication date: 1 June 1967

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…

Abstract

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.

Details

British Food Journal, vol. 69 no. 6
Type: Research Article
ISSN: 0007-070X

Article
Publication date: 1 March 1992

Baha A. Marouf, I.K. Al‐Haddad, N.A. Tomma, J.A. Mahmood and N.F. Tawfiq

An environmental radioactivity monitoring programme has beenestablished around the Tuwaitha nuclear site, Baghdad, Iraq, to ensurethe safety of the public living around the site…

Abstract

An environmental radioactivity monitoring programme has been established around the Tuwaitha nuclear site, Baghdad, Iraq, to ensure the safety of the public living around the site and to prove that the nuclear facilities operate within the limits set by competent Iraqi Authorities and international environmental protection standards. Exposure rate measurements were carried out with portable monitors. Gamma spectrometric analysis of environmental samples (soil, vegetables, fruits, and water) was carried out to ensure that radionuclides expected to be released from the site are not concentrated in the environment. The results of the monitoring programme indicated that the average exposure rate was similar to that of the background radiation in Iraq. Furthermore, some environmental samples contained very low‐activity concentrations of Cs‐137.

Details

Environmental Management and Health, vol. 3 no. 3
Type: Research Article
ISSN: 0956-6163

Keywords

Article
Publication date: 27 February 2020

Khalid Rabaeh and Ahmed Basfar

The purpose of this paper is to propose a new dithizone solution dosimeter for high radiation applications such as polymers applications and food irradiation.

Abstract

Purpose

The purpose of this paper is to propose a new dithizone solution dosimeter for high radiation applications such as polymers applications and food irradiation.

Design/methodology/approach

Gamma-rays cell of Co-60 source with 8.4 kGy/h dose rate was used to irradiate the dithizone solutions at different irradiation temperatures. The optical measurements of unirradiated and irradiated dithizone dye solution dosimeters were performed using a UV/VIS spectrophotometer at absorption peaks of 421 and 515 nm.

Findings

The new dosimeter improved significantly with the increase of dithizone dye concentrations from 0.025 to 0.1 mM. The dosimeter shows a perfect pre- and post-irradiation stability after irradiation for five days. Because of irradiation temperature dependence, the dithizone solution dosimeter should be corrected under actual processing conditions.

Practical implications

Dosimetry is a key point in quality control of radiation processing to assure that uniform and correct radiation doses are delivered to a region of interest. Therefore, this study introduces a dithizone solution dosimeter for high-dose radiation applications such as food irradiation, polymers applications and agriculture.

Originality/value

Ionizing radiation interacted with the ethanol solvent, resulting in the formation of free radicals, then these free radicals interacted with the dithizone molecule and changed the dye color from yellow to orange.

Details

Pigment & Resin Technology, vol. 49 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 3 October 2019

Sameh Mohamed Gafar and Nehad Magdy Abdel-Kader

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Practical implications

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.

Originality/value

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.

Details

Pigment & Resin Technology, vol. 48 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 18 January 2016

Jun Ni, Jifei Dong, Jingchao Zhang, Fangrong Pang, Weixing Cao and Yan Zhu

– The purpose of this paper is to improve the accuracy and signal-to-noise ratio (SN) of a crop nitrogen sensor.

Abstract

Purpose

The purpose of this paper is to improve the accuracy and signal-to-noise ratio (SN) of a crop nitrogen sensor.

Design/methodology/approach

The accuracy and wide adaptability of two spectral calibration methods for a crop nitrogen sensor based on standard reflectivity gray plates and standard detector, respectively, were compared.

Findings

The calibration method based on standard detector could significantly improve the measurement accuracy and the SN of this crop nitrogen sensor. When compared with the method based on standard gray plates, the measurement accuracy and the SN of the crop nitrogen sensor calibrated based on the standard detector method improved by 50 and 10 per cent, respectively.

Originality/value

This research analysed the calibration problems faced by the crop nitrogen sensor (type CGMD302) based on standard gray plates, and proposed a sensor calibration method based on a standard detector. Finally, the results of the two calibration methods were compared in terms of measurement accuracy and the SN of the crop nitrogen sensor.

Details

Sensor Review, vol. 36 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 23 August 2021

Mohamad Bekhit, Essam Fahim and Asmaa Sobhy

The purpose of this paper is to fall light on the possibility of using the biopolymer chitosan in gamma dose monitoring.

140

Abstract

Purpose

The purpose of this paper is to fall light on the possibility of using the biopolymer chitosan in gamma dose monitoring.

Design/methodology/approach

The chitosan films were irradiated to gamma rays in the range starting from 10 to 120 kGy at a dose rate of 1.4 kGy/h using 60Co gamma source. The ultra violet and visible (UV/Vis) spectrophotometry were used to examine the optical properties of chitosan film. Also, Fourier transform infrared (FTIR) analysis was used to detect and trace any change in structural bands that may take place upon irradiation.

Findings

Increase in optical density of the chitosan film was recorded at 298 nm that correlated with increasing in the absorbed doses. Change in color of the film from pale yellow to denser yellow was detected upon increasing the absorbed doses. The close investigation for UV/Vis and FTIR analysis nominates the chitosan film to be used as a label-dosimeter in the range of 10–120 kGy depending on chitosan concentrations. The chitosan film has an excellent stability in different environmental conditions with ±3.7% uncertainty in measurements (2σ, approximately equal to a 95% confidence level).

Research limitations/implications

Chitosan film may be used as a medium and high-dose monitor with an acceptable overall uncertainty in routine radiation processing

Originality/value

The useful dose range from 10 to 80 kGy was detected for different concentrations of chitosan (0.5, 1, 1.5 Wt%) that correlated with increasing the absorbed dose, which is assigned to the linear parts in the target response curves. For the dose range 10–120 kGy, the film may be used as label dosimeter with detected color change from pale yellow to dense yellow.

Details

Pigment & Resin Technology, vol. 51 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 6 September 2019

Andreas Diermeier, Dirk Sindersberger, Peter Angele, Richard Kujat and Gareth John Monkman

Ultrasound is a well-established technology in medical science, though many of the conventional measurement systems (hydrophones and radiation force balances [RFBs]) often lack…

Abstract

Purpose

Ultrasound is a well-established technology in medical science, though many of the conventional measurement systems (hydrophones and radiation force balances [RFBs]) often lack accuracy and tend to be expensive. This is a significant problem where sensors must be considered to be “disposable” because they inevitably come into contact with biological fluids and expense increases dramatically in cases where a large number of sensors in array form are required. This is inevitably the case where ultrasound is to be used for the in vitro growth stimulation of a large plurality of biological samples in tissue engineering. Traditionally only a single excitation frequency is used (typically 1.5 MHz), but future research demands a larger choice of wavelengths for which a single broadband measurement transducer is desirable. Furthermore, because of implementation conditions there can also be large discrepancies between measurements. The purpose of this paper deals with a very cost-effective alternative to expensive RFBs and hydrophones.

Design/methodology/approach

Utilization of cost-effective piezoelectric elements as broadband sensors.

Findings

Very effective results with equivalent (if not better) accuracy than expensive alternatives.

Originality/value

This paper concentrates on how very cost-effective piezoelectric ultrasound transducers can be implemented as sensors for ultrasound power measurements with accuracy as good, if not better than those achievable using radiation force balances or hydrophones.

Article
Publication date: 26 August 2014

Ping Yang and Guangzhen Xing

This article aims to propose a new measurement method for ultrasonic power based on self-reciprocity theorem which turns the estimation of ultrasonic power to the measurement of…

Abstract

Purpose

This article aims to propose a new measurement method for ultrasonic power based on self-reciprocity theorem which turns the estimation of ultrasonic power to the measurement of first echo current and open-circuit voltage of the driving source.

Design/methodology/approach

The formula for ultrasonic power is derived which has corrected the position of pressure reflection coefficient on the interface of water and steel. The diffraction correction for focusing transducers is evaluated using numerical computation of the Rayleigh integral. One way to estimate the reflection coefficient of focusing beams on heterogeneous interface is also depicted.

Findings

Comparison experiment with radiation force balance method demonstrates that ultrasonic power measurement using self-reciprocity is sound in theory and feasible in practice.

Originality/value

It has a better capability of anti-environmental interference and, thus, can be extended to low-level and high-frequency power measurements.

Details

Sensor Review, vol. 34 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 7 September 2012

Robert Bogue

The purpose of this paper is to describe the techniques and technologies used in a selection of sensors which operate in extreme environments.

Abstract

Purpose

The purpose of this paper is to describe the techniques and technologies used in a selection of sensors which operate in extreme environments.

Design/methodology/approach

Following a short introduction, this paper discusses the technologies used in a range of sensors, principally accelerometers and pressure, temperature and displacement sensors, used in environments characterised by elevated temperatures, radiation and high shock and vibration levels.

Findings

The paper shows that a range of different strategies is employed to allow sensors to operate in extreme environments. These include specialised designs, novel sensing technologies and others which are inherently capable of withstanding extreme conditions and materials which can perform in, or which are resistant to, these environments. Several new technologies are under development which aim to extend sensor performance to new levels.

Originality/value

This paper provides details of the technologies used in a range of sensors aimed at applications in extreme environments.

Details

Sensor Review, vol. 32 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 1 March 2003

K. Arshak and O. Korostynska

Thin films of tellurium dioxide (TeO2) and indium oxide (In2O3) mixtures were investigated for γ‐radiation dosimetry purpose. Samples were fabricated using thermal vacuum…

Abstract

Thin films of tellurium dioxide (TeO2) and indium oxide (In2O3) mixtures were investigated for γ‐radiation dosimetry purpose. Samples were fabricated using thermal vacuum evaporation technique. The electrical properties of mixed oxides thin films [(TeO2)1−x(In2O3)x, where x=0 and 10 per cent by weight] and their changes under the influence of γ‐radiation were investigated. Samples with contacts having a planar structure showed increase in the values of current with the increase in radiation dose up to a certain dose level. Thin films in the form of pn‐junctions were fabricated with (TeO2)1−x(In2O3)x as p‐type material and sulphur as n‐type material. These pn‐junctions exhibited Zener diode behaviour. The current‐voltage characteristics for as‐deposited and γ‐irradiated samples were recorded. The level of response for all the fabricated devices was found to be highly dependent on the composition of the exposed material.

Details

Sensor Review, vol. 23 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

21 – 30 of over 4000