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The authors aim to investigate the use of pyrolysis for the processing of waste printed circuit boards (PCBs). The aim was to make the process of separating the organic, metallic, and glass fibre fractions of PCBs much easier and therefore make recycling of each PCB fraction more viable.

The PCBs were pyrolysed in a fixed bed reactor at 850°C. The organic fraction released by the boards was analysed by a variety of gas chromatography techniques. The residue that remained after pyrolysis was analysed by ICP‐MS to determine the type of metals that were present.

When PCBs were heated to 800°C in an oxygen free atmosphere, the organic fraction decomposed to form volatile oils and gases leaving behind the metal and glass fibre fraction of the boards. The pyrolysed boards were very friable and the different fractions (metal components, copper power boards, glass fibre, etc.) could be easily separated. The recovered metals could then be recycled by traditional routes with particular emphasis being placed on the recovery and recycling of rare and precious metals. The organic oils and gases which are produced during pyrolysis of PCBs can either be used as a chemical feedstock or as a fuel.

The research was only carried out on a very small scale so an investigation into scale‐up must be performed.

By using pyrolysis, the organic and metallic fraction of PCBs can be separated and recycled.

This paper presents a novel method for resource recovery from PCBs.

This study aims to investigate the compositional characteristics of aromatic hydrocarbons extracted from coals and to describe how the sulfur content influences the properties of coals and whether widely accepted maturity parameters are suitable for medium- to high-sulfur coal.

Four samples of medium- to high-sulfur coal were obtained from Fenxi, Shanxi Province, and studied using gas chromatography and gas chromatography–mass spectrometry (GC-MS).

The GC-MS results showed that there were five series of compounds were identified in the aromatic fractions: naphthalenes, phenanthrenes, oxygen-containing compounds, biphenyls and sulfur-containing compounds. The substituent group was mainly methyl. The content of dibenzothiophenes was high, which was attributed to their high thermodynamic stability. The presence of sulfur reduced the content of oxygen-containing compounds. A depositional environment that facilitated the formation of organic sulfur compounds led to a higher content of naphthalenes.

The development of methods for removing organic sulfur compounds would benefit from a study of their nature, which would be important for improving the use of coal.

The requirement to test paint arises at every stage in the development and manufacture of coatings though the exact nature of the test procedure varies widely. For example, in the development of a formulation it will be necessary to evaluate changes in the decorative and protective properties of the coating on its substrate, whilst once the product is in production quality control testing will be required. This typically involves rapid evaluation of liquid and dried paint samples to check for conformation to preset limits. A very wide range of techniques are used in these forms of testing though, in general, the equipment and procedures involved are familiar to all paint technologists and include apparatus such as viscometers, glossmeters, colorimeters, hardness testers and artificial weathering machines.

This paper aims to give an overview about the state of the art and novel technologies used in gas sensing. It also discusses the miniaturization potential of some of these technologies in a comparative way.

In this article, the authors state the most of the methods used in gas sensing discuss their advantages and disadvantages and at last the authors discuss the ability of their miniaturization comparing between them in terms of their sensing parameters like sensitivity, selectivity and cost.

In this article, the authors will try to cover most of the important methods used in gas sensing and their recent developments. The authors will also discuss their miniaturization potential trying to find the best candidate among the different types for the aim of miniaturization.

In this article, the authors will review most of the methods used in gas sensing and discuss their miniaturization potential delimiting the research to a certain type of technology or application.

The purpose of this paper is to determine the fatty acid composition of the edible snail Turbo coronatus from the Bahrain sea.

Total lipid content was extracted and methyl esters of fatty acids (FAMEs) were prepared and analyzed by gas chromatography.

Gas‐liquid chromatography shows that saturated fatty acids (SFA) are the major forms of fatty acids, followed by polyunsaturated fatty acids (PUFA) and monounsaturated fatty acids (MUFA). The most abundant PUFA are linolenic acid (18:3n‐3), eicosapentaenoic acid (EPA 20:5n‐3), linoleic acid (18:2n‐6), and arachidonic acid (ARA 20:4n‐6), the MUFA 16:1 (n‐7), and the SFA 16:0, 14:0, 18:0 and 20:0. The sum of EPA and DHA is 8.04 per cent. The n‐3/n‐6 fatty acids ratio approximately (2:1) is within the range of marine molluscs. The principle differences in the fatty acid composition of Turbo coronatus than most marine molluscs is their low DHA (0.23±0.01 per cent), low PUFA (40.92 per cent), and high SFA contents (49.25 per cent). The principle differences in the fatty acid composition of Turbo coronatus from most marine molluscs is their low DHA (0.23±0.01 per cent), low PUFA (40.92 per cent), and high SFA contents (49.25 per cent).

The Turbo coronatus samples were collected from Shaikh Ebrahim Island; however, further studies regarding the fatty acid composition of Turbo coronatus from other locations are required.

The results suggest that Turbo coronatus feeds on bacteria‐enriched detritic matter as well as phytoplankton and algae. The low concentration of PUFA in relation to SFA in Turbo coronatus can be attributed to warm water, high salinity, and food availability.

The paper provides valuable information about the fatty acid contents in Turbo coronatus, and its feeding habits, and nutritional values.

Artificial fruit ripening is hazardous to mankind. In the recent past, artificial fruit ripening is increasing gradually due to its commercial benefits. To discriminate the type of fruit ripening involved at the vendors’ side, there is a great demand for on-sight ethylene detection in a nondestructive manner. Therefore, this study aims to deal with a comparison of various laboratory and portable methods developed so far with high-performance metrics to identify the ethylene detection at fruit ripening site.

This paper focuses on various types of technologies proposed up to date in ethylene detection, fabrication methods and signal conditioning circuits for ethylene detection in parts per million and parts per billion levels. The authors have already developed an infrared (IR) sensor to detect ethylene and also developed a lab-based setup belonging to the electrochemical sensing methods to detect ethylene for the fruit ripening application.

The authors have developed an electrochemical sensor based on multi-walled carbon nanotubes whose performance is relatively higher than the sensors that were previously reported in terms of material, sensitivity and selectivity. For identifying the best sensing technology for optimization of ethylene detection for fruit ripening discrimination process, authors have developed an IR-based ethylene sensor and also semiconducting metal-oxide ethylene sensor which are all compared with literature-based comparable parameters. This review paper mainly focuses on the potential possibilities for developing portable ethylene sensing devices for investigation applications.

The authors have elaborately discussed the new chemical and physical methods of ethylene detection and quantification from their own developed methods and also the key findings of the methods proposed by fellow researchers working on this field. The authors would like to declare that the extensive analysis carried out in this technical survey could be used for developing a cost-effective and high-performance portable ethylene sensing device for fruit ripening and discrimination applications.

The purpose of this paper is to investigate in situ production of aroma‐active esters in dairy foods so as to improve flavour and to produce fruity flavour concentrate.

Lipase, ethanol or bacterial cultures are added to dairy media (milk, cream or cheese) and incubated for a period of time (from hours to months). Samples are then taken and analysed for aroma‐active esters using gas chromatography (GC) or gas chromatography‐mass spectrometry (GC‐MS).

Analyses of samples show that significant levels of ethyl esters of fatty acids are produced in milk, cream, enzyme‐modified cheese and natural cheese. All the dairy foods possess an intense pleasant fruity aroma.

This is a natural way to generate fruity flavours in dairy foods to enhance flavour and thus, consumer acceptance. The fruity flavour concentrate can also be used as a flavouring ingredient in dairy and non‐dairy food applications. Natural pure esters may also be extracted, separated and concentrated for wider flavour and fragrance applications. This approach may provide a cost‐effective solution to the increasing surplus of milk fat.

This paper aims to provide a deeper understanding of the painting techniques, materials used and deterioration phenomena in a thin panel painting. As well as, straightening buckling in a thin panel painting and reinforcement have been used by an auxiliary support system.

This requires using several scientific and analytical techniques to provide a deeper understanding of the painting techniques, materials used, deterioration phenomena and a greater awareness of how well treatment the panel painting is. Visual observation and multispectral imaging (Visible Ultraviolet-induced luminescence, as well as Ultraviolet reflected and Infrared [IR]), optical Microscopy (OM), handheld X-ray fluorescence spectroscopy (XRF), X-ray diffraction, Fourier transform IR spectroscopy (FTIR) and gas chromatography were used in this case study.

The analytical study of a thin panel with different methods allowed defining that the thin panel painting consists of plywood panel, ground layer (white lead and animal glue) and painted layer (lead red, cobaltic black, chrome yellow, Venetian red, iron black and white lead and poppy oil). Also, these determined that a convex buckling was the main form of deterioration. The structure treatment was executed by using a wet compress to straighten the thin panel painting and followed by fixing a new special design of the second auxiliary support system on the back of the thin panel painting.

The importance of analytical study to determine the painting techniques, materials used, deterioration phenomena and how well treatment the panel painting is. As well as, using a wet compress to straightening of warping or buckling wooden panel painting. Also, the Plexiglas second auxiliary support system could use to reinforcement the wooden panel and control the wooden panel movements.

The analyses of trends in prosecutions under the Food and Drugs Act, 1955 and the various regulations, which we have prepared every two years or so, covering a three‐month period, have been so much appreciated by readers, both in the administration and the industry itself, that we have prepared a more extended survey, covering the whole of 1966. The survey, as before, takes the form of a month‐by‐month analysis of reports of legal proceedings received by us from all parts of the country, and as formerly records the prosecutions under similar groupings; cases under Section 2, subdivided into those relating to compositional offences, the presence of foreign bodies and those relating to mouldy food: false description cases under Section 6 of the Merchandise Marks Acts; Section 8, the unfit food provision, also subdivided with special categories for foreign bodies and mouldy food; Section 32, milk cases; cases under the Food Hygiene Regulations, 1960, with smoking offences separated; the Milk and Dairies Regulations, consisting almost entirely of prosecutions under Reg. 27, Meat Regulations, Preservative Regulations, Colouring Matter in Food Regulations, etc.

As environmental pressures increase, and more legislation is drafted, the need for research into alternative coating technologies intensifies. In the area of powder coating technology the primary aim must be to expand the potential applications for powder beyond the traditional markets and offer the technology as a true environmentally friendly coating process.