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Acid sludge produced from regeneration of used lubricating oil was chemically treated in order to convert it in to a saleable product. Investigates treatment with different inorganic formulations. Determines and discusses the optimum formulation composition. Characterizes the spectroscopic analysis, thermogravimetric and rheology behaviours, and hydrocarbon type analysis (asphaltene, oil and resin) of the extracted multicomponent resin (MCR‐1). Uses the MCR‐1 for the preparation of gilsonite varnish. The physico‐chemical properties of the latter were determined and compared with those of a standard gilsonite varnish. Concludes that treatment of acid sludge with different salt formulations provides a potentially lowest cost source of gilsonite varnish for news ink and also helps reduce an environmental problem created by re‐refining used oil.

New N‐halamine polymeric compounds were prepared by reacting cyanuric acid and polyacrylonitrile. Grafting of acrylonitrile monomer onto cotton linters was carried out and the product was reacted with cyanuric acid and finally was chlorinated. Cyanoethylation of polyvinyl alcohol was performed using acrylonitrile monomer to give polyvinylcyanoethyl ether, which, in turn, was reacted with cyanuric acid. The biological activity of the various chlorinated compounds obtained was examined against Gram (+) and Gram (−) bacteria using columns and dishes methods. A high disinfecting power of the chlorinated compounds obtained was observed. Thus, the bacteria was deactivated after the first cycle without contact with the product. All of the compounds prepared were insoluble in water and most of inorganic solvents. These compounds were also found to be very stable and did not decompose to give any toxic compounds. Thus, the chlorinated compounds prepared had no harmful effects on humans.

To prepare bioactive polymeric materials by grafting methods and characterisation of the biological activity of such materials.

New bioactive polysaccharides were prepared by grafting of acrylonitrile onto water soluble starch and the resulted material was reacted with bioactive heterocyclic rings, converting to N‐halamine biocidal polymers by chlorination and to polyquats by converting it to quaternary ammonium salts using hydrochloric acid. The biological activity of the materials prepared against gram positive and gram negative bacteria was studied by three methods.

Most of the bioactive materials prepared showed high disinfecting power against bacteria.

The bioactive materials were prepared by grafting of acrylonitrile onto starch and then reacting the resultant material with sulphadiazine. Many other heterocyclic rings that contain tertiary nitrogen atoms or amide group can also be used.

The new bioactive materials prepared can be used in disinfection of drinking water, swimming pools, etc.

The materials prepared and the use of such materials for disinfection were novel.

Coral aggregate seawater concrete (CASC) is a new type of lightweight aggregate concrete that is becoming widely used in reef engineering. To investigate the corrosion behavior of different kinds of rebar in CASC exposed to simulated seawater for 0-270 d, the electrochemical techniques, including linear polarization resistance (LPR) technique and the electrochemical impedance spectroscopy (EIS), were used in the present work.

The electrochemical techniques, including LPR technique and the EIS, were used in the present work.

Based on the time-varying law of linear polarization curves, self-corrosion potential (E_corr), polarization resistance (R_p), corrosion current density (I_corr), corrosion rate (i), and the characteristics of EIS diagrams for different types of rebar in CASC, it can be found that the anti-corrosion property of them can be ranked as epoxy resin coated steel > 2205 duplex stainless steel (2205S) > 316 L stainless steel (316 L) > organic coated steel > ordinary steel. Additionally, the linear regression equation between R_p and charge transfer resistance (R_ct) was established. Finally, the EIS corrosion standard of rebar was established from the LPR corrosion standard, which provides a direct standard for the EIS technique to determine the condition of rebar in CASC.

The linear regression equation between polarization resistance and charge transfer resistance was established. And the EIS corrosion standard of rebar was established from the LPR corrosion standard, which provides a direct standard for the EIS technique to determine the condition of rebar in CASC.

This paper aims to reduce the cost, limit the time and increase raw material source availability, coral aggregate seawater concrete (CASC) composed of coral, coral sand, seawater and cement can be widely used for the construction of ports, levees, airports and roads to achieve practical engineering values. However, the naturally porous coral structure and abundant Cl⁻ in the seawater and coral lead to extremely severe reinforcement corrosion for CASC. It is well known that Cl⁻ is the main cause of reinforcement corrosion in the marine environment. Therefore, it is necessary to research the reinforcement corrosion of CASC in the marine environment.

In this study, linear polarization resistance was adopted to test the linear polarization curves of reinforcement in CASC with different exposure times. E_corr, R_p, I_corr and V_corr were calculated according to the weak electrochemical polarization theory and Stern–Geary formula. The effects of concrete cover thickness, exposure time, reinforcement types and inhibitor on reinforcement corrosion in CASC were analysed. The reinforcement corrosion degradation rule was determined, which provided theoretical support for the durability improvement, security assessment, service life prediction and service quality control of CASC structures in marine islands and reef engineering.

The corrosion resistance was enhanced with increased concrete cover thickness, and the concrete cover thickness for organic new coated steel should be at least 5.5 cm to reduce the reinforcement corrosion risks in CASC structures. The corrosion resistance of different types of reinforcements followed the rule: 2205 duplex stainless steel > 316 stainless steel > organic new coated steel > zinc-chromium coated steel > common steel. In the early exposure stage, the anti-corrosion effectiveness of the calcium nitrate inhibitor (CN) was superior to that for the amino alcohol inhibitor (AA). With the extension of exposure time, the decreasing rate of anticorrosion effectiveness of CN was higher than that of AA.

Reinforcement corrosion of CASC in a marine environment was studied. Concrete cover thickness, exposure time, reinforcement type and inhibitor influenced the reinforcement corrosion were investigated. New technique of reinforcement anti-corrosion in marine engineering was proposed. Possible applications of CASC in marine engineering structures were suggested.

The purpose of this paper is to develop a real-time methodology to detect damages in coating and metallic structure in buried pipelines by using DC bias added to AC signal under field operation conditions, including cathodic protection.

Impedance measurements were performed on buried pipeline for different field conditions, to develop a methodology to detect and locate damages by impedance distribution along the metallic structure.

Field condition measurements were conducted as a pilot test on a buried steel pipeline segment with a diameter of 16 inches and length of 20 km. The frequency-based technology shows some differences but overall good behavior between impedance magnitudes vs localization of the interface changes at the soil-coating-steel interface at different frequencies using DC bias added to AC signal under field operation conditions, including cathodic protection.

The methodology is not applicable to highly resistive soil or high degradation coatings.

In this work, we depict a methodology that describes real time monitoring technology for buried metallic structures using AC signal. This monitoring is capable to detect and locate real time damage occurrences on the pipe surface (coating break). Field measurements include different conditions, such as temperature, soil resistivity and soil physical structure and chemical composition.

In consideration of the satisfied application in the field of the methodology, it is believed that it can be used for the monitoring of damages in pipes in areas with high consequences and hence pipe integrity can be increased.

This real-time methodology is based on the impedance distribution signal and the differential changes along the pipeline under operating conditions. The results showed good agreement with the proposed methodology, which is able to discriminate some situations inherent of field conditions by using different impedance measurements performed along ±10 km of buried steel pipeline and assuming the reference location as the cathodic protection set up.

The preparation and characterisation of new bioactive polymeric materials.

New bioactive polysaccharide were prepared by grafting of acrylonitrile onto water soluble starch and then reacting with bioactive heterocyclic rings. The biological activity, against bacteria, of the materials prepared was studied.

Some of the prepared bioactive materials show high disinfecting power against bacteria.

The bioactive materials were prepared by grafting acrylonitrile onto starch and then reacting the resulting material with cyanuric acid and 2‐aminothiazole. Many other heterocyclic rings that contain tertiary nitrogen atom or amide nitrogen can also be used.

The new bioactive materials prepared can be used for disinfecting purposes.

Some of the materials prepared were used successfully in killing bacteria, as such, can be used as disinfecting materials.

This article uses a survey of Certified Management Accountants (CMA) in the six Arab Gulf Cooperation Council (GCC) countries to examine the importance that CMAs place on a number of management accounting practices for the efficient operation of their business and to determine the degree of adoption of that management accounting practice by their organization. The findings indicate a large discrepancy between what accountants consider effective management accounting tools and the use of those tools by their companies’ senior management team. Evidence suggests that companies in the GCC rely on the traditional management accounting practices rather than the more recently developed tools. In addition, the management accountants of GCC companies feel that it would be more important for their businesses to emphasis a range of non‐financial tools as well as to adopt a more strategic management focus using tools.

This study aims to investigate the mediating role of management control system (MCS) characteristics in the relationship between state type, reflected through societal institutions (SIs), and two sets of management accounting techniques (MATs), namely, performance measurement techniques (PMTs) and cost measurement techniques (CMTs).

Structural equation modeling was used to analyze data from a cross-sectional survey of 136 firms in the United Arab Emirates (UAE).

The findings show a direct positive impact of state-type construct on MCS characteristics, and that MCS characteristics partially mediate the reported significant relationships between state type and the use of PMTs. While the findings show a similar positive relationship between state type and CMTs, MCS characteristics do not mediate this relationship.

Although these results are affected by limitations associated with the survey method used, they are useful in explaining the necessary conditions supporting the use of MATs in general and performance measurement techniques in particular.

The study uses a cross-section of companies in the UAE, an attractive global investment destination, as its sample. The results can help investors better understand the choice of MATs in the UAE and its relation to MCS characteristics.

This study contributes to management accounting literature by determining the mediating role of MCS characteristics on the relationship between state type and the choice of two sets of MATs, whereas existing literature assumes a direct relation between the two.

Insecticides are chemicals that are used to control damage or annoyance from insects. Generally, control is achieved by poisoning the insects by oral ingestion of stomach poisons, by contact poisons that penetrate through the cuticle, or by fumigants that penetrate through the respiratory system. Pojurowsky Leon has made wall paper washproof and contact‐insecticidal coating compositions by addition of 1–12% insecticide solutions in polar organic solvents in 15–45% amounts by usual vinyl‐acrylic or oil type emulsion lacquers. Coating dye compositions dispersible, in water and containing (MeO)2P(O)CH(OH)CC13 with lasting insecticide effect were prepared by Bozzay Jazsel, et al. In 1986, Lee, et al, have performed aqueous emulsions of insecticidal activity, containing hydrophilic silicone organic copolymer elastomer. Recently Moustafa, M., et al prepared and evaluated various coating compositions for their insecticidal activity. The binders used are chlorinated rubber, polyurethane and alkyd resins. Three kinds of insecticides with trade names sumicidin, sumithion and cyanox were studied. Cockroaches were the target insect. They showed that compositions based on alkyd or chlorinated rubber and containing 4% cyanox or sumithion as insecticide showed promising results as insecticidal and insect repellent coatings.