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1 – 10 of over 1000In the protection against corrosion of lock gates and other harbour structures, the life expectation of the protection given is of major importance because of the high cost of…
Abstract
In the protection against corrosion of lock gates and other harbour structures, the life expectation of the protection given is of major importance because of the high cost of drying off structures and repainting them. This paper discusses the factors involved and describes some case histories of marine protection.
Rajkumar Devapiriam, Karthik S. and Santhy K.
The purpose of this study is to fabricate and compare the mechanical and thermal properties of Sansevieria and Kaans fiber reinforced polyester matrices composites.
Abstract
Purpose
The purpose of this study is to fabricate and compare the mechanical and thermal properties of Sansevieria and Kaans fiber reinforced polyester matrices composites.
Design/methodology/approach
Treated Sansevieria and Kaans fiber was used as reinforcement for the fabrication of polymer matrix composites. Kaans fiber, which was available plenty in the delta region, but physical and mechanical properties of Kaans fiber were low when it compared with Sansevieria fiber. To make use of Kaans fiber for the fabrication of composite, the physical and mechanical properties have to be enhanced. So Egg shell powder was selected as a filler material to enhance the Kaans fiber reinforced composite. The selected fibers were properly weaved after alkali treatment. A three-layered (0°/45°/0°) Sansevieria fiber reinforced polymer (S-FRP) and Kaans fiber reinforced polymer (K-FRP) composite plates were fabricated using the compression molding method. As per American Society for Testing and Materials standards, the specimens were cut and mechanical, thermal and absorption properties of Sansevieria and Kaans fiber composites were investigated experimentally.
Findings
Tensile and flexural test reveals that K-FRP composite has good ductility and bending property than S-FRP composite plate. But from the other test results, S-FRP possesses high elongation capability than K-FRP. Thermo gravimetric analysis, moisture absorption and swelling test too done which clearly appeared S-FRP composite plate has prevalent execution than K-FRP composite plate.
Originality/value
This original research study enlists the mechanical, thermal properties and absorption properties of fabricated S-FRP and K-FRP composite plates.
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Maria Thereza Medeiros Fernandes, Wilma Fabiana Ferreira da Silva, Romayana Medeiros Oliveira Tavares, Breno Gustavo Porfírio Bezerra, Rodrigo Antônio Ponce de Leon Ferreira de Carvalho and Karla Suzanne Florentino da Silva Chaves Damasceno
The study aims to analyze the composition and mineral profile of oyster shell powder (OSP) and assess its potential as a sustainable source of calcium.
Abstract
Purpose
The study aims to analyze the composition and mineral profile of oyster shell powder (OSP) and assess its potential as a sustainable source of calcium.
Design/methodology/approach
A total of two batches of OSP with different particle sizes had been evaluated for centesimal and mineral composition and microbiological quality. OSP with smaller particles (0.85 mm) was used in the production of bread: standard bread (SB) (0%), fortified bread (FB1) (3%) and FB2 (4%). Centesimal and mineral composition and sensory acceptance had been performed. The internal preference map had been constructed using principal component analysis. The Just About Right data and the influence of sensory attributes on bread acceptance had been assessed by a penalty analysis test.
Findings
OSP-0.85 mm had calcium content (478.47 ± 2.37 mg.g-1) lower than OSP-1.00 mm (521.15 ± 0.99 mg.g-1) due to retention of particles. In both batches, heavy metals such as chromium, nickel and copper had not detected. FB1 and FB2 had the best nutritional content compared to SB, with higher calcium content (mg.g-1) 0.69 ± 0.07; 13.76 ± 0.72 and 19.47 ± 1.99 for SB, FB1 and FB2, respectively. The internal preference map showed better acceptance of FB1 compared to FB2. The penalty test showed that this acceptance was penalized (p < 0.05) due to the sandy texture.
Originality/value
The large number of shells generated in the processing of oysters is an environmental problem and generates waste of a natural source of calcium. It has been demonstrated that oyster shell powder can be used as a natural and sustainable source of calcium in bread, requiring further studies to assess the bioavailability of calcium.
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Alan Elliott Richardson and Thomas Fuller
The purpose of this paper is to examine the use of a waste marine sea shell product incorporated into a concrete mix as an aggregate replacement. Utilising shells reduces the…
Abstract
Purpose
The purpose of this paper is to examine the use of a waste marine sea shell product incorporated into a concrete mix as an aggregate replacement. Utilising shells reduces the storage of shell waste, also reducing the need for quarried aggregate and has potential benefits of adding a different material to a design mix concrete mix design for improved performance.
Design/methodology/approach
The test methods used to evaluate the concrete were, British Standard tests for compressive strength (BS EN 12390-3:2002) and porosity (BS EN 12390-8:2009). A paired comparison test was carried out examining two different partial replacement shell aggregate mixes against a plain concrete control sample.
Findings
The results showed a reduction in compressive strength when 50 per cent of sea shells were used as an aggregate replacement, for both sand and gravel, compared to the control sample. Crushed and graded sea shells used in concrete displayed a lower porosity/permeability than plain concrete.
Originality/value
Whilst there is existing work relating to the compressive strength of concrete using sea shells, the porosity of concrete using sea shells has not been widely addressed and the paper investigates this aspect of sustainable concrete research.
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Abstract
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The purpose of this paper is to use a hybrid account of oil spills in Nigeria to explore the recursive relationship between a multinational company, specific shareholders and the…
Abstract
Purpose
The purpose of this paper is to use a hybrid account of oil spills in Nigeria to explore the recursive relationship between a multinational company, specific shareholders and the public. A response to Mr and Mrs Shareholders’ concerns is considered an exercise in corporate discursive hegemony and enacts rhetorical accountability.
Design/methodology/approach
The authors adopt Debord’s (1967, 1988) concept of the spectacle with Boje’s (2001) antenarrative approach as a critical postmodern framing of Shell’s narrative of oil spills in both local and global contexts. An antenarrative approach considers how stories are woven to produce a unified and omnipotent narrative or image.
Findings
MNCs face considerable uncertainties arising from the operational conditions in developing countries and produce a range of accounts for spectators. As theatrical events, they contribute to the spectacle of power that rationalises controversy and suppresses resistance.
Research limitations/implications
To overcome the limitations of using a single document as empirical material the authors consider the response letter as an example of an institutional framing of oil spill phenomena in general.
Social implications
By understanding the construction of the spectacle the authors open avenues for resistance to corporate discursive hegemony in the form of carnivalesque.
Originality/value
The paper adds to the understanding of hybrid forms of resistance in an era of increasing MNC power and reach. It demonstrates how the actual production and distribution has persuasive power as a form of rhetorical accountability.
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The paper examines how corporate affairs departments can use content analysis techniques. It does so by showing how Precis, the system developed by the author's company, was used…
Abstract
The paper examines how corporate affairs departments can use content analysis techniques. It does so by showing how Precis, the system developed by the author's company, was used to monitor the impact of media coverage in three examples: the disposal of Brent Spar; the management of a corporate brand in an adverse regulatory environment; and a new car launch.
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Muhamad Hasif Hussin, Nor Hazurina Othman and Mohd. Haziman Wan Ibrahim
This paper aims to investigate the use of calcined mussel shell (CMS) ash–cement mix in concrete that is found to increase the concrete resistance against carbonation.
Abstract
Purpose
This paper aims to investigate the use of calcined mussel shell (CMS) ash–cement mix in concrete that is found to increase the concrete resistance against carbonation.
Design/methodology/approach
The deposited ash from the calcination of the mussel shells at 1000°C was used to replace the ordinary Portland cement at 5 and 7 per cent of the cement weight. The test results from the control concrete specimens were compared to the test results from the experimental concrete specimens to analyse the effects due to the said replacements. Carbonation was carried out naturally in the environment where the concentration of the carbon dioxide gas was at 0.03 per cent, the relative humidity of 65 per cent and the temperature of 27°C for a maximum period of 120 days. Measurement of carbonation depth was taken in accordance to the BS EN 13295: 2004. The carbonation resistance of the concrete was assessed based on the degree of compliance with the common design life requirement of 50 years. The filler effect from the CMS was verified using the capillary absorption test (ASTM C1585: 2013) and the electron microscope.
Findings
Experimental concrete specimens containing 5 and 7 per cent of the CMS ash demonstrated better carbonation resistance compared to the control concrete specimens with a minimum attainable design life of 56 years which can reach a maximum of 62 years. Capillary absorption test results indicated that the concrete pores have been effected by the said filler effect and visual observation from the electron microscope confirmed, solidifying the statement.
Originality/value
The CMS ash is proven to contribute to the concrete’s resistance against carbonation. Also, the CMS ash is synthesized from waste materials which have contributed to the application of the green material in the concrete technology.
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Mônica Cavalcanti Sá Abreu and Claire Barlow
This paper aims to compare the CSR strategy, stakeholder engagement and overseas approaches of six leading companies that have large potential environmental and social impacts…
Abstract
Purpose
This paper aims to compare the CSR strategy, stakeholder engagement and overseas approaches of six leading companies that have large potential environmental and social impacts, influential stakeholders and notable CSR actions.
Design/methodology/approach
This is an exploratory survey based on interviews with senior executives from British and Brazilian companies operating in the steel, petroleum and retail sectors, that makes comparisons between and within them.
Findings
The British companies interviewed are more rule-based, adopt an implicit CSR approach, react to stakeholders' demands based on moral motives, and focus on environmental issues. The Brazilian companies reviewed in this study adopt an explicit CSR approach, have relational motives to engage with stakeholders, and are more concerned with building a responsible image and narrowing social gaps.
Research limitations/implications
The survey is based on the perceptions of the senior executives interviewed, which may or may not correspond to actual practices. The sample size restricts generalisation of the results, and the specific firms interviewed may not represent the prevailing CSR business strategy in their respective countries.
Practical implications
British companies can learn from the Brazilian experience how to become more innovative in a broader approach to CSR. Brazil should reinforce its legal framework to provide a more systematic and rule-based approach to CSR, close to the UK experience.
Originality/value
The way CSR is conceived and implemented depends on the ethical, socioeconomic, legal and institutional environment of the country in which the firm operates.
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