The role of biofilms in the corrosion of steel in marine environments

Transverse reinforcement plays a key role in the response behavior of reinforced concrete beams. Therefore, corrosion of steel stirrups may change the failure mode of elements from bending to shear, leading to a brittle and catastrophic crisis. It is important to strengthen reinforced concrete beams with corroded stirrups to enhance the shear resistance. This paper presents a formulation, based on the modified compression field theory, to estimate the ultimate shear of reinforced concrete beams strengthened with FRP, because of stirrup corrosion. The detrimental effect of corrosion on steel stirrup yield strength was taken into account by introducing an empirical decay law. The effective strain of FRP reinforcement was adequately evaluated by considering both debonding and tensile stress rupture. The proposed model was validated against collected experimental results, showing a good ability to evaluate shear strength. Moreover, a numerical analysis was carried out to highlight the role of the key parameters predicting the ultimate shear.

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Shark Attacks

10.1071/9781486307364 ◽

2017 ◽

Cited By ~ 1

Author(s):

Blake Chapman

Keyword(s):

Feeding Behaviour ◽

Scientific Information ◽

Movement Patterns ◽

Public Perceptions ◽

Controversial Issues ◽

Marine Environments ◽

The Media ◽

Shark Attacks ◽

Marine Biologist

Humans spend more time in or on the water than ever before. We love the beach. But for many people, getting in the water provokes a moment’s hesitation. Shark attacks are big news events and although the risk of shark attack on humans is incredibly low, the fact remains that human lives are lost to sharks every year. Shark Attacks explores the tension between risk to humans and the need to conserve sharks and protect the important ecological roles they play in our marine environments. Marine biologist Blake Chapman presents scientific information about shark biology, movement patterns and feeding behaviour. She discusses the role of fear in the way we think about sharks and the influence of the media on public perceptions. Moving first-hand accounts describe the deep and polarising psychological impacts of shark attacks from a range of perspectives. This book is an education in thinking through these emotive events and will help readers to navigate the controversial issues around mitigating shark attacks while conserving the sharks themselves.

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Biodiversity and Conservation

10.7591/cornell/9781501752773.003.0012 ◽

2021 ◽

pp. 338-353

Author(s):

Andrew V. Z. Brower ◽

Randall T. Schuh

Keyword(s):

Marine Environments ◽

Human Species ◽

Natural Habitats ◽

Types Of Knowledge ◽

Biological Systematics

This chapter assesses the role of biological systematics in conservation. Increasing awareness of the global destruction, diminishment, degradation, and fragmentation of natural habitats in terrestrial, aquatic, and marine environments has brought the study of “biodiversity” to a new level of intensity. Biodiversity, as the term is currently used, has many meanings, and its study ranges broadly across biology. There are, however, aspects of biodiversity that are strictly systematic, including (1) recognition and enumeration of the world's biota, and (2) inference of historical relations — both genealogical and geographical — among members of the biota. These types of knowledge can be used directly to inform our efforts for staving off continuing extinction at the hand of the human species.

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The Electrochemical Performance of δ-MnO2 Cathode Material for Aqueous Zinc-Ion Batteries: The Role of Current Collector

ECS Transactions ◽

10.1149/10501.0135ecst ◽

2021 ◽

Vol 105 (1) ◽

pp. 135-142

Author(s):

Mikhail A. Kamenskii ◽

Svetlana N. Eliseeva ◽

Veniamin V. Kondratiev

Keyword(s):

Electrochemical Performance ◽

Current Collector ◽

Zinc Ion ◽

Carbon Paper ◽

Galvanostatic Charge ◽

Capacity Fading ◽

Stainless Steel Mesh ◽

Current Collectors ◽

Corrosion Of Steel

Electrochemical properties of δ-MnO2-based cathode materials were studied in dependence on current collector used for electrode casting (stainless steel mesh, carbon paper and titanium foil) by galvanostatic charge/discharge measurements and cyclic voltammetry. It was shown that δ-MnO2-based electrodes cast on carbon paper demonstrate the most stable electrochemical performance in comparison with two other current collectors. This can be explained by corrosion of steel and passivation of titanium in mild aqueous electrolytes. Detailed study of carbon paper as current collector shows that pressing of electrodes leads to decreasing the porosity and fast capacity fading.

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