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Microbes that are able to grow on different surfaces can cause the deterioration of the underlying layers because of their metabolic activity. The purpose of this study is report the ability of fungi-bacteria consortium (FBC) in anaerobic media, and marine strain bacteria, to attach onto UNS 1008 carbon steel and zinc epoxy coats.

Impedance analysis, scanning electronic microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) were used to evaluate the adherence, biofilm formation and corrosion effect of FBC and marine bacteria onto UNS1008 carbon steel in anaerobic and aired conditions, respectively. In a similar way, the anticorrosive performance of hybrid coats on UNS 1008 carbon steel against marine bacteria.

In aerobic conditions, the outer layer shows a micro-crack appearance and several semi-sphere products that could be because of spore formation. In anaerobic conditions, evidence of iron sulfide surrounded by a mixture of sulfur-containing extracellular polymer substance was observed by SEM images and EDS analysis. The presence of hybrid coats (zinc epoxy with carbon nanotubes CNT content) affected the level of microbial adherence and the concentration of corrosion products (Fe₂O₃, Fe(OH)₂ and FeS); the cell attachment was lower when the steel surface was coated with Zn/CNTs.

This study opens a window for further evaluations of CNTs associated with metals as active materials to assess the corrosion on extreme corrosive environments, like in oil and gas industries the microorganisms play an important role either to increase or reduce the corrosion processes.

In case any of you are expecting a tale of mystery and intrigue on the high seas—complete with ships in hidden coves—I'm afraid I must disappoint you. My Drugs from the Sea story is not so dramatic, although it has its excitement (since the potential is always there for discovering a miracle drug from life in the sea).

The purpose of this paper is to prove and qualify the influence of textured surface substrates morphology and chemical composition on the growth and propagation of transplanted corals. Use additive manufacturing and silicone moulds for converting three-dimensional samples into limestone mortar with white Portland cement substrates for coral growth.

Tiles samples were designed and printed with different geometries and textures inspired by nature marine environment. Commercial coral frag tiles were analysed through scanning electron microscopy (SEM) to identify the main chemical elements. Raw materials and coral species were selected. New base substrates were manufactured and deployed into a closed-circuit aquarium to monitor the coral weekly evolution process and analyse the results obtained.

Experimental results provided positive statistical parameters for future implementation tests, concluding that the intensity of textured surface, interfered favourably in the coralline algae biofilm growth. The chemical composition and design of the substrates were determinant factors for successful coral propagation. Recesses and cavities mimic the natural rocks aspect and promoted the presence and interaction of other species that favour the richness of the ecosystem.

Additive manufacturing provided an innovative method of production for ecology restoration areas, allowing rapid prototyping of substrates with high complexity morphologies, a critical and fundamental attribute to guarantee coral growth and Crustose Coralline Algae. The result of this study showed the feasibility of this approach using three-dimensional printing technologies.

The purpose of this paper covers a perspective as related to sustainable development of natural resources with a focus on application of biotechnology in waste management.

The paper presents an overall view of industrial waste management practices as pertaining to substantiality of resources with emphasis on biodegradation of industrial pollutants. Methodologies employing biotechnology and striving towards the goal of sustainable development/production are discussed in this regard and particular attention is given to: regulatory consideration and trends; characterization of toxics for resource reuse; ecotoxicological assessment evaluations; treatment trends and innovative techniques, residual management.

Biotechnology is an important component needed to successfully achieve the goal of sustainability. “Value‐added” products from by‐products/waste and novel technologies employing biotechnical principles represent areas where significant opportunities exist.

The approach described here not only applies to water resource management but also includes multi‐media and multi‐disciplinary consideration.

The information presented herein hopefully will stimulate discussion and act as a catalyst for future direction. It perhaps may also serve as a point of reference for future evaluations of accomplishment.

The purpose of this investigation was to research the corrosion behavior of welded joints of bimetallic composite tube (X65/316L) welded with Inconel 625 in simulated sea water and in simulated production water, respectively.

The different electrochemical corrosion and galvanic corrosion behaviors of different welded zones were identified using the dynamic potential scan method and galvanic corrosion technique.

The heat-affected zone (HAZ) of welded joints was the most critical zone for corrosion. The closer to the welding line, more severe was the corrosion that was evident in the HAZ at room temperature. In welded joints of X65 tested in simulated seawater, tremendous corrosion occurred in the HAZ, followed by the base metal, and finally the welding line. However, there were few differences in corrosion of the different zones of welded joints in 316L in simulated production water. In such joints of 316L, corrosion comparatively attacked more easily to the HAZ. In galvanic corrosion tests, tremendous galvanic corrosion was evident on welded joints on X65, but comparatively slight gavanic corrosion appeared at welded joints in 316L. With the increased temperature, galvanic corrosion of welded joints was enhanced.

The results can provide reference for reducing the gavalic corrosion of welded bimetallic composite tube metal in the actual operation.

The purpose of this study was to investigate the impact of replacing two different fats on dyslipidemia, glycemic balance and adipose tissue redox status in obese rats.

Obesity was induced by feeding a high-mutton-fat diet during three months. An experimental group (n = 24) was divided into two groups that were fed during one month, 20 per cent of margarine or sardine oil. At Day 30, six rats from each group were sacrificed and the remaining rats were then subjected to a change in diet for one month: margarine was replaced by sardine oil and inversely, and then the rats were sacrificed. Three other groups (n = 6), each fed during two months, 20 per cent of margarine, sardine oil or mutton fat, served as controls.

Substitution of sardine oil by margarine compared to control sardine oil had increased triacylglycerols (TGs), glycosylated hemoglobin (HbA1c) and isoprostanes (IsoPs) values, but decreased thiobarbituric acid reactive substances (TBARS) and superoxide dismutase activity. Replacing margarine by sardine oil compared to control margarine reduced total cholesterol, TG, HbA1c, TBARS and IsoP contents but enhanced glutathione reductase and peroxidase activities. Nevertheless, comparing with the mutton fat, the two substitutions had improved glycemic and lipidic abnormalities and attenuated lipoperoxidation by enhancing enzymatic antioxidant defense. These favorable effects were better when margarine was replaced by sardine oil.

Substituting margarine with sardine oil seems to attenuate beneficial cardiometabolic risk markers associated to obesity and potentiate efficiency adipose tissue against the oxidative stress induced by the obesogenic diet.

India is a developing economy along with an increasing population estimated to be the largest populated country in about seven years. Simultaneously, its power consumption is projected to increase more than double by 2020. Currently, the dependence on coal is relatively high, making it the largest global greenhouse gas emitting sector which is a matter of great concern. The purpose of this paper is to evaluate the environmental impacts of the natural gas electricity generation in India and propose a model using a life cycle assessment (LCA) approach.

LCA is used as a tool to evaluate the environmental impact of the natural gas combined cycle (NGCC) power plant, as it adopts a holistic approach towards the whole process. The LCA methodology used in this study follows the ISO 14040 and 14044 standards (ISO 14040: 2009; ISO 14044: 2009). A questionnaire was designed for data collection and validated by expert review primary data for the annual environmental emission was collected by personally visiting the power plant. The study follows a cradle to gate assessment using the CML (2001) methodology.

The analysis reveals that the main impacts were during the process of combustion. The Global warming potential is approximately 0.50 kg CO₂ equivalents per kWh of electricity generation from this gas-based power plant. These results can be used by stakeholders, experts and members who are authorised to probe positive initiative for the reduction of environmental impacts from the power generation sector.

Considering the pace of growth of economic development of India, it is the need of the hour to emphasise on the patterns of sustainable energy generation which is an important subject to be addressed considering India’s ratification to the Paris Climate Change Agreement. This paper analyzes the environmental impacts of gas-based electricity generation.

Presenting this case study is an opportunity to get a glimpse of the challenges associated with gas-based electricity generation in India. It gives a direction and helps us to better understand the right spot which require efforts for the improvement of sustainable energy generation processes, by taking appropriate measures for emission reduction. This paper also proposes a model for gas-based electricity generation in India. It has been developed following an LCA approach. As far as we aware, this is the first study which proposes an LCA model for gas-based electricity generation in India. The model is developed in line with the LCA methodology and focusses on the impact categories specific for gas-based electricity generation.

The purpose of this paper is to study the correlation between different topographies and the reaction of Ulva Linza fouling species.

In this research, topographies with a different method, such as hot embossing and hot pulling, were achieved, and biological analyses were done with macroalgae Ulva Linza cells. The effect of topography via local binding geometry (honeycomb size gradients) and Wenzel roughness on the settling of Ulva microorganisms was tested.

As a result, Ulva spores confirmed different reactions to a similar set of tapered microstructures that was in agreement with the results on distinct honeycombs. The local binding geometry and the Wenzel roughness factor “r” were dominant on settling of Ulva Linza spores.

The reaction of an organism at the interface of vehicles’ substrate is powerfully affected by surface topographies.

The best embedment occurred on structures with bigger sizes than Ulva Linza’s spores. The density of settled spores was proportional to Wenzel roughness and the spores favour to attach to “kink sites” positions.

Unfortunately, unpleasant aggregation of marine biofouling on marine vehicles’ surfaces, generate terrific difficulties in the relevant industry.

There was a sharp relationship between Wenzel roughness and settle of Ulva Linza spores. The local binding geometry and the Wenzel roughness factor “r” were dominant on settling of Ulva Linza spores.

This paper aims to reveal the corrosion mechanism and corrosion development regulation of marine engineering structural steel in the marine environment and provide constructive suggestions for marine immersed tunnel engineering.

In this study, marine engineering structural steel’s behavior and corrosion prediction were carried out under the conditions of no cathodic protection and under-protection by artificially adding dissolved oxygen in a simulated seawater solution as a depolarizing agent.

Marine resources are rich in China. With the development of the economy and the improvement of engineering technology, marine engineering structural steel is used more and more widely. Engineering structural steel has a great risk of corrosion failure for long-term service in seawater, as seawater is a kind of corrosive medium containing various salts. At present, there are few projects and research studies available on the corrosion in the seawater environment of Q390C engineering structural steel, which is used in the Shenzhen–Zhongshan Link immersed tunnel steel shell at home and abroad. It cannot guide the corrosion of immersed tunnel steel shells in the ocean.

In this paper, the corrosion mechanism and corrosion development regulation of marine engineering structural steel in the marine environment are studied by accelerated corrosion test in the laboratory, which is of great significance to ensure the long-life durability of the immersed tunnel in marine engineering.

The relatively new and rapidly growing field of biotechnology encompasses several disciplines, including microbiology, biochemistry, and chemical engineering. The critical elements in biotechnology, which is not itself a discipline, are a biological organism or system, human intervention in the natural process, and the application of the results to an industrial process. One of the most dramatic and most basic examples of biotechnology is recombinant DNA technology, or genetic engineering, which involves the manipulation of genetic material. The production of genetically engineered organisms on a large scale for use in industrial processes combines the efforts of biologists and engineers. Microorganisms and other biological agents such as enzymes, whole cells, and cell components are used in industrial processes in the pharmaceutical, chemical, and food industries; and in energy production, agriculture, aquaculture, mining, waste disposal, and pollution control.