Nanocomposites are sophisticated materials that incorporate nanostructures into matrix materials, such as polymers, ceramics and metals. Generally, the marine ecosystem exhibits severe variability in ...terms of light, temperature, pressure, and nutrient status, forcing the marine organisms to develop variable, complex and unique chemical structures to boost their competitiveness and chances of survival. Polymers sourced from marine creatures, such as chitin, chitosan, alginate, sugars, proteins, and collagen play a crucial role in the bioengineering field, contributing significantly to the development of nanostructures like nanoparticles, nanocomposites, nanotubes, quantum dots, etc. These nanostructures offer a wide array of features involving mechanical strength, thermal stability, electrical conductivity, barrier and optical characteristics compared to traditional composites. Notably, marine nanocomposites have distinctive roles in a wide spectrum of applications, among them anti-cancer, anti-microbial, antioxidant, cytotoxic, food packing, tissue engineering and catalytic actions. Sol-gel, hot pressing, chemical vapor deposition, catalytic decomposition, dispersion, melt intercalation, in situ intercalative polymerization, high-energy ball milling and template synthesis are common processes utilized in engineering nanocomposites. According to our literature survey and the Web of Science, chitosan, followed by cellulose, chitin and MAPs emerge as the most significant marine polymers utilized in the construction of nanocomposites. Taken together, the current manuscript underscores the biogenesis of nanocomposites, employing marine polymers using eco-friendly processes. Furthermore, significant emphasis in this area is needed to fully explore their capabilities and potential benefits. To the best of our knowledge, this manuscript stands as the first comprehensive review that discusses the role of marine-derived polymers in engineering nanocomposites for various applications.
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•Marine organisms are considered pivotal resources of polymers.•Green synthesis of nanocomposite overcomes the toxicity of conventional approaches.•Integration of nanotechnology to enhance the material properties of the polymers•Fostering a circular economy involves implementing sustainable disposal methods.•Nanocomposites derived from marine sources span a wide spectrum of applications.
Wastewater is water that has already been contaminated by domestic, industrial and commercial activity that needs to be treated before it could be discharged into some other water bodies to avoid ...even more groundwater contamination supplies. It consists of various contaminants like heavy metals, organic pollutants, inorganic pollutants and Emerging contaminants. Research has been doing on all types of contaminates more than a decade, but this emerging contaminants is the contaminants which arises mostly from pharmaceuticals, personal care products, hormones and fertilizer industries. The majority of emerging contaminants did not have standardized guidelines, but may have adverse effects on human and marine organisms, even at smaller concentrations. Typically, extremely low doses of emerging contaminants are found in the marine environment and cause a potential risk to the aquatic animals living there. When contaminants emerge in the marine world, they are potentially toxic and pose many risks to the health of both man and livestock. The aim of this article is to review the Emerging contaminate sources, detection methods and treatment methods. The purpose of this study is to consider the adsorption as a beneficial treatment of emerging contaminants also advanced and cost effective emerging contaminates treatment methods.
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•Sources and causes of Emerging Contaminants has been discussed.•Treatment methods and the Detection of Emerging Contaminants has been explained.•Different types of emerging contaminants and advancement in its treatment were reviewed.•Latest advances and further improvements in Adsorption of emerging contaminants were addressed.
China is considered to account for nearly a third of all plastic waste discharging from land to the ocean. To overall assess microplastic pollution status in Chinese coastal and marginal seas, this ...study summarized the abundance and characteristics of microplastics in the seawater, sediments and marine organisms. The results showed that the abundance of microplastics in the seawater of four major seas of China was 0.13–545 items/m³, and microplastic abundance in the sediments from the estuaries was 20–7900 items/kg, which are at middle level or even lower than those detected in other countries. By contrast, severe microplastic pollution was recorded in the estuaries, suggesting that plastic waste and microplastic interception measures should be conducted on the rivers to prevent the input of microplastics. In addition, microplastics were widely detected in marine fishes, mollusks, zooplankton, mammals and birds, which highlights the potential impacts of microplastic pollution on the whole marine ecosystem. Compared to the dry season, higher microplastic abundance was found in the rainy season, revealing that plastic waste recycling should be strengthened before the onset of rainy season. We suggest that all countries respond actively to the ubiquitous microplastic pollution through practical policies and measures to prevent microplastics from further damaging the marine ecosystem.
•Microplastic abundance in seawaters of Chinese coastal seas was 0.13–545 items/m³.•Microplastic abundance in the sediments from the estuaries was 20–7900 items/kg.•High microplastic pollution was found in the estuaries, especially in rainy season.•Microplastic level in Chinese seas was moderate or lower compared to other countries.
Plastic production has increased exponentially since its use became widespread in the 1950s. This has led to increased concern as plastics have become prevalent in the oceanic environment, and ...evidence of their impacts on marine organisms and human health has been highlighted. Despite their prevalence, very few long-term (>40 years) records of the distribution and temporal trends of plastics in the world's oceans exist. Here we present a new time series, from 1957 to 2016 and covering over 6.5 million nautical miles, based on records of when plastics have become entangled on a towed marine sampler. This consistent time series provides some of the earliest records of plastic entanglement, and is the first to confirm a significant increase in open ocean plastics in recent decades.
Organisms often swim through density-stratified fluids. Here, we investigate the dynamics of active particles swimming in fluid density gradients and report theoretical evidence of taxis as a result ...of these gradients (densitaxis). Specifically, we calculate the effect of density stratification on the dynamics of a force- and torque-free spherical squirmer and show that density gradients induce reorientation that tends to align swimming either parallel or normal to the gradient depending on the swimming gait. In particular, swimmers that propel by generating thrust in the front (pullers) rotate to swim parallel to gradients and hence display (positive or negative) densitaxis, while swimmers that propel by generating thrust in the back (pushers) rotate to swim normal to the gradients. This work could be useful to understand the motion of marine organisms in ocean or be leveraged to sort or organize a suspension of active particles by modulating density gradients.
Preparing ocean governance for species on the move Pinsky, Malin L; Reygondeau, Gabriel; Caddell, Richard ...
Science (American Association for the Advancement of Science),
06/2018, Letnik:
360, Številka:
6394
Journal Article
Recenzirano
Odprti dostop
Policy must anticipate conflict over geographic shifts
The ocean is a critical source of nutrition for billions of people, with potential to yield further food, profits, and employment in the future ...(
1
). But fisheries face a serious new challenge as climate change drives the ocean to conditions not experienced historically. Local, national, regional, and international fisheries are substantially underprepared for geographic shifts in marine animals driven by climate change over the coming decades. Fish and other animals have already shifted into new territory at a rate averaging 70 km per decade (
2
), and these shifts are expected to continue or accelerate (
3
). We show here that many species will likely shift across national and other political boundaries in the coming decades, creating the potential for conflict over newly shared resources.
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