scholarly journals Preparation and Characterization of Novel Magnesium Composite/Walnut Shells-Derived Biochar for As and P Sorption from Aqueous Solutions

Agriculture ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 714
Author(s):  
Vladimír Frišták ◽  
Martin Pipíška ◽  
Vladimír Turčan ◽  
Stephen M. Bell ◽  
Haywood Dail Laughinghouse ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Anthropogenic Sources ◽  
Walnut Shell ◽  
Natural Ecosystems ◽  
Functional Changes ◽  
P Sorption ◽  
Sorption Efficiency ◽  
Walnut Shells ◽  
Potential Capacity ◽  
Sorption From Aqueous Solutions

Elevated or unnatural levels of arsenic (As) and phosphorus (P) concentrations in soils and waterbodies from anthropogenic sources can present significant hazards for both natural ecosystems and human food production. Effective, environmentally friendly, and inexpensive materials, such as biochar, are needed to reduce mobility and bioavailability of As and P. While biochar features several physicochemical properties that make it an ideal contaminant sorbent, certain modifications such as mineral-impregnation can improve sorption efficiencies for targeted compounds. Here, we conducted sorption experiments to investigate and quantify the potential utility of magnesium (Mg) for improving biochar sorption efficiency of P and As. We synthesized a Mg-modified walnut shells-derived biochar and characterized its ability to remove As and P from aqueous solutions, thereby mitigating losses of valuable P when needed while, at the same time, immobilizing hazardous As in ecosystems. SEM-EDX, FTIR and elemental analysis showed morphological and functional changes of biochar and the formation of new Mg-based composites (MgO, MgOHCl) responsible for improved sorption potential capacity by 10 times for As and 20 times for P. Sorption efficiency was attributed to improved AEC, higher SSA, chemical forms of sorbates and new sorption site formations. Synthetized Mg-composite/walnut shell-derived biochar also removed >90% of P from real samples of wastewater, indicating its potential suitability for contaminated waterbody remediation.

scholarly journals Transfer of Cobalt Nanoparticles in a Simplified Food Web: From Algae to Zooplankton to Fish

Applied Nano ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 184-205
Author(s):  
Nanxuan Mei ◽  
Jonas Hedberg ◽  
Mikael T. Ekvall ◽  
Egle Kelpsiene ◽  
Lars-Anders Hansson ◽  
...  
Keyword(s):  
Food Web ◽  
Crucian Carp ◽  
Environmental Fate ◽  
Anthropogenic Sources ◽  
Natural Ecosystems ◽  
Fish Feeding ◽  
Aquatic Food ◽  
Significant Uptake ◽  
Co Nanoparticles ◽  
Crucian Carp Carassius Carassius

Cobalt (Co) nanoparticles (NPs) may be diffusely dispersed into natural ecosystems from various anthropogenic sources such as traffic settings and eventually end up in aquatic systems. As environmentally dispersed Co NPs may be transferred through an aquatic food web, this study investigated this transfer from algae (Scendesmus sp.) to zooplankton (Daphnia magna) to fish (Crucian carp, Carassius carassius). Effects of interactions between naturally excreted biomolecules from D. magna and Co NPs were investigated from an environmental fate perspective. ATR-FTIR measurements showed the adsorption of both algae constituents and excreted biomolecules onto the Co NPs. Less than 5% of the Co NPs formed heteroagglomerates with algae, partly an effect of both agglomeration and settling of the Co NPs. The presence of excreted biomolecules in the solution did not affect the extent of heteroagglomeration. Despite the low extent of heteroagglomeration between Co NPs and algae, the Co NPs were transferred to the next trophic level (D. magna). The Co uptake in D. magna was 300 times larger than the control samples (without Co NP), which were not influenced by the addition of excreted biomolecules to the solution. Significant uptake of Co was observed in the intestine of the fish feeding on D. magna containing Co NPs. No bioaccumulation of Co was observed in the fish. Moreover, 10–20% of the transferred Co NP mass was dissolved after 24 h in the simulated gut solution of the zooplankton (pH 7), and 50–60% was dissolved in the simulated gut solution of the fish (pH 4). The results elucidate that Co NPs gain different properties upon trophic transfer in the food web. Risk assessments should hence be conducted on transformed and weathered NPs rather than on pristine particles.

scholarly journals Hormetic Effects of Early Juvenile Radiation Exposure on Adult Reproduction and Offspring Performance in the Cricket (Acheta domesticus)

Dose-Response ◽  
2018 ◽  
Vol 16 (3) ◽  
pp. 155932581879749 ◽  
Author(s):  
Alexander M. Shephard ◽  
Vadim Aksenov ◽  
Jonathan Tran ◽  
Connor J. Nelson ◽  
Douglas R. Boreham ◽  
...  
Keyword(s):  
Low Dose ◽  
Acheta Domesticus ◽  
Anthropogenic Sources ◽  
Offspring Size ◽  
Radiation Stress ◽  
Natural Ecosystems ◽  
Offspring Performance ◽  
Early Juvenile ◽  
Wide Range ◽  
Survival And Reproduction

Exposure to low-dose ionizing radiation can have positive impacts on biological performance—a concept known as hormesis. Although radiation hormesis is well-documented, the predominant focus has been medical. In comparison, little research has examined potential effects of early life radiation stress on organismal investment in life history traits that closely influence evolutionary fitness (eg, patterns of growth, survival, and reproduction). Evaluating the fitness consequences of radiation stress is important, given that low-level radiation pollution from anthropogenic sources is considered a major threat to natural ecosystems. Using the cricket ( Acheta domesticus), we tested a wide range of doses to assess whether a single juvenile exposure to radiation could induce hormetic benefits on lifetime fitness measures. Consistent with hormesis, we found that low-dose juvenile radiation positively impacted female fecundity, offspring size, and offspring performance. Remarkably, even a single low dose of radiation in early juvenile development can elicit a range of positive fitness effects emerging over the life span and even into the next generation.

scholarly journals Polyanilines as New Sorbents for Hydrocarbons Removal from Aqueous Solutions

Materials ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2161
Author(s):  
Cristina Della Pina ◽  
Maria Antonietta De Gregorio ◽  
Pierluisa Dellavedova ◽  
Ermelinda Falletta
Keyword(s):  
Aqueous Solutions ◽  
Environmental Protection ◽  
Surface Properties ◽  
Health Risks ◽  
Water Remediation ◽  
Wastewater Remediation ◽  
Sorption Efficiency ◽  
Potential Applications ◽  
High Sorption ◽  
Green Procedure

Water remediation from hydrocarbons is crucial to reduce health risks. Numerous costly and, sometimes, sophisticated methods were proposed over the years. Herein, an innovative green procedure for porous polyanilines preparation is reported. Polyaniline (PANI) was synthesized by three different approaches ranging from traditional to more eco-friendly ones. Thermal, optical and morphological features of the resulting materials were investigated along with their surface properties. Finally, PANIs were tested as sorbents for hydrocarbons removal from waterbodies. Although an overall fast and high sorption efficiency is always observed, the effective hydrocarbons abatement performed by ‘green’ PANIs is particularly welcome in the context of environmental protection. Moreover, the sorption efficiency retention after five-run recycling tests suggests potential applications in wastewater remediation.

scholarly journals Merging Metagenomics and Spatial Epidemiology To Understand the Distribution of Antimicrobial Resistance Genes from Enterobacteriaceae in Wild Owls

2020 ◽  
Vol 86 (20) ◽  
Author(s):  
Elizabeth A. Miller ◽  
Julia B. Ponder ◽  
Michelle Willette ◽  
Timothy J. Johnson ◽  
Kimberly L. VanderWaal
Keyword(s):  
Antimicrobial Resistance ◽  
Resistance Genes ◽  
Spatial Epidemiology ◽  
Anthropogenic Sources ◽  
Resistant Bacteria ◽  
Metagenomic Sequencing ◽  
Wild Animals ◽  
Natural Ecosystems ◽  
Content Type ◽  
Antimicrobial Resistance Genes

ABSTRACT Antimicrobial resistance (AMR) is a well-documented phenomenon in bacteria from many natural ecosystems, including wild animals. However, the specific determinants and spatial distribution of resistant bacteria and antimicrobial resistance genes (ARGs) in the environment remain incompletely understood. In particular, information regarding the importance of anthropogenic sources of AMR relative to that of other biological and ecological influences is lacking. We conducted a cross-sectional study of AMR in great horned owls (Bubo virginianus) and barred owls (Strix varia) admitted to a rehabilitation center in the midwestern United States. A combination of selective culture enrichment and shotgun metagenomic sequencing was used to identify ARGs from Enterobacteriaceae. Overall, the prevalence of AMR was comparable to that in past studies of resistant Enterobacteriaceae in raptors, with acquired ARGs being identified in 23% of samples. Multimodel regression analyses identified seasonality and owl age to be important predictors of the likelihood of the presence of ARGs, with birds sampled during warmer months being more likely to harbor ARGs than those sampled during cooler months and with birds in their hatch year being more likely to harbor β-lactam ARGs than adults. Beyond host-specific determinants, ARG-positive owls were also more likely to be recovered from areas of high agricultural land cover. Spatial clustering analyses identified a significant high-risk cluster of tetracycline resistance gene-positive owls in the southern sampling range, but this could not be explained by any predictor variables. Taken together, these results highlight the complex distribution of AMR in natural environments and suggest that both biological and anthropogenic factors play important roles in determining the emergence and persistence of AMR in wildlife. IMPORTANCE Antimicrobial resistance (AMR) is a multifaceted problem that poses a worldwide threat to human and animal health. Recent reports suggest that wildlife may play an important role in the emergence, dissemination, and persistence of AMR. As such, there have been calls for better integration of wildlife into current research on AMR, including the use of wild animals as biosentinels of AMR contamination in the environment. A One Health approach can be used to gain a better understanding of all AMR sources and pathways, particularly those at the human-animal-environment interface. Our study focuses on this interface in order to assess the effect of human-impacted landscapes on AMR in a wild animal. This work highlights the value of wildlife rehabilitation centers for environmental AMR surveillance and demonstrates how metagenomic sequencing within a spatial epidemiology framework can be used to address questions surrounding AMR complexity in natural ecosystems.

scholarly journals Evaluation of Hydrogen Yield Evolution in Gaseous Fraction and Biochar Structure Resulting from Walnut Shells Pyrolysis

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6359
Author(s):  
Elena David
Keyword(s):  
Heating Rate ◽  
Pyrolysis Temperature ◽  
Walnut Shell ◽  
Hydrogen Yield ◽  
X Ray Diffraction ◽  
Fast Heating ◽  
X Ray ◽  
Walnut Shells ◽  
Water Vapors ◽  
Gaseous Fraction

Conversion experiments of wet and dry walnut shells were performed, the influence of moisture content on the hydrogen yield in the gas fraction was estimated and the resulted biochar structure was presented. Measurements of the biochar structures were performed using X-ray diffraction and scanning electron microscopy methods. The results demonstrate that heating rate played a key role in the pyrolysis process and influenced the biochar structure. Under fast heating rate, the interactions between the water vapors released and other intermediate products, such as biochar was enhanced and consequently more hydrogen was generated. It could also be observed that both biochar samples, obtained from wet and dry walnut shells, had an approximately smooth surface and are different from the rough surface of the raw walnut shell, but there are not obvious differences in shape and pores structure between the two biochar samples. The increasing of the biochar surface area versus pyrolysis temperature is due tothe formation of micropores in structure. The biochar shows a surface morphology in the form of particles with rough, compact and porous structure. In addition the biochar structure confirmed that directly pyrolysis of wet walnut shells without predried treatment has enhanced the hydrogen content in the gas fraction.

Mechanism of Hg(II), Cd(II) and Pb(II) ions sorption from aqueous solutions by Aspergillus niger spores

2019 ◽  
Vol 55 (5) ◽  
pp. 848-859
Author(s):  
Han Cui ◽  
Xiang Liu ◽  
Kun Li ◽  
Ting-Ting Cao ◽  
Chongwei Cui ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Aqueous Solutions ◽  
Sorption From Aqueous Solutions

Effective removal of Cr(vi) using β-cyclodextrin–chitosan modified biochars with adsorption/reduction bifuctional roles

RSC Advances ◽  
2016 ◽  
Vol 6 (1) ◽  
pp. 94-104 ◽  
Author(s):  
Xixian Huang ◽  
Yunguo Liu ◽  
Shaobo Liu ◽  
Xiaofei Tan ◽  
Yang Ding ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Aqueous Solutions ◽  
Low Cost ◽  
Walnut Shell ◽  
Beta Cyclodextrin ◽  
Effective Removal ◽  
Adsorption Reduction

In this work, beta-cyclodextrin–chitosan modified walnut shell biochars (β-CCWB) were synthesized as a low-cost adsorbent for the removal of heavy metal Cr(vi) from aqueous solutions.

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