Non-woven polypropylene fabric modified with carbon nanotubes and decorated with nanoakaganeite for arsenite removal

Due to its harmful impact on human health, the presence of heavy metals, metalloids and other toxic pollutants in drinking or irrigation water is a major concern. Recent studies have proved that nanosized adsorbents are significantly more effective than their microsized counterparts. Particular attention has been given to nanocomposites with nanoadsorbents embedded in matrixes that could provide stability to the material and contribute to eliminating problems that may appear when using conventional granular systems. This study presents the preparation of a novel hybrid filter from a commercially available polypropylene (PP) non-woven fabric matrix modified with multiwall carbon nanotubes (MWCNT) and iron oxy(hydroxide) nanoparticles, and its use in the removal of As(III). A Box–Behnken statistical experimental design has been chosen to explore relevant variables affecting the filter performance: (1) As(III) concentration, (2) pH and (3) sorbent dose. From an As(III) concentration of 10 mg L−1, at pH 6.5 and with a sorbent dose of 5 g L−1, the PP filter modified with MWCNT removes 10% of the initial metalloid concentration, reaching a capacity of 0.27 mg g−1. After modification with iron oxy(hydroxide), the performance of the material is largely enhanced. The filter, under the same conditions, removes 90% of the initial As(III) concentration, reaching a capacity almost tenfold higher (2.54 mg g−1). This work demonstrates that the developed hybrid filter is effective toward the removal of As(III) in a wide range of pHs. A cubic regression model to compute the removal of the filter as a function of pH and sorbent dose is provided.acceptedVersio

New insights into Plagiogrammaceae (Bacillariophyta) based on multigene phylogenies and morphological characteristics with the description of a new genus and three new species.

Plagiogrammaceae, a poorly described family of diatoms, are common inhabitants of the shallow marine littoral zone, occurring either in the sediments or as epiphytes. Previous molecular phylogenies of the Plagiogrammaceae were inferred but included only up to six genera: Plagiogramma, Dimeregramma, Neofragilaria, Talaroneis, Psammogramma and Psammoneis. In this paper, we describe a new plagiogrammoid genus, Orizaformis, obtained from Bohai Sea (China) and present molecular phylogenies of the family based on three and four genes (nuclear-encoded large and small subunit ribosomal RNAs and chloroplast-encoded rbcL and psbC). Also included in the new phylogenies is Glyphodesmis. The phylogenies suggest that the Plagiogrammaceae is composed of two major clades: one consisting of Talaroneis, Orizaformis and Psammoneis, and the second of Glyphodesmis, Psammogramma, Neofragilaria, Dimeregramma and Plagiogramma. In addition, we describe three new species within established genera: Psammoneis obaidii, which was collected from the Red Sea, Saudi Arabia; and Neofragilaria stilus and Talaroneis biacutifrons from the Mozambique Channel, Indian Ocean, and illustrate two new combination taxa: Neofragilaria anomala and Neofragilaria lineata. Our observations suggest that the biodiversity of the family is strongly needed to be researched, and the phylogenetic analyses provide a useful framework for future studies of Plagiogrammaceae

<i>Cymatosirella</i> Dabek, Witkowski & Sabbe gen. nov., a new marine benthic diatom genus (Bacillariophyta) belonging to the family Cymatosiraceae

We present a new marine benthic diatom genus Cymatosirella gen. nov. The genus belongs to the family Cymatosiraceae and has been assigned to the subfamily Extubocelluloideae on the basis of ultrastructural cell wall features. It has isovalvate cells with undulate valves and is characterized by the absence of tubular processes and the occurrence of hollow spines which are observed for the first time in the Cymatosiraceae. The new genus contains four species, two of which are transferred from the genus Cymatosira, viz. Cymatosirella capensis comb. nov. and Cymatosirella minutissima comb. nov., and two which are new to science, viz. Cymatosirella benguelensis sp. nov. and Cymatosirella taylorii sp. nov. Cymatosirella capensis is chosen as the generitype. The new genus includes a group of very small taxa inhabiting the intertidal zone of the Atlantic Ocean with three species in South Africa and one in Europe. C. capensis was originally described by Giffen from Langebaan Lagoon (a shallow marine inlet in the southern part of Saldanha Bay, Western Cape Province), on the basis of light microscopy only, and has to date only been illustrated by line drawings. C. minutissima, so far only known from the Westerschelde estuary (The Netherlands), has previously been documented in more detail using both light and electron microscopy. Here, we present the results of detailed light and electron microscopical investigations of C. capensis, both from its original type material and from recently collected samples from the type locality and neighboring littoral areas in the Western Cape Province, and of the new species C. benguelensis and C. taylorii, also from Western Cape localities. All species are compared with similar small taxa belonging to the Cymatosiraceae, subfamily Extubocelluloideae

Non-woven polypropylene fabric modified with carbon nanotubes and decorated with nanoakaganeite for arsenite removal

Due to its harmful impact on human health, the presence of heavy metals, metalloids and other toxic pollutants in drinking or irrigation water is a major concern. Recent studies have proved that nanosized adsorbents are significantly more effective than their microsized counterparts. Particular attention has been given to nanocomposites with nanoadsorbents embedded in matrixes that could provide stability to the material and contribute to eliminating problems that may appear when using conventional granular systems. This study presents the preparation of a novel hybrid filter from a commercially available polypropylene (PP) non-woven fabric matrix modified with multiwall carbon nanotubes (MWCNT) and iron oxy(hydroxide) nanoparticles, and its use in the removal of As(III). A Box–Behnken statistical experimental design has been chosen to explore relevant variables affecting the filter performance: (1) As(III) concentration, (2) pH and (3) sorbent dose. From an As(III) concentration of 10 mg L−1, at pH 6.5 and with a sorbent dose of 5 g L−1, the PP filter modified with MWCNT removes 10% of the initial metalloid concentration, reaching a capacity of 0.27 mg g−1. After modification with iron oxy(hydroxide), the performance of the material is largely enhanced. The filter, under the same conditions, removes 90% of the initial As(III) concentration, reaching a capacity almost tenfold higher (2.54 mg g−1). This work demonstrates that the developed hybrid filter is effective toward the removal of As(III) in a wide range of pHs. A cubic regression model to compute the removal of the filter as a function of pH and sorbent dose is provided

Insight into diatom frustule structures using various imaging techniques

The diatom shell is an example of complex siliceous structure which is a suitable model to demonstrate the process of digging into the third dimension using modern visualization techniques. This paper demonstrates importance of a comprehensive multi length scale approach to the bio structures materials with the usage of state of the art imaging techniques. Imaging of diatoms applying visible light, electron and X ray microscopy provide a deeper insight into the morphology of their frustule

on Focused Ion Beam nanocuts

The marine diatom Olifantiella Riaux-Gobin et Compere predominantly occurs in tropical Indo-Pacific coral reef environments. The genus has about a dozen validly published taxa and is characterized by transapically elongate striae composed of a macroareola, broad perforated girdle, and tubular buciniportula process of trumpet-shape. The valve mantle of taxa related to the generitype, O. mascarenica, have a canal- shaped structure around the valve at the face / mantle junction, while those to O. gorandiana have a simple mantle or strongly narrow canal and complex buciniportula composed of hollow processes. The geographic distribution of Olifantiella is expanded in this study to include species observed in loggerhead sea turtles scrapes from the Aegean Turkish coast and samples from the Turkish Black Sea and Adriatic Sea coasts. Olifantiella has also been identified in Martinique Island, Caribbean Sea. A transfer of Navicula infirmitata is proposed due to the areola and buciniportula structure, as Olifantiella infirmitata. Further, an application of the Focused Ion Beam (FIB) to a sequential cutting of frustules allows resolution of Olifantiella mascarenica valve ultrastructure

AN OVERLOOKED GENUS "OLIFANTIELLA C. RIAUX-GOBIN & COMPERE". EXPANDING

Tristan Richmond Temple High Schoolhttps://dc.swosu.edu/barkpic16/1138/thumbnail.jp