Dissolved silica species are naturally occurring, ubiquitous groundwater constituents with corrosion-inhibiting properties. Their influence on the performance and longevity of iron-based permeable reactive barriers for treatment of organohalides was investigated through long-term column studies using Connelly iron as the reactive medium. Addition of dissolved silica (0.5 mM) to the column feed ...

In this work, a robust synthetic pathway for magnetic core preparation and silica surface coating of magnetic microparticles is presented. Silica-coated magnetic particles are widely used to extract DNA and RNA from various biological samples. We present a novel route for the synthesis of iron oxide silica particles (Fe3O4@Silica) and demonstrate their performance for extracting ZIKA viral RNA ...

Bimodal nanoprobes comprising both magnetic and optical functionalities have been prepared via a sequential two-step process. Firstly, magnetite nanoparticles (MNPs) with well-defined cubic shape and an average dimension of 80 nm were produced by hydrolysis of iron sulfate and were then surface modified with silica shells by using the sol-gel method. The Fe₃O₄@SiO₂ particles were then functiona...

Archean Quartzose Rocks at Akilia, Greenland Fedo and Whitehouse (1) presented data to support their hypothesis that granulite grade quartz magnetite rocks on the island of Akilia, southwest Greenland—which are conformably interposed with pyroxenite and hornblendite units that date from before 3830 million years ago (Ma) (2–4)—had a metasomatic ultramafic igneous origin. They offered that inter...

Silica  coated magnetite  nanoparticles were  covalent  grafted with  3-aminopropyl trimethoxysilane  to give APTSCMNPs. Reaction of  the resulted nanomaterial with 4-formyl benzo-12-crown-4 ether afforded FB12C4/APTSMNPs  nanocomposite  material  in  which  the  crown ether  moiety  was  attached  through  propyl  chain  spacer. Characterization of  the prepared nanocomposite was performed wit...

We document the discovery of the first granular iron formation (GIF) of Archaean age and present textural and geochemical results that suggest these formed through microbial iron oxidation. The GIF occurs in the Nconga Formation of the ca. 3.0-2.8 Ga Pongola Supergroup in South Africa and Swaziland. It is interbedded with oxide and silicate facies micritic iron formation (MIF). There is a stron...

At present, the widespread use of iron oxide nanoparticles, including for commercial purposes, requires strict preservation their phase composition during application. The choice nanoparticle modifier and modification conditions is decisive due to high sensitivity oxygen in case using real (O2, pH change, etc.). In this work, we studied change magnetite nanoparticles after with 3-aminopropyltri...

Archean Quartzose Rocks at Akilia, Greenland Fedo and Whitehouse (1) presented data to support their hypothesis that granulite grade quartz magnetite rocks on the island of Akilia, southwest Greenland—which are conformably interposed with pyroxenite and hornblendite units that date from before 3830 million years ago (Ma) (2–4)—had a metasomatic ultramafic igneous origin. They offered that inter...

The performance requirements of the concrete of containment structures are mainly radiological protection, structural integrity and durability, etc. For this purpose, highperformance heavy density concrete with special attributes can be used. The aggregate of concrete plays an essential role in modifying concrete properties and the physico-mechanical properties of the concrete affect significan...

bis-(l-tyrosinato)copper(ii) was reacted with 3-(chloropropyl)-trimethoxysilane functionalized silica that has infused magnetite to yield a magnetically separable catalyst in which the copper carboxylate is covalently linked to the silica matrix through the silane linkage. the immobilized catalyst has been characterized by spectroscopic studies (such as ft-ir, epr, magnetic measurement, sem) an...