Nanosilica periodic acid (nano-SPIA) is found to be a new, powerful, and reusable heterogeneous catalyst for the rapid synthesis of 2-naphtholazo dyes via diazotization of aromatic amines and followsazo coupling with 2-naphthol under solvent-free conditions at room temperature by grinding. Eco-friendly, heterogeneous reaction conditions, high stability of diazonium salt, simple experimental pro...

nanosilica periodic acid (nano-spia) is found to be a new, powerful, and reusable heterogeneous catalyst for the rapid synthesis of 2-naphtholazo dyes via diazotization of aromatic amines and followsazo coupling with 2-naphthol under solvent-free conditions at room temperature by grinding. eco-friendly, heterogeneous reaction conditions, high stability of diazonium salt, simple experimental pro...

an efficient and environmentally benign   method for the synthesis of aryl iodides have been developed by diazotization of aromatic amines with nano2 and nanosilica periodic acid (nano-spia) as a green catalyst via grinding followed by a sandmeyer iodination by ki under solvent-free conditions at room temperature. the ensuing aryl diazonium salts supported on nano-spia were sufficiently stable ...

An efficient and environmentally benign   method for the synthesis of aryl iodides have been developed by diazotization of aromatic amines with NaNO2 and nanosilica periodic acid (nano-SPIA) as a green catalyst via grinding followed by a sandmeyer iodination by KI under solvent-free conditions at room temperature. The ensuing aryl diazonium salts supported on nano-SPIA were sufficiently stable ...

Polymer nanocomposites are increasingly used in applications that are subjected to harsh environments. Owing to polymer's susceptibility to photodegradation, nanofillers in a polymer nanocomposite may be released into the environments during the composite's life cycle. Such release potentially poses an environmental health and safety problem and may hinder commercialization of these advanced ma...

We compared the acute toxicity of nanosilica and polyacrylate/nanosilica instillation in Wistar rats (n = 60). Exposure to nanosilica and polyacrylate/nanosilica showed a 30% mortality rate. When compared with saline-treated rats, animals in both exposure groups exhibited a significant reduction of PO2 (P < 0.05) at both 24 and 72 hr. after exposure. Both exposure groups exhibited a significant...

Recently, nanomaterials (such as nanosilica) are receiving special attention because of their ability to improve the performance of concrete compared with traditional mineral admixtures. In this work, a number of specimens were prepared to study the behavior of cement mortar containing nanosilica. The cement replacement by nanosilica of 3% and 5% by weight of cement was used. The mechanical and...

Nanosilica is one of the most widely used nanomaterials across the world. However, their assessment data on the occupational exposure to nanoparticles is insufficient. The present study performed an exposure monitoring in workplace environments where synthetic powders are prepared using fumed nanosilica. Furthermore, after it was observed during exposure monitoring that nanoparticles were emitt...

In this study, filler and silica fume were substituted by Liquid crystal display glass powder (LCDGP) nanosilica, respectively, to improve the performance of ultra-high- fiber-reinforced concrete. addition, surface steel fiber was modified with ethylenediaminetetraacetic acid (EDTA) solution interfacial friction between Ultra-high-performanceconcrete (UHPC) matrix. Both LCDGP nanosilica reacted...

heterogeneous proton exchange membranes (pem) are synthesized using the dry phase inversion technique. the casting solutions are prepared by dispersing a finely ground cation exchange resin particle in n,n-dimethylacetamide (dmac) solution of polyvinyl-chloride (pvc). results show that ion exchange capacity is increased with the addition of 1 %-wt nanosilica (from 0.14 to 0.27 meq/g) while it i...