Abstract Self compacting concrete (SCC) is a new construction material in the world. The aim of this research is to construct self compacting concrete with high compressive strength using combination of nano silica and micro silica. For this purpose, nano silica, micro silica, Portland cement type 2, superplasticizer (SP), and gravel and sand have been used. Three different groups of samples wi...

In this study two series of self compacting concrete mixtures were prepared with 100% coarse recycled concrete aggregates and different percentages of 0%, 20%, 40%, 60%, 80% and 100% fine recycled concrete aggregates. In series I and II the water to binder ratios were 0.50 and 0.45, respectively. The cement content was kept 350 3 m kg for those mixtures that don't have any Nano-Silica. To impro...

in this investigation, nano silica chloride (nano sio2cl) has been found to be efficient, chemoselective and recyclable catalyst for facile and simple synthesis of germinal diacetates from aromatic and heteroaromatic aldehydes in shorter reaction durations. the products were obtained in high to excellent yields. this work consistently has the advantages of excellent yields, short reaction time,...

The acid-catalyzed synthesis of highly ordered mesostructured materials has led to a variety of twoand three-dimensional periodic symmetries, and has proven to be an effective route for the generation of fibers, spheres, thin films, and other monolithic forms of mesoporous materials. Zhao et al. recently used non-ionic poly(alkylene oxide) block copolymers, under acidic conditions, to prepare w...

Silica nanoparticles were synthesized by chemical methods from tetraethylorthosilicate (TEOS), polyethylene glycol 5% and hydrochloric acid 0.001 N. The sol-gel process was applied for the preparation of nano silica gel. This method is hydrolysis and condensation reactions of TEOS as precursor of silica. The optimal synthesis conditions for the preparation of silica nanoparticles were obtained ...

in the recent years, rapid growth of the world’s population and overutilization of fresh water resources have caused fresh water shortage crisis in the world. in spite of the agricultural activities in the northern beaches of iran and also severe decrease of the ground water level, it still has not taken any effective measures to desalinate caspian sea water in large scale. in this research, de...

The self-assembly and sol-gel polymerisation of novel alkoxysilane-functionalized polymethylsiloxanes provide versatile access to nano-assembled containers, silica-based micro- and nano-architectures and dispersed mixed metal oxide hybrid materials.

In order to improve the erosion capacity of a supercritical carbon dioxide (SC-CO2) jet, the influence of a nano-silica additive on the rock erosion characteristics was experimentally investigated. By impinging the SC-CO2 jets with nano-silica mass fractions of 0 wt % (pure SC-CO2 jet), 3 wt %, 6 wt %, 9 wt %, 12 wt %, 15 wt %, and 18 wt % on specimens of red sandstone, the erosion volumes unde...

A new, efficient method for the synthesis of 2-aryl substituted benzimidazole by using silica supported periodic acid (H5IO6-SiO2) as a catalyst has been developed. The salient feature of the present method includes mild reaction condition, short reaction time, high yield and easy workup procedure. The synthesized benzimidazoles exhibited potent anticancer activity against MCF7 and HL60 cell li...

Hybrid micro-/nano-silica architectures made of bacterial-body-templated silica shell attached with fimbriae-templated silica nanotubes were prepared by using living fimbriaed bacteria E. Coli TG1 as templates, which can function as individual bioreactors to catalyze the hydrolysis of 4-nitrophenyl-beta-d-galactopyranoside to form p-nitrophenol due to the presence of an intracellular enzyme.