The effect of different parameters including: nano silica content, curing temperature, type of hardener, and flash-off time on mechanical and optical properties of polyurethane PU based clearcoat was investigated via standard Taguchi L9 method. Dispersion of nano silica in the resultant nanocomposites was explored by scanning electron microscopy SEM. SEM images showed a fine dispersion through ...

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,...

Ferric Species Standard ferric sulfate solutions were prepared by dissolving spectrographically pure iron rod (Johnson Matthey) in sulfuric acid and oxidizing with hydrogen peroxide. The decadic molar extinction coefficient of ferric ion in 0.8 N sulfuric acid at 24.9?C was found to be 2199 ? 4 liters mole-' cm-l at 304 m,/. The effect of a decrease of acidity and of added ferrous and cupric su...

Sulfuric acid is widely recognized as a very important substance driving atmospheric aerosol nucleation. Based on quantum chemical calculations it has been suggested that the quantitative detection of gas phase sulfuric acid (H2SO4) by use of Chemical Ionization Mass Spectrometry (CIMS) could be biased in the presence of gas phase amines such as dimethylamine (DMA). An experiment (CLOUD7 campai...

Natural fibers such as kenaf have been studied extensively as a reinforcing phase and received major attention recently due to their renewability, biodegradability, and high strength comparable to other synthetic fibers. In this study, nano-crystalline cellulose (NCC) was produced from kenaf core wood using the acid hydrolysis method. Kenaf core was alkali treated with a 4 wt% of sodium hydroxi...

Abstract Acid mine drainage is the reaction of surface water with sub-surface located on sulfur bearing rocks, resulting in sulfuric acid. These highly acidic conditions result leaching non-biodegradeable heavy metals from rock which then accumulate flora, posing a significant environmental hazard. Hence, reliable, cost effective remediation techniques are continuously sought after by researche...

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 ...