The effects of adding Nano-Silica particles on the compressive strength and water permeability of concrete and its comparison with that of Micro-Silica were investigated in this work. The effect of combination of Nano- silica and Micro-silica were also studied in this work, which resulted in an increase in compressive strength of concrete in comparison with other concrete specimens tested in th...

in recent years, using sol-gel procedure for the purpose of laboratory and industrial synthesis of nano-structures, and especially silica nano-particles, has been significantly increased. in this research, silica particles were synthesized by sol-gel procedure and their physical and chemical properties were studied by means of scanning electron microscopy (sem), transmission electron microscopy...

High-resolution scanning electron microscopy (HR-SEM) with backscattered electrons (BSE) under a low accelerating voltage provided images with compositional information about Pt nano-particles with a diameter of approximately 6 nm that were dispersed in mesoporous silica (SBA-15). The dispersion of Pt nano-particles in mesoporous silica was investigated using the BSE imaging method in combinati...

There has always been a fascination with "impossible" compounds, ones that do not break any rules of chemical bonding or valence but whose structures are unstable and do not exist. This instability can usually be rationalized in terms of chemical or physical restrictions associated with valence electron shells, multiple bonding, oxidation states, catenation, and the inert pair effect. In the pu...

With nanotechnology becoming widely used, many applications such as plasmonics, sensors, storage devices, solar cells, nano-filtration and artificial kidneys require the structures with large areas of uniform periodic nanopatterns. Most of the current nano-manufacturing techniques, including photolithography, electron-beam lithography, and focal ion beam milling, are either slow or expensive to...

Structural preservation of complex biological systems from the subcellular to whole organism level in robust forms, enabling dissection and imaging while preserving 3D context, represents an enduring grand challenge in biology. Here we report a simple immersion method for structurally preserving intact organisms via conformal stabilization within silica. This self-limiting process, which we ref...

The current essay analyzes the anti-corrosion properties of epoxy primers including anti-corrosion pigment calcium hydrogen orthophosphate and hydrophobic nano silica with various percentages optimized by Taguchi experimental design. The impact of influential factors such as the percentage of anti-corrosion pigments, percentage of nano silica and pigment to binder ratio on anti-corrosion proper...

Nanofibrous membranes, consisting of a poly(L-lactic acid) (PLLA)-silica xerogel hybrid material, were successfully fabricated from a hybrid sol using the electrospinning technique for guided bone regeneration (GBR) application. These hybrid nanofibers exhibited a homogeneous and continuous morphology, with a nano-sized dispersed silica xerogel phase in the PLLA fiber matrix. The mechanical pro...

A new concept of designing and synthesizing highly dispersed ionic liquids was developed through physical confinement or encapsulation of them into silica gel matrix with sol-gel process. A series of silica gel confined ionic liquids were synthesized through this process and characterized by diffuse-reflectance infrared Fourier transform spectroscopy (DRIFTS) and FTRaman analysis, and abnormal ...

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 ...