knoevenagel condensation between barbituric acid and aldehyde was investigated in the presence of sulfonic acid functionalized nanoporous silica (sba-pr-so3h) and resulted in the formation of arylidene and bis-arylidene barbiturates. excellent yields and short reaction times are related to the high efficiency of sba-pr-so3h that the reactions take place easily in its nano-pores. sba-pr-so3h as ...

This paper describes the synthesis and chromatographic and morphologic characterization of two monolithic silica nano-columns (50 µm i.d.) prepared by sol-gel processes, using hydrophilic interaction (HILIC) mode separations to evaluate their performance. Two types of monoliths were prepared by varying the precursors (tetraethoxysilane or a tetraethoxysilane-methyltrimethoxysilane mixture) and ...

In this paper, a planar monopole antenna is introduced, also we added some new Nano fillers such as Fumed Silica and Aluminum Oxide to RT Duriod5880 and RO3003 to produce new Nano composite materials, then new Nano composite materials are used as a substrate of a ultra-wideband monopole antenna. Antenna characteristics are considered to illustrate that, by using these Nano composite materials, ...

In crude oil, asphaltene is one of the fractions that may be dissolved in aromatics like benzene or toluene but cannot alkanes n-heptane, n-pentane, petroleum ether (a mixture alkane compounds). A typical difficulty oil recovery and refinery processes precipitation, which happens when stream's pressure, composition, temperature change. So, stability needs to looked at find out how likely it for...

This study is focused on synthesis of nano-colloidal silica via alkaline water glass solution. Sodium ions of water glass were removed by cation exchanging in a resin column to obtain the silicic acid which was titrated to the solution of sodium silicate. Concentration of the colloidal silica and pH value of the solutions were controlled using different concentrations of alkaline sodium silicat...

Use of high numerical aperture focusing with negative longitudinal spherical aberration is shown to enable deep (> microm), high aspect ratio, nano-scale-width holes to be machined into the surface of a fused-silica (SiO(2)) substrate with single pulses from a 200 fs, 4 microJ Ti-Sapphire laser source. The depths of the nano-holes are characterized by use of a non-destructive acetate replicatio...

In its standard version, our BioPhotonics Workstation (BWS) can generate multiple controllable counter-propagating beams to create real-time user-programmable optical traps for stable three-dimensional control and manipulation of a plurality of particles. The combination of the platform with microstructures fabricated by two-photon polymerization (2PP) can lead to completely new methods to comm...

Chromatographic separation and detection of nonfluorescent molecules were integrated in a nanochannel. Our method, extended-nano chromatography realized high-performance separation using pressure-driven flow in a 100-nm scale nanochannel. A photothermal detector, differential interference contrast thermal lens microscope (DIC-TLM) was employed for detection of nonfluorescent samples. In particu...

This paper presents application of artificial neural network to develop model for predicting 28 days compressive strength of concrete with partial replacement of cement with nano-silica for which the data has been taken from various literatures. The use of nano-particle materials in concrete can add many benefits that are directly related to the durability of various cementitious materials, bes...