glycerol mono-oleate (gmo) was produced by direct esterification reaction with amberlyst 16 resin catalysts with the efficiency of 86% and was used as a surfactant for synthesis of cofe2o4 nano-particles by surfactant-assisted microwave method. fourier transform infrared spectroscopy (ft-ir), x-ray diffraction (xrd) and scanning electron microscopy (sem) were used to consider the structural and...

Various antibacterial fluoroquinolone compounds were prepared by the direct amination of 7-halo-6- fluoroquinolone-3-carboxylic acids with variety of piperazine derivatives and (4aR,7aR)-octahydro-1H-pyrrolo[3,4-b] pyridine using Zirconia Sulfuric Acid (ZrSA) nanoparticle, as a catalyst in refluxing water. The results showed that ZrSA exhibited high catalytic activity towards the synthesis of f...

Novel technical solutions and ideas for increasing the yield of solar semiconductor grade polycrystalline silicon processes have been analyzed. The predominant technology is currently still Siemens process including conversion (synthesized by carbon-thermal reduction quartzites) to trichlorosilane followed rectification hydrogen reduction. cost product can be cut down reducing synthesis costs t...

A low-power ROM-less Direct Digital Frequency Synthesis (DDFS) system that exceeds the spectral purity of existing low-power DDFS systems by approximately is presented. The design applies an analogue voltage to the CMOS differential current switch in one cell of a non-linear DAC to interpolate between the output values which would be available from a conventional non-linear DAC.

A 1 0-step synthesis of hydroxysemperoside deglucoside has been achieved. The key step is an organopalladium-mediated cyclization that produces a highly functionalized oxabicyclooctane. The remaining functional groups are introduced by addition to the exo face of the fused bicyclic system.

The importance and increased demand of pharmaceutically active azaheterocycles has urged the development of inexpensive and environmentally benign catalytic asymmetric technologies. 2] In this context, the pyrazolidine and pyrazoline structural motif is present in several compounds with significant bioactivities, such as anti-inflammatory, antidepressant, anticancer, antibacterial and antiviral...

There are now a number of methods available for generating synthetic sound based on physical models of wind instruments, including digital waveguides, wave digital filters, impedance-based methods and those involving impulse responses. Normally such methods are used to simulate the behaviour of the resonator, and the coupling to the excitation mechanism is carried out by making use of simple lu...

We demonstrate a laser-based technique to directly synthesize few layer graphene on quartz substrates without using any metal catalyst. In our approach, a photoresist S-1805 (from Shipley Comp.) film coated on quartz wafers was heated, and then decomposed, by irradiation of a continuous-wave laser. The carbon atoms from the photoresist were dissolved in the molten quartz, and then extracted to ...