PULSAR DETECTION SYSTEM USING RADIO TELESCOPE

Radio astronomers and Researchers have detected numerous neutron stars in our galaxy, and they also predicted the Existence of many more neutron stars in space. Pulsars are very peculiar, yet almost inscrutable celestial objects. This is an object which is impelling radiation into space closest to the speed of light. Neutron stars are the most interesting galactic bodies to mankind. The things that hold us during the whole study are the fascinating properties of pulsar i.e. high density, a small diameter, strong gravity, and strong magnetic field. As the peculiar properties and the extreme nature of pulsar continue to disclose this catches the attention of Astronomers. Pulsars are distant objects. So, it is very tedious job to capture the radiations coming from it for this we have designed a system which consist of an Antenna, Filters, Amplifiers and Receiver. The signal we capture through the antenna will undergo signal processing to extract the Pulse which is buried in noise. The techniques used here are the fast-folding algorithm (FFA) and Fast Fourier transform (FFT) are explained along. By this whole study to building a system and performed signal processing and obtained the Pulse

Effect of nanosilica-based activators on the performance of an alkali-activated fly ash

This paper assesses the effect of the use of an alternative activator based on nanosilica/MOH (M = K+ or Na+) blended solutions on the performance of alkali-activated fly ash binders. Binders produced with commercial silicate activators display a greater degree of reaction, associated with increased contents of geopolymer gel; however, mortars produced with the alternative nanosilica-based activators exhibited lower water demand and reduced permeability, independent of the alkali cation used. Na-based activators promote higher compressive strength compared with K-based activators, along with a refined pore structure, although K-activated samples exhibit reduced water demand. Zeolite type products are the major crystalline phases formed within these binders. A wider range of zeolites is formed when using commercial silicate solutions compared with the alternative activators. These results suggest that there are variations in the availability of Si in the system, and consequently in the alkalinity, depending on the silicate source in the activator, which is important in determining the nanostructure of the geopolymer gel.This study was sponsored by the Ministerio de Ciencia e Innovacion of Spain (Project GEORES MAT2010-19934 and research scholarship BES-2008-002440), European regional development fund (FEDER), and the Universitat Politecnica de Valencia (Spain). The participation of SAB and JLP was funded by the Australian Research Council (ARC), including partial funding through the Particulate Fluids Processing Centre, a Special Research Centre of the ARC. A special acknowledgement is also due to the Centre of Electron Microscopy of the Universitat Politecnica de Valencia and Pedro Garces from the Universidad de Alicante for support in some experiments.Rodriguez Martinez, ED.; Bernal, SA.; Provis, JL.; Paya Bernabeu, JJ.; Monzó Balbuena, JM.; Borrachero Rosado, MV. (2013). Effect of nanosilica-based activators on the performance of an alkali-activated fly ash. Cement and Concrete Composites. 35(1):1-11. doi:10.1016/j.cemconcomp.2012.08.025S11135

Indentation Protocol to Determine Viscoelastic Properties of Cartilage before and after Crosslinking

Osteoarthritis affects millions of people of different age groups around the world. With very few treatment options and the highly restricted capacity of cartilage to repair, new treatment options are needed. The objective of this thesis was to develop a repeatable cartilage testing protocol, which could be used to test cartilage properties and determine if crosslinking can be used as a potential treatment for osteoarthritis. Previous studies have shown CASPc can be used as a photo-sensitizer to obtain collagen crosslinking through a secondary process. The ability to perform cartilage crosslinking by light-activation, which could be done arthroscopically is especially attractive as this would allow the surgery to be minimally invasive. The indentation protocol developed for a stress-relaxation test was able to achieve 95% repeatability, meaning the error in determining cartilage properties stayed within 5% of the average for tests performed at different times. Results of photo-chemical crosslinking demonstrated no change in cartilage stiffness when compared with control specimens. The spherical indenter chosen to indent the cartilage was suspected to apply less strain on cartilage as a result of its profile, which only compressed the cartilage instead of stretching its surface. The stiffness of CASPc control specimen was observed to be increasing when compared with no-CASPc control, as a result of added viscosity of CASPc solution. This elevated stiffness was observed to diminish over time due to the diffusion of CASPc from cartilage

Catalytic and electrocatalytic properties of intrazeolitically prepared iron phthalocyanine

Iron-phthalocyanine (FePc) has been successfully synthesised inside the pores of the NaY zeolite as evidenced by various physicochemical characterisation methods such as scanning electron microscopy (SEM), X-ray diffraction (XRD), electron spin resonance spectroscopy (ESR), ultraviolet spectroscopy (UV), cyclic voltammetry (CV) and thermal methods of analysis. XRD analysis indicates the formation of FePc molecules inside the supercages. SEM pictures show that the original microporous nature of NaY is not affected by encapsulation of FePc. ESR spectrum shows two peaks with g values of 1.977 and 4.030 indicating the partial oxidation of FePc in the cavity, while IR spectra suggest that the molecule can undergo a saddle deformation inside the zeolite matrix. In UV-Vis spectrum, the Q band of the FePc molecule is shifted from 656 nm to 686 nm, although the soret band is less affected. Thermal analysis indicates that these molecules have enhanced thermal stability inside the zeolite cavities. Cyclic voltammetric studies show that the electrochemical behaviour of pure FePc is not much affected by the encapsulation. The encapsulated FePc molecules are found to catalyse the hydrocarbon oxidation reactions. In addition, modified electrodes prepared with this material indicate good electrocatalytic effects as demonstrated by a 260 mV shift in the peak potential for oxygen reduction in neutral medium. Considerable electrocatalytic behaviour is also observed for oxidation of hydrazine

Aromatization of n-hexane over platinum alkaline ETS-10

The performance of Pt impregnated alkali metal exchanged ETS-10 as a bifunctional catalyst for the reforming of n-hexane has been examined in the temperature range of 673K to 773K at atmospheric pressure. A comparison of the activity of the above catalysts at the same conditions with Pt-Al2O3 has also been carried out. Pt-(alkaline)-ETS-10 samples exhibit greater aromatization activities than the Pt-Al2O3

Studies on the synthesis of ETS-10 II. Use of organic templates

ETS-10 has been synthesized using titanosilicate gels and organic templating agents such as choline chloride [OHCH2CH2(CH3)3N+Cl−] and the bromide salt of hexaethyl diquat-5 [Br−(C2H5)3N+(CH2)5N+(C2H5)3Br−]. The influences of temperature and concentration of the ingredients on the kinetics of synthesis are reported. Physicochemical characterizations of the samples have been carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and differential thermogravimetric analysis (DTA)/thermogravimetric analysis (TGA), and adsorption of water, n-hexane and mesitylene. The catalytic activities of H-ETS-10 in the dehydration of n-butanol and in the isomerization of m-xylene and 1,3,5-trimethylbenzene are reported

Cu<SUP>2+</SUP>-perchlorophthalocyanine immobilized MCM-41: catalyst for oxidation of alkenes

The immobilization of copperperchlorophthalocyanine (CuCl<SUB>16</SUB>Pc) complex in the channels of HSi-MCM-41 molecular sieves has been carried out by (i) post-synthesis in the presence of 3-aminopropyltriethoxysilane (3-APTES) and (ii) impregnation in the absence of 3-APTES. The resulting host-guest samples were characterized by XRD, MAS-NMR, nitrogen adsorption, IR and cyclic voltammetry. Each sample showed an IR band at 1390 cm<SUP>&#8722;1</SUP> suggesting the presence of CuCl<SUB>16</SUB>Pc complex in the channels of HSi-MCM-41. The results of the alkene epoxidation in presence of (i) TBHP and (ii) O<SUB>2</SUB>/isobutyraldehyde are compared. The oxo-metal and acyl peroxy radical species that formed predominantly using isobutyraldehyde give a high yield of epoxide, as compared to the reaction using TBHP as the oxidant

Beckmann rearrangement of cyclohexanone oxime over mesoporous Si-MCM-41 and Al-MCM-41 molecular sieves

Si-MCM-41 and Al-MCM-41 with different Al contents (Si/Al=43.9, 23.3 and 14.3) have been prepared using cetyl trimethylammonium bromide as an organic surfactant and characterised by XRD, MAS NMR and N2 sorption studies. The transformation of cyclohexanone oxime into &#949;-caprolactam has been studied over these molecular sieves. The influences of temperature and feed rate (WHSV) on the yield of caprolactam over the samples have been investigated at different times on stream. The studies reveal that activity and selectivity increase with Al content (investigated upto Si/Al=14) and maximum yield of &#949;-caprolactam is obtained at ~360 &#176;C