Vimalkumar, T V; Dr.Vijayakumar, K P(Cochin University of Science & Technology, August , 2011)
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Abstract:
In the present work we report the preparation details studies on ZnO thin films. ZnO
thin films are prepared using cost effective deposition technique viz., Chemical Spray
Pyrolysis (CSP). The method is very effective for large area preparation of the ZnO thin
film. A new post-deposition process could also be developed to avoid the adsorption of
oxygen that usually occurs after the spraying process i.e., while cooling. Studies were done
by changing the various deposition parameters for optimizing the properties of ZnO thin
film. Moreover, different methods of doping using various elements are also tried to
enhance the conductivity and transparency of the film to make these suitable for various
optoelectronic applications.
Description:
Department of Physics,
Cochin University of Science and Technology
Poulose Jacob,K; Sreela Sasi; Rekha, James K(IEEE, December 9, 2009)
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Abstract:
Decimal multiplication is an integral part of
financial, commercial, and internet-based computations.
This paper presents a novel double digit decimal
multiplication (DDDM) technique that offers low latency
and high throughput. This design performs two digit
multiplications simultaneously in one clock cycle. Double
digit fixed point decimal multipliers for 7digit, 16 digit and
34 digit are simulated using Leonardo Spectrum from
Mentor Graphics Corporation using ASIC Library. The
paper also presents area and delay comparisons for these
fixed point multipliers on Xilinx, Altera, Actel and Quick
logic FPGAs. This multiplier design can be extended to
support decimal floating point multiplication for IEEE 754-
2008 standard.
Description:
Nature & Biologically Inspired Computing, 2009. NaBIC 2009. World Congress on
A new group of compounds with composition (Ba5-xSrx) Nb4015, having high
permittivity and low loss have been prepared and characterized in the microwave
frequency region . X-ray diffraction studies showed that monophase compound
existed for all values of x from 0 to 5. Microwave dielectric properties such as
and c f showed smooth variation with x , while the unloaded quality factor (Qu)
showed remarkable improvement with x
Thomas, Baby; Sathianandan, K; Nampoori, V P N; Vallabhan, C P G; Ramachandran, T(American Institute of Physics, September , 1991)
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Abstract:
A high power Nz laser of the double-Blumlein type having a modified gas flow system,
electrode configuration, and discharge geometry with minimum inductance is described. By
incorporating a triggere’d-pressurized spark gap switch, arc-free operation was achieved
for a wide E/P range. The device gives a peak power in excess of 700 kW with a FWHM of
3 ns and an efficiency of 0.51%, which is remarkably high for a pulsed nitrogen laser
system. The dependence of output power on parameters such as operating pressure, voltage,
and repetition rate are discussed.
Sasi Kumar, P R; Harilal, S S; Nampoori, V P N; Vallabhan, C P G(Pramana, March , 1994)
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Abstract:
High resolution optogalvanic spectrum of the (11, 7) band in the first positive system
of nitrogen molecule has been recorded from 17179 to 17376 cm- 1. Assignment of 432 rotational
lines belonging to the 27 branches of this band has been carried out.
Sasi Kumar, P R; Ambadi, B; Nampoori, V P N; Vallabhan, C P G(Springer, February , 1993)
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Abstract:
Doppler limited high resolution spectrum in the wavelength region 17224 to 17236 cm−1 of the first positive system (B 3Π g −A 3Σ u + ) of the N2 molecule is recorded by optogalvanic spectroscopic technique using a single mode ring dye laser. It is observed that the intensity and line width of the rotational line increase with the discharge current. Dependence of the collision broadening coefficient on the current was also evaluated.
The paper presents a compact planar Ultra Wide Band ¯lter employing folded stepped
impedance resonators with series capacitors and dumb bell shaped defected ground structures. An
interdigital quarter wavelength coupled line is used for achieving the band pass characteristics. The
transmission zeros are produced by stepped impedance resonators. The ¯lter has steep roll o® rate and
good attenuation in its lower and upper stop bands, contributed by the series capacitor and defected
ground structures respectively.
Description:
Progress In Electromagnetics Research C, Vol. 49, 123{131, 2014
Thomas, Kurian; Jacob, Samuel; Thommachan, Xavier(Wiley Periodicals, December , 2001)
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Abstract:
High styrene rubber ionomers were prepared by sulfonating styrene–butadiene
rubber of high styrene content (high styrene rubber) in 1,2-dichloroethane using
acetyl sulfate reagent, followed by neutralization of the precursor acids using methanolic
zinc acetate. The ionomers were characterized using X-ray fluorescence spectroscopy,
Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance
spectroscopy (NMR), dynamic mechanical analysis (DMA), and also by the evaluation
of mechanical properties. The FTIR studies of the ionomer reveal that the sulfonate
groups are attached to the benzene ring. The NMR spectra give credence to this
observation. Results of DMA show an ionic transition (Ti) in addition to glass–rubber
transition (Tg). Incorporation of ionic groups results in improved mechanical properties
as well as retention of properties after three cycles of processing
Description:
Journal of Applied Polymer Science, Vol. 85, 2294–2300 (2002)
Subhadra, V K; Syamaprasad, U; Vallabhan, C P G(American Institute of Physics, 1983)
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Abstract:
Results of axiswise measurements of the electrical conductivity (dc and ac) and dielectric constant of NH4H2PO4 confirm the occurrence of the recently suggested high‐temperature phase transition in this crystal (at 133 °C). The corresponding transition in ND4D2PO4 observed here for the first time takes place at 141.5 °C. The mechanism involved in these transitions and those associated with the electrical conduction and dielectric anomalies are explained on the basis of the motional effects of the ammonium ions in these crystals. Conductivity values for deuterated crystals give direct evidence for the predominance of protonic conduction throughout the entire range of temperatures studied (30–260 °C).