1,021 research outputs found
Shape Invariant Potential and Semi-Unitary Transformations (SUT) for Supersymmetric Harmonic Oscillator in T4-Space
Constructing the Semi - Unitary Transformation (SUT) to obtain the
supersymmetric partner Hamiltonians for a one dimensional harmonic oscillator,
it has been shown that under this transformation the supersymmetric partner
loses its ground state in T^{4}- space while its eigen functions constitute a
complete orthonormal basis in a subspace of full Hilbert space.
Keywords: Supersymmetry, Superluminal Transformations, Semi Unitary
Transformations.
PACS No: 14.80L
Generalized Electromagnetic fields in Chiral Medium
The time dependent Dirac-Maxwell's Equations in presence of electric and
magnetic sources are written in chiral media and the solutions for the
classical problem are obtained in unique simple and consistent manner. The
quaternion reformulation of generalized electromagnetic fields in chiral media
has also been developed in compact, simple and consistent manner
Ferromagnetism and ferroelectricity in highly resistive Pb(0.7)Sr(0.3)(Fe(0.012)Ti(0.988))O(3) nanoparticles and its conduction by variable-range-hopping mechanism
The enhancement in ferromagnetism and ferroelectricity at room temperature for Pb0.7Sr0.3�Fe0.012Ti0.988�O3 �PSFT� nanoparticles is proved by magnetization and polarization
hysteresis loop. The x-ray diffraction and micrograph show that the PSFT nanoparticles have distorted tetragonal single phase, and their average particle’s size is 8 nm. The effect of Sr content reduces the particle size, and hence the multiferroic system becomes more resistive, which
dominates the superparamagnetic/paraelectric relaxation. The variable-range-hopping conduction mechanism explained the high resistivity of PSFT nanoparticles, which suggests that the room temperature movement of electrons involves short-range order through defect states
Nanotechnology Applications for Chemical and Biological Sensors
Recent discoveries indicate that when the materials are brought down to sizes in the range 1–100 nm, theseexhibit unique electrical, optical, magnetic, chemical, and mechanical properties. Methods have now beenestablished to obtain the monodisperse nanocrystals of various metallic and semiconducting materials, single-walled and multi-walled nanotubes of carbon and other metallic and non-metallic materials together withorganic nanomaterials such as supra-molecular nanostructures, dendrimers, hybrid composites with tailoredfunctionalities. The high surface-to-volume ratio with an added element of porosity makes these highly potentialcandidates for chemical and biological sensor applications with higher degree of sensitivity and selectivity ascompared to their bulk counterparts. The paper reviews the recent developments and applications of chemicaland biological sensors based on nanomaterials of various structural forms.Defence Science Journal, 2008, 58(5), pp.636-649, DOI:http://dx.doi.org/10.14429/dsj.58.168
Analysis of MAGSAT data of the Indian region
Progress in the development of software for reading MAGSAT data tapes and for the reduction of anomaly data, and in the preparation of data for magnetic anomaly maps is reported
Piezoelectric Properties of Ta (≤ 5 (mole)%) Doped in Na0.685K0.315NbO3
To explore the piezoelectric potential of Ta doping on the MPB- like composition Na0.685K0.315NbO3, ceramic pellets of Na0.685K0.315Nb1-yTayO3 (y ≤ 0.05) were arranged by solid-state reaction method. For piezoelectric measurements, sintered pellets were electroded, in parallel capacitor configuration, with silver coating deposited by direct current (dc) magnetron sputtering of a silver target. Polarization and piezoelectric parameters were measured using a ferroelectric (PE- loop tracer) and piezo- meter (AixACCT Systems, GmbH). Composition (y) variation of remnant polarization, coercive field, converse piezoelectric coefficient (d*33), and polarization current measurements were carried out in the prepared compositions. The remnant polarization (Pr) is 18.439 μC/cm2 with a coercive field (Ec) of 8 kV/cm for NKNT single crystals. d*33 was observed 300.76 pm/V for y = 0.04 at the applied field of 22kV/cm
Electrical Properties of lead free ceremics Na1−XKxNbO3, at x=0.305.
By solid state reaction method, ceramic pellets of Na0.695K0.305NbO3 have been prepared. X-ray- diffraction, Piezo properties, scanning electron microscope, and temperature dependence of dielectric constant and loss tangent of the prepared samples have been studied. It has been observed that, at the transition temperature, dielectric constant peak shifts to lower temperature, and the dielectric constant and loss tangent peak heights decrease, with increasing frequency, and show three structural phase transitions
Dielectric properties of Na1−xKxNbO3, near x = 0.475 morphotropic phase region
11-17Sodium-potassium niobate (Na1−xKxNbO3) ceramic pellets, with x = 0.465, 0.470, 0.475, 0.480 and 0.485, were prepared by solid state reaction method with double sintering. With varying composition (x), the dielectric properties, X-ray diffraction peaks shifting pattern, in this system. Among the prepared compositions, a break in the X-ray diffraction peaks shifting tendency; minimum dielectric constant, loss tangent and dielectric conductivity indicate a morphotropic phase transition type behavior, at the composition with x = 0.475
Electrical Properties of lead free ceremics Na1−XKxNbO3, at x=0.305.
783-786By solid state reaction method, ceramic pellets of Na0.695K0.305NbO3 have been prepared. X-ray- diffraction, Piezo properties, scanning electron microscope, and temperature dependence of dielectric constant and loss tangent of the prepared samples have been studied. It has been observed that, at the transition temperature, dielectric constant peak shifts to lower temperature, and the dielectric constant and loss tangent peak heights decrease, with increasing frequency, and show three structural phase transitions
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