This paper presents the conceptual stages of simulation and development a modified transceiver antenna for high-power pulsed nuclear quadrupole resonance (NQR) detector explosives containing 14N isotope. At frequency 4.645 MHz, better characteristics are obtained using nine-turn coil shaped as half Fermat spiral with an outer radius 75 mm. Using COMSOL Multiphysics numerical parametric material...

Detection of explosives has the flavor of those mathematical problems that are not invertible. It is easier to hide explosives than to find them. Many approaches have been proposed and executed for the remote detection of explosives, contraband materials, weapons of mass destruction, currency, etc. Most detection technologies suffer from a common problem: the features they look for, such as dis...

Hole burning, which is attributed to optical pumping of nuclear-quadrupole levels, has been observed in the stoichiometric rare-earth compound, EuP5O14 . The long lifetime of these holes (-60 min) implies slow nuclear-spin flip-flop rates. The small magnetic moment of Eu3+ has prevented conventional magnetic-resonance measurements on Eu3+ compounds, but hole burning provides a sensitive method ...

We present ab initio Hartree-Fock lattice calculations on a series of heterocyclic and other compounds. Some of these have previously been studied by cluster calculations with the same D Z basis sets at the SCF level. The electric field gradients at the nitrogen centres, are related to NQR experimental determinations of nuclear quadrupole coupling constants. The compounds studied include imidaz...

High pressure technique applied in studies of NQR frequency and quadrupole relaxation has been used for deriving information on the dynamical properties of crystals and the nature of their phase transitions. The ^Cl NQR pressure studies have been carried out and a detailed analysis is given for the following topics: 1) Symmetric and asymmetric hydrogen bonded systems under high pressure. 2) NQR...

The dc SQ U ID (Superconducting QUantum Interference Device) can be configured as an ampli­ fier of spin-echos with a noise temperature of approximately 10 mK (f/1 MHz) at an operating temperature of 1.5 K. A Fourier transform spectrometer based on a SQ U ID with a superconducting input circuit and operated in a flux-locked loop is used to obtain nuclear quadrupole resonance (NQR) spectra in a ...

N nuclear quadrupole resonance of the system (NaN02)i_J(AN03)A. with A = K and Na in the x-range 0<x<0.5 and the temperature range 77 K < 7 < 3 6 0 K has been studied. The l N NQR frequency of NaN0 2 and its line width do not change with x, the latter fact untrasting the results of other mixed systems such as Na|_,.AgvN02. This indicates that in (NaN02)!_v(AN03)v highly mobile lattice defects e...