Off-Resonance Nutation NQR Spectroscopy of Powders

1995 ◽  
Vol 50 (10) ◽  
pp. 957-960 ◽  
Author(s):  
N.Ja. Sinjavsky
Keyword(s):  

Abstract The peculiarities of nutation NQR spectra of nuclei with spin I=3/2 in powders are considered in the case of a resonance offset. An equation, which takes into account the offset is given for the determination of the asymmetry η. It is shown that structural of monocrystals by means of nutation spectroscopy are possible.

1996 ◽  
Vol 51 (5-6) ◽  
pp. 363-367 ◽  
Author(s):  
Nicolai Sinyavsky ◽  
Michał Ostafin ◽  
Mariusz Maćkowiak

Abstract The method of two-dimensional nutation NQR spectroscopy, introduced by Harbison in 1989, has been successfully used for determining of the asymmetry parameter of the EFG tensor for spin-3/2 nuclei in both powdered and monocrystal samples in the absence of an external magnetic field. The inconvenience inherent in the method, however, is the long time required, because data acquisition must be repeated for various RF pulse lengths. We discuss a method to reduce the time of the nutation experiment by using a sequence of identical short RF pulses of length r w and distance τ. It is shown that for an NQR frequency ω0 , frequency offset Δω, and pulse parameters satisfying the relation ω0τ + Δωtw = 2πk (k = 1, 2, 3,..., n) a synchronism of pulse action takes place and the nutation interferogram can be measured "stroboscopically" between the pulses. The maximum time saving factor that can be obtained as compared to the conventional nutation experiment is of the order of the number of pulses used in a pulse train. The method has been successfully applied for determination of the asymmetry parameter for one of the two 3 5 Cl sites in polycrystalline 2,4,6-trichloro-1,3,5-triazine (cyanuric chloride).


2019 ◽  
Vol 84 ◽  
pp. 02008
Author(s):  
Lubomir Marciniak ◽  
Mateusz Piątek

Detection of high resistance earth faults in medium voltage networks is an important problem due to ineffectiveness of traditional earth fault protections. Such short circuits can be detected by the criterion of a reactive power of higher harmonics for zero sequence current and voltage. The main problem is determination of the power setting value in the protection, which depends on the asymmetry of phase-to-earth capacitances and higher harmonics in supply voltages, which are generated by non-linear loads. The intensive tests of the asymmetry of the zero sequence currents and voltages for harmonics and their reactive power have been carried out in 15 kV compensated network as a function of all relevant parameters, i.e.: maximum capacitance deviation of the network and protected line, percentage content of harmonics in supply voltages, capacitive current of the network and the line. It has been shown that third harmonics of the zero sequence voltage and current are the best suited for practical use, since the asymmetry reactive power of these components is the smallest among the considered harmonics and the protection sensitivity will be the highest.


2004 ◽  
Vol 95 (8) ◽  
pp. 3984-3987 ◽  
Author(s):  
L. Largeau ◽  
G. Patriarche ◽  
F. Glas ◽  
E. Le Bourhis

2017 ◽  
Vol 32 (11) ◽  
pp. 1750060 ◽  
Author(s):  
Ahmed Rashed ◽  
Alakabha Datta

Crucial developments in neutrino physics would be the determination of the mass hierarchy (MH) and measurement of the CP phase in the leptonic sector. The patterns of the transition probabilities [Formula: see text] and [Formula: see text] are sensitive to these oscillation parameters. An asymmetry parameter can be defined as the difference of these two probabilities normalized to their sum. The profile of the asymmetry parameter gives a clear signal of the mass ordering as it is found to be positive for inverted hierarchy and negative for normal hierarchy. The asymmetry parameter is also sensitive to the CP phase. We consider the effects of nonstandard neutrino interactions (NSI) on the determination of the mass hierarchy. Since we assume the largest new physics effects involve the [Formula: see text] sector only, we ignore NSI in production and study the NSI effects in detection as well as along propagation. We find that the NSI effects can significantly modify the prediction of the asymmetry parameter though the MH can still be resolved.


1998 ◽  
Vol 15 (2) ◽  
pp. 215-225 ◽  
Author(s):  
N. Sinjavsky ◽  
M. Ostafin ◽  
M. Maékowiak

2015 ◽  
Vol 7 (3) ◽  
Author(s):  
Shaoping Bai ◽  
Jorge Angeles

This paper focuses on the problem of synthesis of spatial four-bar linkages of the RCCC type for rigid-body guidance with four given poses, R denoting a revolute, C a cylindrical kinematic pair. While synthesis equations for CC and RC dyads are available in the literature, the synthesis of spatial RCCC four-bar linkages requires special attention, due to its asymmetric topology. We revisit the problem to cope robustly with the asymmetry, namely, the approximate nature of the RC dyad and the infinity of exact solutions of the CC dyad for the number of given poses. Our approach includes a robust formulation of the synthesis of CC dyads, for the determination of axis-congruences. Moreover, we formulate a uniform synthesis equation, which enables us to treat both RC and CC dyads, with properly selected constraints for both cases. Two design examples are included.


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