1H -14N Nuclear Quadrupole Double Resonance with Multiple Frequency Sweeps

1994 ◽  
Vol 49 (1-2) ◽  
pp. 31-34 ◽  
Author(s):  
J. Seliger ◽  
V. Žagar ◽  
R. Blinc
Keyword(s):  
Magnetic Field ◽  
Double Resonance ◽  
Experimental Results ◽  
New Technique ◽  
Multiple Frequency ◽  
Resonance Technique ◽  
Highly Sensitive ◽  
Field Cycling ◽  
Nuclear Quadrupole ◽  
Frequency Sweeps

Abstract A new highly sensitive 1H -14N nuclear quadrupole double resonance technique is presented which is based on magnetic field cycling and on the application of multiple frequency sweeps of an r.f. magnetic field. The sensitivity and the resolution o f the new technique are estimated. Some experimental results obtained by the new technique are presented.

A New Nuclear-Quadrupole Double-Resonance Technique based on Solid Effect

1997 ◽  
Vol 52 (4) ◽  
pp. 337-342 ◽  
Author(s):  
J. Seliger ◽  
V. Žagar
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Double Resonance ◽  
Spin Lattice Relaxation ◽  
New Technique ◽  
Simultaneous Application ◽  
Resonance Technique ◽  
Solid Effect ◽  
Nuclear Quadrupole ◽  
Rf Magnetic Field

Abstract A new nuclear-quadrupole double-resonance technique is described. It has a higher sensitivity and a higher resolution than the conventional nuclear-quadrupole double-resonance technique based on solid effect. The new technique involves magnetic field cycling between a high and a low static magnetic field and simultaneous application of two rf magnetic fields when the sample is in the low static magnetic field. A strong rf magnetic field induces "forbidden" simultaneous transitions in a magnetic (usually 1H) and in a quadrupole spin system and thus couples the two spin systems. A weak rf magnetic field induces transitions between the energy levels of the quadrupole nuclei and simulates a fast spin-lattice relaxation of the quadrupole nuclei when its frequency matches an NQR frequency. The sensitivity and resolution of the new technique are discussed and test measurements in tris-sarcosine calcium chloride are presented.

A Low-Temperature High-Sensitivity Field-Cycling Spectrometer for Quadrupole Double Resonance Spectroscopy

1990 ◽  
Vol 45 (3-4) ◽  
pp. 595-598 ◽  
Author(s):  
M. M. P. Khurshid ◽  
F. Zhenye ◽  
J.A.S. Smith
Keyword(s):  
Variable Temperature ◽  
Double Resonance ◽  
High Sensitivity ◽  
Resonance Spectroscopy ◽  
Quadrupole Resonance ◽  
Field Cycling ◽  
Double Resonance Spectroscopy ◽  
Nuclear Quadrupole ◽  
The Magnetic Field ◽  
Sensitivity Field

Abstract This paper discusses the design of a variable-temperature high-sensitivity field cycling spectrometer for nuclear magnetic resonance and nuclear quadrupole double resonance experiments. The instrument is capable of detecting N-14 quadrupole resonance signals from samples as small as 0.1 g down to temperatures of 150 K. The magnetic field cycling is performed by mechanical transfer of the sample using a pair of switchable electromagnetic solenoids, in times of about 0.2 s.

1H - 17O Nuclear Quadrupole Double Resonance in DL-Proline

1990 ◽  
Vol 45 (5) ◽  
pp. 733-735 ◽  
Author(s):  
J. Seliger ◽  
V. Žagar ◽  
R. Blinc ◽  
P. K. Kadaba ◽  
D. Fiat
Keyword(s):  
Nuclear Quadrupole Resonance ◽  
Double Resonance ◽  
Unit Cell ◽  
The Other ◽  
Resonance Technique ◽  
Quadrupole Resonance ◽  
Nuclear Quadrupole

Abstract 17O nuclear quadrupole resonance spectra have been measured in an 17O enriched polycristalline sample of DL-proline with the help of 1H - 17O nuclear quadrupole double resonance technique. The results show the presence of eight chemically inequivalent oxygen sites corresponding to four inequivalent proline molecules in the unit cell. The oxygen sites may be grouped into two sets of four sites. One set with the short proton-oxygen distances belongs to the C - O • • • H groups whereas the other with the long proton-oxygen distances to the C = O groups

A Technique for the Laboratory Determination of Recirculation in Single Needle Dialysis

1993 ◽  
Vol 16 (2) ◽  
pp. 63-70 ◽  
Author(s):  
N.A. Hoenich ◽  
P.T. Smirthwaite ◽  
C. Woffindin ◽  
P. Lancaster ◽  
T.H. Frost ◽  
...  
Keyword(s):  
Experimental Data ◽  
Flow Rate ◽  
Experimental Results ◽  
New Technique ◽  
Treatment Efficiency ◽  
Single Lumen ◽  
Theoretical Predictions ◽  
Lumen Catheter ◽  
A New Technique

Recirculation is an important factor in single needle dialysis and, if high, can compromise treatment efficiency. To provide information regarding recirculation characteristics of access devices used in single needle dialysis, we have developed a new technique to characterise recirculation and have used this to measure the recirculation of a Terumo 15G fistula needle and a VasCath SC2300 single lumen catheter. The experimentally obtained results agreed well with those established clinically (8.5 ± 2.4% and 18.4 ± 3.4%). The experimental results have also demonstrated a dependence on access type, pump speeds and fistula flow rate. A comparison of experimental data with theoretical predictions showed that the latter exceeded those measured with the largest contribution being due to the experimental fistula.

A Contribution to the Microwave Double Resonance Technique and Measurements of Collision Induced Transitions

1979 ◽  
Vol 34 (5) ◽  
pp. 571-574 ◽  
Author(s):  
H. Dreizier ◽  
W. Schrepp ◽  
R. Schwarz
Keyword(s):  
Millimeter Wave ◽  
Double Resonance ◽  
Absorption Cell ◽  
Resonance Technique ◽  
Wave Region

Abstract A construction for a versatile absorption cell is presented, which may be used for a large variety of double resonance experiments in the radiofrequency, microwave and millimeter wave region. Some measurements of collision induced transitions are reported.

Sign in / Sign up

Export Citation Format

Share Document