Log in

Relevant bibliographies by topics / NQR Spectrometer / Journal articles

To see the other types of publications on this topic, follow the link: NQR Spectrometer.

Journal articles on the topic 'NQR Spectrometer'

Author: Grafiati

Published: 12 October 2024

Last updated: 31 July 2025

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'NQR Spectrometer.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Preeti, Hemnani, K. Rajarajan A., Joshi Gopal, and V. G. Ravindranath S. "Design of probe for NQR/NMR detection." International Journal of Electrical and Computer Engineering (IJECE) 10, no. 4 (2020): 3468–75. https://doi.org/10.11591/ijece.v10i4.pp3468-3475.

Full text

Abstract:

Nuclear Magnetic Resonance (NMR) is a RF technique that is able to detect any compound by sensing the excited resonance signals from atomic nuclei having non-zero spin. NQR is similar to NMR but the only difference is NMR needs a DC magnetic field and due to this its application in the field is limited. A FPGA based NQR spectrometer is designed using a single FPGA chip to perform the digital tasks required for NQR spectrometer. Design of Probe for NMR/NQR spectrometer is researched. Parallel tuned and series tuned Probes are discussed and simulated.14N NQR from

APA, Harvard, Vancouver, ISO, and other styles

2

Hemnani, Preeti, A. K. Rajarajan, Gopal Joshi, and S. V. G. Ravindranath. "Design of probe for NQR/NMR detection." International Journal of Electrical and Computer Engineering (IJECE) 10, no. 4 (2020): 3468. http://dx.doi.org/10.11591/ijece.v10i4.pp3468-3475.

Full text

Abstract:

Nuclear Magnetic Resonance (NMR) is a RF technique that is able to detect any compound by sensing the excited resonance signals from atomic nuclei having non-zero spin. NQR is similar to NMR but the only difference is NMR needs a DC magnetic field and due to this its application in the field is limited. A FPGA based NQR spectrometer is designed using a single FPGA chip to perform the digital tasks required for NQR spectrometer. Design of Probe for NMR/NQR spectrometer is researched. Parallel tuned and series tuned Probes are discussed and simulated.14N NQR from NaNO2 is observed from spectrome

APA, Harvard, Vancouver, ISO, and other styles

3

Preeti, Hemnani, K. Rajarajan A., Joshi Gopal, and V. G. Ravindranath S. "The Building of Pulsed NQR/NMR Spectrometer." International Journal of Electrical and Computer Engineering (IJECE) 8, no. 3 (2018): 1442–50. https://doi.org/10.11591/ijece.v8i3.pp1442-1450.

Full text

Abstract:

NQR spectrometer designed is composed of four modules; Transmitter, Probe, Receiver and computer controlled (FPGA & Software) module containing frequency synthesizer, synchronous demodulator, pulse programmer and display. The function of the Transmitter module is to amplify the RF pulse sequence to about 200 W power level into the probe (50 Ohm) which is a parallel resonance circuit with a tapped capacitor. The probe excites the nucleus and picks-up the signal emitted from the nuclei. The nuclear signal at the same frequency as the excitation, which is typically in the range of a few micro

APA, Harvard, Vancouver, ISO, and other styles

4

Bielecki, A., D. B. Zax, K. W. Zilm, and A. Pines. "Zero‐field NMR and NQR spectrometer." Review of Scientific Instruments 57, no. 3 (1986): 393–403. http://dx.doi.org/10.1063/1.1138898.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Hemnani, Preeti, A. K. Rajarajan, Gopal Joshi, and S. V. G. Ravindranath. "The Building of Pulsed NQR/NMR Spectrometer." International Journal of Electrical and Computer Engineering (IJECE) 8, no. 3 (2018): 1442. http://dx.doi.org/10.11591/ijece.v8i3.pp1442-1450.

Full text

Abstract:

<p>NQR spectrometer designed is composed of four modules; Transmitter, Probe, Receiver and computer controlled (FPGA &amp; Software) module containing frequency synthesizer, synchronous demodulator, pulse programmer and display. The function of the Transmitter module is to amplify the RF pulse sequence to about 200 W power level into the probe (50 Ohm) which is a parallel resonance circuit with a tapped capacitor. The probe excites the nucleus and picks-up the signal emitted from the nuclei. The nuclear signal at the same frequency as the excitation, which is typically in the range o

APA, Harvard, Vancouver, ISO, and other styles

6

Blanz, M., T. J. Rayner, and J. A. S. Smith. "A fast field-cycling NMR/NQR spectrometer." Measurement Science and Technology 4, no. 1 (1993): 48–59. http://dx.doi.org/10.1088/0957-0233/4/1/009.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Mano, Koichi, and Masao Hashimoto. "Computer Enhanced SRO NQR-Spectrometer." Zeitschrift für Naturforschung A 41, no. 1-2 (1986): 445–48. http://dx.doi.org/10.1515/zna-1986-1-287.

Full text

Abstract:

An automatic computer supported SRO NQR spectrometer system was constructed for the measurement of time dependent NQR signal intensities. The system has several functions: fast scanning (500 kH z/25 s), averaging, smoothing, automatic noise level estimation, automatic peak detection, etc. The process of the ß → α phase transition of p-dichlorobenzene is illustrated by the 3-dimensional spectrum .

APA, Harvard, Vancouver, ISO, and other styles

8

Schiano, J. L., and M. D. Ginsberg. "A Pulsed Spectrometer Designed for Feedback NQR." Zeitschrift für Naturforschung A 55, no. 1-2 (2000): 61–66. http://dx.doi.org/10.1515/zna-2000-1-212.

Full text

Abstract:

A pulsed NQR spectrometer specifically designed to facilitate real-time tuning of pulse sequence parameters is described. A modular approach based on the interconnection of several rack-mounted blocks provides easy access to all spectrometer signals and simplifies the task of modifying the spectrometer design. We also present experimental data that demonstrates the ability of the spectrometer to increase the signal to noise ratio of NQR measurements by automatically adjusting the pulse width in the strong off-resonant comb pulse sequence.

APA, Harvard, Vancouver, ISO, and other styles

9

Hemnani, Preeti, A. K. Rajarajan, Gopal joshi, and S. V. G. Ravindranath. "FPGA Based RF Pulse Generator for NQR/NMR Spectrometer." Procedia Computer Science 93 (2016): 161–68. http://dx.doi.org/10.1016/j.procs.2016.07.196.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Khusnutdinov, R. R., G. V. Mozzhukhin, N. R. Khusnutdinova, and B. M. Salakhutdinov. "High-Q litz wire NQR sensor for medical applications." Power engineering: research, equipment, technology 25, no. 3 (2023): 3–11. http://dx.doi.org/10.30724/1998-9903-2023-25-3-3-11.

Full text

Abstract:

RELEVANCE. The design and development of radio frequency (RF) coil sensors is an important engineering and, at the same time, fundamental task for those radio spectroscopic instruments that require an increase in sensitivity, measured as a signal-to-noise ratio (SNR). Radio spectroscopy of nuclear quadrupole resonance (NQR), especially in nitrogen compounds, in which the resonant frequency is very low and ranges from a few megahertz or lower to hundreds of kilohertz, requires the use of special solutions to increase the sensitivity. PURPOSE. Theoretical substantiation and search for a technica

APA, Harvard, Vancouver, ISO, and other styles

11

Zhenye, Feng, Edwin A. C. Lücken, and Jacques Diolot. "A Computer-controlled, Fully Automatic NMR/NQR Double Resonance Spectrometer." Zeitschrift für Naturforschung A 47, no. 1-2 (1992): 395–400. http://dx.doi.org/10.1515/zna-1992-1-266.

Full text

Abstract:

AbstractA completely automatic computer-controlled NMR/NQR double resonance spectrometer is described. It features automatic tuning of the low, variable frequency power amplifier, thus permitting untended use over long periods, with high sensitivity and signal reproducibility. The sample is transferred between the low-frequency, zero-field region and the high-field region using compressed air and the possibility of switching on a field of several tens of gauss during the transfer of the sample is also included

APA, Harvard, Vancouver, ISO, and other styles

12

Zikumaru, Yushi. "NQR Spectrometer with a Two Integrated Circuits Radio Frequency Head." Zeitschrift für Naturforschung A 45, no. 3-4 (1990): 591–94. http://dx.doi.org/10.1515/zna-1990-3-467.

Full text

Abstract:

Abstract An NQR spectrometer has been constructed using two linear integrated circuits in its oscillator-detector. This is very simple and compact and works in range 3-65 MHz. The radio frequency voltage can be varied from 10 mVp-p to 15 V p-p by changing the supply-voltage of an integrated circuit μA 733. The utility of the spectrometer is demonstrated by recording 35Cl NQR spectra in p-C6H4Cl2 , NaClO3 , and KClO3 .

APA, Harvard, Vancouver, ISO, and other styles

13

Lee, Donghoon, S. J. Gravina, and P. J. Bray. "NQR Studies of Atomic Arrangements and Chemical Bonding in Glasses." Zeitschrift für Naturforschung A 45, no. 3-4 (1990): 268–72. http://dx.doi.org/10.1515/zna-1990-3-412.

Full text

Abstract:

Abstract A very high sensitivity continuous wave NQR spectrometer was developed to detect pure NQR transitions at low frequencies (down to 200 kHz). A signal-to-noise ratio of more than 100 to 1 has been achieved at about 1.36 MHz for crystalline B 2 0 3 . Two large n B responses have been found in vitreous B 2 0 3 (NMR detected only one site) with linewidths of less than 30 kHz. 27 A1 NQR spectra were obtained for OC-A1203 (Corundum), the mineral andalusite (a form of A1203 • Si0 2), and a glass having the composition of anorthite (CaO • A1203 • 2Si0 2).

APA, Harvard, Vancouver, ISO, and other styles

14

Osokin, D. Ya, and R. R. Khusnutdinov. "A two-frequency coherent pulse NQR spectrometer." Instruments and Experimental Techniques 52, no. 1 (2009): 85–89. http://dx.doi.org/10.1134/s0020441209010138.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Beguš, Samo, Vojko Jazbinšek, Janez Pirnat, and Zvonko Trontelj. "A miniaturized NQR spectrometer for a multi-channel NQR-based detection device." Journal of Magnetic Resonance 247 (October 2014): 22–30. http://dx.doi.org/10.1016/j.jmr.2014.08.002.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Pirnat, J., J. Lužnik, and Z. Trontelj. "Iodine NQR and Phase Transitions in [N(CH3)4]2 ZnI4." Zeitschrift für Naturforschung A 45, no. 3-4 (1990): 349–52. http://dx.doi.org/10.1515/zna-1990-3-423.

Full text

Abstract:

Abstract Using a superregenerative NQR spectrometer, the temperature dependence of 127I NQR spectra in [N(CH3)4]2ZnI4 was measured between 167 and 335 K. The measurements confirm two known structural phase transitions at 219 and 257.5 K. The correspondence between the distinct regions of iodine NQR spectra and the crystal structure is discussed. The relation of [N(CH3)4]2ZnI4 to the incommensurate family with the general formula X2YZ4 and the high temperature (paraphase) crystal space group D162h (Pmcn) is studied.

APA, Harvard, Vancouver, ISO, and other styles

17

Choi, K., and I. Yu. "Inductive detection of piezoelectric resonance by using a pulse NMR/NQR spectrometer." Review of Scientific Instruments 60, no. 10 (1989): 3249–52. http://dx.doi.org/10.1063/1.1140560.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Reddy, Narsimha, Arun Bhavsar, and P. T. Narasimhan. "Microprocessor-Controlled Pulsed NQR Spectrometer for Automatic Acquisition of Zeeman Perturbed Nuclear Quadrupole Spin Echo Envelope Modulations (ZSEEM )." Zeitschrift für Naturforschung A 41, no. 1-2 (1986): 449–52. http://dx.doi.org/10.1515/zna-1986-1-288.

Full text

Abstract:

A simple microprocessor-controlled pulsed NQR spectrometer system has been developed with the capability to acquire Zeeman perturbed spin echo envelope modulations (ZSEEM). The CPU of the system is based on the Intel Corporation 8085 A microprocessor. The performance of the spectrometer is illustrated with the presentation of ZSEEM spectra of NaClO3 and KClO3.

APA, Harvard, Vancouver, ISO, and other styles

19

Hotra, Oleksandra, and Andriy Samila. "A Low-Cost Digital Pulsed Coherent Spectrometer for Investigation of NQR in Layered Semiconductor GaSe and InSe Crystals." Electronics 9, no. 12 (2020): 1996. http://dx.doi.org/10.3390/electronics9121996.

Full text

Abstract:

A low-cost digital pulsed nuclear quadrupole resonance (NQR) radio-spectrometer is proposed, all main modules of digital processing and synthesis of which on the field-programmable gate array (FPGA) are implemented. The input sensitivity of the device is of the order of 3 μV to 5 μV which allows conducting NQR studies in samples of relatively small dimensions. The application of the developed methods of NQR pulsed radio spectroscopy made it possible to increase spectral resolution, improve spectral shape and significantly reduce the time of research. In the case of studying InSe and GaSe cryst

APA, Harvard, Vancouver, ISO, and other styles

20

Samila, Andriy, Alexander Khandozhko, Ivan Hryhorchak, Leonid Politans’kyy, and Taras Kazemirskiy. "A CONTROL UNIT FOR A PULSED NQR-FFT SPECTROMETER." Informatics, Control, Measurement in Economy and Environment Protection 5, no. 4 (2015): 55–58. http://dx.doi.org/10.5604/20830157.1176577.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Хандожко, Александр Григорьевич, Виктор Александрович Хандожко, and Андрей Петрович Самила. "A pulse coherent nqr spectrometer with effective transient suppression." Eastern-European Journal of Enterprise Technologies 6, no. 12(66) (2013): 21. http://dx.doi.org/10.15587/1729-4061.2013.19700.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Monea, Cristian, Gabriel V. Iana, Silviu Ionita, et al. "An optimized NQR spectrometer for detection of prohibited substances." Measurement 151 (February 2020): 107158. http://dx.doi.org/10.1016/j.measurement.2019.107158.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Trontelj, Zvonko, Janez Pirnat, Vojko Jazbinšek, et al. "Nuclear Quadrupole Resonance (NQR)—A Useful Spectroscopic Tool in Pharmacy for the Study of Polymorphism." Crystals 10, no. 6 (2020): 450. http://dx.doi.org/10.3390/cryst10060450.

Full text

Abstract:

Nuclear Quadrupole Resonance (NQR) spectroscopy has been known for 70 years. It is suitable for the study of measured (poly)crystalline chemical compounds containing quadrupole nuclei (nuclei with spin I ≥ 1) where the characteristic NQR frequencies represent the fingerprints of these compounds. In several cases, 14N NQR can distinguish between the polymorphic crystalline phases of active pharmaceutical ingredients (APIs). In order to further stimulate 14N NQR studies, we review here several results of API polymorphism studies obtained in Ljubljana laboratories: (a) In sulfanilamide, a clear d

APA, Harvard, Vancouver, ISO, and other styles

24

Ostafin, Michał, Mariusz Maćkowiak, and Marek Bojarski. "Automatically Tuned Probe Head System for Pulsed NQR Spectroscopy in Extreme Thermodynamic Conditions." Zeitschrift für Naturforschung A 49, no. 1-2 (1994): 42–46. http://dx.doi.org/10.1515/zna-1994-1-210.

Full text

Abstract:

Abstract A complete N Q R probe-head system operating in the frequency ranges 0.5 -150 and 150- 300 MHz is described. The head is particularly suited for NQR experiments carried out at a remote location, for example in a low-temperature cryostat or high-pressure chamber. Moreover, the head system includes a microprocessor-controller for automated tuning of the probe to the operating frequency of the associated NQR spectrometer. The controller can be easily interfaced to a PC via standard serial port.

APA, Harvard, Vancouver, ISO, and other styles

25

Honda, H., A. Sasane, K. Miyagi, A. Ishikawa, and Y. Mori. "81Br NQR for Uncoordinated Br ions in trans-[CoBr2(en)2][H5O2]Br2 and trans-[CoBr2(en)2] [D5O2]Br2." Zeitschrift für Naturforschung A 49, no. 1-2 (1994): 209–12. http://dx.doi.org/10.1515/zna-1994-1-232.

Full text

Abstract:

AbstractThe temperature dependence of the 81Br NQR frequencies (vD) for uncoordinated Br- ions in trans-[CoBr2(en)2] [D5O2]Br2(D) has been determined by a continuous-wave spectrometer. vD amounted to 16.200 MHz at 273 K. This is lower by 418 kHz than the 81Br NQR frequency (vH) for trans-[CoBr2 (en2] [H5O2 ]Br2 (H). The frequency difference (Δv = vH -vD) remained almost constant in the temperature range studied. A shortening of the O-H bond length caused by deuteration could explain the magnitude and the sign of Av on the basis of a point charge model calculation. The compounds D and H yielded

APA, Harvard, Vancouver, ISO, and other styles

26

Scharfetter, Hermann, Markus Bödenler, and Dominik Narnhofer. "A cryostatic, fast scanning, wideband NQR spectrometer for the VHF range." Journal of Magnetic Resonance 286 (January 2018): 148–57. http://dx.doi.org/10.1016/j.jmr.2017.12.004.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Sullivan, E. P. A. "Estimating relaxation times with a very simple ratemeter-type NQR spectrometer." Journal of Molecular Structure 319 (March 1994): 285–88. http://dx.doi.org/10.1016/0022-2860(93)07925-m.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Maćkowiak, Mariusz, and Piotr Kątowski. "Enhanced Information Recovery in 2D On-and Off-Resonance Nutation NQR using the Maximum Entropy Method." Zeitschrift für Naturforschung A 51, no. 5-6 (1996): 337–47. http://dx.doi.org/10.1515/zna-1996-5-605.

Full text

Abstract:

Abstract Two-dimensional zero-field nutation NQR spectroscopy has been used to determine the full quadrupolar tensor of spin - 3/2 nuclei in serveral molecular crystals containing the 3 5 Cl and 7 5 As nuclei. The problems of reconstructing 2D-nutation NQR spectra using conventional methods and the advantages of using implementation of the maximum entropy method (MEM) are analyzed. It is shown that the replacement of conventional Fourier transform by an alternative data processing by MEM in 2D NQR spectroscopy leads to sensitivity improvement, reduction of instrumental artefacts and truncation

APA, Harvard, Vancouver, ISO, and other styles

29

Garcia, Maria L. S., and Edwin A. C. Lucken. "(CH3)3CCOOSbCl4: Structure Determination by Zeeman Perturbed NQR." Zeitschrift für Naturforschung A 41, no. 1-2 (1986): 129–33. http://dx.doi.org/10.1515/zna-1986-1-219.

Full text

Abstract:

A single crystal of tetrachloro(0,0-pivaloylato)antimony(V) has been studied at 77 K, byZeeman perturbed 35Cl NQR, using a FT-NQR pulsed spectrometer. The four lines at zero-field, ν1 = 27.6468, ν2= 27.3070, ν3= 25.7341 and ν4= 25.3438 MHz yield eight EFG tensors in themagnetic field, related by a twofold symmetry element in the crystal. The correspondingasymmetry parameters are η1, = 0.134, η2 = 0.13, η3= 0.07, and η4 = 0.09. The molecular structurededuced from the relative orientations of the principal Z-axes of the EFG tensors confirms that thehigher quadrupole coupling constants are associ

APA, Harvard, Vancouver, ISO, and other styles

30

Rudakov, T. N., V. V. Fedotov, A. V. Belyakov, and V. T. Mikhal’tsevich. "Suppression of transient processes in the oscillatory circuit of the NQR spectrometer." Instruments and Experimental Techniques 43, no. 1 (2000): 78–81. http://dx.doi.org/10.1007/bf02759003.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Samila, A. P., and А. П. Саміла. "Hardware and software implementation of data acquisition system for pulsed NQR spectrometer." Технология и конструирование в электронной аппаратуре, no. 1-2 (April 2017): 16–22. http://dx.doi.org/10.15222/tkea2017.1-2.16.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Clarke, John. "Low Frequency Nuclear Quadrupole Resonance with SQUID Amplifiers." Zeitschrift für Naturforschung A 49, no. 1-2 (1994): 5–13. http://dx.doi.org/10.1515/zna-1994-1-204.

Full text

Abstract:

Abstract The dc SQUID (Superconducting QUantum Interference Device) can be configured as an amplifier of spin-echos with a noise temperature of approximately 10 mK (f/1 M Hz) at an operating temperature of 1.5 K. A Fourier transform spectrometer based on a SQUID with a superconducting input circuit and operated in a flux-locked loop is used to obtain nuclear quadrupole resonance (NQR) spectra in a broadband m ode over the bandwith 0 -1 M Hz. Spin-echo spectra of 14N in NH4ClO4 reveal sharp NQR resonances, obtained simultaneously, at 17.4, 38.8 and 56.2 kHz. At 1.5 K, the measured longitudinal

APA, Harvard, Vancouver, ISO, and other styles

33

Sikorsky, Tomas, Andrzej Pelczar, Stephan Schneider, and Thorsten Schumm. "Integrating superregenerative principles in a compact, power-efficient NMR/NQR spectrometer: A novel approach with pulsed excitation." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1062 (May 2024): 169239. http://dx.doi.org/10.1016/j.nima.2024.169239.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Manallah, B. "Delayed Double Resonance Between Quadrupolar Levels: Observation of a Nuclear Spin Emission Signal in s-Triazine." Zeitschrift für Naturforschung A 41, no. 1-2 (1986): 396–98. http://dx.doi.org/10.1515/zna-1986-1-276.

Full text

Abstract:

A delayed double resonance experiment was carried out using a Robinson-type continuous wave spectrometer. The sample chosen was s-triazine at liquid helium temperature, where the relaxation times are of the order of ten hours. Line pairings between the two Nitrogen-14 NQR sites were confirmed. Emission signals from ν- transitions were observed after successively saturating first the ν- line and then the ν+ line. The results are understood in terms of a simple model of spin population dynamics.

APA, Harvard, Vancouver, ISO, and other styles

35

Ganal, P., T. Butz, A. Lerf, M. Naito, and H. Nishihara. "The 181Ta Nuclear Quadrupole Interaction in the Charge Density Wave Phases of 1T-TaS2." Zeitschrift für Naturforschung A 45, no. 3-4 (1990): 439–44. http://dx.doi.org/10.1515/zna-1990-3-439.

Full text

Abstract:

Abstract With a high resolution time differential perturbed angular correlation spectrometer we investigated the nuclear quadrupole interaction of Ta in 1T-TaS2 . The results obtained for the commensurate charge density wave phase lead to a revised assignment of the previously observed 181Ta NQR resonances. Differences in the intracluster architecture of the 13-atom Star of David cluster between 1T-TaS2 and 1T-TaSe2 could be responsible for the metal to semiconductor transition which occurs in lT-TaS2 but not in lT-TaSe2 .

APA, Harvard, Vancouver, ISO, and other styles

36

Trepanier, R. J., and M. A. Whitehead. "Line Width Narrowing with 14N Nuclear Quadrupole Resonance Lines at 296 K and 77 K Using a High Powered Pulsed Spectrometer." Zeitschrift für Naturforschung A 41, no. 1-2 (1986): 386–91. http://dx.doi.org/10.1515/zna-1986-1-274.

Full text

Abstract:

The dependence of the NQR line width on the RF pulse intensity and period using a continuous steady state pulse train for polycrystalline 14N compounds shows a dependence on the asymmetry parameter η, the temperature, and the crystal structure.

APA, Harvard, Vancouver, ISO, and other styles

37

Samila, A., V. Khandozhko, and L. Politansky. "Energy efficiency increase of NQR spectrometer transmitter at pulse resonance excitation with noise signals." Solid State Nuclear Magnetic Resonance 87 (October 2017): 10–17. http://dx.doi.org/10.1016/j.ssnmr.2017.06.001.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Rozorinov, Heorhii, Olena Nenia, Nataliia Bereznenko, and Petro Mamotenko. "Simulation of Radio Pulse Generator of NQR Spectrometer for the Detection of Explosives and Narcotic Substances." Modern Special Technics 61, no. 2 (2020): 151–61. http://dx.doi.org/10.36486/mst2411-3816.2020.2(61).15.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Horiuchi, Keizo, Ryuichi Ikeda, and Daiyu Nakamura. "Phase transition and anionic motion in solid [(CH3)2NH2]2SnCl6as studied by the temperature dependence of35Cl NQR frequencies and chlorine nuclear relaxation times determined with a pulsed NQR spectrometer." Berichte der Bunsengesellschaft für physikalische Chemie 91, no. 12 (1987): 1351–59. http://dx.doi.org/10.1002/bbpc.19870911209.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Harbison, Gerard S., and Andris Slokenbergs. "Two-dimensional Nutation Echo Nuclear Quadrupole Resonance Spectroscopy." Zeitschrift für Naturforschung A 45, no. 3-4 (1990): 575–80. http://dx.doi.org/10.1515/zna-1990-3-464.

Full text

Abstract:

Abstract We discuss two new two-dimensional nuclear quadrupole resonance experiments, both based on the principle of nutation spectroscopy, which can be used to determine the asymmetry parameter, and thus the full quadrupolar tensor, of spin-3/2 nuclei at zero applied magnetic field. The first experiment is a simple nutation pulse sequence in which the first time period (t1) is the duration of the radiofrequency exciting pulse; and the second (t2) is the normal free-precession of a quadrupolar nucleus at zero-field. After double Fourier-transformation, the result is a 2 D spectrum in which the

APA, Harvard, Vancouver, ISO, and other styles

41

Jonsen, Paul. "5036279 Portable NMR and NQR spectrometers." Magnetic Resonance Imaging 11, no. 2 (1993): V. http://dx.doi.org/10.1016/0730-725x(93)90057-k.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Shen, Zefang, Haylee D'Agui, Lewis Walden, et al. "Miniaturised visible and near-infrared spectrometers for assessing soil health indicators in mine site rehabilitation." SOIL 8, no. 2 (2022): 467–86. http://dx.doi.org/10.5194/soil-8-467-2022.

Full text

Abstract:

Abstract. Mining can cause severe disturbances to the soil, which underpins the viability of terrestrial ecosystems. Post-mining rehabilitation relies on measuring soil properties that are critical indicators of soil health. Soil visible–near-infrared (vis–NIR) spectroscopy is rapid, accurate, and cost-effective for estimating a range of soil properties. Recent advances in infrared detectors and microelectromechanical systems (MEMSs) have produced miniaturised, relatively inexpensive spectrometers. Here, we evaluate the spectra from four miniaturised visible and NIR spectrometers, some combina

APA, Harvard, Vancouver, ISO, and other styles

43

Jobert, Gabriel, and Xavier Brenière. "Mid-Infrared Spectrometer for Black Plastics Sorting Using a Broadband Uncooled Micro-Bolometer Array." Spectroscopy Journal 3, no. 2 (2025): 13. https://doi.org/10.3390/spectroscj3020013.

Full text

Abstract:

We report the design, implementation and test of a Mid-Infrared spectrometer proof-of-concept that utilizes an uncooled micro-bolometer array, sensitive in the 3–14 µm spectral range, integrated in a conventional optical dispersive spectrometry setup. Such a spectrometer enables instantaneous measurements across this broad spectral range, comparable to that of a FTIR but with a more compact design and without moving parts. This makes it ideal for integration into portable, battery-powered devices such as handheld scanners. The Mid-IR range offers significant advantages over NIR-SWIR spectromet

APA, Harvard, Vancouver, ISO, and other styles

44

Zhu, Chenxi, Xiaping Fu, Jianyi Zhang, Kai Qin, and Chuanyu Wu. "Review of portable near infrared spectrometers: Current status and new techniques." Journal of Near Infrared Spectroscopy 30, no. 2 (2022): 51–66. http://dx.doi.org/10.1177/09670335211030617.

Full text

Abstract:

Near infrared (NIR) spectroscopy is a non-destructive detection technology involving NIR spectral data acquisition and chemometric treatment. The use of an NIR spectrometer is evidently crucial in this regard; however, traditional benchtop NIR spectrometers considerably limit usage scenarios. Accordingly, the miniaturization of spectrometers with high level performance has become a research trend. Various commercial products have been developed, and new techniques have been applied to produce more portable NIR spectrometers. This paper reviews the main types of commercial portable NIR spectrom

APA, Harvard, Vancouver, ISO, and other styles

45

Rukundo, Isaac R., Mary-Grace C. Danao, Robert B. Mitchell, Steven D. Masterson, and Curtis L. Weller. "Comparing the Use of Handheld and Benchtop NIR Spectrometers in Predicting Nutritional Value of Forage." Applied Engineering in Agriculture 37, no. 1 (2021): 171–81. http://dx.doi.org/10.13031/aea.14157.

Full text

Abstract:

HighlightsA transportable spectrometer performed similarly to benchtop spectrometers to predict forage quality.Absorption bands in the second and third overtone regions were used to predict forage quality with ample accuracy.A low-cost handheld spectrometer was useful for routine screening of forage for nitrogen content. Abstract. Assessing the nutritional composition of animal feed and forage materials is important to achieve high animal productivity and wellness. Precision nutrition programs that use NIR technology can determine the nutritional composition of feed and forage quickly and simp

APA, Harvard, Vancouver, ISO, and other styles

46

Wikus, Patrick, Wolfgang Frantz, Rainer Kümmerle, and Patrik Vonlanthen. "Commercial gigahertz-class NMR magnets." Superconductor Science and Technology 35, no. 3 (2022): 033001. http://dx.doi.org/10.1088/1361-6668/ac4951.

Full text

Abstract:

Abstract Nuclear magnetic resonance (NMR) spectroscopy is a wide-spread analytical technique which is used in a large range of different fields, such as quality control, food analysis, material science and structural biology. In the widest sense, NMR is an analytical technique to determine the structure of molecules. At the time of writing this manuscript, commercial NMR spectrometers with a proton resonance frequency ⩾900 MHz are only available from Bruker. In 2019, Bruker installed the first 1.1 GHz (25.8 T) NMR spectrometer at the St. Jude Children Research Hospital in Memphis, Tennessee, f

APA, Harvard, Vancouver, ISO, and other styles

47

Tu, Zhiyang (Stan), Joseph Irudayaraj, and Youngsoo Lee. "Characterizing Spray-Dried Powders through NIR Spectroscopy: Effect of Two Preparation Strategies for Calibration Samples and Comparison of Two Types of NIR Spectrometers." Foods 12, no. 3 (2023): 467. http://dx.doi.org/10.3390/foods12030467.

Full text

Abstract:

Emerging portable near infrared (NIR) spectroscopic approaches coupled with data analysis and chemometric techniques provide opportunities for the rapid characterization of spray-dried products and process optimization. This study aimed to enhance the understanding of applying NIR spectroscopy in spray-dried samples by comparing two sample preparation strategies and two spectrometers. Two sets of whey protein–maltodextrin matrixes, one with a protein content gradient and one with a consistent protein content, were spray-dried, and the effect of the two preparation strategies on NIR calibration

APA, Harvard, Vancouver, ISO, and other styles

48

Chakrapani, Sneha B., Michael J. Minkler, and Bryan S. Beckingham. "Low-field 1H-NMR spectroscopy for compositional analysis of multicomponent polymer systems." Analyst 144, no. 5 (2019): 1679–86. http://dx.doi.org/10.1039/c8an01810c.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

P. Rueda, Marta, Ana Domínguez-Vidal, Víctor Aranda, and María José Ayora-Cañada. "Monitoring the Composting Process of Olive Oil Industry Waste: Benchtop FT-NIR vs. Miniaturized NIR Spectrometer." Agronomy 14, no. 12 (2024): 3061. https://doi.org/10.3390/agronomy14123061.

Full text

Abstract:

Miniaturized near-infrared (NIR) spectrometers are revolutionizing the agri-food industry thanks to their compact size and ultra-fast analysis capabilities. This work compares the analytical performance of a handheld NIR spectrometer and a benchtop FT-NIR for the determination of several parameters, namely, pH, electrical conductivity (EC25), C/N ratio, and organic matter as LOI (loss-on-ignition) in compost. Samples were collected at different stages of maturity from a full-scale facility that processes olive mill semi-solid residue together with olive tree pruning residue and animal manure.

APA, Harvard, Vancouver, ISO, and other styles

50

Wehlburg, Christine M., David M. Haaland, and David K. Melgaard. "New Hybrid Algorithm for Transferring Multivariate Quantitative Calibrations of Intra-Vendor Near-Infrared Spectrometers." Applied Spectroscopy 56, no. 7 (2002): 877–86. http://dx.doi.org/10.1366/000370202760171554.

Full text

Abstract:

A new prediction-augmented classical least-squares/partial least-squares (PACLS/PLS) hybrid algorithm is ideally suited for use in transferring multivariate calibrations between spectrometers. Spectral variations such as instrument response differences can be explicitly incorporated into the algorithm through the use of subset sample spectra collected on both spectrometers. Two current calibration transfer methods, subset recalibration and piecewise direct standardization (PDS), also utilize subset sample spectra to facilitate transfer of calibration. The three methods were applied to the tran

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!