Contact

Dr. Nikolai Avdievitch

Address: Spemannstr. 41
72076 Tübingen
Room number: 1.B.03
Phone: +49 7071 601 713
Fax: +49 7071 601 702
E-Mail: Nikolai.Avdievitch

 

Picture of Avdievitch, Nikolai, Dr.

Nikolai Avdievitch

Position: Senior Research Scientist  Unit: Henning Scheffler

Optimization of Transmit and Receive Performance of a Transceiver Phased Array

Motivation

In spite of great benefits offered by ultra-high field (UHF, > 7T) MRI, its further developments toward clinical applications are associated with significant technical issues, which include low transmit (Tx) efficiency and strong inhomogeneity of the RF magnetic field, B1+ (1). To improve Tx-efficiency and provide for a full coverage of the human brain, UHF multi-element multi-row arrays (2-6) have to be used in combination with 3D RF shimming or parallel transmission (pTx). There are two major types of human head array coils currently developed for the full-brain imaging at UHF. First type, a so called transmit-only/ receive-only (ToRo) array, consists of two nested layers of elements (5). Inner layer, which is positioned closer to a head, contains multiple elements (commonly loops) used only during reception, i.e. receive (Rx)-only elements. Larger array, positioned in the outer layer, provides for local transmission. Second design, a so called transceiver (TxRx) array, consists of a single layer of elements used during both transmission and reception (2-4,6). The Rx-performance of a human head coil can be easier optimized within the frame of the ToRo-design. Current state of the art UHF ToRo-arrays contain 30 and more Rx-only elements (5), which is critical for high SNR and parallel Rx-performance. In turn, TxRx-arrays provide for more efficient transmission, B1+/√P, due to tighter fit and, thus, higher tissue loading. TxRx-design is also simpler then the ToRo-design since it does not require detuning of elements. However, a drawback of the TxRx-design is that the number of elements in an array is limited by the number of available high power RF Tx-channels (commonly 8 or 16). My work focuses on development of new UHF arrays, which combine benefits of both designs, i.e. provide for efficient transmission and the same time do not compromise SNR and parallel receive performance.

Transmit efficiency

Previously we demonstrated that at 400 MHz a 16-loop double-row (2x8) tight-fit human head TxRx-array can be well decoupled entirely by overlapping surface loops without any additional decoupling strategy (7). This based on our analytical findings that at 400 MHz the mutual resistance between adjacent overlapped loops combined within this specific array geometry is minimal, and both the mutual inductance and mutual resistance can be minimized at the same time (8). As a result, the constructed 2x8 array demonstrated very good decoupling, a full brain coverage, and Tx-efficiency, which was 50% higher than that of the larger ToRo-array of similar length (7). Adding two perpendicular TxRx-loops at the superior position of a head (Fig.1A) improves uniformity of the array transmit B1+ profile (Fig.2).

Receive Performance

In the next step we developed a method of increasing the number of Rx-elements in a TxRx-array without compromising the array’s Tx-performance (9). First, we constructed a human head array prototype, which consisted of a single row of 8 TxRx surface loops circumscribing a head, and 8 Rx-only “vertical” loops positioned in the center of each TxRx-loop such to produce B1+ field perpendicularly to magnetic field B0 (similarly as in Fig.1B). All vertical loops were actively detuned during transmission and preamplifier decoupled during reception. Evaluation of the new array demonstrated that neither Tx-efficiency nor maximum SAR was compromised due to addition of Rx-only vertical loops (9). At the same time SNR was substantially improved (~30% near the brain center). Following prototyping 16-loop array, we extended this idea by constructing 32-element tight-fit human head array consisted of 18 TxRx-loops (Fig.1A) and 14 Rx-only vertical loops (Fig.1B) with the total number of Rx elements equal to 32. The general idea of this approach is that the total number of array elements should not exceed the number of available Rx-channels, i.e. 32 in our case. During designing, first, the required number (e.g. 18, Fig.1A) of TxRx-loops is placed around the object tightly to provide for high Tx-performance. Then, the rest of the loops are used as Rx-only elements, which are positioned to minimize interaction with the TxRx-loops, e.g. “vertically” (Fig.1B). In comparison to the common ToRo-design, this method preserves tight fit of the TxRx-loops and, thus, does not compromise the Tx-performance. In addition, it minimizes the total number of array elements as well as the number of active detuning circuits, which are not required for the TxRx-elements. As seen from Fig.3, the ToRo-array still provides for somewhat higher peripheral SNR.

At the same time, the new 32-channel tight-fit array has substantially (~30%) higher SNR near the center of the brain. It is well known that increasing the number of surface loops in a helmet human-head Rx-array only improves peripheral SNR, while SNR near the center practically doesn’t change (10,11). Combination of surface and vertical loops improves SNR near the center. Overall, the new tight-fit array demonstrates high SNR over the entire brain and a substantially more uniform SNR distribution than that of the ToRo-array. Both arrays provide for comparable Rx parallel performance.

References: 1) Vaughan JT et al, Magn Reson Med, 46:24-30, 2001. 2) Adriany G et al. Magn Reson Med 2010; 63(6):1478-1485. 3) Avdievich NI et al, Appl Magn Reson 2011, 41(2):483-506. 4) Gilbert KM et al, Magn Reson Med 2012;67:1487–1496. 5) Shajan G et al, Magn Reson Med, 71:870-879, 2014. 6) Avdievich NI et al, NMR in Biomedicine. 2017;30(2):1-12. 7) Avdievich et al, Proc. ISMRM 25, 2017, 759. 8) Avdievich et al, NMR in BioMed 2017, DOI: 10.1002/nbm.3759. 9) Avdievich et al, Proc. ISMRM 25, 2017, 4309. 10) Wiggins GC et al, Magn Reson Med 2009;62:754-762. 11) Vaidya MV et al, Conc Magn Reson Part B 2014; 44B(3):53–65.

Optimization of Transmit and Receive Performance of a Transceiver Phased Array

Motivation

In spite of great benefits offered by ultra-high field (UHF, > 7T) MRI, its further developments toward clinical applications are associated with significant technical issues, which include low transmit (Tx) efficiency and strong inhomogeneity of the RF magnetic field, B1+ (1). To improve Tx-efficiency and provide for a full coverage of the human brain, UHF multi-element multi-row arrays (2-6) have to be used in combination with 3D RF shimming or parallel transmission (pTx). There are two major types of human head array coils currently developed for the full-brain imaging at UHF. First type, a so called transmit-only/ receive-only (ToRo) array, consists of two nested layers of elements (5). Inner layer, which is positioned closer to a head, contains multiple elements (commonly loops) used only during reception, i.e. receive (Rx)-only elements. Larger array, positioned in the outer layer, provides for local transmission. Second design, a so called transceiver (TxRx) array, consists of a single layer of elements used during both transmission and reception (2-4,6). The Rx-performance of a human head coil can be easier optimized within the frame of the ToRo-design. Current state of the art UHF ToRo-arrays contain 30 and more Rx-only elements (5), which is critical for high SNR and parallel Rx-performance. In turn, TxRx-arrays provide for more efficient transmission, B1+/√P, due to tighter fit and, thus, higher tissue loading. TxRx-design is also simpler then the ToRo-design since it does not require detuning of elements. However, a drawback of the TxRx-design is that the number of elements in an array is limited by the number of available high power RF Tx-channels (commonly 8 or 16). My work focuses on development of new UHF arrays, which combine benefits of both designs, i.e. provide for efficient transmission and the same time do not compromise SNR and parallel receive performance.

Transmit efficiency

Previously we demonstrated that at 400 MHz a 16-loop double-row (2x8) tight-fit human head TxRx-array can be well decoupled entirely by overlapping surface loops without any additional decoupling strategy (7). This based on our analytical findings that at 400 MHz the mutual resistance between adjacent overlapped loops combined within this specific array geometry is minimal, and both the mutual inductance and mutual resistance can be minimized at the same time (8). As a result, the constructed 2x8 array demonstrated very good decoupling, a full brain coverage, and Tx-efficiency, which was 50% higher than that of the larger ToRo-array of similar length (7). Adding two perpendicular TxRx-loops at the superior position of a head (Fig.1A) improves uniformity of the array transmit B1+ profile (Fig.2).

Receive Performance

In the next step we developed a method of increasing the number of Rx-elements in a TxRx-array without compromising the array’s Tx-performance (9). First, we constructed a human head array prototype, which consisted of a single row of 8 TxRx surface loops circumscribing a head, and 8 Rx-only “vertical” loops positioned in the center of each TxRx-loop such to produce B1+ field perpendicularly to magnetic field B0 (similarly as in Fig.1B). All vertical loops were actively detuned during transmission and preamplifier decoupled during reception. Evaluation of the new array demonstrated that neither Tx-efficiency nor maximum SAR was compromised due to addition of Rx-only vertical loops (9). At the same time SNR was substantially improved (~30% near the brain center). Following prototyping 16-loop array, we extended this idea by constructing 32-element tight-fit human head array consisted of 18 TxRx-loops (Fig.1A) and 14 Rx-only vertical loops (Fig.1B) with the total number of Rx elements equal to 32. The general idea of this approach is that the total number of array elements should not exceed the number of available Rx-channels, i.e. 32 in our case. During designing, first, the required number (e.g. 18, Fig.1A) of TxRx-loops is placed around the object tightly to provide for high Tx-performance. Then, the rest of the loops are used as Rx-only elements, which are positioned to minimize interaction with the TxRx-loops, e.g. “vertically” (Fig.1B). In comparison to the common ToRo-design, this method preserves tight fit of the TxRx-loops and, thus, does not compromise the Tx-performance. In addition, it minimizes the total number of array elements as well as the number of active detuning circuits, which are not required for the TxRx-elements. As seen from Fig.3, the ToRo-array still provides for somewhat higher peripheral SNR. At the same time, the new 32-channel tight-fit array has substantially (~30%) higher SNR near the center of the brain. It is well known that increasing the number of surface loops in a helmet human-head Rx-array only improves peripheral SNR, while SNR near the center practically doesn’t change (10,11). Combination of surface and vertical loops improves SNR near the center. Overall, the new tight-fit array demonstrates high SNR over the entire brain and a substantially more uniform SNR distribution than that of the ToRo-array. Both arrays provide for comparable Rx parallel performance.

References: 1) Vaughan JT et al, Magn Reson Med, 46:24-30, 2001. 2) Adriany G et al. Magn Reson Med 2010; 63(6):1478-1485. 3) Avdievich NI et al, Appl Magn Reson 2011, 41(2):483-506. 4) Gilbert KM et al, Magn Reson Med 2012;67:1487–1496. 5) Shajan G et al, Magn Reson Med, 71:870-879, 2014. 6) Avdievich NI et al, NMR in Biomedicine. 2017;30(2):1-12. 7) Avdievich et al, Proc. ISMRM 25, 2017, 759. 8) Avdievich et al, NMR in BioMed 2017, DOI: 10.1002/nbm.3759. 9) Avdievich et al, Proc. ISMRM 25, 2017, 4309. 10) Wiggins GC et al, Magn Reson Med 2009;62:754-762. 11) Vaidya MV et al, Conc Magn Reson Part B 2014; 44B(3):53–65.

WORK EXPERIENCE:

Feb 2017-Current

Senior Research Scientist (100%), Institute of Physics, Ernst-Moritz-Arndt University Greifswald, Greifswald, Germany.

 

May. 2017-Current

Senior Research Scientist (20%), Department for Ultra-High Field MRI (Department chair Prof. K. Scheffler), Max Planck Institute for Biological Cybernetics, Tübingen, Germany.

 

Jan. 2013- Feb. 2017

Senior Research Scientist, Department for Ultra-High Field MRI (Department chair Prof. K. Scheffler), Max Planck Institute for Biological Cybernetics, Tübingen, Germany.

 

July 2012- Dec 2012

Senior RF Engineer, Resonance Research Instruments, Inc., Billerica, MA, USA.

 

Jan. 2007-June 2012

Associate Research Scientist, Magnetic Resonance Research Center, Department of Neurosergery, Yale University, New Haven, CT, USA.

 

Oct. 2000-Dec. 2006

Associate in Radiology, Magnetic Resonance Research Center, Department of Radiology, Albert Einstein Medical College, Bronx, NY, USA.

 

Feb. 1998-Oct. 2000

Electron Spin Resonance (ESR) Lab Manager, ESR Research Resource Center, Department of Physiology & Biophysics, Albert Einstein Medical College, Bronx, NY, USA.

 

1994-Feb. 1998

Postdoctoral Associate, Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.

 

1993-1994

Researcher, Laboratory of Spin and Magnetic Phenomena, International Tomography Center, Russian Academy of Science (Siberian Branch), Novosibirsk, Russia.

 

1992-1993

Researcher, Laboratory of Magnetic Phenomena, Institute of Chemical Kinetics and Combustion, Russian Academy of Science (Siberian Branch), Novosibirsk, Russia.

 

1987-1992

Junior Researcher, Laboratory of Magnetic Phenomena, Institute of Chemical Kinetics and  Combustion, Russian Academy of Science (Siberian Branch), Novosibirsk, Russia.

 

1985-1987

Engineer, Laboratory of Physical Methods of Chemical Kinetics, Institute of Chemical Kinetics and Combustion, Russian Academy of Science (Siberian Branch), Novosibirsk, Russia.

 

1983-1985

Research Technician, Laboratory of Physical Methods of Chemical Kinetics, Institute of Chemical Kinetics and Combustion, Russian Academy of Science (Siberian Branch), Novosibirsk, Russia.

 

EDUCATION:

1993

Ph.D. in Physical Chemistry, Institute of Chemical Kinetic and Combustion, Russian Academy of Science (Siberian Branch), Novosibirsk, Russia.

1985

M.S., Chemical Physics, Department of Physics, Novosibirsk State University, Novosibirsk, Russia.

1983

B.S., Radiophysics, Department of Physics, Novosibirsk State University, Novosibirsk, Russia.

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Show abstracts

Articles (52):

Avdievich NI, Giapitzakis IA, Pfrommer A, Borbáth T and Henning A (December-2017) Combination of surface and "vertical" loop elements improves receive performance of a human head transceiver array at 9.4 T NMR in Biomedicine Epub ahead.
Avdievich N, Pfrommer A, Giapitzakis IA and Henning A (October-2017) Analytical modeling provides new insight into complex mutual coupling between surface loops at ultrahigh fields NMR in Biomedicine 30(10) 1-13.
Fichtner ND, Giapitzakis I-A, Avdievich N, Mekle R, Zaldivar D, Henning A and Kreis R (October-2017) In vivo characterization of the downfield part of 1H MR spectra of human brain at 9.4T: Magnetization exchange with water and relation to conventionally determined metabolite content Magnetic Resonance in Medicine Epub ahead.
Zoelch N, Hock A, Heinzer-Schweizer S, Avdievitch N and Henning A (August-2017) Accurate determination of brain metabolite concentrations using ERETIC as external reference NMR in Biomedicine 30(8) 1-16.
Giapitzakis IA, Shao T, Avdievich NI, Mekle R, Kreis R and Henning A (August-2017) Metabolite-cycled STEAM and semi-LASER localization for MR spectroscopy of the human brain at 9.4T Magnetic Resonance in Medicine Epub ahead.
Giapitzakis IA, Avdievich NI and Henning A (July-2017) Characterization of macromolecular baseline at 9.4 T Magnetic Resonance in Medicine . submitted
Avdievich NI, Giapitzakis IA and Henning A (July-2017) Combined Surface Loop/"Vertical" Loop Element Improve Receive Performance of a Human Head Transceiver Array at 9.4T: an Alternative to Surface Loop/Dipole Antenna Combination NMR in Biomedicine . in revision
Avdievich NI, Giapitzakis I-A, Pfrommer A and Henning A (June-2017) Decoupling of a tight-fit transceiver phased array for human brain imaging at 9.4T: Loop overlapping rediscovered Magnetic Resonance in Medicine Epub ahead.
Avdievich NI, Hoffmann J, Shajan G, Pfrommer A, Giapitzakis IA, Scheffler K and Henning A (February-2017) Evaluation of transmit efficiency and SAR for a tight fit transceiver human head phased array at 9.4 T NMR in Biomedicine 30(2) 1-12.
Avdievich NI, Giapitzakis IA and Henning A (November-2016) Novel splittable N-Tx/2N-Rx transceiver phased array to optimize both signal-to-noise ratio and transmit efficiency at 9.4T Magnetic Resonance in Medicine 76(5) 1621-1628.
Hoffmann J, Henning A, Giapitzakis IA, Scheffler K, Shajan G, Pohmann R and Avdievich NI (September-2016) Safety testing and operational procedures for self-developed radiofrequency coils NMR in Biomedicine 29(9) 1131–1144.
Avdievich NI, Pan JW and Hetherington HP (November-2013) Resonant inductive decoupling (RID) for transceiver arrays to compensate for both reactive and resistive components of the mutual impedance NMR in Biomedicine 26(11) 1547–1554.
Pan JW, Dockrow RB, Spencer DD, Avidievich NI and Hetherington HP (February-2013) Selective homonuclear polarization transfer for spectroscopic imaging of GABA at 7T Magnetic Resonance in Medicine 69(2) 310–316.
Avdievich NI (December-2011) Transceiver-Phased Arrays for Human Brain Studies at 7 T Applied Magnetic Resonance 41(2-4) 483-506.
Pan JW, Avdievich N and Hetherington HP (November-2010) J-refocused coherence transfer spectroscopic imaging at 7 T in human brain Magnetic Resonance in Medicine 64(5) 1237–1246.
Avdievich NI, Oh S, Hetherington HP and Collins CM (August-2010) Improved homogeneity of the transmit field by simultaneous transmission with phased array and volume coil Journal of Magnetic Resonance Imaging 32(2) 476–481.
Hetherington HP, Avdievich NI, Kuznetsov AM and Pan JW (January-2010) F shimming for spectroscopic localization in the human brain at 7 T Magnetic Resonance in Medicine 63(1) 9–19.
Avdievich NI and Hetherington HP (November-2009) High-field head radiofrequency volume coils using transverse electromagnetic (TEM) and phased array technologies NMR in Biomedicine 22(9) 960–974.
Avdievich NI, Pan JW, Baehring JM, Spencer DD and Hetherington HP (July-2009) Short echo spectroscopic imaging of the human brain at 7T using transceiver arrays Magnetic Resonance in Medicine 62(1) 17–25.
Avdievich NI, Hetherington HP, Kuznetsov AM and Pan JW (February-2009) 7T head volume coils: Improvements for rostral brain imaging Journal of Magnetic Resonance Imaging 29(2) 461–465.
Bigal ME, Hetherington H, Pan J, Tsang A, Grosberg B, Avdievich N, Friedman B and Lipton RB (May-2008) Occipital levels of GABA are related to severe headaches in migraine Neurology 70(22) 2078–2080.
Avdievich NI, Bradshaw K, Lee J-H, Kuznetsov AM and Hetherington HP (August-2007) 4 T split TEM volume head and knee coils for improved sensitivity and patient accessibility Journal of Magnetic Resonance 187(2) 234–241.
Avdievich NI and Hetherington HP (June-2007) 4 T Actively detuneable double-tuned 1H/31P head volume coil and four-channel 31P phased array for human brain spectroscopy Journal of Magnetic Resonance 186(2) 341–346.
Avdievich NI, Bradshaw K, Kuznetsov AM and Hetherington HP (June-2007) High-field actively detuneable transverse electromagnetic (TEM) coil with low-bias voltage for high-power RF transmission Magnetic Resonance in Medicine 57(6) 1190–1195.
Avdievich NI, Peshkovsky AS, Kennan RP and Hetherington HP (October-2006) SENSE imaging with a quadrature half-volume transverse electromagnetic (TEM) coil at 4T Journal of Magnetic Resonance Imaging 24(4) 934–938.
Peshkovsky AS, Cerioni L, Osan TM, Avidievich NI and Pusiol DJ (September-2006) Three-dimensional high-inductance birdcage coil for NQR applications Solid State Nuclear Magnetic Resonance 30(2) 75–80.
Forbes MDE, Dukes KE, Avdievich NI, Harbron EJ and DeSimone JM (February-2006) Flexible Biradicals in Liquid and Supercritical Carbon Dioxide:  The Exchange Interaction, the Chain Dynamics, and a Comparison with Conventional Solvents Journal of Physical Chemistry A 110(5) 1767–1774.
Peshkovsky A, Kennan RP, Nagel RL and Avdievich NI (January-2006) Sensitivity enhancement and compensation of RF penetration artifact with planar actively detunable quadrature surface coil Magnetic Resonance Imaging 24(1) 81–87.
Peshkovsky AS, Kennan RP, Fabri ME and Avdievich NI (April-2005) Open half-volume quadrature transverse electromagnetic coil for high-field magnetic resonance imaging Magnetic Resonance in Medicine 53(4) 937–943.
Avdievich NI and Hetherington HP (December-2004) 4 T actively detunable transmit/receive transverse electromagnetic coil and 4-channel receive-only phased array for 1H human brain studies Magnetic Resonance in Medicine 52(6) 1459–1464.
Avdievich NI, Krymov VN and Hetherington HP (July-2003) Modified perturbation method for transverse electromagnetic (TEM) coil tuning and evaluation Magnetic Resonance in Medicine 50(1) 13–18.
Burns CS, Aronoff-Spencer E, Dunham CM, Lario P, Avdievich NI, Antholine WE, Olmstead MM, Vrielink A, Gerfen GJ, Peisach J, Scott WG and Millhauser GL (March-2002) Molecular Features of the Copper Binding Sites in the Octarepeat Domain of the Prion Protein Biochemistry 41(12) 3991-4001.
Avdievich NI and Gerfen GJ (December-2001) Multifrequency Probe for Pulsed EPR and ENDOR Spectroscopy Journal of Magnetic Resonance 153(2) 178–185.
Aronoff-Spencer E, Burns CS, Avdievich NI, Gerfen GJ, Pelsach J, Antholine WE, Ball HL, Cohen FE, Prusiner SE and Millhauser GL (November-2000) Identification of the Cu2+ Binding Sites in the N-Terminal Domain of the Prion Protein by EPR and CD Spectroscopy Biochemistry 39(45) 13760–13771.
Tsentalovich YP, Morozova OB, Avdievich NI, Ananchenko GS, Yurkovskaya AV, Ball JD and Forbes MDE (November-1997) Influence of Molecular Structure on the Rate of Intersystem Crossing in Flexible Biradicals Journal of Physical Chemistry A 101(47) 8809–8816.
Avdievich NI, Dukes KE, Forbes MDE and DeSimone JM (January-1997) Time-Resolved EPR Study of a 1,9-Flexible Biradical Dissolved in Liquid Carbon Dioxide. Observation of a New Spin-Relaxation Phenomenon:  Alternating Intensities in Spin-Correlated Radical Pair Spectra Journal of Physical Chemistry A 101(4) 617–621.
Forbes MDE, Schulz GE and Avdievich NI (October-1996) Unusual Dynamics of Micellized Radical Pairs Generated from Photochemically Active Amphiphiles Journal of the American Chemical Society 118(43) 10652–10653.
Forbes MDE, Avdievich NI, Ball JD and Schulz GR (August-1996) Chain Dynamics Cause the Disappearance of Spin-Correlated Radical Pair Polarization in Flexible Biradicals Journal of Physical Chemistry 100(33) 13887–13891.
Forbes MDE, Ball JD and Avdievich NI (May-1996) In Search of Through-Solvent Electronic Coupling in Flexible Biradicals Journal of the American Chemical Society 118(19) 4707–4708.
Avdievich NI, Jeevarajan AS and Forbes MDE (March-1996) Photoionization of N,N,N‘,N‘-Tetramethylphenylenediamine Studied by Q-Band Time-Resolved EPR Spectroscopy. Separation of Singlet and Triplet Ionization Channels Journal of Physical Chemistry 100(13) 5334–5342.
Avdievich NI and Forbes MDE (February-1996) Strong Modulation of the Exchange Interaction in a Spin-Polarized, Aryl Ether-Linked 1,14-Biradical Journal of Physical Chemistry 100(6) 1993–1995.
Jeevarajan AS, Kispert LD, Avdievich NI and Forbes MDE (January-1996) Role of Excited Singlet State in the Photooxidation of Carotenoids:  A Time-Resolved Q-Band EPR Study Journal of Physical Chemistry 100(2) 669–671.
Avdievich NI and Forbes MDE (June-1995) Dynamic Effects in Spin-Correlated Radical Pair Theory: J Modulation and a New Look at the Phenomenon of Alternating Line Widths in the EPR Spectra of Flexible Biradicals Journal of Physical Chemistry 99(24) 9660–9667.
Tarasov VF, Bagranskaya EG, Shkrob IA, Avdievich NI, Ghatlia ND, Lukzen NN, Turro NJ and Sagdeev RZ (January-1995) Examination of the Exchange Interaction through Micellar Size. 3. Stimulated Nuclear Polarization and Time Resolved Electron Spin Resonance Spectra from the Photolysis of Methyldeoxybenzoin in Alkyl Sulfate Micelles of Different Sizes Journal of the American Chemical Society 117(1) 110–118.
Tarasov VF, Ghatila ND, Avdievich NI, Shkrob IA, Buchachenko AL and Turro NJ (March-1994) Examination of the Exchange Interaction through Micelle Size. 2. Isotope Separation Efficiency as an Experimental Probe Journal of the American Chemical Society 116(6) 2281–2291.
Polyakov NE, Taraban MB, Kruppa AI, Avdievich NI, Mokrushin VV, Schastnev PV, Leshina TV, Lüsis V, Muceniece D and Duburs G (August-1993) The mechanisms of oxidation of NADH analogues 3. Stimulated nuclear polarization (SNP) and chemically induced dynamic nuclear polarization (CIDNP) in low magnetic fields in photo-oxidation reactions of 1,4-dihydropyridines with quinones Journal of Photochemistry and Photobiology A: Chemistry 74(1) 75-79.
Tarasov VF, Ghatlia ND, Avdievich NI and Turro NJ (January-1993) Exchange Interaction in Micellized Radical Pairs Zeitschrift für Physikalische Chemie 182(1-2) 227–244.
Avdievich NI, Bagryanskaya EG, Tarasov VF and Sagdeev RZ (January-1993) Investigation of Micellized Radical Pairs in the Photolysis of Ketones by Time-Resolved Stimulated Nuclear Polarization Zeitschrift für Physikalische Chemie 182(1-2) 107–117.
Bagryanskaya EG, Tarasov VF, Avdievich NI and Shkrob IA (May-1992) Electron spin exchange in micellized radical pairs. III. 13C low-field ratio frequency stimulated nuclear polarization spectroscopy (LF SNP) Chemical Physics 162(1) 213–223.
Bagryanskaya EG, Avdievich NI, Grishin YA and Sagdeev RZ (July-1989) The study of microwave-induced nuclear polarization in the sensitized trans-cis isomerization of fumaronitrile Chemical Physics 135(1) 123–129.
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