Journal articles: 'Electron spin resonance (ESR)'

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Kameya, Hiromi. "ESR (Electron Spin Resonance)." Nippon Shokuhin Kagaku Kogaku Kaishi 60, no. 4 (2013): 198. http://dx.doi.org/10.3136/nskkk.60.198.

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Shimada, Shigetaka. "ESR(Electron Spin Resonance)." Kobunshi 40, no. 10 (1991): 700–703. http://dx.doi.org/10.1295/kobunshi.40.700.

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TSUJITA, Takahiro, and Shingo OKAMOTO. "Electron Spin Resonance." Journal of the Japan Society of Colour Material 69, no. 6 (1996): 413–21. http://dx.doi.org/10.4011/shikizai1937.69.413.

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Grün, Rainer. "Electron spin resonance (ESR) dating." Quaternary International 1 (January 1989): 65–109. http://dx.doi.org/10.1016/1040-6182(89)90010-4.

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Bojanowski, Bohdan, and Sławomir Kaczmarek. "Electron spin resonance of FeVO4." Materials Science-Poland 32, no. 2 (June 1, 2014): 188–92. http://dx.doi.org/10.2478/s13536-013-0192-7.

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AbstractWe report on electron spin resonance (ESR) investigations of a FeVO4 single crystal. Temperature and angular dependences of ESR resonance positions were measured and calculated in temperature range of 35–100 K. The spectra show rich angular dependences of the linewidth, the shape and the resonance field. They consist of a single broad line with asymmetric distortion. Due to the low symmetry of the crystal lattice this distortion can be explained by taking into account the influence of non diagonal dynamic susceptibility.

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Poirot, Nathalie, Cécile Autret-Lambert, and Raquel A. Souza. "Electron Spin Resonance of Nickelate." Advances in Science and Technology 67 (October 2010): 206–11. http://dx.doi.org/10.4028/www.scientific.net/ast.67.206.

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In the present study we focused on the nickelate system, which presents stable stripe order and allow a large domain of oxygen doping. More specifically, we studied the non-stoichiometric system La2NiO4 in which the oxygen excess tends to order. ESR technique has been used due to its sensibility to microscopic magnetic fluctuations. We present a systematic study of the charge and spin fluctuations in oxygen doped nickelates to get insight into the dynamic of the system using ESR. The intrinsic resonance signal of polycrystalline La2NiO4 - values 0.09 and 0.12 have been studied, in a large temperature range (10K < T < 300 K). The = 0.12 compound has been chosen as a starting point, since neutron diffraction studies in composition very close to this value have been well characterized the stripe order in this system, showing that the holes order at around TCO = 200K, while the spins order at TS = 110K. By analogy, the ESR results on this compound allowed us to interpret the results in the other compound.

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Moreno, N. O., J. G. S. Duque, P. G. Pagliuso, C. Rettori, R. R. Urbano, and T. Kimura. "Electron spin resonance (ESR) in multiferroic." Journal of Magnetism and Magnetic Materials 310, no. 2 (March 2007): e364-e366. http://dx.doi.org/10.1016/j.jmmm.2006.10.281.

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Crăciun, C., and Aurelia Meghea. "Electron spin resonance studies of montmorillonites." Clay Minerals 20, no. 3 (September 1985): 281–90. http://dx.doi.org/10.1180/claymin.1985.020.3.01.

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AbstractSixteen montmorillonites (8 normal and 8 abnormal using DTA dehydroxylation criteria) from the Gurasada bentonite deposits, Romania, were investigated by ESR. The spectra showed two features: a g = 4·3 signal attributed to isolated Fe3+ ions and a broad resonance with g ∼ 2·0 which was interpreted as arising from exchange interactions between clusters of Fe3+ ions. Additional experiments suggested that the latter resonance could have a structural component. The line-shape of the two resonances varied between normal and abnormal montmorillonites, indicating that the distribution of the Fe3+ ions between internal phase (montmorillonite lattice) and external phase (montmorillonite surface) was different for the two varieties.

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Kajiwara, Atsushi. "Characterizations of radicals formed in radical polymerizations and transfer reactions by electron spin resonance spectroscopy." Pure and Applied Chemistry 90, no. 8 (August 28, 2018): 1237–54. http://dx.doi.org/10.1515/pac-2018-0401.

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Abstract Electron spin resonance (ESR, aka electron paramagnetic resonance, EPR) investigations have been conducted on radicals formed during radical polymerizations and provide a detailed characterization of the active radical species. Active propagating radicals can be observed during actual radical polymerizations by ESR/EPR. The chain lengths of the observed radicals were estimated by a combination of atom transfer radical polymerization (ATRP) and ESR/EPR. The structures of the chain end radicals were determined by analysis of the ESR/EPR spectra. An increase in the dihedral angles between terminal p-orbital of radical and Cβ–H bonds was observed with increasing chain lengths of methacrylate polymers. Radical transfer reactions were observed during radical polymerization of acrylates. A combination of ATRP and ESR/EPR clarified a 1,5-hydrogen shift mechanism of the radical transfer reactions using model adamantyl acrylate radicals. Penultimate unit effects were also observed. Time-resolved ESR/EPR (TR ESR) spectroscopy clarified the initiation processes of an alternating copolymerization of styrene with maleic anhydride and the copolymerization of styrene with 1,3-butadiene. Several unsolved problems in conventional radical polymerization processes have been clarified using combinations of ATRP with ESR/EPR and TR ESR. Characterization of the radicals in radical polymerizations using various ESR techniques would definitely provide interesting and useful information on conventional radical polymerizations.

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Drescher, Malte. "Functional and Highly Spatially Resolved ESR Imaging." Australian Journal of Chemistry 58, no. 1 (2005): 26. http://dx.doi.org/10.1071/ch04235.

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Electron spin resonance imaging is a technique using similar principles to the established nuclear magnetic resonance imaging; however, the very fast electron-spin relaxation time constants of the former are an experimental challenge. In order to obtain T2-weighted as well as functional images spatially resolved in the micrometer range, we use temperature-dependent pulsed X-band ESR and the back-projection reconstruction method. We present here recent results of our imaging project focussing on quasi one-dimensional organic conductors, where even pulsed conduction electron-spin resonance is possible.

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Kitagawa, Akio. "Electron Spin Resonance Measurement with Microinductor on Chip." Journal of Sensors 2011 (2011): 1–3. http://dx.doi.org/10.1155/2011/813636.

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The detection of radicals on a chip is demonstrated. The proposed method is based on electron spin resonance (ESR) spectroscopy and the measurement of high-frequency impedance of the microinductor fabricated on the chip. The measurement was by using a frequency sweep of approximately 100 MHz. The ESR spectra of di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) dropped on the microinductor which is fabricated with CMOS 350-nm technology were observed at room temperature. The volume of the DPPH ethanol solution was 2 μL, and the number of spins on the micro-inductor was estimated at about 1014. The sensitivity is not higher than that of the standard ESR spectrometers. However, the result indicates the feasibility of a near field radical sensor in which the microinductor as a probe head and ESR signal processing circuit are integrated.

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Semeno, A. V., V. V. Glushkov, A. V. Bogach, N. E. Sluchanko, A. V. Dukhnenko, V. B. Fillippov, N. Y. Shitsevalova, and S. V. Demishev. "Electron Spin Resonance in EuB₆." Solid State Phenomena 152-153 (April 2009): 349–52. http://dx.doi.org/10.4028/www.scientific.net/ssp.152-153.349.

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Cavity measurements of a high frequency (60 GHz) electron spin resonance (ESR) have been carried our for a single crystal of EuB6 at temperatures 4.2-50K in magnetic field up to 7 T, which has been aligned along [001] crystallographic direction. The influence of the experimental geometry on the parameters of the resonance line has been studied. It is found that in conditions of a homogeneous magnetic field the ESR spectrum in EuB6 is formed by a single resonance line at all temperatures including the ferromagnetic ordering region. The presence of the gradient of the magnetic field in the sample causes strong broadening of the resonance line at low temperatures and even may induce a double peak ESR structure. The analysis of the linewidth temperature dependence in EuB6 shows the anomalous growth of the line width below Curie temperature TC ~15 K.

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Chaikum, N., and R. M. Carr. "Electron spin resonance studies of halloysites." Clay Minerals 22, no. 3 (September 1987): 287–96. http://dx.doi.org/10.1180/claymin.1987.022.3.03.

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AbstractAbsorption lines in the g ∼ 4 region of ESR spectra of three New Zealand halloysites were found to originate from similar paramagnetic centres as in kaolinites. Resonances in the g ∼ 4 region were not common to all the halloysites, although the signal at g = 2·0 for the Matauri Bay halloysite is probably due to a trapped positive hole or trapped ion. A 6-line resonance produced by Te Puke halloysite and removable by Na-saturation is attributed to exchangeable Mn on the clay surface. Low-temperature lines exhibited by all samples are due to V4+ or VO2+ replacing Al3+ in the octahedral sheet.

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NAKAI, Yumi. "Foundation and Aplication of Electron Spin Resonance." Journal of the Japan Society of Colour Material 78, no. 11 (2005): 539–45. http://dx.doi.org/10.4011/shikizai1937.78.539.

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Khamlich, S., V. V. Srinivasu, A. Konkin, N. Cingo, F. T. Thema, A. Benyoussef, and M. Maaza. "Photoinduced Electron Spin Resonance Phenomenon inα-Cr2O3Nanospheres." Journal of Nanomaterials 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/831065.

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The photoinduced phenomenon inα-Cr2O3nanoscaled spherical particles was investigated in the temperature range of 150 up to 315 K. An X-band electron-spin resonance spectrometry was employed to probe the magnetic behavior inα-Cr2O3under an IR illumination in the nanosecond regime. The photoinduced effect on both low and high field ESR signals appears above 280 K and is remarkably enhanced just below Néel temperatureTN. Such a photoinduced ESR phenomenon disappears in a reproducible way in the paramagnetic insulating state which occurs aboveTNof crystallineα-Cr2O3. In the antiferromagnetic phase, that is, belowTN, the shift of the low field absorption could be attributed to the interaction of the light with specific Cr3+ions located in strongly distorted sites correlated to strong ligand-field effect.

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Bingham, Stephen J., Daniel Wolverson, and Andrew J. Thomson. "Coherent Raman detected electron spin resonance spectroscopy of metalloproteins: linking electron spin resonance and magnetic circular dichroism." Biochemical Society Transactions 36, no. 6 (November 19, 2008): 1187–90. http://dx.doi.org/10.1042/bst0361187.

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The simultaneous excitation of paramagnetic molecules with optical (laser) and microwave radiation in the presence of a magnetic field can cause an amplitude, or phase, modulation of the transmitted light at the microwave frequency. The detection of this modulation indicates the presence of coupled optical and ESR transitions. The phenomenon can be viewed as a coherent Raman effect or, in most cases, as a microwave frequency modulation of the magnetic circular dichroism by the precessing magnetization. By allowing the optical and magnetic properties of a transition metal ion centre to be correlated, it becomes possible to deconvolute the overlapping optical or ESR spectra of multiple centres in a protein or of multiple chemical forms of a particular centre. The same correlation capability also allows the relative orientation of the magnetic and optical anisotropies of each species to be measured, even when the species cannot be obtained in a crystalline form. Such measurements provide constraints on electronic structure calculations. The capabilities of the method are illustrated by data from the dimeric mixed-valence CuA centre of nitrous oxide reductase (N2OR) from Paracoccus pantotrophus.

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Al-Mowali, Ali H., and Alhan D. Girgees. "Electron Spin Resonance Linewidth Studies of Vanadyl Tetraphenylporphyrin." Collection of Czechoslovak Chemical Communications 58, no. 6 (1993): 1294–98. http://dx.doi.org/10.1135/cccc19931294.

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The linewidths of the hyperfine components of the ESR spectra of vanadyl tetraphenylporphyrin in liquid toluene have been measured as a function of temperature and analyzed in detail. This has allowed the separate contributions to the observed ESR line widths from spin rotational, g tensor anisotropy, hyperfine anisotropy and unresolved nitrogen hyperfine coupling to be evaluated. These results have been used to estimate the size of the nitrogen isotropic hyperfine coupling constant and thus the extent of delocalization of the unpaired electron onto the nitrogen atoms.

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Ito, Shinobu, Tomohisa Mori, Hideko Kanazawa, and Toshiko Sawaguchi. "Estimation of the Postmortem Duration of Mouse Tissue by Electron Spin Resonance Spectroscopy." Journal of Toxicology 2011 (2011): 1–11. http://dx.doi.org/10.1155/2011/973172.

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Electron spin resonance (ESR) method is a simple method for detecting various free radicals simultaneously and directly. However, ESR spin trap method is unsuited to analyze weak ESR signals in organs because of water-induced dielectric loss (WIDL). To minimize WIDL occurring in biotissues and to improve detection sensitivity to free radicals in tissues, ESR cuvette was modified and used with 5,5-dimethtyl-1-pyrroline N-oxide (DMPO). The tissue samples were mouse brain, hart, lung, liver, kidney, pancreas, muscle, skin, and whole blood, where various ESR spin adduct signals including DMPO-ascorbyl radical (AsA∗), DMPO-superoxide anion radical (OOH), and DMPO-hydrogen radical (H) signal were detected. Postmortem changes in DMPO-AsA∗and DMPO-OOH were observed in various tissues of mouse. The signal peak of spin adduct was monitored until the 205th day postmortem. DMPO-AsA∗in liver (y=113.8–40.7 log (day),R1=-0.779,R2=0.6,P<.001) was found to linearly decrease with the logarithm of postmortem duration days. Therefore, DMPO-AsA∗signal may be suitable for detecting an oxidation stress tracer from tissue in comparison with other spin adduct signal on ESR spin trap method.

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Khramtsov, Valery V., Igor A. Grigor’ev, David J. Lurie, Margaret A. Foster, Jay L. Zweier, and Periannan Kuppusamy. "Spin pH and SH probes: enhancing functionality of EPR-based techniques." Spectroscopy 18, no. 2 (2004): 213–25. http://dx.doi.org/10.1155/2004/870630.

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Along with significant progress in low-frequency electron spin resonance (ESR, also called electron paramagnetic resonance, EPR), other techniques such as Longitudinally-Detected ESR (LODESR), proton electron double-resonance imaging (PEDRI) and field-cycled dynamic nuclear polarization (FC-DNP) have been developed forin vivoapplications. However their potential is still far from maximally defined, in part, because of the need for new specific function-directed spin probes. An application of stable nitroxides of imidazoline and imidazolidine types provides unique possibility to measure local values of pH and thiol content in various biological systems, includingin vivostudies. These applications are based on the observation of specific chemical reactions of these nitroxides with protons or thiols, followed by significant changes in their EPR spectra. To increase sensitivity of pH probes for low-frequency EPR spectroscopy we evaluated two alternative approaches: (i) application of isotopically substituted labels, and (ii) acquisition of EPR spectra at high modulation amplitude. Spatial and spectral-spatial imaging (pH-mapping) using PEDRI and L-band EPR imagers were performed both on phantom samples andin vivo. The applications of the pH and SH probes in model systems, biological fluids, andin vivoin living animals are discussed.

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IKETANI, MOTOMI. "Electron spin resonance (ESR) and petroleum mining industry." Journal of the Japanese Association for Petroleum Technology 51, no. 1 (1986): 87–93. http://dx.doi.org/10.3720/japt.51.87.

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Ikeya, M. "Electron Spin Resonance (ESR) Microscopy in Materials Science." Annual Review of Materials Science 21, no. 1 (August 1991): 45–63. http://dx.doi.org/10.1146/annurev.ms.21.080191.000401.

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Raghunathan, P., and L. Kevan. "Electron spin resonance and electron spin echo spectroscopic studies of Cu2+ sites in synthetic cancrinite zeolites." Canadian Journal of Chemistry 66, no. 8 (August 1, 1988): 1984–88. http://dx.doi.org/10.1139/v88-320.

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Electron spin resonance (ESR) and electron spin echo modulation (ESEM) studies of Cu2+ sites introduced by ion exchange are reported in two types of synthetic cancrinite zeolites, one of them a more hydrated sample, Na6 Al6Si6O24•8H2O (denoted C1), and the other a less hydrated sample with entrained calcium carbonate, Na6Al6Si6O24•CaCO3•8H2O (denoted C2). ESR spectra reveal that C1 activated at 100 °C contains Cu2+ sites of tetrahedral symmetry with [Formula: see text] and [Formula: see text] while at a higher activation temperature of 400 °C Cu2+ sites with a different symmetry are produced corresponding to [Formula: see text] and [Formula: see text] C2 activated at 100 °C contains almost exclusively Cu2+ sites of trigonal symmetry with [Formula: see text] and [Formula: see text] Two- and three-pulse ESEM experiments at 4 K give 2D and 27Al modulation patterns that corroborate these ESR assignments. Possible locations of the Cu2+ sites in the C1 and C2 structures are proposed.

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Hutton, DR, JR Pilbrow, GJ Troup, and JO Warne. "Electron Spin Resonance of Ti3+ in Synthetic Beryl." Australian Journal of Physics 45, no. 2 (1992): 253. http://dx.doi.org/10.1071/ph920253.

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Grün, Rainer, Henry P. Schwarcz, and Steve Zymela. "Electron spin resonance dating of tooth enamel." Canadian Journal of Earth Sciences 24, no. 5 (May 1, 1987): 1022–37. http://dx.doi.org/10.1139/e87-099.

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The amplitude of the electron spin resonance (ESR) peak at g = 2.0018 for hydroxyapatite of fossil tooth enamel can be used to measure the acquired radiation dose (AD) and thus the time (T) since burial of the tooth in a sediment. No significant fading or saturation occurs up to at least 1 Ma, permitting dating of middle Pleistocene deposits. AD is determined by the additive-dose method, using a sufficiently large modulation amplitude to avoid the interference of organic free radicals, and a logarithmic transformation of the ESR intensity to correct for saturation effects. AD increases through time as a result of (1) constant irradiation by U, K, and Th in the surrounding sediment and by cosmic rays; (2) external irradiation by beta particles from U in the dentine; and (3) alpha and beta particles from U in the enamel. We derive an expression for AD(T) taking into account (1) approach to equilibrium between U and its long-lived daughters; and (2) T-dependent (early or linear) uptake of U by dentine or cement and by enamel, as well as the constant environmental radiation sources. T is determined by iteratively solving this expression to obtain the observed AD. An example is given of the dating of an elephant tooth from a preglacial deposit in Alberta: the calculated age is consistent with assignment to isotope stages 5c–5e.

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Hwang, Jiyoon, Denis Krylov, Robbie Elbertse, Sangwon Yoon, Taehong Ahn, Jeongmin Oh, Lei Fang, et al. "Development of a scanning tunneling microscope for variable temperature electron spin resonance." Review of Scientific Instruments 93, no. 9 (September 1, 2022): 093703. http://dx.doi.org/10.1063/5.0096081.

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Recent advances in improving the spectroscopic energy resolution in scanning tunneling microscopy (STM) have been achieved by integrating electron spin resonance (ESR) with STM. Here, we demonstrate the design and performance of a homebuilt STM capable of ESR at temperatures ranging from 1 to 10 K. The STM is incorporated with a homebuilt Joule–Thomson refrigerator and a two-axis vector magnet. Our STM design allows for the deposition of atoms and molecules directly into the cold STM, eliminating the need to extract the sample for deposition. In addition, we adopt two methods to apply radio-frequency (RF) voltages to the tunnel junction: the early design of wiring to the STM tip directly and a more recent idea to use an RF antenna. Direct comparisons of ESR results measured using the two methods and simulations of electric field distribution around the tunnel junction show that, despite their different designs and capacitive coupling to the tunnel junction, there is no discernible difference in the driving and detection of ESR. Furthermore, at a magnetic field of ∼1.6 T, we observe ESR signals (near 40 GHz) sustained up to 10 K, which is the highest temperature for ESR-STM measurement reported to date, to the best of our knowledge. Although the ESR intensity exponentially decreases with increasing temperature, our ESR-STM system with low noise at the tunnel junction allows us to measure weak ESR signals with intensities of a few fA. Our new design of an ESR-STM system, which is operational in a large frequency and temperature range, can broaden the use of ESR spectroscopy in STM and enable the simple modification of existing STM systems, which will hopefully accelerate a generalized use of ESR-STM.

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Walzak, Mary Jane, and John R. Harbour. "Electron spin resonance detection of heterogeneous reactions of Pigment Red 122." Canadian Journal of Chemistry 68, no. 4 (April 1, 1990): 640–43. http://dx.doi.org/10.1139/v90-098.

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Electron spin resonance spectroscopy (ESR) has been used to investigate the electrochemical and photolytic behaviour of particulate C.I. Pigment Red 122. Heterogeneous electrochemical reduction and oxidation of the pigment resulted in different reversible ESR signals with the radical cation giving a signal of ΔHpp = 2.3 G and g-factor of 2.0033 and the radical anion giving ΔHpp = 3.2 G and g-factor 2.0039. On exposure to light the inherent ESR signal, which was determined to be a two-component signal, increased in intensity by a factor of 2.4 but did not change in linewidth or g-factor. This light-induced signal was reversible and decayed to initial levels in the dark. The mechanism of these reactions is discussed. Keywords: ESR, pigment, electrochemistry, photo effects.

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Ohta, H., S. Okubo, H. Kikuchi, and S. Ono. "Millimetre-wave ESR (electron-spin resonance) measurements of frustrated system ZnCr2xGa22xO4." Canadian Journal of Physics 79, no. 11-12 (December 1, 2001): 1387–91. http://dx.doi.org/10.1139/p01-089.

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The magnetic properties of a three-dimensional topological frustrated system ZnCr2xGa2-2xO4, which is an anti-ferromagnet with a spinel structure, have been investigated by our millimetre-wave ESR (electron-spin resonance) measurements using the pulsed magnetic field up to 16 T in the temperature region from 1.8 to 265 K. In the high-temperature region, typical Cr3+ EPR (electron-paramagnetic resonance) with the g-value of 1.95 was observed. For the x = 1 sample, AFMR (anti-ferromagnetic resonance) with the easy-plane-type magnetic anisotropy was observed below TN. It turned out that the anti-ferromagnetic gap opens up just below TN suggesting that the transition is of the first order. The x dependences of ESR were also observed and their temperature dependences of the g-value and the linewidth will be discussed in connection with those of other frustrated systems such as Kagome lattice substance. PACS Nos.: 75.50, 76.30-v, 75.40-s

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MISRA, A. P., G. BRODIN, M. MARKLUND, and P. K. SHUKLA. "Circularly polarized modes in magnetized spin plasmas." Journal of Plasma Physics 76, no. 6 (September 2, 2010): 857–64. http://dx.doi.org/10.1017/s0022377810000450.

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AbstractThe influence of the intrinsic spin of electrons on the propagation of circularly polarized waves in a magnetized plasma is considered. New eigenmodes are identified, one of which propagates below the electron cyclotron frequency, one above the spin-precession frequency, and another close to the spin-precession frequency. The latter corresponds to the spin modes in ferromagnets under certain conditions. In the non-relativistic motion of electrons, the spin effects become noticeable even when the external magnetic field B0 is below the quantum critical magnetic field strength, i.e. B0 < BQ = 4.4138 × 109T and the electron density satisfies n0 ≫ nc ≃ 1032m−3. The importance of electron spin (paramagnetic) resonance (ESR) for plasma diagnostics is discussed.

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BERG, A., D. WEISS, K. V. KLITZING, and R. NÖTZEL. "SPIN SPLITTING IN A TWO DIMENSIONAL ELECTRON SYSTEM DETERMINED BY NUCLEAR MAGNETIC RELAXATION AND MAGNETOTRANSPORT ACTIVATION MEASUREMENTS." International Journal of Modern Physics B 07, no. 01n03 (January 1993): 474–79. http://dx.doi.org/10.1142/s0217979293000998.

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The spin splitting observed in two-dimensional electron systems at high magnetic fields is not only determined by the single-electron Zeeman energy but also by many-particle effects. Electron-electron interaction results in an enhanced g-factor which can be described by the exchange part of the Coulomb interaction. Nuclear spin lattice relaxation experiments analysing the Overhauser Shift in Electron Spin Resonance (ESR) measurements reveal that the exchange term is dominant. The spin splitting is strongly dependent on magnetic field and temperature. Numerical simulations enable the quantitative determination of the exchange part of the spin split energy. Transport activation measurements verify that the exchange part is proportional to the spin polarization of the electrons.

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Jain, Manu. "Electron Spin Resonance Of Vo2+ In Likso4 Single Crystals." Zeitschrift für Naturforschung A 59, no. 7-8 (August 1, 2004): 488–90. http://dx.doi.org/10.1515/zna-2004-7-813.

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Electron spin resonance of VO2+ doped in LiKSO4 single crystals has been studied at 295 K, using an X-band spectrometer. Three sites have been observed. VO2+ enters the lattice at Li and K substitutional sites. The ESR spectra have been analysed and spin-Hamiltonian parameters evaluated. PACS: 76.30 F

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Zhang, Feng, Zhiyu Sun, and Jianguo Cui. "Research on the mechanism and reaction conditions of electrochemical preparation of persulfate in a split-cell reactor using BDD anode." RSC Advances 10, no. 56 (2020): 33928–36. http://dx.doi.org/10.1039/d0ra04669h.

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Through cyclic voltammetry (CV) curve, electron spin resonance spectroscopy (ESR) characterization and free radical competitive trapping experiment, an analysis was performed on the mechanism of persulfate (PDS) electro-synthesis by sulfate at boron-doped diamond (BDD) anode.

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Rech, Amanda Burg, Angela Kinoshita, Paulo Marcos Donate, Otaciro Rangel Nascimento, and Oswaldo Baffa. "Electron Spin Resonance Dosimetry Studies of Irradiated Sulfite Salts." Molecules 27, no. 20 (October 19, 2022): 7047. http://dx.doi.org/10.3390/molecules27207047.

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The study of new materials for radiation dosimetry is important to improve the present state of the art and to help in cases of accidents for retrospective dosimetry. Sulfites are compounds that contain a sulfur ion, widely used in the food industry. Due to the significant application of these compounds, sulfites are interesting candidates for accidental dosimetry, as fortuitous radiation detectors. The presence of the SO3− anion enables its detection by electron spin resonance (ESR) spectroscopy. The Dose–Response behavior, signal stability and other spectral features were investigated for sodium sulfite, sodium bisulfite, sodium metabisulfite and potassium metabisulfite, all in crystalline forms. The ESR spectrum of salts presented stability and proportional response with dose, presenting potential for dosimetry applications.

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Radtke, Ulrich, Rainer Grün, and Henry P. Schwarcz. "Electron Spin Resonance Dating of the Pleistocene Coral Reef Tracts of Barbados." Quaternary Research 29, no. 3 (May 1988): 197–215. http://dx.doi.org/10.1016/0033-5894(88)90030-0.

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The reef tracts of Barbados have been investigated by electron spin resonance dating; all parameters necessary for ESR dating (including effective α-efficiency and thermal stability) were determined without cross checking with another independent dating method. In addition, some U-series analyses were carried out in order to test the reliability of ESR. In most cases, the results show a satisfactory agreement between ESR and both these and previously published U-series dates (M. L. Bender, R. G. Fairbanks, F. W. Taylor, R. K. Matthews, J. G. Goddard, and W. S. Broecker (1979). Geological Society of America. Bulletin 90 , 577–594). For the oldest samples, ESR dates tend to exceed He/U dates, suggesting that there might have been He loss from aragonite. Raised reef tracts are assigned to high sea stands from successive interglacial stages 5, 7, 9, 11, 13, and 15. ESR and U-series (230Th/234U) dates for corals and molluses in North Barbados do not support the suggestion of N. P. James ((1971). Unpublished Thesis, McGill University, Montreal) that this region has subsided during part of the past 125,000 yr. Whereas the experimentally determined mean life (τ) of trapped electrons is only 500,000 yr for the ambient temperature in Barbados, there is no evidence from the comparison between ESR and other dates for thermal fading. This emphasizes the difficulty of experimental measurement of τ.

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Chipara, Mircea, William J. Brittain, Kin-tak Lau, and Magdalena Dorina Chipara. "Polycarbonate-Carbon Nanofibers Composites: An Electron Spin Resonance Study." Polymers and Polymer Composites 16, no. 8 (October 2008): 519–26. http://dx.doi.org/10.1177/096739110801600805.

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Electron spin resonance investigations on polycarbonate loaded with various amounts of carbon nanofibers (ranging from 0% to 10%) are reported. A complex resonance spectrum was recorded. The spectrum was assigned to the convolution of resonance lines originating from the conducting electrons delocalized over the metallic domains of nanotubes, of free radicals generated during the polymer processing, and of catalyst's traces. The shape of resonance spectra originating from conducting electrons delocalized over the metallic domains of nanotubes was accurately fitted by a Lorentzian-like shape. The correlation between the measured DC resistivity of these samples and the relevant parameters of the resonance spectrum (line width, g-factor, and ratio between the amplitude of the absorption and dispersion components) was investigated. The saturation of the ESR line, at room temperature is reported.

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35

SAKAWA, Mitsuhiro. "Coal study by means of Electron Spin Resonance (ESR)." Journal of the Fuel Society of Japan 64, no. 11 (1985): 897–910. http://dx.doi.org/10.3775/jie.64.11_897.

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36

KOJIMA, Takuji, and Ryuichi TANAKA. "High-Dose Dosimetry Using Electron Spin Resonance(ESR) Spectroscopy." RADIOISOTOPES 41, no. 6 (1992): 320–30. http://dx.doi.org/10.3769/radioisotopes.41.6_320.

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37

Holanda, L. M., J. M. Vargas, C. Rettori, P. G. Pagliuso, E. M. Bittar, M. A. Avila, and T. Takabatake. "Electron spin resonance (ESR) ofEu2+in type-I clathrateEu8Ga16Ge30." Physica B: Condensed Matter 404, no. 19 (October 2009): 3300–3303. http://dx.doi.org/10.1016/j.physb.2009.07.094.

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38

Kordas, G., R. A. Weeks, and L. C. Klein. "Electron-spin-resonance (ESR) study of sol-gel glasses." Journal of Non-Crystalline Solids 71, no. 1-3 (May 1985): 327–33. http://dx.doi.org/10.1016/0022-3093(85)90303-5.

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39

Martinez, L. M., M. D. Teran, R. R. Chianelli, S. R. J. Hennadige, and S. R. Singamaneni. "Magnetic Defects in Transitional Metal Di-Chalcogenide Semiconducting Layers." MRS Advances 3, no. 6-7 (2018): 351–57. http://dx.doi.org/10.1557/adv.2018.110.

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ABSTRACTIn this work, we report on the electron spin resonance (ESR) studies performed on few-layered nanocrystalline (NCs) MoS2, WS2, and TiS2 prepared using hydrothermal and vapor transport methods. From the temperature dependent ESR spectra collected from MoS2 NCs, we have identified adsorbed oxygen species, sulphur vacancies, thio- and oxo-Mo5+ related paramagnetic defect centers. WS2 NCs have exhibited W+3 and oxo-W+5 paramagnetic defect spin species. TiS2 NCs showed defects such as Fe3+ (unwanted), oxygen and sulfur vacancies. This work demonstrates the usage of spin-sensitive spectroscopy such as ESR in unravelling the defects which contain unpaired electron spin centers in layered NCs two-dimensional materials.

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Zinovieva, Aigul, Natalia Stepina, Anatoly Dvurechenskii, Leonid Kulik, Gregor Mussler, Juergen Moers, and Detlev Grützmacher. "Simultaneous Localization of Electrons in Different Δ-Valleys in Ge/Si Quantum Dot Structures." Solid State Phenomena 233-234 (July 2015): 415–18. http://dx.doi.org/10.4028/www.scientific.net/ssp.233-234.415.

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In the present work the possibility of simultaneous localization of two electrons in Δ100 and Δ001 valleys in ordered structures with Ge/Si quantum dots (QD) was verified experimentally by electron spin resonance (ESR) method. ESR spectra obtained for the ordered ten-layered QD structure in the dark shows the signal corresponding to electron localization in Si at the Ge QD base edges, in Δ100, Δ010 valleys (gzz=1.9985, gin-plane=1.999). Light illumination causes the appearance of a new ESR line (gzz=1.999) attributed to the electrons in Δ001 valley localized at the QD apexes. Observed effect is explained by enhancement of electron confienment near QD apex by Coloumb attraction to the photogenerated hole trapped in Ge QD.

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GORONCY, ALEXANDER K., HORACIO A. FARACH, CHARLES P. POOLE JR., M. FRANCISCO GONZALEZ, TOMAS DE PAOLI, and ALFREDO HAGER. "GLUTATHIONE DECAY IN STORED BLOOD MEASURED BY ELECTRON SPIN RESONANCE." Journal of Biological Systems 04, no. 01 (March 1996): 39–44. http://dx.doi.org/10.1142/s0218339096000053.

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An electron spin resonance has been developed by our group which employs spin labeled erythrocytes to study the decay of glutathione in stored blood. The results are compared with determinations made by the usual optical method. The values of the glutathione concentration C(t) in the blood fit the stretched exponential equation. [Formula: see text] where C0 is the initial concentration, at time t=0, Cf is the final concentration at time t→∞, and the constants n and τ have the average values [Formula: see text] for the ESR and optical determinations. The reproducibility is better and the scatter of the data is much less for our recently developed ESR method.

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Nakazawa, H., K. Ichimori, Y. Shinozaki, H. Okino, and S. Hori. "Is superoxide demonstration by electron-spin resonance spectroscopy really superoxide?" American Journal of Physiology-Heart and Circulatory Physiology 255, no. 1 (July 1, 1988): H213—H215. http://dx.doi.org/10.1152/ajpheart.1988.255.1.h213.

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A recent study has indicated that the generation of an oxygen radical in freeze-clamped myocardium on reperfusion can be directly demonstrated using electron-spin resonance spectroscopy (ESR). However, the results need to be analyzed with caution, since artifactual radicals are misleading problems common to this method. To test whether that reported superoxide is truly the biologically existing radical or an artifactual radical, we performed experiments using isolated, perfused rat and rabbit hearts and open-chest canine hearts subjected to ischemia/reperfusion. Radicals were freeze trapped at 77 degrees K, and ESR measurements were made. The ESR spectra exhibited four free radicals. Among these, two radicals which had been previously claimed as superoxide and a nitrogen-centered radical were shown as mechanically yielded artifactual radicals. These were produced by pulverization of the frozen sample. In artifact-free samples, superoxide could not be detected. The radicals native to the myocardium were identified as coenzyme Q10-. and another radical the species of which remains unclear.

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43

Yin, Ouyang, Yue, Wang, and Xia. "High Magnetic Field ESR in S = 1 Skew Chain Antiferromagnet Ni2V2O7 Single Crystal." Crystals 9, no. 9 (September 7, 2019): 468. http://dx.doi.org/10.3390/cryst9090468.

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We report electron spin resonance (ESR) in S = 1 skew chain antiferromagnet Ni2V2O7, which exhibits a spin-flop transition and a well-defined 1/2 magnetization plateau. The antiferromagnetic (AFM) ordering at TN = 7 K can be reflected by the temperature-dependent ESR spectra at low frequency for the easy axis. At 2 K, at the spin-flop transition fields along the easy a and b axes, anomalies are observed from the frequency‒field relationship. However, these modes cannot be understood by the conventional two-sublattice AFM resonance theory with uniaxial anisotropy. For the easy b axis, an unusual resonance mode is observed and its resonance field increases with decreasing frequency. This ESR mode becomes softening at ~8 T, corresponding to the onset of the 1/2 magnetization plateau.

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Saiz, C. L., E. Castro, L. M. Martinez, S. R. J. Hennadige, L. Echegoyen, and S. R. Singamaneni. "Electron Spin Resonance Investigations on Perovskite Solar Cell Materials Deposited on Glass Substrate." MRS Advances 3, no. 32 (2018): 1831–36. http://dx.doi.org/10.1557/adv.2018.171.

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ABSRTACTIn this article, we report low-temperature electron spin resonance (ESR) investigations carried out on solution processed three-layer inverted solar cell structures: PC61BM/CH3NH3PbI3/PEDOT:PSS/Glass, where PC61BM and PEDOT:PSS act as electron and hole transport layers, respectively. ESR measurements were conducted on ex-situ light (1 Sun) illuminated samples. We find two distinct ESR spectra. First ESR spectra resembles a typical powder pattern, associated with gx = gy = 4.2; gz = 9.2, found to be originated from Fe3+ extrinsic impurity located in the glass substrate. Second ESR spectra contains a broad (peak-to-peak line width ∼ 10 G) and intense ESR signal appearing at g = 2.008; and a weak, partly overlapped, but much narrower (peak-to-peak line width ∼ 4 G) ESR signal at g = 2.0022. Both sets of ESR spectra degrade in intensity upon light illumination. The latter two signals were found to stem from light-induced silicon dangling bonds and oxygen vacancies, respectively. Our controlled measurements confirm that these centers were generated during UV-ozone treatment of the glass substrate –a necessary step to be performed before PEDOT:PSS is spin coated. This work forms a significant step in understanding the light-induced- as well as extrinsic defects in perovskite solar cell materials.

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Oliva, Cesare, Francesco Orsini, Serena Cappelli, Paolo Arosio, Mattia Allieta, Mauro Coduri, and Marco Scavini. "Electron Spin Resonance and Atomic Force Microscopy Study on Gadolinium Doped Ceria." Journal of Spectroscopy 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/491840.

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A combined electron spin resonance (ESR) and atomic force microscopy (AFM) study on Ce1−xGdxO2−x/2samples is here presented, aimed at investigating the evolution of the ESR spectral shape as a function ofxin a wide composition range. At lowx=0.02, the spectrum is composed of features atgeff≈2; 2.8; 6. With increasingx, this pattern merges into a singlegeff≈2broad ESR curve, which assumes a Dysonian-shaped profile atx≥0.5, whereas, at thesexvalues, AFM measurements show an increasing surface roughness. It is suggested that the last could cause the formation of surface polaritons at the origin of the particular ESR spectral profile observed at these high Gd doping levels.

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KINOSHITA, N., Y. TANAKA, M. TOKUMOTO, and S. MATSUMIYA. "RELATION BETWEEN THE SUPERCONDUCTIVITY AND ELECTRON SPIN RESONANCE ON DOPED C60." International Journal of Modern Physics B 06, no. 23n24 (December 1992): 4025–29. http://dx.doi.org/10.1142/s0217979292002139.

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Superconducting transition of Cs-doped C60 is observed at about 29 K along with those of the already reported K- and Rb-doped C 60. ESR studies have been carried out on alkali-metal (K, Rb, Cs)-doped C 60 and relations between the superconductivity and the observed ESR properties are reported.

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47

Tamulienė, J., A. Tamulis, and J. Kulys. "Electronic Structure of Dodecyl Syringate Radical Suitable for ESR Molecular Quantum Computers." Nonlinear Analysis: Modelling and Control 9, no. 2 (April 25, 2004): 185–96. http://dx.doi.org/10.15388/na.2004.9.2.15166.

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The neutral radical of dodecyl syringate is suggested as a candidate for molecular Electron Spin Resonance (ESR) quantum computers. The first principle of quantum chemical calculations indicates that this molecule with a stable delocalised electron spin may represent a qubit in quantum information processing. The spin density analysis exhibits that unpaired spin of the radical is delocalised in the region of not-compensated valence bond. Isotropic Fermi contact coupling constants and anisotropic spin dipole couplings was investigated and indicated the largest hyperfine splitting (HFS) of ESR spectra on atoms of the above mentioned region of not-compensated valence bond.

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Hutton, DR, FA Darmann, and GJ Troup. "Electron Spin Resonance of V4+(VO2+) in Beryl." Australian Journal of Physics 44, no. 4 (1991): 429. http://dx.doi.org/10.1071/ph910429.

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Synthetic Australian Biron beryl coloured green by vanadium was irradiated with a dose of 10 kGy of 137Cs y rays. The reSUlting ESR spectrum has been modelled as being due to 12 equivalent V02+ centres, each arising from a complex formed from the substitution of V3+ in the beryl aluminium octahedral site, together with electron loss and motion towards a nearest neighbour oxygen. Each centre can be fitted to an axial spin Hamiltonian

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49

Holubová, Jana, Zdeněk Černošek, and Ivan Pavlík. "Electron Spin Resonance Super-Hyperfine Splitting Study of Polycrystalline Niobocene and Vanadocene Dichlorides." Collection of Czechoslovak Chemical Communications 61, no. 12 (1996): 1767–72. http://dx.doi.org/10.1135/cccc19961767.

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The electron spin resonance (ESR) spectra of niobocene and vanadocene dichlorides were studied on the title compounds prepared as magnetically diluted species in polycrystalline form. The resolved super-hyperfine splitting of anisotropic ESR spectra of both studied compounds was firstly observed. Computer simulation confirmed that this super-hyperfine splitting is due to interaction of unpaired electron with nuclear spin of two chlorine ligands. Average value of super-hyperfine coupling constant is 13.3 MHz for niobocene dichloride. For vanadocene dichloride, it is estimated to be in the range of 6-10 MHz. It corresponds approximately to 10% delocalization of metal unpaired electron spin density onto chlorine ligands in case of niobocene dichloride and to 4-7% delocalization in case of vanadocene dichloride.

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Schramm, D. U., and A. M. Rossi. "Electron spin resonance (ESR), electron nuclear double resonance (ENDOR) and general triple resonance of irradiated biocarbonates." Applied Radiation and Isotopes 47, no. 11-12 (November 1996): 1443–55. http://dx.doi.org/10.1016/s0969-8043(96)00197-2.

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Journal articles on the topic 'Electron spin resonance (ESR)'

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