On the occasion of my 85th birthday, I share insights about my life and science. This autobiography has been written in an interesting period of my life. Two years ago I formulated a new paradigm in a particular scientific discipline: spin exchange. This work has helped me to see that the paradigm formulation is an effective practical tool for increasing the effectiveness of scientific research. Today

Copper complex with 1,10-phenanthroline was synthesized by a partially modified method. This complex exhibited relatively high catalytic activity in the oxidation of cyclohexanol with tert-butyl hydroperoxide. The complex was characterized by CW EPR spectroscopy (X-band) at room temperature, and results were compared with calculations carried out by the density functional theory (DFT) method. Partial

Nuclei surrounding single electron spins are valuable resources for quantum technology. For application in this area, one is often interested in weakly coupled nuclei with coupling strength on the order of a few 10–100 kHz. In this paper, we compare methods to address single nuclear spins with this type of hyperfine coupling to a single electron spin. To achieve the required spectral resolution, we

Palladium–iron alloys produced by high-dose implantation of iron ions into epitaxial palladium films were investigated with the ferromagnetic resonance (FMR) and vibrating sample magnetometry (VSM) techniques. The samples reveal distinct multiple FMR responses depending on the dose of iron ion implantation. The post-implantation annealing at 770 K does not bring the implanted films to a homogeneous

This paper describes the design considerations for a dual mode X-band continuous wave (CW) Electron Paramagnetic Resonance (EPR) cavity, for simultaneous EPR measurement and microwave heating of the same sample. An elliptical cavity geometry is chosen to split the degeneracy of the TM110 mode, allowing for a well resolved EPR signal with the TM110,a and TM110,b modes resonating at around 10 GHz and

Poly 2-acrylamido-2-methy-1-propanesulfonic acid sodium salt and gelatin (PASSAG) gel dosimeter has a negligible toxicity and also excellent dosimetric characteristics. Nonetheless, the main drawback of this gel dosimeter is its relatively low response–dose sensitivity. In this study, we investigated whether adding glucose into the conventional PASSAG gel dosimeter could increase the response–dose

Human nails have been studied for many years for potential use for dosimetry, based on the EPR signals induced by ionizing radiation, but a fully validated protocol to measure doses retrospectively has not yet been developed. The major problem is that the EPR spectrum of irradiated nails is complex and its radiation-induced signals (RIS) overlap with an endogenous signal called the background signal

Photoinduced charge transfer processes in diastereomers are currently being intensively studied as models for the binding of chiral drugs to chiral amino acid residues located in the active centers of enzymes and receptors. In this regard, direct detection of paramagnetic forms of diastereomers formed upon UV irradiation is of considerable interest. In the present study, we use photochemically induced

The Gordon coupler was introduced for use in EPR experiments at liquid helium temperatures. It provides an evanescent wave incident on the iris of a microwave resonator. Match of power incident on the coupler to the resonator is obtained by variation of the amplitude of an evanescent wave that arises from displacement of a dielectric wedge in a tapered waveguide. Reduced microphonics from helium bubbling

The Three Sites Exchange Model (3SEM) was properly used to describe Proton (1H) Magnetic Relaxation Dispersion (1HMRD) in intracellular samples of hemoglobin A (HbA) and hemoglobin S (HbS) at 310 K. The HbA and HbS samples were obtained from whole blood of voluntary donors and patients, respectively, and processed by classical methods (centrifugation, decanting and freezing–thawing cycles). The 1HMRD

We introduce an optimized design for a three-magnet array unilateral magnetic resonance (MR) device. The sensitive spot is 0.5 cm3, and begins roughly 0.5 cm from the magnet surface with a field variation of less than 1.5% of the B0 resonant frequency. 3D simulation was used in conjunction with a trust-region optimization method to determine the optimal magnet geometry to achieve a large sensitive

In this review, we discuss the value of biological dosimetry and electron paramagnetic resonance (EPR) spectroscopy in the medical management support of acute radiation syndrome (ARS). Medical management of an ionizing radiation scenario requires significant information. For optimal medical aid, this information has to be rapidly (< 3 days) delivered to the health-care provider. Clinical symptoms may

The hydrogen bond plays a key role in weak directional intermolecular interactions. It is operative in determining molecular conformation and aggregation, and controls the function of many chemical systems, ranging from inorganic, organic to biological molecules. Although an enormous amount of spectroscopic information has been collected about hydrogen-bond formation between molecules with closed-shell

A new and robust statistical approach is explored with the objective to derive quantitative and reliable information on the molecular dynamics within distinct domains (crystalline, intermediate and amorphous domains) of ultra-high molecular weight polyethylene (UHMWPE). The method consists of a critical evaluation of the free induction decay (FID) model, which is used to generate synthetic FID with

Continuous wave and pulse X-band electron paramagnetic resonance spectroscopy are used to determine structure, magnetic and relaxation properties of paramagnetic centers formed by impurity ytterbium ions in forsterite (Mg2SiO4) single crystals. It is found that Yb3+ ions substitute Mg2+ ions both as single ions and as dimeric associates with nearby magnesium vacancy. For all ytterbium centers, magnetic

Solid-state \(^{207}\)Pb NMR spectroscopy was used to identify the pigments painted on the surface of a cultural heritage material. The \(^{207}\)Pb NMR magic-angle-spinning spectrum was measured under 18.8 T for the 1.0% lead-containing pigment sample of a historical clay doll. By comparing with the reference spectrum and NMR parameters, minium (Pb\(_3\)O\(_4\)) was determined to be used as a red

The Dobryakov–Lebedev relation (Sov Phys Doklady 13:873, 1969), which relates the line width of the first-derivative of a Gaussian–Lorentzian convolution to the line widths of its Gaussian and Lorentzian components for an unresolved EPR line, is extended to resolved lines. Applying this extension to nitroxide-free radicals in solutions of low-viscosity solvents offers an opportunity to study interactions

For billions of years, nature has optimized the photosynthetic machinery that converts light energy into chemical energy. Key primary reactions of photosynthesis occur in large membrane protein–cofactor complexes. The light-induced sequential electron transfer reactions occur through a chain of donor/acceptor cofactors embedded in the protein matrix resulting in a long-lived transmembrane charge-separated

Nitroxide probes have been commonly used for biomedical EPR imaging applications; however, image quality has been limited by the number of image projections, as well as the probe linewidth and hyperfine structure. In the current study, we evaluate the use of fast millisecond scan EPR projection acquisition along with a novel reconstruction algorithm optimized for 3D spatial EPR image reconstruction

The kinetics of the transfer of the chelate, ethylenediamine tetraacetate (EDTA), from Calcium(II) to Copper(II) in imidazole (Im) buffers near neutral pH, corresponding to the conversion, [Cu(II)Im4]2+→ [Cu(II)EDTA]2−, are characterized with stopped-flow absorption spectroscopy and implemented as a tool for calibrating the interval between mixing and freezing, the freeze-quench time (tQ), of a rapid

Nitroxide spin probes and spin labels are broadly utilized in EPR oximetry studies ranging from in vivo investigation to profiling heterogeneous environment of lipid bilayer membranes and proteins by site-specific oxygen-accessibility experiments. In such experiments, effective collision distances of the spin exchange interaction between the nitroxide and molecular oxygen are typically assumed to be

The utility for electron paramagentic resonance (EPR or ESR)-based radiation biodosimetry has received increasing recognition concerning its potential to assist in guiding the clinical management of medical countermeasures in individuals unwantedly exposed to injurious levels of ionizing radiation. Similar to any of the standard physical dosimetric methods currently employed for screening clinically

The feasibility of one-dimensional two-pulse correlation spectroscopy (COSY) Electron Paramagnetic Resonance (EPR) sequence for distance measurements in biological systems using nitroxide biradicals is investigated numerically at Ku-band. It is found that the COSY sequences can be exploited to measure distances between the two nitroxides in the range \(17.3 \AA \lesssim r \lesssim 47.0 \AA (0.5 \mathrm{MHz}\le

Relaxation enhanced angiography without contrast and triggering (REACT) is a non-contrast-enhanced angiography technique that highlights blood and suppresses the low T2 and T1 background tissues by using a combination of T2prep and inversion modules, respectively. In this work, the T2prep module is modified to effectively perform both T2prep and inversion. This eliminates the need for a separate inversion

This work is focused on the effects of drying/re-saturation cycles on the structure and components of White Portland Cement (WPC) samples. In particular, WPC of 0.5 water-to-cement ratio was studied by 1H Nuclear Magnetic Resonance (NMR) Relaxometry. A number of NMR sequences and different data processing methods were applied. Short (14 days of re-saturation) and long (6 months for the whole cycle)

Self-aggregation of amyloid proteins is a crucial step in neurodegenerative disease. The protein alpha-synuclein (αS) is implicated in Parkinson’s disease. In an extension of the demonstration of in situ observation of intermediates in αS-aggregation by continuous wave (cw) EPR at room temperature (Zurlo et al. PLoS One 16: e0245548, 2021) by spin-label EPR, here the spin label is attached to position

Five types of radicals were considered in order to describe the experimental EPR spectra of polycrystalline calcium gluconate irradiated with gamma quanta. This set made it possible to correctly describe the X- and Q-band EPR spectra of CaGluc2·H2O with one set of anisotropic parameters HFI and g-factors. Because it is assumed that irradiation with gamma quanta leads to the rupture of the C-H bond;

The experimental realization of the two-frequency 14N nuclear quadrupole resonance (NQR) technique with use of the gradiometer radiofrequency (RF) probe for applications in the remote detection of explosives and other substances has been proposed. The planar two-frequency gradiometer has been designed, modeled and manufactured. The regions, where the RF magnetic fields are nearly orthogonal to each

Dynamics of spin dimers in multiple quantum NMR experiment is studied on the 5-qubit superconducting quantum processor of IBM Quantum Experience for the both pure ground and thermodynamic equilibrium (mixed) initial states. The work can be considered as a first step towards an application of quantum computers to solving problems of magnetic resonance. This article is dedicated to Prof. Klaus Möbius

Magnetic resonance imaging (MRI) system is used as one of the most common methods to read out the response of polymer gel dosimeters. The imaging protocols can have a remarkable effect on the response of polymer gel dosimeters; hence, the impact of imaging parameters on the response of each type of polymer gel dosimeter should be addressed. This study aims to investigate the effect of MRI parameters

Due to fast relaxation processes of transition metal ions, electron paramagnetic resonance (EPR) spectroscopy of metalloproteins needs to be performed at cryogenic temperatures. To avoid damaging the biological system upon freezing, a cryoprotectant is generally added to the sample as a glassing agent. Even though cryoprotectants are expected to be inert substances, evidences in literature show their