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RADIOLOGY AND NUCLEAR MEDICINE (191 journals)                     

Showing 1 - 191 of 191 Journals sorted alphabetically
Abdominal Radiology     Hybrid Journal   (Followers: 21)
Academic Radiology     Hybrid Journal   (Followers: 27)
Acta Cytologica     Hybrid Journal   (Followers: 3)
Acta Radiologica     Hybrid Journal   (Followers: 2)
Acta Radiologica Open     Open Access   (Followers: 3)
Acta Radiológica Portuguesa     Open Access  
Advanced Structural and Chemical Imaging     Open Access   (Followers: 2)
Advances in Computed Tomography     Open Access   (Followers: 3)
Advances in Radiation Oncology     Open Access   (Followers: 3)
AINS - Anasthesiologie - Intensivmedizin - Notfallmedizin - Schmerztherapie     Hybrid Journal   (Followers: 5)
Alasbimn Journal     Open Access   (Followers: 2)
American Journal of Neuroradiology     Full-text available via subscription   (Followers: 20)
American Journal of Roentgenology     Full-text available via subscription   (Followers: 34)
Annals of Nuclear Medicine     Hybrid Journal   (Followers: 4)
Annals of the ICRP     Hybrid Journal   (Followers: 4)
Applied In Vitro Toxicology     Hybrid Journal   (Followers: 2)
Applied Radiology     Full-text available via subscription   (Followers: 10)
Arab Journal of Interventional Radiology     Open Access   (Followers: 1)
Asia Oceania Journal of Nuclear Medicine & Biology     Open Access   (Followers: 3)
Bangladesh Journal of Nuclear Medicine     Open Access  
Belgian Journal of Radiology     Open Access   (Followers: 3)
Biomedical Imaging and Intervention Journal     Open Access   (Followers: 4)
BJR     Hybrid Journal   (Followers: 21)
BJR | case reports     Open Access   (Followers: 6)
BMC Medical Imaging     Open Access   (Followers: 10)
Canadian Association of Radiologists Journal     Full-text available via subscription   (Followers: 2)
Cancer Biotherapy & Radiopharmaceuticals     Hybrid Journal   (Followers: 1)
Cancer Radiothérapie     Full-text available via subscription   (Followers: 1)
Case Reports in Radiology     Open Access   (Followers: 12)
Chinese Journal of Academic Radiology     Hybrid Journal  
Clinical and Translational Imaging     Hybrid Journal   (Followers: 1)
Clinical and Translational Radiation Oncology     Open Access   (Followers: 1)
Clinical Imaging     Hybrid Journal   (Followers: 5)
Clinical Mass Spectrometry     Open Access  
Clinical Neuroradiology     Hybrid Journal   (Followers: 3)
Clinical Nuclear Medicine     Hybrid Journal   (Followers: 2)
Clinical Radiology     Hybrid Journal   (Followers: 18)
Computerized Medical Imaging and Graphics     Hybrid Journal   (Followers: 14)
Concepts in Magnetic Resonance Part A     Open Access   (Followers: 1)
Concepts in Magnetic Resonance Part B, Magnetic Resonance Engineering     Open Access   (Followers: 1)
Concussion     Open Access  
Contemporary Diagnostic Radiology     Full-text available via subscription   (Followers: 3)
Contrast Media & Molecular Imaging     Open Access   (Followers: 2)
Critical Ultrasound Journal     Open Access   (Followers: 3)
Current Medical Imaging Reviews     Hybrid Journal   (Followers: 3)
Current Problems in Diagnostic Radiology     Hybrid Journal   (Followers: 10)
Current Radiology Reports     Hybrid Journal   (Followers: 4)
Dentomaxillofacial Radiology     Hybrid Journal   (Followers: 4)
Der Nuklearmediziner     Hybrid Journal  
Der Radiologe     Hybrid Journal   (Followers: 1)
Diagnostic and Interventional Radiology     Open Access   (Followers: 6)
Digestive Disease Interventions     Hybrid Journal  
DNA and RNA Nanotechnology     Open Access   (Followers: 6)
Egyptian Journal of Radiology and Nuclear Medicine     Open Access   (Followers: 1)
EJNMMI Radiopharmacy and Chemistry     Open Access  
Emergency Radiology     Hybrid Journal   (Followers: 8)
Endoscopic Ultrasound     Open Access  
European Journal of Nanomedicine     Hybrid Journal   (Followers: 1)
European Journal of Nuclear Medicine and Molecular Imaging     Hybrid Journal   (Followers: 12)
European Journal of Radiology     Hybrid Journal   (Followers: 21)
European Journal of Radiology Open     Open Access   (Followers: 9)
European Radiology     Hybrid Journal   (Followers: 17)
European Radiology Experimental     Open Access  
European Radiology Supplements     Hybrid Journal   (Followers: 3)
Feuillets de Radiologie     Full-text available via subscription  
Frontiers in Neurogenesis     Open Access   (Followers: 2)
IEEE Transactions on Medical Imaging     Hybrid Journal   (Followers: 28)
IEEE Transactions on Radiation and Plasma Medical Sciences     Hybrid Journal   (Followers: 1)
Imagen Diagnóstica     Full-text available via subscription  
Imaging Decisions MRI     Hybrid Journal   (Followers: 2)
Indian Journal of Nuclear Medicine     Open Access   (Followers: 2)
Indian Journal of Radiology and Imaging     Open Access   (Followers: 4)
Insights into Imaging     Open Access   (Followers: 4)
International Journal of Biomedical Nanoscience and Nanotechnology     Hybrid Journal   (Followers: 8)
International Journal of Computer Assisted Radiology and Surgery     Hybrid Journal   (Followers: 6)
International Journal of Medical Physics, Clinical Engineering and Radiation Oncology     Open Access   (Followers: 10)
International Journal of Nanomedicine     Open Access   (Followers: 2)
International Journal of Radiation Biology     Hybrid Journal   (Followers: 6)
International Journal of Tomography & Simulation     Full-text available via subscription   (Followers: 1)
Interventional Neuroradiology     Hybrid Journal   (Followers: 1)
Interventionelle Radiologie Scan     Hybrid Journal   (Followers: 1)
Investigative Radiology     Hybrid Journal   (Followers: 10)
Iranian Journal of Medical Physics     Open Access  
Iranian Journal of Nuclear Medicine     Open Access   (Followers: 1)
Iranian Journal of Radiology     Open Access   (Followers: 5)
Japanese Journal of Radiology     Hybrid Journal   (Followers: 4)
Journal de Radiologie     Full-text available via subscription  
Journal de Radiologie Diagnostique et Interventionnelle     Full-text available via subscription   (Followers: 2)
Journal of Nanomedicine & Nanotechnology     Open Access   (Followers: 1)
Journal of Clinical Imaging Science     Open Access   (Followers: 3)
Journal of Clinical Interventional Radiology ISVIR     Open Access   (Followers: 2)
Journal of Clinical Ultrasound     Hybrid Journal   (Followers: 6)
Journal of Computer Assisted Tomography     Hybrid Journal   (Followers: 1)
Journal of Diagnostic Medical Sonography     Hybrid Journal  
Journal of Diagnostic Radiography and Imaging     Hybrid Journal   (Followers: 4)
Journal of Fetal Medicine     Hybrid Journal  
Journal of Global Radiology     Open Access   (Followers: 2)
Journal of Indian Academy of Oral Medicine and Radiology     Open Access   (Followers: 3)
Journal of Innovative Optical Health Sciences     Open Access  
Journal of Liver : Disease & Transplantation     Hybrid Journal   (Followers: 7)
Journal of Magnetic Resonance     Hybrid Journal   (Followers: 14)
Journal of Magnetic Resonance Imaging     Hybrid Journal   (Followers: 17)
Journal of Medical Imaging     Free   (Followers: 5)
Journal of Medical Imaging and Radiation Oncology     Hybrid Journal   (Followers: 3)
Journal of Medical Imaging and Radiation Sciences     Hybrid Journal   (Followers: 5)
Journal of Medical Radiation Sciences     Open Access   (Followers: 3)
Journal of Neuroradiology     Full-text available via subscription   (Followers: 4)
Journal of Nuclear Medicine     Full-text available via subscription   (Followers: 20)
Journal of Nuclear Medicine & Radiation Therapy     Open Access   (Followers: 3)
Journal of Nucleic Acids Investigation     Open Access   (Followers: 2)
Journal of Oral and Maxillofacial Radiology     Open Access   (Followers: 1)
Journal of Pediatric Neuroradiology     Hybrid Journal   (Followers: 3)
Journal of Radiation and Cancer Research     Open Access  
Journal of Radiation Research     Open Access   (Followers: 3)
Journal of Radiation Research and Applied Sciences     Open Access   (Followers: 2)
Journal of Radiobiology     Open Access   (Followers: 1)
Journal of Radiological Protection     Full-text available via subscription   (Followers: 4)
Journal of Radiology and Oncology     Open Access  
Journal of Radiology Nursing     Hybrid Journal   (Followers: 2)
Journal of Radiosurgery     Hybrid Journal   (Followers: 2)
Journal of Radiotherapy in Practice     Hybrid Journal   (Followers: 7)
Journal of the American College of Radiology     Hybrid Journal   (Followers: 10)
Journal of Thoracic Imaging     Hybrid Journal   (Followers: 3)
Journal of Vascular and Interventional Radiology     Hybrid Journal   (Followers: 13)
La radiologia medica     Hybrid Journal  
Magnetic Resonance Imaging     Hybrid Journal   (Followers: 7)
Magnetic Resonance Imaging Clinics of North America     Full-text available via subscription   (Followers: 8)
Magnetic Resonance in Medicine     Hybrid Journal   (Followers: 16)
Medical Image Analysis     Hybrid Journal   (Followers: 15)
Medical Imaging and Radiology     Open Access   (Followers: 7)
Nepalese Journal of Radiology     Open Access   (Followers: 1)
Neurographics     Free   (Followers: 3)
NeuroImage : Clinical     Open Access   (Followers: 15)
Neuroradiology     Hybrid Journal   (Followers: 9)
Neuroradiology Journal The     Hybrid Journal   (Followers: 1)
Nuclear Medicine and Biology     Hybrid Journal   (Followers: 4)
Nuclear Medicine and Molecular Imaging     Hybrid Journal   (Followers: 4)
Nuclear Medicine Communications     Hybrid Journal   (Followers: 2)
Nuclear Medicine Review     Open Access   (Followers: 2)
Nuklearmedizin / NuclearMedicine     Hybrid Journal  
Open Journal of Clinical Diagnostics     Open Access   (Followers: 1)
Open Journal of Medical Imaging     Open Access   (Followers: 1)
Open Journal of Radiology     Open Access   (Followers: 4)
Open Medical Imaging Journal     Open Access  
Oral Radiology     Hybrid Journal   (Followers: 1)
Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology     Full-text available via subscription   (Followers: 9)
Pediatric Radiology     Hybrid Journal   (Followers: 6)
Physica Medica     Full-text available via subscription   (Followers: 3)
Progress in Nuclear Magnetic Resonance Spectroscopy     Full-text available via subscription   (Followers: 8)
Radiation Protection and Environment     Open Access   (Followers: 1)
Radiatsionnaya Gygiena = Radiation Hygiene     Open Access  
Radiographics     Full-text available via subscription   (Followers: 27)
Radiography     Full-text available via subscription   (Followers: 7)
Radiography Open     Open Access   (Followers: 1)
Radiología     Full-text available via subscription   (Followers: 1)
Radiología (English Edition)     Full-text available via subscription  
Radiologia Brasileira     Open Access  
Radiologic Clinics of North America     Full-text available via subscription   (Followers: 19)
Radiologie up2date     Hybrid Journal   (Followers: 1)
Radiology     Full-text available via subscription   (Followers: 41)
Radiology Case Reports     Open Access   (Followers: 2)
Radiology of Infectious Diseases     Open Access   (Followers: 3)
Radiology Research and Practice     Open Access   (Followers: 3)
Radiopraxis     Hybrid Journal  
Reports in Medical Imaging     Open Access  
Research and Reports in Nuclear Medicine     Open Access   (Followers: 1)
Research Journal of Radiology     Open Access   (Followers: 5)
Revista Argentina de Radiología / Argentinian Journal of Radiology     Open Access  
Revista Chilena de Radiologia     Open Access  
Revista Española de Medicina Nuclear e Imagen Molecular     Full-text available via subscription   (Followers: 2)
Revista Española de Medicina Nuclear e Imagen Molecular (English Edition)     Full-text available via subscription  
Revista Internacional de Ciencias Podológicas     Open Access  
Seminars in Interventional Radiology     Hybrid Journal   (Followers: 6)
Seminars in Musculoskeletal Radiology     Hybrid Journal   (Followers: 6)
Seminars in Nuclear Medicine     Hybrid Journal   (Followers: 5)
Seminars in Roentgenology     Hybrid Journal   (Followers: 3)
Seminars in Ultrasound, CT and MRI     Hybrid Journal   (Followers: 9)
Shadows : The New Zealand Journal of Medical Radiation Technology     Full-text available via subscription   (Followers: 2)
Skeletal Radiology     Hybrid Journal   (Followers: 10)
Solid State Nuclear Magnetic Resonance     Hybrid Journal   (Followers: 3)
South African Journal of Radiology     Open Access   (Followers: 1)
South African Radiographer     Full-text available via subscription  
Sri Lanka Journal of Radiology     Open Access  
Surgical and Radiologic Anatomy     Hybrid Journal   (Followers: 6)
Techniques in Vascular and Interventional Radiology     Full-text available via subscription   (Followers: 8)
Topics in Magnetic Resonance Imaging     Hybrid Journal   (Followers: 3)
Ultraschall in der Medizin - European Journal of Ultrasound     Hybrid Journal   (Followers: 2)
Ultrasonic Imaging     Hybrid Journal   (Followers: 2)
Ultrasound Quarterly     Hybrid Journal   (Followers: 2)
West African Journal of Radiology     Open Access   (Followers: 1)
World Journal of Nuclear Medicine     Open Access   (Followers: 2)

           

Similar Journals
Journal Cover
Solid State Nuclear Magnetic Resonance
Journal Prestige (SJR): 1.068
Citation Impact (citeScore): 2
Number of Followers: 3  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0926-2040 - ISSN (Online) 1527-3326
Published by Elsevier Homepage  [3206 journals]
  • Sensitivity Enhancement in 2D Double Cross Polarization Experiments under
           fast MAS by Recycling Unused Protons
    • Abstract: Publication date: Available online 13 February 2020Source: Solid State Nuclear Magnetic ResonanceAuthor(s): S. Jayanthi, A. Lupulescu We demonstrate sensitivity enhancement via recycling of proton magnetization in 2D Double Cross Polarization (Double CP) experiments performed on fully protonated and uniformly labeled (13C, 15N) samples at a magic angle spinning rate of 60 kHz. Unused proton magnetization is preserved during t1 evolution either by locking it with CW irradiation or by employing rotor-synchronized pi pulses. A flip-back pulse together with a modified second CP block preserves unused proton magnetization resulting in enhanced sensitivity. We have achieved sensitivity enhancements of 15-20% and 25-28% in 1H-13C and 1H-15N 2D Double CP experiments respectively. At shorter recycle delays (∼0.25T1), relative sensitivity enhancements of 40-45% and 55% were obtained in 1H-13C and 1H-15N 2D Double CP experiments respectively. An analysis of the sensitivity enhancements and theoretical estimation of lineshapes in indirect dimension in the presence of proton recycling is provided.Graphical abstractImage 1
       
  • Selective detection of active pharmaceutical ingredients in tablet
           formulations using solid-state NMR spectroscopy
    • Abstract: Publication date: Available online 28 January 2020Source: Solid State Nuclear Magnetic ResonanceAuthor(s): You-lee Hong, G.N. Manjunatha Reddy, Yusuke Nishiyama Atomic-level characterization of active pharmaceutical ingredients (API) is crucial in pharmaceutical industry because APIs play an important role in physicochemical properties of drug formulations. However, the analysis of targeted APIs in intact tablet formulations is less straightforward due to the coexistence of excipients as major components and different APIs at dilute concentrations (often below 10 wt% loading). Although solid-state (ss) NMR spectroscopy is widely used to investigate short-range order, polymorphism, and pseudo-polymorphism in neat pharmaceutical compounds, the analysis of complex drug formulations is often limited by overlapped signals that originate from structurally different APIs and excipients. In particular, such examples are frequently encountered in the analysis of 1H ssNMR spectra of pharmaceutical formulations. While the high-resolution in 1H ssNMR spectra can be attained by, for example, high magnetic fields accompanied by fast magic-angle spinning (MAS) approaches, the spectral complexity associated with the mixtures of compounds hinders the accurate determination of chemical shifts and through-space proximities. Here we propose a fast MAS (70 kHz) NMR experiment for the selective detection of 1H signals associated with an API from a severely overlapped NMR spectrum of a tablet formulation. Spectral simplification is achieved by combining (i) symmetry-based dipolar recoupling (SR412) rotational-echo saturation-pulse double-resonance (RESPDOR) with the phase-modulate (PM) saturation pulses, (ii) radio frequency-driven recoupling (RFDR), and (iii) double-quantum excitation using Back-to-Back (BaBa) pulse sequence elements. First, 1H sites in close proximities to 14N nuclei of an API are excited using a PM-S-RESPDOR sequence, and simultaneously, the other unwanted 1H signals of excipients are suppressed. Then, 1H magnetization transfer to adjacent 1H sites in the API is achieved by spin diffusion process using an RFDR sequence, which polarizes to 1H sites within the crystalline API regions of the drug formulation. Next, a PM-S-RESPDOR-RFDR sequence is combined with a Back-to-Back (BaBa) sequence to elucidate local-structures and 1H-1H proximities of the API in a dosage form. The PM-S-RESPDOR-RFDR-BaBa experiment is employed in one- (1D) and two-dimensional (2D) versions to selectively detect the 1H ssNMR spectrum of L-cysteine (10.6 wt% or 0.1 mg) in a commercial formulation, and compared with the spectra of neat L-cysteine recorded using a standard BaBa experiment. The 1H 2D double-quantum−single-quantum (DQ-SQ) spectrum of the API (L-cysteine)-detected pharmaceutical tablet is in good agreement with the 2D DQ-SQ spectrum obtained from the pure API molecule. Furthermore, the sensitivity and robustness of the experiment is examined by selectively detecting 1H{14N} signals in an amino acid salt, L-histidine.H2O.HCl.Graphical abstractImage 1
       
  • Multinuclear Solid-State NMR of Complex Nitrogen-Rich Polymeric
           Microcapsules: Weight Fractions, Spectral Editing, Component Mixing, and
           Persistent Radicals
    • Abstract: Publication date: Available online 25 January 2020Source: Solid State Nuclear Magnetic ResonanceAuthor(s): Shichen Yuan, Pu Duan, Damien L. Berthier, Géraldine León, Horst Sommer, Jean-Yves de Saint-Laumer, Klaus Schmidt-Rohr The molecular structure of a crosslinked nitrogen-rich resin made from melamine, urea, and aldehydes, and of microcapsules made from the reactive resin with multiple polymeric components in aqueous dispersion, has been analyzed by 13C, 13C{1H}, 1H-13C, 1H, 13C{14N}, and 15N solid-state NMR without isotopic enrichment. Quantitative 13C NMR spectra of the microcapsules and three precursor materials enable determination of the fractions of different components. Spectral editing of non-protonated carbons by recoupled dipolar dephasing, of CH by dipolar DEPT, and of C-N by 13C{14N} SPIDER resolves peak overlap and helps with peak assignment. It reveals that the N- and O-rich resin “imitates” the spectrum of polysaccharides such as chitin, cellulose, or Ambergum to an astonishing degree. 15N NMR can distinguish melamine from urea and guanazole, NC=O from COO, and primary from secondary amines. Such a comprehensive and quantitative analysis enables prediction of the elemental composition of the resin, to be compared with combustion analysis for validation. It also provides a reliable reference for iterative simulations of 13C NMR spectra from structural models. The conversion from quantitative NMR peak areas of structural components to the weight fractions of interest in industrial practice is derived and demonstrated. Upon microcapsule formation, 15N and 13C NMR consistently show loss of urea and aldehyde and an increase in primary amines while melamine is retained. NMR also made unexpected findings, such as imbedded crystallites in one of the resins, as well as persistent radicals in the microcapsules. The crystallites produce distinct sharp lines and are distinguished from liquid-like components by their strong dipolar couplings, resulting in fast dipolar dephasing. Fast 1H spin–lattice relaxation on the 35-ms time scale and characteristically non-exponential 13C spin–lattice relaxation indicate persistent radicals, confirmed by EPR. Through 1H spin diffusion, the mixing of components on the 2-nm scale was documented.Graphical abstractImage 1
       
  • Outside Front Cover
    • Abstract: Publication date: February 2020Source: Solid State Nuclear Magnetic Resonance, Volume 105Author(s):
       
  • Advances in studying protein disorder with solid-state NMR
    • Abstract: Publication date: Available online 12 January 2020Source: Solid State Nuclear Magnetic ResonanceAuthor(s): Ansgar B. Siemer Solution NMR is a key tool to study intrinsically disordered proteins (IDPs), whose importance for biological function is widely accepted. However, disordered proteins are not limited to solution and are also found in non-soluble systems such as fibrils and membrane proteins. In this Trends article, I will discuss how solid-state NMR can be used to study disorder in non-soluble proteins. Techniques based on dipolar couplings can study static protein disorder which either occurs naturally as e.g. in spider silk or can be induced by freeze trapping IDPs or unfolded proteins. In this case, structural ensembles are directly reflected by a static distribution of dihedral angels that can be determined by the distribution of chemical shifts or other methods. Techniques based on J-coupling can detect dynamic protein disorder under MAS. In this case, only average chemical shifts are measured but disorder can be characterized with a variety of data including secondary chemical shifts, relaxation rates, paramagnetic relaxation enhancements, or residual dipolar couplings. I describe both technical aspects and examples of solid-state NMR on protein disorder and end the article with a discussion of challenges and opportunities of this emerging field.Graphical abstractImage 1
       
  • Fast understanding of phases and phase separation in liquid crystal drug
           delivery systems using deuterium solid-state NMR
    • Abstract: Publication date: Available online 11 January 2020Source: Solid State Nuclear Magnetic ResonanceAuthor(s): Anuji Abraham, Eric Chan, Hyunsoo Park Characterization of lipid based (SPC/GDO/H2O) liquid crystal (LC) drug delivery system is non-trivial and highly complex, especially when multiple and intermediate phases are present. The phase behavior of such mixtures during hydration or delivery is still poorly understood and therefore, characterizing these systems is crucially important towards controlling their function and enhancing the understanding of their drug release behavior. Current work has established an easy way to identify liquid crystal phases and phase mixtures using deuterium (2H) solid-state nuclear magnetic (NMR) spectroscopy under static conditions without disrupting phases and with magic-angle spinning (MAS). Small angle X-ray scattering (SAXS) technique and optical microscopy were also employed to corroborate the study.Graphical abstractImage 1
       
  • CP MAS kinetics in soft matter: Spin diffusion, local disorder and thermal
           equilibration in poly(2-hydroxyethyl methacrylate)
    • Abstract: Publication date: February 2020Source: Solid State Nuclear Magnetic Resonance, Volume 105Author(s): Laurynas Dagys, Vaidas Klimkevičius, Vytautas Klimavicius, Kęstutis Aidas, Ričardas Makuška, Vytautas Balevicius The 1H–13C cross-polarization magic angle spinning kinetics was studied in poly(2-hydroxyethyl methacrylate) (pHEMA), i.e. a soft material with high degrees of internal freedom and molecular disorder, having the purpose to track the influence of increasing local incoherent contributions to the effects of coherent nature in the open quantum spin systems. The experimental CP MAS kinetic curves were analyzed in the frame of the models of isotropic and anisotropic spin diffusion with thermal equilibration. The rates of spin diffusion and spin-lattice relaxation as well as the profiles of distribution of dipolar coupling, the parameters accounting the effective size of spin clusters and the local order parameters were determined. The intensities of the peaks of periodic quasi-equilibrium origin gradually decrease with increasing disorder, i.e. going from most ordered to more disordered sites in the polymer. Assuming that the thermal motion induced by the temperature gradients is much faster than the equilibration driven by spin diffusion due the difference in spin temperatures, it was deduced that the thermal equilibration in pHEMA occurs in the time scale of 10−4 s. This is one order of magnitude faster than the spectral spin diffusion, which occurs between spins having different resonance frequencies. The thermal equilibration in the case of remote spin clusters was described by the ‘stretched exponent’ decay. This led to the fractal dimension Dp ≈ 1.65 for both carbon sites (quaternary and carbonyl). The obtained Dp value corresponds to the aggregates, which images are very similar to those for pHEMA and some other related polymer structures are usually conceived.Graphical abstractImage 1
       
  • Corrigendum to “Solid state NMR service across the world” [Solid State
           Nucl. Magn. Reson. 105 (2020) 101626]
    • Abstract: Publication date: Available online 11 December 2019Source: Solid State Nuclear Magnetic ResonanceAuthor(s): Nathan S. Barrow, Paul Jonsen
       
  • On the magnetic field stability of cryogen-free magnets for magnetic
           resonance applications
    • Abstract: Publication date: Available online 30 November 2019Source: Solid State Nuclear Magnetic ResonanceAuthor(s): Eugeny Kryukov, Angel Joaquin Perez Linde, Seema Raghunathan, Stephen Burgess, Paul Jonsen, Jeremy Good The temporal magnetic field variation associated with Cold Head operation in cryogen-free magnets was studied. Three different mechanisms for such variations were tested separately and rated by their importance. It was found that mechanical displacement of the magnet inside the cryostat is the main issue of magnetic field perturbation. In a cryostat with the Gifford- McMahon type of cryocooler, motion of the displacer with magnetic material inside also produces significant field modulation. The temperature variation of the magnet, although noticeable, leads to smaller field distortions compared to the previous two factors. It was shown that the temporal magnetic field variation could be reduced down to below 20 ppb level that could be acceptable for MRI and MAS NMR applications. It was also shown that a single cryogen-free magnet could be easily used at different fields on a day-to-day basis without compromising the field stability unlike magnets housed in a liquid helium reservoir.Graphical abstractImage 1
       
  • 31P MAS NMR and DFT study of crystalline phosphate matrices
    • Abstract: Publication date: Available online 21 November 2019Source: Solid State Nuclear Magnetic ResonanceAuthor(s): Laura Martel, Attila Kovács, Karin Popa, Damien Bregiroux, Thibault Charpentier We present the study of the phosphorus local environment by using 31P MAS NMR in a series of seven double monophosphates MIIMIV(PO4)2 (MII and MIV being divalent and tetravalent cations, respectively) of yavapaiite and low-yavapaiite type crystal structures. Solid-state and cluster DFT calculations were found to be efficient for predicting the 31P isotropic chemical shift and chemical shift anisotropy. To achieve this performance, however, a proper computational optimisation of the experimental structural data was required. From the three optimisation methods tested, the full optimisation provided the best reference structure for the calculation of the NMR parameters of the studied phosphates. Also, a better prediction of the chemical shifts was possible by using a correction to the GIPAW calculated shielding.Graphical abstractImage 1
       
  • Crystallinity of polyolefines with large side groups by low-field 1H NMR
           T 2 relaxometry: Isotactic Polybutene-1 with form II and I crystals
    • Abstract: Publication date: Available online 18 November 2019Source: Solid State Nuclear Magnetic ResonanceAuthor(s): Yanan Qin, Yongna Qiao, Walter Chassé, Victor Litvinov, Yongfeng Men Phase composition and molecular mobility were studied using 1H NMR T2 relaxometry in isotactic polybutene-1 (iPB-1) with two polymorphs - form I and II crystals. Several types of NMR relaxation methods and data analysis were evaluated for determining the most reliable way for studying physical phases in iPB-1. Three phase model provided the most appropriate description of the phase composition in iPB-1, i.e., a crystal-amorphous interface separates the crystalline and the amorphous phases. Due to complex molecular mobility in iPB-1, the amount of rigid fraction should be considered as NMR crystallinity number. Two types of chain segments are present in the amorphous phase: (1) chain segments with anisotropic mobility due to chain anchoring to crystals and chain entanglements, and (2) highly mobile chain end segments. The polymorphic phase II to I transition causes significant immobilization of polymer chains in the crystalline and the amorphous phases. Molecular weight of iPB-1 largely influences phase composition and molecular mobility in crystalline and amorphous phases.Graphical abstractImage 1
       
  • Suppressing 1H spin diffusion in fast MAS proton detected heteronuclear
           correlation solid-state NMR experiments
    • Abstract: Publication date: Available online 13 November 2019Source: Solid State Nuclear Magnetic ResonanceAuthor(s): Amrit Venkatesh, Ivan Hung, Kasuni C. Boteju, Aaron D. Sadow, Peter L. Gor'kov, Zhehong Gan, Aaron J. Rossini Fast magic angle spinning (MAS) and indirect detection by high gyromagnetic ratio (γ) nuclei such as proton or fluorine are increasingly utilized to obtain 2D heteronuclear correlation (HETCOR) solid-state NMR spectra of spin-1/2 nuclei by using cross polarization (CP) for coherence transfer. However, one major drawback of CP HETCOR pulse sequences is that 1H spin diffusion during the back X→1H CP transfer step results in relayed correlations. This problem is particularly pronounced for the indirect detection of very low-γ nuclei such as 89Y, 103Rh, 109Ag and 183W where long contact times on the order of 10–30 ms are necessary for optimal CP transfer. Here we propose two methods that eliminate relayed correlations and allow more reliable distance information to be obtained from 2D HETCOR NMR spectra. The first method uses Lee-Goldburg (LG) CP during the X→1H back-transfer step to suppress 1H spin diffusion. We determine LG conditions compatible with fast MAS frequencies (νrot) of 40–95 kHz and show that 1H spin diffusion can be efficiently suppressed at low effective radiofrequency (RF) fields (ν1,eff ≪ 0.5νrot) and also at high effective RF fields (ν1,eff ≫ 2νrot). We describe modified Hartmann-Hahn LG-CP match conditions compatible with fast MAS and suitable for indirect detection of moderate-γ nuclei such as 13C, and low-γ nuclei such as 89Y. The second method uses D-RINEPT (dipolar refocused insensitive nuclei enhanced by polarization transfer) during the X→1H back-transfer step of the HETCOR pulse sequence. The effectiveness of these methods for acquiring HETCOR spectra with reduced relayed signal intensities is demonstrated with 1H{13C} HETCOR NMR experiments on l-histidine•HCl•H2O and 1H{89Y} HETCOR NMR experiments on an organometallic yttrium complex.Graphical abstractImage 1
       
  • Solid state NMR service across the world
    • Abstract: Publication date: Available online 9 November 2019Source: Solid State Nuclear Magnetic ResonanceAuthor(s): Nathan S. Barrow, Paul Jonsen In 2013 the EPSRC published a report on the NMR equipment base serving the physical and life sciences community in the UK. Whilst this included both solution and solid state NMR, the report omitted equipment from industry or outside of the UK. This report originated as a means of benchmarking industrial solid state NMR facilities around the world. A survey of 24 SSNMR laboratories was conducted in the first half of 2019, primarily by face-to-face interviews or via telephone. Aggregated statistics relating to service throughput, equipment, and staff are presented, along with discussions about barriers to accessing SSNMR. We found that the hardware profile seen in the earlier UK-only report was representative of the worldwide view, and that the main barrier to access was a lack of knowledge about what SSNMR can do. Publishing this survey provides a strong benchmark for SSNMR laboratories, which will hopefully allow them to identify barriers that might be preventing them from performing to their optimal level in solving materials science problems.Graphical abstractImage 1
       
  • Location of paramagnetic defects in detonation nanodiamond from proton
           spin-lattice relaxation data
    • Abstract: Publication date: Available online 31 October 2019Source: Solid State Nuclear Magnetic ResonanceAuthor(s): A.M. Panich, N.A. Sergeev, S.D. Goren We developed an approach for determining location of intrinsic paramagnetic defects in nanodiamonds from the data of proton spin-lattice relaxation of the surface hydrogen atoms. The approach was applied to the detonation nanodiamond (DND) of the diameter of 5 nm. We found that dangling bonds with unpaired electron spins are located within the near-surface belt at the distance of 0.3–0.9 nm from the DND surface. The NMR data are compared with the results of EPR measurements.
       
 
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