Correction of main and transmit magnetic field (B0 and B1) inhomogeneity effects in multicomponent-driven equilibrium single-pulse observation of T1 and T2.
Research
RF Safe Research Library
Jan 1, 2011
This methods paper addresses how B0 (main field) and B1 (transmit field) inhomogeneities can bias SPGR and bSSFP steady-state MRI signals used for multicomponent T1/T2 relaxometry and myelin water analysis. It describes using DESPOT1-HIFI to calibrate flip angles and adding a B0-related parameter with multiple…
Effect of external normal and parallel electric fields on 180° ferroelectric domain walls in PbTiO₃.
Research
RF Safe Research Library
Jan 1, 2011
This modeling study applies uniform electric fields parallel and normal to 180° ferroelectric domain walls in PbTiO3 and computes equilibrium structures using anharmonic lattice statics. The authors report that electric fields can substantially increase domain wall thickness and identify a critical field Ec above…
Frequency-dependent electrodeformation of giant phospholipid vesicles in AC electric field.
Research
RF Safe Research Library
Jan 1, 2010
This paper presents a theoretical model of giant phospholipid vesicle deformation in an alternating-current electric field, based on minimizing membrane bending energy and electric-field energy. The model treats the membrane and surrounding aqueous media as leaky dielectrics and reports good quantitative agreement…
A rapid and facile synthesis of nanofibrillar polyaniline using microwave radiation.
Research
RF Safe Research Library
Jan 1, 2010
This engineering study describes a microwave-assisted method to synthesize polyaniline (PANI) nanofibers. Reported yields under microwave irradiation were similar to conventional synthesis but achieved in minutes rather than hours. Structural and morphological characterization (FTIR, Raman, SEM, TEM) reportedly…
Orientation and Dynamics of ZnO Nanorod Liquid Crystals in Electric Fields.
Research
RF Safe Research Library
Jan 1, 2010
This materials study reports that ZnO nanorod polymer hybrids can form liquid-crystalline phases and exhibit orientation switching under an applied AC electric field. The orientation reportedly changes from planar to homeotropic, analogous to switching in low-molecular liquid crystals. Dielectric measurements and…
Ohmic heating of peaches in the wide range of frequencies (50 Hz to 1 MHz).
Research
RF Safe Research Library
Jan 1, 2010
This engineering/food science study examined ohmic heating of peaches at 60 V/cm using bipolar pulses across frequencies from 50 Hz to 1 MHz. Heating time to a target temperature and multiple electrical properties were frequency-dependent, particularly for intact tissue. The authors report faster electro-thermal…
Disintegration efficiency of pulsed electric field induced effects on onion (Allium cepa L.) tissues as a function of pulse protocol and determination of cell integrity by ¹H-NMR relaxometry.
Research
RF Safe Research Library
Jan 1, 2010
This experimental study examined how pulsed electric field (PEF) processing parameters affect cell membrane rupture in onion tissue disks, using ion leakage as the primary integrity measure. Disintegration efficiency increased with field strength up to 500 V/cm and varied with pulse width, pulse number, and…
Electrooptical effects in colloid systems subjected to short pulses of strong electric field.
Research
RF Safe Research Library
Jan 1, 2010
This study describes an electrooptical technique for polydisperse colloid solutions using short pulses of strong sine-shaped electric field, intended for systems that cannot withstand prolonged field exposure. The authors report that key particle parameters can still be extracted from the resulting experimental data.…
High magnetic field induced charge density waves and sign reversal of the Hall coefficient in graphite.
Research
RF Safe Research Library
Jan 1, 2010
This condensed-matter study investigates highly oriented pyrolytic graphite under very strong magnetic fields at low temperature. It reports a magnetic-field-induced charge density wave transition and a subsequent sign reversal of the Hall coefficient from negative to positive. The reported angular dependence…
Effects of magnetic field and pressure on the intermediate valence state of YbPd.
Research
RF Safe Research Library
Jan 1, 2010
This condensed-matter physics study examined how high magnetic fields and pressure affect magnetization, transport, and thermodynamic properties of the intermediate-valence compound YbPd. The authors report that the Yb valence state and two first-order transitions are stable up to 55 T, while increasing pressure…
Magnetodeformation effects and the swelling of ferrogels in a uniform magnetic field.
Research
RF Safe Research Library
Jan 1, 2010
This laboratory/materials study examined deformation and swelling of magnetic field sensitive polymer gels (ferrogels) in a static, uniform magnetic field. The authors report that gels with randomly distributed magnetic particles exhibited weak magnetodeformation, whereas gels with aligned particles showed no…
Pressure and magnetic field dependence of valence and magnetic transitions in EuPtP.
Research
RF Safe Research Library
Jan 1, 2010
This laboratory study investigates how magnetic field and pressure affect valence and magnetic transitions in the compound EuPtP. High-field analysis suggests a mixed valence state at low temperature and discontinuous changes in Eu2+ fraction at two transition temperatures. Pressure increases the transition…
Thermodynamic behavior of the XXZ Heisenberg s = 1/2 chain around the factorizing magnetic field.
Research
RF Safe Research Library
Jan 1, 2010
This paper theoretically investigates zero- and finite-temperature behavior of an anisotropic antiferromagnetic Heisenberg XXZ spin-1/2 chain under a transverse magnetic field, focusing between the factorizing and critical fields. It reports an entanglement phase transition at the factorizing field where entanglement…
Effect of two length scales on the properties of MgB(2) for arbitrary applied magnetic field.
Research
RF Safe Research Library
Jan 1, 2010
This paper analyzes anomalous magnetic-field and temperature dependences observed in MgB(2) superconductivity experiments using a two-order-parameter Ginzburg-Landau theory with two length scales. The authors numerically solve the nonlinear Ginzburg-Landau equations for arbitrary applied fields between Hc1 and Hc2 to…
The modulation of the de Haas-van Alphen effect in graphene by electric field.
Research
RF Safe Research Library
Jan 1, 2010
This theoretical/physics paper examines how an in-plane uniform electric field affects the de Haas-van Alphen (dHvA) effect in graphene. It reports that magnetization, magnetic susceptibility, and dHvA oscillation behavior depend on a dimensionless parameter β = E/(vF B), with divergences described at a critical…
Spin polarization induced by in-plane electric and magnetic fields in two-dimensional heavy-hole systems.
Research
RF Safe Research Library
Jan 1, 2010
This theoretical study uses a nonequilibrium Green function approach to analyze current-induced spin polarization in a two-dimensional heavy-hole system with cubic Rashba spin-orbit coupling under in-plane electric and magnetic fields. The authors report monotonic decreases in longitudinal conductivity with…
An extension of the Czjzek model for the distributions of electric field gradients in disordered solids and an application to NMR spectra of 71Ga in chalcogenide glasses.
Research
RF Safe Research Library
Jan 1, 2010
This paper discusses the Czjzek model for distributions of electric field gradient (EFG) tensors in disordered solids and highlights its underlying assumptions and characteristics. It then introduces an extended model that combines a defined local EFG environment with an adjustable Gaussian (Czjzek) noise term to…
Slow relaxation of magnetoresistance in AlGaAs-GaAs quantum well structures quenched in a magnetic field.
Research
RF Safe Research Library
Jan 1, 2010
This study reports slow relaxation of magnetoresistance in selectively doped p-GaAs-AlGaAs structures following application of a magnetic field. The authors emphasize efforts to rule out temperature fluctuation artifacts and state that the main relaxation features remain. They interpret the phenomenon using a…
Electric field induced structuring in clay-oil suspensions: new insights from WAXS, SEM, leak current, dielectric permittivity, and rheometry.
Research
RF Safe Research Library
Jan 1, 2010
This laboratory/engineering study examined electric-field-induced structuring in clay-oil suspensions using WAXS, SEM, rheometry, and electrical measurements. Particle orientation was quantified via an orientational order parameter derived from diffraction peak azimuthal changes, and chain versus column formation was…
The influence of temperature and electric field history on the conductivity of the charge density wave system o-TaS3.
Research
RF Safe Research Library
Jan 1, 2010
This laboratory study examined how temperature and prior electric-field exposure affect low-field conductivity in the charge density wave material o-TaS3. Conductivity differed between cooling and heating below the CDW transition, and applying increasing electric fields drove the system toward a stable,…
Disordered electrical potential observed on the surface of SiO2 by electric field microscopy.
Research
RF Safe Research Library
Jan 1, 2010
This study characterizes the electrical potential on the surface of ~300 nm SiO2 grown on single-crystalline Si under ambient conditions using electric field microscopy. It reports an inhomogeneous surface potential with fluctuations up to ~0.4 V over ~1 µm regions. The authors propose these fluctuations could affect…
Radiofrequency microtenotomy for the treatment of plantar fasciitis shows good early results.
Research
RF Safe Research Library
Jan 1, 2010
This small clinical case series evaluated TOPAZ radiofrequency coblation microtenotomy for recalcitrant plantar fasciitis in 14 patients. The abstract reports improved AOFAS hindfoot scores at 3 and 6 months and improvements in several SF-36 domains, with most patients reporting good-to-excellent satisfaction. The…
Nanocrystalline hydroxyapatite bioceramic using microwave radiation: Synthesis and characterization.
Research
RF Safe Research Library
Jan 1, 2010
This engineering/materials study synthesized nanocrystalline hydroxyapatite bioceramic powder using microwave radiation and then characterized the resulting material. The authors report highly crystalline HAp nanopowder with nanoscale size, mixed morphology, and elemental composition consistent with the HAp phase.…
The effects of microwave emitted by cellular phones on ovarian follicles in rats
Research
RF Safe Research Library
Jan 1, 2009
This animal study examined whether prenatal exposure to mobile phone microwaves affects ovarian development in rats. Pregnant rats were exposed to a phone placed under the cage throughout pregnancy, with mostly standby exposure and brief periodic speech-mode exposure. Female pups assessed at 21 days had fewer ovarian…
[Treatment of benign prostatic hyperplasia by radiofrequency (TUNA): a monocentric study of 28 cases treated in ambulatory surgery].
Research
RF Safe Research Library
Jan 1, 2009
This monocentric study evaluated outpatient feasibility and outcomes of radiofrequency transurethral needle ablation (TUNA) for benign prostatic hyperplasia in patients who did not respond to medical therapy. In the outpatient subgroup, urinary symptom scores, quality of life, flow measures, and residual urine…