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Showing results for: RF

Evaporation rate of water as a function of a magnetic field and field gradient.

Research RF Safe Research Library Jan 1, 2012

This experimental study investigated evaporation of pure water placed at different simulated gravity positions within a superconducting magnet producing a large gradient magnetic field. Water evaporation was reported to be faster in the magnetic field than without the field, and the amount evaporated varied by…

Nanosecond pulse electric field activation of platelet-rich plasma reduces myocardial infarct size and improves left ventricular mechanical function in the rabbit heart.

Research RF Safe Research Library Jan 1, 2012

This animal and in vitro study evaluated nanosecond pulsed electric fields (nsPEF) as a nonchemical method to activate platelet-rich plasma (PRP) for cardioprotection. In rabbits undergoing brief coronary occlusion followed by reperfusion, PRP injection into ischemic myocardium was associated with reduced infarct…

Nanocomposite dielectrics in PbO-BaO-Na2O-Nb2O5-SiO2 system with high breakdown strength for high voltage capacitor applications.

Research RF Safe Research Library Jan 1, 2012

This engineering materials study reports fabrication and characterization of nanocomposite dielectrics in a PbO-BaO-Na2O-Nb2O5-SiO2 glass-ceramic system. X-ray diffraction and microstructural observations describe temperature-dependent phase formation with nanometer-sized crystallites dispersed in a glass matrix. The…

Tunable optical antennas based on metallic nanoshells with nanoknobs.

Research RF Safe Research Library Jan 1, 2012

This engineering study investigates a plasmonic nanostructure composed of a spherical metallic nanoshell with a small metallic nanoparticle (“nanoknob”) on its surface. It reports tunable plasmon resonance behavior driven by nanoshell properties and localized/enhanced electromagnetic fields near the nanoknob under…

Comparison of 2 methods of non-invasive treatment between transcutaneous electrical stimulation and pulsed electromagnetic field stimulation as replacement of invasive manual acupuncture.

Research RF Safe Research Library Jan 1, 2012

This study compared two non-invasive acupoint stimulation methods—TEAS and PEMF—as alternatives to manual acupuncture for recovery from exercise-induced muscle fatigue. Using 2 Hz stimulation (PEMF magnetic flux 30.92 mT), the authors report faster recovery of EMG median frequency and improved peak torque recovery in…

[Study on dewatering of activated sludge under applied electric field].

Research RF Safe Research Library Jan 1, 2012

This engineering study investigated factors affecting electro-dewatering of activated sludge under a horizontal applied electric field. It reports optimal performance without altering sludge pH or conductivity and finds that CPAM conditioning improves and accelerates dewatering. The authors provide operating…

Model for magnetic flux patterns induced by the influence of in-plane magnetic fields on spatially inhomogeneous superconducting interfaces of LaAlO3-SrTiO3 bilayers.

Research RF Safe Research Library Jan 1, 2012

This study examines how spatial inhomogeneity affects a two-dimensional noncentrosymmetric superconductor in an in-plane magnetic field, motivated by LaAlO3-SrTiO3 interfaces. The authors report that spatial variation of Rashba spin-orbit coupling can generate local magnetic flux patterns through a field-induced…

Evaluation of the packaging and encapsulation reliability in fully integrated, fully wireless 100 channel Utah Slant Electrode Array (USEA): Implications for long term functionality.

Research RF Safe Research Library Jan 1, 2012

This engineering study evaluated long-term encapsulation and packaging reliability of a fully wireless 100-channel Utah Slant Electrode Array system in vitro. The device was soaked in PBS for over 12 months while being wirelessly powered/configured at 2.765 MHz and transmitting an FSK-modulated 900 MHz RF signal. The…

Long-term digital mobile phone use and cognitive decline in the elderly.

Research RF Safe Research Library Jan 1, 2012

This 4-year cohort study in 871 non-demented older Chinese adults examined frequent digital mobile phone use and changes in cognitive performance. The authors report no significant harmful association between phone use and cognitive functioning. They note users tended to have characteristics linked to better…

Effect of electromagnetic radiofrequency radiation on the rats' brain, liver and kidney cells measured by comet assay.

Research RF Safe Research Library Jan 1, 2011

This animal study assessed DNA damage in rat brain, liver, and kidney cells after repeated whole-body exposure to 915 MHz GSM-modulated RF radiation (SAR 0.6 W/kg) using the comet assay. Tail length was slightly increased in brain cells and differed more notably in liver and kidney samples versus sham controls, while…

Would pulsed radiofrequency applied to different anatomical regions have effective results for chronic pain treatment?

Research RF Safe Research Library Jan 1, 2011

This retrospective cross-sectional study evaluated pulsed radiofrequency (PRF) for chronic pain in patients who did not respond to conventional treatment. Across 24 patients treated at different anatomical regions, 66.7% reportedly achieved at least a 50% reduction in VAS pain scores over a mean follow-up of 8.5…

Fuzzy mobile-robot positioning in intelligent spaces using wireless sensor networks.

Research RF Safe Research Library Jan 1, 2011

This engineering study develops and experimentally evaluates a fuzzy-logic method for locating mobile robots in an intelligent space using wireless sensor networks. Localization relies on inter-node range measurements estimated from RF signal strength attenuation, which the authors describe as noisy and unreliable.…

Interoperation of an UHF RFID reader and a TCP/IP device via wired and wireless links.

Research RF Safe Research Library Jan 1, 2011

This engineering paper describes a system implementation for interoperation between a 915 MHz UHF RFID reader and a TCP/IP gateway device. The architecture uses wired communication between the TCP/IP device and RFID reader, and wireless ZigBee (IEEE 802.15.4) links to an end-device/coordinator. Web-based tests are…

Response identification in the extremely low frequency region of an electret condenser microphone.

Research RF Safe Research Library Jan 1, 2011

This engineering study describes an experimental setup using a small electret condenser microphone connected to a notebook/PC to detect extremely low frequency signals. Using a small air cell made from a drilled DVD plate with a speaker and microphone on opposite sides, the microphone captured signals in the 0.5–20…

A radiofrequency coil to facilitate B₁⁺ shimming and parallel imaging acceleration in three dimensions at 7 T.

Research RF Safe Research Library Jan 1, 2011

This paper reports the development of a 15-channel transmit-receive RF coil for 7 T human brain MRI, using a hybrid decoupling approach to support element placement along three axes. The design is presented as enabling B1+ shimming and parallel imaging acceleration in three dimensions, with reported isolation and…

Measurement of creatine kinase reaction rate in human brain using magnetization transfer image-selected in vivo spectroscopy (MT-ISIS) and a volume ³¹P/¹H radiofrequency coil in a clinical 3-T MRI system.

Research RF Safe Research Library Jan 1, 2011

This paper describes a new magnetization transfer 31P MRS approach (MT-ISIS) for measuring the creatine kinase forward reaction rate in the human brain using a volume 31P/1H RF coil on a clinical 3-T MRI system. The method aims to reduce acquisition time (30 min), avoid scalp muscle contamination, improve RF…

Increased blood oxygen level-dependent (BOLD) sensitivity in the mouse somatosensory cortex during electrical forepaw stimulation using a cryogenic radiofrequency probe.

Research RF Safe Research Library Jan 1, 2011

This engineering-focused mouse fMRI study evaluated a 400-MHz cryogenic RF probe (CryoProbe) versus a conventional room-temperature surface coil during electrical forepaw stimulation. The CryoProbe increased image SNR and temporal SNR and reduced temporal noise compared with the room-temperature coil. The authors…

Reduction of implant RF heating through modification of transmit coil electric field.

Research RF Safe Research Library Jan 1, 2011

This engineering study describes modifying MRI RF transmit coil electric-field distributions to create electric field-free zones without substantially changing transmit sensitivity. Phantom experiments are reported to show reduced implant heating when a zero electric-field plane is aligned with the implant location.…

Impact of a static magnetic field on the electricity production of Shewanella-inoculated microbial fuel cells.

Research RF Safe Research Library Jan 1, 2011

This study investigated how exposure to a static magnetic field affects electricity production in Shewanella-inoculated microbial fuel cells across different reactor configurations. A 100 mT field was reported to increase maximum voltage and the effect was described as immediate and reversible, with possible adverse…

Evaluation of magnetic resonance safety of veterinary radiofrequency identification devices at 1 T.

Research RF Safe Research Library Jan 1, 2011

This study evaluated MRI safety parameters for three commercial veterinary RFID microchips at 1 T, assessing movement forces, heating, artifacts, and device function. Translation and torque were reported to be larger than expected from normal activity, but no significant heating was observed and microchip function…

High-intensity pulsed electric fields processing parameters affecting polyphenoloxidase activity of strawberry juice.

Research RF Safe Research Library Jan 1, 2010

This study evaluated high-intensity pulsed electric fields (HIPEF) as a processing method to inactivate polyphenoloxidase (PPO) in strawberry juice. Using response surface methodology at a constant electric field of 35 kV/cm, the authors report strong PPO reductions across tested parameter ranges. Bipolar mode,…

[Dependence of the non-thermal radiofrequency electromagnetic field bioeffects on the typological features of electroencephalogram in humans].

Research RF Safe Research Library Jan 1, 2010

This volunteer study examined short-term non-thermal RF EMF exposure and reported changes in EEG spectra. The main reported effect was amplification of alpha-range energy, with the magnitude depending on baseline EEG typological features. The abstract also reports that combining RF EMF exposure with monotonous…

Electric field gradients in (111)In-doped (Hf/Zr)3Al2 and (Hf/Zr)4Al3 mixed compounds: ab initio calculations, perturbed angular correlation measurements and site preference.

Research RF Safe Research Library Jan 1, 2010

This materials-physics study investigated quadrupolar hyperfine interactions of (111)In→(111)Cd probes in polycrystalline Zr4Al3 and Hf4Al3 containing minority (Zr/Hf)3Al2 phases. The authors observed a strong preference of (111)In solutes for the minority (Zr/Hf)3Al2 phases. Ab initio EFG calculations were used to…

Surface superconducting states in a yttrium hexaboride single crystal in a tilted magnetic field.

Research RF Safe Research Library Jan 1, 2010

This experimental study examined nucleation of superconductivity at the surface of a single-crystal yttrium hexaboride (YB6) in a tilted dc magnetic field. The authors measured Hc3 on each side of the sample as a function of the angle between the field and the surface. They report Hc3/Hc2 ≈ 1.28 for a perpendicular…

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…

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