A piezoelectric force sensor is suggested for magnetic force microscopy (MFM) purposes. Added between the piezoelectric resonator and the magnetic probe is a mechanical force amplifier in the form of a thin, long resonant arm with an integral micro-rod whereby the amplitude of the force acting on the probe is amplified by a factor of 20 to 40 at a low noise level. When the sensor was operated in air, its noise floor was found to be 1.
View Article and Find Full Text PDFOne of the future applications of magnetic nanoparticles is the development of new iron-oxide-based magnetic resonance imaging (MRI) negative contrast agents, which are intended to improve the results of diagnostics and complement existing Gd-based contrast media. Iron oxide nanoparticles designed for use as MRI contrast media are precisely examined by a variety of methods: powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, Mössbauer spectroscopy and zero-field nuclear magnetic resonance (ZF-NMR) spectroscopy. TEM and XRD measurements reveal a spherical shape of the nanoparticles with an average diameter of 5-8 nm and a cubic spinel-type crystal structure of space group -3.
View Article and Find Full Text PDFMagnetic resonance imaging (MRI) is one of the most perspective methods of noninvasive visualization in medicine, and use of contrast agents significantly its potentialities extends. Iron oxide nanoparticles are promising contrast agents, but in fact all the data on their efficiency were obtained in high-field tomographs for experimental animals. We studied the possibility of using magnetic nanoparticles for MRI visualization of rat brain glioblastoma at the most common clinical field 1.
View Article and Find Full Text PDFWe studied dependences of T2 relaxation time on magnetic field and concentration of nanoparticles. It was found that nanocontrast media are effective under the influence of the magnetic fields in the range 0.3-7 T.
View Article and Find Full Text PDFThe impact of such factors as the shape of the applied voltage pulse, the friction force, and the mass of the movable part on the motor operation at low temperatures is experimentally investigated. Important added features in the motor design are support springs. These springs prevent one part of the slider clamp from shifting relative to the other during motion.
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