Over the last ten years, the number of minimally invasive interventional procedures has been increasing steadily. Magnetic resonance imaging (MRI) is still far less frequently used for image-guided ...percutaneous procedures or as an intervention method than computed tomography (CT) and ultrasound (US). However, MRI has many advantages, such as lack of ionizing radiation, real-time MR-fluoroscopy placement high resolution, no bone and gas artifacts, the ability to display lesions that are difficult to observe on CT and US visualization of blood vessels without a contrast agent, free selection of imaging planes and in the case of procedures such as thermos or cryoablation it is possible to make an intraprocedural assessment of the process without the application of a contrasting agent (Marini et al. in Diagn Interv Imaging 102: 531–538,
2021
; Li et al. in BMC Cancer 21: 366,
2021
; Barkhausen et al. in Rofo 189: 611,
2017
). Furthermore, in addition to its use in Interventional Radiology, MRI is also becoming a reality in cardiology thanks to the possibility of overcoming all the limits related to the fusion technology used up to now in cardiac ablations (Chubb et al. Arrhythm Electrophysiol Rev 6: 85,
2017
). Some suites have been built in Northern Europe and in the United States, but based only on personal experience and industry indication. In our hospital, we have built a new Interventional Magnetic Resonance Imaging Suite (IMRIS), the first in Southern Europe and we have defined what the necessary requirements and equipment were for the safety of the patient and the operator.
Rare earth magnets based upon neodymium-iron-boron (NdFeB) are employed in many high tech applications, including hard disk drives (HDDs). The key elements in manufacturing NdFeB magnets are rare ...earth elements (REEs) such as neodymium. This element has been subject to significant supply shortfalls in the recent past. Recycling of NdFeB magnets contained within waste of electrical and electronic equipment (WEEE) could provide a secure and alternative supply of these materials. Various recycling approaches for the recovery of sintered NdFeB magnets have been widely explored. Hydrogen decrepitation (HD) can be used as a direct reuse approach and effective method of recycling process to turn solid sintered magnets into a demagnetised powder for further processing. In this work, sintered Nd-Fe-B magnets were processed without prior removal of the metallic protective layer using the thermal HD process as an alternative recycling method. The gas sorption analyzer was used to determine the quantity of the hydrogen absorbed by a samples of magnets, under controlled pressure (1, 2, 3, and 4 bar) and temperature (room, 100, 300, and 400?C) conditions, using Sieverts? volumetric method. The composition and morphology of the starting and the extracted/disintegrated materials were examined by ICP, XRD, and SEM-EDS analysis.
Octametallic and Hexadecametallic Ferric Wheels Jones, Leigh F.; Batsanov, Andrei; Brechin, Euan K. ...
Angewandte Chemie (International ed.),
November 15, 2002, Letnik:
41, Številka:
22
Journal Article
Recenzirano
Wheels of iron: The synthesis, structure, and initial magnetic properties of two new ferric wheels are reported; these are the first examples of unsupported octametallic and hexadecametallic (see ...picture) iron wheels.
This paper has twofold purpose. Firstly, an assessment method aimed to evaluate R&D strategic performance indicators is introduced. The proposed framework is based on fuzzy set theory which ...represents an adequate tool for quantitatively describing the vague and ambiguous nature of the R&D function. The second purpose of the paper is to analyze relevant R&D performance indicators in Magneti Marelli S.p.A. Serbia, a leading supplier in Serbian automotive industry. Specific findings of this empirical analysis are discussed and suggestions for further research are provided.
The structural neuroimaging findings in mood disorders were reviewed, to evaluate evidence for a neuroanatomic model of pathophysiology, involving the prefrontal cortex, the basal ganglia, the ...amygdala-hippocampus complex, thalamus, and connections among these structures. Global atrophy is not consistently found. The best replicated finding is an increased rate of white matter and periventricular hyperintensities. A smaller frontal lobe, cerebellum, caudate, and putamen appear present in unipolar depression. A larger third ventricle, and smaller cerebellum and perhaps temporal lobe appear present in bipolar disorder. These localized structural changes involve regions that may be critical in the pathogenesis of mood disorders. Generalized and localized anatomic alterations may be related to age or vascular disease. The clinical and biological correlates of these changes need to be investigated to allow development of a more complete model of pathophysiology of mood disorders.
This paper has twofold purpose. Firstly, an assessment method aimed to evaluate R&D strategic performance indicators is introduced. The proposed framework is based on fuzzy set theory which ...represents an adequate tool for quantitatively describing the vague and ambiguous nature of the R&D function. The second purpose of the paper is to analyze relevant R&D performance indicators in Magneti Marelli S.p.A. Serbia, a leading supplier in Serbian automotive industry. Specific findings of this empirical analysis are discussed and suggestions for further research are provided.
For electrical motors, three translational (x-y-z) and two tilting (θ x -θ y ) motions of the rotor must be restricted. Ball bearings are commonly used for motion restrictions; however, they cannot ...be applied to high-speed motors with large DN values. The rotor in this study has aerostatic bearing support in radial (x-y) and tilting (θ x -θ y ) motions. However, if an additional magnetic bearing/actuator is applied to the motor for axial motion control (z), the motor size and shaft length increase. To avoid this problem, a novel bearingless motor structure with a magnetically integrated bearing function was developed in this study. The structure combines the functions of both torque production (θ z ) and axial force generation (z) in one unit. It uses only a set of three-phase slotless windings and three-phase voltage source inverter. Such bearingless motors are referred to as single-drive bearingless motors. The d-axis and q-axis currents regulate the axial suspension force and torque, respectively. This paper presents the structure, operation principle, 3D-finiete element calculation results, and experimental results. The fabricated prototype bearingless motor with a shaft diameter of 30 mm can actively control the axial motion of the rotor at 60,000 rpm, that is, with a DN value of 1,800,000.
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