Radiofrequency heating

Up regulation of 3H-LSD binding (i.e., an increase in the B, ) was found in the hippocampus 2 weeks after 5-HT-depleting radiofrequency heat lesions of the midbrain dorsal and median raphe nuclei (103). 

Selective vaporization and deposition are performed in radiofrequency-heated tantalum distillation columns (Fig. 4). The... 

The method of choice for the preparation of Pa metal is a somewhat modified van Arkel-De Boer process, which uses protactinium carbide (Section II,C) as the starting material. The carbide and iodine are heated to form protactinium iodide, which is thermally dissociated on a hot filament 12-15). An elegant variation is to replace the filament with an inductively heated W or Pa sphere 109). A photograph of a 1.4-g sample of Pa metal deposited on a radiofrequency-heated W sphere is shown in Fig. 6. From the analytical data presented in Table V, the impurities present before and after application of this modified iodide transport process (Sections II,D and III,C) can be compared. 

In Situ Decontamination by Radiofrequency Heating Field Test U.S. Air Force, 1989, ESL-TR-88-62 (NTIS). 

Thermal processes involve heating the contaminated soil to induce volatilization and removal of contaminants (e.g., radiofrequency heating) or to melt and solidify the contaminated soil mass (e.g., vitrification). 

Many microreactors are at the research level but a few are already commercially available. Microwave-assisted flow processing in microreactors (MAFP) [93] or radiofrequency-heated flow reactors [94,95] are promising alternatives for conventionally heated, multistep production of fine chemicals in batch reactors. Realization of MAFP at an industrial scale requires a proper design of multitubular reactors integrated with microwave heating [96]. 

Houlding T, Tchabanenko K, Rahman MdT, Rebrov EV. Direct amide formation using radiofrequency heating. Org. Biomol. Chem. 2013 11(25) 4171 177. 

Kaufmann TJ, Jensen ME, Schweickert PA, Marx WF, Kallmes DF Age of fracture and clinical outcomes of percutaneous vertebroplasty. AJNR Am J Neuroradiol 2001 22 1860-3. Lieberman IH, Togawa D, Kayanja MM Vertebroplasty and kyphoplasty filler materials. Spine J 2005 5 305S-16S Liebschner MA, Rosenberg WS, Keaveny TM Effects of bone cement volume and distribution on vertebral stiffness after vertebroplasty. Spine 2001 26 1547-54 Martin JB, Jean B, Sugiu K, San Millan Ruiz D, Piotin M, Murphy K et al Vertebroplasty clinical experience and followup results. Bone 1999 25 11S-5S Masala S, Roselli M, Massari F, Fieri R, Ursone A, Fossile E et al Radiofrequency Heat Ablation and Vertebroplasty in the treatment of neoplastic vertebral body fractures. Anticancer Res 2004 24 3129-33... 

Rand, R.W. Snyder, M. Elliott, D.G. Snow, H.D. (1976), Selective radiofrequency heating of ferrosilicone occluded tissue a pjreliminary repxjrt. Bull. Los Angeles Neurol. Soc., 41 154-159. 

Dvinskikh SV, Castro V, Sandstrom D (2004) Heating caused by radiofrequency irradiation and sample rotation in C-13 magic angle spinning NMR studies of lipid membranes. Magn Reson Chem 42 875-881... 

A further refinement is to dispense with the radiofrequency hood and use the sort of stoving system traditionally used to process confectionery gum products. The biscuits are treated by blowing heated air that has been dehumidified by use of a heat pump. This system uses markedly less energy than the radiofrequency hood. 

The radiofrequency pulses involved in MRI cause thermal heating of the tissues, and are thus subject to FDA limits on the amount of RF power that is transmitted to a subject during a medical scan. The RF power unit is specified as the specific absorption rate (SAR) and is measured in watts per kilogram of body tissue (W/kg tissue). Powers that exceed this level put the subject at risk of tissue damage incurred as a result of the tissue s inability to remove the heat through blood flow. 

On this subject notice that, possibly combined with various heating methods, several physical effects may be considered which allow free flotation of solid and even liquid matter. Materials may be levitated for instance by a jet of gas, by intense sound waves or by beams of laser light. Conductors levitate in strong radiofrequency fields, charged particles in alternating electric fields, magnets above superconductors or vice versa. A review on levitation in physics with the description of several techniques and their principles and applications was made by Brandt (1989). 

Some radiation is helpful and necessary, as in the case of sunlight, which allows us to see the world. The nonionizing radiation of the sun warms us, but too much ultraviolet radiation can cause sunburn or cancer depending on our individual sensitivity. There is clearly a dose - response relationship between exposure and effect, with individual sensitivity playing an important role. Microwave and radiofrequency radiation are incredibly useful in heating and transmitting information. 

Ions generated by an electron beam from a heated filament are passed into a cubic cell where they are held by an electric trapping potential and a constant magnetic field. Each ion assumes a cycloidal orbit at its own characteristic frequency, which depends on mJz the cell is maintained under high vacuum. Originally, these frequencies were scanned by varying the electric field until each cycloidal frequency was, in turn, in resonance with an applied constant radiofrequency. At resonance, the motion of the ions of the same frequency is coherent and a signal can be detected. 

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