Ferrite Material Characterization in a Static Bias Field for the Design of a Tunable Cavity
During the development of ferrite-loaded accelerating cavities, the electromagnetic properties of the dispersive ferrite material need to be known. We describe a coaxial short-circuit measurement technique to measure the complex permeability of toroidal-shaped samples (127mm outer and 70mm inner diameter) that are exposed to an external magnetic bias field. The external magnetic bias field is applied perpendicular to the RF magnetic field. With this method it is possible to characterize the frequency dependence of the permeability for a frequency range of 1100MHz. The dependence of the permeability on the external magnetic bias is presented for the ferrite G-510 from Trans-Tech Inc. and the material characterization is shown in the same frequency range. The measurement results are verified by simulations of the measurement set-up.
Preliminary Design of a Perpendicular Biased Ferrite Loaded Accelerating Cavity
A ferrite loaded accelerating cavity with a frequency sweep of 18 to 40 MHz is studied for a possible upgrade of the CERN accelerator complex. The resonance frequency of a ferrite loaded cavity shifts by applying an external magnetic bias field to the ferrite material by means of changing the relative permeability. We present the electromagnetic design of such a cavity with a special emphasis on the modeling of the nonlinear, anisotropic and dispersive characteristics of the ferrite’s relative permeability above magnetic saturation. For experimental crosscheck, a ferrite loaded resonant test setup was built which provides results for the material performance in a magnetic bias field. A comparison of numerical simulations and experimental measurements is shown and calculations are benchmarked by measurement data. Based on this study a preliminary design of a ferrite loaded accelerating cavity is described.
Production of new antituberculosis drug and other medical preparations by electron beam treatment
Abstract Possibility of electron beam usage for immobilization of hydrazidum of an isonicotinic acid (HIA) on dextrane was studied to produce a drug for treatment of a tuberculosis. As a result of irradiation of dextrane the processes of oxidation and formation of polysaccharide occur due to carbonyl groups which are to link isoniasidum. The HIA immobilized on dextrane may be used as an effective medical preparation having prolonged action for action on endo and extracellular population of Micobacterium tuberculosis .