background: the effectiveness and safety of brachytherapy treatment is mainly concerned with the calibration of sources and their traceability to internationally accepted standards. secondary standard dosimetry laboratory (ssdl) does not offer calibration of ionization chambers with gamma-ray spectrum of high dose rate source 192ir . this work has been carried out to calibrate the high dose rat...

A hypothesis of the beam auto–focusing in the relativistic vacuum diode with a needle anode is proposed. A physical model of the effect is elaborated. As is shown, auto –focusing of high current beam can be caused by ions emitting from the anode. Initial (pre focusing) stage of focusing is provided with ionization of the gas molecules absorbed in the anode surface. Then (at quasi–steady stage),...

background: in order to deliver the precise dose to the target in radiotherapy, absorbed dose to water at the reference point should be assessed. when the calibration procedure is performed for a reference dosimeter in the 60co beam of a secondary standard dosimetry laboratory (ssdl), the total uncertainty in absorbed dose to water (dw) is estimated to be approximately 1.5%. this study attempts...

The purpose of this study was to identify the prevalence of fungal colonization in water systems and to evaluate the effect of decreasing fungal colonization by a copper-silver ionization system. Environmental samples were collected for fungal culture prospectively during a 1-year period (2011-2012) at the study hospital. A total of 392 water samples were examined from five buildings on March 1...

In the current study, we compared plastic matrix-assisted laser desorption/ionization (MALDI) plates pre-spotted with different solid ionic matrices. Data reflect that after 3 months of storage, the standards were oxidized in α-cyano-4-hydroxycinnamic acid (HCCA) whether or not in HCCA/3-acetylpyridine (3APY) and HCCA/aniline, and certain peptides, such as ubiquitin, were not detected using the...

calix(6)arene hydroxamic acids (iii) are synthesised for the first time by reactingcalix(6)arene acid chloride(ii) with substituted hydroxylamines at low temperature in the presence ofsodium bicarbonate. the p-carboxycalix(6)arene(i) is obtained by an acid catalysed condensationreaction of p-hydroxybenzoic acid and formaldehyde. these calixarenes are characterised by meltingpoint, uv, ir, 1h nm...

the ionization effects of charged particles produced in neutron interactions for boron neutroncapture therapy are considered here using srim monte carlo code. the estimated values of these effects ina plexiglas acrylic phantom are shown to agree well with the available experimental values in high boronconcentration areas. as expected, the ionization effects from lithium and alpha particles are ...