Synthesis and spectral studies of macrocyclic mono- and binuclear gadolinium(III)complexes derived from schiffs bases

363-366A series of mono- and binuclear Gadolinium(III) macrocyclic complexes have been prepared by the condensation of schiff's bases with the precursor compound 4,4'-dimethyl(2,2' -diformyl-6,6' -piperazine-1,4-di-ylmethylene) bis phenol in template method. All the binuclear complexes 'have been prepared in situ from their corresponding mononuclear complexes without isolation. The phenolate oxygen atom of the binucleating ligands behaves as a bridging group between two metals. The complexes have been characterized by elemental analysis, IR, NMR, UV spectra. The ESR spectral study was carried out for some complexes. The results of elemental analysis of the complexes are in good agreement with the theoretical value. Conductivity studies reveal that all the complexes are neutral

Synthesis and characterization of <img src='/image/spc_char/micro.gif' border=0>-phenoxo-bridged binuclear copper(II) complexes derived from binucleating ligands

29-34The new pentadentate binucleating symmetrical ligand 2,6-bis [N-(3,5-dichloro-2-hydroxybenzyl)-N-cyclohexylamino-methyl]-4-methylphenol (H3L1) has been prepared and its binuclear copper(II) complexes of the general formula [Cu2L(X)], where X = OH (perchlorato counter ion complexes), OAc, NO3 have been prepared. Their spectral properties and catecholase activities were studied. New unsymmetrical ligands and their complexes have also been synthesized. The phenolate oxygen atom of the binucleating ligands behaves as a bridging group. Conductivity studies showed that all the complexes are neutral. ESR spectra of the complexes show a broad band centred at 3500 G with no hyperfine splittings. The observed room temperature magnetic studies were found to be less than spin only value for d9 system. The rate constants of the complexes for the oxidation of catechol to o-quinone were in the range of 0.7210-3 to 15.010-3 min-1

Iron segregation in LEC InP crystals

Following the recent results about activation of iron diffused in InP we tried to increase the fraction of electrically active Fe atoms in InP crystals grown by the Liquid Encapsulation Czochralski method (LEC) by applying a type of `in-situ' annealing. Actually, by varying the pulling rate and the cooling rate, we observed that the Feactive/Fetotal ratio can be modified. Though the ratio is normally ranging between 0.60 and 0.70, it is found that the ratio is slightly higher corresponding to low pulling rates and considerably lower for pulling rates &gt;14 mm/h. The purpose of this paper is that of showing how these growth parameters affect the Feactive/Fetotal ratio

QA of intensity-modulated beams using dynamic MLC log files

To evaluate the utility of Dynalog file information for planar dose verification in IMRT QA, a program is developed to convert Dynalog file data to DMLC field files. For this study, five predefined fluencies are planned and delivered using Varian, Eclipse 3D planning system and 6MV photon beam of Varian, Clinac DMX linear accelerator. To measure planar dose distribution, Kodak, EDR2 films are exposed in similar setup as planning setup. Dynalog files are recorded for each delivery and converted into DMLC field files using in-house program. Delivered dose distributions are calculated using DMLC field files from Dynalog files. Planned, Measured and Delivered dose distributions are compared using gamma evaluation in Scanditronix, Omni Pro IMRT software. The Planned and Delivered planar dose distributions agree within 2% dose difference and 2 mm DTA. Measured dose distributions agree within 4% dose difference and 4 mm DTA with Planned dose distribution. Our results show Dynalog file as a promising tool for dynamic IMRT QA