introduction:  90 sr/ 90 y source  has  been  used  for  the  intravascular  brachytherapy  to  prevent  coronary  restenosis in the patients who have undergone angioplasty. the aim of this research is to determine the  dose distribution of  90 sr/ 90 y source in a water phantom.  materials  and  methods:  in  the  present  work,  mcnp  code  has  been  applied  to  calculate  the  dose  distri...

Introduction:  90 Sr/ 90 Y source  has  been  used  for  the  intravascular  brachytherapy  to  prevent  coronary  restenosis in the patients who have undergone angioplasty. The aim of this research is to determine the  dose distribution of  90 Sr/ 90 Y source in a water phantom.  Materials  and  Methods:  In  the  present  work,  MCNP  code  has  been  applied  to  calculate  the  dose  distri...

An extrapolation minichamber was developed for measuring doses from weakly penetrating types of radiation. The chamber was tested at the radiotherapeutic dose level in a beam from a (90)Sr+(90)Y check source, in a beam from a plane (90)Sr+(90)Y ophthalmic applicator, and in several reference beams from an X-ray tube. Saturation, ion collection efficiency, stabilization time, extrapolation curve...

A joint experimental/theoretical study has been carried out on the putative MMA polymerization catalyzed by an yttrium isopropyloxide complex. Despite its high activity in lactone polymerization, this catalyst is found to be unreactive on methyl methacrylate (MMA) polymerization. This surprising result is rationalized using a computational approach at the DFT level. Indeed, the endothermicity o...

The preparation of yttrium metal by the reduction of yttrium trifluoride with calcium is described. Alternate methods employing the formation of a low melting Y-Zn or Y-Mg intermediate alloy are evaluated and data on chemical and microscopic purity of the resulting metal are presented.

PURPOSE In this study, we attempted to obtain full dosimetric data for a new (90)Y brachytherapy source developed by the College of Chemistry (Sichuan University) for use in high-dose-rate after-loading systems. MATERIAL AND METHODS The dosimetric data for this new source were used as required by the dose calculation formalisms proposed by the AAPM Task Group 60 and Task Group 149. The active...

Ligand substitution reactions and catalytic hydroamination/cyclization of aminoalkenes have been studied with a new oxazolinylborato yttrium compound, tris(4,4-dimethyl-2-oxazolinyl)phenylborato bis(trimethylsilylmethyl)yttrium ([Y(kappa(3)-To(M))(CH(2)SiMe(3))(2)(THF)], 1). THF exchange in 1 is rapid at room temperature, and activation parameters obtained by simulation of (1)H NMR spectra acqu...

Dermatological and ophthalmic applicators are used in brachytherapy for the treatment of superficial lesions of skin and eyes. The calibration of these applicators should be realized periodically, according to quality control programs and international recommendations about dosimetry and calibration of brachytherapy sources. Thin thermoluminescent dosimeters of CaSO4:Dy were utilized in this wo...

Chiral alkyl or amido yttrium complexes were prepared from N-silyl- or N-cyclopentyl-substituted binaphthylamido ligands. According to the synthetic procedure, these complexes could be obtained in their neutral form or as heterobimetallic complexes in the presence of 1 equiv. LiCl. These new species were characterized by IR and NMR spectroscopies, elemental analyses and some of them by X-ray di...