2011 - Europe Direct Iasi

EUROINVENT 2011
thermal treatment), favoring appearance of a large
magnetoresistance effect. The magnetic behavior of the Zn-Co
thin films is determined by their morphology produced during
the electrodeposition, and modified as a consequence of the
subsequent thermal treatment. The coercivities of the samples
increase after thermal treatment at 350 o C. We have found by
torsion magnetometer measurements that magnetic anisotropy
easy axis is out of plane for as-deposited films and there is an
antiferromagnetic type of interaction between grains.
Magnetoresistance (MR) measurements were carried out in dc
magnetic field by means of current in plane device configuration.
We obtained the magnetoresistance values comprised between
5% and 35% for the samples after thermal treatment. The large
magnetoresistance effect obtained for the Zn-Co thin films after
thermal treatment makes them useful for technological
applications in the domain of magnetoresistive sensors with good
corrosion resistance.
R.25.
Title Microwave assisted synthesis of blue luminophors
Gheorghiţă Zbancioc, Costel Moldoveanu, Vasilichia Bejan and
Authors
Ionel Mangalagiu
Institution Al.I. Cuza University, Faculty of Chemistry
Recent studies show that pyrrolopyridazine (PP) derivatives
represent such a class, being a ‘pure’ blue-emitting moiety.
Microwave irradiation has become an increasingly valuable tool
in organic chemistry, since it offers a versatile and facile
pathway in a large variety of syntheses. Solid phase reactions
have the great advantage of using no organic solvents (‘solventfree’),
such reactions being more environmentally friendly and
generate less side products. The application of microwave
irradiation under solvent-free conditions enables organic
reactions to occur expeditiously at ambient pressure, providing
unique chemical processes with special attributes such as higher
Description
yields, shorter reaction time, milder conditions and the associated
ease of manipulation.
The aim of this work was to synthesise new fluorescent PPs, to
study the relationship between optical properties and structure
(the effect of substituents and conjugation), and to develop a new
environmentally friendly method for preparation of these
derivatives using MW technologies (in liquid and solid phase).
Application
Synthesis of highly fluorescent derivatives with extended πconjugation
stirs strong interestbecause of their applications as
sensors and biosensors, electroluminescent materials, lasers and
other optoelectronic devices.
Innovative Researches
151