Authors:C. Constantinescu, E. Morîntale, Ana Emandi, Maria Dinescu, and P. Rotaru
and coordinative compounds, polymers, bio- and hybrid metal-organic materials can be fabricated employing an alternative technique, known as MAPLE (matrix assisted pulsed laser evaporation) [ 11 – 13 ]. This recent technique is a versatile way of
The aim of this paper is to find a closed form of the integrals ∫
= 0, 1, 2, … using the Maple computer algebra system. Although Maple 10 is not capable to calculate these integrals in one step, it turns out to be a very useful tool to solve this and similar kind of complex mathematical problems. During the problem solving process Maple proves that it is useful and, what is more, it is an indispensable partner. Maple helps us to formulate our conjecture, acts as an advisor and, last but not least, performs complex symbolic calculation instead of us.
Fifteen maple syrups were analyzed for137Cs and K (via40K) by using a low-background -ray counting system, and for B and K by using neutron capture prompt -ray activation analysis (PGAA). For low-background -ray counting, 3 limits of detection (24-hour counts) were 0.03 Bq137Cs/kg and 10 mg K/kg for 3.5-L portions and 0.08 Bq137Cs/kg and 20 mg K/kg for 1.0-L portions. K concentrations determined by the two methods (using 2-g portions for PGAA) were in excellent agreement. The products were obtained in 1991, with one produced in Maryland, three in New York, four in Pennsylvania, two in New Hampshire, and five in Canada. The average activity concentration for Canadian syrups (2.8 Bq137Cs/kg) was nearly a factor of 20 greater than the average (0.15 Bq137Cs/kg) for the other syrups, but all137Cs activity concentrations were at least 100 times lower than those for which controls would be recommended according to Federal Radiation Council guidance. The data exhibited distinct groupings related to the sources of the products when the ratios of137Cs activity to K content (BqCs/mgK) were plotted vs. B concentrations.
Authors:A. Rotaru, Catalin Constantinescu, P. Rotaru, Anca Moanţâ, M. Dumitru, Margareta Socaciu, Maria Dinescu, and E. Segal
A new synthesized 4CN type azomonoether, exhibiting dying properties, crystalline nature and generating interest as a material
for non-linear optical applications was investigated. Modern devices incorporating liquid crystals tend to use thin films
of such materials because of their special characteristics. Thermal stability studies are indispensable before attempting
any deposition experiment.
We have investigated the thermal behaviour of 4-[(4-chlorobenzyl)oxy]-4′-cyano-azobenzene (TG, DTG, DTA and DSC) in inert
flow atmosphere, under non-isothermal conditions. The phase transitions were studied by repeated heating-cooling regimes,
with intercalated isothermal steps. The thin films were deposited on silicon and quartz substrates by matrix assisted pulsed
laser evaporation (MAPLE) using a Nd:YAG laser working at 266 nm. FTIR spectroscopy of the obtained thin films confirmed the
preservation of the compound’s structure.
Klincsik M., Maróti Gy. Maple, (in Hungarian) Livermore , 2006.
Heck A. Introduction to Maple, Springer Verlag , New York, Inc. 1993.
Monagan M. B., Geddes K. O., Heal K. M., Laban G., Vorkoetter. J
Authors:B. Zólyomi, A. Horváth, B. Kevey, and G. Lendvai
This paper presents the so far only partially published research material of the late Bálint Zólyomi on one of his major fields of interest, the forest steppe vegetation. The phytosociological tables presented here were found in his bequest indicating that he was going to publish a grand synthesis on this topic, which, however, has not come true. Since no written text accompanied the original tables, a historical overview and a short explanation to the tables are also provided.