Authors:Cynthia Ferrari, Maria Baccia, A. Ibanez, and A. Hernandes
Pure Er:YAB (Er:YAl3(BO3)4) nanometer-sized crystalline powder was produced from low cost chemical route, the polymeric precursor method. The initial
homogeneous solutions were heat treated from 200 to 700°C under oxygen atmosphere and the unique crystalline phase was synthesized
at around 1150°C. The thermal treatments and the initial stoichiometry play a very important role on the Er:YAB preparation.
The thermal events of amorphous precursor resins and the crystallization process up to phase formation were investigated.
Authors:A. A. Ferrari, E. J. França, E. A. N. Fernandes, and M. A. Bacchi
The exogenous material that adheres to the leaf surface affects the elemental composition of the plant itself, thereby constituting
one of the major error sources in plant analysis. The present work investigated the surface contamination of leaves from the
Atlantic Forest. Instrumental neutron activation analysis (INAA) was applied to assess the efficiency of leaf EDTA-washing.
Chemical element concentrations were corrected using Sc (soil tracer) since resuspended soil is the main source of contamination
in leaves. As a result, EDTA-washing should be used mainly for the evaluation of terrigenous elements, while the Sc-corrected
concentrations are considered satisfactory for the other elements.
Authors:G. Suber, M. Bertolotti, C. Sibilia, A. Ferrari, and F. Genel Ricciardiello
Transverse photothermal deflection spectroscopy(PDS) is applied for the determination of thermal diffusivities of solid surfaces. The theory of PDS is briefly recalled and some approximated analytical formulae concerning the transverse configuration are derived. In materials where the thermal diffusivity is smaller than that of the air, the dependence of the deflection angle on the displacement between pump and probe beams is shown to have a minimum that relates to the thermal diffusivity, thereby allowing its straightforward measurement. Measurements carried out on Al2O3 samples with different porosities at room temperature show a good agreement between experiment and theory.
Authors:M. Bertolotti, A. Ferrari, C. Sibilia, M. Tamburrini, F. J. Bordoni, and P. Jani
An interferometric method is described for the determination of small deformations of a solid surface when heated by a c.w. gaussian laser beam, from which temperature increase and thermal parameters can be derived. A discussion of the method is presented and applied to the measurement of thermal conductivity, for two different situations of an unrestrained or restrained sample heated with a c.w. laser. Experimental results are finally given for a semiconductor crystal of Si.
Authors:T. Martins, E. De Nadai Fernandes, A. Ferrari, M. Bacchi, and F. Tagliaferro
The tomato culture demands large quantities of mineral nutrients, which are supplied by synthetic fertilizers in the conventional
cultivation system. In the organic cultivation system only alternative fertilizers are allowed by the certifiers and accepted
as safe for humans and environment. The chemical composition of rice bran, oyster flour, cattle manure and ground charcoal,
as well as soils and tomato fruits were evaluated by instrumental neutron activation analysis (INAA). The potential contribution
of organic fertilizers to the enrichment of chemical elements in soil and their transfer to fruits was investigated using
concentration ratios for fertilizer and soil samples, and also for soil and tomato. Results evidenced that these alternative
fertilizers could be taken as important sources of Br, Ca, Ce, K, Na and Zn for the organic tomato culture.
Authors:T. Martins, E. De Nadai Fernandes, A. Ferrari, F. Tagliaferro, and M. Bacchi
The agricultural supplies used in the organic system to control pests and diseases as well as to fertilize soil are claimed
to be beneficial to plants and innocuous to human health and to the environment. The chemical composition of six agricultural
supplies commonly used in the organic tomato culture, was evaluated by instrumental neutron activation analysis (INAA). Results
were compared to the maximum limits established by the Environment Control Agency of the São Paulo State (CETESB) and the
Guidelines for Organic Quality Standard of Instituto Biodinâmico (IBD). Concentrations above reference values were found for
Co, Cr and Zn in compost, Cr and Zn in cattle manure and Zn in rice bran.
Authors:M. Angiuli, C. Ferrari, L. Lepori, E. Matteoli, G. Salvetti, E. Tombari, A. Banti, and N. Minnaja
Extra Virgin olive oils
(7 samples) originating from different areas of Tuscany, defective olive oils
(5 samples), commercial edible seed oils (4 samples) and two commercial samples
of olive oil (one declared ‘extra virgin olive oil’ and one ‘olive
oil’) were studied by different calorimetric techniques: high sensitivity
isothermal, differential scanning, and modulated scanning calorimetry. The
temperature interval (–60) – (+30)C was explored for monitoring: i) the main features of the liquid↔solid phase
transitions, ii) the nucleation and growth
rate of the polymorphous crystalline phases of the triacylglicerols, and iii) the melting process. This investigation was
planned for verifying the utility and effectiveness of calorimetry for screening
quality and origin of olive oil. To this end, the main calorimetric operation
modes have been applied, the experimental results reported and their utility
for developing an effective and reliable screening protocol discussed.
Authors:A. Ferrari, E. De Nadai Fernandes, F. Tagliaferro, M. Bacchi, and T. Martins
Tomato is amongst the most consumed vegetables in the world, not only for its culinary versatility but also for its high nutritional
value. In the last years, consumers have shown an increased concern regarding food origin and safety. The organic tomato production
has been a promising alternative for the consumer offering a safer food in relation to environmental, social and nutritional
aspects. This study assessed the chemical composition of tomato seeds produced in both conventional and organic systems by
INAA. The results showed significant differences (p≤0.05) in the mass fractions of Br, Cs, Eu, Fe, K, Mo, Na, Rb and Sm between both systems, indicating influence of the crop
management adopted in the different tomato production systems.