La Separazione mediante HPLC dei due fenoli isomeri Timolo (p-isopropil-m-cresolo) e Carvacrolo (p-isopropil-o-cresolo)

A method is described for the separation by HPLC of two isomer phenols thymol and carvacrol. Satisfactory resu1ts have been obtained by using a chromatographic column μ Bondapak ,C18 and a solvent system constitued by acetonitrile (40%) and water (60%). The flow rate was 1,5 ml/min. The use of this technique permits determination and dosage of these two phenols in essential oils

Avaliação da homogeneidade da mistura de dietas de bovinos confinados com diferentes ingredientes.

Objetivou-se avaliar a qualidade da mistura de duas dietas, homogeneizadas em vagão misturador (Tratomix 600, IPACOL), por meio da análise de MS

From the historical sugar refinery of Chichaoua (Morocco) to the lab: A reverse engineering experimentation on the hydration of earthen materials stabilized with lime

In order to explain the good state of conservation and good mechanical characteristics of the lime-stabilized earth of the sugar refinery near Chichaoua (Morocco, XVIth A.C.) XRD, SEM-EDX, TG-DSC, FT-IR analyses were performed on collected samples. Moreover laboratory earth samples were prepared with selected clay minerals (presence of attapulgite) and lime, involving a reverse engineering process in order to investigate the reaction products during curing . The same analyses performed on the historical samples were carried out on lab samples. Moreover, compressive strength was assessed. The results were compared to the ones obtained on the historical samples. The maturation of lime-stabilized rammed earth was due to lime carbonation and to earth drying and consolidation. Furthermore, the formation of mixed CSH phases was evidenced, possibly because of a slow pozzolanic reaction between lime and clays, that took place in long times both in lab and in historical samples.In order to explain the good state of conservation and good mechanical characteristics of the lime-stabilized earth of the sugar refinery near Chichaoua (Morocco, XVIth A.C.) XRD, SEM-EDX, TG-DSC, FT-IR analyses were performed on collected samples. Moreover laboratory earth samples were prepared with selected clay minerals (presence of attapulgite) and lime, involving a reverse engineering process in order to investigate the reaction products during curing . The same analyses performed on the historical samples were carried out on lab samples. Moreover, compressive strength was assessed. The results were compared to the ones obtained on the historical samples. The maturation of lime-stabilized rammed earth was due to lime carbonation and to earth drying and consolidation. Furthermore, the formation of mixed CSH phases was evidenced, possibly because of a slow pozzolanic reaction between lime and clays, that took place in long times both in lab and in historical samples

Efeito de diferentes instalações no desempenho de novilhos Nelore confinados.

O objetivo deste trabalho é verificar se as diferentes instalações podem interferir no desempenho de novilhos Nelore confinados

Existe preferência dos bovinos confinados por determinados cochos em sistema de alimentação coletivo?

Objetivou-se com este trabalho avaliar a posição dos animais dentro das baias coletivas para determinar a taxa de fidelidade a um cocho por determinado animal. Havendo preferência, seria possível atribuir o colar mais adequado para cada animal e, com isso, reduzir o tempo de aprendizado

Eficiência alimentar entre novilhos Nelore confinados em diferentes instalações.

O objetivo do trabalho é avaliar o efeito de diferentes instalações na eficiência alimentar de bovinos de corte confinados

RHESSI images and spectra of two small flares

We studied the evolution of two small flares (GOES class C2 and C1) that developed in the same active region with different morphological characteristics: one is extended and the other is compact. We analyzed the accuracy and the consistency of different algorithms implemented in RHESSI software to reconstruct the image of the emitting sources, for energies between 3 and 12 keV. We found that all tested algorithms give consistent results for the peak position whil the other parameters can differ at most by a factor 2. Pixon and Forward-fit generally converge to similar results but Pixon is more reliable for reconstructing a complex source. We investigated the spectral characteristics of the two flares during their evolution in the 3--25 keV energy band. We found that a single thermal model of the photon spectrum is inadequate to fit the observations and we needed to add either a non-thermal model or a hot thermal one.The non-thermal and the double thermal fits are comparable. If we assume a non-thermal model, the non-thermal energy is always higher than the thermal one.Only during the very final decay phase a single thermal model fits fairly well the observed spectrum.Comment: 26 pages, 11 figures, accepted by Solar Physic