Kinetics and crystallization path of a Fe-based metallic glass alloy

The thermal stability and the quantification of the different transformation processes involved in the overall crystallization of the Fe50Cr15Mo14C15B6 amorphous alloy were investigated by several characterization techniques. Formation of various metastable and stable phases during the devitrification process in the sequence a-Fe, ¿-Cr6Fe18Mo5, M23(C,B)6, M7C3, ¿-Fe3Mo3C and FeMo2B2 (with M = Fe, Cr, Mo), was observed by in-situ synchrotron high energy X-ray diffraction and in-situ transmission electron microscopy. By combining these techniques with differential scanning calorimetry data, the crystallization states and their temperature range of stability under continuous heating were related with the evolution of the crystallized fraction and the phase sequence as a function of temperature, revealing structural and chemical details of the different transformation mechanisms.Postprint (published version

Optimization of harvest date according to the volatile composition of Mediterranean aromatic herbs at different vegetative stages

Most of the studies concerning the optimal harvest date of aromatic herbs have dealt with different parts of plant such as flowers, leaves, stems, roots and seeds, but none have evaluated the effect of different harvest date at different vegetative stages on shoots (leaves and stems). Therefore, the main objective was to investigate the effects of harvest date of two consecutive seasons on the volatile composition of shoots of 4 aromatic herbs (dill, parsley, coriander and mint) widely cultivated worldwide. The impact of harvest date during the evolution of vegetative part of four aromatic herbs (parsley, dill, coriander and mint) was investigated. Volatile compounds of shoots of the four herbs were identified by GC–MS. The main compounds were 1,3,8-p-menthatriene, betaphellandrene, myristicin and myrcene for parsley, alpha-phellandrene, dillether and beta-phellandrene for dill, decanal, E-2-dodecenal, 1-decanol and dodecanal for coriander, and carvone and limonene in case of mint. There was a significant effect of harvest date on the content of volatile compounds of the four species. The results showed that highest total concentration of volatiles and therefore the optimal harvest date of parsley was found 9 weeks after planting date with a total concentration of 2543 mg kg−1, for dill was 2619 mg kg−1 14 weeks after planting date, for coriander was 2191 mg kg−1 3 weeks after planting date, and 23329 mg kg−1 for mint 6 weeks after planting dat

Les obligacions fiscals de les entitats no lucratives

Inclou glossari, normatives de referència i altres fonts de consultaForma part de la col·lecció: Útils pràctics. Barcelona associacions; 2

In vitro effect photodynamic therapy with differents photosensitizers on cariogenic microorganisms

Background: Antimicrobial photodynamic therapy has been proposed as an alternative to suppress subgingival species. This results from the balance among Streptococcus sanguis, Streptococcus mutans and Candida albicans in the dental biofilm. Not all the photosensitizers have the same photodynamic effect against the different microorganims. The objective of this study is to compare in vitro the photodynamic effect of methylene blue (MB), rose Bengal (RB) and curcumin (CUR) in combination with white light on the cariogenic microorganism S. mutans, S. sanguis and C. albicans. Results: Photodynamic therapy with MB, RB and CUR inhibited 6 log 10 the growth of both bacteria but at different concentrations: 0.31-0.62 µg/ml and 0.62-1.25 µg/ml RB were needed to photoinactivate S. mutans and S. sanguis, respectively//1.25-2.5 µg/ml MB for both species//whereas higher CUR concentrations (80-160 µg/ml and 160-320 µg/ml) were required to obtain the same reduction in S. mutans and S. sanguis viability respectively. The minimal fungicidal concentration of MB for 5 log10 CFU reduction (4.5 McFarland) was 80-160 µg/ml, whereas for RB it ranged between 320 and 640 µg/ml. For CUR, even the maximum studied concentration (1280 µg/ml) did not reach that inhibition. Incubation time had no effect in all experiments. Conclusions: Photodynamic therapy with RB, MB and CUR and white light is effective in killing S. mutans and S. sanguis strains, although MB and RB are more efficient than CUR. C. albicans required higher concentrations of all photosensitizers to obtain a fungicidal effect, being MB the most efficient and CUR ineffective

First-order structural transition in the multiferroic perovskite-like formate [(CH3)2NH2][Mn(HCOO)3]

In this work we explore the overall structural behaviour of the [(CH3)2NH2][Mn(HCOO)3] multiferroic compound across the temperature range where its ferroelectric transition takes place by means of calorimetry, thermal expansion measurements and variable temperature powder and single crystal X-ray diffraction. The results clearly proof the presence of structural phase transition at Tt ~187 K (temperature at which the dielectric transition occurs) that involves a symmetry change from R-3c to Cc, twinning of the crystals, a discontinuous variation of the unit cell parameters and unit cell volume, and a sharp first-order-like anomaly in the thermal expansion. In addition, the calorimetric results show a 3-fold order-disorder transition. The calculated pressure dependence of the transition temperature is rather large (dTt/dP = 4.6 $\pm$ 0.1 K/kbar), so that it should be feasible to shift it to room temperature using adequate thermodynamic conditions, for instance by application of external pressure

Predicting the onset and persistence of episodes of depression in primary health care. The predictD-Spain study: Methodology

Background: The effects of putative risk factors on the onset and/or persistence of depression remain unclear. We aim to develop comprehensive models to predict the onset and persistence of episodes of depression in primary care. Here we explain the general methodology of the predictD-Spain study and evaluate the reliability of the questionnaires used. Methods: This is a prospective cohort study. A systematic random sample of general practice attendees aged 18 to 75 has been recruited in seven Spanish provinces. Depression is being measured with the CIDI at baseline, and at 6, 12, 24 and 36 months. A set of individual, environmental, genetic, professional and organizational risk factors are to be assessed at each follow-up point. In a separate reliability study, a proportional random sample of 401 participants completed the test-retest (251 researcher-administered and 150 self-administered) between October 2005 and February 2006. We have also checked 118,398 items for data entry from a random sample of 480 patients stratified by province. Results: All items and questionnaires had good test-retest reliability for both methods of administration, except for the use of recreational drugs over the previous six months. Cronbach's alphas were good and their factorial analyses coherent for the three scales evaluated (social support from family and friends, dissatisfaction with paid work, and dissatisfaction with unpaid work). There were 191 (0.16%) data entry errors. Conclusion: The items and questionnaires were reliable and data quality control was excellent. When we eventually obtain our risk index for the onset and persistence of depression, we will be able to determine the individual risk of each patient evaluated in primary health car

Discovery of Colossal Breathing-Caloric Effect under Low Applied Pressure in the Hybrid Organic–Inorganic MIL-53(Al) Material

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] In this work, “breathing-caloric” effect is introduced as a new term to define very large thermal changes that arise from the combination of structural changes and gas adsorption processes occurring during breathing transitions. In regard to cooling and heating applications, this innovative caloric effect appears under very low working pressures and in a wide operating temperature range. This phenomenon, whose origin is analyzed in depth, is observed and reported here for the first time in the porous hybrid organic–inorganic MIL-53(Al) material. This MOF compound exhibits colossal thermal changes of ΔS ∼ 311 J K–1 kg–1 and ΔH ∼ 93 kJ kg–1 at room temperature (298 K) and under only 16 bar, pressure which is similar to that of common gas refrigerants at the same operating temperature (for instance, p(CO2) ∼ 64 bar and p(R134a) ∼ 6 bar) and noticeably lower than p > 1000 bar of most solid barocaloric materials. Furthermore, MIL-53(Al) can operate in a very wide temperature range from 333 K down to 254 K, matching the operating requirements of most HVAC systems. Therefore, these findings offer new eco-friendly alternatives to the current refrigeration systems that can be easily adapted to existing technologies and open the door to the innovation of future cooling systems yet to be developed.This work was financially supported by Ministerio de Economía y Competitividad MINECO and EU-FEDER (projects MAT2017-86453-R and PDC2021-121076-I00), Xunta de Galicia and IACOBUS Programme. Funding for open access fee was provided by Universidade da Coruña/CISU

AVALIAÇÃO DE GENÓTIPOS DE GIRASSOL COM BASE EM CARACTERÍSTICAS MORFOAGRONÔMICAS EM AMBIENTES DO CERRADO BRASILEIRO.

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