Fine root traits in adult trees of evergreen and deciduous taxa from low and high elevation in the Alps

Based on evidence for herbaceous plants we expected that trees become more efficient in terms of soil exploration by roots and, thus, produce longer and finer roots (higher specific root length, SRL) with increasing elevation. We tested this hypothesis in situ by excavating roots of eight tree taxa, all belonging to genera found frequently in both lowland and high elevation sites. Across three treeline, one montane and four lowland sites from elevations ranging from 320 masl to 2,235 masl, no elevational differences were found in SRL for both broadleaved and conifer tree species. Irrespective of the elevation preference of a species, SRL of evergreen conifers was significantly lower than that of deciduous species. However, there is an increase in total root length for a given 3rd order root diameter with elevation in the broad-leaved taxa. Our findings clearly demonstrate that a high SRL is not an essential attribute of trees growing in a cold high elevation climate in temperate regions, but there is some indication that fine roots get longer as elevation increase

Numerical investigation and static structural analysis of deep groove ball bearings using ANSYS FEA

This paper provides a numerical investigation of material configurations for deep groove ball bearing. The static structural analysis was numerically modelled using ANSYS 18.2 FEA for deep groove 6210 ball bearing. Successful validation was achieved with theoretical and ANSYS values resulting in good agreement. The 6210 ball bearing is numerically investigated by implementing 4 different materials for respective components and a fixed radial load of 1 kN. The effects of total deformation, shear stress, equivalent Von-Mises stress, and equivalent stain are assessed theoretically and numerically. The adoption of different materials resulted in a hybrid ball bearing, achieving lowest total deformation of 5.6 µm, when compared with benchmark model. It was concluded that hybrid ball bearing incorporating different materials for key respective components studied in this work exhibited significant benefits for the application of deep groove ball bearings for electric drives

The snow must go on: Ground ice encasement, snow compaction and absence of snow differently cause soil hypoxia, CO2 accumulation and tree seedling damage in boreal forest

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Relatório de estágio em farmácia comunitária

Relatório de estágio realizado no âmbito do Mestrado Integrado em Ciências Farmacêuticas, apresentado à Faculdade de Farmácia da Universidade de Coimbr

Potential of Near Infrared spectroscopy for classification of different delignificant pre-treatments on banana rachis.

Delignificant pretreatments are fundamental in lignocellulosic materials preprocessing to remove lignin from biomass. Current wet chemical methods are time-consuming, labor-intensive and use hazardous reagents. Near Infrared Spectroscopy (NIRS) provides rapid and non-destructive analysis, and has shown promising results. Spectra collection (8000-4000 cm-1), combined with chemometric analysis based on Cluster Analysis and Principal Component Analysis, has allowed to perform qualitative study of banana rachis, a lignocellulosic residue of agricultural production

Potential of NIR Spectroscopy to classify different delignificant pre-treatments on lignocellulosic biomass: the case study of banana rachis

As crucial step of lignocellulosic materials processing, pretreatments are carried out to break the structure of lignocellulose and make components accessible for further conversions. Today, several delignificant methods have been developed at industrial level (i.e., steam explosion, alkali washing, dilute acid hydrolysis, ammonia fiber explosion, organosolv extraction, wet oxidation), each of them inducing chemical/physical modification on biomass structure, depending on the amount of degraded lignin and on the overall effect on vegetal matrices. NIR Spectroscopy with chemometric analysis based on Cluster Analysis and Principal Component Analysis, has allowed to perform a qualitative study on banana rachis, a lignocellulosic residue of agricultural production, submitted to different delignificant pretreatments. In particular, Organosolv (ethil-acetate, ethanol and acetone) pretreatment, oxidative delignification with sodium hypochlorite, electro-chemically activated (ECA) solution of active chlorine has been carried out, and compared with non-treated banana rachis samples, with the aim to evidenced similarity or differences in sample structures. FT-NIR diffuse reflectance spectra of treated and non-treated rachis samples were collected with a NIRFLex N-500 (Büchi, Switzerland). All the chemometric analyses including math pretreatments, calibration and validation were performed using NIRCal 5.4 (Büchi, Switzerland). Calibration was performed with 66 samples using all data points in the near infrared region from 8,000 to 4000 cm−1, while the remaining 32 were used for blockwise cross validation. Cluster calibrations have permitted to clearly group samples submitted to the different delignificant agents, to different time of treatments and to different combinations of treatments. FT-NIR spectra combined with multivariate cluster analysis has shown to have great potential as an analytical tool for qualitatively characterizing lignocellulosic samples and lay the ground for successive quantitative determinations

Forced air cooled heat sink with uniformly distributed temperature of power electronic modules

The paper discusses an approach to the design of the forced air-cooling heat sink for power electronic application to uniformly distribute the temperature of the semiconductor modules fixed on the top of the heat sink. The proposed approach suggests a minor modification of a conventional fin-based heat sink commonly manufactured for cooling of power electronic modules. Following the proposed modification, an air guide plate having a V-shaped cut is attached to the bottom of the heat sink to redistribute the airflow through the fins. To verify the proposed approach, the modified forced air-cooling system for a power electronic circuit comprising of three IGBT modules was modelled and numerically simulated using Ansys Fluent software under steady-state conditions. The numerical analysis was conducted for a range of power loss 50–100 W in each IGBT module and an airspeed of 5 m/s through the heat sink. The simulation results have shown a good uniform distribution of the temperature across the IGBT modules where the temperature difference does not exceed 0.21 °C

Chemical surprises from an uncultivated sponge symbiont

Piel J, Freeman MF, Gurgui C, et al. Chemical surprises from an uncultivated sponge symbiont. Planta Medica. 2012;78(11):1040-+