An experimental burning program took place in maritime pine (Pinus pinaster Ait.) stands in Portugal to increase the understanding of surface fire behaviour under mild weather. The spread rate and ...flame geometry of the forward and backward sections of a line-ignited fire front were measured in 94 plots 10-15 m wide. Measured head fire rate of spread, flame length and Byram's fire intensity varied respectively in the intervals of 0.3-13.9 m min⁻¹, 0.1-4.2 m and 30-3527 kW m⁻¹. Fire behaviour was modelled through an empirical approach. Rate of forward fire spread was described as a function of surface wind speed, terrain slope, moisture content of fine dead surface fuel, and fuel height, while back fire spread rate was correlated with fuel moisture content and cover of understorey vegetation. Flame dimensions were related to Byram's fire intensity but relationships with rate of spread and fine dead surface fuel load and moisture are preferred, particularly for the head fire. The equations are expected to be more reliable when wind speed and slope are less than 8 km h⁻¹ and 15°, and when fuel moisture content is higher than 12%. The results offer a quantitative basis for prescribed fire management.
Cercosporiosis, or brown eye spot, is currently one of the main diseases of the coffee tree. It is caused by
Cercospora coffeicola
Berk. & Cooke. Nevertheless, genetic resistance to this disease has ...not yet been explored in any depth. Our objectives (a) were evaluate the response of 124 accessions from the germplasm collection of the Minas Gerais State (GC), Brazil, and eight commercial cultivars of
C. arabica
to cercosporiosis and (b) determine the best way to perform early progenies selections via controlled greenhouse experiments. Three controlled greenhouse experiments (1–3) were run in different seasons to determine the best way to proceed the selection. The seedlings were inoculated with a four isolates mixture obtained from different regions. The experimental data were analyzed individually (1–3), in a joint analysis, and as repetitions of a randomized complete block design. In each analysis we estimated genetic parameters and E-BLUP (empirical best linear unbiased predictor) genotypic values of the access. There was genetic variability to
C. coffeicola
resistance among the coffee tree accessions germplasm collection. Therefore, genetic improvements could be obtained by selection. Experimental repetitions in different seasons increase the selection efficiency and reliability of resistant genotypes with low cercosporiosis severity. The genotype Sarchimor MG 8840 showed the highest resistance level followed by Guatenano and the Timor Hybrid UFV 377-34, Timor Hybrid UFV 376-14 BE 5, and Wush–Wush × Timor Hybrid UFV 366-08.
Coffee is a crop of great economic importance in many countries. The organic coffee crop stands out from other production systems by aiming to eliminate the use of synthetic fertilizers and ...pesticides. One of the most important limitations in the organic system is the management of diseases, especially coffee rust, which is considered the main disease of this crop. Coffee rust causes a production slump of up to 50%, significantly affecting the profitability of coffee growers. This work aims to review the integrated rust management in organic coffee crop in different producing countries. Regarding the disease management strategies, this review addresses the use of rust-resistant cultivars, cultural management, biological control, use of plant extracts, and chemical rust control by cupric fungicides. Considering the importance of the organic system, the increase in world coffee consumption, and the potential market for this kind of coffee, this review may help researchers and producers looking for alternative strategies to control rust in an organic coffee cultivation system.
We discuss ultracold Fermi gases in two dimensions, which could be realized in a strongly confining one-dimensional optical lattice. We obtain the temperature versus effective interaction phase ...diagram for an s-wave superfluid and show that, below a certain critical temperature Tc, spontaneous vortex-antivortex pairs appear for all coupling strengths. In addition, we show that the evolution from weak-to-strong coupling is smooth, and that the system forms a square vortex-antivortex lattice at a lower critical temperature TM.
Biosorption of copper ions by an industrial algal waste, from agar extraction industry has been studied in a batch system. This biosorbent was compared with the algae
Gelidium itself, which is the ...raw material for agar extraction, and the industrial waste immobilized with polyacrylonitrile (composite material).
The effects of contact time, pH, ionic strength (IS) and temperature on the biosorption process have been studied. Equilibrium data follow both Langmuir and Langmuir–Freundlich models. The parameters of Langmuir equilibrium model were:
q
max
=
33.0
mg
g
−1,
K
L
=
0.015
mg
l
−1;
q
max
=
16.7
mg
g
−1,
K
L
=
0.028
mg
l
−1 and
q
max
=
10.3
mg
g
−1,
K
L
=
0.160
mg
l
−1 respectively for
Gelidium, algal waste and composite material at pH
=
5.3,
T
=
20
°C and IS
=
0.001
M.
Increasing the pH, the number of deprotonated active sites increases and so the uptake capacity of copper ions. In the case of high ionic strengths, the contribution of the electrostatic component to the overall binding decreases, and so the uptake capacity. The temperature has little influence on the uptake capacity principally for low equilibrium copper concentrations. Changes in standard enthalpy, Gibbs energy and entropy during biosorption were determined.
Kinetic data at different solution pH (3, 4 and 5.3) were fitted to pseudo-first-order and pseudo-second-order models.
The adsorptive behaviour of biosorbent particles was modelled using a batch reactor mass transfer kinetic model, which successfully predicts Cu(II) concentration profiles.
•This work explored the supercritical extraction of copaíba (Copaifera sp.) leaves.•The extraction global yield varied from 0.6 to 3.6%.•Martinez's, Sovová’s and Tan and Liou's models fitted well the ...overall extraction curves.•The extracts showed good antioxidant activities.•Copaíba leaves extract has neuroprotective effects against brain ischemia in rats.
Copaíba (Copaifera sp.) is a tree with a wide application in Brazilian folk medicine. The copaíba leaf extract obtained using supercritical CO2 might be applied to afford neuroprotection following experimental stroke. This study aimed to obtain leaf extracts of Copaifera sp. via supercritical fluid extraction, assessing the global yield isotherms, process variables through the kinetic parameters of extraction, as well as antioxidant activity and neuroprotective effects. Three isotherms (40°C, 50°C and 60°C) were studied in the pressure range of 10–30MPa. The overall higher mass on dry basis yield (∼3.8%) and antioxidant activity (∼64%) were observed at 20MPa and 60°C. For the kinetic study of extraction, the extracts obtained with higher and lower antioxidant activity were chosen, and the models of Martinez et al., Tan and Liou and Sovová showed good and similar adjustments, as presented values of residual sum of squares in the order 10−2. The results of histological and immunohistochemical analyzes suggest that the extract obtained at 60°C and 20MPa has anti-inflammatory and neuroprotective effects on experimental stroke induced by microinjections of endothelin-1 (ET-1) into the rat brain.
This study evaluated the yield performance of the tomato hybrids 'DS0060', 'Thaise' and 'Trucker' in the open field and environments protected by agricultural film (F) and polycarbonate panels (P) ...during the Amazonian summer. In the protected environment, the crops produced significantly higher yields than in the open field. 'Thaise' has high thermotolerance and is adaptable to a wide temperature range, making it the best-performing hybrid in environment F. Highest yields were found for 'Thaise' in environment F or P (86.2 and 92.5 t ha-1) together with 'DS0060' and 'Trucker' in environment F (75.3 and 88.2 t ha-1), demonstrating the high yield potential in the interim growing season (January to April). In the open field, the fruit color was paler, fruit flesh firmer and ripening index lower. In environment F, the fruits contained highest levels of soluble solids, lycopene and β-carotene. 'Thaise' contained higher concentrations of these two compounds. Under environment P, the yield of the evaluated tomato hybrids increased considerably, indicating it as a promising possibility for tomato cultivation in tropical regions. 'Thaíse' stood out with high yield and good quality traits, when grown in an F or P environment. These results prove the viability of tomato production as interim crop in tropical regions, under high rainfall and heat, as well as the difference protected environments make for tomato cultivation, in particular the choice of the most suitable cover material for the crop, to ensure high yields coupled with desirable quality properties.
This study evaluates the possibility of adding value to cork granulates, byproducts of cork processing, by using them as biosorbents and precursors of activated carbons. Activation was carried out by ...impregnation with phosphoric acid followed by pyrolysis under N2 flow. Furthermore, biosorbents were treated with a cationic surfactant and activated carbons were subject to a second pyrolysis under propene with the objective of improving hydrophobicity. Physico-chemical, textural, and surface characterization of the materials was carried out employing, among others, N2 adsorption isotherms, Fourier transform infrared (FTIR) spectroscopy, potentiometric titration, temperature programmed desorption (TPD), and immersion calorimetry. Selected samples were tested in the removal of sunflower oil emulsified in water. Activated carbons with higher surface area and lower amount of acidic surface groups showed higher uptake capacity for sunflower oil.
► We proposed a model-based integration. ► A model was implemented to provide management and visualization data for interfaces. ► We validate the model proposed on test case of industry.
Facilitating ...interaction with maintenance systems through intuitive interfaces is a competitive advantage in terms of time and costs for industry. This work presents the CARMMI approach, which aims to integrate information coming from CAx tools, mixed/augmented reality tools and embedded intelligent maintenance systems. CARMMI aims to provide support to operators/technicians during maintenance tasks through mixed reality, providing an easier access, understanding and comprehension of information from different systems. Information about where, when and which data will be presented in interface are defined by CARMMI. The paper presents three test cases that were performed using the proposed concepts and infrastructure. The main benefit of the approach is to provide an extensive and generic model for the integration and management of maintenance data through the use of CARMMI.
The recovery of critical and precious metals from waste electrical and electronic equipment (WEEE) is an environmental and economic imperative. Biosorption has been considered a key technology for ...the selective extraction of gold from hydrometallurgical liquors obtained in the chemical leaching of e-waste. In this work, the potential of tannin resins prepared from Pinus pinaster bark to sequester and recover gold(III) from hydrochloric acid and aqua regia solutions was assessed. Equilibrium isotherms were experimentally determined and maximum adsorption capacities of 343 ± 38 and 270 ± 19 mg g−1 were found for Au uptake from HCl and HCl/HNO3 (3:1 v/v) solutions containing 1.0 mol L−1 H+. Higher levels of acidity (and chloride ligands) significantly impaired the adsorption of gold from both kinds of leaching solutions, especially in the aqua regia system, in which the adsorbent underperformed. Pseudo-first and pseudo-second order models successfully described the kinetic data. The adsorbent presented high selectivity towards gold. Actually, in simulated aqua regia WEEE liquors, Au(III) was extensively adsorbed, compared to Cu(II), Fe(III), Ni(II), Pd(II), and Zn(II). In three adsorption–desorption cycles, the adsorption capacity of the regenerated adsorbent moderately decreased (19%), although the gold elution in acidic thiourea solution had been quite limited. Future research is needed to examine more closely the elution of gold from the exhausted adsorbents. The results obtained in this work show good perspectives as regards the application of pine bark tannin resins for the selective extraction of Au from electronic waste leach liquors.
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