scholarly journals CHARACTERIZATION OF PAULOWNIA TOMENTOSA STEUD TREES GROWN IN A 5-YEAR-OLD PLANTATION IN COSTA RICA

2021 ◽  
Vol 55 (7-8) ◽  
pp. 743-753
Author(s):  
JOSÉ DAVID SÁNCHEZ-MACHADO ◽  
ROGER MOYA
Keyword(s):  
Costa Rica ◽  
Energy Production ◽  
Calorific Value ◽  
Wood Properties ◽  
Wood Production ◽  
Wood Moisture ◽  
Paulownia Tomentosa ◽  
Green Wood ◽  
Average Wood

Paulownia tomentosa is utilized in Costa Rica and other countries for wood production and as feedstock for biomass, though the variation of wood properties for this species is scarcely known. In this work, the specific wood properties of a 5-year-old plantation in Costa Rica were studied. The results showed that bark and pith percentage and wood specific gravity (SG) increased with tree trunk height, while the proportion of heartwood, green wood density and green wood moisture content decreased. The average wood SG was 0.26 and tended to increase from pith to bark. Low wood SG values are related to low mechanical properties, with the advantage that wood shrinkage is low as well, which gives this wood species the potential to be utilized for reforestation purposes in Costa Rica. The gross calorific value of this species was 17809 kJ/kg, which, together with its cellulose and extractives contents, recommend P. tomentosa as a biomass source for energy production.

Elaboration and Characterization of the Properties of Refractory Cr Base Alloys

2010 ◽  
Vol 72 ◽  
pp. 46-52 ◽  
Author(s):  
Laurent Royer ◽  
Stéphane Mathieu ◽  
Christophe Liebaut ◽  
Pierre Steinmetz
Keyword(s):  
Mechanical Properties ◽  
Melting Point ◽  
Molten Glass ◽  
Energy Production ◽  
Creep Properties ◽  
Refractory Alloys ◽  
Industrial Use ◽  
Kinetics Of ◽  
Selection Of

For energy production and also for the glass industry, finding new refractory alloys which could permit to increase the process temperatures to 1200°C or more is a permanent challenge. Chromium base alloys can be good candidates, considering the melting point of Cr itself, and also its low corrosion rate in molten glass. Two families of alloys have been studied for this purpose, Cr-Mo-W and Cr-Ta-X alloys (X= Mo, Si..). A finer selection of compositions has been done, to optimize their chemical and mechanical properties. Kinetics of HT oxidation by air, of corrosion by molten glass and also creep properties of several alloys have been measured up to 1250°C. The results obtained with the best alloys (Cr-Ta base) give positive indications as regards the possibility of their industrial use.

scholarly journals Scaling in a Geothermal Heat Exchanger at Soultz-Sous-Forêts (Upper Rhine Graben, France): A XRD and SEM-EDS Characterization of Sulfide Precipitates

Geosciences ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 271
Author(s):  
Béatrice A. Ledésert ◽  
Ronan L. Hébert ◽  
Justine Mouchot ◽  
Clio Bosia ◽  
Guillaume Ravier ◽  
...  
Keyword(s):  
Heat Exchanger ◽  
Energy Production ◽  
Electricity Production ◽  
Normal Operation ◽  
Upper Rhine Graben ◽  
Geothermal Heat ◽  
Deep Wells ◽  
Upper Rhine ◽  
Management Issues

The Soultz-Sous-Forêts geothermal site (France) operates three deep wells for electricity production. During operation, scales precipitate within the surface installation as (Ba, Sr) sulfate and (Pb, As, Sb) sulfide types. Scales have an impact on lowering energy production and inducing specific waste management issues. Thus scaling needs to be reduced for which a thorough characterization of the scales has to be performed. The geothermal brine is produced at 160 °C and reinjected at 70 °C during normal operation. In the frame of the H2020 MEET project, a small heat exchanger was tested in order to allow higher energy production, by reinjecting the geothermal fluid at 40 °C. Samples of scales were analyzed by XRD and SEM-EDS, highlighting that mostly galena precipitates and shows various crystal shapes. These shapes can be related to the turbulence of the flow and the speed of crystal growth. Where the flow is turbulent (entrance, water box, exit), crystals grow quickly and mainly show dendritic shape. In the tubes, where the flow is laminar, crystals grow more slowly and some of them are characterized by well-developed faces leading to cubes and derived shapes. The major consequence of the temperature decrease is the increased scaling phenomenon.

Stable isotopic characterization of nitrate wet deposition in the tropical urban atmosphere of Costa Rica

2021 ◽  
Author(s):  
Mario Villalobos-Forbes ◽  
Germain Esquivel-Hernández ◽  
Ricardo Sánchez-Murillo ◽  
Rolando Sánchez-Gutiérrez ◽  
Ioannis Matiatos
Keyword(s):  
Costa Rica ◽  
Wet Deposition ◽  
Urban Atmosphere ◽  
Stable Isotopic ◽  
Isotopic Characterization

Molecular characterization of pseudomonodelphic dagger nematodes of the genus Xiphinema Cobb, 1913 (Nematoda: Longidoridae) in Costa Rica, with notes on Xiphinema setariae Tarjan, 1964

2016 ◽  
Vol 148 (3) ◽  
pp. 739-747 ◽  
Author(s):  
Walter Peraza-Padilla ◽  
Antonio Archidona-Yuste ◽  
Howard Ferris ◽  
Tatiana Zamora-Araya ◽  
Carolina Cantalapiedra-Navarrete ◽  
...  
Keyword(s):  
Costa Rica ◽  
Molecular Characterization

Physico-chemical Characterization of Forest and Agricultural Residues for Energy Conversion Processes

2021 ◽  
Vol 37 (1) ◽  
Author(s):  
Nguyen Hong Nam ◽  
Le Gia Thanh Truc ◽  
Khuong Duy Anh ◽  
Laurent Van De Steene
Keyword(s):  
Energy Conversion ◽  
Chemical Characterization ◽  
Calorific Value ◽  
Forest Residues ◽  
Physico Chemical ◽  
Wide Range ◽  
Biomass Resources ◽  
Thermochemical Processes ◽  
The Difference

Agricultural and forest residues are potential sources of renewable energy in various countries. However, the difference in characteristics of biomass resources presents challenges for energy conversion processes which often require feedstocks that are physically and chemically consistent. This study presented a complete and comprehensive database of characteristics of a wide range of agricultural and forest residues. Moisture, bulk density, calorific value, proximate and elemental compositions, as well as cellulose, hemicellulose, and lignin compositions of a wide range of biomass residues were analyzed. The major impacts of the variability in biomass compositions to biochemical and thermochemical processes were also discussed.

Design and Experimental Characterization of a Swirl-Stabilized Combustor for Low Calorific Value Gaseous Fuels

2021 ◽  
Author(s):  
Simeon Dybe ◽  
Richard Bluemner ◽  
Sebastian Schimek ◽  
Michael Bartlett ◽  
Panagiotis Stathopoulos ◽  
...  
Keyword(s):  
Calorific Value ◽  
Experimental Characterization ◽  
Gaseous Fuels

scholarly journals Evaluation of wood properties from six native species of forest plantations in Costa Rica

2016 ◽  
Vol 37 (1) ◽  
pp. 71-84 ◽  
Author(s):  
Carolina Tenorio ◽  
Róger Moya ◽  
Cynthia Salas ◽  
Alexander Berrocal
Keyword(s):  
Costa Rica ◽  
Native Species ◽  
Wood Properties ◽  
Forest Plantations

scholarly journals Activities That May Influence the Risk of Crocodile (Crocodylus Acutus: Reptilia: Crocodilidae) Attack to Humans in the Tempisque River Area, Guanacaste, Costa Rica.

Uniciencia ◽  
2017 ◽  
Vol 31 (1) ◽  
pp. 13
Author(s):  
Iván Sandoval-Hernández ◽  
Alejandro Duran-Apuy ◽  
Jacqueline Quirós-Valerio
Keyword(s):  
Costa Rica ◽  
Natural History ◽  
Habitat Loss ◽  
Crocodylus Acutus ◽  
Popular Knowledge ◽  
Lack Of Knowledge

One of the largest populations of crocodiles in Costa Rica is located at the Tempisque River. The species is threatened by habitat loss and poaching; but its populations have grown due to the protection given by law. The research was conducted in Guanacaste, Costa Rica. We made a characterization of popular knowledge, activities and perceptions of 374 residents of the study area. It was found that 55% believe that the crocodiles are abundant, 70% believe that populations have increased. The most dangerous activities done are recreation, swimming and fishing. There are significant differences between the proportions of response (X2: 71, n = 10, p <0.0001 X2). These activities are done daily (25%), weekly (30%), monthly (18%) and annually (10%). The risk of attack and the crocodile’s density in the river are not recognized. Also, a lack of knowledge about the natural history and ecology of the species is shown. The reasons for attacks are: the aggressiveness of the animals and their density. There are differences in the responses on the reasons of the attacks (X2: 35, n 8 p <0.0001). Generally, the crocodile perception is unfavorable.

scholarly journals Geophysical characterization of the habitat of Patagioenas fasciata (Columbiformes: Columbidae) in Costa Rica

2016 ◽  
Vol 8 (1) ◽  
pp. 77-84
Author(s):  
Rodrigo Alberto Méndez Solano ◽  
Marlon Salazar Chacón
Keyword(s):  
Costa Rica ◽  
Sea Level ◽  
Thematic Maps ◽  
Migration Routes ◽  
Species Management ◽  
Forested Areas ◽  
Management And Conservation ◽  
Geophysical Characterization

In Costa Rica, Patagioenas fasciata is distributed in forested areas of the highlands, from 900 m above sea level to the top of the ridges. We identified the main habitats of this species with thematic maps in GIS and did a geophysical analysis. The species is found in the highlands of Rincon de la Vieja, SanIgnacio de Acosta and San Vito de Coto Brus. Our information about possible migration routes, altitudes, weather elements and geomorphology of the sites where it moves and lives is relevant to the species’ management and conservation.

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