45 research outputs found
Thermal stabilization of metal matrix nanocomposites by nanocarbon reinforcements
Metal matrix composites reinforced by nanocarbon materials, such as carbon nanotubes or nanodiamonds, are very promising materials for a large number of functional and structural applications. Carbon
nanotubes and nanodiamonds-reinforced metal matrix nanocomposites with different concentrations of
the carbon phase were processed by high-pressure torsion deformation and the evolving nanostructures
were thoroughly analyzed by electron microscopy. Particular emphasis is placed on the thermal stability
of the nanocarbon reinforced metal matrix composites, which is less influenced by the amount of added
nanocarbon reinforcements than by the nanocarbon reinforcement type and its distribution in the metal
matrix
TerrHum: an iPhone app for classifying forest humipedons.
The knowledge of a little number of specific terms is necessary to investigate and describe the forest topsoils: diagnostic components, diagnostic organic and organic-mineral horizons and the 17 series of humus horizons composing all the observed real forest not submerged topsoils. Diagnostic horizons are grouped in humus forms, which represent five humus systems. To become a good topsoil investigator is then only a question of field experience. No mean to do otherwise: you must go in the field with a blade and a good manual and put your hand in the soil. You have to make a hole and to observe on your knee a wall of the pit, from the top to the bottom, detecting all the characters that you find indicated in the manual. At the beginning you will be discouraged, things change from a site to another and never are exactly as in the manual. After few days of difficult survey, you will be able to know your soil even without doing a hole. Be patient and follow what it is indicated in the published first eight articles of Humusica (http://intra.tesaf.unipd.it/people/zanella/hmanual.html). On the poster, you find some examples of diagnostic properties of forest topsoils, and a dichotomy key of classification, you can copy paste and take with you in the field. An iPhone application (Terrhum) allows to bring in the field the necessary information for a fast classification of the topsoil
TerrHum: an iOS application for classifying terrestrial humipedons and some considerations about soil classification
International audienceThe name TerrHum is an abbreviation of the words âTerrestrialâ (not hydromorphic, not submerged) and âHumipedonâ (organic and organic-mineral humus horizons). With this application, it is possible to describe and classify terrestrial forest and grassland topsoils in a system published as a Special Issue entitled âHumusica 1â Terrestrial Natural Humipedonsâ in the journal Applied Soil Ecology. The iOS application TerrHum allows the storage of the main content of Humusica 1 on a cellular phone. Images, diagrams and simplified tables of classification may be recalled with a few touches on the screen. Humus forms, representing five humus systems, are classified based on the vertical arrangement of diagnostic horizons and their attributes. TerrHum allows accessing specific figures that are stored in a virtual cloud and can be downloaded the first time the user recalls them. Once all figures have been opened in the device, the application is ready to use, without any further internet connection. The application is in continuous evolution
A Standardized Morpho-Functional Classification of the Planetâs Humipedons
It was time to take stock. We modified the humipedon classification key published in 2018 to make it easier and more practical. This morpho-functional taxonomy of the topsoil (humipedon) was only available in English; we also translated it into French and Italian. A standardized morphofunctional classification of humipedons (roughly the top 30â40 cm of soil: organic and organomineral surface horizons) would allow for a better understanding of the functioning of the soil ecosystem. This paper provides the founding principles of the classification of humipedon into humus systems and forms. With the recognition of a few diagnostic horizons, all humus systems can be determined. The humus forms that make up these humus systems are revealed by measuring the thicknesses of the diagnostic horizons. In the final part of the article, several figures represent the screenshots of a mobile phone or tablet application that allows for a fast recall of the diagnostic elements of the classification in the field. The article attempts to promote a standardized classification of humipedons for a global and shared management of soil at planet level
A standardized morpho-functional classification of the planetâs humipedons
It was time to take stock. We modified the humipedon classification key published in 2018 to make it easier and more practical. This morpho-functional taxonomy of the topsoil (humipedon) was only available in English; we also translated it into French and Italian. A standardized morphofunctional classification of humipedons (roughly the top 30â40 cm of soil: organic and organomineral surface horizons) would allow for a better understanding of the functioning of the soil ecosystem. This paper provides the founding principles of the classification of humipedon into humus systems and forms. With the recognition of a few diagnostic horizons, all humus systems can be determined. The humus forms that make up these humus systems are revealed by measuring the thicknesses of the diagnostic horizons. In the final part of the article, several figures represent the screenshots of a mobile phone or tablet application that allows for a fast recall of the diagnostic elements of the classification in the field. The article attempts to promote a standardized classification of humipedons for a global and shared management of soil at planet level
Species diversity and litter dynamics in secondary mixed deciduous forest, Thung Salaeng Lung National Park, Northern, Thailand
This study present species composition and potential of litter on carbon and nitrogen return in secondary mixed
deciduous forest after shifting cultivation. The dominant species of trees were Haldina cordifolia, Albizia odoratissima
and Lagerstroemia duperreana. The Important Value Index (IVI) values of trees were 132.91, 17.78 and 14.22,
respectively. The pattern for the decomposition coefficients (k) was highest in the wet period (MayâSeptember) and
lowest in the dry period (OctoberâApril). The carbon and nitrogen return patterns increased in the dry period (Octoberâ
April) and decreased in the wet period (MayâSeptember). Carbon and nitrogen loss in the decomposing litter
continually decreased during the decomposition process from the initial levels, with a final relatively rapid release in
the wet period. Results from this study was understanding of community composition, litterfall production and litter
decomposition for understanding potential of secondary mixed deciduous forest for balancing carbon for mitigating
greenhouse gas effect in the local area
A European Classification of Terrestrial Humus Forms - 1st Approach
A first approach towards an European system gives a general outline on characterisation of the diagnostic horizons and classification of humus forms in aerate conditions (four Mull, three Moder,two Mor humus forms). The question of humus form dynamics in space-time sequences is especially important and taken into account. Other open questions (the relation between the structure of the horizons and pedofauna, fungi and roots, humus forms characterized by dense rooting, by zoogenous and mycogenous influences) are discussed. Some propositions are expounded, according to recent field observations