Search results for "Vapo"
showing 10 items of 1217 documents
Pampa Biome Environmental Particularities Regarding to Energy Balance
2020
Ecosystem evapotranspiration (ET) has been quantified around the world by different methodologies to understand the energy balance, especially to control the evolution of climate change. It is known that the vegetation of the pampa biome is natural grasslands, it has a large variety of species (flora and fauna), however is it different in the environmental aspects related to the energy balance when compared to the grassland cultivated? In this study the objective was to analyze the environmental differences of the Pampa Biome related to the energy balance in comparison with the pastures cultivated in Barrax, Spain. In the first one the minimum daily ET is 0.99 mm/day, while in the second is…
Volcanic SiO2-cristobalite: A natural product of chemical vapor deposition
2020
Abstract Cristobalite is a low-pressure, high-temperature SiO2 polymorph that occurs as a metastable phase in many geologic settings, including as crystals deposited from vapor within the pores of volcanic rocks. Such vapor-phase cristobalite (VPC) has been inferred to result from silica redistribution by acidic volcanic gases but a precise mechanism for its formation has not been established. We address this by investigating the composition and structure of VPC deposited on plagioclase substrates within a rhyolite lava flow, at the micrometer to nanometer scale. The VPC contains impurities of the form [AlO4/Na+]0—coupled substitution of Al3+ charge-balanced by interstitial Na+—which are ty…
Characterization and modeling of water movement and salts transfer in a semi-arid region of Tunisia (Bou Hajla, Kairouan) – Salinization risk of soil…
2012
Abstract The semi-arid region of Bou Hajla (Kairouan – Central Tunisia) is exposed to the risk of soils and aquifers salinization. A characterization of water movement through the use of TDR probes installed at up to 4 m in depth, and of salts transfer by soil sampling was conducted to highlight this risk. At the same time, climatic parameters were monitored. The results were gathered over the period of approximately 1 year (June 12, 2006 to May 08, 2007). Water infiltration and evaporation, occurred at within distinct materials: two zero flux planes at 1 and 3 m, and a clay-silt layer at 2 m where the soil water content and electrical conductivity is highly varied. Saline profiles show sal…
Evaporite karst in Italy: A review
2017
none 16 si Although outcropping rarely in Italy, evaporite (gypsum and anhydrite) karst has been described in detail since the early 20th century. Gypsum caves are now known from almost all Italian regions, but are mainly localised along the northern border of the Apennine chain (Emilia Romagna and Marche), Calabria, and Sicily, where the major outcrops occur. Recently, important caves have also been discovered in the underground gypsum mines in Piedmont. During the late 80s and 90s several multidisciplinary studies were carried out in many gypsum areas, resulting in a comprehensive overview, promoting further research in these special karst regions. More recent and detailed studies focused…
Reduction-oxidation dynamics of oxidized graphene: Functional group composition dependent path to reduction
2018
Micrometer-sized oxidation patterns containing varying composition of functional groups including epoxy, ether, hydroxyl, carbonyl, carboxyl, were created in chemical vapor deposition grown graphene through scanning probe lithography and pulsed laser two-photon oxidation. The oxidized graphene films were then reduced by a focused x-ray beam. Through in-situ x-ray photoelectron spectroscopy measurement, we found that the path to complete reduction depends critically on the total oxygen coverage and concentration of epoxy and ether groups. Over the threshold concentrations, a complex reduction-oxidation process involving conversion of functional groups of lower binding energy to higher bindin…
Simple soil water balance model (R function)
2022
This R function models the soil water balance (SWB) for two soil layers based on relatively simple assumptions. It is a simple method to calculate actual evapotranspiration, downward water flux (leaching), and upward water flux (or capillary rise) from two soil layers and the net flux between the two soil layers. The necessary input data comprises the change in soil water storage between two time steps per soil layer (e.g. from repeated volumetric soil water content measurements), potential evapotranspiration, precipitation, and the percentage of roots in the top soil layer. The soil water balance model is described in detail in Leimer et al. (2014). It is based on a soil water balance mode…
Demo 54. Pájaro bebedor
2013
Objetivo: Observar el funcionamiento de una máquina térmica sencilla basada en cambios de temperatura y en la evaporación.
Una camera a termoigrometria controllata, a tre celle separabili, per misure di permeabilità al vapore
2002
In questo lavoro è descritta la progettazione e la realizzazione di una nuova apparecchiatura per le misure sperimentali della permeabilità al vapore dei materiali. E’ stato dimensionato, costruito e strumentato un box climatizzato, secondo i requisiti richiesti dalla normativa europea che si occupa di tali sperimentazioni. Tale lavoro vuole rappresentare la pratica attualizzazione, oltre che la continuazione, di una lunga serie di studi affrontati realizzando una prima serie di apparecchiature per le prove di permeabilità al vapore su campioni di legno. Riprendendo questi temi, il lavoro oggetto della seguente tesi di laurea affronta una concreta riprogettazione delle camere climatizzate p…
In situ micro-Raman and X-ray diffraction study of diamonds and petrology of the new ureilite UAE 001 from the United Arab Emirates
2008
International audience; A new olivine-pigeonite ureilite containing abundant diamonds and graphite was found in the United Arab Emirates. This is the first report of a meteorite in this country. The sample is heavily altered, of medium shock level, and has a total weight of 155 g. Bulk rock, olivine (Fo79.8-81.8) and pyroxene (En73.9-75.2, Fs15.5-16.9, Wo8.8-9.5) compositions are typical of ureilites. Olivine rims are reduced with Fo increasing up to Fo96.1-96.8. Metal in these rims is completely altered to Fehydroxide during terrestrial weathering. We studied diamond and graphite using micro-Raman and in situ synchrotron X-ray diffraction. The main diamond Raman band (LO=TO mode at ~1332 c…
Common Misunderstandings of Deterrence Theory in Information Systems Research and Future Research Directions
2022
In the 1980s, information systems (IS) borrowed deterrence theory (DT) from the field of criminology to explain information security behaviors (or intention). Today, DT is among the most commonly used theories in IS security research. Our review of IS research applying DT highlights that many fundamental assumptions of DT are unrecognized and therefore unexamined. This may have resulted in misunderstandings and conceptual confusions regarding some of the basic concepts of DT. For example, some IS studies confuse general deterrence with specific deterrence or do not recognize the difference between the two. Moreover, these fundamental assumptions, when directly examined, may provide importan…