Search results for "Ash"
showing 10 items of 1718 documents
A Methodology for Protection of Trees Against Lightning Strikes as a Measure to Prevent Fires and Loss of Human Life
2021
Some regions may be characterized by a very low annual lightning ground flash density, and yet lightning strikes seem to have been in those areas the cause of widespread wildfires in forested areas. Due to global climate change, these occurrences seem to be an increasing threat. In this paper, the authors discuss the withstand capability of trees against lightning and introduce the criteria for the deployment of tree lightning protection systems (TLPS) to protect forested areas, where deemed necessary by the tree risk assessment. This work analytically identifies the critical trunk radius of the tree below which the tree may explode in the case of a lightning strike and ignite the surroundi…
Comparison of adsorption properties of commercial silica and rice husk ash (RHA) silica: A study by NIR spectroscopy
2021
Abstract Adsorption properties of Silica gel (commercial silica), rice husk ash (RHA) silica, and their hydrothermally treated products towards water molecules were studied in this work. RHA silica was prepared by heating rice husk to 650°C for 4 h after pretreatment with hydrochloric acid. Portions of the samples of silica were evacuated at 200℃ and then allowed to adsorb water molecules from the surrounding air at either 42 or 50% humidity. The near infrared spectra of these samples were measured at different time intervals during their adsorption of water molecules. The evolved near infrared spectra were analyzed using second derivative techniques. Adsorption properties of these samples …
The effect of ash and compost on the content and bioaccumulation of selected heavy metals
2019
Abstract Therefore the carried out study aimed at determination of the effect of high-calcium brown coal ash and compost being produced from municipal sewage sludge on the content and bioaccumulation of heavy metals in potato tubers, wheat grains and rapeseeds during a three-year period. Rapeseeds contained most Cd whereas wheat rains less. Potato tubers, wheat grains and rapeseeds contained more Mn, Ni and Zn in the fertilization objects with municipal sewage sludge with or without coal ash and compared to those where calcium carbonate or coal ash had been introduced into the soil at a dose corresponding to 1.5 Mg CaO · ha–1 at the beginning of this study. Differences in the Mn, Ni and Zn …
Innovative Recycling of Lime Slaker Grits from Paper-Pulp Industry Reused as Aggregate in Ambient Cured Biomass Fly Ash-Based Geopolymers for Sustain…
2019
Lime slaker grits and biomass fly ash are solid wastes produced by the Kraft paper-pulp industry that are commonly disposed of in landfill. However, recent studies and European regulations discourage such disposal practices. This work investigates an alternative and innovative way to recycle and reuse these wastes in the production of green geopolymeric mortars intended for application in the construction industry. Here, biomass fly ash was used as the main source of alumino-silicate in the binder precursor (70 wt.% substitution to metakaolin), and grits (ranging from 1&ndash
Selection of novel geopolymeric mortars for sustainable construction applications using fuzzy topsis approach
2020
Construction is recognized as one of the most polluting and energy consuming industries worldwide, especially in developing countries. Therefore, Research and Development (R&
"La Bolivie se retire du Cirdi"
2007
International audience
The first catalytic method for Heck alkynylation of unactivated aryl bromides (copper-free Sonogashira) in an ionic liquid: 1 mol-percent palladium/t…
2007
Herein we report the studies of Heck alkynylation (copper-free Sonogashira) with aryl halides (I, Br, Cl) employing various metallic precursors, tertiary phosphanes and bases in [BMIM][BF4] as the solvent. As a result, we provide the first method that allows the coupling of a large array of substrates, either activated or deactivated bromides in an ionic liquid. Furthermore, the system of highest efficiency is unexpectedly the simplest and cheaper combination that employs [Pd(η3-C3H5)Cl]2/PPh3 at only a 1 mol-% loading with pyrrolidine as the base and in the absence of a copper salt. The coupling of sterically and electronically deactivated bromides bearing different functional groups to ar…
El lujo cambiante. El vestido y la difusión de las modas en la Corona de Aragón (siglos XIII-XV)
2015
La apariencia física de las persona era ya en la Baja Edad Media el primer indicativo de su condición social, pero en un período mucho más urbanizado e interconectado que los anteriores, el refinamiento de la indumentaria se convirtió en un hecho con unas connotaciones económicas, políticas y culturales de gran calado. El mismo incremento de la movilidad social llevó además a que no bastara con invertir grandes sumas en la propia imagen, sino que fuera necesario estar atento a los cambios de eso que llamamos “moda”, cuyos orígenes se suelen situar en estos momentos en los que las clases dominantes tradicionales buscaban nuevos elementos de diferenciación frente a los advenedizos. Todo ello …
Socio-emotional Experience in Human Technology Interaction Design – A Fashion Framework Proposal
2021
Technology designers and developers can be understood as social experience (SE) mediators. In user experience (UX), notions of SE have served to identify and define the factors contributing to human-technology interaction (HTI). Three dominant perspectives have been promoted in UX discourse: 1) SE of brand, brand value and consumer culture; 2) technology design as mediator of human-to-human interactions; and 3) meaning generation through action and interaction between actors. Symbolic interactionalism understands meaning as occurring through dialogue, in the construction of the social self, promoting self-reflection as a social construction. This theorisation of social experience is valuabl…
Mākslīgo skropstu pieaudzēšanas ietekme uz acs priekšējo struktūru veselību.
2020
Maģistra darbs ir uzrakstīts 60 lappusēs angļu valodā. Tas satur 23 attēlus, 45 informācijas avotus un 9 pielikumus. Mērķis: šī pētījuma mērķis ir noskaidrot, kādas acu izmaiņas ir notikušas vienu nedēļu pēc daļēji noturīgo skropstu pieaudzēšanas. Metodes: septiņiem pētījuma dalībniekiem tika četras reizes novērtētas konjunktīvas izmaiņas, asaru apjoma izmaiņas un alerģijas rādītājs, izmantojot arī subjektīvas anketas. Rezultāti: visiem šī pētījuma dalībniekiem bija daži ar daļēji noturīgu skropstu pieaudzēšanu saistīti acu simptomi, vairumam dalībnieku bija konjunktīvas apsārtums dažādos līmeņos, un daudziem bija asaru apjoma izmaiņas. Subjektīvi vissatraucošākie simptomi bija sausas/kairi…