Search results for "Oleum"
showing 10 items of 150 documents
Monthly Hydrological Indicators to Assess Possible Alterations on Rivers’ Flow Regime
2018
Assessing potential deviations of the fundamental river basins’ hydrological processes and streamflow characteristics from the “natural trajectory” represents a high-priority objective to understand the biological impact of altered flow regime on river ecosystems. Existing approaches are mainly based on the analysis of daily-based indicators of hydrologic alteration, which requires wide database, including “pre-impact” and “post-impact” daily flow data frequently unavailable. The hydrological modeling is commonly used to face data missing problems or reconstruct natural conditions, even if models, especially at the daily scales, are often complex and computationally intensive. The use of si…
Trans-boundary land cover changes and its influences on water crisis: Case study of the Aras River
2020
Abstract In a watershed, disturbing land covers (LCs) are one of the most important factors in the balance and flow rate of water. This study aimed to monitor and model LC changes in the upstream of the Aras River Basin in Turkey over 1984, 2002, 2010 and 2016. The main ground to conduct such an analysis was to mitigate severe economic, social and ecological consequences driven by agricultural activities and dam construction along with probable climate change, which would decrease the water flow from the Aras River to Caspian Sea. The study approach consisted of four main steps: 1) producing LC maps using Landsat satellite images, 2) performing the change analysis, 3) identifying the change…
Design and Analysis of Electric Powertrains for Offshore Drilling Applications
2016
Doktorgradsavhandling ved Institutt for ingeniørvitenskap, Universitetet i Agder, 2016 The global energy market is challenged with an ever increasing need for resources to meet the growing demands for electric power, transportation fuels, etc. Although we witness the expansion of the renewable energy industry, it is still the fossil fuels, with oil and gas dominating the scene of global energy supply sector, that provide majority of worldwide power generation.However, many of the easily accessible hydrocarbon reserves are depleted which requires from the producers of drilling equipment to focus on cost-effective operations and technology to compete in a challenging market. Particularly high…
The Norwegian eHealth Platform: Development Through Cultivation Strategies and Incremental Changes
2017
This chapter describes the conceptualization process, early stage development, and incremental changes in the creation of the Norwegian eHealth platform for patient-oriented services. The platform was launched in 2011 as an information-oriented portal and gradually developed into a complex platform enabling several eHealth services. Some of these services required the linking and reuse of existing components and resources, while other required the creation of novel parts. Overall the process has been driven by strong political will and visions towards making health services more accessible to informed patients. In this chapter we examine this effort as a process of cultivation of the instal…
Metallic nanoparticle enrichment at low temperature, shallow CO2 seeps in Southern Italy
2012
We report on metal enrichment along a natural pH gradient owing to increased CO2 degassing at cold, shallow seeps of Vulcano Island in the Mediterranean Sea, off Sicily. We assessed composition of unfiltered and filtered seawater (<100 nm) along acidic zones ranging between ambient and pH 5, and showed that most seep derived elements are present as nanoclusters which then aggregate into larger colloids while mixing with ambient seawater along a pH gradient. Size and elemental composition of such naturally occurring nanoparticles assessed by modern characterisation methods were in good agreement with the results from conventional analytical methods. We provide analytical evidence for the pre…
Performance and combustion analysis of a supercharged double-fuel spark ignition engine
2019
In order to increase fuel economy and reduce pollutant emissions in the last decades light duty spark ignition (SI) engines have become smaller, supercharged and equipped with direct injection. A suitable alternative to oil derived fuel is represented by gaseous fuels, such as Natural Gas (NG) and Liquefied Petroleum Gas (LPG), whose higher knock resistance and better mixing capabilities substantially improve vehicle fuel economy and pollutant emissions. The simultaneous combustion of gasoline and gaseous fuel (Double-Fuel operation, DF) in a naturally aspirated SI engine has already been investigated in the past also by the same authors, proving remarkable results in terms of engine effici…
Innovation by co-evolution in natural resource industries: The Norwegian experience
2011
Author's version of an article published in the journal: Geoforum. Also avaliable from the publisher at: http://dx.doi.org/10.1016/j.geoforum.2011.01.008 Some resource-based economies become wealthy while others stay poor and Norway belongs to the first category. This paper argues that part of the answer to why Norway has managed to benefit from its rich natural resources is found in the formation of a well-functioning national innovation system. The paper integrates the innovation system approach with a historical approach through the concept of co-evolution. The empirical study investigates how innovation systems evolve in natural resource industries through analysing the co-evolution bet…
Terpenoid composition and chemotaxonomic aspects of Miocene amber from the Koroglu Mountains, Turkey
2014
Abstract A recently discovered fossil resin from Koroglu Mountain in Turkey has been analyzed by gas chromatography–mass spectrometry and pyrolysis gas chromatography–mass spectrometry to determine its structural class and botanical origin. The sesqui- and diterpenoids contained in the amber extract were used as chemosystematic markers when compared with terpenoids in extant conifers. The pyrolysis products were dominated by labdanoid derived bicyclic products together with succinic acid indicating Class Ia type amber. The biomarker compositions of the resin comprise mainly sesqui- and diterpenoids, and lack triterpenoids. This distribution suggests a gymnosperm, and more specifically a con…
Characterization of petroleum-based products by infrared spectroscopy and chemometrics
2012
Abstract The role of fossil fuels in providing the energy required for automobiles, factories and daily life has seriously concerned the authorities. Consistency of the quality of petroleum-based products is an important aspect of social and environmental criteria in a developed society. High-quality petroleum-based fuels would have several benefits (e.g., reduction in rate of consumption, less environmental pollution and durability of hardware). We review recent advances in the application of infrared spectroscopy in the petroleum industry. We focus on the methods proposed for the determination of a wide range of characteristics in petroleum-based products. We discuss methods based on the …
Calibration of a knock prediction model for the combustion of gasoline-LPG mixtures in spark ignition engines
2015
Gaseous fuels, such as liquefied petroleum gas (LPG) and natural gas (NG), thanks to their good mixing capabilities, allow complete and cleaner combustion than gasoline in spark ignition (SI) engines, resulting in lower pollutant emissions and particulate matter. In a previous work the authors showed that the simultaneous combustion of gasoline and LPG improves an SI engine efficiency with respect to pure gasoline operation with any significant power loss. The addition of LPG to the gasoline-air mixture produces an increase in knock resistance that allows running the engine at full load with overall stoichiometric mixture and better spark advance. In order to predict both performance and ef…