Search results for "Oleum"
showing 10 items of 150 documents
River Conservation and Phytodepuration in a Mid-Mediterranean Streambed: A Sicilian Case Study
2016
AbstractFor landslide mitigation purposes, a system of two screen dams was created along the main channel of the Capreria River in Sicily. The de facto constructed wetlands occasioned behind the flow-path barriers produced, for several years, an appreciable reduction of organic load of the upstream municipal wastewaters from the nearby town of Riesi, Italy. This coincidence inspires the prospect of promoting a multifunctional role for these slope-stabilization works, thereby allowing them to be viewed from an intriguing and innovative planning perspective.
Treatment of Oily Wastewater with Membrane Bioreactor Systems
2017
The aim of the present work was to investigate the behavior of a membrane bioreactor (MBR) system for the treatment of oily wastewater. A bench scale MBR was fed with synthetic wastewater containing diesel fuel. Organic carbon, hydrocarbon and ammonium removal, kinetic constants, extracellular polymeric substances production, and membrane fouling rates were monitored. The MBR plant was operated for more than 200 days, and the results highlighted good carbon removal and nitrification, suggesting a sort of biomass adaptation to hydrocarbons. Membrane fouling analysis showed an increase in total resistance, likely due to hydrocarbons, which caused an irreversible fouling (pore blocking) mainly…
Mixture and Distribution of Different Water Qualities: An Experiment on Alternative Scenarios Concerning Vertical Structure in a Complex Market
2001
We set up a model of water management, which is inspired by the possibility of mixing water of different qualities. Water is supplied to two types of consumers with different preferences for water quality and quantity. A distributional knot may exist which optimally distributes the supplied water in the downstream market. Different scenarios compare experimentally the advantages of a centralized versus a decentralized resource management. We conducted experiments with 14 markets in three different settings, labelled as "upstream monopoly", "upstream duopoly" and "duopoly-monopsony". We find that a two-product monopoly performs better than the duopoly regarding social welfare and volatility …
Continuous polymer fractionation of poly(methyl vinyl ether) and a new Kuhn-Mark-Houwink relation
1995
Continuous polymer fractionation (CPF) — a new large-scale method — was applied to the technical poly(methyl vinyl ether) (PVME) using toluence as solvent and petroleum ether as non-solvent. Two different devices served as fractionation apparatus, namely a column packed with glass beads and a set of mixer-settler extractors. Advantages and draw-backs of these devices are discussed. The experiments yielded numerous PVME fractions, varying in molar mass from 22 to 87 kg/mol and in molecular non-uniformity U = (M¯w/Mn) – 1 from 0,25 to 0,41 according to gel-permeation chromatography as compared with ca. U = 1,30 for the starting material. The following Kuhn-Mark-Houwink relation was establishe…
Molecular composition and chemotaxonomic aspects of Eocene amber from the Ameki Formation, Nigeria
2012
The molecular composition of fossil resin from the Eocene Ameki Formation, southern Nigeria has been analyzed by infrared spectroscopy, pyrolysis–gas chromatography–mass spectrometry and thermochemolysis gas chromatography–mass spectrometry to determine the structural class and botanical source of the resin. The pyrolysis products were dominated by bicyclic products derived from regular labdatriene structure and lacked succinic acid indicating Class Ib type amber. The biomarker compositions in the pyrolysates are dominated by sesquiterpenoids of the cadinane and bisabolane classes that are common constituents of higher plants and labdane type diterpenoids. The exclusive presence of labdane …
Outward Foreign Direct Investment by Chinese National Oil Companies
2015
Developed countries have become increasingly suspicious about the rapid growth of Chinese investments in their home countries and abroad, commonly citing potential threats to national security and global governance as the main sources of anxieties. As a result, policy measures in some developed markets have been put in place to create additional regulation and oversight, specifically in highly regulated and strategic industries, such as the oil sector. This article refutes a number of popular myths about Chinese investments in the global oil industry, and suggests a more rigorous dialogue with the Chinese authorities relating to their integration into international institutions.
Underbalance well completion - a modern approach for mature gas fields
2017
The exploitation of natural gas fields from Transylvanian Basin started a century ago. The majority of these fields were discovered and developed in the last century, from 1950 to 1970. So, these reservoirs have over 50 years of production historical. These are mature fields with a very low reservoir pressure. Now, for some of these reservoirs the pressure is 10 – 20 % of initial values. The biggest challenge for a production company is to make completions and recompletions in depleted reservoirs wells. At the beginning was not a problem to do a workover in these wells because the completion fluids were lost in the reservoir and the pressure helped the wells to clean up. Now, because the re…
Computer-aided study of the gas flow within a natural gas storage and the associated collection network
2017
The current paper presents a computer-aided analysis of the way in which a natural gas storage created in a depleted gas deposit and the associated gas collection network are operated, both during the extraction phase and during the injection phase. In a first step, an analysis is carried out on a two-dimensional, nonstationary model for the gas storage, based on the deposit’s geometry and the rock properties, but also on the gas motions. Also, a dynamic simulation of the injection and extraction processes is unfolded, allowing the study and optimisation of elements such as well placement and gas flows through the wells with the goal of maximising the storable gas quantities. A second model…
Bedrock Characterisation of Four Candidate Repository Sites in Finland As Determined by He-Gas Methods
1999
AbstractAt the end of the year 2000, one of four sites will be chosen as the final repository site in Finland. Therefore accurate and comprehensive statistics of the bedrock characteristics such as porosity [% ] and effective diffusion coefficient [m2/s ] of these sites are of importance. Altogether 115 rock samples from the four sites were measured by different He-gas methods to achieve this goal.The results obtained indicate that the average bedrock properties at these sites are quite similar. Variations among individual samples and different rock types within one repository site were larger than variations among the averaged values of the four sites. Some indication of increased microfra…
Upstream Product Market Regulations, ICT, R&D and Productivity
2017
Our study aims to assess the actual importance of the two main channels via which upstream anti-competitive sector regulations are usually considered to impact productivity growth, i.e. by acting as a disincentive to business investments in R&D and in ICT. We estimate the specific impacts of these two channels and their shares in the total impact as opposed to alternative channels of investments in other forms of intangible capital that we cannot explicitly consider for lack of appropriate data such as improvements in skills, management and organization. To achieve this, we specify an extended production function explicitly relating productivity to R&D and ICT capital as well as to upstream…