Search results for "Oleum"
showing 10 items of 150 documents
Total petroleum hydrocarbons (TPH) determination in surfactant stabilized marine water emulsions
2022
Bilge waters are wastewaters produced on boats during navigation and usually contain hydrocarbons and oils. They cannot be released into the sea if not below certain hydrocarbon concentration limits set by current legislation. Surfactants are often used to improve the solubility of petroleum hydrocarbons in water and in this work, the analytical approach proposed is suitable to determine accurately the concentration of hydrocarbons in surfactant-rich waters, as found in bilge water or similar wastewater. The method relies on the surfactant precipitation by addition of potassium and calcium salts, which also promote TPH extraction through a “salting out” effect. This allows for an accurate d…
An open-source instrumentation package for intensive soil hydraulic characterization
2020
International audience; We present a new open-source and modular instrumentation package composed of up to ten automatic in- filtrometers connected to data acquisition systems for automatic recording of multiple infiltration experiments. The infiltrometers are equipped with differential transducers to monitor water level changes in a Mariotte re- servoir, and, in turn, to quantify water infiltration rates. The data acquisition systems consist of low-cost components and operate on the open-source microcontroller platform Arduino. The devices were tested both in the laboratory and on different urban and agricultural soils in France and India. More specifically, we tested three procedures to t…
An Efficient Synthesis of Rubin’s Aldehyde and its Precursor 1,3,5-Tribromo-2,4,6-tris(dichloromethyl)benzene
2011
2,4,6-Tribromobenzene-1,3,5-tricarboxaldehyde (4) can be efficiently prepared in two reaction steps from 1,3,5-tribromobenzene. The intermediate 1,3,5-tribromo-2,4,6-tris(dichloromethyl)benzene (3) crystallizes from petroleum ether in its C3h structure. However, in CDCl3 solution it exists at room temperature in two isomeric forms: 3a (C3h) and 3b (Cs) (1:1.15).The intramolecular Br・・・Cldistances are much smaller than the sum of the van der Waals radii. Therefore, the exocyclic C-C bonds show a hindered rotation.
A reconsideration of the link between vertical externality and managerial incentives
2018
Previous research revealed that the strategic role of delegation contracts disappears if two quantity†setting firms outsource input production to a monopolistic supplier. I show that this role is restored if the assumption of a downstream duopoly is relaxed. Thus, delegation contracts allow downstream profit†maximizing owners to commit their firms to a behavior that differs from their preferences. This behavior varies nonmonotonically with the number of firms in the downstream market. Corresponding deviations from profit maximization are larger if the upstream monopolist makes a price precommitment. But little to no deviation occurs if the number of firms is large.
Upstream Product Market Regulations, ICT, R&D and Productivity
2013
Our study aims at assessing the actual importance of the two main channels usually contemplated in the literature through which upstream sector anticompetitive regulations may impact productivity growth: business investments in R&D and in ICT. We thus precisely try to estimate what are the specific impacts of these two channels and their shares in total impact as against alternative channels of investments in other forms of intangible capital such as improvements in skills, management and organization. For this, we specify an extended production function relating productivity explicitly to R&D and ICT capital as well as to upstream regulations, and two factor demand functions relating R&D a…
Product Line Choice in Retail Duopoly
2011
This paper develops a successive duopoly model to identify conditions under which differentiated retailers that compete in quantities, when deciding on the range of brands to offer, will carry overlapping product lines. They will do so when retail margins on each brand are not too asymmetric. Otherwise, the less profitable brand is foreclosed from the market. It is shown that welfare increases if the upstream industry is perfectly competitive, even though fewer brands may be sold. With price competition though, exclusive dealing arises when retailers are not too differentiated and in-store competition is sufficiently intense.
Contingent reward leader behaviour: Where does it come from?
2010
As many academics have pointed out, while researchers have learned a great deal about the effects of contingent reward (CR) leader behaviour, relatively little is known about its genesis. CR transactional leadership is traditionally viewed as an independent variable which exerts influence downstream. However, if we are to understand how to influence, improve or modify these downstream effects, we need to shift our focus upstream towards the study of transactional leadership as a dependent variable. In line with this reasoning, we put forward the hypothesis that a contextual variable (organizational learning capability) and a subordinate's characteristic (employability) are antecedents of CR…
Stratégie du e-commerçant, accessibilité du produit et logistique urbaine
2013
Several factors impact urban logistics, among them, the recent evolution of e-commerce, by the new flows that it introduces in the city. It seemed interesting to us to understand urban logistics in this way, taking an original point of view, that of the upstream part of the logistics chain, namely the e-commerce strategy. We were thus able to highlight strategic and structural choices having consequences on product accessibility and urban logistics.
The effect of cooperative infrastructure fees on high-speed rail and airline competition
2021
Abstract This paper explores the effects of cooperation between rail and air infrastructures in setting per-passenger fees prior to competition among airlines and high-speed rail (HSR) in a transport network. It is shown that, for a sufficiently low degree of substitution, cooperation results in lower fees and greater HSR traffic than under competition. Besides, it leads to more connecting passengers. An empirical application allows for a quantitative assessment of cooperation. Gains to passengers and operators are sizeable when cooperation either involves all infrastructure managers or the rail and the hub airport managers. Welfare gains are in the range of 10.4–11.1%. Our contribution off…
Interbasin Water Transfers in Spain: Interregional Conflicts and Governance Responses
2014
Semiarid and drought-prone Spain has managed to meet ever-increasing water demands for more than 50 years through the construction of publicly funded hydraulic infrastructure. Interbasin water transfers are the most expensive and complex supply-side tool used. They are also the most controversial, often associated with such unintended consequences as deteriorating freshwater ecosystems, disappearing recreational opportunities provided by aquatic ecosystems, and the loss of development opportunities for downstream communities. This situation has become increasingly unstable over the past decade due to the scarcity of new supply augmentation alternatives, political changes involving European …