Identification of stochastic processes for an estimated icewine temperature hedging variable

Weather derivatives are a relatively new form of financial security that can provide firms with the ability to hedge against the impact of weather related risks to their activities. Participants in the energy industry have employed standardized weather contracts trading on organized exchanges since 1999 and the interest in non-standardized contracts for specialized weather related risks is growing at an increasing rate. The purpose of this paper is to examine the potential use of weather derivatives to hedge against temperature related risks in Canadian ice wine production. Specifically we examine historical data for the Niagara region of the province of Ontario, Canada, the largest icewine producing region of the world, to determine an appropriate underlying variable for the design of an option contact that could be employed by icewine producers. Employing monte carlo simulation we derive a range of benchmark option values based upon varying assumptions regarding the stochastic process for an underlying temperature variable. The results show that such option contracts can provide valuable hedging opportunities for producers, given the historical seasonal temperature variations in the region.wine market, weather derivatives, weather hedging, Agribusiness, Agricultural Finance, Crop Production/Industries, Environmental Economics and Policy, G13, G32, Q14, Q51, Q54,

Erbium environment in glass-ceramics investigated by atom probe tomography

Glass-ceramics (considered here as a glassy host containing crystalline or amorphous nanoparticles) are of interest for luminescent properties as they can combine the sturdiness and low cost of a matrix host with particular spectroscopic behavior that would not appear in this host [1]. Ideally, nanoparticles would fully encapsulate luminescent ions to produce engineered spectroscopic properties. This approach is particularly promising for optical fibers. Indeed, silica is the most common glass used to prepare such waveguides. However, it is necessary to overcome some of its characteristics (high phonon energy, low luminesent ions solubility, ...) which may be detrimental to luminescent properties. As silicate systems have a large phase immiscibility domain when they contain divalent metal oxides (such as Mg), one can take advantage of thermal treatments inherent to the MCVD (Modified Chemical Vapor Deposition) process to obtain nanoparticles through phase separation [2]. By modifying Mg concentration, we have observed modifications of luminescent properties of Er3+ ions [3]. However the question arises of the partition of rare-earth ions in nanoparticles. Qualitative partition of erbium ions in nanoparticles was reported thanks to Secondary Ion Mass Spectrometry analyses [4]. However, the spatial resolution is about the particle size. To go further, we take advantages of recent developments in Atom Probe Tomography (APT) which allowed the extension of such studies to glass-ceramics [5]. Partition of erbium ions is clearly observed in nanoparticles smaller than 10 nm (Figure 1). During this presentation, we will discuss this partition and the most probable nearest neighbors and correlate these results with luminescent properties

Variation de la composition de nanoparticules de 1-10 nm obtenues par séparation de phase dans un verre de silice

National audienceLes verres contenant des nanoparticules ont de nombreuses applications industrielles, notamment grâce à leurs excellentes propriétés thermo-mécaniques [1]. Ils présentent aussi un intérêt pour les propriétés optiques. En effet, l'encapsulation d'ions luminescents (ions de terre rare par exemple) dans des nanoparticules entraînent de nouvelles propriétés de luminescence qui n'existeraient pas dans le verre hôte (bande d'émission élargie, efficacité quantique augmentée, etc) [2]. La préparation de tels verres repose sur des mécanismes de nucléation, croissance et de démixtion dont les premières étapes sont encore assez mal connues. Mais l'avènement de nouvelles techniques de caractérisation à l'échelle nanométrique permet d'améliorer notre compréhension de ces phénomènes. Par exemple, une évolution structurelle des nanoparticules à travers des phases cristallines métastables [3] ou une transformation d'un nucléus amorphe vers une nanoparticule cristalline [4] ont été observées. Des changements de composition ont aussi été rapportés pour des particules de taille 1-10 nm dans des alliages [5] et dans des métaux [6]. Dans cette présentation, nous nous intéressons à la composition de nanoparticules amorphes obtenues par séparation de phase dans un verre de silice. De telles études ont été rendues possibles grâce au développement récent de l'APT (Atom Probe Tomography) pour l'analyse des verres [7]. Nous étudions une fibre optique à base de silice préparée par le procédé MCVD (Modified Chemical Vapor Deposition). Les nanoparticules sont obtenues en incorporant du magnésium qui déclenche une séparation de phase grâce aux traitements thermiques inhérents au procédé MCVD [8]. La composition des nanoparticules dans le verre de silice dopée avec Mg, P, Ge et Er est étudiée dans la gamme 1-10 nm. Nous montrons la partition de Mg, P et Er dans ces nanoparticules ainsi qu'une modification de la composition en fonction de la taille des particules

Alien Registration- Cyr, Lorette (Caribou, Aroostook County)

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Alien Registration- Martin, Catherine (Van Buren, Aroostook County)

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Alien Registration- Cyr, Mary (Allagash, Aroostook County)

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Effets synergiques des voies d'activation des laitiers de hauts-fourneaux (LHF) utilisés dans l'industrie de la préfabrication

Ground granulated blast-furnace slag (GGBS) is a common by-product used for decades in the cement and concrete industry, and having beneficial effects on environmental properties and durability of concretes. However, GGBS reacts less rapidly than cement and the short-term compressive strength of GGBS-concretes are usually lower than the ones of Portland cement concretes. The aim of this paper is to test the efficiency and evaluate the synergic effect of combining different activation routes (fineness of Portland cement and GGBS, use of chemical activation, and application of thermal cycles) on short-term compressive strength of GGBS-Portland cement-based materials. Results showed that the simultaneous use of all activation routes allowed blended cement with GGBS to achieve almost the same initial mechanical characteristics than Portland cement

Studies of Natural and Accelerated Carbonation in Metakaolin-Based Geopolymer

International audienceThe carbonation of Portland-cement-based materials involves the reaction between atmospheric CO 2 and calcium ions in the pore solution. The formation of calcium carbonate is responsible for a decrease in the pH of the pore solution from 12.5 to 9, thus leading to the depassivation of steel reinforcements and their possible corrosion, and can also lead to efflorescence (white crystals formed on the surface). In metakaolin-based geopolymer activated by sodium silicate, in which calcium is almost non-existent, the presence of CO 2 will lead to the formation of sodium carbonates. Since geopolymer can be carbonated, the risk of corrosion or efflorescence needs to be assessed. A pH study of the geopolymer pore solution showed a very fast decrease compared to OPC, with almost total carbonation after only 14 days. In natural atmospheric CO 2 conditions, it was found that the formation of sodium carbonate did not lead to a decrease of the pH to below a value around 9, thus limiting the risk of corrosion by depassivation of reinforcement, but the large amount of carbonate suggested a significant risk of efflorescence. A study of accelerated carbonation performed under an atmosphere of 50% CO 2 highlighted the formation of sodium bicarbonate resulting in a lower pH of the pore solution and a much larger amount of product formed. Finally the study of efflorescence carried out by semi-immersion tests in natural or accelerated conditions confirmed the different nature of the crystals formed (sodium carbonate or bicarbonate) but showed no significant impact on the amount of carbonated products. This study thus demonstrates that the accelerated carbonation test had very limited usefulness, given the rapidity of the natural reaction

Transport Properties of Stripe-Ordered High Tc Cuprates

Transport measurements provide important characterizations of the nature of stripe order in the cuprates. Initial studies of systems such as La(1.6-x)Nd(0.4)Sr(x)CuO(4) demonstrated the strong anisotropy between in-plane and c-axis resistivities, but also suggested that stripe order results in a tendency towards insulating behavior within the planes at low temperature. More recent work on La(2-x)Ba(x)CuO(4) with x=1/8 has revealed the occurrence of quasi-two-dimensional superconductivity that onsets with spin-stripe order. The suppression of three-dimensional superconductivity indicates a frustration of the interlayer Josephson coupling, motivating a proposal that superconductivity and stripe order are intertwined in a pair-density-wave state. Complementary characterizations of the low-energy states near the Fermi level are provided by measurements of the Hall and Nernst effects, each revealing intriguing signatures of stripe correlations and ordering. We review and discuss this work.Comment: 12 pages, 13 figures, brief revie

Mass spectral characterisation of a polar, esterified fraction of an organic extract of an oil sands process water.

RATIONALE: Characterising complex mixtures of organic compounds in polar fractions of heavy petroleum is challenging, but is important for pollution studies and for exploration and production geochemistry. Oil sands process-affected water (OSPW) stored in large tailings ponds by Canadian oil sands industries contains such mixtures. METHODS: A polar OSPW fraction was obtained by silver ion solid-phase extraction with methanol elution. This was examined by numerous methods, including electrospray ionisation (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) and ultra-high-pressure liquid chromatography (uHPLC)/Orbitrap MS, in multiple ionisation and MS/MS modes. Compounds were also synthesised for comparison. RESULTS: The major ESI ionisable compounds detected (+ion mode) were C15-28 SO3 species with 3-7 double bond equivalents (DBE) and C27-28 SO5 species with 5 DBE. ESI-MS/MS collision-induced losses were due to water, methanol, water plus methanol and water plus methyl formate, typical of methyl esters of hydroxy acids. Once the fraction was re-saponified, species originally detected by positive ion MS, could be detected only by negative ion MS, consistent with their assignment as sulphur-containing hydroxy carboxylic acids. The free acid of a keto dibenzothiophene alkanoic acid was added to an unesterified acid extract of OSPW in known concentrations as a putative internal standard, but attempted quantification in this way proved unreliable. CONCLUSIONS: The results suggest the more polar acidic organic SO3 constituents of OSPW include C15-28  S-containing, alicyclic and aromatic hydroxy carboxylic acids. SO5 species are possibly sulphone analogues of these. The origin of such compounds is probably via further biotransformation (hydroxylation) of the related S-containing carboxylic acids identified previously in a less polar OSPW fraction. The environmental risks, corrosivity and oil flow assurance effects should be easier to assess, given that partial structures are now known, although further identification is still needed