The zwitterion 1-butylimidazolium-3- (n-butanesulfonate)

The mol&shy;ecule of the title compound, C11H20N2O3S, contains a positively charged imidazolium head group and a negatively charged sulfonate tethered together by a four-carbon chain. There is weak intermolecular hydrogen bonding within the structure between the sulfonate O atoms and the H atoms of the imidazolium ring. The sulfonate group causes a twisting of the butyl chain and a decrease in the dihedral angle between the second and third carbon chain compared to the unsubstituted butyl group.<br /

Photo- and solvatochromic properties of nitrobenzospiropyran in ionic liquids containing the [NTf2]- anion

The photo-, thermo- and solvatochromic properties of 2,3-dihydro-10,30,30-trimethyl-6-nitrospiro- [1-benzopyran-2,20-1H-indole] (BSP-NO2) were studied in ILs containing the anion [NTf2]- by UV-Vis absorption spectroscopy, ab initio molecular orbital theory and density functional theory (DFT) calculations. It was found that the kinetics and thermodynamics of the BSP-NO2 MC (merocyanine) equilibrium was sensitive to the nature of the cation. It was also observed that the imidazolium cation can form a through-space orbital interaction with the MC isomer, rather than a simple electrostatic interaction, thus preventing the MC conversion back to the BSP-NO2 isomer. The BSP-NO2 MC equilibrium thus serves as a model system for studying modes of interaction of the cations in ionic liquids

Electrochemical method for studying localized corrosion beneath disbonded coatings under cathodic protection

This paper presents a new method for measuring localized corrosion under disbonded coatings by means of an electrochemical sensor, denoted differential aeration sensor (DAS). It measures the distribution of electrochemical currents over an electrode array surface partially covered by a crevice that simulates a disbonded coating. The DAS has been evaluated using immersion tests at open circuit and under cathodic protection (CP) conditions. Under both conditions, anodic as well as cathodic current densities were detected within the crevice. A fundamental understanding for the detection of anodic currents under CP has been explained in terms of basic electrochemistry. Based on the current distribution data provided by the sensor, two different analysis methods have been used to estimate corrosion and its distribution. These methods consisted of a direct application of Faraday\u27s Law to the anodic currents detected by the array, and on a sensor-specific method denoted corrected currents\u27 method. It has been demonstrated that under diffusion controlled conditions this latter method produces a better corrosion estimation than the direct application of Faraday\u27s Law. The corrected currents\u27 method allowed the estimation of corrosion patterns outside the crevice under CP. Good correlation between electrochemical calculations and surface profilometry results has been obtained

N-methyl-N-alkylpyrrolidinium nonafluoro-1-butanesulfonate salts : Ionic liquid properties and plastic crystal behaviour

A series of N-methyl-N-alkylpyrrolidinium nonafluoro-1-butanesulfonate salts were synthesised and characterised. The thermophysical characteristics of this family of salts have been investigated with respect to potential use as ionic liquids and solid electrolytes. N-Methyl-N-butylpyrrolidinium nonafluoro-1-butanesulfonate (p1,4NfO) has the lowest melting point of the family, at 94 &deg;C. Electrochemical analysis of p1,4 NfO in the liquid state shows an electrochemical window of ~6 V. All compounds exhibit one or more solid&ndash;solid transitions at sub-ambient temperatures, indicating the existence of plastic crystal phases.<br /

Control of biodegradation of a Mg alloy in simulated body fluid

Mg alloy AZ31 is an attractive candidate for coronary artery stents, as it possesses excellent biocompatibility in human body and good mechanical properties. However, AZ31 magnesium alloys generally have poor corrosion resistance in the body environment. This paper reports on the early stages of an investigation into the corrosion mechanism and the morphology of corrosion of AZ31 in simulated body fluid (SBF). The investigation will also consider ways of improving corrosion resistance of this alloy in SBF through the use of ionic liquids. The results to date have shown that AZ31 suffers severe localized pitting corrosion in SBF. The pits mainly develop adjacent to the Al-Mn intermetallic second phase in the &alpha; matrix. Energy Dispersive X-Ray Spectroscopy results revealed the presence of Mg, O, Ca, and P in the layer of corrosion product. Treatment of the AZ31 alloy prior to corrosion testing in SBF with the ionic liquid trimethyl (butyl) phosphonium diphenyl phosphate (P1444DPP) produced some increase in the corrosion resistance of the alloy

Deconstructing the policyscape for reducing deforestation in the Eastern Amazon: practical insights for a landscape approach

In international debates on climate change mitigation and forests, there is increased recognition of the importance of a landscape approach to effectively address tropical deforestation. Such an approach, although increasingly promoted, remains only loosely defined and requires further development in order to effectively integrate different interventions at landscape level. In particular, it is important to understand the possible interactions between different landscape interventions at local level—where they are intended to have effect—and the challenges associated with them. Inspired by the complexity of policy mix analysis, this article seeks to shed light on these interactions by analysing how different policies and measures for reducing deforestation and degradation have played out in a jurisdiction with wide-ranging actors and interventions aimed at shaping their behaviour. Focusing on smallholders, we examine the Sustainable Landscapes Pilot Programme in São Félix do Xingu, looking at how different policies interact—categorising interactions as “complementary,” “mutually reinforcing” (synergistic), “in conflict,” “interdependent,” and/or “redundant”—and explain how proponents of this pilot programme seek to integrate them. Most analysis is based on primary data collected through quantitative (i.e., random stratified sampling and surveys) and qualitative (i.e., observation and focus groups) methods. The São Félix do Xingu case shows that understanding effects of different policies and measures on people's behaviour requires a deeper look at local perceptions and reactions to such policies and measures, something most studies on the topic have overlooked. Ultimately, the heterogeneity and complexity of social practices that permeate landscapes must be recognised in order to integrate diverse measures to reduce deforestation