Biodiesel production through esterification using ionic liquids as catalysts

There is a growing interest in the development of alternative technologies to the oil economy, based on renewable energy sources. Biodiesel is an alternative fuel that can be produced from a wide range of raw materials such as vegetable oils and animal fats. Yet, the use of sources that do not compete with the food market, such as waste cooking oils - which usually feature high levels of free fatty acids (FFA’s) -, can lead to problems in the process of biodiesel production through alkaline transesterification. Ionic liquids (ILs) could be employed in the biodiesel production to partially overcome these problems; since they are able to catalyze the esterification reaction of FFA’s to biodiesel (FAMEs) as well as the transesterification reaction of triglycerides. Ionic liquids are also viable due to the fact that they can be easily recovered and recycled, decreasing their cost. Experimental results concerning the recyclability of the ionic liquid 1-butyl-3-methylimidazolium hydrogen sulfate [BMIM][HSO4] and its influence on the conversion of organic acids to biodiesel and the content of FAMEs will be presentedinfo:eu-repo/semantics/publishedVersio

Vector Meson Dominance as the first order of a sequence of Pade Approximants

The use of Pade Approximants for the analysis of the pion vector form-factor is discussed and justified in this talk. The method is tested first in a theoretical model and applied then on real experimental data. It is shown how the Pade Approximants provide a convenient and reliable framework to incorporate both low and high energy information in the euclidean region, leading to improved determinations of the low energy parameters such as, e.g., the quadratic radius ^pi_V.Comment: 4 pages, 3 figures, espcrc2 style. To appear in the proceedings of the 14th International QCD Conference, QCD 08, 7-12 July 2008, Montpellier (France

Biodiesel production through esterification using ionic liquids as catalysts

There is a growing interest in the development of alternative technologies to the oil economy, based on renewable energy sources. A possible solution is a biofuel usable in compression-ignition engines, produced from biomass rich in fats and oils. Biodiesel is an alternative fuel that can be produced from a wide range of raw materials such as vegetable oils and animal fats. Yet, the use of sources that do not compete with the food market, like waste cooking oils - which usually feature high levels of free fatty acids (FFA’s) -, can lead to problems in the process of biodiesel production through alkaline transesterification. Ionic liquids (ILs) could be employed in the biodiesel production to partially overcome these problems; since they are able to catalyze the esterification reaction of FFA’s to biodiesel. In this work, experimental results will be presented concerning the study of the influence of ILs in the catalysis of esterification reactions of organic acids to the corresponding methyl esters. Different imidazolium-based ILs were tested for biodiesel production through an esterification reaction of oleic acid, using a previously optimized reaction methodology [1]: 1-butyl-3-methylimidazolium hydrogen sulfate ([BMIM][HSO4]), 1-butyl-3-methylimidazolium methanesulfonate, 1-butyl-3-methylimidazolium methyl sulfate, 1-metylimidazolium hydrogen sulfate ([HMIM][HSO4]) and tributylmethylammonium methylsulfate. The experimental values obtained for the conversion of the oleic acid through an esterification reaction showed that the ionic liquid ([BMIM][HSO4]) would be one of the most promising catalysts. The recovery of the selected [BMIM][HSO4] ionic liquid was studied for different catalyst loading: 10, 15 and 20 wt% - relative to the mass of oleic acid. The reaction yield was determined by acidity using a titrimetric method (EN 14104). The composition characterization of the biodiesel samples (identification of fatty acid methyl esters) was evaluated by gas chromatography with FID detector (EN 14103). The obtained results confirm that it is possible to reuse [BMIM][HSO4] ionic liquid in successive reactions without great loss of yield and, thereafter, to significantly reduce the costs associated with the use of ILs as catalysts. Moreover, the esterification reaction with the [HMIM][HSO4] IL was also studied and further comparison of the methyl esters content obtained with each catalyst will be possible.info:eu-repo/semantics/publishedVersio

Light-Front Model of Transition Form-Factors in Heavy Meson Decay

Electroweak transition form factors of heavy meson decays are important ingredients in the extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements from experimental data. In this work, within a light-front framework, we calculate electroweak transition form factor for the semileptonic decay of $D$ mesons into a pion or a kaon. The model results underestimate in both cases the new data of CLEO for the larger momentum transfers accessible in the experiment. We discuss possible reasons for that in order to improve the model.Comment: Paper with 5 pages and 2 eps figures. To appear to Nuclear Physics B. Talk at Light Cone 2009: Relativistic Hadronic and Particle Physics (LC 2009), Sao Jose dos Campos, S.P, Brazil, 8-13 Jul 2009

Space- and time-like electromagnetic pion form factors in light-cone pQCD

We present a combined analysis of the space- and time-like electromagnetic pion form factors in light-cone perturbative QCD with transverse momentum dependence and Sudakov suppression. Including the non-perturbative ``soft' QCD and power suppressed twist-3 corrections to the standard twist-2 perturbative QCD result, the experimental pion data available at moderate energies/momentum transfers can be explained reasonably well. This may help towards resolving the bulk of the existing discrepancy between the space- and time-like experimental data.Comment: 14 pages, 3 figure

Emergency and Scheduled Respite Care for Caregivers of Persons with Dementia: A Proposed Program

Introduction: Respite care is defined as providing the primary caregiver with relief or a reprieve from care commitments on a short-term or emergency basis. Despite a demonstrated interest in and need for respite care programs, our research has shown that scarce resources exist via a statewide dementia respite program administered by Vermont’s five Area Agencies on Aging. Grants are small and many families do not fall within the eligibility requirements. In FY2010, only 290 families across the state met eligibility requirements (physicians’ diagnosis of dementia, income less than 300% of poverty line, unpaid caregiver, primary residence in VT) and were awarded limited funding for the provision of outside care (up to $750.00 each). For many of these families, this money is typically used to provide substitute care when the primary caregiver is not available. To date, there is no true emergency respite program in place for caregivers. This has placed a strain on families and day facilities, particularly when situations arise in which a caregiver is unable to pick up their family member due to an emergency situation. Our goal was to demonstrate the feasibility of a respite program to address this need.https://scholarworks.uvm.edu/comphp_gallery/1061/thumbnail.jp

Dissensus in post-2012 Russian art: self-perceptions vis-à-vis the West

This research looks into the dissensus in post-2012 Russian art, particularly music and performance art. The goal of the study is twofold. First it attempts to reveal the main Russian identity patterns as presented by the non-conformist artists. Second, it tries to reveal how these artists depict the Russian identity in regard to the West. To that end, the thesis employs the concept of dissensus introduced by Jacques Rancière (2010), which is the indirect dispute with the established framework of the consensus or the hegemonic discourse defining what is taken for granted and viewed as ‘the proper’. The selected sample of artworks is analysed using the Making Identity Count inductive discourse analysis method to recover the relatively stable national identity discourses. Nevertheless, this research uses it as an efficient tool for revealing the identity patterns that guide the meaning creation process of the selected dissident artists. The main conclusions of the research are as follows. The dissensus in post- 2012 contemporary Russian art deconstructs the hegemonic identity patterns opening opportunities for potential new identifications. The research also shows that the West – Russia identity dichotomy is not relevant as depicted in the selected sample of artworks. Moreover, among the selected dissident artists this dichotomy is subjected to constructive criticism.https://www.ester.ee/record=b5439227*es

RQM description of the charge form factor of the pion and its asymptotic behavior

The pion charge and scalar form factors, $F_1(Q^2)$ and $F_0(Q^2)$, are first calculated in different forms of relativistic quantum mechanics. This is done using the solution of a mass operator that contains both confinement and one-gluon-exchange interactions. Results of calculations, based on a one-body current, are compared to experiment for the first one. As it could be expected, those point-form, and instant and front-form ones in a parallel momentum configuration fail to reproduce experiment. The other results corresponding to a perpendicular momentum configuration (instant form in the Breit frame and front form with $q^+=0$) do much better. The comparison of charge and scalar form factors shows that the spin-1/2 nature of the constituents plays an important role. Taking into account that only the last set of results represents a reasonable basis for improving the description of the charge form factor, this one is then discussed with regard to the asymptotic QCD-power-law behavior $Q^{-2}$. The contribution of two-body currents in achieving the right power law is considered while the scalar form factor, $F_0(Q^2)$, is shown to have the right power-law behavior in any case. The low-$Q^2$ behavior of the charge form factor and the pion-decay constant are also discussed.}Comment: 30 pages, 10 figure