Bentonite functionalized with propyl sulfonic acid groups used as catalyst in esterification reactions

AbstractThe main objective of this work is the functionalization of bentonite from the Amazon (region) by the grafting of propyl sulfonic acid groups to catalyze the esterification reaction of acetic acid and 1-propanol. Functionalization was accomplished by anchoring, oxidation and acid activation of (3-mercaptopropyl)trimethoxysilane, (MTPS). The procedure gave acid properties to the raw bentonite. This material, acting as a catalyst, increased the reaction speed and improved the yield by about 12% compared to the uncatalyzed reaction. The functionalized bentonite was characterized by XRD, TG/DTA, FTIR, N2 adsorption/desorption at 77K and XRF, and the surface acidity was determined by titration

Quons Restricted to the Antisymmetric Subspace: Formalism and Applications

In this work we develop a formalism to treat quons restricted to the antisymmetric part of their many-body space. A model in which a system of identical quons interact through a pairing force is then solved within this restriction and the differences between our solution and the usual fermionic model solution are then presented and discussed in detail. Possible connections to physical systems are also considered.Comment: 12 pages, 3 figure

Development of the Platysma Muscle and the Superficial Musculoaponeurotic System (Human Specimens at 8–17 Weeks of Development)

There is controversy regarding the description of the different regions of the face of the superficial musculoaponeurotic system (SMAS) and its relationship with the superficial mimetic muscles. The purpose of this study is to analyze the development of the platysma muscle and the SMAS in human specimens at 8–17 weeks of development using an optical microscope. Furthermore, we propose to study the relationship of the anlage of the SMAS and the neighbouring superficial mimetic muscles. The facial musculature derives from the mesenchyme of the second arch and migrates towards the different regions of the face while forming premuscular laminae. During the 8th week of development, the cervical, infraorbital, mandibular, and temporal laminae are observed to be on the same plane. The platysma muscle derives from the cervical lamina and its mandibular extension enclosing the lower part of the parotid region and the cheek, while the SMAS derives from the upper region. During the period of development analyzed in this study, we have observed no continuity between the anlage of the SMAS and that of the superficial layer of the temporal fascia and the zygomaticus major muscle. Nor have we observed any structure similar to the SMAS in the labial region

Numerical Study of the Thermal Efficiency of a School Building with Complex Topology for Different Orientations

In this work a numerical model that simulates the thermal behavior of a building with complex topology and evaluates the indoor thermal and air quality, in transient conditions, is used for a school building thermal project. The program calculates the building surfaces solar radiation field, the building's temperatures, the internal environmental variables, and the occupant's comfort levels. Initially, after the numerical model is validated, the software is used to evaluate the school building's thermal response for four different orientations, either in winter or summer conditions. The work then aims to identify uncomfortable spaces in order to propose, as an example, several solutions that could be introduced for each orientation, that would improve the thermal comfort and air quality levels to which the occupants are subjected, and decrease the building's energy consumption levels. The information obtained from this study could be used to help a designer choose which thermal systems and solutions function best for a preferred school building orientation

PREFERÊNCIA DE EQÜINOS EM PASTEJO: EFEITO DA ALTURA DE DOSSÉIS DE GRAMÍNEAS DO GÊNERO CYNODON

The experiment was conducted at the experimental farm of the Federal University of Paraná, in February, 1998, and investigated the effect of the different Cynodon grasses structure at the horse grazing. The Cynodon spp. cv Tifton 85, Cynodon nlemfuensis cv Tifton 68, Cynodon spp. cv Tifton 44, Cynodon nlemfuensis (¨Porto Rico¨) and Cynodon nlemfuensis (¨Estrela Roxa¨) grasses were distributed in parcels with 12 m2 in a completely randomized split-plot design with four replications. The parcels were divided in two kinds of patches (tall and short) demonstrated by plants height. Five grazing tests were done with mares, evaluating the number of bites allocated in each treatment. The preference was evaluated by bite number and tiller grazed on each treatment. The bite depth was measured using 20 marked tillers in each experimental unit. The animals showed preference for Tifton 85, followed by Coastcross 1, Tifton 68 and Tifton 44. The star grasses ¨Estrela Roxa¨ and ¨Porto Rico¨ were not preferred. Tifton 85 and Coastcross 1 with more leaves and less stems mass (PO experimento foi conduzido no Centro de Estações Experimentais da Universidade Federal do Paraná, em fevereiro de 1998, quando as gramíneas Cynodon spp. cv Tifton 85, Cynodon nlemfuensis cv Tifton 68, Cynodon spp. cv Tifton 44, Cynodon nlemfuensis (Porto Rico) e Cynodon nlemfuensis (Estrela Roxa) foram estabelecidas em parcelas em um delineamento inteiramente casualizado com parcelas subdivididas e quatro repetições. As parcelas foram subdivididas em duas alturas do dossel (alto e baixo) caracterizadas pela diferença de altura das plantas. Os tratamentos foram ofertados a três éguas por duas horas em cinco dias consecutivos. A preferência entre os tratamentos foi identificada pela avaliação do número de bocados e pela desfolha nas unidades vegetativas marcadas nas parcelas e alturas. A profundidade do bocado foi quantificada por meio da identificação da altura do perfilho estendido e da menor altura pastejada nos perfilhos marcados das diferentes gramíneas. A Tifton 85 foi preferida, seguida pela Coastcross 1, Tifton 68 e Tifton 44. A Estrela Roxa e a Porto Rico foram preteridas. As gramíneas de maior preferência apresentavam maior massa de folhas verdes em relação à massa de colmos (

Search for charginos in e+e- interactions at sqrt(s) = 189 GeV

An update of the searches for charginos and gravitinos is presented, based on a data sample corresponding to the 158 pb^{-1} recorded by the DELPHI detector in 1998, at a centre-of-mass energy of 189 GeV. No evidence for a signal was found. The lower mass limits are 4-5 GeV/c^2 higher than those obtained at a centre-of-mass energy of 183 GeV. The (\mu,M_2) MSSM domain excluded by combining the chargino searches with neutralino searches at the Z resonance implies a limit on the mass of the lightest neutralino which, for a heavy sneutrino, is constrained to be above 31.0 GeV/c^2 for tan(beta) \geq 1.Comment: 22 pages, 8 figure

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results