P-x data of (acetic acid + water) at T = (412.6, 443.2, 483.2) K

Experimental p–x data were measured for the (acetic acid + water) system at the temperatures (412.6, 443.2, and 483.2) K between the pressures 196 and 1902 kPa over the entire range of concentrations. Experiments were carried out in static-analytical equipment with quantitative analysis by GC. The experimental data were correlated with the Perturbed-Chain Statistical Associating Fluid Theory considering two association sites for acetic acid and four association sites for water

Evaluation of the Peng–Robinson and the Cubic-Plus-Association equations of state in modeling VLE of carboxylic acids with water

The performance of the classic Peng–Robinson (PR) and the modern Cubic-Plus-Association (CPA) equations of state were evaluated in modeling isobaric and isothermal vapor–liquid equilibria (VLE) of binary mixtures of carboxylic acids (formic, acetic, propanoic or butanoic) + water. Two functionalities of the alpha term were tested in PR, the original term proposed by Soave and the Matthias–Copeman term specially developed for modeling polar compounds. Within the Soave functionality, two generalized forms of the acentric factor were studied, the original general form and the Robinson and Peng modification for values of the acentric factor larger than 0.491. In addition, the case of PR with fitted parameters from saturated properties (as commonly obtained for modern equations of state) was also evaluated. VLE calculations without the use of a binary interaction parameter are in general more accurate with the modern CPA due to the association term; however, when a binary interaction parameter is used, the performance of the PR versions studied here are on average similar to those of CPA, and in some cases even superior. The original alpha function used in the PR equation and the original generalized form of the acentric factor are the best options for modeling organic acids + water systems when the binary interaction parameter is available. Temperature-dependent binary interaction parameters are provided as a database in modeling these complex systems

Vapor Equilibrium Data for the Binary Mixtures of Dimethyl Carbonate and Ethyl Methyl Carbonate in Compressed Carbon Dioxide

Phase equilibrium data for the binary systems of carbon dioxide + dimethyl carbonate and carbon dioxide + ethyl methyl carbonate were obtained. All systems were measured for isotherms ranging from 298.2 K to 328.2 K with pressure ranging between 0.13 MPa and 10.6 MPa. A static equilibrium technique was established with samples quantified using an offline method. The results were modeled using the Peng–Robinson equation of state with van der Waals one-fluid mixing rules

Vapour-liquid equilibrium of propanoic acid+water at 423.2, 453.2 and 483.2K from 1.87 to 19.38bar. Experimental and modelling with PR, CPA, PC-SAFT and PCP-SAFT

Vapour–liquid equilibrium data were measured for the propanoic acid + water system at 423.2, 453.2 and 483.2 K from 1.87 to 19.38 bar over the entire range of concentrations. An experimental apparatus based on the static–analytical method with sampling of both phases was used with quantitative analysis by GC. The system is highly non-ideal showing azeotropic behaviour. The Peng–Robinson (PR), the cubic plus association (CPA), the perturbed chain statistical associating fluid theory (PC-SAFT) and the PC-polar-SAFT (PCP-SAFT) equations of state modelled the data. Two association sites were assumed for both compounds. A single–binary interaction parameter (kij ) was used in all models, and predictive (kij=0) and correlative (View the MathML source) capabilities were assessed. Available data at 313.1, 343.2 and 373.1 K from the open literature were included in the analysis. PCP-SAFT presented higher predictive and correlative capabilities over the entire temperature range. PC-SAFT in predictive mode was not able to represent the azeotropic behaviour but resulted in the second best correlations. CPA presented a satisfactory balance between the two modes. PR predictions were rather poor but correlations were better than those of CPA, at the expense of a larger kij

Recuperación multinivel de procesos de negocio basado en semántica del comportamiento

Retrieving business process (BP) is a fundamental step for reusing software components within new information services and software products. Nevertheless, this step is critical in many fields and it may incur in unnecessary resources consumption due to the complexity to find services matching exactly the user's requirements. Therefore, the development of intuitive, endowed with artificial intelligence and semantics-based methods which can recognize what the user really needs, become an important R&D area because it speeds up the deployment and configuration of new BP. In this context, this book summarizes the results of a scientific research project conduc- ted by Telematics Engineering Group of the University of Cauca (Colombia), in which a BP retrieval environment called BeMantics is defined. This environment is developed through two main modules: a repository module with pre-matching mechanisms based on behavioral semantics; and a structural, semantics and behavioral matching module which uses and error- correcting algorithm to refine the results obtained from repository. As a result the BeMantics environment provides a BP ranking according to their structural, semantics and behavioral similarity with regard to a query BP. This result is later analyzed through a pertinence eva- luation web tool which enables a group of human judges to emit relevance judgments on a set of test BPs. These relevance judgments allow obtaining a subset of BP considered as rele- vant, which let the pertinence tool to be used as basis for studying the relevance of the results achieved with the BeMantics environmen

Recuperación multinivel de procesos de negocio basado en semántica del comportamiento

Retrieving business process (BP) is a fundamental step for reusing software components within new information services and software products. Nevertheless, this step is critical in many fields and it may incur in unnecessary resources consumption due to the complexity to find services matching exactly the user’s requirements. Therefore, the development of intuitive, endowed with artificial intelligence and semantics-based methods which can recognize what the user really needs, become an important R&D area because it speeds up the deployment and configuration of new BP. In this context, this book summarizes the results of a scientific research project conduc- ted by Telematics Engineering Group of the University of Cauca (Colombia), in which a BP retrieval environment called BeMantics is defined. This environment is developed through two main modules: a repository module with pre-matching mechanisms based on behavioral semantics; and a structural, semantics and behavioral matching module which uses and error- correcting algorithm to refine the results obtained from repository. As a result the BeMantics environment provides a BP ranking according to their structural, semantics and behavioral similarity with regard to a query BP. This result is later analyzed through a pertinence eva- luation web tool which enables a group of human judges to emit relevance judgments on a set of test BPs. These relevance judgments allow obtaining a subset of BP considered as rele- vant, which let the pertinence tool to be used as basis for studying the relevance of the results achieved with the BeMantics environment

Black Pastors’ Views on preaching about sex: barriers, facilitators, and opportunities for HIV prevention messaging

Objectives: Despite the disproportionately high rates of heterosexually transmitted HIV infection among US Blacks and ongoing need for effective inexpensive behavioral interventions, the use of sermons as an HIV prevention tool in Black churches has received little research attention. The Black church plays an important role in Black communities and is a potential ally in development and delivery of sexual risk prevention messages. The objective of this study was to examine Black pastors’ thoughts about whether sermons should address issues related to heterosexual relationships–and the barriers and facilitators to discussing these topics in a sermon setting. Design: We conducted in-depth semi-structured, individual interviews among 39 pastors of Black churches in North Carolina and analyzed the interview data using thematic analysis strategies based on grounded theory. Results: Pastors expressed widely ranging opinions, especially about discussion of condom use, but generally agreed that sermons should discuss marriage, abstinence, monogamy, dating, and infidelity–behaviors that impact sexual networks and HIV transmission. The major barriers to incorporation of these subjects into sermons include the extent to which a concept undermines their religious beliefs and uncertainty about how to incorporate it. However, scriptural support for a prevention message and the pastor’s perception that the message is relevant to the congregation facilitate incorporation of related topics into sermons. Conclusions: These findings have implications for the potential utility of sermons as an HIV prevention tool and suggest that it is possible for public health professionals and pastors of Black churches to form partnerships to develop messages that are consonant with pastors’ religious convictions as well as public health recommendations

Measurement of the Transverse-Longitudinal Cross Sections in the p (e,e'p)pi0 Reaction in the Delta Region

Accurate measurements of the p(e,e?p)pi0 reaction were performed at Q^2=0.127(GeV/c)^2 in the Delta resonance energy region. The experiments at the MIT-Bates Linear Accelerator used an 820 MeV polarized electron beam with the out of plane magnetic spectrometer system (OOPS). In this paper we report the first simultaneous determination of both the TL and TL? (``fifth" or polarized) cross sections at low Q^{2} where the pion cloud contribution dominates the quadrupole amplitudes (E2 and C2). The real and imaginary parts of the transverse-longitudinal cross section provide both a sensitive determination of the Coulomb quadrupole amplitude and a test of reaction calculations. Comparisons with model calculations are presented. The empirical MAID calculation gives the best overall agreement with this accurate data. The parameters of this model for the values of the resonant multipoles are |M_{1+}(I=3/2)|= (40.9 \pm 0.3)10^{-3}/m_pi, CMR= C2/M1= -6.5 \pm 0.3%, EMR=E2/M1=-2.2 \pm 0.9%, where the errors are due to the experimental uncertainties.Comment: 10 pages, 3 figures, minor corrections and addition

Magnetism in Herbig Ae/Be stars and the link to the Ap/Bp stars

Among the A/B stars, about 5% host large-scale organised magnetic fields. These magnetic stars show also abundance anomalies in their spectra, and are therefore called the magnetic Ap/Bp stars. Most of these stars are also slow rotators compared to the normal A and B stars. Today, one of the greatest challenges concerning the Ap/Bp stars is to understand the origin of their slow rotation and their magnetic fields. The favoured hypothesis for the latter is that the fields are fosils, which implies that the magnetic fields subsist throughout the different evolutionary phases, and in particular during the pre-main sequence phase. The existence of magnetic fields at the pre-main sequence phase is also required to explain the slow rotation of Ap/Bp stars. During the last 3 years we performed a spectropolarimetric survey of the Herbig Ae/Be stars in the field and in young clusters, in order to investigate their magnetism and rotation. These investigations have resulted in the detection and/or confirmation of magnetic fields in 8 Herbig Ae/Be stars, ranging in mass from 2 to nearly 15 solar masses. In this paper I will present the results of our survey, as well as their implications for the origin and evolution of the magnetic fields and rotation of the A and B stars.Comment: To appear in the proceedings of "Ecole d'astronomie du CNRS et du PNPS : Les champs magnetiques stellaires", editors: C. Neiner and J.-P. Zahn, EAS Publications Serie