Atmospheric-Pressure Non-thermal Plasma-JET effects on PS and PE surfaces

https://www.scopus.com/inward/record.url?eid=2-s2.0-84938125206&partnerID=40&md5=c2325a28f944e7e3e20b601b8d9a73efThe Atmospheric-Pressure Non-Thermal Plasma (APNTP) has become a topic of a great interest for a wide spectrum of applications in different industry branches, including the surface of treatment processes. In this work we evaluate the effect of an argon APNTP exposure to determine changes suffered by a polystyrene (PS) and polyethylene (PE) polymer surface through RAMAN spectroscopy and SEM. It was determined that the hydrophilic change in energetic terms, i.e. surface activation in the PS and PE polymers is addition of oxygen by surface activation when the samples with jet plasma are exposed with the inert argon gas. It was possible to characterize the hydrophilic shift based on the change in intensity of the spectra. © Published under licence by IOP Publishing Ltd.Ad Astra Rocket Company,Instituto Tecnologico de Costa Rica,International Atomic Energy Agency (IAEA),Universidad Nacional de Costa Ric

Paisajes urbanos híbridos-dispersos: tecnovación en gestión urbana sostenible

El creciente proceso de dispersión territorial de las ciudades latinoamericanas y venezolanas (Maracaibo), deriva de la expansión incontrolada de la periferia urbana por ausencia o trasgresión de las restricciones físico-geográficas y legales y es consecuencia de la migración, el laissez faire territorial, la poca capacidad de gestión y la ausencia de cultura de sostenibilidad. Resulta de formas de producción del hábitat -paisajes urbanos híbridos-dispersos, donde coexisten y se mezclan en un continuo espaciotemporal desarticulado, fragmentos urbanos con diferentes códigos genéticos (urbanización espontánea y planificada). Este patrón de ocupación y desarrollo urbano, basado en tipologías extensivas de bajo rendimiento-intensidad de uso, genera fuertes presiones frente a las que parece no existir capacidad de respuesta institucional o a las que muchas veces no se quiere responder por razones políticas e ideológicas. La dispersión urbana en Maracaibo se ha traducido en el aumento de los costos de urbanización, del incremento del déficit de los servicios infraestructurales, de las asimetrías en la distribución espacial de calidad de vida y la precariedad. Este modelo disperso-insostenible que caracteriza a Maracaibo - con 1,6 millones de habitantes - ha desbordado los límites de la ciudad, ocupando los bordes de los corredores urbanos metropolitanos que desde la ciudad atraviesan la Zona Protectora (ZP). La ZP es un green belt plurimunicipal de 20.800 Has, que bordea y define el limitefrontera urbana del Archipiélago Metropolitano de Maracaibo (AMM). La ZP fue decretada en 1989 por el Ministerio del Ambiente (MARN) para frenar la expansión anárquica de Maracaibo y actuar como agente regulador del clima y el medio ambiente en beneficio de la calidad de la vida urbana y como políticacontenedor del crecimiento urbano de la ciudad, actualmente en proceso de ocupación por rituales urbanos en expansión. La ponencia presenta la metodología -estrategia de planificación-evaluación innovadora- (EPE+i) y resultados de un Estudio realizado para el Ministerio del Ambiente, con el fin de decidir sobre la desafectación total o parcial de la ZP. Con ese propósito se evalúa el impacto de los posibles futuros escenarios de ocupación urbana de la ZP, en la sostenibilidad del AMM. La EPE+i llena el vacío de la planificación-gestión urbana en Venezuela, asumiendo el principio de sostenibilidad y trenzando estratégicamente el proceso de Planificación-Gestión Urbana (PGU), con el modelo Presión- Estado-Respuesta (PER) y el apoyo de Tecnologías de Información Geográfica (TIG) -imagen satelital y SIG- para desarrollar modelos urbanos y atributos e Indicadores de Sostenibilidad Urbana (ISU) específicos. La sostenibilidad y gobernanza (participación-interacción política y social multinivel), se asumieron como principios clave del estudio, para la toma de decisión ética y construir una visiónhipótesis territorial integral y concertada de futuro para el conjunto urbanos ZP-AMM. La ponencia concluye presentando el resultado de la aplicación de la estrategia metodológica, EPE+i = [PGU+PER+TIG] (tecnovación creativa), donde los modelos SIG de vulnerabilidad, consolidación y conformidad de uso y el modelo síntesis, conformidad-adecuación ambiental y legal de la ocupación urbana de la ZP, constituyen los atributos e ISU de Estado; los escenarios se transforman en atributos e ISU de Presión y la gobernanza, evaluada a través de tres variables, legitimidad por desempeño, gobernabilidad y participación, conforman los atributos de Respuesta y seleccionado como política urbana y visión-hipótesis territorial integral para el conjunto ZP-AMM, el escenario E2: Corredores de Expansión Tendencial, porque organiza la ocupación lineal urbana actual, a lo largo de los corredores metropolitanos, manteniendo las áreas intermedias como zonas verdes de protección.Urban sprawl in Latin-American and Venezuelan cities derives from uncontrolled urban expansion of the periphery, due to the absence or infringement of geographical and legal restrictions through planned and spontaneous urban occupation (hybrid urbanization). This in turn results from migration and territorial laissez faire; limited urban management capacity and sustainability culture in public, private and community institutions although they perceived and inhabit a precarious environment and frequently protest demanding services, security and houses. For Sempere (2005, is caused by illegal ways of habitat production based on low density and extensive typologies. This urban pattern generates strong pressures against which there is no institutional capacity or will to respond due to political or ideological reasons. This disperse-unsustainable model in Maracaibo (capital of the Zulia State, located at the western extreme of Venezuela) has led to the explosion of the city boundaries, and the occupation of the edges of the metropolitan urban corridors, which run from the city across the Protective Zone (PZ). The PZ is a green belt of 20.800 Hectares, decreed in 1989 to act as a policy-container of urban growth by defining the city west boundaries and is in the process of transformation-mutation by urban rituals in expansion. It is the territorial expression of the contemporary forms of making city which result from the practice of the visible management government (VMG) in metropolitan Maracaibo, referred by Ferrer and others (2005) as Maracaibo’s metropolitan archipelago (MAM). The paper describes the method, innovative planningevaluation strategy (IPES) and the results of a study that evaluates the impact of sprawl -urban occupation of the Protective Zone (PZ)-, in Maracaibo’s -hybrid metropolitan archipelago- (HMA) sustainability. The IPES fills the gap of the local urban planning assuming the principles of sustainable development (SD) by means of braiding the urban planning process (UPP) with the Pressure-State-Response Model (PSR) and Geographical Information Technologies (GIT) -satellite images and GIS- to develop urban models, specific attributes and urban sustainable indicators (USI). The IPES (UPP+PSR) is a multilayered-relational model that works, within the PSR model and grapping this model with the UPP. In this model, the causes of environmental changes, Pressure are correlated with the urban-spatial scenarios, their effects State, with the diagnose synthesis and, the Response with the multilevel government and stakeholders, urban projects, actions and policies, proposed and undertaken to deal with these changes. To reach an ethical decision, a concerted vision of the future scenarios and to build an integral territorial hypothesis for the PZHMA, sustainability and governance -stakeholders’ participation- were the key principles of the study. The paper concludes presenting the IPES model (creative technovation), where the GIS models of vulnerability, consolidation, conformity of usage and the model synthesis, environmental and legal conformity-adequation of the urban occupation, serve as specific State Attributes; the envisioned urban - spatial scenarios constituted the Attributes of Pressure and urban governance, measured through three variables, legitimacy by performance, governability and participation, configured the Response Attributes and selecting as policy and integral hypothesis –vision for the PZ-MAM the E2 Scenario: Corridors of Tendencial Expansion because controls, adjusts and organises the present lineal urban occupation along the metropolitan corridors maintaining intermediate areas of green protection and re-creates a new hybrid sustainable urban landscape, a compact, dense and multifunctional-polycentric PZ-MAM.Peer Reviewe

INTEGRANTES EQUIPO DE EDUCACIÓN VIAL EN MADRID [Material gráfico]

Copia digital. Madrid : Ministerio de Educación, Cultura y Deporte. Subdirección General de Coordinación Bibliotecaria, 201

The hydrogen and helium lines of the symbiotic binary Z And during its brightening at the end of 2002

High resolution observations in the region of the lines Halpha, He II 4686 and Hgamma of the spectrum of the symbiotic binary Z And were performed during its small-amplitude brightening at the end of 2002. The profiles of the hydrogen lines were double-peaked. These profiles give a reason to suppose that the lines can be emitted mainly by an optically thin accretion disc. The Halpha line is strongly contaminated by the emission of the envelope, therefore for consideration of accretion disc properties we use the Hgamma line. The Halpha line had broad wings which are supposed to be determined mostly from radiation damping but high velocity stellar wind from the compact object in the system can also contribute to their appearance. The Hgamma line had a broad emission component which is assumed to be emitted mainly from the inner part of the accretion disc. The line He II 4686 had a broad emission component too, but it is supposed to appear in a region of a high velocity stellar wind. The outer radius of the accretion disc can be calculated from the shift between the peaks. Assuming, that the orbit inclination can ranges from 47$^\circ$ to 76$^\circ$, we estimate the outer radius as 20 - 50 R_sun. The behaviour of the observed lines can be considered in the framework of the model proposed for interpretation of the line spectrum during the major 2000 - 2002 brightening of this binary.Comment: 19 pages, 5 figures. Accepted for publication in Astronomy Report

Geometric Mixing, Peristalsis, and the Geometric Phase of the Stomach

Mixing fluid in a container at low Reynolds number - in an inertialess environment - is not a trivial task. Reciprocating motions merely lead to cycles of mixing and unmixing, so continuous rotation, as used in many technological applications, would appear to be necessary. However, there is another solution: movement of the walls in a cyclical fashion to introduce a geometric phase. We show using journal-bearing flow as a model that such geometric mixing is a general tool for using deformable boundaries that return to the same position to mix fluid at low Reynolds number. We then simulate a biological example: we show that mixing in the stomach functions because of the "belly phase": peristaltic movement of the walls in a cyclical fashion introduces a geometric phase that avoids unmixing.Comment: Revised, published versio

Chemical characterization and enological potential of less frequent red grape Uruguayan varieties by study secondary metabolites

Study of secondary grape metabolites, such as polyphenol compounds (anthocyanins, flavonols, flavan-3-ols), volatile compounds present in grapes in both free and glycoside forms (monoterpenols, norisoprenoids, benzenoids), allowed us to characterize grape varieties and to suggest the best winemaking practices to maximize their enological potential. The Vitis viníferas studied in the present work are less frequent red grape varieties cultivated in small vineyards in southern Uruguay (Montevideo and Canelones Provinces): Ancellota, Aspiran Bouschet (syn. Lacryma Christi), Marselan (Grenache × Cabernet Sauvignon), Arinarnoa (Tannat × Cabernet Sauvignon), Egiodola (Abouriou × Tinta Negra Mole) and Caladoc (Malbec × Grenache)

Theoretical description of phase coexistence in model C60

We have investigated the phase diagram of the Girifalco model of C60 fullerene in the framework provided by the MHNC and the SCOZA liquid state theories, and by a Perturbation Theory (PT), for the free energy of the solid phase. We present an extended assessment of such theories as set against a recent Monte Carlo study of the same model [D. Costa et al, J. Chem. Phys. 118:304 (2003)]. We have compared the theoretical predictions with the corresponding simulation results for several thermodynamic properties. Then we have determined the phase diagram of the model, by using either the SCOZA, or the MHNC, or the PT predictions for one of the coexisting phases, and the simulation data for the other phase, in order to separately ascertain the accuracy of each theory. It turns out that the overall appearance of the phase portrait is reproduced fairly well by all theories, with remarkable accuracy as for the melting line and the solid-vapor equilibrium. The MHNC and SCOZA results for the liquid-vapor coexistence, as well as for the corresponding critical points, are quite accurate. All results are discussed in terms of the basic assumptions underlying each theory. We have selected the MHNC for the fluid and the first-order PT for the solid phase, as the most accurate tools to investigate the phase behavior of the model in terms of purely theoretical approaches. The overall results appear as a robust benchmark for further theoretical investigations on higher order C(n>60) fullerenes, as well as on other fullerene-related materials, whose description can be based on a modelization similar to that adopted in this work.Comment: RevTeX4, 15 pages, 7 figures; submitted to Phys. Rev.

Time resolved spectroscopy of BD+46 442: gas streams and jet creation in a newly discovered evolved binary with a disk

Previous studies have shown that many post-AGB stars with dusty disks are associated with single-lined binary stars. To verify the binarity hypothesis on a larger sample, we started a high-resolution spectral monitoring of about 40 field giants, whose binarity was suspected based on either a light curve, an infrared excess, or a peculiar chemical composition. Here we report on the discovery of the periodic RV variations in BD+46 442, a high-latitude F giant with a disk. We interpret the variations due to the motion around a faint companion, and deduce the following orbital parameters: Porb = 140.77 d, e = 0.083, asini=0.31 AU. We find it to be a moderately metal-poor star ([M/H]=-0.7) without a strong depletion pattern in the photospheric abundances. Interestingly, many lines show periodic changes with the orbital phase: Halpha switches between a double-peak emission and a PCyg-like profiles, while strong metal lines appear split during the maximum redshift. Similar effects are likely visible in the spectra of other post-AGB binaries, but their regularity is not always realized due to sporadic observations. We propose that these features result from an ongoing mass transfer from the evolved giant to the companion. In particular, the blue-shifted absorption in Halpha, which occurs only at superior conjunction, may result from a jet originating in the accretion disk around the companion and seen in absorption towards the luminous primary.Comment: 16 pages, accepted in A&

XNAP: Making LSTM-based Next Activity Predictions Explainable by Using LRP

Predictive business process monitoring (PBPM) is a class of techniques designed to predict behaviour, such as next activities, in running traces. PBPM techniques aim to improve process performance by providing predictions to process analysts, supporting them in their decision making. However, the PBPM techniques` limited predictive quality was considered as the essential obstacle for establishing such techniques in practice. With the use of deep neural networks (DNNs), the techniques` predictive quality could be improved for tasks like the next activity prediction. While DNNs achieve a promising predictive quality, they still lack comprehensibility due to their hierarchical approach of learning representations. Nevertheless, process analysts need to comprehend the cause of a prediction to identify intervention mechanisms that might affect the decision making to secure process performance. In this paper, we propose XNAP, the first explainable, DNN-based PBPM technique for the next activity prediction. XNAP integrates a layer-wise relevance propagation method from the field of explainable artificial intelligence to make predictions of a long short-term memory DNN explainable by providing relevance values for activities. We show the benefit of our approach through two real-life event logs