Search results for "vertical"
showing 10 items of 417 documents
Molecular and isotopic composition of free hydrocarbon gases from Sicily, Italy
2004
[1] Chemical and isotopic data have been used as geochemical tracers for a genetic characterization of hydrocarbon gases from a total of eleven manifestations located in Eastern and Central-Southern Sicily (Italy). The molecular analysis shows that almost all the samples are enriched in methane (up to 93.2% Vol.), with the exception of four gas samples collected around Mt. Etna showing high mantle-derived CO2 content. Methane isotope signatures suggest that these are thermogenic gases or a mixture between thermogenic gases and microbial gases. Although samples from some mud volcanoes in Southern Sicily (Macalube di Aragona) show isotope signatures consistent with a mixing model between ther…
Solvent Determines Nature of Effective Interactions between Nanoparticles in Polymer Brushes
2015
We study the effective interaction between two parallel rod-like nanoparticles in swollen and collapsed polymer brushes as a function of penetration depth by 2D self-consistent field calculations. In vertical direction, the interaction is always attractive. In lateral direction, the behavior under good and poor solvent conditions is qualitatively different. In swollen brushes (good solvent), nanoparticles always repel each other. In collapsed brushes (poor solvent), we identify two different regimes: an immersed regime, where the nanoparticles are fully surrounded by the brush, and an interfacial regime, where they are located in the interface between brush and solvent. In the immersed regi…
Calculation of low bandgap homopolymers: Comparison of TD-DFT methods with experimental oligomer series
2016
Made available in DSpace on 2018-12-11T17:26:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-02-01 The performance of different DFT functionals (B3LYP, BHLYP, CAM-B3LYP, M06HF) on the prediction of vertical transition energies Evert of low bandgap homopolymers is tested against the experimentally available oligomer series (thienopyrazines and thienothiophenes). This allows for a detailed and accurate comparison on the consistency of DFT methods for chainlength evolution and polymer limit prediction, and for an understanding of geometry and time-dependent contributions to Evert by combinatorial analysis. Together with former studies on wide/medium bandgap polymers and low bandgap c…
The Hold-Up Problem in Agricultural Contracts. A Study of Contractual Correlations Between Polish Groups of Agricultural Producers and First Recipien…
2018
Problem pułapki przed- i post-kontraktowej ma miejsce, gdy partnerzy cechują się oportunizmem, kontrakt jest niekompletny i występuje konieczność dokonania inwestycji zarówno o charakterze specyficznym, jak i ogólnego użytku. Na problem pułapki kontraktowej mogą być narażeni producenci rolni choćby ze względu na słabszą pozycję rynkową czy też niski poziom zintegrowania horyzontalnego. W artykule wyznaczono dwa cele. Pierwszy stanowi identyfikację umów rolnych, z których realizacją wiązało się dokonanie inwestycji w aktywa trwałe (problem pułapki post-kontraktowej). Drugim zaś jest rozpoznanie grup producentów rolnych, które według własnej opinii były w toku swej działalności narażone na wy…
Digital zenith camera for vertical deflection determination
2012
Recent accomplishments in advancement of accurate astrometric reference star catalogues, development of digital imaging technology, high accuracy tiltmeter technology, and geocentric coordinate availability provided by GNSS, have made possible accurate, fast and automated determination of vertical deflections using astrometric methods. Zenith cameras for this kind of measurements have been developed or are being developed by several research groups. The paper describes a research project by Institute of Geodesy and Geoinformation, intended to design a portable digital zenith camera for vertical deflection determination with 0.1” expected accuracy. Camera components are described, proposed d…
Size distribution of Daphnia longispina in the vertical profile
1997
D. longispina of the meromictic lake El Tobar is a round-headed form. It never has a helmet, but in summer a small proportion of immature individuals (0.9–1.2 mm females and males) have one or two neck teeth. The size structure of this Daphnia population, as well as the vertical distribution and migration of different size-classes, were studied in September and November of 1991 and April of 1992. The large variation in mean size and size at first reproduction, as well as the occurrence of different patterns of vertical migration are interpreted as responses to different predator situations. At the end of April, when Daphnia mortality by visually hunting predators is dominating, a typical no…
Diel vertical migration by Daphnia longispina in a Spanish lake: Genetic sources of distributional variation
1995
Individuals of many zooplankton species undergo diel vertical migration in which they move toward the surface after sunset and return to deeper waters at dawn. However, even when vertical migration can be clearly demonstrated by mapping the distributions of individuals at noon and midnight, at any given time the population is usually scattered over ‘a broad range of depths. This paper focuses on a major potential source of the variance associated with depth distributions. We have used electrophoretic analysis of isozymes to identify “clones” of Daphnia longispina in a Spanish lake. In September 199 1, two clones constituted 5 5% of the individuals collected at noon and midnight on each oftw…
Diel feeding periodicity, daily ration and prey selectivity in juvenile brown trout in a subarctic river
1999
Feeding of age-1 brown trout Salmo trutta in a third-order river in northern Finland was usually highest in the twilight hours and lowest around midday. Diel periodicity in food intake was less distinct and rarely significant for age-0 trout. Daily rations declined seasonally, being lowest in October, and highest in June (age-1 trout) or early August (age-0 trout). Prey selection did not differ between day and night, but differences between age classes and sampling dates were distinct. Age-0 trout preferred Ephemerella nymphs in summer and Micrasema larvae later in the season. Age-1 trout fed selectively on caddis larvae on all sample dates. Aerial insects and Baetis nymphs were avoided by …
Construyendo el espacio geográfico a partir del mundo subjetivo de los alumnos
2014
El presente trabajo se enmarca dentro de la geografía subjetiva. A través de un estudio de caso se observa cómo las experiencias personales de los niños y niñas influyen en la construcción y en la deformación del espacio geográfico. Este documento puede servir de orientación para poner en práctica un proyecto de innovación, pues se ofrece una secuencia de actividades donde se trabaja el conocimiento y la autonomía espacial. This work is part of subjective geography. A case study shows how children's personal experiences influence the construction and deformation of geographic space. This may provide guidance to implement an innovation project. The series of activities which are proposed wor…
SVILUPPO E INTEGRAZIONE DI FILIERA. IL FUTURO DELL’IMPRESA ITTICA SICILIANA
2015
Le attività dell’impresa che opera nel settore ittico non dipendono solo dalla sue capacità e dalle sue strategie, ma sono influenzate, direttamente o indirettamente, anche dalle azioni dei diversi attori che operano all’interno della filiera in cui essa opera. Il presente contributo prende in esame brevemente il ruolo di tali attori in Sicilia per poi proporre due casi studio, quello del Progetto Manifattura di Rovereto e quello del Fisch Markt di Amburgo come esempi a cui ispirarsi nell’incentivazione dei processi di integrazione della filiera ittica siciliana e nella prospettiva del superamento di una logica di mera “sopravvivenza” delle sue imprese. The activities of the company that op…