2,011 research outputs found
Detergency in Liquid CO2
No full textIn this dissertation we study Detergency in liquid Carbon Dioxide. Detergency is the cleaning performance of additives, surfactants in particular, in washing fluids. Liquid CO2 is under consideration, for environmental and toxicological reasons, to replace perchloro-ethylene as the solvent in textile dry cleaning technology. Inherent problems of such a transition were confronted with the methodology of chemical engineering design. The Basic Cycle of Design (BCD) approach was used as a pathway for designing a detergent. The BCD also establishes the structural framework of the thesis, which can, therefore, be read as records from a successful product engineering project, in which an effective detergent has been designed for a new dry cleaning solvent. The Dynamic Detergency Model (DDM), which succeeds to explain the role of surfactants in the washing operation, is used as a rational starting point for the design of a detergent in liquid CO2. According to this model, such a surfactant must be: sparingly soluble in the solvent, surface-active and able to form micelles in the solution. The different experiments carried out (solubility, interfacial-tension and dye solubilisation measurements), show that a number of molecules of the homologous polyoxyethylene/alkane series, generally described by the shorthand formula CiEj did indeed behave as surfactants and can be then considered detergents for liquid CO2. In the technical evaluation of the detergents, at laboratory as well as at semi-pilot scale, high washing performances were obtained. They are, indeed, as good for dry cleaning textiles as the present perchloro-ethylene (Perc) technology.Applied Science
The influence of the North Atlantic Oscillation on the sea level around the northern European coasts reconsidered: the thermosteric effects
No full textThe thermosteric contribution of the North Atlantic Oscillation (NAO) to the North Sea sea-level for the winter period is investigated. Satellite sea surface temperature as well as in situ measurements are used to define the sensitivity of winter water temperature to the NAO as well as to determine the trends in temperature. The sea surface temperature sensitivity to the NAO is about 0.85°C per unit NAO, which results in thermosteric sea-level changes of about 1–2cm per unit NAO. The sensitivity of sea surface temperatures to the NAO is strongly time-dependent. Model data from a two-dimensional hydrodynamic tide+surge model are used in combination with the estimated thermosteric anomalies to explain the observed sea-level changes and, in particular, the sensitivity of the datasets to the NAO variability. The agreement between the model and the observed data is improved by the inclusion of the thermosteric effect
'Her Irish Heritage' : Annie M.P Smithson and autobiography
No full textThis paper examines some aspects of the work of Annie M.P. Smithson, the author of 21 romance novels between 1917 and 1946. Her attitudes towards women, religion and politics are explored, and the importance of autobiography in her fiction discussed.Cet article analyse divers aspects de l'oeuvre d'Annie M.P. Smithson, l'auteur de vingt et un romans 'romanesques' publiés entre 1917 et 1946. Il étudie son attitude concernant les femmes, la religion, la politique, ainsi que le rôle de l'autobiographie dans sa fiction.Walsh Oonagh. 'Her Irish Heritage' : Annie M.P Smithson and autobiography. In: Études irlandaises, n°23-1, 1998. pp. 27-42
A century of sea level data and the UK's 2013/14 storm surges: an assessment of extremes and clustering using the Newlyn tide gauge record
No full textFor the UK's longest and most complete sea level record (Newlyn), we assess extreme high waters and their temporal clustering; prompted by the 2013/2014 winter of storms and flooding. These are set into context against this almost 100-year record. We define annual periods for which storm activity and high sea levels can be compared on a year-by-year basis. Amongst the storms and high tides which affected Newlyn, the recent winter produced the largest recorded high water level (3 February 2014) and five other high water events above a 1 in 1-year return period. The large magnitude of tide and mean sea level, and the close inter-event spacings (of large return period high waters), suggests that the 2013/2014 extreme high water level "season" can be considered the most extreme on record. However, storm and sea level events may be classified in different ways. For example, in the context of sea level rise (which we calculate linearly as 1.81 ± 0.1 mm yr?1 from records between 1915 to 2014), a lower probability combination of surge and tide occurred on 29 January 1948, whilst the 1995/1996 storm surge season saw the most high waters of ? the 1 in 1-year return period. We provide a basic categorisation of the four types of extreme high water level cluster, ranging from consecutive tidal cycles to multiple years. The assessment is extended to other UK sites (with shorter sea level records and different tide-surge characteristics), which suggests 2013/2014 was particularly unusual. Further work will assess clustering mechanisms and flood system "memory"
Il ruolo della linguistica in un'iniziativa di internazionalizzazione
No full textThe author deals with the role of linguistic sciences and language teaching in the internationalization project of an e-learning Specialization Course
The influence of steady blowing and roughness on transitional separated boundary layers
No full textThis paper presents the results of a study between two types of forcing, namely steady blowing and a tripwire, on the control of laminar separated boundary layers. The analysis focuses on the differences in the transition process between these two types of forcing. This effect will be studied using direct numerical simulation. The main differences consists in the coherent structures formed during transition and the overall kinetic energy growth
Gusmani grecista
No full textThe author deals with the Roberto Gusmani's works about Ancient Greek language
Skin-Friction Measurements on Mathematically Generated Roughness in a Turbulent Channel Flow
No full textEngineering systems are affected by surface roughness, however, predicting frictional drag has proven to be challenging. The present work takes a systematic approach by generating and manufacturing surfaces roughness where surface statistics, such as rms, skewness and power-spectral density can be controlled. The frictional drag on these surfaces is measured in a turbulent channel flow facility
El defensor del vínculo en las causas de nulidad matrimonial tras el m.p. Mitis Iudex
No full textCapítulos en librosLa autora estudia el rol del defensor del vínculo tras la reforma de los procesos canónicos de nulidad matrimonial introducida por el motu propio Mitis Iudex Dominus Iesus, del papa FranciscoThe author studies the role of the Defender of the Bond after the reform of the Canonical process for the declaration of the nullity of marriage, made by the m.p. of Pope Francis, Mitis Iudex Dominus Iesusinfo:eu-repo/semantics/publishedVersio
Mercanti, diplomatici e viaggiatori tra Venezia e l’Egitto
No full textThe author describes the different classes of persons who used to travel from Venice to Egypt: merchants, ambassadors and diplomats, travellers
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