994 resultados para Settling


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Dewatering of microalgal culture is a major bottleneck towards the industrial-scale processing of microalgae for bio-diesel production. The dilute nature of harvested microalgal cultures poses a huge operation cost to dewater; thereby rendering microalgae-based fuels less economically attractive. This study explores the influence of microalgal growth phases and intercellular interactions during cultivation on dewatering efficiency of microalgae cultures. Experimental results show that microalgal cultures harvested during a low growth rate phase (LGRP) of 0.03 d-1 allowed a higher rate of settling than those harvested during a high growth rate phase (HGRP) of 0.11 d-1, even though the latter displayed a higher average differential biomass concentration of 0.2 g L-1 d-1. Zeta potential profile during the cultivation process showed a maximum electronegative value of -43.2 ± 0.7 mV during the HGRP which declined to stabilization at -34.5 ± 0.4 mV in the LGRP. The lower settling rate observed for HGRP microalgae is hence attributed to the high stability of the microalgal cells which electrostatically repel each other during this growth phase. Tangential flow filtration of 20 L HGRP culture concentrated 23 times by consuming 0.51 kWh/m3 of supernatant removed whilst 0.38 kWh/m3 was consumed to concentrate 20 L of LGRP by 48 times.

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When settling, people often use cultural schema from their original homeland to build familiarity in unfamiliar surrounds. This paper draws on ethnographic fieldwork conducted by the first author in Brisbane, with the Karen community from Burma, during which participant observation and interview methods were used. We present an ethnographic account of the Brisbane Karen wrist-tying ceremony. The ceremony acts as an insight into the challenges for Karen whilst settling into Australia. It reflects multiple accounts of history and tradition, but simultaneously speaks to emerging, contemporary Karen contexts. This research contributes to richer understandings of settlement: it frames transnational cultural practice as a flexible mode of integration, rather than an exclusionary mode of othering. We propose that the integrative discourse of the ceremony creates familiarity and social connection in local and diasporic spaces. This acts as a counter to the challenges of Karen settlement including the negotiations of local/global identity politics.

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This doctoral dissertation examines the description of the North as it appears in the Old English Orosius (OE Or.) in the form of the travel accounts by Ohthere and Wulfstan and a catalogue of peoples of Germania. The description is discussed in the context of ancient and early medieval textual and cartographic descriptions of the North, with a special emphasis on Anglo-Saxon sources and the intellectual context of the reign of King Alfred (871-899). This is the first time that these sources, a multidisciplinary approach and secondary literature, also from Scandinavia and Finland, have been brought together. The discussion is source-based, and archaeological theories and geographical ideas are used to support the primary evidence. This study belongs to the disciplines of early medieval literature and (cultural) history, Anglo-Saxon studies, English philology, and historical geography. The OE Or. was probably part of Alfred s educational campaign, which conveyed royal ideology to the contemporary elite. The accounts and catalogue are original interpolations which represent a unique historical source for the Viking Age. They contain unparalleled information about peoples and places in Fennoscandia and the southern Baltic and sailing voyages to the White Sea, the Danish lands, and the Lower Vistula. The historical-philological analysis reveals an emphasis on wealth and property, rank, luxury goods, settlement patterns, and territorial divisions. Trade is strongly implied by the mentions of central places and northern products, such as walrus ivory. The references to such peoples as the Finnas, the Cwenas, and the Beormas appear in connection with information about geography and subsistence in the far North. Many of the topics in the accounts relate to Anglo-Saxon aristocratic culture and interests. The accounts focus on the areas associated with the Northmen, the Danes and the Este. These areas resonated in the Anglo-Saxon geographical imagination: they were curious about the northern margin of the world, their own continental ancestry and the geography of their homeland of Angeln, and they had an interest in the Goths and their connection with the southern Baltic in mythogeography. The non-judgemental representation of the North as generally peaceful and relatively normal place is related to Alfredian and Orosian ideas about the unity and spreading of Christendom, and to desires for unity among the Germani and for peace with the Vikings, who were settling in England. These intellectual contexts reflect the innovative and organizational forces of Alfred s reign. The description of the North in the OE Or. can be located in the context of the Anglo-Saxon worldview and geographical mindset. It mirrors the geographical curiosity expressed in other Anglo-Saxon sources, such as the poem Widsith and the Anglo-Saxon mappa mundi. The northern section of this early eleventh-century world map is analyzed in detail here for the first time. It is suggested that the section depicts the North Atlantic and the Scandinavian Peninsula. The survey of ancient and early medieval sources provides a comparative context for the OE Or. In this material, produced by such authors as Strabo, Pliny, Tacitus, Jordanes, and Rimbert, the significance of the North was related to the search for and definition of the northern edge of the world, universal accounts of the world, the northern homeland in the origin stories of the gentes, and Carolingian expansion and missionary activity. These frameworks were transmitted to Anglo-Saxon literary culture, where the North occurs in the context of the definition of Britain s place in the world.

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Pond apple invades riparian and coastal environments with water acting as the main vector for dispersal. As seeds float and can reach the ocean, a seed tracking model driven by near surface ocean currents was used to develop maps of potential seed dispersal. Seeds were ‘released’ in the model from sites near the mouths of major North Queensland rivers. Most seeds reach land within three months of release, settling predominately on windward-facing locations. During calm and monsoonal conditions, seeds were generally swept in a southerly direction, however movement turns northward during south easterly trade winds. Seeds released in February from the Johnstone River were capable of being moved anywhere from 100 km north to 150 km south depending on prevailing conditions. Although wind driven currents are the primary mechanism influencing seed dispersal, tidal currents, the East Australian Current, and other factors such as coastline orientation, release location and time also play an important role in determining dispersal patterns. In extreme events such as tropical cyclone Justin in 1997, north east coast rivers could potentially transport seed over 1300 km to the Torres Strait, Papua New Guinea and beyond.

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The project was successful across all objectives, making demonstrable progress in support of establishing tropical lobster farming in Indonesia. The industry remains most active in Lombok where lobster seed resources are most abundant, and impact has been greatest there. Nevertheless, project activities have established activity and interest in lobster farming in other provinces and particularly Aceh and, South and Southeast Sulawesi. The project met all of its 23 milestones with the exception of publishing a production manual, which has been held over until 2017. For several milestone activities, further research will be required to build on the outcomes generated and reach practical commercial outputs. The research was instigated to address the opportunity to establish a significant small-holder based industry in Indonesia that could alleviate poverty in coastal communities. The premise was that such an industry – lobster farming, had been established in Vietnam, with ACIAR involvement, and it could be replicated in Indonesia where the availability of necessary basic requirements had been confirmed through a previous ACIAR project focussed in Vietnam (FIS/2001/058). The broad aim was to assess, develop and expand the resources of naturally settling lobster seed (puerulus), and develop grow out of those seed to meet export market demand. This was to be achieved by adapting and transferring to Indonesia technology from Vietnam, where lobster farming had become a successful industry producing 1,500 tonnes of export quality lobsters valued at $A100 million.

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Transcript of an oral history interview with Susanne Harris Flodstrom, née Neuwalder, conducted by Deborah Dwork in New Haven, CT in nine sessions 1993-1994.

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The papers consist of correspondence and reports of Cecelia Razovsky (married name: Davidson), noted social worker specializing in immigration and resettlement of refugees. The collection includes information about her work with the National Council of Jewish Women in the 1920's, and with the National Refugee Service (and predecessor organizations) in the 1930's. Information is included about her work as a Resettlement Supervisor in the post-World War II DP camps in Europe, and as a field worker in the southwestern U.S. for the United Service for New Americans in 1950. The collection contains reports and correspondence from her trips to South America, primarily Brazil: to explore possibilities of refugee settlement in 1937 and 1946; as a representative for United HIAS Service to aid in settling Egyptian and Hungarian refugees in 1957-58; and as a pleasure trip and evaluation of the changes in the Jewish community of the country in 1963. Also included in the collection are many of Razovsky's articles, plays, and pamphlets.

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Can war be justified? Expressions of opinions by the general assemblies of the World Council of Churches on the question of war as a method of settling conflicts. The purpose of this study is to describe and analyse the expressions of opinions recorded in the documents of the general assemblies of the WCC during the Cold War period from 1948 to 1983 on the use of war as a method of settling international and national conflicts. The main sources are the official reports of the WCC´s assemblies during the years 1948 to 1983. This study divides the discussions into three periods. The first period (1949-1968) is dominated by the pressures arising from the Second World War. Experiences of the war led the assemblies of the WCC to the conclusion that modern warfare as a method of settling conflicts should be rejected. Modern war was contrary to God´s purposes and the whole meaning of creation, said the assembly. Although the WCC rejected modern war, it left open the possibility of conflict where principles of just war may be practised. The question of war was also linked to the state and its function, which led to the need to create a politically neutral doctrine for the socio-ethical thinking of churches and of the WCC itself. The doctrine was formulated using the words "responsible society". The question of war and socio-ethical thinking were on the WCC`s agenda throughout the first period. Another issue that had an influence on the first period was the increasing role of Third World countries. This new dimension also brought new aspects to the question of war and violence. The second period (1968-1975) presented greater challenges to the WCC, especially in traditional western countries. The Third World, political activity in the socialist world and ideas of revolution were discussed. The WCC`s fourth Assembly in Uppsala was challenged by these new ideas of revolution. The old doctrine of "responsible society" was seen by many participants as unsuitable in the modern world, especially for Third World countries. The situation of a world governed by armaments, causing social and economic disruption, was felt by churches to be problematic. The peace movement gathered pace and attention. There was pressure to see armed forces as an option on the way to a new world order. The idea of a just war was challenged by that of just revolution. These ideas of revolution did not receive support from the Uppsala Assembly, but they pressured the WCC to reconsider its socio-ethical thinking. Revolution was seen as a possibility, but only when it could be peaceful. In the Nairobi Assembly the theme of just, participatory and sustainable society provided yet another viewpoint, dealing with the life of the world and its problems as a whole. The third period (1975-1983) introduced a new, alternative doctrine the "JPIC Process", justice, peace and the integrity of creation for social thinking in the WCC. The WCC no longer wanted to discuss war or poverty as separate questions, but wanted to combine all aspects of life to see the impact of an arms-governed world on humankind. Thus, during the last period, discussions focused on socio-ethical questions, where war and violence were only parts of a larger problem. Through the new JPIC Process, the WCC`s Assembly in Vancouver looked for a new world, one without violence, in all aspects of life. Despite differing opinions in socio-ethical thinking, the churches in the WCC agreed that modern warfare cannot be regarded as acceptable or just. The old idea of a "just war" still had a place, but it was not seen by all as a valid principle. As a result the WCC viewed war as a final solution to be employed when all other methods had failed. Such a war would have to secure peace and justice for all. In the discussions there was a strong political east-west divide, and, during the last two decades, a north-south divide as well. The effect of the Cold War was obvious. In the background to the theological positions were two main concepts namely the idea of God´s activity in man´s history through the so-called regiments and, the concept of the Kingdom of God on Earth.

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Various clippings and articles about the work of Erwin Gruen and his Jewish-German background (1965-1993); Letter by Gruen describing his experiences during the Nazi period.

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Of the many factors that govern the settling phenomenon, the flow velocity in the settling tanks can be controlled favorably by fixing suitably designed weirs at the outlets of the tanks. The velocity at the bottom should not dislodge the particles that have already settled. These requirements might be met with by velocities which are controlled to be constant with respect to the depth of flow, or velocities which reduce linearly with increasing depth or velocities that vary inversely with the depth. To achieve these types of velocity control, new proportional weirs have been designed. Very near to the outlet of the tank, over a small length, the flow was found to be turbulent and noncompliant with the expected type of velocity control. This small length of the disturbance may be provided over and above the theoretical settling length of the tank, for efficient sedimentation.

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Population dynamics are generally viewed as the result of intrinsic (purely density dependent) and extrinsic (environmental) processes. Both components, and potential interactions between those two, have to be modelled in order to understand and predict dynamics of natural populations; a topic that is of great importance in population management and conservation. This thesis focuses on modelling environmental effects in population dynamics and how effects of potentially relevant environmental variables can be statistically identified and quantified from time series data. Chapter I presents some useful models of multiplicative environmental effects for unstructured density dependent populations. The presented models can be written as standard multiple regression models that are easy to fit to data. Chapters II IV constitute empirical studies that statistically model environmental effects on population dynamics of several migratory bird species with different life history characteristics and migration strategies. In Chapter II, spruce cone crops are found to have a strong positive effect on the population growth of the great spotted woodpecker (Dendrocopos major), while cone crops of pine another important food resource for the species do not effectively explain population growth. The study compares rate- and ratio-dependent effects of cone availability, using state-space models that distinguish between process and observation error in the time series data. Chapter III shows how drought, in combination with settling behaviour during migration, produces asymmetric spatially synchronous patterns of population dynamics in North American ducks (genus Anas). Chapter IV investigates the dynamics of a Finnish population of skylark (Alauda arvensis), and point out effects of rainfall and habitat quality on population growth. Because the skylark time series and some of the environmental variables included show strong positive autocorrelation, the statistical significances are calculated using a Monte Carlo method, where random autocorrelated time series are generated. Chapter V is a simulation-based study, showing that ignoring observation error in analyses of population time series data can bias the estimated effects and measures of uncertainty, if the environmental variables are autocorrelated. It is concluded that the use of state-space models is an effective way to reach more accurate results. In summary, there are several biological assumptions and methodological issues that can affect the inferential outcome when estimating environmental effects from time series data, and that therefore need special attention. The functional form of the environmental effects and potential interactions between environment and population density are important to deal with. Other issues that should be considered are assumptions about density dependent regulation, modelling potential observation error, and when needed, accounting for spatial and/or temporal autocorrelation.

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Settling, dewatering and filtration of flocs are important steps in industry to remove solids and improve subsequent processing. The influence of non-sucrose impurities (Ca2+, Mg2+, phosphate and aconitic acid) on calcium phosphate floc structure (scattering exponent, Sf), size and shape were examined in synthetic and authentic sugar juices using X-ray diffraction techniques. In synthetic juices, Sf decreases with increasing phosphate concentration to values where loosely bound and branched flocs are formed for effective trapping and removal of impurities. Although, Sf did not change with increasing aconitic acid concentration, the floc size significantly decreased reducing the ability of the flocs to remove impurities. In authentic juices, the flocs structures were marginally affected by increasing proportions of non-sucrose impurities. However, optical microscopy indicated the formation of well-formed macro-floc network structures in sugar cane juices containing lower proportions of non-sucrose impurities. These structures are better placed to remove suspended colloidal solids.

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This paper begins with the assertion that research grounded in creative practice constitutes a new paradigm. We argue both for and against the idea. We argue against the idea in terms of applying it to the idealised ‘lone artist’ engaged in the production of their art, whose focus of research is a self-reflection upon the art they produce, and whose art is also the findings of the research. Our position is that such an approach cannot be considered as anything other than a form of auto-phenomenography, that such efforts are part of qualitative research, and they are thus trivial in paradigmatic terms. However, we argue in the positive for understanding the artistic event – by which we mean any mass ecology of artistic practice – as being paradigmatically new in terms of research potentials and demands. Our exemplar for that argument is a practice-led, large-scale annual event called Indie 100 which has run for five years and has demonstrated a distinct paradigmatic ‘settling in’ over its duration while clearly pushing paradigmatic boundaries for research into creative practice.

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An aeration process in ail activated sludge plant is a continuous-flow system. In this system, there is a steady input flow (flow from the primary clarifier or settling tank with some part from the secondary clarifier or secondary settling tank) and output flow connection to the secondary clarifier or settling tank. The experimental and numerical results obtained through batch systems can not be relied on and applied for the designing of a continuous aeration tank. In order to scale up laboratory results for field application, it is imperative to know the geometric parameters of a continuous system. Geometric parameters have a greater influence on the mass transfer process of surface aeration systems. The present work establishes the optimal geometric configuration of a continuous-flow surface aeration system. It is found that the maintenance of these optimal geometric parameters systems result in maximum aeration efficiency. By maintaining the obtained optimal geometric parameters, further experiments are conducted in continuous-flow surface aerators with three different sizes in order to develop design curves correlating the oxygen transfer coefficient and power number with the rotor speed. The design methodology to implement the presently developed optimal geometric parameters and correlation equations for field application is discussed.

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The adsorption behaviour of an oxidised starch AP as well as that of calcium onto haematite have been studied both individually and together. While the adsorption density of starch AP onto haematite is enhanced in the presence of calcium, the adsorption of calcium onto haematite is not promoted by starch AP. Flocculation tests on haematite ore fines in the presence of starch AP and calcium chloride reveal that the sequence in which calcium and starch are added governs the settling rates and turbidity values. Zeta potential, viscosity and conductivity measurements, and calcium ion binding studies with starch AP indicate calcium-starch interactions. Possible mechanisms involved in such interactions with respect to haematite flocculation have been discussed.