bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibition of Barite Scale in the Presence of Hydrate Inhibitors
Authors: Tomson Mason B. , Kan Amy T. , Fu Gongmin 
Published: April 2006

SummaryLarge volumes of hydrate inhibitors [e.g., methanol, ethanol, monoethylene glycol (MEG), and triethylene glycol (TEG) as co-solvent] are added to control hydrate formation. Such practice has an adverse effect on scale formation because the mineral salts are generally less soluble in the cosolvent. Because of production from reservoirs, oilfield brines are often close to saturation as they enter a well; even a small amount of added methanol, ethanol, and so on is often sufficient to induce various minerals to precipitate, particularly the sparingly soluble minerals (e.g., barite). For example, barite solubility is reduced by as much as 20-fold with 50 wt% methanol.In this paper, barite nucleation rates were studied over a wide range of concentrations, such as Ba2+ (0.5 to 1.8 mm) SO42− (0.5 to 1.8 mm) methanol (0 to 40 wt%), MEG (0 to 40 wt%) or TEG (40 wt%). Barite nucleation rate is significantly accelerated in as little as 5 wt% methanol. The barite nucleation rate can be modeled with an equation modified from the classical nucleation theory in this study. The inhibition of barite by two phosphonate inhibitors and a polymer inhibitor in the cosolvent/brine solution is more complex. At lower cosolvent concentrations (&lt;30 wt%), the nucle-ation inhibition can be predicted with a previously derived semi-empirical model that mathematically separates the effect of added inhibitors from that of the uninhibited mineral phase. At high methanol (&gt;30 wt%) concentration, barite nucleation may be difficult to inhibit by scale inhibitors because of high supersaturation and the tendency of phosphonate to be precipitated as metal salt.
After-Closure Analysis To Identify Naturally Fractured Reservoirs
Authors: Chipperfield Simon 
Published: April 2006

Summary
After-closure analysis (ACA) in homogeneous-matrix reservoirs provides a method for extracting critical reservoir information from pre-frac injection tests. This paper extends the theory and practice of ACA to identify the presence of productive natural fractures.
Natural fractures are important to identify before conducting a stimulation treatment because their presence may require designs that differ from conventional matrix treatments. Literature shows that naturally fractured reservoirs are very susceptible to formation damage and require stimulation treatments to account for this issue. The historical problem, however, has been to confidently characterize the reservoirs pre-frac in terms of both the reservoir quality and the deliverability mechanism (fractures vs. matrix) before committing to these design specifications.
This paper presents the results of a simulator used to analyze the mini-frac after-closure period to identify the presence of natural fractures. The simulation results are distilled into a field implementation methodology for determining the extent of natural fracturing and the formation reservoir quality. This methodology is also applied to a field case study to verify the practicality of the technique. Unlike previous mini-frac-analysis methods, this approach identifies natural fractures that are material to production and allows the engineer to distinguish them from "fissures" that are open only during injection and are not a production mechanism.
Pore-Scale Characterization of Carbonates Using X-Ray Microtomography
Authors: Arns C. H. , Bauget F. , Limaye A. , Sakellariou A. , Senden T. J. , Sheppard A. P. , Sok R. M. , Pinczewski W. V. , Bakke S. , Berge L. I. , Øren P. -E. , Knackstedt M. A. 
Published: April 2006

Summary
A reservoir carbonate core plug has been imaged in 3D across a range of length scales using high resolution X-ray microtomography (μ-CT). Data from the original 40-mm diameter plug was obtained at the vug scale (42 μm resolution) and allows the size, shape and spatial distribution of the disconnected vuggy porosity, ϕvug = 3.5% to be measured. Within the imaged volume over 32,000 separate vugs are identified and a broad vug size distribution is measured. Higher resolution images, down to 1.1 μm resolution, on subsets of the plug exhibit interconnected porosity and allow one to measure characteristic, intergranular pore size. Pore scale structure and petrophysical properties (permeability, drainage capillary pressure, formation factor, and NMR response) are derived directly on the highest resolution tomographic dataset. We show that data over a range of porosity can be computed from a single plug fragment. Data for the carbonate core is compared to results derived from 3D images of clastic cores and strong differences noted. Computations of permeability are compared to conventional laboratory measurements on the same core material with good agreement. This demonstrates the feasibility of combining digitized images with numerical calculations to predict properties and derive cross-correlations for carbonate lithologies.
‘Ceux qui refusent le maître’: la conception du pouvoir chez les Minyanka du Mali
Authors: Colleyn Jean-Paul , Jonckers Danielle 
Published: April 2006

Opening ParagraphLe terme Minyanka est aujourd'hui officiellement consacré mais il n'est probablement qu'une déformation, due aux premiers auteurs européens, de Myanka, d'ailleurs rarement utilisé par les intéressés. Ceux que tout le monde appellent aujourd'hui les Minyanka se donnent eux-mêmes le nom de Bamana, dont la signification populaire est ‘ceux qui refusent le maître’. Par maître, il faut entendre aussi bien Allah, le dieu suprême des musulmans que le maître politique. Bamana désigne le fond de population non islamisée et demeurée fidèle à ses traditions religieuses. L'expression bamana djomo s'applique à la langue minyanka, par opposition au bambara, appelé blo djomo, la ‘langue des esclaves’, parce qu'elle était apprise par tous ceux qui étaient emmenés en captivité par les armées du royaume bambara de Ségou.
Manoeuvres and debates in the interpretation of land rights in Botswana
Authors: Peters Pauline E. 
Published: April 2006

AbstractThis article seeks to show how transformation in both practices and concepts are involved in the changing patterns of rights to and use of grazing land in Botswana over the past five decades. ‘The symbolic struggle over … legitimate naming’ (in Bourdieu's words) is centrally involved in attempts both to change and to preserve patterns of rights in land. Analysis has to address the uses of multi-referential concepts by differently placed persons. Three situations where manoeuvres over meaning are central are examined here: the shift from a more to a less incorporative organisation of resource use, the emergence of private ownership of wells and its implications for land rights, and the practical and metaphorical use of fences in a situation of conflicting rights on a divided range.RésuméCet article s'efforce de montrer comment les transformations, à la fois dans la pratique et dans les conceptions, ont contribué à modifier le système des droits et de l'usage des terres de pâturage en Botswana depuis les cinq dernières décennies. ‘La lutte symbolique pour un titre légitime’ (selon les mots de Bourdieu) tente essentiellement à la fois de changer et de préserver les systemes de droits fonciers. L'analyse doit aborder les utilisations des concepts à références multiples à travers des personnes de différents niveaux. Trois situations ou les manoeuvres sur le sens sont centrales sont analysées dans cet article: la mutation à une organisation moins fusionnnée de l'usage des ressources, l'émergence de la propriété privée de puits et ses implications pour les droits fonciers, enfin l'utilisation matérielle et métaphorique des enclos dans une situation de droits conflictuels sur un terrain divise.
The politics of transporting
Authors: Peace Adrian 
Published: April 2006

Opening ParagraphThis paper describes the political organisation of transporting in Agege, a Nigerian town located on the northern boundary of Lagos. Its aim is to provide an anthropological interpretation of this important domain of modern entrepreneurship, for, while social anthropologists have increasingly studied African urban economies, the analysis of transportation remains the preserve of economists and geographers. When anthropologists do make mention of those who own vehicles geared to the movement of produce and passengers, their social and political significance is confirmed. Wealthy Hausa transporters emerge as key figures in Cohen's (1969) careful dissection of the Sabon Gari of Ibadan, while Peel (1983) details how those traders who were also transporting magnates exercised continuous influence in the political transformation of Ijesha throughout much of the present century. Despite such occasional commentaries, the organisation of transportingper seremains a field unexplored by anthropologists. Accordingly, it is the micropolitics of relationships between bus owners, drivers and conductors that constitute my major concern, although the analysis also leads to examining relationships between prominent transporters and those who exercise authority in the contemporary Nigerian state.
Thomas Decker and the death of Boss Coker
Authors: Shrimpton Neville 
Published: April 2006

Opening ParagraphThomas Alexander Leighton Decker,o.b.e., teacher, journalist, broadcaster, poet, dramatist, linguist and senior civil servant—to name only some of the major occupations or preoccupations of his busy life—was the man who, more than any other, crusaded for the acceptance of Krio as a language in its own right. At a time when others dismissed Sierra Leone's mainlingua francaas a debased or corrupt form of English and failed to recognise its distinct identity and full potential, Thomas Decker never once faltered in his conviction that it was as good a language as any other. He spent much of his life trying to convince others of the truth of this, and the fact that Krio has at last begun to gain the acceptance he sought for it is in no small measure due to him and his efforts on its behalf.
The loibon as sorcerer: a Samburu loibon among the Ariaal Rendille, 1973–87
Authors: Fratkin Elliot 
Published: April 2006

AbstractHistorical studies of the Maasailoibonokhave emphasised their ritual and political leadership, particularly during the inter-Maasai warfare of the nineteenth century. This study of a modern Samburuloibonillustrates that theloibon'sprimary activity i n non-crisis periods is the private performance of rituals of divination (nkidong) and the dispensation of protective medicines (ntasim) to combat acts of sorcery. Although the loibon will occasionally perform public divinations and protect communities from natural misfortune with ntasim, these activities are infrequent and secondary to his main role.Lekati Leaduma practisedntasimandnkidongamong the Ariaal Rendille of northern Kenya until his death in 1987, mainly among communities isolated from administrative centres with adequate medical care and police protection. This study analyses thenkidongandntasimof Leaduma as private curative rituals, and suggests historical and symbolic linkages and differences with other Samburu and Maasailoibonok. It is argued that, although Samburuloibonokaspire to leadership and moral authority, their association with sorcery and supernatural power isolates them as dangerous outsiders to moral Samburu society.
The dirty smith: smell as a social frontier among the Kapsiki/Higi of north Cameroon and north-eastern Nigeria
Authors: Beek Walter E. A. van 
Published: April 2006

AbstractAmong the Kapsiki/Higi of the Mandara mountains the division between black-smith and non-smith pervades society. Blacksmiths dominate technical and ritual specialisations—including the forge—and through their association with death are considered dirty. One way in which this opposition is expressed is through the definition of smell.Using ideophones, the Kapsiki distinguish fourteen types of smell, each associated with specific ‘smelly’ objects, animals or persons (i.e. blacksmiths). The definition of smells by blacksmiths, however, is different from that of non-smiths; also the women of both ‘castes’ define smell differently from the men. Whereas men use the definition of smell to accentuate the gap between smith and non-smith, the women tend to mediate the division.In Kapsiki culture smell is not associated with notions of evil or witchcraft. It is, however, tied in with burial, which in Kapsiki culture entails protracted exposure to a decomposing corpse. The connection smith-corpse may be one reason for the smelly definition of the smith. Another may be the notion of ambivalence and the tendency to draw strict dividing lines between social groups. Smell in Kapsiki seems to stress borderline situations and the mutual dependence of opposing groups.
The role of language in West African Islam
Authors: Brenner Louis , Last Murray 
Published: April 2006

Opening Paragraph‘A translation of the meaning of the Holy Koran into the Hausa language’ – this is the careful wording of the title of the work sponsored by the Jama'atu Nasril Islam (whose President is the Sultan of Sokoto) and signed by Abubakar Mahmoud Gummi, the chairman of its executive committee and former Grand Khadi (Gummi, 1980). It is, in short, as official a Muslim publication as there can be in Nigeria. The Arab text (set in a standard Beirutnaskhtypeface) is on the right of the page, the Hausa, in roman script (boko), on the left; yet colleagues say that the Hausa still reads as if it was simply part of an oral, abbreviated tafsiri transcribed for printing. Though it is nowhere labelled as tafsiri, it has some footnotes and a sentence introducing each sura; and it is a truly vernacular translation – that is, it is not as awkward to read as, say, the books translated by Haliru Binji into what one could best describe as ‘malamanci’. Lastly, the printed text originally was circulated in sections – in part, it is said, to assess people's reactions to a Hausa translation of the Holy Koran being sold in the streets of Nigerian cities. It is a measure of the public's acceptance of this work – which is in reality no more than a printed version of the various oral ‘translations’ one can hear every year in public, on the radio or on tape – that not merely has it now appeared as a single volume but that it has already gone into a second edition; indeed, Alhaji Nasiru Kabara has now almost completed the process of producing his own version.
Land expropriation and accumulation in the Sokoto periphery, Northwest Nigeria 1976–86
Authors: Swindell K. , Mamman A. B. 
Published: April 2006

Opening ParagraphIn 1976, Sokoto became the capital of the newly created Sokoto State, one of nineteen comprising Federal Nigeria. This caliphal city and former colonial provincial town subsequently experienced an exponential growth of population from some 80,000 to around 200,000 by 1980. The city expanded physically into the surrounding countryside and new buildings and infrastructures absorbed large areas of farmland, and encircled several villages. This urban advance into the countryside was exacerbated by the fact that it took place within a densely populated area of annual upland cultivation, dissected by tracts of dry-season irrigated floodland. Not surprisingly, access and rights to farmland have become highly charged and sensitive issues. The peripheries and hinterlands of many Nigerian towns have become arenas of conflict and change, where state expropriation and private accumulation have dispossessed and impoverished rural people. The state has taken over land for institutional use or agricultural development projects, while urban and rural capital have accumulated land for speculative building on the edges of cities and for farming within the surrounding countryside. The increased numbers of landless and, more important, the land-poor constitute new kinds and degrees of rural poverty.
Marriage rules on the Plateau: an exchange
Authors: Muller J. C. , Sharp Barrie 
Published: April 2006

In his recent review article (Sharpe, 1983) Barrie Sharpe submits two of my books (Muller, 1976, 1981) to dissection but he does so in such a carefree manner, with so many mistakes and gratuituous assumptions, that I am prompted to reply in order to set the record straight.I am first accused of not having dealt with ’religious conversion, social change and economy in [my] two books’. This is partly true forDu bon usage, and I have explained the reasons for not analysing the matrimonial changes brought about by British colonization (p. 28). It would have made too cumbersome a book and would have been beside the point. As forParenté et manage, I have dealt with ‘economy, social change and conversion’ (pp. 46–67 for economy; 99–100 on the changes in bridewealth payments for literate people; 138–40 about the introduction of reimbursement of bridewealth, for instance, but there are many more changes examined together with the influence of Christianity on marriage throughout the book). These aspects are also covered in three articles published separately: one on inter-tribal trade, another on conversion, and a third on economic change and tin mining, a topic also dealt with in the review article in question (Muller, 1972, 1974, 1980a).
The contextual significance of the charismatic movements in independent Nigeria
Authors: Ojo Matthews A. 
Published: April 2006

IntroductionThe emergence of the charismatic movements in Nigeria in the 1970s is a remarkable religious phenomenon. Their rapid growth and success could be attributed to many factors, but the central factor which clearly emerges is that the movements have been presented in a manner acceptable and relevant to Nigerians, and they have been adapted to the situation in Nigeria. The continuous growth of the movements into the 1980s suggests that they are acting as responses to certain areas of need in Christian commitment in Nigeria. The concept of contextualisation is therefore the major key to an understanding of their rapid growth. Were it not for their contextualisation, the movements might have crystallised without any growth or might even have condemned themselves to decline and dissolution.
State intervention and commodity production in Ugogo: a historical perspective
Authors: Thiele G. 
Published: April 2006

IntroductionDuring the 1970s the Tanzanian state moved a very substantial part of the rural population into nucleated settlements. This was followed by the setting up of new village institutions. It was villagization in a double sense: the creation of physical ‘villages’ from dispersed households and the establishment of corporate ‘villages’ (more precisely, village councils) intended to regulate the activities of those households. It was an intervention officially justified as a means of increasing collective consumption (through the provision of health care, schools and other services) and simultaneously of transforming an essentially traditional hoebased agricultural system (by facilitating the use of modern inputs). External commentators have seen it either as a large scale example of misguided bureaucratic practice (Coulson, 1977) or as part of a process of state expansion intended to increase control over peasant production (Bernstein, 1981; Hyden, 1980). My objective here is not to provide another theoretical commentary, but to show that ultimately any overall assessment of the impact of villagization must rest upon detailed analyses of particular local economies. I have restricted my discussion of this impact to household production.
‘Caste’ in Africa: the evidence from south-western Ethiopia reconsidered
Authors: Pankhurst Alula 
Published: April 2006

AbstractThis article questions the prevalent use of the ‘caste’ concept to describe marginalised occupational minorities in the south-western Ethiopian context. Three types of objection are discussed: ideological, genetic and structural, relating to cultural, historical and social factors respectively. In ideological terms, marginalisation is generally not justified through a coherent religious philosophy; myths are often absent, are seldom elaborate and do not explain adifferentialranking of occupational groups. Notions of pollution are prevalent and usually presented in the dominant idiom of food transgressions; but the farming majority is not considered pure. In genetic terms, none of the existing models explains the origins of all marginalised groups. Whereas the ‘remnants’ model is largely discredited, and the ‘internal differentiation’ model currently favoured, this article emphasises the importance of migration, which is intimately linked with non-farming occupations as well as with marginalised and minority statuses. The lack of a single cross-culturally valid model, combinations of explanations, and differences among various types of occupational groups within and between groups, all militate against a ‘caste’ interpretation of the origins of marginalised groups in south-western Ethiopia. In structural terms ‘caste’ is not used for the farming majority but only for minority craftsmen and hunters. However, the argument that relations between the marginalised and the dominant groups are based on dyadic patron-client relations does not invalidate the clear structural political, economic and social marginalisation. As for the argument that the marginalised form a single undifferentiated bloc, it is suggested that, though strict hierarchies are rare, endogamy makes for differentiation. Rather than a lack of ranking, spatial variations and changes over time deserve explanation; this suggests that one cannot speak of a coherent organisational principle such as one would expect to find in ‘caste’ societies. It is concluded that the lack of a uniform ideological cultural underpinning, the complex and varied origins and processes of marginalisation, and the specific structural relations between the majority and the dominated groups, all suggest that the ‘caste’ concept is of minimal analytical value and is therefore best left to the Indian context. A better understanding of marginalisation can start by analysing different local conceptions, and how endogamy structures differentiation and is related to occupation. A clearer analysis of marginalisation processes would mean tracing migrations, competition for resources and changing technological, economic, social and cultural relations between craft producers and dominant groups and interactions across ethnic boundaries.
Dagara bagr: ritualising myth of social foundation
Authors: Tengan Alexis B. 
Published: April 2006

AbstractThe article explores the ritualising processes of a myth of social foundation, the bagr myth, among the Dagara of north-west Ghana and south-west Burkina Faso. It describes how rituals form part of the daily life of the Dagara and shows how bagr rituals form a series of private and public events lasting the whole year or the bagr season. The article describes the social life in the neighbourhood within which most ritual activities take place and outlines the historical events which are possibly responsible for the creation of the bagr myth itself as a narrative text. The rest of the article is devoted to the ritualising processes of the bagr myth. Much of the article, particularly this section, is structured around the author's own experiences and participant observation of ritual activities. The aim is to show why the public rituals of bagr are not about initiating particular individuals into a secret society or lodges but are about how Dagara society constitutes itself. The day and night ritual narration of the bagr myth involving different segments of society and described in detail in the second half of the article seems to justify this claim. The article includes excerpts from bagr narratives recorded by the author to illustrate how the text is being constructed and the sort of information it is intended to communicate.