Catalysts in production of biodiesel:a review

Biodiesel is a renewable substitute fuel for petroleum diesel fuel which is made from nontoxic, biodegradable, renewable sources such as refined and used vegetable oils and animal fats. Biodiesel is produced by transesterification in which oil or fat is reacted with a monohydric alcohol in the presence of a catalyst. The process of transesterification is affected by the mode of reaction, molar ratio of alcohol to oil, type of alcohol, nature and amount of catalysts, reaction time, and temperature. Various studies have been carried out using different oils as the raw material and different alcohols (methanol, ethanol, butanol), as well as different catalysts, notably homogeneous ones such as sodium hydroxide, potassium hydroxide, sulfuric acid, and supercritical fluids or enzymes such as lipases. Recent research has focused on the application of heterogeneous catalysts to produce biodiesel, because of their environmental and economic advantages. This paper reviews the literature regarding both catalytic and noncatalytic production of biodiesel. Advantages and disadvantages of different methods and catalysts used are discussed. We also discuss the importance of developing a single catalyst for both esterification and transesterification reactions.

Backlund-Darboux Transformations in Sato's Grassmannian

We define Bäcklund–Darboux transformations in Sato’s Grassmannian. They can be regarded as Darboux transformations on maximal algebras of commuting ordinary differential operators. We describe the action of these transformations on related objects: wave functions, tau-functions and spectral algebras.

Organizational, systems and human issues in production planning, scheduling and control

With global markets and global competition, pressures are placed on manufacturing organizations to compress order fulfillment times, meet delivery commitments consistently and also maintain efficiency in operations to address cost issues. This chapter argues for a process perspective on planning, scheduling and control that integrates organizational planning structures, information systems as well as human decision makers. The chapter begins with a reconsideration of the gap between theory and practice, in particular for classical scheduling theory and hierarchical production planning and control. A number of the key studies of industrial practice are then described and their implications noted. A recent model of scheduling practice derived from a detailed study of real businesses is described. Socio-technical concepts are then introduced and their implications for the design and management of planning, scheduling and control systems are discussed. The implications of adopting a process perspective are noted along with insights from knowledge management. An overview is presented of a methodology for the (re-)design of planning, scheduling and control systems that integrates organizational, system and human perspectives. The most important messages from the chapter are then summarized.

A Plan for Salisbury, MD: Urban Design Transformations in Response to Sea Level Rise

This thesis proposes a master plan for Salisbury, MD that presents solutions to the challenges faced by small towns along tidal waterways. Salisbury’s challenges include flooding and sea level rise, poorly defined arteries framing downtown and disconnecting neighborhoods, and a lack of vibrant, mixed use development. These issues are common to small towns and present opportunities for transformative design.

The new Hollywood, 1981–1999: special/visual effects

The emergence and development of digital imaging technologies and their impact on mainstream filmmaking is perhaps the most familiar special effects narrative associated with the years 1981-1999. This is in part because some of the questions raised by the rise of the digital still concern us now, but also because key milestone films showcasing advancements in digital imaging technologies appear in this period, including Tron (1982) and its computer generated image elements, the digital morphing in The Abyss (1989) and Terminator 2: Judgment Day (1991), computer animation in Jurassic Park (1993) and Toy Story (1995), digital extras in Titanic (1997), and ‘bullet time’ in The Matrix (1999). As a result it is tempting to characterize 1981-1999 as a ‘transitional period’ in which digital imaging processes grow in prominence and technical sophistication, and what we might call ‘analogue’ special effects processes correspondingly become less common. But such a narrative risks eliding the other practices that also shape effects sequences in this period. Indeed, the 1980s and 1990s are striking for the diverse range of effects practices in evidence in both big budget films and lower budget productions, and for the extent to which analogue practices persist independently of or alongside digital effects work in a range of production and genre contexts. The chapter seeks to document and celebrate this diversity and plurality, this sustaining of earlier traditions of effects practice alongside newer processes, this experimentation with materials and technologies old and new in the service of aesthetic aspirations alongside budgetary and technical constraints. The common characterization of the period as a series of rapid transformations in production workflows, practices and technologies will be interrogated in relation to the persistence of certain key figures as Douglas Trumbull, John Dykstra, and James Cameron, but also through a consideration of the contexts for and influences on creative decision-making. Comparative analyses of the processes used to articulate bodies, space and scale in effects sequences drawn from different generic sites of special effects work, including science fiction, fantasy, and horror, will provide a further frame for the chapter’s mapping of the commonalities and specificities, continuities and variations in effects practices across the period. In the process, the chapter seeks to reclaim analogue processes’ contribution both to moments of explicit spectacle, and to diegetic verisimilitude, in the decades most often associated with the digital’s ‘arrival’.

The transformation of the North American apparel industry: is NAFTA a curse or a blessing?

Includes bibliography

Resistência e reafirmação camponesa: transformações e permanências na agricultura no município de Faina/GO

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

(Des)ordenamientos territoriales salteños : Una aproximación al contexto previo al Ordenamiento Territorial de Bosques Nativos en la provincia de Salta

En este artículo indagamos en las características productivas de la provincia de Salta en los años previos a la sanción de la Ley Nacional No. 26.331 de "Presupuestos Mínimos de Protección Ambiental de los Bosques Nativos" y de la puesta en marcha del Ordenamiento Territorial de Bosques Nativos. Luego de reseñar las transformaciones en el agro que desde inicios de la década de 1970 tienen lugar en la Argentina, avanzamos en la caracterización del proceso y sus particularidades en el este salteño, en donde en las últimas décadas se ha dado un rápido avance de la frontera agropecuaria por sobre territorios antes marginales para la producción agrícola y ganadera empresarial

(Des)ordenamientos territoriales salteños : Una aproximación al contexto previo al Ordenamiento Territorial de Bosques Nativos en la provincia de Salta

En este artículo indagamos en las características productivas de la provincia de Salta en los años previos a la sanción de la Ley Nacional No. 26.331 de "Presupuestos Mínimos de Protección Ambiental de los Bosques Nativos" y de la puesta en marcha del Ordenamiento Territorial de Bosques Nativos. Luego de reseñar las transformaciones en el agro que desde inicios de la década de 1970 tienen lugar en la Argentina, avanzamos en la caracterización del proceso y sus particularidades en el este salteño, en donde en las últimas décadas se ha dado un rápido avance de la frontera agropecuaria por sobre territorios antes marginales para la producción agrícola y ganadera empresarial

(Des)ordenamientos territoriales salteños : Una aproximación al contexto previo al Ordenamiento Territorial de Bosques Nativos en la provincia de Salta

En este artículo indagamos en las características productivas de la provincia de Salta en los años previos a la sanción de la Ley Nacional No. 26.331 de "Presupuestos Mínimos de Protección Ambiental de los Bosques Nativos" y de la puesta en marcha del Ordenamiento Territorial de Bosques Nativos. Luego de reseñar las transformaciones en el agro que desde inicios de la década de 1970 tienen lugar en la Argentina, avanzamos en la caracterización del proceso y sus particularidades en el este salteño, en donde en las últimas décadas se ha dado un rápido avance de la frontera agropecuaria por sobre territorios antes marginales para la producción agrícola y ganadera empresarial