The Fundamental Word of Christ's Eschatological Proclamation : Karl Barth on the Beatitudes

Open Access via the Brill AgreementPeer reviewedPublisher PD

European Union enlargement

Not availabl

Measurement of the Effect of Policy Changes on Volatility in Dairy Markets1

Volatility in dairy commodity markets has become a major concern for many in the dairy supply chain and is likely to remain so in the future. Changes to the Common Agricultural Policy (CAP) over the past decade have more closely aligned EU and World prices and their associated volatilities. The aim of this paper is to measure volatility at farm level in Ireland over time, identify possible reasons for the increased volatility and identify ways of reducing volatility. Statistical measures such as coefficient of variation (CV) and annualised standard deviation are used to provide measures of past volatility and its evolution over time. Family Farm Income (FFI) data, input data and farm gate milk prices are used to highlight historical farm level volatility. As farm level prices should be based on dairy commodity returns, the links between these prices and the farm gate prices are explored. Monthly wholesale prices for Skim Milk Powder (SMP), whole milk powder (WMP), and butter between January 1997 and March 2012 are used for this analysis. The time period is divided into two sub periods to quantify changes in volatility pre and post the Luxembourg Agreement. The results highlight that both commodity price and farm gate volatility has increased dramatically post 2007. Volatility will become a more inherent part of the dairy industry as policy changes cause prices to become further aligned with world prices. The findings of this research highlight that risk management strategies are desirable for the long term success of the dairy industry

Self-assembled arrays of ZnO nanoparticles and their application as varistor materials

Linear arrays of ZnO nanoparticles have been successfully prepared by a simple sol–gel condensation reaction involving chemical modifiers, followed by drying (80oC) and calcination (500 oC). The calcined material (nanoarray ZnO) is composed of approximately spherical nanoparticles of average diameter 21+/-3 nm, selfassembled to form arrays extending in length to 2–4 mm. The morphology of the ZnO is found to depend sensitively on the amounts of chemical modifiers present. In their absence the ZnO produced (nano-ZnO) is an unstructured agglomerate of nanoparticles. The mechanism for formation of these linear arrays has been investigated by examining the intermediates formed at 80 oC and 250 oC using XRD and TEM and by following the decomposition reactions using TGA and DSC. Varistors prepared from the nano-array ZnO by sintering (1050 oC) with ppropriate mixtures of metal oxides showed a breakdown voltage of 786 +/- 30 Vmm-1, which is substantially higher than that of samples prepared under similar conditions from either micronsized commercial ZnO (507 +/-30 V mm-1) or from nano-ZnO (683 +/-30 V mm-1)

Overcoming the supply inconsistencies of tidal current energy conversion devices

The adoption of a sustainable approach to meeting the energy needs of society has recently taken on a more central and urgent place in the minds of many people. There are many reasons for this including ecological, environmental and economic concerns. One particular area where a sustainable approach has become very relevant is in the production of electricity. The contribution of renewable sources to the energy mix supplying the electricity grid is nothing new, but the focus has begun to move away from the more conventional renewable sources such as wind and hydro. The necessity of exploring new and innovative sources of renewable energy is now seen as imperative as the older forms (i.e. hydro) reach the saturation point of their possible exploitation. One such innovative source of energy currently beginning to be utilised in this regard is tidal energy.\ud The purpose of this thesis is to isolate one specific drawback to tidal energy, which could be considered a roadblock to this energy source being a major contributor to the Irish national grid. This drawback presents itself in the inconsistent nature in which a tidal device generates energy over the course of a 24 hour period. This inconsistency of supply can result in the cycling of conventional power plants in order to even out the supply, subsequently leading to additional costs.\ud The thesis includes a review of literature relevant to the area of tidal and other marine energy sources with an emphasis on the state of the art devices currently in development or production.\ud The research carried out included tidal data analysis and manipulation into a model of the power generating potential at specific sites. A solution is then proposed to the drawback of inconsistency of supply, which involves the positioning of various tidal generation installations at specifically selected locations around the Irish coast. The temporal shift achieved in the power supply profiles of the individual sites by locating the installations in the correct locations, successfully produced an overall power supply profile with the smoother curve and a consistent base load energy supply. Some limitations to the method employed were also outlined, and suggestions for further improvements to the method were made

Self-assembled arrays of ZnO nanoparticles and their application as varistor materials

Linear arrays of ZnO nanoparticles have been successfully prepared by a simple sol–gel condensation reaction involving chemical modifiers, followed by drying (80oC) and calcination (500 oC). The calcined material (nanoarray ZnO) is composed of approximately spherical nanoparticles of average diameter 21+/-3 nm, selfassembled to form arrays extending in length to 2–4 mm. The morphology of the ZnO is found to depend sensitively on the amounts of chemical modifiers present. In their absence the ZnO produced (nano-ZnO) is an unstructured agglomerate of nanoparticles. The mechanism for formation of these linear arrays has been investigated by examining the intermediates formed at 80 oC and 250 oC using XRD and TEM and by following the decomposition reactions using TGA and DSC. Varistors prepared from the nano-array ZnO by sintering (1050 oC) with ppropriate mixtures of metal oxides showed a breakdown voltage of 786 +/- 30 Vmm-1, which is substantially higher than that of samples prepared under similar conditions from either micronsized commercial ZnO (507 +/-30 V mm-1) or from nano-ZnO (683 +/-30 V mm-1)

High Performance ZnO Varistors Prepared From Nanocrystalline Precursors for Miniaturised Electronic Devices

An industrially viable solution-based processing route using minimal amounts of solvent has been used to prepare bulk quantity nanopowders (average particle size 15.3 nm) for the fabrication of ZnO varistors. The xerogels, calcined powders and sintered materials were fully characterised. The preparation of varistors from nanopowders has been optimised by studying the effect of temperature on grain growth, densification and breakdown voltage. The varistors are prepared by sintering at 1050 C for 2 hours, a temperature that is significantly lower than that used in the current industrial process. Highly dense varistor discs prepared from the sintered material produce devices, with a breakdown voltage 85% higher than that of commercial varistors, making them suitable for use in miniaturised electronic circuitry. Improved performance of these materials has been attributed to the small grain size and better dispersion of additives on ZnO grains

Advances in the synthesis of ZnO materials for varistor devices

ZnO based varistors are widely used for overvoltage protection in many electrical and electronic circuits, at voltages ranging from a few to over a million volts. By careful control of the microstructure, through nanostructuring by chemical routes, it should be possible to produce varistors with high breakdown voltage (Vc), as this is proportional to the number of active grain boundaries in the sintered body. This property is particularly important for the production of the small-sized varistors needed for modern electronic instruments such as tablet computers and mobile phones. The current review will outline the recent advances in the chemical processing (e.g. sol–gel, combustion synthesis plasma pyrolysis, micro-emulsion synthesis and precipitation routes) of varistors from ZnO nanomaterials and the properties of these materials. Uncontrolled grain growth at higher temperature is highlighted as a major challenge for obtaining desirable electrical properties for nano-varistors. Various novel sintering techniques such as step-sintering, spark plasma and microwave sintering methods are expected to deliver a varistor with controlled grain growth and optimum electrical characteristics