An experimental apparatus for testing biodiesels based on a CFR engine—setup and validation with different methyl ester blends

A cooperative fuel research (CFR) engine was modified and instrumented in order to control operating conditions and to measure engine parameters and in-cylinder pressure diagrams. Aiming at the comparison of different alternative fuels, an experimental procedure was defined, including cetane number (CN) evaluation and the definition of engine operating quantities in different working points, for fixed levels of compression ratio (CR) and injection advance. An investigation was made considering several blends of methyl-esters of rapeseed oil (RME) and of a mix of vegetable oils (VOME) with conventional diesel oil. The defined experimental procedure was applied to assess CN, engine brake thermal efficiency (bte) and exhaust emissions. Results show that the biodiesel content has a positive influence on soot emissions, with strong reduction, while thermal efficiency and NO_X emissions are negatively affected, which can be justified taking into account fuel properties and changes in combustion process. As observed outcomes are generally in line with those presented in literature, the facility proved to be a suitable tool for basic investigations on alternative fuels to be used in specific applications.     

College and university environmental programs as a policy problem (part 1): integrating knowledge, education, and action for a better world?

The environmental sciences/studies movement, with more than 1000 programs at colleges and universities in the United States and Canada, is unified by a common interest??ameliorating environmental problems through empirical enquiry and analytic judgment. Unfortunately, environmental programs have struggled in their efforts to integrate knowledge across disciplines and educate students to become sound problem solvers and leaders. We examine the environmental program movement as a policy problem, looking at overall goals, mapping trends in relation to those goals, identifying the underlying factors contributing to trends, and projecting the future. We argue that despite its shared common interest, the environmental program movement is disparate and fragmented by goal ambiguity, positivistic disciplinary approaches, and poorly rationalized curricula, pedagogies, and educational philosophies. We discuss these challenges and the nature of the changes that are needed in order to overcome them. In a subsequent article (Part 2) we propose specific strategies for improvement.     

Legalizing markets and the consequences for poaching of wildlife species: the vicuña as a case study

Vicuña provide an excellent case study for examining the sustainable use of wildlife outside protected areas: the community-based conservation approach. Vicuña populations in the high Andes of Argentina, Bolivia, Chile, Ecuador and Perú fell to a critically low level, but a Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) ban on trade in their fiber has seen numbers recover dramatically, and now live shearing of vicuña for a high-value international market is being promoted as a mechanism to secure both sustainable vicuña populations and local livelihoods. We used a dynamic optimization model to explore the consequences of legalizing markets, including the consequences for poaching which is critical in vicuña dynamics. Using parameters obtained from the literature and expert knowledge, we explored different scenarios for the Argentine region of Cieneguillas. Our results showed that the role of the international market is ambiguous; live shearing for an international market can provide the very best of outcomes for both vicuña and local people, with large herds generating high revenues. But an international market also creates a market for poached vicuña fiber; as a result, vicuña numbers risk once again falling to critically low levels, resulting also in minimal revenues from sale of fiber. The message for the international community is that if community-based conservation is not implemented carefully then its impact can easily be perverse.     

A review on the production of fermentable sugars from lignocellulosic biomass through conventional and enzymatic route—a comparison

The scarcity of fossil fuels has urged the economically developed countries to find the resources for an alternative energy sources. In apprehension to this, biofuels, like bioethanol and biobutanol, produced from lignocellulosic biomass were considered as potential alternative. There are several methods for the pretreatment of biomass before it is being used as a feedstock for the production of fermentable sugars. However, one of the crucial concerns here is to enumerate an economic pretreatment scheme that can be implemented in large scale for the production of mostly exposed cellulosic part from biomass. This will ensure an effective hydrolysis of cellulose for the production of fermentable sugars and the production of biobutanol from these derived sugars. Moreover, the keynote understanding of an effective fermentation is the production of less inhibitory compounds like furfural, hydroxymethyl furfural during the hydrolysis of cellulose. Enzymatic hydrolysis of cellulose was reported as the most efficient method is this aspect. Trichoderma sp. was found the mostly used resources for the enzyme called cellulase and Aspergillus sp. for hemicellulase enzymes. The most crucial part here is the isolation of proper enzyme that will increase the rate of hydrolysis. Moreover, selection of proper pretreatment process will be a key benefit to the production of fermentable sugars through enzymatic hydrolysis. Based on the biomass nature, the evaluated hot water pretreatment followed by enzymatic hydrolysis with a provision of enzyme reusability (like encapsulated or enzyme separation with membrane) seems to be promising for enhanced biofuel-production.     

Predicted uranium and radon concentrations in New Hampshire (USA) groundwater—Using Multi Order Hydrologic Position as predictors

Two radioactive elements, uranium (U) and radon (Rn), which are of potential concern in New Hampshire (NH) groundwater, are investigated. Exceedance probability maps are tools to highlight locations where the concentrations of undesirable substances in the groundwater may be elevated. Two forms of statistical analysis are used to create exceedance probability maps for U and Rn in NH groundwater. The first, Boosted Regression Tree (BRT), was selected for estimating U exceedance values. It computes exceedance values directly using the Bernoulli distribution function. The second method of statistical analysis used for Rn to determine exceedance probabilities is ordinary least squares (OLS) regression. In the process of determining exceedance probabilities for U and Rn, the utility of a new dataset is investigated. That new predictor dataset is the Multi-Order Hydrologic Position (MOHP) dataset. MOHP raster datasets have been produced nationally for the conterminous United States at a 30-m resolution. The concept behind MOHP is that, for any given point on the earth's surface, there is the potential for a longer groundwater flow path as one goes deeper beneath the land surface. MOHP predictors were tested in both models. Three MOHP predictors were found useful in the BRT model and two in the OLS model. MOHP data were found useful as predictors along with other site characteristics in predicting U and Rn exceedance probabilities in New Hampshire groundwater.     

Energy and exergy analysis of a solid-oxide fuel cell power generation system for an aerial vehicle (ISSA- 2015–139)

This paper presents the performance of the solid-oxide fuel cell/gas turbine hybrid power generation system with heat recovery waste unit based on the energy and exergy analyses. The effect of air inlet temperature and air/fuel ratio on exergy destruction and network output is determined. For the numerical calculations, air inlet temperature and air fuel ratio are increased from 273 to 373 K and from 40 to 60, respectively. The results of the numerical calculations bring out that total exergy destruction quantity increases with the increase of air inlet temperature and air/fuel ratio. Furthermore, the maximum system overall first and second law efficiencies are obtained in the cases of air inlet temperature and air/fuel ratio equal to 273 K and 60, respectively, and these values are 62.09% and 54.91%.     

More than just linking the nodes: civil society actors as intermediaries in the design and implementation of payments for ecosystem services–the case of a blue carbon project in Costa Rica

While in many cases the benefits of ecosystem services (ES) can be enjoyed on different scales, the provision of ES requires engagement and commitment at the local scale. Therefore, the local level becomes important when thinking about compensation schemes or payments for ecosystem services (PES) as an approach to managing ES. The difficult task of bringing together different actors and institutions at different scales for specific conservation projects at the local level often remains in the hands of intermediaries. In this paper, we investigate the role of a civil society organisation (CSO) as an intermediary organisation in a PES scheme, the Community Blue Carbon Project (CBCP) in Costa Rica. To assess the role of intermediaries in a PES scheme, we rely on social network analysis and examine the position and role of the intermediary organisation. Based on Net-Map interviews, which is an interview-based mapping tool that helps people understand, visualise, discuss and improve situations in which many different actors influence outcomes, we find that the intermediary organisation in the CBCP is composed of several institutional and individual intermediaries who create both formal networks for connecting the international to the local level and informal networks for creating trusting relationships among the actors. Different spatial levels are reflected within the CSO’s organisational structure, and the CSO mitigates the distributional, procedural, recognition and contextual aspects of environmental justice.     

Overcoming environmental deterioration through defensive expenditures: field evidence from Bahía del Tóbari (Sonora, México) and implications for coastal impact assessment

The costs of the maneuvers that fishermen and shrimp farmers have to undertake in a coastal scenario where both the access to navigable waters and water quality have decreased were interpreted as defensive expenditures. Maneuvers were prompted by profound changes in water circulation and siltation mode imposed by major shifts in regional and local land-use patterns. In coastal scenarios under heavy land-based discharges and local geomorphic modifications, local users with little chance to move away may modify their routines in order to maintain existing levels of utility. The concept of defensive expenditures could be used to assess social responses to adverse changes in environmental and resource conditions, as a means to distinguish stages in which local sectors respond individually from qualitatively different stages in which intersectoral events are more conspicuous.