Hydrogen fuel cells are likely to begin replacing conventional internal combustion engines as a power generation method for transportation applications in the near future. A life cycle analysis of a hydrogen fuel cell was performed to examine the major environmental impacts of such an engine in comparison with an internal combustion engine. To quantify the emissions, material consumption and energy consumption were identified by carrying out mass and energy balances, respectively. Wherever possible, a “well-to-wheel” approach was adopted to identify all (...) the processes involved. The size of the hydrogen fuel cell engine selected was 60 kW, which would power a small automobile weighing around 800 kg. This report briefly describes the materials and processes involved in assembling such an engine, with their respective environmental impacts. Different technologies to build a hydrogen economy also are discussed because hydrogen is an integral part of most fuel cell engines. The main conclusion is that if an environmentally sustainable system of hydrogen production is found, the use of hydrogen and, in turn, hydrogen fuel cell cars would be highly beneficial. Thus, the theoretical potential of fuel cells is great for environmental benefits, but practical applications might prove otherwise. (shrink)

The realization of dwindling fossil fuel supplies and their adverse environmental impacts has accelerated research and development activities in the domain of renewable energy sources and technologies. Global energy demand is expected to rise during the next few decades, and the majority of today's energy is based on fossil fuels. Alternative energy sources and technologies can play a vital role in lowering or eliminating our reliance on fossil fuels. However, such a transition will require a large investment and will not (...) be reversible. The benefits of hydrogen and other liquid fuels as transportation fuels are not marginal, but the real urgency in greenhouse gas reductions and fossil fuel replacement should not be translated into an energy infrastructure based on unsustainable sources in the long run. It is wise to examine each option thoroughly and objectively now and discard those with little potential so our focus and effort may be placed elsewhere. (shrink)

Studies regarding rural entrepreneurs in developing countries and, specifically, their well-being have not been sufficiently developed in the literature. The present study was an attempt to fill this gap and to examine important antecedents and outcomes associated with entrepreneurial well-being among a sample of 102 Iranian rural entrepreneurs. This research established a theoretical research model that highlighted the relationships among job fit, entrepreneurial passion, well-being, and persistence. The results of structural equation modeling supported the hypothesized model. In particular, the results (...) indicated that higher job fit was associated with higher levels of entrepreneurial well-being through an entrepreneurial passion mechanism. Moreover, the results supported the hypothesized serial mediating effect. In other words, a high level of job fit enhances entrepreneurial persistence through a high level of entrepreneurial passion and well-being. This study provides significant input to policymakers and practitioners in their efforts to promote the antecedents and outcomes of well-being among rural entrepreneurs. (shrink)

Religiosity is one of the most prominent and extensive social factors influencing one’s behavior; however, there is a lack of research analyzing the religiosity impact on pro-environmental behavior, particularly for women in rural areas. To narrow the research gap, this study established a theoretical research model by incorporating religiosity into the Theory of Planned Behavior to explore factors affecting rural female facilitators’ pro-environmental behavior. The extended Theory of Planned Behavior model was consequently tested by empirical data collected from 110 rural (...) female facilitators in Qom Province in the center of Iran. The results of structural equation modeling indicated that subjective norms and environmental attitude were positively and significantly related to pro-environmental intentions. In addition, pro-environmental intentions and perceived behavioral control were found to be significantly associated with pro-environmental behaviors. The results revealed that there was a direct and indirect relationship between religiosity and pro-environmental behaviors via perceived behavioral control. In addition, there was an indirect relationship between religiosity and pro-environmental intentions via subjective norms and environmental attitudes. Therefore, this study revealed that religiosity as social pressure plays an important role in determining pro-environmental intentions and behaviors among rural female facilitators in Iran. Thus, in order to promote pro-environmental behavior, the religiosity aspects should be considered and people should be stimulated to act in a more environmentally friendly mode via religious prism. (shrink)

Greenhouse gas emissions are adversely affecting the earth’s climate, a global common and a public good. The contribution of individual countries has a limited effect on the biosphere, implying that only globally coordinated efforts may result in significant climate improvements. The Rio Earth Summit (1992) and Kyoto Protocol (1997) are manifestations of international efforts to achieve sustainable development through efficient use of energy and incorporating more renewable sources in global economy. In this article, the author examines the energy-related emissions of (...) greenhouse gases and the utilization of renewable energy sources in Canada with respect to Agenda 21 commitments. An overview of the results of Canada’s policies on climate change since Rio in terms of energy consumption, various sources of energy, and emission rates of greenhouse gases is also presented. It is concluded that the current plans of the Canadian government to deal with greenhouse gas emissions have not been effective. (shrink)

Word Order and Scrambling introduces readers to recent research into the linguistic phenomenon called scrambling and is a valuable contribution to the fields of ...

In some cases, Avicenna used the semantical premises in order to deduce some conclusions in his Physics. For instance, he analyzes five derivatives of the word “tabiat” and then in the light of these analyses, he concludes that the natural properties of an object are caused by its essence and are based on it. Here, the major problem is how to justify Avicenna's passage from semantical premises to physical consequents. This paper shows that through analyzing the relation between nature and (...) its derivatives, on one hand, and explicating Avicenna’s definition of the “nature” on the other hand, we can defend the rationality of such a passage. (shrink)