Araya Asfaw

Moringa stenopetala seed oil as a potential feedstock for biodiesel production in Ethiopia

Moringa stenopetala seed oil was evaluated as a potential sustainable feedstock for biodiesel production in Ethiopia. Base catalyzed transesterification of M. stenopetala seed oil was carried out with methanol, ethanol and a mixture of methanol and ethanol (1:1 molar ratios) with an alcohol to oil molar ratio of 6:1. The physiochemical characteristics of the esters were assessed to evaluate their suitability for use in standard diesel engines. The study indicated that M. stenopetala seeds yield 45% w/w of oil. The oil contains 78% mono-unsaturated fatty acid and 22% saturated fatty acid. Oleic is the dominant fatty acid, about 76%. When mixtures of alcohols were used, the amount of ethyl ester formed was 30% that of methyl ester. The physicochemical properties of M. stenopetala oil methyl ester and mixture of esters (methyl and ethyl) were found to comply with both the American ASTM D6751 and the European standard EN 14214. Overall, the physicochemical properties of the ester mixture of M. stenopetala oil were better than that of methyl ester. The recommended way to use the oil as a fuel is as a mixture of esters. The study indicates that compared to biodiesel fuels derived from other vegetable oils, M. stenopetala has a number of advantages. Furthermore, the use of M. stenopetala seed oil for the production of biodiesel will not compete with food as neither the seeds nor the oil are used for food in Ethiopia.

Sustainable Household Energy for Addis Ababa, Ethiopia

This paper presents the household energy consumption trends and alternatives for Addis Ababa, Ethiopia. The study shows that, during the decade that the study was conducted, household energy consumption per capita increased by 17% from 6GJ. Traditional fuels accounted for about 80% of the consumption. Household energy expenditure per person tripled from

X-RAY LASER PHOTOPUMPED RESONANCE FLUORESCENCE

10 to

Power in participatory processes: reflections from multi-stakeholder workshops in the Horn of Africa

30. The energy consumption trend is highly correlated with fuel price; in 1995, charcoal was the most expensive fuel (

A fast method of modeling spectral lines

7 per GJ), followed by LPG and electricity (

Electronic environmental governance in Ethiopia: key thrust areas

5 per GJ). Kerosene was sold at about half the price of charcoal, while fuelwood was the least expensive (

Shift and broadening of Na D lines at low pressure

1 per GJ). In 2005, charcoal prices increased by about 20%, while fuelwood price declined by more than 10%. The price of electricity doubled while that of kerosene tripled and LPG quadrupled. Despite the rise in price, electricity consumption shot up by a factor of twenty, and kerosene declined by half. During the decade, traditional fuel use increased by 10% while modern energy use increased by 50%. The paper also considers the potential explanations and policy implications of the trends in the data.

Measurement of caffeine in coffee beans with UV/vis spectrometer

Abstract A calculation of the resonance fluorescence spectrum of the 146.526 A 3d-2p transition of fluorine-like magnesium photopumped by the 146.515 A zirconium X-ray laser line is discussed in connection with an experimental measurement in a hot, dense laser produced plasma. The calculation of the fluorescence spectral profile is based on a recent extension of the Frequency Fluctuation Model (FFM) that enables the computation of radiative redistribution and other higher order radiative processes. The discussion of the photopumping experiment includes an analysis of the optimal plasma conditions and the associated characteristics of the redistributed radiation with specific reference to the experimental feasibility. The potential information to be acquired in the comparison of the computational and experimental results also will be considered.

Investigation of Waste Coffee Ground as a Potential Raw Material for Biodiesel Production

The sustainability science literature views the participation of local stakeholders as a necessary element for both conducting transdisciplinary research and implementing sustainable development projects. However, there is very little critical reflection on how power dynamics between researchers and local stakeholders affect the success of participatory processes. This article draws on the critical tradition of political science and sociology to examine how power dynamics are inherent to, and should always be a concern during, participatory processes. This also applies for sustainability science research and the implementation of sustainable development projects, especially in developing contexts such as those of Africa. While local participation enhances the voices of local stakeholders, power dynamics between them and the researchers driving these processes can dampen local voices or elide critical pieces of information. Using evidence from participatory workshops in Djibouti and Kenya, we demonstrate that these power dynamics can unintentionally exclude critical knowledge and perspectives from the formal proceedings of participatory workshops, despite an express focus on stakeholder inclusion and participatory methods. Using Steven Lukes’ tripartite conception of power, we elicit how the workshop structure and the actions of researchers as the designers and facilitators of the workshop may have prevented the emergence of this critical information. The central argument is that reflecting on power will help researchers and practitioners identify the power dynamics inherent in the participatory processes so they can work to overcome them. Such self-reflection can strengthen sustainability science and practice in African and other contexts.

Potential of Bioethanol Production and Optimization Test from Agricultural Waste: The Case of Wet Coffee Processing Waste (Pulp)

Abstract A fast method of modeling spectral lines is presented. The method utilizes a new approach in generating the Voigt profile using MathematicaTM. As an example, we consider the hydrogen Rydberg transition lines from the ground state to excited states of n=32, 33, 34, 35 and 36 at 91.2 nm . Using a Fast Fourier Transform (FFT) method, the observed spectrum is obtained by convoluting the true spectrum with the slit function with a resolution that is twice the Doppler widths of the lines. Furthermore, the true spectrum is deconvoluted from the observed spectrum and is compared with the true transmission. Simulations of an absorption experiment observed with instrumental resolution equal to the Doppler widths and one-half the Doppler width are shown.