Esterification reaction is most important reaction in biodiesel production. In this study, oleic acid was used as a suggested feedstock to study and simulate production of biodiesel. Batch esterification of oleic acid was carried out at operating conditions; temperature from 40 to 70 °C, ethanol to oleic acid molar ratio from 1/1 to 6/1, H2SO4 as the catalyst 1 and 5% wt of oleic acid, reaction time up to 180 min. The optimum conditions for the esterification reaction were molar ratio of ethanol/oleic acid 6/1, 5%wt H2SO4 relative to oleic acid, 70 °C, 90 min and conversion of oleic 0.92. The activation energy for the suggested model was 26625 J/mole for forward reaction and 42189 J/mole for equilibrium constant. The obtained results s

This research is carried out to study the effect of the external post-tensioning technique on the flexural capacity of simply supported composite castellated beam experimentally. In this research, seven composite castellated beams having the same dimensions and material properties were cast and tested up to failure by applied two concentrated loads at 700 mm from each end. Two external strands of 12.7 mm diameter were fixed at each side of the web of strengthening beams and located at depth 180 mm from top fiber of the section (dps) at each end of the beam. The strands have been tensioned by using a hydraulic jack with a constant stress of 100 MPa. This research aims to study the effect of the strengthening by different shapes of st

Abstract

     Travel Time estimation and reliability measurement is an important issues for improving operation efficiency and safety of traffic roads networks. The aim of this research is the estimation of total travel time and distribution analysis for three selected links in Palestine Arterial Street in Baghdad city. Buffer time index results in worse reliability conditions. Link (2) from Bab Al Mutham intersection to Al-Sakara intersection produced a buffer index of about 36%  and 26 % for Link (1) Al-Mawall intersection to Bab Al- Mutham intersection and finally for link (3) which presented a 24% buffer index. These illustrated that the reliability get worst for link

The study of human factors and the extent of their impact on the construction of land transport roads is of great importance because they are variable factors, which are on the contrary natural factors, and the impact of human factors on road construction operations is evident through the study of population distribution and size, and economic activities (agricultural, industrial, tourism). And its direct mutual relationship with the construction and extension of land transport routes and the development of each of them, and then directing them to serve urban and rural human settlements, which leads to their development and improvement of their economic, living and social conditions on the one hand, and contributes to the emergence

The solution to the problems and challenges of the twenty-first century requires the absorption of many transformations, such as demographic change, poverty reduction, the expansion of safe and clean energy without affecting the environment, as well as reducing health risks and other transitions. It also requires greater cooperation than is possible in the current global system, because both of these constraints and challenges, even if addressed locally or nationally, are because of the potential for their transnational impact, that is, their impact on the lives of people at the global level, Which is necessary to be fully addressed unless it is guided by a comprehensive global vision. This is what environmental governance provides in te

The absence of ecological perception in the local urbanization resulted in the lack of a clear conception of achieving sustainability in its simplest form in the urban reality and in the city of Baghdad in particular. The research assumes the possibility of achieving urban sustainability in Iraqi cities by applying the cities for the most effective methods to implemented ecological solutions and introducing appropriate urban planning tools and improve the living environment. The research focuses on the ability to define some aspects to achieve a sustainable local urban identity from global experiences. This was performed by proposing a scheduled theoretical framework, through which the features of sustainability can be extrapolated from the

The research aims to determine optimal urban planning and design indicators of the urban clusters form in hot arid zones through studying of three urban areas in Baghdad, analyzing their urban indicators which include floor area ratio (FAR), urban clusters height, building density or land coverage, green areas, paved areas, shading ratio and how they affect urban temperature. The research reached the conclusion that air outdoor temperature on urban areas affected primarily by shadows casted on the ground, the effect of shaded area equals (5) times the effect of paved areas and (3.7) times the effect of green areas, this means that increasing urban clusters height in hot arid zones could minimize air outdoor temperature, building