In this study, the effect of ceramic coating on the performance and gases emission on diesel engine was investigated. A four-stroke, direct injected, single cylinder, diesel engine was tested at constant speed and at different load conditions without coating. Then, the inlet and exhaust valves faces were coated by about 500µm with ceramic materials. Ceramic layers were made of YttriaStabilized Zirconia (YSZ), and NiCrAl as a bond coat. The coating technique adapted in this work is the flame spray method. The engine with valves ceramiccoated research was tested for the same operation conditions of the engine (without coating). The results indicate a reduction in both fuel consumption by about 7.6% and particulate emissions by about (13% for HC and 14.5% for CO) with increasing in exhaust gases temperature after coating.
The research aims to identify the degree of the availability of knowledge, skill and ability as components of human capital, in addition to stand at the level of strategic agility upon tourism and travel agencies company of Jordan, the impact of human capital on strategic agility has been tested through distribution of a questionnaire on a Randomly Sample from Workers in Jordan tourist Companies of (349),a number of statistics techinces have been used simple liner Regrision and Multiplayer regession, it has shown that the degree of knowledge, ability and skill availability was high, and the same applies on strategic agility components, and shown out that there is a statistically significant impact between human capital and strate
... Show MoreOne of the most effective systems for managing water is subsurface trickle irrigation. Finding empirical formulas and studying the effect of soil texture are the main purposes of this paper. In order to reach an ideal irrigation system as a modern technique to save water, especially in arid regions, soil textures of loam, silt, and silt loam were studied on a subsurface trickle irrigation system by utilizing HYDRUS/2D. The trickle system is usually operated at low pressure, in this paper the used pressure is 30 cm with an emitter buried at 10, 15, and 20 cm at different diameters. Patterns of wetting fronts in both directions at various times depending on soil texture are gathered to
Spent catalysts for sulfuric acid production have large amount of vanadium and due to environmental authority it is required to reduce the vanadium contain of the spent catalyst. Experimental investigation was conducted to study the vanadium recovery from spent catalyst via leaching process using sodium hydroxide to study the effect of process variables (temperatures, sodium hydroxide molarities, leaching time and particle size) on vanadium recovery. The effect of process variables (temperature, particle size,molarities of sodium hydroxide and leaching time) on the percentages of vanadium recovery were investigated and discussed .It was found that the percentage of vanadium recovery increased with increasing temperature up to 100 , incre
... Show MoreGas lift is one of the most important artificial lift methods for increasing oil production, as wells often require this method after the reservoir's energy has decreased. In this research, an optimal gas lift system is designed for five horizontal wells in the Ahdab oil field, which suffers from low production. At the same time, water cut in some of these wells reaches 66%, while the productivity index is low in others, which makes the challenges clear, and a deep analysis is needed to find an optimal system. The Pipesim program is used to design the optimal gas lift system, which contains features that facilitate the implementation of the appropriate design and provide the ability to analyze and determine the optimal design v
... Show MoreMunicipalities.
Abstract
The purpose of this research is to measure the impact of regulatory flexibility dimensions (formal and authoritarian procedures) to achieve response to the requirements of high performance dimensions (the effective recruitment, intensive training, motivate employees, participation of workers) in the general municipal Directorate as one of the directorates of the Ministry of Municipalities and Public Works. For the purpose of this measure it has been selected sample composed of 88 individuals from the research community represents the levels of assistant general manager of department heads and managers of people and some of the staff to answer the questionnaire prepared for the purpose Hama
... Show MoreYY Lazim, NAB Azizan, 2nd International Conference on Innovation and Entrepreneurship, 2014
This paper is illustrates the sufficient conditions of the uniformly asymptotically stable and the bounded of the zero solution of fifth order nonlinear differential equation with a variable delay τ(t)
The research aims to identify the effect of using the strategy of Roundhouse on the achievement of fourth-grade students of computer and their Attitudes towards it. The research sample consisted of (61) fourth-grade secondary school students distributed into the experimental group consisted of (31) students study computer according to the Roundhouse strategy, and the control group consisted of (30) students follow the traditional method. The researcher designed an achievement test consisting of (30) items of multiple choice. To measure the attitudes of students towards the computer, a questionnaire of (32) paragraphs with three alternatives was designed by the researcher. The results showed that there is a statistically significant diffe
... Show MoreThe central nervous system is the most important system and is very sensitive to any accidental infection during ontogenesis; it includes brain and spinal cord. The cerebellum is the second largest part of the brain after cerebrum and it’s very sensitive to the abnormal changes during the embryological development. This study was designed to investigate the effect of the maternal exposure of selected concentrations of suspension of nanoparticles on the ontogenesis of the rat cerebellum after embryos implanted in uterus. A total of 60 female pregnant rats were divided in to three groups, each contains 20 females. Group1 (G1) was treated orally with 2mg/kg /body weight (b. wt) of suspension of silver nanoparticles (Ag NPs). While group 2 (G
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