The aim of this research is to uncover the science processes included in the teacher’s guide to scientific experiments for science books for grades (first-second) for the intermediate stage, The research sample included all the scientific experiments contained in the teacher’s guide for scientific experiments for the intermediate stage, The researcher used the descriptive and analytical method, and designed an analysis tool, The content of science operations, and verified its validity and consistency, and after using percentages and ranks for statistical treatment, the research reached the following results: The number of practical experiments varies from one class to another in the intermediate stage, where the highest percentage appears in the teacher's guide for scientific experiments for the second grade, with (60) experiments and (57%), and the lowest is the teacher's guide for scientific experiments for the first grade by (46) experiments and by (43%) The most frequent basic science process is the observation process, while the most integrative science process is the experimentation process, and the scientific experiments did not deal with the processes of prediction and control of variables.
This research dealt with choosing the best satellite parking orbit and then the transition of the satellite from the low Earth orbit to the geosynchronous orbit (GEO). The aim of this research is to achieve this transition with the highest possible efficiency (lowest possible energy, time, and fuel consumption with highest accuracy) in the case of two different inclination orbits. This requires choosing a suitable primary parking orbit. All of the methods discussed in previous studies are based on two orbits at the same plane, mostly applying the circular orbit as an initial orbit. This transition required the use of the advanced technique of the Hohmann transfer method for the elliptical orbits, as we did in an earlier research, namely
... Show MoreA polycrystalline CdTe film has been prepared by thermal evaporation technique on glass substrate at substrate temperature 423 K with 1.0 m thicknesses. The film was heated at various annealing temperature under vacuum (Ta =473, 523 and K). Some of physical properties of prepared films such as structural and optical properties were investigated. The patterns of X-ray diffraction analysis showed that the structure of CdTe powder and all films were polycrystalline and consist of a mixture of cubic and hexagonal phases and preferred orientation at (111) direction.
The optical measurements showed that un annealed and annealed CdTe films had direct energy gap (Eg). The Eg increased with increasing Ta. The refractive index and the real p
This research presents a study of using an additive for the objective of increasing the setting time of a material used in several aspects in the constructional field, this material is “Local-Gypsum” which is locally called “Joss”, and the additive used in this study is “Trees Glue Powder” denoted by “TGP”. Nine mixtures of Local-gypsum (joss) had been experimented in the current study to find their setting time, these mixes were divided into three groups according to their water-joss ratios (W/J) (0.3, 0.4 and 0.5), and each group was sub-divided into three sub-groups according to their TGP contents (0.0%, 0.3% and 0.6%). It was found that, when TGP is added with the
Because of Cadmium selenide quantum dots (CdSe quantum dots) has a tuning energy gap in the visible light range, therefore; it is provided a simple theoretical model for the absorption coefficient of CdSe quantum dots, where the absorption coefficient determines the extent to which the light of a material can penetrate a specific wavelength before it is absorbed. CdSe quantum dots have an energy gap can be controlled through two effects: the temperature and the dot size of them. It is found that; there is an absorption threshold for each directed wavelength, where CdSe quantum dots begin to absorb the visible spectrum at a size of 1.4 nm at room temperature for a directed wavelength 3
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
... Show MoreThe research aims to analyze and evaluate the urban land use according to the needs of the current and future population by adopting the planning criteria for the holy city of Karbala. In the theoretical side, we discussed the most important concepts of urban land use planning. In the practical aspect of the study, field surveys were conducted to obtain the required information. Using the GIS program, the land uses were planned and executed, Analysis By comparing the per capita use of urban land with criteria and the production of maps.
The main findings of the study are that there is a large deficit in meeting some of the needs of the urban land uses and the basic services of the city. The research recommended that the needs of
... Show MoreEducation is a process of learning and education at the same time. As the conditions of modern life necessitate every person to keep learning, education has become a necessity to meet life needs. The society today is concerned with the educational process and aims to live up the expectations. Since education is an integral part of education and its means, it has become as a mean to achieve its purposes. The educational environment was a traditional environment limited to specific inputs, possibilities and stimulus of both teacher and student. Due to the latest advancement, the educational environment has been expanded to become a rich, with strong connections. It has expanded to encompass the entire global environment. The current
... Show MoreIn this paper, a harvested prey-predator model involving infectious disease in prey is considered. The existence, uniqueness and boundedness of the solution are discussed. The stability analysis of all possible equilibrium points are carried out. The persistence conditions of the system are established. The behavior of the system is simulated and bifurcation diagrams are obtained for different parameters. The results show that the existence of disease and harvesting can give rise to multiple attractors, including chaos, with variations in critical parameters.
The formation of the identity of the ego associates with adolescence and the beginnings of youth, where represents the basic requirement for growth. This stage reflects a turning point towards the necessary autonomy for the growth of normal in adulthood that needs the ego growth from his point of view to pass eight consecutive stages of the individual faces in each particular crisis. It is determined by its growth path depending on the nature of solved positively or negatively, influenced by several factors: biological, social, cultural, personal, and a dogmatic obstacle to personal thinking which refers to the kind of sclerotic thought a bigot to the inside of obsolete beliefs refuse to discuss and consider. The final idea is debatable
... Show MoreSelf- curing is the potential of lightweight aggregate to absorption great amount of water thru mixing which prominently can moves to the paste during hydration process. Self- curing empowers a water to be distributes more evenly act out the cross section. Whereas, the external curing water is only able to penetrate several millimetres into concrete with low water cement ratio. Brick dust accumulates in the demolish site creates serious environmental contamination. This study investigates the effect of brick dust recovered from construction site on the Properties of mortar cured in three curing conditions. Mortar in this study produced using BD as cement additive with (2, 4, 6, and 8) % by weight of cement. BD was used a
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