The solidification process in a multi-tube latent heat energy system is affected by the natural convection and the arrangement of heat exchanger tubes, which changes the buoyancy effect as well. In the current work, the effect of the arrangement of the tubes in a multi-tube heat exchanger was examined during the solidification process with the focus on the natural convection effects inside the phase change material (PCM). The behavior of the system was numerically analyzed using liquid fraction and energy released, as well as temperature, velocity and streamline profiles for different studied cases. The arrangement of the tubes, considering seven pipes in the symmetrical condition, are assumed at different positions in the system, i

In Iraq, the risk of soil pollution by petroleum products increases with the growth of oil exploration, production and shipping large quantities of oil through pipelines over thousands of kilometers. Numerous oil spills have been documented recently in many sites due to damage in the oil industry infrastructures, which have led to soil contamination causing serious environmental hazards and deterioration to the soil and its engineering properties. So, it is essential to investigate the impact of oil leakage through the soil stratum consequently, assessing the eligibility of the contaminated soil for construction projects or identifying the appropriate treatment method. The paper investigates the general behaviour and the associated variatio

The annual performance of a hybrid system of a flat plate photovoltaic thermal system and a solar thermal collector (PVT/ST) is numerically analyzed from the energy, exergy, and environmental (CO2 reduction) viewpoints. This system can produce electricity and thermal power simultaneously, with higher thermal power and exergy compared to conventional photovoltaic thermal systems. For this purpose, a 3D transient numerical model is developed for investigating the system's performance in four main steps: (1) investigating the effects of the mass flow rate of the working fluid (20 to 50 kg/h) on the temperature behavior and thermodynamic performance of the system, (2) studying the impacts of using glass covers on the different parts of the s

In this study, nanoparticles were synthesized using the pulsed laser ablation technique, employing an Nd:YAG laser with a wavelength of 1064 nm. The ablation process was carried out at room temperature under varying laser energy of 950 mJ. The structural characteristics of the resulting nanoparticles were investigated using X-ray diffraction (XRD) and atomic force microscopy (AFM). The biological impact of the synthesized nanoparticles was assessed by administering two different doses (1 ml/kg and 4 ml/kg) to experimental animal models. The study evaluated changes in thyroid hormone levels, specifically thyroid-stimulating hormone (T_SH), triiodothyronine (T[Formula: see text] and thyroxine (T[Formula: see text]

Large – Almusseiyab soils survey project in mid Mesopotamian plain have
been chosen , because of its variation in soil series and reiteration map units, to
calculate the roundness of map units and roundness sorting values, in order to use
them as a pattern of map units shapes which help in interpret the distribution and
shapes of map units, which they were (18) soil series in (141) reiteration. Calculate
each map units roundness have been done and its value ranged between (0.09) to
(0.51), The average of roundness ranged between (0.250) for each MM1, MW5
soil series ,and (0.317) for DW45 . 99.30 % of samples were not good roundness
and with many sineuosity. The second group was a largest percentage 38.88 % with<

   The aim of the research is to use methods based on cost-based activities )ABC) to identify the activities that cause the costs resulting from the environmental impact of the gas filling company and then to manage on the basis of the activities to manage the costs of these activities, which in turn rationalizes the environmental costs by eliminating activities that do not add .The research a number of conclusions, the most important of which is that the management of the company should continuously seek to train and qualify its staff on the accounting systems, especially in the field of accounting of environmental costs, the high environmental costs by the company, bears as a result of its activity.

The study falls in Five chapters as follows:
Chapter One : definition of the Study including:
1. The problem of the study: the current study tries to answers two questions;
First: the effectiveness of the performance of the applicants in the department of Quran
Sciences and Islamic Education in the colleges of Education according the point of view of
their supervisors.
Second: what is the future vision for teacher training according to the assessment of the
performance of the applicant students?
2. The importance of the study: the application or the field training is of an important role
in the process of training the students for teaching; as it is considered the real scale of
success in the processes of ac