The fractional free volume (Fh) in polystyrene (PS) as a function of neutron -irradiation dose has been measured, using positron annihilation lifetime (PAL) method. The results show that Fh values decreased with increasing n-irradiation dose up to a total dose of 501.03× 10-2 Gy.
A percentage reduction of 2.14 in Fh values is noticed after the initial n-dose corresponding to a percentage reduction in the free volume equal to 42.14/Gy.
The total n-dose induces a percentage reduction of 7.26, corresponding to a percentage reduction of 1.45/Gy. These results indicate that cross -linking is the predominant process induced by n-irradiation.
The results suggest that n-irradiation induces structure changes in PS, causing cross-linking in PS chains, whereas the presence of oxygen during irradiation causes retardness of cross-linking yield, which consequently affects the values of the above mentioned parameter with respect to their values in case the irradiation is performed in vacuum
The research aims to identify the importance of using analytical procedures in the detection of creative accounting practices. To achieve this goal, (100) questionnaires were prepared and distributed to the auditors in the Federal Financial Supervision Bureau and the authorized auditors' offices and practitioners of the auditing profession in Iraq. For the purpose of testing the research hypothesis and analyzing data, some appropriate statistical methods have been used and the use of the statistical program (SPSS) to analyze the data. The results of the research showed that the analytical procedures and tests applied by the auditor have a role in revealing and limiting creative accounting practices and methods and that auditors u
... Show MoreThe majority of Iraqi translator-student have problems at two main levels: the conceptual level and the productive level. From different perspectives, such problems are either related to ‘language’ or to ‘cognition’. This binary view is an indication to the implicit and interchangeable relationship between language and cognition. The relationship between cognition language and translator starts with the first language and its effect on the Iraqi translators. Identifying the effect is the aim of the present study. It is hypothesized that Iraqi students are negatively influenced by the problems and weaknesses of first language schema. This reflects the major claim and later concludes that first language instruction in the Iraq
... Show MoreThe aim of this research is to diagnose the impact of competitive dimensions represented by quality, cost, time, flexibility on the efficiency of e-learning, The research adopted the descriptive analytical method by identifying the impact of these dimensions on the efficiency of e-learning, as well as the use of the statistical method for the purpose of eliciting results. The research concluded that there is an impact of the competitive dimensions on the efficiency of e-learning, as it has been proven that the special models for each of the research hypotheses are statistically significant and at a level of significance of 5%, and that each of these dimensions has a positive impact on the dependent variable, and the research recommended
... Show MoreIn this work, a ceramic model has obtained from Iraqi bentonite as a base material with limited additions of alumina and silica. The selected material can bear temperatures higher than the bearing temperature of bentonite as it achieved tolerance temperatures (1300°C) based on X-ray diffraction patterns. It was found that the addition of alumina and silica led to the occurrence of basic phases such as mullite, quartz, cordierite and feldspar in percentages that depended on the percentage of addition in the mixture and the firing temperature, which was (1000-1300)°C.
Abstract. Shatt Al-Arab River was the most important tide river in Iraq, it suffered from neglect and lack of maintenance in the past decades. The river embankment is constantly exposed to erosion processes due to several factors, one of the most important of these factors is the movement of water currents due to the tidal energy coming from the Arabian Gulf. In this study, one dimension unsteady-state model was implemented to study river flood capacity simulation by using HEC-RAS (5.0.7) software in Shatt Al Arab River and its tributaries. The data included flow rate, water level records were collected daily from 2018 to 2020 at different stations along the mentioned river and its feeders, additionally, the considered flood discharge data
... Show MoreThe species Vitex agnus-castus is an important medicinal plants and it is one of the cultivated and dicotyledon plants in Iraq. The anatomical of stem, petiole, midrib area, epidermis, veins, type of leaf stomata and seeds were studied by light microscope. In this research, shows the knowledge of anatomical characteristics of the studied plant, showing its importance as taxonomic characteristics through the sections of the stem, petiole, the midrib and the petals.
This study included the Zakhikhah area in the Al- Anbar desert, which it bounded on the north, east, and west by the Euphrates River and on the south by the Ramadi-Qaim road. Several exploratory field trips were taken to the study area. During this time, a semi-detailed area survey was carried out based on satellite imagery captured by American Land sat-7, topographic maps, and natural vegetation variance. All necessary field tools, including a digital camera and GPS device, were brought to determine the soil type and collect plant samples. All of these visits are planned to cover the entire state of Zakhikhah. All vegetation cover observations, identifying sampling sites and attempting to inventory and collect medicinal plants in t
... Show More
