Polyimide/MWCNTs nanocomposites have been fabricated by solution mixing process. In the present study, we have investigated electrical conductivity and dielectric properties of PI/MWCNT nanocomposites in frequency range of 1 kHz to 100 kHz at different MWCNTs concentrations from 0 wt.% to 15 wt.%. It has been observed that the electrical conductivity and dielectric constants are enhanced significantly by several orders of magnitude up to 15 wt.% of MWCNTs content. The electrical conductivity increases as the frequency is increased, which can be attributed to high dislocation density near the interface. The rapid increase in the dielectric constant at a high MWCNTs content can be explained by the formation of a percolative path of the conducting network through the sample for a concentration corresponding to the percolation threshold. The high dielectric constant at a low frequency (1 kHz) is thought to originate from the space charge polarization mechanism. I-V characteristics of these devices indicate a significant increase in current with an increase in multi-walled carbon nanotube concentration in the composites. The SEM images show improved dispersion of MWCNTs in the PI matrix; this is due to the strong interfacial interactions.
The research aims to highlight the role played by the target costing technique as an administrative technique that is compatible with the rapid developments and changes in the external environment, with the information and scientific foundations it provides in the allocation of indirect costs and the accuracy in measuring the cost from the start of the project planning process up to the production process and indicating the extent of its impact on decisions Pricing in a way that contributes to the rationalization of pricing decisions in economic units in the light of intense competition and the multiplicity of alternatives.
The purpose of the research is to identify the role of Islamic banks in facing the financial crisis in Iraq for the period 2012-2014, and highlight the various factors that contributed to the emergence of the financial crisis, as well as to identify the problems and challenges facing the Islamic banking business in Iraq and identify the reasons and find appropriate solutions, And the development of treatments to avoid the occurrence of such problems and overcome them. The main findings of the research are as follows,Islamic banks (the sample of the study) were affected by the global financial crisis indirectly, as the financial crisis turned into an economic crisis affecting the real economy, because the activity of Islamic banks is more
... Show MoreThis paper deals with two preys and stage-structured predator model with anti-predator behavior. Sufficient conditions that ensure the appearance of local and Hopf bifurcation of the system have been achieved, and it’s observed that near the free predator, the free second prey and the free first prey equilibrium points there are transcritical or pitchfork and no saddle node. While near the coexistence equilibrium point there is transcritical, pitchfork and saddle node bifurcation. For the Hopf bifurcation near the coexistence equilibrium point have been studied. Further, numerical analysis has been used to validate the main results.
Braces in straight bridge systems improve the lateral-torsional buckling resistance of the girders by reducing the unbraced length, while in horizontally curved and skew bridges, the braces are primary structural elements for controlling deformations by engaging adjacent girders to act as a system to resist the potentially large forces and torques caused by the curved or skewed geometry of the bridge. The cross-frames are usually designed as torsional braces, which increase the overall strength and stiffness of the individual girders by creating a girder system that translates and rotates as a unit along the bracing lines. However, when they transmit the truck’s live load forces, they can produce fatigue cracks at their connection
... Show MoreNanotechnology is a continually expanding field for its uses and applications in multiple areas i.e. medicine, science, and engineering. Biosynthesis is straightforward, less-toxicity, and cost-effective technology. TiO2 NPs biosynthesis has attained consideration in recent decades. In this study, probiotic bacteria were isolated from cow’s raw milk samples, and then were identified by using the Vitek2 system; as Leuconostoc spp. included Leuconostoc mesenteroides subsp. mesenteroides (Leu.1), Leuconostoc mesenteroides subsp. cremoris (Leu.4), and Leuconostoc pseudomesenteroides (Leu.14). All Leuconostoc spp. isolates showed an ability for TiO2 NPs bio-production, after being incubated at anaerobic conditions (30 o C/ 24 h) in DeM
... Show MoreDeveloping smart city planning requires integrating various techniques, including geospatial techniques, building information models (BIM), information and communication technology (ICT), and artificial intelligence, for instance, three-dimensional (3D) building models, in enabling smart city applications. This study aims to comprehensively analyze the role and significance of geospatial techniques in smart city planning and implementation. The literature review encompasses (74) studies from diverse databases, examining relevant solutions and prototypes related to smart city planning. The focus highlights the requirements and preparation of geospatial techniques to support the transition to a smart city. The paper explores various aspects,
... Show MoreObjective: The study aims to evaluate nurses' knowledge toward care of unconscious adult patients and identify the relationship between nurses’ knowledge toward care of unconscious adult patient and their demographic characteristics of age, gender, Marital Status, level of qualification and years of experience. Methodology: A descriptive study (quantitative design) was carried out by using quasi experimental design to study nurses' knowledge, attitudes and practices toward care of unconscious adult patients at teaching hospitals in Al-Hilla City from September 2018 up to June 2019. A purposively sample has been chosen in which included 60 nurses who work in ICUs within two hospitals (Imam Al-Sadiq teaching hospital and Al-Hilla general
... Show MoreListening comprehension of Iraqi EFL college students are not given time for practice, and incorporate in the programme of the Department of English, therefore, students are not well-prepared to comprehend the spoken language also the Iraqi EFL College students are deficient in comprehending the spoken English. So, listening strategies require a larger amount of consistent practice. The present study aims at finding out the effect of teaching the proposed listening strategies programme on EFL university students' listening comprehension. The sample consists of 104 of 1st year college students at the Department of English Language, College of Education Ibn-Rushed for Humanities. The programme deals with the following strategies: summrazing-n
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