This contribution provides an atomistic understanding into the impact of W, Nb, and Mo co-substitution at Hf-site of cubic HfO2 lattice to produce Hf1−xTMxO2 system at x = 25%. The calculations have been performed under the framework of density functional theory supported by Habbured parameter (DFT+U). Structural analysis demonstrates that the recorded lattice constants is in good coherence with the previously published results. For the lattice parameters, contraction by 1.33% comparing with the host system has been reported. Furthermore, the doping effect of TM on the band gap leads to its reduction in the resulting Hf0.75TM0.25O2 configurations. The partial density of states (PDOS) indicate that hybridization through localized electronic energy states from TM-5 and 6 d orbitals and O-2 p orbital have participated in narrowing the band gap. Population analysis displays that Hf0.75TM0.25O2 compounds revealed ionic and covalent behavior for Hf-O and TM-O bonds, respectively. The optical investigation portrays that Hf0.75TM0.25O2 systems would absorb a broad range of ultra violet (UV) electromagnetic waves which hence consider them as suitable candidates in optoelectronic memristors industries. Optical analysis also revealed a rise in the optical conductivity and absorption in higher photon energy extent. These compounds are suitable for photovoltaic and other optoelectronic applications. The zero values of the optical conductivity for the simulated systems in a broad range of electromagnetic waves confirm the impossibility of the electronic charge transfer to be occurred through the systems and hence preventing the leakage current which is not preferred in optoelectronic devices such as metal oxide semiconductor field effect transistors (MOSFETs).
In this paper, the effect of wear in the fluid film journal bearings on the dynamic behavior of rotor bearing system has been studied depending on the analytical driven of dynamic stiffness and damping coefficients of worn journal bearing. The finite element method was used to modeling rotor bearing system. The unbalance response, critical speed and natural frequency of rotor bearing system have been studied to determine the changes in these parameters due to wear. MATLAB software was used to find the analytical values of dynamic coefficients of journal bearing. The results of rotor mounted on fluid film journal bearings showed that the wear in journal bearing increases the amplitude of unbalance response and decrease critical speed, sta
... Show MoreThe adoption of the concept of preventive war in any country especially in a country like the United States result in a lot of serious consequences, so that pre-emptive military action may alter certain regional arrangements based on the basis of political and security balance, and reduce the incidence of tensions that may worsen a sudden during the application of preventive war, so the concept is applicable to be a risk much more when you face the reality and that because the issues more importantly, it should prepare a detailed and careful study of the post –stage of the use of preventive military action and this requires realy no papers insist or documents discuss this but accurate this field study of the situation thereafter.
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KE Sharquie, SA Al-Meshhadani, AA Al-Nuaimy, Saudi medical journal, 2007 - Cited by 9
The concept of meaning is one of the most important topics that have occupied the mind of the recipient and critic in all the arts, especially the plastic arts, where we find that the art of contemporary plastic art, in particular sculpture has multiple readings and many critics differed in terms of different reading and views of the same artistic achievement.
This research will identify the different works of contemporary Iraqi sculptors while presenting and studying their works, as well as (studying the problem of meaning) of the artistic achievements of the sculptors in particular. The various parties interested in Iraqi sculpture did not seize the problem of the objective and subjective meaning of contemporary Iraqi sculpture
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In the last decades, using mineral admixture in concrete became very necessary to improve concrete properties and reduce CO2 emissions associated with the cement production process. Subsequently, more sustainable concrete can be obtained. Ternary blended cement containing two different types of mineral admixture can achieve ambitious steps in this trend. In this research, the synergic effects of mineral admixtures in ternary blended cement and its effects on concrete fresh properties, strength, durability, and efficiency factors of mineral admixture in ternary blended cement, were reviewed. The main conclusion reached after reviewing many literature pieces is that the concrete with ternary blended cement
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Risk identification and assessment can be analysed using many risk management tools. Fishbone diagram is one of these techniques which can be employed, for the identification of the causes behind the construction failure, which has become a phenomenon that often gets repeated in several projects. If these failures are not understood and handled scientifically, it may lead to disputes between the project parties. Additionally, the construction failure also leads to an increase in the project budget, which in turn causes a delay in the completion of the projects. Punching shear in reinforcement slab may be one of the reasons for construction failures. However, there are many doubts about other causes that lead to this failure as w
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This research aims to study the economic, social, and political reality of Iraqi women by identifying the obstacles and diagnosing their empowerment trends in various fields, assessing the extent of their participation in economic activity, and re-achieving balance between women and men by reducing the gender gap between them and reducing the percentage of female unemployment to the lowest possible level. Is achieved by enhancing confidence in Iraqi women by enacting laws and making decisions that allow them to access resources freely. The researcher used the descriptive and analytical method to deal with information and data related to the research topic over a specific period (1990-2018), using local, Arab, and international re
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The statistical distributions study aimed to obtain on best descriptions of variable sets phenomena, which each of them got one behavior of that distributions . The estimation operations study for that distributions considered of important things which could n't canceled in variable behavior study, as result this research came as trial for reaching to best method for information distribution estimation which is generalized linear failure rate distribution, throughout studying the theoretical sides by depending on statistical posteriori methods like greatest ability, minimum squares method and Mixing method (suggested method).
The research
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