Preferred Language
Articles
/
jbcd-3090
Natural preparation of rice husk-derived silica and eggshell-derived calcium carbonate composite as a coating material for dental implant
...Show More Authors

Background: The world is in front of two emerging problems being scarceness of virgin re-sources for bioactive materials and the gathering of waste production. Employment of the surplus waste in the mainstream production can resolve these problems. The current study aimed to prepare and characterize a natural composite CaO-SiO2 based bioactive material derived from naturally sustained raw materials. Then deposit this innovative novel bioactive coating composite materials overlying Yttria-stabilized tetragonal zirconia substrate. Mate-rials and method; Hen eggshell-derived calcium carbonate and rice husk-derived silica were extracted from natural resources to prepare the composite coating material. The manufac-tured powder was characterized via Fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FESEM), X-ray fluorescence (XRF), X-ray diffraction (XRD) and particle size analyzer. The bioactive composite was deposited through radiofre-quency (Rf) reactive magnetron sputtering overlying disc-shaped samples with a dimension of 10 mm diameter were prepared from partially sintered Yttria-stabilized tetragonal zirconia polycrystal (Y-TZP). Results: The particle size of the rice husk-derived ranged between (480.4 – 606.1) nm with a mean particle diameter of 541 nm. The eggshell derived calcium carbonate powder presented a particle size between (266.4-336) nm and a mean particle diameter of 299.9 nm. The XRD data revealed the crystalline nature and phase composition of the natural prepared calcium carbonate powder and demonstrate the monocrystalline nature of natural SiO2. FTIR spectrometer showed the emergence of novel spectra separated from the two innovative components. XRF analysis revealed that 99.4% of the rice husk is SiO2 while eggshell-derived powder is mainly composed of calcium oxide. Fe-SEM images of the coated zirconia exhibited average thickness of the natural CaCO3/SiO2 coat layer may reach to12.84 µ. Conclusion: The prepared composite derived from natural resource waste is suitable to be utilized as a coating material for ceramic dental implants with promising biological and mechanical properties.

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Jul 07 2013
Journal Name
Journal Of Educational And Psychological Researches
knowledge management and managers have a primary school principals from the standpoint of their assistants
...Show More Authors

knowledge management and managers have a primary school principals from the standpoint of their assistants M . Dr. Suad Vegetables Abbas Research problem: The administration school require a leader administratively The efficiency and skills of management and knowledge to make it effective in the administration follows the scientific method and knowledge of those who through administrative methods emanating from the trends of modern management in the management of educational , as well as the presence of the leaders of effective management has the knowledge and know-how administrative work and how to deal with others and investment optimized for all of the resources available through the future capable of Orientalism to the extent that ou

... Show More
View Publication Preview PDF
Publication Date
Sun Dec 31 2000
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Adsorption of NO2/N2O4 into Water and Dilute Nitric Acid in a Double Stirrer Adsorber
...Show More Authors

View Publication Preview PDF
Publication Date
Mon Dec 16 2024
Journal Name
Light & Engineering
The Design and Experimental Realization of a Laser-Based Heating System Using Recycled Laser Module
...Show More Authors

Laser is a powerful device that has a wide range of applications in fields ranging from materials science and manufacturing to medicine and fibre optic communications. One remarkable

View Publication
Publication Date
Wed Nov 30 2022
Journal Name
مجلة الجامعة العراقية
The competencies of lecturers and their roles in managing E-training workshops, a Pedagogical Pointview
...Show More Authors

The aim of the research is to shed light on identifying the extent of the university professor's competencies and their roles in managing and training participants in e-training workshops as a pedagogical point view. The research sample consisted of a group of (30) university professors (lecturers) in the training workshops, in scientific,humanitarian and social disciplines, including (12) a university professor (holding a trainer certificate), , the research methodology is descriptive, and the community is a group of trained participants. (115) participated in (40) e-training workshops organized by the Center for Continuing Education at the University of Baghdad (and the selection of workshops within the researcher's specialization in the

... Show More
View Publication
Publication Date
Fri Dec 01 2017
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Tax Exemptions and their impact in reducing the phenomenon of tax evasion: A field study
...Show More Authors

The research aims to verifying the tax exemptions granted in accordance with the Iraqi tax legislations, showing their suitability for basic tax rules, and identifying their role to reduce the tax evasion phenomenon and the negative effects resulting therefrom, which arerepresented by a decrease in the proceeds of tax revenue and therefore leadings to a reduction of public revenues of the state. Also, the research tries to identify the ways to reduce cases of tax evasion due to their reflection positively on the public budgetof the state. The data of the research was collected through two models of questionnaires distributed to a sample of taxpayers from some professions and a sample of the tax administration staff. The research has reac

... Show More
View Publication
Crossref
Publication Date
Wed Jun 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Competitiveness of an enterprise under a flexible manufacturing system. Manufacturing strategy and flexibility - Case study
...Show More Authors

The research has designed for studying the relationship between manufacturing strategy and its flexibility under the flexible manufacturing system with their reflection on the competitive environmental performance of the firm. To interpret and tackle the problem, a hypothesis has formulated stating that “ the competitive performance of a firm is interpreted by the manufacturing strategy and flexibility which are derived from the firm and its business  strategies under the flexible manufacturing system”. Related literatures with their theoretical dissertations, which enhanced the thoughtful content, have analyzed. An illustrative case study on the flexible manufacturing system at Toyota Motors Corporation working at the g

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Aug 01 2011
Journal Name
Journal Of Engineering
EXHAUST ANALYSIS AND PERFORMANCE OF A SINGLE CYLINDER DIESEL ENGINE RUN ON DUAL FUELS MODE
...Show More Authors

Generally fossil based fuels are used in internal combustion engines as an energy source.
Excessive use of fossil based fuels diminishes present reserves and increases the air pollution in
urban areas. This enhances the importance of the effective use of present reserves and/or to develop
new alternative fuels, which are environment friendly. Use of alternative fuel is a way of emission
control. The term “Alternative Gaseous Fuels” relates to a wide range of fuels that are in the
gaseous state at ambient conditions, whether when used on their own or as components of mixtures
with other fuels.
In this study, a single cylinder diesel engine was modified to use LPG in dual fuel mode to study
the performance, emis

... Show More
View Publication Preview PDF
Crossref (9)
Crossref
Publication Date
Thu Jul 31 2025
Journal Name
مجلة واسط للعلوم الانسانية
Artificial Intelligence in English Language Education in Iraq: A Review study of Interventions and Perceptions
...Show More Authors

AI in teaching English is reshaping language learning. While interest in AI-supported education is growing worldwide, research in this area is still emerging in Iraq. This review synthesizes empirical AI-based intervention studies to enhance English language learning in Iraqi higher education, and the perceptions of stakeholders regarding AI tools in language instruction. The reviewed intervention studies, comprising studies employed different AI platforms to support grammar instruction, speaking fluency, writing feedback, and pragmatic competence. These interventions yielded improvements in learners’ performance, motivation, and communicative confidence. In parallel, perception-focused studies revealed positive attitudes toward A

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Oct 01 2022
Journal Name
The Egyptian Journal Of Hospital Medicine
Study on Viral Infection and Related Parameters in A Sample of Diabetes Mellitus Type 2
...Show More Authors

View Publication
Scopus (2)
Scopus Crossref
Publication Date
Sun Jan 01 2012
Journal Name
Journal Of Engineering
DESIGN OF A VARIABLE GAIN NONLINEAR FUZZY CONTROLLER AND PERFORMANCE ENHANCEMENT DUE TO GAIN VARIATION
...Show More Authors

In this paper, variable gain nonlinear PD and PI fuzzy logic controllers are designed and the effect of the variable gain characteristic of these controllers is analyzed to show its contribution in enhancing the performance of the closed loop system over a conventional linear PID controller. Simulation results and time domain performance characteristics show how these fuzzy controllers outperform the conventional PID controller when used to control a nonlinear plant and a plant that has time delay.