Objectives This work presents laser coating of grade 1 pure titanium (Ti) dental implant surface with sintered biological apatite beta-tricalcium phosphate (β-TCP), which has a chemical composition close to bone. Materials and methods Pulsed Nd:YAG laser of single pulse capability up to 70 J/10 ms and pulse peak power of 8 kW was used to implement the task. Laser pulse peak power, pulse duration, repetition rate and scanning speed were modulated to achieve the most homogenous, cohesive and highly adherent coat layer. Scanning electron microscopy (SEM), energy dispersive X-ray microscopy (EDX), optical microscopy and nanoindentation analyses were conducted to characterise and evaluate the microstructure, phases, modulus of elasticity of the coating layer and calcium-to-phosphate ratio and composition. Results showed that the laser power and scanning speed influenced coating adherence. The cross-sectional field-emission scanning electron microscopy images at low power and high speed showed poor adherence and improved as the laser power increased to 2 kW. Decreasing the scanning speed to 0.2 mm/s at the same power of 2 kW increased adherence. EDX results of the substrate demonstrated that the chemical composition of the coat layer did not change after processing. Moreover, the maps revealed proper distribution of Ca and P with some agglomeration on the surface. The sharp peaks on the X-ray diffraction patterns indicated that β-TCPs in the coat layer were mostly crystalline. The elastic modulus was low at the surface and increased gradually with depth to reach 19 GPa at 200 nm; this value was close to that of bone. The microhardness of the coated substrate increased by about 88%. The laser pulse energy of 8.3 J, pulse peak power of 2 kW, pulse duration of 4.3 min, repetition rate of 10 Hz and scanning speed of 0.2 ms−1 yielded the best results. Conclusion: Both processing and coating have potential use for dental implant applications.
The natural ventilation in buildings is one of effective strategies for achieving energy efficiency in buildings by employing methods and ways of passive design, as well as its efficiency in providing high ranges of thermal comfort for occupants in buildings and raises their productivity. Because the concept of natural ventilation for many people confined to achieve through the windows and openings only, become necessary to provide this research to demonstrate the various passive design strategies for natural ventilation. Then, research problem: Insufficient knowledge about the importance and mechanism of the application of passive design strategies for natural ventilation in buildings. The research objective is: Analysis of passive desi
... Show MoreOptical burst switching (OBS) network is a new generation optical communication technology. In an OBS network, an edge node first sends a control packet, called burst header packet (BHP) which reserves the necessary resources for the upcoming data burst (DB). Once the reservation is complete, the DB starts travelling to its destination through the reserved path. A notable attack on OBS network is BHP flooding attack where an edge node sends BHPs to reserve resources, but never actually sends the associated DB. As a result the reserved resources are wasted and when this happen in sufficiently large scale, a denial of service (DoS) may take place. In this study, we propose a semi-supervised machine learning approach using k-means algorithm
... Show MoreThis study aim to identify the concept of web based information systems since its one of the important topics that is usually omitted by our organizations, in addition to, designing a web based information system in order to manage the customers data of Al- Rasheed bank, as a unified information system that is specialized to the banking deals of the customers with the bank, and providing a suggested model to apply the virtual private network as a tool that is to protect the transmitted data through the web based information system.
This study is considered important because it deals with one of the vital topics nowadays, namely: how to make it possible to use a distributed informat
... Show MoreBackground: Many countries recommend the use of long-acting reversible contraceptive intrauterine device immediately after cesarean delivery. The cesarean delivery rate in Iraqi public hospitals is 32.2% and may reach 85.8% in private hospitals. Immediate post-partum intrauterine device insertion at cesarean is rarely done in Iraq.
Objectives: To assess the safety and practicality of immediate post-partum intrauterine device insertion during cesarean delivery for family planning and pregnancy spacing in Iraqi women.
Subjects and Methods: A single arm clinical trial included 150 eligible women who attended Al-Elwiyah Maternity Teaching Hospital or Al Hayat Rahibat Hospita
... Show MoreIn this study, a novel application of lab-scale dual chambered air-cathode microbial fuel cell (MFC) has been developed for simultaneous bio-treatment of real pharmaceutical wastewater and renewable electricity generation. The microbial fuel cell (MFC) was provided with zeolite-packed anodic compartment and a cation exchange membrane (CEM) to separate the anode and cathode. The performance of the proposed MFC was evaluated in terms of COD removal and power generation based on the activity of the bacterial consortium in the biofilm mobilized on zeolite bearer. The MFC was fueled with real pharmaceutical wastewater having an initial COD concentration equal to 800 mg/L and inoculated with anaerobic aged sludge. Results demo
... Show MoreBackground: It is well-known that silicon oil (SO) injection into the vitreous cavity after pars plana vitrectomy is usually associated with high intraocular pressure.
Objectives: To determine the influence of silicon oil (SO) removal on IOP level after pars plana vitrectomy for spontaneous rhegmatogenous retinal detachment (RRD)
Subjects and Methods: A prospective study was conducted at Ibn Al-Haitham eye teaching hospital, Baghdad- Iraq. Intraocular pressure (IOP) was measured pre and post SO removal in patients who have underwent retinal detachment surgery with SO injection of 1000 centistokes (cSt) viscosity. Baseline IOP was measured for all the patient before the SO
... Show MoreThe research aims to identify the impact of using the electronic participatory learning strategy according to internet programs in learning some basic basketball skills for middle first graders according to the curricular course, and the sample of research was selected in the deliberate way of students The first stage of intermediate school.As for the problem of research, the researchers said that there is a weakness in the levels of school students in terms of teaching basketball skills, which prompted the researchers to create appropriate solutions by using a participatory learning strategy.The researchers imposed statistically significant differences between pre and post-test tests, in favor of the post tests individually and in favor of
... Show MoreOne of the most common procedures in oral surgery is the removal of impacted mandibular third molars, often followed by pain, swelling, alveolitis, and trismus. Purpose. To compare the outcomes of the intrasocket application of 1% hyaluronic acid oral gel (HA) and advanced platelet-rich fibrin (A-PRF) on the expected postoperative complications, pain, swelling, and trismus follow the surgical extraction of the impacted mandibular third molar. Material and Methods. A randomized controlled trial was conducted at the Oral and Maxillofacial Surgery Unit, Dental Teaching Hospital. Healthy patients who required surgical removal of the impacted mandibular third molar were divided randomly into three groups. The extraction site of the group
... Show MoreThe audit profession today gets an increasing interest by the financial , economic and legal contemporary societies , because of the importance of the technical & neutral auditor’s opinion to the financial reports beneficiaries in order to enable them making their investment decisions , but some of them whom suffered damage or loss when they made that decisions according to the mentioned financial statements which consolidated with auditor’s report , exposed the function to a responsibility and credibility crisis in addition to missing the trust especially at the latest years. They always ask why or what is the reason that cause the auditor didn’t giving us any warning signs about the economic mater for that companies.
Forward-swept wings were researched and introduced to improve maneuverability, control, and fuel efficiency while reducing drag and they are often used alongside canards, to further enhance their characteristics. In this research, the effects of canard dihedral angles on the wing loading of a forward-swept wing in transonic flow conditions were studied, as the wing loading provides a measure of wing’s efficiency (lift/drag). A generic aircraft model from literatures was selected, simulated, and compared to, using CFD software ANSYS/Fluent where the flow equations were solved to calculate the aerodynamic characteristics. The research was carried at two different Mach numbers, 0.6 and 0.9, for five different canard dihedral angles which tra
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