Aim: surface modification of titanium using fiber laser 1064 nm to enhance the bond strength to resin cement. Material and Methods: thirty titanium discs of 0.6 cm x 0.3 cm (diameter and thickness respectively) were categorized after preparation into three groups (n=10) as follows: control group with no surface treatment and two test groups were treated with fiber laser after estimation the appropriate parameters in the pilot study which are 81 ns pulse duration, 30,000 Hz frequency, 50 µm spot size and 10,000 mm/s scanning speed and different average power values (10 W and 20 W) depending on the tested group. Titanium discs surface characterization was performed by scanning electron microscope (SEM), a
... Show MoreThis Action research aimed at Assisting Students of Faculty of Educational Sciences at Al-Quds Open University to design computerized lessons using the Power Point software and according to ADDIE model. The study sample consisted of 40 students who were taking a course titled Technology of Education during the second semester of the 2014-2015 academic year and three academic instructors . To collect the required date , the researchers used focus group technique and structured interviews to get information from the 40 students and the three academic instructors involved in the course Technology of Education in QOU /Nablus Branch. In addition to these methods, a workshop with a guiding checklist was employed t
... Show MoreThis study was conducted to evaluate the effects of black tea on Pseudomonas
aeruginosa isolated from eye infection. One hundred samples (corneal scrapings)
were obtained. Approximately, 77% of the cases were due to contact lens wear
followed by 15 % trauma and 8% with unknown history. The isolates identified as
P. aeruginosa were 30% (23/77 CL) and 25% (2/8 Unknown). On the other hand,
the Kirby-Bauer antibiotic sensitivity assay showed that 100% of the isolates were
sensitive to Neomycin, Gentamicin and Amikacin. While 91.6% were sensitive to
Carbenicillin and Ceftriaxone; 66.6% were sensitive to Cefotaxime and 0% were
sensitive to Tertacycline. Only two isolates were found to be multidrug resistant.
Screenin
Sulfamethoxazole (SMX) was added to P-N,N-dimethyl amino benzaldehyde (PDAB) by condensation reaction in acidic medium to form, a yellow colored dye compound which exhibits maximum absorption (λmax) at 450.5 nm. The concentration of (SMX) was determined spectrophotometrically. The optimum reaction conditions and other analytical parameters were evaluated. In addition to classical univariate optimization, design of experiment method has been applied in optimization of the variables affecting the color producing reaction. Beer’s law obeyed in the concentration range of 0.1-10 μg.mL-1 with molar absorptivity of 5.7950×104 L.mol-1.cm-1. The limit of detection and Sandell's sensitivity value were 0.078 μ
... Show MoreCitrate-gel auto combustion technique was used to synthesize nickel-copper mixed ferrite nanoparticles NixCu1-xFe2O4 (x= 0.0, 0.4, 1.0) with different calcinating temperatures (200, 450, 650 and 850 °C). Structural, morphological, magnetic, and electrical properties were studied using X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), and LCR meter in order to determine significant influences of Cu2+ cations content in nickel ferrite. The XRD patterns showed that all compositions had cubic spinels, except CuFe2O4
... Show MoreThe present paper deals with experimental investigation of the performance of air cooled split air conditioner, with evaporative water mist pre cooling to increase the cooling capacity and reduce the consumption power under hot and dry climate. This investigation considers how the performance can be enhanced by using water mist to pre-cool ambient air entering the condensers by adiabatic cooling process which depends on the ambient air wet bulb temperature; as well the condensing temperature and condensing pressure will be decreased accordingly. So the cooling capacity would be increased and consumption power would be decreased, consequently the energy ratio, EER would be improved. The performance of air cooled air conditioner with water
... Show MoreA novel series of pyrazole derivatives containing imidazo[1,2-a]pyridine D1-D8 moiety has been synthesized. The reaction of 2-aminopyridine with 4-phenylphenacyl bromide and 4-bromophenacyl bromide gave the products A and A1, respectively. These products then reacted with DMF and POCl3 to obtain new aldehyde derivatives B and B1. These two aldehydes were condensed with various acetophenone substitutes to yield the corresponding chalcone derivatives C1-C10. Following this, the cycloaddition reaction with hydrazine hydrate provided new pyrazole derivatives D1-D8. The prepared compounds
... Show More<span lang="EN-US">Proper employment of Hybrid Wind/ PV system is often implemented near the load, and it is linked with the grid to study dynamic stability analysis. Generally, instability is because of sudden load demand variant and variant in renewable sources generation. As well as, weather variation creates several factors that affect the operation of the integrated hybrid system. So this paper introduces output result of a PV /wind via power electronic technique; DC chopper; that is linked to Iraqi power system to promote the facilitating achievement of Wind/ PV voltage. Moreover, PSS/E is used to study dynamic power stability for hybrid system which is attached to an effective region of Iraqi Network. The hybrid system
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