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), and surface roughness tester. Following these tests, resin cement application to titanium discs was performed. Shear bond strength (SBS) values were determined by universal testing machine. ANOVA and Tukey HSD tests were used for analyzing of data (α = 0.05).Results: Higher average surface roughness (Ra) value was observed in (10 W) group followed by (20 W) group and the lowest surface roughness value was in the control group, additionally lowest SBS value was obtained from the control group and the highest SBS value was obtained from (20 W) group followed by (10 W) group. Conclusion: bond strength between titanium and resin cement can be significantly enhanced by using fiber laser as a surface treatment. Average power of fiber laser is essential parameter in enhancing the roughness of titanium surface and bonding to resin cement.
A high power N2 laser of the three stage-Blumlein circuit designed, which consist two identical electrodes, four capacitors and three spark gaps which designed discharge geometry with minimum inductance. This system gives a maximum energy 18 mJ with a pulse time 6.65 ns and wave length 337.1 nm. The distance between spark gap terminals has large effect on the output energy. The ideal distance were 11 mm between the terminals for the first spark gap and 4 mm between the terminals for the second spark gap, the distance between the terminals of the spark gaps has a significant effect on the resulting energy, where the energy decreases when the distance between the terminals of the first and second s
... Show MoreOne of the most important problems that faces the concrete industry in Iraq is the deterioration due to internal sulfate attack , since it reduces the compressive strength and increases the expansion of concrete. Consequently, the concrete structure may be damage .The effects of total and total effective sulfate contents on high strength concrete (HSC) have been studied in the present study.
The research studied the effect of sulfate content in cement , sand and gravel , as well as comparing the total sulfate content with the total effective SO3 content. Materials used were divided into two groups of SO3 in cement ,three groups of SO3 in sand ,and two groups of SO
... Show MoreOne of the most important problems that faces the concrete industry in Iraq is the deterioration due to internal sulfate attack , since it reduces the compressive strength and increases the expansion of concrete. Consequently, the concrete structure may be damage .The effects of total and total effective sulfate contents on high strength concrete (HSC) have been studied in the present study. The research studied the effect of sulfate content in cement , sand and gravel , as well as comparing the total sulfate content with the total effective SO3 content. Materials used were divided into two groups of SO3 in cement ,three groups of SO3 in sand ,and two groups of SO3 in gravel. The results show that considering the total effective sulfate con
... Show MoreThe 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.
In this work, a chemical optical fiber sensor based on Surface Plasmon Resonance (SPR) was designed and implemented using plastic optical fiber. The sensor is used for estimating refractive indices and concentrations of various chemical materials (methanol, distilled water, ethanol, kerosene) as well as for evaluating the performance parameters such as sensitivity, signal to noise ratio, resolution and the figure of merit of the fabricated sensor. It was found that the value of the sensitivity of the optical fiber-based SPR sensor, with 40 nm thick and 10 mm long Au metal film of exposed sensing region, was 3μm/RIU, while the SNR was 0.24, the figure of merit was 20, and the resolution was 0.00066. The sort of optical fiber utilized i
... Show MoreThe research aims to know the extent of the impact of the risks of foreign exchange centers represented in commitment risks, liquidity risks, and exchange rate risks on the continuity of the economic unit. The research in the light of its presentation of the intellectual, cognitive and applied contributions about the risks of foreign currency centers and the continuity of the economic unit, and represented the research community in the banking sector, and the sample included nine private commercial banks listed in the Iraq Stock Exchange, and they relied on the research on a time series consisting of four years that extended from one year 2017 to 2020. The research problem was the impact of the risks associated with foreign currency cent
... Show MoreThis paper addresses the substrate temperature effect on the structure, morphological and optical properties of copper oxide (CuO) thin films deposited by pulsed laser deposition (PLD) method on sapphire substrate of 150nm thickness. The films deposited at two different substrate temperatures (473 and 673)K. The atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and UV-VIS transmission spectroscopy were employed to characterize the size, morphology, crystalline structure and optical properties of the prepared thin films. The surface characteristics were studied by using AFM. It is found that as the substrate temperature increases, the grain size increased but the surface roughness decreased. The FTIR spec
... Show MoreThe research included preparation of new iron(II) complexes with mixed ligands including benzilazine(BA) and semicarbazone ligands {benzilsemicarbazone- BSCH or benzilbis(semicarba-zone)- BBSCH2 or salicylaldehydesemicarbazone- SSCH2 or benzoinsemicarbazone- B'SCH2}.by classical and microwave methods. The resulted complexes have been characterized using chemical and physical methods. The study suggested that the above ligands form ionic complexes having formulae [Fe(SCHi)(BA)(Cl)m](Cl)2-m {where SCH, BSCH, BBSCH2, SSCH¬2 or B'SCH2 ligands; m=1 or 2}. Hexacoordinated mononuclear complexes have been investigated by this study and having octahedral geometries. The effect of laser ray type visible region have been studied on solid ligands and
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