In this work, nanostructure porous silicon surface was prepared using electrochemical etching method under different current densities. I have studied the surface morphology and photoluminescence (PL) of three samples prepared at current densities 20, 30 and 40 mA/cm2 at fixed etching time 10 min. The atomic force microscopy (AFM) images of porous silicon showed that the nanocrystalline silicon pillars and voids over the entire surface has irregular and randomly distributed. Photoluminescence study showed that the emission peaks centered at approximately (600 – 612nm) corresponding energies (2.06 – 2.02eV).
While current-voltage characteristics shows, as the current density increase the current flow in the forward bias is decreasi

Background: The present study was carried out to compare shear bond strength of sapphire bracket bonded to zirconium surface after using different methods of surface conditioning and assessment of the adhesive remnant index. Materials and methods: The sample composed of 40 zirconium specimens divided into four groups; the first group was the control, the second group was conditioned by sandblast with aluminum oxide particle 50 μm, the third and fourth group was treated by (Nd: YAG) laser (1064nm)(0.888 Watt for 5 seconds) for the 1st laser group and (0.444 Watt for 10 seconds) for the 2nd laser group. All samples were coated by z-prime plus primer. A central incisor sapphire bracket was bonded to all samples with light cure adhesive res

Background: Large amounts of oily wastewater and its derivatives are discharged annually from several industries to the environment. Objective: The present study aims to investigate the ability to remove oil content and turbidity from real oily wastewater discharged from the wet oil's unit (West Qurna 1-Crude Oil Location/ Basra-Iraq) by using an innovated electrocoagulation reactor containing concentric aluminum tubes in a monopolar mode. Methods: The influences of the operational variables (current density (1.77-7.07 mA/cm2) and electrolysis time (10-40 min)) were studied using response surface methodology (RSM) and Minitab-17 statistical program. The agitation speed was taken as 200 rpm. Energy and electrodes consumption had been studi

Research was conducted to study the effect of proline and aspirin with 10 and 20 ppm on seed germination and seedling growth of Lycopersicon esculentumand the effect of surface growthof Fusarium oxysporum.The results showed that the proline and aspirin effected significantly to decreased percentage of seed germination, acceleration of germination, promoter indicator, elongation speed of radical and plumule and also the infection percentage of seed decay and surface growth of Fusarium oxysporumwas reduced significantly.

Background: this study aimed to evaluate the effect of addition of hydroxyapatite micro filler in three concentrations (5%, 10%, 15%) on surface roughness, impact strength, flexural strength and hardness. Material and methods: One hundred sixty acrylic samples were used in this study,40 samples were used for each test(impact strength ,flexural strength ,hardness and surface roughness).The test group divided into four subgroups(n=10) for controlgroup,5%,10% ,15%H,A.concentration addition groups .Impact testing device, flexural strength testing device, shore hardness tester and profilometer device were used to measure the four tests examined in this study. Results: the results showed a significant increase in impact strength, hardness in all

This work involves the development of ceramic coating to steel surfaces (enamel).This enamel high quality consisted of two ceramic layers to ensure excellent bonding with the steel surfaces. The first is called the ground coat which proved bonding between the steel base and the second outer layer called the cover coat. Various concentrations of TiO2 were separately added to the mixture of the cover coat, resulting in to much better densification of the ceramic outer layer, the hardness, thermal shock resistances, and glossiness were improved also .Moreover this addition has raised the corrosion resistances of the ceramic in harsh acidic environment and at higher temperatures Also this enamel was used to protect the surfaces of steels whi

The zirconia ceramic restoration (ZCR) is used as substitutes for the metal-ceramic restoration. Clinical studies demonstrating of ZCRs showed a high fracture incidence of veneering layer than metal-ceramic restorations. This attributed to the low bond strength of zirconia to veneering ceramic as a result of lacking of glass content in its matrix. Surface treatment was proposed to improve the bonding strength between zirconia and veneering ceramic. Several studies revealed that some treatment such as airborne particle abrasion (APA) is responsible for generating chipping of veneering ceramic. The study aimed to develop a new zirconia coatings to increase bonding strength between zirconia substrate and veneering porcelain. Three groups of 15

Photonic Crystal Fiber (PCF) based on the Surface Plasmon Resonance (SPR) effect has been proposed to detect polluted water samples. The sensing characteristics are illustrated using the finite element method. The right hole of the right side of PCF core has been coated with chemically stable gold material to achieve the practical sensing approach. The performance parameter of the proposed sensor is investigated in terms of wavelength sensitivity, amplitude sensitivity, sensor resolution, and linearity of the resonant wavelength with the variation of refractive index of analyte. In the sensing range of 1.33 to 1.3624, maximum sensitivities of 1360.2 nm ∕ RIU and 184 RIU⁻¹ are achieved with the high sensor resolutions of 7

This paper investigated the treatment of textile wastewater polluted with aniline blue (AB) by electrocoagulation process using stainless steel mesh electrodes with a horizontal arrangement. The experimental design involved the application of the response surface methodology (RSM) to find the mathematical model, by adjusting the current density (4-20 mA/cm2), distance between electrodes (0.5-3 cm), salt concentration (50-600 mg/l), initial dye concentration (50-250 mg/l), pH value (2-12 ) and experimental time (5-20 min). The results showed that time is the most important parameter affecting the performance of the electrocoagulation system. Maximum removal efficiency (96 %) was obtained at a current density of 20 mA/cm2, distance be