Introduction: The present study was performed to evaluate the influence of a 1064 nm fiber laser on shear bond strength (SBS) at the interface of titanium and resin cement. Methods: Forty titanium discs of 6 mm × 3 mm (diameter and thickness respectively) were categorized into four groups (n=10): control group without any surface treatment and three groups treated with a fiber laser with 81 ns pulse duration, 30 kHz frequency, 10000 mm/s scanning speed, 0.05 mm spot size, and different average power values (3, 5 and 7 W) depending on the tested group. Titanium disc characterization was performed by the scanning electron microscope (SEM) and surface roughness tester. Phase analysis was achieved using an X-ray diffractometer (XRD). Following these tests, resin cement application to titanium discs was performed. SBS values were determined by the universal testing machine. After debonding, the surface of titanium discs was examined by the stereomicroscope for the determination of failure modes. Data analysis was performed using analysis of variance (ANOVA) and Tukey HSD tests (α=0.05). Results: A higher surface roughness value was observed in the 7 W group followed by the 5 W and 3 W groups, and the lowest surface roughness was in the control group. Additionally, the lowest SBS value was obtained from the control group and the highest SBS value was obtained from the 7 W group followed by the 5 W and 3 W groups. Conclusion: SBS between titanium abutment and resin cement can be significantly enhanced by using a fiber laser as a surface treatment considering tested laser parameters; additionally, a positive association between surface roughness and SBS was noted in the experimental groups.
Background: The formation of white spot lesions around fixed orthodontic attachments is a common complication during and after fixed orthodontic treatment, which hinders the result of a successfully completed orthodontic treatment. The aim of the study was to assess the effectiveness of the Caries Infiltrant (ICON®) on prevention of caries on the smooth enamel surface when applied alone or combined with conventional adhesives. Materials and methods: Seventy eight human premolar enamel discs were randomly assigned to six groups (n=13). The discs were etched and treated with resins of different monomer content forming the following groups: (1)Untreated etched samples served as the negative control, (2) ICON® (DMG), (3) Adper™ S
... Show MoreThe V2O5 films were deposited on glass substrates which produce using "radio frequency (RF)"power supply and Argon gas technique. The optical properties were investigated by, UV spectroscopy at "radio frequency" (RF) power ranging from 75 - 150 Watt and gas pressure, (0.03, 0.05 and 0.007 Torr), and substrate temperature (359, 373,473 and 573) K. The UV-Visible analysis shows that the average transmittance of all films in the range 40-65 %. When the thickness has been increased the transhumance was decreased from (65-40) %. The values of energy band gap were lowered from (3.02-2.9 eV) with the increase of thickness the films in relation to an increase in power, The energy gap decreased (2.8 - 2.7) eV with an increase in the pressure and
... Show MoreThin films Tin sulfide SnS pure and doped with different ratios of Cu (X=0, 0.01, 0.03 and 0.05) were prepared using thermal evaporation with a vacuum of 4*10-6mbar on two types of substrates n-type Si and glass with (500) nm thickness for solar cell application. X-ray diffraction and AFM analysis were carried out to explain the influence of Cu ratio dopant on structural and morphological properties respectively. SnS phase appeared forming orthorhombic structure with preferred orientation (111), increase the crystallinity degree and surface roughness with increase Cu ratio. UV/Visible measurement revealed the decrease in energy gap from 1.9eV for pure SnS to 1.5 for SnS: Cu (0.05) making these samples suitable f
... Show MoreRooting response in stem cuttings of mung bean increased considerably with inresing
seedling age, due to endogenous IAA or supplied IBA. However, after the day 7- or 8-old of
seedling age. The cotyledons sheivel and drop-off spontaneously at day-8 of seedling age. So
that cotyledons excision after cuttings were made during the period between seedling
emergence (the day 4) and cotyledons dropping off (which starts at day 8 and its completion
at day 10) causes decrease in rooting at any time during cutting treatment ,in particular, at
zero time . In addition, results of this study revealed that terminal buds do not influence
significantly adventitious root formation whether IBA supplied or not. Whereas in leafless
c
In this work, Titanium oxide thin films doped with different concentration of CuO (0,5,10, 15,20) %wt were prepared by pulse laser deposition(PLD) technique on glass substrates at room temperature with constant deposition parameter such as : pulse (Nd:YAG), laser with λ=1064 nm, constant energy 800 mJ , repetition rate 6 Hz and No. of pulse (500). The structure , optical and electrical properties were studied . The results of X-ray diffraction( XRD) confirmed that the film grown by this technique have good crystalline tetragonal mixed anatase and rutile phase structure, The preferred orientation was along (110) direction for Rutile phase. The optical properties of the films were studied by UV-VIS spectrum in the range of (360-1100)
... Show MoreUnderstanding the effects of fear, quadratic fixed effort harvesting, and predator-dependent refuge are essential topics in ecology. Accordingly, a modified Leslie–Gower prey–predator model incorporating these biological factors is mathematically modeled using the Beddington–DeAngelis type of functional response to describe the predation processes. The model’s qualitative features are investigated, including local equilibria stability, permanence, and global stability. Bifurcation analysis is carried out on the temporal model to identify local bifurcations such as transcritical, saddle-node, and Hopf bifurcation. A comprehensive numerical inquiry is carried out using MATLAB to verify the obtained theoretical findings and und
... Show MoreGames engagement has become one of the main concerns in game industry. Early study revealed that Malaysian digital traditional games are suffering with the same issue due to several factors. One of it is the lack of the game itself. Although many Malaysian traditional games have been digitized, none of them has incorporated rewards despite its importance in games engagement. Realizing the importance of rewards in games engagement, one of Malaysian traditional Congkak has been chosen to be enhanced by incorporating rewards. Experiments have been conducted among 50 gamers among the Millennials. Prior interview, game demo and human test are conducted. Experiments focused on the influence of rewards on games flow, games challenge, and its ef
... Show MoreIn this study, nanocomposites have been prepared by adding
multiwall carbon nanotubes (MWCNTs) with weight ratios (0, 2, 3,
4, 5) wt% to epoxy resin. The samples were prepared by hand lay-up
method. Influence of an applied load before and after immersion in
sodium hydroxide (NaOH) of normality (0.3N) for (15 days) at
laboratory temperature on wear rate of Ep/MWCNTs
nanocomposites was studied. The results showed that wear rate
increases with increasing the applied load for the as prepared and
immersed samples and after immersion. It was also found that epoxy
resin reinforced with MWCNTs has wear rate less than neat epoxy.
The sample (Ep + 5wt% of MWCNTs) has lower wear rate. The
immersion effect in base so
In this study, silver nanoparticles (AgNPs) were synthesized using a cold plasma technique and a plasma jet. They were then used to explore how photothermal treatment may be used to treat lung cancer (A549) and normal cells (REF) <i>in vitro</i>. The anti-proliferative activity of these nanoparticles was studied after A549 cells were treated with (AgNPs) at various concentrations (100%, 50%, or 25%) and exposure times (6 or 8 min) of laser after 1 h or 24 h from exposed AgNPs. The highest growth inhibition for cancer cells is (75%) at (AgNPs) concentration (100%) and the period of exposure to the laser is (8 min). Particle size for the prepared samples varied according to the diameter o
... Show MoreThe semiconductor ZnO is one of II – VI compound group, it is prepare as thin films by using chemical spray pyrolysis technique; the films are deposited onto glass substrate at 450 °C by using aqueous zinc chloride as a spray solution of molar concentration 0.1 M/L. Sample of the prepared film is irradiating by Gamma ray using CS 137, other sample is annealed at 550°C. The structure of the irradiated and annealed films are analyzed with X-ray diffraction, the results show that the films are polycrystalline in nature with preferred (002) orientation. The general morphology of ZnO films are imaged by using the Atomic Force Microscope (AFM), it constructed from nanostructure with dimensions in order of 77 nm.
The optical properties o