Background: The main drawback of soft lining materials was that they debonded from the denture base after a certain period of usage. Therefore, the purpose of this research was to determine the impact of oxygen and argon plasma treatment on the shear bonding strength of soft liners to two different kinds of denture base materials: conventional acrylic resin and high impact acrylic resin. Materials and Methods: Heat cure conventional and high impact acrylic blocks (40 for each group) were prepared. A soft liner connected the final test specimen of two blocks of each acrylic material. Shear bond strength (SBS) was assessed using universal testing machine. Additional blocks were also prepared for analyzing Vickers microhardness, contact angle, FTIR and AFM. The results were statistically analyzed using paired-sample T-test and independent-samples T-test (α=0.05). Results: The results showed a highly significant increase in SBS following plasma treatment with the highest mean value observed in plasma treated high impact acrylic specimen. Along with a significant rise in wettability, while microhardness was preserved. Conclusion: In conclusion, oxygen and argon plasma treatment was significantly effective in enhancing the SBS between soft liner and acrylic materials.
Background: The bond strength of endodontic sealers with dentin is a very important property for maintaining the integrity and seal of the root canal filling. The aim of this study was to evaluate and compare the effect of various irrigants (QMix, 17% EDTA and 2.5% NaOCl) on the push-out bond strength of AH plus and Bioceramic sealers. Materials and methods: Forty eight freshly extracted maxillary first molars human teeth with striaght palatal root were used in the study. The collected samples were randomly divided into three groups of equal sample size (n=16), according to the final irrigation regimen as follows: Group (1): QMix 2 in 1, Group (2): 17% ethylenediaminetetraacetic acid, Group (3): 2.5% sodium hypochloride. All samples were
... Show MoreTreatment of a high strength acidic industrial wastewater was attempted by activated carbon
adsorption to evaluate the feasibility of yielding effluents of reusable qualities. The experimental
methods which were employed in this investigation included batch and column studies. The
former was used to evaluate the rate and equilibrium of carbon adsorption, while the latter was
used to determine treatment efficiencies and performance characteristics. Fixed bed and expanded
bed adsorbers were constructed in the column studies. In this study, the adsorption behavior of acetic acid onto activated carbon was examined as a function of the concentration of the adsorbate, contact time and adsorbent dosage. The adsorption data was mo
Four localities were selected in Euphrates River and Ramadi sewage treatment plant to collect water samples monthly during the period between October 2001 to July 2002 . Total cell count of phytoplankton and its physico- chemical concentrations were determined . The study aimed to demonstrate the effect of Ramadi sewage treatment plant on Euhprates River . It is concluded that the sewage had an dilution effect for the total hardness , total alkalinity , electrical conductivity and salinity of Euphrates River , but it is also caused in the presence of a contaminated area . This was cleared from the depletion of dissolved oxygen and high values of biological oxygen demand with lower valuse of pH in this area . The water of Euphrates
... Show MoreThe long – term behaviour of polyethylene products used out doors is affected by weathering. In the present work,
weathering test was carried out to find the effect of the environment conditions on the mechanical properties of
HDPE/LLDPE blends with different weight percents (0, 15, 30, and 45 %) relative to the LLDPE by increasing the
exposure times to (100, 150, 200, 250, 300) hr.
A series of tests (destructive), tensile, impact and hardness were carried out on the prepared samples, the results
obtained declare the changes on the material behaviour from ductile to brittle and the polymer shows a decline in the
mechanical properties with increasing the exposure times.
In the present work empirical equations were r
Due to the low cost of both unsaturated polyester resin and the plant fibers along with protect of the environment, the wasted Carrot fibers were employed in this study to strengthen and color the resin. Carrot peels powders have been incorporated with unsaturated polyester/ natural fibers (UPE/C.F) gel coats to form a good candidate with good mechanical behaviors in different industrial applications. The wasted carrot peels fibers, were dried, crashed and milled into micro particles sizes (2.5% microns) to improve the mechanical properties (impact energy, Compressive load and Elastic Modulus) of unsaturated polyester. Micro carrot fibers (C.F) have been loaded to unsaturated fibers a
Orthogonal polynomials and their moments serve as pivotal elements across various fields. Discrete Krawtchouk polynomials (DKraPs) are considered a versatile family of orthogonal polynomials and are widely used in different fields such as probability theory, signal processing, digital communications, and image processing. Various recurrence algorithms have been proposed so far to address the challenge of numerical instability for large values of orders and signal sizes. The computation of DKraP coefficients was typically computed using sequential algorithms, which are computationally extensive for large order values and polynomial sizes. To this end, this paper introduces a computationally efficient solution that utilizes the parall
... Show More(Cu1-x,Agx)2ZnSnSe4 alloys have been fabricated with different Ag content(x=0, 0.1, and 0.2) successfully from their elements. Thin films of these alloys have been deposited on coring glass substrate at room temperature by thermal evaporation technique under vacuum of 10-5Torr with thickness of 800nm and deposition rate of 0.53 nm/sec. Later, films have been annealed in vacuum at (373, and 473)K, for one hour. The crystal structure of fabricated alloys and as deposited thin films had been examined by XRD analysis, which confirms the formation of tetragonal phase in [112] direction, and no secondary phases are founded. The shifting of main polycrystalline peak (112) to lower Bragg’s angle as compared to Cu2ZnSnSe4 angle refers to incorpora
... Show MoreIn the present study, histological study was carried out on adult chickens to shed light on the effects of GH and IGF-1 on the heart, liver, and gizzard. The microscopic examination had shown that GH and IGF1 promote protein synthesis in the heart tissue. The herein work referred to the presence of a considerable amount of adipose tissue among the bundles of cardiac muscles, which is related to the metabolic process. The results also revealed that GH and IGF-1 promote both protein synthesis and Mitosis in the tissues of the liver and gizzard Moreover, the above hormones stimulate apoptosis, regeneration and secretory activity in gizzard secretory glands
Mechanical and thermal properties of composites, consisted of unsaturated polyester resin, reinforced by different kinds of natural materials (Orange peels and Date seeds) and industrial materials (carbon and silica) with particle size 98 µm were studied. Various weight ratios, 5, 10, and 15 wt. % of natural and industrial materials have been infused into polyester. Tensile, three-point bending and thermal conductivity tests were conducted for the unfilled polyester, natural and industrial composite to identify the weight ratio effect on the properties of materials. The results indicated that when the weight ratio for polyester with date seeds increased from 10% to 15%, the maximum Young’s modulus decreased by 54%. When the weight rat
... Show MoreIn the present study, MIG welding is carried out on low carbon steel type (AISI 1015) by using electrode ER308L of 1.5mm diameter with direct current straight polarity (DCSP). The joint geometry is of a single V-butt joint with one pass welding stroke for different plate thicknesses of 6, 8, and 10 mm. In welding experiments, AISI 1015 plates with dimensions of 200×100mm and edge angle of 60o from both sides are utilized. In this work, three main parameters related to MIG welding process are investigated, which are welding current, welding speed, heat input and plate thickness, and to achieve that three groups of plates are employed each one consists of three plates. The results indicate that increasing the weld heat input (t
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