Objective: To evaluate the effect of mouth rinses (Biofresh and ZAK) on the surface micro hardness
of two light cure restorative material (Tetric ceram ivoclar-vivadent) and (3M Z 250) dental
composite.
Methodology: The microhardness values of (sixty) composite specimens were measured at the top
surfaces after 24 hours of immersion in different solutions (Biofresh, Zak mouth wash and distilled
water as control). Comparison done using descriptive statistics (mean, SD, SEM, minimum and
maximum values) and inferential statistics (ANOVA and LSD) test.
Results: The biofresh mouth rinse which has high alcohol containing has less effect on
microhardness of tetric ceram than the zak &distiled water , while the effect of Zak mouth rinse on
microhhybrid composit (3M Z250) is less than biofresh &distiled water, also there was highly
significant difference between subgroup of tetric ceram and the same for (3M Z250) composite & the
effect of the mouth rinse on hardness was material dependent it may be attributed to the differences
in chemical composition and filler type of each material. Since it was found that alcohol is not the only
factor that has the softening effect on the restorative material, other ingredient in a mouth rinse. may
have softening effect on polymer matrix.
Recommendations: We recommend for a comparison of color stability for restorative material
under the effect of mouth rinsing.
Research in Iraq has expanded in the field of material technology involving the properties of the lightweight concrete using natural aggregate. The use of the porcelinate aggregate in the production of structural light concrete has a wide objective
and requires a lot of research to become suitable for practical application. In this work metakaolin was used to improve compressive strength of lightweight porcelinate concrete which usually have a low compressive strength about 17 MPa . The effect of metakaolin on compressive, splitting tensile, flexure strengths and modulus of elasticity of lightweight porcelinate concrete have been investigated. Many experiments were carried out by replacing cement with different percentages of
met
In this paper the effect of mixing TiO2 nanoparticles with epoxy resin is studied. The TiO2 nanoparticles would be synthesis and characterized by scanning electron microscopy (SEM), XRD FTIR, for two particle sizes of 50 and 25 nm. The thermal conductivity is measured with and without composite epoxy resin; the results showed that the thermal conductivity was increased as nanoparticle concentration increased too. The thermal conductivity was increased as particle size decreased.
Construction joints are stopping places in the process of placing concrete, and they are required because in many structures it is impractical to place concrete in one continuous operation. The amount of concrete that can be placed at one time is governed by the batching and mixing capacity and by the strength of the formwork. A good construction joint should provide adequate flexural and shear continuity through the interface.
In this study, the effect of location of construction joints on the performance of reinforced concrete structural elements is experimentally investigated.
Nineteen beam specimens with dimensions of 200×200×950 mm were tested. The variables investigated are the location of the construction joints
... Show MoreThis experiment was performed to investigate the effect of dietary supplementation with linseed on egg quality of laying quail. A total of 320 9-week-old Japanese quail (Coturnix coturnix japonica) 9-wk old were allocated to 4 treatment groups with 4 replicates containing 20 quail each. Birds were fed a commercial diet containing 0% (C), 2% (T1), 4% (T2), or 6% (T3) linseed. Birds received water and diet ad libitum during the total period of the experiment. Egg quality characteristics were monitored over 3 consecutive 21-d periods. Egg quality criteria involved in this experiment were egg weight, yolk diameter, yolk height, yolk weight, albumen height, albumen weight, shell weight, shell thickness, Haugh unit, albumen percentage, yolk perce
... Show MorePermanent magnets of different intensities were used to investigate the effect of a magnetic field in the process of preventing deposits of calcium carbonate. The magnets were fixed on the water line from the tap outside. Then heating a sample of this water in flasks and measuring the amount of sediment in a manner weighted differences. These experiments comprise to the change of the velocity of water flow, which amounted to (0.5, 0.75, 1) m/sec through the magnetic fields that are of magnetic strength (2200, 6000, 9250, 11000) Gauss, and conduct measurements, tests and compare them with those obtained from the use of ordinary water.The results showed the effectiveness of magnetic treatment in reducing the rate of deposition of calcium carb
... Show MoreIn this work, HgBa2CaCu2-xSbxO8+δ compounds with (x = 0.2, 0.4, 0.6 and 0.8) have been prepared by the solid-state reaction method. Structural, morphological, and electrical properties were investigated using X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. Using the 4-probe technique to study the effect of antimony-substitution for Copper on the electrical properties of HgBa2CaCu2-xSbxO8+δ (Hg-1212) phase was investigated by measuring the resistivity as a function of temperature. Results indicate that the addition of antimony (Sb) increases the volume fraction of the phase and changes the superconducting transition temperature Tc of the superconductor to a normal state. The dielectric loss factor and ac
... Show MoreThe present study aimed to investigate effect of Pregabalin (PGB) on ovary tissue and number of follicles in female albino rats. Three groups of healthy adult female albino rats, fifteen rats in each group were used in current study. The rats of groups, G2 and G3 were administered orally with two doses 150 mg and 300mg/kg b.wt/day of pregabalin, respectively. The doses were given daily for 1 month, 2 months, and 3 months. Animals of group G1 (Control) were given saline alone. After the experimental periods, the rats were sacrificed and the isolated ovaries were histologically examined. The results of histological analysis of the ovaries in treated rats (G2, and G3) showed a significant (P≤0.05) decrease in the number of preantral, antral,
... Show MoreAbstract: This paper presents the results of the structural and optical analysis of CdS thin films prepared by Spray of Pyrolysis (SP) technique. The deposited CdS films were characterized using spectrophotometer and the effect of Sulfide on the structural properties of the films was investigated through the analysis of X-ray diffraction pattern (XRD). The growth of crystal became stronger and more oriented as seen in the X-ray diffraction pattern. The studying of X-ray diffraction showed that; all the films have the hexagonal structure with lattice constants a=b=4.1358 and c=6.7156A°, the crystallite size of the CdS thin films increases and strain (ε) as well as the dislocation density (δ) decreases. Also, the optical properties of the
... Show MoreThis study investigates the ionic conduction dependence on the size of alkaline cations in gel polymer electrolytes based on double iodide can enhance by incorporating a salt having a bulky cation.
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