Abstract: Objectives: To investigate the effect of temperature elevation on the bonding strength of resin cement to the zirconia ceramic using fractional CO2 laser. Background: Fractional CO2 laser is an effective surface treatment of zirconia ceramic, as it increases the bonding strength of zirconia to resin cement. Methods: Thirty sintered zirconia discs (10 mm diameter, 2 mm thickness) were prepared and divided to three groups (N=10) and five diffident pulse durations were used in each group (0.1, 0.5, 1, 5 and 10 ms). Group A was treated with 10 W power setting, group B with 20 W and group C with 30 W. During laser irradiation, temperature elevation measurement was recorded for each specimen. Luting cement was bonded to the treated zirconia surfaces and cured for 30 seconds. Shear bond strength was evaluated by a testing machine (universal) with bond failure mode determination. Results: The lowest temperature elevation measurement of the irradiated specimen which gave maximum shear bond strength was about 1.6±0.3 Ċ higher than ambient room temperature (27±0.2 ºC). Apparent micromechanical irregularities were seen in the treated samples and cracks formation with increased pulse duration and power setting were also observed. Conclusions: The temperature elevation is a vital factor in the surface roughness of zirconia ceramic with fractional CO2 laser irradiation and the lowest temperature elevation at best shear bond strength of zirconia ceramic to the resin cement is satisfied with the shorter pulse duration of 0.1 millisecond.
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Background: Acute urinary tract infection is a common bacterial infection causing illness in infants and children. At age of seven, 8% of girls and 2% of boys will have at least one episode. Although drinking water and using home remedies are known to help to flush away bacteria and keeps them from sticking to the bladder wall, researches to test the efficacy and safety of hydrochlorothiazide's diuretic effect as adjuvant to the antibiotics in pediatric age groups are lacking, and so this research was to address this subject.
Objectives: To assess the effectiveness and the safety of hydrochlorothiazide as adjuvant therapy to the antibiotics in treating acute urinary tract infect
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This study deals with the petrology of Injana Formation (Upper Miocene) at
Zawita, Amadia and Zakho areas. The sandstone of Injana Formation is of two
typesnamely, litharenite and feldspathiclitharenite. The rock fragments of Injana
Formation are mostly sedimentary and hence the sandstones are classified as
sedarenite and more specifically chertarenite owing to the predominance of chert
rock fragments. The sandstone is mineralogicallysubmature rangingfrom
mechanically and chemically stable tounstable. The petrographic studies reveal
nearness of source area with arid to semi-arid climate. The source rocks are
sedimentary, low- to medium-grade metamorphic and basic volcanic rocks. They are
mostly supplied from th
The effect of heat treatment on the optical properties of the bulk heterojunction blend nickel (II) phthalocyanine tetrasulfonic acid tetrasodium salt and Tris (8-hydroxyquinolinato) Aluminum (NiPcTs/Alq3) thin films which prepared by spin coating was described in this study. The films coated on a glass substrate with speed of 1500 rpm for 1.5 min and treated with different annealing temperature (373, 423 and 473) K. The samples characterized using UV-Vis, X ray diffraction and Fourier transform Infrared (FTIR) spectra, XRD patterns indicated the presence of amorphous and polycrystalline blend (NiPcTs/Alq3). The results of UV visible shows that the band gap increase with increasing the annealing temperature up to 373 K and decreases with
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Due to severe scouring, many bridges failed worldwide. Therefore, the safety of the existing bridge (after contrition) mainly depends on the continuous monitoring of local scour at the substructure. However, the bridge's safety before construction mainly depends on the consideration of local scour estimation at the bridge substructure. Estimating the local scour at the bridge piers is usually done using the available formulae. Almost all the formulae used in estimating local scour at the bridge piers were derived from laboratory data. It is essential to test the performance of proposed local scour formulae using field data. In this study, the performance of selected bridge scours estimation formulae was validated and sta
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This study deals with establishing the depositional environment of the Fatha Formation through facies analysis. It also deals with dividing the formation into units based on the rhythmic nature. Data from selected shallow wells near Hit area and deep wells at East Baghdad Oil field are used. Five major lithofacies are recognized in this study, namely, greenish grey marl, limestone, gypsum (and/or anhydrite), halite and reddish brown mudstone (with occasional sandstone).The limestone lithofacies is divided into three microfacies: Gastropods bioclastic wackestone microfacies, Gastropods peloidal bioclastic packstone, and Foraminiferal packstone microfacies.The lithofacies of the Fatha are nested in a rhythmic pattern or what is known as sh
... Show MoreCorruption, in all its categories and forms, is regarded as the nowadays virus which has greatly spread in most institutes and society, a matter that cause a great waste of resources.
According to the reports of international transparency Institute, Iraq is regarded as one of the greatest countries in corruption.
Regardless of the reasons and forms of corruption, the retreat in work – values and ethics are the main reasons behind that.
Being the main source of providing qualified staff "educators" for the working market, the high education institutes face great challenges in standing against corruption inside and outside
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This study includes six species related to the genus Echinops L. (composite) grown in Iraq which are listed below: E.armatus Boiss. & Hausskn., E. bicolor Nabelek, E. cephalotes DC., E.haussknechtii Boiss., E. moulensis Rech., E. nitens Bornm., the geographical distribution and ecological preferences' were documented.
It has been also observed that this genus was distributed near waterfalls, vallies, road side, dry limestone, clay soil and hard rocky soil in Different heights. The most separated species was E.armatus and the least separated one was E.haussknechtii, the species was listed in diagram and distributed on a map.
The Upper Campanian-Maastrichtian succession in Buzurgan oil field of Southeastern Iraq consists of Hartha and Shiranish formations. Three facies associations were distinguished in the studied succession. These include shallow open marine environment within the inner ramp, deep outer ramp and basinal environments. The Hartha Formation in the study area was deposited on a shallow carbonate platform with distally steepened ramp setting. The studied succession represents two 3rd order cycles. These cycles are asymmetrical and start with cycle A which is incomplete where the lower part of the Hartha Formation represents the deep outer ramp facies of the transgressive system tract.and the upper part of the Hartha Formation reflects deposition
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