The aerodynamic characteristics of the forward swept wing aircraft have been studied theoretically and an experimentally investigation for the wake field generated by this configuration have been carried out. Low order panel method with the Dirichlet boundary condition have been used to solve the case of the steady, inviscid and compressible flow. Two different panel method techniques have been employed: the source-doublet and the doublet method. The thickness for the various components was considered in the study. Prandtl-Glauert similarity rule has been used to account for the compressibility effects. Experimentally, a model was manufactured from wood with body length (290mm) and main wing span was (204mm). The primary objective of the experimental work was the measurements of the wake dimensions and orientation, velocity distribution along the wake and the wake thickness and growth. The experiments were conducted to four different configurations at four angles of attack. A blower type low speed wind tunnel with solid walls was used in the experimental work. The mean velocity at the test section was (9.3 m/s) and the Reynolds number based on the mean aerodynamic chord was (0.46x105). The measurements showed the existence of a three-dimensionality behavior in the wake flow field. Interference between the canard wake and the wing wake was observed. The canard effect on the wing root area was detected as the separation at the wing root was delayed due to the canard downwash. The velocity defect and wake thickness are increased with the increase of the angle of attack. The comparison of the numerical results with the other published data showed that the method is capable of predicting the aerodynamic coefficients for complex configurations with reasonable accuracy. The source-double method was more accurate and faster than the doublet method for the same number of panels. The aerodynamic coefficients for the forward swept wing aircraft was calculated using the real wake shape measured in the experimental work. Numerical results showed that the canard extended the range of the angle of attack for the aircraft with a significant improvement for the lift curve slope compared to the aircraft without the canard.
Background: Bisphosphonates are potent inhibitors of osteoclastic bone resorption and widely used for the treatment of osteoporosis, and osteogenesis imperfecta in children. Clinical and experimental studies have demonstrated that Bisphosphonates delay or inhibit tooth eruption. This study tries to focus on the effect of bisphosphonate on teeth development and jaw bones growth. Materials and methods: The present study includes 65 neonatal rats during lactation period from 15 Albino Wister rats mother. Alendronate (one type of Bisphosphonates) was administrated orally (15 mg/kg) into 10 pregnant rats two times a week, while other 5 rats regard as control. Then the neonatal rats sacrificed in I, 6, 11, 16 and 21 days. The lower first molar we
... Show MoreOf the new concepts introduced by the decree of the amendment of the French Civil Code No. 131-2016 issued on 10 February 2016, which raised a debate in jurisprudence both at the level of French jurisprudence or the Arab, the concept of (the content of the contract), which seems to have emerged from the appearance of new legal articles ( 1162-1171) is the cornerstone of the contract and the contract in the contract, the two pillars which, over the course of 200 years and a half, have been one of the main pillars of the codification of Napoleon. Is that the decree of amendment has already abandoned these two pillars, or most of what he did is a change in terminology while preserving the content of these two pillars implicitly, this is what w
... Show MoreBackground: The marginal adaptation has a key role in the success and longevity of the fixed dental restoration, which is affected by the impression and the fabrication techniques .The objective of this in vitro study was to evaluate and compare the marginal fitness of lithium disilicate crowns using two different digital impression techniques (direct and indirect techniques) and two different fabrication techniques (CAD/CAM and Press techniques). Materials and Methods: Thirty two sound upper first premolar teeth of comparable size extracted for orthodontic reason were selected in this study .Standardized preparation of all teeth samples were carried out with modified dental surveyor to receive all ceramic crown restoration with 1 mm deep
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The study aimed to reveal the role of social capital represented by its dimensions (structural, relational, and cognitive) in strengthening the management of excellence in Azadi Hospital / Duhok. In order to reach the goal of the study, the study variables were highlighted in theory through framing concepts and literary contributions for researchers in this field, In the field, the questionnaire was used as a basic tool to collect data from the individuals in the research sample who were represented by officials and individuals working from administrators and technicians, as (120) forms were distributed to the respondents, and (110) were retrieved from them in a way that is valid for analysis. Several statistical methods have bee
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Background: This in vitro study was carried out to evaluate the effect of various endodontic irrigants (sodium hypochlorite, ethylene diaminetetracetic acid and normal saline) on sealing ability of (Biodentine, mineral trioxide aggregate, and amalgam) used to repair furcal perforations. Material and methods: One hundred and twenty extracted human molars with divergent roots were used in this study. A standard root canal access cavity was prepared in each tooth and furcal perforation was made and was standardized by using k file size 100 instrument to get a perforation of (1.32mm) in diameter .The teeth were randomly divided in to three groups of 40 teeth according to the type of material used to repair the perforations (Group A: The furcal
... Show MoreBackground: Ceramic veneers represent the treatment of choice in minimally invasive esthetic dentistry; one of the critical factors in their long term success is marginal adaptation. The aim of the present study is to evaluate the marginal gap of ceramic veneers by using two different fabrication techniques and two different designs of preparation. Material and methods: A typodont maxillary central incisor used in the preparation from which metal dies were fabricated, which were in turn used to make forty stone dies. The dies divided into four experimental groups, each group had ten samples: A1: prepared with butt-joint incisal reduction and restored with IPS e.max CAD, A2: prepared with overlapped incisal reduction and restored with IPS e.
... Show MoreThis work is focused on studying the effect of liquid layer level (height above a target material) on zinc oxide nanoparticles (ZnO and ZnO2) production using liquid-phase pulsed laser ablation (LP-PLA) technique. A plate of Zn metal inside different heights of an aqueous environment of cetyl trimethyl ammonium bromide (CTAB) with molarity (10-3 M) was irradiated with femtosecond pulses. The effect of liquid layer height on the optical properties and structure of ZnO was studied and characterized through UV-visible absorption test at three peaks at 213 nm, 216 nm and 218 nm for three liquid heights 4, 6 and 8 mm respectively. The obtained results of UV–visible spectra test show a blue shift accomp
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The target of this study was to synthesize several new Ciprofloxacin drug analogs by providing a nucleophilic substitution procedure that provides new functionality at the carboxylic group location. The analogs were synthesized, designed, and characterized by 1HNMR, and FTIR. The synthetic path began from the reaction of ciprofloxacin drug with morpholine to give compound[B], ciprofloxacin derivative was linked with a variety of primary and secondary amines to give compounds[B1-B9]. The above-mentioned prepared compounds [B3 and B5] were applied to liver enzymes, and the increase in the activity of these enzymes was observed. In addition, a theoretical study was conducted to study the energies and properties of the prepared co
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The research represents an applied study to the urban scene of Baghdad city center within the area of (Al Bab Al Sharqi – Al Tahrir Square) through studying and identifying the levels of the reciprocal correlation of advertising signs impact on urban scene , then finding out the indicators and potential values which have made advertising signs as positive value by achieving the mechanisms of visual quality or a negative value by achieving mechanisms of visual pollution. And then examining the resulted visual perception defect reforming mechanism from it and identify the basic elements represented of the laws and legislation known worldwide. When presenting the problem, The research depends on: (Lack of clear perception
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