Background: Cleaning and shaping of root canals successfully requires high volumes of irrigation solutions that can only be applied to the apical third of root canal after enlargement with instrument, so the aim of this study was to evaluate and to compare the efficiency of Maxi-I-probe (side-vented needle), in the amount of root canal irrigant penetration for five different master apical file sizes (MAF) and four different degrees of coronal and middle thirds flaring. Materials and Methods: Two hundred resin blocks with simulated root canals were used in this study and divided into 5 major groups (40 for each) based on the size of master apical files (#20, #25, #30, #35, and #40). Each major group was subdivided into 4 subgroups depending on different sizes and depth of flaring (10 for each).The instrumentation and flaring techniques were used as following: 1. without flaring group, root canal shape resembles shape of the master apical K-file, 2. flaring I group, flaring done with Gates Glidden I for 2 mm coronally, 3. flaring II group, flaring was done with Gates Glidden I for 4 mm coronally, Gates Glidden II for 2 mm, 4. flaring III group, flaring was done with Gates Glidden I for 6mm,Gates Glidden II 4mm and Gates Glidden III for 2 mm coronally. Irrigation was done with Max-i-probe gauge 28. Results: By comparing the five different master apical file sizes at four different degrees of flaring, there was an increase in the amount of irrigant penetration with increase MAF size, taper had more effect in small canals size and decreased with further enlargement of master apical file size until no benefit was achieved in large canals size. Conclusions: It was shown that, Max-i-probe had a limited amount of irrigant entrance. Flaring was more effective in small canals than the larger canals in an amount of irrigant entrance; increasing MAF size was effective in an increase amount of irrigant entrance.
Solar energy usage in Iraq is facing many issues; one of those is the accumulation “of the dust on the surface of the solar module which” would highly lower its efficiency. The present work study the effect of dust accumulation” on installing fixed solar modules with different inclined angles 15o, 33o, 45o, 60o. Evaluation of the solar modules performance under different circumstance conditions such as rain, wind and humidity are considered in study of dust effect on solar module performance. The results show that the lowest output average efficiencies of solar modules occurs at 15o horizontally inclined angle are 7.4% , 6.7% , 8.0% , 8.1%, and 8.4% for the cor
... Show MoreDue to the urgent need to develop technologies for continuous glucose monitoring in diabetes individuals, poten tial research has been applied by invoking the microwave tech niques. Therefore, this work presents a novel technique based on a single port microwave circuit, antenna structure, based on Metamaterial (MTM) transmission line defected patch for sensing the blood glucose level in noninvasive process. For that, the proposed antenna is invoked to measure the blood glu cose through the field leakages penetrated to the human blood through the skin. The proposed sensor is constructed from a closed loop connected to an interdigital capacitor to magnify the electric field fringing at the patch center. The proposed an tenna sensor i
... Show More
(5)
(4)
Dam operation and management have become more complex recently because of the need for considering hydraulic structure sustainability and environmental protect on. An Earthfill dam that includes a powerhouse system is considered as a significant multipurpose hydraulic structure. Understanding the effects of running hydropower plant turbines on the dam body is one of the major safety concerns for earthfill dams. In this research, dynamic analysis of earthfill dam, integrated with a hydropower plant system containing six vertical Kaplan turbines (i.e., Haditha dam), is investigated. In the first stage of the study, ANSYS-CFX was used to represent one vertical Kaplan turbine unit by designing a three-dimensional (3-D) finite element (F
... Show More
(12)
(9)
Thermal conductivity of compacted bentonite is one of the most important properties where this type of clay is proposed for use as a buffer material. In this study, Lee's disc method was used to measure the thermal conductivity of compacted bentonite specimens. The experimental results have been analyzed to observe the three major factors affecting the thermal conductivity of bentonite buffer material. While the clay density reaches to a target value, the measurement is taken to evaluate the thermal conductivity. By repeating this procedure, a relationship between clay dry density and thermal conductivity has been established in specimens after adjusting the water contents of the bentonite by placing its specimens in a drying oven for diffe
... Show More
(1)
The current study included the anatomical structure of the metatarsal bone in sheep in terms of the traditional structural description of the bone, as it was found that the metatarsal bone in the fore and hind limbs of adult sheep had no visible differences between it and animals, especially ruminants. The metacarpal \tarsal bone No. 3 was cylindrical in shape, with the presence of the metacarpal \tarsal bones 2 and 4 declines, articulated from the proximal end with the metacarpal and metatarsal bones whereas from the distal part with the fetlock joint and the first phalanx bone. The aim of the study is to determine whether the environment and its changes in Iraq have affected the animals and their bones in terms of length, thicknes
... Show More
Iron-Epoxy composite samples were prepared by added
different weight percentages (0, 5, 10, 15, and 20 wt %) from Iron
particles in the range of (30-40μm) as a particle size. The contents
were mixed carefully, and placed a circular dies with a diameter of
2.5 cm. Different mechanical tests (Shore D Hardness, Tensile
strength, and Impact strength ) were carried out for all samples. The
samples were immersed in water for ten weeks, and after two weeks
the samples were take-out and drying to conducting all mechanical
tests were repeated for all samples. The hardness values increased
when the Iron particle concentration increased while the Impact
strength is not affected by the increasing of Iron particles
c
