It is found that hypersensitive teeth have a larger number and wider patent tubules than those of non-sensitive teeth. Objective: The aim of this study is to compare between the effects of diode laser at different power densities, with and without sodium fluoride on the sealing of exposed dentinal tubules and dentin permeability. Materials and methods: 118 teeth were used. Samples were divided into three major groups. The first consisted of 100 teeth used for permeability test. The second consisted of 16 teeth for measuring external surface temperature elevation while irradiation. The third, in turn, consisted of one pair of teeth observed under SEM for dentine surface morphology analysis. Results: For dentin permeability measurement, the results revealed a highly significant difference between the control group and 2, 3 W with varnish groups. For the external surface temperature elevation, the results revealed that temperature rise, for both laser alone and with varnish groups, was between (67-97.9 ∘C) at 1.6, 2 W. SEM analysis revealed that approximately optimum sealing of tubules occurred in 2W with the varnish group. Conclusions: The combined application of 940 nm diode laser at 2W with 809.7 W/cm² power densities, with sodium fluoride white varnish show a significant improvement in their effects on dentin permeability reduction as compared to each treatment alone.
This paper discusses Ree–Eyring fluid’s peristaltic transport in a rotating frame and examines the impacts of Magnetohydrodynamics (MHD). The results deal with systematically (analytically) applying each of the governing equations of Ree–Eyring fluid, the axial and secondary velocities, flow rate due to auxiliary stream, and bolus. The effects of some distinctive variables, such as Hartman number, heat source/sink, and amplitude ratio, are taken under consideration and illustrated through graphs.
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In this work, a composite material was prepared from Low-density polyethylene (LDPE) with different weight percent of grain and calcinations kaolin at temperature of (850oC) using single screw extruder and a mixing machine operated at a temperature between (190-200oC). Some of mechanical and physical properties such as tensile strength, tensile strength at break, Young modulus, and elongation at break, shore hardness and water absorption were determined at different weight fraction of filler (0, 2, 7, 10 and 15%). It was found that the addition of filler increases the modulus of elasticity, elongation at break, shore hardness and impact strength; on other hand, it decreases the tensile strength and tensile strength
... Show MoreThis experiment was carried out in the field of botanical garden which belongs to Biologi
Department , College of Education (Ibn Al-Haitham), University of Baghdad during the
growing season 2009-2010.The experiment was designed to study the effect 5 concentrations
of Gibberellic acid(GA3)( 25,50,75,100and125mg.L
-1
) and 2 levels of NPK (17:17:17)
fertilizer (200 and 400 Kg.ha
-1
) and their interaction on the rates of absorption and transport
of some macronutrient elements in two varieties of chamomile plant ( Local variety ,
Matricaria chamomilla L. and German variety , Matricaria recutitia L.) . Randomized
Complete Block Design (RCBD) was used with 3 replicates for each treatment .Control plants
Investment in high education is considered to be most important factors of production which the return an individual and social than economic returns found by searching the growing problem of unemployment, especially among youth graduates, where the unemployment rate in 2010 (50%) of these high rates have led to increased migration of scientific minds graduate recently, "to search for job opportunities outside Iraq for not hiring functions and this is in vain" clear "in the human and financial resources lead to structural imbalances in the Iraqi economy. When calculating the correlation coefficient between the graduates and the unemployment rate where it reached (0.21) emerged from the results of
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The research aims at identifying the importance of scientific research for researchers and in creating new knowledge، development and utilization of mental and cognitive energies and developed them with the ability to research، extrapolation، meditation and then conclusion. The information was collected by interviewing the Secretary-General of the Central Library and by distributing questionnaire forms to the (33) teaching staff of the College of Higher Education. The responses of the society were analyzed the result and the recommendations were the most important 1. Information specialist and all employees of the administrators and technicians in the centers of information sources (libraries) and in the field are considered scientific r
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The problem of informal settlements in Iraqi is one of the most serious problems due
to its economic, social and security impacts which jeopardize the society safety and stability.
This study investigates the present situation of informal settlements in the Baghdad
governorates as well as approaches followed in making decisions to either upgrade or remove
those areas. Requirements of each decision are also discussed.
Study methods relied on both office and field studies to collect data and information
needed. The study revealed important findings that would help take appropriate measures that
deal with the informal settlements in Iraqi. The study also proposes effective mechanisms to
preclude both an increase in c
ABSTRACT
A field experiment was carried out in the fields of the college of agricultural engineering sciences, university of Baghdad during the fall season of 2021, in order to find out which of the cultivated genotypes of maize are efficient under nitrogen fertilization. The experiment was applied according to a RCBD (split plot design with three replications). The genotypes of experiment (Baghdad, 5018 and Sarah) and supplying three levels of nitrogen fertilizer, which are N1 (100 kg/ha), N2 (200 kg/ha) and N3 (300 kg/ha), the results of the statistical analysis are showed the superiority of the cultivar Sarah in the trait of number of days until 50% silking, chlorophyll
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