Background: The polymethyl methacrylate is the most reliable material for the construction of complete and partial dentures, despite satisfying esthetic demand itsuffered from having unsatisfactory properties like impact strength and transverse strength. This study was designed to improve the impact strength and transverse strength of heat cure acrylic resin by adding untreated and oxygen plasma treated polypropylene fibers and investigate the effect of this additive on some properties of acrylic resin materials. Materials and methods: Untreated and oxygen plasma treated polypropylene fibers was added to PMMA powder by weight 2.5 %. Specimens were constructed and divided into 5 groups according to the using tests; each group was subdivided in to 3 subgroups. The tests conducted were impact strength, transverse strength, surface hardness, surface roughness, water sorption and solubility. Data were analyzed by one way analysis of variance (ANOVA) and least significant differences (LSD). Results: After incorporation of untreated and oxygen plasma treated polypropylene fibers there was a highly significant increase in impact strength and surface hardness; while there was a non significant difference in transverse strength. Also the value of water sorption increase significantly but with the limit of ADA specification. Conclusion:Within the limit of this study it can be concluded that the reinforcement with polypropylene fibers effective method to increase fracture resistance of denture base; while reinforcement with oxygen plasma treated polypropylene fibers further increase fracture resistance.
In this study, the effect of Nd: YAG laser on the activity of superoxide dismutase (SOD) and alcoholdehydrogenase (ADH) was investigated. The Saccharomyces cells were irradiated using 532nm Q-Switched Nd: YAG laser with (1Hz) frequency. Different fluences 11.3, 22.6 and 33.9mJ/cm2 and different number of pulses 15, 30 and 60 pulse were used. The irradiated cells were incubated in a liquid nutritive medium for 24 hours. After incubation, the cells were harvested and disrupted to extract the intracellular enzymes and their activities were assessed. In comparison with the control, the irradiated cells showed a significant increase in the activity and the specific activity of SOD at energy densities of 11.3 and 22.6mJ/cm2 at 30 and 60 pulses
... Show MoreFor the purpose of determining the impact of three levels of nitrogen fertilizer (0, 60, and 120 kg.ha-1) and sulfur fertilizer (0, 40, and 60 kg.ha-1) on production and growth indicators (number of leaves, number of branches, chlorophyll pigments, and fresh and dry weights), a field experiment was carried out during the winter season (2021/2022) in the fields of Al-Diwaniyah Province, Ministry of Agriculture, Diwaniyah Agriculture Directorate, Al-Nouriyah Forest Division. Means were compared using the least significant difference test (LSD) at a 0.05 level of probability. In a factorial experiment employing a wholly randomized block design wi
The main objective of this paper is to find the order and its exponent, the general form of all conjugacy classes, Artin characters table and Artin exponent for the group of lower unitriangular matrices L(3,? p ), where p is prime number.
A free convective heat transfer from the inside surface of a uniformly heated vertical circular tube has been experimentally investigated under a constant wall heat flux boundary condition for laminar air flow in the ranges of RaL from 6.9108 to 5109. The effect of the different sections (restrictions) lengths placed at the exit of the heated tube on the surface temperature distribution, the local and average heat transfer coefficients were examined. The experimental apparatus consists of aluminum circular tube with 900 mm length and 30 mm inside diameter (L/D=30). The exit sections (restrictions) were included circular tubes having the same inside diameter as the heated tube but with different lengths of
... Show MoreThe development taking place in various sports in performance, which was and still takes a large part by focusing on the specialized level of the players, whether in training or competition in all sports, including handball. In the competition (the match) by measuring the hormone beta-endorphin as well as. To identify the changes that occur in some biochemical variables as a result of the high effort in the competition (the match) by measuring lactic acid and the hormone aldosterone). The researcher used the descriptive method, the pre and post test of one group Due to the nature of the research, the research community was represented by Al-Shorta Sports players and Al-Jaish club players in handball, as they numbered (24) players from the t
... Show MoreThis study was aimed to determine the impact of Conocarpus erectus L. compost fertilizer, and some micronutrients on growth and production of potato. This research was conducted at one of the fields of the College of Agricultural Engineering Sciences - University of Baghdad. The experiment was implemented using factorial arrangement (4X3X3) within randomized complete block design with three replicates. Conocarpus fertilizer was represented the first factor with three levels (7.5, 15, 30 ton.ha-1), which symbolized (C2, C3, C4). Chemical fertilizer as recommended dose as a control, which symbolized (C1). The second factor was foliar spraying with three levels of iron (0, 100, 200 mg.L-1), which symbolized (F0, F1, F2). The third fact
... Show MoreKey-frame selection plays an important role in facial expression recognition systems. It helps in selecting the most representative frames that capture the different poses of the face. The effect of the number of selected keyframes has been studied in this paper to find its impact on the final accuracy of the emotion recognition system. Dynamic and static information is employed to select the most effective key-frames of the facial video with a short response time. Firstly, the absolute difference between the successive frames is used to reduce the number of frames and select the candidate ones which then contribute to the clustering process. The static-based information of the reduced sets of frames is then given to the fuzzy C-Means algor
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