In this research, hand lay- up technique is used to prepare samples from epoxy resin reinforced with multi- walled carbon nanotubes in different weight fractions (0, 2, 3, 4, 5) wt%. The immersion effect by sodium hydroxide solution (NaOH) at normality (0.3N) for a period of (15 days) on the thermal conductivity of nanocomposites was studied, and compared to natural condition (before immersion). The thermal conductivity of epoxy nanocomposites specimens were carried out using Lee’s disk method. The experimental results showed that thermal conductivity increased with increase weight fraction before and after immersion for all specimens, while the immersion effect leads to decrease thermal conductive values compared to thermal conductivity values in natural condition.
School administration has an effective role in stimulating academic achievement, as it is the ideal regulation and activation of material and human power to achieve the goals of the educational process. This role has axes in the form of interests, aids, and specific procedures exercised by the school administration in improving the educational process, and assisting researchers in achieving the highest levels of academic achievement. This activation is achieved through stages of planning, organizing, coordinating, and evaluating.
To achieve the aims of this research, the researcher pursued the descriptive analytical approach, which is considered one of the most appropriate approaches to the nature of this type of research. The qu
... Show MoreThis research aims to knowledge the extent of the application of Tuz General Hospital to the concept of tacit knowledge dimensions (mental models, intuition, experience, skill) and methods of acquiring knowledge dimensions (training, job rotation, work teams) and the measurement and analysis of the link and the kind of impact between the methods of acquiring knowledge and tacit knowledge of the Angels nursing in the researched hospital, and was the questionnaire primary means of collecting information adopted by the researcher that, the research sample of (90) individuals, including the Angels nursing, has been using the statistical program spss for the purpose of conducting statistical treatments, and through the diagnosis and m
... Show MoreBackground: The Streptococcus genus are the predominant bacteria in the mouth and the Streptococcus sanguinis is one of them which performing a primary function for expansion of dental biofilm. Gingival and periodontal disorders are caused by dental biofilm, today, there is a necessity to discover naturally presenting antibacterial compounds from herbs with less side effects as a substitutive to the commonly handled chlorohexidine. Thus, the purpose of this study was to assess the antibacterial activity of thymus vulgaris oil on Streptococcus sanguinis bacteria In vitro. Materials and Methods: Human supragingival plaque samples were taken from 10 subjects, then morphological and microscopical examination, bioch
... Show MoreDam 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 MoreThis research investigates the type and the significant relationship between roaming management and self-efficacy and its impact on excellence in providing hotel service. To achieve this, the applied approach was adopted through A questionnaire was designed and developed for the collected data. It has consisted of three parts. The firsts section included nine questions to measure the dimensions of management by roaming. The second section includes nine questions to measure the effectiveness of the two employees. The last section includes 12 questions to measure the excellence of the hotel service. The research sample included 43 employees' responding to this
... Show MoreCarrageenan extract is a compound of sulfated polyglycan that is taken out from red seaweeds. Being hydrocolloid in nature, carrageenan has gelling, emulsifying and thickening properties allowing it to be commonly used in the oral healthcare products and cosmetics. Due to its bioactive compounds, carrageenan has been shown to have antimicrobial, antiviral, and antitumor properties. The purpose of this work is to study the probable use of carrageenan on the diseases that are related to oral cavity and on the genomic DNA in in vitro experimental model
In this study, the effects of k-carrageenan on four different cell lines related to the cancer and normal cells which cultured on selective media were done. Moreover, the eff
... Show MoreBackground: The use of Miswak, chewing sticks (salvadorapersica) can be traced back to Babylonians some 7000 years ago. It is commonly used throughout the world especially for the purpose of oral hygiene. Muslims are using as the religious view. Current study aimed to test the ability of aqueous siwak extract to increase the resistance of enamel surface against acid dissolution compared to sodium fluoride. Materials and Method: Twenty maxillary first premolars were treated with the selected solutions included two aqueous siwak extract concentration(5%,10%) and sodium fluoride(0.05%)as control positive for 2 minutes once daily for 20days interval, de ionized water was used as control negative. The concentration of the dissolved phosphorus i
... Show Moreunacceptable social behaviors, particularly withdrawal behavior that appears in children with autism represent a major problem hindering the process of communication with those around them and therefore the process of mergence with them be difficult.
The withdrawal causes a real affect deficit for children with autism limits the possibility of development of their intellectual and mental growth due to their solitude and the weakness of their focus in the acquisition of pedagogical skills and lack the necessary social skills to maintain the relations of friendship and enjoyment of them.
withdrawal children fail to participate
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