Poly methyl methacrylate PMMA polymer could be considered the main material that used mostly in the recent years in denture base fabrication. It commonly known by it is poor strength properties such as low impact strength. The aim of the present research was to enhance the performance of PMMA denture base through the addition of two kind of nanoparticles (nano particles that selected from artificial and natural sources). Nano -particles from both Al2O3 and crushed peanut Peel were used for comparing purposes.Various weight fraction used in this study for both kinds of the additive (1%, 2% and 3%). Moreover, in this work a study and evaluation in impact strength (I.S.) value were done before and after immersion. The new prepared nanocomposite in three different liquids (mineral water, natural lemon juice and Pepsi) immersed during three specific time (10, 20 and 30 min), all tests completed at room temperature. It was found that the impact strength value before immersion decreased gradually during reinforcement with both type of nanoparticles except when using 3% of Peanuts Peel nanoparticles. Also, it was found after immersion pure PMMA in the three different liquid that the value of I.S. decreased. When immersion the prepared sample inside mineral water, it was noted that using Al2O3 as reinforcement the determined value decrease with increasing the weight fraction different from the Peanuts Peel. The obtained results showed that immersion these samples in naturel lemon juice increased the value of impact strength gradually with the time. I.S. value decreased while immersion nanocomposite of Al2O3 with Pepsi, while an obvious increase was clear with nanocomposite of Peanuts Peel with the immersion time.
Empirical equations for estimating thickening time and compressive strength of bentonitic - class "G" cement slurries were derived as a function of water to cement ratio and apparent viscosity (for any ratios). How the presence of such an equations easily extract the thickening time and compressive strength values of the oil field saves time without reference to the untreated control laboratory tests such as pressurized consistometer for thickening time test and Hydraulic Cement Mortars including water bath ( 24 hours ) for compressive strength test those may have more than one day.
Nowadays nanoparticles are used in many fields of life all over the world, and there are numerous ways to obtain them: chemical, physical and biological processes. In recent times, the biological method for the synthesis of nanoparticles associated with using plant extract is widely spread. Optimal conditions for synthesis of silver nanoparticles using aqueous seeds extract of Myristica fragrance were highlighted in this research, such as type of plant extract, weight of extracted plant material, volume ratio of plant extract to AgNO3 and temperature of reaction. The study proved that the optimal status for AgNPs synthesis by using 10 g of M. fragrance seeds powder were added to 100 mL boiled distilled water, then homogenized and f
... Show MoreIn this work, the effect of preparing a composite of copper oxide nanoparticles with carbon on some of its optical properties was studied. The composite preparing process was carried out by exploding graphite electrodes in an aqueous suspension of copper oxide. The properties of the plasma which is formed during the explosion were studied using emission spectroscopy in order to determine the most important elements that are present in the media. The electron’s density and their energy, which is the main factor in the composite process, were determined. The particle properties were studied before and after the exploding process. The XRD showed an additional peak in the copper oxides pattern corresponding to the hexagonal graphite struct
... Show MoreAbstract: Under high-excitation irradiance conditions to induce fluorescence, the dependence of photobleaching of Coumarin 307 (C307) and acriflavine (ACF) laser dyes in liquid and solid phases have been studied. A cw LD laser source of 1 mW and 407 nm wavelength was used as an exciting source. For one hour exposure time, it was found that the solid dye samples suffer photobleaching more than the liquid dye samples. This is because in liquid solutions the dye molecules can circulate during the irradiation, while the photobleaching is a serious problem when the dye is incorporated into solid matrix and cannot circulate.
this research aims to identify the impact of teaching with ana logies in collection of chemistry students grade average.And direction in order to verify to the zero hypothesis has been formulated and validated,The researcher conducted experiment lasted a full semester as experimental design was chosen (exactly)two equal one pilot and another officer.The research community has been selected one of intentional Middle School of the Education Directorate in B aghdad Karkh second either search sample consisted of (68) students from second grade average (34 ) Students for each group randomly selected research groups was equal to the following variables (lifetime months,parent of first grade chemistry degrees average test informat
... Show Moreتسعى تركيا ضمن سياساتها المائية ومنذ زمن بعيد وبأصرار على تنفيذ المزيد من بناء السدود والمشاريع التخزينية المائية على حوضي دجلة والفرات، الامر الذي يؤدي بالضرورة الى تناقص معدل الواردات المائية لنهري دجلة والفرات الداخلة للاراضي العراقية .وبالتالي التأثير على مقومات التنمية الزراعية العربية بشكل عام والتنمية الزراعية بالعراق بشكل خاص ومن ثم تهديد الامن الغذائي الوطني.
لذا فأن البحث يهد
... Show MoreRapid increase in the use of smart mobile phones and the proliferation of social media networking programs such as facebook, tweeter, whatsapp and viber etc. affects the learning attitude of second language. This research aims to investigate the effects of emoticons provided by Viber application on Iraqi students in context of vocabulary acquisition. 60 Iraqi students are randomly selected from X international school with the average of age 7 to 9 years. All the subjects are given 50 English words for five weeks, 25 English words were written on papers and the rest Viber stickers laden with English words. The results show that students recognize the vocabularies given by Viber stickers better than the written vocabulary. In general, student
... Show MoreAfrican-American writers during the 19th century wrote in the shadow of the prominent romance, sentimental, and domestic fiction. Harriet Wilson’s Our Nig (1859) reflects an “alternative social character”, for the female protagonist suffers racism in the free North, because she is a mulatto child. Through depicting the life of free blacks, who supposedly lives a better life than Southern slaves, Wilson exposes how she has actually lived and sensed life in antebellum America. According to Raymond Williams (2011), there are two kinds of literary writings. The first represents the general tendency of the age, and he calls it “dominant social character”; representing the majority content of both the public writing and speaking. But, a
... Show MoreThe study scrutinises intermingled relations between children literature and some ecological issues. Such interwoven relationships would be highly recommended to encourage children to explore and identify themselves with nature from early ages to avoid facing an extreme experience later on. The research limits its scope to two novels Suzanne Collins’ (1962) The Hunger Games trilogy (2003-2007) and William Golding’s (1911-1993) Lord of the Flies (1954), and both novels have no direct connections with Ecology and the Eco-consciousness, yet it offers an insightful description about Man’s experience with Nature. Moreover, it raises serious moral questions, raises awareness, heals wounds and suggests solutions for the problems th
... Show MoreArtificial intelligence (AI) is entering many fields of life nowadays. One of these fields is biometric authentication. Palm print recognition is considered a fundamental aspect of biometric identification systems due to the inherent stability, reliability, and uniqueness of palm print features, coupled with their non-invasive nature. In this paper, we develop an approach to identify individuals from palm print image recognition using Orange software in which a hybrid of AI methods: Deep Learning (DL) and traditional Machine Learning (ML) methods are used to enhance the overall performance metrics. The system comprises of three stages: pre-processing, feature extraction, and feature classification or matching. The SqueezeNet deep le
... Show More