In the present research the flame retardancy to buildings and industrial foundations which are manufacturing from advanced polymeric composite material was increased by coating it with surface layer included flame retardant material. A(3mm) thick antimony tetroxide was used as a coated layer to retard and prevent the flame spread to the coating surface of polyester resin (SIROPOL 8340-PI) reinforced with hybrid fibers as a woven roving (°45-°0) consist of carbon and kevlar (49) fibers, and exposed it to direct flame generated from gas torch at temperature of (2000ºC), at different exposed distance (10,15,20mm)and study the rang of resistance for this layer and its ability to protect the under composite material . The result obtained from erosion test show an improvement to the resistance of the composite material to high temperature after addition of antimony tetroxide layer and this resistance increased with increasing the exposed distance of flame .
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Water quality sensors have recently received a lot of attention due to their impact on human health. Due to their distinct features, environmental sensors are based on carbon quantum dots (CQDs). In this study, CQDs were prepared using the electro-chemical method, where the structural and optical properties were studied. These quantum dots were used in the environmental sensor application after mixing them with three different materials: CQDs, Alq3 polymer and CQDs and Alq3 solutions using two different methods: drop casting and spin coating, and depositing them on silicon. The sensitivity of the water pollutants was studied for each case of the prepared samples after measuring the change in resistance of the samples at a temperature of
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In this paper, the problem of resource allocation at Al-Raji Company for soft drinks and juices was studied. The company produces several types of tasks to produce juices and soft drinks, which need machines to accomplish these tasks, as it has 6 machines that want to allocate to 4 different tasks to accomplish these tasks. The machines assigned to each task are subject to failure, as these machines are repaired to participate again in the production process. From past records of the company, the probability of failure machines at each task was calculated depending on company data information. Also, the time required for each machine to complete each task was recorded. The aim of this paper is to determine the minimum expected ti
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Background: 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 MoreCarbon Nanopowder was fabricated by arc discharge technique at deposition pressure of 10-5 mbar Argon gas on glass substrates. The prepared carbon nano- powder was collected from chamber and purified with nitric acid at 323K .The morphology and crystalline structure of the prepared powder was examined by X-Ray Diffraction (XRD), Atomic Force Microscope (AFM), and Scanning Electron Microscope (SEM). XRD spectrums showed that the powder exhibits amorphous structure and after purification, the powder showed hexagonal structure with a preferential orientation along(002) direction ,where AFM and SEM gave very compatible estimation on the grain size and shape of the nanopowder.
INFLUENCE OF SOME FACTOR ON SOMATIC EMBRYOS INDUCTION AND GERMINATION OF DATE PALM BARHI C.V BY USING CELL SUSPENSION CULTURE TECHNIQUE
The effective surface area of drug particle is increased by a reduction in the particle size. Since dissolution takes place at the surface of the solute, the larger the surface area, the further rapid is the rate of drug dissolution. Ketoprofen is class II type drug according to (Biopharmaceutics Classification System BCS) with low solubility and high permeability. The aim of this investigation was to increase the solubility and hence the dissolution rate by the preparation of ketoprofen nanosuspension using solvent evaporation method. Materials like PVP K30, poloxamer 188, HPMC E5, HPMC E15, HPMC E50, Tween 80 were used as stabilizers in perpetration of differ
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