The primary purpose of the present research was to study the effect of polyvinyl chloride (PVC) powder content on ultrasonic wave velocity in PVC/Epoxy composites. The second part is concerned with the relations of dynamic elastic moduli with the ultrasonic wave velocities, to determine how ultrasonic waves can affect them.
Experimental data have been obtained using the sonic viewer (model -5217 A) device to generate two types of waves, longitudinal waves of frequency 63 kHz and transverse waves of frequency 33 kHz and to measure the transit time required for those waves to travel through individual sample.
The experimental results have shown that the propagation of the ultrasonic velocity increases directly with PVC content in the
This research is addressing the effect of different ferrocene concentration (0.00, 2.15x10-3, 4.30x10-3, 8.60x10-3, and 12.9x10-3) on the bulk free radical polymerization of methyl methacrylate monomer in benzene using benzoyl peroxide as initiator. The polymerization was conducted at 60º C under free oxygen atmosphere. The resulting polymers were characterized by FTIR. The results were compared with the presence and absence of ferrocene at 10% conversion. The %conversion was 3.04% with no ferrocene present in the polymerization medium and its increase to 9.06 with a first lowest ferrocene concentration added, i.e. 2.15 x10-3mol/l. This was positively reflected on the poly(methyl methacrylate) molecular weight measured by viscosity techniq
... Show MoreAbstract: Coriandrum sativum leaves are used in folk medicine to treat several diseases such as digestive system disorder, diabetes, and hyperlipidemia. This study was designed to investigate the effect of aqueous extract of Coriandrum sativum on the structure and function of kidney, 30 males of white Swiss mice Mus musculus were divided randomly to three groups with 10 mice in each group. Animals of first group (control group) had been given orally 0.1 ml of tap water, animals in the second group had been treated orally with 0.1 of single dose (125 mg/Kg b. w./day) of C. sativum leaves extract and animals in the third group has been treated orally with 0.1 ml (250mg/Kg. b. w./day) of the same extract for 30 days. At the end of experiment,
... Show MoreBackground: Ageing is a continuous accumulative ordinary physiological phenomena occurs upon all organs and body structures including saliva by its constituents which can influence the caries process, for that this study was conducted to determine the impact of ageing on selected chemical composition of saliva and their effects on dental caries experience characteristics at different age groups among apparently healthy men. Materials and method: A descriptive comparative study was conducted to compare between three study samples (young, middle and old age adults), thirty male in each study insert, aged (20 years, 40 years and 60 years) respectively. They were selected from private health center in Baghdad - Iraq, from the mid of November
... Show MoreAbstract : Tin oxide SnO2 films were prepared by atmospheric chemical vapor deposition (APCVD) technique. Our study focus on prepare SnO2 films by using capillary tube as deposition nozzle and the effect of these tubes on the structural properties and optical properties of the prepared samples. X-ray diffraction (XRD) was employed to find the crystallite size. (XRD) studies show that the structure of a thin films changes from polycrystalline to amorphous by increasing the number of capillary tubes used in sample preparation. Maximum transmission can be measured is (95%) at three capillary tube. (AFM) where use to analyze the morphology of the tin oxides surface. Roughness and average grain size for different number of capillary tubes have b
... Show MoreStereo lithography (SLA) three-dimensional (3D) printing process is a type of additive manufacturing techniques that uses digital models from computer-aided design to automatically produce customized 3D objects. Around 30 years, it has been widely utilized in the manufacturing, design, engineering, industrial sectors and its applications in dentistry for manufacturing prosthodontics are very important. The stereo lithography technology is highly regarded because it can produce items with excellent precision especially when selecting the best process parameters. This review article offers a useful and scientific summary of SLA three-dimensional printing technology and its brief history. The specific type of 3D printers which is SLA t
... Show MoreIn this study, the effect of the combination of micro steel fibers and additives (calcium hydroxide and sodium carbonate) on the size of cracks formation and healing them were investigated. This study aims to apply the use of self-healing phenomenon to repair cracks and to enhance the service life of the concrete structures. Micro steel fibers straight type were used in this research with 0.2% and 0.4% by volume of concrete. A weight of 20 and 30 kg/m3 of Ca(OH)2 and 2 and 3 kg/m3 of Na2CO3 were used as a partial cement replacement. The results confirm that the concrete cracks were significantly self-healed up to 30 days re-curing. Cracks width up to 0.2 mm were comp
... Show MoreFast-dissolving films are one of the interested delivery systems for oral solid dosage forms to overcome swallowing difficulty for geriatric and pediatric patients. Zafirlukast (ZLK) is one of the most commonly used oral medication for treatment of asthmatic patients particularly mild to moderate cases. Oral fast dissolving films of ZLK were prepared using two different filming forming polymers, hydroxypropyl methylcellulose (HPMC) and sodium carboxymethyl cellulose (SCMC). Different concentrations of the 2 polymers were used to prepare 10 formulas. Other excipients were also added at various ratios to produce 10 different formulations. These were maltodextrin, crosspivodone, polyvinylpyrrolidone (PVP), and banana powder. In vitro c
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