Background: to evaluate the effect of different dentifrices on the surface roughness of two composite resins (nanofilled-based and nanoceramic – based composite resins). Materials and methods: Forty specimens (diameter 12 mm and height of 2mm) prepared from different composite resin materials: Z350 (nanofilled composite, and Ceram-X (nanoceramic) .they were subjected to brushing simulation equivalent to the period of 1 year. The groups assessed were a control group brushed with distilled water (G1), Opalescence whitening toothpasteR (G2), Colgate sensitive pro-relief (G3) and Biomed Charcoal Toothpaste (G4). The initial and final roughness of each group was tested by surface roughness tester. The results were statistically analyzed using
... Show MoreAbstract: This study aims to investigate the backscattering electron coefficient for SixGe1-x/Si heterostructure sample as a function of primary electron beam energy (0.25-20 keV) and Ge concentration in the alloy. The results obtained have several characteristics that are as follows: the first one is that the intensity of the backscattered signal above the alloy is mainly related to the average atomic number of the SixGe1-x alloy. The second feature is that the backscattering electron coefficient line scan shows a constant value above each layer at low primary electron energies below 5 keV. However, at 5 keV and above, a peak and a dip appeared on the line scan above Si-Ge alloy and Si, respectively, close to the interfacing line
... Show MoreIn this research, we studied the effect of concentration carriers on the efficiency of the N749-TiO2 heterogeneous solar cell based on quantum electron transfer theory using a donor-acceptor scenario. The photoelectric properties of the N749-TiO2 interfaces in dye sensitized solar cells DSSCs are calculated using the J-V curves. For the (CH3)3COH solvent, the N749-TiO2 heterogeneous solar cell shows that the concentration carrier together with the strength coupling are the main factors affecting the current density, fill factor and efficiency. The current density and current increase as the concentration increases and the
The aim of this study was to know the inhibition activity of squeezed grape waste extract on Bacillus stearpthermophilus by using three different tempretures degree 40, 60 and 80c, in order to reduce the time exposure of food for preservation. This study include two branchs: First: isolation and identification of Bacillus stearothermophilus from soil, 5 sample were collected from the soil of the college agriculture/Baghdad university. Samples were cultured on nutrient agar, microscopic and culturing tests were conducted and many biochemical tests were done. The isolates were cultivated at 55 c and 65 c for differentiate it from Bacillus coagulans which is can't grow at 65 co. The c
... Show MoreHands have consistently been an important vehicle in the transmission of disease (1). Thus, thorough hand-washing remains the single most important factor in preventing infection specially in hospitals and labs.Twenty-nine non-clinical volunteers (do not work or come in contact with a clinical or hospital setting) that lacked visible skin injuries, eczema or apparent skin disease were used, those subjects were all tested by a material of each of the three used in the study weekly and laboratory tests were done pre- and post washing.All three material were effective , Eugenol extract as effective as the bar and lotion soap. And this was confirmed statistically.Eugenol has a great antibacterial action even in small concentration and t
... Show MoreIn this research prepare membranes pure silicon carbide (SiC) as well as gas Alloy (ammonia) and using a laser was leaked membrane of glass flooring. To Drasesh optical properties of membranes prepared depending on the technique (Swanepoel) and Adhrt results obtained in general increased permeability pure silicon membranes
The synthesis of new substituted cobalt Phthalocyanine (CoPc) was carried out using starting materials Naphthalene-1,4,5, tetracarbonic acid dianhydride (NDI) employing dry process method. Metal oxides (MO) alloy of (60%Ni3O4 40%-Co3O4 ) have been functionalized with multiwall carbon nanotubes (F-MWCNTs) to produce (F-MWCNTs/MO) nanocomposite (E2) and mixed with CoPc to yield (F-MWCNT/CoPc/MO) (E3). These composites were investigated using different analytical and spectrophotometric methods such as 1H-NMR (0-18 ppm), FTIR spectroscopy in the range of (400-4000cm-1), powder X-rays diffraction (PXRD, 2θ o = 10-80), Raman spectroscopy (0-4000 cm-1), and UV-Visib
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Knowing the amount of residual stresses and find technological solutions to minimize and control them during the production operation are an important task because great levels of deformation which occurs in single point incremental forming (SPIF), this induce highly non-uniform residual stresses. In this papera propose of a method for multilayer single point incremental forming with change in thickness of the top plate (0.5, 0.7, 0.9) mm and lubrication or material between two plates(polymer, grease, grease with graphite, mos2) to knowing an effect of this method and parameters on residual stresses for the bottom plates. Also compare these results for the
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