In this work, spinel ferrites (NiCoFe2O4) were prepared as thin films by dc reactive dual-magnetron co-sputtering technique. Effects of some operation parameters, such as inter-electrode distance, and preparation conditions such as mixing ratio of argon and oxygen in the gas mixture, on the structural and spectroscopic characteristics of the prepared samples were studied. For samples prepared at inter-electrode distance of 5 cm, only one functional group of OH- was observed in the FTIR spectra as all bands belonging to the metal-oxygen vibration were observed. Similarly, the XRD results showed that decreasing the pressure of oxygen in the gas mixture lead to grow more crystal planes in the samples prepared at inter-electrode distance of 5 cm. The energy band gap was determined for the sample prepared with mixing ratio of 65:35 and found to be 2.7, 2 and 3.35 eV for direct allowed, direct forbidden and indirect allowed transitions, respectively. The high structural purity was confirmed as no traces for any elements other than Co, Ni, Fe and O were found in the final samples.
Industrial buildings usually are designed to sustain several types of load systems, such as dead, live, and dynamic loads (especially the harmonic load produced by rotary motors). In general, these buildings require high-strength structural elements to carry the applied loads. Moreover, Reactive Powder Concrete (RPC) has been used for this purpose because of its excellent mechanical strength and endurance. Therefore, this study provides an experimental analysis of the structural behaviors of reinforced RPC beams under harmonic loads. The experimental program consisted of testing six simply supported RPC beams with lengths of 1500 mm, widths of 150 mm, and thicknesses of 200 mm under harmonic loading with varied frequencies between 1
... Show MoreSince decades silver was depended worldwide as a treatment to a lot of diseases
ranging from burn infections, anthrax, and typhoid fever to bacterial conjunctivitis
in stillbirth, but its effectiveness against biofilms is still undetermined. Salmonella is
a major cause of food poisoning outbreaks especially in the third world countries.
Thus, in the present study; the antimicrobial activity of silver nanoparticles (Ag-
NPs) against Salmonella enterica biofilm was examined; their activity was
compared with amino acid; D-Glycin and imipenem antibiotic. The result of the
study revealed that Ag-NPs exhibited considerable antimicrobial property against
Salmonella enterica biofilm where the minimum inhibitory concentrat
wind load coefficient
The Manganese (Mn) thin films of obliquely and normal deposited were prepared by using thermal evaporation method at pressure 10-5 torr on glass substrate at room temperature. The optical properties of normal and obliquely deposited films are studied and also the effect of deposition angle on these properties. The deposition angle has great influence on the increase of the absorbance, absorption coefficient, extinction coefficient and imaginary dielectric constant and the decrease of the transmittance, reflectance, refractive index and real dielectric constant.
Objective: Per-implantitis is one of the implant treatment complications. Dentists have failed to restore damaged periodontium by using conventional therapies. Tissue engineering (stem cells, scaffold and growth factors) aims to reconstruct natural tissues. The paper aimed to isolate both periodontal ligament stem cells (PDLSCs) and bone marrow mesenchymal stem cells (BMMSCs) and use them in a co-culture method to create three-layered cell sheets for reconstructing natural periodontal ligament (PDL) tissue. Materials and methods: BMMSCs were isolated from rabbit tibia and femur, and PDLSC culture was established from the lower right incisor. The cells were co-cultured to induce BMMSC differentiation into PDL cells. Cell morphology, stem cel
... Show MoreThe extraction, study, and accurate interpretation of the morphology database of a basin are the basic blocks for building a valid geomorphological understanding of this basin. In this work, a new approach is presented which is to use three different GIS based methods to extract databases with specific geographical information and then use the concept of information intersection to make a realistic geomorphological perspective for the study area.
In the first method, data integration of remote sensing images from Google Map and SRTM DEM images were used to identify Horan basin borders.
In the second method, the principle of data integration was represented by extracting the quantitative values of the morphometric c
... Show MoreIn this work, nanostructure zinc sulfide (ZnS) thin films at temperature of substrate 450 oC and thickness (120) nm have been produced by chemical spray pyrolysis method. The X-Ray Diffraction (XRD) measurements of the film showed that they have a polycrystalline structure and possessed a hexagonal phase with strong crystalline orientation of (103). The grain size was measured using scanning electron microscope (SEM) which was approximately equal to 80 nm. The linear optical measurements showed that ZnS nanostructure has direct energy gap. Nonlinear optical properties experiments were performed using Q-switched 532 nm Nd:YAG laser Z-scan system. The nonlinear refractive index (n2) and nonlinear absorption coefficient (β) estimated for Z
... Show MoreThis paper attempted to study the effect of cutting parameters (spindle speed and feed rate) on delamination phenomena during the drilling glass-polyester composites. Drilling process was done by CNC machine with 10 mm diameter of high-speed steel (HSS) drill bit. Taguchi technique with L16 orthogonal layout was used to analyze the effective parameters on delamination factor. The optimal experiment was no. 13 with spindle speed 1273 rpm and feed 0.05 mm/rev with minimum delamination factor 1.28. &
... Show MoreNatural dye sensitized solar cell was prepared using strawberry and pomegranate dyes with anatase nanocrystalline titanium dioxide powder. A study of the optical properties of the two dyes, involving the absorption spectrum was determined in the visible region. I-V characteristics under illumination were performed. The results showed that the two prepared dye sensitized solar cells have acceptable values efficiency about (0.94 with Fill factor (45)) and (0.74 with Fill factor (44)) for strawberry and pomegranate dyes, respectively.