Background: Dental implant considers a unique treatment option for the replacement of missing dentition. The new trend of implants is looking for materials which accelerate bone formation in bone implant interface and enhance osseointegration to provide immediate loading directly after placement and decrease the time period which is disturbs patients and uncomfortable. The aim of the study was to evaluate the effect of nano zirconium oxide (ZrO2) and nano hydroxyapatite (Hap) mixture coating of screw shaped commercially pure titanium (cpTi) implants on bond strength at the bone implant interface with torque removal test and histological analysis in comparison with non coated implants. Materials and methods: Forty screws were machined from cpTi rods using a lathe machine. Then 20 screws coated by electrophoretic deposition method by a mixture of nano hydroxyl apatite and nano zirconium oxide, while the other 20 screws remain uncoated. The tibia of 10 adult white New Zealand experimental rabbits was chosen as implantation site, each rabbit tibia received 2 screws, one coated and the other uncoated. Torque removal test was performed to measure the torque required to remove the screw and histological analysis was performed to observe the new bone formation, after 2 and 4 weeks healing intervals. Results: Implant coated with a mixture of nano zirconium oxide and nano hydroxyl apatite showed a significantly higher removal torque values compared to uncoated one. There was more new bone formation with coated implants for both healing periods. Conclusions: Coating by electrophoresis considers a valuable process to coat metallic implants with a ceramic material and to form a uniform composite layer of coating. Osseointegration improved at bone-implant interface associated with the coated implants, which was illustrated by higher bone formation at the two intervals of time 2 weeks and 4 weeks.
The present study focused mainly on the vibration analysis of composite laminated plates subjected to
thermal and mechanical loads or without any load (free vibration). Natural frequency and dynamic
response are analyzed by analytical, numerical and experimental analysis (by using impact hammer) for
different cases. The experimental investigation is to manufacture the laminates and to find mechanical
and thermal properties of glass-polyester such as longitudinal, transverse young modulus, shear modulus,
longitudinal and transverse thermal expansion and thermal conductivity. The vibration test carried to
find the three natural frequencies of plate. The design parameters of the laminates such as aspect ratio,
thickness
The main objective of this research is to design and select a composite plate to be used in fabricating wing skins of light unman air vehicle (UAV). The mechanical properties, weight and cost are the basis criteria of this selection. The fiber volume fraction, fillers and type of fiber with three levels for each were considered to optimize the composite plate selection. Finite element method was used to investigate the stress distribution on the wing at cruise flight condition in addition to estimate the maximum stress. An experiments plan has been designed to get the data on the basis of Taguchi technique. The most effective parameters at the process to be find out by employing L9
... Show MoreIn this study, the zinc oxide NPs have been synthesized from the fresh pomegranate peels extract using the precipitation method. The ZnO nanoparticles were produced from the reaction of fresh peels extract with zinc acetate salt which was used as zinc source in the presence of 2 M NaOH. The green synthesized nanoparticles were characterized through X-ray diffraction (XRD), UV-Vis diffuse reflection spectroscopy, Fourier transform infrared spectroscopy (FTIR), and Atomic force microscopy (AFM). The XRD patterns confirm the formation of hexagonal wurtzite phase structure for ZnO synthesized using pomegranate peels extract with average crystalline size of 28 nm. FTIR spectra identify the presence of many active functional groups for the pom
... Show MoreSmoking-related diseases can be attributed to the inhalation of many different toxins, including heavy metals, which have a host of harmful health effects. The primary objective of this study was to determine whether local and imported cigarette brands used in Iraq , have they elevated levels of metals or not .Three metals Lead (Pb) , Cadmium (Cd) and Chromium(Cr) were determined in tobacco of seventeen brands of imported cigarettes commonly available in Iraq and three Iraqi domestic cigarettes , which were randomly taken from retail market in Baghdad by using flame atomic absorption spectrometry. The produced data of imported and local cigarette brands were discussed and compared together and with studies from elsewhere .The result
... Show MoreCu (In, Ga) Se2 (CIGS) nano ink were synthesized from molecular precursors of CuCl, In Cl3, GaCl3 and Se metal heated to 240 °C for 1 hour in N2-atmosphere to form CIGS nanocrystal ink, Thin films were deposited onto Au/soda-lime glass (SLG) substrates. This work focused on CIGS nanocrystals, including their synthesis and application as the active light absorber layer in photovoltaic devices (PVs). This approach, using spin-coating deposition of the CIGS light absorber layers (75 mg/ml and 150 nm thickness), without high temperature selenization, has enabled up to 1.398 % power conversion efficiency under AM 1.5 solar illumination. X-ray diffraction (XRD) studies show that the structural formation of CIGS chalcopyrite structure. The mo
... Show MoreThis new azo dye 3-((2-(1H-indol-3-yl) ethyl) diazenyl) quinoline-2-ol was subsequently used to prepare a series of complexes with the metal ions of Cr+3, Cu+2, VO+2, Mn+2and Mo+6. The compounds identified by 1H and 13C-NMR, FT-IR, UV-Vis, mass spectroscopy, as well as TGA, DSC, and C.H.N., conductivity, magnetic susceptibility, metal and chlorine content. The results showed that the ligand behaves in a bidantate, and that the complexes gave octahedral, excepting for VO+2 square pyramid was given, that all complexes are non-electrolytes. The effectiveness of mention the compounds in inhibiting free radicals was evaluated by the ability to act as an antioxidant was measured using DPPH as a free radical and gallic acid as a standard s
... Show MoreThe liver is one of the most prominent glands in the digestive system. It crosses vital organs with multiple functions, including the secretion of enzymes, digestion of fats, and secretion of bile. Through histological studies and those interested in them, the tissue structure of the liver is of interest to researchers, and the four samples of Guinea pig Cavia porcellus were taken in this study to know the histological structure and compare it with rodents in particular. and other animals in general. The results of the liver parenchyma were comparable to those of the studied mammals in periods of hepatocytes, Kupffer cells, and sinusoids surrounding the central vein, blood supply, and bile ducts. He did not record differences, eve
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