Commercially pure titanium (cpTi) is widely used as dental implant material although it was found that titanium exhibited high modulus of elasticity and the lower corrosion tendency in oral environment. Niobium(Nb) was chosen for this study as an alternative to cpTi implant material due to its bioinert behavior and good elastic modulus and moderate cost in addition to corrosion resistance. This study was done to evaluate the effect of biomimetic coating on the surface properties of the commercially pure titanium and niobium implants by in vitro and in vivo experiments. The in vitro study was involved etching the samples of each material in HCl then soaking in 10M NaOH aqueous solution. These samples were then immersed in a 5 times concentrated simulated body fluid for 14 days. Scanning Electron Microscope, Energy Dispersive X-ray, and X-Ray Diffraction tests were done to analyze surface changes. The in vivo study was done by the implantation of screw-shaped implants (two from each material, uncoated and the other was biomimetically coated) in the tibias of New Zealand rabbits. After 2 and 4 weeks of healing period, 20 rabbits were sacrificed for each period. A removal torque was done for ten animals in each group, whereas the other ten were used for histological testing and histomorphometric analysis with optical microscope.The in vitro experiments showed that the use of 14 days immersion in a concentrated simulated body fluid produced a layer of calcium phosphate on metal surfaces. The removal torque values and new bone formation were increased significantly in Nb than Ti, in coated than uncoated screws, and in 4 weeks than 2 weeks healing periods. The Nb implants had better biomechanical and biological properties than the commercially pure titanium implants and can be used as an alternative dental implant.
Multi-drug-resistant uropathogenic Escherichia coli (UPEC) is considered a significant challenge due to its ability to resist antibiotics and form biofilms. UPEC biofilm formers are well protected and largely inaccessible to antibiotics, which leads to persistent infections and evasion of the host immune system. Understanding how ciprofloxacin and trimethoprim/sulfamethoxazole affect biofilm formation is essential for improving treatment strategies for urinary tract infections (UTIs). A total of 76 UPEC isolates were obtained from Iraqi patients and identified using morphological and biochemical characteristics, as well as the Vitek®-2 Compact system. Minimum inhibitory concentrations (MICs) were determined using the Vitek®-2 system, whic
... Show MoreAlxSb1-x compounds with different aluminum content(x=0.1, 0.3 , 0.5 , 0.7 and 0.9 ) were prepared by mixing the two elements in the appropriate ratios in quartz ampulla which then sealed and put in an oven at 1273 and left 5 hours. The obtained powder were grinded and then pressed in pellets shape which will be the target to prepare thin films samples. AlxSb1-x thin films were synthesized by PLD with ~ 150nm in thickness .The structures of AlxSb1-x powders and thin films were determined using X–ray diffraction. The data revealed that all the prepare AlxSb1-x bulk and thin films have polycrystalline . The results showed that increasing of Al reduced the crystallinity of the prepared samples at the first but then the opposite take pla
... Show MoreAlO-doped ZnO nanocrystalline thin films from with nano crystallite size in the range (19-15 nm) were fabricated by pulsed laser deposition technique. The reduction of crystallite size by increasing of doping ratio shift the bandgap to IR region the optical band gap decreases in a consistent manner, from 3.21to 2.1 eV by increasing AlO doping ratio from 0 to 7wt% but then returns to grow up to 3.21 eV by a further increase the doping ratio. The bandgap increment obtained for 9% AlO dopant concentration can be clarified in terms of the Burstein–Moss effect whereas the aluminum donor atom increased the carrier's concentration which in turn shifts the Fermi level and widened the bandgap (blue-shift). The engineering of the bandgap by
... Show MoreCompounds from ZnO doped with AgO in different ratio (0,3,5,7, and 9)wt.% were prepared.Thin films from the prepared compounds were deposited on a glass substrate using the pulsed laser deposition method. The XRD pattern confirmed the presence of a single-phase hexagonal wurtzite ZnO structure, without the presence of a secondary phase. AFM measurements showed an increase in both average grain size and average surface roughness with increasing concentration content of (AgO).The crystallite size of ZnO of the main peak corresponding to the preferred plane of crystal growth named (100) increases from 17.8 to 22.5nm by increasing of AgO doping ratio from 0 to 9%. The absorbance and transmittance in the wavelength range (350-1100 nm)
... Show MoreThe aim of this investigation is to evaluate the experimental and numerical effectiveness of a new kind of composite column by using Glass Fiber‐Reinforced Polymer (GFRP) I‐section as well as steel I‐section in comparison to the typical reinforced concrete one. The experimental part included testing six composite columns categorized into two groups according to the slenderness ratio and tested under concentric axial load. Each group contains three specimens with the same dimensions and length, while different cross‐section configurations were used. Columns with reinforced concrete cross‐section (reference column), encased GFRP I‐section, and encased steel I‐section were adopted in each
The current research discusses “The impact of the critical factors for the transfer of knowledge on opportunities and strategic success ", the attention have been increased on knowledge transfer and strategic success subjects because on being one of the important and contemporary issues, which have a significant impact on the existence of organizations and its future. The research aims to identify the critical factors for knowledge transfer in private high education environment which enables (the college community surveyed) to achieve strategic success, also the research sought to answer questions related to research problem by testing a number of major and minor hypothes in impact, in order to test the hypotheses I used a fiel
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Background Green synthesis of silver nanoparticles (AgNPs) using plant extracts has gained increasing attention as an environmentally friendly alternative to conventional chemical methods.
يختبر البحث الحالي التأثيرات المشتركة للإشعاع بالموجات فوق الصوتية والمادة المانحة للهيدروجين على لزوجة النفط الخام الثقيل. تمت دراسة تأثير زمن التعرض للموجات فوق الصوتية والطاقة ودورة التشغيل ودرجة الحرارة على لزوجة النفط الخام العراقي الثقيل الذي يملك قيمة .20.32 = API كما تم فحص لزوجة عينات النفط الخام التي تم خلطها بمانح الهيدروجين (Decalin) وإخضاعها للمعالجة بالموجات فوق الصوتية في ظل الظروف المثا
... Show Moreتتضمن إزالة الكبريت إزالة مركبات الكبريت العضوية من زيوت الوقود. في هذه الدراسة، تم استخدام تقنية البلازما اللاحرارية وتقنية البلازما بمساعدة بيروكسيد الهيدروجين لاكسدة الوقود المحتوي على مركبات من benzothiophene و dibenzothiophene. تم إجراء تفاعل الأكسدة باستخدام منظومة dielectric barrier discharge لتوليد بلازما غير حرارية. النتائج أظهرت ان تقنية البلازما ومزيج من البلازما مع بيروكسيد الهيدروجين معًا لأكسدة BT و DBT. تتبعان pseudo-
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