Objectives This work presents laser coating of grade 1 pure titanium (Ti) dental implant surface with sintered biological apatite beta-tricalcium phosphate (β-TCP), which has a chemical composition close to bone. Materials and methods Pulsed Nd:YAG laser of single pulse capability up to 70 J/10 ms and pulse peak power of 8 kW was used to implement the task. Laser pulse peak power, pulse duration, repetition rate and scanning speed were modulated to achieve the most homogenous, cohesive and highly adherent coat layer. Scanning electron microscopy (SEM), energy dispersive X-ray microscopy (EDX), optical microscopy and nanoindentation analyses were conducted to characterise and evaluate the microstructure, phases, modulus of elasticity of the coating layer and calcium-to-phosphate ratio and composition. Results showed that the laser power and scanning speed influenced coating adherence. The cross-sectional field-emission scanning electron microscopy images at low power and high speed showed poor adherence and improved as the laser power increased to 2 kW. Decreasing the scanning speed to 0.2 mm/s at the same power of 2 kW increased adherence. EDX results of the substrate demonstrated that the chemical composition of the coat layer did not change after processing. Moreover, the maps revealed proper distribution of Ca and P with some agglomeration on the surface. The sharp peaks on the X-ray diffraction patterns indicated that β-TCPs in the coat layer were mostly crystalline. The elastic modulus was low at the surface and increased gradually with depth to reach 19 GPa at 200 nm; this value was close to that of bone. The microhardness of the coated substrate increased by about 88%. The laser pulse energy of 8.3 J, pulse peak power of 2 kW, pulse duration of 4.3 min, repetition rate of 10 Hz and scanning speed of 0.2 ms−1 yielded the best results. Conclusion: Both processing and coating have potential use for dental implant applications.
Playing is the only common language among children in every place and time, to the fact that what distinguishes the children is their quest to play and fun way innate, not acquired, which is expressed with the child really is one of the rights. And play a key entrance to the growth of the child mentally, intellectually and cognitively and not for the child emotionally and socially just. In the play the child begins to identify and classify objects and learn concepts and circulate among themselves on a linguistic basis. Activity here and play a major role in leading the linguistic development of the child in the composition has the communication skills.
The Games (especially intellectual ones) Whatever the cause of the development
... Show MoreIn this work, an investigation for the dynamic analysis of thin composite cylindrical and spherical shells is presented. The analytical solution is based upon the higher order shear deformation theory of elastic shells from which the developed equations are derived to deal with orthotropic layers. This will cover the determination of the fundamental natural frequencies and mode shapes for simply supported composites cylindrical and spherical shells.
The analytical results obtained by using the derived equations were confirmed by the finite element technique using the well known Ansys package. The results have shown a good agreement with a maximum percentage of discrepancy, which gives a confidence o
... Show MoreThe main purpose of this paper is to study feebly open and feebly closed mappings and we proved several results about that by using some concepts of topological feebly open and feebly closed sets , semi open (- closed ) set , gs-(sg-) closed set and composition of mappings.
Praise be to Allaah Mahmoud every tongue, the idol of all time, which is not without
his knowledge everywhere, not occupied like for like, most of all likes and peer, and picnic
for wife and children, and carried out his reign in all the subjects, neither representative by the
brains to think, nor fancy hearts photography, (is not nothing like Him, He is the All-Seer),
and prayer and peace be upon the Messengers Muhammad and his family and companions
and followed them in truth until the Day of Judgment.
After…..
Has spoken in this search for The inheritance of women before and after Islam
legislative provisions which, because of its importance to show the right of women's rights,
which began Msluba before Isl
Some new heterocyclic compounds containing, cyclohexenone, indazole, isoxazoline, pyrmidine and pyrazoline ring system were prepared from chalcones (1a,b). The starting chalcones (1a,b) were obtained by a base catalyzed condensation of appropriately substituted benzaldehydes and 2-acetylbenzofuran. The reaction of the prepared chalcones with ethylacetoacetate/hydrazine hydrate, hydroxylamine hydrochloride, urea, thiourea, hydrazine hydrate, phenyl hydrazine or hydrazide derivatives gave the mentioned heterocycles. All synthesized compounds have been characterized by physical and spectral methods.
This study included isolation and identification of the fungi associated with Aloe vera (L.) in nurseries and plant gardens. The results showed that the fungi Alternaria alternata, Fusarium oxysporum, Fusarium solani, Nigrospora oryzae, Cladosporium herbarum, Stemphylium botryosum, Aspergillus niger, Penicillium sp. were isolated from the diseased leaves of Aloe vera showing spots and blight symptoms. The percentages of disease incidence in March, Jun and August were found to be 5, 50 and 60 %, respectively. Pathogenicity test of Alternaria alternata, Fusarium oxysporum, Nigrospora oryzae and Cladosporium herbarum showed that disease index were 50, 25,25and 12.5 %,
... Show MoreBackground: Moringa peregrina is widely used in the traditional medicine of the Arabian Peninsula to treat various ailments, because it has many pharmacologically active components with several therapeutic effects. Objective: This study aimed to investigate the inhibitory effect of Moringa peregrina seed ethanolic extract (MPSE) against key enzymes involved in human pathologies, such as angiogenesis (thymidine phosphorylase), diabetes (α-glucosidase), and idiopathic intracranial hypertension (carbonic anhydrase). In addition, the anticancer properties were tested against the SH-SY5Y(human neuroblastoma). Results: MPSE extract significantly inhibited α-glucosidase, thymidine phosphorylase, and carbonic anhydrase with half-maximal i
... Show MoreObjective: Since the vaccination rate is largely affected by low knowledge and negative attitudes ofhealthcare professionals, so this study aimed to weigh up the vaccination knowledge and attitudes ofpharmacy students.Method: A pilot study using a survey to investigate demographic data, knowledge (20 questions), andattitudes (5 questions) of 156 fifth year and 121 third year pharmacy students from College of Pharmacy/University of Baghdad.Results: The mean score of knowledge and attitudes was intermediate (16.654 and 14.917 out of 25 for thefifth and the third grades, respectively) with a significant difference between the two groups, the studentsshown to have favorable attitudes about vaccination. The score of the students is not i
... Show MoreInternational Journal on Technical and Physical Problems of Engineering
This research examines the phenomenon of the Arabic language repeated in the Qur'an and poetry, as some morphological formulas are valid in their uses and indications in more than one way. search).