Background Alloys with the addition of zirconium and niobium eliminate the adverse effects of aluminum and vanadium on the nervous system, the possibility of metallosis and the initiation of diseases (including cancers or Alzheimer›s disease). In addition, they have better corrosion resistance, and a Young›s modulus value similar to longitudinal bone tissue. Therefore, only choosing appropriate materials does not guarantee proper functioning of the implants, the surfaces of the implants also have to be suitable to meet the requirements. The laser surface hardening process modifies the surface properties by imparting microstructural changes, whereas surface remelting induces changes in the surface topography, roughness, wettability and wear and corrosion resistance, influencing the biocompatibility of the surface. Such changes are brought in essentially because of the characteristic melting, evaporation and rapid solidification during laser surface remelting processes. Objectives This study was aimed at evaluating the electrochemical corrosion of commercial pure Titanium disks (CP Ti) and the Ti13Zr13Nb (Alloy) with a zigzag pattern of laser surface treatment. Materials and Methods a total of 40 discs of Cp Ti & 40 of Ti13Zr13Nb were fabricated. The surfaces of the test groups were treated with unique zigzag patterns using CNC Laser treatment on the texturing surfaces, the samples then are analyzed by using XRD, microhardness and electrochemical corrosion tests. Results The study revealed a proper increase in the surface hardness and corrosion resistance without crack formation or a dramatic change of the core substance of the CP Ti and Alloy disks. Conclusion The CNC laser is considered an effective and suitable method for surface texturing of CP Ti and Alloy for dental implantology.
This article will address autoclave design considerations and
manufacturing working with high pressure low temperature
supercritical drying technique to produce silica aerogel. The design
elects carbon dioxide as a supercritical fluid (31.7 oC and 72.3 bar).
Both temperature and pressure have independently controlling
facility through present design. The autoclave was light weight (4.5
kg) and factory-made from stainless steel. It contains a high pressure
window for monitoring both transfer carbon dioxide gas to liquid
carbon dioxide and watching supercritical drying via aerogel
preparation process. In this work aerogel samples were prepared and
the true apparent densities, total pore volume and pore size
The study included a statement toxicity of some heavy metals individually and collectively and the existence of plant nutrients in the center Agirenk bluish green moss growth and Askhaddm biomass as an indicator of the study, in addition to portability moss on the accumulation of the metal
A sensitive spectrofluorimetric method for the determination of glibenclamide in its tablet formulations has been proposed. The method is based on the dissolving of glibenclamide in absolute ethanol and measuring the native fluorescence at 354 nm after excitation at 302 nm. Beers law is obeyed in the concentration of 1.4 to 10 µg.ml-1 of glibenclamide with a limit of detection (LD) of 0.067 µg.ml-1 and a standard deviation of 0.614. The range percent recoveries (N=3) is 94 - 103.
In this paper, our aim is to study variational formulation and solutions of 2-dimensional integrodifferential equations of fractional order. We will give a summery of representation to the variational formulation of linear nonhomogenous 2-dimensional Volterra integro-differential equations of the second kind with fractional order. An example will be discussed and solved by using the MathCAD software package when it is needed.
Background: The aim of this study was to measure the radiopacity (RO) of modified microhybrid composite resins by adding 2 types of nanofillers (Zinc Oxide and Calcium Carbonate) in two concentrations 3% and 5% and comparing them to unmodified microhybrid composite resins and to nanofilled composite resin. Materials and Methods: Two types of composite resin were used (Microhybrid composite MH Quadrent anterior shine and Nanofilled composite resin Filtek Z350 XT), for each tested group five disk-shaped specimens (1-mm-thick and 15 mm diameter) were fabricated. The material samples were radiographed together with the aluminum step wedge. The density of the specimens was determined with a transmission densitometer and was expressed in term of
... Show MoreBackground: The World Health Organization was declared COVID-19 a pandemic on March 11, 2020. As a result, to keep the coronavirus under control, protective technique like face covering is required. Vaccination, on the other hand, is regarded as a preventative and effective measure. As nursing students play an important role in the future of nursing, their perception regarding wearing mask and taking vaccine can be crucial in preventive measures regarding COVID-19. Objective: The purpose of this study was to assess the perception of nursing students’ regarding wearing mask and coronavirus vaccines. Design: A descriptive correlational design was used to guide this study. Settings and Participants: A total of 255 undergraduate
... Show MoreIn the present work, 9-fluorenone-2-carboxylic acid methyl ester (1) was prepared from 9-fluorenone-2-carboxylic acid and then converted into the acid hydrazide (2). Compound (2), is the key intermediate for the synthesis of several series of new compounds such as substituted 1,3,4-oxadiazole derivatives (3-6) were synthesized from the condensation of different substituted benzoic acids with compound (2) using POCl3 as condensing agent. Treatment of compound (2) with formic acid gave the N-formyl hydrazide (7), which upon refluxing with phosphorous pentoxide in benzene yielded the corresponding 5-(9-fluorenone-2-yl)-1,3,4-oxadiazole (8). Reaction of hydrazide (2) with phenyl isocyanate to give N-phenyl semicarbazide derivative (9), then thi
... Show MoreConducted two trials separate plants Defla first two seasons, 1998 and 1999 to test the susceptibility Altgveria three varieties including Azharha colored white and pink Qati and pink Qtmr and second seasons 1999 and 2000, two types color Azhaarhama white and pink Qati treated mind half-timbered two types of Alaoxinat IBA and NAA and three concentrations as well as repeatersAdhrt results low Almaah rooting