The present work describes the adsorption of Ba2+ and Mg2+ions from aqueous solutions by activated alumina in single and binary system using batch adsorption. The effect of different parameters such as amount of alumina, concentration of metal ions, pH of solution, contact time and agitation speed on the adsorption process was studied. The optimum adsorbent dosage was found to be 0.5 g and 1.5 g for removal of Ba2+ and Mg2+, respectively. The optimum pH, contact time and agitation speed, were found to be pH 6, 2h and 300 rpm, respectively, for removal of both metal ions. The equilibrium data were analyzed by Langmuir and Freundlich isotherm models and the data fitted well to both isotherm modes as indicated by higher correlation of determination R2> 0.87 in both single and binary systems. Pore diffusion model for batch adsorption was used to predict the concentration decay curve for adsorption of Ba2+ and Mg2+ onto activated alumina. There was a good agreement between the experimental data and the predicted decay curves using pore diffusion model.
This study evaluated the extent to which obturation materials bypass fractured endodontic instruments positioned in the middle and apical thirds of severely curved simulated root canals using different obturation techniques. Sixty resin blocks with simulated root canals were used, each with a 50° curvature, a 6.5 mm radius of curvature, and a length of 16.5 mm, prepared to an ISO #15 diameter and taper. Canals were shaped using ProTaper Universal files (Dentsply Maillefer) attached to an X-smart Plus endo motor (Dentsply), set at 3.5 Ncm torque and 250 rpm, up to size S2 at working length. To simulate fractures, F2 and F3 files were weakened 3 mm from the tip, then twisted to break in the apical and middle sections of the canal, re
... Show MoreBackground: Healing of a tooth extraction socket is a complex process involving tissue repair and regeneration. It involves chemotaxis of appropriate cells into the wound, Transformation of undifferentiated mesenchymal cells to osteoprogenitor cells, proliferation and differentiation of committed bone forming cells, extracellular matrix synthesis, mineralization of osteoid, maturation and remodeling of bone. These cellular events are precisely controlled and regulated by specific signaling molecules. Some of these like transforming growth factor beta (TGF-?), vascular endothelial growth factor (VEGF), bone morphogenetic proteins (BMP) and insulin like growth factors (IGF) are well conserved proteins involved in the initial response to injur
... Show MoreWith the increasing demands to use remote sensing approaches, such as aerial photography, satellite imagery, and LiDAR in archaeological applications, there is still a limited number of studies assessing the differences between remote sensing methods in extracting new archaeological finds. Therefore, this work aims to critically compare two types of fine-scale remotely sensed data: LiDAR and an Unmanned Aerial Vehicle (UAV) derived Structure from Motion (SfM) photogrammetry. To achieve this, aerial imagery and airborne LiDAR datasets of Chun Castle were acquired, processed, analyzed, and interpreted. Chun Castle is one of the most remarkable ancient sites in Cornwall County (Southwest England) that had not been surveyed and explored
... Show MoreHarriet Jacobs was a writer and a reformer. As a female writer in the nineteenth century, Jacobs wrote her narrative as a means of resisting the system of slavery. She wrote her book Incidents in the Life of a Slave Girl: Written by Herself, (1842) to reflect upon the exploitation of the black people and the need to change the hierarchal attitude that governs white/black relations. She was engaged in many abolitionist events and her anti-slavery approach appeared clearly in her writings. She shares Du Bios ideas about freedom and emancipation and the need for a political and cultural change. Thus, Du Bois’s theory provides a framework for her autobiographical novel where she portrays Linda Brent, the main character, a strong w
... Show MoreThis research studies the Saudi women participation in the visual arts, presents descriptive and analytical overview on their artworks and assess development through their participation in the said exhibition, frequency of participation, and aims to understand the most important stages and changes of the subjects addressed, artistic styles and the factors affecting these results in view of female artist's attitude pertaining to several aspects such as administrative organization, judging committees etc.
Interviews were held with a sample of female artists, 17 artists from different regions and generations out of 182 participants and reviewed relevant exhibition literature during the period 1979-2018. The research problem is to id
... Show MoreA histological study showed the wall of the stomach in Pica pica and Herpestes javanicus consists of four layers: mucosa, submucosa, muscularis externa and serosa. Also, the present study showed many differences in the histological structures of the stomach for each in both types. The stomach of P. pica consists of two portions: the proventiculus and gizzard, while the stomach of H. javanicus consists of three portions: cardiac, fundic and pyloric regions. The mucosa layer formed short gastric folds, named plicae. In the proventiculus of P. pica, sulcus is found between each two plicae, but the folds called gastric p
... Show MoreA histological study showed the wall of the stomach in Pica pica and Herpestes javanicus consists of four layers: mucosa, submucosa, muscularis externa and serosa. Also, the present study showed many differences in the histological structures of the stomach for each in both types. The stomach of P. pica consists of two portions: the proventiculus and gizzard, while the stomach of H. javanicus consists of three portions: cardiac, fundic and pyloric regions. The mucosa layer formed short gastric folds, named plicae. In the proventiculus of P. pica, sulcus is found between each two plicae, but the folds called gastric pits in the gizzard, which are full with koilin. Lamina properia in both types contained gastric g
... Show MoreThe aim of this research is to estimate the parameters of the linear regression model with errors following ARFIMA model by using wavelet method depending on maximum likelihood and approaching general least square as well as ordinary least square. We use the estimators in practical application on real data, which were the monthly data of Inflation and Dollar exchange rate obtained from the (CSO) Central Statistical organization for the period from 1/2005 to 12/2015. The results proved that (WML) was the most reliable and efficient from the other estimators, also the results provide that the changing of fractional difference parameter (d) doesn’t effect on the results.
The research has arrived to the following results:
1. There were critical views that accompanied the beginnings of (Muwashah). These
views were derived from literary criticism that handled the ancient Arabic poetry, especially
its kinds that were concerned with artificiality in addition to the views based on rivalry
among makers of (Muwashah) in front of the audience so as to judje who is the best
according to artistic response.
2. There existed new critical views, their originality was shown through the new critical
theories that appeared especially those concerned with receiving the text and reading theory.
3. The Muwashah was one of the most important poetic arts that reproduced previous
text, not in the tra