The article describes a study on the role of vitamin C as a protective agent for the teeth, gum, and implants using quantum chemical calculations and polarization tests. The Density Functional Theory (DFT) at 6-311G (d, p) basis set is used to estimate the ability of vitamin C to inhibit the corrosion of the abovementioned parts. The experimental study was performed in a at human body media simulator (Hank’s balanced salt solution) at a temperature of 37°C. The compound was optimized for its ground state, physical properties, and corrosion parameters. Further, HOMO, LUMO, energy gap, dipole moment, and other parameters were used to predict the inhibitor’s efficiency. Gaussian 09, UCA-FUKUI, MGL tools, DSV, and LigPlus software was used

This study comprised three traverses extending parallel through the Northern, Central and Southern Mahmudiya districts, and perpendicular to the course of the Euphrates River. They were identified to collect (15) soil samples and some water samples as distributed within the land cover classes of the study area. Those classes were determined by visual interpretation and supervised classification for Landsat (TM) images obtained in August/2007. The digital classification was based on Maximum Likelihood method using six spectral bands excluding the thermal band. Chemical and physical laboratory analysis for the soil characteristics was performed to determine the types of land degradation in the study area.
The results showed that the hig

The aim of this study is to investigate the behavior of composite castellated beam in which the concrete slab and steel beam connected together with headed studs shear connectors. Four simply supported composite beams with various degree of castellation were tested under two point static loads. One of these beams was built up using standard steel beam, i.e. without web openings, to be a reference beam. The other three beams were fabricated from the same steel I-section with various three castellation ratios, (25, 35, and 45) %. In all beams the concrete slab has the same section and properties. Deflection at mid span of all beams was measured at each 10 kN load increment. The test results show that the castellation process leads to

This current research aims to reveal the difference between the levels of teaching expertise of physics teachers according to the years of service by answering the following question: does the educational skill level of physics teachers work according to the service? The sample of the study consisted of (225) physics teachers by (125) females (56%), and (100) males (44%), distributed on (4) education directorates in Baghdad governorate on both sides of al-Karkh and al-Rusafa. In order to achieve the aim of the study, the researcher prepared a note card for expertise teaching, consisting of (39) paragraphs distributed into (5) fields. The apparent validity and reliability of the card were verified through an agreement (the researcher hers

An epidemiological study in Al-Mahmmodiya (50 km south Baghdad) to investigate a possible vector of Leishmaniasis were applied .This region is considered as a foci of Leishmaniasisaccording to the health association statistics. CDC light traps were used to collect the insects nightly. Insects were collected by Indoor application as human dwellings and animal shelters and Outdoor application as rodent's barrows and field trees. Sand flies were transported to the laboratory, isolated and identified according to the identification keys in Tropical Biological Researches Unit at the Collage of Science / University of Baghdad. Must of the collected sand flies were belonging to three species PhlebotomuspapatasiScopoli(45%), PhlebotomusalexandriSin

In this paper, the density of state (DOS) at Fe metal contact to Titanium dioxide semiconductor (TiO2) has been studied and investigated using quantum consideration approaches. The study and calculations of (DOS) depended on the orientation and driving energies. was a function of TiO2 and Fe materials' refractive index and dielectric constant. Attention has focused on the effect of on the characteristic of (DOS), which increased with the increasing of refractive index and dielectric constant of Fe metal and vice versa. The results of (DOS) and its relation with and values of system have been discussed. As for contact system is increased, (DOS) values increased at first, but the relation is disturbed later and transforms into an inve

Al-Si alloys which are widely used in engineering applications due to their outstanding properties can be modified for more enhancements in their properties. Current work investigated the ability of these alloys to be modified by casting them through the addition of nanoparticles. So, Multi-wall carbon nanotubes (CNT) and titanium carbide ceramic particles (TIC) with size of (20 nm) were added with different amounts started from (0.5 up to 3%) weight  to cast alloy A356 that was considered to be the base metal matrix, then stirred with different speeds of (270, 800, 1500, 2150) rpm at 520 °C for one minute. The results showed change in microstructure’ shape of the casted alloys from the dendritic to spherical gra

The main aim of this research is to: 1) identify the Transformational Leadership of the Managers of higher School in ALkut district and its relationship with organizational Loyalty. 2) Clarify the relationship between Transformational Leadership and organizational Loyalty. Regarding the research methodology, the researcher used the descriptive method because it meets this research. The two research tools were a questionnaire and the statistical program (spss). The results revealed that there is a strong positive relationship between Transformational Leadership and organizational Loyalty, which means that when the managers have a Transformational Leadership leads to having organizational loyalty.