Ab – initio restricted Hartree - Fock method within the framework of large unit cell (LUC) formalism is used to investigate the electronic structure of Si and Ge nanocrystals. The surface and core properties are investigated. A large unit cell of 8 atoms is used in the present analysis. Cohesive energy, energy gap, conduction and valence band widths are obtained from the electronic structure calculations. The results are compared with available experimental data and theoretical results of other investigators. The calculated lattice constant is found to be slightly larger than the corresponding experimental value because we use only 8 atoms and we compared the results with that of the bulk crystals, nanoclusters are expected to have stronger directional bonds that in their bulk structure. The surface states are found to be mostly non-degenerated because of the effect of surface discontinuity and the existence of oxygen atoms. Valence and conduction bands are found to be wider on the surface due to the splitting of energy levels due to the existence of oxygen atoms. The present method can be used to investigate the electronic structure of bulk, surface and nanocrystals.
Innovative laboratory research and fluid breakthroughs have improved carbonate matrix stimulation technology in the recent decade. Since oil and gas wells are stimulated often to increase output and maximum recovery, this has resulted in matrix acidizing is a less costly alternative to hydraulic fracturing; therefore, it is widely employed because of its low cost and the fact that it may restore damaged wells to their previous productivity and give extra production capacity. Limestone acidizing in the Mishrif reservoir has never been investigated; hence research revealed fresh insights into this process. Many reports have stated that the Ahdeb oil field's Mishrif reservoir has been unable to be stimulated due to high inj
... Show MoreThis work is divided into two parts first part study electronic structure and vibration properties of the Iobenguane material that is used in CT scan imaging. Iobenguane, or MIBG, is an aralkylguanidine analog of the adrenergic neurotransmitter norepinephrine and a radiopharmaceutical. It acts as a blocking agent for adrenergic neurons. When radiolabeled, it can be used in nuclear medicinal diagnostic techniques as well as in neuroendocrine antineoplastic treatments. The aim of this work is to provide general information about Iobenguane that can be used to obtain results to diagnose the diseases. The second part study image processing techniques, the CT scan image is transformed to frequency domain using the LWT. Two methods of contrast
... Show MoreMotivated by the vital role played by transition metal nitride (TMN) composites in various industrial applications, the current study reports electronic properties, thermodynamic stability phase diagram, and vacancy formation energies of the plausible surfaces of NiAs and WC-type structures of δ3-MoN and δ-WN hexagonal phases, respectively. Low miller indices of various surface terminations of δ3-MoN and δ-WN namely, (100), (110), (111), and (001) have been considered. Initial cleaving of δ3-MoN bulk unit cell offers separate Mo and N terminations signified as δ3-MoN (100): Mo, δ3-MoN(100):N, δ3-MoN(111):Mo, δ3-MoN(111):Mo, and δ3-MoN(001):Mo. However, the (110) plane reveals mix-truncated with both molybdenum and nitrogen atoms i
... Show MoreObjectives: To assess the pediatric nurses' knowledge about the nosocomial infection owl), and to fud out the
relatiouships between their knowledge about the nosocomial infection and demographic data.
Methodology: A descriptive study was carried out at neonatal intensive care units OVICUs) of Baghdad
Pediatric Teaching Hospitals. It was started from the end of April to the end of October, 2008. A purposive
sample of (28) pediatric nurses were selected. The data were collected by self-administered questiormaire. The
validity of the questionnaire was detemined through a panel of experts, while its reliability was detemined
through the pilot study. The data were analyzed by descriptive and inferential statistics through th
This study presents a histological comparison of the esophagus between squirrels and mongooses, illustrating herbivorous and carnivorous dietary adaptations, respectively. Histological sections were examined from both species to compare the tunica mucosa, submucosa, muscularis, and adventitia. Esophageal samples were collected from adult specimens that were stained with hematoxylin and eosin (H&E) and Masson’s trichrome, then examined microscopically. Results revealed that squirrels exhibited a thick wall with non-keratinized epithelium and fully striated muscularis, reflecting a plant-based diet. In contrast, mongooses displayed regional variation in wall thickness and thinner mucosa in the upper third and a transition from s
... Show MoreThe current research deals with the argument of delusion and interpretation in the direction structure and its reflected impact in the reception activity and the amount of conceptual displacement it is subjected to in an aesthetic approach to abstract conceptual definitions of the reception activity , by the effect of this dialectic in the direction structure, which can be summed up by the following question: (What are the characteristics of the direction structure of the imaginary and what is the argument of interpretation in the theatre reception activity?) in order to stand on the aesthetic framework and conceptual definition of the direction structure in the controversy of interpretation and imagination, and its impact on the concept
... Show MoreDespite that cardiovascular disease (CVD) is the main cause of death in women worldwide and that the existent evidence that women with CVD differs from men with the same diseases from many views including pathophysiological to therapeutic. Yet, there is an unmet need for registries focused on sex differences in CVD, as the first step toward patient-centered trials, guidelines, and protocols. To the best of our knowledge, there has been no prior registry focusing exclusively on CVD in women with sex-focused research questions and methodology thus far.
The Iraqi Registry of Cardiovas