Ag2O (Silver Oxide) is an important p-type (in chasm to most oxides which were n-type), with a high conductivity semiconductor. From the optical absorbance data, the energy gap value of the Ag2O thin films was 1.93 eV, where this value substantially depends on the production method, vacuum evaporation of silver, and optical properties of Ag2O thin films are also affected by the precipitation conditions. The n-type and p-type silicon substrates were used with porous silicon wafers to precipitate ±125 nm, as thick Ag2O thin film by thermal evaporation techniques in vacuum and via rapid thermal oxidation of 400oC and oxidation time 95 s, then characterized by measurement of XRD, optical properties and scanning electron microscopy properties (SEM). Maximum value of photo response obtained from p-Ag2O/p-PS/Si photodetector results revealed two peak sat 600 nm and 800 nm. According to the x-ray diffraction four peaks appear, (111), (200), (110) and (311) Ag, respectively, (polycrystalline film) and lattice constant of (4.077 Å). Also the results showed a sharp increasing in the absorption-wave length plot of Ag2O film at UV and IR regions. The accumulation of the stars-like are semi-regular of the Ag2O nanocrystals on the surface of p-type PS and the other diffuse inside the pores in a nearly uniform distribution with a different grain size on the surface. The results of the dislocation density and strain are decreased with the grain size increasing.
<p>The objective of this paper is to study the dynamical behavior of an aquatic food web system. A mathematical model that includes nutrients, phytoplankton and zooplankton is proposed and analyzed. It is assumed that, the phytoplankton divided into two compartments namely toxic phytoplankton which produces a toxic substance as a defensive strategy against predation by zooplankton, and a nontoxic phytoplankton. All the feeding processes in this food web are formulating according to the Lotka-Volterra functional response. This model is represented mathematically by the set of nonlinear differential equations. The existence, uniqueness and boundedness of the solution of this model are investigated. The local and global stability
... Show MoreThis research is concerned with the study of (the dialectic of the familiar and the unfamiliar in Islamic photography), and it consists of four chapters.
If you dealt with the problem of the research subject (the dialectic of the familiar and the unfamiliar in Islamic photography, as it appeared realistic, familiar forms and strange and strange unfamiliar forms represented in many of the main schools of Islamic photography that emerged in Iraq and Persia and then the Ottomans and the However, Islamic painting still retains those previously witnessed and unseen images, which pose themselves forcibly in the form of many questions that must be faced and studied by investigation, observation, extrapolation and conclusion through scientifi
This research deals with the aesthetics of describing nature and the joys of urban life in the environment of Fatimid Egypt, among a group of poets, who were deceived by its enchanting beauty and breathtaking scenery, through it they depicted the reality of the life they live, and the things that involved them, as well as showing their personal culture, and the joys of life that experience, articulating this with a descriptive and analytical study, focusing on how the poet portrayed the visual scene, in an important stage of Arabic literature in Egypt.
The research on coordination polymers chemistry based on organic-metal framework with bridging ligands has accelerated during the past two decades. It is an interested hot topic in the synthetic inorganic chemistry, which allowed the fabrication of a variety of interested materials. These materials have shown a range of applications including light harvesting and magnetic properties. The thesis is divided in three chapters. The first chapter gives a general introduction on the development of self-assembled polymeric species based on transition metal. It is also covered a summary of the literature review on the current state of the art on self-assembled coordination ploymers. Furthermore, it includes a description on various relevant topics
... Show MoreBackground: Hodgkin's lymphoma (HL), formerly called Hodgkin's diseases is an uncommon form of lymphoma. The incidence of Hodgkin's lymphoma shows marked heterogeneity with respect to age, gender, race, geographic area, social class and histological subtype. This study was carried out in an attempt to evaluate the incidence of Hodgkin's lymphoma of head and neck in Baghdad city. Materials and Methods: The diagnosed cases of Hodgkin's lymphoma of head and neck region in Baghdad city between (1990-1999) were collected and analyzed according to age, gender, site and the histopathological subtypes of the tumor. Results: Out of (702) cases of Hodgkin's lymphoma of ten years between (1990-1999),(362 ) of them were occurred in the head and neck
... Show MoreLaboratory experience in Iraq with cold asphalt concrete mixtures is very limited. The design and use of cold mixed asphalt concrete had no technical requirements. In this study, two asphalt concrete mixtures used for the base course were prepared in the laboratory using conventional cold-mixing techniques to test cold asphalt mixture (CAM) against aging and moisture susceptibility. Cold asphalt mixtures specimens have been prepared in the lab with cutback and emulsion binders, different fillers, and curing times. Based on the Marshal test result, the cutback proportion was selected with the filler, also based on the Marshal test emulsion. The first mixture was medium setting cationic emulsion (MSCE) as a binder, hydrate
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