A quantum mechanical description of the dynamics of non-adiabatic electron transfer in metal/semiconductor interfaces can be achieved using simplified models of the system. For this system we can suppose two localized quantum states donor state |D› and acceptor state |A› respectively. Expression of rate constant of electron transfer for metal/semiconductor system derived upon quantum mechanical model and perturbation theory for transition between |ð·âŒª and |ð´âŒª state when the coupling matrix element coefficient is smaller than 0.025eV. The rate of electron transfer for Au/ ZnSe and Au/ZnS interface systems is evaluated with orientation free energy using a Matlap program. The results of the electron transfer rate constant are calculated for our modeas well as with experimental results
Alice Walker (1944) ranks among the greatest American writers of the twentieth century. Through her novels Meridian and the color Purple, Alice outlines many issues concerning the effect of authoritarian thinking upon its often innocent victims, and the possibility of meaningful, productive resistance. Walker's texts aim at giving a voice to those who have no voice especially those poor, rural black women who are robbed of power and the right to make decisions about their own lives by a range of forces standing against them. These texts also aim at clarifying how Walker's female protagonists, Meridian and Celia try to free themselves from oppression, misery , fear and underestimation
... Show MoreIn this study, Yogurt was dried and milled, then shaked with distilled water to remove the soluble materials, then again dried and milled. Batch experiments were carried out to remove hexavalent chromium from aqueous solutions. Different parameters were optimized such as amount of adsorbent, treatment time, pH and concentration of adsorbate. The concentrations of Cr6+ in solutions are determined by UV-Visible spectrophotometer. Maximum percentage removal of Cr6+ was 82% at pH 2. Two equilibrium adsorption isotherms mechanisms are tested Langmuir and Freundlich, the results showed that the isotherm obeyed to Freundlich isotherm. Kinetic models were applied to the adsorption of Cr6+ ions on the adsorbents, ps
... Show MoreThe icon and the symbol represent the constituents of the communication process, through their intellectual and philosophical concepts that have been addressed by the current research that it has touched upon their importance in conveying the design idea for the recipient and showing the specificity of each one of them in the communication process. The research problem has been limited by the following question: what are the communication roles that the symbol and the icon present for the user in designing the industrial product?
The research objective is to reveal the theoretical visualization that describes the icon and the symbol in the industrial product and its importance in the communication process through stating the of simil
The Dammam Formation in S and SW of Iraq is an Eocene carbonate succession consisting of limestone and dolostone. Two boreholes are selected in Al-Najaf and Al-Samawa area to investigate the biostratigraphy. The biostratigraphy of Dammam Formation consist of 22 species which belong to 13 genera of fossils foraminifera.
Two biozones were distinguished in Dammam Formation depending on benthonic foraminifera Nummulites. These biozones are; Nummulites gizehensis range zone and Alveolina sp. – Coskinolina sp. assemblage zone. According to thESE biozones the age of Dammam Formation represent Middle Eocene , whereas absent of these biozone represent Early and Late Eocene.
الاحداث السياسية في العراق بعد 2003 وأثر الانتماء والوعي في التشكيل العراقي المعاصر
Tropical illnesses caused by parasites proceed to cause socioeconomic devastation that reverberate worldwide protozoan parasites, like Leishmania. This parasite has an enormous public health problem in many countries. There is a growing requisite for new control methods for many of these illnesses due to the increasing drug resistance showed by the parasites and problems with drug poisonousness. In this study, fifty-five patients (burns and wounds) were collected from patients from Al-Yarmouk Hospital and Teaching Baghdad Hospital during the period from November, 2015 to January, 2016. Cultural and morphological characteristic examination, biochemical tests were conducted and confirmed the diagnosis by antibiotics sensitivity te
... Show MoreIn this study, a genetic algorithm (GA) is used to detect damage in curved beam model, stiffness as well as mass matrices of the curved beam elements is formulated using Hamilton's principle. Each node of the curved beam element possesses seven degrees of freedom including the warping degree of freedom. The curved beam element had been derived based on the Kang and Yoo’s thin-walled curved beam theory. The identification of damage is formulated as an optimization problem, binary and continuous genetic algorithms
(BGA, CGA) are used to detect and locate the damage using two objective functions (change in natural frequencies, Modal Assurance Criterion MAC). The results show the objective function based on change in natural frequency i
In this paper, isobutane (R-600a) is used as a suitable substitute for (R-134a) when changing the length of capillary tube. And the experimental data on capillary tube are obtained under different conditions such as (subcooling and ambient temperatures) on domestic refrigerator (9ft3 size), this data shows that (R-600a) a suitable substitute for (R134a) .The test presented a model for a steady state, two-phase flow in capillary tube for vapour compression system .The numerical model depends on conservation equations (mass, energy and momentum) as wall as the equation of state for refrigerant. The solution methodology was implemented by using finite difference techniques. The system results indicate that it is possible to change the refri
... Show MoreProduction and characterization of methionine γ- lyase from Pseudomonas putida and its effect on cancer cell lines