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.
What distinguishes human rights issues is their importance to the international community and their importance to democratic political regimes, because they are the axis of any political regime that seeks to achieve a successful democratic path and a stable state. So, countries that are interested in human rights try to enshrine those rights and freedoms in their constitutions and reinforce their concepts in their laws and legislations. Not to mention its involvement in international conventions and treaties concerned with human rights and freedoms, and this is what the Sultanate of Oman has worked on and confirm in the provisions of its 1996 constitution and its amendments
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The composition of the clay taken from the lake of Hamrin, Iraq was studied with the determination of the concentrations of the major oxides and the minor oxides in it. Kaolinite was the most dominant clay in the samples, while quartz was the most abundant non-clay mineral.
Some physico-chemical parameters in lake's water were determined such as oxygen, a chlorosity, nutrient salts, pH, total alkalinity, total nitrogen, total phosphorous and silicate.
The effect of increased wastewater and human activities affected the composition of water and lead to a decrease in the productivity of the lake which was reflected by the relatively low pH values (average 8.0) and alkalinity in water as a result of t
... Show MoreThe research focuses on addressing one of the most important concepts of modern management that deal with the relationship between government institutions and stakeholders, Which now occupies a special significance in trends modern management, a concept of corporate governance it takes the internal mechanisms due to its key role and is important in the process of corporate governance and looking for building Effective mechanisms for this concept in light of laws and regulations that are available in the local environment and on the functioning of government institutions, Search has been applied in the Federal Board of Supreme Audit of Iraq (BSA) due to its particular importance as an institution control and as a awaits the societ
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Homosexuality is one of the important topics that have emerged in recent times in the Islamic and Arab world, as the topic was in the past one of the taboos and majorities and one of the topics that arouse disgust and is talked about secretly and practiced secretly as well.But today, with international and organizational support for this anomaly and its misrepresentation under the name of gender once again and gender again. It began to spread in all countries of the world, including Islamic and Arab countries, and with the presence of associations and influential people in the legislative and judicial authorities of countries that protect and defend homosexuals. Writing on this subject has become a necessity and a duty; to warn against the
... Show MoreThe artistic process operates whether in general in all arts or specifically in one type of arts or one of the genres of arts types on the preoccupations of the pressing artistic references as the founder of the artistic work in the material formulations on the one hand and on the other hand as a translator to understand the artistic achievement in general and plastic art in particular and for the importance The researcher chose the title of her research tagged (the preoccupations of the pressing reference and its impact on the formations of postmodern arts).
The first chapter of the methodological framework deals with the problem of research, importance, objective, limits, and then terminology and its definition, and then the secon
The study aims at finding out:
1. The students' attitude towards the mixed learning at the university.
2. The statistically significant differences in attitude towards the mixed learning at the university according to the specialization variable.
3. The statistically significant differences in attitude towards the mixed learning at the university according to the gender variable.
The researcher has constructed a scale for measuring the students' attitude towards the mixed learning at the university.
After assuring its validity and reliability, the scale has been given to a sample of (100) students. The sample is selected randomly from (4) colleges of the university of Baghdad, (2) for scientific specialization and (2)for h
Transportation Sector classified as one of the services sectors which is without the production activities cannot be complete its rule. Is act asmoving actions which operate at production and non production goals for the organization and individuals insides the country and with others, that is why this sector act as one of the main which is occupied an important status on the way the economic activities and on the level of the economic institutions the transportation work on transforming all the commodities and products from productions locations to consumption location then its effect the productivity process and create the location utility and on the level of economic it considered as one of the economic supportive structure an
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Paul Auster's City of Glass is here singled out as representative of the writer's The New
York Trilogy. All throughout his novelistic career, Auster has been working on a pseudothesis
that adheres to a certain aesthetic of disappearance. The study engages this Austerian
aesthetic apropos of certain theoretical stretches such as the Emersonian "Not Me", the
Thoreauvian "interval" or "nowhere", the Deleuzian "nomadic trajectory", the Derridian
"grammè" or "specter", and the Baudrillardian "disappearance". The city of the novel's titling
is here seen as the trope of all that which has already disappeared, and hence it is seen as the
space (mise en scène) where the perfect crime of the murder of the real is to be thoro