A numerical computation for determination transmission coefficient and resonant tunneling energies of multibarriers heterostructure has been investigated. Also, we have considered GaN/Al0.3Ga0.7N superlattice system to estimate the probability of resonance at specific energy values, which are less than the potential barrier height. The transmission coefficient is determined by using the transfer matrix method and accordingly the resonant energies are obtained from the T(E) relation. The effects of both well width and number of barriers (N) are observed and discussed. The numbers of resonant tunneling peaks are generally increasing and they become sharper with the increasing of N. The resonant tunneling levels are shifted inside the well by increasing the well width and vice versa. These features and the transmission coefficient as a function of incident energetic particles play an important role in fabrication of high speed devices and a good factor for determination the peak-to-valley ratio of resonant tunneling devices respectively.
The efficiency of egg yolk emulsion in coating DNA and its delivery across cellular membranes was evaluated in comparison with liposomes DOPE . The murine leukemia viral oncogene v-abl , cloned on pBR322 was used as a DNA substrate for direct injection into mice tissue . the DNA complexes were prepared by mixing the DNA with egg yolk emulsion and liposome . Each was directly injected into mice peritoneal cavity with proper control. The gene delivery was examined phenotypically by blood analysis and cytogenetic analysis . Chromosomal changes were detected in the bone marrow as from the fourth day post inoculation through the eleventh day when chromosomal ring s could be seen . this was accompanied by decrease in the WBC count ,
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The means of communication in the accepted human contexts depend on several modes, beginning with the oldest of which in history, represented by the sign language, the sign and the symbol and ending with it, until countless of them became icons that are circulating between the societies themselves or with their neighbors. These icons are often implied in formations that represent a visual discourse which the sender uses as a means and as a message at the same time to express a certain phenomenon in society or in his human self, and thus the sender or performer or artist, in the end, adopted a visual intermediary in order to position his speech in its entirety and perhaps in a specific part of it, to carry the content of that speech and c
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Form of investment in infrastructure important factor to drive economic growth in any country, with the dwindling ability of governments to provide the necessary funds for such investments, emerged as a rising trend for private sector involvement in public projects and infrastructure, and one of these trends is the build-operate-transfer system (BOT), which commonly used in various developed and developing countries as one of the tools used in the implementation of these investments, as the private sector under this system design, finance, build and operate the project, and are re-administration of the state after a certain period under a contractual agreement between the parties of the contract. As this system provides majo
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One hundred thirty seven Staphylococcus spp. isolates were isolated form one hundred fifty clinical specimens which were collected from several hospitals at Al-Sulaimaniya city. Seventy two Staphylococcus aureus isolates, 28 Staphylococcus epidermidis isolates and 37 isolates related to other coagulase negative staphylocci (S. chromogenes, S. lugdunensis, S. cohnii, S. saprophyticus, S. hominis, and S. haemolyticus constituted 3.60%, 2.20%, 2.90%, 2.90%, 6.60%, and 8.80%, respectively). Burn specimens represented the highest (P< 0.05) reservoir for S. aureus and S. epidermidis isolates. Staphylococci developed variable susceptibility to 4 antibiotics (cefoxitin; 30 μg, oxacillin; 1μg, methicillin; 5μg, and cefotaxime; 30 μg). Neve
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Moisture-induced damage is a serious problem that severely impairs asphaltic pavement and affects road serviceability. This study examined numerous variables in asphalt concrete mixtures to assess their impact on moisture damage resistance. Mix design parameters such as the asphalt content (AC) and aggregate passing sieve No. 4 (PNo. 4) were considered as variables during this study. Additionally, hydrated lime (HL) was utilized as a partial substitute for limestone dust (LS) filler at 1.5% by weight of the aggregate in asphalt concrete mixtures for the surface layer. This study also investigated the potential enhancement of traditional asphalt binders and mixtures by adding nano-additives, specifically nano-silica oxide (NS) and na
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We notice that the issue of development is one of the most important issues in ourepoch especially in our country which classify within back ward countries.
When we talk here about the development we don’t mean only the development of capitals or the development of products.but the most important thing is the development of mind .if we notice the experience of developits economy and it didn’t reach to the wanted aim.because these sides . The highness of the meutal rate of the nation is the standard of of the nation is the standard of the sentific and cultural advance for this nation .And that is what we have noticed in human societies ingenerall .
We noticed that
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