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.
This study looked at how the synthetic chitosan-AgNPs-Doxorubicin-folic acid combination affected the A549 cell line in terms of cytotoxicity and anticancer activity. By reducing silver nitrate (AgNO3) and biodegradable chitosan, silver nanoparticles were biosynthesized. The produced conjugate was examined by using FT-IR spectroscopy, atomic force microscopy (AFM), and field emission scanning electron microscopy (FE-SEM). The cytotoxicity assay for the viability of A549 cells revealed that the combination of chitosan, AgNPs, doxorubicin, and folic acid decrease cell viability in a dose-determined by method over 48 hours, which direct to a dependent reduce in the activity of A549 cells. The mechanism analysis of the impacted living cells lea
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Zerumbone (ZER), a natural compound has been extracted from Zingiber zerumbet with known pharmacological activities. The aim was to determine the anti-human Burkitt’s lymphoma (Raji) cell effect of ZER. The 3-(4,5-dimethylthiazol-2-yl)-2,5,-diphenyltetrazolium bromide (MTT) assay was used to determine cytotoxic effect while the Annexin-V-fluorescein isothiocyanate/propidium iodide-PI flow cytometric assays was used to determine apoptotic effect of ZER on the human Burkitt’s lymphoma (Raji) cell (ATCC CCL-86) cell line. The expressions of Bax, Bcl-2, and c-Myc genes were determined via real-time PCR. ZER suppressed the proliferation of Raji cells with a 48 h IC50 value of 5.1 μg/mL. Treated Raji cells also underwen
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We studied at the morphology, structural setup, and optical characteristics of thin cadmium (CdSe) films a thickness of 250 nm that were created by thermal evaporation over glass, The films exhibited a hexagonal shape were crystalline, and tended to form grains in the (111) crystallographic direction, according to the X-ray diffraction examinations. These characteristics were established using the investigation's findings. Through the use of thin films of CdSe doped with Ag at a concentration of 1.5%, the crystal structure orientations for pure CdSe (25.32, 41.84) and CdSe:Ag (25.39, 41.01) that were both pure as well as those that were doped with silver were both determined. The band gap of the optical spectrum decreased by 1.93–
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Abstract
The environmental conditions are important factors, because they affect both the efficiency of a photovoltaic module and the energy load. This research was carried out experimentally and modeling was done in MATLAB –Simulink by monitoring the variation in power output of the system with environmental conditions such as solar radiation, ambient temperature, wind speed, and humidity of Baghdad city. From the results, the ambient temperatures are inversely proportional to humidity and the output power performance of the system, while the wind speed is directly proportional with the output power performance of the system.
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The apoptotic activity of methionine γ- lyase from Pseudomonas putida on cancer cell lines was indicated by measuring the concentration of cytochrome c in the supernatants of cell lines. The result revealed high concentration of cytochrome c in the supernatants of cancer cell lines (RD, AMGM and AMN3) respectively while the concentration of anti-apoptotic protein (Bcl-2) was very low.
The aim of the study was to know the factors analysis of scale Bar-On & Parker, post analysis is found fourteen factors for the first degree of the scale. Also we extracted five factors from the second degree.
The scale consists of (60) items , applied on sample of (200) students (Male &Female ) age (15-18) years randomly chosen from preparatory schools . The scale unveiled satis factors validity and reliability. An others aims is to low the emotional Intelligence level and know the difference of statistical in sex , age variable and the specialization variable .The result was no difference of statistical in sex and specialization variable , but the difference appear
... Show MoreThe research seeks to identify the contemporary events that face the use of electronic payment methods to localize the salaries of state employees and its impact in enhancing the mental image of customers, and to achieve this purpose from the fact that a questionnaire was designed and distributed to an optional sample of (31) individual customers (employees) dealing With the researched private banks, it has been analyzed and reached a number of conclusions and recommendations, the most prominent of which is the lack of modernity of electronic payment methods by customers, which is reflected in the mental image of customers and the achievement of their satisfaction, in the Emiratization project for salaries needs an advanced leade
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