This research aims to study the optical characteristics of semiconductor quantum dots (QDs) composed of CdTe and CdTe/CdSe core-shell structures. It utilizes the refluxed method to synthesize these nanoscale particles and aims to comprehend the growth process by monitoring their optical properties over varied periods of time and pH 12. Specifically, the optical evolution of these QDs is evaluated using photoluminescence (PL) and ultraviolet (UV) spectroscopy. For CdTe QDs, a consistent absorbance and peak intensity increase were observed across the spectrum over time. Conversely, CdTe/CdSe QDs displayed distinctive absorbance and peak intensity variations. These disparities might stem from irregularities in forming selenium (Se) layers around CdTe QDs during growth stages, which could potentially induce quenching in the emission spectrum. The optical examinations unveiled a discernible redshift towards higher wavelength values as the reaction progressed. This spectral shift was coupled with an enlargement in QDs size and a decrease in the energy gap. Using PL and UV analysis techniques enabled a comprehensive study of the optical attributes of the CdTe and CdTe/CdSe QD systems. Our findings underscored the influence of growth conditions and shell materials on the optical properties of QDs. The observed changes in absorbance, peak intensity, wavelength values, QDs size, and energy gap with increasing reaction time provided valuable insights into the growth dynamics of these QD structures.
Evaluation of trace elements in Iraqi chewing gums are unavailable, particularly pollution of toxic elements, materials which change the values of PH in the Oral. Atomic Absorption Spectroscopy (AAS) were successfully employed to determine the concentration of 7 trace elements (essentially toxic and nonessential) and the PH, in thirteen different brands of chewing gum generally consumed in Iraq. Combined wet and dry digestion procedures were applied. Two types of heated graphite tubes were used, coated and uncoated tubes treated with tungsten solution. Result showed that Cu, Al and Zn were at very high levels in almost all brands whereas Mn was found to be high in brands A and O only.
This study carry’s out the correlation and the effect of two main variables, these variables are Job Satisfaction included six sub: wages - salaries and justice and yield, working conditions and services, pattern of supervision and the relationship with the manger, Relationship with colleagues, the content of the work and the variety of tasks, development and promotion opportunities available to an individual, and Organizational Performance included two sub variables: Efficiency, Effectiveness. This research was conducted using a questioner as a main tool, This questioner was distributed randomly to a research community composed of
... Show MoreCarrageenan extract is a compound of sulfated polyglycan that is taken out from red seaweeds. Being hydrocolloid in nature, carrageenan has gelling, emulsifying and thickening properties allowing it to be commonly used in the oral healthcare products and cosmetics. Due to its bioactive compounds, carrageenan has been shown to have antimicrobial, antiviral, and antitumor properties. The purpose of this work is to study the probable use of carrageenan on the diseases that are related to oral cavity and on the genomic DNA in in vitro experimental model
In this study, the effects of k-carrageenan on four different cell lines related to the cancer and normal cells which cultured on selective media were done. Moreover, the eff
... Show MoreThe economic units always sought to maintain its market position and Trchinh the technology management and modern methods that will support success factors .vdila about it has become a customer and one profitability analysis of the most practical way benefit of economic units as modern management focus their attention on achieving this satisfaction, as the customers make up the axis of the success of every organization and that there are many government units aiming to profit directs attention to customers and the number of these units increased continuously. The administration used the customer profitability analysis in order to obtain information to assist in making and decision-making process. How to use modern tec
... Show MoreBackground: Laser is a novel physical therapy technique used to treat various conditions, including wound healing, inhibition of bacterial growth, and postoperative wounds. High-power pulsed alexandrite laser therapy is one of the most prevalent forms of laser therapy, which is a noninvasive method for treating various pathological conditions, thereby enhancing functional capacities and quality of life. It is a modern medical and physiotherapeutic technology. Generally, the Alexandrite laser emits infrared light with a wavelength of 755 nm, allowing it to propagate and penetrate tissues. Objective: This study focused on the application of a high-power pulsed alexandrite laser in vitro to evaluate the effect of a pulsed alexandrite l
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