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.
This research studies the development and synthesis of blended nanocomposites filled with Titanium dioxide (TiO2). Blended nanocomposites based on unsaturated polyester resin (UPR) and epoxy resins were synthesized by reactive blending. The optimum quantity from nano partical of titanium dioxide was selected and different weight proportions 1%, 3%, 5%, and 7% ratios of new epoxy are blended with UPR resin. The dielectric breakdown strength and thermal conductivity properties of the blended nanocomposites were compared with those of the basis material (UPR and 3% TiO2).The results show good compatibility epoxy resins with the UPR resin on blending, dielectric breakdown strength values are higher while thermal conductivity values of
... Show MoreScience is linked to each other bonds assets, branches and even close to each other; to become a link of this type of patterns of scientific integration, and perhaps the most prominent science that saw the overlap and interdependence of science and jurisprudence and its origins, and this interdependence did not stop at the epistemological foundations of knowledge; To the branches, methods of extraction, and diligence to extend to the terminology; to find similar terms in both flags; to become those terms similar in the word and meaning and even the end, but we do not lack terms similar in pronunciation and differing in meaning; and this difference is imposed by the specificity of each science and what M E; however, approached many terms
... Show MoreIn this research the hard chromium electroplating process, which is one of the common methods of overlay coating was used, by using chromium acid as source of chromium and sulphuric acid as catalyst since the ratio between chromic acid and sulphuric acid is (100 : 1) consequently. Plating process was made by applying current of density (40 Amp / dm2) and the range of solution temperature was (50 – 55oC) with different time periods (1-5 hr). A low carbon steel type (Ck15) was used as substrate for hard chromium electroplating. Solid carburization was carried out for hard chromium plating specimen at temperature (925oC) with time duration (2 hr) to be followed with quenching and tempering
... Show MoreThe research aims to determine the role of the practices of green human resources management in achieving requirements of environmental citizenship in the workplace, the General Company for Vegetable Oils was chosen for the application of field-side of research which represent one of the important industrial companies in Iraq, which suffers from poor Green human resources management applications, which reflected negatively on the development Environmental citizenship among Employees. The questionnaire use as a tool to collect data and information as well as field presence of the researcher, The research sample included (30) managers of departments and Division ,and through using statistical program (SPSS) the data has been analys
... Show MoreThe contractual imbalance is perceived today by the majority of the doctrine as being one of the pitfalls to the execution of the contracts. As a result, most legislations grant judges the power to intervene to restore it. Granting the judge the power to complete the contract raises the question of the extent to which the judge can obtain such power. Is it an absolute authority that is not limited? If so, is it a broad discretion in which the judge operates in his conscience, or is it a power of limited scope by specific legal texts and conventions? This is what we will try to answer in this research.
Background: Bisphosphonates are potent inhibitors of osteoclastic bone resorption and widely used for the treatment of osteoporosis, and osteogenesis imperfecta in children. Clinical and experimental studies have demonstrated that Bisphosphonates delay or inhibit tooth eruption. This study tries to focus on the effect of bisphosphonate on teeth development and jaw bones growth. Materials and methods: The present study includes 65 neonatal rats during lactation period from 15 Albino Wister rats mother. Alendronate (one type of Bisphosphonates) was administrated orally (15 mg/kg) into 10 pregnant rats two times a week, while other 5 rats regard as control. Then the neonatal rats sacrificed in I, 6, 11, 16 and 21 days. The lower first molar we
... Show MoreThe environmental contamination by the polycyclic aromatic hydrocarbons (PAHs) and heavy metals (Pb, Cu, Ni, Cr, and Cd) concentrations in the leaves of plant Eucalyptus camaldulensis were determined at the city of Kirkuk in 15 selected locations using GPS. The pickings up of samples were carried out in two periods October 2010 and March 2011. Compared with results of other studies, the concentration levels of determined heavy metals show values within these studies results. The average total concentration of polycyclic aromatic hydrocarbons (PAHs) in the leaves of Plant Eucalyptus camaldulensis indicated 37.1 ppb in October, while in March 165.2 ppb.
The mode
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