Random laser gain media is synthesized with different types of dye at the same concentration (1×10-3 M) as an active material and silicon dioxide NPs (silica SiO2) as scatter centers through the Sol-Gel technique. The prepared samples are tested with UV–Vis spectroscopy, Fluorescence Spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), and Energy Dispersive X-ray Diffraction (EDX). The end result demonstrates that doped dyes with silica nanoparticles at a concentration of 0.0016 mol/ml have lower absorbance and higher fluorescence spectra than pure dyes. FESEM scans revealed that the morphology of nanocrystalline silica is clusters of nano-sized spherical particles in the range (25-67) nm. It is concluded that the various dyes with SiO2 as a scattering center can be proposed to build laser media.
Abstract
Due to the momentum of winning in the streets of the city of Baghdad as a result of the large number of checkpoints so felt researcher to conduct a field visit to find out the main reasons that led to this congestion and to find practical solutions to mitigate wastage winning the arrival time citizen to where you want the least possible time.
This research aims to overcome the difficulties experienced by citizens to reach their places of work and reduce waste at the time of service and waiting time as well as reduce the cost of waiting.
Has emerged study a set of conclusions, including the use of model queue (G / G / C) and the mome
... Show MorePotentiostatic polarization and weight loss methods have been used to investigate the corrosion behavior of carbon steel in sodium chloride solution at different concentrations (0.1, 0.4 and 0.6) M under the influence of temperatures ( 293, 298, 303, 308 and 313) K. The inhibition efficiency of the amoxicillin drug on carbon steel in 0.6 M NaCl has also been studied based on concentration and temperature. The corrosion rate showed that all salt concentrations ( NaCl solution) resulted in corrosion of carbon steel in varying ratio and 0.6 M of salt solution was the highest rate (50.46 g/m².d). The results also indicate that the rate of corrosion increases at a temperature of 313 K.. Potentiodynamic polarization studi
... Show MoreThe aim of this research is to demonstrate the impact of credit risk on the banks of the study sample on the granting of loans and credit facilities, and try to reduce the size of credit risk to banks as a result of granting loans and credit facilities, credit risk is the oldest form of risk in financial markets. Every financial institution takes a degree of risk when it gives loans and credit facilities to companies and customers, It is exposed to financial losses when some borrowers fail to repay their loans as agreed, and at the same time credit facilities are the most profitable operations of the bank as it is the most profitable banking operations than other operations, so it represents the research communit
... Show MoreBreak in the bond and its impact on the difference of scholars
Abstract
The current research aims to clarify the role of local policies on the performance of the province of Baghdad, after studies proved practical experience what those policies of the major role and effect on the lives of citizens, as well as alleviate the burden on central government, which make a lot of states give local governments broad powers and her specialty funds for the exercise of its vital role and actor in various joints of local development, research has indentified a problem in a number of questions such as: do you have the policy of the provincial council of local qualified and able to influence the performance of the province? What are the main forces of powerful and implementation of policies at all
... Show MoreForm recurrence of financial crises phenomenon disturbing and attention , and returns the reasons so that its negative effects were sharp and dangerous , because of the nature and cause of Ncaha , threatened political and economic stability of the countries in which they occur these crises , in addition to Machmlh these crises spread of contagion across multiple channels to include other countries many developed and developing , and the reason for this to the openness of the economic and financial witnessed by the countries affected by crises and other countries concerned, the financial crisis is a case of financial turmoil appears in one of the sections of the financial system one and extends to
... Show MoreThe survey showed sample opinions of officials in the general company for vegetable oils industry, and the statement of the order of the effect of these dimensions depending on the degree of importance, the questionnaire was used as a key tool in collecting data and information of the sample consisted of 30 officials, arithmetic mean, standard deviation, percentages, Spearman correlation coefficient and the global statistical analysis as a statistical methods that based on statistical program (SPSS), The researcher came to several conclusions, most important that there is high agreement by the respondents of the importance of the dimensions of building a mental picture of the company and to attract the consumer's attention, Also research
... Show MoreThe study aimed to identify the effect of Total Quality Management on enhancing competitiveness through the opinions of employees of the front- rows of customer service in local Palestinian banks, the researcher adopted an analytical descriptive method through developing a special questionnaire to accomplish the study’s objectives and answer its questions. The study involved all the Palestinian local banks, with their scattered branches in West Bank. The study sample consisted of 3470 executive employees for banking services out of 4753 employees, in the rate of 73%, and the study sample reached (485) employees who were randomly selected working in the front -rows to provide services in the local Palestinian banks during the ye
... Show MoreOf the importance of the concept of ownership of real estate as the basic basis from which various projects are launched in various economic, tourism, and urban areas .... The need to research the diagnosis of real estate reality went astray in the difficulties, which played a decisive role in the process of urban development.
This leads us to the research problem of the difficulty of implementing urban development plans in many cases due to the absence of a clear methodology for organizing and modernizing the ownership of real estate and its coordination with the management of urban land and to achieve the objective
... Show MoreThe increasing requirement and use of dental implant treatments has rendered dental implantology indispensable in dentistry. The aim of this study is to determine the optimum concentration of calcium silicate to be incorporated into a polyetherketoneketone (PEKK) matrix used as an implant material to enhance the bioactivity and mechanical properties of the composite compared with unmodified PEKK. In this study, different weight percentage (wt%) of micro-calcium silicate (m-CS) is incorporated into PEKK with ethanol as a binder. Subsequently, the mixture is dried in a forced convection oven at 120°C and poured into customized molds to fabricate a bioactive composite via compression molding (310°C, 15 MPa, and 20 min holding time
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