The nonlinear refractive index and the nonlinear absorption coefficient of unmodified and functional poly(methyl methacrylate) PMMA films were studied before and after the addition of the filler by the z-scan technique, using a Q-switched Nd:YAG laser at two wavelengths: 532 nm and 1064 nm, and at three input energies (13, 33 and 53) mJ. Both linear and nonlinear refractive indices and absorption coefficients of polymer films were studied by using UV-VIS spectrophotometer. The results show that the creation of functional PMMA from unmodified PMMA will increase the nonlinear optical properties in the functional PMMA/copper matrix more than in the unmodified PMMA/copper matrix. Hence, the functional PMMA appears promising as a useful third-order nonlinear material. The nonlinear refractive index is directly proportional to the input intensity and directly proportional to the increase in the concentration of the filler, while the nonlinear absorption coefficient is inversely proportional to the input energy and inversely proportional to the increase in the concentration of the filler. The nonlinear effect is more enhanced at the 532 nm wavelength than at 1064 nm..
This research delts with study seven species of seeds and wild varieties wild belonging to the genus Medicago L., these species are: M. constricta Dur., M. coronata (L.) Bartal., M. intertexta (L.) Mill., M. intertexta.var. ciliaris (L.) Hyen., M. laciniata (L.) Mill., M. lupulina L., M. minima (L.) Bartal. and M. sativa L., the research involved characteristics of shapes, dimensions, colors and the nature of the surface ornamentation of seeds and also the hilum site. the seeds forms ranged between crescent, reniform and ovate, in addition there was a clear difference in seeds dimensions in height and width, while, the color has been vary between light brown to brown and dark brown. The nature of the surface ornamentation was smooth, retic
... Show MoreA particulate polymer composite material was prepared by reinforcing with the Aluminum Oxide (Al2O3) or Aluminum (Al) metallic particles with a particle size of (30) µm to an unsaturated Polyester Resin with a weight fraction of (5%, 10%, 15%, 20%).
Tensile test results showed the maximum value of elastic modulus reached (2400MPa.) in the case of reinforcing with (Al) particles with weight fraction (20%) and (1500 MPa.) in the case of reinforcing with (Al2O3) particles of the same weight fraction.
When the impact and the flexural strength tests were done, the results showed that flexural strength (F.S), maximum shear stress (τmax), impact strength
... Show MoreThis research concerns the fact of the school garden and how can we tackle this issue. The research starts with a question forwarded to those who are interested in the ministry of education matters; the question is that how is the extent of interest in the school garden project? And how it is activated in the Iraqi Educational Institution program? In addition, the analysis reveals the importance of the school garden since we, as teachers and students, suffer from seeing the view of the trashes, the wastes of school furniture, the stinking water and the weeds and how it is accumulated in the back yard of the school. To add fuel to the fire, the increase in number of the students; year after year. This increase leads to adding more classes
... Show MoreThe dividends is one of difficult and important decisions taken by the administration in the economic units, because this decision has a direct impact on the investor and economic unit, so the main objective of any investor is achieve earnings, as well as information borne by dividends about the earnings quality of the economic unit and the level and efficiency of management to achieving earnings.
The research aims at explaining the effect of the dividends policy on the earnings quality in the companies listed in the Iraq Stock Exchange. The Miller model was used to measu
... Show MoreDue to the energy crisis and the stringent environmental regulations, diesel engines are offering good hope for automotive vehicles. However, a lot of work is needed to reduce the diesel exhaust emissions and give the way for full utilization of the diesel fuel’s excellent characteristics.
A kind of cetane number improver has been proposed and tested to be used with diesel fuel as ameans of reducing exhaust emissions. The addition of (2-ethylhexyl nitrate) was designed to raise fuel cetane number to three stages, 50, 52 and 55 compared to the used conventional diesel fuel whose CN was 48.5. The addition of CN improver results in the decre
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The aim of this work is to create a power control system for wind turbines based on fuzzy logic. Three power control loop was considered including: changing the pitch angle of the blade, changing the length of the blade and turning the nacelle. The stochastic law was given for changes and instant inaccurate assessment of wind conditions changes. Two different algorithms were used for fuzzy inference in the control loop, the Mamdani and Larsen algorithms. These two different algorithms are materialized and developed in this study in Matlab-Fuzzy logic toolbox which has been practically implemented using necessary intelligent control system in electrical engineerin
... Show MoreThis research deals with the relationship between television advertising and buying random cosmetics, where we find that TV ads influence on the purchasing behavior of women, has conducted research in the field on a sample of women in the University of Baghdad, was a random sample taken from 150 different women in the age and social levels educational and cultural students and employees and teachers in order to sample representative be for the research community, and designed a questionnaire for this purpose form as a tool to collect data and information search and analyzed they answered the sample surveyed using a statistical program (spss) to extract percentages And correlation coefficients and testing square Kay , The study found Of w
... Show MoreThe objective of this study is to attempt to provide a quantitative analysis to the causes of unemployment in Iraq and its mechanisms of generation, as well as a review of the most important types of both visible and invisible unemployment, and an attempt to measure the disguised unemployment and analyze the causes. The problem of the research lies in the fact that the Iraqi Economy has been suffered for a long time although its characterized by abundant physical and natural resources, from the existence of the phenomenon of unemployment in the previous two types. Causing a lot of economic problems, represented by the great waste of resources and
... Show MoreAbstract:
Viral marketing has become one of the modern strategies adopted by organizations in the marketing of products and services. The idea of viral marketing focuses on the social relations between individuals and groups. As a result of the technological development, most organizations have resorted to using the Internet and its applications and social media to market and promote their products. To reach the largest number of consumers to display their products and services in many ways, including text, audio, visual or video and thus affect the behavior of the consumer.
The problem of the study was the following question (do viral marketing technologies have an impact on consumer behavior?)
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