In this work, enhancement to the fluorescence characteristics of laser dye solutions hosting highly-pure titanium dioxide nanoparticles as random gain media. This was achieved by coating two opposite sides of the cells containing these media with nanostructured thin films of highly-pure titanium dioxide. Two laser dyes; Rhodamine B and Coumarin 102, were used to prepare solutions in hexanol and methanol, respectively, as hosts for the nanoparticles. The nanoparticles and thin films were prepared by dc reactive magnetron sputtering technique. The enhancement was observed by the narrowing of fluorescence linewidth as well as by increasing the fluorescence intensity. These parameters were compared to those of the dye only and the dye solution hosting nanoparticles without coatings on the cell. For Rhodamine B and Coumarin 102 samples, the fluorescence intensity of coated-cell sample was increased by 230, and 351%, respectively, with respect to that of dye only and by 152 and 141%, respectively, with respect to that of uncoated cells. The full-width at half-maximum (FWHM) was determined for both cases and found to be 8 and 9 nm, respectively.
The concept of aesthetics is one of the postmodern propositions, and it is one of the branches of philosophy that examines beauty, its standards and theories, and it is a holistic concept that includes several concepts, including the beautiful, the ugly, and the sublime.
The concept of aesthetics dealt with several studies in general (and in the field of architecture in particular), and the problem of aesthetics is in the blurring of the relationship between aesthetics and architectural criticism, based on the research hypothesis which states that there is a relationship between aesthetics and architectural criticism. The importance of the research in accommodating aesthetic standards and bases of evaluation that increases the possi
The winds of change witnessed by the Ottoman Empire after the constitutional coup in 1908 carried the breezes of freedom, writers and journalists were finally able to express themselves, this change was reflected on intellectual and cultural life and on freedom of publication and expression , perhaps the first thing that was affected by this change was the press, it entered a new phase in which it got rid of those restrictions and limitations imposed by the Ottoman Sultanate concerning the right to issue newspapers and freedom of publication. Iraq was the first to witness a new phase of press relief, before the constitutional coup, it was possible to count on the fingers of the hand how many newspapers were issued, that number doubled to
... Show MoreIn this research, hand lay- up technique is used to prepare samples from epoxy resin reinforced with multi- walled carbon nanotubes in different weight fractions (0, 2, 3, 4, 5) wt%. The immersion effect by sodium hydroxide solution (NaOH) at normality (0.3N) for a period of (15 days) on the thermal conductivity of nanocomposites was studied, and compared to natural condition (before immersion). The thermal conductivity of epoxy nanocomposites specimens were carried out using Lee’s disk method. The experimental results showed that thermal conductivity increased with increase weight fraction before and after immersion for all specimens, while the immersion effect leads to decrease thermal conductive values compared to thermal conductivi
... Show MoreSeven fish species were collected from the drainage network at Al-Madaen region, south of
Baghdad with the aid of a cast net during the period from March to August 1993. These fishes
were infected with 22 parasite species (seven sporozoans, three ciliated protozoans, seven
monogeneans, two nematodes, one acanthocephalan and two crustaceans) and one fungus
species. Among such parasites, Chloromyxum wardi and Cystidicola sp. are reported here for
the first time in Iraq. In addition, 11 new host records are added to the list of parasites of
fishes of Iraq.
The current study aimed to reveal the role of the high school (boys) in the Governorate of Qurayyat (KSA) in promoting intellectual security of students, and whether there were differences in the estimates of the study sample due to the variables; the current position, academic qualification, teaching specialization and years of experience. This study was conducted by applying the analytical descriptive method, and used questionnaire as a tool for data collection. The survey consisted of (44) ite
... Show MoreIn the present study, composites were prepared by Hand lay-up molding and investigated. The composites constituents were epoxy resin as the matrix, 6% volume fractions of Glass Fibers (G.F) as reinforcement and 3%, 6% of industrial powder (Calcium Carbonate CaCO3, Potassium Carbonate K2CO3 and Sodium Carbonate Na2CO3) as filler. Density, water absorption, hardness test, flexural strength, shear stress measurements and tests were conducted to reveal their values for each type of composite material. The results showed that the non – reinforced epoxy have lower properties than composites material. Measured density results had show an incremental increase with volume fraction increase
... Show MoreBackground: Listeria monocytogenes, a member of the genus Listeria, is widely distributed in agricultural environments, such as soil, manure and water. The genus of Listeria bacteria is about 15-17 species. It is a pathogenic bacterium that can cause a rare but dangerous infection called listeriosis.
Objectives: Studying the rate of salads contaminated with Listeria bacteria. and Listeria monocytogenes according to International, Arabic and Iraqi specifications and finding the correlation between commitments of restaurants to standard health conditions with contamination with these bacteria
Methods: The study included
... Show MoreFlow unit and reservoir rock type identification in carbonates are difficult due to the intricacy of pore networks caused by facies changes and diagenetic processes. On the other hand, these classifications of rock type are necessary for understanding a reservoir and predicting its production performance in the face of any activity. The current study focuses on rock type and flow unit classification for the Mishrif reservoir in Iraq's southeast and the study is based on data from five wells that penetrate it. Integration of several methods was used to determine the flow unit based on well log interpretation and petrophysical properties. The flow units were identified using the Quality Index of Rock and the Indicator of Flow Zone. Th
... Show MoreThis research is focusing on finding more effective polymers that leads to enhance the rheological properties of Water Base Muds. The experiments are done for different types of mud for all substances which are Polyacrylamide, Xanthan gum, CMC (Carboxyl Methyl Cellulose). This study shows the effect of add polymer to red bentonite mud, effect of add polymer to Iraqi bentonite mud, the effect of add bentonite to polymer mud. The mud properties of Iraqi bentonite blank are enhanced after adding the polymers to the blank mix, CMC gives the highest value of plastic viscosity and Gel strength than others; X-anthan gives the highest value of yield point and gel strength than others. For the red bentonite mud, Polyacrylamide ha
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