A random laser is a non-conventional laser whose feedback mechanism is based on dissorder-induced light. However, random lasers occur in gain media with numerous scatterers and produce coherent laser emission without any predesigned cavity. The generation of coherent emission from multiple scattering is quite general and its basic principles are shown here using sulforhodamine B-TiO suspensions system. These suspensions were pumped with 337.1 nm pulses from N2 laser and the spectral and temporal behavior of light emitted from the pumped surface was recorded. When we pump power above a certain threshold a dramatic narrowing of the emission line width and a shortening of the emitted pulses were observed. We have experimentally found that in a random laser based scattering, the threshold pumping density decreases with pump energy increased.
Ferric oxide nanoparticles Fe3O4NPs have been prepared by the coprecipitation method, which were used to functionalize the surface of electrospun nanofibers of polyacrylonitrile to increase their effectiveness in adsorption of Congo red (CR) dye from their aqueous solutions. The effect factors of adsorption were systematically investigated such as adsorbent mass, initial concentration, contact time, temperature, ionic strength and pH. The maximum adsorbed amount of the dye was at 0.003g of adsorbent. The adsorption of dye increased with increasing initial dye concentration and the system reaches to the equilibrium state at 150 min. The adsorbed dye capacity decreases with increasing temperature which indicates to the exothermic nature of ad
... Show MoreDiazotization reaction between 1-(2,4,6-Trihydroxy-phenyl)-ethanone and diazonium salts was carried out resulting in ligand 4-(3-Acetyl-2,4,6-trihydroxy-phenylazo)-N-(5-methyl-isoxazol-3-yl)-benzenesulfonamide, this in turn reacted with the next metal ions (V4+ , Cr3+ , Mn2+ and Cu2+) forming stable complexes with unique geometries such as (Octahedral for both Cr3+ , Mn2+ and Cu2+ ,squar pyramidal for V4+). The creation of such complexes was detected by employing spectroscopic means involving ultraviolet-visible which proved the obtained geometries, fourier transfer proved the formation of azo group and and the coordination with metal ion through it. Pyrolysis (TGA & DSC) studies proved the coordination of water residues with me
... Show MoreThe Study aims at evaluating the efficiency of the regional transportation net in Al-mahmoodiya Qadaa center. The bus station of the Qadaa center is suffering from heavy traffic jam, which is due to the ongoing movement of the adjacent provinces, particularly the small cities. They vary in the degree of their link by the regional transportation net that links the province with the centers of big cities. That affects the traffic flow of the civilians of these cities and their daily activities in hierarchical way To achieve the purpose of the study, a questionnaire has been constructed to collect data through selecting a random sample including the passengers who are coming to the bus station in Al-Mahmoodiya center to know the flo
... Show MoreGiven the paucity and toxicity of available drugs for leishmaniasis, coupled with the advent of drug resistance, the discovery of new therapies for this neglected tropical disease is recognised as being of the utmost urgency. As such antimicrobial peptides (AMPs) have been proposed as promising compounds against the causative Leishmania species, insect vector-borne protozoan parasites. Here the AMP temporins A, B and 1Sa have been synthesised and screened for activity against Leishmania mexicana insect stage promastigotes and mammalian stage amastigotes, a significant cause of human cutaneous disease. In contrast to previous studies with other species the activity of these AMPs against L. mexicana amastigotes was low. This suggests that ama
... Show MoreToxoplasma gondii is an opportunistic parasite in immune-compromised persons. The prevalence of toxoplasmosis in psoriasis patients is investigated. In addition, the treatment effect on psoriasis patients infected with toxoplasmosis through evaluating Tumor Necrosis Factor-α (TNF-α) cytokine levels is studied. Blood samples were collected from 130 individuals who involved 60 control samples and 70 samples with psoriasis. They attended Medical City Hospital in Baghdad province from October 2017 - February 2018. Then, the anti- T. gondii antibodies (IgM and IgG) and TNF- α in the sera were determined via the enzyme linked immune-sorbent assay. The highe
... Show MoreA Field experiment was conducted in Horticulture and Landscape Department, College of Agricultural Engineering Sciences, University of Baghdad, Al-Jadriah during fall 2019-2020 to study changes in the growth and yield of broccoli grown in the alternative solution ABEER, affected by gas enrichment and spraying with coconut water and moringa aqueous extract under the hydroponic cultivation system. Nested design with three replications adopted in the experiment, each of them included in main plot the first factor, which is gas enrichment (O2 and O3), Then levels of second factor were randomly distributed within each replicate, which included spra
The effects of scattering and secondary radiation generated inside the material on dose equivalent rate where studied using Co60 and Cs137 sources of activity (199.8 , 177.6) MBq , respectively for different thicknesses of Al , Pb and Pb- glass . The results showed that the equivalent rate increases when the effect of scattering was included for Al and Pb shields with cobalt-60 source of energy 1.25 MeV ; and decreases for Pb shield with Cs-137 source of energy 0.662MeV .The results showed also that the atomic number of The material effects the dose equivalent rate . The Pb-glass shield was found to be more efficient in absorption than other shields.
The purpose of this study is to investigate learners' listening comprehension problems with Englishlectures. The study was guided by research question (What are the listening comprehension problems learners have with lectures in English).Furthermore; the main significant goal were declared through conducting this study, as well as providing some procedures of distribution the questionnaire of the study.Moreover, it presents several definitions of listening. This study definitely depends on questionnaire instrument to gathering the required data. The participants of the study were 30 learners completed their secondary school and joined at the college. Based on the findings among the five factors (text, speaker, task, environment, and list
... Show MoreSpin coating technique has been applied in this work to prepared Xerogel films doped with Rhodamine 6G laser dyes. The solid host of laser dye modifies its spectroscopic properties with respect to liquid host. During the spin coating process the dye molecules suffer from changing their environment. The effects of three parameters were studied here: the spinning speed, multilayer coating and formaldehyde addition