The work includes fabrication of undoped and silver-doped nanostructured nickel oxide in form thin films, which use for applications such as gas sensors. Pulsed-laser deposition (PLD) technique was used to fabricate the films on a glass substrate. The structure of films is studied by using techniques of x-ray diffraction, SEM, and EDX. Thermal annealing was performed on these films at 450°C to introduce its effect on the characteristics of these films. The films were doped with a silver element at different doping levels and both electrical and gas sensing characteristics were studied and compared to those of the undoped films. Reasonable enhancements in these characteristics were observed and attributed to the effects of thermal annealing as well as doping with silver. Gas sensing measurements were carried out using NO2 as a gaseous species to be detected. The results showed that the electrical conductivity, density as well as mobility of charge carriers, and gas sensitivity were affected by the doping level and annealing treatment.
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This study was conducted to describe a protocol for the callus establishing culture of Lavandula angustifolia plant and estimating their content of volatile oil. The quantity of volatile oil callus tissues was compared with that of leaves production. Callus was induced from leaf explants on Murashige and Skoog medium (MS) supplemented with Naphthalene acetic acid (NAA) and Benzyl adenine (BA) in different concentrations. Maximum callus fresh weight was obtained in the combination of 10 mg/L BA and 3 mg/L NAA which reached 18 g after four weeks. The results of this work showed that the quantity of volatile oil from the highest fresh weight callus was 6 ml compared with quantity of 18g of leaves which gave 0.5 ml. Volatile o
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This article examines and proposes a dietary chain model with a prey shelter and alternative food sources. It is anticipated that mid-predators' availability is positively correlated with the number of refuges. The solution's existence and exclusivity are examined. It is established that the solution is bounded. It is explored whether all potential equilibrium points exist and are locally stable. The Lyapunov approach is used to investigate the equilibrium points' worldwide stability. Utilizing a Sotomayor theorem application, local bifurcation is studied. Numerical simulation is used to better comprehend the dynamics of the model and define the control set of parameters.
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The electrospun nanofibers membranes (ENMs) have gained great attention due to their superior performance. However, the low mechanical strength of ENMs, such as the rigidity and low strength, limits their applications in many aspects which need adequate strength, such as water filtration. This work investigates the impact of electrospinning parameters on the properties of ENMs fabricated from polyacrylonitrile (PAN) solved in N, N-Dimethylformamide (DMF). The studied electrospinning parameters were polymer concentration, solution flow rate, collector rotating speed, and the distance between the needle and collector. The fabricated ENMs were characterized using scanning electron microscopy (SEM) to understand the surface morphology and es
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The aim of this study is to get practical evidence from the Egyptian business environment The Impact of Audit Committees Effectiveness and External Audit Quality on Timeliness of annual Financial Report. Design and methodology: The study based on the content analysis technique to examine the annual reports of a sample of (30) companies listed on the Egyptian Stock Exchange (EGX100) during the period (2016-2019) with a total of (120) respondents. To test the research hypotheses, the results of the study indicate that there is a negative significant impact of audit committees on timeliness of annual financial report. Moreover, while there is a negative impact on the quality of the external audit on the timing of issuing the annual
... Show MorePaul Auster's City of Glass is here singled out as representative of the writer's The New
York Trilogy. All throughout his novelistic career, Auster has been working on a pseudothesis
that adheres to a certain aesthetic of disappearance. The study engages this Austerian
aesthetic apropos of certain theoretical stretches such as the Emersonian "Not Me", the
Thoreauvian "interval" or "nowhere", the Deleuzian "nomadic trajectory", the Derridian
"grammè" or "specter", and the Baudrillardian "disappearance". The city of the novel's titling
is here seen as the trope of all that which has already disappeared, and hence it is seen as the
space (mise en scène) where the perfect crime of the murder of the real is to be thoro
Leishmania causes disease ranging from self-healing cutaneous to fatal visceral leishmaniasis (VL). Leishmaniasis is reported endemic in 88 countries, including Iraq, in which 82% in low-income countries. The diseases develop following the bite of sand flies injecting Leishmania promastigotes into skin. Promastigotes transform into amastigotes in vivo multiplying within macrophages. In this study we have investigated the ability of axenic procyclic promastigotes of cutaneous Leishmania tropica and visceral Leishmania donovani survive in M199 media with or without Fetal Bovine Serum (FBS) added. Three time incubation periods were adopted (24, 48 and 72) hours and the results showed that L. tropica was able to survive and multiply in both
... Show MoreSewer system plays an essential task in urban cities by protecting public health and the environment. The operation, maintenance, and rehabilitation of this network have to be sustainable and scientifically. For this purpose, it is crucial to support operators, decision makers and municipalities with performance evaluation procedure that is based on operational factors. In this paper, serviceability and performance indicator (PI) principles are employed to propose methodology comprising two enhanced PI curves that can be used to evaluate the individual sewers depending on operational factors such as flowing velocity and wastewater level in the sewers. To test this methodology; a case study of al-Rusafa in Baghdad city is
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