Light is an important factor that influences the growth and photosynthetic efficiency of microalgae; however, little is known about how light intensity together with the wavelength affect the photosynthetic capacity and growth of marine microalgae. In the present study, the growth of the marine green microalga Dunaliella parva was studied and optimized under different light intensities (25 ~ 70 μmol m-2 s-1) and qualities (blue, green, and red) in comparison with white light at 40 μmol m-2 s-1 as a control. The growth was monitored by counting the cell number, pigment content, Chl a, Chl b, and carotenoids concentrations. The optimal growth and highest photosynthetic efficiency (Fv/Fm) were recorded at a light intensity of 40 μ mol m-2 s-1, white light, and 1.25 M NaCl (1.47 and 0.678×106 cell mL-1, respectively). The activity of antioxidant enzymes, including catalase and peroxidase, as well as ascorbate content, showed the highest values of 0.190 µM/min.mg Chl, 0.434 and 13.3 mg/g f.wt. respectively, under the green light, which confirmed the presence of environmental stresses.
Nanoparticles have gained considerable interest in recent times for oil recovery purposes owing to significant capabilities in wettability alteration of reservoir rocks. Wettability is a key factor controlling displacement efficiency and ultimate recovery of oil. The present study investigates the influence of zirconium (IV) oxide (ZrO2) and nickel (II) oxide (NiO) nanoparticles on the wetting preference of fractured (oil-wet) limestone formations. Wettability was assessed through SEM, AFM and contact angle. The potentials of the nanoparticles to alter oil-wet calcite substrates water wet, was experimentally tested at low nanoparticle concentrations (0.004–0.05 wt%). Quite similar behaviour was observed for both nanoparticles at the same
... Show MoreResearch Summary
It highlights the importance of assessing the demand for money function in Iraq through the understanding of the relationship between him and affecting the variables by searching the stability of this function and the extent of their influence in the Iraqi dinar exchange rate in order to know the amount of their contribution to the monetary policies of the Iraqi economy fee, as well as through study behavior of the demand for money function in Iraq and analyze the determinants of the demand for money for the period 1991-2013 and the impact of these determinants in the demand for money in Iraq.
And that the problem that we face is how to estimate the total demand for money in
... Show MoreThe present research included synthesis of silver nanoparticle from(1*10-3,1*10-4 and1*10-5) M aqueous AgNO3 solution through the extract of M.parviflora reducing agent. In the process of synthesizing silver nanoparticles we detected a rapid reduction of silver ions leading to the formation of stable crystalline silver nanoparticles in the solution.
The aim of the research is to investigate potential effects of the finance industry and block-chain to general business of financing in particular, as well as its shortcomings and difficulties. To answer the research questions, the researcher used the objective narrative-analytical descriptive approach and included a qualitative analysis of Blockchain technology. The process of Blockchain technology based on their industries, the authors were selected based on their reputation in the Blockchain field. The research found that Blockchain can improve the efficiency of the banking industry's various sections. It has the ability to upgrade and transfer wages across borders, financial reporting and compliance, as well as trade finance
... Show MoreThis research aims the effects of negative media on the educational identity of community. Whereas display the concept of educational identity and its basic components, as well as the role of educational institutions for example the school and the family in form it and reinforcing this identity to individuals. The study showcasing the harmful impact of both traditional and modern media on identity and values, spotlight several examples like the promotion of consumerism and materialism through television programs. which results in the young people to adopt materialistic values like simplicity. The study concludes that media is a double-edged weapon: it can instill virtues and support education if used duly, but it can also weaken the educat
... Show MoreA field study aimed to improve administrative performance of the Heads of Departments in Wasit University in light of the administrative functions, a questionnaire constructed was c of 38 items, as have been applied during the academic year 2014/2015 to a group of experts from the deans and assistants, professors and heads of departments using the Delphi method by two rounds the adoption rate of 90% and an agreement was numbered 30 experts and study reached important results have been analyzed and discussed according to fields of study, a planning, organization and direction.
Asphalt binder is a thermoplastic material that conducts as an elastic solid at lower service temperatures or throughout fast loading rate. At a high temperature or slow rate of loading, asphalt binder conducts as a different liquid. The classical duplication generates a required to assess the mechanical properties of asphalt concrete at the anticipated service temperature to reduce the stress cracking, which happens at lower temperatures, fatigue, and the plastic deformation at higher temperatures (rutting). In this study, an achievement was made to assess the effect of temperature on the mechanical characteristics of asphalt concrete mixes. A total of 132 asphalt concrete samples were attended utilizing two asphalt cement grades (40-50) a
... Show MoreAsphalt pavement properties in Iraq are highly affected by elevated summer air temperatures. One of these properties is stiffness (resilient modulus). To explain the effect of air temperatures on stiffness of asphalt concrete, it is necessary to determine the distribution of temperatures through the pavement asphalt concrete layers. In this study, the distribution of pavement temperatures at three depths (2cm,7cm, 10cm) below the pavement surface is determined by using the temperature data logger instrument. A relationship for determining pavement temperature as related to depth and air temperature has been suggested. To achieve the objective of this thesis, the prepared specimens have been tested for indirect tension in accordance with
... Show MorePorous silicon (P-Si) has been produced in this work by photoelectrochemical (PEC) etching process. The irradiation has been achieved using diode laser of (2 W) power and 810 nm wavelength. The influence of various irradiation times on the properties of P-Si material such as P-Si layer thickness, surface aspect, pore diameter and the thickness of walls between pores as well as porosity and etching rate was investigated by depending on the scanning electron micrograph (SEM) technique and gravimetric measurements.
The research discusses two variables are important, orientation marketing and quality of service, and that the purpose of the research is to see whether the telecom companies applied orientation marketing or not and to what extent is keen to apply it to suit the Iraqi environment as it has been applied research in kork Telecom company and Asia Cell Telecom are sectors service job in the business sector in Iraq, The information was obtained through the design of the questionnaire compatible runway Likert, and distribution (92) questionnaire, which (50) for the company Korek Telecom and (42) of the Asia-Cell, research population sample included a number of staff in the departments and units in the two companies, it has been support
... Show More