In the present work, the pollutants of the municipal wastewater are reduced using Chlorella vulgaris microalgae. The pollutants that were treated are: Total organic carbon (TOC), Chemical oxygen demand (COD), Nitrate (NO3), and Phosphate (PO4). Firstly, the treatment was achieved at atmospheric conditions (Temperature = 25oC), pH 7 with time (1 – 48 h). To study the effect of other microorganisms on the reduction of pollutants, sterilized wastewater and unsterilized wastewater were used for two types of packing (cylindrical plastic and cubic polystyrene) as well as algae's broth (without packing), where the microalgae are grown on the packing then transported to the wastewater for treatment. The results showed that the other microorganism in unsterilized wastewater can slightly contribute in the treatment. Packing of cylindrical plastic is more effective than the cubic polystyrene, and microalgae's broth gives better results than the two types of packing. The treatment in the first hours was performed quickly while in the last hours, it was very slow. Then, the following parameters in the range of (temperature: 20 – 35o) pH (5 – 8), volume ratio of wastewater to microalgae's broth (1 – 2.5) were studied for sterilized wastewater and constant treatment time equal to 48 h. The results showed that the maximum reduction of pollutants are: TOC = 92.3%, NO3 = 65.2%, PO4 = 93.2% at T = 35oC, pH 8, and (wastewater/algae broth) ratio = 1, and COD = 85.6% at T = 30oC, pH 7, and (wastewater/ algae broth) ratio = 1. The temperature and pH have little effect on the reduction of pollutants compared with the wastewater/algae broth ratio. The adsorption isotherm for pollutant was also studied for three types of isotherm; linear, Freundlich, and Langmuir. The results showed that the treated pollutants are the Langmiur adsorption isotherm.
The study aimed to clarify the meanings learned and inferred from reading books، letters and messages in Surat Al-Qur’an. The inductive method، the analytical method، and the deductive method، One of the most prominent results of the research: that the multiplicity of Qur’anic readings produces a variety and expansion in the meaning that has a clear impact on the interpretation by clarifying the meaning of the verse.
In this paper, compared eight methods for generating the initial value and the impact of these methods to estimate the parameter of a autoregressive model, as was the use of three of the most popular methods to estimate the model and the most commonly used by researchers MLL method, Barg method and the least squares method and that using the method of simulation model first order autoregressive through the design of a number of simulation experiments and the different sizes of the samples.
The logistic regression model is an important statistical model showing the relationship between the binary variable and the explanatory variables. The large number of explanations that are usually used to illustrate the response led to the emergence of the problem of linear multiplicity between the explanatory variables that make estimating the parameters of the model not accurate.
... Show MoreThe subject of the evolution of fire insurance of the hottest topics accidents, because it falls within the commercial insurance, as its importance is reflected for being a security source and contentment of the insured person and so it is worth pointing out the importance of fire insurance in enterprises and organizations of all kinds, because of the guarantee of its assets from meridian as well as protection from the effects of the fire therefore ensure continuity in the performance of their activities
At the beginning of the nineties increased responsibility of the auditor to the community as the demand for auditing the environmental performance for the economic units in addition to audit the financial performance. With the aim of preserving the environment and reducing the damagse as aresult of the negative effects of the activities of these units.
The researh deal with two sides the first one identifies the theoretical framework of the concept of environmental audits, requirements, methods, types of procedures, and duties of the auditor in conducting environmental audits. It also deals with the concept of the enviro
... Show MoreThe research aims to shed light on the impact of the application of the electronic services system on electronic banking activities in a sample of Iraqi banks, as investment in technology is the most important factor for the success and future growth of administrative companies in general, and banking in particular, as global economic developments in the field of Technology has led the majority of banking sectors in the world to undergo deep reforms and radical changes in the entity of their systems and mechanisms to confront competition and keep pace with economic changes, as the concept of banking services and its diversity changed with it, especially since persistence in the traditional approach no longer gi
... Show MoreBiotreatment using immobilized cells (IC) technology has proved to be the most promising and most economical approach for the removal of many toxic organic pollutants found in petroleum-refinery wastewater (PRW) such as phenol. This study was undertaken to evaluate the degradation of phenol by Pseudomonas cells individually immobilized in two different bio-carrier matrices including polyvinyl alcohol-guar gum (PVA-GG) and polyvinyl alcohol-agar agar (PVA-AA). Results of batch experiments revealed that complete removal of phenol was attained in the first cycle after 150 min using immobilized cells (IC) in both PVA-GG and PVA-AA. Additional cycles were confirmed to evaluate the validity of recycling beads of immob
... Show Morethe research was exposed to a study the importance of the role of the supportive entities in providing the useful information to the tax administration and their ability to extend the level of the tax base of taxpayers, through the improvement of the tax payers determination and their tax settle for the purpose of increasing the tax revenue, and shed light on the legal evidence through which these entities become officially assigned to perform a supplementary task to the General Committee for Taxes GCT, to help it to perform its task efficiently, and to study the reasons of the weak cooperation of the supportive entities and their reluctance to provide useful information which leads to limiting the tax base.
The research data hav
... Show MoreThere are many studies that discussed the famous museum's graveyards in the Islamic worlds, to study the lives of these figures, there are many difficulties for their studies because the first we need the regularity and history information, and many sciences support, such as in language, geography information.
I am studying the research from Maraqid Al-Maaraf book by Harz Aldeen, the book has large members about the persons have graved in Persian Country in the middle ages, there are more than (30) figures in my study, I have studied every figure in this research depending on the sources and references books.
Malaysia will be an ageing population by 2030 as the number of those aged 60 years and above has increased drastically from 6.2 percent in 2000 and is expected to reach 13.6 percent by 2030. There are many challenges that will be faced due to the ageing population, one of which is the increasing cost of pensions in the future. In view of that, it is necessary to investigate the effect of actuarial assumptions on pension liabilities under the perspective of ageing. To estimate the pension liabilities, the Projected Unit Credit method is used in the study and commutation functions are employed in the process. Demographic risk and salary risk have been identified as major risks in analyzing pension liabilities in this study. The sensitivity
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