In this study, low cost biosorbent ̶inactive biomass (IB) granules (dp=0.433mm) taken from drying beds of Al-Rustomia Wastewater Treatment Plant, Baghdad-Iraq were used for investigating the optimum conditions of Pb(II), Cu(II), and Ni(II) biosorption from aqueous solutions. Various physico-chemical parameters such as initial metal ion concentration (50 to 200 mg/l), equilibrium time (0-180 min), pH (2-9), agitation speed (50-200 rpm), particles size (0.433 mm), and adsorbent dosage (0.05-1 g/100 ml) were studied. Six mathematical models describing the biosorption equilibrium and isotherm constants were tested to find the maximum uptake capacities: Langmuir, Freundlich, Redlich–Peterson, Sips, Khan, and Toth models. The best fit to the Pb(II) and Ni(II) biosorption results was obtained by Langmuir model with maximum uptake capacities of 52.76 and 36.97 mg/g for these two ions respectively. While for Cu(II) the corresponding value was 38.07 mg/g obtained with Khan model. The kinetic study demonstrated that the optimum agitation speed was 400 rpm, at which the best removal efficiency and/or minimum surface mass transfer resistance (MSMTR) was achieved. A pseudosecond-order rate kinetic model gave the best fit to the experimental data (R 2 = 0.99), resulting in mass transfer coefficient values of 42.84×10−5, 1.57×10−5 , and 2.85×10−5 m/s for Pb(II), Cu(II), and Ni(II) respectively. The thermodynamic study showed that the biosorption process was spontaneous and exothermic in nature.
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This paper presents an experimental study for strengthening existing columns against axial compressive loads. The objective of this work is to study the behavior of concrete square columns strengthening with circulation technique. In Iraq, there are significantly more reinforced rectangular and square columns than reinforced circular columns in reinforced concrete buildings. Moreover, early research studies indicated that strengthening of rectangular or square columns using wraps of CFRP (Carbon Fiber Reinforced Polymer) provided rather little enhancement to their load-carrying capacity. In this paper, shape modification technique was performed to modify the shape (cross section) of the columns from square columns into circular colu
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Concrete columns with hollow-core sections find widespread application owing to their excellent structural efficiency and efficient material utilization. However, corrosion poses a challenge in concrete buildings with steel reinforcement. This paper explores the possibility of using glass fiber-reinforced polymer (GFRP) reinforcement as a non-corrosive and economically viable substitute for steel reinforcement in short square hollow concrete columns. Twelve hollow short columns were meticulously prepared in the laboratory experiments and subjected to pure axial compressive loads until failure. All columns featured a hollow square section with exterior dimensions of (180 × 180) mm and 900 mm height. The columns were categorized into
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Public service motivation in public service organisations is one of the main problems that many developing countries have begun to experience, including Iraq. The public agenda is increasingly complex with reduced financial resources. In addition, these organisations have increased responsibilities with respect to the achievement of public goals and objectives as they are responsible for providing key services to members of the community (education, health and social work). This research is based on the degree of public service motivation among those working in health education and social work in public organisations, and aims to show the extent of the difference in the public service motivation of these employees according to di
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This paper deals with the Magnetohydrodynyamic (Mill)) flow for a viscoclastic fluid of the generalized Oldroyd-B model. The fractional calculus approach is used to establish the constitutive relationship of the non-Newtonian fluid model. Exact analytic solutions for the velocity and shear stress fields in terms of the Fox H-function are obtained by using discrete Laplace transform. The effect of different parameter that controlled the motion and shear stress equations are studied through plotting using the MATHEMATICA-8 software.
The present study attempts to examine verbal/nonverbal impoliteness in the classroom interaction and outside it in one of the movies, namely, The Marva Collins. Impoliteness, which is significantly studied within pragmatics, is a negative attitude towards particular behaviors. It always presumes to have emotional concerns for at least one participant who has caused it. This study is an attempt to examine verbal/nonverbal impoliteness in The Marva Collins movie. The study aims to investigate the different types of impoliteness strategies used in the four selected scenes and find out whether the speaker’s status has anything to do with the types of impoliteness. Besides, the functions performed are also examined by following a qual
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The substantial key to initiate an explicit statistical formula for a physically specified continua is to consider a derivative expression, in order to identify the definitive configuration of the continua itself. Moreover, this statistical formula is to reflect the whole distribution of the formula of which the considered continua is the most likely to be dependent. However, a somewhat mathematically and physically tedious path to arrive at the required statistical formula is needed. The procedure in the present research is to establish, modify, and implement an optimized amalgamation between Airy stress function for elastically-deformed media and the multi-canonical joint probability density functions for multivariate distribution complet
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Lying is a controversial issue as it is closely related to one's intended meaning to achieve certain pragmatic functions. The use of lying in literary works is closely related to the characters’ pragmatic functions as in the case of Miller's The Crucible where it is used as a deceptive complex phenomenon that cannot be observed out of context. That is, the use of lying as a deceptive phenomenon represents a violation to Grices's Maxims. Thus, the study aims to qualitatively examine the kinds of maxims being violated, the kinds of violations conducted, the strategies followed in the violations, and the pragmatic functions behind such violations across the different categories of lies. To this end, the (30) extracts fou
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