This paper investigated the treatment of textile wastewater polluted with aniline blue (AB) by electrocoagulation process using stainless steel mesh electrodes with a horizontal arrangement. The experimental design involved the application of the response surface methodology (RSM) to find the mathematical model, by adjusting the current density (4-20 mA/cm2), distance between electrodes (0.5-3 cm), salt concentration (50-600 mg/l), initial dye concentration (50-250 mg/l), pH value (2-12 ) and experimental time (5-20 min). The results showed that time is the most important parameter affecting the performance of the electrocoagulation system. Maximum removal efficiency (96 %) was obtained at a current density of 20 mA/cm2, distance between electrodes of 1.75 cm, salt concentration of 462.5 mg/l, dye concentration of 50 ppm, pH value of 7, and time duration of 15 min. On the other hand, the electrocoagulation efficiency was directly proportional to current density, salt concentration, and contact time, while it was inversely proportional to dye concentration. Isotherm experiments showed that the equilibrium data are best fitted to Freundlich isotherm and sips isotherm; whereas the kinetics results showed that the rate of adsorption followed the pseudo-second-order with an R2 value of 98 %.
Use of lower squares and restricted boxes
In the estimation of the first-order self-regression parameter
AR (1) (simulation study)
Polyvinyl chloride (PVC) finds use in various industries due to its versatility but is not thermostable, serving as a barrier to causing degradation and release of hydrochloric acid (HCl) under heat stress conditions. Lead and organotin compounds have traditionally been used for stabilizer purpose to discourage such degradation but pose serious ecological as well as health risks. As a counter measure, bio-based stabilizers from plant oils have become popular as a green and sustainable alternative. This review looks back at recent developments in plant oil-based stabilizers for PVC, focusing on the mechanisms of stabilization, sustainability, and cost-effectiveness. We review plant oils such as tung oil, castor oil, and soybean oil,
... Show MoreThe interest in pre-service teacher training has become influential in teaching English as a foreign language, and the purpose of this training course is to prepare qualified teachers to teach effectively through the application of this technique by undergraduate students. This research aims to find out the effect of using the seven principles of good practice as a teaching technique on the fourth stage student-teachers’ performance at the College of Education for Women/University of Baghdad, during the academic year 2017-2018. The sample includes (60) students selected according to the stratified sampling method. The observational checklist used by the department to assess the student teachers’ performance during the practicum perio
... Show MoreWhen the guard honey bees, Apis mellifera L., form a clump at the hive entrance or on the flight board, the oriental hornet, Vespa orientails L., either creeps toward the clump or hovers over it in order to take a bee. Once the hornet creeps, only few bees facing the hornet become alert, rock their heads and antennae, open their wings, and take a posture of defense. The rest of the clump stays listless without any signal of concern. However, the clump stays dense and the defending bees do not detach themselves neither from the rest of the clump nor from each other. For this reason, it is very difficult for the hornet to grab a bee unless the latter makes a “mistake” by detaching herself from other adjacent bees. If the hornet grabs s
... Show More The current research aims to highlight the role of human resource management with its practices (human resource planning, selection and placement, training and development, performance evaluation, compensation, and incentives) in raising the level of individuals' performance and its dimensions (task performance, contextual performance, unproductive work behavior, and adaptive performance) by explaining the research problem, which can be limited to the low level of performance of individuals, where the researchers use the descriptive analytical approach and the SPSS program in the practical aspect of the research community represented by the general manager and his assistant
The aim of this paper is to prove a theorem on the Riesz means of expansions with respect to Riesz bases, which extends the previous results of [1] and [2] on the Schrödinger operator and the ordinary differential operator of 4-th order to the operator of order 2m by using the eigen functions of the ordinary differential operator. Some Symbols that used in the paper: the uniform norm. <,> the inner product in L2. G the set of all boundary elements of G. ˆ u the dual function of u.
The current study aims to investigate the effect of (SWOM) strategy on acquiring the psychological concepts of educational psychology course and its retention among education college students. To do this, a sample of (57) male and female student were intentionally selected from first grade, Kurdish department / college of education / Ibin Rushd of human sciences. The sample distributed on two classes, whereby the experimental group consisted of (28) student were taught according to the (SWOM) strategy while the control group made up of (29) student were taught based on the tradition method. The two researchers designed a scale included (50) item to measure students' achievement. The experiment lasted for ten weeks, SPSS was used
... Show MoreThe survey showed sample opinions of officials in the general company for vegetable oils industry, and the statement of the order of the effect of these dimensions depending on the degree of importance, the questionnaire was used as a key tool in collecting data and information of the sample consisted of 30 officials, arithmetic mean, standard deviation, percentages, Spearman correlation coefficient and the global statistical analysis as a statistical methods that based on statistical program (SPSS), The researcher came to several conclusions, most important that there is high agreement by the respondents of the importance of the dimensions of building a mental picture of the company and to attract the consumer's attention, Also research
... Show MoreThe use of the Iraqi song in the symphony orchestra is one of the pioneering and important works, which carries with it an artistic value of aesthetic specificity in how to use the Iraqi singing heritage. The research aimed to identify the employment of the song (Foug Al-Nakhl) and its works within the Iraqi national symphony orchestra music by the author Hans Count Momer whose works still have a great influence on the authors of the Iraqi orchestra. The researcher presented a brief introduction to the Iraqi Symphony Orchestra, a brief introduction about the author, and the trends of world music towards heritage. He also talked about musical composition, research procedures and tools, and applying the tool to the selected sample (F
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