Previously, many empirical models have been used to predict corrosion rates under different CO2 corrosion parameters conditions. Most of these models did not predict the corrosion rate exactly, besides it determined effects of variables by holding some variables constant and changing the values of other variables to obtain the regression model. As a result the experiments will be large and cost too much. In this paper response surface methodology (RSM) was proposed to optimize the experiments and reduce the experimental running. The experiments studied effects of temperature (40 – 60 °C), pH (3-5), acetic acid (HAc) concentration (1000-3000 ppm) and rotation speed (1000-1500 rpm) on CO2 corrosion performance of the regression model calculated by RSM. The experiments were conducted in saturated solution of CO2 with 3.5 % NaCl solution. STATISTICA program version 10 was used for data analysis. In conclusion a quadratic model is proposed to predict the effect of mentioned variables in CO2 environment.

Objectives: The study aims to: (1) assess psychological distress in parents of autistic children, (2) identify the
relationship between psychological distress and parents' socio-demographic characteristics such as (age, marital
status, relationship with child, educational level and monthly income) and (3) identify the relationship between
parent's distress and some of children' socio-demographic characteristics such as (gender, age, birth order and
mean number of children).
Methodology: A descriptive–analytical study that was carried out from December 12th, 2011 to May 1st, 2012.
on a purposive (non- probability) sample of 120 parents (father and mother) who have children with autism and
send their children to the
This research aims to study and reveal the influence of Bauhaus principles in contemporary graphic design. The researcher determined the objective/spatial/temporal limit: Study of the Bauhaus influence in the design of the graphic poster in Germany in 2020. The theoretical framework in the first section dealt with (the emergence and factors of the emergence of the Bauhaus school and its characteristics), while the second topic dealt with (the intellectual, functional and aesthetic data of the Bauhaus School), after which the indicators that resulted from the theoretical framework were produced.
He mentioned four previous studies, one of them was discussed in detail. In the third chapter he defined the methodology, society, and sam
... Show MoreThe aim of the research to measure the correlation relationship between modern manufacturing systems and process design and measure the effect by adopting the regression; the research consists of two main variables, which are modern manufacturing systems and process design; it was applied in the production lines of the General Company for Construction Industries, There is a sample of managers, engineers, technicians, administrators, and some workers were selected to fill the special questionnaire with (70) forms which distributed and (65) were approved suitable for use, For data analysis the correlation coefficient was adopted to measure the relationship and regression analysis to find out the effect, Using (SPSS), So the first h
... Show MoreIn this paper we study the selection of cognitive elements and criteria of the inflectional structure of the Russian and Arabic languages in the process of speech communication. Phonetic-physiological principle is the main parameter by which the elements and criteria of cognitive activity in the presented study are distinguished. On the basis of the above mentioned parameter, we select the investigated criteria and elements. The first criterion is semantic, reflects the accordance of the elements of thinking to sound combinations in the studied languages, and allows us to distinguish the second criterion – morphonological. The second criterion depends on the phonetic changes of these combinations occurring in the process of speech activit
... Show MoreStable isotope composition of δ2H and δ18O was investigated in the water resources of the Shwan sub-Basin northeast of Iraq. The study objects conceived the possible factors that affect the stable isotopes’ composition in precipitation additionally to achieve information concerning recharge processes and estimate the groundwater recharge sources. In this study, four precipitation samples were collected at the study area for the 2020–2021 hydrological year. Thirty-two groundwater samples and one surface water sample from Lesser Zab River (LZR) were collected during the same period for two sampling seasons. The results of observed meteorological data show a very small amount of pr
Fusobacterium are compulsory anaerobic gram-negative bacteria, long thin with pointed ends, it causes several illnesses to humans like pocket lesion gingivitis and periodontal disease; therefore our study is constructed on molecular identification and detection of the fadA gene which is responsible for bacterial biofilm formation. In this study, 10.2% Fusobacterium spp. were isolated from pocket lesion gingivitis. The isolates underwent identification depending on several tests under anaerobic conditions and biochemical reactions. All isolates were sensitive to Imipenem (IPM10) 42.7mm/disk, Ciprofloxacin (CIP10) 27.2mm/disk and Erythromycin (E15) 25mm/disk, respectively. 100% of
Leishmania parasites reproduce wherever there are cells of the mononuclear phagocyte system, almost in macrophages. These are most copious in the liver and spleen;therefore, infection leads to an expansion of both of them. This study determined the burden of visceral leishmaniasis (VL) infection on liver and spleen. A total of 20 mice were infected peritoneally with 2x107promastigotes of Leishmania donovani / ml and other 12 mice left without infection as a healthy control. The weight of whole body, liver and spleen were measured and the histological development using hematoxylin and eosin stains were determined after 15, 30, 45-and 60-days post infection. The results represent that the mean weights of liver and spleen were increased in inf
... Show More