Abstract : A research was conducted to study the process parameters affecting hexavalent chromium Cr (VI) (carcinogenic compound) the removal percentage from the electrical industries company waste water that contain 88 mg/l of Cr (VI) concentration by adsorption onto tea wastes. Synthetic water with 88 mg/l Cr (VI) concentration was used. Several operation parameters affecting Cr (VI) removal efficiency were investigated, such as pH, initial Cr (VI) concentration, stirring time and tea wastes dose. The experimental results reveal that maximum Cr (VI) removal reached up to 94.26% at pH of 2, stirring time of 180 minute, tea wastes dose of 8gm/100 ml and the equilibrium was attained at 180 minute. Langmuir and Freundlich adsorption isotherm models were analyzed and the experimental results fit very well with Freundlich model.
The present research aims to identify thecorrelation between cognitive motivation andthe trend towards the teaching profession among students of the Department of Chemistry in theFaculty of Education for Pure Sciences - Ibn al-Haytham, as well as to identify the differences in the relationship according to the variable type (male, female). The measures of cognitive motivation and the trend towards the teaching profession were applied, using pearson's correlation coefficient,t-testfor one sample, andthe t-test of two separate samples.
Abstract :
The research aims to diagnose some of the negative phenomena
( Counterfiting , Pettifogging , Embezzlement ) that have been detected over the past ( 2010 – 2014 ), a fixed-term part of the national strategy for the fight against corruption launched by the Joint Council for the fight against corruption in Iraq and measuring the application of government control according to the American standard GAO standards and identifying the potential for the application of those standards gap. It has been collecting data and information of special issues of corruption reports and meeting with (42) employees and the use of a checklist has been prepared for thi
The continued acceleration in the business environment has led to the need for organizations great attention to quality applied in organizations to meet the needs of customers and stay in the market for as long as possible.
Search launched from the underlying problem is the presence of concentrations of defects and waste plaguing the company and to achieve the goal of the study detects the level of quality applied in the factory vessels and reservoirs of the General Company for Heavy Engineering Equipment, As well as calculate wastage rates occurring in the production process and find a relationship between the level of quality and ratios defective in each type of waste, it has been used quantitative meas
... Show MoreThis study identifies the contribution of some positive variables (happiness, optimism, and hope) to the level of psychological health in the practitioners of the nursing profession in Algeria, a total of (38) male and female nurses were employed as research sample. The researcher used a scale to measure happiness, optimism, hope, and psychological health. The results showed that the level of psychological health varies depending on the positive variables (happiness, optimism), as well as it depends on the variables of gender and professional Experience.

In this paper thermo-hydrodynamic characteristics were investigated experimentally for a new type shell-helical coiled tube heat exchanger used as a storage tank of closed loop solar water heater system. Triple concentric helical coils were made of copper tubes of (12.5mm OD and 10mm ID) with coils diameter of (207, 152.2, 97mm) for outer, middle and inner coils respectively. The experiments were carried out during a clear sky days of (March and April 2012). The parameters studied in this work are: history of average temperature of shell side of the storage tank, collector heat gain, heat rejected from coils to shell side of the storage tank, collector efficiency, thermal effectiveness of the heat exchanger (storage tank), and pressure d
... Show MoreThis research studies the influence of water source on the compressive strength of high strength concrete. Four types of water source were adopted in both mixing and curing process these are river, tap, well and drainage water (all from Iraq-Diyala governorate). Chemical analysis was carried out for all types of the used water including (pH, total dissolved solids (TDS), Turbidity, chloride, total suspended solid (TSS), and sulfates). Depending on the chemical analysis results, it was found that for all adopted sources the chemical compositions was within the ASTM C 1602/C 1602M-04 limits and can be satisfactorily used in concrete mixtures. Mixture of high strength concrete for compressive strength of (60 MPa) was designed and checked using
... Show MoreGranular carbon can be used after conventional filtration of suspended matter or, as a combination of filtration - adsorption medium. The choice of equipment depends on the severity of the organic removal problem, the availability of existing equipment, and the desired improvement of adsorption condition.
Design calculations on dechlorination by granular - carbon filters considering the effects of flow rate, pH , contact time, head loss and bed expansion in backwashing , particle size, and physical characteristics were considered assuming the absence of bacteria or any organic interface .
This study is conducted in order to, investigate the trophic state of Duhok Lake Dam located within Duhok city, Iraq. Water samples are collected seasonally from three monitored sites during 2011. The parameters used for assessing water quality and trophic status level include: water temperature, pH, EC, TDS, DO, BOD5, nutrients, Secchi disk transparency, and chlorophyll a. The results reveal that DO is above 5 mg.l-1 in all sites, BOD5 value is within permissible level for domestic uses. Water quality considered as a hard type. High sulfate concentration is recorded during the study period. Trophic state shows that water type is classified as mesotrophic during autumn season, while it is regarded as eutrophic in other seasons. TDN/TDP rati
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