Several industrial wastewater streams may contain heavy metal ions, which must be effectively removal
before the discharge or reuse of treated waters could take place. In this paper, the removal of copper( II)
by foam flotation from dilute aqueous solutions was investigated at laboratory scale. The effects of
various parameters such as pH, collector and frother concentrations, initial copper concentration, air flow
rate, hole diameter of the gas distributor, and NaCl addition were tested in a bubble column of 6 cm inside
diameter and 120 cm height. Sodium dodecylsulfate (SDS) and Hexadecyl trimethyl ammonium bromide
(HTAB) were used as anionic and cationic surfactant, respectively. Ethanol was used as frothers and the
optimal removal conditions have been established. Successful removals about (98%) and (76%) could be
achieved for copper ions with SDS and HTAB, respectively. Copper removal reached about 80% under
the optimum conditions at low pH; at high pH it became as high as 98% probably due to the contribution
from the flotation of precipitated copper. It was found that the presence of NaCl in the solution reduced
the recoveries. Adding ethanol at 1% concentration increased the removal efficiency. From the results the
rate of flotation was found to be first order.
The corrosion inhibition of aluminum alloy 5083 by an environment friendly compound called (8- Hydroxyquinoline) in
acidic and alkaline solutions of pH (2 and 12) respectively were studied using weight loss and polarization techniques.
Also to examine the main and combined effects of the inhibitor concentration, pH, and contact time using factorial
experimental design. Results show that corrosion rate decreased with increasing both inhibitor concentration and
contact time and increased with increasing pH value. The polarization curves show that 8-hydroxyquinoline is a
cathodic inhibitor
GaN thin films were deposited by thermal evaporation onto
glass substrates at substrate temperature of 403 K and a thickness of
385 nm . GaN films have amorphous structure as shown in X-ray
diffraction pattern . From absorbance data within the range ( 200-
900 ) nm direct optical energy gap was calculated . Also the others
optical parameters like transmittance T, reflectance R , refractive
index n , extinction coefficient k , real dielectric constant 1 Î , and
imaginary dielectric constant 2 Î were determined . GaN films
have good absorbance and minimum transmittance in the region of
the visible light .
Background: Pervasive Developmental Disorder (PDD) is a term refers to the overarching group of conditions to which autism spectrum disorder (ASD) belongs .
Objective: This study was designed to determine the existing behavior of children with autism in dental sitting, the behavior improvements in recall dental visits and evaluate the improvement in oral hygiene with using specific visual pedagogy chart.
Type of the study: Cross-sectional study.
Methods: Forty children of both genders, ages ranged from 4 – 6 years having primary teeth only were selected whose medical history included a diagnosis
... Show MoreOrganic Permeable Base Transistors (OPBTs) reach a very high transit frequency and large on-state currents. However, for a later commercial application of this technology, a high operational stability is essential as well. Here, the stability of OPBTs during continuous cycling and during base bias stress is discussed. It is observed that the threshold voltage of these transistors shifts toward more positive base voltages if stressed by applying a constant potential to the base electrode for prolonged times. With the help of a 2D device simulation, it is proposed that the observed instabilities are due to charges that are trapped on top of an oxide layer formed around the base electrode. These charges are thermally released after rem
... Show MoreIn this article, an attempt has been made to introduce the concept of Neutrosophic d-Filter and Neutrosophic Prime d-Filter of d-Algebra by generalizing the notion of Intuitionistic Fuzzy d-Filter of d-Algebra. Besides, we establish different properties of them. Further, we study several relations on this notion from the point of view of Neutrosophic d-Algebra.
This study focuses on the relative frequency of Streptococcus pneumoniae in children with culture-proven bacterial meningitis. The epidemiology has been investigated with clinical and laboratory findings in The Central Public Health Laboratory, Iraq from April to September, 2010. From (138) samples , (55) cases (39.85 %) were diagnosed by physician as bacterial meningitis, (23) cases (16.66 %) as viral menginitis , (18) cases (13.04 %) as different medical cases (e.g febrile convulsion , meningoencephalitis , epilepsy …etc) and (42) cases (30.43 %) as unidentified medical cases. For bacterial meningitis S.pneumoniae was isolated from (10) cases (18.18 %) only. The median age for bacterial meningitis was (130.75) month and the predomina
... Show MoreAccording to the wide appearance of Dedekind sums in different applications on different subjects, a new approach for the equivalence of the essential and sufficient condition for ( ) ( ) in and ( ) ( ) in where ( ) Σ(( ))(( )) and the equality of .two .Dedekind sums with their connections is given. The conditions for ( ) ( ) in which is equivalent to ( )– ( ) in were demonstrated with condition that of does not divide . Some applications for the important of Dedekind sums were given.
The Political loyalties of the individual considered as the most important democracies through direct psychological identification in a particular party. The political parties regarded as the important elements and the foundations of the democratic system. They have effective interaction between the voters and the government institutions. The aim of the current research is to identify the quality of Islamic, the Civilian parties, and the most preferred for students. also, the research attempt to identify the level of identification party that the university students have, and the difference of identification party according to the gender (male, female), the difference of of social class (upper, middle, poor). The sample
... Show MoreThis large book represents the research and is marked (Compilers of Hanbali jurisprudence of the Abbasid era). It includes, between its covers, a large group of scholars of the Islamic nation, with its great jurists and mujtahids, from the followers of the school of (Ahmed bin Hanbal) in the fundamentals and branches, and specific to the sciences of the Qur’an, its jurisprudence, and the narrators of the hadiths of the Noble Prophet The best of creation (Muhammad) peace and blessings be upon him, and it also includes a large number of reciters and ascetics, who are known for their abundance of authorship, especially with regard to the collection and numbers of classifications, and they are too large to be counted by number! But can we
... Show MoreA trademark is one of the most valuable elements in advertising. At the same time, it is a guarantee for both the producer and the consumer. It prevents the mixing of products with a certain mark with similar products bearing another mark; and creates confidence in the goods of the product.
With the increase in the types of goods and products and the emergence of similar goods, producers have turned to the use of the brand to identify their products and seek perfection in manufacture to maintain quality and continuous improvement which ensures good reputation and fame.
Hence, commercials for goods and services focused on the brand because they give in-depth connotations with the recipients of these ads. T
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