The performance of a batch undivided electrochemical reactor with a rotating cylinder electrode of woven-wire (60 mesh size), stainless steel 316, is examined for the removal of copper from synthetic solution of o.5 M sodium chloride containing 125 ppm at pH ≈ 3.5. The effect of total applied current, rotation speed on the figures of merit of the reactor is analyzed. For an applied current of 300 mA at 100 rpm, the copper concentration decreased from 125 to mg l-1 after 60 min of electrolysis with a specific energy consumption of 1.75 kWh kg-1 and a normalized space velocity of 1.62 h-1. The change in concentration was higher when the total applied currents were increased because of the turbulence-promoting action of the hydrogen evolution. The results suggest that the applied current must represent a compromise between the increase in space time yield or normalized space velocity and the increase in the specific energy consumption.
Portulacaria afra is a small succulent tree, previously belonging to the Portulacaceae family, but with further studies, the plant transferred to the Didieracea family. P. afra was used as an ornamental, vegetable, and ethnomedicinal plant. Uses of the plant by rural South Africans to treat chronic skin conditions and rashes, alleviate exhaustion, and aid in treating TB and diarrhea have been documented in folklore. According to pharmaceutical research, plant extracts off er a wide range of remedial outcomes, such as antidiabetic, antifungal, antibacterial, anticancer, antioxidant, and anti-infl ammatory. The study aims to determine some bioactive constituents responsible for pharmacological activities and traditional usefulness. Th
... Show MoreThe present work concerns with simulating unsteady state equilibrium model for production of methyl oleate (biodiesel) from reaction of oleic acid with methanol using sulfuric acid as a catalyst in batch reactive distillation. MESHR equations of equilibrium model were solved using MATLAB (R2010a). The validity of simulation model was tested by comparing the simulation results with a data available in literature. UNIQUAC liquid phase activity coefficient model is the most appropriate model to describe the non-ideality of OLAC-MEOH-MEOL-H2O system. The chemical reactions rates results from EQ model indicating the rates are controlled by chemical kinetics. Several variables was studied such as molar ratio of methanol to oleic acid 4:1, 6:1
... Show MoreThis work was conducted to study the extraction of pelletierine sulphate from Punica granatum L. roots by liquid membrane techniques. Pelletierine sulphate is used widely in medicine. The general behavior of extraction process indicates that pelletierine conversion increased with increasing the number of stages and the discs rotation speed but high rotation speed was not favored because of the increased risk of droplet formation during the operation. The pH of feed and acceptor solution was also important. The results exhibit that the highest pelletierine conversion was obtained when using two stages, (10 rpm) discs speed of stainless steel discs, (pH=9.5) of feed solution and (pH=2) of acceptor solution in n-decane. Assuming the existen
... Show MoreThe objective of the research is to identify the level of supervisory performance of the educational supervisor from the point of view of headmasters at secondary schools. The problem was the need to evaluate performance. A sample of (97) school headmasters was chosen to collect the needed data, they proportionated (38%) of the total community. the researcher designed a questionnaire consisted of (43) paragraphs with five areas. The results showed that there is a good level of performance among supervisors; there are no significant differences in the variable of the certificate, while there were significant differences in terms of gender for the benefit of males. The research concluded with a number of recommendations and suggestions.
... Show MoreThe mucilage from the seeds of Lallemantia royleana family Labiatae was extracted and subjected to preformulation study for evaluation of its suitability for use as suspending agent. Furosemide suspensions were prepared using (1.5% w/v) of the extracted Lallemantia royleana mucilage, (1.5% w/v) chitosan and (0.35% w/v) xanthan gum. The mucilage was white in color and the average yield of dried mucilage obtained from L.royleana nutlets was 14 % w/w of the seeds used. It is sparingly soluble in water but swells in contact with it, giving a highly viscous solution. It is slightly acidic to neutral. It was found that the extracted natural mucilage of Lallemantia royleana exhibited a higher viscosity profil
... Show MoreThis study is about awareness of teaching explanation difficulties in the Islamic university from the lecturers point of view. It discussed the difficulties and the traditional teaching methods of explanation. The study concentrated on teaching Islamic studies in general and teaching explanation in specific and set difficulties so as to be treated.
The study is of three chapters, the first contains the difficulties in several aspects like the educational goals, text contents, teaching methods and styles, students, educational techniques, educational aids and evaluation, it addition to the lecturers of Islamic university colleges in 2009-2
... Show MoreThe genus Larra Fabricius, 1793 (Hymenoptera: Crabronidae) is recorded for the first time from Vietnam. Three species and two subspecies belonging to this genus as follows: L. amplipennis (F. Smith, 1873); L. carbonaria (F. Smith, 1858); L. fenchihuensis Tsuneki, 1967; L. polita polita (F. Smith, 1858) and L. polita luzonensis Rohwer, 1919 are presented. Keys to both sexes of the three species and two subspecies reported here are provided.