This study has been performed to study the inhibitory effects of crude plant extracts of Bay (laurus nobilis) leaves against some bacterial isolates represented by Staphylococcus aureus, Staphylococcus epidermids, Proteus vulgaris, Bacillus subtilis, Escherichia coli, and Pseudomonas aeroginosa in vitro. The results showed that percentages of essential chemical of laurus nobilis leaves which represented by moisture, total oil, total ash, crude protein, crude fibers, carbohydrites and caloric values in dry weight are 5.96, 4.28, 14.2, 8.75, 24.8, 76.99%, and 284.92 kcal/100g respectively, the percentages of some major and minor mineral elements of laurus nobilis leaves powder which represented by Mg, Fe, Cu, Pb, Cd and As, are: 0.211, 0.165, 0.023, 0.011, 0.00, 0.0004 mg/g and 3.140 ppm, respectively, while Co did not appear in the laurus nobilis leaves. The aqueous extract of the plant was acidic its pH 5.79. The results of initial detection (precipitation) showed that ethyl acetate and aqueous extracts of laurus nobilis leaves contain all active compounds represented by tannins, saponins, flavonoides, glycosides, phenols, terpenoids, sterols and cumarin, while alcoholic and hexan extracts contain also the some compounds except saponins, hexane extracts no phenols. Through the study of the effect of laurus nobilis leaves extracts against growth of bacteria in vitro a significant differences at (p<0.05) was observed, It was found that the ethyl acetate and alcoholic extracts more were effective on the bacterial species than the other remaining extracts against the growth of bacteria, inhibitory activity was of all bacterial species at concentration of 3.125mg/ml and it was more effective on Staphyloccocus epidermids for ethyl acetate extract giving inhibitory zone estimated 15.5mm, while alchoholic extract was activity against bacteria E. coli at inhibition zone estimated 15mm, while hexan extracts has been showed inhibition activity of same concentration only on bacteria Staphyloccocus aureus with zone 10.5mm, as for it has been showed inhibitory activity of bacteria Proteus vulgaris at concentration 12.5mg/ml with zone 13mm, as for Staphyloccocus epidermids, Bacillus subtilis, E. coli and Pseudomonas aeroginosa were their inhibition activity at concentration 25mg/ml while Staphyloccocus aureus was highest inhibition at zone 16.5mm and 14mm of same concentration as for the hexan and aqueous extracts respectively, while the inhibition of bacteria Proteus vulgaris was zone 10mm of aqueous extract, inhibitory activity of bacteria Pseudomonas aeroginosa has been showed at concentration 50mg/ml of zone 16mm, as for the bacteria Staphyloccocus epidermids, Bacillus subtilis were the inhibitory zone at 12mm and E. coli at zone 18mm of concentration 100mg/ml. When measuring the minimum inhibitory concentration (MIC) for each bacterial species at a concentrations 6.25- 12.5mg/ml for ethyl acetate and alcoholic extracts have high inhibitory activity compared with the other concentrations, but the hexane and aqueous extracts have affected bacterial species at 12.5- 100 mg/ml, except for Staphyloccocus aureus and Bacillus subtilis, which was not affected by any of the concentrations of extracts.
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Polypyrrole/silver (PPy/Ag) nanocomposites was synthesized via a chemical oxidative method. The AFM analysis is performed to study the surface roughness, morphology and size distribution of the PPy particles and PPy-ag nanocomposites. The results indicated that as the concentration of Ag in the nanocomposite increases, the roughness also increases. The size of nanoparticles was also evaluated and found in the range of 15 nm to 125 nm. The PPy/Ag nanocomposites exhibited an effectiveness against Gram-negative Escherichia coli showing an inhibition zone of 4mm and displayed poor efficacy against Gram-positive Staphylococcus aureus. Based on given adequate antibacterial characteristics of PPy/Ag nanocomposites, it can be identified as a pro
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Polypyrrole/silver (PPy/Ag) nanocomposites was synthesized via a chemical oxidative method. The AFM analysis is performed to study the surface roughness, morphology and size distribution of the PPy particles and PPy-ag nanocomposites. The results indicated that as the concentration of Ag in the nanocomposite increases, the roughness also increases. The size of nanoparticles was also evaluated and found in the range of 15 nm to 125 nm. The PPy/Ag nanocomposites exhibited an effectiveness against Gram-negative Escherichia coli showing an inhibition zone of 4mm and displayed poor efficacy against Gram-positive Staphylococcus aureus. Based on given adequate antibacterial characteristics of PPy/Ag nanocomposites, it can be identified as
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In this research is to study the influence of the aging heat treatment on the pitting corrosion resistance of martensitic stainless steel (MSS), where a number of specimens from martensitic stainless steel were subjected to solution treatment at 1100 oC for one hour followed by water quenching then aging in the temperatures range (500-750) oC for different holding times (1,5,10,15&20) hr. Accelerated chemical corrosion test and immersion chemical corrosion test were performed on samples after heat treatment. The results of the research showed that the pitting corrosion resistance is significantly affected by the aging temperature. Where found that the aging samples at a temperature of 500 °C have the highest ra
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The study of surface hardness, wear resistance, adhesion strength, electrochemical corrosion resistance and thermal conductivity of coatings composed from sodium silicate was prepared using graphite micro-size particles and carbon nano particles as fillers respectively of concentration of (1-5%), for the purpose of covering and protecting the oil distillation towers. The results showed that the sodium silicate coating reinforced with carbon nano-powder has higher resistance to stitches, mechanical wear, adhesive and thermal conductivity than graphite/sodium silicate composite especially when the ratio 5% and 1%, the electrochemical corrosion test confirmed that the coating process of stainless steel 304 lead to increasin
... Show MoreDans le roman moderne, le type du héros est depuis longtemps devenu suspect. Il risque même de disparaitre dans ce qu´on désigne le Nouveau Roman qui, se concentrant plutôt sur les objets, décrits minutieusement, refuse la fonction épistémologique traditionnelle de la littérature. Cette conception se manifeste, sur le plan formel, par certains traits typiques, comme la relativisation des points de vue, la décomposition de l´action, la destruction du temps, la décomposition de l´espace et la désintégration du personnage romanesque dont les liens avec la société sont coupés.
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 do
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The problem of slow learning in primary schools’ pupils is not a local or private one. It is also not related to a certain society other than others or has any relation to a particular culture, it is rather an international problem of global nature. It is one of the well-recognized issues in education field. Additionally, it is regarded as one of the old difficulties to which ancient people gave attention. It is discovered through the process of observing human behaviour and attempting to explain and predict it.
Through the work of the two researchers via frequent visits to primary schools that include special classes for slow learning pupils, in addition to the fact that one of the researcher has a child with slow learning issue, t
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Forty one isolates of genus Proteus were collected from 140 clinical specimens such as urine, stool, wound, burn, and ear swabs from patients of both sex. These isolates were identified to three Proteus spp. P. mirabilis, P. vulgaris and P. penneri .The ability of these bacteria to produce L-asparaginase II by using semi quantitative and quantitative methods was determined. P. vulgaris Pv.U.92 was distinguished for high level of L-asparaginase II production with specific activity 1.97 U/mg. Optimum conditions for enzyme production were determined; D medium with 0.3% of L-asparagine at pH 7.5 with temperature degree 35°C for incubation. Ultrasonication was used to destroy the P. vulgaris Pv.U.92 cells then ASNase II was extracted and pu
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