Delamination in a chimney, modelling and analysis

Abstract Non-destructive testing plays an important role in areas where security requirements are important, such as nuclear, automotive, aviation, rail and particularly in civil engineering structures. The used techniques are various: ultrasound, X-ray, infrared and the choice of a particular method depends on the structure geometry, the material nature and the required accuracy. In this range of methods, thermal non-destructive control based on infrared thermography has the advantage to be well suited to auscultation of large structures without any contact with them and the results can be exploited immediately without any prior treatment. In this work, we present the results of simulations on non-destructive thermal characterization of a wall chimney having internal defects in form of cracks. In this application, the model is based on the finite element method. The influence of the size, position and nature of defects in the wall chimney are studied

Oleuropein and Antibacterial Activities of Olea europaea L. Leaf Extract

In this study, we reported the determination of phenolic compounds in olive leaves by reversed phase HPLC/DAD and the evaluation of their in vitro activity against several microorganisms. These organisms might however, be causal agents of human intestinal and respiratory tract infections. Extract of the leaves of two varieties of Olea europaea L. (Chemlel and Dathier) was investigated for antibacterial activity against four pathogenic bacteria. Leaves extract was prepared using water and methanol (20/80) in a cold extraction process. The tested bacteria were Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus .The extracts were found to be effective against all isolates tests. Ethanolic extract at a concentration of 100 % presented the highest potential of inhibiting variety of Dathier against S.aureus .This is with an inhibition zone of 17.49 mm and 15.66 mm for the variety Chemlel against S.aureus. The high Oleuropein content and the important antibacterial activities of olive leaves extract could be useful sources for industrial extraction and pharmacological application

Fe(III)-Citrate-Complex-Induced Photooxidation of 3-Methylphenol in Aqueous Solution

The photodegradation process of m-cresol (3-methylphenol), induced by Fe(III)-Cit complex, was investigated upon irradiation at 365 nm in natural water. The composition and photochemical properties of Fe(III)-Cit complex were studied by UV-Visible absorption spectrophotometer for optimizing the stoichiometry of the complex and photolysis under irradiation at 365 nm, respectively. A dark investigation of the system was performed before studying the photochemical behavior. The photooxidation efficiencies of m-cresol were dependent on the pH value, optimized at pH 2.86, oxygen, initial concentrations of Fe(III)-Cit complex, and m-cresol. Additionally, to look into the mechanism of m-cresol degradation using Fe(III)-Cit, tertiobutanol alcohol was used as scavenger for hydroxyl radicals and the result suggested that hydroxyl radical attack was the main pathway of m-cresol degradation. Besides, oxygen can enhance the photolysis of Fe(III)-Citrate complex by trapping the electron on the carbon centered radical formed after the photoredox process. Then O •− 2 formed reacts rapidly leading finally to formation of • OH radical. In absence of oxygen, less reactive species are formed; consequently the disappearance of m-cresol was strongly inhibited. Our work shows that the presence of Fe(III)-Citrate complex could have a considerable impact on the fate of organic pollutant in aquatic environment

Microwave sensor for liquid mixture identification based on composite right left hand-zero-order resonator for sensitivity improvement

YesThis work aims to present an improved version of the liquid mixture identification sensor, the proposed sensor is tested experimentaly on mixture of water ethanol, the identification of liquid is based on the measurement of frequency displacement, and comparison with reference values of water ethanol. This device is based on metamaterial structure which is a CRLH (composite right left hand) resonator with ZOR (Zero Order Resonator). The CRLH in addition to its property of miniaturization effect, when combined with ZOR, the resonant frequency of various volume fraction are extended, which make the sensitivity higher. The high sensitivity of the sensor is obtained by an optimum choice of the CRLH components. The geometrical size of the sensor is 20 mm by 11 mm. It was printed on a RT/Duroid 5880 substrate with a very short testing surface area of 4 mm by 8 mm, the liquid is placed on the top side of the sensor, exactly on the CRLH structure. Three prototypes of sensors operating from 1 GHz to 3 GHz are proposed, designed and simulated using the commercial software HFSS (high-frequency structural simulator). The main advantages of this work is first miaturization effect, second high sensitivity and finaly a wide range of liquid can be tested with this sensor. To prove the working principle, ethanol with different volume fractions was adopted as a liquid under test, the obtained results present very good agreement with the literature and suggested that it is a miniaturised and high sensitive candidate (better than 1.38%) for liquid mixture identification

Anticoagulant Activity of Some Ficus carica Varieties Extracts Grown in Algeria

The hemostatic system is a complex balanced system that triggers clot formation to prevent blood loss after trauma. To block abnormal bleeding and maintain intravascular blood in a liquid state, in this study we investigated the possible anticoagulant effect of leaves and fruits extracts from some fig varieties grown in Algeria by determining the quick time (QT). The blood samples of the healthy individuals were used. For in vitro coagulation assays, the clotting times obtained in the presence of polyphenols in different extracts of F.carica samples indicate that they exert a high anticoagulant activity on the exogenous pathway of coagulation. Moreover, the polyphenolic extract of ‘Roudane’ variety presented a substantial increase in coagulation. Based on these preliminary results, it can be suggested that the fig polyphenolic extracts (FPE) of this varieties have anticoagulant activity that could be useful in preventing blood clots

Experimental and numerical non-destructive study of defect in concrete

This paper verifies the reliability of the numerical methods in reflecting the experimentation in the field of non-destructive testing by infrared thermography. A non-reinforced concrete slab (1 m × 1 m × 0.25 m) containing four defects was used, two of which had the void type and two had honeycombs type. The defects were situated from 5 cm and 10 cm of the surface. The response of the slab to thermal excitation was investigated by determining the variation of temperature at the top surface of defects and at the slab surface by simulation and experimentation. A good correlation was noted between the numerical results and the experimentation for the three studied durations of thermal excitation (30 min, 60 min and 90 min)