Analysis and Control of mortar Quality with ultrasonic wave attenuation

Wave propagation and attenuation on mortar material are discussed in this paper with a Non Destructive Testing (NDT) which can be used to characterize samples of mortars and effect of microstructure of sand in their hardening. Samples were manufactured using same water/cement ration (w/c) 0.65, and cement/sand ration (c/s) 0.5 in order to simulate the attenuation. The characterization of attenuation in mortar material has been performed by ultrasonic reflection technique using a transducer with central frequency 0.5MHz. It is shown that sand particle size exercises significant influence on the evolution of attenuation, the attenuation parameters give information about average state of the hardening of the mortar itself

Evaluación de la eficacia de aceites de fritura con técnicas ultrasónicas

The performance of unhydrogenated soybean oil (USBO) and partially hydrogenated soybean oil (PHSBO) was evaluated by comparing their frying stability. Ultrasonic velocity was used to evaluate the oils. Measurements of free fatty acids (FFA) and total polar compounds (TPC) are typical indexes of oil degradation. Oils were heated at 180 °C for periods of 8 h per day for 4 consecutive days. The results from the ultrasonic analyses show different influences of thermo-oxidation on USBO and PHSBO. The ultrasonic measurements had strong correlations with chemical changes. Consequently, the ultrasonic method is useful to obtain information on the quality of the used frying oils.La eficacia de aceites de soja sin hidrogenar (USBO) y aceites de soja parcialmente hidrogenado (PHSBO) fue evaluada por comparación de sus estabilidades de fritura. La velocidad ultrasónica fue usada para evaluar los aceites. La medida de ácidos grasos libres (FFA) y compuestos polares (TPC) son típicos índices de degradación de aceites. Los aceites fueron calentados a 180 °C en periodos de 8 h por día durante 4 días consecutivos. Los resultados del análisis ultrasónico muestran diferentes influencias de termooxidación en USBO y PHSBO. Las medidas ultrasónicas tuvieron una fuerte correlación con cambios químicos. Consecuentemente, el método ultrasónico es útil para obtener información en la calidad de aceites de fritura usados

Performance of different silicon PV technologies installed in Laâyoune –Morocco

The results presented in this paper concerned a comparative and performance analysis of three PV technologies Monocrystalline (2kWp), Polycrystalline (1.82kWp) and Amorphous (1.55kWp). These technologies are linked together and formed a grid connected station of total capacity 5.365kWp that is located on the roof of the High School of Technology-Laâyoune-Morocco. The analyses of this installation was made by determining the performance, productivity, performance ratios and yields of three PV technologies for one year, from March 2018 to February 2019. Parameters like annual specific yield, annual capacity and performance ratio were evaluated and found to be 1876.37kWh/kWp/year, 21.42%, and 81.83%, for Polycrystalline, 1405.51kWh/kWp/year, 16.12% and 57.92% for Monocrystalline and 1865.81kWh/kWp/year, 21.31% and 80.03% for Amorphou

Ultrasonic Characterization and Hardening of Mortar Using the Reflection Technique

International audienc

Characterization Of Mortars With Ultrasonic Transducer

International audienceThe durability of mortar structures is affected by chemical and mechanical factors, such as abrasion, temperature variation..., the Degradation of mortar structures located under flowing water in their structure or high humidity atmospheres. In this study we presented a method for ultrasonic non-destructive characterization in mortar to follow the evolution of the signals back scattered by mortar structures for different size of sand, Samples were manufactured using same water/cement ration (w/c) 0.65, and cement/sand ration (c/s) 0.5. The processing of the ultrasound wave has been chosen to follow the hardening of mortar and to understand the mechanisms driving to the degradation of mortar in relation with microstructure