Studies of the Influence of Temperature on the Photocatalytic Activity of Tungsten Oxide

The results of photocatalytic activity of tungsten oxide in visible light are analyzed. It was shown that tungsten oxide has photocatalytic activity under the action of visible light in the photodegradation of the dye methylene blue. It was determined that the concentration of 15 mg/L provides the highest rate of photodecomposition of methylene blue. The optimum temperature for the process was determined. The process of methylene blue decomposition is most effective at 25 °С.

Impact of Heat on the Different Stages of the Production of Local Beer “Tchoukoutou” Made from Sorghum

Tchoukoutou is a local alcoholic drink made from sorghum. The optimization and good quality of this drink depend on certain factors such as temperature that were the subject of our work. To carry out this study, we have set ourselves the general objective of structuring the production of Tchoukoutou. Specifically, the study aims to systematize the cooking of the wort, to verify the properties of the beer through tests and to produce a quality drink. An investigation was made on the influence of temperature on sorghum germination and wort cooking. The study of the effect of temperature on the germination of sorghum was carried out. It concerned four different temperature levels which are: 23 ° C, 26 ° C, 30 ° C and 35 ° C. A study of the influence of temperature on brewing was done with different varieties of sorghum and also at different temperature ranges: 78 ° C, 83 ° C, 89 ° C, and 92 ° C. The results showed that the ideal germination temperature is 30 ° C and for brewing it is 78 ° C. The soaking time during germination, for a good germination rate, is between 16h and 26h. In conclusion, the temperature factor is a parameter that should not be overlooked when making Tchoukoutou. Our study thus made will serve as a basis for subsequent studies in the same direction to achieve a standardized industrial production of Tchoukoutou.

Review of studies on plugging compositions creation with controlled rheological properties and the ability to restore fluidity for completion, workover and abandonment of oil and gas wells

The main purpose of cementing oil and gas wells is zonal isolation of the formations exposed by the wellbore. During the entire life of the well, there should be no uncontrolled hydraulic communication between the developed formations and the surface, regardless of the composition and type of fluid (water, oil or gas). During the operation of the well, in addition to constant static ones, the casing and cement stone also experience various dynamic loads. The article presents an up-to-date review of experimental studies on the modification of grouting compositions and cement composites capable of autonomous selfhealing due to the introduction of various additives and nanomaterials. Such modification technologies significantly increase the tightness and resistance of cement to the effects of dynamic loads, the integrity of the cement stone. As a replacement for traditional cement materials, the authors propose the creation of grouting compositions with controlled physical and mechanical properties and the possibility of their re-liquefaction under the influence of temperature on the basis of bitumen or bitumen composites. Keywords: well plugging and abandoning; self-healing materials; autonomous self-healing; casing durability; impermeability of the cement stone; self-healing cement; bitumen and bitumen composites.