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Tuff has been used as a natural building stone in the construction industry since the earliest times. Tuff is slight, simple to manufacture, and has good isolation qualities, which is why it is used so frequently despite its low strength characteristics and high porosity. In this study, samples of white and pink tuff from the regions of Derbent and Gümele districts of Eskisehir province were treated with a water-based (water-soluble) copolymer bath to evaluate their endurance to atmospheric conditions. Spherical samples were subjected to 30-minute slake durability index testing in a water-based copolymer bath. The index values of the initial spherical samples were contrasted with the index values from the fourth cycle of the spherical samples that had received the copolymer bath treatment. Although the index values of the original spherical samples were determined to be 92.22% and 95.32%, respectively, the index values of the spherical sample sets treated with a water-based copolymer bath were determined to be 98.29% and 98.83%, respectively. The study results indicate that spherical samples with a water-based copolymer bath treatment had a greater impact on improving the slake durability index values compared to spherical samples without treatment. [ABSTRACT FROM AUTHOR]

In solvent extraction studies, various extractants, including TOPO, Alamine 308, TBP, TOA, LIX 84I, LIX 63, and Aliquat 336, were employed for the extraction and separation of vanadium, molybdenum, and cobalt from aqueous solutions of spent petroleum catalysts. Results indicated efficient metal recovery using these extractants. Furthermore, a combination of techniques, such as roasting, chemical or bioleaching, solvent extraction (SX), and precipitation, exhibited promising results in achieving comprehensive metal extraction and separation. Important discoveries have been made in the study of recovering important metals from wasted petroleum catalysts, especially with regard to attaining high metal recovery efficiencies. It is found that the recovery efficiency for manganese is 85%, cobalt is 87%, and nickel is 93%. Furthermore, it shows that this procedure may be carried out with high efficiency, with vanadium recovery surpassing 90% and molybdenum recovery efficiency above 95%. These outcomes signify a significant advancement in the field of metal extraction and separation, aligning with the principles of Industry 5.0 while emphasizing sustainability and efficiency in the production of high-tech materials for the modern era. [ABSTRACT FROM AUTHOR]

Toxic and threatening gases are the most hazardous components of mine fires. Carbon monoxide is one of these lethal gases. It can be used to monitor the progression of fires in underground coal mines. The purpose of this study is to monitor mine fires using statistical process control. Using quality control charts, the lower and upper limits of the carbon monoxide measurement values were evaluated in the first stage. The variations in carbon monoxide readings caused by a mine fire were then analyzed using regression control charts. Positive slope changes indicated that the fire was spreading, while negative slope changes indicated that the fire had been extinguished and stable slope changes indicated that the fire was under control. By analyzing the time-dependent change of carbon monoxide in underground mines using this method, an effective methodology for controlling coal fires was established. [ABSTRACT FROM AUTHOR]

Mining has historically been known as a high-risk industry. Coal and gas outbursts are one of the most significant accidents that occur in underground coal mines. Despite many years of research, the resources and mechanisms of this phenomenon are not well understood. Thus, it is difficult to forecast and control these events. As the mining depth and density increase, initial gas pressure and gas content of coal seams continue to increase, and the risk of explosion increases. Hence, explosion-prone areas expand gradually. As a result, a dynamic phenomenon has emerged in areas where there is no danger of outbursts. The risk of outbursts becomes more and more serious in coal mines. A coal outburst risk assessment includes evaluating the risk factors to what degree are present and then determining the risk areas of the mine. In this study, the Cluster Analysis method was implemented to identify the risk level of coal seams based on the evaluation of the outburst risk factors for an underground coal mine. Coal and gas outbursts occurring in Zonguldak hard coal basin were divided into two clusters, Cluster A and Cluster B. Coal seams in Cluster A were determined riskier than Cluster B coal seams. [ABSTRACT FROM AUTHOR]

Spontaneous combustion of coal is a complex underground mining disaster, which mainly threats mine safety and efficiency. Several factors usually cause spontaneous combustion of coal, such as gas concentration, ventilation and coal properties. In this study, spontaneous combustion tendencies of coal mines were predicted considering the effective parameters for an underground coal mine in Turkey. Multinomial logistic regression, a multivariate statistical technique, was applied. Gas concentrations (CH4, CO, O2) and air velocity were defined as factors affecting spontaneous coal combustion. Fire hazard levels of the coal mines were determined as 'normal situation' and 'potential combustion'. It was observed that CH4 and CO variables and CH4 × CO interaction were effective in the formation of clusters. The results indicate that Mine I is more liable to spontaneous combustion than Mine II and Mine III. At the same time, the effects of variations in factors are examined in the study. [ABSTRACT FROM AUTHOR]

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