CO in coal mine underground spaces can easily cause casualties among miners. The humidity mines is relatively high, and traditional Cu-Mn catalysts are prone to deactivation. Compared catalysts, doping with Sn enhances the activity water resistance of catalysts. Cu-Mn-Sn catalyst was tested using XPS, FTIR, a self-made Activity Test Experimental System, partial data processed Avantage software. results show that increases number active sites (Cu+) on proportion surface adsorbed oxygen (Oads)...

Abstract To ensure the safe construction of prefabricated buildings and improve efficiency evacuation personnel after a fire caused by improper operation during construction, this study used PyroSim software to numerically simulate situation based on size volume building site. The variation rules smoke visibility, CO concentration, ambient temperature in site were analyzed available time was determined. Moreover, Pathfinder for simulation combination with physical attributes personnel,...

The adsorption capacity of coal with respect to carbon dioxide (CO2) is greater than that methane (CH4). Studying the CO2 replacement CH4 in essential understanding mechanism behind CO2-enhanced coalbed methane. In this paper, scanning electron microscopy was used qualitatively study influence injection pressure on fracture characteristics coal. time effect CH4/CO2 and were quantitatively studied using low-field nuclear magnetic resonance. results suggest three different states samples:...

Abstract The increasing depth of mine excavation presents greater challenges in ventilation and managing cooling energy consumption. Therefore, there is an urgent need for comprehensive research on jet influenced by low-speed crossflows. This study investigated the impact flow velocity ratios ( R ) exit diameters d flow-field distribution characteristics through measurements smoke visualization experiments. results revealed two distinct types air lakes formed crossflow (JVIC), with one being...

To ensure the safety and emergency evacuation of university library buildings improve efficiency safe personnel after an emergency, this study considered actual size volume libraries. The project main campus Liaoning Technical University was modeled using Pathfinder software. By considering site load, attributes, speed, ratio, a simulation conducted to analyze effect stacked items’ quantity location number items, such as tables, chairs, bookshelves, other factors on time required for through...

The injection of CO2 into a coal seam can effectively improve the recovery efficiency coalbed methane. Existing CO2-enhanced methane(ECBM) is mainly focused on improving physical free CH4. In macro experiments, it difficult to simultaneously separate adsorbed CH4 and CH4; therefore, there are few studies using seams. this study, LF-NMR method was used evaluate transformation law during process, enhancement quantified. results showed that formed T2 peaks, allowing them be distinguished....

To determine the characteristics of air leakage concerning a "Y" type ventilation in gob-side entry retaining with roof cutting, pressure relief, and law resulted gas accumulation (GA), research is conducted by employing CFD simulation incorporated gauged parameters working face (WF) mining to analyze ventilation. For this purpose, 1201 fully mechanized coal south Wu location Daxing mine taken as an illustrative example study So, concentration (GC) issue surpassing limit upper corner goaf...

In order to address the issue of safe and efficient extraction coalbed methane in H2S-containing coal mines, this study explored impact H2S on CH4 diffusion displacement within coal. The molecular structure model Guizhou Linhua (LH) was obtained based structural physical characterization experiment such as 13C NMR, FTIR, XPS, we investigated coefficient under different fixed adsorption amounts examined corresponding curves mixed gas (H2S, CH4, CO2) varying component proportions using...

The permeability enhancement is the key to increase efficiency of gas drainage from low-permeability coal seam. In this paper, acid fracturing technology proposed solve problem low seam with high mineral content. self-developed coal-rock experimental system used study whole process under different stress conditions and specimens varying enhancing methods. surface characteristics content before after were tested by SEM XRF technologies. test results show that effect acidizing mainly dominated...

To study the influence of different volatile contents on explosion characteristics coal dust, content in dust was controlled under final temperatures pyrolysis. The maximum pressure, pressure rising rate, and index were used to characterize behavior, ratio explosibility, minimum ignition temperature cloud sensitive characteristics. A 20 L nearly spherical parameter measuring device a with prepared pyrolysis conditions. results showed that matter lignite has little effect an average change...

To improve the thermal health state of workers in mines facing heat hazards and enhance cooling capacity utilization efficiency mine ventilation, this study proposes a suitable air distribution for workers' local cooling, taking into account characteristics long-narrow underground space workers. The suggested involves harnessing cold jets along with mine's crossflow (mainstream ventilation) to create localized safeguard airflow around worker's head-neck, known as jet ventilation (JVIC). flow...

Coal spontaneous combustion (CSC), when not properly controlled during the process of closure, is extremely prone to secondary disasters-gas explosion. Thus, prevent gas explosion accidents, it important understand characteristics coal generation law under different air volumes. This study utilized a tube furnace temperature-programmed experimental system investigate in few samples. The results demonstrated that oxygen concentration inversely related CO and C2H4 can be divided into four...

Abstract It is necessary to change the air supply rate of working face during withdrawal fully mechanized mining, making it important study oxidation characteristics coal samples under different rates. Through a self-made temperature-programmed experimental device, our focus was on studying laws indicator gases released low-temperature (303.15–473.15 K) stage when rates were 0.67, 1.33, 2, 2.67, and 3.33 mL/s. The results showed that increased, concentrations CO, C 2 H 6 , 3 8 4 generated by...

Camellia oleifera is one of the four woody oil plants in world, which widely cultivated South China. To examine genetic diversity C. China, and relationships among within major populations 109 varieties were analyzed using ISSR markers. Twenty-three primers out 49 yielded approximately 487 legible bands. A total 335 these bands polymorphic markers, ratio polymorphism was 68.86%. From results, Zhejiang province showed highest (H value 0.18), while Guangxi population lowest 0.0851). Base on...

This paper investigated the effectiveness of a vent burst door in isolating shock waves gas explosions coal mines and to reveal mechanisms explosion overpressure. A 17.5 m × φ 0.63 columnar test duct with similar shape roadways was designed. Explosion overpressure propagation characteristics effects methane concentration at different locations along without were experimentally investigated. The results demonstrate that plays significant role sealing area propagation. properly designed is...

To study the law of influence an explosion venting door on gas characteristics and verify its effect fast sealing performance, a large-sized pipeline experimental system was used. The tests were carried out under conditions 5.5, 7.5, 9.5, 11.5% concentration. characteristic parameters measured by data acquisition system. laws change in flame-proof analyzed. results showed that pressure peak attenuated 42.25, 50.54, 53.27, 52.88% aforementioned four working conditions. As volume fraction...