This work presents a comprehensive account of how adding C3H8 impacts the possibility explosion for CH4–air mixtures. A series experiments was carried out to determine upper and lower flammability limits (UFL LFL, respectively), explosive risk value different mixtures CH4 C3H8. The critical oxygen concentration, concentrations N2 at point where LFL UFL merge, triangle were obtained nitrogen-diluted In addition, we used detailed mechanism (GRI-Mech3.0) in CHEMKIN software package acquire on...

Abstract Phase change material (PCM) is considered as one of the most effective thermal energy storage (TES) systems to balance supply and demand. A key challenge in designing efficient PCM-based TES lies enhancement heat transmission during phase transition. This study numerically examines privilege employing twisted-fin arrays inside a shell-and-tube latent unit improve solidification performance. The presence twisted fins contributes dominating role conduction by their curved shapes,...

In the present work, structure and properties of TinBn (n = 2–12) clusters were studied, microstructure a Al-Ti-B system was simulated by molecular dynamics to determine grain refinement mechanism an master alloy in Al alloy. Based on density functional theory method, structural optimization property calculations carried out. The at lowest energy levels indicated that Ti B atoms prone form TiB2 structures, structures tended be surface clusters. Ti10B10 cluster determined most stable range n...

Organic–inorganic nanocomposites comprising epoxy resins and polyhedral oligomeric silsesquioxanes (POSS) were prepared via in situ polymerization of 3,3′,5,5′-tetramethyl-4,4′-biphenyl diglycidyl 4,4′-diaminodiphenylsulfone. The thermal, fire-retardant, morphological properties the studied using thermogravimetric analysis (TGA), thermogravimetry-Fourier transform infrared (TG-FTIR) spectroscopy, microscale combustion calorimeter (MCC), limiting oxygen index (LOI), X-ray photoelectron...

In this work, we synthesized a 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) derivative flame retardant dopamine modified DOPO (DOPO-DA) for thermosetting epoxy resins (EP). The effects of different amounts retardants on the retardancy, thermal properties, and mechanical properties EP composites were studied. Compared with control EP, peak heat release rate (PHRR) EP/5 wt% DOPO-DA decreased by 26.1%. addition, EP/5wt% reached V-0 level. It can be attributed to quenching effect P...

Tunnel-boring machines (TBMs) are widely used in urban underground tunnel construction due to their fast and efficient features. However, shield-tunnel faces increasingly complex geological environments may encounter hazards such as faults, fracture zones, water surges, collapses, which can cause significant property damage casualties. Existing geophysical methods subject many limitations the environment, where detection space is extremely small, a variety of advanced unable meet required...

In order to alleviate the problem of imbalance between parking supply and demand by improving utilization rate resources, considering game relationship user benefits system in allocation, optimization objective function maximum space minimum cost reservation mode is established from two aspects which are respectively. Then, optimal allocation integer programming model (OPA) users' preferences established. An Augmented Lagrangian-Alternating Direction Method Multipliers Algorithm designed...

Parking duration analysis is an important aspect of evaluating parking demand. Identifying accurate distribution characteristics can not only enhance efficiency and facility planning, but also provide essential support for delicacy management. Previous studies have proposed various statistical distributions to depict data. However, it difficult find a certain type describe the in diverse facilities, since model uncertainty caused by stochastic behaviors environments. To address uncertainty,...

In order to achieve better economic benefit and social impression, tobacco enterprise must establish effective operable performance appraisal system. It is very important select indexes their weight for appraisal. the paper, AHP-based (analytic hierarchy process) studied by case. The result indicates that sales volume, inventory purchasing plan are indexes.

There is a small amount of other flammable gases than the major constituent methane in mine gas. The have critical effects on gas explosion. Appropriate understandings chemical kinetic characteristics CH4-air explosion are essential to prevent and control mine. Therefore, numerical simulations conducted through software CHEMKIN investigate effects. present study mainly analyse variation pressure, temperature, products, free radicals sensitivity CH4 process after addition C2H4. results...

Various solutions, such as parking reservation systems, have been proposed to alleviate the difficulty in finding slots. In requests are submitted advance by drivers, and systems will reserve appropriate spots for drivers if their accepted. However, slots may be allocated unreasonably, which lead a waste of space time resources. addition, there is game relationship between operator’s profit (OP) users’ benefits (UB), affect sustainable development system, balanced improperly. Given drivers’...

Biochar can facilitate the bioreduction of Cr(VI), an essential heavy metal pollutant in environment. Cr(VI) consists both fast and slow processes terms kinetics efficiency, but roles biochar these two remain unclear. In this study, we employed a “dual-process model” to explore mechanism enhanced by biochar. The was mainly dominated cell-biochar complexes formation. fast-bioreduction rates (rf0) were almost 2-15 times higher than slow-bioreduction (rs0). Both conductivity smaller particle...