Gob-side entry retained with roadside filling (GER-RF) plays a key role in achieving coal mining without pillar and improving the resource recovery rate. Since there are few reports on cyclic length of GER-RF, method based stress difference is proposed to determine GER-RF. Firstly, stability analysis mechanics model immediate roof above area was established, then, relationship between distribut...

A macro-/mesoporous polymeric network with densely incorporated pillar[5]arene functionality was prepared via ionic complexation between a polymerized ionic liquid and carboxylated pillar[5]arene. It retained the solution-state host-guest property of the pillar[5]arene and was successfully applied as a selective absorbent for n-alklyene diols.

BACKGROUND Within the lateral pillar classification of the Legg-Calvé-Perthes (LCP) disease, hips seem quite variable in the pattern of fragmentation as seen in radiographs. The purpose of this study was to determine: if it is possible to reliably subdivide the lateral pillar groups into femoral head fragmentation patterns, and if such a subdivision of the lateral pillar groupings is clinically...

In underground coal mining, strata instability is one of the most catastrophic hazards, which involves sudden and violent dynamic failure pillars overlying strata. Despite decades research, contributing factors mechanisms structures are still not completely understood. Hence, it remains challenging to forecast failures quantify their likelihood occurrence. This paper deals with scope applicatio...

subject analysis of the potential of spontaneous combustion in coal layers with analytical and numerical methods has been always considered as a difficult task because of the complexity of the coal behavior and the number of factors influencing it. empirical methods, due to accounting for certain and specific factors, have not accuracy and efficiency for all positions. the rock engineering syst...

A reasonable width of the coal pillar is very important to surrounding rock control gob-side roadway. An unreasonable will make roadway be located within range strong mining influence, leading severe deformation Severe subsidence at side roof and serious are problems caused by dynamic pressure due in This paper studies instability mechanism rational under influence intense pressure. The results...

We present experimental demonstration and analysis of enhanced surface second harmonic generation (SHG) from hexagonal arrays of silicon pillars. Three sets of Si pillar samples with truncated cone-shaped pillar arrays having periods of 500, 1000, and 2000 nm, and corresponding average diameters of 200, 585 and 1550 nm, respectively, are fabricated by colloidal lithography and plasma dry etchin...

In order to recover the strip pillar coal resources, reduce amount of gangue mountain and realize remediation goaf environment in old mining area, raw filling technology was proposed. According previous practical experience, feasibility implementation coal-pressed area analyzed. Through compaction test, deformation under different loading stages obtained. Further, a reasonable prediction beyond...

The reaction of 1,4-dimethoxybenzene and paraformaldehyde using AlBr(3) yields multiple-deprotected pillar[5]arenes. A1/B2 di-deprotected pillar[5]arene can be isolated by silica gel chromatography and washing procedures. The X-ray structure and polymerization of the A1/B2 di-deprotected pillar[5]arene are reported.