Results 111 to 120 of about 1,201 (198)
This study addresses hard roof coal seam conditions by optimizing key stratum blasting‐cutting parameters through theoretical analysis, numerical simulation, and field tests. It proposes calculation methods for blast hole spacing and delay timing based on stress wave theory, controlling roadway deformation within 35 mm, thereby enhancing resource ...
Qiong Liu, Duanxiang Fu, Hongbin Li
wiley +1 more source
Distribution Characteristic and Migration Mechanism of Toxic Gases in Goafs during Close-Distance Coal Seam Mining: a Case Study of Shaping Coal Mine. [PDF]
Wang D +5 more
europepmc +1 more source
As the sublevel height increases, the top‐coal recovery amount gradually increases, but both the top‐coal recovery rate and the thickened top‐coal recovery rate show a downward trend, and the decline in the top‐coal recovery rate is gradually increasing. The comparison indicates that the optimal sublevel height is 20 m.
Hongsheng Tu +4 more
wiley +1 more source
This study on close coal seams shows that multi‐seam mining increases the height of the fractured zone from approximately 26 m (single upper‐seam mining) to about 49 m. When the lower seam is mined after the extraction of the upper seam, the heights of both the caved zone and the fractured zone increase by approximately two times.
Xiaoyu Wu +4 more
wiley +1 more source
Quiet activism as feminist practice
Abstract In this article, we discuss how women combat silencing in the face of violence and increased political turmoil through quiet activism in their day‐to‐day lives. Centering lengthy conversations with Arab women across London and notes from an ongoing collaboration with a feminist activist based in the US, we examine how wearable rhetorical ...
Vicky Panossian, Catherine A. Evans
wiley +1 more source
This study reports the exceptional preservation of the Eocene freshwater bivalve Batissa sitakaraensis from Hokkaido, Japan. Multimodal analyses reveal that both the aragonitic shell mineralogy and the delicate organic periostracum retain their original structural and chemical characteristics after millions of years.
Taro Yoshimura +4 more
wiley +1 more source
ABSTRACT This study explores incidental learning among physicians navigating uncertainty during the COVID‐19 pandemic. Using a constructivist research design, we conducted a literature review of 13 empirical studies on incidental learning in complexity and analyzed critical incident interviews with 12 emergency medicine and intensive care physicians ...
Henriette Lundgren +4 more
wiley +1 more source
Foamed Concrete Sealing Materials for Coal Seam Gas Drainage Boreholes: A Review
This study investigates the sealing performance of foamed concrete in gas drainage boreholes. By comparing leakage pathways (a, c) with sealed systems (b, d), the research demonstrates how foamed concrete effectively fills mining‐induced fractures and resists deformation.
Jiaxing Zou +6 more
wiley +1 more source
The Unexpected Discovery of Paleocene? Coals in Outcrops Thought to Be Cambrian, Al Huqf, Oman
ABSTRACT Two brown organic deposits were encountered whilst investigating kaolinitic claystones thought to occur at the base of a Cambrian formation at outcrop. The age of these organic deposits is probably Paleocene from palynology. Organic petrography shows that they are subbituminous coals with some oil source potential.
Mohammed H. Al Kindi +4 more
wiley +1 more source
An integrated facies, MS and XRF‐based approach applied to the Tithonian–Berriasian Sidi Khalif Formation (central Tunisia) resolves five Tithonian and eight Berriasian third‐order sequences, showing how mixed carbonate–siliciclastic shelves record coupled eustatic, climatic and tectonic controls and providing a transferable template for similar mud ...
Hamdi Omar, Adnene Lafi, Chokri Yaich
wiley +1 more source

