Results 51 to 60 of about 4,083 (232)

Deformation and Fracture Mechanisms of Thick Hard Roofs in Upward Mining Coalfaces: A Mechanical Model and Its Validation

Applied Sciences
The safety and efficiency of underground coal mining are threatened by thick hard roofs characterized by large overhang areas, problematic spontaneous caving, and high dynamic load upon their breakage.
Wei Zhang, Linchao Cao, Dongsheng Zhang, Yang Hu, Jingyu Chang, Zhenying Zhang   +5 more
doaj   +1 more source

Applications of Advanced Presplitting Blasting Technology in the Thick and Hard Roofs of an Extra-Thick Coal Seam

Processes
Based on the engineering conditions of the 1303 working face in Zhaoxian Coal Mine, this study investigates the characteristics of mine pressure behavior and the stress-relief mechanism of advanced presplit blasting in a working face with a thick and hard roof in an extra-thick coal seam.
Shouguo Wang, Kai Zhang, Bin Qiao, Shaoze Liu, Junpeng An, Yingming Li, Shunjie Huang   +6 more
openaire   +1 more source

Re‐evaluation of a soft crested Edmontosaurin, with implications for hadrosaurid life appearance and diversity

The Anatomical Record, EarlyView.
Abstract Hadrosaurid dinosaurs are generally regarded as “crested” or “non‐crested” depending on the presence or absence of a bony cranial crest. At least one supposedly “non‐crested” hadrosaur is known to have possessed a soft tissue cranial crest (or comb), based on an exceptionally preserved “mummified” specimen. Here we redescribe this specimen and
Henry S. Sharpe, Phil R. Bell, Ian Baylatry, Robin Sissons, Corwin Sullivan   +4 more
wiley   +1 more source

The cranial, mandibular, and hyoid anatomy of softshell turtles (Trionychidae): A revised character list for phylogenetic analysis

The Anatomical Record, EarlyView.
Abstract Softshell turtles (Pan‐Trionychidae) are an early branching clade of hidden‐necked turtles (Cryptodira) with a rich fossil record extending back to the Early Cretaceous. The evolutionary history of softshell turtles is still unresolved because of their conservative morphology combined with high levels of polymorphism related to morphological ...
Léa C. Girard, Walter G. Joyce
wiley   +1 more source

Mechanism of grouped collapse of thick and hard roof for gob-side entry retaining combined backfill in fully-mechanized caving face

Meitan xuebao
A large range of caving roof of gob-side entry retaining is easy to cause impact damage of the roadside backfill body. In order to ensure the stability of gob-side entry retaining, different from the traditional large-angle inclined roof cutting method ...
Guorui FENG, Zijie MA, Wenda WU, Jianbiao BAI, Sunwen DU, Jinwen BAI, Lujin HE   +6 more
doaj   +1 more source

Redescription of the Triassic cynodont Cistecynodon parvus and reassessment of its phylogeny

The Anatomical Record, EarlyView.
Abstract Cynodontia is an important subclade of Therapsida that first occurred in the late Permian. It includes extinct subclades which are the non‐mammaliaform cynodonts and Mammaliaformes, with the latter ultimately giving rise to crown mammals. The systematics of non‐mammaliaform cynodonts has been extensively studied and is relatively well‐resolved,
Erin S. Lund, Frederik P. Wolvaardt, Roger M. H. Smith, Jaganmoy Jodder, Julien Benoit   +4 more
wiley   +1 more source

Research on the bearing characteristics of brackets in thick hard roof mining sites and the effect of blasting on roof control

Geomechanics and Geophysics for Geo-Energy and Geo-Resources
AbstractDeep mining stress increase and thick hard rock layer endowment drive rock body fissure expansion, leading to sudden fracture of the roof plate accidents. The roof slab of 11,129 working face in Zhangji Mine is a 16 m thick sandstone composite roof slab, whose compressive strength reaches 89.8 MPa.
Jiaxin Dang, Min Tu, Xiangyang Zhang, Qingwei Bu   +3 more
openaire   +2 more sources

Computed Tomography‐Based Morphometric Analysis Reveals Intercondylar Notch Stenosis and Osteophytes Are Associated With Anterior Cruciate Ligament Injury

Arthroscopy, EarlyView.
Purpose To quantitatively assess intercondylar notch morphometrics using 3‐dimensional computed tomography reconstruction, evaluate their association with anterior cruciate ligament (ACL) injury in Asian populations, and investigate the prevalence of osteophytes in patients with ACL injury.
Xiaozhong Ma, WenMing Jiang, Chao Lu, Tongyue Ji, Su Yan, Heng Zhu, Xue He, Hao Shu, Lei Wang, Luning Sun   +9 more
wiley   +1 more source

Experiment Study on the Mechanical Behavior and Acoustic Emission Response of Thick and Hard Sandstone Roof in Xinjiang Mining Area

Advances in Civil Engineering
One of the primary threats to coal mine safety production is the sudden extensive fracturing and collapse of thick and hard roof strata. A range of uniaxial compression experiments with acoustic emission (AE) monitoring was performed for studying the ...
Dongdong Qin, Zechao Chang, Ze Xia
doaj   +1 more source

Poseidon's Sanctuary at Samikon—The Discovery of an Ancient Temple Through an Integrated Geophysical and Geoarchaeological Survey Approach for Lagoonal and Swampy Environments

Archaeological Prospection, EarlyView.
ABSTRACT Below the classical fortress of Samikon at the coast of the western Peloponnese, ancient writer Strabo mentioned a sanctuary of Poseidon which served as the centre of the religious association of the Triphylian cities. In this paper, we describe the discovery and investigation of a building structure by means of geophysical and ...
Dennis Wilken, Birgitta Eder, Sarah Bäumler, Elena Appel, Peter Fischer, Tina Georg, Federica Iannone, Lena Slabon, Timo Willershäuser, Erofili‐Iris Kolia, Andreas Vött   +10 more
wiley   +1 more source