Results 51 to 60 of about 15,213 (255)

The coelurosaur theropods of the Romualdo formation, early Cretaceous (Aptian) of Brazil: Santanaraptor placidus meets Mirischia asymmetrica

The Anatomical Record, EarlyView.
Abstract The upper carbonate concretion levels of the Romualdo Formation (Aptian, Brazil) have yielded several theropod dinosaur remains, including spinosaurids and the coelurosaurs Santanaraptor placidus and Mirischia asymmetrica, the phylogenetic affinities of which are controversial.
Rafael Delcourt, Orlando Nelson Grillo, Christophe Hendrickx, Maximilian Kellermann, Max Cardoso Langer   +4 more
wiley   +1 more source

Structural quantification of multi-thick hard roof and strong ground pressure control in large mining height stope: a case study

Geomechanics and Geophysics for Geo-Energy and Geo-Resources
The mining of deep large-height longwall faces leads to frequent occurrences of strong ground pressure, at the same time, there are multi-thick hard rock strata in the roof of the longwall face, therefore, it is important to master the fracture ...
Yangbo Lu, Shaohong Yan, Kunyou Zhou, Chenxi Zhang, Yi Zhou   +4 more
doaj   +1 more source

An ontological morphological phylogenetic framework for living and extinct ray‐finned fishes (Actinopterygii)

The Anatomical Record, EarlyView.
Abstract The ray‐finned fishes include one out of every two species of living vertebrates on Earth and have an abundant fossil record stretching 380 million years into the past. The division of systematic knowledge of ray‐finned fishes between paleontologists working on extinct animals and neontologists studying extant species has obscured the ...
Jack Stack
wiley   +1 more source

Optimization simulation of fracturing parameters under different soft/hard coal + surrounding rocks in Yuwu Mine

Meikuang Anquan
In order to improve the effectiveness of hydraulic fracturing, a numerical simulation software for hydraulic fracturing was used to address the issues of large differences in strength and poor compatibility between hydraulic fracturing parameters and ...
Shaowei HAO, Jingshuo ZHANG, Ruijie CHEN, Yafei JING   +3 more
doaj   +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

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

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

Cranial anatomy of a Late Cretaceous aspidorhynchid fish (Neopterygii: Aspidorhynchiformes) from Alberta, Canada

The Anatomical Record, EarlyView.
Abstract Belonostomus longirostrisis was named for an isolated jaw fragment from freshwater Upper Cretaceous (Campanian) sediments of the Dinosaur Park Formation of Alberta, Canada. Following the description of the Albertan species, numerous isolated cranial and postcranial elements have been collected from the Dinosaur Park Formation and assigned to B.
Mondo Miyazato, Luke E. Nelson, Joshua A. Doyon, Donald B. Brinkman, Alison M. Murray   +4 more
wiley   +1 more source

Evolution of roof treatment processes from blasting to hydraulic fracturing to prevent rockburst in thick-hard roof coal mines in Xinjiang, China

Frontiers in Earth Science
Rockburst prevention poses a major challenge in coal mining, with thick and hard roof strata being the primary cause of rockbursts. To analyze the feasibility and effectiveness of using hydraulic fracturing as an alternative to blasting methods for ...
Kunlun Liu, Taotao Du, Taotao Du, Yuhai Wu, Hongping Li, Xu Yang, Jiang Liu, Hongbao Liang, Jianqi Wang   +8 more
doaj   +1 more source

Research of cumulative energy blasting technology with deep and shallow hole combined in hard roof

矿业科学学报, 2020
To solve the problems of low crack rate and large overhanging roof after directional presplitting cumulative blasting technology is implemented under the condition of hard roof, through theoretical analysis, numerical simulation and field monitoring, the
Li Minzu, Ma Zimin, Xue Dingliang, Yuan Yunhai   +3 more
doaj   +1 more source