Results 121 to 130 of about 3,841 (276)

A detailed redescription of a skeletally immature ‘Redondasaurus’ suggests ontogenetic transformations in the taxon mirror phytosaurian morphological evolution

The Anatomical Record, EarlyView.
Abstract The study of morphological evolution is fundamentally tied to ontogeny, yet studies of these heterochronic processes in the fossil record are rare. Fossils belonging to an ontogenetic series are difficult to assign to an ontogenetic stage due to inconsistent proxies for skeletal ages, challenging to taxonomically assign due to morphological ...
Erika R. Goldsmith, Michelle R. Stocker
wiley   +1 more source

Study on dynamics and vibration response of shield cutterhead in composite strata based on Hertz contact

Frontiers in Mechanical Engineering
The shield cutterhead experiences eccentric loads when excavating through composite strata, leading to potential deviation of the cutterhead. This study examines the static response, modal characteristics, and vibration response of a shield cutterhead in
Huanle Xu, Huanle Xu, Junfei Fan, Junfei Fan, Zhenyu Qian, Zhenyu Qian, Changyun Yang, Xilong Zhou   +7 more
doaj   +1 more source

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

Study on the influence of TBM disc cutter on the penetration of extremely hard rock in Zijing Tunnel

Electronic Journal of Structural Engineering
The reasonable setting of TBM disc cutter penetration depth is crucial for its rock-breaking efficiency in extremely hard rock geology. In the construction section of the Dujiangyan to Mount Siguniang Zijing Tunnel project, which encountered extremely ...
Chao Gao, Yufeng Huang, Qi Geng, Xiaowu Han, Huijian Zhang, Rucheng Hu, Fei Liu   +6 more
doaj  

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

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 new type of directional drilling PDC bit used in coal mine drill

Jin'gangshi yu moliao moju gongcheng, 2016
When drilling hard formation or staggered formation,normal single layer flat base bit wears heavily.Therefore,we developed a new kind of directional drilling polycrystalline diamond composite(PDC) bit and analyzed its rock breaking mechanism and stress ...
WANG Chuanliu, JU Pei, GAO Xiaoliang
doaj  

Highly efficient hard rock-breaking tool for mining machines

IOP Conference Series: Earth and Environmental Science, 2019
BL Gerike, VI Klishin, PB Gerike
openaire   +1 more source

Born this way: Does variation in perinatal limb bone morphology predict adult locomotor repertoire in primates?

The Anatomical Record, EarlyView.
Abstract Primates show a high degree of locomotor diversity that engenders similar variance in limb bone cross‐sectional geometry and bending strength: leaping primates have stronger hindlimb bones whereas suspensory species have stronger forelimb bones.
Angela M. Mossor, Jeremy Busken, Lorna Benden, Ethan Mardovin, Andrew Bostick, Grégoire Boulinguez‐Ambroise, Timothy D. Smith, Jesse W. Young   +7 more
wiley   +1 more source

Examination of rock reinforcement and stability of the hard rock pillars due to the over-break and blast damage

, 2023
S. Spasojević, K. Skrobic
openaire   +1 more source