Results 71 to 80 of about 75,496 (347)
Life in Pre-Cambrian and early Cambrian times [PDF]
Geological Society, London, Special Publications, 1967 Summary Physical and chemical conditions which could have favoured the origin of life on Earth are briefly discussed, together with the evidence of the geological record. Free oxygen may be of critical importance as a factor in the early evolution of life.
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Causes of the Cambrian Explosion [PDF]
Science, 2013 The rapid diversification of animal species in the early Cambrian was the result of a range of interacting biotic and abiotic processes.
Smith, M.P., Harper, D.A.T.
openaire +4 more sources
Supervariate Gel Transforms into Various Biominerals in Salt Solutions
Advanced Functional Materials, EarlyView.It is revealed that common calcium‐based biominerals can form from a stable, non‐toxic ‘supervariate’ gel. This tunable gel selectively yields calcite or hydroxyapatite in carbonate/phosphate solutions, while CaCl₂ facilitates the formation of dihydrate calcium pyrophosphate, which converts to hydroxyapatite upon drying. These findings provide insights
Xinxue Tang +12 more
wiley +1 more source
Stratigraphy of the Khuvsgul Group, Mongolia
Mongolian Geoscientist, 2021 The Khuvsgul Group (Khuvsgul Province, Mongolia) is a Late Neoproterozoic to Cambrian carbonate-dominated succession that includes minor glacial diamictite and one of the largest known ore-grade phosphate deposits in the world.
Eliel Anttila +2 more
doaj +1 more source
Biomineralization of the Cambrian chancelloriids
Geology, 2021 Abstract As extinct animals that flourished during the Cambrian explosion, chancelloriids have a unique body plan lacking guts but with a flexible integument and a suite of star-shaped, hollow sclerites. Due to this body plan, along with the paucity of knowledge on sclerite biomineralization, the phylogenetic position of chancelloriids ...
Guoxiang Li +7 more
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Advanced Materials Technologies, EarlyView.In situ, nanoparticle doping enhances the piezoelectric coefficient (**d₃₃**) of PVDF to ≈12 pC/N, while in situ growth of AgF and Ag₂O dopants increases β‐phase concentration. The nanogenerator achieves a 35 V open‐circuit voltage and 1.6 µA short‐circuit current, powering 10 blue LEDs and charging a 50 nF capacitor within 10 s.
Renjun Liu +15 more
wiley +1 more source
Developing Ecospheres on Transiently Habitable Planets: The Genesis Project [PDF]
Astrophysics and Space Science, Vol 361, 324 (2016), 2016 It is often presumed, that life evolves relatively fast on planets with clement conditions, at least in its basic forms, and that extended periods of habitability are subsequently needed for the evolution of higher life forms. Many planets are however expected to be only transiently habitable.
arxiv +1 more source
Trimness of Closed Intervals in Cambrian Semilattices [PDF]
, 2015 In this article, we give a short algebraic proof that all closed intervals in a $\gamma$-Cambrian semilattice $\mathcal{C}_{\gamma}$ are trim for any Coxeter group $W$ and any Coxeter element $\gamma\in W$. This means that if such an interval has length $
Mühle, Henri
core +3 more sources
Himalayan Cambrian brachiopods
Papers in Palaeontology, 2015 AbstractA synoptic analysis of previously published material and new finds reveals that Himalayan Cambrian brachiopods can be referred to 18 genera, of which 17 are considered herein. These contain 20 taxa assigned to species, of which five are new: Eohadrotreta haydeni, Aphelotreta khemangarensis, Hadrotreta timchristiorum, Prototreta?
Nigel C. Hughes +5 more
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Advanced Energy Materials, EarlyView.Layer‐by‐layer processed pseudo‐bilayer heterojunctions offer flexible processing strategies, optimized morphology, enhanced efficiency and stability, and scaling potential for organic solar cells. Abstract Recent progress in organic (semiconductor) solar cells (OSCs) has led to power conversion efficiencies (PCEs) reaching 20%, with predictions that ...
Donghui Li +5 more
wiley +1 more source