Estimates of Late Albian atmospheric CO2 based on stomata of Pseudofrenelopsis from Jilin Province, Northeast China

AbstractStomata characteristics of two extinct conifer Cheirolepidiaceae species, Pseudofrenelopsis gansuensis and Pseudofrenelopsis dalatzensis were used to reconstruct the atmospheric carbon dioxide concentration levels during the late Albian of Cretaceous. A sequence of fossil samples was collected from 5 beds in the Dalazi Formation in Zhixin and Luozigou basins of Jilin Province, northeastern China. The stomatal index was used to estimate the palaeo-pCO2. The average stomatal index value of the two species was 4.1 and the atmospheric CO2 content was ∼1200 ppmv by the average of Recent standardization and Carboniferous standardization. During the short interval of 104.8±0.5 Ma to 104.0±0.4 Ma in the late Albian, the atmospheric CO2 contents present a deceasing tendency, and the highest value was ∼1300 ppmv in the Luozigou Basin. In addition, the higher atmospheric CO2 values of late Albian likely linked to a “greenhouse climate” time of Oceanic anoxic event 1c (OAE1c).

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Review for "Geochemistry and palynology of the upper Albian at the Abu Gharadig Basin, southern Tethys: Constraints on the oceanic anoxic event 1d"

10.1002/gj.3810/v2/review2 ◽

2020 ◽

Author(s):

Jean-Carlos Montero-Serrano

Keyword(s):

Oceanic Anoxic Event ◽

Anoxic Event ◽

Southern Tethys

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Communication: Photoinduced Carbon Dioxide Binding with Surface-Functionalized Silicon Quantum Dots

10.26434/chemrxiv.5944273.v1 ◽

2018 ◽

Author(s):

Oscar A. Douglas-Gallardo ◽

Cristián Gabriel Sánchez ◽

Esteban Vöhringer-Martinez

Keyword(s):

Carbon Dioxide ◽

Quantum Dots ◽

Atmospheric Carbon Dioxide ◽

Density Functional ◽

Tight Binding ◽

Carbon Dioxide Concentration ◽

Research Area ◽

Silicon Quantum Dots ◽

Dependent Model ◽

Photoinduced Charge

<div> <div> <div> <p>Nowadays, the search of efficient methods able to reduce the high atmospheric carbon dioxide concentration has turned into a very dynamic research area. Several environmental problems have been closely associated with the high atmospheric level of this greenhouse gas. Here, a novel system based on the use of surface-functionalized silicon quantum dots (sf -SiQDs) is theoretically proposed as a versatile device to bind carbon dioxide. Within this approach, carbon dioxide trapping is modulated by a photoinduced charge redistribution between the capping molecule and the silicon quantum dots (SiQDs). Chemical and electronic properties of the proposed SiQDs have been studied with Density Functional Theory (DFT) and Density Functional Tight-Binding (DFTB) approach along with a Time-Dependent model based on the DFTB (TD-DFTB) framework. To the best of our knowledge, this is the first report that proposes and explores the potential application of a versatile and friendly device based on the use of sf -SiQDs for photochemically activated carbon dioxide fixation. </p> </div> </div> </div>

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