scholarly journals First spectroscopic identification of pyrocarbonate for high CO2 flux membranes containing highly interconnected three dimensional ionic channels

2013 ◽  
Vol 15 (31) ◽  
pp. 13147 ◽  
Author(s):  
Lingling Zhang ◽  
Xinyu Huang ◽  
Changyong Qin ◽  
Kyle Brinkman ◽  
Yunhui Gong ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Co2 Flux ◽  
Ionic Channels ◽  
High Co2 ◽  
Spectroscopic Identification

scholarly journals High CO2 permeation flux enabled by highly interconnected three-dimensional ionic channels in selective CO2 separation membranes

2012 ◽  
Vol 5 (8) ◽  
pp. 8310 ◽  
Author(s):  
Lingling Zhang ◽  
Nansheng Xu ◽  
Xue Li ◽  
Siwei Wang ◽  
Kevin Huang ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Ionic Channels ◽  
Co2 Separation ◽  
Permeation Flux ◽  
High Co2 ◽  
Separation Membranes

scholarly journals Symmetric Aqueous Batteries of Titanium Hexacyanoferrate in Na+, K+, and Mg2+ Media

Batteries ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
Min Li ◽  
Alessandro Bina ◽  
Mariam Maisuradze ◽  
Marco Giorgetti
Keyword(s):  
Large Scale ◽  
Active Material ◽  
Three Dimensional ◽  
Negative Electrode ◽  
Ionic Channels ◽  
Manufacture Process ◽  
Order Of Magnitude ◽  
Voltage Plateau ◽  
Calculated Diffusion Coefficient ◽  
Aqueous Batteries

Symmetric batteries, in which the same active material is used for the positive and the negative electrode, simplifying the manufacture process and reducing the fabrication cost, have attracted extensive interest for large-scale stationary energy storage. In this paper, we propose a symmetric battery based on titanium hexacyanoferrate (TiHCF) with two well-separated redox peaks of Fe3+/Fe2+ and Ti4+/Ti3+ and tested it in aqueous Na-ion/ K-ion/Mg-ion electrolytes. The result shows that all the symmetric batteries exhibit a voltage plateau centered at around 0.6 V, with discharge capacity around 30 mAhg−1 at C/5. Compared to a Mg-ion electrolyte, the TiHCF symmetric batteries in Na-ion and K-ion electrolytes have better stability. The calculated diffusion coefficient of Na+, K+, and Mg2+ are in the same order of magnitude, which indicates that the three-dimensional ionic channels and interstices in the lattice of TiHCF are large enough for an efficient Na+, K+ and Mg2+ insertion and extraction.

scholarly journals Uncertainties in wind speed dependent CO<sub>2</sub> transfer velocities due to airflow distortion at anemometer sites on ships

2010 ◽  
Vol 10 (11) ◽  
pp. 5123-5133 ◽  
Author(s):  
F. Griessbaum ◽  
B. I. Moat ◽  
Y. Narita ◽  
M. J. Yelland ◽  
O. Klemm ◽  
...  
Keyword(s):  
Wind Speed ◽  
Three Dimensional ◽  
Co2 Flux ◽  
Co2 Concentration ◽  
Gas Transfer ◽  
Co2 Uptake ◽  
Flow Distortion ◽  
Simulation Code ◽  
Transfer Velocity ◽  
Concentration Difference

Abstract. Data from platforms, research vessels and merchant ships are used to estimate ocean CO2 uptake via parameterisations of the gas transfer velocity (k) and measurements of the difference between the partial pressures of CO2 in the ocean (pCO2 sw) and atmosphere (pCO2 atm) and of wind speed. Gas transfer velocities estimated using wind speed dependent parameterisations may be in error due to air flow distortion by the ship's hull and superstructure introducing biases into the measured wind speed. The effect of airflow distortion on estimates of the transfer velocity was examined by modelling the airflow around the three-dimensional geometries of the research vessels Hakuho Maru and Mirai, using the Large Eddy Simulation code GERRIS. For airflows within ±45° of the bow the maximum bias was +16%. For wind speed of 10 m s−1 to 15 m s−1, a +16% bias in wind speed would cause an overestimate in the calculated value of k of 30% to 50%, depending on which k parameterisation is used. This is due to the propagation of errors when using quadratic or cubic parameterisations. Recommendations for suitable anemometer locations on research vessels are given. The errors in transfer velocity may be much larger for typical merchant ships, as the anemometers are generally not as well-exposed as those on research vessels. Flow distortion may also introduce biases in the wind speed dependent k parameterisations themselves, since these are obtained by relating measurements of the CO2 flux to measurements of the wind speed and the CO2 concentration difference. To investigate this, flow distortion effects were estimated for three different platforms from which wind speed dependent parameterisations are published. The estimates ranged from −4% to +14% and showed that flow distortion may have a significant impact on wind speed dependent parameterisations. However, the wind biases are not large enough to explain the differences at high wind speeds in parameterisations which are based on eddy covariance and deliberate tracer methods.

scholarly journals Three-dimensional variations of atmospheric CO<sub>2</sub>: aircraft measurements and multi-transport model simulations

2011 ◽  
Vol 11 (4) ◽  
pp. 12805-12848 ◽  
Author(s):  
Y. Niwa ◽  
P. K. Patra ◽  
Y. Sawa ◽  
T. Machida ◽  
H. Matsueda ◽  
...  
Keyword(s):  
Marine Boundary Layer ◽  
Transport Model ◽  
Three Dimensional ◽  
Co2 Flux ◽  
Surface Fluxes ◽  
Dimensional Structure ◽  
Boreal Summer ◽  
Free Troposphere ◽  
Model Simulations ◽  
The North

Abstract. Numerical simulation and validation of three-dimensional structure of atmospheric carbon dioxide (CO2) is necessary for quantification of transport model uncertainty and its role on surface flux estimation by inverse modeling. Simulations of atmospheric CO2 were performed using four transport models and two sets of surface fluxes compared with an aircraft measurement dataset of Comprehensive Observation Network for Trace gases by AIrLiner (CONTRAIL), covering various latitudes, longitudes, and heights. Under this transport model intercomparison project, spatiotemporal variations of CO2 concentration for 2006–2007 were analyzed with a three-dimensional perspective. Results show that the models reasonably simulated vertical profiles and seasonal variations not only over northern latitude areas but also over the tropics and southern latitudes. From CONTRAIL measurements and model simulations, intrusion of northern CO2 in to the Southern Hemisphere, through the upper troposphere, was confirmed. Furthermore, models well simulated the vertical propagation of seasonal variation in the northern free-troposphere. However, significant model–observation discrepancies were found in Asian regions, which are attributable to uncertainty of the surface CO2 flux data. The models consistently underestimated the north-tropics mean gradient of CO2 both in the free-troposphere and marine boundary layer during boreal summer. This result suggests that the north-tropics contrast of annual mean net non-fossil CO2 flux should be greater than 2.7 Pg C yr−1 for 2007.

scholarly journals Uncertainties in wind speed dependent CO<sub>2</sub> transfer velocities due to airflow distortion at anemometer sites on ships

2009 ◽  
Vol 9 (5) ◽  
pp. 18839-18865
Author(s):  
F. Griessbaum ◽  
B. I. Moat ◽  
Y. Narita ◽  
M. J. Yelland ◽  
O. Klemm ◽  
...  
Keyword(s):  
Wind Speed ◽  
Three Dimensional ◽  
Co2 Flux ◽  
Co2 Concentration ◽  
Gas Transfer ◽  
Co2 Uptake ◽  
Flow Distortion ◽  
Simulation Code ◽  
Transfer Velocity ◽  
Concentration Difference

Abstract. Data from research vessels and merchant ships are used to estimate ocean CO2 uptake via parameterizations of the gas transfer velocity (k) and measurements of the difference between the concentration of CO2 in the ocean (pCO2sw) and atmosphere (pCO2atm) and of wind speed. Gas transfer velocities estimated using wind speed dependent parameterisations may be in error due to air flow distortion by the ship's hull and superstructure introducing biases into the measured wind speed. The effect of airflow distortion on estimates of the transfer velocity was examined by modelling the airflow around the three-dimensional geometries of the research vessels Hakuho Maru and Mirai, using the Large Eddy Simulation code GERRIS. For airflows within ±45° of the bow the maximum bias was +16%. For wind speed of 10 m s−1 to 15 m s−1, a +16% bias in wind speed would cause an overestimate in the calculated value of k of 30% to 50%, depending on which k parameterisation is used. This is due to the propagation of errors when using quadratic or cubic parameterizations. Recommendations for suitable anemometer locations on research vessels are given. The errors in transfer velocity may be much larger for typical merchant ships, as the anemometers are generally not as well-exposed as those on research vessels. Flow distortion may also introduce biases in the wind speed dependent k parameterizations themselves, since these are obtained by relating measurements of the CO2 flux to measurements of the wind speed and the CO2 concentration difference. To investigate this, flow distortion effects were estimated for three different platforms from which wind speed dependent parameterizations are published. The estimates ranged from –4% to +14% and showed that flow distortion may have a significant impact on wind speed dependent parameterizations. However, the wind biases are not large enough to explain the differences at high wind speeds in parameterizations which are based on eddy covariance and deliberate tracer methods.

scholarly journals Adjoint sensitivity of the air-sea CO<sub>2</sub> flux to ecosystem parameterization in a three-dimensional global ocean carbon cycle model

2007 ◽  
Vol 4 (2) ◽  
pp. 1377-1404 ◽  
Author(s):  
J. F. Tjiputra ◽  
A. M. E. Winguth
Keyword(s):  
Carbon Cycle ◽  
Marine Ecosystem ◽  
Three Dimensional ◽  
Co2 Flux ◽  
Global Ocean ◽  
Ecosystem Structure ◽  
Cycle Model ◽  
Ocean Carbon Cycle ◽  
Carbon Cycle Model ◽  
Ocean Carbon

Abstract. The regional sensitivity of air-sea CO2 flux to ecosystem components and parameters in a three-dimensional ocean carbon cycle model is estimated using an adjoint model. Adjoint sensitivities to the global air-sea CO2 flux reveal that the biological component of the model is significant in the high latitudes of both hemispheres and in the Equatorial Pacific. More detailed analysis indicates that zooplankton grazing activity plays a major role in the carbon exchange in the above regions. The herbivores' ingestion parameter in the model regulates the flux of remineralized (i.e. regenerated) biogenic nutrients; thus, substantially controls the biological production and the concentration of dissolved inorganic carbon (DIC) in the euphotic zone. Over a 10-year period, reducing the herbivores' ingestion parameter in the model by 25% could increase the global uptake of atmospheric carbon by 6 Pg C. Thus, climate induced changes in the marine ecosystem structure are of importance for the future uptake of atmospheric CO2.

scholarly journals On the resolution requirements for accurately representing interactions between plant canopy structure and function in three-dimensional leaf-resolving models

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Brian N Bailey ◽  
Eric R Kent
Keyword(s):  
Canopy Structure ◽  
Three Dimensional ◽  
Co2 Flux ◽  
Diffuse Radiation ◽  
Structure And Function ◽  
Plant Canopy ◽  
Model Errors ◽  
Plant Structure ◽  
And Function ◽  
The Impact

Abstract While functional–structural plant models (FSPMs) have been proposed as a tool for better analysing and predicting interactions between plant structure and function, it is still unclear as to what spatial resolution is required to adequately resolve such interactions. Shadows cast by neighbouring leaves in a plant canopy create extremely large spatial gradients in absorbed radiation at the sub-leaf scale, which are usually not fully resolved in ‘leaf-resolving’ plant models. This failure to resolve sharp radiative gradients can propagate to other dependent biophysical models, and result in dramatic overprediction of whole-plant and -canopy fluxes with errors significantly higher than that of a statistical ‘big leaf’ or turbid medium model. Under-resolving radiative gradients creates a diffusive effect in the probability distribution of absorbed radiation, and smears out the effect of canopy structure, effectively undermining the original goal of a leaf-resolving model. Errors in whole-canopy fluxes of photosynthesis increased approximately linearly with increasing LAI, projected area fraction G, and decreased logarithmically as the fraction of incoming diffuse radiation was increased. When only one discrete element per leaf was used, errors in whole-canopy net CO2 flux could be in excess of 100 %. Errors due to sub-leaf resolution decreased exponentially as the number of elements per leaf was increased. These results prompt closer consideration of the impact of sub-leaf resolution on model errors, which is likely to prompt an increase in resolution relative to current common practice.

High CO2 flux measurements in volcanic and geothermal areas, methodologies and results

2001 ◽  
Vol 177 (1-2) ◽  
pp. 1 ◽  
Author(s):  
Deborah Bergfeld ◽  
Fraser Goff ◽  
Patric Allard
Keyword(s):  
Co2 Flux ◽  
High Co2 ◽  
Flux Measurements
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