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Background: A critical parameter of extracorporeal CO 2 removal (ECCO 2 R) applications is the CO 2 removal rate (VCO 2 ). Low-flow venovenous extracorporeal support with large-size membrane lung remains undefined. This study aimed to evaluate the VCO 2 of a low-flow ECCO 2 R with large-size membrane lung using a renal replacement therapy platform in an experimental animal model., Methods: Twelve healthy pigs were placed under mechanical ventilation and connected to an ECCO 2 R-CRRT system (surface area = 1.8 m 2 ; OMNIset®, BBraun, Germany). Respiratory settings were reduced to induce two degrees of hypercapnia. VCO 2 was recorded under different combinations of PaCO 2 (50-69 or 70-89 mm Hg), extracorporeal blood flow (ECBF; 200 or 350 mL/min), and gas flow (4, 6, or 10 L/min)., Results: VCO 2 increased with ECBF at all three gas flow rates. In severe hypercapnia, the increase in sweep gas flow from 4 to 10 L/min increased VCO 2 from 86.38 ± 7.08 to 96.50 ± 8.71 mL/min at an ECBF of 350 mL/min, whereas at ECBF of 200 mL/min, any increase was less effective. But in mild hypercapnia, the increase in sweep gas flow result in significantly increased VCO 2 at two ECBF. VCO 2 increased with PaCO 2 from 50-69 to 70-89 mm Hg at an ECBF of 350 mL/min, but not at ECBF of 200 mL/min. Post-membrane lung PCO 2 levels were similar for different levels of premembrane lung PCO 2 (p = 0.08), highlighting the gas exchange diffusion efficacy of the membrane lung in gas exchange diffusion. In severe hypercapnia, the reduction of PaCO 2 elevated from 11.5% to 19.6% with ECBF increase only at a high gas flow of 10 L/min (p < 0.05) and increase of gas flow significantly reduced PaCO 2 only at a high ECBF of 350 mL/min (p < 0.05)., Conclusions: Low-flow venovenous extracorporeal ECCO 2 R-CRRT with large-size membrane lung is more efficient with the increase of ECBF, sweep gas flow rate, and the degree of hypercapnia. The influence of sweep gas flow on VCO 2 depends on the ECBF and degree of hypercapnia. Higher ECBF and gas flow should be chosen to reverse severe hypercapnia., (© 2024 The Authors. Artificial Organs published by International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

Microbial electrosynthesis (MES) constitutes a bioelectrochemical process where bacteria uptake electrons extracellularly from a polarized electrode to incorporate them into their anabolic metabolism. However, the efficiency of current MES reactor designs can be lower than expected due to limitations regarding electron transfer and mass transport. One of the most promising bioreactor configurations to overcome these bottlenecks is the Microbial Electrochemical Fluidized Bed Reactor (ME-FBR). In this study, microbial CO 2 fixation is investigated for the first time in a ME-FBR operated as a 3-phase reactor (solid-liquid-gas). An electroconductive carbon bed, acting as a working electrode, was fluidized with gas and polarized at different potentials (-0.6, -0.8 and -1 V vs. Ag/AgCl) so it could act as an electron donor (biocathode). Under these potentials, CO 2 fixation and electron transfer were evaluated. Autotrophic electroactive microorganisms from anaerobic wastewater were enriched in a ME-FBR in the presence of 2-bromoethanosulfonic acid (BES) to inhibit the growth of methanogens. Cyclic voltammetry analysis revealed interaction between the microorganisms and the cathode. Furthermore, volatile fatty acids like propionate, formate and acetate were detected in the culture supernatant. Acetate production had a maximum rate of ca. 1 g L -1  day -1 . Planktonic cell biomass was produced under continuous culture at values as high as ca. 0.7 g L -1 dry weight. Overall, this study demonstrates the feasibility of employing a fluidized electrode with gaseous substrates and electricity as the energy source for generating biomass and carboxylic acids., (© 2023 The Authors. Microbial Biotechnology published by Applied Microbiology International and John Wiley & Sons Ltd.)

This review paper explores the diverse applications of polylactide or polylactic acid (PLA) and its contributions to environmental sustainability. It delves into the synthesis, properties, and numerous applications of PLA, accompanied by illustrative examples demonstrating its ability to reduce carbon emissions. The environmentally friendly characteristics of PLA, coupled with its versatility, make it a vital player in the ongoing efforts to combat climate change. PLA generally requires lower extrusion temperatures than other 3D printing materials, such as ABS (Acrylonitrile Butadiene Styrene). Lower extrusion temperatures lead to reduced energy consumption during the printing process thus the reduction in carbon dioxide emissions during production. Plants, such as corn and sugarcane, play a crucial role in absorbing carbon dioxide from the atmosphere during their growth cycle. When these plants are utilized to produce PLA, the captured CO2 remains sequestered within the plastic material. This contributes to offsetting CO2 emissions from other sources. In conclusion, the usage of PLA has demonstrated positive contributions to the reduction of carbon dioxide emissions through its renewable sourcing, lower extrusion temperatures, lower dependence on fossil fuels, reduced greenhouse gas emissions during production, biodegradability, and participation in a closed carbon cycle. [ABSTRACT FROM AUTHOR]

Time series of radiative cooling of the upper mesosphere and lower thermosphere (UMLT) by carbon dioxide (CO2) are examined for evidence of trends over 20 years. Radiative cooling rates in K day−1 provided by the SABER instrument are converted to time series of infrared power radiated from three distinct layers between 0.1 hPa and 0.0001 hPa (65–105 km). Linear regression against time and a predictor for solar variability provides estimates of the trend in exiting longwave radiation (ELR) from these layers. Trends in ELR are not significantly different from zero at 95% or 99% confidence in each layer. These results demonstrate energy conservation in the UMLT on decadal time scales and show that the UMLT continues to radiate the same amount of energy it receives despite cooling and contracting over two decades. These results are enabled by the long‐term stability of the SABER instrument calibration. Plain Language Summary: The Earth's upper mesosphere and lower thermosphere (UMLT) is the region between approximately 65 and 105 km in altitude. Infrared radiation emitted by CO2 is a fundamental component of the energy budget of the UMLT. Carbon dioxide (CO2) is increasing in this region. The amount of infrared energy emitted by CO2, over time, must balance the amount of energy from sunlight that is absorbed in the UMLT. Observations from orbiting satellites over the past two decades have shown that the temperature in the UMLT is decreasing due to the increasing CO2. A decreasing temperature implies a decrease in infrared energy emitted by an object. Energy conservation, however, requires that the amount of infrared energy radiated from the UMLT balance the amount of energy received, regardless of the temperature. In this paper we show that there is no significant long‐term change with time (i.e., zero trend) in the infrared energy emitted from the UMLT even though the UMLT temperature has been decreasing for the last 20 years (and longer) due to increasing CO2. This result confirms that energy is conserved in a cooling and contracting UMLT. Key Points: Time series of infrared power (W) radiated by CO2 from the upper mesosphere & lower thermosphere (UMLT) are developedTrends in radiated power are not different from zero at 95% or 99% confidence in the three layers examined between 0.1 and 0.0001 hPaIncreasing CO2 reduces the UMLT temperature while radiating the same amount of energy over time, thus conserving energy [ABSTRACT FROM AUTHOR]

The global energy system is in transition. It is attempting to reach net‐zero greenhouse gas emissions by 2050. The systemic changes mean that the role of bioenergy will change. The potential of bioenergy to make a flexible contribution to the energy system is key for the achievement of global emission reduction ambitions and the functioning of the low‐carbon energy system and economy. As the volume of sustainably available biomass resources is limited, defining the contributions from bioenergy to a low‐carbon energy system and finding balances – and ideally synergies – between the different possible energy and climate system services that biomass can provide will be very important. The recognized system services include, among others, the flexible operation of bioenergy plants to integrate variable renewable energy sources and to provide negative carbon dioxide (CO2) emissions. Interest in flexible operation of bioenergy value chains, bioenergy with carbon capture and utilization as well as synergies with renewable hydrogen‐based value chains has increased recently. The objective of this paper is to present a holistic definition of flexible bioenergy as a system service based on the work conducted in International Energy Agency (IEA) Bioenergy Technology Collaboration Programme's Task 44 Flexible Bioenergy and System Integration, and to provide some practical examples. The paper also presents the different bioenergy system services and considers their definitions and interactions, as this is important in energy system design. The definition of flexible bioenergy shows that the flexibility provision from bioenergy goes far beyond the traditional definition of providing short‐term flexibility in the power sector. Indicators to demonstrate the value of services as well as further quantitative assessment of synergies and trade‐offs are needed to valorize the different services from bioenergy and create viable business cases. [ABSTRACT FROM AUTHOR]

We present a cost model for implementing a deployment scale effort for conducting ocean iron fertilization (OIF) for marine‐based carbon dioxide removal (CDR). The model incorporates basic oceanographic parameters critical for estimating the effective export of newly fixed CO2 into biomass that is stimulated by Fe addition to an Fe‐limited region of the Southern Ocean. Estimated costs can vary by nearly 100‐fold between best‐case and worst‐case scenarios, with best‐case values of $7/net tonne C captured versus worst‐case $1,500/net tonne C captured, without accounting for verification costs. Primary oceanographic factors that influence cost are the net primary productivity increases achieved via OIF, the amount of C exported into the deep ocean, and the amount of CO2 ventilated back to the atmosphere. The model compares ship‐based versus aerial delivery of Fe to the ocean, and estimates aerial delivery can be 30%–40% more cost effective; however, the specific requirements for aerial delivery require additional research and development. The model also estimates costs associated with verification and environmental monitoring of OIF. These costs increase $/net tonne C captured by 3–4‐fold. Best, intermediate, and worst cases for aerial delivery and ship delivery are $21, $83, $2,033, and $24, $94, $4,691, respectively, inclusive of verification costs. The primary goal of this model is to demonstrate the variability in cost of OIF as a CDR method, and to better understand where additional research is needed to determine the major factors that may make OIF a tractable, nature‐based CDR method. Plain Language Summary: This paper presents a basic cost model for undertaking ocean iron fertilization (OIF) as a means of removing carbon dioxide from the atmosphere. It presents a simple application scenario that compares two different modes for delivering iron to the ocean, plane‐based and ship‐based, and estimates costs associated with verification of carbon export into the deep ocean, as well as assessing the environmental changes that may occur as result. Key findings are that, in terms of USD/tonnes carbon exported, OIF can be at the lower cost end (

The emission of greenhouse gases (GHG), particularly carbon dioxide (CO2), within the atmosphere poses serious threats to society and the environment. In this paper, we examine the effect of carbon dioxide (CO2) emissions on the association between corporate social responsibility (CSR) and stock valuation. Using a sample of listed non‐financial US firms from 2002 through 2018, we find that CO2 emission plays a moderating role in reshaping the CSR‐stock valuation nexus. Further analysis showed that our results are robust for using alternate proxies of CSR, CO2, additional control and methods to alleviate endogeneity concerns. Additionally, we explored how increasing carbon footprints reshape this association only for firms with strong governance structures. Overall, our results indicate that the positive impact of CSR on stock valuation is overlaid by corporate CO2 emission. The practical and theoretical insights of this study were explored. [ABSTRACT FROM AUTHOR]

The electroreduction of CO2 to high‐value products is a promising approach for achieving carbon neutrality. Among these products, formic acid stands out as having the most potential for industrialization due to its optimal economic value in terms of consumption and output. In recent years, the Faraday efficiency of formic acid from CO2 electroreduction has reached 90~100 %. However, this high selectivity cannot be maintained for extended periods under high currents to meet industrial requirements. This paper reviews excellent work from the perspective of catalyst stability, summarizing and discussing the performance of typical catalysts. Strategies for preparing stable and highly active catalysts are also briefly described. This review may offer a useful data reference and valuable guidance for the future design of long‐stability catalysts. [ABSTRACT FROM AUTHOR]

A carbon paper‐based gas diffusion electrode (GDE) is used with a bismuth(III) subcarbonate active catalyst phase for the electrochemical reduction of CO2 in a gas/electrolyte flow‐by configuration electrolyser at high current density. It is demonstrated that in this configuration, the gas and catholyte phases recombine to form K2CO3/KHCO3 precipitates to an extent that after electrolyses, vast amount of K+ ions is found by EDX mapping in the entire GDE structure. The fact that the entirety of the GDE gets wetted during electrolysis should, however, not be interpreted as a sign of flooding of the catalyst layer, since electrolyte perspiring through the GDE can largely be removed with the outflow gas, and the efficiency of electrolysis (toward the selective production of formate) can thus be maintained high for several hours. For a full spatial scale quantitative monitoring of electrolyte penetration into the GDE, (relying on K+ ions as tracer) the method of inductively coupled plasma–mass spectrometry (ICP–MS) assisted energy dispersive X‐ray (EDX) tomography is introduced. This new, cheap and robust tomography of non‐uniform aspect ratio has a large planar span that comprises the entire GDE surface area and a submicrometer depth resolution, hence it can provide quantitative information about the amount and distribution of K+ remnants inside the GDE structure, in three dimensions. [ABSTRACT FROM AUTHOR]

CO2 huff and puff is a widely used enhanced oil recovery method in many oil fields, but its implementations in shale fields is scarce. This paper reports trials of CO2 huff and puff in a shale field in China. Laboratory studies revealed that CO2 effectively reduced oil viscosity, increased oil volume, and improved oil recovery under miscible conditions. For the three wells that received CO2 huff and puff treatments, one well showed satisfactory results, while the other two wells demonstrated poor economics. Discussions and recommendations are made based on field experiences. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The process of preparing methanol from carbon dioxide is one of the ways to solve the environmental problems caused by greenhouse gases, the problem of fossil energy depletion, and the problem of fuel exhaust emissions. However, after decades of development, the process of preparing methanol from carbon dioxide is still unable to achieve large‐scale industrialization. This critical review sharply points out the problems and obstacles that need to be solved urgently on the industrialization road of carbon dioxide methanol preparation process and summarizes its progress. The problems faced by the methanol production industry from carbon dioxide are first the thermodynamic constraints, second the lower reaction rate and conversion effect, and finally the energy loss. In order to solve these problems, this paper first introduces the active sites, structural effects, and dynamic changes of copper‐based catalysts, as well as the unique reaction mechanism and doping modification of indium‐based catalysts. Zinc and zirconium promoters and some metal oxide supports can form unique interactions with active components to improve the catalytic performance of the catalyst. Next, various kinetic models and applications of methanol production from carbon dioxide are summarized, which is an important bridge linking laboratory and industrialization; the advantages and disadvantages of fixed bed reactor and paddle reactor were compared. Finally, the full text is summarized and prospected. [ABSTRACT FROM AUTHOR]

As carbon monoxide has a broad spectrum of biological activities, its production by plasma is a significant advantage in medicine. This paper presents a comparative study of the CO production of two plasma jets: a MHz‐jet and a kHz‐jet. Both were fed with a helium gas with CO2 ${\text{CO}}_{2}$ admixture (0%–1%). CO was produced by CO2 ${\text{CO}}_{2}$ dissociation and its maximal concentration was hundreds of parts per million, which is safe for clinical applications. For the same specific energy input, the CO production was more efficient for the kHz‐jet than the MHz‐jet. Both had antibacterial properties on Escherichia coli, and the addition of CO2 ${\text{CO}}_{2}$ improved them for the MHz‐jet, while it reduced them for the kHz‐jet. [ABSTRACT FROM AUTHOR]

Across Europe, countries are reducing CO2 emissions and energy demand by lowering the temperature in public office buildings. These measures affect men and women unequally because the latter prefer and, indeed, perform better under higher temperatures than the standard temperature. Lowering the temperature thus further increases an already existing inequality. We show that the philosophical literature on discrimination provides an interesting theoretical approach to understanding such measures. On prominent understandings of what discrimination is, the policy would be considered direct discrimination against women if it could be shown to reflect a broader inattentiveness to the needs of women in society. Alternatively, and more straightforwardly, the policies can be considered indirect discrimination because of their disparate effects on men and women. The final part of the paper shows that the policies are also wrong for the reasons it is often argued that discrimination is wrong—to wit, that it harms or disrespects those who are discriminated against. The final section suggests a range of measures to offset the discriminatory aspects of the policy. [ABSTRACT FROM AUTHOR]

Multiphysics inversion exploits different types of geophysical data that often complement each other and aims to improve overall imaging resolution and reduce uncertainties in geophysical interpretation. Despite the advantages, traditional multiphysics inversion is challenging because it requires a large amount of computational time and intensive human interactions for preprocessing data and finding trade‐off parameters. These issues make it nearly impossible for traditional multiphysics inversion to be applied as a real‐time monitoring tool for geological carbon storage. In this paper, we present a deep learning (DL) multiphysics network for imaging CO2 saturation in real time. The multiphysics network consists of three encoders for analysing seismic, electromagnetic and gravity data and shares one decoder for combining imaging capabilities of the different geophysical data for better predicting CO2 saturation. The network is trained on pairs of CO2 label models and multiphysics data so that it can directly image CO2 saturation. We use the bootstrap aggregating method to enhance the imaging accuracy and estimate uncertainties associated with CO2 saturation images. Using realistic CO2 label models and multiphysics data derived from the Kimberlina CO2 storage model, we evaluate the performance of the deep learning multiphysics network and compare its imaging results to those from the deep learning single‐physics networks. Our modelling experiments show that the deep learning multiphysics network for seismic, electromagnetic, and gravity data not only improves the imaging accuracy but also reduces uncertainties associated with CO2 saturation images. Our results also suggest that the deep learning multiphysics network for the non‐seismic data (i.e., electromagnetic and gravity) can be used as an effective low‐cost monitoring tool in between regular seismic monitoring. [ABSTRACT FROM AUTHOR]

Earth experienced the strongest geomagnetic storm in 20 years over 10–13 May 2024. The Ap and Dst geomagnetic indices were 273 and −291.94 nT on 11 May. The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on the Thermosphere‐Ionosphere‐Mesosphere Energetics and Dynamics satellite observed significant enhancement in thermospheric infrared emission at 15, 5.3, 4.3, and 1.27 μm. On 11 May the daily global power radiated by nitric oxide (NO) at 5.3 μm was 1.41 TW and by carbon dioxide (CO2) at 15 μm was 1.35 TW. These are the largest single day power values observed by SABER in 22 years and the first time the daily power radiated by NO exceeded that of CO2. The total infrared power (above background) radiated during the storm was 2.64 TW (2.28 × 1017 J). Significant enhancement in limb radiance observed at 4.3 μm (to 250 km tangent height) is likely indicative of NO + formation during the storm. Plain Language Summary: The layer of Earth's atmosphere above 100 km is referred to as the "thermosphere" and can be thought of as the boundary between the space environment above it and the atmosphere below it. In early May 2024, an active sunspot ejected a significant amount of charged particles (protons and electrons) within a strong magnetic field toward Earth. This "coronal mass ejection" or CME encountered Earth's high atmosphere 10–13 May, causing a significant "geomagnetic storm" that significantly heated the thermosphere and modified its chemical composition. The effects of this storm were observed by the SABER instrument which is flying on the NASA Thermosphere‐Ionosphere‐Mesosphere Energetics and Dynamics satellite. Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) observes infrared light emitted by carbon dioxide, nitric oxide, molecular oxygen, and ionized nitric oxide produced during the storm. The 10–13 May storm caused the global average infrared radiation levels to increase by nearly a factor of 10 at some wavelengths in 1 day. The storm and the infrared radiation levels dissipated back to pre‐storm levels over the next 2 days. This storm was the third strongest in terms the power (2.64 trillion watts) radiated by the thermosphere in the past 22 years observed by SABER. The observed enhancements in infrared radiation at multiple wavelengths offer the opportunity to more fully understand how the Sun interacts with and influences Earth's highest atmosphere. Key Points: The daily Ap (273 nT) and Dst (−291.94 nT) indexes on 11 May 2024 were the largest since the launch of the Thermosphere‐Ionosphere‐Mesosphere Energetics and Dynamics (TIMED) satellite in December 2001The power radiated 11 May by NO and CO2 exceeded 1 TW each and the NO power (1.41 TW) exceeded the CO2 power (1.35 TW) for the first timeTotal storm radiated power, above background, is 2.64 TW (2.28 × 1017 J), making it the third strongest storm during the TIMED era [ABSTRACT FROM AUTHOR]

Utilizing renewable electricity for the electrocatalytic conversion of CO2 into alcohols represents a promising avenue for generating value‐added fuels and achieving carbon neutrality. Recently, there has been growing scientific interest in achieving high‐efficiency conversion of CO2 to alcohols, with significant advancements made in mechanism understanding, reactor design, catalyst development, and more. Herein, a thorough examination of the latest advances in electrocatalytic CO2 reduction reaction (CO2RR) to alcohols is provided. General mechanisms and pathways of electrocatalytic conversion of CO2‐to‐alcohols are systematically illustrated. Subsequently, electrolyzer configurations, electrolytes, and electrocatalysts employed in CO2RR are summarized. After that, critical operating parameters (e.g., reaction pressure, temperature, and pH) that would significantly influence the CO2RR process are also analyzed. Finally, the review addresses challenges and offers perspectives in this field to guide future studies aimed at advancing CO2‐to‐alcohols conversion technologies. [ABSTRACT FROM AUTHOR]

Twenty‐two years (2002–2023) of infrared radiative cooling rate data derived from the SABER instrument on the NASA TIMED satellite are presented. Global daily and global annual infrared power (Watts, W) emitted by nitric oxide (NO) and carbon dioxide (CO2) illustrate the variability of the geospace environment on timescales from days to decades. The 11‐year solar cycle (SC) is evident in the global power data and in vertical profiles of infrared cooling rates (nW/m3). The global annual power radiated by NO and CO2 are larger in 2023 than at any time since 2003 and 2002, respectively. The to‐date peak in NO infrared power in SC 25 is larger than in SC 24, is comparable to SC 20, but is less than in SCs 18–19 and 21–23. Two geomagnetic storms in 2023 radiated more than 1 TW and are in the top 10 strongest storms observed by SABER. Plain Language Summary: SABER is an instrument on the NASA TIMED satellite, launched in December 2001, and is still operating nominally in 2024. SABER measures the amount of infrared energy emitted by the nitric oxide (NO) molecule and the carbon dioxide (CO2) molecule from Earth's thermosphere, the region of atmosphere above 100 km altitude. These measurements are used to derive the amount of power (Watts) radiated globally by these two molecules on daily to annual timescales. The infrared power data is then analyzed to determine its variability in the lower thermosphere from daily to decadal time scales. Of particular interest is the influence of the well‐known 11‐year cycle of solar activity which is readily evident in the infrared power data. SABER also observes the effects of geomagnetic storms, identifying two strong storms in 2023 that each produced over 1 TW of infrared power. Key Points: SABER on TIMED has observed infrared radiation from the thermosphere since January 2002, for 22 years, the equivalent of two solar cyclesGlobal annual infrared power radiated by NO and CO2 are larger in 2023 than any time since 2003 and 2002, respectivelyTwo geomagnetic storms in 2023 exceeded 1 TW of radiated energy, above background, and are in the top 10 strongest storms observed [ABSTRACT FROM AUTHOR]

Geologic storage of CO2 and H2 are climate‐positive techniques for meeting the energy transition. While similar formations could be considered for both gases, the flow dynamics could differ due to differences in their thermophysical properties. We conduct a rigorous pore‐scale study of water/CO2 and water/H2 systems at relevant reservoir conditions in a Bentheimer rock sample using the lattice Boltzmann method to quantify the effects of capillary, viscous, inertial, and wetting forces during gas invasion. At similar conditions, H2 invasion is weaker compared to CO2 due to unfavorable viscosity ratios. Increasing flow rate, however, increases the breakthrough saturation for both gas systems in the range of capillary numbers studied. At isolated conditions of flow rate, viscosity ratio, and wettability, local inertial effects are found to be critical and show consistent increase in the invaded gas saturation. The effect of inertial forces persits for both gases across all field conditions tested. Plain Language Summary: We present a numerical investigation at the pore‐scale to contrast the dynamics of fluid transport for water/CO2 and water/H2 systems at reservoir conditions. Understanding such dynamics is critical to evaluate the feasibility of the geologic storage of these gases (long‐term storage of CO2 and short‐term, periodic storage of H2), which are being researched as green techniques for mitigating climate change. Through a systematic analysis, we demonstrate the importance of pore‐scale mechanisms like local inertial effects which are not well studied in the literature. These effects cause fast fluid motion and consistently allow more fluid to be injected in the rock independently from the other physical effects. Such effects should be carefully accounted for when modeling these systems for large‐scale gas storage. Key Points: At similar reservoir conditions, invasion of H2 is found to be weaker as opposed to CO2 due to unfavorable viscosity ratiosAmong the tested reservoir scenarios, P/T conditions for the saline aquifer provided the largest amount of invaded gas until breakthroughLocal inertial effects control the dynamics of the invading gas across different wettability, viscosity ratios, and capillary numbers [ABSTRACT FROM AUTHOR]

The photosynthetic amoeba, Paulinella provides a recent (ca. 120 Mya) example of primary plastid endosymbiosis. Given the extensive data demonstrating host lineage‐driven endosymbiont integration, we analysed nuclear genome and transcriptome data to investigate mechanisms that may have evolved in Paulinella micropora KR01 (hereinafter, KR01) to maintain photosynthetic function in the novel organelle, the chromatophore. The chromatophore is of α‐cyanobacterial provenance and has undergone massive gene loss due to Muller's ratchet, but still retains genes that encode the ancestral α‐carboxysome and the shell carbonic anhydrase, two critical components of the biophysical CO2 concentrating mechanism (CCM) in cyanobacteria. We identified KR01 nuclear genes potentially involved in the CCM that arose via duplication and divergence and are upregulated in response to high light and downregulated under elevated CO2. We speculate that these genes may comprise a novel CO2 delivery system (i.e., a biochemical CCM) to promote the turnover of the RuBisCO carboxylation reaction and counteract photorespiration. We posit that KR01 has an inefficient photorespiratory system that cannot fully recycle the C2 product of RuBisCO oxygenation back to the Calvin‐Benson cycle. Nonetheless, both these systems appear to be sufficient to allow Paulinella to persist in environments dominated by faster‐growing phototrophs. [ABSTRACT FROM AUTHOR]

This document is a response to concerns raised by Reershemius and Suhrhoff regarding a study conducted by Kantola et al. The authors of the response acknowledge that Reershemius and Suhrhoff did not find any faults with the derivation in the paper, which they state are factually true. They also mention that Reershemius and Suhrhoff arrived at a similar result in their own unpublished work. The response addresses specific implementation details raised by Reershemius and Suhrhoff and argues that these concerns lack merit. The authors appreciate the constructive engagement and transparency of data. [Extracted from the article]

Ocean mesoscale flows significantly influence nutrient distribution and biological productivity, yet the scarcity of eddy‐permitting observational data sets and climate modeling hinders understanding their role in carbon sequestration. Using an eddy‐resolving global simulation, this study investigates the significance of ocean mesoscales in air‐sea carbon dioxide (CO2) exchange. Results show over 30% of CO2 flux variance in energetic regions attributed to flows with horizontal scales smaller than 2°. Mesoscale flows can drive a cumulative CO2 flux that is either a net carbon sink or source depending on region, with magnitudes on the order of 105 tonnes of carbon per year. Variations in this mesoscale‐related CO2 flux are correlated with local relative vorticity and the background gradient of ocean partial pressure of CO2. This analysis underscores the importance of considering ocean mesoscales in monitoring carbon flux, highlighting the need to explore the influence of increasing eddy activity on carbon uptake in a changing climate. Plain Language Summary: This study investigates the influence of ocean flows with horizontal scales of tens to hundreds of kilometers (called mesoscale flows) on the exchange of carbon dioxide between the ocean and the atmosphere using a state‐of‐the‐art high resolution global simulation. It is shown that in certain parts of the ocean, more than 30% of the variability in carbon dioxide exchange at the ocean surface is linked to these relatively small‐scale ocean motions. It is further revealed that mesoscale flows can lead to a significant gain or loss of carbon from the ocean at the regional level, and that depends on how the flow is oriented with respect to the background distribution of carbon in the ocean. Gaining a better understanding of how the mesoscale flow features influence air‐sea carbon dioxide exchange is crucial for understanding the ocean's role in the carbon cycle and its ability to absorb and store carbon in a changing climate. Key Points: Over 30% of air‐sea CO2 flux variability is attributed to ocean spatial scales smaller than 2° in eddy‐rich regionsThe cumulative mesoscale‐induced CO2 flux is on the order of 105 tonnes of carbon per yearMesoscale‐related CO2 flux is governed by both relative vorticity and the background gradient of partial pressure of CO2 [ABSTRACT FROM AUTHOR]

Incorporating large amounts of woody biomass into soil, such as in whole orchard recycling (WOR), can promote carbon sequestration, nutrient recycling, and ecosystem health in agricultural fields. Yet uncertainty regarding the effects of WOR on soil carbon (C) and nitrogen (N) dynamics influences management decisions. The objective of this research was to evaluate the effects of woodchip (WC) size and interaction with N fertilization on carbon dioxide (CO2) and nitrous oxide (N2O) emissions. An 8‐month incubation experiment incorporating WC (4% w/w, equivalent to ∼40 tons per acre) in four sieved sizes (0.2–1.6, 1.6–3.2, 3.2–6.4, and 6.4–12.7 mm) with and without N applications was conducted. All treatments with WC showed that CO2 emission peaked within the first week, then decreased drastically afterward. The CO2 peak delayed as the peak value decreased (WC size increased). The finest WC (<1.6 mm) yielded the lowest total CO2 emissions and resulted in the greatest increase in soil C at the end of incubation. Nitrogen application reduced total CO2 emissions by 1% in the smallest WC size and by 8%–9% for those larger than 1.6 mm. The N2O emissions spiked following each fertilizer application with lowest total emissions from the smallest WC size, suggesting substantial N immobilization. The results imply that larger WC sizes can delay C mineralization and reduce initial N immobilization risks, but the smallest WC size may have stabilized and increased soil organic carbon. This research increased our understanding on WC mineralization that can be used in WOR management. Core Ideas: There is a significant interaction between woodchip size and N application on both CO2 and N2O emissions.Smallest woodchip size gave highest initial CO2 emissions, but lowest total loss while increasing soil organic carbon.N application with woodchips resulted in significantly lower CO2 emissions.Woodchip size showed different impact on peak N2O emissions with time but no impact on total loss and soil N.Larger woodchip sizes showed delay in C mineralization, minimizing the initial N immobilization risk. [ABSTRACT FROM AUTHOR]

N‐coordinated Ni sites (NiNx) are effective catalysts for the electrochemical reduction of CO2 to CO. In most researches, modulating the coordination environment of Ni atoms is focused on to improve electrochemical CO2 reduction (ECR) performance. However, the influence of the carbon substrate's structure on the intrinsic activity of NiNx is seldom investigated. The highly curved surface of carbon nanotubes (CNT) may provide a unique curvature effect on NiNx. It is found that the Ni residues in CNT can be atomized to form NiNx sites on the surface of CNT (Ni‐N/CNT@covalent triazine framework [CTF]) through high‐temperature pyrolysis, using a soluble CTF nanosheet as N precursor. The π‐conjugated and ultrathin 2D structure of CTF enables closer interfacial contact between CTF and CNT, which avoids the formation of a thick carbon layer to maximize the curvature effect. Theoretical data reveal that the NiN3 configuration may act as a highly active ECR site, and the curvature effect from CNT can further tune the electronic structure of NiN3, thus improving the ECR kinetics. The Ni‐N/CNT@CTF‐based flow‐cell electrolyzer exhibits a jCO of 201 mA cm−2 at −0.9 V with a high FECO of 98%. [ABSTRACT FROM AUTHOR]

In current research, achieving carbon neutrality has become a primary focus through the utilization of various conversion technologies that transform carbon dioxide (CO2) into valuable chemicals or fuels. Covalent organic frameworks (COFs), as emerging crystalline organic polymers, offer distinct advantages in CO2 conversion compared to other materials. These advantages include controllable nanoscale pores, predefined functional units, editable framework structures, and rich conjugated systems. The unique characteristics of COFs make them highly promising electrocatalysts for CO2 conversion. This review provides a comprehensive overview of pioneering works and recent research on the utilization of COF‐based materials as electrocatalysts for electrochemical CO2 reduction reaction. This review offers a comprehensive analysis of the design principles for various reactive sites, skeleton structures, pore functionalities, 3D frameworks, morphologies, and composite materials of COFs, aiming to enhance electrocatalysis. Finally, this review presents some recommendations for material design, reaction mechanisms, and theoretical computations to enhance the understanding of reaction mechanisms further and facilitate the design of high‐performance COF‐based electrocatalysts. [ABSTRACT FROM AUTHOR]

Conversion of carbon dioxide (CO2) to valuable chemicals and feedstocks through electrochemical reduction holds promise for achieving carbon neutrality and mitigating global warming. C2+ products are of interest due to their higher economic value. Since the CO2 to C2+ conversion process involves multiple steps, tandem catalytic strategies are commonly employed in the design of electrochemical CO2 reduction reaction (CO2RR) catalysts and systems/reactors. Among the diverse catalysts that are capable of reducing CO2 to CO, Cu stands out for more efficiently further converting CO to C2+ products. In this review, the emerging Cu‐based tandem catalysts and their impact on CO2RR performance, focusing on three positional relationships are summarized. It delves into the integration of tandem catalytic strategies into membrane electrolyzers, utilizing catalyst‐coated substrate (CCS) and catalyst‐coated membrane (CCM) technologies. Several typical examples are presented to illustrate this integration. Finally, the challenges and prospects of applying tandem strategies in the development of CO2RR catalysts/systems, as well as their device‐level implementation are indicated. [ABSTRACT FROM AUTHOR]

To reach their net‐zero targets, countries will have to compensate hard‐to‐abate CO2 emissions through carbon dioxide removal (CDR). Yet, current assessments rarely include socio‐cultural or institutional aspects or fail to contextualize CDR options for implementation. Here we present a context‐specific feasibility assessment of CDR options for the example of Germany. We assess 14 CDR options, including three chemical carbon capture options, six options for bioenergy combined with carbon capture and storage (BECCS), and five options that aim to increase ecosystem carbon uptake. The assessment addresses technological, economic, environmental, institutional, social‐cultural and systemic considerations using a traffic‐light system to evaluate implementation opportunities and hurdles. We find that in Germany CDR options like cover crops or seagrass restoration currently face comparably low implementation hurdles in terms of technological, economic, or environmental feasibility and low institutional or social opposition but show comparably small CO2 removal potentials. In contrast, some BECCS options that show high CDR potentials face significant techno‐economic, societal and institutional hurdles when it comes to the geological storage of CO2. While a combination of CDR options is likely required to meet the net‐zero target in Germany, the current climate protection law includes a limited set of options. Our analysis aims to provide comprehensive information on CDR hurdles and possibilities for Germany for use in further research on CDR options, climate, and energy scenario development, as well as an effective decision support basis for various actors. Plain Language Summary: Countries aiming to achieve net‐zero emissions will have to remove the remaining carbon dioxide from the atmosphere through carbon dioxide removal (CDR). However, current assessments of CDR options rarely consider socio‐cultural or institutional aspects or set the CDR options in the specific context of their implementation. In this study, researchers conducted the first context‐specific feasibility assessment of CDR options in Germany, considering six dimensions, including technological, economic, environmental, institutional, and social‐cultural aspects. The study assessed 14 CDR options, including chemical carbon capture options, bioenergy combined with carbon capture and storage, and options to increase ecosystem carbon uptake. The study found that CDR options like cover crops or seagrass restoration face low implementation hurdles but have small CO2 removal potentials, while options like woody‐biomass combustion or mixed‐feedstock biogas production have high CDR potentials but face large economic and institutional hurdles. The analysis aims to provide comprehensive information on CDR options for use in further research and as an effective decision support basis for a range of actors. Key Points: More context‐specific assessments of carbon dioxide removal (CDR) options are needed to guide national net‐zero decision makingEcosystem‐based CDR options with comparably low implementation hurdles in Germany show relatively small CO2 removal potentialsHigh CDR potential options in Germany face high institutional, technological and societal hurdles linked in many ways to geological storage [ABSTRACT FROM AUTHOR]

Large‐scale implementation of electrochemical CO2 conversion to value‐added products is currently hampered by high electrolyzer cell voltages, resulting in low energy efficiency and high operating costs. Cell voltages are typically well above 3 V and need to be significantly lowered whilst maintaining current densities greater than 200 mA cm−2 to enable energy‐efficient CO2 electroreduction. This can be addressed through modification of the resistive components of the device to reduce energy consumption and lower operating costs. Electrodes, electrolyte solutions, and the separator between compartments, provide the largest contributions to the overall cell voltage, therefore decreasing their resistance can lower the electricity input required to drive effective CO2 conversion. Here, by careful analysis and tuning of the various sources of voltage drops within the cell, an optimized diaphragm‐based CO2R device is presented, which is able to operate at an industrially relevant current density of 200 mA cm−2 with an |Ecell| as low as 2.89 V, amongst the lowest reported values to date. [ABSTRACT FROM AUTHOR]

Multiphysics modeling enables probing of conditions inside a CO2 electrolyzer that are difficult to measure, such as local concentrations and pH, as well as rapid testing of possible design changes. A one‐dimensional model for a zero‐gap membrane electrode assembly (MEA) CO2 electrolyzer was developed with the assumption that catalyst layers interact with the membrane ionomer such that the ionomer affects the underlying kinetics. The kinetics for bicarbonate reacting to form hydrogen are fit using a planar electrode model for silver with an ionomer coating. The MEA model results are validated against experimental studies for current density and product selectivity. Flooding of the cathode is modeled using saturation curves, and results show that blocked pores in the microporous layer play a significant role in limiting the mass transport at high potentials (>2.8 V). Sensitivity studies showed that CO Faradaic efficiency can be increased by decreasing catalyst layer thickness and porosity, and decreasing KHCO3 concentration. [ABSTRACT FROM AUTHOR]

Current estimates of carbon dioxide (CO2) evasion from Arctic lakes are highly uncertain because few studies integrate seasonal variability, specifically evasion during spring ice‐melt. We quantified annual CO2 evasion for 14 clear‐water Arctic lakes in Northern Sweden through mass balance (ice‐melt period) and high‐frequency loggers (open‐water period). On average, 80% (SD: ± 18) of annual CO2 evasion occurred within 10 d following ice‐melt. The contribution of the ice‐melt period to annual CO2 evasion was high compared to earlier studies of Arctic lakes (47% ± 32%). Across all lakes, the proportion of ice‐melt : annual CO2 evasion was negatively related to the dissolved organic carbon concentration and positively related to the mean depth of the lakes. The results emphasize the need for measurements of CO2 exchange at ice‐melt to accurately quantify CO2 evasion from Arctic lakes. [ABSTRACT FROM AUTHOR]

An unprecedented Et2Zn‐mediated gem‐dicarboxylation of C─C/C─H single bond of cyclopropanols with CO2 is disclosed, which provides a straightforward and efficient methodology for the synthesis of a variety of structurally diverse and useful malonic acids in moderate to excellent yields. The protocol features mild reaction conditions, excellent functional group compatibility, broad substrate scope, and facile derivatization of the products. DFT calculations confirm that the transition‐metal‐free transformation proceeds through a novel ring‐opening/α‐functionalization/ring‐closing/ring‐opening/β‐functionalization (ROFCOF) process, and 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) plays dual important roles in the transformation. [ABSTRACT FROM AUTHOR]

Crop models are often used to project future crop yield under climate and global change and typically show a broad range of outcomes. To understand differences in modeled responses, we analyzed modeled crop yield response types using impact response surfaces along four drivers of crop yield: carbon dioxide (C), temperature (T), water (W), and nitrogen (N). Crop yield response types help to understand differences in simulated responses per driver and their combinations rather than aggregated changes in yields as the result of simultaneous changes in various drivers. We find that models' sensitivities to the individual drivers are substantially different and often more different across models than across regions. There is some agreement across models with respect to the spatial patterns of response types but strong differences in the distribution of response types across models and their configurations suggests that models need to undergo further scrutiny. We suggest establishing standards in model evaluation based on emergent functionality not only against historical yield observations but also against dedicated experiments across different drivers to analyze emergent functional patterns of crop models. Plain Language Summary: Crop models are widely used to compute crop yields under future climate change. Yields are determined by many interacting processes. Simulated future crop yields often show a broad uncertainty range. We investigate the sensitivity of nine different crop models to individual model inputs (carbon dioxide, temperature, water, nitrogen) in a very large simulation data set and find that there are substantial differences. We conclude that crop model evaluation needs to include analyses of functional properties to avoid that very diverse model responses to drivers are not tracked if interacting processes cancel out in the historical evaluation period but not in future scenarios, leading to large differences between models. Key Points: Crop models show strong differences in input sensitivitiesStandardized modeling experiments reveal differences in emergent functional relationshipsNew standards in model evaluation are needed [ABSTRACT FROM AUTHOR]

Each year, the biological carbon pump (BCP) transports large quantities of carbon from the ocean surface to the interior. The efficiency of this transfer varies geographically, and is a key determinant of the atmosphere‐ocean carbon dioxide balance. Traditionally, the attention has been focused on explaining perceived geographical variations in this transfer efficiency (TE) in an attempt to understand it, an approach that has led to conflicting results. Here we combine observations and modeling to show that the spatial variability in TE can instead be explained by the seasonal variability in carbon flux attenuation. We also show that seasonality can explain the contrast between known global estimates of TE, due to differences in the date and duration of sampling. Our results suggest caution in the mechanistic interpretation of annual‐mean patterns in TE and demonstrates that seasonally and spatially resolved data sets and models might be required to generate accurate evaluations of the BCP. Plain Language Summary: Each year, marine phytoplankton convert carbon dioxide into millions of tonnes of organic carbon with a fraction of it reaching the deep ocean, where it can remain for hundreds of years. The efficiency of this surface‐to‐depth carbon transfer is therefore a key determinant of the atmosphere‐ocean carbon dioxide balance. However, the variability of this transfer efficiency (TE) and its underlying causes are poorly understood, to the extent that different studies report contradicting results. We show that the existence of seasonal variability in the attenuation of sinking carbon particles can explain the observed spatial variability in annual TE and reconcile with the literature. Our findings suggest caution in interpreting results from sparse but time‐varying data sets, highlighting that seasonal variability should be considered when studying the oceanic carbon cycle. Key Points: Spatial variability in carbon transfer efficiency (TE) can be generated solely by the seasonality of flux attenuation informed by observationsSeasonality in flux attenuation can reconcile contrasting TE maps reported in the literatureResolving and understanding seasonality are key for an accurate evaluation of the biological carbon pump under climate change [ABSTRACT FROM AUTHOR]

It is found that aralkylamines solidified even in water by absorption of aerial CO2. Despite being amphiphilic, the aralkylamines absorbed CO2 and self‐assembled against the amphiphilicity to form a reverse lipid bilayer structure and solidified. Once the solid‐liquid separation of aerial CO2‐captured amines in water is achieved, it becomes possible to select the optimum conditions for both absorption and desorption. [ABSTRACT FROM AUTHOR]

In order to deal with the global energy crisis and environmental problems, reducing carbon dioxide through artificial photosynthesis has become a hot topic. Lead halide perovskite is attracted people's attention because of its excellent photoelectric properties, but the toxicity and long‐term instability prompt people to search for new photocatalysts. Herein, a series of <111> inorganic double perovskites Cs4Mn1‐xCuxSb2Cl12 microcrystals (x = 0, 0.1, 0.2, 0.3, 0.4, and 0.5) are synthesized and characterized. Among them, Cs4Mn0.7Cu0.3Sb2Cl12 microcrystals have the best photocatalytic performance, and the yields of CO and CH4 are 503.86 and 68.35 µmol g−1, respectively, after 3 h irradiation, which are the highest among pure phase perovskites reported so far. In addition, in situ Fourier transform infrared (FT‐IR) spectroscopy and electron spin resonance (ESR) spectroscopy are used to explore the mechanism of the photocatalytic reaction. The results highlight the potential of this class of materials for photocatalytic reduction reactions. [ABSTRACT FROM AUTHOR]

Electrochemical C–C and C–N coupling reactions with the conversion of abundant and inexpensive small molecules, such as CO2 and nitrogen‐containing species, are considered a promising route for increasing the value of CO2 reduction products. The development of high‐performance catalysts is the key to the both electrocatalytic reactions. In this review, we present a systematic summary of the reaction systems for electrocatalytic CO2 reduction, along with the coupling mechanisms of C–C and C–N bonds over outstanding electrocatalytic materials recently developed. The key intermediate species and reaction pathways related to the coupling as well as the catalyst‐structure relationship will be also discussed, aiming to provide insights and guidance for designing efficient CO2 reduction systems. [ABSTRACT FROM AUTHOR]

The Ansanto Valley's Mefite, one of the Earth's largest non‐volcanic CO2 gas emissions, is distinguished by its cold natural carbon dioxide springs. These emissions originate from the intricate tectonics and geodynamics of the southern Apennines in Italy. Known for over two millennia for its lethal concentration of CO2 and other harmful gases, the Mefite has a reputation for being toxic and dangerous. Despite its historical significance and unique geological features, there is a lack of information on the microbial diversity associated with the Mefite's gas emissions. This study presents an integrated exploration of the microbial diversity in the mud soil, using high‐throughput sequencing of 16S rRNA (Prokaryotes) and ITS2 (Fungi), alongside a geochemical site characterisation. Our findings reveal that the Mefite's unique environment imposes a significant bottleneck on microbial diversity, favouring a select few microbial groups such as Actinobacteria and Firmicutes for Prokaryotes, and Basidiomycota for Fungi. [ABSTRACT FROM AUTHOR]