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Motivated by the multiferroic effects and quantum magnetization plateaus in the skew chain antiferromagnets T 2 V 2 O 7 (T = Ni, Co), we have conducted a detailed density function theoretical study on Co 2 V 2 O 7. The results show that the nearest-neighbor interchain interaction (J 3 / k B = − 35.57 K) is not much greater than the intrachain interactions (J 1 / k B = − 19.54 K and J 2 / k B = 27.55 K), showing the absence of interchain dimerization of the Co ions. This indicates that the "dimer+monomer" model used for Ni 2 V 2 O 7 [Cao et al., Phys. Rev. B 106, 184409 (2022)] is no longer applicable to Co 2 V 2 O 7. Finally, the exact diagonalization of spin Hamiltonian, including anisotropic exchanges, produces the experimentally observed 1/2 and 3/4 magnetization plateaus. [ABSTRACT FROM AUTHOR]

Motivated by the multiferroic effects and quantum magnetization plateaus in the skew chain antiferromagnets T 2 V 2 O 7 (T = Ni, Co), we have conducted a detailed density function theoretical study on Co 2 V 2 O 7. The results show that the nearest-neighbor interchain interaction (J 3 / k B = − 35.57 K) is not much greater than the intrachain interactions (J 1 / k B = − 19.54 K and J 2 / k B = 27.55 K), showing the absence of interchain dimerization of the Co ions. This indicates that the "dimer+monomer" model used for Ni 2 V 2 O 7 [Cao et al., Phys. Rev. B 106, 184409 (2022)] is no longer applicable to Co 2 V 2 O 7. Finally, the exact diagonalization of spin Hamiltonian, including anisotropic exchanges, produces the experimentally observed 1/2 and 3/4 magnetization plateaus. [ABSTRACT FROM AUTHOR]

Purpose: To measure the surface temperature distribution after using a CO2 laser to heat titanium dental implants via different power settings, application intervals, and irradiation times. Materials and Methods: A total of 10 tissue-level titanium implants (Screw-Line Promote Plus, Camlog; 4.3 × 11 mm) were placed (EpoFix, Struers) and irradiated with a CO2 laser (Denta 2, Lutronic) with a wavelength of 10.6 µm at power levels of 4 watts (Group 1), 6 watts (Group 2), 8 watts (Group 3), and 10 watts (Group 4). A continuous beam mode (setting I) and noncontinuous beam modes with 5-second (setting II) and 10-second (setting III) pause intervals were used. For each setting, a total irradiation time of 50 seconds was used and repeated 10 times. The temperature was measured using external thermocouple (Testo) in contact with the implant surface at the implant shoulder, middle, and apex. A linear regression model was used to analyze the data (P = .05). Results: Setting I demonstrated the most rapid increase in implant surface temperature in all three test sites as well as the greatest total temperature at 50 seconds of irradiation time. The greater the pause interval (settings II and III) during the 50 seconds of irradiation, the lower the rate of temperature increase as well as the total temperature in all three test sites and with all power levels. The average temperature difference between the apex and shoulder site was significant for setting III for all groups, but not for any groups in settings I and II. Conclusions: Heating the internal aspect of an implant with a CO2 laser produces different temperature distribution profiles depending on the laser power level and the application interval. Laser-beam irradiation leads to a temperature gradient, which is greatest at the implant apex and smallest at the implant shoulder. [ABSTRACT FROM AUTHOR]

Localization procedures are an important tool for analysis of complex systems in quantum chemistry, since canonical molecular orbitals are delocalized and can, therefore, be difficult to align with chemical intuition and obscure information at the local level of the system. This especially applies to calculations obeying periodic boundary conditions. The most commonly used approach to localization is Foster–Boys Wannier functions, which use a unitary transformation to jointly minimize the second moment of the orbitals. This procedure has proven to be robust and fast but has a side effect of often mixing σ - and π -type orbitals. σ / π -separation is achieved by the Pipek–Mezey Wannier function (PMWF) approach [Lehtola and Jónsson, J. Chem. Theory Comput. 10, 642 (2014) and Jónsson et al., J. Chem. Theory Comput. 13, 460 (2017)], which defines the spread functional in terms of partial charges instead. We have implemented a PMWF algorithm in the CP2K software package using the Cardoso–Souloumiac algorithm to enable their application to real-time time-dependent density functional theory. The method is demonstrated on stacked CO 2 molecules, linear acetylenic carbon, boron and nitrogen co-doped graphene, and nitrogen-vacancy doped diamond. Finally, we discuss its computational scaling and recent efforts to improve it with fragment approaches. [ABSTRACT FROM AUTHOR]

Purpose: To assess (1) whether and how a higher maximal lactate steady state (MLSS) at higher cycling cadence (RPM) comes along with higher absolute and/or fractional carbohydrate combustion (CHOMLSS), respectively, and (2) whether there is an interrelation between potential RPM-dependent MLSS effects and the maximally achievable RPM (RPMMAX). Methods: Twelve healthy males performed incremental load tests to determine peak power, peak oxygen uptake, and 30-minute MLSS tests at 50 and 100 per minute, respectively, to assess RPM-dependent MLSS, corresponding power output, CHOMLSS responses, and 6-second sprints to measure RPMMAX. Results: Peak power, peak carbon dioxide production, and power output at MLSS were lower (P =.000, ω2 = 0.922; P =.044, ω2 > 0.275; and P =.016, ω2 = 0.373) at 100 per minute than at 50 per minute. With 6.0 (1.5) versus 3.8 (1.2) mmol·L−1, MLSS was higher (P =.000, ω2 = 0.771) at 100 per minute than at 50 per minute. No corresponding RPM-dependent differences were found in oxygen uptake at MLSS, carbon dioxide production at MLSS, respiratory exchange ratio at MLSS, CHOMLSS, or fraction of oxygen uptake used for CHO at MLSS, respectively. There was no correlation between the RPM-dependent difference in MLSS and RPMMAX. Conclusions: The present study extends the previous finding of a consistently higher MLSS at higher RPM by indicating (1) that at fully established MLSS conditions, respiration and CHOMLSS management do not differ significantly between 100 per minute and 50 per minute, and (2) that linear correlation models did not identify linear interdependencies between RPM-dependent MLSS conditions and RPMMAX. [ABSTRACT FROM AUTHOR]

In this work, the effect of the range of dispersive interactions in determining the three-phase coexistence line of the CO2 and CH4 hydrates has been studied. In particular, the temperature (T3) at which solid hydrate, water, and liquid CO2/gas CH4 coexist has been determined through molecular dynamics simulations using different cutoff values (from 0.9 to 1.6 nm) for dispersive interactions. The T3 of both hydrates has been determined using the direct coexistence simulation technique. Following this method, the three phases in equilibrium are put together in the same simulation box, the pressure is fixed, and simulations are performed at different temperatures T. If the hydrate melts, then T > T3. Conversely, if the hydrate grows, then T < T3. The effect of the cutoff distance on the dissociation temperature has been analyzed at three different pressures for CO2 hydrate: 100, 400, and 1000 bar. Then, we have changed the guest and studied the effect of the cutoff distance on the dissociation temperature of the CH4 hydrate at 400 bar. Moreover, the effect of long-range corrections for dispersive interactions has been analyzed by running simulations with homo- and inhomogeneous corrections and a cutoff value of 0.9 nm. The results obtained in this work highlight that the cutoff distance for the dispersive interactions affects the stability conditions of these hydrates. This effect is enhanced when the pressure is decreased, displacing the T3 about 2–4 K depending on the system and the pressure. [ABSTRACT FROM AUTHOR]

In this work, the effects of finite size on the determination of the three-phase coexistence temperature (T3) of the carbon dioxide (CO2) hydrate have been studied by molecular dynamic simulations and using the direct coexistence technique. According to this technique, the three phases involved (hydrate–aqueous solution–liquid CO2) are placed together in the same simulation box. By varying the number of molecules of each phase, it is possible to analyze the effect of simulation size and stoichiometry on the T3 determination. In this work, we have determined the T3 value at 8 different pressures (from 100 to 6000 bar) and using 6 different simulation boxes with different numbers of molecules and sizes. In two of these configurations, the ratio of the number of water and CO2 molecules in the aqueous solution and the liquid CO2 phase is the same as in the hydrate (stoichiometric configuration). In both stoichiometric configurations, the formation of a liquid drop of CO2 in the aqueous phase is observed. This drop, which has a cylindrical geometry, increases the amount of CO2 available in the aqueous solution and can in some cases lead to the crystallization of the hydrate at temperatures above T3, overestimating the T3 value obtained from direct coexistence simulations. The simulation results obtained for the CO2 hydrate confirm the sensitivity of T3 depending on the size and composition of the system, explaining the discrepancies observed in the original work by Míguez et al. [J. Chem Phys. 142, 124505 (2015)]. Non-stoichiometric configurations with larger unit cells show a convergence of T3 values, suggesting that finite-size effects for these system sizes, regardless of drop formation, can be safely neglected. The results obtained in this work highlight that the choice of a correct initial configuration is essential to accurately estimate the three-phase coexistence temperature of hydrates by direct coexistence simulations. [ABSTRACT FROM AUTHOR]

Climate changes significantly impact greenhouse gas emissions from wetland soil. Specifically, wetland soil may be exposed to oxygen (O2) during droughts, or to sulfate (SO42-) as a result of sea level rise. How these stressors - separately and together - impact microbial food webs driving carbon cycling in the wetlands is still not understood. To investigate this, we integrated geochemical analysis, proteogenomics, and stoichiometric modeling to characterize the impact of elevated SO42- and O2 levels on microbial methane (CH4) and carbon dioxide (CO2) emissions. The results uncovered the adaptive responses of this community to changes in SO42- and O2 availability and identified altered microbial guilds and metabolic processes driving CH4 and CO2 emissions. Elevated SO42- reduced CH4 emissions, with hydrogenotrophic methanogenesis more suppressed than acetoclastic. Elevated O2 shifted the greenhouse gas emissions from CH4 to CO2. The metabolic effects of combined SO42- and O2 exposures on CH4 and CO2 emissions were similar to those of O2 exposure alone. The reduction in CH4 emission by increased SO42- and O2 was much greater than the concomitant increase in CO2 emission. Thus, greater SO42- and O2 exposure in wetlands is expected to reduce the aggregate warming effect of CH4 and CO2. Metaproteomics and stoichiometric modeling revealed a unique subnetwork involving carbon metabolism that converts lactate and SO42- to produce acetate, H2S, and CO2 when SO42- is elevated under oxic conditions. This study provides greater quantitative resolution of key metabolic processes necessary for the prediction of CH4 and CO2 emissions from wetlands under future climate scenarios.

Cities represent a significant and growing portion of global carbon dioxide (CO2) emissions. Quantifying urban emissions and trends over time is needed to evaluate the efficacy of policy targeting emission reductions as well as to understand more fundamental questions about the urban biosphere. A number of approaches have been proposed to measure, report, and verify (MRV) changes in urban CO2 emissions. Here we show that a modest capital cost, spatially dense network of sensors, the Berkeley Environmental Air Quality and CO2 Network (BEACO2N), in combination with Bayesian inversions, result in a synthesis of measured CO2 concentrations and meteorology to yield an improved estimate of CO2 emissions and provide a cost-effective and accurate assessment of CO2 emissions trends over time. We describe nearly 5 years of continuous CO2 observations (2018-2022) in a midsized urban region (the San Francisco Bay Area). These observed concentrations constrain a Bayesian inversion that indicates the interannual trend in urban CO2 emissions in the region has been a modest decrease at a rate of 1.8 ± 0.3%/year. We interpret this decrease as primarily due to passenger vehicle electrification, reducing on-road emissions at a rate of 2.6 ± 0.7%/year.

The rare earth alloy Y 2 Co 17 − x Ni x was prepared by a low-cost co-precipitation reduction-diffusion process, and its crystal structure, static magnetic properties, and microscopic morphology were systematically characterized. The effects of Ni doping with different contents on the electromagnetic parameters and wave absorption properties of Y 2 Co 17 − x Ni x /polyurethane(PU) compounds were researched in the frequency range of 0.1–18 GHz. The results show that the static magnetic properties and wave absorption properties change significantly with Ni doping, and the maximum reflection loss of Y 2 Co 14 Ni 3 /PU reaches − 89.7 dB at 2.9 mm thickness, and the maximum reflection loss peaks of Y 2 Co 17 /PU and Y 2 Co 16 Ni 1 /PU are at 1.316 and 1.515 GHz, which is at the center frequency of the L-band. With Ni doping, the effective absorption bandwidth of the compounds at a frequency above 3 GHz is greatly increased. The physical factor in the bandwidth calculation was modified, and the effective absorption bandwidth of the material was calculated theoretically, and the error was less than 5 % compared with the experimental value. [ABSTRACT FROM AUTHOR]

BackgroundInfants with hypoxic-ischemic encephalopathy are often treated with therapeutic hypothermia and high-frequency ventilation. Fluctuations in PaCO2 during therapeutic hypothermia are associated with poor neurodevelopmental outcomes. Transcutaneous CO2 monitors offer a noninvasive estimate of PaCO2 represented by transcutaneously measured partial pressure of carbon dioxide (PtcCO2 ). We aimed to assess the precision between PtcCO2 and PaCO2 values in neonates undergoing therapeutic hypothermia.MethodsThis was a retrospective chart review of 10 neonates who underwent therapeutic hypothermia requiring respiratory support over 2 y. A range of 2-27 simultaneous PtcCO2 and PaCO2 pairs of measurements per neonate were analyzed via linear mixed models and a Bland-Altman plot for multiple observations per neonate.ResultsA linear mixed-effect model demonstrated that PtcCO2 and PaCO2 (controlling for sex) were similar. The 95% CI of the mean difference ranged from -2.3 to 5.7 mm Hg (P = .41). However, precision was poor as the PtcCO2 ranged from > 18 mm Hg to < 13 mm Hg than PaCO2 values for 95% of observations.ConclusionsThe neonates' PtcCO2 was as much as 18 mm Hg higher to 13 mm Hg lower than the PaCO2 95% of the time. Transcutaneous CO2 monitoring may not be a good trending tool, nor is it appropriate for estimating PaCO2 in patients undergoing therapeutic hypothermia.

Heat stress results in significant economic losses to the poultry industry. Genetics plays an important role in chickens adapting to the warm environment. Physiological parameters such as hematochemical parameters change in response to heat stress in chickens. To explore the genetics of heat stress resilience in chickens, a genome-wide association study (GWAS) was conducted using Hy-Line Brown layer chicks subjected to either high ambient temperature or combined high temperature and Newcastle disease virus infection. Hematochemical parameters were measured during three treatment phases: acute heat stress, chronic heat stress, and chronic heat stress combined with NDV infection. Significant changes in blood parameters were recorded for 11 parameters (sodium (Na+, potassium (K+), ionized calcium (iCa2+), glucose (Glu), pH, carbon dioxide partial pressure (PCO2), oxygen partial pressure (PO2), total carbon dioxide (TCO2), bicarbonate (HCO3), base excess (BE), and oxygen saturation (sO2)) across the three treatments. The GWAS revealed 39 significant SNPs (p < 0.05) for seven parameters, located on Gallus gallus chromosomes (GGA) 1, 3, 4, 6, 11, and 12. The significant genomic regions were further investigated to examine if the genes within the regions were associated with the corresponding traits under heat stress. A candidate gene list including genes in the identified genomic regions that were also differentially expressed in chicken tissues under heat stress was generated. Understanding the correlation between genetic variants and resilience to heat stress is an important step towards improving heat tolerance in poultry.

An animals preference for many chemosensory cues remains constant despite dramatic changes in the animals internal state. The mechanisms that maintain chemosensory preference across different physiological contexts remain poorly understood. We previously showed that distinct patterns of neural activity and motor output are evoked by carbon dioxide (CO2) in starved adults vs dauers of Caenorhabditis elegans, despite the two life stages displaying the same preference (attraction) for CO2. However, how the distinct CO2-evoked neural dynamics and motor patterns contribute to CO2 attraction at the two life stages remained unclear. Here, using a CO2 chemotaxis assay, we show that different interneurons are employed to drive CO2 attraction at the two life stages. We also investigate the molecular mechanisms that mediate CO2 attraction in dauers vs adults. We show that insulin signaling promotes CO2 attraction in dauers but not starved adults and that different combinations of neurotransmitters and neuropeptides are used for CO2 attraction at the two life stages. Our findings provide new insight into the distinct molecular and cellular mechanisms used by C. elegans at two different life stages to generate attractive behavioral responses to CO2.

Plants with the C4 photosynthesis pathway typically respond to climate change differently from more common C3-type plants, due to their distinct anatomical and biochemical characteristics. These different responses are expected to drive changes in global C4 and C3 vegetation distributions. However, current C4 vegetation distribution models may not predict this response as they do not capture multiple interacting factors and often lack observational constraints. Here, we used global observations of plant photosynthetic pathways, satellite remote sensing, and photosynthetic optimality theory to produce an observation-constrained global map of C4 vegetation. We find that global C4 vegetation coverage decreased from 17.7% to 17.1% of the land surface during 2001 to 2019. This was the net result of a reduction in C4 natural grass cover due to elevated CO2 favoring C3-type photosynthesis, and an increase in C4 crop cover, mainly from corn (maize) expansion. Using an emergent constraint approach, we estimated that C4 vegetation contributed 19.5% of global photosynthetic carbon assimilation, a value within the range of previous estimates (18-23%) but higher than the ensemble mean of dynamic global vegetation models (14 ± 13%; mean ± one standard deviation). Our study sheds insight on the critical and underappreciated role of C4 plants in the contemporary global carbon cycle.

The resident human skin microbiome is responsible for the production of most of the human scents that are attractive to mosquitoes. Hence, engineering the human skin microbiome to synthesize less of mosquito attractants or produce repellents could potentially reduce bites and prevent the transmission of deadly mosquito-borne pathogens. In order to further characterize the human skin volatilome, we quantified the major volatiles of 39 strains of skin commensals (Staphylococci and Corynebacterium). Importantly, to validate the behavioral activity of these volatiles, we first assessed landing behavior triggered by human skin volatiles. We demonstrated that landing behavior is gated by the presence of carbon dioxide and L-(+)-lactic acid. This is similar to the combinatorial coding triggering mosquito short range attraction. Repellency behavior to selected skin volatiles and terpenes was tested in the presence of carbon dioxide and L-(+)-lactic acid. In a 2-choice landing behavior context, the skin volatiles 2- and 3-methyl butyric acids reduced mosquito landing by 62.0-81.6% and 87.1-99.6%, respectively. Similarly, the terpene geraniol was capable of reducing mosquito landing behavior by 74.9%. We also tested the potential repellency effects of terpenes in mosquitoes at short-range using a 4-port olfactometer. In these assays, geraniol reduced mosquito attraction (69-78%) to a mixture of key human kairomones carbon dioxide, L-(+)-lactic acid, and ammonia. These findings demonstrate that carbon dioxide and L-(+)-lactic acid change the valence of other skin volatiles towards mosquito landing behavior. Moreover, this study offers candidate odorants to be targeted in a novel strategy to reduce attractants or produce repellents by the human skin microbiota that may curtail mosquito bites, and subsequent mosquito-borne disease.

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 CO2 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, CO2 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.

Two-step redox thermochemical cycles, capable of directly converting CO 2 and H 2 O respectively into CO and H 2 , offer a promising synthesis route towards green carbon-neutral fuels. The performance of such two-step cycles depends highly on the thermodynamic properties of splitting materials, particularly the solid-state enthalpy ( Δ h solid) and entropy (Δ s solid) changes during the reduction process. Here, we report an investigation into the roles of the Δ h solid and Δ s solid. We shall show that a high Δ s solid relaxes both reduction temperature and oxygen pressure, but increases oxidant consumption. Conversely, an increase in Δ h solid enhances reduction resistance while promotes oxidation reactions. There are therefore no perfect materials, and a trade-off is needed for an optimal solution. We also defined a thermodynamic region based on Δ h solid and Δ s solid and typical operating conditions, and showed that higher values of both Δ h solid and Δ s solid provided a larger reaction space. While lower Δ h solid and negative Δ s solid may be more suitable for isothermal cycles. Our analyses also suggest future efforts in searching for splitting materials with a high Δ s solid within an appropriate range of Δ h solid (280–460 kJ/mol). [Display omitted] • Trade-off caused by solid state enthalpy and entropy is a key issue. • High solid-state enthalpy and entropy are more suitable for temperature-swing cycle. • A thermodynamic region under typical operating conditions is defined. • Solid-state entropy of different candidate materials is discussed. [ABSTRACT FROM AUTHOR]

Methane pyrolysis is emerging as an attractive clean hydrogen production method. As its commercialization proceeds, the pyrolysis of natural gas (NG) becomes pertinent. In this work, the decomposition of pure methane and a realistic NG mixture are compared experimentally and numerically. Methane and NG pyrolysis are performed between 600 and 1200 °C over a fluidized bed of carbon particles heated by microwaves. Experimentally, no conclusive difference is observed in methane conversion between methane and NG pyrolysis. Numerically, the methane conversion rate is 8.5% higher for NG at 950 °C. The difference diminishes past 950 °C, becoming 0 past 1050 °C. The simulations showed that the enhanced methane decomposition in NG pyrolysis is due to an attack on methane by radicals generated during ethane and propane decomposition. The CO 2 in our NG mixture decomposes into CO. This work validates the longstanding use of methane pyrolysis as a surrogate for NG pyrolysis. • Experimentally, no conclusive difference between NG and pure CH 4 pyrolysis. • Numerically, NG pyrolysis had at most 8.5% higher methane conversion. • Radicals from ethane decomposition attacked methane and increased methane conversion. • Inlet C 2 H 6 > 10 vol% increased the outlet CH 4 rather than aiding its decomposition. • CO 2 in the NG mixture decomposed into CO, implying non-zero GHG emissions. [ABSTRACT FROM AUTHOR]

AlH 3 is a high-capacity hydrogen storage material but is prone to explosion. Thermodynamic and structural properties of AlH 3 -nanoparticles at different CO 2 inerting systems from ignition to combustion are studied using ReaxFF-MD method. The influence of CO 2 on AlH 3 -nanoparticles ignition and combustion is investigated by comparing the changes of surface O adsorption rates, particle charge, temperature rise rates and so on. Results indicate that an increase in CO 2 is crucial for suppressing AlH 3 -nanoparticles ignition and combustion by impeding the formation of an Al-rich environment. In contrast to three stages of AlH 3 -nanoparticles combustion in pure O 2 system: surface combustion, slow temperature rise, and self-sustaining combustion, the process of CO 2 inerting system is different, with third stage is slow temperature rise at a constant rate. When CO 2 concentration reaches to 90%, the dehydrogenation rate reduces by 70.0%, the temperature rise rate decreases by 78.6%, and the ignition delay time reaches 45 ps. [Display omitted] • The mechanism of CO 2 inhibition on ignition and combustion of AHNP is clarified. • The influence of CO 2 on AHNP dehydrogenation is also elucidated. • Revealing mechanisms at the atomic scale. [ABSTRACT FROM AUTHOR]

Given that SOF materials have both inorganic and organic properties and are easy to prepare and structurally designable, this paper carries out the microbehavioral analysis and membrane design of SOF-8, SOF-9, and SOF-10 membranes for the hydrogen purification process of RMFCs. Since three materials have complementary performance characteristics for hydrogen purification, this paper focuses on the gas separation behavior of these three composite membranes using molecular dynamics simulations. Results showed that the SOF-9a+10a composite membranes could 100% block CO 2 and CO, and displayed an excellent H 2 permeability of 6.118 × 105 GPU during H 2 /CO 2 separation, which exceeded the industry standard by nearly 105 times. Additionally, the SOF-9a+8 and SOF-10a+8 composite membranes improved gas selectivity and maintained high H 2 permeability. Moreover, microdiffusion analyses revealed that the small pore sizes and irregular-shaped pore channels effectively hindered CO 2 and CO transport. Microscopic analysis shows the potential of SOF composite membranes for gas separation. [Display omitted] • SOF composite membranes can effectively improve gas selectivity. • Small pore sizes and irregular pore channels can effectively block CO 2 transport. • SOF-9a+10 can 100% intercept CO 2 and CO. • The interaction between gas and membrane affects the gas separation performance. [ABSTRACT FROM AUTHOR]

The research has examined the effects of CO 2 dilution on ignition characteristics in H 2 /air mixtures. An ignition kernel was initiated by a laser-induced plasma in H 2 /air/CO 2 mixtures with a bulk velocity of 6.5 m/s. An infrared camera was used to measure radiation intensity emitted from H 2 O and ignition probabilities. A high-speed schlieren image system was utilized to measure ignition kernel areas and ignition time. High-speed chemiluminescence was performed to examine OH* intensities. Numerical simulations were conducted using GRI 3.0 mechanisms to calculate reaction rates and laminar flame speeds. The ignition probability is highest for the undiluted mixtures and decreases with increasing the CO 2 dilution fraction at constant adiabatic temperatures. A prolonged ignition time is observed at elevated CO 2 dilution concentrations. Increasing the CO 2 mole fraction decreases the ignition kernel growth, the integrated OH* intensity, and the integrated radiation intensity for each adiabatic temperature. CO 2 reacts with H radicals and decreases the production of OH*, OH, and H 2 O. The CO 2 dilution in the H 2 /air flames significantly contributes to the reduced reaction rate and flame speed, resulting in the low ignition probability. The high ignition probability is found at the large integrated OH* intensity in all cases. The ignition probability is high at the large integrated radiation intensity under the constant adiabatic flame temperatures. The OH* intensity is a critical parameter to estimate the ignition probability in the diluted lean hydrogen flames. • The effects of CO 2 dilution on the ignition process have been studied in lean premixed H 2 /Air flames. • The ignition probability decreases with increasing the CO 2 dilution fraction. • An increase in the CO 2 dilution fraction in the mixtures reduces OH* intensity and radiation intensity emitted from H 2 O. • The presence of CO 2 in the mixtures decreases reaction rates and flame speed. [ABSTRACT FROM AUTHOR]

Defect engineering has been widely applied in the field of photocatalysis, and defects can be used to modify the surface structure and photoelectric properties of catalysts so as to achieve the purpose of regulating the activity and stability of catalysts. However, design of a highly efficient photocatalyst with abundant defects remains a challenging task in current research. Therefore, in this study, graphitic carbon nitride (g-C 3 N 4) with abundant three-coordinated nitrogen (N 3C) vacancies and pore structures was obtained using a facile hydrothermal method with the assistance of glycerol. Under visible light (λ > 420 nm) irradiation, the 50CN (volume ratio of glycerol/water is 50/10) catalyst exhibits a superior CO release rate (4.18 μmol g−1 h−1), which is 12.06 times higher than the reference GCN (0.32 μmol g−1 h−1), and the corresponding apparent quantum yields (AQY) of 50CN is 0.24 %, which is significantly higher than that of GCN (0.045 %). Successful introduction of N 3C vacancies is conducive to broaden light response range of the catalyst, enhancing the separation and migration efficiency of photogenerated charges, and providing more adsorption active sites to promote the adsorption and activation of CO 2 molecules, thus effectively boosting photocatalytic CO 2 reduction activity. In addition, the N 3C vacancies can effectively lower the CO 2 activation energy barrier and reduce the energy consumption required for the reaction. This work offers valuable new insights into defect engineering in g-C 3 N 4 for the development of high-performance photocatalysts for CO 2 reduction. [ABSTRACT FROM AUTHOR]

We integrated a pair of donor–acceptor photothermal units, a Lewis acidic site, and a nucleophilic catalytic site into a multi-component metal–organic framework, resulting in an efficient photothermal catalytic system for the conversion of CO2 to cyclic carbonates. [ABSTRACT FROM AUTHOR]

• CaCl 2 is an additive suitable for pyrometallurgical recovery of spent LIBs. • CaCl 2 has good chlorination ability and slag optimization ability. • SiO 2 and CO 2 in the system contribute to the increase in HCl yield. The difficulty of separating Li during pyrometallurgical smelting of spent lithium-ion batteries (LIBs) has limited the development of pyrometallurgical processes. Chlorination enables the conversion of Li from spent LIBs to the gas phase during the smelting process. In this paper, the effects of four solid chlorinating agents (KCl, NaCl, CaCl 2 and MgCl 2) on Li volatilization and metal (Co, Cu, Ni and Fe) recovery were investigated. The four solid chlorinating agents were systematically compared in terms of the direct chlorination capacities, indirect chlorination capacities, alloy physical losses and chemical losses in the slag. CaCl 2 was better suited for use as a solid chlorinating agent to promote Li volatilization due to its excellent results in these indexes. The temperature required for the release of HCl from MgCl 2 , facilitated by CO 2 and SiO 2 , was lower than 500 °C. The prematurely released HCl failed to participate in the chlorination reaction. This resulted in approximately 12 % less Li volatilization when MgCl 2 was used as a chlorinating agent compared to when CaCl 2 was used. In addition, the use of KCl as a chlorinating agent decreased the chemical dissolution loss of alloys in the slag. The performance of NaCl was mediocre. Finally, based on evaluations of the four indexes, recommendations for the selection and optimization of solid chlorinating agents were provided. [ABSTRACT FROM AUTHOR]

[Display omitted] The Sudokwon landfill (SL) in the Seoul metropolitan area, South Korea, is among the world's largest landfills, striving to curtail landfill gas (LFG) emissions and achieve carbon neutrality by 2050. Since 2005, the SL Management Corporation (SLC) has measured LFG emissions (i.e., methane (CH 4) and carbon dioxide (CO 2)) using a dynamic flux chamber proposed by the US EPA. However, uncertainty prevails in validating the reduction of LFG emissions due to the limited spatiotemporal data coverage. In 2020, an eddy covariance (EC) system was installed to enhance measurements, revealing highly fluctuating LFG emissions driven by waste layer LFG production, LFG collection, and atmospheric pressure changes. During the study period, the annual CH 4 emission increased slightly from 465.0 ± 4.2 to 485.5 ± 6.4 g C m−2, while that of CO 2 decreased by 2/3 (from 408.7 ± 16.5 to 270.6 ± 18.8 g C m−2), primarily due to the doubled CO 2 uptake by the vegetated topsoil. Our first long-term (March 2020 to February 2022) quasi-continuous monitoring using EC (with a gap-filling and partitioning technique based on Random Forest) emphasizes the difficulty of temporal upscaling of discontinuously observed surface emissions to quantify the LFG inventory and the need for continuous observations or suitable proxies (e.g., atmospheric CH 4 concentration). [ABSTRACT FROM AUTHOR]

By embedding Na ions into graphitic carbon nitride, the directional migration of photo-generated electrons towards Na sites is achieved, thereby creating additional reaction sites. Moreover, the electron-rich Na sites enhance the adsorption and activation of CO 2. Consequently, the photocatalytic performance is improved to some extent. [Display omitted] The depressed directional separation of photogenerated carriers and weak CO 2 adsorption/activation activity are the main factors hampering the development of artificial photosynthesis. Herein, Na ions are embedded in graphitic carbon nitride (g-C 3 N 4) to achieve directional migration of the photogenerated electrons to Na sites, while the electron-rich Na sites enhance CO 2 adsorption and activation. Na/g-C 3 N 4 (NaCN) shows improved photocatalytic reduction activity of CO 2 to CO and CH 4 , and under simulated sunlight irradiation, the CO yield of NaCN synthesized by embedding Na at 550°C (NaCN-550) is 371.2 μmol g−1 h−1, which is 58.9 times more than that of the monomer g-C 3 N 4. By means of theoretical calculations and experiments including in situ fourier transform infrared spectroscopy, the mechanism is investigated. This strategy which improves carrier separation and reduces the energy barrier at the same time is important to the development of artificial photosynthesis. [ABSTRACT FROM AUTHOR]

Two new neodymium-based metal–organic frameworks, JMS-10 and JMS-11, were synthesised using a 2,2′-bipypridine-5,5′-dicarboxylic acid (bpdc) linker. Both MOFs were solvothermally synthesised in DMF under different conditions. JMS-10 was synthesised at 120 °C while JMS-11 was synthesised at 100 °C in the presence of a modulator. Both the MOFs possessed very similar crystallographic parameters but were found to be structurally diverse. Their structures were built by secondary building units (SBUs) made up of carboxylates binding in sets of four and two to the straight rod, thus forming two types of alternating nodes that are 6- and 4-connected. Both JMS-10 and JMS-11 were functionalized using the ruthenium p-cymene complex. The functionalized MOFs were applied in the photocatalytic reduction of carbon dioxide to syngas where they produced both hydrogen and carbon monoxide (CO : H2) in the ratio of 1 : 2. The amount of CO to H2 produced varied depending on the additives used in the reaction medium, highlighting the importance of water, triethanolamine and acetonitrile in tuning the syngas ratio for different industrial applications. [ABSTRACT FROM AUTHOR]

ABSTRACT Sulfur dioxide is serious ultimatum to human health as well as environment, while carbon dioxide is viewed as one of the primary drivers of the worldwide temperature alteration. Therefore, capturing of these gases is a dynamic research subject attracting much consideration from scientists. Herein, we report synthesis of a series of Co‐ZIF and bimetallic M‐Co‐ZIF adsorbents and application for room temperature adsorption of SO2 and CO2. In this work, the breakthrough curves for the adsorption of sulfur dioxide and carbon dioxide on Co‐ZIF and M‐Co‐ZIF were obtained experimentally and theoretically using a laboratory‐scale fixed bed column at room temperature. In this work, the adsorption capacities and breakthrough points for modified bimetallic M‐Co‐ZIF were found to be relatively higher than parent Co‐ZIF. Notably, a high SO2 uptake capacity of 7.1 mmol/g for Zr‐Co‐ZIF and high CO2 uptake capacity of 69.9 mmol/g for Ni‐Co‐ZIF were achieved. The parent cobalt and bimetallic ZIF materials were characterized by XRD, FTIR, SEM, and nitrogen physisorption. The XRD results confirm the formation of pure phase highly crystalline ZIF materials while BET analysis suggests high surface area of prepared adsorbents. Finally, the results of dynamic adsorption combined with characterization show great potential for preparation of bimetallic ZIF adsorbents for effective SO2 and CO2 adsorption. [ABSTRACT FROM AUTHOR]

This study introduces a novel method for hydrogen fuel generation using ultrasound technology through the disassociation of water into hydrogen and oxygen. The proposed experimental setup comprises several key components: a power supply, an ultrasonic generator, two transducers, a reactor vessel, two vapor traps, a condenser, a valve, a hydrogen storage, a humidity sensor and a hydrogen measurement sensor. The system operates at a power of 100 W and a frequency of 40 kHz, and the reactor vessel contains 2L of solution. The study results show a variability in hydrogen production rates under different experimental conditions. The distilled water used in the experiments at 25 °C produces hydrogen at a rate of 0.05 μmol/min, which increases to 0.066 μmol/min at 70 °C. The tap water gives hydrogen production rates ranging from 0.044 μmol/min at 25 °C to 0.06 μmol/min at 70 °C. The lake water produces hydrogen at rates between 0.036 μmol/min and 0.054 μmol/min, while the wastewater ranges from 0.028 μmol/min to 0.044 μmol/min. The present study investigates the effect of CO 2 injection into the sonoreactor on the system performance and shows that hydrogen production rates increase over a 20-min period for the water resources, with higher CO 2 flow rates leading to improved production rates. These findings demonstrate the potential of ultrasound technology for eco-friendly hydrogen production, marking a promising alternative to conventional methods and contributing valuable insights to the field of sustainable energy. [Display omitted] • The study investigates an innovative sonic method of hydrogen generation. • The present system is proposed for clean hydrogen generation. • The experiments are conducted at a frequency of 40 kHz and power of 100 ± 10 W. • The hydrogen generation is tested under various water sources at different temperatures. • The hydrogen generation is assessed by injecting CO 2 into the sonoreactor solution. [ABSTRACT FROM AUTHOR]

A reverse flow porous medium reactor with premixed and non-premixed flames was experimentally investigated to evaluate the influence of steam and carbon dioxide on methane (CH 4) filtration combustion for syngas production. Premixed, non-premixed, and non-premixed with steam were the tested cases for different injection configurations. Thermal profiles, combustion products, hydrogen (H 2) and carbon monoxide (CO) yields for several equivalence ratios are analyzed. Non-premixed case exposed higher maximum temperatures due to the reactant accumulation at the crosswise injection position, with a temperature of 1615 K. The lack of homogenization of the reactants in this configuration leads to low H 2 and high CO concentrations compared to the premixed case. The maximum CO yield was 92.81% for the non-premixed configuration with alternated air injection, while the maximum H 2 yield was 37.8% for the premixed air-methane-steam case. It was found that the air-methane-carbon dioxide mixtures had lower temperatures, combustion wave velocities, and H 2 and CO concentrations, compared to the air-methane, and air-methane-steam mixtures, but higher CH 4 and CO 2 concentrations. The premixed configuration with air-methane-carbon dioxide mixture showed higher temperatures, and H 2 and CO concentrations, compared to the non-premixed configuration. Further studies are necessary to optimize the operation of these types of reactors. • Methane filtration combustion in a reversal flow porous media reactor. • Steam and carbon dioxide on the methane filtration combustion were investigated. • Thermal profiles, and hydrogen and carbon monoxide production were analyzed. • Premixed flames showed higher H 2 and CO production than non-premixed flames. [ABSTRACT FROM AUTHOR]

Seawater carbonate chemistry observations are increasingly necessary to study a broad array of oceanographic challenges such as ocean acidification, carbon inventory tracking, and assessment of marine carbon dioxide removal strategies. The uncertainty in a seawater carbonate chemistry observation comes from unknown random variations and systematic offsets. Here, we estimate the magnitudes of these random and systematic components of uncertainty for the discrete open‐ocean carbonate chemistry measurements in the Global Ocean Data Analysis Project 2022 update (GLODAPv2.2022). We use both an uncertainty propagation approach and a carbonate chemistry measurement “inter‐consistency” approach that quantifies the disagreement between measured carbonate chemistry variables and calculations of the same variables from other carbonate chemistry measurements. Our inter‐consistency analysis reveals that the seawater carbonate chemistry measurement community has collected and released data with a random uncertainty that averages about 1.7 times the uncertainty estimated by propagating the desired “climate‐quality” random uncertainties. However, we obtain differing random uncertainty estimates for subsets of the available data, with some subsets seemingly meeting the climate‐quality criteria. We find that seawater pH measurements on the total scale do not meet the climate‐quality criteria, though the inter‐consistency of these measurements improves (by 38%) when limited to the subset of measurements made using purified indicator dyes. We show that GLODAPv2 adjustments improve inter‐consistency for some subsets of the measurements while worsening it for others. Finally, we provide general guidance for quantifying the random uncertainty that applies for common combinations of measured and calculated values. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO2 is an important way to achieve carbon neutrality, and much effort has been devoted to the design of active sites. Apart from elevating the intrinsic activity, expanding the functionality of active sites may also boost catalytic performance. Here we designed "negatively charged Ag (nc‐Ag)" active sites featuring both the intrinsic activity and the capability of regulating microenvironment, through modifying Ag nanoparticles with atomically dispersed Sn species. Different from conventional active sites (which only mediate the surface processes by bonding with the intermediates), the nc‐Ag sites could also manipulate environmental species. Therefore, the sites could not only activate CO2, but also regulate interfacial H2O and CO2, as confirmed by operando spectroscopies. The catalyst delivers a high current density with a CO faradaic efficiency of 97 %. Our work here opens up new opportunities for the design of multifunctional electrocatalytic active sites. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction reaction (CO2RR) is an appealing method for carbon utilization. Alkaline CO2 electrolyzers exhibit high CO2RR activity, low full‐cell voltages, and cost‐effectiveness. However, the issue of CO2 loss caused by (bi)carbonate formation leads to excessive energy consumption, rendering the process economically impractical. In this study, we propose a trilayer polymer electrolyte (TPE) comprising a perforated anion exchange membrane (PAEM) and a bipolar membrane (BPM) to facilitate alkaline CO2RR. This TPE enables the coexistence of high alkalinity near the catalyst surface and the H+ flux at the interface between the PAEM and the cation exchange layer (CEL) of the BPM, conditions favoring both CO2 reduction to multicarbon products and (bi)carbonate removal in KOH‐fed membrane electrode assembly (MEA) reactors. As a result, we achieve a Faradaic efficiency (FE) of approximately 46 % for C2H4, corresponding to a C2+ FE of 64 % at 260 mA cm−2, with a CO2‐to‐C2H4 single‐pass conversion (SPC) of approximately 32 % at 140 mA cm−2—nearly 1.3 times the limiting SPC in conventional AEM‐MEA electrolyzers. Furthermore, coupling CO2 reduction with formaldehyde oxidation reaction (FOR) in the TPE‐MEA electrolyzer reduces the full‐cell voltage to 2.3 V at 100 mA cm−2 without compromising the C2H4 FE. [ABSTRACT FROM AUTHOR]

In conjunction with the pressing global issue of climate change and the associated concern over global warming, increasing interest has emerged in the exploration of carbon dioxide (CO2) as a resource for the generation of a diverse array of products intended to serve societal needs. This study presents the development of an ATP-free and NAD-balanced in vitro synthetic enzymatic biosystem (ivSEB), which comprises only five cascade thermophilic enzymes, designed for the synthesis of L-malate through CO2 fixation powered by the utilization of D-glucose as a substrate. This designed ivSEB yields two moles of L-malate from one mole of D-glucose and two moles of CO2. Through meticulous refinement of reaction conditions and enzyme loading amounts, this ivSEB has demonstrated its capability to produce 6.85 mM of L-malate via CO2 fixation from an initial 5 mM of D-glucose with a molar product yield of 68.5%, and 2.45 mM of L-lactate as a byproduct. In the pursuit of assessing the industrial feasibility of this ivSEB, the study further subjected the system to the utilization of a high concentration (45.70 mM) of D-glucose. Although this endeavor necessitates additional optimization for enhanced efficiency, the present findings herald the emergence of an alternative avenue for the sustainable production of L-malate through CO2 fixation, thus bearing substantial promise for addressing ecological and industrial imperatives. [ABSTRACT FROM AUTHOR]

Hollow fibre membrane (HFM) is favourable for carbon dioxide (CO2) due to its high packing density and high volume to area ratio. In this study, the effect of air gap and bore fluid ratio is explored to study its influence on the morphology and separation performance. With high dope extrusion rate (DER), the shear‐induced polymer orientation can be preserved with low air gap which come with the cost of deformed lumen. As such, the coagulant activity of the bore fluid can be reduced by introducing solvent, which in turn reduces rate of phase inversion to prevent sudden contraction of polymer at low air gap, thus allowing proper formation of lumen. With the presence of solvent, the flowability of the dope solution increased due to reduced viscosity as the bore fluid with high solvent content make contact the external coagulant. HFM spun with low air gap with the presence of solvent in the bore fluid shows increased stretched ratio due to the influence of gravitational pull upon being extruded from the spinneret. This in turn improved the polymer chain orientation due to the stretch across the spinning line. Subsequently, HFM spun with 80 wt.% of N‐methyl‐2‐pyrollidone (NMP) in the bore fluid using narrow gap spinneret with 5‐cm air gap shows the highest ideal CO2/N2 and CO2/CH4 selectivity at 23.4 and 28 respectively, even though it also exhibit the lowest CO2 permeance at only 3.1 GPU which was ascribed to the formation of dense skin layer. Meanwhile, when HFM was spun with a bigger annulus gap, the ideal CO2/N2 and CO2/CH4 selectivity slightly dropped, however the CO2 permeance exhibit increment. [ABSTRACT FROM AUTHOR]

Developing efficient photocatalysts with low cost, high performance, and high selectivity is essential and imperative for CO 2 conversion and utilization, yet it remains a big challenge. Herein, a novel Ce-doped TiO 2 aerogel with oxygen vacancy anchored on the oriented carbonaceous (Ce–TiO 2 @CS) is synthesized by the sol-gel technique, combined with the freeze casting, supercritical drying technique, and heat treatment processes. The Ce–TiO 2 @CS aerogel has a typical aerogel-like structure, with the Ce–TiO 2 aerogel anchored on the oriented porous carbon, rendering a large BET-specific surface area of 124 m2/g, which leads to enhanced photocatalytic activity. The Ce-doping into the pristine TiO 2 results in impurity levels within the band gap, which extends the light response range to the visible light region. In addition, the rapid combination of electrons and holes is prevented via the two-phase microstructures and rapid transfer rate of electrons within the oriented porous carbon. The yields of CH 4 and CO are as high as 9.45 μmol h−1 g−1 and 42.26 μmol h−1 g−1, respectively, which are 28.6 and 2.46 times higher than those of pristine TiO 2 aerogel under simulated solar spectrum conditions without any sacrificial agents or co-catalysts, The density functional theory (DFT) calculation shows that larger C–O bonds of CO 2 molecule and more negative adsorption energy have occurred on the Ce–TiO 2 @CS aerogel, indicating that the CO 2 activation has been enhanced, which greatly improves the CO 2 photoreduction activity. This work may guide the designing of aerogel-based photocatalysts for CO 2 photocatalytic reduction. [ABSTRACT FROM AUTHOR]

The development of multi-functional and highly mixed ionic-electronic conductive perovskite oxide-based electrodes is becoming an established trend for designing and developing SOFC/SOEC reversible cells. Ideally, the same material can be employed at both electrodes provided that structural stability, high conductivity and catalytic activity are preserved in different operational atmospheres. Here, controlled Fe substitution with a small extent (0.5 mol%) of platinum at the B-site of a lanthanum strontium ferrite is proposed as an effective method to enhance the original oxide properties as both air and fuel electrode for solid oxide cells. The effects of low Pt-doping on La 0.6 Sr 0.4 FeO 3-δ structure, morphology and electrocatalytic activity are investigated and discussed. La 0.6 Sr 0.4 Fe 0.995 Pt 0.005 O 3-δ (05P-LSF) is first tested as air electrode, displaying lower area specific resistance as compared to the Pt-free perovskite. 05P-LSF structural stability and conductivity are assessed in 100 % CO 2 and 50 % CO 2 –50 % CO environments. Symmetric devices are then tested as SOECs in 100 % CO 2 , obtaining a current density output of 1.08 A/cm2 at 1.5 V. Electrochemical impedance spectroscopy (EIS) with distribution of relaxation times analysis (DRT) are used to provide insights on the electrode operation. Pt nanoparticle exsolution at the fuel electrode is induced by voltage application. The device stability under applied voltage is assessed for over 120 h. SOFC/SOEC characterization in a 50 % CO 2 /50 % CO mixture at 850 °C is also provided, obtaining a maximum power density of 270 mW/cm2 in SOFC mode, and a current density of 0.91 A/cm2 at 1.5 V in SOEC mode. [ABSTRACT FROM AUTHOR]

Leveraging electrochemistry, a new synthesis of non‐natural derivatives of itaconic acid is proposed by utilizing carbon dioxide (CO2) as a valuable C1 synthon. An electrochemical cross‐electrophile coupling between allenoates and CO2 was targeted, allowing for the synthesis of both mono‐ and di‐carboxylation products in a catalyst‐ and additive‐free environment (yields up to 87 %, 30 examples). Elaboration of the model mono‐carboxylation product, and detailed cyclovoltammetric, as well as mechanistic analyses complete the present investigation. [ABSTRACT FROM AUTHOR]

The mechanistic details of the asymmetric Ni‐catalyzed reductive cyclization/carboxylation of alkenes with CO2 have been revisited using DFT methods. Emphasis was put on the enantioselectivity and the mechanistic role of Lewis acid additives and in situ formed salts. Our results show that oxidative addition of the substrate is rate‐limiting, with the formed Ni(II)‐aryl intermediate preferring a triplet spin state. After reduction to Ni(I), enantioselective cyclization of the substrate occurs, followed by inner sphere carboxylation. Our proposed mechanism reproduces the experimentally observed enantiomeric excess and identifies critical C−H/O and C−H/N interactions that affect the selectivity. Further, our results highlight the beneficial effect of Lewis acids on CO2 insertion and suggest that in situ formed salts influence if the 5‐exo or 6‐endo product will be formed. [ABSTRACT FROM AUTHOR]

Maintaining patients' temperature during surgery is beneficial since hypothermia has been linked with perioperative complications. Laparoscopic surgery involves the insufflation of carbon dioxide (CO2) into the peritoneal cavity and has become the standard in many surgical indications since it is associated with better and faster recovery. However, the use of cold and dry CO2 insufflation can lead to perioperative hypothermia. We aimed to assess the difference between intraperitoneal and core temperatures during laparoscopic surgery and evaluate the influence of duration and CO2 insufflation volume by fitting a mixed generalized additive model. In this prospective observational single-center cohort trial, we included patients aged over 17 with American Society of Anesthesiology risk scores I to III undergoing laparoscopic surgery. Anesthesia, ventilation, and analgesia followed standard protocols, while patients received active warming using blankets and warmed fluids. Temperature data, CO2 ventilation parameters, and intraabdominal pressure were collected. We recruited 51 patients. The core temperature was maintained above 36 °C and progressively raised toward 37 °C as pneumoperitoneum time passed. In contrast, the intraperitoneal temperature decreased, thus creating a widening difference from 0.4 [25th–75th percentile: 0.2–0.8] °C at the beginning to 2.3 [2.1–2.3] °C after 240 min. Pneumoperitoneum duration and CO2 insufflation volume significantly increased this temperature difference (P < 0.001 for both parameters). Core vs. intraperitoneal temperature difference increased linearly by 0.01 T °C per minute of pneumoperitoneum time up to 120 min and then 0.05 T °C per minute. Each insufflated liter per unit of time, i.e. every 10 min, increased the temperature difference by approximately 0.009 T °C. Our findings highlight the impact of pneumoperitoneum duration and CO2 insufflation volume on the difference between core and intraperitoneal temperatures. Implementing adequate external warming during laparoscopic surgery effectively maintains core temperature despite the use of dry and unwarmed CO2 gases, but peritoneal hypothermia remains a concern, suggesting the importance of further research into regional effects. Trial registration: Clinicaltrials.gov: NCT04294758. [ABSTRACT FROM AUTHOR]

Bio-based carbon dioxide removal encompasses a range of (1) natural sink enhancement concepts in agriculture and on organic soils including peatlands, and in forestry, (2) bio-based building materials, and (3) bioenergy production with CO2 capture and storage (BECCS). A common database on these concepts is crucial for their consideration in strategies and implementation. In this study, we analyse standardised factsheets on these concepts. We find different dynamics of deployment until 2045: for CO2 removal rates from the atmosphere, natural sink enhancement concepts are characterised by gradually increasing rates, followed by a saturation and potentially a decrease after few decades; forest-related measures ramp up slowly and for construction projects and bioenergy plants, annually constant removal rates are assumed during operation which drop to zero afterwards. The expenses for removing 1 t CO2 from the atmosphere were found to be between 8 and 520 € t CO2−1, which arises from high divergence both in capital and operational expenditures among the concepts. This high variability of expenses seems to suggest the more cost-effective concepts should be implemented first. However, aspects from economics, resource base and environmental impacts to social and political implications for Germany need to be considered for developing implementation strategies. All concepts investigated could be deployed on scales to significantly contribute to the German climate neutrality target. [ABSTRACT FROM AUTHOR]

The combination of microbial CO 2 reduction process and photocatalysis can meet the economic goal of sustainable carbon neutrality. Solar-energy as driven force can be achieved, by mimicking natural photosynthesis through the interaction between photo-responsive semiconductor nano-materials and electroautotrophic bacteria (EAB). Therefore, we reviewed the engineering strategies developed in recent years for photocatalytic microbial fixation of CO 2 to improve extracellular electron transfer (EET) rate and enhance the conversion efficiency of solar-to-chemical energy, including (1) the application principles of semiconductor nanomaterials in microbial CO 2 reduction systems; (2) photocathode; (3) photoanode; (4) dual photoelectrodes and (5) inorganic-microbe hybrid system; (6) perspectives on future challenges and opportunities for photocatalytic microbial fixation of CO 2 for sustainable energy and chemical production. This review will provide a theoretical basis for the future development of photocatalytic microbial fixation of CO 2 in energy harvesting, CO 2 fixation, and chemical synthesis. [ABSTRACT FROM AUTHOR]

Constructing the interface of Ni/Y 2 O 3 heterogeneous catalyst is a feasible strategy for efficient catalyst design in CO 2 methanation, which can create the active Y–O–Ni interfacial sites by utilizing the interaction between Ni and Y 2 O 3. In this work, the strategy of using different nickel precursors (nickel nitrate, nickel acetate, basic nickel carbonate and nickel citrate) was used to prepare various Ni-based catalysts supported on Y 2 O 3 , which were estimated for their catalytic performance on CO 2 methanation. The catalysts were characterized based on BET, XRD, TEM, H 2 -TPR, XPS and CO 2 -TPD, etc. The results indicated a close correlation between the metal dispersion and particle size of Ni/Y 2 O 3 catalysts and the nickel precursor employed. The Y–O–Ni interface structure in Ni/Y 2 O 3 catalysts, associated with basic sites, provides a richer source of basic sites, offering more active sites for CO 2 adsorption and activation. Ni/Y 2 O 3 catalyst prepared with nickel nitrate as the precursor exhibited characteristics such as a highly enhanced nickel dispersion, a smaller nickel particle size, and more abundant metallic Ni0 sites. Moreover, nickel nitrate-derived Ni/Y 2 O 3 catalyst exhibited optimal catalytic activity, achieving a CO 2 conversion rate of up to 92 % at 300 °C, with 100 % selectivity to CH 4 , and displaying good stability over 30 h. Therefore, the dispersion of Ni and the size of Ni particles could be controlled by adjusting the precursor, which is closely associated with the catalytic activity of Ni/Y 2 O 3 catalyst. This work unveils the interface-property relationship of Ni/Y 2 O 3 catalysts and provides a new insight into strategy of constructing more effective Ni-based catalyst for CO 2 methanation through the controlled nickel precursor. [Display omitted] • The catalytic performance and properties of Ni/Y 2 O 3 is influenced by the Ni precursor in CO 2 methanation. • Ni–N exhibits superior activity at 300 °C achieving a CO 2 conversion of 92 % at 300 °C, with 100 % selectivity to CH 4. • The nickel precursor influences the particle size of Ni and the metal-support interaction. • The Y–O–Ni interface structure in Ni/Y 2 O 3 is associated with basic and metallic Ni sites. [ABSTRACT FROM AUTHOR]