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River networks represent the largest biogeochemical nexus between the continents, ocean and atmosphere. Our current understanding of the role of rivers in the global carbon cycle remains limited, which makes it difficult to predict how global change may alter the timing and spatial distribution of riverine carbon sequestration and greenhouse gas emissions. Here we review the state of river ecosystem metabolism research and synthesize the current best available estimates of river ecosystem metabolism. We quantify the organic and inorganic carbon flux from land to global rivers and show that their net ecosystem production and carbon dioxide emissions shift the organic to inorganic carbon balance en route from land to the coastal ocean. Furthermore, we discuss how global change may affect river ecosystem metabolism and related carbon fluxes and identify research directions that can help to develop better predictions of the effects of global change on riverine ecosystem processes. We argue that a global river observing system will play a key role in understanding river networks and their future evolution in the context of the global carbon budget., (© 2023. Springer Nature Limited.)

This article presents an algorithm for modelling an Adaptive Neuro Fuzzy Inference System (ANFIS) for power transformer paper conditions in order to estimate the transformer's expected life. The dielectric characteristics, dissolved gasses, and furfural of 108 running transformers were collected, which were divided into 76 training datasets and another 32 testing datasets. The degree of polymerization (DP) of the transformer paper was predicted using the ANFIS model based on using the dielectric characteristics and dissolved gases as input. These inputs were analyzed, and the best combination was selected, whereas CO + CO2, acidity, interfacial tension, and color were correlated with the paper's deterioration condition and were chosen as the input variables. The best combination of input variables and membership function was selected to build the optimal ANFIS model, which was then compared and evaluated. The proposed ANFIS model has 89.07% training accuracy and 85.75% testing accuracy and was applied to a transformer paper insulation assessment and an estimation of the expected life of four Indonesian transformers for which furfural data is unavailable. This proposed algorithm can be used as a furfural alternative for the general assessment of transformer paper conditions and the estimation of expected life and provides a helpful assistance for experts in transformer condition assessment. [ABSTRACT FROM AUTHOR]

The capture and use of carbon dioxide to create valuable products might lower the net costs of reducing emissions or removing carbon dioxide from the atmosphere. Here we review ten pathways for the utilization of carbon dioxide. Pathways that involve chemicals, fuels and microalgae might reduce emissions of carbon dioxide but have limited potential for its removal, whereas pathways that involve construction materials can both utilize and remove carbon dioxide. Land-based pathways can increase agricultural output and remove carbon dioxide. Our assessment suggests that each pathway could scale to over 0.5 gigatonnes of carbon dioxide utilization annually. However, barriers to implementation remain substantial and resource constraints prevent the simultaneous deployment of all pathways.

We report herein the preparation and characterization of six readily assembled bis-coordinated homoleptic silver(I) N,N′-bis(arylimino)acenaphthene (BIAN) complexes of general structure [Ag(I)(BIAN)2]BF4 and the influence of the electronic properties of the ligand substitution pattern on their performance in electrochemical CO2 reduction (CO2R). All the explored catalysts displayed substantial current enhancements in carbon-dioxide-saturated solvents dependent on the ligated BIAN and no significant concurrent H2 evolution when utilizing 2% H2O as a proton source. Additionally, preliminary studies, employing a drop-casted ink of 0.4 mg cm−2 [Ag(I)(4-OMe-BIAN)2]BF4 (Ag4) immobilized onto carbon paper gas diffusion electrodes in a flow cell with 1M KHCO3 aqueous electrolyte, resulted in a propitious Faradaic efficiency of 51% for CO at a current density of 50 mA cm−2. [ABSTRACT FROM AUTHOR]

The amount of China's sulfur dioxide emission remains significantly large in recent years. To further reduce sulfur dioxide emission, the key is to find out the leading factors affecting sulfur dioxide emission and then take measures to control it accordingly. In order to investigate the influential factors of sulfur dioxide emission of various provinces, the data of sulfur dioxide emission of 30 provinces in China from 2001 to 2020 were collected. We established the symbolic regression model to explore the relationship between the GDP (x 1 ), total population (x 2 ), total energy consumption (x 3 ), thermal power installed capacity (x 4 ), and sulfur dioxide emission (dependent variable) for each province. The results show that the amount of China's total sulfur dioxide emission and sulfur dioxide emission in most provinces meet the environmental Kuznets curve (EKC). The influential degree of the factors affecting China's sulfur dioxide emission are GDP, total energy consumption, thermal power installed capacity, and total population. The provinces with the primary factor of GDP have the lowest average total energy consumption and average thermal power installed capacity, and their average sulfur dioxide emissions are also relatively low. The provinces with the primary factor of GDP do not show obvious geographical characteristics, but the provinces with the primary factor of total energy consumption are all distributed in southern China. Based on the research results, some control measures are also put forward., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

This study analyzes the impact of globalization and income on ecological footprint over the period of 1970 to 2018 in the five highly globalized countries of the European Union ranked by the KOF index. To this end, the study uses a Fourier autoregressive distributed lag cointegration and Fourier Toda-Yamamoto causality methods. Studies that examine the effects of globalization on environmental degradation often neglect structural changes, which can lead to biased results. Using Fourier approximations, this study is the first to conduct an environmental assessment incorporating smooth structural changes for the five highly globalized countries of the European Union. The results show that (i) cointegration exists in Switzerland, Sweden, the Netherlands, Austria, and Denmark. (ii) The EKC hypothesis is valid for Switzerland and Denmark, while in Sweden and Austria, there is a U-shaped relationship between income and ecological footprint. (iii) The turning point at which income improves environmental quality is $68,191 for Switzerland and $46,600 for Denmark, and both countries have exceeded this per capita income level. (iv) Globalization is a factor that promotes environmental sustainability in Switzerland and the Netherlands. In order to regulate and manage environmental issues effectively, policy-makers should take advantage of economic development in Switzerland and Denmark as well as globalization in the Netherlands and Switzerland., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Building energy intensity (BEI) has been used to assess a building's overall energy performance. However, the energy performance, CO 2 footprint and electricity costs due to lighting in buildings are currently required to assist relevant authorities to develop, revise and implement energy-efficient lighting policies that are effective and acceptable for the country. This work presents an estimation approach for lighting in commercial buildings in Southeast Asia and its decarbonisation pathway for benchmarking. Application of this approach to a selected library in Brunei Darussalam showed that an energy-efficient light-emitting diode (LED) lighting system would make the building greener. We projected reductions in lighting energy consumption by 6.7 times (3.98 kWh/m 2 /year), its associated CO 2 emissions by 8 times (0.59 kg CO 2 /m 2 /year) and electricity costs by 8.7 times (B$7.07/m 2 /year) by 2050 if existing lamps in the library are retrofitted with LED lamps., (© 2022. The Author(s).)

This paper presents a critical review of laser pyrolysis. Although this technology is almost 60 years old, in literature many researchers, both from academia and industry, are still developing and improving it. On the contrary industrial applications are struggling to take off, if not in very restricted areas, although the technology has undoubted advantages that justify future development. The aim of this work consists in analysing a representative pool of scientific papers (230) and patents (121), from the last 20 years, to have an overview about the evolution of the method and try to understand the efforts spent to improve this technology effectively in academia and in industry. This study is important to provide a complete review about the argument, still missing in the literature. The objective is to provide an overview sufficiently broad and representative in the sources and to capture all the main ways in which laser pyrolysis has been used and with what distribution. The main focuses of the study are the analyses of the functions carried out by laser technologies, the application fields, and the types of used laser (i.e. models, power and fluence). Among the main results, the study showed that the main use of laser pyrolysis is to produce nanoparticles and coatings, the main materials worked by laser pyrolysis are silicon and carbon dioxide and the main searched properties in the products of laser pyrolysis are catalysts activity and electrical conductivity. CO2 lasers are the most used and the have high versatility compared to others. In conclusion, the study showed that laser pyrolysis is a consolidated technology within its main application fields (nanoparticles and coatings) for several years. Within this context, the technology has been developed on very different sizes and processes, obtaining a very wide range of results. Finally, these results may also have stimulated new areas of experimentation that emerged mainly in recent years and which concern biomedical applications, additive manufacturing, and waste disposal. [ABSTRACT FROM AUTHOR]

This study evaluates the chemo-mechanical influence of injected CO 2 on the Morrow B sandstone reservoir and the upper Morrow shale caprock utilizing data from the inverted 5-spot pattern centered on Well 13-10A within the Farnsworth unit (FWU). This study also seeks to evaluate the integrity of the caprock and the long-term CO 2 storage capability of the FWU. The inverted 5-spot pattern was extracted from the field-scale model and tuned with the available field observed data before the modeling work. Two coupled numerical simulation models were utilized to continue the study. First, a coupled hydro-geochemical model was constructed to simulate the dissolution and precipitation of formation minerals by modeling three intra-aqueous and six mineral reactions. In addition, a coupled hydro-geomechanical model was constructed and employed to study the effects of stress changes on the caprock's porosity, permeability, and ground displacement. The Mohr-Coulomb circle and failure envelope were used to determine caprock failure. In this work, the CO 2 -WAG injection is followed by the historical field-observed strategy. During the forecasting period, a Water Alternating Gas (WAG) injection ratio of 1:3 was utilized with a baseline bottom-hole pressure constraint of 5500 psi for 20 years. A post-injection period of 1000 years was simulated to monitor the CO 2 plume and its effects on the CO 2 storage reservoir and caprock integrity. The simulation results indicated that the impacts of the geochemical reactions on the porosity of the caprock were insignificant as it experienced a decrease of about 0.0003% at the end of the 1000-year post-injection monitoring. On the other hand, the maximum stress-induced porosity change was about a 1.4% increase, resulting in about 4% in permeability change. It was estimated that about 3.3% of the sequestered CO 2 in the formation interacted with the caprock. Despite these petrophysical property alterations and CO 2 interactions in the caprock, the caprock still maintained its elastic properties and was determined to be far from its failure., (© 2022. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Decarbonization strategies for the cement and concrete sector have relied heavily on supply-side technologies, including carbon capture and storage (CCS), masking opportunities for demand-side intervention. Here we show that cross-cutting strategies involving both the supply and demand sides can achieve net-zero emissions by 2050 across the entire Japanese cement and concrete cycle without resorting to mass deployment of CCS. Our analysis shows that a series of mitigation efforts on the supply side can reduce 2050 CO 2 emissions by up to 80% from baseline levels and that the remaining 20% mitigation gap can be fully bridged by the efficient use of cement and concrete in the built environment. However, this decarbonization pathway is dependent on how CO 2 uptake by carbonation and carbon capture and utilization is accounted for in the inventory. Our analysis underscores the importance of including demand-side interventions at the heart of decarbonization strategies and highlights the urgent need to discuss how to account for CO 2 uptake in national inventories under the Paris Agreement., (© 2022. The Author(s).)

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As a part of our research in the field of thermochemical energy storage, this study aims to investigate the potential of three fly ash samples derived from the fluidized bed reactors of three different pulp and paper plants in Austria for their use as thermochemical energy (TCES) and CO2 storage materials. The selected samples were analyzed by different physical and chemical analytical techniques such as X-ray fluorescence spectroscopy (XRF), X-ray diffraction (XRD), particle size distribution (PSD), scanning electron microscopy (SEM), inductively coupled plasma atomic emission spectroscopy (ICP-OES), and simultaneous thermal analysis (STA) under different atmospheres (N2, CO2, and H2O/CO2). To evaluate the environmental impact, leaching tests were also performed. The amount of CaO as a promising candidate for TCES was verified by XRF analysis, which was in the range of 25–63% (w/w). XRD results indicate that the CaO lies as free lime (3–32%), calcite (21–29%), and silicate in all fly ash samples. The results of STA show that all fly ash samples could fulfill the requirements for TCES (i.e., charging and discharging). A cycling stability test of three cycles was demonstrated for all samples which indicates a reduction of conversion in the first three reaction cycles. The energy content of the examined samples was up to 504 kJ/kg according to the STA results. More energy (~1090 kJ/kg) in the first discharging step in the CO2/H2O atmosphere could be released through two kinds of fly ash samples due to the already existing free lime (CaO) in those samples. The CO2 storage capacity of these fly ash samples ranged between 18 and 110 kg per ton of fly ash, based on the direct and dry method. The leaching tests showed that all heavy metals were below the limit values of the Austrian landfill ordinance. It is viable to say that the valorization of fly ash from the pulp and paper industries via TCES and CO2 storage is plausible. However, further investigations such as cycling stability improvement, system integration and a life cycle assessment (LCA) still need to be conducted. [ABSTRACT FROM AUTHOR]

Research reported during the past decade has shown that global warming is roughly proportional to the total amount of carbon dioxide released into the atmosphere. This makes it possible to estimate the remaining carbon budget: the total amount of anthropogenic carbon dioxide that can still be emitted into the atmosphere while holding the global average temperature increase to the limit set by the Paris Agreement. However, a wide range of estimates for the remaining carbon budget has been reported, reducing the effectiveness of the remaining carbon budget as a means of setting emission reduction targets that are consistent with the Paris Agreement. Here we present a framework that enables us to track estimates of the remaining carbon budget and to understand how these estimates can improve over time as scientific knowledge advances. We propose that application of this framework may help to reconcile differences between estimates of the remaining carbon budget and may provide a basis for reducing uncertainty in the range of future estimates.

The ocean's ability to sequester carbon away from the atmosphere exerts an important control on global climate. The biological pump drives carbon storage in the deep ocean and is thought to function via gravitational settling of organic particles from surface waters. However, the settling flux alone is often insufficient to balance mesopelagic carbon budgets or to meet the demands of subsurface biota. Here we review additional biological and physical mechanisms that inject suspended and sinking particles to depth. We propose that these 'particle injection pumps' probably sequester as much carbon as the gravitational pump, helping to close the carbon budget and motivating further investigation into their environmental control.

Atmospheric carbon dioxide (CO 2 ) levels are currently at 418 parts per million (ppm), and by 2100 may exceed 900 ppm. The biological effects of lifetime exposure to CO 2 at these levels is unknown. Previously we have shown that mouse lung function is altered by long-term exposure to 890 ppm CO 2 . Here, we assess the broader systemic physiological responses to this exposure. Mice were exposed to either 460 or 890 ppm from preconception to 3 months of age, and assessed for effects on developmental, renal and osteological parameters. Locomotor, memory, learning and anxiety-like behaviours of the mice were also assessed. Exposure to 890 ppm CO 2 increased birthweight, decreased female body weight after weaning, and, as young adults, resulted in reduced engagement in memory/learning tasks, and hyperactivity in both sexes in comparison to controls. There were no clear anxiety, learning or memory changes. Renal and osteological parameters were minimally affected. Overall, this study shows that exposure of mice to 890 ppm CO 2 from preconception to young adulthood alters growth and some behaviours, with limited evidence of compensatory changes in acid-base balance. These findings highlight the potential for a direct effect of increased atmospheric CO 2 on mammalian health outcomes. KEY POINTS: Long-term exposure to elevated levels of atmospheric CO 2 is an uncontrolled experiment already underway. This is the first known study to assess non-respiratory physiological impacts of long-term (conception to young adulthood) exposure of mice to CO 2 at levels that may arise in the atmosphere due to global emissions. Exposure to elevated CO 2 , in comparison to control mice, altered growth patterns in early life and resulted in hyperactive behaviours in young adulthood. Renal and bone parameters, which are important to balance acid-base levels to compensate for increased CO 2 exposure, remained relatively unaffected. This work adds to the body of evidence regarding the effects of carbon emissions on mammalian health and highlights a potential future burden of disease., (© 2021 The Authors. The Journal of Physiology © 2021 The Physiological Society.)

In order to improve the whiteness of fly ash, the particles were coated by in-situ precipitation of calcium carbonate. After different mass ratios of calcium oxide to fly ash were mixed into water, a certain amount of carbon dioxide was bubbled into the mixture to form a precipitated calcium carbonate deposit on the surface of fly ash. With the help of scanning electron microscopy (SEM), the process and the coating mechanism of the unmodified and modified fly ash were studied. The results showed that when a 1:1 mass ratio of calcium oxide to fly ash was implemented, the whiteness of fly ash was increased from 30.3 (the original fly ash) to 74.0 (the modified fly ash). After appropriately controlling for the rate of carbon dioxide, the whiteness was improved to meet the standard for filler in the papermaking industry, and also great advantages in paper physical strength were demonstrated. [ABSTRACT FROM AUTHOR]

Hydrogen Economy and Cyclic Economy are advocated, together with the use of perennial (solar, wind, hydro, geo-power, SWHG) and renewable (biomass) energy sources, for defossilizing anthropic activities and mitigating climate change. Each option has intrinsic limits that prevent a stand-alone success in reaching the target. Humans have recycled goods (metals, water, paper, and now plastics) to a different extent since very long time. Recycling carbon (which is already performed at the industrial level in the form of CO 2 utilization and with recycling paper and plastics) is a key point for the future. The conversion of CO 2 into chemicals and materials is carried out since the late 1800s (Solvay process) and is today performed at scale of 230 Mt/y. It is time to implement on a scale of several Gt/y the conversion of CO 2 into energy products, possibly mimicking Nature which does not use hydrogen. In the short term, a few conditions must be met to make operative on a large scale the production of fuels from recycled-C, namely the availability of low-cost: i. abundant, pure concentrated streams of CO 2 , ii. non-fossil primary energy sources, and iii. non-fossil-hydrogen. The large-scale production of hydrogen by Methane Steam Reforming with CO 2 capture (Blue-H 2) seems to be a realistic and sustainable solution. Green-H 2 could in principle be produced on a large scale through the electrolysis of water powered by perennial primary sources, but hurdles such as the availability of materials for the construction of long-living, robust electrochemical cells (membranes, electrodes) must be abated for a substantial scale-up with respect to existing capacity. The actual political situation makes difficult to rely on external supplies. Supposed that cheap hydrogen will be available, its direct use in energy production can be confronted with the indirect use that implies the hydrogenation of CO 2 into fuels (E-fuels), an almost ready technology. The two strategies have both pros and cons and can be integrated. E-Fuels can also represent an option for storing the energy of intermittent sources. In the medium-long term, the direct co-processing of CO 2 and water via co-electrolysis may avoid the production/transport/ use of hydrogen. In the long term, coprocessing of CO 2 and H 2 O to fuels via photochemical or photoelectrochemical processes can become a strategic technology. • Hydrogen Economy and Cyclic Economy are discussed as an option for defossilizing anthropic activities and mitigating climate change. • In the short term, a few conditions must be met to make operative on a large scale the production of fuels from recycled-C. • In the medium-long term, the direct co-processing of CO 2 and water via co-electrolysis may avoid the production/transport/ use of hydrogen. • In the long term, coprocessing of CO 2 and H 2 O to fuels via photochemical or photoelectrochemical processes can become a strategic technology. [ABSTRACT FROM AUTHOR]

Carbon capture and storage (CCS) is a key technology to mitigate the environmental impact of carbon dioxide (CO 2 ) emissions. An understanding of the potential trapping and storage mechanisms is required to provide confidence in safe and secure CO 2 geological sequestration 1,2 . Depleted hydrocarbon reservoirs have substantial CO 2 storage potential 1 , 3 , and numerous hydrocarbon reservoirs have undergone CO 2 injection as a means of enhanced oil recovery (CO 2 -EOR), providing an opportunity to evaluate the (bio)geochemical behaviour of injected carbon. Here we present noble gas, stable isotope, clumped isotope and gene-sequencing analyses from a CO 2 -EOR project in the Olla Field (Louisiana, USA). We show that microbial methanogenesis converted as much as 13-19% of the injected CO 2 to methane (CH 4 ) and up to an additional 74% of CO 2 was dissolved in the groundwater. We calculate an in situ microbial methanogenesis rate from within a natural system of 73-109 millimoles of CH 4 per cubic metre (standard temperature and pressure) per year for the Olla Field. Similar geochemical trends in both injected and natural CO 2 fields suggest that microbial methanogenesis may be an important subsurface sink of CO 2 globally. For CO 2 sequestration sites within the environmental window for microbial methanogenesis, conversion to CH 4 should be considered in site selection., (© 2021. The Author(s).)

The article offers information on people with chronic obstructive pulmonary disease, initiation of nocturnal non-invasive ventilation at home is non-inferior to initiation during a hospital admission.

Trying to understand how the interdependence relationship among the sectors of a given economy and its impacts on the environment is fundamental to the identification of sectors that are more polluting and those that are considered key in the sense of being less polluting. In order to describe this relationship, this work has as general objective to measure the level of CO2 emission from the level of production in function of the consumption of electric energy in the state of Mato Grosso do Sul. In order to meet the general objective, from the state energy balance and the input–output matrix of 2010, a hybrid input–output matrix was derived. Thus, it was possible to identify that the service sector, although is the engine of the state GDP, represents only 16% of the emissions, agriculture and cattle raising 6% and industry 78%. The main sectors in CO2 emission are rubber and plastic articles and the pulp and paper production sector. Considering the estimates of growth of the state, the concern with the environment is emphasized as the driving sectors of the expansion being precisely those that emit more CO2. [ABSTRACT FROM AUTHOR]

Several studies have quantified the carbon dioxide (CO 2) emissions associated with energy consumption, agriculture value added, food crop production, forest covered area, and forest production in various countries. However, past studies have ignored the long-term and short-term effects of these factors on CO 2 . This study used data from 1980 to 2018 and applied the autoregressive distributed lag model (ARDL) technique to test long-run and short-run effects of these factors on CO 2 emission in the Pakistani context. The results revealed that in short-run food crop production, forest covered area and forest production have capacity to reduce CO 2 emission. However, in long run, energy consumption and agriculture value added along with food crop production, forest covered area, and forest production are negatively and significantly related to CO 2 emission which shows that these sectors, in long run, have capacity to mitigate emissions. Additionally, results also show that food crop production and forest covered area are more effective to reduce CO 2 emission as compared to other sectors. The robustness of the results was supported by using additional models and tests. This study provides scholars with valuable insights and also helps government authorities and policymakers to develop comprehensive strategies to reduce carbon emissions., (© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Introduction: It is difficult to estimate the ischemic consequences when using partial resuscitative endovascular balloon occlusion of the aorta (REBOA). The aim was to investigate if end-tidal carbon dioxide (ETCO2) is correlated to degree of aortic occlusion, measured as distal aortic blood flow, and distal organ metabolism, estimated as systemic oxygen consumption (VO2), in a porcine model of normovolemia and hemorrhagic shock., Materials and Methods: Nine anesthetized pigs (25-32 kg) were subjected to incremental steps of zone 1 aortic occlusion (reducing distal aortic blood flow by 33%, 66%, and 100%) during normovolemia and hemorrhagic grade IV shock. Hemodynamic and respiratory variables, and blood samples, were measured. Systemic VO2 was correlated to ETCO2 and measures of partial occlusion previously described., Results: Aortic occlusion gradually lowered distal blood flow and pressure, whereas ETCO2, VO2 and carbon dioxide production decreased at 66% and 100% aortic occlusion. Aortic blood flow correlated significantly to ETCO2 during both normovolemia and hemorrhage (R = 0.84 and 0.83, respectively) and to femoral mean pressure (R = 0.92 and 0.83, respectively). Systemic VO2 correlated strongly to ETCO2 during both normovolemia and hemorrhage (R = 0.91 and 0.79, respectively), blood flow of the superior mesenteric artery (R = 0.77 and 0.85, respectively) and abdominal aorta (R = 0.78 and 0.78, respectively), but less to femoral blood pressure (R = 0.71 and 0.54, respectively)., Conclusion: ETCO2 was correlated to distal aortic blood flow and VO2 during incremental degrees of aortic occlusion thereby potentially reflecting the degree of aortic occlusion and the ischemic consequences of partial REBOA. Further studies of ETCO2, and potential confounders, in partial REBOA are needed before clinical use., Competing Interests: The authors wish to report no conflicts of interest related to the subject matter., (Copyright © 2021 by the Shock Society.)

Strategies for changing the conductivity of Li 2 CO 3 is introduced into the fabrication of Li-CO 2 battery. Benefitting from the favorable hierarchical architecture constructed (CPM-MnO 2), facile charge transfer occurs between catalytic surface and Li 2 CO 3 by –OH⋯O hydrogen bonds improves the metallicity of Li 2 CO 3 , facilitating the formation/decomposition of Li 2 CO 3 and bestowing an ultra-long-term stability of 1087 cycles (4348 h). Taking into account its simplicity, scalable character and outstanding performance, this hierarchical composite electrode paves an effective trajectory for the future development of highly efficient cathodes for durable metal-CO 2 batteries. [Display omitted] • Excellent hierarchical structure of MXene and MnO 2 on carbon paper was fabricated. • Enriched charge transfer occurred on MXene and the MnO 2 by OH⋯O hydrogen bonding. • The prepared batteries showed an ultra-long cycle lifetime and low overpotential. • The optimized electronic structure can improve the metallicity of Li 2 CO 3. • The accelerated decomposition of discharge products promoted CRR and CER kinetics. Lithium-CO 2 batteries are recognized as an essential strategy for efficient carbon sequestration and energy storage to achieve carbon neutrality. Their cycle-ability and polarization voltage, however, are hindered by high decomposition voltage (≈4.3–4.5 V) of insulating Li 2 CO 3. Herein, we report a significant advance toward the rational design of self-supporting and ultra-long cycle lifetime cathode for Li-CO 2 batteries, dependence on a favorable hierarchical architecture and rich charge transfer constructed by homogeneously distributed MnO 2 nanoplates rooted in the MXene surface supported by carbon paper. Detailedly, it exhibits impressive ultra-long-term stability of 1087 cycles (4348 h) with a low polarization gap (≈ 0.47 V) at a high current of 200 μA cm−2, which is outperformed by all the liquid electrolyte-based Li-CO2 batteries reported previously. Electronic structure analysis reveals that facile charge transfer occurs between catalytic surface and Li 2 CO 3 , springing from the –OH functional group (in MXene) to MnO 2 by –OH⋯O hydrogen bonds, which acts as charge transfer channels, improving the metallicity of Li 2 CO 3 and facilitating its decomposition and extending battery cyclability. This work paves an effective trajectory for the future development of highly efficient cathodes for durable metal-CO 2 batteries. [ABSTRACT FROM AUTHOR]

Paper-based microfluidic devices are an attractive option for developing low-cost, point-of-care diagnostic tools. To incorporate more complex assays into paper, these devices must become more sophisticated, through the sequential delivery of different liquids or reagents without user intervention. Many flow control strategies focus on slowing the fluid down. However, this can lead to increased assay times and sample loss due to evaporation. We report the use of a CO 2 laser to create etched grooves on paper to accelerate wicking speeds in paper-based microfluidic devices. We explored different laser settings to determine the optimal configuration. Our findings showed that simply cutting a slit into the paper created the fastest wicking channels. The slit acted as a macro capillary, allowing fluid to bypass the paper and speed it up. Further studies determined an ideal groove pitch of 0.75 mm (spacing in between grooves) for a paper channel. Additional experiments documented how sealing grooved channels with different adhesives can influence wicking. Overall, sealing the channels with tape made them wick faster. However, sealing methods such as lamination had a negative effect on wicking. Laser-etched grooves were successfully used to design a fluid-handling architecture for a chemiresistive paper-based biosensor. The grooves facilitated rapid, sequential delivery of sample and wash buffer. Human serum albumin spiked in phosphate buffer, artificial urine, and artificial saliva was successfully detected at as low as 15 pM. Etching grooves in paper is a simple process that requires no additional materials or chemicals, allowing single-step fabrication of paper-based microfluidic channels. • Laser-etching through-cut grooves into paper creates the fastest wicking channels. • Wicking greatly influenced by how the paper channels are sealed. • Demonstrated sequential delivery for chemiresistive biosensor for HSA detection. [ABSTRACT FROM AUTHOR]

[Display omitted] • A bifunctional flexible Pt/TiO 2 -γ-Al 2 O 3 nanofiber paper was successfully prepared. • The PTA sample can efficiently decompose HCHO to CO 2 and H 2 O at room temperature. • PTA1 exhibited better catalytic activity and stability. • The surface coating of TiO 2 in PTA catalyst plays an important role for its performance. • The PTA sample also exhibits good filtration performance for fine particles. A flexible Pt/TiO 2 /γ-Al 2 O 3 nanfiber paper (PTA) was successfully prepared by an electrospinning-coating-NaBH 4 reduction method. The catalytic performance for formaldehyde (HCHO) oxidation over PTA with different Pt contents was investigated at room temperature. The results show that PTA exhibits higher catalytic activity and stability than Pt/γ-Al 2 O 3. The TiO 2 coating can promote the transformation of intermediate species and the desorption of CO 2. The PTA1 with 1 wt% Pt shows the best catalytic activity and good stability. In the view of activity and cost, 0.5 wt% Pt is the optimal Pt content. The TiO 2 coating not only plays an important role in improving the activity and stability of PTA, but also acts as a protective shell of γ-Al 2 O 3 fiber, which greatly reduces the risk of alkali etching during preparation and maintains the good flexibility of PTA. The dioxymethylene (DOM), formate/carbonate species, CO are the intermediate species in HCHO oxidation over PTA. In addition, PTA exhibits good filtration performance for fine particles as well as good fluid permeability. Because of the high efficiency and flexibility of PTA composite catalytic material for HCHO oxidation with good filtration performance for fine particles, it will be a promising candidate in air purification. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO 2 ) is the key atmospheric gas that controls the earth's greenhouse effect, and forests play a major role in abating the atmospheric CO 2 by storing carbon as biomass. Therefore, it is vital to understand the role of different forests in regulating the spatiotemporal dynamics of atmospheric CO 2 concentration. In this study, we have used eddy covariance (EC) tower-based atmospheric CO 2 concentration measurements and satellite-retrieved column average CO 2 concentration of 2018 to understand the diurnal and seasonal dynamics of atmospheric CO 2 concentration over the sub-tropical forest in the foothills of northwest Himalaya, Uttarakhand, India. EC study revealed that the CO 2 concentration over the forest canopy peaks during mid-night to early morning and drop to a minimum during the afternoon. On a monthly scale, peak atmospheric CO 2 concentration was observed during July in both the sites, which was a result of more release of CO 2 by the forest ecosystem through ecosystem respiration and microbial decomposition. Enhanced photosynthetic activities during the late monsoon and post-monsoon resulted in the decrease of atmospheric CO 2 concentration over the forest ecosystem. Among the meteorological variables, rainfall was found to have the highest control over the seasonal variability of the atmospheric CO 2 concentration. Orbiting Carbon Observatory-2 (OCO-2) satellite-retrieved column average CO 2 (XCO 2 ) was also examined to comprehend its reliability on an ecosystem scale. The OCO-2 retrieved XCO 2 value was higher than the EC carbon flux tower-measured atmospheric CO 2 concentration, which might be due to differences in the vertical resolution of the CO 2 column and scale difference. However, the monthly atmospheric XCO 2 retrieved from OCO-2 strongly adheres with the ground-measured monthly pattern. Our study highlights that forests with varying functional traits within the same climatic conditions show variability in the regulation of atmospheric CO 2 concentration.

The production of high-yield pulp in China has increased significantly in recent years. The well-known advantages of this type of pulp include low production cost, high opacity, and good paper formation. In the context of state-of-the-art technologies, China's high-yield pulping, which is dominated by the PRC-APMP (preconditioning refiner chemical treatment-alkaline peroxide mechanical pulping) process, has a much higher energy input but a significantly lower wood consumption in comparison with the kraft pulping process. If the saved wood in the forest or plantation is considered as an increment of carbon storage, then the carbon dioxide emission from the production of high-yield pulp can be regarded as much lower than that of kraft pulp. [ABSTRACT FROM AUTHOR]

Key Points: Dynamic cerebral autoregulation (CA) is often expressed by the mean arterial blood pressure (MAP)-cerebral blood flow (CBF) relationship, with little attention given to the dynamic relationship between MAP and cerebrovascular resistance (CVR). In CBF velocity (CBFV) recordings with transcranial Doppler, evidence demonstrates that CVR should be replaced by a combination of a resistance-area product (RAP) with a critical closing pressure (CrCP) parameter, the blood pressure value where CBFV reaches zero due to vessels collapsing. Transfer function analysis of the MAP-CBFV relationship can be extended to the MAP-RAP and MAP-CrCP relationships, to assess their contribution to the dynamic CA response. During normocapnia, both RAP and CrCP make a significant contribution to explaining the MAP-CBFV relationship. Hypercapnia, a surrogate state of depressed CA, leads to marked changes in dynamic CA, that are entirely explained by the CrCP response, without further contribution from RAP in comparison with normocapnia., Abstract: Dynamic cerebral autoregulation (CA) is manifested by changes in the diameter of intra-cerebral vessels, which control cerebrovascular resistance (CVR). We investigated the contribution of critical closing pressure (CrCP), an important determinant of CVR, to explain the cerebral blood flow (CBF) response to a sudden change in mean arterial blood pressure (MAP). In 76 healthy subjects (age range 21-70 years, 36 women), recordings of MAP (Finometer), CBF velocity (CBFV; transcranial Doppler ultrasound), end-tidal CO 2 (capnography) and heart rate (ECG) were performed for 5 min at rest (normocapnia) and during hypercapnia induced by breathing 5% CO 2 in air. CrCP and the resistance-area product (RAP) were obtained for each cardiac cycle and their dynamic response to a step change in MAP was calculated by means of transfer function analysis. The recovery of the CBFV response, following a step change in MAP, was mainly due to the contribution of RAP during both breathing conditions. However, CrCP made a highly significant contribution during normocapnia (P < 0.0001) and was the sole determinant of changes in the CBFV response, resulting from hypercapnia, which led to a reduction in the autoregulation index from 5.70 ± 1.58 (normocapnia) to 4.14 ± 2.05 (hypercapnia; P < 0.0001). In conclusion, CrCP makes a very significant contribution to the dynamic CBFV response to changes in MAP and plays a major role in explaining the deterioration of dynamic CA induced by hypercapnia. Further studies are needed to assess the relevance of CrCP contribution in physiological and clinical studies., (© 2020 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Anthropogenic global surface warming is proportional to cumulative carbon emissions 1-3 ; this relationship is partly determined by the uptake and storage of heat and carbon by the ocean 4 . The rates and patterns of ocean heat and carbon storage are influenced by ocean transport, such as mixing and large-scale circulation 5-10 . However, existing climate models do not accurately capture the observed patterns of ocean warming, with a large spread in their projections of ocean circulation and ocean heat uptake 8,11 . Additionally, assessing the influence of ocean circulation changes (specifically, the redistribution of heat by resolved advection) on patterns of observed and simulated ocean warming remains a challenge. Here we establish a linear relationship between the heat and carbon uptake of the ocean in response to anthropogenic emissions. This relationship is determined mainly by intrinsic parameters of the Earth system-namely, the ocean carbon buffer capacity, the radiative forcing of carbon dioxide and the carbon inventory of the ocean. We use this relationship to reveal the effect of changes in ocean circulation from carbon dioxide forcing on patterns of ocean warming in both observations and global Earth system models from the Fifth Coupled Model Intercomparison Project (CMIP5). We show that historical patterns of ocean warming are shaped by ocean heat redistribution, which CMIP5 models simulate poorly. However, we find that projected patterns of heat storage are primarily dictated by the pre-industrial ocean circulation (and small changes in unresolved ocean processes)-that is, by the patterns of added heat owing to ocean uptake of excess atmospheric heat rather than ocean warming by circulation changes. Climate models show more skill in simulating ocean heat storage by the pre-industrial circulation compared to heat redistribution, indicating that warming patterns of the ocean may become more predictable as the climate warms.

Thousands of clinical trials are conducted globally each year. Yet, little is known about their environmental impact. This paper presents the results of a high-level literature review of the carbon footprint of clinical trials. Five papers were identified and their contents summarised qualitatively. All papers were authored by UK researchers. Carbon footprint metrics from 14 trials were presented in carbon dioxide equivalents (CO2e). Emissions were broken down by three broadly defined clinical trial activities: operations, travel, and supplies. Recommen - dations for carbon reduction are discussed. The review showed a dearth of publications on greenhouse gas emissions generated by clinical trials. More work in this area is needed to achieve sustainable, low carbon clinical research. [ABSTRACT FROM AUTHOR]

Atmospheric carbon dioxide enrichment (eCO 2 ) can enhance plant carbon uptake and growth 1-5 , thereby providing an important negative feedback to climate change by slowing the rate of increase of the atmospheric CO 2 concentration 6 . Although evidence gathered from young aggrading forests has generally indicated a strong CO 2 fertilization effect on biomass growth 3-5 , it is unclear whether mature forests respond to eCO 2 in a similar way. In mature trees and forest stands 7-10 , photosynthetic uptake has been found to increase under eCO 2 without any apparent accompanying growth response, leaving the fate of additional carbon fixed under eCO 2 unclear 4,5,7-11 . Here using data from the first ecosystem-scale Free-Air CO 2 Enrichment (FACE) experiment in a mature forest, we constructed a comprehensive ecosystem carbon budget to track the fate of carbon as the forest responded to four years of eCO 2 exposure. We show that, although the eCO 2 treatment of +150 parts per million (+38 per cent) above ambient levels induced a 12 per cent (+247 grams of carbon per square metre per year) increase in carbon uptake through gross primary production, this additional carbon uptake did not lead to increased carbon sequestration at the ecosystem level. Instead, the majority of the extra carbon was emitted back into the atmosphere via several respiratory fluxes, with increased soil respiration alone accounting for half of the total uptake surplus. Our results call into question the predominant thinking that the capacity of forests to act as carbon sinks will be generally enhanced under eCO 2 , and challenge the efficacy of climate mitigation strategies that rely on ubiquitous CO 2 fertilization as a driver of increased carbon sinks in global forests.

The ratio of leaf internal (c i ) to ambient (c a ) partial pressure of CO 2 , defined here as χ, is an index of adjustments in both leaf stomatal conductance and photosynthetic rate to environmental conditions. Measurements and proxies of this ratio can be used to constrain vegetation model uncertainties for predicting terrestrial carbon uptake and water use. We test a theory based on the least-cost optimality hypothesis for modelling historical changes in χ over the 1951-2014 period, across different tree species and environmental conditions, as reconstructed from stable carbon isotopic measurements across a global network of 103 absolutely dated tree-ring chronologies. The theory predicts optimal χ as a function of air temperature, vapour pressure deficit, c a and atmospheric pressure. The theoretical model predicts 39% of the variance in χ values across sites and years, but underestimates the intersite variability in the reconstructed χ trends, resulting in only 8% of the variance in χ trends across years explained by the model. Overall, our results support theoretical predictions that variations in χ are tightly regulated by the four environmental drivers. They also suggest that explicitly accounting for the effects of plant-available soil water and other site-specific characteristics might improve the predictions., (© 2019 The Authors. New Phytologist © 2019 New Phytologist Trust.)

Structurally intact tropical forests sequestered about half of the global terrestrial carbon uptake over the 1990s and early 2000s, removing about 15 per cent of anthropogenic carbon dioxide emissions 1-3 . Climate-driven vegetation models typically predict that this tropical forest 'carbon sink' will continue for decades 4,5 . Here we assess trends in the carbon sink using 244 structurally intact African tropical forests spanning 11 countries, compare them with 321 published plots from Amazonia and investigate the underlying drivers of the trends. The carbon sink in live aboveground biomass in intact African tropical forests has been stable for the three decades to 2015, at 0.66 tonnes of carbon per hectare per year (95 per cent confidence interval 0.53-0.79), in contrast to the long-term decline in Amazonian forests 6 . Therefore the carbon sink responses of Earth's two largest expanses of tropical forest have diverged. The difference is largely driven by carbon losses from tree mortality, with no detectable multi-decadal trend in Africa and a long-term increase in Amazonia. Both continents show increasing tree growth, consistent with the expected net effect of rising atmospheric carbon dioxide and air temperature 7-9 . Despite the past stability of the African carbon sink, our most intensively monitored plots suggest a post-2010 increase in carbon losses, delayed compared to Amazonia, indicating asynchronous carbon sink saturation on the two continents. A statistical model including carbon dioxide, temperature, drought and forest dynamics accounts for the observed trends and indicates a long-term future decline in the African sink, whereas the Amazonian sink continues to weaken rapidly. Overall, the uptake of carbon into Earth's intact tropical forests peaked in the 1990s. Given that the global terrestrial carbon sink is increasing in size, independent observations indicating greater recent carbon uptake into the Northern Hemisphere landmass 10 reinforce our conclusion that the intact tropical forest carbon sink has already peaked. This saturation and ongoing decline of the tropical forest carbon sink has consequences for policies intended to stabilize Earth's climate.

Net anthropogenic emissions of carbon dioxide (CO 2 ) must approach zero by mid-century (2050) in order to stabilize the global mean temperature at the level targeted by international efforts 1-5 . Yet continued expansion of fossil-fuel-burning energy infrastructure implies already 'committed' future CO 2 emissions 6-13 . Here we use detailed datasets of existing fossil-fuel energy infrastructure in 2018 to estimate regional and sectoral patterns of committed CO 2 emissions, the sensitivity of such emissions to assumed operating lifetimes and schedules, and the economic value of the associated infrastructure. We estimate that, if operated as historically, existing infrastructure will cumulatively emit about 658 gigatonnes of CO 2 (with a range of 226 to 1,479 gigatonnes CO 2 , depending on the lifetimes and utilization rates assumed). More than half of these emissions are predicted to come from the electricity sector; infrastructure in China, the USA and the 28 member states of the European Union represents approximately 41 per cent, 9 per cent and 7 per cent of the total, respectively. If built, proposed power plants (planned, permitted or under construction) would emit roughly an extra 188 (range 37-427) gigatonnes CO 2 . Committed emissions from existing and proposed energy infrastructure (about 846 gigatonnes CO 2 ) thus represent more than the entire carbon budget that remains if mean warming is to be limited to 1.5 degrees Celsius (°C) with a probability of 66 to 50 per cent (420-580 gigatonnes CO 2 ) 5 , and perhaps two-thirds of the remaining carbon budget if mean warming is to be limited to less than 2 °C (1,170-1,500 gigatonnes CO 2 ) 5 . The remaining carbon budget estimates are varied and nuanced 14,15 , and depend on the climate target and the availability of large-scale negative emissions 16 . Nevertheless, our estimates suggest that little or no new CO 2 -emitting infrastructure can be commissioned, and that existing infrastructure may need to be retired early (or be retrofitted with carbon capture and storage technology) in order to meet the Paris Agreement climate goals 17 . Given the asset value per tonne of committed emissions, we suggest that the most cost-effective premature infrastructure retirements will be in the electricity and industry sectors, if non-emitting alternatives are available and affordable 4,18 .

The article focuses on plastic is ubiquitous in people's lives, when plastic-containing items have fulfilled their missions, only a small amount is recycled into new products, which are often of lower quality, compared with the original material. Topics include the waste into high-value chemicals requires substantial energy, the researchers have combined a ruthenium-carbon catalyst, and the lower-energy reaction conditions to convert plastics used in bottles and other packaging into fuels.

• Nanogel particles for CO 2 capture with lower cycles (303–348 K) are developed. • Carbon paper as supporter shows higher CO 2 capacity, adsorption and desorption rate. • Avrami's fractional order model accurately predicts the CO 2 uptake behaviors. • The CO 2 capture process is governed by film and intraparticle diffusion resistance. • Carbon paper as supporter shows lower sensible heat and desorption activation energy. Amine-containing nanogel particles with a lower cooling and heating cycles (303–348 K), which is beneficial to limit the degradation and volatile of amine, has been developed as promising absorbents for CO 2 capture. It is extremely important to understand the CO 2 capture kinetics and mechanisms for design and operation of corresponding processes. In present work, poly tetra fluoroethylene and carbon paper were used to support the GPs by filtering and loading method. The CO 2 uptake and release performance of poly tetra fluoroethylene and carbon paper supported nanogel particles was measured. It was found that carbon paper as supporter shows higher CO 2 capacity and desorption rate. A comparison of three different kinetic models shows that carbon paper as supporter gives a more enhanced kinetic behavior. Avrami's fractional order model presents the best fit to experimental data. To further investigate the mechanism of CO 2 uptake on absorbents, interparticle diffusion model, intraparticle diffusion model and Boyd's film diffusion model were also applied. Film diffusion resistance governed the mass transfer rate of CO 2 uptake on studied absorbents at the initial CO 2 uptake stages. In the following stages, intra-particle diffusion resistance plays a major role until the equilibrium is reached. The sensible heat of carbon paper as supporter is about 25% lower than that of poly tetra fluoroethylene as supporter. The desorption activation energy obtained from the Arrhenius equation is 18 kJ/mol for carbon paper as supporter, which is 84% lower than that of the typical aqueous MEA solvent. [ABSTRACT FROM AUTHOR]

The papers by Yang et al. [[5]] and Wang et al. [[6]] mainly studied the corrosion of CO SB 2 sb on gathering pipelines and the monitoring of the corrosion rate. The paper by Hou et al. [[1]] investigated the microscopic adsorption pattern of CH SB 4 sb and the competitive adsorption behavior of CH SB 4 sb and CO SB 2 sb in sodium-based montmorillonite using molecular simulation methods. The CO SB 2 sb pre-pad energized fracturing technology can not only further increase oil production, but also effectively realize the geological storage and utilization of CO SB 2 sb , thus greatly reducing the greenhouse effect. [Extracted from the article]

This comment addresses several points regarding data interpretation in a recent paper in the Journal, which results in an inaccurate interpretation of experimental data on CO 2 diffusion in water. The experimental data were interpreted by Fick's law of diffusion, while the existence of convection was disregarded. [ABSTRACT FROM AUTHOR]