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ClF is alpha carbon monoxide-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four chlorine fluoride molecules. Cl is bonded in a single-bond geometry to one F atom. The Cl–F bond length is 1.69 Å. F is bonded in a single-bond geometry to one Cl atom.
NO is alpha carbon monoxide-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four nitroxyl molecules. N is bonded in a single-bond geometry to one O atom. The N–O bond length is 1.17 Å. O is bonded in a single-bond geometry to one N atom.
HBr is alpha carbon monoxide structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four hydrobromic acid molecules. H1+ is bonded in a single-bond geometry to one Br1- atom. The H–Br bond length is 1.44 Å. Br1- is bonded in a single-bond geometry to one H1+ atom.
HBr is alpha carbon monoxide-like structured and crystallizes in the orthorhombic Cmc2_1 space group. The structure is zero-dimensional and consists of four hydrobromic acid molecules. H1+ is bonded in a single-bond geometry to one Br1- atom. The H–Br bond length is 1.47 Å. Br1- is bonded in a single-bond geometry to one H1+ atom.
HF is alpha carbon monoxide-like structured and crystallizes in the orthorhombic Cmc2_1 space group. The structure is zero-dimensional and consists of four hydrofluoric acid molecules. H1+ is bonded in a single-bond geometry to one F1- atom. The H–F bond length is 0.95 Å. F1- is bonded in a single-bond geometry to one H1+ atom.
HCl is alpha carbon monoxide-like structured and crystallizes in the orthorhombic Cmc2_1 space group. The structure is zero-dimensional and consists of four hydrochloric acid molecules. H1+ is bonded in a single-bond geometry to one Cl1- atom. The H–Cl bond length is 1.30 Å. Cl1- is bonded in a single-bond geometry to one H1+ atom.
AsN9 is Theoretical Carbon Structure-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four AsN9 clusters. As5+ is bonded in a distorted T-shaped geometry to three N+0.56- atoms. There are a spread of As–N bond distances ranging from 1.94–1.96 Å. There are nine inequivalent N+0.56- sites. In the first N+0.56- site, N+0.56- is bonded in a bent 120 degrees geometry to one As5+ and one N+0.56- atom. The N–N bond length is 1.23 Å. In the second N+0.56- site, N+0.56- is bonded in a single-bond geometry to one N+0.56- atom. The N–N bond length is 1.15 Å. In the third N+0.56- site, N+0.56- is bonded in a linear geometry to two N+0.56- atoms. The N–N bond length is 1.15 Å. In the fourth N+0.56- site, N+0.56- is bonded in a single-bond geometry to one N+0.56- atom. The N–N bond length is 1.15 Å. In the fifth N+0.56- site, N+0.56- is bonded in a single-bond geometry to one N+0.56- atom. In the sixth N+0.56- site, N+0.56- is bonded in a distorted bent 120 degrees geometry to one As5+ and one N+0.56- atom. The N–N bond length is 1.23 Å. In the seventh N+0.56- site, N+0.56- is bonded in a linear geometry to two N+0.56- atoms. The N–N bond length is 1.23 Å. In the eighth N+0.56- site, N+0.56- is bonded in a distorted bent 120 degrees geometry to one As5+ and one N+0.56- atom. In the ninth N+0.56- site, N+0.56- is bonded in a linear geometry to two N+0.56- atoms.
BrCl is alpha carbon monoxide-like structured and crystallizes in the hexagonal P6_3mc space group. The structure is zero-dimensional and consists of two bromine chloride molecules. Br is bonded in a single-bond geometry to one Cl atom. The Br–Cl bond length is 2.17 Å. Cl is bonded in a single-bond geometry to one Br atom.
LiSi3H27(C3O)3Si is alpha carbon monoxide-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four silicon molecules and four LiSi3H27(C3O)3 clusters. In each LiSi3H27(C3O)3 cluster, Li1+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.99 Å) and two longer (2.00 Å) Li–O bond length. There are three inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded in a trigonal non-coplanar geometry to two C4- and one O2- atom. Both Si–C bond lengths are 1.89 Å. The Si–O bond length is 1.73 Å. In the second Si4+ site, Si4+ is bonded in a trigonal non-coplanar geometry to two C4- and one O2- atom. Both Si–C bond lengths are 1.89 Å. The Si–O bond length is 1.73 Å. In the third Si4+ site, Si4+ is bonded in a trigonal non-coplanar geometry to two C4- and one O2- atom. Both Si–C bond lengths are 1.89 Å. The Si–O bond length is 1.73 Å. There are nine inequivalent C4- sites. In the first C4- site, C4- is bonded in a tetrahedral geometry to three H+0.93+ and one O2- atom. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.44 Å. In the second C4- site, C4- is bonded in a tetrahedral geometry to three H+0.93+ and one O2- atom. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.44 Å. In the third C4- site, C4- is bonded in a tetrahedral geometry to three H+0.93+ and one O2- atom. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.43 Å. In the fourth C4- site, C4- is bonded to one Si4+ and three H+0.93+ atoms to form corner-sharing CSiH3 tetrahedra. All C–H bond lengths are 1.10 Å. In the fifth C4- site, C4- is bonded to one Si4+ and three H+0.93+ atoms to form corner-sharing CSiH3 tetrahedra. All C–H bond lengths are 1.10 Å. In the sixth C4- site, C4- is bonded to one Si4+ and three H+0.93+ atoms to form corner-sharing CSiH3 tetrahedra. All C–H bond lengths are 1.10 Å. In the seventh C4- site, C4- is bonded to one Si4+ and three H+0.93+ atoms to form corner-sharing CSiH3 tetrahedra. All C–H bond lengths are 1.10 Å. In the eighth C4- site, C4- is bonded to one Si4+ and three H+0.93+ atoms to form corner-sharing CSiH3 tetrahedra. All C–H bond lengths are 1.10 Å. In the ninth C4- site, C4- is bonded to one Si4+ and three H+0.93+ atoms to form corner-sharing CSiH3 tetrahedra. All C–H bond lengths are 1.10 Å. There are twenty-seven inequivalent H+0.93+ sites. In the first H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the second H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the third H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the fourth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the fifth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the sixth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the seventh H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the eighth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the ninth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the tenth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the eleventh H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the twelfth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the thirteenth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the fourteenth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the fifteenth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the sixteenth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the seventeenth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the eighteenth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the nineteenth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the twentieth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the twenty-first H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the twenty-second H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the twenty-third H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the twenty-fourth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the twenty-fifth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the twenty-sixth H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. In the twenty-seventh H+0.93+ site, H+0.93+ is bonded in a single-bond geometry to one C4- atom. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to one Li1+, one Si4+, and one C4- atom. In the second O2- site, O2- is bonded in a trigonal planar geometry to one Li1+, one Si4+, and one C4- atom. In the third O2- site, O2- is bonded in a trigonal planar geometry to one Li1+, one Si4+, and one C4- atom.
TcB is alpha carbon monoxide-like structured and crystallizes in the hexagonal P6_3mc space group. The structure is zero-dimensional and consists of two TcB clusters. Tc3- is bonded in a single-bond geometry to one B3+ atom. The Tc–B bond length is 1.77 Å. B3+ is bonded in a single-bond geometry to one Tc3- atom.
O2(BrO)2 is alpha carbon monoxide-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two hydrogen peroxide molecules and four hypobromous acid molecules.
ClO is alpha carbon monoxide-like structured and crystallizes in the tetragonal I4_1/amd space group. The structure is zero-dimensional and consists of eight chlorine molecules and eight hydrogen peroxide molecules.
The exhaust plume capture method is a commonly used approach to measure pollutants emitted by in-use heavy-duty diesel trucks. Lower cost sensors, if used in place of traditional research-grade analyzers, could enable wider application of this method, including use as a monitoring tool to identify high-emitting trucks that may warrant inspection and maintenance. However, low-cost sensors have for the most part only been evaluated under ambient conditions as opposed to source-influenced environments with rapidly changing pollutant concentrations. This study compared black carbon (BC) emission factors determined using different BC and carbon dioxide (CO 2 ) sensors that range in cost from $200 to $20,000. Controlled laboratory experiments show that traditional zero and span steady-state calibration checks are not robust indicators of sensor performance when sampling short duration concentration peaks. Fleet BC emission factor distributions measured at two locations at the Port of Oakland in California with 16 BC/CO 2 sensor pairs were similar, but unique sensor pairs identified different high-emitting trucks. At one location, the low-cost PP Systems SBA-5 agreed on the classification of 90% of the high emitters identified by the LI-COR LI-7000 when both were paired with the Magee Scientific AE33. Conversely, lower cost BC sensors when paired with the LI-7000 misclassified more than 50% of high emitters when compared to the AE33/LI-7000. Confidence in emission factor quantification and high-emitter identification improves with larger integrated peak areas of CO 2 and especially BC. This work highlights that sensor evaluation should be conducted under application-specific conditions, whether that be for ambient air monitoring or source characterization.
Abstract. Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere in a changing climate is critical to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe and synthesize datasets and methodologies to quantify the five major components of the global carbon budget and their uncertainties. Fossil CO2 emissions (EFOS) are based on energy statistics and cement production data, while emissions from land-use change (ELUC) are based on land-use and land-use change data and bookkeeping models. Atmospheric CO2 concentration is measured directly, and its growth rate (GATM) is computed from the annual changes in concentration. The global net uptake of CO2 by the ocean (SOCEAN, called the ocean sink) is estimated with global ocean biogeochemistry models and observation-based fCO2 products (fCO2 is the fugacity of CO2). The global net uptake of CO2 by the land (SLAND, called the land sink) is estimated with dynamic global vegetation models. Additional lines of evidence on land and ocean sinks are provided by atmospheric inversions, atmospheric oxygen measurements, and Earth system models. The sum of all sources and sinks results in the carbon budget imbalance (BIM), a measure of imperfect data and incomplete understanding of the contemporary carbon cycle. All uncertainties are reported as ±1σ. For the year 2023, EFOS increased by 1.3 % relative to 2022, with fossil emissions at 10.1 ± 0.5 GtC yr−1 (10.3 ± 0.5 GtC yr−1 when the cement carbonation sink is not included), and ELUC was 1.0 ± 0.7 GtC yr−1, for a total anthropogenic CO2 emission (including the cement carbonation sink) of 11.1 ± 0.9 GtC yr−1 (40.6 ± 3.2 GtCO2 yr−1). Also, for 2023, GATM was 5.9 ± 0.2 GtC yr−1 (2.79 ± 0.1 ppm yr−1; ppm denotes parts per million), SOCEAN was 2.9 ± 0.4 GtC yr−1, and SLAND was 2.3 ± 1.0 GtC yr−1, with a near-zero BIM (−0.02 GtC yr−1). The global atmospheric CO2 concentration averaged over 2023 reached 419.31 ± 0.1 ppm. Preliminary data for 2024 suggest an increase in EFOS relative to 2023 of +0.8 % (−0.2 % to 1.7 %) globally and an atmospheric CO2 concentration increase by 2.87 ppm, reaching 422.45 ppm, 52 % above the pre-industrial level (around 278 ppm in 1750). Overall, the mean of and trend in the components of the global carbon budget are consistently estimated over the period 1959–2023, with a near-zero overall budget imbalance, although discrepancies of up to around 1 GtC yr−1 persist for the representation of annual to semi-decadal variability in CO2 fluxes. Comparison of estimates from multiple approaches and observations shows the following: (1) a persistent large uncertainty in the estimate of land-use change emissions, (2) low agreement between the different methods on the magnitude of the land CO2 flux in the northern extra-tropics, and (3) a discrepancy between the different methods on the mean ocean sink. This living-data update documents changes in methods and datasets applied to this most recent global carbon budget as well as evolving community understanding of the global carbon cycle. The data presented in this work are available at https://doi.org/10.18160/GCP-2024 (Friedlingstein et al., 2024).
Abstract. Previous phases of the Coupled Model Intercomparison Project (CMIP) have primarily focused on simulations driven by atmospheric concentrations of greenhouse gases (GHGs), for both idealized model experiments and climate projections of different emissions scenarios. We argue that although this approach was practical to allow parallel development of Earth system model simulations and detailed socioeconomic futures, carbon cycle uncertainty as represented by diverse, process-resolving Earth system models (ESMs) is not manifested in the scenario outcomes, thus omitting a dominant source of uncertainty in meeting the Paris Agreement. Mitigation policy is defined in terms of human activity (including emissions), with strategies varying in their timing of net-zero emissions, the balance of mitigation effort between short-lived and long-lived climate forcers, their reliance on land use strategy, and the extent and timing of carbon removals. To explore the response to these drivers, ESMs need to explicitly represent complete cycles of major GHGs, including natural processes and anthropogenic influences. Carbon removal and sequestration strategies, which rely on proposed human management of natural systems, are currently calculated in integrated assessment models (IAMs) during scenario development with only the net carbon emissions passed to the ESM. However, proper accounting of the coupled system impacts of and feedback on such interventions requires explicit process representation in ESMs to build self-consistent physical representations of their potential effectiveness and risks under climate change. We propose that CMIP7 efforts prioritize simulations driven by CO2 emissions from fossil fuel use and projected deployment of carbon dioxide removal technologies, as well as land use and management, using the process resolution allowed by state-of-the-art ESMs to resolve carbon–climate feedbacks. Post-CMIP7 ambitions should aim to incorporate modeling of non-CO2 GHGs (in particular, sources and sinks of methane and nitrous oxide) and process-based representation of carbon removal options. These developments will allow three primary benefits: (1) resources to be allocated to policy-relevant climate projections and better real-time information related to the detectability and verification of emissions reductions and their relationship to expected near-term climate impacts, (2) scenario modeling of the range of possible future climate states including Earth system processes and feedbacks that are increasingly well-represented in ESMs, and (3) optimal utilization of the strengths of ESMs in the wider context of climate modeling infrastructure (which includes simple climate models, machine learning approaches and kilometer-scale climate models).
Abstract Hydrogen, as an important clean energy source, plays a more and more crucial role in decarbonizing the planet and meeting the global climate challenge due to its high energy density and zero‐emission. The demand for sustainable hydrogen is increasing drastically worldwide as driven by the global shift towards low‐carbon energy solutions. Thermochemical catalysis process dominates hydrogen production at scale given its relatively mature technology and commercialization status, as well as the established manufacturing infrastructure. While due to its environmentally friendly nature and growing abundant sources of renewable electricity, the electrochemical path for hydrogen production is rising as a major alternative to the thermochemical means. Nevertheless, hierarchically structured catalysts and devices have gradually taken the center stage toward replacing the traditional counterparts, especially with the rapid advancement of the design and manufacture of such ordered nanostructure assemblies toward high activity, efficient mass transport, and superb stability. In this review, the latest progress of the hierarchically structured catalysts for hydrogen production have been surveyed on electro‐ and thermo‐ chemical pathways comparatively. It covers the structure designs of atomic dispersion, nanoscale surfaces and interfaces for achieving highly active and durable catalysts, components, and devices. Both electrochemical and thermochemical approaches are reviewed in terms of the vast design details, engineered benefits, and understandings of various Pt‐group metal (PGM) and non‐PGM based transition metal catalysts for hydrogen production. As the growing trend, brief discussions are also presented toward the high‐level assembly and manufacture of complexly structured components and devices at scale in the electrochemical and thermochemical energy systems.
Al(H2)6 is alpha carbon monoxide-like structured and crystallizes in the cubic Fd-3m space group. The structure is zero-dimensional and consists of eight aluminum molecules and forty-eight hydrogen molecules.
The 2022 IPCC Sixth Assessment Report tells a worrying tale of global warming that temperatures will exceed beyond a 1.5 °C increase in the near future. Higher global temperatures result in more frequent and extreme weather events, irreversible ecosystem changes, and will contribute to detrimental impacts on human health. Anthropogenic greenhouse gas emissions— including those from burning fossil fuels for energy use—are the primary drivers of climate change. Organizations like the U.S Department of Energy’s (DOE) Office of Fossil Energy and Carbon Management (FECM) are working to decrease the environmental impacts of fossil fuels as society works towards net-zero emissions. To complete this goal, society must reduce its dependence on fossil fuels and move towards cleaner energy sources such as biofuels.