XCO

Greenhouse gas satellites can provide consistently global CO2 data which are important inputs for the top-down inverse estimation of CO2 emissions and their dynamic changes. By tracking greenhouse gas emissions, policymakers and businesses can identify areas where reductions are needed most and implement effective strategies to reduce their impact on the environment. Monitoring greenhouse gases provides valuable data for scientists studying climate change. The requirements for CO2 emissions monitoring and verification support capacity drive the payload design of future CO2 satellites...

CO2 emissions from power plants are the dominant source of global CO2 emissions, thus in the context of global warming, accurate estimation of CO2 emissions from power plants is essential for the effective control of carbon emissions. Based on the XCO2 retrievals from the Orbiting Carbon Observatory 2 (OCO-2) and the Gaussian Plume Model (GPM), a series of studies have been carried out to estimate CO2 emission from power plants. However, the GPM is an ideal model, and there are a number of assumptions that need to be made when using this model, resulting in large uncertainties in the inverted emissions...

Switching the reaction routes in peroxymonosulfate (PMS)-based advanced oxidation processes have attracted much attention but remain challenging. Herein, a series of Co-N/C catalysts with different compositions and structures were prepared by using bimetallic zeolitic imidazolate frameworks based on ZIF-8 and ZIF-67 (xZn/Co-ZIFs). Results show that Co doping amount could mediate the transformation of the activation pathway of PMS over Co-N/C. When Co doping amount was less than 10%, the constructed xCo-N/C/PMS system (x ≤ 10%) was singlet oxygen-dominated reaction; however further increasing Co doping amount would lead to the generation and coexistence of sulfate radicals and high-valent cobalt, besides singlet oxygen...

OBJECTIVES: This study aimed to explore the risk factors of hypoglycemia in patients with gastrointestinal bleeding caused by somatostatin for injection and to establish a prediction model based on logistic regression combined with receiver operating characteristic (ROC) curve. MATERIALS AND METHODS: This retrospective study analyzed patients diagnosed with gastrointestinal bleeding and treated with somatostatin from January 2022 to May 2023 and collected hypoglycemic events...

The spatiotemporal evolution patterns of carbon emissions and their influence mechanisms are important topics for regional climate change monitoring and research on sustainable development goals. At present, due to the limitation of statistical data collection scale, it is difficult to analyze the spatiotemporal variation of carbon emission and its influence mechanism at a finer scale in China. With the development of new remote sensing platforms and technologies, multisource remote sensing data such as nighttime light remote sensing data and XCO2 concentration data have become important information resources for carbon emission monitoring...

To our knowledge, no study has investigated the reliability of the time to exhaustion (TTE) test during constant-load trials in Olympic distance cross-country mountain bike (XCO-MTB) athletes. Thus, the aim was to analyze the reliability of the TTE test at intensities above peak oxygen uptake (VO2peak ) in trained XCO-MTB athletes. Fifteen male XCO-MTB athletes (mean ± SD: age 31.5 ± 6.6 years, stature 174.0 ± 5.4 cm, body mass 67.2 ± 5.1 kg, VO2peak 64.5 ± 4.7 mL·kg-1 ·min-1 ) completed 2 TTE tests on the cycle ergometer with 4 different intensities above the maximal work rate in the incremental test (Wmax ) (105%, 120%, 130%, and 140% of Wmax )...

Long-time-series, high-resolution datasets of the column-averaged dry-air mole fraction of carbon dioxide (XCO2 ) have great practical importance for mitigating the greenhouse effect, assessing carbon emissions and implementing a low-carbon cycle. However, the mainstream XCO2 datasets obtained from satellite observations have coarse spatial resolutions and are inadequate for supporting research applications with different precision requirements. Here, we developed a new spatial machine learning model by fusing spatial information with CatBoost, called SCatBoost, to fill the above gap based on existing global land-mapped 1° XCO2 data (GLM-XCO2 )...

India is primarily concerned with comprehending regional carbon source-sink response in the context of changes in atmospheric CO2 concentrations or anthropogenic emissions. Recent advancements in high-resolution satellite's fine-scale XCO2 measurements provide an opportunity to understand unprecedented details of source-sink activity on a regional scale. In this study, we investigated the long-term variations of XCO2 concentration and growth rates as well as its covarying relationship with ENSO and regional climate parameters (temperature, precipitation, soil moisture, and NDVI) over India from 2010 to 2021 using GOSAT and OCO-2 retrievals...

China has set a goal to achieve carbon neutrality by 2060, and satellite remote sensing allows for acquiring large-range and high-resolution carbon dioxide (CO2 ) data, which can aid in achieving this goal. However, satellite-derived column-averaged dry-air mole fraction of CO2 (XCO2 ) products often suffer from substantial spatial gaps due to the impacts of narrow swath and clouds. Here, this paper generates daily full-coverage XCO2 data at a high spatial resolution of 0.1° over China during 2015-2020, by fusing satellite observations and reanalysis data in a deep neural network (DNN) framework...

Combining with Carbon dioxide column concentration (XCO2) remote sensing data, it is of great scientific significance to obtain XCO2 long time series data with high precision and high spatio-temporal coverage. In this study, the combination framework of DINEOF and BME were employed to integrate the XCO2 data of GOSAT, OCO-2 and OCO-3 satellites for generating global XCO2 data from January 2010 to December 2020, with the average monthly space coverage rate of more than 96 %. Through cross-validation and comparison of The Total Carbon Column Observing Network (TCCON) XCO2 data and DINEOF-BME interpolation XCO2 products, it is verified that DINEOF-BME method has better interpolation accuracy, and the coefficient of determination of interpolated XCO2 products and TCCON data is 0...

Variations in atmosphere total column-mean CO2 (XCO2 ) collected by the National Aeronautics and Space Administration's Orbiting Carbon Observatory-2 satellite can be used to constrain surface carbon fluxes if the influence of atmospheric transport and observation errors on the data is known and accounted for. Due to sparse validation data, the portions of fine-scale variability in XCO2 driven by fluxes, transport, or retrieval errors remain uncertain, particularly over the ocean. To better understand these drivers, we characterize variability in OCO-2 Level 2 version 10 XCO2 from the seasonal scale, synoptic-scale (order of days, thousands of kilometers), and mesoscale (within-day, hundreds of kilometers) for 10 biomes over North America and adjacent ocean basins...

High CO concentration and dense aerosol layers at 1-6 km altitude in the free troposphere were observed over Rikubetsu, Japan, in ground-based Fourier transform spectrometer (FTS) and lidar measurements during 18-20 May 2016, days after intense wildfires east of Lake Baikal, Siberia. The column-averaged dry-air mole fraction of CO (XCO) was observed to be ∼150 ppb from 11:15 to 13:50 JST on 19 May, and peak aerosol optical depths (AODs) of 1.41 and 1.28 were observed at 15:40 JST 18 May and 11:20 JST 19 May, respectively...

Frontal boundaries have been shown to cause large changes in CO2 mole-fractions, but clouds and the complex vertical structure of fronts make these gradients difficult to observe. It remains unclear how the column average CO2 dry air mole-fraction (XCO2 ) changes spatially across fronts, and how well airborne lidar observations, data assimilation systems, and numerical models without assimilation capture XCO2 frontal contrasts (ΔXCO2, i.e., warm minus cold sector average of XCO2 ). We demonstrated the potential of airborne Multifunctional Fiber Laser Lidar (MFLL) measurements in heterogeneous weather conditions (i...

The cryptomelane-type manganese oxide (OMS-2)-supported Co (xCo/OMS-2; x = 5, 10, and 15 wt.%) catalysts were prepared via a pre-incorporation route. The as-prepared materials were used as catalysts for catalytic oxidation of toluene (2000 ppmV). Physical and chemical properties of the catalysts were measured using the X-ray diffraction (XRD), Fourier transform infrared spectroscopic (FT-IR), scanning electron microscopic (SEM), X-ray photoelectron spectroscopy (XPS), and hydrogen temperature-programmed reduction (H2 -TPR) techniques...

As China is the world's largest CO2 emitter, it is important to understand the spatio-temporal variation of atmospheric CO2 to reduce carbon emissions. Satellite remote sensing for carbon monitoring has been widely used and studied because of its long-term and large-scale characteristics. However, the satellite data results are very sparse with significant gaps due to narrow swath and other factors on CO2 retrieval. The simple interpolation methods ignore the influential factors of CO2 and loss the spatial resolution, which leads to the inability to quantify the spatio-temporal variation well...

The first aim of the present study was to assess the dietary intake of professional cyclists during pre-season. The second aim was to assess the dietary habits of this population during a complete season. Fifteen elite male (age: 23.2 ± 5.4 years) and twenty-three elite female (age: 20.1 ± 7.0 years) cyclists volunteered to participate in the study. Dietary nutrient intake during pre-season was assessed using a 72 h dietary recall interview, and a 136-item food frequency questionnaire was used to assess dietary habits during the year...

The extreme climate caused by global warming has had a great impact on the earth's ecology. As the main greenhouse gas, atmospheric CO2 concentration change and its spatial distribution are among the main uncertain factors in climate change assessment. Remote sensing satellites can obtain changes in CO2 concentration in the global atmosphere. However, some problems (e.g., low time resolution and incomplete coverage) caused by the satellite observation mode and clouds/aerosols still exist. By analyzing sources of atmospheric CO2 and various factors affecting the spatial distribution of CO2 , this study used multisource satellite-based data and a random forest model to reconstruct the daily CO2 column concentration (XCO2 ) with full spatial coverage in the Beijing-Tianjin-Hebei region...

Exploring the spatial distribution of the multi-fractal scaling behaviours in atmospheric CO2 concentration time series is useful for understanding the dynamic mechanisms of carbon emission and absorption. In this work, we utilise a well-established multi-fractal detrended fluctuation analysis to examine the multi-fractal scaling behaviour of a column-averaged dry-air mole fraction of carbon dioxide (XCO2 ) concentration time series over China, and portray the spatial distribution of the multi-fractal scaling behaviour...

Commercialized lithium cobalt oxide (LCO) only shows a relatively low capacity of ≈175 mAh g-1 despite a high theoretical capacity of ≈274 mAh g-1 . As an effective and direct strategy, increasing its charge cutoff voltage can, in principle, escalate the capacity, which is however precluded by the irreversible phase transition, oxygen loss, and severe side reactions with electrolytes normally. Herein, an in situ sulfur-assisted solid-state approach is proposed for one-pot synthesis of long-term highly stable high-voltage LCO with a novel compound structure...

Measurements of column-averaged dry-air mole fractions of carbon dioxide and carbon monoxide, CO2 (XCO2 ) and CO (XCO), were performed throughout 2019 at an urban site in Beijing using a compact Fourier Transform Spectrometer (FTS) EM27/SUN. This data set is used to assess the characteristics of combustion-related CO2 emissions of urban Beijing by analyzing the correlated daily anomalies of XCO and XCO2 (e.g., ΔXCO and ΔXCO2 ). The EM27/SUN measurements were calibrated to a 125HR-FTS at the Xianghe station by an extra EM27/SUN instrument transferred between two sites...