Carbon Monoxide Research Articles

Sulfur-doped Bi2O2CO3 nanosheet for enhanced visible-light-driven photocatalytic CO2 reduction to CO with ultra-high selectivity.

The photocatalytic reduction of carbon dioxide (CO2) has emerged as a compelling strategy for the conversion of renewable energy. However, the expeditious recombination of photogenerated charge carriers and the inadequate light absorption capabilities are currently predominant challenges. Herein, we developed a facile hydrothermal approach to synthesize a sulfur doped Bi2O2CO3 nanosheet with a tunable energy band structure designed to enhance visible light absorption. Our findings indicate that the incorporation of sulfur into the catalytic sites induces an electron sink effect, significantly improving the separation efficiency of photogenerated charge carriers. Consequently, this sulfur-doped Bi2O2CO3 catalyst exhibits a remarkable carbon monoxide (CO) yield of 16.64 μmol gcat-1 h-1 with nearly 100 % selectivity under illumination ranging from 420 to 780 nm. Through in-situ characterization techniques and theoretical calculations, it was revealed that sulfur-coordinated bismuth sites greatly enhance CO2 adsorption and decrease the energy barrier for critical intermediates formation (*COOH), thus selectively driving the reaction towards CO production. This work not only advances our understanding of mechanisms underlying photocatalytic reduction of CO2 on sulfur-doped bismuth-based catalysts but also sets a precedent for developing sophisticated photocatalytic systems for enhanced photoreduction reactions.

Anthropic-Induced Variability of Greenhouse Gasses and Aerosols at the WMO/GAW Coastal Site of Lamezia Terme (Calabria, Southern Italy): Towards a New Method to Assess the Weekly Distribution of Gathered Data

The key to a sustainable future is the reduction in humankind’s impact on natural systems via the development of new technologies and the improvement in source apportionment. Although days, years and seasons are arbitrarily set, their mechanisms are based on natural cycles driven by Earth’s orbital periods. This is not the case for weeks, which are a pure anthropic category and are known from the literature to influence emission cycles and atmospheric chemistry. For the first time since it started data gathering operations, CO (carbon monoxide), CO2 (carbon dioxide), CH4 (methane) and eBC (equivalent black carbon) values detected by the Lamezia Terme WMO/GAW station in Calabria, Southern Italy, have been evaluated via a two-pronged approach accounting for weekly variations in absolute concentrations, as well as the number of hourly averages exceeding select thresholds. The analyses were performed on seven continuous years of measurements from 2016 to 2022. The results demonstrate that the analyzed GHGs (greenhouse gasses) and aerosols respond differently to weekly cycles throughout the seasons, and these findings provide completely new insights into source apportionment characterization. Moreover, the results have been combined into a new parameter: the hereby defined WDWO (Weighed Distribution of Weekly Outbreaks) normalizes weekly trends in CO, CO2, CH4 and eBC on an absolute scale, with the scope of providing regulators and researchers alike with a new tool meant to better evaluate anthropogenic pollution and mitigate its effects on the environment and human health.

Finishing bench tests for thermal neutralization of marine oily waters

The studies conducted on the ship's oily water thermal disposal test bench demonstrated, on the one hand, the suitability of the bench for research work, and on the other hand, revealed several unaccounted aspects in the design of the bench and its measuring system. Specifically, the nozzle was replaced to ensure finer atomization of the oily water into the flue. Additionally, it was previously established that lower pressure than originally designed was sufficient for proper atomization, necessitating the replacement of the control manometer and the electronic pressure sensor, followed by their calibration. To enable the calculation of the thermal energy characteristics of the thermal disposal process, a correlation between the pressure in the tank and the flow rate of the oily water through the nozzle was established. In a series of fine-tuning tests, data were collected on the temperature distribution along the length of the flue without and with the injection of both clean and oily water. The results indicate additional heat release when oily water is injected into the flue. The environmental characteristics of the thermal disposal process were monitored using a gas analyzer. In all the tests, the decrease of carbon monoxide concentration to almost zero was noted. Based on the results of the fine-tuning tests, it was concluded that the bench is ready for the following experiments: screening and interpolation.

On-demand release of CO in dual-responsive nanocomposite hydrogels for wound dressing

Gaseous signaling molecules, especially carbon monoxide (CO), hold promising potential for disease management. The therapeutic efficacy of CO is closely tied to its concentration, however, maintaining it at optimal levels for both efficacy and safety is highly challenging. To address this, we designed a dual-responsive (pH/red light) nanocomposite hydrogel for on-demand CO release. We first synthesized a hybrid nanocomposite (CaCO3@AgCCN) comprising a CO2 donor (CaCO3) and a photocatalyst (Ag3PO4-decorated carbon dot g-C3N4, AgCCN) capable of converting CO2 to CO. The size of CaCO3 particles was approximately 40 nm, while that of AgCCN was around 150 nm in this nanocomposite. CaCO3@AgCCN was then incorporated into chitosan (CS) to form a nanocomposite hydrogel. This nanocomposite hydrogel could respond to a mildly acidic environment due to bacterial growth, generating CO2 exactly where it is needed (the wound site), which would be subsequently catalytically converted to CO by AgCCN under 630-nm red light illumination to facilitate wound healing. The generated CO, readily controlled by adjusting the CaCO3@AgCCN content in the nanocomposite hydrogel and the red-light illumination time (the CO concentration reaching 4.7 μM after 10-min illumination), has demonstrated strong bactericidal and anti-inflammatory effects, both essential in facilitating wound healing as shown in both in vitro and in vivo studies. Coupled with satisfactory biocompatibility, this dual-responsive nanocomposite hydrogel appears to hold great promise for safe and effective applications of CO in biomedical fields.

Mortality Risks and Causes in Previous Carbon Monoxide Poisoning: A Nationwide Population-Based Cohort Study

Objectives: Carbon monoxide (CO) poisoning can cause brain, heart, and kidney injuries. We aimed to determine the association of risks of all-cause and cause-specific mortality in patients with previous CO poisoning. Design, Setting, and Patients: This population-based cohort study used data from the National Health Insurance Service database and the National Death Registry of Korea. Adult patients diagnosed with CO poisoning and controls between 2002 and 2020 were included. Patients were matched with controls on a 1:1 ratio, considering age, sex, insurance type, income level, residential location, smoking status, alcohol consumption, obesity status, medical and psychiatric illness history, and Charlson Comorbidity Index at the index date. The cohort was monitored from 2002 to 2022 or until death or emigration in terms of all-cause and cause-specific mortality. Interventions: None. Measurements and Main Results: A total of 48,600 patients with CO poisoning and matched controls were included. The cohort included 41.30% females, and the mean age was 48.05 years. Patients with CO poisoning exhibited a substantially elevated risk of all-cause mortality compared with those in the control group, with an adjusted hazard ratio (aHR) of 15.67 (95% CI, 12.58–19.51). The mortality associated with infectious (aHR, 6.71; 95% CI, 1.51–29.72), neoplasm/oncologic (aHR, 5.20; 95% CI, 3.39–7.99), endocrine (aHR, 13.44; 95% CI, 1.76–102.70), neurologic (aHR, 7.42; 95% CI, 2.91–18.90), cardiovascular (aHR, 8.97; 95% CI, 5.05–15.93), respiratory (aHR, 17.54; 95% CI, 5.48–56.17), and gastrointestinal (aHR, 24.72; 95% CI, 3.34–182.69) disorders was significantly greater in the former. Deaths due to external causes, including suicide, were significantly higher in the CO poisoning group (aHR, 50.07; 95% CI, 30.98–80.90). Conclusions: Patients with CO poisoning exhibited a heightened risk of all-cause mortality compared with the matched controls. Additionally, the cause-specific mortality risk differed between the groups.

Mechanism of Carbon Monoxide (CO) Generation and Potential Human Health Hazard during Mechanized Tunnel Driving in Organic-Rich Rocks: Field and Laboratory Study

The monitoring of carbon emissions is increasingly becoming a sustainability issue worldwide. Despite being largely unnoticed, the toxic gas carbon monoxide (CO) is ubiquitous in mechanized tunnel driving, but the individual sources, release and enrichment mechanisms are often unknown. In this study, the generation of CO from organic matter containing sedimentary rocks was investigated during mechanized tunnel driving and by reacting claystone and sandstone with 10 mM NaCl solutions for 2 months at 70 °C and 140 °C. The mineralogical and geochemical evolution of the solids and fluids was assessed by CO measurements and the XRD, DTA, TOC, IC and ICP-OES methods. The CO concentration in the atmosphere reached up to 1920 ppm (100 ppm on average) during tunnel driving, which is more than three times higher than the legal daily average dose for tunnellers, thus requiring occupational safety operations. Mineral-specific dissolution processes and the rapid decomposition of labile organic matter upon thermal alteration contributed to the liberation of CO and also carbon dioxide (CO2) from the host rocks. In mechanized tunnel driving, frictional heat and ‘cold’ combustion with temperatures reaching 50–70 °C at the drill head is an important mechanism for increased CO and CO2 generation, especially during drilling in sedimentary rocks containing significant amounts of OM and when the ventilation of the tunnel atmosphere and air mixing are limited. Under such conditions, human health damage due to CO exposure (HHDCO) can be 30 times higher compared to tunnel outlets, where CO is emitted from traffic.

CO-Free Fuel Processing of Water Gas Shift Feedstocks: Effect of Support on CuMn Spinel Performance

AbstractCleaning up carbon monoxide (CO) in water gas shift feedstocks is crucial for fuel cell applications. The catalytic transformation of CO in hydrogen-rich feeds poses a significant challenge in environmental catalysis. To address this issue, a range of Cu–Mn-based monometallic and bimetallic catalysts with diverse supports (such as alumina, silica, zirconia, and titania) were employed. Temperature programming techniques were utilised to observe the reduction and oxidation behaviours of these catalysts. The investigation involved testing CO oxidation at various temperatures over copper and manganese-based supported catalysts in the presence of H2O and CO2 (simulating realistic conditions). A positive impact of H2O on catalytic performance was noted, whereas CO2 had a suppressive effect. Furthermore, the specific support materials (Al2O3, SiO2, TiO2, and ZrO2) were studied to understand their roles in CO oxidation under realistic conditions. In the presence of water, alumina catalysts containing bimetallic metals (Cu–Mn) exhibited 100% CO conversion even at a lower temperature of 160 °C. Conversely, under the predominant influence of CO2, alumina catalyst (Cu–Mn) showed 55% CO conversion. The exceptional performance was attributed to CO preferential adsorption on highly active Cu–Mn sites and a small H2-oxidative atmosphere of the catalysts. The activity results highlighted the strong dependence of CO conversion on reaction temperatures, the presence of metals, and the types of supports. Overall, these findings suggest the potential use of these catalysts for H2 purification under realistic conditions. Graphical Abstract

Interpregnancy interval, air pollution, and the risk of low birth weight: a retrospective study in China

BackgroundBoth interpregnancy intervals (IPI) and environmental factors might contribute to low birth weight (LBW). However, the extent to which air pollution influences the effect of IPIs on LBW remains unclear. We aimed to investigate whether IPI and air pollution jointly affect LBW.MethodsA retrospective cohort study was designed in this study. The data of birth records was collected from the Jiangsu Maternal Child Information System, covering January 2020 to June 2021 in Nantong city, China. IPI was defined as the duration between the delivery date for last live birth and date of LMP for the subsequent birth. The maternal exposure to ambient air pollutants during pregnancy—including particulate matter (PM) with an aerodynamic diameter of ≤ 2.5 μm (PM2.5), PM10, ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2) and carbon monoxide (CO)—was estimated using a hybrid kriging-LUR-RF model. A novel air pollution score was proposed, assessing combined exposure to five pollutants (excluding CO) by summing their concentrations, weighted by LBW regression coefficients. Multivariate logistic regression models were used to estimate the effects of IPI, air pollution and their interactions on LBW. Relative excess risk due to interaction (RERI), attributable proportion of interaction (AP) and synergy index (S) were utilized to assess the additive interaction.ResultsAmong 10, 512 singleton live births, the LBW rate was 3.7%. The IPI-LBW risk curve exhibited an L-shaped pattern. The odds ratios (ORs) for LBW for each interquartile range increase in PM2.5, PM10, O3 and the air pollution score were 1.16 (95% CI: 1.01–1.32), 1.30 (1.06–1.59), 1.22 (1.06–1.41), and 1.32 (1.10–1.60) during the entire pregnancy, respectively. An additive interaction between IPI and PM2.5 was noted during the first trimester. Compared to records with normal IPI and low PM2.5 exposure, those with short IPI and high PM2.5 exposure had the highest risk of LBW (relative risk = 3.53, 95% CI: 1.85–6.49, first trimester).ConclusionThe study demonstrates a synergistic effect of interpregnancy interval and air pollution on LBW, indicating that rational birth spacing and air pollution control can jointly improve LBW outcomes.

Mass Carbon Monoxide Poisoning on a Train in Italy, March 1944. History Reconstructed

World War II was approaching its end in Italy in 1944 when one of the worst train disasters in world history occurred near the small town of Balvano in the Apennine Mountains. The train did not derail or crash into something as in most major train disasters. Instead, it entered a mountainous railway tunnel, and when it emerged, over 500 passengers were dead from carbon monoxide poisoning. The event was not allowed to be publicized for almost two decades. This manuscript reconstructs the story of possibly the most significant incident of carbon monoxide mortality ever recorded.

Rhodium-Catalyzed [5 + 1 + 2] Cycloaddition of Yne-3-acyloxy-1,4-enynes (YACEs) and Carbon Monoxide: Reaction Development and Mechanism

Rhodium-Catalyzed [5 + 1 + 2] Cycloaddition of Yne-3-acyloxy-1,4-enynes (YACEs) and Carbon Monoxide: Reaction Development and Mechanism

Investigation of operational settings, environmental conditions, and faults on the gas turbine performance

Abstract Gas turbine engines are complex mechanical marvels widely employed in diverse applications such as marine vessels, aircraft, power generation, and pumping facilities. However, their intricate nature renders them susceptible to numerous operational faults, significantly compromising their performance and leading to excessive emissions, consequently incurring stringent penalties from environmental regulatory bodies. Moreover, the deterioration of gas turbine performance is exacerbated by variations in working conditions based on operational settings and environmental conditions. Past studies have focused on certain working conditions that limit effectiveness in real-world applications where operational settings and environmental conditions vary during operations. The influence of these working conditions on the performance of gas turbines also needs to be assessed, as they can lead to different fault patterns resulting in unplanned maintenance, unnecessary maintenance costs, unsafe conditions and stringent penalties. This study uses the gas turbine simulation program to simulate a high-bypass turbofan engine inspired by Pratt & Whitney PW-4056, analysing the combined effects of operational settings and environmental conditions on engine performance while also incorporating simulations of common gas turbine faults like fouling and erosion in various locations and severities along the gas path. The model’s accuracy is confirmed by low mean absolute percentage errors of 0.004% of thrust at the cycle reference point and 0.15% and 0.28% at 2 km and 7 km altitudes, respectively, demonstrating the model’s robustness across varying operational scenarios. In conclusion, this research highlights the significant effects of operational settings and environmental factors on gas turbine performance, particularly impacting specific fuel consumption and thrust. The study reveals that operational settings and environmental factors significantly impact fuel consumption and thrust. Specifically, compressor fouling and low-pressure turbine erosion increase nitrogen oxide (NOx) emissions by 4.5% and 11.1%, while fouling of nozzle guide vanes and high-pressure turbine erosion raise unburned hydrocarbon by 10.0% and 20.2%, and carbon monoxide (CO) by 3.2% and 5.2%, respectively, compared to a healthy engine. These insights highlight the importance of component-specific degradation in influencing gas turbine performance and emissions.

Sensitive and selective determination of upadacitinib using a custom-designed electrochemical sensor based on ZnO nanoparticle-assisted molecularly imprinted polymer.

Upadacitinib (UPA) is a selective and reversible oral Janus kinase (JAK) 1 inhibitor and is of great importance in treating inflammatory bowel disease (Zheng et al., Int Immunopharmacol 126:111229, 2024; Foy et al., JAAD Case Rep 42:20-22, 2023). Although there are limitations to the effectiveness of UPA, it has received positive responses in clinical trials and is approved for the treatment of atopy dermatitis (AD) (Li et al., Int Immunopharmacol 125:111193, 2023). In this study, a nanoparticle-doped molecularly imprinted polymer (MIP)-based electrochemical sensor was developed for sensitive and selective detection of UPA. The developed sensor was designed as a thin film layer using the photopolymerization method on the surface of the prepared nanoparticle-doped polymerization solution glassy carbon electrode (GCE). Various nanoparticles, such as multi-walled carbon nanotube, titanium dioxide, oxide, and zinc oxide (ZnO) nanoparticles, were the most suitable for UPA. Surface characterization of the developed sensor was done by scanning electron microscopy (SEM), and electrochemical characterization was done by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The quantitative analysis of UPA was performed in 5.0mM [Fe (CN)6]3-/4- solution using the differential pulse voltammetry (DPV) technique. Under optimum conditions, the calibration range was between 0.1 and 1pM. The limit of detection (LOD) and limit of quantification (LOQ) were calculated as 0.005pM and 0.017pM, respectively. The sensor's accuracy was proven by performing a recovery study in serum. The sensor's selectivity was also evaluated using common interfering substances such as KNO3, CaCl2, Na2SO4, uric acid, ascorbic acid, dopamine, and paracetamol. According to the results obtained, the performance of the designed sensor was found to be quite sensitive and selective in determining UPA. The developed UPA-ZnO/3-APBA@MIP-GCE sensor showed high sensitivity and selectivity towards UPA. In addition, the selectivity, the most important feature of the MIP-based sensor, was confirmed by imprinting factor (IF) calculations using tofacitinib (TOF) and ruxolitinib (RUX). The sensor's unique selectivity is demonstrated by its successful performance even in the presence of UPA impurities.

Effect of iron oxidation state on the catalytic performance of Fe/C in liquid phase flow hydrogenation of 2-butyne-1,4-diol

Cis-2-butene-1,4-diol and 1,4-butanediol are crucial precursors in producing bioplastics and biodegradable plastics. Moreover, cis-2-butene-1,4-diol is used in the production of vitamins A and B6, fungicides and insecticides. On an industrial scale, they are produced by hydrogenation of 2-butyne-1,4-diol with Ni Raney as catalyst at > 160 °C and > 15 MPa. Herein, the effect of mesoporous carbon, iron loading (2, 6, 10 and 14 wt%), and metal oxidation state on the activity and selectivity of iron catalysts in the liquid phase continuous flow 2-butyne-1,4-diol hydrogenation at mild conditions (at temperature range 10–65 °C and pressure range 1–20 bar) was performed. Catalytic investigations supported by statistical modeling and physicochemical characterization (TPR, H2-TPD, physisorption, TEM, XPS, and Mössbauer spectroscopy), showed that the activity of the Fe/C can be determined by the presence of functional groups in mesoporous support which are responsible for high metal dispersion and strong metal-support interaction, which boosts the catalytic activity of iron catalysts. Additionally, the formation of metastable iron carbides which are active in hydrogenation cannot be excluded. All of the catalysts showed 100% selectivity toward cis-2-butene-1,4-diol at the lowest temperature. However, the best compromise between selectivity and activity (TOF=336 h−1) was achieved with 2 wt% Fe at 1 bar and 25 °C.

Use of Digital Technologies for the Conduct of Work in the Government System Based on the Demans of the Current Times

This article deals with the issues of ensuring the safety of the population in the residences of citizens. It is planned to implement an electronic platform that allows for quick collection and analysis of information on the technical and social condition of residential areas. These strategies focus on digital transformation in the national economy, industry, and society. In Uzbekistan, significant steps have been taken to implement modern information and communication technologies (ICT) in public administration, education, healthcare, and agriculture. One notable challenge addressed in this study is the management of carbon monoxide poisoning, fire hazards, and explosions during the heating season. The research highlights the limitations of manual data collection, including the risk of data loss, difficulty in locating information, and inefficiencies in processing critical safety data. The program processes data in less than a minute, facilitating more efficient emergency management and preventive measures. This system exemplifies the role of digital technology in enhancing public safety and optimizing government operations.

An effective and efficient approach for smoke control in underground parking garages

Underground parking garages are enclosed spaces not directly exposed to the exterior. A smoke control system is typically required to facilitate occupants’ safe evacuation/relocation and assist in firefighting/rescue. Currently, there is a lack of guidelines for designing such systems in primary codes/standards. Only a limited number of local authorities have developed amendments to address this issue. These amendments either rely on outdated approaches, such as air change method, or simply repurpose carbon monoxide ventilation systems for smoke control without conducting additional engineering analysis and providing justification. The intent of this study is to examine the adopted approaches and explore an effective and efficient approach for garage smoke control. According to the study’s findings, it is discovered that garage floor height significantly impacts the performance of smoke control system. Additionally, structural components (beams) also influence the performance of smoke control system. Moreover, this study derives a linear equation to ascertain available safe egress time (ASET) when utilizing the carbon monoxide ventilation system or typical air change methods. Taking cost into consideration, the study concludes that for effective and cost-efficient smoke control in large underground garages, employing a carbon monoxide ventilation system is preferable to the traditional or equivalent air change method.

Chest wall muscle area, ventilatory efficiency and exercise capacity in systemic sclerosis.

To investigate the potential contribution of chest wall muscle area (CWMA) to the ventilatory efficiency and exercise capacity in patients with Systemic Sclerosis (SSc) without interstitial lung disease (ILD). Forty-four consecutive SSc patients [F = 37, median age 53.5years (IQR 43.5-58)] were examined using chest high-resolution computed tomography (HRCT), pulmonary function tests and cardiopulmonary exercise testing (CPET). The CWMA was evaluated at the level of the ninth thoracic vertebra on CT images by two independent evaluators blinded to the patient information. CPET parameters analyzed were maximum oxygen uptake (VO2 max) and VO2 at anaerobic threshold (VO2@AT); minute ventilation (VE); maximum tidal volume (VT). A statistically significant positive correlation was found between CWMA and maximum workload (r = 0.470, p < 0.01), VO2 max ml/min (r = 0.380, p < 0.01), VO2@AT (r = 0.343, p < 0.05), VE (r = 0.308, p < 0.05), VT (r = 0.410, p < 0.01) and VO2/heart rate (r = 0.399, p < 0.01). In multiple regression analysis, VO2 max (ml/min) was significantly associated with CWMA [β coefficient = 5.226 (95% CI 2.824, 7.628); p < 0.001], diffusing capacity for carbon monoxide (DLco) [β coefficient = 6.749 (95% CI 1.460, 12.039); p < 0.05] and body mass index (BMI) [β coefficient = 41.481 (95% CI 8.802, 74.161); p < 0.05]. In multiple regression analysis, maximum workload was significantly associated with CWMA [β coefficient = 0.490 (95% CI 0.289, 0.691); p < 0.001], DLco [β coefficient = 0.645 (95% CI 0.202, 1.088); p < 0.01] and BMI [β coefficient = 3.747 (95% CI 1.013, 6.842); p < 0.01]. In SSc-patients without ILD, CWMA represents an important variable in exercise capacity and can be evaluated by the mediastinal window available in the HRCT images required for lung disease staging.

Spectrophotometric Determination of Biopolymers in Alabama Benchmark Soils

Biopolymers are organic polymers synthesized by biological organisms. Cellulose, lignin, and proteins are important soil biopolymers known to bind soil particles to improve or strengthen soil structures and support agricultural productivity. In this study, we spectrophotometrically determined the amount of soil cellulose, acetyl bromide lignin, and autoclaved citrate extractable protein in soils in relation to other soil properties. Results showed acetyl bromide lignin &gt; cellulose &gt; autoclaved citrate extractable protein. High clay soils have relatively higher amounts of cellulose and lignin but have lower protein content. The coefficient of variation (CV) of the three biopolymers in the soils studied was autoclaved citrate extractable protein (56.8%), &gt;cellulose (55.2%), &gt;acetyl bromide lignin (44.7%). Pearson correlation analysis showed that soil cellulose was significantly related to cation exchange capacity (CEC), total nitrogen, soil organic matter, and available phosphorus. An increase in soil acetyl bromide lignin suggested an increase in soil organic matter and lower soil available phosphorus. Soil autoclaved citrate extractable protein was significantly correlated with extractable acidity. However, cellulose, acetyl bromide lignin, and autoclaved citrate extractable protein were not significantly correlated with permanganate oxidizable carbon (POxC), electrical conductivity (EC), and C:N ratio. We assume that the concentrations of biopolymers in soils are an intrinsic soil characteristic and contribute to general soil health and productivity.

Constructing CO-immune water dissociation sites around Pt to achieve stable operation in high CO concentration environment

The serious problem of carbon monoxide (CO) poisoning on the surface of Pt-based catalysts has long constrained the commercialization of proton exchange membrane fuel cells (PEMFCs). Regeneration of Pt sites by maintaining CO scavenging ability through precise construction of the surface and interface structure of the catalyst is the key to obtaining high-performance CO-resistant catalysts. Here, we used molybdenum carbide (MoCx) as the support for Pt and introduced Ru single atoms (SA-Ru) at the Pt-MoCx interface to jointly decrease the CO adsorption strength on Pt. More importantly, the MoCx and SA-Ru are immune to CO poisoning, which continuously assists in the oxidation of adsorbed CO by generating oxygen species from water dissociation. These two effects combine to confer this anode catalyst (SA-Ru@Pt/MoCx) remarkable CO tolerance and the ability to operate stably in fuel cell with high CO concentration (power output 85.5 mW cm−2@20,000 ppm CO + H2 – O2), making it possible to directly use the cheap reformed hydrogen as the fuel for PEMFCs.

Study on CO dispersion characteristics and isolation door control technology of refuge chamber in coal mine

To investigate the dispersion process of the underground toxic gas carbon monoxide (CO) into the refuge chamber during a mine disaster and enhance the survival rate of trapped miners, a simplified model of an underground refuge chamber and the main roadway was constructed. The impact of temperature and pressurized air volume on CO dispersion into the refuge chamber has been examined through both analog experiments and numerical simulations, and the reliability of the simulation results was verified. The results indicate that CO dispersion into the refuge chamber through the top of the protective isolation door occurs when the temperature in the refuge chamber is lower than that of the toxic gas. When the temperature of the toxic gas is higher, it tends to enter the refuge chamber through the bottom of the protective isolation door. The evolution of CO concentration in the transition chamber can be divided toxic survival chamber can be categorized into a sudden decline stage and a stable stage. And a flexible isolation door designed to control the entry of toxic gases into the refuge chamber was implemented, and its impact on CO dispersion has been compared and analyzed. When the temperature of the main roadway is 50 °C and the temperature of the refuge chamber is 20 °C, the required pressurized air volume to maintain the CO concentration within the safe threshold (24 ppm) is reduced to 69.6% of that needed without the isolation door, thereby significantly reducing the infiltration of harmful gases from the main roadway into the refuge chamber.

A VMD-LSTNet-Attention model for concentration prediction of mixed gases

Gases typically exist as mixed states, which normally contain more information and exhibit more intricate features than single gas. Hence, the task of predicting mixed gas concentrations poses a challenging endeavor in the field of gas detection. In this study, a Variational Mode Decomposition method was combined with Long and Short-term Time-series Network-Attention to build a VMD-LSTNet-Attention model, based on which the response signals of electronic nose (E-nose) is processed, achieving a high-precision concentrations prediction of carbon monoxide (CO) and ethylene mixed gases. Firstly, a dataset containing the raw response signals of CO and ethylene was collected using an gas data collection system. Then, VMD algorithm was used to extract and decompose the essential features from the E-nose signals into multiple components. Further, in pursuit of optimal decomposition results, Particle Swarm Optimization (PSO) algorithm was employed to optimize the penalty factor α and determine the most effective decomposition level K. Subsequently, the LSTNet-Attention model was employed to analyze the concentrations of mixed gases, and the predictive R-square values for CO and ethylene reach 0.993 and 0.975, respectively. Finally, the comparison with the traditional deep learning models and the popular models demonstrates the effectiveness of the proposed VMD-LSTNet-Attention model for concentration prediction of mixed gases.