Search

Carbon monoxide (CO) delivery molecules are of significant current interest as potential therapeutics, including for anticancer applications. A recent approach toward generating new types of materials-based anticancer agents involves combining the Fenton reactivity of a redox active metal ion with CO delivery. However, small molecule examples of these types of entities have not been systematically studied to evaluate the combined effect on cellular toxicity. Herein we describe a Cu(II) flavonolato complex which produces anticancer effects through a combination of copper-mediated reactive oxygen species (ROS) generation and light-induced flavonol CO release. Confocal microscopy studies provide evidence of enhanced flavonol uptake in the copper flavonolato system relative to the free flavonol, which leads to an increased amount of CO delivery within cells. Importantly, this work demonstrates that a metal flavonolato species can be used to produce enhanced toxicity effects resulting from both metal ion-induced Fenton reactivity and increased cellular uptake of a flavonol CO donor., (© 2024 Wiley-VCH GmbH.)

The rapid urbanization and industrialization have caused a significant increase in environmental pollution, especially in air quality. This paper introduces an IoT-based environmental monitoring system to address these issues. Using state-of-the-art IoT technology, the system deploys sensors in key locations to continuously collect data on air quality indicators like Particulate Matter (PM), Carbon Monoxide (CO), and Ozone (O3). The collected data is wirelessly transmitted to a central server for processing and analysis. The system provides real-time and historical data through a user-friendly interface, enabling users to monitor current conditions, identify trends, and identify potential pollution sources. The key features include scalability, allowing for the addition of new sensors, and proactive decision-making through alerts when environmental parameters exceed predefined thresholds. This paper aims to empower communities with the knowledge needed to address and mitigate air pollution, creating healthier and more liveable urban environments in the face of rapid global urbanization. [ABSTRACT FROM AUTHOR]

This paper provides a comprehensive review of the fundamental impacts of excess air ratio (λ) on emissions and engine performance in spark-ignition engines. It examines pollutants such as oxides of nitrogen, unburned hydrocarbons, and carbon monoxide under both lean and ultra-lean conditions. In this paper, mainly the most prominent, up to date, and effective technologies such as ignition strategy, injection strategy, fuel blending, pre-chamber addition, are included. In addition to the effect the excess air ratio has on emissions, engine performance and efficiency are reviewed. This is done through the analysis of the Indicated Mean Effective Pressure, Coefficient of Variation, Fuel Consumption and Indicated Thermal Efficiency. The topics discussed relate to the primary categories listed above, but they are not exclusive to them. The paper concludes with a summary of findings and offers recommendations for future research directions.. [ABSTRACT FROM AUTHOR]

In this article, the formation of laser-induced graphene on the two natural polymers, cellulose, and lignin, as precursors was investigated with molecular dynamics simulations and some experiments. These eco-friendly polymers provide significant industrial advantages due to their low cost, biodegradability, and recyclable aspects. It was discovered during the simulation that LIG has numerous defects and a porous structure. Carbon monoxide, H2, and water vapor are gases released by cellulose and lignin substrates. H2O and CO are released when the polymer transforms into an amorphous structure. Later on, as the amorphous structure changes into an ordered graphitic structure, H2 is released continuously. Since cellulose monomer has a higher mass proportion of oxygen (49%) than lignin monomer (29%), it emits more CO. The LIG structure contains many 5- and 7-carbon rings, which cause the structure to have bends and undulations that go out of the plane. In addition, to verify the molecular dynamics simulation results with experimental tests, we used a carbon dioxide laser to transform filter paper, as a cellulose material, and coconut shell, as a lignin material, into graphene. Surprisingly, empirical experiments confirmed the simulation results. [ABSTRACT FROM AUTHOR]

Syngas and CO-rich off-gases are key chemical platforms to produce biofuels and bioproducts. From the perspective of optimizing and up-scaling CO co-digestion with organic waste streams, this study aims at assessing and quantifying the inhibitory effects of CO on acidogenic glucose fermentation and aceticlastic methanogenesis. Mesophilic cultures were fed in two sets of batch assays, respectively, with glucose and acetate while being exposed to dissolved CO in equilibrium with partial pressures in the range of 0.25-1.00 atm. Cumulative methane production and microbial monitoring revealed that aceticlastic methanogenic archaea were significantly inhibited (2-20 % of the methane production of CO non-exposed cultures). The acidogenic glucose degrading community was also inhibited by CO, although, thanks to its functional redundancy, shifted its metabolism towards propionate production. Future work should assess the sensitivity of hereby estimated CO inhibition parameters, e.g., on the simulation output of a continuous syngas co-digestion process with organic substrates., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Carbon monoxide (CO) has emerged as a potential antitumor agent by inducing the dysfunction of mitochondria and the apoptosis of cancer cells. However, it remains challenging to deliver appropriate amount of CO into tumor to ensure efficient tumor growth suppression with minimum side effects. Herein we developed a CO prodrug-loaded nanomedicine based on the self-assembly of camptothecin (CPT) polyprodrug amphiphiles. The polyprodrug nanoparticles readily dissociate upon exposure to endogenous H 2 O 2 in the tumor, resulting in rapid release of CPT and generation of high-energy intermediate dioxetanedione. The latter can transfer the energy to neighboring CO prodrugs to activate CO production by chemiexcitation, while CPT promotes the generation of H 2 O 2 in tumors, which in turn facilitates cascade CPT and CO release. As a result, the polyprodrug nanoparticles display remarkable tumor suppression in both subcutaneous and orthotopic breast tumor-bearing mice owing to the self-augmented CPT release and CO generation. In addition, no obvious systemic toxicity was observed in mice treated with the metal-free CO prodrug-loaded nanomedicine, suggesting the good biocompatibility of the polyprodrug nanoparticles. Our work provides new insights into the design and construction of polyprodrug nanomedicines for synergistic chemo/gas therapy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: While extensive studies have elucidated the relationships between exposure to air pollution and chronic diseases, such as cardiovascular disorders and diabetes, the intricate effects on specific kidney diseases, notably primary glomerulonephritis (GN)-an immune-mediated kidney ailment-are less well understood. Considering the escalating incidence of GN and conspicuous lack of investigative focus on its association with air quality, investigation is dedicated to examining the long-term effects of air pollutants on renal function in individuals diagnosed with primary GN., Methods: This retrospective cohort analysis was conducted on 1394 primary GN patients who were diagnosed at Seoul National University Bundang Hospital and Seoul National University Hospital. Utilizing time-varying Cox regression and linear mixed models (LMM), we examined the effect of yearly average air pollution levels on renal function deterioration (RFD) and change in estimated glomerular filtration rate (eGFR). In this context, RFD is defined as sustained eGFR of less than 60 mL/min per 1.73 m 2 ., Results: During a mean observation period of 5.1 years, 350 participants developed RFD. Significantly, elevated interquartile range (IQR) levels of air pollutants-including PM 10 (particles ≤10 micrometers, HR 1.389, 95 % CI 1.2-1.606), PM 2.5 (particles ≤2.5 micrometers, HR 1.353, 95 % CI 1.162-1.575), CO (carbon monoxide, HR 1.264, 95 % CI 1.102-1.451), and NO 2 (nitrogen dioxide, HR 1.179, 95 % CI 1.021-1.361)-were significantly associated with an increased risk of RFD, after factoring in demographic and health variables. Moreover, exposure to PM 10 and PM 2.5 was associated with decreased eGFR., Conclusions: This study demonstrates a substantial link between air pollution exposure and renal function impairment in primary GN, accentuating the significance of environmental determinants in the pathology of immune-mediated kidney diseases., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Anemia is common in low- and middle-income countries (LMICs), causing significant health issues and social burdens. Exposure to household air pollution from using biomass fuels for cooking and heating has been associated with anemia, but the exposure-response association has not been studied., Objectives: We evaluated the associations between personal exposure to air pollution and both hemoglobin levels and anemia prevalence among pregnant women in a multi-country randomized controlled trial., Methods: We studied 3,163 pregnant women aged 18-35 years with 9-20 weeks of gestation, recruited as part of the Household Air Pollution Intervention Network (HAPIN) randomized controlled trial in Guatemala, India, Peru, and Rwanda. We assessed 24-hour personal exposures to fine particulate matter (PM 2.5 ), black carbon (BC), and carbon monoxide (CO), and measured hemoglobin levels at baseline (15 ± 3 weeks gestation). Linear and logistic regression models were used to examine the associations of measured pollutants with hemoglobin levels and anemia prevalence, adjusting for confounding., Results: Single-pollutant models showed associations of CO with higher hemoglobin levels and lower anemia prevalence. Bipollutant models involving CO and PM 2.5 also revealed that an interquartile range (IQR) increase in CO concentrations (2.26 ppm) was associated with higher hemoglobin levels [β = 0.04; 95 % confidence interval (CI): 0.01, 0.07], and a lower odds of anemia prevalence [odds ratios (OR) = 0.90; 95 % CI: 0.83, 0.98]. PM 2.5 was inversely related to hemoglobin and positively associated with anemia, but results were not statistically significant at the 0.05 alpha level. County-specific results showed that 3 of 4 countries showed a similar association between CO and hemoglobin. We found no association of BC levels with hemoglobin levels or with anemia prevalence., Conclusion: Our findings suggest that exposure to CO is associated with higher hemoglobin and lower anemia prevalence among pregnant women, whereas PM 2.5 showed the opposite associations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Fluorescence sensing and imaging techniques are being widely studied for detecting carbon monoxide (CO) in living organisms due to their speed, sensitivity, and ease of use to biological systems. Most fluorescent probes used for this purpose are based on heavy metal ions like Pd, with a few using elements like Ru, Rh, Ir, Os, Tb, and Eu. However, these metals can be expensive and toxic to cells. There is a need for more affordable and biologically safe fluorescent probes for CO detection. Drawing inspiration from the robust affinity exhibited by heme iron toward CO, in this work, a rhodamine derivative called RBF was developed for imaging CO in living cells by binding to Fe(III) and could be used for CO sensing. A Fe(III)-based fluorescent probe for CO imaging in living cells offers advantages of cost effectiveness, low toxicity, and ease of use. The fluorescence detection using the RBF-Fe system showed a direct correlation with increasing levels of CORM-3 (LOD = 146 nM) or the exposure time of CO gas, displaying reduced fluorescence. A CO test paper based on RBF-Fe was created for simple on-site CO detection, where fluorescence would diminish in response to CO exposure, allowing rapid (2 min) visual identification. Imaging of CO in living cells was successfully conducted using the probe system, showing a decrease in fluorescence intensity as CORM-3 concentrations increased, indicating its effectiveness in monitoring CO levels accurately within living cells.

Carbon monoxide (CO) is an innate signaling molecule that can regulate immune responses and interact with crucial elements of the circadian clock. Moreover, pharmacologically, CO has been substantiated for its therapeutic advantages in animal models of diverse pathological conditions. Given that an excessive level of CO can be toxic, it is imperative to quantify the necessary amount for therapeutic use accurately. However, estimating gaseous CO is notably challenging. Therefore, novel techniques are essential to quantify CO in therapeutic applications and overcome this obstacle precisely. The classical Myoglobin (Mb) assay technique has been extensively used to determine the amount of CO-release from CO-releasing molecules (CORMs) within therapeutic contexts. Nevertheless, specific challenges arise when applying the Mb assay to evaluate CORMs featuring innovative molecular architectures. Here, we report a fluorinated photo-CORM (CORM-FBS) for the photo-induced CO-release. We employed the 19 F NMR spectroscopy approach to monitor the release of CO as well as quantitative evaluation of CO release. This new 19 F NMR approach opens immense opportunities for researchers to develop reliable techniques for identifying molecular structures, quantitative studies of drug metabolism, and monitoring the reaction process., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The object of the study is the selective dispersion of dangerous parameters of the gas environment during material fires. The practical importance of research consists in using the difference of sample dispersions of dangerous parameters of the gas environment on the intervals of absence and presence of ignition of materials for detection of ignition. The theoretical substantiation of the method of detecting fires in premises based on sample dispersions of current measurements of an arbitrary dangerous parameter of the gas environment, corresponding to the general populations of reliable absence and presence of fire, has been carried out. The method, at a given level of significance, determines the unbiased uniformly most powerful fire detection rule. This makes it possible to determine how much differences in sample variances are significant with a given level of significance and are caused by ignition or are random factors. Laboratory experiments were conducted to verify the proposed method. It was established that the influence of ignition on the value of the difference in the sample dispersion at the corresponding intervals of monitoring the carbon monoxide concentration, smoke density, and temperature of the gaseous environment of the laboratory chamber is different and depends on the type of ignition material. At the same time, the minimum difference of the sample dispersions is characteristic for observing the smoke density for all the studied materials. However, early detection of ignition of alcohol, paper, wood, and textiles when observing the smoke density is carried out when the threshold is exceeded by 9.01, 5.31, 2.13 and 2.55 times, respectively. It is shown that the method of early detection of fires, which is based on the detection of significant differences in sample dispersions of data from the relevant general populations. [ABSTRACT FROM AUTHOR]

Reducing the use of fossil fuels is critical to human society. In recent years, electrocatalytic carbon dioxide (CO2) reduction has attracted widespread attention. A suitable CO2 reduction catalyst is essential to convert CO2 into more valuable chemical products with high selectivity and efficiency. In this paper, a highly selective ZnAlCe-Ternary metal hydroxides (ZnAlCe-THs) nanocomposite electrocatalyst material was designed and prepared, and its performance as an electrocatalyst for catalytic reduction of CO2 to carbon monoxide (CO) was explored. The layered structure of ZnAlCe-THs nanocomposites facilitates electron transfer as well as CO2 and proton transfer, providing a high specific surface area for the electroactive sites of the electrocatalytic reduction reaction. At the same time, the ZnAlCe-THs catalyst generates CO at an overpotential of − 0.5 V. At − 1.2 V versus the reversible hydrogen electrode (vs. RHE), the bias current density is about 10.46 mA cm−2 with high selectivity of 89.3% Faraday efficiency. Its excellent electrochemical properties make it a good catalyst for the selective reduction of CO2 to CO. In this paper, ZnAlCe-Ternary mental hydroxides (ZnAlCe-THs) with a layered hydrotalclike structure were prepared by hydrothermal and co-precipitation methods. It showed excellent catalytic performance in the electrocatalytic reduction of carbon dioxide to carbon monoxide with a Faraday efficiency of 89.3% at − 1.2 V vs. RHE and a current density of 10.46 mA cm−2 for higher selectivity for CO. In addition, the ZnAlCe-THs catalyst is stable and it can operate for 5 h without particularly significant deactivation. [ABSTRACT FROM AUTHOR]

In order to increase the catalytic activity of the Pd(II)-complexes in the alcoxycarbonylation of 1-olefins, the presence in solution of a strong Brönsted acid together with a phosphine ligand is usually required. From an industrial point of view, such two additives, however, influenced the sustainability of the process mainly caused by the related corrosion of the reaction vessel and the toxicity of the phosphine ligand. In this paper, the methoxycarbonylation of 1-octene has been efficiently carried out by using the [Pd(TsO)2(PPh3)2]/FeCl3 catalyst system. The catalyst is very active also without addition of PPh3, reaching the TON of ca. 1300 (mol/mol) in 2 hours by using the Fe(III)/Pd(II) = 400/1 (mol/mol) system. Such value is higher than the values obtained by using the traditional strong Brönsted acid TsOH or other Lewis acid such as AlCl3, in the presence of PPh3. The reaction takes place with the formation of two isomeric products of linear and branched structures with a yield towards the linear isomer of ca. 80%. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) formation has been observed during composting of various fractions of organic waste. It was reported that this production can be biotic, associated with the activity of microorganisms. However, there are no sources considering the microbial communities producing CO production in compost. This preliminary research aimed to isolate and identify microorganisms potentially responsible for the CO production in compost collected from two areas of the biowaste pile: with low (118 ppm) and high CO concentration (785 ppm). Study proved that all isolates were bacterial strains with the majority of rod-shaped Gram-positive bacteria. Both places can be inhabited by the same bacterial strains, e.g. Bacillus licheniformis and Paenibacillus lactis. The most common were Bacillus (B. licheniformis, B. haynesii, B. paralicheniformis, and B. thermolactis). After incubation of isolates in sealed bioreactors for 4 days, the highest CO levels in the headspace were recorded for B. paralicheniformis (>1000 ppm), B. licheniformis (>800 ppm), and G. thermodenitrificans (∼600 ppm). High CO concentrations were accompanied by low O 2 (<6%) and high CO 2 levels (>8%). It is recommended to analyze the expression of the gene encoding CODH to confirm or exclude the ability of the identified strains to convert CO 2 to CO., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Carbon monoxide (CO) is a poisonous gas produced by incomplete combustion of carbon-based fuels that is linked to mortality and morbidity. Household air pollution from burning fuels on poorly ventilated stoves can lead to high concentrations of CO in homes. There are few datasets available on household concentrations of CO in urban areas of sub-Saharan African countries. CO was measured every minute over 24 h in a sample of homes in Nairobi, Kenya. Data on household characteristics were gathered by questionnaire. Metrics of exposure were summarised and analysis of temporal changes in concentration was performed. Continuous 24-h data were available from 138 homes. The mean (SD), median (IQR) and maximum 24-h CO concentration was 4.9 (6.4), 2.8 (1.0-6.3) and 44 ppm, respectively. 50% of homes had detectable CO concentrations for 847 min (14h07m) or longer during the 24-h period, and 9% of homes would have activated a CO-alarm operating to European specifications. An association between a metric of total CO exposure and self-reported exposure to vapours >15 h per week was identified, however this were not statistically significant after adjustment for the multiple comparisons performed. Mean concentrations were broadly similar in homes from a more affluent area and an informal settlement. A model of typical exposure suggests that cooking is likely to be responsible for approximately 60% of the CO exposure of Nairobi schoolchildren. Household CO concentrations are substantial in Nairobi, Kenya, despite most homes using gas or liquid fuels. Concentrations tend to be highest during the evening, probably associated with periods of cooking. Household air pollution from cooking is the main source of CO exposure of Nairobi schoolchildren. The public health impacts of long-term CO exposure in cities in sub-Saharan Africa may be considerable and should be studied further., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Sean Semple reports financial support was provided by UKRIMedical Research Council. Sean Semple reports financial support was provided by Kenya National Research Fund. Sean Semple reports financial support was provided by Wellcome Public Engagement Fund. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Microbial electrosynthesis (MES) is an electrically driven technology that can be used for converting CO/CO 2 into chemicals. The unique electronic and substrate properties of CO make it an important research target for MES. However, CO can poison the cathode and increase the overpotential of hydrogen evolution reaction (HER), thus reducing the electron transfer rate via H 2 . This work evaluated the effect of an anti-CO HER catalyst on the performance of MES for CO/CO 2 conversion. ZnMo-metal-organic framework (MOF) materials with different calcination temperatures were synthesized. ZnMo-MOF-800 with Mo 2 C nanoparticles as active centers exhibited excellent resistance to CO toxicity. It also obtained the highest hydrogen evolution and enhanced electron transfer rate in CO atmosphere. MES with ZnMo-MOF-800 cathode and Clostridium ljungdahlii as biocatalyst obtained 0.31 g L -1  d -1 acetate yield, 0.1 g L -1  d -1 butyrate yield, and 0.09 g L -1  d -1 2,3-butanediol yield in CO/CO 2 , while Pt/C only get 0.076 g L -1  d -1 acetate yield, 0.05 g L -1  d -1 butyrate yield and 0.02 g L -1  d -1 2,3-butanediol yield. ZnMo-MOF-800 was conducive to biofilm formation, enabling it to better resist CO toxicity. This work provides new opportunities for constructing a highly efficient cathode with an anti-CO hydrogen evolution catalyst to enhance CO/CO 2 conversion in MES., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Carbon monoxide (CO) as an endogenous gas signaling molecule possesses important physiological functions and is of great significance in the treatment of various diseases. Real-time tracking of CO in living organisms has become a research hotspot in recent years. This article presents a lysosomal targeted near-infrared ratio fluorescence probe (TBM-CO) for selective detection of CO based on the dicyanoisophorone skeleton and morpholine fragment. The probe TBM-CO with weak ICT effect can be transformed to precursor TBM-NH 2 with strong ICT effect by the traditional Tsuji-Trost reaction procession in the presence of Pd 2+ ions. The mechanism was proved by DFT calculation or the MS and HPLC results respectively. In the near-infrared region an obvious ratio fluorescence intensity change (F 686 / F 616 ) is observed in vitro spectral experiments. The concentration titration experiments indicate that there is a good liner relationship between the ratio fluorescence intensity and the concentration in the range of 0 to 50 μM (R 2  = 0.996) and the detection limit is calculated as 0.38 μM. The cell fluorescence imaging and co-localization experiments further demonstrate that TBM-CO is able to detect the exogenous and endogenous CO in lysosomal subcellular organelle. Finally, it was used to detect the changes of CO concentration in living mice successfully. In short, a probe with three advantages of near-infrared emission, ratiometric fluorescence and organelle targeting was reported and used to detect CO successfully in cells and in living mice., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The scientific paper conducted empirical studies related to the effectiveness of the use of dimethyl ether as an additive to diesel fuel and its impact on the efficiency of the mixture creation and combustion process. The measure of the above quality was the observation and parametric assessment of the then generated vibroacoustic processes, the relations of which were assessed using the peak and effective value of vibration accelerations, and also assessment of toxic exhaust gas components. The transformation of the main process into its vibroacoustic and emission representations allowed for the construction of mathematical relations between them, expressed in a specific engine operating space, and a vector of tribological parameters, expressing specific friction changes occurring in the critical kinematic pairs of the combustion and mixture formation area. The tests were carried out on a single-cylinder research engine with direct fuel injection, in stationary conditions with a time-invariant control vector. As part of the procedures, a constant and optimal value of thermodynamic parameters defining the thermal state of the engine was maintained, minimizing external forces and disturbances that could affect the active value of the measurement signal. The research results are empirical vibroacoustic and emission characteristics for various signal domains and their parameterization supplemented with a detailed analysis of the results, developed vibroacoustic and emission mathematical models depending on the operating parameters, type of fuel and combustible mixture formation variables, supplemented with an assessment of their degree of mapping to the dynamic source process. The dimethyl ether application resulted in a emission reduction by the coefficient: 24.3-57.8 (hydrocarbons), 1.03-1.24 (carbon monoxide), and an increase in nitrogen oxides in the range of 1.01-1.08. The use of dimethyl ether as a base fuel component has a positive effect on reducing the peak value of vibration accelerations in the range of 16-28%, and the root mean square in the range of 14-65%. [ABSTRACT FROM AUTHOR]

Clostridium autoethanogenum can to convert waste gases (CO 2 , CO, H 2 ) and xylose from hydrolyzed biomass into acetate, lactate, formate, ethanol and 2,3-butanediol, being a candidate for the transformation of waste streams of lignocellulosic biorefineries. Electro-fermentation (EF) modify the pattern of traditional fermentations resulting in improved product yields as has been shown when using Clostridium strains. The aim of this work was to evaluate the influence of pH on microbial growth and product distribution during fermentation and EF of xylose by C. autoethanogenum DSM10061. Fermentation and EF were carried out in a H-type reactor at three controlled pH: 5.0, 5.5 and 5.8, and at a fixed potential of -600 mV (versus Ag/AgCl) in the EF. The experiments showed that maximum biomass concentration increased as the pH increased in fermentation and EF. In accordance with maximum biomass reached, the highest substrate conversion was observed at pH 5.8 for both systems, with 76.80 % in fermentation and 96.18 % in EF. Moreover, the highest concentrations of acetic acid (1.41 ± 0.07 g L -1 ) and ethanol (1.45 ± 0.15 g L -1 ) were obtained at the end of cultures in the EF at pH 5.8. The production of lactic and formic acid decreased by the application of the external potential regardless of the pH value, reaching the lowest productivity at pH 5.8. In contrast, the specific productivity of acetic acid and ethanol was lower in both fermentation and EF at the lowest pH. Furthermore, the presence of 0.06 g L -1 of 2,3-butanediol was only detected in EF at pH 5.8. The results revealed that EF modulated microbial metabolism, which can be explained by a possible increased generation of NADP + /NADPH cofactors, which would redirect the metabolic pathway to more reduced products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Current evidence suggests that airborne pollutants have a detrimental effect on fetal growth through the emergence of small for gestational age (SGA) or term low birth weight (TLBW). The study's objective was to critically evaluate the available literature on the association between environmental pollution and the incidence of SGA or TLBW occurrence. A comprehensive literature search was conducted across Pubmed/MEDLINE, Web of Science, Cochrane Library, EMBASE, and Google Scholar using predefined inclusion and exclusion criteria. The methodology adhered to the PRISMA guidelines. The systematic review protocol was registered in PROSPERO with ID number: CRD42022329624. As a result, 69 selected papers described the influence of environmental pollutants on SGA and TLBW occurrence with an Odds Ratios (ORs) of 1.138 for particulate matter ≤ 10 μm (PM10), 1.338 for particulate matter ≤ 2.5 μm (PM2.5), 1.173 for ozone (O3), 1.287 for sulfur dioxide (SO2), and 1.226 for carbon monoxide (CO). All eight studies analyzed validated that exposure to volatile organic compounds (VOCs) is a risk factor for SGA or TLBW. Pregnant women in the high-risk group of SGA occurrence, i.e., those living in urban areas or close to sources of pollution, are at an increased risk of complications. Understanding the exact exposure time of pregnant women could help improve prenatal care and timely intervention for fetuses with SGA. Nevertheless, the pervasive air pollution underscored in our findings suggests a pressing need for adaptive measures in everyday life to mitigate worldwide environmental pollution. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) gas sensors are widely used, especially for environmental monitoring in confined spaces such as the landscape of mining cave ruins in mining parks, which is essential for ensuring the health and safety of tourists and staff. In this paper, a flexible CO gas sensor based on polyimide, interdigital electrodes, and reduced graphene oxide (RGO)/cuprous chloride (CuCl) composite film is designed and manufactured for reliable room temperature detection of high-concentration CO gas. The structure size of RGO/CuCl gas-sensitive film is 5 × 5 mm. The RGO with a 62.65% C-C bond is prepared by the thermal reduction method. The test results show that the sensor has a high response in the range of 400–2000 ppm CO gas concentration, and the maximum response is 1.56. The linear correlation coefficient of the sensor is 0.981, which indicates that the sensor has good output response characteristics. The response time of the sensor for 400 ppm CO gas is 332 s, which indicates that the sensor has a fast response rate. Furthermore, compared with other gases, the sensor shows higher gas selectivity for CO gas. This sensor has the characteristics of small size and easy attachment; therefore, it can be installed on the shoulder or helmet of tourists' safety suits, providing personalized real-time warning prompts for tourists' physical health status. [ABSTRACT FROM AUTHOR]

In a global society that is increasingly interrelated and focused on mobility, carbon monoxide emissions derived from internal combustion vehicles remain the most important factor that must be addressed to improve environmental quality. Certainly, air pollution generated by internal combustion engines threatens human health and the well-being of the planet. In this regard, this paper aims to address the urgent need to understand and face the CO emissions produced by internal combustion vehicles; therefore, this work proposes a mathematical model based on Auto-Regressive Exogenous that predicts the CO percentages produced by an internal combustion engine during its start-up. The main goal is to establish a strategy for diagnosing excessive CO emissions caused by changes in the engine temperature. The proposed CO emissions modeling is evaluated under a real dataset obtained from experiments, and the obtained results make the proposed method suitable for being implemented as a novel diagnosis tool in automotive maintenance programs. [ABSTRACT FROM AUTHOR]

Copper-containing sludge is a common by-product of industrial activities, particularly electroplating and metal processing. This type of sludge contains high concentrations of heavy metals such as copper, which can pose a potential threat to the environment. Therefore, its treatment and disposal require special attention. Due to its efficient mass and heat transfer characteristics, the suspended state technology has shown significant potential for application in a number of key processes, including the drying, decomposition, and reduction of copper-containing sludge. This paper presents an in-depth analysis of the current status of the application of the suspended state technology in the treatment of copper-containing sludge. Based on this analysis, a device for the treatment of copper-containing sludge in the suspended state was designed, through which the characteristics of copper-containing sludge in the oxidative decomposition and reduction phases are investigated. The research objects were gas concentration, temperature, contact state, and particle size time. Orthogonal experiments were initially employed to investigate the relationship between the influencing factors and the conversion rate of copper oxides. This was followed by a single-factor influence study, which led to the determination of the optimal process parameters for the decomposition experiments of the Cu-containing sludge in an oxidizing atmosphere. The 100 μm Cu-containing sludge was reacted with 10% O2 gas at a flow rate of 1 m/s for 3 min under the condition of 900 °C. The process parameters were then determined as follows: The research objects were gas concentration, temperature, contact state, and particle size time. Orthogonal experiments were employed to investigate the relationship between the influencing factors and the copper conversion rate. This was followed by a single-factor influence study, which determined the optimal process parameters for the copper-containing sludge reduction experiments. The 200 μm copper-containing sludge was reacted for 5 min at a flow rate of 7% carbon monoxide at a flow rate of 1.5 m/s under the condition of 800 °C. [ABSTRACT FROM AUTHOR]

The object of this study is a selective average of the dangerous parameters of the gas environment during the ignition of materials. Theoretical substantiation of the fire detection method based on testing the null hypothesis regarding the current difference of the specified selective averages of an arbitrary dangerous parameter of the gas environment has been performed. In this case, the significance of the current difference with respect to selective averages allows detection of ignition in real-time observation of an arbitrary dangerous parameter of the gas environment. The method makes it possible to set the level of significance for the current difference and at the same time provide for the maximum power of fire detection. Laboratory experiments were conducted to verify the proposed method for detecting ignition based on the current difference of the selective averages of the measured dangerous parameters of the gas environment corresponding to the training and control general population. The results of verification showed that at a given level of significance, the method allows detecting current fires of materials based on significant differences in sample means. It was established that the current difference in the concentration of carbon monoxide during ignition and after ignition of alcohol, paper, wood shavings, and textiles is-0.459 and 8.296,-0.152 and 4.299,-0.027 and 6.9,-0.262 and 2.3, respectively. Current smoke density differences are 0.043 and 0.391, 0.012 and 0.923,-0.139 and-0.235, 0.034 and 0.129 and temperatures are-0.01 and 10.635, 0.53 135 and 2.726, respectively. This means that the current difference is significant and is due not to a random nature but to the appearance of a persistent effect from the ignition of the material. In practice, research results can be used to detect fires in real time in order to prevent them from growing into an uncontrolled fire. [ABSTRACT FROM AUTHOR]

Purpose. To develop an environmentally friendly technology for drilling and blasting operations in quarries that will ensure effective degassing and dust suppression during mass explosions by using a natural humate reagent in internal and external hydro-filling. Methodology. The study used a set of research methods: analytical – to establish the main technical and economic indicators that affect the cost of drilling and blasting operations; technical and economic analysis – to establish the relationship between the cost of operations, air pollution after massive explosions and types of hydro-fillings and concentrations of humate reagent. Findings. The paper presents the results of pilot tests of the effectiveness of applying the humate reagent in the preliminary humidification of blocks and its use in internal and external hydro-filling, which leads to a significant reduction in dust formation and degassing of mass explosions. During the period of production research from 2017 to 2021, the environmental efficiency of the use of internal and external hydro-filling with the use of humate reagent TU U 20.5-43384697-001:2020 was confirmed at the enterprises of the Metinvest Holding: PJSC Inhulets Mining and Processing Plant, Pivnichnyi Mining and Processing Plant, Tsentralnyi Mining and Processing Plant, as well as ArcelorMittal Kryvyi Rih, JSC Pivdennyi Mining and Processing Plant and Rudomain LLC. When using an aqueous solution of humate reagent with a concentration of 3 % in internal and external hydrofilling, the environmental effect involves on average: dust suppression – 54 %; neutralization of carbon monoxide – 62 %; neutralization of nitrogen oxides – 55 %. The results of industrial tests have confirmed scientific hypotheses regarding the processes of binding dust particles in the dust and gas cloud, as well as the effect of neutralizing explosive gases. Originality. Dependences of the concentration of humate reagent in internal and external hydro-filling and binding of dust particles during mass explosions with environmental efficiency in terms of dust and gas suppression were established. Industrial research will allow confirming the scientific hypothesis about the neutralization of CO by a humate reagent in mass explosions, which is based on the Langmuir theory. Practical value. An eco-oriented technology of drilling and blasting operations in quarries has been developed which is based on using humate reagents in internal and external hydro-filling and allows industrial enterprises using massive explosions to reduce dust, carbon and nitrogen oxide emissions. [ABSTRACT FROM AUTHOR]

Methane explosions often occur during the closure process of mine fire zones, during which the concentration of combustible gases such as monoxide and ethylene produced by coal combustion dynamically changes, which changes the risk of methane explosion. Therefore, studying the gas concentration distribution and methane explosion limits during the process of mine closure is of great significance for disaster prevention and control. In this paper, a three-dimensional physical model of gob was built, and the distribution of monoxide and ethylene in the process of fire zone closure was investigated. Further, the explosion limits of methane enriched with CO and C2H4 in the closed fire zone of gob were analyzed. The results indicate that CO and C2H4 would form a small-scale accumulation phenomenon near the fire zone after the closure of the fire zone, and when the fire zone is closed for more than 15 min, the mixed combustible gases in the environment lose their explosiveness. [ABSTRACT FROM AUTHOR]

In most countries energy needs are satisfied using fossil fuels. Fossil fuel combustion involves environmental pollution and greenhouse gas emissions. The effect of the depletion of natural resources and the growing awareness of the need to protect the environment are the reasons that clean energy and alternative energy sources have been significant research issues. One of the most important technologies enabling efficient generation of low-emission energy is the gasification process of synthesis gas production. Syngas is primarily composed of hydrogen and carbon monoxide, but depending on the feedstock, it can also contain smaller concentrations, e.g., of carbon dioxide, methane and nitrogen. Because synthesis gas contains flammable and toxic substances, it may pose hazards to humans and the environment at every stage of gas production, storage, transport or final utilization if released uncontrollably. This paper presents the results of analyses related to hazards created by an uncontrollable release of synthesis gas during storage. A failure of a syngas system may cause damage to other, subsequent technological systems and facilities located in the neighborhood and containing dangerous substances. The problem gains special significance if syngas is stored in many tanks, where a failure of one may result in damage to subsequent tanks due to the so-called domino effect. The conditions in which the domino effect may occur are analyzed and the effect occurrence probability is determined depending on the mutual location of the tanks. [ABSTRACT FROM AUTHOR]

The present study utilized the ab initio atomistic thermodynamics technique to assess the stability of pure carbon dioxide and pure methane on the calcite(10.4) systems. The stability of configurations 0.5 ML-A2, 0.75 ML-A2, and 0.75 ML-A1 in CH4/calcite (10.4) systems was shown to be considerable, but only within a limited range of chemical potential. The 1.0 ML-A1 and 1.0 ML-A2 systems of CH4/calcite (10.4) demonstrated remarkable stability throughout a wide range of chemical potentials. The predominant stable forms for CO2/calcite (10.4) systems are the 1.0 ML-B2 and 1.0 ML-A4 structures. The surface free energy phase diagrams demonstrate that CO2 is more favourable than CH4 for adsorption on the calcite (10.4) surface. Paper type: Short communication paper [ABSTRACT FROM AUTHOR]

Hydrogen from natural gas reforming can be produced efficiently with a high CO2 capture rate. This can be achieved through oxygen-blown autothermal reforming as the core technology, combined with pressure-swing adsorption for hydrogen purification and refrigeration-based tail gas separation for CO2 capture and recirculation of residual hydrogen, carbon monoxide, and methane. The low-temperature tail gas separation section is presented in detail. The main objective of the paper is to study and quantify the exergy efficiency of this separation process in detail. To achieve this, a detailed exergy analysis is conducted. The irreversibilities in 42 different process components are quantified. In order to provide transparent verification of the consistency of exergy calculations, the total irreversibility rate is calculated by two independent approaches: Through the bottom-up approach, all individual irreversibilities are added to obtain the total irreversibility rate. Through the top-down approach, the total irreversibility rate is calculated solely by the exergy flows crossing the control volume boundaries. The consistency is verified as the comparison of results obtained by the two methods shows a relative deviation of 4 · 10 − 7 . The exergy efficiency of the CO2 capture process is calculated, based on two different definitions. Both methods give a baseline exergy efficiency of 58.38%, which indicates a high degree of exergy utilisation in the process. [ABSTRACT FROM AUTHOR]

The green hub‐and‐spoke airline network (GHSAN) is emerging as a dominant feature due to its excellent economic and environmental‐friendly capabilities. However, environmental GHSAN designs still have some concerns, including single pollutant‐domain oversimplification and lack of comprehensive network‐level operation impacts. This paper proposes a multi‐emission‐driven efficient network design approach for GHSAN, utilizing a system, green, and user threefold optimization methodology. The approach includes a multi‐objective optimization model and a two‐layer solving method. The multi‐objective optimization aims at minimizing multiple emissions, including carbon dioxide, carbonic oxide hydrocarbon, and nitric oxide, while also considering transportation system costs and journey user costs. A two‐layer optimization algorithm is adopted to address different scales of optimization. Real‐world results demonstrate that the proposed method mitigates environmental impact and user costs and increases overall airline density in airline networks. The proposed method can have a 16.29% reduction in green‐fold (10 nodes) and a 12.06% decrease in user costs for the user‐fold (10 nodes). As the number of nodes (15, 25, 50 nodes) and hubs (3, 4, 5, 6, 7 hubs) increase, the genetic algorithm (GA) proves to be more efficient and suitable in large‐scale GHSAN. This work is further significant for the long‐term and sustainable development of the future air transport industry. [ABSTRACT FROM AUTHOR]

This paper presents a monitoring system to measure dust, noise, ultraviolet radiation, illuminance, temperature, and humidity and to check the presence of flammable gases—liquefied petroleum gas (LPG), propane, hydrogen, butane, methane, and carbon monoxide. The system is composed of monitoring devices, a server to process data received from the devices and that runs a web application for employers, and a mobile application for workers to check their exposure data. During employee registration, the health history of the worker concerning common diseases and symptoms related to the monitored agents must be informed. This information is analyzed through a set of predefined rules to generate alerts that the company can consider for planning professional activities to minimize exposure to risk agents. The tests presented in this work are focused on verifying the functionalities of the web interface for employee registration, especially regarding the provision of health information, the updating of this information, and the generation of corresponding alerts. At this stage, fictitious employee information was used. The results showed that the system adequately performs the proposed functionalities, and it was concluded that the solution is viable for testing in a work environment in the future stages of development. The innovative features of this study concern the correlation between workers' health history and harmful agents to build suggestions and alerts to guide long-term OSH-related decisions. [ABSTRACT FROM AUTHOR]

This paper discusses the result obtained from the investigation on the performance, emission, and combustion characteristics of multi-cylinder SI engines using ethanol-n butanol-unleaded gasoline blends (EB5, EB10, EB15, and EB20) as fuel. The tests were conducted at 10 Nm and 15 Nm load conditions. The speed varied between 1200 and 2400 rpm. Increased blend percentage increases brake thermal efficiency, and the brake thermal efficiency of 16.7%, 17.8%, 18.3%, and 19.2% are achieved for EB5, EB10, EB15, and EB20, respectively, at 15 Nm and 2400 rpm. The tremendous reduction in hydrocarbon and carbon monoxide emissions is observed with an increase in load and speed conditions with blends. The lowest hydrocarbon and carbon monoxide emissions of 164 ppm and 0.01569%, respectively, are obtained at 15 Nm and 2400 rpm. However, oxides of nitrogen emissions increased in all blends and load conditions. The EB20 blend produced the highest in-cylinder pressure of 27.2 bar at 15 Nm and 2400 rpm. [ABSTRACT FROM AUTHOR]

This paper investigated the effects of exhaust gas recirculation (EGR) on homogeneous charge compression ignition (HCCI) combustion in internal combustion engines. The exhaust valve closing (EVC) timings were scanned to obtain a set of baseline operating points for HCCI, and the coupling control of the internal and external EGR was explored. The results indicate that external EGR delays HCCI ignition timing and slows down the combustion speed. As the internal EGR rate increases, the maximum external EGR ratio that can be tolerated decreases. For HCCI detonation operating points with low internal EGR rates, the addition of up to 10% of external EGR can control the pressure rise rate peak to less than 10 bar/°CA, resulting in reduced fuel consumption and increased indicated mean effective pressure (IMEP). However, for HCCI operating points with high internal EGR rates, the effect of external EGR is mainly observed in the control of the pressure rise rate, with limited increase in IMEP. Additionally, an increasing external EGR rate leads to a significant decrease in nitrogen oxide (NOx) emissions, while carbon monoxide (CO) and hydrocarbon (HC) emissions slightly increase before engine misfire occurs. These findings suggest that the coupling control of internal and external EGR should be explored further, particularly in relation to reducing the negative valve overlap (NVO) angle and improving combustion efficiency. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) and cyanide poisoning are frequent causes of morbidity and mortality in cases of house and industrial fires. The 14th edition of guidelines from the Undersea and Hyperbaric Medical Society does not recommend hyperbaric oxygen (HBO2) treatment in those patients who have suffered a cardiac arrest and had to receive cardiopulmonary resuscitation [1]. In this paper, we describe the case of a 31-year-old patient who received HBO treatment in the setting of cardiac arrest and survived. [ABSTRACT FROM AUTHOR]

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

This study employs a combination of theoretical analysis, Similarity simulation, and computational fluid dynamics (CFD) to examine the airflow caused by the stack effect under different leakage conditions in high-rise buildings and the transport of fire smoke. Building on previous research, we quantify the leakage area using a formula and classify it into two categories, "tight" and "leaky." Based on the analysis results, we conduct a similarity simulation experiment in a small-scale high-rise building experimental platform with a height of 5.2 m to create a certain size of leakage area at the bottom and record carbon monoxide concentration at different locations and times. The obtained result is then compared with the numerical simulation result, and the similarity simulation results match well with the numerical simulation results. The findings demonstrate that increasing the leakage area accelerates the transport of smoke due to the stack effect, particularly at higher floors. This paper also discusses strategies to impede smoke diffusion, providing valuable references for the safety design of high-rise buildings. [ABSTRACT FROM AUTHOR]

This paper aimed to investigate the Spatial and Temporal Variation of the air quality index (AQI) in the Amman and Zarqa Metropolitan Areas during the period 2016-2022 following the method adopted by the Environmental Protection Agency of the United States of America (EPA). Air quality data for PM10, PM2.5, O3, NO2, SO2, and CO recorded at five monitoring stations were downloaded from the official website of the Jordanian Ministry of Environment. Calculated AQI values were generally between the Good class (AQI <50) and the Moderate class (AQI 50-100) at all stations, the AQI calculations for PM10 demonstrated a noticeable increase during autumnal months, likely due to natural dust. PM2.5 demonstrated seasonal variation, with higher values in winter months where residents burn fossil fuel for heating. Stabel air in winter due to the cooled land surface, and the weak natural air mix and ventilation contribute to the deterioration of air quality. Calculated individual AQI for SO2 and NO2 reveals that all extent of the study area falls in the Good AQI class. Similarly, CO and ozone-based AQI values fluctuate within the "Good" class, with occasional episodes of compromised air quality at specific stations. [ABSTRACT FROM AUTHOR]

This paper proposes a structural decomposition analysis (SDA) augmented with cross-country atmospheric circulation and uncovers that changes in carbon monoxide (CO) levels are driven by atmospheric flows way more than by any of the traditional SDA components. Applied to a five-region model, our results show, among others, that South Korea has certainly been able to reduce the CO emissions in its own territory by 0.8Tg over 1990–2014 but up to 10.6Tg of CO flowing to its borders came from its upwind neighbor China. That amount was primarily driven by activities satisfying the growth of China's domestic demand, although changes in foreign demand and in the technology effect were not negligible. By quantifying the role of upwind countries in air pollution changes, our methodology allows us to identify more comprehensive global emission abatement policies than the consumer- or producer-focused approaches currently used. [ABSTRACT FROM AUTHOR]

Over the past two decades, following the discovery of the important biological roles of carbon monoxide (CO), metal carbonyl complexes have been intensively studied as CO-releasing molecules (CORMs) for therapeutic applications. To improve the properties of "bare" low molecular weight CORMs, attention has been drawn to conjugating CORMs with macromolecular and inorganic scaffolds to produce CO-releasing materials (CORMAs) capable of storing and delivering large payloads of the gasotransmitter. A significant obstacle is to obtain CORMAs that retain the beneficial features of the parent CORMs. In the present work, a crystalline metal–organic framework (MOF) formulated as Mo(CO)3(4,4′-bipyridine)3/2 (Mobpy), with a structure based on Mo(CO)3 metallic nodes and bipyridine linkers, has been prepared in near quantitative yield by a straightforward reflux method, and found to exhibit CO-release properties that mimic those typically observed for molybdenum carbonyl CORMs. Mobpy was characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), FT-IR, FT-Raman and diffuse reflectance (DR) UV-vis spectroscopies, and 13C{1H} cross-polarization (CP) magic-angle spinning (MAS) NMR. The release of CO from Mobpy was studied by the deoxy-myoglobin (deoxy-Mb)/carbonmonoxy-myoglobin (MbCO) UV-vis assay. Mobpy liberates CO upon contact with a physiological buffer in the dark, leading to a maximum released amount of 1.3–1.5 mmol g−1, after 1.5 h at 37 °C, with half-lives of 0.5–1.0 h (time to transfer 0.5 equiv. of CO to Mb). In the solid-state and under open air, Mobpy undergoes complete decarbonylation over a period of 42 days, corresponding to a theoretical CO-release of 7.25 mmol g−1. [ABSTRACT FROM AUTHOR]

Homogeneous charge-induced ignition (HCII), which uses trace diesel to induce the ignition of gasoline pre-mixture, is characterized by rapid lean combustion and is generally regarded as efficient, clean and controllable. In this paper, a conventional diesel engine has been modified to run all cylinders in HCII mode and the influence of diesel injection pressure (DIP) on overall engine performance was experimentally studied. Results show that the increase of DIP can expand the ignition area of gasoline and enlarge the premixed combustion ratio of diesel, thus promoting rapid combustion and improving brake thermal efficiency. The increase of DIP is beneficial to the control of ignition time and combustion phase, thus reducing the cyclic fluctuation. The increase of DIP can effectively reduce the emission of total hydrocarbon, carbon monoxide and smoke, while the emission of nitrogen oxides (NOx) is insensitive to the change of DIP, so the trade-off relationship between NOx and smoke disappears. However, excessive DIP will still lead to increased combustion noise, and deteriorated combustion quality caused by too less inducing diesel, etc. The appropriate value is about 1000 bar within the test range. [ABSTRACT FROM AUTHOR]

In order to study the cruise safety of aircraft under high altitude and low pressure, the combustion characteristics of protective cover and insulation layer of waxy aviation cable FXL under normal pressure and low pressure are studied in this paper. The minimum ignition time (TTI), the maximum radiation temperature, the flue gas density and the mass loss rate of the protective cover and insulation layer of the waxy FXL aviation cable under 96 kPa and 61 kPa were studied. It is found that the minimum radiation temperature and TTI of the cable at 61 kPa are slightly higher than those at 96 kPa, but the activation energy is basically not affected by the air pressure. The smoke density and smoke composition under 96 kPa and 61 kPa were further studied, and it was found that the smoke density of the cable under 61 kPa sheath and insulation layer was lower than that under 96 kPa. The oxygen, carbon dioxide and carbon monoxide components in the flue gas were studied. It was found that the O2 concentration of 96 kPa and 61 kPa cable protective sleeve and insulation layer decreased steadily at first and then increased. The change trend of CO2 concentration was opposite, and the CO concentration showed a double-peak phenomenon. In addition, the mass loss rate (MLR) at different O2 concentrations increases linearly with the increase in O2 concentration. This work helps to understand the difference of combustion characteristics between 96 and 61 kPa, and provides a reference for improving civil aviation safety performance. [ABSTRACT FROM AUTHOR]

A simple and recyclable homogeneous catalytic system for the hydrogenation of carbon monoxide to methanol was established. The reaction is catalyzed by a molecular manganese complex using a high-boiling alcohol as the solvent for catalyst immobilization. The CO hydrogenation is assisted by the product itself and the solvent through the formation of a methyl or dodecyl formate ester intermediate mediated by catalytic amounts of NaOMe as the base. This allows the catalytic formation of methanol in alcohols combined with facile product separation and catalyst recycling via distillation. Initial turnover frequencies (TOF) of 2250 h−1 were reached under optimized conditions in 1-dodecanol/methanol as the reaction medium (T = 160 °C, p(H2/CO) = 80/10 bar). The performance was stabilized in batch-wise recycling over 6 runs achieving a total turnover number (TTON) of >12 000 corresponding to an enhancement of more than five times compared to single batch operation under identical conditions. Minimal leaching of the components of the organometallic catalyst was observed during distillative product separation and catalyst activity could be fully restored by re-addition of the base NaOMe. [ABSTRACT FROM AUTHOR]

Countries are obliged by international regulations to conduct annual pollutant emissions inventories. Road transport is one of the sectors for which an inventory of pollutant emissions is carried out. Determining pollutant emissions from road transport is possible only by modeling these emissions – that is why unified emission models are used. In this work, the COPERT and HBEFA INFRAS software are used to determine pollutant emissions characteristics for various vehicle traffic models. The article presents the principles of modeling pollutant emissions from road vehicles. The rules for qualifying road vehicles into elementary and cumulative categories have been systematized. Models of road vehicle traffic and ways of taking them into account in modeling pollutant emissions are presented. The following emissions of pollutants harmful to the health and life of living organisms are considered: carbon monoxide, non-methane volatile organic compounds, nitrogen oxides and total suspended particles. The trends of the national annual emissions of the tested pollutants for the years 2000–2020 and the results of simulation tests of pollutant emissions models are presented. [ABSTRACT FROM AUTHOR]