Residuo de Elaeis guineensis (Arecaceae) como absorbente de combustibles para aplicación pasiva en ingeniería contra incendios / Elaeis guineensis (Arecaceae) residue as a fuel sorbent for passive application in fire-fighting engineering

Resumen Introducción: Los vertidos de líquidos inflamables pueden producir accidentes graves, principalmente en plantas industriales y en carretera. Para prevenir la dispersión de derrames, se utilizan diversas formas de recolecta, como la absorción con sólidos porosos. Residuos agroindustriales pueden ser aprovechados como materiales sorbentes de líquidos inflamables. Objetivo: Determinar la capacidad de absorción de las biomasas residuales del pedúnculo de la palma aceitera (Elaeis guineensis) y del endocarpio del fruto de coyol (Acrocomia sp.) para cuatro líquidos orgánicos inflamables. Métodos: Las biomasas residuales de E. guineensis y de Acrocomia sp. se evaluaron como sorbentes para combustibles derramados (diésel, queroseno de aviación, queroseno comercial y gasolina). Se midió la cantidad de líquido absorbida por las biomasas a 24 ºC durante una semana, y su cinética de desorción a 50 ºC, usando balanzas de secado. Resultados: La propiedad sorbente del material de Acrocomia sp. no fue satisfactoria, comparada con el pedúnculo de E. guineensis, debido a diferencias en arquitectura residual del material orgánico. Esta última biomasa muestra una capacidad de absorción para los combustibles de 2.4 ± 0.2 cm3 g-1 a 24 ºC. La diatomita absorbe mayor cantidad de los combustibles estudiados, pero la difusión de estos fluidos a 50 ºC por la matriz mineral es solo 0.26 ± 0.09 veces lo observado para el material de E. guineensis, como resultado del mayor grado de tortuosidad de los poros de la diatomita. Conclusiones: El pedúnculo de palma aceitera (E. guineensis) mostró un adecuado potencial desempeño para la aplicación pasiva en la mitigación de los riesgos de incendio, con respecto a la diatomita. El endocarpio del fruto de Acrocomia sp. no resultó útil para esta operación de recuperación.

Abstract Introduction: Spills of flammable liquids can lead to serious accidents, mainly in industrial plants and on roads. To prevent the spread of spills, various forms of collection are used, such as absorption with porous solids. Agroindustrial waste can be used as sorbent materials for flammable liquids. Objective: To determine the sorption capacity of the residual empty-fruit bunch of oil-palm (Elaeis guineensis) and the macaw palm (Acrocomia sp.) nutshell for four organic flammable liquids. Methods: The residual biomasses of E. guineensis and Acrocomia sp. were assessed as sorbents for spilled fuels (diesel, jet fuel, commercial kerosene, and gasoline). Volumetric measurement of liquid-fuel absorption at 24 ºC was taken during a week. Desorption was measured at 50 ºC as the drying kinetics, by using moisture scales. Results: The sorption capacity of the Acrocomia sp. material was not satisfactory, compared to the E. guineensis residual material, due to differences in the residual architecture of the organic material. This last can absorb 2.4 ± 0.2 cm3 g-1 at 24 ºC, during a one-week period. Diatomite absorbs greater quantities of the organic liquids but, the fluids diffusion at 50 ºC is 0.26 ± 0.09 times more slowly in the mineral matrix, because of the greater pore tortuosity in this mineral matrix. Conclusions: The oil-palm empty fruit bunch of E. guineensis, showed lesser but adequate performance than the sorbing behavior for fire hazard mitigation of diatomite. The nutshell of macaw palm (Acrocomia sp.) did not prove to be useful for this recovery operation.

Predict the characteristics of the DI engine with various injection timings by Glycine max oil biofuel using artificial neural networks.

Glycine max oil biofuel (GMOB) is a product of the transesterification of soybean oil. It contains a substantial amount of thermal energy. In this study, the result of varying fuel injection timings on the performance, ignition, and exhaust parameters of a research engine with single-cylinder, four-stroke with direct injection (DI) diesel was experimentally investigated and optimised using artificial neural networks (ANN). The results demonstrated that a 20% fuel blend with 24.5° before top dead centre (b TDC) decreased brake thermal efficiency (BTE), NOx emissions, and exhaust cylinder temperature but improved fuel consumption, carbon dioxide emissions (CDE), and smoke emissions. With 26.5° b TDC, the BTE was found to be approximately 5.0% higher while the fuel consumption was approximately 2.0% lower than with the original injection timing of 24.5° b TDC. At 26.5° b TDC, the NOx emission was approximately 8.6% higher, and the smoke emission was approximately 4.07% lower than at the original injection timing (24.5° b TDC).

Characterization of on-road nitrogen oxides and black carbon emissions from high emitters of heavy-duty diesel vehicles in China.

Heavy-duty diesel vehicles (HDDVs) significantly contribute to atmospheric nitrogen oxides (NOX) and black carbon (BC), with high emitters within the HDDV fleet impacting the total emissions. However, emission patterns and contributions of high emitters are rarely explored from a fleet-perspective. We investigated NOX and BC emission factors (EFs) from 1925 HDDVs in Shenzhen by the plume-chasing method, and found that the fleet-average EFs decreased with stricter emission standards. Unexpectedly, the average NOX EF for the China IV fleet was comparable with that for the China III fleet due to possible ineffective aftertreatment in high-emitter sectors of China IV HDDVs. Decreasing trend in average NOX EF since 2017 reflected the effective emission controls by the implementation of China V standard. Besides, semi-trailer tractors exhibited a higher incidence of NOX over-emissions, whereas BC high emitters were more pronounced in box trucks. Total NOX and BC emissions from HDDVs in Shenzhen were revisited, reaching 54.0 and 1.1 Gg·yr-1, with updated NOX EF correcting a 26.2 % underestimation in national guidelines. Notably, eliminating high emitters yields greater emission reduction benefits than merely retiring old HDDVs, with BC reduction outpacing NOX. This study provides new insights into the implementation of targeted emission reduction measures for HDDVs.

Enhancing residential energy access with optimized stand-alone hybrid solar-diesel-battery systems in Buea, Cameroon.

This study examined the optimal size of an autonomous hybrid renewable energy system (HRES) for a residential application in Buea, located in the southwest region of Cameroon. Two hybrid systems, PV-Battery and PV-Battery-Diesel, have been evaluated in order to determine which was the better option. The goal of this research was to propose a dependable, low-cost power source as an alternative to the unreliable and highly unstable electricity grid in Buea. The decision criterion for the proposed HRES was the cost of energy (COE), while the system's dependability constraint was the loss of power supply probability (LPSP). The crayfish optimization algorithm (COA) was used to optimize the component sizes of the proposed HRES, and the results were contrasted to those obtained from the whale optimization algorithm (WOA), sine cosine algorithm (SCA), and grasshopper optimization algorithm (GOA). The MATLAB software was used to model the components, criteria, and constraints of this single-objective optimization problem. The results obtained after simulation for LPSP of less than 1% showed that the COA algorithm outperformed the other three techniques, regardless of the configuration. Indeed, the COE obtained using the COA algorithm was 0.06%, 0.12%, and 1% lower than the COE provided by the WOA, SCA, and GOA algorithms, respectively, for the PV-Battery configuration. Likewise, for the PV-Battery-Diesel configuration, the COE obtained using the COA algorithm was 0.065%, 0.13%, and 0.39% lower than the COE provided by the WOA, SCA, and GOA algorithms, respectively. A comparative analysis of the outcomes obtained for the two configurations indicated that the PV-Battery-Diesel configuration exhibited a COE that was 4.32% lower in comparison to the PV-Battery configuration. Finally, the impact of the LPSP reduction on the COE was assessed in the PV-Battery-Diesel configuration. The decrease in LPSP resulted in an increase in COE owing to the nominal capacity of the diesel generator.

Diesel removal in non-aqueous phase by fibres from Calotropis procera: kinetic, isothermal and sorption potential evaluation.

Calotropis procera fibres have been proposed for free-phase diesel removal in case of spillage into groundwater. For this, characterizations were carried out using Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FEG-SEM), wettability and contact angle measurements. Sorption oil capacity, kinetic, isothermal and recycling behaviour were evaluated. For initial optimization of the oil sorption capacity, an experimental design (DOE) was applied, with the optimized condition being 60 g L-1 of diesel in water and 0.01 g of fibre. Then, the results clearly indicated that the fibres have a hydrophobic and oleophilic character, quickly reaching more than 71.43 g g-1 of diesel sorption, according to the adjustment (R² > 0.99) of the pseudo-second order and Langmuir models, governed by absorption mechanisms. It should also be noted that at the end of 8 reuse cycles, the fibre presented a total accumulated sorption capacity of about 252.6 g g-1 of diesel. Furthermore, a laboratory-scale experiment was carried out to remove diesel from groundwater in gas station areas, the fibre removed 98.55% to 99.97% of removal efficiencies were achieved of the free phase over time. Therefore, the material demonstrates excellent characteristics for removing diesel spills in groundwater due to its fast, high and stable removal capacity.

Ammonia energy fraction effect on the combustion and reduced NOX emission of ammonia/diesel dual fuel.

With stringent regulations of internal combustion engine on reducing CO2 emission, ammonia has been used as an alternative fuel. Investigating how engine-related performance is affected by partial ammonia replacement of diesel fuel is essential for understanding the combustion. Therefore, in this study, a three-dimensional numerical simulation model is developed for the burning of two fuels of diesel and ammonia based on relevant parameters (i.e., compression ratio, load, ammonia energy fraction, etc.) in a lab-made diesel engine. The consequences of load and compression proportion on combustion and pollutant emissions are investigated for ammonia energy fractions between 50% and 90%. When the ammonia portion rises, the increased ammonia equivalent ratio causes ammonia to move away from the dilute combustion boundary and accelerates the combustion rate of ammonia. An increase in compression ratio significantly increases the specified thermal performance and combustion efficacy. When the compression ratio is 16, as the ammonia energy fractions increases, due to the increase in the proportion of ammonia, that is, the proportion of nitrogen atoms increases, more NOx is generated during the combustion process. When the ammonia substitution rate is 90%, as the compression ratio increases, the cylinder pressure and temperature increase. The combustion efficiency of ammonia increases, generating more NOx and NOx emissions can reach 0.66 mg/m3. At a compression ratio of 18, the NOx emissions can reach 1.59 mg/m3. However, under medium and low load conditions, as the ammonia fraction increases, the total energy of fuel decreases, and the combustion efficiency of ammonia decreases, resulting in a decrease in the heat released during combustion and a decrease in NOx emissions. When the ammonia substitution rate is 90% and the load is 25%, NOx emissions reach 0.1 mg/m3. This research provides theoretical suggestions for the profitable and use ammonia fuel in internal combustion engines in a clean manner.

Co,Ce nanoparticles supported on stacked wire mesh cartridges. Activity and stability in diesel soot combustion.

In this work, Co3O4 nanoparticles were successfully synthesized by precipitating a precursor salt solution in the form of microdroplets generated by a nebulizer, as an efficient, fast and low-cost approach. After drying and calcination, synthesized particles were deposited on stacked wire mesh monoliths by immersing the structures in a suspension containing synthesized Co3O4 particles and commercial ceria nanoparticles as a binder. These structured catalysts were evaluated for the combustion of diesel soot which constitutes a crucial step in the regeneration of catalytic particulate filters (CDPFs). Thermal and mechanical stability of Co,Ce washcoated monoliths were investigated. For this, successive catalytic evaluations of the structured system, with intermediate treatments at 900 °C (accelerated aging), were carried out indicating a very good activity and stability of the catalysts developed. Adherence tests showed good adhesion of the catalytic layer to the metallic substrate. Fresh and aged catalysts were fully characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), Laser Raman Spectroscopy (LRS) and Temperature-Programmed Reduction (TPR). It was found that the catalytic coating resulted composed of nanometric CeO2 and Co3O4 along with chromium, iron and manganese oxides coming from the migration of the metallic substrate, in the catalytic cartridge calcined at 600 °C. Despite after calcination at 900 °C spinels of Co, Fe, Cr and Mn were observed, these oxides did not significantly affected the catalytic activity. Although this aging treatment at 900 °C was severe and is not expected under real conditions, it highlights the potential application of the catalytic metallic cartridges here developed.

Mechanism underlying the role of integrin α3ß1 in adhesive dysfunction between thyroid cells induced by diesel engine exhaust particles.

The role and mechanisms of DEP exposure on thyroid injury are not yet clear. This study explores thyroid damage induced by in vivo DEP exposure using a mouse model. This study has observed alterations in thyroid follicular architecture, including rupture, colloid overflow, and the formation of voids. Additionally, there was a significant decrease in the expression levels of proteins involved in thyroid hormone synthesis, such as thyroid peroxidase and thyroglobulin, their trend of change is consistent with the damage to the thyroid structure. Serum levels of triiodothyronine and tetraiodothyronine were raise. However, the decrease in TSH expression suggests that the function of the HPT axis is unaffected. To delve deeper into the intrinsic mechanisms of thyroid injury, we performed KEGG pathway enrichment analysis, which revealed notable alterations in the cell adhesion signaling pathway. Our immunofluorescence results show that DEP exposure impairs thyroid adhesion, and integrin α3ß1 plays an important role. CD151 binds to α3ß1, promoting multimolecular complex formation and activating adhesion-dependent small GTPases. Our in vitro model has confirmed the pivotal role of integrin α3ß1 in thyroid cell adhesion, which may be mediated by the CD151/α3ß1/Rac1 pathway. In summary, exposure to DEP disrupts the structure and function of the thyroid, a process that likely involves the regulation of cell adhesion through the CD151/α3ß1/Rac1 pathway, leading to glandular damage.

Recent Progress in Creep-Resistant Aluminum Alloys for Diesel Engine Applications: A Review.

Diesel engines in heavy-duty vehicles are predicted to maintain a stable presence in the future due to the difficulty of electrifying heavy trucks, mine equipment, and railway cars. This trend encourages the effort to develop new aluminum alloy systems with improved performance at diesel engine conditions of elevated temperature and stress combinations to reduce vehicle weight and, consequently, CO2 emissions. Aluminum alloys need to provide adequate creep resistance at ~300 °C and room-temperature tensile properties better than the current commercial aluminum alloys used for powertrain applications. The studies for improving creep resistance for aluminum casting alloys indicate that their high-temperature stability depends on the formation of high-density uniform dispersoids with low solid solubility and low diffusivity in aluminum. This review summarizes three generations of diesel engine aluminum alloys and focuses on recent work on the third-generation dispersoid-strengthened alloys. Additionally, new trends in developing creep resistance through the development of alloy systems other than Al-Si-based alloys, the optimization of manufacturing processes, and the use of thermal barrier coatings and composites are discussed. New progress on concepts regarding the thermal stability of rapidly solidified and nano-structured alloys and on creep-resistant alloy design via machine learning-based algorithms is also presented.

Quantitative response of the spatial distribution of diesel oil to freezing and thawing temperatures in groundwater.

The mobilization and redistribution of organic contaminants in groundwater is the basis and key to explore its dynamic evolution and appropriate remediation. The naturally occurring diametrical temperature gradient during freezing and thawing cycle leads to distinct behaviors of organic contaminants in groundwater. In this study, the pore-scale distribution of diesel oil in the porous media was quantitatively divided into capillary fluid state (CFS) and free fluid state (FFS) based on multiphase flow dynamics, employing low-field nuclear magnetic resonance (LF-NMR) technology. The pore-scale distribution of diesel oil depends not only on the freezing and thawing cycle but also on the temperature gradient according to LF-NMR results. The content of diesel oil in the CFS generally increases with a positive temperature gradient (e.g. freezing) compared to a negative temperature gradient (e.g. thawing), while the content of diesel oil in the FFS generally decreases. This dependence of the temperature gradient on pore-scale distribution of the diesel oil is positively correlated with the particle size of the porous medium. Furthermore, the pore-scale distribution of the diesel oil during the freezing and thawing cycle is influenced by the kinematic viscosity of the diesel oil. There is an exponential relationship between the diesel oil content and the kinematic viscosity, independent of the freezing or thawing process. During the freezing process, the diesel oil migrates from FFS to CFS, while this migration is reversed during the thawing process. The reverse migration of the diesel oil between the freezing and thawing processes leads to a spatial redistribution of the diesel oil, which is controlled by both the fluid energy and the capillary force. The present work provide meaningful guidance for the remediation of groundwater contamination in cold regions.

Catalytic activity of Zr/CeO2-Al2O3 catalyst for diesel soot oxidation: synthesis, characterization, and performance evaluation.

Diesel soot is a significant contributor to air pollution. Soot particles present in diesel engine exhaust have a negative impact on the environment and human health. Diesel oxidation catalysts (DOCs) and diesel particulate filters (DPFs) currently use noble metal-based catalysts for soot oxidation. Due to the use of noble metals in the catalyst, the cost of diesel after-treatment systems is steadily rising. As a result, diesel vehicles have become commercially less viable than gasoline vehicles and electronic vehicles. The study focuses on an alternative diesel oxidation catalyst with efficiency similar to that of a noble metal catalyst but with a much lower cost. CeO2-Al2O3 catalysts are known for their oxygen storage capacity and high redox activity, making them suitable for soot oxidation. Adding Zr to these catalysts has been shown to influence their structural and chemical properties, significantly affecting their catalytic behavior. Therefore, the current study is focused on using Zr/CeO2-Al2O3 as a substitute for noble metal-based catalysts to enhance its performance for diesel soot oxidation in automotive exhaust. Evaporation-induced self-assembly (EISA) was used to prepare 1, 3, and 5 weight (wt) % Zr supported mesoporous CeO2-Al2O3 catalysts. Morphological, structural, and physicochemical properties of the synthesized catalysts were examined using Brunauer-Emmett-Teller (BET) absolute isotherm, Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Temperature programmed reduction (TPR), and Temperature-programmed desorption of ammonia (NH3-TPD). XRD, BET, and SEM data confirmed that the catalysts were mesoporous and low-crystalline with a high surface area. The soot oxidation activity of the catalysts was evaluated using a thermogravimetric analysis (TGA) technique. The loose contacts soot oxidation activity test suggested that 50% oxidation of soot occurred at 390 °C in the absence of a catalyst. T50 of CeO2-Al2O3 catalyzed soot oxidation was 296 °C. Adding Zr to the catalyst significantly improved catalytic activity for diesel soot oxidation. We observed a further drastic change in T50 of soot over 1, 3, and 5% Zr/CeO2-Al2O3, which were 220 °C, 210 °C, and 193 °C, respectively. According to these results, incorporating Zr into the CeO2-Al2O3 catalyst significantly improved the oxidation process of soot.

Analysis of a CRDI diesel engine powered by ternary fuel blends (diesel, biodiesel, and pentanol) doped with alumina nano-additives.

Environmental constraints associated with fossil fuels have driven researchers to find a novel, potential and environmentally benign alternative fuel. Biodiesel, vegetable oil, and alcohol have gained rapid momentum thanks to their renewable nature and comparable energy contents in recent years. Accordingly, a Ternary fuel blend is prepared comprising three fuels namely diesel, biodiesel, and pentanol. Waste cooking oil was identified as the source for biodiesel and Pentanol was chosen among various alcohol alternatives due to improved energy density, reduced toxicity. These are endorsed to the enhancement in surface area-volume ratio of nano additives which boosts the catalytic combustion activity and also causing lesser fuel to take part in combustion for maintaining a constant engine speed. The experimentation is done with ternaryfuel blends with varying pentanol and biodiesel concentrations of diesel, biodiesel and pentanol). Upon experimentation, it was observed that, ternary fuel blend 'TF' comprising 70% diesel, 20% biodiesel and 10% pentanol, yielded best performance and was used for doping of Alumina oxide (Al2O3) nano additives. The Al2O3 nanoparticles were doped with ternary blends at fractions of 10 ppm, 20 ppm, and 30 ppm. It was observed that 20 ppm Al2O3 nanoparticle blended TF blend improved BTE and lowered BSFC by about 12.01% and 22.57% respectively. The performance tremendously along with lowered the CO emission by 49.21%, HC emission by 18.91% and smoke opacity by 9.02%.

Characterization of Diesel Degrading Indigenous Bacterial Strains, Acinetobacter pittii and Pseudomonas aeruginosa, Isolated from Oil Contaminated Soils.

In this study, 13 diesel degrading bacteria were isolated from the oil contaminated soils and the promising strains identified as Acinetobacter pittii ED1 and Pseudomonas aeruginosa BN were evaluated for their diesel degrading capabilities. These strains degraded the diesel optimally at 30 °C, pH 7.0 and 1% diesel concentration. Both the strains produced biofilm at 1% diesel concentration indicating their ability to tolerate diesel induced abiotic stress. Gravimetric analysis of the spent medium after 7 days of incubation showed that A. pittii ED1 and P. aeruginosa BN degraded 68.61% and 76% diesel, respectively, while biodegradation reached more than 90% after 21 days. Fourier Transform Infrared (FTIR) analysis of the degraded diesel showed 1636.67 cm-1 (C=C stretch, N-H bond) peak corresponding to alkenes and primary amines, while GC-TOF-MS analysis showed decline in hydrocarbon intensities after 7 days of incubation. The present study revealed that newly isolated A. pittii ED1 and P. aeruginosa BN were able to degrade diesel hydrocarbons (C11-C18, and C19-C24) efficiently and have potential for bioremediation of the oil-contaminated sites. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-024-01317-3.

Antifoams in non-aqueous diesel fuels: Thin liquid film dynamics and antifoam mechanisms.

HypothesisFoaming in diesel fuels is not well understood and leads to operational challenges. To combat deleterious effects of foaming, diesel formulations can include additives called antifoams. Existing antifoams, unfortunately, are inherently ash-generating when combusted, with unknown environmental impacts. They are prohibited in certain countries, so identifying effective alternative ash-free antifoam chemistries is needed. ExperimentsWe conduct systematic characterization of foam stabilization and antifoaming mechanisms in diesel for two different antifoams (silicone-containing & ashless chemistries). Employing a custom technique combining single-bubble/single-antifoam-droplet manipulation with white light interferometry, we also obtain mechanistic insights into foam stability and antifoam dynamics. ResultsCoalescence times from both bulk foam and single bubble experiments confirm ashless antifoams are effective at reducing foaming, demonstrating the potential of ashless antifoams. Further, we perform single-antifoam-droplet experiments and obtain direct experimental evidence revealing the elusive antifoaming mechanisms. Interestingly, the silicone-containing and ashless antifoams seemingly function via two different mechanisms: spreading and dewetting respectively. This surprising finding refutes conventional wisdom that spreading is likely the only antifoam mechanism in diesels. These results and the reported experimental framework significantly enhance the scientific understanding of non-aqueous foams and will accelerate the engineering of alternative antifoam chemistries for non-aqueous systems.

Evaluation of NOx and PN Emission in Relation to Actuator Control.

This study aimed to investigate the interrelationships between key harmful emission components, nitrogen oxides (NOx), and particulate numbers (PNs) in diesel engine exhaust and the control actuators of diesel engines. This research involved conducting a series of experiments under fixed parameters within an engine brake laboratory environment to elucidate these correlations. The objectives of this study were to conduct a comprehensive review of the relevant emissions technology literature and a comparative assessment of particle measurement methods based on dilution ratios and develop innovative aerosol preparation principles tailored to condensation particle measurement. Additionally, this research involved designing and implementing an aerosol preparation unit based on the newly developed principles, along with the creation of test cell control programs using the AVL PUMA Open TST editor interface and Visual Basic. Furthermore, this study was concerned with conducting evaluations of fixed-parameter engine dynamometer tests to explore the functional relationships between the emission of 10/23 nm particles, NOx emissions, common rail pressure variations, and exhaust gas recirculation levels. This study aimed to enhance the understanding of diesel engine emissions dynamics and contribute valuable insights for developing more efficient and environmentally friendly engine control strategies.

Similar experimental study on diffusion and distribution of diesel exhaust in confined space of a coal mine.

In the confined space of the underground coal mine, which is dominated by transportation lanes, explosion-proof diesel-powered trackless rubber-wheeled vehicles are becoming the main transportation equipment, and the exhaust gas produced by them is hazardous to the health of workers and pollutes the underground environment. In this experiment, a similar test platform is built to study the effects of wind speed, vehicle speed, and different wind directions on the diffusion characteristics of exhaust gas. In this paper, CO and SO2 are mainly studied. The results show that the diffusion of CO and SO2 gas is similar and the maximum SO2 concentration only accounts for 11.4% of the CO concentration. Exhaust gas is better diluted by increasing the wind speed and vehicle speed, respectively. Downwind is affected by the reverse wind flow and diffuses to the driver's position, which is easy to cause occupational diseases. When the wind is a headwind, the exhaust gases spread upwards and make a circumvention movement, gathering at the top. When the wind speed and vehicle speed are both 0.6 m/s, the CO concentration corresponds to the change trend of the Lorentz function when the wind is downwind and the CO concentration corresponds to the change trend of the BiDoseResp function when the wind is headwind. The study of exhaust gas diffusion characteristics is of great significance for the subsequent purification of the air in the restricted mine space and the protection of the workers' occupational health.

Simultaneous bioremediation of diesel-contaminated soil and water ecosystems using mixed culture of Acinetobacter baumannii IITG19 and Providencia vermicola IITG20.

Diesel degradation and bacterial growth were investigated in soil, marine water, and freshwater ecosystems using Acinetobacter baumannii IITG19, Providencia vermicola IITG20, and their mixed culture. Both bacteria were found to be effective in all three ecosystems, with the best degradation occurring in freshwater. Acinetobacter baumannii IITG19 showed higher degradation (59%, 62%, and 76%) than Providencia vermicola IITG20 (31%, 57%, and 67%) in soil, marine water, and freshwater, respectively. Alkanes showed higher degradation than naphthenes and aromatics for both strains. The mixed culture showed higher diesel degradation efficiency than individual strains in all ecosystems. The overall degradation was similar in soil and marine water (66%), while freshwater showed the highest degradation of 81%. In the presence of the mixed culture, the degradation of alkanes was more than 90%. Bacterial growth was highest in freshwater and lowest in soil for both bacteria and the mixed culture. Metabolite analysis confirmed alcoholic degradation for alkanes and cyclo-alcoholic degradation for naphthenes. The degradation rate for mixed culture was higher than that of both the individual strains. The mixed culture had highest degradation rate constant in freshwater at 0.11 day-1 followed by that in marine ecosystem at 0.078 day-1. The rate constant was lowest for soil ecosystem at 0.066 day-1. Thus the mixed culture showed effectiveness in all three ecosystems, with its highest effectiveness observed in the freshwater ecosystem.

Cardiotoxicity Induced by Intratracheal Instillation of Diesel Exhaust Particles in Mice, and the Protective Effects of Carnosol: Suppression of Inflammation and Oxidative and Nitrosative Stress via Modulation of NF-κb/MAPKs Signaling Pathways.

BACKGROUND/AIMS: Inhaled particulate air pollution is associated with cardiotoxicity with underlying mechanisms including oxidative stress and inflammation. Carnosol, commonly found in rosemary and sage, is known to possess a broad range of therapeutic properties such as antioxidant, anti-inflammatory and antiapoptotic. However, its cardioprotective effects on diesel exhaust particles (DEPs)-induced toxicity have not been studied yet. Hence, we evaluated the potential ameliorative effects of carnosol on DEPs-induced heart toxicity in mice, and the underlying mechanisms involved. METHODS: Mice were intratracheally instilled with DEPs (1 mg/kg) or saline, and 1 hour prior to instillation they were given intraperitoneally either carnosol (20 mg/kg) or saline. Twenty-four hours after the DEPs instillation, multiple parameters were evaluated in the heart by enzyme-linked immunosorbent assay, colorimetric assay, Comet assay and Western blot technique. RESULTS: Carnosol has significantly reduced the elevation in the plasma levels of lactate hydrogenase and brain natriuretic peptide induced by DEPs. Likewise, the augmented cardiac levels of proinflammatory cytokines, lipid peroxidation, and total nitric oxide in DEPs-treated groups were significantly normalized with the treatment of carnosol. Moreover, carnosol has markedly reduced the heart mitochondrial dysfunction, as well as DNA damage and apoptosis of mice treated with DEPs. Similarly, carnosol significantly reduced the elevated expressions of phosphorylated nuclear factor-кB (NF-кB) and mitogen-activated protein kinases (MAPKs) in the hearts. Furthermore, the treatment with carnosol has restored the decrease in the expression of sirtuin-1 in the hearts of mice exposed to DEPs. CONCLUSION: Carnosol significantly attenuated DEP-induced cardiotoxicity in mice by suppressing inflammation, oxidative stress, DNA damage, and apoptosis, at least partly via mechanisms involving sirtuin-1 activation and the inhibition of NF-кB and MAPKs activation.

Oil-recovery performance of a superhydrophobic sponge-covered disc skimmer.

Frequent oil spill accidents caused by transportation, storage and usage may lead to severe damage on aquatic and ecological environments. Effective methods for rapid oil recovery are urgently in demand. Polyvinyl chloride, hydrophobic nano-SiO2, expanded graphite were separately applied to polyurethane and melamine sponge to fabricate superhydrophobic sponge material. The selected superhydrophobic sponge was introduced to establish sponge - covered disc skimmer. Oil recovery tests of the device were conducted to determine the optimum parameters. The examined operating conditions encompassed sponge thickness, immersion depth, rotational speed, oil slick thickness, operation time. The results showed that the melamine sponge modified by both polyvinyl chloride and hydrophobic nano-SiO2 exhibits super-hydrophobicity with a water contact angle of 150.3°. The absorption capacity for diesel oil can reach 53.89 g/g. The absorption capacity can still achieve 90 % of its initial capacity even after 500 extrusion-absorption separation tests. The results indicate the superiority of the superhydrophobic sponge covered surface in oil recovery over the standard steel surface regardless of the operating conditions. The recovery rate of the device can still achieve 96.4 % of its initial capacity with 95 % efficiency even after 85 h operation. The results suggest the superhydrophobic sponge - covered disc skimmer may have great application perspectives in oil spill recovery.

Diesel exhaust exposure induced squamous metaplasia of corneal epithelium via yes-associated protein activation.

Atmospheric pollution has been demonstrated to be associated with ocular surface diseases characterized by corneal epithelial damage, including impaired barrier function and squamous metaplasia. However, the specific mechanisms underlying the impact of atmospheric pollution on corneal damage are still unknow. To address this gap in knowledge, we conducted a study using a whole-body exposure system to investigate the detrimental effects of traffic-related air pollution, specifically diesel exhaust (DE), on corneal epithelium in C57BL/6 mice over a 28-day period. Following DE exposure, the pathological alterations in corneal epithelium, including significant increase in corneal thickness and epithelial stratification, were observed in mice. Additionally, exposure to DE was also shown to disrupt the barrier functions of corneal epithelium, leading to excessive proliferation of basal cells and even causing squamous metaplasia in corneal epithelium. Further studies have found that the activation of yes-associated protein (YAP), characterized by nuclear translocation, may play a significant role in DE-induced corneal squamous metaplasia. In vitro assays confirmed that DE exposure triggered the YAP/ß-catenin pathway, resulting in squamous metaplasia and destruction of barrier functions. These findings provide the preliminary evidence that YAP activation is one of the mechanisms of the damage to corneal epithelium caused by traffic-related air pollution. These findings contribute to the knowledge base for promoting eye health in the context of atmospheric pollution.