-
Environmental Science & Technology Apr 2024The characteristics of aviation-induced aerosol, its processing, and effects on cirrus clouds and climate are still associated with large uncertainties. Properties of...
The characteristics of aviation-induced aerosol, its processing, and effects on cirrus clouds and climate are still associated with large uncertainties. Properties of aviation-induced aerosol, however, are crucially needed for the assessment of aviation's climate impacts today and in the future. We identified more than 1100 aircraft plume encounters during passenger aircraft flights of the IAGOS-CARIBIC Flying Laboratory from July 2018 to March 2020. The aerosol properties inside aircraft plumes were similar, independent of the altitude (i.e., upper troposphere, tropopause region, and lowermost stratosphere). The exhaust aerosol was found to be mostly externally mixed compared to the internally mixed background aerosol, even at a plume age of 1 to 3 h. No enhancement of accumulation mode particles (diameter >250 nm) could be detected inside the aircraft plumes. Particle number emission indices (EIs) deduced from the observations in aged plumes are in the same range as values reported from engine certifications. This finding, together with the observed external mixing state inside the plumes, indicates that the aviation exhaust aerosol almost remains in its emission state during plume expansion. It also reveals that the particle number EIs used in global models are within the range of the EIs measured in aged plumes.
PubMed: 38588448
DOI: 10.1021/acs.est.3c09728 -
Scientific Reports Apr 2024The implications of adding cerium oxide (CeO) nanoparticles as a fuel additive to a castor oil biodiesel-diesel fuel blend on engine performance and emissions in a...
The implications of adding cerium oxide (CeO) nanoparticles as a fuel additive to a castor oil biodiesel-diesel fuel blend on engine performance and emissions in a single-cylinder four-stroke diesel engine under various speed were examined in the current study. The test fuels used were fossil diesel fuels, B5 blend biodiesel (as 5% biodiesel and 95% diesel), B10 blend biodiesel (as 10% biodiesel and 90% diesel), B15 blend biodiesel (as 15% biodiesel and 85% diesel), B20 blend biodiesel (as 20% biodiesel and 80% diesel), and B25 blend biodiesel (as 25% biodiesel and 75% diesel), with cerium oxide (CeO) nanoparticle additive (75 ppm). The result of the physio-chemical properties of the oil samples was within the limit of the ASTM standard. The addition of CeO nano additive to the biodiesel-diesel blends has demonstrated a significant reduction in emission and increased in engine performance for all biodiesel-diesel blends for the engine operating speed range. From the result B25 have the maximum reduction rate in BSFC and B10 have the minimum reduction rate in BSFC. The average maximum increment of thermal efficiency was 22.2% for B10 with CeO inclusion. CO emission increased as engine speed increased. HC emission was reduced for all blend, with and without CeO nano additions as speed increased. Maximum NO emission was seen at the rated speed of 2700 rpm without nano additive and at 2900 rpm with nano additive. CeO nano additive reduced the soot opacity by 11.56% for all biodiesel-diesel blends for the engine operating speed range. As the objective of this study the results indicates CeO nano additive reduced emissions and improved the performance. So, using sustainable biodiesel-diesel blends made from castor oil with CeO nano additive advisable in ideal operating conditions for diesel engines.
PubMed: 38561406
DOI: 10.1038/s41598-024-58420-0 -
Nanostructured Pr-Rich CePrO Mixed Oxides for Diesel Soot Combustion: Importance of Oxygen Lability.Nanomaterials (Basel, Switzerland) Mar 2024Soot combustion experiments with 5%O/He were conducted using model soot, and four distinct compositions of CePrO oxides of varying nominal cerium compositions (x = 0,...
Soot combustion experiments with 5%O/He were conducted using model soot, and four distinct compositions of CePrO oxides of varying nominal cerium compositions (x = 0, 0.2, 0.3, and 1) were prepared. The catalyst samples were comprehensively characterized using techniques such as XRD, Raman spectroscopy, HR-TEM, N adsorption at -196 °C, XPS, O-TPD, H-TPR, and work function measurements. The Pr-rich compositions, ranging from CePrO to PrO, resulted in a significant increase in the total evolved O amounts and enhanced catalyst reducibility. However, a decrease in the textural properties of the catalysts was noted, which was particularly important for the pure praseodymia under the synthesis route conducted. The catalytic activity was investigated under the two following contact modes of mixing between soot and catalyst: and . The results revealed that the catalytic performance is associated with the surface contact in tight contact mode and with the combination of surface/subsurface/bulk oxygen mobility and the BET surface area in contact mode. Notably, the temperatures estimated at 10% and 50% of the conversion (T and T) parameters were achieved at much lower temperatures than the uncatalyzed soot combustion, even under contact conditions. Specifically, the 50% conversion was achieved at 511 °C and 538 °C for CePrO and CePrO, respectively. While no direct correlation between catalytic activity and work function was observed, a significant relationship emerges between work function values and the formation of oxygen vacancies, whatever the conditions used for these measurements. On the other hand, the ability to generate a high population of oxygen vacancies at low temperatures, rather than the direct activation of gas-phase O, influences the catalytic performance of Pr-doped ceria catalysts, highlighting the importance of surface/subsurface oxygen vacancy generation, which was the parameter that showed a better correlation with the catalytic activity, whatever the soot conversion value or the mode of contact considered.
PubMed: 38535631
DOI: 10.3390/nano14060483 -
Substance Abuse Treatment, Prevention,... Mar 2024Persons with opioid use disorders (OUD) and persons with substance use disorders (SUD) who inject substances have a reduced life expectancy of up to 25 years compared...
BACKGROUND
Persons with opioid use disorders (OUD) and persons with substance use disorders (SUD) who inject substances have a reduced life expectancy of up to 25 years compared with the general population. Chronic liver diseases are a substantial cause of this. Screening strategies based on liver stiffness measurements (LSM) may facilitate early detection, timely intervention, and treatment of liver disease. This study aims to investigate the extent of chronic liver disease measured with transient elastography and the association between LSM and various risk factors, including substance use patterns, hepatitis C virus (HCV) infection, alcohol use, body mass index, age, type 2 diabetes mellitus, and high-density lipoprotein (HDL) cholesterol among people with OUD or with SUD who inject substances.
METHODS
Data was collected from May 2017 to March 2022 in a cohort of 676 persons from Western Norway. The cohort was recruited from two populations: Persons receiving opioid agonist therapy (OAT) (81% of the sample) or persons with SUD injecting substances but not receiving OAT. All participants were assessed at least once with transient elastography. A linear mixed model was performed to assess the impact of risk factors such as HCV infection, alcohol use, lifestyle-associated factors, and substance use on liver stiffness at baseline and over time. Baseline was defined as the time of the first liver stiffness measurement. The results are presented as coefficients (in kilopascal (kPa)) with 95% confidence intervals (CI).
RESULTS
At baseline, 12% (n = 83) of the study sample had LSM suggestive of advanced chronic liver disease (LSM ≥ 10 kPa). Advanced age (1.0 kPa per 10 years increments, 95% CI: 0.68;1.3), at least weekly alcohol use (1.3, 0.47;2.1), HCV infection (1.2, 0.55;1.9), low HDL cholesterol level (1.4, 0.64;2.2), and higher body mass index (0.25 per increasing unit, 0.17;0.32) were all significantly associated with higher LSM at baseline. Compared with persistent chronic HCV infection, a resolved HCV infection predicted a yearly reduction of LSM (-0.73, -1.3;-0.21) from baseline to the following liver stiffness measurement.
CONCLUSIONS
More than one-tenth of the participants in this study had LSM suggestive of advanced chronic liver disease. It underscores the need for addressing HCV infection and reducing lifestyle-related liver risk factors, such as metabolic health factors and alcohol consumption, to prevent the advancement of liver fibrosis or cirrhosis in this particular population.
Topics: Humans; Child; Prospective Studies; Diabetes Mellitus, Type 2; Liver; Liver Cirrhosis; Risk Factors; Hepatitis C, Chronic; Hepatitis C; Substance-Related Disorders
PubMed: 38532435
DOI: 10.1186/s13011-024-00603-z -
Journal of Alzheimer's Disease : JAD 2024Air pollution exposures ought to be of significant interest for the United States (US) public as health issues will play a role in the 2024 elections. Citizens are not...
Air pollution exposures ought to be of significant interest for the United States (US) public as health issues will play a role in the 2024 elections. Citizens are not aware of the harmful brain impact of exposures to ubiquitous anthropogenic combustion emissions and friction-derived nanoparticles, industrial nanoplastics, the growing risk of wildfires, and the smoke plumes of soot. Ample consideration of pediatric and early adulthood hallmarks of Alzheimer's disease, Parkinson's disease, frontotemporal lobar degeneration, and amyotrophic lateral sclerosis and associations with neuropsychiatric and neurodevelopmental disorders in the process of setting, reviewing, and implementing standards for particulate matter (PM)2.5, ultrafine PM, and industrial nanoparticles must be of interest to US citizens.
Topics: Humans; United States; Adult; Air Pollutants; Air Pollution; Particulate Matter; Alzheimer Disease; Neurodevelopmental Disorders
PubMed: 38517792
DOI: 10.3233/JAD-231373 -
European Journal of Public Health Jun 2024A large-scale industrial fire occurred in Rouen, France, in 2019. This study assessed the health-related quality of life of people exposed to its consequences 1 year...
BACKGROUND
A large-scale industrial fire occurred in Rouen, France, in 2019. This study assessed the health-related quality of life of people exposed to its consequences 1 year later.
METHODS
The study population comprised inhabitants of the exposed area and a non-exposed area. A representative sample was randomly selected using a stratified design. Data were collected using a standardized questionnaire to describe fire exposure and to calculate three health-related quality of life scores according to the SF12-v2 scale. After adjustment, descriptive and multivariate analyses were conducted.
RESULTS
The sample comprised 4773 participants (response rate 47.7%). In the exposed area, the average mental, physical and overall health scores were 47.5, 52.0 and 73.8 out of 100, respectively. Mean mental and overall health scores were higher in the non-exposed area (49.0 and 76.0, respectively). After adjustment, a lower mental health score was associated with a higher number of perceived types of exposure, reaching -3.72 points [-5.41; -2.04] for five or more different types of perceived exposure. A lower mental health score was associated with soot deposits (-1.04 [-1.70; -0.39]), perceiving odours [(-2.04 [-3.22; -0.86]) up to the day of data collection], and having seen, heard or been awakened by the fire (-1.21 [-1.90; -0.52]). A slightly lower physical health score was associated with soot deposits (-0.57 [-1.07; -0.08]).
CONCLUSION
This study highlighted associations between exposure to the consequences of the industrial fire in Rouen and a deterioration of perceived health-related quality of life 1 year later, particularly the mental health dimension.
Topics: Humans; Quality of Life; France; Male; Female; Middle Aged; Fires; Surveys and Questionnaires; Adult; Aged; Industry; Health Status; Environmental Exposure; Mental Health
PubMed: 38507556
DOI: 10.1093/eurpub/ckae047 -
Fa Yi Xue Za Zhi Feb 2024Biological evidence is relatively common evidence in criminal cases, and it has strong probative power because it carries DNA information for individual identification....
Biological evidence is relatively common evidence in criminal cases, and it has strong probative power because it carries DNA information for individual identification. At the scene of fire-related cases, the complex thermal environment, the escape of trapped people, the firefighting and rescue operations, and the deliberate destruction of criminal suspects will all affect the biological evidence in the fire scene. Scholars at home and abroad have explored and studied the effectiveness of biological evidence identification in fire scenes, and found that the blood stains, semen stains, bones, etc. are the main biological evidence which can be easily recovered with DNA in fire scenes. In order to analyze the research status and development trend of biological evidence in fire scenes, this paper systematically sorts out the relevant research, mainly including the soot removal technology, appearance method of typical biological evidence, and possibility of identifying other biological evidence. This paper also prospects the next step of research direction, in order to provide reference for the identification of biological evidence and improve the value of biological evidence in fire scenes.
Topics: Humans; Fires; Blood Stains; Body Fluids; Semen; DNA
PubMed: 38500463
DOI: 10.12116/j.issn.1004-5619.2022.520501 -
Environmental Science and Pollution... Apr 2024This study documents the socio-economic baselines in selected oil-impacted communities prior to the commencement of the Ogoni clean-up and restoration project. Adopting...
This study documents the socio-economic baselines in selected oil-impacted communities prior to the commencement of the Ogoni clean-up and restoration project. Adopting mixed approach consisting of semi-structured interviews, focus group discussions (FGDs), key informant interviews (KIIs), and household surveys, we surveyed the pre-remediation socio-economic conditions in the Ogoniland communities between July 2018 and March 2019. Results indicated that almost all respondents (99.6%) agreed that the smell of petroleum products or crude oil was evident in the air they breathed even as there were visible black particles (soot) in the respondents' nostrils, on their clothes, and in water. The respondents described the ambient air as smoky and choked with an offensive smell. The household waters were smelly, brownish, or oily, and most respondents (76%) cannot afford to treat their water. Forty-two percent of the respondents who relied on fishing and farming for a living sought for alternative means of subsistence and acknowledged that oil pollution caused stunted growth and low crop yield. The majority of respondents (91%) reported falling fish catches, while the fish caught smell and taste of oil, lowering their market value and posing a potential health risk to consumers. It is evident that oil pollution has impacted the socio-ecological values and sustainable livelihood in Ogoniland. This study provides baseline data for monitoring post-remediation socio-economic improvements in Ogoniland. It also highlights areas of urgent intervention to improve livelihood, and access to basic amenities (e.g., potable drinking water), waste management infrastructure, and statutory policy changes for sustainable development in Ogoniland.
Topics: Animals; Nigeria; Niger; Petroleum; Petroleum Pollution; Socioeconomic Factors; Water
PubMed: 38483715
DOI: 10.1007/s11356-024-32805-0 -
Sensors (Basel, Switzerland) Feb 2024This study proposes a novel multipoint transducer system by utilizing the single-mode-multimode-thin-cladding fiber (SMTC) structure. This structure leverages the...
This study proposes a novel multipoint transducer system by utilizing the single-mode-multimode-thin-cladding fiber (SMTC) structure. This structure leverages the disparity in mode field diameter between the multimode fiber (MMF) and thin-cladding fiber (TCF) to generate high-amplitude ultrasonic signals safely and efficiently. The fabricated transducer exhibits signal amplitudes 2-3-fold higher compared to conventional laser-ultrasonic transducers. Simulation analysis investigates the impact of the length of the MMF and the diameter of the TCF on coupling efficiency. The coupling efficiency of individual transducer units can be accurately controlled by adjusting the length of the MMF. A three-point energy-balanced laser-ultrasonic transducer system was achieved, with improved energy conversion efficiencies, and the optimal thickness of candle soot nanoparticles (CSNPs) is experimentally determined. Additionally, we carried out experiments to compare the performance of the proposed SMTC-based transducer system under different material conditions using two different photoacoustic materials: graphite-epoxy resin and candle soot nanoparticle-polydimethylsiloxane (CSNP-PDMS) composite. CSNPs, as a cost-effective and easy-to-prepare composite material, exhibit higher photoacoustic conversion efficiency compared to graphite-epoxy resin. The proposed system demonstrates the potential for applications in non-destructive testing techniques.
PubMed: 38475027
DOI: 10.3390/s24051491 -
Molecules (Basel, Switzerland) Feb 2024In this study, we employed a straightforward flame synthesis process to produce carbon soot containing carbon nano onions (CNOs) using easily accessible ghee oil as a...
In this study, we employed a straightforward flame synthesis process to produce carbon soot containing carbon nano onions (CNOs) using easily accessible ghee oil as a precursor. The ghee oil, with a molecular composition rich in more than 50 carbon atoms, served as an effective source for generating CNOs. The synthesized CNO particles underwent comprehensive characterization through high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) analyses, providing a detailed account of their physicochemical properties. In addition, we explored the direct deposition of CNOs on carbon fiber (CF) surfaces for 5 and 10 min via a soot deposition process. The resulting freeze-fracture images obtained from scanning electron microscope (SEM) offered insights into the morphology of the CNO-deposited CF. Our study aims to shed light on the potential applications of CNOs, focusing on their characterization and the possible benefits they may offer in diverse fields, including but not limited to enhancing interfacial bonding in thermoplastic composites.
PubMed: 38474440
DOI: 10.3390/molecules29050928