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1
Jasiński, Remigiusz. "Analysis of Particle Emissions from a Jet Engine including Conditions of Afterburner Use". Energies 15, n. 20 (18 ottobre 2022): 7696. http://dx.doi.org/10.3390/en15207696.
Testo completoAbstract (sommario):
Particle emissions from aircraft engines are mainly related to the emission of particles with very small diameters. The phenomena of the formation of particles in various operating conditions of turbine engines are known. However, it is difficult to find the results of research on the use of the afterburner in the literature. Increased aviation activity within military airports and situations such as air shows are associated with a very intense emission of particles, and pose a direct threat to human health. This article presents an analysis of particulate matter emissions from a military aircraft engine, with particular emphasis on operation with an afterburner. The parameters of the emission of particles determined were: PM Number Emissions Index (EIN), Particle Number Emissions Intensity (EN), PM Mass Emission Index (EIM), PM Mass Emission Intensity (EM), Differential Particle Number Emission Index, Differential Particle Volume Emission Index, and Differential Particle Mass Emission Index. The value of EIN for the afterburner use was the lowest among the whole operation range of the engine and was equal to 1.3 × 1015 particles per kilogram. The use of an afterburner resulted in a sharp increase in the EIM coefficient, which reached 670 mg/kg. Despite a very large increase in fuel consumption, the EIM coefficient turned out to be over 60 times greater than in the case of 100% engine thrust.
2
Karjalainen, Panu, Hilkka Timonen, Erkka Saukko, Heino Kuuluvainen, Sanna Saarikoski, Päivi Aakko-Saksa, Timo Murtonen et al. "Time-resolved characterization of primary particle emissions and secondary particle formation from a modern gasoline passenger car". Atmospheric Chemistry and Physics 16, n. 13 (14 luglio 2016): 8559–70. http://dx.doi.org/10.5194/acp-16-8559-2016.
Testo completoAbstract (sommario):
Abstract. Changes in vehicle emission reduction technologies significantly affect traffic-related emissions in urban areas. In many densely populated areas the amount of traffic is increasing, keeping the emission level high or even increasing. To understand the health effects of traffic-related emissions, both primary (direct) particulate emission and secondary particle formation (from gaseous precursors in the exhaust emissions) need to be characterized. In this study, we used a comprehensive set of measurements to characterize both primary and secondary particulate emissions of a Euro 5 level gasoline passenger car. Our aerosol particle study covers the whole process chain in emission formation, from the tailpipe to the atmosphere, and also takes into account differences in driving patterns. We observed that, in mass terms, the amount of secondary particles was 13 times higher than the amount of primary particles. The formation, composition, number and mass of secondary particles was significantly affected by driving patterns and engine conditions. The highest gaseous and particulate emissions were observed at the beginning of the test cycle when the performance of the engine and the catalyst was below optimal. The key parameter for secondary particle formation was the amount of gaseous hydrocarbons in primary emissions; however, also the primary particle population had an influence.
3
Feißel, Toni, Florian Büchner, Miles Kunze, Jonas Rost, Valentin Ivanov, Klaus Augsburg, David Hesse e Sebastian Gramstat. "Methodology for Virtual Prediction of Vehicle-Related Particle Emissions and Their Influence on Ambient PM10 in an Urban Environment". Atmosphere 13, n. 11 (18 novembre 2022): 1924. http://dx.doi.org/10.3390/atmos13111924.
Testo completoAbstract (sommario):
As a result of rising environmental awareness, vehicle-related emissions such as particulate matter are subject to increasing criticism. The air pollution in urban areas is especially linked to health risks. The connection between vehicle-related particle emissions and ambient air quality is highly complex. Therefore, a methodology is presented to evaluate the influence of different vehicle-related sources such as exhaust particles, brake wear and tire and road wear particles (TRWP) on ambient particulate matter (PM). In a first step, particle measurements were conducted based on field trials with an instrumented vehicle to determine the main influence parameters for each emission source. Afterwards, a simplified approach for a qualitative prediction of vehicle-related particle emissions is derived. In a next step, a virtual inner-city scenario is set up. This includes a vehicle simulation environment for predicting the local emission hot spots as well as a computational fluid dynamics model (CFD) to account for particle dispersion in the environment. This methodology allows for the investigation of emissions pathways from the point of generation up to the point of their emission potential.
4
Wang, Xinning, Yin Shen, Yanfen Lin, Jun Pan, Yan Zhang, Peter K. K. Louie, Mei Li e Qingyan Fu. "Atmospheric pollution from ships and its impact on local air quality at a port site in Shanghai". Atmospheric Chemistry and Physics 19, n. 9 (14 maggio 2019): 6315–30. http://dx.doi.org/10.5194/acp-19-6315-2019.
Testo completoAbstract (sommario):
Abstract. Growing shipping activities in port areas have generated negative impacts on climate, air quality and human health. To better evaluate the environmental impact of ship emissions, an experimental characterization of air pollution from ships was conducted in Shanghai Port in the summer of 2016. The ambient concentrations of gaseous NO, NO2, SO2 and O3 in addition to fine particulate matter concentrations (PM2.5), particle size distributions and the chemical composition of individual particles from ship emission were continuously monitored for 3 months. Ship emission plumes were visible at the port site in terms of clear peaks in the gaseous species and particulate matter concentrations. The SO2 and vanadium particle numbers were found to correlate best with ship emissions in Shanghai Port. Single-particle data showed that ship emission particles at the port site mainly concentrated in a smaller size range (<0.4 µm), where their number contributions were more important than their mass contributions to ambient particulate matter. The composition of ship emission particles at the port site suggested that they were mostly freshly emitted particles: their mass spectra were dominated by peaks of sulfate, elemental carbon (EC), and trace metals such as V, Ni, Fe and Ca, in addition to displaying very low nitrate signals. The gaseous NOx composition in some cases of plumes showed evidence of atmospheric transformation by ambient O3, which subsequently resulted in O3 depletion in the area. Quantitative estimations in this study showed that ship emissions contributed 36.4 % to SO2, 0.7 % to NO, 5.1 % to NO2, −0.9 % to O3, 5.9 % to PM2.5 and 49.5 % to vanadium particles in the port region if land-based emissions were included, and 57.2 % to SO2, 71.9 % to NO, 30.4 % to NO2, −16.6 % to O3, 27.6 % to PM2.5 and 77.0 % to vanadium particles if land-based emissions were excluded.
5
Karjalainen, P., H. Timonen, E. Saukko, H. Kuuluvainen, S. Saarikoski, P. Aakko-Saksa, T. Murtonen et al. "Time-resolved characterization of primary and secondary particle emissions of a modern gasoline passenger car". Atmospheric Chemistry and Physics Discussions 15, n. 22 (25 novembre 2015): 33253–82. http://dx.doi.org/10.5194/acpd-15-33253-2015.
Testo completoAbstract (sommario):
Abstract. Changes in traffic systems and vehicle emission reduction technologies significantly affect traffic-related emissions in urban areas. In many densely populated areas the amount of traffic is increasing, keeping the emission level high or even increasing. To understand the health effects of traffic related emissions, both primary and secondary particles that are formed in the atmosphere from gaseous exhaust emissions need to be characterized. In this study we used a comprehensive set of measurements to characterize both primary and secondary particulate emissions of a modern gasoline passenger car. Our aerosol particle study covers the whole process chain in emission formation, from the engine to the atmosphere, and takes into account also differences in driving patterns. We observed that in mass terms, the amount of secondary particles was 13 times higher than the amount of primary particles. The formation, composition, number, and mass of secondary particles was significantly affected by driving patterns and engine conditions. The highest gaseous and particulate emissions were observed at the beginning of the test cycle when the performance of the engine and the catalyst was below optimal. The key parameter for secondary particle formation was the amount of gaseous hydrocarbons in primary emissions; however, also the primary particle population had an influence. Thus, in order to enhance human health and wellbeing in urban areas, our study strongly indicates that in future legislation, special attention should be directed into the reduction of gaseous hydrocarbons.
6
Gomes Nogueira, Ana Paula, Davide Carlevaris, Cinzia Menapace e Giovanni Straffelini. "Tribological and Emission Behavior of Novel Friction Materials". Atmosphere 11, n. 10 (30 settembre 2020): 1050. http://dx.doi.org/10.3390/atmos11101050.
Testo completoAbstract (sommario):
The tribological behavior and the related airborne particles emission of three copper-free automotive friction materials are investigated. The tests were conducted using a pin-on-disc tribometer equipped with a specifically designed clean-enclosure chamber for the emission measurement. Particle number concentration from particle size 0.3 µm up to 10 µm and the mass of emitted particles between 1 µm to 10 µm were measured. Particular emphasis was given to the chemical composition of the bulk materials, the friction layers and the emissions, in order to explain the acting wear mechanisms, and the recorded emission of airborne particles. The results indicate that the recorded emissions do not correlate with the friction coefficient and the wear rates, since the wear mechanisms exert a different influence on the tribological and emission behavior of the materials under study.
7
Lou, Diming, Guokang Lou, Bo Wang, Liang Fang e Yunhua Zhang. "Effect of LP-EGR on the Emission Characteristics of GDI Engine". Machines 10, n. 1 (22 dicembre 2021): 7. http://dx.doi.org/10.3390/machines10010007.
Testo completoAbstract (sommario):
Exhaust gas recirculation (EGR) can improve the fuel economy of gasoline direct-injection (GDI) engines, but at the same time it will have a significant impact on emissions. In this paper, the effects of low-pressure exhaust gas recirculation (LP-EGR) and its rate on the main gaseous and particulate emission characteristic of a GDI engine were investigated. The results showed that the particle size distribution of the GDI engine presented bimodal peaks in nucleation and accumulation mode, and the nucleation mode particles comprised the vast majority of the total particles. The effect of LP-EGR on emissions depended on the engine conditions. At low and medium speed, the particle emissions increased with the increase in the EGR rate, while at high speed, a reduction in the particle emission was observed. When the engine operated in full load condition, an increase in the EGR rate reduced the particle number (PN) concentration significantly, but increased the particle mass (PM) concentration. In terms of the gaseous emission, the EGR could reduce as much as 80% of the NOx emission; however, the total hydrocarbons (THC) emission presented an increased trend, and the maximum increase reached 23.5%. At low and medium loads, the EGR could reduce the CO emission, but at high load, the CO emission worsened with the EGR.
8
Josephson, Alexander J., Daniel Castaño, Marlin J. Holmes e Rodman R. Linn. "Simulation Comparisons of Particulate Emissions from Fires under Marginal and Critical Conditions". Atmosphere 10, n. 11 (13 novembre 2019): 704. http://dx.doi.org/10.3390/atmos10110704.
Testo completoAbstract (sommario):
Using a particulate emissions model developed for FIRETEC, we explore differences in particle emission profiles between high-intensity fires under critical conditions and low-intensity fires under marginal conditions. Simulations were performed in a chaparral shrubland and a coniferous pine forest representative of the southeast United States. In each case, simulations were carried out under marginal and critical fire conditions. Marginal fire conditions include high moisture levels and low winds, often desired for prescribed fires as these conditions produce a low-intensity burn with slower spread rates. Critical fire conditions include low moisture levels and high winds, which easily lead to uncontrollable wildfires which produce a high-intensity burn with faster spread rates. These simulations’ resultant particle emission profiles show critical fire conditions generate larger particle emission factors, higher total mass emissions, and a higher lofting potential of particles into the atmosphere when compared against marginal fire conditions but similar particle size distrubtions. In addition, a sensitivity analysis of the emissions model was performed to evaluate key parameters which govern particle emission factor and particle size.
9
Bai, Fengyue, Chong Wang, Hongyuan Wei, Lin Zhang e Xiaowei Wang. "Study on particulate matter emission characteristics and its influencing factors of a drum brake". Journal of Physics: Conference Series 2963, n. 1 (1 febbraio 2025): 012024. https://doi.org/10.1088/1742-6596/2963/1/012024.
Testo completoAbstract (sommario):
Abstract The particle emission characteristics of a drum brake under different braking cycles and braking conditions are studied based on the inertia test bench, brake sealing chamber, and particle test equipment. The results show that a large number of particles are generated during the braking process, and the number of solid particles at a nominal particle size of approximately 10 nm electrical mobility diameter and larger (SPN10) emission factor can reach 8.927×109 #/km under different braking cycles. With the increase of initial braking speed, initial braking temperature, and vehicle load, the brake wear particulate generated in the braking process increases. The total brake wear particulate number emission has a quadratic function relationship with the initial braking speed and a linear relationship with the initial braking temperature. Brake deceleration has little effect on total brake wear particulate number emissions produced in one brake process.
10
Hamatschek, Christopher, Klaus Augsburg, David Schobel, Sebastian Gramstat, Anton Stich, Florian Gulden e David Hesse. "Comparative Study on the Friction Behaviour and the Particle Formation Process between a Laser Cladded Brake Disc and a Conventional Grey Cast Iron Disc". Metals 13, n. 2 (1 febbraio 2023): 300. http://dx.doi.org/10.3390/met13020300.
Testo completoAbstract (sommario):
Brake-wear particle emissions are the result of the components of a friction brake being in tribological contact, and they are classified as non-exhaust emissions. Since most of the emitted particles belong to the size classes of particulate matter (≤10 μm) and differ significantly in terms of their physico-chemical properties from automotive exhaust emissions, this source is of particular relevance to human health and, therefore, the focus of scientific studies. Previous studies have shown that coated brake discs offer significant wear and emission reduction potential. Nevertheless, no studies are available that describe the specific particle formation process, the contact conditions, the structure of the friction layer and the differences compared to conventional grey cast iron discs. The aim of this study is to describe those differences. For this purpose, the tribological behaviour, the structure of the friction layer and the associated particle dynamics within the friction contact between a laser cladding coated disc and a conventional grey cast iron disc are compared. The required investigations are carried out both ex situ (stationary) and in situ (dynamic). Parallel to the tribological investigations, the particle emission behaviour is determined on an inertia dynamometer using a constant volume sampling system (CVS) and equipment for particle number and particle size distribution measurement. The results show that, for two different brake pads, the laser cladding brake disc has lower wear and less particulate emissions than the grey cast iron brake disc. The wear behaviour of the coating varies significantly for the two brake pads. By contrast, the grey cast iron brake disc shows a significantly lower influence.
11
Giechaskiel, Barouch, Anastasios Melas, Giorgio Martini, Panagiota Dilara e Leonidas Ntziachristos. "Revisiting Total Particle Number Measurements for Vehicle Exhaust Regulations". Atmosphere 13, n. 2 (18 gennaio 2022): 155. http://dx.doi.org/10.3390/atmos13020155.
Testo completoAbstract (sommario):
Road transport significantly contributes to air pollution in cities. Emission regulations have led to significantly reduced emissions in modern vehicles. Particle emissions are controlled by a particulate matter (PM) mass and a solid particle number (SPN) limit. There are concerns that the SPN limit does not effectively control all relevant particulate species and there are instances of semi-volatile particle emissions that are order of magnitudes higher than the SPN emission levels. This overview discusses whether a new metric (total particles, i.e., solids and volatiles) should be introduced for the effective regulation of vehicle emissions. Initially, it summarizes recent findings on the contribution of road transport to particle number concentration levels in cities. Then, both solid and total particle emission levels from modern vehicles are presented and the adverse health effects of solid and volatile particles are briefly discussed. Finally, the open issues regarding an appropriate methodology (sampling and instrumentation) in order to achieve representative and reproducible results are summarized. The main finding of this overview is that, even though total particle sampling and quantification is feasible, details for its realization in a regulatory context are lacking. It is important to define the methodology details (sampling and dilution, measurement instrumentation, relevant sizes, etc.) and conduct inter-laboratory exercises to determine the reproducibility of a proposed method. It is also necessary to monitor the vehicle emissions according to the new method to understand current and possible future levels. With better understanding of the instances of formation of nucleation mode particles it will be possible to identify its culprits (e.g., fuel, lubricant, combustion, or aftertreatment operation). Then the appropriate solutions can be enforced and the right decisions can be taken on the need for new regulatory initiatives, for example the addition of total particles in the tailpipe, decrease of specific organic precursors, better control of inorganic precursors (e.g., NH3, SOx), or revision of fuel and lubricant specifications.
12
Grigoriadis, Achilleas, Nikolaos Kousias, Anastasios Raptopoulos-Chatzistefanou, Håkan Salberg, Jana Moldanová, Anna-Lunde Hermansson, Yingying Cha et al. "Particulate and Gaseous Emissions from a Large Two-Stroke Slow-Speed Marine Engine Equipped with Open-Loop Scrubber under Real Sailing Conditions". Atmosphere 15, n. 7 (17 luglio 2024): 845. http://dx.doi.org/10.3390/atmos15070845.
Testo completoAbstract (sommario):
Particulate and gaseous emissions were studied from a large two-stroke slow-speed diesel engine equipped with an open-loop scrubber, installed on a 78,200 metric tonnes (deadweight) containership, under real operation. This paper presents the on-board emission measurements conducted upstream and downstream of the scrubber with heavy fuel oil (HFO) and ultra-low sulfur fuel oil (ULSFO). Particle emissions were examined under various dilution ratios and temperature conditions, and with two thermal treatment setups, involving a thermodenuder (TD) and a catalytic stripper (CS). Our results show a 75% SO2 reduction downstream of the scrubber with the HFO to emission-compliant levels, while the use of the ULSFO further decreased SO2 levels. The operation of the scrubber produced higher particle number levels compared to engine-out, attributed to the condensational growth of nanometer particle cores, salt and the formation of sulfuric acid particles in the smaller size range, induced by the scrubber. The use of a TD and a CS eliminates volatiles but can generate new particles when used in high-sulfur conditions. The results of this study contribute to the generally limited understanding of the particulate and gaseous emission performance of open-loop scrubbers in ships and could feed into emission and air quality models for estimating marine pollution impacts.
13
Zhao, Yujiao, Mengyao Wang, Pengfei Tao, Guozhi Qiu e Xueying Lu. "Emission Characteristics of Particulate Matter from Boiling Food". Atmosphere 14, n. 1 (12 gennaio 2023): 167. http://dx.doi.org/10.3390/atmos14010167.
Testo completoAbstract (sommario):
Cooking food in water or soup, such as hot pot, is a widely used cooking method in China. This type of cooking requires no oil and cooks at a lower temperature, but that does not mean it produces fewer pollutants or is less harmful. There are few research studies on the emission characteristics and mechanisms of particulate matter emissions when eating hot pot (the boiling process), which leads to the unreasonable design of ventilation systems for this kind of catering. In this paper, the effects of boiling different ingredients (including noodles, potatoes, fish, tofu, meatballs, and pork) on particle number concentration emissions were studied. The particle number concentration and particle size distribution of PM with diameters of 0.3 μm and less, 0.3–0.5 μm and 0.5–1.0 μm (PM0.3, PM0.3–0.5 and PM0.5–1.0, respectively) were measured in an experimental chamber. The food type and shape showed very little change in the PM emission characteristics of boiling. When the boiling state was reached, the number concentration, particle size distribution, and arithmetic mean diameter of particles all fluctuated within 60 s. The emission characteristics of particles produced by boiling water and heating oil were compared. Heating oil produced more small particles, and boiling water released more large particles. Transient and steady methods were used to calculate the emission rate of particles, and the steady-state calculation has a high estimation of the emission rate.
14
Petters, Markus D., Tyas Pujiastuti, Ajmal Rasheeda Satheesh, Sabin Kasparoglu, Bethany Sutherland e Nicholas Meskhidze. "Wind-driven emissions of coarse-mode particles in an urban environment". Atmospheric Chemistry and Physics 24, n. 1 (18 gennaio 2024): 745–62. http://dx.doi.org/10.5194/acp-24-745-2024.
Testo completoAbstract (sommario):
Abstract. Quantifying surface–atmosphere exchange rates of particles is important for understanding the role of suspended particulate matter in radiative transfer, clouds, precipitation, and climate change. Emissions of coarse-mode particles with a diameter greater than 0.5 µm provide giant cloud condensation nuclei and ice nuclei. These emissions are critical for understanding the evolution of cloud microphysical properties yet remain poorly understood. Here we introduce a new method that uses lidar retrievals of the elastic backscatter and Doppler velocity to obtain surface number emissions of particles with a diameter greater than 0.53 µm. The technique is applied to study particle number fluxes over a 2-month period from 1 June to 10 August 2022 during the TRACER campaign at an urban site near Houston, TX, USA. We found that all the observed fluxes were positive (upwards), indicating particle emission from the surface. The fluxes followed a diurnal pattern and peaked near noon local time. Flux intensity varied through the 2 months with multi-day periods of strong fluxes and multi-day periods of weak fluxes. Emission particle number fluxes peaked near ∼ 100 cm−2 s−1. The daily averaged emission fluxes correlated with friction velocity and were anticorrelated with surface relative humidity. The emission flux can be parameterized as F= 3000 u*4, where u* is the friction velocity in m s−1 and the emission flux F is in cm−2 s−1. The u* dependence is consistent with emission from wind-driven erosion. Estimated values for the mass flux are in the lower range of literature values from non-urban sites. These results demonstrate that urban environments may play an important role in supplying coarse-mode particles to the boundary layer. We anticipate that quantification of these emissions will help constrain aerosol–cloud interaction models that use prognostic aerosol schemes.
15
Zhong, Chongzhi, Jiaxing Sun, Jing Zhang, Zishu Liu, Tiange Fang, Xiaoyu Liang, Jiawei Yin et al. "Characteristics of Vehicle Tire and Road Wear Particles’ Size Distribution and Influencing Factors Examined via Laboratory Test". Atmosphere 15, n. 4 (29 marzo 2024): 423. http://dx.doi.org/10.3390/atmos15040423.
Testo completoAbstract (sommario):
With the implementation of strict emission regulations and the use of cleaner fuels, there has been a considerable reduction in exhaust emissions. However, the relative contribution of tire wear particles (TWPs) to particulate matters is expected to gradually increase. This study conducted laboratory wear experiments on tires equipped on domestically popular vehicle models, testing the factors and particle size distribution of TWPs. The results showed that the content of tire wear particle emission was mainly ultrafine particles, accounting for 94.80% of particles ranging from 6 nm to 10 μm. There were at least two concentration peaks for each test condition and sample, at 10~13 nm and 23~41 nm, respectively. The mass of TWP emission was mainly composed of fine particles and coarse particles, with concentration peaks at 0.5 μm and 1.3–2.5 μm, respectively. Both the number and mass of TWPs exhibited a bimodal distribution, with significant differences in emission intensity among different tire samples. However, there was a good exponential relationship between PM10 mass emissions from tire wear and tire camber angle. The orthogonal experimental results showed that the slip angle showed the greatest impact on TWP emission, followed by speed and load, with the smallest impact from inclination angle.
16
Boykin, Clif, Michael Buser, Derek Whitelock e Gregory Holt. "Overflow System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 554–66. http://dx.doi.org/10.56454/ptqd2556.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 emission factor quality ratings for cotton gin PM10 (particulate matter with nominal diameter less than or equal to 10 µm) data are questionable, being extremely low. The objective of this study was to characterize particulate emissions for overflow systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from three gins (9 total test runs) were 0.00048 kg/227-kg bale (0.0011 lb/500-lb bale), 0.0049 kg/bale (0.011 lb/bale), and 0.0089 kg/bale (0.020 lb/bale), respectively. The overflow system particle size distributions were characterized by an average mass median diameter of 18.7 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 1.67%, PM6 to total particulate was 17.0%, and PM10 to total particulate was 31.0%.
17
Paasonen, Pauli, Kaarle Kupiainen, Zbigniew Klimont, Antoon Visschedijk, Hugo A. C. Denier van der Gon e Markus Amann. "Continental anthropogenic primary particle number emissions". Atmospheric Chemistry and Physics 16, n. 11 (6 giugno 2016): 6823–40. http://dx.doi.org/10.5194/acp-16-6823-2016.
Testo completoAbstract (sommario):
Abstract. Atmospheric aerosol particle number concentrations impact our climate and health in ways different from those of aerosol mass concentrations. However, the global, current and future anthropogenic particle number emissions and their size distributions are so far poorly known. In this article, we present the implementation of particle number emission factors and the related size distributions in the GAINS (Greenhouse Gas–Air Pollution Interactions and Synergies) model. This implementation allows for global estimates of particle number emissions under different future scenarios, consistent with emissions of other pollutants and greenhouse gases. In addition to determining the general particulate number emissions, we also describe a method to estimate the number size distributions of the emitted black carbon particles. The first results show that the sources dominating the particle number emissions are different to those dominating the mass emissions. The major global number source is road traffic, followed by residential combustion of biofuels and coal (especially in China, India and Africa), coke production (Russia and China), and industrial combustion and processes. The size distributions of emitted particles differ across the world, depending on the main sources: in regions dominated by traffic and industry, the number size distribution of emissions peaks in diameters range from 20 to 50 nm, whereas in regions with intensive biofuel combustion and/or agricultural waste burning, the emissions of particles with diameters around 100 nm are dominant. In the baseline (current legislation) scenario, the particle number emissions in Europe, Northern and Southern Americas, Australia, and China decrease until 2030, whereas especially for India, a strong increase is estimated. The results of this study provide input for modelling of the future changes in aerosol–cloud interactions as well as particle number related adverse health effects, e.g. in response to tightening emission regulations. However, there are significant uncertainties in these current emission estimates and the key actions for decreasing the uncertainties are pointed out.
18
Buser, Michael, Derek Whitelock, Clif Boykin e Gregory Holt. "Unloading System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 591–602. http://dx.doi.org/10.56454/ytlk1061.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 emission factor quality ratings for cotton gin PM10 (particulate matter with nominal diameter less than or equal to 10 µm) data are questionable, being extremely limited. The objective of this study was to characterize particulate emissions for unloading systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from three gins (nine total test runs) were 0.0059 kg/227-kg bale (0.013 lb/500-lb bale), 0.053 kg/bale (0.117 lb/bale), and 0.084 kg/bale (0.185 lb/bale), respectively. The unloading system particle size distributions were characterized by an average mass median diameter of 7.5 µm aerodynamic equivalent diameter (AED). Based on system average emission factors, the ratio of PM2.5 to total particulate was 4.39%, PM6 to total particulate was 39.5%, and PM10 to total particulate was 62.3%.
19
Moreira, Fernando Miguel, Ana Ferreira e Nelson Barros. "Determination of Occupational Exposure to Ultrafine Particles in Different Sectors of Activity". Safety 10, n. 1 (15 marzo 2024): 30. http://dx.doi.org/10.3390/safety10010030.
Testo completoAbstract (sommario):
The primary sources of ultrafine particulate matter are linked to human activity. Certain particulate emissions, particularly those of a finer nature, can significantly impact human health, making them one of the most concerning pollutants. Ultrafine particles (UFPs), which have a diameter of less than 100 nm, are of particular concern due to their impact on human health and the difficulty in controlling them. The concentration of ultrafine particles (UFPs) in the workplace is a growing concern and is classified as an emerging risk. Workers may be exposed to UFPs through inhalation, skin absorption, ingestion, or a combination of these routes. This study aims to determine the levels of UFP exposure among workers in environments with varying direct particle emission patterns. Measurements were conducted to compare the results with the levels recommended by the WHO. The study monitored industrial workplaces with direct particulate matter emissions, such as a carpentry workshop and a bakery, as well as social sector sites without or almost without direct particle emissions, such as a school and a health clinic. One conclusion drawn from this study is that all tasks and occupations are susceptible to high levels of UFPs, exceeding WHO recommended values in virtually all monitored environments. Therefore, monitoring and controlling UFPs is crucial. Further in-depth studies on this subject are also necessary.
20
Whitelock, Derek, Michael Buser, Clif Boykin e Gregory Holt. "Second Stage Mote System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 504–16. http://dx.doi.org/10.56454/kzio1772.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, EPA AP-42 included combined 1st and 2nd stage mote system PM10 (particulate matter with nominal diameter less than or equal to 10 µm) and total particulate emission factors and not individual mote system emission factors. The objective of this study was to characterize particulate emissions for 2nd stage mote systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from five gins (15 total test runs) were 0.00030 kg/227-kg bale (0.00067 lb/500-lb bale), 0.0024 kg/bale (0.0054 lb/bale), and 0.0039 kg/bale (0.0087 lb/bale), respectively. The 2nd stage mote system particle size distributions were characterized by an average mass median diameter of 16.1 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 2.87%, PM6 to total particulate was 23.0%, and PM10 to total particulate was 23.0%.
21
Buser, Michael, Derek Whitelock, Clif Boykin e Gregory Holt. "First Stage Mote System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 491–503. http://dx.doi.org/10.56454/xglt5780.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 included combined mote cleaner PM10 (particulate matter with nominal diameter less than or equal to 10 µm) and total particulate emission factors and not individual mote system emission factors. The objective of this study was to characterize particulate emissions for 1st stage mote systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from five gins (14 total test runs) were 0.00063 kg/227-kg bale (0.0014 lb/500-lb bale), 0.0054 kg/bale (0.012 lb/bale), and 0.0091 kg/bale (0.020 lb/bale), respectively. The 1st stage mote system particle size distributions were characterized by an average mass median diameter of 16.4 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 2.49%, PM6 to total was 21.6%, and PM10 to total was 36.0%.
22
Boykin, Clif, Michael Buser, Derek Whitelock e Gregory Holt. "Combined Mote System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 517–27. http://dx.doi.org/10.56454/nypk9659.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 emission factor quality ratings for cotton gin PM10 (particulate matter with nominal diameter less than or equal to 10 µm) data are questionable, being extremely low. The objective of this study was to characterize particulate emissions for combined mote systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from two gins (six total test runs) were 0.0026 kg/227-kg bale (0.0056 lb/500-lb bale), 0.030 kg/bale (0.065 lb/bale), and 0.052 kg/bale (0.115 lb/bale), respectively. The combined mote system particle size distributions were characterized by an average mass median diameter of 15.8 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 1.75%, PM6 to total particulate was 20.4%, and PM10 to total particulate was 35.7%.
23
Whitelock, Derek, Michael Buser, Clif Boykin e Gregory Holt. "Master Trash System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 541–53. http://dx.doi.org/10.56454/pguc4338.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 emission factor quality ratings for cotton gin PM10 (particulate matter with nominal diameter less than or equal to 10 µm) data are questionable, being extremely low. The objective of this study was to characterize particulate emissions for master trash systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from five gins (15 total test runs) were 0.0035 kg/227-kg bale (0.0076 lb/500-lb bale), 0.026 kg/bale (0.058 lb/bale), and 0.048 kg/bale (0.106 lb/bale), respectively. The master trash system particle size distributions were characterized by an average mass median diameter of 20.6 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 1.86%, PM6 to total particulate was 14.0%, and PM10 to total particulate was 25.7%.
24
Buser, Michael, Derek Whitelock, Clif Boykin e Gregory Holt. "Mote Trash System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 567–78. http://dx.doi.org/10.56454/vqhi9732.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 emission factor quality ratings for cotton gin PM10 (particulate matter with nominal diameter less than or equal to 10 µm) data are questionable, being extremely low. The objective of this study was to characterize particulate emissions for mote trash systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured of PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from two gins (6 total test runs) were 0.00031 kg/227-kg bale (0.00068 lb/500-lb bale), 0.0023 kg/bale (0.0051 lb/bale), and 0.0042 kg/bale (0.0093 lb/bale), respectively. The mote trash system particle size distributions were characterized by an average mass median diameter of 23.9 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 1.75%, PM6 to total particulate was 13.3%, and PM10 to total particulate was 24.2%.
25
Boykin, Clif, Michael Buser, Derek Whitelock e Gregory Holt. "Cyclone Robber System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 478–90. http://dx.doi.org/10.56454/eklt6904.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 emission factor quality ratings for cotton gin PM10 (particulate matter with nominal diameter less than or equal to 10 µm) data are questionable, being extremely low. The objective of this study was to characterize particulate emissions for cyclone robber systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from three gins (12 total test runs) were 0.00042 kg/227-kg bale (0.00093 lb/500-lb bale), 0.0035 kg/bale (0.0078 lb/bale), and 0.0061 kg/bale (0.013 lb/bale), respectively. The cyclone robber system particle size distributions were characterized by an average mass median diameter of 20.3 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 2.10%, PM6 to total particulate was 17.5%, and PM10 to total particulate was 30.3%.
26
Whitelock, Derek, Michael Buser, Clif Boykin e Gregory Holt. "Battery Condenser System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 465–77. http://dx.doi.org/10.56454/dali5351.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 emission factor quality ratings for cotton gin PM10 (particulate matter with nominal diameter less than or equal to 10 µm) data are questionable, being extremely low. The objective of this study was to characterize particulate emissions for battery condenser systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from six gins (17 total test runs) were 0.00036 kg/227-kg bale (0.00078 lb/500-lb bale), 0.0042 kg/bale (0.0093 lb/bale), and 0.0078 kg/bale (0.017 lb/bale), respectively. The battery condenser system particle size distributions were characterized by an average mass median diameter of 24.5 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 1.11%, PM6 to total particulate was 13.2%, and PM10 to total particulate was 24.3%.
27
Deme, Dániel, e András Telekes. "Onkológiai betegek szoros képalkotó követése – előny vagy hátrány?" Orvosi Hetilap 157, n. 39 (settembre 2016): 1538–45. http://dx.doi.org/10.1556/650.2016.30542.
Testo completoAbstract (sommario):
The International Commission on Radiological Protection estimates, that 100 mSv exposure of radiation increases cancer risk by 0.5%. The central hypothesis of the Linear No Threshold model is that low dose ionizing radiation can induce carcinogenesis through the so called “one hit action”, that is one or more deoxyribonucleic acid strands can be broken by the hit of only one electron particule. Regardless of the radiation dose, radiation exposure increases cancer risk. In the United States of America, one-third of computed tomographic scans are carried with no clear clinical indication, i.e. non radiating imaging can be applied with equal sensitivity and specificity. Furthermore, computed tomographic scans are repeated unnecessarily. Although technical improvements have reduced the concern of the potential danger of radiation exposure, the cumulative aspects and cancer risk should always be considered. Cancer risk, accompanied by ionizing radiation, should be minimized during the follow up of oncologic patients. It is mandatory, that all diagnostic tools which are not using ionizing radiation should be made widely accessable (eg. whole body diffusion weighted magnetic resonance imaging, positron emission tomography/magnetic resonance imaging). Orv. Hetil., 2016, 157(39), 1538–1545.
28
Pacura, Wiktor, Katarzyna Szramowiat-Sala, Mariusz Macherzyński, Janusz Gołaś e Piotr Bielaczyc. "Analysis of Micro-Contaminants in Solid Particles from Direct Injection Gasoline Vehicles". Energies 15, n. 15 (7 agosto 2022): 5732. http://dx.doi.org/10.3390/en15155732.
Testo completoAbstract (sommario):
Exhaust emissions from vehicles are the subject of numerous studies and legal acts. In the European Union, exhaust emissions are regulated by “Euro” emission standards, which limit emissions of gaseous pollutants such as CO, CO2, HC, and NOx, as well as the particulate matter (PM) and particle number (PN). Solid particles consist of a number of micro-contaminants, inter alia polycyclic aromatic hydrocarbons (PAHs) and their nitrated and oxygenated derivatives. Despite their highly mutagenic and carcinogenic character, these micro-contaminants are not regulated in Euro emissions standards. This paper presents both a general discussion of the phenomenon of particulate formation in and emission from direct injection gasoline engines, as well as a wide range of results on the subject. The subject of the micro-contaminants in solid particles from modern gasoline vehicles is explored. The samples of solid particles were collected from 11 groups of vehicles according to the WLTP test methodology. Solid particles from gasoline vehicles were analyzed via various analytical techniques, including ion chromatography (IC) to measure selected anion concentrations, gas chromatography with mass spectroscopy (GC-MS) to study 16 PAHs and selected PAH derivatives, scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS) for images and elemental composition, and microwave plasma atomic emission spectroscopy (MP-AES) for qualitative screening analysis of 19 elements. The study of non-regulated compounds is crucial in efforts to establish the influence of solid particles on health and the environment. Furthermore, extended studies can provide a basis for further research on vehicle emissions or other fields, such as medicine or material engineering.
29
Wang, Xiaowei, Lin Zhang, Mingda Wang, Xiaojun Jing e Xuejing Gu. "Sub-23 nm Solid Particle Number Emission Characteristics for a Heavy-duty Engine Fuelled with Compression Natural Gas". E3S Web of Conferences 329 (2021): 01012. http://dx.doi.org/10.1051/e3sconf/202132901012.
Testo completoAbstract (sommario):
Cold and hot WHTC (World harmonized Transient-State Cycle) were separately run on the engine test bed for a heavy-duty natural gas engine fuelled with high calorific value natural gas and low calorific value natural gas. The particle emissions including PN10 (number of particles above 10nm) and PN23 (number of particles above 23nm) were measured. The results show that the transient emission of PN10 and PN23 have basically the same trends. The weighted specific emission of PN10 is 21.6 times of PN23. Cold start PN emissions account for a relatively large proportion. Fuel property has a great influence on the PN emissions of natural gas engines. The increase of carbon-containing fuels such as methane and ethane in the fuel gas will lead to a rapid increase in PN emissions especially in the cold start process. It is extremely important to strengthen the control of sub-23nm particulate emissions for heavy-duty natural gas engines.
30
BIELACZYC, Piotr, Andrzej SZCZOTKA e Joseph WOODBURN. "An overview of particulate matter emissions from modern light duty vehicles". Combustion Engines 153, n. 2 (1 maggio 2013): 101–8. http://dx.doi.org/10.19206/ce-117007.
Testo completoAbstract (sommario):
This paper presents a comparison of particle mass and number emissions from different types of vehicles with spark-ignition (SI) engines, with MPI and DI fuelling systems and compression-ignition (CI) engines with DI fuelling system with/without Diesel particles filters (DPF). The methodology of particulate mass and particle number emissions measurement with a full flow dilution tunnel for LDD engines and particulate sampling system is described. The results of measurements performed according to Euro 5/Euro 6 requirements for PC and LDV vehicles are presented, as performed on the chassis dynamometer in the Exhaust Emission Laboratory of BOSMAL Automotive Research and Development Institute (in Bielsko-Biala), Poland.
31
Whitelock, Derek, Michael Buser, Clif Boykin e Gregory Holt. "First Stage Lint Cleaning System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 427–39. http://dx.doi.org/10.56454/lmkj5641.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 included combined lint cleaner PM10 (particulate matter with nominal diameter less than or equal to 10 µm) and total particulate emission factors and not individual lint cleaner emission factors. The objective of this study was to characterize particulate emissions for the 1st stage lint cleaning systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from four gins (10 total test runs) were 0.0010 kg/227-kg bale (0.0022 lb/500-lb bale), 0.0078 kg/bale (0.017 lb/bale), and 0.014 kg/bale (0.031 lb/bale), respectively. The 1st stage lint cleaning system particle size distributions were characterized by an average mass median diameter of 29.2 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 1.39%, PM6 to total particulate was 11.1%, and PM10 to total particulate was 20.2%.
32
Boykin, Clif, Michael Buser, Derek Whitelock e Gregory Holt. "Second Stage Lint Cleaning System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 440–52. http://dx.doi.org/10.56454/vhhz1475.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 included combined lint cleaner PM10 (particulate matter with nominal diameter less than or equal to 10 µm) and total particulate emission factors and not individual lint cleaner emission factors. The objective of this study was to characterize particulate emissions for 2nd stage lint cleaning systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from four gins (6 total test runs) were 0.00024 kg/227-kg bale (0.00052 lb/500-lb bale), 0.0026 kg/bale (0.0057 lb/bale), and 0.0048 kg/bale (0.010 lb/bale), respectively. The 2nd stage lint cleaning system particle size distributions were characterized by an average mass median diameter of 29.8 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 1.04%, PM6 to total particulate was 11.4%, and PM10 to total particulate was 20.9%.
33
Heintzenberg, Jost, Wolfram Birmili, Bryan Hellack, Gerald Spindler, Thomas Tuch e Alfred Wiedensohler. "Aerosol pollution maps and trends over Germany with hourly data at four rural background stations from 2009 to 2018". Atmospheric Chemistry and Physics 20, n. 18 (24 settembre 2020): 10967–84. http://dx.doi.org/10.5194/acp-20-10967-2020.
Testo completoAbstract (sommario):
Abstract. A total of 10 years of hourly aerosol and gas data at four rural German stations have been combined with hourly back trajectories to the stations and inventories of the European Emissions Database for Global Atmospheric Research (EDGAR), yielding pollution maps over Germany of PM10, particle number concentrations, and equivalent black carbon (eBC). The maps reflect aerosol emissions modified with atmospheric processes during transport between sources and receptor sites. Compared to emission maps, strong western European emission centers do not dominate the downwind concentrations because their emissions are reduced by atmospheric processes on the way to the receptor area. PM10, eBC, and to some extent also particle number concentrations are rather controlled by emissions from southeastern Europe from which pollution transport often occurs under drier conditions. Newly formed particles are found in air masses from a broad sector reaching from southern Germany to western Europe, which we explain with gaseous particle precursors coming with little wet scavenging from this region. Annual emissions for 2009 of PM10, BC, SO2, and NOx were accumulated along each trajectory and compared with the corresponding measured time series. The agreement of each pair of time series was optimized by varying monthly factors and annual factors on the 2009 emissions. This approach yielded broader summer emission minima than published values that were partly displaced from the midsummer positions. The validity of connecting the ambient concentration and emission of particulate pollution was tested by calculating temporal changes in eBC for subsets of back trajectories passing over two separate prominent emission regions, region A to the northwest and B to the southeast of the measuring stations. Consistent with reported emission data the calculated emission decreases over region A are significantly stronger than over region B.
34
Buser, Michael, Derek Whitelock, Clif Boykin e Gregory Holt. "Mote Cyclone Robber System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 529–40. http://dx.doi.org/10.56454/qxka7531.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 did not include PM10 (particulate matter with nominal diameter less than or equal to 10 µm) and total particulate emission factors for mote cyclone robber systems. The objective of this study was to characterize particulate emissions for mote cyclone robber systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from three gins (9 total test runs) were 0.0011 kg/227-kg bale (0.0024 lb/500-lb bale), 0.0085 kg/bale (0.019 lb/bale), and 0.015 kg/bale (0.032 lb/bale), respectively. The mote cyclone robber system particle size distributions were characterized by an average mass median diameter of 21.2 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 2.20%, PM6 to total particulate was 16.9%, and PM10 to total particulate was 29.0%.
35
Buser, Michael, Derek Whitelock, Clif Boykin e Gregory Holt. "Combined Lint Cleaning System Particulate Emission Factors for Cotton Gins: Particle Size Distribution Characteristics". Journal of Cotton Science 19, n. 3 (novembre 2015): 453–64. http://dx.doi.org/10.56454/pymi8650.
Testo completoAbstract (sommario):
This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006 and again in 2013, the United States (U.S.) Environmental Protection Agency (EPA) published a more stringent National Ambient Air Quality Standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created an urgent need to collect additional cotton gin emissions data to address current regulatory issues, because EPA AP-42 cotton gin PM2.5 emission factors were limited. In addition, current EPA AP-42 emission factor quality ratings for cotton gin PM10 (particulate matter with nominal diameter less than or equal to 10 µm) data are questionable, being extremely low. The objective of this study was to characterize particulate emissions for combined lint cleaning systems from cotton gins across the cotton belt based on particle size distribution analysis of total particulate samples from EPA-approved stack sampling methods. Average measured PM2.5, PM6, and PM10 emission factors based on the mass and particle size analyses of EPA Method 17 total particulate filter and wash samples from three gins (9 total test runs) were 0.0032 kg/227-kg bale (0.0070 lb/500-lb bale), 0.032 kg/bale (0.071 lb/bale), and 0.060 kg/bale (0.131 lb/bale), respectively. The combined lint cleaning system particle size distributions were characterized by an average mass median diameter of 19.9 µm (aerodynamic equivalent diameter). Based on system average emission factors, the ratio of PM2.5 to total particulate was 1.50%, PM6 to total particulate was 15.3%, and PM10 to total particulate was 28.2%.
36
Perricone, Guido, Mattia Alemani, Jens Wahlström e Ulf Olofsson. "A proposed driving cycle for brake emissions investigation for test stand". Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 234, n. 1 (8 aprile 2019): 122–35. http://dx.doi.org/10.1177/0954407019841222.
Testo completoAbstract (sommario):
Particulate matter emission factors from vehicle brakes are difficult to assess directly from the field. Moreover, there is a lack of a standardized cycle and test stand for evaluating brake emissions. For these reasons, a test cycle was developed from real driving data collected from a car. This new test cycle was implemented on an inertia disc brake dynamometer appositely designed for brake particle emission studies. Results reveal that, for the brake system used as an example, the obtained emission factors for the urban driving conditions studied are comparable to EURO 6 regulations in terms of particle number and comparable to EURO 4 levels in terms of mass with brake emission factors equal to 4.37–6.46 × 1011 particles/km and 44–48 mg/km, respectively.
37
Pielecha, Jacek, e Jerzy Merkisz. "Selection of a Particulate Filter for a Gasoline-Powered Vehicle Engine in Static and Dynamic Conditions". Energies 16, n. 23 (26 novembre 2023): 7777. http://dx.doi.org/10.3390/en16237777.
Testo completoAbstract (sommario):
Current challenges in terms of exhaust emission limits are related to the reduction of the particle numbers in spark ignition direct injection engines. The article concerns the analysis of the thermodynamic parameters of engine operation, allowing the selection of the particulate filter configuration and its technical parameters. The designed system consisting of an internal combustion engine and an exhaust system with an exhaust gas treatment system should be sufficient to meet ecological requirements in the form of reducing particulate matter emissions. The analysis of particulate matter emissions for the system without a filter and with a filter installed in the engine exhaust system was carried out for the mass, number and dimensional distribution of particulate matter. The result was an assessment of filtration efficiency for the entire spectrum of particulate diameters in the identified engine operating ranges. As a result, it was found that the particulate filter used in the engine exhaust system effectively reduces the particle number due to the greater filtration efficiency of large particles. The summary of the work related to the analysis of the ecological parameters of a spark ignition engine with direct fuel injection was a simulation of road tests of a vehicle with the proposed modified vehicle exhaust system equipped with a particulate filter. For this configuration, the analysis of particulate number emissions in the parameterized engine operating areas showed that it is possible to meet the particulate number emission limits, and the obtained road emission results are fully acceptable in terms of the obtained absolute values.
38
Vogt, M., E. D. Nilsson, L. Ahlm, E. M. Mårtensson e C. Johansson. "The relationship between 0.25–2.5 μm aerosol and CO<sub>2</sub> emissions over a city". Atmospheric Chemistry and Physics Discussions 10, n. 9 (9 settembre 2010): 21521–45. http://dx.doi.org/10.5194/acpd-10-21521-2010.
Testo completoAbstract (sommario):
Abstract. Unlike exhaust emissions, non-exhaust traffic emissions are completely unregulated and there are large uncertainties in the non-exhaust emission factors required to estimate the emissions of these aerosols. This study provides the first published results of direct measurements of size resolved emission factors for particles in the size range 0.25–2.5 μm using a new approach deriving aerosol emission factors from the CO2 emission fluxes. Because the aerosol and CO2 emissions have a common source and because the CO2 emission per fuel or traffic amount are much less uncertain than the aerosol emissions, this approach has obvious advantages. Therefore aerosol fluxes were measured during one year using the eddy covariance method at the top of a 118 m high communication tower over Stockholm, Sweden. Maximum CO2 and particle fluxes coincides with the wind direction with densest traffic within the footprint area. Negative fluxes (uptake of CO2 and deposition of particles) coincides with an urban forest area. The fluxes of CO2 were used to obtain emission factors for particles by assuming that the CO2 fluxes could converted to amounts of fuel burnt. The estimated emission factors for the fleet mix in the measurement area are, in number 1.4×1011 [particle veh−1 km−1]. Assuming spherical particles of density 1600 kg/m3 this corresponds to 27.5 mg veh−1 km−1. Wind speed influence the emission factor indicating that wind induced turbulence may be important.
39
ŠARKAN, Branislav, Michal LOMAN, Ondrej STOPKA, Jacek CABAN e Arkadiusz MAŁEK. "Quantifying the Volume of Particulate Matter at Bus Stations". Promet - Traffic&Transportation 37, n. 1 (6 febbraio 2025): 19–35. https://doi.org/10.7307/ptt.v37i1.675.
Testo completoAbstract (sommario):
Congested urban traffic substantially contributes to air pollution in cities. While waiting at bus stops, passengers may be exposed to increased contamination caused by vehicles, including particulate matter (PM). The modern bus stop layout, position and design ignore air quality and allow excessive exposure to pollution. Particulate matter seriously harms the environment, threatening human health and severely damaging all living organisms. The research purpose is to monitor particle emissions at the bus station in the city of Žilina (Slovakia), amassing data on exhaust emissions released from buses at the station premises. As moving or running-engine vehicles incessantly produce atmospheric emissions, we measure air quality during peak hours at the bus station. The results indicate a direct interconnection between passing vehicles and produced particle emissions, when multiple times higher emission levels are revealed. During the morning rush hour, the particulate matter exceeded 360% for PM2.5 and 420% for PM10. The research showed PM released directly from the buses tends to accumulate in covered premises of the bus station, severely damaging the health of passengers and staff. Our study warns about possible risks of deteriorating human health as waiting passengers unknowingly inhale contaminated particles. Our results indicate the largest emission producers and suggest remedial measures.
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Lauenburg, Marvin, Matthias Karl, Volker Matthias, Markus Quante e Martin Ramacher. "City Scale Modeling of Ultrafine Particles in Urban Areas with Special Focus on Passenger Ferryboat Emission Impact". Toxics 10, n. 1 (21 dicembre 2021): 3. http://dx.doi.org/10.3390/toxics10010003.
Testo completoAbstract (sommario):
Air pollution by aerosol particles is mainly monitored as mass concentrations of particulate matter, such as PM10 and PM2.5. However, mass-based measurements are hardly representative for ultrafine particles (UFP), which can only be monitored adequately by particle number (PN) concentrations and are considered particularly harmful to human health. This study examines the dispersion of UFP in Hamburg city center and, in particular, the impact of passenger ferryboats by modeling PN concentrations and compares concentrations to measured values. To this end, emissions inventories and emission size spectra for different emission sectors influencing concentrations in the city center were created, explicitly considering passenger ferryboat traffic as an additional emission source. The city-scale chemical transport model EPISODE-CityChem is applied for the first time to simulate PN concentrations and additionally, observations of total particle number counts are taken at four different sampling sites in the city. Modeled UFP concentrations are in the range of 1.5–3 × 104 cm−3 at ferryboat piers and at the road traffic locations with particle sizes predominantly below 50 nm. Urban background concentrations are at 0.4–1.2 × 104 cm−3 with a predominant particle size in the range 50–100 nm. Ferryboat traffic is a significant source of emissions near the shore along the regular ferry routes. Modeled concentrations show slight differences to measured data, but the model is capable of reproducing the observed spatial variation of UFP concentrations. UFP show strong variations in both space and time, with day-to-day variations mainly controlled by differences in air temperature, wind speed and wind direction. Further model simulations should focus on longer periods of time to better understand the influence of meteorological conditions on UFP dynamics.
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Keita, Sekou, Cathy Liousse, Véronique Yoboué, Pamela Dominutti, Benjamin Guinot, Eric-Michel Assamoi, Agnès Borbon et al. "Particle and VOC emission factor measurements for anthropogenic sources in West Africa". Atmospheric Chemistry and Physics 18, n. 10 (1 giugno 2018): 7691–708. http://dx.doi.org/10.5194/acp-18-7691-2018.
Testo completoAbstract (sommario):
Abstract. A number of campaigns have been carried out to establish the emission factors of pollutants from fuel combustion in West Africa, as part of work package 2 (“Air Pollution and Health”) of the DACCIWA (Dynamics-Aerosol-Chemistry-Cloud Interactions in West Africa) FP7 program. Emission sources considered here include wood (hevea and iroko) and charcoal burning, charcoal making, open trash burning, and vehicle emissions, including trucks, cars, buses and two-wheeled vehicles. Emission factors of total particulate matter (TPM), elemental carbon (EC), primary organic carbon (OC) and volatile organic compounds (VOCs) have been established. In addition, emission factor measurements were performed in combustion chambers in order to reproduce field burning conditions for a tropical hardwood (hevea), and obtain particulate emission factors by size (PM0.25, PM1, PM2.5 and PM10). Particle samples were collected on quartz fiber filters and analyzed using gravimetric method for TPM and thermal methods for EC and OC. The emission factors of 58 VOC species were determined using offline sampling on a sorbent tube. Emission factor results for two species of tropical hardwood burning of EC, OC and TPM are 0.98 ± 0.46 g kg−1 of fuel burned (g kg−1), 11.05 ± 4.55 and 41.12 ± 24.62 g kg−1, respectively. For traffic sources, the highest emission factors among particulate species are found for the two-wheeled vehicles with two-stroke engines (2.74 g kg−1 fuel for EC, 65.11 g kg−1 fuel for OC and 496 g kg−1 fuel for TPM). The largest VOC emissions are observed for two-stroke two-wheeled vehicles, which are up to 3 times higher than emissions from light-duty and heavy-duty vehicles. Isoprene and monoterpenes, which are usually associated with biogenic emissions, are present in almost all anthropogenic sources investigated during this work and could be as significant as aromatic emissions in wood burning (1 g kg−1 fuel). EC is primarily emitted in the ultrafine fraction, with 77 % of the total mass being emitted as particles smaller than 0.25 µm. The particles and VOC emission factors obtained in this study are generally higher than those in the literature whose values are discussed in this paper. This study underlines the important role of in situ measurements in deriving realistic and representative emission factors.
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He, Xiaojia, Lillie Marie Barnett, Jennifer Jeon, Qian Zhang, Saeed Alqahtani, Marilyn Black, Jonathan Shannahan e Christa Wright. "Real-Time Exposure to 3D-Printing Emissions Elicits Metabolic and Pro-Inflammatory Responses in Human Airway Epithelial Cells". Toxics 12, n. 1 (13 gennaio 2024): 67. http://dx.doi.org/10.3390/toxics12010067.
Testo completoAbstract (sommario):
Three-dimensional (3D) printer usage in household and school settings has raised health concerns regarding chemical and particle emission exposures during operation. Although the composition of 3D printer emissions varies depending on printer settings and materials, little is known about the impact that emissions from different filament types may have on respiratory health and underlying cellular mechanisms. In this study, we used an in vitro exposure chamber system to deliver emissions from two popular 3D-printing filament types, acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA), directly to human small airway epithelial cells (SAEC) cultured in an air–liquid interface during 3D printer operation. Using a scanning mobility particle sizer (SMPS) and an optical particle sizer (OPS), we monitored 3D printer particulate matter (PM) emissions in terms of their particle size distribution, concentrations, and calculated deposited doses. Elemental composition of ABS and PLA emissions was assessed using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX). Finally, we compared the effects of emission exposure on cell viability, inflammation, and metabolism in SAEC. Our results reveal that, although ABS filaments emitted a higher total concentration of particles and PLA filaments emitted a higher concentration of smaller particles, SAEC were exposed to similar deposited doses of particles for each filament type. Conversely, ABS and PLA emissions had distinct elemental compositions, which were likely responsible for differential effects on SAEC viability, oxidative stress, release of inflammatory mediators, and changes in cellular metabolism. Specifically, while ABS- and PLA-emitted particles both reduced cellular viability and total glutathione levels in SAEC, ABS emissions had a significantly greater effect on glutathione relative to PLA emissions. Additionally, pro-inflammatory cytokines including IL-1β, MMP-9, and RANTES were significantly increased due to ABS emissions exposure. While IL-6 and IL-8 were stimulated in both exposure scenarios, VEGF was exclusively increased due to PLA emissions exposures. Notably, ABS emissions induced metabolic perturbation on amino acids and energy metabolism, as well as redox-regulated pathways including arginine, methionine, cysteine, and vitamin B3 metabolism, whereas PLA emissions exposures caused fatty acid and carnitine dysregulation. Taken together, these results advance our mechanistic understanding of 3D-printer-emissions-induced respiratory toxicity and highlight the role that filament emission properties may play in mediating different respiratory outcomes.
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Fink, Lea, Matthias Karl, Volker Matthias, Andreas Weigelt, Matti Irjala e Pauli Simonen. "Using the Multicomponent Aerosol FORmation Model (MAFOR) to Determine Improved VOC Emission Factors in Ship Plumes". Toxics 12, n. 6 (14 giugno 2024): 432. http://dx.doi.org/10.3390/toxics12060432.
Testo completoAbstract (sommario):
International shipping’s particulate matter primary emissions have a share in global anthropogenic emissions of between 3% and 4%. Ship emissions of volatile organic compounds (VOCs) can play an important role in the formation of fine particulate matter. Using an aerosol box model for the near-plume scale, this study investigated how the changing VOC emission factor (EF) for ship engines impacts the formation of secondary PM2.5 in ship exhaust plumes that were detected during a measurement campaign. The agreement between measured and modeled particle number size distribution was improved by adjusting VOC emissions, in particular of intermediate-, low-, and extremely low-volatility compounds. The scaling of the VOC emission factor showed that the initial emission factor, based on literature data, had to be multiplied by 3.6 for all VOCs. Information obtained from the box model was integrated into a regional-scale chemistry transport model (CTM) to study the influence of changed VOC ship emissions over the Mediterranean Sea. The regional-scale CTM run with adjusted ship emissions indicated a change in PM2.5 of up to 5% at the main shipping routes and harbor cities in summer. Nevertheless, overall changes due to a change in the VOC EF were rather small, indicating that the size of grid cells in CTMs leads to a fast dilution.
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Pirjola, L., A. Pajunoja, J. Walden, J. P. Jalkanen, T. Rönkkö, A. Kousa e T. Koskentalo. "Mobile measurements of ship emissions in two harbour areas in Finland". Atmospheric Measurement Techniques Discussions 6, n. 4 (5 agosto 2013): 7149–84. http://dx.doi.org/10.5194/amtd-6-7149-2013.
Testo completoAbstract (sommario):
Abstract. Four measurement campaigns by a mobile laboratory van were performed in two different environments; inside the harbour areas in the city center of Helsinki and along the narrow shipping channel near the city of Turku, Finland, during the winter and summer conditions in 2010–2011. The characteristics of gaseous (CO, CO2, SO2, NO, NO2, NOx) and particulate (number and volume size distributions as well as PM2.5) emissions for 11 ships regularly operating on the Baltic Sea were studied to determine the emission parameters. The highest particle concentrations were 1.5 × 106 and 1.6 × 105 cm−3 in Helsinki and Turku, respectively, and the particle number size distributions had two modes. The dominating mode was peaking at 20–30 nm and the accumulation mode at 80–100 nm. The majority of the particle mass was volatile since after heating the sample to 265 °C, the particle volume of the studied ships decreased by around 70%. The emission factors for NOx varied in the range of 25–100 g (kg fuel)−1, for SO2 in the range of 2.5–17.0 g (kg fuel)−1, for particle number in the range of (0.32–2.26) × 1016 particles (kg fuel)−1, and for PM2.5 between 1.0–4.9 g (kg fuel)−1. The ships equipped with SCR had lowest NOx emissions whereas the ships with DWI and HAM had lowest SO2 emissions but highest particulate emissions. For all ships the averaged fuel sulphur contents (FSCs) were less than 1% (by mass) but none of those was below 0.1% which will be the new EU directive from 1 January 2015 in the SOx Emission Control Areas, indicating big challenges for ships operating on the Baltic Sea.
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Su, Penghao, Hanzhe Zhang, Liming Peng, Lihong Zhu, Tie Li, Xiaojia Tang e Yimin Zhu. "Particulate Matter (PM) and Parent, Nitrated and Oxygenated Polycyclic Aromatic Hydrocarbon (PAH) Emissions of Emulsified Heavy Fuel Oil in Marine Low-Speed Main Engine". Toxics 12, n. 6 (31 maggio 2024): 404. http://dx.doi.org/10.3390/toxics12060404.
Testo completoAbstract (sommario):
To understand the influences of emulsified fuel on ship exhaust emissions more comprehensively, the emissions of particulate matter (PM), nitrated, oxygenated and parent polycyclic aromatic hydrocarbons (PAHs) were studied on a ship main engine burning emulsified heavy fuel oil (EHFO) and heavy fuel oil (HFO) as a reference. The results demonstrate that EHFO (emulsified heavy fuel oil) exhibits notable abilities to significantly reduce emissions of particulate matter (PM) and low molecular weight PAHs (polycyclic aromatic hydrocarbons) in the gas phase, particularly showcasing maximum reductions of 13.99% and 40.5%, respectively. Nevertheless, burning EHFO could increase the emission of high molecular weight PAHs in fine particles and pose a consequent higher carcinogenic risk for individual particles. The total average (gaseous plus particulate) ΣBEQ of EHFO exhausts (41.5 μg/m3) was generally higher than that of HFO exhausts (18.7 μg/m3). Additionally, the combustion of EHFO (extra-heavy fuel oil) can significantly alter the emission quantity, composition, and particle-size distribution of PAH derivatives. These changes may be linked to molecular structures, such as zigzag configurations in C=O bonds. Our findings may favor the comprehensive environmental assessments on the onboard application of EHFO.
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Bermúdez, Vicente, Santiago Ruiz, Ricardo Novella e Lian Soto. "Effects of multiple injection strategies on gaseous emissions and particle size distribution in a two-stroke compression-ignition engine operating with the gasoline partially premixed combustion concept". Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 233, n. 10 (5 ottobre 2018): 2650–68. http://dx.doi.org/10.1177/0954407018802960.
Testo completoAbstract (sommario):
In order to improve performance of internal combustion engines and meet the requirements of the new pollutant emission regulations, advanced combustion strategies have been investigated. The newly designed partially premixed combustion concept has demonstrated its potential for reducing NOx and particulate matter emissions combined with high indicated efficiencies while still retaining proper control over combustion process by using different injection strategies. In this study, parametric variations of injection pressure, second injection and third injection timings were experimentally performed to analyze the effect of the injection strategy over the air/fuel mixture process and its consequent impact on gaseous compound emissions and particulate matter emissions including its size distribution. Tests were carried out on a newly designed two-stroke high-speed direct injection compression-ignition engine operating with the partially premixed combustion concept using 95 research octane number gasoline fuel. A scanning particle sizer was used to measure the particles size distribution and the HORIBA 7100DEGR gas analyzer system to determine gaseous emissions. Three different steady-state operation modes in terms of indicated mean effective pressure and engine speed were investigated: 3.5 bar indicated mean effective pressure and 2000 r/min, 5.5 bar indicated mean effective pressure and 2000 r/min, and 5.5 bar indicated mean effective pressure and 2500 r/min. The experimental results confirm how the use of an adequate injection strategy is indispensable to obtain low exhaust emissions values and a balance between the different pollutants. With the increase in the injection pressure and delay in the second injection, it was possible to obtain a trade-off between NOx and particulate matter emission reduction, while there was an increase in hydrocarbon and carbon monoxide emissions under these conditions. In addition, the experiments showed an increase in particle number emissions and a progressive shift in the particles size distribution toward larger sizes, increasing the accumulation-mode particles and reducing the nucleation-mode particles with the decrease in the injection pressure and delay in the third injection.
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Mathissen, Marcel, Theodoros Grigoratos, Tero Lahde e Rainer Vogt. "Brake Wear Particle Emissions of a Passenger Car Measured on a Chassis Dynamometer". Atmosphere 10, n. 9 (17 settembre 2019): 556. http://dx.doi.org/10.3390/atmos10090556.
Testo completoAbstract (sommario):
Brake wear emissions with a special focus on particle number (PN) concentrations were investigated during a chassis dynamometer measurement campaign. A recently developed, well-characterized, measurement approach was applied to measure brake particles in a semi-closed vehicle setup. Implementation of multiple particle measurement devices allowed for simultaneous measurement of volatile and solid particles. Estimated PN emission factors for volatile and solid particles differed by up to three orders of magnitude with an estimated average solid particle emission factor of 3∙109 # km−1 brake−1 over a representative on-road brake cycle. Unrealistic high brake temperatures may occur and need to be ruled out by comparison with on-road temperature measurements. PN emissions are strongly temperature dependent and this may lead to its overestimation. A high variability for PN emissions was found when volatile particles were not removed. Volatiles were observed under high temperature conditions only which are not representative of normal driving conditions. The coefficient of variation for PN emissions was 1.3 without catalytic stripper and 0.11 with catalytic stripper. Investigation of non-braking sections confirmed that particles may be generated at the brake even if no brakes are applied. These “off-brake-event” emissions contribute up to about 30% to the total brake PM10 emission.
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Peters, K., P. Stier, J. Quaas e H. Graßl. "Aerosol indirect effects from shipping emissions: sensitivity studies with the global aerosol-climate model ECHAM-HAM". Atmospheric Chemistry and Physics Discussions 12, n. 3 (8 marzo 2012): 7073–123. http://dx.doi.org/10.5194/acpd-12-7073-2012.
Testo completoAbstract (sommario):
Abstract. In this study, we employ the global aerosol-climate model ECHAM-HAM to globally assess aerosol indirect effects (AIEs) resulting from shipping emissions of aerosols and aerosol precursor gases. We implement shipping emissions of sulphur dioxide (SO2), black carbon (BC) and particulate organic matter (POM) for the year 2000 into the model and quantify the model's sensitivity towards uncertainties associated with the emission parameterisation as well as with the shipping emissions themselves. Sensitivity experiments are designed to investigate (i) the uncertainty in the size distribution of emitted particles, (ii) the uncertainty associated with the total amount of emissions, and (iii) the impact of reducing carbonaceous emissions from ships. We use the results from one sensitivity experiment for a detailed discussion of shipping-induced changes in the global aerosol system as well as the resulting impact on cloud properties. From all sensitivity experiments, we find AIEs from shipping emissions to range from −0.07 ± 0.01 W m−2 to −0.32 ± 0.01 W m−2 (global mean value and inter-annual variability as a standard deviation). The magnitude of the AIEs depends much more on the assumed emission size distribution and subsequent aerosol microphysical interactions than on the magnitude of the emissions themselves. It is important to note that although the strongest estimate of AIEs from shipping emissions in this study is relatively large, still much larger estimates have been reported in the literature before on the basis of modelling studies. We find that omitting just carbonaceous particle emissions from ships favours new particle formation in the boundary layer. These newly formed particles contribute just about as much to the CCN budget as the carbonaceous particles would, leaving the globally averaged AIEs nearly unaltered compared to a simulation including carbonaceous particle emissions from ships.
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Peters, K., P. Stier, J. Quaas e H. Graßl. "Aerosol indirect effects from shipping emissions: sensitivity studies with the global aerosol-climate model ECHAM-HAM". Atmospheric Chemistry and Physics 12, n. 13 (13 luglio 2012): 5985–6007. http://dx.doi.org/10.5194/acp-12-5985-2012.
Testo completoAbstract (sommario):
Abstract. In this study, we employ the global aerosol-climate model ECHAM-HAM to globally assess aerosol indirect effects (AIEs) resulting from shipping emissions of aerosols and aerosol precursor gases. We implement shipping emissions of sulphur dioxide (SO2), black carbon (BC) and particulate organic matter (POM) for the year 2000 into the model and quantify the model's sensitivity towards uncertainties associated with the emission parameterisation as well as with the shipping emissions themselves. Sensitivity experiments are designed to investigate (i) the uncertainty in the size distribution of emitted particles, (ii) the uncertainty associated with the total amount of emissions, and (iii) the impact of reducing carbonaceous emissions from ships. We use the results from one sensitivity experiment for a detailed discussion of shipping-induced changes in the global aerosol system as well as the resulting impact on cloud properties. From all sensitivity experiments, we find AIEs from shipping emissions to range from −0.32 ± 0.01 W m−2 to −0.07 ± 0.01 W m−2 (global mean value and inter-annual variability as a standard deviation). The magnitude of the AIEs depends much more on the assumed emission size distribution and subsequent aerosol microphysical interactions than on the magnitude of the emissions themselves. It is important to note that although the strongest estimate of AIEs from shipping emissions in this study is relatively large, still much larger estimates have been reported in the literature before on the basis of modelling studies. We find that omitting just carbonaceous particle emissions from ships favours new particle formation in the boundary layer. These newly formed particles contribute just about as much to the CCN budget as the carbonaceous particles would, leaving the globally averaged AIEs nearly unaltered compared to a simulation including carbonaceous particle emissions from ships.
50
BINAY, Emrullah, Cem ONAL, Armağan ONAL e Evrim Kepekci TEKKELI. "Pharmacokinetic analysis of febuxostat in human serum by UFLC based on fluorimetric derivatization". Revue Roumaine de Chimie 68, n. 10-12 (8 febbraio 2024): 527–32. http://dx.doi.org/10.33224/rrch.2023.68.10-12.04.
Testo completoAbstract (sommario):
An ultra fast liquid chromatographic (UFLC) method using fluorimetric detection for the quantitation of Febuxostat (FEB) in human serum was developed by precolumn derivatization with 4-bromomethyl-7-methoxy coumarin (BrMmC). The derivatization was catalyzed with dibenzo-18-crown-6-ether to produce a fluorescent derivative which was determined through fluorescence measurement with excitation at 320 nm and emission at 395 nm wavelengths. A C18 column with 100 cm x 4.6 mm, 3 µm particule size was used for the UFLC separation procedure. A mixture of acetonitrile: methanol: 0.05 M aqueous ammonium acetate (pH 5.0) (40:40:20, v/v/v) was used as mobile phase. During the procedure, the flow rate was maintained at 0.5 mL/min. A calibration curve was then plotted as 0.005–3.0 µg/mL with a detection limit of 0.0022 µg/mL and quantification limit of 0.0073 µg/mL. The mean recovery to reveal the accuracy and relative standard deviation (RSD) that indicates the precision of the method were found out to be 85.20 % and less than 3.52 %, respectively. The utility of the new method has been demonstrated by measuring the pharmacokinetics of FEB by administration of 80 mg tablets to a healthy female volunteer, aged 42.