In this research the benefits of applying oxy-combustion in a diesel engine to reduce NOx and particulate emissions were evaluated. The addition of oxygen to the intake in conjunction with exhaust gas recirculation (EGR) was shown to reduce NOx without an increase in particulate. Indicated specific NOx and particulate emissions for oxygen-enhanced EGR (O-EGR) and EGR without oxygen addition (normal or N-EGR) were compared at three engine loads. NOx emissions correlated with flame temperature for both N-EGR and O-EGR but were slightly lower at a given flame temperature for O-EGR. Flame temperature reduction for N-EGR was primarily through dilution of the available oxygen while for O-EGR both the increase of specific heat and dilution were important in reducing flame temperature. Oxygen addition allowed the use of high levels of EGR without reducing the oxygen concentration, thereby substituting CO2 and H2O for a substantial portion of the N2 as diluent. Increased dissociation due to higher levels of CO2 was believed to provide a minor enhancement to flame temperature reduction for O-EGR. An analysis of NOx formation based on the Zeldovich mechanism suggested that increased NOx reduction for O-EGR at equivalent flame temperatures is due to lower nitrogen concentrations. Indicated specific particulate increased with increasing EGR for N-EGR and correlated with flame temperature but remained constant for O-EGR and did not correlate with flame temperature. This indicated that O-EGR has a chemical effect on particulate formation and/or oxidation. The literature suggests CO2 suppresses soot formation by decreasing the radical H concentration which reduces the formation of soot precursors and soot growth.

[pt] Neste trabalho foi feita a quantificação e a caracterização química de material particulado (PM, do inglês particulate matter), com foco no material particulado grosso (PM10) coletado em quatro diferentes locais da região metropolitana do Rio de Janeiro (Gericinó, Zona Oeste; Duque de Caxias, Baixada Fluminense; Bonsucesso, Zona Norte e Centro- região central da cidade), utilizando amostradores de grande volume e filtros de fibra de vidro fornecidos pelo Instituto Estadual do Ambiente (INEA). Utilizando filtros ao longo do ano de 2019, foram feitas análises em Cromatógrafo de íons (CI) e espectrometria de massas com plasma indutivamente acoplado (ICP-MS) para a caracterização das amostras e quantificação de íons e metais. Também foi feita avaliação de concentração de PM10 sob influência da precipitação ao longo de 10 anos de estudo (2010 a 2019) e os níveis comparados com os valores recomendados pelo CONAMA. Para complementar o estudo foi realizado um levantamento bibliográfico sobre poluição veicular relacionada ao PM10 no Brasil. Os resultados apontam para um aumento nos níveis de PM10 ao longo da década avaliada, principalmente na região de Bonsucesso, com concentrações médias de 62 (micro)g m-3 , em alguns casos ultrapassando os limites do CONAMA. Com relação á precipitação, houve diferença significativa estatisticamente em dias sob ocorrência de chuva e dias sob ausência de chuva. Os íons que apresentaram as maiores concentrações foram NO3 - , SO4 2- e Na+ com concentrações médias variando de 2,6-3,4; 3,0- 3,3; 2,4- 3,0 (micro)g m-3, respectivamente, em todas as estações do estudo. A análise dos metais definiu Fe e Cu como os metais em maior concentração nas amostras, com concentrações médias variando de 0,54 a 0,73 e de 0,023 a 0,047 (micro)g m-3 , respectivamente. Tais resultados são reforçados pela análise de Black carbon através de absorção ótica, que reportou uma concentração média variando de 3,6 a 6,0 (micro)g m-3 . A região de Bonsucesso revelou ser a que apresentou as maiores concentrações para os parâmetros supracitados, confirmando a influência do maior tráfego veicular reportado para a região. / [en] In this work, the quantification and chemical characterization of particulate matter (PM) was carried out, focusing on coarse particulate matter (PM10) collected in four different locations in the metropolitan region of Rio de Janeiro (Gericinó, West Zone; Duque de Caxias, Baixada Fluminense; Bonsucesso, North Zone and Center-central region of the city), employing large volume samplers and fiberglass filters, supplied by the State Institute of the Environment (INEA). Using filters throughout 2019, analyzes were carried out in Ion Chromatograph (IC) and inductively coupled plasma mass spectrometry (ICP-MS) for the characterization of the samples and quantification of ions and metals. An evaluation of PM10 concentration under the precipitation influence was also carried out over 10 years of study (2010 to 2019) and the levels compared with the values recommended by CONAMA. To complete the study, a bibliographic study on vehicular pollution related to PM10 in Brazil was implemented. The results point to an increase in PM10 levels over the evaluated decade, mainly in the Bonsucesso region, with average concentrations of 62 (micro)g m-3 , in some cases overreaching the limits of CONAMA. Concerning the precipitation, there was a statistically significant discrepancy in days with rain and days without rain. The ions that showed the highest concentrations were NO3 - , SO4 2- and Na+ with mean concentrations ranging from 2.6-3.4; 3.0-3.3; 2.4-3.0 (micro)g m-3 , respectively, in all groups of the study. The metal analysis defined Fe and Cu as the most represented metals in the samples, with mean concentrations ranging from 0.54 to 0.73 and from 0.023 to 0.047 (micro)g m3 , respectively. Such results are strengthened by the analysis of Black carbon through optical absorption, which reported an average concentration ranging from 3.6 to 6.0 (micro)g m-3 . The Bonsucesso region showed to be the one with the highest concentrations for the aforementioned parameters, confirming the influence of the greater vehicular traffic reported for the region.

Airborne particulate matter (PM) in urban areas is derived from a combination of natural and anthropogenic sources. To identify PM sources and their effects on air quality, we collected PM using active filter samplers over a two-year period in the urban Wasatch Front, northern Utah, an area affected by multiple pollution sources. Filters from active samplers and other PM samples were analyzed for major and trace element concentrations and 87Sr/86Sr ratios. We identified wind-blown mineral dust from dry lake beds, winter inversions, and fireworks as primary PM sources affecting air quality in the Wasatch Front. Dust contributes Al, Be, Ca, Co, Cs, Fe, Li, Mg, Mn, Rb, Th, U, Y, and REEs which are typical components of carbonate and silicate minerals. Winter inversions entrap As, Cd, Mo, Pb, Sb, Tl, and Zn from brake dust, combustion engine exhaust, and refining processes. Concentrations of common components of fireworks Ba, Cu, K, and Sr greatly increase (>4 times) during holidays. Strontium released from fireworks has a distinct 87Sr/86Sr ratio that dominates the isotopic composition of PM during holidays. Fireworks have 87Sr/86Sr ratios of <0.7080 compared with 0.7100 for Sevier Dry Lake and 0.7150 for Great Salt Lake lakebed. Sources of particulate matter vary seasonally. Dust events dominate the air quality signature during spring and summer while winter inversions occur from November through February. Transport of PM to mountain snowpack negatively affect water quality. This is the first study to describe variations in multiple PM sources and their potential health effects in Utah, USA

Yes / Air pollution has been integrated into global challenges over the last few years due to its negative impact on the health of human beings, increasing socio-economic risks and its contribution to climate change. This study attempts to evaluate the current status of Iran's air pollution with regard to the sources of emissions, control policies, as well as the health and climate consequences that have resulted through available data from monitoring stations reported in the literature, official documents and previous published papers. Many large cities in Iran surpass the permissible concentration of air pollutants, particularly particulate matter, sulfur dioxide, black carbon and ozone. Although regulations and policies are in place and enormous efforts are being made to address air pollution issues in the country, implementation and enforcement are not as effective as they could be. The significant challenges may be regarded as the inefficiency of regulation and supervision systems, the lack of air quality monitoring systems and technology, particularly in industrial cities rather than Tehran as well as the lack of continual feedback and investigations on the efficiency of regulation. Providing such an up-to-date report can bring opportunities for international collaboration, which is essential in addressing the air pollution worldwide. We suggest that a way forward could be more focused on conducting systematic reviews using scientometric methods to show an accurate picture and trend in air pollution and its association in Iran, implementing an integrated approach for both climate change and air pollution issues, collaborating with international counterparts to share knowledge, tools, and techniques.

Yes / Implementation of an intelligent powertrain health management relies on robust prognostics modelling. However, prognostics capability is often limited due to unknown future operating conditions, which varies with duty cycles and individual driver behaviours. On the other hand, the growing availability of data pertaining to vehicle usage allows advanced modelling of usage patterns and driver behavious, bringing optimisation opportunities for powertrain operation and health management. This paper introduces a methodology for driving behaviour modelling, underpinned by Machine Learning classification algorithms, generating model-based predictive insight for intelligent powertrain health management strategies. Specifically, the aim is to learn the patterns of driving behaviour and predict characteristics for the short-term future operating conditions as a basis for enhanced control strategies to optimise energy efficiency and system reliability. A case study of an automotive emissions aftertreatment system is used to comprehensively demonstrate the proposed framework. The case study illustrates the approach for integrating predictive insight from machine learning deployed on real world trip behaviour data, in conjunction with a reliability-based model of the operational behaviour of a particulate filter, to propose an intelligent active regeneration control strategy for improved efficiency and reliability performance. The effectiveness of the proposed strategy was demonstrated on an industry standard model-in-the-loop set up with a representative sample of real-world vehicle driving data. / The authors acknowledge funding for the research presented in this article from Jaguar Land Rover under a research collaboration with the University of Bradford on “Intelligent Personalised Powertrain Healthcare”, and the Institute of Digital Engineering who have provided funding for proof of concept – the aiR-FORCE project.

Rheological properties of idealised models which exhibit all the non-Newtonian flow phenomenology commonly seen in dense suspensions are investigated by particulate-dynamics computer-simulations. The objectives of these investigations are: (i) to establish the origins of various aspects of dense suspension rheology such as shear-thinning, shear thickening and dilatancy; (ii) to elucidate the different regions of a typical dense suspension rheogram by examining underlying structures and shear induced anisotropies in kinetic energy, diffusivity and pressure; (iii) to investigate the scaling of the simplest idealised model suspension; i.e. the hard-sphere model in Newtonian media and its relationship to the isokinetic flow curves obtained through non-equilibrium molecular dynamics (NEMD) simulations; (iv) to preliminarily determine the effect of perturbations present in all real colloidal suspensions, namely particle size polydispersity and a slight 'softness' of the interparticle potential. Non-equilibrium isokinetic simulations have been performed upon ;systems of particles interacting through the classical hard-sphere potential and a perturbation thereof, in which the hard-core is surrounded by a 'slightly soft' repulsive skin. The decision to base the present work upon isokinetic studies was made in order to obtain a better under- standing of suspension rheology by making a direct connection with previous NEMD studies of thermal systemst(93). These studies have shown that the non-linear behaviour exhibited by these systems under shear is atttributable to a shear-induced perturbation of the equilibrium phase behaviour. The present study shows this behaviour to correspond to the high shear region of the generalised suspension flow curve. / Science and Engineering Research Council and Unilever Research

[pt] O Réveillon em Copacabana, no Rio de Janeiro, na virada do dia 31/12 para o dia 01/01, ocorre com a queima de 17 a 25 t de fogos de artifícios com duração entre 12 a 17 minutos. Estudos realizados em outros países durante comemorações com queima de fogos mostram um aumento significativo de alguns poluentes no ar. Este estudo avaliou a qualidade do ar em Copacabana durante as comemorações do ano novo de 2015 a 2020, considerando as concentrações do MP10, SO2, CO e O3 amostrados na estação automática. Pelo teste de Shapiro-Wilk, uma distribuição assimétrica no banco de dados foi observada, e através do teste não paramétrico as concentrações diárias entre os dias 31 de dezembro e 01 de janeiro foram testadas. A composição química MP2,5 amostrado na estação semiautomática de Copacabana em 2019, foi realizada através das técnicas analíticas de cromatografia de íons (CI) e espectrometria de massa por plasma acoplado indutivamente (ICP-MS), traduzido do inglês, inductively coupled plasma mass spectrometry. Durante o ano de 2019, as concentrações diária e anual do MP(2,5) não ultrapassaram os padrões nacionais de qualidade do ar, mas segundo os padrões recomendados pela OMS, a qualidade do ar esteve inapropriada. As concentrações elementares e iônicas determinadas por ICP-MS e CI indicaram espécies características de fontes veiculares e naturais. Em 01 de janeiro de 2020 a concentração dos íons Cl(-) e Na(+), foi atribuída ao spray marinho, e a ausência dos ânions C2H3COO(-), CH2(COO)2(2-) CHOO(-) e C2O4(2-) foi atribuída à diminuição da circulação urbana. / [en] New Year s Eve in Copacabana, Rio de Janeiro, at the turn of 12/31 to 01/01, takes place with the burning of 17 to 25 t of fireworks lasting between 12 and 17 minutes. Studies carried out in other countries during celebrations with fireworks show a significant increase in some pollutants in the air. This study evaluated the air quality in Copacabana during the New Year celebrations from 2015 to 2020, considering the concentrations of PM10, SO2, CO and O3 sampled at the automatic station. By the Shapiro-Wilk test, an asymmetry distribution in the database was observed, and through the non-parametric test the daily concentrations between December 31st and January 1st were tested. The chemical composition PM2.5 sampled at the semi-automatic station in Copacabana in 2019 was performed using analytical techniques of ion chromatography (IC) and inductively coupled plasma mass spectrometry (ICP-MS). During the year 2019 concentrations of PM2.5 not exceeded to national air quality standards, but according to the standards recommended by the WHO, the air quality was inappropriate. The elemental and ionic concentrations determined by ICP-MS and CI indicated species characterized from vehicular and natural sources. On January 1, 2020, the concentration ions of Cl(-)and Na(+) was attributed to marine spray, and the absence of the anions C2H3COO(-), CH2(COO)2(2-) CHOO(-) e C2O4(2-) was attributed to the lowest urban circulation.

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