scholarly journals An Overview on the Catalytic Materials Proposed for the Simultaneous Removal of NOx and Soot

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3551
Author(s):  
Lidia Castoldi
Keyword(s):  
Urban Areas ◽  
Alternative Fuels ◽  
Physical Space ◽  
Exhaust Emissions ◽  
Mitigation Measures ◽  
Particulate Filter ◽  
Lean Nox Trap ◽  
Simultaneous Removal ◽  
Vehicular Pollution ◽  
Catalytic Systems

Vehicular pollution has become a major problem in urban areas due to the exponential increase in the number of automobiles. Typical exhaust emissions, which include nitrogen oxides (NOx), hydrocarbons (HC), carbon monoxide (CO), soot, and particulate matter (PM), doubtless have important negative effects on the environment and human health, including cardiovascular effects such as cardiac arrhythmias and heart attacks, and respiratory effects such as asthma attacks and bronchitis. The mitigation measures comprise either the use of clean alternative fuels or the use of innovative technologies. Several existing emission control technologies have proven effective at controlling emissions individually, such as selective catalytic reduction (SCR) and lean NOx trap (LNT) to reduce NOx and diesel particulate filter (DPF) specifically for PM abatement. These after-treatment devices are the most profitable means to reduce exhaust emissions to acceptable limits (EURO VI norms) with very little or no impact on the engine performances. Additionally, the relative lack of physical space in which to install emissions-control equipment is a key challenge for cars, especially those of small size. For this reason, to reduce both volume and cost of the after-treatment devices integrated catalytic systems (e.g., a sort of a “single brick”) have been proposed, reducing both NOx and PM simultaneously. This review will summarize the currently reported materials for the simultaneous removal of NOx and soot, with particular attention to their nature, properties, and performances.

Problems of Development of Small and Medium Russian Towns

2019 ◽  
pp. 24-29
Author(s):  
V V. Kafidov ◽  
V. N. Filippov ◽  
I. P. Filippova
Keyword(s):  
Urban Development ◽  
Urban Areas ◽  
Negative Impact ◽  
Physical Space ◽  
Living Environment ◽  
Transport Infrastructure ◽  
Negative Effects ◽  
Conceptual Approach ◽  
Fundamental Factor ◽  
New Buildings

The presented study addresses the problems of development of small and medium towns in Russia. Aim. The study aims to examine a town as a socio-economic environment where its residents exist and as the fundamental factor for the development of society.Tasks. The authors identify key problems in the development of small and medium Russian towns, which interferes with the historical appearance and has a negative impact on the living environment.Methods. Problems in the development of small and medium towns in Russia are examined using theoretical methods: systematic approach, statistical analysis, social and philosophical analysis.Results. The study identifies the main negative effects of the existing model of development of small and medium Russian towns, such as destruction of their historical and cultural appearance, distortion of the overall architectural motif, increased load on communications, and congestion of the transport infrastructure.Conclusions. At the current stage, efficient development of small and medium towns in Russia is impossible within the framework of the existing infill development. This chaotic process cannot be stopped without a new conceptual approach and changes in the legislative and normative framework of urban development. The only factor that determines the boundaries of the existing approach to urban development is the lack of physical space for new buildings in urban areas. The authors formulate proposals that would help to solve the problems of development of small and medium towns in Russia. 

scholarly journals Ethanol/Gasoline Blends as Alternative Fuel in Last Generation Spark-Ignition Engines: A Review on CO and HC Engine Out Emissions

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 4034
Author(s):  
Paolo Iodice ◽  
Massimo Cardone
Keyword(s):  
Physicochemical Properties ◽  
Alternative Fuels ◽  
Experimental Studies ◽  
Alternative Fuel ◽  
Exhaust Emissions ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Spark Ignition Engines ◽  
The Impact

Among the alternative fuels existing for spark-ignition engines, ethanol is considered worldwide as an important renewable fuel when mixed with pure gasoline because of its favorable physicochemical properties. An in-depth and updated investigation on the issue of CO and HC engine out emissions related to use of ethanol/gasoline fuels in spark-ignition engines is therefore necessary. Starting from our experimental studies on engine out emissions of a last generation spark-ignition engine fueled with ethanol/gasoline fuels, the aim of this new investigation is to offer a complete literature review on the present state of ethanol combustion in last generation spark-ignition engines under real working conditions to clarify the possible change in CO and HC emissions. In the first section of this paper, a comparison between physicochemical properties of ethanol and gasoline is examined to assess the practicability of using ethanol as an alternative fuel for spark-ignition engines and to investigate the effect on engine out emissions and combustion efficiency. In the next section, this article focuses on the impact of ethanol/gasoline fuels on CO and HC formation. Many studies related to combustion characteristics and exhaust emissions in spark-ignition engines fueled with ethanol/gasoline fuels are thus discussed in detail. Most of these experimental investigations conclude that the addition of ethanol with gasoline fuel mixtures can really decrease the CO and HC exhaust emissions of last generation spark-ignition engines in several operating conditions.

scholarly journals A Comparison of Ethanol, Methanol, and Butanol Blending with Gasoline and Its Effect on Engine Performance and Emissions Using Engine Simulation

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1322
Author(s):  
Simeon Iliev
Keyword(s):  
Alternative Fuels ◽  
Fossil Fuels ◽  
Gasoline Engine ◽  
Engine Performance ◽  
Exhaust Emissions ◽  
Engine Simulation ◽  
Engine Model ◽  
Fuel Blends ◽  
Performance And Emissions ◽  
Blended Fuels

Air pollution, especially in large cities around the world, is associated with serious problems both with people’s health and the environment. Over the past few years, there has been a particularly intensive demand for alternatives to fossil fuels, because when they are burned, substances that pollute the environment are released. In addition to the smoke from fuels burned for heating and harmful emissions that industrial installations release, the exhaust emissions of vehicles create a large share of the fossil fuel pollution. Alternative fuels, known as non-conventional and advanced fuels, are derived from resources other than fossil fuels. Because alcoholic fuels have several physical and propellant properties similar to those of gasoline, they can be considered as one of the alternative fuels. Alcoholic fuels or alcohol-blended fuels may be used in gasoline engines to reduce exhaust emissions. This study aimed to develop a gasoline engine model to predict the influence of different types of alcohol-blended fuels on performance and emissions. For the purpose of this study, the AVL Boost software was used to analyse characteristics of the gasoline engine when operating with different mixtures of ethanol, methanol, butanol, and gasoline (by volume). Results obtained from different fuel blends showed that when alcohol blends were used, brake power decreased and the brake specific fuel consumption increased compared to when using gasoline, and CO and HC concentrations decreased as the fuel blends percentage increased.

GEOPHYSICAL MONITORING: NEW OPPORTUNITIES TO PRESERVE ARCHITECTURAL MONUMENTS AND GREEN DESIGN IN URBAN AREAS

2020 ◽  
Author(s):  
Zakhar Slepak
Keyword(s):  
Urban Areas ◽  
Negative Impact ◽  
Technical Condition ◽  
Green Design ◽  
World Heritage Site ◽  
Mitigation Measures ◽  
Operating Life ◽  
Geophysical Monitoring ◽  
Railway Systems ◽  
Geological Processes

A new geophysical prospecting technique developed by the author was effectively applied for these purposes in 1994–2005 within the architectural complex of the Kazan Kremlin, a UNESCO World Heritage Site. The author has developed and successfully employed a unique gravity monitoring technique consisting in independent measurements at set points and at certain time intervals in the architectural complex of the Kazan Kremlin. The results of the geophysical monitoring and geodetic surveys conducted in open areas and inside architectural monuments offer new opportunities in preserving ancient buildings. Because geophysical monitoring can identify the negative impact of active geological processes on foundations of buildings, mitigation measures can be taken in timely manner. However, because the Kazan Kremlin is a state historical and architectural museum reserve, another objective is to maintain its exterior and renovate its green design. The above technology can also be used to analyze the technical condition of high-rise buildings, industrial facilities, underground railway systems and other structures, and significantly prolong their operating life.

scholarly journals Impact of aftertreatment devices on primary emissions and secondary organic aerosol formation potential from in-use diesel vehicles: results from smog chamber experiments

2010 ◽  
Vol 10 (6) ◽  
pp. 16055-16109 ◽  
Author(s):  
R. Chirico ◽  
P. F. DeCarlo ◽  
M. F. Heringa ◽  
T. Tritscher ◽  
R. Richter ◽  
...  
Keyword(s):  
Urban Areas ◽  
Secondary Organic Aerosol ◽  
Organic Aerosol ◽  
Oxidation Catalyst ◽  
Particulate Filter ◽  
Exhaust Aftertreatment ◽  
Smog Chamber ◽  
Aerosol Formation ◽  
Diesel Particulate ◽  
Diesel Vehicles

Abstract. Diesel particulate matter (DPM) is a significant source of aerosol in urban areas and has been linked to adverse health effects. Although newer European directives have introduced increasingly stringent standards for primary PM emissions, gaseous organics emitted from diesel cars can still lead to large amounts of secondary organic aerosol (SOA) in the atmosphere. Here we present results from smog chamber investigations characterizing the primary organic aerosol (POA) and the corresponding SOA formation at atmospherically relevant concentrations for three in-use diesel vehicles with different exhaust aftertreatment systems. One vehicle lacked exhaust aftertreatment devices, one vehicle was equipped with a diesel oxidation catalyst (DOC) and the final vehicle used both a DOC and diesel particulate filter (DPF). The experiments presented here were obtained from the vehicles at conditions representative of idle mode, and for one car in addition at a speed of 60 km/h. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was used to measure the organic aerosol (OA) concentration and to obtain information on the chemical composition. For the conditions explored in this paper, primary aerosols from vehicles without a particulate filter consisted mainly of black carbon (BC) with a low fraction of organic matter (OM, OM/BC<0.5), while the subsequent aging by photooxidation resulted in a consistent production of SOA only for the vehicles without a DOC and with a deactivated DOC. After 5 h of aging ~80% of the total organic aerosol was on average secondary and the estimated "emission factor" for SOA was 0.23–0.56 g/kg fuel burned. In presence of both a DOC and a DPF, primary particles with a mobility diameter above 5 nm were 300±19 cm−3, and only 0.01 g SOA per kg fuel burned was produced within 5 h after lights on. The mass spectra indicate that POA was mostly a non-oxidized OA with an oxygen to carbon atomic ratio (O/C) ranging from 0.097 to 0.190. Five hours of oxidation led to a more oxidized OA with an O/C range of 0.208 to 0.369.

Should Cities Embrace Their Heat Islands as Shields from Extreme Cold?

2018 ◽  
Vol 57 (6) ◽  
pp. 1309-1320 ◽  
Author(s):  
Jiachuan Yang ◽  
Elie Bou-Zeid
Keyword(s):  
Urban Areas ◽  
Heat Waves ◽  
Anthropogenic Heat ◽  
Mitigation Measures ◽  
Cold Wave ◽  
Cold Waves ◽  
Heat Islands ◽  
Extreme Cold ◽  
Anthropogenic Modifications ◽  
Cool Roofs

AbstractThe higher temperature in cities relative to their rural surroundings, known as the urban heat island (UHI), is one of the most well documented and severe anthropogenic modifications of the environment. Heat islands are hazardous to residents and the sustainability of cities during summertime and heat waves; on the other hand, they provide considerable benefits in wintertime. Yet, the evolution of UHIs during cold waves has not yet been explored. In this study, ground-based observations from 12 U.S. cities and high-resolution weather simulations show that UHIs not only warm urban areas in the winter but also further intensify during cold waves by up to 1.32° ± 0.78°C (mean ± standard deviation) at night relative to precedent and subsequent periods. Anthropogenic heat released from building heating is found to contribute more than 30% of the UHI intensification. UHIs thus serve as shelters against extreme-cold events and provide benefits that include mitigating cold hazard and reducing heating demand. More important, simulations indicate that standard UHI mitigation measures such as green or cool roofs reduce these cold-wave benefits to different extents. Cities, particularly in cool and cold temperate climates, should hence revisit their policies to favor (existing) mitigation approaches that are effective only during hot periods.

Evolutionary Modeling of Routes: The Case of Road Design

2001 ◽  
Author(s):  
Ângela Guimarães Pereira
Keyword(s):  
Genetic Algorithms ◽  
Physical Space ◽  
Linear Structure ◽  
Search Space ◽  
Evaluation Methodology ◽  
Mitigation Measures ◽  
Evolutionary Modeling ◽  
Technical Parameters ◽  
The Road ◽  
Road Design

In this study a route is defined as the path that a linear structure or facility follows in the terrain. Linear structures comprise facilities such as roads, motorways, railways, pipelines, electrical power lines, and telephone cables, each of these structures requiring specific technical parameters in what concerns the geometry of the path and having different effects on the terrain they traverse. Amongst these structures, roads and motorways are the group that creates the greatest overall impact; accordingly Portuguese legislation requires an environmental impact assessment (EIA) process as part of the necessary licensing approval. Usually the alternative (or alternatives) that undergo the EIA process is justified in terms of technical and economical issues. The result is that if major environmental impacts are identified by the EIA study, a myriad of mitigation measures are proposed, very seldom the redesign of the path being carried out (Guimarães Pereira & Antunes, 1996). Preliminary studies that precede the implementation of these types of projects are technically detailed and often come together with economical feasibility studies, shelving environmental issues for later assessment. In the methodology proposed in this chapter a multidimensional evaluation methodology, multicriteria evaluation, will be combined with the robustness of a search methodology, genetic algorithms (GAs) to generate alternative road routes that take into consideration environmental, economical, technical, and social criteria. These criteria are referenced to the physical space where the road is to be placed and therefore this methodology is embedded into a geographic information system (GIS). Genetic algorithms are particularly attractive to apply to multi-modal problems, allowing the exploration of spatial features to eventually find “best compromise” alternatives because these algorithms proceed their search by maintaining a population of solutions, that they can simultaneously exploit for their efficiency.1 Moreover, the particular mixing mechanism provides the means to recombine solutions and explore the search space. The remainder of this chapter describes evolutionary modeling of road routes, in particular the coding onto a GA of the geometric algorithm that accounts for the technical aspects of motorway siting. The details of the implementation of the MCDA-GA methodology, running within the GIS GRASS 4.1 (Geographic Resources Analysis Support System) and its application to generate and evaluate alternative routes of a section of a Portuguese complementary itinerary (IC7) will be presented.

scholarly journals Integrate Weather Radar and Monitoring Devices for Urban Flooding Surveillance

Sensors ◽  
2019 ◽  
Vol 19 (4) ◽  
pp. 825 ◽  
Author(s):  
Shih-Yen Hsu ◽  
Tai-Been Chen ◽  
Wei-Chang Du ◽  
Jyh-Horng Wu ◽  
Shih-Chieh Chen
Keyword(s):  
Real Time ◽  
Urban Areas ◽  
Weather Radar ◽  
Water Levels ◽  
Mitigation Measures ◽  
Extreme Weather Events ◽  
Television System ◽  
Urban Flood ◽  
Flood Monitoring ◽  
Image Capturing

With the increase of extreme weather events, the frequency and severity of urban flood events in the world are increasing drastically. Therefore, this study develops ARMT (automatic combined ground weather radar and CCTV (Closed Circuit Television System) images for real-time flood monitoring), which integrates real-time ground radar echo images and automatically estimates a rainfall hotspot according to the cloud intensity. Furthermore, ARMT combines CCTV image capturing, analysis, and Fourier processing, identification, water level estimation, and data transmission to provide real-time warning information. Furthermore, the hydrograph data can serve as references for relevant disaster prevention, and response personnel may take advantage of them and make judgements based on them. The ARMT was tested through historical data input, which showed its reliability to be between 83% to 92%. In addition, when applied to real-time monitoring and analysis (e.g., typhoon), it had a reliability of 79% to 93%. With the technology providing information about both images and quantified water levels in flood monitoring, decision makers can quickly better understand the on-site situation so as to make an evacuation decision before the flood disaster occurs as well as discuss appropriate mitigation measures after the disaster to reduce the adverse effects that flooding poses on urban areas.

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