The Physical and Chemical Character of Diesel Particulate Emissions-Measurement Techniques and Fundamental Considerations

1978 ◽  
Author(s):  
William H. Lipkea ◽  
John H. Johnson ◽  
Carl T. Vuk
Keyword(s):  
Measurement Techniques ◽  
Particulate Emissions ◽  
Diesel Particulate ◽  
Chemical Character ◽  
Physical And Chemical

The Morphology and Crystallography of Diesel Particulate Emissions

1981 ◽  
Vol 39 ◽  
pp. 148-149
Author(s):  
R. Stevenson
Keyword(s):  
Diffraction Pattern ◽  
Carbon Films ◽  
Particulate Emissions ◽  
Diesel Particulate ◽  
Amorphous Carbon Films ◽  
Turbostratic Carbon ◽  
Diesel Particles ◽  
Tem Mode ◽  
Exhaust Stream ◽  
Diffraction Patterns

A study has been made of the morphology and crystallography of particulate emissions from indirect injection diesel engines. This particulate matter consists substantially of carbon (although hydrocarbons can be extracted with solvents). Samples were collected in a diluted exhaust stream on amorphous carbon films and examined in a JEM-200C electron microscope operated in the TEM mode with an accelerating voltage of 200 KV.The morphology of the diesel particles, as shown in Fig. 1, markedly resembles carbon blacks and consists of an agglomeration of quasispherical subunits arranged in chains or clusters. Only limited changes in morphology were observed as the number of subunits in the particle increased (although larger particles tended to be more cluster-like than the extended chain shown in Fig. 1). However, a dramatic effect of the number of subunits was observed on the character of the diffraction pattern. Smaller particles yielded a diffraction pattern consisting of very diffuse rings typical of turbostratic carbon; the diffraction patterns from the larger particles, however, although qualitatively similar, exhibited much sharper and less diffuse ring patterns.

scholarly journals Examination of soil parameters based on the evaluation of the spectroradiometric reflectance characteristics of the topsoil

2014 ◽  
pp. 75-80
Author(s):  
Károly Bakos ◽  
Attila Dobos ◽  
János Nagy
Keyword(s):  
Measurement Techniques ◽  
Soil Surface ◽  
Soil Parameters ◽  
Surface Reflectance ◽  
Imaging Spectrometer ◽  
Top Soil ◽  
Multiple Samples ◽  
Physical And Chemical ◽  
Landscape Formation

In this article we are presenting the methodology applied to analyse and interpret the topsoil surface reflectance parameters of multiple samples collected in the Mugello valley area in northern Italy in October 2012. The main aim of the whole project was to discover geomorphological behaviour and situation of the area ino order to improve potential for correct dating of certain archaeological artefacts found in the nearby areas. One of the crucial problem researchers are facing in the area is the lack of understanding of the underlying geological and geomorphological processes that were describing and characterizing the area and that played important role not only in the current geography and landscape formation but also in the transportation of various sediments and artefacts. In this particular research the main aim is to examine the possibility of developing a quick way to assess low level properties of the soil using hand held spectrometer and rapid analysis of cross-section using in situ measurement techniques. In this work we collected over 2000 individual samples of topsoil surface reflectance properties that we organized into a spectral library. This library is then to be used to describe physical and chemical processes in the soil. To support the analysis results were compared to analysis results from different kind of assessments in the same area. Our results show a great potential of application of hand held imaging spectrometer in soil property analysis based on the top soil surface reflectance parameters.

Regeneration Characteristics of Diesel Particulate Filters Under Transient Exhaust Conditions

2005 ◽  
Author(s):  
M. Rizwan Khan ◽  
Tariq Shamim
Keyword(s):  
Steady State ◽  
Soot Oxidation ◽  
Effect Of Temperature ◽  
Particulate Emissions ◽  
Computational Investigation ◽  
Diesel Particulate ◽  
Diesel Particulate Filters ◽  
Particulate Filters ◽  
Fundamental Understanding ◽  
Careful Design

Particulate emissions from diesel engines, which have hazardous effects on living beings and environment, can be controlled by employing diesel particulate filters (DPFs). The DPF cleans the exhaust by physical trapping of the particulates. A major challenge in developing a DPF with wider applications is its lower durability. The filter durability may be increased by careful design of regeneration (soot oxidation) strategies. The regeneration characteristics of a DPF under steady state conditions are well known. However, during a typical driving cycle, a DPF is subjected to highly transient conditions due to changes in driving modes. These transients result in fluctuations of exhaust flow rate, gas composition and temperature. Such modulating exhaust conditions make the DPF performance and regeneration characteristics differ significantly from that under steady state conditions. The objective of this paper is to investigate the thermal and catalytic regeneration characteristics of DPF under transient exhaust conditions. In this work, a computational investigation is conducted to determine the effect of temperature and exhaust flow modulations on a DPF. The paper contributes to a better fundamental understanding of the filter’s performance under transient driving conditions.

Chemical and dispersal characteristics of particulate emissions from forest fires in Siberia

2012 ◽  
Vol 21 (7) ◽  
pp. 818 ◽  
Author(s):  
Y. N. Samsonov ◽  
V. A. Ivanov ◽  
D. J. McRae ◽  
S. P. Baker
Keyword(s):  
Particulate Matter ◽  
Forest Fires ◽  
Boreal Forests ◽  
Elemental Carbon ◽  
Particulate Emissions ◽  
Organic Substances ◽  
Forest Types ◽  
Chemical Parameters ◽  
Forest Fuels ◽  
Physical And Chemical

Approximately 20 experimental fires were conducted on forest plots of 1–4 ha each in 2000–07 in two types of boreal forests in central Siberia, and 18 on 6 × 12-m plots in 2008–10. These experiments were designed to mimic wildfires under similar burning conditions. The fires were conducted in prescribed conditions including full documentation on pre-fire weather, pre-fire and post-fire forest fuels, fire intensities, and other biological, physical and chemical parameters. The amount of particulate matter emitted during a typical fire averaged 0.6 t ha–1 and ranged within 0.2–1.0 t ha–1 depending on burning conditions. Particulates accounted for ~1–7% of the total mass of the consumed biomass during a typical forest fire (10–30 t ha–1 based on our data from 2000–07). Most of the particulate matter consists of organic substances, 77% on average, with a range of 70–90%. Elemental carbon averaged 8%, with a range of 2–18%. Trace element compositions and amounts of particulates indicate that there was no actual difference in the element emissions sampled from the fires conducted in the two forest types (6–8% in larch forest and 8% in pine forest). Most of the particulate matter, 90–95%, consists of submicrometre and near-micrometre particles ~0.1–5 μm in diameter.

Diesel particulate emissions and the implications for the soiling of buildings

1991 ◽  
Vol 11 (4) ◽  
pp. 243-254 ◽  
Author(s):  
Trudie Mansfield ◽  
Ron Hamilton ◽  
Bryan Ellis ◽  
Peter Newby
Keyword(s):  
Particulate Emissions ◽  
Diesel Particulate
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