FUNDAMENTALS ON EMISSION AND CONTROL OF TRACE METAL COMPOUNDS IN COMBUSTION PROCESSES

Clean Air ◽  
2004 ◽  
Vol 5 (3) ◽  
pp. 323-331
Author(s):  
Ichiro Naruse ◽  
Hong Yao ◽  
Hirofumi Minato ◽  
Noboru Saito ◽  
Tadanaga Kohama
Keyword(s):  
Trace Metal ◽  
Metal Compounds ◽  
Combustion Processes ◽  
And Control

scholarly journals Evaluation of equivalent black carbon source apportionment using observations from Switzerland between 2008 and 2018

2020 ◽  
Vol 13 (4) ◽  
pp. 1867-1885 ◽  
Author(s):  
Stuart K. Grange ◽  
Hanspeter Lötscher ◽  
Andrea Fischer ◽  
Lukas Emmenegger ◽  
Christoph Hueglin
Keyword(s):  
Particulate Matter ◽  
Black Carbon ◽  
Processing Technique ◽  
Monitoring Site ◽  
Atmospheric Pollutant ◽  
Diurnal Cycles ◽  
Legal Limits ◽  
Using Data ◽  
Combustion Processes ◽  
And Control

Abstract. Black carbon (BC) or soot is a constituent of particulate matter (PM) which is relevant for negative human health and climate effects, and despite the lack of direct legal limits, it is recognised as an important atmospheric pollutant to monitor, understand, and control. Aethalometers are instruments which continuously monitor BC by measuring absorption at a number of distinct wavelengths. If collocated elemental carbon (EC) observations are used to transform these values into BC mass, by convention, the result is named equivalent black carbon (EBC). BC emitted by different combustion processes has different optical absorption characteristics, and this can be used to apportion EBC mass into traffic (EBCTR) and woodburning (EBCWB) components with a data processing technique known as the aethalometer model. The aethalometer model was applied to six EBC monitoring sites across Switzerland (using data between 2008 and 2018) and was evaluated by investigating diurnal cycles, model coefficients, and ambient temperature dependence of the two EBC components. For one monitoring site, San Vittore, the aethalometer model failed to produce plausible outputs. The reason for this failure was likely due to a high load of freshly emitted wood smoke during the winter which should be thought of as a third distinct emission source. After model evaluation, the trend analysis indicated that EBCTR concentrations at the remaining five locations significantly decreased between 2008 and 2018. EBCWB also demonstrated significant decreases in most monitoring locations but not at a monitoring site south of the Alps with a high PM load sourced from biomass burning. Ratios of EBC and particulate matter with a diameter of less than 2.5 µm (PM2.5) suggested that EBC contributes 6 %–14 % of the PM2.5 mass in Switzerland. The aethalometer model is a useful data analysis procedure but can fail under certain conditions; thus, careful evaluation is required to ensure the method is robust and suitable in other locations.

scholarly journals Investigation of the K-Mg-Ca Sulfate System as Part of Monitoring Problematic Phase Formations in Renewable-Energy Power Plants

Energies ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 5366
Author(s):  
Fiseha Tesfaye ◽  
Daniel Lindberg ◽  
Mykola Moroz ◽  
Leena Hupa
Keyword(s):  
Renewable Energy ◽  
Power Plants ◽  
Alkali Metals ◽  
Wind Farms ◽  
Biomass Combustion ◽  
Term Operation ◽  
Binary Phase Diagrams ◽  
Combustion Processes ◽  
And Control

Besides the widely applied hydropower, wind farms and solar energy, biomass and municipal and industrial waste are increasingly becoming important sources of renewable energy. Nevertheless, fouling, slagging and corrosion associated with the combustion processes of these renewable sources are costly and threaten the long-term operation of power plants. During a high-temperature biomass combustion, alkali metals in the biomass fuel and the ash fusion behavior are the two major contributors to slagging. Ash deposits on superheater tubes that reduce thermal efficiency are often composed of complex combinations of sulfates and chlorides of Ca, Mg, Na, and K. However, thermodynamic databases involving all the sulfates and chlorides that would favor a better understanding and control of the problems in combustion processes related to fouling, slagging and corrosion are not complete. In the present work, thermodynamic properties including solubility limits of some phases and phase mixtures in the K2SO4-(Mg,Ca)SO4 system were reviewed and experimentally investigated. Based on the new and revised thermochemical data, binary phase diagrams of the K2SO4-CaSO4 and K2SO4-MgSO4 systems above 400 °C, which are of interest in the combustion processes of renewable-energy power plants, were optimized.

Combustion Characteristics of Dried Sewage Sludge and Control of Trace-Metal Emission

2005 ◽  
Vol 19 (6) ◽  
pp. 2298-2303 ◽  
Author(s):  
Hong Yao ◽  
Ichiro Naruse
Keyword(s):  
Sewage Sludge ◽  
Trace Metal ◽  
Combustion Characteristics ◽  
And Control

scholarly journals Fundamentals on Vaporization Behavior of Trace Metal Compounds at Different Atmospheres and Temperatures.

2002 ◽  
Vol 81 (4) ◽  
pp. 256-262 ◽  
Author(s):  
Hong YAO ◽  
Hirofumi MINATO ◽  
Iddi S.N MKILAHA ◽  
Ichiro NARUSE
Keyword(s):  
Trace Metal ◽  
Metal Compounds

Electrical aspects of aerosol formation and control

1968 ◽  
Vol 307 (1489) ◽  
pp. 195-208 ◽  
Keyword(s):  
Magnetic Fields ◽  
Aerosol Formation ◽  
Size Number ◽  
Combustion Processes ◽  
And Control

The particles or droplets of an aerosol are usually charged or can be induced to acquire charge. This makes possible their manipulation by electric and, to some extent, by magnetic fields, not only when they are already fully grown, but also during the process of their formation or disappearance. In this manner their size, number, trajectories, form and site of deposition can be varied within wide limits. These principles have been applied in some cases and are obviously potentially applicable to a great many more. My own researches are concerned with the physics of combustion processes, where such methods can be used to act on dispersions of fuel, solid products or intermediates, but extrapolations to other fields readily suggest themselves.

scholarly journals Permeation, regulation and control of expression of TRP channels by trace metal ions

2014 ◽  
Vol 467 (6) ◽  
pp. 1143-1164 ◽  
Author(s):  
Alexandre Bouron ◽  
Kirill Kiselyov ◽  
Johannes Oberwinkler
Keyword(s):  
Trace Metal ◽  
Metal Ions ◽  
Trp Channels ◽  
Trace Metal Ions ◽  
And Control ◽  
Control Of Expression

scholarly journals Evaluation of equivalent black carbon (EBC) source appointment using observations from Switzerland between 2008 and 2018

2019 ◽  
Author(s):  
Stuart K. Grange ◽  
Hanspeter Lötscher ◽  
Andrea Fischer ◽  
Lukas Emmenegger ◽  
Christoph Hueglin
Keyword(s):  
Black Carbon ◽  
Processing Technique ◽  
Monitoring Site ◽  
Atmospheric Pollutant ◽  
Particulate Filters ◽  
Diurnal Cycles ◽  
Legal Limits ◽  
Using Data ◽  
Combustion Processes ◽  
And Control

Abstract. Black carbon (BC) or soot is a constituent of particulate matter (PM) which is relevant for negative human health and climate effects, and despite the lack of legal limits, it is recognised as an important atmospheric pollutant to monitor, understand, and control. Aethalometers are instruments which continuously monitor BC by measuring absorption at a number of distinct wavelengths. If collocated elemental carbon (EC) observations are used to transform these values into BC mass, by convention, the result is named equivalent black carbon (EBC). BC emitted by different combustion processes have different optical absorption characteristics and this can be used to apportion EBC mass into traffic (EBCTR) and woodburning (EBCWB) components with a data processing technique known as the aethalometer model. The aethalometer model was applied to six EBC monitoring sites across Switzerland (using data between 2008 and 2018) and was evaluated by investigating diurnal cycles, model coefficients, and ambient temperature dependence of the two EBC components. For one monitoring site, San Vittore, the aethalometer model failed to produce plausible outputs. The reason for this failure was likely due to a high load of freshly emitted wood smoke during the winter which should be thought of as a third distinct emission source. After model evaluation, the trend analysis indicated that EBCTR concentrations at the remaining five locations significantly decreased between 2008 and 2018 illustrating the successful widespread installation of diesel particulate filters (DPF) within the vehicle fleet. EBCWB also demonstrated significant deceases in most monitoring locations, but not at a monitoring site south of the Alps with a high PM load sourced from biomass burning. This indicated that the management of woodburning has be ineffective at reducing BC emissions and concentrations for this, likely representative location. The EBC/PM2.5 ratios suggested that EBC contributes 6–13 % of the PM2.5 mass in Switzerland which is important for soot and PM source management. The aethalometer model is a useful data analysis procedure, but can fail under certain conditions, thus, careful evaluation is required to ensure the method is robust and suitable in other locations.

scholarly journals Petrobactin Is Exported from Bacillus anthracis by the RND-Type Exporter ApeX

mBio ◽  
2017 ◽  
Vol 8 (5) ◽  
Author(s):  
A. K. Hagan ◽  
A. Tripathi ◽  
D. Berger ◽  
D. H. Sherman ◽  
P. C. Hanna
Keyword(s):  
Mass Spectrometry ◽  
Cell Division ◽  
Trace Metal ◽  
Bacillus Anthracis ◽  
Culture Media ◽  
Treatment Strategies ◽  
Ionization Mass ◽  
Critical Metal ◽  
And Control

ABSTRACT Bacillus anthracis—a Gram-positive, spore-forming bacterium—causes anthrax, a highly lethal disease with high bacteremia titers. Such rapid growth requires ample access to nutrients, including iron. However, access to this critical metal is heavily restricted in mammals, which requires B. anthracis to employ petrobactin, an iron-scavenging small molecule known as a siderophore. Petrobactin biosynthesis is mediated by asb gene products, and import of the iron-bound (holo)-siderophore into the bacterium has been well studied. In contrast, little is known about the mechanism of petrobactin export following its production in B. anthracis cells. Using a combination of bioinformatics data, gene deletions, and laser ablation electrospray ionization mass spectrometry (LAESI-MS), we identified a resistance-nodulation-cell division (RND)-type transporter, termed ApeX, as a putative petrobactin exporter. Deletion of apeX abrogated export of intact petrobactin, which accumulated inside the cell. However, growth of ΔapeX mutants in iron-depleted medium was not affected, and virulence in mice was not attenuated. Instead, petrobactin components were determined to be exported through a different protein, which enables iron transport sufficient for growth, albeit with a slightly lower affinity for iron. This is the first report to identify a functional siderophore exporter in B. anthracis and the in vivo functionality of siderophore components. Moreover, this is the first application of LAESI-MS to sample a virulence factor/metabolite directly from bacterial culture media and cell pellets of a human pathogen. IMPORTANCE Bacillus anthracis requires iron for growth and employs the siderophore petrobactin to scavenge this trace metal during infections. While we understand much about petrobactin biosynthesis and ferric petrobactin import, how apo-petrobactin (iron free) is exported remains unknown. This study used a combination of bioinformatics, genetics, and mass spectrometry to identify the petrobactin exporter. After screening 17 mutants with mutations of candidate exporter genes, we identified the apo-petrobactin exporter (termed ApeX) as a member of the resistance-nodulation-cell division (RND) family of transporters. In the absence of ApeX, petrobactin accumulates inside the cell while continuing to export petrobactin components that are capable of transporting iron. Thus, the loss of ApeX does not affect the ability of B. anthracis to cause disease in mice. This has implications for treatment strategies designed to target and control pathogenicity of B. anthracis in humans. IMPORTANCE Bacillus anthracis requires iron for growth and employs the siderophore petrobactin to scavenge this trace metal during infections. While we understand much about petrobactin biosynthesis and ferric petrobactin import, how apo-petrobactin (iron free) is exported remains unknown. This study used a combination of bioinformatics, genetics, and mass spectrometry to identify the petrobactin exporter. After screening 17 mutants with mutations of candidate exporter genes, we identified the apo-petrobactin exporter (termed ApeX) as a member of the resistance-nodulation-cell division (RND) family of transporters. In the absence of ApeX, petrobactin accumulates inside the cell while continuing to export petrobactin components that are capable of transporting iron. Thus, the loss of ApeX does not affect the ability of B. anthracis to cause disease in mice. This has implications for treatment strategies designed to target and control pathogenicity of B. anthracis in humans.

Sign in / Sign up

Export Citation Format

Share Document