In this work, the synthetic hydroxyapatite (HAP) was studied using different preparation routes to decrease the crystal size and to study the temperature effect on the HAP nano-sized hydroxyapatite crystallization. X-ray diffraction (XRD) analysis indicated that all samples were composed by crystalline and amorphous phases . The sample with greater quantity of amorphous phase (40% of total mass) was studied. The nano-sized hydroxyapatite powder was heated and studied at 300, 500, 700, 900 and 1150 °C. All samples were characterized by XRD and their XRD patterns refined using the Rietveld method. The crystallites presented an anisotropic form, being larger in the [001] direction. It was observed that the crystallite size increased continuously with the heating temperature and the eccentricity of the ellipsoidal shape changed from 2.75 at 300 °C to 1.94, 1.43, 1.04 and 1.00 respectively at 500, 700, 900 and 1150 °C. In order to better characterize the morphology of the HAP the samples were also examined using atomic force microscopy (AFM), infrared spectrometry (IR) and thermogravimetric analysis (TGA).
In this work, the synthetic hydroxyapatite (HAP) was studied using different preparation routes to decrease the crystal size and to study the temperature effect on the HAP nano-sized hydroxyapatite crystallization. X-ray diffraction (XRD) analysis indicated that all samples were composed by crystalline and amorphous phases . The sample with greater quantity of amorphous phase (40% of total mass) was studied. The nano-sized hydroxyapatite powder was heated and studied at 300, 500, 700, 900 and 1150 °C. All samples were characterized by XRD and their XRD patterns refined using the Rietveld method. The crystallites presented an anisotropic form, being larger in the [001] direction. It was observed that the crystallite size increased continuously with the heating temperature and the eccentricity of the ellipsoidal shape changed from 2.75 at 300 °C to 1.94, 1.43, 1.04 and 1.00 respectively at 500, 700, 900 and 1150 °C. In order to better characterize the morphology of the HAP the samples were also examined using atomic force microscopy (AFM), infrared spectrometry (IR) and thermogravimetric analysis (TGA).
Objective: The objective of the study was to develop a simple, validated, and affordable visible spectrophotometric method for determination of
piperacillin (PIP) present in bulk and powder for injection formulation.
Methods: In the present method, cobalt thiocyanate (CTC) was used as a chromogenic reagent where it forms 2:1 ion pair complex at pH 2 with PIP
which is having secondary and tertiary amine groups.
Results: The formed bluish-green colored ion pair between PIP and CTC is quantitatively extractable into nitrobenzene with an absorption maximum of
665 nm. Regression analysis (r=0.9996) shows that the plotted calibration curve exhibits good linearity in the studied range of concentration (3–18 μg/mL).
Low values of relative standard deviation (<2%) were observed indicating that the proposed method is reproducible, accurate, and precise.
Conclusions: As per the existing guidelines of ICH (international council for harmonization of technical requirements for pharmaceuticals for human
use), various parameters of the proposed method were tested for validation and can be used method of choice for routine analysis in industrial quality
control laboratories, especially in developing countries.
A novel Ru/TiO2 hybrid nanocomposite catalyzed photoreduction of CO2 to metha...Pawan Kumar
A novel in situ synthesized Ru(bpy)3/TiO2 hybrid nanocomposite is developed for the photoreduction of
CO2 into methanol under visible light irradiation. The prepared composite was characterized by means of
SEM, TEM, XRD, DT–TGA, XPS, UV–Vis and FT-IR techniques. The photocatalytic activity of the synthesized
hybrid catalyst was tested for the photoreduction of CO2 under visible light using triethylamine
as a sacrificial donor. The methanol yield for the Ru(bpy)3/TiO2 hybrid nanocomposite was found to be
1876 μmol g−1 cat (MeOH 0.024 mol Einstein−1) that was much higher in comparison with the in situ synthesized
TiO2, 828 μmol g−1 cat (MeOH 0.010 mol Einstein−1) and the homogeneous Ru(bpy)3Cl2
complex, 385 μmol g−1 cat (MeOH 0.005 mol Einstein−1).
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Poster presentation delivered at the 2013 CASANZ conference by Katestone Senior air quality consultant Sarah Jane Donnelly. The poster presents a case study for the Tomago Aluminium Smelter to investigate the cause of exceedances of the 24-hour average air quality standard for sulfur dioxide.
Adsorption Characteristics and Behaviors of Natural Red Clay for Removal of B...ijtsrd
The present study deals with the analysis and adsorption of Basic Yellow 28 BY28 onto low-cost natural red clay NRC . Adsorbent characterized by XRD, SEM, TG DTA, BET and BJH. The effect of the contact time, the temperature, the initial concentration, the pH and the adsorbent mass and on adsorption process were investigated using by batch adsorption technique and then the adsorption isotherm, kinetics, thermodynamics and equilibrium studies were performed. The pH effect on the removal of BY28 efficiency was not important. It was found that the isotherm model best suited to the equilibrium data obtained from the adsorption of BY28 on NRC was the pseudo-second order. It was found that the kinetic model best suited to the data obtained from the adsorption of BY28 on NRC was the Langmuir model. The maximum monolayer adsorption capacity was 370 mg. g-1. In the thermodynamic studies, it can be said that the adsorption of BY28 onto NRC takes place spontaneously, physically and endothermic ally. Finally, the use of NRC shows a greater potential for the removal of cationic dyes, as no costly equipment is required. Omer Lacin | Ali Haghighatnia | Fatih Demir | Fatih Sevim "Adsorption Characteristics and Behaviors of Natural Red Clay for Removal of BY28 from Aqueous Solutions" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-2 , February 2019, URL: https://www.ijtsrd.com/papers/ijtsrd21544.pdf
Paper URL: https://www.ijtsrd.com/engineering/engineering-chemistry/21544/adsorption-characteristics-and-behaviors-of-natural-red-clay-for-removal-of-by28-from-aqueous-solutions/omer-lacin
Vapor growth of binary and ternary phosphorus-based semiconductors into TiO2 ...Pawan Kumar
We report successful synthesis of low band gap inorganic polyphosphide and TiO2 heterostructures with the aid of short-way transport reactions. Binary and ternary polyphosphides (NaP7, SnIP, and (CuI)3P12) were successfully reacted and deposited into electrochemically fabricated TiO2 nanotubes. Employing vapor phase reaction deposition, the cavities of 100 μm long TiO2 nanotubes were infiltrated; approximately 50% of the nanotube arrays were estimated to be infiltrated in the case of NaP7. Intensive characterization of the hybrid materials with techniques including SEM, FIB, HR-TEM, Raman spectroscopy, XRD, and XPS proved the successful vapor phase deposition and synthesis of the substances on and inside the nanotubes. The polyphosphide@TiO2 hybrids exhibited superior water splitting performance compared to pristine materials and were found to be more active at higher wavelengths. SnIP@TiO2 emerged to be the most active among the polyphosphide@TiO2 materials. The improved photocatalytic performance might be due to Fermi level re-alignment and a lower charge transfer resistance which facilitated better charge separation from inorganic phosphides to TiO2.
All about Radiations, Different energy particles- starting from Basics to New methods of analysis also includes DIfferent applications related to it.
Medha Thakur
(M.Sc Chemistry)
Thermo luminescence Dating of Quartz Sediments Extracted from the Terraces of...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Objective: The objective of the study was to develop a simple, validated, and affordable visible spectrophotometric method for determination of
piperacillin (PIP) present in bulk and powder for injection formulation.
Methods: In the present method, cobalt thiocyanate (CTC) was used as a chromogenic reagent where it forms 2:1 ion pair complex at pH 2 with PIP
which is having secondary and tertiary amine groups.
Results: The formed bluish-green colored ion pair between PIP and CTC is quantitatively extractable into nitrobenzene with an absorption maximum of
665 nm. Regression analysis (r=0.9996) shows that the plotted calibration curve exhibits good linearity in the studied range of concentration (3–18 μg/mL).
Low values of relative standard deviation (<2%) were observed indicating that the proposed method is reproducible, accurate, and precise.
Conclusions: As per the existing guidelines of ICH (international council for harmonization of technical requirements for pharmaceuticals for human
use), various parameters of the proposed method were tested for validation and can be used method of choice for routine analysis in industrial quality
control laboratories, especially in developing countries.
A novel Ru/TiO2 hybrid nanocomposite catalyzed photoreduction of CO2 to metha...Pawan Kumar
A novel in situ synthesized Ru(bpy)3/TiO2 hybrid nanocomposite is developed for the photoreduction of
CO2 into methanol under visible light irradiation. The prepared composite was characterized by means of
SEM, TEM, XRD, DT–TGA, XPS, UV–Vis and FT-IR techniques. The photocatalytic activity of the synthesized
hybrid catalyst was tested for the photoreduction of CO2 under visible light using triethylamine
as a sacrificial donor. The methanol yield for the Ru(bpy)3/TiO2 hybrid nanocomposite was found to be
1876 μmol g−1 cat (MeOH 0.024 mol Einstein−1) that was much higher in comparison with the in situ synthesized
TiO2, 828 μmol g−1 cat (MeOH 0.010 mol Einstein−1) and the homogeneous Ru(bpy)3Cl2
complex, 385 μmol g−1 cat (MeOH 0.005 mol Einstein−1).
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Poster presentation delivered at the 2013 CASANZ conference by Katestone Senior air quality consultant Sarah Jane Donnelly. The poster presents a case study for the Tomago Aluminium Smelter to investigate the cause of exceedances of the 24-hour average air quality standard for sulfur dioxide.
Adsorption Characteristics and Behaviors of Natural Red Clay for Removal of B...ijtsrd
The present study deals with the analysis and adsorption of Basic Yellow 28 BY28 onto low-cost natural red clay NRC . Adsorbent characterized by XRD, SEM, TG DTA, BET and BJH. The effect of the contact time, the temperature, the initial concentration, the pH and the adsorbent mass and on adsorption process were investigated using by batch adsorption technique and then the adsorption isotherm, kinetics, thermodynamics and equilibrium studies were performed. The pH effect on the removal of BY28 efficiency was not important. It was found that the isotherm model best suited to the equilibrium data obtained from the adsorption of BY28 on NRC was the pseudo-second order. It was found that the kinetic model best suited to the data obtained from the adsorption of BY28 on NRC was the Langmuir model. The maximum monolayer adsorption capacity was 370 mg. g-1. In the thermodynamic studies, it can be said that the adsorption of BY28 onto NRC takes place spontaneously, physically and endothermic ally. Finally, the use of NRC shows a greater potential for the removal of cationic dyes, as no costly equipment is required. Omer Lacin | Ali Haghighatnia | Fatih Demir | Fatih Sevim "Adsorption Characteristics and Behaviors of Natural Red Clay for Removal of BY28 from Aqueous Solutions" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-2 , February 2019, URL: https://www.ijtsrd.com/papers/ijtsrd21544.pdf
Paper URL: https://www.ijtsrd.com/engineering/engineering-chemistry/21544/adsorption-characteristics-and-behaviors-of-natural-red-clay-for-removal-of-by28-from-aqueous-solutions/omer-lacin
Vapor growth of binary and ternary phosphorus-based semiconductors into TiO2 ...Pawan Kumar
We report successful synthesis of low band gap inorganic polyphosphide and TiO2 heterostructures with the aid of short-way transport reactions. Binary and ternary polyphosphides (NaP7, SnIP, and (CuI)3P12) were successfully reacted and deposited into electrochemically fabricated TiO2 nanotubes. Employing vapor phase reaction deposition, the cavities of 100 μm long TiO2 nanotubes were infiltrated; approximately 50% of the nanotube arrays were estimated to be infiltrated in the case of NaP7. Intensive characterization of the hybrid materials with techniques including SEM, FIB, HR-TEM, Raman spectroscopy, XRD, and XPS proved the successful vapor phase deposition and synthesis of the substances on and inside the nanotubes. The polyphosphide@TiO2 hybrids exhibited superior water splitting performance compared to pristine materials and were found to be more active at higher wavelengths. SnIP@TiO2 emerged to be the most active among the polyphosphide@TiO2 materials. The improved photocatalytic performance might be due to Fermi level re-alignment and a lower charge transfer resistance which facilitated better charge separation from inorganic phosphides to TiO2.
All about Radiations, Different energy particles- starting from Basics to New methods of analysis also includes DIfferent applications related to it.
Medha Thakur
(M.Sc Chemistry)
Thermo luminescence Dating of Quartz Sediments Extracted from the Terraces of...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Carlos Afonso, Université de Rouen, Laboratoire COBRA, Plateau technique C2iorga
In this presentation, Carlos Afonso describes the analysis of polymers and petroleum by ion mobility mass spectrometry and utilises novel sample introduction techniques such as the Atmospheric Solids Analysis Probe (ASAP).
Presentation given by Dr Tina Düren from University of Edinburgh on "Molecular simulation of carbon capture in MOFs: challenges and pitfalls" in the Capture Technical Session on Solid Adsorption at the UKCCSRC Biannual Meeting - CCS in the Bigger Picture - held in Cambridge on 2-3 April 2014
Measuring and monitoring soil carbon stocks from point to continental scale i...ExternalEvents
This presentation was presented during the 2 Parallel session on Theme 1, Monitoring, mapping, measuring, reporting and verification (MRV) of SOC, of the Global Symposium on Soil Organic Carbon that took place in Rome 21-23 March 2017. The presentation was made by Mr. Jeff Baldock, from CSIRO - Australia, in FAO Hq, Rome
PhD research presentation at the workshop of the Climate Food and Farming Network, Dec. 2-4 at Aarhus University, Foulum. The Climate Food and Farming Network is an initiative of Copenhagen U., Aarhus U., and the CGIAR Research Program on Climate Change, Agriculture and Food Security.
1. 25 March 2015
Robert Healy
Chemical and optical properties of
black carbon particles in Toronto
(CHEMBC)
2. 2
Background- Black carbon
- “Black carbon” particles strongly absorb visible light across all wavelengths
- Sources include incomplete combustion of fossil fuels (vehicles, industry) and biomass
(domestic burning, forest fires)
- Exert a positive direct radiative forcing (warming effect on climate)
- High uncertainty associated with climate impacts
http://www.catf.us/climate/http://www.geog.ucsb.edu/
5. 5
- Black carbon (BC) particles are small, typically composed of multiple spherules,
each with a diameter of about 20 nm
100 nm
Black carbon absorption
7. 7
- BC particles accumulate organic and inorganic secondary coatings during
atmospheric transport
organic/inorganic coating
300 nm
Black carbon absorption
8. 8
- Coated black carbon can still absorb incoming radiation directly
Black carbon absorption
9. 9
- Enhanced absorption of solar radiation has been proposed to occur through a
“lensing effect” (refraction) for coated BC
- This enhancement effect has been demonstrated in laboratory studies
- But estimates of the enhancement for ambient BC vary greatly (6-50%), and thus
measurements in different environments are needed
BC absorption enhancement (Eabs)
Cappa et al., Science 2012
10. 10
Motivation
- Does BC coating composition and thickness affect absorption efficiency?
- If so, what is the impact in Toronto?
???
13. 13
Campaign and instrumentation
Soot particle aerosol mass
spectrometer
(SP-AMS)
Proton transfer
reaction mass
spectrometer
(PTR-MS)
Photoacoustic soot spectrometer (PASS)
Thermodenuder
Aerosol time of flight
mass spectrometer
(ATOFMS)
14. 14
Campaign and instrumentation
Instrument Function
Photoacoustic soot spectrometer
(PASS-3)
Measures aerosol absorption/scattering at
405 nm and 781 nm
Soot particle aerosol mass spectrometer
(SP-AMS)
Measures BC and coating material
concentrations quantitatively
Aerosol time-of-flight mass spectrometer
(ATOFMS)
Measures single particle composition and
mixing state qualitatively
15. 15
250 °C
Remove coatings using
thermal denuder
Experimental configuration
- Measure absorption for coated and uncoated (denuded) particles
- Is there a difference?
Measure absorption (babs)
using PASS
Measure absorption (babs)
again using PASS
21. 21
Absorption Ångström exponent (AAE)
Absorption(babs)
800700600500400
Wavelength (nm)
Lensing-related absorption
BC absorption
AAE = 1
AAE = 1
- Impact of optical lensing absorption enhancement on AAE
- If lensing is occurring, we should observe an enhancement at 405 nm AND 781 nm
22. 22
Absorption Ångström exponent (AAE)
Absorption(babs)
800700600500400
Wavelength (nm)
Brown carbon absorption
BC absorption
AAE = 1
AAE = 2
- AAE of “brown carbon”, associated with biomass burning, is typically ~2 or greater
- Could explain the absorption enhancement being observed only at 405 nm
29. 29
Mie theory predictions of lensing Eabs at 781 nm
1.1 2.0 1.1 1.9 1.2 2.0
By comparison we observe 1.0 for our campaign
30. 30
Conclusions
- Optical lensing is not relevant for BC in Toronto, even when the site is influenced by
BC particles with large coatings
- Direct absorption by brown carbon is relevant when the site is influenced by wildfires,
however, and is responsible for over 50% of direct absorption at 405 nm at times
- If radiative forcing is estimated using composition data and Mie theory, regional
warming is substantially overpredicted
- Care must be taken when accounting for BC internal mixing in climate models, and
further studies of absorption enhancement in other environments are necessary
34. 34
Single particle sampling- online:
ATOFMS
- Single particle information retained
- Enables source identification and investigation of chemical processing
- Data typically qualitative only
Data output:
Single particle
mixing state
(qualitative)
35. 35
Quantitative approach
- Derived ATOFMS mass spectral relative sensitivity factors (RSF) for OA, BC,
NH4, NO3 and SO4
- Calculated quantitative chemical composition estimates for each single particle
Healy et al. Atmos. Chem. Phys. 2013
RSF
quantitative
36. 36
Quantitative approach
- Chemical composition of each particle in the population can also be summed to
produce size-resolved bulk composition information
30
25
20
15
10
5
0
dM/dlogDp(µgm
-3
)
900
800
700
600
500
400
300
200
Aerodynamic diameter (nm)
NH4
NO3
SO4
OA
BC
quantitative
38. 38
Parameterisation of particle mixing state
• To what extent is each chemical species represented in a particle?
• Shannon entropy is used to determine this representation, similar to
applications in biodiversity and ecology
• For a single particle (i)…
𝐻𝑖 =
𝑎=1
𝐴
−𝑝𝑖
𝑎
ln 𝑝𝑖
𝑎
Mass fraction of species a (for example SO4) in particle i
Shannon entropy
Riemer & West, Atmos. Chem. Phys. 2013
39. 39
Single particle diversity (Di) examples
• Example 1: 2 species, equal proportions
Hi = (-0.5ln(0.5))+(-0.5ln(0.5)) = 0.69
The single particle diversity (Di), defined as e(Hi) = 2.0
OA BC
40. 40
Single particle diversity (Di) examples
• Example 2: 2 species, unequal proportions
Single particle diversity (Di) = 1.8
OA
BC
Typical fresh combustion particle
41. 41
Single particle diversity (Di) examples
• Example 4: 5 species, unequal proportions
Single particle diversity (Di) = 4.2
OA
BC
NH4
NO3
SO4
Typical aged particle
42. 42
The MEGAPOLI campaign Paris 2010
PARIS
SIRTA
LHVP
20km
GOLF
Livry
- ‘MEGAPOLI’ winter campaign site locations
ATOFMS
Sampling took place over 4 weeks in Jan/Feb 2010
43. 43
Paris single particle example 1
Relativepeakarea(arbitraryunits)
200180160140120100806040200
m/z
+
-
C
+
C3
+
C4
+
C2
-
C5
+
C3
-
C5
-
C2
+
Ca
+
C4
-
HSO4
-
SO4
OA
BC
Di = 2.0
Healy et al. Atmos. Chem. Phys. 2014
46. 46
Whole dataset: Paris
• We can average Di across all particles for every hour of the
measurement period
• This average value is termed Dα, and represents how well mixed
chemical species are at the single particle level only
• What about the bulk aerosol?
47. 47
Bulk aerosol diversity (Dγ)
• Bulk diversity is easier to calculate for each hour
• Shannon entropy calculated from the mass fractions of each species
present in the bulk aerosol
NO3
SO4
OA
BCNH4
Bulk aerosol diversity Dγ = 4.5
48. 48
Quantifying aerosol mixing state (χ) in Paris
• Relating Dα and Dγ gives the quantitative mixing state index (χ)
• Expressed as a percentage
• Average value for Paris χ = 59%
49. 49
Mixing state (χ) as a function of time
1.0
0.8
0.6
0.4
0.2
0.0
Bulkpopulation
massfraction26/1/201027/1/201028/1/201029/1/201030/1/201031/1/20101/2/20102/2/2010
3/2/20104/2/20105/2/2010
6/2/2010
7/2/20108/2/2010
9/2/2010
10/2/201011/2/2010
Date
70
60
50
40
4.0
3.5
3.0
2.5
2.0
D
4.5
4.0
3.5
3.0
D
C M C
D
D
NH4
NO3
SO4
OA
BC
1.0
0.8
0.6
0.4
0.2
0.0
Bulkpopulation
massfraction26/1/201027/1/201028/1/201029/1/201030/1/201031/1/20101/2/20102/2/2010
3/2/2010
4/2/20105/2/2010
6/2/2010
7/2/20108/2/2010
9/2/2010
10/2/201011/2/2010
Date
70
60
50
40
4.0
3.5
3.0
2.5
2.0
D
4.5
4.0
3.5
3.0
D
C M C
D
D
NH4
NO3
SO4
OA
BC
50. 50
Dependence of χ on air mass origin
26. Jan 2010 18:00 to 21:00
-5 0 5 10 15 20 25 30
42
44
46
48
50
52
54
56
[ns/kg]
0.005 0.01 0.02 0.04 0.08 0.16 0.32 0.64 1.28 2.56
Continental
1.0
0.8
0.6
0.4
0.2
0.0
Bulkpopulation
massfraction26/1/201027/1/201028/1/201029/1/201030/1/201031/1/20101/2/20102/2/2010
3/2/2010
4/2/20105/2/2010
6/2/2010
7/2/20108/2/2010
9/2/2010
10/2/201011/2/2010
Date
70
60
50
40
4.0
3.5
3.0
2.5
2.0
D
4.5
4.0
3.5
3.0
D
C M C
D
D
NH4
NO3
SO4
OA
BC
1.0
0.8
0.6
0.4
0.2
0.0
Bulkpopulation
massfraction26/1/201027/1/201028/1/201029/1/201030/1/201031/1/20101/2/20102/2/2010
3/2/2010
4/2/20105/2/2010
6/2/2010
7/2/20108/2/2010
9/2/2010
10/2/201011/2/2010
Date
70
60
50
40
4.0
3.5
3.0
2.5
2.0
D
4.5
4.0
3.5
3.0
D
C M C
D
D
NH4
NO3
SO4
OA
BC
51. 51
Dependence of χ on air mass origin
03. Feb 2010 18:00 to 21:00
-20 -15 -10 -5 0 5
40
45
50
55
[ns/kg]
0.005 0.01 0.02 0.04 0.08 0.16 0.32 0.64 1.28 2.56
26. Jan 2010 18:00 to 21:00
-5 0 5 10 15 20 25 30
42
44
46
48
50
52
54
56
[ns/kg]
0.005 0.01 0.02 0.04 0.08 0.16 0.32 0.64 1.28 2.56
Marine
1.0
0.8
0.6
0.4
0.2
0.0
Bulkpopulation
massfraction26/1/201027/1/201028/1/201029/1/201030/1/201031/1/20101/2/20102/2/2010
3/2/2010
4/2/20105/2/2010
6/2/2010
7/2/20108/2/2010
9/2/2010
10/2/201011/2/2010
Date
70
60
50
40
4.0
3.5
3.0
2.5
2.0
D
4.5
4.0
3.5
3.0
D
C M C
D
D
NH4
NO3
SO4
OA
BC
1.0
0.8
0.6
0.4
0.2
0.0
Bulkpopulation
massfraction26/1/201027/1/201028/1/201029/1/201030/1/201031/1/20101/2/20102/2/2010
3/2/2010
4/2/20105/2/2010
6/2/2010
7/2/20108/2/2010
9/2/2010
10/2/201011/2/2010
Date
70
60
50
40
4.0
3.5
3.0
2.5
2.0
D
4.5
4.0
3.5
3.0
D
C M C
D
D
NH4
NO3
SO4
OA
BC
53. 53
Conclusions Part 2
• ATOFMS data can be used to estimate single particle composition
• Calculating single particle diversity and bulk aerosol diversity enables an
assessment of aerosol mixing state (χ)
• Aerosol mixing state depends on local emissions, chemical processing and
regional transport
• Aerosol diversity measurements can be used to evaluate the error
introduced in climate models when internal mixing is assumed
54. 54
Thank you
Questions?
University College Cork
J.C. Wenger, J.R. Sodeau, I.P. O’Connor,
E. McGillicuddy, J. Arndt
University of Toronto
J.M. Wang, C.-H. Jeong, A.K.Y. Lee, M.D. Willis,
N. Hilker, J.P.D Abbatt, G.J. Evans
University of Illinois
N. Riemer, M. West
Norwegian Institute for Air Research
S. Eckhardt, A. Stohl
57. 57
Aerosol absorption and the Beer-Lambert Law
I = I0e-αlc
I = outgoing light
I0 = incident light
α = absorption cross section (m2 g-1) (α is often termed the “MAC” value)
l = path length (m)
c = concentration (g m-3)
babs is the product of α and c (m-1)
and is measured directly by the PASS
Scattering (and extinction) calculations are analogous to absorption
58. 58
Terminology
BC (black carbon, measured quantitatively by SP-AMS)
babs (absorption coefficient measured by PASS)
Eabs (absorption enhancement)
MAC (mass absorption cross-section)
NR-PMBC (non-refractory particulate matter on BC, measured by SP-AMS)
NR-PMBC/BC (coating-to-core mass ratio for BC-containing particles)
69. 69
Assumptions
• All particles are spherical with a density of 1.5 g cm-3 for aerodynamic
diameter to mobility diameter conversions prior to scaling
• All particles are composed exclusively of NH4, SO4, NO3, OA and BC
• ATOFMS ‘sees’ all particle types with equal efficiency at a given size
70. 70
Why do we need Dα and Dγ? Example 1
NO3NH4
OA BC
NO3NH4
NO3NH4
NO3NH4
NO3NH4
NO3NH4
OA BC
OA BC
OA BC
OA BC
OA BC
Dα = 2.0 Dγ = 4.0
NO3 OA
BCNH4
SINGLE PARTICLE BULK AEROSOL
71. 71
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4 NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
Dγ = 4.0Dα = 4.0
Why do we need Dα and Dγ? Example 2
SINGLE PARTICLE BULK AEROSOL
73. 73
Diurnal dependence of Dα Dγ and χ
5.0
4.5
4.0
3.5
3.0
D
3.23.13.02.92.82.72.62.5
D
20
15
10
5
0
Hourofday
OA BC
OA BC
OA BC OA BC
OA BC
OA BC
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
NO3 OA
BCNH4
75. 75
Relative sensitivity factors by species
3
4
5
6
1
2
3
4
5
6
10
2
3
4Relativesensitivityfactor(arbitraryunits)
SO4
OA
NH4
NO3
BC
Box-plot of hourly mass spectral relative sensitivity factors (n = 610). Median,
75th percentile and 90th percentile are denoted by the solid line, box and
whisker respectively.