Air Pollution Studies - Science topic

As for the critical point in maintaining conditions favorable for life on Earth, it is possible that it has already been exceeded. The idea that a larger community, or even all people on Earth, will come to a common conclusion and make politically effective decisions that something needs to be stopped and something needs to be started on a global scale is fundamentally wrong, because people are not capable of overcoming the currently existing political structures. The decisions you wrote about could only be made by people in power and in the event of a disaster that directly threatens them. But by then, of course, it will be much too late to avoid it. What is the deepest motivation of people in power is the desire to gain and maintain it, and not some common good serving all people in a given community, in a given country, or around the world. So there is no hope for the future for us, because decisions about arming and preparing for further wars have already been made and the current political structures are capable of doing so. And they are not suitable for actions, at least on a similar scale, to save the natural environment on Earth. I don't know what we should do in this situation. Protests and appeals to politicians do not work. The world is ruled by people like Putin or not much better.

ZJ

Okay! Will do

El método de INTERPOLACION de Krigin resulta más apropiado por su capacidad espacial.

"Health Risk" is usually measured as a concentration of a compound over time in a particular area. The toxicity levels of hazardous chemicals are catalogued by OSHA and the EPA. If you are looking for a dispersion model, the EPA used to have one that we used for Facility Risk Planning and Community organizations.

Thanks for the question. The answers also interest me

The negative sign loading means this parameter has an opposite effect from the other parameters of positive sign. Additionally, when the concentration of the parameters of positive sign rise, the concentration of the other parameter of negative sign will decrease.

For ambient air quality data, log normal distributions are commonly used for some of the reasons you are concerned with. In many cases, in my opinion, the mode may be a more conservative measure risk and exposure analyses. Unfortunately I do not have references to peer reviewed work comparing the errors of one or the parameter used.

Research indicates that nitrogen oxides and sulfur dioxide have an effect on increasing the risk of cancer.

The direct greenhouse gases are carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4). The indirect greenhouse gases are non-methane volatile organic compounds (NMVOCs), nitrogen oxides (NOx) comprised of nitrogen monoxide (NO) and nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO).

If you use PCA, you can run any analysis you want on the newly created PCA variables, including correlation with other variables.

If you use CCA, you need an environmental matrix.

Your answer lies in your data structure and what you hope to accomplish.

The ability of a plant to absorb pollutants is dependent on a number of factors (age of the plant, nature of pollutants,, concentration of pollutants in the microspace around the plant, soil and weather conditions) apart from the species' inherent potentials.

Therefore, a design to compare plants tolerance to pollution to pollution absorption may be somewhat difficult.

Here a paper of chemical composition and source apportionment of PM10 in a city at 2,650 m:

Both US EPA and the US Army (Dugway Proving Ground in Utah) have conducted extensive urban dispersion modelling studies with both real and modelled buildings. 

This is a vague question; air quality--and some accompanying meteorological data for selected pollutants in the US--data are available at epa.gov/outdoor-air-quality data.  This site have both "raw" data, formatted data, and data reports.  The raw data should be available on a site-specific basis, but I have not checked.  Generally there is a lag time of a year in putting the information on the web, but otherwise it can be obtained for many years on a site-specific basis. 

There are scores--probably thousands--of statistical and/or chemical/physical models used to estimate ambient air quality, depending upon the pollutant of interest, its "averaging time," its modeling domain, epoch, and receptors of interest.  See the above answers.

Dear Mr. Sarker,

It is a very interesting problem which can be approached in different ways. In my opinion to predict air quality from overall meteorological patterns, traffic count, traffic speed you should create a weight based equation which combine the previous parameters according to their degree of influence e.g. 50% for traffic count, 25% for meteorological patterns...etc. It would be better if the previous collected parameters are classified then using ordinal numbers each is given a weight and summed. Then according to the measured carbon monoxide, sulfur dioxide, and nitrogen dioxide we can fit a nonlinear equation for each pollutant level. You can also use supervised ANN to find a solution too using the parameters of the meteorological patterns, traffic count...etc and the measured pollutants.

It is better to try to find if there is strong correlation between these parameters and measured pollutants. If there is no correlation for specific parameter then I would remove it to increase confidence and accuracy of the final prediction function.

You can check my publication for predicting physiochemical parameters using measured and calculated parameters. But, in these publications I am using one parameter only.

Interesting ...

I had a read of your ACPD manuscript ( http://www.atmos-chem-phys-discuss.net/acp-2017-204/ ) and I have some comments that hopefully will help answer your question.

First, and as everyone here has said, do make sure that your PM heads are the right ones (i.e., that they were operating within their flow parameters).

Now, I was as intrigued as "Referee 1" about the fact that you report higher concentrations of fungal spores on PM1 than on PM2.5 filters while the PM1 fraction is contained within the PM2.5 fraction.

I have two comments about this issue. The first one on the nature of PM1 and PM2.5 and the second one on the uncertainties of the measurements.

First, PM1 and PM2.5. While it is true that, conceptually, PM1<PM2.5. That is true in practice only when you sample with one inlet. As you and anyone who has captured filter samples "in the wild", two PM1 filters sampled side by side will NEVER measure exactly the same concentration of particles, now if you have a cascade impactor then you can be sure that the what is on the PM1 stage is not on the PM2.5 stage but with parallel samples (as per your setup) you can't be 100% sure of that and you need to assess your uncertainty about the full PM1 and PM2.5 concentrations.

This leads me to the second point about uncertainties. I had a look at Table 1 in your article and I estimated the 95% confidence of the means that you report for "Fungal SSU rRNA gene copy number" for the PM2.5 and PM1 fractions:

Which to me says that those two means are not significantly different.

And now things make some sense in my head because the concentration of fungal spores as a fraction of the PM concentration is less than 0.1% which is a lot less than the variability you'd find between identical instruments sampling the same air. In my experience, 1% agreement between "side-by-side" instruments is an excellent result and you're well within that error margin.

Fungi will not "purify" air (it has no technical meaning), some can reportedly reduce levels if VOC's.  As you say there will be a tradeoff, but it reportedly can be minimal.

Hello, I think yes, because any continuous time series can be discretised and analyzed as a discrete time series. But you must look at the long of your time series because of you need to apply statistical tools among others tools. Also you should keep in ind if the time series is linear or nonlinear. For instance, Pm2.5 and PM10 concentrations are nonlinear and you should work with carefully!

I think the attached review articles may be helpful for your question.

Good luck

There are virtually hundreds of different dispersion models around. If you look at the top of the page, it says: "This annex documents simple models for first estimation or screening." And that's what it is.

For instance, Model C is applicable on roads with complete obstruction by buildings on both sides of the road. Model D does not consider any buildings. A real dispersion situation will be somewhere in between. And the dominant wind direction will not be in a 90° angle to the road and... The selection of a suitable model depends on the situation you want to analyse. And on the level of detail you want to (or have to) achieve.

Amir

A question starts with the reference for the statement

It is not enough to write "I read SOMEWHERE" you have to write where you read that

Bryophyte (moss) genome obviously is the most reliable. But you can identify mosses using a key that details things such as:

Is the gametophyte colony dark green or greyish-white in appearance?

Is the mature spore capsule upright or nodding?

When dry, do the leaves twist around the stem or simply fold inwards to the stem?

Does the leaf have a nerve or not ?

Are the cells in the lower leaf corners markedly different from the other leaf cells?

How large are the spores?

Lichens are not really plants – they are a combination of fungi and algae and are classified based on the fungus and fungal features. In order to identify lichen to species level, lichenologists use common household chemicals and some not-so-common chemicals to test the color reaction of the unique compounds found in the structure of the lichen, as well as using a lichen key to distinguish between species.

Should be Section 58.3 of the NAAQS document from the US-EPA. Some of the appendix info with siting specifications is available here: https://www.law.cornell.edu/cfr/text/40/part-58/appendix-E

The modelling of light-induced reaction is a very complex task. I agree with Kenneth:" I don't see how there could be any one effective length.."  I believe that "the effective path length" is an oversimpliification to describe a real system. The refs you provided are not from the top journals. "The effective path length" is not well defined and is not generally used in the literature. 

The 10 micrometer is not the actual size, but an eqivalent aerodynamic size. A PM10 particle may have a physical dimension exceeding 10 micrometers. Definition: The aerodynamic diameter of an irregular particle is defined as the diameter of the spherical particle with a density of 1000 kg/m3 and the same settling velocity as the irregular particle.

According to the current definition, PM2.5 particles are a part of PM10.

Try calculating Emission Factors in the category Fugitive Dust from paved or unpaved road. Check more info. From USA EPA at https://www3.epa.gov/ttnchie1/ap42/ch13/related/c13s02.html

Dear Michal

The Dr  Sébastien Vaesen's answer is completely perfect 

Enrichment Factor (EF) of any element X in aerosols can be calculated using the following formula:

EF of X = (X/Al)samples / (X/Al) in ucc

here, ucc stands for upper continental crust. For more details, you can read the attached paper.

It does depend which issues of concern you have 

Ex http://www.mfe.govt.nz/publications/air/good-practice-guide-air-quality-monitoring-and-data-management-2009/2-why-monitor-%E2%80%93

WHO gives 10 aims of AQ monitoring including evaluation of correspondence to limit values, estimation of sources of pollution, evaluation of accuracy of modelling, evaluation of risks to human health of plants, estimate the trends, model the future trends etc

So, 1st determine which issues are important in your area-city. Then you can choose does analyses of your data help to solve/answer issues concerned.

Thus, the answer depends on situation in your site-area.

There are different legislative targets set for the next years, e.g. 95 g/km CO2 fleet emission in the EU in 2021. Some links, which might be of interest for you:

Kind regards,

Mario

It might be worthwhile to have a look at

http://charmeck.org/mecklenburg/county/LUESA/AirQuality/ PermittingRegulations/Pages/emissioncalcspsheet.aspx

It is pretty nice speadsheets where one of them i actually specially designed for emissions from crematoria.

good luck

For free on the web

Chemical Reaction Engineering

Third Edition

Octave Levenspiel

Hans Puxbaum is right, the relation with health hazards is weak, at least effects by inhalation. Although some indirect effects can be expected, for instance by uptake of deposited metals in vegetables, or by ingestion of polluted soil by children. But than again, this effect is uncertain.

If you can read German (perhaps with a bit of help of Google translate?), some more information is available at the sites of LANUV, the State Agency for Nature, Environment and Consumer Protection of North Rhine-Westphalia in Germany. Here are some links (Staubniederschlag is dust depostion):

http://www.lanuv.nrw.de/umwelt/luft/immissionen/staubniederschlag/ with background information, a short description of the Bergerhoff method, German norms for 5 metals and buttons to Messnetz( measurement network):

with indications of possible applications of the method like Hans Puxbaum meant,

and Messergebnisse (Measurement results):

with annual and trend publications on dust deposition and its components like Pb, Cd, As, Ni, Tl, Hg, and dioxins, furanes and PCB's.

Hope this helps!

Greetings,

Marcel Severijnen

Something like this one?

One option is to collect data in rural areas and compare .///chockalingam.civil@bharathuniv.ac.in

There has been a study made for the Boston Central Artery Project in the 1990s. They used a conveyer belt with half-globes to simulate vehicle movement in the wind tunnel. Number of globes and speed of the conveyer were varied in order to model different traffic situations. I don't have access to the report, but maybe you'll find something about the Boston project.

Carbon monoxide is not known as a direct contributor to climate change, however, it does play a role in this area, since its presence affects concentrations of other greenhouse gases including methane, tropospheric ozone and carbon dioxide (http://esseacourses.strategies.org/module.php?module_id=170).

With respect to your comments particularly about sulfate, another important source is sea salt, in which the concentration of this ion is usually around 10%, according to the SPECIATE database (Profile Number: 4310110). It is also well known that this ion is already present in seawater, due to the oxidation of Dimethyl Sulfide (DMS) emitted by phytoplankton, so it is definitely emitted as a primary aerosol, in this case.

Okay. There are a number of ways to do in vivo PM studies. I realize that there are few studies of very small (i.e. "ultrafines"), but new techniques are being developed. Check out Buckley, et al. (2016): http://www.tandfonline.com/doi/abs/10.1080/02786826.2015.1124987. There have been numerous pharmacological studies (e.g. drug delivery to the lung) that can help. For example, you might be able to apply alveolar deposition models (see: Khajeh-Hosseini-Dalasm and Longest (2016): http://www.sciencedirect.com/science/article/pii/S0021850214001487.

Dear Saifeldin,

The following publications may be helpful:

Rafik

Dear Researcher

please check this if it is helpful for you.

Hi Sarika,

I dont think so. I analysed monocarboxylic acids (C8 - C20) by GC-MS 5 years ago. I derivatized them into methyl esters by BF3/methanol and the peak area was different for different acids. The peak area of C16 was the biggest. However I dont have experiences with HPLC.

Rastislav.... PM10 means particles less than 10 micrometers. PM is Particulate Matter.

Hi Qiang Chen, would you please explain more about grey model

You can do benzene and CH4 and many other species by GC-FID if you use whole air sampling in canisters along with pre-concentration as described here:

Colman, J. J., A. L. Swanson, S. Meinardi, B. C. Sive, D. R. Blake, and F. S. Rowland, Description of the analysis of a wide range of volatile organic compounds in whole air samples collected during PEM-Tropics A and B, Anal. Chem., 73, 3723– 3731, 2001.

One could do that. There is sufficient difference in thermal conductivity between nitrogen and carbon dioxide to get a usable signal. However if the student is looking at normal carbon dioxide concentrations in ambient air (~400 ppm or so), the change in conductivity will be minimal. The thermal conductivity values could also be calculated based on the concentrations and standard values. The only case where the change would be substantial would be in the case of flue gas or combustion exhaust.

The attached US EPA publication "Quality Assurance Guidance Document 2.12: Monitoring PM2.5 in Ambient Air Using Designated Reference or Class I Equivalent Methods" may provide you with useful information about measuring fine particulates in ambient air.

Dear Anand,

Please read the following text:

Emission Examples: Stack Gas Concentrations

Example 1 - Converting CAC Releases from ppm (volume) to tonnes

If you have had your stack tested for NOx (expressed as NO2), Carbon Monoxide (CO), or Sulphur Dioxide (SO2) you will notice that the results from the laboratory are usually in the units of parts per million volume or ppm (volume). Before you can use these number to estimate your releases of these substances for the NPRI you need to Convert from ppm (volume) to a mass release in tonnes.

This example will walk you through the process of converting from ppm (volume) to an annual mass release in tonnes for NOx. This same method can be used for CO and SO2.

1. The first step is to calculate the stack's volumetric gas flow rate ( ) using the formula below:

(m3/min) = (gas velocity, m/s) * [π * (internal stack diameter, m)2 /4] * 60 s/min

where π = 3.1416

2. Then you need to correct the stack gas flow rate for the moisture content and standard conditions using the formula below:

Example: If the stack gas volumetric flow is 1330 m3/min at 80°C and 1 atm pressure with a moisture content of 10%, the dry volumetric stack flow rate is:

= 925.84 m3/min

3. The next step is to Convert from ppm (volume) to mass emission rate (kg/h) as follows:

Example: NOx is emitted from a stack that is 2.1 ppm by volume. The dry volumetric stack flow rate is 925.84 m3/min. Density of air at standard conditions is 1.29 kg/m3

= 0.239 kg/h

4. Use the mass emission rate to calculate the yearly NOx release.

= 2093.64 kg

= 2.09 tonnes NOx released for the year

Molecular Weights (MW) for Air and CAC Substances

CAC Substance

Molecular Weight (grams/mole)

Air

28.97

NOx (expressed as NO2)

46.00

Carbon Monoxide (CO)

28.00

Sulphur Dioxide (SO2)

64.06

 

Example 2 - Converting CAC Releases from ppm (mass) to tonnes

If you have had your stack tested for total particulate matter (TPM), PM10 or PM2.5 you will notice that the results from the laboratory are usually in the units of parts per million mass or ppm (mass). Before you can use these number to estimate your releases of these substances for the NPRI you need to convert from ppm (mass) to a mass release in tonnes.

This example will walk you through the process of converting from ppm (mass) to an annual mass release in tonnes for TPM. This same method can be used for PM10 and PM2.5 as well.

The first step is to convert from ppm (mass) to the mass emission rate as follows:Convert ppm to grams / tonne

Use the stack mass flow rate (kg/min) to Convert to mass emission rate.

Example: The TPM emission rate from the stack is 250 ppm (mass). The dry mass flow rate is 10.54 kg/min. The stack is operational 24 hours a day, 365 days a year.

(i.e.525 600 minute per year).

a) Convert from ppm to g/tonne by using the conversion of:

b) Using stack dry mass flow rate, calculate the mass emission rate:

2. Then use the mass emission rate to calculate the yearly TPM release.

The TPM release for this particular stack is 1.384 tonnes.

Example 3 - Converting CAC Releases from mass per volume to tonnes

If you have had your stack tested for volatile organic compounds (VOCs) you will notice that the results from the laboratory are usually in the units of mass per volume. Typically the result of the VOC stack testing is expressed in the units of m g/m3. Before you can use these numbers to estimate the release of these substances for the NPRI you need to Convert from the mass per volume values to an annual mass release in tonnes.

This example will walk you through the process of converting from a mass per volume value to an annual mass release in tonnes for VOCs.

1. The first step is to calculate the stack's volumetric gas flow rate (V) using the formula below:

V(m3/min) = (gas velocity, m/s) * [π * (internal stack diameter, m)2 /4] * 60 s/min

where π = 3.1416

2. Then you need to correct the stack gas flow rate for the moisture content and standard conditions using the formula below:

Example: If the stack gas volumetric flow is 1330 m3/min at 80°C and 1 atm pressure with a moisture content of 10%, the dry volumetric stack flow rate is:

= 925.84 m3/min

3. The next step is to use the stack flow rate (m3/min) to Convert to a mass emission rate as follows:

Example: VOCs are emitted from a stack that at a rate of 60 m g/m3. The dry volumetric stack flow rate is 925.84 m3/min.

Mass Emission Rate = 925.84 m3/min * 60 m g /m3 * 60 minute / hour

= 3 333 024 m g/hour

4. Use the mass emission rate to calculate the yearly VOCs release.

= 0.029 tonnes VOC

ASIDE:

The following two examples use the duration of the stack test to calculate an emission factor for the process. To simplify the calculation a test duration of one hour was used. If the duration of your stack testing was different you will first need to Convert it to a one hour basis before following the methods outlined in Examples 4 and 5.

Example: Stack duration is 2 hours and a TPM release value of 316.2 g during the test period.

Example: Stack testing was based on a total volume sampled instead of time. A total of 107 000 m3 of emissions needed to be tested. The dry volumetric stack flow rate was 1197 m3 per minute. The total release of VOCs during the testing period was 6.42g.

Example 4 - Calculating CAC Releases from Source Testing and Fuel Consumption Data

Many facilities participating in a stack testing program will have information on the fuel feed rate during the test period and total annual fuel consumption. This data can be used to more accurately estimate CAC releases taking into account the process variations and production rates. For example, you may choose to use this method if the equipment is only operation for part of the year or the fuel feed rate fluctuates based on the facility's production rate.

To illustrate this method the data in Example 2 was assigned to a boiler burning bituminous coal.

From Example 2:

1. The first step is to convert from ppm (mass) to the mass emission rate as follows:

Convert ppm to grams / tonne

Use the stack mass flow rate (kg/min) to Convert to mass emission rate.

Example: The TPM emission rate from the stack is 250 ppm (mass). The dry mass flow rate is 10.54 kg/min. The stack is operational 24 hours a day, 365 days a year.

(i.e.525 600 minute per year).

a) Convert from ppm to g/tonne by using the conversion of:

b) Using stack dry mass flow rate, calculate the mass emission rate:

converting to grams per hour:

2. Use the mass emission rate and the boiler fuel feed rate to Create CAC production rate to fuel consumption to Create an emission factor.

a) Use the general formula below to Create the emission factor:

Example: The TPM emissions being released from the stack are the result of combustion in a bituminous coal fired boiler. The stack testing results were based on a one hour test period. The fuel feed rate of the boiler during the test was 25 kg bituminous coal per hour.

3. Use the emission factor calculated above along with the boiler's specific total annual consumption of bituminous coal.

Example: The boiler in question burned 218.85 tonnes of bituminous coal in the reporting year. The calculated emission factor for TPM for this boiler was 6.324 kg per tonne bituminous coal burned.

= 1384 kg TPM released

= 1.384 tonnes TPM released

The TPM release for this particular stack is 1.384 tonnes.

Example 5 - Calculating CAC Releases from Source Testing and Total Production Data

Another method that can be used to estimate your CAC releases is to correlate your stack testing data with the facility's production data. Most facilities participating in a stack testing program will have information on the production rate during the test period and total annual production. This data can be used to more accurately estimate CAC releases taking into account the process variations and production rates. For example, you may choose to use this method if the process line is only operation for part of the year or the production rate fluctuates with demand for the product.

To illustrate this method the data in Example 3 was assigned to the fluidized bed prilling process used in urea production.

From Example 3:

1. The first step is to calculate the stack's volumetric gas flow rate (V) using the formula below:

V(m3/min) = (gas velocity, m/s) * [π * (internal stack diameter, m)2 /4] * 60 s/min

where π = 3.1416

2. Then you need to correct the stack gas flow rate for the moisture content and standard conditions using the formula below:

Example: If the stack gas volumetric flow is 1330 m3/min at 80°C and 1 atm pressure with a moisture content of 10%, the dry volumetric stack flow rate is:

= 925.84 m3/min

3. The next step is to use the stack flow rate (m3/min) to Convert to a mass emission rate as follows:

Example: VOCs are emitted from a stack that at a rate of 60 m g/m3. The dry volumetric stack flow rate is 925.84 m3/min.

Mass Emission Rate = 925.84 m3/min * 60 m g /m3 * 60 minute / hour

= 3 333 024 m g/hour

= 3.33 g/hour

Use the mass emission rate and the facility's production rate to Create CAC release to total production emission factor.

a) Use the general formula below to Create the emission factor:

NOTE: The facility's production rate can be in tonnes product produced, number of unit produced or any other applicable measure of production. Likewise, the CAC substance release could be in any units of mass. This example will use tonnes product produced and grams of substance released to illustrate the process.

Example: The VOC emissions being released from the stack are the result of the fluidized bed prilling processes used in urea production. The stack testing results were based on a one hour test period. The production rate of the facility during the test was 23 tonnes of urea per hour.

3. Use the emission factor calculated above along with the facility's total annual production of urea.

Example: The facility in question produces a total of 203 210 tonnes of urea in the reporting year. The emission factor calculated in, part 2 above, for VOCs from the fluidized bed prilling process, was 0.145g per tonne urea produced.

= 29 465.45g VOC released

= 0.029 tonnes VOC released

The VOC release for this particular stack is 0.029 tonnes.

 For better view, please use the following link:

For other references, please use the following links:

Hoping this will be helpful,

Rafik

Reduce emission of noxious gases in the environment and increase tree cover. 

University of Engineering and Technology (UTEC), Peru  has developed air-purifying billboard and installed near a construction zone in Lima, a city that's famous for having the worst air quality in all of South America. The billboard works by combining polluted air with water, using basic thermodynamic principles to actively dissolve the pollutants (such as bacteria, dust and germs) in water to release fresh air. It is claimed that the billboard filtered around 500,000 cubic meters of air within one week. Pl refer following threads for various devices claiming to purify air in various ways;-

http://www.gizmag.com/utecs-air-purifying-billboard-installed-at-lima/31931/].

Surprisingly enough, this SO2 plume has originated from the Etna Volcano, in Italy. The eruption on December 3rd was quite large and the SO2 plume rose as high as 7 or 8km while being constantly transported eastwards. There is no associated ash plume. Below you find an answer from Nicolas Theys, BIRA, Belgium.

------------------

This SO2 plume is coming from Etna eruption on 3rd December : http://sacs.aeronomie.be/nrt/IasiOfl/2015/12.orb_V3/03/iasiB_dbt20151203dc_207_lr.gif

You can follow the transport of the plume on SACS day by day until it reaches China.

The eruption was one the most vigorous eruption of Etna since the last 2 decades and the SO2 plume was emitted quite high (7-8 km) in the atmosphere where it was then transported Eastward as it is often the case for Etna plumes.

Aerosols play an important role in the global climate, the radiative forcing of climate, and the Earth’s radiative balance.  They act by modifying the local and planetary albed and by absorbing the upward terrestrial thermal radiation. Aerosols influence the radiation balance through two key processes: directly, by scattering and absorbing solar radiation, and indirectly, by acting as cloud condensation nuclei and thus dramatically affecting the optical properties of clouds.

see attached file as well to more detail about it.

Regards

I think we also should consider respirable particulates. The smallest fractions (PM2.5, PM1 and soot). They have very bad influence to human health, and controlling is very hard (e.g. resuspension from traffic).

Moreover, particulates are carriers for another pollutants, heavy metals ia.

Good morning

Thank you Silas Derenzo sir. 

sorry, I think the document with copper smelting is:

Remember you are talking about units of concentration. Hence, you are dealing with mass of PM per unit volume of ambient air. So, lets say that a substantial portion of your TSPM is made up of particles of sizes 10 microns and smaller. Then, you will expect that there will actually be a large concentration of particulate mater of size 10 microns and less when you look individually at this one fraction of PM in the ambient air. So yes, it is possible.

Yes

Hi, do you have downstream applications - or do you just need the counts? In case yiu do not need the slids afterwards: I would stain the spores to enhance the contrast (Lacto-glycerine cotton blue), take microscopic photos or a simple scan (depending on objects size) and than try Fiji (ImageJ), using thresholding and automatic counting (depending on quantity). It is useless, if the spores lie too close to each other and do not seperate in the picture. In some cases you need expensive software or a lot of patience -

Dear Jaime,

An adult man needs about 700 grams of oxygen per day (255 kg/year), corresponding to what provide a dozen trees in one year (from 15 to 30 kg per tree). Urban tree therefore produces a very small share of the large amounts of oxygen consumed in large cities, but the native oxygen produced by the leaves could play an important health role for the trees themselves, and their proximity, notably in the canopy.

With my best regards

Prof. Bachir ACHOUR

Use the BC measurement at 880 nm to determine Black Carbon (BC) mass, the light absorbing organics usually do not absorb significantly there. Regression plots between BC from biomass burning and levoglucosan should provide the information on the robustness of your two-component Aethalometer model (biomass, fossil fuel). The intersect (BC at zero levoglucosan concentration) is an indicator of the levoglucosan stability and the accuracy of the  fossil AAE.

Hi Sabash,

i have no experience in this field .

best wishes,

Mark

I am not sure it there is any publication yet that reliably tells the particle size distribution of e-cigarettes and I doubt that there is any publication that based on the particle size distribution gives a reasonable health risk analyse:

1) e-cigarette vapor is completely volatile (by measuring the psd high dilution is required in order to prevent coagulation artefacts)

2) deposition in the human respiratory tract is based on particle size; however, e-cigarettes have a high potential of higroscopic growth but may also completely evaporate depending on their concentration. Equilibrium (in terms of phase transition) models can not be applied here, but most lung deposition models that consider phase transition are equilibrium models

I conclude: tricky topic

Dear Naveen,

Please go through the attached research article, may be helpful to you.

Dear Vitalii,

A very good source of public information on atmospheric emissions is the EMEP CEIP webpage (which includes Ukraine territory)

For meteorological data you can check the following webpage, which allows downloading the METAR data from the different meteorological networks all over the world

Regarding air quality data, I am only aware of the EEA air quality database, which you already posted in your comment. 

Hope the answer is hepful

Marc

Yes Francesco,

I received it. Thank you very much!

Felicita

Khotimah, 

Sure, what is the domain size, and where is the target area, you are looking for?

I think the easy to do this is using NOAA online dispersion model,

I suggest you to start from meteorological data of GDAS. However, if you are looking TSPs, deposition rate will vary with particle sizes. It will just give you a rough number of spatial variation of TSP near a certain source.

the only study I could find that measured Ventilation during walking (study with only 1 subject!) gives the following values: walking at 3 mph: 1.3 m3/h and walking at 5 mph: 1.6 m3/h.

Seems that only a very small number of studies measured ventilation in a direct way while walking, but that the results are comparable.

Bas de Geus

 I agree with the others, first it must be very clear the gas specie: molecular nitrogen? or a isotopomer of it? or other nitrogen compounds like N2O, or NOx? or do you want some of the nitrogen compounds? which ones? and where you want to collect the nitrogen in air? or is soil? if in air, you need a evacuated gas cylinder, use a GC-TCD with columns that separates permanent gases and  a GC gas inlet that take a few mbar (below the atmospheric pressure). Contrary to NOx, N2 and N2O are very stable with low humidity and oxygen in the sampling cylinder. In the National Metrology Institutes the N2 in measurement standards is normally a balance gas, so we do not measure it for calibration standards, like Certified Reference Materials (CRM), normally we measure in the N2 only the critical impurities for the application of the CRM. But you can measure N2 by GC-TCD!

The cause of PLE is not yet understood. It is thought to be due to a type IV delayed-type hypersensitivity to an allergen produced in the body following sunlight exposure. It can be provoked by UVA or UVB rays. Some progression to autoimmune disease has been observed. Pathogenic strains of H. pylori have been shown to

activate the epidermal growth factor receptor (EGFR), a membrane protein with a tyrosine kinase domain. Activation of the EGFR by H. pylori is associated with altered

signal transduction and gene expression in host epithelial cells that may contribute to pathogenesis.

Bashir A. H. H.1,2*, Yousif S. M.2 and Mahmoud M. O. A.2. Clinicoepidemiological study in Sudanese patients: Prevalence and effect of eradicative triple therapy on

extra digestive Helicobacter pylori skin manifestations, EdHpSm. Clinical Reviews and Opinions Vol. 3(2), pp. 14-19, February 2011.

Available online http://www.academicjournals.org/cro

ISSN 2141-2553 ©2011 Academic Journals

Hi,

I came across a few articles, searching for sources of a small but interesting PM event in Flanders, Belgium in July last year: "Detecting source of unexpected peak of PM10 over Flanders (Belgium): a walk through public available information". See my article on researchgate and look for references 20, 21, 22, 23, 24 and 25. You may find different correlations of course, depending on differences in the aerosols, and within the uncertainties of the methods. http://tinyurl.com/pnxlyks

Thank you for your answers. 

If you check Figure 2 in our paper, Fine particle air pollution and secondhand smoke exposures and risks inside 66 US casinos James L. Repace a,b,n, Ruo-Ting Jiang c, Viviana Acevedo-Bolton c, Kai-Chung Cheng c, Neil E. Klepeis c, Wayne R. Ott c, Lynn M. Hildemann, which is available on Research Gate, you'll find a comparison of indoor and outdoor PM2.5 for 66 casinos, plotted on a log-normal plot.  As you can see, both distributions fit the log-normal distribution very well.  

Giwa, there is a Software called Emisens, it estimates uncertainties from road traffic emissions, please check this PhD thesis: http://infoscience.epfl.ch/record/149809/files/EPFL_TH4793.pdf. You can also contact Professor Alain Clappier, he developed this Software: alain.clappier@live-cnrs.unistra.fr

@Rosaline

After your last entry I understand much better what you are after. However, the area of heterogeneous conversion of NOx is a very tricky one. My main experience is the interaction with walls of smog chambers. It appears that the presence of a surface water layer is essential. However, I think that up till today there is not a good kinetic description for the interconversions taking place in such a rather well-defined environment. A amin issue is the formation of nitrous acid. This is a key compound for starting the photochemical cycle. Of course this is of more importance at sites where photochemistry occurs

 There is also the interaction of nitric (and sulfuric) acid with seasalt, but this reaction is fast and occurs already in the aerosol in the air.

By the way did you have a look at the literature on the heterogeneous / surface reactions of the compounds?

ISORROPIA only provides equilibria but the question for you obviously is how fast?