GRIMM CHANNELS Provided size Arith Bin Log Bin
GRIMM CHANNELS Provided size Arith Bin Log Bin channel Width width 0. 25 0. 28 0. 03 0. 049218 0. 3 0. 029963 0. 35 0. 066947 0. 4 0. 057992 0. 45 0. 051153 0. 5 0. 045757 0. 58 0. 064458 0. 65 0. 07 0. 049485 0. 7 0. 05 0. 032185 0. 8 0. 1 0. 057992 1 0. 2 0. 09691 1. 3 0. 113943 1. 6 0. 3 0. 090177 APS Channels Arith Midpoints 0. 523 0. 542 0. 583 0. 626 0. 673 0. 723 0. 777 0. 835 0. 898 0. 965 1. 037 1. 114 1. 197 UB 0. 523 0. 562126 0. 604118 0. 649075 0. 697552 0. 749514 0. 805478 0. 865927 0. 930897 1. 000352 1. 074811 1. 154755 1. 240702 OPS Channels Arith Bin Log Bin Width width 0. 039126 0. 041991 0. 044957 0. 048477 0. 051962 0. 055964 0. 060449 0. 06497 0. 069455 0. 074458 0. 079944 0. 085948 0. 03133 0. 03129 0. 03117 0. 03128 0. 03120 0. 03127 0. 03143 0. 03142 0. 03125 0. 03118 0. 03116 0. 03118 Arith Bin Log Bin Width width Mid. Points UB 0. 308 0. 369 0. 492 0. 656 0. 875 1. 167 1. 556 2. 0745 2. 7665 3. 6895 4. 92 6. 561 8. 7495 0. 316 0. 422 0. 562 0. 75 1 1. 334 1. 778 2. 371 3. 162 4. 217 5. 623 7. 499 10 0. 016 0. 106 0. 14 0. 188 0. 25 0. 334 0. 444 0. 593 0. 791 1. 055 1. 406 1. 876 2. 501 0. 022566 0. 125625 0. 124424 0. 125325 0. 124939 0. 125156 0. 124776 0. 12503 0. 125042 0. 124964 0. 125035 0. 124997 As shown above, APS and OPS are progressively increasing ‘linear’ bin widths yet equal ‘log’ bin widths with the exception of the 1 st bin of the OPS. In contrast and only displaying the first 12 bins of the GRIMM, illustrates the same linear widths for many of the channels (not shown) and thus non ‘equal’ log widths. For comparison with other instruments, It is imperative to at least compute the concentrations per log of the differential widths and preferable to construct new log bin widths and rebin counts prior to computation and graphical portrayal (as performed by the Doherty team during Sourceterm). This later technique is an option in the newer OPC counters (eg OPS) enabling custom bin widths to better match comparably with other instruments for comparison purposes.
Kaolin - APS Sample 11: 24 0. 1 Kaolin - APS Sample 11: 24 0. 35 0. 3 0. 25 0. 2 0. 15 0. 1 0. 05 0 1 10 100 0 0 2 4 6 8 10 These figures illustrates two points, yet here for the single express purpose to show the effect of graphical portrayal logarithmically (left) vs linearly (right). There is little difference in peak widths for the bins <1 micron yet progressively increase >2. This emphasizes/ graphically illustrates the effect of lack of resolution in the OPS when measuring larger particles (eg. There are just 3. 5 bins between 2 and 4 microns – peaks become wider when plotted linearly (right)). According to the literature, the OPS performs quite well in measuring particles < 1. 0 micron, the apparent primary academic area of interest. [Orange trace is an average of 5 vs a single discrete (blue) point from a concentration profile time plot – illustrating perhaps overreliance on a single sample of 6 or 20 sec with too statistically few particles]. 12 14
Kaolin at 11: 24 (without Dgeo conversion) to illustrate graphical portrayal in AIM of equal Log bins in column format as opposed to scatter. Not only does AIM display equal log bins by using Log scale but note the discontinuance between the lower bin (LB) of. 532 and the first bin at <. 523 (a gap between. 523 and. 532 an can be verified with a bit of number fun and the table above of size bins). Typically the first bin data is discarded due to this as well as that it contains unsized event 1 particles that do not elicit the second pulse in the time of flight signal. This bin, however is included in the total count of the AIM software. A linear x-axis display would result in progressive wider columns on the column graph.
When attempting to compare performances of various instruments, it is important to ‘first’ insure as much of a stable particle generation over time minimizing oscillations that could result (among others) from pressure and flow changes causing desorption and/or reaerosolizaton of particulates from the walls of the transport tube. The aerosol community frequently disseminates upto 30 min while monitoring instrument threshold concentration and stability prior to sampling. 1200 6000 #/cc > 0. 48 micron 14000 Total #/cc corrective to APS time for particles >~. 43 microns aps 1000 OPS 12000 GRIMM APS grimm 4000 600 3000 400 2500 10000 Total Conc (#/cc) #/cc TOTAL 800 3000 OPS 5000 2000 8000 1500 6000 2000 1000 4000 200 0 7: 12: 01 1000 7: 40: 49 8: 09: 37 8: 38: 25 9: 07: 13 9: 36: 01 10: 04: 49 0 3500 2000 0 8: 09: 37 8: 38: 25 9: 07: 13 9: 36: 01 10: 04: 49 10: 33: 37 Concentration time profiles for 4 test dusts (left) and 4 semi monodispersed materials (right). The material at the far left of the test dust plot is Alum Oxide and shows much ‘resemblance’ to sedimentation in a static chamber with the largest particles of the greatest mass settling first. A non-stable aerosol is not expected to be easily sampled and compared among multiple instuments. 0
1800 1600 APS 1400 Total (#/cc) mie pdr-1500 1200 1000 800 600 400 200 0 14: 49: 56 14: 57: 08 15: 04: 20 15: 11: 32 15: 18: 44 15: 25: 56 Conc mie PDR 1500 (mg/m^3) OPS 0 15: 33: 08 Likely a moot point since better settings for the acoustic disseminator (Angstrom sphere silica 10 -192016) have been found to achieve a more stable aerosol over time while comparing the total Number (APS and OPS) and mass conc(s) (PDR-1500). Material Optical parameters apparently have a significant difference. Parameters for Silicon dioxide (Silica Quartz) [1. 54 =n; 1. 3 e-8=k; shape factor (CF) =1. 25] were selected from ref literature (next slide). Shape factor was select from literature corresponding to sucrose particlates yet may be too large. Aps dae converted dgeo for silica was 1. 01 um compared with. 87 um before correction and 1. 08/09 (1. 54/1. 51 RI) um after correction (note angstrom sphere reports ~1. 38 - 1. 46 but at no wavelength which for the OPS is 660 nm).
http: //www. tsi. com/uploaded. Files/_Site_Root/Products/Literature/Posters/Han_OPS_poster_for_EAC 201 1 -8 P 291 -LTR. pdf Performance of a High Resolution Optical Particle Spectrometer HEE-SIEW HAN, Avula Sreenath, Nathan T. Birkeland, and George J. Chancellor TSI Incorporated, Shoreview, MN, USA Presented at the EAC 2011, Manchester, UK, September 2011 (Paper Number 8 P 291) https: //www. ncbi. nlm. nih. gov/pmc/articles/PMC 4667041/ Performance evaluation of newly developed portable aerosol sizers used for nanomaterial aerosol measurements Maromu YAMADA, 1, * Mitsutoshi TAKAYA, 1 and Isamu OGURA 2 2015 Nov; 53(6): 511– 516 https: //www. researchgate. net/publication/260335784_Comparison_of_a_New_Optical_Particle_Sizer_ to_Reference_Sizing_Instruments_for_Urban_Aerosol_Monitoring Comparison of a New Optical Particle Sizer to Reference Sizing Instruments for Urban Aerosol Monitoring Dr. Axel Zerrath, Dr. Michael Beeston, Oliver Bischof, Dr. Hans-Georg Horn, Dr. Thomas Krinke, TSI Gmb. H, Aachen, Germany Tim Johnson, Kathy Erickson, TSI Inc. , Shoreview, MN, USA Presented at “European Aerosol Conference 2011”, Manchester, UK [Correction factor estimation] 660 nm wavelength and 30 m. W laser power OPS RI=1. 5146 Siilca Quartz Silicon Dioxide (Silica Glass) N-BK 7 Schott http: //refractiveindex. info/? shelf=main&book=Si. O 2&page=Malitson http: //www. filmetrics. com/refractive-index-database/Si. O 2/Fused-Silica-Silicon-Dioxide-Thermal-Oxide-
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