Determination of the length and diameter of nanorods by a combination of analytical ultracentrifugation and scanning mobility particle sizer

Seit Anfang 2009 werden an einer städtischen Hintergrundmessstation in Mülheim-Styrum im westlichen Ruhrgebiet Anzahlkonzentration, Anzahlgrößenverteilung und lungendeponierbare Oberflächenkonzentration submikroner und ultrafeiner Partikel gemessen. Die dazu eingesetzten Messgeräte Scanning Mobility Particle Sizer (SMPS) und Nanoparticle Surface Area Monitor (NSAM) erwiesen sich als gut geeignet für derartige Messaufgaben. Insbesondere das NSAM ist sehr robust und zuverlässig und wird daher neben der Bestimmung der lungendeponierbaren Oberflächenkonzentration auch zur Funktionsüberwachung des SMPS verwendet. Die ultrafeinen Partikel an der Messstation stammen zu einem großen Teil von einer nahegelegenen Autobahn sowie diversen anderen Quellen in der näheren Umgebung. Der etwa 20 km südlich gelegene Flughafen Düsseldorf scheint keinen merklichen Einfluss zu haben. Eine Auswertung der Wochengänge zeigte überraschenderweise, dass in allen Jahren samstagnachts die im Wochenverlauf höchste Anzahlkonzentration von Partikeln >100 nm gemessen wurde. Während an allen anderen Wochentagen die mittleren Konzentrationen seit 2009 kontinuierlich gesunken sind, blieb die Höhe des Maximums in der Nacht von Samstag auf Sonntag nahezu konstant, was auf eine unveränderte, zeitlich sehr begrenzte Quelle hindeutet.

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Particle formation from pulsed laser irradiation of soot aggregates studied with a scanning mobility particle sizer, a transmission electron microscope, and a scanning transmission x-ray microscope

Applied Optics ◽

10.1364/ao.46.000959 ◽

2007 ◽

Vol 46 (6) ◽

pp. 959 ◽

Cited By ~ 50

Author(s):

Hope A. Michelsen ◽

Alexei V. Tivanski ◽

Mary K. Gilles ◽

Laura H. van Poppel ◽

Mark A. Dansson ◽

...

Keyword(s):

Electron Microscope ◽

Laser Irradiation ◽

Transmission Electron Microscope ◽

Pulsed Laser ◽

Scanning Mobility Particle Sizer ◽

X Ray ◽

Transmission Electron ◽

Scanning Transmission ◽

Particle Sizer ◽

Pulsed Laser Irradiation

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Measurement of nonvolatile particle number size distribution

Atmospheric Measurement Techniques ◽

10.5194/amt-9-103-2016 ◽

2016 ◽

Vol 9 (1) ◽

pp. 103-114 ◽

Cited By ~ 14

Author(s):

G. I. Gkatzelis ◽

D. K. Papanastasiou ◽

K. Florou ◽

C. Kaltsonoudis ◽

E. Louvaris ◽

...

Keyword(s):

Size Distribution ◽

Black Carbon ◽

Biomass Burning ◽

Particle Number ◽

Number Concentration ◽

Experimental Methodology ◽

Particle Number Concentration ◽

Scanning Mobility Particle Sizer ◽

Number Size Distribution ◽

Particle Sizer

Abstract. An experimental methodology was developed to measure the nonvolatile particle number concentration using a thermodenuder (TD). The TD was coupled with a high-resolution time-of-flight aerosol mass spectrometer, measuring the chemical composition and mass size distribution of the submicrometer aerosol and a scanning mobility particle sizer (SMPS) that provided the number size distribution of the aerosol in the range from 10 to 500 nm. The method was evaluated with a set of smog chamber experiments and achieved almost complete evaporation (> 98 %) of secondary organic as well as freshly nucleated particles, using a TD temperature of 400 °C and a centerline residence time of 15 s. This experimental approach was applied in a winter field campaign in Athens and provided a direct measurement of number concentration and size distribution for particles emitted from major pollution sources. During periods in which the contribution of biomass burning sources was dominant, more than 80 % of particle number concentration remained after passing through the thermodenuder, suggesting that nearly all biomass burning particles had a nonvolatile core. These remaining particles consisted mostly of black carbon (60 % mass contribution) and organic aerosol (OA; 40 %). Organics that had not evaporated through the TD were mostly biomass burning OA (BBOA) and oxygenated OA (OOA) as determined from AMS source apportionment analysis. For periods during which traffic contribution was dominant 50–60 % of the particles had a nonvolatile core while the rest evaporated at 400 °C. The remaining particle mass consisted mostly of black carbon with an 80 % contribution, while OA was responsible for another 15–20 %. Organics were mostly hydrocarbon-like OA (HOA) and OOA. These results suggest that even at 400 °C some fraction of the OA does not evaporate from particles emitted from common combustion processes, such as biomass burning and car engines, indicating that a fraction of this type of OA is of extremely low volatility.

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Osmotic Pressure and Phase Boundary Determination of Multiphase Systems by Analytical Ultracentrifugation

ChemPhysChem ◽

10.1002/cphc.200700668 ◽

2008 ◽

Vol 9 (6) ◽

pp. 882-890 ◽

Cited By ~ 7

Author(s):

Miles G. Page ◽

Thomas Zemb ◽

Monique Dubois ◽

Helmut Cölfen

Keyword(s):

Phase Boundary ◽

Osmotic Pressure ◽

Analytical Ultracentrifugation ◽

Boundary Determination ◽

Multiphase Systems

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Determination of coalescence stability of emulsions by analytical ultracentrifugation under separation of dispersed phase

Progress in Analytical Ultracentrifugation - Progress in Colloid & Polymer Science ◽

10.1007/bfb0115010 ◽

2007 ◽

pp. 76-83 ◽

Cited By ~ 6

Author(s):

K. Strenge ◽

A. Seifert

Keyword(s):

Analytical Ultracentrifugation ◽

Dispersed Phase

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Gross Morphological and Sex Wise Morphometrical Studies on Mandible of Adult Blue Bull (Boselaphus tragocamelus)

Indian Journal of Animal Research ◽

10.18805/ijar.b-4172 ◽

2021 ◽

Author(s):

S. Sathapathy ◽

B.S. Dhote ◽

S.K. Bharti ◽

I. Singh

Keyword(s):

Statistical Analysis ◽

Average Length ◽

T Test ◽

Average Thickness ◽

Legal Cases ◽

Recorded Data ◽

Mandibular Notch ◽

Horizontal Ramus ◽

Wild Life

Background: The Blue bull (Boselaphus tragocamelus) is one of the biggest antelopes in Asia and is widely distributed in both the forests and adjoining villages with enough green grass.Methods: The present study was carried out on the mandible of six specimens of adult Blue bull (Boselaphus tragocamelus) of either sex. The biometrical parameters were measured by scale, graduated tape and digital Vernier’s caliper. The statistical analysis of the recorded data was done by independent samples t-Test with Systat Software Inc, USA and SPSS 16.0 version software.Result: The mandible of Blue bull consisted of two rami, i.e. horizontal and vertical rami. The two halves of this bone fused incompletely at the mandibular symphysis, situated at the midline. The average length of horizontal ramus of mandible was found to be 24.7±1.02 cm in female, which was significantly less (P less than 0.05) than that of males, where it was recorded as 35.4±1.97 cm. Similarly, the average thickness of vertical ramus at the base was found to be 0.53±0.001 cm in female, which was significantly less (P less than 0.05) than that of males, where it was recorded as 0.80±0.002 cm. The average cranio-caudal length of mandibular notch was found to be 1.32±0.01 cm in female, which was significantly less (P less than 0.05) than that of males, where it was recorded as 1.44±0.02 cm. Most of the biometrical observations on different parameters of mandible of Blue bull were having significantly (P less than 0.05) more values in males than females. Conclusion: Most of the biometrical observations on different parameters of mandible of Blue bull were having significantly (p less than 0.05) more values in males than females. The present gross and biometrical studies would be useful to the wild life professionals for determination of sex of this animal and solving vetero-legal cases related with this species.

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