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Showing 1 to 11 of 11 for “"nephelometer"”.
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Entwicklung eines optischen Messgeräts zur Erfassung der Struktur von Eispartikeln sowie der winkelaufgelösten Streuung im sichtbaren Spektralbereich
… wurde ein neuartiges abbildendes Einzelpartikel-Nephelometer entwickelt. Es verwendet eine ultraschnelle Weißlicht-Blitzlampe zur Hellfeld-Beleuchtung einzelner luftgetragener Eiskristalle, die mit einer CCD-Kamera vergrößert abgebildet werden. Gleichzeitig wird die Streufunktion der Kristalle …
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Wireless Dust Sensor Network for a Feedlot Dust Abatement Study
… A small, inexpensive, portable, wireless nephelometer dust sensor was developed using a low-cost, commercial optical sensing module. A second dust sensor was developed that samples air by the method of impaction of a dust-air stream into a water droplet capturing images using a low-cost …
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Physical and Chemical Properties of Laboratory and Ambient Aerosols Related to Climate Change
… RH scanning nephelometry system. Correcting for nephelometer non-idealities and RH of the sample improved the agreement between measured and predicted total scattering coefficients (sigmasp) at RH = 80% from 35% to 11%. The closure experiment revealed the importance of keeping the nephelometry …
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A Study of Asian Dust Events Using Surface, Satellite, and Aircraft Measurements During Intex-B
… at 588 nm and a depolarization of 25%. The DC-8 nephelometer also observed this dust event in-situ and confirmed that the highest scattering coefficient ranged from 80-100 mm'1. When this dust transported to North America, its AOD values decreased from a mean of 2.0 over the source region to 0.2 …
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Direct Aerosol Radiative Forcing Based on Optical Measurements at Contrasting, Climatically Important Sites
… of light were measured using a controlled RH nephelometer system. Results from Cape Grim demonstrated the predominate influence of sea-salt aerosol in regard to all aerosol optical properties and for both sub- and super-micrometer Dp size cuts. At Sagres, polluted aerosol predominated and even …
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Data Interpretation and Management for an Atmospheric Probe Mission to Venus
… scientific instrument, the Autofluorescence Nephelometer (AFN), will gather data by measuring the light scattering off particles, providing insight into their chemical composition based on refractive index and particle size [Baumgardner et al., 2022]. Unfortunately, the natural phenomena …
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The Effect of Aerosols on Radiative Transfer and the Optical Properties of the Atmosphere
… (ELSIE) model and an open-air integrating nephelometer. The annual-mean species concentrations showed that the most abundant identifiable species is sulfate assumed to be ammonium sulfate (annual-mean concentration 5.72 $\mu$g/m$\sp3$) followed by organic carbon (3.16 $\mu$g/m$\sp3$), …
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Investigation of the Chemical and Physical Properties of Asian Dust and Asian Pollution Transpacific Transport During the Intex-B Field Campaign
… ratios at 450, 550 and 700 nm as measured by the nephelometer demonstrates whether the plume contains fine mode aerosols; which is believed to be an excellent indicator of whether the Asian dust plume is carrying any pollution along its transport pathway. Based on the wavelength dependence, three …
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Composition and characteristics of particles in the ocean : evidence for present day resuspension
… Iceland Rise area the correlation of the L-DGO nephelometer to concentration of SPM differs between clear water and the nepheloid layer. Correlations of light scattering to SPM concentration also differ regionally, but for predicting concentration from light scattering, regression lines at two …
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Development Of A Supercontinuum Based Photoacoustic Aerosol Light Absorption And Albedo Spectrometer (PALAAS)
Aerosols are a major contributor to the global radiation budget because they modify the planetary albedo with their optical properties. These optical properties need to be measured and understood, ideally at multiple wavelengths. This thesis describes the ongoing development of a supercontinuum …
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Airborne lidar observations of tropospheric arctic clouds
… Furthermore, in situ observations with the Polar Nephelometer, Cloud Particle Imager and Forward Scattering Spectrometer Probe (Laboratoire de Météorologie Physique, France) provided information on the microphysical properties, cloud particle size and shape, concentration, extinction, liquid and …