Three-wavelength light transmission technique to measure smoke particle size and concentration

1979 ◽  
Vol 18 (11) ◽  
pp. 1763 ◽  
Author(s):  
Kenneth L. Cashdollar ◽  
Calvin K. Lee ◽  
Joseph M. Singer
Keyword(s):  
Particle Size ◽  
Light Transmission ◽  
Smoke Particle ◽  
Transmission Technique ◽  
Wavelength Light

The Distribution with Respect to Smoke Particle Size of Dotriacontane, Hexadecane and Decachlorobiphenyl Added to Cigarettes

1975 ◽  
Vol 8 (2) ◽  
Author(s):  
R. T. Jones ◽  
W. G. D. Lugton ◽  
S. R. Massey ◽  
R. B. Richardson
Keyword(s):  
Particle Size ◽  
Particulate Matter ◽  
Smoke Particle ◽  
Selective Effects

AbstractWhen studying the distribution of smoke deposited in the lung, it is necessary to use a tracer which indicates the levels of particulate matter deposited at various sites. Because the site of deposition can be dependent on the particle size of the aerosol, it is important that the tracer should be uniformly distributed with respect to particle size, otherwise the levels of particulate matter may be wrongly estimated. The distributions in the smoke from a cigarette containing flue-cured tobacco of three possible tracers (dotriacontane, hexadecane and decachlorobiphenyl) have been measured; alI three show a slight dependence but probably not sufficient to exclude them from possible use in inhalation studies. However, because of the different environment which exists in the lung, and the possible dependence of the results on the type of tobacco, it should not be assumed that there are no selective effects

scholarly journals Modulation of Lithium Disilicate Translucency through Heat Treatment

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2094
Author(s):  
Seok-Ki Jung ◽  
Dae Woon Kim ◽  
Jeongyol Lee ◽  
Selvaponpriya Ramasamy ◽  
Hyun Sik Kim ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Particle Size ◽  
Light Scattering ◽  
Flexural Strength ◽  
Control Method ◽  
Light Transmission ◽  
Lithium Disilicate ◽  
Lower Heat ◽  
Average Size ◽  
Ball Test

The aim of this study was to present a control method for modulating the translucency of lithium disilicate ceramics through thermal refinement. Identical lithium disilicate blocks were thermally refined using four different heat treatment schedules, and the microstructure, translucency, and flexural strength of the ceramics were investigated in detail by SEM, spectroscopy, and a piston-on-three-ball test. The results showed that ceramics treated under higher heat had larger grains, with an average size between 240 and 1080 nm. In addition, a higher transmittance of all wavelengths was observed in ceramics treated under lower heat, and the transmittance in the 550 nm wavelength ranged from 27 to 34%. The results suggest that the translucency of ceramics can be modified through thermal refinement under two conditions: (1) the particle size of the ceramic is small enough to achieve minimal grain-boundary light scattering, and (2) the percentage of particles allowing visible light transmission is altered by the heat treatment.

Classification and quantification of downslope erosion from a geosynthetic clay liner (GCL) when covered only by a black geomembrane

2015 ◽  
Vol 52 (4) ◽  
pp. 395-412 ◽  
Author(s):  
R.W.I. Brachman ◽  
A. Rentz ◽  
R.K. Rowe ◽  
W.A. Take
Keyword(s):  
Classification System ◽  
Soil Cover ◽  
Light Transmission ◽  
Test Site ◽  
Field Observations ◽  
Composite Liner ◽  
Geosynthetic Clay Liner ◽  
Clay Liner ◽  
Transmission Technique ◽  
Field Investigations

Field observations of downslope bentonite erosion from a geosynthetic clay liner (GCL) covered by only a black geomembrane are reported for a composite liner left exposed without a protective soil cover for much longer than recommended by the GCL manufacturer. A new nondestructive, light-transmission technique developed to investigate bentonite erosion features in the field is presented. A classification system is developed to describe the type of erosion features observed. Results from five field investigations at the Queen’s University Environmental Liner Test Site (QUELTS II) are reported to quantify the onset, progression, and severity of downslope erosion for one particular geotextile-encased, needle-punched GCL for exposure periods of between 7 weeks and 1.3 years. The first significant erosion feature (type “E”with bentonite loss narrower than 2.5 cm) was observed after 6 months of exposure. Irrecoverable erosion features (type “EE” with bentonite loss wider than 2.5 cm) were observed after 12 months of exposure. These findings highlight the need to follow the manufacturer’s recommendations for timely covering of a composite liner with soil following liner installation.

scholarly journals IN VITRO ANTI-PLATELET AGGREGATION ACTIVITY OF HYDROXYPROPYL CELLULOSE–CYSTEAMINE BASED NANOPARTICLES CONTAINING CRUDE BROMELAIN

2020 ◽  
pp. 95-98
Author(s):  
DENI RAHMAT ◽  
LILIEK NURHIDAYATI ◽  
MARCELLA MARCELLA ◽  
ROS SUMARNY ◽  
DIAN RATIH LAKSMITAWATI
Keyword(s):  
Particle Size ◽  
Platelet Aggregation ◽  
Zeta Potential ◽  
Light Transmission ◽  
Hydroxypropyl Cellulose ◽  
Platelet Activity ◽  
Two Samples ◽  
Significant Difference ◽  
Aggregation Activity

Objective: The aim of the present study was to formulate bromelain into nanoparticles in order to improve its stability and activity. Methods: Crude bromelain was prepared by protein precipitation from the pineapple stem juice using ammonium sulphate at the concentration of 60% (w/v). Nanoparticles containing crude bromelain were generated using the ionic gelation method with hydroxypropyl cellulose–cysteamine (HPC-cysteamine) conjugate as a matrix. Crude bromelain was then added to the HPC-cysteamine solution for ionic interaction to construct the nanoparticles, which were then analyzed for their particle size and zeta potential. The resulting nanoparticles were mixed with adenosine diphosphate (ADP) to perform anti-platelet aggregation. Results: The nanoparticle had 928.3 nm in particle size and-7.25 mV in zeta potential. Anti-platelet activity of crude bromelain and the nanoparticles were determined with modification of light transmission aggregometry (LTA), in which ADP was used to induce an aggregation while a spectrophotometer UV-Vis was used to measure the absorbance at the wavelength of 600 nm. The result showed that crude bromelain and the nanoparticles rendered percentage inhibition of 8.00±1.17% and 48.56±11.19%, respectively. Conclusion: Based on the result of a one-way analysis of variance (ANOVA), it was concluded that there was a significant difference in percentage inhibition between the two samples. The nanoparticles demonstrated a better anti-platelet aggregation activity compared to crude bromelain.

scholarly journals Wildfire Smoke Particle Properties and Evolution, From Space-Based Multi-Angle Imaging II: The Williams Flats Fire during the FIREX-AQ Campaign

2020 ◽  
Vol 12 (22) ◽  
pp. 3823
Author(s):  
Katherine T. Junghenn Noyes ◽  
Ralph A. Kahn ◽  
James A. Limbacher ◽  
Zhanqing Li ◽  
Marta A. Fenn ◽  
...  
Keyword(s):  
Particle Size ◽  
Biomass Burning ◽  
In Situ Measurements ◽  
Statistical Characterization ◽  
Smoke Particle ◽  
Particle Properties ◽  
In Situ Data ◽  
Particle Property ◽  
Aircraft Data

Although the characteristics of biomass burning events and the ambient ecosystem determine emitted smoke composition, the conditions that modulate the partitioning of black carbon (BC) and brown carbon (BrC) formation are not well understood, nor are the spatial or temporal frequency of factors driving smoke particle evolution, such as hydration, coagulation, and oxidation, all of which impact smoke radiative forcing. In situ data from surface observation sites and aircraft field campaigns offer deep insight into the optical, chemical, and microphysical traits of biomass burning (BB) smoke aerosols, such as single scattering albedo (SSA) and size distribution, but cannot by themselves provide robust statistical characterization of both emitted and evolved particles. Data from the NASA Earth Observing System’s Multi-Angle Imaging SpectroRadiometer (MISR) instrument can provide at least a partial picture of BB particle properties and their evolution downwind, once properly validated. Here we use in situ data from the joint NOAA/NASA 2019 Fire Influence on Regional to Global Environments Experiment-Air Quality (FIREX-AQ) field campaign to assess the strengths and limitations of MISR-derived constraints on particle size, shape, light-absorption, and its spectral slope, as well as plume height and associated wind vectors. Based on the satellite observations, we also offer inferences about aging mechanisms effecting downwind particle evolution, such as gravitational settling, oxidation, secondary particle formation, and the combination of particle aggregation and condensational growth. This work builds upon our previous study, adding confidence to our interpretation of the remote-sensing data based on an expanded suite of in situ measurements for validation. The satellite and in situ measurements offer similar characterizations of particle property evolution as a function of smoke age for the 06 August Williams Flats Fire, and most of the key differences in particle size and absorption can be attributed to differences in sampling and changes in the plume geometry between sampling times. Whereas the aircraft data provide validation for the MISR retrievals, the satellite data offer a spatially continuous mapping of particle properties over the plume, which helps identify trends in particle property downwind evolution that are ambiguous in the sparsely sampled aircraft transects. The MISR data record is more than two decades long, offering future opportunities to study regional wildfire plume behavior statistically, where aircraft data are limited or entirely lacking.

Measurement of Smoke Particle Size and Distribution Within a Gas Turbine Combustor

2005 ◽  
Vol 127 (2) ◽  
pp. 286-294 ◽  
Author(s):  
K. D. Brundish ◽  
M. N. Miller ◽  
C. W. Wilson ◽  
M. Jefferies ◽  
M. Hilton ◽  
...  
Keyword(s):  
Particle Size ◽  
Gas Turbine ◽  
Fluid Dynamic ◽  
Combustion Process ◽  
Analytical Techniques ◽  
Number Concentration ◽  
Operating Conditions ◽  
Fuel Injector ◽  
Gas Turbine Combustor ◽  
Smoke Particle

The objective of the work described in this paper was to identify a method of making measurements of the smoke particle size distribution within the sector of a gas turbine combustor, using a scanning mobility particle sizing (SMPS) analyzer. As well as gaining a better understanding of the combustion process, the principal reasons for gathering these data was so that they could be used as validation for computational fluid dynamic and chemical kinetic models. Smoke mass and gaseous emission measurements were also made simultaneously. A “water cooled,” gas sampling probe was utilized to perform the measurements at realistic operating conditions within a generic gas turbine combustor sector. Such measurements had not been previously performed and consequently initial work was undertaken to gain confidence in the experimental configuration. During this investigation, a limited amount of data were acquired from three axial planes within the combustor. The total number of test points measured were 45. Plots of the data are presented in two-dimensional contour format at specific axial locations in addition to axial plots to show trends from the primary zone to the exit of the combustor. Contour plots of smoke particle size show that regions of high smoke number concentration once formed in zones close to the fuel injector persist in a similar spatial location further downstream. Axial trends indicate that the average smoke particle size and number concentration diminishes as a function of distance from the fuel injector. From a technical perspective, the analytical techniques used proved to be robust. As expected, making measurements close to the fuel injector proved to be difficult. This was because the quantity of smoke in the region was greater than 1000mg/m3. It was found necessary to dilute the sample prior to the determination of the particle number concentration using SMPS. The issues associated with SMPS dilution are discussed.

Measurement of Smoke Particle Size and Distribution Within a Gas Turbine Combustor

2003 ◽  
Author(s):  
K. D. Brundish ◽  
M. N. Miller ◽  
C. W. Wilson ◽  
M. Hilton ◽  
M. P. Johnson ◽  
...  
Keyword(s):  
Particle Size ◽  
Gas Turbine ◽  
Fluid Dynamic ◽  
Combustion Process ◽  
Analytical Techniques ◽  
Number Concentration ◽  
Operating Conditions ◽  
Fuel Injector ◽  
Gas Turbine Combustor ◽  
Smoke Particle

The objective of the work described in this paper was to identify a method of making measurements of the smoke particle size distribution within the sector of a gas turbine combustor, using a Scanning Mobility Particle Sizing (SMPS) analyser. As well as gaining a better understanding of the combustion process, the principal reasons for gathering these data was so that they could be used as validation for Computational Fluid Dynamic (CFD) and chemical kinetic models. Smoke mass and gaseous emission measurements were also made simultaneously. A “water cooled,” gas sampling probe was utilised to perform the measurements at realistic operating conditions within a generic gas turbine combustor sector. Such measurements had not been previously performed and consequently initial work was undertaken to gain confidence in the experimental configuration. During this investigation, a limited amount of data were acquired from three axial planes within the combustor. The total number of test points measured were 45. Plots of the data are presented in 2 dimensional contour format at specific axial locations in addition to axial plots to show trends from the primary zone to the exit of the combustor. Contour plots of smoke particle size show that regions of high smoke number concentration once formed in zones close to the fuel injector persist in a similar spatial location further downstream. Axial trends indicate that the average smoke particle size and number concentration diminishes as a function of distance from the fuel injector. From a technical perspective, the analytical techniques used proved to be robust. As expected, making measurements close to the fuel injector proved to be difficult. This was because the quantity of smoke in the region was greater than 1000 mg/m3. It was found necessary to dilute the sample prior to the determination of the particle number concentration using SMPS. The issues associated with SMPS dilution are discussed.

scholarly journals Solute transport by suspended buoyant particles

2021 ◽  
Vol 249 ◽  
pp. 09002
Author(s):  
Iván Colecchio ◽  
Natalia Arze ◽  
Georgina Flores ◽  
Ana Quijandria ◽  
Alejandro Boschan
Keyword(s):  
Solute Transport ◽  
Solid Fraction ◽  
Light Transmission ◽  
Solute Concentration ◽  
Suspended Particles ◽  
Sharp Interface ◽  
Transmission Technique ◽  
Fingering Instability ◽  
Mass Discharge ◽  
Hele Shaw Cell

The transport of a colouring solute, driven by the buoyant displacement of microscopic suspended particles, and in the absence of net flow, is studied experimentally in a Hele Shaw cell. Initially, a sharp interface between a transparent fluid without particles and an underlying coloured suspension is obtained. From this situation, the suspended particles rise, carrying the solute in the form of a fingering instability across the interface, where a light transmission technique is used to measure the local solute concentration. This one attains an asymptotic value that increases with the solid fraction ϕ of suspended particles, and decreases with the distance to the interface. The solute mass discharge also increases with ϕ, always being relatively small (< 3%). The onset and development of the instability as the mechanism driving the transport of the solute is discussed.

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