Particle size distribution of workplace aerosols in manganese alloy smelters applying a personal sampling strategy

2015 ◽  
Vol 17 (12) ◽  
pp. 2066-2073 ◽  
Author(s):  
B. Berlinger ◽  
M. D. Bugge ◽  
B. Ulvestad ◽  
H. Kjuus ◽  
K. Kandler ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Sampling Strategy ◽  
Manganese Alloy ◽  
Air Samples ◽  
Personal Sampling ◽  
Cascade Impactors

Air samples were collected by personal sampling with five stage Sioutas cascade impactors and respirable cyclones in parallel among tappers and crane operators in two manganese (Mn) alloy smelters in Norway to investigate PM fractions.

A Simplified Model for the Flow Inside Cascade Impactor

2013 ◽  
Author(s):  
Seyyed Mahdi Nemati Mehr ◽  
Salman Sohrabi ◽  
Pedram Falsafi ◽  
Paniz Gorji
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Low Cost ◽  
Mass Difference ◽  
Cascade Impactor ◽  
Computational Method ◽  
Simplified Model ◽  
Unit Value ◽  
Cascade Impactors

In this paper we developed a new mathematical model for the flow inside cascade impactors and via this simplified model, we determined the particle size distribution by a fast and low cost computational method. Using cascade impactors for determining the particle size distribution, one can use comprehensive CFD methods to fully simulate the particle traces. Although the results from those CFD analyses can be very accurate, usually that is not a time and cost efficient routine. In contrast, we showed that by using our proposed calculation we can estimate the particle size distribution very fast and yet with the slight error — comparing to the results from CFD method. Cascade impactors are being used to measure the range of substances moving through an opening and determine the particle size of distributed substances. Air flow containing aerosol entering in each stage, after colliding vertically with a plate will deviate 90 degrees from its original direction. Larger (massive) particles cannot follow the flow because of their larger linear momentum. Hence, they will deviate from the flow and deposit on the plate instead. The mass difference before and after the experiment represents the deposited mass in each stage. By integrating multiple uniquely designed stages into one impactor, we can determine size of particles in the flow. Typical cascade impactors consist of up to ten stages in which different size of aerosols are being separated. This paper presents a simple model for the flow in one single stage of a cascade impactor. Flow inside cascade impactor is approximated by stagnation point potential flow with the stream function of Psi = Axy, and particles are tracked by velocity verlet algorithm. Absorbed particles are associated with unit value; otherwise they are associated with zero. It is assumed that particles in entrance have random size distribution and location. Drag, Saffman and Brownian forces are taken into account in this model for different particle sizes. The results are discussed in detail and compared with data driven from different approaches in the literature.

EVALUATION OF AERODYNAMIC PARTICLE SIZE DISTRIBUTION OF DRUGS USED IN INHALATION THERAPY: A CONCISE REVIEW

2020 ◽  
Vol 8 (7) ◽  
pp. 264-271
Author(s):  
Smita Nayak ◽  
Priyanka Ghugare ◽  
Bhaskar Vaidhun
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Dry Powder Inhaler ◽  
Dose Inhaler ◽  
Metered Dose Inhaler ◽  
Aerodynamic Particle Size Distribution ◽  
Metered Dose ◽  
Aerodynamic Particle Size ◽  
Cascade Impactors

Most of the inhalation products in the market use metered dose inhaler (MDI) technology or dry powder inhaler (DPI) technology. MDIs use propellant to deliver desired dose of liquid formulation in aerosol form. DPI contains active in fine particulate form embedded onto an inert carrier. In both cases, amount of drug dispensed from the device reaching the lungs is dependent upon drug product characteristics as well as formulation-device relationship. Hence, in addition to particle size, aerodynamic distribution of the drug upon delivery by the device plays an important role in determining amount of drug reaching the lungs. Therefore particle size characterization is an important tool in determining the extent of drug delivery from the metered dose inhaler. Aerodynamic particle size distribution is frequently determined by use of cascade impactors and data so generated is accepted by regulatory agencies as a tool for predicting efficacy of MDIs and DPIs. This review discusses principle and working of cascade impactors. Additionally, the review also examines the role of laser diffraction technique in estimating size of dispersed particles.

Effects of Particle Size Distribution on Corrosion Rate of Carbon Steel in Soil

2020 ◽  
Vol 69 (4) ◽  
pp. 102-106
Author(s):  
Shota Ohki ◽  
Shingo Mineta ◽  
Mamoru Mizunuma ◽  
Soichi Oka ◽  
Masayuki Tsuda
Keyword(s):  
Particle Size ◽  
Carbon Steel ◽  
Corrosion Rate ◽  
Particle Size Distribution ◽  
Size Distribution

DENSE SPRAY CORRECTIONS FOR DIFFRACTION-BASED PARTICLE SIZE DISTRIBUTION MEASUREMENTS

1995 ◽  
Vol 5 (1) ◽  
pp. 75-87 ◽  
Author(s):  
Christine M. Woodall ◽  
James E. Peters ◽  
Richard O. Buckius
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution

Influence of Cementite Particle Size Distribution on Machinability and Tool Life of High Carbon Cr-bearing Steels

1998 ◽  
Vol 84 (5) ◽  
pp. 387-392 ◽  
Author(s):  
Takashi INOUE ◽  
Yuzo HOSOI ◽  
Koe NAKAJIMA ◽  
Hiroyuki TAKENAKA ◽  
Tomonori HANYUDA
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Tool Life ◽  
Cementite Particle ◽  
High Carbon ◽  
Bearing Steels
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