Study of particle resuspension from dusty surfaces using a centrifugal method

Indoor Air ◽  
2019 ◽  
Vol 29 (5) ◽  
pp. 791-802 ◽  
Author(s):  
Hau Him Lee ◽  
Yung Shan Cheung ◽  
Sau Chung Fu ◽  
Christopher Y. H. Chao
Keyword(s):  
Particle Resuspension ◽  
Centrifugal Method

103. Use of Acoustical Energy for Particle Resuspension

2000 ◽  
Author(s):  
S. Azadi ◽  
A. Afshari ◽  
D. Frazer
Keyword(s):  
Particle Resuspension ◽  
Acoustical Energy

CFD Simulation of Particle Transport and Dispersion in Indoor Environment by Human Walking

2012 ◽  
Author(s):  
Iman Goldasteh ◽  
Goodarz Ahmadi ◽  
Andrea Ferro
Keyword(s):  
Particulate Matter ◽  
High Speed ◽  
Cfd Simulation ◽  
Three Dimensional ◽  
Study Data ◽  
Turbulent Dispersion ◽  
Experimental Chamber ◽  
Indoor Environments ◽  
Three Dimensional Model ◽  
Particle Resuspension

Particle resuspension is an important source of particulate matter in indoor environments that significantly affects the indoor air quality and could potentially have adverse effect on human health. Earlier efforts to investigate indoor particle resuspension hypothesized that high speed airflow generated at the floor level during the gate cycle is the main cause of particle resuspension. The resuspended particles are then assumed to be dispersed by the airflow in the room, which is impacted by both the ventilation and the occupant movement, leading to increased PM concentration. In this study, a three dimensional model of a room was developed using FLUENT™ CFD package. A RANS approach with the RNG k-ε turbulence model was used for simulating the airflow field in the room for different ventilation conditions. The trajectories of resuspended particulate matter were computed with a Lagrangian method by solving the equations of particle motion. The effect of turbulent dispersion was included with the use of the eddy lifetime model. The resuspension of particles due to gait cycle was estimated and included in the computational model. The dispersion and transport of particles resuspended from flooring as well as particle re-deposition on flooring and walls were simulated. Particle concentrations in the room generated by the resuspension process were evaluated and the results were compared with experimental chamber study data as well as simplified model predictions, and good agreement was found.

Aerodynamic Particle Resuspension Due to Human Foot and Model Foot Motions

2013 ◽  
Vol 47 (2) ◽  
pp. 208-217 ◽  
Author(s):  
Yoshihiro Kubota ◽  
Hiroshi Higuchi
Keyword(s):  
Particle Resuspension ◽  
Human Foot

Monte Carlo modelling of particle resuspension on a flat surface

2015 ◽  
Vol 79 ◽  
pp. 126-139 ◽  
Author(s):  
J.G. Benito ◽  
K.A.Valenzuela Aracena ◽  
R.O. Uñac ◽  
A.M. Vidales ◽  
I. Ippolito
Keyword(s):  
Monte Carlo ◽  
Flat Surface ◽  
Particle Resuspension

scholarly journals Dispersal of persistent organic pollutants from fiber-contaminated sediments: biotic and abiotic pathways

2021 ◽  
Author(s):  
Anna-Karin Dahlberg ◽  
Anna Apler ◽  
Paul Frogner-Kockum ◽  
Gunnel Göransson ◽  
Ian Snowball ◽  
...  
Keyword(s):  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
River Estuary ◽  
Contaminated Sediments ◽  
The Body ◽  
Passive Samplers ◽  
The Other ◽  
Sediment Surface ◽  
Average Particle ◽  
Particle Resuspension

Abstract Purpose Numerous sites contaminated with fiber emissions from pulp and paper industries are found in coastal areas of the Baltic Sea, but there is limited knowledge about the magnitude of dispersal of persistent organic pollutants (POPs) from these anthropogenic, organic-rich sediments called fiberbanks. The aim of this study was to quantify and compare different POP dispersal pathways from such fiberbanks. Dispersal mechanisms studied included abiotic and biotic routes (dissolved in water, particle-bound, and bioaccumulation). Materials and methods Contaminated fibrous sediments located in Ångermanälven River estuary in north-eastern Sweden were studied in sediment types representing different fiber content (i.e., fiberbanks, fiber-rich sediments, and less fiber impacted sediments). Sediment-to-water fluxes of dissolved contaminants (polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and dichlorodiphenyltrichloroethane (DDT)) were measured in situ using benthic flux chambers. Particle resuspension was measured by sampling bottom water, before and after disturbing the sediment surface. Benthic biota was collected to determine the body burden of contaminants and to determine biota-pore water accumulation factors (BAFPW) and biota-sediment accumulation factors (BSAFs). In addition, concentrations of dissolved POPs in the water column were measured in field using passive samplers. Instrumental analysis was performed using gas chromatography coupled to a triple quadrupole mass spectrometer (GC-MS/MS). Results and discussion The flux of dissolved Σ20PCBs was approximately two times higher from one of the investigated fiberbanks (3.4 ng m− 2 day− 1) compared to the other. The average particle burden of PCBs was also higher at this fiberbank after artificial disturbance (15 ng g−1 particle), which indicates that larger amounts of contaminants are likely to disperse via particle resuspension from this site compared to the other fiberbank (4.8 ng g− 1 particle). The difference might be associated with a layer of recently settled minerogenic material that covers one of the fiberbanks, which probably functions as a protective barrier. The lack of benthic biota implies that contaminant release by bioturbation is negligible in the studied fiberbanks. However, benthic biota from fiber-rich sediment showed bioaccumulation and biomagnification of contaminants. Conclusions The importance of diffusive flux from fiberbanks under undisturbed conditions became apparent when the different dispersal pathways were quantified. However, no dispersal pathway could be judged as irrelevant, since even under undisturbed conditions, advective particle transport was significant. Additionally, the uptake by biota and trophic transfer can be considerable. Quantification of dispersal routes and understanding of the relative importance of various pathways is critical for proper risk assessment and management of contaminated sediments.

Health hazard in the spinning of viscose rayon textile yarn by the centrifugal method

1978 ◽  
Vol 10 (1) ◽  
pp. 37-39
Author(s):  
A. P. Martynova ◽  
L. P. Golyakova ◽  
A. N. Zelenkin ◽  
E. I. Polyakov
Keyword(s):  
Viscose Rayon ◽  
Health Hazard ◽  
Textile Yarn ◽  
Rayon Textile ◽  
Centrifugal Method

Isolation Of Plasma Membrane Vesicles Of Human Platelet By Affinity Chromatography

1981 ◽  
Author(s):  
T Kobayashi ◽  
M Sakon ◽  
H Ohno ◽  
J Kambayshi ◽  
G Kösaki
Keyword(s):  
Plasma Membrane ◽  
Affinity Chromatography ◽  
Morphological Changes ◽  
Membrane Vesicles ◽  
Dry Weight ◽  
Appreciable Amount ◽  
Marker Enzyme ◽  
Plasma Membrane Vesicles ◽  
Platelet Suspension ◽  
Centrifugal Method

Platelets undergo a unique morphological changes leading to the formation of hemostatic plug. In recent years, its intermediaty metabolism has been extensively studied and the important function of plasma membrane in the platelet reaction has been recognized. The method of Barber and Jamieson has been employed in order to prepare plasma membrane vesicles of platelet of excellent quality but it is rather time consuming and the yield is relatively low. In this study, an attempt was made to isolate plasma membrane vesicles of human platelets by wheat germ agglutinin affinity chromatography.Freshly collected human citrated blood was subjected to glycerol loading and hypotonic lysis to obtain lysed platelet suspension. Then, it was applied to the affinity chromatography and the fraction of plasma membrane vesicles was eluted by 0.2 M N-acetyl glucosamine. Electron micrograph of the fraction showed round membrane vesicles with some scattered intracellular organelles. Several marker enzymes were assayed in the fraction. No appreciable amount of β-glucuronidase or cytochrome c oxidase was detected in the fraction, indicating no contamination of mitochondria or α-granules. Relatively high activity of G-6-Pase was detected, suggesting possible contamination of endoplasmic reticulum. The yield was 11.6% in dry weight and 7.9% in protein.By this method, the isolation was much faster than the centrifugal method and as low as 20 ml of human citrated whole blood may be used as starting material. Upon characterization of the plasma membrane fraction by electron microscopy and marker enzyme assays, the quality of the fraction was found comparable with the centrifugal method. The yield by this method was approximately two times higher than by the conventional method.

SEPARATION OF SWELLING CLAY MINERALS BY A CENTRIFUGAL METHOD

1966 ◽  
pp. 407-418 ◽  
Author(s):  
DARRELL C. BUSH ◽  
RALPH E. JENKINS ◽  
STANLEY B. MCCALEB
Keyword(s):  
Clay Minerals ◽  
Swelling Clay ◽  
Centrifugal Method ◽  
Swelling Clay Minerals
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