scholarly journals Effect of thermal conductivity on gravitational instability of quantum plasma having fine dust particles

2013 ◽  
pp. 32
Author(s):  
Vijayendra Shrivastava ◽  
Ashok Kumar Patidar ◽  
Ram Kumar Pensia
Keyword(s):  
Thermal Conductivity ◽  
Gravitational Instability ◽  
Dust Particles ◽  
Quantum Plasma ◽  
Fine Dust

PHYTOMONITORING AS A METOD OF THE ASSESSMENT OF ATMOSPHERIC AIR POLLUTION BY URBAN ENVIRONMENT BY FINE DUST

2019 ◽  
pp. 42-53
Author(s):  
Irina Glinyanova ◽  
Valery Azarov ◽  
Valery Fomichev
Keyword(s):  
Urban Environment ◽  
Urban Areas ◽  
Fine Particles ◽  
Prunus Armeniaca ◽  
Dust Particles ◽  
Fine Dust ◽  
Control Zone ◽  
Atmospheric Air ◽  
Random Functions ◽  
The City

Fine dust: (PM2.5, PM10) is a priority pollutant that contributes to the development of numerous dis-eases in urban areas. The purpose of this scientific work is to study the dispersed composition of dust parti-cles on the leaves of apricot trees (Prúnus armeníaca) in the residential zone of Volgograd. The novelty of the work lies in the study of the dispersed composition of dust particles on the leaves of apricot trees (Prúnus armeníaca) in the residential zone in the city of Volgograd near the construction industry enterprise, me-chanical engineering, leather production and railway transport line in comparison with the conditionally clean (control) zone of the SNT “Orocenets” ”(Sovetsky District, Volgograd) from the standpoint of random functions expressed by integral distribution curves of the mass of particles over their equivalent diameters. As a result of the research, the dispersed composition of dust on the leaves of apricot trees (Prúnus ar-meníaca) in the residential area of Volgograd was revealed. Fine particles were found: PM2.5, PM10 in each of the studied points, which by their values, both in their number and mass fraction, significantly exceed the data on fine dust in a conditionally clean area (control) in the SNT “Oroshanets” (Sovetsky district Volgo-grad), which creates certain environmental risks for local residents. The dispersed analysis of particles from the standpoint of random functions in the future will allow with a sufficiently high degree of accuracy to pre-dict the dust content of urban atmospheric air in the range of monthly and / or seasonal average values compared to the traditional measurement of fine dust concentration in atmospheric air of the urban environ-ment as the maximum single or daily average. At the same time, further studies of dust on the leaves of plants in an urban environment, namely, the study of the density of its sedimentation, will also reveal a group of ur-ban plants that are best suited to retain PM2.5 and PM10 on leaf plates in this region, which can significantly increase the quality of the atmospheric air of the urban environment and be of a recommendatory nature for the state-owned landscaping services of the city of Volgograd when improving the green areas of a megacity.

scholarly journals Quantitative analysis of fine dust particles on moss surfaces under laboratory conditions using the example of Brachythecium rutabulum

2021 ◽  
Author(s):  
Bilitis Désirée Vanicela ◽  
Martin Nebel ◽  
Marielle Stephan ◽  
Christoph Riethmüller ◽  
Götz Theo Gresser
Keyword(s):  
Fine Fraction ◽  
Model Organism ◽  
Dust Particles ◽  
Quantitative Detection ◽  
Suitable Model ◽  
Fine Dust ◽  
Sem Images ◽  
Moss Species ◽  
Laboratory Conditions ◽  
Number Of Particles

AbstractThe identification of a model organism for investigations of fine dust deposits on moss leaflets was presented. An optical method with SEM enabled the quantitative detection of fine dust particles in two orders of magnitude. Selection criteria were developed with which further moss species can be identified in order to quantify the number of fine dust particles on moss surfaces using the presented method. Among the five moss species examined, B. rutabulum had proven to be the most suitable model organism for the method presented here. The number of fine dust particles on the moss surface of B. rutabulum was documented during 4 weeks of cultivation in the laboratory using SEM images and a counting method. The fine dust particles were recorded in the order of 10 μm–0.3 μm, divided into two size classes and counted. Under laboratory conditions, the number of particles of the fine fraction 2.4 μm–0.3 μm decreased significantly.

The photography of fine dust particles

1939 ◽  
Vol 16 (8) ◽  
pp. 262-263 ◽  
Author(s):  
D G Beadle
Keyword(s):  
Dust Particles ◽  
Fine Dust

scholarly journals The influence of the thermal modification of pine ( Pinus sylvestris L.) wood on the creation of fine dust particles in plane milling

2019 ◽  
Vol 61 (6) ◽  
pp. 481-488 ◽  
Author(s):  
Magdalena Piernik ◽  
Tomasz Rogoziński ◽  
Andrzej Krauss ◽  
Grzegorz Pinkowski
Keyword(s):  
Pinus Sylvestris ◽  
Thermal Modification ◽  
Dust Particles ◽  
Fine Dust ◽  
The Creation

scholarly journals Fine dust atmospheric pollution from the objects of infill construction

2019 ◽  
Vol 135 ◽  
pp. 01020
Author(s):  
Svetlana Manzhilevskaya ◽  
Alexei Lihonosov ◽  
Lubov Petrenko
Keyword(s):  
Air Pollution ◽  
Fine Particles ◽  
Residential Buildings ◽  
Measurement Data ◽  
Anthropogenic Sources ◽  
Dynamic State ◽  
Dust Particles ◽  
Construction Site ◽  
Fine Dust ◽  
Protective Measures

Air pollution emissions are released from both natural and anthropogenic sources. During the environment pollution researching and monitoring the special attention should be paid to the construction operations, since during the construction processes many pollutants are released, especially fine dust particles, which are harmful to the health of construction workers and the population living near the construction site. The construction of any object in urban terrain has bad influence not only on the nearby buildings and city infrastructure, but on the existing environment of urban areas. The identification of the important pollution sources that contribute to ambient concentrations of pollutants is essential for developing an effective air quality management plan during building construction. Particular attention should be paid to emissions of fine particles during technological processes of construction with a special degree of dust emission. Control and regulation of the dynamic state of dispersed systems released during technological construction processes using a number of protective measures will reduce emissions of pollutants into the air. The objects of this research were the construction site and residential buildings of a large residential complex «Ekaterininskiy» located in Rostov-on-Don. The obtained measurement data as a result of this type of environmental monitoring showed the level of atmospheric air pollution from the construction industry using the example of the construction of the residential complex “Ekaterininskiy” in Rostov-onDon. After analyzing the situation with dust pollution the protective measures were suggested.

scholarly journals Linear analysis of the non-axisymmetric secular gravitational instability

2019 ◽  
Vol 487 (4) ◽  
pp. 5405-5415
Author(s):  
Mohsen Shadmehri ◽  
Razieh Oudi ◽  
Gohar Rastegarzadeh
Keyword(s):  
Amplification Factor ◽  
Gravitational Instability ◽  
Radial Distance ◽  
Dust Particles ◽  
Linear Perturbation ◽  
Model Parameters ◽  
Time Interval ◽  
Continuous Growth ◽  
Two Fluid ◽  
Axisymmetric Perturbations

Abstract In protoplanetary discs (PPDs) consisting of gas and dust particles, fluid instabilities induced by the drag force, including secular gravitational instability (SGI), can facilitate planet formation. Although SGI subject to the axisymmetric perturbations was originally studied in the absence of gas feedback and it then generalized using a two-fluid approach, the fate of the non-axisymmetric SGI, in either case, is an unexplored problem. We present a linear perturbation analysis of the non-axisymmetric SGI in a PPD by implementing a two-fluid model. We explore the growth of the local, non-axisymmetric perturbations using a set of linearized perturbation equations in a sheared frame. The non-axisymmetric perturbations display a significant growth during a finite time interval even when the system is stable against the axisymmetric perturbations. Furthermore, the surface density perturbations do not show the continuous growth but are temporally amplified. We also study cases where the dust component undergoes amplification whereas the gas component remains stable. The amplitude amplification, however, strongly depends on the model parameters. In the minimum mass solar nebula (MMSN), for instance, the dust fluid amplification at the radial distance 100 au occurs when the Stokes number is about unity. But the amplification factor reduces as the dust and gas coupling becomes weaker. Furthermore, perturbations with a larger azimuthal wavelength exhibit a larger amplification factor.

scholarly journals Climatic factors contributing to long-term variations of fine dust concentration in the United States

2017 ◽  
Author(s):  
Bing Pu ◽  
Paul Ginoux
Keyword(s):  
Great Plains ◽  
The United States ◽  
Dust Concentration ◽  
Dust Particles ◽  
Positive Trend ◽  
Fine Dust ◽  
Low Level ◽  
Low Level Jet ◽  
Long Term Variations

Abstract. High concentration of dust particles can cause respiratory problems and increase non-accidental mortality. Studies found fine dust (with aerodynamic diameter less than 2.5 microns) is an important component of the total PM2.5 mass in the western and central U.S. in spring and summer and has positive trends. This work examines factors influencing long-term variations of fine dust concentration in the U.S. using station data from the Interagency Monitoring Protected Visual Environments (IMPROVE) network during 1990–2015. The variations of the fine dust concentration can be largely explained by the variations of precipitation, surface bareness, and 10 m wind speed. Moreover, including convective parameters such as convective inhibition (CIN) and convective available potential energy (CAPE) better explains the variations and trends over the Great Plains from spring to fall. While the positive trend of fine dust concentration in the Southwest in spring is associated with precipitation deficit, the increasing of fine dust over the central Great Plains in summer is largely associated with an enhancing of CIN and a weakening of CAPE, which are related to increased atmospheric stability due to surface drying and lower troposphere warming. The positive trend of the Great Plains low-level jet also contributes to the increasing of fine dust concentration in the central Great Plains in summer via its connections with surface winds and CIN. Summer dusty days in the central Great Plains are usually associated with a westward extension of the North Atlantic subtropical high that intensifies the Great Plains low-level jet and also results in a stable atmosphere with subsidence and reduced precipitation.

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