scholarly journals STUDY OF SAMPLES STRENGTH OF MATERIAL FORMED BY THE PROCESSES OF COMPACTION, EXTRUSION AND TUMBLING GRANULATION

2019 ◽  
Vol 59 (5) ◽  
pp. 490-497
Author(s):  
Peter Peciar ◽  
Radovan Ružinský ◽  
Adam Guštafík ◽  
Mária Karľová ◽  
Matúš Čierny ◽  
...  
Keyword(s):  
Fine Particles ◽  
Cement Kiln ◽  
Fine Dust ◽  
Brake Pads ◽  
Industrial Expansion ◽  
Energy Processing ◽  
Dust Treatment

In a period of industrial expansion, protection of the environment is often neglected during the mass manufacture of products. One of the problems of our society that is necessary to face at present is the provision, processing and then usage of waste composed of fine particles that are extremely dangerous for mankind. This study looks at the processing of the fine dust resulting from the manufacture of brake pads. The selected technologies for the process of dust treatment were compaction, extrusion and tumbling granulation, and their consequent comparison with the strength of a break and disintegration of agglomerates from fine dust. The experiments were performed on a unique equipment that made it possible to process such dust in the form of larger units and thus reduce their dustiness, with this dust being reintroduced into the technologies for repeat processing or used for energy processing, in a cement kiln, for example.

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 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 Particle Morphology, Composition and Associated Ice Chemistry of Tephra Layers in the Byrd Ice Core: Evidence for Hydrovolcanic Eruptions

1985 ◽  
Vol 7 ◽  
pp. 42-48 ◽  
Author(s):  
J.M. Palais
Keyword(s):  
Fine Particles ◽  
Ice Core ◽  
Particle Morphology ◽  
Dust Particles ◽  
Fine Dust ◽  
West Antarctica ◽  
Climatic Impact ◽  
Glacier Ice ◽  
Tephra Layers ◽  
Ice Chemistry

In 1968 an ice core 2164 m long was recovered from Byrd station in West Antarctica. About 2000 tephra layers were observed in the core and have been differentiated into ash and dust bands according to the grain size and concentration of particles in the layers. Mount Takahe, a local volcano in Marie Byrd Land, Antarctica is the probable source. Detailed examinations of the particle morphology, composition and ice chemistry associated with some of the tephra layers have led to the conclusion that the eruptions which produced the layers were probably hydrovolcanic. Melted glacier ice is considered the most likely source of the water involved in the eruptions. Processes associated with hydrovolcanism such as particle aggregation (causing premature deposition of fine particles), rapid conversion of sulfur dioxide to sulfuric acid (in the presence of abundant moisture) and scavenging of acid droplets by the fine dust particles are inferred to have taken place. Such processes would greatly reduce the atmospheric residence time of the eruptive products and thus their atmospheric and climatic impact.

scholarly journals We will not Get Rid of Coronaviruses without Creating a True Sustainable Development Model

2020 ◽  
Keyword(s):  
Forest Fires ◽  
Fine Particles ◽  
Natural Habitat ◽  
The Elderly ◽  
Emerging Countries ◽  
Real Problem ◽  
Fine Dust ◽  
Entire World ◽  
Monitoring Software ◽  
World Development

If it is true that covid-19 comes from wild animals that have lost their natural habitat due to deforestation and large forest fires and savannas; if it is true that the mortality of those affected increases exponentially in the areas with higher percentages of fine dust, Nox, Sox, CO, in the atmosphere; if it is true that the most affected are the elderly, what does this have to do with the European call for startups dedicated to the Covid-19 emergency, which expired on 18 March, intended above all for small and medium-sized enterprises for innovative contributions useful for cope with any aspect of the emergency? The budget for this call is 164 million euros. What is this rain of millions on small and medium-sized enterprises? At most, they can develop some control and monitoring software for people who move around the area. This is already being done in China and Korea. Since we are late, we may also be able to import this software from these countries. Why, as Europeans, do we not focus on the real problem that affects the entire world development? Emerging countries, such as China and Korea, have made the mistake of copying our energy and purification solutions, even surpassing us by the amount of pollution produced. EUROPE should anticipate the immediate decarburization of energy, the modification of urban purification systems (we cannot continue to wait for the rains to reduce fine particles).

scholarly journals Particle Morphology, Composition and Associated Ice Chemistry of Tephra Layers in the Byrd Ice Core: Evidence for Hydrovolcanic Eruptions

1985 ◽  
Vol 7 ◽  
pp. 42-48 ◽  
Author(s):  
J.M. Palais
Keyword(s):  
Fine Particles ◽  
Ice Core ◽  
Particle Morphology ◽  
Dust Particles ◽  
Fine Dust ◽  
West Antarctica ◽  
Climatic Impact ◽  
Glacier Ice ◽  
Tephra Layers ◽  
Ice Chemistry

In 1968 an ice core 2164 m long was recovered from Byrd station in West Antarctica. About 2000 tephra layers were observed in the core and have been differentiated into ash and dust bands according to the grain size and concentration of particles in the layers. Mount Takahe, a local volcano in Marie Byrd Land, Antarctica is the probable source.Detailed examinations of the particle morphology, composition and ice chemistry associated with some of the tephra layers have led to the conclusion that the eruptions which produced the layers were probably hydrovolcanic. Melted glacier ice is considered the most likely source of the water involved in the eruptions.Processes associated with hydrovolcanism such as particle aggregation (causing premature deposition of fine particles), rapid conversion of sulfur dioxide to sulfuric acid (in the presence of abundant moisture) and scavenging of acid droplets by the fine dust particles are inferred to have taken place. Such processes would greatly reduce the atmospheric residence time of the eruptive products and thus their atmospheric and climatic impact.

scholarly journals An Experimental Study on Performance and Structural Improvements of a Novel Elutriator

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 478
Author(s):  
Jipeng Dong ◽  
Pan Zhang ◽  
Weiwen Wang ◽  
Jianlong Li ◽  
Guanghui Chen
Keyword(s):  
Gas Flow ◽  
Fine Particles ◽  
Separation Efficiency ◽  
Particle Dispersion ◽  
Operating Conditions ◽  
Separation Performance ◽  
Fine Dust ◽  
Fire Hazards ◽  
Feeding Speed ◽  
Air Speed

During the transportation and packaging of low density polyethylene (LDPE) granular materials, fine dusts such as floccules, powder and fiber will be produced, which pollute the environment, affect product quality and generate fire hazards. In this work, the separation performance of fine dust and optimal operating conditions of an improved elutriator were investigated experimentally. Experiments were carried out to investigate the effects of air speed, feeding speed, and grid layout on the removal efficiency of fine particles. Experimental data showed that the separation efficiency of the novel elutriator ranged from 96% to 98.50%, which was more stable and an average of 51.44% higher than that of the original elutriator. By setting internals and improving the structure, the gas flow field in the equipment was regulated, the particle dispersion was intensified, and the static electricity was eliminated, which significantly improved the separation efficiency of fine dust.

Formation of Physic and Mechanical Composition of Dust Emission from the Ventilation Shaft of a Coal Mine as a Factor of Ecological Hazard

2018 ◽  
Vol 277 ◽  
pp. 178-187 ◽  
Author(s):  
Valeriy Kolesnyk ◽  
Artem Pavlychenko ◽  
Olena Borysovs’ka ◽  
Yuriy Buchavyy
Keyword(s):  
Coal Mine ◽  
Fine Particles ◽  
Coal Mines ◽  
Dust Emission ◽  
Fine Dust ◽  
Ventilation Shaft ◽  
Dust Fraction ◽  
Mine Workings ◽  
Ecological Hazard ◽  
Mineral Product

During operation of coal mines, polluted air is emitted from the ventilation shafts, it contains large amount of carbon and rock dust with various physical and mechanical composition. Dust contains freshly formed silicon dioxide and other components of the mineral product that are hazardous to human health, which are scattered in the surface layer of the atmosphere. Mainly fine dust comes from the mine workings, and the release of the total dust mass by 80 – 96 % is due to the operation of the loading and unloading complex. It is established that the level of dustiness decreases mainly due to the settling in the mine workings of the coarsely dispersed dust fraction. The environment receives mainly fine dust with a high content of fine particles, which can be intensively dispersed outside the sanitary protection zone of the mine. A mathematical model is obtained in the form of a differential equation of mass transfer, which takes into account the physic and mechanical composition of the dust emission from the ventilation shaft of the coal mine as a factor of ecological hazard. The obtained results determine the directions of effective struggle against dust emissions of coal mines.

Cytoplasmic Organization in the Receptor Cells of the Crista Ampullaris

1972 ◽  
Vol 30 ◽  
pp. 60-61 ◽  
Author(s):  
Robert F. Dunn
Keyword(s):  
Fine Particles ◽  
Apical Cell ◽  
Apical Region ◽  
Receptor Cells ◽  
Cuticular Plate ◽  
Morphological Organization ◽  
Crista Ampullaris ◽  
Cytoplasmic Organization ◽  
High Degree ◽  
General Appearance

Receptor cells of the cristae in the vestibular labyrinth of the bullfrog, Rana catesbiana, show a high degree of morphological organization. Four specialized regions may be distinguished: the apical region, the supranuclear region, the paranuclear region, and the basilar region.The apical region includes a single kinocilium, approximately 40 stereocilia, and many small microvilli all projecting from the apical cell surface into the lumen of the ampulla. A cuticular plate, located at the base of the stereocilia, contains filamentous attachments of the stereocilia, and has the general appearance of a homogeneous aggregation of fine particles (Fig. 1). An accumulation of mitochondria is located within the cytoplasm basal to the cuticular plate.

Bright-Field Images (Ctem) of Phase Objects at High Resolution

1976 ◽  
Vol 34 ◽  
pp. 490-491 ◽  
Author(s):  
Sumio Iijima
Keyword(s):  
High Resolution ◽  
Electron Beam Irradiation ◽  
Fine Particles ◽  
High Resolution Electron Microscopy ◽  
Good Test ◽  
Resolution Electron ◽  
Single Crystal Films ◽  
Crystal Films ◽  
By Products ◽  
Test Objects

We have developed a technique to prepare thin single crystal films of graphite for use as supporting films for high resolution electron microscopy. As we showed elsewhere (1), these films are completely noiseless and therefore can be used in the observation of phase objects by CTEM, such as single atoms or molecules as a means for overcoming the difficulties because of the background noise which appears with amorphous carbon supporting films, even though they are prepared so as to be less than 20Å thick. Since the graphite films are thinned by reaction with WO3 crystals under electron beam irradiation in the microscope, some small crystallites of WC or WC2 are inevitably left on the films as by-products. These particles are usually found to be over 10-20Å diameter but very fine particles are also formed on the film and these can serve as good test objects for studying the image formation of phase objects.

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