scholarly journals Chemical source profiles of fine particles for five different sources in Delhi

Chemosphere ◽  
2021 ◽  
Vol 274 ◽  
pp. 129913
Author(s):  
Sarkawt Hama ◽  
Prashant Kumar ◽  
Mohammed S. Alam ◽  
Daniel J. Rooney ◽  
William J. Bloss ◽  
...  
Keyword(s):  
Fine Particles ◽  
Source Profiles ◽  
Different Sources

scholarly journals The Effects of Calcination on Mineral Composition and Physical Properties of Limestones and Oyster Shells Derived from Different Sources

2021 ◽  
Vol 11 (4) ◽  
pp. 578-586
Author(s):  
Khalil . ◽  
Ridho Kurniawan Rusli ◽  
Andri .
Keyword(s):  
Physical Properties ◽  
Mineral Composition ◽  
Fine Particles ◽  
Oyster Shell ◽  
Angle Of Repose ◽  
Chemical Compositions ◽  
Mineral Concentration ◽  
Tapped Density ◽  
Different Sources ◽  
Decomposition Properties

Limestones and oyster shells are normally used in raw or roasted meal form in the livestock diet. Calcination is intended to improve the mineral concentration and physical characteristics of limestones and oyster shells which vary based on different chemical compositions, textures, and impurities of their types and habitats. The present research aimed to study the effects of calcination on mineral composition and the physical properties of limestones and oyster derived from various sources. Limestone samples from three local limestone mining and oyster shell samples from three shellfish species were calcined by burning at a temperature of 800-1000°C. The calcined products were analyzed for mineral content (Ca, P, Mg, Cu, Zn, and Mn), physical properties (bulk density, tapped density, specific density, and angle of repose), and particle size. Results indicated that calcination had no significant effect on Ca and P concentrations but reduced micro mineral concentration. Limestones had a higher Mg concentration than that of oyster shells, and calcination increased Mg concentration. Calcined oyster shells had higher densities, percentages of fine particles, and lower angles of response. The results suggested that the type of limestones and oyster shells could determine their thermal decomposition properties.

scholarly journals Wildfire smoke impacts respiratory health more than fine particles from other sources: observational evidence from Southern California

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Rosana Aguilera ◽  
Thomas Corringham ◽  
Alexander Gershunov ◽  
Tarik Benmarhnia
Keyword(s):  
Particulate Matter ◽  
Air Quality ◽  
Human Health ◽  
Fine Particles ◽  
Respiratory Health ◽  
Fine Particulate Matter ◽  
Health Concern ◽  
Wildfire Smoke ◽  
Toxicological Studies ◽  
Different Sources

AbstractWildfires are becoming more frequent and destructive in a changing climate. Fine particulate matter, PM2.5, in wildfire smoke adversely impacts human health. Recent toxicological studies suggest that wildfire particulate matter may be more toxic than equal doses of ambient PM2.5. Air quality regulations however assume that the toxicity of PM2.5 does not vary across different sources of emission. Assessing whether PM2.5 from wildfires is more or less harmful than PM2.5 from other sources is a pressing public health concern. Here, we isolate the wildfire-specific PM2.5 using a series of statistical approaches and exposure definitions. We found increases in respiratory hospitalizations ranging from 1.3 to up to 10% with a 10 μg m−3 increase in wildfire-specific PM2.5, compared to 0.67 to 1.3% associated with non-wildfire PM2.5. Our conclusions point to the need for air quality policies to consider the variability in PM2.5 impacts on human health according to the sources of emission.

scholarly journals SSH-Aerosol v1.1: A Modular Box Model to Simulate the Evolution of Primary and Secondary Aerosols

Atmosphere ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 525
Author(s):  
Karine Sartelet ◽  
Florian Couvidat ◽  
Zhizhao Wang ◽  
Cédric Flageul ◽  
Youngseob Kim
Keyword(s):  
Organic Compounds ◽  
Fine Particles ◽  
3D Models ◽  
Climate Modelling ◽  
Aerosol Dynamics ◽  
Particle Mixing ◽  
Secondary Aerosols ◽  
Ultra Fine Particles ◽  
Different Sources ◽  
Chamber Measurements

Particles are emitted by different sources and are also formed in the atmosphere. Despite the large impact of atmospheric particles on health and climate, large uncertainties remain concerning their representation in models. To reduce these uncertainties as much as possible, a representation of the main processes involved in aerosol dynamics and chemistry is necessary. For that purpose, SSH-aerosol was developed to represent the evolution of the mass and number concentrations of primary and secondary particles, across different scales, using state-of-the-art modules, taking into account processes that are usually not considered in air-quality or climate modelling. For example, the particle mixing state and the growth of ultra-fine particles are taken into account in the aerosol dynamics, the affinity of semi-volatile organic compounds with water and viscosity are taken into account in the partitioning between the gas and particle phases of organics and the formation of extremely low-volatility organic compounds from biogenic precursors is represented. SSH-aerosol is modular and can be used with different levels of complexity. It may be used as standalone to analyse chamber measurements. It is also designed to be easily coupled to 3D models, adapting the level of complexity to the spatial scale studied.

A Study on Characterization of Biomass Fly Ash

2019 ◽  
Vol 891 ◽  
pp. 137-141
Author(s):  
Jirasak Tharajak ◽  
Noppakun Sanpo
Keyword(s):  
Fly Ash ◽  
Research Study ◽  
Fine Particles ◽  
Flue Gases ◽  
Experimental Result ◽  
Result Section ◽  
Industrial Boiler ◽  
Biomass Fly Ash ◽  
Different Sources

Biomass fly ash is an ash combustion product. It is composed of the particulates (fine particles of fuel) driven out of biomass-fired boilers together with the flue gases. The understanding of the behaviour and property of fly ash is very important in order to predict the consumable part lifetime inside industrial boiler system. In this research study, the several characterization processes were carried out. It was revealed that biomass fly ash obtained from different sources presented unique property and more results were displayed in experimental result section.

scholarly journals PM2.5Emission Elemental Composition from Diverse Combustion Sources in the Metropolitan Area of Mexico City

2008 ◽  
Vol 8 ◽  
pp. 275-286 ◽  
Author(s):  
V. Mugica ◽  
F. Mugica ◽  
M. Torres ◽  
J. Figueroa
Keyword(s):  
Fine Particles ◽  
Chemical Species ◽  
Trace Element Content ◽  
Waste Incineration ◽  
Emission Source ◽  
Carbon Ions ◽  
Gas Combustion ◽  
Source Profiles ◽  
Combustion Sources ◽  
Heavy Duty Diesel

A field study was carried out from 2003 to 2004 with the aim to develop the PM2.5emission source profiles from light-duty gasoline and heavy-duty diesel vehicles, as well as emission source profiles from waste incineration, wood burning, LP gas combustion, and meat broiling. Over 25 chemical species were quantified from the fine particles emitted by the different combustion sources investigated, including organic and elemental carbon, ions, and elements. The OC/TC ratio found in the different PM2.5profiles was dissimilar as well as the sulfate, nitrate, ammonium, soil species, and trace element content. Consequently, these combustion emission profiles could be used in source reconciliation studies for fine particles.

The 'well-known' theory of electron image formation

1983 ◽  
Vol 41 ◽  
pp. 288-289
Author(s):  
M.A. O'Keefe ◽  
W.O. Saxton
Keyword(s):  
Image Processing ◽  
Image Formation ◽  
Source Profiles ◽  
Electron Image

A recent paper by Kirkland on nonlinear electron image processing, referring to a relatively new textbook, highlights the persistence in the literature of calculations based on incomplete and/or incorrect models of electron imageing, notwithstanding the various papers which have recently pointed out the correct forms of the appropriate equations. Since at least part of the problem can be traced to underlying assumptions about the illumination coherence conditions, we attempt to clarify both the assumptions and the corresponding equations in this paper, illustrating the effects of an incorrect theory by means of images calculated in different ways.The first point to be made clear concerning the illumination coherence conditions is that (except for very thin specimens) it is insufficient simply to know the source profiles present, i.e. the ranges of different directions and energies (focus levels) present in the source; we must also know in general whether the various illumination components are coherent or incoherent with respect to one another.

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.

Sign in / Sign up

Export Citation Format

Share Document