PARTICLE SIZE ANALYSIS Particle size analysis is a method or part of laboratory techniques of finding the size range and or the usual mean size of the particles in a residue or in a liquid substance. This method is belong in a ‘particle science’ and its determination is carried out usually in ‘particle technology’ laboratories. Particle size influences many properties of particulate materials and is a valuable indicator of quality and performance. This is true for powders, suspensions, emulsions, and aerosols. The size and shape of powders influences flow and compaction properties.. Powder or droplets in the range of 2-5μm aerosolize better and will penetrate into lungs deeper than larger sizes. For these and many other reasons it is important …show more content…
Large particles are light that are scatterred at small angles relative to the laser beam and small particles scatter light at large angles. Anlyzation will be processed in the angular scattering intensity data so that the size of the particles responsible for creating the scattering pattern can be calculated. Mie theory of light scattering to calculate the particle size distribution is used in light diffraction, assuming a volume equivalent sphere model. Mie theory requires knowledge of the optical properties of both the sample being measured. Usually the optical properties of the dispersant are relatively easy to find from published data, and many modern instruments will have in-built databases that include common dispersants. For samples where the optical properties are not known, the user can either measure them or estimate them using an iterative approach based upon the goodness of fit between the modeled data and the actual data collected for the sample. Laser Diffraction Particle Size Analysis (Particle size range 0.02-2000µm). Photon Correlation Spectroscopy (Particle size range :1nm to
...the mass spectrometer. This is called an electron impact source. Gases and volatile liquid samples are allowed to leak into the ion source from a reservoir. Non-volatile solids and liquids may be introduced directly. Cations formed by the electron bombardment (red dots) are pushed away by a charged repeller plate (anions are attracted to it), and accelerated toward other electrodes, having slits through which the ions pass as a beam. Some of these ions fragment into smaller cations and neutral fragments. A perpendicular magnetic field deflects the ion beam in an arc whose radius is inversely proportional to the mass of each ion. Lighter ions are deflected more than heavier ions. By varying the strength of the magnetic field, ions of different mass can be focused progressively on a detector fixed at the end of a curved tube. Because the mass of each individual ion
Using the scopula, take a small amount of the substance and add it to the spot plate. Add deionized water to the section with the substance. Stir to see if the substance dissolves or not. Record your observations.
In the case of solids, by reducing particle size and thus
Ultrafine particles can be defined as nano-sized particles which is less than 100nm. However, it is not manufactured purposely and not inevitably exist in a constant size. It is also known to be appeared by friction or combustion process, natural process in the air or water. (United States Environmental Protection Agency, 2013). Besides that, ultrafine particles can be described as the smallest fraction in a scale of airborne particles with diameters ranging from a few nanometers to several nanometers. Even they are small particles in size, they are dominant contributors to particle number even it is capable to contribute little to the mass of particulate matter in ambient air. (Health Effects Institute, 2013). They are also represent about 80% of particles in terms of number concentration in an urban environment (Morawska et al., 1998). There are variety of sources of ultrafine particles. According to Cess et al (2000), the major sources of ultrafine particles is from combustion process which is comprised of vehicle emission, stationary sources fuel combustion, non-highway mobile sources such as diesel off-road vehicles, and other mixed emission from open
There is considerable literature indicating a link between particulate matter and cardiovascular morbidity and mortality, especially in elderly individuals (Koken, et al, 2003). Particulate matter defined as any particle that measures less than or equal to ten micrometers (< 10µm PM10) or two point five micrometers(< 2.5µm PM2.5) that form from solid particles and liquid droplets. Most particulate matter forms due to vehicle admissions, industrials processes or wood burnings. Additionally, it has also been suggested that ultra fine particulate matter measuring less than or equal to 2.5 µm is considered more harmful to health than are larger particles in aerodynamic diameter because PM2.5 can penetrate deeper into the lung than PM10 (Park, et al, 2010).
Polman, H., Orobio De Castro, B. & Van Aken, M. A.G. (2008). Experimental Study of the
The number and strength of collisions is increased so that the reaction can happen faster than it should. If the particles have more energy then more particles will be able to react to it. Solid reactants like marble chips are affected by surface area. The larger the surface area, the more collisions that will take place.
Aerosol is a system of solid or liquid particles suspended in air or other gaseous environment. Aerosols vary in size and composition, they can be naturally or manmade generated. Aerosols are minute particles suspended in the atmosphere. When these particles are sufficiently large, we notice their presence as they scatter and absorb sunlight. Aerosols interact directly and indirectly with the earth’s radiation budget and climate. In direct effect the aerosols scatter sunlight. In indirect effect the aerosol can modify the size of cloud.
Even materials containing small amounts of crystalline silica may be hazardous if they are used in ways that produce high dust concentrations.
Serway, Raymond A, and Robert J Beichner. Physics: For Scientists and Engineers. United States of
It is a type of analytical technique. It measures the mass to charge ratio of charged particles, it is used to determine masses of particles. It is used to determine the elemental composition of a sample. we can say how it helps in castings, by using this technique how much percentage of raw materials needed to prepare particular alloy castings.
American Institute of Physics. Vol. 1051 Issue 1 (2008). Academic Search Premier.> 224. http://login.ezproxy1.lib.asu.edu/login?url=http://search.ebscohost.com.ezproxy1.lib.asu.edu/login.aspx?direct=true&db=aph&AN=34874307&site=ehost-live.
Some lasers are as large as buildings while others can be the size of a grain
[ IMAGE] 3. What is the difference between a'smart' and a's Size of solid particles (or surface area) increases collisions. If one of the reactants is a solid than break it up into smaller pieces will increase their surface area. This means that the particles around it in the solution will have more area to work on. so there will be more useful collisions.