The study of elements or particles that are not of the same nature is carried out using scientific instruments. Such instruments are used for characterizing the size of a particle, zeta potential, rheology, porosity, solid content in concentrated dispersions such as slurries (CMP, ceramic & battery), pharmaceutical emulsions, cements etc. Porous bodies are also a part of these concentrated dispersions. A particle size is the dimension of an element which is determined with the help of particle size analyzers. There are several methods used for this purpose for example, the process of sedimentation results in comparable hydrodynamic particle size and microscopy provides the information about the dimension of elements on area projection. The measurement is based on numerical, area and weight. There are three categories of a particle size analyzer namely counters, fraction methods and macroscopic fitting methods. Light scattering, x-rays scattering and neutron scattering are done using acoustic spectroscopy which falls in third category that is, macroscopic fitting methods. The dimensions are calculated on the basis of weight which is innate only for acoustic spectroscopy. The reduction in the strength of ultrasound caused by a single particle is in proportion of the weight or volume of the particle. In Acoustic Spectroscopy, the measurement of an element does not require dilution and sample preparation as in many cases dilution affects the PSD or particle size distribution. Acoustic also examines the presence of nano-particulates with precision of 1%. Industries dealing in pharmaceuticals, cement, ceramic, paints and emulsions practice these measurement methods. In porous bodies, streaming potential and steaming current take place when liquid passes through them. This process which is also termed as electro-kinetic phenomena is used for studying zeta potential in porous materials. This method is mainly used in the paper industry where steaming potential is preferred to find the measurement. The concept of streaming potential & current is applied in seismoelectric effect. This phenomenon occurs in underground rocks when sound waves travel through them. The reason behind conducting this activity is to find the underground formations and presence of water or oil. To calculate the wet-ability of absorbent elements, DT-3—zeta potential probe is used which utilizes streaming current. Streaming current and streaming potential are also helpful in monitoring and controlling the quality of chromatographic resins. The contact of resins with proteins is controlled by Zeta potential of the pores which permits optimization of protein treatment. Other than this, the technique of measuring the current flow also provides useful information of structure in carbon nano-tubes dispersions. About the Author- Dispersion Technology Inc. started in year 1996. The company develops instruments for characterizing the size of particle using particle size analyzer and studying the concentrated complex liquid systems.
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Dispersion Technology developing analytical instrumentation suitable for characterizing concentrated complex liquid systems, such as slurries, pharma,
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