Particle size, characterization

A. Hickey, Factors influencing aerosol desposition in inertial impactors and their effect on particle size characterization, Pharm, Tech. (Sept. 1990), pp. 118-120. 

The extraction of more complex particle size distributions from PCS data (which is not part of the commonly performed particle size characterization of solid lipid nanoparticles) remains a challenging task, even though several corresponding mathematical models and software for commercial instruments are available. This type of analysis requires the user to have a high degree of experience and the data to have high statistical accuracy. In many cases, data obtained in routine measurements, as are often performed for particle size characterization, are not an adequate basis for a reliable particle size distribution analysis. 

Transmission electron microscopy (TEM) has been an underutilized yet valuable too in particle size characterization of MC particles in LB films. Monolayer films of trioctylphosphine oxide-capped CdSe (18), spread as a monolayer on an aqueous subphase, were transferred to a TEM grid. A close-packed hexagonal arrangement of 5.3-nm (cr —4%) crystallites was found. TEM images were also obtained for HMP-stabilized CdS incorporated in BeH/octadecylamine films (79) and for CdS formed under an amine-based surfactant monolayer and transferred to a TEM grid (14). In one study, direct viewing of CdS and CdSe particles made from Cd2+-FA films on TEM grids was not possible due to poor phase contrast between the particles and the film (30). Diffraction patterns were observed, however, that were consistent with crystalline (3-CdS or CdSe. Approximately spherical particles of CdSe could... 

Laser diffraction is the most commonly used instrumental method for determining the droplet size distribution of emulsions. The possibility of using laser diffraction for this purpose was realized many years ago (van der Hulst, 1957 Kerker, 1969 Bohren and Huffman, 1983). Nevertheless, it is only the rapid advances in electronic components and computers that have occurred during the past decade or so that has led to the development of commercial analytical instruments that are specifically designed for particle size characterization. These instruments are simple to use, generate precise data, and rapidly provide full particle size distributions. It is for this reason that they have largely replaced the more time-consuming and laborious optical and electron microscopy techniques. 

Jillavenkatesa A, Dapkunas SJ, Lum HLS. 2001. Special Publication 960-1 Particle size characterization. Washington, DC NIST 165. 

Heffel, C., Heitzmann, D., Kramer, H., and Scarlett, B. (1995), paper presented at the 6th European Symp. Particle Size Characterization, Partec 95, Nurenberg, Germany. 

Raman spectroscopy UV/visible spectroscopy Acoustic Emission spectroscopy Particle size characterization X-ray tomography NMR... 

Jillavenkatesa, A., Dapkunas, S.J. and Lum,L-S. H. (2001), Particle size characterization. National Institute of Standards and Technology, NIST Sp. Publ. 960-1, 12... 

Particle Size Characterization, Partec 95, Numberg, Germany, publ. NumbergMesse GmbH, 315-325, 55... 

Particle Size Characterization, Partec 95, NUmberg, Germany, publ. 

Loffler-Mang, M. and Wollny, M. (1998), 7 European Symp. Particle Size Characterization, Partec 98, NUmberg, Germany, publ. NumbergMesse GotZ)//.571-580, 470... 

Sensors for particle size characterization used for crystallization include ultrasound attenuation measurement/ " laser diffraction/ and laser backscatteiing/ commercially called focused beam reflectance measurement (FBRM). Ultrasonic attenuation spectroscopy has been used to monitor the crystallization process parameters such as the crystal size distribution, concentration, and the onset of nucleation during batch crystallization of L-glutamic acid/ Off-line laser diffraction has been used to measure the crystal size distribution in the development of the crystallization process for a pharmaceutical intermediate/ ... 

Crystallization General Principles and Significance on Product Development, p. 834. Particle-Size Characterization, p. 2582. Polymorphism Pharmaceutical Aspects, p. 2935. Spectroscopic Methods of Analysis Infrared Spectroscopy, p. 3405. 

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