Laboratory crystallizers

Complete descriptions of the particle beam, its operation, its experimental setup, and its utility in protein structural studies have been previously described. (8, 12). Relevant PB dimensions include a 25 pm diameter fused silica capillary for production of the aerosol spray, a 22 cm length desolvation chamber to remove solvent, a single stage momentum separator, and a nozzle-substrate distance of 5 mm. Particle beam deposits ranged in size from 20 pm to 100 pm in diameter, and averaged approximately 50 pm. Deposit were made onto a water insoluble calcium fluoride (CaFj) window (25 mm dia. x 2 mm) from International Crystal Laboratories (Garfield, NJ). 

Samples used in microscopes can be placed on the slide dry or wet. Typical liquids used for wet-immersion are non-aqueous based like Nujol (International Crystal Laboratories, Garfield, New Jersey, U.S.A.), which is liquid paraffin, or Sirax, which is cedar wood oil. Again, there are many practical aspects of preparing samples for microscopy and the requirement of proper microscope settings can be found in Refs. 7, 9, 40. 

This principle has been successfully utilized in an industrial application to achieve a small average particle size (3-5 microns) and a narrow PSD. For impinging jet crystallization, industrial operation is described by Midler et al. (1994), with vtuiants by Lindrud et al. (2001) (impinging jet crystallization with sonication) and by Am Ende et al. (2003) (specific reference to reactive crystallization). Laboratory studies are reported by Mahajan and Kirwan (1996), Benet et al. (1999), Condon (2001), and Hacherl (Condon) (2003), Johnson (2003) and Johnson and Prud homme (2003) report on the use of impinging jets to produce nanoparticles stabilized by block copolymers. 

Disposable IR cards with a thin polymer film window are available for the qualitative analysis of liquids. (These cards were originally manufactured by 3M , but are now available from International Crystal Laboratories, Garfield, NJ, and other suppliers.) Two polymer substrates are available polytetrafluoroethylene for the 4000-1300 wavenumber region and polyethylene for the lower wavenumber region. The absorption spectra for these two materials are displayed in Fig. 4.19(b) and (c). A thin film can be deposited onto the polymer window by evaporation from solution or by smearing the liquid onto the polymer. A major advantage of these cards is that the polymer films do not dissolve in water therefore... 

PROFESSOR YUE ZHAO Polymer and Liquid Crystal Laboratory, Department of Chemistry, University of Sherbrooke, Quebec, Canada... 

LiCryL, INFM Regional Liquid Crystal Laboratory Physics Department University of Calabria via Pietro Bucci - Cubo 31C 87036 Rende (CS), Italy barberiSfis.unical.it... 

Despite the large volumetric differences in this example (100 1), the vessel diameter differences are really quite small (5 1). Therefore, since the vessel diameter is an important parameter in a crystallizer, laboratory-scale crystallization operations may not be vastly different from those in pilot-plant work, and pilot scale from industrial scale. 

Hydrate is a term related to a substance that contains water of crystallization. In inorganic chemistry, hydrates refer to inorganic salts that have water molecules crystallized with salt compounds in a definite ratio. An example is copper sulfate, which turns from gray-white (anhydrous form) to blue (pentahydrate) uptm hydration. Such hydration can easily be carried out by dissolving anhydrous (water free) copper sulfate in water and crystallizing. Laboratory research reveals that five water molecules occur in a copper sulfate crystal unit, and four of them are attached to the copper ion by coordination bonds, whereas the fifth is supposed to be held to sulfate... 

X-ray diffraction apparatus is often available in a liquid crystal laboratory whereas neutrons are only available at central facilities such as the Institut Laue Lange-vin (ILL), Grenoble, or the ISIS Neutron Source, Oxfordshire. 

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