Micro-dispersion

These devices have gas and liquid streams which do not merge, i.e. are not fed into each other. Rather, by use of separate ports both phases are passed in their own encasing, e.g. their own micro channel. Thereby, dispersion of the phases is prevented and only one large specific interface is created for mass transfer (different from dispersive micro devices, see, e.g.. Section 5.1.2). The separate guidance of the phases allows to heat the phases separately, usually from the side most distant from the gas/liquid interface. 

Bronk, H., Rohrs, S., Bjeoumikhov, N., et al. (2001). ArtTAX- a new mobile spectrometer for energy-dispersive micro X-ray fluorescence spectrometry on art and archaeological objects. Fresenius Journal of Analytical Chemistry 371 307-316. 

The IBW of a standard system can be reduced to 30-40 jL by using shorter lengths of 0.005-0.007" i.d. tubing and a semi-micro flow cell (2-3 tL).i° Further reduction might involve a low dispersion micro-injector or a redesign of the autosampler. Table 4 summarizes the typical IBW and other instrumental requirements of various column types from conventional (4.6 mm), Fast TC, minibore (3 mm), narrowbore (2 mm) and microbore (1mm) to micro TC (<0.5mm) columns. Note that the dispersion... 

The entire region enclosed by the outer dome represents immiscibility. The inner dome is known as the spinodal. The outer dome is known as the binodal. In the region of composition between the binodal and spinodal lines, phase separation occurs by the nucleation and growth mechanism and leads to the formation of dispersed micro-spherical glass particles in the matrix (see also Shelby, 1997). Spinodal decomposition which takes place inside the dotted region is a special type of phase separation. In order to understand this, consider two materials A and B, melts of which... 

Further reduction of IBW might involve the replacement of the existing injector with a low-dispersion micro-injector or an autosampler designed for micro LC. 

Uses Detergent, wetting agent, solubilizer, dispersant, micro-emulsifier for laundry prods., hard surf, cleaners, industrial specialties, solid air fresheners, toilet blocks, pesticides/herbicides agric. adjuvant for water disp. systems dispersant for aq. coatings and inks Properties Clear liq. oil-sol. pH 2.5 (10% aq.) surf. tens. 34.5 dynes/cm (0.01%) Ross-Miles foam 105 mm (0.1%, 40 C, initial) anionic 90 3% solids... 

Takatori and his collaborators in Toyota Research Center were one of the first who developed and systematically studied the emulsion combustion method (ECM) [3]. This method is basically a combination of the microemulsion wet chemistry and the flame spray pyrolysis methods. In ECM, an aqueous solution of a metal salt is mixed with a fuel such as kerosene and a small amount of an emulsifier or surfactant to obtain a water-in-oil (W/O) type of emulsion. Using a spray nozzle, the solution is then atomized to produce a spray. The size of the mother emulsion droplets depends on the atomizer type and the atomization conditimis, and is on the order of 10 pm for air-assist nozzles. The size of the dispersed micro-solution droplets depends on the string process and surfactant, and is about 1 pm [3]. Figure 40.1 shows a schematic diagram of the ECM. 

The process of particle formation from the micro-solution droplets dispersed in emulsion droplets has similarities to that of the spray pyrolysis, although under certain conditions (high temperatures) it could become totally different. In the ECM, burning of the fuel fraction of the emulsion droplet works as a heat source for drying of the dispersed micro-solution droplets. As a result, provided that the... 

In calculation of the total density of an emulsion droplet, the presence of solute may be neglected, if the concentration of micro-solution droplets is low. It is rational to assume that the temperature of the dispersed micro-solution droplets... 

C. Sirotti, I. Colombo, and M. Grassi, Modelling of drug-release from poly-disperse micro-encapsulated spherical particles,/owma/ of Microencapsulation, 19 (5), 603-614,2002. 

The combination of XRF with electrophoresis can constitute a quasi-on-line coupling technique. Great efforts have been made to develop on-line analysis techniques with XRF. Mann et reported a technique of on-line SRXRF detection of metal ions, such as Fe, Co, Cu, and Zn, in their high binding-constant complexes for capillary electrophoresis (CE) separation. An X-ray transparent polymer coupling is used to create a window for the on-line X-ray detection. In contrast to ICP-MS, this detection technique is not limited by sample or the buffer volatility or atomization efficiency. Simultaneous XRF and UV absorbance detection can be used to provide on-line determination of metal/chelate ratios. A bench-top energy-dispersive micro X-ray fluorescence system was also combined with the CE apparatus constructed by a thin-walled fused-silica capillary for elemental analysis of the species containing Fe, Co, and Cu, for example. This coupled technique used for metalloprotein speciation analysis can avoid the compromise between optimal separation and sensitive detection, which must be taken into account in the HPLC-ICP-MS procedure. In addition, this detection scheme is non-destructive, so the separated material can be recovered for additional characterization. 

Tol RT, Mathot VBF, Groeninckx G. Confined crystallization phenomena in immiscible polymer blends with dispersed micro- and nanometer sized PA6 droplets, part 2 reactively compatibilized PS/PA6 and (PPE/PS)/PA6 blends. Polymer 2005 46 383-96. 

Tol R, Mathot V, Groeninckx G. Confined crystallization phenomena in immiscihle polymer blends with dispersed micro- and nanometer sized PA6 droplets, part 3 crystallization kinetics and crystallinity of micro- and nanometer sized PA6 droplets crystallizing at high supercoolings. Polymer 2005 46(9) 2955-65. Tol R, Mathot V, Groeninckx G. Confined crystallization phenomena in immiscihle polymer blends with dispersed micro- and nanometer sized PA6 droplets, part 1 uncompatibilized PS/PA6, (PPE/PS)/PA6 and PPE/PA6 blends. Polymer 2005 46(2) 369-82. 

Employing the field emission gun scanning electron microscopy (FEG-SEM) and TEM to study the morphology of the epoxy reinforced with polystyrene-p-polybutadiene-p-poly(methyl methacrylate) block copolymer (SBM), the nanostructured epoxy matrix with disperse micro-scale phase was revealed. Enhanced flexural properties, which were dependent on the composition of blend was obtained. 

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