Hydro-focusing

Sundararajan N, Pio M, Lee L, Berlin A (2004) Three-dimensional hydrodynamic focusing in polydimethylsiloxane (PDMS) microchannels. J Microelectromech Syst 13(4) 559-567 Yang R, Feeback D, Wang W (2005) Microfabrication and test of a three-dimensional polymer hydro-focusing unit for flow cytometry applications. Sens Actuators A Phys 118(2) 259-267... 

The ocean plays a central role in the hydro-spheric cycling of sulfur since the major reservoirs of sulfur on the Earth s surface are related to various oceanic depositional processes. In this section we consider the reservoirs and the fluxes focusing on the cycling of sulfur through this oceanic node. 

Abstract This chapter focuses on carbon monoxide as a reagent in M-NHC catalysed reactions. The most important and popular of these reactions is hydro-formylation. Unfortunately, uncertainty exists as to the identity of the active catalyst and whether the NHC is bound to the catalyst in a number of the reported reactions. Mixed bidentate NHC complexes and cobalt-based complexes provide for better stability of the catalyst. Catalysts used for hydroaminomethylation and carbonyla-tion reactions show promise to rival traditional phosphine-based catalysts. Reports of decarbonylation are scarce, but the potential strength of the M-NHC bond is conducive to the harsh conditions required. This report will highlight, where appropriate, the potential benefits of exchanging traditional phosphorous ligands with iV-heterocyclic carbenes as well as cases where the role of the NHC might need re-evaluation. A review by the author on this topic has recently appeared [1]. 

The starting point for much of the work described in this article is the idea that quinone methides (QMs) are the electrophilic species that are generated from ortho-hydro-xybenzyl halides during the relatively selective modification of tryptophan residues in proteins. Therefore, a series of suicide substrates (a subtype of mechanism-based inhibitors) that produce quinone or quinonimine methides (QIMs) have been designed to inhibit enzymes. The concept of mechanism-based inhibitors was very appealing and has been widely applied. The present review will be focused on the inhibition of mammalian serine proteases and bacterial serine (3-lactamases by suicide inhibitors. These very different classes of enzymes have however an analogous step in their catalytic mechanism, the formation of an acyl-enzyme intermediate. Several studies have examined the possible use of quinone or quinonimine methides as the latent... 

In outline of what follows we will begin by brief reference to previous work on coal liquefaction. The present approach will then be motivated from considerations of coal structure and hydro-gen-donor activity. A theoretical section follows in the form of a pericyclic hypothesis for the coal liquefaction mechanism, with focus on the hydrogen transfer step. Experiments suggested by the theory are then discussed, with presentation of preliminary results for hydrogen transfer among model substrates as well as for the liquefaction of an Illinois No. 6 coal to hexane-, benzene-, and pyridine-solubles by selected hydrogen donors. 

The C/O amide bond replacements include methyleneoxy, 1-hydroxyethylene, 2-hydro-xyethylene, 1,2-dihydroxyethylene, 1-oxoethylene, and epoxide isosteres. This chapter focuses on the synthetic methods of dipeptide building blocks containing these isosteres. 

In this paper, the focus is on the development of a poromechanics model which addresses the chemical effects within the framework of the anisotropic porothermoelastic model [2], The resulting model, termed as porochemo-thermoelastic, accounts for fully coupled chemo-thermo-hydro-mechanical response of a chemically active formation saturated with a pore fluid comprising of two species under non-isothermal conditions. The numerical example presented demonstrates the thermo-chemical effect on the stress and pore pres-... 

In a cross-flow configuration, one stream with one fluid enters from the left and two streams carrying the same other fluid are fed from above and below [112]. The latter have much larger flow rates as the first stream so that this layer is hydro-dynamically compressed when all three streams enter the outlet channel on the right side of the cross. The channel which carries the stream to be focused narrows to a kind of nozzle when approaching the T-junchon... 

In the absence of EOF (e.g., in non-cross-linked acrylamide-coated capillaries), the focused zones should be mobilized either chemically or with hydro-dynamic flow. During this mobilization, maintenance of the electric field serves as a stabilizer to prevent zone broadening. A common name for such a setup is two-step capillary isoelectric focusing. 

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