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The investigation of the degradation of two commercially available dyes (Remazol Turquoise Blue and Everzol Turquoise Blue) by the lignin-degrading fungus Phanerochaete chrysosporium and comparison with that of a phthalocyanine whose structure is known (Heligon Blue) are presented. Atomic absorption showed a large release of copper from the biomass at day 7. Polarography served to speciate the copper present in the supernatant. Day 5 sees the complete disappearance of the main dye peak with the release of free copper into the supernatant. Day 7 sees a large increase in the free copper signal with two other electroactive species also present in the supernatant, all of which are seen to decrease at day 8. Visible spectroscopy shows that the main decolourization takes place between day 4 and day 6, with complete decolourization occurring at day 7. HPLC analysis again confirms the above results, with possible degradation products detected at 254 nm occurring at 3.621 and 4.170 min at day 7 which may well correlate with those found in polarographic analysis at –1050 and –1150 mV. Day 7 also sees a large increase in a peak at 2.744 min.

Monolithic columns have attracted much attention as a novel platform for high throughput analysis, but there is little information about the fluid profile in the flow channels. In this paper, we presented our approach for the fluid simulation in column chromatography by the lattice Boltzmann method (LBM). To simulate the monolithic column system, the calculation domain was modeled by the 3D channel flow through sphere obstacles. Several types of porous structure were used, with uniform and nonuniform pores. Based on the simulations results, we discussed fluid flow and pressure variation for the optimization of the suitable structure for HPLC system.

Medicinal herbs have a long history of use in the practice of traditional Chinese medicine and a substantial body of evidence has, over recent decades, demonstrated a range of important pharmacological properties. Western biomedical researchers are examining not only the efficacy of the traditional herbal products but, through the use of a range of bioassays and analytical techniques, are developing improved methods to isolate and characterize active components. This review briefly describes the different extraction methodologies used in the preparation of herbal extracts and reviews the utility of chromatography-mass spectrometry for the analysis of their active components. In particular, applications of gas or liquid chromatography with mass spectrometry for the isolation and characterization of active components of ginseng are critically assessed. The analysis of toxic substances from herb extracts with mass spectrometric techniques is also discussed along with the potential for mass spectrometric methods to investigate the proteomics of herbal extracts.

We used carbon soot produced by electrical arc method. Fullerenes, mainly C₆₀ and C₇₀, were Soxhlet extracted from collected soot with chlorobenzene, by modified procedure yielding 5.8% of the extract. Chlorobenzene fullerenes extract was then separated on an active alumina column, modifying the existing methods, by elution with hexane and xylene/hexanes mixtures in determined ratios and orders. Buckminsterfullerene C₆₀ was identified in the first purified fraction using EI mass spectrometry, IR and UV/vis methods. The second and the third purified fraction, carbon soot and chlorobenzene soot extract were characterized by IR and UV/vis methods. Identifications of fullerenes in purified and unpurified forms were analyzed and compared.

A newly developed computational fluid dynamics method for simulating chromatographic adsorption is presented. This well-validated software package takes adsorption reactions as well as internal porosity into account to explain differences caused by the design and flow regime. Focusing on the band broadening in perfectly ordered 2D chromatographic columns, it is found that the method used for forcing the fluid through the column has a significant influence. Electro-osmosis-driven (ED) flows have a slight advantage (i.e. produce less band broadening) over pressure-driven (PD) flows. This is explained by the way the flow passes through a tortuous pore structure with changing pore size. Furthermore, this behavior does not change when the shape of the pillars is changed. Only for hexagon-like shapes is there a slight gain in performance for ED flows based on a bigger recuperation mechanism typical of ED flows in undulating pore spaces. When concentrating on the effect of the pillar, a better performance is obtained for more elongated shapes compared to more compact shapes like cylinders, as they pack in a more uniform pore space. It is also observed that the uniformity of the fluid field is the most important factor when comparing different shapes or systems. Heterogeneity in the velocity field inevitably leads to an increase of the band broadening.

More and more biomolecules are being produced by the biotechnology industry for applications ranging from medicine and food to engineering materials. Liquid chromatography plays a center-stage role in a typical downstream process producing biomolecules such as recombinant proteins. Rigid gigaporous media are porous particles possessing large transecting through-pores with a pore-to-particle diameter ratio of d_pore/d_particle > 0.01. They allow convective flow in the large through-pores, while the smaller diffusion-pores (typically several hundred angstroms in size) supply the needed surface areas. Because of the transecting gigapores, a portion of the mobile phase flows through the pores in addition to fluid flow in the interstitial spaces between the particles in a packed-bed column. This considerably lowers the operating column pressure drop. This lower pressure drop makes axial-direction scale-up of chromatographic columns possible to avoid pancake columns that invariably degrade separation resolution. The large gigapores also make the binding sites on the diffusion pore surfaces more accessible, thus increasing the loading capacity of large protein molecules that can be hindered sterically if only diffusion pores are present. This work discusses the development of rigid gigaporous media and their potential impact on the design of multi-stage downstream process from the angle of multi-scale analysis.

Singular shocks were first devised over 20 years ago as a tool to resolve some otherwise intractable Riemann problems for hyperbolic conservation laws. Although they appeared at first to be merely a mathematical curiosity, new applications suggest that they may have some greater significance. In this paper, I recount the story of their discovery, which owes much to Michelle Schatzmann, describe some of their old and new appearances, and suggest intriguing possible connections with change of type in conservation law systems.