This work presents a novel method for the accurate determining trans- and cis-resveratrol (3,5,4'-trihydroxystilbene) by nonaqueous capillary electrophoresis/fluorescence spectroscopy at 77 K. The proposed method permits not only the separation of resveratrol isomers, but also ensures that on-line spectra are readily distinguishable and unambiguously assigned. The experimental results also indi...

We examined the stability of emulsions of oil in several nonaqueous polar liquids using commercially available nonionic surfactants. Stable nonaqueous emulsions were only obtained with formamide and dimethylsulfoxide. Hydrogen bonding, and not polarity, appears to be the important factor determining the emulsifying power of a solvent. Ostwald ripening plays a much more important role in the sta...

Metal oxide nanoparticles can be fabricated under high control via nonaqueous sol-gel synthesis. This route has been shown to lead to highly crystalline, uniform nanostructures, which explains the high and growing interest it is receiving. The underlying mechanisms are, however, so far only rudimentarily understood on a molecular scale. Here, we applied in situ FTIR spectroscopy and other techn...

answer. However, there is no reason why reactions cannot be carried out on such devices. Since it does not require the investment of a large chemical plant, the reactions can be performed where required, thus reducing the need to transport hazardous chemicals across countries. Since many reactors can be constructed on a single chip, and many chips located in the same area, it is evident that th...

Computational simulations of two-phase flow in porous media are used to investigate the feasibility of replacing a porous medium containing heterogeneities with an equivalent homogeneous medium. Simulations are performed for the case of infiltration of a dense nonaqueous phase liquid (DNAPL) in a water-saturated, heterogeneous porous medium. For two specific porous media, with periodic and rath...

The possibility and usefulness of sinple liquid models is reported. The importance of van der Waals forces for liquid water and aqueous solutions is discussed and compared with the solubility of water in nonpolar solvents and as well as of nonpolar solvents in water. Both systems could be understood as equilibrium of few water monomers. The network of H-bonded water molecules seems to be less i...

varying degrees of water solubility. Some additives (e.g., methyl tertiary-butyl ether and alcohols) are highly soluble. Other components (e.g., benzene, toluene, ethylbenzene, and xylenes) are slightly soluble. Many components (e.g., ndodecane and n-heptane) have relatively low water solubility under ideal conditions. Physical and chemical properties which affect transport and fate of selected...

Research on nonaqueous microemulsions containing ionic liquids as polar and/or apolar phase, respectively, is growing at a fast rate. One key property of ionic liquids that highlights their potential and their diversification compared to water is their wide liquid temperature range. In this emerging-area review article we survey recent developments in the field of nonaqueous micellar solutions ...

The Regional Superfund Ground Water Forum is a group of EPA professionals representing EPA’s Regional Superfund Offices, committed to the identification and the resolution of ground water issues impacting the remediation of Superfund sites. The Forum is supported by and advises the Superfund Technical Support Project. Dense nonaqueous phase liquids is an issue identified by the Forum as a conce...

Nicotinamide nucleotide coenzymes were estimated spectrophotometrically in noninfected barley leaves and leaves infected with Erysiphe graminis var hordei (powdery mildew). Amounts of NADH, NADP(+) and NADPH were not altered by infection. In contrast, the NAD(+) content rose sharply and at 144 hours was 100% greater than in noninfected leaves. The respiratory rate was increased in infected leav...