A decade of capillary electrophoresis

Since the introduction of the first commercial capillary electrophoresis (CE) instrument a decade ago, CE applications have become widespread. Today, CE is a versatile analytical technique which is successfully used for the separation of small ions, neutral molecules, and large biomolecules and for the study of physicochemical parameters. It is being utilized in widely different fields, such as analytical chemistry, forensic chemistry, clinical chemistry, organic chemistry, natural products, pharmaceutical industry, chiral separations, molecular biology, and others. It is not only used as a separation technique but to answer physicochemical questions. In this review, we will discuss different modes of CE such as capillary zone electrophoresis, micellar electrokinetic chromatography, capillary gel electrophoresis, capillary isoelectric focusing, and capillary electrochromatography, and will comment on the future direction of CE, including array capillary electrophoresis and array microchip separations.     

Evaluating the third and fourth derivatives of spectral data

The problem of differentiating spectral data to yield the third and fourth derivatives is converted into one of solving an integral equation of the first kind. This equation is solved by Tikhonov regularization. The method of General Cross Validation is used to guide the choice of the regularization parameter that keeps noise amplification under control. The performance of this route to third and fourth derivative spectra is demonstrated by applying it to a number of published spectra. A computational problem associated with General Cross Validation has been identified.     

An industrial view of polymer science in the next decade

Nearly thirty years go when I left graduate school at the University of Michigan and joined General Electric's Research Laboratory, I was impressed by the diversity and vitality of the polymer industry worldwide and by the opportunities for polymer science and technology to make that industry even larger, stronger and more diverse. Most of all, I was excited at the prospect of being a contributor to that future. I'm still excited to be a part of that industry and especially pleased at this conference to be in the presence of the many outstanding individuals who have created today's polymer science and technology, and to be in the presence of those who will create tomorrow's.     

Progress toward the polymerization of a fourth generation dendritic macromonomer

The g‐scale synthesis of the fourth generation dendronized monomer 3 d and its Suzuki oligomerization are reported. The monomer synthesis uses the fact that the addition of two G‐3 fragments to aryldibromide 3 c which already contains one branching unit is more practical than an alternative approach by which a G‐4 dendron is added to a respective compound. The Suzuki cross‐coupling of 3 d gives oligomeric material 5 , a fraction of which with a molecular weight of M_n = 170 000 is obtained by preparative gel permeation chromatography. This finding shows that the Suzuki cross‐coupling reaction can cope with considerable steric loading of coupling components which opens up new perspectives for its applicability both in organic and polymer chemistry.     

Supramolecular gel chemistry: developments over the last decade

This highlight gives a brief flavour of the development of gels derived from low molecular weight gelators broadly in the first decade of the 2000's. A particular theme is the emergence of switchable gels and increasing hi-tech niche application areas. Control and exploitation of supramolecular gels forms a huge part of the grand challenge of directed assembly of extended structures with targeted properties.     

Small molecule microarrays: the first decade and beyond

The turn of the century witnessed the development of small molecule, protein, cell and tissue microarrays, heralding a new era of discovery-driven research using a host of different chemical libraries, biomolecules and tissue types. This highlight takes stock of this first decade of small molecule microarrays (SMMs) and describes how the technology has matured into a robust screening platform. We also highlight the many interesting and unique applications appearing using small molecule microarrays, in order to project forward to possible areas in which SMMs could contribute further to over the next five to ten years.     

Resonance coupling in the fourth OH-stretching overtone spectrum of formic acid

The room-temperature vibrational overtone spectra of the formic acid isotopomers HCOOH and DCOOH have been recorded in the third and fourth OH-stretching overtone regions with intracavity laser photoacoustic spectroscopy. Resonance coupling between the OH- and CH-stretching vibrations in HCOOH is clearly identified in the fourth overtone region. This is an example of strong coupling across bonds. In the third overtone region, no resonance is observed. Vibrational energies and intensities of the OH- and CH-stretching overtones and combination bands have been calculated with an anharmonic oscillator local mode model. The pure OH-stretching bright state carries almost all the intensity prior to resonance coupling.     

HPLC of biological macromolecules: The first decade

Summary During the past decade, HPLC has developed into a powerful new technique for the analysis of complex mixtures of biological macromolecules. Through the use of microparticulate supports of vastly improved mechanican strength, superior stationary phase chemistry, and advanced instrumentation, it is now possible to separate biological macromolecules more than 10 times faster and with greater resolution than in the classical SEC, IEC, HIC, bioaffinity, and hydroxyapetite chromatography columns. Additionally, the introduction of new separation modes such as RPC and metal chelate make it possible to carry out separations that were not possible with the classical gel-type media. It is anticipated that 1) expanded use of non-porous media, 2) development of new stationary phases for carbohydrates, 3) greater throughput and resolution in preparative separations, and 4) better understanding of retention mechanisms are a few of the areas of macromolecular separations in which advances can be expected in the next few years.     

Fluorine-containing agrochemicals in the last decade and approaches for fluorine incorporation

In this review, the methodologies for fluorine incorporation of 40 fluorine-containing agrochemicals that received an international standardization organization(ISO) name during the last decade are described.The predominant approach for fluorine introduction of these agrochemicals is to use a fluorine-containing building block. Here we present how the fluorine-containing building blocks are introduced into these agrochemicals. The synthetic methods of fluorine-containing building blocks that are...     

Dihydroagarofurans: the fourth isomer isolated from Cedrelopsis grevei bark oil

4-Epi-cis-dihydroagarofuran was isolated from the bark oil of Cedrelopsis grevei and its structure was elucidated by 1D and 2D-NMR spectroscopy.     

ELDONET--a decade of monitoring solar radiation on five continents

The European light dosimeter network (ELDONET) comprises more than 40 stations in 24 countries on 5 continents. The present report compares solar radiation data in the photosynthetic active radiation, UV-A (315-400 nm) and UV-B (280-315 nm) wavelength ranges for 17 stations at different latitudes on the northern and southern hemispheres for up to 10 years of monitoring. While the maximal irradiances on clear days follow a latitudinal gradient due to the cosine dependence on the solar angle, the total doses strongly depend on the local climate and atmospheric conditions as well as the day-length distribution over the year. UV-B irradiances and doses are strongly influenced by the total column ozone, which is recorded for all covered stations.     

The fourth virial coefficient of a nonadditive hard-disc mixture

The fourth virial coefficient of symmetric nonadditive hard-disc mixtures is calculated over a wide range of nonadditivity. The irreducible cluster integrals were evaluated numerically using a standard Monte Carlo method. The coexistence line relative to the fluid-fluid phase transition, calculated through two equations of state built using the new virial coefficients, is compared with some numerical simulation results.