Current topics in physical and nanoparticle electrochemistry

Electron transfer to a redox couple across an insulating layer is greatly enhanced by attached nanoparticles which act, in this case, as a tunnelling “short circuit” element for the two-step ET reaction.

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Current topics in smectic liquid crystal research.

Interest in the smectic liquid-crystalline state of matter received a substantial boost with the discovery by Meyer in the mid-1970s that a chiral smectic C (SmC*) phase exhibits a spontaneous electric polarization, and with the subsequent demonstration by Clark and Lagerwall of the surface-stabilized SmC* ferroelectric liquid crystal at the beginning of the 1980s. Since then, chiral smectic phases and their plethora of polar effects have dominated the research in this field, which today has reached a mature state where the first commercial microdisplay applications are now shipping in millions-per-year quantities. In this Review we discuss some of the topics of highest interest in current smectic liquid crystal research, and address application-relevant research (de Vries-type tilting transitions without defect generation and high-tilt antiferroelectric liquid crystals with perfect dark state) as well as more curiosity-driven research (the nature and origin of the chiral smectic C subphases and their intermediate frustrated states between ferro- and antiferroelectricity).     

Drugs and related topics

Drugs is a topic that was certainly an issue of discussion at this year's annual meeting. This Committee had the responsibility of organizing a half day symposium on "Pharmaceutical Authenticity and Safety" that took place September 12, 2005. This symposium aims at improving the critical points in the analytical pharmaceutical field related to traceability assessment, use of certified reference materials (CRMs), and proficiency testing implementation to get the highest quality of the obtained results. Recognized experts presented these topics. Also, other complementary subjects, such as the application of advanced analytical technologies to reach the authenticity and safety of the pharmaceutical drugs and drug products, their microbiological quality assessment, without disregarding an important topic such as sampling, was presented and discussed. The talks that were presented are the following: "Proficiency Testing as a Need in the Pharmaceutical Field," Arlene Fox (AOAC INTERNATIONAL, Gaithersburg, MD); "Implementation of Traceability in the Pharmaceutical Laboratory," Thomas Layloff, (Management Sciences for Health, Arlington, VA); "Harmonized Characteristics of Certified Reference Materials According to ISO Guides-Attractive also for Pharmaceutical Analysis," Hendrik Emons (Reference Materials, Unit Institute for Reference Materials and Measurements (IRMM), Joint Research Centre European Commission, (Geel, Belgium); "Importance of LC/MS/MS for the Fingerprinting of Pharmaceutical Drugs," Paul A. Steinberg, (Thermo Electron Corp., Woodstock, GA); "Process Analytical Technology (PAT) as a Way for Better Manufacturing and Quality Assurance," John F. Kauffman (Division of Pharmaceutical Analysis, U.S. Food and Drug Administration (St. Louis, MO); "Stability Testing for the Safety Assessment of Pharmaceuticals," Marta Vidal (Boeringher Ingelheim Argentina, Buenos Aires, Argentina); "Validation of Microbiological Methods for Sterile and Nonsterile Pharmaceutical Products," Michael Brodsky (Brodsky Consultants, Thornhill, ON, Canada); "The Relationship Between Pharmacopoeial Reference Standards and ISO REMCO Initiatives and Guides," Ronald G. Manning (United States Pharmacopoeia, Rockville, MD).     

DFT investigation on some nitrogen-doped fullerenes with more antiradical and antioxidant activities than C60

Structural Chemistry - Although fullerene C60 is a strong scavenger for alkyl radicals, it is insusceptible toward peroxyl radicals. Substitution of carbon atoms in the fullerene cage by...     

Letter: some more aspects of formation and stability of the protonated serine octamer cluster

The formation of protonated serine octamer clusters from homochiral and heterochiral monomer solutions was investigated. The well-established preference for homochiral cluster formation was found to originate from collision-induced dissociation of the less stable ion population B prior to reaching the mass spectrometer's analyzer cell. In addition, collision-induced dissociation experiments were undertaken to investigate the relative stabilities of populations A and B and infrared multi-photon dissociation experiments addressed the relative stabilities of the protonated serine octamer cluster and its metaclusters. Isotopically-labeled serine was used throughout the experiments.     

Polarographic reduction of some potential antidiabetic compounds with more than one reduction site

The polarographic reduction of a number of N'-guanylarylazopyrazole nitrates has been studied over a range of concentration and pH values. The effect of substituent groups on the value of the half wave potential has been determined.     

Review: Current studies on some physical properties of ionic liquids

As a novel substituting solvent for organic solvents, low-temperature ionic liquids have attracted much attention as good media in organic synthesis and other chemical processes. Better understanding of physical properties of ionic liquids are very helpful in exploring reaction mechanisms and controlling reaction outputs. This review summarises current studies on several physical properties (melting point, vapor pressure and stability, polarity, miscibility, density, viscosity) that are important for organic reactions.