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A new instrument for monitoring atmospheric C[O.sub.2] has been developed based on the measurement of the speed of sound in air. The instrument uses a selective scrubber to yield highly precise and accurate measurements of C[O.sub.2] mixing ratios at ambient concentrations. The instrument has a precision of 0.3 ppmv (1[sigma]) with a signal that is independent of pressure and requires a flow rate of only 30 mL/min. Laboratory measurements of atmospheric C[O.sub.2] showed excellent agreement with values obtained by nondispersive infrared absorption. The instrument has the advantage of collecting continuous, high-precision data every 25 s and can be modified for vertical profiling studies using kites, balloons, or light aircraft for the purpose of measuring landscape-scale fluxes. 10.1021/ac101365p

A new portable instrument has been developed that offers rapid detection of ozone at the parts per billion (ppb) level for personal exposure monitoring. The personal ozone monitor is based on the EPA Federal Reference Method of UV absorbance and has the advantage of being small (10 cm x 7.6 cm x 3.8 cm), lightweight (0.3 kg), low power (2.9 W), and battery-operated. The instrument can be worn by an individual during normal daily activities because it is unaffected by humidity, physical orientation, temperature, and vibration. In order to eliminate any significant interference from water vapor, Nation tubing was installed before the detection cell, and the optical path was lined with quartz. A precision of 1.5 parts per billion by volume (ppbv) and limit of detection of 4.5 ppbv (S/N = 3) was demonstrated with the instrument making measurements every 10 s. 10.1021/ac1013578

A synthetic strategy is described for the preparation of well-defined [epsilon]-caprolactone oligomers up to the 64-mer by using an iterative divergent-convergent approach. The results have shown a distinct structure/property relationship with a close correlation between the number of repeat units and physical properties.

Numerous studies and researches are conducted to analyze several molecular systems, like the butadiyne-linked porphyrin oligomers and molecular wires, which can efficiently mediate electrons in a controlled manner over nanometer distances. The analysis reveals that such oligomers exhibit extremely fast rates of long-range charge recombination and very weak distance dependence and hence can be widely used as molecular wires.

The hydrogen storage capacity of binary THF-[H.sub.2] clathrate hydrate is determined as a function of formation pressure, THF composition and time. The maximum amount of hydrogen stored in the binary hydrate is about 1.0 wt % at moderate pressure and is also found to be independent of the initial THF concentration.

A study on a new methodology for the preparation of well-defined core-shell nanoparticles was developed, based on the employment of a multifunctional crosslinker to coincidently stabilize supramolecular polymer assemblies and imbed into the shell unique chemical functionalities. It is concluded that this type of nanoparticle crosslinking and subsequent functionalization provides a facile route for the future attachment of biologically important molecules.

Mn(II)9 self-assembled [3X 3] grid complexes were successfully oxidized chemically and electrochemically. Structures were reported for [Mn9(2poap-2H)6](NO3)6(super .)14H2O (1), [Mn9(2poap-2H)6](CIO4)10(super .)10H2O (3), and [Mn9-(Cl2poap-2H)6](ClO4)9.14H2O.3CH3CN (10).

Seeding and autocatalytic reduction of platinum salts in aqueous surfactant solution using ascorbic acid as the reductant leads to dendritic metal nanostructures. Synthetic control over the morphology of these Nan dendrites, nanosheets and nanostructured foams is realized by using a tin-porphyrin photocatalyst to conveniently and effectively produce a large initial population of catalytic growth centers.

The bleomycins (BLMs) are structurally related glycopeptide antibiotics isolated from streptomyces vetricillus that mediate the sequence-selective oxidative damage of DNA and RNA. Deglycoblemycin, which lacks the carbohydrate moiety cleaves DNA analogously to bleomycin itself and is used for analyzing the functional domains of bleomycin.

A new approach in the manipulation of the size and chemistry of nanoscopic characteristics using contact molding and living free radical polymerization is presented. A focus is also laid on creating templates for pattern replication and the development of process steps for transferring images into molecular electronics applications.

Simple models of chemical phenomenon could be useful insights and predictive power. These models were parameterized using data on model systems that are chosen to allow the effects of interest to be isolated.

The view that the large red shifts seen in the UV-visible adsorption bands of peripherally crowded nonplanar porphyrins are the result of nonplanar deformations of the macrocycle is challenged by the suggestion that the red shifts arise from substituent-induced changes in the macrocycle bond length and bond angles. Results of studies suggest that UV-visible band shifts of tetrapyrroles in proteins are potentially useful indicators of changes in nonplanarity provided other structural and electronic factors can be eliminated.

Research has been conducted on nickel(II) porphyrins. The electrochemistry of these compounds has been investigated in the effort to understand the effect of structural and electronic factors on electron-transfer processes in porphyrins, and the details are reported.

A study was conducted to demonstrate a viable synthetic strategy for the controlled intramolecular collapse of linear polymer chains to produce single-molecule nanoparticles. By using a continuous addition strategy in conjuction with thermally activated benzocyclobutene-coupling chemistry, intermolecular cross-linking could be effectively eliminated at high concentration (0.1 M), which makes it a practical technique for large-scale synthesis of well-defined nanoparticles.

The proximal carboxyl terminus of the angiotensin II receptor is associated with the cell membrane by tethering through a high-affinity, anioninc phospholipid that enhances the amphipathic helicity of the terminus, indicating that this region of the terminus is sensitive to hydrophobic environment.

Research has been conducted on the macromolecules. The effect of the macromolecule architecture on the polymeric materials' physical properties has been investigated via the analysis of poly(benzyl ether) dendrons and their linear analogues and the details are presented.

Research has been conducted on the bleomycin group of antitumor antibiotics. The mechanism of bleomycin and DNA interaction has been investigated via the synthesis of the trithazole-containing deglycoblemycin analogue and the ability of this analogue to relax supercoiled DNA and to cleave linear duplex DNA has been studied.

The authors review the publications on the radical polymerization. The topics of interest include nitroxide-mediated living free radical polymerization, strategies for polymeric structure and macromolecular architecture control and the design of nitroxides with improved performance.

Research describes the synthesis of unique, homoleptic, trigonal bipyramidal cluster complexes by a strict self-assembly process involving the ligands poap and p3oap and the proper metal perchlorate salt.

It has been possible to use a macromonomer technique to synthesize and characterize complex dendritic, rigid rod poly-2,7-fluorene homopolymers and copolymers. Self-encapsulation in a dendritic matrix produced site isolation of the fluorescent poly-2,7-fluorene backbone.

Research has been conducted on the reaction of porphyrins with osmium tetraoxide. The effect of the electron-donating and electron-withdrawing substituents on these porphyrins has been investigated.

Research has been conducted on the Yokoyama's indolyl fulgide. The synthetic route to this fulgide, techniques modifications and the methodology development are reported