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As a first step towards the greening of instructional laboratories, we present a new greener version of a laboratory procedure designed to measure colligative properties. The greener procedure substitutes the nontoxic, noncarcinogenic compounds stearic, myristic, lauric, and palmitic acids for the less benign aromatic compounds p-dichlorobenzene, benzil, biphenyl, naphthalene, and nitrotoluene. Achieving educational goals without the concomitant generation of chlorinated and aromatic wastes is shown here to be both possible and practical. Furthermore, utilization of the benign fatty acid waste stream for other purposes, such as making soap, wax, or biodiesel, allows this laboratory to approach the zero waste benchmark.

Solid state x-ray crystallographic characterization and multinuclear paramagnetic NMR spectra of manganese(III) complexes were established. The binding of axial ligands to Mn(III) was observable by nuclear magnetic resonance. Results obtained indicated that a hydrogen bond of the water molecule bound to the F atom of the PF(sub 6) counterion noted in the solid state (O-bound to Mn(III)) was conserved in the CD(sub 3)OD molecule.

Soluble electron-transfer oxidants are often used as a reagent class in chemistry. New methods are required to developed soluble, nondegradable, metal-based oxidants so that spent reagent can be collected for recharging and reuse. Ligand design was used to produce aliphatic hydrocarbon soluble metal-based oxidants, precipitating quantitatively after electron transfer.

A macrocyclic tetraamido ligand 5,6:(3-pyrido)-12,12-diethyl-2,2,9,9-tetramethyl-3,8,11,13-tetraoxo-1,4,7-10-tetraazacyclotridecane, H4 is designed to incorporate Co(super II) and Co (super III) in the primary coordination site and has a secondary bidentate site, comprising pyridine-N and amido-O donor atoms, that coordinates Lewis acids.

The XAS data for Na[(Mn(super v) triple bond O(HMPAB)], 1, a crystallographically characterized species containing the manganyl unit is analyzed. The results indicates that the preedge transition is the most dependable method for investigating the presence of Mn=O species, and further suggests that it might be correct to reconsider the validity of mechanisms that invoke Mn=O prior to the catalytically active S(sub 4) state.

The vibrational spectrum of the Ci form of the unperturbed (D20)8 cluster was calculated using density functional theory. The calculated frequencies ranged from near 2300 to 2800 cm-1 with the two most intense transitions being predicted to occur at 2300 and 2610 cm-1. The results showed that the observed spectrum differed appreciably from the calculation for the unperturbed cluster which was not surprising because of the structural changes induced by the interactions with the host.

A study was conducted to characterize a technique for O-atom transfer processes. Single turnover conditions were used to determine the effects of the oxidation rate on the transfer process. 1H nuclear magnetic resonance (NMR) and 13C NMR spectroscopy were carried out to observe secondary ion binding. Experimental results indicated that an activator combination supported a mild selective and stable catalyst for O-atom transfers.

The replacement of peripheral ethyl with methyl ligand substituents in the six-membered ring of macrocyclic tetraamides is necessary for obtaining long-lived, iron-based activators that can usefully activate H2O2 for oxidation in water from neutral to basic pH. An H2O2 activator containing a geminal dimethyl group was compared to another containing a geminal diethyl group. The former was synthesized and its efficacy as an H2O2 activator for bleaching pinacyanol chloride was assessed. This activator was deemed effective for a variety of valuable oxidation processes.

The X-ray crystal structure and hydrogen-bonding patterns of the title compound, C18H17N3O3·C5H5N, a non- N-alkyl­ated cyclotripeptide containing one α- and two β-amino acids, are reported. The amides in the 11-membered ring have an unprecedented all- transoid configuration. The torsion angles and Dunitz parameters describing non-planarity of the amides contained in the cyclotripeptide are discussed. [ABSTRACT FROM AUTHOR]

The oxygen-evolving complex of photosystem II is responsible for the four-electron conversion of water to dioxygen via photooxidation of a tetranuclear manganese cluster. Four photon-induced charge separations drive transitions between five oxidation levels named S&sub0;-S4. The most oxidized species, S4, is unstable, releasing O&sub2; and regenerating S&sub0;. Recently, the manganyl moiety, has been suggested to be catalytically important in one or more of the higher S-states.

Estimating statistical significance of the difference between two spectra or series is a fundamental statistical problem. Multivariate significance tests exist but the limitations preclude their use in many common cases; e.g., one-sided testing, unequal variance and when few repetitions are acquired all of which are required in magnetic spectroscopy of nanoparticle Brownian motion (MSB). We introduce a test, termed the T-S test, that is powerful and exact (exact type I error). It is flexible enough to be one- or two-sided and the one-sided version can specify arbitrary regions where each spectrum should be larger. The T-S test takes the-one or two-sided p-value at each frequency and combines them using Stouffer's method. We evaluated it using simulated spectra and measured MSB spectra. For the single-sided version, mean of the spectrum, A-T, was used as a reference; the T-S test is as powerful when the variance at each frequency is uniform and outperforms when the noise power is not uniform. For the two-sided version, the Hotelling T2 two-sided multivariate test was used as a reference; the two-sided T-S test is only slightly less powerful for large numbers of repetitions and outperforms rather dramatically for small numbers of repetitions. The T-S test was used to estimate the sensitivity of our current MSB spectrometer showing 1 nanogram sensitivity. Using eight repetitions the T-S test allowed 15 pM concentrations of mouse IL-6 to be identified while the mean of the spectra only identified 76 pM.