Bis{2,6‐bis[3‐(2,4,6‐trimethylphenyl)pyrazol‐1‐yl‐κN2]pyridine‐κN}zinc(II) diperchlorate bis(nitromethane) solvate

The title compound, [Zn(C₂₉H₂₉N₅)₂](ClO₄)₂·2CH₃NO₂, contains a Zn^II ion showing only small deviations from local D_2d symmetry. The lower rhombicity exhibited by this complex compared with that of its Cu^II congener suggests that the highly rhombic stereochemistry exhibited by the latter is largely imposed by the stereoelectronic preferences of the Cu^II ion.     

Programmed discrimination of qbits with added classical information

We investigate some properties of programmed quantum-state discriminators with simple programs. Bergou et al. [Phys. Rev. A 73, 062334 (2006)] have considered programmable devices which are supplied with two distinct but unknown program qbits and one data qbit which is certain to be identical to one or other of the program qbits. The task is to discriminate between the first and the second possibility. In this paper, we consider this state-discrimination problem when there is some additional classical information available. We find that in the minimum error discrimination mode, the probability of correct discrimination is increased by each type of classical information. The same is broadly true of unambiguous discrimination, with the chance of success improving when the overlap between the program qbits is reduced.     

Estimation of Treatment Time for Microbial Preprocessing of Biomass

Biochemical conversion of lignocellulosic biomass to ethanol involves size reduction, preprocessing, pretreatment, enzyme hydrolysis, and fermentation. In recent years, microbial preprocessing has been gaining attention as a means to produce labile biomass for lessening the requirement of pretreatment severity. However, loss of sugars due to microbial consumption is a major consequence, suggesting its minimization through optimization of nutrients, temperature, and preprocessing time. In this work, we emphasized estimation of fungal preprocessing time, at which higher sugar yields can be achieved after preprocessing and enzyme hydrolysis. The estimation is based on the enzymatic activity profile obtained by treating switchgrass with Phanerochaete chrysosporium for 28 days. Enzyme assays were conducted once in every 7 days for 28 days, for activities of phenol oxidase, peroxidase, β-glucosidase, β-xylosidase, and cellobiohydrolase. We found no activity for phenol oxidase and peroxidase, but the greatest activities for cellulases on the seventh day. We then treated switchgrass for 7 days with P. chrysosporium and observed that the preprocessed switchgrass had higher glucan (39%), xylan (17.5%), and total sugar yields (25.5%) than the unpreprocessed switchgrass (34%, 37.5%, and 20.5%, respectively, p < 0.05). This verifies the utility of using enzyme assays for initial estimation of preprocessing time to enhance sugar yields.     

Self-assembled alkanethiol structures on gold: A further insight into the origins of structural rearrangement phenomena

Self-assembled structures of alkanethiols that have been deposited on gold from ethanolic solutions are susceptible to both chemical and physical changes: ethanol provides a medium for the formation of S-alkyl hydrogen thiocarbonates and related compounds via reaction with dissolved, atmospheric, CO₂. Deposition from ethanolic solutions results in multilayered structures incorporating these compounds, which at room temperature are susceptible to time-dependent structural rearrangement and molecular migration.     

In situ analysis of solvents on breath and blood: a selected ion flow tube mass spectrometric study

We report measurements of residual vapour levels of xylenes and trimethylbenzenes, present following a floor re-surfacing procedure, using the technique of selected ion flow tube mass spectrometry (SIFT-MS). A subject exposed to controlled amounts of xylene and mesitylene was monitored by direct breath exhalation over a 4-hour period after exposure to the volatile organic compounds (VOCs) had stopped. The headspace gases above 5 mL blood samples taken over this period were also monitored. The decays of the solvent levels with time were fitted to a two-compartment model with residence times for xylene and mesitylene of 0.37 h and 0.38 h, respectively (compartment one) and 2.5 h and 2.8 h, respectively (compartment two).     

Selectivity differences between sol-gel coated and immobilized liquid film open-tubular columns for gas chromatography

The solvation parameter model is used to determine the system constants for two sol-gel coated open-tubular columns at five equally spaced temperatures in the range 60-140 degrees C. Differences in the system constants as a function of temperature are used to determine the affect of sol-gel structure on the selectivity of SolGel-l and SolGel-Wax columns compared with conventionally coated and immobilized poly(dimethylsiloxane) and poly(ethylene glycol) stationary phases. The sol-gel columns should be suitable for similar separations to those presently performed on conventional immobilized liquid film columns of the same type but selectivity differences for polar compounds, which depend on temperature, should be anticipated.     

A cyclic hexacopper(II) fluoro complex that encapsulates two fluoride anions

The complex [[Cu3(HpztBu)4(mu-pztBu)2(mu-F)2(mu 3-F)]2]F2 (HpztBu = 3[5]-tert-butylpyrazole) has a cyclic, C2v-symmetric hexacopper core. The two non-coordinated F- anions are encapsulated within cavities formed by three HpztBu ligands.