Notes

The ILs are arranged in the decreasing order of their ionic conductivities as [P4444][HFuA] (069 mS cm-1) > [P4444][FuA] (032 mS cm-1) > [P4444][TpA] (028 mS cm-1) at 20 °C
The oxidative limit of the ILs followed the sequence of [FuA]-> [TpA]-> [HFuA]-, as measured by linear sweep voltammetry. This order can be attributed to the electrons' delocalization in [FuA]- and in [TpA]- aromatic anions, which has enhanced the oxidative limit potentials and the overall electrochemical stabilities.Chemical Alterations of Dissolved Organic Matter by Permanganate Oxidation.University, Columbus, Ohio 43210, United States.State University, Columbus, Ohio 43210, United States.Dissolved organic matter (DOM) is ubiquitous in raw drinking water and can efficiently scavenge oxidants, such as permanganate.

Here, changes to DOM induced by permanganate oxidation under typical drinking water treatment conditions (6 μM, 1 h) to bulk DOM properties, DOM functional groups, and DOM chemical formulae were examined for two DOM isolate types (terrestrial and microbial). Permanganate oxidation did not mineralize DOM, rather changes were compositional in nature. Optical properties suggest that permanganate oxidation decreased DOM aromaticity (decreased SUVA-254), decreased DOM electron-donating capacity, and decreased DOM average molecular weight (increased E2/E3 ratios). Fourier-transform-infrared spectroscopy second derivative analyses revealed that permanganate does not oxidize DOM alkene groups, suggesting permanganate access to functional groups may be important. Four ionization techniques were used with ultrahigh-resolution mass spectrometry: negative and positive ion mode electrospray ionization and negative and positive ion mode laser/desorption ionization. The results from all four techniques were combined to understand changes in DOM chemical formulae. It was concluded that nitrogen-containing aromatic compounds and alkylbenzenes were oxidized by permanganate to form nitrogen-containing aliphatic compounds and benzoic acid-containing compounds.

This work highlights how multiple ionization techniques coupled with UHR-MS can enable a more detailed characterization of DOM.Interplay of Biradicaloid Character and Singlet/Triplet Energy Splitting for cis-/trans-Diindenoacenes and Related Benzothiophene-Capped Oligomers as Revealed by Extended Multireference Calculations.University of Oregon, Eugene, Oregon 97403, United States.The biradicaloid character of different types of polycyclic aromatic hydrocarbons is an important quality that guides the development of new materials with interesting magneto-optical properties. 6-butyl-n-hydroxynaphthimide trifluoromethanesulfonic acid in Electrophilic Aromatic Substitution -based systems represent such a class of promising compounds. In this work, the three types trans-diindenoacenes, cis-diindenoacenes, and trans-dicyclopentaacenobis(benzothiophenes) have been studied by means of advanced ab initio methods. The descriptors singlet/triplet splitting energy (ΔES-T), effective number of unpaired electrons (NU), unpaired electron density, and the harmonic oscillator measure of aromaticity have been used to characterize the biradicaloid properties of these species.

For all trans structures, low-spin singlet ground states were found, in agreement with previous investigations. Increasing the length of the inner acene chain decreased the ΔES-T and strongly increased the NU values of the singlet state. The cis-diindenoacenes displayed a greatly increased biradicaloid character, indicating enhanced chemical instability. The thiophene rings in the trans-dicyclopentaacenobis(benzothiophenes) structures were found to simultaneously restrict the unpaired electron density from extending into the terminal six-membered rings and confine the unpaired electron density found in Demonstration of Chemical Distinction among Soil Humic Fractions Using Humic substances (HS) are vital to soil fertility and carbon sequestration. Using multiple cross-polarization/magic-angle spinning (multiCP/MAS) NMR combined with dipolar dephasing, we quantitatively characterized humic fractions, i.e., fulvic acid (FA), humic acid (HA), and humin (HM), isolated long-term (>20 years) fertilizer treatments.

Results indicate that each humic fraction showed chemical distinction between the upland and paddy soils, especially with much greater aromaticity of upland HMs than of paddy HMs. Fertilizer treatment exerted greater influence on chemical natures of upland HS than of paddy HS, although the effect was less than that of soil type. Organic manure application especially decreased the percentages of aromatic C in the upland HAs and HMs compared with the control. We concluded that humic fractions responded in chemical nature to environmental conditions, i.e., soil type/cropping system/soil aeration and fertilizer treatments.[Day-night Characteristics of Humic-like Substances in PM(2) During Winter in To investigate the characteristics of diurnal variation of humic-like substances (HULIS) in atmospheric aerosols during winter in Changzhou, a total of 64 fine particle (PM2) samples were collected from January 1 to February 28, 2017.

In Seebio Photoresponsive Acid Precursor , the concentration as well as light absorption parameters of humic-like substances of carbon (HULIS-C) were examined. The results showed that the average day PM2 and HULIS-C concentrations were 1220 μg·m-3 and 48 μg·m-3, respectively, slightly higher than those (1112 μg·m-3 and 34 μg·m-3) at night.
Read More: http://en.wikipedia.org/wiki/Photoresist