Multiple H-Rearrangements in 10-Benzylthio-dithranol Radical Cations

10-Alkylthio- and 10-arylthio-derivatives of dithranol (anthralin; 1,8-dihydroxy-9-anthrone) are of interest in search for new anti-psoriatic agents2 , 3 ). By working out ms procedures for unequivocal identification of trace amounts of these compounds4 ) it was established that in case of 10-phenylthio-dithranol putative by-products, especially one giving rise to ions at m/z = 226 (dithranol), are artefacts of thermal reaction in the mass spectrometer1). In the EI-MS of those 10-substituted dithranols containing a S-CH2R chain, however, these ions (m/z = 226) arise from M + * as well. Scope and mechanism of their formation was examined by analyzing compound 1 and its D-labelled derivatives 2 and 3

Analysis of thin-film structures with nuclear backscattering and x-ray diffraction

Backscattering of MeV ^(4)He ions and Seemann-Bohlin x-ray diffraction techniques have been used to study silicide formation on Si and SiO_2 covered with evaporated metal films. Backscattering techniques provide information on the composition of thin-film structures as a function of depth. The glancing-angle x-ray technique provides identification of phases and structural information. Examples are given of V on Si and on SiO_2 to illustrate the major features of these analysis techniques. We also give a general review of recent studies of silicide formation

Biosolids-Derived Biochar for Triclosan Removal from Wastewater

Micropollutants, including antibiotics, hormones, pharmaceuticals, and personal care products, are discharged into the environment with liquid and solid effluent streams from water resource recovery facilities (WRRFs). The objective of this research was to determine whether biosolids-derived biochar (BS-biochar) could be used as a sorbent in continuous flow-through columns to remove micropollutants as a polishing step for wastewater treatment. Triclosan (TCS) was selected as a representative micropollutant due to frequent detection in liquid effluents, residual biosolids, and surface waters. Bench-scale column experiments were conducted to determine the effect of flow rate and competition due to the presence of other organic micropollutants and inorganic nutrients on TCS adsorption to BS-biochar. TCS removal efficiency was compared in Milli-Q water and secondary wastewater effluent by using two commercial adsorbents: a granular activated carbon and a wood-based biochar. Increased removal of TCS was observed at lower flow rates (2.6 gpm/ft2) compared with higher flow rates (10.3 gpm/ft2). Presence of inorganic nutrients (NH4+ and PO43−) and organic micropollutants 17β-estradiol and sulfamethoxazole decreased adsorption of TCS to BS-biochar. TCS was sorbed to BS-biochar in wastewater, but percent removal decreased in wastewater relative to Milli-Q water. This study demonstrated that BS-biochar can remove TCS from wastewater in continuous flow-through columns, although to a lesser extent than activated carbon. An additional benefit of using BS-biochar is that WRRFs could re-activate biochar on-site by using a pyrolysis reactor

Removal of Trace Metal Contaminants from Potable Water by Electrocoagulation

This study investigated the effects of four operational and environmental variables on the removal of trace metal contaminants from drinking water by electrocoagulation (EC). Removal efficiencies for five metals (arsenic, cadmium, chromium, lead and nickel) were compared under varying combinations of electrode material, post-treatment, water composition and pH. Iron electrodes out-performed aluminum electrodes in removing chromium and arsenic. At pH 6.5, aluminum electrodes were slightly more effective at removing nickel and cadmium, while at pH 8.5, iron electrodes were more effective for these metals. Regardless of electrode, cadmium and nickel removal efficiencies were higher at pH 8.5 than at pH 6.5. Post-EC treatment using membrane filtration (0.45 μm) enhanced contaminant removal for all metals but nickel. With the exception of lead, all metals exhibited poorer removal efficiencies as the ionic strength of the background electrolyte increased, particularly in the very high-solids synthetic groundwaters. Residual aluminum concentrations were lowest at pH 6.5, while iron residuals were lowest in low ionic strength waters. Both aluminum and iron residuals required post-treatment filtration to meet drinking water standards. EC with post-treatment filtration appears to effectively remove trace metal contaminants to potable water standards, but both reactor and source water parameters critically impact removal efficiency

Triclosan Adsorption Using Wastewater Biosolids-derived Biochar

Organic micropollutants are ubiquitous in the environment and stem from municipal wastewater treatment plant discharges. Adsorption can be used as a tertiary treatment to complement the conventional activated sludge process to remove micropollutants prior to discharge. This research evaluated the performance of wastewater biosolids-derived biochar as an adsorbent to remove triclosan from water. Pre-conditioning of the biochar using hydrochloric acid (HCl) was an essential step for triclosan adsorption. Using acid-conditioned biochar, maximum adsorption of 872 μg triclosan per g biochar was achieved with biochar produced at 800 °C. Biochar produced at higher pyrolysis temperatures tended to have higher triclosan sorption capacity using initial triclosan concentrations of 200 μg L−1 levels. However, pyrolysis temperature had less impact on triclosan sorption at lower, environmentally relevant concentrations. Low solution pH (3) enhanced adsorption and high pH (11) inhibited adsorption. Effective triclosan sorption was observed between pH 5 and 9, with little variation, which is positive for practical applications operated at near-neutral solution pH. In wastewater, acid-treated biochar also effectively sorbed triclosan, albeit at a decreased adsorption capacity and removal rate due to competition from other organic constituents. This study indicated that adsorption may occur mainly due to high surface area, hydrophobicity, and potential interaction between biochar and triclosan functional groups including hydrogen bonding and π-stacking. This work demonstrated that acid-conditioned biosolids-derived biochar could be a suitable sorbent to remove triclosan from wastewater as a final polishing treatment step

The application of LANDSAT remote sensing technology to natural resources management. Section 1: Introduction to VICAR - Image classification module. Section 2: Forest resource assessment of Humboldt County.

A teaching module on image classification procedures using the VICAR computer software package was developed to optimize the training benefits for users of the VICAR programs. The field test of the module is discussed. An intensive forest land inventory strategy was developed for Humboldt County. The results indicate that LANDSAT data can be computer classified to yield site specific forest resource information with high accuracy (82%). The "Douglas-fir 80%" category was found to cover approximately 21% of the county and "Mixed Conifer 80%" covering about 13%. The "Redwood 80%" resource category, which represented dense old growth trees as well as large second growth, comprised 4.0% of the total vegetation mosaic. Furthermore, the "Brush" and "Brush-Regeneration" categories were found to be a significant part of the vegetative community, with area estimates of 9.4 and 10.0%

Aspects of a sociology of the pandemic: Inequalities and the life course

Over the course of the COVID-19 pandemic, the contributions of the social sciences to discussions about pandemic management have become more visible and more significant. In this essay, I review major aspects of a sociology of the pandemic. After providing an overview of the potential contributions of the different fields of sociology (the “toolbox” of sociology), I discuss two main domains: first, social inequalities and how they relate to the process of the spread of COVID-19 from exposure and infection, and to the consequences of the pandemic in the wider population; and, second, the potential long-term effects of the pandemic on the life course

A Comparative Life Cycle Assessment between a Metered Dose Inhaler and Electric Nebulizer

Life cycle assessment (LCA) evaluates the environmental impact of a product based on the materials and processes used to manufacture the item as well as the item’s use and disposal. The objective of this LCA was to evaluate and compare the environmental impact of a metered dose inhaler, specifically the Proventil® HFA inhaler (Merk & Co., Inc., Kenilworth, NJ, USA), and an electric nebulizer, specifically the DeVilbiss Pulmo-Aide® nebulizer (DeVilbiss, Port Washington, NY, USA). GaBi LCA software was used to model the global warming potential (GWP) of each product by using substantiated data and well-justified assumptions for the components, manufacturing, assembly, and use of both devices. The functional unit used to model each device was one dose of the active drug, albuterol sulfate. The inhaler’s GWP, 0.0972 kg CO2-eq, was greater than the nebulizer’s even when uncertain parameters were varied ±100x. During the use phase ofa the inhaler, which accounted for approximately 96% of the inhaler’s total GWP, HFA 134a is used as a propellant to deliver the drug. The total GWP for the electric nebulizer was 0.0294 kg CO2-eq assuming that the mouthpiece was cleaned in a dishwasher, while it was 0.0477 kg CO2-eq when the nebulizer mouthpiece was hand washed between uses. The GWP breakeven scenario between dishwashing and hand washing occurred when the mouthpiece accounted for 10% of the dishwasher load