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1. Organic Semiconductors at the University of Washington: Advancements in Materials Design and Synthesis and toward Industrial Scale Production

   https://doi.org/10.1002/adma.201904239  

   Huang, Yunping ; Elder, Delwin L. ; Kwiram, Alvin L. ; Jenekhe, Samson A. ; Jen, Alex K. Y. ; Dalton, Larry R. ; Luscombe, Christine K. ( October 2019 , Advanced Materials)

   Research at the University of Washington regarding organic semiconductors is reviewed, covering four major topics: electro‐optics, organic light emitting diodes, organic field‐effect transistors, and organic solar cells. Underlying principles of materials design are demonstrated along with efforts toward unlocking the full potential of organic semiconductors. Finally, opinions on future research directions are presented, with a focus on commercial competency, environmental sustainability, and scalability of organic‐semiconductor‐based devices.

    

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2. How Values Shape Program Perceptions: The “Organic Ethos” and Producers’ Assessments of U.S. Organic Policy Impacts

   https://doi.org/10.1111/ropr.12330  

   Carter, David P. ; Mosier, Samatha L. ; Adams, Ian T. ( February 2019 , Review of Policy Research)

   Among the more recognizable programs related to natural and sustainable food is the United States Department of Agriculture’s National Organic Program. Although the robustness of the organic food market is difficult to contest, many debate the extent to which U.S. organic policy outcomes adequately serve consumers and the organic agriculture producers they rely on. This paper engages the debate from the perspective of certified organic producers. Drawing on the results of a nationwide survey of USDA‐certified producers, we first provide a snapshot of how producers assess the environmental, consumer, and market impacts of U.S. organic food policy. We then examine the extent to which organic producers’ policy impact perceptions are associated with their alignment with an “organic ethos”—understood as producers’ commitment to core organic principles and the organic movement. The paper highlights producers’ values as perceptual filters and cognitive mechanisms that help shape producers’ policy impacts perceptions, illustrating a contributing factor to the enduring nature of organic policy debates.

    

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3. Organic sulfur: A spatially variable and understudied component of marine organic matter

   https://doi.org/10.1002/lol2.10149  

   Longnecker, Krista ; Oswald, Lisa ; Kido Soule, Melissa C. ; Cutter, Gregory A. ; Kujawinski, Elizabeth B. ( February 2020 , Limnology and Oceanography Letters)

   Sulfur (S) is a major heteroatom in organic matter. This project evaluated spatial variability in the concentration and molecular‐level composition of organic sulfur along gradients of depth and latitude. We measured the concentration of total organic sulfur (TOS) directly from whole seawater. Our data reveal high variability in organic sulfur, relative to established variability in total organic carbon or nitrogen. The deep ocean contained significant amounts of organic sulfur, and the concentration of TOS in North Atlantic Deep Water (NADW) decreased with increasing age while total organic carbon remained stable. Analysis of dissolved organic matter extracts by ultrahigh resolution mass spectrometry revealed that 6% of elemental formulas contained sulfur. The sulfur‐containing compounds were structurally diverse, and showed higher numbers of sulfur‐containing elemental formulas as NADW moved southward. These measurements of organic sulfur in seawater provide the foundation needed to define the factors controlling organic sulfur in the global ocean.

    

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4. Fluorescence characterization of organic matter and fouling: Case study in a full‐scale reverse osmosis membrane treatment plant

   https://doi.org/10.1002/wer.1236  

   Bergman, Lauren E. ; Jones, Kimberly L. ; VanBriesen, Jeanne M. ( September 2019 , Water Environment Research)

   Membranes used for water treatment are subject to organic fouling, caused by organic matter in source water. Characterizing organic matter has the potential to improve fouling prediction since the development of an organic fouling layer on the membrane is dependent on the specific characteristics of the organic matter. A field study was performed at a full‐scale reverse osmosis water treatment plant that treats secondary wastewater effluent for industrial reuse at a power plant. Samples were collected at various points within the treatment process and were analyzed for turbidity, total organic carbon (TOC), conductivity, and fluorescence Excitation Emission Matrices (EEM). Parallel factor analysis (PARAFAC) was used to generate representative fluorescence measurements of the organic matter. Results indicate that TOC and fluorescence measurements were effective in differentiating between two observed fouling periods at multiple locations within the treatment plant. However, none of the water quality measurements were effective in tracking treatability of organic matter throughout pretreatment. The results of this case study provide important information about the relationship between fluorescence NOM signals and membrane fouling that can be used in future online detection systems.

   TOC and fluorescence measurements were effective in differentiating between the high fouling and low fouling periods.

   Water quality measurements were not effective in tracking changes in organic matter throughout pretreatment.

   Implementation of online fluorescence monitoring of fouling potential could be used for real‐time process control.

    

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5. Salmon‐derived nutrient and organic matter fluxes from a coastal catchment in southeast Alaska

   https://doi.org/10.1111/fwb.13292  

   Hood, Eran ; Fellman, Jason B. ; Edwards, Rick T. ; D'Amore, David V. ; Scott, Durelle ( March 2019 , Freshwater Biology)

   Salmon are important vectors for biogeochemical transport across ecosystem boundaries. Here we quantified salmon contributions to annual catchment fluxes of nutrients (N and P) and organic matter (C, N, and P) from a forested catchment in coastal southeast Alaska.

   Concentrations of ammonium and soluble reactive phosphorus increased by several orders of magnitude during spawning and were significantly correlated with spawning salmon densities. Nitrate concentrations increased modestly during spawning and were not significantly correlated with salmon densities. Salmon had a modest legacy effect on inorganic N and P as evidenced by elevated streamwater concentrations past the end of the spawning period.

   Dissolved organic carbon concentrations did not respond to the presence of salmon; however, concentrations of dissolved organic nitrogen and phosphorus showed a significant positive relationship to salmon densities. Changes in spectroscopic properties of the bulk streamwater dissolved organic matter pool indicated that streamwater dissolved organic matter became less aromatic and biolabile during spawning.

   On an annual basis, salmon were the dominant source of streamwater fluxes of inorganic nutrients, accounting for 92%, 65%, and 74% of annual streamwater fluxes of ammonium, nitrate, and soluble reactive phosphorus, respectively. In contrast, fluxes of organic matter were dominated by catchment sources with salmon accounting for <1% of the annual catchment flux of dissolved organic carbon and 12% and 15% of the annual fluxes of dissolved organic nitrogen and phosphorous respectively.

   These findings indicate that, in small coastal catchments, salmon can be a quantitatively important source of dissolved streamwater nutrients with implications for productivity in downstream estuarine ecosystems.

    

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